InstructionSimplify.cpp revision 0b8c9a80f20772c3793201ab5b251d3520b9cea3
19f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner//===- InstructionSimplify.cpp - Fold instruction operands ----------------===// 29f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner// 39f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner// The LLVM Compiler Infrastructure 49f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner// 59f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner// This file is distributed under the University of Illinois Open Source 69f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner// License. See LICENSE.TXT for details. 79f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner// 89f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner//===----------------------------------------------------------------------===// 99f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner// 109f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner// This file implements routines for folding instructions into simpler forms 114cd2ad15b43f21d641330b4b09961af08646445eDuncan Sands// that do not require creating new instructions. This does constant folding 124cd2ad15b43f21d641330b4b09961af08646445eDuncan Sands// ("add i32 1, 1" -> "2") but can also handle non-constant operands, either 134cd2ad15b43f21d641330b4b09961af08646445eDuncan Sands// returning a constant ("and i32 %x, 0" -> "0") or an already existing value 14ee9a2e322af96accc9e55ed6373c0057453714b1Duncan Sands// ("and i32 %x, %x" -> "%x"). All operands are assumed to have already been 15ee9a2e322af96accc9e55ed6373c0057453714b1Duncan Sands// simplified: This is usually true and assuming it simplifies the logic (if 16ee9a2e322af96accc9e55ed6373c0057453714b1Duncan Sands// they have not been simplified then results are correct but maybe suboptimal). 179f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner// 189f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner//===----------------------------------------------------------------------===// 199f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner 20a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands#define DEBUG_TYPE "instsimplify" 219f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner#include "llvm/Analysis/InstructionSimplify.h" 22d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/ADT/SetVector.h" 23d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/ADT/Statistic.h" 24f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky#include "llvm/Analysis/AliasAnalysis.h" 259f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner#include "llvm/Analysis/ConstantFolding.h" 261845009290e4d804ad377927bd8a08cca3036adcDuncan Sands#include "llvm/Analysis/Dominators.h" 27d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands#include "llvm/Analysis/ValueTracking.h" 280b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/DataLayout.h" 290b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/GlobalAlias.h" 300b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/Operator.h" 313a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky#include "llvm/Support/ConstantRange.h" 32fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth#include "llvm/Support/GetElementPtrTypeIterator.h" 33d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner#include "llvm/Support/PatternMatch.h" 341845009290e4d804ad377927bd8a08cca3036adcDuncan Sands#include "llvm/Support/ValueHandle.h" 359f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattnerusing namespace llvm; 36d06094f0682f2ede03caff4892b1a57469896d48Chris Lattnerusing namespace llvm::PatternMatch; 379f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner 3881a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattnerenum { RecursionLimit = 3 }; 39a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 40a3c44a5280042dbc0cde995675c225ede4528c6eDuncan SandsSTATISTIC(NumExpand, "Number of expansions"); 41a3c44a5280042dbc0cde995675c225ede4528c6eDuncan SandsSTATISTIC(NumFactor , "Number of factorizations"); 42a3c44a5280042dbc0cde995675c225ede4528c6eDuncan SandsSTATISTIC(NumReassoc, "Number of reassociations"); 43a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands 440aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstruct Query { 453574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD; 460aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const TargetLibraryInfo *TLI; 470aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const DominatorTree *DT; 480aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands 493574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow Query(const DataLayout *td, const TargetLibraryInfo *tli, 509133783d5483e38b16af6c10df7a8bbe655d3446Bill Wendling const DominatorTree *dt) : TD(td), TLI(tli), DT(dt) {} 510aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands}; 520aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands 530aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyAndInst(Value *, Value *, const Query &, unsigned); 540aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyBinOp(unsigned, Value *, Value *, const Query &, 55618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier unsigned); 560aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyCmpInst(unsigned, Value *, Value *, const Query &, 57618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier unsigned); 580aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyOrInst(Value *, Value *, const Query &, unsigned); 590aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyXorInst(Value *, Value *, const Query &, unsigned); 60bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sandsstatic Value *SimplifyTruncInst(Value *, Type *, const Query &, unsigned); 611845009290e4d804ad377927bd8a08cca3036adcDuncan Sands 62f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands/// getFalse - For a boolean type, or a vector of boolean type, return false, or 63f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands/// a vector with every element false, as appropriate for the type. 64f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sandsstatic Constant *getFalse(Type *Ty) { 6566d004ef708642bbdc38fd761507f2e9ee3970cdNick Lewycky assert(Ty->getScalarType()->isIntegerTy(1) && 66f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands "Expected i1 type or a vector of i1!"); 67f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return Constant::getNullValue(Ty); 68f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands} 69f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands 70f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands/// getTrue - For a boolean type, or a vector of boolean type, return true, or 71f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands/// a vector with every element true, as appropriate for the type. 72f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sandsstatic Constant *getTrue(Type *Ty) { 7366d004ef708642bbdc38fd761507f2e9ee3970cdNick Lewycky assert(Ty->getScalarType()->isIntegerTy(1) && 74f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands "Expected i1 type or a vector of i1!"); 75f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return Constant::getAllOnesValue(Ty); 76f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands} 77f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands 786dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands/// isSameCompare - Is V equivalent to the comparison "LHS Pred RHS"? 796dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sandsstatic bool isSameCompare(Value *V, CmpInst::Predicate Pred, Value *LHS, 806dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands Value *RHS) { 816dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands CmpInst *Cmp = dyn_cast<CmpInst>(V); 826dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands if (!Cmp) 836dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands return false; 846dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands CmpInst::Predicate CPred = Cmp->getPredicate(); 856dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands Value *CLHS = Cmp->getOperand(0), *CRHS = Cmp->getOperand(1); 866dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands if (CPred == Pred && CLHS == LHS && CRHS == RHS) 876dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands return true; 886dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands return CPred == CmpInst::getSwappedPredicate(Pred) && CLHS == RHS && 896dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands CRHS == LHS; 906dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands} 916dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands 921845009290e4d804ad377927bd8a08cca3036adcDuncan Sands/// ValueDominatesPHI - Does the given value dominate the specified phi node? 931845009290e4d804ad377927bd8a08cca3036adcDuncan Sandsstatic bool ValueDominatesPHI(Value *V, PHINode *P, const DominatorTree *DT) { 941845009290e4d804ad377927bd8a08cca3036adcDuncan Sands Instruction *I = dyn_cast<Instruction>(V); 951845009290e4d804ad377927bd8a08cca3036adcDuncan Sands if (!I) 961845009290e4d804ad377927bd8a08cca3036adcDuncan Sands // Arguments and constants dominate all instructions. 971845009290e4d804ad377927bd8a08cca3036adcDuncan Sands return true; 981845009290e4d804ad377927bd8a08cca3036adcDuncan Sands 99ff739c1575df58f3926c2f3b6e00a6c45f773523Chandler Carruth // If we are processing instructions (and/or basic blocks) that have not been 100ff739c1575df58f3926c2f3b6e00a6c45f773523Chandler Carruth // fully added to a function, the parent nodes may still be null. Simply 101ff739c1575df58f3926c2f3b6e00a6c45f773523Chandler Carruth // return the conservative answer in these cases. 102ff739c1575df58f3926c2f3b6e00a6c45f773523Chandler Carruth if (!I->getParent() || !P->getParent() || !I->getParent()->getParent()) 103ff739c1575df58f3926c2f3b6e00a6c45f773523Chandler Carruth return false; 104ff739c1575df58f3926c2f3b6e00a6c45f773523Chandler Carruth 1051845009290e4d804ad377927bd8a08cca3036adcDuncan Sands // If we have a DominatorTree then do a precise test. 1065b8f0ddc7e5bc3c7ffe1b2226a8316796f18b90eEli Friedman if (DT) { 1075b8f0ddc7e5bc3c7ffe1b2226a8316796f18b90eEli Friedman if (!DT->isReachableFromEntry(P->getParent())) 1085b8f0ddc7e5bc3c7ffe1b2226a8316796f18b90eEli Friedman return true; 1095b8f0ddc7e5bc3c7ffe1b2226a8316796f18b90eEli Friedman if (!DT->isReachableFromEntry(I->getParent())) 1105b8f0ddc7e5bc3c7ffe1b2226a8316796f18b90eEli Friedman return false; 1115b8f0ddc7e5bc3c7ffe1b2226a8316796f18b90eEli Friedman return DT->dominates(I, P); 1125b8f0ddc7e5bc3c7ffe1b2226a8316796f18b90eEli Friedman } 1131845009290e4d804ad377927bd8a08cca3036adcDuncan Sands 1141845009290e4d804ad377927bd8a08cca3036adcDuncan Sands // Otherwise, if the instruction is in the entry block, and is not an invoke, 1151845009290e4d804ad377927bd8a08cca3036adcDuncan Sands // then it obviously dominates all phi nodes. 1161845009290e4d804ad377927bd8a08cca3036adcDuncan Sands if (I->getParent() == &I->getParent()->getParent()->getEntryBlock() && 1171845009290e4d804ad377927bd8a08cca3036adcDuncan Sands !isa<InvokeInst>(I)) 1181845009290e4d804ad377927bd8a08cca3036adcDuncan Sands return true; 1191845009290e4d804ad377927bd8a08cca3036adcDuncan Sands 1201845009290e4d804ad377927bd8a08cca3036adcDuncan Sands return false; 1211845009290e4d804ad377927bd8a08cca3036adcDuncan Sands} 122a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 1233421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands/// ExpandBinOp - Simplify "A op (B op' C)" by distributing op over op', turning 1243421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands/// it into "(A op B) op' (A op C)". Here "op" is given by Opcode and "op'" is 1253421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands/// given by OpcodeToExpand, while "A" corresponds to LHS and "B op' C" to RHS. 1263421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands/// Also performs the transform "(A op' B) op C" -> "(A op C) op' (B op C)". 1273421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands/// Returns the simplified value, or null if no simplification was performed. 1283421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sandsstatic Value *ExpandBinOp(unsigned Opcode, Value *LHS, Value *RHS, 1290aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands unsigned OpcToExpand, const Query &Q, 130618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier unsigned MaxRecurse) { 131e21083aa3a79506f896d95d7147c3c4627a77ef0Benjamin Kramer Instruction::BinaryOps OpcodeToExpand = (Instruction::BinaryOps)OpcToExpand; 1323421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Recursion is always used, so bail out at once if we already hit the limit. 1333421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (!MaxRecurse--) 1343421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return 0; 1353421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 1363421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Check whether the expression has the form "(A op' B) op C". 1373421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (BinaryOperator *Op0 = dyn_cast<BinaryOperator>(LHS)) 1383421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (Op0->getOpcode() == OpcodeToExpand) { 1393421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // It does! Try turning it into "(A op C) op' (B op C)". 1403421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands Value *A = Op0->getOperand(0), *B = Op0->getOperand(1), *C = RHS; 1413421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Do "A op C" and "B op C" both simplify? 1420aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *L = SimplifyBinOp(Opcode, A, C, Q, MaxRecurse)) 1430aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *R = SimplifyBinOp(Opcode, B, C, Q, MaxRecurse)) { 1443421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // They do! Return "L op' R" if it simplifies or is already available. 1453421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // If "L op' R" equals "A op' B" then "L op' R" is just the LHS. 146124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if ((L == A && R == B) || (Instruction::isCommutative(OpcodeToExpand) 147124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands && L == B && R == A)) { 148a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumExpand; 1493421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return LHS; 150a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 1513421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Otherwise return "L op' R" if it simplifies. 1520aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(OpcodeToExpand, L, R, Q, MaxRecurse)) { 153a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumExpand; 1543421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return V; 155a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 1563421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands } 1573421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands } 1583421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 1593421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Check whether the expression has the form "A op (B op' C)". 1603421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (BinaryOperator *Op1 = dyn_cast<BinaryOperator>(RHS)) 1613421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (Op1->getOpcode() == OpcodeToExpand) { 1623421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // It does! Try turning it into "(A op B) op' (A op C)". 1633421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands Value *A = LHS, *B = Op1->getOperand(0), *C = Op1->getOperand(1); 1643421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Do "A op B" and "A op C" both simplify? 1650aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *L = SimplifyBinOp(Opcode, A, B, Q, MaxRecurse)) 1660aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *R = SimplifyBinOp(Opcode, A, C, Q, MaxRecurse)) { 1673421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // They do! Return "L op' R" if it simplifies or is already available. 1683421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // If "L op' R" equals "B op' C" then "L op' R" is just the RHS. 169124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if ((L == B && R == C) || (Instruction::isCommutative(OpcodeToExpand) 170124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands && L == C && R == B)) { 171a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumExpand; 1723421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return RHS; 173a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 1743421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Otherwise return "L op' R" if it simplifies. 1750aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(OpcodeToExpand, L, R, Q, MaxRecurse)) { 176a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumExpand; 1773421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return V; 178a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 1793421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands } 1803421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands } 1813421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 1823421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return 0; 1833421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands} 1843421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 1853421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands/// FactorizeBinOp - Simplify "LHS Opcode RHS" by factorizing out a common term 1863421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands/// using the operation OpCodeToExtract. For example, when Opcode is Add and 1873421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands/// OpCodeToExtract is Mul then this tries to turn "(A*B)+(A*C)" into "A*(B+C)". 1883421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands/// Returns the simplified value, or null if no simplification was performed. 1893421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sandsstatic Value *FactorizeBinOp(unsigned Opcode, Value *LHS, Value *RHS, 1900aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands unsigned OpcToExtract, const Query &Q, 191618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier unsigned MaxRecurse) { 192e21083aa3a79506f896d95d7147c3c4627a77ef0Benjamin Kramer Instruction::BinaryOps OpcodeToExtract = (Instruction::BinaryOps)OpcToExtract; 1933421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Recursion is always used, so bail out at once if we already hit the limit. 1943421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (!MaxRecurse--) 1953421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return 0; 1963421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 1973421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands BinaryOperator *Op0 = dyn_cast<BinaryOperator>(LHS); 1983421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands BinaryOperator *Op1 = dyn_cast<BinaryOperator>(RHS); 1993421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 2003421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (!Op0 || Op0->getOpcode() != OpcodeToExtract || 2013421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands !Op1 || Op1->getOpcode() != OpcodeToExtract) 2023421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return 0; 2033421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 2043421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // The expression has the form "(A op' B) op (C op' D)". 20582fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands Value *A = Op0->getOperand(0), *B = Op0->getOperand(1); 20682fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands Value *C = Op1->getOperand(0), *D = Op1->getOperand(1); 2073421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 2083421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Use left distributivity, i.e. "X op' (Y op Z) = (X op' Y) op (X op' Z)". 2093421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Does the instruction have the form "(A op' B) op (A op' D)" or, in the 2103421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // commutative case, "(A op' B) op (C op' A)"? 211124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (A == C || (Instruction::isCommutative(OpcodeToExtract) && A == D)) { 212124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands Value *DD = A == C ? D : C; 2133421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Form "A op' (B op DD)" if it simplifies completely. 2143421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Does "B op DD" simplify? 2150aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(Opcode, B, DD, Q, MaxRecurse)) { 2163421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // It does! Return "A op' V" if it simplifies or is already available. 2171cd05bb605e3c3eee9197d3f10b628c60d0cc07aDuncan Sands // If V equals B then "A op' V" is just the LHS. If V equals DD then 2181cd05bb605e3c3eee9197d3f10b628c60d0cc07aDuncan Sands // "A op' V" is just the RHS. 219124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (V == B || V == DD) { 220a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumFactor; 221124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands return V == B ? LHS : RHS; 222a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 2233421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Otherwise return "A op' V" if it simplifies. 2240aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *W = SimplifyBinOp(OpcodeToExtract, A, V, Q, MaxRecurse)) { 225a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumFactor; 2263421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return W; 227a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 2283421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands } 2293421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands } 2303421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 2313421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Use right distributivity, i.e. "(X op Y) op' Z = (X op' Z) op (Y op' Z)". 2323421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Does the instruction have the form "(A op' B) op (C op' B)" or, in the 2333421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // commutative case, "(A op' B) op (B op' D)"? 234124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (B == D || (Instruction::isCommutative(OpcodeToExtract) && B == C)) { 235124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands Value *CC = B == D ? C : D; 2363421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Form "(A op CC) op' B" if it simplifies completely.. 2373421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Does "A op CC" simplify? 2380aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(Opcode, A, CC, Q, MaxRecurse)) { 2393421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // It does! Return "V op' B" if it simplifies or is already available. 2401cd05bb605e3c3eee9197d3f10b628c60d0cc07aDuncan Sands // If V equals A then "V op' B" is just the LHS. If V equals CC then 2411cd05bb605e3c3eee9197d3f10b628c60d0cc07aDuncan Sands // "V op' B" is just the RHS. 242124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (V == A || V == CC) { 243a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumFactor; 244124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands return V == A ? LHS : RHS; 245a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 2463421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Otherwise return "V op' B" if it simplifies. 2470aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *W = SimplifyBinOp(OpcodeToExtract, V, B, Q, MaxRecurse)) { 248a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumFactor; 2493421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return W; 250a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 2513421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands } 2523421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands } 2533421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 2543421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return 0; 2553421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands} 2563421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 2573421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands/// SimplifyAssociativeBinOp - Generic simplifications for associative binary 2583421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands/// operations. Returns the simpler value, or null if none was found. 259e21083aa3a79506f896d95d7147c3c4627a77ef0Benjamin Kramerstatic Value *SimplifyAssociativeBinOp(unsigned Opc, Value *LHS, Value *RHS, 2600aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 261e21083aa3a79506f896d95d7147c3c4627a77ef0Benjamin Kramer Instruction::BinaryOps Opcode = (Instruction::BinaryOps)Opc; 262566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands assert(Instruction::isAssociative(Opcode) && "Not an associative operation!"); 263566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 264566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Recursion is always used, so bail out at once if we already hit the limit. 265566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands if (!MaxRecurse--) 266566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return 0; 267566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 268566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands BinaryOperator *Op0 = dyn_cast<BinaryOperator>(LHS); 269566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands BinaryOperator *Op1 = dyn_cast<BinaryOperator>(RHS); 270566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 271566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Transform: "(A op B) op C" ==> "A op (B op C)" if it simplifies completely. 272566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands if (Op0 && Op0->getOpcode() == Opcode) { 273566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *A = Op0->getOperand(0); 274566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *B = Op0->getOperand(1); 275566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *C = RHS; 276566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 277566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Does "B op C" simplify? 2780aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(Opcode, B, C, Q, MaxRecurse)) { 279566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // It does! Return "A op V" if it simplifies or is already available. 280566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // If V equals B then "A op V" is just the LHS. 281124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (V == B) return LHS; 282566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Otherwise return "A op V" if it simplifies. 2830aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *W = SimplifyBinOp(Opcode, A, V, Q, MaxRecurse)) { 284a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumReassoc; 285566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return W; 286a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 287566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands } 288566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands } 289566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 290566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Transform: "A op (B op C)" ==> "(A op B) op C" if it simplifies completely. 291566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands if (Op1 && Op1->getOpcode() == Opcode) { 292566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *A = LHS; 293566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *B = Op1->getOperand(0); 294566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *C = Op1->getOperand(1); 295566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 296566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Does "A op B" simplify? 2970aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(Opcode, A, B, Q, MaxRecurse)) { 298566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // It does! Return "V op C" if it simplifies or is already available. 299566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // If V equals B then "V op C" is just the RHS. 300124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (V == B) return RHS; 301566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Otherwise return "V op C" if it simplifies. 3020aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *W = SimplifyBinOp(Opcode, V, C, Q, MaxRecurse)) { 303a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumReassoc; 304566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return W; 305a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 306566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands } 307566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands } 308566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 309566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // The remaining transforms require commutativity as well as associativity. 310566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands if (!Instruction::isCommutative(Opcode)) 311566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return 0; 312566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 313566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Transform: "(A op B) op C" ==> "(C op A) op B" if it simplifies completely. 314566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands if (Op0 && Op0->getOpcode() == Opcode) { 315566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *A = Op0->getOperand(0); 316566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *B = Op0->getOperand(1); 317566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *C = RHS; 318566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 319566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Does "C op A" simplify? 3200aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(Opcode, C, A, Q, MaxRecurse)) { 321566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // It does! Return "V op B" if it simplifies or is already available. 322566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // If V equals A then "V op B" is just the LHS. 323124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (V == A) return LHS; 324566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Otherwise return "V op B" if it simplifies. 3250aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *W = SimplifyBinOp(Opcode, V, B, Q, MaxRecurse)) { 326a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumReassoc; 327566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return W; 328a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 329566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands } 330566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands } 331566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 332566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Transform: "A op (B op C)" ==> "B op (C op A)" if it simplifies completely. 333566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands if (Op1 && Op1->getOpcode() == Opcode) { 334566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *A = LHS; 335566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *B = Op1->getOperand(0); 336566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands Value *C = Op1->getOperand(1); 337566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 338566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Does "C op A" simplify? 3390aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(Opcode, C, A, Q, MaxRecurse)) { 340566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // It does! Return "B op V" if it simplifies or is already available. 341566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // If V equals C then "B op V" is just the RHS. 342124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (V == C) return RHS; 343566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Otherwise return "B op V" if it simplifies. 3440aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *W = SimplifyBinOp(Opcode, B, V, Q, MaxRecurse)) { 345a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands ++NumReassoc; 346566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return W; 347a3c44a5280042dbc0cde995675c225ede4528c6eDuncan Sands } 348566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands } 349566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands } 350566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 351566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return 0; 352566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands} 353566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 354b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands/// ThreadBinOpOverSelect - In the case of a binary operation with a select 355b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands/// instruction as an operand, try to simplify the binop by seeing whether 356b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands/// evaluating it on both branches of the select results in the same value. 357b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands/// Returns the common value if so, otherwise returns null. 358b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sandsstatic Value *ThreadBinOpOverSelect(unsigned Opcode, Value *LHS, Value *RHS, 3590aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 3600312a93693abc2eb682b2b101c889959888fd883Duncan Sands // Recursion is always used, so bail out at once if we already hit the limit. 3610312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (!MaxRecurse--) 3620312a93693abc2eb682b2b101c889959888fd883Duncan Sands return 0; 3630312a93693abc2eb682b2b101c889959888fd883Duncan Sands 364b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands SelectInst *SI; 365b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands if (isa<SelectInst>(LHS)) { 366b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands SI = cast<SelectInst>(LHS); 367b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands } else { 368b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands assert(isa<SelectInst>(RHS) && "No select instruction operand!"); 369b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands SI = cast<SelectInst>(RHS); 370b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands } 371b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 372b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // Evaluate the BinOp on the true and false branches of the select. 373b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands Value *TV; 374b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands Value *FV; 375b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands if (SI == LHS) { 3760aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands TV = SimplifyBinOp(Opcode, SI->getTrueValue(), RHS, Q, MaxRecurse); 3770aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands FV = SimplifyBinOp(Opcode, SI->getFalseValue(), RHS, Q, MaxRecurse); 378b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands } else { 3790aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands TV = SimplifyBinOp(Opcode, LHS, SI->getTrueValue(), Q, MaxRecurse); 3800aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands FV = SimplifyBinOp(Opcode, LHS, SI->getFalseValue(), Q, MaxRecurse); 381b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands } 382b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 3837cf85e74e3885005ca8e5fdb155fa5351e255b85Duncan Sands // If they simplified to the same value, then return the common value. 384124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands // If they both failed to simplify then return null. 385124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (TV == FV) 386b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands return TV; 387b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 388b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // If one branch simplified to undef, return the other one. 389b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands if (TV && isa<UndefValue>(TV)) 390b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands return FV; 391b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands if (FV && isa<UndefValue>(FV)) 392b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands return TV; 393b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 394b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // If applying the operation did not change the true and false select values, 395b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // then the result of the binop is the select itself. 396124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (TV == SI->getTrueValue() && FV == SI->getFalseValue()) 397b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands return SI; 398b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 399b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // If one branch simplified and the other did not, and the simplified 400b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // value is equal to the unsimplified one, return the simplified value. 401b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // For example, select (cond, X, X & Z) & Z -> X & Z. 402b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands if ((FV && !TV) || (TV && !FV)) { 403b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // Check that the simplified value has the form "X op Y" where "op" is the 404b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // same as the original operation. 405b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands Instruction *Simplified = dyn_cast<Instruction>(FV ? FV : TV); 406b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands if (Simplified && Simplified->getOpcode() == Opcode) { 407b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // The value that didn't simplify is "UnsimplifiedLHS op UnsimplifiedRHS". 408b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // We already know that "op" is the same as for the simplified value. See 409b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // if the operands match too. If so, return the simplified value. 410b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands Value *UnsimplifiedBranch = FV ? SI->getTrueValue() : SI->getFalseValue(); 411b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands Value *UnsimplifiedLHS = SI == LHS ? UnsimplifiedBranch : LHS; 412b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands Value *UnsimplifiedRHS = SI == LHS ? RHS : UnsimplifiedBranch; 413124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (Simplified->getOperand(0) == UnsimplifiedLHS && 414124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands Simplified->getOperand(1) == UnsimplifiedRHS) 415b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands return Simplified; 416b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands if (Simplified->isCommutative() && 417124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands Simplified->getOperand(1) == UnsimplifiedLHS && 418124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands Simplified->getOperand(0) == UnsimplifiedRHS) 419b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands return Simplified; 420b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands } 421b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands } 422b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 423b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands return 0; 424b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands} 425b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 426b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands/// ThreadCmpOverSelect - In the case of a comparison with a select instruction, 427b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands/// try to simplify the comparison by seeing whether both branches of the select 428b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands/// result in the same value. Returns the common value if so, otherwise returns 429b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands/// null. 430b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sandsstatic Value *ThreadCmpOverSelect(CmpInst::Predicate Pred, Value *LHS, 4310aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Value *RHS, const Query &Q, 432a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands unsigned MaxRecurse) { 4330312a93693abc2eb682b2b101c889959888fd883Duncan Sands // Recursion is always used, so bail out at once if we already hit the limit. 4340312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (!MaxRecurse--) 4350312a93693abc2eb682b2b101c889959888fd883Duncan Sands return 0; 4360312a93693abc2eb682b2b101c889959888fd883Duncan Sands 437b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // Make sure the select is on the LHS. 438b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands if (!isa<SelectInst>(LHS)) { 439b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands std::swap(LHS, RHS); 440b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands Pred = CmpInst::getSwappedPredicate(Pred); 441b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands } 442b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands assert(isa<SelectInst>(LHS) && "Not comparing with a select instruction!"); 443b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands SelectInst *SI = cast<SelectInst>(LHS); 4446dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands Value *Cond = SI->getCondition(); 4456dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands Value *TV = SI->getTrueValue(); 4466dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands Value *FV = SI->getFalseValue(); 447b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 44850ca4d37f7f3b460c6441eb5ad14625a7d86b5d9Duncan Sands // Now that we have "cmp select(Cond, TV, FV), RHS", analyse it. 449b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // Does "cmp TV, RHS" simplify? 4500aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Value *TCmp = SimplifyCmpInst(Pred, TV, RHS, Q, MaxRecurse); 4516dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands if (TCmp == Cond) { 4526dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // It not only simplified, it simplified to the select condition. Replace 4536dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // it with 'true'. 4546dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands TCmp = getTrue(Cond->getType()); 4556dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands } else if (!TCmp) { 4566dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // It didn't simplify. However if "cmp TV, RHS" is equal to the select 4576dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // condition then we can replace it with 'true'. Otherwise give up. 4586dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands if (!isSameCompare(Cond, Pred, TV, RHS)) 4596dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands return 0; 4606dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands TCmp = getTrue(Cond->getType()); 46150ca4d37f7f3b460c6441eb5ad14625a7d86b5d9Duncan Sands } 46250ca4d37f7f3b460c6441eb5ad14625a7d86b5d9Duncan Sands 4636dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // Does "cmp FV, RHS" simplify? 4640aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Value *FCmp = SimplifyCmpInst(Pred, FV, RHS, Q, MaxRecurse); 4656dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands if (FCmp == Cond) { 4666dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // It not only simplified, it simplified to the select condition. Replace 4676dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // it with 'false'. 4686dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands FCmp = getFalse(Cond->getType()); 4696dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands } else if (!FCmp) { 4706dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // It didn't simplify. However if "cmp FV, RHS" is equal to the select 4716dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // condition then we can replace it with 'false'. Otherwise give up. 4726dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands if (!isSameCompare(Cond, Pred, FV, RHS)) 4736dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands return 0; 4746dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands FCmp = getFalse(Cond->getType()); 4756dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands } 4766dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands 4776dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // If both sides simplified to the same value, then use it as the result of 4786dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // the original comparison. 4796dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands if (TCmp == FCmp) 4806dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands return TCmp; 481aa97bb54f02784abefa0ae170af5937915bdb329Duncan Sands 482aa97bb54f02784abefa0ae170af5937915bdb329Duncan Sands // The remaining cases only make sense if the select condition has the same 483aa97bb54f02784abefa0ae170af5937915bdb329Duncan Sands // type as the result of the comparison, so bail out if this is not so. 484aa97bb54f02784abefa0ae170af5937915bdb329Duncan Sands if (Cond->getType()->isVectorTy() != RHS->getType()->isVectorTy()) 485aa97bb54f02784abefa0ae170af5937915bdb329Duncan Sands return 0; 4866dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // If the false value simplified to false, then the result of the compare 4876dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // is equal to "Cond && TCmp". This also catches the case when the false 4886dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // value simplified to false and the true value to true, returning "Cond". 4896dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands if (match(FCmp, m_Zero())) 4900aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyAndInst(Cond, TCmp, Q, MaxRecurse)) 4916dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands return V; 4926dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // If the true value simplified to true, then the result of the compare 4936dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // is equal to "Cond || FCmp". 4946dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands if (match(TCmp, m_One())) 4950aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyOrInst(Cond, FCmp, Q, MaxRecurse)) 4966dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands return V; 4976dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // Finally, if the false value simplified to true and the true value to 4986dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands // false, then the result of the compare is equal to "!Cond". 4996dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands if (match(FCmp, m_One()) && match(TCmp, m_Zero())) 5006dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands if (Value *V = 5016dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands SimplifyXorInst(Cond, Constant::getAllOnesValue(Cond->getType()), 5020aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse)) 5036dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands return V; 5046dc9e2bf7455fa1494078d5d52f1363b05183f20Duncan Sands 505b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands return 0; 506b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands} 507b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 508a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands/// ThreadBinOpOverPHI - In the case of a binary operation with an operand that 509a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands/// is a PHI instruction, try to simplify the binop by seeing whether evaluating 510a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands/// it on the incoming phi values yields the same result for every value. If so 511a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands/// returns the common value, otherwise returns null. 512a74a58c83be492b7d5b7383656f049909394cff4Duncan Sandsstatic Value *ThreadBinOpOverPHI(unsigned Opcode, Value *LHS, Value *RHS, 5130aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 5140312a93693abc2eb682b2b101c889959888fd883Duncan Sands // Recursion is always used, so bail out at once if we already hit the limit. 5150312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (!MaxRecurse--) 5160312a93693abc2eb682b2b101c889959888fd883Duncan Sands return 0; 5170312a93693abc2eb682b2b101c889959888fd883Duncan Sands 518a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands PHINode *PI; 519a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands if (isa<PHINode>(LHS)) { 520a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands PI = cast<PHINode>(LHS); 5211845009290e4d804ad377927bd8a08cca3036adcDuncan Sands // Bail out if RHS and the phi may be mutually interdependent due to a loop. 5220aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (!ValueDominatesPHI(RHS, PI, Q.DT)) 5231845009290e4d804ad377927bd8a08cca3036adcDuncan Sands return 0; 524a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands } else { 525a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands assert(isa<PHINode>(RHS) && "No PHI instruction operand!"); 526a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands PI = cast<PHINode>(RHS); 5271845009290e4d804ad377927bd8a08cca3036adcDuncan Sands // Bail out if LHS and the phi may be mutually interdependent due to a loop. 5280aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (!ValueDominatesPHI(LHS, PI, Q.DT)) 5291845009290e4d804ad377927bd8a08cca3036adcDuncan Sands return 0; 530a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands } 531a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 532a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // Evaluate the BinOp on the incoming phi values. 533a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands Value *CommonValue = 0; 534a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands for (unsigned i = 0, e = PI->getNumIncomingValues(); i != e; ++i) { 535552008946530e01efdad15044e1f621883d14a3aDuncan Sands Value *Incoming = PI->getIncomingValue(i); 536ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands // If the incoming value is the phi node itself, it can safely be skipped. 537552008946530e01efdad15044e1f621883d14a3aDuncan Sands if (Incoming == PI) continue; 538a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands Value *V = PI == LHS ? 5390aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands SimplifyBinOp(Opcode, Incoming, RHS, Q, MaxRecurse) : 5400aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands SimplifyBinOp(Opcode, LHS, Incoming, Q, MaxRecurse); 541a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // If the operation failed to simplify, or simplified to a different value 542a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // to previously, then give up. 543a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands if (!V || (CommonValue && V != CommonValue)) 544a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands return 0; 545a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands CommonValue = V; 546a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands } 547a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 548a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands return CommonValue; 549a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands} 550a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 551a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands/// ThreadCmpOverPHI - In the case of a comparison with a PHI instruction, try 552a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands/// try to simplify the comparison by seeing whether comparing with all of the 553a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands/// incoming phi values yields the same result every time. If so returns the 554a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands/// common result, otherwise returns null. 555a74a58c83be492b7d5b7383656f049909394cff4Duncan Sandsstatic Value *ThreadCmpOverPHI(CmpInst::Predicate Pred, Value *LHS, Value *RHS, 5560aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 5570312a93693abc2eb682b2b101c889959888fd883Duncan Sands // Recursion is always used, so bail out at once if we already hit the limit. 5580312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (!MaxRecurse--) 5590312a93693abc2eb682b2b101c889959888fd883Duncan Sands return 0; 5600312a93693abc2eb682b2b101c889959888fd883Duncan Sands 561a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // Make sure the phi is on the LHS. 562a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands if (!isa<PHINode>(LHS)) { 563a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands std::swap(LHS, RHS); 564a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands Pred = CmpInst::getSwappedPredicate(Pred); 565a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands } 566a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands assert(isa<PHINode>(LHS) && "Not comparing with a phi instruction!"); 567a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands PHINode *PI = cast<PHINode>(LHS); 568a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 5691845009290e4d804ad377927bd8a08cca3036adcDuncan Sands // Bail out if RHS and the phi may be mutually interdependent due to a loop. 5700aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (!ValueDominatesPHI(RHS, PI, Q.DT)) 5711845009290e4d804ad377927bd8a08cca3036adcDuncan Sands return 0; 5721845009290e4d804ad377927bd8a08cca3036adcDuncan Sands 573a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // Evaluate the BinOp on the incoming phi values. 574a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands Value *CommonValue = 0; 575a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands for (unsigned i = 0, e = PI->getNumIncomingValues(); i != e; ++i) { 576552008946530e01efdad15044e1f621883d14a3aDuncan Sands Value *Incoming = PI->getIncomingValue(i); 577ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands // If the incoming value is the phi node itself, it can safely be skipped. 578552008946530e01efdad15044e1f621883d14a3aDuncan Sands if (Incoming == PI) continue; 5790aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Value *V = SimplifyCmpInst(Pred, Incoming, RHS, Q, MaxRecurse); 580a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // If the operation failed to simplify, or simplified to a different value 581a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // to previously, then give up. 582a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands if (!V || (CommonValue && V != CommonValue)) 583a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands return 0; 584a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands CommonValue = V; 585a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands } 586a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 587a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands return CommonValue; 588a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands} 589a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 5908aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner/// SimplifyAddInst - Given operands for an Add, see if we can 591d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner/// fold the result. If not, this returns null. 592ee9a2e322af96accc9e55ed6373c0057453714b1Duncan Sandsstatic Value *SimplifyAddInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW, 5930aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 594d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (Constant *CLHS = dyn_cast<Constant>(Op0)) { 595d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (Constant *CRHS = dyn_cast<Constant>(Op1)) { 596d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner Constant *Ops[] = { CLHS, CRHS }; 5970aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ConstantFoldInstOperands(Instruction::Add, CLHS->getType(), Ops, 5980aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q.TD, Q.TLI); 5998aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner } 60012a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 6018aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner // Canonicalize the constant to the RHS. 6028aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner std::swap(Op0, Op1); 6038aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner } 60412a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 605fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // X + undef -> undef 606f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op1, m_Undef())) 607fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands return Op1; 60812a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 609fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // X + 0 -> X 610fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands if (match(Op1, m_Zero())) 611fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands return Op0; 612fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands 613fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // X + (Y - X) -> Y 614fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // (Y - X) + X -> Y 615ee9a2e322af96accc9e55ed6373c0057453714b1Duncan Sands // Eg: X + -X -> 0 616124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands Value *Y = 0; 617124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (match(Op1, m_Sub(m_Value(Y), m_Specific(Op0))) || 618124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands match(Op0, m_Sub(m_Value(Y), m_Specific(Op1)))) 619fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands return Y; 620fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands 621fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // X + ~X -> -1 since ~X = -X-1 622124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (match(Op0, m_Not(m_Specific(Op1))) || 623124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands match(Op1, m_Not(m_Specific(Op0)))) 624fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands return Constant::getAllOnesValue(Op0->getType()); 62587689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands 62682fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands /// i1 add -> xor. 62775d289ed6201e82718343d7a36d2a2fa082f6217Duncan Sands if (MaxRecurse && Op0->getType()->isIntegerTy(1)) 6280aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyXorInst(Op0, Op1, Q, MaxRecurse-1)) 62907f30fbd734069b80b90c6aeea0ae645ce3880c0Duncan Sands return V; 63082fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 631566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Try some generic simplifications for associative operations. 6320aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyAssociativeBinOp(Instruction::Add, Op0, Op1, Q, 633566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands MaxRecurse)) 634566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return V; 635566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 6363421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Mul distributes over Add. Try some generic simplifications based on this. 6373421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (Value *V = FactorizeBinOp(Instruction::Add, Op0, Op1, Instruction::Mul, 6380aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse)) 6393421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return V; 6403421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 64187689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // Threading Add over selects and phi nodes is pointless, so don't bother. 64287689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // Threading over the select in "A + select(cond, B, C)" means evaluating 64387689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // "A+B" and "A+C" and seeing if they are equal; but they are equal if and 64487689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // only if B and C are equal. If B and C are equal then (since we assume 64587689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // that operands have already been simplified) "select(cond, B, C)" should 64687689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // have been simplified to the common value of B and C already. Analysing 64787689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // "A+B" and "A+C" thus gains nothing, but costs compile time. Similarly 64887689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // for threading over phi nodes. 64987689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands 6508aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner return 0; 6518aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner} 6528aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner 653ee9a2e322af96accc9e55ed6373c0057453714b1Duncan SandsValue *llvm::SimplifyAddInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW, 6543574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, const TargetLibraryInfo *TLI, 655618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const DominatorTree *DT) { 6560aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyAddInst(Op0, Op1, isNSW, isNUW, Query (TD, TLI, DT), 6570aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RecursionLimit); 658ee9a2e322af96accc9e55ed6373c0057453714b1Duncan Sands} 659ee9a2e322af96accc9e55ed6373c0057453714b1Duncan Sands 660fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth/// \brief Compute the base pointer and cumulative constant offsets for V. 661fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth/// 662fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth/// This strips all constant offsets off of V, leaving it the base pointer, and 663fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth/// accumulates the total constant offset applied in the returned constant. It 664fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth/// returns 0 if V is not a pointer, and returns the constant '0' if there are 665fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth/// no constant offsets applied. 6663574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmowstatic Constant *stripAndComputeConstantOffsets(const DataLayout &TD, 667fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth Value *&V) { 668fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth if (!V->getType()->isPointerTy()) 669fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth return 0; 670fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth 671426c2bf5cdd2173e4a33aea8cb92cf684a724f4bChandler Carruth unsigned IntPtrWidth = TD.getPointerSizeInBits(); 67290c14fcb7ea3436a8b3053f8a9aa529c03011d34Chandler Carruth APInt Offset = APInt::getNullValue(IntPtrWidth); 673fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth 674fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth // Even though we don't look through PHI nodes, we could be called on an 675fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth // instruction in an unreachable block, which may be on a cycle. 676fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth SmallPtrSet<Value *, 4> Visited; 677fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth Visited.insert(V); 678fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth do { 679fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) { 6807550f96b2f3a5e187f737ddad45563962fbd509cChandler Carruth if (!GEP->isInBounds() || !GEP->accumulateConstantOffset(TD, Offset)) 681fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth break; 682fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth V = GEP->getPointerOperand(); 683fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth } else if (Operator::getOpcode(V) == Instruction::BitCast) { 684fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth V = cast<Operator>(V)->getOperand(0); 685fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth } else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) { 686fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth if (GA->mayBeOverridden()) 687fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth break; 688fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth V = GA->getAliasee(); 689fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth } else { 690fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth break; 691fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth } 692fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth assert(V->getType()->isPointerTy() && "Unexpected operand type!"); 693fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth } while (Visited.insert(V)); 694fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth 695ece6c6bb6329748b92403c06ac87f45c43485911Chandler Carruth Type *IntPtrTy = TD.getIntPtrType(V->getContext()); 69690c14fcb7ea3436a8b3053f8a9aa529c03011d34Chandler Carruth return ConstantInt::get(IntPtrTy, Offset); 697fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth} 698fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth 699fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth/// \brief Compute the constant difference between two pointer values. 700fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth/// If the difference is not a constant, returns zero. 7013574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmowstatic Constant *computePointerDifference(const DataLayout &TD, 702fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth Value *LHS, Value *RHS) { 703fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth Constant *LHSOffset = stripAndComputeConstantOffsets(TD, LHS); 704fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth if (!LHSOffset) 705fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth return 0; 706fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth Constant *RHSOffset = stripAndComputeConstantOffsets(TD, RHS); 707fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth if (!RHSOffset) 708fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth return 0; 709fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth 710fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth // If LHS and RHS are not related via constant offsets to the same base 711fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth // value, there is nothing we can do here. 712fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth if (LHS != RHS) 713fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth return 0; 714fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth 715fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth // Otherwise, the difference of LHS - RHS can be computed as: 716fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth // LHS - RHS 717fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth // = (LHSOffset + Base) - (RHSOffset + Base) 718fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth // = LHSOffset - RHSOffset 719fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth return ConstantExpr::getSub(LHSOffset, RHSOffset); 720fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth} 721fc72ae613afd7ca2526bb66156bafe8b0054cb3bChandler Carruth 722fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands/// SimplifySubInst - Given operands for a Sub, see if we can 723fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands/// fold the result. If not, this returns null. 724ee9a2e322af96accc9e55ed6373c0057453714b1Duncan Sandsstatic Value *SimplifySubInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW, 7250aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 726fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands if (Constant *CLHS = dyn_cast<Constant>(Op0)) 727fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands if (Constant *CRHS = dyn_cast<Constant>(Op1)) { 728fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands Constant *Ops[] = { CLHS, CRHS }; 729fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands return ConstantFoldInstOperands(Instruction::Sub, CLHS->getType(), 7300aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Ops, Q.TD, Q.TLI); 731fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands } 732fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands 733fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // X - undef -> undef 734fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // undef - X -> undef 735f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op0, m_Undef()) || match(Op1, m_Undef())) 736fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands return UndefValue::get(Op0->getType()); 737fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands 738fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // X - 0 -> X 739fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands if (match(Op1, m_Zero())) 740fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands return Op0; 741fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands 742fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // X - X -> 0 743124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (Op0 == Op1) 744fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands return Constant::getNullValue(Op0->getType()); 745fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands 746fe02c69f84ad52d42be934e4fe702f03e4991a6aDuncan Sands // (X*2) - X -> X 747fe02c69f84ad52d42be934e4fe702f03e4991a6aDuncan Sands // (X<<1) - X -> X 748b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands Value *X = 0; 749fe02c69f84ad52d42be934e4fe702f03e4991a6aDuncan Sands if (match(Op0, m_Mul(m_Specific(Op1), m_ConstantInt<2>())) || 750fe02c69f84ad52d42be934e4fe702f03e4991a6aDuncan Sands match(Op0, m_Shl(m_Specific(Op1), m_One()))) 751fe02c69f84ad52d42be934e4fe702f03e4991a6aDuncan Sands return Op1; 752fe02c69f84ad52d42be934e4fe702f03e4991a6aDuncan Sands 753b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // (X + Y) - Z -> X + (Y - Z) or Y + (X - Z) if everything simplifies. 754b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // For example, (X + Y) - Y -> X; (Y + X) - Y -> X 755b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands Value *Y = 0, *Z = Op1; 756b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands if (MaxRecurse && match(Op0, m_Add(m_Value(X), m_Value(Y)))) { // (X + Y) - Z 757b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // See if "V === Y - Z" simplifies. 7580aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(Instruction::Sub, Y, Z, Q, MaxRecurse-1)) 759b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // It does! Now see if "X + V" simplifies. 7600aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *W = SimplifyBinOp(Instruction::Add, X, V, Q, MaxRecurse-1)) { 761b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // It does, we successfully reassociated! 762b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands ++NumReassoc; 763b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands return W; 764b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands } 765b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // See if "V === X - Z" simplifies. 7660aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(Instruction::Sub, X, Z, Q, MaxRecurse-1)) 767b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // It does! Now see if "Y + V" simplifies. 7680aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *W = SimplifyBinOp(Instruction::Add, Y, V, Q, MaxRecurse-1)) { 769b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // It does, we successfully reassociated! 770b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands ++NumReassoc; 771b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands return W; 772b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands } 773b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands } 77482fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 775b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // X - (Y + Z) -> (X - Y) - Z or (X - Z) - Y if everything simplifies. 776b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // For example, X - (X + 1) -> -1 777b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands X = Op0; 778b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands if (MaxRecurse && match(Op1, m_Add(m_Value(Y), m_Value(Z)))) { // X - (Y + Z) 779b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // See if "V === X - Y" simplifies. 7800aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(Instruction::Sub, X, Y, Q, MaxRecurse-1)) 781b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // It does! Now see if "V - Z" simplifies. 7820aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *W = SimplifyBinOp(Instruction::Sub, V, Z, Q, MaxRecurse-1)) { 783b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // It does, we successfully reassociated! 784b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands ++NumReassoc; 785b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands return W; 786b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands } 787b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // See if "V === X - Z" simplifies. 7880aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(Instruction::Sub, X, Z, Q, MaxRecurse-1)) 789b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // It does! Now see if "V - Y" simplifies. 7900aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *W = SimplifyBinOp(Instruction::Sub, V, Y, Q, MaxRecurse-1)) { 791b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // It does, we successfully reassociated! 792b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands ++NumReassoc; 793b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands return W; 794b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands } 795b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands } 796b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands 797b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // Z - (X - Y) -> (Z - X) + Y if everything simplifies. 798b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // For example, X - (X - Y) -> Y. 799b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands Z = Op0; 800c087e20331c8a4c3b77d96a73588e80c06d89e3dDuncan Sands if (MaxRecurse && match(Op1, m_Sub(m_Value(X), m_Value(Y)))) // Z - (X - Y) 801c087e20331c8a4c3b77d96a73588e80c06d89e3dDuncan Sands // See if "V === Z - X" simplifies. 8020aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyBinOp(Instruction::Sub, Z, X, Q, MaxRecurse-1)) 803b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // It does! Now see if "V + Y" simplifies. 8040aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *W = SimplifyBinOp(Instruction::Add, V, Y, Q, MaxRecurse-1)) { 805c087e20331c8a4c3b77d96a73588e80c06d89e3dDuncan Sands // It does, we successfully reassociated! 806c087e20331c8a4c3b77d96a73588e80c06d89e3dDuncan Sands ++NumReassoc; 807c087e20331c8a4c3b77d96a73588e80c06d89e3dDuncan Sands return W; 808c087e20331c8a4c3b77d96a73588e80c06d89e3dDuncan Sands } 809c087e20331c8a4c3b77d96a73588e80c06d89e3dDuncan Sands 810bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands // trunc(X) - trunc(Y) -> trunc(X - Y) if everything simplifies. 811bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands if (MaxRecurse && match(Op0, m_Trunc(m_Value(X))) && 812bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands match(Op1, m_Trunc(m_Value(Y)))) 813bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands if (X->getType() == Y->getType()) 814bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands // See if "V === X - Y" simplifies. 815bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands if (Value *V = SimplifyBinOp(Instruction::Sub, X, Y, Q, MaxRecurse-1)) 816bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands // It does! Now see if "trunc V" simplifies. 817bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands if (Value *W = SimplifyTruncInst(V, Op0->getType(), Q, MaxRecurse-1)) 818bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands // It does, return the simplified "trunc V". 819bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands return W; 820bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands 821bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands // Variations on GEP(base, I, ...) - GEP(base, i, ...) -> GEP(null, I-i, ...). 822bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands if (Q.TD && match(Op0, m_PtrToInt(m_Value(X))) && 823bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands match(Op1, m_PtrToInt(m_Value(Y)))) 824bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands if (Constant *Result = computePointerDifference(*Q.TD, X, Y)) 825bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands return ConstantExpr::getIntegerCast(Result, Op0->getType(), true); 826bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands 8273421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Mul distributes over Sub. Try some generic simplifications based on this. 8283421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (Value *V = FactorizeBinOp(Instruction::Sub, Op0, Op1, Instruction::Mul, 8290aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse)) 8303421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return V; 8313421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 832b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands // i1 sub -> xor. 833b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands if (MaxRecurse && Op0->getType()->isIntegerTy(1)) 8340aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyXorInst(Op0, Op1, Q, MaxRecurse-1)) 835b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands return V; 836b2f3c383ec62b959ee27d0a5fb890894c4e49e86Duncan Sands 837fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // Threading Sub over selects and phi nodes is pointless, so don't bother. 838fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // Threading over the select in "A - select(cond, B, C)" means evaluating 839fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // "A-B" and "A-C" and seeing if they are equal; but they are equal if and 840fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // only if B and C are equal. If B and C are equal then (since we assume 841fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // that operands have already been simplified) "select(cond, B, C)" should 842fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // have been simplified to the common value of B and C already. Analysing 843fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // "A-B" and "A-C" thus gains nothing, but costs compile time. Similarly 844fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands // for threading over phi nodes. 845fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands 846fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands return 0; 847fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands} 848fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands 849ee9a2e322af96accc9e55ed6373c0057453714b1Duncan SandsValue *llvm::SimplifySubInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW, 8503574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, const TargetLibraryInfo *TLI, 851618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const DominatorTree *DT) { 8520aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifySubInst(Op0, Op1, isNSW, isNUW, Query (TD, TLI, DT), 8530aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RecursionLimit); 854ee9a2e322af96accc9e55ed6373c0057453714b1Duncan Sands} 855ee9a2e322af96accc9e55ed6373c0057453714b1Duncan Sands 85609ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman/// Given operands for an FAdd, see if we can fold the result. If not, this 85709ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman/// returns null. 85809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilsemanstatic Value *SimplifyFAddInst(Value *Op0, Value *Op1, FastMathFlags FMF, 85909ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman const Query &Q, unsigned MaxRecurse) { 86009ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (Constant *CLHS = dyn_cast<Constant>(Op0)) { 86109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (Constant *CRHS = dyn_cast<Constant>(Op1)) { 86209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman Constant *Ops[] = { CLHS, CRHS }; 86309ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return ConstantFoldInstOperands(Instruction::FAdd, CLHS->getType(), 86409ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman Ops, Q.TD, Q.TLI); 86509ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman } 86609ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 86709ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // Canonicalize the constant to the RHS. 86809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman std::swap(Op0, Op1); 86909ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman } 87009ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 87109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // fadd X, -0 ==> X 87209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (match(Op1, m_NegZero())) 87309ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return Op0; 87409ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 87509ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // fadd X, 0 ==> X, when we know X is not -0 87609ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (match(Op1, m_Zero()) && 87709ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman (FMF.noSignedZeros() || CannotBeNegativeZero(Op0))) 87809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return Op0; 87909ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 88009ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // fadd [nnan ninf] X, (fsub [nnan ninf] 0, X) ==> 0 88109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // where nnan and ninf have to occur at least once somewhere in this 88209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // expression 88309ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman Value *SubOp = 0; 88409ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (match(Op1, m_FSub(m_AnyZero(), m_Specific(Op0)))) 88509ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman SubOp = Op1; 88609ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman else if (match(Op0, m_FSub(m_AnyZero(), m_Specific(Op1)))) 88709ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman SubOp = Op0; 88809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (SubOp) { 88909ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman Instruction *FSub = cast<Instruction>(SubOp); 89009ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if ((FMF.noNaNs() || FSub->hasNoNaNs()) && 89109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman (FMF.noInfs() || FSub->hasNoInfs())) 89209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return Constant::getNullValue(Op0->getType()); 89309ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman } 89409ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 89509ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return 0; 89609ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman} 89709ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 89809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman/// Given operands for an FSub, see if we can fold the result. If not, this 89909ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman/// returns null. 90009ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilsemanstatic Value *SimplifyFSubInst(Value *Op0, Value *Op1, FastMathFlags FMF, 90109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman const Query &Q, unsigned MaxRecurse) { 90209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (Constant *CLHS = dyn_cast<Constant>(Op0)) { 90309ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (Constant *CRHS = dyn_cast<Constant>(Op1)) { 90409ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman Constant *Ops[] = { CLHS, CRHS }; 90509ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return ConstantFoldInstOperands(Instruction::FSub, CLHS->getType(), 90609ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman Ops, Q.TD, Q.TLI); 90709ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman } 90809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman } 90909ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 91009ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // fsub X, 0 ==> X 91109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (match(Op1, m_Zero())) 91209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return Op0; 91309ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 91409ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // fsub X, -0 ==> X, when we know X is not -0 91509ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (match(Op1, m_NegZero()) && 91609ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman (FMF.noSignedZeros() || CannotBeNegativeZero(Op0))) 91709ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return Op0; 91809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 91909ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // fsub 0, (fsub -0.0, X) ==> X 92009ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman Value *X; 92109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (match(Op0, m_AnyZero())) { 92209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (match(Op1, m_FSub(m_NegZero(), m_Value(X)))) 92309ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return X; 92409ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (FMF.noSignedZeros() && match(Op1, m_FSub(m_AnyZero(), m_Value(X)))) 92509ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return X; 92609ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman } 92709ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 92809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // fsub nnan ninf x, x ==> 0.0 92909ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (FMF.noNaNs() && FMF.noInfs() && Op0 == Op1) 93009ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return Constant::getNullValue(Op0->getType()); 93109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 93209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return 0; 93309ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman} 93409ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 935eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman/// Given the operands for an FMul, see if we can fold the result 936eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilsemanstatic Value *SimplifyFMulInst(Value *Op0, Value *Op1, 937eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman FastMathFlags FMF, 938eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman const Query &Q, 939eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman unsigned MaxRecurse) { 940eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman if (Constant *CLHS = dyn_cast<Constant>(Op0)) { 941eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman if (Constant *CRHS = dyn_cast<Constant>(Op1)) { 942eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman Constant *Ops[] = { CLHS, CRHS }; 943eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman return ConstantFoldInstOperands(Instruction::FMul, CLHS->getType(), 944eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman Ops, Q.TD, Q.TLI); 945eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman } 946eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman 94709ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // Canonicalize the constant to the RHS. 94809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman std::swap(Op0, Op1); 949eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman } 950eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman 95109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // fmul X, 1.0 ==> X 95209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (match(Op1, m_FPOne())) 95309ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return Op0; 95409ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 95509ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman // fmul nnan nsz X, 0 ==> 0 95609ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman if (FMF.noNaNs() && FMF.noSignedZeros() && match(Op1, m_AnyZero())) 95709ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return Op1; 95809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 959eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman return 0; 960eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman} 961eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman 96282fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands/// SimplifyMulInst - Given operands for a Mul, see if we can 96382fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands/// fold the result. If not, this returns null. 9640aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyMulInst(Value *Op0, Value *Op1, const Query &Q, 9650aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands unsigned MaxRecurse) { 96682fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands if (Constant *CLHS = dyn_cast<Constant>(Op0)) { 96782fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands if (Constant *CRHS = dyn_cast<Constant>(Op1)) { 96882fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands Constant *Ops[] = { CLHS, CRHS }; 96982fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands return ConstantFoldInstOperands(Instruction::Mul, CLHS->getType(), 9700aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Ops, Q.TD, Q.TLI); 97182fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands } 97282fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 97382fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands // Canonicalize the constant to the RHS. 97482fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands std::swap(Op0, Op1); 97582fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands } 97682fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 97782fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands // X * undef -> 0 978f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op1, m_Undef())) 97982fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands return Constant::getNullValue(Op0->getType()); 98082fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 98182fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands // X * 0 -> 0 98282fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands if (match(Op1, m_Zero())) 98382fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands return Op1; 98482fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 98582fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands // X * 1 -> X 98682fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands if (match(Op1, m_One())) 98782fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands return Op0; 98882fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 9891895e98ef38afbe011575cc25f4889d96e37421bDuncan Sands // (X / Y) * Y -> X if the division is exact. 99055c6d57734cd2f141dc2d6912fc22746d5eeae54Benjamin Kramer Value *X = 0; 99155c6d57734cd2f141dc2d6912fc22746d5eeae54Benjamin Kramer if (match(Op0, m_Exact(m_IDiv(m_Value(X), m_Specific(Op1)))) || // (X / Y) * Y 99255c6d57734cd2f141dc2d6912fc22746d5eeae54Benjamin Kramer match(Op1, m_Exact(m_IDiv(m_Value(X), m_Specific(Op0))))) // Y * (X / Y) 99355c6d57734cd2f141dc2d6912fc22746d5eeae54Benjamin Kramer return X; 9941895e98ef38afbe011575cc25f4889d96e37421bDuncan Sands 9955413880654585f01ea9880f24f07f27c8da56ba8Nick Lewycky // i1 mul -> and. 99675d289ed6201e82718343d7a36d2a2fa082f6217Duncan Sands if (MaxRecurse && Op0->getType()->isIntegerTy(1)) 9970aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyAndInst(Op0, Op1, Q, MaxRecurse-1)) 99807f30fbd734069b80b90c6aeea0ae645ce3880c0Duncan Sands return V; 99982fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 100082fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands // Try some generic simplifications for associative operations. 10010aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyAssociativeBinOp(Instruction::Mul, Op0, Op1, Q, 100282fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands MaxRecurse)) 100382fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands return V; 100482fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 100582fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands // Mul distributes over Add. Try some generic simplifications based on this. 100682fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands if (Value *V = ExpandBinOp(Instruction::Mul, Op0, Op1, Instruction::Add, 10070aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse)) 100882fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands return V; 100982fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 101082fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands // If the operation is with the result of a select instruction, check whether 101182fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands // operating on either branch of the select always yields the same value. 101282fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands if (isa<SelectInst>(Op0) || isa<SelectInst>(Op1)) 10130aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverSelect(Instruction::Mul, Op0, Op1, Q, 101482fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands MaxRecurse)) 101582fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands return V; 101682fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 101782fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands // If the operation is with the result of a phi instruction, check whether 101882fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands // operating on all incoming values of the phi always yields the same value. 101982fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands if (isa<PHINode>(Op0) || isa<PHINode>(Op1)) 10200aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverPHI(Instruction::Mul, Op0, Op1, Q, 102182fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands MaxRecurse)) 102282fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands return V; 102382fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 102482fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands return 0; 102582fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands} 102682fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 102709ee250e728ccdb7afc6354d777f8319c5a0465cMichael IlsemanValue *llvm::SimplifyFAddInst(Value *Op0, Value *Op1, FastMathFlags FMF, 102809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman const DataLayout *TD, const TargetLibraryInfo *TLI, 102909ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman const DominatorTree *DT) { 103009ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return ::SimplifyFAddInst(Op0, Op1, FMF, Query (TD, TLI, DT), RecursionLimit); 103109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman} 103209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 103309ee250e728ccdb7afc6354d777f8319c5a0465cMichael IlsemanValue *llvm::SimplifyFSubInst(Value *Op0, Value *Op1, FastMathFlags FMF, 103409ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman const DataLayout *TD, const TargetLibraryInfo *TLI, 103509ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman const DominatorTree *DT) { 103609ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman return ::SimplifyFSubInst(Op0, Op1, FMF, Query (TD, TLI, DT), RecursionLimit); 103709ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman} 103809ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman 1039eb61c920f12cacee38815bf10821d2f294b66f3aMichael IlsemanValue *llvm::SimplifyFMulInst(Value *Op0, Value *Op1, 1040eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman FastMathFlags FMF, 1041eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman const DataLayout *TD, 1042eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman const TargetLibraryInfo *TLI, 1043eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman const DominatorTree *DT) { 1044eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman return ::SimplifyFMulInst(Op0, Op1, FMF, Query (TD, TLI, DT), RecursionLimit); 1045eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman} 1046eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman 10473574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifyMulInst(Value *Op0, Value *Op1, const DataLayout *TD, 1048618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 104982fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands const DominatorTree *DT) { 10500aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyMulInst(Op0, Op1, Query (TD, TLI, DT), RecursionLimit); 105182fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands} 105282fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands 1053593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands/// SimplifyDiv - Given operands for an SDiv or UDiv, see if we can 1054593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands/// fold the result. If not, this returns null. 1055479b4b9ef06dd84097202ffa6aea07913cdf651cAnders Carlssonstatic Value *SimplifyDiv(Instruction::BinaryOps Opcode, Value *Op0, Value *Op1, 10560aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 1057593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands if (Constant *C0 = dyn_cast<Constant>(Op0)) { 1058593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands if (Constant *C1 = dyn_cast<Constant>(Op1)) { 1059593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands Constant *Ops[] = { C0, C1 }; 10600aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ConstantFoldInstOperands(Opcode, C0->getType(), Ops, Q.TD, Q.TLI); 1061593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands } 1062593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands } 1063593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1064a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands bool isSigned = Opcode == Instruction::SDiv; 1065a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands 1066593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands // X / undef -> undef 1067f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op1, m_Undef())) 1068593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return Op1; 1069593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1070593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands // undef / X -> 0 1071f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op0, m_Undef())) 1072593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return Constant::getNullValue(Op0->getType()); 1073593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1074593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands // 0 / X -> 0, we don't need to preserve faults! 1075593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands if (match(Op0, m_Zero())) 1076593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return Op0; 1077593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1078593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands // X / 1 -> X 1079593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands if (match(Op1, m_One())) 1080593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return Op0; 1081593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1082593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands if (Op0->getType()->isIntegerTy(1)) 1083593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands // It can't be division by zero, hence it must be division by one. 1084593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return Op0; 1085593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1086593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands // X / X -> 1 1087593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands if (Op0 == Op1) 1088593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return ConstantInt::get(Op0->getType(), 1); 1089593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1090593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands // (X * Y) / Y -> X if the multiplication does not overflow. 1091593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands Value *X = 0, *Y = 0; 1092593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands if (match(Op0, m_Mul(m_Value(X), m_Value(Y))) && (X == Op1 || Y == Op1)) { 1093593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands if (Y != Op1) std::swap(X, Y); // Ensure expression is (X * Y) / Y, Y = Op1 109432a43cc0fc3cd42702d7859eaa58dd42f561a54dDuncan Sands OverflowingBinaryOperator *Mul = cast<OverflowingBinaryOperator>(Op0); 10954b720718fbda1194f925e0a9d931bc220e8b0e3aDuncan Sands // If the Mul knows it does not overflow, then we are good to go. 10964b720718fbda1194f925e0a9d931bc220e8b0e3aDuncan Sands if ((isSigned && Mul->hasNoSignedWrap()) || 10974b720718fbda1194f925e0a9d931bc220e8b0e3aDuncan Sands (!isSigned && Mul->hasNoUnsignedWrap())) 10984b720718fbda1194f925e0a9d931bc220e8b0e3aDuncan Sands return X; 1099593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands // If X has the form X = A / Y then X * Y cannot overflow. 1100593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands if (BinaryOperator *Div = dyn_cast<BinaryOperator>(X)) 1101593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands if (Div->getOpcode() == Opcode && Div->getOperand(1) == Y) 1102593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return X; 1103593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands } 1104593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1105a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands // (X rem Y) / Y -> 0 1106a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands if ((isSigned && match(Op0, m_SRem(m_Value(), m_Specific(Op1)))) || 1107a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands (!isSigned && match(Op0, m_URem(m_Value(), m_Specific(Op1))))) 1108a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands return Constant::getNullValue(Op0->getType()); 1109a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands 1110a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands // If the operation is with the result of a select instruction, check whether 1111a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands // operating on either branch of the select always yields the same value. 1112a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands if (isa<SelectInst>(Op0) || isa<SelectInst>(Op1)) 11130aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverSelect(Opcode, Op0, Op1, Q, MaxRecurse)) 1114a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands return V; 1115a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands 1116a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands // If the operation is with the result of a phi instruction, check whether 1117a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands // operating on all incoming values of the phi always yields the same value. 1118a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands if (isa<PHINode>(Op0) || isa<PHINode>(Op1)) 11190aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverPHI(Opcode, Op0, Op1, Q, MaxRecurse)) 1120a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands return V; 1121a3e292c7e85efb33899f08238f57a85996a05a0bDuncan Sands 1122593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return 0; 1123593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands} 1124593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1125593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands/// SimplifySDivInst - Given operands for an SDiv, see if we can 1126593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands/// fold the result. If not, this returns null. 11270aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifySDivInst(Value *Op0, Value *Op1, const Query &Q, 11280aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands unsigned MaxRecurse) { 11290aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyDiv(Instruction::SDiv, Op0, Op1, Q, MaxRecurse)) 1130593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return V; 1131593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1132593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return 0; 1133593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands} 1134593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 11353574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifySDivInst(Value *Op0, Value *Op1, const DataLayout *TD, 1136618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 11371fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel const DominatorTree *DT) { 11380aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifySDivInst(Op0, Op1, Query (TD, TLI, DT), RecursionLimit); 1139593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands} 1140593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1141593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands/// SimplifyUDivInst - Given operands for a UDiv, see if we can 1142593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands/// fold the result. If not, this returns null. 11430aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyUDivInst(Value *Op0, Value *Op1, const Query &Q, 11440aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands unsigned MaxRecurse) { 11450aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyDiv(Instruction::UDiv, Op0, Op1, Q, MaxRecurse)) 1146593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return V; 1147593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 1148593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands return 0; 1149593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands} 1150593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 11513574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifyUDivInst(Value *Op0, Value *Op1, const DataLayout *TD, 1152618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 11531fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel const DominatorTree *DT) { 11540aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyUDivInst(Op0, Op1, Query (TD, TLI, DT), RecursionLimit); 1155593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands} 1156593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands 11570aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyFDivInst(Value *Op0, Value *Op1, const Query &Q, 11580aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands unsigned) { 11591fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel // undef / X -> undef (the undef could be a snan). 1160f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op0, m_Undef())) 11611fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel return Op0; 11621fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel 11631fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel // X / undef -> undef 1164f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op1, m_Undef())) 11651fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel return Op1; 11661fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel 11671fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel return 0; 11681fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel} 11691fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel 11703574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifyFDivInst(Value *Op0, Value *Op1, const DataLayout *TD, 1171618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 11721fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel const DominatorTree *DT) { 11730aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyFDivInst(Op0, Op1, Query (TD, TLI, DT), RecursionLimit); 11741fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel} 11751fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel 1176f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands/// SimplifyRem - Given operands for an SRem or URem, see if we can 1177f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands/// fold the result. If not, this returns null. 1178f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sandsstatic Value *SimplifyRem(Instruction::BinaryOps Opcode, Value *Op0, Value *Op1, 11790aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 1180f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (Constant *C0 = dyn_cast<Constant>(Op0)) { 1181f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (Constant *C1 = dyn_cast<Constant>(Op1)) { 1182f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands Constant *Ops[] = { C0, C1 }; 11830aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ConstantFoldInstOperands(Opcode, C0->getType(), Ops, Q.TD, Q.TLI); 1184f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands } 1185f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands } 1186f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1187f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // X % undef -> undef 1188f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (match(Op1, m_Undef())) 1189f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return Op1; 1190f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1191f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // undef % X -> 0 1192f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (match(Op0, m_Undef())) 1193f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return Constant::getNullValue(Op0->getType()); 1194f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1195f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // 0 % X -> 0, we don't need to preserve faults! 1196f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (match(Op0, m_Zero())) 1197f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return Op0; 1198f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1199f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // X % 0 -> undef, we don't need to preserve faults! 1200f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (match(Op1, m_Zero())) 1201f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return UndefValue::get(Op0->getType()); 1202f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1203f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // X % 1 -> 0 1204f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (match(Op1, m_One())) 1205f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return Constant::getNullValue(Op0->getType()); 1206f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1207f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (Op0->getType()->isIntegerTy(1)) 1208f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // It can't be remainder by zero, hence it must be remainder by one. 1209f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return Constant::getNullValue(Op0->getType()); 1210f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1211f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // X % X -> 0 1212f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (Op0 == Op1) 1213f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return Constant::getNullValue(Op0->getType()); 1214f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1215f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // If the operation is with the result of a select instruction, check whether 1216f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // operating on either branch of the select always yields the same value. 1217f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (isa<SelectInst>(Op0) || isa<SelectInst>(Op1)) 12180aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverSelect(Opcode, Op0, Op1, Q, MaxRecurse)) 1219f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return V; 1220f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1221f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // If the operation is with the result of a phi instruction, check whether 1222f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // operating on all incoming values of the phi always yields the same value. 1223f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (isa<PHINode>(Op0) || isa<PHINode>(Op1)) 12240aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverPHI(Opcode, Op0, Op1, Q, MaxRecurse)) 1225f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return V; 1226f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1227f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return 0; 1228f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands} 1229f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1230f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands/// SimplifySRemInst - Given operands for an SRem, see if we can 1231f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands/// fold the result. If not, this returns null. 12320aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifySRemInst(Value *Op0, Value *Op1, const Query &Q, 12330aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands unsigned MaxRecurse) { 12340aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyRem(Instruction::SRem, Op0, Op1, Q, MaxRecurse)) 1235f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return V; 1236f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1237f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return 0; 1238f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands} 1239f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 12403574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifySRemInst(Value *Op0, Value *Op1, const DataLayout *TD, 1241618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 1242f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands const DominatorTree *DT) { 12430aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifySRemInst(Op0, Op1, Query (TD, TLI, DT), RecursionLimit); 1244f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands} 1245f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1246f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands/// SimplifyURemInst - Given operands for a URem, see if we can 1247f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands/// fold the result. If not, this returns null. 12480aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyURemInst(Value *Op0, Value *Op1, const Query &Q, 1249618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier unsigned MaxRecurse) { 12500aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyRem(Instruction::URem, Op0, Op1, Q, MaxRecurse)) 1251f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return V; 1252f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1253f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return 0; 1254f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands} 1255f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 12563574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifyURemInst(Value *Op0, Value *Op1, const DataLayout *TD, 1257618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 1258f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands const DominatorTree *DT) { 12590aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyURemInst(Op0, Op1, Query (TD, TLI, DT), RecursionLimit); 1260f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands} 1261f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 12620aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyFRemInst(Value *Op0, Value *Op1, const Query &, 1263618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier unsigned) { 1264f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // undef % X -> undef (the undef could be a snan). 1265f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (match(Op0, m_Undef())) 1266f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return Op0; 1267f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1268f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands // X % undef -> undef 1269f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands if (match(Op1, m_Undef())) 1270f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return Op1; 1271f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1272f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands return 0; 1273f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands} 1274f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 12753574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifyFRemInst(Value *Op0, Value *Op1, const DataLayout *TD, 1276618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 1277f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands const DominatorTree *DT) { 12780aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyFRemInst(Op0, Op1, Query (TD, TLI, DT), RecursionLimit); 1279f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands} 1280f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands 1281cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands/// SimplifyShift - Given operands for an Shl, LShr or AShr, see if we can 1282c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands/// fold the result. If not, this returns null. 1283cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sandsstatic Value *SimplifyShift(unsigned Opcode, Value *Op0, Value *Op1, 12840aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 1285c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands if (Constant *C0 = dyn_cast<Constant>(Op0)) { 1286c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands if (Constant *C1 = dyn_cast<Constant>(Op1)) { 1287c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands Constant *Ops[] = { C0, C1 }; 12880aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ConstantFoldInstOperands(Opcode, C0->getType(), Ops, Q.TD, Q.TLI); 1289c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands } 1290c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands } 1291c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 1292cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands // 0 shift by X -> 0 1293c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands if (match(Op0, m_Zero())) 1294c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands return Op0; 1295c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 1296cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands // X shift by 0 -> X 1297c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands if (match(Op1, m_Zero())) 1298c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands return Op0; 1299c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 1300cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands // X shift by undef -> undef because it may shift by the bitwidth. 1301f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op1, m_Undef())) 1302c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands return Op1; 1303c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 1304c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands // Shifting by the bitwidth or more is undefined. 1305c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) 1306c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands if (CI->getValue().getLimitedValue() >= 1307c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands Op0->getType()->getScalarSizeInBits()) 1308c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands return UndefValue::get(Op0->getType()); 1309c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 1310cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands // If the operation is with the result of a select instruction, check whether 1311cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands // operating on either branch of the select always yields the same value. 1312cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands if (isa<SelectInst>(Op0) || isa<SelectInst>(Op1)) 13130aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverSelect(Opcode, Op0, Op1, Q, MaxRecurse)) 1314cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands return V; 1315cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands 1316cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands // If the operation is with the result of a phi instruction, check whether 1317cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands // operating on all incoming values of the phi always yields the same value. 1318cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands if (isa<PHINode>(Op0) || isa<PHINode>(Op1)) 13190aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverPHI(Opcode, Op0, Op1, Q, MaxRecurse)) 1320cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands return V; 1321cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands 1322cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands return 0; 1323cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands} 1324cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands 1325cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands/// SimplifyShlInst - Given operands for an Shl, see if we can 1326cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands/// fold the result. If not, this returns null. 132781a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattnerstatic Value *SimplifyShlInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW, 13280aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 13290aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyShift(Instruction::Shl, Op0, Op1, Q, MaxRecurse)) 1330cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands return V; 1331cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands 1332cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands // undef << X -> 0 1333f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op0, m_Undef())) 1334cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands return Constant::getNullValue(Op0->getType()); 1335cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands 133681a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner // (X >> A) << A -> X 133781a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner Value *X; 133855c6d57734cd2f141dc2d6912fc22746d5eeae54Benjamin Kramer if (match(Op0, m_Exact(m_Shr(m_Value(X), m_Specific(Op1))))) 133981a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner return X; 1340c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands return 0; 1341c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands} 1342c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 134381a0dc911586c77421c2255aa417dc9b350b9e20Chris LattnerValue *llvm::SimplifyShlInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW, 13443574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, const TargetLibraryInfo *TLI, 1345618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const DominatorTree *DT) { 13460aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyShlInst(Op0, Op1, isNSW, isNUW, Query (TD, TLI, DT), 13470aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RecursionLimit); 1348c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands} 1349c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 1350c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands/// SimplifyLShrInst - Given operands for an LShr, see if we can 1351c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands/// fold the result. If not, this returns null. 135281a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattnerstatic Value *SimplifyLShrInst(Value *Op0, Value *Op1, bool isExact, 13530aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 13540aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyShift(Instruction::LShr, Op0, Op1, Q, MaxRecurse)) 1355cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands return V; 1356c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 1357c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands // undef >>l X -> 0 1358f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op0, m_Undef())) 1359c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands return Constant::getNullValue(Op0->getType()); 1360c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 136181a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner // (X << A) >> A -> X 136281a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner Value *X; 136381a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner if (match(Op0, m_Shl(m_Value(X), m_Specific(Op1))) && 136481a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner cast<OverflowingBinaryOperator>(Op0)->hasNoUnsignedWrap()) 136581a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner return X; 136652fb846578714d14bbde9b28884a6a8729217677Duncan Sands 1367c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands return 0; 1368c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands} 1369c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 137081a0dc911586c77421c2255aa417dc9b350b9e20Chris LattnerValue *llvm::SimplifyLShrInst(Value *Op0, Value *Op1, bool isExact, 13713574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, 1372618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 1373618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const DominatorTree *DT) { 13740aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyLShrInst(Op0, Op1, isExact, Query (TD, TLI, DT), 13750aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RecursionLimit); 1376c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands} 1377c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 1378c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands/// SimplifyAShrInst - Given operands for an AShr, see if we can 1379c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands/// fold the result. If not, this returns null. 138081a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattnerstatic Value *SimplifyAShrInst(Value *Op0, Value *Op1, bool isExact, 13810aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 13820aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyShift(Instruction::AShr, Op0, Op1, Q, MaxRecurse)) 1383cf80bc1d4ac741620641c2bf48c25993bd478bd0Duncan Sands return V; 1384c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 1385c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands // all ones >>a X -> all ones 1386c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands if (match(Op0, m_AllOnes())) 1387c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands return Op0; 1388c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 1389c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands // undef >>a X -> all ones 1390f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op0, m_Undef())) 1391c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands return Constant::getAllOnesValue(Op0->getType()); 1392c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 139381a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner // (X << A) >> A -> X 139481a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner Value *X; 139581a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner if (match(Op0, m_Shl(m_Value(X), m_Specific(Op1))) && 139681a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner cast<OverflowingBinaryOperator>(Op0)->hasNoSignedWrap()) 139781a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner return X; 139852fb846578714d14bbde9b28884a6a8729217677Duncan Sands 1399c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands return 0; 1400c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands} 1401c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 140281a0dc911586c77421c2255aa417dc9b350b9e20Chris LattnerValue *llvm::SimplifyAShrInst(Value *Op0, Value *Op1, bool isExact, 14033574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, 1404618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 1405618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const DominatorTree *DT) { 14060aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyAShrInst(Op0, Op1, isExact, Query (TD, TLI, DT), 14070aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RecursionLimit); 1408c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands} 1409c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands 14108aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner/// SimplifyAndInst - Given operands for an And, see if we can 14118aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner/// fold the result. If not, this returns null. 14120aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyAndInst(Value *Op0, Value *Op1, const Query &Q, 1413618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier unsigned MaxRecurse) { 14148aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner if (Constant *CLHS = dyn_cast<Constant>(Op0)) { 14158aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner if (Constant *CRHS = dyn_cast<Constant>(Op1)) { 14168aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner Constant *Ops[] = { CLHS, CRHS }; 1417d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return ConstantFoldInstOperands(Instruction::And, CLHS->getType(), 14180aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Ops, Q.TD, Q.TLI); 1419d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner } 142012a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1421d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // Canonicalize the constant to the RHS. 1422d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner std::swap(Op0, Op1); 1423d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner } 142412a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1425d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // X & undef -> 0 1426f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op1, m_Undef())) 1427d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Constant::getNullValue(Op0->getType()); 142812a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1429d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // X & X = X 1430124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (Op0 == Op1) 1431d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Op0; 143212a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 14332b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands // X & 0 = 0 14342b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands if (match(Op1, m_Zero())) 1435d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Op1; 143612a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 14372b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands // X & -1 = X 14382b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands if (match(Op1, m_AllOnes())) 14392b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands return Op0; 144012a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1441d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // A & ~A = ~A & A = 0 144281a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner if (match(Op0, m_Not(m_Specific(Op1))) || 144381a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner match(Op1, m_Not(m_Specific(Op0)))) 1444d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Constant::getNullValue(Op0->getType()); 144512a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1446d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // (A | ?) & A = A 144781a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner Value *A = 0, *B = 0; 1448d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (match(Op0, m_Or(m_Value(A), m_Value(B))) && 1449124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands (A == Op1 || B == Op1)) 1450d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Op1; 145112a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1452d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // A & (A | ?) = A 1453d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (match(Op1, m_Or(m_Value(A), m_Value(B))) && 1454124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands (A == Op0 || B == Op0)) 1455d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Op0; 145612a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1457dd3149d57977d0632cfaf24290dd93416fb2a0efDuncan Sands // A & (-A) = A if A is a power of two or zero. 1458dd3149d57977d0632cfaf24290dd93416fb2a0efDuncan Sands if (match(Op0, m_Neg(m_Specific(Op1))) || 1459dd3149d57977d0632cfaf24290dd93416fb2a0efDuncan Sands match(Op1, m_Neg(m_Specific(Op0)))) { 1460dbaa2376f7b3c027e895ff4bee3ae08351f3ea88Rafael Espindola if (isKnownToBeAPowerOfTwo(Op0, /*OrZero*/true)) 1461dd3149d57977d0632cfaf24290dd93416fb2a0efDuncan Sands return Op0; 1462dbaa2376f7b3c027e895ff4bee3ae08351f3ea88Rafael Espindola if (isKnownToBeAPowerOfTwo(Op1, /*OrZero*/true)) 1463dd3149d57977d0632cfaf24290dd93416fb2a0efDuncan Sands return Op1; 1464dd3149d57977d0632cfaf24290dd93416fb2a0efDuncan Sands } 1465dd3149d57977d0632cfaf24290dd93416fb2a0efDuncan Sands 1466566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Try some generic simplifications for associative operations. 14670aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyAssociativeBinOp(Instruction::And, Op0, Op1, Q, 14680aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands MaxRecurse)) 1469566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return V; 14706844c8ea5a67e551be7106d6b7b9e1a64eecbe51Benjamin Kramer 14713421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // And distributes over Or. Try some generic simplifications based on this. 14723421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (Value *V = ExpandBinOp(Instruction::And, Op0, Op1, Instruction::Or, 14730aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse)) 14743421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return V; 14753421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 14763421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // And distributes over Xor. Try some generic simplifications based on this. 14773421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (Value *V = ExpandBinOp(Instruction::And, Op0, Op1, Instruction::Xor, 14780aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse)) 14793421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return V; 14803421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 14813421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Or distributes over And. Try some generic simplifications based on this. 14823421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (Value *V = FactorizeBinOp(Instruction::And, Op0, Op1, Instruction::Or, 14830aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse)) 14843421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return V; 14853421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 1486b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // If the operation is with the result of a select instruction, check whether 1487b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // operating on either branch of the select always yields the same value. 14880312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (isa<SelectInst>(Op0) || isa<SelectInst>(Op1)) 14890aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverSelect(Instruction::And, Op0, Op1, Q, 14900aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands MaxRecurse)) 1491a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands return V; 1492a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 1493a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // If the operation is with the result of a phi instruction, check whether 1494a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // operating on all incoming values of the phi always yields the same value. 14950312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (isa<PHINode>(Op0) || isa<PHINode>(Op1)) 14960aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverPHI(Instruction::And, Op0, Op1, Q, 14970312a93693abc2eb682b2b101c889959888fd883Duncan Sands MaxRecurse)) 1498b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands return V; 1499b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 1500d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return 0; 1501d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner} 15029f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner 15033574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifyAndInst(Value *Op0, Value *Op1, const DataLayout *TD, 1504618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 15051845009290e4d804ad377927bd8a08cca3036adcDuncan Sands const DominatorTree *DT) { 15060aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyAndInst(Op0, Op1, Query (TD, TLI, DT), RecursionLimit); 1507a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands} 1508a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 1509d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner/// SimplifyOrInst - Given operands for an Or, see if we can 15109f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner/// fold the result. If not, this returns null. 15110aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyOrInst(Value *Op0, Value *Op1, const Query &Q, 15120aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands unsigned MaxRecurse) { 1513d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (Constant *CLHS = dyn_cast<Constant>(Op0)) { 1514d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (Constant *CRHS = dyn_cast<Constant>(Op1)) { 1515d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner Constant *Ops[] = { CLHS, CRHS }; 1516d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return ConstantFoldInstOperands(Instruction::Or, CLHS->getType(), 15170aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Ops, Q.TD, Q.TLI); 1518d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner } 151912a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1520d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // Canonicalize the constant to the RHS. 1521d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner std::swap(Op0, Op1); 1522d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner } 152312a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1524d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // X | undef -> -1 1525f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op1, m_Undef())) 1526d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Constant::getAllOnesValue(Op0->getType()); 152712a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1528d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // X | X = X 1529124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (Op0 == Op1) 1530d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Op0; 1531d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner 15322b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands // X | 0 = X 15332b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands if (match(Op1, m_Zero())) 1534d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Op0; 153512a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 15362b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands // X | -1 = -1 15372b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands if (match(Op1, m_AllOnes())) 15382b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands return Op1; 153912a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1540d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // A | ~A = ~A | A = -1 154181a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner if (match(Op0, m_Not(m_Specific(Op1))) || 154281a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner match(Op1, m_Not(m_Specific(Op0)))) 1543d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Constant::getAllOnesValue(Op0->getType()); 154412a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1545d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // (A & ?) | A = A 154681a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner Value *A = 0, *B = 0; 1547d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (match(Op0, m_And(m_Value(A), m_Value(B))) && 1548124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands (A == Op1 || B == Op1)) 1549d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Op1; 155012a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1551d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // A | (A & ?) = A 1552d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (match(Op1, m_And(m_Value(A), m_Value(B))) && 1553124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands (A == Op0 || B == Op0)) 1554d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return Op0; 155512a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 155638f7f66fcc6ed5e43be4d9c96c782d4eabdb7342Benjamin Kramer // ~(A & ?) | A = -1 155738f7f66fcc6ed5e43be4d9c96c782d4eabdb7342Benjamin Kramer if (match(Op0, m_Not(m_And(m_Value(A), m_Value(B)))) && 155838f7f66fcc6ed5e43be4d9c96c782d4eabdb7342Benjamin Kramer (A == Op1 || B == Op1)) 155938f7f66fcc6ed5e43be4d9c96c782d4eabdb7342Benjamin Kramer return Constant::getAllOnesValue(Op1->getType()); 156038f7f66fcc6ed5e43be4d9c96c782d4eabdb7342Benjamin Kramer 156138f7f66fcc6ed5e43be4d9c96c782d4eabdb7342Benjamin Kramer // A | ~(A & ?) = -1 156238f7f66fcc6ed5e43be4d9c96c782d4eabdb7342Benjamin Kramer if (match(Op1, m_Not(m_And(m_Value(A), m_Value(B)))) && 156338f7f66fcc6ed5e43be4d9c96c782d4eabdb7342Benjamin Kramer (A == Op0 || B == Op0)) 156438f7f66fcc6ed5e43be4d9c96c782d4eabdb7342Benjamin Kramer return Constant::getAllOnesValue(Op0->getType()); 156538f7f66fcc6ed5e43be4d9c96c782d4eabdb7342Benjamin Kramer 1566566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Try some generic simplifications for associative operations. 15670aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyAssociativeBinOp(Instruction::Or, Op0, Op1, Q, 15680aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands MaxRecurse)) 1569566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return V; 15706844c8ea5a67e551be7106d6b7b9e1a64eecbe51Benjamin Kramer 15713421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // Or distributes over And. Try some generic simplifications based on this. 15720aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ExpandBinOp(Instruction::Or, Op0, Op1, Instruction::And, Q, 15730aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands MaxRecurse)) 15743421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return V; 15753421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 15763421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // And distributes over Or. Try some generic simplifications based on this. 15773421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (Value *V = FactorizeBinOp(Instruction::Or, Op0, Op1, Instruction::And, 15780aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse)) 15793421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return V; 15803421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 1581b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // If the operation is with the result of a select instruction, check whether 1582b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // operating on either branch of the select always yields the same value. 15830312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (isa<SelectInst>(Op0) || isa<SelectInst>(Op1)) 15840aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverSelect(Instruction::Or, Op0, Op1, Q, 15850312a93693abc2eb682b2b101c889959888fd883Duncan Sands MaxRecurse)) 1586a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands return V; 1587a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 1588a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // If the operation is with the result of a phi instruction, check whether 1589a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // operating on all incoming values of the phi always yields the same value. 15900312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (isa<PHINode>(Op0) || isa<PHINode>(Op1)) 15910aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverPHI(Instruction::Or, Op0, Op1, Q, MaxRecurse)) 1592b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands return V; 1593b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 15949f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner return 0; 15959f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner} 15969f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner 15973574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifyOrInst(Value *Op0, Value *Op1, const DataLayout *TD, 1598618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 15991845009290e4d804ad377927bd8a08cca3036adcDuncan Sands const DominatorTree *DT) { 16000aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyOrInst(Op0, Op1, Query (TD, TLI, DT), RecursionLimit); 1601a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands} 1602d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner 16032b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands/// SimplifyXorInst - Given operands for a Xor, see if we can 16042b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands/// fold the result. If not, this returns null. 16050aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyXorInst(Value *Op0, Value *Op1, const Query &Q, 16060aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands unsigned MaxRecurse) { 16072b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands if (Constant *CLHS = dyn_cast<Constant>(Op0)) { 16082b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands if (Constant *CRHS = dyn_cast<Constant>(Op1)) { 16092b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands Constant *Ops[] = { CLHS, CRHS }; 16102b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands return ConstantFoldInstOperands(Instruction::Xor, CLHS->getType(), 16110aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Ops, Q.TD, Q.TLI); 16122b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands } 16132b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands 16142b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands // Canonicalize the constant to the RHS. 16152b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands std::swap(Op0, Op1); 16162b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands } 16172b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands 16182b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands // A ^ undef -> undef 1619f9e4a986c03fe3af7dbc9de0b0a9251280fbdf41Duncan Sands if (match(Op1, m_Undef())) 1620f8b1a5ea9602bb65a5cf59d3d34f2851a08cdc3eDuncan Sands return Op1; 16212b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands 16222b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands // A ^ 0 = A 16232b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands if (match(Op1, m_Zero())) 16242b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands return Op0; 16252b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands 1626f23d4adbfaf870d5fa67c6bff0da7891d3a98f9dEli Friedman // A ^ A = 0 1627f23d4adbfaf870d5fa67c6bff0da7891d3a98f9dEli Friedman if (Op0 == Op1) 1628f23d4adbfaf870d5fa67c6bff0da7891d3a98f9dEli Friedman return Constant::getNullValue(Op0->getType()); 1629f23d4adbfaf870d5fa67c6bff0da7891d3a98f9dEli Friedman 16302b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands // A ^ ~A = ~A ^ A = -1 163181a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner if (match(Op0, m_Not(m_Specific(Op1))) || 163281a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner match(Op1, m_Not(m_Specific(Op0)))) 16332b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands return Constant::getAllOnesValue(Op0->getType()); 16342b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands 1635566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // Try some generic simplifications for associative operations. 16360aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyAssociativeBinOp(Instruction::Xor, Op0, Op1, Q, 16370aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands MaxRecurse)) 1638566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return V; 16392b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands 16403421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands // And distributes over Xor. Try some generic simplifications based on this. 16413421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands if (Value *V = FactorizeBinOp(Instruction::Xor, Op0, Op1, Instruction::And, 16420aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse)) 16433421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands return V; 16443421d908539cc489d2b1dac67d8cbc07160b01dbDuncan Sands 164587689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // Threading Xor over selects and phi nodes is pointless, so don't bother. 164687689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // Threading over the select in "A ^ select(cond, B, C)" means evaluating 164787689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // "A^B" and "A^C" and seeing if they are equal; but they are equal if and 164887689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // only if B and C are equal. If B and C are equal then (since we assume 164987689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // that operands have already been simplified) "select(cond, B, C)" should 165087689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // have been simplified to the common value of B and C already. Analysing 165187689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // "A^B" and "A^C" thus gains nothing, but costs compile time. Similarly 165287689cfc54993959adb20b89a56bc58aad18ca56Duncan Sands // for threading over phi nodes. 16532b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands 16542b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands return 0; 16552b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands} 16562b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands 16573574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifyXorInst(Value *Op0, Value *Op1, const DataLayout *TD, 1658618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 16592b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands const DominatorTree *DT) { 16600aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyXorInst(Op0, Op1, Query (TD, TLI, DT), RecursionLimit); 16612b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands} 16622b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands 1663db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattnerstatic Type *GetCompareTy(Value *Op) { 1664210c5d4880b525e064088b6fec713260128c16ebChris Lattner return CmpInst::makeCmpResultType(Op->getType()); 1665210c5d4880b525e064088b6fec713260128c16ebChris Lattner} 1666210c5d4880b525e064088b6fec713260128c16ebChris Lattner 1667e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands/// ExtractEquivalentCondition - Rummage around inside V looking for something 1668e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands/// equivalent to the comparison "LHS Pred RHS". Return such a value if found, 1669e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands/// otherwise return null. Helper function for analyzing max/min idioms. 1670e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sandsstatic Value *ExtractEquivalentCondition(Value *V, CmpInst::Predicate Pred, 1671e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands Value *LHS, Value *RHS) { 1672e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands SelectInst *SI = dyn_cast<SelectInst>(V); 1673e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (!SI) 1674e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return 0; 1675e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands CmpInst *Cmp = dyn_cast<CmpInst>(SI->getCondition()); 1676e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (!Cmp) 1677e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return 0; 1678e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands Value *CmpLHS = Cmp->getOperand(0), *CmpRHS = Cmp->getOperand(1); 1679e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (Pred == Cmp->getPredicate() && LHS == CmpLHS && RHS == CmpRHS) 1680e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return Cmp; 1681e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (Pred == CmpInst::getSwappedPredicate(Cmp->getPredicate()) && 1682e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands LHS == CmpRHS && RHS == CmpLHS) 1683e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return Cmp; 1684e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return 0; 1685e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands} 1686e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands 16873574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmowstatic Constant *computePointerICmp(const DataLayout &TD, 168858725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth CmpInst::Predicate Pred, 168958725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth Value *LHS, Value *RHS) { 169058725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth // We can only fold certain predicates on pointer comparisons. 169158725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth switch (Pred) { 169258725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth default: 169358725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth return 0; 169458725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth 169558725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth // Equality comaprisons are easy to fold. 169658725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth case CmpInst::ICMP_EQ: 169758725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth case CmpInst::ICMP_NE: 169858725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth break; 169958725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth 170058725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth // We can only handle unsigned relational comparisons because 'inbounds' on 170158725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth // a GEP only protects against unsigned wrapping. 170258725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth case CmpInst::ICMP_UGT: 170358725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth case CmpInst::ICMP_UGE: 170458725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth case CmpInst::ICMP_ULT: 170558725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth case CmpInst::ICMP_ULE: 170658725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth // However, we have to switch them to their signed variants to handle 170758725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth // negative indices from the base pointer. 170858725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth Pred = ICmpInst::getSignedPredicate(Pred); 170958725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth break; 171058725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth } 171158725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth 171258725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth Constant *LHSOffset = stripAndComputeConstantOffsets(TD, LHS); 171358725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth if (!LHSOffset) 171458725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth return 0; 171558725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth Constant *RHSOffset = stripAndComputeConstantOffsets(TD, RHS); 171658725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth if (!RHSOffset) 171758725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth return 0; 171858725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth 171958725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth // If LHS and RHS are not related via constant offsets to the same base 172058725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth // value, there is nothing we can do here. 172158725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth if (LHS != RHS) 172258725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth return 0; 172358725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth 172458725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth return ConstantExpr::getICmp(Pred, LHSOffset, RHSOffset); 172558725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth} 1726009e2650d69fe93bda1864340c5f000e56c52fb8Chris Lattner 17279dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner/// SimplifyICmpInst - Given operands for an ICmpInst, see if we can 17289dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner/// fold the result. If not, this returns null. 1729a74a58c83be492b7d5b7383656f049909394cff4Duncan Sandsstatic Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, 17300aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 17319f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner CmpInst::Predicate Pred = (CmpInst::Predicate)Predicate; 17329dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner assert(CmpInst::isIntPredicate(Pred) && "Not an integer compare!"); 173312a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1734d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (Constant *CLHS = dyn_cast<Constant>(LHS)) { 17358f73deaa8732a556046bf4ac6207be55972e3b74Chris Lattner if (Constant *CRHS = dyn_cast<Constant>(RHS)) 17360aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ConstantFoldCompareInstOperands(Pred, CLHS, CRHS, Q.TD, Q.TLI); 1737d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner 1738d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // If we have a constant, make sure it is on the RHS. 1739d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner std::swap(LHS, RHS); 1740d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner Pred = CmpInst::getSwappedPredicate(Pred); 1741d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner } 174212a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1743db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *ITy = GetCompareTy(LHS); // The return type. 1744db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *OpTy = LHS->getType(); // The operand type. 174512a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1746210c5d4880b525e064088b6fec713260128c16ebChris Lattner // icmp X, X -> true/false 1747c8e14b3d37b80abb6adb4b831af0452d9ecbf2b2Chris Lattner // X icmp undef -> true/false. For example, icmp ugt %X, undef -> false 1748c8e14b3d37b80abb6adb4b831af0452d9ecbf2b2Chris Lattner // because X could be 0. 1749124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (LHS == RHS || isa<UndefValue>(RHS)) 1750210c5d4880b525e064088b6fec713260128c16ebChris Lattner return ConstantInt::get(ITy, CmpInst::isTrueWhenEqual(Pred)); 175112a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 17526dc91253ab1872e118b08511a09d5c934988354eDuncan Sands // Special case logic when the operands have i1 type. 175366d004ef708642bbdc38fd761507f2e9ee3970cdNick Lewycky if (OpTy->getScalarType()->isIntegerTy(1)) { 17546dc91253ab1872e118b08511a09d5c934988354eDuncan Sands switch (Pred) { 17556dc91253ab1872e118b08511a09d5c934988354eDuncan Sands default: break; 17566dc91253ab1872e118b08511a09d5c934988354eDuncan Sands case ICmpInst::ICMP_EQ: 17576dc91253ab1872e118b08511a09d5c934988354eDuncan Sands // X == 1 -> X 17586dc91253ab1872e118b08511a09d5c934988354eDuncan Sands if (match(RHS, m_One())) 17596dc91253ab1872e118b08511a09d5c934988354eDuncan Sands return LHS; 17606dc91253ab1872e118b08511a09d5c934988354eDuncan Sands break; 17616dc91253ab1872e118b08511a09d5c934988354eDuncan Sands case ICmpInst::ICMP_NE: 17626dc91253ab1872e118b08511a09d5c934988354eDuncan Sands // X != 0 -> X 17636dc91253ab1872e118b08511a09d5c934988354eDuncan Sands if (match(RHS, m_Zero())) 17646dc91253ab1872e118b08511a09d5c934988354eDuncan Sands return LHS; 17656dc91253ab1872e118b08511a09d5c934988354eDuncan Sands break; 17666dc91253ab1872e118b08511a09d5c934988354eDuncan Sands case ICmpInst::ICMP_UGT: 17676dc91253ab1872e118b08511a09d5c934988354eDuncan Sands // X >u 0 -> X 17686dc91253ab1872e118b08511a09d5c934988354eDuncan Sands if (match(RHS, m_Zero())) 17696dc91253ab1872e118b08511a09d5c934988354eDuncan Sands return LHS; 17706dc91253ab1872e118b08511a09d5c934988354eDuncan Sands break; 17716dc91253ab1872e118b08511a09d5c934988354eDuncan Sands case ICmpInst::ICMP_UGE: 17726dc91253ab1872e118b08511a09d5c934988354eDuncan Sands // X >=u 1 -> X 17736dc91253ab1872e118b08511a09d5c934988354eDuncan Sands if (match(RHS, m_One())) 17746dc91253ab1872e118b08511a09d5c934988354eDuncan Sands return LHS; 17756dc91253ab1872e118b08511a09d5c934988354eDuncan Sands break; 17766dc91253ab1872e118b08511a09d5c934988354eDuncan Sands case ICmpInst::ICMP_SLT: 17776dc91253ab1872e118b08511a09d5c934988354eDuncan Sands // X <s 0 -> X 17786dc91253ab1872e118b08511a09d5c934988354eDuncan Sands if (match(RHS, m_Zero())) 17796dc91253ab1872e118b08511a09d5c934988354eDuncan Sands return LHS; 17806dc91253ab1872e118b08511a09d5c934988354eDuncan Sands break; 17816dc91253ab1872e118b08511a09d5c934988354eDuncan Sands case ICmpInst::ICMP_SLE: 17826dc91253ab1872e118b08511a09d5c934988354eDuncan Sands // X <=s -1 -> X 17836dc91253ab1872e118b08511a09d5c934988354eDuncan Sands if (match(RHS, m_One())) 17846dc91253ab1872e118b08511a09d5c934988354eDuncan Sands return LHS; 17856dc91253ab1872e118b08511a09d5c934988354eDuncan Sands break; 17866dc91253ab1872e118b08511a09d5c934988354eDuncan Sands } 17876dc91253ab1872e118b08511a09d5c934988354eDuncan Sands } 178812a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 1789f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // icmp <object*>, <object*/null> - Different identified objects have 1790f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // different addresses (unless null), and what's more the address of an 1791f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // identified local is never equal to another argument (again, barring null). 1792f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // Note that generalizing to the case where LHS is a global variable address 1793f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // or null is pointless, since if both LHS and RHS are constants then we 1794f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // already constant folded the compare, and if only one of them is then we 1795f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // moved it to RHS already. 1796ea79b8e03ca7c7be72832c11e9d4d78f11b728b3Benjamin Kramer Value *LHSPtr = LHS->stripPointerCasts(); 1797ea79b8e03ca7c7be72832c11e9d4d78f11b728b3Benjamin Kramer Value *RHSPtr = RHS->stripPointerCasts(); 17982c3acb0e273a50a9b4eeaf9d5544f6168bda85a6Eli Friedman if (LHSPtr == RHSPtr) 17992c3acb0e273a50a9b4eeaf9d5544f6168bda85a6Eli Friedman return ConstantInt::get(ITy, CmpInst::isTrueWhenEqual(Pred)); 1800f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky 1801b053fc1c92b6b81c47d5e2c092b0f3ea04fd5b87Chris Lattner // Be more aggressive about stripping pointer adjustments when checking a 1802b053fc1c92b6b81c47d5e2c092b0f3ea04fd5b87Chris Lattner // comparison of an alloca address to another object. We can rip off all 1803b053fc1c92b6b81c47d5e2c092b0f3ea04fd5b87Chris Lattner // inbounds GEP operations, even if they are variable. 180484dfc32ff906271c373819595e60a173624e1184Chandler Carruth LHSPtr = LHSPtr->stripInBoundsOffsets(); 1805f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky if (llvm::isIdentifiedObject(LHSPtr)) { 180684dfc32ff906271c373819595e60a173624e1184Chandler Carruth RHSPtr = RHSPtr->stripInBoundsOffsets(); 1807f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky if (llvm::isKnownNonNull(LHSPtr) || llvm::isKnownNonNull(RHSPtr)) { 1808f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // If both sides are different identified objects, they aren't equal 1809f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // unless they're null. 1810c17731d65d2c059a71256ee995cbb057ff28a109Bill Wendling if (LHSPtr != RHSPtr && llvm::isIdentifiedObject(RHSPtr) && 1811798d013bcba198af628d2dab8448f709b96e4a75Bill Wendling Pred == CmpInst::ICMP_EQ) 1812c17731d65d2c059a71256ee995cbb057ff28a109Bill Wendling return ConstantInt::get(ITy, false); 1813f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky 1814f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // A local identified object (alloca or noalias call) can't equal any 1815961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth // incoming argument, unless they're both null or they belong to 1816961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth // different functions. The latter happens during inlining. 1817961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth if (Instruction *LHSInst = dyn_cast<Instruction>(LHSPtr)) 1818961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth if (Argument *RHSArg = dyn_cast<Argument>(RHSPtr)) 1819961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth if (LHSInst->getParent()->getParent() == RHSArg->getParent() && 1820961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth Pred == CmpInst::ICMP_EQ) 1821961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth return ConstantInt::get(ITy, false); 1822f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky } 1823f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky 1824f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // Assume that the constant null is on the right. 1825c17731d65d2c059a71256ee995cbb057ff28a109Bill Wendling if (llvm::isKnownNonNull(LHSPtr) && isa<ConstantPointerNull>(RHSPtr)) { 1826798d013bcba198af628d2dab8448f709b96e4a75Bill Wendling if (Pred == CmpInst::ICMP_EQ) 1827c17731d65d2c059a71256ee995cbb057ff28a109Bill Wendling return ConstantInt::get(ITy, false); 1828798d013bcba198af628d2dab8448f709b96e4a75Bill Wendling else if (Pred == CmpInst::ICMP_NE) 1829c17731d65d2c059a71256ee995cbb057ff28a109Bill Wendling return ConstantInt::get(ITy, true); 1830c17731d65d2c059a71256ee995cbb057ff28a109Bill Wendling } 1831961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth } else if (Argument *LHSArg = dyn_cast<Argument>(LHSPtr)) { 183284dfc32ff906271c373819595e60a173624e1184Chandler Carruth RHSPtr = RHSPtr->stripInBoundsOffsets(); 1833961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth // An alloca can't be equal to an argument unless they come from separate 1834961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth // functions via inlining. 1835961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth if (AllocaInst *RHSInst = dyn_cast<AllocaInst>(RHSPtr)) { 1836961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth if (LHSArg->getParent() == RHSInst->getParent()->getParent()) { 1837961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth if (Pred == CmpInst::ICMP_EQ) 1838961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth return ConstantInt::get(ITy, false); 1839961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth else if (Pred == CmpInst::ICMP_NE) 1840961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth return ConstantInt::get(ITy, true); 1841961e1acfb275613679c0d00d4a0b4ed394b51a9dChandler Carruth } 1842c17731d65d2c059a71256ee995cbb057ff28a109Bill Wendling } 1843b053fc1c92b6b81c47d5e2c092b0f3ea04fd5b87Chris Lattner } 1844d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands 1845d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands // If we are comparing with zero then try hard since this is a common case. 1846d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands if (match(RHS, m_Zero())) { 1847d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands bool LHSKnownNonNegative, LHSKnownNegative; 1848d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands switch (Pred) { 1849858143816d43e58b17bfd11cb1b57afbd7f0f893Craig Topper default: llvm_unreachable("Unknown ICmp predicate!"); 1850d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands case ICmpInst::ICMP_ULT: 1851f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 1852d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands case ICmpInst::ICMP_UGE: 1853f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 1854d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands case ICmpInst::ICMP_EQ: 1855d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands case ICmpInst::ICMP_ULE: 18560aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (isKnownNonZero(LHS, Q.TD)) 1857f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 1858d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands break; 1859d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands case ICmpInst::ICMP_NE: 1860d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands case ICmpInst::ICMP_UGT: 18610aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (isKnownNonZero(LHS, Q.TD)) 1862f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 1863d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands break; 1864d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands case ICmpInst::ICMP_SLT: 18650aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands ComputeSignBit(LHS, LHSKnownNonNegative, LHSKnownNegative, Q.TD); 1866d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands if (LHSKnownNegative) 1867f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 1868d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands if (LHSKnownNonNegative) 1869f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 1870d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands break; 1871d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands case ICmpInst::ICMP_SLE: 18720aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands ComputeSignBit(LHS, LHSKnownNonNegative, LHSKnownNegative, Q.TD); 1873d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands if (LHSKnownNegative) 1874f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 18750aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (LHSKnownNonNegative && isKnownNonZero(LHS, Q.TD)) 1876f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 1877d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands break; 1878d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands case ICmpInst::ICMP_SGE: 18790aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands ComputeSignBit(LHS, LHSKnownNonNegative, LHSKnownNegative, Q.TD); 1880d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands if (LHSKnownNegative) 1881f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 1882d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands if (LHSKnownNonNegative) 1883f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 1884d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands break; 1885d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands case ICmpInst::ICMP_SGT: 18860aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands ComputeSignBit(LHS, LHSKnownNonNegative, LHSKnownNegative, Q.TD); 1887d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands if (LHSKnownNegative) 1888f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 18890aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (LHSKnownNonNegative && isKnownNonZero(LHS, Q.TD)) 1890f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 1891d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands break; 1892d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands } 1893d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands } 1894d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands 1895d70d1a5c44609af091f6fc3e29193f9f4756a74fDuncan Sands // See if we are doing a comparison with a constant integer. 1896210c5d4880b525e064088b6fec713260128c16ebChris Lattner if (ConstantInt *CI = dyn_cast<ConstantInt>(RHS)) { 18973a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky // Rule out tautological comparisons (eg., ult 0 or uge 0). 18983a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky ConstantRange RHS_CR = ICmpInst::makeConstantRange(Pred, CI->getValue()); 18993a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky if (RHS_CR.isEmptySet()) 19003a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky return ConstantInt::getFalse(CI->getContext()); 19013a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky if (RHS_CR.isFullSet()) 19023a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky return ConstantInt::getTrue(CI->getContext()); 19033a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky 19043a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky // Many binary operators with constant RHS have easy to compute constant 19053a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky // range. Use them to check whether the comparison is a tautology. 19063a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky uint32_t Width = CI->getBitWidth(); 19073a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky APInt Lower = APInt(Width, 0); 19083a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky APInt Upper = APInt(Width, 0); 19093a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky ConstantInt *CI2; 19103a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky if (match(LHS, m_URem(m_Value(), m_ConstantInt(CI2)))) { 19113a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky // 'urem x, CI2' produces [0, CI2). 19123a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky Upper = CI2->getValue(); 19133a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky } else if (match(LHS, m_SRem(m_Value(), m_ConstantInt(CI2)))) { 19143a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky // 'srem x, CI2' produces (-|CI2|, |CI2|). 19153a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky Upper = CI2->getValue().abs(); 19163a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky Lower = (-Upper) + 1; 1917c65c747bc4ee7d3ca8463d33708bbb2aed38a809Duncan Sands } else if (match(LHS, m_UDiv(m_ConstantInt(CI2), m_Value()))) { 1918c65c747bc4ee7d3ca8463d33708bbb2aed38a809Duncan Sands // 'udiv CI2, x' produces [0, CI2]. 19197781ae5be570940178295f6f808215089a3fe411Eli Friedman Upper = CI2->getValue() + 1; 19203a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky } else if (match(LHS, m_UDiv(m_Value(), m_ConstantInt(CI2)))) { 19213a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky // 'udiv x, CI2' produces [0, UINT_MAX / CI2]. 19223a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky APInt NegOne = APInt::getAllOnesValue(Width); 19233a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky if (!CI2->isZero()) 19243a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky Upper = NegOne.udiv(CI2->getValue()) + 1; 19253a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky } else if (match(LHS, m_SDiv(m_Value(), m_ConstantInt(CI2)))) { 19263a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky // 'sdiv x, CI2' produces [INT_MIN / CI2, INT_MAX / CI2]. 19273a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky APInt IntMin = APInt::getSignedMinValue(Width); 19283a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky APInt IntMax = APInt::getSignedMaxValue(Width); 19293a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky APInt Val = CI2->getValue().abs(); 19303a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky if (!Val.isMinValue()) { 19313a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky Lower = IntMin.sdiv(Val); 19323a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky Upper = IntMax.sdiv(Val) + 1; 19333a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky } 19343a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky } else if (match(LHS, m_LShr(m_Value(), m_ConstantInt(CI2)))) { 19353a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky // 'lshr x, CI2' produces [0, UINT_MAX >> CI2]. 19363a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky APInt NegOne = APInt::getAllOnesValue(Width); 19373a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky if (CI2->getValue().ult(Width)) 19383a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky Upper = NegOne.lshr(CI2->getValue()) + 1; 19393a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky } else if (match(LHS, m_AShr(m_Value(), m_ConstantInt(CI2)))) { 19403a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky // 'ashr x, CI2' produces [INT_MIN >> CI2, INT_MAX >> CI2]. 19413a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky APInt IntMin = APInt::getSignedMinValue(Width); 19423a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky APInt IntMax = APInt::getSignedMaxValue(Width); 19433a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky if (CI2->getValue().ult(Width)) { 19443a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky Lower = IntMin.ashr(CI2->getValue()); 19453a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky Upper = IntMax.ashr(CI2->getValue()) + 1; 19463a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky } 19473a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky } else if (match(LHS, m_Or(m_Value(), m_ConstantInt(CI2)))) { 19483a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky // 'or x, CI2' produces [CI2, UINT_MAX]. 19493a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky Lower = CI2->getValue(); 19503a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky } else if (match(LHS, m_And(m_Value(), m_ConstantInt(CI2)))) { 19513a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky // 'and x, CI2' produces [0, CI2]. 19523a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky Upper = CI2->getValue() + 1; 19533a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky } 19543a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky if (Lower != Upper) { 19553a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky ConstantRange LHS_CR = ConstantRange(Lower, Upper); 19563a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky if (RHS_CR.contains(LHS_CR)) 19573a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky return ConstantInt::getTrue(RHS->getContext()); 19583a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky if (RHS_CR.inverse().contains(LHS_CR)) 19593a73e343d02ba3a00adf03311183cc0ccc960978Nick Lewycky return ConstantInt::getFalse(RHS->getContext()); 1960210c5d4880b525e064088b6fec713260128c16ebChris Lattner } 1961210c5d4880b525e064088b6fec713260128c16ebChris Lattner } 19621ac7c9979a2d723ff4649ffad58df02732872a5fDuncan Sands 19639d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Compare of cast, for example (zext X) != 0 -> X != 0 19649d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (isa<CastInst>(LHS) && (isa<Constant>(RHS) || isa<CastInst>(RHS))) { 19659d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands Instruction *LI = cast<CastInst>(LHS); 19669d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands Value *SrcOp = LI->getOperand(0); 1967db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *SrcTy = SrcOp->getType(); 1968db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *DstTy = LI->getType(); 19699d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 19709d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Turn icmp (ptrtoint x), (ptrtoint/constant) into a compare of the input 19719d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // if the integer type is the same size as the pointer type. 19720aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (MaxRecurse && Q.TD && isa<PtrToIntInst>(LI) && 1973426c2bf5cdd2173e4a33aea8cb92cf684a724f4bChandler Carruth Q.TD->getPointerSizeInBits() == DstTy->getPrimitiveSizeInBits()) { 19749d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (Constant *RHSC = dyn_cast<Constant>(RHS)) { 19759d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Transfer the cast to the constant. 19769d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (Value *V = SimplifyICmpInst(Pred, SrcOp, 19779d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands ConstantExpr::getIntToPtr(RHSC, SrcTy), 19780aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse-1)) 19799d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return V; 19809d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } else if (PtrToIntInst *RI = dyn_cast<PtrToIntInst>(RHS)) { 19819d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (RI->getOperand(0)->getType() == SrcTy) 19829d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Compare without the cast. 19839d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (Value *V = SimplifyICmpInst(Pred, SrcOp, RI->getOperand(0), 19840aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse-1)) 19859d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return V; 19869d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 19879d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 19889d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 19899d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (isa<ZExtInst>(LHS)) { 19909d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Turn icmp (zext X), (zext Y) into a compare of X and Y if they have the 19919d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // same type. 19929d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (ZExtInst *RI = dyn_cast<ZExtInst>(RHS)) { 19939d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (MaxRecurse && SrcTy == RI->getOperand(0)->getType()) 19949d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Compare X and Y. Note that signed predicates become unsigned. 19959d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (Value *V = SimplifyICmpInst(ICmpInst::getUnsignedPredicate(Pred), 19960aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands SrcOp, RI->getOperand(0), Q, 19979d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands MaxRecurse-1)) 19989d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return V; 19999d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 20009d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Turn icmp (zext X), Cst into a compare of X and Cst if Cst is extended 20019d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // too. If not, then try to deduce the result of the comparison. 20029d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands else if (ConstantInt *CI = dyn_cast<ConstantInt>(RHS)) { 20039d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Compute the constant that would happen if we truncated to SrcTy then 20049d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // reextended to DstTy. 20059d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands Constant *Trunc = ConstantExpr::getTrunc(CI, SrcTy); 20069d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands Constant *RExt = ConstantExpr::getCast(CastInst::ZExt, Trunc, DstTy); 20079d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 20089d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // If the re-extended constant didn't change then this is effectively 20099d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // also a case of comparing two zero-extended values. 20109d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (RExt == CI && MaxRecurse) 20119d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (Value *V = SimplifyICmpInst(ICmpInst::getUnsignedPredicate(Pred), 20120aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands SrcOp, Trunc, Q, MaxRecurse-1)) 20139d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return V; 20149d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 20159d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Otherwise the upper bits of LHS are zero while RHS has a non-zero bit 20169d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // there. Use this to work out the result of the comparison. 20179d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (RExt != CI) { 20189d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands switch (Pred) { 2019858143816d43e58b17bfd11cb1b57afbd7f0f893Craig Topper default: llvm_unreachable("Unknown ICmp predicate!"); 20209d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // LHS <u RHS. 20219d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_EQ: 20229d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_UGT: 20239d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_UGE: 20249d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return ConstantInt::getFalse(CI->getContext()); 20259d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 20269d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_NE: 20279d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_ULT: 20289d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_ULE: 20299d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return ConstantInt::getTrue(CI->getContext()); 20309d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 20319d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // LHS is non-negative. If RHS is negative then LHS >s LHS. If RHS 20329d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // is non-negative then LHS <s RHS. 20339d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_SGT: 20349d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_SGE: 20359d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return CI->getValue().isNegative() ? 20369d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands ConstantInt::getTrue(CI->getContext()) : 20379d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands ConstantInt::getFalse(CI->getContext()); 20389d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 20399d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_SLT: 20409d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_SLE: 20419d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return CI->getValue().isNegative() ? 20429d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands ConstantInt::getFalse(CI->getContext()) : 20439d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands ConstantInt::getTrue(CI->getContext()); 20449d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 20459d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 20469d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 20479d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 20489d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 20499d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (isa<SExtInst>(LHS)) { 20509d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Turn icmp (sext X), (sext Y) into a compare of X and Y if they have the 20519d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // same type. 20529d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (SExtInst *RI = dyn_cast<SExtInst>(RHS)) { 20539d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (MaxRecurse && SrcTy == RI->getOperand(0)->getType()) 20549d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Compare X and Y. Note that the predicate does not change. 20559d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (Value *V = SimplifyICmpInst(Pred, SrcOp, RI->getOperand(0), 20560aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse-1)) 20579d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return V; 20589d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 20599d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Turn icmp (sext X), Cst into a compare of X and Cst if Cst is extended 20609d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // too. If not, then try to deduce the result of the comparison. 20619d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands else if (ConstantInt *CI = dyn_cast<ConstantInt>(RHS)) { 20629d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Compute the constant that would happen if we truncated to SrcTy then 20639d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // reextended to DstTy. 20649d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands Constant *Trunc = ConstantExpr::getTrunc(CI, SrcTy); 20659d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands Constant *RExt = ConstantExpr::getCast(CastInst::SExt, Trunc, DstTy); 20669d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 20679d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // If the re-extended constant didn't change then this is effectively 20689d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // also a case of comparing two sign-extended values. 20699d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (RExt == CI && MaxRecurse) 20700aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyICmpInst(Pred, SrcOp, Trunc, Q, MaxRecurse-1)) 20719d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return V; 20729d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 20739d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // Otherwise the upper bits of LHS are all equal, while RHS has varying 20749d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // bits there. Use this to work out the result of the comparison. 20759d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (RExt != CI) { 20769d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands switch (Pred) { 2077858143816d43e58b17bfd11cb1b57afbd7f0f893Craig Topper default: llvm_unreachable("Unknown ICmp predicate!"); 20789d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_EQ: 20799d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return ConstantInt::getFalse(CI->getContext()); 20809d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_NE: 20819d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return ConstantInt::getTrue(CI->getContext()); 20829d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 20839d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // If RHS is non-negative then LHS <s RHS. If RHS is negative then 20849d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // LHS >s RHS. 20859d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_SGT: 20869d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_SGE: 20879d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return CI->getValue().isNegative() ? 20889d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands ConstantInt::getTrue(CI->getContext()) : 20899d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands ConstantInt::getFalse(CI->getContext()); 20909d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_SLT: 20919d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_SLE: 20929d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return CI->getValue().isNegative() ? 20939d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands ConstantInt::getFalse(CI->getContext()) : 20949d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands ConstantInt::getTrue(CI->getContext()); 20959d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 20969d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // If LHS is non-negative then LHS <u RHS. If LHS is negative then 20979d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands // LHS >u RHS. 20989d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_UGT: 20999d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_UGE: 210094c22716d60ff5edf6a98a3c67e0faa001be1142Sylvestre Ledru // Comparison is true iff the LHS <s 0. 21019d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (MaxRecurse) 21029d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (Value *V = SimplifyICmpInst(ICmpInst::ICMP_SLT, SrcOp, 21039d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands Constant::getNullValue(SrcTy), 21040aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse-1)) 21059d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return V; 21069d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands break; 21079d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_ULT: 21089d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands case ICmpInst::ICMP_ULE: 210994c22716d60ff5edf6a98a3c67e0faa001be1142Sylvestre Ledru // Comparison is true iff the LHS >=s 0. 21109d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (MaxRecurse) 21119d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands if (Value *V = SimplifyICmpInst(ICmpInst::ICMP_SGE, SrcOp, 21129d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands Constant::getNullValue(SrcTy), 21130aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse-1)) 21149d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands return V; 21159d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands break; 21169d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 21179d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 21189d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 21199d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 21209d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands } 21219d32f60a6f7dbd8e83187481cd2ae0a2f3e726ceDuncan Sands 212252fb846578714d14bbde9b28884a6a8729217677Duncan Sands // Special logic for binary operators. 212352fb846578714d14bbde9b28884a6a8729217677Duncan Sands BinaryOperator *LBO = dyn_cast<BinaryOperator>(LHS); 212452fb846578714d14bbde9b28884a6a8729217677Duncan Sands BinaryOperator *RBO = dyn_cast<BinaryOperator>(RHS); 212552fb846578714d14bbde9b28884a6a8729217677Duncan Sands if (MaxRecurse && (LBO || RBO)) { 212652fb846578714d14bbde9b28884a6a8729217677Duncan Sands // Analyze the case when either LHS or RHS is an add instruction. 212752fb846578714d14bbde9b28884a6a8729217677Duncan Sands Value *A = 0, *B = 0, *C = 0, *D = 0; 212852fb846578714d14bbde9b28884a6a8729217677Duncan Sands // LHS = A + B (or A and B are null); RHS = C + D (or C and D are null). 212952fb846578714d14bbde9b28884a6a8729217677Duncan Sands bool NoLHSWrapProblem = false, NoRHSWrapProblem = false; 213052fb846578714d14bbde9b28884a6a8729217677Duncan Sands if (LBO && LBO->getOpcode() == Instruction::Add) { 213152fb846578714d14bbde9b28884a6a8729217677Duncan Sands A = LBO->getOperand(0); B = LBO->getOperand(1); 213252fb846578714d14bbde9b28884a6a8729217677Duncan Sands NoLHSWrapProblem = ICmpInst::isEquality(Pred) || 213352fb846578714d14bbde9b28884a6a8729217677Duncan Sands (CmpInst::isUnsigned(Pred) && LBO->hasNoUnsignedWrap()) || 213452fb846578714d14bbde9b28884a6a8729217677Duncan Sands (CmpInst::isSigned(Pred) && LBO->hasNoSignedWrap()); 213552fb846578714d14bbde9b28884a6a8729217677Duncan Sands } 213652fb846578714d14bbde9b28884a6a8729217677Duncan Sands if (RBO && RBO->getOpcode() == Instruction::Add) { 213752fb846578714d14bbde9b28884a6a8729217677Duncan Sands C = RBO->getOperand(0); D = RBO->getOperand(1); 213852fb846578714d14bbde9b28884a6a8729217677Duncan Sands NoRHSWrapProblem = ICmpInst::isEquality(Pred) || 213952fb846578714d14bbde9b28884a6a8729217677Duncan Sands (CmpInst::isUnsigned(Pred) && RBO->hasNoUnsignedWrap()) || 214052fb846578714d14bbde9b28884a6a8729217677Duncan Sands (CmpInst::isSigned(Pred) && RBO->hasNoSignedWrap()); 214152fb846578714d14bbde9b28884a6a8729217677Duncan Sands } 214252fb846578714d14bbde9b28884a6a8729217677Duncan Sands 214352fb846578714d14bbde9b28884a6a8729217677Duncan Sands // icmp (X+Y), X -> icmp Y, 0 for equalities or if there is no overflow. 214452fb846578714d14bbde9b28884a6a8729217677Duncan Sands if ((A == RHS || B == RHS) && NoLHSWrapProblem) 214552fb846578714d14bbde9b28884a6a8729217677Duncan Sands if (Value *V = SimplifyICmpInst(Pred, A == RHS ? B : A, 214652fb846578714d14bbde9b28884a6a8729217677Duncan Sands Constant::getNullValue(RHS->getType()), 21470aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse-1)) 214852fb846578714d14bbde9b28884a6a8729217677Duncan Sands return V; 214952fb846578714d14bbde9b28884a6a8729217677Duncan Sands 215052fb846578714d14bbde9b28884a6a8729217677Duncan Sands // icmp X, (X+Y) -> icmp 0, Y for equalities or if there is no overflow. 215152fb846578714d14bbde9b28884a6a8729217677Duncan Sands if ((C == LHS || D == LHS) && NoRHSWrapProblem) 215252fb846578714d14bbde9b28884a6a8729217677Duncan Sands if (Value *V = SimplifyICmpInst(Pred, 215352fb846578714d14bbde9b28884a6a8729217677Duncan Sands Constant::getNullValue(LHS->getType()), 21540aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands C == LHS ? D : C, Q, MaxRecurse-1)) 215552fb846578714d14bbde9b28884a6a8729217677Duncan Sands return V; 215652fb846578714d14bbde9b28884a6a8729217677Duncan Sands 215752fb846578714d14bbde9b28884a6a8729217677Duncan Sands // icmp (X+Y), (X+Z) -> icmp Y,Z for equalities or if there is no overflow. 215852fb846578714d14bbde9b28884a6a8729217677Duncan Sands if (A && C && (A == C || A == D || B == C || B == D) && 215952fb846578714d14bbde9b28884a6a8729217677Duncan Sands NoLHSWrapProblem && NoRHSWrapProblem) { 216052fb846578714d14bbde9b28884a6a8729217677Duncan Sands // Determine Y and Z in the form icmp (X+Y), (X+Z). 2161aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands Value *Y, *Z; 2162aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands if (A == C) { 21634f0dfbb454ea8110459e2d1ee5f92e74cb3e8a5cDuncan Sands // C + B == C + D -> B == D 2164aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands Y = B; 2165aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands Z = D; 2166aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands } else if (A == D) { 21674f0dfbb454ea8110459e2d1ee5f92e74cb3e8a5cDuncan Sands // D + B == C + D -> B == C 2168aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands Y = B; 2169aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands Z = C; 2170aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands } else if (B == C) { 21714f0dfbb454ea8110459e2d1ee5f92e74cb3e8a5cDuncan Sands // A + C == C + D -> A == D 2172aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands Y = A; 2173aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands Z = D; 21744f0dfbb454ea8110459e2d1ee5f92e74cb3e8a5cDuncan Sands } else { 21754f0dfbb454ea8110459e2d1ee5f92e74cb3e8a5cDuncan Sands assert(B == D); 21764f0dfbb454ea8110459e2d1ee5f92e74cb3e8a5cDuncan Sands // A + D == C + D -> A == C 2177aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands Y = A; 2178aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands Z = C; 2179aceb03eb58778ae4a2811d2c2bbd23e0e0cf49b5Duncan Sands } 21800aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyICmpInst(Pred, Y, Z, Q, MaxRecurse-1)) 218152fb846578714d14bbde9b28884a6a8729217677Duncan Sands return V; 218252fb846578714d14bbde9b28884a6a8729217677Duncan Sands } 218352fb846578714d14bbde9b28884a6a8729217677Duncan Sands } 218452fb846578714d14bbde9b28884a6a8729217677Duncan Sands 218584dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky if (LBO && match(LBO, m_URem(m_Value(), m_Specific(RHS)))) { 2186786792784e898f29febb3e7270d54b0e21e3c904Nick Lewycky bool KnownNonNegative, KnownNegative; 218788cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky switch (Pred) { 218888cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky default: 218988cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky break; 2190786792784e898f29febb3e7270d54b0e21e3c904Nick Lewycky case ICmpInst::ICMP_SGT: 2191786792784e898f29febb3e7270d54b0e21e3c904Nick Lewycky case ICmpInst::ICMP_SGE: 21920aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands ComputeSignBit(LHS, KnownNonNegative, KnownNegative, Q.TD); 2193786792784e898f29febb3e7270d54b0e21e3c904Nick Lewycky if (!KnownNonNegative) 2194786792784e898f29febb3e7270d54b0e21e3c904Nick Lewycky break; 2195786792784e898f29febb3e7270d54b0e21e3c904Nick Lewycky // fall-through 219688cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky case ICmpInst::ICMP_EQ: 219788cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky case ICmpInst::ICMP_UGT: 219888cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky case ICmpInst::ICMP_UGE: 2199f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 2200786792784e898f29febb3e7270d54b0e21e3c904Nick Lewycky case ICmpInst::ICMP_SLT: 2201786792784e898f29febb3e7270d54b0e21e3c904Nick Lewycky case ICmpInst::ICMP_SLE: 22020aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands ComputeSignBit(LHS, KnownNonNegative, KnownNegative, Q.TD); 2203786792784e898f29febb3e7270d54b0e21e3c904Nick Lewycky if (!KnownNonNegative) 2204786792784e898f29febb3e7270d54b0e21e3c904Nick Lewycky break; 2205786792784e898f29febb3e7270d54b0e21e3c904Nick Lewycky // fall-through 220688cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky case ICmpInst::ICMP_NE: 220788cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky case ICmpInst::ICMP_ULT: 220888cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky case ICmpInst::ICMP_ULE: 2209f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 221088cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky } 221188cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky } 221284dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky if (RBO && match(RBO, m_URem(m_Value(), m_Specific(LHS)))) { 221384dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky bool KnownNonNegative, KnownNegative; 221484dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky switch (Pred) { 221584dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky default: 221684dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky break; 221784dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky case ICmpInst::ICMP_SGT: 221884dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky case ICmpInst::ICMP_SGE: 22190aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands ComputeSignBit(RHS, KnownNonNegative, KnownNegative, Q.TD); 222084dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky if (!KnownNonNegative) 222184dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky break; 222284dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky // fall-through 2223a0e2f38b25ce7c51c22ed40d8a315fe1dd98926dNick Lewycky case ICmpInst::ICMP_NE: 222484dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky case ICmpInst::ICMP_UGT: 222584dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky case ICmpInst::ICMP_UGE: 2226f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 222784dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky case ICmpInst::ICMP_SLT: 222884dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky case ICmpInst::ICMP_SLE: 22290aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands ComputeSignBit(RHS, KnownNonNegative, KnownNegative, Q.TD); 223084dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky if (!KnownNonNegative) 223184dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky break; 223284dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky // fall-through 2233a0e2f38b25ce7c51c22ed40d8a315fe1dd98926dNick Lewycky case ICmpInst::ICMP_EQ: 223484dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky case ICmpInst::ICMP_ULT: 223584dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky case ICmpInst::ICMP_ULE: 2236f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 223784dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky } 223884dd4fa2e36f72050f5c46577359f5df0467e3e4Nick Lewycky } 223988cd0aadb2849a259e8656b0ff8439ef660db7c5Nick Lewycky 2240c65c747bc4ee7d3ca8463d33708bbb2aed38a809Duncan Sands // x udiv y <=u x. 2241c65c747bc4ee7d3ca8463d33708bbb2aed38a809Duncan Sands if (LBO && match(LBO, m_UDiv(m_Specific(RHS), m_Value()))) { 2242c65c747bc4ee7d3ca8463d33708bbb2aed38a809Duncan Sands // icmp pred (X /u Y), X 2243c65c747bc4ee7d3ca8463d33708bbb2aed38a809Duncan Sands if (Pred == ICmpInst::ICMP_UGT) 2244c65c747bc4ee7d3ca8463d33708bbb2aed38a809Duncan Sands return getFalse(ITy); 2245c65c747bc4ee7d3ca8463d33708bbb2aed38a809Duncan Sands if (Pred == ICmpInst::ICMP_ULE) 2246c65c747bc4ee7d3ca8463d33708bbb2aed38a809Duncan Sands return getTrue(ITy); 2247c65c747bc4ee7d3ca8463d33708bbb2aed38a809Duncan Sands } 2248c65c747bc4ee7d3ca8463d33708bbb2aed38a809Duncan Sands 224958bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky if (MaxRecurse && LBO && RBO && LBO->getOpcode() == RBO->getOpcode() && 225058bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky LBO->getOperand(1) == RBO->getOperand(1)) { 225158bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky switch (LBO->getOpcode()) { 225258bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky default: break; 225358bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky case Instruction::UDiv: 225458bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky case Instruction::LShr: 225558bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky if (ICmpInst::isSigned(Pred)) 225658bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky break; 225758bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky // fall-through 225858bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky case Instruction::SDiv: 225958bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky case Instruction::AShr: 2260b6e7cd655c6ee119dbeacc321ee92387f983edb0Eli Friedman if (!LBO->isExact() || !RBO->isExact()) 226158bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky break; 226258bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky if (Value *V = SimplifyICmpInst(Pred, LBO->getOperand(0), 22630aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RBO->getOperand(0), Q, MaxRecurse-1)) 226458bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky return V; 226558bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky break; 226658bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky case Instruction::Shl: { 2267c9d904ee2ca36ab6238ed93c7ad2ea67b5fd0a23Duncan Sands bool NUW = LBO->hasNoUnsignedWrap() && RBO->hasNoUnsignedWrap(); 226858bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky bool NSW = LBO->hasNoSignedWrap() && RBO->hasNoSignedWrap(); 226958bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky if (!NUW && !NSW) 227058bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky break; 227158bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky if (!NSW && ICmpInst::isSigned(Pred)) 227258bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky break; 227358bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky if (Value *V = SimplifyICmpInst(Pred, LBO->getOperand(0), 22740aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RBO->getOperand(0), Q, MaxRecurse-1)) 227558bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky return V; 227658bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky break; 227758bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky } 227858bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky } 227958bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky } 228058bfcdbcf6a7c1cac0187f7c6beb3afe9d8f5411Nick Lewycky 2281ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // Simplify comparisons involving max/min. 2282ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands Value *A, *B; 2283ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands CmpInst::Predicate P = CmpInst::BAD_ICMP_PREDICATE; 228494c22716d60ff5edf6a98a3c67e0faa001be1142Sylvestre Ledru CmpInst::Predicate EqP; // Chosen so that "A == max/min(A,B)" iff "A EqP B". 2285ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands 22868140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // Signed variants on "max(a,b)>=a -> true". 2287ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (match(LHS, m_SMax(m_Value(A), m_Value(B))) && (A == RHS || B == RHS)) { 2288ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (A != RHS) std::swap(A, B); // smax(A, B) pred A. 228994c22716d60ff5edf6a98a3c67e0faa001be1142Sylvestre Ledru EqP = CmpInst::ICMP_SGE; // "A == smax(A, B)" iff "A sge B". 2290ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // We analyze this as smax(A, B) pred A. 2291ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands P = Pred; 2292ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } else if (match(RHS, m_SMax(m_Value(A), m_Value(B))) && 2293ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands (A == LHS || B == LHS)) { 2294ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (A != LHS) std::swap(A, B); // A pred smax(A, B). 229594c22716d60ff5edf6a98a3c67e0faa001be1142Sylvestre Ledru EqP = CmpInst::ICMP_SGE; // "A == smax(A, B)" iff "A sge B". 2296ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // We analyze this as smax(A, B) swapped-pred A. 2297ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands P = CmpInst::getSwappedPredicate(Pred); 2298ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } else if (match(LHS, m_SMin(m_Value(A), m_Value(B))) && 2299ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands (A == RHS || B == RHS)) { 2300ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (A != RHS) std::swap(A, B); // smin(A, B) pred A. 230194c22716d60ff5edf6a98a3c67e0faa001be1142Sylvestre Ledru EqP = CmpInst::ICMP_SLE; // "A == smin(A, B)" iff "A sle B". 2302ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // We analyze this as smax(-A, -B) swapped-pred -A. 2303ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // Note that we do not need to actually form -A or -B thanks to EqP. 2304ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands P = CmpInst::getSwappedPredicate(Pred); 2305ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } else if (match(RHS, m_SMin(m_Value(A), m_Value(B))) && 2306ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands (A == LHS || B == LHS)) { 2307ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (A != LHS) std::swap(A, B); // A pred smin(A, B). 230894c22716d60ff5edf6a98a3c67e0faa001be1142Sylvestre Ledru EqP = CmpInst::ICMP_SLE; // "A == smin(A, B)" iff "A sle B". 2309ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // We analyze this as smax(-A, -B) pred -A. 2310ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // Note that we do not need to actually form -A or -B thanks to EqP. 2311ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands P = Pred; 2312ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } 2313ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (P != CmpInst::BAD_ICMP_PREDICATE) { 2314ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // Cases correspond to "max(A, B) p A". 2315ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands switch (P) { 2316ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands default: 2317ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands break; 2318ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands case CmpInst::ICMP_EQ: 2319ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands case CmpInst::ICMP_SLE: 2320e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // Equivalent to "A EqP B". This may be the same as the condition tested 2321e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // in the max/min; if so, we can just return that. 2322e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (Value *V = ExtractEquivalentCondition(LHS, EqP, A, B)) 2323e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return V; 2324e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (Value *V = ExtractEquivalentCondition(RHS, EqP, A, B)) 2325e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return V; 2326e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // Otherwise, see if "A EqP B" simplifies. 2327ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (MaxRecurse) 23280aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyICmpInst(EqP, A, B, Q, MaxRecurse-1)) 2329ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands return V; 2330ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands break; 2331ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands case CmpInst::ICMP_NE: 2332e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands case CmpInst::ICMP_SGT: { 2333e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands CmpInst::Predicate InvEqP = CmpInst::getInversePredicate(EqP); 2334e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // Equivalent to "A InvEqP B". This may be the same as the condition 2335e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // tested in the max/min; if so, we can just return that. 2336e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (Value *V = ExtractEquivalentCondition(LHS, InvEqP, A, B)) 2337e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return V; 2338e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (Value *V = ExtractEquivalentCondition(RHS, InvEqP, A, B)) 2339e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return V; 2340e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // Otherwise, see if "A InvEqP B" simplifies. 2341ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (MaxRecurse) 23420aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyICmpInst(InvEqP, A, B, Q, MaxRecurse-1)) 2343ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands return V; 2344ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands break; 2345e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands } 2346ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands case CmpInst::ICMP_SGE: 2347ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // Always true. 2348f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 2349ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands case CmpInst::ICMP_SLT: 2350ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // Always false. 2351f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 2352ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } 2353ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } 2354ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands 23558140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // Unsigned variants on "max(a,b)>=a -> true". 2356ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands P = CmpInst::BAD_ICMP_PREDICATE; 2357ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (match(LHS, m_UMax(m_Value(A), m_Value(B))) && (A == RHS || B == RHS)) { 2358ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (A != RHS) std::swap(A, B); // umax(A, B) pred A. 235994c22716d60ff5edf6a98a3c67e0faa001be1142Sylvestre Ledru EqP = CmpInst::ICMP_UGE; // "A == umax(A, B)" iff "A uge B". 2360ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // We analyze this as umax(A, B) pred A. 2361ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands P = Pred; 2362ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } else if (match(RHS, m_UMax(m_Value(A), m_Value(B))) && 2363ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands (A == LHS || B == LHS)) { 2364ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (A != LHS) std::swap(A, B); // A pred umax(A, B). 236594c22716d60ff5edf6a98a3c67e0faa001be1142Sylvestre Ledru EqP = CmpInst::ICMP_UGE; // "A == umax(A, B)" iff "A uge B". 2366ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // We analyze this as umax(A, B) swapped-pred A. 2367ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands P = CmpInst::getSwappedPredicate(Pred); 2368ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } else if (match(LHS, m_UMin(m_Value(A), m_Value(B))) && 2369ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands (A == RHS || B == RHS)) { 2370ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (A != RHS) std::swap(A, B); // umin(A, B) pred A. 237194c22716d60ff5edf6a98a3c67e0faa001be1142Sylvestre Ledru EqP = CmpInst::ICMP_ULE; // "A == umin(A, B)" iff "A ule B". 2372ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // We analyze this as umax(-A, -B) swapped-pred -A. 2373ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // Note that we do not need to actually form -A or -B thanks to EqP. 2374ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands P = CmpInst::getSwappedPredicate(Pred); 2375ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } else if (match(RHS, m_UMin(m_Value(A), m_Value(B))) && 2376ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands (A == LHS || B == LHS)) { 2377ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (A != LHS) std::swap(A, B); // A pred umin(A, B). 237894c22716d60ff5edf6a98a3c67e0faa001be1142Sylvestre Ledru EqP = CmpInst::ICMP_ULE; // "A == umin(A, B)" iff "A ule B". 2379ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // We analyze this as umax(-A, -B) pred -A. 2380ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // Note that we do not need to actually form -A or -B thanks to EqP. 2381ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands P = Pred; 2382ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } 2383ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (P != CmpInst::BAD_ICMP_PREDICATE) { 2384ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // Cases correspond to "max(A, B) p A". 2385ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands switch (P) { 2386ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands default: 2387ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands break; 2388ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands case CmpInst::ICMP_EQ: 2389ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands case CmpInst::ICMP_ULE: 2390e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // Equivalent to "A EqP B". This may be the same as the condition tested 2391e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // in the max/min; if so, we can just return that. 2392e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (Value *V = ExtractEquivalentCondition(LHS, EqP, A, B)) 2393e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return V; 2394e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (Value *V = ExtractEquivalentCondition(RHS, EqP, A, B)) 2395e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return V; 2396e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // Otherwise, see if "A EqP B" simplifies. 2397ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (MaxRecurse) 23980aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyICmpInst(EqP, A, B, Q, MaxRecurse-1)) 2399ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands return V; 2400ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands break; 2401ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands case CmpInst::ICMP_NE: 2402e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands case CmpInst::ICMP_UGT: { 2403e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands CmpInst::Predicate InvEqP = CmpInst::getInversePredicate(EqP); 2404e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // Equivalent to "A InvEqP B". This may be the same as the condition 2405e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // tested in the max/min; if so, we can just return that. 2406e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (Value *V = ExtractEquivalentCondition(LHS, InvEqP, A, B)) 2407e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return V; 2408e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands if (Value *V = ExtractEquivalentCondition(RHS, InvEqP, A, B)) 2409e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands return V; 2410e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands // Otherwise, see if "A InvEqP B" simplifies. 2411ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands if (MaxRecurse) 24120aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyICmpInst(InvEqP, A, B, Q, MaxRecurse-1)) 2413ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands return V; 2414ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands break; 2415e864b5b840c58d0b04324082ec94a7156743ed60Duncan Sands } 2416ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands case CmpInst::ICMP_UGE: 2417ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // Always true. 2418f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 2419ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands case CmpInst::ICMP_ULT: 2420ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands // Always false. 2421f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 2422ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } 2423ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands } 2424ad20681cdeaf72383891b153b925624aa585be4dDuncan Sands 24258140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // Variants on "max(x,y) >= min(x,z)". 24268140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands Value *C, *D; 24278140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands if (match(LHS, m_SMax(m_Value(A), m_Value(B))) && 24288140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands match(RHS, m_SMin(m_Value(C), m_Value(D))) && 24298140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands (A == C || A == D || B == C || B == D)) { 24308140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // max(x, ?) pred min(x, ?). 24318140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands if (Pred == CmpInst::ICMP_SGE) 24328140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // Always true. 2433f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 24348140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands if (Pred == CmpInst::ICMP_SLT) 24358140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // Always false. 2436f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 24378140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands } else if (match(LHS, m_SMin(m_Value(A), m_Value(B))) && 24388140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands match(RHS, m_SMax(m_Value(C), m_Value(D))) && 24398140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands (A == C || A == D || B == C || B == D)) { 24408140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // min(x, ?) pred max(x, ?). 24418140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands if (Pred == CmpInst::ICMP_SLE) 24428140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // Always true. 2443f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 24448140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands if (Pred == CmpInst::ICMP_SGT) 24458140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // Always false. 2446f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 24478140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands } else if (match(LHS, m_UMax(m_Value(A), m_Value(B))) && 24488140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands match(RHS, m_UMin(m_Value(C), m_Value(D))) && 24498140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands (A == C || A == D || B == C || B == D)) { 24508140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // max(x, ?) pred min(x, ?). 24518140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands if (Pred == CmpInst::ICMP_UGE) 24528140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // Always true. 2453f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 24548140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands if (Pred == CmpInst::ICMP_ULT) 24558140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // Always false. 2456f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 24578140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands } else if (match(LHS, m_UMin(m_Value(A), m_Value(B))) && 24588140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands match(RHS, m_UMax(m_Value(C), m_Value(D))) && 24598140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands (A == C || A == D || B == C || B == D)) { 24608140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // min(x, ?) pred max(x, ?). 24618140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands if (Pred == CmpInst::ICMP_ULE) 24628140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // Always true. 2463f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getTrue(ITy); 24648140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands if (Pred == CmpInst::ICMP_UGT) 24658140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands // Always false. 2466f56138d4aeb6d271cb353d70a794fa1525d892c3Duncan Sands return getFalse(ITy); 24678140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands } 24688140ad32ce45281ed2bc4f6ca388a6ed9f806550Duncan Sands 246958725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth // Simplify comparisons of related pointers using a powerful, recursive 247058725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth // GEP-walk when we have target data available.. 247158725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth if (Q.TD && LHS->getType()->isPointerTy() && RHS->getType()->isPointerTy()) 247258725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth if (Constant *C = computePointerICmp(*Q.TD, Pred, LHS, RHS)) 247358725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth return C; 247458725a66c02865686c70132e8b9bd231eb66da63Chandler Carruth 2475f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky if (GetElementPtrInst *GLHS = dyn_cast<GetElementPtrInst>(LHS)) { 2476f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky if (GEPOperator *GRHS = dyn_cast<GEPOperator>(RHS)) { 2477f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky if (GLHS->getPointerOperand() == GRHS->getPointerOperand() && 2478f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky GLHS->hasAllConstantIndices() && GRHS->hasAllConstantIndices() && 2479f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky (ICmpInst::isEquality(Pred) || 2480f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky (GLHS->isInBounds() && GRHS->isInBounds() && 2481f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky Pred == ICmpInst::getSignedPredicate(Pred)))) { 2482f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // The bases are equal and the indices are constant. Build a constant 2483f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // expression GEP with the same indices and a null base pointer to see 2484f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky // what constant folding can make out of it. 2485f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky Constant *Null = Constant::getNullValue(GLHS->getPointerOperandType()); 2486f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky SmallVector<Value *, 4> IndicesLHS(GLHS->idx_begin(), GLHS->idx_end()); 2487f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky Constant *NewLHS = ConstantExpr::getGetElementPtr(Null, IndicesLHS); 2488f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky 2489f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky SmallVector<Value *, 4> IndicesRHS(GRHS->idx_begin(), GRHS->idx_end()); 2490f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky Constant *NewRHS = ConstantExpr::getGetElementPtr(Null, IndicesRHS); 2491f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky return ConstantExpr::getICmp(Pred, NewLHS, NewRHS); 2492f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky } 2493f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky } 2494f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky } 2495f7087ea5088d58e81f08a3eeb39ba46fa18d0fd4Nick Lewycky 24961ac7c9979a2d723ff4649ffad58df02732872a5fDuncan Sands // If the comparison is with the result of a select instruction, check whether 24971ac7c9979a2d723ff4649ffad58df02732872a5fDuncan Sands // comparing with either branch of the select always yields the same value. 24980312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (isa<SelectInst>(LHS) || isa<SelectInst>(RHS)) 24990aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadCmpOverSelect(Pred, LHS, RHS, Q, MaxRecurse)) 2500a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands return V; 2501a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 2502a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // If the comparison is with the result of a phi instruction, check whether 2503a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // doing the compare with each incoming phi value yields a common result. 25040312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (isa<PHINode>(LHS) || isa<PHINode>(RHS)) 25050aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadCmpOverPHI(Pred, LHS, RHS, Q, MaxRecurse)) 25063bbb0cc42b67b4bf2c488285666999963bab0f7eDuncan Sands return V; 25071ac7c9979a2d723ff4649ffad58df02732872a5fDuncan Sands 25089dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner return 0; 25099dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner} 25109dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner 2511a74a58c83be492b7d5b7383656f049909394cff4Duncan SandsValue *llvm::SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, 25123574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, 2513618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 2514618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const DominatorTree *DT) { 25150aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyICmpInst(Predicate, LHS, RHS, Query (TD, TLI, DT), 25160aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RecursionLimit); 2517a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands} 2518a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 25199dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner/// SimplifyFCmpInst - Given operands for an FCmpInst, see if we can 25209dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner/// fold the result. If not, this returns null. 2521a74a58c83be492b7d5b7383656f049909394cff4Duncan Sandsstatic Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS, 25220aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 25239dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner CmpInst::Predicate Pred = (CmpInst::Predicate)Predicate; 25249dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner assert(CmpInst::isFPPredicate(Pred) && "Not an FP compare!"); 25259dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner 2526d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (Constant *CLHS = dyn_cast<Constant>(LHS)) { 25279dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner if (Constant *CRHS = dyn_cast<Constant>(RHS)) 25280aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ConstantFoldCompareInstOperands(Pred, CLHS, CRHS, Q.TD, Q.TLI); 252912a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 2530d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner // If we have a constant, make sure it is on the RHS. 2531d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner std::swap(LHS, RHS); 2532d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner Pred = CmpInst::getSwappedPredicate(Pred); 2533d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner } 253412a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 2535210c5d4880b525e064088b6fec713260128c16ebChris Lattner // Fold trivial predicates. 2536210c5d4880b525e064088b6fec713260128c16ebChris Lattner if (Pred == FCmpInst::FCMP_FALSE) 2537210c5d4880b525e064088b6fec713260128c16ebChris Lattner return ConstantInt::get(GetCompareTy(LHS), 0); 2538210c5d4880b525e064088b6fec713260128c16ebChris Lattner if (Pred == FCmpInst::FCMP_TRUE) 2539210c5d4880b525e064088b6fec713260128c16ebChris Lattner return ConstantInt::get(GetCompareTy(LHS), 1); 2540210c5d4880b525e064088b6fec713260128c16ebChris Lattner 2541210c5d4880b525e064088b6fec713260128c16ebChris Lattner if (isa<UndefValue>(RHS)) // fcmp pred X, undef -> undef 2542210c5d4880b525e064088b6fec713260128c16ebChris Lattner return UndefValue::get(GetCompareTy(LHS)); 2543210c5d4880b525e064088b6fec713260128c16ebChris Lattner 2544210c5d4880b525e064088b6fec713260128c16ebChris Lattner // fcmp x,x -> true/false. Not all compares are foldable. 2545124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (LHS == RHS) { 2546210c5d4880b525e064088b6fec713260128c16ebChris Lattner if (CmpInst::isTrueWhenEqual(Pred)) 2547210c5d4880b525e064088b6fec713260128c16ebChris Lattner return ConstantInt::get(GetCompareTy(LHS), 1); 2548210c5d4880b525e064088b6fec713260128c16ebChris Lattner if (CmpInst::isFalseWhenEqual(Pred)) 2549210c5d4880b525e064088b6fec713260128c16ebChris Lattner return ConstantInt::get(GetCompareTy(LHS), 0); 2550210c5d4880b525e064088b6fec713260128c16ebChris Lattner } 255112a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 2552210c5d4880b525e064088b6fec713260128c16ebChris Lattner // Handle fcmp with constant RHS 2553210c5d4880b525e064088b6fec713260128c16ebChris Lattner if (Constant *RHSC = dyn_cast<Constant>(RHS)) { 2554210c5d4880b525e064088b6fec713260128c16ebChris Lattner // If the constant is a nan, see if we can fold the comparison based on it. 2555210c5d4880b525e064088b6fec713260128c16ebChris Lattner if (ConstantFP *CFP = dyn_cast<ConstantFP>(RHSC)) { 2556210c5d4880b525e064088b6fec713260128c16ebChris Lattner if (CFP->getValueAPF().isNaN()) { 2557210c5d4880b525e064088b6fec713260128c16ebChris Lattner if (FCmpInst::isOrdered(Pred)) // True "if ordered and foo" 2558210c5d4880b525e064088b6fec713260128c16ebChris Lattner return ConstantInt::getFalse(CFP->getContext()); 2559210c5d4880b525e064088b6fec713260128c16ebChris Lattner assert(FCmpInst::isUnordered(Pred) && 2560210c5d4880b525e064088b6fec713260128c16ebChris Lattner "Comparison must be either ordered or unordered!"); 2561210c5d4880b525e064088b6fec713260128c16ebChris Lattner // True if unordered. 2562210c5d4880b525e064088b6fec713260128c16ebChris Lattner return ConstantInt::getTrue(CFP->getContext()); 2563210c5d4880b525e064088b6fec713260128c16ebChris Lattner } 25646b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman // Check whether the constant is an infinity. 25656b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman if (CFP->getValueAPF().isInfinity()) { 25666b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman if (CFP->getValueAPF().isNegative()) { 25676b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman switch (Pred) { 25686b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman case FCmpInst::FCMP_OLT: 25696b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman // No value is ordered and less than negative infinity. 25706b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman return ConstantInt::getFalse(CFP->getContext()); 25716b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman case FCmpInst::FCMP_UGE: 25726b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman // All values are unordered with or at least negative infinity. 25736b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman return ConstantInt::getTrue(CFP->getContext()); 25746b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman default: 25756b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman break; 25766b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman } 25776b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman } else { 25786b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman switch (Pred) { 25796b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman case FCmpInst::FCMP_OGT: 25806b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman // No value is ordered and greater than infinity. 25816b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman return ConstantInt::getFalse(CFP->getContext()); 25826b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman case FCmpInst::FCMP_ULE: 25836b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman // All values are unordered with and at most infinity. 25846b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman return ConstantInt::getTrue(CFP->getContext()); 25856b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman default: 25866b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman break; 25876b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman } 25886b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman } 25896b617a7213e159097a7e5c7216ed9b04921de4e1Dan Gohman } 2590210c5d4880b525e064088b6fec713260128c16ebChris Lattner } 2591210c5d4880b525e064088b6fec713260128c16ebChris Lattner } 259212a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 259392826def593df7a422c7b07f09342febce81ddd3Duncan Sands // If the comparison is with the result of a select instruction, check whether 259492826def593df7a422c7b07f09342febce81ddd3Duncan Sands // comparing with either branch of the select always yields the same value. 25950312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (isa<SelectInst>(LHS) || isa<SelectInst>(RHS)) 25960aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadCmpOverSelect(Pred, LHS, RHS, Q, MaxRecurse)) 2597a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands return V; 2598a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 2599a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // If the comparison is with the result of a phi instruction, check whether 2600a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // doing the compare with each incoming phi value yields a common result. 26010312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (isa<PHINode>(LHS) || isa<PHINode>(RHS)) 26020aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadCmpOverPHI(Pred, LHS, RHS, Q, MaxRecurse)) 26033bbb0cc42b67b4bf2c488285666999963bab0f7eDuncan Sands return V; 260492826def593df7a422c7b07f09342febce81ddd3Duncan Sands 26059f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner return 0; 26069f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner} 26079f3c25aeb3df77a336693308dc0f19a4983c99afChris Lattner 2608a74a58c83be492b7d5b7383656f049909394cff4Duncan SandsValue *llvm::SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS, 26093574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, 2610618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 2611618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const DominatorTree *DT) { 26120aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyFCmpInst(Predicate, LHS, RHS, Query (TD, TLI, DT), 26130aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RecursionLimit); 2614a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands} 2615a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 2616047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner/// SimplifySelectInst - Given operands for a SelectInst, see if we can fold 2617047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner/// the result. If not, this returns null. 26180aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifySelectInst(Value *CondVal, Value *TrueVal, 26190aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Value *FalseVal, const Query &Q, 26200aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands unsigned MaxRecurse) { 2621047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner // select true, X, Y -> X 2622047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner // select false, X, Y -> Y 2623047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner if (ConstantInt *CB = dyn_cast<ConstantInt>(CondVal)) 2624047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner return CB->getZExtValue() ? TrueVal : FalseVal; 262512a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 2626047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner // select C, X, X -> X 2627124708d9b47cc53cb11d8bfed75b241b6eec86d4Duncan Sands if (TrueVal == FalseVal) 2628047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner return TrueVal; 262912a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 2630047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner if (isa<UndefValue>(CondVal)) { // select undef, X, Y -> X or Y 2631047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner if (isa<Constant>(TrueVal)) 2632047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner return TrueVal; 2633047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner return FalseVal; 2634047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner } 263568c0dbc14fb7599987fb3e27be4e12c1ac36535eDan Gohman if (isa<UndefValue>(TrueVal)) // select C, undef, X -> X 263668c0dbc14fb7599987fb3e27be4e12c1ac36535eDan Gohman return FalseVal; 263768c0dbc14fb7599987fb3e27be4e12c1ac36535eDan Gohman if (isa<UndefValue>(FalseVal)) // select C, X, undef -> X 263868c0dbc14fb7599987fb3e27be4e12c1ac36535eDan Gohman return TrueVal; 263912a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 2640047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner return 0; 2641047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner} 2642047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner 26430aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan SandsValue *llvm::SimplifySelectInst(Value *Cond, Value *TrueVal, Value *FalseVal, 26443574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, 26450aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const TargetLibraryInfo *TLI, 26460aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const DominatorTree *DT) { 26470aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifySelectInst(Cond, TrueVal, FalseVal, Query (TD, TLI, DT), 26480aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RecursionLimit); 26490aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands} 26500aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands 2651c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner/// SimplifyGEPInst - Given operands for an GetElementPtrInst, see if we can 2652c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner/// fold the result. If not, this returns null. 26530aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyGEPInst(ArrayRef<Value *> Ops, const Query &Q, unsigned) { 265485bbff6c94695f07cc1a9765b4d384ed18d2fd7cDuncan Sands // The type of the GEP pointer operand. 26551608769abeb1430dc34f31ffac0d9850f99ae36aNadav Rotem PointerType *PtrTy = dyn_cast<PointerType>(Ops[0]->getType()); 26561608769abeb1430dc34f31ffac0d9850f99ae36aNadav Rotem // The GEP pointer operand is not a pointer, it's a vector of pointers. 26571608769abeb1430dc34f31ffac0d9850f99ae36aNadav Rotem if (!PtrTy) 26581608769abeb1430dc34f31ffac0d9850f99ae36aNadav Rotem return 0; 265985bbff6c94695f07cc1a9765b4d384ed18d2fd7cDuncan Sands 2660c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner // getelementptr P -> P. 2661b9b54ebfed02f0654897d37e8a4448d3f8087558Jay Foad if (Ops.size() == 1) 2662c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner return Ops[0]; 2663c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner 266485bbff6c94695f07cc1a9765b4d384ed18d2fd7cDuncan Sands if (isa<UndefValue>(Ops[0])) { 266585bbff6c94695f07cc1a9765b4d384ed18d2fd7cDuncan Sands // Compute the (pointer) type returned by the GEP instruction. 2666a9203109f4ac95aa7e9624f2838e3d89623ec902Jay Foad Type *LastType = GetElementPtrInst::getIndexedType(PtrTy, Ops.slice(1)); 2667db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *GEPTy = PointerType::get(LastType, PtrTy->getAddressSpace()); 266885bbff6c94695f07cc1a9765b4d384ed18d2fd7cDuncan Sands return UndefValue::get(GEPTy); 266985bbff6c94695f07cc1a9765b4d384ed18d2fd7cDuncan Sands } 2670c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner 2671b9b54ebfed02f0654897d37e8a4448d3f8087558Jay Foad if (Ops.size() == 2) { 2672e60d79faf7ef7bc4847f9e5d067af00b98dced7bDuncan Sands // getelementptr P, 0 -> P. 2673c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner if (ConstantInt *C = dyn_cast<ConstantInt>(Ops[1])) 2674c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner if (C->isZero()) 2675c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner return Ops[0]; 2676e60d79faf7ef7bc4847f9e5d067af00b98dced7bDuncan Sands // getelementptr P, N -> P if P points to a type of zero size. 26770aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Q.TD) { 2678db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty = PtrTy->getElementType(); 26790aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Ty->isSized() && Q.TD->getTypeAllocSize(Ty) == 0) 2680e60d79faf7ef7bc4847f9e5d067af00b98dced7bDuncan Sands return Ops[0]; 2681e60d79faf7ef7bc4847f9e5d067af00b98dced7bDuncan Sands } 2682e60d79faf7ef7bc4847f9e5d067af00b98dced7bDuncan Sands } 268312a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 2684c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner // Check to see if this is constant foldable. 2685b9b54ebfed02f0654897d37e8a4448d3f8087558Jay Foad for (unsigned i = 0, e = Ops.size(); i != e; ++i) 2686c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner if (!isa<Constant>(Ops[i])) 2687c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner return 0; 268812a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 2689dab3d29605a5c83db41b28176273ef55961120c1Jay Foad return ConstantExpr::getGetElementPtr(cast<Constant>(Ops[0]), Ops.slice(1)); 2690c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner} 2691c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner 26923574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifyGEPInst(ArrayRef<Value *> Ops, const DataLayout *TD, 26930aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const TargetLibraryInfo *TLI, 26940aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const DominatorTree *DT) { 26950aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyGEPInst(Ops, Query (TD, TLI, DT), RecursionLimit); 26960aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands} 26970aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands 2698dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands/// SimplifyInsertValueInst - Given operands for an InsertValueInst, see if we 2699dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands/// can fold the result. If not, this returns null. 27000aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyInsertValueInst(Value *Agg, Value *Val, 27010aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands ArrayRef<unsigned> Idxs, const Query &Q, 27020aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands unsigned) { 2703dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands if (Constant *CAgg = dyn_cast<Constant>(Agg)) 2704dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands if (Constant *CVal = dyn_cast<Constant>(Val)) 2705dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands return ConstantFoldInsertValueInstruction(CAgg, CVal, Idxs); 2706dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands 2707dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands // insertvalue x, undef, n -> x 2708dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands if (match(Val, m_Undef())) 2709dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands return Agg; 2710dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands 2711dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands // insertvalue x, (extractvalue y, n), n 2712dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands if (ExtractValueInst *EV = dyn_cast<ExtractValueInst>(Val)) 2713ae707bd5594e52a8b385760f99ff58aa8fede948Benjamin Kramer if (EV->getAggregateOperand()->getType() == Agg->getType() && 2714ae707bd5594e52a8b385760f99ff58aa8fede948Benjamin Kramer EV->getIndices() == Idxs) { 2715dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands // insertvalue undef, (extractvalue y, n), n -> y 2716dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands if (match(Agg, m_Undef())) 2717dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands return EV->getAggregateOperand(); 2718dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands 2719dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands // insertvalue y, (extractvalue y, n), n -> y 2720dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands if (Agg == EV->getAggregateOperand()) 2721dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands return Agg; 2722dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands } 2723dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands 2724dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands return 0; 2725dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands} 2726dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands 27270aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan SandsValue *llvm::SimplifyInsertValueInst(Value *Agg, Value *Val, 27280aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands ArrayRef<unsigned> Idxs, 27293574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, 27300aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const TargetLibraryInfo *TLI, 27310aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const DominatorTree *DT) { 27320aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyInsertValueInst(Agg, Val, Idxs, Query (TD, TLI, DT), 27330aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RecursionLimit); 27340aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands} 27350aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands 2736ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands/// SimplifyPHINode - See if we can fold the given phi. If not, returns null. 27370aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sandsstatic Value *SimplifyPHINode(PHINode *PN, const Query &Q) { 2738ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands // If all of the PHI's incoming values are the same then replace the PHI node 2739ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands // with the common value. 2740ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands Value *CommonValue = 0; 2741ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands bool HasUndefInput = false; 2742ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) { 2743ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands Value *Incoming = PN->getIncomingValue(i); 2744ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands // If the incoming value is the phi node itself, it can safely be skipped. 2745ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands if (Incoming == PN) continue; 2746ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands if (isa<UndefValue>(Incoming)) { 2747ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands // Remember that we saw an undef value, but otherwise ignore them. 2748ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands HasUndefInput = true; 2749ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands continue; 2750ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands } 2751ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands if (CommonValue && Incoming != CommonValue) 2752ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands return 0; // Not the same, bail out. 2753ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands CommonValue = Incoming; 2754ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands } 2755ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands 2756ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands // If CommonValue is null then all of the incoming values were either undef or 2757ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands // equal to the phi node itself. 2758ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands if (!CommonValue) 2759ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands return UndefValue::get(PN->getType()); 2760ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands 2761ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands // If we have a PHI node like phi(X, undef, X), where X is defined by some 2762ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands // instruction, we cannot return X as the result of the PHI node unless it 2763ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands // dominates the PHI block. 2764ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands if (HasUndefInput) 27650aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ValueDominatesPHI(CommonValue, PN, Q.DT) ? CommonValue : 0; 2766ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands 2767ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands return CommonValue; 2768ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands} 2769ff10341183adf74760e6118a55cbd1debf50f90fDuncan Sands 2770bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sandsstatic Value *SimplifyTruncInst(Value *Op, Type *Ty, const Query &Q, unsigned) { 2771bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands if (Constant *C = dyn_cast<Constant>(Op)) 2772bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands return ConstantFoldInstOperands(Instruction::Trunc, Ty, C, Q.TD, Q.TLI); 2773bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands 2774bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands return 0; 2775bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands} 2776bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands 27773574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifyTruncInst(Value *Op, Type *Ty, const DataLayout *TD, 2778bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands const TargetLibraryInfo *TLI, 2779bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands const DominatorTree *DT) { 2780bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands return ::SimplifyTruncInst(Op, Ty, Query (TD, TLI, DT), RecursionLimit); 2781bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands} 2782bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands 2783d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner//=== Helper functions for higher up the class hierarchy. 27849dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner 2785d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner/// SimplifyBinOp - Given operands for a BinaryOperator, see if we can 2786d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner/// fold the result. If not, this returns null. 2787a74a58c83be492b7d5b7383656f049909394cff4Duncan Sandsstatic Value *SimplifyBinOp(unsigned Opcode, Value *LHS, Value *RHS, 27880aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 2789d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner switch (Opcode) { 279081a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner case Instruction::Add: 2791ffeb98ad3becfbb8e26270ef8751e37e4b6b0cd1Duncan Sands return SimplifyAddInst(LHS, RHS, /*isNSW*/false, /*isNUW*/false, 27920aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse); 2793d0a0d221da55f5e2d97909991d77e7ab91e75426Michael Ilseman case Instruction::FAdd: 2794d0a0d221da55f5e2d97909991d77e7ab91e75426Michael Ilseman return SimplifyFAddInst(LHS, RHS, FastMathFlags(), Q, MaxRecurse); 2795d0a0d221da55f5e2d97909991d77e7ab91e75426Michael Ilseman 279681a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner case Instruction::Sub: 2797ffeb98ad3becfbb8e26270ef8751e37e4b6b0cd1Duncan Sands return SimplifySubInst(LHS, RHS, /*isNSW*/false, /*isNUW*/false, 27980aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse); 2799d0a0d221da55f5e2d97909991d77e7ab91e75426Michael Ilseman case Instruction::FSub: 2800d0a0d221da55f5e2d97909991d77e7ab91e75426Michael Ilseman return SimplifyFSubInst(LHS, RHS, FastMathFlags(), Q, MaxRecurse); 2801d0a0d221da55f5e2d97909991d77e7ab91e75426Michael Ilseman 28020aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands case Instruction::Mul: return SimplifyMulInst (LHS, RHS, Q, MaxRecurse); 2803d0a0d221da55f5e2d97909991d77e7ab91e75426Michael Ilseman case Instruction::FMul: 2804d0a0d221da55f5e2d97909991d77e7ab91e75426Michael Ilseman return SimplifyFMulInst (LHS, RHS, FastMathFlags(), Q, MaxRecurse); 28050aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands case Instruction::SDiv: return SimplifySDivInst(LHS, RHS, Q, MaxRecurse); 28060aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands case Instruction::UDiv: return SimplifyUDivInst(LHS, RHS, Q, MaxRecurse); 28070aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands case Instruction::FDiv: return SimplifyFDivInst(LHS, RHS, Q, MaxRecurse); 28080aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands case Instruction::SRem: return SimplifySRemInst(LHS, RHS, Q, MaxRecurse); 28090aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands case Instruction::URem: return SimplifyURemInst(LHS, RHS, Q, MaxRecurse); 28100aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands case Instruction::FRem: return SimplifyFRemInst(LHS, RHS, Q, MaxRecurse); 281181a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner case Instruction::Shl: 2812ffeb98ad3becfbb8e26270ef8751e37e4b6b0cd1Duncan Sands return SimplifyShlInst(LHS, RHS, /*isNSW*/false, /*isNUW*/false, 28130aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q, MaxRecurse); 281481a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner case Instruction::LShr: 28150aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return SimplifyLShrInst(LHS, RHS, /*isExact*/false, Q, MaxRecurse); 281681a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner case Instruction::AShr: 28170aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return SimplifyAShrInst(LHS, RHS, /*isExact*/false, Q, MaxRecurse); 28180aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands case Instruction::And: return SimplifyAndInst(LHS, RHS, Q, MaxRecurse); 28190aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands case Instruction::Or: return SimplifyOrInst (LHS, RHS, Q, MaxRecurse); 28200aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands case Instruction::Xor: return SimplifyXorInst(LHS, RHS, Q, MaxRecurse); 2821d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner default: 2822d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (Constant *CLHS = dyn_cast<Constant>(LHS)) 2823d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner if (Constant *CRHS = dyn_cast<Constant>(RHS)) { 2824d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner Constant *COps[] = {CLHS, CRHS}; 28250aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ConstantFoldInstOperands(Opcode, LHS->getType(), COps, Q.TD, 28260aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Q.TLI); 2827d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner } 2828b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 2829566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands // If the operation is associative, try some generic simplifications. 2830566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands if (Instruction::isAssociative(Opcode)) 28310aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = SimplifyAssociativeBinOp(Opcode, LHS, RHS, Q, MaxRecurse)) 2832566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands return V; 2833566edb04b890cebca8f2eefa37af7371a1e756c9Duncan Sands 28340aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands // If the operation is with the result of a select instruction check whether 2835b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands // operating on either branch of the select always yields the same value. 28360312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (isa<SelectInst>(LHS) || isa<SelectInst>(RHS)) 28370aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverSelect(Opcode, LHS, RHS, Q, MaxRecurse)) 2838a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands return V; 2839a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 2840a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // If the operation is with the result of a phi instruction, check whether 2841a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands // operating on all incoming values of the phi always yields the same value. 28420312a93693abc2eb682b2b101c889959888fd883Duncan Sands if (isa<PHINode>(LHS) || isa<PHINode>(RHS)) 28430aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands if (Value *V = ThreadBinOpOverPHI(Opcode, LHS, RHS, Q, MaxRecurse)) 2844b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands return V; 2845b2cbdc35ba85c04df15b0e991d9be371691ab08cDuncan Sands 2846d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner return 0; 2847d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner } 2848d06094f0682f2ede03caff4892b1a57469896d48Chris Lattner} 28499dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner 285012a86f5b3199e72e6d967781acc76340f5920e46Duncan SandsValue *llvm::SimplifyBinOp(unsigned Opcode, Value *LHS, Value *RHS, 28513574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, const TargetLibraryInfo *TLI, 2852618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const DominatorTree *DT) { 28530aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyBinOp(Opcode, LHS, RHS, Query (TD, TLI, DT), RecursionLimit); 2854a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands} 2855a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands 28569dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner/// SimplifyCmpInst - Given operands for a CmpInst, see if we can 28579dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner/// fold the result. 2858a74a58c83be492b7d5b7383656f049909394cff4Duncan Sandsstatic Value *SimplifyCmpInst(unsigned Predicate, Value *LHS, Value *RHS, 28590aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands const Query &Q, unsigned MaxRecurse) { 28609dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner if (CmpInst::isIntPredicate((CmpInst::Predicate)Predicate)) 28610aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return SimplifyICmpInst(Predicate, LHS, RHS, Q, MaxRecurse); 28620aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return SimplifyFCmpInst(Predicate, LHS, RHS, Q, MaxRecurse); 28639dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner} 28649dbb42944c4d7caddab21016b24cca31019a3fafChris Lattner 2865a74a58c83be492b7d5b7383656f049909394cff4Duncan SandsValue *llvm::SimplifyCmpInst(unsigned Predicate, Value *LHS, Value *RHS, 28663574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, const TargetLibraryInfo *TLI, 2867618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const DominatorTree *DT) { 28680aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands return ::SimplifyCmpInst(Predicate, LHS, RHS, Query (TD, TLI, DT), 28690aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands RecursionLimit); 2870a74a58c83be492b7d5b7383656f049909394cff4Duncan Sands} 2871e34537856a544c83513e390ac9552a8bc3823346Chris Lattner 2872c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruthtemplate <typename IterTy> 2873e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruthstatic Value *SimplifyCall(Value *V, IterTy ArgBegin, IterTy ArgEnd, 2874c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth const Query &Q, unsigned MaxRecurse) { 2875e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth Type *Ty = V->getType(); 2876c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth if (PointerType *PTy = dyn_cast<PointerType>(Ty)) 2877c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth Ty = PTy->getElementType(); 2878c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth FunctionType *FTy = cast<FunctionType>(Ty); 2879c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth 288071d050315704c23b235594d3fad5268c12d825e3Dan Gohman // call undef -> undef 2881e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth if (isa<UndefValue>(V)) 2882c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth return UndefValue::get(FTy->getReturnType()); 288371d050315704c23b235594d3fad5268c12d825e3Dan Gohman 2884e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth Function *F = dyn_cast<Function>(V); 2885e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth if (!F) 2886e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth return 0; 2887e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth 2888e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth if (!canConstantFoldCallTo(F)) 2889e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth return 0; 2890e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth 2891e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth SmallVector<Constant *, 4> ConstantArgs; 2892e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth ConstantArgs.reserve(ArgEnd - ArgBegin); 2893e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth for (IterTy I = ArgBegin, E = ArgEnd; I != E; ++I) { 2894e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth Constant *C = dyn_cast<Constant>(*I); 2895e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth if (!C) 2896e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth return 0; 2897e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth ConstantArgs.push_back(C); 2898e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth } 2899e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth 2900e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth return ConstantFoldCall(F, ConstantArgs, Q.TLI); 290171d050315704c23b235594d3fad5268c12d825e3Dan Gohman} 290271d050315704c23b235594d3fad5268c12d825e3Dan Gohman 2903e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler CarruthValue *llvm::SimplifyCall(Value *V, User::op_iterator ArgBegin, 2904c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth User::op_iterator ArgEnd, const DataLayout *TD, 2905c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth const TargetLibraryInfo *TLI, 2906c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth const DominatorTree *DT) { 2907e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth return ::SimplifyCall(V, ArgBegin, ArgEnd, Query(TD, TLI, DT), 2908c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth RecursionLimit); 2909c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth} 2910c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth 2911e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler CarruthValue *llvm::SimplifyCall(Value *V, ArrayRef<Value *> Args, 2912c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth const DataLayout *TD, const TargetLibraryInfo *TLI, 2913c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth const DominatorTree *DT) { 2914e949aa1c91132094a9073c82a8aef729fa8c9ecaChandler Carruth return ::SimplifyCall(V, Args.begin(), Args.end(), Query(TD, TLI, DT), 2915c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth RecursionLimit); 2916c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth} 2917c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth 2918e34537856a544c83513e390ac9552a8bc3823346Chris Lattner/// SimplifyInstruction - See if we can compute a simplified version of this 2919e34537856a544c83513e390ac9552a8bc3823346Chris Lattner/// instruction. If not, this returns null. 29203574eca1b02600bac4e625297f4ecf745f4c4f32Micah VillmowValue *llvm::SimplifyInstruction(Instruction *I, const DataLayout *TD, 2921618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier const TargetLibraryInfo *TLI, 2922eff0581583ef10e2872e9baf537a04b67d992101Duncan Sands const DominatorTree *DT) { 2923d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands Value *Result; 2924d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands 2925e34537856a544c83513e390ac9552a8bc3823346Chris Lattner switch (I->getOpcode()) { 2926e34537856a544c83513e390ac9552a8bc3823346Chris Lattner default: 2927618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier Result = ConstantFoldInstruction(I, TD, TLI); 2928d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands break; 292909ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman case Instruction::FAdd: 293009ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman Result = SimplifyFAddInst(I->getOperand(0), I->getOperand(1), 293109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman I->getFastMathFlags(), TD, TLI, DT); 293209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman break; 29338aee8efc0c2e387faa7dae39fdf613a22889b566Chris Lattner case Instruction::Add: 2934d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands Result = SimplifyAddInst(I->getOperand(0), I->getOperand(1), 2935d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands cast<BinaryOperator>(I)->hasNoSignedWrap(), 2936d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands cast<BinaryOperator>(I)->hasNoUnsignedWrap(), 2937618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier TD, TLI, DT); 2938d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands break; 293909ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman case Instruction::FSub: 294009ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman Result = SimplifyFSubInst(I->getOperand(0), I->getOperand(1), 294109ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman I->getFastMathFlags(), TD, TLI, DT); 294209ee250e728ccdb7afc6354d777f8319c5a0465cMichael Ilseman break; 2943fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands case Instruction::Sub: 2944fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands Result = SimplifySubInst(I->getOperand(0), I->getOperand(1), 2945fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands cast<BinaryOperator>(I)->hasNoSignedWrap(), 2946fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands cast<BinaryOperator>(I)->hasNoUnsignedWrap(), 2947618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier TD, TLI, DT); 2948fea3b218d61708ea3577f4ef14c8f7677a94db95Duncan Sands break; 2949eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman case Instruction::FMul: 2950eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman Result = SimplifyFMulInst(I->getOperand(0), I->getOperand(1), 2951eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman I->getFastMathFlags(), TD, TLI, DT); 2952eb61c920f12cacee38815bf10821d2f294b66f3aMichael Ilseman break; 295382fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands case Instruction::Mul: 2954618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier Result = SimplifyMulInst(I->getOperand(0), I->getOperand(1), TD, TLI, DT); 295582fdab335881cd90f8f7ab3ad1f1ca0bb3ee886aDuncan Sands break; 2956593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands case Instruction::SDiv: 2957618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier Result = SimplifySDivInst(I->getOperand(0), I->getOperand(1), TD, TLI, DT); 2958593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands break; 2959593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands case Instruction::UDiv: 2960618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier Result = SimplifyUDivInst(I->getOperand(0), I->getOperand(1), TD, TLI, DT); 2961593faa53fa6d89841e601cc4571d143a6a05f0b4Duncan Sands break; 29621fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel case Instruction::FDiv: 2963618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier Result = SimplifyFDivInst(I->getOperand(0), I->getOperand(1), TD, TLI, DT); 29641fca2c32cc99197215d3fd32a4ad05214c74edd1Frits van Bommel break; 2965f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands case Instruction::SRem: 2966618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier Result = SimplifySRemInst(I->getOperand(0), I->getOperand(1), TD, TLI, DT); 2967f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands break; 2968f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands case Instruction::URem: 2969618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier Result = SimplifyURemInst(I->getOperand(0), I->getOperand(1), TD, TLI, DT); 2970f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands break; 2971f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands case Instruction::FRem: 2972618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier Result = SimplifyFRemInst(I->getOperand(0), I->getOperand(1), TD, TLI, DT); 2973f24ed77d2416b66178d8ff1d807858dfab37ca18Duncan Sands break; 2974c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands case Instruction::Shl: 297581a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner Result = SimplifyShlInst(I->getOperand(0), I->getOperand(1), 297681a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner cast<BinaryOperator>(I)->hasNoSignedWrap(), 297781a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner cast<BinaryOperator>(I)->hasNoUnsignedWrap(), 2978618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier TD, TLI, DT); 2979c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands break; 2980c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands case Instruction::LShr: 298181a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner Result = SimplifyLShrInst(I->getOperand(0), I->getOperand(1), 298281a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner cast<BinaryOperator>(I)->isExact(), 2983618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier TD, TLI, DT); 2984c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands break; 2985c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands case Instruction::AShr: 298681a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner Result = SimplifyAShrInst(I->getOperand(0), I->getOperand(1), 298781a0dc911586c77421c2255aa417dc9b350b9e20Chris Lattner cast<BinaryOperator>(I)->isExact(), 2988618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier TD, TLI, DT); 2989c43cee3fbb3098f0647e50dd2c13bc55b027a228Duncan Sands break; 2990e34537856a544c83513e390ac9552a8bc3823346Chris Lattner case Instruction::And: 2991618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier Result = SimplifyAndInst(I->getOperand(0), I->getOperand(1), TD, TLI, DT); 2992d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands break; 2993e34537856a544c83513e390ac9552a8bc3823346Chris Lattner case Instruction::Or: 2994618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier Result = SimplifyOrInst(I->getOperand(0), I->getOperand(1), TD, TLI, DT); 2995d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands break; 29962b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands case Instruction::Xor: 2997618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier Result = SimplifyXorInst(I->getOperand(0), I->getOperand(1), TD, TLI, DT); 29982b749870d0488c3b049edf5d0c8875f56f5b1bedDuncan Sands break; 2999e34537856a544c83513e390ac9552a8bc3823346Chris Lattner case Instruction::ICmp: 3000d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands Result = SimplifyICmpInst(cast<ICmpInst>(I)->getPredicate(), 3001618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier I->getOperand(0), I->getOperand(1), TD, TLI, DT); 3002d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands break; 3003e34537856a544c83513e390ac9552a8bc3823346Chris Lattner case Instruction::FCmp: 3004d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands Result = SimplifyFCmpInst(cast<FCmpInst>(I)->getPredicate(), 3005618c1dbd293d15ee19f61b1156ab8086ad28311aChad Rosier I->getOperand(0), I->getOperand(1), TD, TLI, DT); 3006d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands break; 3007047542669a20505fc7c5f2d93caa5610aa3db2c5Chris Lattner case Instruction::Select: 3008d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands Result = SimplifySelectInst(I->getOperand(0), I->getOperand(1), 30090aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands I->getOperand(2), TD, TLI, DT); 3010d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands break; 3011c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner case Instruction::GetElementPtr: { 3012c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner SmallVector<Value*, 8> Ops(I->op_begin(), I->op_end()); 30130aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Result = SimplifyGEPInst(Ops, TD, TLI, DT); 3014d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands break; 3015c514c1f5218b8fe7499a0b9a4737860344cf4c43Chris Lattner } 3016dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands case Instruction::InsertValue: { 3017dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands InsertValueInst *IV = cast<InsertValueInst>(I); 3018dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands Result = SimplifyInsertValueInst(IV->getAggregateOperand(), 3019dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands IV->getInsertedValueOperand(), 30200aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands IV->getIndices(), TD, TLI, DT); 3021dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands break; 3022dabc2806726a286b00313419fac8461ebe0f774cDuncan Sands } 3023cd6636c737a82949ad13db2d0d918af6424fb78bDuncan Sands case Instruction::PHI: 30240aa85eb231dc76bcabcd35f6dc9a50536f607df3Duncan Sands Result = SimplifyPHINode(cast<PHINode>(I), Query (TD, TLI, DT)); 3025d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands break; 3026c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth case Instruction::Call: { 3027c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth CallSite CS(cast<CallInst>(I)); 3028c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth Result = SimplifyCall(CS.getCalledValue(), CS.arg_begin(), CS.arg_end(), 3029c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth TD, TLI, DT); 303071d050315704c23b235594d3fad5268c12d825e3Dan Gohman break; 3031c98bd9f1a79adffe73acd337b6f7f9afa6bae078Chandler Carruth } 3032bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands case Instruction::Trunc: 3033bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands Result = SimplifyTruncInst(I->getOperand(0), I->getType(), TD, TLI, DT); 3034bd0fe5642544d4ec3aee1ede7af60c006bae5cbfDuncan Sands break; 3035e34537856a544c83513e390ac9552a8bc3823346Chris Lattner } 3036d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands 3037d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands /// If called on unreachable code, the above logic may report that the 3038d261dc650a01ac5c51ab10f97f1e35aa6a770721Duncan Sands /// instruction simplified to itself. Make life easier for users by 3039f8b1a5ea9602bb65a5cf59d3d34f2851a08cdc3eDuncan Sands /// detecting that case here, returning a safe value instead. 3040f8b1a5ea9602bb65a5cf59d3d34f2851a08cdc3eDuncan Sands return Result == I ? UndefValue::get(I->getType()) : Result; 3041e34537856a544c83513e390ac9552a8bc3823346Chris Lattner} 3042e34537856a544c83513e390ac9552a8bc3823346Chris Lattner 30436b980541df5846ad335c377c8803b517968daee2Chandler Carruth/// \brief Implementation of recursive simplification through an instructions 30446b980541df5846ad335c377c8803b517968daee2Chandler Carruth/// uses. 304540d8c28b27377199b7465ba2c5a2c59c6fd12fa9Chris Lattner/// 30466b980541df5846ad335c377c8803b517968daee2Chandler Carruth/// This is the common implementation of the recursive simplification routines. 30476b980541df5846ad335c377c8803b517968daee2Chandler Carruth/// If we have a pre-simplified value in 'SimpleV', that is forcibly used to 30486b980541df5846ad335c377c8803b517968daee2Chandler Carruth/// replace the instruction 'I'. Otherwise, we simply add 'I' to the list of 30496b980541df5846ad335c377c8803b517968daee2Chandler Carruth/// instructions to process and attempt to simplify it using 30506b980541df5846ad335c377c8803b517968daee2Chandler Carruth/// InstructionSimplify. 30516b980541df5846ad335c377c8803b517968daee2Chandler Carruth/// 30526b980541df5846ad335c377c8803b517968daee2Chandler Carruth/// This routine returns 'true' only when *it* simplifies something. The passed 30536b980541df5846ad335c377c8803b517968daee2Chandler Carruth/// in simplified value does not count toward this. 30546b980541df5846ad335c377c8803b517968daee2Chandler Carruthstatic bool replaceAndRecursivelySimplifyImpl(Instruction *I, Value *SimpleV, 30553574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, 30566b980541df5846ad335c377c8803b517968daee2Chandler Carruth const TargetLibraryInfo *TLI, 30576b980541df5846ad335c377c8803b517968daee2Chandler Carruth const DominatorTree *DT) { 30586b980541df5846ad335c377c8803b517968daee2Chandler Carruth bool Simplified = false; 30596231d5be410e2d7967352b29ad01522fda15680dChandler Carruth SmallSetVector<Instruction *, 8> Worklist; 30606b980541df5846ad335c377c8803b517968daee2Chandler Carruth 30616b980541df5846ad335c377c8803b517968daee2Chandler Carruth // If we have an explicit value to collapse to, do that round of the 30626b980541df5846ad335c377c8803b517968daee2Chandler Carruth // simplification loop by hand initially. 30636b980541df5846ad335c377c8803b517968daee2Chandler Carruth if (SimpleV) { 30646b980541df5846ad335c377c8803b517968daee2Chandler Carruth for (Value::use_iterator UI = I->use_begin(), UE = I->use_end(); UI != UE; 30656b980541df5846ad335c377c8803b517968daee2Chandler Carruth ++UI) 3066c5b785b91c922bbb3d5adb4b042c976bebe00e4dChandler Carruth if (*UI != I) 30676231d5be410e2d7967352b29ad01522fda15680dChandler Carruth Worklist.insert(cast<Instruction>(*UI)); 30686b980541df5846ad335c377c8803b517968daee2Chandler Carruth 30696b980541df5846ad335c377c8803b517968daee2Chandler Carruth // Replace the instruction with its simplified value. 30706b980541df5846ad335c377c8803b517968daee2Chandler Carruth I->replaceAllUsesWith(SimpleV); 30716b980541df5846ad335c377c8803b517968daee2Chandler Carruth 30726b980541df5846ad335c377c8803b517968daee2Chandler Carruth // Gracefully handle edge cases where the instruction is not wired into any 30736b980541df5846ad335c377c8803b517968daee2Chandler Carruth // parent block. 30746b980541df5846ad335c377c8803b517968daee2Chandler Carruth if (I->getParent()) 30756b980541df5846ad335c377c8803b517968daee2Chandler Carruth I->eraseFromParent(); 30766b980541df5846ad335c377c8803b517968daee2Chandler Carruth } else { 30776231d5be410e2d7967352b29ad01522fda15680dChandler Carruth Worklist.insert(I); 30786b980541df5846ad335c377c8803b517968daee2Chandler Carruth } 307912a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 30806231d5be410e2d7967352b29ad01522fda15680dChandler Carruth // Note that we must test the size on each iteration, the worklist can grow. 30816231d5be410e2d7967352b29ad01522fda15680dChandler Carruth for (unsigned Idx = 0; Idx != Worklist.size(); ++Idx) { 30826231d5be410e2d7967352b29ad01522fda15680dChandler Carruth I = Worklist[Idx]; 308312a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 30846b980541df5846ad335c377c8803b517968daee2Chandler Carruth // See if this instruction simplifies. 30856b980541df5846ad335c377c8803b517968daee2Chandler Carruth SimpleV = SimplifyInstruction(I, TD, TLI, DT); 30866b980541df5846ad335c377c8803b517968daee2Chandler Carruth if (!SimpleV) 30876b980541df5846ad335c377c8803b517968daee2Chandler Carruth continue; 30886b980541df5846ad335c377c8803b517968daee2Chandler Carruth 30896b980541df5846ad335c377c8803b517968daee2Chandler Carruth Simplified = true; 30906b980541df5846ad335c377c8803b517968daee2Chandler Carruth 30916b980541df5846ad335c377c8803b517968daee2Chandler Carruth // Stash away all the uses of the old instruction so we can check them for 30926b980541df5846ad335c377c8803b517968daee2Chandler Carruth // recursive simplifications after a RAUW. This is cheaper than checking all 30936b980541df5846ad335c377c8803b517968daee2Chandler Carruth // uses of To on the recursive step in most cases. 30946b980541df5846ad335c377c8803b517968daee2Chandler Carruth for (Value::use_iterator UI = I->use_begin(), UE = I->use_end(); UI != UE; 30956b980541df5846ad335c377c8803b517968daee2Chandler Carruth ++UI) 30966231d5be410e2d7967352b29ad01522fda15680dChandler Carruth Worklist.insert(cast<Instruction>(*UI)); 309712a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 30986b980541df5846ad335c377c8803b517968daee2Chandler Carruth // Replace the instruction with its simplified value. 30996b980541df5846ad335c377c8803b517968daee2Chandler Carruth I->replaceAllUsesWith(SimpleV); 31006b980541df5846ad335c377c8803b517968daee2Chandler Carruth 31016b980541df5846ad335c377c8803b517968daee2Chandler Carruth // Gracefully handle edge cases where the instruction is not wired into any 31026b980541df5846ad335c377c8803b517968daee2Chandler Carruth // parent block. 31036b980541df5846ad335c377c8803b517968daee2Chandler Carruth if (I->getParent()) 31046b980541df5846ad335c377c8803b517968daee2Chandler Carruth I->eraseFromParent(); 310540d8c28b27377199b7465ba2c5a2c59c6fd12fa9Chris Lattner } 31066b980541df5846ad335c377c8803b517968daee2Chandler Carruth return Simplified; 31076b980541df5846ad335c377c8803b517968daee2Chandler Carruth} 310812a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 31096b980541df5846ad335c377c8803b517968daee2Chandler Carruthbool llvm::recursivelySimplifyInstruction(Instruction *I, 31103574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, 31116b980541df5846ad335c377c8803b517968daee2Chandler Carruth const TargetLibraryInfo *TLI, 31126b980541df5846ad335c377c8803b517968daee2Chandler Carruth const DominatorTree *DT) { 31136b980541df5846ad335c377c8803b517968daee2Chandler Carruth return replaceAndRecursivelySimplifyImpl(I, 0, TD, TLI, DT); 31146b980541df5846ad335c377c8803b517968daee2Chandler Carruth} 311512a86f5b3199e72e6d967781acc76340f5920e46Duncan Sands 31166b980541df5846ad335c377c8803b517968daee2Chandler Carruthbool llvm::replaceAndRecursivelySimplify(Instruction *I, Value *SimpleV, 31173574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD, 31186b980541df5846ad335c377c8803b517968daee2Chandler Carruth const TargetLibraryInfo *TLI, 31196b980541df5846ad335c377c8803b517968daee2Chandler Carruth const DominatorTree *DT) { 31206b980541df5846ad335c377c8803b517968daee2Chandler Carruth assert(I != SimpleV && "replaceAndRecursivelySimplify(X,X) is not valid!"); 31216b980541df5846ad335c377c8803b517968daee2Chandler Carruth assert(SimpleV && "Must provide a simplified value."); 31226b980541df5846ad335c377c8803b517968daee2Chandler Carruth return replaceAndRecursivelySimplifyImpl(I, SimpleV, TD, TLI, DT); 312340d8c28b27377199b7465ba2c5a2c59c6fd12fa9Chris Lattner} 3124