ScalarEvolutionExpander.cpp revision f8d0578e4cbd5922696c92f5068c5513d8e8d60e
136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman//===- ScalarEvolutionExpander.cpp - Scalar Evolution Analysis --*- C++ -*-===// 236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman// 336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman// The LLVM Compiler Infrastructure 436f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman// 54ee451de366474b9c228b4e5fa573795a715216dChris Lattner// This file is distributed under the University of Illinois Open Source 64ee451de366474b9c228b4e5fa573795a715216dChris Lattner// License. See LICENSE.TXT for details. 736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman// 836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman//===----------------------------------------------------------------------===// 936f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman// 1036f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman// This file contains the implementation of the scalar evolution expander, 1136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman// which is used to generate the code corresponding to a given scalar evolution 1236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman// expression. 1336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman// 1436f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman//===----------------------------------------------------------------------===// 1536f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 1636f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman#include "llvm/Analysis/ScalarEvolutionExpander.h" 17e81561909d128c6e2d8033cb5465a49b2596b26aBill Wendling#include "llvm/Analysis/LoopInfo.h" 188d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen#include "llvm/IntrinsicInst.h" 1976f600b205606a055ec35e7d3fd1a99602329d67Owen Anderson#include "llvm/LLVMContext.h" 205be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman#include "llvm/Target/TargetData.h" 214d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman#include "llvm/ADT/STLExtras.h" 2236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begemanusing namespace llvm; 2336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 24267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman/// InsertNoopCastOfTo - Insert a cast of V to the specified type, 25267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman/// which must be possible with a noop cast, doing what we can to share 26267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman/// the casts. 27267a385342f2e7388f178b327dd87c5f29afd51bDan GohmanValue *SCEVExpander::InsertNoopCastOfTo(Value *V, const Type *Ty) { 28267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction::CastOps Op = CastInst::getCastOpcode(V, false, Ty, false); 29267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman assert((Op == Instruction::BitCast || 30267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Op == Instruction::PtrToInt || 31267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Op == Instruction::IntToPtr) && 32267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman "InsertNoopCastOfTo cannot perform non-noop casts!"); 33267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman assert(SE.getTypeSizeInBits(V->getType()) == SE.getTypeSizeInBits(Ty) && 34267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman "InsertNoopCastOfTo cannot change sizes!"); 35267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman 362d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman // Short-circuit unnecessary bitcasts. 37267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (Op == Instruction::BitCast && V->getType() == Ty) 382d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman return V; 392d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman 40f04fa483b83227c570bc58e1684ea096430a6697Dan Gohman // Short-circuit unnecessary inttoptr<->ptrtoint casts. 41267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if ((Op == Instruction::PtrToInt || Op == Instruction::IntToPtr) && 4280dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman SE.getTypeSizeInBits(Ty) == SE.getTypeSizeInBits(V->getType())) { 43af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman if (CastInst *CI = dyn_cast<CastInst>(V)) 44af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman if ((CI->getOpcode() == Instruction::PtrToInt || 45af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman CI->getOpcode() == Instruction::IntToPtr) && 46af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman SE.getTypeSizeInBits(CI->getType()) == 47af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman SE.getTypeSizeInBits(CI->getOperand(0)->getType())) 48af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman return CI->getOperand(0); 4980dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) 5080dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman if ((CE->getOpcode() == Instruction::PtrToInt || 5180dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman CE->getOpcode() == Instruction::IntToPtr) && 5280dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman SE.getTypeSizeInBits(CE->getType()) == 5380dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman SE.getTypeSizeInBits(CE->getOperand(0)->getType())) 5480dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman return CE->getOperand(0); 5580dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman } 56f04fa483b83227c570bc58e1684ea096430a6697Dan Gohman 57ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if (Constant *C = dyn_cast<Constant>(V)) 58baf3c404409d5e47b13984a7f95bfbd6d1f2e79eOwen Anderson return ConstantExpr::getCast(Op, C, Ty); 594c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman 60ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if (Argument *A = dyn_cast<Argument>(V)) { 61ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner // Check to see if there is already a cast! 62ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner for (Value::use_iterator UI = A->use_begin(), E = A->use_end(); 6340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman UI != E; ++UI) 64ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if ((*UI)->getType() == Ty) 653913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz if (CastInst *CI = dyn_cast<CastInst>(cast<Instruction>(*UI))) 66267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (CI->getOpcode() == Op) { 673913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz // If the cast isn't the first instruction of the function, move it. 6840a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (BasicBlock::iterator(CI) != 693913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz A->getParent()->getEntryBlock().begin()) { 7040a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // Recreate the cast at the beginning of the entry block. 7140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // The old cast is left in place in case it is being used 7240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // as an insert point. 7340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman Instruction *NewCI = 74267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman CastInst::Create(Op, V, Ty, "", 7540a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman A->getParent()->getEntryBlock().begin()); 7640a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman NewCI->takeName(CI); 7740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman CI->replaceAllUsesWith(NewCI); 7840a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return NewCI; 793913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz } 803913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz return CI; 81ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner } 8240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman 83267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction *I = CastInst::Create(Op, V, Ty, V->getName(), 84cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman A->getParent()->getEntryBlock().begin()); 85a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(I); 86cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return I; 87ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner } 883913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz 89ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner Instruction *I = cast<Instruction>(V); 903913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz 91ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner // Check to see if there is already a cast. If there is, use it. 92ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); 93ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner UI != E; ++UI) { 94ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if ((*UI)->getType() == Ty) 953913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz if (CastInst *CI = dyn_cast<CastInst>(cast<Instruction>(*UI))) 96267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (CI->getOpcode() == Op) { 973913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz BasicBlock::iterator It = I; ++It; 983913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz if (isa<InvokeInst>(I)) 993913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz It = cast<InvokeInst>(I)->getNormalDest()->begin(); 1003913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz while (isa<PHINode>(It)) ++It; 1013913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz if (It != BasicBlock::iterator(CI)) { 102c37e3d5d7cd9576711204dfd0240edefba2df4c7Dan Gohman // Recreate the cast after the user. 10340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // The old cast is left in place in case it is being used 10440a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // as an insert point. 105267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction *NewCI = CastInst::Create(Op, V, Ty, "", It); 10640a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman NewCI->takeName(CI); 10740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman CI->replaceAllUsesWith(NewCI); 108c37e3d5d7cd9576711204dfd0240edefba2df4c7Dan Gohman rememberInstruction(NewCI); 10940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return NewCI; 1103913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz } 111c37e3d5d7cd9576711204dfd0240edefba2df4c7Dan Gohman rememberInstruction(CI); 1123913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz return CI; 113ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner } 114ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner } 115ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner BasicBlock::iterator IP = I; ++IP; 116ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if (InvokeInst *II = dyn_cast<InvokeInst>(I)) 117ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner IP = II->getNormalDest()->begin(); 118ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner while (isa<PHINode>(IP)) ++IP; 119267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction *CI = CastInst::Create(Op, V, Ty, V->getName(), IP); 120a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(CI); 121cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return CI; 122ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner} 123ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner 1247fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner/// InsertBinop - Insert the specified binary operator, doing a small amount 1257fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner/// of work to avoid inserting an obviously redundant operation. 126267a385342f2e7388f178b327dd87c5f29afd51bDan GohmanValue *SCEVExpander::InsertBinop(Instruction::BinaryOps Opcode, 127267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *LHS, Value *RHS) { 1280f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman // Fold a binop with constant operands. 1290f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman if (Constant *CLHS = dyn_cast<Constant>(LHS)) 1300f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman if (Constant *CRHS = dyn_cast<Constant>(RHS)) 131baf3c404409d5e47b13984a7f95bfbd6d1f2e79eOwen Anderson return ConstantExpr::get(Opcode, CLHS, CRHS); 1320f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman 1337fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner // Do a quick scan to see if we have this binop nearby. If so, reuse it. 1347fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner unsigned ScanLimit = 6; 135267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator BlockBegin = Builder.GetInsertBlock()->begin(); 136267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman // Scanning starts from the last instruction before the insertion point. 137267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator IP = Builder.GetInsertPoint(); 138267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (IP != BlockBegin) { 1398a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz --IP; 1408a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz for (; ScanLimit; --IP, --ScanLimit) { 1418d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen // Don't count dbg.value against the ScanLimit, to avoid perturbing the 1428d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen // generated code. 1438d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen if (isa<DbgInfoIntrinsic>(IP)) 1448d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen ScanLimit++; 1455be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (IP->getOpcode() == (unsigned)Opcode && IP->getOperand(0) == LHS && 1465be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman IP->getOperand(1) == RHS) 1475be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return IP; 1488a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz if (IP == BlockBegin) break; 1498a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz } 1507fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner } 151267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman 152087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Save the original insertion point so we can restore it when we're done. 153087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 154087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 155087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 156087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Move the insertion point out of as many loops as we can. 157087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman while (const Loop *L = SE.LI->getLoopFor(Builder.GetInsertBlock())) { 158087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!L->isLoopInvariant(LHS) || !L->isLoopInvariant(RHS)) break; 159087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock *Preheader = L->getLoopPreheader(); 160087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!Preheader) break; 161087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 162087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Ok, move up a level. 163087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Builder.SetInsertPoint(Preheader, Preheader->getTerminator()); 164087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } 165087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 1668a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz // If we haven't found this binop, insert it. 167267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *BO = Builder.CreateBinOp(Opcode, LHS, RHS, "tmp"); 168a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(BO); 169087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 170087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Restore the original insert point. 171087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (SaveInsertBB) 172087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 173087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 174cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return BO; 1757fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner} 1767fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner 1774a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman/// FactorOutConstant - Test if S is divisible by Factor, using signed 178453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// division. If so, update S with Factor divided out and return true. 1793f46a3abeedba8d517b4182de34c821d752db058Dan Gohman/// S need not be evenly divisible if a reasonable remainder can be 1804a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman/// computed. 181453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// TODO: When ScalarEvolution gets a SCEVSDivExpr, this can be made 182453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// unnecessary; in its place, just signed-divide Ops[i] by the scale and 183453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// check to see if the divide was folded. 1840bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohmanstatic bool FactorOutConstant(const SCEV *&S, 1850bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *&Remainder, 186c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Factor, 187c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ScalarEvolution &SE, 188c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const TargetData *TD) { 189453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // Everything is divisible by one. 190c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (Factor->isOne()) 191c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 192c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 193c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // x/x == 1. 194c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (S == Factor) { 195c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman S = SE.getIntegerSCEV(1, S->getType()); 196453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return true; 197c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 198453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 199453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // For a Constant, check for a multiple of the given factor. 2004a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman if (const SCEVConstant *C = dyn_cast<SCEVConstant>(S)) { 201c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // 0/x == 0. 202c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (C->isZero()) 203453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return true; 204c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Check for divisibility. 205c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVConstant *FC = dyn_cast<SCEVConstant>(Factor)) { 206c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ConstantInt *CI = 207c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ConstantInt::get(SE.getContext(), 208c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman C->getValue()->getValue().sdiv( 209c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FC->getValue()->getValue())); 210c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If the quotient is zero and the remainder is non-zero, reject 211c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // the value at this scale. It will be considered for subsequent 212c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // smaller scales. 213c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!CI->isZero()) { 214c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Div = SE.getConstant(CI); 215c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman S = Div; 216c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Remainder = 217c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getAddExpr(Remainder, 218c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getConstant(C->getValue()->getValue().srem( 219c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FC->getValue()->getValue()))); 220c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 221c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 222453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 2234a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman } 224453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 225453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // In a Mul, check if there is a constant operand which is a multiple 226453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // of the given factor. 227c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVMulExpr *M = dyn_cast<SCEVMulExpr>(S)) { 228c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (TD) { 229c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // With TargetData, the size is known. Check if there is a constant 230c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // operand which is a multiple of the given factor. If so, we can 231c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // factor it. 232c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEVConstant *FC = cast<SCEVConstant>(Factor); 233c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVConstant *C = dyn_cast<SCEVConstant>(M->getOperand(0))) 234c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!C->getValue()->getValue().srem(FC->getValue()->getValue())) { 235f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman SmallVector<const SCEV *, 4> NewMulOps(M->op_begin(), M->op_end()); 236c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman NewMulOps[0] = 237c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getConstant(C->getValue()->getValue().sdiv( 238c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FC->getValue()->getValue())); 239c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman S = SE.getMulExpr(NewMulOps); 240c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 241c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 242c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } else { 243c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Without TargetData, check if Factor can be factored out of any of the 244c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Mul's operands. If so, we can just remove it. 245c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = 0, e = M->getNumOperands(); i != e; ++i) { 246c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *SOp = M->getOperand(i); 247c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Remainder = SE.getIntegerSCEV(0, SOp->getType()); 248c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (FactorOutConstant(SOp, Remainder, Factor, SE, TD) && 249c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Remainder->isZero()) { 250f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman SmallVector<const SCEV *, 4> NewMulOps(M->op_begin(), M->op_end()); 251c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman NewMulOps[i] = SOp; 252c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman S = SE.getMulExpr(NewMulOps); 253c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 254c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 255453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 256c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 257c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 258453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 259453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // In an AddRec, check if both start and step are divisible. 260453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman if (const SCEVAddRecExpr *A = dyn_cast<SCEVAddRecExpr>(S)) { 2610bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *Step = A->getStepRecurrence(SE); 2620bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *StepRem = SE.getIntegerSCEV(0, Step->getType()); 263c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!FactorOutConstant(Step, StepRem, Factor, SE, TD)) 2644a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman return false; 2654a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman if (!StepRem->isZero()) 2664a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman return false; 2670bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *Start = A->getStart(); 268c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!FactorOutConstant(Start, Remainder, Factor, SE, TD)) 269453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return false; 270453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman S = SE.getAddRecExpr(Start, Step, A->getLoop()); 271453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return true; 272453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 273453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 274453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return false; 275453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman} 276453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 277c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// SimplifyAddOperands - Sort and simplify a list of add operands. NumAddRecs 278c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// is the number of SCEVAddRecExprs present, which are kept at the end of 279c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// the list. 280c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// 281c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohmanstatic void SimplifyAddOperands(SmallVectorImpl<const SCEV *> &Ops, 282c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const Type *Ty, 283c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ScalarEvolution &SE) { 284c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman unsigned NumAddRecs = 0; 285c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = Ops.size(); i > 0 && isa<SCEVAddRecExpr>(Ops[i-1]); --i) 286c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ++NumAddRecs; 287c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Group Ops into non-addrecs and addrecs. 288c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 8> NoAddRecs(Ops.begin(), Ops.end() - NumAddRecs); 289c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 8> AddRecs(Ops.end() - NumAddRecs, Ops.end()); 290c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Let ScalarEvolution sort and simplify the non-addrecs list. 291c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Sum = NoAddRecs.empty() ? 292c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getIntegerSCEV(0, Ty) : 293c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getAddExpr(NoAddRecs); 294c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If it returned an add, use the operands. Otherwise it simplified 295c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // the sum into a single value, so just use that. 296f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman Ops.clear(); 297c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(Sum)) 298f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman Ops.insert(Ops.end(), Add->op_begin(), Add->op_end()); 299f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman else if (!Sum->isZero()) 300f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman Ops.push_back(Sum); 301c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Then append the addrecs. 302c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops.insert(Ops.end(), AddRecs.begin(), AddRecs.end()); 303c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman} 304c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 305c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// SplitAddRecs - Flatten a list of add operands, moving addrec start values 306c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// out to the top level. For example, convert {a + b,+,c} to a, b, {0,+,d}. 307c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// This helps expose more opportunities for folding parts of the expressions 308c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// into GEP indices. 309c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// 310c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohmanstatic void SplitAddRecs(SmallVectorImpl<const SCEV *> &Ops, 311c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const Type *Ty, 312c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ScalarEvolution &SE) { 313c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Find the addrecs. 314c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 8> AddRecs; 315c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = 0, e = Ops.size(); i != e; ++i) 316c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman while (const SCEVAddRecExpr *A = dyn_cast<SCEVAddRecExpr>(Ops[i])) { 317c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Start = A->getStart(); 318c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (Start->isZero()) break; 319c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Zero = SE.getIntegerSCEV(0, Ty); 320c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman AddRecs.push_back(SE.getAddRecExpr(Zero, 321c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman A->getStepRecurrence(SE), 322c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman A->getLoop())); 323c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(Start)) { 324c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops[i] = Zero; 325c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops.insert(Ops.end(), Add->op_begin(), Add->op_end()); 326c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman e += Add->getNumOperands(); 327c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } else { 328c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops[i] = Start; 329c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 330c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 331c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!AddRecs.empty()) { 332c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Add the addrecs onto the end of the list. 333c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops.insert(Ops.end(), AddRecs.begin(), AddRecs.end()); 334c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Resort the operand list, moving any constants to the front. 335c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SimplifyAddOperands(Ops, Ty, SE); 336c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 337c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman} 338c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 3394c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// expandAddToGEP - Expand an addition expression with a pointer type into 3404c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// a GEP instead of using ptrtoint+arithmetic+inttoptr. This helps 3414c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// BasicAliasAnalysis and other passes analyze the result. See the rules 3424c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// for getelementptr vs. inttoptr in 3434c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// http://llvm.org/docs/LangRef.html#pointeraliasing 3444c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// for details. 34513c5e35222afe0895f0c5e68aa9f22f134ea437aDan Gohman/// 3463abf905b50f33340ae81913da81b0eda96fa4616Dan Gohman/// Design note: The correctness of using getelementptr here depends on 3474c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// ScalarEvolution not recognizing inttoptr and ptrtoint operators, as 3484c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// they may introduce pointer arithmetic which may not be safely converted 3494c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// into getelementptr. 350453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// 351453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// Design note: It might seem desirable for this function to be more 352453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// loop-aware. If some of the indices are loop-invariant while others 353453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// aren't, it might seem desirable to emit multiple GEPs, keeping the 354453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// loop-invariant portions of the overall computation outside the loop. 355453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// However, there are a few reasons this is not done here. Hoisting simple 356453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// arithmetic is a low-level optimization that often isn't very 357453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// important until late in the optimization process. In fact, passes 358453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// like InstructionCombining will combine GEPs, even if it means 359453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// pushing loop-invariant computation down into loops, so even if the 360453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// GEPs were split here, the work would quickly be undone. The 361453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// LoopStrengthReduction pass, which is usually run quite late (and 362453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// after the last InstructionCombining pass), takes care of hoisting 363453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// loop-invariant portions of expressions, after considering what 364453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// can be folded using target addressing modes. 365453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// 3660bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan GohmanValue *SCEVExpander::expandAddToGEP(const SCEV *const *op_begin, 3670bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *const *op_end, 3685be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman const PointerType *PTy, 3695be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman const Type *Ty, 3705be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman Value *V) { 3715be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman const Type *ElTy = PTy->getElementType(); 3725be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman SmallVector<Value *, 4> GepIndices; 3730bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman SmallVector<const SCEV *, 8> Ops(op_begin, op_end); 3745be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman bool AnyNonZeroIndices = false; 3755be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 376c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Split AddRecs up into parts as either of the parts may be usable 377c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // without the other. 378c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SplitAddRecs(Ops, Ty, SE); 379c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 380eb35699e642f2c021f04154bdb4bd90a1afb3baaBob Wilson // Descend down the pointer's type and attempt to convert the other 3815be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // operands into GEP indices, at each level. The first index in a GEP 3825be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // indexes into the array implied by the pointer operand; the rest of 3835be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // the indices index into the element or field type selected by the 3845be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // preceding index. 3855be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman for (;;) { 386c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If the scale size is not 0, attempt to factor out a scale for 387c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // array indexing. 3880bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman SmallVector<const SCEV *, 8> ScaledOps; 389150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman if (ElTy->isSized()) { 3904f8eea82d8967cffa85b9df6c9255717b059009eDan Gohman const SCEV *ElSize = SE.getSizeOfExpr(ElTy); 391150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman if (!ElSize->isZero()) { 392150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman SmallVector<const SCEV *, 8> NewOps; 393150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman for (unsigned i = 0, e = Ops.size(); i != e; ++i) { 394150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman const SCEV *Op = Ops[i]; 395150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman const SCEV *Remainder = SE.getIntegerSCEV(0, Ty); 396150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman if (FactorOutConstant(Op, Remainder, ElSize, SE, SE.TD)) { 397150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman // Op now has ElSize factored out. 398150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman ScaledOps.push_back(Op); 399150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman if (!Remainder->isZero()) 400150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman NewOps.push_back(Remainder); 401150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman AnyNonZeroIndices = true; 402150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman } else { 403150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman // The operand was not divisible, so add it to the list of operands 404150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman // we'll scan next iteration. 405150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman NewOps.push_back(Ops[i]); 406150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman } 407150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman } 408150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman // If we made any changes, update Ops. 409150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman if (!ScaledOps.empty()) { 410150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman Ops = NewOps; 411150dfa87113e51881c75676edd8e3549eb702d99Dan Gohman SimplifyAddOperands(Ops, Ty, SE); 4125be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 413c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 4145be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 415c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 416c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Record the scaled array index for this level of the type. If 417c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // we didn't find any operands that could be factored, tentatively 418c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // assume that element zero was selected (since the zero offset 419c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // would obviously be folded away). 4205be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman Value *Scaled = ScaledOps.empty() ? 421a7235ea7245028a0723e8ab7fd011386b3900777Owen Anderson Constant::getNullValue(Ty) : 4225be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman expandCodeFor(SE.getAddExpr(ScaledOps), Ty); 4235be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman GepIndices.push_back(Scaled); 4245be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 4255be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // Collect struct field index operands. 426c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman while (const StructType *STy = dyn_cast<StructType>(ElTy)) { 427c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman bool FoundFieldNo = false; 428c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // An empty struct has no fields. 429c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (STy->getNumElements() == 0) break; 430c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (SE.TD) { 431c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // With TargetData, field offsets are known. See if a constant offset 432c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // falls within any of the struct fields. 433c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (Ops.empty()) break; 4345be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (const SCEVConstant *C = dyn_cast<SCEVConstant>(Ops[0])) 4355be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (SE.getTypeSizeInBits(C->getType()) <= 64) { 4365be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman const StructLayout &SL = *SE.TD->getStructLayout(STy); 4375be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman uint64_t FullOffset = C->getValue()->getZExtValue(); 4385be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (FullOffset < SL.getSizeInBytes()) { 4395be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman unsigned ElIdx = SL.getElementContainingOffset(FullOffset); 4401d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson GepIndices.push_back( 4411d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson ConstantInt::get(Type::getInt32Ty(Ty->getContext()), ElIdx)); 4425be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman ElTy = STy->getTypeAtIndex(ElIdx); 4435be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman Ops[0] = 4446de29f8d960505421d61c80cdb738e16720b6c0eDan Gohman SE.getConstant(Ty, FullOffset - SL.getElementOffset(ElIdx)); 4455be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman AnyNonZeroIndices = true; 446c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FoundFieldNo = true; 4475be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 4485be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 449c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } else { 4500f5efe56258f8cd6ceff4d7955a5d80144cd9cb0Dan Gohman // Without TargetData, just check for an offsetof expression of the 451c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // appropriate struct type. 452c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = 0, e = Ops.size(); i != e; ++i) 4530f5efe56258f8cd6ceff4d7955a5d80144cd9cb0Dan Gohman if (const SCEVUnknown *U = dyn_cast<SCEVUnknown>(Ops[i])) { 4544f8eea82d8967cffa85b9df6c9255717b059009eDan Gohman const Type *CTy; 4550f5efe56258f8cd6ceff4d7955a5d80144cd9cb0Dan Gohman Constant *FieldNo; 4564f8eea82d8967cffa85b9df6c9255717b059009eDan Gohman if (U->isOffsetOf(CTy, FieldNo) && CTy == STy) { 4570f5efe56258f8cd6ceff4d7955a5d80144cd9cb0Dan Gohman GepIndices.push_back(FieldNo); 4580f5efe56258f8cd6ceff4d7955a5d80144cd9cb0Dan Gohman ElTy = 4590f5efe56258f8cd6ceff4d7955a5d80144cd9cb0Dan Gohman STy->getTypeAtIndex(cast<ConstantInt>(FieldNo)->getZExtValue()); 460c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops[i] = SE.getConstant(Ty, 0); 461c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman AnyNonZeroIndices = true; 462c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FoundFieldNo = true; 463c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman break; 464c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 4650f5efe56258f8cd6ceff4d7955a5d80144cd9cb0Dan Gohman } 4665be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 467c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If no struct field offsets were found, tentatively assume that 468c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // field zero was selected (since the zero offset would obviously 469c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // be folded away). 470c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!FoundFieldNo) { 471c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ElTy = STy->getTypeAtIndex(0u); 472c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman GepIndices.push_back( 473c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Constant::getNullValue(Type::getInt32Ty(Ty->getContext()))); 474c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 475c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 4765be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 477c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const ArrayType *ATy = dyn_cast<ArrayType>(ElTy)) 4785be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman ElTy = ATy->getElementType(); 479c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman else 480c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman break; 4815be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 4825be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 4833f46a3abeedba8d517b4182de34c821d752db058Dan Gohman // If none of the operands were convertible to proper GEP indices, cast 4845be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // the base to i8* and do an ugly getelementptr with that. It's still 4855be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // better than ptrtoint+arithmetic+inttoptr at least. 4865be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (!AnyNonZeroIndices) { 487c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Cast the base to i8*. 4885be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman V = InsertNoopCastOfTo(V, 489ac53a0b272452013124bfc70480aea5e41b60f40Duncan Sands Type::getInt8PtrTy(Ty->getContext(), PTy->getAddressSpace())); 490c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 491c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Expand the operands for a plain byte offset. 49292fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *Idx = expandCodeFor(SE.getAddExpr(Ops), Ty); 4935be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 4945be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // Fold a GEP with constant operands. 4955be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (Constant *CLHS = dyn_cast<Constant>(V)) 4965be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (Constant *CRHS = dyn_cast<Constant>(Idx)) 497baf3c404409d5e47b13984a7f95bfbd6d1f2e79eOwen Anderson return ConstantExpr::getGetElementPtr(CLHS, &CRHS, 1); 4985be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 4995be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // Do a quick scan to see if we have this GEP nearby. If so, reuse it. 5005be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman unsigned ScanLimit = 6; 501267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator BlockBegin = Builder.GetInsertBlock()->begin(); 502267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman // Scanning starts from the last instruction before the insertion point. 503267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator IP = Builder.GetInsertPoint(); 504267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (IP != BlockBegin) { 5055be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman --IP; 5065be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman for (; ScanLimit; --IP, --ScanLimit) { 5078d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen // Don't count dbg.value against the ScanLimit, to avoid perturbing the 5088d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen // generated code. 5098d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen if (isa<DbgInfoIntrinsic>(IP)) 5108d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen ScanLimit++; 5115be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (IP->getOpcode() == Instruction::GetElementPtr && 5125be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman IP->getOperand(0) == V && IP->getOperand(1) == Idx) 5135be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return IP; 5145be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (IP == BlockBegin) break; 5155be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 5165be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 5175be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 518087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Save the original insertion point so we can restore it when we're done. 519087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 520087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 521087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 522087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Move the insertion point out of as many loops as we can. 523087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman while (const Loop *L = SE.LI->getLoopFor(Builder.GetInsertBlock())) { 524087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!L->isLoopInvariant(V) || !L->isLoopInvariant(Idx)) break; 525087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock *Preheader = L->getLoopPreheader(); 526087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!Preheader) break; 527087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 528087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Ok, move up a level. 529087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Builder.SetInsertPoint(Preheader, Preheader->getTerminator()); 530087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } 531087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 532c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Emit a GEP. 533c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Value *GEP = Builder.CreateGEP(V, Idx, "uglygep"); 534a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(GEP); 535087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 536087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Restore the original insert point. 537087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (SaveInsertBB) 538087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 539087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 5405be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return GEP; 5415be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 5425be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 543087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Save the original insertion point so we can restore it when we're done. 544087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 545087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 546087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 547087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Move the insertion point out of as many loops as we can. 548087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman while (const Loop *L = SE.LI->getLoopFor(Builder.GetInsertBlock())) { 549087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!L->isLoopInvariant(V)) break; 550087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 551087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman bool AnyIndexNotLoopInvariant = false; 552087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (SmallVectorImpl<Value *>::const_iterator I = GepIndices.begin(), 553087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman E = GepIndices.end(); I != E; ++I) 554087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!L->isLoopInvariant(*I)) { 555087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman AnyIndexNotLoopInvariant = true; 556087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman break; 557087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } 558087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (AnyIndexNotLoopInvariant) 559087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman break; 560087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 561087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock *Preheader = L->getLoopPreheader(); 562087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!Preheader) break; 563087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 564087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Ok, move up a level. 565087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Builder.SetInsertPoint(Preheader, Preheader->getTerminator()); 566087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } 567087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 568d6aa02de1076c801ac41295156a2379637976918Dan Gohman // Insert a pretty getelementptr. Note that this GEP is not marked inbounds, 569d6aa02de1076c801ac41295156a2379637976918Dan Gohman // because ScalarEvolution may have changed the address arithmetic to 570d6aa02de1076c801ac41295156a2379637976918Dan Gohman // compute a value which is beyond the end of the allocated object. 571a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *Casted = V; 572a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (V->getType() != PTy) 573a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Casted = InsertNoopCastOfTo(Casted, PTy); 574a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *GEP = Builder.CreateGEP(Casted, 575267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman GepIndices.begin(), 576267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman GepIndices.end(), 577267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman "scevgep"); 5785be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman Ops.push_back(SE.getUnknown(GEP)); 579a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(GEP); 580087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 581087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Restore the original insert point. 582087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (SaveInsertBB) 583087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 584087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 5855be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return expand(SE.getAddExpr(Ops)); 5865be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman} 5875be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 588a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman/// isNonConstantNegative - Return true if the specified scev is negated, but 589a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman/// not a constant. 590a10756ee657a4d43a48cca5c166919093930ed6bDan Gohmanstatic bool isNonConstantNegative(const SCEV *F) { 591a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEVMulExpr *Mul = dyn_cast<SCEVMulExpr>(F); 592a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!Mul) return false; 593a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 594a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // If there is a constant factor, it will be first. 595a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEVConstant *SC = dyn_cast<SCEVConstant>(Mul->getOperand(0)); 596a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!SC) return false; 597a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 598a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Return true if the value is negative, this matches things like (-42 * V). 599a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman return SC->getValue()->getValue().isNegative(); 600a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman} 601a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 602087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman/// PickMostRelevantLoop - Given two loops pick the one that's most relevant for 603087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman/// SCEV expansion. If they are nested, this is the most nested. If they are 604087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman/// neighboring, pick the later. 605087bd1e3a12893873761736bf0f905a350e9e708Dan Gohmanstatic const Loop *PickMostRelevantLoop(const Loop *A, const Loop *B, 606087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman DominatorTree &DT) { 607087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!A) return B; 608087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!B) return A; 609087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (A->contains(B)) return B; 610087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (B->contains(A)) return A; 611087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (DT.dominates(A->getHeader(), B->getHeader())) return B; 612087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (DT.dominates(B->getHeader(), A->getHeader())) return A; 613087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return A; // Arbitrarily break the tie. 614087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman} 615087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 616087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman/// GetRelevantLoop - Get the most relevant loop associated with the given 617087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman/// expression, according to PickMostRelevantLoop. 618087bd1e3a12893873761736bf0f905a350e9e708Dan Gohmanstatic const Loop *GetRelevantLoop(const SCEV *S, LoopInfo &LI, 619087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman DominatorTree &DT) { 620087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (isa<SCEVConstant>(S)) 621087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return 0; 622087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (const SCEVUnknown *U = dyn_cast<SCEVUnknown>(S)) { 623087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (const Instruction *I = dyn_cast<Instruction>(U->getValue())) 624087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return LI.getLoopFor(I->getParent()); 625087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return 0; 626087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } 627087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (const SCEVNAryExpr *N = dyn_cast<SCEVNAryExpr>(S)) { 628087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman const Loop *L = 0; 629087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(S)) 630087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman L = AR->getLoop(); 631087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (SCEVNAryExpr::op_iterator I = N->op_begin(), E = N->op_end(); 632087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman I != E; ++I) 633087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman L = PickMostRelevantLoop(L, GetRelevantLoop(*I, LI, DT), DT); 634087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return L; 635087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } 636087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (const SCEVCastExpr *C = dyn_cast<SCEVCastExpr>(S)) 637087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return GetRelevantLoop(C->getOperand(), LI, DT); 638087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (const SCEVUDivExpr *D = dyn_cast<SCEVUDivExpr>(S)) 639087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return PickMostRelevantLoop(GetRelevantLoop(D->getLHS(), LI, DT), 640087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman GetRelevantLoop(D->getRHS(), LI, DT), 641087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman DT); 642087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman llvm_unreachable("Unexpected SCEV type!"); 643087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman} 644c4f7ec85ecb760fff2b702c6deb06506b968ba4fDan Gohman 645087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman/// LoopCompare - Compare loops by PickMostRelevantLoop. 646087bd1e3a12893873761736bf0f905a350e9e708Dan Gohmanclass LoopCompare { 647087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman DominatorTree &DT; 648087bd1e3a12893873761736bf0f905a350e9e708Dan Gohmanpublic: 649087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman explicit LoopCompare(DominatorTree &dt) : DT(dt) {} 650087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 651087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman bool operator()(std::pair<const Loop *, const SCEV *> LHS, 652087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman std::pair<const Loop *, const SCEV *> RHS) const { 653087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Compare loops with PickMostRelevantLoop. 654087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (LHS.first != RHS.first) 655087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return PickMostRelevantLoop(LHS.first, RHS.first, DT) != LHS.first; 656087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 657087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // If one operand is a non-constant negative and the other is not, 658087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // put the non-constant negative on the right so that a sub can 659087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // be used instead of a negate and add. 660087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (isNonConstantNegative(LHS.second)) { 661087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!isNonConstantNegative(RHS.second)) 662087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return false; 663087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } else if (isNonConstantNegative(RHS.second)) 664087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return true; 665087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 666087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Otherwise they are equivalent according to this comparison. 667087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return false; 668c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 669087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman}; 6705be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 671087bd1e3a12893873761736bf0f905a350e9e708Dan GohmanValue *SCEVExpander::visitAddExpr(const SCEVAddExpr *S) { 672087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 673e24fa64d52330626553298f56ba5aa702624c282Dan Gohman 674087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Collect all the add operands in a loop, along with their associated loops. 675087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Iterate in reverse so that constants are emitted last, all else equal, and 676087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // so that pointer operands are inserted first, which the code below relies on 677087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // to form more involved GEPs. 678087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman SmallVector<std::pair<const Loop *, const SCEV *>, 8> OpsAndLoops; 679087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (std::reverse_iterator<SCEVAddExpr::op_iterator> I(S->op_end()), 680087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman E(S->op_begin()); I != E; ++I) 681087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman OpsAndLoops.push_back(std::make_pair(GetRelevantLoop(*I, *SE.LI, *SE.DT), 682087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman *I)); 683087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 684087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Sort by loop. Use a stable sort so that constants follow non-constants and 685087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // pointer operands precede non-pointer operands. 686087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman std::stable_sort(OpsAndLoops.begin(), OpsAndLoops.end(), LoopCompare(*SE.DT)); 687087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 688087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Emit instructions to add all the operands. Hoist as much as possible 689087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // out of loops, and form meaningful getelementptrs where possible. 690087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Value *Sum = 0; 691087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (SmallVectorImpl<std::pair<const Loop *, const SCEV *> >::iterator 692087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman I = OpsAndLoops.begin(), E = OpsAndLoops.end(); I != E; ) { 693087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman const Loop *CurLoop = I->first; 694087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman const SCEV *Op = I->second; 695087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!Sum) { 696087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // This is the first operand. Just expand it. 697087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = expand(Op); 698087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 699087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } else if (const PointerType *PTy = dyn_cast<PointerType>(Sum->getType())) { 700087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // The running sum expression is a pointer. Try to form a getelementptr 701087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // at this level with that as the base. 702087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman SmallVector<const SCEV *, 4> NewOps; 703087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (; I != E && I->first == CurLoop; ++I) 704087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman NewOps.push_back(I->second); 705087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = expandAddToGEP(NewOps.begin(), NewOps.end(), PTy, Ty, Sum); 706087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } else if (const PointerType *PTy = dyn_cast<PointerType>(Op->getType())) { 707087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // The running sum is an integer, and there's a pointer at this level. 708f8d0578e4cbd5922696c92f5068c5513d8e8d60eDan Gohman // Try to form a getelementptr. If the running sum is instructions, 709f8d0578e4cbd5922696c92f5068c5513d8e8d60eDan Gohman // use a SCEVUnknown to avoid re-analyzing them. 710087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman SmallVector<const SCEV *, 4> NewOps; 711f8d0578e4cbd5922696c92f5068c5513d8e8d60eDan Gohman NewOps.push_back(isa<Instruction>(Sum) ? SE.getUnknown(Sum) : 712f8d0578e4cbd5922696c92f5068c5513d8e8d60eDan Gohman SE.getSCEV(Sum)); 713087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (++I; I != E && I->first == CurLoop; ++I) 714087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman NewOps.push_back(I->second); 715087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = expandAddToGEP(NewOps.begin(), NewOps.end(), PTy, Ty, expand(Op)); 716087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } else if (isNonConstantNegative(Op)) { 717087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Instead of doing a negate and add, just do a subtract. 718a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *W = expandCodeFor(SE.getNegativeSCEV(Op), Ty); 719087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = InsertNoopCastOfTo(Sum, Ty); 720087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = InsertBinop(Instruction::Sub, Sum, W); 721087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 722a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } else { 723087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // A simple add. 724a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *W = expandCodeFor(Op, Ty); 725087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = InsertNoopCastOfTo(Sum, Ty); 726087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Canonicalize a constant to the RHS. 727087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (isa<Constant>(Sum)) std::swap(Sum, W); 728087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = InsertBinop(Instruction::Add, Sum, W); 729087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 730a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 7312d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman } 732087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 733087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return Sum; 734e24fa64d52330626553298f56ba5aa702624c282Dan Gohman} 7355be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 736890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitMulExpr(const SCEVMulExpr *S) { 737af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 738087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 739087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Collect all the mul operands in a loop, along with their associated loops. 740087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Iterate in reverse so that constants are emitted last, all else equal. 741087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman SmallVector<std::pair<const Loop *, const SCEV *>, 8> OpsAndLoops; 742087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (std::reverse_iterator<SCEVMulExpr::op_iterator> I(S->op_end()), 743087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman E(S->op_begin()); I != E; ++I) 744087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman OpsAndLoops.push_back(std::make_pair(GetRelevantLoop(*I, *SE.LI, *SE.DT), 745087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman *I)); 746087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 747087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Sort by loop. Use a stable sort so that constants follow non-constants. 748087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman std::stable_sort(OpsAndLoops.begin(), OpsAndLoops.end(), LoopCompare(*SE.DT)); 749087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 750087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Emit instructions to mul all the operands. Hoist as much as possible 751087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // out of loops. 752087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Value *Prod = 0; 753087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (SmallVectorImpl<std::pair<const Loop *, const SCEV *> >::iterator 754087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman I = OpsAndLoops.begin(), E = OpsAndLoops.end(); I != E; ) { 755087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman const SCEV *Op = I->second; 756087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!Prod) { 757087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // This is the first operand. Just expand it. 758087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Prod = expand(Op); 759087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 760087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } else if (Op->isAllOnesValue()) { 761087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Instead of doing a multiply by negative one, just do a negate. 762087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Prod = InsertNoopCastOfTo(Prod, Ty); 763087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Prod = InsertBinop(Instruction::Sub, Constant::getNullValue(Ty), Prod); 764087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 765087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } else { 766087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // A simple mul. 767087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Value *W = expandCodeFor(Op, Ty); 768087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Prod = InsertNoopCastOfTo(Prod, Ty); 769087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Canonicalize a constant to the RHS. 770087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (isa<Constant>(Prod)) std::swap(Prod, W); 771087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Prod = InsertBinop(Instruction::Mul, Prod, W); 772087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 773087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } 7742d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman } 7752d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman 776087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return Prod; 77736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman} 77836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 779890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitUDivExpr(const SCEVUDivExpr *S) { 780af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 7812d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman 78292fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *LHS = expandCodeFor(S->getLHS(), Ty); 783890f92b744fb074465bc2b7006ee753a181f62a4Dan Gohman if (const SCEVConstant *SC = dyn_cast<SCEVConstant>(S->getRHS())) { 7846177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky const APInt &RHS = SC->getValue()->getValue(); 7856177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky if (RHS.isPowerOf2()) 7866177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky return InsertBinop(Instruction::LShr, LHS, 787eed707b1e6097aac2bb6b3d47271f6300ace7f2eOwen Anderson ConstantInt::get(Ty, RHS.logBase2())); 7886177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky } 7896177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky 79092fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *RHS = expandCodeFor(S->getRHS(), Ty); 791267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman return InsertBinop(Instruction::UDiv, LHS, RHS); 7926177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky} 7936177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky 794453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// Move parts of Base into Rest to leave Base with the minimal 795453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// expression that provides a pointer operand suitable for a 796453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// GEP expansion. 7970bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohmanstatic void ExposePointerBase(const SCEV *&Base, const SCEV *&Rest, 798453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman ScalarEvolution &SE) { 799453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman while (const SCEVAddRecExpr *A = dyn_cast<SCEVAddRecExpr>(Base)) { 800453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Base = A->getStart(); 801453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Rest = SE.getAddExpr(Rest, 802453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman SE.getAddRecExpr(SE.getIntegerSCEV(0, A->getType()), 803453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman A->getStepRecurrence(SE), 804453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman A->getLoop())); 805453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 806453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman if (const SCEVAddExpr *A = dyn_cast<SCEVAddExpr>(Base)) { 807453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Base = A->getOperand(A->getNumOperands()-1); 8080bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman SmallVector<const SCEV *, 8> NewAddOps(A->op_begin(), A->op_end()); 809453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman NewAddOps.back() = Rest; 810453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Rest = SE.getAddExpr(NewAddOps); 811453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman ExposePointerBase(Base, Rest, SE); 812453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 813453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman} 814453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 815a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman/// getAddRecExprPHILiterally - Helper for expandAddRecExprLiterally. Expand 816a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman/// the base addrec, which is the addrec without any non-loop-dominating 817a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman/// values, and return the PHI. 818a10756ee657a4d43a48cca5c166919093930ed6bDan GohmanPHINode * 819a10756ee657a4d43a48cca5c166919093930ed6bDan GohmanSCEVExpander::getAddRecExprPHILiterally(const SCEVAddRecExpr *Normalized, 820a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const Loop *L, 821a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const Type *ExpandTy, 822a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const Type *IntTy) { 823a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Reuse a previously-inserted PHI, if present. 824a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman for (BasicBlock::iterator I = L->getHeader()->begin(); 825a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PHINode *PN = dyn_cast<PHINode>(I); ++I) 826572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman if (SE.isSCEVable(PN->getType()) && 827572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman (SE.getEffectiveSCEVType(PN->getType()) == 828572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman SE.getEffectiveSCEVType(Normalized->getType())) && 829572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman SE.getSCEV(PN) == Normalized) 830572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman if (BasicBlock *LatchBlock = L->getLoopLatch()) { 831572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman Instruction *IncV = 83222e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman cast<Instruction>(PN->getIncomingValueForBlock(LatchBlock)); 83322e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman 83422e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // Determine if this is a well-behaved chain of instructions leading 83522e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // back to the PHI. It probably will be, if we're scanning an inner 83622e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // loop already visited by LSR for example, but it wouldn't have 83722e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // to be. 83822e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman do { 83922e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman if (IncV->getNumOperands() == 0 || isa<PHINode>(IncV)) { 84022e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV = 0; 84122e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman break; 84222e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman } 8439feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman // If any of the operands don't dominate the insert position, bail. 8449feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman // Addrec operands are always loop-invariant, so this can only happen 8459feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman // if there are instructions which haven't been hoisted. 8469feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman for (User::op_iterator OI = IncV->op_begin()+1, 8479feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman OE = IncV->op_end(); OI != OE; ++OI) 8489feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman if (Instruction *OInst = dyn_cast<Instruction>(OI)) 8499feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman if (!SE.DT->dominates(OInst, IVIncInsertPos)) { 8509feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman IncV = 0; 8519feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman break; 8529feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman } 8539feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman if (!IncV) 8549feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman break; 8559feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman // Advance to the next instruction. 85622e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV = dyn_cast<Instruction>(IncV->getOperand(0)); 85722e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman if (!IncV) 85822e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman break; 85922e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman if (IncV->mayHaveSideEffects()) { 86022e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV = 0; 86122e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman break; 86222e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman } 86322e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman } while (IncV != PN); 86422e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman 86522e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman if (IncV) { 86622e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // Ok, the add recurrence looks usable. 86722e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // Remember this PHI, even in post-inc mode. 86822e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman InsertedValues.insert(PN); 86922e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // Remember the increment. 87022e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV = cast<Instruction>(PN->getIncomingValueForBlock(LatchBlock)); 87122e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman rememberInstruction(IncV); 87222e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman if (L == IVIncInsertLoop) 87322e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman do { 87422e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman if (SE.DT->dominates(IncV, IVIncInsertPos)) 87522e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman break; 87622e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // Make sure the increment is where we want it. But don't move it 87722e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // down past a potential existing post-inc user. 87822e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV->moveBefore(IVIncInsertPos); 87922e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IVIncInsertPos = IncV; 88022e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV = cast<Instruction>(IncV->getOperand(0)); 88122e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman } while (IncV != PN); 88222e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman return PN; 88322e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman } 884572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman } 885a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 886a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Save the original insertion point so we can restore it when we're done. 887a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 888a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 889a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 890a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Expand code for the start value. 891a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *StartV = expandCodeFor(Normalized->getStart(), ExpandTy, 892a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman L->getHeader()->begin()); 893a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 894a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Expand code for the step value. Insert instructions right before the 895a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // terminator corresponding to the back-edge. Do this before creating the PHI 896a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // so that PHI reuse code doesn't see an incomplete PHI. If the stride is 897a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // negative, insert a sub instead of an add for the increment (unless it's a 898a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // constant, because subtracts of constants are canonicalized to adds). 899a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *Step = Normalized->getStepRecurrence(SE); 9001df9859c40492511b8aa4321eb76496005d3b75bDuncan Sands bool isPointer = ExpandTy->isPointerTy(); 901a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman bool isNegative = !isPointer && isNonConstantNegative(Step); 902a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (isNegative) 903a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Step = SE.getNegativeSCEV(Step); 904a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *StepV = expandCodeFor(Step, IntTy, L->getHeader()->begin()); 905a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 906a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Create the PHI. 907a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Builder.SetInsertPoint(L->getHeader(), L->getHeader()->begin()); 908a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PHINode *PN = Builder.CreatePHI(ExpandTy, "lsr.iv"); 909a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(PN); 910a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 911a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Create the step instructions and populate the PHI. 912a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman BasicBlock *Header = L->getHeader(); 913a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman for (pred_iterator HPI = pred_begin(Header), HPE = pred_end(Header); 914a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman HPI != HPE; ++HPI) { 915a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman BasicBlock *Pred = *HPI; 916a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 917a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Add a start value. 918a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!L->contains(Pred)) { 919a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PN->addIncoming(StartV, Pred); 920a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman continue; 921a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 922a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 923a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Create a step value and add it to the PHI. If IVIncInsertLoop is 924a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // non-null and equal to the addrec's loop, insert the instructions 925a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // at IVIncInsertPos. 926a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Instruction *InsertPos = L == IVIncInsertLoop ? 927a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman IVIncInsertPos : Pred->getTerminator(); 928a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Builder.SetInsertPoint(InsertPos->getParent(), InsertPos); 929a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *IncV; 930a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // If the PHI is a pointer, use a GEP, otherwise use an add or sub. 931a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (isPointer) { 932a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const PointerType *GEPPtrTy = cast<PointerType>(ExpandTy); 933a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // If the step isn't constant, don't use an implicitly scaled GEP, because 934a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // that would require a multiply inside the loop. 935a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!isa<ConstantInt>(StepV)) 936a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman GEPPtrTy = PointerType::get(Type::getInt1Ty(SE.getContext()), 937a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman GEPPtrTy->getAddressSpace()); 938a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *const StepArray[1] = { SE.getSCEV(StepV) }; 939a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman IncV = expandAddToGEP(StepArray, StepArray+1, GEPPtrTy, IntTy, PN); 940a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (IncV->getType() != PN->getType()) { 941a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman IncV = Builder.CreateBitCast(IncV, PN->getType(), "tmp"); 942a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(IncV); 943a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 944a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } else { 945a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman IncV = isNegative ? 946a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Builder.CreateSub(PN, StepV, "lsr.iv.next") : 947a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Builder.CreateAdd(PN, StepV, "lsr.iv.next"); 948a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(IncV); 949a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 950a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PN->addIncoming(IncV, Pred); 951a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 952a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 953a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Restore the original insert point. 954a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (SaveInsertBB) 955455985501381777db03534c925a35e261e356395Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 956a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 957a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Remember this PHI, even in post-inc mode. 958a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman InsertedValues.insert(PN); 959a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 960a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman return PN; 961a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman} 962a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 963a10756ee657a4d43a48cca5c166919093930ed6bDan GohmanValue *SCEVExpander::expandAddRecExprLiterally(const SCEVAddRecExpr *S) { 964a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const Type *STy = S->getType(); 965a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const Type *IntTy = SE.getEffectiveSCEVType(STy); 966a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const Loop *L = S->getLoop(); 967a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 968a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Determine a normalized form of this expression, which is the expression 969a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // before any post-inc adjustment is made. 970a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEVAddRecExpr *Normalized = S; 971448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman if (PostIncLoops.count(L)) { 972448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman PostIncLoopSet Loops; 973448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman Loops.insert(L); 974448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman Normalized = 975448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman cast<SCEVAddRecExpr>(TransformForPostIncUse(Normalize, S, 0, 0, 976448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman Loops, SE, *SE.DT)); 977a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 978a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 979a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Strip off any non-loop-dominating component from the addrec start. 980a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *Start = Normalized->getStart(); 981a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *PostLoopOffset = 0; 982a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!Start->properlyDominates(L->getHeader(), SE.DT)) { 983a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PostLoopOffset = Start; 984a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Start = SE.getIntegerSCEV(0, Normalized->getType()); 985a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Normalized = 986a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman cast<SCEVAddRecExpr>(SE.getAddRecExpr(Start, 987a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Normalized->getStepRecurrence(SE), 988a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Normalized->getLoop())); 989a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 990a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 991a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Strip off any non-loop-dominating component from the addrec step. 992a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *Step = Normalized->getStepRecurrence(SE); 993a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *PostLoopScale = 0; 994a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!Step->hasComputableLoopEvolution(L) && 995a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman !Step->dominates(L->getHeader(), SE.DT)) { 996a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PostLoopScale = Step; 997a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Step = SE.getIntegerSCEV(1, Normalized->getType()); 998a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Normalized = 999a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman cast<SCEVAddRecExpr>(SE.getAddRecExpr(Start, Step, 1000a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Normalized->getLoop())); 1001a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1002a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1003a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Expand the core addrec. If we need post-loop scaling, force it to 1004a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // expand to an integer type to avoid the need for additional casting. 1005a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const Type *ExpandTy = PostLoopScale ? IntTy : STy; 1006a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PHINode *PN = getAddRecExprPHILiterally(Normalized, L, ExpandTy, IntTy); 1007a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 10083f46a3abeedba8d517b4182de34c821d752db058Dan Gohman // Accommodate post-inc mode, if necessary. 1009a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *Result; 1010448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman if (!PostIncLoops.count(L)) 1011a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Result = PN; 1012a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman else { 1013a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // In PostInc mode, use the post-incremented value. 1014a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman BasicBlock *LatchBlock = L->getLoopLatch(); 1015a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman assert(LatchBlock && "PostInc mode requires a unique loop latch!"); 1016a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Result = PN->getIncomingValueForBlock(LatchBlock); 1017a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1018a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1019a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Re-apply any non-loop-dominating scale. 1020a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (PostLoopScale) { 10210a799ab15801d4ebf68eeb151d6375a799c87d9aDan Gohman Result = InsertNoopCastOfTo(Result, IntTy); 1022a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Result = Builder.CreateMul(Result, 1023a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman expandCodeFor(PostLoopScale, IntTy)); 1024a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(Result); 1025a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1026a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1027a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Re-apply any non-loop-dominating offset. 1028a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (PostLoopOffset) { 1029a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (const PointerType *PTy = dyn_cast<PointerType>(ExpandTy)) { 1030a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *const OffsetArray[1] = { PostLoopOffset }; 1031a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Result = expandAddToGEP(OffsetArray, OffsetArray+1, PTy, IntTy, Result); 1032a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } else { 10330a799ab15801d4ebf68eeb151d6375a799c87d9aDan Gohman Result = InsertNoopCastOfTo(Result, IntTy); 1034a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Result = Builder.CreateAdd(Result, 1035a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman expandCodeFor(PostLoopOffset, IntTy)); 1036a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(Result); 1037a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1038a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1039a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1040a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman return Result; 1041a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman} 1042a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1043890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitAddRecExpr(const SCEVAddRecExpr *S) { 1044a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!CanonicalMode) return expandAddRecExprLiterally(S); 1045a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1046af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 104736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman const Loop *L = S->getLoop(); 104836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 10494d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // First check for an existing canonical IV in a suitable type. 10504d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman PHINode *CanonicalIV = 0; 10514d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (PHINode *PN = L->getCanonicalInductionVariable()) 10524d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (SE.isSCEVable(PN->getType()) && 10531df9859c40492511b8aa4321eb76496005d3b75bDuncan Sands SE.getEffectiveSCEVType(PN->getType())->isIntegerTy() && 10544d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman SE.getTypeSizeInBits(PN->getType()) >= SE.getTypeSizeInBits(Ty)) 10554d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman CanonicalIV = PN; 10564d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman 10574d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // Rewrite an AddRec in terms of the canonical induction variable, if 10584d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // its type is more narrow. 10594d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (CanonicalIV && 10604d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman SE.getTypeSizeInBits(CanonicalIV->getType()) > 10614d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman SE.getTypeSizeInBits(Ty)) { 1062f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman SmallVector<const SCEV *, 4> NewOps(S->getNumOperands()); 1063f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman for (unsigned i = 0, e = S->getNumOperands(); i != e; ++i) 1064f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman NewOps[i] = SE.getAnyExtendExpr(S->op_begin()[i], CanonicalIV->getType()); 1065f3f1be6f065d1b90afe80ca80c9d6473c10deb5aDan Gohman Value *V = expand(SE.getAddRecExpr(NewOps, S->getLoop())); 1066267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 1067267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 10684d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman BasicBlock::iterator NewInsertPt = 10697896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner llvm::next(BasicBlock::iterator(cast<Instruction>(V))); 10704d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman while (isa<PHINode>(NewInsertPt)) ++NewInsertPt; 10714d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman V = expandCodeFor(SE.getTruncateExpr(SE.getUnknown(V), Ty), 0, 10724d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman NewInsertPt); 1073455985501381777db03534c925a35e261e356395Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 10744d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman return V; 10754d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman } 10764d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman 107736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // {X,+,F} --> X + {0,+,F} 1078cfeb6a450632f2a6cd05302633c8c2b8c90cfdfdDan Gohman if (!S->getStart()->isZero()) { 1079f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman SmallVector<const SCEV *, 4> NewOps(S->op_begin(), S->op_end()); 1080246b2564d3bbbafe06ebf6a67745cd24141b5cb4Dan Gohman NewOps[0] = SE.getIntegerSCEV(0, Ty); 10810bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *Rest = SE.getAddRecExpr(NewOps, L); 1082453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 1083453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // Turn things like ptrtoint+arithmetic+inttoptr into GEP. See the 1084453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // comments on expandAddToGEP for details. 1085c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Base = S->getStart(); 1086c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *RestArray[1] = { Rest }; 1087c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Dig into the expression to find the pointer base for a GEP. 1088c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ExposePointerBase(Base, RestArray[0], SE); 1089c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If we found a pointer, expand the AddRec with a GEP. 1090c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const PointerType *PTy = dyn_cast<PointerType>(Base->getType())) { 1091c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Make sure the Base isn't something exotic, such as a multiplied 1092c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // or divided pointer value. In those cases, the result type isn't 1093c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // actually a pointer type. 1094c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!isa<SCEVMulExpr>(Base) && !isa<SCEVUDivExpr>(Base)) { 1095c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Value *StartV = expand(Base); 1096c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman assert(StartV->getType() == PTy && "Pointer type mismatch for GEP!"); 1097c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return expandAddToGEP(RestArray, RestArray+1, PTy, Ty, StartV); 1098453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 1099453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 1100453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 110140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // Just do a normal add. Pre-expand the operands to suppress folding. 110240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return expand(SE.getAddExpr(SE.getUnknown(expand(S->getStart())), 110340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman SE.getUnknown(expand(Rest)))); 110436f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman } 110536f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 110636f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // {0,+,1} --> Insert a canonical induction variable into the loop! 110717f1972c770dc18f5c7c3c95776b4d62ae9e121dDan Gohman if (S->isAffine() && 1108246b2564d3bbbafe06ebf6a67745cd24141b5cb4Dan Gohman S->getOperand(1) == SE.getIntegerSCEV(1, Ty)) { 11094d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // If there's a canonical IV, just use it. 11104d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (CanonicalIV) { 11114d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman assert(Ty == SE.getEffectiveSCEVType(CanonicalIV->getType()) && 11124d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman "IVs with types different from the canonical IV should " 11134d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman "already have been handled!"); 11144d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman return CanonicalIV; 11154d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman } 11164d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman 111736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // Create and insert the PHI node for the induction variable in the 111836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // specified loop. 111936f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman BasicBlock *Header = L->getHeader(); 1120051a950000e21935165db56695e35bade668193bGabor Greif PHINode *PN = PHINode::Create(Ty, "indvar", Header->begin()); 1121a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(PN); 112236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 1123eed707b1e6097aac2bb6b3d47271f6300ace7f2eOwen Anderson Constant *One = ConstantInt::get(Ty, 1); 112483d577490b1473213b6973236110c28e59127956Dan Gohman for (pred_iterator HPI = pred_begin(Header), HPE = pred_end(Header); 112583d577490b1473213b6973236110c28e59127956Dan Gohman HPI != HPE; ++HPI) 112683d577490b1473213b6973236110c28e59127956Dan Gohman if (L->contains(*HPI)) { 11273abf905b50f33340ae81913da81b0eda96fa4616Dan Gohman // Insert a unit add instruction right before the terminator 11283abf905b50f33340ae81913da81b0eda96fa4616Dan Gohman // corresponding to the back-edge. 112983d577490b1473213b6973236110c28e59127956Dan Gohman Instruction *Add = BinaryOperator::CreateAdd(PN, One, "indvar.next", 113083d577490b1473213b6973236110c28e59127956Dan Gohman (*HPI)->getTerminator()); 1131a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(Add); 113283d577490b1473213b6973236110c28e59127956Dan Gohman PN->addIncoming(Add, *HPI); 113383d577490b1473213b6973236110c28e59127956Dan Gohman } else { 113483d577490b1473213b6973236110c28e59127956Dan Gohman PN->addIncoming(Constant::getNullValue(Ty), *HPI); 113583d577490b1473213b6973236110c28e59127956Dan Gohman } 113636f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman } 113736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 11384d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // {0,+,F} --> {0,+,1} * F 113936f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // Get the canonical induction variable I for this loop. 11404d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman Value *I = CanonicalIV ? 11414d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman CanonicalIV : 11424d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman getOrInsertCanonicalInductionVariable(L, Ty); 114336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 1144df14a04b5ccbbe6a46c2ccb93e27b12a36ff163eChris Lattner // If this is a simple linear addrec, emit it now as a special case. 114540a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (S->isAffine()) // {0,+,F} --> i*F 114640a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return 114740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman expand(SE.getTruncateOrNoop( 114840a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman SE.getMulExpr(SE.getUnknown(I), 114940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman SE.getNoopOrAnyExtend(S->getOperand(1), 115040a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman I->getType())), 115140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman Ty)); 115236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 115336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // If this is a chain of recurrences, turn it into a closed form, using the 115436f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // folders, then expandCodeFor the closed form. This allows the folders to 115536f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // simplify the expression without having to build a bunch of special code 115636f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // into this folder. 11570bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *IH = SE.getUnknown(I); // Get I as a "symbolic" SCEV. 115836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 11594d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // Promote S up to the canonical IV type, if the cast is foldable. 11600bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *NewS = S; 11610bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *Ext = SE.getNoopOrAnyExtend(S, I->getType()); 11624d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (isa<SCEVAddRecExpr>(Ext)) 11634d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman NewS = Ext; 11644d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman 11650bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *V = cast<SCEVAddRecExpr>(NewS)->evaluateAtIteration(IH, SE); 1166e81561909d128c6e2d8033cb5465a49b2596b26aBill Wendling //cerr << "Evaluated: " << *this << "\n to: " << *V << "\n"; 116736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 11684d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // Truncate the result down to the original type, if needed. 11690bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *T = SE.getTruncateOrNoop(V, Ty); 1170469f3cdc13851914f3a766cbd8f701cf8431cacaDan Gohman return expand(T); 117136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman} 117296fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov 1173890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitTruncateExpr(const SCEVTruncateExpr *S) { 1174af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 117592fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *V = expandCodeFor(S->getOperand(), 117692fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman SE.getEffectiveSCEVType(S->getOperand()->getType())); 1177267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *I = Builder.CreateTrunc(V, Ty, "tmp"); 1178a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(I); 1179cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return I; 118011f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 118111f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 1182890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitZeroExtendExpr(const SCEVZeroExtendExpr *S) { 1183af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 118492fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *V = expandCodeFor(S->getOperand(), 118592fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman SE.getEffectiveSCEVType(S->getOperand()->getType())); 1186267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *I = Builder.CreateZExt(V, Ty, "tmp"); 1187a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(I); 1188cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return I; 118911f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 119011f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 1191890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitSignExtendExpr(const SCEVSignExtendExpr *S) { 1192af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 119392fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *V = expandCodeFor(S->getOperand(), 119492fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman SE.getEffectiveSCEVType(S->getOperand()->getType())); 1195267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *I = Builder.CreateSExt(V, Ty, "tmp"); 1196a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(I); 1197cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return I; 119811f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 119911f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 1200890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitSMaxExpr(const SCEVSMaxExpr *S) { 12010196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Value *LHS = expand(S->getOperand(S->getNumOperands()-1)); 12020196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman const Type *Ty = LHS->getType(); 12030196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman for (int i = S->getNumOperands()-2; i >= 0; --i) { 12040196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, do the 12050196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // rest of the comparisons as integer. 12060196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (S->getOperand(i)->getType() != Ty) { 12070196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Ty = SE.getEffectiveSCEVType(Ty); 12080196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, Ty); 12090196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman } 121092fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *RHS = expandCodeFor(S->getOperand(i), Ty); 1211267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *ICmp = Builder.CreateICmpSGT(LHS, RHS, "tmp"); 1212a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(ICmp); 1213267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *Sel = Builder.CreateSelect(ICmp, LHS, RHS, "smax"); 1214a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(Sel); 1215cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman LHS = Sel; 1216c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky } 12170196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, cast the 12180196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // final result back to the pointer type. 12190196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (LHS->getType() != S->getType()) 12200196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, S->getType()); 1221c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky return LHS; 1222c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky} 1223c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky 1224890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitUMaxExpr(const SCEVUMaxExpr *S) { 12250196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Value *LHS = expand(S->getOperand(S->getNumOperands()-1)); 12260196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman const Type *Ty = LHS->getType(); 12270196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman for (int i = S->getNumOperands()-2; i >= 0; --i) { 12280196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, do the 12290196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // rest of the comparisons as integer. 12300196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (S->getOperand(i)->getType() != Ty) { 12310196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Ty = SE.getEffectiveSCEVType(Ty); 12320196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, Ty); 12330196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman } 123492fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *RHS = expandCodeFor(S->getOperand(i), Ty); 1235267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *ICmp = Builder.CreateICmpUGT(LHS, RHS, "tmp"); 1236a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(ICmp); 1237267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *Sel = Builder.CreateSelect(ICmp, LHS, RHS, "umax"); 1238a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(Sel); 1239cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman LHS = Sel; 12403e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky } 12410196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, cast the 12420196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // final result back to the pointer type. 12430196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (LHS->getType() != S->getType()) 12440196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, S->getType()); 12453e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky return LHS; 12463e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky} 12473e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky 12486c7ed6b54949949806797bafdf545fbfecb2cef5Dan GohmanValue *SCEVExpander::expandCodeFor(const SCEV *SH, const Type *Ty, 12496c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman Instruction *I) { 12506c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman BasicBlock::iterator IP = I; 12516c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman while (isInsertedInstruction(IP) || isa<DbgInfoIntrinsic>(IP)) 12526c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman ++IP; 12536c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman Builder.SetInsertPoint(IP->getParent(), IP); 12546c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman return expandCodeFor(SH, Ty); 12556c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman} 12566c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman 12570bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan GohmanValue *SCEVExpander::expandCodeFor(const SCEV *SH, const Type *Ty) { 125811f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman // Expand the code for this SCEV. 12592d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman Value *V = expand(SH); 12605be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (Ty) { 12615be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman assert(SE.getTypeSizeInBits(Ty) == SE.getTypeSizeInBits(SH->getType()) && 12625be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman "non-trivial casts should be done with the SCEVs directly!"); 12635be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman V = InsertNoopCastOfTo(V, Ty); 12645be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 12655be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return V; 126611f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 126711f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 1268890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::expand(const SCEV *S) { 126940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // Compute an insertion point for this SCEV object. Hoist the instructions 127040a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // as far out in the loop nest as possible. 1271267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction *InsertPt = Builder.GetInsertPoint(); 1272267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman for (Loop *L = SE.LI->getLoopFor(Builder.GetInsertBlock()); ; 127340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman L = L->getParentLoop()) 127440a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (S->isLoopInvariant(L)) { 127540a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (!L) break; 1276e059ee832ca36d65a5fb87b0ac5bcdb0490b15cbDan Gohman if (BasicBlock *Preheader = L->getLoopPreheader()) 127740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman InsertPt = Preheader->getTerminator(); 127840a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman } else { 127940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // If the SCEV is computable at this level, insert it into the header 128040a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // after the PHIs (and after any other instructions that we've inserted 128140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // there) so that it is guaranteed to dominate any user inside the loop. 1282448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman if (L && S->hasComputableLoopEvolution(L) && !PostIncLoops.count(L)) 128340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman InsertPt = L->getHeader()->getFirstNonPHI(); 12846c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman while (isInsertedInstruction(InsertPt) || isa<DbgInfoIntrinsic>(InsertPt)) 12857896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner InsertPt = llvm::next(BasicBlock::iterator(InsertPt)); 128640a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman break; 128740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman } 128840a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman 1289667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman // Check to see if we already expanded this here. 1290667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman std::map<std::pair<const SCEV *, Instruction *>, 1291667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman AssertingVH<Value> >::iterator I = 1292667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman InsertedExpressions.find(std::make_pair(S, InsertPt)); 1293267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (I != InsertedExpressions.end()) 1294667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman return I->second; 1295267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman 1296267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 1297267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 1298267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Builder.SetInsertPoint(InsertPt->getParent(), InsertPt); 1299667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman 1300667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman // Expand the expression into instructions. 130196fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov Value *V = visit(S); 130240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman 1303667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman // Remember the expanded value for this SCEV at this location. 1304448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman if (PostIncLoops.empty()) 1305a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman InsertedExpressions[std::make_pair(S, InsertPt)] = V; 1306667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman 1307455985501381777db03534c925a35e261e356395Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 130896fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov return V; 130996fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov} 13101d09de3eca23267855e28297fcb40de3632ea47bDan Gohman 13111d826a76f591afea445489b9a5485c345e66bf87Dan Gohmanvoid SCEVExpander::rememberInstruction(Value *I) { 1312448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman if (PostIncLoops.empty()) 13131d826a76f591afea445489b9a5485c345e66bf87Dan Gohman InsertedValues.insert(I); 13141d826a76f591afea445489b9a5485c345e66bf87Dan Gohman 13151d826a76f591afea445489b9a5485c345e66bf87Dan Gohman // If we just claimed an existing instruction and that instruction had 13161d826a76f591afea445489b9a5485c345e66bf87Dan Gohman // been the insert point, adjust the insert point forward so that 13171d826a76f591afea445489b9a5485c345e66bf87Dan Gohman // subsequently inserted code will be dominated. 13181d826a76f591afea445489b9a5485c345e66bf87Dan Gohman if (Builder.GetInsertPoint() == I) { 13191d826a76f591afea445489b9a5485c345e66bf87Dan Gohman BasicBlock::iterator It = cast<Instruction>(I); 13206c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman do { ++It; } while (isInsertedInstruction(It) || 13216c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman isa<DbgInfoIntrinsic>(It)); 13221d826a76f591afea445489b9a5485c345e66bf87Dan Gohman Builder.SetInsertPoint(Builder.GetInsertBlock(), It); 13231d826a76f591afea445489b9a5485c345e66bf87Dan Gohman } 13241d826a76f591afea445489b9a5485c345e66bf87Dan Gohman} 13251d826a76f591afea445489b9a5485c345e66bf87Dan Gohman 1326455985501381777db03534c925a35e261e356395Dan Gohmanvoid SCEVExpander::restoreInsertPoint(BasicBlock *BB, BasicBlock::iterator I) { 13273f46a3abeedba8d517b4182de34c821d752db058Dan Gohman // If we acquired more instructions since the old insert point was saved, 1328455985501381777db03534c925a35e261e356395Dan Gohman // advance past them. 13296c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman while (isInsertedInstruction(I) || isa<DbgInfoIntrinsic>(I)) ++I; 1330455985501381777db03534c925a35e261e356395Dan Gohman 1331455985501381777db03534c925a35e261e356395Dan Gohman Builder.SetInsertPoint(BB, I); 1332455985501381777db03534c925a35e261e356395Dan Gohman} 1333455985501381777db03534c925a35e261e356395Dan Gohman 13341d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// getOrInsertCanonicalInductionVariable - This method returns the 13351d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// canonical induction variable of the specified type for the specified 13361d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// loop (inserting one if there is none). A canonical induction variable 13371d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// starts at zero and steps by one on each iteration. 13381d09de3eca23267855e28297fcb40de3632ea47bDan GohmanValue * 13391d09de3eca23267855e28297fcb40de3632ea47bDan GohmanSCEVExpander::getOrInsertCanonicalInductionVariable(const Loop *L, 13401d09de3eca23267855e28297fcb40de3632ea47bDan Gohman const Type *Ty) { 1341b0bc6c361da9009e8414efde317d9bbff755f6c0Duncan Sands assert(Ty->isIntegerTy() && "Can only insert integer induction variables!"); 13420bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *H = SE.getAddRecExpr(SE.getIntegerSCEV(0, Ty), 134340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman SE.getIntegerSCEV(1, Ty), L); 1344267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 1345267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 134640a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman Value *V = expandCodeFor(H, 0, L->getHeader()->begin()); 1347267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (SaveInsertBB) 1348455985501381777db03534c925a35e261e356395Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 134940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return V; 13501d09de3eca23267855e28297fcb40de3632ea47bDan Gohman} 1351