ScalarEvolutionExpander.cpp revision 4c0d5d5db876b0628bdf6a2174263a1c0a9130e2
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" 1876f600b205606a055ec35e7d3fd1a99602329d67Owen Anderson#include "llvm/LLVMContext.h" 195be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman#include "llvm/Target/TargetData.h" 204d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman#include "llvm/ADT/STLExtras.h" 2136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begemanusing namespace llvm; 2236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 23267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman/// InsertNoopCastOfTo - Insert a cast of V to the specified type, 24267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman/// which must be possible with a noop cast, doing what we can to share 25267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman/// the casts. 26267a385342f2e7388f178b327dd87c5f29afd51bDan GohmanValue *SCEVExpander::InsertNoopCastOfTo(Value *V, const Type *Ty) { 27267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction::CastOps Op = CastInst::getCastOpcode(V, false, Ty, false); 28267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman assert((Op == Instruction::BitCast || 29267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Op == Instruction::PtrToInt || 30267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Op == Instruction::IntToPtr) && 31267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman "InsertNoopCastOfTo cannot perform non-noop casts!"); 32267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman assert(SE.getTypeSizeInBits(V->getType()) == SE.getTypeSizeInBits(Ty) && 33267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman "InsertNoopCastOfTo cannot change sizes!"); 34267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman 352d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman // Short-circuit unnecessary bitcasts. 36267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (Op == Instruction::BitCast && V->getType() == Ty) 372d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman return V; 382d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman 39f04fa483b83227c570bc58e1684ea096430a6697Dan Gohman // Short-circuit unnecessary inttoptr<->ptrtoint casts. 40267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if ((Op == Instruction::PtrToInt || Op == Instruction::IntToPtr) && 4180dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman SE.getTypeSizeInBits(Ty) == SE.getTypeSizeInBits(V->getType())) { 42af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman if (CastInst *CI = dyn_cast<CastInst>(V)) 43af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman if ((CI->getOpcode() == Instruction::PtrToInt || 44af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman CI->getOpcode() == Instruction::IntToPtr) && 45af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman SE.getTypeSizeInBits(CI->getType()) == 46af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman SE.getTypeSizeInBits(CI->getOperand(0)->getType())) 47af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman return CI->getOperand(0); 4880dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) 4980dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman if ((CE->getOpcode() == Instruction::PtrToInt || 5080dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman CE->getOpcode() == Instruction::IntToPtr) && 5180dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman SE.getTypeSizeInBits(CE->getType()) == 5280dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman SE.getTypeSizeInBits(CE->getOperand(0)->getType())) 5380dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman return CE->getOperand(0); 5480dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman } 55f04fa483b83227c570bc58e1684ea096430a6697Dan Gohman 56ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if (Constant *C = dyn_cast<Constant>(V)) 57baf3c404409d5e47b13984a7f95bfbd6d1f2e79eOwen Anderson return ConstantExpr::getCast(Op, C, Ty); 584c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman 59ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if (Argument *A = dyn_cast<Argument>(V)) { 60ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner // Check to see if there is already a cast! 61ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner for (Value::use_iterator UI = A->use_begin(), E = A->use_end(); 6240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman UI != E; ++UI) 63ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if ((*UI)->getType() == Ty) 643913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz if (CastInst *CI = dyn_cast<CastInst>(cast<Instruction>(*UI))) 65267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (CI->getOpcode() == Op) { 663913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz // If the cast isn't the first instruction of the function, move it. 6740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (BasicBlock::iterator(CI) != 683913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz A->getParent()->getEntryBlock().begin()) { 6940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // Recreate the cast at the beginning of the entry block. 7040a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // The old cast is left in place in case it is being used 7140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // as an insert point. 7240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman Instruction *NewCI = 73267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman CastInst::Create(Op, V, Ty, "", 7440a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman A->getParent()->getEntryBlock().begin()); 7540a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman NewCI->takeName(CI); 7640a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman CI->replaceAllUsesWith(NewCI); 7740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return NewCI; 783913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz } 793913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz return CI; 80ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner } 8140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman 82267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction *I = CastInst::Create(Op, V, Ty, V->getName(), 83cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman A->getParent()->getEntryBlock().begin()); 84cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(I); 85cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return I; 86ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner } 873913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz 88ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner Instruction *I = cast<Instruction>(V); 893913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz 90ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner // Check to see if there is already a cast. If there is, use it. 91ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); 92ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner UI != E; ++UI) { 93ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if ((*UI)->getType() == Ty) 943913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz if (CastInst *CI = dyn_cast<CastInst>(cast<Instruction>(*UI))) 95267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (CI->getOpcode() == Op) { 963913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz BasicBlock::iterator It = I; ++It; 973913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz if (isa<InvokeInst>(I)) 983913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz It = cast<InvokeInst>(I)->getNormalDest()->begin(); 993913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz while (isa<PHINode>(It)) ++It; 1003913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz if (It != BasicBlock::iterator(CI)) { 10140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // Recreate the cast at the beginning of the entry block. 10240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // The old cast is left in place in case it is being used 10340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // as an insert point. 104267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction *NewCI = CastInst::Create(Op, V, Ty, "", It); 10540a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman NewCI->takeName(CI); 10640a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman CI->replaceAllUsesWith(NewCI); 10740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return NewCI; 1083913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz } 1093913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz return CI; 110ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner } 111ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner } 112ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner BasicBlock::iterator IP = I; ++IP; 113ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if (InvokeInst *II = dyn_cast<InvokeInst>(I)) 114ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner IP = II->getNormalDest()->begin(); 115ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner while (isa<PHINode>(IP)) ++IP; 116267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction *CI = CastInst::Create(Op, V, Ty, V->getName(), IP); 117cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(CI); 118cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return CI; 119ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner} 120ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner 1217fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner/// InsertBinop - Insert the specified binary operator, doing a small amount 1227fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner/// of work to avoid inserting an obviously redundant operation. 123267a385342f2e7388f178b327dd87c5f29afd51bDan GohmanValue *SCEVExpander::InsertBinop(Instruction::BinaryOps Opcode, 124267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *LHS, Value *RHS) { 1250f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman // Fold a binop with constant operands. 1260f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman if (Constant *CLHS = dyn_cast<Constant>(LHS)) 1270f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman if (Constant *CRHS = dyn_cast<Constant>(RHS)) 128baf3c404409d5e47b13984a7f95bfbd6d1f2e79eOwen Anderson return ConstantExpr::get(Opcode, CLHS, CRHS); 1290f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman 1307fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner // Do a quick scan to see if we have this binop nearby. If so, reuse it. 1317fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner unsigned ScanLimit = 6; 132267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator BlockBegin = Builder.GetInsertBlock()->begin(); 133267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman // Scanning starts from the last instruction before the insertion point. 134267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator IP = Builder.GetInsertPoint(); 135267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (IP != BlockBegin) { 1368a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz --IP; 1378a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz for (; ScanLimit; --IP, --ScanLimit) { 1385be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (IP->getOpcode() == (unsigned)Opcode && IP->getOperand(0) == LHS && 1395be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman IP->getOperand(1) == RHS) 1405be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return IP; 1418a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz if (IP == BlockBegin) break; 1428a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz } 1437fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner } 144267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman 1458a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz // If we haven't found this binop, insert it. 146267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *BO = Builder.CreateBinOp(Opcode, LHS, RHS, "tmp"); 147cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(BO); 148cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return BO; 1497fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner} 1507fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner 1514a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman/// FactorOutConstant - Test if S is divisible by Factor, using signed 152453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// division. If so, update S with Factor divided out and return true. 1534a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman/// S need not be evenly divisble if a reasonable remainder can be 1544a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman/// computed. 155453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// TODO: When ScalarEvolution gets a SCEVSDivExpr, this can be made 156453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// unnecessary; in its place, just signed-divide Ops[i] by the scale and 157453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// check to see if the divide was folded. 1580bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohmanstatic bool FactorOutConstant(const SCEV *&S, 1590bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *&Remainder, 160c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Factor, 161c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ScalarEvolution &SE, 162c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const TargetData *TD) { 163453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // Everything is divisible by one. 164c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (Factor->isOne()) 165c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 166c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 167c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // x/x == 1. 168c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (S == Factor) { 169c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman S = SE.getIntegerSCEV(1, S->getType()); 170453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return true; 171c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 172453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 173453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // For a Constant, check for a multiple of the given factor. 1744a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman if (const SCEVConstant *C = dyn_cast<SCEVConstant>(S)) { 175c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // 0/x == 0. 176c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (C->isZero()) 177453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return true; 178c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Check for divisibility. 179c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVConstant *FC = dyn_cast<SCEVConstant>(Factor)) { 180c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ConstantInt *CI = 181c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ConstantInt::get(SE.getContext(), 182c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman C->getValue()->getValue().sdiv( 183c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FC->getValue()->getValue())); 184c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If the quotient is zero and the remainder is non-zero, reject 185c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // the value at this scale. It will be considered for subsequent 186c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // smaller scales. 187c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!CI->isZero()) { 188c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Div = SE.getConstant(CI); 189c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman S = Div; 190c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Remainder = 191c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getAddExpr(Remainder, 192c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getConstant(C->getValue()->getValue().srem( 193c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FC->getValue()->getValue()))); 194c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 195c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 196453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 1974a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman } 198453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 199453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // In a Mul, check if there is a constant operand which is a multiple 200453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // of the given factor. 201c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVMulExpr *M = dyn_cast<SCEVMulExpr>(S)) { 202c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (TD) { 203c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // With TargetData, the size is known. Check if there is a constant 204c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // operand which is a multiple of the given factor. If so, we can 205c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // factor it. 206c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEVConstant *FC = cast<SCEVConstant>(Factor); 207c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVConstant *C = dyn_cast<SCEVConstant>(M->getOperand(0))) 208c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!C->getValue()->getValue().srem(FC->getValue()->getValue())) { 209c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SmallVectorImpl<const SCEV *> &MOperands = M->getOperands(); 210c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 4> NewMulOps(MOperands.begin(), 211c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman MOperands.end()); 212c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman NewMulOps[0] = 213c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getConstant(C->getValue()->getValue().sdiv( 214c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FC->getValue()->getValue())); 215c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman S = SE.getMulExpr(NewMulOps); 216c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 217c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 218c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } else { 219c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Without TargetData, check if Factor can be factored out of any of the 220c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Mul's operands. If so, we can just remove it. 221c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = 0, e = M->getNumOperands(); i != e; ++i) { 222c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *SOp = M->getOperand(i); 223c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Remainder = SE.getIntegerSCEV(0, SOp->getType()); 224c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (FactorOutConstant(SOp, Remainder, Factor, SE, TD) && 225c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Remainder->isZero()) { 226c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SmallVectorImpl<const SCEV *> &MOperands = M->getOperands(); 227c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 4> NewMulOps(MOperands.begin(), 228c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman MOperands.end()); 229c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman NewMulOps[i] = SOp; 230c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman S = SE.getMulExpr(NewMulOps); 231c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 232c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 233453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 234c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 235c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 236453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 237453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // In an AddRec, check if both start and step are divisible. 238453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman if (const SCEVAddRecExpr *A = dyn_cast<SCEVAddRecExpr>(S)) { 2390bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *Step = A->getStepRecurrence(SE); 2400bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *StepRem = SE.getIntegerSCEV(0, Step->getType()); 241c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!FactorOutConstant(Step, StepRem, Factor, SE, TD)) 2424a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman return false; 2434a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman if (!StepRem->isZero()) 2444a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman return false; 2450bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *Start = A->getStart(); 246c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!FactorOutConstant(Start, Remainder, Factor, SE, TD)) 247453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return false; 248453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman S = SE.getAddRecExpr(Start, Step, A->getLoop()); 249453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return true; 250453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 251453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 252453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return false; 253453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman} 254453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 255c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// SimplifyAddOperands - Sort and simplify a list of add operands. NumAddRecs 256c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// is the number of SCEVAddRecExprs present, which are kept at the end of 257c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// the list. 258c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// 259c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohmanstatic void SimplifyAddOperands(SmallVectorImpl<const SCEV *> &Ops, 260c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const Type *Ty, 261c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ScalarEvolution &SE) { 262c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman unsigned NumAddRecs = 0; 263c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = Ops.size(); i > 0 && isa<SCEVAddRecExpr>(Ops[i-1]); --i) 264c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ++NumAddRecs; 265c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Group Ops into non-addrecs and addrecs. 266c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 8> NoAddRecs(Ops.begin(), Ops.end() - NumAddRecs); 267c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 8> AddRecs(Ops.end() - NumAddRecs, Ops.end()); 268c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Let ScalarEvolution sort and simplify the non-addrecs list. 269c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Sum = NoAddRecs.empty() ? 270c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getIntegerSCEV(0, Ty) : 271c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getAddExpr(NoAddRecs); 272c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If it returned an add, use the operands. Otherwise it simplified 273c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // the sum into a single value, so just use that. 274c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(Sum)) 275c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops = Add->getOperands(); 276c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman else { 277c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops.clear(); 278c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!Sum->isZero()) 279c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops.push_back(Sum); 280c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 281c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Then append the addrecs. 282c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops.insert(Ops.end(), AddRecs.begin(), AddRecs.end()); 283c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman} 284c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 285c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// SplitAddRecs - Flatten a list of add operands, moving addrec start values 286c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// out to the top level. For example, convert {a + b,+,c} to a, b, {0,+,d}. 287c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// This helps expose more opportunities for folding parts of the expressions 288c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// into GEP indices. 289c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// 290c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohmanstatic void SplitAddRecs(SmallVectorImpl<const SCEV *> &Ops, 291c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const Type *Ty, 292c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ScalarEvolution &SE) { 293c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Find the addrecs. 294c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 8> AddRecs; 295c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = 0, e = Ops.size(); i != e; ++i) 296c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman while (const SCEVAddRecExpr *A = dyn_cast<SCEVAddRecExpr>(Ops[i])) { 297c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Start = A->getStart(); 298c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (Start->isZero()) break; 299c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Zero = SE.getIntegerSCEV(0, Ty); 300c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman AddRecs.push_back(SE.getAddRecExpr(Zero, 301c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman A->getStepRecurrence(SE), 302c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman A->getLoop())); 303c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(Start)) { 304c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops[i] = Zero; 305c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops.insert(Ops.end(), Add->op_begin(), Add->op_end()); 306c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman e += Add->getNumOperands(); 307c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } else { 308c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops[i] = Start; 309c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 310c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 311c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!AddRecs.empty()) { 312c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Add the addrecs onto the end of the list. 313c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops.insert(Ops.end(), AddRecs.begin(), AddRecs.end()); 314c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Resort the operand list, moving any constants to the front. 315c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SimplifyAddOperands(Ops, Ty, SE); 316c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 317c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman} 318c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 3194c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// expandAddToGEP - Expand an addition expression with a pointer type into 3204c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// a GEP instead of using ptrtoint+arithmetic+inttoptr. This helps 3214c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// BasicAliasAnalysis and other passes analyze the result. See the rules 3224c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// for getelementptr vs. inttoptr in 3234c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// http://llvm.org/docs/LangRef.html#pointeraliasing 3244c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// for details. 32513c5e35222afe0895f0c5e68aa9f22f134ea437aDan Gohman/// 3264c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// Design note: The correctness of using getelmeentptr here depends on 3274c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// ScalarEvolution not recognizing inttoptr and ptrtoint operators, as 3284c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// they may introduce pointer arithmetic which may not be safely converted 3294c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman/// into getelementptr. 330453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// 331453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// Design note: It might seem desirable for this function to be more 332453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// loop-aware. If some of the indices are loop-invariant while others 333453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// aren't, it might seem desirable to emit multiple GEPs, keeping the 334453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// loop-invariant portions of the overall computation outside the loop. 335453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// However, there are a few reasons this is not done here. Hoisting simple 336453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// arithmetic is a low-level optimization that often isn't very 337453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// important until late in the optimization process. In fact, passes 338453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// like InstructionCombining will combine GEPs, even if it means 339453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// pushing loop-invariant computation down into loops, so even if the 340453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// GEPs were split here, the work would quickly be undone. The 341453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// LoopStrengthReduction pass, which is usually run quite late (and 342453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// after the last InstructionCombining pass), takes care of hoisting 343453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// loop-invariant portions of expressions, after considering what 344453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// can be folded using target addressing modes. 345453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// 3460bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan GohmanValue *SCEVExpander::expandAddToGEP(const SCEV *const *op_begin, 3470bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *const *op_end, 3485be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman const PointerType *PTy, 3495be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman const Type *Ty, 3505be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman Value *V) { 3515be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman const Type *ElTy = PTy->getElementType(); 3525be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman SmallVector<Value *, 4> GepIndices; 3530bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman SmallVector<const SCEV *, 8> Ops(op_begin, op_end); 3545be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman bool AnyNonZeroIndices = false; 3555be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 356c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Split AddRecs up into parts as either of the parts may be usable 357c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // without the other. 358c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SplitAddRecs(Ops, Ty, SE); 359c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 3605be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // Decend down the pointer's type and attempt to convert the other 3615be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // operands into GEP indices, at each level. The first index in a GEP 3625be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // indexes into the array implied by the pointer operand; the rest of 3635be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // the indices index into the element or field type selected by the 3645be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // preceding index. 3655be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman for (;;) { 366c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *ElSize = SE.getAllocSizeExpr(ElTy); 367c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If the scale size is not 0, attempt to factor out a scale for 368c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // array indexing. 3690bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman SmallVector<const SCEV *, 8> ScaledOps; 370c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (ElTy->isSized() && !ElSize->isZero()) { 371c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 8> NewOps; 372c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = 0, e = Ops.size(); i != e; ++i) { 3730bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *Op = Ops[i]; 374c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Remainder = SE.getIntegerSCEV(0, Ty); 375c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (FactorOutConstant(Op, Remainder, ElSize, SE, SE.TD)) { 376c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Op now has ElSize factored out. 377c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ScaledOps.push_back(Op); 378c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!Remainder->isZero()) 379c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman NewOps.push_back(Remainder); 380c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman AnyNonZeroIndices = true; 381c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } else { 382c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // The operand was not divisible, so add it to the list of operands 383c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // we'll scan next iteration. 384c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman NewOps.push_back(Ops[i]); 3855be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 3865be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 387c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If we made any changes, update Ops. 388c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!ScaledOps.empty()) { 389c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops = NewOps; 390c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SimplifyAddOperands(Ops, Ty, SE); 391c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 3925be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 393c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 394c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Record the scaled array index for this level of the type. If 395c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // we didn't find any operands that could be factored, tentatively 396c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // assume that element zero was selected (since the zero offset 397c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // would obviously be folded away). 3985be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman Value *Scaled = ScaledOps.empty() ? 399a7235ea7245028a0723e8ab7fd011386b3900777Owen Anderson Constant::getNullValue(Ty) : 4005be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman expandCodeFor(SE.getAddExpr(ScaledOps), Ty); 4015be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman GepIndices.push_back(Scaled); 4025be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 4035be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // Collect struct field index operands. 404c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman while (const StructType *STy = dyn_cast<StructType>(ElTy)) { 405c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman bool FoundFieldNo = false; 406c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // An empty struct has no fields. 407c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (STy->getNumElements() == 0) break; 408c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (SE.TD) { 409c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // With TargetData, field offsets are known. See if a constant offset 410c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // falls within any of the struct fields. 411c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (Ops.empty()) break; 4125be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (const SCEVConstant *C = dyn_cast<SCEVConstant>(Ops[0])) 4135be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (SE.getTypeSizeInBits(C->getType()) <= 64) { 4145be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman const StructLayout &SL = *SE.TD->getStructLayout(STy); 4155be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman uint64_t FullOffset = C->getValue()->getZExtValue(); 4165be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (FullOffset < SL.getSizeInBytes()) { 4175be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman unsigned ElIdx = SL.getElementContainingOffset(FullOffset); 4181d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson GepIndices.push_back( 4191d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson ConstantInt::get(Type::getInt32Ty(Ty->getContext()), ElIdx)); 4205be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman ElTy = STy->getTypeAtIndex(ElIdx); 4215be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman Ops[0] = 4226de29f8d960505421d61c80cdb738e16720b6c0eDan Gohman SE.getConstant(Ty, FullOffset - SL.getElementOffset(ElIdx)); 4235be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman AnyNonZeroIndices = true; 424c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FoundFieldNo = true; 4255be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 4265be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 427c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } else { 428c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Without TargetData, just check for a SCEVFieldOffsetExpr of the 429c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // appropriate struct type. 430c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = 0, e = Ops.size(); i != e; ++i) 431c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVFieldOffsetExpr *FO = 432c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman dyn_cast<SCEVFieldOffsetExpr>(Ops[i])) 433c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (FO->getStructType() == STy) { 434c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman unsigned FieldNo = FO->getFieldNo(); 435c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman GepIndices.push_back( 436c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ConstantInt::get(Type::getInt32Ty(Ty->getContext()), 437c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FieldNo)); 438c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ElTy = STy->getTypeAtIndex(FieldNo); 439c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops[i] = SE.getConstant(Ty, 0); 440c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman AnyNonZeroIndices = true; 441c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FoundFieldNo = true; 442c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman break; 443c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 4445be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 445c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If no struct field offsets were found, tentatively assume that 446c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // field zero was selected (since the zero offset would obviously 447c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // be folded away). 448c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!FoundFieldNo) { 449c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ElTy = STy->getTypeAtIndex(0u); 450c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman GepIndices.push_back( 451c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Constant::getNullValue(Type::getInt32Ty(Ty->getContext()))); 452c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 453c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 4545be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 455c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const ArrayType *ATy = dyn_cast<ArrayType>(ElTy)) 4565be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman ElTy = ATy->getElementType(); 457c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman else 458c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman break; 4595be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 4605be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 4615be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // If none of the operands were convertable to proper GEP indices, cast 4625be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // the base to i8* and do an ugly getelementptr with that. It's still 4635be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // better than ptrtoint+arithmetic+inttoptr at least. 4645be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (!AnyNonZeroIndices) { 465c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Cast the base to i8*. 4665be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman V = InsertNoopCastOfTo(V, 4671d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson Type::getInt8Ty(Ty->getContext())->getPointerTo(PTy->getAddressSpace())); 468c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 469c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Expand the operands for a plain byte offset. 47092fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *Idx = expandCodeFor(SE.getAddExpr(Ops), Ty); 4715be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 4725be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // Fold a GEP with constant operands. 4735be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (Constant *CLHS = dyn_cast<Constant>(V)) 4745be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (Constant *CRHS = dyn_cast<Constant>(Idx)) 475baf3c404409d5e47b13984a7f95bfbd6d1f2e79eOwen Anderson return ConstantExpr::getGetElementPtr(CLHS, &CRHS, 1); 4765be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 4775be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman // Do a quick scan to see if we have this GEP nearby. If so, reuse it. 4785be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman unsigned ScanLimit = 6; 479267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator BlockBegin = Builder.GetInsertBlock()->begin(); 480267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman // Scanning starts from the last instruction before the insertion point. 481267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator IP = Builder.GetInsertPoint(); 482267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (IP != BlockBegin) { 4835be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman --IP; 4845be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman for (; ScanLimit; --IP, --ScanLimit) { 4855be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (IP->getOpcode() == Instruction::GetElementPtr && 4865be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman IP->getOperand(0) == V && IP->getOperand(1) == Idx) 4875be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return IP; 4885be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (IP == BlockBegin) break; 4895be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 4905be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 4915be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 492c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Emit a GEP. 493c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Value *GEP = Builder.CreateGEP(V, Idx, "uglygep"); 4945be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman InsertedValues.insert(GEP); 4955be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return GEP; 4965be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 4975be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 498d6aa02de1076c801ac41295156a2379637976918Dan Gohman // Insert a pretty getelementptr. Note that this GEP is not marked inbounds, 499d6aa02de1076c801ac41295156a2379637976918Dan Gohman // because ScalarEvolution may have changed the address arithmetic to 500d6aa02de1076c801ac41295156a2379637976918Dan Gohman // compute a value which is beyond the end of the allocated object. 501267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *GEP = Builder.CreateGEP(V, 502267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman GepIndices.begin(), 503267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman GepIndices.end(), 504267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman "scevgep"); 5055be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman Ops.push_back(SE.getUnknown(GEP)); 5065be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman InsertedValues.insert(GEP); 5075be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return expand(SE.getAddExpr(Ops)); 5085be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman} 5095be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 510890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitAddExpr(const SCEVAddExpr *S) { 511af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 512e24fa64d52330626553298f56ba5aa702624c282Dan Gohman Value *V = expand(S->getOperand(S->getNumOperands()-1)); 5135be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 514453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // Turn things like ptrtoint+arithmetic+inttoptr into GEP. See the 515453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // comments on expandAddToGEP for details. 516c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const PointerType *PTy = dyn_cast<PointerType>(V->getType())) { 517c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SmallVectorImpl<const SCEV *> &Ops = S->getOperands(); 518c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return expandAddToGEP(&Ops[0], &Ops[Ops.size() - 1], PTy, Ty, V); 519c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 5205be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 521af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman V = InsertNoopCastOfTo(V, Ty); 522e24fa64d52330626553298f56ba5aa702624c282Dan Gohman 523e24fa64d52330626553298f56ba5aa702624c282Dan Gohman // Emit a bunch of add instructions 5242d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman for (int i = S->getNumOperands()-2; i >= 0; --i) { 52592fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *W = expandCodeFor(S->getOperand(i), Ty); 526267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman V = InsertBinop(Instruction::Add, V, W); 5272d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman } 528e24fa64d52330626553298f56ba5aa702624c282Dan Gohman return V; 529e24fa64d52330626553298f56ba5aa702624c282Dan Gohman} 5305be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 531890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitMulExpr(const SCEVMulExpr *S) { 532af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 53336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman int FirstOp = 0; // Set if we should emit a subtract. 534890f92b744fb074465bc2b7006ee753a181f62a4Dan Gohman if (const SCEVConstant *SC = dyn_cast<SCEVConstant>(S->getOperand(0))) 53536f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman if (SC->getValue()->isAllOnesValue()) 53636f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman FirstOp = 1; 53736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 53836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman int i = S->getNumOperands()-2; 53992fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *V = expandCodeFor(S->getOperand(i+1), Ty); 54036f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 54136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // Emit a bunch of multiply instructions 5422d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman for (; i >= FirstOp; --i) { 54392fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *W = expandCodeFor(S->getOperand(i), Ty); 544267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman V = InsertBinop(Instruction::Mul, V, W); 5452d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman } 5462d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman 54736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // -1 * ... ---> 0 - ... 54836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman if (FirstOp == 1) 549a7235ea7245028a0723e8ab7fd011386b3900777Owen Anderson V = InsertBinop(Instruction::Sub, Constant::getNullValue(Ty), V); 55036f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman return V; 55136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman} 55236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 553890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitUDivExpr(const SCEVUDivExpr *S) { 554af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 5552d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman 55692fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *LHS = expandCodeFor(S->getLHS(), Ty); 557890f92b744fb074465bc2b7006ee753a181f62a4Dan Gohman if (const SCEVConstant *SC = dyn_cast<SCEVConstant>(S->getRHS())) { 5586177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky const APInt &RHS = SC->getValue()->getValue(); 5596177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky if (RHS.isPowerOf2()) 5606177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky return InsertBinop(Instruction::LShr, LHS, 561eed707b1e6097aac2bb6b3d47271f6300ace7f2eOwen Anderson ConstantInt::get(Ty, RHS.logBase2())); 5626177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky } 5636177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky 56492fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *RHS = expandCodeFor(S->getRHS(), Ty); 565267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman return InsertBinop(Instruction::UDiv, LHS, RHS); 5666177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky} 5676177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky 568453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// Move parts of Base into Rest to leave Base with the minimal 569453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// expression that provides a pointer operand suitable for a 570453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// GEP expansion. 5710bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohmanstatic void ExposePointerBase(const SCEV *&Base, const SCEV *&Rest, 572453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman ScalarEvolution &SE) { 573453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman while (const SCEVAddRecExpr *A = dyn_cast<SCEVAddRecExpr>(Base)) { 574453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Base = A->getStart(); 575453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Rest = SE.getAddExpr(Rest, 576453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman SE.getAddRecExpr(SE.getIntegerSCEV(0, A->getType()), 577453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman A->getStepRecurrence(SE), 578453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman A->getLoop())); 579453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 580453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman if (const SCEVAddExpr *A = dyn_cast<SCEVAddExpr>(Base)) { 581453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Base = A->getOperand(A->getNumOperands()-1); 5820bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman SmallVector<const SCEV *, 8> NewAddOps(A->op_begin(), A->op_end()); 583453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman NewAddOps.back() = Rest; 584453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Rest = SE.getAddExpr(NewAddOps); 585453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman ExposePointerBase(Base, Rest, SE); 586453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 587453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman} 588453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 589890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitAddRecExpr(const SCEVAddRecExpr *S) { 590af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 59136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman const Loop *L = S->getLoop(); 59236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 5934d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // First check for an existing canonical IV in a suitable type. 5944d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman PHINode *CanonicalIV = 0; 5954d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (PHINode *PN = L->getCanonicalInductionVariable()) 5964d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (SE.isSCEVable(PN->getType()) && 5974d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman isa<IntegerType>(SE.getEffectiveSCEVType(PN->getType())) && 5984d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman SE.getTypeSizeInBits(PN->getType()) >= SE.getTypeSizeInBits(Ty)) 5994d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman CanonicalIV = PN; 6004d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman 6014d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // Rewrite an AddRec in terms of the canonical induction variable, if 6024d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // its type is more narrow. 6034d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (CanonicalIV && 6044d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman SE.getTypeSizeInBits(CanonicalIV->getType()) > 6054d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman SE.getTypeSizeInBits(Ty)) { 6065001c21712f2e52fd6254461b2b2edb9a5823d23Dan Gohman const SCEV *Start = SE.getAnyExtendExpr(S->getStart(), 6075001c21712f2e52fd6254461b2b2edb9a5823d23Dan Gohman CanonicalIV->getType()); 6085001c21712f2e52fd6254461b2b2edb9a5823d23Dan Gohman const SCEV *Step = SE.getAnyExtendExpr(S->getStepRecurrence(SE), 6094d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman CanonicalIV->getType()); 6104d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman Value *V = expand(SE.getAddRecExpr(Start, Step, S->getLoop())); 611267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 612267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 6134d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman BasicBlock::iterator NewInsertPt = 6144d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman next(BasicBlock::iterator(cast<Instruction>(V))); 6154d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman while (isa<PHINode>(NewInsertPt)) ++NewInsertPt; 6164d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman V = expandCodeFor(SE.getTruncateExpr(SE.getUnknown(V), Ty), 0, 6174d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman NewInsertPt); 618267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Builder.SetInsertPoint(SaveInsertBB, SaveInsertPt); 6194d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman return V; 6204d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman } 6214d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman 62236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // {X,+,F} --> X + {0,+,F} 623cfeb6a450632f2a6cd05302633c8c2b8c90cfdfdDan Gohman if (!S->getStart()->isZero()) { 6240bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SmallVectorImpl<const SCEV *> &SOperands = S->getOperands(); 6250bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman SmallVector<const SCEV *, 4> NewOps(SOperands.begin(), SOperands.end()); 626246b2564d3bbbafe06ebf6a67745cd24141b5cb4Dan Gohman NewOps[0] = SE.getIntegerSCEV(0, Ty); 6270bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *Rest = SE.getAddRecExpr(NewOps, L); 628453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 629453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // Turn things like ptrtoint+arithmetic+inttoptr into GEP. See the 630453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // comments on expandAddToGEP for details. 631c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Base = S->getStart(); 632c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *RestArray[1] = { Rest }; 633c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Dig into the expression to find the pointer base for a GEP. 634c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ExposePointerBase(Base, RestArray[0], SE); 635c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If we found a pointer, expand the AddRec with a GEP. 636c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const PointerType *PTy = dyn_cast<PointerType>(Base->getType())) { 637c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Make sure the Base isn't something exotic, such as a multiplied 638c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // or divided pointer value. In those cases, the result type isn't 639c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // actually a pointer type. 640c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!isa<SCEVMulExpr>(Base) && !isa<SCEVUDivExpr>(Base)) { 641c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Value *StartV = expand(Base); 642c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman assert(StartV->getType() == PTy && "Pointer type mismatch for GEP!"); 643c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return expandAddToGEP(RestArray, RestArray+1, PTy, Ty, StartV); 644453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 645453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 646453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 64740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // Just do a normal add. Pre-expand the operands to suppress folding. 64840a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return expand(SE.getAddExpr(SE.getUnknown(expand(S->getStart())), 64940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman SE.getUnknown(expand(Rest)))); 65036f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman } 65136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 65236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // {0,+,1} --> Insert a canonical induction variable into the loop! 65317f1972c770dc18f5c7c3c95776b4d62ae9e121dDan Gohman if (S->isAffine() && 654246b2564d3bbbafe06ebf6a67745cd24141b5cb4Dan Gohman S->getOperand(1) == SE.getIntegerSCEV(1, Ty)) { 6554d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // If there's a canonical IV, just use it. 6564d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (CanonicalIV) { 6574d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman assert(Ty == SE.getEffectiveSCEVType(CanonicalIV->getType()) && 6584d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman "IVs with types different from the canonical IV should " 6594d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman "already have been handled!"); 6604d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman return CanonicalIV; 6614d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman } 6624d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman 66336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // Create and insert the PHI node for the induction variable in the 66436f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // specified loop. 66536f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman BasicBlock *Header = L->getHeader(); 666267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock *Preheader = L->getLoopPreheader(); 667051a950000e21935165db56695e35bade668193bGabor Greif PHINode *PN = PHINode::Create(Ty, "indvar", Header->begin()); 668cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(PN); 669a7235ea7245028a0723e8ab7fd011386b3900777Owen Anderson PN->addIncoming(Constant::getNullValue(Ty), Preheader); 67036f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 67136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman pred_iterator HPI = pred_begin(Header); 67236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman assert(HPI != pred_end(Header) && "Loop with zero preds???"); 67336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman if (!L->contains(*HPI)) ++HPI; 67436f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman assert(HPI != pred_end(Header) && L->contains(*HPI) && 67536f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman "No backedge in loop?"); 67636f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 67736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // Insert a unit add instruction right before the terminator corresponding 67836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // to the back-edge. 679eed707b1e6097aac2bb6b3d47271f6300ace7f2eOwen Anderson Constant *One = ConstantInt::get(Ty, 1); 6807cbd8a3e92221437048b484d5ef9c0a22d0f8c58Gabor Greif Instruction *Add = BinaryOperator::CreateAdd(PN, One, "indvar.next", 68136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman (*HPI)->getTerminator()); 682cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(Add); 68336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 68436f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman pred_iterator PI = pred_begin(Header); 685267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (*PI == Preheader) 68636f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman ++PI; 68736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman PN->addIncoming(Add, *PI); 68836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman return PN; 68936f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman } 69036f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 6914d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // {0,+,F} --> {0,+,1} * F 69236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // Get the canonical induction variable I for this loop. 6934d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman Value *I = CanonicalIV ? 6944d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman CanonicalIV : 6954d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman getOrInsertCanonicalInductionVariable(L, Ty); 69636f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 697df14a04b5ccbbe6a46c2ccb93e27b12a36ff163eChris Lattner // If this is a simple linear addrec, emit it now as a special case. 69840a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (S->isAffine()) // {0,+,F} --> i*F 69940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return 70040a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman expand(SE.getTruncateOrNoop( 70140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman SE.getMulExpr(SE.getUnknown(I), 70240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman SE.getNoopOrAnyExtend(S->getOperand(1), 70340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman I->getType())), 70440a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman Ty)); 70536f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 70636f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // If this is a chain of recurrences, turn it into a closed form, using the 70736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // folders, then expandCodeFor the closed form. This allows the folders to 70836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // simplify the expression without having to build a bunch of special code 70936f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // into this folder. 7100bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *IH = SE.getUnknown(I); // Get I as a "symbolic" SCEV. 71136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 7124d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // Promote S up to the canonical IV type, if the cast is foldable. 7130bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *NewS = S; 7140bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *Ext = SE.getNoopOrAnyExtend(S, I->getType()); 7154d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (isa<SCEVAddRecExpr>(Ext)) 7164d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman NewS = Ext; 7174d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman 7180bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *V = cast<SCEVAddRecExpr>(NewS)->evaluateAtIteration(IH, SE); 719e81561909d128c6e2d8033cb5465a49b2596b26aBill Wendling //cerr << "Evaluated: " << *this << "\n to: " << *V << "\n"; 72036f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 7214d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // Truncate the result down to the original type, if needed. 7220bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *T = SE.getTruncateOrNoop(V, Ty); 723469f3cdc13851914f3a766cbd8f701cf8431cacaDan Gohman return expand(T); 72436f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman} 72596fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov 726890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitTruncateExpr(const SCEVTruncateExpr *S) { 727af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 72892fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *V = expandCodeFor(S->getOperand(), 72992fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman SE.getEffectiveSCEVType(S->getOperand()->getType())); 730267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *I = Builder.CreateTrunc(V, Ty, "tmp"); 731cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(I); 732cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return I; 73311f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 73411f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 735890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitZeroExtendExpr(const SCEVZeroExtendExpr *S) { 736af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 73792fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *V = expandCodeFor(S->getOperand(), 73892fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman SE.getEffectiveSCEVType(S->getOperand()->getType())); 739267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *I = Builder.CreateZExt(V, Ty, "tmp"); 740cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(I); 741cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return I; 74211f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 74311f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 744890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitSignExtendExpr(const SCEVSignExtendExpr *S) { 745af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman const Type *Ty = SE.getEffectiveSCEVType(S->getType()); 74692fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *V = expandCodeFor(S->getOperand(), 74792fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman SE.getEffectiveSCEVType(S->getOperand()->getType())); 748267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *I = Builder.CreateSExt(V, Ty, "tmp"); 749cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(I); 750cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return I; 75111f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 75211f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 753890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitSMaxExpr(const SCEVSMaxExpr *S) { 7540196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Value *LHS = expand(S->getOperand(S->getNumOperands()-1)); 7550196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman const Type *Ty = LHS->getType(); 7560196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman for (int i = S->getNumOperands()-2; i >= 0; --i) { 7570196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, do the 7580196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // rest of the comparisons as integer. 7590196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (S->getOperand(i)->getType() != Ty) { 7600196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Ty = SE.getEffectiveSCEVType(Ty); 7610196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, Ty); 7620196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman } 76392fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *RHS = expandCodeFor(S->getOperand(i), Ty); 764267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *ICmp = Builder.CreateICmpSGT(LHS, RHS, "tmp"); 765cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(ICmp); 766267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *Sel = Builder.CreateSelect(ICmp, LHS, RHS, "smax"); 767cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(Sel); 768cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman LHS = Sel; 769c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky } 7700196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, cast the 7710196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // final result back to the pointer type. 7720196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (LHS->getType() != S->getType()) 7730196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, S->getType()); 774c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky return LHS; 775c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky} 776c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky 777890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitUMaxExpr(const SCEVUMaxExpr *S) { 7780196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Value *LHS = expand(S->getOperand(S->getNumOperands()-1)); 7790196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman const Type *Ty = LHS->getType(); 7800196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman for (int i = S->getNumOperands()-2; i >= 0; --i) { 7810196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, do the 7820196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // rest of the comparisons as integer. 7830196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (S->getOperand(i)->getType() != Ty) { 7840196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Ty = SE.getEffectiveSCEVType(Ty); 7850196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, Ty); 7860196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman } 78792fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *RHS = expandCodeFor(S->getOperand(i), Ty); 788267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *ICmp = Builder.CreateICmpUGT(LHS, RHS, "tmp"); 789cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(ICmp); 790267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *Sel = Builder.CreateSelect(ICmp, LHS, RHS, "umax"); 791cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman InsertedValues.insert(Sel); 792cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman LHS = Sel; 7933e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky } 7940196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, cast the 7950196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // final result back to the pointer type. 7960196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (LHS->getType() != S->getType()) 7970196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, S->getType()); 7983e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky return LHS; 7993e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky} 8003e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky 801c40f17b08774c2dcc5787fd83241e3c64ba82974Dan GohmanValue *SCEVExpander::visitFieldOffsetExpr(const SCEVFieldOffsetExpr *S) { 802c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return ConstantExpr::getOffsetOf(S->getStructType(), S->getFieldNo()); 803c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman} 804c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 805c40f17b08774c2dcc5787fd83241e3c64ba82974Dan GohmanValue *SCEVExpander::visitAllocSizeExpr(const SCEVAllocSizeExpr *S) { 806c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return ConstantExpr::getSizeOf(S->getAllocType()); 807c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman} 808c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 8090bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan GohmanValue *SCEVExpander::expandCodeFor(const SCEV *SH, const Type *Ty) { 81011f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman // Expand the code for this SCEV. 8112d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman Value *V = expand(SH); 8125be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (Ty) { 8135be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman assert(SE.getTypeSizeInBits(Ty) == SE.getTypeSizeInBits(SH->getType()) && 8145be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman "non-trivial casts should be done with the SCEVs directly!"); 8155be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman V = InsertNoopCastOfTo(V, Ty); 8165be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 8175be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return V; 81811f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 81911f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 820890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::expand(const SCEV *S) { 82140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // Compute an insertion point for this SCEV object. Hoist the instructions 82240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // as far out in the loop nest as possible. 823267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction *InsertPt = Builder.GetInsertPoint(); 824267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman for (Loop *L = SE.LI->getLoopFor(Builder.GetInsertBlock()); ; 82540a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman L = L->getParentLoop()) 82640a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (S->isLoopInvariant(L)) { 82740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (!L) break; 82840a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (BasicBlock *Preheader = L->getLoopPreheader()) 82940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman InsertPt = Preheader->getTerminator(); 83040a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman } else { 83140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // If the SCEV is computable at this level, insert it into the header 83240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // after the PHIs (and after any other instructions that we've inserted 83340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // there) so that it is guaranteed to dominate any user inside the loop. 83440a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (L && S->hasComputableLoopEvolution(L)) 83540a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman InsertPt = L->getHeader()->getFirstNonPHI(); 836267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman while (isInsertedInstruction(InsertPt)) 837267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman InsertPt = next(BasicBlock::iterator(InsertPt)); 83840a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman break; 83940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman } 84040a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman 841667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman // Check to see if we already expanded this here. 842667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman std::map<std::pair<const SCEV *, Instruction *>, 843667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman AssertingVH<Value> >::iterator I = 844667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman InsertedExpressions.find(std::make_pair(S, InsertPt)); 845267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (I != InsertedExpressions.end()) 846667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman return I->second; 847267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman 848267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 849267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 850267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Builder.SetInsertPoint(InsertPt->getParent(), InsertPt); 851667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman 852667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman // Expand the expression into instructions. 85396fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov Value *V = visit(S); 85440a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman 855667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman // Remember the expanded value for this SCEV at this location. 856667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman InsertedExpressions[std::make_pair(S, InsertPt)] = V; 857667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman 858267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Builder.SetInsertPoint(SaveInsertBB, SaveInsertPt); 85996fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov return V; 86096fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov} 8611d09de3eca23267855e28297fcb40de3632ea47bDan Gohman 8621d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// getOrInsertCanonicalInductionVariable - This method returns the 8631d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// canonical induction variable of the specified type for the specified 8641d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// loop (inserting one if there is none). A canonical induction variable 8651d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// starts at zero and steps by one on each iteration. 8661d09de3eca23267855e28297fcb40de3632ea47bDan GohmanValue * 8671d09de3eca23267855e28297fcb40de3632ea47bDan GohmanSCEVExpander::getOrInsertCanonicalInductionVariable(const Loop *L, 8681d09de3eca23267855e28297fcb40de3632ea47bDan Gohman const Type *Ty) { 8691d09de3eca23267855e28297fcb40de3632ea47bDan Gohman assert(Ty->isInteger() && "Can only insert integer induction variables!"); 8700bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *H = SE.getAddRecExpr(SE.getIntegerSCEV(0, Ty), 87140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman SE.getIntegerSCEV(1, Ty), L); 872267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 873267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 87440a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman Value *V = expandCodeFor(H, 0, L->getHeader()->begin()); 875267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (SaveInsertBB) 876267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Builder.SetInsertPoint(SaveInsertBB, SaveInsertPt); 87740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return V; 8781d09de3eca23267855e28297fcb40de3632ea47bDan Gohman} 879