ScalarEvolutionExpander.cpp revision 0a2a60ace9b79164b71794ce7ff981171c61e442
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" 22d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick 2336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begemanusing namespace llvm; 2436f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 2519e5ada58a8a07d3d6d67312550f6d0791d84c3cGabor Greif/// ReuseOrCreateCast - Arrange for there to be a cast of V to Ty at IP, 26485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman/// reusing an existing cast if a suitable one exists, moving an existing 27485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman/// cast if a suitable one exists but isn't in the right place, or 2819e5ada58a8a07d3d6d67312550f6d0791d84c3cGabor Greif/// creating a new one. 29db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris LattnerValue *SCEVExpander::ReuseOrCreateCast(Value *V, Type *Ty, 30485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman Instruction::CastOps Op, 31485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman BasicBlock::iterator IP) { 32485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman // Check to see if there is already a cast! 33485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman for (Value::use_iterator UI = V->use_begin(), E = V->use_end(); 34f64f9cf7ec39ae91bca84dc6ad3c8fc3343b358aGabor Greif UI != E; ++UI) { 35f64f9cf7ec39ae91bca84dc6ad3c8fc3343b358aGabor Greif User *U = *UI; 36f64f9cf7ec39ae91bca84dc6ad3c8fc3343b358aGabor Greif if (U->getType() == Ty) 3719e5ada58a8a07d3d6d67312550f6d0791d84c3cGabor Greif if (CastInst *CI = dyn_cast<CastInst>(U)) 38485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman if (CI->getOpcode() == Op) { 39485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman // If the cast isn't where we want it, fix it. 40485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman if (BasicBlock::iterator(CI) != IP) { 41485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman // Create a new cast, and leave the old cast in place in case 42485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman // it is being used as an insert point. Clear its operand 43485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman // so that it doesn't hold anything live. 44485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman Instruction *NewCI = CastInst::Create(Op, V, Ty, "", IP); 45485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman NewCI->takeName(CI); 46485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman CI->replaceAllUsesWith(NewCI); 47485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman CI->setOperand(0, UndefValue::get(V->getType())); 48485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman rememberInstruction(NewCI); 49485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman return NewCI; 50485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman } 516f5fed253f58645bf45448893a585ffbd9914989Dan Gohman rememberInstruction(CI); 52485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman return CI; 53485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman } 54f64f9cf7ec39ae91bca84dc6ad3c8fc3343b358aGabor Greif } 55485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman 56485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman // Create a new cast. 57485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman Instruction *I = CastInst::Create(Op, V, Ty, V->getName(), IP); 58485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman rememberInstruction(I); 59485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman return I; 60485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman} 61485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman 62267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman/// InsertNoopCastOfTo - Insert a cast of V to the specified type, 63267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman/// which must be possible with a noop cast, doing what we can to share 64267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman/// the casts. 65db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris LattnerValue *SCEVExpander::InsertNoopCastOfTo(Value *V, Type *Ty) { 66267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction::CastOps Op = CastInst::getCastOpcode(V, false, Ty, false); 67267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman assert((Op == Instruction::BitCast || 68267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Op == Instruction::PtrToInt || 69267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Op == Instruction::IntToPtr) && 70267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman "InsertNoopCastOfTo cannot perform non-noop casts!"); 71267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman assert(SE.getTypeSizeInBits(V->getType()) == SE.getTypeSizeInBits(Ty) && 72267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman "InsertNoopCastOfTo cannot change sizes!"); 73267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman 742d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman // Short-circuit unnecessary bitcasts. 75267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (Op == Instruction::BitCast && V->getType() == Ty) 762d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman return V; 772d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman 78f04fa483b83227c570bc58e1684ea096430a6697Dan Gohman // Short-circuit unnecessary inttoptr<->ptrtoint casts. 79267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if ((Op == Instruction::PtrToInt || Op == Instruction::IntToPtr) && 8080dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman SE.getTypeSizeInBits(Ty) == SE.getTypeSizeInBits(V->getType())) { 81af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman if (CastInst *CI = dyn_cast<CastInst>(V)) 82af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman if ((CI->getOpcode() == Instruction::PtrToInt || 83af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman CI->getOpcode() == Instruction::IntToPtr) && 84af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman SE.getTypeSizeInBits(CI->getType()) == 85af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman SE.getTypeSizeInBits(CI->getOperand(0)->getType())) 86af79fb5f47b0088c6a8973a7fdbaea96973a429dDan Gohman return CI->getOperand(0); 8780dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) 8880dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman if ((CE->getOpcode() == Instruction::PtrToInt || 8980dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman CE->getOpcode() == Instruction::IntToPtr) && 9080dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman SE.getTypeSizeInBits(CE->getType()) == 9180dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman SE.getTypeSizeInBits(CE->getOperand(0)->getType())) 9280dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman return CE->getOperand(0); 9380dcdee0f48820ecea86c15768324945bb0d68d1Dan Gohman } 94f04fa483b83227c570bc58e1684ea096430a6697Dan Gohman 95485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman // Fold a cast of a constant. 96ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if (Constant *C = dyn_cast<Constant>(V)) 97baf3c404409d5e47b13984a7f95bfbd6d1f2e79eOwen Anderson return ConstantExpr::getCast(Op, C, Ty); 984c0d5d5db876b0628bdf6a2174263a1c0a9130e2Dan Gohman 99485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman // Cast the argument at the beginning of the entry block, after 100485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman // any bitcasts of other arguments. 101ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if (Argument *A = dyn_cast<Argument>(V)) { 102485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman BasicBlock::iterator IP = A->getParent()->getEntryBlock().begin(); 103485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman while ((isa<BitCastInst>(IP) && 104485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman isa<Argument>(cast<BitCastInst>(IP)->getOperand(0)) && 105485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman cast<BitCastInst>(IP)->getOperand(0) != A) || 106485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman isa<DbgInfoIntrinsic>(IP)) 107485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman ++IP; 108485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman return ReuseOrCreateCast(A, Ty, Op, IP); 109ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner } 1103913187bf6135e6a71260c65eed664095c8f9ce9Wojciech Matyjewicz 111485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman // Cast the instruction immediately after the instruction. 112ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner Instruction *I = cast<Instruction>(V); 113ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner BasicBlock::iterator IP = I; ++IP; 114ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner if (InvokeInst *II = dyn_cast<InvokeInst>(I)) 115ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner IP = II->getNormalDest()->begin(); 11608f55d02da2cd24f3b4297259ef6429b8bf1ef97Jim Grosbach while (isa<PHINode>(IP) || isa<DbgInfoIntrinsic>(IP)) ++IP; 117485c43fc478d5e16c55e14cb2586b56cc1c4c91fDan Gohman return ReuseOrCreateCast(I, Ty, Op, IP); 118ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner} 119ca1a4bebb3928ba18fb8751e2f0c0f88fad54cfdChris Lattner 1207fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner/// InsertBinop - Insert the specified binary operator, doing a small amount 1217fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner/// of work to avoid inserting an obviously redundant operation. 122267a385342f2e7388f178b327dd87c5f29afd51bDan GohmanValue *SCEVExpander::InsertBinop(Instruction::BinaryOps Opcode, 123267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *LHS, Value *RHS) { 1240f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman // Fold a binop with constant operands. 1250f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman if (Constant *CLHS = dyn_cast<Constant>(LHS)) 1260f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman if (Constant *CRHS = dyn_cast<Constant>(RHS)) 127baf3c404409d5e47b13984a7f95bfbd6d1f2e79eOwen Anderson return ConstantExpr::get(Opcode, CLHS, CRHS); 1280f0eb18addc94bf3d8179fbce162c8c4622b9866Dan Gohman 1297fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner // Do a quick scan to see if we have this binop nearby. If so, reuse it. 1307fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner unsigned ScanLimit = 6; 131267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator BlockBegin = Builder.GetInsertBlock()->begin(); 132267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman // Scanning starts from the last instruction before the insertion point. 133267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator IP = Builder.GetInsertPoint(); 134267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (IP != BlockBegin) { 1358a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz --IP; 1368a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz for (; ScanLimit; --IP, --ScanLimit) { 1378d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen // Don't count dbg.value against the ScanLimit, to avoid perturbing the 1388d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen // generated code. 1398d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen if (isa<DbgInfoIntrinsic>(IP)) 1408d50ea760322630dbb9ab6436ca356b279adee10Dale Johannesen ScanLimit++; 1415be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (IP->getOpcode() == (unsigned)Opcode && IP->getOperand(0) == LHS && 1425be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman IP->getOperand(1) == RHS) 1435be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return IP; 1448a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz if (IP == BlockBegin) break; 1458a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz } 1467fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner } 147267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman 148087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Save the original insertion point so we can restore it when we're done. 149087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 150087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 151087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 152087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Move the insertion point out of as many loops as we can. 153087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman while (const Loop *L = SE.LI->getLoopFor(Builder.GetInsertBlock())) { 154087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!L->isLoopInvariant(LHS) || !L->isLoopInvariant(RHS)) break; 155087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman BasicBlock *Preheader = L->getLoopPreheader(); 156087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!Preheader) break; 157087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 158087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Ok, move up a level. 159087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Builder.SetInsertPoint(Preheader, Preheader->getTerminator()); 160087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } 161087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 1628a08769bad43a22fae2845bb0ba0fd1266cd55c8Wojciech Matyjewicz // If we haven't found this binop, insert it. 163df3ad6697bb849e514c0881ca8700ea36678cbdaDevang Patel Instruction *BO = cast<Instruction>(Builder.CreateBinOp(Opcode, LHS, RHS, "tmp")); 164df3ad6697bb849e514c0881ca8700ea36678cbdaDevang Patel BO->setDebugLoc(SaveInsertPt->getDebugLoc()); 165a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(BO); 166087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 167087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Restore the original insert point. 168087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (SaveInsertBB) 169087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 170087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 171cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return BO; 1727fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner} 1737fec90ebf4ebe7aa73a6dd7d275c255587c041adChris Lattner 1744a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman/// FactorOutConstant - Test if S is divisible by Factor, using signed 175453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// division. If so, update S with Factor divided out and return true. 1763f46a3abeedba8d517b4182de34c821d752db058Dan Gohman/// S need not be evenly divisible if a reasonable remainder can be 1774a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman/// computed. 178453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// TODO: When ScalarEvolution gets a SCEVSDivExpr, this can be made 179453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// unnecessary; in its place, just signed-divide Ops[i] by the scale and 180453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// check to see if the divide was folded. 1810bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohmanstatic bool FactorOutConstant(const SCEV *&S, 1820bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *&Remainder, 183c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Factor, 184c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ScalarEvolution &SE, 185c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const TargetData *TD) { 186453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // Everything is divisible by one. 187c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (Factor->isOne()) 188c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 189c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 190c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // x/x == 1. 191c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (S == Factor) { 192deff621abdd48bd70434bd4d7ef30f08ddba1cd8Dan Gohman S = SE.getConstant(S->getType(), 1); 193453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return true; 194c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 195453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 196453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // For a Constant, check for a multiple of the given factor. 1974a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman if (const SCEVConstant *C = dyn_cast<SCEVConstant>(S)) { 198c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // 0/x == 0. 199c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (C->isZero()) 200453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return true; 201c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Check for divisibility. 202c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVConstant *FC = dyn_cast<SCEVConstant>(Factor)) { 203c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ConstantInt *CI = 204c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ConstantInt::get(SE.getContext(), 205c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman C->getValue()->getValue().sdiv( 206c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FC->getValue()->getValue())); 207c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If the quotient is zero and the remainder is non-zero, reject 208c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // the value at this scale. It will be considered for subsequent 209c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // smaller scales. 210c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!CI->isZero()) { 211c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Div = SE.getConstant(CI); 212c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman S = Div; 213c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Remainder = 214c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getAddExpr(Remainder, 215c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getConstant(C->getValue()->getValue().srem( 216c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FC->getValue()->getValue()))); 217c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 218c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 219453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 2204a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman } 221453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 222453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // In a Mul, check if there is a constant operand which is a multiple 223453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // of the given factor. 224c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVMulExpr *M = dyn_cast<SCEVMulExpr>(S)) { 225c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (TD) { 226c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // With TargetData, the size is known. Check if there is a constant 227c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // operand which is a multiple of the given factor. If so, we can 228c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // factor it. 229c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEVConstant *FC = cast<SCEVConstant>(Factor); 230c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVConstant *C = dyn_cast<SCEVConstant>(M->getOperand(0))) 231c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!C->getValue()->getValue().srem(FC->getValue()->getValue())) { 232f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman SmallVector<const SCEV *, 4> NewMulOps(M->op_begin(), M->op_end()); 233c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman NewMulOps[0] = 234c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getConstant(C->getValue()->getValue().sdiv( 235c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman FC->getValue()->getValue())); 236c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman S = SE.getMulExpr(NewMulOps); 237c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 238c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 239c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } else { 240c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Without TargetData, check if Factor can be factored out of any of the 241c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Mul's operands. If so, we can just remove it. 242c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = 0, e = M->getNumOperands(); i != e; ++i) { 243c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *SOp = M->getOperand(i); 244deff621abdd48bd70434bd4d7ef30f08ddba1cd8Dan Gohman const SCEV *Remainder = SE.getConstant(SOp->getType(), 0); 245c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (FactorOutConstant(SOp, Remainder, Factor, SE, TD) && 246c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Remainder->isZero()) { 247f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman SmallVector<const SCEV *, 4> NewMulOps(M->op_begin(), M->op_end()); 248c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman NewMulOps[i] = SOp; 249c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman S = SE.getMulExpr(NewMulOps); 250c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return true; 251c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 252453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 253c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 254c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 255453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 256453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // In an AddRec, check if both start and step are divisible. 257453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman if (const SCEVAddRecExpr *A = dyn_cast<SCEVAddRecExpr>(S)) { 2580bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *Step = A->getStepRecurrence(SE); 259deff621abdd48bd70434bd4d7ef30f08ddba1cd8Dan Gohman const SCEV *StepRem = SE.getConstant(Step->getType(), 0); 260c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!FactorOutConstant(Step, StepRem, Factor, SE, TD)) 2614a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman return false; 2624a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman if (!StepRem->isZero()) 2634a4f767235dac50965fc266fb822d9a2e37d5212Dan Gohman return false; 2640bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *Start = A->getStart(); 265c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!FactorOutConstant(Start, Remainder, Factor, SE, TD)) 266453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return false; 2673228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick // FIXME: can use A->getNoWrapFlags(FlagNW) 2683228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick S = SE.getAddRecExpr(Start, Step, A->getLoop(), SCEV::FlagAnyWrap); 269453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return true; 270453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 271453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 272453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman return false; 273453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman} 274453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 275c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// SimplifyAddOperands - Sort and simplify a list of add operands. NumAddRecs 276c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// is the number of SCEVAddRecExprs present, which are kept at the end of 277c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// the list. 278c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// 279c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohmanstatic void SimplifyAddOperands(SmallVectorImpl<const SCEV *> &Ops, 280db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty, 281c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ScalarEvolution &SE) { 282c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman unsigned NumAddRecs = 0; 283c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = Ops.size(); i > 0 && isa<SCEVAddRecExpr>(Ops[i-1]); --i) 284c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ++NumAddRecs; 285c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Group Ops into non-addrecs and addrecs. 286c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 8> NoAddRecs(Ops.begin(), Ops.end() - NumAddRecs); 287c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 8> AddRecs(Ops.end() - NumAddRecs, Ops.end()); 288c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Let ScalarEvolution sort and simplify the non-addrecs list. 289c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Sum = NoAddRecs.empty() ? 290deff621abdd48bd70434bd4d7ef30f08ddba1cd8Dan Gohman SE.getConstant(Ty, 0) : 291c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SE.getAddExpr(NoAddRecs); 292c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If it returned an add, use the operands. Otherwise it simplified 293c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // the sum into a single value, so just use that. 294f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman Ops.clear(); 295c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(Sum)) 296403a8cdda5e76ea689693de16474650b4b0df818Dan Gohman Ops.append(Add->op_begin(), Add->op_end()); 297f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman else if (!Sum->isZero()) 298f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman Ops.push_back(Sum); 299c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Then append the addrecs. 300403a8cdda5e76ea689693de16474650b4b0df818Dan Gohman Ops.append(AddRecs.begin(), AddRecs.end()); 301c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman} 302c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman 303c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// SplitAddRecs - Flatten a list of add operands, moving addrec start values 304c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// out to the top level. For example, convert {a + b,+,c} to a, b, {0,+,d}. 305c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// This helps expose more opportunities for folding parts of the expressions 306c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// into GEP indices. 307c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman/// 308c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohmanstatic void SplitAddRecs(SmallVectorImpl<const SCEV *> &Ops, 309db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty, 310c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ScalarEvolution &SE) { 311c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Find the addrecs. 312c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman SmallVector<const SCEV *, 8> AddRecs; 313c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman for (unsigned i = 0, e = Ops.size(); i != e; ++i) 314c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman while (const SCEVAddRecExpr *A = dyn_cast<SCEVAddRecExpr>(Ops[i])) { 315c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Start = A->getStart(); 316c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (Start->isZero()) break; 317deff621abdd48bd70434bd4d7ef30f08ddba1cd8Dan Gohman const SCEV *Zero = SE.getConstant(Ty, 0); 318c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman AddRecs.push_back(SE.getAddRecExpr(Zero, 319c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman A->getStepRecurrence(SE), 3203228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick A->getLoop(), 3213228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick // FIXME: A->getNoWrapFlags(FlagNW) 3223228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick SCEV::FlagAnyWrap)); 323c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(Start)) { 324c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Ops[i] = Zero; 325403a8cdda5e76ea689693de16474650b4b0df818Dan Gohman Ops.append(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. 333403a8cdda5e76ea689693de16474650b4b0df818Dan Gohman Ops.append(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, 368db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner PointerType *PTy, 369db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty, 3705be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman Value *V) { 371db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner 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]; 395deff621abdd48bd70434bd4d7ef30f08ddba1cd8Dan Gohman const SCEV *Remainder = SE.getConstant(Ty, 0); 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. 426db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner while (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])) { 454db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner 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 477db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (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)) 497dab3d29605a5c83db41b28176273ef55961120c1Jay Foad return ConstantExpr::getGetElementPtr(CLHS, CRHS); 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, 5750a2a60ace9b79164b71794ce7ff981171c61e442Jay Foad GepIndices, 576267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman "scevgep"); 5775be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman Ops.push_back(SE.getUnknown(GEP)); 578a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(GEP); 579087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 580087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Restore the original insert point. 581087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (SaveInsertBB) 582087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 583087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 5845be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return expand(SE.getAddExpr(Ops)); 5855be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman} 5865be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 587a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman/// isNonConstantNegative - Return true if the specified scev is negated, but 588a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman/// not a constant. 589a10756ee657a4d43a48cca5c166919093930ed6bDan Gohmanstatic bool isNonConstantNegative(const SCEV *F) { 590a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEVMulExpr *Mul = dyn_cast<SCEVMulExpr>(F); 591a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!Mul) return false; 592a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 593a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // If there is a constant factor, it will be first. 594a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEVConstant *SC = dyn_cast<SCEVConstant>(Mul->getOperand(0)); 595a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!SC) return false; 596a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 597a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Return true if the value is negative, this matches things like (-42 * V). 598a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman return SC->getValue()->getValue().isNegative(); 599a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman} 600a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 601087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman/// PickMostRelevantLoop - Given two loops pick the one that's most relevant for 602087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman/// SCEV expansion. If they are nested, this is the most nested. If they are 603087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman/// neighboring, pick the later. 604087bd1e3a12893873761736bf0f905a350e9e708Dan Gohmanstatic const Loop *PickMostRelevantLoop(const Loop *A, const Loop *B, 605087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman DominatorTree &DT) { 606087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!A) return B; 607087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!B) return A; 608087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (A->contains(B)) return B; 609087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (B->contains(A)) return A; 610087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (DT.dominates(A->getHeader(), B->getHeader())) return B; 611087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (DT.dominates(B->getHeader(), A->getHeader())) return A; 612087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return A; // Arbitrarily break the tie. 613087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman} 614087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 6159c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman/// getRelevantLoop - Get the most relevant loop associated with the given 616087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman/// expression, according to PickMostRelevantLoop. 6179c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohmanconst Loop *SCEVExpander::getRelevantLoop(const SCEV *S) { 6189c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman // Test whether we've already computed the most relevant loop for this SCEV. 6199c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman std::pair<DenseMap<const SCEV *, const Loop *>::iterator, bool> Pair = 6209c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman RelevantLoops.insert(std::make_pair(S, static_cast<const Loop *>(0))); 6219c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman if (!Pair.second) 6229c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman return Pair.first->second; 6239c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman 624087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (isa<SCEVConstant>(S)) 6259c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman // A constant has no relevant loops. 626087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return 0; 627087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (const SCEVUnknown *U = dyn_cast<SCEVUnknown>(S)) { 628087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (const Instruction *I = dyn_cast<Instruction>(U->getValue())) 6299c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman return Pair.first->second = SE.LI->getLoopFor(I->getParent()); 6309c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman // A non-instruction has no relevant loops. 631087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return 0; 632087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } 633087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (const SCEVNAryExpr *N = dyn_cast<SCEVNAryExpr>(S)) { 634087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman const Loop *L = 0; 635087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(S)) 636087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman L = AR->getLoop(); 637087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (SCEVNAryExpr::op_iterator I = N->op_begin(), E = N->op_end(); 638087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman I != E; ++I) 6399c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman L = PickMostRelevantLoop(L, getRelevantLoop(*I), *SE.DT); 6409c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman return RelevantLoops[N] = L; 6419c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman } 6429c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman if (const SCEVCastExpr *C = dyn_cast<SCEVCastExpr>(S)) { 6439c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman const Loop *Result = getRelevantLoop(C->getOperand()); 6449c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman return RelevantLoops[C] = Result; 6459c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman } 6469c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman if (const SCEVUDivExpr *D = dyn_cast<SCEVUDivExpr>(S)) { 6479c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman const Loop *Result = 6489c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman PickMostRelevantLoop(getRelevantLoop(D->getLHS()), 6499c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman getRelevantLoop(D->getRHS()), 6509c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman *SE.DT); 6519c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman return RelevantLoops[D] = Result; 652087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } 653087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman llvm_unreachable("Unexpected SCEV type!"); 6549c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman return 0; 655087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman} 656c4f7ec85ecb760fff2b702c6deb06506b968ba4fDan Gohman 657b35798347ea87b8b6d36155b211016a7769f01abDan Gohmannamespace { 658b35798347ea87b8b6d36155b211016a7769f01abDan Gohman 659087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman/// LoopCompare - Compare loops by PickMostRelevantLoop. 660087bd1e3a12893873761736bf0f905a350e9e708Dan Gohmanclass LoopCompare { 661087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman DominatorTree &DT; 662087bd1e3a12893873761736bf0f905a350e9e708Dan Gohmanpublic: 663087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman explicit LoopCompare(DominatorTree &dt) : DT(dt) {} 664087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 665087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman bool operator()(std::pair<const Loop *, const SCEV *> LHS, 666087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman std::pair<const Loop *, const SCEV *> RHS) const { 667bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman // Keep pointer operands sorted at the end. 668bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman if (LHS.second->getType()->isPointerTy() != 669bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman RHS.second->getType()->isPointerTy()) 670bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman return LHS.second->getType()->isPointerTy(); 671bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman 672087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Compare loops with PickMostRelevantLoop. 673087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (LHS.first != RHS.first) 674087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return PickMostRelevantLoop(LHS.first, RHS.first, DT) != LHS.first; 675087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 676087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // If one operand is a non-constant negative and the other is not, 677087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // put the non-constant negative on the right so that a sub can 678087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // be used instead of a negate and add. 679087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (isNonConstantNegative(LHS.second)) { 680087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!isNonConstantNegative(RHS.second)) 681087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return false; 682087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } else if (isNonConstantNegative(RHS.second)) 683087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return true; 684087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 685087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Otherwise they are equivalent according to this comparison. 686087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return false; 687c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman } 688087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman}; 6895be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 690b35798347ea87b8b6d36155b211016a7769f01abDan Gohman} 691b35798347ea87b8b6d36155b211016a7769f01abDan Gohman 692087bd1e3a12893873761736bf0f905a350e9e708Dan GohmanValue *SCEVExpander::visitAddExpr(const SCEVAddExpr *S) { 693db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty = SE.getEffectiveSCEVType(S->getType()); 694e24fa64d52330626553298f56ba5aa702624c282Dan Gohman 695087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Collect all the add operands in a loop, along with their associated loops. 696087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Iterate in reverse so that constants are emitted last, all else equal, and 697087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // so that pointer operands are inserted first, which the code below relies on 698087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // to form more involved GEPs. 699087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman SmallVector<std::pair<const Loop *, const SCEV *>, 8> OpsAndLoops; 700087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (std::reverse_iterator<SCEVAddExpr::op_iterator> I(S->op_end()), 701087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman E(S->op_begin()); I != E; ++I) 7029c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman OpsAndLoops.push_back(std::make_pair(getRelevantLoop(*I), *I)); 703087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 704087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Sort by loop. Use a stable sort so that constants follow non-constants and 705087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // pointer operands precede non-pointer operands. 706087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman std::stable_sort(OpsAndLoops.begin(), OpsAndLoops.end(), LoopCompare(*SE.DT)); 707087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 708087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Emit instructions to add all the operands. Hoist as much as possible 709087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // out of loops, and form meaningful getelementptrs where possible. 710087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Value *Sum = 0; 711087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (SmallVectorImpl<std::pair<const Loop *, const SCEV *> >::iterator 712087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman I = OpsAndLoops.begin(), E = OpsAndLoops.end(); I != E; ) { 713087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman const Loop *CurLoop = I->first; 714087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman const SCEV *Op = I->second; 715087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!Sum) { 716087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // This is the first operand. Just expand it. 717087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = expand(Op); 718087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 719db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner } else if (PointerType *PTy = dyn_cast<PointerType>(Sum->getType())) { 720087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // The running sum expression is a pointer. Try to form a getelementptr 721087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // at this level with that as the base. 722087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman SmallVector<const SCEV *, 4> NewOps; 723bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman for (; I != E && I->first == CurLoop; ++I) { 724bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman // If the operand is SCEVUnknown and not instructions, peek through 725bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman // it, to enable more of it to be folded into the GEP. 726bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman const SCEV *X = I->second; 727bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman if (const SCEVUnknown *U = dyn_cast<SCEVUnknown>(X)) 728bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman if (!isa<Instruction>(U->getValue())) 729bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman X = SE.getSCEV(U->getValue()); 730bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman NewOps.push_back(X); 731bb5d92741b2835eff25e4524bc6a5b0fb4fda855Dan Gohman } 732087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = expandAddToGEP(NewOps.begin(), NewOps.end(), PTy, Ty, Sum); 733db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner } else if (PointerType *PTy = dyn_cast<PointerType>(Op->getType())) { 734087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // The running sum is an integer, and there's a pointer at this level. 735f8d0578e4cbd5922696c92f5068c5513d8e8d60eDan Gohman // Try to form a getelementptr. If the running sum is instructions, 736f8d0578e4cbd5922696c92f5068c5513d8e8d60eDan Gohman // use a SCEVUnknown to avoid re-analyzing them. 737087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman SmallVector<const SCEV *, 4> NewOps; 738f8d0578e4cbd5922696c92f5068c5513d8e8d60eDan Gohman NewOps.push_back(isa<Instruction>(Sum) ? SE.getUnknown(Sum) : 739f8d0578e4cbd5922696c92f5068c5513d8e8d60eDan Gohman SE.getSCEV(Sum)); 740087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (++I; I != E && I->first == CurLoop; ++I) 741087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman NewOps.push_back(I->second); 742087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = expandAddToGEP(NewOps.begin(), NewOps.end(), PTy, Ty, expand(Op)); 743087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } else if (isNonConstantNegative(Op)) { 744087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Instead of doing a negate and add, just do a subtract. 745a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *W = expandCodeFor(SE.getNegativeSCEV(Op), Ty); 746087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = InsertNoopCastOfTo(Sum, Ty); 747087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = InsertBinop(Instruction::Sub, Sum, W); 748087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 749a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } else { 750087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // A simple add. 751a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *W = expandCodeFor(Op, Ty); 752087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = InsertNoopCastOfTo(Sum, Ty); 753087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Canonicalize a constant to the RHS. 754087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (isa<Constant>(Sum)) std::swap(Sum, W); 755087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Sum = InsertBinop(Instruction::Add, Sum, W); 756087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 757a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 7582d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman } 759087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 760087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return Sum; 761e24fa64d52330626553298f56ba5aa702624c282Dan Gohman} 7625be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman 763890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitMulExpr(const SCEVMulExpr *S) { 764db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty = SE.getEffectiveSCEVType(S->getType()); 765087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 766087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Collect all the mul operands in a loop, along with their associated loops. 767087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Iterate in reverse so that constants are emitted last, all else equal. 768087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman SmallVector<std::pair<const Loop *, const SCEV *>, 8> OpsAndLoops; 769087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (std::reverse_iterator<SCEVMulExpr::op_iterator> I(S->op_end()), 770087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman E(S->op_begin()); I != E; ++I) 7719c9fcfc719158a46cb2e41b66d7dc1a63cd48d74Dan Gohman OpsAndLoops.push_back(std::make_pair(getRelevantLoop(*I), *I)); 772087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 773087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Sort by loop. Use a stable sort so that constants follow non-constants. 774087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman std::stable_sort(OpsAndLoops.begin(), OpsAndLoops.end(), LoopCompare(*SE.DT)); 775087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman 776087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Emit instructions to mul all the operands. Hoist as much as possible 777087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // out of loops. 778087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Value *Prod = 0; 779087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman for (SmallVectorImpl<std::pair<const Loop *, const SCEV *> >::iterator 780087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman I = OpsAndLoops.begin(), E = OpsAndLoops.end(); I != E; ) { 781087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman const SCEV *Op = I->second; 782087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (!Prod) { 783087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // This is the first operand. Just expand it. 784087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Prod = expand(Op); 785087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 786087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } else if (Op->isAllOnesValue()) { 787087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Instead of doing a multiply by negative one, just do a negate. 788087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Prod = InsertNoopCastOfTo(Prod, Ty); 789087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Prod = InsertBinop(Instruction::Sub, Constant::getNullValue(Ty), Prod); 790087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 791087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } else { 792087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // A simple mul. 793087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Value *W = expandCodeFor(Op, Ty); 794087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Prod = InsertNoopCastOfTo(Prod, Ty); 795087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman // Canonicalize a constant to the RHS. 796087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman if (isa<Constant>(Prod)) std::swap(Prod, W); 797087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman Prod = InsertBinop(Instruction::Mul, Prod, W); 798087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman ++I; 799087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman } 8002d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman } 8012d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman 802087bd1e3a12893873761736bf0f905a350e9e708Dan Gohman return Prod; 80336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman} 80436f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 805890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitUDivExpr(const SCEVUDivExpr *S) { 806db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty = SE.getEffectiveSCEVType(S->getType()); 8072d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman 80892fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *LHS = expandCodeFor(S->getLHS(), Ty); 809890f92b744fb074465bc2b7006ee753a181f62a4Dan Gohman if (const SCEVConstant *SC = dyn_cast<SCEVConstant>(S->getRHS())) { 8106177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky const APInt &RHS = SC->getValue()->getValue(); 8116177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky if (RHS.isPowerOf2()) 8126177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky return InsertBinop(Instruction::LShr, LHS, 813eed707b1e6097aac2bb6b3d47271f6300ace7f2eOwen Anderson ConstantInt::get(Ty, RHS.logBase2())); 8146177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky } 8156177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky 81692fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *RHS = expandCodeFor(S->getRHS(), Ty); 817267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman return InsertBinop(Instruction::UDiv, LHS, RHS); 8186177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky} 8196177fd4fcee4d82692c47e33754ffe285c38cc69Nick Lewycky 820453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// Move parts of Base into Rest to leave Base with the minimal 821453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// expression that provides a pointer operand suitable for a 822453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman/// GEP expansion. 8230bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohmanstatic void ExposePointerBase(const SCEV *&Base, const SCEV *&Rest, 824453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman ScalarEvolution &SE) { 825453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman while (const SCEVAddRecExpr *A = dyn_cast<SCEVAddRecExpr>(Base)) { 826453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Base = A->getStart(); 827453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Rest = SE.getAddExpr(Rest, 828deff621abdd48bd70434bd4d7ef30f08ddba1cd8Dan Gohman SE.getAddRecExpr(SE.getConstant(A->getType(), 0), 829453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman A->getStepRecurrence(SE), 8303228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick A->getLoop(), 8313228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick // FIXME: A->getNoWrapFlags(FlagNW) 8323228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick SCEV::FlagAnyWrap)); 833453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 834453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman if (const SCEVAddExpr *A = dyn_cast<SCEVAddExpr>(Base)) { 835453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Base = A->getOperand(A->getNumOperands()-1); 8360bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman SmallVector<const SCEV *, 8> NewAddOps(A->op_begin(), A->op_end()); 837453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman NewAddOps.back() = Rest; 838453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman Rest = SE.getAddExpr(NewAddOps); 839453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman ExposePointerBase(Base, Rest, SE); 840453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 841453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman} 842453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 843a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman/// getAddRecExprPHILiterally - Helper for expandAddRecExprLiterally. Expand 844a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman/// the base addrec, which is the addrec without any non-loop-dominating 845a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman/// values, and return the PHI. 846a10756ee657a4d43a48cca5c166919093930ed6bDan GohmanPHINode * 847a10756ee657a4d43a48cca5c166919093930ed6bDan GohmanSCEVExpander::getAddRecExprPHILiterally(const SCEVAddRecExpr *Normalized, 848a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const Loop *L, 849db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *ExpandTy, 850db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *IntTy) { 85193a896e2e36480d55de3bab53e68581e08526344Benjamin Kramer assert((!IVIncInsertLoop||IVIncInsertPos) && "Uninitialized insert position"); 852d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick 853a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Reuse a previously-inserted PHI, if present. 854a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman for (BasicBlock::iterator I = L->getHeader()->begin(); 855a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PHINode *PN = dyn_cast<PHINode>(I); ++I) 856572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman if (SE.isSCEVable(PN->getType()) && 857572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman (SE.getEffectiveSCEVType(PN->getType()) == 858572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman SE.getEffectiveSCEVType(Normalized->getType())) && 859572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman SE.getSCEV(PN) == Normalized) 860572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman if (BasicBlock *LatchBlock = L->getLoopLatch()) { 861572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman Instruction *IncV = 86222e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman cast<Instruction>(PN->getIncomingValueForBlock(LatchBlock)); 86322e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman 86422e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // Determine if this is a well-behaved chain of instructions leading 86522e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // back to the PHI. It probably will be, if we're scanning an inner 86622e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // loop already visited by LSR for example, but it wouldn't have 86722e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // to be. 86822e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman do { 8690cbe91ba3bd84a5ef68a1d0de5df6e955690b0a4Dan Gohman if (IncV->getNumOperands() == 0 || isa<PHINode>(IncV) || 870a7a841adb89efa6ad3b35e9d4bcccccfb8ca146aDan Gohman (isa<CastInst>(IncV) && !isa<BitCastInst>(IncV))) { 87122e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV = 0; 87222e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman break; 87322e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman } 8749feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman // If any of the operands don't dominate the insert position, bail. 8759feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman // Addrec operands are always loop-invariant, so this can only happen 8769feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman // if there are instructions which haven't been hoisted. 877d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick if (L == IVIncInsertLoop) { 878d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick for (User::op_iterator OI = IncV->op_begin()+1, 879d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick OE = IncV->op_end(); OI != OE; ++OI) 880d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick if (Instruction *OInst = dyn_cast<Instruction>(OI)) 881d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick if (!SE.DT->dominates(OInst, IVIncInsertPos)) { 882d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick IncV = 0; 883d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick break; 884d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick } 885d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick } 8869feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman if (!IncV) 8879feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman break; 8889feae9f0de032c66d01d16399a4c5296e38870e3Dan Gohman // Advance to the next instruction. 88922e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV = dyn_cast<Instruction>(IncV->getOperand(0)); 89022e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman if (!IncV) 89122e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman break; 89222e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman if (IncV->mayHaveSideEffects()) { 89322e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV = 0; 89422e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman break; 89522e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman } 89622e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman } while (IncV != PN); 89722e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman 89822e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman if (IncV) { 89922e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // Ok, the add recurrence looks usable. 90022e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // Remember this PHI, even in post-inc mode. 90122e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman InsertedValues.insert(PN); 90222e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // Remember the increment. 90322e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV = cast<Instruction>(PN->getIncomingValueForBlock(LatchBlock)); 90422e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman rememberInstruction(IncV); 90522e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman if (L == IVIncInsertLoop) 90622e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman do { 90722e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman if (SE.DT->dominates(IncV, IVIncInsertPos)) 90822e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman break; 90922e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // Make sure the increment is where we want it. But don't move it 91022e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman // down past a potential existing post-inc user. 91122e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV->moveBefore(IVIncInsertPos); 91222e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IVIncInsertPos = IncV; 91322e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman IncV = cast<Instruction>(IncV->getOperand(0)); 91422e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman } while (IncV != PN); 91522e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman return PN; 91622e621908fdb121474f4806f15ec5c0ce2efeb0aDan Gohman } 917572645cf84060c0fc25cb91d38cb9079918b3a88Dan Gohman } 918a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 919a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Save the original insertion point so we can restore it when we're done. 920a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 921a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 922a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 923a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Expand code for the start value. 924a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *StartV = expandCodeFor(Normalized->getStart(), ExpandTy, 925a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman L->getHeader()->begin()); 926a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 927d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick // StartV must be hoisted into L's preheader to dominate the new phi. 92893a896e2e36480d55de3bab53e68581e08526344Benjamin Kramer assert(!isa<Instruction>(StartV) || 92993a896e2e36480d55de3bab53e68581e08526344Benjamin Kramer SE.DT->properlyDominates(cast<Instruction>(StartV)->getParent(), 93093a896e2e36480d55de3bab53e68581e08526344Benjamin Kramer L->getHeader())); 931d152d03a476b8d0d4b26577db26e2ba76034b0f3Andrew Trick 932a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Expand code for the step value. Insert instructions right before the 933a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // terminator corresponding to the back-edge. Do this before creating the PHI 934a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // so that PHI reuse code doesn't see an incomplete PHI. If the stride is 935a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // negative, insert a sub instead of an add for the increment (unless it's a 936a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // constant, because subtracts of constants are canonicalized to adds). 937a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *Step = Normalized->getStepRecurrence(SE); 9381df9859c40492511b8aa4321eb76496005d3b75bDuncan Sands bool isPointer = ExpandTy->isPointerTy(); 939a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman bool isNegative = !isPointer && isNonConstantNegative(Step); 940a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (isNegative) 941a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Step = SE.getNegativeSCEV(Step); 942a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *StepV = expandCodeFor(Step, IntTy, L->getHeader()->begin()); 943a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 944a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Create the PHI. 945d8b4fb4aab4d6fedb2b14bed1b846451b17bde7cJay Foad BasicBlock *Header = L->getHeader(); 946d8b4fb4aab4d6fedb2b14bed1b846451b17bde7cJay Foad Builder.SetInsertPoint(Header, Header->begin()); 947d8b4fb4aab4d6fedb2b14bed1b846451b17bde7cJay Foad pred_iterator HPB = pred_begin(Header), HPE = pred_end(Header); 9485e7645be4c9dd2193add44d30b5fef8036d7a3ceAndrew Trick PHINode *PN = Builder.CreatePHI(ExpandTy, std::distance(HPB, HPE), 949dc8e546048db2f7ff5656742b2b26975098a11a0Andrew Trick Twine(IVName) + ".iv"); 950a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(PN); 951a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 952a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Create the step instructions and populate the PHI. 953d8b4fb4aab4d6fedb2b14bed1b846451b17bde7cJay Foad for (pred_iterator HPI = HPB; HPI != HPE; ++HPI) { 954a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman BasicBlock *Pred = *HPI; 955a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 956a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Add a start value. 957a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!L->contains(Pred)) { 958a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PN->addIncoming(StartV, Pred); 959a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman continue; 960a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 961a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 962a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Create a step value and add it to the PHI. If IVIncInsertLoop is 963a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // non-null and equal to the addrec's loop, insert the instructions 964a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // at IVIncInsertPos. 965a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Instruction *InsertPos = L == IVIncInsertLoop ? 966a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman IVIncInsertPos : Pred->getTerminator(); 967c5ecbdc1896f1cc089372feef3191ace2f840898Devang Patel Builder.SetInsertPoint(InsertPos); 968a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *IncV; 969a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // If the PHI is a pointer, use a GEP, otherwise use an add or sub. 970a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (isPointer) { 971db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner PointerType *GEPPtrTy = cast<PointerType>(ExpandTy); 972a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // If the step isn't constant, don't use an implicitly scaled GEP, because 973a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // that would require a multiply inside the loop. 974a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!isa<ConstantInt>(StepV)) 975a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman GEPPtrTy = PointerType::get(Type::getInt1Ty(SE.getContext()), 976a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman GEPPtrTy->getAddressSpace()); 977a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *const StepArray[1] = { SE.getSCEV(StepV) }; 978a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman IncV = expandAddToGEP(StepArray, StepArray+1, GEPPtrTy, IntTy, PN); 979a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (IncV->getType() != PN->getType()) { 980a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman IncV = Builder.CreateBitCast(IncV, PN->getType(), "tmp"); 981a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(IncV); 982a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 983a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } else { 984a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman IncV = isNegative ? 985dc8e546048db2f7ff5656742b2b26975098a11a0Andrew Trick Builder.CreateSub(PN, StepV, Twine(IVName) + ".iv.next") : 986dc8e546048db2f7ff5656742b2b26975098a11a0Andrew Trick Builder.CreateAdd(PN, StepV, Twine(IVName) + ".iv.next"); 987a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(IncV); 988a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 989a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PN->addIncoming(IncV, Pred); 990a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 991a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 992a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Restore the original insert point. 993a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (SaveInsertBB) 994455985501381777db03534c925a35e261e356395Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 995a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 996a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Remember this PHI, even in post-inc mode. 997a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman InsertedValues.insert(PN); 998a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 999a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman return PN; 1000a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman} 1001a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1002a10756ee657a4d43a48cca5c166919093930ed6bDan GohmanValue *SCEVExpander::expandAddRecExprLiterally(const SCEVAddRecExpr *S) { 1003db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *STy = S->getType(); 1004db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *IntTy = SE.getEffectiveSCEVType(STy); 1005a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const Loop *L = S->getLoop(); 1006a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1007a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Determine a normalized form of this expression, which is the expression 1008a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // before any post-inc adjustment is made. 1009a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEVAddRecExpr *Normalized = S; 1010448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman if (PostIncLoops.count(L)) { 1011448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman PostIncLoopSet Loops; 1012448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman Loops.insert(L); 1013448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman Normalized = 1014448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman cast<SCEVAddRecExpr>(TransformForPostIncUse(Normalize, S, 0, 0, 1015448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman Loops, SE, *SE.DT)); 1016a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1017a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1018a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Strip off any non-loop-dominating component from the addrec start. 1019a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *Start = Normalized->getStart(); 1020a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *PostLoopOffset = 0; 1021dc0e8fb9f9512622f55f73e1a434caa5c0915694Dan Gohman if (!SE.properlyDominates(Start, L->getHeader())) { 1022a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PostLoopOffset = Start; 1023deff621abdd48bd70434bd4d7ef30f08ddba1cd8Dan Gohman Start = SE.getConstant(Normalized->getType(), 0); 10243228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick Normalized = cast<SCEVAddRecExpr>( 10253228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick SE.getAddRecExpr(Start, Normalized->getStepRecurrence(SE), 10263228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick Normalized->getLoop(), 10273228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick // FIXME: Normalized->getNoWrapFlags(FlagNW) 10283228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick SCEV::FlagAnyWrap)); 1029a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1030a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1031a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Strip off any non-loop-dominating component from the addrec step. 1032a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *Step = Normalized->getStepRecurrence(SE); 1033a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *PostLoopScale = 0; 1034dc0e8fb9f9512622f55f73e1a434caa5c0915694Dan Gohman if (!SE.dominates(Step, L->getHeader())) { 1035a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PostLoopScale = Step; 1036deff621abdd48bd70434bd4d7ef30f08ddba1cd8Dan Gohman Step = SE.getConstant(Normalized->getType(), 1); 1037a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Normalized = 1038a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman cast<SCEVAddRecExpr>(SE.getAddRecExpr(Start, Step, 10393228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick Normalized->getLoop(), 10403228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick // FIXME: Normalized 10413228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick // ->getNoWrapFlags(FlagNW) 10423228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick SCEV::FlagAnyWrap)); 1043a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1044a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1045a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Expand the core addrec. If we need post-loop scaling, force it to 1046a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // expand to an integer type to avoid the need for additional casting. 1047db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *ExpandTy = PostLoopScale ? IntTy : STy; 1048a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman PHINode *PN = getAddRecExprPHILiterally(Normalized, L, ExpandTy, IntTy); 1049a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 10503f46a3abeedba8d517b4182de34c821d752db058Dan Gohman // Accommodate post-inc mode, if necessary. 1051a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Value *Result; 1052448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman if (!PostIncLoops.count(L)) 1053a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Result = PN; 1054a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman else { 1055a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // In PostInc mode, use the post-incremented value. 1056a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman BasicBlock *LatchBlock = L->getLoopLatch(); 1057a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman assert(LatchBlock && "PostInc mode requires a unique loop latch!"); 1058a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Result = PN->getIncomingValueForBlock(LatchBlock); 1059a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1060a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1061a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Re-apply any non-loop-dominating scale. 1062a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (PostLoopScale) { 10630a799ab15801d4ebf68eeb151d6375a799c87d9aDan Gohman Result = InsertNoopCastOfTo(Result, IntTy); 1064a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Result = Builder.CreateMul(Result, 1065a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman expandCodeFor(PostLoopScale, IntTy)); 1066a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(Result); 1067a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1068a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1069a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman // Re-apply any non-loop-dominating offset. 1070a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (PostLoopOffset) { 1071db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (PointerType *PTy = dyn_cast<PointerType>(ExpandTy)) { 1072a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman const SCEV *const OffsetArray[1] = { PostLoopOffset }; 1073a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Result = expandAddToGEP(OffsetArray, OffsetArray+1, PTy, IntTy, Result); 1074a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } else { 10750a799ab15801d4ebf68eeb151d6375a799c87d9aDan Gohman Result = InsertNoopCastOfTo(Result, IntTy); 1076a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman Result = Builder.CreateAdd(Result, 1077a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman expandCodeFor(PostLoopOffset, IntTy)); 1078a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(Result); 1079a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1080a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman } 1081a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1082a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman return Result; 1083a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman} 1084a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1085890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitAddRecExpr(const SCEVAddRecExpr *S) { 1086a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman if (!CanonicalMode) return expandAddRecExprLiterally(S); 1087a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman 1088db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty = SE.getEffectiveSCEVType(S->getType()); 108936f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman const Loop *L = S->getLoop(); 109036f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 10914d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // First check for an existing canonical IV in a suitable type. 10924d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman PHINode *CanonicalIV = 0; 10934d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (PHINode *PN = L->getCanonicalInductionVariable()) 1094133e295b363c89b6a3da7aba3ac5ae6332429e46Dan Gohman if (SE.getTypeSizeInBits(PN->getType()) >= SE.getTypeSizeInBits(Ty)) 10954d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman CanonicalIV = PN; 10964d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman 10974d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // Rewrite an AddRec in terms of the canonical induction variable, if 10984d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // its type is more narrow. 10994d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (CanonicalIV && 11004d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman SE.getTypeSizeInBits(CanonicalIV->getType()) > 11014d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman SE.getTypeSizeInBits(Ty)) { 1102f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman SmallVector<const SCEV *, 4> NewOps(S->getNumOperands()); 1103f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman for (unsigned i = 0, e = S->getNumOperands(); i != e; ++i) 1104f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman NewOps[i] = SE.getAnyExtendExpr(S->op_begin()[i], CanonicalIV->getType()); 11053228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick Value *V = expand(SE.getAddRecExpr(NewOps, S->getLoop(), 11063228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick // FIXME: S->getNoWrapFlags(FlagNW) 11073228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick SCEV::FlagAnyWrap)); 1108267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 1109267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 11104d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman BasicBlock::iterator NewInsertPt = 11117896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner llvm::next(BasicBlock::iterator(cast<Instruction>(V))); 111208f55d02da2cd24f3b4297259ef6429b8bf1ef97Jim Grosbach while (isa<PHINode>(NewInsertPt) || isa<DbgInfoIntrinsic>(NewInsertPt)) 111308f55d02da2cd24f3b4297259ef6429b8bf1ef97Jim Grosbach ++NewInsertPt; 11144d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman V = expandCodeFor(SE.getTruncateExpr(SE.getUnknown(V), Ty), 0, 11154d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman NewInsertPt); 1116455985501381777db03534c925a35e261e356395Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 11174d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman return V; 11184d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman } 11194d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman 112036f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // {X,+,F} --> X + {0,+,F} 1121cfeb6a450632f2a6cd05302633c8c2b8c90cfdfdDan Gohman if (!S->getStart()->isZero()) { 1122f9e64729afec646fe93b51417e66e552e8e630a4Dan Gohman SmallVector<const SCEV *, 4> NewOps(S->op_begin(), S->op_end()); 1123deff621abdd48bd70434bd4d7ef30f08ddba1cd8Dan Gohman NewOps[0] = SE.getConstant(Ty, 0); 11243228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick // FIXME: can use S->getNoWrapFlags() 11253228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick const SCEV *Rest = SE.getAddRecExpr(NewOps, L, SCEV::FlagAnyWrap); 1126453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 1127453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // Turn things like ptrtoint+arithmetic+inttoptr into GEP. See the 1128453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman // comments on expandAddToGEP for details. 1129c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *Base = S->getStart(); 1130c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman const SCEV *RestArray[1] = { Rest }; 1131c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Dig into the expression to find the pointer base for a GEP. 1132c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman ExposePointerBase(Base, RestArray[0], SE); 1133c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // If we found a pointer, expand the AddRec with a GEP. 1134db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (PointerType *PTy = dyn_cast<PointerType>(Base->getType())) { 1135c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // Make sure the Base isn't something exotic, such as a multiplied 1136c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // or divided pointer value. In those cases, the result type isn't 1137c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman // actually a pointer type. 1138c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman if (!isa<SCEVMulExpr>(Base) && !isa<SCEVUDivExpr>(Base)) { 1139c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman Value *StartV = expand(Base); 1140c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman assert(StartV->getType() == PTy && "Pointer type mismatch for GEP!"); 1141c40f17b08774c2dcc5787fd83241e3c64ba82974Dan Gohman return expandAddToGEP(RestArray, RestArray+1, PTy, Ty, StartV); 1142453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 1143453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman } 1144453aa4fbf1083cc7f646a0ac21e2bcc384a91ae9Dan Gohman 114540a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // Just do a normal add. Pre-expand the operands to suppress folding. 114640a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return expand(SE.getAddExpr(SE.getUnknown(expand(S->getStart())), 114740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman SE.getUnknown(expand(Rest)))); 114836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman } 114936f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 11506ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman // If we don't yet have a canonical IV, create one. 11516ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman if (!CanonicalIV) { 115236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // Create and insert the PHI node for the induction variable in the 115336f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // specified loop. 115436f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman BasicBlock *Header = L->getHeader(); 1155d8b4fb4aab4d6fedb2b14bed1b846451b17bde7cJay Foad pred_iterator HPB = pred_begin(Header), HPE = pred_end(Header); 11563ecfc861b4365f341c5c969b40e1afccde676e6fJay Foad CanonicalIV = PHINode::Create(Ty, std::distance(HPB, HPE), "indvar", 11573ecfc861b4365f341c5c969b40e1afccde676e6fJay Foad Header->begin()); 11586ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman rememberInstruction(CanonicalIV); 115936f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 1160eed707b1e6097aac2bb6b3d47271f6300ace7f2eOwen Anderson Constant *One = ConstantInt::get(Ty, 1); 1161d8b4fb4aab4d6fedb2b14bed1b846451b17bde7cJay Foad for (pred_iterator HPI = HPB; HPI != HPE; ++HPI) { 11627656018c2268285907cfdc106071462a01a73878Gabor Greif BasicBlock *HP = *HPI; 11637656018c2268285907cfdc106071462a01a73878Gabor Greif if (L->contains(HP)) { 11643abf905b50f33340ae81913da81b0eda96fa4616Dan Gohman // Insert a unit add instruction right before the terminator 11653abf905b50f33340ae81913da81b0eda96fa4616Dan Gohman // corresponding to the back-edge. 11666ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman Instruction *Add = BinaryOperator::CreateAdd(CanonicalIV, One, 11676ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman "indvar.next", 11686ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman HP->getTerminator()); 1169df3ad6697bb849e514c0881ca8700ea36678cbdaDevang Patel Add->setDebugLoc(HP->getTerminator()->getDebugLoc()); 1170a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(Add); 11716ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman CanonicalIV->addIncoming(Add, HP); 117283d577490b1473213b6973236110c28e59127956Dan Gohman } else { 11736ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman CanonicalIV->addIncoming(Constant::getNullValue(Ty), HP); 117483d577490b1473213b6973236110c28e59127956Dan Gohman } 11757656018c2268285907cfdc106071462a01a73878Gabor Greif } 117636f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman } 117736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 11786ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman // {0,+,1} --> Insert a canonical induction variable into the loop! 11796ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman if (S->isAffine() && S->getOperand(1)->isOne()) { 11806ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman assert(Ty == SE.getEffectiveSCEVType(CanonicalIV->getType()) && 11816ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman "IVs with types different from the canonical IV should " 11826ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman "already have been handled!"); 11836ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman return CanonicalIV; 11846ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman } 11856ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman 11864d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // {0,+,F} --> {0,+,1} * F 118736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 1188df14a04b5ccbbe6a46c2ccb93e27b12a36ff163eChris Lattner // If this is a simple linear addrec, emit it now as a special case. 118940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (S->isAffine()) // {0,+,F} --> i*F 119040a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return 119140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman expand(SE.getTruncateOrNoop( 11926ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman SE.getMulExpr(SE.getUnknown(CanonicalIV), 119340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman SE.getNoopOrAnyExtend(S->getOperand(1), 11946ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman CanonicalIV->getType())), 119540a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman Ty)); 119636f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 119736f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // If this is a chain of recurrences, turn it into a closed form, using the 119836f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // folders, then expandCodeFor the closed form. This allows the folders to 119936f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // simplify the expression without having to build a bunch of special code 120036f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman // into this folder. 12016ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman const SCEV *IH = SE.getUnknown(CanonicalIV); // Get I as a "symbolic" SCEV. 120236f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 12034d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // Promote S up to the canonical IV type, if the cast is foldable. 12040bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *NewS = S; 12056ebfd72f37325a1ebceb53e5ecad524d359d8d0bDan Gohman const SCEV *Ext = SE.getNoopOrAnyExtend(S, CanonicalIV->getType()); 12064d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman if (isa<SCEVAddRecExpr>(Ext)) 12074d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman NewS = Ext; 12084d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman 12090bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *V = cast<SCEVAddRecExpr>(NewS)->evaluateAtIteration(IH, SE); 1210e81561909d128c6e2d8033cb5465a49b2596b26aBill Wendling //cerr << "Evaluated: " << *this << "\n to: " << *V << "\n"; 121136f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman 12124d8414f42033a5e744e8e60d2ca188b424c76168Dan Gohman // Truncate the result down to the original type, if needed. 12130bba49cebc50c7bd4662a4807bcb3ee7f42cb470Dan Gohman const SCEV *T = SE.getTruncateOrNoop(V, Ty); 1214469f3cdc13851914f3a766cbd8f701cf8431cacaDan Gohman return expand(T); 121536f891bdf6cf38fcc655a0930ca18664e18518d4Nate Begeman} 121696fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov 1217890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitTruncateExpr(const SCEVTruncateExpr *S) { 1218db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty = SE.getEffectiveSCEVType(S->getType()); 121992fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *V = expandCodeFor(S->getOperand(), 122092fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman SE.getEffectiveSCEVType(S->getOperand()->getType())); 1221267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *I = Builder.CreateTrunc(V, Ty, "tmp"); 1222a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(I); 1223cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return I; 122411f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 122511f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 1226890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitZeroExtendExpr(const SCEVZeroExtendExpr *S) { 1227db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty = SE.getEffectiveSCEVType(S->getType()); 122892fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *V = expandCodeFor(S->getOperand(), 122992fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman SE.getEffectiveSCEVType(S->getOperand()->getType())); 1230267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *I = Builder.CreateZExt(V, Ty, "tmp"); 1231a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(I); 1232cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return I; 123311f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 123411f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 1235890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitSignExtendExpr(const SCEVSignExtendExpr *S) { 1236db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty = SE.getEffectiveSCEVType(S->getType()); 123792fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *V = expandCodeFor(S->getOperand(), 123892fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman SE.getEffectiveSCEVType(S->getOperand()->getType())); 1239267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *I = Builder.CreateSExt(V, Ty, "tmp"); 1240a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(I); 1241cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman return I; 124211f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 124311f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 1244890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitSMaxExpr(const SCEVSMaxExpr *S) { 12450196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Value *LHS = expand(S->getOperand(S->getNumOperands()-1)); 1246db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty = LHS->getType(); 12470196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman for (int i = S->getNumOperands()-2; i >= 0; --i) { 12480196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, do the 12490196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // rest of the comparisons as integer. 12500196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (S->getOperand(i)->getType() != Ty) { 12510196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Ty = SE.getEffectiveSCEVType(Ty); 12520196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, Ty); 12530196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman } 125492fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *RHS = expandCodeFor(S->getOperand(i), Ty); 1255267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *ICmp = Builder.CreateICmpSGT(LHS, RHS, "tmp"); 1256a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(ICmp); 1257267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *Sel = Builder.CreateSelect(ICmp, LHS, RHS, "smax"); 1258a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(Sel); 1259cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman LHS = Sel; 1260c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky } 12610196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, cast the 12620196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // final result back to the pointer type. 12630196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (LHS->getType() != S->getType()) 12640196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, S->getType()); 1265c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky return LHS; 1266c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky} 1267c54c561c9f7270c055dd7ba75a3a003b771a42d9Nick Lewycky 1268890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::visitUMaxExpr(const SCEVUMaxExpr *S) { 12690196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Value *LHS = expand(S->getOperand(S->getNumOperands()-1)); 1270db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty = LHS->getType(); 12710196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman for (int i = S->getNumOperands()-2; i >= 0; --i) { 12720196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, do the 12730196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // rest of the comparisons as integer. 12740196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (S->getOperand(i)->getType() != Ty) { 12750196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman Ty = SE.getEffectiveSCEVType(Ty); 12760196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, Ty); 12770196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman } 127892fcdcac543653a62949fe9e5a7bd008500c1380Dan Gohman Value *RHS = expandCodeFor(S->getOperand(i), Ty); 1279267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *ICmp = Builder.CreateICmpUGT(LHS, RHS, "tmp"); 1280a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(ICmp); 1281267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Value *Sel = Builder.CreateSelect(ICmp, LHS, RHS, "umax"); 1282a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman rememberInstruction(Sel); 1283cf5ab820227dedd77fb91d0904b6dc3694a7c196Dan Gohman LHS = Sel; 12843e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky } 12850196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // In the case of mixed integer and pointer types, cast the 12860196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman // final result back to the pointer type. 12870196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman if (LHS->getType() != S->getType()) 12880196dc5733bf3c6a71f7de1f631f2c43e5809fd9Dan Gohman LHS = InsertNoopCastOfTo(LHS, S->getType()); 12893e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky return LHS; 12903e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky} 12913e6307698084e7adfc10b739442ae29742beefd0Nick Lewycky 1292db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris LattnerValue *SCEVExpander::expandCodeFor(const SCEV *SH, Type *Ty, 12936c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman Instruction *I) { 12946c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman BasicBlock::iterator IP = I; 12956c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman while (isInsertedInstruction(IP) || isa<DbgInfoIntrinsic>(IP)) 12966c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman ++IP; 12976c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman Builder.SetInsertPoint(IP->getParent(), IP); 12986c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman return expandCodeFor(SH, Ty); 12996c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman} 13006c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman 1301db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris LattnerValue *SCEVExpander::expandCodeFor(const SCEV *SH, Type *Ty) { 130211f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman // Expand the code for this SCEV. 13032d1be87ee40a4a0241d94448173879d9df2bc5b3Dan Gohman Value *V = expand(SH); 13045be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman if (Ty) { 13055be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman assert(SE.getTypeSizeInBits(Ty) == SE.getTypeSizeInBits(SH->getType()) && 13065be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman "non-trivial casts should be done with the SCEVs directly!"); 13075be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman V = InsertNoopCastOfTo(V, Ty); 13085be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman } 13095be18e84766fb495b0bde3c8244c1df459a18683Dan Gohman return V; 131011f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman} 131111f6d3b478c4fa09d126833c57fbac1d795ead31Dan Gohman 1312890f92b744fb074465bc2b7006ee753a181f62a4Dan GohmanValue *SCEVExpander::expand(const SCEV *S) { 131340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // Compute an insertion point for this SCEV object. Hoist the instructions 131440a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // as far out in the loop nest as possible. 1315267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Instruction *InsertPt = Builder.GetInsertPoint(); 1316267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman for (Loop *L = SE.LI->getLoopFor(Builder.GetInsertBlock()); ; 131740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman L = L->getParentLoop()) 131817ead4ff4baceb2c5503f233d0288d363ae44165Dan Gohman if (SE.isLoopInvariant(S, L)) { 131940a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman if (!L) break; 1320e059ee832ca36d65a5fb87b0ac5bcdb0490b15cbDan Gohman if (BasicBlock *Preheader = L->getLoopPreheader()) 132140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman InsertPt = Preheader->getTerminator(); 132240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman } else { 132340a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // If the SCEV is computable at this level, insert it into the header 132440a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // after the PHIs (and after any other instructions that we've inserted 132540a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman // there) so that it is guaranteed to dominate any user inside the loop. 132617ead4ff4baceb2c5503f233d0288d363ae44165Dan Gohman if (L && SE.hasComputableLoopEvolution(S, L) && !PostIncLoops.count(L)) 132740a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman InsertPt = L->getHeader()->getFirstNonPHI(); 13286c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman while (isInsertedInstruction(InsertPt) || isa<DbgInfoIntrinsic>(InsertPt)) 13297896c9f436a4eda5ec15e882a7505ba482a2fcd0Chris Lattner InsertPt = llvm::next(BasicBlock::iterator(InsertPt)); 133040a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman break; 133140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman } 133240a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman 1333667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman // Check to see if we already expanded this here. 1334667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman std::map<std::pair<const SCEV *, Instruction *>, 1335667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman AssertingVH<Value> >::iterator I = 1336667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman InsertedExpressions.find(std::make_pair(S, InsertPt)); 1337267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (I != InsertedExpressions.end()) 1338667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman return I->second; 1339267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman 1340267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 1341267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 1342267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman Builder.SetInsertPoint(InsertPt->getParent(), InsertPt); 1343667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman 1344667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman // Expand the expression into instructions. 134596fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov Value *V = visit(S); 134640a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman 1347667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman // Remember the expanded value for this SCEV at this location. 1348448db1cdef5872713ef77beffacf502ae3450cd7Dan Gohman if (PostIncLoops.empty()) 1349a10756ee657a4d43a48cca5c166919093930ed6bDan Gohman InsertedExpressions[std::make_pair(S, InsertPt)] = V; 1350667d787c0a21cf3f5dfcde03ca471162ba35b614Dan Gohman 1351455985501381777db03534c925a35e261e356395Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 135296fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov return V; 135396fea337d27357e9b62abbf3d2d5ce29f1c8e870Anton Korobeynikov} 13541d09de3eca23267855e28297fcb40de3632ea47bDan Gohman 13551d826a76f591afea445489b9a5485c345e66bf87Dan Gohmanvoid SCEVExpander::rememberInstruction(Value *I) { 135625fcaff409f5c4c6da08f148ffb9404a71e8e4a7Dan Gohman if (!PostIncLoops.empty()) 135725fcaff409f5c4c6da08f148ffb9404a71e8e4a7Dan Gohman InsertedPostIncValues.insert(I); 135825fcaff409f5c4c6da08f148ffb9404a71e8e4a7Dan Gohman else 13591d826a76f591afea445489b9a5485c345e66bf87Dan Gohman InsertedValues.insert(I); 13601d826a76f591afea445489b9a5485c345e66bf87Dan Gohman 13611d826a76f591afea445489b9a5485c345e66bf87Dan Gohman // If we just claimed an existing instruction and that instruction had 13623228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick // been the insert point, adjust the insert point forward so that 13631d826a76f591afea445489b9a5485c345e66bf87Dan Gohman // subsequently inserted code will be dominated. 13641d826a76f591afea445489b9a5485c345e66bf87Dan Gohman if (Builder.GetInsertPoint() == I) { 13651d826a76f591afea445489b9a5485c345e66bf87Dan Gohman BasicBlock::iterator It = cast<Instruction>(I); 13666c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman do { ++It; } while (isInsertedInstruction(It) || 13676c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman isa<DbgInfoIntrinsic>(It)); 13681d826a76f591afea445489b9a5485c345e66bf87Dan Gohman Builder.SetInsertPoint(Builder.GetInsertBlock(), It); 13691d826a76f591afea445489b9a5485c345e66bf87Dan Gohman } 13701d826a76f591afea445489b9a5485c345e66bf87Dan Gohman} 13711d826a76f591afea445489b9a5485c345e66bf87Dan Gohman 1372455985501381777db03534c925a35e261e356395Dan Gohmanvoid SCEVExpander::restoreInsertPoint(BasicBlock *BB, BasicBlock::iterator I) { 13733f46a3abeedba8d517b4182de34c821d752db058Dan Gohman // If we acquired more instructions since the old insert point was saved, 1374455985501381777db03534c925a35e261e356395Dan Gohman // advance past them. 13756c7ed6b54949949806797bafdf545fbfecb2cef5Dan Gohman while (isInsertedInstruction(I) || isa<DbgInfoIntrinsic>(I)) ++I; 1376455985501381777db03534c925a35e261e356395Dan Gohman 1377455985501381777db03534c925a35e261e356395Dan Gohman Builder.SetInsertPoint(BB, I); 1378455985501381777db03534c925a35e261e356395Dan Gohman} 1379455985501381777db03534c925a35e261e356395Dan Gohman 13801d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// getOrInsertCanonicalInductionVariable - This method returns the 13811d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// canonical induction variable of the specified type for the specified 13821d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// loop (inserting one if there is none). A canonical induction variable 13831d09de3eca23267855e28297fcb40de3632ea47bDan Gohman/// starts at zero and steps by one on each iteration. 13847c58dbd88c36c5d6c411ea6c046ddcff4c5841e9Dan GohmanPHINode * 13851d09de3eca23267855e28297fcb40de3632ea47bDan GohmanSCEVExpander::getOrInsertCanonicalInductionVariable(const Loop *L, 1386db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *Ty) { 1387b0bc6c361da9009e8414efde317d9bbff755f6c0Duncan Sands assert(Ty->isIntegerTy() && "Can only insert integer induction variables!"); 1388133e295b363c89b6a3da7aba3ac5ae6332429e46Dan Gohman 1389133e295b363c89b6a3da7aba3ac5ae6332429e46Dan Gohman // Build a SCEV for {0,+,1}<L>. 13903228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick // Conservatively use FlagAnyWrap for now. 1391deff621abdd48bd70434bd4d7ef30f08ddba1cd8Dan Gohman const SCEV *H = SE.getAddRecExpr(SE.getConstant(Ty, 0), 13923228cc259b5ca00e46af36da369a451f5736cbf4Andrew Trick SE.getConstant(Ty, 1), L, SCEV::FlagAnyWrap); 1393133e295b363c89b6a3da7aba3ac5ae6332429e46Dan Gohman 1394133e295b363c89b6a3da7aba3ac5ae6332429e46Dan Gohman // Emit code for it. 1395267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock *SaveInsertBB = Builder.GetInsertBlock(); 1396267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman BasicBlock::iterator SaveInsertPt = Builder.GetInsertPoint(); 13977c58dbd88c36c5d6c411ea6c046ddcff4c5841e9Dan Gohman PHINode *V = cast<PHINode>(expandCodeFor(H, 0, L->getHeader()->begin())); 1398267a385342f2e7388f178b327dd87c5f29afd51bDan Gohman if (SaveInsertBB) 1399455985501381777db03534c925a35e261e356395Dan Gohman restoreInsertPoint(SaveInsertBB, SaveInsertPt); 1400133e295b363c89b6a3da7aba3ac5ae6332429e46Dan Gohman 140140a5a1b39ee1cd40ff9d04740386b667fb27b340Dan Gohman return V; 14021d09de3eca23267855e28297fcb40de3632ea47bDan Gohman} 1403