PeepholeOptimizer.cpp revision 39cc5138707eee563db7a487cd720b232b4b58fd
16cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling//===-- PeepholeOptimizer.cpp - Peephole Optimizations --------------------===// 27da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng// 37da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng// The LLVM Compiler Infrastructure 47da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng// 57da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng// This file is distributed under the University of Illinois Open Source 67da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng// License. See LICENSE.TXT for details. 77da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng// 87da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng//===----------------------------------------------------------------------===// 9d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng// 106cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// Perform peephole optimizations on the machine code: 11d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng// 126cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// - Optimize Extensions 13d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng// 146cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// Optimization of sign / zero extension instructions. It may be extended to 156cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// handle other instructions with similar properties. 166cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// 176cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// On some targets, some instructions, e.g. X86 sign / zero extension, may 186cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// leave the source value in the lower part of the result. This optimization 196cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// will replace some uses of the pre-extension value with uses of the 206cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// sub-register of the results. 216cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// 226cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// - Optimize Comparisons 236cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// 246cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// Optimization of comparison instructions. For instance, in this code: 256cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// 266cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// sub r1, 1 276cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// cmp r1, 0 286cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// bz L1 296cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// 306cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// If the "sub" instruction all ready sets (or could be modified to set) the 316cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// same flag that the "cmp" instruction sets and that "bz" uses, then we can 326cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// eliminate the "cmp" instruction. 33d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng// 34d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng// - Optimize Bitcast pairs: 35d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng// 36d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng// v1 = bitcast v0 37d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng// v2 = bitcast v1 38d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng// = v2 39d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng// => 40d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng// v1 = bitcast v0 41d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng// = v0 421df91b0e54bc62f8fc7a06a4f75220e40aa2dfe0Andrew Trick// 43d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng//===----------------------------------------------------------------------===// 447da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng 456cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling#define DEBUG_TYPE "peephole-opt" 467da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng#include "llvm/CodeGen/Passes.h" 477da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng#include "llvm/CodeGen/MachineDominators.h" 487da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng#include "llvm/CodeGen/MachineInstrBuilder.h" 497da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng#include "llvm/CodeGen/MachineRegisterInfo.h" 507da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng#include "llvm/Target/TargetInstrInfo.h" 517da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng#include "llvm/Target/TargetRegisterInfo.h" 527da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng#include "llvm/Support/CommandLine.h" 53c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng#include "llvm/ADT/DenseMap.h" 547da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng#include "llvm/ADT/SmallPtrSet.h" 55c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng#include "llvm/ADT/SmallSet.h" 567da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng#include "llvm/ADT/Statistic.h" 577da9ecf9677b751d81515f95168ae3cb2df54160Evan Chengusing namespace llvm; 587da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng 596cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling// Optimize Extensions 606cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendlingstatic cl::opt<bool> 616cdb1abe4e4f6364649e7ef656589441754e82aeBill WendlingAggressive("aggressive-ext-opt", cl::Hidden, 626cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling cl::desc("Aggressive extension optimization")); 637da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng 6440a5eb18b031fa1a5e9697e21e251e613d441cc5Bill Wendlingstatic cl::opt<bool> 6540a5eb18b031fa1a5e9697e21e251e613d441cc5Bill WendlingDisablePeephole("disable-peephole", cl::Hidden, cl::init(false), 6640a5eb18b031fa1a5e9697e21e251e613d441cc5Bill Wendling cl::desc("Disable the peephole optimizer")); 6740a5eb18b031fa1a5e9697e21e251e613d441cc5Bill Wendling 6869c5eb59f592087af89b971bea072f070f2a5cfaBill WendlingSTATISTIC(NumReuse, "Number of extension results reused"); 69d158fba3e45547f013bbab4c0ac640f31b5e341fEvan ChengSTATISTIC(NumBitcasts, "Number of bitcasts eliminated"); 70d158fba3e45547f013bbab4c0ac640f31b5e341fEvan ChengSTATISTIC(NumCmps, "Number of compares eliminated"); 713b26eb62946a64409f81c8089a362eb582114342Lang HamesSTATISTIC(NumImmFold, "Number of move immediate folded"); 726cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling 737da9ecf9677b751d81515f95168ae3cb2df54160Evan Chengnamespace { 746cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling class PeepholeOptimizer : public MachineFunctionPass { 757da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng const TargetMachine *TM; 767da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng const TargetInstrInfo *TII; 776cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling MachineRegisterInfo *MRI; 786cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling MachineDominatorTree *DT; // Machine dominator tree 797da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng 807da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng public: 817da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng static char ID; // Pass identification 82081c34b725980f995be9080eaec24cd3dfaaf065Owen Anderson PeepholeOptimizer() : MachineFunctionPass(ID) { 83081c34b725980f995be9080eaec24cd3dfaaf065Owen Anderson initializePeepholeOptimizerPass(*PassRegistry::getPassRegistry()); 84081c34b725980f995be9080eaec24cd3dfaaf065Owen Anderson } 857da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng 867da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng virtual bool runOnMachineFunction(MachineFunction &MF); 877da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng 887da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng virtual void getAnalysisUsage(AnalysisUsage &AU) const { 897da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng AU.setPreservesCFG(); 907da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng MachineFunctionPass::getAnalysisUsage(AU); 91d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng if (Aggressive) { 92d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng AU.addRequired<MachineDominatorTree>(); 93d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng AU.addPreserved<MachineDominatorTree>(); 94d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng } 957da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng } 96d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng 97d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng private: 9839cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach bool optimizeBitcastInstr(MachineInstr *MI, MachineBasicBlock *MBB); 9939cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach bool optimizeCmpInstr(MachineInstr *MI, MachineBasicBlock *MBB); 10039cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach bool optimizeExtInstr(MachineInstr *MI, MachineBasicBlock *MBB, 1016cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling SmallPtrSet<MachineInstr*, 8> &LocalMIs); 102c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng bool isMoveImmediate(MachineInstr *MI, 103c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng SmallSet<unsigned, 4> &ImmDefRegs, 104c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng DenseMap<unsigned, MachineInstr*> &ImmDefMIs); 10539cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach bool foldImmediate(MachineInstr *MI, MachineBasicBlock *MBB, 106c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng SmallSet<unsigned, 4> &ImmDefRegs, 107c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng DenseMap<unsigned, MachineInstr*> &ImmDefMIs); 1087da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng }; 1097da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng} 1107da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng 1116cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendlingchar PeepholeOptimizer::ID = 0; 1121dd8c8560d45d36a8e507cd014352f1d313f9f9eAndrew Trickchar &llvm::PeepholeOptimizerID = PeepholeOptimizer::ID; 1132ab36d350293c77fc8941ce1023e4899df7e3a82Owen AndersonINITIALIZE_PASS_BEGIN(PeepholeOptimizer, "peephole-opts", 1142ab36d350293c77fc8941ce1023e4899df7e3a82Owen Anderson "Peephole Optimizations", false, false) 1152ab36d350293c77fc8941ce1023e4899df7e3a82Owen AndersonINITIALIZE_PASS_DEPENDENCY(MachineDominatorTree) 1162ab36d350293c77fc8941ce1023e4899df7e3a82Owen AndersonINITIALIZE_PASS_END(PeepholeOptimizer, "peephole-opts", 117ce665bd2e2b581ab0858d1afe359192bac96b868Owen Anderson "Peephole Optimizations", false, false) 1186cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling 11939cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach/// optimizeExtInstr - If instruction is a copy-like instruction, i.e. it reads 1206cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling/// a single register and writes a single register and it does not modify the 1216cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling/// source, and if the source value is preserved as a sub-register of the 1226cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling/// result, then replace all reachable uses of the source with the subreg of the 1236cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling/// result. 1241df91b0e54bc62f8fc7a06a4f75220e40aa2dfe0Andrew Trick/// 1256cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling/// Do not generate an EXTRACT that is used only in a debug use, as this changes 1266cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling/// the code. Since this code does not currently share EXTRACTs, just ignore all 1276cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling/// debug uses. 1286cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendlingbool PeepholeOptimizer:: 12939cc5138707eee563db7a487cd720b232b4b58fdJim GrosbachoptimizeExtInstr(MachineInstr *MI, MachineBasicBlock *MBB, 1306cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling SmallPtrSet<MachineInstr*, 8> &LocalMIs) { 131d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng unsigned SrcReg, DstReg, SubIdx; 13294e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (!TII->isCoalescableExtInstr(*MI, SrcReg, DstReg, SubIdx)) 13394e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling return false; 1341df91b0e54bc62f8fc7a06a4f75220e40aa2dfe0Andrew Trick 13594e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (TargetRegisterInfo::isPhysicalRegister(DstReg) || 13694e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling TargetRegisterInfo::isPhysicalRegister(SrcReg)) 13794e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling return false; 13894e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling 13994e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling MachineRegisterInfo::use_nodbg_iterator UI = MRI->use_nodbg_begin(SrcReg); 14094e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (++UI == MRI->use_nodbg_end()) 14194e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // No other uses. 14294e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling return false; 14394e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling 1446cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling // The source has other uses. See if we can replace the other uses with use of 1456cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling // the result of the extension. 14694e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling SmallPtrSet<MachineBasicBlock*, 4> ReachedBBs; 14794e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling UI = MRI->use_nodbg_begin(DstReg); 14894e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling for (MachineRegisterInfo::use_nodbg_iterator UE = MRI->use_nodbg_end(); 14994e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling UI != UE; ++UI) 15094e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling ReachedBBs.insert(UI->getParent()); 15194e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling 15294e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // Uses that are in the same BB of uses of the result of the instruction. 15394e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling SmallVector<MachineOperand*, 8> Uses; 1546cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling 15594e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // Uses that the result of the instruction can reach. 15694e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling SmallVector<MachineOperand*, 8> ExtendedUses; 15794e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling 1586cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling bool ExtendLife = true; 15994e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling UI = MRI->use_nodbg_begin(SrcReg); 16094e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling for (MachineRegisterInfo::use_nodbg_iterator UE = MRI->use_nodbg_end(); 16194e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling UI != UE; ++UI) { 16294e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling MachineOperand &UseMO = UI.getOperand(); 16394e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling MachineInstr *UseMI = &*UI; 16494e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (UseMI == MI) 16594e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling continue; 1666cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling 16794e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (UseMI->isPHI()) { 16894e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling ExtendLife = false; 16994e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling continue; 17094e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling } 171d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng 17294e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // It's an error to translate this: 17394e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // 17494e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // %reg1025 = <sext> %reg1024 17594e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // ... 17694e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // %reg1026 = SUBREG_TO_REG 0, %reg1024, 4 17794e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // 17894e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // into this: 17994e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // 18094e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // %reg1025 = <sext> %reg1024 18194e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // ... 18294e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // %reg1027 = COPY %reg1025:4 18394e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // %reg1026 = SUBREG_TO_REG 0, %reg1027, 4 18494e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // 18594e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // The problem here is that SUBREG_TO_REG is there to assert that an 18694e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // implicit zext occurs. It doesn't insert a zext instruction. If we allow 18794e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // the COPY here, it will give us the value after the <sext>, not the 18894e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // original value of %reg1024 before <sext>. 18994e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (UseMI->getOpcode() == TargetOpcode::SUBREG_TO_REG) 19094e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling continue; 19194e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling 19294e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling MachineBasicBlock *UseMBB = UseMI->getParent(); 19394e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (UseMBB == MBB) { 19494e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // Local uses that come after the extension. 19594e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (!LocalMIs.count(UseMI)) 19694e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling Uses.push_back(&UseMO); 1976cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling } else if (ReachedBBs.count(UseMBB)) { 1986cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling // Non-local uses where the result of the extension is used. Always 1996cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling // replace these unless it's a PHI. 20094e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling Uses.push_back(&UseMO); 2016cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling } else if (Aggressive && DT->dominates(MBB, UseMBB)) { 2026cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling // We may want to extend the live range of the extension result in order 2036cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling // to replace these uses. 20494e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling ExtendedUses.push_back(&UseMO); 2056cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling } else { 20694e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // Both will be live out of the def MBB anyway. Don't extend live range of 20794e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // the extension result. 20894e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling ExtendLife = false; 20994e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling break; 21094e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling } 21194e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling } 212d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng 21394e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (ExtendLife && !ExtendedUses.empty()) 2146cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling // Extend the liveness of the extension result. 21594e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling std::copy(ExtendedUses.begin(), ExtendedUses.end(), 21694e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling std::back_inserter(Uses)); 217eb18812f755b634f3e7554c1912aeb2d7476cb53Evan Cheng 21894e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // Now replace all uses. 21994e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling bool Changed = false; 22094e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (!Uses.empty()) { 22194e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling SmallPtrSet<MachineBasicBlock*, 4> PHIBBs; 2226cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling 22394e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // Look for PHI uses of the extended result, we don't want to extend the 22494e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // liveness of a PHI input. It breaks all kinds of assumptions down 22594e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling // stream. A PHI use is expected to be the kill of its source values. 22694e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling UI = MRI->use_nodbg_begin(DstReg); 2276cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling for (MachineRegisterInfo::use_nodbg_iterator 2286cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling UE = MRI->use_nodbg_end(); UI != UE; ++UI) 22994e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (UI->isPHI()) 23094e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling PHIBBs.insert(UI->getParent()); 231d64ba3ee62cc854218d9b76b9420493d82313d06Bill Wendling 23294e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling const TargetRegisterClass *RC = MRI->getRegClass(SrcReg); 23394e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling for (unsigned i = 0, e = Uses.size(); i != e; ++i) { 23494e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling MachineOperand *UseMO = Uses[i]; 23594e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling MachineInstr *UseMI = UseMO->getParent(); 236d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng MachineBasicBlock *UseMBB = UseMI->getParent(); 23794e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling if (PHIBBs.count(UseMBB)) 23894e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling continue; 2396cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling 240c69cbd0a7431b047dbc4a9758e81bf122926ba0aLang Hames // About to add uses of DstReg, clear DstReg's kill flags. 241c69cbd0a7431b047dbc4a9758e81bf122926ba0aLang Hames if (!Changed) 242c69cbd0a7431b047dbc4a9758e81bf122926ba0aLang Hames MRI->clearKillFlags(DstReg); 243c69cbd0a7431b047dbc4a9758e81bf122926ba0aLang Hames 24494e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling unsigned NewVR = MRI->createVirtualRegister(RC); 24594e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling BuildMI(*UseMBB, UseMI, UseMI->getDebugLoc(), 24694e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling TII->get(TargetOpcode::COPY), NewVR) 24794e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling .addReg(DstReg, 0, SubIdx); 2486cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling 24994e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling UseMO->setReg(NewVR); 25094e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling ++NumReuse; 25194e4008fbaa85600777b55605098bfd9cc3b9294Bill Wendling Changed = true; 252d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng } 253d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng } 254d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng 255d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng return Changed; 256d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng} 257d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng 25839cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach/// optimizeBitcastInstr - If the instruction is a bitcast instruction A that 259d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng/// cannot be optimized away during isel (e.g. ARM::VMOVSR, which bitcast 260d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng/// a value cross register classes), and the source is defined by another 261d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng/// bitcast instruction B. And if the register class of source of B matches 262d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng/// the register class of instruction A, then it is legal to replace all uses 263d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng/// of the def of A with source of B. e.g. 264d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng/// %vreg0<def> = VMOVSR %vreg1 265d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng/// %vreg3<def> = VMOVRS %vreg0 266d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng/// Replace all uses of vreg3 with vreg1. 267d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng 26839cc5138707eee563db7a487cd720b232b4b58fdJim Grosbachbool PeepholeOptimizer::optimizeBitcastInstr(MachineInstr *MI, 269d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng MachineBasicBlock *MBB) { 270d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng unsigned NumDefs = MI->getDesc().getNumDefs(); 271d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng unsigned NumSrcs = MI->getDesc().getNumOperands() - NumDefs; 272d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng if (NumDefs != 1) 273d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng return false; 274d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng 275d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng unsigned Def = 0; 276d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng unsigned Src = 0; 277d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng for (unsigned i = 0, e = NumDefs + NumSrcs; i != e; ++i) { 278d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng const MachineOperand &MO = MI->getOperand(i); 279d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng if (!MO.isReg()) 280d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng continue; 281d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng unsigned Reg = MO.getReg(); 282d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng if (!Reg) 283d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng continue; 284d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng if (MO.isDef()) 285d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng Def = Reg; 286d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng else if (Src) 287d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng // Multiple sources? 288d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng return false; 289d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng else 290d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng Src = Reg; 291d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng } 292d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng 293d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng assert(Def && Src && "Malformed bitcast instruction!"); 294d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng 295d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng MachineInstr *DefMI = MRI->getVRegDef(Src); 2965a96b3dad2f634c9081c8b2b6c2575441dc5a2bdEvan Cheng if (!DefMI || !DefMI->isBitcast()) 297d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng return false; 298d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng 299d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng unsigned SrcSrc = 0; 300d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng NumDefs = DefMI->getDesc().getNumDefs(); 301d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng NumSrcs = DefMI->getDesc().getNumOperands() - NumDefs; 302d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng if (NumDefs != 1) 303d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng return false; 304d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng for (unsigned i = 0, e = NumDefs + NumSrcs; i != e; ++i) { 305d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng const MachineOperand &MO = DefMI->getOperand(i); 306d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng if (!MO.isReg() || MO.isDef()) 307d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng continue; 308d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng unsigned Reg = MO.getReg(); 309d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng if (!Reg) 310d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng continue; 3117becbc41ab2875153868c21a84153eca442cc28fDuncan Sands if (!MO.isDef()) { 3127becbc41ab2875153868c21a84153eca442cc28fDuncan Sands if (SrcSrc) 3137becbc41ab2875153868c21a84153eca442cc28fDuncan Sands // Multiple sources? 3147becbc41ab2875153868c21a84153eca442cc28fDuncan Sands return false; 3157becbc41ab2875153868c21a84153eca442cc28fDuncan Sands else 3167becbc41ab2875153868c21a84153eca442cc28fDuncan Sands SrcSrc = Reg; 3177becbc41ab2875153868c21a84153eca442cc28fDuncan Sands } 318d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng } 319d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng 320d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng if (MRI->getRegClass(SrcSrc) != MRI->getRegClass(Def)) 321d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng return false; 322d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng 323d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng MRI->replaceRegWith(Def, SrcSrc); 324d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng MRI->clearKillFlags(SrcSrc); 325d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng MI->eraseFromParent(); 326d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng ++NumBitcasts; 327d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng return true; 328d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng} 329d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng 33039cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach/// optimizeCmpInstr - If the instruction is a compare and the previous 3316cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling/// instruction it's comparing against all ready sets (or could be modified to 3326cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling/// set) the same flag as the compare, then we can remove the comparison and use 3336cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling/// the flag from the previous instruction. 33439cc5138707eee563db7a487cd720b232b4b58fdJim Grosbachbool PeepholeOptimizer::optimizeCmpInstr(MachineInstr *MI, 335d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng MachineBasicBlock *MBB) { 3366cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling // If this instruction is a comparison against zero and isn't comparing a 3376cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling // physical register, we can try to optimize it. 3386cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling unsigned SrcReg; 33904ac81d5db058a3a9492e1aff1f398a8643bfda9Gabor Greif int CmpMask, CmpValue; 34004ac81d5db058a3a9492e1aff1f398a8643bfda9Gabor Greif if (!TII->AnalyzeCompare(MI, SrcReg, CmpMask, CmpValue) || 34192ad57f066e9f256e4e3d72febf152e68caa80c7Bill Wendling TargetRegisterInfo::isPhysicalRegister(SrcReg)) 3426cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling return false; 3436cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling 344a65568676d0d9d53dd4aae8f1c58271bb4cfff10Bill Wendling // Attempt to optimize the comparison instruction. 345eb96a2f6c03c0ec97c56a3493ac38024afacc774Evan Cheng if (TII->OptimizeCompareInstr(MI, SrcReg, CmpMask, CmpValue, MRI)) { 346d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng ++NumCmps; 3476cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling return true; 3486cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling } 3496cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling 3506cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling return false; 3516cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling} 3526cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling 353c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Chengbool PeepholeOptimizer::isMoveImmediate(MachineInstr *MI, 354c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng SmallSet<unsigned, 4> &ImmDefRegs, 355c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng DenseMap<unsigned, MachineInstr*> &ImmDefMIs) { 356e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng const MCInstrDesc &MCID = MI->getDesc(); 3575a96b3dad2f634c9081c8b2b6c2575441dc5a2bdEvan Cheng if (!MI->isMoveImmediate()) 358c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng return false; 359e837dead3c8dc3445ef6a0e2322179c57e264a13Evan Cheng if (MCID.getNumDefs() != 1) 360c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng return false; 361c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng unsigned Reg = MI->getOperand(0).getReg(); 362c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng if (TargetRegisterInfo::isVirtualRegister(Reg)) { 363c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng ImmDefMIs.insert(std::make_pair(Reg, MI)); 364c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng ImmDefRegs.insert(Reg); 365c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng return true; 366c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng } 3671df91b0e54bc62f8fc7a06a4f75220e40aa2dfe0Andrew Trick 368c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng return false; 369c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng} 370c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng 37139cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach/// foldImmediate - Try folding register operands that are defined by move 372c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng/// immediate instructions, i.e. a trivial constant folding optimization, if 373c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng/// and only if the def and use are in the same BB. 37439cc5138707eee563db7a487cd720b232b4b58fdJim Grosbachbool PeepholeOptimizer::foldImmediate(MachineInstr *MI, MachineBasicBlock *MBB, 375c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng SmallSet<unsigned, 4> &ImmDefRegs, 376c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng DenseMap<unsigned, MachineInstr*> &ImmDefMIs) { 377c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng for (unsigned i = 0, e = MI->getDesc().getNumOperands(); i != e; ++i) { 378c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng MachineOperand &MO = MI->getOperand(i); 379c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng if (!MO.isReg() || MO.isDef()) 380c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng continue; 381c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng unsigned Reg = MO.getReg(); 382c9df025e33ac435adb3b3318d237c36ca7cec659Jakob Stoklund Olesen if (!TargetRegisterInfo::isVirtualRegister(Reg)) 383c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng continue; 384c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng if (ImmDefRegs.count(Reg) == 0) 385c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng continue; 386c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng DenseMap<unsigned, MachineInstr*>::iterator II = ImmDefMIs.find(Reg); 387c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng assert(II != ImmDefMIs.end()); 388c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng if (TII->FoldImmediate(MI, II->second, Reg, MRI)) { 389c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng ++NumImmFold; 390c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng return true; 391c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng } 392c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng } 393c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng return false; 394c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng} 395c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng 3966cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendlingbool PeepholeOptimizer::runOnMachineFunction(MachineFunction &MF) { 397eb96a2f6c03c0ec97c56a3493ac38024afacc774Evan Cheng if (DisablePeephole) 398eb96a2f6c03c0ec97c56a3493ac38024afacc774Evan Cheng return false; 3991df91b0e54bc62f8fc7a06a4f75220e40aa2dfe0Andrew Trick 4006cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling TM = &MF.getTarget(); 4017da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng TII = TM->getInstrInfo(); 4027da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng MRI = &MF.getRegInfo(); 4036cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling DT = Aggressive ? &getAnalysis<MachineDominatorTree>() : 0; 4047da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng 4057da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng bool Changed = false; 4067da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng 4077da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng SmallPtrSet<MachineInstr*, 8> LocalMIs; 408c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng SmallSet<unsigned, 4> ImmDefRegs; 409c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng DenseMap<unsigned, MachineInstr*> ImmDefMIs; 4107da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I) { 4117da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng MachineBasicBlock *MBB = &*I; 4121df91b0e54bc62f8fc7a06a4f75220e40aa2dfe0Andrew Trick 413c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng bool SeenMoveImm = false; 414d89d5180d12107a2cdffa179c213370db2e088d5Evan Cheng LocalMIs.clear(); 415c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng ImmDefRegs.clear(); 416c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng ImmDefMIs.clear(); 4176cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling 418326d976eb2b03d1f2b7537d7b90dff264fd84378Evan Cheng bool First = true; 419326d976eb2b03d1f2b7537d7b90dff264fd84378Evan Cheng MachineBasicBlock::iterator PMII; 4206cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling for (MachineBasicBlock::iterator 421220e240bdf3235252c2a1fc8fcc5d4b8e8117918Bill Wendling MII = I->begin(), MIE = I->end(); MII != MIE; ) { 422cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng MachineInstr *MI = &*MII; 423eb96a2f6c03c0ec97c56a3493ac38024afacc774Evan Cheng LocalMIs.insert(MI); 424eb96a2f6c03c0ec97c56a3493ac38024afacc774Evan Cheng 42530a343aeedf777f9b8b6be9823da750afbf765b1Evan Cheng if (MI->isLabel() || MI->isPHI() || MI->isImplicitDef() || 42630a343aeedf777f9b8b6be9823da750afbf765b1Evan Cheng MI->isKill() || MI->isInlineAsm() || MI->isDebugValue() || 427cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng MI->hasUnmodeledSideEffects()) { 428cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng ++MII; 429eb96a2f6c03c0ec97c56a3493ac38024afacc774Evan Cheng continue; 430cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng } 431eb96a2f6c03c0ec97c56a3493ac38024afacc774Evan Cheng 4325a96b3dad2f634c9081c8b2b6c2575441dc5a2bdEvan Cheng if (MI->isBitcast()) { 43339cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach if (optimizeBitcastInstr(MI, MBB)) { 434d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng // MI is deleted. 435dec1b10161a3bc1b49ab8d35e1bd6488486dfd4aNick Lewycky LocalMIs.erase(MI); 436d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng Changed = true; 437d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng MII = First ? I->begin() : llvm::next(PMII); 438d158fba3e45547f013bbab4c0ac640f31b5e341fEvan Cheng continue; 4391df91b0e54bc62f8fc7a06a4f75220e40aa2dfe0Andrew Trick } 4405a96b3dad2f634c9081c8b2b6c2575441dc5a2bdEvan Cheng } else if (MI->isCompare()) { 44139cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach if (optimizeCmpInstr(MI, MBB)) { 442cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng // MI is deleted. 443dec1b10161a3bc1b49ab8d35e1bd6488486dfd4aNick Lewycky LocalMIs.erase(MI); 444cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng Changed = true; 445326d976eb2b03d1f2b7537d7b90dff264fd84378Evan Cheng MII = First ? I->begin() : llvm::next(PMII); 446cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng continue; 447cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng } 448cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng } 449cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng 450cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng if (isMoveImmediate(MI, ImmDefRegs, ImmDefMIs)) { 451c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng SeenMoveImm = true; 4526cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling } else { 45339cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach Changed |= optimizeExtInstr(MI, MBB, LocalMIs); 454c4af4638dfdab0dc3b6257276cfad2ee45053060Evan Cheng if (SeenMoveImm) 45539cc5138707eee563db7a487cd720b232b4b58fdJim Grosbach Changed |= foldImmediate(MI, MBB, ImmDefRegs, ImmDefMIs); 4566cdb1abe4e4f6364649e7ef656589441754e82aeBill Wendling } 457326d976eb2b03d1f2b7537d7b90dff264fd84378Evan Cheng 458326d976eb2b03d1f2b7537d7b90dff264fd84378Evan Cheng First = false; 459cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng PMII = MII; 460cf75ab597514effb6f8e915f05d74f45debb89ecEvan Cheng ++MII; 4617da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng } 4627da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng } 4637da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng 4647da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng return Changed; 4657da9ecf9677b751d81515f95168ae3cb2df54160Evan Cheng} 466