X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FBranchFolding.cpp;h=fe8baeabc463baca04c4faaea63e234e30f117cb;hb=3bfc4d8e13edd83534b733f0f1de5b1d5f6bf828;hp=793e4f07063680488a5241d9e6e456243a3a3c48;hpb=c16c25fbc3b53da99dcaf27685a6116249f79b30;p=oota-llvm.git diff --git a/lib/CodeGen/BranchFolding.cpp b/lib/CodeGen/BranchFolding.cpp index 793e4f07063..fe8baeabc46 100644 --- a/lib/CodeGen/BranchFolding.cpp +++ b/lib/CodeGen/BranchFolding.cpp @@ -18,23 +18,23 @@ #define DEBUG_TYPE "branchfolding" #include "BranchFolding.h" -#include "llvm/Function.h" -#include "llvm/CodeGen/Passes.h" -#include "llvm/CodeGen/MachineModuleInfo.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/SmallSet.h" +#include "llvm/ADT/Statistic.h" #include "llvm/CodeGen/MachineFunctionPass.h" #include "llvm/CodeGen/MachineJumpTableInfo.h" +#include "llvm/CodeGen/MachineModuleInfo.h" +#include "llvm/CodeGen/MachineRegisterInfo.h" +#include "llvm/CodeGen/Passes.h" #include "llvm/CodeGen/RegisterScavenging.h" -#include "llvm/Target/TargetInstrInfo.h" -#include "llvm/Target/TargetMachine.h" -#include "llvm/Target/TargetRegisterInfo.h" +#include "llvm/IR/Function.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/raw_ostream.h" -#include "llvm/ADT/SmallSet.h" -#include "llvm/ADT/SetVector.h" -#include "llvm/ADT/Statistic.h" -#include "llvm/ADT/STLExtras.h" +#include "llvm/Target/TargetInstrInfo.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetRegisterInfo.h" #include using namespace llvm; @@ -61,29 +61,37 @@ TailMergeSize("tail-merge-size", namespace { /// BranchFolderPass - Wrap branch folder in a machine function pass. - class BranchFolderPass : public MachineFunctionPass, - public BranchFolder { + class BranchFolderPass : public MachineFunctionPass { public: static char ID; - explicit BranchFolderPass(bool defaultEnableTailMerge) - : MachineFunctionPass(ID), BranchFolder(defaultEnableTailMerge, true) {} + explicit BranchFolderPass(): MachineFunctionPass(ID) {} - virtual bool runOnMachineFunction(MachineFunction &MF); - virtual const char *getPassName() const { return "Control Flow Optimizer"; } + bool runOnMachineFunction(MachineFunction &MF) override; + + void getAnalysisUsage(AnalysisUsage &AU) const override { + AU.addRequired(); + MachineFunctionPass::getAnalysisUsage(AU); + } }; } char BranchFolderPass::ID = 0; +char &llvm::BranchFolderPassID = BranchFolderPass::ID; -FunctionPass *llvm::createBranchFoldingPass(bool DefaultEnableTailMerge) { - return new BranchFolderPass(DefaultEnableTailMerge); -} +INITIALIZE_PASS(BranchFolderPass, "branch-folder", + "Control Flow Optimizer", false, false) bool BranchFolderPass::runOnMachineFunction(MachineFunction &MF) { - return OptimizeFunction(MF, - MF.getTarget().getInstrInfo(), - MF.getTarget().getRegisterInfo(), - getAnalysisIfAvailable()); + TargetPassConfig *PassConfig = &getAnalysis(); + // TailMerge can create jump into if branches that make CFG irreducible for + // HW that requires structurized CFG. + bool EnableTailMerge = !MF.getTarget().requiresStructuredCFG() && + PassConfig->getEnableTailMerge(); + BranchFolder Folder(EnableTailMerge, /*CommonHoist=*/true); + return Folder.OptimizeFunction(MF, + MF.getTarget().getInstrInfo(), + MF.getTarget().getRegisterInfo(), + getAnalysisIfAvailable()); } @@ -131,10 +139,9 @@ bool BranchFolder::OptimizeImpDefsBlock(MachineBasicBlock *MBB) { if (!I->isImplicitDef()) break; unsigned Reg = I->getOperand(0).getReg(); - ImpDefRegs.insert(Reg); - for (const unsigned *SubRegs = TRI->getSubRegisters(Reg); - unsigned SubReg = *SubRegs; ++SubRegs) - ImpDefRegs.insert(SubReg); + for (MCSubRegIterator SubRegs(Reg, TRI, /*IncludeSelf=*/true); + SubRegs.isValid(); ++SubRegs) + ImpDefRegs.insert(*SubRegs); ++I; } if (ImpDefRegs.empty()) @@ -179,8 +186,14 @@ bool BranchFolder::OptimizeFunction(MachineFunction &MF, TII = tii; TRI = tri; MMI = mmi; + RS = NULL; - RS = TRI->requiresRegisterScavenging(MF) ? new RegScavenger() : NULL; + // Use a RegScavenger to help update liveness when required. + MachineRegisterInfo &MRI = MF.getRegInfo(); + if (MRI.tracksLiveness() && TRI->trackLivenessAfterRegAlloc(MF)) + RS = new RegScavenger(); + else + MRI.invalidateLiveness(); // Fix CFG. The later algorithms expect it to be right. bool MadeChange = false; @@ -208,7 +221,7 @@ bool BranchFolder::OptimizeFunction(MachineFunction &MF, delete RS; return MadeChange; } - + // Walk the function to find jump tables that are live. BitVector JTIsLive(JTI->getJumpTables().size()); for (MachineFunction::iterator BB = MF.begin(), E = MF.end(); @@ -347,9 +360,8 @@ static unsigned ComputeCommonTailLength(MachineBasicBlock *MBB1, if (I1 == MBB1->begin() && I2 != MBB2->begin()) { --I2; while (I2->isDebugValue()) { - if (I2 == MBB2->begin()) { + if (I2 == MBB2->begin()) return TailLen; - } --I2; } ++I2; @@ -371,7 +383,7 @@ void BranchFolder::MaintainLiveIns(MachineBasicBlock *CurMBB, if (RS) { RS->enterBasicBlock(CurMBB); if (!CurMBB->empty()) - RS->forward(prior(CurMBB->end())); + RS->forward(std::prev(CurMBB->end())); BitVector RegsLiveAtExit(TRI->getNumRegs()); RS->getRegsUsed(RegsLiveAtExit, false); for (unsigned int i = 0, e = TRI->getNumRegs(); i != e; i++) @@ -398,7 +410,8 @@ void BranchFolder::ReplaceTailWithBranchTo(MachineBasicBlock::iterator OldInst, /// MBB so that the part before the iterator falls into the part starting at the /// iterator. This returns the new MBB. MachineBasicBlock *BranchFolder::SplitMBBAt(MachineBasicBlock &CurMBB, - MachineBasicBlock::iterator BBI1) { + MachineBasicBlock::iterator BBI1, + const BasicBlock *BB) { if (!TII->isLegalToSplitMBBAt(CurMBB, BBI1)) return 0; @@ -406,7 +419,7 @@ MachineBasicBlock *BranchFolder::SplitMBBAt(MachineBasicBlock &CurMBB, // Create the fall-through block. MachineFunction::iterator MBBI = &CurMBB; - MachineBasicBlock *NewMBB =MF.CreateMachineBasicBlock(CurMBB.getBasicBlock()); + MachineBasicBlock *NewMBB =MF.CreateMachineBasicBlock(BB); CurMBB.getParent()->insert(++MBBI, NewMBB); // Move all the successors of this block to the specified block. @@ -449,7 +462,7 @@ static unsigned EstimateRuntime(MachineBasicBlock::iterator I, static void FixTail(MachineBasicBlock *CurMBB, MachineBasicBlock *SuccBB, const TargetInstrInfo *TII) { MachineFunction *MF = CurMBB->getParent(); - MachineFunction::iterator I = llvm::next(MachineFunction::iterator(CurMBB)); + MachineFunction::iterator I = std::next(MachineFunction::iterator(CurMBB)); MachineBasicBlock *TBB = 0, *FBB = 0; SmallVector Cond; DebugLoc dl; // FIXME: this is nowhere @@ -472,20 +485,19 @@ bool BranchFolder::MergePotentialsElt::operator<(const MergePotentialsElt &o) const { if (getHash() < o.getHash()) return true; - else if (getHash() > o.getHash()) + if (getHash() > o.getHash()) return false; - else if (getBlock()->getNumber() < o.getBlock()->getNumber()) + if (getBlock()->getNumber() < o.getBlock()->getNumber()) return true; - else if (getBlock()->getNumber() > o.getBlock()->getNumber()) + if (getBlock()->getNumber() > o.getBlock()->getNumber()) return false; - else { - // _GLIBCXX_DEBUG checks strict weak ordering, which involves comparing - // an object with itself. + // _GLIBCXX_DEBUG checks strict weak ordering, which involves comparing + // an object with itself. #ifndef _GLIBCXX_DEBUG - llvm_unreachable("Predecessor appears twice"); + llvm_unreachable("Predecessor appears twice"); +#else + return false; #endif - return false; - } } /// CountTerminators - Count the number of terminators in the given @@ -563,7 +575,8 @@ static bool ProfitableToMerge(MachineBasicBlock *MBB1, // instructions that would be deleted in the merge. MachineFunction *MF = MBB1->getParent(); if (EffectiveTailLen >= 2 && - MF->getFunction()->hasFnAttr(Attribute::OptimizeForSize) && + MF->getFunction()->getAttributes(). + hasAttribute(AttributeSet::FunctionIndex, Attribute::OptimizeForSize) && (I1 == MBB1->begin() || I2 == MBB2->begin())) return true; @@ -587,12 +600,11 @@ unsigned BranchFolder::ComputeSameTails(unsigned CurHash, unsigned maxCommonTailLength = 0U; SameTails.clear(); MachineBasicBlock::iterator TrialBBI1, TrialBBI2; - MPIterator HighestMPIter = prior(MergePotentials.end()); - for (MPIterator CurMPIter = prior(MergePotentials.end()), + MPIterator HighestMPIter = std::prev(MergePotentials.end()); + for (MPIterator CurMPIter = std::prev(MergePotentials.end()), B = MergePotentials.begin(); - CurMPIter != B && CurMPIter->getHash() == CurHash; - --CurMPIter) { - for (MPIterator I = prior(CurMPIter); I->getHash() == CurHash ; --I) { + CurMPIter != B && CurMPIter->getHash() == CurHash; --CurMPIter) { + for (MPIterator I = std::prev(CurMPIter); I->getHash() == CurHash; --I) { unsigned CommonTailLen; if (ProfitableToMerge(CurMPIter->getBlock(), I->getBlock(), minCommonTailLength, @@ -621,9 +633,9 @@ void BranchFolder::RemoveBlocksWithHash(unsigned CurHash, MachineBasicBlock *SuccBB, MachineBasicBlock *PredBB) { MPIterator CurMPIter, B; - for (CurMPIter = prior(MergePotentials.end()), B = MergePotentials.begin(); - CurMPIter->getHash() == CurHash; - --CurMPIter) { + for (CurMPIter = std::prev(MergePotentials.end()), + B = MergePotentials.begin(); + CurMPIter->getHash() == CurHash; --CurMPIter) { // Put the unconditional branch back, if we need one. MachineBasicBlock *CurMBB = CurMPIter->getBlock(); if (SuccBB && CurMBB != PredBB) @@ -639,6 +651,7 @@ void BranchFolder::RemoveBlocksWithHash(unsigned CurHash, /// CreateCommonTailOnlyBlock - None of the blocks to be tail-merged consist /// only of the common tail. Create a block that does by splitting one. bool BranchFolder::CreateCommonTailOnlyBlock(MachineBasicBlock *&PredBB, + MachineBasicBlock *SuccBB, unsigned maxCommonTailLength, unsigned &commonTailIndex) { commonTailIndex = 0; @@ -668,7 +681,12 @@ bool BranchFolder::CreateCommonTailOnlyBlock(MachineBasicBlock *&PredBB, DEBUG(dbgs() << "\nSplitting BB#" << MBB->getNumber() << ", size " << maxCommonTailLength); - MachineBasicBlock *newMBB = SplitMBBAt(*MBB, BBI); + // If the split block unconditionally falls-thru to SuccBB, it will be + // merged. In control flow terms it should then take SuccBB's name. e.g. If + // SuccBB is an inner loop, the common tail is still part of the inner loop. + const BasicBlock *BB = (SuccBB && MBB->succ_size() == 1) ? + SuccBB->getBasicBlock() : MBB->getBasicBlock(); + MachineBasicBlock *newMBB = SplitMBBAt(*MBB, BBI, BB); if (!newMBB) { DEBUG(dbgs() << "... failed!"); return false; @@ -776,7 +794,7 @@ bool BranchFolder::TryTailMergeBlocks(MachineBasicBlock *SuccBB, !SameTails[commonTailIndex].tailIsWholeBlock())) { // None of the blocks consist entirely of the common tail. // Split a block so that one does. - if (!CreateCommonTailOnlyBlock(PredBB, + if (!CreateCommonTailOnlyBlock(PredBB, SuccBB, maxCommonTailLength, commonTailIndex)) { RemoveBlocksWithHash(CurHash, SuccBB, PredBB); continue; @@ -807,10 +825,8 @@ bool BranchFolder::TryTailMergeBlocks(MachineBasicBlock *SuccBB, } bool BranchFolder::TailMergeBlocks(MachineFunction &MF) { - - if (!EnableTailMerge) return false; - bool MadeChange = false; + if (!EnableTailMerge) return MadeChange; // First find blocks with no successors. MergePotentials.clear(); @@ -827,6 +843,7 @@ bool BranchFolder::TailMergeBlocks(MachineFunction &MF) { if (MergePotentials.size() == TailMergeThreshold) for (unsigned i = 0, e = MergePotentials.size(); i != e; ++i) TriedMerging.insert(MergePotentials[i].getBlock()); + // See if we can do any tail merging on those. if (MergePotentials.size() >= 2) MadeChange |= TryTailMergeBlocks(NULL, NULL); @@ -850,90 +867,99 @@ bool BranchFolder::TailMergeBlocks(MachineFunction &MF) { // a compile-time infinite loop repeatedly doing and undoing the same // transformations.) - for (MachineFunction::iterator I = llvm::next(MF.begin()), E = MF.end(); + for (MachineFunction::iterator I = std::next(MF.begin()), E = MF.end(); I != E; ++I) { - if (I->pred_size() >= 2) { - SmallPtrSet UniquePreds; - MachineBasicBlock *IBB = I; - MachineBasicBlock *PredBB = prior(I); - MergePotentials.clear(); - for (MachineBasicBlock::pred_iterator P = I->pred_begin(), - E2 = I->pred_end(); - P != E2 && MergePotentials.size() < TailMergeThreshold; ++P) { - MachineBasicBlock *PBB = *P; - if (TriedMerging.count(PBB)) - continue; - // Skip blocks that loop to themselves, can't tail merge these. - if (PBB == IBB) - continue; - // Visit each predecessor only once. - if (!UniquePreds.insert(PBB)) - continue; - // Skip blocks which may jump to a landing pad. Can't tail merge these. - if (PBB->getLandingPadSuccessor()) - continue; - MachineBasicBlock *TBB = 0, *FBB = 0; - SmallVector Cond; - if (!TII->AnalyzeBranch(*PBB, TBB, FBB, Cond, true)) { - // Failing case: IBB is the target of a cbr, and - // we cannot reverse the branch. - SmallVector NewCond(Cond); - if (!Cond.empty() && TBB == IBB) { - if (TII->ReverseBranchCondition(NewCond)) + if (I->pred_size() < 2) continue; + SmallPtrSet UniquePreds; + MachineBasicBlock *IBB = I; + MachineBasicBlock *PredBB = std::prev(I); + MergePotentials.clear(); + for (MachineBasicBlock::pred_iterator P = I->pred_begin(), + E2 = I->pred_end(); + P != E2 && MergePotentials.size() < TailMergeThreshold; ++P) { + MachineBasicBlock *PBB = *P; + if (TriedMerging.count(PBB)) + continue; + + // Skip blocks that loop to themselves, can't tail merge these. + if (PBB == IBB) + continue; + + // Visit each predecessor only once. + if (!UniquePreds.insert(PBB)) + continue; + + // Skip blocks which may jump to a landing pad. Can't tail merge these. + if (PBB->getLandingPadSuccessor()) + continue; + + MachineBasicBlock *TBB = 0, *FBB = 0; + SmallVector Cond; + if (!TII->AnalyzeBranch(*PBB, TBB, FBB, Cond, true)) { + // Failing case: IBB is the target of a cbr, and we cannot reverse the + // branch. + SmallVector NewCond(Cond); + if (!Cond.empty() && TBB == IBB) { + if (TII->ReverseBranchCondition(NewCond)) + continue; + // This is the QBB case described above + if (!FBB) + FBB = std::next(MachineFunction::iterator(PBB)); + } + + // Failing case: the only way IBB can be reached from PBB is via + // exception handling. Happens for landing pads. Would be nice to have + // a bit in the edge so we didn't have to do all this. + if (IBB->isLandingPad()) { + MachineFunction::iterator IP = PBB; IP++; + MachineBasicBlock *PredNextBB = NULL; + if (IP != MF.end()) + PredNextBB = IP; + if (TBB == NULL) { + if (IBB != PredNextBB) // fallthrough + continue; + } else if (FBB) { + if (TBB != IBB && FBB != IBB) // cbr then ubr + continue; + } else if (Cond.empty()) { + if (TBB != IBB) // ubr + continue; + } else { + if (TBB != IBB && IBB != PredNextBB) // cbr continue; - // This is the QBB case described above - if (!FBB) - FBB = llvm::next(MachineFunction::iterator(PBB)); - } - // Failing case: the only way IBB can be reached from PBB is via - // exception handling. Happens for landing pads. Would be nice - // to have a bit in the edge so we didn't have to do all this. - if (IBB->isLandingPad()) { - MachineFunction::iterator IP = PBB; IP++; - MachineBasicBlock *PredNextBB = NULL; - if (IP != MF.end()) - PredNextBB = IP; - if (TBB == NULL) { - if (IBB != PredNextBB) // fallthrough - continue; - } else if (FBB) { - if (TBB != IBB && FBB != IBB) // cbr then ubr - continue; - } else if (Cond.empty()) { - if (TBB != IBB) // ubr - continue; - } else { - if (TBB != IBB && IBB != PredNextBB) // cbr - continue; - } - } - // Remove the unconditional branch at the end, if any. - if (TBB && (Cond.empty() || FBB)) { - DebugLoc dl; // FIXME: this is nowhere - TII->RemoveBranch(*PBB); - if (!Cond.empty()) - // reinsert conditional branch only, for now - TII->InsertBranch(*PBB, (TBB == IBB) ? FBB : TBB, 0, NewCond, dl); } - MergePotentials.push_back(MergePotentialsElt(HashEndOfMBB(PBB), *P)); } + + // Remove the unconditional branch at the end, if any. + if (TBB && (Cond.empty() || FBB)) { + DebugLoc dl; // FIXME: this is nowhere + TII->RemoveBranch(*PBB); + if (!Cond.empty()) + // reinsert conditional branch only, for now + TII->InsertBranch(*PBB, (TBB == IBB) ? FBB : TBB, 0, NewCond, dl); + } + + MergePotentials.push_back(MergePotentialsElt(HashEndOfMBB(PBB), *P)); } - // If this is a large problem, avoid visiting the same basic blocks - // multiple times. - if (MergePotentials.size() == TailMergeThreshold) - for (unsigned i = 0, e = MergePotentials.size(); i != e; ++i) - TriedMerging.insert(MergePotentials[i].getBlock()); - if (MergePotentials.size() >= 2) - MadeChange |= TryTailMergeBlocks(IBB, PredBB); - // Reinsert an unconditional branch if needed. - // The 1 below can occur as a result of removing blocks in - // TryTailMergeBlocks. - PredBB = prior(I); // this may have been changed in TryTailMergeBlocks - if (MergePotentials.size() == 1 && - MergePotentials.begin()->getBlock() != PredBB) - FixTail(MergePotentials.begin()->getBlock(), IBB, TII); } + + // If this is a large problem, avoid visiting the same basic blocks multiple + // times. + if (MergePotentials.size() == TailMergeThreshold) + for (unsigned i = 0, e = MergePotentials.size(); i != e; ++i) + TriedMerging.insert(MergePotentials[i].getBlock()); + + if (MergePotentials.size() >= 2) + MadeChange |= TryTailMergeBlocks(IBB, PredBB); + + // Reinsert an unconditional branch if needed. The 1 below can occur as a + // result of removing blocks in TryTailMergeBlocks. + PredBB = std::prev(I); // this may have been changed in TryTailMergeBlocks + if (MergePotentials.size() == 1 && + MergePotentials.begin()->getBlock() != PredBB) + FixTail(MergePotentials.begin()->getBlock(), IBB, TII); } + return MadeChange; } @@ -947,7 +973,7 @@ bool BranchFolder::OptimizeBranches(MachineFunction &MF) { // Make sure blocks are numbered in order MF.RenumberBlocks(); - for (MachineFunction::iterator I = llvm::next(MF.begin()), E = MF.end(); + for (MachineFunction::iterator I = std::next(MF.begin()), E = MF.end(); I != E; ) { MachineBasicBlock *MBB = I++; MadeChange |= OptimizeBlock(MBB); @@ -1014,12 +1040,27 @@ static bool IsBetterFallthrough(MachineBasicBlock *MBB1, return MBB2I->isCall() && !MBB1I->isCall(); } +/// getBranchDebugLoc - Find and return, if any, the DebugLoc of the branch +/// instructions on the block. Always use the DebugLoc of the first +/// branching instruction found unless its absent, in which case use the +/// DebugLoc of the second if present. +static DebugLoc getBranchDebugLoc(MachineBasicBlock &MBB) { + MachineBasicBlock::iterator I = MBB.end(); + if (I == MBB.begin()) + return DebugLoc(); + --I; + while (I->isDebugValue() && I != MBB.begin()) + --I; + if (I->isBranch()) + return I->getDebugLoc(); + return DebugLoc(); +} + /// OptimizeBlock - Analyze and optimize control flow related to the specified /// block. This is never called on the entry block. bool BranchFolder::OptimizeBlock(MachineBasicBlock *MBB) { bool MadeChange = false; MachineFunction &MF = *MBB->getParent(); - DebugLoc dl; // FIXME: this is nowhere ReoptimizeBlock: MachineFunction::iterator FallThrough = MBB; @@ -1053,7 +1094,7 @@ ReoptimizeBlock: // Check to see if we can simplify the terminator of the block before this // one. - MachineBasicBlock &PrevBB = *prior(MachineFunction::iterator(MBB)); + MachineBasicBlock &PrevBB = *std::prev(MachineFunction::iterator(MBB)); MachineBasicBlock *PriorTBB = 0, *PriorFBB = 0; SmallVector PriorCond; @@ -1068,6 +1109,7 @@ ReoptimizeBlock: // destination, remove the branch, replacing it with an unconditional one or // a fall-through. if (PriorTBB && PriorTBB == PriorFBB) { + DebugLoc dl = getBranchDebugLoc(PrevBB); TII->RemoveBranch(PrevBB); PriorCond.clear(); if (PriorTBB != MBB) @@ -1094,7 +1136,7 @@ ReoptimizeBlock: MachineBasicBlock::iterator PrevBBIter = PrevBB.end(); --PrevBBIter; MachineBasicBlock::iterator MBBIter = MBB->begin(); - // Check if DBG_VALUE at the end of PrevBB is identical to the + // Check if DBG_VALUE at the end of PrevBB is identical to the // DBG_VALUE at the beginning of MBB. while (PrevBBIter != PrevBB.begin() && MBBIter != MBB->end() && PrevBBIter->isDebugValue() && MBBIter->isDebugValue()) { @@ -1106,7 +1148,7 @@ ReoptimizeBlock: } } PrevBB.splice(PrevBB.end(), MBB, MBB->begin(), MBB->end()); - PrevBB.removeSuccessor(PrevBB.succ_begin());; + PrevBB.removeSuccessor(PrevBB.succ_begin()); assert(PrevBB.succ_empty()); PrevBB.transferSuccessors(MBB); MadeChange = true; @@ -1125,6 +1167,7 @@ ReoptimizeBlock: // If the prior block branches somewhere else on the condition and here if // the condition is false, remove the uncond second branch. if (PriorFBB == MBB) { + DebugLoc dl = getBranchDebugLoc(PrevBB); TII->RemoveBranch(PrevBB); TII->InsertBranch(PrevBB, PriorTBB, 0, PriorCond, dl); MadeChange = true; @@ -1138,6 +1181,7 @@ ReoptimizeBlock: if (PriorTBB == MBB) { SmallVector NewPriorCond(PriorCond); if (!TII->ReverseBranchCondition(NewPriorCond)) { + DebugLoc dl = getBranchDebugLoc(PrevBB); TII->RemoveBranch(PrevBB); TII->InsertBranch(PrevBB, PriorFBB, 0, NewPriorCond, dl); MadeChange = true; @@ -1175,6 +1219,7 @@ ReoptimizeBlock: DEBUG(dbgs() << "\nMoving MBB: " << *MBB << "To make fallthrough to: " << *PriorTBB << "\n"); + DebugLoc dl = getBranchDebugLoc(PrevBB); TII->RemoveBranch(PrevBB); TII->InsertBranch(PrevBB, MBB, 0, NewPriorCond, dl); @@ -1204,6 +1249,7 @@ ReoptimizeBlock: if (CurTBB && CurFBB && CurFBB == MBB && CurTBB != MBB) { SmallVector NewCond(CurCond); if (!TII->ReverseBranchCondition(NewCond)) { + DebugLoc dl = getBranchDebugLoc(*MBB); TII->RemoveBranch(*MBB); TII->InsertBranch(*MBB, CurFBB, CurTBB, NewCond, dl); MadeChange = true; @@ -1217,6 +1263,7 @@ ReoptimizeBlock: if (CurTBB && CurCond.empty() && CurFBB == 0 && IsBranchOnlyBlock(MBB) && CurTBB != MBB && !MBB->hasAddressTaken()) { + DebugLoc dl = getBranchDebugLoc(*MBB); // This block may contain just an unconditional branch. Because there can // be 'non-branch terminators' in the block, try removing the branch and // then seeing if the block is empty. @@ -1259,8 +1306,9 @@ ReoptimizeBlock: assert(PriorFBB == 0 && "Machine CFG out of date!"); PriorFBB = MBB; } + DebugLoc pdl = getBranchDebugLoc(PrevBB); TII->RemoveBranch(PrevBB); - TII->InsertBranch(PrevBB, PriorTBB, PriorFBB, PriorCond, dl); + TII->InsertBranch(PrevBB, PriorTBB, PriorFBB, PriorCond, pdl); } // Iterate through all the predecessors, revectoring each in-turn. @@ -1284,9 +1332,10 @@ ReoptimizeBlock: bool NewCurUnAnalyzable = TII->AnalyzeBranch(*PMBB, NewCurTBB, NewCurFBB, NewCurCond, true); if (!NewCurUnAnalyzable && NewCurTBB && NewCurTBB == NewCurFBB) { + DebugLoc pdl = getBranchDebugLoc(*PMBB); TII->RemoveBranch(*PMBB); NewCurCond.clear(); - TII->InsertBranch(*PMBB, NewCurTBB, 0, NewCurCond, dl); + TII->InsertBranch(*PMBB, NewCurTBB, 0, NewCurCond, pdl); MadeChange = true; ++NumBranchOpts; PMBB->CorrectExtraCFGEdges(NewCurTBB, 0, false); @@ -1344,9 +1393,10 @@ ReoptimizeBlock: // B elsewhere // next: if (CurFallsThru) { - MachineBasicBlock *NextBB = llvm::next(MachineFunction::iterator(MBB)); + MachineBasicBlock *NextBB = + std::next(MachineFunction::iterator(MBB)); CurCond.clear(); - TII->InsertBranch(*MBB, NextBB, 0, CurCond, dl); + TII->InsertBranch(*MBB, NextBB, 0, CurCond, DebugLoc()); } MBB->moveAfter(PredBB); MadeChange = true; @@ -1424,7 +1474,7 @@ static MachineBasicBlock *findFalseBlock(MachineBasicBlock *BB, } /// findHoistingInsertPosAndDeps - Find the location to move common instructions -/// in successors to. The location is ususally just before the terminator, +/// in successors to. The location is usually just before the terminator, /// however if the terminator is a conditional branch and its previous /// instruction is the flag setting instruction, the previous instruction is /// the preferred location. This function also gathers uses and defs of the @@ -1448,9 +1498,8 @@ MachineBasicBlock::iterator findHoistingInsertPosAndDeps(MachineBasicBlock *MBB, if (!Reg) continue; if (MO.isUse()) { - Uses.insert(Reg); - for (const unsigned *AS = TRI->getAliasSet(Reg); *AS; ++AS) - Uses.insert(*AS); + for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) + Uses.insert(*AI); } else if (!MO.isDead()) // Don't try to hoist code in the rare case the terminator defines a // register that is later used. @@ -1472,6 +1521,9 @@ MachineBasicBlock::iterator findHoistingInsertPosAndDeps(MachineBasicBlock *MBB, bool IsDef = false; for (unsigned i = 0, e = PI->getNumOperands(); !IsDef && i != e; ++i) { const MachineOperand &MO = PI->getOperand(i); + // If PI has a regmask operand, it is probably a call. Separate away. + if (MO.isRegMask()) + return Loc; if (!MO.isReg() || MO.isUse()) continue; unsigned Reg = MO.getReg(); @@ -1507,18 +1559,15 @@ MachineBasicBlock::iterator findHoistingInsertPosAndDeps(MachineBasicBlock *MBB, if (!Reg) continue; if (MO.isUse()) { - Uses.insert(Reg); - for (const unsigned *AS = TRI->getAliasSet(Reg); *AS; ++AS) - Uses.insert(*AS); + for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) + Uses.insert(*AI); } else { - if (Uses.count(Reg)) { - Uses.erase(Reg); - for (const unsigned *SR = TRI->getSubRegisters(Reg); *SR; ++SR) - Uses.erase(*SR); // Use getSubRegisters to be conservative + if (Uses.erase(Reg)) { + for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs) + Uses.erase(*SubRegs); // Use sub-registers to be conservative } - Defs.insert(Reg); - for (const unsigned *AS = TRI->getAliasSet(Reg); *AS; ++AS) - Defs.insert(*AS); + for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) + Defs.insert(*AI); } } @@ -1584,6 +1633,11 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) { bool IsSafe = true; for (unsigned i = 0, e = TIB->getNumOperands(); i != e; ++i) { MachineOperand &MO = TIB->getOperand(i); + // Don't attempt to hoist instructions with register masks. + if (MO.isRegMask()) { + IsSafe = false; + break; + } if (!MO.isReg()) continue; unsigned Reg = MO.getReg(); @@ -1640,8 +1694,8 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) { unsigned Reg = MO.getReg(); if (!Reg || !LocalDefsSet.count(Reg)) continue; - for (const unsigned *OR = TRI->getOverlaps(Reg); *OR; ++OR) - LocalDefsSet.erase(*OR); + for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) + LocalDefsSet.erase(*AI); } // Track local defs so we can update liveins. @@ -1653,11 +1707,11 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) { if (!Reg) continue; LocalDefs.push_back(Reg); - for (const unsigned *OR = TRI->getOverlaps(Reg); *OR; ++OR) - LocalDefsSet.insert(*OR); + for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) + LocalDefsSet.insert(*AI); } - HasDups = true;; + HasDups = true; ++TIB; ++FIB; }