X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FStackColoring.cpp;h=7b1de85baa7bf51328055870143bc9df4ae57a49;hb=fabe5ce5661e096114b6a4cc978d312a1f7a8e7f;hp=faaa6e73e4e704c7dbddcb2841775f3317dc3073;hpb=f22fd3f7b557a967b1edc1fa9ae770006a39e97c;p=oota-llvm.git diff --git a/lib/CodeGen/StackColoring.cpp b/lib/CodeGen/StackColoring.cpp index faaa6e73e4e..7b1de85baa7 100644 --- a/lib/CodeGen/StackColoring.cpp +++ b/lib/CodeGen/StackColoring.cpp @@ -30,7 +30,6 @@ #include "llvm/ADT/SmallPtrSet.h" #include "llvm/ADT/SparseSet.h" #include "llvm/ADT/Statistic.h" -#include "llvm/Analysis/Dominators.h" #include "llvm/Analysis/ValueTracking.h" #include "llvm/CodeGen/LiveInterval.h" #include "llvm/CodeGen/MachineBasicBlock.h" @@ -44,7 +43,9 @@ #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/PseudoSourceValue.h" #include "llvm/CodeGen/SlotIndexes.h" -#include "llvm/DebugInfo.h" +#include "llvm/CodeGen/StackProtector.h" +#include "llvm/IR/DebugInfo.h" +#include "llvm/IR/Dominators.h" #include "llvm/IR/Function.h" #include "llvm/IR/Instructions.h" #include "llvm/IR/Module.h" @@ -112,37 +113,25 @@ class StackColoring : public MachineFunctionPass { SmallVector BasicBlockNumbering; /// Maps liveness intervals for each slot. - SmallVector Intervals; + SmallVector, 16> Intervals; /// VNInfo is used for the construction of LiveIntervals. VNInfo::Allocator VNInfoAllocator; /// SlotIndex analysis object. SlotIndexes *Indexes; + /// The stack protector object. + StackProtector *SP; /// The list of lifetime markers found. These markers are to be removed /// once the coloring is done. SmallVector Markers; - /// SlotSizeSorter - A Sort utility for arranging stack slots according - /// to their size. - struct SlotSizeSorter { - MachineFrameInfo *MFI; - SlotSizeSorter(MachineFrameInfo *mfi) : MFI(mfi) { } - bool operator()(int LHS, int RHS) { - // We use -1 to denote a uninteresting slot. Place these slots at the end. - if (LHS == -1) return false; - if (RHS == -1) return true; - // Sort according to size. - return MFI->getObjectSize(LHS) > MFI->getObjectSize(RHS); - } -}; - public: static char ID; StackColoring() : MachineFunctionPass(ID) { initializeStackColoringPass(*PassRegistry::getPassRegistry()); } - void getAnalysisUsage(AnalysisUsage &AU) const; - bool runOnMachineFunction(MachineFunction &MF); + void getAnalysisUsage(AnalysisUsage &AU) const override; + bool runOnMachineFunction(MachineFunction &MF) override; private: /// Debug. @@ -170,7 +159,7 @@ private: /// slots to use the joint slots. void remapInstructions(DenseMap &SlotRemap); - /// The input program may contain intructions which are not inside lifetime + /// The input program may contain instructions which are not inside lifetime /// markers. This can happen due to a bug in the compiler or due to a bug in /// user code (for example, returning a reference to a local variable). /// This procedure checks all of the instructions in the function and @@ -191,6 +180,7 @@ INITIALIZE_PASS_BEGIN(StackColoring, "stack-coloring", "Merge disjoint stack slots", false, false) INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree) INITIALIZE_PASS_DEPENDENCY(SlotIndexes) +INITIALIZE_PASS_DEPENDENCY(StackProtector) INITIALIZE_PASS_END(StackColoring, "stack-coloring", "Merge disjoint stack slots", false, false) @@ -198,6 +188,7 @@ void StackColoring::getAnalysisUsage(AnalysisUsage &AU) const { AU.addRequired(); AU.addPreserved(); AU.addRequired(); + AU.addRequired(); MachineFunctionPass::getAnalysisUsage(AU); } @@ -253,18 +244,16 @@ unsigned StackColoring::collectMarkers(unsigned NumSlot) { BlockInfo.Begin.resize(NumSlot); BlockInfo.End.resize(NumSlot); - for (MachineBasicBlock::iterator BI = (*FI)->begin(), BE = (*FI)->end(); - BI != BE; ++BI) { - - if (BI->getOpcode() != TargetOpcode::LIFETIME_START && - BI->getOpcode() != TargetOpcode::LIFETIME_END) + for (MachineInstr &MI : **FI) { + if (MI.getOpcode() != TargetOpcode::LIFETIME_START && + MI.getOpcode() != TargetOpcode::LIFETIME_END) continue; - Markers.push_back(BI); + Markers.push_back(&MI); - bool IsStart = BI->getOpcode() == TargetOpcode::LIFETIME_START; - const MachineOperand &MI = BI->getOperand(0); - unsigned Slot = MI.getIndex(); + bool IsStart = MI.getOpcode() == TargetOpcode::LIFETIME_START; + const MachineOperand &MO = MI.getOperand(0); + unsigned Slot = MO.getIndex(); MarkersFound++; @@ -310,11 +299,7 @@ void StackColoring::calculateLocalLiveness() { SmallPtrSet NextBBSet; - for (SmallVectorImpl::iterator - PI = BasicBlockNumbering.begin(), PE = BasicBlockNumbering.end(); - PI != PE; ++PI) { - - const MachineBasicBlock *BB = *PI; + for (const MachineBasicBlock *BB : BasicBlockNumbering) { if (!BBSet.count(BB)) continue; // Use an iterator to avoid repeated lookups. @@ -369,18 +354,14 @@ void StackColoring::calculateLocalLiveness() { changed = true; BlockInfo.LiveIn |= LocalLiveIn; - for (MachineBasicBlock::const_pred_iterator PI = BB->pred_begin(), - PE = BB->pred_end(); PI != PE; ++PI) - NextBBSet.insert(*PI); + NextBBSet.insert(BB->pred_begin(), BB->pred_end()); } if (LocalLiveOut.test(BlockInfo.LiveOut)) { changed = true; BlockInfo.LiveOut |= LocalLiveOut; - for (MachineBasicBlock::const_succ_iterator SI = BB->succ_begin(), - SE = BB->succ_end(); SI != SE; ++SI) - NextBBSet.insert(*SI); + NextBBSet.insert(BB->succ_begin(), BB->succ_end()); } } @@ -394,18 +375,15 @@ void StackColoring::calculateLiveIntervals(unsigned NumSlots) { // For each block, find which slots are active within this block // and update the live intervals. - for (MachineFunction::iterator MBB = MF->begin(), MBBe = MF->end(); - MBB != MBBe; ++MBB) { + for (const MachineBasicBlock &MBB : *MF) { Starts.clear(); Starts.resize(NumSlots); Finishes.clear(); Finishes.resize(NumSlots); // Create the interval for the basic blocks with lifetime markers in them. - for (SmallVectorImpl::const_iterator it = Markers.begin(), - e = Markers.end(); it != e; ++it) { - const MachineInstr *MI = *it; - if (MI->getParent() != MBB) + for (const MachineInstr *MI : Markers) { + if (MI->getParent() != &MBB) continue; assert((MI->getOpcode() == TargetOpcode::LIFETIME_START || @@ -429,14 +407,14 @@ void StackColoring::calculateLiveIntervals(unsigned NumSlots) { } // Create the interval of the blocks that we previously found to be 'alive'. - BlockLifetimeInfo &MBBLiveness = BlockLiveness[MBB]; + BlockLifetimeInfo &MBBLiveness = BlockLiveness[&MBB]; for (int pos = MBBLiveness.LiveIn.find_first(); pos != -1; pos = MBBLiveness.LiveIn.find_next(pos)) { - Starts[pos] = Indexes->getMBBStartIdx(MBB); + Starts[pos] = Indexes->getMBBStartIdx(&MBB); } for (int pos = MBBLiveness.LiveOut.find_first(); pos != -1; pos = MBBLiveness.LiveOut.find_next(pos)) { - Finishes[pos] = Indexes->getMBBEndIdx(MBB); + Finishes[pos] = Indexes->getMBBEndIdx(&MBB); } for (unsigned i = 0; i < NumSlots; ++i) { @@ -450,14 +428,14 @@ void StackColoring::calculateLiveIntervals(unsigned NumSlots) { SlotIndex F = Finishes[i]; if (S < F) { // We have a single consecutive region. - Intervals[i]->addRange(LiveRange(S, F, ValNum)); + Intervals[i]->addSegment(LiveInterval::Segment(S, F, ValNum)); } else { - // We have two non consecutive regions. This happens when + // We have two non-consecutive regions. This happens when // LIFETIME_START appears after the LIFETIME_END marker. - SlotIndex NewStart = Indexes->getMBBStartIdx(MBB); - SlotIndex NewFin = Indexes->getMBBEndIdx(MBB); - Intervals[i]->addRange(LiveRange(NewStart, F, ValNum)); - Intervals[i]->addRange(LiveRange(S, NewFin, ValNum)); + SlotIndex NewStart = Indexes->getMBBStartIdx(&MBB); + SlotIndex NewFin = Indexes->getMBBEndIdx(&MBB); + Intervals[i]->addSegment(LiveInterval::Segment(NewStart, F, ValNum)); + Intervals[i]->addSegment(LiveInterval::Segment(S, NewFin, ValNum)); } } } @@ -465,8 +443,8 @@ void StackColoring::calculateLiveIntervals(unsigned NumSlots) { bool StackColoring::removeAllMarkers() { unsigned Count = 0; - for (unsigned i = 0; i < Markers.size(); ++i) { - Markers[i]->eraseFromParent(); + for (MachineInstr *MI : Markers) { + MI->eraseFromParent(); Count++; } Markers.clear(); @@ -482,64 +460,74 @@ void StackColoring::remapInstructions(DenseMap &SlotRemap) { MachineModuleInfo *MMI = &MF->getMMI(); // Remap debug information that refers to stack slots. - MachineModuleInfo::VariableDbgInfoMapTy &VMap = MMI->getVariableDbgInfo(); - for (MachineModuleInfo::VariableDbgInfoMapTy::iterator VI = VMap.begin(), - VE = VMap.end(); VI != VE; ++VI) { - const MDNode *Var = VI->first; - if (!Var) continue; - std::pair &VP = VI->second; - if (SlotRemap.count(VP.first)) { - DEBUG(dbgs()<<"Remapping debug info for ["<getName()<<"].\n"); - VP.first = SlotRemap[VP.first]; + for (auto &VI : MMI->getVariableDbgInfo()) { + if (!VI.Var) + continue; + if (SlotRemap.count(VI.Slot)) { + DEBUG(dbgs()<<"Remapping debug info for ["<getName()<<"].\n"); + VI.Slot = SlotRemap[VI.Slot]; FixedDbg++; } } // Keep a list of *allocas* which need to be remapped. DenseMap Allocas; - for (DenseMap::const_iterator it = SlotRemap.begin(), - e = SlotRemap.end(); it != e; ++it) { - const AllocaInst *From = MFI->getObjectAllocation(it->first); - const AllocaInst *To = MFI->getObjectAllocation(it->second); + for (const std::pair &SI : SlotRemap) { + const AllocaInst *From = MFI->getObjectAllocation(SI.first); + const AllocaInst *To = MFI->getObjectAllocation(SI.second); assert(To && From && "Invalid allocation object"); Allocas[From] = To; + + // AA might be used later for instruction scheduling, and we need it to be + // able to deduce the correct aliasing releationships between pointers + // derived from the alloca being remapped and the target of that remapping. + // The only safe way, without directly informing AA about the remapping + // somehow, is to directly update the IR to reflect the change being made + // here. + Instruction *Inst = const_cast(To); + if (From->getType() != To->getType()) { + BitCastInst *Cast = new BitCastInst(Inst, From->getType()); + Cast->insertAfter(Inst); + Inst = Cast; + } + + // Allow the stack protector to adjust its value map to account for the + // upcoming replacement. + SP->adjustForColoring(From, To); + + // Note that this will not replace uses in MMOs (which we'll update below), + // or anywhere else (which is why we won't delete the original + // instruction). + const_cast(From)->replaceAllUsesWith(Inst); } // Remap all instructions to the new stack slots. - MachineFunction::iterator BB, BBE; - MachineBasicBlock::iterator I, IE; - for (BB = MF->begin(), BBE = MF->end(); BB != BBE; ++BB) - for (I = BB->begin(), IE = BB->end(); I != IE; ++I) { - + for (MachineBasicBlock &BB : *MF) + for (MachineInstr &I : BB) { // Skip lifetime markers. We'll remove them soon. - if (I->getOpcode() == TargetOpcode::LIFETIME_START || - I->getOpcode() == TargetOpcode::LIFETIME_END) + if (I.getOpcode() == TargetOpcode::LIFETIME_START || + I.getOpcode() == TargetOpcode::LIFETIME_END) continue; // Update the MachineMemOperand to use the new alloca. - for (MachineInstr::mmo_iterator MM = I->memoperands_begin(), - E = I->memoperands_end(); MM != E; ++MM) { - MachineMemOperand *MMO = *MM; - + for (MachineMemOperand *MMO : I.memoperands()) { const Value *V = MMO->getValue(); if (!V) continue; - const PseudoSourceValue *PSV = dyn_cast(V); - if (PSV && PSV->isConstant(MFI)) - continue; + // FIXME: In order to enable the use of TBAA when using AA in CodeGen, + // we'll also need to update the TBAA nodes in MMOs with values + // derived from the merged allocas. When doing this, we'll need to use + // the same variant of GetUnderlyingObjects that is used by the + // instruction scheduler (that can look through ptrtoint/inttoptr + // pairs). - // Climb up and find the original alloca. - V = GetUnderlyingObject(V); - // If we did not find one, or if the one that we found is not in our - // map, then move on. - if (!V || !isa(V)) { - // Clear mem operand since we don't know for sure that it doesn't - // alias a merged alloca. - MMO->setValue(0); + // We've replaced IR-level uses of the remapped allocas, so we only + // need to replace direct uses here. + if (!isa(V)) continue; - } + const AllocaInst *AI= cast(V); if (!Allocas.count(AI)) continue; @@ -549,9 +537,7 @@ void StackColoring::remapInstructions(DenseMap &SlotRemap) { } // Update all of the machine instruction operands. - for (unsigned i = 0 ; i < I->getNumOperands(); ++i) { - MachineOperand &MO = I->getOperand(i); - + for (MachineOperand &MO : I.operands()) { if (!MO.isFI()) continue; int FromSlot = MO.getIndex(); @@ -572,12 +558,12 @@ void StackColoring::remapInstructions(DenseMap &SlotRemap) { // zone are are okay, despite the fact that we don't have a good way // for validating all of the usages of the calculation. #ifndef NDEBUG - bool TouchesMemory = I->mayLoad() || I->mayStore(); + bool TouchesMemory = I.mayLoad() || I.mayStore(); // If we *don't* protect the user from escaped allocas, don't bother // validating the instructions. - if (!I->isDebugValue() && TouchesMemory && ProtectFromEscapedAllocas) { - SlotIndex Index = Indexes->getInstructionIndex(I); - LiveInterval *Interval = Intervals[FromSlot]; + if (!I.isDebugValue() && TouchesMemory && ProtectFromEscapedAllocas) { + SlotIndex Index = Indexes->getInstructionIndex(&I); + const LiveInterval *Interval = &*Intervals[FromSlot]; assert(Interval->find(Index) != Interval->end() && "Found instruction usage outside of live range."); } @@ -596,13 +582,10 @@ void StackColoring::remapInstructions(DenseMap &SlotRemap) { } void StackColoring::removeInvalidSlotRanges() { - MachineFunction::const_iterator BB, BBE; - MachineBasicBlock::const_iterator I, IE; - for (BB = MF->begin(), BBE = MF->end(); BB != BBE; ++BB) - for (I = BB->begin(), IE = BB->end(); I != IE; ++I) { - - if (I->getOpcode() == TargetOpcode::LIFETIME_START || - I->getOpcode() == TargetOpcode::LIFETIME_END || I->isDebugValue()) + for (MachineBasicBlock &BB : *MF) + for (MachineInstr &I : BB) { + if (I.getOpcode() == TargetOpcode::LIFETIME_START || + I.getOpcode() == TargetOpcode::LIFETIME_END || I.isDebugValue()) continue; // Some intervals are suspicious! In some cases we find address @@ -611,13 +594,11 @@ void StackColoring::removeInvalidSlotRanges() { // violation, but address calculations are okay. This can happen when // GEPs are hoisted outside of the lifetime zone. // So, in here we only check instructions which can read or write memory. - if (!I->mayLoad() && !I->mayStore()) + if (!I.mayLoad() && !I.mayStore()) continue; // Check all of the machine operands. - for (unsigned i = 0 ; i < I->getNumOperands(); ++i) { - const MachineOperand &MO = I->getOperand(i); - + for (const MachineOperand &MO : I.operands()) { if (!MO.isFI()) continue; @@ -631,10 +612,10 @@ void StackColoring::removeInvalidSlotRanges() { // Check that the used slot is inside the calculated lifetime range. // If it is not, warn about it and invalidate the range. - LiveInterval *Interval = Intervals[Slot]; - SlotIndex Index = Indexes->getInstructionIndex(I); + LiveInterval *Interval = &*Intervals[Slot]; + SlotIndex Index = Indexes->getInstructionIndex(&I); if (Interval->find(Index) == Interval->end()) { - Intervals[Slot]->clear(); + Interval->clear(); DEBUG(dbgs()<<"Invalidating range #"< &SlotRemap, } bool StackColoring::runOnMachineFunction(MachineFunction &Func) { + if (skipOptnoneFunction(*Func.getFunction())) + return false; + DEBUG(dbgs() << "********** Stack Coloring **********\n" << "********** Function: " << ((const Value*)Func.getFunction())->getName() << '\n'); MF = &Func; MFI = MF->getFrameInfo(); Indexes = &getAnalysis(); + SP = &getAnalysis(); BlockLiveness.clear(); BasicBlocks.clear(); BasicBlockNumbering.clear(); @@ -704,9 +689,9 @@ bool StackColoring::runOnMachineFunction(MachineFunction &Func) { } for (unsigned i=0; i < NumSlots; ++i) { - LiveInterval *LI = new LiveInterval(i, 0); - Intervals.push_back(LI); + std::unique_ptr LI(new LiveInterval(i, 0)); LI->getNextValue(Indexes->getZeroIndex(), VNInfoAllocator); + Intervals.push_back(std::move(LI)); SortedSlots.push_back(i); } @@ -741,7 +726,13 @@ bool StackColoring::runOnMachineFunction(MachineFunction &Func) { // Sort the slots according to their size. Place unused slots at the end. // Use stable sort to guarantee deterministic code generation. std::stable_sort(SortedSlots.begin(), SortedSlots.end(), - SlotSizeSorter(MFI)); + [this](int LHS, int RHS) { + // We use -1 to denote a uninteresting slot. Place these slots at the end. + if (LHS == -1) return false; + if (RHS == -1) return true; + // Sort according to size. + return MFI->getObjectSize(LHS) > MFI->getObjectSize(RHS); + }); bool Changed = true; while (Changed) { @@ -756,14 +747,14 @@ bool StackColoring::runOnMachineFunction(MachineFunction &Func) { int FirstSlot = SortedSlots[I]; int SecondSlot = SortedSlots[J]; - LiveInterval *First = Intervals[FirstSlot]; - LiveInterval *Second = Intervals[SecondSlot]; + LiveInterval *First = &*Intervals[FirstSlot]; + LiveInterval *Second = &*Intervals[SecondSlot]; assert (!First->empty() && !Second->empty() && "Found an empty range"); // Merge disjoint slots. if (!First->overlaps(*Second)) { Changed = true; - First->MergeRangesInAsValue(*Second, First->getValNumInfo(0)); + First->MergeSegmentsInAsValue(*Second, First->getValNumInfo(0)); SlotRemap[SecondSlot] = FirstSlot; SortedSlots[J] = -1; DEBUG(dbgs()<<"Merging #"<