diff options
Diffstat (limited to 'contrib/llvm/lib/Transforms/Scalar/Sink.cpp')
-rw-r--r-- | contrib/llvm/lib/Transforms/Scalar/Sink.cpp | 54 |
1 files changed, 32 insertions, 22 deletions
diff --git a/contrib/llvm/lib/Transforms/Scalar/Sink.cpp b/contrib/llvm/lib/Transforms/Scalar/Sink.cpp index d4595bb373e6..7348c45c5d37 100644 --- a/contrib/llvm/lib/Transforms/Scalar/Sink.cpp +++ b/contrib/llvm/lib/Transforms/Scalar/Sink.cpp @@ -12,20 +12,21 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "sink" #include "llvm/Transforms/Scalar.h" #include "llvm/ADT/Statistic.h" #include "llvm/Analysis/AliasAnalysis.h" -#include "llvm/Analysis/Dominators.h" #include "llvm/Analysis/LoopInfo.h" #include "llvm/Analysis/ValueTracking.h" -#include "llvm/Assembly/Writer.h" +#include "llvm/IR/CFG.h" +#include "llvm/IR/DataLayout.h" +#include "llvm/IR/Dominators.h" #include "llvm/IR/IntrinsicInst.h" -#include "llvm/Support/CFG.h" #include "llvm/Support/Debug.h" #include "llvm/Support/raw_ostream.h" using namespace llvm; +#define DEBUG_TYPE "sink" + STATISTIC(NumSunk, "Number of instructions sunk"); STATISTIC(NumSinkIter, "Number of sinking iterations"); @@ -34,6 +35,7 @@ namespace { DominatorTree *DT; LoopInfo *LI; AliasAnalysis *AA; + const DataLayout *DL; public: static char ID; // Pass identification @@ -41,15 +43,15 @@ namespace { initializeSinkingPass(*PassRegistry::getPassRegistry()); } - virtual bool runOnFunction(Function &F); + bool runOnFunction(Function &F) override; - virtual void getAnalysisUsage(AnalysisUsage &AU) const { + void getAnalysisUsage(AnalysisUsage &AU) const override { AU.setPreservesCFG(); FunctionPass::getAnalysisUsage(AU); AU.addRequired<AliasAnalysis>(); - AU.addRequired<DominatorTree>(); + AU.addRequired<DominatorTreeWrapperPass>(); AU.addRequired<LoopInfo>(); - AU.addPreserved<DominatorTree>(); + AU.addPreserved<DominatorTreeWrapperPass>(); AU.addPreserved<LoopInfo>(); } private: @@ -63,7 +65,7 @@ namespace { char Sinking::ID = 0; INITIALIZE_PASS_BEGIN(Sinking, "sink", "Code sinking", false, false) INITIALIZE_PASS_DEPENDENCY(LoopInfo) -INITIALIZE_PASS_DEPENDENCY(DominatorTree) +INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass) INITIALIZE_AG_DEPENDENCY(AliasAnalysis) INITIALIZE_PASS_END(Sinking, "sink", "Code sinking", false, false) @@ -77,15 +79,14 @@ bool Sinking::AllUsesDominatedByBlock(Instruction *Inst, // This may leave a referencing dbg_value in the original block, before // the definition of the vreg. Dwarf generator handles this although the // user might not get the right info at runtime. - for (Value::use_iterator I = Inst->use_begin(), - E = Inst->use_end(); I != E; ++I) { + for (Use &U : Inst->uses()) { // Determine the block of the use. - Instruction *UseInst = cast<Instruction>(*I); + Instruction *UseInst = cast<Instruction>(U.getUser()); BasicBlock *UseBlock = UseInst->getParent(); if (PHINode *PN = dyn_cast<PHINode>(UseInst)) { // PHI nodes use the operand in the predecessor block, not the block with // the PHI. - unsigned Num = PHINode::getIncomingValueNumForOperand(I.getOperandNo()); + unsigned Num = PHINode::getIncomingValueNumForOperand(U.getOperandNo()); UseBlock = PN->getIncomingBlock(Num); } // Check that it dominates. @@ -96,9 +97,11 @@ bool Sinking::AllUsesDominatedByBlock(Instruction *Inst, } bool Sinking::runOnFunction(Function &F) { - DT = &getAnalysis<DominatorTree>(); + DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree(); LI = &getAnalysis<LoopInfo>(); AA = &getAnalysis<AliasAnalysis>(); + DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>(); + DL = DLP ? &DLP->getDataLayout() : nullptr; bool MadeChange, EverMadeChange = false; @@ -194,7 +197,7 @@ bool Sinking::IsAcceptableTarget(Instruction *Inst, if (SuccToSinkTo->getUniquePredecessor() != Inst->getParent()) { // We cannot sink a load across a critical edge - there may be stores in // other code paths. - if (!isSafeToSpeculativelyExecute(Inst)) + if (!isSafeToSpeculativelyExecute(Inst, DL)) return false; // We don't want to sink across a critical edge if we don't dominate the @@ -205,7 +208,7 @@ bool Sinking::IsAcceptableTarget(Instruction *Inst, // Don't sink instructions into a loop. Loop *succ = LI->getLoopFor(SuccToSinkTo); Loop *cur = LI->getLoopFor(Inst->getParent()); - if (succ != 0 && succ != cur) + if (succ != nullptr && succ != cur) return false; } @@ -218,6 +221,13 @@ bool Sinking::IsAcceptableTarget(Instruction *Inst, /// instruction out of its current block into a successor. bool Sinking::SinkInstruction(Instruction *Inst, SmallPtrSet<Instruction *, 8> &Stores) { + + // Don't sink static alloca instructions. CodeGen assumes allocas outside the + // entry block are dynamically sized stack objects. + if (AllocaInst *AI = dyn_cast<AllocaInst>(Inst)) + if (AI->isStaticAlloca()) + return false; + // Check if it's safe to move the instruction. if (!isSafeToMove(Inst, AA, Stores)) return false; @@ -232,14 +242,14 @@ bool Sinking::SinkInstruction(Instruction *Inst, // SuccToSinkTo - This is the successor to sink this instruction to, once we // decide. - BasicBlock *SuccToSinkTo = 0; + BasicBlock *SuccToSinkTo = nullptr; // Instructions can only be sunk if all their uses are in blocks // dominated by one of the successors. // Look at all the postdominators and see if we can sink it in one. DomTreeNode *DTN = DT->getNode(Inst->getParent()); for (DomTreeNode::iterator I = DTN->begin(), E = DTN->end(); - I != E && SuccToSinkTo == 0; ++I) { + I != E && SuccToSinkTo == nullptr; ++I) { BasicBlock *Candidate = (*I)->getBlock(); if ((*I)->getIDom()->getBlock() == Inst->getParent() && IsAcceptableTarget(Inst, Candidate)) @@ -249,19 +259,19 @@ bool Sinking::SinkInstruction(Instruction *Inst, // If no suitable postdominator was found, look at all the successors and // decide which one we should sink to, if any. for (succ_iterator I = succ_begin(Inst->getParent()), - E = succ_end(Inst->getParent()); I != E && SuccToSinkTo == 0; ++I) { + E = succ_end(Inst->getParent()); I != E && !SuccToSinkTo; ++I) { if (IsAcceptableTarget(Inst, *I)) SuccToSinkTo = *I; } // If we couldn't find a block to sink to, ignore this instruction. - if (SuccToSinkTo == 0) + if (!SuccToSinkTo) return false; DEBUG(dbgs() << "Sink" << *Inst << " ("; - WriteAsOperand(dbgs(), Inst->getParent(), false); + Inst->getParent()->printAsOperand(dbgs(), false); dbgs() << " -> "; - WriteAsOperand(dbgs(), SuccToSinkTo, false); + SuccToSinkTo->printAsOperand(dbgs(), false); dbgs() << ")\n"); // Move the instruction. |