diff options
Diffstat (limited to 'contrib/llvm/lib/Transforms/Scalar/ADCE.cpp')
-rw-r--r-- | contrib/llvm/lib/Transforms/Scalar/ADCE.cpp | 69 |
1 files changed, 39 insertions, 30 deletions
diff --git a/contrib/llvm/lib/Transforms/Scalar/ADCE.cpp b/contrib/llvm/lib/Transforms/Scalar/ADCE.cpp index d6fc91641588..590a52da6b19 100644 --- a/contrib/llvm/lib/Transforms/Scalar/ADCE.cpp +++ b/contrib/llvm/lib/Transforms/Scalar/ADCE.cpp @@ -1,4 +1,4 @@ -//===- DCE.cpp - Code to perform dead code elimination --------------------===// +//===- ADCE.cpp - Code to perform dead code elimination -------------------===// // // The LLVM Compiler Infrastructure // @@ -14,52 +14,33 @@ // //===----------------------------------------------------------------------===// -#include "llvm/Transforms/Scalar.h" +#include "llvm/Transforms/Scalar/ADCE.h" #include "llvm/ADT/DepthFirstIterator.h" #include "llvm/ADT/SmallPtrSet.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/Statistic.h" +#include "llvm/Analysis/GlobalsModRef.h" #include "llvm/IR/BasicBlock.h" #include "llvm/IR/CFG.h" #include "llvm/IR/InstIterator.h" #include "llvm/IR/Instructions.h" #include "llvm/IR/IntrinsicInst.h" #include "llvm/Pass.h" +#include "llvm/Transforms/Scalar.h" using namespace llvm; #define DEBUG_TYPE "adce" STATISTIC(NumRemoved, "Number of instructions removed"); -namespace { -struct ADCE : public FunctionPass { - static char ID; // Pass identification, replacement for typeid - ADCE() : FunctionPass(ID) { - initializeADCEPass(*PassRegistry::getPassRegistry()); - } - - bool runOnFunction(Function& F) override; - - void getAnalysisUsage(AnalysisUsage& AU) const override { - AU.setPreservesCFG(); - } -}; -} - -char ADCE::ID = 0; -INITIALIZE_PASS(ADCE, "adce", "Aggressive Dead Code Elimination", false, false) - -bool ADCE::runOnFunction(Function& F) { - if (skipOptnoneFunction(F)) - return false; - +static bool aggressiveDCE(Function& F) { SmallPtrSet<Instruction*, 128> Alive; SmallVector<Instruction*, 128> Worklist; // Collect the set of "root" instructions that are known live. - for (Instruction &I : inst_range(F)) { - if (isa<TerminatorInst>(I) || isa<DbgInfoIntrinsic>(I) || - isa<LandingPadInst>(I) || I.mayHaveSideEffects()) { + for (Instruction &I : instructions(F)) { + if (isa<TerminatorInst>(I) || isa<DbgInfoIntrinsic>(I) || I.isEHPad() || + I.mayHaveSideEffects()) { Alive.insert(&I); Worklist.push_back(&I); } @@ -79,7 +60,7 @@ bool ADCE::runOnFunction(Function& F) { // which have no side effects and do not influence the control flow or return // value of the function, and may therefore be deleted safely. // NOTE: We reuse the Worklist vector here for memory efficiency. - for (Instruction &I : inst_range(F)) { + for (Instruction &I : instructions(F)) { if (!Alive.count(&I)) { Worklist.push_back(&I); I.dropAllReferences(); @@ -94,6 +75,34 @@ bool ADCE::runOnFunction(Function& F) { return !Worklist.empty(); } -FunctionPass *llvm::createAggressiveDCEPass() { - return new ADCE(); +PreservedAnalyses ADCEPass::run(Function &F) { + if (aggressiveDCE(F)) + return PreservedAnalyses::none(); + return PreservedAnalyses::all(); } + +namespace { +struct ADCELegacyPass : public FunctionPass { + static char ID; // Pass identification, replacement for typeid + ADCELegacyPass() : FunctionPass(ID) { + initializeADCELegacyPassPass(*PassRegistry::getPassRegistry()); + } + + bool runOnFunction(Function& F) override { + if (skipOptnoneFunction(F)) + return false; + return aggressiveDCE(F); + } + + void getAnalysisUsage(AnalysisUsage& AU) const override { + AU.setPreservesCFG(); + AU.addPreserved<GlobalsAAWrapperPass>(); + } +}; +} + +char ADCELegacyPass::ID = 0; +INITIALIZE_PASS(ADCELegacyPass, "adce", "Aggressive Dead Code Elimination", + false, false) + +FunctionPass *llvm::createAggressiveDCEPass() { return new ADCELegacyPass(); } |