//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Scalar.h"
-#include "llvm/Transforms/Utils/Local.h"
-#include "llvm/Instruction.h"
-#include "llvm/Pass.h"
-#include "llvm/Support/InstIterator.h"
#include "llvm/ADT/Statistic.h"
-#include <set>
+#include "llvm/IR/InstIterator.h"
+#include "llvm/IR/Instruction.h"
+#include "llvm/Pass.h"
+#include "llvm/Analysis/TargetLibraryInfo.h"
+#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
-namespace {
- Statistic<> DIEEliminated("die", "Number of insts removed");
- Statistic<> DCEEliminated("dce", "Number of insts removed");
+#define DEBUG_TYPE "dce"
+
+STATISTIC(DIEEliminated, "Number of insts removed by DIE pass");
+STATISTIC(DCEEliminated, "Number of insts removed");
+namespace {
//===--------------------------------------------------------------------===//
// DeadInstElimination pass implementation
//
-
struct DeadInstElimination : public BasicBlockPass {
- virtual bool runOnBasicBlock(BasicBlock &BB) {
+ static char ID; // Pass identification, replacement for typeid
+ DeadInstElimination() : BasicBlockPass(ID) {
+ initializeDeadInstEliminationPass(*PassRegistry::getPassRegistry());
+ }
+ bool runOnBasicBlock(BasicBlock &BB) override {
+ if (skipOptnoneFunction(BB))
+ return false;
+ auto *TLIP = getAnalysisIfAvailable<TargetLibraryInfoWrapperPass>();
+ TargetLibraryInfo *TLI = TLIP ? &TLIP->getTLI() : nullptr;
bool Changed = false;
- for (BasicBlock::iterator DI = BB.begin(); DI != BB.end(); )
- if (dceInstruction(DI)) {
+ for (BasicBlock::iterator DI = BB.begin(); DI != BB.end(); ) {
+ Instruction *Inst = DI++;
+ if (isInstructionTriviallyDead(Inst, TLI)) {
+ Inst->eraseFromParent();
Changed = true;
++DIEEliminated;
- } else
- ++DI;
+ }
+ }
return Changed;
}
- virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+ void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesCFG();
}
};
-
- RegisterPass<DeadInstElimination> X("die", "Dead Instruction Elimination");
}
-FunctionPass *llvm::createDeadInstEliminationPass() {
+char DeadInstElimination::ID = 0;
+INITIALIZE_PASS(DeadInstElimination, "die",
+ "Dead Instruction Elimination", false, false)
+
+Pass *llvm::createDeadInstEliminationPass() {
return new DeadInstElimination();
}
-//===----------------------------------------------------------------------===//
-// DeadCodeElimination pass implementation
-//
-
namespace {
+ //===--------------------------------------------------------------------===//
+ // DeadCodeElimination pass implementation
+ //
struct DCE : public FunctionPass {
- virtual bool runOnFunction(Function &F);
+ static char ID; // Pass identification, replacement for typeid
+ DCE() : FunctionPass(ID) {
+ initializeDCEPass(*PassRegistry::getPassRegistry());
+ }
- virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+ bool runOnFunction(Function &F) override;
+
+ void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesCFG();
}
};
-
- RegisterPass<DCE> Y("dce", "Dead Code Elimination");
}
+char DCE::ID = 0;
+INITIALIZE_PASS(DCE, "dce", "Dead Code Elimination", false, false)
+
bool DCE::runOnFunction(Function &F) {
+ if (skipOptnoneFunction(F))
+ return false;
+
+ auto *TLIP = getAnalysisIfAvailable<TargetLibraryInfoWrapperPass>();
+ TargetLibraryInfo *TLI = TLIP ? &TLIP->getTLI() : nullptr;
+
// Start out with all of the instructions in the worklist...
std::vector<Instruction*> WorkList;
for (inst_iterator i = inst_begin(F), e = inst_end(F); i != e; ++i)
Instruction *I = WorkList.back();
WorkList.pop_back();
- if (isInstructionTriviallyDead(I)) { // If the instruction is dead.
+ if (isInstructionTriviallyDead(I, TLI)) { // If the instruction is dead.
// Loop over all of the values that the instruction uses, if there are
// instructions being used, add them to the worklist, because they might
// go dead after this one is removed.
I->eraseFromParent();
// Remove the instruction from the worklist if it still exists in it.
- for (std::vector<Instruction*>::iterator WI = WorkList.begin(),
- E = WorkList.end(); WI != E; ++WI)
- if (*WI == I) {
- WorkList.erase(WI);
- --E;
- --WI;
- }
+ WorkList.erase(std::remove(WorkList.begin(), WorkList.end(), I),
+ WorkList.end());
MadeChange = true;
++DCEEliminated;