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Diffstat (limited to 'contrib/llvm/lib/Transforms/Scalar/ADCE.cpp')
-rw-r--r--contrib/llvm/lib/Transforms/Scalar/ADCE.cpp69
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(); }