X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTransforms%2FScalar%2FDCE.cpp;h=e8a090af40c316f1d3d09b53d00b926f67b633aa;hb=0b8c9a80f20772c3793201ab5b251d3520b9cea3;hp=a4a1104e92428ca5d877e4f9dd8d596a9a1e3932;hpb=7f8897f22e88271cfa114998a4d6088e7c8e8e11;p=oota-llvm.git

diff --git a/lib/Transforms/Scalar/DCE.cpp b/lib/Transforms/Scalar/DCE.cpp
index a4a1104e924..e8a090af40c 100644
--- a/lib/Transforms/Scalar/DCE.cpp
+++ b/lib/Transforms/Scalar/DCE.cpp
@@ -2,8 +2,8 @@
 //
 //                     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.
 //
 //===----------------------------------------------------------------------===//
 //
@@ -16,32 +16,39 @@
 //
 //===----------------------------------------------------------------------===//
 
+#define DEBUG_TYPE "dce"
 #include "llvm/Transforms/Scalar.h"
-#include "llvm/Transforms/Utils/Local.h"
-#include "llvm/Instruction.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/IR/Instruction.h"
 #include "llvm/Pass.h"
 #include "llvm/Support/InstIterator.h"
-#include "llvm/ADT/Statistic.h"
-#include <set>
+#include "llvm/Target/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");
+STATISTIC(DIEEliminated, "Number of insts removed by DIE pass");
+STATISTIC(DCEEliminated, "Number of insts removed");
 
+namespace {
   //===--------------------------------------------------------------------===//
   // DeadInstElimination pass implementation
   //
-
   struct DeadInstElimination : public BasicBlockPass {
+    static char ID; // Pass identification, replacement for typeid
+    DeadInstElimination() : BasicBlockPass(ID) {
+      initializeDeadInstEliminationPass(*PassRegistry::getPassRegistry());
+    }
     virtual bool runOnBasicBlock(BasicBlock &BB) {
+      TargetLibraryInfo *TLI = getAnalysisIfAvailable<TargetLibraryInfo>();
       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;
     }
 
@@ -49,32 +56,41 @@ namespace {
       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 {
+    static char ID; // Pass identification, replacement for typeid
+    DCE() : FunctionPass(ID) {
+      initializeDCEPass(*PassRegistry::getPassRegistry());
+    }
+
     virtual bool runOnFunction(Function &F);
 
      virtual void getAnalysisUsage(AnalysisUsage &AU) const {
       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) {
+  TargetLibraryInfo *TLI = getAnalysisIfAvailable<TargetLibraryInfo>();
+
   // 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)
@@ -89,7 +105,7 @@ bool DCE::runOnFunction(Function &F) {
     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.
@@ -102,13 +118,8 @@ bool DCE::runOnFunction(Function &F) {
       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;