[IRCE] Add INITIALIZE_PASS_DEPENDENCY invocations.

[oota-llvm.git] / lib / Transforms / Scalar / ConstantProp.cpp

diff --git a/lib/Transforms/Scalar/ConstantProp.cpp b/lib/Transforms/Scalar/ConstantProp.cpp
index 7598afe32b318e6c47d71241c805e78ac9363de1..c974ebb9456f879c637accaab7322f7435535c3a 100644 (file)
--- a/lib/Transforms/Scalar/ConstantProp.cpp
+++ b/lib/Transforms/Scalar/ConstantProp.cpp
@@ -1,63 +1,97 @@
-//===- ConstantProp.cpp - Code to perform Simple Constant Propogation -----===//
+//===- ConstantProp.cpp - Code to perform Simple Constant Propagation -----===//
 //
-// This file implements constant propogation and merging:
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements constant propagation and merging:
 //
 // Specifically, this:
 //   * Converts instructions like "add int 1, 2" into 3
 //
 // Notice that:
 //   * This pass has a habit of making definitions be dead.  It is a good idea
-//     to to run a DIE pass sometime after running this pass.
+//     to run a DIE pass sometime after running this pass.
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Transforms/Scalar.h"
-#include "llvm/Transforms/Utils/Local.h"
-#include "llvm/ConstantHandling.h"
-#include "llvm/Instruction.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/IR/Constant.h"
+#include "llvm/IR/InstIterator.h"
+#include "llvm/IR/Instruction.h"
 #include "llvm/Pass.h"
-#include "llvm/Support/InstIterator.h"
+#include "llvm/Analysis/TargetLibraryInfo.h"
 #include <set>
+using namespace llvm;
+
+#define DEBUG_TYPE "constprop"
+
+STATISTIC(NumInstKilled, "Number of instructions killed");
 
 namespace {
-  struct ConstantPropogation : public FunctionPass {
-    const char *getPassName() const { return "Simple Constant Propogation"; }
+  struct ConstantPropagation : public FunctionPass {
+    static char ID; // Pass identification, replacement for typeid
+    ConstantPropagation() : FunctionPass(ID) {
+      initializeConstantPropagationPass(*PassRegistry::getPassRegistry());
+    }
 
-    inline bool runOnFunction(Function *F);
+    bool runOnFunction(Function &F) override;
 
-    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
-      AU.preservesCFG();
+    void getAnalysisUsage(AnalysisUsage &AU) const override {
+      AU.setPreservesCFG();
+      AU.addRequired<TargetLibraryInfoWrapperPass>();
     }
   };
 }
 
-Pass *createConstantPropogationPass() {
-  return new ConstantPropogation();
-}
+char ConstantPropagation::ID = 0;
+INITIALIZE_PASS_BEGIN(ConstantPropagation, "constprop",
+                "Simple constant propagation", false, false)
+INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
+INITIALIZE_PASS_END(ConstantPropagation, "constprop",
+                "Simple constant propagation", false, false)
 
+FunctionPass *llvm::createConstantPropagationPass() {
+  return new ConstantPropagation();
+}
 
-bool ConstantPropogation::runOnFunction(Function *F) {
+bool ConstantPropagation::runOnFunction(Function &F) {
   // Initialize the worklist to all of the instructions ready to process...
-  std::set<Instruction*> WorkList(inst_begin(F), inst_end(F));
+  std::set<Instruction*> WorkList;
+  for(inst_iterator i = inst_begin(F), e = inst_end(F); i != e; ++i) {
+      WorkList.insert(&*i);
+  }
   bool Changed = false;
+  const DataLayout &DL = F.getParent()->getDataLayout();
+  TargetLibraryInfo *TLI =
+      &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
 
   while (!WorkList.empty()) {
     Instruction *I = *WorkList.begin();
     WorkList.erase(WorkList.begin());    // Get an element from the worklist...
 
     if (!I->use_empty())                 // Don't muck with dead instructions...
-      if (Constant *C = ConstantFoldInstruction(I)) {
+      if (Constant *C = ConstantFoldInstruction(I, DL, TLI)) {
         // Add all of the users of this instruction to the worklist, they might
-        // be constant propogatable now...
-        for (Value::use_iterator UI = I->use_begin(), UE = I->use_end();
-             UI != UE; ++UI)
-          WorkList.insert(cast<Instruction>(*UI));
-        
+        // be constant propagatable now...
+        for (User *U : I->users())
+          WorkList.insert(cast<Instruction>(U));
+
         // Replace all of the uses of a variable with uses of the constant.
         I->replaceAllUsesWith(C);
-        
+
+        // Remove the dead instruction.
+        WorkList.erase(I);
+        I->eraseFromParent();
+
         // We made a change to the function...
         Changed = true;
+        ++NumInstKilled;
       }
   }
   return Changed;