Remove a redundant assertion in MachineBasicBlock.cpp. NFC.

[oota-llvm.git] / lib / CodeGen / UnreachableBlockElim.cpp

diff --git a/lib/CodeGen/UnreachableBlockElim.cpp b/lib/CodeGen/UnreachableBlockElim.cpp
index ebf1129d55abd5f253e02944569bffdee6b99adc..8c9631e435bfeb6cd592561e95535ccc31d51abf 100644 (file)
--- a/lib/CodeGen/UnreachableBlockElim.cpp
+++ b/lib/CodeGen/UnreachableBlockElim.cpp
@@ -21,38 +21,40 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/CodeGen/Passes.h"
-#include "llvm/Constant.h"
-#include "llvm/Instructions.h"
-#include "llvm/Function.h"
-#include "llvm/Pass.h"
-#include "llvm/Type.h"
-#include "llvm/Analysis/ProfileInfo.h"
+#include "llvm/ADT/DepthFirstIterator.h"
+#include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
-#include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/MachineLoopInfo.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/Support/CFG.h"
+#include "llvm/IR/CFG.h"
+#include "llvm/IR/Constant.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Type.h"
+#include "llvm/Pass.h"
 #include "llvm/Target/TargetInstrInfo.h"
-#include "llvm/ADT/DepthFirstIterator.h"
-#include "llvm/ADT/SmallPtrSet.h"
 using namespace llvm;
 
 namespace {
   class UnreachableBlockElim : public FunctionPass {
-    virtual bool runOnFunction(Function &F);
+    bool runOnFunction(Function &F) override;
   public:
     static char ID; // Pass identification, replacement for typeid
-    UnreachableBlockElim() : FunctionPass(ID) {}
+    UnreachableBlockElim() : FunctionPass(ID) {
+      initializeUnreachableBlockElimPass(*PassRegistry::getPassRegistry());
+    }
 
-    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
-      AU.addPreserved<ProfileInfo>();
+    void getAnalysisUsage(AnalysisUsage &AU) const override {
+      AU.addPreserved<DominatorTreeWrapperPass>();
     }
   };
 }
 char UnreachableBlockElim::ID = 0;
 INITIALIZE_PASS(UnreachableBlockElim, "unreachableblockelim",
-                "Remove unreachable blocks from the CFG", false, false);
+                "Remove unreachable blocks from the CFG", false, false)
 
 FunctionPass *llvm::createUnreachableBlockEliminationPass() {
   return new UnreachableBlockElim();
@@ -62,16 +64,15 @@ bool UnreachableBlockElim::runOnFunction(Function &F) {
   SmallPtrSet<BasicBlock*, 8> Reachable;
 
   // Mark all reachable blocks.
-  for (df_ext_iterator<Function*, SmallPtrSet<BasicBlock*, 8> > I =
-       df_ext_begin(&F, Reachable), E = df_ext_end(&F, Reachable); I != E; ++I)
-    /* Mark all reachable blocks */;
+  for (BasicBlock *BB : depth_first_ext(&F, Reachable))
+    (void)BB/* Mark all reachable blocks */;
 
   // Loop over all dead blocks, remembering them and deleting all instructions
   // in them.
   std::vector<BasicBlock*> DeadBlocks;
   for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I)
-    if (!Reachable.count(I)) {
-      BasicBlock *BB = I;
+    if (!Reachable.count(&*I)) {
+      BasicBlock *BB = &*I;
       DeadBlocks.push_back(BB);
       while (PHINode *PN = dyn_cast<PHINode>(BB->begin())) {
         PN->replaceAllUsesWith(Constant::getNullValue(PN->getType()));
@@ -83,20 +84,18 @@ bool UnreachableBlockElim::runOnFunction(Function &F) {
     }
 
   // Actually remove the blocks now.
-  ProfileInfo *PI = getAnalysisIfAvailable<ProfileInfo>();
   for (unsigned i = 0, e = DeadBlocks.size(); i != e; ++i) {
-    if (PI) PI->removeBlock(DeadBlocks[i]);
     DeadBlocks[i]->eraseFromParent();
   }
 
-  return DeadBlocks.size();
+  return !DeadBlocks.empty();
 }
 
 
 namespace {
   class UnreachableMachineBlockElim : public MachineFunctionPass {
-    virtual bool runOnMachineFunction(MachineFunction &F);
-    virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+    bool runOnMachineFunction(MachineFunction &F) override;
+    void getAnalysisUsage(AnalysisUsage &AU) const override;
     MachineModuleInfo *MMI;
   public:
     static char ID; // Pass identification, replacement for typeid
@@ -106,7 +105,7 @@ namespace {
 char UnreachableMachineBlockElim::ID = 0;
 
 INITIALIZE_PASS(UnreachableMachineBlockElim, "unreachable-mbb-elimination",
-  "Remove unreachable machine basic blocks", false, false);
+  "Remove unreachable machine basic blocks", false, false)
 
 char &llvm::UnreachableMachineBlockElimID = UnreachableMachineBlockElim::ID;
 
@@ -125,16 +124,14 @@ bool UnreachableMachineBlockElim::runOnMachineFunction(MachineFunction &F) {
   MachineLoopInfo *MLI = getAnalysisIfAvailable<MachineLoopInfo>();
 
   // Mark all reachable blocks.
-  for (df_ext_iterator<MachineFunction*, SmallPtrSet<MachineBasicBlock*, 8> >
-       I = df_ext_begin(&F, Reachable), E = df_ext_end(&F, Reachable);
-       I != E; ++I)
-    /* Mark all reachable blocks */;
+  for (MachineBasicBlock *BB : depth_first_ext(&F, Reachable))
+    (void)BB/* Mark all reachable blocks */;
 
   // Loop over all dead blocks, remembering them and deleting all instructions
   // in them.
   std::vector<MachineBasicBlock*> DeadBlocks;
   for (MachineFunction::iterator I = F.begin(), E = F.end(); I != E; ++I) {
-    MachineBasicBlock *BB = I;
+    MachineBasicBlock *BB = &*I;
 
     // Test for deadness.
     if (!Reachable.count(BB)) {
@@ -170,7 +167,7 @@ bool UnreachableMachineBlockElim::runOnMachineFunction(MachineFunction &F) {
 
   // Cleanup PHI nodes.
   for (MachineFunction::iterator I = F.begin(), E = F.end(); I != E; ++I) {
-    MachineBasicBlock *BB = I;
+    MachineBasicBlock *BB = &*I;
     // Prune unneeded PHI entries.
     SmallPtrSet<MachineBasicBlock*, 8> preds(BB->pred_begin(),
                                              BB->pred_end());
@@ -192,8 +189,11 @@ bool UnreachableMachineBlockElim::runOnMachineFunction(MachineFunction &F) {
         temp->eraseFromParent();
         ModifiedPHI = true;
 
-        if (Input != Output)
-          F.getRegInfo().replaceRegWith(Output, Input);
+        if (Input != Output) {
+          MachineRegisterInfo &MRI = F.getRegInfo();
+          MRI.constrainRegClass(Input, MRI.getRegClass(Output));
+          MRI.replaceRegWith(Output, Input);
+        }
 
         continue;
       }
@@ -204,5 +204,5 @@ bool UnreachableMachineBlockElim::runOnMachineFunction(MachineFunction &F) {
 
   F.RenumberBlocks();
 
-  return (DeadBlocks.size() || ModifiedPHI);
+  return (!DeadBlocks.empty() || ModifiedPHI);
 }