Compare all 4 bytes of the header.
[oota-llvm.git] / lib / VMCore / BasicBlock.cpp
index c7f7f53e2305d17e8c9033c399c47681d150e9d5..70265c899d7e8714a95546109644673aa47fa839 100644 (file)
@@ -14,6 +14,7 @@
 #include "llvm/BasicBlock.h"
 #include "llvm/Constants.h"
 #include "llvm/Instructions.h"
+#include "llvm/IntrinsicInst.h"
 #include "llvm/LLVMContext.h"
 #include "llvm/Type.h"
 #include "llvm/ADT/STLExtras.h"
@@ -35,7 +36,7 @@ LLVMContext &BasicBlock::getContext() const {
 
 // Explicit instantiation of SymbolTableListTraits since some of the methods
 // are not in the public header file...
-template class SymbolTableListTraits<Instruction, BasicBlock>;
+template class llvm::SymbolTableListTraits<Instruction, BasicBlock>;
 
 
 BasicBlock::BasicBlock(LLVMContext &C, const Twine &Name, Function *NewParent,
@@ -136,6 +137,36 @@ Instruction* BasicBlock::getFirstNonPHI() {
   return &*i;
 }
 
+Instruction* BasicBlock::getFirstNonPHIOrDbg() {
+  BasicBlock::iterator i = begin();
+  // All valid basic blocks should have a terminator,
+  // which is not a PHINode. If we have an invalid basic
+  // block we'll get an assertion failure when dereferencing
+  // a past-the-end iterator.
+  while (isa<PHINode>(i) || isa<DbgInfoIntrinsic>(i)) ++i;
+  return &*i;
+}
+
+Instruction* BasicBlock::getFirstNonPHIOrDbgOrLifetime() {
+  // All valid basic blocks should have a terminator,
+  // which is not a PHINode. If we have an invalid basic
+  // block we'll get an assertion failure when dereferencing
+  // a past-the-end iterator.
+  BasicBlock::iterator i = begin();
+  for (;; ++i) {
+    if (isa<PHINode>(i) || isa<DbgInfoIntrinsic>(i))
+      continue;
+
+    const IntrinsicInst *II = dyn_cast<IntrinsicInst>(i);
+    if (!II)
+      break;
+    if (II->getIntrinsicID() != Intrinsic::lifetime_start &&
+        II->getIntrinsicID() != Intrinsic::lifetime_end)
+      break;
+  }
+  return &*i;
+}
+
 void BasicBlock::dropAllReferences() {
   for(iterator I = begin(), E = end(); I != E; ++I)
     I->dropAllReferences();
@@ -216,8 +247,8 @@ void BasicBlock::removePredecessor(BasicBlock *Pred,
 
       // If the PHI _HAD_ two uses, replace PHI node with its now *single* value
       if (max_idx == 2) {
-        if (PN->getOperand(0) != PN)
-          PN->replaceAllUsesWith(PN->getOperand(0));
+        if (PN->getIncomingValue(0) != PN)
+          PN->replaceAllUsesWith(PN->getIncomingValue(0));
         else
           // We are left with an infinite loop with no entries: kill the PHI.
           PN->replaceAllUsesWith(UndefValue::get(PN->getType()));
@@ -237,10 +268,11 @@ void BasicBlock::removePredecessor(BasicBlock *Pred,
       // If all incoming values to the Phi are the same, we can replace the Phi
       // with that value.
       Value* PNV = 0;
-      if (!DontDeleteUselessPHIs && (PNV = PN->hasConstantValue())) {
-        PN->replaceAllUsesWith(PNV);
-        PN->eraseFromParent();
-      }
+      if (!DontDeleteUselessPHIs && (PNV = PN->hasConstantValue()))
+        if (PNV != PN) {
+          PN->replaceAllUsesWith(PNV);
+          PN->eraseFromParent();
+        }
     }
   }
 }
@@ -296,3 +328,19 @@ BasicBlock *BasicBlock::splitBasicBlock(iterator I, const Twine &BBName) {
   return New;
 }
 
+void BasicBlock::replaceSuccessorsPhiUsesWith(BasicBlock *New) {
+  TerminatorInst *TI = getTerminator();
+  if (!TI)
+    // Cope with being called on a BasicBlock that doesn't have a terminator
+    // yet. Clang's CodeGenFunction::EmitReturnBlock() likes to do this.
+    return;
+  for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i) {
+    BasicBlock *Succ = TI->getSuccessor(i);
+    for (iterator II = Succ->begin(); PHINode *PN = dyn_cast<PHINode>(II);
+         ++II) {
+      int i;
+      while ((i = PN->getBasicBlockIndex(this)) >= 0)
+        PN->setIncomingBlock(i, New);
+    }
+  }
+}