Fix PR198

[oota-llvm.git] / lib / VMCore / InstrTypes.cpp

diff --git a/lib/VMCore/InstrTypes.cpp b/lib/VMCore/InstrTypes.cpp
index f42d633dbb8c0b6cdc97c6e74818ecc9b1c0c30e..b10f9cc31cf3031fecc967e4a4f8851a45a25790 100644 (file)
--- a/lib/VMCore/InstrTypes.cpp
+++ b/lib/VMCore/InstrTypes.cpp
@@ -1,4 +1,11 @@
-//===-- InstrTypes.cpp - Implement Instruction subclasses --------*- C++ -*--=//
+//===-- InstrTypes.cpp - Implement Instruction subclasses -------*- C++ -*-===//
+// 
+//                     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 implements 
 //
@@ -6,51 +13,34 @@
 
 #include "llvm/iOther.h"
 #include "llvm/iPHINode.h"
-#include "llvm/BasicBlock.h"
 #include "llvm/Function.h"
 #include "llvm/SymbolTable.h"
+#include "llvm/Constant.h"
 #include "llvm/Type.h"
 #include <algorithm>  // find
+using namespace llvm;
 
 //===----------------------------------------------------------------------===//
 //                            TerminatorInst Class
 //===----------------------------------------------------------------------===//
 
-TerminatorInst::TerminatorInst(Instruction::TermOps iType) 
-  : Instruction(Type::VoidTy, iType, "") {
+TerminatorInst::TerminatorInst(Instruction::TermOps iType, Instruction *IB) 
+  : Instruction(Type::VoidTy, iType, "", IB) {
 }
 
-TerminatorInst::TerminatorInst(const Type *Ty, Instruction::TermOps iType,
-                              const std::string &Name = "")
-  : Instruction(Ty, iType, Name) {
+TerminatorInst::TerminatorInst(Instruction::TermOps iType, BasicBlock *IAE)
+  : Instruction(Type::VoidTy, iType) {
+  if (IAE) IAE->getInstList().push_back(this);
 }
 
 
-//===----------------------------------------------------------------------===//
-//                            FunctionArgument Class
-//===----------------------------------------------------------------------===//
-
-// Specialize setName to take care of symbol table majik
-void FunctionArgument::setName(const std::string &name, SymbolTable *ST) {
-  Function *P;
-  assert((ST == 0 || (!getParent() || ST == getParent()->getSymbolTable())) &&
-        "Invalid symtab argument!");
-  if ((P = getParent()) && hasName()) P->getSymbolTable()->remove(this);
-  Value::setName(name);
-  if (P && hasName()) P->getSymbolTable()->insert(this);
-}
-
 
 //===----------------------------------------------------------------------===//
 //                               PHINode Class
 //===----------------------------------------------------------------------===//
 
-PHINode::PHINode(const Type *Ty, const std::string &name) 
-  : Instruction(Ty, Instruction::PHINode, name) {
-}
-
-PHINode::PHINode(const PHINode &PN) 
-  : Instruction(PN.getType(), Instruction::PHINode) {
+PHINode::PHINode(const PHINode &PN)
+  : Instruction(PN.getType(), Instruction::PHI) {
   Operands.reserve(PN.Operands.size());
   for (unsigned i = 0; i < PN.Operands.size(); i+=2) {
     Operands.push_back(Use(PN.Operands[i], this));
@@ -58,20 +48,19 @@ PHINode::PHINode(const PHINode &PN)
   }
 }
 
-void PHINode::addIncoming(Value *D, BasicBlock *BB) {
-  assert(getType() == D->getType() &&
-         "All operands to PHI node must be the same type as the PHI node!");
-  Operands.push_back(Use(D, this));
-  Operands.push_back(Use(BB, this));
-}
-
 // removeIncomingValue - Remove an incoming value.  This is useful if a
 // predecessor basic block is deleted.
-Value *PHINode::removeIncomingValue(const BasicBlock *BB) {
-  op_iterator Idx = find(Operands.begin(), Operands.end(), (const Value*)BB);
-  assert(Idx != Operands.end() && "BB not in PHI node!");
-  --Idx;  // Back up to value prior to Basic block
-  Value *Removed = *Idx;
-  Operands.erase(Idx, Idx+2);  // Erase Value and BasicBlock
+Value *PHINode::removeIncomingValue(unsigned Idx, bool DeletePHIIfEmpty) {
+  assert(Idx*2 < Operands.size() && "BB not in PHI node!");
+  Value *Removed = Operands[Idx*2];
+  Operands.erase(Operands.begin()+Idx*2,     // Erase Value and BasicBlock
+                 Operands.begin()+Idx*2+2);
+
+  // If the PHI node is dead, because it has zero entries, nuke it now.
+  if (getNumOperands() == 0 && DeletePHIIfEmpty) {
+    // If anyone is using this PHI, make them use a dummy value instead...
+    replaceAllUsesWith(Constant::getNullValue(getType()));
+    getParent()->getInstList().erase(this);
+  }
   return Removed;
 }