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

diff --git a/lib/VMCore/Value.cpp b/lib/VMCore/Value.cpp
index 79d8e0a46205f292cf839e122648b1fb04137120..d40aaca2773b67bbaa208fa1bc06347c566c3a2a 100644 (file)
--- a/lib/VMCore/Value.cpp
+++ b/lib/VMCore/Value.cpp
@@ -1,6 +1,6 @@
 //===-- Value.cpp - Implement the Value class -----------------------------===//
 //
-// This file implements the Value class. 
+// This file implements the Value, User, and SymTabValue classes. 
 //
 //===----------------------------------------------------------------------===//
 
@@ -8,7 +8,6 @@
 #include "llvm/InstrTypes.h"
 #include "llvm/SymbolTable.h"
 #include "llvm/SymTabValue.h"
-#include "llvm/ConstantPool.h"
 #include "llvm/ConstPoolVals.h"
 #include "llvm/Type.h"
 #ifndef NDEBUG      // Only in -g mode...
@@ -20,8 +19,8 @@
 //                                Value Class
 //===----------------------------------------------------------------------===//
 
-Value::Value(const Type *ty, ValueTy vty, const string &name = "") : Name(name){
-  Ty = ty;
+Value::Value(const Type *ty, ValueTy vty, const string &name = "")
+  : Name(name), Ty(ty, this) {
   VTy = vty;
 }
 
@@ -34,6 +33,7 @@ Value::~Value() {
   // a <badref>
   //
   if (Uses.begin() != Uses.end()) {
+    cerr << "While deleting: " << this;
     for (use_const_iterator I = Uses.begin(); I != Uses.end(); ++I)
       cerr << "Use still stuck around after Def is destroyed:" << *I << endl;
   }
@@ -43,8 +43,9 @@ Value::~Value() {
 
 void Value::replaceAllUsesWith(Value *D) {
   assert(D && "Value::replaceAllUsesWith(<null>) is invalid!");
+  assert(D != this && "V->replaceAllUsesWith(V) is NOT valid!");
   while (!Uses.empty()) {
-    User *Use = Uses.front();
+    User *Use = Uses.back();
 #ifndef NDEBUG
     unsigned NumUses = Uses.size();
 #endif
@@ -58,6 +59,16 @@ void Value::replaceAllUsesWith(Value *D) {
   }
 }
 
+// refineAbstractType - This function is implemented because we use
+// potentially abstract types, and these types may be resolved to more
+// concrete types after we are constructed.  For the value class, we simply
+// change Ty to point to the right type.  :)
+//
+void Value::refineAbstractType(const DerivedType *OldTy, const Type *NewTy) {
+  assert(Ty.get() == (const Type*)OldTy &&"Can't refine anything but my type!");
+  Ty = NewTy;
+}
+
 void Value::killUse(User *i) {
   if (i == 0) return;
   use_iterator I = find(Uses.begin(), Uses.end(), i);
@@ -73,6 +84,11 @@ User *Value::use_remove(use_iterator &I) {
   return i;
 }
 
+#ifndef NDEBUG      // Only in -g mode...
+void Value::dump() const {
+  cerr << this;
+}
+#endif
 
 //===----------------------------------------------------------------------===//
 //                                 User Class
@@ -88,14 +104,13 @@ User::User(const Type *Ty, ValueTy vty, const string &name)
 void User::replaceUsesOfWith(Value *From, Value *To) {
   if (From == To) return;   // Duh what?
 
-  for (unsigned OpNum = 0; Value *D = getOperand(OpNum); ++OpNum) {   
-    if (D == From) {  // Okay, this operand is pointing to our fake def.
+  for (unsigned i = 0, E = getNumOperands(); i != E; ++i)
+    if (getOperand(i) == From) {  // Is This operand is pointing to oldval?
       // The side effects of this setOperand call include linking to
       // "To", adding "this" to the uses list of To, and
       // most importantly, removing "this" from the use list of "From".
-      setOperand(OpNum, To); // Fix it now...
+      setOperand(i, To); // Fix it now...
     }
-  }
 }
 
 
@@ -103,22 +118,13 @@ void User::replaceUsesOfWith(Value *From, Value *To) {
 //                             SymTabValue Class
 //===----------------------------------------------------------------------===//
 
-// Instantiate Templates - This ugliness is the price we have to pay
-// for having a ValueHolderImpl.h file seperate from ValueHolder.h!  :(
-//
-template class ValueHolder<ConstPoolVal, SymTabValue>;
-
-SymTabValue::SymTabValue(const Type *Ty, ValueTy dty, const string &name = "") 
-  : Value(Ty, dty, name), ConstPool(this) { 
+SymTabValue::SymTabValue(Value *p) : ValueParent(p) { 
+  assert(ValueParent && "SymTavValue without parent!?!");
   ParentSymTab = SymTab = 0;
 }
 
 
 SymTabValue::~SymTabValue() {
-  ConstPool.dropAllReferences();
-  ConstPool.delete_all();
-  ConstPool.setParent(0);
-
   delete SymTab;
 }