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

diff --git a/lib/VMCore/Globals.cpp b/lib/VMCore/Globals.cpp
index 198948d90288ca42175cc87fbc2b8e0a7326b27f..dae22e48aea1294ed49da7c65de9f02c93ab20ac 100644 (file)
--- a/lib/VMCore/Globals.cpp
+++ b/lib/VMCore/Globals.cpp
@@ -2,8 +2,8 @@
 //
 //                     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 is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
@@ -12,7 +12,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Constants.h"
 #include "llvm/GlobalVariable.h"
+#include "llvm/GlobalAlias.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Module.h"
 #include "llvm/Support/LeakDetector.h"
@@ -44,15 +46,15 @@ static bool removeDeadUsersOfConstant(Constant *C) {
 /// that want to check to see if a global is unused, but don't want to deal
 /// with potentially dead constants hanging off of the globals.
 void GlobalValue::removeDeadConstantUsers() {
-  
   Value::use_iterator I = use_begin(), E = use_end();
   Value::use_iterator LastNonDeadUser = E;
-  for (; I != E; ++I) {
+  while (I != E) {
     if (Constant *User = dyn_cast<Constant>(*I)) {
       if (!removeDeadUsersOfConstant(User)) {
         // If the constant wasn't dead, remember that this was the last live use
         // and move on to the next constant.
         LastNonDeadUser = I;
+        ++I;
       } else {
         // If the constant was dead, then the iterator is invalidated.
         if (LastNonDeadUser == E) {
@@ -60,10 +62,12 @@ void GlobalValue::removeDeadConstantUsers() {
           if (I == E) break;
         } else {
           I = LastNonDeadUser;
+          ++I;
         }
       }
     } else {
       LastNonDeadUser = I;
+      ++I;
     }
   }
 }
@@ -74,16 +78,18 @@ void GlobalValue::destroyConstant() {
   assert(0 && "You can't GV->destroyConstant()!");
   abort();
 }
+  
 //===----------------------------------------------------------------------===//
 // GlobalVariable Implementation
 //===----------------------------------------------------------------------===//
 
 GlobalVariable::GlobalVariable(const Type *Ty, bool constant, LinkageTypes Link,
-                               Constant *InitVal,
-                               const std::string &Name, Module *ParentModule)
-  : GlobalValue(PointerType::get(Ty), Value::GlobalVariableVal,
+                               Constant *InitVal, const std::string &Name,
+                               Module *ParentModule, bool ThreadLocal, 
+                               unsigned AddressSpace)
+  : GlobalValue(PointerType::get(Ty, AddressSpace), Value::GlobalVariableVal,
                 &Initializer, InitVal != 0, Link, Name),
-    isConstantGlobal(constant) {
+    isConstantGlobal(constant), isThreadLocalSymbol(ThreadLocal) {
   if (InitVal) {
     assert(InitVal->getType() == Ty &&
            "Initializer should be the same type as the GlobalVariable!");
@@ -99,11 +105,12 @@ GlobalVariable::GlobalVariable(const Type *Ty, bool constant, LinkageTypes Link,
 }
 
 GlobalVariable::GlobalVariable(const Type *Ty, bool constant, LinkageTypes Link,
-                               Constant *InitVal,
-                               const std::string &Name, GlobalVariable *Before)
-  : GlobalValue(PointerType::get(Ty), Value::GlobalVariableVal,
+                               Constant *InitVal, const std::string &Name,
+                               GlobalVariable *Before, bool ThreadLocal,
+                               unsigned AddressSpace)
+  : GlobalValue(PointerType::get(Ty, AddressSpace), Value::GlobalVariableVal,
                 &Initializer, InitVal != 0, Link, Name), 
-    isConstantGlobal(constant) {
+    isConstantGlobal(constant), isThreadLocalSymbol(ThreadLocal) {
   if (InitVal) {
     assert(InitVal->getType() == Ty &&
            "Initializer should be the same type as the GlobalVariable!");
@@ -118,7 +125,6 @@ GlobalVariable::GlobalVariable(const Type *Ty, bool constant, LinkageTypes Link,
     Before->getParent()->getGlobalList().insert(Before, this);
 }
 
-
 void GlobalVariable::setParent(Module *parent) {
   if (getParent())
     LeakDetector::addGarbageObject(this);
@@ -154,3 +160,73 @@ void GlobalVariable::replaceUsesOfWithOnConstant(Value *From, Value *To,
   // Okay, preconditions out of the way, replace the constant initializer.
   this->setOperand(0, cast<Constant>(To));
 }
+
+//===----------------------------------------------------------------------===//
+// GlobalAlias Implementation
+//===----------------------------------------------------------------------===//
+
+GlobalAlias::GlobalAlias(const Type *Ty, LinkageTypes Link,
+                         const std::string &Name, Constant* aliasee,
+                         Module *ParentModule)
+  : GlobalValue(Ty, Value::GlobalAliasVal, &Aliasee, 1, Link, Name) {
+  LeakDetector::addGarbageObject(this);
+
+  if (aliasee)
+    assert(aliasee->getType() == Ty && "Alias and aliasee types should match!");
+  Aliasee.init(aliasee, this);
+
+  if (ParentModule)
+    ParentModule->getAliasList().push_back(this);
+}
+
+void GlobalAlias::setParent(Module *parent) {
+  if (getParent())
+    LeakDetector::addGarbageObject(this);
+  Parent = parent;
+  if (getParent())
+    LeakDetector::removeGarbageObject(this);
+}
+
+void GlobalAlias::removeFromParent() {
+  getParent()->getAliasList().remove(this);
+}
+
+void GlobalAlias::eraseFromParent() {
+  getParent()->getAliasList().erase(this);
+}
+
+bool GlobalAlias::isDeclaration() const {
+  const GlobalValue* AV = getAliasedGlobal();
+  if (AV)
+    return AV->isDeclaration();
+  else
+    return false;
+}
+
+void GlobalAlias::setAliasee(Constant *Aliasee) 
+{
+  if (Aliasee)
+    assert(Aliasee->getType() == getType() &&
+           "Alias and aliasee types should match!");
+  
+  setOperand(0, Aliasee);
+}
+
+const GlobalValue *GlobalAlias::getAliasedGlobal() const {
+  const Constant *C = getAliasee();
+  if (C) {
+    if (const GlobalValue *GV = dyn_cast<GlobalValue>(C))
+      return GV;
+    else {
+      const ConstantExpr *CE = 0;
+      if ((CE = dyn_cast<ConstantExpr>(C)) &&
+          (CE->getOpcode() == Instruction::BitCast || 
+           CE->getOpcode() == Instruction::GetElementPtr))
+        return dyn_cast<GlobalValue>(CE->getOperand(0));
+      else
+        assert(0 && "Unsupported aliasee");
+    }
+  }
+  return 0;
+}
+