merge of use-diet branch to trunk

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

diff --git a/lib/VMCore/Globals.cpp b/lib/VMCore/Globals.cpp
index c64b719095dae422c8b6e587c0e89e5fb680dfc4..1a328d80f6874c34e738fafe128976136aa9ceef 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.
 //
 //===----------------------------------------------------------------------===//
 //
@@ -12,10 +12,12 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Constants.h"
 #include "llvm/GlobalVariable.h"
 #include "llvm/GlobalAlias.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Module.h"
+#include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/Support/LeakDetector.h"
 using namespace llvm;
 
@@ -84,16 +86,16 @@ void GlobalValue::destroyConstant() {
 
 GlobalVariable::GlobalVariable(const Type *Ty, bool constant, LinkageTypes Link,
                                Constant *InitVal, const std::string &Name,
-                               Module *ParentModule, bool ThreadLocal)
-  : GlobalValue(PointerType::get(Ty), Value::GlobalVariableVal,
-                &Initializer, InitVal != 0, Link, Name),
+                               Module *ParentModule, bool ThreadLocal, 
+                               unsigned AddressSpace)
+  : GlobalValue(PointerType::get(Ty, AddressSpace), Value::GlobalVariableVal,
+                OperandTraits<GlobalVariable>::op_begin(this),
+                InitVal != 0, Link, Name),
     isConstantGlobal(constant), isThreadLocalSymbol(ThreadLocal) {
   if (InitVal) {
     assert(InitVal->getType() == Ty &&
            "Initializer should be the same type as the GlobalVariable!");
-    Initializer.init(InitVal, this);
-  } else {
-    Initializer.init(0, this);
+    Op<0>().init(InitVal, this);
   }
 
   LeakDetector::addGarbageObject(this);
@@ -104,16 +106,16 @@ 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, bool ThreadLocal)
-  : GlobalValue(PointerType::get(Ty), Value::GlobalVariableVal,
-                &Initializer, InitVal != 0, Link, Name), 
+                               GlobalVariable *Before, bool ThreadLocal,
+                               unsigned AddressSpace)
+  : GlobalValue(PointerType::get(Ty, AddressSpace), Value::GlobalVariableVal,
+                OperandTraits<GlobalVariable>::op_begin(this),
+                InitVal != 0, Link, Name),
     isConstantGlobal(constant), isThreadLocalSymbol(ThreadLocal) {
   if (InitVal) {
     assert(InitVal->getType() == Ty &&
            "Initializer should be the same type as the GlobalVariable!");
-    Initializer.init(InitVal, this);
-  } else {
-    Initializer.init(0, this);
+    Op<0>().init(InitVal, this);
   }
   
   LeakDetector::addGarbageObject(this);
@@ -163,12 +165,15 @@ void GlobalVariable::replaceUsesOfWithOnConstant(Value *From, Value *To,
 //===----------------------------------------------------------------------===//
 
 GlobalAlias::GlobalAlias(const Type *Ty, LinkageTypes Link,
-                         const std::string &Name, const GlobalValue* aliasee,
+                         const std::string &Name, Constant* aliasee,
                          Module *ParentModule)
-  : GlobalValue(Ty, Value::GlobalAliasVal, 0, 0,
-                Link, Name), Aliasee(aliasee) {
+  : GlobalValue(Ty, Value::GlobalAliasVal, &Op<0>(), 1, Link, Name) {
   LeakDetector::addGarbageObject(this);
 
+  if (aliasee)
+    assert(aliasee->getType() == Ty && "Alias and aliasee types should match!");
+  Op<0>().init(aliasee, this);
+
   if (ParentModule)
     ParentModule->getAliasList().push_back(this);
 }
@@ -190,12 +195,52 @@ void GlobalAlias::eraseFromParent() {
 }
 
 bool GlobalAlias::isDeclaration() const {
-  return (Aliasee && Aliasee->isDeclaration());
+  const GlobalValue* AV = getAliasedGlobal();
+  if (AV)
+    return AV->isDeclaration();
+  else
+    return false;
 }
 
-void GlobalAlias::setAliasee(const GlobalValue *GV) 
+void GlobalAlias::setAliasee(Constant *Aliasee) 
 {
-  // FIXME: Some checks?
-  Aliasee = GV;
+  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;
 }
 
+const GlobalValue *GlobalAlias::resolveAliasedGlobal() const {
+  SmallPtrSet<const GlobalValue*, 3> Visited;
+
+  const GlobalValue *GV = getAliasedGlobal();
+  Visited.insert(GV);
+
+  while (const GlobalAlias *GA = dyn_cast<GlobalAlias>(GV)) {
+    GV = GA->getAliasedGlobal();
+
+    if (!Visited.insert(GV))
+      return NULL;
+  }
+
+  return GV;
+}