Implement review feedback


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36564 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter.cpp
index f757183..eb0f2f1 100644
--- a/lib/CodeGen/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter.cpp
@@ -129,22 +129,13 @@
     O << "\n";
     for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
          I!=E; ++I) {
-      const Constant *Aliasee = dyn_cast_or_null<Constant>(I->getAliasee());
-      assert(Aliasee && "Aliasee cannot be null");
-
       std::string Name = Mang->getValueName(I);
       std::string Target;
       
-      if (const GlobalValue *GV = dyn_cast<GlobalValue>(Aliasee))
+      if (const GlobalValue *GV = I->getAliasedGlobal())
         Target = Mang->getValueName(GV);
-      else {
-        const ConstantExpr *CE = 0;
-        if ((CE = dyn_cast<ConstantExpr>(Aliasee)) &&
-            (CE->getOpcode() == Instruction::BitCast))
-          Target = Mang->getValueName(CE->getOperand(0));
-        else
-          assert(0 && "Unsupported aliasee");
-      }
+      else
+        assert(0 && "Unsupported aliasee");
       
       if (I->hasExternalLinkage())
         O << "\t.globl\t" << Name << "\n";
diff --git a/lib/Transforms/IPO/GlobalDCE.cpp b/lib/Transforms/IPO/GlobalDCE.cpp
index 9015068..56879e2 100644
--- a/lib/Transforms/IPO/GlobalDCE.cpp
+++ b/lib/Transforms/IPO/GlobalDCE.cpp
@@ -76,7 +76,7 @@
   for (Module::alias_iterator I = M.alias_begin(), E = M.alias_end();
        I != E; ++I) {
     // Aliases are always needed even if they are not used.
-    MarkUsedGlobalsAsNeeded(cast<Constant>(I->getAliasee()));
+    MarkUsedGlobalsAsNeeded(I->getAliasee());
   }
 
   // Now that all globals which are needed are in the AliveGlobals set, we loop
diff --git a/lib/VMCore/AsmWriter.cpp b/lib/VMCore/AsmWriter.cpp
index 656a7be..ac68e8d 100644
--- a/lib/VMCore/AsmWriter.cpp
+++ b/lib/VMCore/AsmWriter.cpp
@@ -926,8 +926,7 @@
    assert(0 && "Invalid alias linkage");
   }
   
-  const Constant *Aliasee = dyn_cast_or_null<Constant>(GA->getAliasee());
-  assert(Aliasee && "Aliasee cannot be null");
+  const Constant *Aliasee = GA->getAliasee();
     
   if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(Aliasee)) {
     printType(GV->getType());
diff --git a/lib/VMCore/Globals.cpp b/lib/VMCore/Globals.cpp
index 88a8c0b..aeb34f4 100644
--- a/lib/VMCore/Globals.cpp
+++ b/lib/VMCore/Globals.cpp
@@ -12,6 +12,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Constants.h"
 #include "llvm/GlobalVariable.h"
 #include "llvm/GlobalAlias.h"
 #include "llvm/DerivedTypes.h"
@@ -193,16 +194,36 @@
 }
 
 bool GlobalAlias::isDeclaration() const {
-  const GlobalValue* AV = dyn_cast_or_null<const GlobalValue>(getAliasee());
-  return (AV && AV->isDeclaration());
+  const GlobalValue* AV = getAliasedGlobal();
+  if (AV)
+    return AV->isDeclaration();
+  else
+    return false;
 }
 
 void GlobalAlias::setAliasee(Constant *Aliasee) 
 {
-  if (Aliasee) {
-    assert(Aliasee->getType() == getType() && 
+  if (Aliasee)
+    assert(Aliasee->getType() == getType() &&
            "Alias and aliasee types should match!");
-    setOperand(0, Aliasee);
-  }
+  
+  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>(Aliasee)) &&
+          (CE->getOpcode() == Instruction::BitCast))
+        return cast<GlobalValue>(CE->getOperand(0));
+      else
+        assert(0 && "Unsupported aliasee");
+    }
+  } else
+    return 0;
 }
 
diff --git a/lib/VMCore/Verifier.cpp b/lib/VMCore/Verifier.cpp
index c580e70..8e632e2 100644
--- a/lib/VMCore/Verifier.cpp
+++ b/lib/VMCore/Verifier.cpp
@@ -321,7 +321,8 @@
   
   if (!isa<GlobalValue>(GA.getAliasee())) {
     const ConstantExpr *CE = dyn_cast<ConstantExpr>(GA.getAliasee());
-    Assert1(CE && CE->getOpcode() == Instruction::BitCast,
+    Assert1(CE && CE->getOpcode() == Instruction::BitCast &&
+            isa<GlobalValue>(CE->getOperand(0)),
             "Aliasee should be either GlobalValue or bitcast of GlobalValue",
             &GA);
   }