6 files changed, 33 insertions, 17 deletions
diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 2d13db2c9c9..9187c6c2bec 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -1213,7 +1213,7 @@ void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
   if (GV->getName() == "llvm.used") {
     if (MAI->hasNoDeadStrip())    // No need to emit this at all.
-      EmitLLVMUsedList(GV->getInitializer());
+      EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
     return true;
   }
 
@@ -1256,11 +1256,8 @@ bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
 /// global in the specified llvm.used list for which emitUsedDirectiveFor
 /// is true, as being used with this directive.
-void AsmPrinter::EmitLLVMUsedList(const Constant *List) {
+void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
   // Should be an array of 'i8*'.
-  const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
-  if (InitList == 0) return;
-
   for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
     const GlobalValue *GV =
       dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
diff --git a/llvm/lib/CodeGen/MachineModuleInfo.cpp b/llvm/lib/CodeGen/MachineModuleInfo.cpp
index 0ea9ae0fcc8..8af9d053b12 100644
--- a/llvm/lib/CodeGen/MachineModuleInfo.cpp
+++ b/llvm/lib/CodeGen/MachineModuleInfo.cpp
@@ -326,8 +326,7 @@ void MachineModuleInfo::AnalyzeModule(const Module &M) {
   if (!GV || !GV->hasInitializer()) return;
 
   // Should be an array of 'i8*'.
-  const ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
-  if (InitList == 0) return;
+  const ConstantArray *InitList = cast<ConstantArray>(GV->getInitializer());
 
   for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
     if (const Function *F =
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 69cb5dc3817..f7aa79cca39 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -449,6 +449,29 @@ void Verifier::visitGlobalVariable(GlobalVariable &GV) {
     }
   }
 
+  if (GV.hasName() && (GV.getName() == "llvm.used")) {
+    Assert1(!GV.hasInitializer() || GV.hasAppendingLinkage(),
+            "invalid linkage for intrinsic global variable", &GV);
+    Type *GVType = GV.getType()->getElementType();
+    if (ArrayType *ATy = dyn_cast<ArrayType>(GVType)) {
+      PointerType *PTy = dyn_cast<PointerType>(ATy->getElementType());
+      Assert1(PTy, "wrong type for intrinsic global variable", &GV);
+      if (GV.hasInitializer()) {
+        Constant *Init = GV.getInitializer();
+        ConstantArray *InitArray = dyn_cast<ConstantArray>(Init);
+        Assert1(InitArray, "wrong initalizer for intrinsic global variable",
+                Init);
+        for (unsigned i = 0, e = InitArray->getNumOperands(); i != e; ++i) {
+          Value *V = Init->getOperand(i)->stripPointerCasts();
+          // stripPointerCasts strips aliases, so we only need to check for
+          // variables and functions.
+          Assert1(isa<GlobalVariable>(V) || isa<Function>(V),
+                  "invalid llvm.used member", V);
+        }
+      }
+    }
+  }
+
   visitGlobalValue(GV);
 }
 
diff --git a/llvm/lib/Transforms/IPO/ConstantMerge.cpp b/llvm/lib/Transforms/IPO/ConstantMerge.cpp
index 8336d3ad347..b63495b9685 100644
--- a/llvm/lib/Transforms/IPO/ConstantMerge.cpp
+++ b/llvm/lib/Transforms/IPO/ConstantMerge.cpp
@@ -66,9 +66,8 @@ ModulePass *llvm::createConstantMergePass() { return new ConstantMerge(); }
 static void FindUsedValues(GlobalVariable *LLVMUsed,
                            SmallPtrSet<const GlobalValue*, 8> &UsedValues) {
   if (LLVMUsed == 0) return;
-  ConstantArray *Inits = dyn_cast<ConstantArray>(LLVMUsed->getInitializer());
-  if (Inits == 0) return;
-  
+  ConstantArray *Inits = cast<ConstantArray>(LLVMUsed->getInitializer());
+
   for (unsigned i = 0, e = Inits->getNumOperands(); i != e; ++i)
     if (GlobalValue *GV = 
         dyn_cast<GlobalValue>(Inits->getOperand(i)->stripPointerCasts()))
diff --git a/llvm/lib/Transforms/IPO/StripSymbols.cpp b/llvm/lib/Transforms/IPO/StripSymbols.cpp
index 5f8681ff454..3396f7929e6 100644
--- a/llvm/lib/Transforms/IPO/StripSymbols.cpp
+++ b/llvm/lib/Transforms/IPO/StripSymbols.cpp
@@ -195,10 +195,9 @@ static void findUsedValues(GlobalVariable *LLVMUsed,
                            SmallPtrSet<const GlobalValue*, 8> &UsedValues) {
   if (LLVMUsed == 0) return;
   UsedValues.insert(LLVMUsed);
-  
-  ConstantArray *Inits = dyn_cast<ConstantArray>(LLVMUsed->getInitializer());
-  if (Inits == 0) return;
-  
+
+  ConstantArray *Inits = cast<ConstantArray>(LLVMUsed->getInitializer());
+
   for (unsigned i = 0, e = Inits->getNumOperands(); i != e; ++i)
     if (GlobalValue *GV = 
           dyn_cast<GlobalValue>(Inits->getOperand(i)->stripPointerCasts()))
diff --git a/llvm/lib/Transforms/Scalar/GlobalMerge.cpp b/llvm/lib/Transforms/Scalar/GlobalMerge.cpp
index 5d02c68a7a4..4796eb2953a 100644
--- a/llvm/lib/Transforms/Scalar/GlobalMerge.cpp
+++ b/llvm/lib/Transforms/Scalar/GlobalMerge.cpp
@@ -200,9 +200,8 @@ void GlobalMerge::collectUsedGlobalVariables(Module &M) {
   if (!GV || !GV->hasInitializer()) return;
 
   // Should be an array of 'i8*'.
-  const ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
-  if (InitList == 0) return;
- 
+  const ConstantArray *InitList = cast<ConstantArray>(GV->getInitializer());
+
   for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
     if (const GlobalVariable *G =
         dyn_cast<GlobalVariable>(InitList->getOperand(i)->stripPointerCasts()))