Extract the load/store type verification to a separate function.

Summary:
Added isLoadableOrStorableType to PointerType.

We were doing some checks in some places, occasionally assert()ing instead
of telling the caller. With this patch, I'm putting all type checking in
the same place for load/store type instructions, and verifying the same
thing every time.

I also added a check for load/store of a function type.

Applied extracted check to Load, Store, and Cmpxcg.

I don't have exhaustive tests for all of these, but all Error() calls in
TypeCheckLoadStoreInst are being tested (in invalid.test).

Reviewers: dblaikie, rafael

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9785

llvm-svn: 237619

2 files changed, 42 insertions, 9 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index e0800916c8c..86c61bdf66b 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -401,6 +401,12 @@ static std::error_code Error(DiagnosticHandlerFunction DiagnosticHandler,
   return Error(DiagnosticHandler, EC, EC.message());
 }
 
+static std::error_code Error(DiagnosticHandlerFunction DiagnosticHandler,
+                             const Twine &Message) {
+  return Error(DiagnosticHandler,
+               make_error_code(BitcodeError::CorruptedBitcode), Message);
+}
+
 std::error_code BitcodeReader::Error(BitcodeError E, const Twine &Message) {
   return ::Error(DiagnosticHandler, make_error_code(E), Message);
 }
@@ -3290,6 +3296,20 @@ std::error_code BitcodeReader::ParseMetadataAttachment(Function &F) {
   }
 }
 
+static std::error_code TypeCheckLoadStoreInst(DiagnosticHandlerFunction DH,
+                                              Type *ValType, Type *PtrType) {
+  if (!isa<PointerType>(PtrType))
+    return Error(DH, "Load/Store operand is not a pointer type");
+  Type *ElemType = cast<PointerType>(PtrType)->getElementType();
+
+  if (ValType && ValType != ElemType)
+    return Error(DH, "Explicit load/store type does not match pointee type of "
+                     "pointer operand");
+  if (!PointerType::isLoadableOrStorableType(ElemType))
+    return Error(DH, "Cannot load/store from pointer");
+  return std::error_code();
+}
+
 /// ParseFunctionBody - Lazily parse the specified function body block.
 std::error_code BitcodeReader::ParseFunctionBody(Function *F) {
   if (Stream.EnterSubBlock(bitc::FUNCTION_BLOCK_ID))
@@ -4071,13 +4091,11 @@ std::error_code BitcodeReader::ParseFunctionBody(Function *F) {
       Type *Ty = nullptr;
       if (OpNum + 3 == Record.size())
         Ty = getTypeByID(Record[OpNum++]);
-      if (!isa<PointerType>(Op->getType()))
-        return Error("Load operand is not a pointer type");
+      if (std::error_code EC =
+              TypeCheckLoadStoreInst(DiagnosticHandler, Ty, Op->getType()))
+        return EC;
       if (!Ty)
         Ty = cast<PointerType>(Op->getType())->getElementType();
-      else if (Ty != cast<PointerType>(Op->getType())->getElementType())
-        return Error("Explicit load type does not match pointee type of "
-                     "pointer operand");
 
       unsigned Align;
       if (std::error_code EC = parseAlignmentValue(Record[OpNum], Align))
@@ -4098,6 +4116,11 @@ std::error_code BitcodeReader::ParseFunctionBody(Function *F) {
       Type *Ty = nullptr;
       if (OpNum + 5 == Record.size())
         Ty = getTypeByID(Record[OpNum++]);
+      if (std::error_code EC =
+              TypeCheckLoadStoreInst(DiagnosticHandler, Ty, Op->getType()))
+        return EC;
+      if (!Ty)
+        Ty = cast<PointerType>(Op->getType())->getElementType();
 
       AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
       if (Ordering == NotAtomic || Ordering == Release ||
@@ -4112,10 +4135,6 @@ std::error_code BitcodeReader::ParseFunctionBody(Function *F) {
         return EC;
       I = new LoadInst(Op, "", Record[OpNum+1], Align, Ordering, SynchScope);
 
-      (void)Ty;
-      assert((!Ty || Ty == I->getType()) &&
-             "Explicit type doesn't match pointee type of the first operand");
-
       InstructionList.push_back(I);
       break;
     }
@@ -4131,6 +4150,10 @@ std::error_code BitcodeReader::ParseFunctionBody(Function *F) {
                           Val)) ||
           OpNum + 2 != Record.size())
         return Error("Invalid record");
+
+      if (std::error_code EC = TypeCheckLoadStoreInst(
+              DiagnosticHandler, Val->getType(), Ptr->getType()))
+        return EC;
       unsigned Align;
       if (std::error_code EC = parseAlignmentValue(Record[OpNum], Align))
         return EC;
@@ -4152,6 +4175,9 @@ std::error_code BitcodeReader::ParseFunctionBody(Function *F) {
           OpNum + 4 != Record.size())
         return Error("Invalid record");
 
+      if (std::error_code EC = TypeCheckLoadStoreInst(
+              DiagnosticHandler, Val->getType(), Ptr->getType()))
+        return EC;
       AtomicOrdering Ordering = GetDecodedOrdering(Record[OpNum+2]);
       if (Ordering == NotAtomic || Ordering == Acquire ||
           Ordering == AcquireRelease)
@@ -4187,6 +4213,9 @@ std::error_code BitcodeReader::ParseFunctionBody(Function *F) {
         return Error("Invalid record");
       SynchronizationScope SynchScope = GetDecodedSynchScope(Record[OpNum+2]);
 
+      if (std::error_code EC = TypeCheckLoadStoreInst(
+              DiagnosticHandler, Cmp->getType(), Ptr->getType()))
+        return EC;
       AtomicOrdering FailureOrdering;
       if (Record.size() < 7)
         FailureOrdering =
diff --git a/llvm/lib/IR/Type.cpp b/llvm/lib/IR/Type.cpp
index d8baf7c9d33..1c405168ae2 100644
--- a/llvm/lib/IR/Type.cpp
+++ b/llvm/lib/IR/Type.cpp
@@ -765,3 +765,7 @@ bool PointerType::isValidElementType(Type *ElemTy) {
   return !ElemTy->isVoidTy() && !ElemTy->isLabelTy() &&
          !ElemTy->isMetadataTy();
 }
+
+bool PointerType::isLoadableOrStorableType(Type *ElemTy) {
+  return isValidElementType(ElemTy) && !ElemTy->isFunctionTy();
+}