[IR] Disallow loading and storing unsized types

Summary:
It isn't clear what is the operational meaning of loading or storing an
unsized types, since it cannot be lowered into something meaningful.
Since there does not seem to be any practical need for it either, make
such loads and stores illegal IR.

Reviewers: majnemer, chandlerc

Subscribers: mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D20846

llvm-svn: 271402

1 files changed, 2 insertions, 0 deletions

diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index fbf73509403..f7807d1e1b0 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -2963,6 +2963,7 @@ void Verifier::visitLoadInst(LoadInst &LI) {
   Type *ElTy = LI.getType();
   Assert(LI.getAlignment() <= Value::MaximumAlignment,
          "huge alignment values are unsupported", &LI);
+  Assert(ElTy->isSized(), "loading unsized types is not allowed", &LI);
   if (LI.isAtomic()) {
     Assert(LI.getOrdering() != AtomicOrdering::Release &&
                LI.getOrdering() != AtomicOrdering::AcquireRelease,
@@ -2991,6 +2992,7 @@ void Verifier::visitStoreInst(StoreInst &SI) {
          "Stored value type does not match pointer operand type!", &SI, ElTy);
   Assert(SI.getAlignment() <= Value::MaximumAlignment,
          "huge alignment values are unsupported", &SI);
+  Assert(ElTy->isSized(), "storing unsized types is not allowed", &SI);
   if (SI.isAtomic()) {
     Assert(SI.getOrdering() != AtomicOrdering::Acquire &&
                SI.getOrdering() != AtomicOrdering::AcquireRelease,