[Verifier] Assert gc_relocate always return a pointer type

Summary: Add an assertion in verifier.cpp to make sure gc_relocate relocate a gc pointer, and its return type has the same address space with the relocated pointer.

Reviewers: reames, AndyAyers, sanjoy, pgavlin

Reviewed By: pgavlin

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9695

llvm-svn: 237605

1 files changed, 12 insertions, 2 deletions

diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index f4bc289cf26..5dae4e08ced 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -3440,8 +3440,18 @@ void Verifier::visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI) {
            "'gc parameters' section of the statepoint call",
            &CI);
 
-    // gc_relocate does not need to be the same type as the relocated pointer.
-    // It can casted to the correct type later if it's desired
+    // Relocated value must be a pointer type, but gc_relocate does not need to return the
+    // same pointer type as the relocated pointer. It can be casted to the correct type later
+    // if it's desired. However, they must have the same address space.
+    GCRelocateOperands Operands(&CI);
+    Assert(Operands.getDerivedPtr()->getType()->isPointerTy(),
+           "gc.relocate: relocated value must be a gc pointer", &CI);
+
+    // gc_relocate return type must be a pointer type, and is verified earlier in
+    // VerifyIntrinsicType().
+    Assert(cast<PointerType>(CI.getType())->getAddressSpace() ==
+           cast<PointerType>(Operands.getDerivedPtr()->getType())->getAddressSpace(),
+           "gc.relocate: relocating a pointer shouldn't change its address space", &CI);
     break;
   }
   };