[SimplifyCFG] Don't try to create metadata-valued PHIs

We can't create metadata-valued PHIs; don't try to do so when sinking.

I created a test case for this using the @llvm.type.test intrinsic, because it
takes a metadata parameter and does not have severe side effects (thus
SimplifyCFG is willing to otherwise sink it).

Previously, running the test case would crash with:

  Invalid use of metadata!
    %.sink = select i1 %flag, metadata <...>, metadata <0x4e45dc0>
  LLVM ERROR: Broken function found, compilation aborted!

llvm-svn: 280866

1 files changed, 4 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
index e5da77e6319..5785968114c 100644
--- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -1338,6 +1338,10 @@ HoistTerminator:
 // FIXME: This should be promoted to Instruction.
 static bool canReplaceOperandWithVariable(const Instruction *I,
                                           unsigned OpIdx) {
+  // We can't have a PHI with a metadata type.
+  if (I->getOperand(OpIdx)->getType()->isMetadataTy())
+    return false;
+
   // Early exit.
   if (!isa<Constant>(I->getOperand(OpIdx)))
     return true;