[CodeExtractor] Do not extract calls to eh_typeid_for (PR39545)

The lowering for a call to eh_typeid_for changes when it's moved from
one function to another.

There are several proposals for fixing this issue in llvm.org/PR39545.
Until some solution is in place, do not allow CodeExtractor to extract
calls to eh_typeid_for, as that results in serious miscompilations.

llvm-svn: 346256

1 files changed, 11 insertions, 3 deletions

diff --git a/llvm/lib/Transforms/Utils/CodeExtractor.cpp b/llvm/lib/Transforms/Utils/CodeExtractor.cpp
index 4e48910b03c..419e1db08bf 100644
--- a/llvm/lib/Transforms/Utils/CodeExtractor.cpp
+++ b/llvm/lib/Transforms/Utils/CodeExtractor.cpp
@@ -168,14 +168,22 @@ static bool isBlockValidForExtraction(const BasicBlock &BB,
       continue;
     }
 
-    if (const CallInst *CI = dyn_cast<CallInst>(I))
-      if (const Function *F = CI->getCalledFunction())
-        if (F->getIntrinsicID() == Intrinsic::vastart) {
+    if (const CallInst *CI = dyn_cast<CallInst>(I)) {
+      if (const Function *F = CI->getCalledFunction()) {
+        auto IID = F->getIntrinsicID();
+        if (IID == Intrinsic::vastart) {
           if (AllowVarArgs)
             continue;
           else
             return false;
         }
+
+        // Currently, we miscompile outlined copies of eh_typid_for. There are
+        // proposals for fixing this in llvm.org/PR39545.
+        if (IID == Intrinsic::eh_typeid_for)
+          return false;
+      }
+    }
   }
 
   return true;