Don't Place Entry Safepoints Before the llvm.frameescape() Intrinsic

llvm.frameescape() intrinsic is not a real call. The intrinsic can only exist in the entry block. Inserting a gc.statepoint() before llvm.frameescape() may split the entry block, and push the intrinsic out of the entry block.

Patch by: Swaroop.Sridhar@microsoft.com
Differential Revision: http://reviews.llvm.org/D8910

llvm-svn: 235820

1 files changed, 7 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp b/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp
index 536f2a673bb..ffed810d823 100644
--- a/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp
+++ b/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp
@@ -430,6 +430,13 @@ static Instruction *findLocationForEntrySafepoint(Function &F,
         if (II->getIntrinsicID() == Intrinsic::assume) {
           continue;
         }
+        // llvm.frameescape() intrinsic is not a real call. The intrinsic can 
+        // exist only in the entry block.
+        // Inserting a statepoint before llvm.frameescape() may split the 
+        // entry block, and push the intrinsic out of the entry block.
+        if (II->getIntrinsicID() == Intrinsic::frameescape) {
+          continue;
+        }
       }
       break;
     }