Correctly lower memset / memcpy of undef. It should be a nop. PR6767.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100208 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 11 insertions, 7 deletions

diff --git a/include/llvm/Target/TargetLowering.h b/include/llvm/Target/TargetLowering.h
index b0534dd..f040c9d 100644
--- a/include/llvm/Target/TargetLowering.h
+++ b/include/llvm/Target/TargetLowering.h
@@ -633,15 +633,19 @@ public:
   }
 
   /// getOptimalMemOpType - Returns the target specific optimal type for load
-  /// and store operations as a result of memset, memcpy, and memmove lowering.
-  /// If DstAlign is zero that means it's safe to destination alignment can
-  /// satisfy any constraint. Similarly if SrcAlign is zero it means there isn't
-  /// a need to check it against alignment requirement, probably because the
-  /// source does not need to be loaded. It returns EVT::Other if SelectionDAG
-  /// should be responsible for determining it.
+  /// and store operations as a result of memset, memcpy, and memmove
+  /// lowering. If DstAlign is zero that means it's safe to destination
+  /// alignment can satisfy any constraint. Similarly if SrcAlign is zero it
+  /// means there isn't a need to check it against alignment requirement,
+  /// probably because the source does not need to be loaded. If
+  /// 'NonScalarIntSafe' is true, that means it's safe to return a
+  /// non-scalar-integer type, e.g. empty string source, constant, or loaded
+  /// from memory. It returns EVT::Other if SelectionDAG should be responsible
+  /// for determining it.
   virtual EVT getOptimalMemOpType(uint64_t Size,
                                   unsigned DstAlign, unsigned SrcAlign,
-                                  bool SafeToUseFP, SelectionDAG &DAG) const {
+                                  bool NonScalarIntSafe,
+                                  SelectionDAG &DAG) const {
     return MVT::Other;
   }