Total brain cramp.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48274 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 45929713369fadae7d45d938695ce646ac9a258a..5a6077a3ca14cc3fd60f6fc805755ed7b0bdba0d 100644 (file)
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -1103,7 +1103,7 @@ SDOperand DAGCombiner::visitSUB(SDNode *N) {
   
   // fold (sub x, x) -> 0
   if (N0 == N1) {
-    if (!AfterLegalize || !MVT::isVector(VT))
+    if (AfterLegalize && ISD::isBuildVectorAllZeros(N0.Val))
       // For example, zero vectors might be normalized to a particular vector
       // type to ensure they are CSE'd. Avoid issuing zero vector nodes of
       // *unexpected* type after legalization.