Convert
// fold (sub c1, c2) -> c1-c2
from a no-op into an actual transformation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55886 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 2d400bd..4e49847 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -1111,7 +1111,7 @@
return DAG.getConstant(0, N->getValueType(0));
// fold (sub c1, c2) -> c1-c2
if (N0C && N1C)
- return DAG.getNode(ISD::SUB, VT, N0, N1);
+ return DAG.getConstant(N0C->getAPIntValue() - N1C->getAPIntValue(), VT);
// fold (sub x, c) -> (add x, -c)
if (N1C)
return DAG.getNode(ISD::ADD, VT, N0,