[llvm] r199678 - Allow SMUL_LOHI and UMUL_LOHI to be narrow to MUL on targets where MUL is Custom rather than Legal. Even if the target is doing some kind of expansion for MUL, it's pretty much guaranteed to be more efficent than whatever it does for SMUL_LOHI or UMUL_LOHI!

[Owen Anderson]

Author: resistor
Date: Mon Jan 20 12:41:34 2014
New Revision: 199678

URL: http://llvm.org/viewvc/llvm-project?rev=199678&view=rev
Log:
Allow SMUL_LOHI and UMUL_LOHI to be narrow to MUL on targets where MUL is Custom rather than Legal.  Even if the target is doing some kind of expansion for MUL, it's pretty much guaranteed to be more efficent than whatever it does for SMUL_LOHI or UMUL_LOHI!

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp?rev=199678&r1=199677&r2=199678&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp Mon Jan 20 12:41:34 2014
@@ -2249,7 +2249,7 @@ SDValue DAGCombiner::SimplifyNodeWithTwo
   bool HiExists = N->hasAnyUseOfValue(1);
   if (!HiExists &&
       (!LegalOperations ||
-       TLI.isOperationLegal(LoOp, N->getValueType(0)))) {
+       TLI.isOperationLegalOrCustom(LoOp, N->getValueType(0)))) {
     SDValue Res = DAG.getNode(LoOp, SDLoc(N), N->getValueType(0),
                               N->op_begin(), N->getNumOperands());
     return CombineTo(N, Res, Res);