[llvm] r266951 - [SelectionDAG] Teach LegalizeVectorOps to directly Expand CTTZ_ZERO_UNDEF/CTLZ_ZERO_UNDEF to CTTZ/CTLZ directly if those ops are Legal/Custom instead of deferring it to LegalizeOps.

[Craig Topper via llvm-commits]

Author: ctopper
Date: Wed Apr 20 23:43:57 2016
New Revision: 266951

URL: http://llvm.org/viewvc/llvm-project?rev=266951&view=rev
Log:
[SelectionDAG] Teach LegalizeVectorOps to directly Expand CTTZ_ZERO_UNDEF/CTLZ_ZERO_UNDEF to CTTZ/CTLZ directly if those ops are Legal/Custom instead of deferring it to LegalizeOps.

This is needed to support CTTZ/CTLZ Custom correctly since LegalizeOps would be too late to do the custom lowering.

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

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp?rev=266951&r1=266950&r2=266951&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp Wed Apr 20 23:43:57 2016
@@ -1002,10 +1002,12 @@ SDValue VectorLegalizer::ExpandFNEG(SDVa
 }
 
 SDValue VectorLegalizer::ExpandCTLZ_CTTZ_ZERO_UNDEF(SDValue Op) {
-  // If the non-ZERO_UNDEF version is supported we can let LegalizeDAG handle.
+  // If the non-ZERO_UNDEF version is supported we can use that instead.
   unsigned Opc = Op.getOpcode() == ISD::CTLZ_ZERO_UNDEF ? ISD::CTLZ : ISD::CTTZ;
-  if (TLI.isOperationLegalOrCustom(Opc, Op.getValueType()))
-    return Op;
+  if (TLI.isOperationLegalOrCustom(Opc, Op.getValueType())) {
+    SDLoc DL(Op);
+    return DAG.getNode(Opc, DL, Op.getValueType(), Op.getOperand(0));
+  }
 
   // Otherwise go ahead and unroll.
   return DAG.UnrollVectorOp(Op.getNode());