[DAG] Refactor some logic. No functional change.
This patch removes function 'CommuteVectorShuffle' from X86ISelLowering.cpp
and moves its logic into SelectionDAG.cpp as method 'getCommutedVectorShuffles'.
This refactoring is in preperation of an upcoming change to the DAGCombiner.
llvm-svn: 213503
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 34f5014..22379de 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -1598,6 +1598,27 @@
return SDValue(N, 0);
}
+SDValue SelectionDAG::getCommutedVectorShuffle(const ShuffleVectorSDNode &SV) {
+ MVT VT = SV.getSimpleValueType(0);
+ unsigned NumElems = VT.getVectorNumElements();
+ SmallVector<int, 8> MaskVec;
+
+ for (unsigned i = 0; i != NumElems; ++i) {
+ int Idx = SV.getMaskElt(i);
+ if (Idx >= 0) {
+ if (Idx < (int)NumElems)
+ Idx += NumElems;
+ else
+ Idx -= NumElems;
+ }
+ MaskVec.push_back(Idx);
+ }
+
+ SDValue Op0 = SV.getOperand(0);
+ SDValue Op1 = SV.getOperand(1);
+ return getVectorShuffle(VT, SDLoc(&SV), Op1, Op0, &MaskVec[0]);
+}
+
SDValue SelectionDAG::getConvertRndSat(EVT VT, SDLoc dl,
SDValue Val, SDValue DTy,
SDValue STy, SDValue Rnd, SDValue Sat,