diff --git a/lib/Target/Alpha/AlphaISelDAGToDAG.cpp b/lib/Target/Alpha/AlphaISelDAGToDAG.cpp index 1a442c07bce..4c49fb9d0a2 100644 --- a/lib/Target/Alpha/AlphaISelDAGToDAG.cpp +++ b/lib/Target/Alpha/AlphaISelDAGToDAG.cpp @@ -363,6 +363,39 @@ void AlphaDAGToDAGISel::Select(SDOperand &Result, SDOperand Op) { } break; + case ISD::AND: { + ConstantSDNode* SC; + ConstantSDNode* MC; + if (N->getOperand(0).getOpcode() == ISD::SRL && + (MC = dyn_cast(N->getOperand(1))) && + (SC = dyn_cast(N->getOperand(0).getOperand(1)))) + { + uint64_t sval = SC->getValue(); + uint64_t mval = MC->getValue(); + if (get_zapImm(mval)) //the result is a zap, let the autogened stuff deal + break; + // given mask X, and shift S, we want to see if there is any zap in the mask + // if we play around with the botton S bits + uint64_t dontcare = (~0ULL) >> (64 - sval); + uint64_t mask = mval << sval; + + if (get_zapImm(mask | dontcare)) + mask = mask | dontcare; + + if (get_zapImm(mask)) { + SDOperand Src; + Select(Src, N->getOperand(0).getOperand(0)); + SDOperand Z = + SDOperand(CurDAG->getTargetNode(Alpha::ZAPNOTi, MVT::i64, Src, + getI64Imm(get_zapImm(mask))), 0); + Result = SDOperand(CurDAG->getTargetNode(Alpha::SRL, MVT::i64, Z, + getI64Imm(sval)), 0); + return; + } + } + break; + } + } SelectCode(Result, Op);