================ @@ -8695,6 +8730,83 @@ SDValue SystemZTargetLowering::combineSETCC( } static bool combineCCMask(SDValue &CCReg, int &CCValid, int &CCMask) { + // CCMask for ICmp is equal to 0, 1, 2 or 3. + const auto CCMaskForICmpEQCCVal = [](unsigned CC) { + assert(CC < 4 && "CC out of range"); + return 1 << (3 - CC); + }; + // Convert CCVal to CCMask based on CCMask and update it. + const auto convertCCValToCCMask = [&](int CCVal) { + bool Invert = false; + if (CCMask == SystemZ::CCMASK_CMP_NE) + Invert = !Invert; + if (CCMask == SystemZ::CCMASK_CMP_EQ || CCMask == SystemZ::CCMASK_CMP_NE) { + CCMask = CCMaskForICmpEQCCVal(CCVal); + if (Invert) + CCMask ^= SystemZ::CCMASK_ANY; + return true; + } else if (CCMask == SystemZ::CCMASK_CMP_LT) { + // CC in range [0, CCVal). + CCMask = ((~0U << (4 - CCVal)) & SystemZ::CCMASK_ANY); + return true; + } else if (CCMask == SystemZ::CCMASK_CMP_GT) { + // CC in range (CCVal, 3]. + CCMask = (~(~0U << (3 - CCVal))) & SystemZ::CCMASK_ANY; + return true; + } + return false; + }; + // Check (SRL (IPM (CC))) and update CCReg to combine. + const auto isSRL_IPM_CCSequence = [&CCReg](SDNode *N) { + if (!N || N->getOpcode() != ISD::SRL) + return false; + auto *SRLCount = dyn_cast<ConstantSDNode>(N->getOperand(1)); + if (!SRLCount || SRLCount->getZExtValue() != SystemZ::IPM_CC) + return false; + auto *IPM = N->getOperand(0).getNode(); + if (!IPM || IPM->getOpcode() != SystemZISD::IPM) + return false; + CCReg = IPM->getOperand(0); + return true; + }; + + auto *CCNode = CCReg.getNode(); + if (!CCNode) + return false; + + // Check (SRL (IPM)) pattern and update CCReg if true. + if (isSRL_IPM_CCSequence(CCNode)) ---------------- uweigand wrote:
CCNode cannot be SRL - SRL returns a GPR, and CCNode returns a condition code. Therefore this check can never hit. https://github.com/llvm/llvm-project/pull/125970 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits