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[RISCV] Use Predicates instead of Added Complexity to prefer QC_SELECTEQI over QC_MVEQI. NFC #148312

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Merged
topperc merged 1 commit into from
Jul 12, 2025
Merged

[RISCV] Use Predicates instead of Added Complexity to prefer QC_SELECTEQI over QC_MVEQI. NFC #148312

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2 changes: 2 additions & 0 deletions llvm/lib/Target/RISCV/RISCVFeatures.td
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Original file line number Diff line number Diff line change
Expand Up @@ -1487,6 +1487,8 @@ def HasVendorXqcics
: Predicate<"Subtarget->hasVendorXqcics()">,
AssemblerPredicate<(all_of FeatureVendorXqcics),
"'Xqcics' (Qualcomm uC Conditional Select Extension)">;
def NoVendorXqcics
: Predicate<"!Subtarget->hasVendorXqcics()">;

def FeatureVendorXqcicsr
: RISCVExperimentalExtension<0, 4, "Qualcomm uC CSR Extension">;
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12 changes: 6 additions & 6 deletions llvm/lib/Target/RISCV/RISCVInstrInfoXqci.td
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Expand Up @@ -1484,12 +1484,16 @@ def : QCIMVCCPat <SETNE, QC_MVNE>;
def : QCIMVCCPat <SETLT, QC_MVLT>;
def : QCIMVCCPat <SETULT, QC_MVLTU>;

def : QCIMVCCIPat <SETEQ, QC_MVEQI, simm5>;
def : QCIMVCCIPat <SETNE, QC_MVNEI, simm5>;
def : QCIMVCCIPat <SETLT, QC_MVLTI, simm5>;
def : QCIMVCCIPat <SETULT, QC_MVLTUI, uimm5>;
}

// Prioritize Xqcics over these patterns.
let Predicates = [HasVendorXqcicm, NoVendorXqcics, IsRV32] in {
def : QCIMVCCIPat <SETEQ, QC_MVEQI, simm5>;
def : QCIMVCCIPat <SETNE, QC_MVNEI, simm5>;
}

let Predicates = [HasVendorXqcics, IsRV32] in {
def : Pat<(select (XLenVT GPRNoX0:$rd), (XLenVT GPRNoX0:$rs2),(XLenVT GPRNoX0:$rs3)),
(QC_SELECTNEI GPRNoX0:$rd, (XLenVT 0), GPRNoX0:$rs2, GPRNoX0:$rs3)>;
Expand All @@ -1498,12 +1502,8 @@ def : Pat<(select (XLenVT GPRNoX0:$rd), (XLenVT GPRNoX0:$rs2), simm5:$simm2),
def : Pat<(select (XLenVT GPRNoX0:$rd), simm5:$simm2,(XLenVT GPRNoX0:$rs2)),
(QC_SELECTIEQI GPRNoX0:$rd, (XLenVT 0), GPRNoX0:$rs2, simm5:$simm2)>;

// Below AddedComplexity is added to prefer these conditional select instructions over
// conditional move instructions
let AddedComplexity = 1 in {
def : QCISELECTCCIPat <SETEQ, QC_SELECTEQI>;
def : QCISELECTCCIPat <SETNE, QC_SELECTNEI>;
}

def : QCISELECTICCIPat <SETEQ, QC_SELECTIEQI>;
def : QCISELECTICCIPat <SETNE, QC_SELECTINEI>;
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