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[MachineCombiner][AArch64] Change mayAlias to isLoadFoldBarrier #11870

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Merged
merged 1 commit into from
Nov 20, 2025
+1 −17
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[MachineCombiner][AArch64] Change mayAlias to isLoadFoldBarrier #11870

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18 changes: 1 addition & 17 deletions llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -7492,21 +7492,6 @@ static bool getMiscPatterns(MachineInstr &Root,
return false;
}

/// Check if a given MachineInstr `MIa` may alias with any of the instructions
/// in `MemInstrs`.
static bool mayAlias(const MachineInstr &MIa,
SmallVectorImpl<const MachineInstr *> &MemInstrs,
AliasAnalysis *AA) {
for (const MachineInstr *MIb : MemInstrs) {
if (MIa.mayAlias(AA, *MIb, /*UseTBAA*/ false)) {
MIb->dump();
return true;
}
}

return false;
}

/// Check if the given instruction forms a gather load pattern that can be
/// optimized for better Memory-Level Parallelism (MLP). This function
/// identifies chains of NEON lane load instructions that load data from
Expand Down Expand Up @@ -7600,8 +7585,7 @@ static bool getGatherLanePattern(MachineInstr &Root,

// Check for potential aliasing with any of the load instructions to
// optimize.
if ((CurrInstr.mayLoadOrStore() || CurrInstr.isCall()) &&
mayAlias(CurrInstr, LoadInstrs, nullptr))
if (CurrInstr.isLoadFoldBarrier())
return false;
}

Expand Down