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[AArch64] Fix SVE FADDP latency on Neoverse-N3 #167676

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Merged
merged 2 commits into from
Nov 13, 2025
Merged

[AArch64] Fix SVE FADDP latency on Neoverse-N3 #167676

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[AArch64] Fix SVE FADDP latency on Neoverse-N3
Nov 12, 2025
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4 changes: 2 additions & 2 deletions llvm/lib/Target/AArch64/AArch64SchedNeoverseN3.td
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Original file line number Diff line number Diff line change
Expand Up @@ -1926,7 +1926,6 @@ def : InstRW<[N3Write_2c_1V], (instregex "^FAB[SD]_ZPmZ_[HSD]",
// Floating point arithmetic
def : InstRW<[N3Write_2c_1V], (instregex "^F(ADD|SUB)_(ZPm[IZ]|ZZZ)_[HSD]",
"^F(ADD|SUB)_ZPZ[IZ]_[HSD]",
"^FADDP_ZPmZZ_[HSD]",
"^FNEG_ZPmZ_[HSD]",
"^FSUBR_ZPm[IZ]_[HSD]",
"^FSUBR_(ZPZI|ZPZZ)_[HSD]")>;
Expand Down Expand Up @@ -2001,7 +2000,8 @@ def : InstRW<[N3Write_10c_4V0], (instregex "^FDIVR?_(ZPmZ|ZPZZ)_S")>;
def : InstRW<[N3Write_13c_2V0], (instregex "^FDIVR?_(ZPmZ|ZPZZ)_D")>;

// Floating point arith, min/max pairwise
def : InstRW<[N3Write_3c_1V], (instregex "^F(MAX|MIN)(NM)?P_ZPmZZ_[HSD]")>;
def : InstRW<[N3Write_3c_1V], (instregex "^FADDP_ZPmZZ_[HSD]",
"^F(MAX|MIN)(NM)?P_ZPmZZ_[HSD]")>;

// Floating point min/max
def : InstRW<[N3Write_2c_1V], (instregex "^F(MAX|MIN)(NM)?_ZPm[IZ]_[HSD]",
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6 changes: 3 additions & 3 deletions llvm/test/tools/llvm-mca/AArch64/Neoverse/N3-sve-instructions.s
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Expand Up @@ -3993,9 +3993,9 @@ zip2 z31.s, z31.s, z31.s
# CHECK-NEXT: 2 4 1.00 fadda d0, p7, d0, z31.d
# CHECK-NEXT: 8 16 4.00 fadda h0, p7, h0, z31.h
# CHECK-NEXT: 4 8 2.00 fadda s0, p7, s0, z31.s
# CHECK-NEXT: 1 2 0.50 faddp z0.h, p0/m, z0.h, z1.h
# CHECK-NEXT: 1 2 0.50 faddp z29.s, p3/m, z29.s, z30.s
# CHECK-NEXT: 1 2 0.50 faddp z31.d, p7/m, z31.d, z30.d
# CHECK-NEXT: 1 3 0.50 faddp z0.h, p0/m, z0.h, z1.h
# CHECK-NEXT: 1 3 0.50 faddp z29.s, p3/m, z29.s, z30.s
# CHECK-NEXT: 1 3 0.50 faddp z31.d, p7/m, z31.d, z30.d
# CHECK-NEXT: 1 2 0.50 faddv d0, p7, z31.d
# CHECK-NEXT: 3 6 1.50 faddv h0, p7, z31.h
# CHECK-NEXT: 2 4 1.00 faddv s0, p7, z31.s
Expand Down
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