Skip to content

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

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
Asher8118 merged 2 commits into from
Nov 13, 2025
Merged

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

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
22ce974
[AArch64] Fix SVE FADDP latency on Neoverse-N3
Nov 12, 2025
e9e4262
Add anchor back
Nov 12, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 2 additions & 2 deletions llvm/lib/Target/AArch64/AArch64SchedNeoverseN3.td
View file
Open in desktop
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]",
Expand Down
6 changes: 3 additions & 3 deletions llvm/test/tools/llvm-mca/AArch64/Neoverse/N3-sve-instructions.s
View file
Open in desktop
Original file line number Diff line number Diff line change
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
Loading