Skip to content

AMDGPU: Improve cost handling of fma/fmuladd #100798

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
arsenm merged 1 commit into from
Jul 30, 2024
Merged

AMDGPU: Improve cost handling of fma/fmuladd #100798

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
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
12 changes: 9 additions & 3 deletions llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -686,7 +686,8 @@ InstructionCost GCNTTIImpl::getArithmeticInstrCost(
// instructions for an intrinsic, even if it requires nontrivial legalization.
static bool intrinsicHasPackedVectorBenefit(Intrinsic::ID ID) {
switch (ID) {
case Intrinsic::fma: // TODO: fmuladd
case Intrinsic::fma:
case Intrinsic::fmuladd:
// There's a small benefit to using vector ops in the legalized code.
case Intrinsic::round:
case Intrinsic::uadd_sat:
Expand Down Expand Up @@ -730,8 +731,13 @@ GCNTTIImpl::getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,

switch (ICA.getID()) {
case Intrinsic::fma:
InstRate = ST->hasFastFMAF32() ? getHalfRateInstrCost(CostKind)
: getQuarterRateInstrCost(CostKind);
case Intrinsic::fmuladd:
if ((SLT == MVT::f32 && ST->hasFastFMAF32()) || SLT == MVT::f16)
InstRate = getFullRateInstrCost();
else {
InstRate = ST->hasFastFMAF32() ? getHalfRateInstrCost(CostKind)
: getQuarterRateInstrCost(CostKind);
}
break;
case Intrinsic::uadd_sat:
case Intrinsic::usub_sat:
Expand Down
28 changes: 14 additions & 14 deletions llvm/test/Analysis/CostModel/AMDGPU/fma.ll
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -10,13 +10,13 @@

define void @fma_f16() {
; FAST-LABEL: 'fma_f16'
; FAST-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %f16 = call half @llvm.fma.f16(half undef, half undef, half undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %v2f16 = call <2 x half> @llvm.fma.v2f16(<2 x half> undef, <2 x half> undef, <2 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 4 for instruction: %v3f16 = call <3 x half> @llvm.fma.v3f16(<3 x half> undef, <3 x half> undef, <3 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 4 for instruction: %v4f16 = call <4 x half> @llvm.fma.v4f16(<4 x half> undef, <4 x half> undef, <4 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 8 for instruction: %v5f16 = call <5 x half> @llvm.fma.v5f16(<5 x half> undef, <5 x half> undef, <5 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 16 for instruction: %v16f16 = call <16 x half> @llvm.fma.v16f16(<16 x half> undef, <16 x half> undef, <16 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 96 for instruction: %v17f16 = call <17 x half> @llvm.fma.v17f16(<17 x half> undef, <17 x half> undef, <17 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %f16 = call half @llvm.fma.f16(half undef, half undef, half undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %v2f16 = call <2 x half> @llvm.fma.v2f16(<2 x half> undef, <2 x half> undef, <2 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %v3f16 = call <3 x half> @llvm.fma.v3f16(<3 x half> undef, <3 x half> undef, <3 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %v4f16 = call <4 x half> @llvm.fma.v4f16(<4 x half> undef, <4 x half> undef, <4 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 4 for instruction: %v5f16 = call <5 x half> @llvm.fma.v5f16(<5 x half> undef, <5 x half> undef, <5 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 8 for instruction: %v16f16 = call <16 x half> @llvm.fma.v16f16(<16 x half> undef, <16 x half> undef, <16 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 48 for instruction: %v17f16 = call <17 x half> @llvm.fma.v17f16(<17 x half> undef, <17 x half> undef, <17 x half> undef)
; FAST-NEXT: Cost Model: Found an estimated cost of 10 for instruction: ret void
;
; SLOW-LABEL: 'fma_f16'
Expand All @@ -30,13 +30,13 @@ define void @fma_f16() {
; SLOW-NEXT: Cost Model: Found an estimated cost of 10 for instruction: ret void
;
; FAST-SIZE-LABEL: 'fma_f16'
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %f16 = call half @llvm.fma.f16(half undef, half undef, half undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %v2f16 = call <2 x half> @llvm.fma.v2f16(<2 x half> undef, <2 x half> undef, <2 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 4 for instruction: %v3f16 = call <3 x half> @llvm.fma.v3f16(<3 x half> undef, <3 x half> undef, <3 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 4 for instruction: %v4f16 = call <4 x half> @llvm.fma.v4f16(<4 x half> undef, <4 x half> undef, <4 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 8 for instruction: %v5f16 = call <5 x half> @llvm.fma.v5f16(<5 x half> undef, <5 x half> undef, <5 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 16 for instruction: %v16f16 = call <16 x half> @llvm.fma.v16f16(<16 x half> undef, <16 x half> undef, <16 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 96 for instruction: %v17f16 = call <17 x half> @llvm.fma.v17f16(<17 x half> undef, <17 x half> undef, <17 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %f16 = call half @llvm.fma.f16(half undef, half undef, half undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %v2f16 = call <2 x half> @llvm.fma.v2f16(<2 x half> undef, <2 x half> undef, <2 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %v3f16 = call <3 x half> @llvm.fma.v3f16(<3 x half> undef, <3 x half> undef, <3 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %v4f16 = call <4 x half> @llvm.fma.v4f16(<4 x half> undef, <4 x half> undef, <4 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 4 for instruction: %v5f16 = call <5 x half> @llvm.fma.v5f16(<5 x half> undef, <5 x half> undef, <5 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 8 for instruction: %v16f16 = call <16 x half> @llvm.fma.v16f16(<16 x half> undef, <16 x half> undef, <16 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 48 for instruction: %v17f16 = call <17 x half> @llvm.fma.v17f16(<17 x half> undef, <17 x half> undef, <17 x half> undef)
; FAST-SIZE-NEXT: Cost Model: Found an estimated cost of 1 for instruction: ret void
;
; SLOW-SIZE-LABEL: 'fma_f16'
Expand Down
Loading