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[AArch64] Tweak fixed-length loop.dependence.mask costs #175538

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Merged
MacDue merged 3 commits into from
Feb 9, 2026
Merged

[AArch64] Tweak fixed-length loop.dependence.mask costs #175538

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b0e5b94
[AArch64] Tweak fixed-length loop.dependence.mask costs
MacDue Jan 12, 2026
4827e6e
Fixups
MacDue Feb 6, 2026
4b30f0d
Fixups
MacDue Feb 6, 2026
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8 changes: 5 additions & 3 deletions llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1071,9 +1071,11 @@ AArch64TTIImpl::getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
EVT VecVT = getTLI()->getValueType(DL, RetTy);
unsigned EltSizeInBytes =
cast<ConstantInt>(ICA.getArgs()[2])->getZExtValue();
if (is_contained({1u, 2u, 4u, 8u}, EltSizeInBytes) &&
VecVT.getVectorMinNumElements() == (16 / EltSizeInBytes))
return 1;
if (!is_contained({1u, 2u, 4u, 8u}, EltSizeInBytes) ||
VecVT.getVectorMinNumElements() != (16 / EltSizeInBytes))
break;
// For fixed-vector types we need to AND the mask with a ptrue vl<N>.
return isa<FixedVectorType>(RetTy) ? 2 : 1;
}
break;
}
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16 changes: 8 additions & 8 deletions llvm/test/Analysis/CostModel/AArch64/loop_dependence_mask.ll
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Expand Up @@ -17,10 +17,10 @@ define void @loop_dependence_war_mask(ptr %a, ptr %b) {
; CHECK-EXPANDED-NEXT: Cost Model: Found an estimated cost of 0 for instruction: ret void
;
; CHECK-LABEL: 'loop_dependence_war_mask'
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res1 = call <16 x i1> @llvm.loop.dependence.war.mask.v16i1(ptr %a, ptr %b, i64 1)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res2 = call <8 x i1> @llvm.loop.dependence.war.mask.v8i1(ptr %a, ptr %b, i64 2)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res3 = call <4 x i1> @llvm.loop.dependence.war.mask.v4i1(ptr %a, ptr %b, i64 4)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res4 = call <2 x i1> @llvm.loop.dependence.war.mask.v2i1(ptr %a, ptr %b, i64 8)
; CHECK-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %res1 = call <16 x i1> @llvm.loop.dependence.war.mask.v16i1(ptr %a, ptr %b, i64 1)
; CHECK-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %res2 = call <8 x i1> @llvm.loop.dependence.war.mask.v8i1(ptr %a, ptr %b, i64 2)
; CHECK-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %res3 = call <4 x i1> @llvm.loop.dependence.war.mask.v4i1(ptr %a, ptr %b, i64 4)
; CHECK-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %res4 = call <2 x i1> @llvm.loop.dependence.war.mask.v2i1(ptr %a, ptr %b, i64 8)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res5 = call <vscale x 16 x i1> @llvm.loop.dependence.war.mask.nxv16i1(ptr %a, ptr %b, i64 1)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res6 = call <vscale x 8 x i1> @llvm.loop.dependence.war.mask.nxv8i1(ptr %a, ptr %b, i64 2)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res7 = call <vscale x 4 x i1> @llvm.loop.dependence.war.mask.nxv4i1(ptr %a, ptr %b, i64 4)
Expand Down Expand Up @@ -54,10 +54,10 @@ define void @loop_dependence_raw_mask(ptr %a, ptr %b) {
; CHECK-EXPANDED-NEXT: Cost Model: Found an estimated cost of 0 for instruction: ret void
;
; CHECK-LABEL: 'loop_dependence_raw_mask'
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res1 = call <16 x i1> @llvm.loop.dependence.raw.mask.v16i1(ptr %a, ptr %b, i64 1)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res2 = call <8 x i1> @llvm.loop.dependence.raw.mask.v8i1(ptr %a, ptr %b, i64 2)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res3 = call <4 x i1> @llvm.loop.dependence.raw.mask.v4i1(ptr %a, ptr %b, i64 4)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res4 = call <2 x i1> @llvm.loop.dependence.raw.mask.v2i1(ptr %a, ptr %b, i64 8)
; CHECK-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %res1 = call <16 x i1> @llvm.loop.dependence.raw.mask.v16i1(ptr %a, ptr %b, i64 1)
; CHECK-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %res2 = call <8 x i1> @llvm.loop.dependence.raw.mask.v8i1(ptr %a, ptr %b, i64 2)
; CHECK-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %res3 = call <4 x i1> @llvm.loop.dependence.raw.mask.v4i1(ptr %a, ptr %b, i64 4)
; CHECK-NEXT: Cost Model: Found an estimated cost of 2 for instruction: %res4 = call <2 x i1> @llvm.loop.dependence.raw.mask.v2i1(ptr %a, ptr %b, i64 8)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res5 = call <vscale x 16 x i1> @llvm.loop.dependence.raw.mask.nxv16i1(ptr %a, ptr %b, i64 1)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res6 = call <vscale x 8 x i1> @llvm.loop.dependence.raw.mask.nxv8i1(ptr %a, ptr %b, i64 2)
; CHECK-NEXT: Cost Model: Found an estimated cost of 1 for instruction: %res7 = call <vscale x 4 x i1> @llvm.loop.dependence.raw.mask.nxv4i1(ptr %a, ptr %b, i64 4)
Expand Down