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[X86][Costmodel] Load/store i16 Stride=6 VF=16 interleaving costs
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The only sched models that for cpu's that support avx2
but not avx512 are: haswell, broadwell, skylake, zen1-3

For this tuple, measuring becomes problematic since there's a lot of spilling going on,
but apparently all these memory ops do not affect worst-case estimate at all here.

For load we have:
https://godbolt.org/z/5qGb9odP6 - for intels `Block RThroughput: <=106.0`; for ryzens, `Block RThroughput: <=34.8`
So pick cost of `106`.

For store we have:
https://godbolt.org/z/KrWcv4Ph7 - for intels `Block RThroughput: =58.0`; for ryzens, `Block RThroughput: <=20.5`
So pick cost of `58`.

I'm directly using the shuffling asm the llc produced,
without any manual fixups that may be needed
to ensure sequential execution.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D110593
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LebedevRI committed Sep 28, 2021
1 parent 24e42f7 commit b6b7860
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2 changes: 2 additions & 0 deletions llvm/lib/Target/X86/X86TargetTransformInfo.cpp
Expand Up @@ -5094,6 +5094,7 @@ InstructionCost X86TTIImpl::getInterleavedMemoryOpCostAVX2(
{6, MVT::v2i16, 13}, // (load 12i16 and) deinterleave into 6 x 2i16
{6, MVT::v4i16, 9}, // (load 24i16 and) deinterleave into 6 x 4i16
{6, MVT::v8i16, 39}, // (load 48i16 and) deinterleave into 6 x 8i16
{6, MVT::v16i16, 106}, // (load 96i16 and) deinterleave into 6 x 16i16

{8, MVT::v8i32, 40} // (load 64i32 and) deinterleave into 8 x 8i32
};
Expand Down Expand Up @@ -5128,6 +5129,7 @@ InstructionCost X86TTIImpl::getInterleavedMemoryOpCostAVX2(
{6, MVT::v2i16, 10}, // interleave 6 x 2i16 into 12i16 (and store)
{6, MVT::v4i16, 15}, // interleave 6 x 4i16 into 24i16 (and store)
{6, MVT::v8i16, 21}, // interleave 6 x 8i16 into 48i16 (and store)
{6, MVT::v16i16, 58}, // interleave 6 x 16i16 into 96i16 (and store)
};

if (Opcode == Instruction::Load) {
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Expand Up @@ -12,7 +12,7 @@ target triple = "x86_64-unknown-linux-gnu"
; CHECK: LV: Found an estimated cost of 16 for VF 2 For instruction: %v0 = load i16, i16* %in0, align 2
; CHECK: LV: Found an estimated cost of 11 for VF 4 For instruction: %v0 = load i16, i16* %in0, align 2
; CHECK: LV: Found an estimated cost of 42 for VF 8 For instruction: %v0 = load i16, i16* %in0, align 2
; CHECK: LV: Found an estimated cost of 342 for VF 16 For instruction: %v0 = load i16, i16* %in0, align 2
; CHECK: LV: Found an estimated cost of 112 for VF 16 For instruction: %v0 = load i16, i16* %in0, align 2
; CHECK-NOT: LV: Found an estimated cost of {{[0-9]+}} for VF {{[0-9]+}} For instruction: %v0 = load i16, i16* %in0, align 2

define void @test() {
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Expand Up @@ -12,7 +12,7 @@ target triple = "x86_64-unknown-linux-gnu"
; CHECK: LV: Found an estimated cost of 13 for VF 2 For instruction: store i16 %v5, i16* %out5, align 2
; CHECK: LV: Found an estimated cost of 17 for VF 4 For instruction: store i16 %v5, i16* %out5, align 2
; CHECK: LV: Found an estimated cost of 24 for VF 8 For instruction: store i16 %v5, i16* %out5, align 2
; CHECK: LV: Found an estimated cost of 342 for VF 16 For instruction: store i16 %v5, i16* %out5, align 2
; CHECK: LV: Found an estimated cost of 64 for VF 16 For instruction: store i16 %v5, i16* %out5, align 2
; CHECK-NOT: LV: Found an estimated cost of {{[0-9]+}} for VF {{[0-9]+}} For instruction: store i16 %v5, i16* %out5, align 2

define void @test() {
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