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[X86][Costmodel] Load/store i8 Stride=3 VF=32 interleaving costs 

For VF=16, costs are correct.
For VF=32, load cost is divergent.

The only sched models that for cpu's that support avx2
but not avx512 are: haswell, broadwell, skylake, zen1-3

For load we have:
https://godbolt.org/z/qKjevqf4W - for intels `Block RThroughput: <=14.0`; for ryzens, `Block RThroughput: <=4.5`
So pick cost of `14`.

For store we have:
https://godbolt.org/z/xTssTq319 - for intels `Block RThroughput: =13.0`; for ryzens, `Block RThroughput: <=5.5`
So pick cost of `13`.

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/D110961
This commit is contained in:
Roman Lebedev 2021-10-02 13:39:15 +03:00
parent d1460c88a6
commit 448c939839
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2 changed files with 2 additions and 2 deletions
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2
llvm/lib/Target/X86/X86TargetTransformInfo.cpp
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@ -5090,7 +5090,7 @@ InstructionCost X86TTIImpl::getInterleavedMemoryOpCostAVX2(
{3, MVT::v4i8, 3}, // (load 12i8 and) deinterleave into 3 x 4i8
{3, MVT::v8i8, 6}, // (load 24i8 and) deinterleave into 3 x 8i8
{3, MVT::v16i8, 11}, // (load 48i8 and) deinterleave into 3 x 16i8
{3, MVT::v32i8, 13}, // (load 96i8 and) deinterleave into 3 x 32i8
{3, MVT::v32i8, 14}, // (load 96i8 and) deinterleave into 3 x 32i8
{3, MVT::v8i32, 17}, // (load 24i32 and) deinterleave into 3 x 8i32

2
llvm/test/Analysis/CostModel/X86/interleaved-load-i8-stride-3.ll
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@ -30,7 +30,7 @@ target triple = "x86_64-unknown-linux-gnu"
; AVX2: LV: Found an estimated cost of 6 for VF 4 For instruction: %v0 = load i8, i8* %in0, align 1
; AVX2: LV: Found an estimated cost of 9 for VF 8 For instruction: %v0 = load i8, i8* %in0, align 1
; AVX2: LV: Found an estimated cost of 13 for VF 16 For instruction: %v0 = load i8, i8* %in0, align 1
; AVX2: LV: Found an estimated cost of 16 for VF 32 For instruction: %v0 = load i8, i8* %in0, align 1
; AVX2: LV: Found an estimated cost of 17 for VF 32 For instruction: %v0 = load i8, i8* %in0, align 1
;
; AVX512: LV: Found an estimated cost of 1 for VF 1 For instruction: %v0 = load i8, i8* %in0, align 1
; AVX512: LV: Found an estimated cost of 4 for VF 2 For instruction: %v0 = load i8, i8* %in0, align 1