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[X86][Costmodel] Load/store i16 Stride=2 VF=4 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 load we have:
https://godbolt.org/z/1j3nf3dro - for intels `Block RThroughput: =2.0`; for ryzens, `Block RThroughput: <=1.0`
So pick cost of `2`.

For store we have:
https://godbolt.org/z/4n1zvP37j - for intels `Block RThroughput: =1.0`; for ryzens, `Block RThroughput: <=0.5`
So pick cost of `1`.

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/D110504
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LebedevRI committed Sep 27, 2021
1 parent 354ded6 commit 49e532a
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Showing 3 changed files with 4 additions and 2 deletions.
2 changes: 2 additions & 0 deletions llvm/lib/Target/X86/X86TargetTransformInfo.cpp
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Expand Up @@ -5064,6 +5064,7 @@ InstructionCost X86TTIImpl::getInterleavedMemoryOpCostAVX2(
//
static const CostTblEntry AVX2InterleavedLoadTbl[] = {
{2, MVT::v2i16, 2}, // (load 4i16 and) deinterleave into 2 x 2i16
{2, MVT::v4i16, 2}, // (load 8i16 and) deinterleave into 2 x 4i16

{2, MVT::v4i64, 6}, // (load 8i64 and) deinterleave into 2 x 4i64

Expand All @@ -5086,6 +5087,7 @@ InstructionCost X86TTIImpl::getInterleavedMemoryOpCostAVX2(

static const CostTblEntry AVX2InterleavedStoreTbl[] = {
{2, MVT::v2i16, 1}, // interleave 2 x 2i16 into 4i16 (and store)
{2, MVT::v4i16, 1}, // interleave 2 x 4i16 into 8i16 (and store)

{2, MVT::v4i64, 6}, // interleave 2 x 4i64 into 8i64 (and store)

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Expand Up @@ -10,7 +10,7 @@ target triple = "x86_64-unknown-linux-gnu"
; CHECK: LV: Checking a loop in "test"
; CHECK: LV: Found an estimated cost of 1 for VF 1 For instruction: %v0 = load i16, i16* %in0, align 2
; CHECK: LV: Found an estimated cost of 3 for VF 2 For instruction: %v0 = load i16, i16* %in0, align 2
; CHECK: LV: Found an estimated cost of 17 for VF 4 For instruction: %v0 = load i16, i16* %in0, align 2
; CHECK: LV: Found an estimated cost of 3 for VF 4 For instruction: %v0 = load i16, i16* %in0, align 2
; CHECK: LV: Found an estimated cost of 41 for VF 8 For instruction: %v0 = load i16, i16* %in0, align 2
; CHECK: LV: Found an estimated cost of 114 for VF 16 For instruction: %v0 = load i16, i16* %in0, align 2
; CHECK: LV: Found an estimated cost of 228 for VF 32 For instruction: %v0 = load i16, i16* %in0, align 2
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Original file line number Diff line number Diff line change
Expand Up @@ -10,7 +10,7 @@ target triple = "x86_64-unknown-linux-gnu"
; CHECK: LV: Checking a loop in "test"
; CHECK: LV: Found an estimated cost of 1 for VF 1 For instruction: store i16 %v1, i16* %out1, align 2
; CHECK: LV: Found an estimated cost of 2 for VF 2 For instruction: store i16 %v1, i16* %out1, align 2
; CHECK: LV: Found an estimated cost of 17 for VF 4 For instruction: store i16 %v1, i16* %out1, align 2
; CHECK: LV: Found an estimated cost of 2 for VF 4 For instruction: store i16 %v1, i16* %out1, align 2
; CHECK: LV: Found an estimated cost of 49 for VF 8 For instruction: store i16 %v1, i16* %out1, align 2
; CHECK: LV: Found an estimated cost of 114 for VF 16 For instruction: store i16 %v1, i16* %out1, align 2
; CHECK: LV: Found an estimated cost of 228 for VF 32 For instruction: store i16 %v1, i16* %out1, align 2
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