[llvm] b6b7860 - [X86][Costmodel] Load/store i16 Stride=6 VF=16 interleaving costs

[Roman Lebedev via llvm-commits]

Author: Roman Lebedev
Date: 2021-09-28T19:15:08+03:00
New Revision: b6b7860954c677003a5a0b0d4071e88aa44e9081

URL: https://github.com/llvm/llvm-project/commit/b6b7860954c677003a5a0b0d4071e88aa44e9081
DIFF: https://github.com/llvm/llvm-project/commit/b6b7860954c677003a5a0b0d4071e88aa44e9081.diff

LOG: [X86][Costmodel] Load/store i16 Stride=6 VF=16 interleaving costs

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

Added: 
    

Modified: 
    llvm/lib/Target/X86/X86TargetTransformInfo.cpp
    llvm/test/Analysis/CostModel/X86/interleaved-load-i16-stride-6.ll
    llvm/test/Analysis/CostModel/X86/interleaved-store-i16-stride-6.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
index dc8cc215c107..9a040da760c0 100644
--- a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
+++ b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -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
   };
@@ -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) {

diff  --git a/llvm/test/Analysis/CostModel/X86/interleaved-load-i16-stride-6.ll b/llvm/test/Analysis/CostModel/X86/interleaved-load-i16-stride-6.ll
index 2d13e262f006..4b837ecc8fe9 100644
--- a/llvm/test/Analysis/CostModel/X86/interleaved-load-i16-stride-6.ll
+++ b/llvm/test/Analysis/CostModel/X86/interleaved-load-i16-stride-6.ll
@@ -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() {

diff  --git a/llvm/test/Analysis/CostModel/X86/interleaved-store-i16-stride-6.ll b/llvm/test/Analysis/CostModel/X86/interleaved-store-i16-stride-6.ll
index 78d4f4d50906..6bc8c8058c54 100644
--- a/llvm/test/Analysis/CostModel/X86/interleaved-store-i16-stride-6.ll
+++ b/llvm/test/Analysis/CostModel/X86/interleaved-store-i16-stride-6.ll
@@ -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() {