[PATCH] D110593: [X86][Costmodel] Load/store i16 Stride=6 VF=16 interleaving costs

Roman Lebedev via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Mon Sep 27 14:39:50 PDT 2021


lebedev.ri created this revision.
lebedev.ri added a reviewer: RKSimon.
lebedev.ri added a project: LLVM.
Herald added subscribers: pengfei, hiraditya.
lebedev.ri requested review of this revision.

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.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D110593

Files:
  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


Index: llvm/test/Analysis/CostModel/X86/interleaved-store-i16-stride-6.ll
===================================================================
--- llvm/test/Analysis/CostModel/X86/interleaved-store-i16-stride-6.ll
+++ llvm/test/Analysis/CostModel/X86/interleaved-store-i16-stride-6.ll
@@ -11,7 +11,7 @@
 ; CHECK: LV: Found an estimated cost of 1 for VF 1 For instruction:   store i16 %v5, i16* %out5, align 2
 ; 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 147 for VF 8 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-NOT: LV: Found an estimated cost of {{[0-9]+}} for VF {{[0-9]+}} For instruction:   store i16 %v5, i16* %out5, align 2
 
Index: llvm/test/Analysis/CostModel/X86/interleaved-load-i16-stride-6.ll
===================================================================
--- llvm/test/Analysis/CostModel/X86/interleaved-load-i16-stride-6.ll
+++ llvm/test/Analysis/CostModel/X86/interleaved-load-i16-stride-6.ll
@@ -11,7 +11,7 @@
 ; 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 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 123 for VF 8 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-NOT: LV: Found an estimated cost of {{[0-9]+}} for VF {{[0-9]+}} For instruction:   %v0 = load i16, i16* %in0, align 2
 
Index: llvm/lib/Target/X86/X86TargetTransformInfo.cpp
===================================================================
--- llvm/lib/Target/X86/X86TargetTransformInfo.cpp
+++ llvm/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -5093,6 +5093,7 @@
 
       {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
 
       {8, MVT::v8i32, 40} // (load 64i32 and) deinterleave into 8 x 8i32
   };
@@ -5126,6 +5127,7 @@
 
       {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)
   };
 
   if (Opcode == Instruction::Load) {


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D110593.375408.patch
Type: text/x-patch
Size: 2998 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20210927/ae1b6c2e/attachment.bin>


More information about the llvm-commits mailing list