[libcxx-commits] [llvm] [compiler-rt] [libcxx] [clang] [mlir] [clang-tools-extra] [CostModel][X86] Fix fpext conversion cost for 16 elements (PR #76278)

[via libcxx-commits]

https://github.com/HaohaiWen updated https://github.com/llvm/llvm-project/pull/76278

>From 87f3d68e82dcc752aa727f62b8b1b56b1257b343 Mon Sep 17 00:00:00 2001
From: Haohai Wen <haohai.wen at intel.com>
Date: Sat, 23 Dec 2023 13:16:02 +0800
Subject: [PATCH 1/2] [CostModel][X86] Track fpext conversion for 16 elements

---
 llvm/test/Analysis/CostModel/X86/cast.ll | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/llvm/test/Analysis/CostModel/X86/cast.ll b/llvm/test/Analysis/CostModel/X86/cast.ll
index 5a83d4e81fd38e..e0173e9df4dc3b 100644
--- a/llvm/test/Analysis/CostModel/X86/cast.ll
+++ b/llvm/test/Analysis/CostModel/X86/cast.ll
@@ -616,27 +616,31 @@ define void @fp_conv(<8 x float> %a, <16 x float>%b, <4 x float> %c) {
 ; SSE-LABEL: 'fp_conv'
 ; SSE-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %A1 = fpext <4 x float> %c to <4 x double>
 ; SSE-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %A2 = fpext <8 x float> %a to <8 x double>
-; SSE-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %A3 = fptrunc <4 x double> undef to <4 x float>
-; SSE-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %A4 = fptrunc <8 x double> undef to <8 x float>
+; SSE-NEXT:  Cost Model: Found an estimated cost of 12 for instruction: %A3 = fpext <16 x float> %b to <16 x double>
+; SSE-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %A4 = fptrunc <4 x double> undef to <4 x float>
+; SSE-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %A5 = fptrunc <8 x double> undef to <8 x float>
 ; SSE-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void
 ;
 ; AVX-LABEL: 'fp_conv'
 ; AVX-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A1 = fpext <4 x float> %c to <4 x double>
 ; AVX-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %A2 = fpext <8 x float> %a to <8 x double>
-; AVX-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A3 = fptrunc <4 x double> undef to <4 x float>
-; AVX-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %A4 = fptrunc <8 x double> undef to <8 x float>
+; AVX-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %A3 = fpext <16 x float> %b to <16 x double>
+; AVX-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A4 = fptrunc <4 x double> undef to <4 x float>
+; AVX-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %A5 = fptrunc <8 x double> undef to <8 x float>
 ; AVX-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void
 ;
 ; AVX512-LABEL: 'fp_conv'
 ; AVX512-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A1 = fpext <4 x float> %c to <4 x double>
 ; AVX512-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A2 = fpext <8 x float> %a to <8 x double>
-; AVX512-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A3 = fptrunc <4 x double> undef to <4 x float>
-; AVX512-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A4 = fptrunc <8 x double> undef to <8 x float>
+; AVX512-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %A3 = fpext <16 x float> %b to <16 x double>
+; AVX512-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A4 = fptrunc <4 x double> undef to <4 x float>
+; AVX512-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A5 = fptrunc <8 x double> undef to <8 x float>
 ; AVX512-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void
 ;
   %A1 = fpext <4 x float> %c to <4 x double>
   %A2 = fpext <8 x float> %a to <8 x double>
-  %A3 = fptrunc <4 x double> undef to <4 x float>
-  %A4 = fptrunc <8 x double> undef to <8 x float>
+  %A3 = fpext <16 x float> %b to <16 x double>
+  %A4 = fptrunc <4 x double> undef to <4 x float>
+  %A5 = fptrunc <8 x double> undef to <8 x float>
   ret void
 }

>From 90c9efc967dd02a37ebf2abf0c771011ae670dea Mon Sep 17 00:00:00 2001
From: Haohai Wen <haohai.wen at intel.com>
Date: Sat, 23 Dec 2023 13:28:10 +0800
Subject: [PATCH 2/2] [CostModel][X86] Fix fpext conversion cost for 16
 elements

The fpext conversion cost for 16 elements should be 5.
---
 llvm/lib/Target/X86/X86TargetTransformInfo.cpp | 1 +
 llvm/test/Analysis/CostModel/X86/cast.ll       | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
index 8a04987e768a12..e7b7c9666ed43c 100644
--- a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
+++ b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -2223,6 +2223,7 @@ InstructionCost X86TTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst,
   static const TypeConversionCostTblEntry AVX512FConversionTbl[] = {
     { ISD::FP_EXTEND, MVT::v8f64,   MVT::v8f32,  1 },
     { ISD::FP_EXTEND, MVT::v8f64,   MVT::v16f32, 3 },
+    { ISD::FP_EXTEND, MVT::v16f64,  MVT::v16f32, 5 }, // 2*vcvtps2pd+vextractf64x4
     { ISD::FP_ROUND,  MVT::v8f32,   MVT::v8f64,  1 },
 
     { ISD::TRUNCATE,  MVT::v2i1,    MVT::v2i8,   3 }, // sext+vpslld+vptestmd
diff --git a/llvm/test/Analysis/CostModel/X86/cast.ll b/llvm/test/Analysis/CostModel/X86/cast.ll
index e0173e9df4dc3b..790f408b00609d 100644
--- a/llvm/test/Analysis/CostModel/X86/cast.ll
+++ b/llvm/test/Analysis/CostModel/X86/cast.ll
@@ -632,7 +632,7 @@ define void @fp_conv(<8 x float> %a, <16 x float>%b, <4 x float> %c) {
 ; AVX512-LABEL: 'fp_conv'
 ; AVX512-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A1 = fpext <4 x float> %c to <4 x double>
 ; AVX512-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A2 = fpext <8 x float> %a to <8 x double>
-; AVX512-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %A3 = fpext <16 x float> %b to <16 x double>
+; AVX512-NEXT:  Cost Model: Found an estimated cost of 5 for instruction: %A3 = fpext <16 x float> %b to <16 x double>
 ; AVX512-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A4 = fptrunc <4 x double> undef to <4 x float>
 ; AVX512-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %A5 = fptrunc <8 x double> undef to <8 x float>
 ; AVX512-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void