[CostModel][X86] Fix AVX2 v16i16 shift 'splat' costs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291366 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86TargetTransformInfo.cpp b/lib/Target/X86/X86TargetTransformInfo.cpp
index 829b47b..30b2055 100644 (file)
--- a/lib/Target/X86/X86TargetTransformInfo.cpp
+++ b/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -291,6 +291,20 @@ int X86TTIImpl::getArithmeticInstrCost(
       return LT.first * Entry->Cost;
   }
 
+  static const CostTblEntry AVX2UniformCostTable[] = {
+    // Uniform splats are cheaper for the following instructions.
+    { ISD::SRL,  MVT::v16i16, 1 }, // psrlw.
+    { ISD::SRA,  MVT::v16i16, 1 }, // psraw.
+  };
+
+  if (ST->hasAVX2() &&
+      ((Op2Info == TargetTransformInfo::OK_UniformConstantValue) ||
+       (Op2Info == TargetTransformInfo::OK_UniformValue))) {
+    if (const auto *Entry =
+            CostTableLookup(AVX2UniformCostTable, ISD, LT.second))
+      return LT.first * Entry->Cost;
+  }
+
   static const CostTblEntry XOPShiftCostTable[] = {
     // 128bit shifts take 1cy, but right shifts require negation beforehand.
     { ISD::SHL,     MVT::v16i8,    1 },
@@ -325,8 +339,7 @@ int X86TTIImpl::getArithmeticInstrCost(
     if (const auto *Entry = CostTableLookup(XOPShiftCostTable, ISD, LT.second))
       return LT.first * Entry->Cost;
 
-  static const CostTblEntry
-  SSE2UniformCostTable[] = {
+  static const CostTblEntry SSE2UniformCostTable[] = {
     // Uniform splats are cheaper for the following instructions.
     { ISD::SHL,  MVT::v16i8,  1 }, // psllw.
     { ISD::SHL,  MVT::v32i8,  2 }, // psllw.

diff --git a/test/Analysis/CostModel/X86/vshift-ashr-cost.ll b/test/Analysis/CostModel/X86/vshift-ashr-cost.ll
index ab1eb73..e75b5dc 100644 (file)
--- a/test/Analysis/CostModel/X86/vshift-ashr-cost.ll
+++ b/test/Analysis/CostModel/X86/vshift-ashr-cost.ll
@@ -578,9 +578,10 @@ define <16 x i16> @splatconstant_shift_v16i16(<16 x i16> %a) {
 ; SSE2: Found an estimated cost of 2 for instruction:   %shift
 ; SSE41: Found an estimated cost of 2 for instruction:   %shift
 ; AVX: Found an estimated cost of 2 for instruction:   %shift
-; AVX2: Found an estimated cost of 2 for instruction:   %shift
-; AVX512: Found an estimated cost of 2 for instruction:   %shift
-; XOP: Found an estimated cost of 4 for instruction:   %shift
+; AVX2: Found an estimated cost of 1 for instruction:   %shift
+; AVX512: Found an estimated cost of 1 for instruction:   %shift
+; XOPAVX: Found an estimated cost of 4 for instruction:   %shift
+; XOPAVX2: Found an estimated cost of 1 for instruction:   %shift
   %shift = ashr <16 x i16> %a, <i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3>
   ret <16 x i16> %shift
 }
@@ -590,10 +591,11 @@ define <32 x i16> @splatconstant_shift_v32i16(<32 x i16> %a) {
 ; SSE2: Found an estimated cost of 4 for instruction:   %shift
 ; SSE41: Found an estimated cost of 4 for instruction:   %shift
 ; AVX: Found an estimated cost of 4 for instruction:   %shift
-; AVX2: Found an estimated cost of 4 for instruction:   %shift
-; AVX512F: Found an estimated cost of 4 for instruction:   %shift
+; AVX2: Found an estimated cost of 2 for instruction:   %shift
+; AVX512F: Found an estimated cost of 2 for instruction:   %shift
 ; AVX512BW: Found an estimated cost of 1 for instruction:   %shift
-; XOP: Found an estimated cost of 8 for instruction:   %shift
+; XOPAVX: Found an estimated cost of 8 for instruction:   %shift
+; XOPAVX2: Found an estimated cost of 2 for instruction:   %shift
   %shift = ashr <32 x i16> %a, <i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3>
   ret <32 x i16> %shift
 }

diff --git a/test/Analysis/CostModel/X86/vshift-lshr-cost.ll b/test/Analysis/CostModel/X86/vshift-lshr-cost.ll
index fea7271..c1c6748 100644 (file)
--- a/test/Analysis/CostModel/X86/vshift-lshr-cost.ll
+++ b/test/Analysis/CostModel/X86/vshift-lshr-cost.ll
@@ -589,9 +589,10 @@ define <16 x i16> @splatconstant_shift_v16i16(<16 x i16> %a) {
 ; SSE2: Found an estimated cost of 2 for instruction:   %shift
 ; SSE41: Found an estimated cost of 2 for instruction:   %shift
 ; AVX: Found an estimated cost of 2 for instruction:   %shift
-; AVX2: Found an estimated cost of 2 for instruction:   %shift
-; AVX512: Found an estimated cost of 2 for instruction:   %shift
-; XOP: Found an estimated cost of 4 for instruction:   %shift
+; AVX2: Found an estimated cost of 1 for instruction:   %shift
+; AVX512: Found an estimated cost of 1 for instruction:   %shift
+; XOPAVX: Found an estimated cost of 4 for instruction:   %shift
+; XOPAVX2: Found an estimated cost of 1 for instruction:   %shift
   %shift = lshr <16 x i16> %a, <i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3>
   ret <16 x i16> %shift
 }
@@ -601,10 +602,11 @@ define <32 x i16> @splatconstant_shift_v32i16(<32 x i16> %a) {
 ; SSE2: Found an estimated cost of 4 for instruction:   %shift
 ; SSE41: Found an estimated cost of 4 for instruction:   %shift
 ; AVX: Found an estimated cost of 4 for instruction:   %shift
-; AVX2: Found an estimated cost of 4 for instruction:   %shift
-; AVX512F: Found an estimated cost of 4 for instruction:   %shift
+; AVX2: Found an estimated cost of 2 for instruction:   %shift
+; AVX512F: Found an estimated cost of 2 for instruction:   %shift
 ; AVX512BW: Found an estimated cost of 1 for instruction:   %shift
-; XOP: Found an estimated cost of 8 for instruction:   %shift
+; XOPAVX: Found an estimated cost of 8 for instruction:   %shift
+; XOPAVX2: Found an estimated cost of 2 for instruction:   %shift
   %shift = lshr <32 x i16> %a, <i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3, i16 3>
   ret <32 x i16> %shift
 }