[llvm-branch-commits] [llvm] db90099 - [CostModel][X86] getGatherScatterOpCost - use default implementation for alt costkinds

[Simon Pilgrim via llvm-branch-commits]

Author: Simon Pilgrim
Date: 2020-12-06T14:08:26Z
New Revision: db900995ed15155062dec217569dbbffb6f49911

URL: https://github.com/llvm/llvm-project/commit/db900995ed15155062dec217569dbbffb6f49911
DIFF: https://github.com/llvm/llvm-project/commit/db900995ed15155062dec217569dbbffb6f49911.diff

LOG: [CostModel][X86] getGatherScatterOpCost - use default implementation for alt costkinds

Noticed while looking at D92701 - we only really handle TCK_RecipThroughput gather/scatter costs - for now drop back to the default implementation for non-legal gathers/scatters.

Added: 
    

Modified: 
    llvm/lib/Target/X86/X86TargetTransformInfo.cpp
    llvm/test/Analysis/CostModel/X86/intrinsic-cost-kinds.ll

Removed: 
    


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diff  --git a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
index 36a04a850110..6a52714fee41 100644
--- a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
+++ b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -4087,7 +4087,8 @@ int X86TTIImpl::getScatterOverhead() const {
   return 1024;
 }
 
-// Return an average cost of Gather / Scatter instruction, maybe improved later
+// Return an average cost of Gather / Scatter instruction, maybe improved later.
+// FIXME: Add TargetCostKind support.
 int X86TTIImpl::getGSVectorCost(unsigned Opcode, Type *SrcVTy, const Value *Ptr,
                                 Align Alignment, unsigned AddressSpace) {
 
@@ -4160,6 +4161,7 @@ int X86TTIImpl::getGSVectorCost(unsigned Opcode, Type *SrcVTy, const Value *Ptr,
 /// Alignment - Alignment for one element.
 /// AddressSpace - pointer[s] address space.
 ///
+/// FIXME: Add TargetCostKind support.
 int X86TTIImpl::getGSScalarCost(unsigned Opcode, Type *SrcVTy,
                                 bool VariableMask, Align Alignment,
                                 unsigned AddressSpace) {
@@ -4206,9 +4208,15 @@ int X86TTIImpl::getGatherScatterOpCost(unsigned Opcode, Type *SrcVTy,
                                        Align Alignment,
                                        TTI::TargetCostKind CostKind,
                                        const Instruction *I = nullptr) {
-
-  if (CostKind != TTI::TCK_RecipThroughput)
-    return 1;
+  if (CostKind != TTI::TCK_RecipThroughput) {
+    if ((Opcode == Instruction::Load &&
+         isLegalMaskedGather(SrcVTy, Align(Alignment))) ||
+        (Opcode == Instruction::Store &&
+         isLegalMaskedScatter(SrcVTy, Align(Alignment))))
+      return 1;
+    return BaseT::getGatherScatterOpCost(Opcode, SrcVTy, Ptr, VariableMask,
+                                         Alignment, CostKind, I);
+  }
 
   assert(SrcVTy->isVectorTy() && "Unexpected data type for Gather/Scatter");
   unsigned VF = cast<FixedVectorType>(SrcVTy)->getNumElements();

diff  --git a/llvm/test/Analysis/CostModel/X86/intrinsic-cost-kinds.ll b/llvm/test/Analysis/CostModel/X86/intrinsic-cost-kinds.ll
index 4d0dbe544fb5..08d4a46896fe 100644
--- a/llvm/test/Analysis/CostModel/X86/intrinsic-cost-kinds.ll
+++ b/llvm/test/Analysis/CostModel/X86/intrinsic-cost-kinds.ll
@@ -289,11 +289,11 @@ define void @maskedgather(<16 x float*> %va, <16 x i1> %vb, <16 x float> %vc) {
 ; LATE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: ret void
 ;
 ; SIZE-LABEL: 'maskedgather'
-; SIZE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v = call <16 x float> @llvm.masked.gather.v16f32.v16p0f32(<16 x float*> %va, i32 1, <16 x i1> %vb, <16 x float> %vc)
+; SIZE-NEXT:  Cost Model: Found an estimated cost of 76 for instruction: %v = call <16 x float> @llvm.masked.gather.v16f32.v16p0f32(<16 x float*> %va, i32 1, <16 x i1> %vb, <16 x float> %vc)
 ; SIZE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: ret void
 ;
 ; SIZE_LATE-LABEL: 'maskedgather'
-; SIZE_LATE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v = call <16 x float> @llvm.masked.gather.v16f32.v16p0f32(<16 x float*> %va, i32 1, <16 x i1> %vb, <16 x float> %vc)
+; SIZE_LATE-NEXT:  Cost Model: Found an estimated cost of 76 for instruction: %v = call <16 x float> @llvm.masked.gather.v16f32.v16p0f32(<16 x float*> %va, i32 1, <16 x i1> %vb, <16 x float> %vc)
 ; SIZE_LATE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: ret void
 ;
   %v = call <16 x float> @llvm.masked.gather.v16f32.v16p0f32(<16 x float*> %va, i32 1, <16 x i1> %vb, <16 x float> %vc)
@@ -310,11 +310,11 @@ define void @maskedscatter(<16 x float> %va, <16 x float*> %vb, <16 x i1> %vc) {
 ; LATE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: ret void
 ;
 ; SIZE-LABEL: 'maskedscatter'
-; SIZE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: call void @llvm.masked.scatter.v16f32.v16p0f32(<16 x float> %va, <16 x float*> %vb, i32 1, <16 x i1> %vc)
+; SIZE-NEXT:  Cost Model: Found an estimated cost of 76 for instruction: call void @llvm.masked.scatter.v16f32.v16p0f32(<16 x float> %va, <16 x float*> %vb, i32 1, <16 x i1> %vc)
 ; SIZE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: ret void
 ;
 ; SIZE_LATE-LABEL: 'maskedscatter'
-; SIZE_LATE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: call void @llvm.masked.scatter.v16f32.v16p0f32(<16 x float> %va, <16 x float*> %vb, i32 1, <16 x i1> %vc)
+; SIZE_LATE-NEXT:  Cost Model: Found an estimated cost of 76 for instruction: call void @llvm.masked.scatter.v16f32.v16p0f32(<16 x float> %va, <16 x float*> %vb, i32 1, <16 x i1> %vc)
 ; SIZE_LATE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: ret void
 ;
   call void @llvm.masked.scatter.v16f32.v16p0f32(<16 x float> %va, <16 x float*> %vb, i32 1, <16 x i1> %vc)