[CostModel] Recognise REVERSE shuffle mask if the elements come from the second src

llvm-svn: 334698

diff --git a/llvm/lib/Analysis/TargetTransformInfo.cpp b/llvm/lib/Analysis/TargetTransformInfo.cpp
index a470e97..ca475e8 100644 (file)
--- a/llvm/lib/Analysis/TargetTransformInfo.cpp
+++ b/llvm/lib/Analysis/TargetTransformInfo.cpp
@@ -631,10 +631,17 @@ int TargetTransformInfo::getInstructionLatency(const Instruction *I) const {
 }
 
 static bool isReverseVectorMask(ArrayRef<int> Mask) {
-  for (unsigned i = 0, MaskSize = Mask.size(); i < MaskSize; ++i)
-    if (Mask[i] >= 0 && Mask[i] != (int)(MaskSize - 1 - i))
-      return false;
-  return true;
+  bool ReverseLHS = true;
+  bool ReverseRHS = true;
+  unsigned MaskSize = Mask.size();
+
+  for (unsigned i = 0; i < MaskSize && (ReverseLHS || ReverseRHS); ++i) {
+    if (Mask[i] < 0)
+      continue;
+    ReverseLHS &= (Mask[i] == (int)(MaskSize - 1 - i));
+    ReverseRHS &= (Mask[i] == (int)(MaskSize + MaskSize - 1 - i));
+  }
+  return ReverseLHS || ReverseRHS;
 }
 
 static bool isSingleSourceVectorMask(ArrayRef<int> Mask) {

diff --git a/llvm/test/Analysis/CostModel/X86/shuffle-reverse.ll b/llvm/test/Analysis/CostModel/X86/shuffle-reverse.ll
index e7b0711..d900963 100644 (file)
--- a/llvm/test/Analysis/CostModel/X86/shuffle-reverse.ll
+++ b/llvm/test/Analysis/CostModel/X86/shuffle-reverse.ll
@@ -306,22 +306,22 @@ define void @test_upper_vXf32(<2 x float> %a64, <2 x float> %b64, <4 x float> %a
 ; SSE-LABEL: 'test_upper_vXf32'
 ; SSE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %V64 = shufflevector <2 x float> %a64, <2 x float> %b64, <2 x i32> <i32 3, i32 2>
 ; SSE-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %V128 = shufflevector <4 x float> %a128, <4 x float> %b128, <4 x i32> <i32 7, i32 6, i32 5, i32 4>
-; SSE-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %V256 = shufflevector <8 x float> %a256, <8 x float> %b256, <8 x i32> <i32 15, i32 14, i32 13, i32 12, i32 11, i32 10, i32 9, i32 8>
-; SSE-NEXT:  Cost Model: Found an estimated cost of 24 for instruction: %V512 = shufflevector <16 x float> %a512, <16 x float> %b512, <16 x i32> <i32 31, i32 30, i32 29, i32 28, i32 27, i32 26, i32 25, i32 24, i32 23, i32 22, i32 21, i32 20, i32 19, i32 18, i32 17, i32 16>
+; SSE-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %V256 = shufflevector <8 x float> %a256, <8 x float> %b256, <8 x i32> <i32 15, i32 14, i32 13, i32 12, i32 11, i32 10, i32 9, i32 8>
+; SSE-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %V512 = shufflevector <16 x float> %a512, <16 x float> %b512, <16 x i32> <i32 31, i32 30, i32 29, i32 28, i32 27, i32 26, i32 25, i32 24, i32 23, i32 22, i32 21, i32 20, i32 19, i32 18, i32 17, i32 16>
 ; SSE-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void
 ;
 ; AVX1-LABEL: 'test_upper_vXf32'
 ; AVX1-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %V64 = shufflevector <2 x float> %a64, <2 x float> %b64, <2 x i32> <i32 3, i32 2>
 ; AVX1-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %V128 = shufflevector <4 x float> %a128, <4 x float> %b128, <4 x i32> <i32 7, i32 6, i32 5, i32 4>
-; AVX1-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %V256 = shufflevector <8 x float> %a256, <8 x float> %b256, <8 x i32> <i32 15, i32 14, i32 13, i32 12, i32 11, i32 10, i32 9, i32 8>
-; AVX1-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %V512 = shufflevector <16 x float> %a512, <16 x float> %b512, <16 x i32> <i32 31, i32 30, i32 29, i32 28, i32 27, i32 26, i32 25, i32 24, i32 23, i32 22, i32 21, i32 20, i32 19, i32 18, i32 17, i32 16>
+; AVX1-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %V256 = shufflevector <8 x float> %a256, <8 x float> %b256, <8 x i32> <i32 15, i32 14, i32 13, i32 12, i32 11, i32 10, i32 9, i32 8>
+; AVX1-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %V512 = shufflevector <16 x float> %a512, <16 x float> %b512, <16 x i32> <i32 31, i32 30, i32 29, i32 28, i32 27, i32 26, i32 25, i32 24, i32 23, i32 22, i32 21, i32 20, i32 19, i32 18, i32 17, i32 16>
 ; AVX1-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void
 ;
 ; AVX2-LABEL: 'test_upper_vXf32'
 ; AVX2-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %V64 = shufflevector <2 x float> %a64, <2 x float> %b64, <2 x i32> <i32 3, i32 2>
 ; AVX2-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %V128 = shufflevector <4 x float> %a128, <4 x float> %b128, <4 x i32> <i32 7, i32 6, i32 5, i32 4>
 ; AVX2-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %V256 = shufflevector <8 x float> %a256, <8 x float> %b256, <8 x i32> <i32 15, i32 14, i32 13, i32 12, i32 11, i32 10, i32 9, i32 8>
-; AVX2-NEXT:  Cost Model: Found an estimated cost of 6 for instruction: %V512 = shufflevector <16 x float> %a512, <16 x float> %b512, <16 x i32> <i32 31, i32 30, i32 29, i32 28, i32 27, i32 26, i32 25, i32 24, i32 23, i32 22, i32 21, i32 20, i32 19, i32 18, i32 17, i32 16>
+; AVX2-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %V512 = shufflevector <16 x float> %a512, <16 x float> %b512, <16 x i32> <i32 31, i32 30, i32 29, i32 28, i32 27, i32 26, i32 25, i32 24, i32 23, i32 22, i32 21, i32 20, i32 19, i32 18, i32 17, i32 16>
 ; AVX2-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void
 ;
 ; AVX512-LABEL: 'test_upper_vXf32'
@@ -334,8 +334,8 @@ define void @test_upper_vXf32(<2 x float> %a64, <2 x float> %b64, <4 x float> %a
 ; BTVER2-LABEL: 'test_upper_vXf32'
 ; BTVER2-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %V64 = shufflevector <2 x float> %a64, <2 x float> %b64, <2 x i32> <i32 3, i32 2>
 ; BTVER2-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %V128 = shufflevector <4 x float> %a128, <4 x float> %b128, <4 x i32> <i32 7, i32 6, i32 5, i32 4>
-; BTVER2-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %V256 = shufflevector <8 x float> %a256, <8 x float> %b256, <8 x i32> <i32 15, i32 14, i32 13, i32 12, i32 11, i32 10, i32 9, i32 8>
-; BTVER2-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %V512 = shufflevector <16 x float> %a512, <16 x float> %b512, <16 x i32> <i32 31, i32 30, i32 29, i32 28, i32 27, i32 26, i32 25, i32 24, i32 23, i32 22, i32 21, i32 20, i32 19, i32 18, i32 17, i32 16>
+; BTVER2-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %V256 = shufflevector <8 x float> %a256, <8 x float> %b256, <8 x i32> <i32 15, i32 14, i32 13, i32 12, i32 11, i32 10, i32 9, i32 8>
+; BTVER2-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %V512 = shufflevector <16 x float> %a512, <16 x float> %b512, <16 x i32> <i32 31, i32 30, i32 29, i32 28, i32 27, i32 26, i32 25, i32 24, i32 23, i32 22, i32 21, i32 20, i32 19, i32 18, i32 17, i32 16>
 ; BTVER2-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void
 ;
   %V64 = shufflevector <2 x float> %a64, <2 x float> %b64, <2 x i32> <i32 3, i32 2>