[SLP]Adjust assertion check for scalars in several insertelements.

If the same scalar is inserted several times into the same buildvector,
the mask index can be used already. In this case need to check, that
this scalar is already part of the vectorized buildvector.

diff --git a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
index 4f3db8c..8abe0bd 100644 (file)
--- a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -6592,7 +6592,16 @@ InstructionCost BoUpSLP::getTreeCost(ArrayRef<Value *> VectorizedVals) {
           SmallVectorImpl<int> &Mask = ShuffleMasks[VecId][ScalarTE];
           if (Mask.empty())
             Mask.assign(FTy->getNumElements(), UndefMaskElem);
-          assert(Mask[InIdx] == UndefMaskElem &&
+          // InsertElement should not be used already or the scalar is part of
+          // TreeEntry, which is operand of the root insertelement instructions.
+          assert((Mask[InIdx] == UndefMaskElem ||
+                  any_of(ScalarTE->UserTreeIndices,
+                         [](const EdgeInfo &EI) {
+                           return EI.EdgeIdx == 1 &&
+                                  EI.UserTE->getOpcode() ==
+                                      Instruction::InsertElement &&
+                                  !EI.UserTE->isAltShuffle();
+                         })) &&
                  "InsertElementInstruction used already.");
           Mask[InIdx] = EU.Lane;
           DemandedElts[VecId].setBit(InIdx);

diff --git a/llvm/test/Transforms/SLPVectorizer/X86/buildvector-shuffle.ll b/llvm/test/Transforms/SLPVectorizer/X86/buildvector-shuffle.ll
index 92762dd..fa4fd9d 100644 (file)
--- a/llvm/test/Transforms/SLPVectorizer/X86/buildvector-shuffle.ll
+++ b/llvm/test/Transforms/SLPVectorizer/X86/buildvector-shuffle.ll
@@ -41,3 +41,28 @@ entry:
 }
 
 declare float @llvm.fmuladd.f32(float, float, float)
+
+define void @test(float %a) {
+; CHECK-LABEL: @test(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[TMP0:%.*]] = insertelement <2 x float> poison, float [[A:%.*]], i32 0
+; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <2 x float> [[TMP0]], float [[A]], i32 1
+; CHECK-NEXT:    br label [[LOOP:%.*]]
+; CHECK:       loop:
+; CHECK-NEXT:    [[TMP2:%.*]] = fadd <2 x float> zeroinitializer, [[TMP1]]
+; CHECK-NEXT:    [[TMP3:%.*]] = extractelement <2 x float> [[TMP2]], i32 0
+; CHECK-NEXT:    [[AGG:%.*]] = insertelement <2 x float> [[TMP2]], float [[TMP3]], i64 1
+; CHECK-NEXT:    br label [[LOOP]]
+;
+entry:
+  br label %loop
+
+loop:
+  %add.i157 = fadd float 0.000000e+00, %a
+  %add23.i = fadd float 0.000000e+00, %a
+  %insert = insertelement <2 x float> zeroinitializer, float %add.i157, i64 0
+  %insert.i = insertelement <2 x float> %insert, float %add23.i, i64 1
+  %agg = insertelement <2 x float> %insert.i, float %add.i157, i64 1
+  br label %loop
+}
+