diff --git a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp --- a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp +++ b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp @@ -3307,9 +3307,14 @@ MapVector> OrdersUses; + // Do the analysis for each tree entry only once, otherwise the order of + // the same node my be considered several times, though might be not + // profitable. SmallPtrSet VisitedOps; for (const auto &Op : Data.second) { TreeEntry *OpTE = Op.second; + if (!VisitedOps.insert(OpTE).second) + continue; if (!OpTE->ReuseShuffleIndices.empty() || (IgnoreReorder && OpTE == VectorizableTree.front().get())) continue; @@ -3333,9 +3338,8 @@ } else { ++OrdersUses.insert(std::make_pair(Order, 0)).first->second; } - if (VisitedOps.insert(OpTE).second) - OrdersUses.insert(std::make_pair(OrdersType(), 0)).first->second += - OpTE->UserTreeIndices.size(); + OrdersUses.insert(std::make_pair(OrdersType(), 0)).first->second += + OpTE->UserTreeIndices.size(); assert(OrdersUses[{}] > 0 && "Counter cannot be less than 0."); --OrdersUses[{}]; } @@ -8444,7 +8448,7 @@ if (R.isTreeTinyAndNotFullyVectorizable()) continue; R.reorderTopToBottom(); - R.reorderBottomToTop(); + R.reorderBottomToTop(!isa(Ops.front())); R.buildExternalUses(); R.computeMinimumValueSizes(); diff --git a/llvm/test/Transforms/SLPVectorizer/X86/reordered-top-scalars.ll b/llvm/test/Transforms/SLPVectorizer/X86/reordered-top-scalars.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Transforms/SLPVectorizer/X86/reordered-top-scalars.ll @@ -0,0 +1,43 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt -S --slp-vectorizer -mtriple=x86_64-unknown %s -slp-threshold=-5 | FileCheck %s + +define i32 @test(i32* %isec) { +; CHECK-LABEL: @test( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[ARRAYIDX10:%.*]] = getelementptr inbounds i32, i32* [[ISEC:%.*]], i32 0 +; CHECK-NEXT: [[TMP0:%.*]] = bitcast i32* [[ARRAYIDX10]] to <2 x i32>* +; CHECK-NEXT: [[TMP1:%.*]] = load <2 x i32>, <2 x i32>* [[TMP0]], align 8 +; CHECK-NEXT: [[SHUFFLE:%.*]] = shufflevector <2 x i32> [[TMP1]], <2 x i32> poison, <2 x i32> +; CHECK-NEXT: [[TMP2:%.*]] = extractelement <2 x i32> [[TMP1]], i32 0 +; CHECK-NEXT: [[TMP3:%.*]] = insertelement <2 x i32> poison, i32 [[TMP2]], i32 0 +; CHECK-NEXT: [[TMP4:%.*]] = extractelement <2 x i32> [[TMP1]], i32 1 +; CHECK-NEXT: [[TMP5:%.*]] = insertelement <2 x i32> [[TMP3]], i32 [[TMP4]], i32 1 +; CHECK-NEXT: br i1 false, label [[BLOCK1:%.*]], label [[BLOCK3:%.*]] +; CHECK: block1: +; CHECK-NEXT: br i1 false, label [[BLOCK2:%.*]], label [[BLOCK3]] +; CHECK: block2: +; CHECK-NEXT: br label [[BLOCK3]] +; CHECK: block3: +; CHECK-NEXT: [[TMP6:%.*]] = phi <2 x i32> [ [[SHUFFLE]], [[BLOCK1]] ], [ [[SHUFFLE]], [[BLOCK2]] ], [ [[TMP5]], [[ENTRY:%.*]] ] +; CHECK-NEXT: [[TMP7:%.*]] = extractelement <2 x i32> [[TMP6]], i32 0 +; CHECK-NEXT: [[TMP8:%.*]] = extractelement <2 x i32> [[TMP6]], i32 1 +; CHECK-NEXT: [[TMP9:%.*]] = mul i32 [[TMP7]], [[TMP8]] +; CHECK-NEXT: ret i32 [[TMP9]] +; +entry: + %arrayidx10 = getelementptr inbounds i32, i32* %isec, i32 0 + %0 = bitcast i32* %arrayidx10 to <2 x i32>* + %1 = load <2 x i32>, <2 x i32>* %0, align 8 + %2 = extractelement <2 x i32> %1, i32 1 + %3 = extractelement <2 x i32> %1, i32 0 + br i1 false, label %block1, label %block3 +block1: + br i1 false, label %block2, label %block3 +block2: + br label %block3 +block3: + %4 = phi i32 [ %2, %block1 ], [ %2, %block2 ], [ %3, %entry ] + %5 = phi i32 [ %3, %block1 ], [ %3, %block2 ], [ %2, %entry ] + %6 = mul i32 %4, %5 + ret i32 %6 +}