[llvm] 45d82f3 - [SLP]Fix miscompilation, cause by incorrect final node reordering.

[Alexey Bataev via llvm-commits]

Author: Alexey Bataev
Date: 2024-02-29T11:21:06-08:00
New Revision: 45d82f33af9334907dde39cc69921c679299114e

URL: https://github.com/llvm/llvm-project/commit/45d82f33af9334907dde39cc69921c679299114e
DIFF: https://github.com/llvm/llvm-project/commit/45d82f33af9334907dde39cc69921c679299114e.diff

LOG: [SLP]Fix miscompilation, cause by incorrect final node reordering.

Need to use the regular reordering from the correct node for the final
store/insertelement node to avoid miscommilation.

Added: 
    

Modified: 
    llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
    llvm/test/Transforms/SLPVectorizer/X86/reorder-node.ll

Removed: 
    


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diff  --git a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
index 2b7d518c1c1a78..94b7c4952f055e 100644
--- a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -5158,7 +5158,7 @@ void BoUpSLP::reorderBottomToTop(bool IgnoreReorder) {
           OrderedEntries.insert(Data.first);
         }
       } else {
-        reorderOrder(Data.first->ReorderIndices, Mask, /*BottomOrder=*/true);
+        reorderOrder(Data.first->ReorderIndices, Mask);
       }
     }
   }
@@ -8102,7 +8102,7 @@ const BoUpSLP::TreeEntry *BoUpSLP::getOperandEntry(const TreeEntry *E,
                                                    unsigned Idx) const {
   Value *Op = E->getOperand(Idx).front();
   if (const TreeEntry *TE = getTreeEntry(Op)) {
-    if (find_if(E->UserTreeIndices, [&](const EdgeInfo &EI) {
+    if (find_if(TE->UserTreeIndices, [&](const EdgeInfo &EI) {
           return EI.EdgeIdx == Idx && EI.UserTE == E;
         }) != TE->UserTreeIndices.end())
       return TE;

diff  --git a/llvm/test/Transforms/SLPVectorizer/X86/reorder-node.ll b/llvm/test/Transforms/SLPVectorizer/X86/reorder-node.ll
index c45e1e8b17bf8c..1940e1bc8d18ac 100644
--- a/llvm/test/Transforms/SLPVectorizer/X86/reorder-node.ll
+++ b/llvm/test/Transforms/SLPVectorizer/X86/reorder-node.ll
@@ -14,7 +14,7 @@ define void @test(ptr noalias %arg, ptr noalias %arg1, ptr %arg2) {
 ; CHECK-NEXT:    [[TMP3:%.*]] = shufflevector <4 x float> [[TMP0]], <4 x float> poison, <4 x i32> <i32 2, i32 3, i32 2, i32 3>
 ; CHECK-NEXT:    [[TMP4:%.*]] = shufflevector <4 x float> [[TMP0]], <4 x float> poison, <4 x i32> <i32 0, i32 1, i32 0, i32 1>
 ; CHECK-NEXT:    [[TMP5:%.*]] = select <4 x i1> [[TMP2]], <4 x float> [[TMP3]], <4 x float> [[TMP4]]
-; CHECK-NEXT:    [[TMP6:%.*]] = shufflevector <4 x float> [[TMP5]], <4 x float> poison, <4 x i32> <i32 1, i32 2, i32 3, i32 0>
+; CHECK-NEXT:    [[TMP6:%.*]] = shufflevector <4 x float> [[TMP5]], <4 x float> poison, <4 x i32> <i32 2, i32 0, i32 3, i32 1>
 ; CHECK-NEXT:    store <4 x float> [[TMP6]], ptr [[TMP_I_I4]], align 8
 ; CHECK-NEXT:    ret void
 ;