[llvm] d9c9326 - [SLP]Recalculate number of parts when requesting number of elements based on original scalars size

[Alexey Bataev via llvm-commits]

Author: Alexey Bataev
Date: 2025-01-31T12:55:03-08:00
New Revision: d9c9326a219a87620ff08bf1202441acb2dded2e

URL: https://github.com/llvm/llvm-project/commit/d9c9326a219a87620ff08bf1202441acb2dded2e
DIFF: https://github.com/llvm/llvm-project/commit/d9c9326a219a87620ff08bf1202441acb2dded2e.diff

LOG: [SLP]Recalculate number of parts when requesting number of elements based on original scalars size

Need to recalculate number of parts, since gathered scalar size might be changed
during building the buildvector shuffles.

Fixes #125259

Added: 
    

Modified: 
    llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
    llvm/test/Transforms/SLPVectorizer/X86/gathered-shuffle-resized.ll

Removed: 
    


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diff  --git a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
index 0a3f575915952f..da073f38b53fb2 100644
--- a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -15094,7 +15094,9 @@ ResTy BoUpSLP::processBuildVector(const TreeEntry *E, Type *ScalarTy,
       }
     }
     if (!GatherShuffles.empty()) {
-      unsigned SliceSize = getPartNumElems(E->Scalars.size(), NumParts);
+      unsigned SliceSize =
+          getPartNumElems(E->Scalars.size(),
+                          ::getNumberOfParts(*TTI, VecTy, E->Scalars.size()));
       SmallVector<int> VecMask(Mask.size(), PoisonMaskElem);
       for (const auto [I, TEs] : enumerate(Entries)) {
         if (TEs.empty()) {

diff  --git a/llvm/test/Transforms/SLPVectorizer/X86/gathered-shuffle-resized.ll b/llvm/test/Transforms/SLPVectorizer/X86/gathered-shuffle-resized.ll
index f41d78516be640..48b04201d1acce 100644
--- a/llvm/test/Transforms/SLPVectorizer/X86/gathered-shuffle-resized.ll
+++ b/llvm/test/Transforms/SLPVectorizer/X86/gathered-shuffle-resized.ll
@@ -18,9 +18,9 @@ define ptr @test(ptr %0, ptr %args_gep) {
 ; CHECK-NEXT:    [[TMP8:%.*]] = load i32, ptr [[TMP7]], align 4, !noalias [[META0:![0-9]+]]
 ; CHECK-NEXT:    [[TMP9:%.*]] = load <2 x i32>, ptr [[TMP6]], align 8, !noalias [[META0]]
 ; CHECK-NEXT:    [[TMP10:%.*]] = shufflevector <2 x i32> [[TMP1]], <2 x i32> poison, <4 x i32> <i32 0, i32 1, i32 poison, i32 poison>
-; CHECK-NEXT:    [[TMP11:%.*]] = shufflevector <2 x i32> [[TMP9]], <2 x i32> poison, <16 x i32> poison
+; CHECK-NEXT:    [[TMP11:%.*]] = shufflevector <2 x i32> [[TMP9]], <2 x i32> poison, <16 x i32> <i32 poison, i32 poison, i32 0, i32 1, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison>
 ; CHECK-NEXT:    [[TMP12:%.*]] = shufflevector <4 x i32> [[TMP10]], <4 x i32> poison, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison>
-; CHECK-NEXT:    [[TMP13:%.*]] = shufflevector <2 x i32> [[TMP1]], <2 x i32> [[TMP9]], <16 x i32> <i32 0, i32 1, i32 1, i32 1, i32 1, i32 1, i32 1, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison>
+; CHECK-NEXT:    [[TMP13:%.*]] = shufflevector <2 x i32> [[TMP1]], <2 x i32> [[TMP9]], <16 x i32> <i32 0, i32 1, i32 1, i32 1, i32 1, i32 1, i32 1, i32 2, i32 2, i32 2, i32 2, i32 2, i32 2, i32 3, i32 3, i32 3>
 ; CHECK-NEXT:    [[TMP14:%.*]] = icmp eq <16 x i32> [[TMP13]], zeroinitializer
 ; CHECK-NEXT:    [[TMP15:%.*]] = zext <16 x i1> [[TMP14]] to <16 x i8>
 ; CHECK-NEXT:    store <16 x i8> [[TMP15]], ptr [[TMP5]], align 1