diff --git a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
index 2efe107..444bd08 100644
--- a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -10617,7 +10617,11 @@
                                /*IsStrict=*/true) ||
                 (Shuffle && Mask.size() == Shuffle->getShuffleMask().size() &&
                  Shuffle->isZeroEltSplat() &&
-                 ShuffleVectorInst::isZeroEltSplatMask(Mask, Mask.size())));
+                 ShuffleVectorInst::isZeroEltSplatMask(Mask, Mask.size()) &&
+                 all_of(enumerate(Mask), [&](const auto &P) {
+                   return P.value() == PoisonMaskElem ||
+                          Shuffle->getShuffleMask()[P.index()] == 0;
+                 })));
       }
       V = Op;
       return false;
diff --git a/llvm/test/Transforms/SLPVectorizer/X86/identity-match-splat-less-defined.ll b/llvm/test/Transforms/SLPVectorizer/X86/identity-match-splat-less-defined.ll
index d6449c5..d6f0b76 100644
--- a/llvm/test/Transforms/SLPVectorizer/X86/identity-match-splat-less-defined.ll
+++ b/llvm/test/Transforms/SLPVectorizer/X86/identity-match-splat-less-defined.ll
@@ -7,7 +7,8 @@
 ; CHECK-NEXT:    [[TMP2:%.*]] = shufflevector <4 x i32> [[TMP1]], <4 x i32> poison, <4 x i32> <i32 0, i32 0, i32 0, i32 poison>
 ; CHECK-NEXT:    [[TMP3:%.*]] = or <4 x i32> [[TMP2]], <i32 0, i32 0, i32 0, i32 poison>
 ; CHECK-NEXT:    [[TMP4:%.*]] = shufflevector <4 x i32> [[TMP3]], <4 x i32> poison, <16 x i32> <i32 0, i32 1, i32 1, i32 1, i32 1, i32 1, i32 1, i32 1, i32 1, i32 1, i32 2, i32 2, i32 2, i32 2, i32 2, i32 2>
-; CHECK-NEXT:    [[TMP5:%.*]] = or <4 x i32> [[TMP2]], zeroinitializer
+; CHECK-NEXT:    [[TMP25:%.*]] = shufflevector <4 x i32> [[TMP2]], <4 x i32> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP5:%.*]] = or <4 x i32> [[TMP25]], zeroinitializer
 ; CHECK-NEXT:    [[TMP6:%.*]] = shufflevector <4 x i32> [[TMP5]], <4 x i32> poison, <24 x i32> <i32 0, i32 0, i32 1, i32 1, i32 1, i32 1, 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 2, i32 2, i32 2, i32 3, i32 3, i32 3>
 ; CHECK-NEXT:    [[TMP7:%.*]] = shufflevector <4 x i32> [[TMP3]], <4 x i32> poison, <64 x i32> <i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, 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:    [[TMP8:%.*]] = shufflevector <4 x i32> [[TMP5]], <4 x i32> poison, <64 x i32> <i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 3, i32 3, i32 3, 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>