[llvm] 557a0be - [InstCombine] Add test for splat shuffle miscompile (NFC)

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2024-05-21T15:21:31+02:00
New Revision: 557a0be3af798cf55b1ef54fc98a84fa5a4ade42

URL: https://github.com/llvm/llvm-project/commit/557a0be3af798cf55b1ef54fc98a84fa5a4ade42
DIFF: https://github.com/llvm/llvm-project/commit/557a0be3af798cf55b1ef54fc98a84fa5a4ade42.diff

LOG: [InstCombine] Add test for splat shuffle miscompile (NFC)

Added: 
    

Modified: 
    llvm/test/Transforms/InstCombine/vec_shuffle.ll

Removed: 
    


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diff  --git a/llvm/test/Transforms/InstCombine/vec_shuffle.ll b/llvm/test/Transforms/InstCombine/vec_shuffle.ll
index d36ada7756af3..7428f7a93d64a 100644
--- a/llvm/test/Transforms/InstCombine/vec_shuffle.ll
+++ b/llvm/test/Transforms/InstCombine/vec_shuffle.ll
@@ -2345,3 +2345,27 @@ define i16 @pr92887(<2 x i16> %v) {
   %extract = extractelement <4 x i16> %shuf, i32 2
   ret i16 %extract
 }
+
+; FIXME: This is a miscompile.
+define <2 x i32> @not_splat_shuffle1(i32 %x) {
+; CHECK-LABEL: @not_splat_shuffle1(
+; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <2 x i32> poison, i32 [[X:%.*]], i64 0
+; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <2 x i32> [[TMP1]], <2 x i32> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    ret <2 x i32> [[SHUF]]
+;
+  %vec = insertelement <2 x i32> undef, i32 %x, i32 1
+  %shuf = shufflevector <2 x i32> %vec, <2 x i32> poison, <2 x i32> <i32 1, i32 0>
+  ret <2 x i32> %shuf
+}
+
+; FIXME: This is a miscompile.
+define <2 x i32> @not_splat_shuffle2(i32 %x) {
+; CHECK-LABEL: @not_splat_shuffle2(
+; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <2 x i32> poison, i32 [[X:%.*]], i64 0
+; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <2 x i32> [[TMP1]], <2 x i32> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT:    ret <2 x i32> [[SHUF]]
+;
+  %vec = insertelement <2 x i32> poison, i32 %x, i32 1
+  %shuf = shufflevector <2 x i32> %vec, <2 x i32> undef, <2 x i32> <i32 1, i32 3>
+  ret <2 x i32> %shuf
+}