[llvm] [VPlan] Handle WidenCast in isSingleScalar (PR #162340)

[Ramkumar Ramachandra via llvm-commits]

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@@ -18,8 +18,9 @@ define void @minbw_cast(ptr %dst, i64 %n, i1 %bool1, i1 %bool2) {
 ; CHECK-NEXT:    [[BROADCAST_SPLAT2:%.*]] = shufflevector <4 x i32> [[BROADCAST_SPLATINSERT1]], <4 x i32> poison, <4 x i32> zeroinitializer
 ; CHECK-NEXT:    [[TMP0:%.*]] = trunc <4 x i32> [[BROADCAST_SPLAT2]] to <4 x i8>
 ; CHECK-NEXT:    [[TMP1:%.*]] = zext <4 x i1> [[BROADCAST_SPLAT]] to <4 x i8>
-; CHECK-NEXT:    [[TMP2:%.*]] = xor <4 x i8> [[TMP0]], [[TMP1]]
-; CHECK-NEXT:    [[TMP3:%.*]] = extractelement <4 x i8> [[TMP2]], i32 3
+; CHECK-NEXT:    [[TMP2:%.*]] = extractelement <4 x i8> [[TMP0]], i32 0
+; CHECK-NEXT:    [[TMP5:%.*]] = extractelement <4 x i8> [[TMP1]], i32 0
+; CHECK-NEXT:    [[TMP3:%.*]] = xor i8 [[TMP2]], [[TMP5]]
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artagnon wrote:

Yeah, I noticed this too, but isn't the change technically correct? I wonder what we should do?

https://github.com/llvm/llvm-project/pull/162340