[llvm] [GlobalISel] Make scalar G_SHUFFLE_VECTOR illegal. (PR #140508)

[Matt Arsenault via llvm-commits]

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@@ -52,8 +52,13 @@ body:             |
     ; CHECK: Bad machine code: G_SHUFFLE_VECTOR cannot change element type
     %21:_(s16) = G_SHUFFLE_VECTOR %3, %4, shufflemask(0)
 
+    ; CHECK: Bad machine code: G_SHUFFLE_VECTOR must have vector src
+    %22:_(<2 x s32>) = G_SHUFFLE_VECTOR %3, %4, shufflemask(0, 0)
+
+    ; CHECK: Bad machine code: G_SHUFFLE_VECTOR must have vector dst
+    %23:_(s32) = G_SHUFFLE_VECTOR %0, %1, shufflemask(0)
+
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arsenm wrote:

Check a single element pointer too 

https://github.com/llvm/llvm-project/pull/140508