[llvm] [DAG] Extend input types if needed in combineShiftToAVG. (PR #76791)

[Matt Arsenault via llvm-commits]

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@@ -1392,6 +1392,24 @@ define <8 x i8> @sextmask3v8i8(<8 x i16> %src1, <8 x i8> %src2) {
   ret <8 x i8> %result
 }
 
+define <4 x i16> @ext_via_i19(i64 %0, <4 x i16> %1) {
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arsenm wrote:

Avoid anonymous values in tests 

https://github.com/llvm/llvm-project/pull/76791