[llvm] select (sext m), (add X, C), X --> (add X, (and C, (sext m)))) (PR #83640)

[Phoebe Wang via llvm-commits]

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@@ -7,6 +7,38 @@
 ; Verify that we don't emit packed vector shifts instructions if the
 ; condition used by the vector select is a vector of constants.
 
+define <2 x i64> @masked_select_const(<2 x i64> %a, <2 x i64> %x, <2 x i64> %y) {
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phoebewang wrote:

Use `<4 x i32>` to avoid unnecessary `bitcast`. And move the test to the end of the file since it's not directly related to above comments.

https://github.com/llvm/llvm-project/pull/83640