[llvm] [IR] Add nowrap flags for trunc instruction (PR #85592)

[Matt Arsenault via llvm-commits]

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@@ -32,5 +36,9 @@ first:                                            ; preds = %entry
   %rr = zext i32 %ss to i64
   %mm = or disjoint i32 %a, 0
   %nn = or i32 %a, 0
+  %tuu = trunc nuw i32 %a to i16
+  %tss = trunc nsw i32 %a to i16
+  %tuss = trunc nuw nsw i32 %a to i16
+  %tt = trunc i32 %a to i16
   br label %second
 }
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arsenm wrote:

Test vectors? 

https://github.com/llvm/llvm-project/pull/85592