[llvm] [InstCombine] Detect uadd with overflow idiom (PR #140178)

[via llvm-commits]

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@@ -2350,4 +2350,57 @@ define i8 @fold_add_umax_to_usub_multiuse(i8 %a) {
   ret i8 %sel
 }
 
+define i32 @uadd_with_zext(i32 %x, i32 %y) {
+; CHECK-LABEL: @uadd_with_zext(
+; CHECK-NEXT:    [[COND:%.*]] = call i32 @llvm.uadd.sat.i32(i32 [[X:%.*]], i32 [[Y:%.*]])
+; CHECK-NEXT:    ret i32 [[COND]]
+;
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AZero13 wrote:

Well, that's how instcombine is folding it.

What I do only generates the add and compare.

Other folds are folding it further that I don't have any part of

https://github.com/llvm/llvm-project/pull/140178