[llvm] [GlobalIsel] Combine ADDO (PR #82927)

[Sergei Barannikov via llvm-commits]

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@@ -1260,6 +1254,12 @@ def match_ors : GICombineRule<
         [{ return Helper.matchOr(*${root}, ${matchinfo}); }]),
   (apply [{ Helper.applyBuildFn(*${root}, ${matchinfo}); }])>;
 
+def match_addos : GICombineRule<
+  (defs root:$root, build_fn_matchinfo:$matchinfo),
+  (match (wip_match_opcode G_SADDO, G_UADDO):$root,
+        [{ return Helper.matchAddOverflow(*${root}, ${matchinfo}); }]),
+  (apply [{ Helper.applyBuildFn(*${root}, ${matchinfo}); }])>;
+
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s-barannikov wrote:

I don't know about the current direction, but if we're going to tablegen as much as possible, then we would need separate rules for each of the transformations (constant folding / swapping constant to RHS / replacing with G_ADD etc.).


https://github.com/llvm/llvm-project/pull/82927