[clang] [clang] Add builtins for `add` with `nuw` and/or `nsw` (PR #130354)

[via cfe-commits]

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@@ -5037,6 +5037,66 @@ def ArithmeticFence : LangBuiltin<"ALL_LANGUAGES"> {
   let Prototype = "void(...)";
 }
 
+class SNUWTemplate :
+  Template<["int",      "long int",  "long long int"],
+           ["_nuw",     "l_nuw",     "ll_nuw"]>;
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macurtis-amd wrote:

The intent is to map directly to llvm IR in order to give library writers full control of the generated `add` instruction.

So IMO deviating from the IR terminology would only add confusion.

Similarly, I think making assumptions or restrictions about when `nuw` and `nsw` are applicable might frustrate users who, for whatever reason, just want clang to generate some specific `add` instruction.

https://github.com/llvm/llvm-project/pull/130354