[clang] [llvm] [clang] Add cc1 --output-asm-variant= to set output syntax (PR #109360)

[Martin Storsjö via llvm-commits]

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@@ -7209,6 +7209,9 @@ def fuse_ctor_homing: Flag<["-"], "fuse-ctor-homing">,
 def as_secure_log_file : Separate<["-"], "as-secure-log-file">,
   HelpText<"Emit .secure_log_unique directives to this filename.">,
   MarshallingInfoString<CodeGenOpts<"AsSecureLogFile">>;
+def output_asm_variant : Joined<["--"], "output-asm-variant=">,
+  HelpText<"Select the asm variant (integer) to use for output">,
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mstorsjo wrote:

Requiring the user to pick a variant via an integer index feels a bit user-unfriendly - should/could we expose this with names like `=intel` and `=att` like we do for the other related options? Admittedly, this is not a very user facing option, as it is a`-cc1` option only, if I'm correctly understanding the situation, but nevertheless, I wouldn't offhand have any idea about what indices to use here.

https://github.com/llvm/llvm-project/pull/109360