[llvm] Reland [CGData] llvm-cgdata #89884 (PR #101461)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,28 @@
+include "llvm/Option/OptParser.td"
+
+class F<string letter, string help> : Flag<["-"], letter>, HelpText<help>;
+
+// General options
+def generic_group : OptionGroup<"Genric Options">, HelpText<"Generic Options">;
+def help : F<"help", "Display this help">, Group<generic_group>;
+def : Flag<["-"], "h">, Alias<help>, HelpText<"Alias for --help">, Group<generic_group>;
+def version : F<"version", "Display the version">, Group<generic_group>;
+def : Flag<["-"], "v">, Alias<version>, HelpText<"Alias for --version">, Group<generic_group>;
+
+// Action options
+def action_group : OptionGroup<"Action">, HelpText<"Action (required)">;
+def show : F<"show", "Show summary of the (indexed) codegen data file.">,
+  Group<action_group>;
+def convert : F<"convert", "Convert the (indexed) codegen data file in either text or binary format.">,
+  Group<action_group>;
+def merge : F<"merge", "Takes binary files having raw codegen data in custom sections, and merge them into an index codegen data file.">,
+  Group<action_group>;
+def cgdata_version : Flag<["-", "--"], "cgdata-version">, HelpText<"Display the cgdata version">;
+
+// Output options
+def output : Option<["-", "--"], "output", KIND_SEPARATE>,
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MaskRay wrote:

For new utility with no concern of backward option compatibility, it's recommended to support only `--`

https://github.com/llvm/llvm-project/pull/101461