[clang] [flang] [flang][cuda] Add -fcuda option (PR #84944)

[Andrzej Warzyński via cfe-commits]

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@@ -6488,6 +6488,9 @@ defm stack_arrays : BoolOptionWithoutMarshalling<"f", "stack-arrays",
 defm loop_versioning : BoolOptionWithoutMarshalling<"f", "version-loops-for-stride",
   PosFlag<SetTrue, [], [ClangOption], "Create unit-strided versions of loops">,
    NegFlag<SetFalse, [], [ClangOption], "Do not create unit-strided loops (default)">>;
+
+def fcuda : Flag<["-"], "fcuda">, Group<f_Group>,
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banach-space wrote:

I don't quite understand what actually `-fcuda` enables. Could the flag be more descriptive and the help text expanded? Also, what's the equivalent in Clang? We ought to keep both drivers in sync.

In particular, if this is something specific to Flang then I would avoid generic names like `-fcuda`.

https://github.com/llvm/llvm-project/pull/84944