[Bug target/109349] New: Add --print-supported-extensions

[Bug target/109349] New: Add --print-supported-extensions

[i at maskray dot me]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109349

            Bug ID: 109349
           Summary: Add --print-supported-extensions
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: i at maskray dot me
  Target Milestone: ---

Clang may add a RISC-V specific option --print-supported-extensions to list
implemented ISA extensions with the corresponding versions:
https://reviews.llvm.org/D146054

I think it will be nice if GCC and Clang agree on the feature and spelling :)

[Bug target/109349] riscv: Add --print-supported-extensions

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109349

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Target options always start with -m

[Bug target/109349] riscv: Add --print-supported-extensions

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109349

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Also from reading the merge request, this really should just be in the gcc user
manual instead of just in the compiler.

Gcc's user manual should document what is supported.
It is how all other targets handle this.

[Bug target/109349] riscv: Add --print-supported-extensions

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109349

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=106530

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Note I filed PR 106530 for the whole lack of documentation on what is allowed
for -march= for riscv even.  Other targets documentation is so much better in
documenting options.

[Bug target/109349] riscv: Add --print-supported-extensions

[kito at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109349

Kito Cheng <kito at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |kito at gcc dot gnu.org

--- Comment #4 from Kito Cheng <kito at gcc dot gnu.org> ---
MaskRay:

I would prefer to adding -march=help rather than --print-supported-extensions
on GNU toolchain side, that should be satisfy the conventions in GCC and also
having consistent with clang, although I am personally prefer -march=? rather
than -march=help, but I know clang has rename -mcpu=? -mtune=? to -mcpu=help
and -mtune=help, anyway that's minor.

BTW, 4vtomat is our(SiFive) team member, so actually we've plan to add that on
GNU toolchain side but because it's stage 4 for GCC so I still hold there :P


Andrew Pinski:

Yeah, I plan to make up document stuffs and release notes at April...

[Bug target/109349] riscv: Add --print-supported-extensions

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109349

--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Kito Cheng <kito@gcc.gnu.org>:

https://gcc.gnu.org/g:7af0f1e107a480fbfe882cb985603960114aefb5

commit r14-9023-g7af0f1e107a480fbfe882cb985603960114aefb5
Author: Kito Cheng <kito.cheng@sifive.com>
Date:   Fri Jan 19 10:29:10 2024 +0800

    RISC-V: Add new option -march=help to print all supported extensions

    The output of -march=help is like below:

    ```
    All available -march extensions for RISC-V:
            Name                Version
            i                       2.0, 2.1
            e                       2.0
            m                       2.0
            a                       2.0, 2.1
            f                       2.0, 2.2
            d                       2.0, 2.2
    ...
    ```

    Also support -print-supported-extensions and --print-supported-extensions
for
    clang compatibility.

    gcc/ChangeLog:

            PR target/109349

            * common/config/riscv/riscv-common.cc (riscv_arch_help): New.
            * config/riscv/riscv-protos.h (RISCV_MAJOR_VERSION_BASE): New.
            (RISCV_MINOR_VERSION_BASE): Ditto.
            (RISCV_REVISION_VERSION_BASE): Ditto.
            * config/riscv/riscv-c.cc (riscv_ext_version_value): Use enum
            rather than magic number.
            * config/riscv/riscv.h (riscv_arch_help): New.
            (EXTRA_SPEC_FUNCTIONS): Add riscv_arch_help.
            (DRIVER_SELF_SPECS): Handle -march=help,
-print-supported-extensions and
            --print-supported-extensions.
            * config/riscv/riscv.opt (march=help): New.
            (print-supported-extensions): New.
            (-print-supported-extensions): New.
            * doc/invoke.texi (RISC-V Options): Document -march=help.

    Reviewed-by: Christoph Müllner <christoph.muellner@vrull.eu>

[Bug target/109349] riscv: Add --print-supported-extensions

[kito at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109349

Kito Cheng <kito at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|UNCONFIRMED                 |RESOLVED

--- Comment #6 from Kito Cheng <kito at gcc dot gnu.org> ---
Implemented on trunk now :)