Re: [PATCH 1/1] RISC-V: Add --march=help

[Hau Hsu <hau.hsu@sifive.com>]

Oh I forgot to change title. There should be only one dash (-march=help) instead of two …
Let me send another patch later.

> Kito Cheng <kito.cheng@gmail.com> 於 2024年2月23日 中午12:25 寫道：
> 
> LGTM, and gcc have landed[1] the same option as well :)
> 
> [1] https://github.com/gcc-mirror/gcc/commit/7af0f1e107a480fbfe882cb985603960114aefb5
> 
> On Wed, Feb 21, 2024 at 11:38 AM Hau Hsu <hau.hsu@sifive.com> wrote:
>> 
>> Use --march=help to print all supported extensions and versions.
>> 
>> Here is part of the output of `as -march=help`:
>> All available -march extensions for RISC-V:
>>        e                                       1.9
>>        i                                       2.1, 2.0
>>        m                                       2.0
>>        a                                       2.1, 2.0
>>        f                                       2.2, 2.0
>>        d                                       2.2, 2.0
>>        q                                       2.2, 2.0
>>        c                                       2.0
>>        v                                       1.0
>>        h                                       1.0
>>        zicbom                                  1.0
>>        zicbop                                  1.0
>> 
>> This patch assumes that the supported extensions with the same versions
>> are listed together.
>> 
>> For example
>> static struct riscv_supported_ext riscv_supported_std_ext[] =
>> {
>>  ...
>>  {"i",         ISA_SPEC_CLASS_20191213,        2, 1, 0 },
>>  {"i",         ISA_SPEC_CLASS_20190608,        2, 1, 0 },
>>  {"i",         ISA_SPEC_CLASS_2P2,             2, 0, 0 },
>>  ...
>> };
>> 
>> For the "i" extension, 2.1.0 with different spec class are listed together.
>> This patch records the previous printed extension and version.  If the
>> current extension and version are the same as the previous one, skip
>> printing.
>> ---
>> bfd/ChangeLog         |  9 ++++++
>> bfd/elfxx-riscv.c     | 64 +++++++++++++++++++++++++++++++++++++++++++
>> bfd/elfxx-riscv.h     |  3 ++
>> gas/ChangeLog         |  4 +++
>> gas/config/tc-riscv.c |  6 ++++
>> 5 files changed, 86 insertions(+)
>> 
>> diff --git a/bfd/ChangeLog b/bfd/ChangeLog
>> index 97d0c585a56..66572927998 100644
>> --- a/bfd/ChangeLog
>> +++ b/bfd/ChangeLog
>> @@ -1,3 +1,12 @@
>> +2024-02-21 Hau Hsu  <hau.hsu@sifive.com>
>> +
>> +       * elfxx-riscv.h (riscv_print_extensions): New declaration.
>> +       * elfxx-riscv.c (riscv_print_extensions): New function. Print
>> +       available extensions and versions.
>> +       (riscv_same_extension_version): New function.
>> +       (riscv_same_extension_diff_version): New function.
>> +       (riscv_valid_ext): New function.
>> +
>> 2024-01-15  Nick Clifton  <nickc@redhat.com>
>> 
>>        * 2.42 branch point.
>> diff --git a/bfd/elfxx-riscv.c b/bfd/elfxx-riscv.c
>> index 9a121b47121..108e26d5b30 100644
>> --- a/bfd/elfxx-riscv.c
>> +++ b/bfd/elfxx-riscv.c
>> @@ -2051,6 +2051,70 @@ riscv_set_default_arch (riscv_parse_subset_t *rps)
>>     }
>> }
>> 
>> +static
>> +bool riscv_same_extension_version(
>> +  const struct riscv_supported_ext* ext1,
>> +  const struct riscv_supported_ext* ext2)
>> +{
>> +  return (strcmp(ext1->name, ext2->name) == 0
>> +          && ext1->major_version == ext2->major_version
>> +          && ext1->minor_version == ext2->minor_version);
>> +}
>> +
>> +static
>> +bool riscv_same_extension_diff_version(
>> +  const struct riscv_supported_ext* ext1,
>> +  const struct riscv_supported_ext* ext2)
>> +{
>> +  return (strcmp(ext1->name, ext2->name) == 0
>> +          && !(ext1->major_version == ext2->major_version
>> +               && ext1->minor_version == ext2->minor_version));
>> +}
>> +
>> +static
>> +bool riscv_valid_ext(const struct riscv_supported_ext *ext)
>> +{
>> +  return (ext->isa_spec_class != ISA_SPEC_CLASS_NONE
>> +          && ext->major_version != RISCV_UNKNOWN_VERSION
>> +          && ext->minor_version != RISCV_UNKNOWN_VERSION);
>> +}
>> +
>> +void riscv_print_extensions(void)
>> +{
>> +  /* Record the previous pritned extension.
>> +     Print the current one if they are not the same.  */
>> +  const struct riscv_supported_ext *cur = NULL, *prev = NULL;
>> +
>> +  int i, j;
>> +  printf ("All available -march extensions for RISC-V:");
>> +  for (i = 0; riscv_all_supported_ext[i] != NULL; i++)
>> +    {
>> +      const struct riscv_supported_ext *exts = riscv_all_supported_ext[i];
>> +      prev = NULL;
>> +      for (j = 0; exts[j].name != NULL; j++)
>> +        {
>> +          cur = &exts[j];
>> +          if (!riscv_valid_ext (cur))
>> +            continue;
>> +
>> +          if (prev && riscv_same_extension_version (prev, cur))
>> +            continue;
>> +
>> +          if (!prev || !riscv_same_extension_diff_version (prev, cur))
>> +            {
>> +              printf("\n\t%-40s%d.%d", cur->name, cur->major_version, cur->minor_version);
>> +              prev = &exts[j];
>> +            }
>> +          else
>> +            {
>> +              printf(", %d.%d", cur->major_version, cur->minor_version);
>> +              prev = &exts[j];
>> +            }
>> +        }
>> +    }
>> +  printf ("\n");
>> +}
>> +
>> /* Function for parsing ISA string.
>> 
>>    Return Value:
>> diff --git a/bfd/elfxx-riscv.h b/bfd/elfxx-riscv.h
>> index ae4cbee7bc3..f3710ec7fab 100644
>> --- a/bfd/elfxx-riscv.h
>> +++ b/bfd/elfxx-riscv.h
>> @@ -121,6 +121,9 @@ riscv_multi_subset_supports (riscv_parse_subset_t *, enum riscv_insn_class);
>> extern const char *
>> riscv_multi_subset_supports_ext (riscv_parse_subset_t *, enum riscv_insn_class);
>> 
>> +extern void
>> +riscv_print_extensions(void);
>> +
>> extern void
>> bfd_elf32_riscv_set_data_segment_info (struct bfd_link_info *, int *);
>> extern void
>> diff --git a/gas/ChangeLog b/gas/ChangeLog
>> index 88e61083c44..cebd9d94ae5 100644
>> --- a/gas/ChangeLog
>> +++ b/gas/ChangeLog
>> @@ -1,3 +1,7 @@
>> +2024-02-21 Hau Hsu  <hau.hsu@sifive.com>
>> +       * gas/config/tc-riscv.c (md_parse_option): Parse 'help' keyword in
>> +       march to print available extensions and versions.
>> +
>> 2024-02-19 Will Hawkins  <hawkinsw@obs.cr>
>> 
>>        * config/tc-bpf.c (parse_expression): Change switch to if so that
>> diff --git a/gas/config/tc-riscv.c b/gas/config/tc-riscv.c
>> index a4161420128..e0910f59157 100644
>> --- a/gas/config/tc-riscv.c
>> +++ b/gas/config/tc-riscv.c
>> @@ -4034,6 +4034,12 @@ md_parse_option (int c, const char *arg)
>>   switch (c)
>>     {
>>     case OPTION_MARCH:
>> +      /* List all avaiable archs. */
>> +      if (strcmp (arg, "help") == 0)
>> +        {
>> +          riscv_print_extensions();
>> +          exit (EXIT_SUCCESS);
>> +        }
>>       default_arch_with_ext = arg;
>>       break;
>> 
>> --
>> 2.31.1
>>