Re: [PATCH] RISC-V: Update multilib-generator to handle V

[Palmer Dabbelt <palmer@rivosinc.com>]

On Tue, 18 Apr 2023 18:26:18 PDT (-0700), Kito Cheng wrote:
> And which -march -mabi you used will got issue?
>
> On Wed, Apr 19, 2023 at 8:51 AM Palmer Dabbelt <palmer@rivosinc.com> wrote:
>>
>> On Tue, 18 Apr 2023 17:47:31 PDT (-0700), Kito Cheng wrote:
>> > Do you mind shared gcc configure and the option you tried?
>>
>> Just riscv-gnu-toolchain with "--enbale-multilib --enable-linux".
>>
>> > On Wed, Apr 19, 2023 at 4:01 AM Palmer Dabbelt <palmer@rivosinc.com> wrote:
>> >>
>> >> On Tue, 18 Apr 2023 08:44:24 PDT (-0700), gcc-patches@gcc.gnu.org wrote:
>> >> >> Yep, if I drop the non-canonicial strings via
>> >> >>
>> >> >>     diff --git a/gcc/config/riscv/multilib-generator b/gcc/config/riscv/multilib-generator
>> >> >>     index 58b7198b243..a63a4d69c18 100755
>> >> >>     --- a/gcc/config/riscv/multilib-generator
>> >> >>     +++ b/gcc/config/riscv/multilib-generator
>> >> >>     @@ -174,7 +174,7 @@ for cmodel in cmodels:
>> >> >>          ext_combs = expand_combination(ext)
>> >> >>          alts = sum([[x] + [x + y for y in ext_combs] for x in [arch] + extra], [])
>> >> >>          alts = filter(lambda x: len(x) != 0, alts)
>> >> >>     -    alts = alts + list(map(lambda a : arch_canonicalize(a, args.misa_spec), alts))
>> >> >>     +    alts = list(map(lambda a : arch_canonicalize(a, args.misa_spec), alts))
>> >> >>
>> >> >>          # Drop duplicated entry.
>> >> >>          alts = unique(alts)
>> >> >>
>> >> >> then I can't link `-march=rv32imafdcv`, I need
>> >> >> `-march=rv32imacv_zicsr_zve32f_zve32x_zve64x_zvl128b_zvl32b_zvl64b`.  That's
>> >> >> kind of a headache for users to type in.
>> >> >
>> >> > Yes, that's a headache for users, but arch string canonicalization is
>> >> > hiddened at the process,
>> >> > so the user could still just use rv32imafdcv at compile time and
>> >> > multi-lib config.
>> >> >
>> >> > And the driver and multilib-generator (with arch_canonicalize) script
>> >> > will handle those headache in the background.
>> >>
>> >> Sorry, I'm not exactly sure what you're trying to say.  I just rebuilt
>> >> GCC with this patch (and t-linux-multilib regenerated from it), it's not
>> >> resolving multlibs for the short names.

`-march=rv32imafdcv` is the broken one, 
`-march=rv32imacv_zicsr_zve32f_zve32x_zve64x_zvl128b_zvl32b_zvl64b` 
resolves multilibs (there's a bit more above).