[PATCH] RISC-V: Support to parse the multi-letter prefix in the architecture string.

[Nelson Chu]

On Fri, Apr 9, 2021 at 2:11 AM Jim Wilson <jimw@sifive.com> wrote:
>
> On Wed, Apr 7, 2021 at 2:25 AM Nelson Chu <nelson.chu@sifive.com> wrote:
>>
>> I never considered the prefixes may have multiple letters, like zxm.
>> But the ISA spec has been updated for a long time that I haven't noticed.
>> This patch rewrites the part of architecture parser to support parsing
>> the multi-letter prefixes.  Besides, I also improve the parser to report
>> errors in details.  One of the most obvious improvement is - Do not parse
>> the prefixed extensions according to the orders in the parse_config.
>> If we do so, then we used to get "unexpected ISA string at end" errors,
>> but the message is a little bit  hard to know what is happening.  I Remove
>> the confused message, and let riscv_parse_prefixed_ext to report the details.
>
>
> Looks reasonable.  We will need a similar patch for gcc, but we don't need it now.

Committed, thanks.