target/sparc: Relax some decode for v7/v8

[PATCH v2 0/7] target/sparc: Relax some decode for v7/v8

Posted by Richard Henderson 5 months, 1 week ago

Hi Mark,

I noticed a few other places where we probably want to
allow unused bits to be set and ignored for pre-v9.

Changes for v2:
  - Use TRANS() in the STBAR and RDY patches.
  - Apply the same relaxation for RDPSR, RDWIM, RDTBR.
  - Do not report illegal_instruction when unused bits
    are set in the rs2_or_imm field.

r~


Supercedes: 20250905051936.92815-1-richard.henderson@linaro.org

Richard Henderson (7):
  target/sparc: Allow TRANS macro with no extra arguments
  target/sparc: Loosen decode of STBAR for v8
  target/sparc: Loosen decode of RDY for v7
  target/sparc: Loosen decode of RDPSR for v7
  target/sparc: Loosen decode of RDWIM for v7
  target/sparc: Loosen decode of RDTBR for v7
  target/sparc: Relax decode of rs2_or_imm for v7

 target/sparc/translate.c  | 77 ++++++++++++++++++++----------------
 target/sparc/insns.decode | 83 +++++++++++++++++++++++++--------------
 2 files changed, 97 insertions(+), 63 deletions(-)

-- 
2.43.0

Re: [PATCH v2 0/7] target/sparc: Relax some decode for v7/v8

Posted by Michael Tokarev 4 months, 2 weeks ago

On 05.09.2025 14:51, Richard Henderson wrote:
> Hi Mark,
> 
> I noticed a few other places where we probably want to
> allow unused bits to be set and ignored for pre-v9.
> 
> Changes for v2:
>    - Use TRANS() in the STBAR and RDY patches.
>    - Apply the same relaxation for RDPSR, RDWIM, RDTBR.
>    - Do not report illegal_instruction when unused bits
>      are set in the rs2_or_imm field.
> 
> r~
> 
> 
> Supercedes: 20250905051936.92815-1-richard.henderson@linaro.org
> 
> Richard Henderson (7):
>    target/sparc: Allow TRANS macro with no extra arguments
>    target/sparc: Loosen decode of STBAR for v8
>    target/sparc: Loosen decode of RDY for v7
>    target/sparc: Loosen decode of RDPSR for v7
>    target/sparc: Loosen decode of RDWIM for v7
>    target/sparc: Loosen decode of RDTBR for v7
>    target/sparc: Relax decode of rs2_or_imm for v7

This might also be good candidate for stable series (10.0 and 10.1
at least).  Dunno if it is worth the effort though, but the effort
is minimal so why not.

Thanks,

/mjt

Re: [PATCH v2 0/7] target/sparc: Relax some decode for v7/v8

Posted by Richard Henderson 4 months, 2 weeks ago

On 9/24/25 13:25, Michael Tokarev wrote:
> On 05.09.2025 14:51, Richard Henderson wrote:
>> Hi Mark,
>>
>> I noticed a few other places where we probably want to
>> allow unused bits to be set and ignored for pre-v9.
>>
>> Changes for v2:
>>    - Use TRANS() in the STBAR and RDY patches.
>>    - Apply the same relaxation for RDPSR, RDWIM, RDTBR.
>>    - Do not report illegal_instruction when unused bits
>>      are set in the rs2_or_imm field.
>>
>> r~
>>
>>
>> Supercedes: 20250905051936.92815-1-richard.henderson@linaro.org
>>
>> Richard Henderson (7):
>>    target/sparc: Allow TRANS macro with no extra arguments
>>    target/sparc: Loosen decode of STBAR for v8
>>    target/sparc: Loosen decode of RDY for v7
>>    target/sparc: Loosen decode of RDPSR for v7
>>    target/sparc: Loosen decode of RDWIM for v7
>>    target/sparc: Loosen decode of RDTBR for v7
>>    target/sparc: Relax decode of rs2_or_imm for v7
> 
> This might also be good candidate for stable series (10.0 and 10.1
> at least).  Dunno if it is worth the effort though, but the effort
> is minimal so why not.

Yes, since it's easy.  Especially the second patch is needed for Solaris 8.


r~