Re: [PATCH 06/10] accel/tcg: Remove cpu_unwind_state_data() unused CPUState argument

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

+Pierrick & Anton

On 15/11/24 18:33, Peter Maydell wrote:
> On Fri, 15 Nov 2024 at 17:24, Richard Henderson
> <richard.henderson@linaro.org> wrote:
>>
>> On 11/15/24 07:20, Philippe Mathieu-Daudé wrote:
>>> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
>>> ---
>>>    include/exec/translate-all.h | 3 +--
>>>    accel/tcg/translate-all.c    | 2 +-
>>>    target/i386/helper.c         | 3 ++-
>>>    target/openrisc/sys_helper.c | 7 +++----
>>>    4 files changed, 7 insertions(+), 8 deletions(-)
>>>
>>> diff --git a/include/exec/translate-all.h b/include/exec/translate-all.h
>>> index f06cfedd52..9303318953 100644
>>> --- a/include/exec/translate-all.h
>>> +++ b/include/exec/translate-all.h
>>> @@ -23,7 +23,6 @@
>>>
>>>    /**
>>>     * cpu_unwind_state_data:
>>> - * @cpu: the cpu context
>>>     * @host_pc: the host pc within the translation
>>>     * @data: output data
>>>     *
>>> @@ -32,7 +31,7 @@
>>>     * function returns false; otherwise @data is loaded.
>>>     * This is the same unwind info as given to restore_state_to_opc.
>>>     */
>>> -bool cpu_unwind_state_data(CPUState *cpu, uintptr_t host_pc, uint64_t *data);
>>> +bool cpu_unwind_state_data(uintptr_t host_pc, uint64_t *data);
>>
>> Hmm.  I wonder if it should be called "cpu_*" at all then?
>> Worth renaming to "tcg_*" or something?
> 
> Yes, it's odd, isn't it?
> 
> What's the plan for this function in a multi-target
> emulation world? At the moment it (or functions it
> calls) uses TARGET_INSN_START_WORDS which is a
> target-CPU-type-specific value. If in the future we're
> going to want it instead to look that up as e.g. some
> property of the CPU class then maybe we should keep
> passing it the CPU pointer? Or would we instead say
> that we'll define TARGET_INSN_START_WORDS as the worst
> case for any target, since it's always between 1 and 3,
> so it doesn't waste that much space if we have a couple
> of extra sleb128 zero values for targets that don't need
> all 3 words?
> 
> thanks
> -- PMM