On 19.09.2012, at 13:29, Peter Maydell wrote:
> On 19 September 2012 01:14, Richard Henderson <r...@twiddle.net> wrote:
>> On 09/18/2012 01:18 PM, Alexander Graf wrote:
>>>> - /* remember what pgm exeption this was */
>>>> + /* Remember what pgm exeption this was. */
>
> ...if you're changing this comment then at least fix the typo
> ("exception")...
>
>>>> tmp = tcg_const_i32(code);
>>>> tcg_gen_st_i32(tmp, cpu_env, offsetof(CPUS390XState, int_pgm_code));
>>>> tcg_temp_free_i32(tmp);
>>>> - tmp = tcg_const_i32(ilc);
>>>> + tmp = tcg_const_i32(s->next_pc - s->pc);
>>>
>>> Mind to explain this one?
>>
>> ILC = the size of the insn. Rather than passing ILC around into
>> gen_program_exception, get it back from the s->next_pc value that
>> we stored into DisasContext.
>
> ...but isn't (s-next_pc - s->pc) ilc*2, not ilc? Compare this hunk
> from elsewhere in the patch:
>
> - tmp32_2 = tcg_const_i32(ilc * 2);
> - tmp32_3 = tcg_const_i32(EXCP_SVC);
> + tmp32_2 = tcg_const_i32(s->next_pc - s->pc);
Yes, it is, and hence it's correct. The exception field encodes the real
instruction length, not the ILC bits in the opcode. Maybe the naming is
unfortunate...
Alex
