Re: [PATCH v5 16/17] accel/tcg: Introduce TARGET_TB_PCREL

[Peter Maydell]

On Sun, 25 Sept 2022 at 12:15, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> Prepare for targets to be able to produce TBs that can
> run in more than one virtual context.

> -/* Similarly, but for logs. */
> +/*
> + * Similarly, but for logs. In this case, when the virtual pc
> + * is not available, use the physical address.
> + */
>  static inline target_ulong tb_pc_log(const TranslationBlock *tb)
>  {
> +#if TARGET_TB_PCREL
> +    return tb->page_addr[0];
> +#else
>      return tb->pc;
> +#endif
>  }

This is going to break previously working setups involving
the "filter logging to a particular address range" and also
anybody post-processing logfiles and expecting to see
the virtual address in -d exec logging, I think.

For the exec logging, we surely must know the actual
virtual PC at the point of TB execution -- we were
previously just using tb->pc as a convenient architecture
independent place to get that from, but should now do
something else.

For places where logging a virtual PC becomes meaningless,
we should at least indicate whether we're logging a
physaddr or a vaddr, because now depending on the config
we might do either.

For the range-filter stuff, I'm not sure what to do.
Alex, any ideas?

(I see the -dfilter option documentation doesn't say
whether it's intending to work on physical or virtual
addresses...)

thanks
-- PMM