Re: [RFC PATCH v5 3/9] Add scoped_restore_regcache_ptid

Simon Marchi
2018-03-17T18:08:17Z

On 2018-03-12 11:31 AM, Philipp Rudo wrote:
> When a target and its target beneath use different ptids to identify a
> thread the regcaches ptid has to be set/restored when calls are passed down
> to the target beneath to e.g. fetch_registers. Add a scoped_restore to
> simplify this.

Though I don't understand yet why this is needed (I'll find out when reading
the following patches), the implementation looks ok.

I don't think this is an issue (at least for now), but there is this observer
"thread_ptid_changed" that indicates when a thread changes ptid. If this
observer is triggered while we have temporarily changed a regcache's ptid,
I guess we could miss updating a regcache's ptid, as
scoped_restore_regcache_ptid will reset it to the old ptid. It's probably
not a problem but I think it's good to be aware of this.

Simon