Re: Multiplexed registers and invalidating the register cache

[Andrew Cagney <cagney@gnu.org>]

> Andrew Cagney wrote:
> 
>>
>> Consider the effect of modifying the $sp.
>>
>> While it might in theory be possible to implement some sort of complicated look-aside cache schema, in reality there is zero return on investment.  Since recovery from the flush can't be slower than recovery from single-step, and single step is way way more critical, we should focus on single step.
> 
> 
> Ok, I'm convinced that the whole frame cache should be discarded, except I must be missing something since calling flush_cached_frames doesn't refetch the current set of registers (like calling registers_changed does). 

(mumble something about doco) two fyis:

- the frame cache is built on-demand, hence the absence of any explict 
rebuild call (one characteristic of a frame ID is that it survives frame 
cache flushes)
- there shouldn't be separate register and frame flush calls, combining 
the two into a single observer call is a thing-to-do-today

enjoy,
Andrew