Re: [PATCH] Replace regbuf with regcache in record-full.c

[Yao Qi <qiyaoltc@gmail.com>]

Alan Hayward <Alan.Hayward@arm.com> writes:

> Resulting in:
>   void raw_supply (int regnum, const void *buf);
>   void raw_supply (int regnum, const struct regcache *src_regcache);
                                 ^^^^^^^^^^^^^^^^^^^^^^^^
We should use reference instead of pointer, otherwise, raw_supply (0, NULL)
is ambiguous.

>> 
>> http://people.linaro.org/~yao.qi/gdb/doxy/regcache-split/gdb-xref/classregcache.html
>> 
>> Do you like this design?  One more thing is that the new class
>> regcache_collect_supply can be used in target_ops hooks
>> to_fetch_registers, to_store_registers, to_prepare_to_store,
>> 
>>    void (*to_fetch_registers) (struct target_ops *, regcache_collect_supply *, int)
>>      TARGET_DEFAULT_IGNORE ();
>>    void (*to_store_registers) (struct target_ops *, regcache_collect_supply *, int)
>>      TARGET_DEFAULT_NORETURN (noprocess ());
>>    void (*to_prepare_to_store) (struct target_ops *, regcache_collect_supply *)
>>      TARGET_DEFAULT_NORETURN (noprocess ());
>> 
>> so that all the implementations of these methods above can only access
>> raw_{collect,supply}XX methods, and they can't access
>> {raw,cooked}_{read,write}XXX methods, which in turn may call target_ops
>> to_fetch_registers and to_store_registers again.
>> 
>
> Following this through, regcache_dup and regcache_cpy should create a
> detached_regcache ?
>

Yes, it can be.

> Code would be free to write to the detached_regcache and there would
> be no need to mark
> it as “read-only”.

No.

>
> Would there be any requirement to still have a read-only regcache ?

The detached_regcache can be read-write and read-only.  regcache_dup and
regcache_cpy create the read-only one, but record-full still uses the
read-write one.

-- 
Yao (齐尧)