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Re: [rfc] frame->frame => frame->addr && frame->base()
> // High level language concept of the base address of a frame. Often
>> refered to as ``frame_base'' or ``frame pointer''. This value should
>> only be computed on-demand. It is strongly recommended, though, that
>> implementations cache the computed value in the frame cache. The method
>> is initialized as part of the frame objects creation. The default
>> method returns frame->addr. (see dwarf2 DW_AT_frame_base)
>> CORE_ADDR (*base) (struct frame_info *frame);
> This translates the CFA (canonical frame address) into an address that's
> useful for some other purpose, right? What are the purposes that it
> would be used for?
Strictly speaking it doesn't translate a CFA. The CFA is something
private to the CFI code. It is just that it happens to evaluate to the
In dwarf2, the debug info may indicate that both ->addr and ->base have
the value of [r31]+10.
> (My worry is that there may be more than one translation which might
> prove to be useful.)
The intent is for dwarf2 where a location expression can contain
references to ``fpreg''. That is really a reference to the current
value of DW_AT_frame_base. I guess the comment should emphasize how it
relates to debug info and the debug ``frame base'' register.