Re: ARM frame fp is not always FP_REGNUM

[Andrew Cagney <ac131313 at cygnus dot com>]

Alexandre Oliva wrote:
> 
> On Jul  4, 2000, Andrew Cagney <ac131313@cygnus.com> wrote:
> 
> > FP_REGNUM refers to GDB's internal frame-handle / frame-pointer /
> > frame-base variable.
> 
> On ARM, it's register 11, which is a real register.  But SP_REGNUM is
> register 13.  Then, when framereg == 13 in EXTRA_FRAME_INFO, `info
> regs' will display the value of r13 for r11, and the actual value of
> r11 cannot be obtained.

How does this compare to when you do an info registers when at the inner
most frame?

Hmm, I remember reading something about this in the doco recently. 
Check:

http://sourceware.cygnus.com/gdb/onlinedocs/gdb_9.html#SEC60
@value{GDBN} has four ``standard'' register names that are available (in
expressions) on most machines---whenever they do not conflict with an
architecture's canonical mnemonics for registers.  The register names
@code{$pc} and @code{$sp} are used for the program counter register and
the stack pointer.  @code{$fp} is used for a register that contains a
pointer to the current stack frame, and @code{$ps} is used for a
register that contains the processor status.  For example,
you could print the program counter in hex with


This suggests that providing the ``$fp'' pseudo register is wrong for
this target.

	Andrew