This is the mail archive of the
gdb-patches@sources.redhat.com
mailing list for the GDB project.
Re: PATCH ARM initial support for different floating-point models
- From: Andrew Cagney <ac131313 at cygnus dot com>
- To: Richard dot Earnshaw at arm dot com
- Cc: gdb-patches at sources dot redhat dot com
- Date: Tue, 19 Feb 2002 18:12:13 -0500
- Subject: Re: PATCH ARM initial support for different floating-point models
- References: <200202191923.TAA06815@cam-mail2.cambridge.arm.com>
Hmm, I'm afraid you may have just stepped into the
write_register_bytes() bear trap :-( Have a look at the comments in
regcache.c for the history.
> Index: arm-tdep.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/arm-tdep.c,v
> retrieving revision 1.47
> diff -p -r1.47 arm-tdep.c
> *** arm-tdep.c 2002/02/19 13:57:35 1.47
> --- arm-tdep.c 2002/02/19 19:14:40
> *************** arm_extract_return_value (struct type *t
> *** 2139,2145 ****
> char *valbuf)
> {
> if (TYPE_CODE_FLT == TYPE_CODE (type))
> ! convert_from_extended (®buf[REGISTER_BYTE (ARM_F0_REGNUM)], valbuf);
> else
> memcpy (valbuf, ®buf[REGISTER_BYTE (ARM_A1_REGNUM)],
> TYPE_LENGTH (type));
Here, unfortunatly, directly pokeing around the regcache buffer (a
parameter) is still the only way to do this.
> TYPE_LENGTH (type));
> *************** arm_store_return_value (struct type *typ
> *** 2256,2270 ****
> {
> if (TYPE_CODE (type) == TYPE_CODE_FLT)
> {
> char buf[MAX_REGISTER_RAW_SIZE];
>
> ! convert_to_extended (valbuf, buf);
> ! /* XXX Is this correct for soft-float? */
> ! write_register_bytes (REGISTER_BYTE (ARM_F0_REGNUM), buf,
> ! MAX_REGISTER_RAW_SIZE);
I think your changes to this function can be rewritten to use
write_register_gen(REGNUM,BUF).
Need to be careful though. If the code is assuming a floating point
value should be stored across multiple adjacent registers then the code
will need to be broken down into separate explicit writes.
enjoy,
Andrew