This is the mail archive of the
gdb-patches@sources.redhat.com
mailing list for the GDB project.
Re: [PATCH] pseudo-register un-optimization
- To: Michael Snyder <msnyder at cygnus dot com>
- Subject: Re: [PATCH] pseudo-register un-optimization
- From: Andrew Cagney <ac131313 at cygnus dot com>
- Date: Fri, 10 Aug 2001 19:52:32 -0400
- Cc: gdb-patches at sources dot redhat dot com
- References: <3B7456F6.5596AE84@cygnus.com>
>
>
> 2001-08-10 Michael Snyder <msnyder@redhat.com>
>
> * regcache.c (legacy_write_register_gen): Don't 'optimize out'
> a write_register to a pseudo-reg. Target_store_pseudo_register
> needs to get called, because these regs may be computed and may
> have side-effects.
Michael, can you expand a little? This is legacy code, so as long as
this change is to keep an old target working, I'm not too fussed.
However, if this is for a new target then it should really be looking at
gdbarch_register_{read,write} and bypassing the legacy mess entirely.
Andrew
> Index: regcache.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/regcache.c,v
> retrieving revision 1.24
> diff -c -3 -p -r1.24 regcache.c
> *** regcache.c 2001/06/15 23:50:46 1.24
> --- regcache.c 2001/08/10 21:49:23
> *************** legacy_write_register_gen (int regnum, c
> *** 334,348 ****
>
> size = REGISTER_RAW_SIZE (regnum);
>
> - /* If we have a valid copy of the register, and new value == old value,
> - then don't bother doing the actual store. */
> -
> - if (register_cached (regnum)
> - && memcmp (register_buffer (regnum), myaddr, size) == 0)
> - return;
> -
> if (real_register (regnum))
> ! target_prepare_to_store ();
>
> memcpy (register_buffer (regnum), myaddr, size);
>
> --- 334,349 ----
>
> size = REGISTER_RAW_SIZE (regnum);
>
> if (real_register (regnum))
> ! {
> ! /* If we have a valid copy of the register, and new value == old
> ! value, then don't bother doing the actual store. */
> ! if (register_cached (regnum)
> ! && memcmp (register_buffer (regnum), myaddr, size) == 0)
> ! return;
> ! else
> ! target_prepare_to_store ();
> ! }
>
> memcpy (register_buffer (regnum), myaddr, size);
>
>