Re: [RFA] Testing REGISTER_NAME in mips-linux-nat.c

[Andrew Cagney <ac131313@redhat.com>]

> A recent change to mips_register_name to return a empty string for
> register numbers < NUM_REGS is causing problems with the native mips
> linux port.  The change in mips_register_name is:

Arrgh, they keep turning up :-(

>   +   /* Map [NUM_REGS .. 2*NUM_REGS) onto the raw registers, but then
>   +      don't make the raw register names visible.  */
>   +   int rawnum = regno % NUM_REGS;
>   +   if (regno < NUM_REGS)
>   +     return "";
> 
> Now for example when mips_linux_cannot_fetch_register() is called with
> regno == PC_REGNUM, it will return 1 and reading of the PC will return
> zero as the PC value.
> 
> I think this is the correct patch, but I'm not 100% sure.  Perhaps we
> can just eliminate the REGISTER_NAME check completely.

The assertion:

	gdb_assert (regno >= 0 && regno < NUM_REGS);

holds so, yes, eliminating REGISTER_NAME would make sense.

Hmm, how come this doesn't just use PTRACE_GETREGS?

Daniel?

Andrew



> ============================================================================
> 
> 
> 2003-06-27  Fred Fish  <fnf@intrinsity.com>
> 
> 	* mips-linux-nat.c (mips_linux_cannot_fetch_register): Only test
> 	register name if it is a pseudo register.
>  
> 
> Index: mips-linux-nat.c
> ===================================================================
> RCS file: /mips/newtools/fsf/gdb/gdb/mips-linux-nat.c,v
> retrieving revision 1.2
> diff -c -p -r1.2 mips-linux-nat.c
> *** mips-linux-nat.c	2003/02/18 21:36:24	1.2
> --- mips-linux-nat.c	2003/06/27 17:11:38
> ***************
> *** 29,35 ****
>   int
>   mips_linux_cannot_fetch_register (int regno)
>   {
> !   if (REGISTER_NAME (regno)[0] == 0)
>       return 1;
>     if (regno == PS_REGNUM)
>       return 1;
> --- 29,35 ----
>   int
>   mips_linux_cannot_fetch_register (int regno)
>   {
> !   if (regno >= NUM_REGS && REGISTER_NAME (regno)[0] == 0)
>       return 1;
>     if (regno == PS_REGNUM)
>       return 1;
> *************** mips_linux_cannot_fetch_register (int re
> *** 42,48 ****
>   int
>   mips_linux_cannot_store_register (int regno)
>   {
> !   if (REGISTER_NAME (regno)[0] == 0)
>       return 1;
>     if (regno == PS_REGNUM)
>       return 1;
> --- 42,48 ----
>   int
>   mips_linux_cannot_store_register (int regno)
>   {
> !   if (regno >= NUM_REGS && REGISTER_NAME (regno)[0] == 0)
>       return 1;
>     if (regno == PS_REGNUM)
>       return 1;
>