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

[fnf@intrinsity.com (Fred Fish)]

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:

  +   /* 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.

-Fred

============================================================================


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;