Re: fix "too much information" bug w/ "info vector" on PowerPC

[Paul Gilliam <pgilliam at us dot ibm dot com>]

On Tuesday 30 August 2005 14:42, Jim Blandy wrote:
> - Could you also add comments above the definitions of
>   tdep->ppc_vr0_regnum and tdep->ppc_ev0_regnum in ppc-tdep.h?
>   Perhaps such comments could have prevented the bugs's appearance in
>   the first place.

Here is the new patch with comments added/chanded in ppc-tdep.h

If I hear no objections, I'll commit this tomorrow.

-=# Paul #=-

2005-08-30  Paul Gilliam <pgilliam@us.ibm.com>

        * ppc-tdep.h: better explanation of using -1 for nonexistant registers
        * rs6000-tdep.c (rs6000_register_reggroup_p): don't assume that
        tdep->ppc_vr0_regnum or tdep->ppc_ev0_regnum are not -1

Index: ppc-tdep.h
===================================================================
RCS file: /cvs/src/src/gdb/ppc-tdep.h,v
retrieving revision 1.46
diff -c -3 -p -r1.46 ppc-tdep.h
*** ppc-tdep.h  25 May 2005 03:12:13 -0000      1.46
--- ppc-tdep.h  31 Aug 2005 20:06:35 -0000
*************** struct gdbarch_tdep
*** 152,177 ****
      int ppc_ctr_regnum;               /* Count register */
      int ppc_xer_regnum;               /* Integer exception register */

!     /* On PPC and RS6000 variants that have no floating-point
!        registers, the next two members will be -1.  */
      int ppc_fp0_regnum;         /* floating-point register 0 */
!     int ppc_fpscr_regnum;     /* Floating point status and condition
!                                  register */

!     int ppc_sr0_regnum;         /* segment register 0, or -1 on
!                                    variants that have no segment
!                                    registers.  */

      int ppc_mq_regnum;                /* Multiply/Divide extension register */
      int ppc_vr0_regnum;               /* First AltiVec register */
      int ppc_vrsave_regnum;    /* Last AltiVec register */
      int ppc_ev0_upper_regnum;   /* First GPR upper half register */
      int ppc_ev0_regnum;         /* First ev register */
      int ppc_ev31_regnum;        /* Last ev register */
      int ppc_acc_regnum;         /* SPE 'acc' register */
      int ppc_spefscr_regnum;     /* SPE 'spefscr' register */
!     int lr_frame_offset;      /* Offset to ABI specific location where
!                                    link register is saved.  */

      /* An array of integers, such that sim_regno[I] is the simulator
         register number for GDB register number I, or -1 if the
--- 152,184 ----
      int ppc_ctr_regnum;               /* Count register */
      int ppc_xer_regnum;               /* Integer exception register */

!     /* Not all PPC and RS6000 variants will have the registers
!        represented below.  A -1 is used to indicate that the register
!        is not present in this variant. */
!
!     /* Floating-point registers. */
      int ppc_fp0_regnum;         /* floating-point register 0 */
!     int ppc_fpscr_regnum;     /* fp status and condition register */

!     /* Segment registers */
!     int ppc_sr0_regnum;         /* segment register 0 */

+     /* Used in some older Power architectures. */
      int ppc_mq_regnum;                /* Multiply/Divide extension register */
+
+     /* Altivec registers */
      int ppc_vr0_regnum;               /* First AltiVec register */
      int ppc_vrsave_regnum;    /* Last AltiVec register */
      int ppc_ev0_upper_regnum;   /* First GPR upper half register */
+
+     /* SPE registers. */
      int ppc_ev0_regnum;         /* First ev register */
      int ppc_ev31_regnum;        /* Last ev register */
      int ppc_acc_regnum;         /* SPE 'acc' register */
      int ppc_spefscr_regnum;     /* SPE 'spefscr' register */
!
!     /* Offset to ABI specific location where link register is saved.  */
!     int lr_frame_offset;

      /* An array of integers, such that sim_regno[I] is the simulator
         register number for GDB register number I, or -1 if the
Index: rs6000-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/rs6000-tdep.c,v
retrieving revision 1.241
diff -c -3 -p -r1.241 rs6000-tdep.c
*** rs6000-tdep.c       25 May 2005 03:12:13 -0000      1.241
--- rs6000-tdep.c       31 Aug 2005 20:06:35 -0000
*************** rs6000_register_reggroup_p (struct gdbar
*** 1882,1890 ****
    if (group == float_reggroup)
      return float_p;

!   vector_p = ((regnum >= tdep->ppc_vr0_regnum
               && regnum < tdep->ppc_vr0_regnum + 32)
!             || (regnum >= tdep->ppc_ev0_regnum
                  && regnum < tdep->ppc_ev0_regnum + 32)
              || regnum == tdep->ppc_vrsave_regnum
              || regnum == tdep->ppc_acc_regnum
--- 1882,1892 ----
    if (group == float_reggroup)
      return float_p;

!   vector_p = ((tdep->ppc_vr0_regnum >= 0
!                && regnum >= tdep->ppc_vr0_regnum
               && regnum < tdep->ppc_vr0_regnum + 32)
!             || (tdep->ppc_ev0_regnum >= 0
!                   && regnum >= tdep->ppc_ev0_regnum
                  && regnum < tdep->ppc_ev0_regnum + 32)
              || regnum == tdep->ppc_vrsave_regnum
              || regnum == tdep->ppc_acc_regnum