gdb/irix4-nat.c

   1 /* Native support for the SGI Iris running IRIX version 4, for GDB.
   2    Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1995
   3    Free Software Foundation, Inc.
   4    Contributed by Alessandro Forin(af@cs.cmu.edu) at CMU
   5    and by Per Bothner(bothner@cs.wisc.edu) at U.Wisconsin.
   6    Implemented for Irix 4.x by Garrett A. Wollman.
   7
   8    This file is part of GDB.
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 2 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 59 Temple Place - Suite 330,
  23    Boston, MA 02111-1307, USA.  */
  24
  25 #include "defs.h"
  26 #include "inferior.h"
  27 #include "gdbcore.h"
  28
  29 #include <sys/time.h>
  30 #include <sys/procfs.h>
  31 #include <setjmp.h>             /* For JB_XXX.  */
  32
  33 /* Prototypes for supply_gregset etc. */
  34 #include "gregset.h"
  35
  36 /* Size of elements in jmpbuf */
  37
  38 #define JB_ELEMENT_SIZE 4
  39
  40 typedef unsigned int greg_t;    /* why isn't this defined? */
  41
  42 static void fetch_core_registers (char *, unsigned int, int, CORE_ADDR);
  43
  44 /*
  45  * See the comment in m68k-tdep.c regarding the utility of these functions.
  46  */
  47
  48 void
  49 supply_gregset (gregset_t *gregsetp)
  50 {
  51   register int regi;
  52   register greg_t *regp = (greg_t *) (gregsetp->gp_regs);
  53   static char zerobuf[MAX_REGISTER_RAW_SIZE] =
  54   {0};
  55
  56   /* FIXME: somewhere, there should be a #define for the meaning
  57      of this magic number 32; we should use that. */
  58   for (regi = 0; regi < 32; regi++)
  59     supply_register (regi, (char *) (regp + regi));
  60
  61   supply_register (PC_REGNUM, (char *) &(gregsetp->gp_pc));
  62   supply_register (HI_REGNUM, (char *) &(gregsetp->gp_mdhi));
  63   supply_register (LO_REGNUM, (char *) &(gregsetp->gp_mdlo));
  64   supply_register (CAUSE_REGNUM, (char *) &(gregsetp->gp_cause));
  65
  66   /* Fill inaccessible registers with zero.  */
  67   supply_register (BADVADDR_REGNUM, zerobuf);
  68 }
  69
  70 void
  71 fill_gregset (gregset_t *gregsetp, int regno)
  72 {
  73   int regi;
  74   register greg_t *regp = (greg_t *) (gregsetp->gp_regs);
  75
  76   /* same FIXME as above wrt 32 */
  77   for (regi = 0; regi < 32; regi++)
  78     if ((regno == -1) || (regno == regi))
  79       *(regp + regi) = *(greg_t *) & registers[REGISTER_BYTE (regi)];
  80
  81   if ((regno == -1) || (regno == PC_REGNUM))
  82     gregsetp->gp_pc = *(greg_t *) & registers[REGISTER_BYTE (PC_REGNUM)];
  83
  84   if ((regno == -1) || (regno == CAUSE_REGNUM))
  85     gregsetp->gp_cause = *(greg_t *) & registers[REGISTER_BYTE (CAUSE_REGNUM)];
  86
  87   if ((regno == -1) || (regno == HI_REGNUM))
  88     gregsetp->gp_mdhi = *(greg_t *) & registers[REGISTER_BYTE (HI_REGNUM)];
  89
  90   if ((regno == -1) || (regno == LO_REGNUM))
  91     gregsetp->gp_mdlo = *(greg_t *) & registers[REGISTER_BYTE (LO_REGNUM)];
  92 }
  93
  94 /*
  95  * Now we do the same thing for floating-point registers.
  96  * We don't bother to condition on FP0_REGNUM since any
  97  * reasonable MIPS configuration has an R3010 in it.
  98  *
  99  * Again, see the comments in m68k-tdep.c.
 100  */
 101
 102 void
 103 supply_fpregset (fpregset_t *fpregsetp)
 104 {
 105   register int regi;
 106   static char zerobuf[MAX_REGISTER_RAW_SIZE] =
 107   {0};
 108
 109   for (regi = 0; regi < 32; regi++)
 110     supply_register (FP0_REGNUM + regi,
 111                      (char *) &fpregsetp->fp_r.fp_regs[regi]);
 112
 113   supply_register (FCRCS_REGNUM, (char *) &fpregsetp->fp_csr);
 114
 115   /* FIXME: how can we supply FCRIR_REGNUM?  SGI doesn't tell us. */
 116   supply_register (FCRIR_REGNUM, zerobuf);
 117 }
 118
 119 void
 120 fill_fpregset (fpregset_t *fpregsetp, int regno)
 121 {
 122   int regi;
 123   char *from, *to;
 124
 125   for (regi = FP0_REGNUM; regi < FP0_REGNUM + 32; regi++)
 126     {
 127       if ((regno == -1) || (regno == regi))
 128         {
 129           from = (char *) &registers[REGISTER_BYTE (regi)];
 130           to = (char *) &(fpregsetp->fp_r.fp_regs[regi - FP0_REGNUM]);
 131           memcpy (to, from, REGISTER_RAW_SIZE (regi));
 132         }
 133     }
 134
 135   if ((regno == -1) || (regno == FCRCS_REGNUM))
 136     fpregsetp->fp_csr = *(unsigned *) &registers[REGISTER_BYTE (FCRCS_REGNUM)];
 137 }
 138
 139
 140 /* Figure out where the longjmp will land.
 141    We expect the first arg to be a pointer to the jmp_buf structure from which
 142    we extract the pc (JB_PC) that we will land at.  The pc is copied into PC.
 143    This routine returns true on success. */
 144
 145 int
 146 get_longjmp_target (CORE_ADDR *pc)
 147 {
 148   char *buf;
 149   CORE_ADDR jb_addr;
 150
 151   buf = alloca (TARGET_PTR_BIT / TARGET_CHAR_BIT);
 152   jb_addr = read_register (A0_REGNUM);
 153
 154   if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf,
 155                           TARGET_PTR_BIT / TARGET_CHAR_BIT))
 156     return 0;
 157
 158   *pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
 159
 160   return 1;
 161 }
 162
 163 /* Provide registers to GDB from a core file.
 164
 165    CORE_REG_SECT points to an array of bytes, which were obtained from
 166    a core file which BFD thinks might contain register contents.
 167    CORE_REG_SIZE is its size.
 168
 169    Normally, WHICH says which register set corelow suspects this is:
 170      0 --- the general-purpose register set
 171      2 --- the floating-point register set
 172    However, for Irix 4, WHICH isn't used.
 173
 174    REG_ADDR is also unused.  */
 175
 176 static void
 177 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
 178                       int which, CORE_ADDR reg_addr)
 179 {
 180   if (core_reg_size != REGISTER_BYTES)
 181     {
 182       warning ("wrong size gregset struct in core file");
 183       return;
 184     }
 185
 186   memcpy ((char *) registers, core_reg_sect, core_reg_size);
 187 }
 188 \f
 189
 190 /* Register that we are able to handle irix4 core file formats.
 191    FIXME: is this really bfd_target_unknown_flavour? */
 192
 193 static struct core_fns irix4_core_fns =
 194 {
 195   bfd_target_unknown_flavour,           /* core_flavour */
 196   default_check_format,                 /* check_format */
 197   default_core_sniffer,                 /* core_sniffer */
 198   fetch_core_registers,                 /* core_read_registers */
 199   NULL                                  /* next */
 200 };
 201
 202 void
 203 _initialize_core_irix4 (void)
 204 {
 205   add_core_fns (&irix4_core_fns);
 206 }