gdb/irix5-nat.c

   1 /* Native support for the SGI Iris running IRIX version 5, for GDB.
   2    Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998,
   3    1999, 2000, 2001, 2002 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    Modified for Irix 5.x by Ian Lance Taylor.
   8
   9    This file is part of GDB.
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 2 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program; if not, write to the Free Software
  23    Foundation, Inc., 59 Temple Place - Suite 330,
  24    Boston, MA 02111-1307, USA.  */
  25
  26 #include "defs.h"
  27 #include "inferior.h"
  28 #include "gdbcore.h"
  29 #include "target.h"
  30 #include "regcache.h"
  31
  32 #include "gdb_string.h"
  33 #include <sys/time.h>
  34 #include <sys/procfs.h>
  35 #include <setjmp.h>             /* For JB_XXX.  */
  36
  37 /* Prototypes for supply_gregset etc. */
  38 #include "gregset.h"
  39
  40 static void fetch_core_registers (char *, unsigned int, int, CORE_ADDR);
  41
  42 /* Size of elements in jmpbuf */
  43
  44 #define JB_ELEMENT_SIZE 4
  45
  46 /*
  47  * See the comment in m68k-tdep.c regarding the utility of these functions.
  48  *
  49  * These definitions are from the MIPS SVR4 ABI, so they may work for
  50  * any MIPS SVR4 target.
  51  */
  52
  53 void
  54 supply_gregset (gregset_t *gregsetp)
  55 {
  56   register int regi;
  57   register greg_t *regp = &(*gregsetp)[0];
  58   int gregoff = sizeof (greg_t) - MIPS_REGSIZE;
  59   static char zerobuf[32] = {0};
  60
  61   for (regi = 0; regi <= CTX_RA; regi++)
  62     supply_register (regi, (char *) (regp + regi) + gregoff);
  63
  64   supply_register (PC_REGNUM, (char *) (regp + CTX_EPC) + gregoff);
  65   supply_register (HI_REGNUM, (char *) (regp + CTX_MDHI) + gregoff);
  66   supply_register (LO_REGNUM, (char *) (regp + CTX_MDLO) + gregoff);
  67   supply_register (CAUSE_REGNUM, (char *) (regp + CTX_CAUSE) + gregoff);
  68
  69   /* Fill inaccessible registers with zero.  */
  70   supply_register (BADVADDR_REGNUM, zerobuf);
  71 }
  72
  73 void
  74 fill_gregset (gregset_t *gregsetp, int regno)
  75 {
  76   int regi;
  77   register greg_t *regp = &(*gregsetp)[0];
  78
  79   /* Under Irix6, if GDB is built with N32 ABI and is debugging an O32
  80      executable, we have to sign extend the registers to 64 bits before
  81      filling in the gregset structure.  */
  82
  83   for (regi = 0; regi <= CTX_RA; regi++)
  84     if ((regno == -1) || (regno == regi))
  85       *(regp + regi) =
  86         extract_signed_integer (&deprecated_registers[REGISTER_BYTE (regi)],
  87                                 REGISTER_RAW_SIZE (regi));
  88
  89   if ((regno == -1) || (regno == PC_REGNUM))
  90     *(regp + CTX_EPC) =
  91       extract_signed_integer (&deprecated_registers[REGISTER_BYTE (PC_REGNUM)],
  92                               REGISTER_RAW_SIZE (PC_REGNUM));
  93
  94   if ((regno == -1) || (regno == CAUSE_REGNUM))
  95     *(regp + CTX_CAUSE) =
  96       extract_signed_integer (&deprecated_registers[REGISTER_BYTE (CAUSE_REGNUM)],
  97                               REGISTER_RAW_SIZE (CAUSE_REGNUM));
  98
  99   if ((regno == -1) || (regno == HI_REGNUM))
 100     *(regp + CTX_MDHI) =
 101       extract_signed_integer (&deprecated_registers[REGISTER_BYTE (HI_REGNUM)],
 102                               REGISTER_RAW_SIZE (HI_REGNUM));
 103
 104   if ((regno == -1) || (regno == LO_REGNUM))
 105     *(regp + CTX_MDLO) =
 106       extract_signed_integer (&deprecated_registers[REGISTER_BYTE (LO_REGNUM)],
 107                               REGISTER_RAW_SIZE (LO_REGNUM));
 108 }
 109
 110 /*
 111  * Now we do the same thing for floating-point registers.
 112  * We don't bother to condition on FP0_REGNUM since any
 113  * reasonable MIPS configuration has an R3010 in it.
 114  *
 115  * Again, see the comments in m68k-tdep.c.
 116  */
 117
 118 void
 119 supply_fpregset (fpregset_t *fpregsetp)
 120 {
 121   register int regi;
 122   static char zerobuf[32] = {0};
 123
 124   /* FIXME, this is wrong for the N32 ABI which has 64 bit FP regs. */
 125
 126   for (regi = 0; regi < 32; regi++)
 127     supply_register (FP0_REGNUM + regi,
 128                      (char *) &fpregsetp->fp_r.fp_regs[regi]);
 129
 130   supply_register (FCRCS_REGNUM, (char *) &fpregsetp->fp_csr);
 131
 132   /* FIXME: how can we supply FCRIR_REGNUM?  SGI doesn't tell us. */
 133   supply_register (FCRIR_REGNUM, zerobuf);
 134 }
 135
 136 void
 137 fill_fpregset (fpregset_t *fpregsetp, int regno)
 138 {
 139   int regi;
 140   char *from, *to;
 141
 142   /* FIXME, this is wrong for the N32 ABI which has 64 bit FP regs. */
 143
 144   for (regi = FP0_REGNUM; regi < FP0_REGNUM + 32; regi++)
 145     {
 146       if ((regno == -1) || (regno == regi))
 147         {
 148           from = (char *) &deprecated_registers[REGISTER_BYTE (regi)];
 149           to = (char *) &(fpregsetp->fp_r.fp_regs[regi - FP0_REGNUM]);
 150           memcpy (to, from, REGISTER_RAW_SIZE (regi));
 151         }
 152     }
 153
 154   if ((regno == -1) || (regno == FCRCS_REGNUM))
 155     fpregsetp->fp_csr = *(unsigned *) &deprecated_registers[REGISTER_BYTE (FCRCS_REGNUM)];
 156 }
 157
 158
 159 /* Figure out where the longjmp will land.
 160    We expect the first arg to be a pointer to the jmp_buf structure from which
 161    we extract the pc (JB_PC) that we will land at.  The pc is copied into PC.
 162    This routine returns true on success. */
 163
 164 int
 165 get_longjmp_target (CORE_ADDR *pc)
 166 {
 167   char *buf;
 168   CORE_ADDR jb_addr;
 169
 170   buf = alloca (TARGET_PTR_BIT / TARGET_CHAR_BIT);
 171   jb_addr = read_register (A0_REGNUM);
 172
 173   if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf,
 174                           TARGET_PTR_BIT / TARGET_CHAR_BIT))
 175     return 0;
 176
 177   *pc = extract_unsigned_integer (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
 178
 179   return 1;
 180 }
 181
 182 /* Provide registers to GDB from a core file.
 183
 184    CORE_REG_SECT points to an array of bytes, which were obtained from
 185    a core file which BFD thinks might contain register contents.
 186    CORE_REG_SIZE is its size.
 187
 188    Normally, WHICH says which register set corelow suspects this is:
 189      0 --- the general-purpose register set
 190      2 --- the floating-point register set
 191    However, for Irix 5, WHICH isn't used.
 192
 193    REG_ADDR is also unused.  */
 194
 195 static void
 196 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
 197                       int which, CORE_ADDR reg_addr)
 198 {
 199   if (core_reg_size == DEPRECATED_REGISTER_BYTES)
 200     {
 201       memcpy ((char *) deprecated_registers, core_reg_sect, core_reg_size);
 202     }
 203   else if (MIPS_REGSIZE == 4 &&
 204            core_reg_size == (2 * MIPS_REGSIZE) * NUM_REGS)
 205     {
 206       /* This is a core file from a N32 executable, 64 bits are saved
 207          for all registers.  */
 208       char *srcp = core_reg_sect;
 209       char *dstp = deprecated_registers;
 210       int regno;
 211
 212       for (regno = 0; regno < NUM_REGS; regno++)
 213         {
 214           if (regno >= FP0_REGNUM && regno < (FP0_REGNUM + 32))
 215             {
 216               /* FIXME, this is wrong, N32 has 64 bit FP regs, but GDB
 217                  currently assumes that they are 32 bit.  */
 218               *dstp++ = *srcp++;
 219               *dstp++ = *srcp++;
 220               *dstp++ = *srcp++;
 221               *dstp++ = *srcp++;
 222               if (REGISTER_RAW_SIZE (regno) == 4)
 223                 {
 224                   /* copying 4 bytes from eight bytes?
 225                      I don't see how this can be right...  */
 226                   srcp += 4;
 227                 }
 228               else
 229                 {
 230                   /* copy all 8 bytes (sizeof(double)) */
 231                   *dstp++ = *srcp++;
 232                   *dstp++ = *srcp++;
 233                   *dstp++ = *srcp++;
 234                   *dstp++ = *srcp++;
 235                 }
 236             }
 237           else
 238             {
 239               srcp += 4;
 240               *dstp++ = *srcp++;
 241               *dstp++ = *srcp++;
 242               *dstp++ = *srcp++;
 243               *dstp++ = *srcp++;
 244             }
 245         }
 246     }
 247   else
 248     {
 249       warning ("wrong size gregset struct in core file");
 250       return;
 251     }
 252
 253   deprecated_registers_fetched ();
 254 }
 255
 256 /* Register that we are able to handle irix5 core file formats.
 257    This really is bfd_target_unknown_flavour */
 258
 259 static struct core_fns irix5_core_fns =
 260 {
 261   bfd_target_unknown_flavour,           /* core_flavour */
 262   default_check_format,                 /* check_format */
 263   default_core_sniffer,                 /* core_sniffer */
 264   fetch_core_registers,                 /* core_read_registers */
 265   NULL                                  /* next */
 266 };
 267
 268 void
 269 _initialize_core_irix5 (void)
 270 {
 271   add_core_fns (&irix5_core_fns);
 272 }