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 #include "mips-tdep.h"
  40
  41 static void fetch_core_registers (char *, unsigned int, int, CORE_ADDR);
  42
  43 /* Size of elements in jmpbuf */
  44
  45 #define JB_ELEMENT_SIZE 4
  46
  47 /*
  48  * See the comment in m68k-tdep.c regarding the utility of these functions.
  49  *
  50  * These definitions are from the MIPS SVR4 ABI, so they may work for
  51  * any MIPS SVR4 target.
  52  */
  53
  54 void
  55 supply_gregset (gregset_t *gregsetp)
  56 {
  57   int regi;
  58   greg_t *regp = &(*gregsetp)[0];
  59   int gregoff = sizeof (greg_t) - mips_regsize (current_gdbarch);
  60   static char zerobuf[32] = {0};
  61
  62   for (regi = 0; regi <= CTX_RA; regi++)
  63     supply_register (regi, (char *) (regp + regi) + gregoff);
  64
  65   supply_register (mips_regnum (current_gdbarch)->pc,
  66                    (char *) (regp + CTX_EPC) + gregoff);
  67   supply_register (mips_regnum (current_gdbarch)->hi,
  68                    (char *) (regp + CTX_MDHI) + gregoff);
  69   supply_register (mips_regnum (current_gdbarch)->lo,
  70                    (char *) (regp + CTX_MDLO) + gregoff);
  71   supply_register (mips_regnum (current_gdbarch)->cause,
  72                    (char *) (regp + CTX_CAUSE) + gregoff);
  73
  74   /* Fill inaccessible registers with zero.  */
  75   supply_register (mips_regnum (current_gdbarch)->badvaddr, zerobuf);
  76 }
  77
  78 void
  79 fill_gregset (gregset_t *gregsetp, int regno)
  80 {
  81   int regi;
  82   greg_t *regp = &(*gregsetp)[0];
  83
  84   /* Under Irix6, if GDB is built with N32 ABI and is debugging an O32
  85      executable, we have to sign extend the registers to 64 bits before
  86      filling in the gregset structure.  */
  87
  88   for (regi = 0; regi <= CTX_RA; regi++)
  89     if ((regno == -1) || (regno == regi))
  90       *(regp + regi) =
  91         extract_signed_integer (&deprecated_registers[DEPRECATED_REGISTER_BYTE (regi)],
  92                                 DEPRECATED_REGISTER_RAW_SIZE (regi));
  93
  94   if ((regno == -1) || (regno == PC_REGNUM))
  95     *(regp + CTX_EPC) =
  96       extract_signed_integer (&deprecated_registers[DEPRECATED_REGISTER_BYTE (mips_regnum (current_gdbarch)->pc)],
  97                               DEPRECATED_REGISTER_RAW_SIZE (mips_regnum (current_gdbarch)->pc));
  98
  99   if ((regno == -1) || (regno == mips_regnum (current_gdbarch)->cause))
 100     *(regp + CTX_CAUSE) =
 101       extract_signed_integer (&deprecated_registers[DEPRECATED_REGISTER_BYTE (mips_regnum (current_gdbarch)->cause)],
 102                               DEPRECATED_REGISTER_RAW_SIZE (mips_regnum (current_gdbarch)->cause));
 103
 104   if ((regno == -1)
 105       || (regno == mips_regnum (current_gdbarch)->hi))
 106     *(regp + CTX_MDHI) =
 107       extract_signed_integer (&deprecated_registers[DEPRECATED_REGISTER_BYTE (mips_regnum (current_gdbarch)->hi)],
 108                               DEPRECATED_REGISTER_RAW_SIZE (mips_regnum (current_gdbarch)->hi));
 109
 110   if ((regno == -1) || (regno == mips_regnum (current_gdbarch)->lo))
 111     *(regp + CTX_MDLO) =
 112       extract_signed_integer (&deprecated_registers[DEPRECATED_REGISTER_BYTE (mips_regnum (current_gdbarch)->lo)],
 113                               DEPRECATED_REGISTER_RAW_SIZE (mips_regnum (current_gdbarch)->lo));
 114 }
 115
 116 /*
 117  * Now we do the same thing for floating-point registers.
 118  * We don't bother to condition on FP0_REGNUM since any
 119  * reasonable MIPS configuration has an R3010 in it.
 120  *
 121  * Again, see the comments in m68k-tdep.c.
 122  */
 123
 124 void
 125 supply_fpregset (fpregset_t *fpregsetp)
 126 {
 127   int regi;
 128   static char zerobuf[32] = {0};
 129
 130   /* FIXME, this is wrong for the N32 ABI which has 64 bit FP regs. */
 131
 132   for (regi = 0; regi < 32; regi++)
 133     supply_register (FP0_REGNUM + regi,
 134                      (char *) &fpregsetp->fp_r.fp_regs[regi]);
 135
 136   supply_register (mips_regnum (current_gdbarch)->fp_control_status,
 137                    (char *) &fpregsetp->fp_csr);
 138
 139   /* FIXME: how can we supply FCRIR?  SGI doesn't tell us. */
 140   supply_register (mips_regnum (current_gdbarch)->fp_implementation_revision,
 141                    zerobuf);
 142 }
 143
 144 void
 145 fill_fpregset (fpregset_t *fpregsetp, int regno)
 146 {
 147   int regi;
 148   char *from, *to;
 149
 150   /* FIXME, this is wrong for the N32 ABI which has 64 bit FP regs. */
 151
 152   for (regi = FP0_REGNUM; regi < FP0_REGNUM + 32; regi++)
 153     {
 154       if ((regno == -1) || (regno == regi))
 155         {
 156           from = (char *) &deprecated_registers[DEPRECATED_REGISTER_BYTE (regi)];
 157           to = (char *) &(fpregsetp->fp_r.fp_regs[regi - FP0_REGNUM]);
 158           memcpy (to, from, DEPRECATED_REGISTER_RAW_SIZE (regi));
 159         }
 160     }
 161
 162   if ((regno == -1)
 163       || (regno == mips_regnum (current_gdbarch)->fp_control_status))
 164     fpregsetp->fp_csr = *(unsigned *) &deprecated_registers[DEPRECATED_REGISTER_BYTE (mips_regnum (current_gdbarch)->fp_control_status)];
 165 }
 166
 167
 168 /* Figure out where the longjmp will land.
 169    We expect the first arg to be a pointer to the jmp_buf structure from which
 170    we extract the pc (JB_PC) that we will land at.  The pc is copied into PC.
 171    This routine returns true on success. */
 172
 173 int
 174 get_longjmp_target (CORE_ADDR *pc)
 175 {
 176   char *buf;
 177   CORE_ADDR jb_addr;
 178
 179   buf = alloca (TARGET_PTR_BIT / TARGET_CHAR_BIT);
 180   jb_addr = read_register (A0_REGNUM);
 181
 182   if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf,
 183                           TARGET_PTR_BIT / TARGET_CHAR_BIT))
 184     return 0;
 185
 186   *pc = extract_unsigned_integer (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
 187
 188   return 1;
 189 }
 190
 191 /* Provide registers to GDB from a core file.
 192
 193    CORE_REG_SECT points to an array of bytes, which were obtained from
 194    a core file which BFD thinks might contain register contents.
 195    CORE_REG_SIZE is its size.
 196
 197    Normally, WHICH says which register set corelow suspects this is:
 198      0 --- the general-purpose register set
 199      2 --- the floating-point register set
 200    However, for Irix 5, WHICH isn't used.
 201
 202    REG_ADDR is also unused.  */
 203
 204 static void
 205 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
 206                       int which, CORE_ADDR reg_addr)
 207 {
 208   if (core_reg_size == DEPRECATED_REGISTER_BYTES)
 209     {
 210       memcpy ((char *) deprecated_registers, core_reg_sect, core_reg_size);
 211     }
 212   else if (mips_regsize (current_gdbarch) == 4 &&
 213            core_reg_size == (2 * mips_regsize (current_gdbarch)) * NUM_REGS)
 214     {
 215       /* This is a core file from a N32 executable, 64 bits are saved
 216          for all registers.  */
 217       char *srcp = core_reg_sect;
 218       char *dstp = deprecated_registers;
 219       int regno;
 220
 221       for (regno = 0; regno < NUM_REGS; regno++)
 222         {
 223           if (regno >= FP0_REGNUM && regno < (FP0_REGNUM + 32))
 224             {
 225               /* FIXME, this is wrong, N32 has 64 bit FP regs, but GDB
 226                  currently assumes that they are 32 bit.  */
 227               *dstp++ = *srcp++;
 228               *dstp++ = *srcp++;
 229               *dstp++ = *srcp++;
 230               *dstp++ = *srcp++;
 231               if (DEPRECATED_REGISTER_RAW_SIZE (regno) == 4)
 232                 {
 233                   /* copying 4 bytes from eight bytes?
 234                      I don't see how this can be right...  */
 235                   srcp += 4;
 236                 }
 237               else
 238                 {
 239                   /* copy all 8 bytes (sizeof(double)) */
 240                   *dstp++ = *srcp++;
 241                   *dstp++ = *srcp++;
 242                   *dstp++ = *srcp++;
 243                   *dstp++ = *srcp++;
 244                 }
 245             }
 246           else
 247             {
 248               srcp += 4;
 249               *dstp++ = *srcp++;
 250               *dstp++ = *srcp++;
 251               *dstp++ = *srcp++;
 252               *dstp++ = *srcp++;
 253             }
 254         }
 255     }
 256   else
 257     {
 258       warning ("wrong size gregset struct in core file");
 259       return;
 260     }
 261
 262   deprecated_registers_fetched ();
 263 }
 264
 265 /* Register that we are able to handle irix5 core file formats.
 266    This really is bfd_target_unknown_flavour */
 267
 268 static struct core_fns irix5_core_fns =
 269 {
 270   bfd_target_unknown_flavour,           /* core_flavour */
 271   default_check_format,                 /* check_format */
 272   default_core_sniffer,                 /* core_sniffer */
 273   fetch_core_registers,                 /* core_read_registers */
 274   NULL                                  /* next */
 275 };
 276
 277 void
 278 _initialize_core_irix5 (void)
 279 {
 280   deprecated_add_core_fns (&irix5_core_fns);
 281 }