gdb/sparc-nat.c

   1 /* Functions specific to running gdb native on a SPARC running SunOS4.
   2    Copyright 1989, 1992, 1993, 1994, 1996, 2001 Free Software
   3    Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "inferior.h"
  24 #include "target.h"
  25 #include "gdbcore.h"
  26 #include "regcache.h"
  27
  28 #include <signal.h>
  29 #include <sys/ptrace.h>
  30 #include <sys/wait.h>
  31 #ifdef __linux__
  32 #include <asm/reg.h>
  33 #else
  34 #include <machine/reg.h>
  35 #endif
  36 #include <sys/user.h>
  37
  38 /* We don't store all registers immediately when requested, since they
  39    get sent over in large chunks anyway.  Instead, we accumulate most
  40    of the changes and send them over once.  "deferred_stores" keeps
  41    track of which sets of registers we have locally-changed copies of,
  42    so we only need send the groups that have changed.  */
  43
  44 #define INT_REGS        1
  45 #define STACK_REGS      2
  46 #define FP_REGS         4
  47
  48 static void fetch_core_registers (char *, unsigned int, int, CORE_ADDR);
  49
  50 /* Fetch one or more registers from the inferior.  REGNO == -1 to get
  51    them all.  We actually fetch more than requested, when convenient,
  52    marking them as valid so we won't fetch them again.  */
  53
  54 void
  55 fetch_inferior_registers (int regno)
  56 {
  57   struct regs inferior_registers;
  58   struct fp_status inferior_fp_registers;
  59   int i;
  60
  61   /* We should never be called with deferred stores, because a prerequisite
  62      for writing regs is to have fetched them all (PREPARE_TO_STORE), sigh.  */
  63   if (deferred_stores)
  64     internal_error (__FILE__, __LINE__, "failed internal consistency check");
  65
  66   DO_DEFERRED_STORES;
  67
  68   /* Global and Out regs are fetched directly, as well as the control
  69      registers.  If we're getting one of the in or local regs,
  70      and the stack pointer has not yet been fetched,
  71      we have to do that first, since they're found in memory relative
  72      to the stack pointer.  */
  73   if (regno < O7_REGNUM         /* including -1 */
  74       || regno >= Y_REGNUM
  75       || (!register_valid[SP_REGNUM] && regno < I7_REGNUM))
  76     {
  77       if (0 != ptrace (PTRACE_GETREGS, inferior_pid,
  78                        (PTRACE_ARG3_TYPE) & inferior_registers, 0))
  79         perror ("ptrace_getregs");
  80
  81       registers[REGISTER_BYTE (0)] = 0;
  82       memcpy (&registers[REGISTER_BYTE (1)], &inferior_registers.r_g1,
  83               15 * REGISTER_RAW_SIZE (G0_REGNUM));
  84       *(int *) &registers[REGISTER_BYTE (PS_REGNUM)] = inferior_registers.r_ps;
  85       *(int *) &registers[REGISTER_BYTE (PC_REGNUM)] = inferior_registers.r_pc;
  86       *(int *) &registers[REGISTER_BYTE (NPC_REGNUM)] = inferior_registers.r_npc;
  87       *(int *) &registers[REGISTER_BYTE (Y_REGNUM)] = inferior_registers.r_y;
  88
  89       for (i = G0_REGNUM; i <= O7_REGNUM; i++)
  90         register_valid[i] = 1;
  91       register_valid[Y_REGNUM] = 1;
  92       register_valid[PS_REGNUM] = 1;
  93       register_valid[PC_REGNUM] = 1;
  94       register_valid[NPC_REGNUM] = 1;
  95       /* If we don't set these valid, read_register_bytes() rereads
  96          all the regs every time it is called!  FIXME.  */
  97       register_valid[WIM_REGNUM] = 1;   /* Not true yet, FIXME */
  98       register_valid[TBR_REGNUM] = 1;   /* Not true yet, FIXME */
  99       register_valid[CPS_REGNUM] = 1;   /* Not true yet, FIXME */
 100     }
 101
 102   /* Floating point registers */
 103   if (regno == -1 ||
 104       regno == FPS_REGNUM ||
 105       (regno >= FP0_REGNUM && regno <= FP0_REGNUM + 31))
 106     {
 107       if (0 != ptrace (PTRACE_GETFPREGS, inferior_pid,
 108                        (PTRACE_ARG3_TYPE) & inferior_fp_registers,
 109                        0))
 110         perror ("ptrace_getfpregs");
 111       memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)], &inferior_fp_registers,
 112               sizeof inferior_fp_registers.fpu_fr);
 113       memcpy (&registers[REGISTER_BYTE (FPS_REGNUM)],
 114               &inferior_fp_registers.Fpu_fsr,
 115               sizeof (FPU_FSR_TYPE));
 116       for (i = FP0_REGNUM; i <= FP0_REGNUM + 31; i++)
 117         register_valid[i] = 1;
 118       register_valid[FPS_REGNUM] = 1;
 119     }
 120
 121   /* These regs are saved on the stack by the kernel.  Only read them
 122      all (16 ptrace calls!) if we really need them.  */
 123   if (regno == -1)
 124     {
 125       target_read_memory (*(CORE_ADDR *) & registers[REGISTER_BYTE (SP_REGNUM)],
 126                           &registers[REGISTER_BYTE (L0_REGNUM)],
 127                           16 * REGISTER_RAW_SIZE (L0_REGNUM));
 128       for (i = L0_REGNUM; i <= I7_REGNUM; i++)
 129         register_valid[i] = 1;
 130     }
 131   else if (regno >= L0_REGNUM && regno <= I7_REGNUM)
 132     {
 133       CORE_ADDR sp = *(CORE_ADDR *) & registers[REGISTER_BYTE (SP_REGNUM)];
 134       i = REGISTER_BYTE (regno);
 135       if (register_valid[regno])
 136         printf_unfiltered ("register %d valid and read\n", regno);
 137       target_read_memory (sp + i - REGISTER_BYTE (L0_REGNUM),
 138                           &registers[i], REGISTER_RAW_SIZE (regno));
 139       register_valid[regno] = 1;
 140     }
 141 }
 142
 143 /* Store our register values back into the inferior.
 144    If REGNO is -1, do this for all registers.
 145    Otherwise, REGNO specifies which register (so we can save time).  */
 146
 147 void
 148 store_inferior_registers (int regno)
 149 {
 150   struct regs inferior_registers;
 151   struct fp_status inferior_fp_registers;
 152   int wanna_store = INT_REGS + STACK_REGS + FP_REGS;
 153
 154   /* First decide which pieces of machine-state we need to modify.
 155      Default for regno == -1 case is all pieces.  */
 156   if (regno >= 0)
 157     if (FP0_REGNUM <= regno && regno < FP0_REGNUM + 32)
 158       {
 159         wanna_store = FP_REGS;
 160       }
 161     else
 162       {
 163         if (regno == SP_REGNUM)
 164           wanna_store = INT_REGS + STACK_REGS;
 165         else if (regno < L0_REGNUM || regno > I7_REGNUM)
 166           wanna_store = INT_REGS;
 167         else if (regno == FPS_REGNUM)
 168           wanna_store = FP_REGS;
 169         else
 170           wanna_store = STACK_REGS;
 171       }
 172
 173   /* See if we're forcing the stores to happen now, or deferring. */
 174   if (regno == -2)
 175     {
 176       wanna_store = deferred_stores;
 177       deferred_stores = 0;
 178     }
 179   else
 180     {
 181       if (wanna_store == STACK_REGS)
 182         {
 183           /* Fall through and just store one stack reg.  If we deferred
 184              it, we'd have to store them all, or remember more info.  */
 185         }
 186       else
 187         {
 188           deferred_stores |= wanna_store;
 189           return;
 190         }
 191     }
 192
 193   if (wanna_store & STACK_REGS)
 194     {
 195       CORE_ADDR sp = *(CORE_ADDR *) & registers[REGISTER_BYTE (SP_REGNUM)];
 196
 197       if (regno < 0 || regno == SP_REGNUM)
 198         {
 199           if (!register_valid[L0_REGNUM + 5])
 200             internal_error (__FILE__, __LINE__, "failed internal consistency check");
 201           target_write_memory (sp,
 202                                &registers[REGISTER_BYTE (L0_REGNUM)],
 203                                16 * REGISTER_RAW_SIZE (L0_REGNUM));
 204         }
 205       else
 206         {
 207           if (!register_valid[regno])
 208             internal_error (__FILE__, __LINE__, "failed internal consistency check");
 209           target_write_memory (sp + REGISTER_BYTE (regno) - REGISTER_BYTE (L0_REGNUM),
 210                                &registers[REGISTER_BYTE (regno)],
 211                                REGISTER_RAW_SIZE (regno));
 212         }
 213
 214     }
 215
 216   if (wanna_store & INT_REGS)
 217     {
 218       if (!register_valid[G1_REGNUM])
 219         internal_error (__FILE__, __LINE__, "failed internal consistency check");
 220
 221       memcpy (&inferior_registers.r_g1, &registers[REGISTER_BYTE (G1_REGNUM)],
 222               15 * REGISTER_RAW_SIZE (G1_REGNUM));
 223
 224       inferior_registers.r_ps =
 225         *(int *) &registers[REGISTER_BYTE (PS_REGNUM)];
 226       inferior_registers.r_pc =
 227         *(int *) &registers[REGISTER_BYTE (PC_REGNUM)];
 228       inferior_registers.r_npc =
 229         *(int *) &registers[REGISTER_BYTE (NPC_REGNUM)];
 230       inferior_registers.r_y =
 231         *(int *) &registers[REGISTER_BYTE (Y_REGNUM)];
 232
 233       if (0 != ptrace (PTRACE_SETREGS, inferior_pid,
 234                        (PTRACE_ARG3_TYPE) & inferior_registers, 0))
 235         perror ("ptrace_setregs");
 236     }
 237
 238   if (wanna_store & FP_REGS)
 239     {
 240       if (!register_valid[FP0_REGNUM + 9])
 241         internal_error (__FILE__, __LINE__, "failed internal consistency check");
 242       memcpy (&inferior_fp_registers, &registers[REGISTER_BYTE (FP0_REGNUM)],
 243               sizeof inferior_fp_registers.fpu_fr);
 244       memcpy (&inferior_fp_registers.Fpu_fsr,
 245               &registers[REGISTER_BYTE (FPS_REGNUM)], sizeof (FPU_FSR_TYPE));
 246       if (0 !=
 247           ptrace (PTRACE_SETFPREGS, inferior_pid,
 248                   (PTRACE_ARG3_TYPE) & inferior_fp_registers, 0))
 249         perror ("ptrace_setfpregs");
 250     }
 251 }
 252
 253 /* Provide registers to GDB from a core file.
 254
 255    CORE_REG_SECT points to an array of bytes, which are the contents
 256    of a `note' from a core file which BFD thinks might contain
 257    register contents.  CORE_REG_SIZE is its size.
 258
 259    WHICH says which register set corelow suspects this is:
 260      0 --- the general-purpose register set
 261      2 --- the floating-point register set
 262
 263    IGNORE is unused.  */
 264
 265 static void
 266 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
 267                       int which, CORE_ADDR ignore)
 268 {
 269
 270   if (which == 0)
 271     {
 272
 273       /* Integer registers */
 274
 275 #define gregs ((struct regs *)core_reg_sect)
 276       /* G0 *always* holds 0.  */
 277       *(int *) &registers[REGISTER_BYTE (0)] = 0;
 278
 279       /* The globals and output registers.  */
 280       memcpy (&registers[REGISTER_BYTE (G1_REGNUM)], &gregs->r_g1,
 281               15 * REGISTER_RAW_SIZE (G1_REGNUM));
 282       *(int *) &registers[REGISTER_BYTE (PS_REGNUM)] = gregs->r_ps;
 283       *(int *) &registers[REGISTER_BYTE (PC_REGNUM)] = gregs->r_pc;
 284       *(int *) &registers[REGISTER_BYTE (NPC_REGNUM)] = gregs->r_npc;
 285       *(int *) &registers[REGISTER_BYTE (Y_REGNUM)] = gregs->r_y;
 286
 287       /* My best guess at where to get the locals and input
 288          registers is exactly where they usually are, right above
 289          the stack pointer.  If the core dump was caused by a bus error
 290          from blowing away the stack pointer (as is possible) then this
 291          won't work, but it's worth the try. */
 292       {
 293         int sp;
 294
 295         sp = *(int *) &registers[REGISTER_BYTE (SP_REGNUM)];
 296         if (0 != target_read_memory (sp, &registers[REGISTER_BYTE (L0_REGNUM)],
 297                                      16 * REGISTER_RAW_SIZE (L0_REGNUM)))
 298           {
 299             /* fprintf_unfiltered so user can still use gdb */
 300             fprintf_unfiltered (gdb_stderr,
 301                 "Couldn't read input and local registers from core file\n");
 302           }
 303       }
 304     }
 305   else if (which == 2)
 306     {
 307
 308       /* Floating point registers */
 309
 310 #define fpuregs  ((struct fpu *) core_reg_sect)
 311       if (core_reg_size >= sizeof (struct fpu))
 312         {
 313           memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)], fpuregs->fpu_regs,
 314                   sizeof (fpuregs->fpu_regs));
 315           memcpy (&registers[REGISTER_BYTE (FPS_REGNUM)], &fpuregs->fpu_fsr,
 316                   sizeof (FPU_FSR_TYPE));
 317         }
 318       else
 319         fprintf_unfiltered (gdb_stderr, "Couldn't read float regs from core file\n");
 320     }
 321 }
 322
 323 int
 324 kernel_u_size (void)
 325 {
 326   return (sizeof (struct user));
 327 }
 328 \f
 329
 330 /* Register that we are able to handle sparc core file formats.
 331    FIXME: is this really bfd_target_unknown_flavour? */
 332
 333 static struct core_fns sparc_core_fns =
 334 {
 335   bfd_target_unknown_flavour,           /* core_flavour */
 336   default_check_format,                 /* check_format */
 337   default_core_sniffer,                 /* core_sniffer */
 338   fetch_core_registers,                 /* core_read_registers */
 339   NULL                                  /* next */
 340 };
 341
 342 void
 343 _initialize_core_sparc (void)
 344 {
 345   add_core_fns (&sparc_core_fns);
 346 }