gdb/alpha-nat.c

   1 /* Low level Alpha interface, for GDB when running native.
   2    Copyright 1993, 1995, 1996, 1998, 1999, 2000, 2001
   3    Free Software 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 "gdbcore.h"
  25 #include "target.h"
  26 #include "regcache.h"
  27 #include <sys/ptrace.h>
  28 #ifdef __linux__
  29 #include <asm/reg.h>
  30 #include <alpha/ptrace.h>
  31 #else
  32 #include <alpha/coreregs.h>
  33 #endif
  34 #include <sys/user.h>
  35
  36 /* Prototypes for local functions. */
  37
  38 static void fetch_osf_core_registers (char *, unsigned, int, CORE_ADDR);
  39 static void fetch_elf_core_registers (char *, unsigned, int, CORE_ADDR);
  40
  41 /* Size of elements in jmpbuf */
  42
  43 #define JB_ELEMENT_SIZE 8
  44
  45 /* The definition for JB_PC in machine/reg.h is wrong.
  46    And we can't get at the correct definition in setjmp.h as it is
  47    not always available (eg. if _POSIX_SOURCE is defined which is the
  48    default). As the defintion is unlikely to change (see comment
  49    in <setjmp.h>, define the correct value here.  */
  50
  51 #undef JB_PC
  52 #define JB_PC 2
  53
  54 /* Figure out where the longjmp will land.
  55    We expect the first arg to be a pointer to the jmp_buf structure from which
  56    we extract the pc (JB_PC) that we will land at.  The pc is copied into PC.
  57    This routine returns true on success. */
  58
  59 int
  60 get_longjmp_target (CORE_ADDR *pc)
  61 {
  62   CORE_ADDR jb_addr;
  63   char raw_buffer[MAX_REGISTER_RAW_SIZE];
  64
  65   jb_addr = read_register (A0_REGNUM);
  66
  67   if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, raw_buffer,
  68                           sizeof (CORE_ADDR)))
  69     return 0;
  70
  71   *pc = extract_address (raw_buffer, sizeof (CORE_ADDR));
  72   return 1;
  73 }
  74
  75 /* Extract the register values out of the core file and store
  76    them where `read_register' will find them.
  77
  78    CORE_REG_SECT points to the register values themselves, read into memory.
  79    CORE_REG_SIZE is the size of that area.
  80    WHICH says which set of registers we are handling (0 = int, 2 = float
  81    on machines where they are discontiguous).
  82    REG_ADDR is the offset from u.u_ar0 to the register values relative to
  83    core_reg_sect.  This is used with old-fashioned core files to
  84    locate the registers in a large upage-plus-stack ".reg" section.
  85    Original upage address X is at location core_reg_sect+x+reg_addr.
  86  */
  87
  88 static void
  89 fetch_osf_core_registers (char *core_reg_sect, unsigned core_reg_size,
  90                           int which, CORE_ADDR reg_addr)
  91 {
  92   register int regno;
  93   register int addr;
  94   int bad_reg = -1;
  95
  96   /* Table to map a gdb regnum to an index in the core register
  97      section.  The floating point register values are garbage in
  98      OSF/1.2 core files.  OSF5 uses different names for the register
  99      enum list, need to handle two cases.  The actual values are the
 100      same.  */
 101   static int core_reg_mapping[NUM_REGS] =
 102   {
 103 #ifdef NCF_REGS
 104 #define EFL NCF_REGS
 105     CF_V0, CF_T0, CF_T1, CF_T2, CF_T3, CF_T4, CF_T5, CF_T6,
 106     CF_T7, CF_S0, CF_S1, CF_S2, CF_S3, CF_S4, CF_S5, CF_S6,
 107     CF_A0, CF_A1, CF_A2, CF_A3, CF_A4, CF_A5, CF_T8, CF_T9,
 108     CF_T10, CF_T11, CF_RA, CF_T12, CF_AT, CF_GP, CF_SP, -1,
 109     EFL + 0, EFL + 1, EFL + 2, EFL + 3, EFL + 4, EFL + 5, EFL + 6, EFL + 7,
 110     EFL + 8, EFL + 9, EFL + 10, EFL + 11, EFL + 12, EFL + 13, EFL + 14, EFL + 15,
 111     EFL + 16, EFL + 17, EFL + 18, EFL + 19, EFL + 20, EFL + 21, EFL + 22, EFL + 23,
 112     EFL + 24, EFL + 25, EFL + 26, EFL + 27, EFL + 28, EFL + 29, EFL + 30, EFL + 31,
 113     CF_PC, -1
 114 #else
 115 #define EFL (EF_SIZE / 8)
 116     EF_V0, EF_T0, EF_T1, EF_T2, EF_T3, EF_T4, EF_T5, EF_T6,
 117     EF_T7, EF_S0, EF_S1, EF_S2, EF_S3, EF_S4, EF_S5, EF_S6,
 118     EF_A0, EF_A1, EF_A2, EF_A3, EF_A4, EF_A5, EF_T8, EF_T9,
 119     EF_T10, EF_T11, EF_RA, EF_T12, EF_AT, EF_GP, EF_SP, -1,
 120     EFL + 0, EFL + 1, EFL + 2, EFL + 3, EFL + 4, EFL + 5, EFL + 6, EFL + 7,
 121     EFL + 8, EFL + 9, EFL + 10, EFL + 11, EFL + 12, EFL + 13, EFL + 14, EFL + 15,
 122     EFL + 16, EFL + 17, EFL + 18, EFL + 19, EFL + 20, EFL + 21, EFL + 22, EFL + 23,
 123     EFL + 24, EFL + 25, EFL + 26, EFL + 27, EFL + 28, EFL + 29, EFL + 30, EFL + 31,
 124     EF_PC, -1
 125 #endif
 126   };
 127   static char zerobuf[MAX_REGISTER_RAW_SIZE] =
 128   {0};
 129
 130   for (regno = 0; regno < NUM_REGS; regno++)
 131     {
 132       if (CANNOT_FETCH_REGISTER (regno))
 133         {
 134           supply_register (regno, zerobuf);
 135           continue;
 136         }
 137       addr = 8 * core_reg_mapping[regno];
 138       if (addr < 0 || addr >= core_reg_size)
 139         {
 140           if (bad_reg < 0)
 141             bad_reg = regno;
 142         }
 143       else
 144         {
 145           supply_register (regno, core_reg_sect + addr);
 146         }
 147     }
 148   if (bad_reg >= 0)
 149     {
 150       error ("Register %s not found in core file.", REGISTER_NAME (bad_reg));
 151     }
 152 }
 153
 154 static void
 155 fetch_elf_core_registers (char *core_reg_sect, unsigned core_reg_size,
 156                           int which, CORE_ADDR reg_addr)
 157 {
 158   if (core_reg_size < 32 * 8)
 159     {
 160       error ("Core file register section too small (%u bytes).", core_reg_size);
 161       return;
 162     }
 163
 164   if (which == 2)
 165     {
 166       /* The FPU Registers.  */
 167       memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)], core_reg_sect, 31 * 8);
 168       memset (&registers[REGISTER_BYTE (FP0_REGNUM + 31)], 0, 8);
 169       memset (&register_valid[FP0_REGNUM], 1, 32);
 170     }
 171   else
 172     {
 173       /* The General Registers.  */
 174       memcpy (&registers[REGISTER_BYTE (V0_REGNUM)], core_reg_sect, 31 * 8);
 175       memcpy (&registers[REGISTER_BYTE (PC_REGNUM)], core_reg_sect + 31 * 8, 8);
 176       memset (&registers[REGISTER_BYTE (ZERO_REGNUM)], 0, 8);
 177       memset (&register_valid[V0_REGNUM], 1, 32);
 178       register_valid[PC_REGNUM] = 1;
 179     }
 180 }
 181
 182
 183 /* Map gdb internal register number to a ptrace ``address''.
 184    These ``addresses'' are defined in <sys/ptrace.h> */
 185
 186 #define REGISTER_PTRACE_ADDR(regno) \
 187    (regno < FP0_REGNUM ?        GPR_BASE + (regno) \
 188   : regno == PC_REGNUM ?        PC      \
 189   : regno >= FP0_REGNUM ?       FPR_BASE + ((regno) - FP0_REGNUM) \
 190   : 0)
 191
 192 /* Return the ptrace ``address'' of register REGNO. */
 193
 194 CORE_ADDR
 195 register_addr (int regno, CORE_ADDR blockend)
 196 {
 197   return REGISTER_PTRACE_ADDR (regno);
 198 }
 199
 200 int
 201 kernel_u_size (void)
 202 {
 203   return (sizeof (struct user));
 204 }
 205
 206 #if defined(USE_PROC_FS) || defined(HAVE_GREGSET_T)
 207 #include <sys/procfs.h>
 208
 209 /* Prototypes for supply_gregset etc. */
 210 #include "gregset.h"
 211
 212 /*
 213  * See the comment in m68k-tdep.c regarding the utility of these functions.
 214  */
 215
 216 void
 217 supply_gregset (gdb_gregset_t *gregsetp)
 218 {
 219   register int regi;
 220   register long *regp = ALPHA_REGSET_BASE (gregsetp);
 221   static char zerobuf[MAX_REGISTER_RAW_SIZE] =
 222   {0};
 223
 224   for (regi = 0; regi < 31; regi++)
 225     supply_register (regi, (char *) (regp + regi));
 226
 227   supply_register (PC_REGNUM, (char *) (regp + 31));
 228
 229   /* Fill inaccessible registers with zero.  */
 230   supply_register (ZERO_REGNUM, zerobuf);
 231   supply_register (FP_REGNUM, zerobuf);
 232 }
 233
 234 void
 235 fill_gregset (gdb_gregset_t *gregsetp, int regno)
 236 {
 237   int regi;
 238   register long *regp = ALPHA_REGSET_BASE (gregsetp);
 239
 240   for (regi = 0; regi < 31; regi++)
 241     if ((regno == -1) || (regno == regi))
 242       *(regp + regi) = *(long *) &registers[REGISTER_BYTE (regi)];
 243
 244   if ((regno == -1) || (regno == PC_REGNUM))
 245     *(regp + 31) = *(long *) &registers[REGISTER_BYTE (PC_REGNUM)];
 246 }
 247
 248 /*
 249  * Now we do the same thing for floating-point registers.
 250  * Again, see the comments in m68k-tdep.c.
 251  */
 252
 253 void
 254 supply_fpregset (gdb_fpregset_t *fpregsetp)
 255 {
 256   register int regi;
 257   register long *regp = ALPHA_REGSET_BASE (fpregsetp);
 258
 259   for (regi = 0; regi < 32; regi++)
 260     supply_register (regi + FP0_REGNUM, (char *) (regp + regi));
 261 }
 262
 263 void
 264 fill_fpregset (gdb_fpregset_t *fpregsetp, int regno)
 265 {
 266   int regi;
 267   register long *regp = ALPHA_REGSET_BASE (fpregsetp);
 268
 269   for (regi = FP0_REGNUM; regi < FP0_REGNUM + 32; regi++)
 270     {
 271       if ((regno == -1) || (regno == regi))
 272         {
 273           *(regp + regi - FP0_REGNUM) =
 274             *(long *) &registers[REGISTER_BYTE (regi)];
 275         }
 276     }
 277 }
 278 #endif
 279 \f
 280
 281 /* Register that we are able to handle alpha core file formats. */
 282
 283 static struct core_fns alpha_osf_core_fns =
 284 {
 285   /* This really is bfd_target_unknown_flavour.  */
 286
 287   bfd_target_unknown_flavour,           /* core_flavour */
 288   default_check_format,                 /* check_format */
 289   default_core_sniffer,                 /* core_sniffer */
 290   fetch_osf_core_registers,             /* core_read_registers */
 291   NULL                                  /* next */
 292 };
 293
 294 static struct core_fns alpha_elf_core_fns =
 295 {
 296   bfd_target_elf_flavour,               /* core_flavour */
 297   default_check_format,                 /* check_format */
 298   default_core_sniffer,                 /* core_sniffer */
 299   fetch_elf_core_registers,             /* core_read_registers */
 300   NULL                                  /* next */
 301 };
 302
 303 void
 304 _initialize_core_alpha (void)
 305 {
 306   add_core_fns (&alpha_osf_core_fns);
 307   add_core_fns (&alpha_elf_core_fns);
 308 }