gdb/alpha-nat.c

   1 /* Low level Alpha interface, for GDB when running native.
   2    Copyright 1993, 1995, 1996, 1998 Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 #include "defs.h"
  21 #include "inferior.h"
  22 #include "gdbcore.h"
  23 #include "target.h"
  24 #include <sys/ptrace.h>
  25 #ifdef __linux__
  26 # include <asm/reg.h>
  27 # include <alpha/ptrace.h>
  28 #else
  29 # include <machine/reg.h>
  30 #endif
  31 #include <sys/user.h>
  32
  33 static void fetch_osf_core_registers PARAMS ((char *,
  34                                               unsigned, int, CORE_ADDR));
  35 static void fetch_elf_core_registers PARAMS ((char *,
  36                                               unsigned, int, CORE_ADDR));
  37
  38 /* Size of elements in jmpbuf */
  39
  40 #define JB_ELEMENT_SIZE 8
  41
  42 /* The definition for JB_PC in machine/reg.h is wrong.
  43    And we can't get at the correct definition in setjmp.h as it is
  44    not always available (eg. if _POSIX_SOURCE is defined which is the
  45    default). As the defintion is unlikely to change (see comment
  46    in <setjmp.h>, define the correct value here.  */
  47
  48 #undef JB_PC
  49 #define JB_PC 2
  50
  51 /* Figure out where the longjmp will land.
  52    We expect the first arg to be a pointer to the jmp_buf structure from which
  53    we extract the pc (JB_PC) that we will land at.  The pc is copied into PC.
  54    This routine returns true on success. */
  55
  56 int
  57 get_longjmp_target (pc)
  58      CORE_ADDR *pc;
  59 {
  60   CORE_ADDR jb_addr;
  61   char raw_buffer[MAX_REGISTER_RAW_SIZE];
  62
  63   jb_addr = read_register(A0_REGNUM);
  64
  65   if (target_read_memory(jb_addr + JB_PC * JB_ELEMENT_SIZE, raw_buffer,
  66                          sizeof(CORE_ADDR)))
  67     return 0;
  68
  69   *pc = extract_address (raw_buffer, sizeof(CORE_ADDR));
  70   return 1;
  71 }
  72
  73 /* Extract the register values out of the core file and store
  74    them where `read_register' will find them.
  75
  76    CORE_REG_SECT points to the register values themselves, read into memory.
  77    CORE_REG_SIZE is the size of that area.
  78    WHICH says which set of registers we are handling (0 = int, 2 = float
  79          on machines where they are discontiguous).
  80    REG_ADDR is the offset from u.u_ar0 to the register values relative to
  81             core_reg_sect.  This is used with old-fashioned core files to
  82             locate the registers in a large upage-plus-stack ".reg" section.
  83             Original upage address X is at location core_reg_sect+x+reg_addr.
  84  */
  85
  86 static void
  87 fetch_osf_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
  88      char *core_reg_sect;
  89      unsigned core_reg_size;
  90      int which;
  91      CORE_ADDR reg_addr;
  92 {
  93   register int regno;
  94   register int addr;
  95   int bad_reg = -1;
  96
  97   /* Table to map a gdb regnum to an index in the core register section.
  98      The floating point register values are garbage in OSF/1.2 core files.  */
  99   static int core_reg_mapping[NUM_REGS] =
 100   {
 101 #define EFL (EF_SIZE / 8)
 102         EF_V0,  EF_T0,  EF_T1,  EF_T2,  EF_T3,  EF_T4,  EF_T5,  EF_T6,
 103         EF_T7,  EF_S0,  EF_S1,  EF_S2,  EF_S3,  EF_S4,  EF_S5,  EF_S6,
 104         EF_A0,  EF_A1,  EF_A2,  EF_A3,  EF_A4,  EF_A5,  EF_T8,  EF_T9,
 105         EF_T10, EF_T11, EF_RA,  EF_T12, EF_AT,  EF_GP,  EF_SP,  -1,
 106         EFL+0,  EFL+1,  EFL+2,  EFL+3,  EFL+4,  EFL+5,  EFL+6,  EFL+7,
 107         EFL+8,  EFL+9,  EFL+10, EFL+11, EFL+12, EFL+13, EFL+14, EFL+15,
 108         EFL+16, EFL+17, EFL+18, EFL+19, EFL+20, EFL+21, EFL+22, EFL+23,
 109         EFL+24, EFL+25, EFL+26, EFL+27, EFL+28, EFL+29, EFL+30, EFL+31,
 110         EF_PC,  -1
 111   };
 112   static char zerobuf[MAX_REGISTER_RAW_SIZE] = {0};
 113
 114   for (regno = 0; regno < NUM_REGS; regno++)
 115     {
 116       if (CANNOT_FETCH_REGISTER (regno))
 117         {
 118           supply_register (regno, zerobuf);
 119           continue;
 120         }
 121       addr = 8 * core_reg_mapping[regno];
 122       if (addr < 0 || addr >= core_reg_size)
 123         {
 124           if (bad_reg < 0)
 125             bad_reg = regno;
 126         }
 127       else
 128         {
 129           supply_register (regno, core_reg_sect + addr);
 130         }
 131     }
 132   if (bad_reg >= 0)
 133     {
 134       error ("Register %s not found in core file.", reg_names[bad_reg]);
 135     }
 136 }
 137
 138 static void
 139 fetch_elf_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
 140      char *core_reg_sect;
 141      unsigned core_reg_size;
 142      int which;
 143      CORE_ADDR reg_addr;
 144 {
 145   if (core_reg_size < 32*8)
 146     {
 147       error ("Core file register section too small (%u bytes).", core_reg_size);
 148       return;
 149     }
 150
 151   if (which == 2)
 152     {
 153       /* The FPU Registers.  */
 154       memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)], core_reg_sect, 31*8);
 155       memset (&registers[REGISTER_BYTE (FP0_REGNUM+31)], 0, 8);
 156       memset (&register_valid[FP0_REGNUM], 1, 32);
 157     }
 158   else
 159     {
 160       /* The General Registers.  */
 161       memcpy (&registers[REGISTER_BYTE (V0_REGNUM)], core_reg_sect, 31*8);
 162       memcpy (&registers[REGISTER_BYTE (PC_REGNUM)], core_reg_sect+31*8, 8);
 163       memset (&registers[REGISTER_BYTE (ZERO_REGNUM)], 0, 8);
 164       memset (&register_valid[V0_REGNUM], 1, 32);
 165       register_valid[PC_REGNUM] = 1;
 166     }
 167 }
 168
 169
 170 /* Map gdb internal register number to a ptrace ``address''.
 171    These ``addresses'' are defined in <sys/ptrace.h> */
 172
 173 #define REGISTER_PTRACE_ADDR(regno) \
 174    (regno < FP0_REGNUM ?        GPR_BASE + (regno) \
 175   : regno == PC_REGNUM ?        PC      \
 176   : regno >= FP0_REGNUM ?       FPR_BASE + ((regno) - FP0_REGNUM) \
 177   : 0)
 178
 179 /* Return the ptrace ``address'' of register REGNO. */
 180
 181 CORE_ADDR
 182 register_addr (regno, blockend)
 183      int regno;
 184      CORE_ADDR blockend;
 185 {
 186   return REGISTER_PTRACE_ADDR (regno);
 187 }
 188
 189 int
 190 kernel_u_size ()
 191 {
 192   return (sizeof (struct user));
 193 }
 194
 195 #if defined(USE_PROC_FS) || defined(HAVE_GREGSET_T)
 196 #include <sys/procfs.h>
 197
 198 /*
 199  * See the comment in m68k-tdep.c regarding the utility of these functions.
 200  */
 201
 202 void
 203 supply_gregset (gregsetp)
 204      gregset_t *gregsetp;
 205 {
 206   register int regi;
 207   register long *regp = ALPHA_REGSET_BASE (gregsetp);
 208   static char zerobuf[MAX_REGISTER_RAW_SIZE] = {0};
 209
 210   for (regi = 0; regi < 31; regi++)
 211     supply_register (regi, (char *)(regp + regi));
 212
 213   supply_register (PC_REGNUM, (char *)(regp + 31));
 214
 215   /* Fill inaccessible registers with zero.  */
 216   supply_register (ZERO_REGNUM, zerobuf);
 217   supply_register (FP_REGNUM, zerobuf);
 218 }
 219
 220 void
 221 fill_gregset (gregsetp, regno)
 222      gregset_t *gregsetp;
 223      int regno;
 224 {
 225   int regi;
 226   register long *regp = ALPHA_REGSET_BASE (gregsetp);
 227
 228   for (regi = 0; regi < 31; regi++)
 229     if ((regno == -1) || (regno == regi))
 230       *(regp + regi) = *(long *) &registers[REGISTER_BYTE (regi)];
 231
 232   if ((regno == -1) || (regno == PC_REGNUM))
 233     *(regp + 31) = *(long *) &registers[REGISTER_BYTE (PC_REGNUM)];
 234 }
 235
 236 /*
 237  * Now we do the same thing for floating-point registers.
 238  * Again, see the comments in m68k-tdep.c.
 239  */
 240
 241 void
 242 supply_fpregset (fpregsetp)
 243      fpregset_t *fpregsetp;
 244 {
 245   register int regi;
 246   register long *regp = ALPHA_REGSET_BASE (fpregsetp);
 247
 248   for (regi = 0; regi < 32; regi++)
 249     supply_register (regi + FP0_REGNUM, (char *)(regp + regi));
 250 }
 251
 252 void
 253 fill_fpregset (fpregsetp, regno)
 254      fpregset_t *fpregsetp;
 255      int regno;
 256 {
 257   int regi;
 258   register long *regp = ALPHA_REGSET_BASE (fpregsetp);
 259
 260   for (regi = FP0_REGNUM; regi < FP0_REGNUM + 32; regi++)
 261     {
 262       if ((regno == -1) || (regno == regi))
 263         {
 264           *(regp + regi - FP0_REGNUM) =
 265             *(long *) &registers[REGISTER_BYTE (regi)];
 266         }
 267     }
 268 }
 269 #endif
 270
 271 \f
 272 /* Register that we are able to handle alpha core file formats. */
 273
 274 static struct core_fns alpha_osf_core_fns =
 275 {
 276   /* This really is bfd_target_unknown_flavour.  */
 277
 278   bfd_target_unknown_flavour,
 279   fetch_osf_core_registers,
 280   NULL
 281 };
 282
 283 static struct core_fns alpha_elf_core_fns =
 284 {
 285   bfd_target_elf_flavour,
 286   fetch_elf_core_registers,
 287   NULL
 288 };
 289
 290 void
 291 _initialize_core_alpha ()
 292 {
 293   add_core_fns (&alpha_osf_core_fns);
 294   add_core_fns (&alpha_elf_core_fns);
 295 }