gdb/sparcnbsd-tdep.c

   1 /* Target-dependent code for NetBSD/sparc.
   2
   3    Copyright 2002, 2003, 2004 Free Software Foundation, Inc.
   4    Contributed by Wasabi Systems, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 59 Temple Place - Suite 330,
  21    Boston, MA 02111-1307, USA.  */
  22
  23 #include "defs.h"
  24 #include "floatformat.h"
  25 #include "frame.h"
  26 #include "frame-unwind.h"
  27 #include "gdbcore.h"
  28 #include "osabi.h"
  29 #include "regcache.h"
  30 #include "solib-svr4.h"
  31 #include "symtab.h"
  32 #include "trad-frame.h"
  33
  34 #include "gdb_assert.h"
  35 #include "gdb_string.h"
  36
  37 #include "sparc-tdep.h"
  38 #include "nbsd-tdep.h"
  39
  40 const struct sparc_gregset sparc32nbsd_gregset =
  41 {
  42   0 * 4,                        /* %psr */
  43   1 * 4,                        /* %pc */
  44   2 * 4,                        /* %npc */
  45   3 * 4,                        /* %y */
  46   -1,                           /* %wim */
  47   -1,                           /* %tbr */
  48   5 * 4,                        /* %g1 */
  49   -1                            /* %l0 */
  50 };
  51
  52 /* Unlike other NetBSD implementations, the SPARC port historically
  53    used .reg and .reg2 (see bfd/netbsd-core.c), and as such, we can
  54    share one routine for a.out and ELF core files.  */
  55
  56 static void
  57 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size, int which,
  58                       CORE_ADDR ignore)
  59 {
  60   int reg_size = 20 * 4;
  61   int fpreg_size = 33 * 4;
  62
  63   switch (which)
  64     {
  65     case 0:  /* Integer registers.  */
  66       if (core_reg_size != reg_size)
  67         warning ("Wrong size register set in core file.");
  68       sparc32_supply_gregset (&sparc32nbsd_gregset, current_regcache,
  69                               -1, core_reg_sect);
  70       break;
  71
  72     case 2:  /* Floating pointer registers.  */
  73       if (core_reg_size != fpreg_size)
  74         warning ("Wrong size FP register set in core file.");
  75       sparc32_supply_fpregset (current_regcache, -1, core_reg_sect);
  76       break;
  77
  78     default:
  79       /* Don't know what kind of register request this is; just ignore it.  */
  80       break;
  81     }
  82 }
  83
  84 static struct core_fns sparcnbsd_core_fns =
  85 {
  86   bfd_target_unknown_flavour,           /* core_flavour */
  87   default_check_format,                 /* check_format */
  88   default_core_sniffer,                 /* core_sniffer */
  89   fetch_core_registers,                 /* core_read_registers */
  90   NULL
  91 };
  92
  93 static struct core_fns sparcnbsd_elfcore_fns =
  94 {
  95   bfd_target_elf_flavour,               /* core_flavour */
  96   default_check_format,                 /* check_format */
  97   default_core_sniffer,                 /* core_sniffer */
  98   fetch_core_registers,                 /* core_read_registers */
  99   NULL
 100 };
 101 \f
 102 /* Signal trampolines.  */
 103
 104 /* The following variables describe the location of an on-stack signal
 105    trampoline.  The current values correspond to the memory layout for
 106    NetBSD 1.3 and up.  These shouldn't be necessary for NetBSD 2.0 and
 107    up, since NetBSD uses signal trampolines provided by libc now.  */
 108
 109 static const CORE_ADDR sparc32nbsd_sigtramp_start = 0xeffffef0;
 110 static const CORE_ADDR sparc32nbsd_sigtramp_end = 0xeffffff0;
 111
 112 static int
 113 sparc32nbsd_pc_in_sigtramp (CORE_ADDR pc, char *name)
 114 {
 115   if (pc >= sparc32nbsd_sigtramp_start && pc < sparc32nbsd_sigtramp_end)
 116     return 1;
 117
 118   return nbsd_pc_in_sigtramp (pc, name);
 119 }
 120
 121 static struct sparc_frame_cache *
 122 sparc32nbsd_sigcontext_frame_cache (struct frame_info *next_frame,
 123                                     void **this_cache)
 124 {
 125   struct sparc_frame_cache *cache;
 126   CORE_ADDR addr, sigcontext_addr;
 127   LONGEST psr;
 128   int regnum, delta;
 129
 130   if (*this_cache)
 131     return *this_cache;
 132
 133   cache = sparc_frame_cache (next_frame, this_cache);
 134   gdb_assert (cache == *this_cache);
 135
 136   /* The registers are saved in bits and pieces scattered all over the
 137      place.  The code below records their location on the assumption
 138      that the part of the signal trampoline that saves the state has
 139      been executed.  */
 140
 141   /* If we couldn't find the frame's function, we're probably dealing
 142      with an on-stack signal trampoline.  */
 143   if (cache->pc == 0)
 144     {
 145       cache->pc = sparc32nbsd_sigtramp_start;
 146
 147       /* Since we couldn't find the frame's function, the cache was
 148          initialized under the assumption that we're frameless.  */
 149       cache->frameless_p = 0;
 150       addr = frame_unwind_register_unsigned (next_frame, SPARC_FP_REGNUM);
 151       cache->base = addr;
 152     }
 153
 154   cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
 155
 156   /* We find the appropriate instance of `struct sigcontext' at a
 157      fixed offset in the signal frame.  */
 158   sigcontext_addr = cache->base + 64 + 16;
 159
 160   cache->saved_regs[SPARC_SP_REGNUM].addr = sigcontext_addr + 8;
 161   cache->saved_regs[SPARC32_PC_REGNUM].addr = sigcontext_addr + 12;
 162   cache->saved_regs[SPARC32_NPC_REGNUM].addr = sigcontext_addr + 16;
 163   cache->saved_regs[SPARC32_PSR_REGNUM].addr = sigcontext_addr + 20;
 164   cache->saved_regs[SPARC_G1_REGNUM].addr = sigcontext_addr + 24;
 165   cache->saved_regs[SPARC_O0_REGNUM].addr = sigcontext_addr + 28;
 166
 167   /* The remaining `global' registers and %y are saved in the `local'
 168      registers.  */
 169   delta = SPARC_L0_REGNUM - SPARC_G0_REGNUM;
 170   for (regnum = SPARC_G2_REGNUM; regnum <= SPARC_G7_REGNUM; regnum++)
 171     cache->saved_regs[regnum].realreg = regnum + delta;
 172   cache->saved_regs[SPARC32_Y_REGNUM].realreg = SPARC_L1_REGNUM;
 173
 174   /* The remaining `out' registers can be found in the current frame's
 175      `in' registers.  */
 176   delta = SPARC_I0_REGNUM - SPARC_O0_REGNUM;
 177   for (regnum = SPARC_O1_REGNUM; regnum <= SPARC_O5_REGNUM; regnum++)
 178     cache->saved_regs[regnum].realreg = regnum + delta;
 179   cache->saved_regs[SPARC_O7_REGNUM].realreg = SPARC_I7_REGNUM;
 180
 181   /* The `local' and `in' registers have been saved in the register
 182      save area.  */
 183   addr = cache->saved_regs[SPARC_SP_REGNUM].addr;
 184   addr = get_frame_memory_unsigned (next_frame, addr, 4);
 185   for (regnum = SPARC_L0_REGNUM;
 186        regnum <= SPARC_I7_REGNUM; regnum++, addr += 4)
 187     cache->saved_regs[regnum].addr = addr;
 188
 189   /* The floating-point registers are only saved if the EF bit in %prs
 190      has been set.  */
 191
 192 #define PSR_EF  0x00001000
 193
 194   addr = cache->saved_regs[SPARC32_PSR_REGNUM].addr;
 195   psr = get_frame_memory_unsigned (next_frame, addr, 4);
 196   if (psr & PSR_EF)
 197     {
 198       CORE_ADDR sp;
 199
 200       sp = frame_unwind_register_unsigned (next_frame, SPARC_SP_REGNUM);
 201       cache->saved_regs[SPARC32_FSR_REGNUM].addr = sp + 96;
 202       for (regnum = SPARC_F0_REGNUM, addr = sp + 96 + 8;
 203            regnum <= SPARC_F31_REGNUM; regnum++, addr += 4)
 204         cache->saved_regs[regnum].addr = addr;
 205     }
 206
 207   return cache;
 208 }
 209
 210 static void
 211 sparc32nbsd_sigcontext_frame_this_id (struct frame_info *next_frame,
 212                                       void **this_cache,
 213                                       struct frame_id *this_id)
 214 {
 215   struct sparc_frame_cache *cache =
 216     sparc32nbsd_sigcontext_frame_cache (next_frame, this_cache);
 217
 218   (*this_id) = frame_id_build (cache->base, cache->pc);
 219 }
 220
 221 static void
 222 sparc32nbsd_sigcontext_frame_prev_register (struct frame_info *next_frame,
 223                                             void **this_cache,
 224                                             int regnum, int *optimizedp,
 225                                             enum lval_type *lvalp,
 226                                             CORE_ADDR *addrp,
 227                                             int *realnump, void *valuep)
 228 {
 229   struct sparc_frame_cache *cache =
 230     sparc32nbsd_sigcontext_frame_cache (next_frame, this_cache);
 231
 232   trad_frame_prev_register (next_frame, cache->saved_regs, regnum,
 233                             optimizedp, lvalp, addrp, realnump, valuep);
 234 }
 235
 236 static const struct frame_unwind sparc32nbsd_sigcontext_frame_unwind =
 237 {
 238   SIGTRAMP_FRAME,
 239   sparc32nbsd_sigcontext_frame_this_id,
 240   sparc32nbsd_sigcontext_frame_prev_register
 241 };
 242
 243 static const struct frame_unwind *
 244 sparc32nbsd_sigtramp_frame_sniffer (struct frame_info *next_frame)
 245 {
 246   CORE_ADDR pc = frame_pc_unwind (next_frame);
 247   char *name;
 248
 249   find_pc_partial_function (pc, &name, NULL, NULL);
 250   if (sparc32nbsd_pc_in_sigtramp (pc, name))
 251     {
 252       if (name == NULL || strncmp (name, "__sigtramp_sigcontext", 21))
 253         return &sparc32nbsd_sigcontext_frame_unwind;
 254     }
 255
 256   return NULL;
 257 }
 258 \f
 259
 260 /* Return non-zero if we are in a shared library trampoline code stub.  */
 261
 262 static int
 263 sparcnbsd_aout_in_solib_call_trampoline (CORE_ADDR pc, char *name)
 264 {
 265   return (name && !strcmp (name, "_DYNAMIC"));
 266 }
 267
 268 static void
 269 sparc32nbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 270 {
 271   /* NetBSD doesn't support the 128-bit `long double' from the psABI.  */
 272   set_gdbarch_long_double_bit (gdbarch, 64);
 273   set_gdbarch_long_double_format (gdbarch, &floatformat_ieee_double_big);
 274
 275   set_gdbarch_pc_in_sigtramp (gdbarch, sparc32nbsd_pc_in_sigtramp);
 276   frame_unwind_append_sniffer (gdbarch, sparc32nbsd_sigtramp_frame_sniffer);
 277 }
 278
 279 static void
 280 sparc32nbsd_aout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 281 {
 282   sparc32nbsd_init_abi (info, gdbarch);
 283
 284   set_gdbarch_in_solib_call_trampoline
 285     (gdbarch, sparcnbsd_aout_in_solib_call_trampoline);
 286 }
 287
 288 static void
 289 sparc32nbsd_elf_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 290 {
 291   sparc32nbsd_init_abi (info, gdbarch);
 292
 293   set_solib_svr4_fetch_link_map_offsets
 294     (gdbarch, nbsd_ilp32_solib_svr4_fetch_link_map_offsets);
 295 }
 296
 297 static enum gdb_osabi
 298 sparcnbsd_aout_osabi_sniffer (bfd *abfd)
 299 {
 300   if (strcmp (bfd_get_target (abfd), "a.out-sparc-netbsd") == 0)
 301     return GDB_OSABI_NETBSD_AOUT;
 302
 303   return GDB_OSABI_UNKNOWN;
 304 }
 305
 306 \f
 307 /* Provide a prototype to silence -Wmissing-prototypes.  */
 308 void _initialize_sparcnbsd_tdep (void);
 309
 310 void
 311 _initialize_sparnbsd_tdep (void)
 312 {
 313   gdbarch_register_osabi_sniffer (bfd_arch_sparc, bfd_target_aout_flavour,
 314                                   sparcnbsd_aout_osabi_sniffer);
 315
 316   gdbarch_register_osabi (bfd_arch_sparc, 0, GDB_OSABI_NETBSD_AOUT,
 317                           sparc32nbsd_aout_init_abi);
 318   gdbarch_register_osabi (bfd_arch_sparc, 0, GDB_OSABI_NETBSD_ELF,
 319                           sparc32nbsd_elf_init_abi);
 320
 321   add_core_fns (&sparcnbsd_core_fns);
 322   add_core_fns (&sparcnbsd_elfcore_fns);
 323 }