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 "regset.h"
  31 #include "solib-svr4.h"
  32 #include "symtab.h"
  33 #include "trad-frame.h"
  34
  35 #include "gdb_assert.h"
  36 #include "gdb_string.h"
  37
  38 #include "sparc-tdep.h"
  39 #include "nbsd-tdep.h"
  40
  41 const struct sparc_gregset sparc32nbsd_gregset =
  42 {
  43   0 * 4,                        /* %psr */
  44   1 * 4,                        /* %pc */
  45   2 * 4,                        /* %npc */
  46   3 * 4,                        /* %y */
  47   -1,                           /* %wim */
  48   -1,                           /* %tbr */
  49   5 * 4,                        /* %g1 */
  50   -1                            /* %l0 */
  51 };
  52
  53 static void
  54 sparc32nbsd_supply_gregset (const struct regset *regset,
  55                             struct regcache *regcache,
  56                             int regnum, const void *gregs, size_t len)
  57 {
  58   sparc32_supply_gregset (&sparc32nbsd_gregset, regcache, regnum, gregs);
  59
  60   /* Traditional NetBSD core files don't use multiple register sets.
  61      Instead, the general-purpose and floating-point registers are
  62      lumped together in a single section.  */
  63   if (len >= 212)
  64     sparc32_supply_fpregset (regcache, regnum, (const char *) gregs + 80);
  65 }
  66
  67 static void
  68 sparc32nbsd_supply_fpregset (const struct regset *regset,
  69                              struct regcache *regcache,
  70                              int regnum, const void *fpregs, size_t len)
  71 {
  72   sparc32_supply_fpregset (regcache, regnum, fpregs);
  73 }
  74
  75 \f
  76 /* Signal trampolines.  */
  77
  78 /* The following variables describe the location of an on-stack signal
  79    trampoline.  The current values correspond to the memory layout for
  80    NetBSD 1.3 and up.  These shouldn't be necessary for NetBSD 2.0 and
  81    up, since NetBSD uses signal trampolines provided by libc now.  */
  82
  83 static const CORE_ADDR sparc32nbsd_sigtramp_start = 0xeffffef0;
  84 static const CORE_ADDR sparc32nbsd_sigtramp_end = 0xeffffff0;
  85
  86 static int
  87 sparc32nbsd_pc_in_sigtramp (CORE_ADDR pc, char *name)
  88 {
  89   if (pc >= sparc32nbsd_sigtramp_start && pc < sparc32nbsd_sigtramp_end)
  90     return 1;
  91
  92   return nbsd_pc_in_sigtramp (pc, name);
  93 }
  94
  95 struct trad_frame_saved_reg *
  96 sparc32nbsd_sigcontext_saved_regs (struct frame_info *next_frame)
  97 {
  98   struct trad_frame_saved_reg *saved_regs;
  99   CORE_ADDR addr, sigcontext_addr;
 100   int regnum, delta;
 101   ULONGEST psr;
 102
 103   saved_regs = trad_frame_alloc_saved_regs (next_frame);
 104
 105   /* We find the appropriate instance of `struct sigcontext' at a
 106      fixed offset in the signal frame.  */
 107   addr = frame_unwind_register_unsigned (next_frame, SPARC_FP_REGNUM);
 108   sigcontext_addr = addr + 64 + 16;
 109
 110   /* The registers are saved in bits and pieces scattered all over the
 111      place.  The code below records their location on the assumption
 112      that the part of the signal trampoline that saves the state has
 113      been executed.  */
 114
 115   saved_regs[SPARC_SP_REGNUM].addr = sigcontext_addr + 8;
 116   saved_regs[SPARC32_PC_REGNUM].addr = sigcontext_addr + 12;
 117   saved_regs[SPARC32_NPC_REGNUM].addr = sigcontext_addr + 16;
 118   saved_regs[SPARC32_PSR_REGNUM].addr = sigcontext_addr + 20;
 119   saved_regs[SPARC_G1_REGNUM].addr = sigcontext_addr + 24;
 120   saved_regs[SPARC_O0_REGNUM].addr = sigcontext_addr + 28;
 121
 122   /* The remaining `global' registers and %y are saved in the `local'
 123      registers.  */
 124   delta = SPARC_L0_REGNUM - SPARC_G0_REGNUM;
 125   for (regnum = SPARC_G2_REGNUM; regnum <= SPARC_G7_REGNUM; regnum++)
 126     saved_regs[regnum].realreg = regnum + delta;
 127   saved_regs[SPARC32_Y_REGNUM].realreg = SPARC_L1_REGNUM;
 128
 129   /* The remaining `out' registers can be found in the current frame's
 130      `in' registers.  */
 131   delta = SPARC_I0_REGNUM - SPARC_O0_REGNUM;
 132   for (regnum = SPARC_O1_REGNUM; regnum <= SPARC_O5_REGNUM; regnum++)
 133     saved_regs[regnum].realreg = regnum + delta;
 134   saved_regs[SPARC_O7_REGNUM].realreg = SPARC_I7_REGNUM;
 135
 136   /* The `local' and `in' registers have been saved in the register
 137      save area.  */
 138   addr = saved_regs[SPARC_SP_REGNUM].addr;
 139   addr = get_frame_memory_unsigned (next_frame, addr, 4);
 140   for (regnum = SPARC_L0_REGNUM;
 141        regnum <= SPARC_I7_REGNUM; regnum++, addr += 4)
 142     saved_regs[regnum].addr = addr;
 143
 144   /* Handle StackGhost.  */
 145   {
 146     ULONGEST wcookie = sparc_fetch_wcookie ();
 147
 148     if (wcookie != 0)
 149       {
 150         ULONGEST i7;
 151
 152         addr = saved_regs[SPARC_I7_REGNUM].addr;
 153         i7 = get_frame_memory_unsigned (next_frame, addr, 4);
 154         trad_frame_set_value (saved_regs, SPARC_I7_REGNUM, i7 ^ wcookie);
 155       }
 156   }
 157
 158   /* The floating-point registers are only saved if the EF bit in %prs
 159      has been set.  */
 160
 161 #define PSR_EF  0x00001000
 162
 163   addr = saved_regs[SPARC32_PSR_REGNUM].addr;
 164   psr = get_frame_memory_unsigned (next_frame, addr, 4);
 165   if (psr & PSR_EF)
 166     {
 167       CORE_ADDR sp;
 168
 169       sp = frame_unwind_register_unsigned (next_frame, SPARC_SP_REGNUM);
 170       saved_regs[SPARC32_FSR_REGNUM].addr = sp + 96;
 171       for (regnum = SPARC_F0_REGNUM, addr = sp + 96 + 8;
 172            regnum <= SPARC_F31_REGNUM; regnum++, addr += 4)
 173         saved_regs[regnum].addr = addr;
 174     }
 175
 176   return saved_regs;
 177 }
 178
 179 static struct sparc_frame_cache *
 180 sparc32nbsd_sigcontext_frame_cache (struct frame_info *next_frame,
 181                                     void **this_cache)
 182 {
 183   struct sparc_frame_cache *cache;
 184   CORE_ADDR addr;
 185
 186   if (*this_cache)
 187     return *this_cache;
 188
 189   cache = sparc_frame_cache (next_frame, this_cache);
 190   gdb_assert (cache == *this_cache);
 191
 192   /* If we couldn't find the frame's function, we're probably dealing
 193      with an on-stack signal trampoline.  */
 194   if (cache->pc == 0)
 195     {
 196       cache->pc = sparc32nbsd_sigtramp_start;
 197
 198       /* Since we couldn't find the frame's function, the cache was
 199          initialized under the assumption that we're frameless.  */
 200       cache->frameless_p = 0;
 201       addr = frame_unwind_register_unsigned (next_frame, SPARC_FP_REGNUM);
 202       cache->base = addr;
 203     }
 204
 205   cache->saved_regs = sparc32nbsd_sigcontext_saved_regs (next_frame);
 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_get_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 static void
 261 sparc32nbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 262 {
 263   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 264
 265   /* NetBSD doesn't support the 128-bit `long double' from the psABI.  */
 266   set_gdbarch_long_double_bit (gdbarch, 64);
 267   set_gdbarch_long_double_format (gdbarch, &floatformat_ieee_double_big);
 268
 269   tdep->gregset = regset_alloc (gdbarch, sparc32nbsd_supply_gregset, NULL);
 270   tdep->sizeof_gregset = 20 * 4;
 271
 272   tdep->fpregset = regset_alloc (gdbarch, sparc32nbsd_supply_fpregset, NULL);
 273   tdep->sizeof_fpregset = 33 * 4;
 274
 275   frame_unwind_append_sniffer (gdbarch, sparc32nbsd_sigtramp_frame_sniffer);
 276 }
 277
 278 static void
 279 sparc32nbsd_aout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 280 {
 281   sparc32nbsd_init_abi (info, gdbarch);
 282 }
 283
 284 void
 285 sparc32nbsd_elf_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 286 {
 287   sparc32nbsd_init_abi (info, gdbarch);
 288
 289   set_solib_svr4_fetch_link_map_offsets
 290     (gdbarch, svr4_ilp32_fetch_link_map_offsets);
 291 }
 292
 293 static enum gdb_osabi
 294 sparcnbsd_aout_osabi_sniffer (bfd *abfd)
 295 {
 296   if (strcmp (bfd_get_target (abfd), "a.out-sparc-netbsd") == 0)
 297     return GDB_OSABI_NETBSD_AOUT;
 298
 299   return GDB_OSABI_UNKNOWN;
 300 }
 301
 302 /* OpenBSD uses the traditional NetBSD core file format, even for
 303    ports that use ELF.  Therefore, if the default OS ABI is OpenBSD
 304    ELF, we return that instead of NetBSD a.out.  This is mainly for
 305    the benfit of OpenBSD/sparc64, which inherits the sniffer below
 306    since we include this file for an OpenBSD/sparc64 target.  For
 307    OpenBSD/sparc, the NetBSD a.out OS ABI is probably similar enough
 308    to both the OpenBSD a.out and the OpenBSD ELF OS ABI.  */
 309 #if defined (GDB_OSABI_DEFAULT) && (GDB_OSABI_DEFAULT == GDB_OSABI_OPENBSD_ELF)
 310 #define GDB_OSABI_NETBSD_CORE GDB_OSABI_OPENBSD_ELF
 311 #else
 312 #define GDB_OSABI_NETBSD_CORE GDB_OSABI_NETBSD_AOUT
 313 #endif
 314
 315 static enum gdb_osabi
 316 sparcnbsd_core_osabi_sniffer (bfd *abfd)
 317 {
 318   if (strcmp (bfd_get_target (abfd), "netbsd-core") == 0)
 319     return GDB_OSABI_NETBSD_CORE;
 320
 321   return GDB_OSABI_UNKNOWN;
 322 }
 323
 324 \f
 325 /* Provide a prototype to silence -Wmissing-prototypes.  */
 326 void _initialize_sparcnbsd_tdep (void);
 327
 328 void
 329 _initialize_sparnbsd_tdep (void)
 330 {
 331   gdbarch_register_osabi_sniffer (bfd_arch_sparc, bfd_target_aout_flavour,
 332                                   sparcnbsd_aout_osabi_sniffer);
 333
 334   /* BFD doesn't set a flavour for NetBSD style a.out core files.  */
 335   gdbarch_register_osabi_sniffer (bfd_arch_sparc, bfd_target_unknown_flavour,
 336                                   sparcnbsd_core_osabi_sniffer);
 337
 338   gdbarch_register_osabi (bfd_arch_sparc, 0, GDB_OSABI_NETBSD_AOUT,
 339                           sparc32nbsd_aout_init_abi);
 340   gdbarch_register_osabi (bfd_arch_sparc, 0, GDB_OSABI_NETBSD_ELF,
 341                           sparc32nbsd_elf_init_abi);
 342 }