gdb/sparc64nbsd-tdep.c

   1 /* Target-dependent code for NetBSD/sparc64.
   2
   3    Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
   4    Based on code 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., 51 Franklin Street, Fifth Floor,
  21    Boston, MA 02110-1301, USA.  */
  22
  23 #include "defs.h"
  24 #include "frame.h"
  25 #include "frame-unwind.h"
  26 #include "gdbcore.h"
  27 #include "osabi.h"
  28 #include "regcache.h"
  29 #include "regset.h"
  30 #include "symtab.h"
  31 #include "objfiles.h"
  32 #include "solib-svr4.h"
  33 #include "trad-frame.h"
  34
  35 #include "gdb_assert.h"
  36 #include "gdb_string.h"
  37
  38 #include "sparc64-tdep.h"
  39 #include "nbsd-tdep.h"
  40
  41 /* From <machine/reg.h>.  */
  42 const struct sparc_gregset sparc64nbsd_gregset =
  43 {
  44   0 * 8,                        /* "tstate" */
  45   1 * 8,                        /* %pc */
  46   2 * 8,                        /* %npc */
  47   3 * 8,                        /* %y */
  48   -1,                           /* %fprs */
  49   -1,
  50   5 * 8,                        /* %g1 */
  51   -1,                           /* %l0 */
  52   4                             /* sizeof (%y) */
  53 };
  54 \f
  55
  56 static void
  57 sparc64nbsd_supply_gregset (const struct regset *regset,
  58                             struct regcache *regcache,
  59                             int regnum, const void *gregs, size_t len)
  60 {
  61   sparc64_supply_gregset (&sparc64nbsd_gregset, regcache, regnum, gregs);
  62 }
  63
  64 static void
  65 sparc64nbsd_supply_fpregset (const struct regset *regset,
  66                              struct regcache *regcache,
  67                              int regnum, const void *fpregs, size_t len)
  68 {
  69   sparc64_supply_fpregset (regcache, regnum, fpregs);
  70 }
  71 \f
  72
  73 /* Signal trampolines.  */
  74
  75 /* The following variables describe the location of an on-stack signal
  76    trampoline.  The current values correspond to the memory layout for
  77    NetBSD 1.3 and up.  These shouldn't be necessary for NetBSD 2.0 and
  78    up, since NetBSD uses signal trampolines provided by libc now.  */
  79
  80 static const CORE_ADDR sparc64nbsd_sigtramp_start = 0xffffffffffffdee4ULL;
  81 static const CORE_ADDR sparc64nbsd_sigtramp_end = 0xffffffffffffe000ULL;
  82
  83 static int
  84 sparc64nbsd_pc_in_sigtramp (CORE_ADDR pc, char *name)
  85 {
  86   if (pc >= sparc64nbsd_sigtramp_start && pc < sparc64nbsd_sigtramp_end)
  87     return 1;
  88
  89   return nbsd_pc_in_sigtramp (pc, name);
  90 }
  91
  92 struct trad_frame_saved_reg *
  93 sparc64nbsd_sigcontext_saved_regs (CORE_ADDR sigcontext_addr,
  94                                    struct frame_info *next_frame)
  95 {
  96   struct trad_frame_saved_reg *saved_regs;
  97   CORE_ADDR addr, sp;
  98   int regnum, delta;
  99
 100   saved_regs = trad_frame_alloc_saved_regs (next_frame);
 101
 102   /* The registers are saved in bits and pieces scattered all over the
 103      place.  The code below records their location on the assumption
 104      that the part of the signal trampoline that saves the state has
 105      been executed.  */
 106
 107   saved_regs[SPARC_SP_REGNUM].addr = sigcontext_addr + 8;
 108   saved_regs[SPARC64_PC_REGNUM].addr = sigcontext_addr + 16;
 109   saved_regs[SPARC64_NPC_REGNUM].addr = sigcontext_addr + 24;
 110   saved_regs[SPARC64_STATE_REGNUM].addr = sigcontext_addr + 32;
 111   saved_regs[SPARC_G1_REGNUM].addr = sigcontext_addr + 40;
 112   saved_regs[SPARC_O0_REGNUM].addr = sigcontext_addr + 48;
 113
 114   /* The remaining `global' registers and %y are saved in the `local'
 115      registers.  */
 116   delta = SPARC_L0_REGNUM - SPARC_G0_REGNUM;
 117   for (regnum = SPARC_G2_REGNUM; regnum <= SPARC_G7_REGNUM; regnum++)
 118     saved_regs[regnum].realreg = regnum + delta;
 119   saved_regs[SPARC64_Y_REGNUM].realreg = SPARC_L1_REGNUM;
 120
 121   /* The remaining `out' registers can be found in the current frame's
 122      `in' registers.  */
 123   delta = SPARC_I0_REGNUM - SPARC_O0_REGNUM;
 124   for (regnum = SPARC_O1_REGNUM; regnum <= SPARC_O5_REGNUM; regnum++)
 125     saved_regs[regnum].realreg = regnum + delta;
 126   saved_regs[SPARC_O7_REGNUM].realreg = SPARC_I7_REGNUM;
 127
 128   /* The `local' and `in' registers have been saved in the register
 129      save area.  */
 130   addr = saved_regs[SPARC_SP_REGNUM].addr;
 131   sp = get_frame_memory_unsigned (next_frame, addr, 8);
 132   for (regnum = SPARC_L0_REGNUM, addr = sp + BIAS;
 133        regnum <= SPARC_I7_REGNUM; regnum++, addr += 8)
 134     saved_regs[regnum].addr = addr;
 135
 136   /* Handle StackGhost.  */
 137   {
 138     ULONGEST wcookie = sparc_fetch_wcookie ();
 139
 140     if (wcookie != 0)
 141       {
 142         ULONGEST i7;
 143
 144         addr = saved_regs[SPARC_I7_REGNUM].addr;
 145         i7 = get_frame_memory_unsigned (next_frame, addr, 8);
 146         trad_frame_set_value (saved_regs, SPARC_I7_REGNUM, i7 ^ wcookie);
 147       }
 148   }
 149
 150   /* TODO: Handle the floating-point registers.  */
 151
 152   return saved_regs;
 153 }
 154
 155 static struct sparc_frame_cache *
 156 sparc64nbsd_sigcontext_frame_cache (struct frame_info *next_frame,
 157                                     void **this_cache)
 158 {
 159   struct sparc_frame_cache *cache;
 160   CORE_ADDR addr;
 161
 162   if (*this_cache)
 163     return *this_cache;
 164
 165   cache = sparc_frame_cache (next_frame, this_cache);
 166   gdb_assert (cache == *this_cache);
 167
 168   /* If we couldn't find the frame's function, we're probably dealing
 169      with an on-stack signal trampoline.  */
 170   if (cache->pc == 0)
 171     {
 172       cache->pc = sparc64nbsd_sigtramp_start;
 173
 174       /* Since we couldn't find the frame's function, the cache was
 175          initialized under the assumption that we're frameless.  */
 176       cache->frameless_p = 0;
 177       addr = frame_unwind_register_unsigned (next_frame, SPARC_FP_REGNUM);
 178       if (addr & 1)
 179         addr += BIAS;
 180       cache->base = addr;
 181     }
 182
 183   /* We find the appropriate instance of `struct sigcontext' at a
 184      fixed offset in the signal frame.  */
 185   addr = cache->base + 128 + 8;
 186   cache->saved_regs = sparc64nbsd_sigcontext_saved_regs (addr, next_frame);
 187
 188   return cache;
 189 }
 190
 191 static void
 192 sparc64nbsd_sigcontext_frame_this_id (struct frame_info *next_frame,
 193                                       void **this_cache,
 194                                       struct frame_id *this_id)
 195 {
 196   struct sparc_frame_cache *cache =
 197     sparc64nbsd_sigcontext_frame_cache (next_frame, this_cache);
 198
 199   (*this_id) = frame_id_build (cache->base, cache->pc);
 200 }
 201
 202 static void
 203 sparc64nbsd_sigcontext_frame_prev_register (struct frame_info *next_frame,
 204                                             void **this_cache,
 205                                             int regnum, int *optimizedp,
 206                                             enum lval_type *lvalp,
 207                                             CORE_ADDR *addrp,
 208                                             int *realnump, gdb_byte *valuep)
 209 {
 210   struct sparc_frame_cache *cache =
 211     sparc64nbsd_sigcontext_frame_cache (next_frame, this_cache);
 212
 213   trad_frame_get_prev_register (next_frame, cache->saved_regs, regnum,
 214                                 optimizedp, lvalp, addrp, realnump, valuep);
 215 }
 216
 217 static const struct frame_unwind sparc64nbsd_sigcontext_frame_unwind =
 218 {
 219   SIGTRAMP_FRAME,
 220   sparc64nbsd_sigcontext_frame_this_id,
 221   sparc64nbsd_sigcontext_frame_prev_register
 222 };
 223
 224 static const struct frame_unwind *
 225 sparc64nbsd_sigtramp_frame_sniffer (struct frame_info *next_frame)
 226 {
 227   CORE_ADDR pc = frame_pc_unwind (next_frame);
 228   char *name;
 229
 230   find_pc_partial_function (pc, &name, NULL, NULL);
 231   if (sparc64nbsd_pc_in_sigtramp (pc, name))
 232     {
 233       if (name == NULL || strncmp (name, "__sigtramp_sigcontext", 21))
 234         return &sparc64nbsd_sigcontext_frame_unwind;
 235     }
 236
 237   return NULL;
 238 }
 239 \f
 240
 241 static void
 242 sparc64nbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 243 {
 244   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 245
 246   tdep->gregset = regset_alloc (gdbarch, sparc64nbsd_supply_gregset, NULL);
 247   tdep->sizeof_gregset = 160;
 248
 249   tdep->fpregset = regset_alloc (gdbarch, sparc64nbsd_supply_fpregset, NULL);
 250   tdep->sizeof_fpregset = 272;
 251
 252   /* Make sure we can single-step "new" syscalls.  */
 253   tdep->step_trap = sparcnbsd_step_trap;
 254
 255   frame_unwind_append_sniffer (gdbarch, sparc64nbsd_sigtramp_frame_sniffer);
 256
 257   sparc64_init_abi (info, gdbarch);
 258
 259   /* NetBSD/sparc64 has SVR4-style shared libraries.  */
 260   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
 261   set_solib_svr4_fetch_link_map_offsets
 262     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 263 }
 264 \f
 265
 266 /* Provide a prototype to silence -Wmissing-prototypes.  */
 267 void _initialize_sparc64nbsd_tdep (void);
 268
 269 void
 270 _initialize_sparc64nbsd_tdep (void)
 271 {
 272   gdbarch_register_osabi (bfd_arch_sparc, bfd_mach_sparc_v9,
 273                           GDB_OSABI_NETBSD_ELF, sparc64nbsd_init_abi);
 274 }