gdb/sparc64nbsd-tdep.c

   1 /* Target-dependent code for NetBSD/sparc64.
   2
   3    Copyright (C) 2002-2012 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 3 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, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "defs.h"
  22 #include "frame.h"
  23 #include "frame-unwind.h"
  24 #include "gdbcore.h"
  25 #include "osabi.h"
  26 #include "regcache.h"
  27 #include "regset.h"
  28 #include "symtab.h"
  29 #include "objfiles.h"
  30 #include "solib-svr4.h"
  31 #include "trad-frame.h"
  32
  33 #include "gdb_assert.h"
  34 #include "gdb_string.h"
  35
  36 #include "sparc64-tdep.h"
  37 #include "nbsd-tdep.h"
  38
  39 /* From <machine/reg.h>.  */
  40 const struct sparc_gregset sparc64nbsd_gregset =
  41 {
  42   0 * 8,                        /* "tstate" */
  43   1 * 8,                        /* %pc */
  44   2 * 8,                        /* %npc */
  45   3 * 8,                        /* %y */
  46   -1,                           /* %fprs */
  47   -1,
  48   5 * 8,                        /* %g1 */
  49   -1,                           /* %l0 */
  50   4                             /* sizeof (%y) */
  51 };
  52 \f
  53
  54 static void
  55 sparc64nbsd_supply_gregset (const struct regset *regset,
  56                             struct regcache *regcache,
  57                             int regnum, const void *gregs, size_t len)
  58 {
  59   sparc64_supply_gregset (&sparc64nbsd_gregset, regcache, regnum, gregs);
  60 }
  61
  62 static void
  63 sparc64nbsd_supply_fpregset (const struct regset *regset,
  64                              struct regcache *regcache,
  65                              int regnum, const void *fpregs, size_t len)
  66 {
  67   sparc64_supply_fpregset (&sparc64_bsd_fpregset, regcache, regnum, fpregs);
  68 }
  69 \f
  70
  71 /* Signal trampolines.  */
  72
  73 /* The following variables describe the location of an on-stack signal
  74    trampoline.  The current values correspond to the memory layout for
  75    NetBSD 1.3 and up.  These shouldn't be necessary for NetBSD 2.0 and
  76    up, since NetBSD uses signal trampolines provided by libc now.  */
  77
  78 static const CORE_ADDR sparc64nbsd_sigtramp_start = 0xffffffffffffdee4ULL;
  79 static const CORE_ADDR sparc64nbsd_sigtramp_end = 0xffffffffffffe000ULL;
  80
  81 static int
  82 sparc64nbsd_pc_in_sigtramp (CORE_ADDR pc, const char *name)
  83 {
  84   if (pc >= sparc64nbsd_sigtramp_start && pc < sparc64nbsd_sigtramp_end)
  85     return 1;
  86
  87   return nbsd_pc_in_sigtramp (pc, name);
  88 }
  89
  90 struct trad_frame_saved_reg *
  91 sparc64nbsd_sigcontext_saved_regs (CORE_ADDR sigcontext_addr,
  92                                    struct frame_info *this_frame)
  93 {
  94   struct gdbarch *gdbarch = get_frame_arch (this_frame);
  95   struct trad_frame_saved_reg *saved_regs;
  96   CORE_ADDR addr, sp;
  97   int regnum, delta;
  98
  99   saved_regs = trad_frame_alloc_saved_regs (this_frame);
 100
 101   /* The registers are saved in bits and pieces scattered all over the
 102      place.  The code below records their location on the assumption
 103      that the part of the signal trampoline that saves the state has
 104      been executed.  */
 105
 106   saved_regs[SPARC_SP_REGNUM].addr = sigcontext_addr + 8;
 107   saved_regs[SPARC64_PC_REGNUM].addr = sigcontext_addr + 16;
 108   saved_regs[SPARC64_NPC_REGNUM].addr = sigcontext_addr + 24;
 109   saved_regs[SPARC64_STATE_REGNUM].addr = sigcontext_addr + 32;
 110   saved_regs[SPARC_G1_REGNUM].addr = sigcontext_addr + 40;
 111   saved_regs[SPARC_O0_REGNUM].addr = sigcontext_addr + 48;
 112
 113   /* The remaining `global' registers and %y are saved in the `local'
 114      registers.  */
 115   delta = SPARC_L0_REGNUM - SPARC_G0_REGNUM;
 116   for (regnum = SPARC_G2_REGNUM; regnum <= SPARC_G7_REGNUM; regnum++)
 117     saved_regs[regnum].realreg = regnum + delta;
 118   saved_regs[SPARC64_Y_REGNUM].realreg = SPARC_L1_REGNUM;
 119
 120   /* The remaining `out' registers can be found in the current frame's
 121      `in' registers.  */
 122   delta = SPARC_I0_REGNUM - SPARC_O0_REGNUM;
 123   for (regnum = SPARC_O1_REGNUM; regnum <= SPARC_O5_REGNUM; regnum++)
 124     saved_regs[regnum].realreg = regnum + delta;
 125   saved_regs[SPARC_O7_REGNUM].realreg = SPARC_I7_REGNUM;
 126
 127   /* The `local' and `in' registers have been saved in the register
 128      save area.  */
 129   addr = saved_regs[SPARC_SP_REGNUM].addr;
 130   sp = get_frame_memory_unsigned (this_frame, addr, 8);
 131   for (regnum = SPARC_L0_REGNUM, addr = sp + BIAS;
 132        regnum <= SPARC_I7_REGNUM; regnum++, addr += 8)
 133     saved_regs[regnum].addr = addr;
 134
 135   /* Handle StackGhost.  */
 136   {
 137     ULONGEST wcookie = sparc_fetch_wcookie (gdbarch);
 138
 139     if (wcookie != 0)
 140       {
 141         ULONGEST i7;
 142
 143         addr = saved_regs[SPARC_I7_REGNUM].addr;
 144         i7 = get_frame_memory_unsigned (this_frame, addr, 8);
 145         trad_frame_set_value (saved_regs, SPARC_I7_REGNUM, i7 ^ wcookie);
 146       }
 147   }
 148
 149   /* TODO: Handle the floating-point registers.  */
 150
 151   return saved_regs;
 152 }
 153
 154 static struct sparc_frame_cache *
 155 sparc64nbsd_sigcontext_frame_cache (struct frame_info *this_frame,
 156                                     void **this_cache)
 157 {
 158   struct sparc_frame_cache *cache;
 159   CORE_ADDR addr;
 160
 161   if (*this_cache)
 162     return *this_cache;
 163
 164   cache = sparc_frame_cache (this_frame, this_cache);
 165   gdb_assert (cache == *this_cache);
 166
 167   /* If we couldn't find the frame's function, we're probably dealing
 168      with an on-stack signal trampoline.  */
 169   if (cache->pc == 0)
 170     {
 171       cache->pc = sparc64nbsd_sigtramp_start;
 172
 173       /* Since we couldn't find the frame's function, the cache was
 174          initialized under the assumption that we're frameless.  */
 175       sparc_record_save_insn (cache);
 176       addr = get_frame_register_unsigned (this_frame, SPARC_FP_REGNUM);
 177       if (addr & 1)
 178         addr += BIAS;
 179       cache->base = addr;
 180     }
 181
 182   /* We find the appropriate instance of `struct sigcontext' at a
 183      fixed offset in the signal frame.  */
 184   addr = cache->base + 128 + 8;
 185   cache->saved_regs = sparc64nbsd_sigcontext_saved_regs (addr, this_frame);
 186
 187   return cache;
 188 }
 189
 190 static void
 191 sparc64nbsd_sigcontext_frame_this_id (struct frame_info *this_frame,
 192                                       void **this_cache,
 193                                       struct frame_id *this_id)
 194 {
 195   struct sparc_frame_cache *cache =
 196     sparc64nbsd_sigcontext_frame_cache (this_frame, this_cache);
 197
 198   (*this_id) = frame_id_build (cache->base, cache->pc);
 199 }
 200
 201 static struct value *
 202 sparc64nbsd_sigcontext_frame_prev_register (struct frame_info *this_frame,
 203                                             void **this_cache, int regnum)
 204 {
 205   struct sparc_frame_cache *cache =
 206     sparc64nbsd_sigcontext_frame_cache (this_frame, this_cache);
 207
 208   return trad_frame_get_prev_register (this_frame, cache->saved_regs, regnum);
 209 }
 210
 211 static int
 212 sparc64nbsd_sigtramp_frame_sniffer (const struct frame_unwind *self,
 213                                     struct frame_info *this_frame,
 214                                     void **this_cache)
 215 {
 216   CORE_ADDR pc = get_frame_pc (this_frame);
 217   const char *name;
 218
 219   find_pc_partial_function (pc, &name, NULL, NULL);
 220   if (sparc64nbsd_pc_in_sigtramp (pc, name))
 221     {
 222       if (name == NULL || strncmp (name, "__sigtramp_sigcontext", 21))
 223         return 1;
 224     }
 225
 226   return 0;
 227 }
 228
 229 static const struct frame_unwind sparc64nbsd_sigcontext_frame_unwind =
 230 {
 231   SIGTRAMP_FRAME,
 232   default_frame_unwind_stop_reason,
 233   sparc64nbsd_sigcontext_frame_this_id,
 234   sparc64nbsd_sigcontext_frame_prev_register,
 235   NULL,
 236   sparc64nbsd_sigtramp_frame_sniffer
 237 };
 238 \f
 239
 240 static void
 241 sparc64nbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 242 {
 243   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 244
 245   tdep->gregset = regset_alloc (gdbarch, sparc64nbsd_supply_gregset, NULL);
 246   tdep->sizeof_gregset = 160;
 247
 248   tdep->fpregset = regset_alloc (gdbarch, sparc64nbsd_supply_fpregset, NULL);
 249   tdep->sizeof_fpregset = 272;
 250
 251   /* Make sure we can single-step "new" syscalls.  */
 252   tdep->step_trap = sparcnbsd_step_trap;
 253
 254   frame_unwind_append_unwinder (gdbarch, &sparc64nbsd_sigcontext_frame_unwind);
 255
 256   sparc64_init_abi (info, gdbarch);
 257
 258   /* NetBSD/sparc64 has SVR4-style shared libraries.  */
 259   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
 260   set_solib_svr4_fetch_link_map_offsets
 261     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 262 }
 263 \f
 264
 265 /* Provide a prototype to silence -Wmissing-prototypes.  */
 266 void _initialize_sparc64nbsd_tdep (void);
 267
 268 void
 269 _initialize_sparc64nbsd_tdep (void)
 270 {
 271   gdbarch_register_osabi (bfd_arch_sparc, bfd_mach_sparc_v9,
 272                           GDB_OSABI_NETBSD_ELF, sparc64nbsd_init_abi);
 273 }