gdb/sparc64-netbsd-tdep.c

   1 /* Target-dependent code for NetBSD/sparc64.
   2
   3    Copyright (C) 2002-2024 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 "frame.h"
  22 #include "frame-unwind.h"
  23 #include "gdbcore.h"
  24 #include "osabi.h"
  25 #include "regcache.h"
  26 #include "regset.h"
  27 #include "symtab.h"
  28 #include "objfiles.h"
  29 #include "solib-svr4.h"
  30 #include "trad-frame.h"
  31
  32 #include "sparc64-tdep.h"
  33 #include "netbsd-tdep.h"
  34
  35 /* From <machine/reg.h>.  */
  36 const struct sparc_gregmap sparc64nbsd_gregmap =
  37 {
  38   0 * 8,                        /* "tstate" */
  39   1 * 8,                        /* %pc */
  40   2 * 8,                        /* %npc */
  41   3 * 8,                        /* %y */
  42   -1,                           /* %fprs */
  43   -1,
  44   5 * 8,                        /* %g1 */
  45   -1,                           /* %l0 */
  46   4                             /* sizeof (%y) */
  47 };
  48 \f
  49
  50 static void
  51 sparc64nbsd_supply_gregset (const struct regset *regset,
  52                             struct regcache *regcache,
  53                             int regnum, const void *gregs, size_t len)
  54 {
  55   sparc64_supply_gregset (&sparc64nbsd_gregmap, regcache, regnum, gregs);
  56 }
  57
  58 static void
  59 sparc64nbsd_supply_fpregset (const struct regset *regset,
  60                              struct regcache *regcache,
  61                              int regnum, const void *fpregs, size_t len)
  62 {
  63   sparc64_supply_fpregset (&sparc64_bsd_fpregmap, regcache, regnum, fpregs);
  64 }
  65 \f
  66
  67 /* Signal trampolines.  */
  68
  69 /* The following variables describe the location of an on-stack signal
  70    trampoline.  The current values correspond to the memory layout for
  71    NetBSD 1.3 and up.  These shouldn't be necessary for NetBSD 2.0 and
  72    up, since NetBSD uses signal trampolines provided by libc now.  */
  73
  74 static const CORE_ADDR sparc64nbsd_sigtramp_start = 0xffffffffffffdee4ULL;
  75 static const CORE_ADDR sparc64nbsd_sigtramp_end = 0xffffffffffffe000ULL;
  76
  77 static int
  78 sparc64nbsd_pc_in_sigtramp (CORE_ADDR pc, const char *name)
  79 {
  80   if (pc >= sparc64nbsd_sigtramp_start && pc < sparc64nbsd_sigtramp_end)
  81     return 1;
  82
  83   return nbsd_pc_in_sigtramp (pc, name);
  84 }
  85
  86 trad_frame_saved_reg *
  87 sparc64nbsd_sigcontext_saved_regs (CORE_ADDR sigcontext_addr,
  88                                    const frame_info_ptr &this_frame)
  89 {
  90   struct gdbarch *gdbarch = get_frame_arch (this_frame);
  91   trad_frame_saved_reg *saved_regs;
  92   CORE_ADDR addr, sp;
  93   int regnum, delta;
  94
  95   saved_regs = trad_frame_alloc_saved_regs (this_frame);
  96
  97   /* The registers are saved in bits and pieces scattered all over the
  98      place.  The code below records their location on the assumption
  99      that the part of the signal trampoline that saves the state has
 100      been executed.  */
 101
 102   saved_regs[SPARC_SP_REGNUM].set_addr (sigcontext_addr + 8);
 103   saved_regs[SPARC64_PC_REGNUM].set_addr (sigcontext_addr + 16);
 104   saved_regs[SPARC64_NPC_REGNUM].set_addr (sigcontext_addr + 24);
 105   saved_regs[SPARC64_STATE_REGNUM].set_addr (sigcontext_addr + 32);
 106   saved_regs[SPARC_G1_REGNUM].set_addr (sigcontext_addr + 40);
 107   saved_regs[SPARC_O0_REGNUM].set_addr (sigcontext_addr + 48);
 108
 109   /* The remaining `global' registers and %y are saved in the `local'
 110      registers.  */
 111   delta = SPARC_L0_REGNUM - SPARC_G0_REGNUM;
 112   for (regnum = SPARC_G2_REGNUM; regnum <= SPARC_G7_REGNUM; regnum++)
 113     saved_regs[regnum].set_realreg (regnum + delta);
 114   saved_regs[SPARC64_Y_REGNUM].set_realreg (SPARC_L1_REGNUM);
 115
 116   /* The remaining `out' registers can be found in the current frame's
 117      `in' registers.  */
 118   delta = SPARC_I0_REGNUM - SPARC_O0_REGNUM;
 119   for (regnum = SPARC_O1_REGNUM; regnum <= SPARC_O5_REGNUM; regnum++)
 120     saved_regs[regnum].set_realreg (regnum + delta);
 121   saved_regs[SPARC_O7_REGNUM].set_realreg (SPARC_I7_REGNUM);
 122
 123   /* The `local' and `in' registers have been saved in the register
 124      save area.  */
 125   addr = saved_regs[SPARC_SP_REGNUM].addr ();
 126   sp = get_frame_memory_unsigned (this_frame, addr, 8);
 127   for (regnum = SPARC_L0_REGNUM, addr = sp + BIAS;
 128        regnum <= SPARC_I7_REGNUM; regnum++, addr += 8)
 129     saved_regs[regnum].set_addr (addr);
 130
 131   /* Handle StackGhost.  */
 132   {
 133     ULONGEST wcookie = sparc_fetch_wcookie (gdbarch);
 134
 135     if (wcookie != 0)
 136       {
 137         ULONGEST i7;
 138
 139         addr = saved_regs[SPARC_I7_REGNUM].addr ();
 140         i7 = get_frame_memory_unsigned (this_frame, addr, 8);
 141         saved_regs[SPARC_I7_REGNUM].set_value (i7 ^ wcookie);
 142       }
 143   }
 144
 145   /* TODO: Handle the floating-point registers.  */
 146
 147   return saved_regs;
 148 }
 149
 150 static struct sparc_frame_cache *
 151 sparc64nbsd_sigcontext_frame_cache (const frame_info_ptr &this_frame,
 152                                     void **this_cache)
 153 {
 154   struct sparc_frame_cache *cache;
 155   CORE_ADDR addr;
 156
 157   if (*this_cache)
 158     return (struct sparc_frame_cache *) *this_cache;
 159
 160   cache = sparc_frame_cache (this_frame, this_cache);
 161   gdb_assert (cache == *this_cache);
 162
 163   /* If we couldn't find the frame's function, we're probably dealing
 164      with an on-stack signal trampoline.  */
 165   if (cache->pc == 0)
 166     {
 167       cache->pc = sparc64nbsd_sigtramp_start;
 168
 169       /* Since we couldn't find the frame's function, the cache was
 170          initialized under the assumption that we're frameless.  */
 171       sparc_record_save_insn (cache);
 172       addr = get_frame_register_unsigned (this_frame, SPARC_FP_REGNUM);
 173       if (addr & 1)
 174         addr += BIAS;
 175       cache->base = addr;
 176     }
 177
 178   /* We find the appropriate instance of `struct sigcontext' at a
 179      fixed offset in the signal frame.  */
 180   addr = cache->base + 128 + 8;
 181   cache->saved_regs = sparc64nbsd_sigcontext_saved_regs (addr, this_frame);
 182
 183   return cache;
 184 }
 185
 186 static void
 187 sparc64nbsd_sigcontext_frame_this_id (const frame_info_ptr &this_frame,
 188                                       void **this_cache,
 189                                       struct frame_id *this_id)
 190 {
 191   struct sparc_frame_cache *cache =
 192     sparc64nbsd_sigcontext_frame_cache (this_frame, this_cache);
 193
 194   (*this_id) = frame_id_build (cache->base, cache->pc);
 195 }
 196
 197 static struct value *
 198 sparc64nbsd_sigcontext_frame_prev_register (const frame_info_ptr &this_frame,
 199                                             void **this_cache, int regnum)
 200 {
 201   struct sparc_frame_cache *cache =
 202     sparc64nbsd_sigcontext_frame_cache (this_frame, this_cache);
 203
 204   return trad_frame_get_prev_register (this_frame, cache->saved_regs, regnum);
 205 }
 206
 207 static int
 208 sparc64nbsd_sigtramp_frame_sniffer (const struct frame_unwind *self,
 209                                     const frame_info_ptr &this_frame,
 210                                     void **this_cache)
 211 {
 212   CORE_ADDR pc = get_frame_pc (this_frame);
 213   const char *name;
 214
 215   find_pc_partial_function (pc, &name, NULL, NULL);
 216   if (sparc64nbsd_pc_in_sigtramp (pc, name))
 217     {
 218       if (name == NULL || !startswith (name, "__sigtramp_sigcontext"))
 219         return 1;
 220     }
 221
 222   return 0;
 223 }
 224
 225 static const struct frame_unwind sparc64nbsd_sigcontext_frame_unwind =
 226 {
 227   "sparc64 netbsd sigcontext",
 228   SIGTRAMP_FRAME,
 229   default_frame_unwind_stop_reason,
 230   sparc64nbsd_sigcontext_frame_this_id,
 231   sparc64nbsd_sigcontext_frame_prev_register,
 232   NULL,
 233   sparc64nbsd_sigtramp_frame_sniffer
 234 };
 235 \f
 236
 237 static const struct regset sparc64nbsd_gregset =
 238   {
 239     NULL, sparc64nbsd_supply_gregset, NULL
 240   };
 241
 242 static const struct regset sparc64nbsd_fpregset =
 243   {
 244     NULL, sparc64nbsd_supply_fpregset, NULL
 245   };
 246
 247 static void
 248 sparc64nbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 249 {
 250   sparc_gdbarch_tdep *tdep = gdbarch_tdep<sparc_gdbarch_tdep> (gdbarch);
 251
 252   nbsd_init_abi (info, gdbarch);
 253
 254   tdep->gregset = &sparc64nbsd_gregset;
 255   tdep->sizeof_gregset = 160;
 256
 257   tdep->fpregset =  &sparc64nbsd_fpregset;
 258   tdep->sizeof_fpregset = 272;
 259
 260   /* Make sure we can single-step "new" syscalls.  */
 261   tdep->step_trap = sparcnbsd_step_trap;
 262
 263   frame_unwind_append_unwinder (gdbarch, &sparc64nbsd_sigcontext_frame_unwind);
 264
 265   sparc64_init_abi (info, gdbarch);
 266
 267   /* NetBSD/sparc64 has SVR4-style shared libraries.  */
 268   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
 269   set_solib_svr4_fetch_link_map_offsets
 270     (gdbarch, svr4_lp64_fetch_link_map_offsets);
 271 }
 272
 273 void _initialize_sparc64nbsd_tdep ();
 274 void
 275 _initialize_sparc64nbsd_tdep ()
 276 {
 277   gdbarch_register_osabi (bfd_arch_sparc, bfd_mach_sparc_v9,
 278                           GDB_OSABI_NETBSD, sparc64nbsd_init_abi);
 279 }