gdb/sparc64nbsd-tdep.c

   1 /* Target-dependent code for NetBSD/sparc64.
   2
   3    Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
   4    Free Software Foundation, Inc.
   5    Based on code contributed by Wasabi Systems, Inc.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #include "defs.h"
  23 #include "frame.h"
  24 #include "frame-unwind.h"
  25 #include "gdbcore.h"
  26 #include "osabi.h"
  27 #include "regcache.h"
  28 #include "regset.h"
  29 #include "symtab.h"
  30 #include "objfiles.h"
  31 #include "solib-svr4.h"
  32 #include "trad-frame.h"
  33
  34 #include "gdb_assert.h"
  35 #include "gdb_string.h"
  36
  37 #include "sparc64-tdep.h"
  38 #include "nbsd-tdep.h"
  39
  40 /* From <machine/reg.h>.  */
  41 const struct sparc_gregset sparc64nbsd_gregset =
  42 {
  43   0 * 8,                        /* "tstate" */
  44   1 * 8,                        /* %pc */
  45   2 * 8,                        /* %npc */
  46   3 * 8,                        /* %y */
  47   -1,                           /* %fprs */
  48   -1,
  49   5 * 8,                        /* %g1 */
  50   -1,                           /* %l0 */
  51   4                             /* sizeof (%y) */
  52 };
  53 \f
  54
  55 static void
  56 sparc64nbsd_supply_gregset (const struct regset *regset,
  57                             struct regcache *regcache,
  58                             int regnum, const void *gregs, size_t len)
  59 {
  60   sparc64_supply_gregset (&sparc64nbsd_gregset, regcache, regnum, gregs);
  61 }
  62
  63 static void
  64 sparc64nbsd_supply_fpregset (const struct regset *regset,
  65                              struct regcache *regcache,
  66                              int regnum, const void *fpregs, size_t len)
  67 {
  68   sparc64_supply_fpregset (regcache, regnum, fpregs);
  69 }
  70 \f
  71
  72 /* Signal trampolines.  */
  73
  74 /* The following variables describe the location of an on-stack signal
  75    trampoline.  The current values correspond to the memory layout for
  76    NetBSD 1.3 and up.  These shouldn't be necessary for NetBSD 2.0 and
  77    up, since NetBSD uses signal trampolines provided by libc now.  */
  78
  79 static const CORE_ADDR sparc64nbsd_sigtramp_start = 0xffffffffffffdee4ULL;
  80 static const CORE_ADDR sparc64nbsd_sigtramp_end = 0xffffffffffffe000ULL;
  81
  82 static int
  83 sparc64nbsd_pc_in_sigtramp (CORE_ADDR pc, char *name)
  84 {
  85   if (pc >= sparc64nbsd_sigtramp_start && pc < sparc64nbsd_sigtramp_end)
  86     return 1;
  87
  88   return nbsd_pc_in_sigtramp (pc, name);
  89 }
  90
  91 struct trad_frame_saved_reg *
  92 sparc64nbsd_sigcontext_saved_regs (CORE_ADDR sigcontext_addr,
  93                                    struct frame_info *this_frame)
  94 {
  95   struct gdbarch *gdbarch = get_frame_arch (this_frame);
  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 (this_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 (this_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 (gdbarch);
 139
 140     if (wcookie != 0)
 141       {
 142         ULONGEST i7;
 143
 144         addr = saved_regs[SPARC_I7_REGNUM].addr;
 145         i7 = get_frame_memory_unsigned (this_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 *this_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 (this_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 = get_frame_register_unsigned (this_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, this_frame);
 187
 188   return cache;
 189 }
 190
 191 static void
 192 sparc64nbsd_sigcontext_frame_this_id (struct frame_info *this_frame,
 193                                       void **this_cache,
 194                                       struct frame_id *this_id)
 195 {
 196   struct sparc_frame_cache *cache =
 197     sparc64nbsd_sigcontext_frame_cache (this_frame, this_cache);
 198
 199   (*this_id) = frame_id_build (cache->base, cache->pc);
 200 }
 201
 202 static struct value *
 203 sparc64nbsd_sigcontext_frame_prev_register (struct frame_info *this_frame,
 204                                             void **this_cache, int regnum)
 205 {
 206   struct sparc_frame_cache *cache =
 207     sparc64nbsd_sigcontext_frame_cache (this_frame, this_cache);
 208
 209   return trad_frame_get_prev_register (this_frame, cache->saved_regs, regnum);
 210 }
 211
 212 static int
 213 sparc64nbsd_sigtramp_frame_sniffer (const struct frame_unwind *self,
 214                                     struct frame_info *this_frame,
 215                                     void **this_cache)
 216 {
 217   CORE_ADDR pc = get_frame_pc (this_frame);
 218   char *name;
 219
 220   find_pc_partial_function (pc, &name, NULL, NULL);
 221   if (sparc64nbsd_pc_in_sigtramp (pc, name))
 222     {
 223       if (name == NULL || strncmp (name, "__sigtramp_sigcontext", 21))
 224         return 1;
 225     }
 226
 227   return 0;
 228 }
 229
 230 static const struct frame_unwind sparc64nbsd_sigcontext_frame_unwind =
 231 {
 232   SIGTRAMP_FRAME,
 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 }