| 1 | /* Target-dependent code for NetBSD/sparc. |
| 2 | |
| 3 | Copyright (C) 2002, 2003, 2004, 2006, 2007, 2008 |
| 4 | Free Software Foundation, Inc. |
| 5 | 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 "gdbtypes.h" |
| 27 | #include "osabi.h" |
| 28 | #include "regcache.h" |
| 29 | #include "regset.h" |
| 30 | #include "solib-svr4.h" |
| 31 | #include "symtab.h" |
| 32 | #include "trad-frame.h" |
| 33 | |
| 34 | #include "gdb_assert.h" |
| 35 | #include "gdb_string.h" |
| 36 | |
| 37 | #include "sparc-tdep.h" |
| 38 | #include "nbsd-tdep.h" |
| 39 | |
| 40 | /* Macros to extract fields from SPARC instructions. */ |
| 41 | #define X_RS1(i) (((i) >> 14) & 0x1f) |
| 42 | #define X_RS2(i) ((i) & 0x1f) |
| 43 | #define X_I(i) (((i) >> 13) & 1) |
| 44 | |
| 45 | const struct sparc_gregset sparc32nbsd_gregset = |
| 46 | { |
| 47 | 0 * 4, /* %psr */ |
| 48 | 1 * 4, /* %pc */ |
| 49 | 2 * 4, /* %npc */ |
| 50 | 3 * 4, /* %y */ |
| 51 | -1, /* %wim */ |
| 52 | -1, /* %tbr */ |
| 53 | 5 * 4, /* %g1 */ |
| 54 | -1 /* %l0 */ |
| 55 | }; |
| 56 | |
| 57 | static void |
| 58 | sparc32nbsd_supply_gregset (const struct regset *regset, |
| 59 | struct regcache *regcache, |
| 60 | int regnum, const void *gregs, size_t len) |
| 61 | { |
| 62 | sparc32_supply_gregset (&sparc32nbsd_gregset, regcache, regnum, gregs); |
| 63 | |
| 64 | /* Traditional NetBSD core files don't use multiple register sets. |
| 65 | Instead, the general-purpose and floating-point registers are |
| 66 | lumped together in a single section. */ |
| 67 | if (len >= 212) |
| 68 | sparc32_supply_fpregset (regcache, regnum, (const char *) gregs + 80); |
| 69 | } |
| 70 | |
| 71 | static void |
| 72 | sparc32nbsd_supply_fpregset (const struct regset *regset, |
| 73 | struct regcache *regcache, |
| 74 | int regnum, const void *fpregs, size_t len) |
| 75 | { |
| 76 | sparc32_supply_fpregset (regcache, regnum, fpregs); |
| 77 | } |
| 78 | |
| 79 | \f |
| 80 | /* Signal trampolines. */ |
| 81 | |
| 82 | /* The following variables describe the location of an on-stack signal |
| 83 | trampoline. The current values correspond to the memory layout for |
| 84 | NetBSD 1.3 and up. These shouldn't be necessary for NetBSD 2.0 and |
| 85 | up, since NetBSD uses signal trampolines provided by libc now. */ |
| 86 | |
| 87 | static const CORE_ADDR sparc32nbsd_sigtramp_start = 0xeffffef0; |
| 88 | static const CORE_ADDR sparc32nbsd_sigtramp_end = 0xeffffff0; |
| 89 | |
| 90 | static int |
| 91 | sparc32nbsd_pc_in_sigtramp (CORE_ADDR pc, char *name) |
| 92 | { |
| 93 | if (pc >= sparc32nbsd_sigtramp_start && pc < sparc32nbsd_sigtramp_end) |
| 94 | return 1; |
| 95 | |
| 96 | return nbsd_pc_in_sigtramp (pc, name); |
| 97 | } |
| 98 | |
| 99 | struct trad_frame_saved_reg * |
| 100 | sparc32nbsd_sigcontext_saved_regs (struct frame_info *next_frame) |
| 101 | { |
| 102 | struct trad_frame_saved_reg *saved_regs; |
| 103 | CORE_ADDR addr, sigcontext_addr; |
| 104 | int regnum, delta; |
| 105 | ULONGEST psr; |
| 106 | |
| 107 | saved_regs = trad_frame_alloc_saved_regs (next_frame); |
| 108 | |
| 109 | /* We find the appropriate instance of `struct sigcontext' at a |
| 110 | fixed offset in the signal frame. */ |
| 111 | addr = frame_unwind_register_unsigned (next_frame, SPARC_FP_REGNUM); |
| 112 | sigcontext_addr = addr + 64 + 16; |
| 113 | |
| 114 | /* The registers are saved in bits and pieces scattered all over the |
| 115 | place. The code below records their location on the assumption |
| 116 | that the part of the signal trampoline that saves the state has |
| 117 | been executed. */ |
| 118 | |
| 119 | saved_regs[SPARC_SP_REGNUM].addr = sigcontext_addr + 8; |
| 120 | saved_regs[SPARC32_PC_REGNUM].addr = sigcontext_addr + 12; |
| 121 | saved_regs[SPARC32_NPC_REGNUM].addr = sigcontext_addr + 16; |
| 122 | saved_regs[SPARC32_PSR_REGNUM].addr = sigcontext_addr + 20; |
| 123 | saved_regs[SPARC_G1_REGNUM].addr = sigcontext_addr + 24; |
| 124 | saved_regs[SPARC_O0_REGNUM].addr = sigcontext_addr + 28; |
| 125 | |
| 126 | /* The remaining `global' registers and %y are saved in the `local' |
| 127 | registers. */ |
| 128 | delta = SPARC_L0_REGNUM - SPARC_G0_REGNUM; |
| 129 | for (regnum = SPARC_G2_REGNUM; regnum <= SPARC_G7_REGNUM; regnum++) |
| 130 | saved_regs[regnum].realreg = regnum + delta; |
| 131 | saved_regs[SPARC32_Y_REGNUM].realreg = SPARC_L1_REGNUM; |
| 132 | |
| 133 | /* The remaining `out' registers can be found in the current frame's |
| 134 | `in' registers. */ |
| 135 | delta = SPARC_I0_REGNUM - SPARC_O0_REGNUM; |
| 136 | for (regnum = SPARC_O1_REGNUM; regnum <= SPARC_O5_REGNUM; regnum++) |
| 137 | saved_regs[regnum].realreg = regnum + delta; |
| 138 | saved_regs[SPARC_O7_REGNUM].realreg = SPARC_I7_REGNUM; |
| 139 | |
| 140 | /* The `local' and `in' registers have been saved in the register |
| 141 | save area. */ |
| 142 | addr = saved_regs[SPARC_SP_REGNUM].addr; |
| 143 | addr = get_frame_memory_unsigned (next_frame, addr, 4); |
| 144 | for (regnum = SPARC_L0_REGNUM; |
| 145 | regnum <= SPARC_I7_REGNUM; regnum++, addr += 4) |
| 146 | saved_regs[regnum].addr = addr; |
| 147 | |
| 148 | /* Handle StackGhost. */ |
| 149 | { |
| 150 | ULONGEST wcookie = sparc_fetch_wcookie (); |
| 151 | |
| 152 | if (wcookie != 0) |
| 153 | { |
| 154 | ULONGEST i7; |
| 155 | |
| 156 | addr = saved_regs[SPARC_I7_REGNUM].addr; |
| 157 | i7 = get_frame_memory_unsigned (next_frame, addr, 4); |
| 158 | trad_frame_set_value (saved_regs, SPARC_I7_REGNUM, i7 ^ wcookie); |
| 159 | } |
| 160 | } |
| 161 | |
| 162 | /* The floating-point registers are only saved if the EF bit in %prs |
| 163 | has been set. */ |
| 164 | |
| 165 | #define PSR_EF 0x00001000 |
| 166 | |
| 167 | addr = saved_regs[SPARC32_PSR_REGNUM].addr; |
| 168 | psr = get_frame_memory_unsigned (next_frame, addr, 4); |
| 169 | if (psr & PSR_EF) |
| 170 | { |
| 171 | CORE_ADDR sp; |
| 172 | |
| 173 | sp = frame_unwind_register_unsigned (next_frame, SPARC_SP_REGNUM); |
| 174 | saved_regs[SPARC32_FSR_REGNUM].addr = sp + 96; |
| 175 | for (regnum = SPARC_F0_REGNUM, addr = sp + 96 + 8; |
| 176 | regnum <= SPARC_F31_REGNUM; regnum++, addr += 4) |
| 177 | saved_regs[regnum].addr = addr; |
| 178 | } |
| 179 | |
| 180 | return saved_regs; |
| 181 | } |
| 182 | |
| 183 | static struct sparc_frame_cache * |
| 184 | sparc32nbsd_sigcontext_frame_cache (struct frame_info *next_frame, |
| 185 | void **this_cache) |
| 186 | { |
| 187 | struct sparc_frame_cache *cache; |
| 188 | CORE_ADDR addr; |
| 189 | |
| 190 | if (*this_cache) |
| 191 | return *this_cache; |
| 192 | |
| 193 | cache = sparc_frame_cache (next_frame, this_cache); |
| 194 | gdb_assert (cache == *this_cache); |
| 195 | |
| 196 | /* If we couldn't find the frame's function, we're probably dealing |
| 197 | with an on-stack signal trampoline. */ |
| 198 | if (cache->pc == 0) |
| 199 | { |
| 200 | cache->pc = sparc32nbsd_sigtramp_start; |
| 201 | |
| 202 | /* Since we couldn't find the frame's function, the cache was |
| 203 | initialized under the assumption that we're frameless. */ |
| 204 | cache->frameless_p = 0; |
| 205 | addr = frame_unwind_register_unsigned (next_frame, SPARC_FP_REGNUM); |
| 206 | cache->base = addr; |
| 207 | } |
| 208 | |
| 209 | cache->saved_regs = sparc32nbsd_sigcontext_saved_regs (next_frame); |
| 210 | |
| 211 | return cache; |
| 212 | } |
| 213 | |
| 214 | static void |
| 215 | sparc32nbsd_sigcontext_frame_this_id (struct frame_info *next_frame, |
| 216 | void **this_cache, |
| 217 | struct frame_id *this_id) |
| 218 | { |
| 219 | struct sparc_frame_cache *cache = |
| 220 | sparc32nbsd_sigcontext_frame_cache (next_frame, this_cache); |
| 221 | |
| 222 | (*this_id) = frame_id_build (cache->base, cache->pc); |
| 223 | } |
| 224 | |
| 225 | static void |
| 226 | sparc32nbsd_sigcontext_frame_prev_register (struct frame_info *next_frame, |
| 227 | void **this_cache, |
| 228 | int regnum, int *optimizedp, |
| 229 | enum lval_type *lvalp, |
| 230 | CORE_ADDR *addrp, |
| 231 | int *realnump, gdb_byte *valuep) |
| 232 | { |
| 233 | struct sparc_frame_cache *cache = |
| 234 | sparc32nbsd_sigcontext_frame_cache (next_frame, this_cache); |
| 235 | |
| 236 | trad_frame_get_prev_register (next_frame, cache->saved_regs, regnum, |
| 237 | optimizedp, lvalp, addrp, realnump, valuep); |
| 238 | } |
| 239 | |
| 240 | static const struct frame_unwind sparc32nbsd_sigcontext_frame_unwind = |
| 241 | { |
| 242 | SIGTRAMP_FRAME, |
| 243 | sparc32nbsd_sigcontext_frame_this_id, |
| 244 | sparc32nbsd_sigcontext_frame_prev_register |
| 245 | }; |
| 246 | |
| 247 | static const struct frame_unwind * |
| 248 | sparc32nbsd_sigtramp_frame_sniffer (struct frame_info *next_frame) |
| 249 | { |
| 250 | CORE_ADDR pc = frame_pc_unwind (next_frame); |
| 251 | char *name; |
| 252 | |
| 253 | find_pc_partial_function (pc, &name, NULL, NULL); |
| 254 | if (sparc32nbsd_pc_in_sigtramp (pc, name)) |
| 255 | { |
| 256 | if (name == NULL || strncmp (name, "__sigtramp_sigcontext", 21)) |
| 257 | return &sparc32nbsd_sigcontext_frame_unwind; |
| 258 | } |
| 259 | |
| 260 | return NULL; |
| 261 | } |
| 262 | \f |
| 263 | /* Return the address of a system call's alternative return |
| 264 | address. */ |
| 265 | |
| 266 | CORE_ADDR |
| 267 | sparcnbsd_step_trap (struct frame_info *frame, unsigned long insn) |
| 268 | { |
| 269 | if ((X_I (insn) == 0 && X_RS1 (insn) == 0 && X_RS2 (insn) == 0) |
| 270 | || (X_I (insn) == 1 && X_RS1 (insn) == 0 && (insn & 0x7f) == 0)) |
| 271 | { |
| 272 | /* "New" system call. */ |
| 273 | ULONGEST number = get_frame_register_unsigned (frame, SPARC_G1_REGNUM); |
| 274 | |
| 275 | if (number & 0x400) |
| 276 | return get_frame_register_unsigned (frame, SPARC_G2_REGNUM); |
| 277 | if (number & 0x800) |
| 278 | return get_frame_register_unsigned (frame, SPARC_G7_REGNUM); |
| 279 | } |
| 280 | |
| 281 | return 0; |
| 282 | } |
| 283 | \f |
| 284 | |
| 285 | static void |
| 286 | sparc32nbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 287 | { |
| 288 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 289 | |
| 290 | /* NetBSD doesn't support the 128-bit `long double' from the psABI. */ |
| 291 | set_gdbarch_long_double_bit (gdbarch, 64); |
| 292 | set_gdbarch_long_double_format (gdbarch, floatformats_ieee_double); |
| 293 | |
| 294 | tdep->gregset = regset_alloc (gdbarch, sparc32nbsd_supply_gregset, NULL); |
| 295 | tdep->sizeof_gregset = 20 * 4; |
| 296 | |
| 297 | tdep->fpregset = regset_alloc (gdbarch, sparc32nbsd_supply_fpregset, NULL); |
| 298 | tdep->sizeof_fpregset = 33 * 4; |
| 299 | |
| 300 | /* Make sure we can single-step "new" syscalls. */ |
| 301 | tdep->step_trap = sparcnbsd_step_trap; |
| 302 | |
| 303 | frame_unwind_append_sniffer (gdbarch, sparc32nbsd_sigtramp_frame_sniffer); |
| 304 | } |
| 305 | |
| 306 | static void |
| 307 | sparc32nbsd_aout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 308 | { |
| 309 | sparc32nbsd_init_abi (info, gdbarch); |
| 310 | } |
| 311 | |
| 312 | void |
| 313 | sparc32nbsd_elf_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 314 | { |
| 315 | sparc32nbsd_init_abi (info, gdbarch); |
| 316 | |
| 317 | set_solib_svr4_fetch_link_map_offsets |
| 318 | (gdbarch, svr4_ilp32_fetch_link_map_offsets); |
| 319 | } |
| 320 | |
| 321 | static enum gdb_osabi |
| 322 | sparcnbsd_aout_osabi_sniffer (bfd *abfd) |
| 323 | { |
| 324 | if (strcmp (bfd_get_target (abfd), "a.out-sparc-netbsd") == 0) |
| 325 | return GDB_OSABI_NETBSD_AOUT; |
| 326 | |
| 327 | return GDB_OSABI_UNKNOWN; |
| 328 | } |
| 329 | |
| 330 | /* OpenBSD uses the traditional NetBSD core file format, even for |
| 331 | ports that use ELF. Therefore, if the default OS ABI is OpenBSD |
| 332 | ELF, we return that instead of NetBSD a.out. This is mainly for |
| 333 | the benfit of OpenBSD/sparc64, which inherits the sniffer below |
| 334 | since we include this file for an OpenBSD/sparc64 target. For |
| 335 | OpenBSD/sparc, the NetBSD a.out OS ABI is probably similar enough |
| 336 | to both the OpenBSD a.out and the OpenBSD ELF OS ABI. */ |
| 337 | #if defined (GDB_OSABI_DEFAULT) && (GDB_OSABI_DEFAULT == GDB_OSABI_OPENBSD_ELF) |
| 338 | #define GDB_OSABI_NETBSD_CORE GDB_OSABI_OPENBSD_ELF |
| 339 | #else |
| 340 | #define GDB_OSABI_NETBSD_CORE GDB_OSABI_NETBSD_AOUT |
| 341 | #endif |
| 342 | |
| 343 | static enum gdb_osabi |
| 344 | sparcnbsd_core_osabi_sniffer (bfd *abfd) |
| 345 | { |
| 346 | if (strcmp (bfd_get_target (abfd), "netbsd-core") == 0) |
| 347 | return GDB_OSABI_NETBSD_CORE; |
| 348 | |
| 349 | return GDB_OSABI_UNKNOWN; |
| 350 | } |
| 351 | |
| 352 | \f |
| 353 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
| 354 | void _initialize_sparcnbsd_tdep (void); |
| 355 | |
| 356 | void |
| 357 | _initialize_sparnbsd_tdep (void) |
| 358 | { |
| 359 | gdbarch_register_osabi_sniffer (bfd_arch_sparc, bfd_target_aout_flavour, |
| 360 | sparcnbsd_aout_osabi_sniffer); |
| 361 | |
| 362 | /* BFD doesn't set a flavour for NetBSD style a.out core files. */ |
| 363 | gdbarch_register_osabi_sniffer (bfd_arch_sparc, bfd_target_unknown_flavour, |
| 364 | sparcnbsd_core_osabi_sniffer); |
| 365 | |
| 366 | gdbarch_register_osabi (bfd_arch_sparc, 0, GDB_OSABI_NETBSD_AOUT, |
| 367 | sparc32nbsd_aout_init_abi); |
| 368 | gdbarch_register_osabi (bfd_arch_sparc, 0, GDB_OSABI_NETBSD_ELF, |
| 369 | sparc32nbsd_elf_init_abi); |
| 370 | } |