| 1 | /* Target-dependent code for NetBSD/i386. |
| 2 | |
| 3 | Copyright (C) 1988-2017 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "arch-utils.h" |
| 22 | #include "frame.h" |
| 23 | #include "gdbcore.h" |
| 24 | #include "regcache.h" |
| 25 | #include "regset.h" |
| 26 | #include "osabi.h" |
| 27 | #include "symtab.h" |
| 28 | #include "trad-frame.h" |
| 29 | #include "tramp-frame.h" |
| 30 | |
| 31 | #include "i386-tdep.h" |
| 32 | #include "i387-tdep.h" |
| 33 | #include "nbsd-tdep.h" |
| 34 | #include "solib-svr4.h" |
| 35 | |
| 36 | /* From <machine/reg.h>. */ |
| 37 | static int i386nbsd_r_reg_offset[] = |
| 38 | { |
| 39 | 0 * 4, /* %eax */ |
| 40 | 1 * 4, /* %ecx */ |
| 41 | 2 * 4, /* %edx */ |
| 42 | 3 * 4, /* %ebx */ |
| 43 | 4 * 4, /* %esp */ |
| 44 | 5 * 4, /* %ebp */ |
| 45 | 6 * 4, /* %esi */ |
| 46 | 7 * 4, /* %edi */ |
| 47 | 8 * 4, /* %eip */ |
| 48 | 9 * 4, /* %eflags */ |
| 49 | 10 * 4, /* %cs */ |
| 50 | 11 * 4, /* %ss */ |
| 51 | 12 * 4, /* %ds */ |
| 52 | 13 * 4, /* %es */ |
| 53 | 14 * 4, /* %fs */ |
| 54 | 15 * 4 /* %gs */ |
| 55 | }; |
| 56 | |
| 57 | /* From <machine/signal.h>. */ |
| 58 | int i386nbsd_sc_reg_offset[] = |
| 59 | { |
| 60 | 10 * 4, /* %eax */ |
| 61 | 9 * 4, /* %ecx */ |
| 62 | 8 * 4, /* %edx */ |
| 63 | 7 * 4, /* %ebx */ |
| 64 | 14 * 4, /* %esp */ |
| 65 | 6 * 4, /* %ebp */ |
| 66 | 5 * 4, /* %esi */ |
| 67 | 4 * 4, /* %edi */ |
| 68 | 11 * 4, /* %eip */ |
| 69 | 13 * 4, /* %eflags */ |
| 70 | 12 * 4, /* %cs */ |
| 71 | 15 * 4, /* %ss */ |
| 72 | 3 * 4, /* %ds */ |
| 73 | 2 * 4, /* %es */ |
| 74 | 1 * 4, /* %fs */ |
| 75 | 0 * 4 /* %gs */ |
| 76 | }; |
| 77 | |
| 78 | /* From <machine/mcontext.h>. */ |
| 79 | int i386nbsd_mc_reg_offset[] = |
| 80 | { |
| 81 | 11 * 4, /* %eax */ |
| 82 | 10 * 4, /* %ecx */ |
| 83 | 9 * 4, /* %edx */ |
| 84 | 8 * 4, /* %ebx */ |
| 85 | 7 * 4, /* %esp */ |
| 86 | 6 * 4, /* %ebp */ |
| 87 | 5 * 4, /* %esi */ |
| 88 | 4 * 4, /* %edi */ |
| 89 | 14 * 4, /* %eip */ |
| 90 | 16 * 4, /* %eflags */ |
| 91 | 15 * 4, /* %cs */ |
| 92 | 18 * 4, /* %ss */ |
| 93 | 3 * 4, /* %ds */ |
| 94 | 2 * 4, /* %es */ |
| 95 | 1 * 4, /* %fs */ |
| 96 | 0 * 4 /* %gs */ |
| 97 | }; |
| 98 | |
| 99 | static void i386nbsd_sigtramp_cache_init (const struct tramp_frame *, |
| 100 | struct frame_info *, |
| 101 | struct trad_frame_cache *, |
| 102 | CORE_ADDR); |
| 103 | |
| 104 | static const struct tramp_frame i386nbsd_sigtramp_sc16 = |
| 105 | { |
| 106 | SIGTRAMP_FRAME, |
| 107 | 1, |
| 108 | { |
| 109 | { 0x8d, -1 }, { 0x44, -1 }, { 0x24, -1 }, { 0x10, -1 }, |
| 110 | /* leal 0x10(%esp), %eax */ |
| 111 | { 0x50, -1 }, /* pushl %eax */ |
| 112 | { 0x50, -1 }, /* pushl %eax */ |
| 113 | { 0xb8, -1 }, { 0x27, -1 }, {0x01, -1 }, {0x00, -1 }, {0x00, -1 }, |
| 114 | /* movl $0x127, %eax # __sigreturn14 */ |
| 115 | { 0xcd, -1 }, { 0x80, -1}, |
| 116 | /* int $0x80 */ |
| 117 | { 0xb8, -1 }, { 0x01, -1 }, {0x00, -1 }, {0x00, -1 }, {0x00, -1 }, |
| 118 | /* movl $0x1, %eax # exit */ |
| 119 | { 0xcd, -1 }, { 0x80, -1}, |
| 120 | /* int $0x80 */ |
| 121 | { TRAMP_SENTINEL_INSN, -1 } |
| 122 | }, |
| 123 | i386nbsd_sigtramp_cache_init |
| 124 | }; |
| 125 | |
| 126 | static const struct tramp_frame i386nbsd_sigtramp_sc2 = |
| 127 | { |
| 128 | SIGTRAMP_FRAME, |
| 129 | 1, |
| 130 | { |
| 131 | { 0x8d, -1 }, { 0x44, -1 }, { 0x24, -1 }, { 0x0c, -1 }, |
| 132 | /* leal 0x0c(%esp), %eax */ |
| 133 | { 0x89, -1 }, { 0x44, -1 }, { 0x24, -1 }, { 0x04, -1 }, |
| 134 | /* movl %eax, 0x4(%esp) */ |
| 135 | { 0xb8, -1 }, { 0x27, -1 }, {0x01, -1 }, {0x00, -1 }, {0x00, -1 }, |
| 136 | /* movl $0x127, %eax # __sigreturn14 */ |
| 137 | { 0xcd, -1 }, { 0x80, -1}, |
| 138 | /* int $0x80 */ |
| 139 | { 0x89, -1 }, { 0x44, -1 }, { 0x24, -1 }, { 0x04, -1 }, |
| 140 | /* movl %eax, 0x4(%esp) */ |
| 141 | { 0xb8, -1 }, { 0x01, -1 }, {0x00, -1 }, {0x00, -1 }, {0x00, -1 }, |
| 142 | /* movl $0x1, %eax */ |
| 143 | { 0xcd, -1 }, { 0x80, -1}, |
| 144 | /* int $0x80 */ |
| 145 | { TRAMP_SENTINEL_INSN, -1 } |
| 146 | }, |
| 147 | i386nbsd_sigtramp_cache_init |
| 148 | }; |
| 149 | |
| 150 | static const struct tramp_frame i386nbsd_sigtramp_si2 = |
| 151 | { |
| 152 | SIGTRAMP_FRAME, |
| 153 | 1, |
| 154 | { |
| 155 | { 0x8b, -1 }, { 0x44, -1 }, { 0x24, -1 }, { 0x08, -1 }, |
| 156 | /* movl 8(%esp),%eax */ |
| 157 | { 0x89, -1 }, { 0x44, -1 }, { 0x24, -1 }, { 0x04, -1 }, |
| 158 | /* movl %eax, 0x4(%esp) */ |
| 159 | { 0xb8, -1 }, { 0x34, -1 }, { 0x01, -1 }, { 0x00, -1 }, { 0x00, -1 }, |
| 160 | /* movl $0x134, %eax # setcontext */ |
| 161 | { 0xcd, -1 }, { 0x80, -1 }, |
| 162 | /* int $0x80 */ |
| 163 | { 0x89, -1 }, { 0x44, -1 }, { 0x24, -1 }, { 0x04, -1 }, |
| 164 | /* movl %eax, 0x4(%esp) */ |
| 165 | { 0xb8, -1 }, { 0x01, -1 }, { 0x00, -1 }, { 0x00, -1 }, { 0x00, -1 }, |
| 166 | /* movl $0x1, %eax */ |
| 167 | { 0xcd, -1 }, { 0x80, -1 }, |
| 168 | /* int $0x80 */ |
| 169 | { TRAMP_SENTINEL_INSN, -1 } |
| 170 | }, |
| 171 | i386nbsd_sigtramp_cache_init |
| 172 | }; |
| 173 | |
| 174 | static const struct tramp_frame i386nbsd_sigtramp_si31 = |
| 175 | { |
| 176 | SIGTRAMP_FRAME, |
| 177 | 1, |
| 178 | { |
| 179 | { 0x8d, -1 }, { 0x84, -1 }, { 0x24, -1 }, |
| 180 | { 0x8c, -1 }, { 0x00, -1 }, { 0x00, -1 }, { 0x00, -1 }, |
| 181 | /* leal 0x8c(%esp), %eax */ |
| 182 | { 0x89, -1 }, { 0x44, -1 }, { 0x24, -1 }, { 0x04, -1 }, |
| 183 | /* movl %eax, 0x4(%esp) */ |
| 184 | { 0xb8, -1 }, { 0x34, -1 }, { 0x01, -1 }, { 0x00, -1 }, { 0x00, -1 }, |
| 185 | /* movl $0x134, %eax # setcontext */ |
| 186 | { 0xcd, -1 }, { 0x80, -1}, |
| 187 | /* int $0x80 */ |
| 188 | { 0x89, -1 }, { 0x44, -1 }, { 0x24, -1 }, { 0x04, -1 }, |
| 189 | /* movl %eax, 0x4(%esp) */ |
| 190 | { 0xb8, -1 }, { 0x01, -1 }, {0x00, -1 }, {0x00, -1 }, {0x00, -1 }, |
| 191 | /* movl $0x1, %eax */ |
| 192 | { 0xcd, -1 }, { 0x80, -1}, |
| 193 | /* int $0x80 */ |
| 194 | { TRAMP_SENTINEL_INSN, -1 } |
| 195 | }, |
| 196 | i386nbsd_sigtramp_cache_init |
| 197 | }; |
| 198 | |
| 199 | static const struct tramp_frame i386nbsd_sigtramp_si4 = |
| 200 | { |
| 201 | SIGTRAMP_FRAME, |
| 202 | 1, |
| 203 | { |
| 204 | { 0x8d, -1 }, { 0x84, -1 }, { 0x24, -1 }, |
| 205 | { 0x8c, -1 }, { 0x00, -1 }, { 0x00, -1 }, { 0x00, -1 }, |
| 206 | /* leal 0x8c(%esp), %eax */ |
| 207 | { 0x89, -1 }, { 0x44, -1 }, { 0x24, -1 }, { 0x04, -1 }, |
| 208 | /* movl %eax, 0x4(%esp) */ |
| 209 | { 0xb8, -1 }, { 0x34, -1 }, { 0x01, -1 }, { 0x00, -1 }, { 0x00, -1 }, |
| 210 | /* movl $0x134, %eax # setcontext */ |
| 211 | { 0xcd, -1 }, { 0x80, -1}, |
| 212 | /* int $0x80 */ |
| 213 | { 0xc7, -1 }, { 0x44, -1 }, { 0x24, -1 }, { 0x04, -1 }, |
| 214 | { 0xff, -1 }, { 0xff, -1 }, { 0xff, -1 }, { 0xff, -1 }, |
| 215 | /* movl $0xffffffff,0x4(%esp) */ |
| 216 | { 0xb8, -1 }, { 0x01, -1 }, {0x00, -1 }, {0x00, -1 }, {0x00, -1 }, |
| 217 | /* movl $0x1, %eax */ |
| 218 | { 0xcd, -1 }, { 0x80, -1}, |
| 219 | /* int $0x80 */ |
| 220 | { TRAMP_SENTINEL_INSN, -1 } |
| 221 | }, |
| 222 | i386nbsd_sigtramp_cache_init |
| 223 | }; |
| 224 | |
| 225 | static void |
| 226 | i386nbsd_sigtramp_cache_init (const struct tramp_frame *self, |
| 227 | struct frame_info *this_frame, |
| 228 | struct trad_frame_cache *this_cache, |
| 229 | CORE_ADDR func) |
| 230 | { |
| 231 | struct gdbarch *gdbarch = get_frame_arch (this_frame); |
| 232 | enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); |
| 233 | CORE_ADDR sp = get_frame_register_unsigned (this_frame, I386_ESP_REGNUM); |
| 234 | CORE_ADDR base; |
| 235 | int *reg_offset; |
| 236 | int num_regs; |
| 237 | int i; |
| 238 | |
| 239 | if (self == &i386nbsd_sigtramp_sc16 || self == &i386nbsd_sigtramp_sc2) |
| 240 | { |
| 241 | reg_offset = i386nbsd_sc_reg_offset; |
| 242 | num_regs = ARRAY_SIZE (i386nbsd_sc_reg_offset); |
| 243 | |
| 244 | /* Read in the sigcontext address. */ |
| 245 | base = read_memory_unsigned_integer (sp + 8, 4, byte_order); |
| 246 | } |
| 247 | else |
| 248 | { |
| 249 | reg_offset = i386nbsd_mc_reg_offset; |
| 250 | num_regs = ARRAY_SIZE (i386nbsd_mc_reg_offset); |
| 251 | |
| 252 | /* Read in the ucontext address. */ |
| 253 | base = read_memory_unsigned_integer (sp + 8, 4, byte_order); |
| 254 | /* offsetof(ucontext_t, uc_mcontext) == 36 */ |
| 255 | base += 36; |
| 256 | } |
| 257 | |
| 258 | for (i = 0; i < num_regs; i++) |
| 259 | if (reg_offset[i] != -1) |
| 260 | trad_frame_set_reg_addr (this_cache, i, base + reg_offset[i]); |
| 261 | |
| 262 | /* Construct the frame ID using the function start. */ |
| 263 | trad_frame_set_id (this_cache, frame_id_build (sp, func)); |
| 264 | } |
| 265 | \f |
| 266 | |
| 267 | static void |
| 268 | i386nbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 269 | { |
| 270 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 271 | |
| 272 | /* Obviously NetBSD is BSD-based. */ |
| 273 | i386bsd_init_abi (info, gdbarch); |
| 274 | |
| 275 | /* NetBSD has a different `struct reg'. */ |
| 276 | tdep->gregset_reg_offset = i386nbsd_r_reg_offset; |
| 277 | tdep->gregset_num_regs = ARRAY_SIZE (i386nbsd_r_reg_offset); |
| 278 | tdep->sizeof_gregset = 16 * 4; |
| 279 | |
| 280 | /* NetBSD uses -freg-struct-return by default. */ |
| 281 | tdep->struct_return = reg_struct_return; |
| 282 | |
| 283 | /* NetBSD uses tramp_frame sniffers for signal trampolines. */ |
| 284 | tdep->sigcontext_addr= 0; |
| 285 | tdep->sigtramp_start = 0; |
| 286 | tdep->sigtramp_end = 0; |
| 287 | tdep->sigtramp_p = 0; |
| 288 | tdep->sc_reg_offset = 0; |
| 289 | tdep->sc_num_regs = 0; |
| 290 | |
| 291 | tramp_frame_prepend_unwinder (gdbarch, &i386nbsd_sigtramp_sc16); |
| 292 | tramp_frame_prepend_unwinder (gdbarch, &i386nbsd_sigtramp_sc2); |
| 293 | tramp_frame_prepend_unwinder (gdbarch, &i386nbsd_sigtramp_si2); |
| 294 | tramp_frame_prepend_unwinder (gdbarch, &i386nbsd_sigtramp_si31); |
| 295 | tramp_frame_prepend_unwinder (gdbarch, &i386nbsd_sigtramp_si4); |
| 296 | } |
| 297 | |
| 298 | /* NetBSD ELF. */ |
| 299 | |
| 300 | static void |
| 301 | i386nbsdelf_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 302 | { |
| 303 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 304 | |
| 305 | /* It's still NetBSD. */ |
| 306 | i386nbsd_init_abi (info, gdbarch); |
| 307 | |
| 308 | /* But ELF-based. */ |
| 309 | i386_elf_init_abi (info, gdbarch); |
| 310 | |
| 311 | /* NetBSD ELF uses SVR4-style shared libraries. */ |
| 312 | set_solib_svr4_fetch_link_map_offsets |
| 313 | (gdbarch, svr4_ilp32_fetch_link_map_offsets); |
| 314 | |
| 315 | /* NetBSD ELF uses -fpcc-struct-return by default. */ |
| 316 | tdep->struct_return = pcc_struct_return; |
| 317 | } |
| 318 | |
| 319 | void |
| 320 | _initialize_i386nbsd_tdep (void) |
| 321 | { |
| 322 | gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_NETBSD, |
| 323 | i386nbsdelf_init_abi); |
| 324 | } |