1 /* Target-dependent code for PowerPC systems running FreeBSD. 2 3 Copyright (C) 2013-2023 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 "frame-unwind.h" 25 #include "gdbtypes.h" 26 #include "osabi.h" 27 #include "regcache.h" 28 #include "regset.h" 29 #include "symtab.h" 30 #include "target.h" 31 #include "trad-frame.h" 32 33 #include "ppc-tdep.h" 34 #include "ppc64-tdep.h" 35 #include "ppc-fbsd-tdep.h" 36 #include "fbsd-tdep.h" 37 #include "solib-svr4.h" 38 #include "inferior.h" 39 40 41 /* 32-bit regset descriptions. */ 42 43 static const struct ppc_reg_offsets ppc32_fbsd_reg_offsets = 44 { 45 /* General-purpose registers. */ 46 /* .r0_offset = */ 0, 47 /* .gpr_size = */ 4, 48 /* .xr_size = */ 4, 49 /* .pc_offset = */ 144, 50 /* .ps_offset = */ -1, 51 /* .cr_offset = */ 132, 52 /* .lr_offset = */ 128, 53 /* .ctr_offset = */ 140, 54 /* .xer_offset = */ 136, 55 /* .mq_offset = */ -1, 56 57 /* Floating-point registers. */ 58 /* .f0_offset = */ 0, 59 /* .fpscr_offset = */ 256, 60 /* .fpscr_size = */ 8 61 }; 62 63 /* 64-bit regset descriptions. */ 64 65 static const struct ppc_reg_offsets ppc64_fbsd_reg_offsets = 66 { 67 /* General-purpose registers. */ 68 /* .r0_offset = */ 0, 69 /* .gpr_size = */ 8, 70 /* .xr_size = */ 8, 71 /* .pc_offset = */ 288, 72 /* .ps_offset = */ -1, 73 /* .cr_offset = */ 264, 74 /* .lr_offset = */ 256, 75 /* .ctr_offset = */ 280, 76 /* .xer_offset = */ 272, 77 /* .mq_offset = */ -1, 78 79 /* Floating-point registers. */ 80 /* .f0_offset = */ 0, 81 /* .fpscr_offset = */ 256, 82 /* .fpscr_size = */ 8 83 }; 84 85 /* 32-bit general-purpose register set. */ 86 87 static const struct regset ppc32_fbsd_gregset = { 88 &ppc32_fbsd_reg_offsets, 89 ppc_supply_gregset, 90 ppc_collect_gregset 91 }; 92 93 /* 64-bit general-purpose register set. */ 94 95 static const struct regset ppc64_fbsd_gregset = { 96 &ppc64_fbsd_reg_offsets, 97 ppc_supply_gregset, 98 ppc_collect_gregset 99 }; 100 101 /* 32-/64-bit floating-point register set. */ 102 103 static const struct regset ppc32_fbsd_fpregset = { 104 &ppc32_fbsd_reg_offsets, 105 ppc_supply_fpregset, 106 ppc_collect_fpregset 107 }; 108 109 const struct regset * 110 ppc_fbsd_gregset (int wordsize) 111 { 112 return wordsize == 8 ? &ppc64_fbsd_gregset : &ppc32_fbsd_gregset; 113 } 114 115 const struct regset * 116 ppc_fbsd_fpregset (void) 117 { 118 return &ppc32_fbsd_fpregset; 119 } 120 121 /* Iterate over core file register note sections. */ 122 123 static void 124 ppcfbsd_iterate_over_regset_sections (struct gdbarch *gdbarch, 125 iterate_over_regset_sections_cb *cb, 126 void *cb_data, 127 const struct regcache *regcache) 128 { 129 ppc_gdbarch_tdep *tdep = gdbarch_tdep<ppc_gdbarch_tdep> (gdbarch); 130 131 if (tdep->wordsize == 4) 132 cb (".reg", 148, 148, &ppc32_fbsd_gregset, NULL, cb_data); 133 else 134 cb (".reg", 296, 296, &ppc64_fbsd_gregset, NULL, cb_data); 135 cb (".reg2", 264, 264, &ppc32_fbsd_fpregset, NULL, cb_data); 136 } 137 138 /* Default page size. */ 139 140 static const int ppcfbsd_page_size = 4096; 141 142 /* Offset for sigreturn(2). */ 143 144 static const int ppcfbsd_sigreturn_offset[] = { 145 0xc, /* FreeBSD 32-bit */ 146 -1 147 }; 148 149 /* Signal trampolines. */ 150 151 static int 152 ppcfbsd_sigtramp_frame_sniffer (const struct frame_unwind *self, 153 frame_info_ptr this_frame, 154 void **this_cache) 155 { 156 struct gdbarch *gdbarch = get_frame_arch (this_frame); 157 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); 158 CORE_ADDR pc = get_frame_pc (this_frame); 159 CORE_ADDR start_pc = (pc & ~(ppcfbsd_page_size - 1)); 160 const int *offset; 161 const char *name; 162 163 /* A stack trampoline is detected if no name is associated 164 to the current pc and if it points inside a trampoline 165 sequence. */ 166 167 find_pc_partial_function (pc, &name, NULL, NULL); 168 169 /* If we have a name, we have no trampoline, return. */ 170 if (name) 171 return 0; 172 173 for (offset = ppcfbsd_sigreturn_offset; *offset != -1; offset++) 174 { 175 gdb_byte buf[2 * PPC_INSN_SIZE]; 176 unsigned long insn; 177 178 if (!safe_frame_unwind_memory (this_frame, start_pc + *offset, 179 {buf, sizeof buf})) 180 continue; 181 182 /* Check for "li r0,SYS_sigreturn". */ 183 insn = extract_unsigned_integer (buf, PPC_INSN_SIZE, byte_order); 184 if (insn != 0x380001a1) 185 continue; 186 187 /* Check for "sc". */ 188 insn = extract_unsigned_integer (buf + PPC_INSN_SIZE, 189 PPC_INSN_SIZE, byte_order); 190 if (insn != 0x44000002) 191 continue; 192 193 return 1; 194 } 195 196 return 0; 197 } 198 199 static struct trad_frame_cache * 200 ppcfbsd_sigtramp_frame_cache (frame_info_ptr this_frame, void **this_cache) 201 { 202 struct gdbarch *gdbarch = get_frame_arch (this_frame); 203 ppc_gdbarch_tdep *tdep = gdbarch_tdep<ppc_gdbarch_tdep> (gdbarch); 204 struct trad_frame_cache *cache; 205 CORE_ADDR addr, base, func; 206 gdb_byte buf[PPC_INSN_SIZE]; 207 int i; 208 209 if (*this_cache) 210 return (struct trad_frame_cache *) *this_cache; 211 212 cache = trad_frame_cache_zalloc (this_frame); 213 *this_cache = cache; 214 215 func = get_frame_pc (this_frame); 216 func &= ~(ppcfbsd_page_size - 1); 217 if (!safe_frame_unwind_memory (this_frame, func, {buf, sizeof buf})) 218 return cache; 219 220 base = get_frame_register_unsigned (this_frame, gdbarch_sp_regnum (gdbarch)); 221 addr = base + 0x10 + 2 * tdep->wordsize; 222 for (i = 0; i < ppc_num_gprs; i++, addr += tdep->wordsize) 223 { 224 int regnum = i + tdep->ppc_gp0_regnum; 225 trad_frame_set_reg_addr (cache, regnum, addr); 226 } 227 trad_frame_set_reg_addr (cache, tdep->ppc_lr_regnum, addr); 228 addr += tdep->wordsize; 229 trad_frame_set_reg_addr (cache, tdep->ppc_cr_regnum, addr); 230 addr += tdep->wordsize; 231 trad_frame_set_reg_addr (cache, tdep->ppc_xer_regnum, addr); 232 addr += tdep->wordsize; 233 trad_frame_set_reg_addr (cache, tdep->ppc_ctr_regnum, addr); 234 addr += tdep->wordsize; 235 trad_frame_set_reg_addr (cache, gdbarch_pc_regnum (gdbarch), addr); 236 /* SRR0? */ 237 addr += tdep->wordsize; 238 239 /* Construct the frame ID using the function start. */ 240 trad_frame_set_id (cache, frame_id_build (base, func)); 241 242 return cache; 243 } 244 245 static void 246 ppcfbsd_sigtramp_frame_this_id (frame_info_ptr this_frame, 247 void **this_cache, struct frame_id *this_id) 248 { 249 struct trad_frame_cache *cache = 250 ppcfbsd_sigtramp_frame_cache (this_frame, this_cache); 251 252 trad_frame_get_id (cache, this_id); 253 } 254 255 static struct value * 256 ppcfbsd_sigtramp_frame_prev_register (frame_info_ptr this_frame, 257 void **this_cache, int regnum) 258 { 259 struct trad_frame_cache *cache = 260 ppcfbsd_sigtramp_frame_cache (this_frame, this_cache); 261 262 return trad_frame_get_register (cache, this_frame, regnum); 263 } 264 265 static const struct frame_unwind ppcfbsd_sigtramp_frame_unwind = { 266 "ppc freebsd sigtramp", 267 SIGTRAMP_FRAME, 268 default_frame_unwind_stop_reason, 269 ppcfbsd_sigtramp_frame_this_id, 270 ppcfbsd_sigtramp_frame_prev_register, 271 NULL, 272 ppcfbsd_sigtramp_frame_sniffer 273 }; 274 275 static enum return_value_convention 276 ppcfbsd_return_value (struct gdbarch *gdbarch, struct value *function, 277 struct type *valtype, struct regcache *regcache, 278 gdb_byte *readbuf, const gdb_byte *writebuf) 279 { 280 return ppc_sysv_abi_broken_return_value (gdbarch, function, valtype, 281 regcache, readbuf, writebuf); 282 } 283 284 /* Implement the "get_thread_local_address" gdbarch method. */ 285 286 static CORE_ADDR 287 ppcfbsd_get_thread_local_address (struct gdbarch *gdbarch, ptid_t ptid, 288 CORE_ADDR lm_addr, CORE_ADDR offset) 289 { 290 ppc_gdbarch_tdep *tdep = gdbarch_tdep<ppc_gdbarch_tdep> (gdbarch); 291 struct regcache *regcache; 292 int tp_offset, tp_regnum; 293 294 regcache = get_thread_arch_regcache (current_inferior ()->process_target (), 295 ptid, gdbarch); 296 297 if (tdep->wordsize == 4) 298 { 299 tp_offset = 0x7008; 300 tp_regnum = PPC_R0_REGNUM + 2; 301 } 302 else 303 { 304 tp_offset = 0x7010; 305 tp_regnum = PPC_R0_REGNUM + 13; 306 } 307 target_fetch_registers (regcache, tp_regnum); 308 309 ULONGEST tp; 310 if (regcache->cooked_read (tp_regnum, &tp) != REG_VALID) 311 error (_("Unable to fetch tcb pointer")); 312 313 /* tp points to the end of the TCB block. The first member of the 314 TCB is the pointer to the DTV array. */ 315 CORE_ADDR dtv_addr = tp - tp_offset; 316 return fbsd_get_thread_local_address (gdbarch, dtv_addr, lm_addr, offset); 317 } 318 319 static void 320 ppcfbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) 321 { 322 ppc_gdbarch_tdep *tdep = gdbarch_tdep<ppc_gdbarch_tdep> (gdbarch); 323 324 /* Generic FreeBSD support. */ 325 fbsd_init_abi (info, gdbarch); 326 327 /* FreeBSD doesn't support the 128-bit `long double' from the psABI. */ 328 set_gdbarch_long_double_bit (gdbarch, 64); 329 set_gdbarch_long_double_format (gdbarch, floatformats_ieee_double); 330 331 if (tdep->wordsize == 4) 332 { 333 set_gdbarch_return_value (gdbarch, ppcfbsd_return_value); 334 335 set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target); 336 set_solib_svr4_fetch_link_map_offsets (gdbarch, 337 svr4_ilp32_fetch_link_map_offsets); 338 339 frame_unwind_append_unwinder (gdbarch, &ppcfbsd_sigtramp_frame_unwind); 340 set_gdbarch_gcore_bfd_target (gdbarch, "elf32-powerpc"); 341 } 342 343 if (tdep->wordsize == 8) 344 { 345 set_gdbarch_convert_from_func_ptr_addr 346 (gdbarch, ppc64_convert_from_func_ptr_addr); 347 set_gdbarch_elf_make_msymbol_special (gdbarch, 348 ppc64_elf_make_msymbol_special); 349 350 set_gdbarch_skip_trampoline_code (gdbarch, ppc64_skip_trampoline_code); 351 set_solib_svr4_fetch_link_map_offsets (gdbarch, 352 svr4_lp64_fetch_link_map_offsets); 353 set_gdbarch_gcore_bfd_target (gdbarch, "elf64-powerpc"); 354 } 355 356 set_gdbarch_iterate_over_regset_sections 357 (gdbarch, ppcfbsd_iterate_over_regset_sections); 358 359 set_gdbarch_fetch_tls_load_module_address (gdbarch, 360 svr4_fetch_objfile_link_map); 361 set_gdbarch_get_thread_local_address (gdbarch, 362 ppcfbsd_get_thread_local_address); 363 } 364 365 void _initialize_ppcfbsd_tdep (); 366 void 367 _initialize_ppcfbsd_tdep () 368 { 369 gdbarch_register_osabi (bfd_arch_powerpc, bfd_mach_ppc, GDB_OSABI_FREEBSD, 370 ppcfbsd_init_abi); 371 gdbarch_register_osabi (bfd_arch_powerpc, bfd_mach_ppc64, GDB_OSABI_FREEBSD, 372 ppcfbsd_init_abi); 373 gdbarch_register_osabi (bfd_arch_rs6000, 0, GDB_OSABI_FREEBSD, 374 ppcfbsd_init_abi); 375 } 376