1 /* Target-dependent code for FreeBSD/amd64. 2 3 Copyright (C) 2003-2019 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 "osabi.h" 26 #include "regset.h" 27 #include "i386-fbsd-tdep.h" 28 #include "common/x86-xstate.h" 29 30 #include "amd64-tdep.h" 31 #include "fbsd-tdep.h" 32 #include "solib-svr4.h" 33 34 /* Support for signal handlers. */ 35 36 /* Return whether THIS_FRAME corresponds to a FreeBSD sigtramp 37 routine. */ 38 39 static const gdb_byte amd64fbsd_sigtramp_code[] = 40 { 41 0x48, 0x8d, 0x7c, 0x24, 0x10, /* lea SIGF_UC(%rsp),%rdi */ 42 0x6a, 0x00, /* pushq $0 */ 43 0x48, 0xc7, 0xc0, 0xa1, 0x01, 0x00, 0x00, 44 /* movq $SYS_sigreturn,%rax */ 45 0x0f, 0x05 /* syscall */ 46 }; 47 48 static int 49 amd64fbsd_sigtramp_p (struct frame_info *this_frame) 50 { 51 CORE_ADDR pc = get_frame_pc (this_frame); 52 gdb_byte buf[sizeof amd64fbsd_sigtramp_code]; 53 54 if (!safe_frame_unwind_memory (this_frame, pc, buf, sizeof buf)) 55 return 0; 56 if (memcmp (buf, amd64fbsd_sigtramp_code, sizeof amd64fbsd_sigtramp_code) 57 != 0) 58 return 0; 59 60 return 1; 61 } 62 63 /* Assuming THIS_FRAME is for a BSD sigtramp routine, return the 64 address of the associated sigcontext structure. */ 65 66 static CORE_ADDR 67 amd64fbsd_sigcontext_addr (struct frame_info *this_frame) 68 { 69 struct gdbarch *gdbarch = get_frame_arch (this_frame); 70 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); 71 CORE_ADDR sp; 72 gdb_byte buf[8]; 73 74 /* The `struct sigcontext' (which really is an `ucontext_t' on 75 FreeBSD/amd64) lives at a fixed offset in the signal frame. See 76 <machine/sigframe.h>. */ 77 get_frame_register (this_frame, AMD64_RSP_REGNUM, buf); 78 sp = extract_unsigned_integer (buf, 8, byte_order); 79 return sp + 16; 80 } 81 82 /* FreeBSD 5.1-RELEASE or later. */ 83 84 /* Mapping between the general-purpose registers in `struct reg' 85 format and GDB's register cache layout. 86 87 Note that some registers are 32-bit, but since we're little-endian 88 we get away with that. */ 89 90 /* From <machine/reg.h>. */ 91 static int amd64fbsd_r_reg_offset[] = 92 { 93 14 * 8, /* %rax */ 94 11 * 8, /* %rbx */ 95 13 * 8, /* %rcx */ 96 12 * 8, /* %rdx */ 97 9 * 8, /* %rsi */ 98 8 * 8, /* %rdi */ 99 10 * 8, /* %rbp */ 100 20 * 8, /* %rsp */ 101 7 * 8, /* %r8 ... */ 102 6 * 8, 103 5 * 8, 104 4 * 8, 105 3 * 8, 106 2 * 8, 107 1 * 8, 108 0 * 8, /* ... %r15 */ 109 17 * 8, /* %rip */ 110 19 * 8, /* %eflags */ 111 18 * 8, /* %cs */ 112 21 * 8, /* %ss */ 113 -1, /* %ds */ 114 -1, /* %es */ 115 -1, /* %fs */ 116 -1 /* %gs */ 117 }; 118 119 /* Location of the signal trampoline. */ 120 CORE_ADDR amd64fbsd_sigtramp_start_addr; 121 CORE_ADDR amd64fbsd_sigtramp_end_addr; 122 123 /* From <machine/signal.h>. */ 124 int amd64fbsd_sc_reg_offset[] = 125 { 126 24 + 6 * 8, /* %rax */ 127 24 + 7 * 8, /* %rbx */ 128 24 + 3 * 8, /* %rcx */ 129 24 + 2 * 8, /* %rdx */ 130 24 + 1 * 8, /* %rsi */ 131 24 + 0 * 8, /* %rdi */ 132 24 + 8 * 8, /* %rbp */ 133 24 + 22 * 8, /* %rsp */ 134 24 + 4 * 8, /* %r8 ... */ 135 24 + 5 * 8, 136 24 + 9 * 8, 137 24 + 10 * 8, 138 24 + 11 * 8, 139 24 + 12 * 8, 140 24 + 13 * 8, 141 24 + 14 * 8, /* ... %r15 */ 142 24 + 19 * 8, /* %rip */ 143 24 + 21 * 8, /* %eflags */ 144 24 + 20 * 8, /* %cs */ 145 24 + 23 * 8, /* %ss */ 146 -1, /* %ds */ 147 -1, /* %es */ 148 -1, /* %fs */ 149 -1 /* %gs */ 150 }; 151 152 /* Implement the core_read_description gdbarch method. */ 153 154 static const struct target_desc * 155 amd64fbsd_core_read_description (struct gdbarch *gdbarch, 156 struct target_ops *target, 157 bfd *abfd) 158 { 159 return amd64_target_description (i386fbsd_core_read_xcr0 (abfd), true); 160 } 161 162 /* Similar to amd64_supply_fpregset, but use XSAVE extended state. */ 163 164 static void 165 amd64fbsd_supply_xstateregset (const struct regset *regset, 166 struct regcache *regcache, int regnum, 167 const void *xstateregs, size_t len) 168 { 169 amd64_supply_xsave (regcache, regnum, xstateregs); 170 } 171 172 /* Similar to amd64_collect_fpregset, but use XSAVE extended state. */ 173 174 static void 175 amd64fbsd_collect_xstateregset (const struct regset *regset, 176 const struct regcache *regcache, 177 int regnum, void *xstateregs, size_t len) 178 { 179 amd64_collect_xsave (regcache, regnum, xstateregs, 1); 180 } 181 182 static const struct regset amd64fbsd_xstateregset = 183 { 184 NULL, 185 amd64fbsd_supply_xstateregset, 186 amd64fbsd_collect_xstateregset 187 }; 188 189 /* Iterate over core file register note sections. */ 190 191 static void 192 amd64fbsd_iterate_over_regset_sections (struct gdbarch *gdbarch, 193 iterate_over_regset_sections_cb *cb, 194 void *cb_data, 195 const struct regcache *regcache) 196 { 197 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); 198 199 cb (".reg", tdep->sizeof_gregset, tdep->sizeof_gregset, &i386_gregset, NULL, 200 cb_data); 201 cb (".reg2", tdep->sizeof_fpregset, tdep->sizeof_fpregset, &amd64_fpregset, 202 NULL, cb_data); 203 cb (".reg-xstate", X86_XSTATE_SIZE (tdep->xcr0), X86_XSTATE_SIZE (tdep->xcr0), 204 &amd64fbsd_xstateregset, "XSAVE extended state", cb_data); 205 } 206 207 static void 208 amd64fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) 209 { 210 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); 211 212 /* Generic FreeBSD support. */ 213 fbsd_init_abi (info, gdbarch); 214 215 /* Obviously FreeBSD is BSD-based. */ 216 i386bsd_init_abi (info, gdbarch); 217 218 tdep->gregset_reg_offset = amd64fbsd_r_reg_offset; 219 tdep->gregset_num_regs = ARRAY_SIZE (amd64fbsd_r_reg_offset); 220 tdep->sizeof_gregset = 22 * 8; 221 222 amd64_init_abi (info, gdbarch, 223 amd64_target_description (X86_XSTATE_SSE_MASK, true)); 224 225 tdep->sigtramp_p = amd64fbsd_sigtramp_p; 226 tdep->sigtramp_start = amd64fbsd_sigtramp_start_addr; 227 tdep->sigtramp_end = amd64fbsd_sigtramp_end_addr; 228 tdep->sigcontext_addr = amd64fbsd_sigcontext_addr; 229 tdep->sc_reg_offset = amd64fbsd_sc_reg_offset; 230 tdep->sc_num_regs = ARRAY_SIZE (amd64fbsd_sc_reg_offset); 231 232 tdep->xsave_xcr0_offset = I386_FBSD_XSAVE_XCR0_OFFSET; 233 234 /* Iterate over core file register note sections. */ 235 set_gdbarch_iterate_over_regset_sections 236 (gdbarch, amd64fbsd_iterate_over_regset_sections); 237 238 set_gdbarch_core_read_description (gdbarch, 239 amd64fbsd_core_read_description); 240 241 /* FreeBSD uses SVR4-style shared libraries. */ 242 set_solib_svr4_fetch_link_map_offsets 243 (gdbarch, svr4_lp64_fetch_link_map_offsets); 244 } 245 246 void 247 _initialize_amd64fbsd_tdep (void) 248 { 249 gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64, 250 GDB_OSABI_FREEBSD, amd64fbsd_init_abi); 251 } 252