1/* Target-dependent code for OpenBSD/amd64. 2 3 Copyright 2003, 2004 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 2 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, write to the Free Software 19 Foundation, Inc., 59 Temple Place - Suite 330, 20 Boston, MA 02111-1307, USA. */ 21 22#include "defs.h" 23#include "frame.h" 24#include "gdbcore.h" 25#include "osabi.h" 26#include "regset.h" 27#include "target.h" 28 29#include "gdb_assert.h" 30#include "gdb_string.h" 31 32#include "amd64-tdep.h" 33#include "i387-tdep.h" 34#include "solib-svr4.h" 35 36/* Support for core dumps. */ 37 38static void 39amd64obsd_supply_regset (const struct regset *regset, 40 struct regcache *regcache, int regnum, 41 const void *regs, size_t len) 42{ 43 const struct gdbarch_tdep *tdep = regset->descr; 44 45 gdb_assert (len >= tdep->sizeof_gregset + I387_SIZEOF_FXSAVE); 46 47 i386_supply_gregset (regset, regcache, regnum, regs, tdep->sizeof_gregset); 48 amd64_supply_fxsave (regcache, regnum, (char *)regs + tdep->sizeof_gregset); 49} 50 51static const struct regset * 52amd64obsd_regset_from_core_section (struct gdbarch *gdbarch, 53 const char *sect_name, size_t sect_size) 54{ 55 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); 56 57 /* OpenBSD core dumps don't use seperate register sets for the 58 general-purpose and floating-point registers. */ 59 60 if (strcmp (sect_name, ".reg") == 0 61 && sect_size >= tdep->sizeof_gregset + I387_SIZEOF_FXSAVE) 62 { 63 if (tdep->gregset == NULL) 64 { 65 tdep->gregset = XMALLOC (struct regset); 66 tdep->gregset->descr = tdep; 67 tdep->gregset->supply_regset = amd64obsd_supply_regset; 68 } 69 return tdep->gregset; 70 } 71 72 return NULL; 73} 74 75 76/* Support for signal handlers. */ 77 78static const int amd64obsd_page_size = 4096; 79 80static int 81amd64obsd_pc_in_sigtramp (CORE_ADDR pc, char *name) 82{ 83 CORE_ADDR start_pc = (pc & ~(amd64obsd_page_size - 1)); 84 const char sigreturn[] = 85 { 86 0x48, 0xc7, 0xc0, 87 0x67, 0x00, 0x00, 0x00, /* movq $SYS_sigreturn, %rax */ 88 0xcd, 0x80 /* int $0x80 */ 89 }; 90 char *buf; 91 92 if (name) 93 return 0; 94 95 /* If we can't read the instructions at START_PC, return zero. */ 96 buf = alloca (sizeof sigreturn); 97 if (target_read_memory (start_pc + 0x7, buf, sizeof sigreturn)) 98 return 0; 99 100 /* Check for sigreturn(2). */ 101 if (memcmp (buf, sigreturn, sizeof sigreturn)) 102 return 0; 103 104 return 1; 105} 106 107/* Assuming NEXT_FRAME is for a frame following a BSD sigtramp 108 routine, return the address of the associated sigcontext structure. */ 109 110static CORE_ADDR 111amd64obsd_sigcontext_addr (struct frame_info *next_frame) 112{ 113 /* The %rsp register points at `struct sigcontext' upon entry of a 114 signal trampoline. */ 115 return frame_unwind_register_unsigned (next_frame, AMD64_RSP_REGNUM); 116} 117 118/* OpenBSD 3.5 or later. */ 119 120/* Mapping between the general-purpose registers in `struct reg' 121 format and GDB's register cache layout. */ 122 123/* From <machine/reg.h>. */ 124int amd64obsd_r_reg_offset[] = 125{ 126 14 * 8, /* %rax */ 127 13 * 8, /* %rbx */ 128 3 * 8, /* %rcx */ 129 2 * 8, /* %rdx */ 130 1 * 8, /* %rsi */ 131 0 * 8, /* %rdi */ 132 12 * 8, /* %rbp */ 133 15 * 8, /* %rsp */ 134 4 * 8, /* %r8 .. */ 135 5 * 8, 136 6 * 8, 137 7 * 8, 138 8 * 8, 139 9 * 8, 140 10 * 8, 141 11 * 8, /* ... %r15 */ 142 16 * 8, /* %rip */ 143 17 * 8, /* %eflags */ 144 18 * 8, /* %cs */ 145 19 * 8, /* %ss */ 146 20 * 8, /* %ds */ 147 21 * 8, /* %es */ 148 22 * 8, /* %fs */ 149 23 * 8 /* %gs */ 150}; 151 152/* From <machine/signal.h>. */ 153static int amd64obsd_sc_reg_offset[] = 154{ 155 14 * 8, /* %rax */ 156 13 * 8, /* %rbx */ 157 3 * 8, /* %rcx */ 158 2 * 8, /* %rdx */ 159 1 * 8, /* %rsi */ 160 0 * 8, /* %rdi */ 161 12 * 8, /* %rbp */ 162 24 * 8, /* %rsp */ 163 4 * 8, /* %r8 ... */ 164 5 * 8, 165 6 * 8, 166 7 * 8, 167 8 * 8, 168 9 * 8, 169 10 * 8, 170 11 * 8, /* ... %r15 */ 171 21 * 8, /* %rip */ 172 23 * 8, /* %eflags */ 173 22 * 8, /* %cs */ 174 25 * 8, /* %ss */ 175 18 * 8, /* %ds */ 176 17 * 8, /* %es */ 177 16 * 8, /* %fs */ 178 15 * 8 /* %gs */ 179}; 180 181static void 182amd64obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) 183{ 184 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); 185 186 amd64_init_abi (info, gdbarch); 187 188 /* Initialize general-purpose register set details. */ 189 tdep->gregset_reg_offset = amd64obsd_r_reg_offset; 190 tdep->gregset_num_regs = ARRAY_SIZE (amd64obsd_r_reg_offset); 191 tdep->sizeof_gregset = 24 * 8; 192 193 set_gdbarch_regset_from_core_section (gdbarch, 194 amd64obsd_regset_from_core_section); 195 196 tdep->jb_pc_offset = 7 * 8; 197 198 set_gdbarch_pc_in_sigtramp (gdbarch, amd64obsd_pc_in_sigtramp); 199 tdep->sigcontext_addr = amd64obsd_sigcontext_addr; 200 tdep->sc_reg_offset = amd64obsd_sc_reg_offset; 201 tdep->sc_num_regs = ARRAY_SIZE (amd64obsd_sc_reg_offset); 202 203 /* OpenBSD uses SVR4-style shared libraries. */ 204 set_solib_svr4_fetch_link_map_offsets 205 (gdbarch, svr4_lp64_fetch_link_map_offsets); 206} 207 208 209/* Provide a prototype to silence -Wmissing-prototypes. */ 210void _initialize_amd64obsd_tdep (void); 211 212void 213_initialize_amd64obsd_tdep (void) 214{ 215 /* The OpenBSD/amd64 native dependent code makes this assumption. */ 216 gdb_assert (ARRAY_SIZE (amd64obsd_r_reg_offset) == AMD64_NUM_GREGS); 217 218 gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64, 219 GDB_OSABI_OPENBSD_ELF, amd64obsd_init_abi); 220 221 /* OpenBSD uses traditional (a.out) NetBSD-style core dumps. */ 222 gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64, 223 GDB_OSABI_NETBSD_AOUT, amd64obsd_init_abi); 224} 225