/* Target-dependent code for FreeBSD/amd64. Copyright (C) 2003-2017 Free Software Foundation, Inc. This file is part of GDB. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ #include "defs.h" #include "arch-utils.h" #include "frame.h" #include "gdbcore.h" #include "regcache.h" #include "osabi.h" #include "regset.h" #include "i386fbsd-tdep.h" #include "x86-xstate.h" #include "amd64-tdep.h" #include "bsd-uthread.h" #include "fbsd-tdep.h" #include "solib-svr4.h" /* Support for signal handlers. */ /* Return whether THIS_FRAME corresponds to a FreeBSD sigtramp routine. */ static const gdb_byte amd64fbsd_sigtramp_code[] = { 0x48, 0x8d, 0x7c, 0x24, 0x10, /* lea SIGF_UC(%rsp),%rdi */ 0x6a, 0x00, /* pushq $0 */ 0x48, 0xc7, 0xc0, 0xa1, 0x01, 0x00, 0x00, /* movq $SYS_sigreturn,%rax */ 0x0f, 0x05 /* syscall */ }; static int amd64fbsd_sigtramp_p (struct frame_info *this_frame) { CORE_ADDR pc = get_frame_pc (this_frame); gdb_byte buf[sizeof amd64fbsd_sigtramp_code]; if (!safe_frame_unwind_memory (this_frame, pc, buf, sizeof buf)) return 0; if (memcmp (buf, amd64fbsd_sigtramp_code, sizeof amd64fbsd_sigtramp_code) != 0) return 0; return 1; } /* Assuming THIS_FRAME is for a BSD sigtramp routine, return the address of the associated sigcontext structure. */ static CORE_ADDR amd64fbsd_sigcontext_addr (struct frame_info *this_frame) { struct gdbarch *gdbarch = get_frame_arch (this_frame); enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); CORE_ADDR sp; gdb_byte buf[8]; /* The `struct sigcontext' (which really is an `ucontext_t' on FreeBSD/amd64) lives at a fixed offset in the signal frame. See . */ get_frame_register (this_frame, AMD64_RSP_REGNUM, buf); sp = extract_unsigned_integer (buf, 8, byte_order); return sp + 16; } /* FreeBSD 5.1-RELEASE or later. */ /* Mapping between the general-purpose registers in `struct reg' format and GDB's register cache layout. Note that some registers are 32-bit, but since we're little-endian we get away with that. */ /* From . */ static int amd64fbsd_r_reg_offset[] = { 14 * 8, /* %rax */ 11 * 8, /* %rbx */ 13 * 8, /* %rcx */ 12 * 8, /* %rdx */ 9 * 8, /* %rsi */ 8 * 8, /* %rdi */ 10 * 8, /* %rbp */ 20 * 8, /* %rsp */ 7 * 8, /* %r8 ... */ 6 * 8, 5 * 8, 4 * 8, 3 * 8, 2 * 8, 1 * 8, 0 * 8, /* ... %r15 */ 17 * 8, /* %rip */ 19 * 8, /* %eflags */ 18 * 8, /* %cs */ 21 * 8, /* %ss */ -1, /* %ds */ -1, /* %es */ -1, /* %fs */ -1 /* %gs */ }; /* Location of the signal trampoline. */ CORE_ADDR amd64fbsd_sigtramp_start_addr; CORE_ADDR amd64fbsd_sigtramp_end_addr; /* From . */ int amd64fbsd_sc_reg_offset[] = { 24 + 6 * 8, /* %rax */ 24 + 7 * 8, /* %rbx */ 24 + 3 * 8, /* %rcx */ 24 + 2 * 8, /* %rdx */ 24 + 1 * 8, /* %rsi */ 24 + 0 * 8, /* %rdi */ 24 + 8 * 8, /* %rbp */ 24 + 22 * 8, /* %rsp */ 24 + 4 * 8, /* %r8 ... */ 24 + 5 * 8, 24 + 9 * 8, 24 + 10 * 8, 24 + 11 * 8, 24 + 12 * 8, 24 + 13 * 8, 24 + 14 * 8, /* ... %r15 */ 24 + 19 * 8, /* %rip */ 24 + 21 * 8, /* %eflags */ 24 + 20 * 8, /* %cs */ 24 + 23 * 8, /* %ss */ -1, /* %ds */ -1, /* %es */ -1, /* %fs */ -1 /* %gs */ }; /* From /usr/src/lib/libc/amd64/gen/_setjmp.S. */ static int amd64fbsd_jmp_buf_reg_offset[] = { -1, /* %rax */ 1 * 8, /* %rbx */ -1, /* %rcx */ -1, /* %rdx */ -1, /* %rsi */ -1, /* %rdi */ 3 * 8, /* %rbp */ 2 * 8, /* %rsp */ -1, /* %r8 ... */ -1, -1, -1, /* ... %r11 */ 4 * 8, /* %r12 ... */ 5 * 8, 6 * 8, 7 * 8, /* ... %r15 */ 0 * 8 /* %rip */ }; /* Implement the core_read_description gdbarch method. */ static const struct target_desc * amd64fbsd_core_read_description (struct gdbarch *gdbarch, struct target_ops *target, bfd *abfd) { return amd64_target_description (i386fbsd_core_read_xcr0 (abfd)); } /* Similar to amd64_supply_fpregset, but use XSAVE extended state. */ static void amd64fbsd_supply_xstateregset (const struct regset *regset, struct regcache *regcache, int regnum, const void *xstateregs, size_t len) { amd64_supply_xsave (regcache, regnum, xstateregs); } /* Similar to amd64_collect_fpregset, but use XSAVE extended state. */ static void amd64fbsd_collect_xstateregset (const struct regset *regset, const struct regcache *regcache, int regnum, void *xstateregs, size_t len) { amd64_collect_xsave (regcache, regnum, xstateregs, 1); } static const struct regset amd64fbsd_xstateregset = { NULL, amd64fbsd_supply_xstateregset, amd64fbsd_collect_xstateregset }; /* Iterate over core file register note sections. */ static void amd64fbsd_iterate_over_regset_sections (struct gdbarch *gdbarch, iterate_over_regset_sections_cb *cb, void *cb_data, const struct regcache *regcache) { struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); cb (".reg", tdep->sizeof_gregset, &i386_gregset, NULL, cb_data); cb (".reg2", tdep->sizeof_fpregset, &amd64_fpregset, NULL, cb_data); cb (".reg-xstate", X86_XSTATE_SIZE(tdep->xcr0), &amd64fbsd_xstateregset, "XSAVE extended state", cb_data); } static void amd64fbsd_supply_uthread (struct regcache *regcache, int regnum, CORE_ADDR addr) { gdb_byte buf[8]; int i; gdb_assert (regnum >= -1); for (i = 0; i < ARRAY_SIZE (amd64fbsd_jmp_buf_reg_offset); i++) { if (amd64fbsd_jmp_buf_reg_offset[i] != -1 && (regnum == -1 || regnum == i)) { read_memory (addr + amd64fbsd_jmp_buf_reg_offset[i], buf, 8); regcache_raw_supply (regcache, i, buf); } } } static void amd64fbsd_collect_uthread (const struct regcache *regcache, int regnum, CORE_ADDR addr) { gdb_byte buf[8]; int i; gdb_assert (regnum >= -1); for (i = 0; i < ARRAY_SIZE (amd64fbsd_jmp_buf_reg_offset); i++) { if (amd64fbsd_jmp_buf_reg_offset[i] != -1 && (regnum == -1 || regnum == i)) { regcache_raw_collect (regcache, i, buf); write_memory (addr + amd64fbsd_jmp_buf_reg_offset[i], buf, 8); } } } static void amd64fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) { struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); /* Generic FreeBSD support. */ fbsd_init_abi (info, gdbarch); /* Obviously FreeBSD is BSD-based. */ i386bsd_init_abi (info, gdbarch); tdep->gregset_reg_offset = amd64fbsd_r_reg_offset; tdep->gregset_num_regs = ARRAY_SIZE (amd64fbsd_r_reg_offset); tdep->sizeof_gregset = 22 * 8; amd64_init_abi (info, gdbarch); tdep->sigtramp_p = amd64fbsd_sigtramp_p; tdep->sigtramp_start = amd64fbsd_sigtramp_start_addr; tdep->sigtramp_end = amd64fbsd_sigtramp_end_addr; tdep->sigcontext_addr = amd64fbsd_sigcontext_addr; tdep->sc_reg_offset = amd64fbsd_sc_reg_offset; tdep->sc_num_regs = ARRAY_SIZE (amd64fbsd_sc_reg_offset); tdep->xsave_xcr0_offset = I386_FBSD_XSAVE_XCR0_OFFSET; /* Iterate over core file register note sections. */ set_gdbarch_iterate_over_regset_sections (gdbarch, amd64fbsd_iterate_over_regset_sections); set_gdbarch_core_read_description (gdbarch, amd64fbsd_core_read_description); /* FreeBSD provides a user-level threads implementation. */ bsd_uthread_set_supply_uthread (gdbarch, amd64fbsd_supply_uthread); bsd_uthread_set_collect_uthread (gdbarch, amd64fbsd_collect_uthread); /* FreeBSD uses SVR4-style shared libraries. */ set_solib_svr4_fetch_link_map_offsets (gdbarch, svr4_lp64_fetch_link_map_offsets); } /* Provide a prototype to silence -Wmissing-prototypes. */ void _initialize_amd64fbsd_tdep (void); void _initialize_amd64fbsd_tdep (void) { gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64, GDB_OSABI_FREEBSD_ELF, amd64fbsd_init_abi); }