/* Target-dependent code for FreeBSD/amd64.
Copyright (C) 2003-2024 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 "osabi.h"
#include "regset.h"
#include "target.h"
#include "trad-frame.h"
#include "tramp-frame.h"
#include "i386-fbsd-tdep.h"
#include "gdbsupport/x86-xstate.h"
#include "amd64-tdep.h"
#include "amd64-fbsd-tdep.h"
#include "fbsd-tdep.h"
#include "solib-svr4.h"
#include "inferior.h"
/* The general-purpose regset consists of 22 64-bit slots, most of
which contain individual registers, but a few contain multiple
16-bit segment registers. */
#define AMD64_FBSD_SIZEOF_GREGSET (22 * 8)
/* The segment base register set consists of 2 64-bit registers. */
#define AMD64_FBSD_SIZEOF_SEGBASES_REGSET (2 * 8)
/* Register maps. */
static const struct regcache_map_entry amd64_fbsd_gregmap[] =
{
{ 1, AMD64_R15_REGNUM, 0 },
{ 1, AMD64_R14_REGNUM, 0 },
{ 1, AMD64_R13_REGNUM, 0 },
{ 1, AMD64_R12_REGNUM, 0 },
{ 1, AMD64_R11_REGNUM, 0 },
{ 1, AMD64_R10_REGNUM, 0 },
{ 1, AMD64_R9_REGNUM, 0 },
{ 1, AMD64_R8_REGNUM, 0 },
{ 1, AMD64_RDI_REGNUM, 0 },
{ 1, AMD64_RSI_REGNUM, 0 },
{ 1, AMD64_RBP_REGNUM, 0 },
{ 1, AMD64_RBX_REGNUM, 0 },
{ 1, AMD64_RDX_REGNUM, 0 },
{ 1, AMD64_RCX_REGNUM, 0 },
{ 1, AMD64_RAX_REGNUM, 0 },
{ 1, REGCACHE_MAP_SKIP, 4 }, /* trapno */
{ 1, AMD64_FS_REGNUM, 2 },
{ 1, AMD64_GS_REGNUM, 2 },
{ 1, REGCACHE_MAP_SKIP, 4 }, /* err */
{ 1, AMD64_ES_REGNUM, 2 },
{ 1, AMD64_DS_REGNUM, 2 },
{ 1, AMD64_RIP_REGNUM, 0 },
{ 1, AMD64_CS_REGNUM, 8 },
{ 1, AMD64_EFLAGS_REGNUM, 8 },
{ 1, AMD64_RSP_REGNUM, 0 },
{ 1, AMD64_SS_REGNUM, 8 },
{ 0 }
};
static const struct regcache_map_entry amd64_fbsd_segbases_regmap[] =
{
{ 1, AMD64_FSBASE_REGNUM, 0 },
{ 1, AMD64_GSBASE_REGNUM, 0 },
{ 0 }
};
/* This layout including fsbase and gsbase was adopted in FreeBSD
8.0. */
static const struct regcache_map_entry amd64_fbsd_mcregmap[] =
{
{ 1, REGCACHE_MAP_SKIP, 8 }, /* mc_onstack */
{ 1, AMD64_RDI_REGNUM, 0 },
{ 1, AMD64_RSI_REGNUM, 0 },
{ 1, AMD64_RDX_REGNUM, 0 },
{ 1, AMD64_RCX_REGNUM, 0 },
{ 1, AMD64_R8_REGNUM, 0 },
{ 1, AMD64_R9_REGNUM, 0 },
{ 1, AMD64_RAX_REGNUM, 0 },
{ 1, AMD64_RBX_REGNUM, 0 },
{ 1, AMD64_RBP_REGNUM, 0 },
{ 1, AMD64_R10_REGNUM, 0 },
{ 1, AMD64_R11_REGNUM, 0 },
{ 1, AMD64_R12_REGNUM, 0 },
{ 1, AMD64_R13_REGNUM, 0 },
{ 1, AMD64_R14_REGNUM, 0 },
{ 1, AMD64_R15_REGNUM, 0 },
{ 1, REGCACHE_MAP_SKIP, 4 }, /* mc_trapno */
{ 1, AMD64_FS_REGNUM, 2 },
{ 1, AMD64_GS_REGNUM, 2 },
{ 1, REGCACHE_MAP_SKIP, 8 }, /* mc_addr */
{ 1, REGCACHE_MAP_SKIP, 4 }, /* mc_flags */
{ 1, AMD64_ES_REGNUM, 2 },
{ 1, AMD64_DS_REGNUM, 2 },
{ 1, REGCACHE_MAP_SKIP, 8 }, /* mc_err */
{ 1, AMD64_RIP_REGNUM, 0 },
{ 1, AMD64_CS_REGNUM, 8 },
{ 1, AMD64_EFLAGS_REGNUM, 8 },
{ 1, AMD64_RSP_REGNUM, 0 },
{ 1, AMD64_SS_REGNUM, 8 },
{ 1, REGCACHE_MAP_SKIP, 8 }, /* mc_len */
{ 1, REGCACHE_MAP_SKIP, 8 }, /* mc_fpformat */
{ 1, REGCACHE_MAP_SKIP, 8 }, /* mc_ownedfp */
{ 64, REGCACHE_MAP_SKIP, 8 }, /* mc_fpstate */
{ 1, AMD64_FSBASE_REGNUM, 0 },
{ 1, AMD64_GSBASE_REGNUM, 0 },
{ 0 }
};
/* Register set definitions. */
const struct regset amd64_fbsd_gregset =
{
amd64_fbsd_gregmap, regcache_supply_regset, regcache_collect_regset
};
const struct regset amd64_fbsd_segbases_regset =
{
amd64_fbsd_segbases_regmap, regcache_supply_regset, regcache_collect_regset
};
/* Support for signal handlers. */
/* In a signal frame, rsp points to a 'struct sigframe' which is
defined as:
struct sigframe {
union {
__siginfohandler_t *sf_action;
__sighandler_t *sf_handler;
} sf_ahu;
ucontext_t sf_uc;
...
}
ucontext_t is defined as:
struct __ucontext {
sigset_t uc_sigmask;
mcontext_t uc_mcontext;
...
};
The mcontext_t contains the general purpose register set as well
as the floating point or XSAVE state. */
/* NB: There is an 8 byte padding hole between sf_ahu and sf_uc. */
#define AMD64_SIGFRAME_UCONTEXT_OFFSET 16
#define AMD64_UCONTEXT_MCONTEXT_OFFSET 16
#define AMD64_SIZEOF_MCONTEXT_T 800
/* Implement the "init" method of struct tramp_frame. */
static void
amd64_fbsd_sigframe_init (const struct tramp_frame *self,
const frame_info_ptr &this_frame,
struct trad_frame_cache *this_cache,
CORE_ADDR func)
{
CORE_ADDR sp = get_frame_register_unsigned (this_frame, AMD64_RSP_REGNUM);
CORE_ADDR mcontext_addr
= (sp
+ AMD64_SIGFRAME_UCONTEXT_OFFSET
+ AMD64_UCONTEXT_MCONTEXT_OFFSET);
trad_frame_set_reg_regmap (this_cache, amd64_fbsd_mcregmap, mcontext_addr,
AMD64_SIZEOF_MCONTEXT_T);
/* Don't bother with floating point or XSAVE state for now. The
current helper routines for parsing FXSAVE and XSAVE state only
work with regcaches. This could perhaps create a temporary
regcache, collect the register values from mc_fpstate and
mc_xfpustate, and then set register values in the trad_frame. */
trad_frame_set_id (this_cache, frame_id_build (sp, func));
}
static const struct tramp_frame amd64_fbsd_sigframe =
{
SIGTRAMP_FRAME,
1,
{
{0x48, ULONGEST_MAX}, /* lea SIGF_UC(%rsp),%rdi */
{0x8d, ULONGEST_MAX},
{0x7c, ULONGEST_MAX},
{0x24, ULONGEST_MAX},
{0x10, ULONGEST_MAX},
{0x6a, ULONGEST_MAX}, /* pushq $0 */
{0x00, ULONGEST_MAX},
{0x48, ULONGEST_MAX}, /* movq $SYS_sigreturn,%rax */
{0xc7, ULONGEST_MAX},
{0xc0, ULONGEST_MAX},
{0xa1, ULONGEST_MAX},
{0x01, ULONGEST_MAX},
{0x00, ULONGEST_MAX},
{0x00, ULONGEST_MAX},
{0x0f, ULONGEST_MAX}, /* syscall */
{0x05, ULONGEST_MAX},
{TRAMP_SENTINEL_INSN, ULONGEST_MAX}
},
amd64_fbsd_sigframe_init
};
/* 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)
{
x86_xsave_layout layout;
uint64_t xcr0 = i386_fbsd_core_read_xsave_info (abfd, layout);
if (xcr0 == 0)
xcr0 = X86_XSTATE_SSE_MASK;
return amd64_target_description (xcr0, true);
}
/* 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)
{
i386_gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
cb (".reg", AMD64_FBSD_SIZEOF_GREGSET, AMD64_FBSD_SIZEOF_GREGSET,
&amd64_fbsd_gregset, NULL, cb_data);
cb (".reg2", tdep->sizeof_fpregset, tdep->sizeof_fpregset, &amd64_fpregset,
NULL, cb_data);
cb (".reg-x86-segbases", AMD64_FBSD_SIZEOF_SEGBASES_REGSET,
AMD64_FBSD_SIZEOF_SEGBASES_REGSET, &amd64_fbsd_segbases_regset,
"segment bases", cb_data);
if (tdep->xsave_layout.sizeof_xsave != 0)
cb (".reg-xstate", tdep->xsave_layout.sizeof_xsave,
tdep->xsave_layout.sizeof_xsave, &amd64fbsd_xstateregset,
"XSAVE extended state", cb_data);
}
/* Implement the get_thread_local_address gdbarch method. */
static CORE_ADDR
amd64fbsd_get_thread_local_address (struct gdbarch *gdbarch, ptid_t ptid,
CORE_ADDR lm_addr, CORE_ADDR offset)
{
regcache *regcache
= get_thread_arch_regcache (current_inferior (), ptid, gdbarch);
target_fetch_registers (regcache, AMD64_FSBASE_REGNUM);
ULONGEST fsbase;
if (regcache->cooked_read (AMD64_FSBASE_REGNUM, &fsbase) != REG_VALID)
error (_("Unable to fetch %%fsbase"));
CORE_ADDR dtv_addr = fsbase + gdbarch_ptr_bit (gdbarch) / 8;
return fbsd_get_thread_local_address (gdbarch, dtv_addr, lm_addr, offset);
}
static void
amd64fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
i386_gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
/* Generic FreeBSD support. */
fbsd_init_abi (info, gdbarch);
/* Obviously FreeBSD is BSD-based. */
i386bsd_init_abi (info, gdbarch);
amd64_init_abi (info, gdbarch,
amd64_target_description (X86_XSTATE_SSE_MASK, true));
tramp_frame_prepend_unwinder (gdbarch, &amd64_fbsd_sigframe);
tdep->xsave_xcr0_offset = I386_FBSD_XSAVE_XCR0_OFFSET;
set_gdbarch_core_read_x86_xsave_layout
(gdbarch, i386_fbsd_core_read_x86_xsave_layout);
/* 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 uses SVR4-style shared libraries. */
set_solib_svr4_fetch_link_map_offsets
(gdbarch, svr4_lp64_fetch_link_map_offsets);
set_gdbarch_fetch_tls_load_module_address (gdbarch,
svr4_fetch_objfile_link_map);
set_gdbarch_get_thread_local_address (gdbarch,
amd64fbsd_get_thread_local_address);
}
void _initialize_amd64fbsd_tdep ();
void
_initialize_amd64fbsd_tdep ()
{
gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
GDB_OSABI_FREEBSD, amd64fbsd_init_abi);
}