/* Target-dependent code for FreeBSD/mips.
Copyright (C) 2017-2020 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 <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "osabi.h"
#include "regset.h"
#include "trad-frame.h"
#include "tramp-frame.h"
#include "fbsd-tdep.h"
#include "mips-tdep.h"
#include "mips-fbsd-tdep.h"
#include "solib-svr4.h"
/* Core file support. */
/* Number of registers in `struct reg' from <machine/reg.h>. The
first 38 follow the standard MIPS layout. The 39th holds
IC_INT_REG on RM7K and RM9K processors. The 40th is a dummy for
padding. */
#define MIPS_FBSD_NUM_GREGS 40
/* Number of registers in `struct fpreg' from <machine/reg.h>. The
first 32 hold floating point registers. 33 holds the FSR. The
34th holds FIR on FreeBSD 12.0 and newer kernels. On older kernels
it was a zero-filled dummy for padding. */
#define MIPS_FBSD_NUM_FPREGS 34
/* Supply a single register. The register size might not match, so use
regcache->raw_supply_integer (). */
static void
mips_fbsd_supply_reg (struct regcache *regcache, int regnum, const void *addr,
size_t len)
{
regcache->raw_supply_integer (regnum, (const gdb_byte *) addr, len, true);
}
/* Collect a single register. The register size might not match, so use
regcache->raw_collect_integer (). */
static void
mips_fbsd_collect_reg (const struct regcache *regcache, int regnum, void *addr,
size_t len)
{
regcache->raw_collect_integer (regnum, (gdb_byte *) addr, len, true);
}
/* Supply the floating-point registers stored in FPREGS to REGCACHE.
Each floating-point register in FPREGS is REGSIZE bytes in
length. */
void
mips_fbsd_supply_fpregs (struct regcache *regcache, int regnum,
const void *fpregs, size_t regsize)
{
struct gdbarch *gdbarch = regcache->arch ();
const gdb_byte *regs = (const gdb_byte *) fpregs;
int i, fp0num;
fp0num = mips_regnum (gdbarch)->fp0;
for (i = 0; i <= 32; i++)
if (regnum == fp0num + i || regnum == -1)
mips_fbsd_supply_reg (regcache, fp0num + i,
regs + i * regsize, regsize);
if (regnum == mips_regnum (gdbarch)->fp_control_status || regnum == -1)
mips_fbsd_supply_reg (regcache, mips_regnum (gdbarch)->fp_control_status,
regs + 32 * regsize, regsize);
if ((regnum == mips_regnum (gdbarch)->fp_implementation_revision
|| regnum == -1)
&& extract_unsigned_integer (regs + 33 * regsize, regsize,
gdbarch_byte_order (gdbarch)) != 0)
mips_fbsd_supply_reg (regcache,
mips_regnum (gdbarch)->fp_implementation_revision,
regs + 33 * regsize, regsize);
}
/* Supply the general-purpose registers stored in GREGS to REGCACHE.
Each general-purpose register in GREGS is REGSIZE bytes in
length. */
void
mips_fbsd_supply_gregs (struct regcache *regcache, int regnum,
const void *gregs, size_t regsize)
{
struct gdbarch *gdbarch = regcache->arch ();
const gdb_byte *regs = (const gdb_byte *) gregs;
int i;
for (i = 0; i <= mips_regnum (gdbarch)->pc; i++)
if (regnum == i || regnum == -1)
mips_fbsd_supply_reg (regcache, i, regs + i * regsize, regsize);
}
/* Collect the floating-point registers from REGCACHE and store them
in FPREGS. Each floating-point register in FPREGS is REGSIZE bytes
in length. */
void
mips_fbsd_collect_fpregs (const struct regcache *regcache, int regnum,
void *fpregs, size_t regsize)
{
struct gdbarch *gdbarch = regcache->arch ();
gdb_byte *regs = (gdb_byte *) fpregs;
int i, fp0num;
fp0num = mips_regnum (gdbarch)->fp0;
for (i = 0; i < 32; i++)
if (regnum == fp0num + i || regnum == -1)
mips_fbsd_collect_reg (regcache, fp0num + i,
regs + i * regsize, regsize);
if (regnum == mips_regnum (gdbarch)->fp_control_status || regnum == -1)
mips_fbsd_collect_reg (regcache, mips_regnum (gdbarch)->fp_control_status,
regs + 32 * regsize, regsize);
if (regnum == mips_regnum (gdbarch)->fp_implementation_revision
|| regnum == -1)
mips_fbsd_collect_reg (regcache,
mips_regnum (gdbarch)->fp_implementation_revision,
regs + 33 * regsize, regsize);
}
/* Collect the general-purpose registers from REGCACHE and store them
in GREGS. Each general-purpose register in GREGS is REGSIZE bytes
in length. */
void
mips_fbsd_collect_gregs (const struct regcache *regcache, int regnum,
void *gregs, size_t regsize)
{
struct gdbarch *gdbarch = regcache->arch ();
gdb_byte *regs = (gdb_byte *) gregs;
int i;
for (i = 0; i <= mips_regnum (gdbarch)->pc; i++)
if (regnum == i || regnum == -1)
mips_fbsd_collect_reg (regcache, i, regs + i * regsize, regsize);
}
/* Supply register REGNUM from the buffer specified by FPREGS and LEN
in the floating-point register set REGSET to register cache
REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
static void
mips_fbsd_supply_fpregset (const struct regset *regset,
struct regcache *regcache,
int regnum, const void *fpregs, size_t len)
{
size_t regsize = mips_abi_regsize (regcache->arch ());
gdb_assert (len >= MIPS_FBSD_NUM_FPREGS * regsize);
mips_fbsd_supply_fpregs (regcache, regnum, fpregs, regsize);
}
/* Collect register REGNUM from the register cache REGCACHE and store
it in the buffer specified by FPREGS and LEN in the floating-point
register set REGSET. If REGNUM is -1, do this for all registers in
REGSET. */
static void
mips_fbsd_collect_fpregset (const struct regset *regset,
const struct regcache *regcache,
int regnum, void *fpregs, size_t len)
{
size_t regsize = mips_abi_regsize (regcache->arch ());
gdb_assert (len >= MIPS_FBSD_NUM_FPREGS * regsize);
mips_fbsd_collect_fpregs (regcache, regnum, fpregs, regsize);
}
/* Supply register REGNUM from the buffer specified by GREGS and LEN
in the general-purpose register set REGSET to register cache
REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
static void
mips_fbsd_supply_gregset (const struct regset *regset,
struct regcache *regcache, int regnum,
const void *gregs, size_t len)
{
size_t regsize = mips_abi_regsize (regcache->arch ());
gdb_assert (len >= MIPS_FBSD_NUM_GREGS * regsize);
mips_fbsd_supply_gregs (regcache, regnum, gregs, regsize);
}
/* Collect register REGNUM from the register cache REGCACHE and store
it in the buffer specified by GREGS and LEN in the general-purpose
register set REGSET. If REGNUM is -1, do this for all registers in
REGSET. */
static void
mips_fbsd_collect_gregset (const struct regset *regset,
const struct regcache *regcache,
int regnum, void *gregs, size_t len)
{
size_t regsize = mips_abi_regsize (regcache->arch ());
gdb_assert (len >= MIPS_FBSD_NUM_GREGS * regsize);
mips_fbsd_collect_gregs (regcache, regnum, gregs, regsize);
}
/* FreeBSD/mips register sets. */
static const struct regset mips_fbsd_gregset =
{
NULL,
mips_fbsd_supply_gregset,
mips_fbsd_collect_gregset,
};
static const struct regset mips_fbsd_fpregset =
{
NULL,
mips_fbsd_supply_fpregset,
mips_fbsd_collect_fpregset,
};
/* Iterate over core file register note sections. */
static void
mips_fbsd_iterate_over_regset_sections (struct gdbarch *gdbarch,
iterate_over_regset_sections_cb *cb,
void *cb_data,
const struct regcache *regcache)
{
size_t regsize = mips_abi_regsize (gdbarch);
cb (".reg", MIPS_FBSD_NUM_GREGS * regsize, MIPS_FBSD_NUM_GREGS * regsize,
&mips_fbsd_gregset, NULL, cb_data);
cb (".reg2", MIPS_FBSD_NUM_FPREGS * regsize, MIPS_FBSD_NUM_FPREGS * regsize,
&mips_fbsd_fpregset, NULL, cb_data);
}
/* Signal trampoline support. */
#define FBSD_SYS_sigreturn 417
#define MIPS_INST_LI_V0_SIGRETURN 0x24020000 + FBSD_SYS_sigreturn
#define MIPS_INST_SYSCALL 0x0000000c
#define MIPS_INST_BREAK 0x0000000d
#define O32_SIGFRAME_UCONTEXT_OFFSET (16)
#define O32_SIGSET_T_SIZE (16)
#define O32_UCONTEXT_ONSTACK (O32_SIGSET_T_SIZE)
#define O32_UCONTEXT_PC (O32_UCONTEXT_ONSTACK + 4)
#define O32_UCONTEXT_REGS (O32_UCONTEXT_PC + 4)
#define O32_UCONTEXT_SR (O32_UCONTEXT_REGS + 4 * 32)
#define O32_UCONTEXT_LO (O32_UCONTEXT_SR + 4)
#define O32_UCONTEXT_HI (O32_UCONTEXT_LO + 4)
#define O32_UCONTEXT_FPUSED (O32_UCONTEXT_HI + 4)
#define O32_UCONTEXT_FPREGS (O32_UCONTEXT_FPUSED + 4)
#define O32_UCONTEXT_REG_SIZE 4
static void
mips_fbsd_sigframe_init (const struct tramp_frame *self,
struct frame_info *this_frame,
struct trad_frame_cache *cache,
CORE_ADDR func)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR sp, ucontext_addr, addr;
int regnum;
gdb_byte buf[4];
/* We find the appropriate instance of `ucontext_t' at a
fixed offset in the signal frame. */
sp = get_frame_register_signed (this_frame,
MIPS_SP_REGNUM + gdbarch_num_regs (gdbarch));
ucontext_addr = sp + O32_SIGFRAME_UCONTEXT_OFFSET;
/* PC. */
regnum = mips_regnum (gdbarch)->pc;
trad_frame_set_reg_addr (cache,
regnum + gdbarch_num_regs (gdbarch),
ucontext_addr + O32_UCONTEXT_PC);
/* GPRs. */
for (regnum = MIPS_ZERO_REGNUM, addr = ucontext_addr + O32_UCONTEXT_REGS;
regnum <= MIPS_RA_REGNUM; regnum++, addr += O32_UCONTEXT_REG_SIZE)
trad_frame_set_reg_addr (cache,
regnum + gdbarch_num_regs (gdbarch),
addr);
regnum = MIPS_PS_REGNUM;
trad_frame_set_reg_addr (cache,
regnum + gdbarch_num_regs (gdbarch),
ucontext_addr + O32_UCONTEXT_SR);
/* HI and LO. */
regnum = mips_regnum (gdbarch)->lo;
trad_frame_set_reg_addr (cache,
regnum + gdbarch_num_regs (gdbarch),
ucontext_addr + O32_UCONTEXT_LO);
regnum = mips_regnum (gdbarch)->hi;
trad_frame_set_reg_addr (cache,
regnum + gdbarch_num_regs (gdbarch),
ucontext_addr + O32_UCONTEXT_HI);
if (target_read_memory (ucontext_addr + O32_UCONTEXT_FPUSED, buf, 4) == 0
&& extract_unsigned_integer (buf, 4, byte_order) != 0)
{
for (regnum = 0, addr = ucontext_addr + O32_UCONTEXT_FPREGS;
regnum < 32; regnum++, addr += O32_UCONTEXT_REG_SIZE)
trad_frame_set_reg_addr (cache,
regnum + gdbarch_fp0_regnum (gdbarch),
addr);
trad_frame_set_reg_addr (cache, mips_regnum (gdbarch)->fp_control_status,
addr);
}
trad_frame_set_id (cache, frame_id_build (sp, func));
}
#define MIPS_INST_ADDIU_A0_SP_O32 (0x27a40000 \
+ O32_SIGFRAME_UCONTEXT_OFFSET)
static const struct tramp_frame mips_fbsd_sigframe =
{
SIGTRAMP_FRAME,
MIPS_INSN32_SIZE,
{
{ MIPS_INST_ADDIU_A0_SP_O32, ULONGEST_MAX }, /* addiu a0, sp, SIGF_UC */
{ MIPS_INST_LI_V0_SIGRETURN, ULONGEST_MAX }, /* li v0, SYS_sigreturn */
{ MIPS_INST_SYSCALL, ULONGEST_MAX }, /* syscall */
{ MIPS_INST_BREAK, ULONGEST_MAX }, /* break */
{ TRAMP_SENTINEL_INSN, ULONGEST_MAX }
},
mips_fbsd_sigframe_init
};
#define N64_SIGFRAME_UCONTEXT_OFFSET (32)
#define N64_SIGSET_T_SIZE (16)
#define N64_UCONTEXT_ONSTACK (N64_SIGSET_T_SIZE)
#define N64_UCONTEXT_PC (N64_UCONTEXT_ONSTACK + 8)
#define N64_UCONTEXT_REGS (N64_UCONTEXT_PC + 8)
#define N64_UCONTEXT_SR (N64_UCONTEXT_REGS + 8 * 32)
#define N64_UCONTEXT_LO (N64_UCONTEXT_SR + 8)
#define N64_UCONTEXT_HI (N64_UCONTEXT_LO + 8)
#define N64_UCONTEXT_FPUSED (N64_UCONTEXT_HI + 8)
#define N64_UCONTEXT_FPREGS (N64_UCONTEXT_FPUSED + 8)
#define N64_UCONTEXT_REG_SIZE 8
static void
mips64_fbsd_sigframe_init (const struct tramp_frame *self,
struct frame_info *this_frame,
struct trad_frame_cache *cache,
CORE_ADDR func)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR sp, ucontext_addr, addr;
int regnum;
gdb_byte buf[4];
/* We find the appropriate instance of `ucontext_t' at a
fixed offset in the signal frame. */
sp = get_frame_register_signed (this_frame,
MIPS_SP_REGNUM + gdbarch_num_regs (gdbarch));
ucontext_addr = sp + N64_SIGFRAME_UCONTEXT_OFFSET;
/* PC. */
regnum = mips_regnum (gdbarch)->pc;
trad_frame_set_reg_addr (cache,
regnum + gdbarch_num_regs (gdbarch),
ucontext_addr + N64_UCONTEXT_PC);
/* GPRs. */
for (regnum = MIPS_ZERO_REGNUM, addr = ucontext_addr + N64_UCONTEXT_REGS;
regnum <= MIPS_RA_REGNUM; regnum++, addr += N64_UCONTEXT_REG_SIZE)
trad_frame_set_reg_addr (cache,
regnum + gdbarch_num_regs (gdbarch),
addr);
regnum = MIPS_PS_REGNUM;
trad_frame_set_reg_addr (cache,
regnum + gdbarch_num_regs (gdbarch),
ucontext_addr + N64_UCONTEXT_SR);
/* HI and LO. */
regnum = mips_regnum (gdbarch)->lo;
trad_frame_set_reg_addr (cache,
regnum + gdbarch_num_regs (gdbarch),
ucontext_addr + N64_UCONTEXT_LO);
regnum = mips_regnum (gdbarch)->hi;
trad_frame_set_reg_addr (cache,
regnum + gdbarch_num_regs (gdbarch),
ucontext_addr + N64_UCONTEXT_HI);
if (target_read_memory (ucontext_addr + N64_UCONTEXT_FPUSED, buf, 4) == 0
&& extract_unsigned_integer (buf, 4, byte_order) != 0)
{
for (regnum = 0, addr = ucontext_addr + N64_UCONTEXT_FPREGS;
regnum < 32; regnum++, addr += N64_UCONTEXT_REG_SIZE)
trad_frame_set_reg_addr (cache,
regnum + gdbarch_fp0_regnum (gdbarch),
addr);
trad_frame_set_reg_addr (cache, mips_regnum (gdbarch)->fp_control_status,
addr);
}
trad_frame_set_id (cache, frame_id_build (sp, func));
}
#define MIPS_INST_ADDIU_A0_SP_N32 (0x27a40000 \
+ N64_SIGFRAME_UCONTEXT_OFFSET)
static const struct tramp_frame mipsn32_fbsd_sigframe =
{
SIGTRAMP_FRAME,
MIPS_INSN32_SIZE,
{
{ MIPS_INST_ADDIU_A0_SP_N32, ULONGEST_MAX }, /* addiu a0, sp, SIGF_UC */
{ MIPS_INST_LI_V0_SIGRETURN, ULONGEST_MAX }, /* li v0, SYS_sigreturn */
{ MIPS_INST_SYSCALL, ULONGEST_MAX }, /* syscall */
{ MIPS_INST_BREAK, ULONGEST_MAX }, /* break */
{ TRAMP_SENTINEL_INSN, ULONGEST_MAX }
},
mips64_fbsd_sigframe_init
};
#define MIPS_INST_DADDIU_A0_SP_N64 (0x67a40000 \
+ N64_SIGFRAME_UCONTEXT_OFFSET)
static const struct tramp_frame mips64_fbsd_sigframe =
{
SIGTRAMP_FRAME,
MIPS_INSN32_SIZE,
{
{ MIPS_INST_DADDIU_A0_SP_N64, ULONGEST_MAX }, /* daddiu a0, sp, SIGF_UC */
{ MIPS_INST_LI_V0_SIGRETURN, ULONGEST_MAX }, /* li v0, SYS_sigreturn */
{ MIPS_INST_SYSCALL, ULONGEST_MAX }, /* syscall */
{ MIPS_INST_BREAK, ULONGEST_MAX }, /* break */
{ TRAMP_SENTINEL_INSN, ULONGEST_MAX }
},
mips64_fbsd_sigframe_init
};
/* Shared library support. */
/* FreeBSD/mips can use an alternate routine in the runtime linker to
resolve functions. */
static CORE_ADDR
mips_fbsd_skip_solib_resolver (struct gdbarch *gdbarch, CORE_ADDR pc)
{
struct bound_minimal_symbol msym
= lookup_bound_minimal_symbol ("_mips_rtld_bind");
if (msym.minsym != nullptr && BMSYMBOL_VALUE_ADDRESS (msym) == pc)
return frame_unwind_caller_pc (get_current_frame ());
return fbsd_skip_solib_resolver (gdbarch, pc);
}
/* FreeBSD/mips uses a slightly different `struct link_map' than the
other FreeBSD platforms as it includes an additional `l_off'
member. */
static struct link_map_offsets *
mips_fbsd_ilp32_fetch_link_map_offsets (void)
{
static struct link_map_offsets lmo;
static struct link_map_offsets *lmp = NULL;
if (lmp == NULL)
{
lmp = &lmo;
lmo.r_version_offset = 0;
lmo.r_version_size = 4;
lmo.r_map_offset = 4;
lmo.r_brk_offset = 8;
lmo.r_ldsomap_offset = -1;
lmo.link_map_size = 24;
lmo.l_addr_offset = 0;
lmo.l_name_offset = 8;
lmo.l_ld_offset = 12;
lmo.l_next_offset = 16;
lmo.l_prev_offset = 20;
}
return lmp;
}
static struct link_map_offsets *
mips_fbsd_lp64_fetch_link_map_offsets (void)
{
static struct link_map_offsets lmo;
static struct link_map_offsets *lmp = NULL;
if (lmp == NULL)
{
lmp = &lmo;
lmo.r_version_offset = 0;
lmo.r_version_size = 4;
lmo.r_map_offset = 8;
lmo.r_brk_offset = 16;
lmo.r_ldsomap_offset = -1;
lmo.link_map_size = 48;
lmo.l_addr_offset = 0;
lmo.l_name_offset = 16;
lmo.l_ld_offset = 24;
lmo.l_next_offset = 32;
lmo.l_prev_offset = 40;
}
return lmp;
}
static void
mips_fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
enum mips_abi abi = mips_abi (gdbarch);
/* Generic FreeBSD support. */
fbsd_init_abi (info, gdbarch);
set_gdbarch_software_single_step (gdbarch, mips_software_single_step);
switch (abi)
{
case MIPS_ABI_O32:
tramp_frame_prepend_unwinder (gdbarch, &mips_fbsd_sigframe);
break;
case MIPS_ABI_N32:
tramp_frame_prepend_unwinder (gdbarch, &mipsn32_fbsd_sigframe);
break;
case MIPS_ABI_N64:
tramp_frame_prepend_unwinder (gdbarch, &mips64_fbsd_sigframe);
break;
}
set_gdbarch_iterate_over_regset_sections
(gdbarch, mips_fbsd_iterate_over_regset_sections);
set_gdbarch_skip_solib_resolver (gdbarch, mips_fbsd_skip_solib_resolver);
/* FreeBSD/mips has SVR4-style shared libraries. */
set_solib_svr4_fetch_link_map_offsets
(gdbarch, (gdbarch_ptr_bit (gdbarch) == 32 ?
mips_fbsd_ilp32_fetch_link_map_offsets :
mips_fbsd_lp64_fetch_link_map_offsets));
}
void _initialize_mips_fbsd_tdep ();
void
_initialize_mips_fbsd_tdep ()
{
gdbarch_register_osabi (bfd_arch_mips, 0, GDB_OSABI_FREEBSD,
mips_fbsd_init_abi);
}