mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-12-21 04:42:53 +08:00
8480a37e14
We currently pass frames to function by value, as `frame_info_ptr`.
This is somewhat expensive:
- the size of `frame_info_ptr` is 64 bytes, which is a bit big to pass
by value
- the constructors and destructor link/unlink the object in the global
`frame_info_ptr::frame_list` list. This is an `intrusive_list`, so
it's not so bad: it's just assigning a few points, there's no memory
allocation as if it was `std::list`, but still it's useless to do
that over and over.
As suggested by Tom Tromey, change many function signatures to accept
`const frame_info_ptr &` instead of `frame_info_ptr`.
Some functions reassign their `frame_info_ptr` parameter, like:
void
the_func (frame_info_ptr frame)
{
for (; frame != nullptr; frame = get_prev_frame (frame))
{
...
}
}
I wondered what to do about them, do I leave them as-is or change them
(and need to introduce a separate local variable that can be
re-assigned). I opted for the later for consistency. It might not be
clear why some functions take `const frame_info_ptr &` while others take
`frame_info_ptr`. Also, if a function took a `frame_info_ptr` because
it did re-assign its parameter, I doubt that we would think to change it
to `const frame_info_ptr &` should the implementation change such that
it doesn't need to take `frame_info_ptr` anymore. It seems better to
have a simple rule and apply it everywhere.
Change-Id: I59d10addef687d157f82ccf4d54f5dde9a963fd0
Approved-By: Andrew Burgess <aburgess@redhat.com>
385 lines
11 KiB
C
385 lines
11 KiB
C
/* Target-dependent code for NetBSD/mips.
|
||
|
||
Copyright (C) 2002-2024 Free Software Foundation, Inc.
|
||
|
||
Contributed by Wasabi Systems, 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 "gdbcore.h"
|
||
#include "regcache.h"
|
||
#include "regset.h"
|
||
#include "target.h"
|
||
#include "value.h"
|
||
#include "osabi.h"
|
||
|
||
#include "netbsd-tdep.h"
|
||
#include "mips-netbsd-tdep.h"
|
||
#include "mips-tdep.h"
|
||
|
||
#include "solib-svr4.h"
|
||
|
||
/* Shorthand for some register numbers used below. */
|
||
#define MIPS_PC_REGNUM MIPS_EMBED_PC_REGNUM
|
||
#define MIPS_FP0_REGNUM MIPS_EMBED_FP0_REGNUM
|
||
#define MIPS_FSR_REGNUM MIPS_EMBED_FP0_REGNUM + 32
|
||
|
||
/* Core file support. */
|
||
|
||
/* Number of registers in `struct reg' from <machine/reg.h>. */
|
||
#define MIPSNBSD_NUM_GREGS 38
|
||
|
||
/* Number of registers in `struct fpreg' from <machine/reg.h>. */
|
||
#define MIPSNBSD_NUM_FPREGS 33
|
||
|
||
/* 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
|
||
mipsnbsd_supply_fpregset (const struct regset *regset,
|
||
struct regcache *regcache,
|
||
int regnum, const void *fpregs, size_t len)
|
||
{
|
||
size_t regsize = mips_isa_regsize (regcache->arch ());
|
||
const char *regs = (const char *) fpregs;
|
||
int i;
|
||
|
||
gdb_assert (len >= MIPSNBSD_NUM_FPREGS * regsize);
|
||
|
||
for (i = MIPS_FP0_REGNUM; i <= MIPS_FSR_REGNUM; i++)
|
||
{
|
||
if (regnum == i || regnum == -1)
|
||
regcache->raw_supply (i, regs + (i - MIPS_FP0_REGNUM) * 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
|
||
mipsnbsd_supply_gregset (const struct regset *regset,
|
||
struct regcache *regcache, int regnum,
|
||
const void *gregs, size_t len)
|
||
{
|
||
size_t regsize = mips_isa_regsize (regcache->arch ());
|
||
const char *regs = (const char *) gregs;
|
||
int i;
|
||
|
||
gdb_assert (len >= MIPSNBSD_NUM_GREGS * regsize);
|
||
|
||
for (i = 0; i <= MIPS_PC_REGNUM; i++)
|
||
{
|
||
if (regnum == i || regnum == -1)
|
||
regcache->raw_supply (i, regs + i * regsize);
|
||
}
|
||
|
||
if (len >= (MIPSNBSD_NUM_GREGS + MIPSNBSD_NUM_FPREGS) * regsize)
|
||
{
|
||
regs += MIPSNBSD_NUM_GREGS * regsize;
|
||
len -= MIPSNBSD_NUM_GREGS * regsize;
|
||
mipsnbsd_supply_fpregset (regset, regcache, regnum, regs, len);
|
||
}
|
||
}
|
||
|
||
/* NetBSD/mips register sets. */
|
||
|
||
static const struct regset mipsnbsd_gregset =
|
||
{
|
||
NULL,
|
||
mipsnbsd_supply_gregset,
|
||
NULL,
|
||
REGSET_VARIABLE_SIZE
|
||
};
|
||
|
||
static const struct regset mipsnbsd_fpregset =
|
||
{
|
||
NULL,
|
||
mipsnbsd_supply_fpregset
|
||
};
|
||
|
||
/* Iterate over core file register note sections. */
|
||
|
||
static void
|
||
mipsnbsd_iterate_over_regset_sections (struct gdbarch *gdbarch,
|
||
iterate_over_regset_sections_cb *cb,
|
||
void *cb_data,
|
||
const struct regcache *regcache)
|
||
{
|
||
size_t regsize = mips_isa_regsize (gdbarch);
|
||
|
||
cb (".reg", MIPSNBSD_NUM_GREGS * regsize, MIPSNBSD_NUM_GREGS * regsize,
|
||
&mipsnbsd_gregset, NULL, cb_data);
|
||
cb (".reg2", MIPSNBSD_NUM_FPREGS * regsize, MIPSNBSD_NUM_FPREGS * regsize,
|
||
&mipsnbsd_fpregset, NULL, cb_data);
|
||
}
|
||
|
||
|
||
/* Conveniently, GDB uses the same register numbering as the
|
||
ptrace register structure used by NetBSD/mips. */
|
||
|
||
void
|
||
mipsnbsd_supply_reg (struct regcache *regcache, const char *regs, int regno)
|
||
{
|
||
struct gdbarch *gdbarch = regcache->arch ();
|
||
int i;
|
||
|
||
for (i = 0; i <= gdbarch_pc_regnum (gdbarch); i++)
|
||
{
|
||
if (regno == i || regno == -1)
|
||
{
|
||
if (gdbarch_cannot_fetch_register (gdbarch, i))
|
||
regcache->raw_supply (i, NULL);
|
||
else
|
||
regcache->raw_supply
|
||
(i, regs + (i * mips_isa_regsize (gdbarch)));
|
||
}
|
||
}
|
||
}
|
||
|
||
void
|
||
mipsnbsd_fill_reg (const struct regcache *regcache, char *regs, int regno)
|
||
{
|
||
struct gdbarch *gdbarch = regcache->arch ();
|
||
int i;
|
||
|
||
for (i = 0; i <= gdbarch_pc_regnum (gdbarch); i++)
|
||
if ((regno == i || regno == -1)
|
||
&& ! gdbarch_cannot_store_register (gdbarch, i))
|
||
regcache->raw_collect (i, regs + (i * mips_isa_regsize (gdbarch)));
|
||
}
|
||
|
||
void
|
||
mipsnbsd_supply_fpreg (struct regcache *regcache,
|
||
const char *fpregs, int regno)
|
||
{
|
||
struct gdbarch *gdbarch = regcache->arch ();
|
||
int i;
|
||
|
||
for (i = gdbarch_fp0_regnum (gdbarch);
|
||
i <= mips_regnum (gdbarch)->fp_implementation_revision;
|
||
i++)
|
||
{
|
||
if (regno == i || regno == -1)
|
||
{
|
||
if (gdbarch_cannot_fetch_register (gdbarch, i))
|
||
regcache->raw_supply (i, NULL);
|
||
else
|
||
regcache->raw_supply (i,
|
||
fpregs
|
||
+ ((i - gdbarch_fp0_regnum (gdbarch))
|
||
* mips_isa_regsize (gdbarch)));
|
||
}
|
||
}
|
||
}
|
||
|
||
void
|
||
mipsnbsd_fill_fpreg (const struct regcache *regcache, char *fpregs, int regno)
|
||
{
|
||
struct gdbarch *gdbarch = regcache->arch ();
|
||
int i;
|
||
|
||
for (i = gdbarch_fp0_regnum (gdbarch);
|
||
i <= mips_regnum (gdbarch)->fp_control_status;
|
||
i++)
|
||
if ((regno == i || regno == -1)
|
||
&& ! gdbarch_cannot_store_register (gdbarch, i))
|
||
regcache->raw_collect
|
||
(i, (fpregs + ((i - gdbarch_fp0_regnum (gdbarch))
|
||
* mips_isa_regsize (gdbarch))));
|
||
}
|
||
|
||
#if 0
|
||
|
||
/* Under NetBSD/mips, signal handler invocations can be identified by the
|
||
designated code sequence that is used to return from a signal handler.
|
||
In particular, the return address of a signal handler points to the
|
||
following code sequence:
|
||
|
||
addu a0, sp, 16
|
||
li v0, 295 # __sigreturn14
|
||
syscall
|
||
|
||
Each instruction has a unique encoding, so we simply attempt to match
|
||
the instruction the PC is pointing to with any of the above instructions.
|
||
If there is a hit, we know the offset to the start of the designated
|
||
sequence and can then check whether we really are executing in the
|
||
signal trampoline. If not, -1 is returned, otherwise the offset from the
|
||
start of the return sequence is returned. */
|
||
|
||
#define RETCODE_NWORDS 3
|
||
#define RETCODE_SIZE (RETCODE_NWORDS * 4)
|
||
|
||
static const unsigned char sigtramp_retcode_mipsel[RETCODE_SIZE] =
|
||
{
|
||
0x10, 0x00, 0xa4, 0x27, /* addu a0, sp, 16 */
|
||
0x27, 0x01, 0x02, 0x24, /* li v0, 295 */
|
||
0x0c, 0x00, 0x00, 0x00, /* syscall */
|
||
};
|
||
|
||
static const unsigned char sigtramp_retcode_mipseb[RETCODE_SIZE] =
|
||
{
|
||
0x27, 0xa4, 0x00, 0x10, /* addu a0, sp, 16 */
|
||
0x24, 0x02, 0x01, 0x27, /* li v0, 295 */
|
||
0x00, 0x00, 0x00, 0x0c, /* syscall */
|
||
};
|
||
|
||
#endif
|
||
|
||
/* Figure out where the longjmp will land. We expect that we have
|
||
just entered longjmp and haven't yet setup the stack frame, so the
|
||
args are still in the argument regs. MIPS_A0_REGNUM points at the
|
||
jmp_buf structure from which we extract the PC that we will land
|
||
at. The PC is copied into *pc. This routine returns true on
|
||
success. */
|
||
|
||
#define NBSD_MIPS_JB_PC (2 * 4)
|
||
#define NBSD_MIPS_JB_ELEMENT_SIZE(gdbarch) mips_isa_regsize (gdbarch)
|
||
#define NBSD_MIPS_JB_OFFSET(gdbarch) (NBSD_MIPS_JB_PC * \
|
||
NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch))
|
||
|
||
static int
|
||
mipsnbsd_get_longjmp_target (const frame_info_ptr &frame, CORE_ADDR *pc)
|
||
{
|
||
struct gdbarch *gdbarch = get_frame_arch (frame);
|
||
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
||
CORE_ADDR jb_addr;
|
||
gdb_byte *buf;
|
||
|
||
buf = (gdb_byte *) alloca (NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch));
|
||
|
||
jb_addr = get_frame_register_unsigned (frame, MIPS_A0_REGNUM);
|
||
|
||
if (target_read_memory (jb_addr + NBSD_MIPS_JB_OFFSET (gdbarch), buf,
|
||
NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch)))
|
||
return 0;
|
||
|
||
*pc = extract_unsigned_integer (buf, NBSD_MIPS_JB_ELEMENT_SIZE (gdbarch),
|
||
byte_order);
|
||
return 1;
|
||
}
|
||
|
||
static int
|
||
mipsnbsd_cannot_fetch_register (struct gdbarch *gdbarch, int regno)
|
||
{
|
||
return (regno == MIPS_ZERO_REGNUM
|
||
|| regno == mips_regnum (gdbarch)->fp_implementation_revision);
|
||
}
|
||
|
||
static int
|
||
mipsnbsd_cannot_store_register (struct gdbarch *gdbarch, int regno)
|
||
{
|
||
return (regno == MIPS_ZERO_REGNUM
|
||
|| regno == mips_regnum (gdbarch)->fp_implementation_revision);
|
||
}
|
||
|
||
/* Shared library support. */
|
||
|
||
/* NetBSD/mips uses a slightly different `struct link_map' than the
|
||
other NetBSD platforms. */
|
||
|
||
static struct link_map_offsets *
|
||
mipsnbsd_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.r_next_offset = -1;
|
||
|
||
/* Everything we need is in the first 24 bytes. */
|
||
lmo.link_map_size = 24;
|
||
lmo.l_addr_offset = 4;
|
||
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 *
|
||
mipsnbsd_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.r_next_offset = -1;
|
||
|
||
/* Everything we need is in the first 40 bytes. */
|
||
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
|
||
mipsnbsd_init_abi (struct gdbarch_info info,
|
||
struct gdbarch *gdbarch)
|
||
{
|
||
nbsd_init_abi (info, gdbarch);
|
||
|
||
set_gdbarch_iterate_over_regset_sections
|
||
(gdbarch, mipsnbsd_iterate_over_regset_sections);
|
||
|
||
set_gdbarch_get_longjmp_target (gdbarch, mipsnbsd_get_longjmp_target);
|
||
|
||
set_gdbarch_cannot_fetch_register (gdbarch, mipsnbsd_cannot_fetch_register);
|
||
set_gdbarch_cannot_store_register (gdbarch, mipsnbsd_cannot_store_register);
|
||
|
||
set_gdbarch_software_single_step (gdbarch, mips_software_single_step);
|
||
|
||
/* NetBSD/mips has SVR4-style shared libraries. */
|
||
set_solib_svr4_fetch_link_map_offsets
|
||
(gdbarch, (gdbarch_ptr_bit (gdbarch) == 32 ?
|
||
mipsnbsd_ilp32_fetch_link_map_offsets :
|
||
mipsnbsd_lp64_fetch_link_map_offsets));
|
||
}
|
||
|
||
void _initialize_mipsnbsd_tdep ();
|
||
void
|
||
_initialize_mipsnbsd_tdep ()
|
||
{
|
||
gdbarch_register_osabi (bfd_arch_mips, 0, GDB_OSABI_NETBSD,
|
||
mipsnbsd_init_abi);
|
||
}
|