blob: 90988cdfdac0094dffe8f7eb02441823f75ee597 [file] [log] [blame]
/* Target-dependent code for SDE on MIPS processors.
Copyright (C) 2014-2024 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 <http://www.gnu.org/licenses/>. */
#include "osabi.h"
#include "elf-bfd.h"
#include "symtab.h"
#include "frame.h"
#include "frame-unwind.h"
#include "frame-base.h"
#include "trad-frame.h"
#include "mips-tdep.h"
/* Fill in the register cache *THIS_CACHE for THIS_FRAME for use
in the SDE frame unwinder. */
static struct trad_frame_cache *
mips_sde_frame_cache (const frame_info_ptr &this_frame, void **this_cache)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
const struct mips_regnum *regs = mips_regnum (gdbarch);
const int sizeof_reg_t = mips_abi_regsize (gdbarch);
enum mips_abi abi = mips_abi (gdbarch);
struct trad_frame_cache *cache;
CORE_ADDR xcpt_frame;
CORE_ADDR start_addr;
CORE_ADDR stack_addr;
CORE_ADDR pc;
int i;
if (*this_cache != NULL)
return (struct trad_frame_cache *) *this_cache;
cache = trad_frame_cache_zalloc (this_frame);
*this_cache = cache;
/* The previous registers are held in struct xcptcontext
which is at $sp+offs
struct xcptcontext {
reg_t sr; CP0 Status
reg_t cr; CP0 Cause
reg_t epc; CP0 EPC
reg_t vaddr; CP0 BadVAddr
reg_t regs[32]; General registers
reg_t mdlo; LO
reg_t mdhi; HI
reg_t mdex; ACX
...
};
*/
stack_addr = get_frame_register_signed (this_frame,
gdbarch_sp_regnum (gdbarch));
switch (abi)
{
case MIPS_ABI_O32:
/* 40: XCPTCONTEXT
24: xcpt_gen() argspace (16 bytes)
16: _xcptcall() saved ra, rounded up ( 8 bytes)
00: _xcptcall() argspace (16 bytes) */
xcpt_frame = stack_addr + 40;
break;
case MIPS_ABI_N32:
case MIPS_ABI_N64:
default: /* Wild guess. */
/* 16: XCPTCONTEXT
16: xcpt_gen() argspace ( 0 bytes)
00: _xcptcall() saved ra, rounded up (16 bytes) */
xcpt_frame = stack_addr + 16;
break;
}
trad_frame_set_reg_addr (cache,
MIPS_PS_REGNUM + gdbarch_num_regs (gdbarch),
xcpt_frame + 0 * sizeof_reg_t);
trad_frame_set_reg_addr (cache,
regs->cause + gdbarch_num_regs (gdbarch),
xcpt_frame + 1 * sizeof_reg_t);
trad_frame_set_reg_addr (cache,
regs->pc + gdbarch_num_regs (gdbarch),
xcpt_frame + 2 * sizeof_reg_t);
trad_frame_set_reg_addr (cache,
regs->badvaddr + gdbarch_num_regs (gdbarch),
xcpt_frame + 3 * sizeof_reg_t);
for (i = 0; i < MIPS_NUMREGS; i++)
trad_frame_set_reg_addr (cache,
i + MIPS_ZERO_REGNUM + gdbarch_num_regs (gdbarch),
xcpt_frame + (4 + i) * sizeof_reg_t);
trad_frame_set_reg_addr (cache,
regs->lo + gdbarch_num_regs (gdbarch),
xcpt_frame + 36 * sizeof_reg_t);
trad_frame_set_reg_addr (cache,
regs->hi + gdbarch_num_regs (gdbarch),
xcpt_frame + 37 * sizeof_reg_t);
pc = get_frame_pc (this_frame);
find_pc_partial_function (pc, NULL, &start_addr, NULL);
trad_frame_set_id (cache, frame_id_build (start_addr, stack_addr));
return cache;
}
/* Implement the this_id function for the SDE frame unwinder. */
static void
mips_sde_frame_this_id (const frame_info_ptr &this_frame, void **this_cache,
struct frame_id *this_id)
{
struct trad_frame_cache *this_trad_cache
= mips_sde_frame_cache (this_frame, this_cache);
trad_frame_get_id (this_trad_cache, this_id);
}
/* Implement the prev_register function for the SDE frame unwinder. */
static struct value *
mips_sde_frame_prev_register (const frame_info_ptr &this_frame,
void **this_cache,
int prev_regnum)
{
struct trad_frame_cache *trad_cache
= mips_sde_frame_cache (this_frame, this_cache);
return trad_frame_get_register (trad_cache, this_frame, prev_regnum);
}
/* Implement the sniffer function for the SDE frame unwinder. */
static int
mips_sde_frame_sniffer (const struct frame_unwind *self,
const frame_info_ptr &this_frame,
void **this_cache)
{
CORE_ADDR pc = get_frame_pc (this_frame);
const char *name;
find_pc_partial_function (pc, &name, NULL, NULL);
return (name
&& (strcmp (name, "_xcptcall") == 0
|| strcmp (name, "_sigtramp") == 0));
}
/* Data structure for the SDE frame unwinder. */
static const struct frame_unwind mips_sde_frame_unwind =
{
"mips sde sigtramp",
SIGTRAMP_FRAME,
default_frame_unwind_stop_reason,
mips_sde_frame_this_id,
mips_sde_frame_prev_register,
NULL,
mips_sde_frame_sniffer
};
/* Implement the this_base, this_locals, and this_args hooks
for the normal unwinder. */
static CORE_ADDR
mips_sde_frame_base_address (const frame_info_ptr &this_frame, void **this_cache)
{
struct trad_frame_cache *this_trad_cache
= mips_sde_frame_cache (this_frame, this_cache);
return trad_frame_get_this_base (this_trad_cache);
}
static const struct frame_base mips_sde_frame_base =
{
&mips_sde_frame_unwind,
mips_sde_frame_base_address,
mips_sde_frame_base_address,
mips_sde_frame_base_address
};
static const struct frame_base *
mips_sde_frame_base_sniffer (const frame_info_ptr &this_frame)
{
if (mips_sde_frame_sniffer (&mips_sde_frame_unwind, this_frame, NULL))
return &mips_sde_frame_base;
else
return NULL;
}
static void
mips_sde_elf_osabi_sniff_abi_tag_sections (bfd *abfd, asection *sect,
void *obj)
{
enum gdb_osabi *os_ident_ptr = (enum gdb_osabi *) obj;
const char *name;
name = bfd_section_name (sect);
/* The presence of a section with a ".sde" prefix is indicative
of an SDE binary. */
if (startswith (name, ".sde"))
*os_ident_ptr = GDB_OSABI_SDE;
}
/* OSABI sniffer for MIPS SDE. */
static enum gdb_osabi
mips_sde_elf_osabi_sniffer (bfd *abfd)
{
enum gdb_osabi osabi = GDB_OSABI_UNKNOWN;
unsigned int elfosabi;
/* If the generic sniffer gets a hit, return and let other sniffers
get a crack at it. */
for (asection *sect : gdb_bfd_sections (abfd))
generic_elf_osabi_sniff_abi_tag_sections (abfd, sect, &osabi);
if (osabi != GDB_OSABI_UNKNOWN)
return GDB_OSABI_UNKNOWN;
elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI];
if (elfosabi == ELFOSABI_NONE)
{
/* When elfosabi is ELFOSABI_NONE (0), then the ELF structures in the
file are conforming to the base specification for that machine
(there are no OS-specific extensions). In order to determine the
real OS in use we must look for OS notes that have been added.
For SDE, we simply look for sections named with .sde as prefixes. */
bfd_map_over_sections (abfd,
mips_sde_elf_osabi_sniff_abi_tag_sections,
&osabi);
}
return osabi;
}
static void
mips_sde_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
frame_unwind_append_unwinder (gdbarch, &mips_sde_frame_unwind);
frame_base_append_sniffer (gdbarch, mips_sde_frame_base_sniffer);
}
void _initialize_mips_sde_tdep ();
void
_initialize_mips_sde_tdep ()
{
gdbarch_register_osabi_sniffer (bfd_arch_mips,
bfd_target_elf_flavour,
mips_sde_elf_osabi_sniffer);
gdbarch_register_osabi (bfd_arch_mips, 0, GDB_OSABI_SDE, mips_sde_init_abi);
}