blob: d791bdab5a6fa04155b1e6fe0497b3151230ddd8 [file] [log] [blame]
/* Ravenscar x86-64 target support.
Copyright (C) 2020-2021 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 "gdbarch.h"
#include "gdbcore.h"
#include "regcache.h"
#include "amd64-tdep.h"
#include "inferior.h"
#include "ravenscar-thread.h"
#include "amd64-ravenscar-thread.h"
struct amd64_ravenscar_ops : public ravenscar_arch_ops
{
void fetch_registers (struct regcache *regcache, int regnum) override;
void store_registers (struct regcache *regcache, int regnum) override;
private:
/* Return the offset of the register in the context buffer. */
int register_offset (struct gdbarch *arch, int regnum);
};
/* x86-64 Ravenscar stores registers as:
type Context_Buffer is record
RIP : System.Address;
RFLAGS : EFLAGS;
RSP : System.Address;
RBX : System.Address;
RBP : System.Address;
R12 : System.Address;
R13 : System.Address;
R14 : System.Address;
R15 : System.Address;
end record;
*/
static const int register_layout[] =
{
AMD64_RIP_REGNUM,
AMD64_EFLAGS_REGNUM,
AMD64_RSP_REGNUM,
AMD64_RBX_REGNUM,
AMD64_RBP_REGNUM,
AMD64_R12_REGNUM,
AMD64_R13_REGNUM,
AMD64_R14_REGNUM,
AMD64_R15_REGNUM,
};
int
amd64_ravenscar_ops::register_offset (struct gdbarch *arch, int regnum)
{
for (int i = 0; i < ARRAY_SIZE (register_layout); ++i)
if (register_layout[i] == regnum)
return i * 8;
/* Not saved. */
return -1;
}
/* Supply register REGNUM, which has been saved at REGISTER_ADDR, to
the regcache. */
static void
supply_register_at_address (struct regcache *regcache, int regnum,
CORE_ADDR register_addr)
{
struct gdbarch *gdbarch = regcache->arch ();
int buf_size = register_size (gdbarch, regnum);
gdb_byte *buf;
buf = (gdb_byte *) alloca (buf_size);
read_memory (register_addr, buf, buf_size);
regcache->raw_supply (regnum, buf);
}
void
amd64_ravenscar_ops::fetch_registers (struct regcache *regcache, int regnum)
{
struct gdbarch *gdbarch = regcache->arch ();
const int num_regs = gdbarch_num_regs (gdbarch);
int current_regnum;
CORE_ADDR current_address;
CORE_ADDR thread_descriptor_address;
/* The tid is the thread_id field, which is a pointer to the thread. */
thread_descriptor_address = (CORE_ADDR) inferior_ptid.tid ();
/* Read registers. */
for (current_regnum = 0; current_regnum < num_regs; current_regnum++)
{
int offset = register_offset (gdbarch, current_regnum);
if (offset != -1)
{
current_address = thread_descriptor_address + offset;
supply_register_at_address (regcache, current_regnum,
current_address);
}
}
}
void
amd64_ravenscar_ops::store_registers (struct regcache *regcache, int regnum)
{
struct gdbarch *gdbarch = regcache->arch ();
int buf_size = register_size (gdbarch, regnum);
gdb_byte buf[buf_size];
CORE_ADDR register_address;
int offset = register_offset (gdbarch, regnum);
if (offset != -1)
{
register_address = inferior_ptid.tid () + offset;
regcache->raw_collect (regnum, buf);
write_memory (register_address,
buf,
buf_size);
}
}
/* The ravenscar_arch_ops vector for AMD64 targets. */
static struct amd64_ravenscar_ops amd64_ravenscar_ops;
/* Register amd64_ravenscar_ops in GDBARCH. */
void
register_amd64_ravenscar_ops (struct gdbarch *gdbarch)
{
set_gdbarch_ravenscar_ops (gdbarch, &amd64_ravenscar_ops);
}