/* Low level interface to i386 running the GNU Hurd.
Copyright (C) 1992-2018 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/>. */
/* Mach/Hurd headers are not yet ready for C++ compilation. */
extern "C"
{
#include <mach.h>
#include <mach_error.h>
#include <mach/message.h>
#include <mach/exception.h>
}
#include "defs.h"
#include "x86-nat.h"
#include "inferior.h"
#include "floatformat.h"
#include "regcache.h"
#include "i386-tdep.h"
#include "gnu-nat.h"
#include "inf-child.h"
#include "i387-tdep.h"
/* Offset to the thread_state_t location where REG is stored. */
#define REG_OFFSET(reg) offsetof (struct i386_thread_state, reg)
/* At REG_OFFSET[N] is the offset to the thread_state_t location where
the GDB register N is stored. */
static int reg_offset[] =
{
REG_OFFSET (eax), REG_OFFSET (ecx), REG_OFFSET (edx), REG_OFFSET (ebx),
REG_OFFSET (uesp), REG_OFFSET (ebp), REG_OFFSET (esi), REG_OFFSET (edi),
REG_OFFSET (eip), REG_OFFSET (efl), REG_OFFSET (cs), REG_OFFSET (ss),
REG_OFFSET (ds), REG_OFFSET (es), REG_OFFSET (fs), REG_OFFSET (gs)
};
#define REG_ADDR(state, regnum) ((char *)(state) + reg_offset[regnum])
/* The i386 GNU Hurd target. */
#ifdef i386_DEBUG_STATE
using gnu_base_target = x86_nat_target<gnu_nat_target>;
#else
using gnu_base_target = gnu_nat_target;
#endif
struct i386_gnu_nat_target final : public gnu_base_target
{
void fetch_registers (struct regcache *, int) override;
void store_registers (struct regcache *, int) override;
};
static i386_gnu_nat_target the_i386_gnu_nat_target;
/* Get the whole floating-point state of THREAD and record the values
of the corresponding (pseudo) registers. */
static void
fetch_fpregs (struct regcache *regcache, struct proc *thread)
{
mach_msg_type_number_t count = i386_FLOAT_STATE_COUNT;
struct i386_float_state state;
kern_return_t err;
err = thread_get_state (thread->port, i386_FLOAT_STATE,
(thread_state_t) &state, &count);
if (err)
{
warning (_("Couldn't fetch floating-point state from %s"),
proc_string (thread));
return;
}
if (!state.initialized)
{
/* The floating-point state isn't initialized. */
i387_supply_fsave (regcache, -1, NULL);
}
else
{
/* Supply the floating-point registers. */
i387_supply_fsave (regcache, -1, state.hw_state);
}
}
/* Fetch register REGNO, or all regs if REGNO is -1. */
static void
gnu_fetch_registers (struct target_ops *ops,
struct regcache *regcache, int regno)
{
struct proc *thread;
ptid_t ptid = regcache->ptid ();
/* Make sure we know about new threads. */
inf_update_procs (gnu_current_inf);
thread = inf_tid_to_thread (gnu_current_inf, ptid.lwp ());
if (!thread)
error (_("Can't fetch registers from thread %s: No such thread"),
target_pid_to_str (ptid));
if (regno < I386_NUM_GREGS || regno == -1)
{
thread_state_t state;
/* This does the dirty work for us. */
state = proc_get_state (thread, 0);
if (!state)
{
warning (_("Couldn't fetch registers from %s"),
proc_string (thread));
return;
}
if (regno == -1)
{
int i;
proc_debug (thread, "fetching all register");
for (i = 0; i < I386_NUM_GREGS; i++)
regcache->raw_supply (i, REG_ADDR (state, i));
thread->fetched_regs = ~0;
}
else
{
proc_debug (thread, "fetching register %s",
gdbarch_register_name (regcache->arch (),
regno));
regcache->raw_supply (regno, REG_ADDR (state, regno));
thread->fetched_regs |= (1 << regno);
}
}
if (regno >= I386_NUM_GREGS || regno == -1)
{
proc_debug (thread, "fetching floating-point registers");
fetch_fpregs (regcache, thread);
}
}
/* Store the whole floating-point state into THREAD using information
from the corresponding (pseudo) registers. */
static void
store_fpregs (const struct regcache *regcache, struct proc *thread, int regno)
{
mach_msg_type_number_t count = i386_FLOAT_STATE_COUNT;
struct i386_float_state state;
kern_return_t err;
err = thread_get_state (thread->port, i386_FLOAT_STATE,
(thread_state_t) &state, &count);
if (err)
{
warning (_("Couldn't fetch floating-point state from %s"),
proc_string (thread));
return;
}
/* FIXME: kettenis/2001-07-15: Is this right? Should we somehow
take into account DEPRECATED_REGISTER_VALID like the old code did? */
i387_collect_fsave (regcache, regno, state.hw_state);
err = thread_set_state (thread->port, i386_FLOAT_STATE,
(thread_state_t) &state, i386_FLOAT_STATE_COUNT);
if (err)
{
warning (_("Couldn't store floating-point state into %s"),
proc_string (thread));
return;
}
}
/* Store at least register REGNO, or all regs if REGNO == -1. */
static void
gnu_store_registers (struct target_ops *ops,
struct regcache *regcache, int regno)
{
struct proc *thread;
struct gdbarch *gdbarch = regcache->arch ();
ptid_t ptid = regcache->ptid ();
/* Make sure we know about new threads. */
inf_update_procs (gnu_current_inf);
thread = inf_tid_to_thread (gnu_current_inf, ptid.lwp ());
if (!thread)
error (_("Couldn't store registers into thread %s: No such thread"),
target_pid_to_str (ptid));
if (regno < I386_NUM_GREGS || regno == -1)
{
thread_state_t state;
thread_state_data_t old_state;
int was_aborted = thread->aborted;
int was_valid = thread->state_valid;
int trace;
if (!was_aborted && was_valid)
memcpy (&old_state, &thread->state, sizeof (old_state));
state = proc_get_state (thread, 1);
if (!state)
{
warning (_("Couldn't store registers into %s"),
proc_string (thread));
return;
}
/* Save the T bit. We might try to restore the %eflags register
below, but changing the T bit would seriously confuse GDB. */
trace = ((struct i386_thread_state *)state)->efl & 0x100;
if (!was_aborted && was_valid)
/* See which registers have changed after aborting the thread. */
{
int check_regno;
for (check_regno = 0; check_regno < I386_NUM_GREGS; check_regno++)
if ((thread->fetched_regs & (1 << check_regno))
&& memcpy (REG_ADDR (&old_state, check_regno),
REG_ADDR (state, check_regno),
register_size (gdbarch, check_regno)))
/* Register CHECK_REGNO has changed! Ack! */
{
warning (_("Register %s changed after the thread was aborted"),
gdbarch_register_name (gdbarch, check_regno));
if (regno >= 0 && regno != check_regno)
/* Update GDB's copy of the register. */
regcache->raw_supply (check_regno,
REG_ADDR (state, check_regno));
else
warning (_("... also writing this register! "
"Suspicious..."));
}
}
if (regno == -1)
{
int i;
proc_debug (thread, "storing all registers");
for (i = 0; i < I386_NUM_GREGS; i++)
if (REG_VALID == regcache->get_register_status (i))
regcache->raw_collect (i, REG_ADDR (state, i));
}
else
{
proc_debug (thread, "storing register %s",
gdbarch_register_name (gdbarch, regno));
gdb_assert (REG_VALID == regcache->get_register_status (regno));
regcache->raw_collect (regno, REG_ADDR (state, regno));
}
/* Restore the T bit. */
((struct i386_thread_state *)state)->efl &= ~0x100;
((struct i386_thread_state *)state)->efl |= trace;
}
if (regno >= I386_NUM_GREGS || regno == -1)
{
proc_debug (thread, "storing floating-point registers");
store_fpregs (regcache, thread, regno);
}
}
/* Support for debug registers. */
#ifdef i386_DEBUG_STATE
/* Get debug registers for thread THREAD. */
static void
i386_gnu_dr_get (struct i386_debug_state *regs, struct proc *thread)
{
mach_msg_type_number_t count = i386_DEBUG_STATE_COUNT;
kern_return_t err;
err = thread_get_state (thread->port, i386_DEBUG_STATE,
(thread_state_t) regs, &count);
if (err != 0 || count != i386_DEBUG_STATE_COUNT)
warning (_("Couldn't fetch debug state from %s"),
proc_string (thread));
}
/* Set debug registers for thread THREAD. */
static void
i386_gnu_dr_set (const struct i386_debug_state *regs, struct proc *thread)
{
kern_return_t err;
err = thread_set_state (thread->port, i386_DEBUG_STATE,
(thread_state_t) regs, i386_DEBUG_STATE_COUNT);
if (err != 0)
warning (_("Couldn't store debug state into %s"),
proc_string (thread));
}
/* Set DR_CONTROL in THREAD. */
static void
i386_gnu_dr_set_control_one (struct proc *thread, void *arg)
{
unsigned long *control = (unsigned long *) arg;
struct i386_debug_state regs;
i386_gnu_dr_get (®s, thread);
regs.dr[DR_CONTROL] = *control;
i386_gnu_dr_set (®s, thread);
}
/* Set DR_CONTROL to CONTROL in all threads. */
static void
i386_gnu_dr_set_control (unsigned long control)
{
inf_update_procs (gnu_current_inf);
inf_threads (gnu_current_inf, i386_gnu_dr_set_control_one, &control);
}
/* Parameters to set a debugging address. */
struct reg_addr
{
int regnum; /* Register number (zero based). */
CORE_ADDR addr; /* Address. */
};
/* Set address REGNUM (zero based) to ADDR in THREAD. */
static void
i386_gnu_dr_set_addr_one (struct proc *thread, void *arg)
{
struct reg_addr *reg_addr = (struct reg_addr *) arg;
struct i386_debug_state regs;
i386_gnu_dr_get (®s, thread);
regs.dr[reg_addr->regnum] = reg_addr->addr;
i386_gnu_dr_set (®s, thread);
}
/* Set address REGNUM (zero based) to ADDR in all threads. */
static void
i386_gnu_dr_set_addr (int regnum, CORE_ADDR addr)
{
struct reg_addr reg_addr;
gdb_assert (DR_FIRSTADDR <= regnum && regnum <= DR_LASTADDR);
reg_addr.regnum = regnum;
reg_addr.addr = addr;
inf_update_procs (gnu_current_inf);
inf_threads (gnu_current_inf, i386_gnu_dr_set_addr_one, ®_addr);
}
/* Get debug register REGNUM value from only the one LWP of PTID. */
static unsigned long
i386_gnu_dr_get_reg (ptid_t ptid, int regnum)
{
struct i386_debug_state regs;
struct proc *thread;
/* Make sure we know about new threads. */
inf_update_procs (gnu_current_inf);
thread = inf_tid_to_thread (gnu_current_inf, ptid.lwp ());
i386_gnu_dr_get (®s, thread);
return regs.dr[regnum];
}
/* Return the inferior's debug register REGNUM. */
static CORE_ADDR
i386_gnu_dr_get_addr (int regnum)
{
gdb_assert (DR_FIRSTADDR <= regnum && regnum <= DR_LASTADDR);
return i386_gnu_dr_get_reg (inferior_ptid, regnum);
}
/* Get DR_STATUS from only the one thread of INFERIOR_PTID. */
static unsigned long
i386_gnu_dr_get_status (void)
{
return i386_gnu_dr_get_reg (inferior_ptid, DR_STATUS);
}
/* Return the inferior's DR7 debug control register. */
static unsigned long
i386_gnu_dr_get_control (void)
{
return i386_gnu_dr_get_reg (inferior_ptid, DR_CONTROL);
}
#endif /* i386_DEBUG_STATE */
void
_initialize_i386gnu_nat (void)
{
#ifdef i386_DEBUG_STATE
x86_dr_low.set_control = i386_gnu_dr_set_control;
gdb_assert (DR_FIRSTADDR == 0 && DR_LASTADDR < i386_DEBUG_STATE_COUNT);
x86_dr_low.set_addr = i386_gnu_dr_set_addr;
x86_dr_low.get_addr = i386_gnu_dr_get_addr;
x86_dr_low.get_status = i386_gnu_dr_get_status;
x86_dr_low.get_control = i386_gnu_dr_get_control;
x86_set_debug_register_length (4);
#endif /* i386_DEBUG_STATE */
/* Register the target. */
add_inf_child_target (&the_i386_gnu_nat_target);
}