Google Git Google Git
Sign in
gnu/binutils-gdb/users/ahayward/xml4/./gdb/i386-darwin-nat.c
blob: 023643fa56f98a26ba6a987a7616028a4d59a98c [file]
/* Darwin support for GDB, the GNU debugger.
Copyright (C) 1997-2018 Free Software Foundation, Inc.
Contributed by Apple Computer, 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 "frame.h"
#include "inferior.h"
#include "target.h"
#include "symfile.h"
#include "symtab.h"
#include "objfiles.h"
#include "gdbcmd.h"
#include "regcache.h"
#include "i386-tdep.h"
#include "i387-tdep.h"
#include "gdbarch.h"
#include "arch-utils.h"
#include "gdbcore.h"
#include "x86-nat.h"
#include "darwin-nat.h"
#include "i386-darwin-tdep.h"
#ifdef BFD64
#include "amd64-nat.h"
#include "amd64-tdep.h"
#include "amd64-darwin-tdep.h"
#endif
/* Read register values from the inferior process.
If REGNO is -1, do this for all registers.
Otherwise, REGNO specifies which register (so we can save time). */
static void
i386_darwin_fetch_inferior_registers (struct target_ops *ops,
struct regcache *regcache, int regno)
{
thread_t current_thread = ptid_get_tid (regcache_get_ptid (regcache));
int fetched = 0;
struct gdbarch *gdbarch = regcache->arch ();
#ifdef BFD64
if (gdbarch_ptr_bit (gdbarch) == 64)
{
if (regno == -1 || amd64_native_gregset_supplies_p (gdbarch, regno))
{
x86_thread_state_t gp_regs;
unsigned int gp_count = x86_THREAD_STATE_COUNT;
kern_return_t ret;
ret = thread_get_state
(current_thread, x86_THREAD_STATE, (thread_state_t) & gp_regs,
&gp_count);
if (ret != KERN_SUCCESS)
{
printf_unfiltered (_("Error calling thread_get_state for "
"GP registers for thread 0x%lx\n"),
(unsigned long) current_thread);
MACH_CHECK_ERROR (ret);
}
/* Some kernels don't sanitize the values. */
gp_regs.uts.ts64.__fs &= 0xffff;
gp_regs.uts.ts64.__gs &= 0xffff;
amd64_supply_native_gregset (regcache, &gp_regs.uts, -1);
fetched++;
}
if (regno == -1 || !amd64_native_gregset_supplies_p (gdbarch, regno))
{
x86_float_state_t fp_regs;
unsigned int fp_count = x86_FLOAT_STATE_COUNT;
kern_return_t ret;
ret = thread_get_state
(current_thread, x86_FLOAT_STATE, (thread_state_t) & fp_regs,
&fp_count);
if (ret != KERN_SUCCESS)
{
printf_unfiltered (_("Error calling thread_get_state for "
"float registers for thread 0x%lx\n"),
(unsigned long) current_thread);
MACH_CHECK_ERROR (ret);
}
amd64_supply_fxsave (regcache, -1, &fp_regs.ufs.fs64.__fpu_fcw);
fetched++;
}
}
else
#endif
{
if (regno == -1 || regno < I386_NUM_GREGS)
{
x86_thread_state32_t gp_regs;
unsigned int gp_count = x86_THREAD_STATE32_COUNT;
kern_return_t ret;
int i;
ret = thread_get_state
(current_thread, x86_THREAD_STATE32, (thread_state_t) &gp_regs,
&gp_count);
if (ret != KERN_SUCCESS)
{
printf_unfiltered (_("Error calling thread_get_state for "
"GP registers for thread 0x%lx\n"),
(unsigned long) current_thread);
MACH_CHECK_ERROR (ret);
}
for (i = 0; i < I386_NUM_GREGS; i++)
regcache_raw_supply
(regcache, i,
(char *)&gp_regs + i386_darwin_thread_state_reg_offset[i]);
fetched++;
}
if (regno == -1
|| (regno >= I386_ST0_REGNUM && regno < I386_SSE_NUM_REGS))
{
x86_float_state32_t fp_regs;
unsigned int fp_count = x86_FLOAT_STATE32_COUNT;
kern_return_t ret;
ret = thread_get_state
(current_thread, x86_FLOAT_STATE32, (thread_state_t) &fp_regs,
&fp_count);
if (ret != KERN_SUCCESS)
{
printf_unfiltered (_("Error calling thread_get_state for "
"float registers for thread 0x%lx\n"),
(unsigned long) current_thread);
MACH_CHECK_ERROR (ret);
}
i387_supply_fxsave (regcache, -1, &fp_regs.__fpu_fcw);
fetched++;
}
}
if (! fetched)
{
warning (_("unknown register %d"), regno);
regcache_raw_supply (regcache, regno, NULL);
}
}
/* Store our register values back into the inferior.
If REGNO is -1, do this for all registers.
Otherwise, REGNO specifies which register (so we can save time). */
static void
i386_darwin_store_inferior_registers (struct target_ops *ops,
struct regcache *regcache, int regno)
{
thread_t current_thread = ptid_get_tid (regcache_get_ptid (regcache));
struct gdbarch *gdbarch = regcache->arch ();
#ifdef BFD64
if (gdbarch_ptr_bit (gdbarch) == 64)
{
if (regno == -1 || amd64_native_gregset_supplies_p (gdbarch, regno))
{
x86_thread_state_t gp_regs;
kern_return_t ret;
unsigned int gp_count = x86_THREAD_STATE_COUNT;
ret = thread_get_state
(current_thread, x86_THREAD_STATE, (thread_state_t) &gp_regs,
&gp_count);
MACH_CHECK_ERROR (ret);
gdb_assert (gp_regs.tsh.flavor == x86_THREAD_STATE64);
gdb_assert (gp_regs.tsh.count == x86_THREAD_STATE64_COUNT);
amd64_collect_native_gregset (regcache, &gp_regs.uts, regno);
/* Some kernels don't sanitize the values. */
gp_regs.uts.ts64.__fs &= 0xffff;
gp_regs.uts.ts64.__gs &= 0xffff;
ret = thread_set_state (current_thread, x86_THREAD_STATE,
(thread_state_t) &gp_regs,
x86_THREAD_STATE_COUNT);
MACH_CHECK_ERROR (ret);
}
if (regno == -1 || !amd64_native_gregset_supplies_p (gdbarch, regno))
{
x86_float_state_t fp_regs;
kern_return_t ret;
unsigned int fp_count = x86_FLOAT_STATE_COUNT;
ret = thread_get_state
(current_thread, x86_FLOAT_STATE, (thread_state_t) & fp_regs,
&fp_count);
MACH_CHECK_ERROR (ret);
gdb_assert (fp_regs.fsh.flavor == x86_FLOAT_STATE64);
gdb_assert (fp_regs.fsh.count == x86_FLOAT_STATE64_COUNT);
amd64_collect_fxsave (regcache, regno, &fp_regs.ufs.fs64.__fpu_fcw);
ret = thread_set_state (current_thread, x86_FLOAT_STATE,
(thread_state_t) & fp_regs,
x86_FLOAT_STATE_COUNT);
MACH_CHECK_ERROR (ret);
}
}
else
#endif
{
if (regno == -1 || regno < I386_NUM_GREGS)
{
x86_thread_state32_t gp_regs;
kern_return_t ret;
unsigned int gp_count = x86_THREAD_STATE32_COUNT;
int i;
ret = thread_get_state
(current_thread, x86_THREAD_STATE32, (thread_state_t) &gp_regs,
&gp_count);
MACH_CHECK_ERROR (ret);
for (i = 0; i < I386_NUM_GREGS; i++)
if (regno == -1 || regno == i)
regcache_raw_collect
(regcache, i,
(char *)&gp_regs + i386_darwin_thread_state_reg_offset[i]);
ret = thread_set_state (current_thread, x86_THREAD_STATE32,
(thread_state_t) &gp_regs,
x86_THREAD_STATE32_COUNT);
MACH_CHECK_ERROR (ret);
}
if (regno == -1
|| (regno >= I386_ST0_REGNUM && regno < I386_SSE_NUM_REGS))
{
x86_float_state32_t fp_regs;
unsigned int fp_count = x86_FLOAT_STATE32_COUNT;
kern_return_t ret;
ret = thread_get_state
(current_thread, x86_FLOAT_STATE32, (thread_state_t) & fp_regs,
&fp_count);
MACH_CHECK_ERROR (ret);
i387_collect_fxsave (regcache, regno, &fp_regs.__fpu_fcw);
ret = thread_set_state (current_thread, x86_FLOAT_STATE32,
(thread_state_t) &fp_regs,
x86_FLOAT_STATE32_COUNT);
MACH_CHECK_ERROR (ret);
}
}
}
/* Support for debug registers, boosted mostly from i386-linux-nat.c. */
static void
i386_darwin_dr_set (int regnum, CORE_ADDR value)
{
int current_pid;
thread_t current_thread;
x86_debug_state_t dr_regs;
kern_return_t ret;
unsigned int dr_count;
gdb_assert (regnum >= 0 && regnum <= DR_CONTROL);
current_thread = ptid_get_tid (inferior_ptid);
dr_regs.dsh.flavor = x86_DEBUG_STATE;
dr_regs.dsh.count = x86_DEBUG_STATE_COUNT;
dr_count = x86_DEBUG_STATE_COUNT;
ret = thread_get_state (current_thread, x86_DEBUG_STATE,
(thread_state_t) &dr_regs, &dr_count);
MACH_CHECK_ERROR (ret);
switch (dr_regs.dsh.flavor)
{
case x86_DEBUG_STATE32:
switch (regnum)
{
case 0:
dr_regs.uds.ds32.__dr0 = value;
break;
case 1:
dr_regs.uds.ds32.__dr1 = value;
break;
case 2:
dr_regs.uds.ds32.__dr2 = value;
break;
case 3:
dr_regs.uds.ds32.__dr3 = value;
break;
case 4:
dr_regs.uds.ds32.__dr4 = value;
break;
case 5:
dr_regs.uds.ds32.__dr5 = value;
break;
case 6:
dr_regs.uds.ds32.__dr6 = value;
break;
case 7:
dr_regs.uds.ds32.__dr7 = value;
break;
}
break;
#ifdef BFD64
case x86_DEBUG_STATE64:
switch (regnum)
{
case 0:
dr_regs.uds.ds64.__dr0 = value;
break;
case 1:
dr_regs.uds.ds64.__dr1 = value;
break;
case 2:
dr_regs.uds.ds64.__dr2 = value;
break;
case 3:
dr_regs.uds.ds64.__dr3 = value;
break;
case 4:
dr_regs.uds.ds64.__dr4 = value;
break;
case 5:
dr_regs.uds.ds64.__dr5 = value;
break;
case 6:
dr_regs.uds.ds64.__dr6 = value;
break;
case 7:
dr_regs.uds.ds64.__dr7 = value;
break;
}
break;
#endif
}
ret = thread_set_state (current_thread, dr_regs.dsh.flavor,
(thread_state_t) &dr_regs.uds, dr_count);
MACH_CHECK_ERROR (ret);
}
static CORE_ADDR
i386_darwin_dr_get (int regnum)
{
thread_t current_thread;
x86_debug_state_t dr_regs;
kern_return_t ret;
unsigned int dr_count;
gdb_assert (regnum >= 0 && regnum <= DR_CONTROL);
current_thread = ptid_get_tid (inferior_ptid);
dr_regs.dsh.flavor = x86_DEBUG_STATE;
dr_regs.dsh.count = x86_DEBUG_STATE_COUNT;
dr_count = x86_DEBUG_STATE_COUNT;
ret = thread_get_state (current_thread, x86_DEBUG_STATE,
(thread_state_t) &dr_regs, &dr_count);
MACH_CHECK_ERROR (ret);
switch (dr_regs.dsh.flavor)
{
case x86_DEBUG_STATE32:
switch (regnum)
{
case 0:
return dr_regs.uds.ds32.__dr0;
case 1:
return dr_regs.uds.ds32.__dr1;
case 2:
return dr_regs.uds.ds32.__dr2;
case 3:
return dr_regs.uds.ds32.__dr3;
case 4:
return dr_regs.uds.ds32.__dr4;
case 5:
return dr_regs.uds.ds32.__dr5;
case 6:
return dr_regs.uds.ds32.__dr6;
case 7:
return dr_regs.uds.ds32.__dr7;
default:
return -1;
}
break;
#ifdef BFD64
case x86_DEBUG_STATE64:
switch (regnum)
{
case 0:
return dr_regs.uds.ds64.__dr0;
case 1:
return dr_regs.uds.ds64.__dr1;
case 2:
return dr_regs.uds.ds64.__dr2;
case 3:
return dr_regs.uds.ds64.__dr3;
case 4:
return dr_regs.uds.ds64.__dr4;
case 5:
return dr_regs.uds.ds64.__dr5;
case 6:
return dr_regs.uds.ds64.__dr6;
case 7:
return dr_regs.uds.ds64.__dr7;
default:
return -1;
}
break;
#endif
default:
return -1;
}
}
static void
i386_darwin_dr_set_control (unsigned long control)
{
i386_darwin_dr_set (DR_CONTROL, control);
}
static void
i386_darwin_dr_set_addr (int regnum, CORE_ADDR addr)
{
gdb_assert (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR);
i386_darwin_dr_set (DR_FIRSTADDR + regnum, addr);
}
static CORE_ADDR
i386_darwin_dr_get_addr (int regnum)
{
return i386_darwin_dr_get (regnum);
}
static unsigned long
i386_darwin_dr_get_status (void)
{
return i386_darwin_dr_get (DR_STATUS);
}
static unsigned long
i386_darwin_dr_get_control (void)
{
return i386_darwin_dr_get (DR_CONTROL);
}
void
darwin_check_osabi (darwin_inferior *inf, thread_t thread)
{
if (gdbarch_osabi (target_gdbarch ()) == GDB_OSABI_UNKNOWN)
{
/* Attaching to a process. Let's figure out what kind it is. */
x86_thread_state_t gp_regs;
struct gdbarch_info info;
unsigned int gp_count = x86_THREAD_STATE_COUNT;
kern_return_t ret;
ret = thread_get_state (thread, x86_THREAD_STATE,
(thread_state_t) &gp_regs, &gp_count);
if (ret != KERN_SUCCESS)
{
MACH_CHECK_ERROR (ret);
return;
}
gdbarch_info_init (&info);
gdbarch_info_fill (&info);
info.byte_order = gdbarch_byte_order (target_gdbarch ());
info.osabi = GDB_OSABI_DARWIN;
if (gp_regs.tsh.flavor == x86_THREAD_STATE64)
info.bfd_arch_info = bfd_lookup_arch (bfd_arch_i386,
bfd_mach_x86_64);
else
info.bfd_arch_info = bfd_lookup_arch (bfd_arch_i386,
bfd_mach_i386_i386);
gdbarch_update_p (info);
}
}
#define X86_EFLAGS_T 0x100UL
/* Returning from a signal trampoline is done by calling a
special system call (sigreturn). This system call
restores the registers that were saved when the signal was
raised, including %eflags/%rflags. That means that single-stepping
won't work. Instead, we'll have to modify the signal context
that's about to be restored, and set the trace flag there. */
static int
i386_darwin_sstep_at_sigreturn (x86_thread_state_t *regs)
{
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
static const gdb_byte darwin_syscall[] = { 0xcd, 0x80 }; /* int 0x80 */
gdb_byte buf[sizeof (darwin_syscall)];
/* Check if PC is at a sigreturn system call. */
if (target_read_memory (regs->uts.ts32.__eip, buf, sizeof (buf)) == 0
&& memcmp (buf, darwin_syscall, sizeof (darwin_syscall)) == 0
&& regs->uts.ts32.__eax == 0xb8 /* SYS_sigreturn */)
{
ULONGEST uctx_addr;
ULONGEST mctx_addr;
ULONGEST flags_addr;
unsigned int eflags;
uctx_addr = read_memory_unsigned_integer
(regs->uts.ts32.__esp + 4, 4, byte_order);
mctx_addr = read_memory_unsigned_integer
(uctx_addr + 28, 4, byte_order);
flags_addr = mctx_addr + 12 + 9 * 4;
read_memory (flags_addr, (gdb_byte *) &eflags, 4);
eflags |= X86_EFLAGS_T;
write_memory (flags_addr, (gdb_byte *) &eflags, 4);
return 1;
}
return 0;
}
#ifdef BFD64
static int
amd64_darwin_sstep_at_sigreturn (x86_thread_state_t *regs)
{
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
static const gdb_byte darwin_syscall[] = { 0x0f, 0x05 }; /* syscall */
gdb_byte buf[sizeof (darwin_syscall)];
/* Check if PC is at a sigreturn system call. */
if (target_read_memory (regs->uts.ts64.__rip, buf, sizeof (buf)) == 0
&& memcmp (buf, darwin_syscall, sizeof (darwin_syscall)) == 0
&& (regs->uts.ts64.__rax & 0xffffffff) == 0x20000b8 /* SYS_sigreturn */)
{
ULONGEST mctx_addr;
ULONGEST flags_addr;
unsigned int rflags;
mctx_addr = read_memory_unsigned_integer
(regs->uts.ts64.__rdi + 48, 8, byte_order);
flags_addr = mctx_addr + 16 + 17 * 8;
/* AMD64 is little endian. */
read_memory (flags_addr, (gdb_byte *) &rflags, 4);
rflags |= X86_EFLAGS_T;
write_memory (flags_addr, (gdb_byte *) &rflags, 4);
return 1;
}
return 0;
}
#endif
void
darwin_set_sstep (thread_t thread, int enable)
{
x86_thread_state_t regs;
unsigned int count = x86_THREAD_STATE_COUNT;
kern_return_t kret;
kret = thread_get_state (thread, x86_THREAD_STATE,
(thread_state_t) &regs, &count);
if (kret != KERN_SUCCESS)
{
printf_unfiltered (_("darwin_set_sstep: error %x, thread=%x\n"),
kret, thread);
return;
}
switch (regs.tsh.flavor)
{
case x86_THREAD_STATE32:
{
__uint32_t bit = enable ? X86_EFLAGS_T : 0;
if (enable && i386_darwin_sstep_at_sigreturn (&regs))
return;
if ((regs.uts.ts32.__eflags & X86_EFLAGS_T) == bit)
return;
regs.uts.ts32.__eflags
= (regs.uts.ts32.__eflags & ~X86_EFLAGS_T) | bit;
kret = thread_set_state (thread, x86_THREAD_STATE,
(thread_state_t) &regs, count);
MACH_CHECK_ERROR (kret);
}
break;
#ifdef BFD64
case x86_THREAD_STATE64:
{
__uint64_t bit = enable ? X86_EFLAGS_T : 0;
if (enable && amd64_darwin_sstep_at_sigreturn (&regs))
return;
if ((regs.uts.ts64.__rflags & X86_EFLAGS_T) == bit)
return;
regs.uts.ts64.__rflags
= (regs.uts.ts64.__rflags & ~X86_EFLAGS_T) | bit;
kret = thread_set_state (thread, x86_THREAD_STATE,
(thread_state_t) &regs, count);
MACH_CHECK_ERROR (kret);
}
break;
#endif
default:
error (_("darwin_set_sstep: unknown flavour: %d"), regs.tsh.flavor);
}
}
void
darwin_complete_target (struct target_ops *target)
{
#ifdef BFD64
amd64_native_gregset64_reg_offset = amd64_darwin_thread_state_reg_offset;
amd64_native_gregset64_num_regs = amd64_darwin_thread_state_num_regs;
amd64_native_gregset32_reg_offset = i386_darwin_thread_state_reg_offset;
amd64_native_gregset32_num_regs = i386_darwin_thread_state_num_regs;
#endif
x86_use_watchpoints (target);
x86_dr_low.set_control = i386_darwin_dr_set_control;
x86_dr_low.set_addr = i386_darwin_dr_set_addr;
x86_dr_low.get_addr = i386_darwin_dr_get_addr;
x86_dr_low.get_status = i386_darwin_dr_get_status;
x86_dr_low.get_control = i386_darwin_dr_get_control;
/* Let's assume that the kernel is 64 bits iff the executable is. */
#ifdef __x86_64__
x86_set_debug_register_length (8);
#else
x86_set_debug_register_length (4);
#endif
target->to_fetch_registers = i386_darwin_fetch_inferior_registers;
target->to_store_registers = i386_darwin_store_inferior_registers;
}