1 /* Native-dependent code for modern i386 BSD's.
3 Copyright (C) 2000-2014 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "gdb_assert.h"
26 #include <sys/types.h>
27 #include <sys/ptrace.h>
28 #include <machine/reg.h>
29 #include <machine/frame.h>
31 #include "i386-tdep.h"
32 #include "i387-tdep.h"
33 #include "i386bsd-nat.h"
34 #include "inf-ptrace.h"
37 /* In older BSD versions we cannot get at some of the segment
38 registers. FreeBSD for example didn't support the %fs and %gs
39 registers until the 3.0 release. We have autoconf checks for their
40 presence, and deal gracefully with their absence. */
42 /* Offset in `struct reg' where MEMBER is stored. */
43 #define REG_OFFSET(member) offsetof (struct reg, member)
45 /* At i386bsd_reg_offset[REGNUM] you'll find the offset in `struct
46 reg' where the GDB register REGNUM is stored. Unsupported
47 registers are marked with `-1'. */
48 static int i386bsd_r_reg_offset
[] =
59 REG_OFFSET (r_eflags
),
64 #ifdef HAVE_STRUCT_REG_R_FS
69 #ifdef HAVE_STRUCT_REG_R_GS
76 /* Macro to determine if a register is fetched with PT_GETREGS. */
77 #define GETREGS_SUPPLIES(regnum) \
78 ((0 <= (regnum) && (regnum) <= 15))
80 #ifdef HAVE_PT_GETXMMREGS
81 /* Set to 1 if the kernel supports PT_GETXMMREGS. Initialized to -1
82 so that we try PT_GETXMMREGS the first time around. */
83 static int have_ptrace_xmmregs
= -1;
87 /* Supply the general-purpose registers in GREGS, to REGCACHE. */
90 i386bsd_supply_gregset (struct regcache
*regcache
, const void *gregs
)
92 const char *regs
= gregs
;
95 for (regnum
= 0; regnum
< ARRAY_SIZE (i386bsd_r_reg_offset
); regnum
++)
97 int offset
= i386bsd_r_reg_offset
[regnum
];
100 regcache_raw_supply (regcache
, regnum
, regs
+ offset
);
104 /* Collect register REGNUM from REGCACHE and store its contents in
105 GREGS. If REGNUM is -1, collect and store all appropriate
109 i386bsd_collect_gregset (const struct regcache
*regcache
,
110 void *gregs
, int regnum
)
115 for (i
= 0; i
< ARRAY_SIZE (i386bsd_r_reg_offset
); i
++)
117 if (regnum
== -1 || regnum
== i
)
119 int offset
= i386bsd_r_reg_offset
[i
];
122 regcache_raw_collect (regcache
, i
, regs
+ offset
);
127 /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
128 for all registers (including the floating point registers). */
131 i386bsd_fetch_inferior_registers (struct target_ops
*ops
,
132 struct regcache
*regcache
, int regnum
)
134 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
138 if (ptrace (PT_GETREGS
, ptid_get_pid (inferior_ptid
),
139 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
140 perror_with_name (_("Couldn't get registers"));
142 i386bsd_supply_gregset (regcache
, ®s
);
147 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
150 #ifdef HAVE_PT_GETXMMREGS
153 if (have_ptrace_xmmregs
!= 0
154 && ptrace(PT_GETXMMREGS
, ptid_get_pid (inferior_ptid
),
155 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
157 have_ptrace_xmmregs
= 1;
158 i387_supply_fxsave (regcache
, -1, xmmregs
);
162 if (ptrace (PT_GETFPREGS
, ptid_get_pid (inferior_ptid
),
163 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
164 perror_with_name (_("Couldn't get floating point status"));
166 i387_supply_fsave (regcache
, -1, &fpregs
);
169 if (ptrace (PT_GETFPREGS
, ptid_get_pid (inferior_ptid
),
170 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
171 perror_with_name (_("Couldn't get floating point status"));
173 i387_supply_fsave (regcache
, -1, &fpregs
);
178 /* Store register REGNUM back into the inferior. If REGNUM is -1, do
179 this for all registers (including the floating point registers). */
182 i386bsd_store_inferior_registers (struct target_ops
*ops
,
183 struct regcache
*regcache
, int regnum
)
185 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
189 if (ptrace (PT_GETREGS
, ptid_get_pid (inferior_ptid
),
190 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
191 perror_with_name (_("Couldn't get registers"));
193 i386bsd_collect_gregset (regcache
, ®s
, regnum
);
195 if (ptrace (PT_SETREGS
, ptid_get_pid (inferior_ptid
),
196 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
197 perror_with_name (_("Couldn't write registers"));
203 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
206 #ifdef HAVE_PT_GETXMMREGS
209 if (have_ptrace_xmmregs
!= 0
210 && ptrace(PT_GETXMMREGS
, ptid_get_pid (inferior_ptid
),
211 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
213 have_ptrace_xmmregs
= 1;
215 i387_collect_fxsave (regcache
, regnum
, xmmregs
);
217 if (ptrace (PT_SETXMMREGS
, ptid_get_pid (inferior_ptid
),
218 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == -1)
219 perror_with_name (_("Couldn't write XMM registers"));
223 have_ptrace_xmmregs
= 0;
225 if (ptrace (PT_GETFPREGS
, ptid_get_pid (inferior_ptid
),
226 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
227 perror_with_name (_("Couldn't get floating point status"));
229 i387_collect_fsave (regcache
, regnum
, &fpregs
);
231 if (ptrace (PT_SETFPREGS
, ptid_get_pid (inferior_ptid
),
232 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
233 perror_with_name (_("Couldn't write floating point status"));
234 #ifdef HAVE_PT_GETXMMREGS
240 /* Create a prototype *BSD/i386 target. The client can override it
241 with local methods. */
244 i386bsd_target (void)
246 struct target_ops
*t
;
248 t
= inf_ptrace_target ();
249 t
->to_fetch_registers
= i386bsd_fetch_inferior_registers
;
250 t
->to_store_registers
= i386bsd_store_inferior_registers
;
255 /* Support for debug registers. */
257 #ifdef HAVE_PT_GETDBREGS
259 /* Not all versions of FreeBSD/i386 that support the debug registers
262 #define DBREG_DRX(d, x) ((&d->dr0)[x])
266 i386bsd_dr_get (ptid_t ptid
, int regnum
)
270 if (ptrace (PT_GETDBREGS
, ptid_get_pid (inferior_ptid
),
271 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
272 perror_with_name (_("Couldn't read debug registers"));
274 return DBREG_DRX ((&dbregs
), regnum
);
278 i386bsd_dr_set (int regnum
, unsigned int value
)
282 if (ptrace (PT_GETDBREGS
, ptid_get_pid (inferior_ptid
),
283 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
284 perror_with_name (_("Couldn't get debug registers"));
286 /* For some mysterious reason, some of the reserved bits in the
287 debug control register get set. Mask these off, otherwise the
288 ptrace call below will fail. */
289 DBREG_DRX ((&dbregs
), 7) &= ~(0x0000fc00);
291 DBREG_DRX ((&dbregs
), regnum
) = value
;
293 if (ptrace (PT_SETDBREGS
, ptid_get_pid (inferior_ptid
),
294 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
295 perror_with_name (_("Couldn't write debug registers"));
299 i386bsd_dr_set_control (unsigned long control
)
301 i386bsd_dr_set (7, control
);
305 i386bsd_dr_set_addr (int regnum
, CORE_ADDR addr
)
307 gdb_assert (regnum
>= 0 && regnum
<= 4);
309 i386bsd_dr_set (regnum
, addr
);
313 i386bsd_dr_get_addr (int regnum
)
315 return i386bsd_dr_get (inferior_ptid
, regnum
);
319 i386bsd_dr_get_status (void)
321 return i386bsd_dr_get (inferior_ptid
, 6);
325 i386bsd_dr_get_control (void)
327 return i386bsd_dr_get (inferior_ptid
, 7);
330 #endif /* PT_GETDBREGS */
333 /* Provide a prototype to silence -Wmissing-prototypes. */
334 void _initialize_i386bsd_nat (void);
337 _initialize_i386bsd_nat (void)
341 /* To support the recognition of signal handlers, i386bsd-tdep.c
342 hardcodes some constants. Inclusion of this file means that we
343 are compiling a native debugger, which means that we can use the
344 system header files and sysctl(3) to get at the relevant
347 #if defined (__FreeBSD_version) && __FreeBSD_version >= 400011
348 #define SC_REG_OFFSET i386fbsd4_sc_reg_offset
349 #elif defined (__FreeBSD_version) && __FreeBSD_version >= 300005
350 #define SC_REG_OFFSET i386fbsd_sc_reg_offset
351 #elif defined (NetBSD) || defined (__NetBSD_Version__)
352 #define SC_REG_OFFSET i386nbsd_sc_reg_offset
353 #elif defined (OpenBSD)
354 #define SC_REG_OFFSET i386obsd_sc_reg_offset
359 /* We only check the program counter, stack pointer and frame
360 pointer since these members of `struct sigcontext' are essential
361 for providing backtraces. More checks could be added, but would
362 involve adding configure checks for the appropriate structure
363 members, since older BSD's don't provide all of them. */
365 #define SC_PC_OFFSET SC_REG_OFFSET[I386_EIP_REGNUM]
366 #define SC_SP_OFFSET SC_REG_OFFSET[I386_ESP_REGNUM]
367 #define SC_FP_OFFSET SC_REG_OFFSET[I386_EBP_REGNUM]
369 /* Override the default value for the offset of the program counter
370 in the sigcontext structure. */
371 offset
= offsetof (struct sigcontext
, sc_pc
);
373 if (SC_PC_OFFSET
!= offset
)
376 offsetof (struct sigcontext, sc_pc) yields %d instead of %d.\n\
377 Please report this to <bug-gdb@gnu.org>."),
378 offset
, SC_PC_OFFSET
);
381 SC_PC_OFFSET
= offset
;
383 /* Likewise for the stack pointer. */
384 offset
= offsetof (struct sigcontext
, sc_sp
);
386 if (SC_SP_OFFSET
!= offset
)
389 offsetof (struct sigcontext, sc_sp) yields %d instead of %d.\n\
390 Please report this to <bug-gdb@gnu.org>."),
391 offset
, SC_SP_OFFSET
);
394 SC_SP_OFFSET
= offset
;
396 /* And the frame pointer. */
397 offset
= offsetof (struct sigcontext
, sc_fp
);
399 if (SC_FP_OFFSET
!= offset
)
402 offsetof (struct sigcontext, sc_fp) yields %d instead of %d.\n\
403 Please report this to <bug-gdb@gnu.org>."),
404 offset
, SC_FP_OFFSET
);
407 SC_FP_OFFSET
= offset
;
409 #endif /* SC_REG_OFFSET */