1 /* Native-dependent code for modern i386 BSD's.
3 Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010,
4 2011 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
25 #include "gdb_assert.h"
28 #include <sys/types.h>
29 #include <sys/ptrace.h>
30 #include <machine/reg.h>
31 #include <machine/frame.h>
33 #include "i386-tdep.h"
34 #include "i387-tdep.h"
35 #include "i386bsd-nat.h"
36 #include "inf-ptrace.h"
39 /* In older BSD versions we cannot get at some of the segment
40 registers. FreeBSD for example didn't support the %fs and %gs
41 registers until the 3.0 release. We have autoconf checks for their
42 presence, and deal gracefully with their absence. */
44 /* Offset in `struct reg' where MEMBER is stored. */
45 #define REG_OFFSET(member) offsetof (struct reg, member)
47 /* At i386bsd_reg_offset[REGNUM] you'll find the offset in `struct
48 reg' where the GDB register REGNUM is stored. Unsupported
49 registers are marked with `-1'. */
50 static int i386bsd_r_reg_offset
[] =
61 REG_OFFSET (r_eflags
),
66 #ifdef HAVE_STRUCT_REG_R_FS
71 #ifdef HAVE_STRUCT_REG_R_GS
78 /* Macro to determine if a register is fetched with PT_GETREGS. */
79 #define GETREGS_SUPPLIES(regnum) \
80 ((0 <= (regnum) && (regnum) <= 15))
82 #ifdef HAVE_PT_GETXMMREGS
83 /* Set to 1 if the kernel supports PT_GETXMMREGS. Initialized to -1
84 so that we try PT_GETXMMREGS the first time around. */
85 static int have_ptrace_xmmregs
= -1;
89 /* Supply the general-purpose registers in GREGS, to REGCACHE. */
92 i386bsd_supply_gregset (struct regcache
*regcache
, const void *gregs
)
94 const char *regs
= gregs
;
97 for (regnum
= 0; regnum
< ARRAY_SIZE (i386bsd_r_reg_offset
); regnum
++)
99 int offset
= i386bsd_r_reg_offset
[regnum
];
102 regcache_raw_supply (regcache
, regnum
, regs
+ offset
);
106 /* Collect register REGNUM from REGCACHE and store its contents in
107 GREGS. If REGNUM is -1, collect and store all appropriate
111 i386bsd_collect_gregset (const struct regcache
*regcache
,
112 void *gregs
, int regnum
)
117 for (i
= 0; i
< ARRAY_SIZE (i386bsd_r_reg_offset
); i
++)
119 if (regnum
== -1 || regnum
== i
)
121 int offset
= i386bsd_r_reg_offset
[i
];
124 regcache_raw_collect (regcache
, i
, regs
+ offset
);
129 /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
130 for all registers (including the floating point registers). */
133 i386bsd_fetch_inferior_registers (struct target_ops
*ops
,
134 struct regcache
*regcache
, int regnum
)
136 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
140 if (ptrace (PT_GETREGS
, PIDGET (inferior_ptid
),
141 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
142 perror_with_name (_("Couldn't get registers"));
144 i386bsd_supply_gregset (regcache
, ®s
);
149 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
152 #ifdef HAVE_PT_GETXMMREGS
155 if (have_ptrace_xmmregs
!= 0
156 && ptrace(PT_GETXMMREGS
, PIDGET (inferior_ptid
),
157 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
159 have_ptrace_xmmregs
= 1;
160 i387_supply_fxsave (regcache
, -1, xmmregs
);
164 if (ptrace (PT_GETFPREGS
, PIDGET (inferior_ptid
),
165 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
166 perror_with_name (_("Couldn't get floating point status"));
168 i387_supply_fsave (regcache
, -1, &fpregs
);
171 if (ptrace (PT_GETFPREGS
, PIDGET (inferior_ptid
),
172 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
173 perror_with_name (_("Couldn't get floating point status"));
175 i387_supply_fsave (regcache
, -1, &fpregs
);
180 /* Store register REGNUM back into the inferior. If REGNUM is -1, do
181 this for all registers (including the floating point registers). */
184 i386bsd_store_inferior_registers (struct target_ops
*ops
,
185 struct regcache
*regcache
, int regnum
)
187 if (regnum
== -1 || GETREGS_SUPPLIES (regnum
))
191 if (ptrace (PT_GETREGS
, PIDGET (inferior_ptid
),
192 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
193 perror_with_name (_("Couldn't get registers"));
195 i386bsd_collect_gregset (regcache
, ®s
, regnum
);
197 if (ptrace (PT_SETREGS
, PIDGET (inferior_ptid
),
198 (PTRACE_TYPE_ARG3
) ®s
, 0) == -1)
199 perror_with_name (_("Couldn't write registers"));
205 if (regnum
== -1 || regnum
>= I386_ST0_REGNUM
)
208 #ifdef HAVE_PT_GETXMMREGS
211 if (have_ptrace_xmmregs
!= 0
212 && ptrace(PT_GETXMMREGS
, PIDGET (inferior_ptid
),
213 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == 0)
215 have_ptrace_xmmregs
= 1;
217 i387_collect_fxsave (regcache
, regnum
, xmmregs
);
219 if (ptrace (PT_SETXMMREGS
, PIDGET (inferior_ptid
),
220 (PTRACE_TYPE_ARG3
) xmmregs
, 0) == -1)
221 perror_with_name (_("Couldn't write XMM registers"));
225 have_ptrace_xmmregs
= 0;
227 if (ptrace (PT_GETFPREGS
, PIDGET (inferior_ptid
),
228 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
229 perror_with_name (_("Couldn't get floating point status"));
231 i387_collect_fsave (regcache
, regnum
, &fpregs
);
233 if (ptrace (PT_SETFPREGS
, PIDGET (inferior_ptid
),
234 (PTRACE_TYPE_ARG3
) &fpregs
, 0) == -1)
235 perror_with_name (_("Couldn't write floating point status"));
236 #ifdef HAVE_PT_GETXMMREGS
242 /* Create a prototype *BSD/i386 target. The client can override it
243 with local methods. */
246 i386bsd_target (void)
248 struct target_ops
*t
;
250 t
= inf_ptrace_target ();
251 t
->to_fetch_registers
= i386bsd_fetch_inferior_registers
;
252 t
->to_store_registers
= i386bsd_store_inferior_registers
;
257 /* Support for debug registers. */
259 #ifdef HAVE_PT_GETDBREGS
261 /* Not all versions of FreeBSD/i386 that support the debug registers
264 #define DBREG_DRX(d, x) ((&d->dr0)[x])
268 i386bsd_dr_get (ptid_t ptid
, int regnum
)
272 if (ptrace (PT_GETDBREGS
, PIDGET (inferior_ptid
),
273 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
274 perror_with_name (_("Couldn't read debug registers"));
276 return DBREG_DRX ((&dbregs
), regnum
);
280 i386bsd_dr_set (int regnum
, unsigned int value
)
284 if (ptrace (PT_GETDBREGS
, PIDGET (inferior_ptid
),
285 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
286 perror_with_name (_("Couldn't get debug registers"));
288 /* For some mysterious reason, some of the reserved bits in the
289 debug control register get set. Mask these off, otherwise the
290 ptrace call below will fail. */
291 DBREG_DRX ((&dbregs
), 7) &= ~(0x0000fc00);
293 DBREG_DRX ((&dbregs
), regnum
) = value
;
295 if (ptrace (PT_SETDBREGS
, PIDGET (inferior_ptid
),
296 (PTRACE_TYPE_ARG3
) &dbregs
, 0) == -1)
297 perror_with_name (_("Couldn't write debug registers"));
301 i386bsd_dr_set_control (unsigned long control
)
303 i386bsd_dr_set (7, control
);
307 i386bsd_dr_set_addr (int regnum
, CORE_ADDR addr
)
309 gdb_assert (regnum
>= 0 && regnum
<= 4);
311 i386bsd_dr_set (regnum
, addr
);
315 i386bsd_dr_get_addr (int regnum
)
317 return i386bsd_dr_get (inferior_ptid
, regnum
);
321 i386bsd_dr_get_status (void)
323 return i386bsd_dr_get (inferior_ptid
, 6);
327 i386bsd_dr_get_control (void)
329 return i386bsd_dr_get (inferior_ptid
, 7);
332 #endif /* PT_GETDBREGS */
336 _initialize_i386bsd_nat (void)
340 /* To support the recognition of signal handlers, i386bsd-tdep.c
341 hardcodes some constants. Inclusion of this file means that we
342 are compiling a native debugger, which means that we can use the
343 system header files and sysctl(3) to get at the relevant
346 #if defined (__FreeBSD_version) && __FreeBSD_version >= 400011
347 #define SC_REG_OFFSET i386fbsd4_sc_reg_offset
348 #elif defined (__FreeBSD_version) && __FreeBSD_version >= 300005
349 #define SC_REG_OFFSET i386fbsd_sc_reg_offset
350 #elif defined (NetBSD) || defined (__NetBSD_Version__)
351 #define SC_REG_OFFSET i386nbsd_sc_reg_offset
352 #elif defined (OpenBSD)
353 #define SC_REG_OFFSET i386obsd_sc_reg_offset
358 /* We only check the program counter, stack pointer and frame
359 pointer since these members of `struct sigcontext' are essential
360 for providing backtraces. More checks could be added, but would
361 involve adding configure checks for the appropriate structure
362 members, since older BSD's don't provide all of them. */
364 #define SC_PC_OFFSET SC_REG_OFFSET[I386_EIP_REGNUM]
365 #define SC_SP_OFFSET SC_REG_OFFSET[I386_ESP_REGNUM]
366 #define SC_FP_OFFSET SC_REG_OFFSET[I386_EBP_REGNUM]
368 /* Override the default value for the offset of the program counter
369 in the sigcontext structure. */
370 offset
= offsetof (struct sigcontext
, sc_pc
);
372 if (SC_PC_OFFSET
!= offset
)
375 offsetof (struct sigcontext, sc_pc) yields %d instead of %d.\n\
376 Please report this to <bug-gdb@gnu.org>."),
377 offset
, SC_PC_OFFSET
);
380 SC_PC_OFFSET
= offset
;
382 /* Likewise for the stack pointer. */
383 offset
= offsetof (struct sigcontext
, sc_sp
);
385 if (SC_SP_OFFSET
!= offset
)
388 offsetof (struct sigcontext, sc_sp) yields %d instead of %d.\n\
389 Please report this to <bug-gdb@gnu.org>."),
390 offset
, SC_SP_OFFSET
);
393 SC_SP_OFFSET
= offset
;
395 /* And the frame pointer. */
396 offset
= offsetof (struct sigcontext
, sc_fp
);
398 if (SC_FP_OFFSET
!= offset
)
401 offsetof (struct sigcontext, sc_fp) yields %d instead of %d.\n\
402 Please report this to <bug-gdb@gnu.org>."),
403 offset
, SC_FP_OFFSET
);
406 SC_FP_OFFSET
= offset
;
408 #endif /* SC_REG_OFFSET */