1 /* Native-dependent code for modern i386 BSD's.
2 Copyright 2000, 2001, 2002 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
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 #ifdef HAVE_SYS_PROCFS_H
34 #include <sys/procfs.h>
37 #ifndef HAVE_GREGSET_T
38 typedef struct reg gregset_t
;
41 #ifndef HAVE_FPREGSET_T
42 typedef struct fpreg fpregset_t
;
46 #include "i386-tdep.h"
49 /* In older BSD versions we cannot get at some of the segment
50 registers. FreeBSD for example didn't support the %fs and %gs
51 registers until the 3.0 release. We have autoconf checks for their
52 presence, and deal gracefully with their absence. */
54 /* Registers we shouldn't try to fetch. */
55 #if !defined (CANNOT_FETCH_REGISTER)
56 #define CANNOT_FETCH_REGISTER(regno) cannot_fetch_register (regno)
59 /* Registers we shouldn't try to store. */
60 #if !defined (CANNOT_STORE_REGISTER)
61 #define CANNOT_STORE_REGISTER(regno) cannot_fetch_register (regno)
64 /* Offset to the gregset_t location where REG is stored. */
65 #define REG_OFFSET(reg) offsetof (gregset_t, reg)
67 /* At reg_offset[REGNO] you'll find the offset to the gregset_t
68 location where the GDB register REGNO is stored. Unsupported
69 registers are marked with `-1'. */
70 static int reg_offset
[] =
81 REG_OFFSET (r_eflags
),
86 #ifdef HAVE_STRUCT_REG_R_FS
91 #ifdef HAVE_STRUCT_REG_R_GS
98 #define REG_ADDR(regset, regno) ((char *) (regset) + reg_offset[regno])
100 /* Macro to determine if a register is fetched with PT_GETREGS. */
101 #define GETREGS_SUPPLIES(regno) \
102 ((0 <= (regno) && (regno) <= 15))
104 #ifdef HAVE_PT_GETXMMREGS
105 /* Set to 1 if the kernel supports PT_GETXMMREGS. Initialized to -1
106 so that we try PT_GETXMMREGS the first time around. */
107 static int have_ptrace_xmmregs
= -1;
110 /* Return nonzero if we shouldn't try to fetch register REGNO. */
113 cannot_fetch_register (int regno
)
115 return (reg_offset
[regno
] == -1);
119 /* Transfering the registers between GDB, inferiors and core files. */
121 /* Fill GDB's register array with the general-purpose register values
125 supply_gregset (gregset_t
*gregsetp
)
129 for (i
= 0; i
< I386_NUM_GREGS
; i
++)
131 if (CANNOT_FETCH_REGISTER (i
))
132 supply_register (i
, NULL
);
134 supply_register (i
, REG_ADDR (gregsetp
, i
));
138 /* Fill register REGNO (if it is a general-purpose register) in
139 *GREGSETPS with the value in GDB's register array. If REGNO is -1,
140 do this for all registers. */
143 fill_gregset (gregset_t
*gregsetp
, int regno
)
147 for (i
= 0; i
< I386_NUM_GREGS
; i
++)
148 if ((regno
== -1 || regno
== i
) && ! CANNOT_STORE_REGISTER (i
))
149 regcache_collect (i
, REG_ADDR (gregsetp
, i
));
152 #include "i387-tdep.h"
154 /* Fill GDB's register array with the floating-point register values
158 supply_fpregset (fpregset_t
*fpregsetp
)
160 i387_supply_fsave ((char *) fpregsetp
);
163 /* Fill register REGNO (if it is a floating-point register) in
164 *FPREGSETP with the value in GDB's register array. If REGNO is -1,
165 do this for all registers. */
168 fill_fpregset (fpregset_t
*fpregsetp
, int regno
)
170 i387_fill_fsave ((char *) fpregsetp
, regno
);
173 /* Fetch register REGNO from the inferior. If REGNO is -1, do this
174 for all registers (including the floating point registers). */
177 fetch_inferior_registers (int regno
)
180 if (regno
== -1 || GETREGS_SUPPLIES (regno
))
184 if (ptrace (PT_GETREGS
, PIDGET (inferior_ptid
),
185 (PTRACE_ARG3_TYPE
) &gregs
, 0) == -1)
186 perror_with_name ("Couldn't get registers");
188 supply_gregset (&gregs
);
193 if (regno
== -1 || regno
>= FP0_REGNUM
)
196 #ifdef HAVE_PT_GETXMMREGS
199 if (have_ptrace_xmmregs
!= 0 &&
200 ptrace(PT_GETXMMREGS
, PIDGET (inferior_ptid
),
201 (PTRACE_ARG3_TYPE
) xmmregs
, 0) == 0)
203 have_ptrace_xmmregs
= 1;
204 i387_supply_fxsave (xmmregs
);
208 if (ptrace (PT_GETFPREGS
, PIDGET (inferior_ptid
),
209 (PTRACE_ARG3_TYPE
) &fpregs
, 0) == -1)
210 perror_with_name ("Couldn't get floating point status");
212 supply_fpregset (&fpregs
);
215 if (ptrace (PT_GETFPREGS
, PIDGET (inferior_ptid
),
216 (PTRACE_ARG3_TYPE
) &fpregs
, 0) == -1)
217 perror_with_name ("Couldn't get floating point status");
219 supply_fpregset (&fpregs
);
224 /* Store register REGNO back into the inferior. If REGNO is -1, do
225 this for all registers (including the floating point registers). */
228 store_inferior_registers (int regno
)
231 if (regno
== -1 || GETREGS_SUPPLIES (regno
))
235 if (ptrace (PT_GETREGS
, PIDGET (inferior_ptid
),
236 (PTRACE_ARG3_TYPE
) &gregs
, 0) == -1)
237 perror_with_name ("Couldn't get registers");
239 fill_gregset (&gregs
, regno
);
241 if (ptrace (PT_SETREGS
, PIDGET (inferior_ptid
),
242 (PTRACE_ARG3_TYPE
) &gregs
, 0) == -1)
243 perror_with_name ("Couldn't write registers");
249 if (regno
== -1 || regno
>= FP0_REGNUM
)
252 #ifdef HAVE_PT_GETXMMREGS
255 if (have_ptrace_xmmregs
!= 0 &&
256 ptrace(PT_GETXMMREGS
, PIDGET (inferior_ptid
),
257 (PTRACE_ARG3_TYPE
) xmmregs
, 0) == 0)
259 have_ptrace_xmmregs
= 1;
261 i387_fill_fxsave (xmmregs
, regno
);
263 if (ptrace (PT_SETXMMREGS
, PIDGET (inferior_ptid
),
264 (PTRACE_ARG3_TYPE
) xmmregs
, 0) == -1)
265 perror_with_name ("Couldn't write XMM registers");
269 have_ptrace_xmmregs
= 0;
271 if (ptrace (PT_GETFPREGS
, PIDGET (inferior_ptid
),
272 (PTRACE_ARG3_TYPE
) &fpregs
, 0) == -1)
273 perror_with_name ("Couldn't get floating point status");
275 fill_fpregset (&fpregs
, regno
);
277 if (ptrace (PT_SETFPREGS
, PIDGET (inferior_ptid
),
278 (PTRACE_ARG3_TYPE
) &fpregs
, 0) == -1)
279 perror_with_name ("Couldn't write floating point status");
280 #ifdef HAVE_PT_GETXMMREGS
287 /* Support for debug registers. */
289 #ifdef HAVE_PT_GETDBREGS
291 /* Not all versions of FreeBSD/i386 that support the debug registers
294 #define DBREG_DRX(d, x) ((&d->dr0)[x])
298 i386bsd_dr_set (int regnum
, unsigned int value
)
302 if (ptrace (PT_GETDBREGS
, PIDGET (inferior_ptid
),
303 (PTRACE_ARG3_TYPE
) &dbregs
, 0) == -1)
304 perror_with_name ("Couldn't get debug registers");
306 /* For some mysterious reason, some of the reserved bits in the
307 debug control register get set. Mask these off, otherwise the
308 ptrace call below will fail. */
309 DBREG_DRX ((&dbregs
), 7) &= ~(0x0000fc00);
311 DBREG_DRX ((&dbregs
), regnum
) = value
;
313 if (ptrace (PT_SETDBREGS
, PIDGET (inferior_ptid
),
314 (PTRACE_ARG3_TYPE
) &dbregs
, 0) == -1)
315 perror_with_name ("Couldn't write debug registers");
319 i386bsd_dr_set_control (unsigned long control
)
321 i386bsd_dr_set (7, control
);
325 i386bsd_dr_set_addr (int regnum
, CORE_ADDR addr
)
327 gdb_assert (regnum
>= 0 && regnum
<= 4);
329 i386bsd_dr_set (regnum
, addr
);
333 i386bsd_dr_reset_addr (int regnum
)
335 gdb_assert (regnum
>= 0 && regnum
<= 4);
337 i386bsd_dr_set (regnum
, 0);
341 i386bsd_dr_get_status (void)
345 /* FIXME: kettenis/2001-03-31: Calling perror_with_name if the
346 ptrace call fails breaks debugging remote targets. The correct
347 way to fix this is to add the hardware breakpoint and watchpoint
348 stuff to the target vector. For now, just return zero if the
349 ptrace call fails. */
350 if (ptrace (PT_GETDBREGS
, PIDGET (inferior_ptid
),
351 (PTRACE_ARG3_TYPE
) & dbregs
, 0) == -1)
353 perror_with_name ("Couldn't read debug registers");
358 return DBREG_DRX ((&dbregs
), 6);
361 #endif /* PT_GETDBREGS */
364 /* Support for the user struct. */
366 /* Return the address register REGNO. BLOCKEND is the value of
367 u.u_ar0, which should point to the registers. */
370 register_u_addr (CORE_ADDR blockend
, int regno
)
372 return (CORE_ADDR
) REG_ADDR (blockend
, regno
);
375 #include <sys/param.h>
376 #include <sys/user.h>
378 /* Return the size of the user struct. */
383 return (sizeof (struct user
));
387 _initialize_i386bsd_nat (void)
391 /* To support the recognition of signal handlers, i386bsd-tdep.c
392 hardcodes some constants. Inclusion of this file means that we
393 are compiling a native debugger, which means that we can use the
394 system header files and sysctl(3) to get at the relevant
397 #if defined (__FreeBSD_version) && __FreeBSD_version >= 400011
398 extern int i386fbsd4_sc_reg_offset
[];
399 #define SC_REG_OFFSET i386fbsd4_sc_reg_offset
400 #elif defined (__FreeBSD_version) && __FreeBSD_version >= 300005
401 extern int i386fbsd_sc_reg_offset
[];
402 #define SC_REG_OFFSET i386fbsd_sc_reg_offset
403 #elif defined (NetBSD) || defined (__NetBSD_Version__)
404 extern int i386nbsd_sc_reg_offset
[];
405 #define SC_REG_OFFSET i386nbsd_sc_reg_offset
406 #elif defined (OpenBSD)
407 extern int i386obsd_sc_reg_offset
[];
408 #define SC_REG_OFFSET i386obsd_sc_reg_offset
410 extern int i386bsd_sc_reg_offset
[];
411 #define SC_PC_OFFSET i386bsd_sc_reg_offset
414 /* We only check the program counter, stack pointer and frame
415 pointer since these members of `struct sigcontext' are essential
416 for providing backtraces. More checks could be added, but would
417 involve adding configure checks for the appropriate structure
418 members, since older BSD's don't provide all of them. */
420 #define SC_PC_OFFSET SC_REG_OFFSET[I386_EIP_REGNUM]
421 #define SC_SP_OFFSET SC_REG_OFFSET[I386_ESP_REGNUM]
422 #define SC_FP_OFFSET SC_REG_OFFSET[I386_EBP_REGNUM]
424 /* Override the default value for the offset of the program counter
425 in the sigcontext structure. */
426 offset
= offsetof (struct sigcontext
, sc_pc
);
428 if (SC_PC_OFFSET
!= offset
)
431 offsetof (struct sigcontext, sc_pc) yields %d instead of %d.\n\
432 Please report this to <bug-gdb@gnu.org>.",
433 offset
, SC_PC_OFFSET
);
436 SC_PC_OFFSET
= offset
;
438 /* Likewise for the stack pointer. */
439 offset
= offsetof (struct sigcontext
, sc_sp
);
441 if (SC_SP_OFFSET
!= offset
)
444 offsetof (struct sigcontext, sc_sp) yields %d instead of %d.\n\
445 Please report this to <bug-gdb@gnu.org>.",
446 offset
, SC_SP_OFFSET
);
449 SC_SP_OFFSET
= offset
;
451 /* And the frame pointer. */
452 offset
= offsetof (struct sigcontext
, sc_fp
);
454 if (SC_FP_OFFSET
!= offset
)
457 offsetof (struct sigcontext, sc_fp) yields %d instead of %d.\n\
458 Please report this to <bug-gdb@gnu.org>.",
459 offset
, SC_FP_OFFSET
);
462 SC_FP_OFFSET
= offset
;