1 /* Native-dependent code for modern i386 BSD's.
3 Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2007
4 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 2 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, write to the Free Software
20 Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
27 #include "gdb_assert.h"
30 #include <sys/types.h>
31 #include <sys/ptrace.h>
32 #include <machine/reg.h>
33 #include <machine/frame.h>
35 #include "i386-tdep.h"
36 #include "i387-tdep.h"
37 #include "i386bsd-nat.h"
38 #include "inf-ptrace.h"
41 /* In older BSD versions we cannot get at some of the segment
42 registers. FreeBSD for example didn't support the %fs and %gs
43 registers until the 3.0 release. We have autoconf checks for their
44 presence, and deal gracefully with their absence. */
46 /* Offset in `struct reg' where MEMBER is stored. */
47 #define REG_OFFSET(member) offsetof (struct reg, member)
49 /* At i386bsd_reg_offset[REGNUM] you'll find the offset in `struct
50 reg' where the GDB register REGNUM is stored. Unsupported
51 registers are marked with `-1'. */
52 static int i386bsd_r_reg_offset[] =
63 REG_OFFSET (r_eflags),
68 #ifdef HAVE_STRUCT_REG_R_FS
73 #ifdef HAVE_STRUCT_REG_R_GS
80 /* Macro to determine if a register is fetched with PT_GETREGS. */
81 #define GETREGS_SUPPLIES(regnum) \
82 ((0 <= (regnum) && (regnum) <= 15))
84 #ifdef HAVE_PT_GETXMMREGS
85 /* Set to 1 if the kernel supports PT_GETXMMREGS. Initialized to -1
86 so that we try PT_GETXMMREGS the first time around. */
87 static int have_ptrace_xmmregs = -1;
91 /* Supply the general-purpose registers in GREGS, to REGCACHE. */
94 i386bsd_supply_gregset (struct regcache *regcache, const void *gregs)
96 const char *regs = gregs;
99 for (regnum = 0; regnum < ARRAY_SIZE (i386bsd_r_reg_offset); regnum++)
101 int offset = i386bsd_r_reg_offset[regnum];
104 regcache_raw_supply (regcache, regnum, regs + offset);
108 /* Collect register REGNUM from REGCACHE and store its contents in
109 GREGS. If REGNUM is -1, collect and store all appropriate
113 i386bsd_collect_gregset (const struct regcache *regcache,
114 void *gregs, int regnum)
119 for (i = 0; i < ARRAY_SIZE (i386bsd_r_reg_offset); i++)
121 if (regnum == -1 || regnum == i)
123 int offset = i386bsd_r_reg_offset[i];
126 regcache_raw_collect (regcache, i, regs + offset);
131 /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
132 for all registers (including the floating point registers). */
135 i386bsd_fetch_inferior_registers (struct regcache *regcache, int regnum)
137 if (regnum == -1 || GETREGS_SUPPLIES (regnum))
141 if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
142 (PTRACE_TYPE_ARG3) ®s, 0) == -1)
143 perror_with_name (_("Couldn't get registers"));
145 i386bsd_supply_gregset (regcache, ®s);
150 if (regnum == -1 || regnum >= I386_ST0_REGNUM)
153 #ifdef HAVE_PT_GETXMMREGS
156 if (have_ptrace_xmmregs != 0
157 && ptrace(PT_GETXMMREGS, PIDGET (inferior_ptid),
158 (PTRACE_TYPE_ARG3) xmmregs, 0) == 0)
160 have_ptrace_xmmregs = 1;
161 i387_supply_fxsave (regcache, -1, xmmregs);
165 if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
166 (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
167 perror_with_name (_("Couldn't get floating point status"));
169 i387_supply_fsave (regcache, -1, &fpregs);
172 if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
173 (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
174 perror_with_name (_("Couldn't get floating point status"));
176 i387_supply_fsave (regcache, -1, &fpregs);
181 /* Store register REGNUM back into the inferior. If REGNUM is -1, do
182 this for all registers (including the floating point registers). */
185 i386bsd_store_inferior_registers (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_set (int regnum, unsigned int value)
272 if (ptrace (PT_GETDBREGS, PIDGET (inferior_ptid),
273 (PTRACE_TYPE_ARG3) &dbregs, 0) == -1)
274 perror_with_name (_("Couldn't get debug registers"));
276 /* For some mysterious reason, some of the reserved bits in the
277 debug control register get set. Mask these off, otherwise the
278 ptrace call below will fail. */
279 DBREG_DRX ((&dbregs), 7) &= ~(0x0000fc00);
281 DBREG_DRX ((&dbregs), regnum) = value;
283 if (ptrace (PT_SETDBREGS, PIDGET (inferior_ptid),
284 (PTRACE_TYPE_ARG3) &dbregs, 0) == -1)
285 perror_with_name (_("Couldn't write debug registers"));
289 i386bsd_dr_set_control (unsigned long control)
291 i386bsd_dr_set (7, control);
295 i386bsd_dr_set_addr (int regnum, CORE_ADDR addr)
297 gdb_assert (regnum >= 0 && regnum <= 4);
299 i386bsd_dr_set (regnum, addr);
303 i386bsd_dr_reset_addr (int regnum)
305 gdb_assert (regnum >= 0 && regnum <= 4);
307 i386bsd_dr_set (regnum, 0);
311 i386bsd_dr_get_status (void)
315 /* FIXME: kettenis/2001-03-31: Calling perror_with_name if the
316 ptrace call fails breaks debugging remote targets. The correct
317 way to fix this is to add the hardware breakpoint and watchpoint
318 stuff to the target vector. For now, just return zero if the
319 ptrace call fails. */
320 if (ptrace (PT_GETDBREGS, PIDGET (inferior_ptid),
321 (PTRACE_TYPE_ARG3) &dbregs, 0) == -1)
323 perror_with_name (_("Couldn't read debug registers"));
328 return DBREG_DRX ((&dbregs), 6);
331 #endif /* PT_GETDBREGS */
335 _initialize_i386bsd_nat (void)
339 /* To support the recognition of signal handlers, i386bsd-tdep.c
340 hardcodes some constants. Inclusion of this file means that we
341 are compiling a native debugger, which means that we can use the
342 system header files and sysctl(3) to get at the relevant
345 #if defined (__FreeBSD_version) && __FreeBSD_version >= 400011
346 #define SC_REG_OFFSET i386fbsd4_sc_reg_offset
347 #elif defined (__FreeBSD_version) && __FreeBSD_version >= 300005
348 #define SC_REG_OFFSET i386fbsd_sc_reg_offset
349 #elif defined (NetBSD) || defined (__NetBSD_Version__)
350 #define SC_REG_OFFSET i386nbsd_sc_reg_offset
351 #elif defined (OpenBSD)
352 #define SC_REG_OFFSET i386obsd_sc_reg_offset
357 /* We only check the program counter, stack pointer and frame
358 pointer since these members of `struct sigcontext' are essential
359 for providing backtraces. More checks could be added, but would
360 involve adding configure checks for the appropriate structure
361 members, since older BSD's don't provide all of them. */
363 #define SC_PC_OFFSET SC_REG_OFFSET[I386_EIP_REGNUM]
364 #define SC_SP_OFFSET SC_REG_OFFSET[I386_ESP_REGNUM]
365 #define SC_FP_OFFSET SC_REG_OFFSET[I386_EBP_REGNUM]
367 /* Override the default value for the offset of the program counter
368 in the sigcontext structure. */
369 offset = offsetof (struct sigcontext, sc_pc);
371 if (SC_PC_OFFSET != offset)
374 offsetof (struct sigcontext, sc_pc) yields %d instead of %d.\n\
375 Please report this to <bug-gdb@gnu.org>."),
376 offset, SC_PC_OFFSET);
379 SC_PC_OFFSET = offset;
381 /* Likewise for the stack pointer. */
382 offset = offsetof (struct sigcontext, sc_sp);
384 if (SC_SP_OFFSET != offset)
387 offsetof (struct sigcontext, sc_sp) yields %d instead of %d.\n\
388 Please report this to <bug-gdb@gnu.org>."),
389 offset, SC_SP_OFFSET);
392 SC_SP_OFFSET = offset;
394 /* And the frame pointer. */
395 offset = offsetof (struct sigcontext, sc_fp);
397 if (SC_FP_OFFSET != offset)
400 offsetof (struct sigcontext, sc_fp) yields %d instead of %d.\n\
401 Please report this to <bug-gdb@gnu.org>."),
402 offset, SC_FP_OFFSET);
405 SC_FP_OFFSET = offset;
407 #endif /* SC_REG_OFFSET */