1 /* Native-dependent code for FreeBSD/amd64.
3 Copyright (C) 2003-2015 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/>. */
26 #include <sys/types.h>
27 #include <sys/ptrace.h>
28 #include <sys/sysctl.h>
30 #include <machine/reg.h>
33 #include "amd64-tdep.h"
34 #include "amd64-nat.h"
35 #include "amd64bsd-nat.h"
39 /* Offset in `struct reg' where MEMBER is stored. */
40 #define REG_OFFSET(member) offsetof (struct reg, member)
42 /* At amd64fbsd64_r_reg_offset[REGNUM] you'll find the offset in
43 `struct reg' location where the GDB register REGNUM is stored.
44 Unsupported registers are marked with `-1'. */
45 static int amd64fbsd64_r_reg_offset
[] =
64 REG_OFFSET (r_rflags
),
74 /* Mapping between the general-purpose registers in FreeBSD/amd64
75 `struct reg' format and GDB's register cache layout for
78 Note that most FreeBSD/amd64 registers are 64-bit, while the
79 FreeBSD/i386 registers are all 32-bit, but since we're
80 little-endian we get away with that. */
82 /* From <machine/reg.h>. */
83 static int amd64fbsd32_r_reg_offset
[I386_NUM_GREGS
] =
85 14 * 8, 13 * 8, /* %eax, %ecx */
86 12 * 8, 11 * 8, /* %edx, %ebx */
87 20 * 8, 10 * 8, /* %esp, %ebp */
88 9 * 8, 8 * 8, /* %esi, %edi */
89 17 * 8, 19 * 8, /* %eip, %eflags */
90 18 * 8, 21 * 8, /* %cs, %ss */
91 -1, -1, -1, -1 /* %ds, %es, %fs, %gs */
95 /* Support for debugging kernel virtual memory images. */
97 #include <machine/pcb.h>
98 #include <osreldate.h>
103 amd64fbsd_supply_pcb (struct regcache
*regcache
, struct pcb
*pcb
)
105 /* The following is true for FreeBSD 5.2:
107 The pcb contains %rip, %rbx, %rsp, %rbp, %r12, %r13, %r14, %r15,
108 %ds, %es, %fs and %gs. This accounts for all callee-saved
109 registers specified by the psABI and then some. Here %esp
110 contains the stack pointer at the point just after the call to
111 cpu_switch(). From this information we reconstruct the register
112 state as it would like when we just returned from cpu_switch(). */
114 /* The stack pointer shouldn't be zero. */
115 if (pcb
->pcb_rsp
== 0)
119 regcache_raw_supply (regcache
, AMD64_RIP_REGNUM
, &pcb
->pcb_rip
);
120 regcache_raw_supply (regcache
, AMD64_RBX_REGNUM
, &pcb
->pcb_rbx
);
121 regcache_raw_supply (regcache
, AMD64_RSP_REGNUM
, &pcb
->pcb_rsp
);
122 regcache_raw_supply (regcache
, AMD64_RBP_REGNUM
, &pcb
->pcb_rbp
);
123 regcache_raw_supply (regcache
, 12, &pcb
->pcb_r12
);
124 regcache_raw_supply (regcache
, 13, &pcb
->pcb_r13
);
125 regcache_raw_supply (regcache
, 14, &pcb
->pcb_r14
);
126 regcache_raw_supply (regcache
, 15, &pcb
->pcb_r15
);
127 #if (__FreeBSD_version < 800075) && (__FreeBSD_kernel_version < 800075)
128 /* struct pcb provides the pcb_ds/pcb_es/pcb_fs/pcb_gs fields only
129 up until __FreeBSD_version 800074: The removal of these fields
130 occurred on 2009-04-01 while the __FreeBSD_version number was
131 bumped to 800075 on 2009-04-06. So 800075 is the closest version
132 number where we should not try to access these fields. */
133 regcache_raw_supply (regcache
, AMD64_DS_REGNUM
, &pcb
->pcb_ds
);
134 regcache_raw_supply (regcache
, AMD64_ES_REGNUM
, &pcb
->pcb_es
);
135 regcache_raw_supply (regcache
, AMD64_FS_REGNUM
, &pcb
->pcb_fs
);
136 regcache_raw_supply (regcache
, AMD64_GS_REGNUM
, &pcb
->pcb_gs
);
143 static void (*super_mourn_inferior
) (struct target_ops
*ops
);
146 amd64fbsd_mourn_inferior (struct target_ops
*ops
)
148 #ifdef HAVE_PT_GETDBREGS
149 x86_cleanup_dregs ();
151 super_mourn_inferior (ops
);
154 /* Provide a prototype to silence -Wmissing-prototypes. */
155 void _initialize_amd64fbsd_nat (void);
158 _initialize_amd64fbsd_nat (void)
160 struct target_ops
*t
;
163 amd64_native_gregset32_reg_offset
= amd64fbsd32_r_reg_offset
;
164 amd64_native_gregset64_reg_offset
= amd64fbsd64_r_reg_offset
;
166 /* Add some extra features to the common *BSD/i386 target. */
167 t
= amd64bsd_target ();
169 #ifdef HAVE_PT_GETDBREGS
171 x86_use_watchpoints (t
);
173 x86_dr_low
.set_control
= amd64bsd_dr_set_control
;
174 x86_dr_low
.set_addr
= amd64bsd_dr_set_addr
;
175 x86_dr_low
.get_addr
= amd64bsd_dr_get_addr
;
176 x86_dr_low
.get_status
= amd64bsd_dr_get_status
;
177 x86_dr_low
.get_control
= amd64bsd_dr_get_control
;
178 x86_set_debug_register_length (8);
180 #endif /* HAVE_PT_GETDBREGS */
182 super_mourn_inferior
= t
->to_mourn_inferior
;
183 t
->to_mourn_inferior
= amd64fbsd_mourn_inferior
;
185 t
->to_pid_to_exec_file
= fbsd_pid_to_exec_file
;
186 t
->to_find_memory_regions
= fbsd_find_memory_regions
;
189 /* Support debugging kernel virtual memory images. */
190 bsd_kvm_add_target (amd64fbsd_supply_pcb
);
192 /* To support the recognition of signal handlers, i386bsd-tdep.c
193 hardcodes some constants. Inclusion of this file means that we
194 are compiling a native debugger, which means that we can use the
195 system header files and sysctl(3) to get at the relevant
198 #define SC_REG_OFFSET amd64fbsd_sc_reg_offset
200 /* We only check the program counter, stack pointer and frame
201 pointer since these members of `struct sigcontext' are essential
202 for providing backtraces. */
204 #define SC_RIP_OFFSET SC_REG_OFFSET[AMD64_RIP_REGNUM]
205 #define SC_RSP_OFFSET SC_REG_OFFSET[AMD64_RSP_REGNUM]
206 #define SC_RBP_OFFSET SC_REG_OFFSET[AMD64_RBP_REGNUM]
208 /* Override the default value for the offset of the program counter
209 in the sigcontext structure. */
210 offset
= offsetof (struct sigcontext
, sc_rip
);
212 if (SC_RIP_OFFSET
!= offset
)
215 offsetof (struct sigcontext, sc_rip) yields %d instead of %d.\n\
216 Please report this to <bug-gdb@gnu.org>."),
217 offset
, SC_RIP_OFFSET
);
220 SC_RIP_OFFSET
= offset
;
222 /* Likewise for the stack pointer. */
223 offset
= offsetof (struct sigcontext
, sc_rsp
);
225 if (SC_RSP_OFFSET
!= offset
)
228 offsetof (struct sigcontext, sc_rsp) yields %d instead of %d.\n\
229 Please report this to <bug-gdb@gnu.org>."),
230 offset
, SC_RSP_OFFSET
);
233 SC_RSP_OFFSET
= offset
;
235 /* And the frame pointer. */
236 offset
= offsetof (struct sigcontext
, sc_rbp
);
238 if (SC_RBP_OFFSET
!= offset
)
241 offsetof (struct sigcontext, sc_rbp) yields %d instead of %d.\n\
242 Please report this to <bug-gdb@gnu.org>."),
243 offset
, SC_RBP_OFFSET
);
246 SC_RBP_OFFSET
= offset
;
248 #ifdef KERN_PROC_SIGTRAMP
249 /* Normally signal frames are detected via amd64fbsd_sigtramp_p.
250 However, FreeBSD 9.2 through 10.1 do not include the page holding
251 the signal code in core dumps. These releases do provide a
252 kern.proc.sigtramp.<pid> sysctl that returns the location of the
253 signal trampoline for a running process. We fetch the location
254 of the current (gdb) process and use this to identify signal
255 frames in core dumps from these releases. Note that this only
256 works for core dumps of 64-bit (FreeBSD/amd64) processes and does
257 not handle core dumps of 32-bit (FreeBSD/i386) processes. */
260 struct kinfo_sigtramp kst
;
265 mib
[2] = KERN_PROC_SIGTRAMP
;
268 if (sysctl (mib
, 4, &kst
, &len
, NULL
, 0) == 0)
270 amd64fbsd_sigtramp_start_addr
= (uintptr_t) kst
.ksigtramp_start
;
271 amd64fbsd_sigtramp_end_addr
= (uintptr_t) kst
.ksigtramp_end
;