1 /* Native-dependent code for FreeBSD/amd64.
3 Copyright (C) 2003, 2004, 2007, 2008, 2009 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/>. */
25 #include "gdb_assert.h"
28 #include <sys/types.h>
29 #include <sys/ptrace.h>
30 #include <sys/sysctl.h>
31 #include <machine/reg.h>
34 #include "amd64-tdep.h"
35 #include "amd64-nat.h"
38 /* Offset in `struct reg' where MEMBER is stored. */
39 #define REG_OFFSET(member) offsetof (struct reg, member)
41 /* At amd64fbsd64_r_reg_offset[REGNUM] you'll find the offset in
42 `struct reg' location where the GDB register REGNUM is stored.
43 Unsupported registers are marked with `-1'. */
44 static int amd64fbsd64_r_reg_offset
[] =
63 REG_OFFSET (r_rflags
),
73 /* Mapping between the general-purpose registers in FreeBSD/amd64
74 `struct reg' format and GDB's register cache layout for
77 Note that most FreeBSD/amd64 registers are 64-bit, while the
78 FreeBSD/i386 registers are all 32-bit, but since we're
79 little-endian we get away with that. */
81 /* From <machine/reg.h>. */
82 static int amd64fbsd32_r_reg_offset
[I386_NUM_GREGS
] =
84 14 * 8, 13 * 8, /* %eax, %ecx */
85 12 * 8, 11 * 8, /* %edx, %ebx */
86 20 * 8, 10 * 8, /* %esp, %ebp */
87 9 * 8, 8 * 8, /* %esi, %edi */
88 17 * 8, 19 * 8, /* %eip, %eflags */
89 18 * 8, 21 * 8, /* %cs, %ss */
90 -1, -1, -1, -1 /* %ds, %es, %fs, %gs */
94 /* Support for debugging kernel virtual memory images. */
96 #include <sys/types.h>
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)
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 /* Provide a prototype to silence -Wmissing-prototypes. */
144 void _initialize_amd64fbsd_nat (void);
147 _initialize_amd64fbsd_nat (void)
149 struct target_ops
*t
;
152 amd64_native_gregset32_reg_offset
= amd64fbsd32_r_reg_offset
;
153 amd64_native_gregset64_reg_offset
= amd64fbsd64_r_reg_offset
;
155 /* Add some extra features to the common *BSD/i386 target. */
156 t
= amd64bsd_target ();
157 t
->to_pid_to_exec_file
= fbsd_pid_to_exec_file
;
158 t
->to_find_memory_regions
= fbsd_find_memory_regions
;
159 t
->to_make_corefile_notes
= fbsd_make_corefile_notes
;
162 /* Support debugging kernel virtual memory images. */
163 bsd_kvm_add_target (amd64fbsd_supply_pcb
);
165 /* To support the recognition of signal handlers, i386bsd-tdep.c
166 hardcodes some constants. Inclusion of this file means that we
167 are compiling a native debugger, which means that we can use the
168 system header files and sysctl(3) to get at the relevant
171 #define SC_REG_OFFSET amd64fbsd_sc_reg_offset
173 /* We only check the program counter, stack pointer and frame
174 pointer since these members of `struct sigcontext' are essential
175 for providing backtraces. */
177 #define SC_RIP_OFFSET SC_REG_OFFSET[AMD64_RIP_REGNUM]
178 #define SC_RSP_OFFSET SC_REG_OFFSET[AMD64_RSP_REGNUM]
179 #define SC_RBP_OFFSET SC_REG_OFFSET[AMD64_RBP_REGNUM]
181 /* Override the default value for the offset of the program counter
182 in the sigcontext structure. */
183 offset
= offsetof (struct sigcontext
, sc_rip
);
185 if (SC_RIP_OFFSET
!= offset
)
188 offsetof (struct sigcontext, sc_rip) yields %d instead of %d.\n\
189 Please report this to <bug-gdb@gnu.org>."),
190 offset
, SC_RIP_OFFSET
);
193 SC_RIP_OFFSET
= offset
;
195 /* Likewise for the stack pointer. */
196 offset
= offsetof (struct sigcontext
, sc_rsp
);
198 if (SC_RSP_OFFSET
!= offset
)
201 offsetof (struct sigcontext, sc_rsp) yields %d instead of %d.\n\
202 Please report this to <bug-gdb@gnu.org>."),
203 offset
, SC_RSP_OFFSET
);
206 SC_RSP_OFFSET
= offset
;
208 /* And the frame pointer. */
209 offset
= offsetof (struct sigcontext
, sc_rbp
);
211 if (SC_RBP_OFFSET
!= offset
)
214 offsetof (struct sigcontext, sc_rbp) yields %d instead of %d.\n\
215 Please report this to <bug-gdb@gnu.org>."),
216 offset
, SC_RBP_OFFSET
);
219 SC_RBP_OFFSET
= offset
;
221 /* FreeBSD provides a kern.ps_strings sysctl that we can use to
222 locate the sigtramp. That way we can still recognize a sigtramp
223 if its location is changed in a new kernel. Of course this is
224 still based on the assumption that the sigtramp is placed
225 directly under the location where the program arguments and
226 environment can be found. */
233 mib
[1] = KERN_PS_STRINGS
;
234 len
= sizeof (ps_strings
);
235 if (sysctl (mib
, 2, &ps_strings
, &len
, NULL
, 0) == 0)
237 amd64fbsd_sigtramp_start_addr
= ps_strings
- 32;
238 amd64fbsd_sigtramp_end_addr
= ps_strings
;