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/tmp/gdb-8.1/gdb/i386-darwin-tdep.c
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1 /* Darwin support for GDB, the GNU debugger.
2 Copyright (C) 1997-2018 Free Software Foundation, Inc.
3
4 Contributed by Apple Computer, Inc.
5
6 This file is part of GDB.
7
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.
12
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.
17
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/>. */
20
21 #include "defs.h"
22 #include "frame.h"
23 #include "inferior.h"
24 #include "gdbcore.h"
25 #include "target.h"
26 #include "symtab.h"
27 #include "regcache.h"
28 #include "objfiles.h"
29
30 #include "i387-tdep.h"
31 #include "i386-tdep.h"
32 #include "osabi.h"
33 #include "ui-out.h"
34 #include "i386-darwin-tdep.h"
35 #include "solib.h"
36 #include "solib-darwin.h"
37 #include "dwarf2-frame.h"
38 #include <algorithm>
39
40 /* Offsets into the struct i386_thread_state where we'll find the saved regs.
41 From <mach/i386/thread_status.h> and i386-tdep.h. */
42 int i386_darwin_thread_state_reg_offset[] =
43 {
44 0 * 4, /* EAX */
45 2 * 4, /* ECX */
46 3 * 4, /* EDX */
47 1 * 4, /* EBX */
48 7 * 4, /* ESP */
49 6 * 4, /* EBP */
50 5 * 4, /* ESI */
51 4 * 4, /* EDI */
52 10 * 4, /* EIP */
53 9 * 4, /* EFLAGS */
54 11 * 4, /* CS */
55 8 * 4, /* SS */
56 12 * 4, /* DS */
57 13 * 4, /* ES */
58 14 * 4, /* FS */
59 15 * 4 /* GS */
60 };
61
62 const int i386_darwin_thread_state_num_regs =
63 ARRAY_SIZE (i386_darwin_thread_state_reg_offset);
64
65 /* Assuming THIS_FRAME is a Darwin sigtramp routine, return the
66 address of the associated sigcontext structure. */
67
68 static CORE_ADDR
69 i386_darwin_sigcontext_addr (struct frame_info *this_frame)
70 {
71 struct gdbarch *gdbarch = get_frame_arch (this_frame);
72 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
73 CORE_ADDR bp;
74 CORE_ADDR si;
75 gdb_byte buf[4];
76
77 get_frame_register (this_frame, I386_EBP_REGNUM, buf);
78 bp = extract_unsigned_integer (buf, 4, byte_order);
79
80 /* A pointer to the ucontext is passed as the fourth argument
81 to the signal handler. */
82 read_memory (bp + 24, buf, 4);
83 si = extract_unsigned_integer (buf, 4, byte_order);
84
85 /* The pointer to mcontext is at offset 28. */
86 read_memory (si + 28, buf, 4);
87
88 /* First register (eax) is at offset 12. */
89 return extract_unsigned_integer (buf, 4, byte_order) + 12;
90 }
91
92 /* Return true if the PC of THIS_FRAME is in a signal trampoline which
93 may have DWARF-2 CFI.
94
95 On Darwin, signal trampolines have DWARF-2 CFI but it has only one FDE
96 that covers only the indirect call to the user handler.
97 Without this function, the frame is recognized as a normal frame which is
98 not expected. */
99
100 int
101 darwin_dwarf_signal_frame_p (struct gdbarch *gdbarch,
102 struct frame_info *this_frame)
103 {
104 return i386_sigtramp_p (this_frame);
105 }
106
107 /* Check wether TYPE is a 128-bit vector (__m128, __m128d or __m128i). */
108
109 static int
110 i386_m128_p (struct type *type)
111 {
112 return (TYPE_CODE (type) == TYPE_CODE_ARRAY && TYPE_VECTOR (type)
113 && TYPE_LENGTH (type) == 16);
114 }
115
116 /* Return the alignment for TYPE when passed as an argument. */
117
118 static int
119 i386_darwin_arg_type_alignment (struct type *type)
120 {
121 type = check_typedef (type);
122 /* According to Mac OS X ABI document (passing arguments):
123 6. The caller places 64-bit vectors (__m64) on the parameter area,
124 aligned to 8-byte boundaries.
125 7. [...] The caller aligns 128-bit vectors in the parameter area to
126 16-byte boundaries. */
127 if (TYPE_CODE (type) == TYPE_CODE_ARRAY && TYPE_VECTOR (type))
128 return TYPE_LENGTH (type);
129 /* 4. The caller places all the fields of structures (or unions) with no
130 vector elements in the parameter area. These structures are 4-byte
131 aligned.
132 5. The caller places structures with vector elements on the stack,
133 16-byte aligned. */
134 if (TYPE_CODE (type) == TYPE_CODE_STRUCT
135 || TYPE_CODE (type) == TYPE_CODE_UNION)
136 {
137 int i;
138 int res = 4;
139 for (i = 0; i < TYPE_NFIELDS (type); i++)
140 {
141 int align
142 = i386_darwin_arg_type_alignment (TYPE_FIELD_TYPE (type, i));
143
144 res = std::max (res, align);
145 }
146 return res;
147 }
148 /* 2. The caller aligns nonvector arguments to 4-byte boundaries. */
149 return 4;
150 }
151
152 static CORE_ADDR
153 i386_darwin_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
154 struct regcache *regcache, CORE_ADDR bp_addr,
155 int nargs, struct value **args, CORE_ADDR sp,
156 int struct_return, CORE_ADDR struct_addr)
157 {
158 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
159 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
160 gdb_byte buf[4];
161 int i;
162 int write_pass;
163
164 /* Determine the total space required for arguments and struct
165 return address in a first pass, then push arguments in a second pass. */
166
167 for (write_pass = 0; write_pass < 2; write_pass++)
168 {
169 int args_space = 0;
170 int num_m128 = 0;
171
172 if (struct_return)
173 {
174 if (write_pass)
175 {
176 /* Push value address. */
177 store_unsigned_integer (buf, 4, byte_order, struct_addr);
178 write_memory (sp, buf, 4);
179 }
180 args_space += 4;
181 }
182
183 for (i = 0; i < nargs; i++)
184 {
185 struct type *arg_type = value_enclosing_type (args[i]);
186
187 if (i386_m128_p (arg_type) && num_m128 < 4)
188 {
189 if (write_pass)
190 {
191 const gdb_byte *val = value_contents_all (args[i]);
192 regcache_raw_write
193 (regcache, I387_MM0_REGNUM(tdep) + num_m128, val);
194 }
195 num_m128++;
196 }
197 else
198 {
199 args_space = align_up (args_space,
200 i386_darwin_arg_type_alignment (arg_type));
201 if (write_pass)
202 write_memory (sp + args_space,
203 value_contents_all (args[i]),
204 TYPE_LENGTH (arg_type));
205
206 /* The System V ABI says that:
207
208 "An argument's size is increased, if necessary, to make it a
209 multiple of [32-bit] words. This may require tail padding,
210 depending on the size of the argument."
211
212 This makes sure the stack stays word-aligned. */
213 args_space += align_up (TYPE_LENGTH (arg_type), 4);
214 }
215 }
216
217 /* Darwin i386 ABI:
218 1. The caller ensures that the stack is 16-byte aligned at the point
219 of the function call. */
220 if (!write_pass)
221 sp = align_down (sp - args_space, 16);
222 }
223
224 /* Store return address. */
225 sp -= 4;
226 store_unsigned_integer (buf, 4, byte_order, bp_addr);
227 write_memory (sp, buf, 4);
228
229 /* Finally, update the stack pointer... */
230 store_unsigned_integer (buf, 4, byte_order, sp);
231 regcache_cooked_write (regcache, I386_ESP_REGNUM, buf);
232
233 /* ...and fake a frame pointer. */
234 regcache_cooked_write (regcache, I386_EBP_REGNUM, buf);
235
236 /* MarkK wrote: This "+ 8" is all over the place:
237 (i386_frame_this_id, i386_sigtramp_frame_this_id,
238 i386_dummy_id). It's there, since all frame unwinders for
239 a given target have to agree (within a certain margin) on the
240 definition of the stack address of a frame. Otherwise frame id
241 comparison might not work correctly. Since DWARF2/GCC uses the
242 stack address *before* the function call as a frame's CFA. On
243 the i386, when %ebp is used as a frame pointer, the offset
244 between the contents %ebp and the CFA as defined by GCC. */
245 return sp + 8;
246 }
247
248 static void
249 i386_darwin_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
250 {
251 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
252
253 /* We support the SSE registers. */
254 tdep->num_xmm_regs = I386_NUM_XREGS - 1;
255 set_gdbarch_num_regs (gdbarch, I386_SSE_NUM_REGS);
256
257 dwarf2_frame_set_signal_frame_p (gdbarch, darwin_dwarf_signal_frame_p);
258 set_gdbarch_push_dummy_call (gdbarch, i386_darwin_push_dummy_call);
259
260 tdep->struct_return = reg_struct_return;
261
262 tdep->sigtramp_p = i386_sigtramp_p;
263 tdep->sigcontext_addr = i386_darwin_sigcontext_addr;
264 tdep->sc_reg_offset = i386_darwin_thread_state_reg_offset;
265 tdep->sc_num_regs = i386_darwin_thread_state_num_regs;
266
267 tdep->jb_pc_offset = 48;
268
269 /* Although the i387 extended floating-point has only 80 significant
270 bits, a `long double' actually takes up 128, probably to enforce
271 alignment. */
272 set_gdbarch_long_double_bit (gdbarch, 128);
273
274 set_solib_ops (gdbarch, &darwin_so_ops);
275 }
276
277 static enum gdb_osabi
278 i386_mach_o_osabi_sniffer (bfd *abfd)
279 {
280 if (!bfd_check_format (abfd, bfd_object))
281 return GDB_OSABI_UNKNOWN;
282
283 if (bfd_get_arch (abfd) == bfd_arch_i386)
284 return GDB_OSABI_DARWIN;
285
286 return GDB_OSABI_UNKNOWN;
287 }
288
289 void
290 _initialize_i386_darwin_tdep (void)
291 {
292 gdbarch_register_osabi_sniffer (bfd_arch_unknown, bfd_target_mach_o_flavour,
293 i386_mach_o_osabi_sniffer);
294
295 gdbarch_register_osabi (bfd_arch_i386, bfd_mach_i386_i386,
296 GDB_OSABI_DARWIN, i386_darwin_init_abi);
297 }
set_gdbarch_num_regs
void set_gdbarch_num_regs(struct gdbarch *gdbarch, int num_regs)
Definition: gdbarch.c:2050
gdbarch
Definition: gdbarch.c:127
TYPE_CODE_ARRAY
Definition: gdbtypes.h:104
gdbarch_tdep::jb_pc_offset
int jb_pc_offset
Definition: i386-tdep.h:210
solib-darwin.h
CORE_ADDR
bfd_vma CORE_ADDR
Definition: common-types.h:41
i386_darwin_sigcontext_addr
static CORE_ADDR i386_darwin_sigcontext_addr(struct frame_info *this_frame)
Definition: i386-darwin-tdep.c:69
gdbarch_tdep::sc_num_regs
int sc_num_regs
Definition: i386-tdep.h:227
set_solib_ops
void set_solib_ops(struct gdbarch *gdbarch, const struct target_so_ops *new_ops)
Definition: solib.c:77
I386_SSE_NUM_REGS
#define I386_SSE_NUM_REGS
Definition: i386-tdep.h:335
value_enclosing_type
struct type * value_enclosing_type(const struct value *value)
Definition: value.c:1175
align_down
ULONGEST align_down(ULONGEST v, int n)
Definition: utils.c:3005
gdbarch_tdep
Definition: aarch64-tdep.h:55
I386_NUM_XREGS
#define I386_NUM_XREGS
Definition: i386-tdep.h:333
i386_sigtramp_p
int i386_sigtramp_p(struct frame_info *this_frame)
Definition: i386-tdep.c:3988
darwin_dwarf_signal_frame_p
int darwin_dwarf_signal_frame_p(struct gdbarch *gdbarch, struct frame_info *this_frame)
Definition: i386-darwin-tdep.c:101
gdbarch_register_osabi_sniffer
void gdbarch_register_osabi_sniffer(enum bfd_architecture arch, enum bfd_flavour flavour, enum gdb_osabi(*sniffer_fn)(bfd *))
Definition: osabi.c:219
gdbarch_tdep::sigcontext_addr
CORE_ADDR(* sigcontext_addr)(struct frame_info *)
Definition: alpha-tdep.h:82
frame_info
Definition: frame.c:85
dwarf2_frame_set_signal_frame_p
void dwarf2_frame_set_signal_frame_p(struct gdbarch *gdbarch, int(*signal_frame_p)(struct gdbarch *, struct frame_info *))
Definition: dwarf2-frame.c:771
i386_darwin_init_abi
static void i386_darwin_init_abi(struct gdbarch_info info, struct gdbarch *gdbarch)
Definition: i386-darwin-tdep.c:249
defs.h
gdbarch_tdep
struct gdbarch_tdep * gdbarch_tdep(struct gdbarch *gdbarch)
Definition: gdbarch.c:1491
TYPE_FIELD_TYPE
#define TYPE_FIELD_TYPE(thistype, n)
Definition: gdbtypes.h:1371
GDB_OSABI_UNKNOWN
Definition: defs.h:512
objfiles.h
symtab.h
extract_bp_kind::bp
check_typedef
struct type * check_typedef(struct type *type)
Definition: gdbtypes.c:2421
gdbarch_tdep::struct_return
enum struct_return struct_return
Definition: arm-tdep.h:137
extract_unsigned_integer
static ULONGEST extract_unsigned_integer(const gdb_byte *addr, int len, enum bfd_endian byte_order)
Definition: defs.h:577
osabi.h
regcache.h
reg_struct_return
Definition: arm-tdep.h:91
struct_return
struct_return
Definition: arm-tdep.h:88
value_contents_all
const gdb_byte * value_contents_all(struct value *value)
Definition: value.c:1265
TYPE_VECTOR
#define TYPE_VECTOR(t)
Definition: gdbtypes.h:252
frame.h
gdbarch_byte_order
enum bfd_endian gdbarch_byte_order(struct gdbarch *gdbarch)
Definition: gdbarch.c:1509
inferior.h
TYPE_CODE_UNION
Definition: gdbtypes.h:107
type
Definition: gdbtypes.h:749
_initialize_i386_darwin_tdep
void _initialize_i386_darwin_tdep(void)
Definition: i386-darwin-tdep.c:290
I386_ESP_REGNUM
Definition: i386-tdep.h:275
darwin_so_ops
struct target_so_ops darwin_so_ops
Definition: solib-darwin.c:649
solib.h
read_memory
void read_memory(CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
Definition: corefile.c:258
GDB_OSABI_DARWIN
Definition: defs.h:527
gdbarch_register_osabi
void gdbarch_register_osabi(enum bfd_architecture arch, unsigned long machine, enum gdb_osabi osabi, void(*init_osabi)(struct gdbarch_info, struct gdbarch *))
Definition: osabi.c:143
TYPE_CODE_STRUCT
Definition: gdbtypes.h:106
i386_m128_p
static int i386_m128_p(struct type *type)
Definition: i386-darwin-tdep.c:110
value
Definition: value.c:169
I387_MM0_REGNUM
#define I387_MM0_REGNUM(tdep)
Definition: i387-tdep.h:35
gdb_byte
bfd_byte gdb_byte
Definition: common-types.h:38
gdbarch_tdep::sigtramp_p
int(* sigtramp_p)(struct frame_info *)
Definition: i386-tdep.h:220
align_up
ULONGEST align_up(ULONGEST v, int n)
Definition: utils.c:2997
dwarf2-frame.h
gdbcore.h
TYPE_CODE
#define TYPE_CODE(thistype)
Definition: gdbtypes.h:1238
i386_darwin_thread_state_num_regs
const int i386_darwin_thread_state_num_regs
Definition: i386-darwin-tdep.c:62
gdbarch_tdep::num_xmm_regs
int num_xmm_regs
Definition: i386-tdep.h:124
i386-darwin-tdep.h
get_frame_register
void get_frame_register(struct frame_info *frame, int regnum, gdb_byte *buf)
Definition: frame.c:1165
TYPE_NFIELDS
#define TYPE_NFIELDS(thistype)
Definition: gdbtypes.h:1239
target.h
gdbarch_tdep::sp
struct m32c_reg * sp
Definition: m32c-tdep.c:119
gdbarch_tdep::sc_reg_offset
int * sc_reg_offset
Definition: i386-tdep.h:226
regcache
Definition: regcache.h:232
i386_darwin_thread_state_reg_offset
int i386_darwin_thread_state_reg_offset[]
Definition: i386-darwin-tdep.c:42
gdbarch_info
Definition: gdbarch.h:1626
set_gdbarch_long_double_bit
void set_gdbarch_long_double_bit(struct gdbarch *gdbarch, int long_double_bit)
Definition: gdbarch.c:1756
TYPE_LENGTH
#define TYPE_LENGTH(thistype)
Definition: gdbtypes.h:1235
i386_darwin_arg_type_alignment
static int i386_darwin_arg_type_alignment(struct type *type)
Definition: i386-darwin-tdep.c:119
set_gdbarch_push_dummy_call
void set_gdbarch_push_dummy_call(struct gdbarch *gdbarch, gdbarch_push_dummy_call_ftype push_dummy_call)
Definition: gdbarch.c:2381
i386-tdep.h
write_memory
void write_memory(CORE_ADDR memaddr, const bfd_byte *myaddr, ssize_t len)
Definition: corefile.c:394
i387-tdep.h
gdbarch::byte_order
enum bfd_endian byte_order
Definition: gdbarch.c:137
i386_mach_o_osabi_sniffer
static enum gdb_osabi i386_mach_o_osabi_sniffer(bfd *abfd)
Definition: i386-darwin-tdep.c:278
get_frame_arch
struct gdbarch * get_frame_arch(struct frame_info *this_frame)
Definition: frame.c:2691
i386_darwin_push_dummy_call
static CORE_ADDR i386_darwin_push_dummy_call(struct gdbarch *gdbarch, struct value *function, struct regcache *regcache, CORE_ADDR bp_addr, int nargs, struct value **args, CORE_ADDR sp, int struct_return, CORE_ADDR struct_addr)
Definition: i386-darwin-tdep.c:153
gdb_osabi
gdb_osabi
Definition: defs.h:508
regcache_cooked_write
void regcache_cooked_write(struct regcache *regcache, int regnum, const gdb_byte *buf)
Definition: regcache.c:873
ui-out.h
store_unsigned_integer
static void store_unsigned_integer(gdb_byte *addr, int len, enum bfd_endian byte_order, ULONGEST val)
Definition: defs.h:604
regcache_raw_write
void regcache_raw_write(struct regcache *regcache, int regnum, const gdb_byte *buf)
Definition: regcache.c:831
I386_EBP_REGNUM
Definition: i386-tdep.h:276