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/tmp/gdb-7.10/gdb/i386-darwin-tdep.c
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1 /* Darwin support for GDB, the GNU debugger.
2  Copyright (C) 1997-2015 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 "floatformat.h"
27 #include "symtab.h"
28 #include "regcache.h"
29 #include "libbfd.h"
30 #include "objfiles.h"
31 
32 #include "i387-tdep.h"
33 #include "i386-tdep.h"
34 #include "osabi.h"
35 #include "ui-out.h"
36 #include "i386-darwin-tdep.h"
37 #include "solib.h"
38 #include "solib-darwin.h"
39 #include "dwarf2-frame.h"
40 
41 /* Offsets into the struct i386_thread_state where we'll find the saved regs.
42  From <mach/i386/thread_status.h> and i386-tdep.h. */
44 {
45  0 * 4, /* EAX */
46  2 * 4, /* ECX */
47  3 * 4, /* EDX */
48  1 * 4, /* EBX */
49  7 * 4, /* ESP */
50  6 * 4, /* EBP */
51  5 * 4, /* ESI */
52  4 * 4, /* EDI */
53  10 * 4, /* EIP */
54  9 * 4, /* EFLAGS */
55  11 * 4, /* CS */
56  8 * 4, /* SS */
57  12 * 4, /* DS */
58  13 * 4, /* ES */
59  14 * 4, /* FS */
60  15 * 4 /* GS */
61 };
62 
65 
66 /* Assuming THIS_FRAME is a Darwin sigtramp routine, return the
67  address of the associated sigcontext structure. */
68 
69 static CORE_ADDR
71 {
72  struct gdbarch *gdbarch = get_frame_arch (this_frame);
73  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
74  CORE_ADDR bp;
75  CORE_ADDR si;
76  gdb_byte buf[4];
77 
78  get_frame_register (this_frame, I386_EBP_REGNUM, buf);
79  bp = extract_unsigned_integer (buf, 4, byte_order);
80 
81  /* A pointer to the ucontext is passed as the fourth argument
82  to the signal handler. */
83  read_memory (bp + 24, buf, 4);
84  si = extract_unsigned_integer (buf, 4, byte_order);
85 
86  /* The pointer to mcontext is at offset 28. */
87  read_memory (si + 28, buf, 4);
88 
89  /* First register (eax) is at offset 12. */
90  return extract_unsigned_integer (buf, 4, byte_order) + 12;
91 }
92 
93 /* Return true if the PC of THIS_FRAME is in a signal trampoline which
94  may have DWARF-2 CFI.
95 
96  On Darwin, signal trampolines have DWARF-2 CFI but it has only one FDE
97  that covers only the indirect call to the user handler.
98  Without this function, the frame is recognized as a normal frame which is
99  not expected. */
100 
101 int
103  struct frame_info *this_frame)
104 {
105  return i386_sigtramp_p (this_frame);
106 }
107 
108 /* Check wether TYPE is a 128-bit vector (__m128, __m128d or __m128i). */
109 
110 static int
112 {
113  return (TYPE_CODE (type) == TYPE_CODE_ARRAY && TYPE_VECTOR (type)
114  && TYPE_LENGTH (type) == 16);
115 }
116 
117 /* Return the alignment for TYPE when passed as an argument. */
118 
119 static int
121 {
122  type = check_typedef (type);
123  /* According to Mac OS X ABI document (passing arguments):
124  6. The caller places 64-bit vectors (__m64) on the parameter area,
125  aligned to 8-byte boundaries.
126  7. [...] The caller aligns 128-bit vectors in the parameter area to
127  16-byte boundaries. */
128  if (TYPE_CODE (type) == TYPE_CODE_ARRAY && TYPE_VECTOR (type))
129  return TYPE_LENGTH (type);
130  /* 4. The caller places all the fields of structures (or unions) with no
131  vector elements in the parameter area. These structures are 4-byte
132  aligned.
133  5. The caller places structures with vector elements on the stack,
134  16-byte aligned. */
135  if (TYPE_CODE (type) == TYPE_CODE_STRUCT
136  || TYPE_CODE (type) == TYPE_CODE_UNION)
137  {
138  int i;
139  int res = 4;
140  for (i = 0; i < TYPE_NFIELDS (type); i++)
141  res = max (res,
143  return res;
144  }
145  /* 2. The caller aligns nonvector arguments to 4-byte boundaries. */
146  return 4;
147 }
148 
149 static CORE_ADDR
151  struct regcache *regcache, CORE_ADDR bp_addr,
152  int nargs, struct value **args, CORE_ADDR sp,
153  int struct_return, CORE_ADDR struct_addr)
154 {
155  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
156  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
157  gdb_byte buf[4];
158  int i;
159  int write_pass;
160 
161  /* Determine the total space required for arguments and struct
162  return address in a first pass, then push arguments in a second pass. */
163 
164  for (write_pass = 0; write_pass < 2; write_pass++)
165  {
166  int args_space = 0;
167  int num_m128 = 0;
168 
169  if (struct_return)
170  {
171  if (write_pass)
172  {
173  /* Push value address. */
174  store_unsigned_integer (buf, 4, byte_order, struct_addr);
175  write_memory (sp, buf, 4);
176  }
177  args_space += 4;
178  }
179 
180  for (i = 0; i < nargs; i++)
181  {
182  struct type *arg_type = value_enclosing_type (args[i]);
183 
184  if (i386_m128_p (arg_type) && num_m128 < 4)
185  {
186  if (write_pass)
187  {
188  const gdb_byte *val = value_contents_all (args[i]);
190  (regcache, I387_MM0_REGNUM(tdep) + num_m128, val);
191  }
192  num_m128++;
193  }
194  else
195  {
196  args_space = align_up (args_space,
197  i386_darwin_arg_type_alignment (arg_type));
198  if (write_pass)
199  write_memory (sp + args_space,
200  value_contents_all (args[i]),
201  TYPE_LENGTH (arg_type));
202 
203  /* The System V ABI says that:
204 
205  "An argument's size is increased, if necessary, to make it a
206  multiple of [32-bit] words. This may require tail padding,
207  depending on the size of the argument."
208 
209  This makes sure the stack stays word-aligned. */
210  args_space += align_up (TYPE_LENGTH (arg_type), 4);
211  }
212  }
213 
214  /* Darwin i386 ABI:
215  1. The caller ensures that the stack is 16-byte aligned at the point
216  of the function call. */
217  if (!write_pass)
218  sp = align_down (sp - args_space, 16);
219  }
220 
221  /* Store return address. */
222  sp -= 4;
223  store_unsigned_integer (buf, 4, byte_order, bp_addr);
224  write_memory (sp, buf, 4);
225 
226  /* Finally, update the stack pointer... */
227  store_unsigned_integer (buf, 4, byte_order, sp);
228  regcache_cooked_write (regcache, I386_ESP_REGNUM, buf);
229 
230  /* ...and fake a frame pointer. */
231  regcache_cooked_write (regcache, I386_EBP_REGNUM, buf);
232 
233  /* MarkK wrote: This "+ 8" is all over the place:
234  (i386_frame_this_id, i386_sigtramp_frame_this_id,
235  i386_dummy_id). It's there, since all frame unwinders for
236  a given target have to agree (within a certain margin) on the
237  definition of the stack address of a frame. Otherwise frame id
238  comparison might not work correctly. Since DWARF2/GCC uses the
239  stack address *before* the function call as a frame's CFA. On
240  the i386, when %ebp is used as a frame pointer, the offset
241  between the contents %ebp and the CFA as defined by GCC. */
242  return sp + 8;
243 }
244 
245 static void
247 {
248  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
249 
250  /* We support the SSE registers. */
251  tdep->num_xmm_regs = I386_NUM_XREGS - 1;
253 
256 
258 
259  tdep->sigtramp_p = i386_sigtramp_p;
263 
264  tdep->jb_pc_offset = 48;
265 
266  /* Although the i387 extended floating-point has only 80 significant
267  bits, a `long double' actually takes up 128, probably to enforce
268  alignment. */
269  set_gdbarch_long_double_bit (gdbarch, 128);
270 
271  set_solib_ops (gdbarch, &darwin_so_ops);
272 }
273 
274 static enum gdb_osabi
276 {
277  if (!bfd_check_format (abfd, bfd_object))
278  return GDB_OSABI_UNKNOWN;
279 
280  if (bfd_get_arch (abfd) == bfd_arch_i386)
281  return GDB_OSABI_DARWIN;
282 
283  return GDB_OSABI_UNKNOWN;
284 }
285 
286 /* -Wmissing-prototypes */
288 
289 void
291 {
292  gdbarch_register_osabi_sniffer (bfd_arch_unknown, bfd_target_mach_o_flavour,
294 
295  gdbarch_register_osabi (bfd_arch_i386, bfd_mach_i386_i386,
297 }
void set_gdbarch_num_regs(struct gdbarch *gdbarch, int num_regs)
Definition: gdbarch.c:1909
ULONGEST extract_unsigned_integer(const gdb_byte *, int, enum bfd_endian)
Definition: findvar.c:84
int jb_pc_offset
Definition: i386-tdep.h:199
bfd_vma CORE_ADDR
Definition: common-types.h:41
static CORE_ADDR i386_darwin_sigcontext_addr(struct frame_info *this_frame)
int sc_num_regs
Definition: i386-tdep.h:216
void set_solib_ops(struct gdbarch *gdbarch, const struct target_so_ops *new_ops)
Definition: solib.c:76
#define I386_SSE_NUM_REGS
Definition: i386-tdep.h:323
ULONGEST align_down(ULONGEST v, int n)
Definition: utils.c:2971
#define I386_NUM_XREGS
Definition: i386-tdep.h:321
int i386_sigtramp_p(struct frame_info *this_frame)
Definition: i386-tdep.c:3879
int darwin_dwarf_signal_frame_p(struct gdbarch *gdbarch, struct frame_info *this_frame)
void gdbarch_register_osabi_sniffer(enum bfd_architecture arch, enum bfd_flavour flavour, enum gdb_osabi(*sniffer_fn)(bfd *))
Definition: osabi.c:225
CORE_ADDR(* sigcontext_addr)(struct frame_info *)
Definition: alpha-tdep.h:82
void dwarf2_frame_set_signal_frame_p(struct gdbarch *gdbarch, int(*signal_frame_p)(struct gdbarch *, struct frame_info *))
Definition: dwarf2-frame.c:806
static void i386_darwin_init_abi(struct gdbarch_info info, struct gdbarch *gdbarch)
struct gdbarch_tdep * gdbarch_tdep(struct gdbarch *gdbarch)
Definition: gdbarch.c:1402
#define TYPE_FIELD_TYPE(thistype, n)
Definition: gdbtypes.h:1368
void store_unsigned_integer(gdb_byte *, int, enum bfd_endian, ULONGEST)
Definition: findvar.c:212
struct type * check_typedef(struct type *type)
Definition: gdbtypes.c:2217
enum struct_return struct_return
Definition: arm-tdep.h:197
void initialize_file_ftype(void)
Definition: defs.h:281
struct_return
Definition: arm-tdep.h:148
const gdb_byte * value_contents_all(struct value *value)
Definition: value.c:1188
#define TYPE_VECTOR(t)
Definition: gdbtypes.h:287
struct type * value_enclosing_type(struct value *value)
Definition: value.c:1098
enum bfd_endian gdbarch_byte_order(struct gdbarch *gdbarch)
Definition: gdbarch.c:1420
Definition: gdbtypes.h:749
struct target_so_ops darwin_so_ops
Definition: solib-darwin.c:615
void read_memory(CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
Definition: corefile.c:244
static int i386_m128_p(struct type *type)
Definition: value.c:172
#define I387_MM0_REGNUM(tdep)
Definition: i387-tdep.h:35
initialize_file_ftype _initialize_i386_darwin_tdep
bfd_byte gdb_byte
Definition: common-types.h:38
int(* sigtramp_p)(struct frame_info *)
Definition: i386-tdep.h:209
ULONGEST align_up(ULONGEST v, int n)
Definition: utils.c:2963
#define max(a, b)
Definition: defs.h:109
#define TYPE_CODE(thistype)
Definition: gdbtypes.h:1240
const int i386_darwin_thread_state_num_regs
int num_xmm_regs
Definition: i386-tdep.h:122
void get_frame_register(struct frame_info *frame, int regnum, gdb_byte *buf)
Definition: frame.c:1085
#define TYPE_NFIELDS(thistype)
Definition: gdbtypes.h:1241
int * sc_reg_offset
Definition: i386-tdep.h:215
int i386_darwin_thread_state_reg_offset[]
void set_gdbarch_long_double_bit(struct gdbarch *gdbarch, int long_double_bit)
Definition: gdbarch.c:1667
#define TYPE_LENGTH(thistype)
Definition: gdbtypes.h:1237
static int i386_darwin_arg_type_alignment(struct type *type)
void set_gdbarch_push_dummy_call(struct gdbarch *gdbarch, gdbarch_push_dummy_call_ftype push_dummy_call)
Definition: gdbarch.c:2216
void write_memory(CORE_ADDR memaddr, const bfd_byte *myaddr, ssize_t len)
Definition: corefile.c:389
enum bfd_endian byte_order
Definition: gdbarch.c:128
static enum gdb_osabi i386_mach_o_osabi_sniffer(bfd *abfd)
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:148
struct gdbarch * get_frame_arch(struct frame_info *this_frame)
Definition: frame.c:2535
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)
gdb_osabi
Definition: defs.h:540
void regcache_cooked_write(struct regcache *regcache, int regnum, const gdb_byte *buf)
Definition: regcache.c:930
void regcache_raw_write(struct regcache *regcache, int regnum, const gdb_byte *buf)
Definition: regcache.c:885