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i386-darwin-tdep.c
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1/* Darwin support for GDB, the GNU debugger.
2 Copyright (C) 1997-2023 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. */
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
64
65/* Assuming THIS_FRAME is a Darwin sigtramp routine, return the
66 address of the associated sigcontext structure. */
67
68static CORE_ADDR
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
100int
102 frame_info_ptr this_frame)
103{
104 return i386_sigtramp_p (this_frame);
105}
106
107/* Check whether TYPE is a 128-bit vector (__m128, __m128d or __m128i). */
108
109static int
111{
112 return (type->code () == TYPE_CODE_ARRAY && type->is_vector ()
113 && type->length () == 16);
114}
115
116/* Return the alignment for TYPE when passed as an argument. */
117
118static int
120{
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_CODE_ARRAY && type->is_vector ())
128 return type->length ();
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_CODE_STRUCT
135 || type->code () == TYPE_CODE_UNION)
136 {
137 int i;
138 int res = 4;
139 for (i = 0; i < type->num_fields (); i++)
140 {
141 int align
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
152static CORE_ADDR
154 struct regcache *regcache, CORE_ADDR bp_addr,
155 int nargs, struct value **args, CORE_ADDR sp,
156 function_call_return_method return_method,
157 CORE_ADDR struct_addr)
158{
159 i386_gdbarch_tdep *tdep = gdbarch_tdep<i386_gdbarch_tdep> (gdbarch);
160 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
161 gdb_byte buf[4];
162 int i;
163 int write_pass;
164
165 /* Determine the total space required for arguments and struct
166 return address in a first pass, then push arguments in a second pass. */
167
168 for (write_pass = 0; write_pass < 2; write_pass++)
169 {
170 int args_space = 0;
171 int num_m128 = 0;
172
173 if (return_method == return_method_struct)
174 {
175 if (write_pass)
176 {
177 /* Push value address. */
178 store_unsigned_integer (buf, 4, byte_order, struct_addr);
179 write_memory (sp, buf, 4);
180 }
181 args_space += 4;
182 }
183
184 for (i = 0; i < nargs; i++)
185 {
186 struct type *arg_type = args[i]->enclosing_type ();
187
188 if (i386_m128_p (arg_type) && num_m128 < 4)
189 {
190 if (write_pass)
191 {
192 const gdb_byte *val = args[i]->contents_all ().data ();
193 regcache->raw_write (I387_MM0_REGNUM(tdep) + num_m128, val);
194 }
195 num_m128++;
196 }
197 else
198 {
199 args_space = align_up (args_space,
201 if (write_pass)
202 write_memory (sp + args_space,
203 args[i]->contents_all ().data (),
204 arg_type->length ());
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 (arg_type->length (), 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);
232
233 /* ...and fake a frame pointer. */
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
248static void
250{
251 i386_gdbarch_tdep *tdep = gdbarch_tdep<i386_gdbarch_tdep> (gdbarch);
252
253 /* We support the SSE registers. */
254 tdep->num_xmm_regs = I386_NUM_XREGS - 1;
256
259
260 tdep->struct_return = reg_struct_return;
261
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. */
273
275}
276
277static enum gdb_osabi
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
290void
292{
293 gdbarch_register_osabi_sniffer (bfd_arch_unknown, bfd_target_mach_o_flavour,
295
296 gdbarch_register_osabi (bfd_arch_i386, bfd_mach_i386_i386,
298}
@ reg_struct_return
Definition arm-tdep.h:86
void cooked_write(int regnum, const gdb_byte *buf)
Definition regcache.c:870
void raw_write(int regnum, const gdb_byte *buf)
Definition regcache.c:833
void write_memory(CORE_ADDR memaddr, const bfd_byte *myaddr, ssize_t len)
Definition corefile.c:347
void read_memory(CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
Definition corefile.c:238
static void store_unsigned_integer(gdb_byte *addr, int len, enum bfd_endian byte_order, ULONGEST val)
Definition defs.h:515
static ULONGEST extract_unsigned_integer(gdb::array_view< const gdb_byte > buf, enum bfd_endian byte_order)
Definition defs.h:480
void dwarf2_frame_set_signal_frame_p(struct gdbarch *gdbarch, int(*signal_frame_p)(struct gdbarch *, frame_info_ptr))
Definition frame.c:692
void get_frame_register(frame_info_ptr frame, int regnum, gdb_byte *buf)
Definition frame.c:1263
struct gdbarch * get_frame_arch(frame_info_ptr this_frame)
Definition frame.c:3027
enum bfd_endian gdbarch_byte_order(struct gdbarch *gdbarch)
Definition gdbarch.c:1396
void set_gdbarch_num_regs(struct gdbarch *gdbarch, int num_regs)
Definition gdbarch.c:1941
void set_gdbarch_long_double_bit(struct gdbarch *gdbarch, int long_double_bit)
Definition gdbarch.c:1646
void set_gdbarch_so_ops(struct gdbarch *gdbarch, const struct target_so_ops *so_ops)
Definition gdbarch.c:3380
void set_gdbarch_push_dummy_call(struct gdbarch *gdbarch, gdbarch_push_dummy_call_ftype *push_dummy_call)
function_call_return_method
Definition gdbarch.h:114
@ return_method_struct
Definition gdbarch.h:126
struct type * check_typedef(struct type *type)
Definition gdbtypes.c:2966
static int i386_m128_p(struct type *type)
static void i386_darwin_init_abi(struct gdbarch_info info, struct gdbarch *gdbarch)
static int i386_darwin_arg_type_alignment(struct type *type)
static CORE_ADDR i386_darwin_sigcontext_addr(frame_info_ptr this_frame)
const int i386_darwin_thread_state_num_regs
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, function_call_return_method return_method, CORE_ADDR struct_addr)
int i386_darwin_thread_state_reg_offset[]
static enum gdb_osabi i386_mach_o_osabi_sniffer(bfd *abfd)
int darwin_dwarf_signal_frame_p(struct gdbarch *gdbarch, frame_info_ptr this_frame)
void _initialize_i386_darwin_tdep()
int i386_sigtramp_p(frame_info_ptr this_frame)
Definition i386-tdep.c:4104
#define I386_NUM_XREGS
Definition i386-tdep.h:345
@ I386_EBP_REGNUM
Definition i386-tdep.h:286
@ I386_ESP_REGNUM
Definition i386-tdep.h:285
#define I386_SSE_NUM_REGS
Definition i386-tdep.h:347
#define I387_MM0_REGNUM(tdep)
Definition i387-tdep.h:36
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:146
void gdbarch_register_osabi_sniffer(enum bfd_architecture arch, enum bfd_flavour flavour, enum gdb_osabi(*sniffer_fn)(bfd *))
Definition osabi.c:220
gdb_osabi
Definition osabi.h:25
@ GDB_OSABI_DARWIN
Definition osabi.h:43
@ GDB_OSABI_UNKNOWN
Definition osabi.h:26
const struct target_so_ops darwin_so_ops
struct type * type() const
Definition gdbtypes.h:547
int(* sigtramp_p)(frame_info_ptr)
Definition i386-tdep.h:230
CORE_ADDR(* sigcontext_addr)(frame_info_ptr)
Definition i386-tdep.h:233
type_code code() const
Definition gdbtypes.h:956
ULONGEST length() const
Definition gdbtypes.h:983
struct field & field(int idx) const
Definition gdbtypes.h:1012
bool is_vector() const
Definition gdbtypes.h:1186
unsigned int num_fields() const
Definition gdbtypes.h:994
Definition value.h:130