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/tmp/gdb-7.10/gdb/mips-sde-tdep.c
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1 /* Target-dependent code for SDE on MIPS processors.
2 
3  Copyright (C) 2014-2015 Free Software Foundation, Inc.
4 
5  This file is part of GDB.
6 
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.
11 
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.
16 
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/>. */
19 
20 #include "defs.h"
21 #include "osabi.h"
22 #include "elf-bfd.h"
23 #include "block.h"
24 #include "symtab.h"
25 
26 #include "frame.h"
27 #include "frame-unwind.h"
28 #include "frame-base.h"
29 #include "trad-frame.h"
30 
31 #include "mips-tdep.h"
32 
33 /* Fill in the register cache *THIS_CACHE for THIS_FRAME for use
34  in the SDE frame unwinder. */
35 
36 static struct trad_frame_cache *
37 mips_sde_frame_cache (struct frame_info *this_frame, void **this_cache)
38 {
39  struct gdbarch *gdbarch = get_frame_arch (this_frame);
40  const struct mips_regnum *regs = mips_regnum (gdbarch);
41  const int sizeof_reg_t = mips_abi_regsize (gdbarch);
42  enum mips_abi abi = mips_abi (gdbarch);
43  struct trad_frame_cache *cache;
44  CORE_ADDR xcpt_frame;
45  CORE_ADDR start_addr;
46  CORE_ADDR stack_addr;
47  CORE_ADDR pc;
48  int i;
49 
50  if (*this_cache != NULL)
51  return *this_cache;
52  cache = trad_frame_cache_zalloc (this_frame);
53  *this_cache = cache;
54 
55  /* The previous registers are held in struct xcptcontext
56  which is at $sp+offs
57 
58  struct xcptcontext {
59  reg_t sr; CP0 Status
60  reg_t cr; CP0 Cause
61  reg_t epc; CP0 EPC
62  reg_t vaddr; CP0 BadVAddr
63  reg_t regs[32]; General registers
64  reg_t mdlo; LO
65  reg_t mdhi; HI
66  reg_t mdex; ACX
67  ...
68  };
69  */
70 
71  stack_addr = get_frame_register_signed (this_frame,
72  gdbarch_sp_regnum (gdbarch));
73  switch (abi)
74  {
75  case MIPS_ABI_O32:
76  /* 40: XCPTCONTEXT
77  24: xcpt_gen() argspace (16 bytes)
78  16: _xcptcall() saved ra, rounded up ( 8 bytes)
79  00: _xcptcall() argspace (16 bytes) */
80  xcpt_frame = stack_addr + 40;
81  break;
82  case MIPS_ABI_N32:
83  case MIPS_ABI_N64:
84  default: /* Wild guess. */
85  /* 16: XCPTCONTEXT
86  16: xcpt_gen() argspace ( 0 bytes)
87  00: _xcptcall() saved ra, rounded up (16 bytes) */
88  xcpt_frame = stack_addr + 16;
89  break;
90  }
91 
93  MIPS_PS_REGNUM + gdbarch_num_regs (gdbarch),
94  xcpt_frame + 0 * sizeof_reg_t);
96  regs->cause + gdbarch_num_regs (gdbarch),
97  xcpt_frame + 1 * sizeof_reg_t);
99  regs->pc + gdbarch_num_regs (gdbarch),
100  xcpt_frame + 2 * sizeof_reg_t);
102  regs->badvaddr + gdbarch_num_regs (gdbarch),
103  xcpt_frame + 3 * sizeof_reg_t);
104  for (i = 0; i < MIPS_NUMREGS; i++)
106  i + MIPS_ZERO_REGNUM + gdbarch_num_regs (gdbarch),
107  xcpt_frame + (4 + i) * sizeof_reg_t);
109  regs->lo + gdbarch_num_regs (gdbarch),
110  xcpt_frame + 36 * sizeof_reg_t);
112  regs->hi + gdbarch_num_regs (gdbarch),
113  xcpt_frame + 37 * sizeof_reg_t);
114 
115  pc = get_frame_pc (this_frame);
116  find_pc_partial_function (pc, NULL, &start_addr, NULL);
117  trad_frame_set_id (cache, frame_id_build (start_addr, stack_addr));
118 
119  return cache;
120 }
121 
122 /* Implement the this_id function for the SDE frame unwinder. */
123 
124 static void
125 mips_sde_frame_this_id (struct frame_info *this_frame, void **this_cache,
126  struct frame_id *this_id)
127 {
128  struct trad_frame_cache *this_trad_cache
129  = mips_sde_frame_cache (this_frame, this_cache);
130 
131  trad_frame_get_id (this_trad_cache, this_id);
132 }
133 
134 /* Implement the prev_register function for the SDE frame unwinder. */
135 
136 static struct value *
138  void **this_cache,
139  int prev_regnum)
140 {
141  struct trad_frame_cache *trad_cache
142  = mips_sde_frame_cache (this_frame, this_cache);
143 
144  return trad_frame_get_register (trad_cache, this_frame, prev_regnum);
145 }
146 
147 /* Implement the sniffer function for the SDE frame unwinder. */
148 
149 static int
151  struct frame_info *this_frame,
152  void **this_cache)
153 {
154  CORE_ADDR pc = get_frame_pc (this_frame);
155  const char *name;
156 
157  find_pc_partial_function (pc, &name, NULL, NULL);
158  return (name
159  && (strcmp (name, "_xcptcall") == 0
160  || strcmp (name, "_sigtramp") == 0));
161 }
162 
163 /* Data structure for the SDE frame unwinder. */
164 
165 static const struct frame_unwind mips_sde_frame_unwind =
166 {
171  NULL,
173 };
174 
175 /* Implement the this_base, this_locals, and this_args hooks
176  for the normal unwinder. */
177 
178 static CORE_ADDR
179 mips_sde_frame_base_address (struct frame_info *this_frame, void **this_cache)
180 {
181  struct trad_frame_cache *this_trad_cache
182  = mips_sde_frame_cache (this_frame, this_cache);
183 
184  return trad_frame_get_this_base (this_trad_cache);
185 }
186 
187 static const struct frame_base mips_sde_frame_base =
188 {
192  mips_sde_frame_base_address
193 };
194 
195 static const struct frame_base *
197 {
198  if (mips_sde_frame_sniffer (&mips_sde_frame_unwind, this_frame, NULL))
199  return &mips_sde_frame_base;
200  else
201  return NULL;
202 }
203 
204 static void
205 mips_sde_elf_osabi_sniff_abi_tag_sections (bfd *abfd, asection *sect,
206  void *obj)
207 {
208  enum gdb_osabi *os_ident_ptr = obj;
209  const char *name;
210 
211  name = bfd_get_section_name (abfd, sect);
212 
213  /* The presence of a section with a ".sde" prefix is indicative
214  of an SDE binary. */
215  if (startswith (name, ".sde"))
216  *os_ident_ptr = GDB_OSABI_SDE;
217 }
218 
219 /* OSABI sniffer for MIPS SDE. */
220 
221 static enum gdb_osabi
223 {
224  enum gdb_osabi osabi = GDB_OSABI_UNKNOWN;
225  unsigned int elfosabi;
226 
227  /* If the generic sniffer gets a hit, return and let other sniffers
228  get a crack at it. */
229  bfd_map_over_sections (abfd,
231  &osabi);
232  if (osabi != GDB_OSABI_UNKNOWN)
233  return GDB_OSABI_UNKNOWN;
234 
235  elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI];
236 
237  if (elfosabi == ELFOSABI_NONE)
238  {
239  /* When elfosabi is ELFOSABI_NONE (0), then the ELF structures in the
240  file are conforming to the base specification for that machine
241  (there are no OS-specific extensions). In order to determine the
242  real OS in use we must look for OS notes that have been added.
243 
244  For SDE, we simply look for sections named with .sde as prefixes. */
245  bfd_map_over_sections (abfd,
247  &osabi);
248  }
249  return osabi;
250 }
251 
252 static void
254 {
255  frame_unwind_append_unwinder (gdbarch, &mips_sde_frame_unwind);
257 }
258 
259 /* Provide a prototype to silence -Wmissing-prototypes. */
261 
262 void
264 {
265  gdbarch_register_osabi_sniffer (bfd_arch_mips,
266  bfd_target_elf_flavour,
268 
270 }
initialize_file_ftype _initialize_mips_sde_tdep
void trad_frame_set_reg_addr(struct trad_frame_cache *this_trad_cache, int regnum, CORE_ADDR addr)
Definition: trad-frame.c:119
struct frame_id frame_id_build(CORE_ADDR stack_addr, CORE_ADDR code_addr)
Definition: frame.c:554
CORE_ADDR get_frame_pc(struct frame_info *frame)
Definition: frame.c:2217
bfd_vma CORE_ADDR
Definition: common-types.h:41
void trad_frame_set_id(struct trad_frame_cache *this_trad_cache, struct frame_id this_id)
Definition: trad-frame.c:164
static CORE_ADDR mips_sde_frame_base_address(struct frame_info *this_frame, void **this_cache)
static struct value * mips_sde_frame_prev_register(struct frame_info *this_frame, void **this_cache, int prev_regnum)
void gdbarch_register_osabi_sniffer(enum bfd_architecture arch, enum bfd_flavour flavour, enum gdb_osabi(*sniffer_fn)(bfd *))
Definition: osabi.c:225
void generic_elf_osabi_sniff_abi_tag_sections(bfd *abfd, asection *sect, void *obj)
Definition: osabi.c:444
int gdbarch_num_regs(struct gdbarch *gdbarch)
Definition: gdbarch.c:1898
const struct mips_regnum * mips_regnum(struct gdbarch *gdbarch)
Definition: mips-tdep.c:199
void frame_unwind_append_unwinder(struct gdbarch *gdbarch, const struct frame_unwind *unwinder)
Definition: frame-unwind.c:78
unsigned int mips_abi_regsize(struct gdbarch *gdbarch)
Definition: mips-tdep.c:258
void trad_frame_get_id(struct trad_frame_cache *this_trad_cache, struct frame_id *this_id)
Definition: trad-frame.c:171
const char *const name
Definition: aarch64-tdep.c:68
void initialize_file_ftype(void)
Definition: defs.h:281
int gdbarch_sp_regnum(struct gdbarch *gdbarch)
Definition: gdbarch.c:1981
static const struct frame_unwind mips_sde_frame_unwind
int badvaddr
Definition: mips-tdep.h:66
int find_pc_partial_function(CORE_ADDR pc, const char **name, CORE_ADDR *address, CORE_ADDR *endaddr)
Definition: blockframe.c:321
LONGEST get_frame_register_signed(struct frame_info *frame, int regnum)
Definition: frame.c:1176
static const struct frame_base mips_sde_frame_base
static int startswith(const char *string, const char *pattern)
Definition: common-utils.h:75
struct trad_frame_cache * trad_frame_cache_zalloc(struct frame_info *this_frame)
Definition: trad-frame.c:36
struct frame_info * this_frame
Definition: trad-frame.c:29
Definition: value.c:172
static struct trad_frame_cache * mips_sde_frame_cache(struct frame_info *this_frame, void **this_cache)
Definition: mips-sde-tdep.c:37
static void mips_sde_frame_this_id(struct frame_info *this_frame, void **this_cache, struct frame_id *this_id)
struct frame_id this_id
Definition: trad-frame.c:32
static void mips_sde_elf_osabi_sniff_abi_tag_sections(bfd *abfd, asection *sect, void *obj)
static enum gdb_osabi mips_sde_elf_osabi_sniffer(bfd *abfd)
mips_abi
Definition: mips-tdep.h:28
void frame_base_append_sniffer(struct gdbarch *gdbarch, frame_base_sniffer_ftype *sniffer)
Definition: frame-base.c:82
enum unwind_stop_reason default_frame_unwind_stop_reason(struct frame_info *this_frame, void **this_cache)
Definition: frame-unwind.c:180
CORE_ADDR trad_frame_get_this_base(struct trad_frame_cache *this_trad_cache)
Definition: trad-frame.c:185
static const struct frame_base * mips_sde_frame_base_sniffer(struct frame_info *this_frame)
static void mips_sde_init_abi(struct gdbarch_info info, struct gdbarch *gdbarch)
struct value * trad_frame_get_register(struct trad_frame_cache *this_trad_cache, struct frame_info *this_frame, int regnum)
Definition: trad-frame.c:155
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
gdb_osabi
Definition: defs.h:540
static int mips_sde_frame_sniffer(const struct frame_unwind *self, struct frame_info *this_frame, void **this_cache)