1 /* Target-dependent code for QNX Neutrino x86.
3 Copyright (C) 2003-2022 Free Software Foundation, Inc.
5 Contributed by QNX Software Systems Ltd.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
28 #include "i386-tdep.h"
29 #include "i387-tdep.h"
32 #include "solib-svr4.h"
35 #define X86_CPU_FXSR (1L << 12)
38 /* Why 13? Look in our /usr/include/x86/context.h header at the
39 x86_cpu_registers structure and you'll see an 'exx' junk register
40 that is just filler. Don't ask me, ask the kernel guys. */
43 /* Mapping between the general-purpose registers in `struct xxx'
44 format and GDB's register cache layout. */
46 /* From <x86/context.h>. */
47 static int i386nto_gregset_reg_offset
[] =
64 /* Given a GDB register number REGNUM, return the offset into
65 Neutrino's register structure or -1 if the register is unknown. */
68 nto_reg_offset (int regnum
)
70 if (regnum
>= 0 && regnum
< ARRAY_SIZE (i386nto_gregset_reg_offset
))
71 return i386nto_gregset_reg_offset
[regnum
];
77 i386nto_supply_gregset (struct regcache
*regcache
, char *gpregs
)
79 struct gdbarch
*gdbarch
= regcache
->arch ();
80 i386_gdbarch_tdep
*tdep
= gdbarch_tdep
<i386_gdbarch_tdep
> (gdbarch
);
82 gdb_assert (tdep
->gregset_reg_offset
== i386nto_gregset_reg_offset
);
83 i386_gregset
.supply_regset (&i386_gregset
, regcache
, -1,
84 gpregs
, NUM_GPREGS
* 4);
88 i386nto_supply_fpregset (struct regcache
*regcache
, char *fpregs
)
90 if (nto_cpuinfo_valid
&& nto_cpuinfo_flags
| X86_CPU_FXSR
)
91 i387_supply_fxsave (regcache
, -1, fpregs
);
93 i387_supply_fsave (regcache
, -1, fpregs
);
97 i386nto_supply_regset (struct regcache
*regcache
, int regset
, char *data
)
101 case NTO_REG_GENERAL
:
102 i386nto_supply_gregset (regcache
, data
);
105 i386nto_supply_fpregset (regcache
, data
);
111 i386nto_regset_id (int regno
)
115 else if (regno
< I386_NUM_GREGS
)
116 return NTO_REG_GENERAL
;
117 else if (regno
< I386_NUM_GREGS
+ I387_NUM_REGS
)
118 return NTO_REG_FLOAT
;
119 else if (regno
< I386_SSE_NUM_REGS
)
120 return NTO_REG_FLOAT
; /* We store xmm registers in fxsave_area. */
122 return -1; /* Error. */
126 i386nto_register_area (struct gdbarch
*gdbarch
,
127 int regno
, int regset
, unsigned *off
)
129 i386_gdbarch_tdep
*tdep
= gdbarch_tdep
<i386_gdbarch_tdep
> (gdbarch
);
132 if (regset
== NTO_REG_GENERAL
)
135 return NUM_GPREGS
* 4;
137 *off
= nto_reg_offset (regno
);
142 else if (regset
== NTO_REG_FLOAT
)
144 unsigned off_adjust
, regsize
, regset_size
, regno_base
;
145 /* The following are flags indicating number in our fxsave_area. */
146 int first_four
= (regno
>= I387_FCTRL_REGNUM (tdep
)
147 && regno
<= I387_FISEG_REGNUM (tdep
));
148 int second_four
= (regno
> I387_FISEG_REGNUM (tdep
)
149 && regno
<= I387_FOP_REGNUM (tdep
));
150 int st_reg
= (regno
>= I387_ST0_REGNUM (tdep
)
151 && regno
< I387_ST0_REGNUM (tdep
) + 8);
152 int xmm_reg
= (regno
>= I387_XMM0_REGNUM (tdep
)
153 && regno
< I387_MXCSR_REGNUM (tdep
));
155 if (nto_cpuinfo_valid
&& nto_cpuinfo_flags
| X86_CPU_FXSR
)
160 /* fxsave_area structure. */
163 /* fpu_control_word, fpu_status_word, fpu_tag_word, fpu_operand
165 regsize
= 2; /* Two bytes each. */
167 regno_base
= I387_FCTRL_REGNUM (tdep
);
169 else if (second_four
)
171 /* fpu_ip, fpu_cs, fpu_op, fpu_ds registers. */
174 regno_base
= I387_FISEG_REGNUM (tdep
) + 1;
181 regno_base
= I387_ST0_REGNUM (tdep
);
188 regno_base
= I387_XMM0_REGNUM (tdep
);
190 else if (regno
== I387_MXCSR_REGNUM (tdep
))
194 regno_base
= I387_MXCSR_REGNUM (tdep
);
199 gdb_assert (regno
== -1);
202 regsize
= regset_size
;
208 /* fsave_area structure. */
209 if (first_four
|| second_four
)
211 /* fpu_control_word, ... , fpu_ds registers. */
214 regno_base
= I387_FCTRL_REGNUM (tdep
);
218 /* One of ST registers. */
221 regno_base
= I387_ST0_REGNUM (tdep
);
226 gdb_assert (regno
== -1);
229 regsize
= regset_size
;
234 *off
= off_adjust
+ (regno
- regno_base
) * regsize
;
243 i386nto_regset_fill (const struct regcache
*regcache
, int regset
, char *data
)
245 if (regset
== NTO_REG_GENERAL
)
249 for (regno
= 0; regno
< NUM_GPREGS
; regno
++)
251 int offset
= nto_reg_offset (regno
);
253 regcache
->raw_collect (regno
, data
+ offset
);
256 else if (regset
== NTO_REG_FLOAT
)
258 if (nto_cpuinfo_valid
&& nto_cpuinfo_flags
| X86_CPU_FXSR
)
259 i387_collect_fxsave (regcache
, -1, data
);
261 i387_collect_fsave (regcache
, -1, data
);
269 /* Return whether THIS_FRAME corresponds to a QNX Neutrino sigtramp
273 i386nto_sigtramp_p (frame_info_ptr this_frame
)
275 CORE_ADDR pc
= get_frame_pc (this_frame
);
278 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
279 return name
&& strcmp ("__signalstub", name
) == 0;
282 /* Assuming THIS_FRAME is a QNX Neutrino sigtramp routine, return the
283 address of the associated sigcontext structure. */
286 i386nto_sigcontext_addr (frame_info_ptr this_frame
)
288 struct gdbarch
*gdbarch
= get_frame_arch (this_frame
);
289 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
293 /* We store __ucontext_t addr in EDI register. */
294 get_frame_register (this_frame
, I386_EDI_REGNUM
, buf
);
295 ptrctx
= extract_unsigned_integer (buf
, 4, byte_order
);
296 ptrctx
+= 24 /* Context pointer is at this offset. */;
302 init_i386nto_ops (void)
304 nto_regset_id
= i386nto_regset_id
;
305 nto_supply_gregset
= i386nto_supply_gregset
;
306 nto_supply_fpregset
= i386nto_supply_fpregset
;
307 nto_supply_altregset
= nto_dummy_supply_regset
;
308 nto_supply_regset
= i386nto_supply_regset
;
309 nto_register_area
= i386nto_register_area
;
310 nto_regset_fill
= i386nto_regset_fill
;
311 nto_fetch_link_map_offsets
=
312 svr4_ilp32_fetch_link_map_offsets
;
316 i386nto_init_abi (struct gdbarch_info info
, struct gdbarch
*gdbarch
)
318 i386_gdbarch_tdep
*tdep
= gdbarch_tdep
<i386_gdbarch_tdep
> (gdbarch
);
319 static struct target_so_ops nto_svr4_so_ops
;
321 /* Deal with our strange signals. */
322 nto_initialize_signals ();
325 i386_elf_init_abi (info
, gdbarch
);
327 /* Neutrino rewinds to look more normal. Need to override the i386
328 default which is [unfortunately] to decrement the PC. */
329 set_gdbarch_decr_pc_after_break (gdbarch
, 0);
331 tdep
->gregset_reg_offset
= i386nto_gregset_reg_offset
;
332 tdep
->gregset_num_regs
= ARRAY_SIZE (i386nto_gregset_reg_offset
);
333 tdep
->sizeof_gregset
= NUM_GPREGS
* 4;
335 tdep
->sigtramp_p
= i386nto_sigtramp_p
;
336 tdep
->sigcontext_addr
= i386nto_sigcontext_addr
;
337 tdep
->sc_reg_offset
= i386nto_gregset_reg_offset
;
338 tdep
->sc_num_regs
= ARRAY_SIZE (i386nto_gregset_reg_offset
);
340 /* Setjmp()'s return PC saved in EDX (5). */
341 tdep
->jb_pc_offset
= 20; /* 5x32 bit ints in. */
343 set_solib_svr4_fetch_link_map_offsets
344 (gdbarch
, svr4_ilp32_fetch_link_map_offsets
);
346 /* Initialize this lazily, to avoid an initialization order
347 dependency on solib-svr4.c's _initialize routine. */
348 if (nto_svr4_so_ops
.in_dynsym_resolve_code
== NULL
)
350 nto_svr4_so_ops
= svr4_so_ops
;
352 /* Our loader handles solib relocations differently than svr4. */
353 nto_svr4_so_ops
.relocate_section_addresses
354 = nto_relocate_section_addresses
;
356 /* Supply a nice function to find our solibs. */
357 nto_svr4_so_ops
.find_and_open_solib
358 = nto_find_and_open_solib
;
360 /* Our linker code is in libc. */
361 nto_svr4_so_ops
.in_dynsym_resolve_code
362 = nto_in_dynsym_resolve_code
;
364 set_gdbarch_so_ops (gdbarch
, &nto_svr4_so_ops
);
366 set_gdbarch_wchar_bit (gdbarch
, 32);
367 set_gdbarch_wchar_signed (gdbarch
, 0);
370 void _initialize_i386nto_tdep ();
372 _initialize_i386nto_tdep ()
375 gdbarch_register_osabi (bfd_arch_i386
, 0, GDB_OSABI_QNXNTO
,
377 gdbarch_register_osabi_sniffer (bfd_arch_i386
, bfd_target_elf_flavour
,
378 nto_elf_osabi_sniffer
);