1 /* Target-dependent code for QNX Neutrino x86.
3 Copyright (C) 2003-2024 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/>. */
27 #include "i386-tdep.h"
28 #include "i387-tdep.h"
31 #include "solib-svr4.h"
34 #define X86_CPU_FXSR (1L << 12)
37 /* Why 13? Look in our /usr/include/x86/context.h header at the
38 x86_cpu_registers structure and you'll see an 'exx' junk register
39 that is just filler. Don't ask me, ask the kernel guys. */
42 /* Mapping between the general-purpose registers in `struct xxx'
43 format and GDB's register cache layout. */
45 /* From <x86/context.h>. */
46 static int i386nto_gregset_reg_offset
[] =
63 /* Given a GDB register number REGNUM, return the offset into
64 Neutrino's register structure or -1 if the register is unknown. */
67 nto_reg_offset (int regnum
)
69 if (regnum
>= 0 && regnum
< ARRAY_SIZE (i386nto_gregset_reg_offset
))
70 return i386nto_gregset_reg_offset
[regnum
];
76 i386nto_supply_gregset (struct regcache
*regcache
, char *gpregs
)
78 struct gdbarch
*gdbarch
= regcache
->arch ();
79 i386_gdbarch_tdep
*tdep
= gdbarch_tdep
<i386_gdbarch_tdep
> (gdbarch
);
81 gdb_assert (tdep
->gregset_reg_offset
== i386nto_gregset_reg_offset
);
82 i386_gregset
.supply_regset (&i386_gregset
, regcache
, -1,
83 gpregs
, NUM_GPREGS
* 4);
87 i386nto_supply_fpregset (struct regcache
*regcache
, char *fpregs
)
89 if (nto_cpuinfo_valid
&& nto_cpuinfo_flags
| X86_CPU_FXSR
)
90 i387_supply_fxsave (regcache
, -1, fpregs
);
92 i387_supply_fsave (regcache
, -1, fpregs
);
96 i386nto_supply_regset (struct regcache
*regcache
, int regset
, char *data
)
100 case NTO_REG_GENERAL
:
101 i386nto_supply_gregset (regcache
, data
);
104 i386nto_supply_fpregset (regcache
, data
);
110 i386nto_regset_id (int regno
)
114 else if (regno
< I386_NUM_GREGS
)
115 return NTO_REG_GENERAL
;
116 else if (regno
< I386_NUM_GREGS
+ I387_NUM_REGS
)
117 return NTO_REG_FLOAT
;
118 else if (regno
< I386_SSE_NUM_REGS
)
119 return NTO_REG_FLOAT
; /* We store xmm registers in fxsave_area. */
121 return -1; /* Error. */
125 i386nto_register_area (struct gdbarch
*gdbarch
,
126 int regno
, int regset
, unsigned *off
)
128 i386_gdbarch_tdep
*tdep
= gdbarch_tdep
<i386_gdbarch_tdep
> (gdbarch
);
131 if (regset
== NTO_REG_GENERAL
)
134 return NUM_GPREGS
* 4;
136 *off
= nto_reg_offset (regno
);
141 else if (regset
== NTO_REG_FLOAT
)
143 unsigned off_adjust
, regsize
, regset_size
, regno_base
;
144 /* The following are flags indicating number in our fxsave_area. */
145 int first_four
= (regno
>= I387_FCTRL_REGNUM (tdep
)
146 && regno
<= I387_FISEG_REGNUM (tdep
));
147 int second_four
= (regno
> I387_FISEG_REGNUM (tdep
)
148 && regno
<= I387_FOP_REGNUM (tdep
));
149 int st_reg
= (regno
>= I387_ST0_REGNUM (tdep
)
150 && regno
< I387_ST0_REGNUM (tdep
) + 8);
151 int xmm_reg
= (regno
>= I387_XMM0_REGNUM (tdep
)
152 && regno
< I387_MXCSR_REGNUM (tdep
));
154 if (nto_cpuinfo_valid
&& nto_cpuinfo_flags
| X86_CPU_FXSR
)
159 /* fxsave_area structure. */
162 /* fpu_control_word, fpu_status_word, fpu_tag_word, fpu_operand
164 regsize
= 2; /* Two bytes each. */
166 regno_base
= I387_FCTRL_REGNUM (tdep
);
168 else if (second_four
)
170 /* fpu_ip, fpu_cs, fpu_op, fpu_ds registers. */
173 regno_base
= I387_FISEG_REGNUM (tdep
) + 1;
180 regno_base
= I387_ST0_REGNUM (tdep
);
187 regno_base
= I387_XMM0_REGNUM (tdep
);
189 else if (regno
== I387_MXCSR_REGNUM (tdep
))
193 regno_base
= I387_MXCSR_REGNUM (tdep
);
198 gdb_assert (regno
== -1);
201 regsize
= regset_size
;
207 /* fsave_area structure. */
208 if (first_four
|| second_four
)
210 /* fpu_control_word, ... , fpu_ds registers. */
213 regno_base
= I387_FCTRL_REGNUM (tdep
);
217 /* One of ST registers. */
220 regno_base
= I387_ST0_REGNUM (tdep
);
225 gdb_assert (regno
== -1);
228 regsize
= regset_size
;
233 *off
= off_adjust
+ (regno
- regno_base
) * regsize
;
242 i386nto_regset_fill (const struct regcache
*regcache
, int regset
, char *data
)
244 if (regset
== NTO_REG_GENERAL
)
248 for (regno
= 0; regno
< NUM_GPREGS
; regno
++)
250 int offset
= nto_reg_offset (regno
);
252 regcache
->raw_collect (regno
, data
+ offset
);
255 else if (regset
== NTO_REG_FLOAT
)
257 if (nto_cpuinfo_valid
&& nto_cpuinfo_flags
| X86_CPU_FXSR
)
258 i387_collect_fxsave (regcache
, -1, data
);
260 i387_collect_fsave (regcache
, -1, data
);
268 /* Return whether THIS_FRAME corresponds to a QNX Neutrino sigtramp
272 i386nto_sigtramp_p (const frame_info_ptr
&this_frame
)
274 CORE_ADDR pc
= get_frame_pc (this_frame
);
277 find_pc_partial_function (pc
, &name
, NULL
, NULL
);
278 return name
&& strcmp ("__signalstub", name
) == 0;
281 /* Assuming THIS_FRAME is a QNX Neutrino sigtramp routine, return the
282 address of the associated sigcontext structure. */
285 i386nto_sigcontext_addr (const frame_info_ptr
&this_frame
)
287 struct gdbarch
*gdbarch
= get_frame_arch (this_frame
);
288 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
292 /* We store __ucontext_t addr in EDI register. */
293 get_frame_register (this_frame
, I386_EDI_REGNUM
, buf
);
294 ptrctx
= extract_unsigned_integer (buf
, 4, byte_order
);
295 ptrctx
+= 24 /* Context pointer is at this offset. */;
301 init_i386nto_ops (void)
303 nto_regset_id
= i386nto_regset_id
;
304 nto_supply_gregset
= i386nto_supply_gregset
;
305 nto_supply_fpregset
= i386nto_supply_fpregset
;
306 nto_supply_altregset
= nto_dummy_supply_regset
;
307 nto_supply_regset
= i386nto_supply_regset
;
308 nto_register_area
= i386nto_register_area
;
309 nto_regset_fill
= i386nto_regset_fill
;
310 nto_fetch_link_map_offsets
=
311 svr4_ilp32_fetch_link_map_offsets
;
315 i386nto_init_abi (struct gdbarch_info info
, struct gdbarch
*gdbarch
)
317 i386_gdbarch_tdep
*tdep
= gdbarch_tdep
<i386_gdbarch_tdep
> (gdbarch
);
318 static solib_ops nto_svr4_so_ops
;
320 /* Deal with our strange signals. */
321 nto_initialize_signals ();
324 i386_elf_init_abi (info
, gdbarch
);
326 /* Neutrino rewinds to look more normal. Need to override the i386
327 default which is [unfortunately] to decrement the PC. */
328 set_gdbarch_decr_pc_after_break (gdbarch
, 0);
330 tdep
->gregset_reg_offset
= i386nto_gregset_reg_offset
;
331 tdep
->gregset_num_regs
= ARRAY_SIZE (i386nto_gregset_reg_offset
);
332 tdep
->sizeof_gregset
= NUM_GPREGS
* 4;
334 tdep
->sigtramp_p
= i386nto_sigtramp_p
;
335 tdep
->sigcontext_addr
= i386nto_sigcontext_addr
;
336 tdep
->sc_reg_offset
= i386nto_gregset_reg_offset
;
337 tdep
->sc_num_regs
= ARRAY_SIZE (i386nto_gregset_reg_offset
);
339 /* Setjmp()'s return PC saved in EDX (5). */
340 tdep
->jb_pc_offset
= 20; /* 5x32 bit ints in. */
342 set_solib_svr4_fetch_link_map_offsets
343 (gdbarch
, svr4_ilp32_fetch_link_map_offsets
);
345 /* Initialize this lazily, to avoid an initialization order
346 dependency on solib-svr4.c's _initialize routine. */
347 if (nto_svr4_so_ops
.in_dynsym_resolve_code
== NULL
)
349 nto_svr4_so_ops
= svr4_so_ops
;
351 /* Our loader handles solib relocations differently than svr4. */
352 nto_svr4_so_ops
.relocate_section_addresses
353 = nto_relocate_section_addresses
;
355 /* Supply a nice function to find our solibs. */
356 nto_svr4_so_ops
.find_and_open_solib
357 = nto_find_and_open_solib
;
359 /* Our linker code is in libc. */
360 nto_svr4_so_ops
.in_dynsym_resolve_code
361 = nto_in_dynsym_resolve_code
;
363 set_gdbarch_so_ops (gdbarch
, &nto_svr4_so_ops
);
365 set_gdbarch_wchar_bit (gdbarch
, 32);
366 set_gdbarch_wchar_signed (gdbarch
, 0);
369 void _initialize_i386nto_tdep ();
371 _initialize_i386nto_tdep ()
374 gdbarch_register_osabi (bfd_arch_i386
, 0, GDB_OSABI_QNXNTO
,
376 gdbarch_register_osabi_sniffer (bfd_arch_i386
, bfd_target_elf_flavour
,
377 nto_elf_osabi_sniffer
);