1 /* Target-dependent code for QNX Neutrino x86.
3 Copyright 2003, 2004 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 2 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, write to the Free Software
21 Foundation, Inc., 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 #include "gdb_string.h"
25 #include "gdb_assert.h"
30 #include "solib-svr4.h"
31 #include "i386-tdep.h"
34 #include "i387-tdep.h"
37 #define X86_CPU_FXSR (1L << 12)
40 /* Why 13? Look in our /usr/include/x86/context.h header at the
41 x86_cpu_registers structure and you'll see an 'exx' junk register
42 that is just filler. Don't ask me, ask the kernel guys. */
45 /* Map a GDB register number to an offset in the reg structure. */
46 static int regmap[] = {
56 (10 * 4), /* eflags */
62 static struct nto_target_ops i386_nto_target;
64 /* Given a gdb regno, return the offset into Neutrino's register structure
65 or -1 if register is unknown. */
67 nto_reg_offset (int regno)
69 return (regno >= 0 && regno < NUM_GPREGS) ? regmap[regno] : -1;
73 i386nto_supply_gregset (char *gpregs)
78 for (regno = 0; regno < I386_NUM_GREGS; regno++)
80 int offset = nto_reg_offset (regno);
82 regcache_raw_supply (current_regcache, regno, (char *) &empty);
84 regcache_raw_supply (current_regcache, regno, gpregs + offset);
89 i386nto_supply_fpregset (char *fpregs)
91 if (nto_cpuinfo_valid && nto_cpuinfo_flags | X86_CPU_FXSR)
92 i387_supply_fxsave (current_regcache, -1, fpregs);
94 i387_supply_fsave (current_regcache, -1, fpregs);
98 i386nto_supply_regset (int regset, char *data)
102 case NTO_REG_GENERAL: /* QNX has different ordering of GP regs than GDB. */
103 i386nto_supply_gregset (data);
106 i386nto_supply_fpregset (data);
112 i386nto_regset_id (int regno)
116 else if (regno < I386_NUM_GREGS)
117 return NTO_REG_GENERAL;
118 else if (regno < I386_NUM_GREGS + I386_NUM_FREGS)
119 return NTO_REG_FLOAT;
121 return -1; /* Error. */
125 i386nto_register_area (int regno, int regset, unsigned *off)
130 if (regset == NTO_REG_GENERAL)
133 return NUM_GPREGS * 4;
135 *off = nto_reg_offset (regno);
140 else if (regset == NTO_REG_FLOAT)
142 unsigned off_adjust, regsize, regset_size;
144 if (nto_cpuinfo_valid && nto_cpuinfo_flags | X86_CPU_FXSR)
160 *off = (regno - FP0_REGNUM) * regsize + off_adjust;
162 /* Why 10 instead of regsize? GDB only stores 10 bytes per FP
163 register so if we're sending a register back to the target,
164 we only want pdebug to write 10 bytes so as not to clobber
165 the reserved 6 bytes in the fxsave structure. */
171 i386nto_regset_fill (int regset, char *data)
173 if (regset == NTO_REG_GENERAL)
177 for (regno = 0; regno < NUM_GPREGS; regno++)
179 int offset = nto_reg_offset (regno);
181 regcache_raw_collect (current_regcache, regno, data + offset);
184 else if (regset == NTO_REG_FLOAT)
186 if (nto_cpuinfo_valid && nto_cpuinfo_flags | X86_CPU_FXSR)
187 i387_fill_fxsave (data, -1);
189 i387_fill_fsave (data, -1);
197 static struct link_map_offsets *
198 i386nto_svr4_fetch_link_map_offsets (void)
200 static struct link_map_offsets lmo;
201 static struct link_map_offsets *lmp = NULL;
207 lmo.r_debug_size = 8; /* The actual size is 20 bytes, but
208 only 8 bytes are used. */
209 lmo.r_map_offset = 4;
212 lmo.link_map_size = 20; /* The actual size is 552 bytes, but
213 only 20 bytes are used. */
214 lmo.l_addr_offset = 0;
217 lmo.l_name_offset = 4;
220 lmo.l_next_offset = 12;
223 lmo.l_prev_offset = 16;
230 /* Return whether the frame preceding NEXT_FRAME corresponds to a QNX
231 Neutrino sigtramp routine. */
234 i386nto_sigtramp_p (struct frame_info *next_frame)
236 CORE_ADDR pc = frame_pc_unwind (next_frame);
239 find_pc_partial_function (pc, &name, NULL, NULL);
240 return name && strcmp ("__signalstub", name) == 0;
243 #define I386_NTO_SIGCONTEXT_OFFSET 136
245 /* Assuming NEXT_FRAME is a frame following a QNX Neutrino sigtramp
246 routine, return the address of the associated sigcontext structure. */
249 i386nto_sigcontext_addr (struct frame_info *next_frame)
254 frame_unwind_register (next_frame, I386_ESP_REGNUM, buf);
255 sp = extract_unsigned_integer (buf, 4);
257 return sp + I386_NTO_SIGCONTEXT_OFFSET;
261 init_i386nto_ops (void)
263 i386_nto_target.regset_id = i386nto_regset_id;
264 i386_nto_target.supply_gregset = i386nto_supply_gregset;
265 i386_nto_target.supply_fpregset = i386nto_supply_fpregset;
266 i386_nto_target.supply_altregset = nto_dummy_supply_regset;
267 i386_nto_target.supply_regset = i386nto_supply_regset;
268 i386_nto_target.register_area = i386nto_register_area;
269 i386_nto_target.regset_fill = i386nto_regset_fill;
270 i386_nto_target.fetch_link_map_offsets =
271 i386nto_svr4_fetch_link_map_offsets;
275 i386nto_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
277 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
279 /* Deal with our strange signals. */
280 nto_initialize_signals ();
283 i386_elf_init_abi (info, gdbarch);
285 /* Neutrino rewinds to look more normal. Need to override the i386
286 default which is [unfortunately] to decrement the PC. */
287 set_gdbarch_decr_pc_after_break (gdbarch, 0);
289 /* NTO has shared libraries. */
290 set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
292 tdep->sigtramp_p = i386nto_sigtramp_p;
293 tdep->sigcontext_addr = i386nto_sigcontext_addr;
294 tdep->sc_pc_offset = 56;
295 tdep->sc_sp_offset = 68;
297 /* Setjmp()'s return PC saved in EDX (5). */
298 tdep->jb_pc_offset = 20; /* 5x32 bit ints in. */
300 set_solib_svr4_fetch_link_map_offsets (gdbarch,
301 i386nto_svr4_fetch_link_map_offsets);
303 /* Our loader handles solib relocations slightly differently than svr4. */
304 TARGET_SO_RELOCATE_SECTION_ADDRESSES = nto_relocate_section_addresses;
306 /* Supply a nice function to find our solibs. */
307 TARGET_SO_FIND_AND_OPEN_SOLIB = nto_find_and_open_solib;
309 /* Our linker code is in libc. */
310 TARGET_SO_IN_DYNSYM_RESOLVE_CODE = nto_in_dynsym_resolve_code;
312 nto_set_target (&i386_nto_target);
316 _initialize_i386nto_tdep (void)
319 gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_QNXNTO,
321 gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_elf_flavour,
322 nto_elf_osabi_sniffer);