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 /* Given a gdb regno, return the offset into Neutrino's register structure
63 or -1 if register is unknown. */
65 nto_reg_offset (int regno)
67 return (regno >= 0 && regno < NUM_GPREGS) ? regmap[regno] : -1;
71 i386nto_supply_gregset (char *gpregs)
76 for (regno = 0; regno < I386_NUM_GREGS; regno++)
78 int offset = nto_reg_offset (regno);
80 regcache_raw_supply (current_regcache, regno, (char *) &empty);
82 regcache_raw_supply (current_regcache, regno, gpregs + offset);
87 i386nto_supply_fpregset (char *fpregs)
89 if (nto_cpuinfo_valid && nto_cpuinfo_flags | X86_CPU_FXSR)
90 i387_supply_fxsave (current_regcache, -1, fpregs);
92 i387_supply_fsave (current_regcache, -1, fpregs);
96 i386nto_supply_regset (int regset, char *data)
100 case NTO_REG_GENERAL: /* QNX has different ordering of GP regs than GDB. */
101 i386nto_supply_gregset (data);
104 i386nto_supply_fpregset (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 + I386_NUM_FREGS)
117 return NTO_REG_FLOAT;
119 return -1; /* Error. */
123 i386nto_register_area (int regno, int regset, unsigned *off)
128 if (regset == NTO_REG_GENERAL)
131 return NUM_GPREGS * 4;
133 *off = nto_reg_offset (regno);
138 else if (regset == NTO_REG_FLOAT)
140 unsigned off_adjust, regsize, regset_size;
142 if (nto_cpuinfo_valid && nto_cpuinfo_flags | X86_CPU_FXSR)
158 *off = (regno - FP0_REGNUM) * regsize + off_adjust;
160 /* Why 10 instead of regsize? GDB only stores 10 bytes per FP
161 register so if we're sending a register back to the target,
162 we only want pdebug to write 10 bytes so as not to clobber
163 the reserved 6 bytes in the fxsave structure. */
169 i386nto_regset_fill (int regset, char *data)
171 if (regset == NTO_REG_GENERAL)
175 for (regno = 0; regno < NUM_GPREGS; regno++)
177 int offset = nto_reg_offset (regno);
179 regcache_raw_collect (current_regcache, regno, data + offset);
182 else if (regset == NTO_REG_FLOAT)
184 if (nto_cpuinfo_valid && nto_cpuinfo_flags | X86_CPU_FXSR)
185 i387_fill_fxsave (data, -1);
187 i387_fill_fsave (data, -1);
195 static struct link_map_offsets *
196 i386nto_svr4_fetch_link_map_offsets (void)
198 static struct link_map_offsets lmo;
199 static struct link_map_offsets *lmp = NULL;
205 lmo.r_debug_size = 8; /* The actual size is 20 bytes, but
206 only 8 bytes are used. */
207 lmo.r_map_offset = 4;
210 lmo.link_map_size = 20; /* The actual size is 552 bytes, but
211 only 20 bytes are used. */
212 lmo.l_addr_offset = 0;
215 lmo.l_name_offset = 4;
218 lmo.l_next_offset = 12;
221 lmo.l_prev_offset = 16;
228 /* Return whether the frame preceding NEXT_FRAME corresponds to a QNX
229 Neutrino sigtramp routine. */
232 i386nto_sigtramp_p (struct frame_info *next_frame)
234 CORE_ADDR pc = frame_pc_unwind (next_frame);
237 find_pc_partial_function (pc, &name, NULL, NULL);
238 return name && strcmp ("__signalstub", name) == 0;
241 #define I386_NTO_SIGCONTEXT_OFFSET 136
243 /* Assuming NEXT_FRAME is a frame following a QNX Neutrino sigtramp
244 routine, return the address of the associated sigcontext structure. */
247 i386nto_sigcontext_addr (struct frame_info *next_frame)
252 frame_unwind_register (next_frame, I386_ESP_REGNUM, buf);
253 sp = extract_unsigned_integer (buf, 4);
255 return sp + I386_NTO_SIGCONTEXT_OFFSET;
259 init_i386nto_ops (void)
261 current_nto_target.nto_regset_id = i386nto_regset_id;
262 current_nto_target.nto_supply_gregset = i386nto_supply_gregset;
263 current_nto_target.nto_supply_fpregset = i386nto_supply_fpregset;
264 current_nto_target.nto_supply_altregset = nto_dummy_supply_regset;
265 current_nto_target.nto_supply_regset = i386nto_supply_regset;
266 current_nto_target.nto_register_area = i386nto_register_area;
267 current_nto_target.nto_regset_fill = i386nto_regset_fill;
268 current_nto_target.nto_fetch_link_map_offsets =
269 i386nto_svr4_fetch_link_map_offsets;
273 i386nto_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
275 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
278 i386_elf_init_abi (info, gdbarch);
280 /* Neutrino rewinds to look more normal. Need to override the i386
281 default which is [unfortunately] to decrement the PC. */
282 set_gdbarch_decr_pc_after_break (gdbarch, 0);
284 /* NTO has shared libraries. */
285 set_gdbarch_in_solib_call_trampoline (gdbarch, in_plt_section);
286 set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
288 tdep->sigtramp_p = i386nto_sigtramp_p;
289 tdep->sigcontext_addr = i386nto_sigcontext_addr;
290 tdep->sc_pc_offset = 56;
291 tdep->sc_sp_offset = 68;
293 /* Setjmp()'s return PC saved in EDX (5). */
294 tdep->jb_pc_offset = 20; /* 5x32 bit ints in. */
296 set_solib_svr4_fetch_link_map_offsets (gdbarch,
297 i386nto_svr4_fetch_link_map_offsets);
299 /* Our loader handles solib relocations slightly differently than svr4. */
300 TARGET_SO_RELOCATE_SECTION_ADDRESSES = nto_relocate_section_addresses;
302 /* Supply a nice function to find our solibs. */
303 TARGET_SO_FIND_AND_OPEN_SOLIB = nto_find_and_open_solib;
309 _initialize_i386nto_tdep (void)
311 gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_QNXNTO,