binutils-gdb/gdb/i386-nto-tdep.c

301 lines
7.7 KiB
C

/* Target-dependent code for QNX Neutrino x86.
Copyright 2003, 2004 Free Software Foundation, Inc.
Contributed by QNX Software Systems Ltd.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include "defs.h"
#include "frame.h"
#include "osabi.h"
#include "regcache.h"
#include "target.h"
#include "gdb_assert.h"
#include "gdb_string.h"
#include "i386-tdep.h"
#include "i387-tdep.h"
#include "nto-tdep.h"
#include "solib-svr4.h"
/* Target vector for QNX NTO x86. */
static struct nto_target_ops i386_nto_target;
#ifndef X86_CPU_FXSR
#define X86_CPU_FXSR (1L << 12)
#endif
/* Why 13? Look in our /usr/include/x86/context.h header at the
x86_cpu_registers structure and you'll see an 'exx' junk register
that is just filler. Don't ask me, ask the kernel guys. */
#define NUM_GPREGS 13
/* Mapping between the general-purpose registers in `struct xxx'
format and GDB's register cache layout. */
/* From <x86/context.h>. */
static int i386nto_gregset_reg_offset[] =
{
7 * 4, /* %eax */
6 * 4, /* %ecx */
5 * 4, /* %edx */
4 * 4, /* %ebx */
11 * 4, /* %esp */
2 * 4, /* %epb */
1 * 4, /* %esi */
0 * 4, /* %edi */
8 * 4, /* %eip */
10 * 4, /* %eflags */
9 * 4, /* %cs */
12 * 4, /* %ss */
-1 /* filler */
};
/* Given a GDB register number REGNUM, return the offset into
Neutrino's register structure or -1 if the register is unknown. */
static int
nto_reg_offset (int regnum)
{
if (regnum >= 0 && regnum < ARRAY_SIZE (i386nto_gregset_reg_offset))
return i386nto_gregset_reg_offset[regnum];
return -1;
}
static void
i386nto_supply_gregset (char *gpregs)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
if(tdep->gregset == NULL)
tdep->gregset = regset_alloc (current_gdbarch, i386_supply_gregset,
i386_collect_gregset);
gdb_assert (tdep->gregset_reg_offset == i386nto_gregset_reg_offset);
tdep->gregset->supply_regset (tdep->gregset, current_regcache, -1,
gpregs, NUM_GPREGS * 4);
}
static void
i386nto_supply_fpregset (char *fpregs)
{
if (nto_cpuinfo_valid && nto_cpuinfo_flags | X86_CPU_FXSR)
i387_supply_fxsave (current_regcache, -1, fpregs);
else
i387_supply_fsave (current_regcache, -1, fpregs);
}
static void
i386nto_supply_regset (int regset, char *data)
{
switch (regset)
{
case NTO_REG_GENERAL:
i386nto_supply_gregset (data);
break;
case NTO_REG_FLOAT:
i386nto_supply_fpregset (data);
break;
}
}
static int
i386nto_regset_id (int regno)
{
if (regno == -1)
return NTO_REG_END;
else if (regno < I386_NUM_GREGS)
return NTO_REG_GENERAL;
else if (regno < I386_NUM_GREGS + I386_NUM_FREGS)
return NTO_REG_FLOAT;
return -1; /* Error. */
}
static int
i386nto_register_area (int regno, int regset, unsigned *off)
{
int len;
*off = 0;
if (regset == NTO_REG_GENERAL)
{
if (regno == -1)
return NUM_GPREGS * 4;
*off = nto_reg_offset (regno);
if (*off == -1)
return 0;
return 4;
}
else if (regset == NTO_REG_FLOAT)
{
unsigned off_adjust, regsize, regset_size;
if (nto_cpuinfo_valid && nto_cpuinfo_flags | X86_CPU_FXSR)
{
off_adjust = 32;
regsize = 16;
regset_size = 512;
}
else
{
off_adjust = 28;
regsize = 10;
regset_size = 128;
}
if (regno == -1)
return regset_size;
*off = (regno - FP0_REGNUM) * regsize + off_adjust;
return 10;
/* Why 10 instead of regsize? GDB only stores 10 bytes per FP
register so if we're sending a register back to the target,
we only want pdebug to write 10 bytes so as not to clobber
the reserved 6 bytes in the fxsave structure. */
}
return -1;
}
static int
i386nto_regset_fill (int regset, char *data)
{
if (regset == NTO_REG_GENERAL)
{
int regno;
for (regno = 0; regno < NUM_GPREGS; regno++)
{
int offset = nto_reg_offset (regno);
if (offset != -1)
regcache_raw_collect (current_regcache, regno, data + offset);
}
}
else if (regset == NTO_REG_FLOAT)
{
if (nto_cpuinfo_valid && nto_cpuinfo_flags | X86_CPU_FXSR)
i387_fill_fxsave (data, -1);
else
i387_fill_fsave (data, -1);
}
else
return -1;
return 0;
}
/* Return whether the frame preceding NEXT_FRAME corresponds to a QNX
Neutrino sigtramp routine. */
static int
i386nto_sigtramp_p (struct frame_info *next_frame)
{
CORE_ADDR pc = frame_pc_unwind (next_frame);
char *name;
find_pc_partial_function (pc, &name, NULL, NULL);
return name && strcmp ("__signalstub", name) == 0;
}
#define I386_NTO_SIGCONTEXT_OFFSET 136
/* Assuming NEXT_FRAME is a frame following a QNX Neutrino sigtramp
routine, return the address of the associated sigcontext structure. */
static CORE_ADDR
i386nto_sigcontext_addr (struct frame_info *next_frame)
{
char buf[4];
CORE_ADDR sp;
frame_unwind_register (next_frame, I386_ESP_REGNUM, buf);
sp = extract_unsigned_integer (buf, 4);
return sp + I386_NTO_SIGCONTEXT_OFFSET;
}
static void
init_i386nto_ops (void)
{
i386_nto_target.regset_id = i386nto_regset_id;
i386_nto_target.supply_gregset = i386nto_supply_gregset;
i386_nto_target.supply_fpregset = i386nto_supply_fpregset;
i386_nto_target.supply_altregset = nto_dummy_supply_regset;
i386_nto_target.supply_regset = i386nto_supply_regset;
i386_nto_target.register_area = i386nto_register_area;
i386_nto_target.regset_fill = i386nto_regset_fill;
i386_nto_target.fetch_link_map_offsets =
svr4_ilp32_fetch_link_map_offsets;
}
static void
i386nto_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
/* Deal with our strange signals. */
nto_initialize_signals ();
/* NTO uses ELF. */
i386_elf_init_abi (info, gdbarch);
/* Neutrino rewinds to look more normal. Need to override the i386
default which is [unfortunately] to decrement the PC. */
set_gdbarch_decr_pc_after_break (gdbarch, 0);
tdep->gregset_reg_offset = i386nto_gregset_reg_offset;
tdep->gregset_num_regs = ARRAY_SIZE (i386nto_gregset_reg_offset);
tdep->sizeof_gregset = NUM_GPREGS * 4;
tdep->sigtramp_p = i386nto_sigtramp_p;
tdep->sigcontext_addr = i386nto_sigcontext_addr;
tdep->sc_pc_offset = 56;
tdep->sc_sp_offset = 68;
/* Setjmp()'s return PC saved in EDX (5). */
tdep->jb_pc_offset = 20; /* 5x32 bit ints in. */
set_solib_svr4_fetch_link_map_offsets
(gdbarch, svr4_ilp32_fetch_link_map_offsets);
/* Our loader handles solib relocations slightly differently than svr4. */
TARGET_SO_RELOCATE_SECTION_ADDRESSES = nto_relocate_section_addresses;
/* Supply a nice function to find our solibs. */
TARGET_SO_FIND_AND_OPEN_SOLIB = nto_find_and_open_solib;
/* Our linker code is in libc. */
TARGET_SO_IN_DYNSYM_RESOLVE_CODE = nto_in_dynsym_resolve_code;
nto_set_target (&i386_nto_target);
}
void
_initialize_i386nto_tdep (void)
{
init_i386nto_ops ();
gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_QNXNTO,
i386nto_init_abi);
gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_elf_flavour,
nto_elf_osabi_sniffer);
}