-/* Target-dependent code for NetBSD/i386, for GDB.
- Copyright 1988, 1989, 1991, 1992, 1994, 1996, 2000, 2001, 2002
+/* Target-dependent code for NetBSD/i386.
+
+ Copyright 1988, 1989, 1991, 1992, 1994, 1996, 2000, 2001, 2002,
+ 2003, 2004
Free Software Foundation, Inc.
This file is part of GDB.
Boston, MA 02111-1307, USA. */
#include "defs.h"
-#include "gdbtypes.h"
+#include "arch-utils.h"
+#include "frame.h"
#include "gdbcore.h"
#include "regcache.h"
+#include "regset.h"
+#include "osabi.h"
+#include "symtab.h"
+
+#include "gdb_assert.h"
+#include "gdb_string.h"
+#include "i386-tdep.h"
#include "i387-tdep.h"
+#include "nbsd-tdep.h"
+#include "solib-svr4.h"
-/* Map a GDB register number to an offset in the reg structure. */
-static int regmap[] =
+/* From <machine/reg.h>. */
+static int i386nbsd_r_reg_offset[] =
{
- ( 0 * 4), /* %eax */
- ( 1 * 4), /* %ecx */
- ( 2 * 4), /* %edx */
- ( 3 * 4), /* %ebx */
- ( 4 * 4), /* %esp */
- ( 5 * 4), /* %epb */
- ( 6 * 4), /* %esi */
- ( 7 * 4), /* %edi */
- ( 8 * 4), /* %eip */
- ( 9 * 4), /* %eflags */
- (10 * 4), /* %cs */
- (11 * 4), /* %ss */
- (12 * 4), /* %ds */
- (13 * 4), /* %es */
- (14 * 4), /* %fs */
- (15 * 4), /* %gs */
+ 0 * 4, /* %eax */
+ 1 * 4, /* %ecx */
+ 2 * 4, /* %edx */
+ 3 * 4, /* %ebx */
+ 4 * 4, /* %esp */
+ 5 * 4, /* %ebp */
+ 6 * 4, /* %esi */
+ 7 * 4, /* %edi */
+ 8 * 4, /* %eip */
+ 9 * 4, /* %eflags */
+ 10 * 4, /* %cs */
+ 11 * 4, /* %ss */
+ 12 * 4, /* %ds */
+ 13 * 4, /* %es */
+ 14 * 4, /* %fs */
+ 15 * 4 /* %gs */
};
-#define SIZEOF_STRUCT_REG (16 * 4)
-
static void
-i386nbsd_supply_reg (char *regs, int regno)
+i386nbsd_aout_supply_regset (const struct regset *regset,
+ struct regcache *regcache, int regnum,
+ const void *regs, size_t len)
{
- int i;
+ const struct gdbarch_tdep *tdep = gdbarch_tdep (regset->arch);
- for (i = 0; i <= 15; i++)
- if (regno == i || regno == -1)
- supply_register (i, regs + regmap[i]);
+ gdb_assert (len >= tdep->sizeof_gregset + I387_SIZEOF_FSAVE);
+
+ i386_supply_gregset (regset, regcache, regnum, regs, tdep->sizeof_gregset);
+ i387_supply_fsave (regcache, regnum, (char *) regs + tdep->sizeof_gregset);
}
-static void
-fetch_core_registers (char *core_reg_sect, unsigned core_reg_size, int which,
- CORE_ADDR ignore)
+static const struct regset *
+i386nbsd_aout_regset_from_core_section (struct gdbarch *gdbarch,
+ const char *sect_name,
+ size_t sect_size)
{
- char *regs, *fsave;
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
- /* We get everything from one section. */
- if (which != 0)
- return;
+ /* NetBSD a.out core dumps don't use seperate register sets for the
+ general-purpose and floating-point registers. */
- if (core_reg_size < (SIZEOF_STRUCT_REG + 108))
+ if (strcmp (sect_name, ".reg") == 0
+ && sect_size >= tdep->sizeof_gregset + I387_SIZEOF_FSAVE)
{
- warning ("Wrong size register set in core file.");
- return;
+ if (tdep->gregset == NULL)
+ tdep->gregset =
+ regset_alloc (gdbarch, i386nbsd_aout_supply_regset, NULL);
+ return tdep->gregset;
}
- regs = core_reg_sect;
- fsave = core_reg_sect + SIZEOF_STRUCT_REG;
+ return NULL;
+}
+
+/* Under NetBSD/i386, signal handler invocations can be identified by the
+ designated code sequence that is used to return from a signal handler.
+ In particular, the return address of a signal handler points to the
+ following code sequence:
- /* Integer registers. */
- i386nbsd_supply_reg (regs, -1);
+ leal 0x10(%esp), %eax
+ pushl %eax
+ pushl %eax
+ movl $0x127, %eax # __sigreturn14
+ int $0x80
- /* Floating point registers. */
- i387_supply_fsave (fsave);
-}
+ Each instruction has a unique encoding, so we simply attempt to match
+ the instruction the PC is pointing to with any of the above instructions.
+ If there is a hit, we know the offset to the start of the designated
+ sequence and can then check whether we really are executing in the
+ signal trampoline. If not, -1 is returned, otherwise the offset from the
+ start of the return sequence is returned. */
+#define RETCODE_INSN1 0x8d
+#define RETCODE_INSN2 0x50
+#define RETCODE_INSN3 0x50
+#define RETCODE_INSN4 0xb8
+#define RETCODE_INSN5 0xcd
-static void
-fetch_elfcore_registers (char *core_reg_sect, unsigned core_reg_size,
- int which, CORE_ADDR ignore)
+#define RETCODE_INSN2_OFF 4
+#define RETCODE_INSN3_OFF 5
+#define RETCODE_INSN4_OFF 6
+#define RETCODE_INSN5_OFF 11
+
+static const unsigned char sigtramp_retcode[] =
+{
+ RETCODE_INSN1, 0x44, 0x24, 0x10,
+ RETCODE_INSN2,
+ RETCODE_INSN3,
+ RETCODE_INSN4, 0x27, 0x01, 0x00, 0x00,
+ RETCODE_INSN5, 0x80,
+};
+
+static LONGEST
+i386nbsd_sigtramp_offset (struct frame_info *next_frame)
{
- switch (which)
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
+ unsigned char ret[sizeof(sigtramp_retcode)], insn;
+ LONGEST off;
+ int i;
+
+ if (!safe_frame_unwind_memory (next_frame, pc, &insn, 1))
+ return -1;
+
+ switch (insn)
{
- case 0: /* Integer registers. */
- if (core_reg_size != SIZEOF_STRUCT_REG)
- warning ("Wrong size register set in core file.");
- else
- i386nbsd_supply_reg (core_reg_sect, -1);
+ case RETCODE_INSN1:
+ off = 0;
break;
- case 2: /* Floating point registers. */
- if (core_reg_size != 108)
- warning ("Wrong size FP register set in core file.");
+ case RETCODE_INSN2:
+ /* INSN2 and INSN3 are the same. Read at the location of PC+1
+ to determine if we're actually looking at INSN2 or INSN3. */
+ if (!safe_frame_unwind_memory (next_frame, pc + 1, &insn, 1))
+ return -1;
+
+ if (insn == RETCODE_INSN3)
+ off = RETCODE_INSN2_OFF;
else
- i387_supply_fsave (core_reg_sect);
+ off = RETCODE_INSN3_OFF;
break;
- case 3: /* "Extended" floating point registers. This is gdb-speak
- for SSE/SSE2. */
- if (core_reg_size != 512)
- warning ("Wrong size XMM register set in core file.");
- else
- i387_supply_fxsave (core_reg_sect);
+ case RETCODE_INSN4:
+ off = RETCODE_INSN4_OFF;
break;
- default:
- /* Don't know what kind of register request this is; just ignore it. */
+ case RETCODE_INSN5:
+ off = RETCODE_INSN5_OFF;
break;
+
+ default:
+ return -1;
}
+
+ pc -= off;
+
+ if (!safe_frame_unwind_memory (next_frame, pc, ret, sizeof (ret)))
+ return -1;
+
+ if (memcmp (ret, sigtramp_retcode, sizeof (ret)) == 0)
+ return off;
+
+ return -1;
}
-static struct core_fns i386nbsd_core_fns =
+/* Return whether the frame preceding NEXT_FRAME corresponds to a
+ NetBSD sigtramp routine. */
+
+static int
+i386nbsd_sigtramp_p (struct frame_info *next_frame)
{
- bfd_target_unknown_flavour, /* core_flavour */
- default_check_format, /* check_format */
- default_core_sniffer, /* core_sniffer */
- fetch_core_registers, /* core_read_registers */
- NULL /* next */
-};
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
+ char *name;
+
+ find_pc_partial_function (pc, &name, NULL, NULL);
+ return (nbsd_pc_in_sigtramp (pc, name)
+ || i386nbsd_sigtramp_offset (next_frame) >= 0);
+}
-static struct core_fns i386nbsd_elfcore_fns =
+/* From <machine/signal.h>. */
+int i386nbsd_sc_reg_offset[] =
{
- bfd_target_elf_flavour, /* core_flavour */
- default_check_format, /* check_format */
- default_core_sniffer, /* core_sniffer */
- fetch_elfcore_registers, /* core_read_registers */
- NULL /* next */
+ 10 * 4, /* %eax */
+ 9 * 4, /* %ecx */
+ 8 * 4, /* %edx */
+ 7 * 4, /* %ebx */
+ 14 * 4, /* %esp */
+ 6 * 4, /* %ebp */
+ 5 * 4, /* %esi */
+ 4 * 4, /* %edi */
+ 11 * 4, /* %eip */
+ 13 * 4, /* %eflags */
+ 12 * 4, /* %cs */
+ 15 * 4, /* %ss */
+ 3 * 4, /* %ds */
+ 2 * 4, /* %es */
+ 1 * 4, /* %fs */
+ 0 * 4 /* %gs */
};
+static void
+i386nbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ /* Obviously NetBSD is BSD-based. */
+ i386bsd_init_abi (info, gdbarch);
+
+ /* NetBSD has a different `struct reg'. */
+ tdep->gregset_reg_offset = i386nbsd_r_reg_offset;
+ tdep->gregset_num_regs = ARRAY_SIZE (i386nbsd_r_reg_offset);
+ tdep->sizeof_gregset = 16 * 4;
+
+ /* NetBSD has different signal trampoline conventions. */
+ tdep->sigtramp_start = 0;
+ tdep->sigtramp_end = 0;
+ tdep->sigtramp_p = i386nbsd_sigtramp_p;
+
+ /* NetBSD uses -freg-struct-return by default. */
+ tdep->struct_return = reg_struct_return;
+
+ /* NetBSD has a `struct sigcontext' that's different from the
+ original 4.3 BSD. */
+ tdep->sc_reg_offset = i386nbsd_sc_reg_offset;
+ tdep->sc_num_regs = ARRAY_SIZE (i386nbsd_sc_reg_offset);
+}
+
+/* NetBSD a.out. */
+
+static void
+i386nbsdaout_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ i386nbsd_init_abi (info, gdbarch);
+
+ /* NetBSD a.out has a single register set. */
+ set_gdbarch_regset_from_core_section
+ (gdbarch, i386nbsd_aout_regset_from_core_section);
+}
+
+/* NetBSD ELF. */
+
+static void
+i386nbsdelf_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ /* It's still NetBSD. */
+ i386nbsd_init_abi (info, gdbarch);
+
+ /* But ELF-based. */
+ i386_elf_init_abi (info, gdbarch);
+
+ /* NetBSD ELF uses SVR4-style shared libraries. */
+ set_gdbarch_in_solib_call_trampoline
+ (gdbarch, generic_in_solib_call_trampoline);
+ set_solib_svr4_fetch_link_map_offsets
+ (gdbarch, svr4_ilp32_fetch_link_map_offsets);
+
+ /* NetBSD ELF uses -fpcc-struct-return by default. */
+ tdep->struct_return = pcc_struct_return;
+}
+
void
_initialize_i386nbsd_tdep (void)
{
- add_core_fns (&i386nbsd_core_fns);
- add_core_fns (&i386nbsd_elfcore_fns);
+ gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_NETBSD_AOUT,
+ i386nbsdaout_init_abi);
+ gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_NETBSD_ELF,
+ i386nbsdelf_init_abi);
}