-/* Target-dependent code for NetBSD/i386, for GDB.
- Copyright 1988, 1989, 1991, 1992, 1994, 1996, 2000
+/* 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"
-#if 0
-#include <sys/types.h>
-#include <sys/ptrace.h>
-#include <machine/reg.h>
-#include <machine/frame.h>
-#include "inferior.h"
-#include "gdbcore.h" /* for registers_fetched() */
-#endif
-
-int
-i386nbsd_use_struct_convention (int gcc_p, struct type *type)
-{
- return !(TYPE_LENGTH (type) == 1
- || TYPE_LENGTH (type) == 2
- || TYPE_LENGTH (type) == 4
- || TYPE_LENGTH (type) == 8);
+#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"
+
+/* 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, /* %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 */
+};
+
+static void
+i386nbsd_aout_supply_regset (const struct regset *regset,
+ struct regcache *regcache, int regnum,
+ const void *regs, size_t len)
+{
+ const struct gdbarch_tdep *tdep = gdbarch_tdep (regset->arch);
+
+ 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 const struct regset *
+i386nbsd_aout_regset_from_core_section (struct gdbarch *gdbarch,
+ const char *sect_name,
+ size_t sect_size)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ /* NetBSD a.out core dumps don't use seperate register sets for the
+ general-purpose and floating-point registers. */
+
+ if (strcmp (sect_name, ".reg") == 0
+ && sect_size >= tdep->sizeof_gregset + I387_SIZEOF_FSAVE)
+ {
+ if (tdep->gregset == NULL)
+ tdep->gregset =
+ regset_alloc (gdbarch, i386nbsd_aout_supply_regset, NULL);
+ return tdep->gregset;
+ }
+
+ 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:
+
+ leal 0x10(%esp), %eax
+ pushl %eax
+ pushl %eax
+ movl $0x127, %eax # __sigreturn14
+ int $0x80
+
+ 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
+
+#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)
+{
+ 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 RETCODE_INSN1:
+ off = 0;
+ break;
+
+ 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
+ off = RETCODE_INSN3_OFF;
+ break;
+
+ case RETCODE_INSN4:
+ off = RETCODE_INSN4_OFF;
+ break;
+
+ 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;
+}
+
+/* Return whether the frame preceding NEXT_FRAME corresponds to a
+ NetBSD sigtramp routine. */
+
+static int
+i386nbsd_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 (nbsd_pc_in_sigtramp (pc, name)
+ || i386nbsd_sigtramp_offset (next_frame) >= 0);
+}
+
+/* From <machine/signal.h>. */
+int i386nbsd_sc_reg_offset[] =
+{
+ 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_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)
+{
+ 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);
}
projects / deliverable / binutils-gdb.git / blobdiff