/* Target-dependent code for NetBSD/i386, for GDB. Copyright 1988, 1989, 1991, 1992, 1994, 1996, 2000, 2001, 2002, 2003 Free Software Foundation, Inc. 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 "gdbtypes.h" #include "gdbcore.h" #include "regcache.h" #include "arch-utils.h" #include "osabi.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[] = { ( 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 */ }; #define SIZEOF_STRUCT_REG (16 * 4) static void i386nbsd_supply_reg (char *regs, int regno) { int i; for (i = 0; i <= 15; i++) if (regno == i || regno == -1) supply_register (i, regs + regmap[i]); } static void fetch_core_registers (char *core_reg_sect, unsigned core_reg_size, int which, CORE_ADDR ignore) { char *regs, *fsave; /* We get everything from one section. */ if (which != 0) return; if (core_reg_size < (SIZEOF_STRUCT_REG + 108)) { warning ("Wrong size register set in core file."); return; } regs = core_reg_sect; fsave = core_reg_sect + SIZEOF_STRUCT_REG; /* Integer registers. */ i386nbsd_supply_reg (regs, -1); /* Floating point registers. */ i387_supply_fsave (fsave); } static void fetch_elfcore_registers (char *core_reg_sect, unsigned core_reg_size, int which, CORE_ADDR ignore) { switch (which) { 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); break; case 2: /* Floating point registers. */ if (core_reg_size != 108) warning ("Wrong size FP register set in core file."); else i387_supply_fsave (core_reg_sect); 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); break; default: /* Don't know what kind of register request this is; just ignore it. */ break; } } static struct core_fns i386nbsd_core_fns = { bfd_target_unknown_flavour, /* core_flavour */ default_check_format, /* check_format */ default_core_sniffer, /* core_sniffer */ fetch_core_registers, /* core_read_registers */ NULL /* next */ }; static struct core_fns i386nbsd_elfcore_fns = { bfd_target_elf_flavour, /* core_flavour */ default_check_format, /* check_format */ default_core_sniffer, /* core_sniffer */ fetch_elfcore_registers, /* core_read_registers */ NULL /* next */ }; /* 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 (CORE_ADDR pc) { unsigned char ret[sizeof(sigtramp_retcode)], insn; LONGEST off; int i; if (read_memory_nobpt (pc, &insn, 1) != 0) 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 (read_memory_nobpt (pc + 1, &insn, 1) != 0) 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 (read_memory_nobpt (pc, (char *) ret, sizeof (ret)) != 0) return -1; if (memcmp (ret, sigtramp_retcode, sizeof (ret)) == 0) return off; return -1; } static int i386nbsd_pc_in_sigtramp (CORE_ADDR pc, char *name) { return (nbsd_pc_in_sigtramp (pc, name) || i386nbsd_sigtramp_offset (pc) >= 0); } /* From . */ int i386nbsd_sc_pc_offset = 44; int i386nbsd_sc_sp_offset = 56; 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 different signal trampoline conventions. */ set_gdbarch_pc_in_sigtramp (gdbarch, i386nbsd_pc_in_sigtramp); /* FIXME: kettenis/20020906: We should probably provide NetBSD-specific versions of these functions if we want to recognize signal trampolines that live on the stack. */ set_gdbarch_sigtramp_start (gdbarch, NULL); set_gdbarch_sigtramp_end (gdbarch, NULL); /* NetBSD uses -freg-struct-return by default. */ tdep->struct_return = reg_struct_return; /* NetBSD has a `struct sigcontext' that's different from the origional 4.3 BSD. */ tdep->sc_pc_offset = i386nbsd_sc_pc_offset; tdep->sc_sp_offset = i386nbsd_sc_sp_offset; } /* 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, nbsd_ilp32_solib_svr4_fetch_link_map_offsets); /* NetBSD ELF uses -fpcc-struct-return by default. */ tdep->struct_return = pcc_struct_return; /* We support the SSE registers on NetBSD ELF. */ tdep->num_xmm_regs = I386_NUM_XREGS - 1; set_gdbarch_num_regs (gdbarch, I386_NUM_GREGS + I386_NUM_FREGS + I386_NUM_XREGS); } 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, i386nbsd_init_abi); gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_NETBSD_ELF, i386nbsdelf_init_abi); }