diff options
Diffstat (limited to 'contrib/gdb/gdb/alphanbsd-tdep.c')
-rw-r--r-- | contrib/gdb/gdb/alphanbsd-tdep.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/contrib/gdb/gdb/alphanbsd-tdep.c b/contrib/gdb/gdb/alphanbsd-tdep.c new file mode 100644 index 0000000..28d1bb5 --- /dev/null +++ b/contrib/gdb/gdb/alphanbsd-tdep.c @@ -0,0 +1,234 @@ +/* Target-dependent code for NetBSD/Alpha. + + Copyright 2002, 2003, 2004 Free Software Foundation, Inc. + Contributed by Wasabi Systems, 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 "gdbcore.h" +#include "frame.h" +#include "regcache.h" +#include "value.h" +#include "osabi.h" + +#include "solib-svr4.h" + +#include "alpha-tdep.h" +#include "alphabsd-tdep.h" +#include "nbsd-tdep.h" + +static void +fetch_core_registers (char *core_reg_sect, unsigned core_reg_size, int which, + CORE_ADDR ignore) +{ + char *regs, *fpregs; + int regno; + + /* Table to map a gdb register number to a trapframe register index. */ + static const int regmap[] = + { + 0, 1, 2, 3, + 4, 5, 6, 7, + 8, 9, 10, 11, + 12, 13, 14, 15, + 30, 31, 32, 16, + 17, 18, 19, 20, + 21, 22, 23, 24, + 25, 29, 26 + }; +#define SIZEOF_TRAPFRAME (33 * 8) + + /* We get everything from one section. */ + if (which != 0) + return; + + regs = core_reg_sect; + fpregs = core_reg_sect + SIZEOF_TRAPFRAME; + + if (core_reg_size < (SIZEOF_TRAPFRAME + SIZEOF_STRUCT_FPREG)) + { + warning ("Wrong size register set in core file."); + return; + } + + /* Integer registers. */ + for (regno = 0; regno < ALPHA_ZERO_REGNUM; regno++) + supply_register (regno, regs + (regmap[regno] * 8)); + supply_register (ALPHA_ZERO_REGNUM, NULL); + supply_register (PC_REGNUM, regs + (28 * 8)); + + /* Floating point registers. */ + alphabsd_supply_fpreg (fpregs, -1); +} + +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 + alphabsd_supply_reg (core_reg_sect, -1); + break; + + case 2: /* Floating point registers. */ + if (core_reg_size != SIZEOF_STRUCT_FPREG) + warning ("Wrong size FP register set in core file."); + else + alphabsd_supply_fpreg (core_reg_sect, -1); + break; + + default: + /* Don't know what kind of register request this is; just ignore it. */ + break; + } +} + +static struct core_fns alphanbsd_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 alphanbsd_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/alpha, 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: + + ldq a0, 0(sp) + lda sp, 16(sp) + lda v0, 295(zero) # __sigreturn14 + call_pal callsys + + 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. */ +static const unsigned char sigtramp_retcode[] = +{ + 0x00, 0x00, 0x1e, 0xa6, /* ldq a0, 0(sp) */ + 0x10, 0x00, 0xde, 0x23, /* lda sp, 16(sp) */ + 0x27, 0x01, 0x1f, 0x20, /* lda v0, 295(zero) */ + 0x83, 0x00, 0x00, 0x00, /* call_pal callsys */ +}; +#define RETCODE_NWORDS 4 +#define RETCODE_SIZE (RETCODE_NWORDS * 4) + +LONGEST +alphanbsd_sigtramp_offset (CORE_ADDR pc) +{ + unsigned char ret[RETCODE_SIZE], w[4]; + LONGEST off; + int i; + + if (read_memory_nobpt (pc, (char *) w, 4) != 0) + return -1; + + for (i = 0; i < RETCODE_NWORDS; i++) + { + if (memcmp (w, sigtramp_retcode + (i * 4), 4) == 0) + break; + } + if (i == RETCODE_NWORDS) + return (-1); + + off = i * 4; + pc -= off; + + if (read_memory_nobpt (pc, (char *) ret, sizeof (ret)) != 0) + return -1; + + if (memcmp (ret, sigtramp_retcode, RETCODE_SIZE) == 0) + return off; + + return -1; +} + +static int +alphanbsd_pc_in_sigtramp (CORE_ADDR pc, char *func_name) +{ + return (nbsd_pc_in_sigtramp (pc, func_name) + || alphanbsd_sigtramp_offset (pc) >= 0); +} + +static CORE_ADDR +alphanbsd_sigcontext_addr (struct frame_info *frame) +{ + /* FIXME: This is not correct for all versions of NetBSD/alpha. + We will probably need to disassemble the trampoline to figure + out which trampoline frame type we have. */ + return get_frame_base (frame); +} + +static void +alphanbsd_init_abi (struct gdbarch_info info, + struct gdbarch *gdbarch) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); + + /* Hook into the DWARF CFI frame unwinder. */ + alpha_dwarf2_init_abi (info, gdbarch); + + /* Hook into the MDEBUG frame unwinder. */ + alpha_mdebug_init_abi (info, gdbarch); + + set_gdbarch_pc_in_sigtramp (gdbarch, alphanbsd_pc_in_sigtramp); + + /* NetBSD/alpha does not provide single step support via ptrace(2); we + must use software single-stepping. */ + set_gdbarch_software_single_step (gdbarch, alpha_software_single_step); + + set_solib_svr4_fetch_link_map_offsets (gdbarch, + nbsd_lp64_solib_svr4_fetch_link_map_offsets); + + tdep->dynamic_sigtramp_offset = alphanbsd_sigtramp_offset; + tdep->sigcontext_addr = alphanbsd_sigcontext_addr; + + tdep->jb_pc = 2; + tdep->jb_elt_size = 8; +} + +void +_initialize_alphanbsd_tdep (void) +{ + gdbarch_register_osabi (bfd_arch_alpha, 0, GDB_OSABI_NETBSD_ELF, + alphanbsd_init_abi); + gdbarch_register_osabi (bfd_arch_alpha, 0, GDB_OSABI_OPENBSD_ELF, + alphanbsd_init_abi); + + add_core_fns (&alphanbsd_core_fns); + add_core_fns (&alphanbsd_elfcore_fns); +} |