diff options
Diffstat (limited to 'gdb/sparcobsd-tdep.c')
-rw-r--r-- | gdb/sparcobsd-tdep.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/gdb/sparcobsd-tdep.c b/gdb/sparcobsd-tdep.c new file mode 100644 index 00000000000..108e255ed13 --- /dev/null +++ b/gdb/sparcobsd-tdep.c @@ -0,0 +1,171 @@ +/* Target-dependent code for OpenBSD/sparc. + + Copyright 2004 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 "floatformat.h" +#include "frame.h" +#include "frame-unwind.h" +#include "osabi.h" +#include "solib-svr4.h" +#include "symtab.h" +#include "trad-frame.h" + +#include "gdb_assert.h" + +#include "sparc-tdep.h" +#include "nbsd-tdep.h" + +/* Signal trampolines. */ + +/* The OpenBSD kernel maps the signal trampoline at some random + location in user space, which means that the traditional BSD way of + detecting it won't work. + + The signal trampoline will be mapped at an address that is page + aligned. We recognize the signal trampoline by the looking for the + sigreturn system call. */ + +static const int sparc32obsd_page_size = 4096; + +static int +sparc32obsd_pc_in_sigtramp (CORE_ADDR pc, char *name) +{ + CORE_ADDR start_pc = (pc & ~(sparc32obsd_page_size - 1)); + unsigned long insn; + + if (name) + return 0; + + /* Check for "restore %g0, SYS_sigreturn, %g1". */ + insn = sparc_fetch_instruction (start_pc + 0xec); + if (insn != 0x83e82067) + return 0; + + /* Check for "t ST_SYSCALL". */ + insn = sparc_fetch_instruction (start_pc + 0xf4); + if (insn != 0x91d02000) + return 0; + + return 1; +} + +static struct sparc_frame_cache * +sparc32obsd_frame_cache (struct frame_info *next_frame, void **this_cache) +{ + struct sparc_frame_cache *cache; + CORE_ADDR addr; + + if (*this_cache) + return *this_cache; + + cache = sparc_frame_cache (next_frame, this_cache); + gdb_assert (cache == *this_cache); + + /* If we couldn't find the frame's function, we're probably dealing + with an on-stack signal trampoline. */ + if (cache->pc == 0) + { + cache->pc = frame_pc_unwind (next_frame); + cache->pc &= ~(sparc32obsd_page_size - 1); + + /* Since we couldn't find the frame's function, the cache was + initialized under the assumption that we're frameless. */ + cache->frameless_p = 0; + addr = frame_unwind_register_unsigned (next_frame, SPARC_FP_REGNUM); + cache->base = addr; + } + + cache->saved_regs = sparc32nbsd_sigcontext_saved_regs (next_frame); + + return cache; +} + +static void +sparc32obsd_frame_this_id (struct frame_info *next_frame, void **this_cache, + struct frame_id *this_id) +{ + struct sparc_frame_cache *cache = + sparc32obsd_frame_cache (next_frame, this_cache); + + (*this_id) = frame_id_build (cache->base, cache->pc); +} + +static void +sparc32obsd_frame_prev_register (struct frame_info *next_frame, + void **this_cache, + int regnum, int *optimizedp, + enum lval_type *lvalp, CORE_ADDR *addrp, + int *realnump, void *valuep) +{ + struct sparc_frame_cache *cache = + sparc32obsd_frame_cache (next_frame, this_cache); + + trad_frame_prev_register (next_frame, cache->saved_regs, regnum, + optimizedp, lvalp, addrp, realnump, valuep); +} + +static const struct frame_unwind sparc32obsd_frame_unwind = +{ + SIGTRAMP_FRAME, + sparc32obsd_frame_this_id, + sparc32obsd_frame_prev_register +}; + +static const struct frame_unwind * +sparc32obsd_sigtramp_frame_sniffer (struct frame_info *next_frame) +{ + CORE_ADDR pc = frame_pc_unwind (next_frame); + char *name; + + find_pc_partial_function (pc, &name, NULL, NULL); + if (sparc32obsd_pc_in_sigtramp (pc, name)) + return &sparc32obsd_frame_unwind; + + return NULL; +} + + +static void +sparc32obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) +{ + struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); + + /* OpenBSD doesn't support the 128-bit `long double' from the psABI. */ + set_gdbarch_long_double_bit (gdbarch, 64); + set_gdbarch_long_double_format (gdbarch, &floatformat_ieee_double_big); + + set_gdbarch_pc_in_sigtramp (gdbarch, sparc32obsd_pc_in_sigtramp); + frame_unwind_append_sniffer (gdbarch, sparc32obsd_sigtramp_frame_sniffer); + + set_solib_svr4_fetch_link_map_offsets + (gdbarch, nbsd_ilp32_solib_svr4_fetch_link_map_offsets); +} + + +/* Provide a prototype to silence -Wmissing-prototypes. */ +void _initialize_sparc32obsd_tdep (void); + +void +_initialize_sparc32obsd_tdep (void) +{ + gdbarch_register_osabi (bfd_arch_sparc, 0, GDB_OSABI_OPENBSD_ELF, + sparc32obsd_init_abi); +} |