diff options
Diffstat (limited to 'gdb/i386obsd-tdep.c')
| -rw-r--r-- | gdb/i386obsd-tdep.c | 119 |
1 files changed, 118 insertions, 1 deletions
diff --git a/gdb/i386obsd-tdep.c b/gdb/i386obsd-tdep.c index f309244..ab38269 100644 --- a/gdb/i386obsd-tdep.c +++ b/gdb/i386obsd-tdep.c @@ -24,6 +24,7 @@ #include "defs.h" #include "arch-utils.h" #include "frame.h" +#include "frame-unwind.h" #include "gdbcore.h" #include "regcache.h" #include "regset.h" @@ -31,6 +32,7 @@ #include "objfiles.h" #include "osabi.h" #include "target.h" +#include "trad-frame.h" #include "gdb_assert.h" #include "gdb_string.h" @@ -265,7 +267,6 @@ i386obsd_supply_uthread (struct regcache *regcache, regcache_raw_supply (regcache, i, buf); } } - } static void @@ -313,6 +314,119 @@ i386obsd_collect_uthread (const struct regcache *regcache, } } } + +/* Kernel debugging support. */ + +/* From <machine/frame.h>. Note that %esp and %ess are only saved in + a trap frame when entering the kernel from user space. */ +static int i386obsd_tf_reg_offset[] = +{ + 10 * 4, /* %eax */ + 9 * 4, /* %ecx */ + 8 * 4, /* %edx */ + 7 * 4, /* %ebx */ + -1, /* %esp */ + 6 * 4, /* %ebp */ + 5 * 4, /* %esi */ + 4 * 4, /* %edi */ + 13 * 4, /* %eip */ + 15 * 4, /* %eflags */ + 14 * 4, /* %cs */ + -1, /* %ss */ + 3 * 4, /* %ds */ + 2 * 4, /* %es */ + 0 * 4, /* %fs */ + 1 * 4 /* %gs */ +}; + +static struct trad_frame_cache * +i386obsd_trapframe_cache(struct frame_info *next_frame, void **this_cache) +{ + struct trad_frame_cache *cache; + CORE_ADDR func, sp, addr; + ULONGEST cs; + int i; + + if (*this_cache) + return *this_cache; + + cache = trad_frame_cache_zalloc (next_frame); + *this_cache = cache; + + func = frame_func_unwind (next_frame); + sp = frame_unwind_register_unsigned (next_frame, I386_ESP_REGNUM); + for (i = 0; i < ARRAY_SIZE (i386obsd_tf_reg_offset); i++) + if (i386obsd_tf_reg_offset[i] != -1) + trad_frame_set_reg_addr (cache, i, sp + i386obsd_tf_reg_offset[i]); + + /* Read %cs from trap frame. */ + addr = sp + i386obsd_tf_reg_offset[I386_CS_REGNUM]; + cs = read_memory_unsigned_integer (addr, 4); + if ((cs & I386_SEL_RPL) == I386_SEL_UPL) + { + /* Trap from use space; terminate backtrace. */ + trad_frame_set_id (cache, null_frame_id); + } + else + { + /* Construct the frame ID using the function start. */ + trad_frame_set_id (cache, frame_id_build (sp + 8, func)); + } + + return cache; +} + +static void +i386obsd_trapframe_this_id (struct frame_info *next_frame, + void **this_cache, struct frame_id *this_id) +{ + struct trad_frame_cache *cache = + i386obsd_trapframe_cache (next_frame, this_cache); + + trad_frame_get_id (cache, this_id); +} + +static void +i386obsd_trapframe_prev_register (struct frame_info *next_frame, + void **this_cache, int regnum, + int *optimizedp, enum lval_type *lvalp, + CORE_ADDR *addrp, int *realnump, + gdb_byte *valuep) +{ + struct trad_frame_cache *cache = + i386obsd_trapframe_cache (next_frame, this_cache); + + trad_frame_get_register (cache, next_frame, regnum, + optimizedp, lvalp, addrp, realnump, valuep); +} + +static const struct frame_unwind i386obsd_trapframe_unwind = { + /* FIXME: kettenis/20051219: This really is more like an interrupt + frame, but SIGTRAMP_FRAME would print <signal handler called>, + which really is not what we want here. */ + NORMAL_FRAME, + i386obsd_trapframe_this_id, + i386obsd_trapframe_prev_register +}; + +static const struct frame_unwind * +i386obsd_trapframe_sniffer (struct frame_info *next_frame) +{ + ULONGEST cs; + char *name; + + cs = frame_unwind_register_unsigned (next_frame, I386_CS_REGNUM); + if ((cs & I386_SEL_RPL) == I386_SEL_UPL) + return NULL; + + find_pc_partial_function (frame_pc_unwind (next_frame), &name, NULL, NULL); + if (name && ((strcmp ("calltrap", name) == 0) + || (strcmp ("syscall1", name) == 0))) + return &i386obsd_trapframe_unwind; + + return NULL; +} + static void i386obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) @@ -343,6 +457,9 @@ i386obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) /* OpenBSD provides a user-level threads implementation. */ bsd_uthread_set_supply_uthread (gdbarch, i386obsd_supply_uthread); bsd_uthread_set_collect_uthread (gdbarch, i386obsd_collect_uthread); + + /* Unwind kernel trap frames correctly. */ + frame_unwind_append_sniffer (gdbarch, i386obsd_trapframe_sniffer); } /* OpenBSD a.out. */ |