/* Frame unwinder for frames using the libunwind library.
- Copyright (C) 2003, 2004, 2006, 2007 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011
+ Free Software Foundation, Inc.
Written by Jeff Johnston, contributed by Red Hat Inc.
#include "complaints.h"
+/* The following two macros are normally defined in <endian.h>.
+ But systems such as ia64-hpux do not provide such header, so
+ we just define them here if not already defined. */
+#ifndef __LITTLE_ENDIAN
+#define __LITTLE_ENDIAN 1234
+#endif
+#ifndef __BIG_ENDIAN
+#define __BIG_ENDIAN 4321
+#endif
+
static int libunwind_initialized;
static struct gdbarch_data *libunwind_descr_handle;
/* Required function pointers from libunwind. */
static int (*unw_get_reg_p) (unw_cursor_t *, unw_regnum_t, unw_word_t *);
static int (*unw_get_fpreg_p) (unw_cursor_t *, unw_regnum_t, unw_fpreg_t *);
-static int (*unw_get_saveloc_p) (unw_cursor_t *, unw_regnum_t, unw_save_loc_t *);
+static int (*unw_get_saveloc_p) (unw_cursor_t *, unw_regnum_t,
+ unw_save_loc_t *);
static int (*unw_is_signal_frame_p) (unw_cursor_t *);
static int (*unw_step_p) (unw_cursor_t *);
static int (*unw_init_remote_p) (unw_cursor_t *, unw_addr_space_t, void *);
static unw_addr_space_t (*unw_create_addr_space_p) (unw_accessors_t *, int);
static void (*unw_destroy_addr_space_p) (unw_addr_space_t);
-static int (*unw_search_unwind_table_p) (unw_addr_space_t, unw_word_t, unw_dyn_info_t *,
+static int (*unw_search_unwind_table_p) (unw_addr_space_t, unw_word_t,
+ unw_dyn_info_t *,
unw_proc_info_t *, int, void *);
static unw_word_t (*unw_find_dyn_list_p) (unw_addr_space_t, unw_dyn_info_t *,
void *);
unw_addr_space_t as;
};
-/* We need to qualify the function names with a platform-specific prefix to match
- the names used by the libunwind library. The UNW_OBJ macro is provided by the
- libunwind.h header file. */
+/* We need to qualify the function names with a platform-specific prefix
+ to match the names used by the libunwind library. The UNW_OBJ macro is
+ provided by the libunwind.h header file. */
#define STRINGIFY2(name) #name
#define STRINGIFY(name) STRINGIFY2(name)
static char *init_remote_name = STRINGIFY(UNW_OBJ(init_remote));
static char *create_addr_space_name = STRINGIFY(UNW_OBJ(create_addr_space));
static char *destroy_addr_space_name = STRINGIFY(UNW_OBJ(destroy_addr_space));
-static char *search_unwind_table_name = STRINGIFY(UNW_OBJ(search_unwind_table));
+static char *search_unwind_table_name
+ = STRINGIFY(UNW_OBJ(search_unwind_table));
static char *find_dyn_list_name = STRINGIFY(UNW_OBJ(find_dyn_list));
static struct libunwind_descr *
static void *
libunwind_descr_init (struct gdbarch *gdbarch)
{
- struct libunwind_descr *descr = GDBARCH_OBSTACK_ZALLOC (gdbarch,
- struct libunwind_descr);
+ struct libunwind_descr *descr
+ = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct libunwind_descr);
+
return descr;
}
void
-libunwind_frame_set_descr (struct gdbarch *gdbarch, struct libunwind_descr *descr)
+libunwind_frame_set_descr (struct gdbarch *gdbarch,
+ struct libunwind_descr *descr)
{
struct libunwind_descr *arch_descr;
{
/* First time here. Must initialize data area. */
arch_descr = libunwind_descr_init (gdbarch);
- deprecated_set_gdbarch_data (gdbarch, libunwind_descr_handle, arch_descr);
+ deprecated_set_gdbarch_data (gdbarch,
+ libunwind_descr_handle, arch_descr);
}
/* Copy new descriptor info into arch descriptor. */
}
static struct libunwind_frame_cache *
-libunwind_frame_cache (struct frame_info *next_frame, void **this_cache)
+libunwind_frame_cache (struct frame_info *this_frame, void **this_cache)
{
unw_accessors_t *acc;
unw_addr_space_t as;
unw_regnum_t uw_sp_regnum;
struct libunwind_frame_cache *cache;
struct libunwind_descr *descr;
- struct gdbarch *gdbarch = get_frame_arch (next_frame);
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
int i, ret;
if (*this_cache)
/* Allocate a new cache. */
cache = FRAME_OBSTACK_ZALLOC (struct libunwind_frame_cache);
- /* We can assume we are unwinding a normal frame. Even if this is
- for a signal trampoline, ia64 signal "trampolines" use a normal
- subroutine call to start the signal handler. */
- cache->func_addr = frame_func_unwind (next_frame, NORMAL_FRAME);
- if (cache->func_addr == 0
- && frame_relative_level (next_frame) > 0
- && get_frame_type (next_frame) != SIGTRAMP_FRAME)
- return NULL;
-
- /* Get a libunwind cursor to the previous frame. We do this by initializing
- a cursor. Libunwind treats a new cursor as the top of stack and will get
- the current register set via the libunwind register accessor. Now, we
- provide the platform-specific accessors and we set up the register accessor to use
- the frame register unwinding interfaces so that we properly get the registers for
- the current frame rather than the top. We then use the unw_step function to
- move the libunwind cursor back one frame. We can later use this cursor to find previous
- registers via the unw_get_reg interface which will invoke libunwind's special logic. */
+ cache->func_addr = get_frame_func (this_frame);
+ if (cache->func_addr == 0)
+ /* This can happen when the frame corresponds to a function for which
+ there is no debugging information nor any entry in the symbol table.
+ This is probably a static function for which an entry in the symbol
+ table was not created when the objfile got linked (observed in
+ libpthread.so on ia64-hpux).
+
+ The best we can do, in that case, is use the frame PC as the function
+ address. We don't need to give up since we still have the unwind
+ record to help us perform the unwinding. There is also another
+ compelling to continue, because abandonning now means stopping
+ the backtrace, which can never be helpful for the user. */
+ cache->func_addr = get_frame_pc (this_frame);
+
+ /* Get a libunwind cursor to the previous frame.
+
+ We do this by initializing a cursor. Libunwind treats a new cursor
+ as the top of stack and will get the current register set via the
+ libunwind register accessor. Now, we provide the platform-specific
+ accessors and we set up the register accessor to use the frame
+ register unwinding interfaces so that we properly get the registers
+ for the current frame rather than the top. We then use the unw_step
+ function to move the libunwind cursor back one frame. We can later
+ use this cursor to find previous registers via the unw_get_reg
+ interface which will invoke libunwind's special logic. */
descr = libunwind_descr (gdbarch);
acc = descr->accessors;
as = unw_create_addr_space_p (acc,
? __BIG_ENDIAN
: __LITTLE_ENDIAN);
- unw_init_remote_p (&cache->cursor, as, next_frame);
+ unw_init_remote_p (&cache->cursor, as, this_frame);
if (unw_step_p (&cache->cursor) < 0)
{
unw_destroy_addr_space_p (as);
libunwind_frame_dealloc_cache (struct frame_info *self, void *this_cache)
{
struct libunwind_frame_cache *cache = this_cache;
+
if (cache->as)
unw_destroy_addr_space_p (cache->as);
}
static const struct frame_unwind libunwind_frame_unwind =
{
NORMAL_FRAME,
+ default_frame_unwind_stop_reason,
libunwind_frame_this_id,
libunwind_frame_prev_register,
NULL,
- NULL,
- NULL,
- libunwind_frame_dealloc_cache
+ libunwind_frame_sniffer,
+ libunwind_frame_dealloc_cache,
};
/* Verify if there is sufficient libunwind information for the frame to use
libunwind frame unwinding. */
-const struct frame_unwind *
-libunwind_frame_sniffer (struct frame_info *next_frame)
+int
+libunwind_frame_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame, void **this_cache)
{
unw_cursor_t cursor;
unw_accessors_t *acc;
unw_addr_space_t as;
struct libunwind_descr *descr;
- struct gdbarch *gdbarch = get_frame_arch (next_frame);
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
int i, ret;
- /* To test for libunwind unwind support, initialize a cursor to the current frame and try to back
- up. We use this same method when setting up the frame cache (see libunwind_frame_cache()).
- If libunwind returns success for this operation, it means that it has found sufficient
- libunwind unwinding information to do so. */
+ /* To test for libunwind unwind support, initialize a cursor to
+ the current frame and try to back up. We use this same method
+ when setting up the frame cache (see libunwind_frame_cache()).
+ If libunwind returns success for this operation, it means that
+ it has found sufficient libunwind unwinding information to do so. */
descr = libunwind_descr (gdbarch);
acc = descr->accessors;
? __BIG_ENDIAN
: __LITTLE_ENDIAN);
- ret = unw_init_remote_p (&cursor, as, next_frame);
+ ret = unw_init_remote_p (&cursor, as, this_frame);
if (ret < 0)
{
unw_destroy_addr_space_p (as);
- return NULL;
+ return 0;
}
unw_destroy_addr_space_p (as);
if (ret < 0)
- return NULL;
+ return 0;
- return &libunwind_frame_unwind;
+ return 1;
}
void
-libunwind_frame_this_id (struct frame_info *next_frame, void **this_cache,
- struct frame_id *this_id)
+libunwind_frame_this_id (struct frame_info *this_frame, void **this_cache,
+ struct frame_id *this_id)
{
struct libunwind_frame_cache *cache =
- libunwind_frame_cache (next_frame, this_cache);
+ libunwind_frame_cache (this_frame, this_cache);
if (cache != NULL)
(*this_id) = frame_id_build (cache->base, cache->func_addr);
- else
- (*this_id) = null_frame_id;
}
-void
-libunwind_frame_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 value *
+libunwind_frame_prev_register (struct frame_info *this_frame,
+ void **this_cache, int regnum)
{
struct libunwind_frame_cache *cache =
- libunwind_frame_cache (next_frame, this_cache);
- struct gdbarch *gdbarch = get_frame_arch (next_frame);
+ libunwind_frame_cache (this_frame, this_cache);
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
void *ptr;
unw_cursor_t *c;
unw_fpreg_t fpval;
unw_regnum_t uw_regnum;
struct libunwind_descr *descr;
+ struct value *val = NULL;
if (cache == NULL)
- return;
+ return frame_unwind_got_constant (this_frame, regnum, 0);
/* Convert from gdb register number to libunwind register number. */
- descr = libunwind_descr (get_frame_arch (next_frame));
+ descr = libunwind_descr (get_frame_arch (this_frame));
uw_regnum = descr->gdb2uw (regnum);
gdb_assert (regnum >= 0);
if (!target_has_registers)
error (_("No registers."));
- *optimizedp = 0;
- *addrp = 0;
- *lvalp = not_lval;
- *realnump = -1;
-
- if (valuep)
- memset (valuep, 0, register_size (gdbarch, regnum));
-
if (uw_regnum < 0)
- return;
-
- /* To get the previous register, we use the libunwind register APIs with
- the cursor we have already pushed back to the previous frame. */
-
- if (descr->is_fpreg (uw_regnum))
- {
- ret = unw_get_fpreg_p (&cache->cursor, uw_regnum, &fpval);
- ptr = &fpval;
- }
- else
- {
- ret = unw_get_reg_p (&cache->cursor, uw_regnum, &intval);
- ptr = &intval;
- }
-
- if (ret < 0)
- return;
-
- if (valuep)
- memcpy (valuep, ptr, register_size (gdbarch, regnum));
+ return frame_unwind_got_constant (this_frame, regnum, 0);
if (unw_get_saveloc_p (&cache->cursor, uw_regnum, &sl) < 0)
- return;
+ return frame_unwind_got_constant (this_frame, regnum, 0);
switch (sl.type)
{
- case UNW_SLT_NONE:
- *optimizedp = 1;
- break;
-
case UNW_SLT_MEMORY:
- *lvalp = lval_memory;
- *addrp = sl.u.addr;
+ val = frame_unwind_got_memory (this_frame, regnum, sl.u.addr);
break;
case UNW_SLT_REG:
- *lvalp = lval_register;
- *realnump = regnum;
+ val = frame_unwind_got_register (this_frame, regnum,
+ descr->uw2gdb (sl.u.regnum));
break;
+ case UNW_SLT_NONE:
+ {
+ /* The register is not stored at a specific memory address nor
+ inside another register. So use libunwind to fetch the register
+ value for us, and create a constant value with the result. */
+ if (descr->is_fpreg (uw_regnum))
+ {
+ ret = unw_get_fpreg_p (&cache->cursor, uw_regnum, &fpval);
+ if (ret < 0)
+ return frame_unwind_got_constant (this_frame, regnum, 0);
+ val = frame_unwind_got_bytes (this_frame, regnum,
+ (gdb_byte *) &fpval);
+ }
+ else
+ {
+ ret = unw_get_reg_p (&cache->cursor, uw_regnum, &intval);
+ if (ret < 0)
+ return frame_unwind_got_constant (this_frame, regnum, 0);
+ val = frame_unwind_got_constant (this_frame, regnum, intval);
+ }
+ break;
+ }
}
+
+ return val;
}
CORE_ADDR
-libunwind_frame_base_address (struct frame_info *next_frame, void **this_cache)
+libunwind_frame_base_address (struct frame_info *this_frame, void **this_cache)
{
struct libunwind_frame_cache *cache =
- libunwind_frame_cache (next_frame, this_cache);
+ libunwind_frame_cache (this_frame, this_cache);
if (cache == NULL)
return (CORE_ADDR)NULL;
}
/* Verify if we are in a sigtramp frame and we can use libunwind to unwind. */
-const struct frame_unwind *
-libunwind_sigtramp_frame_sniffer (struct frame_info *next_frame)
+int
+libunwind_sigtramp_frame_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame,
+ void **this_cache)
{
unw_cursor_t cursor;
unw_accessors_t *acc;
unw_addr_space_t as;
struct libunwind_descr *descr;
- struct gdbarch *gdbarch = get_frame_arch (next_frame);
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
int i, ret;
/* To test for libunwind unwind support, initialize a cursor to the
? __BIG_ENDIAN
: __LITTLE_ENDIAN);
- ret = unw_init_remote_p (&cursor, as, next_frame);
+ ret = unw_init_remote_p (&cursor, as, this_frame);
if (ret < 0)
{
unw_destroy_addr_space_p (as);
- return NULL;
+ return 0;
}
/* Check to see if we are in a signal frame. */
ret = unw_is_signal_frame_p (&cursor);
unw_destroy_addr_space_p (as);
if (ret > 0)
- return &libunwind_frame_unwind;
+ return 1;
- return NULL;
+ return 0;
}
/* The following routine is for accessing special registers of the top frame.
void
_initialize_libunwind_frame (void)
{
- libunwind_descr_handle = gdbarch_data_register_post_init (libunwind_descr_init);
+ libunwind_descr_handle
+ = gdbarch_data_register_post_init (libunwind_descr_init);
libunwind_initialized = libunwind_load ();
}