From c5a27d9ca51b32accd04503e79c8dd01fc47eed2 Mon Sep 17 00:00:00 2001 From: Jeff Johnston Date: Wed, 8 Jun 2005 21:54:23 +0000 Subject: 2005-06-08 Jeff Johnston David Mosberger * ia64-tdep.c (KERNEL_START): New macro. (ia64_pseudo_register_read): Fix code to use libunwind to properly get the rse registers. (ia64_frame_this_id): Mark outermost frame with null frame id. (ia64_sigtramp_frame_prev_register): Fix up debug output. (ia64_access_rse_reg): New accessor function. (ia64_access_mem): Add special logic for accessing the kernel's unwind table. (getunwind_table): Fix for corefiles. (get_kernel_table): Fix to handle vDSO. (ia64_libunwind_frame_this_id): Check for null frame id and don't unwind past pc value of 0. Fix debugging output. (ia64_libunwind_sigtramp_frame_this_id): New function. (ia64_libunwind_sigtramp_frame_prev_register): Ditto. (ia64_libunwind_sigtramp_frame_sniffer): Ditto. (ia64_libunwind_sigtramp_frame_unwind): New unwinder. (ia64_unw_rse_accessors): New libunwind accessors. (ia64_libunwind_descr): Add ia64_unw_rse_accessors. (ia64_gdbarch_init)[HAVE_LIBUNWIND_IA64_H]: Use ia64_libunwind_sigtramp_frame_sniffer instead of ia64_sigtramp_frame_sniffer. * libunwind-frame.c (libunwind_frame_set_descr): Add special register accessors. (libunwind_frame_cache): Add special logic to check for 0 pc value. Check for a signal trampoline frame. (libunwind_frame_this_id): Check if libunwind_frame_cache returns NULL. (libunwind_frame_prev_register): Check for NULL cache. (libunwind_frame_base_address): Ditto. (libunwind_sigtramp_frame_sniffer): New function. (libunwind_get_reg_special): Ditto. (libunwind_load): Add unw_is_signal_frame support. * libunwind-frame.h (struct libunwind_descr): Add special_accessors field. (libunwind_sigtramp_frame_sniffer): New prototype. (libunwind_get_reg_special): Ditto. --- gdb/libunwind-frame.c | 123 ++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 119 insertions(+), 4 deletions(-) (limited to 'gdb/libunwind-frame.c') diff --git a/gdb/libunwind-frame.c b/gdb/libunwind-frame.c index 4e5d6b5..9f5a31e 100644 --- a/gdb/libunwind-frame.c +++ b/gdb/libunwind-frame.c @@ -49,6 +49,7 @@ static struct gdbarch_data *libunwind_descr_handle; 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_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); @@ -78,6 +79,7 @@ struct libunwind_frame_cache static char *get_reg_name = STRINGIFY(UNW_OBJ(get_reg)); static char *get_fpreg_name = STRINGIFY(UNW_OBJ(get_fpreg)); static char *get_saveloc_name = STRINGIFY(UNW_OBJ(get_save_loc)); +static char *is_signal_frame_name = STRINGIFY(UNW_OBJ(is_signal_frame)); static char *step_name = STRINGIFY(UNW_OBJ(step)); static char *init_remote_name = STRINGIFY(UNW_OBJ(init_remote)); static char *create_addr_space_name = STRINGIFY(UNW_OBJ(create_addr_space)); @@ -119,6 +121,7 @@ libunwind_frame_set_descr (struct gdbarch *gdbarch, struct libunwind_descr *desc arch_descr->uw2gdb = descr->uw2gdb; arch_descr->is_fpreg = descr->is_fpreg; arch_descr->accessors = descr->accessors; + arch_descr->special_accessors = descr->special_accessors; } static struct libunwind_frame_cache * @@ -139,6 +142,10 @@ libunwind_frame_cache (struct frame_info *next_frame, void **this_cache) cache = FRAME_OBSTACK_ZALLOC (struct libunwind_frame_cache); cache->func_addr = frame_func_unwind (next_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 @@ -156,7 +163,8 @@ libunwind_frame_cache (struct frame_info *next_frame, void **this_cache) : __LITTLE_ENDIAN); unw_init_remote_p (&cache->cursor, as, next_frame); - unw_step_p (&cache->cursor); + if (unw_step_p (&cache->cursor) < 0) + return NULL; /* To get base address, get sp from previous frame. */ uw_sp_regnum = descr->gdb2uw (SP_REGNUM); @@ -208,8 +216,14 @@ libunwind_frame_sniffer (struct frame_info *next_frame) ret = unw_init_remote_p (&cursor, as, next_frame); - if (ret >= 0) - ret = unw_step_p (&cursor); + if (ret < 0) + return NULL; + + + /* Check to see if we have libunwind info by checking if we are in a + signal frame. If it doesn't return an error, we have libunwind info + and can use libunwind. */ + ret = unw_is_signal_frame_p (&cursor); if (ret < 0) return NULL; @@ -224,7 +238,10 @@ libunwind_frame_this_id (struct frame_info *next_frame, void **this_cache, struct libunwind_frame_cache *cache = libunwind_frame_cache (next_frame, this_cache); - (*this_id) = frame_id_build (cache->base, cache->func_addr); + if (cache != NULL) + (*this_id) = frame_id_build (cache->base, cache->func_addr); + else + (*this_id) = null_frame_id; } void @@ -245,6 +262,9 @@ libunwind_frame_prev_register (struct frame_info *next_frame, void **this_cache, unw_regnum_t uw_regnum; struct libunwind_descr *descr; + if (cache == NULL) + return; + /* Convert from gdb register number to libunwind register number. */ descr = libunwind_descr (get_frame_arch (next_frame)); uw_regnum = descr->gdb2uw (regnum); @@ -312,6 +332,8 @@ libunwind_frame_base_address (struct frame_info *next_frame, void **this_cache) struct libunwind_frame_cache *cache = libunwind_frame_cache (next_frame, this_cache); + if (cache == NULL) + return (CORE_ADDR)NULL; return cache->base; } @@ -325,6 +347,95 @@ libunwind_search_unwind_table (void *as, long ip, void *di, di, pi, need_unwind_info, args); } +/* 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) +{ + unw_cursor_t cursor; + unw_accessors_t *acc; + unw_addr_space_t as; + struct libunwind_descr *descr; + 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. */ + + descr = libunwind_descr (get_frame_arch (next_frame)); + acc = descr->accessors; + as = unw_create_addr_space_p (acc, + TARGET_BYTE_ORDER == BFD_ENDIAN_BIG + ? __BIG_ENDIAN + : __LITTLE_ENDIAN); + + ret = unw_init_remote_p (&cursor, as, next_frame); + + if (ret < 0) + return NULL; + + /* Check to see if we are in a signal frame. */ + ret = unw_is_signal_frame_p (&cursor); + if (ret > 0) + return &libunwind_frame_unwind; + + return NULL; +} + +/* The following routine is for accessing special registers of the top frame. + A special set of accessors must be given that work without frame info. + This is used by ia64 to access the rse registers r32-r127. While they + are usually located at BOF, this is not always true and only the libunwind + info can decipher where they actually are. */ +int +libunwind_get_reg_special (struct gdbarch *gdbarch, int regnum, void *buf) +{ + unw_cursor_t cursor; + unw_accessors_t *acc; + unw_addr_space_t as; + struct libunwind_descr *descr; + int ret; + unw_regnum_t uw_regnum; + unw_word_t intval; + unw_fpreg_t fpval; + void *ptr; + + + descr = libunwind_descr (gdbarch); + acc = descr->special_accessors; + as = unw_create_addr_space_p (acc, + TARGET_BYTE_ORDER == BFD_ENDIAN_BIG + ? __BIG_ENDIAN + : __LITTLE_ENDIAN); + + ret = unw_init_remote_p (&cursor, as, NULL); + if (ret < 0) + return -1; + + uw_regnum = descr->gdb2uw (regnum); + + if (descr->is_fpreg (uw_regnum)) + { + ret = unw_get_fpreg_p (&cursor, uw_regnum, &fpval); + ptr = &fpval; + } + else + { + ret = unw_get_reg_p (&cursor, uw_regnum, &intval); + ptr = &intval; + } + + if (ret < 0) + return -1; + + if (buf) + memcpy (buf, ptr, register_size (current_gdbarch, regnum)); + + return 0; +} + static int libunwind_load (void) { @@ -348,6 +459,10 @@ libunwind_load (void) if (unw_get_saveloc_p == NULL) return 0; + unw_is_signal_frame_p = dlsym (handle, is_signal_frame_name); + if (unw_is_signal_frame_p == NULL) + return 0; + unw_step_p = dlsym (handle, step_name); if (unw_step_p == NULL) return 0; -- cgit v1.1