2 * dwarf-aux.c : libdw auxiliary interfaces
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25 #include "dwarf-aux.h"
29 * cu_find_realpath - Find the realpath of the target file
30 * @cu_die: A DIE(dwarf information entry) of CU(compilation Unit)
31 * @fname: The tail filename of the target file
33 * Find the real(long) path of @fname in @cu_die.
35 const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname)
39 const char *src = NULL;
45 ret = dwarf_getsrcfiles(cu_die, &files, &nfiles);
49 for (i = 0; i < nfiles; i++) {
50 src = dwarf_filesrc(files, i, NULL, NULL);
51 if (strtailcmp(src, fname) == 0)
60 * cu_get_comp_dir - Get the path of compilation directory
63 * Get the path of compilation directory of given @cu_die.
64 * Since this depends on DW_AT_comp_dir, older gcc will not
65 * embedded it. In that case, this returns NULL.
67 const char *cu_get_comp_dir(Dwarf_Die *cu_die)
70 if (dwarf_attr(cu_die, DW_AT_comp_dir, &attr) == NULL)
72 return dwarf_formstring(&attr);
76 * cu_find_lineinfo - Get a line number and file name for given address
79 * @fname: a pointer which returns the file name string
80 * @lineno: a pointer which returns the line number
82 * Find a line number and file name for @addr in @cu_die.
84 int cu_find_lineinfo(Dwarf_Die *cu_die, unsigned long addr,
85 const char **fname, int *lineno)
90 line = dwarf_getsrc_die(cu_die, (Dwarf_Addr)addr);
91 if (line && dwarf_lineaddr(line, &laddr) == 0 &&
92 addr == (unsigned long)laddr && dwarf_lineno(line, lineno) == 0) {
93 *fname = dwarf_linesrc(line, NULL, NULL);
95 /* line number is useless without filename */
99 return *lineno ?: -ENOENT;
102 static int __die_find_inline_cb(Dwarf_Die *die_mem, void *data);
105 * cu_walk_functions_at - Walk on function DIEs at given address
108 * @callback: A callback which called with found DIEs
111 * Walk on function DIEs at given @addr in @cu_die. Passed DIEs
112 * should be subprogram or inlined-subroutines.
114 int cu_walk_functions_at(Dwarf_Die *cu_die, Dwarf_Addr addr,
115 int (*callback)(Dwarf_Die *, void *), void *data)
121 /* Inlined function could be recursive. Trace it until fail */
122 for (sc_die = die_find_realfunc(cu_die, addr, &die_mem);
124 sc_die = die_find_child(sc_die, __die_find_inline_cb, &addr,
126 ret = callback(sc_die, data);
136 * die_get_linkage_name - Get the linkage name of the object
137 * @dw_die: A DIE of the object
139 * Get the linkage name attiribute of given @dw_die.
140 * For C++ binary, the linkage name will be the mangled symbol.
142 const char *die_get_linkage_name(Dwarf_Die *dw_die)
144 Dwarf_Attribute attr;
146 if (dwarf_attr_integrate(dw_die, DW_AT_linkage_name, &attr) == NULL)
148 return dwarf_formstring(&attr);
152 * die_compare_name - Compare diename and tname
154 * @tname: a string of target name
156 * Compare the name of @dw_die and @tname. Return false if @dw_die has no name.
158 bool die_compare_name(Dwarf_Die *dw_die, const char *tname)
162 name = dwarf_diename(dw_die);
163 return name ? (strcmp(tname, name) == 0) : false;
167 * die_match_name - Match diename/linkage name and glob
169 * @glob: a string of target glob pattern
171 * Glob matching the name of @dw_die and @glob. Return false if matching fail.
172 * This also match linkage name.
174 bool die_match_name(Dwarf_Die *dw_die, const char *glob)
178 name = dwarf_diename(dw_die);
179 if (name && strglobmatch(name, glob))
181 /* fall back to check linkage name */
182 name = die_get_linkage_name(dw_die);
183 if (name && strglobmatch(name, glob))
190 * die_get_call_lineno - Get callsite line number of inline-function instance
191 * @in_die: a DIE of an inlined function instance
193 * Get call-site line number of @in_die. This means from where the inline
194 * function is called.
196 int die_get_call_lineno(Dwarf_Die *in_die)
198 Dwarf_Attribute attr;
201 if (!dwarf_attr(in_die, DW_AT_call_line, &attr))
204 dwarf_formudata(&attr, &ret);
209 * die_get_type - Get type DIE
210 * @vr_die: a DIE of a variable
211 * @die_mem: where to store a type DIE
213 * Get a DIE of the type of given variable (@vr_die), and store
214 * it to die_mem. Return NULL if fails to get a type DIE.
216 Dwarf_Die *die_get_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
218 Dwarf_Attribute attr;
220 if (dwarf_attr_integrate(vr_die, DW_AT_type, &attr) &&
221 dwarf_formref_die(&attr, die_mem))
227 /* Get a type die, but skip qualifiers */
228 static Dwarf_Die *__die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
233 vr_die = die_get_type(vr_die, die_mem);
236 tag = dwarf_tag(vr_die);
237 } while (tag == DW_TAG_const_type ||
238 tag == DW_TAG_restrict_type ||
239 tag == DW_TAG_volatile_type ||
240 tag == DW_TAG_shared_type);
246 * die_get_real_type - Get a type die, but skip qualifiers and typedef
247 * @vr_die: a DIE of a variable
248 * @die_mem: where to store a type DIE
250 * Get a DIE of the type of given variable (@vr_die), and store
251 * it to die_mem. Return NULL if fails to get a type DIE.
252 * If the type is qualifiers (e.g. const) or typedef, this skips it
253 * and tries to find real type (structure or basic types, e.g. int).
255 Dwarf_Die *die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
258 vr_die = __die_get_real_type(vr_die, die_mem);
259 } while (vr_die && dwarf_tag(vr_die) == DW_TAG_typedef);
264 /* Get attribute and translate it as a udata */
265 static int die_get_attr_udata(Dwarf_Die *tp_die, unsigned int attr_name,
268 Dwarf_Attribute attr;
270 if (dwarf_attr(tp_die, attr_name, &attr) == NULL ||
271 dwarf_formudata(&attr, result) != 0)
277 /* Get attribute and translate it as a sdata */
278 static int die_get_attr_sdata(Dwarf_Die *tp_die, unsigned int attr_name,
281 Dwarf_Attribute attr;
283 if (dwarf_attr(tp_die, attr_name, &attr) == NULL ||
284 dwarf_formsdata(&attr, result) != 0)
291 * die_is_signed_type - Check whether a type DIE is signed or not
292 * @tp_die: a DIE of a type
294 * Get the encoding of @tp_die and return true if the encoding
297 bool die_is_signed_type(Dwarf_Die *tp_die)
301 if (die_get_attr_udata(tp_die, DW_AT_encoding, &ret))
304 return (ret == DW_ATE_signed_char || ret == DW_ATE_signed ||
305 ret == DW_ATE_signed_fixed);
309 * die_is_func_def - Ensure that this DIE is a subprogram and definition
312 * Ensure that this DIE is a subprogram and NOT a declaration. This
313 * returns true if @dw_die is a function definition.
315 bool die_is_func_def(Dwarf_Die *dw_die)
317 Dwarf_Attribute attr;
319 return (dwarf_tag(dw_die) == DW_TAG_subprogram &&
320 dwarf_attr(dw_die, DW_AT_declaration, &attr) == NULL);
324 * die_is_func_instance - Ensure that this DIE is an instance of a subprogram
327 * Ensure that this DIE is an instance (which has an entry address).
328 * This returns true if @dw_die is a function instance. If not, you need to
329 * call die_walk_instances() to find actual instances.
331 bool die_is_func_instance(Dwarf_Die *dw_die)
335 /* Actually gcc optimizes non-inline as like as inlined */
336 return !dwarf_func_inline(dw_die) && dwarf_entrypc(dw_die, &tmp) == 0;
339 * die_get_data_member_location - Get the data-member offset
340 * @mb_die: a DIE of a member of a data structure
341 * @offs: The offset of the member in the data structure
343 * Get the offset of @mb_die in the data structure including @mb_die, and
344 * stores result offset to @offs. If any error occurs this returns errno.
346 int die_get_data_member_location(Dwarf_Die *mb_die, Dwarf_Word *offs)
348 Dwarf_Attribute attr;
353 if (dwarf_attr(mb_die, DW_AT_data_member_location, &attr) == NULL)
356 if (dwarf_formudata(&attr, offs) != 0) {
357 /* DW_AT_data_member_location should be DW_OP_plus_uconst */
358 ret = dwarf_getlocation(&attr, &expr, &nexpr);
359 if (ret < 0 || nexpr == 0)
362 if (expr[0].atom != DW_OP_plus_uconst || nexpr != 1) {
363 pr_debug("Unable to get offset:Unexpected OP %x (%zd)\n",
364 expr[0].atom, nexpr);
367 *offs = (Dwarf_Word)expr[0].number;
372 /* Get the call file index number in CU DIE */
373 static int die_get_call_fileno(Dwarf_Die *in_die)
377 if (die_get_attr_sdata(in_die, DW_AT_call_file, &idx) == 0)
383 /* Get the declared file index number in CU DIE */
384 static int die_get_decl_fileno(Dwarf_Die *pdie)
388 if (die_get_attr_sdata(pdie, DW_AT_decl_file, &idx) == 0)
395 * die_get_call_file - Get callsite file name of inlined function instance
396 * @in_die: a DIE of an inlined function instance
398 * Get call-site file name of @in_die. This means from which file the inline
399 * function is called.
401 const char *die_get_call_file(Dwarf_Die *in_die)
407 idx = die_get_call_fileno(in_die);
408 if (idx < 0 || !dwarf_diecu(in_die, &cu_die, NULL, NULL) ||
409 dwarf_getsrcfiles(&cu_die, &files, NULL) != 0)
412 return dwarf_filesrc(files, idx, NULL, NULL);
417 * die_find_child - Generic DIE search function in DIE tree
418 * @rt_die: a root DIE
419 * @callback: a callback function
420 * @data: a user data passed to the callback function
421 * @die_mem: a buffer for result DIE
423 * Trace DIE tree from @rt_die and call @callback for each child DIE.
424 * If @callback returns DIE_FIND_CB_END, this stores the DIE into
425 * @die_mem and returns it. If @callback returns DIE_FIND_CB_CONTINUE,
426 * this continues to trace the tree. Optionally, @callback can return
427 * DIE_FIND_CB_CHILD and DIE_FIND_CB_SIBLING, those means trace only
428 * the children and trace only the siblings respectively.
429 * Returns NULL if @callback can't find any appropriate DIE.
431 Dwarf_Die *die_find_child(Dwarf_Die *rt_die,
432 int (*callback)(Dwarf_Die *, void *),
433 void *data, Dwarf_Die *die_mem)
438 ret = dwarf_child(rt_die, die_mem);
443 ret = callback(die_mem, data);
444 if (ret == DIE_FIND_CB_END)
447 if ((ret & DIE_FIND_CB_CHILD) &&
448 die_find_child(die_mem, callback, data, &child_die)) {
449 memcpy(die_mem, &child_die, sizeof(Dwarf_Die));
452 } while ((ret & DIE_FIND_CB_SIBLING) &&
453 dwarf_siblingof(die_mem, die_mem) == 0);
458 struct __addr_die_search_param {
463 static int __die_search_func_tail_cb(Dwarf_Die *fn_die, void *data)
465 struct __addr_die_search_param *ad = data;
468 if (dwarf_tag(fn_die) == DW_TAG_subprogram &&
469 !dwarf_highpc(fn_die, &addr) &&
471 memcpy(ad->die_mem, fn_die, sizeof(Dwarf_Die));
472 return DWARF_CB_ABORT;
478 * die_find_tailfunc - Search for a non-inlined function with tail call at
480 * @cu_die: a CU DIE which including @addr
481 * @addr: target address
482 * @die_mem: a buffer for result DIE
484 * Search for a non-inlined function DIE with tail call at @addr. Stores the
485 * DIE to @die_mem and returns it if found. Returns NULL if failed.
487 Dwarf_Die *die_find_tailfunc(Dwarf_Die *cu_die, Dwarf_Addr addr,
490 struct __addr_die_search_param ad;
492 ad.die_mem = die_mem;
493 /* dwarf_getscopes can't find subprogram. */
494 if (!dwarf_getfuncs(cu_die, __die_search_func_tail_cb, &ad, 0))
500 /* die_find callback for non-inlined function search */
501 static int __die_search_func_cb(Dwarf_Die *fn_die, void *data)
503 struct __addr_die_search_param *ad = data;
506 * Since a declaration entry doesn't has given pc, this always returns
507 * function definition entry.
509 if (dwarf_tag(fn_die) == DW_TAG_subprogram &&
510 dwarf_haspc(fn_die, ad->addr)) {
511 memcpy(ad->die_mem, fn_die, sizeof(Dwarf_Die));
512 return DWARF_CB_ABORT;
518 * die_find_realfunc - Search a non-inlined function at given address
519 * @cu_die: a CU DIE which including @addr
520 * @addr: target address
521 * @die_mem: a buffer for result DIE
523 * Search a non-inlined function DIE which includes @addr. Stores the
524 * DIE to @die_mem and returns it if found. Returns NULL if failed.
526 Dwarf_Die *die_find_realfunc(Dwarf_Die *cu_die, Dwarf_Addr addr,
529 struct __addr_die_search_param ad;
531 ad.die_mem = die_mem;
532 /* dwarf_getscopes can't find subprogram. */
533 if (!dwarf_getfuncs(cu_die, __die_search_func_cb, &ad, 0))
539 /* die_find callback for inline function search */
540 static int __die_find_inline_cb(Dwarf_Die *die_mem, void *data)
542 Dwarf_Addr *addr = data;
544 if (dwarf_tag(die_mem) == DW_TAG_inlined_subroutine &&
545 dwarf_haspc(die_mem, *addr))
546 return DIE_FIND_CB_END;
548 return DIE_FIND_CB_CONTINUE;
552 * die_find_top_inlinefunc - Search the top inlined function at given address
553 * @sp_die: a subprogram DIE which including @addr
554 * @addr: target address
555 * @die_mem: a buffer for result DIE
557 * Search an inlined function DIE which includes @addr. Stores the
558 * DIE to @die_mem and returns it if found. Returns NULL if failed.
559 * Even if several inlined functions are expanded recursively, this
560 * doesn't trace it down, and returns the topmost one.
562 Dwarf_Die *die_find_top_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
565 return die_find_child(sp_die, __die_find_inline_cb, &addr, die_mem);
569 * die_find_inlinefunc - Search an inlined function at given address
570 * @sp_die: a subprogram DIE which including @addr
571 * @addr: target address
572 * @die_mem: a buffer for result DIE
574 * Search an inlined function DIE which includes @addr. Stores the
575 * DIE to @die_mem and returns it if found. Returns NULL if failed.
576 * If several inlined functions are expanded recursively, this trace
577 * it down and returns deepest one.
579 Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
584 sp_die = die_find_child(sp_die, __die_find_inline_cb, &addr, &tmp_die);
588 /* Inlined function could be recursive. Trace it until fail */
590 memcpy(die_mem, sp_die, sizeof(Dwarf_Die));
591 sp_die = die_find_child(sp_die, __die_find_inline_cb, &addr,
598 struct __instance_walk_param {
600 int (*callback)(Dwarf_Die *, void *);
605 static int __die_walk_instances_cb(Dwarf_Die *inst, void *data)
607 struct __instance_walk_param *iwp = data;
608 Dwarf_Attribute attr_mem;
609 Dwarf_Die origin_mem;
610 Dwarf_Attribute *attr;
614 attr = dwarf_attr(inst, DW_AT_abstract_origin, &attr_mem);
616 return DIE_FIND_CB_CONTINUE;
618 origin = dwarf_formref_die(attr, &origin_mem);
619 if (origin == NULL || origin->addr != iwp->addr)
620 return DIE_FIND_CB_CONTINUE;
622 /* Ignore redundant instances */
623 if (dwarf_tag(inst) == DW_TAG_inlined_subroutine) {
624 dwarf_decl_line(origin, &tmp);
625 if (die_get_call_lineno(inst) == tmp) {
626 tmp = die_get_decl_fileno(origin);
627 if (die_get_call_fileno(inst) == tmp)
628 return DIE_FIND_CB_CONTINUE;
632 iwp->retval = iwp->callback(inst, iwp->data);
634 return (iwp->retval) ? DIE_FIND_CB_END : DIE_FIND_CB_CONTINUE;
638 * die_walk_instances - Walk on instances of given DIE
639 * @or_die: an abstract original DIE
640 * @callback: a callback function which is called with instance DIE
643 * Walk on the instances of give @in_die. @in_die must be an inlined function
644 * declartion. This returns the return value of @callback if it returns
645 * non-zero value, or -ENOENT if there is no instance.
647 int die_walk_instances(Dwarf_Die *or_die, int (*callback)(Dwarf_Die *, void *),
652 struct __instance_walk_param iwp = {
653 .addr = or_die->addr,
654 .callback = callback,
659 if (dwarf_diecu(or_die, &cu_die, NULL, NULL) == NULL)
662 die_find_child(&cu_die, __die_walk_instances_cb, &iwp, &die_mem);
667 /* Line walker internal parameters */
668 struct __line_walk_param {
670 line_walk_callback_t callback;
675 static int __die_walk_funclines_cb(Dwarf_Die *in_die, void *data)
677 struct __line_walk_param *lw = data;
682 if (dwarf_tag(in_die) == DW_TAG_inlined_subroutine) {
683 fname = die_get_call_file(in_die);
684 lineno = die_get_call_lineno(in_die);
685 if (fname && lineno > 0 && dwarf_entrypc(in_die, &addr) == 0) {
686 lw->retval = lw->callback(fname, lineno, addr, lw->data);
688 return DIE_FIND_CB_END;
692 /* Don't need to search recursively */
693 return DIE_FIND_CB_SIBLING;
696 fname = dwarf_decl_file(in_die);
697 if (fname && dwarf_decl_line(in_die, &lineno) == 0) {
698 lw->retval = lw->callback(fname, lineno, addr, lw->data);
700 return DIE_FIND_CB_END;
704 /* Continue to search nested inlined function call-sites */
705 return DIE_FIND_CB_CONTINUE;
708 /* Walk on lines of blocks included in given DIE */
709 static int __die_walk_funclines(Dwarf_Die *sp_die, bool recursive,
710 line_walk_callback_t callback, void *data)
712 struct __line_walk_param lw = {
713 .recursive = recursive,
714 .callback = callback,
723 /* Handle function declaration line */
724 fname = dwarf_decl_file(sp_die);
725 if (fname && dwarf_decl_line(sp_die, &lineno) == 0 &&
726 dwarf_entrypc(sp_die, &addr) == 0) {
727 lw.retval = callback(fname, lineno, addr, data);
731 die_find_child(sp_die, __die_walk_funclines_cb, &lw, &die_mem);
736 static int __die_walk_culines_cb(Dwarf_Die *sp_die, void *data)
738 struct __line_walk_param *lw = data;
740 lw->retval = __die_walk_funclines(sp_die, true, lw->callback, lw->data);
742 return DWARF_CB_ABORT;
748 * die_walk_lines - Walk on lines inside given DIE
749 * @rt_die: a root DIE (CU, subprogram or inlined_subroutine)
750 * @callback: callback routine
753 * Walk on all lines inside given @rt_die and call @callback on each line.
754 * If the @rt_die is a function, walk only on the lines inside the function,
755 * otherwise @rt_die must be a CU DIE.
756 * Note that this walks not only dwarf line list, but also function entries
757 * and inline call-site.
759 int die_walk_lines(Dwarf_Die *rt_die, line_walk_callback_t callback, void *data)
764 const char *fname, *decf = NULL;
767 Dwarf_Die die_mem, *cu_die;
771 if (dwarf_tag(rt_die) != DW_TAG_compile_unit) {
772 cu_die = dwarf_diecu(rt_die, &die_mem, NULL, NULL);
773 dwarf_decl_line(rt_die, &decl);
774 decf = dwarf_decl_file(rt_die);
778 pr_debug2("Failed to get CU from given DIE.\n");
782 /* Get lines list in the CU */
783 if (dwarf_getsrclines(cu_die, &lines, &nlines) != 0) {
784 pr_debug2("Failed to get source lines on this CU.\n");
787 pr_debug2("Get %zd lines from this CU\n", nlines);
789 /* Walk on the lines on lines list */
790 for (i = 0; i < nlines; i++) {
791 line = dwarf_onesrcline(lines, i);
793 dwarf_lineno(line, &lineno) != 0 ||
794 dwarf_lineaddr(line, &addr) != 0) {
795 pr_debug2("Failed to get line info. "
796 "Possible error in debuginfo.\n");
799 /* Filter lines based on address */
800 if (rt_die != cu_die) {
803 * The line is included in given function, and
804 * no inline block includes it.
806 if (!dwarf_haspc(rt_die, addr))
808 if (die_find_inlinefunc(rt_die, addr, &die_mem)) {
809 dwarf_decl_line(&die_mem, &inl);
811 decf != dwarf_decl_file(&die_mem))
815 /* Get source line */
816 fname = dwarf_linesrc(line, NULL, NULL);
818 ret = callback(fname, lineno, addr, data);
824 * Dwarf lines doesn't include function declarations and inlined
825 * subroutines. We have to check functions list or given function.
827 if (rt_die != cu_die)
829 * Don't need walk functions recursively, because nested
830 * inlined functions don't have lines of the specified DIE.
832 ret = __die_walk_funclines(rt_die, false, callback, data);
834 struct __line_walk_param param = {
835 .callback = callback,
839 dwarf_getfuncs(cu_die, __die_walk_culines_cb, ¶m, 0);
846 struct __find_variable_param {
851 static int __die_find_variable_cb(Dwarf_Die *die_mem, void *data)
853 struct __find_variable_param *fvp = data;
854 Dwarf_Attribute attr;
857 tag = dwarf_tag(die_mem);
858 if ((tag == DW_TAG_formal_parameter ||
859 tag == DW_TAG_variable) &&
860 die_compare_name(die_mem, fvp->name) &&
861 /* Does the DIE have location information or external instance? */
862 (dwarf_attr(die_mem, DW_AT_external, &attr) ||
863 dwarf_attr(die_mem, DW_AT_location, &attr)))
864 return DIE_FIND_CB_END;
865 if (dwarf_haspc(die_mem, fvp->addr))
866 return DIE_FIND_CB_CONTINUE;
868 return DIE_FIND_CB_SIBLING;
872 * die_find_variable_at - Find a given name variable at given address
873 * @sp_die: a function DIE
874 * @name: variable name
876 * @die_mem: a buffer for result DIE
878 * Find a variable DIE called @name at @addr in @sp_die.
880 Dwarf_Die *die_find_variable_at(Dwarf_Die *sp_die, const char *name,
881 Dwarf_Addr addr, Dwarf_Die *die_mem)
883 struct __find_variable_param fvp = { .name = name, .addr = addr};
885 return die_find_child(sp_die, __die_find_variable_cb, (void *)&fvp,
889 static int __die_find_member_cb(Dwarf_Die *die_mem, void *data)
891 const char *name = data;
893 if (dwarf_tag(die_mem) == DW_TAG_member) {
894 if (die_compare_name(die_mem, name))
895 return DIE_FIND_CB_END;
896 else if (!dwarf_diename(die_mem)) { /* Unnamed structure */
897 Dwarf_Die type_die, tmp_die;
898 if (die_get_type(die_mem, &type_die) &&
899 die_find_member(&type_die, name, &tmp_die))
900 return DIE_FIND_CB_END;
903 return DIE_FIND_CB_SIBLING;
907 * die_find_member - Find a given name member in a data structure
908 * @st_die: a data structure type DIE
910 * @die_mem: a buffer for result DIE
912 * Find a member DIE called @name in @st_die.
914 Dwarf_Die *die_find_member(Dwarf_Die *st_die, const char *name,
917 return die_find_child(st_die, __die_find_member_cb, (void *)name,
922 * die_get_typename - Get the name of given variable DIE
923 * @vr_die: a variable DIE
924 * @buf: a strbuf for result type name
926 * Get the name of @vr_die and stores it to @buf. Return 0 if succeeded.
927 * and Return -ENOENT if failed to find type name.
928 * Note that the result will stores typedef name if possible, and stores
929 * "*(function_type)" if the type is a function pointer.
931 int die_get_typename(Dwarf_Die *vr_die, struct strbuf *buf)
935 const char *tmp = "";
937 if (__die_get_real_type(vr_die, &type) == NULL)
940 tag = dwarf_tag(&type);
941 if (tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)
943 else if (tag == DW_TAG_subroutine_type) {
944 /* Function pointer */
945 return strbuf_add(buf, "(function_type)", 15);
947 if (!dwarf_diename(&type))
949 if (tag == DW_TAG_union_type)
951 else if (tag == DW_TAG_structure_type)
953 else if (tag == DW_TAG_enumeration_type)
955 /* Write a base name */
956 return strbuf_addf(buf, "%s%s", tmp, dwarf_diename(&type));
958 ret = die_get_typename(&type, buf);
959 return ret ? ret : strbuf_addstr(buf, tmp);
963 * die_get_varname - Get the name and type of given variable DIE
964 * @vr_die: a variable DIE
965 * @buf: a strbuf for type and variable name
967 * Get the name and type of @vr_die and stores it in @buf as "type\tname".
969 int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf)
973 ret = die_get_typename(vr_die, buf);
975 pr_debug("Failed to get type, make it unknown.\n");
976 ret = strbuf_add(buf, " (unknown_type)", 14);
979 return ret < 0 ? ret : strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
982 #ifdef HAVE_DWARF_GETLOCATIONS
984 * die_get_var_innermost_scope - Get innermost scope range of given variable DIE
985 * @sp_die: a subprogram DIE
986 * @vr_die: a variable DIE
987 * @buf: a strbuf for variable byte offset range
989 * Get the innermost scope range of @vr_die and stores it in @buf as
990 * "@<function_name+[NN-NN,NN-NN]>".
992 static int die_get_var_innermost_scope(Dwarf_Die *sp_die, Dwarf_Die *vr_die,
999 Dwarf_Addr start, end;
1005 ret = dwarf_entrypc(sp_die, &entry);
1009 name = dwarf_diename(sp_die);
1013 count = dwarf_getscopes_die(vr_die, &scopes);
1015 /* (*SCOPES)[1] is the DIE for the scope containing that scope */
1021 while ((offset = dwarf_ranges(&scopes[1], offset, &base,
1022 &start, &end)) > 0) {
1027 ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
1031 ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
1039 ret = strbuf_add(buf, "]>", 2);
1047 * die_get_var_range - Get byte offset range of given variable DIE
1048 * @sp_die: a subprogram DIE
1049 * @vr_die: a variable DIE
1050 * @buf: a strbuf for type and variable name and byte offset range
1052 * Get the byte offset range of @vr_die and stores it in @buf as
1053 * "@<function_name+[NN-NN,NN-NN]>".
1055 int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf)
1059 Dwarf_Addr start, end;
1064 Dwarf_Attribute attr;
1068 ret = dwarf_entrypc(sp_die, &entry);
1072 name = dwarf_diename(sp_die);
1076 if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL)
1079 while ((offset = dwarf_getlocations(&attr, offset, &base,
1080 &start, &end, &op, &nops)) > 0) {
1082 /* Single Location Descriptions */
1083 ret = die_get_var_innermost_scope(sp_die, vr_die, buf);
1087 /* Location Lists */
1091 ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
1095 ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
1103 ret = strbuf_add(buf, "]>", 2);
1108 int die_get_var_range(Dwarf_Die *sp_die __maybe_unused,
1109 Dwarf_Die *vr_die __maybe_unused,
1110 struct strbuf *buf __maybe_unused)
1117 * die_has_loclist - Check if DW_AT_location of @vr_die is a location list
1118 * @vr_die: a variable DIE
1120 static bool die_has_loclist(Dwarf_Die *vr_die)
1122 Dwarf_Attribute loc;
1123 int tag = dwarf_tag(vr_die);
1125 if (tag != DW_TAG_formal_parameter &&
1126 tag != DW_TAG_variable)
1129 return (dwarf_attr_integrate(vr_die, DW_AT_location, &loc) &&
1130 dwarf_whatform(&loc) == DW_FORM_sec_offset);
1134 * die_is_optimized_target - Check if target program is compiled with
1138 * For any object in given CU whose DW_AT_location is a location list,
1139 * target program is compiled with optimization. This is applicable to
1142 bool die_is_optimized_target(Dwarf_Die *cu_die)
1146 if (die_has_loclist(cu_die))
1149 if (!dwarf_child(cu_die, &tmp_die) &&
1150 die_is_optimized_target(&tmp_die))
1153 if (!dwarf_siblingof(cu_die, &tmp_die) &&
1154 die_is_optimized_target(&tmp_die))
1161 * die_search_idx - Search index of given line address
1162 * @lines: Line records of single CU
1163 * @nr_lines: Number of @lines
1164 * @addr: address we are looking for
1165 * @idx: index to be set by this function (return value)
1167 * Search for @addr by looping over every lines of CU. If address
1168 * matches, set index of that line in @idx. Note that single source
1169 * line can have multiple line records. i.e. single source line can
1170 * have multiple index.
1172 static bool die_search_idx(Dwarf_Lines *lines, unsigned long nr_lines,
1173 Dwarf_Addr addr, unsigned long *idx)
1178 for (i = 0; i < nr_lines; i++) {
1179 if (dwarf_lineaddr(dwarf_onesrcline(lines, i), &tmp))
1191 * die_get_postprologue_addr - Search next address after function prologue
1192 * @entrypc_idx: entrypc index
1193 * @lines: Line records of single CU
1194 * @nr_lines: Number of @lines
1195 * @hignpc: high PC address of function
1196 * @postprologue_addr: Next address after function prologue (return value)
1198 * Look for prologue-end marker. If there is no explicit marker, return
1199 * address of next line record or next source line.
1201 static bool die_get_postprologue_addr(unsigned long entrypc_idx,
1203 unsigned long nr_lines,
1205 Dwarf_Addr *postprologue_addr)
1208 int entrypc_lno, lno;
1213 /* entrypc_lno is actual source line number */
1214 line = dwarf_onesrcline(lines, entrypc_idx);
1215 if (dwarf_lineno(line, &entrypc_lno))
1218 for (i = entrypc_idx; i < nr_lines; i++) {
1219 line = dwarf_onesrcline(lines, i);
1221 if (dwarf_lineaddr(line, &addr) ||
1222 dwarf_lineno(line, &lno) ||
1223 dwarf_lineprologueend(line, &p_end))
1226 /* highpc is exclusive. [entrypc,highpc) */
1230 /* clang supports prologue-end marker */
1234 /* Actual next line in source */
1235 if (lno != entrypc_lno)
1239 * Single source line can have multiple line records.
1241 * void foo() { printf("hello\n"); }
1242 * contains two line records. One points to declaration and
1243 * other points to printf() line. Variable 'lno' won't get
1244 * incremented in this case but 'i' will.
1246 if (i != entrypc_idx)
1250 dwarf_lineaddr(line, postprologue_addr);
1251 if (*postprologue_addr >= highpc)
1252 dwarf_lineaddr(dwarf_onesrcline(lines, i - 1),
1259 * die_skip_prologue - Use next address after prologue as probe location
1260 * @sp_die: a subprogram DIE
1262 * @entrypc: entrypc of the function
1264 * Function prologue prepares stack and registers before executing function
1265 * logic. When target program is compiled without optimization, function
1266 * parameter information is only valid after prologue. When we probe entrypc
1267 * of the function, and try to record function parameter, it contains
1270 void die_skip_prologue(Dwarf_Die *sp_die, Dwarf_Die *cu_die,
1271 Dwarf_Addr *entrypc)
1273 size_t nr_lines = 0;
1274 unsigned long entrypc_idx = 0;
1275 Dwarf_Lines *lines = NULL;
1276 Dwarf_Addr postprologue_addr;
1279 if (dwarf_highpc(sp_die, &highpc))
1282 if (dwarf_getsrclines(cu_die, &lines, &nr_lines))
1285 if (!die_search_idx(lines, nr_lines, *entrypc, &entrypc_idx))
1288 if (!die_get_postprologue_addr(entrypc_idx, lines, nr_lines,
1289 highpc, &postprologue_addr))
1292 *entrypc = postprologue_addr;