1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * dwarf-aux.c : libdw auxiliary interfaces
11 #include "dwarf-aux.h"
16 * cu_find_realpath - Find the realpath of the target file
17 * @cu_die: A DIE(dwarf information entry) of CU(compilation Unit)
18 * @fname: The tail filename of the target file
20 * Find the real(long) path of @fname in @cu_die.
22 const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname)
26 const char *src = NULL;
32 ret = dwarf_getsrcfiles(cu_die, &files, &nfiles);
36 for (i = 0; i < nfiles; i++) {
37 src = dwarf_filesrc(files, i, NULL, NULL);
38 if (strtailcmp(src, fname) == 0)
47 * cu_get_comp_dir - Get the path of compilation directory
50 * Get the path of compilation directory of given @cu_die.
51 * Since this depends on DW_AT_comp_dir, older gcc will not
52 * embedded it. In that case, this returns NULL.
54 const char *cu_get_comp_dir(Dwarf_Die *cu_die)
57 if (dwarf_attr(cu_die, DW_AT_comp_dir, &attr) == NULL)
59 return dwarf_formstring(&attr);
62 /* Unlike dwarf_getsrc_die(), cu_getsrc_die() only returns statement line */
63 static Dwarf_Line *cu_getsrc_die(Dwarf_Die *cu_die, Dwarf_Addr addr)
68 size_t nlines, l, u, n;
71 if (dwarf_getsrclines(cu_die, &lines, &nlines) != 0 ||
75 /* Lines are sorted by address, use binary search */
76 l = 0; u = nlines - 1;
79 line = dwarf_onesrcline(lines, n);
80 if (!line || dwarf_lineaddr(line, &laddr) != 0)
87 /* Going backward to find the lowest line */
89 line = dwarf_onesrcline(lines, --l);
90 if (!line || dwarf_lineaddr(line, &laddr) != 0)
92 } while (laddr == addr);
94 /* Going forward to find the statement line */
96 line = dwarf_onesrcline(lines, l++);
97 if (!line || dwarf_lineaddr(line, &laddr) != 0 ||
98 dwarf_linebeginstatement(line, &flag) != 0)
108 * cu_find_lineinfo - Get a line number and file name for given address
111 * @fname: a pointer which returns the file name string
112 * @lineno: a pointer which returns the line number
114 * Find a line number and file name for @addr in @cu_die.
116 int cu_find_lineinfo(Dwarf_Die *cu_die, Dwarf_Addr addr,
117 const char **fname, int *lineno)
123 if (die_find_realfunc(cu_die, addr, &die_mem)
124 && die_entrypc(&die_mem, &faddr) == 0 &&
126 *fname = die_get_decl_file(&die_mem);
127 dwarf_decl_line(&die_mem, lineno);
131 line = cu_getsrc_die(cu_die, addr);
132 if (line && dwarf_lineno(line, lineno) == 0) {
133 *fname = dwarf_linesrc(line, NULL, NULL);
135 /* line number is useless without filename */
140 return (*lineno && *fname) ? *lineno : -ENOENT;
143 static int __die_find_inline_cb(Dwarf_Die *die_mem, void *data);
146 * cu_walk_functions_at - Walk on function DIEs at given address
149 * @callback: A callback which called with found DIEs
152 * Walk on function DIEs at given @addr in @cu_die. Passed DIEs
153 * should be subprogram or inlined-subroutines.
155 int cu_walk_functions_at(Dwarf_Die *cu_die, Dwarf_Addr addr,
156 int (*callback)(Dwarf_Die *, void *), void *data)
162 /* Inlined function could be recursive. Trace it until fail */
163 for (sc_die = die_find_realfunc(cu_die, addr, &die_mem);
165 sc_die = die_find_child(sc_die, __die_find_inline_cb, &addr,
167 ret = callback(sc_die, data);
177 * die_get_linkage_name - Get the linkage name of the object
178 * @dw_die: A DIE of the object
180 * Get the linkage name attribute of given @dw_die.
181 * For C++ binary, the linkage name will be the mangled symbol.
183 const char *die_get_linkage_name(Dwarf_Die *dw_die)
185 Dwarf_Attribute attr;
187 if (dwarf_attr_integrate(dw_die, DW_AT_linkage_name, &attr) == NULL)
189 return dwarf_formstring(&attr);
193 * die_compare_name - Compare diename and tname
195 * @tname: a string of target name
197 * Compare the name of @dw_die and @tname. Return false if @dw_die has no name.
199 bool die_compare_name(Dwarf_Die *dw_die, const char *tname)
203 name = dwarf_diename(dw_die);
204 return name ? (strcmp(tname, name) == 0) : false;
208 * die_match_name - Match diename/linkage name and glob
210 * @glob: a string of target glob pattern
212 * Glob matching the name of @dw_die and @glob. Return false if matching fail.
213 * This also match linkage name.
215 bool die_match_name(Dwarf_Die *dw_die, const char *glob)
219 name = dwarf_diename(dw_die);
220 if (name && strglobmatch(name, glob))
222 /* fall back to check linkage name */
223 name = die_get_linkage_name(dw_die);
224 if (name && strglobmatch(name, glob))
231 * die_get_call_lineno - Get callsite line number of inline-function instance
232 * @in_die: a DIE of an inlined function instance
234 * Get call-site line number of @in_die. This means from where the inline
235 * function is called.
237 int die_get_call_lineno(Dwarf_Die *in_die)
239 Dwarf_Attribute attr;
242 if (!dwarf_attr(in_die, DW_AT_call_line, &attr))
245 dwarf_formudata(&attr, &ret);
250 * die_get_type - Get type DIE
251 * @vr_die: a DIE of a variable
252 * @die_mem: where to store a type DIE
254 * Get a DIE of the type of given variable (@vr_die), and store
255 * it to die_mem. Return NULL if fails to get a type DIE.
257 Dwarf_Die *die_get_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
259 Dwarf_Attribute attr;
261 if (dwarf_attr_integrate(vr_die, DW_AT_type, &attr) &&
262 dwarf_formref_die(&attr, die_mem))
268 /* Get a type die, but skip qualifiers */
269 static Dwarf_Die *__die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
274 vr_die = die_get_type(vr_die, die_mem);
277 tag = dwarf_tag(vr_die);
278 } while (tag == DW_TAG_const_type ||
279 tag == DW_TAG_restrict_type ||
280 tag == DW_TAG_volatile_type ||
281 tag == DW_TAG_shared_type);
287 * die_get_real_type - Get a type die, but skip qualifiers and typedef
288 * @vr_die: a DIE of a variable
289 * @die_mem: where to store a type DIE
291 * Get a DIE of the type of given variable (@vr_die), and store
292 * it to die_mem. Return NULL if fails to get a type DIE.
293 * If the type is qualifiers (e.g. const) or typedef, this skips it
294 * and tries to find real type (structure or basic types, e.g. int).
296 Dwarf_Die *die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
299 vr_die = __die_get_real_type(vr_die, die_mem);
300 } while (vr_die && dwarf_tag(vr_die) == DW_TAG_typedef);
305 /* Get attribute and translate it as a udata */
306 static int die_get_attr_udata(Dwarf_Die *tp_die, unsigned int attr_name,
309 Dwarf_Attribute attr;
311 if (dwarf_attr_integrate(tp_die, attr_name, &attr) == NULL ||
312 dwarf_formudata(&attr, result) != 0)
319 * die_is_signed_type - Check whether a type DIE is signed or not
320 * @tp_die: a DIE of a type
322 * Get the encoding of @tp_die and return true if the encoding
325 bool die_is_signed_type(Dwarf_Die *tp_die)
329 if (die_get_attr_udata(tp_die, DW_AT_encoding, &ret))
332 return (ret == DW_ATE_signed_char || ret == DW_ATE_signed ||
333 ret == DW_ATE_signed_fixed);
337 * die_is_func_def - Ensure that this DIE is a subprogram and definition
340 * Ensure that this DIE is a subprogram and NOT a declaration. This
341 * returns true if @dw_die is a function definition.
343 bool die_is_func_def(Dwarf_Die *dw_die)
345 Dwarf_Attribute attr;
348 if (dwarf_tag(dw_die) != DW_TAG_subprogram)
351 if (dwarf_attr(dw_die, DW_AT_declaration, &attr))
355 * DW_AT_declaration can be lost from function declaration
356 * by gcc's bug #97060.
357 * So we need to check this subprogram DIE has DW_AT_inline
358 * or an entry address.
360 if (!dwarf_attr(dw_die, DW_AT_inline, &attr) &&
361 die_entrypc(dw_die, &addr) < 0)
368 * die_entrypc - Returns entry PC (the lowest address) of a DIE
370 * @addr: where to store entry PC
372 * Since dwarf_entrypc() does not return entry PC if the DIE has only address
373 * range, we have to use this to retrieve the lowest address from the address
376 int die_entrypc(Dwarf_Die *dw_die, Dwarf_Addr *addr)
378 Dwarf_Addr base, end;
379 Dwarf_Attribute attr;
384 if (dwarf_entrypc(dw_die, addr) == 0)
388 * Since the dwarf_ranges() will return 0 if there is no
389 * DW_AT_ranges attribute, we should check it first.
391 if (!dwarf_attr(dw_die, DW_AT_ranges, &attr))
394 return dwarf_ranges(dw_die, 0, &base, addr, &end) < 0 ? -ENOENT : 0;
398 * die_is_func_instance - Ensure that this DIE is an instance of a subprogram
401 * Ensure that this DIE is an instance (which has an entry address).
402 * This returns true if @dw_die is a function instance. If not, the @dw_die
403 * must be a prototype. You can use die_walk_instances() to find actual
406 bool die_is_func_instance(Dwarf_Die *dw_die)
409 Dwarf_Attribute attr_mem;
410 int tag = dwarf_tag(dw_die);
412 if (tag != DW_TAG_subprogram &&
413 tag != DW_TAG_inlined_subroutine)
416 return dwarf_entrypc(dw_die, &tmp) == 0 ||
417 dwarf_attr(dw_die, DW_AT_ranges, &attr_mem) != NULL;
421 * die_get_data_member_location - Get the data-member offset
422 * @mb_die: a DIE of a member of a data structure
423 * @offs: The offset of the member in the data structure
425 * Get the offset of @mb_die in the data structure including @mb_die, and
426 * stores result offset to @offs. If any error occurs this returns errno.
428 int die_get_data_member_location(Dwarf_Die *mb_die, Dwarf_Word *offs)
430 Dwarf_Attribute attr;
435 if (dwarf_attr(mb_die, DW_AT_data_member_location, &attr) == NULL)
438 if (dwarf_formudata(&attr, offs) != 0) {
439 /* DW_AT_data_member_location should be DW_OP_plus_uconst */
440 ret = dwarf_getlocation(&attr, &expr, &nexpr);
441 if (ret < 0 || nexpr == 0)
444 if (expr[0].atom != DW_OP_plus_uconst || nexpr != 1) {
445 pr_debug("Unable to get offset:Unexpected OP %x (%zd)\n",
446 expr[0].atom, nexpr);
449 *offs = (Dwarf_Word)expr[0].number;
454 /* Get the call file index number in CU DIE */
455 static int die_get_call_fileno(Dwarf_Die *in_die)
459 if (die_get_attr_udata(in_die, DW_AT_call_file, &idx) == 0)
465 /* Get the declared file index number in CU DIE */
466 static int die_get_decl_fileno(Dwarf_Die *pdie)
470 if (die_get_attr_udata(pdie, DW_AT_decl_file, &idx) == 0)
476 /* Return the file name by index */
477 static const char *die_get_file_name(Dwarf_Die *dw_die, int idx)
482 if (idx < 0 || !dwarf_diecu(dw_die, &cu_die, NULL, NULL) ||
483 dwarf_getsrcfiles(&cu_die, &files, NULL) != 0)
486 return dwarf_filesrc(files, idx, NULL, NULL);
490 * die_get_call_file - Get callsite file name of inlined function instance
491 * @in_die: a DIE of an inlined function instance
493 * Get call-site file name of @in_die. This means from which file the inline
494 * function is called.
496 const char *die_get_call_file(Dwarf_Die *in_die)
498 return die_get_file_name(in_die, die_get_call_fileno(in_die));
502 * die_get_decl_file - Find the declared file name of this DIE
503 * @dw_die: a DIE for something declared.
505 * Get declared file name of @dw_die.
506 * NOTE: Since some version of clang DWARF5 implementation incorrectly uses
507 * file index 0 for DW_AT_decl_file, die_get_decl_file() will return NULL for
508 * such cases. Use this function instead.
510 const char *die_get_decl_file(Dwarf_Die *dw_die)
512 return die_get_file_name(dw_die, die_get_decl_fileno(dw_die));
516 * die_find_child - Generic DIE search function in DIE tree
517 * @rt_die: a root DIE
518 * @callback: a callback function
519 * @data: a user data passed to the callback function
520 * @die_mem: a buffer for result DIE
522 * Trace DIE tree from @rt_die and call @callback for each child DIE.
523 * If @callback returns DIE_FIND_CB_END, this stores the DIE into
524 * @die_mem and returns it. If @callback returns DIE_FIND_CB_CONTINUE,
525 * this continues to trace the tree. Optionally, @callback can return
526 * DIE_FIND_CB_CHILD and DIE_FIND_CB_SIBLING, those means trace only
527 * the children and trace only the siblings respectively.
528 * Returns NULL if @callback can't find any appropriate DIE.
530 Dwarf_Die *die_find_child(Dwarf_Die *rt_die,
531 int (*callback)(Dwarf_Die *, void *),
532 void *data, Dwarf_Die *die_mem)
537 ret = dwarf_child(rt_die, die_mem);
542 ret = callback(die_mem, data);
543 if (ret == DIE_FIND_CB_END)
546 if ((ret & DIE_FIND_CB_CHILD) &&
547 die_find_child(die_mem, callback, data, &child_die)) {
548 memcpy(die_mem, &child_die, sizeof(Dwarf_Die));
551 } while ((ret & DIE_FIND_CB_SIBLING) &&
552 dwarf_siblingof(die_mem, die_mem) == 0);
557 struct __addr_die_search_param {
562 static int __die_search_func_tail_cb(Dwarf_Die *fn_die, void *data)
564 struct __addr_die_search_param *ad = data;
567 if (dwarf_tag(fn_die) == DW_TAG_subprogram &&
568 !dwarf_highpc(fn_die, &addr) &&
570 memcpy(ad->die_mem, fn_die, sizeof(Dwarf_Die));
571 return DWARF_CB_ABORT;
577 * die_find_tailfunc - Search for a non-inlined function with tail call at
579 * @cu_die: a CU DIE which including @addr
580 * @addr: target address
581 * @die_mem: a buffer for result DIE
583 * Search for a non-inlined function DIE with tail call at @addr. Stores the
584 * DIE to @die_mem and returns it if found. Returns NULL if failed.
586 Dwarf_Die *die_find_tailfunc(Dwarf_Die *cu_die, Dwarf_Addr addr,
589 struct __addr_die_search_param ad;
591 ad.die_mem = die_mem;
592 /* dwarf_getscopes can't find subprogram. */
593 if (!dwarf_getfuncs(cu_die, __die_search_func_tail_cb, &ad, 0))
599 /* die_find callback for non-inlined function search */
600 static int __die_search_func_cb(Dwarf_Die *fn_die, void *data)
602 struct __addr_die_search_param *ad = data;
605 * Since a declaration entry doesn't has given pc, this always returns
606 * function definition entry.
608 if (dwarf_tag(fn_die) == DW_TAG_subprogram &&
609 dwarf_haspc(fn_die, ad->addr)) {
610 memcpy(ad->die_mem, fn_die, sizeof(Dwarf_Die));
611 return DWARF_CB_ABORT;
617 * die_find_realfunc - Search a non-inlined function at given address
618 * @cu_die: a CU DIE which including @addr
619 * @addr: target address
620 * @die_mem: a buffer for result DIE
622 * Search a non-inlined function DIE which includes @addr. Stores the
623 * DIE to @die_mem and returns it if found. Returns NULL if failed.
625 Dwarf_Die *die_find_realfunc(Dwarf_Die *cu_die, Dwarf_Addr addr,
628 struct __addr_die_search_param ad;
630 ad.die_mem = die_mem;
631 /* dwarf_getscopes can't find subprogram. */
632 if (!dwarf_getfuncs(cu_die, __die_search_func_cb, &ad, 0))
638 /* die_find callback for inline function search */
639 static int __die_find_inline_cb(Dwarf_Die *die_mem, void *data)
641 Dwarf_Addr *addr = data;
643 if (dwarf_tag(die_mem) == DW_TAG_inlined_subroutine &&
644 dwarf_haspc(die_mem, *addr))
645 return DIE_FIND_CB_END;
647 return DIE_FIND_CB_CONTINUE;
651 * die_find_top_inlinefunc - Search the top inlined function at given address
652 * @sp_die: a subprogram DIE which including @addr
653 * @addr: target address
654 * @die_mem: a buffer for result DIE
656 * Search an inlined function DIE which includes @addr. Stores the
657 * DIE to @die_mem and returns it if found. Returns NULL if failed.
658 * Even if several inlined functions are expanded recursively, this
659 * doesn't trace it down, and returns the topmost one.
661 Dwarf_Die *die_find_top_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
664 return die_find_child(sp_die, __die_find_inline_cb, &addr, die_mem);
668 * die_find_inlinefunc - Search an inlined function at given address
669 * @sp_die: a subprogram DIE which including @addr
670 * @addr: target address
671 * @die_mem: a buffer for result DIE
673 * Search an inlined function DIE which includes @addr. Stores the
674 * DIE to @die_mem and returns it if found. Returns NULL if failed.
675 * If several inlined functions are expanded recursively, this trace
676 * it down and returns deepest one.
678 Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
683 sp_die = die_find_child(sp_die, __die_find_inline_cb, &addr, &tmp_die);
687 /* Inlined function could be recursive. Trace it until fail */
689 memcpy(die_mem, sp_die, sizeof(Dwarf_Die));
690 sp_die = die_find_child(sp_die, __die_find_inline_cb, &addr,
697 struct __instance_walk_param {
699 int (*callback)(Dwarf_Die *, void *);
704 static int __die_walk_instances_cb(Dwarf_Die *inst, void *data)
706 struct __instance_walk_param *iwp = data;
707 Dwarf_Attribute attr_mem;
708 Dwarf_Die origin_mem;
709 Dwarf_Attribute *attr;
713 if (!die_is_func_instance(inst))
714 return DIE_FIND_CB_CONTINUE;
716 attr = dwarf_attr(inst, DW_AT_abstract_origin, &attr_mem);
718 return DIE_FIND_CB_CONTINUE;
720 origin = dwarf_formref_die(attr, &origin_mem);
721 if (origin == NULL || origin->addr != iwp->addr)
722 return DIE_FIND_CB_CONTINUE;
724 /* Ignore redundant instances */
725 if (dwarf_tag(inst) == DW_TAG_inlined_subroutine) {
726 dwarf_decl_line(origin, &tmp);
727 if (die_get_call_lineno(inst) == tmp) {
728 tmp = die_get_decl_fileno(origin);
729 if (die_get_call_fileno(inst) == tmp)
730 return DIE_FIND_CB_CONTINUE;
734 iwp->retval = iwp->callback(inst, iwp->data);
736 return (iwp->retval) ? DIE_FIND_CB_END : DIE_FIND_CB_CONTINUE;
740 * die_walk_instances - Walk on instances of given DIE
741 * @or_die: an abstract original DIE
742 * @callback: a callback function which is called with instance DIE
745 * Walk on the instances of give @in_die. @in_die must be an inlined function
746 * declaration. This returns the return value of @callback if it returns
747 * non-zero value, or -ENOENT if there is no instance.
749 int die_walk_instances(Dwarf_Die *or_die, int (*callback)(Dwarf_Die *, void *),
754 struct __instance_walk_param iwp = {
755 .addr = or_die->addr,
756 .callback = callback,
761 if (dwarf_diecu(or_die, &cu_die, NULL, NULL) == NULL)
764 die_find_child(&cu_die, __die_walk_instances_cb, &iwp, &die_mem);
769 /* Line walker internal parameters */
770 struct __line_walk_param {
772 line_walk_callback_t callback;
777 static int __die_walk_funclines_cb(Dwarf_Die *in_die, void *data)
779 struct __line_walk_param *lw = data;
784 if (dwarf_tag(in_die) == DW_TAG_inlined_subroutine) {
785 fname = die_get_call_file(in_die);
786 lineno = die_get_call_lineno(in_die);
787 if (fname && lineno > 0 && die_entrypc(in_die, &addr) == 0) {
788 lw->retval = lw->callback(fname, lineno, addr, lw->data);
790 return DIE_FIND_CB_END;
793 return DIE_FIND_CB_SIBLING;
797 fname = die_get_decl_file(in_die);
798 if (fname && dwarf_decl_line(in_die, &lineno) == 0) {
799 lw->retval = lw->callback(fname, lineno, addr, lw->data);
801 return DIE_FIND_CB_END;
805 /* Continue to search nested inlined function call-sites */
806 return DIE_FIND_CB_CONTINUE;
809 /* Walk on lines of blocks included in given DIE */
810 static int __die_walk_funclines(Dwarf_Die *sp_die, bool recursive,
811 line_walk_callback_t callback, void *data)
813 struct __line_walk_param lw = {
814 .recursive = recursive,
815 .callback = callback,
824 /* Handle function declaration line */
825 fname = die_get_decl_file(sp_die);
826 if (fname && dwarf_decl_line(sp_die, &lineno) == 0 &&
827 die_entrypc(sp_die, &addr) == 0) {
828 lw.retval = callback(fname, lineno, addr, data);
832 die_find_child(sp_die, __die_walk_funclines_cb, &lw, &die_mem);
837 static int __die_walk_culines_cb(Dwarf_Die *sp_die, void *data)
839 struct __line_walk_param *lw = data;
842 * Since inlined function can include another inlined function in
843 * the same file, we need to walk in it recursively.
845 lw->retval = __die_walk_funclines(sp_die, true, lw->callback, lw->data);
847 return DWARF_CB_ABORT;
853 * die_walk_lines - Walk on lines inside given DIE
854 * @rt_die: a root DIE (CU, subprogram or inlined_subroutine)
855 * @callback: callback routine
858 * Walk on all lines inside given @rt_die and call @callback on each line.
859 * If the @rt_die is a function, walk only on the lines inside the function,
860 * otherwise @rt_die must be a CU DIE.
861 * Note that this walks not only dwarf line list, but also function entries
862 * and inline call-site.
864 int die_walk_lines(Dwarf_Die *rt_die, line_walk_callback_t callback, void *data)
869 const char *fname, *decf = NULL, *inf = NULL;
872 Dwarf_Die die_mem, *cu_die;
877 if (dwarf_tag(rt_die) != DW_TAG_compile_unit) {
878 cu_die = dwarf_diecu(rt_die, &die_mem, NULL, NULL);
879 dwarf_decl_line(rt_die, &decl);
880 decf = die_get_decl_file(rt_die);
882 pr_debug2("Failed to get the declared file name of %s\n",
883 dwarf_diename(rt_die));
889 pr_debug2("Failed to get CU from given DIE.\n");
893 /* Get lines list in the CU */
894 if (dwarf_getsrclines(cu_die, &lines, &nlines) != 0) {
895 pr_debug2("Failed to get source lines on this CU.\n");
898 pr_debug2("Get %zd lines from this CU\n", nlines);
900 /* Walk on the lines on lines list */
901 for (i = 0; i < nlines; i++) {
902 line = dwarf_onesrcline(lines, i);
904 dwarf_lineno(line, &lineno) != 0 ||
905 dwarf_lineaddr(line, &addr) != 0) {
906 pr_debug2("Failed to get line info. "
907 "Possible error in debuginfo.\n");
910 /* Skip end-of-sequence */
911 if (dwarf_lineendsequence(line, &flag) != 0 || flag)
913 /* Skip Non statement line-info */
914 if (dwarf_linebeginstatement(line, &flag) != 0 || !flag)
916 /* Filter lines based on address */
917 if (rt_die != cu_die) {
920 * The line is included in given function, and
921 * no inline block includes it.
923 if (!dwarf_haspc(rt_die, addr))
926 if (die_find_inlinefunc(rt_die, addr, &die_mem)) {
927 /* Call-site check */
928 inf = die_get_call_file(&die_mem);
929 if ((inf && !strcmp(inf, decf)) &&
930 die_get_call_lineno(&die_mem) == lineno)
933 dwarf_decl_line(&die_mem, &inl);
935 decf != die_get_decl_file(&die_mem))
940 /* Get source line */
941 fname = dwarf_linesrc(line, NULL, NULL);
943 ret = callback(fname, lineno, addr, data);
949 * Dwarf lines doesn't include function declarations and inlined
950 * subroutines. We have to check functions list or given function.
952 if (rt_die != cu_die)
954 * Don't need walk inlined functions recursively, because
955 * inner inlined functions don't have the lines of the
956 * specified function.
958 ret = __die_walk_funclines(rt_die, false, callback, data);
960 struct __line_walk_param param = {
961 .callback = callback,
965 dwarf_getfuncs(cu_die, __die_walk_culines_cb, ¶m, 0);
972 struct __find_variable_param {
977 static int __die_find_variable_cb(Dwarf_Die *die_mem, void *data)
979 struct __find_variable_param *fvp = data;
980 Dwarf_Attribute attr;
983 tag = dwarf_tag(die_mem);
984 if ((tag == DW_TAG_formal_parameter ||
985 tag == DW_TAG_variable) &&
986 die_compare_name(die_mem, fvp->name) &&
988 * Does the DIE have location information or const value
989 * or external instance?
991 (dwarf_attr(die_mem, DW_AT_external, &attr) ||
992 dwarf_attr(die_mem, DW_AT_location, &attr) ||
993 dwarf_attr(die_mem, DW_AT_const_value, &attr)))
994 return DIE_FIND_CB_END;
995 if (dwarf_haspc(die_mem, fvp->addr))
996 return DIE_FIND_CB_CONTINUE;
998 return DIE_FIND_CB_SIBLING;
1002 * die_find_variable_at - Find a given name variable at given address
1003 * @sp_die: a function DIE
1004 * @name: variable name
1006 * @die_mem: a buffer for result DIE
1008 * Find a variable DIE called @name at @addr in @sp_die.
1010 Dwarf_Die *die_find_variable_at(Dwarf_Die *sp_die, const char *name,
1011 Dwarf_Addr addr, Dwarf_Die *die_mem)
1013 struct __find_variable_param fvp = { .name = name, .addr = addr};
1015 return die_find_child(sp_die, __die_find_variable_cb, (void *)&fvp,
1019 static int __die_find_member_cb(Dwarf_Die *die_mem, void *data)
1021 const char *name = data;
1023 if (dwarf_tag(die_mem) == DW_TAG_member) {
1024 if (die_compare_name(die_mem, name))
1025 return DIE_FIND_CB_END;
1026 else if (!dwarf_diename(die_mem)) { /* Unnamed structure */
1027 Dwarf_Die type_die, tmp_die;
1028 if (die_get_type(die_mem, &type_die) &&
1029 die_find_member(&type_die, name, &tmp_die))
1030 return DIE_FIND_CB_END;
1033 return DIE_FIND_CB_SIBLING;
1037 * die_find_member - Find a given name member in a data structure
1038 * @st_die: a data structure type DIE
1039 * @name: member name
1040 * @die_mem: a buffer for result DIE
1042 * Find a member DIE called @name in @st_die.
1044 Dwarf_Die *die_find_member(Dwarf_Die *st_die, const char *name,
1047 return die_find_child(st_die, __die_find_member_cb, (void *)name,
1052 * die_get_typename - Get the name of given variable DIE
1053 * @vr_die: a variable DIE
1054 * @buf: a strbuf for result type name
1056 * Get the name of @vr_die and stores it to @buf. Return 0 if succeeded.
1057 * and Return -ENOENT if failed to find type name.
1058 * Note that the result will stores typedef name if possible, and stores
1059 * "*(function_type)" if the type is a function pointer.
1061 int die_get_typename(Dwarf_Die *vr_die, struct strbuf *buf)
1065 const char *tmp = "";
1067 if (__die_get_real_type(vr_die, &type) == NULL)
1070 tag = dwarf_tag(&type);
1071 if (tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)
1073 else if (tag == DW_TAG_subroutine_type) {
1074 /* Function pointer */
1075 return strbuf_add(buf, "(function_type)", 15);
1077 const char *name = dwarf_diename(&type);
1079 if (tag == DW_TAG_union_type)
1081 else if (tag == DW_TAG_structure_type)
1083 else if (tag == DW_TAG_enumeration_type)
1085 else if (name == NULL)
1087 /* Write a base name */
1088 return strbuf_addf(buf, "%s%s", tmp, name ?: "");
1090 ret = die_get_typename(&type, buf);
1091 return ret ? ret : strbuf_addstr(buf, tmp);
1095 * die_get_varname - Get the name and type of given variable DIE
1096 * @vr_die: a variable DIE
1097 * @buf: a strbuf for type and variable name
1099 * Get the name and type of @vr_die and stores it in @buf as "type\tname".
1101 int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf)
1105 ret = die_get_typename(vr_die, buf);
1107 pr_debug("Failed to get type, make it unknown.\n");
1108 ret = strbuf_add(buf, "(unknown_type)", 14);
1111 return ret < 0 ? ret : strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
1114 #ifdef HAVE_DWARF_GETLOCATIONS_SUPPORT
1116 * die_get_var_innermost_scope - Get innermost scope range of given variable DIE
1117 * @sp_die: a subprogram DIE
1118 * @vr_die: a variable DIE
1119 * @buf: a strbuf for variable byte offset range
1121 * Get the innermost scope range of @vr_die and stores it in @buf as
1122 * "@<function_name+[NN-NN,NN-NN]>".
1124 static int die_get_var_innermost_scope(Dwarf_Die *sp_die, Dwarf_Die *vr_die,
1131 Dwarf_Addr start, end;
1137 ret = die_entrypc(sp_die, &entry);
1141 name = dwarf_diename(sp_die);
1145 count = dwarf_getscopes_die(vr_die, &scopes);
1147 /* (*SCOPES)[1] is the DIE for the scope containing that scope */
1153 while ((offset = dwarf_ranges(&scopes[1], offset, &base,
1154 &start, &end)) > 0) {
1159 ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
1163 ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
1171 ret = strbuf_add(buf, "]>", 2);
1179 * die_get_var_range - Get byte offset range of given variable DIE
1180 * @sp_die: a subprogram DIE
1181 * @vr_die: a variable DIE
1182 * @buf: a strbuf for type and variable name and byte offset range
1184 * Get the byte offset range of @vr_die and stores it in @buf as
1185 * "@<function_name+[NN-NN,NN-NN]>".
1187 int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf)
1191 Dwarf_Addr start, end;
1196 Dwarf_Attribute attr;
1200 ret = die_entrypc(sp_die, &entry);
1204 name = dwarf_diename(sp_die);
1208 if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL)
1211 while ((offset = dwarf_getlocations(&attr, offset, &base,
1212 &start, &end, &op, &nops)) > 0) {
1214 /* Single Location Descriptions */
1215 ret = die_get_var_innermost_scope(sp_die, vr_die, buf);
1219 /* Location Lists */
1223 ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
1227 ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
1235 ret = strbuf_add(buf, "]>", 2);
1240 int die_get_var_range(Dwarf_Die *sp_die __maybe_unused,
1241 Dwarf_Die *vr_die __maybe_unused,
1242 struct strbuf *buf __maybe_unused)
1249 * die_has_loclist - Check if DW_AT_location of @vr_die is a location list
1250 * @vr_die: a variable DIE
1252 static bool die_has_loclist(Dwarf_Die *vr_die)
1254 Dwarf_Attribute loc;
1255 int tag = dwarf_tag(vr_die);
1257 if (tag != DW_TAG_formal_parameter &&
1258 tag != DW_TAG_variable)
1261 return (dwarf_attr_integrate(vr_die, DW_AT_location, &loc) &&
1262 dwarf_whatform(&loc) == DW_FORM_sec_offset);
1266 * die_is_optimized_target - Check if target program is compiled with
1270 * For any object in given CU whose DW_AT_location is a location list,
1271 * target program is compiled with optimization. This is applicable to
1274 bool die_is_optimized_target(Dwarf_Die *cu_die)
1278 if (die_has_loclist(cu_die))
1281 if (!dwarf_child(cu_die, &tmp_die) &&
1282 die_is_optimized_target(&tmp_die))
1285 if (!dwarf_siblingof(cu_die, &tmp_die) &&
1286 die_is_optimized_target(&tmp_die))
1293 * die_search_idx - Search index of given line address
1294 * @lines: Line records of single CU
1295 * @nr_lines: Number of @lines
1296 * @addr: address we are looking for
1297 * @idx: index to be set by this function (return value)
1299 * Search for @addr by looping over every lines of CU. If address
1300 * matches, set index of that line in @idx. Note that single source
1301 * line can have multiple line records. i.e. single source line can
1302 * have multiple index.
1304 static bool die_search_idx(Dwarf_Lines *lines, unsigned long nr_lines,
1305 Dwarf_Addr addr, unsigned long *idx)
1310 for (i = 0; i < nr_lines; i++) {
1311 if (dwarf_lineaddr(dwarf_onesrcline(lines, i), &tmp))
1323 * die_get_postprologue_addr - Search next address after function prologue
1324 * @entrypc_idx: entrypc index
1325 * @lines: Line records of single CU
1326 * @nr_lines: Number of @lines
1327 * @hignpc: high PC address of function
1328 * @postprologue_addr: Next address after function prologue (return value)
1330 * Look for prologue-end marker. If there is no explicit marker, return
1331 * address of next line record or next source line.
1333 static bool die_get_postprologue_addr(unsigned long entrypc_idx,
1335 unsigned long nr_lines,
1337 Dwarf_Addr *postprologue_addr)
1340 int entrypc_lno, lno;
1345 /* entrypc_lno is actual source line number */
1346 line = dwarf_onesrcline(lines, entrypc_idx);
1347 if (dwarf_lineno(line, &entrypc_lno))
1350 for (i = entrypc_idx; i < nr_lines; i++) {
1351 line = dwarf_onesrcline(lines, i);
1353 if (dwarf_lineaddr(line, &addr) ||
1354 dwarf_lineno(line, &lno) ||
1355 dwarf_lineprologueend(line, &p_end))
1358 /* highpc is exclusive. [entrypc,highpc) */
1362 /* clang supports prologue-end marker */
1366 /* Actual next line in source */
1367 if (lno != entrypc_lno)
1371 * Single source line can have multiple line records.
1373 * void foo() { printf("hello\n"); }
1374 * contains two line records. One points to declaration and
1375 * other points to printf() line. Variable 'lno' won't get
1376 * incremented in this case but 'i' will.
1378 if (i != entrypc_idx)
1382 dwarf_lineaddr(line, postprologue_addr);
1383 if (*postprologue_addr >= highpc)
1384 dwarf_lineaddr(dwarf_onesrcline(lines, i - 1),
1391 * die_skip_prologue - Use next address after prologue as probe location
1392 * @sp_die: a subprogram DIE
1394 * @entrypc: entrypc of the function
1396 * Function prologue prepares stack and registers before executing function
1397 * logic. When target program is compiled without optimization, function
1398 * parameter information is only valid after prologue. When we probe entrypc
1399 * of the function, and try to record function parameter, it contains
1402 void die_skip_prologue(Dwarf_Die *sp_die, Dwarf_Die *cu_die,
1403 Dwarf_Addr *entrypc)
1405 size_t nr_lines = 0;
1406 unsigned long entrypc_idx = 0;
1407 Dwarf_Lines *lines = NULL;
1408 Dwarf_Addr postprologue_addr;
1411 if (dwarf_highpc(sp_die, &highpc))
1414 if (dwarf_getsrclines(cu_die, &lines, &nr_lines))
1417 if (!die_search_idx(lines, nr_lines, *entrypc, &entrypc_idx))
1420 if (!die_get_postprologue_addr(entrypc_idx, lines, nr_lines,
1421 highpc, &postprologue_addr))
1424 *entrypc = postprologue_addr;