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
47  * cu_get_comp_dir - Get the path of compilation directory
66 	Dwarf_Lines *lines;  in cu_getsrc_die()  local
71 	if (dwarf_getsrclines(cu_die, &lines, &nlines) != 0 ||  in cu_getsrc_die()
75 	/* Lines are sorted by address, use binary search */  in cu_getsrc_die()
76 	l = 0; u = nlines - 1;  in cu_getsrc_die()
78 		n = u - (u - l) / 2;  in cu_getsrc_die()
79 		line = dwarf_onesrcline(lines, n);  in cu_getsrc_die()
83 			u = n - 1;  in cu_getsrc_die()
89 		line = dwarf_onesrcline(lines, --l);  in cu_getsrc_die()
96 		line = dwarf_onesrcline(lines, l++);  in cu_getsrc_die()
108  * cu_find_lineinfo - Get a line number and file name for given address
140 	return (*lineno && *fname) ? *lineno : -ENOENT;  in cu_find_lineinfo()
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
150  * @data: A user data
153  * should be subprogram or inlined-subroutines.
156 		    int (*callback)(Dwarf_Die *, void *), void *data)  in cu_walk_functions_at()  argument
160 	int ret = -ENOENT;  in cu_walk_functions_at()
167 		ret = callback(sc_die, data);  in cu_walk_functions_at()
177  * die_get_linkage_name - Get the linkage name of the object
193  * die_compare_name - Compare diename and tname
208  * die_match_name - Match diename/linkage name and glob
231  * die_get_call_lineno - Get callsite line number of inline-function instance
234  * Get call-site line number of @in_die. This means from where the inline
243 		return -ENOENT;  in die_get_call_lineno()
250  * die_get_type - Get type DIE
287  * die_get_real_type - Get a type die, but skip qualifiers and typedef
313 		return -ENOENT;  in die_get_attr_udata()
319  * die_is_signed_type - Check whether a type DIE is signed or not
337  * die_is_func_def - Ensure that this DIE is a subprogram and definition
368  * die_entrypc - Returns entry PC (the lowest address) of a DIE
382 		return -EINVAL;  in die_entrypc()
392 		return -ENOENT;  in die_entrypc()
394 	return dwarf_ranges(dw_die, 0, &base, addr, &end) < 0 ? -ENOENT : 0;  in die_entrypc()
398  * die_is_func_instance - Ensure that this DIE is an instance of a subprogram
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
436 		return -ENOENT;  in die_get_data_member_location()
442 			return -ENOENT;  in die_get_data_member_location()
447 			return -ENOTSUP;  in die_get_data_member_location()
462 		return -ENOENT;  in die_get_call_fileno()
473 		return -ENOENT;  in die_get_decl_fileno()
492  * die_get_call_file - Get callsite file name of inlined function instance
495  * Get call-site file name of @in_die. This means from which file the inline
504  * die_get_decl_file - Find the declared file name of this DIE
518  * die_find_child - Generic DIE search function in DIE tree
521  * @data: a user data passed to the callback function
534 			  void *data, Dwarf_Die *die_mem)  in die_find_child()  argument
544 		ret = callback(die_mem, data);  in die_find_child()
549 		    die_find_child(die_mem, callback, data, &child_die)) {  in die_find_child()
564 static int __die_search_func_tail_cb(Dwarf_Die *fn_die, void *data)  in __die_search_func_tail_cb()  argument
566 	struct __addr_die_search_param *ad = data;  in __die_search_func_tail_cb()
571 	    addr == ad->addr) {  in __die_search_func_tail_cb()
572 		memcpy(ad->die_mem, fn_die, sizeof(Dwarf_Die));  in __die_search_func_tail_cb()
579  * die_find_tailfunc - Search for a non-inlined function with tail call at
585  * Search for a non-inlined function DIE with tail call at @addr. Stores the
601 /* die_find callback for non-inlined function search */
602 static int __die_search_func_cb(Dwarf_Die *fn_die, void *data)  in __die_search_func_cb()  argument
604 	struct __addr_die_search_param *ad = data;  in __die_search_func_cb()
611 	    dwarf_haspc(fn_die, ad->addr)) {  in __die_search_func_cb()
612 		memcpy(ad->die_mem, fn_die, sizeof(Dwarf_Die));  in __die_search_func_cb()
619  * die_find_realfunc - Search a non-inlined function at given address
624  * Search a non-inlined function DIE which includes @addr. Stores the
641 static int __die_find_inline_cb(Dwarf_Die *die_mem, void *data)  in __die_find_inline_cb()  argument
643 	Dwarf_Addr *addr = data;  in __die_find_inline_cb()
653  * die_find_top_inlinefunc - Search the top inlined function at given address
670  * die_find_inlinefunc - Search an inlined function at given address
702 	void    *data;  member
706 static int __die_walk_instances_cb(Dwarf_Die *inst, void *data)  in __die_walk_instances_cb()  argument
708 	struct __instance_walk_param *iwp = data;  in __die_walk_instances_cb()
723 	if (origin == NULL || origin->addr != iwp->addr)  in __die_walk_instances_cb()
736 	iwp->retval = iwp->callback(inst, iwp->data);  in __die_walk_instances_cb()
738 	return (iwp->retval) ? DIE_FIND_CB_END : DIE_FIND_CB_CONTINUE;  in __die_walk_instances_cb()
742  * die_walk_instances - Walk on instances of given DIE
745  * @data: user data
749  * non-zero value, or -ENOENT if there is no instance.
752 		       void *data)  in die_walk_instances()  argument
757 		.addr = or_die->addr,  in die_walk_instances()
759 		.data = data,  in die_walk_instances()
760 		.retval = -ENOENT,  in die_walk_instances()
764 		return -ENOENT;  in die_walk_instances()
775 	void *data;  member
779 static int __die_walk_funclines_cb(Dwarf_Die *in_die, void *data)  in __die_walk_funclines_cb()  argument
781 	struct __line_walk_param *lw = data;  in __die_walk_funclines_cb()
790 			lw->retval = lw->callback(fname, lineno, addr, lw->data);  in __die_walk_funclines_cb()
791 			if (lw->retval != 0)  in __die_walk_funclines_cb()
794 		if (!lw->recursive)  in __die_walk_funclines_cb()
801 			lw->retval = lw->callback(fname, lineno, addr, lw->data);  in __die_walk_funclines_cb()
802 			if (lw->retval != 0)  in __die_walk_funclines_cb()
807 	/* Continue to search nested inlined function call-sites */  in __die_walk_funclines_cb()
811 /* Walk on lines of blocks included in given DIE */
813 				line_walk_callback_t callback, void *data)  in __die_walk_funclines()  argument
818 		.data = data,  in __die_walk_funclines()
830 		lw.retval = callback(fname, lineno, addr, data);  in __die_walk_funclines()
839 static int __die_walk_culines_cb(Dwarf_Die *sp_die, void *data)  in __die_walk_culines_cb()  argument
841 	struct __line_walk_param *lw = data;  in __die_walk_culines_cb()
847 	lw->retval = __die_walk_funclines(sp_die, true, lw->callback, lw->data);  in __die_walk_culines_cb()
848 	if (lw->retval != 0)  in __die_walk_culines_cb()
855  * die_walk_lines - Walk on lines inside given DIE
858  * @data: user data
860  * Walk on all lines inside given @rt_die and call @callback on each line.
861  * If the @rt_die is a function, walk only on the lines inside the function,
864  * and inline call-site.
866 int die_walk_lines(Dwarf_Die *rt_die, line_walk_callback_t callback, void *data)  in die_walk_lines()  argument
868 	Dwarf_Lines *lines;  in die_walk_lines()  local
886 			return -EINVAL;  in die_walk_lines()
892 		return -EINVAL;  in die_walk_lines()
895 	/* Get lines list in the CU */  in die_walk_lines()
896 	if (dwarf_getsrclines(cu_die, &lines, &nlines) != 0) {  in die_walk_lines()
897 		pr_debug2("Failed to get source lines on this CU.\n");  in die_walk_lines()
898 		return -ENOENT;  in die_walk_lines()
900 	pr_debug2("Get %zd lines from this CU\n", nlines);  in die_walk_lines()
902 	/* Walk on the lines on lines list */  in die_walk_lines()
904 		line = dwarf_onesrcline(lines, i);  in die_walk_lines()
912 		/* Skip end-of-sequence */  in die_walk_lines()
915 		/* Skip Non statement line-info */  in die_walk_lines()
918 		/* Filter lines based on address */  in die_walk_lines()
929 				/* Call-site check */  in die_walk_lines()
945 		ret = callback(fname, lineno, addr, data);  in die_walk_lines()
951 	 * Dwarf lines doesn't include function declarations and inlined  in die_walk_lines()
957 		 * inner inlined functions don't have the lines of the  in die_walk_lines()
960 		ret = __die_walk_funclines(rt_die, false, callback, data);  in die_walk_lines()
964 			.data = data,  in die_walk_lines()
979 static int __die_find_variable_cb(Dwarf_Die *die_mem, void *data)  in __die_find_variable_cb()  argument
981 	struct __find_variable_param *fvp = data;  in __die_find_variable_cb()
988 	    die_compare_name(die_mem, fvp->name) &&  in __die_find_variable_cb()
997 	if (dwarf_haspc(die_mem, fvp->addr))  in __die_find_variable_cb()
1004  * die_find_variable_at - Find a given name variable at given address
1021 static int __die_find_member_cb(Dwarf_Die *die_mem, void *data)  in __die_find_member_cb()  argument
1023 	const char *name = data;  in __die_find_member_cb()
1039  * die_find_member - Find a given name member in a data structure
1040  * @st_die: a data structure type DIE
1054  * die_get_typename - Get the name of given variable DIE
1059  * and Return -ENOENT if failed to find type name.
1070 		return -ENOENT;  in die_get_typename()
1088 			return -ENOENT;  in die_get_typename()
1097  * die_get_varname - Get the name and type of given variable DIE
1118  * die_get_var_innermost_scope - Get innermost scope range of given variable DIE
1124  * "@<function_name+[NN-NN,NN-NN]>".
1145 		return -ENOENT;  in die_get_var_innermost_scope()
1151 		ret = -EINVAL;  in die_get_var_innermost_scope()
1157 		start -= entry;  in die_get_var_innermost_scope()
1158 		end -= entry;  in die_get_var_innermost_scope()
1161 			ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,  in die_get_var_innermost_scope()
1165 			ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,  in die_get_var_innermost_scope()
1181  * die_get_var_range - Get byte offset range of given variable DIE
1187  * "@<function_name+[NN-NN,NN-NN]>".
1208 		return -ENOENT;  in die_get_var_range()
1211 		return -EINVAL;  in die_get_var_range()
1222 		start -= entry;  in die_get_var_range()
1223 		end -= entry;  in die_get_var_range()
1225 			ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,  in die_get_var_range()
1229 			ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,  in die_get_var_range()
1246 	return -ENOTSUP;  in die_get_var_range()
1251  * die_has_loclist - Check if DW_AT_location of @vr_die is a location list
1268  * die_is_optimized_target - Check if target program is compiled with
1295  * die_search_idx - Search index of given line address
1296  * @lines: Line records of single CU
1297  * @nr_lines: Number of @lines
1301  * Search for @addr by looping over every lines of CU. If address
1306 static bool die_search_idx(Dwarf_Lines *lines, unsigned long nr_lines,  in die_search_idx()  argument
1313 		if (dwarf_lineaddr(dwarf_onesrcline(lines, i), &tmp))  in die_search_idx()
1325  * die_get_postprologue_addr - Search next address after function prologue
1327  * @lines: Line records of single CU
1328  * @nr_lines: Number of @lines
1332  * Look for prologue-end marker. If there is no explicit marker, return
1336 				      Dwarf_Lines *lines,  in die_get_postprologue_addr()  argument
1348 	line = dwarf_onesrcline(lines, entrypc_idx);  in die_get_postprologue_addr()
1353 		line = dwarf_onesrcline(lines, i);  in die_get_postprologue_addr()
1364 		/* clang supports prologue-end marker */  in die_get_postprologue_addr()
1386 		dwarf_lineaddr(dwarf_onesrcline(lines, i - 1),  in die_get_postprologue_addr()
1393  * die_skip_prologue - Use next address after prologue as probe location
1409 	Dwarf_Lines *lines = NULL;  in die_skip_prologue()  local
1416 	if (dwarf_getsrclines(cu_die, &lines, &nr_lines))  in die_skip_prologue()
1419 	if (!die_search_idx(lines, nr_lines, *entrypc, &entrypc_idx))  in die_skip_prologue()
1422 	if (!die_get_postprologue_addr(entrypc_idx, lines, nr_lines,  in die_skip_prologue()