xref: /trueos/lib/libdwarf/dwarf_func.c (revision 8fe640108653f13042f1b15213769e338aa524f6)
1 /*-
2  * Copyright (c) 2008-2009, 2011, Juniper Networks, Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
15  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
16  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE
18  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
19  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
20  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
21  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
22  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
23  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
24  * THE POSSIBILITY OF SUCH DAMAGE.
25  *
26  *	JNPR: dwarf_func.c 336441 2009-10-17 09:19:54Z deo
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <stdlib.h>
33 #include <string.h>
34 #include <libdwarf.h>
35 #include <_libdwarf.h>
36 
37 static void
dwarf_add_function(Dwarf_Debug dbg,Dwarf_Func func)38 dwarf_add_function(Dwarf_Debug dbg, Dwarf_Func func)
39 {
40 
41 	STAILQ_INSERT_TAIL(&dbg->dbg_func, func, func_next);
42 }
43 
44 int
dwarf_function_get_addr_range(Dwarf_Func f,Dwarf_Addr * low_pc,Dwarf_Addr * high_pc)45 dwarf_function_get_addr_range(Dwarf_Func f, Dwarf_Addr *low_pc,
46     Dwarf_Addr *high_pc)
47 {
48 
49 	*low_pc = f->func_low_pc;
50 	*high_pc = f->func_high_pc;
51 	return 0;
52 }
53 
54 int
dwarf_inlined_function_get_addr_range(Dwarf_Inlined_Func f,Dwarf_Addr * low_pc,Dwarf_Addr * high_pc)55 dwarf_inlined_function_get_addr_range(Dwarf_Inlined_Func f, Dwarf_Addr *low_pc,
56     Dwarf_Addr *high_pc)
57 {
58 
59 	*low_pc = f->ifunc_low_pc;
60 	*high_pc = f->ifunc_high_pc;
61 	return 0;
62 }
63 
64 int
dwarf_function_is_inlined(Dwarf_Func f)65 dwarf_function_is_inlined(Dwarf_Func f)
66 {
67 
68 	if (f->func_is_inlined == DW_INL_inlined ||
69 	    f->func_is_inlined == DW_INL_declared_inlined)
70 		return 1;
71 	else
72 		return 0;
73 }
74 
75 Dwarf_Func
dwarf_find_function_by_name(Dwarf_Debug dbg,const char * name)76 dwarf_find_function_by_name(Dwarf_Debug dbg, const char *name)
77 {
78 	/* XXX: replace with a fast version */
79 
80 	Dwarf_Func func;
81 	STAILQ_FOREACH(func, &dbg->dbg_func, func_next) {
82 		if (strcmp(name, func->func_name) == 0)
83 			return func;
84 	}
85 	return NULL;
86 }
87 
88 Dwarf_Func
dwarf_find_function_by_offset(Dwarf_Debug dbg,Dwarf_Off off)89 dwarf_find_function_by_offset(Dwarf_Debug dbg, Dwarf_Off off)
90 {
91 
92 	Dwarf_Func func;
93 	Dwarf_Die die;
94 	/* printf("look for %llx\n", off); */
95 	STAILQ_FOREACH(func, &dbg->dbg_func, func_next) {
96 		die = func->func_die;
97 		if ((off_t)die->die_offset == off) {
98 			return func;
99 		}
100 	}
101 	return NULL;
102 }
103 
104 void
dwarf_build_function_table(Dwarf_Debug dbg)105 dwarf_build_function_table(Dwarf_Debug dbg)
106 {
107 	Dwarf_CU cu;
108 	Dwarf_AttrValue av;
109 	Dwarf_Die die, origin_die;
110 	Dwarf_Func func, origin_func;
111 	Dwarf_Inlined_Func ifunc;
112 	unsigned long long offset;
113 	const char *name;
114 	Dwarf_Error error;
115 
116 	/*
117 	 * find out all the functions
118 	 */
119 	STAILQ_FOREACH(cu, &dbg->dbg_cu, cu_next) {
120 		STAILQ_FOREACH(die, &cu->cu_die, die_next) {
121 			if (die->die_a->a_tag == DW_TAG_subprogram) {
122 				/*
123 				 * Some function has multiple entries, i.e.
124 				 * if a function is inlined, it has many
125 				 * abstract/concrete instances, the abstract
126 				 * instances are with DW_TAG_subprogram.
127 				 */
128 				dwarf_attrval_string(die, DW_AT_name, &name,
129 				    &error);
130 				func = dwarf_find_function_by_name(dbg, name);
131 				if (func == NULL) {
132 					func = malloc(
133 					    sizeof(struct _Dwarf_Func));
134 					DWARF_ASSERT(func);
135 
136 					func->func_die = die;
137 					func->func_name = name;
138 					STAILQ_INIT(
139 					    &func->func_inlined_instances);
140 
141 					dwarf_add_function(dbg, func);
142 					STAILQ_FOREACH(av, &die->die_attrval,
143 					    av_next) {
144 						switch (av->av_attrib) {
145 						case DW_AT_low_pc:
146 							func->func_low_pc =
147 							    av->u[0].u64;
148 							break;
149 						case DW_AT_high_pc:
150 							func->func_high_pc =
151 							    av->u[0].u64;
152 							break;
153 						case DW_AT_inline:
154 							func->func_is_inlined =
155 							    av->u[0].u64;
156 							break;
157 						}
158 					}
159 				}
160 			}
161 		}
162 	}
163 
164 	/*
165 	 * Now check the concrete inlined instances.
166 	 */
167 	STAILQ_FOREACH(cu, &dbg->dbg_cu, cu_next) {
168 		STAILQ_FOREACH(die, &cu->cu_die, die_next) {
169 			if (die->die_a->a_tag == DW_TAG_inlined_subroutine) {
170 				ifunc = malloc(
171 				    sizeof(struct _Dwarf_Inlined_Func));
172 				DWARF_ASSERT(ifunc);
173 				STAILQ_FOREACH(av, &die->die_attrval, av_next) {
174 					switch (av->av_attrib) {
175 					case DW_AT_abstract_origin:
176 						offset = av->u[0].u64 +
177 						    die->die_cu->cu_offset;
178 						origin_die = dwarf_die_find(
179 							die, offset);
180 						DWARF_ASSERT(origin_die != 0);
181 
182 						/*
183 						 * the abstract origin must
184 						 * have been merged with
185 						 * another die
186 						 */
187 						dwarf_attrval_string(
188 						    origin_die, DW_AT_name,
189 						    &name, &error);
190 						origin_func =
191 						    dwarf_find_function_by_name
192 						    (dbg, name);
193 						DWARF_ASSERT(origin_func != 0);
194 
195 						STAILQ_INSERT_TAIL(
196 						    &origin_func->
197 						    func_inlined_instances,
198 						    ifunc, ifunc_next);
199 
200 						break;
201 					case DW_AT_low_pc:
202 						ifunc->ifunc_low_pc =
203 						    av->u[0].u64;
204 						break;
205 					case DW_AT_high_pc:
206 						ifunc->ifunc_high_pc =
207 						    av->u[0].u64;
208 						break;
209 					}
210 				}
211 			}
212 		}
213 	}
214 }
215 
216 void
dwarf_function_iterate_inlined_instance(Dwarf_Func func,Dwarf_Inlined_Callback f,void * data)217 dwarf_function_iterate_inlined_instance(Dwarf_Func func,
218     Dwarf_Inlined_Callback f, void *data)
219 {
220 	Dwarf_Inlined_Func ifunc;
221 
222 	if (!dwarf_function_is_inlined(func))
223 		return;
224 	STAILQ_FOREACH(ifunc, &func->func_inlined_instances, ifunc_next) {
225 		f(ifunc, data);
226 	}
227 }
228