1 //===-- DWARFDebugInfoEntry.cpp --------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "DWARFDebugInfoEntry.h"
11 #include "DWARFCompileUnit.h"
12 #include "DWARFContext.h"
13 #include "DWARFDebugAbbrev.h"
14 #include "DWARFFormValue.h"
15 #include "llvm/Support/Dwarf.h"
16 #include "llvm/Support/Format.h"
17 #include "llvm/Support/raw_ostream.h"
18 using namespace llvm;
19 using namespace dwarf;
20
dump(raw_ostream & OS,const DWARFCompileUnit * cu,unsigned recurseDepth,unsigned indent) const21 void DWARFDebugInfoEntryMinimal::dump(raw_ostream &OS,
22 const DWARFCompileUnit *cu,
23 unsigned recurseDepth,
24 unsigned indent) const {
25 DataExtractor debug_info_data = cu->getDebugInfoExtractor();
26 uint32_t offset = Offset;
27
28 if (debug_info_data.isValidOffset(offset)) {
29 uint64_t abbrCode = debug_info_data.getULEB128(&offset);
30
31 OS << format("\n0x%8.8x: ", Offset);
32 if (abbrCode) {
33 if (AbbrevDecl) {
34 const char *tagString = TagString(getTag());
35 if (tagString)
36 OS.indent(indent) << tagString;
37 else
38 OS.indent(indent) << format("DW_TAG_Unknown_%x", getTag());
39 OS << format(" [%u] %c\n", abbrCode,
40 AbbrevDecl->hasChildren() ? '*' : ' ');
41
42 // Dump all data in the .debug_info for the attributes
43 const uint32_t numAttributes = AbbrevDecl->getNumAttributes();
44 for (uint32_t i = 0; i != numAttributes; ++i) {
45 uint16_t attr = AbbrevDecl->getAttrByIndex(i);
46 uint16_t form = AbbrevDecl->getFormByIndex(i);
47 dumpAttribute(OS, cu, &offset, attr, form, indent);
48 }
49
50 const DWARFDebugInfoEntryMinimal *child = getFirstChild();
51 if (recurseDepth > 0 && child) {
52 while (child) {
53 child->dump(OS, cu, recurseDepth-1, indent+2);
54 child = child->getSibling();
55 }
56 }
57 } else {
58 OS << "Abbreviation code not found in 'debug_abbrev' class for code: "
59 << abbrCode << '\n';
60 }
61 } else {
62 OS.indent(indent) << "NULL\n";
63 }
64 }
65 }
66
dumpAttribute(raw_ostream & OS,const DWARFCompileUnit * cu,uint32_t * offset_ptr,uint16_t attr,uint16_t form,unsigned indent) const67 void DWARFDebugInfoEntryMinimal::dumpAttribute(raw_ostream &OS,
68 const DWARFCompileUnit *cu,
69 uint32_t* offset_ptr,
70 uint16_t attr,
71 uint16_t form,
72 unsigned indent) const {
73 OS << format("0x%8.8x: ", *offset_ptr);
74 OS.indent(indent+2);
75 const char *attrString = AttributeString(attr);
76 if (attrString)
77 OS << attrString;
78 else
79 OS << format("DW_AT_Unknown_%x", attr);
80 const char *formString = FormEncodingString(form);
81 if (formString)
82 OS << " [" << formString << ']';
83 else
84 OS << format(" [DW_FORM_Unknown_%x]", form);
85
86 DWARFFormValue formValue(form);
87
88 if (!formValue.extractValue(cu->getDebugInfoExtractor(), offset_ptr, cu))
89 return;
90
91 OS << "\t(";
92 formValue.dump(OS, cu);
93 OS << ")\n";
94 }
95
extractFast(const DWARFCompileUnit * cu,const uint8_t * fixed_form_sizes,uint32_t * offset_ptr)96 bool DWARFDebugInfoEntryMinimal::extractFast(const DWARFCompileUnit *cu,
97 const uint8_t *fixed_form_sizes,
98 uint32_t *offset_ptr) {
99 Offset = *offset_ptr;
100
101 DataExtractor debug_info_data = cu->getDebugInfoExtractor();
102 uint64_t abbrCode = debug_info_data.getULEB128(offset_ptr);
103
104 assert (fixed_form_sizes); // For best performance this should be specified!
105
106 if (abbrCode) {
107 uint32_t offset = *offset_ptr;
108
109 AbbrevDecl = cu->getAbbreviations()->getAbbreviationDeclaration(abbrCode);
110
111 // Skip all data in the .debug_info for the attributes
112 const uint32_t numAttributes = AbbrevDecl->getNumAttributes();
113 uint32_t i;
114 uint16_t form;
115 for (i=0; i<numAttributes; ++i) {
116 form = AbbrevDecl->getFormByIndex(i);
117
118 const uint8_t fixed_skip_size = fixed_form_sizes[form];
119 if (fixed_skip_size)
120 offset += fixed_skip_size;
121 else {
122 bool form_is_indirect = false;
123 do {
124 form_is_indirect = false;
125 uint32_t form_size = 0;
126 switch (form) {
127 // Blocks if inlined data that have a length field and the data bytes
128 // inlined in the .debug_info.
129 case DW_FORM_block:
130 form_size = debug_info_data.getULEB128(&offset);
131 break;
132 case DW_FORM_block1:
133 form_size = debug_info_data.getU8(&offset);
134 break;
135 case DW_FORM_block2:
136 form_size = debug_info_data.getU16(&offset);
137 break;
138 case DW_FORM_block4:
139 form_size = debug_info_data.getU32(&offset);
140 break;
141
142 // Inlined NULL terminated C-strings
143 case DW_FORM_string:
144 debug_info_data.getCStr(&offset);
145 break;
146
147 // Compile unit address sized values
148 case DW_FORM_addr:
149 case DW_FORM_ref_addr:
150 form_size = cu->getAddressByteSize();
151 break;
152
153 // 1 byte values
154 case DW_FORM_data1:
155 case DW_FORM_flag:
156 case DW_FORM_ref1:
157 form_size = 1;
158 break;
159
160 // 2 byte values
161 case DW_FORM_data2:
162 case DW_FORM_ref2:
163 form_size = 2;
164 break;
165
166 // 4 byte values
167 case DW_FORM_strp:
168 case DW_FORM_data4:
169 case DW_FORM_ref4:
170 form_size = 4;
171 break;
172
173 // 8 byte values
174 case DW_FORM_data8:
175 case DW_FORM_ref8:
176 form_size = 8;
177 break;
178
179 // signed or unsigned LEB 128 values
180 case DW_FORM_sdata:
181 case DW_FORM_udata:
182 case DW_FORM_ref_udata:
183 debug_info_data.getULEB128(&offset);
184 break;
185
186 case DW_FORM_indirect:
187 form_is_indirect = true;
188 form = debug_info_data.getULEB128(&offset);
189 break;
190
191 default:
192 *offset_ptr = Offset;
193 return false;
194 }
195 offset += form_size;
196
197 } while (form_is_indirect);
198 }
199 }
200 *offset_ptr = offset;
201 return true;
202 } else {
203 AbbrevDecl = NULL;
204 return true; // NULL debug tag entry
205 }
206
207 return false;
208 }
209
210 bool
extract(const DWARFCompileUnit * cu,uint32_t * offset_ptr)211 DWARFDebugInfoEntryMinimal::extract(const DWARFCompileUnit *cu,
212 uint32_t *offset_ptr) {
213 DataExtractor debug_info_data = cu->getDebugInfoExtractor();
214 const uint32_t cu_end_offset = cu->getNextCompileUnitOffset();
215 const uint8_t cu_addr_size = cu->getAddressByteSize();
216 uint32_t offset = *offset_ptr;
217 if ((offset < cu_end_offset) && debug_info_data.isValidOffset(offset)) {
218 Offset = offset;
219
220 uint64_t abbrCode = debug_info_data.getULEB128(&offset);
221
222 if (abbrCode) {
223 AbbrevDecl = cu->getAbbreviations()->getAbbreviationDeclaration(abbrCode);
224
225 if (AbbrevDecl) {
226 uint16_t tag = AbbrevDecl->getTag();
227
228 bool isCompileUnitTag = tag == DW_TAG_compile_unit;
229 if(cu && isCompileUnitTag)
230 const_cast<DWARFCompileUnit*>(cu)->setBaseAddress(0);
231
232 // Skip all data in the .debug_info for the attributes
233 const uint32_t numAttributes = AbbrevDecl->getNumAttributes();
234 for (uint32_t i = 0; i != numAttributes; ++i) {
235 uint16_t attr = AbbrevDecl->getAttrByIndex(i);
236 uint16_t form = AbbrevDecl->getFormByIndex(i);
237
238 if (isCompileUnitTag &&
239 ((attr == DW_AT_entry_pc) || (attr == DW_AT_low_pc))) {
240 DWARFFormValue form_value(form);
241 if (form_value.extractValue(debug_info_data, &offset, cu)) {
242 if (attr == DW_AT_low_pc || attr == DW_AT_entry_pc)
243 const_cast<DWARFCompileUnit*>(cu)
244 ->setBaseAddress(form_value.getUnsigned());
245 }
246 } else {
247 bool form_is_indirect = false;
248 do {
249 form_is_indirect = false;
250 register uint32_t form_size = 0;
251 switch (form) {
252 // Blocks if inlined data that have a length field and the data
253 // bytes // inlined in the .debug_info
254 case DW_FORM_block:
255 form_size = debug_info_data.getULEB128(&offset);
256 break;
257 case DW_FORM_block1:
258 form_size = debug_info_data.getU8(&offset);
259 break;
260 case DW_FORM_block2:
261 form_size = debug_info_data.getU16(&offset);
262 break;
263 case DW_FORM_block4:
264 form_size = debug_info_data.getU32(&offset);
265 break;
266
267 // Inlined NULL terminated C-strings
268 case DW_FORM_string:
269 debug_info_data.getCStr(&offset);
270 break;
271
272 // Compile unit address sized values
273 case DW_FORM_addr:
274 case DW_FORM_ref_addr:
275 form_size = cu_addr_size;
276 break;
277
278 // 1 byte values
279 case DW_FORM_data1:
280 case DW_FORM_flag:
281 case DW_FORM_ref1:
282 form_size = 1;
283 break;
284
285 // 2 byte values
286 case DW_FORM_data2:
287 case DW_FORM_ref2:
288 form_size = 2;
289 break;
290
291 // 4 byte values
292 case DW_FORM_strp:
293 form_size = 4;
294 break;
295
296 case DW_FORM_data4:
297 case DW_FORM_ref4:
298 form_size = 4;
299 break;
300
301 // 8 byte values
302 case DW_FORM_data8:
303 case DW_FORM_ref8:
304 form_size = 8;
305 break;
306
307 // signed or unsigned LEB 128 values
308 case DW_FORM_sdata:
309 case DW_FORM_udata:
310 case DW_FORM_ref_udata:
311 debug_info_data.getULEB128(&offset);
312 break;
313
314 case DW_FORM_indirect:
315 form = debug_info_data.getULEB128(&offset);
316 form_is_indirect = true;
317 break;
318
319 default:
320 *offset_ptr = offset;
321 return false;
322 }
323
324 offset += form_size;
325 } while (form_is_indirect);
326 }
327 }
328 *offset_ptr = offset;
329 return true;
330 }
331 } else {
332 AbbrevDecl = NULL;
333 *offset_ptr = offset;
334 return true; // NULL debug tag entry
335 }
336 }
337
338 return false;
339 }
340
341 uint32_t
getAttributeValue(const DWARFCompileUnit * cu,const uint16_t attr,DWARFFormValue & form_value,uint32_t * end_attr_offset_ptr) const342 DWARFDebugInfoEntryMinimal::getAttributeValue(const DWARFCompileUnit *cu,
343 const uint16_t attr,
344 DWARFFormValue &form_value,
345 uint32_t *end_attr_offset_ptr)
346 const {
347 if (AbbrevDecl) {
348 uint32_t attr_idx = AbbrevDecl->findAttributeIndex(attr);
349
350 if (attr_idx != -1U) {
351 uint32_t offset = getOffset();
352
353 DataExtractor debug_info_data = cu->getDebugInfoExtractor();
354
355 // Skip the abbreviation code so we are at the data for the attributes
356 debug_info_data.getULEB128(&offset);
357
358 uint32_t idx = 0;
359 while (idx < attr_idx)
360 DWARFFormValue::skipValue(AbbrevDecl->getFormByIndex(idx++),
361 debug_info_data, &offset, cu);
362
363 const uint32_t attr_offset = offset;
364 form_value = DWARFFormValue(AbbrevDecl->getFormByIndex(idx));
365 if (form_value.extractValue(debug_info_data, &offset, cu)) {
366 if (end_attr_offset_ptr)
367 *end_attr_offset_ptr = offset;
368 return attr_offset;
369 }
370 }
371 }
372
373 return 0;
374 }
375
376 const char*
getAttributeValueAsString(const DWARFCompileUnit * cu,const uint16_t attr,const char * fail_value) const377 DWARFDebugInfoEntryMinimal::getAttributeValueAsString(
378 const DWARFCompileUnit* cu,
379 const uint16_t attr,
380 const char* fail_value) const {
381 DWARFFormValue form_value;
382 if (getAttributeValue(cu, attr, form_value)) {
383 DataExtractor stringExtractor(cu->getContext().getStringSection(),
384 false, 0);
385 return form_value.getAsCString(&stringExtractor);
386 }
387 return fail_value;
388 }
389
390 uint64_t
getAttributeValueAsUnsigned(const DWARFCompileUnit * cu,const uint16_t attr,uint64_t fail_value) const391 DWARFDebugInfoEntryMinimal::getAttributeValueAsUnsigned(
392 const DWARFCompileUnit* cu,
393 const uint16_t attr,
394 uint64_t fail_value) const {
395 DWARFFormValue form_value;
396 if (getAttributeValue(cu, attr, form_value))
397 return form_value.getUnsigned();
398 return fail_value;
399 }
400
401 int64_t
getAttributeValueAsSigned(const DWARFCompileUnit * cu,const uint16_t attr,int64_t fail_value) const402 DWARFDebugInfoEntryMinimal::getAttributeValueAsSigned(
403 const DWARFCompileUnit* cu,
404 const uint16_t attr,
405 int64_t fail_value) const {
406 DWARFFormValue form_value;
407 if (getAttributeValue(cu, attr, form_value))
408 return form_value.getSigned();
409 return fail_value;
410 }
411
412 uint64_t
getAttributeValueAsReference(const DWARFCompileUnit * cu,const uint16_t attr,uint64_t fail_value) const413 DWARFDebugInfoEntryMinimal::getAttributeValueAsReference(
414 const DWARFCompileUnit* cu,
415 const uint16_t attr,
416 uint64_t fail_value) const {
417 DWARFFormValue form_value;
418 if (getAttributeValue(cu, attr, form_value))
419 return form_value.getReference(cu);
420 return fail_value;
421 }
422
423 void
buildAddressRangeTable(const DWARFCompileUnit * cu,DWARFDebugAranges * debug_aranges) const424 DWARFDebugInfoEntryMinimal::buildAddressRangeTable(const DWARFCompileUnit *cu,
425 DWARFDebugAranges *debug_aranges)
426 const {
427 if (AbbrevDecl) {
428 uint16_t tag = AbbrevDecl->getTag();
429 if (tag == DW_TAG_subprogram) {
430 uint64_t hi_pc = -1ULL;
431 uint64_t lo_pc = getAttributeValueAsUnsigned(cu, DW_AT_low_pc, -1ULL);
432 if (lo_pc != -1ULL)
433 hi_pc = getAttributeValueAsUnsigned(cu, DW_AT_high_pc, -1ULL);
434 if (hi_pc != -1ULL)
435 debug_aranges->appendRange(cu->getOffset(), lo_pc, hi_pc);
436 }
437
438 const DWARFDebugInfoEntryMinimal *child = getFirstChild();
439 while (child) {
440 child->buildAddressRangeTable(cu, debug_aranges);
441 child = child->getSibling();
442 }
443 }
444 }
445