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 uint32_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
208 bool
extract(const DWARFCompileUnit * cu,uint32_t * offset_ptr)209 DWARFDebugInfoEntryMinimal::extract(const DWARFCompileUnit *cu,
210 uint32_t *offset_ptr) {
211 DataExtractor debug_info_data = cu->getDebugInfoExtractor();
212 const uint32_t cu_end_offset = cu->getNextCompileUnitOffset();
213 const uint8_t cu_addr_size = cu->getAddressByteSize();
214 uint32_t offset = *offset_ptr;
215 if ((offset < cu_end_offset) && debug_info_data.isValidOffset(offset)) {
216 Offset = offset;
217
218 uint64_t abbrCode = debug_info_data.getULEB128(&offset);
219
220 if (abbrCode) {
221 AbbrevDecl = cu->getAbbreviations()->getAbbreviationDeclaration(abbrCode);
222
223 if (AbbrevDecl) {
224 uint16_t tag = AbbrevDecl->getTag();
225
226 bool isCompileUnitTag = tag == DW_TAG_compile_unit;
227 if(cu && isCompileUnitTag)
228 const_cast<DWARFCompileUnit*>(cu)->setBaseAddress(0);
229
230 // Skip all data in the .debug_info for the attributes
231 const uint32_t numAttributes = AbbrevDecl->getNumAttributes();
232 for (uint32_t i = 0; i != numAttributes; ++i) {
233 uint16_t attr = AbbrevDecl->getAttrByIndex(i);
234 uint16_t form = AbbrevDecl->getFormByIndex(i);
235
236 if (isCompileUnitTag &&
237 ((attr == DW_AT_entry_pc) || (attr == DW_AT_low_pc))) {
238 DWARFFormValue form_value(form);
239 if (form_value.extractValue(debug_info_data, &offset, cu)) {
240 if (attr == DW_AT_low_pc || attr == DW_AT_entry_pc)
241 const_cast<DWARFCompileUnit*>(cu)
242 ->setBaseAddress(form_value.getUnsigned());
243 }
244 } else {
245 bool form_is_indirect = false;
246 do {
247 form_is_indirect = false;
248 register uint32_t form_size = 0;
249 switch (form) {
250 // Blocks if inlined data that have a length field and the data
251 // bytes // inlined in the .debug_info
252 case DW_FORM_block:
253 form_size = debug_info_data.getULEB128(&offset);
254 break;
255 case DW_FORM_block1:
256 form_size = debug_info_data.getU8(&offset);
257 break;
258 case DW_FORM_block2:
259 form_size = debug_info_data.getU16(&offset);
260 break;
261 case DW_FORM_block4:
262 form_size = debug_info_data.getU32(&offset);
263 break;
264
265 // Inlined NULL terminated C-strings
266 case DW_FORM_string:
267 debug_info_data.getCStr(&offset);
268 break;
269
270 // Compile unit address sized values
271 case DW_FORM_addr:
272 case DW_FORM_ref_addr:
273 form_size = cu_addr_size;
274 break;
275
276 // 1 byte values
277 case DW_FORM_data1:
278 case DW_FORM_flag:
279 case DW_FORM_ref1:
280 form_size = 1;
281 break;
282
283 // 2 byte values
284 case DW_FORM_data2:
285 case DW_FORM_ref2:
286 form_size = 2;
287 break;
288
289 // 4 byte values
290 case DW_FORM_strp:
291 form_size = 4;
292 break;
293
294 case DW_FORM_data4:
295 case DW_FORM_ref4:
296 form_size = 4;
297 break;
298
299 // 8 byte values
300 case DW_FORM_data8:
301 case DW_FORM_ref8:
302 form_size = 8;
303 break;
304
305 // signed or unsigned LEB 128 values
306 case DW_FORM_sdata:
307 case DW_FORM_udata:
308 case DW_FORM_ref_udata:
309 debug_info_data.getULEB128(&offset);
310 break;
311
312 case DW_FORM_indirect:
313 form = debug_info_data.getULEB128(&offset);
314 form_is_indirect = true;
315 break;
316
317 default:
318 *offset_ptr = offset;
319 return false;
320 }
321
322 offset += form_size;
323 } while (form_is_indirect);
324 }
325 }
326 *offset_ptr = offset;
327 return true;
328 }
329 } else {
330 AbbrevDecl = NULL;
331 *offset_ptr = offset;
332 return true; // NULL debug tag entry
333 }
334 }
335
336 return false;
337 }
338
339 uint32_t
getAttributeValue(const DWARFCompileUnit * cu,const uint16_t attr,DWARFFormValue & form_value,uint32_t * end_attr_offset_ptr) const340 DWARFDebugInfoEntryMinimal::getAttributeValue(const DWARFCompileUnit *cu,
341 const uint16_t attr,
342 DWARFFormValue &form_value,
343 uint32_t *end_attr_offset_ptr)
344 const {
345 if (AbbrevDecl) {
346 uint32_t attr_idx = AbbrevDecl->findAttributeIndex(attr);
347
348 if (attr_idx != -1U) {
349 uint32_t offset = getOffset();
350
351 DataExtractor debug_info_data = cu->getDebugInfoExtractor();
352
353 // Skip the abbreviation code so we are at the data for the attributes
354 debug_info_data.getULEB128(&offset);
355
356 uint32_t idx = 0;
357 while (idx < attr_idx)
358 DWARFFormValue::skipValue(AbbrevDecl->getFormByIndex(idx++),
359 debug_info_data, &offset, cu);
360
361 const uint32_t attr_offset = offset;
362 form_value = DWARFFormValue(AbbrevDecl->getFormByIndex(idx));
363 if (form_value.extractValue(debug_info_data, &offset, cu)) {
364 if (end_attr_offset_ptr)
365 *end_attr_offset_ptr = offset;
366 return attr_offset;
367 }
368 }
369 }
370
371 return 0;
372 }
373
374 const char*
getAttributeValueAsString(const DWARFCompileUnit * cu,const uint16_t attr,const char * fail_value) const375 DWARFDebugInfoEntryMinimal::getAttributeValueAsString(
376 const DWARFCompileUnit* cu,
377 const uint16_t attr,
378 const char* fail_value) const {
379 DWARFFormValue form_value;
380 if (getAttributeValue(cu, attr, form_value)) {
381 DataExtractor stringExtractor(cu->getContext().getStringSection(),
382 false, 0);
383 return form_value.getAsCString(&stringExtractor);
384 }
385 return fail_value;
386 }
387
388 uint64_t
getAttributeValueAsUnsigned(const DWARFCompileUnit * cu,const uint16_t attr,uint64_t fail_value) const389 DWARFDebugInfoEntryMinimal::getAttributeValueAsUnsigned(
390 const DWARFCompileUnit* cu,
391 const uint16_t attr,
392 uint64_t fail_value) const {
393 DWARFFormValue form_value;
394 if (getAttributeValue(cu, attr, form_value))
395 return form_value.getUnsigned();
396 return fail_value;
397 }
398
399 int64_t
getAttributeValueAsSigned(const DWARFCompileUnit * cu,const uint16_t attr,int64_t fail_value) const400 DWARFDebugInfoEntryMinimal::getAttributeValueAsSigned(
401 const DWARFCompileUnit* cu,
402 const uint16_t attr,
403 int64_t fail_value) const {
404 DWARFFormValue form_value;
405 if (getAttributeValue(cu, attr, form_value))
406 return form_value.getSigned();
407 return fail_value;
408 }
409
410 uint64_t
getAttributeValueAsReference(const DWARFCompileUnit * cu,const uint16_t attr,uint64_t fail_value) const411 DWARFDebugInfoEntryMinimal::getAttributeValueAsReference(
412 const DWARFCompileUnit* cu,
413 const uint16_t attr,
414 uint64_t fail_value) const {
415 DWARFFormValue form_value;
416 if (getAttributeValue(cu, attr, form_value))
417 return form_value.getReference(cu);
418 return fail_value;
419 }
420
421 void
buildAddressRangeTable(const DWARFCompileUnit * cu,DWARFDebugAranges * debug_aranges) const422 DWARFDebugInfoEntryMinimal::buildAddressRangeTable(const DWARFCompileUnit *cu,
423 DWARFDebugAranges *debug_aranges)
424 const {
425 if (AbbrevDecl) {
426 uint16_t tag = AbbrevDecl->getTag();
427 if (tag == DW_TAG_subprogram) {
428 uint64_t hi_pc = -1ULL;
429 uint64_t lo_pc = getAttributeValueAsUnsigned(cu, DW_AT_low_pc, -1ULL);
430 if (lo_pc != -1ULL)
431 hi_pc = getAttributeValueAsUnsigned(cu, DW_AT_high_pc, -1ULL);
432 if (hi_pc != -1ULL)
433 debug_aranges->appendRange(cu->getOffset(), lo_pc, hi_pc);
434 }
435
436 const DWARFDebugInfoEntryMinimal *child = getFirstChild();
437 while (child) {
438 child->buildAddressRangeTable(cu, debug_aranges);
439 child = child->getSibling();
440 }
441 }
442 }
443