1 //===- DWARFFormValue.cpp -------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
10 #include "llvm/ADT/ArrayRef.h"
11 #include "llvm/ADT/None.h"
12 #include "llvm/ADT/Optional.h"
13 #include "llvm/ADT/StringRef.h"
14 #include "llvm/BinaryFormat/Dwarf.h"
15 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
16 #include "llvm/DebugInfo/DWARF/DWARFRelocMap.h"
17 #include "llvm/DebugInfo/DWARF/DWARFUnit.h"
18 #include "llvm/Support/ErrorHandling.h"
19 #include "llvm/Support/Format.h"
20 #include "llvm/Support/WithColor.h"
21 #include "llvm/Support/raw_ostream.h"
22 #include <cinttypes>
23 #include <cstdint>
24 #include <limits>
25
26 using namespace llvm;
27 using namespace dwarf;
28
29 static const DWARFFormValue::FormClass DWARF5FormClasses[] = {
30 DWARFFormValue::FC_Unknown, // 0x0
31 DWARFFormValue::FC_Address, // 0x01 DW_FORM_addr
32 DWARFFormValue::FC_Unknown, // 0x02 unused
33 DWARFFormValue::FC_Block, // 0x03 DW_FORM_block2
34 DWARFFormValue::FC_Block, // 0x04 DW_FORM_block4
35 DWARFFormValue::FC_Constant, // 0x05 DW_FORM_data2
36 // --- These can be FC_SectionOffset in DWARF3 and below:
37 DWARFFormValue::FC_Constant, // 0x06 DW_FORM_data4
38 DWARFFormValue::FC_Constant, // 0x07 DW_FORM_data8
39 // ---
40 DWARFFormValue::FC_String, // 0x08 DW_FORM_string
41 DWARFFormValue::FC_Block, // 0x09 DW_FORM_block
42 DWARFFormValue::FC_Block, // 0x0a DW_FORM_block1
43 DWARFFormValue::FC_Constant, // 0x0b DW_FORM_data1
44 DWARFFormValue::FC_Flag, // 0x0c DW_FORM_flag
45 DWARFFormValue::FC_Constant, // 0x0d DW_FORM_sdata
46 DWARFFormValue::FC_String, // 0x0e DW_FORM_strp
47 DWARFFormValue::FC_Constant, // 0x0f DW_FORM_udata
48 DWARFFormValue::FC_Reference, // 0x10 DW_FORM_ref_addr
49 DWARFFormValue::FC_Reference, // 0x11 DW_FORM_ref1
50 DWARFFormValue::FC_Reference, // 0x12 DW_FORM_ref2
51 DWARFFormValue::FC_Reference, // 0x13 DW_FORM_ref4
52 DWARFFormValue::FC_Reference, // 0x14 DW_FORM_ref8
53 DWARFFormValue::FC_Reference, // 0x15 DW_FORM_ref_udata
54 DWARFFormValue::FC_Indirect, // 0x16 DW_FORM_indirect
55 DWARFFormValue::FC_SectionOffset, // 0x17 DW_FORM_sec_offset
56 DWARFFormValue::FC_Exprloc, // 0x18 DW_FORM_exprloc
57 DWARFFormValue::FC_Flag, // 0x19 DW_FORM_flag_present
58 DWARFFormValue::FC_String, // 0x1a DW_FORM_strx
59 DWARFFormValue::FC_Address, // 0x1b DW_FORM_addrx
60 DWARFFormValue::FC_Reference, // 0x1c DW_FORM_ref_sup4
61 DWARFFormValue::FC_String, // 0x1d DW_FORM_strp_sup
62 DWARFFormValue::FC_Constant, // 0x1e DW_FORM_data16
63 DWARFFormValue::FC_String, // 0x1f DW_FORM_line_strp
64 DWARFFormValue::FC_Reference, // 0x20 DW_FORM_ref_sig8
65 DWARFFormValue::FC_Constant, // 0x21 DW_FORM_implicit_const
66 DWARFFormValue::FC_SectionOffset, // 0x22 DW_FORM_loclistx
67 DWARFFormValue::FC_SectionOffset, // 0x23 DW_FORM_rnglistx
68 DWARFFormValue::FC_Reference, // 0x24 DW_FORM_ref_sup8
69 DWARFFormValue::FC_String, // 0x25 DW_FORM_strx1
70 DWARFFormValue::FC_String, // 0x26 DW_FORM_strx2
71 DWARFFormValue::FC_String, // 0x27 DW_FORM_strx3
72 DWARFFormValue::FC_String, // 0x28 DW_FORM_strx4
73 DWARFFormValue::FC_Address, // 0x29 DW_FORM_addrx1
74 DWARFFormValue::FC_Address, // 0x2a DW_FORM_addrx2
75 DWARFFormValue::FC_Address, // 0x2b DW_FORM_addrx3
76 DWARFFormValue::FC_Address, // 0x2c DW_FORM_addrx4
77
78 };
79
createFromSValue(dwarf::Form F,int64_t V)80 DWARFFormValue DWARFFormValue::createFromSValue(dwarf::Form F, int64_t V) {
81 return DWARFFormValue(F, ValueType(V));
82 }
83
createFromUValue(dwarf::Form F,uint64_t V)84 DWARFFormValue DWARFFormValue::createFromUValue(dwarf::Form F, uint64_t V) {
85 return DWARFFormValue(F, ValueType(V));
86 }
87
createFromPValue(dwarf::Form F,const char * V)88 DWARFFormValue DWARFFormValue::createFromPValue(dwarf::Form F, const char *V) {
89 return DWARFFormValue(F, ValueType(V));
90 }
91
createFromBlockValue(dwarf::Form F,ArrayRef<uint8_t> D)92 DWARFFormValue DWARFFormValue::createFromBlockValue(dwarf::Form F,
93 ArrayRef<uint8_t> D) {
94 ValueType V;
95 V.uval = D.size();
96 V.data = D.data();
97 return DWARFFormValue(F, V);
98 }
99
createFromUnit(dwarf::Form F,const DWARFUnit * U,uint64_t * OffsetPtr)100 DWARFFormValue DWARFFormValue::createFromUnit(dwarf::Form F, const DWARFUnit *U,
101 uint64_t *OffsetPtr) {
102 DWARFFormValue FormValue(F);
103 FormValue.extractValue(U->getDebugInfoExtractor(), OffsetPtr,
104 U->getFormParams(), U);
105 return FormValue;
106 }
107
skipValue(dwarf::Form Form,DataExtractor DebugInfoData,uint64_t * OffsetPtr,const dwarf::FormParams Params)108 bool DWARFFormValue::skipValue(dwarf::Form Form, DataExtractor DebugInfoData,
109 uint64_t *OffsetPtr,
110 const dwarf::FormParams Params) {
111 bool Indirect = false;
112 do {
113 switch (Form) {
114 // Blocks of inlined data that have a length field and the data bytes
115 // inlined in the .debug_info.
116 case DW_FORM_exprloc:
117 case DW_FORM_block: {
118 uint64_t size = DebugInfoData.getULEB128(OffsetPtr);
119 *OffsetPtr += size;
120 return true;
121 }
122 case DW_FORM_block1: {
123 uint8_t size = DebugInfoData.getU8(OffsetPtr);
124 *OffsetPtr += size;
125 return true;
126 }
127 case DW_FORM_block2: {
128 uint16_t size = DebugInfoData.getU16(OffsetPtr);
129 *OffsetPtr += size;
130 return true;
131 }
132 case DW_FORM_block4: {
133 uint32_t size = DebugInfoData.getU32(OffsetPtr);
134 *OffsetPtr += size;
135 return true;
136 }
137
138 // Inlined NULL terminated C-strings.
139 case DW_FORM_string:
140 DebugInfoData.getCStr(OffsetPtr);
141 return true;
142
143 case DW_FORM_addr:
144 case DW_FORM_ref_addr:
145 case DW_FORM_flag_present:
146 case DW_FORM_data1:
147 case DW_FORM_data2:
148 case DW_FORM_data4:
149 case DW_FORM_data8:
150 case DW_FORM_data16:
151 case DW_FORM_flag:
152 case DW_FORM_ref1:
153 case DW_FORM_ref2:
154 case DW_FORM_ref4:
155 case DW_FORM_ref8:
156 case DW_FORM_ref_sig8:
157 case DW_FORM_ref_sup4:
158 case DW_FORM_ref_sup8:
159 case DW_FORM_strx1:
160 case DW_FORM_strx2:
161 case DW_FORM_strx4:
162 case DW_FORM_addrx1:
163 case DW_FORM_addrx2:
164 case DW_FORM_addrx4:
165 case DW_FORM_sec_offset:
166 case DW_FORM_strp:
167 case DW_FORM_strp_sup:
168 case DW_FORM_line_strp:
169 case DW_FORM_GNU_ref_alt:
170 case DW_FORM_GNU_strp_alt:
171 if (Optional<uint8_t> FixedSize =
172 dwarf::getFixedFormByteSize(Form, Params)) {
173 *OffsetPtr += *FixedSize;
174 return true;
175 }
176 return false;
177
178 // signed or unsigned LEB 128 values.
179 case DW_FORM_sdata:
180 DebugInfoData.getSLEB128(OffsetPtr);
181 return true;
182
183 case DW_FORM_udata:
184 case DW_FORM_ref_udata:
185 case DW_FORM_strx:
186 case DW_FORM_addrx:
187 case DW_FORM_loclistx:
188 case DW_FORM_rnglistx:
189 case DW_FORM_GNU_addr_index:
190 case DW_FORM_GNU_str_index:
191 DebugInfoData.getULEB128(OffsetPtr);
192 return true;
193
194 case DW_FORM_indirect:
195 Indirect = true;
196 Form = static_cast<dwarf::Form>(DebugInfoData.getULEB128(OffsetPtr));
197 break;
198
199 default:
200 return false;
201 }
202 } while (Indirect);
203 return true;
204 }
205
isFormClass(DWARFFormValue::FormClass FC) const206 bool DWARFFormValue::isFormClass(DWARFFormValue::FormClass FC) const {
207 // First, check DWARF5 form classes.
208 if (Form < makeArrayRef(DWARF5FormClasses).size() &&
209 DWARF5FormClasses[Form] == FC)
210 return true;
211 // Check more forms from extensions and proposals.
212 switch (Form) {
213 case DW_FORM_GNU_ref_alt:
214 return (FC == FC_Reference);
215 case DW_FORM_GNU_addr_index:
216 return (FC == FC_Address);
217 case DW_FORM_GNU_str_index:
218 case DW_FORM_GNU_strp_alt:
219 return (FC == FC_String);
220 default:
221 break;
222 }
223
224 if (FC == FC_SectionOffset) {
225 if (Form == DW_FORM_strp || Form == DW_FORM_line_strp)
226 return true;
227 // In DWARF3 DW_FORM_data4 and DW_FORM_data8 served also as a section
228 // offset. If we don't have a DWARFUnit, default to the old behavior.
229 if (Form == DW_FORM_data4 || Form == DW_FORM_data8)
230 return !U || U->getVersion() <= 3;
231 }
232
233 return false;
234 }
235
extractValue(const DWARFDataExtractor & Data,uint64_t * OffsetPtr,dwarf::FormParams FP,const DWARFContext * Ctx,const DWARFUnit * CU)236 bool DWARFFormValue::extractValue(const DWARFDataExtractor &Data,
237 uint64_t *OffsetPtr, dwarf::FormParams FP,
238 const DWARFContext *Ctx,
239 const DWARFUnit *CU) {
240 if (!Ctx && CU)
241 Ctx = &CU->getContext();
242 C = Ctx;
243 U = CU;
244 bool Indirect = false;
245 bool IsBlock = false;
246 Value.data = nullptr;
247 // Read the value for the form into value and follow and DW_FORM_indirect
248 // instances we run into
249 do {
250 Indirect = false;
251 switch (Form) {
252 case DW_FORM_addr:
253 case DW_FORM_ref_addr: {
254 uint16_t Size =
255 (Form == DW_FORM_addr) ? FP.AddrSize : FP.getRefAddrByteSize();
256 Value.uval = Data.getRelocatedValue(Size, OffsetPtr, &Value.SectionIndex);
257 break;
258 }
259 case DW_FORM_exprloc:
260 case DW_FORM_block:
261 Value.uval = Data.getULEB128(OffsetPtr);
262 IsBlock = true;
263 break;
264 case DW_FORM_block1:
265 Value.uval = Data.getU8(OffsetPtr);
266 IsBlock = true;
267 break;
268 case DW_FORM_block2:
269 Value.uval = Data.getU16(OffsetPtr);
270 IsBlock = true;
271 break;
272 case DW_FORM_block4:
273 Value.uval = Data.getU32(OffsetPtr);
274 IsBlock = true;
275 break;
276 case DW_FORM_data1:
277 case DW_FORM_ref1:
278 case DW_FORM_flag:
279 case DW_FORM_strx1:
280 case DW_FORM_addrx1:
281 Value.uval = Data.getU8(OffsetPtr);
282 break;
283 case DW_FORM_data2:
284 case DW_FORM_ref2:
285 case DW_FORM_strx2:
286 case DW_FORM_addrx2:
287 Value.uval = Data.getU16(OffsetPtr);
288 break;
289 case DW_FORM_strx3:
290 Value.uval = Data.getU24(OffsetPtr);
291 break;
292 case DW_FORM_data4:
293 case DW_FORM_ref4:
294 case DW_FORM_ref_sup4:
295 case DW_FORM_strx4:
296 case DW_FORM_addrx4:
297 Value.uval = Data.getRelocatedValue(4, OffsetPtr);
298 break;
299 case DW_FORM_data8:
300 case DW_FORM_ref8:
301 case DW_FORM_ref_sup8:
302 Value.uval = Data.getRelocatedValue(8, OffsetPtr);
303 break;
304 case DW_FORM_data16:
305 // Treat this like a 16-byte block.
306 Value.uval = 16;
307 IsBlock = true;
308 break;
309 case DW_FORM_sdata:
310 Value.sval = Data.getSLEB128(OffsetPtr);
311 break;
312 case DW_FORM_udata:
313 case DW_FORM_ref_udata:
314 case DW_FORM_rnglistx:
315 case DW_FORM_loclistx:
316 Value.uval = Data.getULEB128(OffsetPtr);
317 break;
318 case DW_FORM_string:
319 Value.cstr = Data.getCStr(OffsetPtr);
320 break;
321 case DW_FORM_indirect:
322 Form = static_cast<dwarf::Form>(Data.getULEB128(OffsetPtr));
323 Indirect = true;
324 break;
325 case DW_FORM_strp:
326 case DW_FORM_sec_offset:
327 case DW_FORM_GNU_ref_alt:
328 case DW_FORM_GNU_strp_alt:
329 case DW_FORM_line_strp:
330 case DW_FORM_strp_sup: {
331 Value.uval =
332 Data.getRelocatedValue(FP.getDwarfOffsetByteSize(), OffsetPtr);
333 break;
334 }
335 case DW_FORM_flag_present:
336 Value.uval = 1;
337 break;
338 case DW_FORM_ref_sig8:
339 Value.uval = Data.getU64(OffsetPtr);
340 break;
341 case DW_FORM_GNU_addr_index:
342 case DW_FORM_GNU_str_index:
343 case DW_FORM_addrx:
344 case DW_FORM_strx:
345 Value.uval = Data.getULEB128(OffsetPtr);
346 break;
347 default:
348 // DWARFFormValue::skipValue() will have caught this and caused all
349 // DWARF DIEs to fail to be parsed, so this code is not be reachable.
350 llvm_unreachable("unsupported form");
351 }
352 } while (Indirect);
353
354 if (IsBlock) {
355 StringRef Str = Data.getData().substr(*OffsetPtr, Value.uval);
356 Value.data = nullptr;
357 if (!Str.empty()) {
358 Value.data = Str.bytes_begin();
359 *OffsetPtr += Value.uval;
360 }
361 }
362
363 return true;
364 }
365
dumpSectionedAddress(raw_ostream & OS,DIDumpOptions DumpOpts,object::SectionedAddress SA) const366 void DWARFFormValue::dumpSectionedAddress(raw_ostream &OS,
367 DIDumpOptions DumpOpts,
368 object::SectionedAddress SA) const {
369 OS << format("0x%016" PRIx64, SA.Address);
370 dumpAddressSection(U->getContext().getDWARFObj(), OS, DumpOpts,
371 SA.SectionIndex);
372 }
373
dumpAddressSection(const DWARFObject & Obj,raw_ostream & OS,DIDumpOptions DumpOpts,uint64_t SectionIndex)374 void DWARFFormValue::dumpAddressSection(const DWARFObject &Obj, raw_ostream &OS,
375 DIDumpOptions DumpOpts,
376 uint64_t SectionIndex) {
377 if (!DumpOpts.Verbose || SectionIndex == -1ULL)
378 return;
379 ArrayRef<SectionName> SectionNames = Obj.getSectionNames();
380 const auto &SecRef = SectionNames[SectionIndex];
381
382 OS << " \"" << SecRef.Name << '\"';
383
384 // Print section index if name is not unique.
385 if (!SecRef.IsNameUnique)
386 OS << format(" [%" PRIu64 "]", SectionIndex);
387 }
388
dump(raw_ostream & OS,DIDumpOptions DumpOpts) const389 void DWARFFormValue::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const {
390 uint64_t UValue = Value.uval;
391 bool CURelativeOffset = false;
392 raw_ostream &AddrOS = DumpOpts.ShowAddresses
393 ? WithColor(OS, HighlightColor::Address).get()
394 : nulls();
395 switch (Form) {
396 case DW_FORM_addr:
397 dumpSectionedAddress(AddrOS, DumpOpts, {Value.uval, Value.SectionIndex});
398 break;
399 case DW_FORM_addrx:
400 case DW_FORM_addrx1:
401 case DW_FORM_addrx2:
402 case DW_FORM_addrx3:
403 case DW_FORM_addrx4:
404 case DW_FORM_GNU_addr_index: {
405 if (U == nullptr) {
406 OS << "<invalid dwarf unit>";
407 break;
408 }
409 Optional<object::SectionedAddress> A = U->getAddrOffsetSectionItem(UValue);
410 if (!A || DumpOpts.Verbose)
411 AddrOS << format("indexed (%8.8x) address = ", (uint32_t)UValue);
412 if (A)
413 dumpSectionedAddress(AddrOS, DumpOpts, *A);
414 else
415 OS << "<unresolved>";
416 break;
417 }
418 case DW_FORM_flag_present:
419 OS << "true";
420 break;
421 case DW_FORM_flag:
422 case DW_FORM_data1:
423 OS << format("0x%02x", (uint8_t)UValue);
424 break;
425 case DW_FORM_data2:
426 OS << format("0x%04x", (uint16_t)UValue);
427 break;
428 case DW_FORM_data4:
429 OS << format("0x%08x", (uint32_t)UValue);
430 break;
431 case DW_FORM_ref_sig8:
432 AddrOS << format("0x%016" PRIx64, UValue);
433 break;
434 case DW_FORM_data8:
435 OS << format("0x%016" PRIx64, UValue);
436 break;
437 case DW_FORM_data16:
438 OS << format_bytes(ArrayRef<uint8_t>(Value.data, 16), None, 16, 16);
439 break;
440 case DW_FORM_string:
441 OS << '"';
442 OS.write_escaped(Value.cstr);
443 OS << '"';
444 break;
445 case DW_FORM_exprloc:
446 case DW_FORM_block:
447 case DW_FORM_block1:
448 case DW_FORM_block2:
449 case DW_FORM_block4:
450 if (UValue > 0) {
451 switch (Form) {
452 case DW_FORM_exprloc:
453 case DW_FORM_block:
454 AddrOS << format("<0x%" PRIx64 "> ", UValue);
455 break;
456 case DW_FORM_block1:
457 AddrOS << format("<0x%2.2x> ", (uint8_t)UValue);
458 break;
459 case DW_FORM_block2:
460 AddrOS << format("<0x%4.4x> ", (uint16_t)UValue);
461 break;
462 case DW_FORM_block4:
463 AddrOS << format("<0x%8.8x> ", (uint32_t)UValue);
464 break;
465 default:
466 break;
467 }
468
469 const uint8_t *DataPtr = Value.data;
470 if (DataPtr) {
471 // UValue contains size of block
472 const uint8_t *EndDataPtr = DataPtr + UValue;
473 while (DataPtr < EndDataPtr) {
474 AddrOS << format("%2.2x ", *DataPtr);
475 ++DataPtr;
476 }
477 } else
478 OS << "NULL";
479 }
480 break;
481
482 case DW_FORM_sdata:
483 OS << Value.sval;
484 break;
485 case DW_FORM_udata:
486 OS << Value.uval;
487 break;
488 case DW_FORM_strp:
489 if (DumpOpts.Verbose)
490 OS << format(" .debug_str[0x%8.8x] = ", (uint32_t)UValue);
491 dumpString(OS);
492 break;
493 case DW_FORM_line_strp:
494 if (DumpOpts.Verbose)
495 OS << format(" .debug_line_str[0x%8.8x] = ", (uint32_t)UValue);
496 dumpString(OS);
497 break;
498 case DW_FORM_strx:
499 case DW_FORM_strx1:
500 case DW_FORM_strx2:
501 case DW_FORM_strx3:
502 case DW_FORM_strx4:
503 case DW_FORM_GNU_str_index:
504 if (DumpOpts.Verbose)
505 OS << format("indexed (%8.8x) string = ", (uint32_t)UValue);
506 dumpString(OS);
507 break;
508 case DW_FORM_GNU_strp_alt:
509 if (DumpOpts.Verbose)
510 OS << format("alt indirect string, offset: 0x%" PRIx64 "", UValue);
511 dumpString(OS);
512 break;
513 case DW_FORM_ref_addr:
514 AddrOS << format("0x%016" PRIx64, UValue);
515 break;
516 case DW_FORM_ref1:
517 CURelativeOffset = true;
518 if (DumpOpts.Verbose)
519 AddrOS << format("cu + 0x%2.2x", (uint8_t)UValue);
520 break;
521 case DW_FORM_ref2:
522 CURelativeOffset = true;
523 if (DumpOpts.Verbose)
524 AddrOS << format("cu + 0x%4.4x", (uint16_t)UValue);
525 break;
526 case DW_FORM_ref4:
527 CURelativeOffset = true;
528 if (DumpOpts.Verbose)
529 AddrOS << format("cu + 0x%4.4x", (uint32_t)UValue);
530 break;
531 case DW_FORM_ref8:
532 CURelativeOffset = true;
533 if (DumpOpts.Verbose)
534 AddrOS << format("cu + 0x%8.8" PRIx64, UValue);
535 break;
536 case DW_FORM_ref_udata:
537 CURelativeOffset = true;
538 if (DumpOpts.Verbose)
539 AddrOS << format("cu + 0x%" PRIx64, UValue);
540 break;
541 case DW_FORM_GNU_ref_alt:
542 AddrOS << format("<alt 0x%" PRIx64 ">", UValue);
543 break;
544
545 // All DW_FORM_indirect attributes should be resolved prior to calling
546 // this function
547 case DW_FORM_indirect:
548 OS << "DW_FORM_indirect";
549 break;
550
551 case DW_FORM_rnglistx:
552 OS << format("indexed (0x%x) rangelist = ", (uint32_t)UValue);
553 break;
554
555 case DW_FORM_loclistx:
556 OS << format("indexed (0x%x) loclist = ", (uint32_t)UValue);
557 break;
558
559 // Should be formatted to 64-bit for DWARF64.
560 case DW_FORM_sec_offset:
561 AddrOS << format("0x%08x", (uint32_t)UValue);
562 break;
563
564 default:
565 OS << format("DW_FORM(0x%4.4x)", Form);
566 break;
567 }
568
569 if (CURelativeOffset) {
570 if (DumpOpts.Verbose)
571 OS << " => {";
572 if (DumpOpts.ShowAddresses)
573 WithColor(OS, HighlightColor::Address).get()
574 << format("0x%8.8" PRIx64, UValue + (U ? U->getOffset() : 0));
575 if (DumpOpts.Verbose)
576 OS << "}";
577 }
578 }
579
dumpString(raw_ostream & OS) const580 void DWARFFormValue::dumpString(raw_ostream &OS) const {
581 Optional<const char *> DbgStr = getAsCString();
582 if (DbgStr.hasValue()) {
583 auto COS = WithColor(OS, HighlightColor::String);
584 COS.get() << '"';
585 COS.get().write_escaped(DbgStr.getValue());
586 COS.get() << '"';
587 }
588 }
589
getAsCString() const590 Optional<const char *> DWARFFormValue::getAsCString() const {
591 if (!isFormClass(FC_String))
592 return None;
593 if (Form == DW_FORM_string)
594 return Value.cstr;
595 // FIXME: Add support for DW_FORM_GNU_strp_alt
596 if (Form == DW_FORM_GNU_strp_alt || C == nullptr)
597 return None;
598 uint64_t Offset = Value.uval;
599 if (Form == DW_FORM_line_strp) {
600 // .debug_line_str is tracked in the Context.
601 if (const char *Str = C->getLineStringExtractor().getCStr(&Offset))
602 return Str;
603 return None;
604 }
605 if (Form == DW_FORM_GNU_str_index || Form == DW_FORM_strx ||
606 Form == DW_FORM_strx1 || Form == DW_FORM_strx2 || Form == DW_FORM_strx3 ||
607 Form == DW_FORM_strx4) {
608 if (!U)
609 return None;
610 Optional<uint64_t> StrOffset = U->getStringOffsetSectionItem(Offset);
611 if (!StrOffset)
612 return None;
613 Offset = *StrOffset;
614 }
615 // Prefer the Unit's string extractor, because for .dwo it will point to
616 // .debug_str.dwo, while the Context's extractor always uses .debug_str.
617 if (U) {
618 if (const char *Str = U->getStringExtractor().getCStr(&Offset))
619 return Str;
620 return None;
621 }
622 if (const char *Str = C->getStringExtractor().getCStr(&Offset))
623 return Str;
624 return None;
625 }
626
getAsAddress() const627 Optional<uint64_t> DWARFFormValue::getAsAddress() const {
628 if (auto SA = getAsSectionedAddress())
629 return SA->Address;
630 return None;
631 }
632
633 Optional<object::SectionedAddress>
getAsSectionedAddress() const634 DWARFFormValue::getAsSectionedAddress() const {
635 if (!isFormClass(FC_Address))
636 return None;
637 if (Form == DW_FORM_GNU_addr_index || Form == DW_FORM_addrx) {
638 uint32_t Index = Value.uval;
639 if (!U)
640 return None;
641 Optional<object::SectionedAddress> SA = U->getAddrOffsetSectionItem(Index);
642 if (!SA)
643 return None;
644 return SA;
645 }
646 return {{Value.uval, Value.SectionIndex}};
647 }
648
getAsReference() const649 Optional<uint64_t> DWARFFormValue::getAsReference() const {
650 if (auto R = getAsRelativeReference())
651 return R->Unit ? R->Unit->getOffset() + R->Offset : R->Offset;
652 return None;
653 }
654
getAsRelativeReference() const655 Optional<DWARFFormValue::UnitOffset> DWARFFormValue::getAsRelativeReference() const {
656 if (!isFormClass(FC_Reference))
657 return None;
658 switch (Form) {
659 case DW_FORM_ref1:
660 case DW_FORM_ref2:
661 case DW_FORM_ref4:
662 case DW_FORM_ref8:
663 case DW_FORM_ref_udata:
664 if (!U)
665 return None;
666 return UnitOffset{const_cast<DWARFUnit*>(U), Value.uval};
667 case DW_FORM_ref_addr:
668 case DW_FORM_ref_sig8:
669 case DW_FORM_GNU_ref_alt:
670 return UnitOffset{nullptr, Value.uval};
671 default:
672 return None;
673 }
674 }
675
getAsSectionOffset() const676 Optional<uint64_t> DWARFFormValue::getAsSectionOffset() const {
677 if (!isFormClass(FC_SectionOffset))
678 return None;
679 return Value.uval;
680 }
681
getAsUnsignedConstant() const682 Optional<uint64_t> DWARFFormValue::getAsUnsignedConstant() const {
683 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) ||
684 Form == DW_FORM_sdata)
685 return None;
686 return Value.uval;
687 }
688
getAsSignedConstant() const689 Optional<int64_t> DWARFFormValue::getAsSignedConstant() const {
690 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) ||
691 (Form == DW_FORM_udata &&
692 uint64_t(std::numeric_limits<int64_t>::max()) < Value.uval))
693 return None;
694 switch (Form) {
695 case DW_FORM_data4:
696 return int32_t(Value.uval);
697 case DW_FORM_data2:
698 return int16_t(Value.uval);
699 case DW_FORM_data1:
700 return int8_t(Value.uval);
701 case DW_FORM_sdata:
702 case DW_FORM_data8:
703 default:
704 return Value.sval;
705 }
706 }
707
getAsBlock() const708 Optional<ArrayRef<uint8_t>> DWARFFormValue::getAsBlock() const {
709 if (!isFormClass(FC_Block) && !isFormClass(FC_Exprloc) &&
710 Form != DW_FORM_data16)
711 return None;
712 return makeArrayRef(Value.data, Value.uval);
713 }
714
getAsCStringOffset() const715 Optional<uint64_t> DWARFFormValue::getAsCStringOffset() const {
716 if (!isFormClass(FC_String) && Form == DW_FORM_string)
717 return None;
718 return Value.uval;
719 }
720
getAsReferenceUVal() const721 Optional<uint64_t> DWARFFormValue::getAsReferenceUVal() const {
722 if (!isFormClass(FC_Reference))
723 return None;
724 return Value.uval;
725 }
726