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/StringRef.h"
12 #include "llvm/BinaryFormat/Dwarf.h"
13 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
14 #include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h"
15 #include "llvm/DebugInfo/DWARF/DWARFDebugLine.h"
16 #include "llvm/DebugInfo/DWARF/DWARFObject.h"
17 #include "llvm/DebugInfo/DWARF/DWARFSection.h"
18 #include "llvm/DebugInfo/DWARF/DWARFUnit.h"
19 #include "llvm/Support/ErrorHandling.h"
20 #include "llvm/Support/Format.h"
21 #include "llvm/Support/WithColor.h"
22 #include "llvm/Support/raw_ostream.h"
23 #include <cinttypes>
24 #include <cstdint>
25 #include <limits>
26 #include <optional>
27
28 using namespace llvm;
29 using namespace dwarf;
30
31 static const DWARFFormValue::FormClass DWARF5FormClasses[] = {
32 DWARFFormValue::FC_Unknown, // 0x0
33 DWARFFormValue::FC_Address, // 0x01 DW_FORM_addr
34 DWARFFormValue::FC_Unknown, // 0x02 unused
35 DWARFFormValue::FC_Block, // 0x03 DW_FORM_block2
36 DWARFFormValue::FC_Block, // 0x04 DW_FORM_block4
37 DWARFFormValue::FC_Constant, // 0x05 DW_FORM_data2
38 // --- These can be FC_SectionOffset in DWARF3 and below:
39 DWARFFormValue::FC_Constant, // 0x06 DW_FORM_data4
40 DWARFFormValue::FC_Constant, // 0x07 DW_FORM_data8
41 // ---
42 DWARFFormValue::FC_String, // 0x08 DW_FORM_string
43 DWARFFormValue::FC_Block, // 0x09 DW_FORM_block
44 DWARFFormValue::FC_Block, // 0x0a DW_FORM_block1
45 DWARFFormValue::FC_Constant, // 0x0b DW_FORM_data1
46 DWARFFormValue::FC_Flag, // 0x0c DW_FORM_flag
47 DWARFFormValue::FC_Constant, // 0x0d DW_FORM_sdata
48 DWARFFormValue::FC_String, // 0x0e DW_FORM_strp
49 DWARFFormValue::FC_Constant, // 0x0f DW_FORM_udata
50 DWARFFormValue::FC_Reference, // 0x10 DW_FORM_ref_addr
51 DWARFFormValue::FC_Reference, // 0x11 DW_FORM_ref1
52 DWARFFormValue::FC_Reference, // 0x12 DW_FORM_ref2
53 DWARFFormValue::FC_Reference, // 0x13 DW_FORM_ref4
54 DWARFFormValue::FC_Reference, // 0x14 DW_FORM_ref8
55 DWARFFormValue::FC_Reference, // 0x15 DW_FORM_ref_udata
56 DWARFFormValue::FC_Indirect, // 0x16 DW_FORM_indirect
57 DWARFFormValue::FC_SectionOffset, // 0x17 DW_FORM_sec_offset
58 DWARFFormValue::FC_Exprloc, // 0x18 DW_FORM_exprloc
59 DWARFFormValue::FC_Flag, // 0x19 DW_FORM_flag_present
60 DWARFFormValue::FC_String, // 0x1a DW_FORM_strx
61 DWARFFormValue::FC_Address, // 0x1b DW_FORM_addrx
62 DWARFFormValue::FC_Reference, // 0x1c DW_FORM_ref_sup4
63 DWARFFormValue::FC_String, // 0x1d DW_FORM_strp_sup
64 DWARFFormValue::FC_Constant, // 0x1e DW_FORM_data16
65 DWARFFormValue::FC_String, // 0x1f DW_FORM_line_strp
66 DWARFFormValue::FC_Reference, // 0x20 DW_FORM_ref_sig8
67 DWARFFormValue::FC_Constant, // 0x21 DW_FORM_implicit_const
68 DWARFFormValue::FC_SectionOffset, // 0x22 DW_FORM_loclistx
69 DWARFFormValue::FC_SectionOffset, // 0x23 DW_FORM_rnglistx
70 DWARFFormValue::FC_Reference, // 0x24 DW_FORM_ref_sup8
71 DWARFFormValue::FC_String, // 0x25 DW_FORM_strx1
72 DWARFFormValue::FC_String, // 0x26 DW_FORM_strx2
73 DWARFFormValue::FC_String, // 0x27 DW_FORM_strx3
74 DWARFFormValue::FC_String, // 0x28 DW_FORM_strx4
75 DWARFFormValue::FC_Address, // 0x29 DW_FORM_addrx1
76 DWARFFormValue::FC_Address, // 0x2a DW_FORM_addrx2
77 DWARFFormValue::FC_Address, // 0x2b DW_FORM_addrx3
78 DWARFFormValue::FC_Address, // 0x2c DW_FORM_addrx4
79 DWARFFormValue::FC_Address, // 0x2001 DW_FORM_addrx_offset
80 };
81
createFromSValue(dwarf::Form F,int64_t V)82 DWARFFormValue DWARFFormValue::createFromSValue(dwarf::Form F, int64_t V) {
83 return DWARFFormValue(F, ValueType(V));
84 }
85
createFromUValue(dwarf::Form F,uint64_t V)86 DWARFFormValue DWARFFormValue::createFromUValue(dwarf::Form F, uint64_t V) {
87 return DWARFFormValue(F, ValueType(V));
88 }
89
createFromPValue(dwarf::Form F,const char * V)90 DWARFFormValue DWARFFormValue::createFromPValue(dwarf::Form F, const char *V) {
91 return DWARFFormValue(F, ValueType(V));
92 }
93
createFromBlockValue(dwarf::Form F,ArrayRef<uint8_t> D)94 DWARFFormValue DWARFFormValue::createFromBlockValue(dwarf::Form F,
95 ArrayRef<uint8_t> D) {
96 ValueType V;
97 V.uval = D.size();
98 V.data = D.data();
99 return DWARFFormValue(F, V);
100 }
101
createFromUnit(dwarf::Form F,const DWARFUnit * U,uint64_t * OffsetPtr)102 DWARFFormValue DWARFFormValue::createFromUnit(dwarf::Form F, const DWARFUnit *U,
103 uint64_t *OffsetPtr) {
104 DWARFFormValue FormValue(F);
105 FormValue.extractValue(U->getDebugInfoExtractor(), OffsetPtr,
106 U->getFormParams(), U);
107 return FormValue;
108 }
109
skipValue(dwarf::Form Form,DataExtractor DebugInfoData,uint64_t * OffsetPtr,const dwarf::FormParams Params)110 bool DWARFFormValue::skipValue(dwarf::Form Form, DataExtractor DebugInfoData,
111 uint64_t *OffsetPtr,
112 const dwarf::FormParams Params) {
113 bool Indirect = false;
114 do {
115 switch (Form) {
116 // Blocks of inlined data that have a length field and the data bytes
117 // inlined in the .debug_info.
118 case DW_FORM_exprloc:
119 case DW_FORM_block: {
120 uint64_t size = DebugInfoData.getULEB128(OffsetPtr);
121 *OffsetPtr += size;
122 return true;
123 }
124 case DW_FORM_block1: {
125 uint8_t size = DebugInfoData.getU8(OffsetPtr);
126 *OffsetPtr += size;
127 return true;
128 }
129 case DW_FORM_block2: {
130 uint16_t size = DebugInfoData.getU16(OffsetPtr);
131 *OffsetPtr += size;
132 return true;
133 }
134 case DW_FORM_block4: {
135 uint32_t size = DebugInfoData.getU32(OffsetPtr);
136 *OffsetPtr += size;
137 return true;
138 }
139
140 // Inlined NULL terminated C-strings.
141 case DW_FORM_string:
142 DebugInfoData.getCStr(OffsetPtr);
143 return true;
144
145 case DW_FORM_addr:
146 case DW_FORM_ref_addr:
147 case DW_FORM_flag_present:
148 case DW_FORM_data1:
149 case DW_FORM_data2:
150 case DW_FORM_data4:
151 case DW_FORM_data8:
152 case DW_FORM_data16:
153 case DW_FORM_flag:
154 case DW_FORM_ref1:
155 case DW_FORM_ref2:
156 case DW_FORM_ref4:
157 case DW_FORM_ref8:
158 case DW_FORM_ref_sig8:
159 case DW_FORM_ref_sup4:
160 case DW_FORM_ref_sup8:
161 case DW_FORM_strx1:
162 case DW_FORM_strx2:
163 case DW_FORM_strx3:
164 case DW_FORM_strx4:
165 case DW_FORM_addrx1:
166 case DW_FORM_addrx2:
167 case DW_FORM_addrx3:
168 case DW_FORM_addrx4:
169 case DW_FORM_sec_offset:
170 case DW_FORM_strp:
171 case DW_FORM_strp_sup:
172 case DW_FORM_line_strp:
173 case DW_FORM_GNU_ref_alt:
174 case DW_FORM_GNU_strp_alt:
175 case DW_FORM_implicit_const:
176 if (std::optional<uint8_t> FixedSize =
177 dwarf::getFixedFormByteSize(Form, Params)) {
178 *OffsetPtr += *FixedSize;
179 return true;
180 }
181 return false;
182
183 // signed or unsigned LEB 128 values.
184 case DW_FORM_sdata:
185 DebugInfoData.getSLEB128(OffsetPtr);
186 return true;
187
188 case DW_FORM_udata:
189 case DW_FORM_ref_udata:
190 case DW_FORM_strx:
191 case DW_FORM_addrx:
192 case DW_FORM_loclistx:
193 case DW_FORM_rnglistx:
194 case DW_FORM_GNU_addr_index:
195 case DW_FORM_GNU_str_index:
196 DebugInfoData.getULEB128(OffsetPtr);
197 return true;
198
199 case DW_FORM_LLVM_addrx_offset:
200 DebugInfoData.getULEB128(OffsetPtr);
201 *OffsetPtr += 4;
202 return true;
203
204 case DW_FORM_indirect:
205 Indirect = true;
206 Form = static_cast<dwarf::Form>(DebugInfoData.getULEB128(OffsetPtr));
207 break;
208
209 default:
210 return false;
211 }
212 } while (Indirect);
213 return true;
214 }
215
isFormClass(DWARFFormValue::FormClass FC) const216 bool DWARFFormValue::isFormClass(DWARFFormValue::FormClass FC) const {
217 return doesFormBelongToClass(Form, FC, U ? U->getVersion() : 3);
218 }
219
extractValue(const DWARFDataExtractor & Data,uint64_t * OffsetPtr,dwarf::FormParams FP,const DWARFContext * Ctx,const DWARFUnit * CU)220 bool DWARFFormValue::extractValue(const DWARFDataExtractor &Data,
221 uint64_t *OffsetPtr, dwarf::FormParams FP,
222 const DWARFContext *Ctx,
223 const DWARFUnit *CU) {
224 if (!Ctx && CU)
225 Ctx = &CU->getContext();
226 C = Ctx;
227 U = CU;
228 Format = FP.Format;
229 bool Indirect = false;
230 bool IsBlock = false;
231 Value.data = nullptr;
232 // Read the value for the form into value and follow and DW_FORM_indirect
233 // instances we run into
234 Error Err = Error::success();
235 do {
236 Indirect = false;
237 switch (Form) {
238 case DW_FORM_addr:
239 case DW_FORM_ref_addr: {
240 uint16_t Size =
241 (Form == DW_FORM_addr) ? FP.AddrSize : FP.getRefAddrByteSize();
242 Value.uval =
243 Data.getRelocatedValue(Size, OffsetPtr, &Value.SectionIndex, &Err);
244 break;
245 }
246 case DW_FORM_exprloc:
247 case DW_FORM_block:
248 Value.uval = Data.getULEB128(OffsetPtr, &Err);
249 IsBlock = true;
250 break;
251 case DW_FORM_block1:
252 Value.uval = Data.getU8(OffsetPtr, &Err);
253 IsBlock = true;
254 break;
255 case DW_FORM_block2:
256 Value.uval = Data.getU16(OffsetPtr, &Err);
257 IsBlock = true;
258 break;
259 case DW_FORM_block4:
260 Value.uval = Data.getU32(OffsetPtr, &Err);
261 IsBlock = true;
262 break;
263 case DW_FORM_data1:
264 case DW_FORM_ref1:
265 case DW_FORM_flag:
266 case DW_FORM_strx1:
267 case DW_FORM_addrx1:
268 Value.uval = Data.getU8(OffsetPtr, &Err);
269 break;
270 case DW_FORM_data2:
271 case DW_FORM_ref2:
272 case DW_FORM_strx2:
273 case DW_FORM_addrx2:
274 Value.uval = Data.getU16(OffsetPtr, &Err);
275 break;
276 case DW_FORM_strx3:
277 case DW_FORM_addrx3:
278 Value.uval = Data.getU24(OffsetPtr, &Err);
279 break;
280 case DW_FORM_data4:
281 case DW_FORM_ref4:
282 case DW_FORM_ref_sup4:
283 case DW_FORM_strx4:
284 case DW_FORM_addrx4:
285 Value.uval = Data.getRelocatedValue(4, OffsetPtr, nullptr, &Err);
286 break;
287 case DW_FORM_data8:
288 case DW_FORM_ref8:
289 case DW_FORM_ref_sup8:
290 Value.uval = Data.getRelocatedValue(8, OffsetPtr, nullptr, &Err);
291 break;
292 case DW_FORM_data16:
293 // Treat this like a 16-byte block.
294 Value.uval = 16;
295 IsBlock = true;
296 break;
297 case DW_FORM_sdata:
298 Value.sval = Data.getSLEB128(OffsetPtr, &Err);
299 break;
300 case DW_FORM_udata:
301 case DW_FORM_ref_udata:
302 case DW_FORM_rnglistx:
303 case DW_FORM_loclistx:
304 case DW_FORM_GNU_addr_index:
305 case DW_FORM_GNU_str_index:
306 case DW_FORM_addrx:
307 case DW_FORM_strx:
308 Value.uval = Data.getULEB128(OffsetPtr, &Err);
309 break;
310 case DW_FORM_LLVM_addrx_offset:
311 Value.uval = Data.getULEB128(OffsetPtr, &Err) << 32;
312 Value.uval |= Data.getU32(OffsetPtr, &Err);
313 break;
314 case DW_FORM_string:
315 Value.cstr = Data.getCStr(OffsetPtr, &Err);
316 break;
317 case DW_FORM_indirect:
318 Form = static_cast<dwarf::Form>(Data.getULEB128(OffsetPtr, &Err));
319 Indirect = true;
320 break;
321 case DW_FORM_strp:
322 case DW_FORM_sec_offset:
323 case DW_FORM_GNU_ref_alt:
324 case DW_FORM_GNU_strp_alt:
325 case DW_FORM_line_strp:
326 case DW_FORM_strp_sup: {
327 Value.uval = Data.getRelocatedValue(FP.getDwarfOffsetByteSize(),
328 OffsetPtr, nullptr, &Err);
329 break;
330 }
331 case DW_FORM_flag_present:
332 Value.uval = 1;
333 break;
334 case DW_FORM_ref_sig8:
335 Value.uval = Data.getU64(OffsetPtr, &Err);
336 break;
337 case DW_FORM_implicit_const:
338 // Value has been already set by DWARFFormValue::createFromSValue.
339 break;
340 default:
341 // DWARFFormValue::skipValue() will have caught this and caused all
342 // DWARF DIEs to fail to be parsed, so this code is not be reachable.
343 llvm_unreachable("unsupported form");
344 }
345 } while (Indirect && !Err);
346
347 if (IsBlock)
348 Value.data = Data.getBytes(OffsetPtr, Value.uval, &Err).bytes_begin();
349
350 return !errorToBool(std::move(Err));
351 }
352
dumpAddress(raw_ostream & OS,uint8_t AddressSize,uint64_t Address)353 void DWARFFormValue::dumpAddress(raw_ostream &OS, uint8_t AddressSize,
354 uint64_t Address) {
355 uint8_t HexDigits = AddressSize * 2;
356 OS << format("0x%*.*" PRIx64, HexDigits, HexDigits, Address);
357 }
358
dumpSectionedAddress(raw_ostream & OS,DIDumpOptions DumpOpts,object::SectionedAddress SA) const359 void DWARFFormValue::dumpSectionedAddress(raw_ostream &OS,
360 DIDumpOptions DumpOpts,
361 object::SectionedAddress SA) const {
362 dumpAddress(OS, U->getAddressByteSize(), SA.Address);
363 dumpAddressSection(U->getContext().getDWARFObj(), OS, DumpOpts,
364 SA.SectionIndex);
365 }
366
dumpAddressSection(const DWARFObject & Obj,raw_ostream & OS,DIDumpOptions DumpOpts,uint64_t SectionIndex)367 void DWARFFormValue::dumpAddressSection(const DWARFObject &Obj, raw_ostream &OS,
368 DIDumpOptions DumpOpts,
369 uint64_t SectionIndex) {
370 if (!DumpOpts.Verbose || SectionIndex == -1ULL)
371 return;
372 ArrayRef<SectionName> SectionNames = Obj.getSectionNames();
373 const auto &SecRef = SectionNames[SectionIndex];
374
375 OS << " \"" << SecRef.Name << '\"';
376
377 // Print section index if name is not unique.
378 if (!SecRef.IsNameUnique)
379 OS << format(" [%" PRIu64 "]", SectionIndex);
380 }
381
dump(raw_ostream & OS,DIDumpOptions DumpOpts) const382 void DWARFFormValue::dump(raw_ostream &OS, DIDumpOptions DumpOpts) const {
383 uint64_t UValue = Value.uval;
384 bool CURelativeOffset = false;
385 raw_ostream &AddrOS = DumpOpts.ShowAddresses
386 ? WithColor(OS, HighlightColor::Address).get()
387 : nulls();
388 int OffsetDumpWidth = 2 * dwarf::getDwarfOffsetByteSize(Format);
389 switch (Form) {
390 case DW_FORM_addr:
391 dumpSectionedAddress(AddrOS, DumpOpts, {Value.uval, Value.SectionIndex});
392 break;
393 case DW_FORM_addrx:
394 case DW_FORM_addrx1:
395 case DW_FORM_addrx2:
396 case DW_FORM_addrx3:
397 case DW_FORM_addrx4:
398 case DW_FORM_GNU_addr_index:
399 case DW_FORM_LLVM_addrx_offset: {
400 if (U == nullptr) {
401 OS << "<invalid dwarf unit>";
402 break;
403 }
404 std::optional<object::SectionedAddress> A = getAsSectionedAddress();
405 if (!A || DumpOpts.Verbose) {
406 if (Form == DW_FORM_LLVM_addrx_offset) {
407 uint32_t Index = UValue >> 32;
408 uint32_t Offset = UValue & 0xffffffff;
409 AddrOS << format("indexed (%8.8x) + 0x%x address = ", Index, Offset);
410 } else
411 AddrOS << format("indexed (%8.8x) address = ", (uint32_t)UValue);
412 }
413 if (A)
414 dumpSectionedAddress(AddrOS, DumpOpts, *A);
415 else
416 OS << "<unresolved>";
417 break;
418 }
419 case DW_FORM_flag_present:
420 OS << "true";
421 break;
422 case DW_FORM_flag:
423 case DW_FORM_data1:
424 OS << format("0x%02x", (uint8_t)UValue);
425 break;
426 case DW_FORM_data2:
427 OS << format("0x%04x", (uint16_t)UValue);
428 break;
429 case DW_FORM_data4:
430 OS << format("0x%08x", (uint32_t)UValue);
431 break;
432 case DW_FORM_ref_sig8:
433 AddrOS << format("0x%016" PRIx64, UValue);
434 break;
435 case DW_FORM_data8:
436 OS << format("0x%016" PRIx64, UValue);
437 break;
438 case DW_FORM_data16:
439 OS << format_bytes(ArrayRef<uint8_t>(Value.data, 16), std::nullopt, 16, 16);
440 break;
441 case DW_FORM_string:
442 OS << '"';
443 OS.write_escaped(Value.cstr);
444 OS << '"';
445 break;
446 case DW_FORM_exprloc:
447 case DW_FORM_block:
448 case DW_FORM_block1:
449 case DW_FORM_block2:
450 case DW_FORM_block4:
451 if (UValue > 0) {
452 switch (Form) {
453 case DW_FORM_exprloc:
454 case DW_FORM_block:
455 AddrOS << format("<0x%" PRIx64 "> ", UValue);
456 break;
457 case DW_FORM_block1:
458 AddrOS << format("<0x%2.2x> ", (uint8_t)UValue);
459 break;
460 case DW_FORM_block2:
461 AddrOS << format("<0x%4.4x> ", (uint16_t)UValue);
462 break;
463 case DW_FORM_block4:
464 AddrOS << format("<0x%8.8x> ", (uint32_t)UValue);
465 break;
466 default:
467 break;
468 }
469
470 const uint8_t *DataPtr = Value.data;
471 if (DataPtr) {
472 // UValue contains size of block
473 const uint8_t *EndDataPtr = DataPtr + UValue;
474 while (DataPtr < EndDataPtr) {
475 AddrOS << format("%2.2x ", *DataPtr);
476 ++DataPtr;
477 }
478 } else
479 OS << "NULL";
480 }
481 break;
482
483 case DW_FORM_sdata:
484 case DW_FORM_implicit_const:
485 OS << Value.sval;
486 break;
487 case DW_FORM_udata:
488 OS << Value.uval;
489 break;
490 case DW_FORM_strp:
491 if (DumpOpts.Verbose)
492 OS << format(" .debug_str[0x%0*" PRIx64 "] = ", OffsetDumpWidth, UValue);
493 dumpString(OS);
494 break;
495 case DW_FORM_line_strp:
496 if (DumpOpts.Verbose)
497 OS << format(" .debug_line_str[0x%0*" PRIx64 "] = ", OffsetDumpWidth,
498 UValue);
499 dumpString(OS);
500 break;
501 case DW_FORM_strx:
502 case DW_FORM_strx1:
503 case DW_FORM_strx2:
504 case DW_FORM_strx3:
505 case DW_FORM_strx4:
506 case DW_FORM_GNU_str_index:
507 if (DumpOpts.Verbose)
508 OS << format("indexed (%8.8x) string = ", (uint32_t)UValue);
509 dumpString(OS);
510 break;
511 case DW_FORM_GNU_strp_alt:
512 if (DumpOpts.Verbose)
513 OS << format("alt indirect string, offset: 0x%" PRIx64 "", UValue);
514 dumpString(OS);
515 break;
516 case DW_FORM_ref_addr:
517 AddrOS << format("0x%016" PRIx64, UValue);
518 break;
519 case DW_FORM_ref1:
520 CURelativeOffset = true;
521 if (DumpOpts.Verbose)
522 AddrOS << format("cu + 0x%2.2x", (uint8_t)UValue);
523 break;
524 case DW_FORM_ref2:
525 CURelativeOffset = true;
526 if (DumpOpts.Verbose)
527 AddrOS << format("cu + 0x%4.4x", (uint16_t)UValue);
528 break;
529 case DW_FORM_ref4:
530 CURelativeOffset = true;
531 if (DumpOpts.Verbose)
532 AddrOS << format("cu + 0x%4.4x", (uint32_t)UValue);
533 break;
534 case DW_FORM_ref8:
535 CURelativeOffset = true;
536 if (DumpOpts.Verbose)
537 AddrOS << format("cu + 0x%8.8" PRIx64, UValue);
538 break;
539 case DW_FORM_ref_udata:
540 CURelativeOffset = true;
541 if (DumpOpts.Verbose)
542 AddrOS << format("cu + 0x%" PRIx64, UValue);
543 break;
544 case DW_FORM_GNU_ref_alt:
545 AddrOS << format("<alt 0x%" PRIx64 ">", UValue);
546 break;
547
548 // All DW_FORM_indirect attributes should be resolved prior to calling
549 // this function
550 case DW_FORM_indirect:
551 OS << "DW_FORM_indirect";
552 break;
553
554 case DW_FORM_rnglistx:
555 OS << format("indexed (0x%x) rangelist = ", (uint32_t)UValue);
556 break;
557
558 case DW_FORM_loclistx:
559 OS << format("indexed (0x%x) loclist = ", (uint32_t)UValue);
560 break;
561
562 case DW_FORM_sec_offset:
563 AddrOS << format("0x%0*" PRIx64, OffsetDumpWidth, UValue);
564 break;
565
566 default:
567 OS << format("DW_FORM(0x%4.4x)", Form);
568 break;
569 }
570
571 if (CURelativeOffset) {
572 if (DumpOpts.Verbose)
573 OS << " => {";
574 if (DumpOpts.ShowAddresses)
575 WithColor(OS, HighlightColor::Address).get()
576 << format("0x%8.8" PRIx64, UValue + (U ? U->getOffset() : 0));
577 if (DumpOpts.Verbose)
578 OS << "}";
579 }
580 }
581
dumpString(raw_ostream & OS) const582 void DWARFFormValue::dumpString(raw_ostream &OS) const {
583 if (auto DbgStr = dwarf::toString(*this)) {
584 auto COS = WithColor(OS, HighlightColor::String);
585 COS.get() << '"';
586 COS.get().write_escaped(*DbgStr);
587 COS.get() << '"';
588 }
589 }
590
getAsCString() const591 Expected<const char *> DWARFFormValue::getAsCString() const {
592 if (!isFormClass(FC_String))
593 return make_error<StringError>("Invalid form for string attribute",
594 inconvertibleErrorCode());
595 if (Form == DW_FORM_string)
596 return Value.cstr;
597 // FIXME: Add support for DW_FORM_GNU_strp_alt
598 if (Form == DW_FORM_GNU_strp_alt || C == nullptr)
599 return make_error<StringError>("Unsupported form for string attribute",
600 inconvertibleErrorCode());
601 uint64_t Offset = Value.uval;
602 std::optional<uint32_t> Index;
603 if (Form == DW_FORM_GNU_str_index || Form == DW_FORM_strx ||
604 Form == DW_FORM_strx1 || Form == DW_FORM_strx2 || Form == DW_FORM_strx3 ||
605 Form == DW_FORM_strx4) {
606 if (!U)
607 return make_error<StringError>("API limitation - string extraction not "
608 "available without a DWARFUnit",
609 inconvertibleErrorCode());
610 Expected<uint64_t> StrOffset = U->getStringOffsetSectionItem(Offset);
611 Index = Offset;
612 if (!StrOffset)
613 return StrOffset.takeError();
614 Offset = *StrOffset;
615 }
616 // Prefer the Unit's string extractor, because for .dwo it will point to
617 // .debug_str.dwo, while the Context's extractor always uses .debug_str.
618 bool IsDebugLineString = Form == DW_FORM_line_strp;
619 DataExtractor StrData =
620 IsDebugLineString ? C->getLineStringExtractor()
621 : U ? U->getStringExtractor() : C->getStringExtractor();
622 if (const char *Str = StrData.getCStr(&Offset))
623 return Str;
624 std::string Msg = FormEncodingString(Form).str();
625 if (Index)
626 Msg += (" uses index " + Twine(*Index) + ", but the referenced string").str();
627 Msg += (" offset " + Twine(Offset) + " is beyond " +
628 (IsDebugLineString ? ".debug_line_str" : ".debug_str") + " bounds")
629 .str();
630 return make_error<StringError>(Msg,
631 inconvertibleErrorCode());
632 }
633
getAsAddress() const634 std::optional<uint64_t> DWARFFormValue::getAsAddress() const {
635 if (auto SA = getAsSectionedAddress())
636 return SA->Address;
637 return std::nullopt;
638 }
639
getAsSectionedAddress(const ValueType & Value,const dwarf::Form Form,const DWARFUnit * U)640 std::optional<object::SectionedAddress> DWARFFormValue::getAsSectionedAddress(
641 const ValueType &Value, const dwarf::Form Form, const DWARFUnit *U) {
642 if (!doesFormBelongToClass(Form, FC_Address, U ? U->getVersion() : 3))
643 return std::nullopt;
644 bool AddrOffset = Form == dwarf::DW_FORM_LLVM_addrx_offset;
645 if (Form == DW_FORM_GNU_addr_index || Form == DW_FORM_addrx ||
646 Form == DW_FORM_addrx1 || Form == DW_FORM_addrx2 ||
647 Form == DW_FORM_addrx3 || Form == DW_FORM_addrx4 || AddrOffset) {
648
649 uint32_t Index = AddrOffset ? (Value.uval >> 32) : Value.uval;
650 if (!U)
651 return std::nullopt;
652 std::optional<object::SectionedAddress> SA =
653 U->getAddrOffsetSectionItem(Index);
654 if (!SA)
655 return std::nullopt;
656 if (AddrOffset)
657 SA->Address += (Value.uval & 0xffffffff);
658 return SA;
659 }
660 return {{Value.uval, Value.SectionIndex}};
661 }
662
663 std::optional<object::SectionedAddress>
getAsSectionedAddress() const664 DWARFFormValue::getAsSectionedAddress() const {
665 return getAsSectionedAddress(Value, Form, U);
666 }
667
getAsRelativeReference() const668 std::optional<uint64_t> DWARFFormValue::getAsRelativeReference() const {
669 switch (Form) {
670 case DW_FORM_ref1:
671 case DW_FORM_ref2:
672 case DW_FORM_ref4:
673 case DW_FORM_ref8:
674 case DW_FORM_ref_udata:
675 if (!U)
676 return std::nullopt;
677 return Value.uval;
678 default:
679 return std::nullopt;
680 }
681 }
682
getAsDebugInfoReference() const683 std::optional<uint64_t> DWARFFormValue::getAsDebugInfoReference() const {
684 if (Form == DW_FORM_ref_addr)
685 return Value.uval;
686 return std::nullopt;
687 }
688
getAsSignatureReference() const689 std::optional<uint64_t> DWARFFormValue::getAsSignatureReference() const {
690 if (Form == DW_FORM_ref_sig8)
691 return Value.uval;
692 return std::nullopt;
693 }
694
getAsSupplementaryReference() const695 std::optional<uint64_t> DWARFFormValue::getAsSupplementaryReference() const {
696 switch (Form) {
697 case DW_FORM_GNU_ref_alt:
698 case DW_FORM_ref_sup4:
699 case DW_FORM_ref_sup8:
700 return Value.uval;
701 default:
702 return std::nullopt;
703 }
704 }
705
getAsSectionOffset() const706 std::optional<uint64_t> DWARFFormValue::getAsSectionOffset() const {
707 if (!isFormClass(FC_SectionOffset))
708 return std::nullopt;
709 return Value.uval;
710 }
711
getAsUnsignedConstant() const712 std::optional<uint64_t> DWARFFormValue::getAsUnsignedConstant() const {
713 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) ||
714 Form == DW_FORM_sdata)
715 return std::nullopt;
716 return Value.uval;
717 }
718
getAsSignedConstant() const719 std::optional<int64_t> DWARFFormValue::getAsSignedConstant() const {
720 if ((!isFormClass(FC_Constant) && !isFormClass(FC_Flag)) ||
721 (Form == DW_FORM_udata &&
722 uint64_t(std::numeric_limits<int64_t>::max()) < Value.uval))
723 return std::nullopt;
724 switch (Form) {
725 case DW_FORM_data4:
726 return int32_t(Value.uval);
727 case DW_FORM_data2:
728 return int16_t(Value.uval);
729 case DW_FORM_data1:
730 return int8_t(Value.uval);
731 case DW_FORM_sdata:
732 case DW_FORM_data8:
733 default:
734 return Value.sval;
735 }
736 }
737
getAsBlock() const738 std::optional<ArrayRef<uint8_t>> DWARFFormValue::getAsBlock() const {
739 if (!isFormClass(FC_Block) && !isFormClass(FC_Exprloc) &&
740 Form != DW_FORM_data16)
741 return std::nullopt;
742 return ArrayRef(Value.data, Value.uval);
743 }
744
getAsCStringOffset() const745 std::optional<uint64_t> DWARFFormValue::getAsCStringOffset() const {
746 if (!isFormClass(FC_String) && Form == DW_FORM_string)
747 return std::nullopt;
748 return Value.uval;
749 }
750
getAsReferenceUVal() const751 std::optional<uint64_t> DWARFFormValue::getAsReferenceUVal() const {
752 if (!isFormClass(FC_Reference))
753 return std::nullopt;
754 return Value.uval;
755 }
756
757 std::optional<std::string>
getAsFile(DILineInfoSpecifier::FileLineInfoKind Kind) const758 DWARFFormValue::getAsFile(DILineInfoSpecifier::FileLineInfoKind Kind) const {
759 if (U == nullptr || !isFormClass(FC_Constant))
760 return std::nullopt;
761 DWARFUnit *DLU = const_cast<DWARFUnit *>(U)->getLinkedUnit();
762 if (auto *LT = DLU->getContext().getLineTableForUnit(DLU)) {
763 std::string FileName;
764 if (LT->getFileNameByIndex(Value.uval, DLU->getCompilationDir(), Kind,
765 FileName))
766 return FileName;
767 }
768 return std::nullopt;
769 }
770
doesFormBelongToClass(dwarf::Form Form,DWARFFormValue::FormClass FC,uint16_t DwarfVersion)771 bool llvm::dwarf::doesFormBelongToClass(dwarf::Form Form, DWARFFormValue::FormClass FC,
772 uint16_t DwarfVersion) {
773 // First, check DWARF5 form classes.
774 if (Form < std::size(DWARF5FormClasses) && DWARF5FormClasses[Form] == FC)
775 return true;
776 // Check more forms from extensions and proposals.
777 switch (Form) {
778 case DW_FORM_GNU_ref_alt:
779 return (FC == DWARFFormValue::FC_Reference);
780 case DW_FORM_GNU_addr_index:
781 return (FC == DWARFFormValue::FC_Address);
782 case DW_FORM_GNU_str_index:
783 case DW_FORM_GNU_strp_alt:
784 return (FC == DWARFFormValue::FC_String);
785 case DW_FORM_LLVM_addrx_offset:
786 return (FC == DWARFFormValue::FC_Address);
787 case DW_FORM_strp:
788 case DW_FORM_line_strp:
789 return (FC == DWARFFormValue::FC_SectionOffset);
790 case DW_FORM_data4:
791 case DW_FORM_data8:
792 // In DWARF3 DW_FORM_data4 and DW_FORM_data8 served also as a section
793 // offset.
794 return (FC == DWARFFormValue::FC_SectionOffset) && (DwarfVersion <= 3);
795 default:
796 return false;
797 }
798 }
799