xref: /llvm-project/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp (revision 8c6996f737fe941ce58366183c6bda2282b3054d)
1 //===-- ObjectFileELF.cpp ------------------------------------- -*- C++ -*-===//
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 "ObjectFileELF.h"
11 
12 #include <cassert>
13 #include <algorithm>
14 #include <unordered_map>
15 
16 #include "lldb/Core/ArchSpec.h"
17 #include "lldb/Core/DataBuffer.h"
18 #include "lldb/Core/Error.h"
19 #include "lldb/Core/FileSpecList.h"
20 #include "lldb/Core/Log.h"
21 #include "lldb/Core/Module.h"
22 #include "lldb/Core/ModuleSpec.h"
23 #include "lldb/Core/PluginManager.h"
24 #include "lldb/Core/Section.h"
25 #include "lldb/Core/Stream.h"
26 #include "lldb/Core/Timer.h"
27 #include "lldb/Symbol/DWARFCallFrameInfo.h"
28 #include "lldb/Symbol/SymbolContext.h"
29 #include "lldb/Target/SectionLoadList.h"
30 #include "lldb/Target/Target.h"
31 
32 #include "llvm/ADT/PointerUnion.h"
33 #include "llvm/ADT/StringRef.h"
34 #include "llvm/Support/MathExtras.h"
35 
36 #define CASE_AND_STREAM(s, def, width)                  \
37     case def: s->Printf("%-*s", width, #def); break;
38 
39 using namespace lldb;
40 using namespace lldb_private;
41 using namespace elf;
42 using namespace llvm::ELF;
43 
44 namespace {
45 
46 // ELF note owner definitions
47 const char *const LLDB_NT_OWNER_FREEBSD = "FreeBSD";
48 const char *const LLDB_NT_OWNER_GNU     = "GNU";
49 const char *const LLDB_NT_OWNER_NETBSD  = "NetBSD";
50 const char *const LLDB_NT_OWNER_CSR     = "csr";
51 const char *const LLDB_NT_OWNER_ANDROID = "Android";
52 const char *const LLDB_NT_OWNER_CORE    = "CORE";
53 const char *const LLDB_NT_OWNER_LINUX   = "LINUX";
54 
55 // ELF note type definitions
56 const elf_word LLDB_NT_FREEBSD_ABI_TAG  = 0x01;
57 const elf_word LLDB_NT_FREEBSD_ABI_SIZE = 4;
58 
59 const elf_word LLDB_NT_GNU_ABI_TAG      = 0x01;
60 const elf_word LLDB_NT_GNU_ABI_SIZE     = 16;
61 
62 const elf_word LLDB_NT_GNU_BUILD_ID_TAG = 0x03;
63 
64 const elf_word LLDB_NT_NETBSD_ABI_TAG   = 0x01;
65 const elf_word LLDB_NT_NETBSD_ABI_SIZE  = 4;
66 
67 // GNU ABI note OS constants
68 const elf_word LLDB_NT_GNU_ABI_OS_LINUX   = 0x00;
69 const elf_word LLDB_NT_GNU_ABI_OS_HURD    = 0x01;
70 const elf_word LLDB_NT_GNU_ABI_OS_SOLARIS = 0x02;
71 
72 // LLDB_NT_OWNER_CORE and LLDB_NT_OWNER_LINUX note contants
73 #define NT_PRSTATUS             1
74 #define NT_PRFPREG              2
75 #define NT_PRPSINFO             3
76 #define NT_TASKSTRUCT           4
77 #define NT_AUXV                 6
78 #define NT_SIGINFO              0x53494749
79 #define NT_FILE                 0x46494c45
80 #define NT_PRXFPREG             0x46e62b7f
81 #define NT_PPC_VMX              0x100
82 #define NT_PPC_SPE              0x101
83 #define NT_PPC_VSX              0x102
84 #define NT_386_TLS              0x200
85 #define NT_386_IOPERM           0x201
86 #define NT_X86_XSTATE           0x202
87 #define NT_S390_HIGH_GPRS       0x300
88 #define NT_S390_TIMER           0x301
89 #define NT_S390_TODCMP          0x302
90 #define NT_S390_TODPREG         0x303
91 #define NT_S390_CTRS            0x304
92 #define NT_S390_PREFIX          0x305
93 #define NT_S390_LAST_BREAK      0x306
94 #define NT_S390_SYSTEM_CALL     0x307
95 #define NT_S390_TDB             0x308
96 #define NT_S390_VXRS_LOW        0x309
97 #define NT_S390_VXRS_HIGH       0x30a
98 #define NT_ARM_VFP              0x400
99 #define NT_ARM_TLS              0x401
100 #define NT_ARM_HW_BREAK         0x402
101 #define NT_ARM_HW_WATCH         0x403
102 #define NT_ARM_SYSTEM_CALL      0x404
103 #define NT_METAG_CBUF           0x500
104 #define NT_METAG_RPIPE          0x501
105 #define NT_METAG_TLS            0x502
106 
107 //===----------------------------------------------------------------------===//
108 /// @class ELFRelocation
109 /// @brief Generic wrapper for ELFRel and ELFRela.
110 ///
111 /// This helper class allows us to parse both ELFRel and ELFRela relocation
112 /// entries in a generic manner.
113 class ELFRelocation
114 {
115 public:
116 
117     /// Constructs an ELFRelocation entry with a personality as given by @p
118     /// type.
119     ///
120     /// @param type Either DT_REL or DT_RELA.  Any other value is invalid.
121     ELFRelocation(unsigned type);
122 
123     ~ELFRelocation();
124 
125     bool
126     Parse(const lldb_private::DataExtractor &data, lldb::offset_t *offset);
127 
128     static unsigned
129     RelocType32(const ELFRelocation &rel);
130 
131     static unsigned
132     RelocType64(const ELFRelocation &rel);
133 
134     static unsigned
135     RelocSymbol32(const ELFRelocation &rel);
136 
137     static unsigned
138     RelocSymbol64(const ELFRelocation &rel);
139 
140     static unsigned
141     RelocOffset32(const ELFRelocation &rel);
142 
143     static unsigned
144     RelocOffset64(const ELFRelocation &rel);
145 
146     static unsigned
147     RelocAddend32(const ELFRelocation &rel);
148 
149     static unsigned
150     RelocAddend64(const ELFRelocation &rel);
151 
152 private:
153     typedef llvm::PointerUnion<ELFRel*, ELFRela*> RelocUnion;
154 
155     RelocUnion reloc;
156 };
157 
158 ELFRelocation::ELFRelocation(unsigned type)
159 {
160     if (type == DT_REL || type == SHT_REL)
161         reloc = new ELFRel();
162     else if (type == DT_RELA || type == SHT_RELA)
163         reloc = new ELFRela();
164     else {
165         assert(false && "unexpected relocation type");
166         reloc = static_cast<ELFRel*>(NULL);
167     }
168 }
169 
170 ELFRelocation::~ELFRelocation()
171 {
172     if (reloc.is<ELFRel*>())
173         delete reloc.get<ELFRel*>();
174     else
175         delete reloc.get<ELFRela*>();
176 }
177 
178 bool
179 ELFRelocation::Parse(const lldb_private::DataExtractor &data, lldb::offset_t *offset)
180 {
181     if (reloc.is<ELFRel*>())
182         return reloc.get<ELFRel*>()->Parse(data, offset);
183     else
184         return reloc.get<ELFRela*>()->Parse(data, offset);
185 }
186 
187 unsigned
188 ELFRelocation::RelocType32(const ELFRelocation &rel)
189 {
190     if (rel.reloc.is<ELFRel*>())
191         return ELFRel::RelocType32(*rel.reloc.get<ELFRel*>());
192     else
193         return ELFRela::RelocType32(*rel.reloc.get<ELFRela*>());
194 }
195 
196 unsigned
197 ELFRelocation::RelocType64(const ELFRelocation &rel)
198 {
199     if (rel.reloc.is<ELFRel*>())
200         return ELFRel::RelocType64(*rel.reloc.get<ELFRel*>());
201     else
202         return ELFRela::RelocType64(*rel.reloc.get<ELFRela*>());
203 }
204 
205 unsigned
206 ELFRelocation::RelocSymbol32(const ELFRelocation &rel)
207 {
208     if (rel.reloc.is<ELFRel*>())
209         return ELFRel::RelocSymbol32(*rel.reloc.get<ELFRel*>());
210     else
211         return ELFRela::RelocSymbol32(*rel.reloc.get<ELFRela*>());
212 }
213 
214 unsigned
215 ELFRelocation::RelocSymbol64(const ELFRelocation &rel)
216 {
217     if (rel.reloc.is<ELFRel*>())
218         return ELFRel::RelocSymbol64(*rel.reloc.get<ELFRel*>());
219     else
220         return ELFRela::RelocSymbol64(*rel.reloc.get<ELFRela*>());
221 }
222 
223 unsigned
224 ELFRelocation::RelocOffset32(const ELFRelocation &rel)
225 {
226     if (rel.reloc.is<ELFRel*>())
227         return rel.reloc.get<ELFRel*>()->r_offset;
228     else
229         return rel.reloc.get<ELFRela*>()->r_offset;
230 }
231 
232 unsigned
233 ELFRelocation::RelocOffset64(const ELFRelocation &rel)
234 {
235     if (rel.reloc.is<ELFRel*>())
236         return rel.reloc.get<ELFRel*>()->r_offset;
237     else
238         return rel.reloc.get<ELFRela*>()->r_offset;
239 }
240 
241 unsigned
242 ELFRelocation::RelocAddend32(const ELFRelocation &rel)
243 {
244     if (rel.reloc.is<ELFRel*>())
245         return 0;
246     else
247         return rel.reloc.get<ELFRela*>()->r_addend;
248 }
249 
250 unsigned
251 ELFRelocation::RelocAddend64(const ELFRelocation &rel)
252 {
253     if (rel.reloc.is<ELFRel*>())
254         return 0;
255     else
256         return rel.reloc.get<ELFRela*>()->r_addend;
257 }
258 
259 } // end anonymous namespace
260 
261 bool
262 ELFNote::Parse(const DataExtractor &data, lldb::offset_t *offset)
263 {
264     // Read all fields.
265     if (data.GetU32(offset, &n_namesz, 3) == NULL)
266         return false;
267 
268     // The name field is required to be nul-terminated, and n_namesz
269     // includes the terminating nul in observed implementations (contrary
270     // to the ELF-64 spec).  A special case is needed for cores generated
271     // by some older Linux versions, which write a note named "CORE"
272     // without a nul terminator and n_namesz = 4.
273     if (n_namesz == 4)
274     {
275         char buf[4];
276         if (data.ExtractBytes (*offset, 4, data.GetByteOrder(), buf) != 4)
277             return false;
278         if (strncmp (buf, "CORE", 4) == 0)
279         {
280             n_name = "CORE";
281             *offset += 4;
282             return true;
283         }
284     }
285 
286     const char *cstr = data.GetCStr(offset, llvm::alignTo (n_namesz, 4));
287     if (cstr == NULL)
288     {
289         Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_SYMBOLS));
290         if (log)
291             log->Printf("Failed to parse note name lacking nul terminator");
292 
293         return false;
294     }
295     n_name = cstr;
296     return true;
297 }
298 
299 static uint32_t
300 kalimbaVariantFromElfFlags(const elf::elf_word e_flags)
301 {
302     const uint32_t dsp_rev = e_flags & 0xFF;
303     uint32_t kal_arch_variant = LLDB_INVALID_CPUTYPE;
304     switch(dsp_rev)
305     {
306         // TODO(mg11) Support more variants
307         case 10:
308             kal_arch_variant = llvm::Triple::KalimbaSubArch_v3;
309             break;
310         case 14:
311             kal_arch_variant = llvm::Triple::KalimbaSubArch_v4;
312             break;
313         case 17:
314         case 20:
315             kal_arch_variant = llvm::Triple::KalimbaSubArch_v5;
316             break;
317         default:
318             break;
319     }
320     return kal_arch_variant;
321 }
322 
323 static uint32_t
324 mipsVariantFromElfFlags(const elf::elf_word e_flags, uint32_t endian)
325 {
326     const uint32_t mips_arch = e_flags & llvm::ELF::EF_MIPS_ARCH;
327     uint32_t arch_variant = ArchSpec::eMIPSSubType_unknown;
328 
329     switch (mips_arch)
330     {
331         case llvm::ELF::EF_MIPS_ARCH_1:
332         case llvm::ELF::EF_MIPS_ARCH_2:
333         case llvm::ELF::EF_MIPS_ARCH_32:
334             return (endian == ELFDATA2LSB) ? ArchSpec::eMIPSSubType_mips32el : ArchSpec::eMIPSSubType_mips32;
335         case llvm::ELF::EF_MIPS_ARCH_32R2:
336             return (endian == ELFDATA2LSB) ? ArchSpec::eMIPSSubType_mips32r2el : ArchSpec::eMIPSSubType_mips32r2;
337         case llvm::ELF::EF_MIPS_ARCH_32R6:
338             return (endian == ELFDATA2LSB) ? ArchSpec::eMIPSSubType_mips32r6el : ArchSpec::eMIPSSubType_mips32r6;
339         case llvm::ELF::EF_MIPS_ARCH_3:
340         case llvm::ELF::EF_MIPS_ARCH_4:
341         case llvm::ELF::EF_MIPS_ARCH_5:
342         case llvm::ELF::EF_MIPS_ARCH_64:
343             return (endian == ELFDATA2LSB) ? ArchSpec::eMIPSSubType_mips64el : ArchSpec::eMIPSSubType_mips64;
344         case llvm::ELF::EF_MIPS_ARCH_64R2:
345             return (endian == ELFDATA2LSB) ? ArchSpec::eMIPSSubType_mips64r2el : ArchSpec::eMIPSSubType_mips64r2;
346         case llvm::ELF::EF_MIPS_ARCH_64R6:
347             return (endian == ELFDATA2LSB) ? ArchSpec::eMIPSSubType_mips64r6el : ArchSpec::eMIPSSubType_mips64r6;
348         default:
349             break;
350     }
351 
352     return arch_variant;
353 }
354 
355 static uint32_t
356 subTypeFromElfHeader(const elf::ELFHeader& header)
357 {
358     if (header.e_machine == llvm::ELF::EM_MIPS)
359         return mipsVariantFromElfFlags (header.e_flags,
360             header.e_ident[EI_DATA]);
361 
362     return
363         llvm::ELF::EM_CSR_KALIMBA == header.e_machine ?
364         kalimbaVariantFromElfFlags(header.e_flags) :
365         LLDB_INVALID_CPUTYPE;
366 }
367 
368 //! The kalimba toolchain identifies a code section as being
369 //! one with the SHT_PROGBITS set in the section sh_type and the top
370 //! bit in the 32-bit address field set.
371 static lldb::SectionType
372 kalimbaSectionType(
373     const elf::ELFHeader& header,
374     const elf::ELFSectionHeader& sect_hdr)
375 {
376     if (llvm::ELF::EM_CSR_KALIMBA != header.e_machine)
377     {
378         return eSectionTypeOther;
379     }
380 
381     if (llvm::ELF::SHT_NOBITS == sect_hdr.sh_type)
382     {
383         return eSectionTypeZeroFill;
384     }
385 
386     if (llvm::ELF::SHT_PROGBITS == sect_hdr.sh_type)
387     {
388         const lldb::addr_t KAL_CODE_BIT = 1 << 31;
389         return KAL_CODE_BIT & sect_hdr.sh_addr ?
390              eSectionTypeCode  : eSectionTypeData;
391     }
392 
393     return eSectionTypeOther;
394 }
395 
396 // Arbitrary constant used as UUID prefix for core files.
397 const uint32_t
398 ObjectFileELF::g_core_uuid_magic(0xE210C);
399 
400 //------------------------------------------------------------------
401 // Static methods.
402 //------------------------------------------------------------------
403 void
404 ObjectFileELF::Initialize()
405 {
406     PluginManager::RegisterPlugin(GetPluginNameStatic(),
407                                   GetPluginDescriptionStatic(),
408                                   CreateInstance,
409                                   CreateMemoryInstance,
410                                   GetModuleSpecifications);
411 }
412 
413 void
414 ObjectFileELF::Terminate()
415 {
416     PluginManager::UnregisterPlugin(CreateInstance);
417 }
418 
419 lldb_private::ConstString
420 ObjectFileELF::GetPluginNameStatic()
421 {
422     static ConstString g_name("elf");
423     return g_name;
424 }
425 
426 const char *
427 ObjectFileELF::GetPluginDescriptionStatic()
428 {
429     return "ELF object file reader.";
430 }
431 
432 ObjectFile *
433 ObjectFileELF::CreateInstance (const lldb::ModuleSP &module_sp,
434                                DataBufferSP &data_sp,
435                                lldb::offset_t data_offset,
436                                const lldb_private::FileSpec* file,
437                                lldb::offset_t file_offset,
438                                lldb::offset_t length)
439 {
440     if (!data_sp)
441     {
442         data_sp = file->MemoryMapFileContentsIfLocal(file_offset, length);
443         data_offset = 0;
444     }
445 
446     if (data_sp && data_sp->GetByteSize() > (llvm::ELF::EI_NIDENT + data_offset))
447     {
448         const uint8_t *magic = data_sp->GetBytes() + data_offset;
449         if (ELFHeader::MagicBytesMatch(magic))
450         {
451             // Update the data to contain the entire file if it doesn't already
452             if (data_sp->GetByteSize() < length) {
453                 data_sp = file->MemoryMapFileContentsIfLocal(file_offset, length);
454                 data_offset = 0;
455                 magic = data_sp->GetBytes();
456             }
457             unsigned address_size = ELFHeader::AddressSizeInBytes(magic);
458             if (address_size == 4 || address_size == 8)
459             {
460                 std::unique_ptr<ObjectFileELF> objfile_ap(new ObjectFileELF(module_sp, data_sp, data_offset, file, file_offset, length));
461                 ArchSpec spec;
462                 if (objfile_ap->GetArchitecture(spec) &&
463                     objfile_ap->SetModulesArchitecture(spec))
464                     return objfile_ap.release();
465             }
466         }
467     }
468     return NULL;
469 }
470 
471 
472 ObjectFile*
473 ObjectFileELF::CreateMemoryInstance (const lldb::ModuleSP &module_sp,
474                                      DataBufferSP& data_sp,
475                                      const lldb::ProcessSP &process_sp,
476                                      lldb::addr_t header_addr)
477 {
478     if (data_sp && data_sp->GetByteSize() > (llvm::ELF::EI_NIDENT))
479     {
480         const uint8_t *magic = data_sp->GetBytes();
481         if (ELFHeader::MagicBytesMatch(magic))
482         {
483             unsigned address_size = ELFHeader::AddressSizeInBytes(magic);
484             if (address_size == 4 || address_size == 8)
485             {
486                 std::auto_ptr<ObjectFileELF> objfile_ap(new ObjectFileELF(module_sp, data_sp, process_sp, header_addr));
487                 ArchSpec spec;
488                 if (objfile_ap->GetArchitecture(spec) &&
489                     objfile_ap->SetModulesArchitecture(spec))
490                     return objfile_ap.release();
491             }
492         }
493     }
494     return NULL;
495 }
496 
497 bool
498 ObjectFileELF::MagicBytesMatch (DataBufferSP& data_sp,
499                                   lldb::addr_t data_offset,
500                                   lldb::addr_t data_length)
501 {
502     if (data_sp && data_sp->GetByteSize() > (llvm::ELF::EI_NIDENT + data_offset))
503     {
504         const uint8_t *magic = data_sp->GetBytes() + data_offset;
505         return ELFHeader::MagicBytesMatch(magic);
506     }
507     return false;
508 }
509 
510 /*
511  * crc function from http://svnweb.freebsd.org/base/head/sys/libkern/crc32.c
512  *
513  *   COPYRIGHT (C) 1986 Gary S. Brown. You may use this program, or
514  *   code or tables extracted from it, as desired without restriction.
515  */
516 static uint32_t
517 calc_crc32(uint32_t crc, const void *buf, size_t size)
518 {
519     static const uint32_t g_crc32_tab[] =
520     {
521         0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
522         0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
523         0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
524         0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
525         0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
526         0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
527         0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
528         0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
529         0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
530         0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
531         0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
532         0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
533         0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
534         0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
535         0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
536         0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
537         0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
538         0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
539         0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
540         0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
541         0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
542         0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
543         0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
544         0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
545         0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
546         0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
547         0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
548         0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
549         0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
550         0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
551         0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
552         0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
553         0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
554         0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
555         0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
556         0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
557         0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
558         0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
559         0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
560         0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
561         0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
562         0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
563         0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
564     };
565     const uint8_t *p = (const uint8_t *)buf;
566 
567     crc = crc ^ ~0U;
568     while (size--)
569         crc = g_crc32_tab[(crc ^ *p++) & 0xFF] ^ (crc >> 8);
570     return crc ^ ~0U;
571 }
572 
573 static uint32_t
574 calc_gnu_debuglink_crc32(const void *buf, size_t size)
575 {
576     return calc_crc32(0U, buf, size);
577 }
578 
579 uint32_t
580 ObjectFileELF::CalculateELFNotesSegmentsCRC32 (const ProgramHeaderColl& program_headers,
581                                                DataExtractor& object_data)
582 {
583     typedef ProgramHeaderCollConstIter Iter;
584 
585     uint32_t core_notes_crc = 0;
586 
587     for (Iter I = program_headers.begin(); I != program_headers.end(); ++I)
588     {
589         if (I->p_type == llvm::ELF::PT_NOTE)
590         {
591             const elf_off ph_offset = I->p_offset;
592             const size_t ph_size = I->p_filesz;
593 
594             DataExtractor segment_data;
595             if (segment_data.SetData(object_data, ph_offset, ph_size) != ph_size)
596             {
597                 // The ELF program header contained incorrect data,
598                 // probably corefile is incomplete or corrupted.
599                 break;
600             }
601 
602             core_notes_crc = calc_crc32(core_notes_crc,
603                                         segment_data.GetDataStart(),
604                                         segment_data.GetByteSize());
605         }
606     }
607 
608     return core_notes_crc;
609 }
610 
611 static const char*
612 OSABIAsCString (unsigned char osabi_byte)
613 {
614 #define _MAKE_OSABI_CASE(x) case x: return #x
615     switch (osabi_byte)
616     {
617         _MAKE_OSABI_CASE(ELFOSABI_NONE);
618         _MAKE_OSABI_CASE(ELFOSABI_HPUX);
619         _MAKE_OSABI_CASE(ELFOSABI_NETBSD);
620         _MAKE_OSABI_CASE(ELFOSABI_GNU);
621         _MAKE_OSABI_CASE(ELFOSABI_HURD);
622         _MAKE_OSABI_CASE(ELFOSABI_SOLARIS);
623         _MAKE_OSABI_CASE(ELFOSABI_AIX);
624         _MAKE_OSABI_CASE(ELFOSABI_IRIX);
625         _MAKE_OSABI_CASE(ELFOSABI_FREEBSD);
626         _MAKE_OSABI_CASE(ELFOSABI_TRU64);
627         _MAKE_OSABI_CASE(ELFOSABI_MODESTO);
628         _MAKE_OSABI_CASE(ELFOSABI_OPENBSD);
629         _MAKE_OSABI_CASE(ELFOSABI_OPENVMS);
630         _MAKE_OSABI_CASE(ELFOSABI_NSK);
631         _MAKE_OSABI_CASE(ELFOSABI_AROS);
632         _MAKE_OSABI_CASE(ELFOSABI_FENIXOS);
633         _MAKE_OSABI_CASE(ELFOSABI_C6000_ELFABI);
634         _MAKE_OSABI_CASE(ELFOSABI_C6000_LINUX);
635         _MAKE_OSABI_CASE(ELFOSABI_ARM);
636         _MAKE_OSABI_CASE(ELFOSABI_STANDALONE);
637         default:
638             return "<unknown-osabi>";
639     }
640 #undef _MAKE_OSABI_CASE
641 }
642 
643 //
644 // WARNING : This function is being deprecated
645 // It's functionality has moved to ArchSpec::SetArchitecture
646 // This function is only being kept to validate the move.
647 //
648 // TODO : Remove this function
649 static bool
650 GetOsFromOSABI (unsigned char osabi_byte, llvm::Triple::OSType &ostype)
651 {
652     switch (osabi_byte)
653     {
654         case ELFOSABI_AIX:      ostype = llvm::Triple::OSType::AIX; break;
655         case ELFOSABI_FREEBSD:  ostype = llvm::Triple::OSType::FreeBSD; break;
656         case ELFOSABI_GNU:      ostype = llvm::Triple::OSType::Linux; break;
657         case ELFOSABI_NETBSD:   ostype = llvm::Triple::OSType::NetBSD; break;
658         case ELFOSABI_OPENBSD:  ostype = llvm::Triple::OSType::OpenBSD; break;
659         case ELFOSABI_SOLARIS:  ostype = llvm::Triple::OSType::Solaris; break;
660         default:
661             ostype = llvm::Triple::OSType::UnknownOS;
662     }
663     return ostype != llvm::Triple::OSType::UnknownOS;
664 }
665 
666 size_t
667 ObjectFileELF::GetModuleSpecifications (const lldb_private::FileSpec& file,
668                                         lldb::DataBufferSP& data_sp,
669                                         lldb::offset_t data_offset,
670                                         lldb::offset_t file_offset,
671                                         lldb::offset_t length,
672                                         lldb_private::ModuleSpecList &specs)
673 {
674     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_MODULES));
675 
676     const size_t initial_count = specs.GetSize();
677 
678     if (ObjectFileELF::MagicBytesMatch(data_sp, 0, data_sp->GetByteSize()))
679     {
680         DataExtractor data;
681         data.SetData(data_sp);
682         elf::ELFHeader header;
683         if (header.Parse(data, &data_offset))
684         {
685             if (data_sp)
686             {
687                 ModuleSpec spec (file);
688 
689                 const uint32_t sub_type = subTypeFromElfHeader(header);
690                 spec.GetArchitecture().SetArchitecture(eArchTypeELF,
691                                                        header.e_machine,
692                                                        sub_type,
693                                                        header.e_ident[EI_OSABI]);
694 
695                 if (spec.GetArchitecture().IsValid())
696                 {
697                     llvm::Triple::OSType ostype;
698                     llvm::Triple::VendorType vendor;
699                     llvm::Triple::OSType spec_ostype = spec.GetArchitecture ().GetTriple ().getOS ();
700 
701                     if (log)
702                         log->Printf ("ObjectFileELF::%s file '%s' module OSABI: %s", __FUNCTION__, file.GetPath ().c_str (), OSABIAsCString (header.e_ident[EI_OSABI]));
703 
704                     // SetArchitecture should have set the vendor to unknown
705                     vendor = spec.GetArchitecture ().GetTriple ().getVendor ();
706                     assert(vendor == llvm::Triple::UnknownVendor);
707 
708                     //
709                     // Validate it is ok to remove GetOsFromOSABI
710                     GetOsFromOSABI (header.e_ident[EI_OSABI], ostype);
711                     assert(spec_ostype == ostype);
712                     if (spec_ostype != llvm::Triple::OSType::UnknownOS)
713                     {
714                         if (log)
715                             log->Printf ("ObjectFileELF::%s file '%s' set ELF module OS type from ELF header OSABI.", __FUNCTION__, file.GetPath ().c_str ());
716                     }
717 
718                     // Try to get the UUID from the section list. Usually that's at the end, so
719                     // map the file in if we don't have it already.
720                     size_t section_header_end = header.e_shoff + header.e_shnum * header.e_shentsize;
721                     if (section_header_end > data_sp->GetByteSize())
722                     {
723                         data_sp = file.MemoryMapFileContentsIfLocal (file_offset, section_header_end);
724                         data.SetData(data_sp);
725                     }
726 
727                     uint32_t gnu_debuglink_crc = 0;
728                     std::string gnu_debuglink_file;
729                     SectionHeaderColl section_headers;
730                     lldb_private::UUID &uuid = spec.GetUUID();
731 
732                     GetSectionHeaderInfo(section_headers, data, header, uuid, gnu_debuglink_file, gnu_debuglink_crc, spec.GetArchitecture ());
733 
734                     llvm::Triple &spec_triple = spec.GetArchitecture ().GetTriple ();
735 
736                     if (log)
737                         log->Printf ("ObjectFileELF::%s file '%s' module set to triple: %s (architecture %s)", __FUNCTION__, file.GetPath ().c_str (), spec_triple.getTriple ().c_str (), spec.GetArchitecture ().GetArchitectureName ());
738 
739                     if (!uuid.IsValid())
740                     {
741                         uint32_t core_notes_crc = 0;
742 
743                         if (!gnu_debuglink_crc)
744                         {
745                             lldb_private::Timer scoped_timer (__PRETTY_FUNCTION__,
746                                                               "Calculating module crc32 %s with size %" PRIu64 " KiB",
747                                                               file.GetLastPathComponent().AsCString(),
748                                                               (file.GetByteSize()-file_offset)/1024);
749 
750                             // For core files - which usually don't happen to have a gnu_debuglink,
751                             // and are pretty bulky - calculating whole contents crc32 would be too much of luxury.
752                             // Thus we will need to fallback to something simpler.
753                             if (header.e_type == llvm::ELF::ET_CORE)
754                             {
755                                 size_t program_headers_end = header.e_phoff + header.e_phnum * header.e_phentsize;
756                                 if (program_headers_end > data_sp->GetByteSize())
757                                 {
758                                     data_sp = file.MemoryMapFileContentsIfLocal(file_offset, program_headers_end);
759                                     data.SetData(data_sp);
760                                 }
761                                 ProgramHeaderColl program_headers;
762                                 GetProgramHeaderInfo(program_headers, data, header);
763 
764                                 size_t segment_data_end = 0;
765                                 for (ProgramHeaderCollConstIter I = program_headers.begin();
766                                      I != program_headers.end(); ++I)
767                                 {
768                                      segment_data_end = std::max<unsigned long long> (I->p_offset + I->p_filesz, segment_data_end);
769                                 }
770 
771                                 if (segment_data_end > data_sp->GetByteSize())
772                                 {
773                                     data_sp = file.MemoryMapFileContentsIfLocal(file_offset, segment_data_end);
774                                     data.SetData(data_sp);
775                                 }
776 
777                                 core_notes_crc = CalculateELFNotesSegmentsCRC32 (program_headers, data);
778                             }
779                             else
780                             {
781                                 // Need to map entire file into memory to calculate the crc.
782                                 data_sp = file.MemoryMapFileContentsIfLocal (file_offset, SIZE_MAX);
783                                 data.SetData(data_sp);
784                                 gnu_debuglink_crc = calc_gnu_debuglink_crc32 (data.GetDataStart(), data.GetByteSize());
785                             }
786                         }
787                         if (gnu_debuglink_crc)
788                         {
789                             // Use 4 bytes of crc from the .gnu_debuglink section.
790                             uint32_t uuidt[4] = { gnu_debuglink_crc, 0, 0, 0 };
791                             uuid.SetBytes (uuidt, sizeof(uuidt));
792                         }
793                         else if (core_notes_crc)
794                         {
795                             // Use 8 bytes - first 4 bytes for *magic* prefix, mainly to make it look different form
796                             // .gnu_debuglink crc followed by 4 bytes of note segments crc.
797                             uint32_t uuidt[4] = { g_core_uuid_magic, core_notes_crc, 0, 0 };
798                             uuid.SetBytes (uuidt, sizeof(uuidt));
799                         }
800                     }
801 
802                     specs.Append(spec);
803                 }
804             }
805         }
806     }
807 
808     return specs.GetSize() - initial_count;
809 }
810 
811 //------------------------------------------------------------------
812 // PluginInterface protocol
813 //------------------------------------------------------------------
814 lldb_private::ConstString
815 ObjectFileELF::GetPluginName()
816 {
817     return GetPluginNameStatic();
818 }
819 
820 uint32_t
821 ObjectFileELF::GetPluginVersion()
822 {
823     return m_plugin_version;
824 }
825 //------------------------------------------------------------------
826 // ObjectFile protocol
827 //------------------------------------------------------------------
828 
829 ObjectFileELF::ObjectFileELF (const lldb::ModuleSP &module_sp,
830                               DataBufferSP& data_sp,
831                               lldb::offset_t data_offset,
832                               const FileSpec* file,
833                               lldb::offset_t file_offset,
834                               lldb::offset_t length) :
835     ObjectFile(module_sp, file, file_offset, length, data_sp, data_offset),
836     m_header(),
837     m_uuid(),
838     m_gnu_debuglink_file(),
839     m_gnu_debuglink_crc(0),
840     m_program_headers(),
841     m_section_headers(),
842     m_dynamic_symbols(),
843     m_filespec_ap(),
844     m_entry_point_address(),
845     m_arch_spec()
846 {
847     if (file)
848         m_file = *file;
849     ::memset(&m_header, 0, sizeof(m_header));
850 }
851 
852 ObjectFileELF::ObjectFileELF (const lldb::ModuleSP &module_sp,
853                               DataBufferSP& header_data_sp,
854                               const lldb::ProcessSP &process_sp,
855                               addr_t header_addr) :
856     ObjectFile(module_sp, process_sp, header_addr, header_data_sp),
857     m_header(),
858     m_uuid(),
859     m_gnu_debuglink_file(),
860     m_gnu_debuglink_crc(0),
861     m_program_headers(),
862     m_section_headers(),
863     m_dynamic_symbols(),
864     m_filespec_ap(),
865     m_entry_point_address(),
866     m_arch_spec()
867 {
868     ::memset(&m_header, 0, sizeof(m_header));
869 }
870 
871 ObjectFileELF::~ObjectFileELF()
872 {
873 }
874 
875 bool
876 ObjectFileELF::IsExecutable() const
877 {
878     return ((m_header.e_type & ET_EXEC) != 0) || (m_header.e_entry != 0);
879 }
880 
881 bool
882 ObjectFileELF::SetLoadAddress (Target &target,
883                                lldb::addr_t value,
884                                bool value_is_offset)
885 {
886     ModuleSP module_sp = GetModule();
887     if (module_sp)
888     {
889         size_t num_loaded_sections = 0;
890         SectionList *section_list = GetSectionList ();
891         if (section_list)
892         {
893             if (!value_is_offset)
894             {
895                 bool found_offset = false;
896                 for (size_t i = 0, count = GetProgramHeaderCount(); i < count; ++i)
897                 {
898                     const elf::ELFProgramHeader* header = GetProgramHeaderByIndex(i);
899                     if (header == nullptr)
900                         continue;
901 
902                     if (header->p_type != PT_LOAD || header->p_offset != 0)
903                         continue;
904 
905                     value = value - header->p_vaddr;
906                     found_offset = true;
907                     break;
908                 }
909                 if (!found_offset)
910                     return false;
911             }
912 
913             const size_t num_sections = section_list->GetSize();
914             size_t sect_idx = 0;
915 
916             for (sect_idx = 0; sect_idx < num_sections; ++sect_idx)
917             {
918                 // Iterate through the object file sections to find all
919                 // of the sections that have SHF_ALLOC in their flag bits.
920                 SectionSP section_sp (section_list->GetSectionAtIndex (sect_idx));
921                 // if (section_sp && !section_sp->IsThreadSpecific())
922                 if (section_sp && section_sp->Test(SHF_ALLOC))
923                 {
924                     lldb::addr_t load_addr = section_sp->GetFileAddress() + value;
925 
926                     // On 32-bit systems the load address have to fit into 4 bytes. The rest of
927                     // the bytes are the overflow from the addition.
928                     if (GetAddressByteSize() == 4)
929                         load_addr &= 0xFFFFFFFF;
930 
931                     if (target.GetSectionLoadList().SetSectionLoadAddress (section_sp, load_addr))
932                         ++num_loaded_sections;
933                 }
934             }
935             return num_loaded_sections > 0;
936         }
937     }
938     return false;
939 }
940 
941 ByteOrder
942 ObjectFileELF::GetByteOrder() const
943 {
944     if (m_header.e_ident[EI_DATA] == ELFDATA2MSB)
945         return eByteOrderBig;
946     if (m_header.e_ident[EI_DATA] == ELFDATA2LSB)
947         return eByteOrderLittle;
948     return eByteOrderInvalid;
949 }
950 
951 uint32_t
952 ObjectFileELF::GetAddressByteSize() const
953 {
954     return m_data.GetAddressByteSize();
955 }
956 
957 AddressClass
958 ObjectFileELF::GetAddressClass (addr_t file_addr)
959 {
960     Symtab* symtab = GetSymtab();
961     if (!symtab)
962         return eAddressClassUnknown;
963 
964     // The address class is determined based on the symtab. Ask it from the object file what
965     // contains the symtab information.
966     ObjectFile* symtab_objfile = symtab->GetObjectFile();
967     if (symtab_objfile != nullptr && symtab_objfile != this)
968         return symtab_objfile->GetAddressClass(file_addr);
969 
970     auto res = ObjectFile::GetAddressClass (file_addr);
971     if (res != eAddressClassCode)
972         return res;
973 
974     auto ub = m_address_class_map.upper_bound(file_addr);
975     if (ub == m_address_class_map.begin())
976     {
977         // No entry in the address class map before the address. Return
978         // default address class for an address in a code section.
979         return eAddressClassCode;
980     }
981 
982     // Move iterator to the address class entry preceding address
983     --ub;
984 
985     return ub->second;
986 }
987 
988 size_t
989 ObjectFileELF::SectionIndex(const SectionHeaderCollIter &I)
990 {
991     return std::distance(m_section_headers.begin(), I) + 1u;
992 }
993 
994 size_t
995 ObjectFileELF::SectionIndex(const SectionHeaderCollConstIter &I) const
996 {
997     return std::distance(m_section_headers.begin(), I) + 1u;
998 }
999 
1000 bool
1001 ObjectFileELF::ParseHeader()
1002 {
1003     lldb::offset_t offset = 0;
1004     if (!m_header.Parse(m_data, &offset))
1005         return false;
1006 
1007     if (!IsInMemory())
1008         return true;
1009 
1010     // For in memory object files m_data might not contain the full object file. Try to load it
1011     // until the end of the "Section header table" what is at the end of the ELF file.
1012     addr_t file_size = m_header.e_shoff + m_header.e_shnum * m_header.e_shentsize;
1013     if (m_data.GetByteSize() < file_size)
1014     {
1015         ProcessSP process_sp (m_process_wp.lock());
1016         if (!process_sp)
1017             return false;
1018 
1019         DataBufferSP data_sp = ReadMemory(process_sp, m_memory_addr, file_size);
1020         if (!data_sp)
1021             return false;
1022         m_data.SetData(data_sp, 0, file_size);
1023     }
1024 
1025     return true;
1026 }
1027 
1028 bool
1029 ObjectFileELF::GetUUID(lldb_private::UUID* uuid)
1030 {
1031     // Need to parse the section list to get the UUIDs, so make sure that's been done.
1032     if (!ParseSectionHeaders() && GetType() != ObjectFile::eTypeCoreFile)
1033         return false;
1034 
1035     if (m_uuid.IsValid())
1036     {
1037         // We have the full build id uuid.
1038         *uuid = m_uuid;
1039         return true;
1040     }
1041     else if (GetType() == ObjectFile::eTypeCoreFile)
1042     {
1043         uint32_t core_notes_crc = 0;
1044 
1045         if (!ParseProgramHeaders())
1046             return false;
1047 
1048         core_notes_crc = CalculateELFNotesSegmentsCRC32(m_program_headers, m_data);
1049 
1050         if (core_notes_crc)
1051         {
1052             // Use 8 bytes - first 4 bytes for *magic* prefix, mainly to make it
1053             // look different form .gnu_debuglink crc - followed by 4 bytes of note
1054             // segments crc.
1055             uint32_t uuidt[4] = { g_core_uuid_magic, core_notes_crc, 0, 0 };
1056             m_uuid.SetBytes (uuidt, sizeof(uuidt));
1057         }
1058     }
1059     else
1060     {
1061         if (!m_gnu_debuglink_crc)
1062             m_gnu_debuglink_crc = calc_gnu_debuglink_crc32 (m_data.GetDataStart(), m_data.GetByteSize());
1063         if (m_gnu_debuglink_crc)
1064         {
1065             // Use 4 bytes of crc from the .gnu_debuglink section.
1066             uint32_t uuidt[4] = { m_gnu_debuglink_crc, 0, 0, 0 };
1067             m_uuid.SetBytes (uuidt, sizeof(uuidt));
1068         }
1069     }
1070 
1071     if (m_uuid.IsValid())
1072     {
1073         *uuid = m_uuid;
1074         return true;
1075     }
1076 
1077     return false;
1078 }
1079 
1080 lldb_private::FileSpecList
1081 ObjectFileELF::GetDebugSymbolFilePaths()
1082 {
1083     FileSpecList file_spec_list;
1084 
1085     if (!m_gnu_debuglink_file.empty())
1086     {
1087         FileSpec file_spec (m_gnu_debuglink_file.c_str(), false);
1088         file_spec_list.Append (file_spec);
1089     }
1090     return file_spec_list;
1091 }
1092 
1093 uint32_t
1094 ObjectFileELF::GetDependentModules(FileSpecList &files)
1095 {
1096     size_t num_modules = ParseDependentModules();
1097     uint32_t num_specs = 0;
1098 
1099     for (unsigned i = 0; i < num_modules; ++i)
1100     {
1101         if (files.AppendIfUnique(m_filespec_ap->GetFileSpecAtIndex(i)))
1102             num_specs++;
1103     }
1104 
1105     return num_specs;
1106 }
1107 
1108 Address
1109 ObjectFileELF::GetImageInfoAddress(Target *target)
1110 {
1111     if (!ParseDynamicSymbols())
1112         return Address();
1113 
1114     SectionList *section_list = GetSectionList();
1115     if (!section_list)
1116         return Address();
1117 
1118     // Find the SHT_DYNAMIC (.dynamic) section.
1119     SectionSP dynsym_section_sp (section_list->FindSectionByType (eSectionTypeELFDynamicLinkInfo, true));
1120     if (!dynsym_section_sp)
1121         return Address();
1122     assert (dynsym_section_sp->GetObjectFile() == this);
1123 
1124     user_id_t dynsym_id = dynsym_section_sp->GetID();
1125     const ELFSectionHeaderInfo *dynsym_hdr = GetSectionHeaderByIndex(dynsym_id);
1126     if (!dynsym_hdr)
1127         return Address();
1128 
1129     for (size_t i = 0; i < m_dynamic_symbols.size(); ++i)
1130     {
1131         ELFDynamic &symbol = m_dynamic_symbols[i];
1132 
1133         if (symbol.d_tag == DT_DEBUG)
1134         {
1135             // Compute the offset as the number of previous entries plus the
1136             // size of d_tag.
1137             addr_t offset = i * dynsym_hdr->sh_entsize + GetAddressByteSize();
1138             return Address(dynsym_section_sp, offset);
1139         }
1140         // MIPS executables uses DT_MIPS_RLD_MAP_REL to support PIE. DT_MIPS_RLD_MAP exists in non-PIE.
1141         else if ((symbol.d_tag == DT_MIPS_RLD_MAP || symbol.d_tag == DT_MIPS_RLD_MAP_REL) && target)
1142         {
1143             addr_t offset = i * dynsym_hdr->sh_entsize + GetAddressByteSize();
1144             addr_t dyn_base = dynsym_section_sp->GetLoadBaseAddress(target);
1145             if (dyn_base == LLDB_INVALID_ADDRESS)
1146                 return Address();
1147 
1148             Error error;
1149             if (symbol.d_tag == DT_MIPS_RLD_MAP)
1150             {
1151                 // DT_MIPS_RLD_MAP tag stores an absolute address of the debug pointer.
1152                 Address addr;
1153                 if (target->ReadPointerFromMemory(dyn_base + offset, false, error, addr))
1154                     return addr;
1155             }
1156             if (symbol.d_tag == DT_MIPS_RLD_MAP_REL)
1157             {
1158                 // DT_MIPS_RLD_MAP_REL tag stores the offset to the debug pointer, relative to the address of the tag.
1159                 uint64_t rel_offset;
1160                 rel_offset = target->ReadUnsignedIntegerFromMemory(dyn_base + offset, false, GetAddressByteSize(), UINT64_MAX, error);
1161                 if (error.Success() && rel_offset != UINT64_MAX)
1162                 {
1163                     Address addr;
1164                     addr_t debug_ptr_address = dyn_base + (offset - GetAddressByteSize()) + rel_offset;
1165                     addr.SetOffset (debug_ptr_address);
1166                     return addr;
1167                 }
1168             }
1169         }
1170     }
1171 
1172     return Address();
1173 }
1174 
1175 lldb_private::Address
1176 ObjectFileELF::GetEntryPointAddress ()
1177 {
1178     if (m_entry_point_address.IsValid())
1179         return m_entry_point_address;
1180 
1181     if (!ParseHeader() || !IsExecutable())
1182         return m_entry_point_address;
1183 
1184     SectionList *section_list = GetSectionList();
1185     addr_t offset = m_header.e_entry;
1186 
1187     if (!section_list)
1188         m_entry_point_address.SetOffset(offset);
1189     else
1190         m_entry_point_address.ResolveAddressUsingFileSections(offset, section_list);
1191     return m_entry_point_address;
1192 }
1193 
1194 //----------------------------------------------------------------------
1195 // ParseDependentModules
1196 //----------------------------------------------------------------------
1197 size_t
1198 ObjectFileELF::ParseDependentModules()
1199 {
1200     if (m_filespec_ap.get())
1201         return m_filespec_ap->GetSize();
1202 
1203     m_filespec_ap.reset(new FileSpecList());
1204 
1205     if (!ParseSectionHeaders())
1206         return 0;
1207 
1208     SectionList *section_list = GetSectionList();
1209     if (!section_list)
1210         return 0;
1211 
1212     // Find the SHT_DYNAMIC section.
1213     Section *dynsym = section_list->FindSectionByType (eSectionTypeELFDynamicLinkInfo, true).get();
1214     if (!dynsym)
1215         return 0;
1216     assert (dynsym->GetObjectFile() == this);
1217 
1218     const ELFSectionHeaderInfo *header = GetSectionHeaderByIndex (dynsym->GetID());
1219     if (!header)
1220         return 0;
1221     // sh_link: section header index of string table used by entries in the section.
1222     Section *dynstr = section_list->FindSectionByID (header->sh_link + 1).get();
1223     if (!dynstr)
1224         return 0;
1225 
1226     DataExtractor dynsym_data;
1227     DataExtractor dynstr_data;
1228     if (ReadSectionData(dynsym, dynsym_data) &&
1229         ReadSectionData(dynstr, dynstr_data))
1230     {
1231         ELFDynamic symbol;
1232         const lldb::offset_t section_size = dynsym_data.GetByteSize();
1233         lldb::offset_t offset = 0;
1234 
1235         // The only type of entries we are concerned with are tagged DT_NEEDED,
1236         // yielding the name of a required library.
1237         while (offset < section_size)
1238         {
1239             if (!symbol.Parse(dynsym_data, &offset))
1240                 break;
1241 
1242             if (symbol.d_tag != DT_NEEDED)
1243                 continue;
1244 
1245             uint32_t str_index = static_cast<uint32_t>(symbol.d_val);
1246             const char *lib_name = dynstr_data.PeekCStr(str_index);
1247             m_filespec_ap->Append(FileSpec(lib_name, true));
1248         }
1249     }
1250 
1251     return m_filespec_ap->GetSize();
1252 }
1253 
1254 //----------------------------------------------------------------------
1255 // GetProgramHeaderInfo
1256 //----------------------------------------------------------------------
1257 size_t
1258 ObjectFileELF::GetProgramHeaderInfo(ProgramHeaderColl &program_headers,
1259                                     DataExtractor &object_data,
1260                                     const ELFHeader &header)
1261 {
1262     // We have already parsed the program headers
1263     if (!program_headers.empty())
1264         return program_headers.size();
1265 
1266     // If there are no program headers to read we are done.
1267     if (header.e_phnum == 0)
1268         return 0;
1269 
1270     program_headers.resize(header.e_phnum);
1271     if (program_headers.size() != header.e_phnum)
1272         return 0;
1273 
1274     const size_t ph_size = header.e_phnum * header.e_phentsize;
1275     const elf_off ph_offset = header.e_phoff;
1276     DataExtractor data;
1277     if (data.SetData(object_data, ph_offset, ph_size) != ph_size)
1278         return 0;
1279 
1280     uint32_t idx;
1281     lldb::offset_t offset;
1282     for (idx = 0, offset = 0; idx < header.e_phnum; ++idx)
1283     {
1284         if (program_headers[idx].Parse(data, &offset) == false)
1285             break;
1286     }
1287 
1288     if (idx < program_headers.size())
1289         program_headers.resize(idx);
1290 
1291     return program_headers.size();
1292 
1293 }
1294 
1295 //----------------------------------------------------------------------
1296 // ParseProgramHeaders
1297 //----------------------------------------------------------------------
1298 size_t
1299 ObjectFileELF::ParseProgramHeaders()
1300 {
1301     return GetProgramHeaderInfo(m_program_headers, m_data, m_header);
1302 }
1303 
1304 lldb_private::Error
1305 ObjectFileELF::RefineModuleDetailsFromNote (lldb_private::DataExtractor &data, lldb_private::ArchSpec &arch_spec, lldb_private::UUID &uuid)
1306 {
1307     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_MODULES));
1308     Error error;
1309 
1310     lldb::offset_t offset = 0;
1311 
1312     while (true)
1313     {
1314         // Parse the note header.  If this fails, bail out.
1315         const lldb::offset_t note_offset = offset;
1316         ELFNote note = ELFNote();
1317         if (!note.Parse(data, &offset))
1318         {
1319             // We're done.
1320             return error;
1321         }
1322 
1323         if (log)
1324             log->Printf ("ObjectFileELF::%s parsing note name='%s', type=%" PRIu32, __FUNCTION__, note.n_name.c_str (), note.n_type);
1325 
1326         // Process FreeBSD ELF notes.
1327         if ((note.n_name == LLDB_NT_OWNER_FREEBSD) &&
1328             (note.n_type == LLDB_NT_FREEBSD_ABI_TAG) &&
1329             (note.n_descsz == LLDB_NT_FREEBSD_ABI_SIZE))
1330         {
1331             // Pull out the min version info.
1332             uint32_t version_info;
1333             if (data.GetU32 (&offset, &version_info, 1) == nullptr)
1334             {
1335                 error.SetErrorString ("failed to read FreeBSD ABI note payload");
1336                 return error;
1337             }
1338 
1339             // Convert the version info into a major/minor number.
1340             const uint32_t version_major = version_info / 100000;
1341             const uint32_t version_minor = (version_info / 1000) % 100;
1342 
1343             char os_name[32];
1344             snprintf (os_name, sizeof (os_name), "freebsd%" PRIu32 ".%" PRIu32, version_major, version_minor);
1345 
1346             // Set the elf OS version to FreeBSD.  Also clear the vendor.
1347             arch_spec.GetTriple ().setOSName (os_name);
1348             arch_spec.GetTriple ().setVendor (llvm::Triple::VendorType::UnknownVendor);
1349 
1350             if (log)
1351                 log->Printf ("ObjectFileELF::%s detected FreeBSD %" PRIu32 ".%" PRIu32 ".%" PRIu32, __FUNCTION__, version_major, version_minor, static_cast<uint32_t> (version_info % 1000));
1352         }
1353         // Process GNU ELF notes.
1354         else if (note.n_name == LLDB_NT_OWNER_GNU)
1355         {
1356             switch (note.n_type)
1357             {
1358                 case LLDB_NT_GNU_ABI_TAG:
1359                     if (note.n_descsz == LLDB_NT_GNU_ABI_SIZE)
1360                     {
1361                         // Pull out the min OS version supporting the ABI.
1362                         uint32_t version_info[4];
1363                         if (data.GetU32 (&offset, &version_info[0], note.n_descsz / 4) == nullptr)
1364                         {
1365                             error.SetErrorString ("failed to read GNU ABI note payload");
1366                             return error;
1367                         }
1368 
1369                         // Set the OS per the OS field.
1370                         switch (version_info[0])
1371                         {
1372                             case LLDB_NT_GNU_ABI_OS_LINUX:
1373                                 arch_spec.GetTriple ().setOS (llvm::Triple::OSType::Linux);
1374                                 arch_spec.GetTriple ().setVendor (llvm::Triple::VendorType::UnknownVendor);
1375                                 if (log)
1376                                     log->Printf ("ObjectFileELF::%s detected Linux, min version %" PRIu32 ".%" PRIu32 ".%" PRIu32, __FUNCTION__, version_info[1], version_info[2], version_info[3]);
1377                                 // FIXME we have the minimal version number, we could be propagating that.  version_info[1] = OS Major, version_info[2] = OS Minor, version_info[3] = Revision.
1378                                 break;
1379                             case LLDB_NT_GNU_ABI_OS_HURD:
1380                                 arch_spec.GetTriple ().setOS (llvm::Triple::OSType::UnknownOS);
1381                                 arch_spec.GetTriple ().setVendor (llvm::Triple::VendorType::UnknownVendor);
1382                                 if (log)
1383                                     log->Printf ("ObjectFileELF::%s detected Hurd (unsupported), min version %" PRIu32 ".%" PRIu32 ".%" PRIu32, __FUNCTION__, version_info[1], version_info[2], version_info[3]);
1384                                 break;
1385                             case LLDB_NT_GNU_ABI_OS_SOLARIS:
1386                                 arch_spec.GetTriple ().setOS (llvm::Triple::OSType::Solaris);
1387                                 arch_spec.GetTriple ().setVendor (llvm::Triple::VendorType::UnknownVendor);
1388                                 if (log)
1389                                     log->Printf ("ObjectFileELF::%s detected Solaris, min version %" PRIu32 ".%" PRIu32 ".%" PRIu32, __FUNCTION__, version_info[1], version_info[2], version_info[3]);
1390                                 break;
1391                             default:
1392                                 if (log)
1393                                     log->Printf ("ObjectFileELF::%s unrecognized OS in note, id %" PRIu32 ", min version %" PRIu32 ".%" PRIu32 ".%" PRIu32, __FUNCTION__, version_info[0], version_info[1], version_info[2], version_info[3]);
1394                                 break;
1395                         }
1396                     }
1397                     break;
1398 
1399                 case LLDB_NT_GNU_BUILD_ID_TAG:
1400                     // Only bother processing this if we don't already have the uuid set.
1401                     if (!uuid.IsValid())
1402                     {
1403                         // 16 bytes is UUID|MD5, 20 bytes is SHA1
1404                         if ((note.n_descsz == 16 || note.n_descsz == 20))
1405                         {
1406                             uint8_t uuidbuf[20];
1407                             if (data.GetU8 (&offset, &uuidbuf, note.n_descsz) == nullptr)
1408                             {
1409                                 error.SetErrorString ("failed to read GNU_BUILD_ID note payload");
1410                                 return error;
1411                             }
1412 
1413                             // Save the build id as the UUID for the module.
1414                             uuid.SetBytes (uuidbuf, note.n_descsz);
1415                         }
1416                     }
1417                     break;
1418             }
1419         }
1420         // Process NetBSD ELF notes.
1421         else if ((note.n_name == LLDB_NT_OWNER_NETBSD) &&
1422                  (note.n_type == LLDB_NT_NETBSD_ABI_TAG) &&
1423                  (note.n_descsz == LLDB_NT_NETBSD_ABI_SIZE))
1424         {
1425             // Pull out the min version info.
1426             uint32_t version_info;
1427             if (data.GetU32 (&offset, &version_info, 1) == nullptr)
1428             {
1429                 error.SetErrorString ("failed to read NetBSD ABI note payload");
1430                 return error;
1431             }
1432 
1433             // Set the elf OS version to NetBSD.  Also clear the vendor.
1434             arch_spec.GetTriple ().setOS (llvm::Triple::OSType::NetBSD);
1435             arch_spec.GetTriple ().setVendor (llvm::Triple::VendorType::UnknownVendor);
1436 
1437             if (log)
1438                 log->Printf ("ObjectFileELF::%s detected NetBSD, min version constant %" PRIu32, __FUNCTION__, version_info);
1439         }
1440         // Process CSR kalimba notes
1441         else if ((note.n_type == LLDB_NT_GNU_ABI_TAG) &&
1442                 (note.n_name == LLDB_NT_OWNER_CSR))
1443         {
1444             arch_spec.GetTriple().setOS(llvm::Triple::OSType::UnknownOS);
1445             arch_spec.GetTriple().setVendor(llvm::Triple::VendorType::CSR);
1446 
1447             // TODO At some point the description string could be processed.
1448             // It could provide a steer towards the kalimba variant which
1449             // this ELF targets.
1450             if(note.n_descsz)
1451             {
1452                 const char *cstr = data.GetCStr(&offset, llvm::alignTo (note.n_descsz, 4));
1453                 (void)cstr;
1454             }
1455         }
1456         else if (note.n_name == LLDB_NT_OWNER_ANDROID)
1457         {
1458             arch_spec.GetTriple().setOS(llvm::Triple::OSType::Linux);
1459             arch_spec.GetTriple().setEnvironment(llvm::Triple::EnvironmentType::Android);
1460         }
1461         else if (note.n_name == LLDB_NT_OWNER_LINUX)
1462         {
1463             // This is sometimes found in core files and usually contains extended register info
1464             arch_spec.GetTriple().setOS(llvm::Triple::OSType::Linux);
1465         }
1466         else if (note.n_name == LLDB_NT_OWNER_CORE)
1467         {
1468             // Parse the NT_FILE to look for stuff in paths to shared libraries
1469             // As the contents look like:
1470             // count     = 0x000000000000000a (10)
1471             // page_size = 0x0000000000001000 (4096)
1472             // Index start              end                file_ofs           path
1473             // ===== ------------------ ------------------ ------------------ -------------------------------------
1474             // [  0] 0x0000000000400000 0x0000000000401000 0x0000000000000000 /tmp/a.out
1475             // [  1] 0x0000000000600000 0x0000000000601000 0x0000000000000000 /tmp/a.out
1476             // [  2] 0x0000000000601000 0x0000000000602000 0x0000000000000001 /tmp/a.out
1477             // [  3] 0x00007fa79c9ed000 0x00007fa79cba8000 0x0000000000000000 /lib/x86_64-linux-gnu/libc-2.19.so
1478             // [  4] 0x00007fa79cba8000 0x00007fa79cda7000 0x00000000000001bb /lib/x86_64-linux-gnu/libc-2.19.so
1479             // [  5] 0x00007fa79cda7000 0x00007fa79cdab000 0x00000000000001ba /lib/x86_64-linux-gnu/libc-2.19.so
1480             // [  6] 0x00007fa79cdab000 0x00007fa79cdad000 0x00000000000001be /lib/x86_64-linux-gnu/libc-2.19.so
1481             // [  7] 0x00007fa79cdb2000 0x00007fa79cdd5000 0x0000000000000000 /lib/x86_64-linux-gnu/ld-2.19.so
1482             // [  8] 0x00007fa79cfd4000 0x00007fa79cfd5000 0x0000000000000022 /lib/x86_64-linux-gnu/ld-2.19.so
1483             // [  9] 0x00007fa79cfd5000 0x00007fa79cfd6000 0x0000000000000023 /lib/x86_64-linux-gnu/ld-2.19.so
1484             if (note.n_type == NT_FILE)
1485             {
1486                 uint64_t count = data.GetU64(&offset);
1487                 offset += 8 + 3*8*count; // Skip page size and all start/end/file_ofs
1488                 for (size_t i=0; i<count; ++i)
1489                 {
1490                     llvm::StringRef path(data.GetCStr(&offset));
1491                     if (path.startswith("/lib/x86_64-linux-gnu"))
1492                     {
1493                         arch_spec.GetTriple().setOS(llvm::Triple::OSType::Linux);
1494                         break;
1495                     }
1496                 }
1497             }
1498         }
1499 
1500         // Calculate the offset of the next note just in case "offset" has been used
1501         // to poke at the contents of the note data
1502         offset = note_offset + note.GetByteSize();
1503     }
1504 
1505     return error;
1506 }
1507 
1508 
1509 //----------------------------------------------------------------------
1510 // GetSectionHeaderInfo
1511 //----------------------------------------------------------------------
1512 size_t
1513 ObjectFileELF::GetSectionHeaderInfo(SectionHeaderColl &section_headers,
1514                                     lldb_private::DataExtractor &object_data,
1515                                     const elf::ELFHeader &header,
1516                                     lldb_private::UUID &uuid,
1517                                     std::string &gnu_debuglink_file,
1518                                     uint32_t &gnu_debuglink_crc,
1519                                     ArchSpec &arch_spec)
1520 {
1521     // Don't reparse the section headers if we already did that.
1522     if (!section_headers.empty())
1523         return section_headers.size();
1524 
1525     // Only initialize the arch_spec to okay defaults if they're not already set.
1526     // We'll refine this with note data as we parse the notes.
1527     if (arch_spec.GetTriple ().getOS () == llvm::Triple::OSType::UnknownOS)
1528     {
1529         llvm::Triple::OSType ostype;
1530         llvm::Triple::OSType spec_ostype;
1531         const uint32_t sub_type = subTypeFromElfHeader(header);
1532         arch_spec.SetArchitecture (eArchTypeELF, header.e_machine, sub_type, header.e_ident[EI_OSABI]);
1533         //
1534         // Validate if it is ok to remove GetOsFromOSABI
1535         GetOsFromOSABI (header.e_ident[EI_OSABI], ostype);
1536         spec_ostype = arch_spec.GetTriple ().getOS ();
1537         assert(spec_ostype == ostype);
1538     }
1539 
1540     if (arch_spec.GetMachine() == llvm::Triple::mips || arch_spec.GetMachine() == llvm::Triple::mipsel
1541         || arch_spec.GetMachine() == llvm::Triple::mips64 || arch_spec.GetMachine() == llvm::Triple::mips64el)
1542     {
1543         switch (header.e_flags & llvm::ELF::EF_MIPS_ARCH_ASE)
1544         {
1545             case llvm::ELF::EF_MIPS_MICROMIPS:
1546                 arch_spec.SetFlags (ArchSpec::eMIPSAse_micromips);
1547                 break;
1548             case llvm::ELF::EF_MIPS_ARCH_ASE_M16:
1549                 arch_spec.SetFlags (ArchSpec::eMIPSAse_mips16);
1550                 break;
1551             case llvm::ELF::EF_MIPS_ARCH_ASE_MDMX:
1552                 arch_spec.SetFlags (ArchSpec::eMIPSAse_mdmx);
1553                 break;
1554             default:
1555                 break;
1556         }
1557     }
1558 
1559     // If there are no section headers we are done.
1560     if (header.e_shnum == 0)
1561         return 0;
1562 
1563     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_MODULES));
1564 
1565     section_headers.resize(header.e_shnum);
1566     if (section_headers.size() != header.e_shnum)
1567         return 0;
1568 
1569     const size_t sh_size = header.e_shnum * header.e_shentsize;
1570     const elf_off sh_offset = header.e_shoff;
1571     DataExtractor sh_data;
1572     if (sh_data.SetData (object_data, sh_offset, sh_size) != sh_size)
1573         return 0;
1574 
1575     uint32_t idx;
1576     lldb::offset_t offset;
1577     for (idx = 0, offset = 0; idx < header.e_shnum; ++idx)
1578     {
1579         if (section_headers[idx].Parse(sh_data, &offset) == false)
1580             break;
1581     }
1582     if (idx < section_headers.size())
1583         section_headers.resize(idx);
1584 
1585     const unsigned strtab_idx = header.e_shstrndx;
1586     if (strtab_idx && strtab_idx < section_headers.size())
1587     {
1588         const ELFSectionHeaderInfo &sheader = section_headers[strtab_idx];
1589         const size_t byte_size = sheader.sh_size;
1590         const Elf64_Off offset = sheader.sh_offset;
1591         lldb_private::DataExtractor shstr_data;
1592 
1593         if (shstr_data.SetData (object_data, offset, byte_size) == byte_size)
1594         {
1595             for (SectionHeaderCollIter I = section_headers.begin();
1596                  I != section_headers.end(); ++I)
1597             {
1598                 static ConstString g_sect_name_gnu_debuglink (".gnu_debuglink");
1599                 const ELFSectionHeaderInfo &sheader = *I;
1600                 const uint64_t section_size = sheader.sh_type == SHT_NOBITS ? 0 : sheader.sh_size;
1601                 ConstString name(shstr_data.PeekCStr(I->sh_name));
1602 
1603                 I->section_name = name;
1604 
1605                 if (arch_spec.GetMachine() == llvm::Triple::mips || arch_spec.GetMachine() == llvm::Triple::mipsel
1606                     || arch_spec.GetMachine() == llvm::Triple::mips64 || arch_spec.GetMachine() == llvm::Triple::mips64el)
1607                 {
1608                     uint32_t arch_flags = arch_spec.GetFlags ();
1609                     DataExtractor data;
1610                     if (sheader.sh_type == SHT_MIPS_ABIFLAGS)
1611                     {
1612 
1613                         if (section_size && (data.SetData (object_data, sheader.sh_offset, section_size) == section_size))
1614                         {
1615                             lldb::offset_t ase_offset = 12; // MIPS ABI Flags Version: 0
1616                             arch_flags |= data.GetU32 (&ase_offset);
1617                         }
1618                     }
1619                     // Settings appropriate ArchSpec ABI Flags
1620                     if (header.e_flags & llvm::ELF::EF_MIPS_ABI2)
1621                     {
1622                         arch_flags |= lldb_private::ArchSpec::eMIPSABI_N32;
1623                     }
1624                     else if (header.e_flags & llvm::ELF::EF_MIPS_ABI_O32)
1625                     {
1626                          arch_flags |= lldb_private::ArchSpec::eMIPSABI_O32;
1627                     }
1628                     arch_spec.SetFlags (arch_flags);
1629                 }
1630 
1631                 if (name == g_sect_name_gnu_debuglink)
1632                 {
1633                     DataExtractor data;
1634                     if (section_size && (data.SetData (object_data, sheader.sh_offset, section_size) == section_size))
1635                     {
1636                         lldb::offset_t gnu_debuglink_offset = 0;
1637                         gnu_debuglink_file = data.GetCStr (&gnu_debuglink_offset);
1638                         gnu_debuglink_offset = llvm::alignTo (gnu_debuglink_offset, 4);
1639                         data.GetU32 (&gnu_debuglink_offset, &gnu_debuglink_crc, 1);
1640                     }
1641                 }
1642 
1643                 // Process ELF note section entries.
1644                 bool is_note_header = (sheader.sh_type == SHT_NOTE);
1645 
1646                 // The section header ".note.android.ident" is stored as a
1647                 // PROGBITS type header but it is actually a note header.
1648                 static ConstString g_sect_name_android_ident (".note.android.ident");
1649                 if (!is_note_header && name == g_sect_name_android_ident)
1650                     is_note_header = true;
1651 
1652                 if (is_note_header)
1653                 {
1654                     // Allow notes to refine module info.
1655                     DataExtractor data;
1656                     if (section_size && (data.SetData (object_data, sheader.sh_offset, section_size) == section_size))
1657                     {
1658                         Error error = RefineModuleDetailsFromNote (data, arch_spec, uuid);
1659                         if (error.Fail ())
1660                         {
1661                             if (log)
1662                                 log->Printf ("ObjectFileELF::%s ELF note processing failed: %s", __FUNCTION__, error.AsCString ());
1663                         }
1664                     }
1665                 }
1666             }
1667 
1668             // Make any unknown triple components to be unspecified unknowns.
1669             if (arch_spec.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
1670                 arch_spec.GetTriple().setVendorName (llvm::StringRef());
1671             if (arch_spec.GetTriple().getOS() == llvm::Triple::UnknownOS)
1672                 arch_spec.GetTriple().setOSName (llvm::StringRef());
1673 
1674             return section_headers.size();
1675         }
1676     }
1677 
1678     section_headers.clear();
1679     return 0;
1680 }
1681 
1682 size_t
1683 ObjectFileELF::GetProgramHeaderCount()
1684 {
1685     return ParseProgramHeaders();
1686 }
1687 
1688 const elf::ELFProgramHeader *
1689 ObjectFileELF::GetProgramHeaderByIndex(lldb::user_id_t id)
1690 {
1691     if (!id || !ParseProgramHeaders())
1692         return NULL;
1693 
1694     if (--id < m_program_headers.size())
1695         return &m_program_headers[id];
1696 
1697     return NULL;
1698 }
1699 
1700 DataExtractor
1701 ObjectFileELF::GetSegmentDataByIndex(lldb::user_id_t id)
1702 {
1703     const elf::ELFProgramHeader *segment_header = GetProgramHeaderByIndex(id);
1704     if (segment_header == NULL)
1705         return DataExtractor();
1706     return DataExtractor(m_data, segment_header->p_offset, segment_header->p_filesz);
1707 }
1708 
1709 std::string
1710 ObjectFileELF::StripLinkerSymbolAnnotations(llvm::StringRef symbol_name) const
1711 {
1712     size_t pos = symbol_name.find('@');
1713     return symbol_name.substr(0, pos).str();
1714 }
1715 
1716 //----------------------------------------------------------------------
1717 // ParseSectionHeaders
1718 //----------------------------------------------------------------------
1719 size_t
1720 ObjectFileELF::ParseSectionHeaders()
1721 {
1722     return GetSectionHeaderInfo(m_section_headers, m_data, m_header, m_uuid, m_gnu_debuglink_file, m_gnu_debuglink_crc, m_arch_spec);
1723 }
1724 
1725 const ObjectFileELF::ELFSectionHeaderInfo *
1726 ObjectFileELF::GetSectionHeaderByIndex(lldb::user_id_t id)
1727 {
1728     if (!id || !ParseSectionHeaders())
1729         return NULL;
1730 
1731     if (--id < m_section_headers.size())
1732         return &m_section_headers[id];
1733 
1734     return NULL;
1735 }
1736 
1737 lldb::user_id_t
1738 ObjectFileELF::GetSectionIndexByName(const char* name)
1739 {
1740     if (!name || !name[0] || !ParseSectionHeaders())
1741         return 0;
1742     for (size_t i = 1; i < m_section_headers.size(); ++i)
1743         if (m_section_headers[i].section_name == ConstString(name))
1744             return i;
1745     return 0;
1746 }
1747 
1748 void
1749 ObjectFileELF::CreateSections(SectionList &unified_section_list)
1750 {
1751     if (!m_sections_ap.get() && ParseSectionHeaders())
1752     {
1753         m_sections_ap.reset(new SectionList());
1754 
1755         for (SectionHeaderCollIter I = m_section_headers.begin();
1756              I != m_section_headers.end(); ++I)
1757         {
1758             const ELFSectionHeaderInfo &header = *I;
1759 
1760             ConstString& name = I->section_name;
1761             const uint64_t file_size = header.sh_type == SHT_NOBITS ? 0 : header.sh_size;
1762             const uint64_t vm_size = header.sh_flags & SHF_ALLOC ? header.sh_size : 0;
1763 
1764             static ConstString g_sect_name_text (".text");
1765             static ConstString g_sect_name_data (".data");
1766             static ConstString g_sect_name_bss (".bss");
1767             static ConstString g_sect_name_tdata (".tdata");
1768             static ConstString g_sect_name_tbss (".tbss");
1769             static ConstString g_sect_name_dwarf_debug_abbrev (".debug_abbrev");
1770             static ConstString g_sect_name_dwarf_debug_addr (".debug_addr");
1771             static ConstString g_sect_name_dwarf_debug_aranges (".debug_aranges");
1772             static ConstString g_sect_name_dwarf_debug_frame (".debug_frame");
1773             static ConstString g_sect_name_dwarf_debug_info (".debug_info");
1774             static ConstString g_sect_name_dwarf_debug_line (".debug_line");
1775             static ConstString g_sect_name_dwarf_debug_loc (".debug_loc");
1776             static ConstString g_sect_name_dwarf_debug_macinfo (".debug_macinfo");
1777             static ConstString g_sect_name_dwarf_debug_macro (".debug_macro");
1778             static ConstString g_sect_name_dwarf_debug_pubnames (".debug_pubnames");
1779             static ConstString g_sect_name_dwarf_debug_pubtypes (".debug_pubtypes");
1780             static ConstString g_sect_name_dwarf_debug_ranges (".debug_ranges");
1781             static ConstString g_sect_name_dwarf_debug_str (".debug_str");
1782             static ConstString g_sect_name_dwarf_debug_str_offsets (".debug_str_offsets");
1783             static ConstString g_sect_name_dwarf_debug_abbrev_dwo (".debug_abbrev.dwo");
1784             static ConstString g_sect_name_dwarf_debug_info_dwo (".debug_info.dwo");
1785             static ConstString g_sect_name_dwarf_debug_line_dwo (".debug_line.dwo");
1786             static ConstString g_sect_name_dwarf_debug_macro_dwo (".debug_macro.dwo");
1787             static ConstString g_sect_name_dwarf_debug_loc_dwo (".debug_loc.dwo");
1788             static ConstString g_sect_name_dwarf_debug_str_dwo (".debug_str.dwo");
1789             static ConstString g_sect_name_dwarf_debug_str_offsets_dwo (".debug_str_offsets.dwo");
1790             static ConstString g_sect_name_eh_frame (".eh_frame");
1791             static ConstString g_sect_name_arm_exidx (".ARM.exidx");
1792             static ConstString g_sect_name_arm_extab (".ARM.extab");
1793             static ConstString g_sect_name_go_symtab (".gosymtab");
1794 
1795             SectionType sect_type = eSectionTypeOther;
1796 
1797             bool is_thread_specific = false;
1798 
1799             if      (name == g_sect_name_text)                  sect_type = eSectionTypeCode;
1800             else if (name == g_sect_name_data)                  sect_type = eSectionTypeData;
1801             else if (name == g_sect_name_bss)                   sect_type = eSectionTypeZeroFill;
1802             else if (name == g_sect_name_tdata)
1803             {
1804                 sect_type = eSectionTypeData;
1805                 is_thread_specific = true;
1806             }
1807             else if (name == g_sect_name_tbss)
1808             {
1809                 sect_type = eSectionTypeZeroFill;
1810                 is_thread_specific = true;
1811             }
1812             // .debug_abbrev – Abbreviations used in the .debug_info section
1813             // .debug_aranges – Lookup table for mapping addresses to compilation units
1814             // .debug_frame – Call frame information
1815             // .debug_info – The core DWARF information section
1816             // .debug_line – Line number information
1817             // .debug_loc – Location lists used in DW_AT_location attributes
1818             // .debug_macinfo – Macro information
1819             // .debug_pubnames – Lookup table for mapping object and function names to compilation units
1820             // .debug_pubtypes – Lookup table for mapping type names to compilation units
1821             // .debug_ranges – Address ranges used in DW_AT_ranges attributes
1822             // .debug_str – String table used in .debug_info
1823             // MISSING? .gnu_debugdata - "mini debuginfo / MiniDebugInfo" section, http://sourceware.org/gdb/onlinedocs/gdb/MiniDebugInfo.html
1824             // MISSING? .debug-index - http://src.chromium.org/viewvc/chrome/trunk/src/build/gdb-add-index?pathrev=144644
1825             // MISSING? .debug_types - Type descriptions from DWARF 4? See http://gcc.gnu.org/wiki/DwarfSeparateTypeInfo
1826             else if (name == g_sect_name_dwarf_debug_abbrev)          sect_type = eSectionTypeDWARFDebugAbbrev;
1827             else if (name == g_sect_name_dwarf_debug_addr)            sect_type = eSectionTypeDWARFDebugAddr;
1828             else if (name == g_sect_name_dwarf_debug_aranges)         sect_type = eSectionTypeDWARFDebugAranges;
1829             else if (name == g_sect_name_dwarf_debug_frame)           sect_type = eSectionTypeDWARFDebugFrame;
1830             else if (name == g_sect_name_dwarf_debug_info)            sect_type = eSectionTypeDWARFDebugInfo;
1831             else if (name == g_sect_name_dwarf_debug_line)            sect_type = eSectionTypeDWARFDebugLine;
1832             else if (name == g_sect_name_dwarf_debug_loc)             sect_type = eSectionTypeDWARFDebugLoc;
1833             else if (name == g_sect_name_dwarf_debug_macinfo)         sect_type = eSectionTypeDWARFDebugMacInfo;
1834             else if (name == g_sect_name_dwarf_debug_macro)           sect_type = eSectionTypeDWARFDebugMacro;
1835             else if (name == g_sect_name_dwarf_debug_pubnames)        sect_type = eSectionTypeDWARFDebugPubNames;
1836             else if (name == g_sect_name_dwarf_debug_pubtypes)        sect_type = eSectionTypeDWARFDebugPubTypes;
1837             else if (name == g_sect_name_dwarf_debug_ranges)          sect_type = eSectionTypeDWARFDebugRanges;
1838             else if (name == g_sect_name_dwarf_debug_str)             sect_type = eSectionTypeDWARFDebugStr;
1839             else if (name == g_sect_name_dwarf_debug_str_offsets)     sect_type = eSectionTypeDWARFDebugStrOffsets;
1840             else if (name == g_sect_name_dwarf_debug_abbrev_dwo)      sect_type = eSectionTypeDWARFDebugAbbrev;
1841             else if (name == g_sect_name_dwarf_debug_info_dwo)        sect_type = eSectionTypeDWARFDebugInfo;
1842             else if (name == g_sect_name_dwarf_debug_line_dwo)        sect_type = eSectionTypeDWARFDebugLine;
1843             else if (name == g_sect_name_dwarf_debug_macro_dwo)       sect_type = eSectionTypeDWARFDebugMacro;
1844             else if (name == g_sect_name_dwarf_debug_loc_dwo)         sect_type = eSectionTypeDWARFDebugLoc;
1845             else if (name == g_sect_name_dwarf_debug_str_dwo)         sect_type = eSectionTypeDWARFDebugStr;
1846             else if (name == g_sect_name_dwarf_debug_str_offsets_dwo) sect_type = eSectionTypeDWARFDebugStrOffsets;
1847             else if (name == g_sect_name_eh_frame)                    sect_type = eSectionTypeEHFrame;
1848             else if (name == g_sect_name_arm_exidx)                   sect_type = eSectionTypeARMexidx;
1849             else if (name == g_sect_name_arm_extab)                   sect_type = eSectionTypeARMextab;
1850             else if (name == g_sect_name_go_symtab)                   sect_type = eSectionTypeGoSymtab;
1851 
1852             switch (header.sh_type)
1853             {
1854                 case SHT_SYMTAB:
1855                     assert (sect_type == eSectionTypeOther);
1856                     sect_type = eSectionTypeELFSymbolTable;
1857                     break;
1858                 case SHT_DYNSYM:
1859                     assert (sect_type == eSectionTypeOther);
1860                     sect_type = eSectionTypeELFDynamicSymbols;
1861                     break;
1862                 case SHT_RELA:
1863                 case SHT_REL:
1864                     assert (sect_type == eSectionTypeOther);
1865                     sect_type = eSectionTypeELFRelocationEntries;
1866                     break;
1867                 case SHT_DYNAMIC:
1868                     assert (sect_type == eSectionTypeOther);
1869                     sect_type = eSectionTypeELFDynamicLinkInfo;
1870                     break;
1871             }
1872 
1873             if (eSectionTypeOther == sect_type)
1874             {
1875                 // the kalimba toolchain assumes that ELF section names are free-form. It does
1876                 // support linkscripts which (can) give rise to various arbitrarily named
1877                 // sections being "Code" or "Data".
1878                 sect_type = kalimbaSectionType(m_header, header);
1879             }
1880 
1881             const uint32_t target_bytes_size =
1882                 (eSectionTypeData == sect_type || eSectionTypeZeroFill == sect_type) ?
1883                 m_arch_spec.GetDataByteSize() :
1884                     eSectionTypeCode == sect_type ?
1885                     m_arch_spec.GetCodeByteSize() : 1;
1886 
1887             elf::elf_xword log2align = (header.sh_addralign==0)
1888                                         ? 0
1889                                         : llvm::Log2_64(header.sh_addralign);
1890             SectionSP section_sp (new Section(GetModule(),        // Module to which this section belongs.
1891                                               this,               // ObjectFile to which this section belongs and should read section data from.
1892                                               SectionIndex(I),    // Section ID.
1893                                               name,               // Section name.
1894                                               sect_type,          // Section type.
1895                                               header.sh_addr,     // VM address.
1896                                               vm_size,            // VM size in bytes of this section.
1897                                               header.sh_offset,   // Offset of this section in the file.
1898                                               file_size,          // Size of the section as found in the file.
1899                                               log2align,          // Alignment of the section
1900                                               header.sh_flags,    // Flags for this section.
1901                                               target_bytes_size));// Number of host bytes per target byte
1902 
1903             if (is_thread_specific)
1904                 section_sp->SetIsThreadSpecific (is_thread_specific);
1905             m_sections_ap->AddSection(section_sp);
1906         }
1907     }
1908 
1909     if (m_sections_ap.get())
1910     {
1911         if (GetType() == eTypeDebugInfo)
1912         {
1913             static const SectionType g_sections[] =
1914             {
1915                 eSectionTypeDWARFDebugAbbrev,
1916                 eSectionTypeDWARFDebugAddr,
1917                 eSectionTypeDWARFDebugAranges,
1918                 eSectionTypeDWARFDebugFrame,
1919                 eSectionTypeDWARFDebugInfo,
1920                 eSectionTypeDWARFDebugLine,
1921                 eSectionTypeDWARFDebugLoc,
1922                 eSectionTypeDWARFDebugMacInfo,
1923                 eSectionTypeDWARFDebugPubNames,
1924                 eSectionTypeDWARFDebugPubTypes,
1925                 eSectionTypeDWARFDebugRanges,
1926                 eSectionTypeDWARFDebugStr,
1927                 eSectionTypeDWARFDebugStrOffsets,
1928                 eSectionTypeELFSymbolTable,
1929             };
1930             SectionList *elf_section_list = m_sections_ap.get();
1931             for (size_t idx = 0; idx < sizeof(g_sections) / sizeof(g_sections[0]); ++idx)
1932             {
1933                 SectionType section_type = g_sections[idx];
1934                 SectionSP section_sp (elf_section_list->FindSectionByType (section_type, true));
1935                 if (section_sp)
1936                 {
1937                     SectionSP module_section_sp (unified_section_list.FindSectionByType (section_type, true));
1938                     if (module_section_sp)
1939                         unified_section_list.ReplaceSection (module_section_sp->GetID(), section_sp);
1940                     else
1941                         unified_section_list.AddSection (section_sp);
1942                 }
1943             }
1944         }
1945         else
1946         {
1947             unified_section_list = *m_sections_ap;
1948         }
1949     }
1950 }
1951 
1952 // Find the arm/aarch64 mapping symbol character in the given symbol name. Mapping symbols have the
1953 // form of "$<char>[.<any>]*". Additionally we recognize cases when the mapping symbol prefixed by
1954 // an arbitrary string because if a symbol prefix added to each symbol in the object file with
1955 // objcopy then the mapping symbols are also prefixed.
1956 static char
1957 FindArmAarch64MappingSymbol(const char* symbol_name)
1958 {
1959     if (!symbol_name)
1960         return '\0';
1961 
1962     const char* dollar_pos = ::strchr(symbol_name, '$');
1963     if (!dollar_pos || dollar_pos[1] == '\0')
1964         return '\0';
1965 
1966     if (dollar_pos[2] == '\0' || dollar_pos[2] == '.')
1967         return dollar_pos[1];
1968     return '\0';
1969 }
1970 
1971 #define STO_MIPS_ISA            (3 << 6)
1972 #define STO_MICROMIPS           (2 << 6)
1973 #define IS_MICROMIPS(ST_OTHER)  (((ST_OTHER) & STO_MIPS_ISA) == STO_MICROMIPS)
1974 
1975 // private
1976 unsigned
1977 ObjectFileELF::ParseSymbols (Symtab *symtab,
1978                              user_id_t start_id,
1979                              SectionList *section_list,
1980                              const size_t num_symbols,
1981                              const DataExtractor &symtab_data,
1982                              const DataExtractor &strtab_data)
1983 {
1984     ELFSymbol symbol;
1985     lldb::offset_t offset = 0;
1986 
1987     static ConstString text_section_name(".text");
1988     static ConstString init_section_name(".init");
1989     static ConstString fini_section_name(".fini");
1990     static ConstString ctors_section_name(".ctors");
1991     static ConstString dtors_section_name(".dtors");
1992 
1993     static ConstString data_section_name(".data");
1994     static ConstString rodata_section_name(".rodata");
1995     static ConstString rodata1_section_name(".rodata1");
1996     static ConstString data2_section_name(".data1");
1997     static ConstString bss_section_name(".bss");
1998     static ConstString opd_section_name(".opd");    // For ppc64
1999 
2000     // On Android the oatdata and the oatexec symbols in system@framework@boot.oat covers the full
2001     // .text section what causes issues with displaying unusable symbol name to the user and very
2002     // slow unwinding speed because the instruction emulation based unwind plans try to emulate all
2003     // instructions in these symbols. Don't add these symbols to the symbol list as they have no
2004     // use for the debugger and they are causing a lot of trouble.
2005     // Filtering can't be restricted to Android because this special object file don't contain the
2006     // note section specifying the environment to Android but the custom extension and file name
2007     // makes it highly unlikely that this will collide with anything else.
2008     bool skip_oatdata_oatexec = m_file.GetFilename() == ConstString("system@framework@boot.oat");
2009 
2010     ArchSpec arch;
2011     GetArchitecture(arch);
2012 
2013     // Local cache to avoid doing a FindSectionByName for each symbol. The "const char*" key must
2014     // came from a ConstString object so they can be compared by pointer
2015     std::unordered_map<const char*, lldb::SectionSP> section_name_to_section;
2016 
2017     unsigned i;
2018     for (i = 0; i < num_symbols; ++i)
2019     {
2020         if (symbol.Parse(symtab_data, &offset) == false)
2021             break;
2022 
2023         const char *symbol_name = strtab_data.PeekCStr(symbol.st_name);
2024 
2025         // No need to add non-section symbols that have no names
2026         if (symbol.getType() != STT_SECTION &&
2027             (symbol_name == NULL || symbol_name[0] == '\0'))
2028             continue;
2029 
2030         // Skipping oatdata and oatexec sections if it is requested. See details above the
2031         // definition of skip_oatdata_oatexec for the reasons.
2032         if (skip_oatdata_oatexec && (::strcmp(symbol_name, "oatdata") == 0 || ::strcmp(symbol_name, "oatexec") == 0))
2033             continue;
2034 
2035         SectionSP symbol_section_sp;
2036         SymbolType symbol_type = eSymbolTypeInvalid;
2037         Elf64_Half symbol_idx = symbol.st_shndx;
2038 
2039         switch (symbol_idx)
2040         {
2041         case SHN_ABS:
2042             symbol_type = eSymbolTypeAbsolute;
2043             break;
2044         case SHN_UNDEF:
2045             symbol_type = eSymbolTypeUndefined;
2046             break;
2047         default:
2048             symbol_section_sp = section_list->GetSectionAtIndex(symbol_idx);
2049             break;
2050         }
2051 
2052         // If a symbol is undefined do not process it further even if it has a STT type
2053         if (symbol_type != eSymbolTypeUndefined)
2054         {
2055             switch (symbol.getType())
2056             {
2057             default:
2058             case STT_NOTYPE:
2059                 // The symbol's type is not specified.
2060                 break;
2061 
2062             case STT_OBJECT:
2063                 // The symbol is associated with a data object, such as a variable,
2064                 // an array, etc.
2065                 symbol_type = eSymbolTypeData;
2066                 break;
2067 
2068             case STT_FUNC:
2069                 // The symbol is associated with a function or other executable code.
2070                 symbol_type = eSymbolTypeCode;
2071                 break;
2072 
2073             case STT_SECTION:
2074                 // The symbol is associated with a section. Symbol table entries of
2075                 // this type exist primarily for relocation and normally have
2076                 // STB_LOCAL binding.
2077                 break;
2078 
2079             case STT_FILE:
2080                 // Conventionally, the symbol's name gives the name of the source
2081                 // file associated with the object file. A file symbol has STB_LOCAL
2082                 // binding, its section index is SHN_ABS, and it precedes the other
2083                 // STB_LOCAL symbols for the file, if it is present.
2084                 symbol_type = eSymbolTypeSourceFile;
2085                 break;
2086 
2087             case STT_GNU_IFUNC:
2088                 // The symbol is associated with an indirect function. The actual
2089                 // function will be resolved if it is referenced.
2090                 symbol_type = eSymbolTypeResolver;
2091                 break;
2092             }
2093         }
2094 
2095         if (symbol_type == eSymbolTypeInvalid)
2096         {
2097             if (symbol_section_sp)
2098             {
2099                 const ConstString &sect_name = symbol_section_sp->GetName();
2100                 if (sect_name == text_section_name ||
2101                     sect_name == init_section_name ||
2102                     sect_name == fini_section_name ||
2103                     sect_name == ctors_section_name ||
2104                     sect_name == dtors_section_name)
2105                 {
2106                     symbol_type = eSymbolTypeCode;
2107                 }
2108                 else if (sect_name == data_section_name ||
2109                          sect_name == data2_section_name ||
2110                          sect_name == rodata_section_name ||
2111                          sect_name == rodata1_section_name ||
2112                          sect_name == bss_section_name)
2113                 {
2114                     symbol_type = eSymbolTypeData;
2115                 }
2116             }
2117         }
2118 
2119         int64_t symbol_value_offset = 0;
2120         uint32_t additional_flags = 0;
2121 
2122         if (arch.IsValid())
2123         {
2124             if (arch.GetMachine() == llvm::Triple::arm)
2125             {
2126                 if (symbol.getBinding() == STB_LOCAL)
2127                 {
2128                     char mapping_symbol = FindArmAarch64MappingSymbol(symbol_name);
2129                     if (symbol_type == eSymbolTypeCode)
2130                     {
2131                         switch (mapping_symbol)
2132                         {
2133                             case 'a':
2134                                 // $a[.<any>]* - marks an ARM instruction sequence
2135                                 m_address_class_map[symbol.st_value] = eAddressClassCode;
2136                                 break;
2137                             case 'b':
2138                             case 't':
2139                                 // $b[.<any>]* - marks a THUMB BL instruction sequence
2140                                 // $t[.<any>]* - marks a THUMB instruction sequence
2141                                 m_address_class_map[symbol.st_value] = eAddressClassCodeAlternateISA;
2142                                 break;
2143                             case 'd':
2144                                 // $d[.<any>]* - marks a data item sequence (e.g. lit pool)
2145                                 m_address_class_map[symbol.st_value] = eAddressClassData;
2146                                 break;
2147                         }
2148                     }
2149                     if (mapping_symbol)
2150                         continue;
2151                 }
2152             }
2153             else if (arch.GetMachine() == llvm::Triple::aarch64)
2154             {
2155                 if (symbol.getBinding() == STB_LOCAL)
2156                 {
2157                     char mapping_symbol = FindArmAarch64MappingSymbol(symbol_name);
2158                     if (symbol_type == eSymbolTypeCode)
2159                     {
2160                         switch (mapping_symbol)
2161                         {
2162                             case 'x':
2163                                 // $x[.<any>]* - marks an A64 instruction sequence
2164                                 m_address_class_map[symbol.st_value] = eAddressClassCode;
2165                                 break;
2166                             case 'd':
2167                                 // $d[.<any>]* - marks a data item sequence (e.g. lit pool)
2168                                 m_address_class_map[symbol.st_value] = eAddressClassData;
2169                                 break;
2170                         }
2171                     }
2172                     if (mapping_symbol)
2173                         continue;
2174                 }
2175             }
2176 
2177             if (arch.GetMachine() == llvm::Triple::arm)
2178             {
2179                 if (symbol_type == eSymbolTypeCode)
2180                 {
2181                     if (symbol.st_value & 1)
2182                     {
2183                         // Subtracting 1 from the address effectively unsets
2184                         // the low order bit, which results in the address
2185                         // actually pointing to the beginning of the symbol.
2186                         // This delta will be used below in conjunction with
2187                         // symbol.st_value to produce the final symbol_value
2188                         // that we store in the symtab.
2189                         symbol_value_offset = -1;
2190                         m_address_class_map[symbol.st_value^1] = eAddressClassCodeAlternateISA;
2191                     }
2192                     else
2193                     {
2194                         // This address is ARM
2195                         m_address_class_map[symbol.st_value] = eAddressClassCode;
2196                     }
2197                 }
2198             }
2199 
2200             /*
2201              * MIPS:
2202              * The bit #0 of an address is used for ISA mode (1 for microMIPS, 0 for MIPS).
2203              * This allows processer to switch between microMIPS and MIPS without any need
2204              * for special mode-control register. However, apart from .debug_line, none of
2205              * the ELF/DWARF sections set the ISA bit (for symbol or section). Use st_other
2206              * flag to check whether the symbol is microMIPS and then set the address class
2207              * accordingly.
2208             */
2209             const llvm::Triple::ArchType llvm_arch = arch.GetMachine();
2210             if (llvm_arch == llvm::Triple::mips || llvm_arch == llvm::Triple::mipsel
2211                 || llvm_arch == llvm::Triple::mips64 || llvm_arch == llvm::Triple::mips64el)
2212             {
2213                 if (IS_MICROMIPS(symbol.st_other))
2214                     m_address_class_map[symbol.st_value] = eAddressClassCodeAlternateISA;
2215                 else if ((symbol.st_value & 1) && (symbol_type == eSymbolTypeCode))
2216                 {
2217                     symbol.st_value = symbol.st_value & (~1ull);
2218                     m_address_class_map[symbol.st_value] = eAddressClassCodeAlternateISA;
2219                 }
2220                 else
2221                 {
2222                     if (symbol_type == eSymbolTypeCode)
2223                         m_address_class_map[symbol.st_value] = eAddressClassCode;
2224                     else if (symbol_type == eSymbolTypeData)
2225                         m_address_class_map[symbol.st_value] = eAddressClassData;
2226                     else
2227                         m_address_class_map[symbol.st_value] = eAddressClassUnknown;
2228                 }
2229             }
2230         }
2231 
2232         // symbol_value_offset may contain 0 for ARM symbols or -1 for
2233         // THUMB symbols. See above for more details.
2234         uint64_t symbol_value = symbol.st_value + symbol_value_offset;
2235         if (symbol_section_sp && CalculateType() != ObjectFile::Type::eTypeObjectFile)
2236             symbol_value -= symbol_section_sp->GetFileAddress();
2237 
2238         if (symbol_section_sp)
2239         {
2240             ModuleSP module_sp(GetModule());
2241             if (module_sp)
2242             {
2243                 SectionList *module_section_list = module_sp->GetSectionList();
2244                 if (module_section_list && module_section_list != section_list)
2245                 {
2246                     const ConstString &sect_name = symbol_section_sp->GetName();
2247                     auto section_it = section_name_to_section.find(sect_name.GetCString());
2248                     if (section_it == section_name_to_section.end())
2249                         section_it = section_name_to_section.emplace(
2250                             sect_name.GetCString(),
2251                             module_section_list->FindSectionByName (sect_name)).first;
2252                     if (section_it->second && section_it->second->GetFileSize())
2253                         symbol_section_sp = section_it->second;
2254                 }
2255             }
2256         }
2257 
2258         bool is_global = symbol.getBinding() == STB_GLOBAL;
2259         uint32_t flags = symbol.st_other << 8 | symbol.st_info | additional_flags;
2260         bool is_mangled = symbol_name ? (symbol_name[0] == '_' && symbol_name[1] == 'Z') : false;
2261 
2262         llvm::StringRef symbol_ref(symbol_name);
2263 
2264         // Symbol names may contain @VERSION suffixes. Find those and strip them temporarily.
2265         size_t version_pos = symbol_ref.find('@');
2266         bool has_suffix = version_pos != llvm::StringRef::npos;
2267         llvm::StringRef symbol_bare = symbol_ref.substr(0, version_pos);
2268         Mangled mangled(ConstString(symbol_bare), is_mangled);
2269 
2270         // Now append the suffix back to mangled and unmangled names. Only do it if the
2271         // demangling was successful (string is not empty).
2272         if (has_suffix)
2273         {
2274             llvm::StringRef suffix = symbol_ref.substr(version_pos);
2275 
2276             llvm::StringRef mangled_name = mangled.GetMangledName().GetStringRef();
2277             if (! mangled_name.empty())
2278                 mangled.SetMangledName( ConstString((mangled_name + suffix).str()) );
2279 
2280             ConstString demangled = mangled.GetDemangledName(lldb::eLanguageTypeUnknown);
2281             llvm::StringRef demangled_name = demangled.GetStringRef();
2282             if (!demangled_name.empty())
2283                 mangled.SetDemangledName( ConstString((demangled_name + suffix).str()) );
2284         }
2285 
2286         // In ELF all symbol should have a valid size but it is not true for some code symbols
2287         // coming from hand written assembly. As none of the code symbol should have 0 size we try
2288         // to calculate the size for these symbols in the symtab with saying that their original
2289         // size is not valid.
2290         bool symbol_size_valid = symbol.st_size != 0 || symbol_type != eSymbolTypeCode;
2291 
2292         Symbol dc_symbol(
2293             i + start_id,       // ID is the original symbol table index.
2294             mangled,
2295             symbol_type,        // Type of this symbol
2296             is_global,          // Is this globally visible?
2297             false,              // Is this symbol debug info?
2298             false,              // Is this symbol a trampoline?
2299             false,              // Is this symbol artificial?
2300             AddressRange(
2301                 symbol_section_sp,  // Section in which this symbol is defined or null.
2302                 symbol_value,       // Offset in section or symbol value.
2303                 symbol.st_size),    // Size in bytes of this symbol.
2304             symbol_size_valid,      // Symbol size is valid
2305             has_suffix,             // Contains linker annotations?
2306             flags);                 // Symbol flags.
2307         symtab->AddSymbol(dc_symbol);
2308     }
2309     return i;
2310 }
2311 
2312 unsigned
2313 ObjectFileELF::ParseSymbolTable(Symtab *symbol_table,
2314                                 user_id_t start_id,
2315                                 lldb_private::Section *symtab)
2316 {
2317     if (symtab->GetObjectFile() != this)
2318     {
2319         // If the symbol table section is owned by a different object file, have it do the
2320         // parsing.
2321         ObjectFileELF *obj_file_elf = static_cast<ObjectFileELF *>(symtab->GetObjectFile());
2322         return obj_file_elf->ParseSymbolTable (symbol_table, start_id, symtab);
2323     }
2324 
2325     // Get section list for this object file.
2326     SectionList *section_list = m_sections_ap.get();
2327     if (!section_list)
2328         return 0;
2329 
2330     user_id_t symtab_id = symtab->GetID();
2331     const ELFSectionHeaderInfo *symtab_hdr = GetSectionHeaderByIndex(symtab_id);
2332     assert(symtab_hdr->sh_type == SHT_SYMTAB ||
2333            symtab_hdr->sh_type == SHT_DYNSYM);
2334 
2335     // sh_link: section header index of associated string table.
2336     // Section ID's are ones based.
2337     user_id_t strtab_id = symtab_hdr->sh_link + 1;
2338     Section *strtab = section_list->FindSectionByID(strtab_id).get();
2339 
2340     if (symtab && strtab)
2341     {
2342         assert (symtab->GetObjectFile() == this);
2343         assert (strtab->GetObjectFile() == this);
2344 
2345         DataExtractor symtab_data;
2346         DataExtractor strtab_data;
2347         if (ReadSectionData(symtab, symtab_data) &&
2348             ReadSectionData(strtab, strtab_data))
2349         {
2350             size_t num_symbols = symtab_data.GetByteSize() / symtab_hdr->sh_entsize;
2351 
2352             return ParseSymbols(symbol_table, start_id, section_list,
2353                                 num_symbols, symtab_data, strtab_data);
2354         }
2355     }
2356 
2357     return 0;
2358 }
2359 
2360 size_t
2361 ObjectFileELF::ParseDynamicSymbols()
2362 {
2363     if (m_dynamic_symbols.size())
2364         return m_dynamic_symbols.size();
2365 
2366     SectionList *section_list = GetSectionList();
2367     if (!section_list)
2368         return 0;
2369 
2370     // Find the SHT_DYNAMIC section.
2371     Section *dynsym = section_list->FindSectionByType (eSectionTypeELFDynamicLinkInfo, true).get();
2372     if (!dynsym)
2373         return 0;
2374     assert (dynsym->GetObjectFile() == this);
2375 
2376     ELFDynamic symbol;
2377     DataExtractor dynsym_data;
2378     if (ReadSectionData(dynsym, dynsym_data))
2379     {
2380         const lldb::offset_t section_size = dynsym_data.GetByteSize();
2381         lldb::offset_t cursor = 0;
2382 
2383         while (cursor < section_size)
2384         {
2385             if (!symbol.Parse(dynsym_data, &cursor))
2386                 break;
2387 
2388             m_dynamic_symbols.push_back(symbol);
2389         }
2390     }
2391 
2392     return m_dynamic_symbols.size();
2393 }
2394 
2395 const ELFDynamic *
2396 ObjectFileELF::FindDynamicSymbol(unsigned tag)
2397 {
2398     if (!ParseDynamicSymbols())
2399         return NULL;
2400 
2401     DynamicSymbolCollIter I = m_dynamic_symbols.begin();
2402     DynamicSymbolCollIter E = m_dynamic_symbols.end();
2403     for ( ; I != E; ++I)
2404     {
2405         ELFDynamic *symbol = &*I;
2406 
2407         if (symbol->d_tag == tag)
2408             return symbol;
2409     }
2410 
2411     return NULL;
2412 }
2413 
2414 unsigned
2415 ObjectFileELF::PLTRelocationType()
2416 {
2417     // DT_PLTREL
2418     //  This member specifies the type of relocation entry to which the
2419     //  procedure linkage table refers. The d_val member holds DT_REL or
2420     //  DT_RELA, as appropriate. All relocations in a procedure linkage table
2421     //  must use the same relocation.
2422     const ELFDynamic *symbol = FindDynamicSymbol(DT_PLTREL);
2423 
2424     if (symbol)
2425         return symbol->d_val;
2426 
2427     return 0;
2428 }
2429 
2430 // Returns the size of the normal plt entries and the offset of the first normal plt entry. The
2431 // 0th entry in the plt table is usually a resolution entry which have different size in some
2432 // architectures then the rest of the plt entries.
2433 static std::pair<uint64_t, uint64_t>
2434 GetPltEntrySizeAndOffset(const ELFSectionHeader* rel_hdr, const ELFSectionHeader* plt_hdr)
2435 {
2436     const elf_xword num_relocations = rel_hdr->sh_size / rel_hdr->sh_entsize;
2437 
2438     // Clang 3.3 sets entsize to 4 for 32-bit binaries, but the plt entries are 16 bytes.
2439     // So round the entsize up by the alignment if addralign is set.
2440     elf_xword plt_entsize = plt_hdr->sh_addralign ?
2441         llvm::alignTo (plt_hdr->sh_entsize, plt_hdr->sh_addralign) : plt_hdr->sh_entsize;
2442 
2443     if (plt_entsize == 0)
2444     {
2445         // The linker haven't set the plt_hdr->sh_entsize field. Try to guess the size of the plt
2446         // entries based on the number of entries and the size of the plt section with the
2447         // assumption that the size of the 0th entry is at least as big as the size of the normal
2448         // entries and it isn't much bigger then that.
2449         if (plt_hdr->sh_addralign)
2450             plt_entsize = plt_hdr->sh_size / plt_hdr->sh_addralign / (num_relocations + 1) * plt_hdr->sh_addralign;
2451         else
2452             plt_entsize = plt_hdr->sh_size / (num_relocations + 1);
2453     }
2454 
2455     elf_xword plt_offset = plt_hdr->sh_size - num_relocations * plt_entsize;
2456 
2457     return std::make_pair(plt_entsize, plt_offset);
2458 }
2459 
2460 static unsigned
2461 ParsePLTRelocations(Symtab *symbol_table,
2462                     user_id_t start_id,
2463                     unsigned rel_type,
2464                     const ELFHeader *hdr,
2465                     const ELFSectionHeader *rel_hdr,
2466                     const ELFSectionHeader *plt_hdr,
2467                     const ELFSectionHeader *sym_hdr,
2468                     const lldb::SectionSP &plt_section_sp,
2469                     DataExtractor &rel_data,
2470                     DataExtractor &symtab_data,
2471                     DataExtractor &strtab_data)
2472 {
2473     ELFRelocation rel(rel_type);
2474     ELFSymbol symbol;
2475     lldb::offset_t offset = 0;
2476 
2477     uint64_t plt_offset, plt_entsize;
2478     std::tie(plt_entsize, plt_offset) = GetPltEntrySizeAndOffset(rel_hdr, plt_hdr);
2479     const elf_xword num_relocations = rel_hdr->sh_size / rel_hdr->sh_entsize;
2480 
2481     typedef unsigned (*reloc_info_fn)(const ELFRelocation &rel);
2482     reloc_info_fn reloc_type;
2483     reloc_info_fn reloc_symbol;
2484 
2485     if (hdr->Is32Bit())
2486     {
2487         reloc_type = ELFRelocation::RelocType32;
2488         reloc_symbol = ELFRelocation::RelocSymbol32;
2489     }
2490     else
2491     {
2492         reloc_type = ELFRelocation::RelocType64;
2493         reloc_symbol = ELFRelocation::RelocSymbol64;
2494     }
2495 
2496     unsigned slot_type = hdr->GetRelocationJumpSlotType();
2497     unsigned i;
2498     for (i = 0; i < num_relocations; ++i)
2499     {
2500         if (rel.Parse(rel_data, &offset) == false)
2501             break;
2502 
2503         if (reloc_type(rel) != slot_type)
2504             continue;
2505 
2506         lldb::offset_t symbol_offset = reloc_symbol(rel) * sym_hdr->sh_entsize;
2507         if (!symbol.Parse(symtab_data, &symbol_offset))
2508             break;
2509 
2510         const char *symbol_name = strtab_data.PeekCStr(symbol.st_name);
2511         bool is_mangled = symbol_name ? (symbol_name[0] == '_' && symbol_name[1] == 'Z') : false;
2512         uint64_t plt_index = plt_offset + i * plt_entsize;
2513 
2514         Symbol jump_symbol(
2515             i + start_id,    // Symbol table index
2516             symbol_name,     // symbol name.
2517             is_mangled,      // is the symbol name mangled?
2518             eSymbolTypeTrampoline, // Type of this symbol
2519             false,           // Is this globally visible?
2520             false,           // Is this symbol debug info?
2521             true,            // Is this symbol a trampoline?
2522             true,            // Is this symbol artificial?
2523             plt_section_sp,  // Section in which this symbol is defined or null.
2524             plt_index,       // Offset in section or symbol value.
2525             plt_entsize,     // Size in bytes of this symbol.
2526             true,            // Size is valid
2527             false,           // Contains linker annotations?
2528             0);              // Symbol flags.
2529 
2530         symbol_table->AddSymbol(jump_symbol);
2531     }
2532 
2533     return i;
2534 }
2535 
2536 unsigned
2537 ObjectFileELF::ParseTrampolineSymbols(Symtab *symbol_table,
2538                                       user_id_t start_id,
2539                                       const ELFSectionHeaderInfo *rel_hdr,
2540                                       user_id_t rel_id)
2541 {
2542     assert(rel_hdr->sh_type == SHT_RELA || rel_hdr->sh_type == SHT_REL);
2543 
2544     // The link field points to the associated symbol table. The info field
2545     // points to the section holding the plt.
2546     user_id_t symtab_id = rel_hdr->sh_link;
2547     user_id_t plt_id = rel_hdr->sh_info;
2548 
2549     // If the link field doesn't point to the appropriate symbol name table then
2550     // try to find it by name as some compiler don't fill in the link fields.
2551     if (!symtab_id)
2552         symtab_id = GetSectionIndexByName(".dynsym");
2553     if (!plt_id)
2554         plt_id = GetSectionIndexByName(".plt");
2555 
2556     if (!symtab_id || !plt_id)
2557         return 0;
2558 
2559     // Section ID's are ones based;
2560     symtab_id++;
2561     plt_id++;
2562 
2563     const ELFSectionHeaderInfo *plt_hdr = GetSectionHeaderByIndex(plt_id);
2564     if (!plt_hdr)
2565         return 0;
2566 
2567     const ELFSectionHeaderInfo *sym_hdr = GetSectionHeaderByIndex(symtab_id);
2568     if (!sym_hdr)
2569         return 0;
2570 
2571     SectionList *section_list = m_sections_ap.get();
2572     if (!section_list)
2573         return 0;
2574 
2575     Section *rel_section = section_list->FindSectionByID(rel_id).get();
2576     if (!rel_section)
2577         return 0;
2578 
2579     SectionSP plt_section_sp (section_list->FindSectionByID(plt_id));
2580     if (!plt_section_sp)
2581         return 0;
2582 
2583     Section *symtab = section_list->FindSectionByID(symtab_id).get();
2584     if (!symtab)
2585         return 0;
2586 
2587     // sh_link points to associated string table.
2588     Section *strtab = section_list->FindSectionByID(sym_hdr->sh_link + 1).get();
2589     if (!strtab)
2590         return 0;
2591 
2592     DataExtractor rel_data;
2593     if (!ReadSectionData(rel_section, rel_data))
2594         return 0;
2595 
2596     DataExtractor symtab_data;
2597     if (!ReadSectionData(symtab, symtab_data))
2598         return 0;
2599 
2600     DataExtractor strtab_data;
2601     if (!ReadSectionData(strtab, strtab_data))
2602         return 0;
2603 
2604     unsigned rel_type = PLTRelocationType();
2605     if (!rel_type)
2606         return 0;
2607 
2608     return ParsePLTRelocations (symbol_table,
2609                                 start_id,
2610                                 rel_type,
2611                                 &m_header,
2612                                 rel_hdr,
2613                                 plt_hdr,
2614                                 sym_hdr,
2615                                 plt_section_sp,
2616                                 rel_data,
2617                                 symtab_data,
2618                                 strtab_data);
2619 }
2620 
2621 unsigned
2622 ObjectFileELF::RelocateSection(Symtab* symtab, const ELFHeader *hdr, const ELFSectionHeader *rel_hdr,
2623                 const ELFSectionHeader *symtab_hdr, const ELFSectionHeader *debug_hdr,
2624                 DataExtractor &rel_data, DataExtractor &symtab_data,
2625                 DataExtractor &debug_data, Section* rel_section)
2626 {
2627     ELFRelocation rel(rel_hdr->sh_type);
2628     lldb::addr_t offset = 0;
2629     const unsigned num_relocations = rel_hdr->sh_size / rel_hdr->sh_entsize;
2630     typedef unsigned (*reloc_info_fn)(const ELFRelocation &rel);
2631     reloc_info_fn reloc_type;
2632     reloc_info_fn reloc_symbol;
2633 
2634     if (hdr->Is32Bit())
2635     {
2636         reloc_type = ELFRelocation::RelocType32;
2637         reloc_symbol = ELFRelocation::RelocSymbol32;
2638     }
2639     else
2640     {
2641         reloc_type = ELFRelocation::RelocType64;
2642         reloc_symbol = ELFRelocation::RelocSymbol64;
2643     }
2644 
2645     for (unsigned i = 0; i < num_relocations; ++i)
2646     {
2647         if (rel.Parse(rel_data, &offset) == false)
2648             break;
2649 
2650         Symbol* symbol = NULL;
2651 
2652         if (hdr->Is32Bit())
2653         {
2654             switch (reloc_type(rel)) {
2655             case R_386_32:
2656             case R_386_PC32:
2657             default:
2658                 assert(false && "unexpected relocation type");
2659             }
2660         } else {
2661             switch (reloc_type(rel)) {
2662             case R_X86_64_64:
2663             {
2664                 symbol = symtab->FindSymbolByID(reloc_symbol(rel));
2665                 if (symbol)
2666                 {
2667                     addr_t value = symbol->GetAddressRef().GetFileAddress();
2668                     DataBufferSP& data_buffer_sp = debug_data.GetSharedDataBuffer();
2669                     uint64_t* dst = reinterpret_cast<uint64_t*>(data_buffer_sp->GetBytes() + rel_section->GetFileOffset() + ELFRelocation::RelocOffset64(rel));
2670                     *dst = value + ELFRelocation::RelocAddend64(rel);
2671                 }
2672                 break;
2673             }
2674             case R_X86_64_32:
2675             case R_X86_64_32S:
2676             {
2677                 symbol = symtab->FindSymbolByID(reloc_symbol(rel));
2678                 if (symbol)
2679                 {
2680                     addr_t value = symbol->GetAddressRef().GetFileAddress();
2681                     value += ELFRelocation::RelocAddend32(rel);
2682                     assert((reloc_type(rel) == R_X86_64_32 && (value <= UINT32_MAX)) ||
2683                            (reloc_type(rel) == R_X86_64_32S &&
2684                             ((int64_t)value <= INT32_MAX && (int64_t)value >= INT32_MIN)));
2685                     uint32_t truncated_addr = (value & 0xFFFFFFFF);
2686                     DataBufferSP& data_buffer_sp = debug_data.GetSharedDataBuffer();
2687                     uint32_t* dst = reinterpret_cast<uint32_t*>(data_buffer_sp->GetBytes() + rel_section->GetFileOffset() + ELFRelocation::RelocOffset32(rel));
2688                     *dst = truncated_addr;
2689                 }
2690                 break;
2691             }
2692             case R_X86_64_PC32:
2693             default:
2694                 assert(false && "unexpected relocation type");
2695             }
2696         }
2697     }
2698 
2699     return 0;
2700 }
2701 
2702 unsigned
2703 ObjectFileELF::RelocateDebugSections(const ELFSectionHeader *rel_hdr, user_id_t rel_id)
2704 {
2705     assert(rel_hdr->sh_type == SHT_RELA || rel_hdr->sh_type == SHT_REL);
2706 
2707     // Parse in the section list if needed.
2708     SectionList *section_list = GetSectionList();
2709     if (!section_list)
2710         return 0;
2711 
2712     // Section ID's are ones based.
2713     user_id_t symtab_id = rel_hdr->sh_link + 1;
2714     user_id_t debug_id = rel_hdr->sh_info + 1;
2715 
2716     const ELFSectionHeader *symtab_hdr = GetSectionHeaderByIndex(symtab_id);
2717     if (!symtab_hdr)
2718         return 0;
2719 
2720     const ELFSectionHeader *debug_hdr = GetSectionHeaderByIndex(debug_id);
2721     if (!debug_hdr)
2722         return 0;
2723 
2724     Section *rel = section_list->FindSectionByID(rel_id).get();
2725     if (!rel)
2726         return 0;
2727 
2728     Section *symtab = section_list->FindSectionByID(symtab_id).get();
2729     if (!symtab)
2730         return 0;
2731 
2732     Section *debug = section_list->FindSectionByID(debug_id).get();
2733     if (!debug)
2734         return 0;
2735 
2736     DataExtractor rel_data;
2737     DataExtractor symtab_data;
2738     DataExtractor debug_data;
2739 
2740     if (ReadSectionData(rel, rel_data) &&
2741         ReadSectionData(symtab, symtab_data) &&
2742         ReadSectionData(debug, debug_data))
2743     {
2744         RelocateSection(m_symtab_ap.get(), &m_header, rel_hdr, symtab_hdr, debug_hdr,
2745                         rel_data, symtab_data, debug_data, debug);
2746     }
2747 
2748     return 0;
2749 }
2750 
2751 Symtab *
2752 ObjectFileELF::GetSymtab()
2753 {
2754     ModuleSP module_sp(GetModule());
2755     if (!module_sp)
2756         return NULL;
2757 
2758     // We always want to use the main object file so we (hopefully) only have one cached copy
2759     // of our symtab, dynamic sections, etc.
2760     ObjectFile *module_obj_file = module_sp->GetObjectFile();
2761     if (module_obj_file && module_obj_file != this)
2762         return module_obj_file->GetSymtab();
2763 
2764     if (m_symtab_ap.get() == NULL)
2765     {
2766         SectionList *section_list = module_sp->GetSectionList();
2767         if (!section_list)
2768             return NULL;
2769 
2770         uint64_t symbol_id = 0;
2771         lldb_private::Mutex::Locker locker(module_sp->GetMutex());
2772 
2773         // Sharable objects and dynamic executables usually have 2 distinct symbol
2774         // tables, one named ".symtab", and the other ".dynsym". The dynsym is a smaller
2775         // version of the symtab that only contains global symbols. The information found
2776         // in the dynsym is therefore also found in the symtab, while the reverse is not
2777         // necessarily true.
2778         Section *symtab = section_list->FindSectionByType (eSectionTypeELFSymbolTable, true).get();
2779         if (!symtab)
2780         {
2781             // The symtab section is non-allocable and can be stripped, so if it doesn't exist
2782             // then use the dynsym section which should always be there.
2783             symtab = section_list->FindSectionByType (eSectionTypeELFDynamicSymbols, true).get();
2784         }
2785         if (symtab)
2786         {
2787             m_symtab_ap.reset(new Symtab(symtab->GetObjectFile()));
2788             symbol_id += ParseSymbolTable (m_symtab_ap.get(), symbol_id, symtab);
2789         }
2790 
2791         // DT_JMPREL
2792         //      If present, this entry's d_ptr member holds the address of relocation
2793         //      entries associated solely with the procedure linkage table. Separating
2794         //      these relocation entries lets the dynamic linker ignore them during
2795         //      process initialization, if lazy binding is enabled. If this entry is
2796         //      present, the related entries of types DT_PLTRELSZ and DT_PLTREL must
2797         //      also be present.
2798         const ELFDynamic *symbol = FindDynamicSymbol(DT_JMPREL);
2799         if (symbol)
2800         {
2801             // Synthesize trampoline symbols to help navigate the PLT.
2802             addr_t addr = symbol->d_ptr;
2803             Section *reloc_section = section_list->FindSectionContainingFileAddress(addr).get();
2804             if (reloc_section)
2805             {
2806                 user_id_t reloc_id = reloc_section->GetID();
2807                 const ELFSectionHeaderInfo *reloc_header = GetSectionHeaderByIndex(reloc_id);
2808                 assert(reloc_header);
2809 
2810                 if (m_symtab_ap == nullptr)
2811                     m_symtab_ap.reset(new Symtab(reloc_section->GetObjectFile()));
2812 
2813                 ParseTrampolineSymbols (m_symtab_ap.get(), symbol_id, reloc_header, reloc_id);
2814             }
2815         }
2816 
2817         // If we still don't have any symtab then create an empty instance to avoid do the section
2818         // lookup next time.
2819         if (m_symtab_ap == nullptr)
2820             m_symtab_ap.reset(new Symtab(this));
2821 
2822         m_symtab_ap->CalculateSymbolSizes();
2823     }
2824 
2825     for (SectionHeaderCollIter I = m_section_headers.begin();
2826          I != m_section_headers.end(); ++I)
2827     {
2828         if (I->sh_type == SHT_RELA || I->sh_type == SHT_REL)
2829         {
2830             if (CalculateType() == eTypeObjectFile)
2831             {
2832                 const char *section_name = I->section_name.AsCString("");
2833                 if (strstr(section_name, ".rela.debug") ||
2834                     strstr(section_name, ".rel.debug"))
2835                 {
2836                     const ELFSectionHeader &reloc_header = *I;
2837                     user_id_t reloc_id = SectionIndex(I);
2838                     RelocateDebugSections(&reloc_header, reloc_id);
2839                 }
2840             }
2841         }
2842     }
2843     return m_symtab_ap.get();
2844 }
2845 
2846 Symbol *
2847 ObjectFileELF::ResolveSymbolForAddress(const Address& so_addr, bool verify_unique)
2848 {
2849     if (!m_symtab_ap.get())
2850         return nullptr; // GetSymtab() should be called first.
2851 
2852     const SectionList *section_list = GetSectionList();
2853     if (!section_list)
2854         return nullptr;
2855 
2856     if (DWARFCallFrameInfo *eh_frame = GetUnwindTable().GetEHFrameInfo())
2857     {
2858         AddressRange range;
2859         if (eh_frame->GetAddressRange (so_addr, range))
2860         {
2861             const addr_t file_addr = range.GetBaseAddress().GetFileAddress();
2862             Symbol * symbol = verify_unique ? m_symtab_ap->FindSymbolContainingFileAddress(file_addr) : nullptr;
2863             if (symbol)
2864                 return symbol;
2865 
2866             // Note that a (stripped) symbol won't be found by GetSymtab()...
2867             lldb::SectionSP eh_sym_section_sp = section_list->FindSectionContainingFileAddress(file_addr);
2868             if (eh_sym_section_sp.get())
2869             {
2870                 addr_t section_base = eh_sym_section_sp->GetFileAddress();
2871                 addr_t offset = file_addr - section_base;
2872                 uint64_t symbol_id = m_symtab_ap->GetNumSymbols();
2873 
2874                 Symbol eh_symbol(
2875                         symbol_id,            // Symbol table index.
2876                         "???",                // Symbol name.
2877                         false,                // Is the symbol name mangled?
2878                         eSymbolTypeCode,      // Type of this symbol.
2879                         true,                 // Is this globally visible?
2880                         false,                // Is this symbol debug info?
2881                         false,                // Is this symbol a trampoline?
2882                         true,                 // Is this symbol artificial?
2883                         eh_sym_section_sp,    // Section in which this symbol is defined or null.
2884                         offset,               // Offset in section or symbol value.
2885                         range.GetByteSize(),  // Size in bytes of this symbol.
2886                         true,                 // Size is valid.
2887                         false,                // Contains linker annotations?
2888                         0);                   // Symbol flags.
2889                 if (symbol_id == m_symtab_ap->AddSymbol(eh_symbol))
2890                     return m_symtab_ap->SymbolAtIndex(symbol_id);
2891             }
2892         }
2893     }
2894     return nullptr;
2895 }
2896 
2897 
2898 bool
2899 ObjectFileELF::IsStripped ()
2900 {
2901     // TODO: determine this for ELF
2902     return false;
2903 }
2904 
2905 //===----------------------------------------------------------------------===//
2906 // Dump
2907 //
2908 // Dump the specifics of the runtime file container (such as any headers
2909 // segments, sections, etc).
2910 //----------------------------------------------------------------------
2911 void
2912 ObjectFileELF::Dump(Stream *s)
2913 {
2914     DumpELFHeader(s, m_header);
2915     s->EOL();
2916     DumpELFProgramHeaders(s);
2917     s->EOL();
2918     DumpELFSectionHeaders(s);
2919     s->EOL();
2920     SectionList *section_list = GetSectionList();
2921     if (section_list)
2922         section_list->Dump(s, NULL, true, UINT32_MAX);
2923     Symtab *symtab = GetSymtab();
2924     if (symtab)
2925         symtab->Dump(s, NULL, eSortOrderNone);
2926     s->EOL();
2927     DumpDependentModules(s);
2928     s->EOL();
2929 }
2930 
2931 //----------------------------------------------------------------------
2932 // DumpELFHeader
2933 //
2934 // Dump the ELF header to the specified output stream
2935 //----------------------------------------------------------------------
2936 void
2937 ObjectFileELF::DumpELFHeader(Stream *s, const ELFHeader &header)
2938 {
2939     s->PutCString("ELF Header\n");
2940     s->Printf("e_ident[EI_MAG0   ] = 0x%2.2x\n", header.e_ident[EI_MAG0]);
2941     s->Printf("e_ident[EI_MAG1   ] = 0x%2.2x '%c'\n",
2942               header.e_ident[EI_MAG1], header.e_ident[EI_MAG1]);
2943     s->Printf("e_ident[EI_MAG2   ] = 0x%2.2x '%c'\n",
2944               header.e_ident[EI_MAG2], header.e_ident[EI_MAG2]);
2945     s->Printf("e_ident[EI_MAG3   ] = 0x%2.2x '%c'\n",
2946               header.e_ident[EI_MAG3], header.e_ident[EI_MAG3]);
2947 
2948     s->Printf("e_ident[EI_CLASS  ] = 0x%2.2x\n", header.e_ident[EI_CLASS]);
2949     s->Printf("e_ident[EI_DATA   ] = 0x%2.2x ", header.e_ident[EI_DATA]);
2950     DumpELFHeader_e_ident_EI_DATA(s, header.e_ident[EI_DATA]);
2951     s->Printf ("\ne_ident[EI_VERSION] = 0x%2.2x\n", header.e_ident[EI_VERSION]);
2952     s->Printf ("e_ident[EI_PAD    ] = 0x%2.2x\n", header.e_ident[EI_PAD]);
2953 
2954     s->Printf("e_type      = 0x%4.4x ", header.e_type);
2955     DumpELFHeader_e_type(s, header.e_type);
2956     s->Printf("\ne_machine   = 0x%4.4x\n", header.e_machine);
2957     s->Printf("e_version   = 0x%8.8x\n", header.e_version);
2958     s->Printf("e_entry     = 0x%8.8" PRIx64 "\n", header.e_entry);
2959     s->Printf("e_phoff     = 0x%8.8" PRIx64 "\n", header.e_phoff);
2960     s->Printf("e_shoff     = 0x%8.8" PRIx64 "\n", header.e_shoff);
2961     s->Printf("e_flags     = 0x%8.8x\n", header.e_flags);
2962     s->Printf("e_ehsize    = 0x%4.4x\n", header.e_ehsize);
2963     s->Printf("e_phentsize = 0x%4.4x\n", header.e_phentsize);
2964     s->Printf("e_phnum     = 0x%4.4x\n", header.e_phnum);
2965     s->Printf("e_shentsize = 0x%4.4x\n", header.e_shentsize);
2966     s->Printf("e_shnum     = 0x%4.4x\n", header.e_shnum);
2967     s->Printf("e_shstrndx  = 0x%4.4x\n", header.e_shstrndx);
2968 }
2969 
2970 //----------------------------------------------------------------------
2971 // DumpELFHeader_e_type
2972 //
2973 // Dump an token value for the ELF header member e_type
2974 //----------------------------------------------------------------------
2975 void
2976 ObjectFileELF::DumpELFHeader_e_type(Stream *s, elf_half e_type)
2977 {
2978     switch (e_type)
2979     {
2980     case ET_NONE:   *s << "ET_NONE"; break;
2981     case ET_REL:    *s << "ET_REL"; break;
2982     case ET_EXEC:   *s << "ET_EXEC"; break;
2983     case ET_DYN:    *s << "ET_DYN"; break;
2984     case ET_CORE:   *s << "ET_CORE"; break;
2985     default:
2986         break;
2987     }
2988 }
2989 
2990 //----------------------------------------------------------------------
2991 // DumpELFHeader_e_ident_EI_DATA
2992 //
2993 // Dump an token value for the ELF header member e_ident[EI_DATA]
2994 //----------------------------------------------------------------------
2995 void
2996 ObjectFileELF::DumpELFHeader_e_ident_EI_DATA(Stream *s, unsigned char ei_data)
2997 {
2998     switch (ei_data)
2999     {
3000     case ELFDATANONE:   *s << "ELFDATANONE"; break;
3001     case ELFDATA2LSB:   *s << "ELFDATA2LSB - Little Endian"; break;
3002     case ELFDATA2MSB:   *s << "ELFDATA2MSB - Big Endian"; break;
3003     default:
3004         break;
3005     }
3006 }
3007 
3008 
3009 //----------------------------------------------------------------------
3010 // DumpELFProgramHeader
3011 //
3012 // Dump a single ELF program header to the specified output stream
3013 //----------------------------------------------------------------------
3014 void
3015 ObjectFileELF::DumpELFProgramHeader(Stream *s, const ELFProgramHeader &ph)
3016 {
3017     DumpELFProgramHeader_p_type(s, ph.p_type);
3018     s->Printf(" %8.8" PRIx64 " %8.8" PRIx64 " %8.8" PRIx64, ph.p_offset, ph.p_vaddr, ph.p_paddr);
3019     s->Printf(" %8.8" PRIx64 " %8.8" PRIx64 " %8.8x (", ph.p_filesz, ph.p_memsz, ph.p_flags);
3020 
3021     DumpELFProgramHeader_p_flags(s, ph.p_flags);
3022     s->Printf(") %8.8" PRIx64, ph.p_align);
3023 }
3024 
3025 //----------------------------------------------------------------------
3026 // DumpELFProgramHeader_p_type
3027 //
3028 // Dump an token value for the ELF program header member p_type which
3029 // describes the type of the program header
3030 // ----------------------------------------------------------------------
3031 void
3032 ObjectFileELF::DumpELFProgramHeader_p_type(Stream *s, elf_word p_type)
3033 {
3034     const int kStrWidth = 15;
3035     switch (p_type)
3036     {
3037     CASE_AND_STREAM(s, PT_NULL        , kStrWidth);
3038     CASE_AND_STREAM(s, PT_LOAD        , kStrWidth);
3039     CASE_AND_STREAM(s, PT_DYNAMIC     , kStrWidth);
3040     CASE_AND_STREAM(s, PT_INTERP      , kStrWidth);
3041     CASE_AND_STREAM(s, PT_NOTE        , kStrWidth);
3042     CASE_AND_STREAM(s, PT_SHLIB       , kStrWidth);
3043     CASE_AND_STREAM(s, PT_PHDR        , kStrWidth);
3044     CASE_AND_STREAM(s, PT_TLS         , kStrWidth);
3045     CASE_AND_STREAM(s, PT_GNU_EH_FRAME, kStrWidth);
3046     default:
3047         s->Printf("0x%8.8x%*s", p_type, kStrWidth - 10, "");
3048         break;
3049     }
3050 }
3051 
3052 
3053 //----------------------------------------------------------------------
3054 // DumpELFProgramHeader_p_flags
3055 //
3056 // Dump an token value for the ELF program header member p_flags
3057 //----------------------------------------------------------------------
3058 void
3059 ObjectFileELF::DumpELFProgramHeader_p_flags(Stream *s, elf_word p_flags)
3060 {
3061     *s  << ((p_flags & PF_X) ? "PF_X" : "    ")
3062         << (((p_flags & PF_X) && (p_flags & PF_W)) ? '+' : ' ')
3063         << ((p_flags & PF_W) ? "PF_W" : "    ")
3064         << (((p_flags & PF_W) && (p_flags & PF_R)) ? '+' : ' ')
3065         << ((p_flags & PF_R) ? "PF_R" : "    ");
3066 }
3067 
3068 //----------------------------------------------------------------------
3069 // DumpELFProgramHeaders
3070 //
3071 // Dump all of the ELF program header to the specified output stream
3072 //----------------------------------------------------------------------
3073 void
3074 ObjectFileELF::DumpELFProgramHeaders(Stream *s)
3075 {
3076     if (!ParseProgramHeaders())
3077         return;
3078 
3079     s->PutCString("Program Headers\n");
3080     s->PutCString("IDX  p_type          p_offset p_vaddr  p_paddr  "
3081                   "p_filesz p_memsz  p_flags                   p_align\n");
3082     s->PutCString("==== --------------- -------- -------- -------- "
3083                   "-------- -------- ------------------------- --------\n");
3084 
3085     uint32_t idx = 0;
3086     for (ProgramHeaderCollConstIter I = m_program_headers.begin();
3087          I != m_program_headers.end(); ++I, ++idx)
3088     {
3089         s->Printf("[%2u] ", idx);
3090         ObjectFileELF::DumpELFProgramHeader(s, *I);
3091         s->EOL();
3092     }
3093 }
3094 
3095 //----------------------------------------------------------------------
3096 // DumpELFSectionHeader
3097 //
3098 // Dump a single ELF section header to the specified output stream
3099 //----------------------------------------------------------------------
3100 void
3101 ObjectFileELF::DumpELFSectionHeader(Stream *s, const ELFSectionHeaderInfo &sh)
3102 {
3103     s->Printf("%8.8x ", sh.sh_name);
3104     DumpELFSectionHeader_sh_type(s, sh.sh_type);
3105     s->Printf(" %8.8" PRIx64 " (", sh.sh_flags);
3106     DumpELFSectionHeader_sh_flags(s, sh.sh_flags);
3107     s->Printf(") %8.8" PRIx64 " %8.8" PRIx64 " %8.8" PRIx64, sh.sh_addr, sh.sh_offset, sh.sh_size);
3108     s->Printf(" %8.8x %8.8x", sh.sh_link, sh.sh_info);
3109     s->Printf(" %8.8" PRIx64 " %8.8" PRIx64, sh.sh_addralign, sh.sh_entsize);
3110 }
3111 
3112 //----------------------------------------------------------------------
3113 // DumpELFSectionHeader_sh_type
3114 //
3115 // Dump an token value for the ELF section header member sh_type which
3116 // describes the type of the section
3117 //----------------------------------------------------------------------
3118 void
3119 ObjectFileELF::DumpELFSectionHeader_sh_type(Stream *s, elf_word sh_type)
3120 {
3121     const int kStrWidth = 12;
3122     switch (sh_type)
3123     {
3124     CASE_AND_STREAM(s, SHT_NULL     , kStrWidth);
3125     CASE_AND_STREAM(s, SHT_PROGBITS , kStrWidth);
3126     CASE_AND_STREAM(s, SHT_SYMTAB   , kStrWidth);
3127     CASE_AND_STREAM(s, SHT_STRTAB   , kStrWidth);
3128     CASE_AND_STREAM(s, SHT_RELA     , kStrWidth);
3129     CASE_AND_STREAM(s, SHT_HASH     , kStrWidth);
3130     CASE_AND_STREAM(s, SHT_DYNAMIC  , kStrWidth);
3131     CASE_AND_STREAM(s, SHT_NOTE     , kStrWidth);
3132     CASE_AND_STREAM(s, SHT_NOBITS   , kStrWidth);
3133     CASE_AND_STREAM(s, SHT_REL      , kStrWidth);
3134     CASE_AND_STREAM(s, SHT_SHLIB    , kStrWidth);
3135     CASE_AND_STREAM(s, SHT_DYNSYM   , kStrWidth);
3136     CASE_AND_STREAM(s, SHT_LOPROC   , kStrWidth);
3137     CASE_AND_STREAM(s, SHT_HIPROC   , kStrWidth);
3138     CASE_AND_STREAM(s, SHT_LOUSER   , kStrWidth);
3139     CASE_AND_STREAM(s, SHT_HIUSER   , kStrWidth);
3140     default:
3141         s->Printf("0x%8.8x%*s", sh_type, kStrWidth - 10, "");
3142         break;
3143     }
3144 }
3145 
3146 //----------------------------------------------------------------------
3147 // DumpELFSectionHeader_sh_flags
3148 //
3149 // Dump an token value for the ELF section header member sh_flags
3150 //----------------------------------------------------------------------
3151 void
3152 ObjectFileELF::DumpELFSectionHeader_sh_flags(Stream *s, elf_xword sh_flags)
3153 {
3154     *s  << ((sh_flags & SHF_WRITE) ? "WRITE" : "     ")
3155         << (((sh_flags & SHF_WRITE) && (sh_flags & SHF_ALLOC)) ? '+' : ' ')
3156         << ((sh_flags & SHF_ALLOC) ? "ALLOC" : "     ")
3157         << (((sh_flags & SHF_ALLOC) && (sh_flags & SHF_EXECINSTR)) ? '+' : ' ')
3158         << ((sh_flags & SHF_EXECINSTR) ? "EXECINSTR" : "         ");
3159 }
3160 
3161 //----------------------------------------------------------------------
3162 // DumpELFSectionHeaders
3163 //
3164 // Dump all of the ELF section header to the specified output stream
3165 //----------------------------------------------------------------------
3166 void
3167 ObjectFileELF::DumpELFSectionHeaders(Stream *s)
3168 {
3169     if (!ParseSectionHeaders())
3170         return;
3171 
3172     s->PutCString("Section Headers\n");
3173     s->PutCString("IDX  name     type         flags                            "
3174                   "addr     offset   size     link     info     addralgn "
3175                   "entsize  Name\n");
3176     s->PutCString("==== -------- ------------ -------------------------------- "
3177                   "-------- -------- -------- -------- -------- -------- "
3178                   "-------- ====================\n");
3179 
3180     uint32_t idx = 0;
3181     for (SectionHeaderCollConstIter I = m_section_headers.begin();
3182          I != m_section_headers.end(); ++I, ++idx)
3183     {
3184         s->Printf("[%2u] ", idx);
3185         ObjectFileELF::DumpELFSectionHeader(s, *I);
3186         const char* section_name = I->section_name.AsCString("");
3187         if (section_name)
3188             *s << ' ' << section_name << "\n";
3189     }
3190 }
3191 
3192 void
3193 ObjectFileELF::DumpDependentModules(lldb_private::Stream *s)
3194 {
3195     size_t num_modules = ParseDependentModules();
3196 
3197     if (num_modules > 0)
3198     {
3199         s->PutCString("Dependent Modules:\n");
3200         for (unsigned i = 0; i < num_modules; ++i)
3201         {
3202             const FileSpec &spec = m_filespec_ap->GetFileSpecAtIndex(i);
3203             s->Printf("   %s\n", spec.GetFilename().GetCString());
3204         }
3205     }
3206 }
3207 
3208 bool
3209 ObjectFileELF::GetArchitecture (ArchSpec &arch)
3210 {
3211     if (!ParseHeader())
3212         return false;
3213 
3214     if (m_section_headers.empty())
3215     {
3216         // Allow elf notes to be parsed which may affect the detected architecture.
3217         ParseSectionHeaders();
3218     }
3219 
3220     if (CalculateType() == eTypeCoreFile && m_arch_spec.TripleOSIsUnspecifiedUnknown())
3221     {
3222         // Core files don't have section headers yet they have PT_NOTE program headers
3223         // that might shed more light on the architecture
3224         if (ParseProgramHeaders())
3225         {
3226             for (size_t i = 0, count = GetProgramHeaderCount(); i < count; ++i)
3227             {
3228                 const elf::ELFProgramHeader* header = GetProgramHeaderByIndex(i);
3229                 if (header && header->p_type == PT_NOTE && header->p_offset != 0 && header->p_filesz > 0)
3230                 {
3231                     DataExtractor data;
3232                     if (data.SetData (m_data, header->p_offset, header->p_filesz) == header->p_filesz)
3233                     {
3234                         lldb_private::UUID uuid;
3235                         RefineModuleDetailsFromNote (data, m_arch_spec, uuid);
3236                     }
3237                 }
3238             }
3239         }
3240     }
3241     arch = m_arch_spec;
3242     return true;
3243 }
3244 
3245 ObjectFile::Type
3246 ObjectFileELF::CalculateType()
3247 {
3248     switch (m_header.e_type)
3249     {
3250         case llvm::ELF::ET_NONE:
3251             // 0 - No file type
3252             return eTypeUnknown;
3253 
3254         case llvm::ELF::ET_REL:
3255             // 1 - Relocatable file
3256             return eTypeObjectFile;
3257 
3258         case llvm::ELF::ET_EXEC:
3259             // 2 - Executable file
3260             return eTypeExecutable;
3261 
3262         case llvm::ELF::ET_DYN:
3263             // 3 - Shared object file
3264             return eTypeSharedLibrary;
3265 
3266         case ET_CORE:
3267             // 4 - Core file
3268             return eTypeCoreFile;
3269 
3270         default:
3271             break;
3272     }
3273     return eTypeUnknown;
3274 }
3275 
3276 ObjectFile::Strata
3277 ObjectFileELF::CalculateStrata()
3278 {
3279     switch (m_header.e_type)
3280     {
3281         case llvm::ELF::ET_NONE:
3282             // 0 - No file type
3283             return eStrataUnknown;
3284 
3285         case llvm::ELF::ET_REL:
3286             // 1 - Relocatable file
3287             return eStrataUnknown;
3288 
3289         case llvm::ELF::ET_EXEC:
3290             // 2 - Executable file
3291             // TODO: is there any way to detect that an executable is a kernel
3292             // related executable by inspecting the program headers, section
3293             // headers, symbols, or any other flag bits???
3294             return eStrataUser;
3295 
3296         case llvm::ELF::ET_DYN:
3297             // 3 - Shared object file
3298             // TODO: is there any way to detect that an shared library is a kernel
3299             // related executable by inspecting the program headers, section
3300             // headers, symbols, or any other flag bits???
3301             return eStrataUnknown;
3302 
3303         case ET_CORE:
3304             // 4 - Core file
3305             // TODO: is there any way to detect that an core file is a kernel
3306             // related executable by inspecting the program headers, section
3307             // headers, symbols, or any other flag bits???
3308             return eStrataUnknown;
3309 
3310         default:
3311             break;
3312     }
3313     return eStrataUnknown;
3314 }
3315 
3316