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::RoundUpToAlignment (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::RoundUpToAlignment (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 #if 0
1562         if (arch_spec.GetTriple().getOS() == llvm::Triple::OSType::UnknownOS)
1563             arch_spec.GetTriple().setOSName(HostInfo::GetOSString().data());
1564 #endif
1565         return 0;
1566     }
1567 
1568     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_MODULES));
1569 
1570     section_headers.resize(header.e_shnum);
1571     if (section_headers.size() != header.e_shnum)
1572         return 0;
1573 
1574     const size_t sh_size = header.e_shnum * header.e_shentsize;
1575     const elf_off sh_offset = header.e_shoff;
1576     DataExtractor sh_data;
1577     if (sh_data.SetData (object_data, sh_offset, sh_size) != sh_size)
1578         return 0;
1579 
1580     uint32_t idx;
1581     lldb::offset_t offset;
1582     for (idx = 0, offset = 0; idx < header.e_shnum; ++idx)
1583     {
1584         if (section_headers[idx].Parse(sh_data, &offset) == false)
1585             break;
1586     }
1587     if (idx < section_headers.size())
1588         section_headers.resize(idx);
1589 
1590     const unsigned strtab_idx = header.e_shstrndx;
1591     if (strtab_idx && strtab_idx < section_headers.size())
1592     {
1593         const ELFSectionHeaderInfo &sheader = section_headers[strtab_idx];
1594         const size_t byte_size = sheader.sh_size;
1595         const Elf64_Off offset = sheader.sh_offset;
1596         lldb_private::DataExtractor shstr_data;
1597 
1598         if (shstr_data.SetData (object_data, offset, byte_size) == byte_size)
1599         {
1600             for (SectionHeaderCollIter I = section_headers.begin();
1601                  I != section_headers.end(); ++I)
1602             {
1603                 static ConstString g_sect_name_gnu_debuglink (".gnu_debuglink");
1604                 const ELFSectionHeaderInfo &sheader = *I;
1605                 const uint64_t section_size = sheader.sh_type == SHT_NOBITS ? 0 : sheader.sh_size;
1606                 ConstString name(shstr_data.PeekCStr(I->sh_name));
1607 
1608                 I->section_name = name;
1609 
1610                 if (arch_spec.GetMachine() == llvm::Triple::mips || arch_spec.GetMachine() == llvm::Triple::mipsel
1611                     || arch_spec.GetMachine() == llvm::Triple::mips64 || arch_spec.GetMachine() == llvm::Triple::mips64el)
1612                 {
1613                     uint32_t arch_flags = arch_spec.GetFlags ();
1614                     DataExtractor data;
1615                     if (sheader.sh_type == SHT_MIPS_ABIFLAGS)
1616                     {
1617 
1618                         if (section_size && (data.SetData (object_data, sheader.sh_offset, section_size) == section_size))
1619                         {
1620                             lldb::offset_t ase_offset = 12; // MIPS ABI Flags Version: 0
1621                             arch_flags |= data.GetU32 (&ase_offset);
1622                         }
1623                     }
1624                     // Settings appropriate ArchSpec ABI Flags
1625                     if (header.e_flags & llvm::ELF::EF_MIPS_ABI2)
1626                     {
1627                         arch_flags |= lldb_private::ArchSpec::eMIPSABI_N32;
1628                     }
1629                     else if (header.e_flags & llvm::ELF::EF_MIPS_ABI_O32)
1630                     {
1631                          arch_flags |= lldb_private::ArchSpec::eMIPSABI_O32;
1632                     }
1633                     arch_spec.SetFlags (arch_flags);
1634                 }
1635 
1636                 if (name == g_sect_name_gnu_debuglink)
1637                 {
1638                     DataExtractor data;
1639                     if (section_size && (data.SetData (object_data, sheader.sh_offset, section_size) == section_size))
1640                     {
1641                         lldb::offset_t gnu_debuglink_offset = 0;
1642                         gnu_debuglink_file = data.GetCStr (&gnu_debuglink_offset);
1643                         gnu_debuglink_offset = llvm::RoundUpToAlignment (gnu_debuglink_offset, 4);
1644                         data.GetU32 (&gnu_debuglink_offset, &gnu_debuglink_crc, 1);
1645                     }
1646                 }
1647 
1648                 // Process ELF note section entries.
1649                 bool is_note_header = (sheader.sh_type == SHT_NOTE);
1650 
1651                 // The section header ".note.android.ident" is stored as a
1652                 // PROGBITS type header but it is actually a note header.
1653                 static ConstString g_sect_name_android_ident (".note.android.ident");
1654                 if (!is_note_header && name == g_sect_name_android_ident)
1655                     is_note_header = true;
1656 
1657                 if (is_note_header)
1658                 {
1659                     // Allow notes to refine module info.
1660                     DataExtractor data;
1661                     if (section_size && (data.SetData (object_data, sheader.sh_offset, section_size) == section_size))
1662                     {
1663                         Error error = RefineModuleDetailsFromNote (data, arch_spec, uuid);
1664                         if (error.Fail ())
1665                         {
1666                             if (log)
1667                                 log->Printf ("ObjectFileELF::%s ELF note processing failed: %s", __FUNCTION__, error.AsCString ());
1668                         }
1669                     }
1670                 }
1671             }
1672 
1673             // Make any unknown triple components to be unspecified unknowns.
1674             if (arch_spec.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
1675                 arch_spec.GetTriple().setVendorName (llvm::StringRef());
1676             if (arch_spec.GetTriple().getOS() == llvm::Triple::UnknownOS)
1677                 arch_spec.GetTriple().setOSName (llvm::StringRef());
1678 
1679             return section_headers.size();
1680         }
1681     }
1682 
1683     section_headers.clear();
1684     return 0;
1685 }
1686 
1687 size_t
1688 ObjectFileELF::GetProgramHeaderCount()
1689 {
1690     return ParseProgramHeaders();
1691 }
1692 
1693 const elf::ELFProgramHeader *
1694 ObjectFileELF::GetProgramHeaderByIndex(lldb::user_id_t id)
1695 {
1696     if (!id || !ParseProgramHeaders())
1697         return NULL;
1698 
1699     if (--id < m_program_headers.size())
1700         return &m_program_headers[id];
1701 
1702     return NULL;
1703 }
1704 
1705 DataExtractor
1706 ObjectFileELF::GetSegmentDataByIndex(lldb::user_id_t id)
1707 {
1708     const elf::ELFProgramHeader *segment_header = GetProgramHeaderByIndex(id);
1709     if (segment_header == NULL)
1710         return DataExtractor();
1711     return DataExtractor(m_data, segment_header->p_offset, segment_header->p_filesz);
1712 }
1713 
1714 std::string
1715 ObjectFileELF::StripLinkerSymbolAnnotations(llvm::StringRef symbol_name) const
1716 {
1717     size_t pos = symbol_name.find('@');
1718     return symbol_name.substr(0, pos).str();
1719 }
1720 
1721 //----------------------------------------------------------------------
1722 // ParseSectionHeaders
1723 //----------------------------------------------------------------------
1724 size_t
1725 ObjectFileELF::ParseSectionHeaders()
1726 {
1727     return GetSectionHeaderInfo(m_section_headers, m_data, m_header, m_uuid, m_gnu_debuglink_file, m_gnu_debuglink_crc, m_arch_spec);
1728 }
1729 
1730 const ObjectFileELF::ELFSectionHeaderInfo *
1731 ObjectFileELF::GetSectionHeaderByIndex(lldb::user_id_t id)
1732 {
1733     if (!id || !ParseSectionHeaders())
1734         return NULL;
1735 
1736     if (--id < m_section_headers.size())
1737         return &m_section_headers[id];
1738 
1739     return NULL;
1740 }
1741 
1742 lldb::user_id_t
1743 ObjectFileELF::GetSectionIndexByName(const char* name)
1744 {
1745     if (!name || !name[0] || !ParseSectionHeaders())
1746         return 0;
1747     for (size_t i = 1; i < m_section_headers.size(); ++i)
1748         if (m_section_headers[i].section_name == ConstString(name))
1749             return i;
1750     return 0;
1751 }
1752 
1753 void
1754 ObjectFileELF::CreateSections(SectionList &unified_section_list)
1755 {
1756     if (!m_sections_ap.get() && ParseSectionHeaders())
1757     {
1758         m_sections_ap.reset(new SectionList());
1759 
1760         for (SectionHeaderCollIter I = m_section_headers.begin();
1761              I != m_section_headers.end(); ++I)
1762         {
1763             const ELFSectionHeaderInfo &header = *I;
1764 
1765             ConstString& name = I->section_name;
1766             const uint64_t file_size = header.sh_type == SHT_NOBITS ? 0 : header.sh_size;
1767             const uint64_t vm_size = header.sh_flags & SHF_ALLOC ? header.sh_size : 0;
1768 
1769             static ConstString g_sect_name_text (".text");
1770             static ConstString g_sect_name_data (".data");
1771             static ConstString g_sect_name_bss (".bss");
1772             static ConstString g_sect_name_tdata (".tdata");
1773             static ConstString g_sect_name_tbss (".tbss");
1774             static ConstString g_sect_name_dwarf_debug_abbrev (".debug_abbrev");
1775             static ConstString g_sect_name_dwarf_debug_addr (".debug_addr");
1776             static ConstString g_sect_name_dwarf_debug_aranges (".debug_aranges");
1777             static ConstString g_sect_name_dwarf_debug_frame (".debug_frame");
1778             static ConstString g_sect_name_dwarf_debug_info (".debug_info");
1779             static ConstString g_sect_name_dwarf_debug_line (".debug_line");
1780             static ConstString g_sect_name_dwarf_debug_loc (".debug_loc");
1781             static ConstString g_sect_name_dwarf_debug_macinfo (".debug_macinfo");
1782             static ConstString g_sect_name_dwarf_debug_macro (".debug_macro");
1783             static ConstString g_sect_name_dwarf_debug_pubnames (".debug_pubnames");
1784             static ConstString g_sect_name_dwarf_debug_pubtypes (".debug_pubtypes");
1785             static ConstString g_sect_name_dwarf_debug_ranges (".debug_ranges");
1786             static ConstString g_sect_name_dwarf_debug_str (".debug_str");
1787             static ConstString g_sect_name_dwarf_debug_str_offsets (".debug_str_offsets");
1788             static ConstString g_sect_name_dwarf_debug_abbrev_dwo (".debug_abbrev.dwo");
1789             static ConstString g_sect_name_dwarf_debug_info_dwo (".debug_info.dwo");
1790             static ConstString g_sect_name_dwarf_debug_line_dwo (".debug_line.dwo");
1791             static ConstString g_sect_name_dwarf_debug_macro_dwo (".debug_macro.dwo");
1792             static ConstString g_sect_name_dwarf_debug_loc_dwo (".debug_loc.dwo");
1793             static ConstString g_sect_name_dwarf_debug_str_dwo (".debug_str.dwo");
1794             static ConstString g_sect_name_dwarf_debug_str_offsets_dwo (".debug_str_offsets.dwo");
1795             static ConstString g_sect_name_eh_frame (".eh_frame");
1796             static ConstString g_sect_name_arm_exidx (".ARM.exidx");
1797             static ConstString g_sect_name_arm_extab (".ARM.extab");
1798             static ConstString g_sect_name_go_symtab (".gosymtab");
1799 
1800             SectionType sect_type = eSectionTypeOther;
1801 
1802             bool is_thread_specific = false;
1803 
1804             if      (name == g_sect_name_text)                  sect_type = eSectionTypeCode;
1805             else if (name == g_sect_name_data)                  sect_type = eSectionTypeData;
1806             else if (name == g_sect_name_bss)                   sect_type = eSectionTypeZeroFill;
1807             else if (name == g_sect_name_tdata)
1808             {
1809                 sect_type = eSectionTypeData;
1810                 is_thread_specific = true;
1811             }
1812             else if (name == g_sect_name_tbss)
1813             {
1814                 sect_type = eSectionTypeZeroFill;
1815                 is_thread_specific = true;
1816             }
1817             // .debug_abbrev – Abbreviations used in the .debug_info section
1818             // .debug_aranges – Lookup table for mapping addresses to compilation units
1819             // .debug_frame – Call frame information
1820             // .debug_info – The core DWARF information section
1821             // .debug_line – Line number information
1822             // .debug_loc – Location lists used in DW_AT_location attributes
1823             // .debug_macinfo – Macro information
1824             // .debug_pubnames – Lookup table for mapping object and function names to compilation units
1825             // .debug_pubtypes – Lookup table for mapping type names to compilation units
1826             // .debug_ranges – Address ranges used in DW_AT_ranges attributes
1827             // .debug_str – String table used in .debug_info
1828             // MISSING? .gnu_debugdata - "mini debuginfo / MiniDebugInfo" section, http://sourceware.org/gdb/onlinedocs/gdb/MiniDebugInfo.html
1829             // MISSING? .debug-index - http://src.chromium.org/viewvc/chrome/trunk/src/build/gdb-add-index?pathrev=144644
1830             // MISSING? .debug_types - Type descriptions from DWARF 4? See http://gcc.gnu.org/wiki/DwarfSeparateTypeInfo
1831             else if (name == g_sect_name_dwarf_debug_abbrev)          sect_type = eSectionTypeDWARFDebugAbbrev;
1832             else if (name == g_sect_name_dwarf_debug_addr)            sect_type = eSectionTypeDWARFDebugAddr;
1833             else if (name == g_sect_name_dwarf_debug_aranges)         sect_type = eSectionTypeDWARFDebugAranges;
1834             else if (name == g_sect_name_dwarf_debug_frame)           sect_type = eSectionTypeDWARFDebugFrame;
1835             else if (name == g_sect_name_dwarf_debug_info)            sect_type = eSectionTypeDWARFDebugInfo;
1836             else if (name == g_sect_name_dwarf_debug_line)            sect_type = eSectionTypeDWARFDebugLine;
1837             else if (name == g_sect_name_dwarf_debug_loc)             sect_type = eSectionTypeDWARFDebugLoc;
1838             else if (name == g_sect_name_dwarf_debug_macinfo)         sect_type = eSectionTypeDWARFDebugMacInfo;
1839             else if (name == g_sect_name_dwarf_debug_macro)           sect_type = eSectionTypeDWARFDebugMacro;
1840             else if (name == g_sect_name_dwarf_debug_pubnames)        sect_type = eSectionTypeDWARFDebugPubNames;
1841             else if (name == g_sect_name_dwarf_debug_pubtypes)        sect_type = eSectionTypeDWARFDebugPubTypes;
1842             else if (name == g_sect_name_dwarf_debug_ranges)          sect_type = eSectionTypeDWARFDebugRanges;
1843             else if (name == g_sect_name_dwarf_debug_str)             sect_type = eSectionTypeDWARFDebugStr;
1844             else if (name == g_sect_name_dwarf_debug_str_offsets)     sect_type = eSectionTypeDWARFDebugStrOffsets;
1845             else if (name == g_sect_name_dwarf_debug_abbrev_dwo)      sect_type = eSectionTypeDWARFDebugAbbrev;
1846             else if (name == g_sect_name_dwarf_debug_info_dwo)        sect_type = eSectionTypeDWARFDebugInfo;
1847             else if (name == g_sect_name_dwarf_debug_line_dwo)        sect_type = eSectionTypeDWARFDebugLine;
1848             else if (name == g_sect_name_dwarf_debug_macro_dwo)       sect_type = eSectionTypeDWARFDebugMacro;
1849             else if (name == g_sect_name_dwarf_debug_loc_dwo)         sect_type = eSectionTypeDWARFDebugLoc;
1850             else if (name == g_sect_name_dwarf_debug_str_dwo)         sect_type = eSectionTypeDWARFDebugStr;
1851             else if (name == g_sect_name_dwarf_debug_str_offsets_dwo) sect_type = eSectionTypeDWARFDebugStrOffsets;
1852             else if (name == g_sect_name_eh_frame)                    sect_type = eSectionTypeEHFrame;
1853             else if (name == g_sect_name_arm_exidx)                   sect_type = eSectionTypeARMexidx;
1854             else if (name == g_sect_name_arm_extab)                   sect_type = eSectionTypeARMextab;
1855             else if (name == g_sect_name_go_symtab)                   sect_type = eSectionTypeGoSymtab;
1856 
1857             switch (header.sh_type)
1858             {
1859                 case SHT_SYMTAB:
1860                     assert (sect_type == eSectionTypeOther);
1861                     sect_type = eSectionTypeELFSymbolTable;
1862                     break;
1863                 case SHT_DYNSYM:
1864                     assert (sect_type == eSectionTypeOther);
1865                     sect_type = eSectionTypeELFDynamicSymbols;
1866                     break;
1867                 case SHT_RELA:
1868                 case SHT_REL:
1869                     assert (sect_type == eSectionTypeOther);
1870                     sect_type = eSectionTypeELFRelocationEntries;
1871                     break;
1872                 case SHT_DYNAMIC:
1873                     assert (sect_type == eSectionTypeOther);
1874                     sect_type = eSectionTypeELFDynamicLinkInfo;
1875                     break;
1876             }
1877 
1878             if (eSectionTypeOther == sect_type)
1879             {
1880                 // the kalimba toolchain assumes that ELF section names are free-form. It does
1881                 // support linkscripts which (can) give rise to various arbitrarily named
1882                 // sections being "Code" or "Data".
1883                 sect_type = kalimbaSectionType(m_header, header);
1884             }
1885 
1886             const uint32_t target_bytes_size =
1887                 (eSectionTypeData == sect_type || eSectionTypeZeroFill == sect_type) ?
1888                 m_arch_spec.GetDataByteSize() :
1889                     eSectionTypeCode == sect_type ?
1890                     m_arch_spec.GetCodeByteSize() : 1;
1891 
1892             elf::elf_xword log2align = (header.sh_addralign==0)
1893                                         ? 0
1894                                         : llvm::Log2_64(header.sh_addralign);
1895             SectionSP section_sp (new Section(GetModule(),        // Module to which this section belongs.
1896                                               this,               // ObjectFile to which this section belongs and should read section data from.
1897                                               SectionIndex(I),    // Section ID.
1898                                               name,               // Section name.
1899                                               sect_type,          // Section type.
1900                                               header.sh_addr,     // VM address.
1901                                               vm_size,            // VM size in bytes of this section.
1902                                               header.sh_offset,   // Offset of this section in the file.
1903                                               file_size,          // Size of the section as found in the file.
1904                                               log2align,          // Alignment of the section
1905                                               header.sh_flags,    // Flags for this section.
1906                                               target_bytes_size));// Number of host bytes per target byte
1907 
1908             if (is_thread_specific)
1909                 section_sp->SetIsThreadSpecific (is_thread_specific);
1910             m_sections_ap->AddSection(section_sp);
1911         }
1912     }
1913 
1914     if (m_sections_ap.get())
1915     {
1916         if (GetType() == eTypeDebugInfo)
1917         {
1918             static const SectionType g_sections[] =
1919             {
1920                 eSectionTypeDWARFDebugAbbrev,
1921                 eSectionTypeDWARFDebugAddr,
1922                 eSectionTypeDWARFDebugAranges,
1923                 eSectionTypeDWARFDebugFrame,
1924                 eSectionTypeDWARFDebugInfo,
1925                 eSectionTypeDWARFDebugLine,
1926                 eSectionTypeDWARFDebugLoc,
1927                 eSectionTypeDWARFDebugMacInfo,
1928                 eSectionTypeDWARFDebugPubNames,
1929                 eSectionTypeDWARFDebugPubTypes,
1930                 eSectionTypeDWARFDebugRanges,
1931                 eSectionTypeDWARFDebugStr,
1932                 eSectionTypeDWARFDebugStrOffsets,
1933                 eSectionTypeELFSymbolTable,
1934             };
1935             SectionList *elf_section_list = m_sections_ap.get();
1936             for (size_t idx = 0; idx < sizeof(g_sections) / sizeof(g_sections[0]); ++idx)
1937             {
1938                 SectionType section_type = g_sections[idx];
1939                 SectionSP section_sp (elf_section_list->FindSectionByType (section_type, true));
1940                 if (section_sp)
1941                 {
1942                     SectionSP module_section_sp (unified_section_list.FindSectionByType (section_type, true));
1943                     if (module_section_sp)
1944                         unified_section_list.ReplaceSection (module_section_sp->GetID(), section_sp);
1945                     else
1946                         unified_section_list.AddSection (section_sp);
1947                 }
1948             }
1949         }
1950         else
1951         {
1952             unified_section_list = *m_sections_ap;
1953         }
1954     }
1955 }
1956 
1957 // Find the arm/aarch64 mapping symbol character in the given symbol name. Mapping symbols have the
1958 // form of "$<char>[.<any>]*". Additionally we recognize cases when the mapping symbol prefixed by
1959 // an arbitrary string because if a symbol prefix added to each symbol in the object file with
1960 // objcopy then the mapping symbols are also prefixed.
1961 static char
1962 FindArmAarch64MappingSymbol(const char* symbol_name)
1963 {
1964     if (!symbol_name)
1965         return '\0';
1966 
1967     const char* dollar_pos = ::strchr(symbol_name, '$');
1968     if (!dollar_pos || dollar_pos[1] == '\0')
1969         return '\0';
1970 
1971     if (dollar_pos[2] == '\0' || dollar_pos[2] == '.')
1972         return dollar_pos[1];
1973     return '\0';
1974 }
1975 
1976 #define STO_MIPS_ISA            (3 << 6)
1977 #define STO_MICROMIPS           (2 << 6)
1978 #define IS_MICROMIPS(ST_OTHER)  (((ST_OTHER) & STO_MIPS_ISA) == STO_MICROMIPS)
1979 
1980 // private
1981 unsigned
1982 ObjectFileELF::ParseSymbols (Symtab *symtab,
1983                              user_id_t start_id,
1984                              SectionList *section_list,
1985                              const size_t num_symbols,
1986                              const DataExtractor &symtab_data,
1987                              const DataExtractor &strtab_data)
1988 {
1989     ELFSymbol symbol;
1990     lldb::offset_t offset = 0;
1991 
1992     static ConstString text_section_name(".text");
1993     static ConstString init_section_name(".init");
1994     static ConstString fini_section_name(".fini");
1995     static ConstString ctors_section_name(".ctors");
1996     static ConstString dtors_section_name(".dtors");
1997 
1998     static ConstString data_section_name(".data");
1999     static ConstString rodata_section_name(".rodata");
2000     static ConstString rodata1_section_name(".rodata1");
2001     static ConstString data2_section_name(".data1");
2002     static ConstString bss_section_name(".bss");
2003     static ConstString opd_section_name(".opd");    // For ppc64
2004 
2005     // On Android the oatdata and the oatexec symbols in system@[email protected] covers the full
2006     // .text section what causes issues with displaying unusable symbol name to the user and very
2007     // slow unwinding speed because the instruction emulation based unwind plans try to emulate all
2008     // instructions in these symbols. Don't add these symbols to the symbol list as they have no
2009     // use for the debugger and they are causing a lot of trouble.
2010     // Filtering can't be restricted to Android because this special object file don't contain the
2011     // note section specifying the environment to Android but the custom extension and file name
2012     // makes it highly unlikely that this will collide with anything else.
2013     bool skip_oatdata_oatexec = m_file.GetFilename() == ConstString("system@[email protected]");
2014 
2015     ArchSpec arch;
2016     GetArchitecture(arch);
2017 
2018     // Local cache to avoid doing a FindSectionByName for each symbol. The "const char*" key must
2019     // came from a ConstString object so they can be compared by pointer
2020     std::unordered_map<const char*, lldb::SectionSP> section_name_to_section;
2021 
2022     unsigned i;
2023     for (i = 0; i < num_symbols; ++i)
2024     {
2025         if (symbol.Parse(symtab_data, &offset) == false)
2026             break;
2027 
2028         const char *symbol_name = strtab_data.PeekCStr(symbol.st_name);
2029 
2030         // No need to add non-section symbols that have no names
2031         if (symbol.getType() != STT_SECTION &&
2032             (symbol_name == NULL || symbol_name[0] == '\0'))
2033             continue;
2034 
2035         // Skipping oatdata and oatexec sections if it is requested. See details above the
2036         // definition of skip_oatdata_oatexec for the reasons.
2037         if (skip_oatdata_oatexec && (::strcmp(symbol_name, "oatdata") == 0 || ::strcmp(symbol_name, "oatexec") == 0))
2038             continue;
2039 
2040         SectionSP symbol_section_sp;
2041         SymbolType symbol_type = eSymbolTypeInvalid;
2042         Elf64_Half symbol_idx = symbol.st_shndx;
2043 
2044         switch (symbol_idx)
2045         {
2046         case SHN_ABS:
2047             symbol_type = eSymbolTypeAbsolute;
2048             break;
2049         case SHN_UNDEF:
2050             symbol_type = eSymbolTypeUndefined;
2051             break;
2052         default:
2053             symbol_section_sp = section_list->GetSectionAtIndex(symbol_idx);
2054             break;
2055         }
2056 
2057         // If a symbol is undefined do not process it further even if it has a STT type
2058         if (symbol_type != eSymbolTypeUndefined)
2059         {
2060             switch (symbol.getType())
2061             {
2062             default:
2063             case STT_NOTYPE:
2064                 // The symbol's type is not specified.
2065                 break;
2066 
2067             case STT_OBJECT:
2068                 // The symbol is associated with a data object, such as a variable,
2069                 // an array, etc.
2070                 symbol_type = eSymbolTypeData;
2071                 break;
2072 
2073             case STT_FUNC:
2074                 // The symbol is associated with a function or other executable code.
2075                 symbol_type = eSymbolTypeCode;
2076                 break;
2077 
2078             case STT_SECTION:
2079                 // The symbol is associated with a section. Symbol table entries of
2080                 // this type exist primarily for relocation and normally have
2081                 // STB_LOCAL binding.
2082                 break;
2083 
2084             case STT_FILE:
2085                 // Conventionally, the symbol's name gives the name of the source
2086                 // file associated with the object file. A file symbol has STB_LOCAL
2087                 // binding, its section index is SHN_ABS, and it precedes the other
2088                 // STB_LOCAL symbols for the file, if it is present.
2089                 symbol_type = eSymbolTypeSourceFile;
2090                 break;
2091 
2092             case STT_GNU_IFUNC:
2093                 // The symbol is associated with an indirect function. The actual
2094                 // function will be resolved if it is referenced.
2095                 symbol_type = eSymbolTypeResolver;
2096                 break;
2097             }
2098         }
2099 
2100         if (symbol_type == eSymbolTypeInvalid)
2101         {
2102             if (symbol_section_sp)
2103             {
2104                 const ConstString &sect_name = symbol_section_sp->GetName();
2105                 if (sect_name == text_section_name ||
2106                     sect_name == init_section_name ||
2107                     sect_name == fini_section_name ||
2108                     sect_name == ctors_section_name ||
2109                     sect_name == dtors_section_name)
2110                 {
2111                     symbol_type = eSymbolTypeCode;
2112                 }
2113                 else if (sect_name == data_section_name ||
2114                          sect_name == data2_section_name ||
2115                          sect_name == rodata_section_name ||
2116                          sect_name == rodata1_section_name ||
2117                          sect_name == bss_section_name)
2118                 {
2119                     symbol_type = eSymbolTypeData;
2120                 }
2121             }
2122         }
2123 
2124         int64_t symbol_value_offset = 0;
2125         uint32_t additional_flags = 0;
2126 
2127         if (arch.IsValid())
2128         {
2129             if (arch.GetMachine() == llvm::Triple::arm)
2130             {
2131                 if (symbol.getBinding() == STB_LOCAL)
2132                 {
2133                     char mapping_symbol = FindArmAarch64MappingSymbol(symbol_name);
2134                     if (symbol_type == eSymbolTypeCode)
2135                     {
2136                         switch (mapping_symbol)
2137                         {
2138                             case 'a':
2139                                 // $a[.<any>]* - marks an ARM instruction sequence
2140                                 m_address_class_map[symbol.st_value] = eAddressClassCode;
2141                                 break;
2142                             case 'b':
2143                             case 't':
2144                                 // $b[.<any>]* - marks a THUMB BL instruction sequence
2145                                 // $t[.<any>]* - marks a THUMB instruction sequence
2146                                 m_address_class_map[symbol.st_value] = eAddressClassCodeAlternateISA;
2147                                 break;
2148                             case 'd':
2149                                 // $d[.<any>]* - marks a data item sequence (e.g. lit pool)
2150                                 m_address_class_map[symbol.st_value] = eAddressClassData;
2151                                 break;
2152                         }
2153                     }
2154                     if (mapping_symbol)
2155                         continue;
2156                 }
2157             }
2158             else if (arch.GetMachine() == llvm::Triple::aarch64)
2159             {
2160                 if (symbol.getBinding() == STB_LOCAL)
2161                 {
2162                     char mapping_symbol = FindArmAarch64MappingSymbol(symbol_name);
2163                     if (symbol_type == eSymbolTypeCode)
2164                     {
2165                         switch (mapping_symbol)
2166                         {
2167                             case 'x':
2168                                 // $x[.<any>]* - marks an A64 instruction sequence
2169                                 m_address_class_map[symbol.st_value] = eAddressClassCode;
2170                                 break;
2171                             case 'd':
2172                                 // $d[.<any>]* - marks a data item sequence (e.g. lit pool)
2173                                 m_address_class_map[symbol.st_value] = eAddressClassData;
2174                                 break;
2175                         }
2176                     }
2177                     if (mapping_symbol)
2178                         continue;
2179                 }
2180             }
2181 
2182             if (arch.GetMachine() == llvm::Triple::arm)
2183             {
2184                 if (symbol_type == eSymbolTypeCode)
2185                 {
2186                     if (symbol.st_value & 1)
2187                     {
2188                         // Subtracting 1 from the address effectively unsets
2189                         // the low order bit, which results in the address
2190                         // actually pointing to the beginning of the symbol.
2191                         // This delta will be used below in conjunction with
2192                         // symbol.st_value to produce the final symbol_value
2193                         // that we store in the symtab.
2194                         symbol_value_offset = -1;
2195                         m_address_class_map[symbol.st_value^1] = eAddressClassCodeAlternateISA;
2196                     }
2197                     else
2198                     {
2199                         // This address is ARM
2200                         m_address_class_map[symbol.st_value] = eAddressClassCode;
2201                     }
2202                 }
2203             }
2204 
2205             /*
2206              * MIPS:
2207              * The bit #0 of an address is used for ISA mode (1 for microMIPS, 0 for MIPS).
2208              * This allows processer to switch between microMIPS and MIPS without any need
2209              * for special mode-control register. However, apart from .debug_line, none of
2210              * the ELF/DWARF sections set the ISA bit (for symbol or section). Use st_other
2211              * flag to check whether the symbol is microMIPS and then set the address class
2212              * accordingly.
2213             */
2214             const llvm::Triple::ArchType llvm_arch = arch.GetMachine();
2215             if (llvm_arch == llvm::Triple::mips || llvm_arch == llvm::Triple::mipsel
2216                 || llvm_arch == llvm::Triple::mips64 || llvm_arch == llvm::Triple::mips64el)
2217             {
2218                 if (IS_MICROMIPS(symbol.st_other))
2219                     m_address_class_map[symbol.st_value] = eAddressClassCodeAlternateISA;
2220                 else if ((symbol.st_value & 1) && (symbol_type == eSymbolTypeCode))
2221                 {
2222                     symbol.st_value = symbol.st_value & (~1ull);
2223                     m_address_class_map[symbol.st_value] = eAddressClassCodeAlternateISA;
2224                 }
2225                 else
2226                 {
2227                     if (symbol_type == eSymbolTypeCode)
2228                         m_address_class_map[symbol.st_value] = eAddressClassCode;
2229                     else if (symbol_type == eSymbolTypeData)
2230                         m_address_class_map[symbol.st_value] = eAddressClassData;
2231                     else
2232                         m_address_class_map[symbol.st_value] = eAddressClassUnknown;
2233                 }
2234             }
2235         }
2236 
2237         // symbol_value_offset may contain 0 for ARM symbols or -1 for
2238         // THUMB symbols. See above for more details.
2239         uint64_t symbol_value = symbol.st_value + symbol_value_offset;
2240         if (symbol_section_sp && CalculateType() != ObjectFile::Type::eTypeObjectFile)
2241             symbol_value -= symbol_section_sp->GetFileAddress();
2242 
2243         if (symbol_section_sp)
2244         {
2245             ModuleSP module_sp(GetModule());
2246             if (module_sp)
2247             {
2248                 SectionList *module_section_list = module_sp->GetSectionList();
2249                 if (module_section_list && module_section_list != section_list)
2250                 {
2251                     const ConstString &sect_name = symbol_section_sp->GetName();
2252                     auto section_it = section_name_to_section.find(sect_name.GetCString());
2253                     if (section_it == section_name_to_section.end())
2254                         section_it = section_name_to_section.emplace(
2255                             sect_name.GetCString(),
2256                             module_section_list->FindSectionByName (sect_name)).first;
2257                     if (section_it->second && section_it->second->GetFileSize())
2258                         symbol_section_sp = section_it->second;
2259                 }
2260             }
2261         }
2262 
2263         bool is_global = symbol.getBinding() == STB_GLOBAL;
2264         uint32_t flags = symbol.st_other << 8 | symbol.st_info | additional_flags;
2265         bool is_mangled = symbol_name ? (symbol_name[0] == '_' && symbol_name[1] == 'Z') : false;
2266 
2267         llvm::StringRef symbol_ref(symbol_name);
2268 
2269         // Symbol names may contain @VERSION suffixes. Find those and strip them temporarily.
2270         size_t version_pos = symbol_ref.find('@');
2271         bool has_suffix = version_pos != llvm::StringRef::npos;
2272         llvm::StringRef symbol_bare = symbol_ref.substr(0, version_pos);
2273         Mangled mangled(ConstString(symbol_bare), is_mangled);
2274 
2275         // Now append the suffix back to mangled and unmangled names. Only do it if the
2276         // demangling was successful (string is not empty).
2277         if (has_suffix)
2278         {
2279             llvm::StringRef suffix = symbol_ref.substr(version_pos);
2280 
2281             llvm::StringRef mangled_name = mangled.GetMangledName().GetStringRef();
2282             if (! mangled_name.empty())
2283                 mangled.SetMangledName( ConstString((mangled_name + suffix).str()) );
2284 
2285             ConstString demangled = mangled.GetDemangledName(lldb::eLanguageTypeUnknown);
2286             llvm::StringRef demangled_name = demangled.GetStringRef();
2287             if (!demangled_name.empty())
2288                 mangled.SetDemangledName( ConstString((demangled_name + suffix).str()) );
2289         }
2290 
2291         Symbol dc_symbol(
2292             i + start_id,       // ID is the original symbol table index.
2293             mangled,
2294             symbol_type,        // Type of this symbol
2295             is_global,          // Is this globally visible?
2296             false,              // Is this symbol debug info?
2297             false,              // Is this symbol a trampoline?
2298             false,              // Is this symbol artificial?
2299             AddressRange(
2300                 symbol_section_sp,  // Section in which this symbol is defined or null.
2301                 symbol_value,       // Offset in section or symbol value.
2302                 symbol.st_size),    // Size in bytes of this symbol.
2303             symbol.st_size != 0,    // Size is valid if it is not 0
2304             has_suffix,             // Contains linker annotations?
2305             flags);                 // Symbol flags.
2306         symtab->AddSymbol(dc_symbol);
2307     }
2308     return i;
2309 }
2310 
2311 unsigned
2312 ObjectFileELF::ParseSymbolTable(Symtab *symbol_table, user_id_t start_id, lldb_private::Section *symtab)
2313 {
2314     if (symtab->GetObjectFile() != this)
2315     {
2316         // If the symbol table section is owned by a different object file, have it do the
2317         // parsing.
2318         ObjectFileELF *obj_file_elf = static_cast<ObjectFileELF *>(symtab->GetObjectFile());
2319         return obj_file_elf->ParseSymbolTable (symbol_table, start_id, symtab);
2320     }
2321 
2322     // Get section list for this object file.
2323     SectionList *section_list = m_sections_ap.get();
2324     if (!section_list)
2325         return 0;
2326 
2327     user_id_t symtab_id = symtab->GetID();
2328     const ELFSectionHeaderInfo *symtab_hdr = GetSectionHeaderByIndex(symtab_id);
2329     assert(symtab_hdr->sh_type == SHT_SYMTAB ||
2330            symtab_hdr->sh_type == SHT_DYNSYM);
2331 
2332     // sh_link: section header index of associated string table.
2333     // Section ID's are ones based.
2334     user_id_t strtab_id = symtab_hdr->sh_link + 1;
2335     Section *strtab = section_list->FindSectionByID(strtab_id).get();
2336 
2337     if (symtab && strtab)
2338     {
2339         assert (symtab->GetObjectFile() == this);
2340         assert (strtab->GetObjectFile() == this);
2341 
2342         DataExtractor symtab_data;
2343         DataExtractor strtab_data;
2344         if (ReadSectionData(symtab, symtab_data) &&
2345             ReadSectionData(strtab, strtab_data))
2346         {
2347             size_t num_symbols = symtab_data.GetByteSize() / symtab_hdr->sh_entsize;
2348 
2349             return ParseSymbols(symbol_table, start_id, section_list,
2350                                 num_symbols, symtab_data, strtab_data);
2351         }
2352     }
2353 
2354     return 0;
2355 }
2356 
2357 size_t
2358 ObjectFileELF::ParseDynamicSymbols()
2359 {
2360     if (m_dynamic_symbols.size())
2361         return m_dynamic_symbols.size();
2362 
2363     SectionList *section_list = GetSectionList();
2364     if (!section_list)
2365         return 0;
2366 
2367     // Find the SHT_DYNAMIC section.
2368     Section *dynsym = section_list->FindSectionByType (eSectionTypeELFDynamicLinkInfo, true).get();
2369     if (!dynsym)
2370         return 0;
2371     assert (dynsym->GetObjectFile() == this);
2372 
2373     ELFDynamic symbol;
2374     DataExtractor dynsym_data;
2375     if (ReadSectionData(dynsym, dynsym_data))
2376     {
2377         const lldb::offset_t section_size = dynsym_data.GetByteSize();
2378         lldb::offset_t cursor = 0;
2379 
2380         while (cursor < section_size)
2381         {
2382             if (!symbol.Parse(dynsym_data, &cursor))
2383                 break;
2384 
2385             m_dynamic_symbols.push_back(symbol);
2386         }
2387     }
2388 
2389     return m_dynamic_symbols.size();
2390 }
2391 
2392 const ELFDynamic *
2393 ObjectFileELF::FindDynamicSymbol(unsigned tag)
2394 {
2395     if (!ParseDynamicSymbols())
2396         return NULL;
2397 
2398     DynamicSymbolCollIter I = m_dynamic_symbols.begin();
2399     DynamicSymbolCollIter E = m_dynamic_symbols.end();
2400     for ( ; I != E; ++I)
2401     {
2402         ELFDynamic *symbol = &*I;
2403 
2404         if (symbol->d_tag == tag)
2405             return symbol;
2406     }
2407 
2408     return NULL;
2409 }
2410 
2411 unsigned
2412 ObjectFileELF::PLTRelocationType()
2413 {
2414     // DT_PLTREL
2415     //  This member specifies the type of relocation entry to which the
2416     //  procedure linkage table refers. The d_val member holds DT_REL or
2417     //  DT_RELA, as appropriate. All relocations in a procedure linkage table
2418     //  must use the same relocation.
2419     const ELFDynamic *symbol = FindDynamicSymbol(DT_PLTREL);
2420 
2421     if (symbol)
2422         return symbol->d_val;
2423 
2424     return 0;
2425 }
2426 
2427 // Returns the size of the normal plt entries and the offset of the first normal plt entry. The
2428 // 0th entry in the plt table is usually a resolution entry which have different size in some
2429 // architectures then the rest of the plt entries.
2430 static std::pair<uint64_t, uint64_t>
2431 GetPltEntrySizeAndOffset(const ELFSectionHeader* rel_hdr, const ELFSectionHeader* plt_hdr)
2432 {
2433     const elf_xword num_relocations = rel_hdr->sh_size / rel_hdr->sh_entsize;
2434 
2435     // Clang 3.3 sets entsize to 4 for 32-bit binaries, but the plt entries are 16 bytes.
2436     // So round the entsize up by the alignment if addralign is set.
2437     elf_xword plt_entsize = plt_hdr->sh_addralign ?
2438         llvm::RoundUpToAlignment (plt_hdr->sh_entsize, plt_hdr->sh_addralign) : plt_hdr->sh_entsize;
2439 
2440     if (plt_entsize == 0)
2441     {
2442         // The linker haven't set the plt_hdr->sh_entsize field. Try to guess the size of the plt
2443         // entries based on the number of entries and the size of the plt section with the
2444         // assumption that the size of the 0th entry is at least as big as the size of the normal
2445         // entries and it isn't much bigger then that.
2446         if (plt_hdr->sh_addralign)
2447             plt_entsize = plt_hdr->sh_size / plt_hdr->sh_addralign / (num_relocations + 1) * plt_hdr->sh_addralign;
2448         else
2449             plt_entsize = plt_hdr->sh_size / (num_relocations + 1);
2450     }
2451 
2452     elf_xword plt_offset = plt_hdr->sh_size - num_relocations * plt_entsize;
2453 
2454     return std::make_pair(plt_entsize, plt_offset);
2455 }
2456 
2457 static unsigned
2458 ParsePLTRelocations(Symtab *symbol_table,
2459                     user_id_t start_id,
2460                     unsigned rel_type,
2461                     const ELFHeader *hdr,
2462                     const ELFSectionHeader *rel_hdr,
2463                     const ELFSectionHeader *plt_hdr,
2464                     const ELFSectionHeader *sym_hdr,
2465                     const lldb::SectionSP &plt_section_sp,
2466                     DataExtractor &rel_data,
2467                     DataExtractor &symtab_data,
2468                     DataExtractor &strtab_data)
2469 {
2470     ELFRelocation rel(rel_type);
2471     ELFSymbol symbol;
2472     lldb::offset_t offset = 0;
2473 
2474     uint64_t plt_offset, plt_entsize;
2475     std::tie(plt_entsize, plt_offset) = GetPltEntrySizeAndOffset(rel_hdr, plt_hdr);
2476     const elf_xword num_relocations = rel_hdr->sh_size / rel_hdr->sh_entsize;
2477 
2478     typedef unsigned (*reloc_info_fn)(const ELFRelocation &rel);
2479     reloc_info_fn reloc_type;
2480     reloc_info_fn reloc_symbol;
2481 
2482     if (hdr->Is32Bit())
2483     {
2484         reloc_type = ELFRelocation::RelocType32;
2485         reloc_symbol = ELFRelocation::RelocSymbol32;
2486     }
2487     else
2488     {
2489         reloc_type = ELFRelocation::RelocType64;
2490         reloc_symbol = ELFRelocation::RelocSymbol64;
2491     }
2492 
2493     unsigned slot_type = hdr->GetRelocationJumpSlotType();
2494     unsigned i;
2495     for (i = 0; i < num_relocations; ++i)
2496     {
2497         if (rel.Parse(rel_data, &offset) == false)
2498             break;
2499 
2500         if (reloc_type(rel) != slot_type)
2501             continue;
2502 
2503         lldb::offset_t symbol_offset = reloc_symbol(rel) * sym_hdr->sh_entsize;
2504         if (!symbol.Parse(symtab_data, &symbol_offset))
2505             break;
2506 
2507         const char *symbol_name = strtab_data.PeekCStr(symbol.st_name);
2508         bool is_mangled = symbol_name ? (symbol_name[0] == '_' && symbol_name[1] == 'Z') : false;
2509         uint64_t plt_index = plt_offset + i * plt_entsize;
2510 
2511         Symbol jump_symbol(
2512             i + start_id,    // Symbol table index
2513             symbol_name,     // symbol name.
2514             is_mangled,      // is the symbol name mangled?
2515             eSymbolTypeTrampoline, // Type of this symbol
2516             false,           // Is this globally visible?
2517             false,           // Is this symbol debug info?
2518             true,            // Is this symbol a trampoline?
2519             true,            // Is this symbol artificial?
2520             plt_section_sp,  // Section in which this symbol is defined or null.
2521             plt_index,       // Offset in section or symbol value.
2522             plt_entsize,     // Size in bytes of this symbol.
2523             true,            // Size is valid
2524             false,           // Contains linker annotations?
2525             0);              // Symbol flags.
2526 
2527         symbol_table->AddSymbol(jump_symbol);
2528     }
2529 
2530     return i;
2531 }
2532 
2533 unsigned
2534 ObjectFileELF::ParseTrampolineSymbols(Symtab *symbol_table,
2535                                       user_id_t start_id,
2536                                       const ELFSectionHeaderInfo *rel_hdr,
2537                                       user_id_t rel_id)
2538 {
2539     assert(rel_hdr->sh_type == SHT_RELA || rel_hdr->sh_type == SHT_REL);
2540 
2541     // The link field points to the associated symbol table. The info field
2542     // points to the section holding the plt.
2543     user_id_t symtab_id = rel_hdr->sh_link;
2544     user_id_t plt_id = rel_hdr->sh_info;
2545 
2546     // If the link field doesn't point to the appropriate symbol name table then
2547     // try to find it by name as some compiler don't fill in the link fields.
2548     if (!symtab_id)
2549         symtab_id = GetSectionIndexByName(".dynsym");
2550     if (!plt_id)
2551         plt_id = GetSectionIndexByName(".plt");
2552 
2553     if (!symtab_id || !plt_id)
2554         return 0;
2555 
2556     // Section ID's are ones based;
2557     symtab_id++;
2558     plt_id++;
2559 
2560     const ELFSectionHeaderInfo *plt_hdr = GetSectionHeaderByIndex(plt_id);
2561     if (!plt_hdr)
2562         return 0;
2563 
2564     const ELFSectionHeaderInfo *sym_hdr = GetSectionHeaderByIndex(symtab_id);
2565     if (!sym_hdr)
2566         return 0;
2567 
2568     SectionList *section_list = m_sections_ap.get();
2569     if (!section_list)
2570         return 0;
2571 
2572     Section *rel_section = section_list->FindSectionByID(rel_id).get();
2573     if (!rel_section)
2574         return 0;
2575 
2576     SectionSP plt_section_sp (section_list->FindSectionByID(plt_id));
2577     if (!plt_section_sp)
2578         return 0;
2579 
2580     Section *symtab = section_list->FindSectionByID(symtab_id).get();
2581     if (!symtab)
2582         return 0;
2583 
2584     // sh_link points to associated string table.
2585     Section *strtab = section_list->FindSectionByID(sym_hdr->sh_link + 1).get();
2586     if (!strtab)
2587         return 0;
2588 
2589     DataExtractor rel_data;
2590     if (!ReadSectionData(rel_section, rel_data))
2591         return 0;
2592 
2593     DataExtractor symtab_data;
2594     if (!ReadSectionData(symtab, symtab_data))
2595         return 0;
2596 
2597     DataExtractor strtab_data;
2598     if (!ReadSectionData(strtab, strtab_data))
2599         return 0;
2600 
2601     unsigned rel_type = PLTRelocationType();
2602     if (!rel_type)
2603         return 0;
2604 
2605     return ParsePLTRelocations (symbol_table,
2606                                 start_id,
2607                                 rel_type,
2608                                 &m_header,
2609                                 rel_hdr,
2610                                 plt_hdr,
2611                                 sym_hdr,
2612                                 plt_section_sp,
2613                                 rel_data,
2614                                 symtab_data,
2615                                 strtab_data);
2616 }
2617 
2618 unsigned
2619 ObjectFileELF::RelocateSection(Symtab* symtab, const ELFHeader *hdr, const ELFSectionHeader *rel_hdr,
2620                 const ELFSectionHeader *symtab_hdr, const ELFSectionHeader *debug_hdr,
2621                 DataExtractor &rel_data, DataExtractor &symtab_data,
2622                 DataExtractor &debug_data, Section* rel_section)
2623 {
2624     ELFRelocation rel(rel_hdr->sh_type);
2625     lldb::addr_t offset = 0;
2626     const unsigned num_relocations = rel_hdr->sh_size / rel_hdr->sh_entsize;
2627     typedef unsigned (*reloc_info_fn)(const ELFRelocation &rel);
2628     reloc_info_fn reloc_type;
2629     reloc_info_fn reloc_symbol;
2630 
2631     if (hdr->Is32Bit())
2632     {
2633         reloc_type = ELFRelocation::RelocType32;
2634         reloc_symbol = ELFRelocation::RelocSymbol32;
2635     }
2636     else
2637     {
2638         reloc_type = ELFRelocation::RelocType64;
2639         reloc_symbol = ELFRelocation::RelocSymbol64;
2640     }
2641 
2642     for (unsigned i = 0; i < num_relocations; ++i)
2643     {
2644         if (rel.Parse(rel_data, &offset) == false)
2645             break;
2646 
2647         Symbol* symbol = NULL;
2648 
2649         if (hdr->Is32Bit())
2650         {
2651             switch (reloc_type(rel)) {
2652             case R_386_32:
2653             case R_386_PC32:
2654             default:
2655                 assert(false && "unexpected relocation type");
2656             }
2657         } else {
2658             switch (reloc_type(rel)) {
2659             case R_X86_64_64:
2660             {
2661                 symbol = symtab->FindSymbolByID(reloc_symbol(rel));
2662                 if (symbol)
2663                 {
2664                     addr_t value = symbol->GetAddressRef().GetFileAddress();
2665                     DataBufferSP& data_buffer_sp = debug_data.GetSharedDataBuffer();
2666                     uint64_t* dst = reinterpret_cast<uint64_t*>(data_buffer_sp->GetBytes() + rel_section->GetFileOffset() + ELFRelocation::RelocOffset64(rel));
2667                     *dst = value + ELFRelocation::RelocAddend64(rel);
2668                 }
2669                 break;
2670             }
2671             case R_X86_64_32:
2672             case R_X86_64_32S:
2673             {
2674                 symbol = symtab->FindSymbolByID(reloc_symbol(rel));
2675                 if (symbol)
2676                 {
2677                     addr_t value = symbol->GetAddressRef().GetFileAddress();
2678                     value += ELFRelocation::RelocAddend32(rel);
2679                     assert((reloc_type(rel) == R_X86_64_32 && (value <= UINT32_MAX)) ||
2680                            (reloc_type(rel) == R_X86_64_32S &&
2681                             ((int64_t)value <= INT32_MAX && (int64_t)value >= INT32_MIN)));
2682                     uint32_t truncated_addr = (value & 0xFFFFFFFF);
2683                     DataBufferSP& data_buffer_sp = debug_data.GetSharedDataBuffer();
2684                     uint32_t* dst = reinterpret_cast<uint32_t*>(data_buffer_sp->GetBytes() + rel_section->GetFileOffset() + ELFRelocation::RelocOffset32(rel));
2685                     *dst = truncated_addr;
2686                 }
2687                 break;
2688             }
2689             case R_X86_64_PC32:
2690             default:
2691                 assert(false && "unexpected relocation type");
2692             }
2693         }
2694     }
2695 
2696     return 0;
2697 }
2698 
2699 unsigned
2700 ObjectFileELF::RelocateDebugSections(const ELFSectionHeader *rel_hdr, user_id_t rel_id)
2701 {
2702     assert(rel_hdr->sh_type == SHT_RELA || rel_hdr->sh_type == SHT_REL);
2703 
2704     // Parse in the section list if needed.
2705     SectionList *section_list = GetSectionList();
2706     if (!section_list)
2707         return 0;
2708 
2709     // Section ID's are ones based.
2710     user_id_t symtab_id = rel_hdr->sh_link + 1;
2711     user_id_t debug_id = rel_hdr->sh_info + 1;
2712 
2713     const ELFSectionHeader *symtab_hdr = GetSectionHeaderByIndex(symtab_id);
2714     if (!symtab_hdr)
2715         return 0;
2716 
2717     const ELFSectionHeader *debug_hdr = GetSectionHeaderByIndex(debug_id);
2718     if (!debug_hdr)
2719         return 0;
2720 
2721     Section *rel = section_list->FindSectionByID(rel_id).get();
2722     if (!rel)
2723         return 0;
2724 
2725     Section *symtab = section_list->FindSectionByID(symtab_id).get();
2726     if (!symtab)
2727         return 0;
2728 
2729     Section *debug = section_list->FindSectionByID(debug_id).get();
2730     if (!debug)
2731         return 0;
2732 
2733     DataExtractor rel_data;
2734     DataExtractor symtab_data;
2735     DataExtractor debug_data;
2736 
2737     if (ReadSectionData(rel, rel_data) &&
2738         ReadSectionData(symtab, symtab_data) &&
2739         ReadSectionData(debug, debug_data))
2740     {
2741         RelocateSection(m_symtab_ap.get(), &m_header, rel_hdr, symtab_hdr, debug_hdr,
2742                         rel_data, symtab_data, debug_data, debug);
2743     }
2744 
2745     return 0;
2746 }
2747 
2748 Symtab *
2749 ObjectFileELF::GetSymtab()
2750 {
2751     ModuleSP module_sp(GetModule());
2752     if (!module_sp)
2753         return NULL;
2754 
2755     // We always want to use the main object file so we (hopefully) only have one cached copy
2756     // of our symtab, dynamic sections, etc.
2757     ObjectFile *module_obj_file = module_sp->GetObjectFile();
2758     if (module_obj_file && module_obj_file != this)
2759         return module_obj_file->GetSymtab();
2760 
2761     if (m_symtab_ap.get() == NULL)
2762     {
2763         SectionList *section_list = module_sp->GetSectionList();
2764         if (!section_list)
2765             return NULL;
2766 
2767         uint64_t symbol_id = 0;
2768         lldb_private::Mutex::Locker locker(module_sp->GetMutex());
2769 
2770         // Sharable objects and dynamic executables usually have 2 distinct symbol
2771         // tables, one named ".symtab", and the other ".dynsym". The dynsym is a smaller
2772         // version of the symtab that only contains global symbols. The information found
2773         // in the dynsym is therefore also found in the symtab, while the reverse is not
2774         // necessarily true.
2775         Section *symtab = section_list->FindSectionByType (eSectionTypeELFSymbolTable, true).get();
2776         if (!symtab)
2777         {
2778             // The symtab section is non-allocable and can be stripped, so if it doesn't exist
2779             // then use the dynsym section which should always be there.
2780             symtab = section_list->FindSectionByType (eSectionTypeELFDynamicSymbols, true).get();
2781         }
2782         if (symtab)
2783         {
2784             m_symtab_ap.reset(new Symtab(symtab->GetObjectFile()));
2785             symbol_id += ParseSymbolTable (m_symtab_ap.get(), symbol_id, symtab);
2786         }
2787 
2788         // DT_JMPREL
2789         //      If present, this entry's d_ptr member holds the address of relocation
2790         //      entries associated solely with the procedure linkage table. Separating
2791         //      these relocation entries lets the dynamic linker ignore them during
2792         //      process initialization, if lazy binding is enabled. If this entry is
2793         //      present, the related entries of types DT_PLTRELSZ and DT_PLTREL must
2794         //      also be present.
2795         const ELFDynamic *symbol = FindDynamicSymbol(DT_JMPREL);
2796         if (symbol)
2797         {
2798             // Synthesize trampoline symbols to help navigate the PLT.
2799             addr_t addr = symbol->d_ptr;
2800             Section *reloc_section = section_list->FindSectionContainingFileAddress(addr).get();
2801             if (reloc_section)
2802             {
2803                 user_id_t reloc_id = reloc_section->GetID();
2804                 const ELFSectionHeaderInfo *reloc_header = GetSectionHeaderByIndex(reloc_id);
2805                 assert(reloc_header);
2806 
2807                 if (m_symtab_ap == nullptr)
2808                     m_symtab_ap.reset(new Symtab(reloc_section->GetObjectFile()));
2809 
2810                 ParseTrampolineSymbols (m_symtab_ap.get(), symbol_id, reloc_header, reloc_id);
2811             }
2812         }
2813 
2814         // If we still don't have any symtab then create an empty instance to avoid do the section
2815         // lookup next time.
2816         if (m_symtab_ap == nullptr)
2817             m_symtab_ap.reset(new Symtab(this));
2818 
2819         m_symtab_ap->CalculateSymbolSizes();
2820     }
2821 
2822     for (SectionHeaderCollIter I = m_section_headers.begin();
2823          I != m_section_headers.end(); ++I)
2824     {
2825         if (I->sh_type == SHT_RELA || I->sh_type == SHT_REL)
2826         {
2827             if (CalculateType() == eTypeObjectFile)
2828             {
2829                 const char *section_name = I->section_name.AsCString("");
2830                 if (strstr(section_name, ".rela.debug") ||
2831                     strstr(section_name, ".rel.debug"))
2832                 {
2833                     const ELFSectionHeader &reloc_header = *I;
2834                     user_id_t reloc_id = SectionIndex(I);
2835                     RelocateDebugSections(&reloc_header, reloc_id);
2836                 }
2837             }
2838         }
2839     }
2840     return m_symtab_ap.get();
2841 }
2842 
2843 Symbol *
2844 ObjectFileELF::ResolveSymbolForAddress(const Address& so_addr, bool verify_unique)
2845 {
2846     if (!m_symtab_ap.get())
2847         return nullptr; // GetSymtab() should be called first.
2848 
2849     const SectionList *section_list = GetSectionList();
2850     if (!section_list)
2851         return nullptr;
2852 
2853     if (DWARFCallFrameInfo *eh_frame = GetUnwindTable().GetEHFrameInfo())
2854     {
2855         AddressRange range;
2856         if (eh_frame->GetAddressRange (so_addr, range))
2857         {
2858             const addr_t file_addr = range.GetBaseAddress().GetFileAddress();
2859             Symbol * symbol = verify_unique ? m_symtab_ap->FindSymbolContainingFileAddress(file_addr) : nullptr;
2860             if (symbol)
2861                 return symbol;
2862 
2863             // Note that a (stripped) symbol won't be found by GetSymtab()...
2864             lldb::SectionSP eh_sym_section_sp = section_list->FindSectionContainingFileAddress(file_addr);
2865             if (eh_sym_section_sp.get())
2866             {
2867                 addr_t section_base = eh_sym_section_sp->GetFileAddress();
2868                 addr_t offset = file_addr - section_base;
2869                 uint64_t symbol_id = m_symtab_ap->GetNumSymbols();
2870 
2871                 Symbol eh_symbol(
2872                         symbol_id,            // Symbol table index.
2873                         "???",                // Symbol name.
2874                         false,                // Is the symbol name mangled?
2875                         eSymbolTypeCode,      // Type of this symbol.
2876                         true,                 // Is this globally visible?
2877                         false,                // Is this symbol debug info?
2878                         false,                // Is this symbol a trampoline?
2879                         true,                 // Is this symbol artificial?
2880                         eh_sym_section_sp,    // Section in which this symbol is defined or null.
2881                         offset,               // Offset in section or symbol value.
2882                         range.GetByteSize(),  // Size in bytes of this symbol.
2883                         true,                 // Size is valid.
2884                         false,                // Contains linker annotations?
2885                         0);                   // Symbol flags.
2886                 if (symbol_id == m_symtab_ap->AddSymbol(eh_symbol))
2887                     return m_symtab_ap->SymbolAtIndex(symbol_id);
2888             }
2889         }
2890     }
2891     return nullptr;
2892 }
2893 
2894 
2895 bool
2896 ObjectFileELF::IsStripped ()
2897 {
2898     // TODO: determine this for ELF
2899     return false;
2900 }
2901 
2902 //===----------------------------------------------------------------------===//
2903 // Dump
2904 //
2905 // Dump the specifics of the runtime file container (such as any headers
2906 // segments, sections, etc).
2907 //----------------------------------------------------------------------
2908 void
2909 ObjectFileELF::Dump(Stream *s)
2910 {
2911     DumpELFHeader(s, m_header);
2912     s->EOL();
2913     DumpELFProgramHeaders(s);
2914     s->EOL();
2915     DumpELFSectionHeaders(s);
2916     s->EOL();
2917     SectionList *section_list = GetSectionList();
2918     if (section_list)
2919         section_list->Dump(s, NULL, true, UINT32_MAX);
2920     Symtab *symtab = GetSymtab();
2921     if (symtab)
2922         symtab->Dump(s, NULL, eSortOrderNone);
2923     s->EOL();
2924     DumpDependentModules(s);
2925     s->EOL();
2926 }
2927 
2928 //----------------------------------------------------------------------
2929 // DumpELFHeader
2930 //
2931 // Dump the ELF header to the specified output stream
2932 //----------------------------------------------------------------------
2933 void
2934 ObjectFileELF::DumpELFHeader(Stream *s, const ELFHeader &header)
2935 {
2936     s->PutCString("ELF Header\n");
2937     s->Printf("e_ident[EI_MAG0   ] = 0x%2.2x\n", header.e_ident[EI_MAG0]);
2938     s->Printf("e_ident[EI_MAG1   ] = 0x%2.2x '%c'\n",
2939               header.e_ident[EI_MAG1], header.e_ident[EI_MAG1]);
2940     s->Printf("e_ident[EI_MAG2   ] = 0x%2.2x '%c'\n",
2941               header.e_ident[EI_MAG2], header.e_ident[EI_MAG2]);
2942     s->Printf("e_ident[EI_MAG3   ] = 0x%2.2x '%c'\n",
2943               header.e_ident[EI_MAG3], header.e_ident[EI_MAG3]);
2944 
2945     s->Printf("e_ident[EI_CLASS  ] = 0x%2.2x\n", header.e_ident[EI_CLASS]);
2946     s->Printf("e_ident[EI_DATA   ] = 0x%2.2x ", header.e_ident[EI_DATA]);
2947     DumpELFHeader_e_ident_EI_DATA(s, header.e_ident[EI_DATA]);
2948     s->Printf ("\ne_ident[EI_VERSION] = 0x%2.2x\n", header.e_ident[EI_VERSION]);
2949     s->Printf ("e_ident[EI_PAD    ] = 0x%2.2x\n", header.e_ident[EI_PAD]);
2950 
2951     s->Printf("e_type      = 0x%4.4x ", header.e_type);
2952     DumpELFHeader_e_type(s, header.e_type);
2953     s->Printf("\ne_machine   = 0x%4.4x\n", header.e_machine);
2954     s->Printf("e_version   = 0x%8.8x\n", header.e_version);
2955     s->Printf("e_entry     = 0x%8.8" PRIx64 "\n", header.e_entry);
2956     s->Printf("e_phoff     = 0x%8.8" PRIx64 "\n", header.e_phoff);
2957     s->Printf("e_shoff     = 0x%8.8" PRIx64 "\n", header.e_shoff);
2958     s->Printf("e_flags     = 0x%8.8x\n", header.e_flags);
2959     s->Printf("e_ehsize    = 0x%4.4x\n", header.e_ehsize);
2960     s->Printf("e_phentsize = 0x%4.4x\n", header.e_phentsize);
2961     s->Printf("e_phnum     = 0x%4.4x\n", header.e_phnum);
2962     s->Printf("e_shentsize = 0x%4.4x\n", header.e_shentsize);
2963     s->Printf("e_shnum     = 0x%4.4x\n", header.e_shnum);
2964     s->Printf("e_shstrndx  = 0x%4.4x\n", header.e_shstrndx);
2965 }
2966 
2967 //----------------------------------------------------------------------
2968 // DumpELFHeader_e_type
2969 //
2970 // Dump an token value for the ELF header member e_type
2971 //----------------------------------------------------------------------
2972 void
2973 ObjectFileELF::DumpELFHeader_e_type(Stream *s, elf_half e_type)
2974 {
2975     switch (e_type)
2976     {
2977     case ET_NONE:   *s << "ET_NONE"; break;
2978     case ET_REL:    *s << "ET_REL"; break;
2979     case ET_EXEC:   *s << "ET_EXEC"; break;
2980     case ET_DYN:    *s << "ET_DYN"; break;
2981     case ET_CORE:   *s << "ET_CORE"; break;
2982     default:
2983         break;
2984     }
2985 }
2986 
2987 //----------------------------------------------------------------------
2988 // DumpELFHeader_e_ident_EI_DATA
2989 //
2990 // Dump an token value for the ELF header member e_ident[EI_DATA]
2991 //----------------------------------------------------------------------
2992 void
2993 ObjectFileELF::DumpELFHeader_e_ident_EI_DATA(Stream *s, unsigned char ei_data)
2994 {
2995     switch (ei_data)
2996     {
2997     case ELFDATANONE:   *s << "ELFDATANONE"; break;
2998     case ELFDATA2LSB:   *s << "ELFDATA2LSB - Little Endian"; break;
2999     case ELFDATA2MSB:   *s << "ELFDATA2MSB - Big Endian"; break;
3000     default:
3001         break;
3002     }
3003 }
3004 
3005 
3006 //----------------------------------------------------------------------
3007 // DumpELFProgramHeader
3008 //
3009 // Dump a single ELF program header to the specified output stream
3010 //----------------------------------------------------------------------
3011 void
3012 ObjectFileELF::DumpELFProgramHeader(Stream *s, const ELFProgramHeader &ph)
3013 {
3014     DumpELFProgramHeader_p_type(s, ph.p_type);
3015     s->Printf(" %8.8" PRIx64 " %8.8" PRIx64 " %8.8" PRIx64, ph.p_offset, ph.p_vaddr, ph.p_paddr);
3016     s->Printf(" %8.8" PRIx64 " %8.8" PRIx64 " %8.8x (", ph.p_filesz, ph.p_memsz, ph.p_flags);
3017 
3018     DumpELFProgramHeader_p_flags(s, ph.p_flags);
3019     s->Printf(") %8.8" PRIx64, ph.p_align);
3020 }
3021 
3022 //----------------------------------------------------------------------
3023 // DumpELFProgramHeader_p_type
3024 //
3025 // Dump an token value for the ELF program header member p_type which
3026 // describes the type of the program header
3027 // ----------------------------------------------------------------------
3028 void
3029 ObjectFileELF::DumpELFProgramHeader_p_type(Stream *s, elf_word p_type)
3030 {
3031     const int kStrWidth = 15;
3032     switch (p_type)
3033     {
3034     CASE_AND_STREAM(s, PT_NULL        , kStrWidth);
3035     CASE_AND_STREAM(s, PT_LOAD        , kStrWidth);
3036     CASE_AND_STREAM(s, PT_DYNAMIC     , kStrWidth);
3037     CASE_AND_STREAM(s, PT_INTERP      , kStrWidth);
3038     CASE_AND_STREAM(s, PT_NOTE        , kStrWidth);
3039     CASE_AND_STREAM(s, PT_SHLIB       , kStrWidth);
3040     CASE_AND_STREAM(s, PT_PHDR        , kStrWidth);
3041     CASE_AND_STREAM(s, PT_TLS         , kStrWidth);
3042     CASE_AND_STREAM(s, PT_GNU_EH_FRAME, kStrWidth);
3043     default:
3044         s->Printf("0x%8.8x%*s", p_type, kStrWidth - 10, "");
3045         break;
3046     }
3047 }
3048 
3049 
3050 //----------------------------------------------------------------------
3051 // DumpELFProgramHeader_p_flags
3052 //
3053 // Dump an token value for the ELF program header member p_flags
3054 //----------------------------------------------------------------------
3055 void
3056 ObjectFileELF::DumpELFProgramHeader_p_flags(Stream *s, elf_word p_flags)
3057 {
3058     *s  << ((p_flags & PF_X) ? "PF_X" : "    ")
3059         << (((p_flags & PF_X) && (p_flags & PF_W)) ? '+' : ' ')
3060         << ((p_flags & PF_W) ? "PF_W" : "    ")
3061         << (((p_flags & PF_W) && (p_flags & PF_R)) ? '+' : ' ')
3062         << ((p_flags & PF_R) ? "PF_R" : "    ");
3063 }
3064 
3065 //----------------------------------------------------------------------
3066 // DumpELFProgramHeaders
3067 //
3068 // Dump all of the ELF program header to the specified output stream
3069 //----------------------------------------------------------------------
3070 void
3071 ObjectFileELF::DumpELFProgramHeaders(Stream *s)
3072 {
3073     if (!ParseProgramHeaders())
3074         return;
3075 
3076     s->PutCString("Program Headers\n");
3077     s->PutCString("IDX  p_type          p_offset p_vaddr  p_paddr  "
3078                   "p_filesz p_memsz  p_flags                   p_align\n");
3079     s->PutCString("==== --------------- -------- -------- -------- "
3080                   "-------- -------- ------------------------- --------\n");
3081 
3082     uint32_t idx = 0;
3083     for (ProgramHeaderCollConstIter I = m_program_headers.begin();
3084          I != m_program_headers.end(); ++I, ++idx)
3085     {
3086         s->Printf("[%2u] ", idx);
3087         ObjectFileELF::DumpELFProgramHeader(s, *I);
3088         s->EOL();
3089     }
3090 }
3091 
3092 //----------------------------------------------------------------------
3093 // DumpELFSectionHeader
3094 //
3095 // Dump a single ELF section header to the specified output stream
3096 //----------------------------------------------------------------------
3097 void
3098 ObjectFileELF::DumpELFSectionHeader(Stream *s, const ELFSectionHeaderInfo &sh)
3099 {
3100     s->Printf("%8.8x ", sh.sh_name);
3101     DumpELFSectionHeader_sh_type(s, sh.sh_type);
3102     s->Printf(" %8.8" PRIx64 " (", sh.sh_flags);
3103     DumpELFSectionHeader_sh_flags(s, sh.sh_flags);
3104     s->Printf(") %8.8" PRIx64 " %8.8" PRIx64 " %8.8" PRIx64, sh.sh_addr, sh.sh_offset, sh.sh_size);
3105     s->Printf(" %8.8x %8.8x", sh.sh_link, sh.sh_info);
3106     s->Printf(" %8.8" PRIx64 " %8.8" PRIx64, sh.sh_addralign, sh.sh_entsize);
3107 }
3108 
3109 //----------------------------------------------------------------------
3110 // DumpELFSectionHeader_sh_type
3111 //
3112 // Dump an token value for the ELF section header member sh_type which
3113 // describes the type of the section
3114 //----------------------------------------------------------------------
3115 void
3116 ObjectFileELF::DumpELFSectionHeader_sh_type(Stream *s, elf_word sh_type)
3117 {
3118     const int kStrWidth = 12;
3119     switch (sh_type)
3120     {
3121     CASE_AND_STREAM(s, SHT_NULL     , kStrWidth);
3122     CASE_AND_STREAM(s, SHT_PROGBITS , kStrWidth);
3123     CASE_AND_STREAM(s, SHT_SYMTAB   , kStrWidth);
3124     CASE_AND_STREAM(s, SHT_STRTAB   , kStrWidth);
3125     CASE_AND_STREAM(s, SHT_RELA     , kStrWidth);
3126     CASE_AND_STREAM(s, SHT_HASH     , kStrWidth);
3127     CASE_AND_STREAM(s, SHT_DYNAMIC  , kStrWidth);
3128     CASE_AND_STREAM(s, SHT_NOTE     , kStrWidth);
3129     CASE_AND_STREAM(s, SHT_NOBITS   , kStrWidth);
3130     CASE_AND_STREAM(s, SHT_REL      , kStrWidth);
3131     CASE_AND_STREAM(s, SHT_SHLIB    , kStrWidth);
3132     CASE_AND_STREAM(s, SHT_DYNSYM   , kStrWidth);
3133     CASE_AND_STREAM(s, SHT_LOPROC   , kStrWidth);
3134     CASE_AND_STREAM(s, SHT_HIPROC   , kStrWidth);
3135     CASE_AND_STREAM(s, SHT_LOUSER   , kStrWidth);
3136     CASE_AND_STREAM(s, SHT_HIUSER   , kStrWidth);
3137     default:
3138         s->Printf("0x%8.8x%*s", sh_type, kStrWidth - 10, "");
3139         break;
3140     }
3141 }
3142 
3143 //----------------------------------------------------------------------
3144 // DumpELFSectionHeader_sh_flags
3145 //
3146 // Dump an token value for the ELF section header member sh_flags
3147 //----------------------------------------------------------------------
3148 void
3149 ObjectFileELF::DumpELFSectionHeader_sh_flags(Stream *s, elf_xword sh_flags)
3150 {
3151     *s  << ((sh_flags & SHF_WRITE) ? "WRITE" : "     ")
3152         << (((sh_flags & SHF_WRITE) && (sh_flags & SHF_ALLOC)) ? '+' : ' ')
3153         << ((sh_flags & SHF_ALLOC) ? "ALLOC" : "     ")
3154         << (((sh_flags & SHF_ALLOC) && (sh_flags & SHF_EXECINSTR)) ? '+' : ' ')
3155         << ((sh_flags & SHF_EXECINSTR) ? "EXECINSTR" : "         ");
3156 }
3157 
3158 //----------------------------------------------------------------------
3159 // DumpELFSectionHeaders
3160 //
3161 // Dump all of the ELF section header to the specified output stream
3162 //----------------------------------------------------------------------
3163 void
3164 ObjectFileELF::DumpELFSectionHeaders(Stream *s)
3165 {
3166     if (!ParseSectionHeaders())
3167         return;
3168 
3169     s->PutCString("Section Headers\n");
3170     s->PutCString("IDX  name     type         flags                            "
3171                   "addr     offset   size     link     info     addralgn "
3172                   "entsize  Name\n");
3173     s->PutCString("==== -------- ------------ -------------------------------- "
3174                   "-------- -------- -------- -------- -------- -------- "
3175                   "-------- ====================\n");
3176 
3177     uint32_t idx = 0;
3178     for (SectionHeaderCollConstIter I = m_section_headers.begin();
3179          I != m_section_headers.end(); ++I, ++idx)
3180     {
3181         s->Printf("[%2u] ", idx);
3182         ObjectFileELF::DumpELFSectionHeader(s, *I);
3183         const char* section_name = I->section_name.AsCString("");
3184         if (section_name)
3185             *s << ' ' << section_name << "\n";
3186     }
3187 }
3188 
3189 void
3190 ObjectFileELF::DumpDependentModules(lldb_private::Stream *s)
3191 {
3192     size_t num_modules = ParseDependentModules();
3193 
3194     if (num_modules > 0)
3195     {
3196         s->PutCString("Dependent Modules:\n");
3197         for (unsigned i = 0; i < num_modules; ++i)
3198         {
3199             const FileSpec &spec = m_filespec_ap->GetFileSpecAtIndex(i);
3200             s->Printf("   %s\n", spec.GetFilename().GetCString());
3201         }
3202     }
3203 }
3204 
3205 bool
3206 ObjectFileELF::GetArchitecture (ArchSpec &arch)
3207 {
3208     if (!ParseHeader())
3209         return false;
3210 
3211     if (m_section_headers.empty())
3212     {
3213         // Allow elf notes to be parsed which may affect the detected architecture.
3214         ParseSectionHeaders();
3215     }
3216 
3217     if (CalculateType() == eTypeCoreFile && m_arch_spec.TripleOSIsUnspecifiedUnknown())
3218     {
3219         // Core files don't have section headers yet they have PT_NOTE program headers
3220         // that might shed more light on the architecture
3221         if (ParseProgramHeaders())
3222         {
3223             for (size_t i = 0, count = GetProgramHeaderCount(); i < count; ++i)
3224             {
3225                 const elf::ELFProgramHeader* header = GetProgramHeaderByIndex(i);
3226                 if (header && header->p_type == PT_NOTE && header->p_offset != 0 && header->p_filesz > 0)
3227                 {
3228                     DataExtractor data;
3229                     if (data.SetData (m_data, header->p_offset, header->p_filesz) == header->p_filesz)
3230                     {
3231                         lldb_private::UUID uuid;
3232                         RefineModuleDetailsFromNote (data, m_arch_spec, uuid);
3233                     }
3234                 }
3235             }
3236         }
3237     }
3238     arch = m_arch_spec;
3239     return true;
3240 }
3241 
3242 ObjectFile::Type
3243 ObjectFileELF::CalculateType()
3244 {
3245     switch (m_header.e_type)
3246     {
3247         case llvm::ELF::ET_NONE:
3248             // 0 - No file type
3249             return eTypeUnknown;
3250 
3251         case llvm::ELF::ET_REL:
3252             // 1 - Relocatable file
3253             return eTypeObjectFile;
3254 
3255         case llvm::ELF::ET_EXEC:
3256             // 2 - Executable file
3257             return eTypeExecutable;
3258 
3259         case llvm::ELF::ET_DYN:
3260             // 3 - Shared object file
3261             return eTypeSharedLibrary;
3262 
3263         case ET_CORE:
3264             // 4 - Core file
3265             return eTypeCoreFile;
3266 
3267         default:
3268             break;
3269     }
3270     return eTypeUnknown;
3271 }
3272 
3273 ObjectFile::Strata
3274 ObjectFileELF::CalculateStrata()
3275 {
3276     switch (m_header.e_type)
3277     {
3278         case llvm::ELF::ET_NONE:
3279             // 0 - No file type
3280             return eStrataUnknown;
3281 
3282         case llvm::ELF::ET_REL:
3283             // 1 - Relocatable file
3284             return eStrataUnknown;
3285 
3286         case llvm::ELF::ET_EXEC:
3287             // 2 - Executable file
3288             // TODO: is there any way to detect that an executable is a kernel
3289             // related executable by inspecting the program headers, section
3290             // headers, symbols, or any other flag bits???
3291             return eStrataUser;
3292 
3293         case llvm::ELF::ET_DYN:
3294             // 3 - Shared object file
3295             // TODO: is there any way to detect that an shared library is a kernel
3296             // related executable by inspecting the program headers, section
3297             // headers, symbols, or any other flag bits???
3298             return eStrataUnknown;
3299 
3300         case ET_CORE:
3301             // 4 - Core file
3302             // TODO: is there any way to detect that an core file is a kernel
3303             // related executable by inspecting the program headers, section
3304             // headers, symbols, or any other flag bits???
3305             return eStrataUnknown;
3306 
3307         default:
3308             break;
3309     }
3310     return eStrataUnknown;
3311 }
3312 
3313