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_3:
334         case llvm::ELF::EF_MIPS_ARCH_4:
335         case llvm::ELF::EF_MIPS_ARCH_5:
336         case llvm::ELF::EF_MIPS_ARCH_32:
337             return (endian == ELFDATA2LSB) ? ArchSpec::eMIPSSubType_mips32el : ArchSpec::eMIPSSubType_mips32;
338         case llvm::ELF::EF_MIPS_ARCH_32R2:
339             return (endian == ELFDATA2LSB) ? ArchSpec::eMIPSSubType_mips32r2el : ArchSpec::eMIPSSubType_mips32r2;
340         case llvm::ELF::EF_MIPS_ARCH_32R6:
341             return (endian == ELFDATA2LSB) ? ArchSpec::eMIPSSubType_mips32r6el : ArchSpec::eMIPSSubType_mips32r6;
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 // Top 16 bits of the `Symbol` flags are available.
958 #define ARM_ELF_SYM_IS_THUMB    (1 << 16)
959 
960 AddressClass
961 ObjectFileELF::GetAddressClass (addr_t file_addr)
962 {
963     Symtab* symtab = GetSymtab();
964     if (!symtab)
965         return eAddressClassUnknown;
966 
967     // The address class is determined based on the symtab. Ask it from the object file what
968     // contains the symtab information.
969     ObjectFile* symtab_objfile = symtab->GetObjectFile();
970     if (symtab_objfile != nullptr && symtab_objfile != this)
971         return symtab_objfile->GetAddressClass(file_addr);
972 
973     auto res = ObjectFile::GetAddressClass (file_addr);
974     if (res != eAddressClassCode)
975         return res;
976 
977     auto ub = m_address_class_map.upper_bound(file_addr);
978     if (ub == m_address_class_map.begin())
979     {
980         // No entry in the address class map before the address. Return
981         // default address class for an address in a code section.
982         return eAddressClassCode;
983     }
984 
985     // Move iterator to the address class entry preceding address
986     --ub;
987 
988     return ub->second;
989 }
990 
991 size_t
992 ObjectFileELF::SectionIndex(const SectionHeaderCollIter &I)
993 {
994     return std::distance(m_section_headers.begin(), I) + 1u;
995 }
996 
997 size_t
998 ObjectFileELF::SectionIndex(const SectionHeaderCollConstIter &I) const
999 {
1000     return std::distance(m_section_headers.begin(), I) + 1u;
1001 }
1002 
1003 bool
1004 ObjectFileELF::ParseHeader()
1005 {
1006     lldb::offset_t offset = 0;
1007     if (!m_header.Parse(m_data, &offset))
1008         return false;
1009 
1010     if (!IsInMemory())
1011         return true;
1012 
1013     // For in memory object files m_data might not contain the full object file. Try to load it
1014     // until the end of the "Section header table" what is at the end of the ELF file.
1015     addr_t file_size = m_header.e_shoff + m_header.e_shnum * m_header.e_shentsize;
1016     if (m_data.GetByteSize() < file_size)
1017     {
1018         ProcessSP process_sp (m_process_wp.lock());
1019         if (!process_sp)
1020             return false;
1021 
1022         DataBufferSP data_sp = ReadMemory(process_sp, m_memory_addr, file_size);
1023         if (!data_sp)
1024             return false;
1025         m_data.SetData(data_sp, 0, file_size);
1026     }
1027 
1028     return true;
1029 }
1030 
1031 bool
1032 ObjectFileELF::GetUUID(lldb_private::UUID* uuid)
1033 {
1034     // Need to parse the section list to get the UUIDs, so make sure that's been done.
1035     if (!ParseSectionHeaders() && GetType() != ObjectFile::eTypeCoreFile)
1036         return false;
1037 
1038     if (m_uuid.IsValid())
1039     {
1040         // We have the full build id uuid.
1041         *uuid = m_uuid;
1042         return true;
1043     }
1044     else if (GetType() == ObjectFile::eTypeCoreFile)
1045     {
1046         uint32_t core_notes_crc = 0;
1047 
1048         if (!ParseProgramHeaders())
1049             return false;
1050 
1051         core_notes_crc = CalculateELFNotesSegmentsCRC32(m_program_headers, m_data);
1052 
1053         if (core_notes_crc)
1054         {
1055             // Use 8 bytes - first 4 bytes for *magic* prefix, mainly to make it
1056             // look different form .gnu_debuglink crc - followed by 4 bytes of note
1057             // segments crc.
1058             uint32_t uuidt[4] = { g_core_uuid_magic, core_notes_crc, 0, 0 };
1059             m_uuid.SetBytes (uuidt, sizeof(uuidt));
1060         }
1061     }
1062     else
1063     {
1064         if (!m_gnu_debuglink_crc)
1065             m_gnu_debuglink_crc = calc_gnu_debuglink_crc32 (m_data.GetDataStart(), m_data.GetByteSize());
1066         if (m_gnu_debuglink_crc)
1067         {
1068             // Use 4 bytes of crc from the .gnu_debuglink section.
1069             uint32_t uuidt[4] = { m_gnu_debuglink_crc, 0, 0, 0 };
1070             m_uuid.SetBytes (uuidt, sizeof(uuidt));
1071         }
1072     }
1073 
1074     if (m_uuid.IsValid())
1075     {
1076         *uuid = m_uuid;
1077         return true;
1078     }
1079 
1080     return false;
1081 }
1082 
1083 lldb_private::FileSpecList
1084 ObjectFileELF::GetDebugSymbolFilePaths()
1085 {
1086     FileSpecList file_spec_list;
1087 
1088     if (!m_gnu_debuglink_file.empty())
1089     {
1090         FileSpec file_spec (m_gnu_debuglink_file.c_str(), false);
1091         file_spec_list.Append (file_spec);
1092     }
1093     return file_spec_list;
1094 }
1095 
1096 uint32_t
1097 ObjectFileELF::GetDependentModules(FileSpecList &files)
1098 {
1099     size_t num_modules = ParseDependentModules();
1100     uint32_t num_specs = 0;
1101 
1102     for (unsigned i = 0; i < num_modules; ++i)
1103     {
1104         if (files.AppendIfUnique(m_filespec_ap->GetFileSpecAtIndex(i)))
1105             num_specs++;
1106     }
1107 
1108     return num_specs;
1109 }
1110 
1111 Address
1112 ObjectFileELF::GetImageInfoAddress(Target *target)
1113 {
1114     if (!ParseDynamicSymbols())
1115         return Address();
1116 
1117     SectionList *section_list = GetSectionList();
1118     if (!section_list)
1119         return Address();
1120 
1121     // Find the SHT_DYNAMIC (.dynamic) section.
1122     SectionSP dynsym_section_sp (section_list->FindSectionByType (eSectionTypeELFDynamicLinkInfo, true));
1123     if (!dynsym_section_sp)
1124         return Address();
1125     assert (dynsym_section_sp->GetObjectFile() == this);
1126 
1127     user_id_t dynsym_id = dynsym_section_sp->GetID();
1128     const ELFSectionHeaderInfo *dynsym_hdr = GetSectionHeaderByIndex(dynsym_id);
1129     if (!dynsym_hdr)
1130         return Address();
1131 
1132     for (size_t i = 0; i < m_dynamic_symbols.size(); ++i)
1133     {
1134         ELFDynamic &symbol = m_dynamic_symbols[i];
1135 
1136         if (symbol.d_tag == DT_DEBUG)
1137         {
1138             // Compute the offset as the number of previous entries plus the
1139             // size of d_tag.
1140             addr_t offset = i * dynsym_hdr->sh_entsize + GetAddressByteSize();
1141             return Address(dynsym_section_sp, offset);
1142         }
1143         // MIPS executables uses DT_MIPS_RLD_MAP_REL to support PIE. DT_MIPS_RLD_MAP exists in non-PIE.
1144         else if ((symbol.d_tag == DT_MIPS_RLD_MAP || symbol.d_tag == DT_MIPS_RLD_MAP_REL) && target)
1145         {
1146             addr_t offset = i * dynsym_hdr->sh_entsize + GetAddressByteSize();
1147             addr_t dyn_base = dynsym_section_sp->GetLoadBaseAddress(target);
1148             if (dyn_base == LLDB_INVALID_ADDRESS)
1149                 return Address();
1150 
1151             Error error;
1152             if (symbol.d_tag == DT_MIPS_RLD_MAP)
1153             {
1154                 // DT_MIPS_RLD_MAP tag stores an absolute address of the debug pointer.
1155                 Address addr;
1156                 if (target->ReadPointerFromMemory(dyn_base + offset, false, error, addr))
1157                     return addr;
1158             }
1159             if (symbol.d_tag == DT_MIPS_RLD_MAP_REL)
1160             {
1161                 // DT_MIPS_RLD_MAP_REL tag stores the offset to the debug pointer, relative to the address of the tag.
1162                 uint64_t rel_offset;
1163                 rel_offset = target->ReadUnsignedIntegerFromMemory(dyn_base + offset, false, GetAddressByteSize(), UINT64_MAX, error);
1164                 if (error.Success() && rel_offset != UINT64_MAX)
1165                 {
1166                     Address addr;
1167                     addr_t debug_ptr_address = dyn_base + (offset - GetAddressByteSize()) + rel_offset;
1168                     addr.SetOffset (debug_ptr_address);
1169                     return addr;
1170                 }
1171             }
1172         }
1173     }
1174 
1175     return Address();
1176 }
1177 
1178 lldb_private::Address
1179 ObjectFileELF::GetEntryPointAddress ()
1180 {
1181     if (m_entry_point_address.IsValid())
1182         return m_entry_point_address;
1183 
1184     if (!ParseHeader() || !IsExecutable())
1185         return m_entry_point_address;
1186 
1187     SectionList *section_list = GetSectionList();
1188     addr_t offset = m_header.e_entry;
1189 
1190     if (!section_list)
1191         m_entry_point_address.SetOffset(offset);
1192     else
1193         m_entry_point_address.ResolveAddressUsingFileSections(offset, section_list);
1194     return m_entry_point_address;
1195 }
1196 
1197 //----------------------------------------------------------------------
1198 // ParseDependentModules
1199 //----------------------------------------------------------------------
1200 size_t
1201 ObjectFileELF::ParseDependentModules()
1202 {
1203     if (m_filespec_ap.get())
1204         return m_filespec_ap->GetSize();
1205 
1206     m_filespec_ap.reset(new FileSpecList());
1207 
1208     if (!ParseSectionHeaders())
1209         return 0;
1210 
1211     SectionList *section_list = GetSectionList();
1212     if (!section_list)
1213         return 0;
1214 
1215     // Find the SHT_DYNAMIC section.
1216     Section *dynsym = section_list->FindSectionByType (eSectionTypeELFDynamicLinkInfo, true).get();
1217     if (!dynsym)
1218         return 0;
1219     assert (dynsym->GetObjectFile() == this);
1220 
1221     const ELFSectionHeaderInfo *header = GetSectionHeaderByIndex (dynsym->GetID());
1222     if (!header)
1223         return 0;
1224     // sh_link: section header index of string table used by entries in the section.
1225     Section *dynstr = section_list->FindSectionByID (header->sh_link + 1).get();
1226     if (!dynstr)
1227         return 0;
1228 
1229     DataExtractor dynsym_data;
1230     DataExtractor dynstr_data;
1231     if (ReadSectionData(dynsym, dynsym_data) &&
1232         ReadSectionData(dynstr, dynstr_data))
1233     {
1234         ELFDynamic symbol;
1235         const lldb::offset_t section_size = dynsym_data.GetByteSize();
1236         lldb::offset_t offset = 0;
1237 
1238         // The only type of entries we are concerned with are tagged DT_NEEDED,
1239         // yielding the name of a required library.
1240         while (offset < section_size)
1241         {
1242             if (!symbol.Parse(dynsym_data, &offset))
1243                 break;
1244 
1245             if (symbol.d_tag != DT_NEEDED)
1246                 continue;
1247 
1248             uint32_t str_index = static_cast<uint32_t>(symbol.d_val);
1249             const char *lib_name = dynstr_data.PeekCStr(str_index);
1250             m_filespec_ap->Append(FileSpec(lib_name, true));
1251         }
1252     }
1253 
1254     return m_filespec_ap->GetSize();
1255 }
1256 
1257 //----------------------------------------------------------------------
1258 // GetProgramHeaderInfo
1259 //----------------------------------------------------------------------
1260 size_t
1261 ObjectFileELF::GetProgramHeaderInfo(ProgramHeaderColl &program_headers,
1262                                     DataExtractor &object_data,
1263                                     const ELFHeader &header)
1264 {
1265     // We have already parsed the program headers
1266     if (!program_headers.empty())
1267         return program_headers.size();
1268 
1269     // If there are no program headers to read we are done.
1270     if (header.e_phnum == 0)
1271         return 0;
1272 
1273     program_headers.resize(header.e_phnum);
1274     if (program_headers.size() != header.e_phnum)
1275         return 0;
1276 
1277     const size_t ph_size = header.e_phnum * header.e_phentsize;
1278     const elf_off ph_offset = header.e_phoff;
1279     DataExtractor data;
1280     if (data.SetData(object_data, ph_offset, ph_size) != ph_size)
1281         return 0;
1282 
1283     uint32_t idx;
1284     lldb::offset_t offset;
1285     for (idx = 0, offset = 0; idx < header.e_phnum; ++idx)
1286     {
1287         if (program_headers[idx].Parse(data, &offset) == false)
1288             break;
1289     }
1290 
1291     if (idx < program_headers.size())
1292         program_headers.resize(idx);
1293 
1294     return program_headers.size();
1295 
1296 }
1297 
1298 //----------------------------------------------------------------------
1299 // ParseProgramHeaders
1300 //----------------------------------------------------------------------
1301 size_t
1302 ObjectFileELF::ParseProgramHeaders()
1303 {
1304     return GetProgramHeaderInfo(m_program_headers, m_data, m_header);
1305 }
1306 
1307 lldb_private::Error
1308 ObjectFileELF::RefineModuleDetailsFromNote (lldb_private::DataExtractor &data, lldb_private::ArchSpec &arch_spec, lldb_private::UUID &uuid)
1309 {
1310     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_MODULES));
1311     Error error;
1312 
1313     lldb::offset_t offset = 0;
1314 
1315     while (true)
1316     {
1317         // Parse the note header.  If this fails, bail out.
1318         const lldb::offset_t note_offset = offset;
1319         ELFNote note = ELFNote();
1320         if (!note.Parse(data, &offset))
1321         {
1322             // We're done.
1323             return error;
1324         }
1325 
1326         if (log)
1327             log->Printf ("ObjectFileELF::%s parsing note name='%s', type=%" PRIu32, __FUNCTION__, note.n_name.c_str (), note.n_type);
1328 
1329         // Process FreeBSD ELF notes.
1330         if ((note.n_name == LLDB_NT_OWNER_FREEBSD) &&
1331             (note.n_type == LLDB_NT_FREEBSD_ABI_TAG) &&
1332             (note.n_descsz == LLDB_NT_FREEBSD_ABI_SIZE))
1333         {
1334             // Pull out the min version info.
1335             uint32_t version_info;
1336             if (data.GetU32 (&offset, &version_info, 1) == nullptr)
1337             {
1338                 error.SetErrorString ("failed to read FreeBSD ABI note payload");
1339                 return error;
1340             }
1341 
1342             // Convert the version info into a major/minor number.
1343             const uint32_t version_major = version_info / 100000;
1344             const uint32_t version_minor = (version_info / 1000) % 100;
1345 
1346             char os_name[32];
1347             snprintf (os_name, sizeof (os_name), "freebsd%" PRIu32 ".%" PRIu32, version_major, version_minor);
1348 
1349             // Set the elf OS version to FreeBSD.  Also clear the vendor.
1350             arch_spec.GetTriple ().setOSName (os_name);
1351             arch_spec.GetTriple ().setVendor (llvm::Triple::VendorType::UnknownVendor);
1352 
1353             if (log)
1354                 log->Printf ("ObjectFileELF::%s detected FreeBSD %" PRIu32 ".%" PRIu32 ".%" PRIu32, __FUNCTION__, version_major, version_minor, static_cast<uint32_t> (version_info % 1000));
1355         }
1356         // Process GNU ELF notes.
1357         else if (note.n_name == LLDB_NT_OWNER_GNU)
1358         {
1359             switch (note.n_type)
1360             {
1361                 case LLDB_NT_GNU_ABI_TAG:
1362                     if (note.n_descsz == LLDB_NT_GNU_ABI_SIZE)
1363                     {
1364                         // Pull out the min OS version supporting the ABI.
1365                         uint32_t version_info[4];
1366                         if (data.GetU32 (&offset, &version_info[0], note.n_descsz / 4) == nullptr)
1367                         {
1368                             error.SetErrorString ("failed to read GNU ABI note payload");
1369                             return error;
1370                         }
1371 
1372                         // Set the OS per the OS field.
1373                         switch (version_info[0])
1374                         {
1375                             case LLDB_NT_GNU_ABI_OS_LINUX:
1376                                 arch_spec.GetTriple ().setOS (llvm::Triple::OSType::Linux);
1377                                 arch_spec.GetTriple ().setVendor (llvm::Triple::VendorType::UnknownVendor);
1378                                 if (log)
1379                                     log->Printf ("ObjectFileELF::%s detected Linux, min version %" PRIu32 ".%" PRIu32 ".%" PRIu32, __FUNCTION__, version_info[1], version_info[2], version_info[3]);
1380                                 // 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.
1381                                 break;
1382                             case LLDB_NT_GNU_ABI_OS_HURD:
1383                                 arch_spec.GetTriple ().setOS (llvm::Triple::OSType::UnknownOS);
1384                                 arch_spec.GetTriple ().setVendor (llvm::Triple::VendorType::UnknownVendor);
1385                                 if (log)
1386                                     log->Printf ("ObjectFileELF::%s detected Hurd (unsupported), min version %" PRIu32 ".%" PRIu32 ".%" PRIu32, __FUNCTION__, version_info[1], version_info[2], version_info[3]);
1387                                 break;
1388                             case LLDB_NT_GNU_ABI_OS_SOLARIS:
1389                                 arch_spec.GetTriple ().setOS (llvm::Triple::OSType::Solaris);
1390                                 arch_spec.GetTriple ().setVendor (llvm::Triple::VendorType::UnknownVendor);
1391                                 if (log)
1392                                     log->Printf ("ObjectFileELF::%s detected Solaris, min version %" PRIu32 ".%" PRIu32 ".%" PRIu32, __FUNCTION__, version_info[1], version_info[2], version_info[3]);
1393                                 break;
1394                             default:
1395                                 if (log)
1396                                     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]);
1397                                 break;
1398                         }
1399                     }
1400                     break;
1401 
1402                 case LLDB_NT_GNU_BUILD_ID_TAG:
1403                     // Only bother processing this if we don't already have the uuid set.
1404                     if (!uuid.IsValid())
1405                     {
1406                         // 16 bytes is UUID|MD5, 20 bytes is SHA1
1407                         if ((note.n_descsz == 16 || note.n_descsz == 20))
1408                         {
1409                             uint8_t uuidbuf[20];
1410                             if (data.GetU8 (&offset, &uuidbuf, note.n_descsz) == nullptr)
1411                             {
1412                                 error.SetErrorString ("failed to read GNU_BUILD_ID note payload");
1413                                 return error;
1414                             }
1415 
1416                             // Save the build id as the UUID for the module.
1417                             uuid.SetBytes (uuidbuf, note.n_descsz);
1418                         }
1419                     }
1420                     break;
1421             }
1422         }
1423         // Process NetBSD ELF notes.
1424         else if ((note.n_name == LLDB_NT_OWNER_NETBSD) &&
1425                  (note.n_type == LLDB_NT_NETBSD_ABI_TAG) &&
1426                  (note.n_descsz == LLDB_NT_NETBSD_ABI_SIZE))
1427         {
1428             // Pull out the min version info.
1429             uint32_t version_info;
1430             if (data.GetU32 (&offset, &version_info, 1) == nullptr)
1431             {
1432                 error.SetErrorString ("failed to read NetBSD ABI note payload");
1433                 return error;
1434             }
1435 
1436             // Set the elf OS version to NetBSD.  Also clear the vendor.
1437             arch_spec.GetTriple ().setOS (llvm::Triple::OSType::NetBSD);
1438             arch_spec.GetTriple ().setVendor (llvm::Triple::VendorType::UnknownVendor);
1439 
1440             if (log)
1441                 log->Printf ("ObjectFileELF::%s detected NetBSD, min version constant %" PRIu32, __FUNCTION__, version_info);
1442         }
1443         // Process CSR kalimba notes
1444         else if ((note.n_type == LLDB_NT_GNU_ABI_TAG) &&
1445                 (note.n_name == LLDB_NT_OWNER_CSR))
1446         {
1447             arch_spec.GetTriple().setOS(llvm::Triple::OSType::UnknownOS);
1448             arch_spec.GetTriple().setVendor(llvm::Triple::VendorType::CSR);
1449 
1450             // TODO At some point the description string could be processed.
1451             // It could provide a steer towards the kalimba variant which
1452             // this ELF targets.
1453             if(note.n_descsz)
1454             {
1455                 const char *cstr = data.GetCStr(&offset, llvm::RoundUpToAlignment (note.n_descsz, 4));
1456                 (void)cstr;
1457             }
1458         }
1459         else if (note.n_name == LLDB_NT_OWNER_ANDROID)
1460         {
1461             arch_spec.GetTriple().setOS(llvm::Triple::OSType::Linux);
1462             arch_spec.GetTriple().setEnvironment(llvm::Triple::EnvironmentType::Android);
1463         }
1464         else if (note.n_name == LLDB_NT_OWNER_LINUX)
1465         {
1466             // This is sometimes found in core files and usually contains extended register info
1467             arch_spec.GetTriple().setOS(llvm::Triple::OSType::Linux);
1468         }
1469         else if (note.n_name == LLDB_NT_OWNER_CORE)
1470         {
1471             // Parse the NT_FILE to look for stuff in paths to shared libraries
1472             // As the contents look like:
1473             // count     = 0x000000000000000a (10)
1474             // page_size = 0x0000000000001000 (4096)
1475             // Index start              end                file_ofs           path
1476             // ===== ------------------ ------------------ ------------------ -------------------------------------
1477             // [  0] 0x0000000000400000 0x0000000000401000 0x0000000000000000 /tmp/a.out
1478             // [  1] 0x0000000000600000 0x0000000000601000 0x0000000000000000 /tmp/a.out
1479             // [  2] 0x0000000000601000 0x0000000000602000 0x0000000000000001 /tmp/a.out
1480             // [  3] 0x00007fa79c9ed000 0x00007fa79cba8000 0x0000000000000000 /lib/x86_64-linux-gnu/libc-2.19.so
1481             // [  4] 0x00007fa79cba8000 0x00007fa79cda7000 0x00000000000001bb /lib/x86_64-linux-gnu/libc-2.19.so
1482             // [  5] 0x00007fa79cda7000 0x00007fa79cdab000 0x00000000000001ba /lib/x86_64-linux-gnu/libc-2.19.so
1483             // [  6] 0x00007fa79cdab000 0x00007fa79cdad000 0x00000000000001be /lib/x86_64-linux-gnu/libc-2.19.so
1484             // [  7] 0x00007fa79cdb2000 0x00007fa79cdd5000 0x0000000000000000 /lib/x86_64-linux-gnu/ld-2.19.so
1485             // [  8] 0x00007fa79cfd4000 0x00007fa79cfd5000 0x0000000000000022 /lib/x86_64-linux-gnu/ld-2.19.so
1486             // [  9] 0x00007fa79cfd5000 0x00007fa79cfd6000 0x0000000000000023 /lib/x86_64-linux-gnu/ld-2.19.so
1487             if (note.n_type == NT_FILE)
1488             {
1489                 uint64_t count = data.GetU64(&offset);
1490                 offset += 8 + 3*8*count; // Skip page size and all start/end/file_ofs
1491                 for (size_t i=0; i<count; ++i)
1492                 {
1493                     llvm::StringRef path(data.GetCStr(&offset));
1494                     if (path.startswith("/lib/x86_64-linux-gnu"))
1495                     {
1496                         arch_spec.GetTriple().setOS(llvm::Triple::OSType::Linux);
1497                         break;
1498                     }
1499                 }
1500             }
1501         }
1502 
1503         // Calculate the offset of the next note just in case "offset" has been used
1504         // to poke at the contents of the note data
1505         offset = note_offset + note.GetByteSize();
1506     }
1507 
1508     return error;
1509 }
1510 
1511 
1512 //----------------------------------------------------------------------
1513 // GetSectionHeaderInfo
1514 //----------------------------------------------------------------------
1515 size_t
1516 ObjectFileELF::GetSectionHeaderInfo(SectionHeaderColl &section_headers,
1517                                     lldb_private::DataExtractor &object_data,
1518                                     const elf::ELFHeader &header,
1519                                     lldb_private::UUID &uuid,
1520                                     std::string &gnu_debuglink_file,
1521                                     uint32_t &gnu_debuglink_crc,
1522                                     ArchSpec &arch_spec)
1523 {
1524     // Don't reparse the section headers if we already did that.
1525     if (!section_headers.empty())
1526         return section_headers.size();
1527 
1528     // Only initialize the arch_spec to okay defaults if they're not already set.
1529     // We'll refine this with note data as we parse the notes.
1530     if (arch_spec.GetTriple ().getOS () == llvm::Triple::OSType::UnknownOS)
1531     {
1532         llvm::Triple::OSType ostype;
1533         llvm::Triple::OSType spec_ostype;
1534         const uint32_t sub_type = subTypeFromElfHeader(header);
1535         arch_spec.SetArchitecture (eArchTypeELF, header.e_machine, sub_type, header.e_ident[EI_OSABI]);
1536         //
1537         // Validate if it is ok to remove GetOsFromOSABI
1538         GetOsFromOSABI (header.e_ident[EI_OSABI], ostype);
1539         spec_ostype = arch_spec.GetTriple ().getOS ();
1540         assert(spec_ostype == ostype);
1541     }
1542 
1543     if (arch_spec.GetMachine() == llvm::Triple::mips || arch_spec.GetMachine() == llvm::Triple::mipsel
1544         || arch_spec.GetMachine() == llvm::Triple::mips64 || arch_spec.GetMachine() == llvm::Triple::mips64el)
1545     {
1546         switch (header.e_flags & llvm::ELF::EF_MIPS_ARCH_ASE)
1547         {
1548             case llvm::ELF::EF_MIPS_MICROMIPS:
1549                 arch_spec.SetFlags (ArchSpec::eMIPSAse_micromips);
1550                 break;
1551             case llvm::ELF::EF_MIPS_ARCH_ASE_M16:
1552                 arch_spec.SetFlags (ArchSpec::eMIPSAse_mips16);
1553                 break;
1554             case llvm::ELF::EF_MIPS_ARCH_ASE_MDMX:
1555                 arch_spec.SetFlags (ArchSpec::eMIPSAse_mdmx);
1556                 break;
1557             default:
1558                 break;
1559         }
1560     }
1561 
1562     // If there are no section headers we are done.
1563     if (header.e_shnum == 0) {
1564 #if 0
1565         if (arch_spec.GetTriple().getOS() == llvm::Triple::OSType::UnknownOS)
1566             arch_spec.GetTriple().setOSName(HostInfo::GetOSString().data());
1567 #endif
1568         return 0;
1569     }
1570 
1571     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_MODULES));
1572 
1573     section_headers.resize(header.e_shnum);
1574     if (section_headers.size() != header.e_shnum)
1575         return 0;
1576 
1577     const size_t sh_size = header.e_shnum * header.e_shentsize;
1578     const elf_off sh_offset = header.e_shoff;
1579     DataExtractor sh_data;
1580     if (sh_data.SetData (object_data, sh_offset, sh_size) != sh_size)
1581         return 0;
1582 
1583     uint32_t idx;
1584     lldb::offset_t offset;
1585     for (idx = 0, offset = 0; idx < header.e_shnum; ++idx)
1586     {
1587         if (section_headers[idx].Parse(sh_data, &offset) == false)
1588             break;
1589     }
1590     if (idx < section_headers.size())
1591         section_headers.resize(idx);
1592 
1593     const unsigned strtab_idx = header.e_shstrndx;
1594     if (strtab_idx && strtab_idx < section_headers.size())
1595     {
1596         const ELFSectionHeaderInfo &sheader = section_headers[strtab_idx];
1597         const size_t byte_size = sheader.sh_size;
1598         const Elf64_Off offset = sheader.sh_offset;
1599         lldb_private::DataExtractor shstr_data;
1600 
1601         if (shstr_data.SetData (object_data, offset, byte_size) == byte_size)
1602         {
1603             for (SectionHeaderCollIter I = section_headers.begin();
1604                  I != section_headers.end(); ++I)
1605             {
1606                 static ConstString g_sect_name_gnu_debuglink (".gnu_debuglink");
1607                 const ELFSectionHeaderInfo &sheader = *I;
1608                 const uint64_t section_size = sheader.sh_type == SHT_NOBITS ? 0 : sheader.sh_size;
1609                 ConstString name(shstr_data.PeekCStr(I->sh_name));
1610 
1611                 I->section_name = name;
1612 
1613                 if (arch_spec.GetMachine() == llvm::Triple::mips || arch_spec.GetMachine() == llvm::Triple::mipsel
1614                     || arch_spec.GetMachine() == llvm::Triple::mips64 || arch_spec.GetMachine() == llvm::Triple::mips64el)
1615                 {
1616                     uint32_t arch_flags = arch_spec.GetFlags ();
1617                     DataExtractor data;
1618                     if (sheader.sh_type == SHT_MIPS_ABIFLAGS)
1619                     {
1620 
1621                         if (section_size && (data.SetData (object_data, sheader.sh_offset, section_size) == section_size))
1622                         {
1623                             lldb::offset_t ase_offset = 12; // MIPS ABI Flags Version: 0
1624                             arch_flags |= data.GetU32 (&ase_offset);
1625                         }
1626                     }
1627                     // Settings appropriate ArchSpec ABI Flags
1628                     if (header.e_flags & llvm::ELF::EF_MIPS_ABI2)
1629                     {
1630                         arch_flags |= lldb_private::ArchSpec::eMIPSABI_N32;
1631                     }
1632                     else if (header.e_flags & llvm::ELF::EF_MIPS_ABI_O32)
1633                     {
1634                          arch_flags |= lldb_private::ArchSpec::eMIPSABI_O32;
1635                     }
1636                     arch_spec.SetFlags (arch_flags);
1637                 }
1638 
1639                 if (name == g_sect_name_gnu_debuglink)
1640                 {
1641                     DataExtractor data;
1642                     if (section_size && (data.SetData (object_data, sheader.sh_offset, section_size) == section_size))
1643                     {
1644                         lldb::offset_t gnu_debuglink_offset = 0;
1645                         gnu_debuglink_file = data.GetCStr (&gnu_debuglink_offset);
1646                         gnu_debuglink_offset = llvm::RoundUpToAlignment (gnu_debuglink_offset, 4);
1647                         data.GetU32 (&gnu_debuglink_offset, &gnu_debuglink_crc, 1);
1648                     }
1649                 }
1650 
1651                 // Process ELF note section entries.
1652                 bool is_note_header = (sheader.sh_type == SHT_NOTE);
1653 
1654                 // The section header ".note.android.ident" is stored as a
1655                 // PROGBITS type header but it is actually a note header.
1656                 static ConstString g_sect_name_android_ident (".note.android.ident");
1657                 if (!is_note_header && name == g_sect_name_android_ident)
1658                     is_note_header = true;
1659 
1660                 if (is_note_header)
1661                 {
1662                     // Allow notes to refine module info.
1663                     DataExtractor data;
1664                     if (section_size && (data.SetData (object_data, sheader.sh_offset, section_size) == section_size))
1665                     {
1666                         Error error = RefineModuleDetailsFromNote (data, arch_spec, uuid);
1667                         if (error.Fail ())
1668                         {
1669                             if (log)
1670                                 log->Printf ("ObjectFileELF::%s ELF note processing failed: %s", __FUNCTION__, error.AsCString ());
1671                         }
1672                     }
1673                 }
1674             }
1675 
1676             // Make any unknown triple components to be unspecified unknowns.
1677             if (arch_spec.GetTriple().getVendor() == llvm::Triple::UnknownVendor)
1678                 arch_spec.GetTriple().setVendorName (llvm::StringRef());
1679             if (arch_spec.GetTriple().getOS() == llvm::Triple::UnknownOS)
1680                 arch_spec.GetTriple().setOSName (llvm::StringRef());
1681 
1682             return section_headers.size();
1683         }
1684     }
1685 
1686     section_headers.clear();
1687     return 0;
1688 }
1689 
1690 size_t
1691 ObjectFileELF::GetProgramHeaderCount()
1692 {
1693     return ParseProgramHeaders();
1694 }
1695 
1696 const elf::ELFProgramHeader *
1697 ObjectFileELF::GetProgramHeaderByIndex(lldb::user_id_t id)
1698 {
1699     if (!id || !ParseProgramHeaders())
1700         return NULL;
1701 
1702     if (--id < m_program_headers.size())
1703         return &m_program_headers[id];
1704 
1705     return NULL;
1706 }
1707 
1708 DataExtractor
1709 ObjectFileELF::GetSegmentDataByIndex(lldb::user_id_t id)
1710 {
1711     const elf::ELFProgramHeader *segment_header = GetProgramHeaderByIndex(id);
1712     if (segment_header == NULL)
1713         return DataExtractor();
1714     return DataExtractor(m_data, segment_header->p_offset, segment_header->p_filesz);
1715 }
1716 
1717 std::string
1718 ObjectFileELF::StripLinkerSymbolAnnotations(llvm::StringRef symbol_name) const
1719 {
1720     size_t pos = symbol_name.find('@');
1721     return symbol_name.substr(0, pos).str();
1722 }
1723 
1724 //----------------------------------------------------------------------
1725 // ParseSectionHeaders
1726 //----------------------------------------------------------------------
1727 size_t
1728 ObjectFileELF::ParseSectionHeaders()
1729 {
1730     return GetSectionHeaderInfo(m_section_headers, m_data, m_header, m_uuid, m_gnu_debuglink_file, m_gnu_debuglink_crc, m_arch_spec);
1731 }
1732 
1733 const ObjectFileELF::ELFSectionHeaderInfo *
1734 ObjectFileELF::GetSectionHeaderByIndex(lldb::user_id_t id)
1735 {
1736     if (!id || !ParseSectionHeaders())
1737         return NULL;
1738 
1739     if (--id < m_section_headers.size())
1740         return &m_section_headers[id];
1741 
1742     return NULL;
1743 }
1744 
1745 lldb::user_id_t
1746 ObjectFileELF::GetSectionIndexByName(const char* name)
1747 {
1748     if (!name || !name[0] || !ParseSectionHeaders())
1749         return 0;
1750     for (size_t i = 1; i < m_section_headers.size(); ++i)
1751         if (m_section_headers[i].section_name == ConstString(name))
1752             return i;
1753     return 0;
1754 }
1755 
1756 void
1757 ObjectFileELF::CreateSections(SectionList &unified_section_list)
1758 {
1759     if (!m_sections_ap.get() && ParseSectionHeaders())
1760     {
1761         m_sections_ap.reset(new SectionList());
1762 
1763         for (SectionHeaderCollIter I = m_section_headers.begin();
1764              I != m_section_headers.end(); ++I)
1765         {
1766             const ELFSectionHeaderInfo &header = *I;
1767 
1768             ConstString& name = I->section_name;
1769             const uint64_t file_size = header.sh_type == SHT_NOBITS ? 0 : header.sh_size;
1770             const uint64_t vm_size = header.sh_flags & SHF_ALLOC ? header.sh_size : 0;
1771 
1772             static ConstString g_sect_name_text (".text");
1773             static ConstString g_sect_name_data (".data");
1774             static ConstString g_sect_name_bss (".bss");
1775             static ConstString g_sect_name_tdata (".tdata");
1776             static ConstString g_sect_name_tbss (".tbss");
1777             static ConstString g_sect_name_dwarf_debug_abbrev (".debug_abbrev");
1778             static ConstString g_sect_name_dwarf_debug_addr (".debug_addr");
1779             static ConstString g_sect_name_dwarf_debug_aranges (".debug_aranges");
1780             static ConstString g_sect_name_dwarf_debug_frame (".debug_frame");
1781             static ConstString g_sect_name_dwarf_debug_info (".debug_info");
1782             static ConstString g_sect_name_dwarf_debug_line (".debug_line");
1783             static ConstString g_sect_name_dwarf_debug_loc (".debug_loc");
1784             static ConstString g_sect_name_dwarf_debug_macinfo (".debug_macinfo");
1785             static ConstString g_sect_name_dwarf_debug_macro (".debug_macro");
1786             static ConstString g_sect_name_dwarf_debug_pubnames (".debug_pubnames");
1787             static ConstString g_sect_name_dwarf_debug_pubtypes (".debug_pubtypes");
1788             static ConstString g_sect_name_dwarf_debug_ranges (".debug_ranges");
1789             static ConstString g_sect_name_dwarf_debug_str (".debug_str");
1790             static ConstString g_sect_name_dwarf_debug_str_offsets (".debug_str_offsets");
1791             static ConstString g_sect_name_dwarf_debug_abbrev_dwo (".debug_abbrev.dwo");
1792             static ConstString g_sect_name_dwarf_debug_info_dwo (".debug_info.dwo");
1793             static ConstString g_sect_name_dwarf_debug_line_dwo (".debug_line.dwo");
1794             static ConstString g_sect_name_dwarf_debug_macro_dwo (".debug_macro.dwo");
1795             static ConstString g_sect_name_dwarf_debug_loc_dwo (".debug_loc.dwo");
1796             static ConstString g_sect_name_dwarf_debug_str_dwo (".debug_str.dwo");
1797             static ConstString g_sect_name_dwarf_debug_str_offsets_dwo (".debug_str_offsets.dwo");
1798             static ConstString g_sect_name_eh_frame (".eh_frame");
1799             static ConstString g_sect_name_arm_exidx (".ARM.exidx");
1800             static ConstString g_sect_name_arm_extab (".ARM.extab");
1801             static ConstString g_sect_name_go_symtab (".gosymtab");
1802 
1803             SectionType sect_type = eSectionTypeOther;
1804 
1805             bool is_thread_specific = false;
1806 
1807             if      (name == g_sect_name_text)                  sect_type = eSectionTypeCode;
1808             else if (name == g_sect_name_data)                  sect_type = eSectionTypeData;
1809             else if (name == g_sect_name_bss)                   sect_type = eSectionTypeZeroFill;
1810             else if (name == g_sect_name_tdata)
1811             {
1812                 sect_type = eSectionTypeData;
1813                 is_thread_specific = true;
1814             }
1815             else if (name == g_sect_name_tbss)
1816             {
1817                 sect_type = eSectionTypeZeroFill;
1818                 is_thread_specific = true;
1819             }
1820             // .debug_abbrev – Abbreviations used in the .debug_info section
1821             // .debug_aranges – Lookup table for mapping addresses to compilation units
1822             // .debug_frame – Call frame information
1823             // .debug_info – The core DWARF information section
1824             // .debug_line – Line number information
1825             // .debug_loc – Location lists used in DW_AT_location attributes
1826             // .debug_macinfo – Macro information
1827             // .debug_pubnames – Lookup table for mapping object and function names to compilation units
1828             // .debug_pubtypes – Lookup table for mapping type names to compilation units
1829             // .debug_ranges – Address ranges used in DW_AT_ranges attributes
1830             // .debug_str – String table used in .debug_info
1831             // MISSING? .gnu_debugdata - "mini debuginfo / MiniDebugInfo" section, http://sourceware.org/gdb/onlinedocs/gdb/MiniDebugInfo.html
1832             // MISSING? .debug-index - http://src.chromium.org/viewvc/chrome/trunk/src/build/gdb-add-index?pathrev=144644
1833             // MISSING? .debug_types - Type descriptions from DWARF 4? See http://gcc.gnu.org/wiki/DwarfSeparateTypeInfo
1834             else if (name == g_sect_name_dwarf_debug_abbrev)          sect_type = eSectionTypeDWARFDebugAbbrev;
1835             else if (name == g_sect_name_dwarf_debug_addr)            sect_type = eSectionTypeDWARFDebugAddr;
1836             else if (name == g_sect_name_dwarf_debug_aranges)         sect_type = eSectionTypeDWARFDebugAranges;
1837             else if (name == g_sect_name_dwarf_debug_frame)           sect_type = eSectionTypeDWARFDebugFrame;
1838             else if (name == g_sect_name_dwarf_debug_info)            sect_type = eSectionTypeDWARFDebugInfo;
1839             else if (name == g_sect_name_dwarf_debug_line)            sect_type = eSectionTypeDWARFDebugLine;
1840             else if (name == g_sect_name_dwarf_debug_loc)             sect_type = eSectionTypeDWARFDebugLoc;
1841             else if (name == g_sect_name_dwarf_debug_macinfo)         sect_type = eSectionTypeDWARFDebugMacInfo;
1842             else if (name == g_sect_name_dwarf_debug_macro)           sect_type = eSectionTypeDWARFDebugMacro;
1843             else if (name == g_sect_name_dwarf_debug_pubnames)        sect_type = eSectionTypeDWARFDebugPubNames;
1844             else if (name == g_sect_name_dwarf_debug_pubtypes)        sect_type = eSectionTypeDWARFDebugPubTypes;
1845             else if (name == g_sect_name_dwarf_debug_ranges)          sect_type = eSectionTypeDWARFDebugRanges;
1846             else if (name == g_sect_name_dwarf_debug_str)             sect_type = eSectionTypeDWARFDebugStr;
1847             else if (name == g_sect_name_dwarf_debug_str_offsets)     sect_type = eSectionTypeDWARFDebugStrOffsets;
1848             else if (name == g_sect_name_dwarf_debug_abbrev_dwo)      sect_type = eSectionTypeDWARFDebugAbbrev;
1849             else if (name == g_sect_name_dwarf_debug_info_dwo)        sect_type = eSectionTypeDWARFDebugInfo;
1850             else if (name == g_sect_name_dwarf_debug_line_dwo)        sect_type = eSectionTypeDWARFDebugLine;
1851             else if (name == g_sect_name_dwarf_debug_macro_dwo)       sect_type = eSectionTypeDWARFDebugMacro;
1852             else if (name == g_sect_name_dwarf_debug_loc_dwo)         sect_type = eSectionTypeDWARFDebugLoc;
1853             else if (name == g_sect_name_dwarf_debug_str_dwo)         sect_type = eSectionTypeDWARFDebugStr;
1854             else if (name == g_sect_name_dwarf_debug_str_offsets_dwo) sect_type = eSectionTypeDWARFDebugStrOffsets;
1855             else if (name == g_sect_name_eh_frame)                    sect_type = eSectionTypeEHFrame;
1856             else if (name == g_sect_name_arm_exidx)                   sect_type = eSectionTypeARMexidx;
1857             else if (name == g_sect_name_arm_extab)                   sect_type = eSectionTypeARMextab;
1858             else if (name == g_sect_name_go_symtab)                   sect_type = eSectionTypeGoSymtab;
1859 
1860             switch (header.sh_type)
1861             {
1862                 case SHT_SYMTAB:
1863                     assert (sect_type == eSectionTypeOther);
1864                     sect_type = eSectionTypeELFSymbolTable;
1865                     break;
1866                 case SHT_DYNSYM:
1867                     assert (sect_type == eSectionTypeOther);
1868                     sect_type = eSectionTypeELFDynamicSymbols;
1869                     break;
1870                 case SHT_RELA:
1871                 case SHT_REL:
1872                     assert (sect_type == eSectionTypeOther);
1873                     sect_type = eSectionTypeELFRelocationEntries;
1874                     break;
1875                 case SHT_DYNAMIC:
1876                     assert (sect_type == eSectionTypeOther);
1877                     sect_type = eSectionTypeELFDynamicLinkInfo;
1878                     break;
1879             }
1880 
1881             if (eSectionTypeOther == sect_type)
1882             {
1883                 // the kalimba toolchain assumes that ELF section names are free-form. It does
1884                 // support linkscripts which (can) give rise to various arbitrarily named
1885                 // sections being "Code" or "Data".
1886                 sect_type = kalimbaSectionType(m_header, header);
1887             }
1888 
1889             const uint32_t target_bytes_size =
1890                 (eSectionTypeData == sect_type || eSectionTypeZeroFill == sect_type) ?
1891                 m_arch_spec.GetDataByteSize() :
1892                     eSectionTypeCode == sect_type ?
1893                     m_arch_spec.GetCodeByteSize() : 1;
1894 
1895             elf::elf_xword log2align = (header.sh_addralign==0)
1896                                         ? 0
1897                                         : llvm::Log2_64(header.sh_addralign);
1898             SectionSP section_sp (new Section(GetModule(),        // Module to which this section belongs.
1899                                               this,               // ObjectFile to which this section belongs and should read section data from.
1900                                               SectionIndex(I),    // Section ID.
1901                                               name,               // Section name.
1902                                               sect_type,          // Section type.
1903                                               header.sh_addr,     // VM address.
1904                                               vm_size,            // VM size in bytes of this section.
1905                                               header.sh_offset,   // Offset of this section in the file.
1906                                               file_size,          // Size of the section as found in the file.
1907                                               log2align,          // Alignment of the section
1908                                               header.sh_flags,    // Flags for this section.
1909                                               target_bytes_size));// Number of host bytes per target byte
1910 
1911             if (is_thread_specific)
1912                 section_sp->SetIsThreadSpecific (is_thread_specific);
1913             m_sections_ap->AddSection(section_sp);
1914         }
1915     }
1916 
1917     if (m_sections_ap.get())
1918     {
1919         if (GetType() == eTypeDebugInfo)
1920         {
1921             static const SectionType g_sections[] =
1922             {
1923                 eSectionTypeDWARFDebugAbbrev,
1924                 eSectionTypeDWARFDebugAddr,
1925                 eSectionTypeDWARFDebugAranges,
1926                 eSectionTypeDWARFDebugFrame,
1927                 eSectionTypeDWARFDebugInfo,
1928                 eSectionTypeDWARFDebugLine,
1929                 eSectionTypeDWARFDebugLoc,
1930                 eSectionTypeDWARFDebugMacInfo,
1931                 eSectionTypeDWARFDebugPubNames,
1932                 eSectionTypeDWARFDebugPubTypes,
1933                 eSectionTypeDWARFDebugRanges,
1934                 eSectionTypeDWARFDebugStr,
1935                 eSectionTypeDWARFDebugStrOffsets,
1936                 eSectionTypeELFSymbolTable,
1937             };
1938             SectionList *elf_section_list = m_sections_ap.get();
1939             for (size_t idx = 0; idx < sizeof(g_sections) / sizeof(g_sections[0]); ++idx)
1940             {
1941                 SectionType section_type = g_sections[idx];
1942                 SectionSP section_sp (elf_section_list->FindSectionByType (section_type, true));
1943                 if (section_sp)
1944                 {
1945                     SectionSP module_section_sp (unified_section_list.FindSectionByType (section_type, true));
1946                     if (module_section_sp)
1947                         unified_section_list.ReplaceSection (module_section_sp->GetID(), section_sp);
1948                     else
1949                         unified_section_list.AddSection (section_sp);
1950                 }
1951             }
1952         }
1953         else
1954         {
1955             unified_section_list = *m_sections_ap;
1956         }
1957     }
1958 }
1959 
1960 // Find the arm/aarch64 mapping symbol character in the given symbol name. Mapping symbols have the
1961 // form of "$<char>[.<any>]*". Additionally we recognize cases when the mapping symbol prefixed by
1962 // an arbitrary string because if a symbol prefix added to each symbol in the object file with
1963 // objcopy then the mapping symbols are also prefixed.
1964 static char
1965 FindArmAarch64MappingSymbol(const char* symbol_name)
1966 {
1967     if (!symbol_name)
1968         return '\0';
1969 
1970     const char* dollar_pos = ::strchr(symbol_name, '$');
1971     if (!dollar_pos || dollar_pos[1] == '\0')
1972         return '\0';
1973 
1974     if (dollar_pos[2] == '\0' || dollar_pos[2] == '.')
1975         return dollar_pos[1];
1976     return '\0';
1977 }
1978 
1979 #define STO_MIPS_ISA            (3 << 6)
1980 #define STO_MICROMIPS           (2 << 6)
1981 #define IS_MICROMIPS(ST_OTHER)  (((ST_OTHER) & STO_MIPS_ISA) == STO_MICROMIPS)
1982 
1983 // private
1984 unsigned
1985 ObjectFileELF::ParseSymbols (Symtab *symtab,
1986                              user_id_t start_id,
1987                              SectionList *section_list,
1988                              const size_t num_symbols,
1989                              const DataExtractor &symtab_data,
1990                              const DataExtractor &strtab_data)
1991 {
1992     ELFSymbol symbol;
1993     lldb::offset_t offset = 0;
1994 
1995     static ConstString text_section_name(".text");
1996     static ConstString init_section_name(".init");
1997     static ConstString fini_section_name(".fini");
1998     static ConstString ctors_section_name(".ctors");
1999     static ConstString dtors_section_name(".dtors");
2000 
2001     static ConstString data_section_name(".data");
2002     static ConstString rodata_section_name(".rodata");
2003     static ConstString rodata1_section_name(".rodata1");
2004     static ConstString data2_section_name(".data1");
2005     static ConstString bss_section_name(".bss");
2006     static ConstString opd_section_name(".opd");    // For ppc64
2007 
2008     // On Android the oatdata and the oatexec symbols in system@[email protected] covers the full
2009     // .text section what causes issues with displaying unusable symbol name to the user and very
2010     // slow unwinding speed because the instruction emulation based unwind plans try to emulate all
2011     // instructions in these symbols. Don't add these symbols to the symbol list as they have no
2012     // use for the debugger and they are causing a lot of trouble.
2013     // Filtering can't be restricted to Android because this special object file don't contain the
2014     // note section specifying the environment to Android but the custom extension and file name
2015     // makes it highly unlikely that this will collide with anything else.
2016     bool skip_oatdata_oatexec = m_file.GetFilename() == ConstString("system@[email protected]");
2017 
2018     ArchSpec arch;
2019     GetArchitecture(arch);
2020 
2021     // Local cache to avoid doing a FindSectionByName for each symbol. The "const char*" key must
2022     // came from a ConstString object so they can be compared by pointer
2023     std::unordered_map<const char*, lldb::SectionSP> section_name_to_section;
2024 
2025     unsigned i;
2026     for (i = 0; i < num_symbols; ++i)
2027     {
2028         if (symbol.Parse(symtab_data, &offset) == false)
2029             break;
2030 
2031         const char *symbol_name = strtab_data.PeekCStr(symbol.st_name);
2032 
2033         // No need to add non-section symbols that have no names
2034         if (symbol.getType() != STT_SECTION &&
2035             (symbol_name == NULL || symbol_name[0] == '\0'))
2036             continue;
2037 
2038         // Skipping oatdata and oatexec sections if it is requested. See details above the
2039         // definition of skip_oatdata_oatexec for the reasons.
2040         if (skip_oatdata_oatexec && (::strcmp(symbol_name, "oatdata") == 0 || ::strcmp(symbol_name, "oatexec") == 0))
2041             continue;
2042 
2043         SectionSP symbol_section_sp;
2044         SymbolType symbol_type = eSymbolTypeInvalid;
2045         Elf64_Half symbol_idx = symbol.st_shndx;
2046 
2047         switch (symbol_idx)
2048         {
2049         case SHN_ABS:
2050             symbol_type = eSymbolTypeAbsolute;
2051             break;
2052         case SHN_UNDEF:
2053             symbol_type = eSymbolTypeUndefined;
2054             break;
2055         default:
2056             symbol_section_sp = section_list->GetSectionAtIndex(symbol_idx);
2057             break;
2058         }
2059 
2060         // If a symbol is undefined do not process it further even if it has a STT type
2061         if (symbol_type != eSymbolTypeUndefined)
2062         {
2063             switch (symbol.getType())
2064             {
2065             default:
2066             case STT_NOTYPE:
2067                 // The symbol's type is not specified.
2068                 break;
2069 
2070             case STT_OBJECT:
2071                 // The symbol is associated with a data object, such as a variable,
2072                 // an array, etc.
2073                 symbol_type = eSymbolTypeData;
2074                 break;
2075 
2076             case STT_FUNC:
2077                 // The symbol is associated with a function or other executable code.
2078                 symbol_type = eSymbolTypeCode;
2079                 break;
2080 
2081             case STT_SECTION:
2082                 // The symbol is associated with a section. Symbol table entries of
2083                 // this type exist primarily for relocation and normally have
2084                 // STB_LOCAL binding.
2085                 break;
2086 
2087             case STT_FILE:
2088                 // Conventionally, the symbol's name gives the name of the source
2089                 // file associated with the object file. A file symbol has STB_LOCAL
2090                 // binding, its section index is SHN_ABS, and it precedes the other
2091                 // STB_LOCAL symbols for the file, if it is present.
2092                 symbol_type = eSymbolTypeSourceFile;
2093                 break;
2094 
2095             case STT_GNU_IFUNC:
2096                 // The symbol is associated with an indirect function. The actual
2097                 // function will be resolved if it is referenced.
2098                 symbol_type = eSymbolTypeResolver;
2099                 break;
2100             }
2101         }
2102 
2103         if (symbol_type == eSymbolTypeInvalid)
2104         {
2105             if (symbol_section_sp)
2106             {
2107                 const ConstString &sect_name = symbol_section_sp->GetName();
2108                 if (sect_name == text_section_name ||
2109                     sect_name == init_section_name ||
2110                     sect_name == fini_section_name ||
2111                     sect_name == ctors_section_name ||
2112                     sect_name == dtors_section_name)
2113                 {
2114                     symbol_type = eSymbolTypeCode;
2115                 }
2116                 else if (sect_name == data_section_name ||
2117                          sect_name == data2_section_name ||
2118                          sect_name == rodata_section_name ||
2119                          sect_name == rodata1_section_name ||
2120                          sect_name == bss_section_name)
2121                 {
2122                     symbol_type = eSymbolTypeData;
2123                 }
2124             }
2125         }
2126 
2127         int64_t symbol_value_offset = 0;
2128         uint32_t additional_flags = 0;
2129 
2130         if (arch.IsValid())
2131         {
2132             if (arch.GetMachine() == llvm::Triple::arm)
2133             {
2134                 if (symbol.getBinding() == STB_LOCAL)
2135                 {
2136                     char mapping_symbol = FindArmAarch64MappingSymbol(symbol_name);
2137                     if (symbol_type == eSymbolTypeCode)
2138                     {
2139                         switch (mapping_symbol)
2140                         {
2141                             case 'a':
2142                                 // $a[.<any>]* - marks an ARM instruction sequence
2143                                 m_address_class_map[symbol.st_value] = eAddressClassCode;
2144                                 break;
2145                             case 'b':
2146                             case 't':
2147                                 // $b[.<any>]* - marks a THUMB BL instruction sequence
2148                                 // $t[.<any>]* - marks a THUMB instruction sequence
2149                                 m_address_class_map[symbol.st_value] = eAddressClassCodeAlternateISA;
2150                                 break;
2151                             case 'd':
2152                                 // $d[.<any>]* - marks a data item sequence (e.g. lit pool)
2153                                 m_address_class_map[symbol.st_value] = eAddressClassData;
2154                                 break;
2155                         }
2156                     }
2157                     if (mapping_symbol)
2158                         continue;
2159                 }
2160             }
2161             else if (arch.GetMachine() == llvm::Triple::aarch64)
2162             {
2163                 if (symbol.getBinding() == STB_LOCAL)
2164                 {
2165                     char mapping_symbol = FindArmAarch64MappingSymbol(symbol_name);
2166                     if (symbol_type == eSymbolTypeCode)
2167                     {
2168                         switch (mapping_symbol)
2169                         {
2170                             case 'x':
2171                                 // $x[.<any>]* - marks an A64 instruction sequence
2172                                 m_address_class_map[symbol.st_value] = eAddressClassCode;
2173                                 break;
2174                             case 'd':
2175                                 // $d[.<any>]* - marks a data item sequence (e.g. lit pool)
2176                                 m_address_class_map[symbol.st_value] = eAddressClassData;
2177                                 break;
2178                         }
2179                     }
2180                     if (mapping_symbol)
2181                         continue;
2182                 }
2183             }
2184 
2185             if (arch.GetMachine() == llvm::Triple::arm)
2186             {
2187                 if (symbol_type == eSymbolTypeCode)
2188                 {
2189                     if (symbol.st_value & 1)
2190                     {
2191                         // Subtracting 1 from the address effectively unsets
2192                         // the low order bit, which results in the address
2193                         // actually pointing to the beginning of the symbol.
2194                         // This delta will be used below in conjunction with
2195                         // symbol.st_value to produce the final symbol_value
2196                         // that we store in the symtab.
2197                         symbol_value_offset = -1;
2198                         additional_flags = ARM_ELF_SYM_IS_THUMB;
2199                         m_address_class_map[symbol.st_value^1] = eAddressClassCodeAlternateISA;
2200                     }
2201                     else
2202                     {
2203                         // This address is ARM
2204                         m_address_class_map[symbol.st_value] = eAddressClassCode;
2205                     }
2206                 }
2207             }
2208 
2209             /*
2210              * MIPS:
2211              * The bit #0 of an address is used for ISA mode (1 for microMIPS, 0 for MIPS).
2212              * This allows processer to switch between microMIPS and MIPS without any need
2213              * for special mode-control register. However, apart from .debug_line, none of
2214              * the ELF/DWARF sections set the ISA bit (for symbol or section). Use st_other
2215              * flag to check whether the symbol is microMIPS and then set the address class
2216              * accordingly.
2217             */
2218             const llvm::Triple::ArchType llvm_arch = arch.GetMachine();
2219             if (llvm_arch == llvm::Triple::mips || llvm_arch == llvm::Triple::mipsel
2220                 || llvm_arch == llvm::Triple::mips64 || llvm_arch == llvm::Triple::mips64el)
2221             {
2222                 if (IS_MICROMIPS(symbol.st_other))
2223                     m_address_class_map[symbol.st_value] = eAddressClassCodeAlternateISA;
2224                 else if ((symbol.st_value & 1) && (symbol_type == eSymbolTypeCode))
2225                 {
2226                     symbol.st_value = symbol.st_value & (~1ull);
2227                     m_address_class_map[symbol.st_value] = eAddressClassCodeAlternateISA;
2228                 }
2229                 else
2230                 {
2231                     if (symbol_type == eSymbolTypeCode)
2232                         m_address_class_map[symbol.st_value] = eAddressClassCode;
2233                     else if (symbol_type == eSymbolTypeData)
2234                         m_address_class_map[symbol.st_value] = eAddressClassData;
2235                     else
2236                         m_address_class_map[symbol.st_value] = eAddressClassUnknown;
2237                 }
2238             }
2239         }
2240 
2241         // symbol_value_offset may contain 0 for ARM symbols or -1 for
2242         // THUMB symbols. See above for more details.
2243         uint64_t symbol_value = symbol.st_value + symbol_value_offset;
2244         if (symbol_section_sp && CalculateType() != ObjectFile::Type::eTypeObjectFile)
2245             symbol_value -= symbol_section_sp->GetFileAddress();
2246 
2247         if (symbol_section_sp)
2248         {
2249             ModuleSP module_sp(GetModule());
2250             if (module_sp)
2251             {
2252                 SectionList *module_section_list = module_sp->GetSectionList();
2253                 if (module_section_list && module_section_list != section_list)
2254                 {
2255                     const ConstString &sect_name = symbol_section_sp->GetName();
2256                     auto section_it = section_name_to_section.find(sect_name.GetCString());
2257                     if (section_it == section_name_to_section.end())
2258                         section_it = section_name_to_section.emplace(
2259                             sect_name.GetCString(),
2260                             module_section_list->FindSectionByName (sect_name)).first;
2261                     if (section_it->second && section_it->second->GetFileSize())
2262                         symbol_section_sp = section_it->second;
2263                 }
2264             }
2265         }
2266 
2267         bool is_global = symbol.getBinding() == STB_GLOBAL;
2268         uint32_t flags = symbol.st_other << 8 | symbol.st_info | additional_flags;
2269         bool is_mangled = symbol_name ? (symbol_name[0] == '_' && symbol_name[1] == 'Z') : false;
2270 
2271         llvm::StringRef symbol_ref(symbol_name);
2272 
2273         // Symbol names may contain @VERSION suffixes. Find those and strip them temporarily.
2274         size_t version_pos = symbol_ref.find('@');
2275         bool has_suffix = version_pos != llvm::StringRef::npos;
2276         llvm::StringRef symbol_bare = symbol_ref.substr(0, version_pos);
2277         Mangled mangled(ConstString(symbol_bare), is_mangled);
2278 
2279         // Now append the suffix back to mangled and unmangled names. Only do it if the
2280         // demangling was successful (string is not empty).
2281         if (has_suffix)
2282         {
2283             llvm::StringRef suffix = symbol_ref.substr(version_pos);
2284 
2285             llvm::StringRef mangled_name = mangled.GetMangledName().GetStringRef();
2286             if (! mangled_name.empty())
2287                 mangled.SetMangledName( ConstString((mangled_name + suffix).str()) );
2288 
2289             ConstString demangled = mangled.GetDemangledName(lldb::eLanguageTypeUnknown);
2290             llvm::StringRef demangled_name = demangled.GetStringRef();
2291             if (!demangled_name.empty())
2292                 mangled.SetDemangledName( ConstString((demangled_name + suffix).str()) );
2293         }
2294 
2295         Symbol dc_symbol(
2296             i + start_id,       // ID is the original symbol table index.
2297             mangled,
2298             symbol_type,        // Type of this symbol
2299             is_global,          // Is this globally visible?
2300             false,              // Is this symbol debug info?
2301             false,              // Is this symbol a trampoline?
2302             false,              // Is this symbol artificial?
2303             AddressRange(
2304                 symbol_section_sp,  // Section in which this symbol is defined or null.
2305                 symbol_value,       // Offset in section or symbol value.
2306                 symbol.st_size),    // Size in bytes of this symbol.
2307             symbol.st_size != 0,    // Size is valid if it is not 0
2308             has_suffix,             // Contains linker annotations?
2309             flags);                 // Symbol flags.
2310         symtab->AddSymbol(dc_symbol);
2311     }
2312     return i;
2313 }
2314 
2315 unsigned
2316 ObjectFileELF::ParseSymbolTable(Symtab *symbol_table, user_id_t start_id, lldb_private::Section *symtab)
2317 {
2318     if (symtab->GetObjectFile() != this)
2319     {
2320         // If the symbol table section is owned by a different object file, have it do the
2321         // parsing.
2322         ObjectFileELF *obj_file_elf = static_cast<ObjectFileELF *>(symtab->GetObjectFile());
2323         return obj_file_elf->ParseSymbolTable (symbol_table, start_id, symtab);
2324     }
2325 
2326     // Get section list for this object file.
2327     SectionList *section_list = m_sections_ap.get();
2328     if (!section_list)
2329         return 0;
2330 
2331     user_id_t symtab_id = symtab->GetID();
2332     const ELFSectionHeaderInfo *symtab_hdr = GetSectionHeaderByIndex(symtab_id);
2333     assert(symtab_hdr->sh_type == SHT_SYMTAB ||
2334            symtab_hdr->sh_type == SHT_DYNSYM);
2335 
2336     // sh_link: section header index of associated string table.
2337     // Section ID's are ones based.
2338     user_id_t strtab_id = symtab_hdr->sh_link + 1;
2339     Section *strtab = section_list->FindSectionByID(strtab_id).get();
2340 
2341     if (symtab && strtab)
2342     {
2343         assert (symtab->GetObjectFile() == this);
2344         assert (strtab->GetObjectFile() == this);
2345 
2346         DataExtractor symtab_data;
2347         DataExtractor strtab_data;
2348         if (ReadSectionData(symtab, symtab_data) &&
2349             ReadSectionData(strtab, strtab_data))
2350         {
2351             size_t num_symbols = symtab_data.GetByteSize() / symtab_hdr->sh_entsize;
2352 
2353             return ParseSymbols(symbol_table, start_id, section_list,
2354                                 num_symbols, symtab_data, strtab_data);
2355         }
2356     }
2357 
2358     return 0;
2359 }
2360 
2361 size_t
2362 ObjectFileELF::ParseDynamicSymbols()
2363 {
2364     if (m_dynamic_symbols.size())
2365         return m_dynamic_symbols.size();
2366 
2367     SectionList *section_list = GetSectionList();
2368     if (!section_list)
2369         return 0;
2370 
2371     // Find the SHT_DYNAMIC section.
2372     Section *dynsym = section_list->FindSectionByType (eSectionTypeELFDynamicLinkInfo, true).get();
2373     if (!dynsym)
2374         return 0;
2375     assert (dynsym->GetObjectFile() == this);
2376 
2377     ELFDynamic symbol;
2378     DataExtractor dynsym_data;
2379     if (ReadSectionData(dynsym, dynsym_data))
2380     {
2381         const lldb::offset_t section_size = dynsym_data.GetByteSize();
2382         lldb::offset_t cursor = 0;
2383 
2384         while (cursor < section_size)
2385         {
2386             if (!symbol.Parse(dynsym_data, &cursor))
2387                 break;
2388 
2389             m_dynamic_symbols.push_back(symbol);
2390         }
2391     }
2392 
2393     return m_dynamic_symbols.size();
2394 }
2395 
2396 const ELFDynamic *
2397 ObjectFileELF::FindDynamicSymbol(unsigned tag)
2398 {
2399     if (!ParseDynamicSymbols())
2400         return NULL;
2401 
2402     DynamicSymbolCollIter I = m_dynamic_symbols.begin();
2403     DynamicSymbolCollIter E = m_dynamic_symbols.end();
2404     for ( ; I != E; ++I)
2405     {
2406         ELFDynamic *symbol = &*I;
2407 
2408         if (symbol->d_tag == tag)
2409             return symbol;
2410     }
2411 
2412     return NULL;
2413 }
2414 
2415 unsigned
2416 ObjectFileELF::PLTRelocationType()
2417 {
2418     // DT_PLTREL
2419     //  This member specifies the type of relocation entry to which the
2420     //  procedure linkage table refers. The d_val member holds DT_REL or
2421     //  DT_RELA, as appropriate. All relocations in a procedure linkage table
2422     //  must use the same relocation.
2423     const ELFDynamic *symbol = FindDynamicSymbol(DT_PLTREL);
2424 
2425     if (symbol)
2426         return symbol->d_val;
2427 
2428     return 0;
2429 }
2430 
2431 // Returns the size of the normal plt entries and the offset of the first normal plt entry. The
2432 // 0th entry in the plt table is usually a resolution entry which have different size in some
2433 // architectures then the rest of the plt entries.
2434 static std::pair<uint64_t, uint64_t>
2435 GetPltEntrySizeAndOffset(const ELFSectionHeader* rel_hdr, const ELFSectionHeader* plt_hdr)
2436 {
2437     const elf_xword num_relocations = rel_hdr->sh_size / rel_hdr->sh_entsize;
2438 
2439     // Clang 3.3 sets entsize to 4 for 32-bit binaries, but the plt entries are 16 bytes.
2440     // So round the entsize up by the alignment if addralign is set.
2441     elf_xword plt_entsize = plt_hdr->sh_addralign ?
2442         llvm::RoundUpToAlignment (plt_hdr->sh_entsize, plt_hdr->sh_addralign) : plt_hdr->sh_entsize;
2443 
2444     if (plt_entsize == 0)
2445     {
2446         // The linker haven't set the plt_hdr->sh_entsize field. Try to guess the size of the plt
2447         // entries based on the number of entries and the size of the plt section with the
2448         // assumption that the size of the 0th entry is at least as big as the size of the normal
2449         // entries and it isn't much bigger then that.
2450         if (plt_hdr->sh_addralign)
2451             plt_entsize = plt_hdr->sh_size / plt_hdr->sh_addralign / (num_relocations + 1) * plt_hdr->sh_addralign;
2452         else
2453             plt_entsize = plt_hdr->sh_size / (num_relocations + 1);
2454     }
2455 
2456     elf_xword plt_offset = plt_hdr->sh_size - num_relocations * plt_entsize;
2457 
2458     return std::make_pair(plt_entsize, plt_offset);
2459 }
2460 
2461 static unsigned
2462 ParsePLTRelocations(Symtab *symbol_table,
2463                     user_id_t start_id,
2464                     unsigned rel_type,
2465                     const ELFHeader *hdr,
2466                     const ELFSectionHeader *rel_hdr,
2467                     const ELFSectionHeader *plt_hdr,
2468                     const ELFSectionHeader *sym_hdr,
2469                     const lldb::SectionSP &plt_section_sp,
2470                     DataExtractor &rel_data,
2471                     DataExtractor &symtab_data,
2472                     DataExtractor &strtab_data)
2473 {
2474     ELFRelocation rel(rel_type);
2475     ELFSymbol symbol;
2476     lldb::offset_t offset = 0;
2477 
2478     uint64_t plt_offset, plt_entsize;
2479     std::tie(plt_entsize, plt_offset) = GetPltEntrySizeAndOffset(rel_hdr, plt_hdr);
2480     const elf_xword num_relocations = rel_hdr->sh_size / rel_hdr->sh_entsize;
2481 
2482     typedef unsigned (*reloc_info_fn)(const ELFRelocation &rel);
2483     reloc_info_fn reloc_type;
2484     reloc_info_fn reloc_symbol;
2485 
2486     if (hdr->Is32Bit())
2487     {
2488         reloc_type = ELFRelocation::RelocType32;
2489         reloc_symbol = ELFRelocation::RelocSymbol32;
2490     }
2491     else
2492     {
2493         reloc_type = ELFRelocation::RelocType64;
2494         reloc_symbol = ELFRelocation::RelocSymbol64;
2495     }
2496 
2497     unsigned slot_type = hdr->GetRelocationJumpSlotType();
2498     unsigned i;
2499     for (i = 0; i < num_relocations; ++i)
2500     {
2501         if (rel.Parse(rel_data, &offset) == false)
2502             break;
2503 
2504         if (reloc_type(rel) != slot_type)
2505             continue;
2506 
2507         lldb::offset_t symbol_offset = reloc_symbol(rel) * sym_hdr->sh_entsize;
2508         if (!symbol.Parse(symtab_data, &symbol_offset))
2509             break;
2510 
2511         const char *symbol_name = strtab_data.PeekCStr(symbol.st_name);
2512         bool is_mangled = symbol_name ? (symbol_name[0] == '_' && symbol_name[1] == 'Z') : false;
2513         uint64_t plt_index = plt_offset + i * plt_entsize;
2514 
2515         Symbol jump_symbol(
2516             i + start_id,    // Symbol table index
2517             symbol_name,     // symbol name.
2518             is_mangled,      // is the symbol name mangled?
2519             eSymbolTypeTrampoline, // Type of this symbol
2520             false,           // Is this globally visible?
2521             false,           // Is this symbol debug info?
2522             true,            // Is this symbol a trampoline?
2523             true,            // Is this symbol artificial?
2524             plt_section_sp,  // Section in which this symbol is defined or null.
2525             plt_index,       // Offset in section or symbol value.
2526             plt_entsize,     // Size in bytes of this symbol.
2527             true,            // Size is valid
2528             false,           // Contains linker annotations?
2529             0);              // Symbol flags.
2530 
2531         symbol_table->AddSymbol(jump_symbol);
2532     }
2533 
2534     return i;
2535 }
2536 
2537 unsigned
2538 ObjectFileELF::ParseTrampolineSymbols(Symtab *symbol_table,
2539                                       user_id_t start_id,
2540                                       const ELFSectionHeaderInfo *rel_hdr,
2541                                       user_id_t rel_id)
2542 {
2543     assert(rel_hdr->sh_type == SHT_RELA || rel_hdr->sh_type == SHT_REL);
2544 
2545     // The link field points to the associated symbol table. The info field
2546     // points to the section holding the plt.
2547     user_id_t symtab_id = rel_hdr->sh_link;
2548     user_id_t plt_id = rel_hdr->sh_info;
2549 
2550     // If the link field doesn't point to the appropriate symbol name table then
2551     // try to find it by name as some compiler don't fill in the link fields.
2552     if (!symtab_id)
2553         symtab_id = GetSectionIndexByName(".dynsym");
2554     if (!plt_id)
2555         plt_id = GetSectionIndexByName(".plt");
2556 
2557     if (!symtab_id || !plt_id)
2558         return 0;
2559 
2560     // Section ID's are ones based;
2561     symtab_id++;
2562     plt_id++;
2563 
2564     const ELFSectionHeaderInfo *plt_hdr = GetSectionHeaderByIndex(plt_id);
2565     if (!plt_hdr)
2566         return 0;
2567 
2568     const ELFSectionHeaderInfo *sym_hdr = GetSectionHeaderByIndex(symtab_id);
2569     if (!sym_hdr)
2570         return 0;
2571 
2572     SectionList *section_list = m_sections_ap.get();
2573     if (!section_list)
2574         return 0;
2575 
2576     Section *rel_section = section_list->FindSectionByID(rel_id).get();
2577     if (!rel_section)
2578         return 0;
2579 
2580     SectionSP plt_section_sp (section_list->FindSectionByID(plt_id));
2581     if (!plt_section_sp)
2582         return 0;
2583 
2584     Section *symtab = section_list->FindSectionByID(symtab_id).get();
2585     if (!symtab)
2586         return 0;
2587 
2588     // sh_link points to associated string table.
2589     Section *strtab = section_list->FindSectionByID(sym_hdr->sh_link + 1).get();
2590     if (!strtab)
2591         return 0;
2592 
2593     DataExtractor rel_data;
2594     if (!ReadSectionData(rel_section, rel_data))
2595         return 0;
2596 
2597     DataExtractor symtab_data;
2598     if (!ReadSectionData(symtab, symtab_data))
2599         return 0;
2600 
2601     DataExtractor strtab_data;
2602     if (!ReadSectionData(strtab, strtab_data))
2603         return 0;
2604 
2605     unsigned rel_type = PLTRelocationType();
2606     if (!rel_type)
2607         return 0;
2608 
2609     return ParsePLTRelocations (symbol_table,
2610                                 start_id,
2611                                 rel_type,
2612                                 &m_header,
2613                                 rel_hdr,
2614                                 plt_hdr,
2615                                 sym_hdr,
2616                                 plt_section_sp,
2617                                 rel_data,
2618                                 symtab_data,
2619                                 strtab_data);
2620 }
2621 
2622 unsigned
2623 ObjectFileELF::RelocateSection(Symtab* symtab, const ELFHeader *hdr, const ELFSectionHeader *rel_hdr,
2624                 const ELFSectionHeader *symtab_hdr, const ELFSectionHeader *debug_hdr,
2625                 DataExtractor &rel_data, DataExtractor &symtab_data,
2626                 DataExtractor &debug_data, Section* rel_section)
2627 {
2628     ELFRelocation rel(rel_hdr->sh_type);
2629     lldb::addr_t offset = 0;
2630     const unsigned num_relocations = rel_hdr->sh_size / rel_hdr->sh_entsize;
2631     typedef unsigned (*reloc_info_fn)(const ELFRelocation &rel);
2632     reloc_info_fn reloc_type;
2633     reloc_info_fn reloc_symbol;
2634 
2635     if (hdr->Is32Bit())
2636     {
2637         reloc_type = ELFRelocation::RelocType32;
2638         reloc_symbol = ELFRelocation::RelocSymbol32;
2639     }
2640     else
2641     {
2642         reloc_type = ELFRelocation::RelocType64;
2643         reloc_symbol = ELFRelocation::RelocSymbol64;
2644     }
2645 
2646     for (unsigned i = 0; i < num_relocations; ++i)
2647     {
2648         if (rel.Parse(rel_data, &offset) == false)
2649             break;
2650 
2651         Symbol* symbol = NULL;
2652 
2653         if (hdr->Is32Bit())
2654         {
2655             switch (reloc_type(rel)) {
2656             case R_386_32:
2657             case R_386_PC32:
2658             default:
2659                 assert(false && "unexpected relocation type");
2660             }
2661         } else {
2662             switch (reloc_type(rel)) {
2663             case R_X86_64_64:
2664             {
2665                 symbol = symtab->FindSymbolByID(reloc_symbol(rel));
2666                 if (symbol)
2667                 {
2668                     addr_t value = symbol->GetAddressRef().GetFileAddress();
2669                     DataBufferSP& data_buffer_sp = debug_data.GetSharedDataBuffer();
2670                     uint64_t* dst = reinterpret_cast<uint64_t*>(data_buffer_sp->GetBytes() + rel_section->GetFileOffset() + ELFRelocation::RelocOffset64(rel));
2671                     *dst = value + ELFRelocation::RelocAddend64(rel);
2672                 }
2673                 break;
2674             }
2675             case R_X86_64_32:
2676             case R_X86_64_32S:
2677             {
2678                 symbol = symtab->FindSymbolByID(reloc_symbol(rel));
2679                 if (symbol)
2680                 {
2681                     addr_t value = symbol->GetAddressRef().GetFileAddress();
2682                     value += ELFRelocation::RelocAddend32(rel);
2683                     assert((reloc_type(rel) == R_X86_64_32 && (value <= UINT32_MAX)) ||
2684                            (reloc_type(rel) == R_X86_64_32S &&
2685                             ((int64_t)value <= INT32_MAX && (int64_t)value >= INT32_MIN)));
2686                     uint32_t truncated_addr = (value & 0xFFFFFFFF);
2687                     DataBufferSP& data_buffer_sp = debug_data.GetSharedDataBuffer();
2688                     uint32_t* dst = reinterpret_cast<uint32_t*>(data_buffer_sp->GetBytes() + rel_section->GetFileOffset() + ELFRelocation::RelocOffset32(rel));
2689                     *dst = truncated_addr;
2690                 }
2691                 break;
2692             }
2693             case R_X86_64_PC32:
2694             default:
2695                 assert(false && "unexpected relocation type");
2696             }
2697         }
2698     }
2699 
2700     return 0;
2701 }
2702 
2703 unsigned
2704 ObjectFileELF::RelocateDebugSections(const ELFSectionHeader *rel_hdr, user_id_t rel_id)
2705 {
2706     assert(rel_hdr->sh_type == SHT_RELA || rel_hdr->sh_type == SHT_REL);
2707 
2708     // Parse in the section list if needed.
2709     SectionList *section_list = GetSectionList();
2710     if (!section_list)
2711         return 0;
2712 
2713     // Section ID's are ones based.
2714     user_id_t symtab_id = rel_hdr->sh_link + 1;
2715     user_id_t debug_id = rel_hdr->sh_info + 1;
2716 
2717     const ELFSectionHeader *symtab_hdr = GetSectionHeaderByIndex(symtab_id);
2718     if (!symtab_hdr)
2719         return 0;
2720 
2721     const ELFSectionHeader *debug_hdr = GetSectionHeaderByIndex(debug_id);
2722     if (!debug_hdr)
2723         return 0;
2724 
2725     Section *rel = section_list->FindSectionByID(rel_id).get();
2726     if (!rel)
2727         return 0;
2728 
2729     Section *symtab = section_list->FindSectionByID(symtab_id).get();
2730     if (!symtab)
2731         return 0;
2732 
2733     Section *debug = section_list->FindSectionByID(debug_id).get();
2734     if (!debug)
2735         return 0;
2736 
2737     DataExtractor rel_data;
2738     DataExtractor symtab_data;
2739     DataExtractor debug_data;
2740 
2741     if (ReadSectionData(rel, rel_data) &&
2742         ReadSectionData(symtab, symtab_data) &&
2743         ReadSectionData(debug, debug_data))
2744     {
2745         RelocateSection(m_symtab_ap.get(), &m_header, rel_hdr, symtab_hdr, debug_hdr,
2746                         rel_data, symtab_data, debug_data, debug);
2747     }
2748 
2749     return 0;
2750 }
2751 
2752 Symtab *
2753 ObjectFileELF::GetSymtab()
2754 {
2755     ModuleSP module_sp(GetModule());
2756     if (!module_sp)
2757         return NULL;
2758 
2759     // We always want to use the main object file so we (hopefully) only have one cached copy
2760     // of our symtab, dynamic sections, etc.
2761     ObjectFile *module_obj_file = module_sp->GetObjectFile();
2762     if (module_obj_file && module_obj_file != this)
2763         return module_obj_file->GetSymtab();
2764 
2765     if (m_symtab_ap.get() == NULL)
2766     {
2767         SectionList *section_list = module_sp->GetSectionList();
2768         if (!section_list)
2769             return NULL;
2770 
2771         uint64_t symbol_id = 0;
2772         lldb_private::Mutex::Locker locker(module_sp->GetMutex());
2773 
2774         // Sharable objects and dynamic executables usually have 2 distinct symbol
2775         // tables, one named ".symtab", and the other ".dynsym". The dynsym is a smaller
2776         // version of the symtab that only contains global symbols. The information found
2777         // in the dynsym is therefore also found in the symtab, while the reverse is not
2778         // necessarily true.
2779         Section *symtab = section_list->FindSectionByType (eSectionTypeELFSymbolTable, true).get();
2780         if (!symtab)
2781         {
2782             // The symtab section is non-allocable and can be stripped, so if it doesn't exist
2783             // then use the dynsym section which should always be there.
2784             symtab = section_list->FindSectionByType (eSectionTypeELFDynamicSymbols, true).get();
2785         }
2786         if (symtab)
2787         {
2788             m_symtab_ap.reset(new Symtab(symtab->GetObjectFile()));
2789             symbol_id += ParseSymbolTable (m_symtab_ap.get(), symbol_id, symtab);
2790         }
2791 
2792         // DT_JMPREL
2793         //      If present, this entry's d_ptr member holds the address of relocation
2794         //      entries associated solely with the procedure linkage table. Separating
2795         //      these relocation entries lets the dynamic linker ignore them during
2796         //      process initialization, if lazy binding is enabled. If this entry is
2797         //      present, the related entries of types DT_PLTRELSZ and DT_PLTREL must
2798         //      also be present.
2799         const ELFDynamic *symbol = FindDynamicSymbol(DT_JMPREL);
2800         if (symbol)
2801         {
2802             // Synthesize trampoline symbols to help navigate the PLT.
2803             addr_t addr = symbol->d_ptr;
2804             Section *reloc_section = section_list->FindSectionContainingFileAddress(addr).get();
2805             if (reloc_section)
2806             {
2807                 user_id_t reloc_id = reloc_section->GetID();
2808                 const ELFSectionHeaderInfo *reloc_header = GetSectionHeaderByIndex(reloc_id);
2809                 assert(reloc_header);
2810 
2811                 if (m_symtab_ap == nullptr)
2812                     m_symtab_ap.reset(new Symtab(reloc_section->GetObjectFile()));
2813 
2814                 ParseTrampolineSymbols (m_symtab_ap.get(), symbol_id, reloc_header, reloc_id);
2815             }
2816         }
2817 
2818         // If we still don't have any symtab then create an empty instance to avoid do the section
2819         // lookup next time.
2820         if (m_symtab_ap == nullptr)
2821             m_symtab_ap.reset(new Symtab(this));
2822 
2823         m_symtab_ap->CalculateSymbolSizes();
2824     }
2825 
2826     for (SectionHeaderCollIter I = m_section_headers.begin();
2827          I != m_section_headers.end(); ++I)
2828     {
2829         if (I->sh_type == SHT_RELA || I->sh_type == SHT_REL)
2830         {
2831             if (CalculateType() == eTypeObjectFile)
2832             {
2833                 const char *section_name = I->section_name.AsCString("");
2834                 if (strstr(section_name, ".rela.debug") ||
2835                     strstr(section_name, ".rel.debug"))
2836                 {
2837                     const ELFSectionHeader &reloc_header = *I;
2838                     user_id_t reloc_id = SectionIndex(I);
2839                     RelocateDebugSections(&reloc_header, reloc_id);
2840                 }
2841             }
2842         }
2843     }
2844     return m_symtab_ap.get();
2845 }
2846 
2847 Symbol *
2848 ObjectFileELF::ResolveSymbolForAddress(const Address& so_addr, bool verify_unique)
2849 {
2850     if (!m_symtab_ap.get())
2851         return nullptr; // GetSymtab() should be called first.
2852 
2853     const SectionList *section_list = GetSectionList();
2854     if (!section_list)
2855         return nullptr;
2856 
2857     if (DWARFCallFrameInfo *eh_frame = GetUnwindTable().GetEHFrameInfo())
2858     {
2859         AddressRange range;
2860         if (eh_frame->GetAddressRange (so_addr, range))
2861         {
2862             const addr_t file_addr = range.GetBaseAddress().GetFileAddress();
2863             Symbol * symbol = verify_unique ? m_symtab_ap->FindSymbolContainingFileAddress(file_addr) : nullptr;
2864             if (symbol)
2865                 return symbol;
2866 
2867             // Note that a (stripped) symbol won't be found by GetSymtab()...
2868             lldb::SectionSP eh_sym_section_sp = section_list->FindSectionContainingFileAddress(file_addr);
2869             if (eh_sym_section_sp.get())
2870             {
2871                 addr_t section_base = eh_sym_section_sp->GetFileAddress();
2872                 addr_t offset = file_addr - section_base;
2873                 uint64_t symbol_id = m_symtab_ap->GetNumSymbols();
2874 
2875                 Symbol eh_symbol(
2876                         symbol_id,            // Symbol table index.
2877                         "???",                // Symbol name.
2878                         false,                // Is the symbol name mangled?
2879                         eSymbolTypeCode,      // Type of this symbol.
2880                         true,                 // Is this globally visible?
2881                         false,                // Is this symbol debug info?
2882                         false,                // Is this symbol a trampoline?
2883                         true,                 // Is this symbol artificial?
2884                         eh_sym_section_sp,    // Section in which this symbol is defined or null.
2885                         offset,               // Offset in section or symbol value.
2886                         range.GetByteSize(),  // Size in bytes of this symbol.
2887                         true,                 // Size is valid.
2888                         false,                // Contains linker annotations?
2889                         0);                   // Symbol flags.
2890                 if (symbol_id == m_symtab_ap->AddSymbol(eh_symbol))
2891                     return m_symtab_ap->SymbolAtIndex(symbol_id);
2892             }
2893         }
2894     }
2895     return nullptr;
2896 }
2897 
2898 
2899 bool
2900 ObjectFileELF::IsStripped ()
2901 {
2902     // TODO: determine this for ELF
2903     return false;
2904 }
2905 
2906 //===----------------------------------------------------------------------===//
2907 // Dump
2908 //
2909 // Dump the specifics of the runtime file container (such as any headers
2910 // segments, sections, etc).
2911 //----------------------------------------------------------------------
2912 void
2913 ObjectFileELF::Dump(Stream *s)
2914 {
2915     DumpELFHeader(s, m_header);
2916     s->EOL();
2917     DumpELFProgramHeaders(s);
2918     s->EOL();
2919     DumpELFSectionHeaders(s);
2920     s->EOL();
2921     SectionList *section_list = GetSectionList();
2922     if (section_list)
2923         section_list->Dump(s, NULL, true, UINT32_MAX);
2924     Symtab *symtab = GetSymtab();
2925     if (symtab)
2926         symtab->Dump(s, NULL, eSortOrderNone);
2927     s->EOL();
2928     DumpDependentModules(s);
2929     s->EOL();
2930 }
2931 
2932 //----------------------------------------------------------------------
2933 // DumpELFHeader
2934 //
2935 // Dump the ELF header to the specified output stream
2936 //----------------------------------------------------------------------
2937 void
2938 ObjectFileELF::DumpELFHeader(Stream *s, const ELFHeader &header)
2939 {
2940     s->PutCString("ELF Header\n");
2941     s->Printf("e_ident[EI_MAG0   ] = 0x%2.2x\n", header.e_ident[EI_MAG0]);
2942     s->Printf("e_ident[EI_MAG1   ] = 0x%2.2x '%c'\n",
2943               header.e_ident[EI_MAG1], header.e_ident[EI_MAG1]);
2944     s->Printf("e_ident[EI_MAG2   ] = 0x%2.2x '%c'\n",
2945               header.e_ident[EI_MAG2], header.e_ident[EI_MAG2]);
2946     s->Printf("e_ident[EI_MAG3   ] = 0x%2.2x '%c'\n",
2947               header.e_ident[EI_MAG3], header.e_ident[EI_MAG3]);
2948 
2949     s->Printf("e_ident[EI_CLASS  ] = 0x%2.2x\n", header.e_ident[EI_CLASS]);
2950     s->Printf("e_ident[EI_DATA   ] = 0x%2.2x ", header.e_ident[EI_DATA]);
2951     DumpELFHeader_e_ident_EI_DATA(s, header.e_ident[EI_DATA]);
2952     s->Printf ("\ne_ident[EI_VERSION] = 0x%2.2x\n", header.e_ident[EI_VERSION]);
2953     s->Printf ("e_ident[EI_PAD    ] = 0x%2.2x\n", header.e_ident[EI_PAD]);
2954 
2955     s->Printf("e_type      = 0x%4.4x ", header.e_type);
2956     DumpELFHeader_e_type(s, header.e_type);
2957     s->Printf("\ne_machine   = 0x%4.4x\n", header.e_machine);
2958     s->Printf("e_version   = 0x%8.8x\n", header.e_version);
2959     s->Printf("e_entry     = 0x%8.8" PRIx64 "\n", header.e_entry);
2960     s->Printf("e_phoff     = 0x%8.8" PRIx64 "\n", header.e_phoff);
2961     s->Printf("e_shoff     = 0x%8.8" PRIx64 "\n", header.e_shoff);
2962     s->Printf("e_flags     = 0x%8.8x\n", header.e_flags);
2963     s->Printf("e_ehsize    = 0x%4.4x\n", header.e_ehsize);
2964     s->Printf("e_phentsize = 0x%4.4x\n", header.e_phentsize);
2965     s->Printf("e_phnum     = 0x%4.4x\n", header.e_phnum);
2966     s->Printf("e_shentsize = 0x%4.4x\n", header.e_shentsize);
2967     s->Printf("e_shnum     = 0x%4.4x\n", header.e_shnum);
2968     s->Printf("e_shstrndx  = 0x%4.4x\n", header.e_shstrndx);
2969 }
2970 
2971 //----------------------------------------------------------------------
2972 // DumpELFHeader_e_type
2973 //
2974 // Dump an token value for the ELF header member e_type
2975 //----------------------------------------------------------------------
2976 void
2977 ObjectFileELF::DumpELFHeader_e_type(Stream *s, elf_half e_type)
2978 {
2979     switch (e_type)
2980     {
2981     case ET_NONE:   *s << "ET_NONE"; break;
2982     case ET_REL:    *s << "ET_REL"; break;
2983     case ET_EXEC:   *s << "ET_EXEC"; break;
2984     case ET_DYN:    *s << "ET_DYN"; break;
2985     case ET_CORE:   *s << "ET_CORE"; break;
2986     default:
2987         break;
2988     }
2989 }
2990 
2991 //----------------------------------------------------------------------
2992 // DumpELFHeader_e_ident_EI_DATA
2993 //
2994 // Dump an token value for the ELF header member e_ident[EI_DATA]
2995 //----------------------------------------------------------------------
2996 void
2997 ObjectFileELF::DumpELFHeader_e_ident_EI_DATA(Stream *s, unsigned char ei_data)
2998 {
2999     switch (ei_data)
3000     {
3001     case ELFDATANONE:   *s << "ELFDATANONE"; break;
3002     case ELFDATA2LSB:   *s << "ELFDATA2LSB - Little Endian"; break;
3003     case ELFDATA2MSB:   *s << "ELFDATA2MSB - Big Endian"; break;
3004     default:
3005         break;
3006     }
3007 }
3008 
3009 
3010 //----------------------------------------------------------------------
3011 // DumpELFProgramHeader
3012 //
3013 // Dump a single ELF program header to the specified output stream
3014 //----------------------------------------------------------------------
3015 void
3016 ObjectFileELF::DumpELFProgramHeader(Stream *s, const ELFProgramHeader &ph)
3017 {
3018     DumpELFProgramHeader_p_type(s, ph.p_type);
3019     s->Printf(" %8.8" PRIx64 " %8.8" PRIx64 " %8.8" PRIx64, ph.p_offset, ph.p_vaddr, ph.p_paddr);
3020     s->Printf(" %8.8" PRIx64 " %8.8" PRIx64 " %8.8x (", ph.p_filesz, ph.p_memsz, ph.p_flags);
3021 
3022     DumpELFProgramHeader_p_flags(s, ph.p_flags);
3023     s->Printf(") %8.8" PRIx64, ph.p_align);
3024 }
3025 
3026 //----------------------------------------------------------------------
3027 // DumpELFProgramHeader_p_type
3028 //
3029 // Dump an token value for the ELF program header member p_type which
3030 // describes the type of the program header
3031 // ----------------------------------------------------------------------
3032 void
3033 ObjectFileELF::DumpELFProgramHeader_p_type(Stream *s, elf_word p_type)
3034 {
3035     const int kStrWidth = 15;
3036     switch (p_type)
3037     {
3038     CASE_AND_STREAM(s, PT_NULL        , kStrWidth);
3039     CASE_AND_STREAM(s, PT_LOAD        , kStrWidth);
3040     CASE_AND_STREAM(s, PT_DYNAMIC     , kStrWidth);
3041     CASE_AND_STREAM(s, PT_INTERP      , kStrWidth);
3042     CASE_AND_STREAM(s, PT_NOTE        , kStrWidth);
3043     CASE_AND_STREAM(s, PT_SHLIB       , kStrWidth);
3044     CASE_AND_STREAM(s, PT_PHDR        , kStrWidth);
3045     CASE_AND_STREAM(s, PT_TLS         , kStrWidth);
3046     CASE_AND_STREAM(s, PT_GNU_EH_FRAME, kStrWidth);
3047     default:
3048         s->Printf("0x%8.8x%*s", p_type, kStrWidth - 10, "");
3049         break;
3050     }
3051 }
3052 
3053 
3054 //----------------------------------------------------------------------
3055 // DumpELFProgramHeader_p_flags
3056 //
3057 // Dump an token value for the ELF program header member p_flags
3058 //----------------------------------------------------------------------
3059 void
3060 ObjectFileELF::DumpELFProgramHeader_p_flags(Stream *s, elf_word p_flags)
3061 {
3062     *s  << ((p_flags & PF_X) ? "PF_X" : "    ")
3063         << (((p_flags & PF_X) && (p_flags & PF_W)) ? '+' : ' ')
3064         << ((p_flags & PF_W) ? "PF_W" : "    ")
3065         << (((p_flags & PF_W) && (p_flags & PF_R)) ? '+' : ' ')
3066         << ((p_flags & PF_R) ? "PF_R" : "    ");
3067 }
3068 
3069 //----------------------------------------------------------------------
3070 // DumpELFProgramHeaders
3071 //
3072 // Dump all of the ELF program header to the specified output stream
3073 //----------------------------------------------------------------------
3074 void
3075 ObjectFileELF::DumpELFProgramHeaders(Stream *s)
3076 {
3077     if (!ParseProgramHeaders())
3078         return;
3079 
3080     s->PutCString("Program Headers\n");
3081     s->PutCString("IDX  p_type          p_offset p_vaddr  p_paddr  "
3082                   "p_filesz p_memsz  p_flags                   p_align\n");
3083     s->PutCString("==== --------------- -------- -------- -------- "
3084                   "-------- -------- ------------------------- --------\n");
3085 
3086     uint32_t idx = 0;
3087     for (ProgramHeaderCollConstIter I = m_program_headers.begin();
3088          I != m_program_headers.end(); ++I, ++idx)
3089     {
3090         s->Printf("[%2u] ", idx);
3091         ObjectFileELF::DumpELFProgramHeader(s, *I);
3092         s->EOL();
3093     }
3094 }
3095 
3096 //----------------------------------------------------------------------
3097 // DumpELFSectionHeader
3098 //
3099 // Dump a single ELF section header to the specified output stream
3100 //----------------------------------------------------------------------
3101 void
3102 ObjectFileELF::DumpELFSectionHeader(Stream *s, const ELFSectionHeaderInfo &sh)
3103 {
3104     s->Printf("%8.8x ", sh.sh_name);
3105     DumpELFSectionHeader_sh_type(s, sh.sh_type);
3106     s->Printf(" %8.8" PRIx64 " (", sh.sh_flags);
3107     DumpELFSectionHeader_sh_flags(s, sh.sh_flags);
3108     s->Printf(") %8.8" PRIx64 " %8.8" PRIx64 " %8.8" PRIx64, sh.sh_addr, sh.sh_offset, sh.sh_size);
3109     s->Printf(" %8.8x %8.8x", sh.sh_link, sh.sh_info);
3110     s->Printf(" %8.8" PRIx64 " %8.8" PRIx64, sh.sh_addralign, sh.sh_entsize);
3111 }
3112 
3113 //----------------------------------------------------------------------
3114 // DumpELFSectionHeader_sh_type
3115 //
3116 // Dump an token value for the ELF section header member sh_type which
3117 // describes the type of the section
3118 //----------------------------------------------------------------------
3119 void
3120 ObjectFileELF::DumpELFSectionHeader_sh_type(Stream *s, elf_word sh_type)
3121 {
3122     const int kStrWidth = 12;
3123     switch (sh_type)
3124     {
3125     CASE_AND_STREAM(s, SHT_NULL     , kStrWidth);
3126     CASE_AND_STREAM(s, SHT_PROGBITS , kStrWidth);
3127     CASE_AND_STREAM(s, SHT_SYMTAB   , kStrWidth);
3128     CASE_AND_STREAM(s, SHT_STRTAB   , kStrWidth);
3129     CASE_AND_STREAM(s, SHT_RELA     , kStrWidth);
3130     CASE_AND_STREAM(s, SHT_HASH     , kStrWidth);
3131     CASE_AND_STREAM(s, SHT_DYNAMIC  , kStrWidth);
3132     CASE_AND_STREAM(s, SHT_NOTE     , kStrWidth);
3133     CASE_AND_STREAM(s, SHT_NOBITS   , kStrWidth);
3134     CASE_AND_STREAM(s, SHT_REL      , kStrWidth);
3135     CASE_AND_STREAM(s, SHT_SHLIB    , kStrWidth);
3136     CASE_AND_STREAM(s, SHT_DYNSYM   , kStrWidth);
3137     CASE_AND_STREAM(s, SHT_LOPROC   , kStrWidth);
3138     CASE_AND_STREAM(s, SHT_HIPROC   , kStrWidth);
3139     CASE_AND_STREAM(s, SHT_LOUSER   , kStrWidth);
3140     CASE_AND_STREAM(s, SHT_HIUSER   , kStrWidth);
3141     default:
3142         s->Printf("0x%8.8x%*s", sh_type, kStrWidth - 10, "");
3143         break;
3144     }
3145 }
3146 
3147 //----------------------------------------------------------------------
3148 // DumpELFSectionHeader_sh_flags
3149 //
3150 // Dump an token value for the ELF section header member sh_flags
3151 //----------------------------------------------------------------------
3152 void
3153 ObjectFileELF::DumpELFSectionHeader_sh_flags(Stream *s, elf_xword sh_flags)
3154 {
3155     *s  << ((sh_flags & SHF_WRITE) ? "WRITE" : "     ")
3156         << (((sh_flags & SHF_WRITE) && (sh_flags & SHF_ALLOC)) ? '+' : ' ')
3157         << ((sh_flags & SHF_ALLOC) ? "ALLOC" : "     ")
3158         << (((sh_flags & SHF_ALLOC) && (sh_flags & SHF_EXECINSTR)) ? '+' : ' ')
3159         << ((sh_flags & SHF_EXECINSTR) ? "EXECINSTR" : "         ");
3160 }
3161 
3162 //----------------------------------------------------------------------
3163 // DumpELFSectionHeaders
3164 //
3165 // Dump all of the ELF section header to the specified output stream
3166 //----------------------------------------------------------------------
3167 void
3168 ObjectFileELF::DumpELFSectionHeaders(Stream *s)
3169 {
3170     if (!ParseSectionHeaders())
3171         return;
3172 
3173     s->PutCString("Section Headers\n");
3174     s->PutCString("IDX  name     type         flags                            "
3175                   "addr     offset   size     link     info     addralgn "
3176                   "entsize  Name\n");
3177     s->PutCString("==== -------- ------------ -------------------------------- "
3178                   "-------- -------- -------- -------- -------- -------- "
3179                   "-------- ====================\n");
3180 
3181     uint32_t idx = 0;
3182     for (SectionHeaderCollConstIter I = m_section_headers.begin();
3183          I != m_section_headers.end(); ++I, ++idx)
3184     {
3185         s->Printf("[%2u] ", idx);
3186         ObjectFileELF::DumpELFSectionHeader(s, *I);
3187         const char* section_name = I->section_name.AsCString("");
3188         if (section_name)
3189             *s << ' ' << section_name << "\n";
3190     }
3191 }
3192 
3193 void
3194 ObjectFileELF::DumpDependentModules(lldb_private::Stream *s)
3195 {
3196     size_t num_modules = ParseDependentModules();
3197 
3198     if (num_modules > 0)
3199     {
3200         s->PutCString("Dependent Modules:\n");
3201         for (unsigned i = 0; i < num_modules; ++i)
3202         {
3203             const FileSpec &spec = m_filespec_ap->GetFileSpecAtIndex(i);
3204             s->Printf("   %s\n", spec.GetFilename().GetCString());
3205         }
3206     }
3207 }
3208 
3209 bool
3210 ObjectFileELF::GetArchitecture (ArchSpec &arch)
3211 {
3212     if (!ParseHeader())
3213         return false;
3214 
3215     if (m_section_headers.empty())
3216     {
3217         // Allow elf notes to be parsed which may affect the detected architecture.
3218         ParseSectionHeaders();
3219     }
3220 
3221     if (CalculateType() == eTypeCoreFile && m_arch_spec.TripleOSIsUnspecifiedUnknown())
3222     {
3223         // Core files don't have section headers yet they have PT_NOTE program headers
3224         // that might shed more light on the architecture
3225         if (ParseProgramHeaders())
3226         {
3227             for (size_t i = 0, count = GetProgramHeaderCount(); i < count; ++i)
3228             {
3229                 const elf::ELFProgramHeader* header = GetProgramHeaderByIndex(i);
3230                 if (header && header->p_type == PT_NOTE && header->p_offset != 0 && header->p_filesz > 0)
3231                 {
3232                     DataExtractor data;
3233                     if (data.SetData (m_data, header->p_offset, header->p_filesz) == header->p_filesz)
3234                     {
3235                         lldb_private::UUID uuid;
3236                         RefineModuleDetailsFromNote (data, m_arch_spec, uuid);
3237                     }
3238                 }
3239             }
3240         }
3241     }
3242     arch = m_arch_spec;
3243     return true;
3244 }
3245 
3246 ObjectFile::Type
3247 ObjectFileELF::CalculateType()
3248 {
3249     switch (m_header.e_type)
3250     {
3251         case llvm::ELF::ET_NONE:
3252             // 0 - No file type
3253             return eTypeUnknown;
3254 
3255         case llvm::ELF::ET_REL:
3256             // 1 - Relocatable file
3257             return eTypeObjectFile;
3258 
3259         case llvm::ELF::ET_EXEC:
3260             // 2 - Executable file
3261             return eTypeExecutable;
3262 
3263         case llvm::ELF::ET_DYN:
3264             // 3 - Shared object file
3265             return eTypeSharedLibrary;
3266 
3267         case ET_CORE:
3268             // 4 - Core file
3269             return eTypeCoreFile;
3270 
3271         default:
3272             break;
3273     }
3274     return eTypeUnknown;
3275 }
3276 
3277 ObjectFile::Strata
3278 ObjectFileELF::CalculateStrata()
3279 {
3280     switch (m_header.e_type)
3281     {
3282         case llvm::ELF::ET_NONE:
3283             // 0 - No file type
3284             return eStrataUnknown;
3285 
3286         case llvm::ELF::ET_REL:
3287             // 1 - Relocatable file
3288             return eStrataUnknown;
3289 
3290         case llvm::ELF::ET_EXEC:
3291             // 2 - Executable file
3292             // TODO: is there any way to detect that an executable is a kernel
3293             // related executable by inspecting the program headers, section
3294             // headers, symbols, or any other flag bits???
3295             return eStrataUser;
3296 
3297         case llvm::ELF::ET_DYN:
3298             // 3 - Shared object file
3299             // TODO: is there any way to detect that an shared library is a kernel
3300             // related executable by inspecting the program headers, section
3301             // headers, symbols, or any other flag bits???
3302             return eStrataUnknown;
3303 
3304         case ET_CORE:
3305             // 4 - Core file
3306             // TODO: is there any way to detect that an core file is a kernel
3307             // related executable by inspecting the program headers, section
3308             // headers, symbols, or any other flag bits???
3309             return eStrataUnknown;
3310 
3311         default:
3312             break;
3313     }
3314     return eStrataUnknown;
3315 }
3316 
3317