llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp

   1 //===-- llvm-rtdyld.cpp - MCJIT Testing Tool ------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This is a testing tool for use with the MC-JIT LLVM components.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "llvm/ADT/StringMap.h"
  14 #include "llvm/DebugInfo/DIContext.h"
  15 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
  16 #include "llvm/ExecutionEngine/RTDyldMemoryManager.h"
  17 #include "llvm/ExecutionEngine/RuntimeDyld.h"
  18 #include "llvm/ExecutionEngine/RuntimeDyldChecker.h"
  19 #include "llvm/MC/MCAsmInfo.h"
  20 #include "llvm/MC/MCContext.h"
  21 #include "llvm/MC/MCDisassembler/MCDisassembler.h"
  22 #include "llvm/MC/MCInstPrinter.h"
  23 #include "llvm/MC/MCInstrInfo.h"
  24 #include "llvm/MC/MCRegisterInfo.h"
  25 #include "llvm/MC/MCSubtargetInfo.h"
  26 #include "llvm/MC/MCTargetOptions.h"
  27 #include "llvm/MC/TargetRegistry.h"
  28 #include "llvm/Object/SymbolSize.h"
  29 #include "llvm/Support/CommandLine.h"
  30 #include "llvm/Support/DynamicLibrary.h"
  31 #include "llvm/Support/FileSystem.h"
  32 #include "llvm/Support/InitLLVM.h"
  33 #include "llvm/Support/MSVCErrorWorkarounds.h"
  34 #include "llvm/Support/Memory.h"
  35 #include "llvm/Support/MemoryBuffer.h"
  36 #include "llvm/Support/Path.h"
  37 #include "llvm/Support/TargetSelect.h"
  38 #include "llvm/Support/Timer.h"
  39 #include "llvm/Support/raw_ostream.h"
  40
  41 #include <future>
  42 #include <list>
  43
  44 using namespace llvm;
  45 using namespace llvm::object;
  46
  47 static cl::OptionCategory RTDyldCategory("RTDyld Options");
  48
  49 static cl::list<std::string> InputFileList(cl::Positional,
  50                                            cl::desc("<input files>"),
  51                                            cl::cat(RTDyldCategory));
  52
  53 enum ActionType {
  54   AC_Execute,
  55   AC_PrintObjectLineInfo,
  56   AC_PrintLineInfo,
  57   AC_PrintDebugLineInfo,
  58   AC_Verify
  59 };
  60
  61 static cl::opt<ActionType> Action(
  62     cl::desc("Action to perform:"), cl::init(AC_Execute),
  63     cl::values(
  64         clEnumValN(AC_Execute, "execute",
  65                    "Load, link, and execute the inputs."),
  66         clEnumValN(AC_PrintLineInfo, "printline",
  67                    "Load, link, and print line information for each function."),
  68         clEnumValN(AC_PrintDebugLineInfo, "printdebugline",
  69                    "Load, link, and print line information for each function "
  70                    "using the debug object"),
  71         clEnumValN(AC_PrintObjectLineInfo, "printobjline",
  72                    "Like -printlineinfo but does not load the object first"),
  73         clEnumValN(AC_Verify, "verify",
  74                    "Load, link and verify the resulting memory image.")),
  75     cl::cat(RTDyldCategory));
  76
  77 static cl::opt<std::string>
  78     EntryPoint("entry", cl::desc("Function to call as entry point."),
  79                cl::init("_main"), cl::cat(RTDyldCategory));
  80
  81 static cl::list<std::string> Dylibs("dylib", cl::desc("Add library."),
  82                                     cl::cat(RTDyldCategory));
  83
  84 static cl::list<std::string> InputArgv("args", cl::Positional,
  85                                        cl::desc("<program arguments>..."),
  86                                        cl::PositionalEatsArgs,
  87                                        cl::cat(RTDyldCategory));
  88
  89 static cl::opt<std::string>
  90     TripleName("triple", cl::desc("Target triple for disassembler"),
  91                cl::cat(RTDyldCategory));
  92
  93 static cl::opt<std::string>
  94     MCPU("mcpu",
  95          cl::desc("Target a specific cpu type (-mcpu=help for details)"),
  96          cl::value_desc("cpu-name"), cl::init(""), cl::cat(RTDyldCategory));
  97
  98 static cl::list<std::string>
  99     CheckFiles("check",
 100                cl::desc("File containing RuntimeDyld verifier checks."),
 101                cl::cat(RTDyldCategory));
 102
 103 static cl::opt<uint64_t>
 104     PreallocMemory("preallocate",
 105                    cl::desc("Allocate memory upfront rather than on-demand"),
 106                    cl::init(0), cl::cat(RTDyldCategory));
 107
 108 static cl::opt<uint64_t> TargetAddrStart(
 109     "target-addr-start",
 110     cl::desc("For -verify only: start of phony target address "
 111              "range."),
 112     cl::init(4096), // Start at "page 1" - no allocating at "null".
 113     cl::Hidden, cl::cat(RTDyldCategory));
 114
 115 static cl::opt<uint64_t> TargetAddrEnd(
 116     "target-addr-end",
 117     cl::desc("For -verify only: end of phony target address range."),
 118     cl::init(~0ULL), cl::Hidden, cl::cat(RTDyldCategory));
 119
 120 static cl::opt<uint64_t> TargetSectionSep(
 121     "target-section-sep",
 122     cl::desc("For -verify only: Separation between sections in "
 123              "phony target address space."),
 124     cl::init(0), cl::Hidden, cl::cat(RTDyldCategory));
 125
 126 static cl::list<std::string>
 127     SpecificSectionMappings("map-section",
 128                             cl::desc("For -verify only: Map a section to a "
 129                                      "specific address."),
 130                             cl::Hidden, cl::cat(RTDyldCategory));
 131
 132 static cl::list<std::string> DummySymbolMappings(
 133     "dummy-extern",
 134     cl::desc("For -verify only: Inject a symbol into the extern "
 135              "symbol table."),
 136     cl::Hidden, cl::cat(RTDyldCategory));
 137
 138 static cl::opt<bool> PrintAllocationRequests(
 139     "print-alloc-requests",
 140     cl::desc("Print allocation requests made to the memory "
 141              "manager by RuntimeDyld"),
 142     cl::Hidden, cl::cat(RTDyldCategory));
 143
 144 static cl::opt<bool> ShowTimes("show-times",
 145                                cl::desc("Show times for llvm-rtdyld phases"),
 146                                cl::init(false), cl::cat(RTDyldCategory));
 147
 148 ExitOnError ExitOnErr;
 149
 150 struct RTDyldTimers {
 151   TimerGroup RTDyldTG{"llvm-rtdyld timers", "timers for llvm-rtdyld phases"};
 152   Timer LoadObjectsTimer{"load", "time to load/add object files", RTDyldTG};
 153   Timer LinkTimer{"link", "time to link object files", RTDyldTG};
 154   Timer RunTimer{"run", "time to execute jitlink'd code", RTDyldTG};
 155 };
 156
 157 std::unique_ptr<RTDyldTimers> Timers;
 158
 159 /* *** */
 160
 161 using SectionIDMap = StringMap<unsigned>;
 162 using FileToSectionIDMap = StringMap<SectionIDMap>;
 163
 164 void dumpFileToSectionIDMap(const FileToSectionIDMap &FileToSecIDMap) {
 165   for (const auto &KV : FileToSecIDMap) {
 166     llvm::dbgs() << "In " << KV.first() << "\n";
 167     for (auto &KV2 : KV.second)
 168       llvm::dbgs() << "  \"" << KV2.first() << "\" -> " << KV2.second << "\n";
 169   }
 170 }
 171
 172 Expected<unsigned> getSectionId(const FileToSectionIDMap &FileToSecIDMap,
 173                                 StringRef FileName, StringRef SectionName) {
 174   auto I = FileToSecIDMap.find(FileName);
 175   if (I == FileToSecIDMap.end())
 176     return make_error<StringError>("No file named " + FileName,
 177                                    inconvertibleErrorCode());
 178   auto &SectionIDs = I->second;
 179   auto J = SectionIDs.find(SectionName);
 180   if (J == SectionIDs.end())
 181     return make_error<StringError>("No section named \"" + SectionName +
 182                                    "\" in file " + FileName,
 183                                    inconvertibleErrorCode());
 184   return J->second;
 185 }
 186
 187 // A trivial memory manager that doesn't do anything fancy, just uses the
 188 // support library allocation routines directly.
 189 class TrivialMemoryManager : public RTDyldMemoryManager {
 190 public:
 191   struct SectionInfo {
 192     SectionInfo(StringRef Name, sys::MemoryBlock MB, unsigned SectionID)
 193         : Name(std::string(Name)), MB(std::move(MB)), SectionID(SectionID) {}
 194     std::string Name;
 195     sys::MemoryBlock MB;
 196     unsigned SectionID = ~0U;
 197   };
 198
 199   SmallVector<SectionInfo, 16> FunctionMemory;
 200   SmallVector<SectionInfo, 16> DataMemory;
 201
 202   uint8_t *allocateCodeSection(uintptr_t Size, unsigned Alignment,
 203                                unsigned SectionID,
 204                                StringRef SectionName) override;
 205   uint8_t *allocateDataSection(uintptr_t Size, unsigned Alignment,
 206                                unsigned SectionID, StringRef SectionName,
 207                                bool IsReadOnly) override;
 208   TrivialMemoryManager::TLSSection
 209   allocateTLSSection(uintptr_t Size, unsigned Alignment, unsigned SectionID,
 210                      StringRef SectionName) override;
 211
 212   /// If non null, records subsequent Name -> SectionID mappings.
 213   void setSectionIDsMap(SectionIDMap *SecIDMap) {
 214     this->SecIDMap = SecIDMap;
 215   }
 216
 217   void *getPointerToNamedFunction(const std::string &Name,
 218                                   bool AbortOnFailure = true) override {
 219     return nullptr;
 220   }
 221
 222   bool finalizeMemory(std::string *ErrMsg) override { return false; }
 223
 224   void addDummySymbol(const std::string &Name, uint64_t Addr) {
 225     DummyExterns[Name] = Addr;
 226   }
 227
 228   JITSymbol findSymbol(const std::string &Name) override {
 229     auto I = DummyExterns.find(Name);
 230
 231     if (I != DummyExterns.end())
 232       return JITSymbol(I->second, JITSymbolFlags::Exported);
 233
 234     if (auto Sym = RTDyldMemoryManager::findSymbol(Name))
 235       return Sym;
 236     else if (auto Err = Sym.takeError())
 237       ExitOnErr(std::move(Err));
 238     else
 239       ExitOnErr(make_error<StringError>("Could not find definition for \"" +
 240                                             Name + "\"",
 241                                         inconvertibleErrorCode()));
 242     llvm_unreachable("Should have returned or exited by now");
 243   }
 244
 245   void registerEHFrames(uint8_t *Addr, uint64_t LoadAddr,
 246                         size_t Size) override {}
 247   void deregisterEHFrames() override {}
 248
 249   void preallocateSlab(uint64_t Size) {
 250     std::error_code EC;
 251     sys::MemoryBlock MB =
 252       sys::Memory::allocateMappedMemory(Size, nullptr,
 253                                         sys::Memory::MF_READ |
 254                                         sys::Memory::MF_WRITE,
 255                                         EC);
 256     if (!MB.base())
 257       report_fatal_error(Twine("Can't allocate enough memory: ") +
 258                          EC.message());
 259
 260     PreallocSlab = MB;
 261     UsePreallocation = true;
 262     SlabSize = Size;
 263   }
 264
 265   uint8_t *allocateFromSlab(uintptr_t Size, unsigned Alignment, bool isCode,
 266                             StringRef SectionName, unsigned SectionID) {
 267     Size = alignTo(Size, Alignment);
 268     if (CurrentSlabOffset + Size > SlabSize)
 269       report_fatal_error("Can't allocate enough memory. Tune --preallocate");
 270
 271     uintptr_t OldSlabOffset = CurrentSlabOffset;
 272     sys::MemoryBlock MB((void *)OldSlabOffset, Size);
 273     if (isCode)
 274       FunctionMemory.push_back(SectionInfo(SectionName, MB, SectionID));
 275     else
 276       DataMemory.push_back(SectionInfo(SectionName, MB, SectionID));
 277     CurrentSlabOffset += Size;
 278     return (uint8_t*)OldSlabOffset;
 279   }
 280
 281 private:
 282   std::map<std::string, uint64_t> DummyExterns;
 283   sys::MemoryBlock PreallocSlab;
 284   bool UsePreallocation = false;
 285   uintptr_t SlabSize = 0;
 286   uintptr_t CurrentSlabOffset = 0;
 287   SectionIDMap *SecIDMap = nullptr;
 288 #if defined(__x86_64__) && defined(__ELF__) && defined(__linux__)
 289   unsigned UsedTLSStorage = 0;
 290 #endif
 291 };
 292
 293 uint8_t *TrivialMemoryManager::allocateCodeSection(uintptr_t Size,
 294                                                    unsigned Alignment,
 295                                                    unsigned SectionID,
 296                                                    StringRef SectionName) {
 297   if (PrintAllocationRequests)
 298     outs() << "allocateCodeSection(Size = " << Size << ", Alignment = "
 299            << Alignment << ", SectionName = " << SectionName << ")\n";
 300
 301   if (SecIDMap)
 302     (*SecIDMap)[SectionName] = SectionID;
 303
 304   if (UsePreallocation)
 305     return allocateFromSlab(Size, Alignment, true /* isCode */,
 306                             SectionName, SectionID);
 307
 308   std::error_code EC;
 309   sys::MemoryBlock MB =
 310     sys::Memory::allocateMappedMemory(Size, nullptr,
 311                                       sys::Memory::MF_READ |
 312                                       sys::Memory::MF_WRITE,
 313                                       EC);
 314   if (!MB.base())
 315     report_fatal_error(Twine("MemoryManager allocation failed: ") +
 316                        EC.message());
 317   FunctionMemory.push_back(SectionInfo(SectionName, MB, SectionID));
 318   return (uint8_t*)MB.base();
 319 }
 320
 321 uint8_t *TrivialMemoryManager::allocateDataSection(uintptr_t Size,
 322                                                    unsigned Alignment,
 323                                                    unsigned SectionID,
 324                                                    StringRef SectionName,
 325                                                    bool IsReadOnly) {
 326   if (PrintAllocationRequests)
 327     outs() << "allocateDataSection(Size = " << Size << ", Alignment = "
 328            << Alignment << ", SectionName = " << SectionName << ")\n";
 329
 330   if (SecIDMap)
 331     (*SecIDMap)[SectionName] = SectionID;
 332
 333   if (UsePreallocation)
 334     return allocateFromSlab(Size, Alignment, false /* isCode */, SectionName,
 335                             SectionID);
 336
 337   std::error_code EC;
 338   sys::MemoryBlock MB =
 339     sys::Memory::allocateMappedMemory(Size, nullptr,
 340                                       sys::Memory::MF_READ |
 341                                       sys::Memory::MF_WRITE,
 342                                       EC);
 343   if (!MB.base())
 344     report_fatal_error(Twine("MemoryManager allocation failed: ") +
 345                        EC.message());
 346   DataMemory.push_back(SectionInfo(SectionName, MB, SectionID));
 347   return (uint8_t*)MB.base();
 348 }
 349
 350 // In case the execution needs TLS storage, we define a very small TLS memory
 351 // area here that will be used in allocateTLSSection().
 352 #if defined(__x86_64__) && defined(__ELF__) && defined(__linux__)
 353 extern "C" {
 354 alignas(16) __attribute__((visibility("hidden"), tls_model("initial-exec"),
 355                            used)) thread_local char LLVMRTDyldTLSSpace[16];
 356 }
 357 #endif
 358
 359 TrivialMemoryManager::TLSSection
 360 TrivialMemoryManager::allocateTLSSection(uintptr_t Size, unsigned Alignment,
 361                                          unsigned SectionID,
 362                                          StringRef SectionName) {
 363 #if defined(__x86_64__) && defined(__ELF__) && defined(__linux__)
 364   if (Size + UsedTLSStorage > sizeof(LLVMRTDyldTLSSpace)) {
 365     return {};
 366   }
 367
 368   // Get the offset of the TLSSpace in the TLS block by using a tpoff
 369   // relocation here.
 370   int64_t TLSOffset;
 371   asm("leaq LLVMRTDyldTLSSpace@tpoff, %0" : "=r"(TLSOffset));
 372
 373   TLSSection Section;
 374   // We use the storage directly as the initialization image. This means that
 375   // when a new thread is spawned after this allocation, it will not be
 376   // initialized correctly. This means, llvm-rtdyld will only support TLS in a
 377   // single thread.
 378   Section.InitializationImage =
 379       reinterpret_cast<uint8_t *>(LLVMRTDyldTLSSpace + UsedTLSStorage);
 380   Section.Offset = TLSOffset + UsedTLSStorage;
 381
 382   UsedTLSStorage += Size;
 383
 384   return Section;
 385 #else
 386   return {};
 387 #endif
 388 }
 389
 390 static const char *ProgramName;
 391
 392 static void ErrorAndExit(const Twine &Msg) {
 393   errs() << ProgramName << ": error: " << Msg << "\n";
 394   exit(1);
 395 }
 396
 397 static void loadDylibs() {
 398   for (const std::string &Dylib : Dylibs) {
 399     if (!sys::fs::is_regular_file(Dylib))
 400       report_fatal_error(Twine("Dylib not found: '") + Dylib + "'.");
 401     std::string ErrMsg;
 402     if (sys::DynamicLibrary::LoadLibraryPermanently(Dylib.c_str(), &ErrMsg))
 403       report_fatal_error(Twine("Error loading '") + Dylib + "': " + ErrMsg);
 404   }
 405 }
 406
 407 /* *** */
 408
 409 static int printLineInfoForInput(bool LoadObjects, bool UseDebugObj) {
 410   assert(LoadObjects || !UseDebugObj);
 411
 412   // Load any dylibs requested on the command line.
 413   loadDylibs();
 414
 415   // If we don't have any input files, read from stdin.
 416   if (!InputFileList.size())
 417     InputFileList.push_back("-");
 418   for (auto &File : InputFileList) {
 419     // Instantiate a dynamic linker.
 420     TrivialMemoryManager MemMgr;
 421     RuntimeDyld Dyld(MemMgr, MemMgr);
 422
 423     // Load the input memory buffer.
 424
 425     ErrorOr<std::unique_ptr<MemoryBuffer>> InputBuffer =
 426         MemoryBuffer::getFileOrSTDIN(File);
 427     if (std::error_code EC = InputBuffer.getError())
 428       ErrorAndExit("unable to read input: '" + EC.message() + "'");
 429
 430     Expected<std::unique_ptr<ObjectFile>> MaybeObj(
 431       ObjectFile::createObjectFile((*InputBuffer)->getMemBufferRef()));
 432
 433     if (!MaybeObj) {
 434       std::string Buf;
 435       raw_string_ostream OS(Buf);
 436       logAllUnhandledErrors(MaybeObj.takeError(), OS);
 437       OS.flush();
 438       ErrorAndExit("unable to create object file: '" + Buf + "'");
 439     }
 440
 441     ObjectFile &Obj = **MaybeObj;
 442
 443     OwningBinary<ObjectFile> DebugObj;
 444     std::unique_ptr<RuntimeDyld::LoadedObjectInfo> LoadedObjInfo = nullptr;
 445     ObjectFile *SymbolObj = &Obj;
 446     if (LoadObjects) {
 447       // Load the object file
 448       LoadedObjInfo =
 449         Dyld.loadObject(Obj);
 450
 451       if (Dyld.hasError())
 452         ErrorAndExit(Dyld.getErrorString());
 453
 454       // Resolve all the relocations we can.
 455       Dyld.resolveRelocations();
 456
 457       if (UseDebugObj) {
 458         DebugObj = LoadedObjInfo->getObjectForDebug(Obj);
 459         SymbolObj = DebugObj.getBinary();
 460         LoadedObjInfo.reset();
 461       }
 462     }
 463
 464     std::unique_ptr<DIContext> Context = DWARFContext::create(
 465         *SymbolObj, DWARFContext::ProcessDebugRelocations::Process,
 466         LoadedObjInfo.get());
 467
 468     std::vector<std::pair<SymbolRef, uint64_t>> SymAddr =
 469         object::computeSymbolSizes(*SymbolObj);
 470
 471     // Use symbol info to iterate functions in the object.
 472     for (const auto &P : SymAddr) {
 473       object::SymbolRef Sym = P.first;
 474       Expected<SymbolRef::Type> TypeOrErr = Sym.getType();
 475       if (!TypeOrErr) {
 476         // TODO: Actually report errors helpfully.
 477         consumeError(TypeOrErr.takeError());
 478         continue;
 479       }
 480       SymbolRef::Type Type = *TypeOrErr;
 481       if (Type == object::SymbolRef::ST_Function) {
 482         Expected<StringRef> Name = Sym.getName();
 483         if (!Name) {
 484           // TODO: Actually report errors helpfully.
 485           consumeError(Name.takeError());
 486           continue;
 487         }
 488         Expected<uint64_t> AddrOrErr = Sym.getAddress();
 489         if (!AddrOrErr) {
 490           // TODO: Actually report errors helpfully.
 491           consumeError(AddrOrErr.takeError());
 492           continue;
 493         }
 494         uint64_t Addr = *AddrOrErr;
 495
 496         object::SectionedAddress Address;
 497
 498         uint64_t Size = P.second;
 499         // If we're not using the debug object, compute the address of the
 500         // symbol in memory (rather than that in the unrelocated object file)
 501         // and use that to query the DWARFContext.
 502         if (!UseDebugObj && LoadObjects) {
 503           auto SecOrErr = Sym.getSection();
 504           if (!SecOrErr) {
 505             // TODO: Actually report errors helpfully.
 506             consumeError(SecOrErr.takeError());
 507             continue;
 508           }
 509           object::section_iterator Sec = *SecOrErr;
 510           Address.SectionIndex = Sec->getIndex();
 511           uint64_t SectionLoadAddress =
 512             LoadedObjInfo->getSectionLoadAddress(*Sec);
 513           if (SectionLoadAddress != 0)
 514             Addr += SectionLoadAddress - Sec->getAddress();
 515         } else if (auto SecOrErr = Sym.getSection())
 516           Address.SectionIndex = SecOrErr.get()->getIndex();
 517
 518         outs() << "Function: " << *Name << ", Size = " << Size
 519                << ", Addr = " << Addr << "\n";
 520
 521         Address.Address = Addr;
 522         DILineInfoTable Lines =
 523             Context->getLineInfoForAddressRange(Address, Size);
 524         for (auto &D : Lines) {
 525           outs() << "  Line info @ " << D.first - Addr << ": "
 526                  << D.second.FileName << ", line:" << D.second.Line << "\n";
 527         }
 528       }
 529     }
 530   }
 531
 532   return 0;
 533 }
 534
 535 static void doPreallocation(TrivialMemoryManager &MemMgr) {
 536   // Allocate a slab of memory upfront, if required. This is used if
 537   // we want to test small code models.
 538   if (static_cast<intptr_t>(PreallocMemory) < 0)
 539     report_fatal_error("Pre-allocated bytes of memory must be a positive integer.");
 540
 541   // FIXME: Limit the amount of memory that can be preallocated?
 542   if (PreallocMemory != 0)
 543     MemMgr.preallocateSlab(PreallocMemory);
 544 }
 545
 546 static int executeInput() {
 547   // Load any dylibs requested on the command line.
 548   loadDylibs();
 549
 550   // Instantiate a dynamic linker.
 551   TrivialMemoryManager MemMgr;
 552   doPreallocation(MemMgr);
 553   RuntimeDyld Dyld(MemMgr, MemMgr);
 554
 555   // If we don't have any input files, read from stdin.
 556   if (!InputFileList.size())
 557     InputFileList.push_back("-");
 558   {
 559     TimeRegion TR(Timers ? &Timers->LoadObjectsTimer : nullptr);
 560     for (auto &File : InputFileList) {
 561       // Load the input memory buffer.
 562       ErrorOr<std::unique_ptr<MemoryBuffer>> InputBuffer =
 563           MemoryBuffer::getFileOrSTDIN(File);
 564       if (std::error_code EC = InputBuffer.getError())
 565         ErrorAndExit("unable to read input: '" + EC.message() + "'");
 566       Expected<std::unique_ptr<ObjectFile>> MaybeObj(
 567           ObjectFile::createObjectFile((*InputBuffer)->getMemBufferRef()));
 568
 569       if (!MaybeObj) {
 570         std::string Buf;
 571         raw_string_ostream OS(Buf);
 572         logAllUnhandledErrors(MaybeObj.takeError(), OS);
 573         OS.flush();
 574         ErrorAndExit("unable to create object file: '" + Buf + "'");
 575       }
 576
 577       ObjectFile &Obj = **MaybeObj;
 578
 579       // Load the object file
 580       Dyld.loadObject(Obj);
 581       if (Dyld.hasError()) {
 582         ErrorAndExit(Dyld.getErrorString());
 583       }
 584     }
 585   }
 586
 587   {
 588     TimeRegion TR(Timers ? &Timers->LinkTimer : nullptr);
 589     // Resove all the relocations we can.
 590     // FIXME: Error out if there are unresolved relocations.
 591     Dyld.resolveRelocations();
 592   }
 593
 594   // Get the address of the entry point (_main by default).
 595   void *MainAddress = Dyld.getSymbolLocalAddress(EntryPoint);
 596   if (!MainAddress)
 597     ErrorAndExit("no definition for '" + EntryPoint + "'");
 598
 599   // Invalidate the instruction cache for each loaded function.
 600   for (auto &FM : MemMgr.FunctionMemory) {
 601
 602     auto &FM_MB = FM.MB;
 603
 604     // Make sure the memory is executable.
 605     // setExecutable will call InvalidateInstructionCache.
 606     if (auto EC = sys::Memory::protectMappedMemory(FM_MB,
 607                                                    sys::Memory::MF_READ |
 608                                                    sys::Memory::MF_EXEC))
 609       ErrorAndExit("unable to mark function executable: '" + EC.message() +
 610                    "'");
 611   }
 612
 613   // Dispatch to _main().
 614   errs() << "loaded '" << EntryPoint << "' at: " << (void*)MainAddress << "\n";
 615
 616   int (*Main)(int, const char**) =
 617     (int(*)(int,const char**)) uintptr_t(MainAddress);
 618   std::vector<const char *> Argv;
 619   // Use the name of the first input object module as argv[0] for the target.
 620   Argv.push_back(InputFileList[0].data());
 621   for (auto &Arg : InputArgv)
 622     Argv.push_back(Arg.data());
 623   Argv.push_back(nullptr);
 624   int Result = 0;
 625   {
 626     TimeRegion TR(Timers ? &Timers->RunTimer : nullptr);
 627     Result = Main(Argv.size() - 1, Argv.data());
 628   }
 629
 630   return Result;
 631 }
 632
 633 static int checkAllExpressions(RuntimeDyldChecker &Checker) {
 634   for (const auto& CheckerFileName : CheckFiles) {
 635     ErrorOr<std::unique_ptr<MemoryBuffer>> CheckerFileBuf =
 636         MemoryBuffer::getFileOrSTDIN(CheckerFileName);
 637     if (std::error_code EC = CheckerFileBuf.getError())
 638       ErrorAndExit("unable to read input '" + CheckerFileName + "': " +
 639                    EC.message());
 640
 641     if (!Checker.checkAllRulesInBuffer("# rtdyld-check:",
 642                                        CheckerFileBuf.get().get()))
 643       ErrorAndExit("some checks in '" + CheckerFileName + "' failed");
 644   }
 645   return 0;
 646 }
 647
 648 void applySpecificSectionMappings(RuntimeDyld &Dyld,
 649                                   const FileToSectionIDMap &FileToSecIDMap) {
 650
 651   for (StringRef Mapping : SpecificSectionMappings) {
 652     size_t EqualsIdx = Mapping.find_first_of("=");
 653     std::string SectionIDStr = std::string(Mapping.substr(0, EqualsIdx));
 654     size_t ComaIdx = Mapping.find_first_of(",");
 655
 656     if (ComaIdx == StringRef::npos)
 657       report_fatal_error("Invalid section specification '" + Mapping +
 658                          "'. Should be '<file name>,<section name>=<addr>'");
 659
 660     std::string FileName = SectionIDStr.substr(0, ComaIdx);
 661     std::string SectionName = SectionIDStr.substr(ComaIdx + 1);
 662     unsigned SectionID =
 663       ExitOnErr(getSectionId(FileToSecIDMap, FileName, SectionName));
 664
 665     auto* OldAddr = Dyld.getSectionContent(SectionID).data();
 666     std::string NewAddrStr = std::string(Mapping.substr(EqualsIdx + 1));
 667     uint64_t NewAddr;
 668
 669     if (StringRef(NewAddrStr).getAsInteger(0, NewAddr))
 670       report_fatal_error("Invalid section address in mapping '" + Mapping +
 671                          "'.");
 672
 673     Dyld.mapSectionAddress(OldAddr, NewAddr);
 674   }
 675 }
 676
 677 // Scatter sections in all directions!
 678 // Remaps section addresses for -verify mode. The following command line options
 679 // can be used to customize the layout of the memory within the phony target's
 680 // address space:
 681 // -target-addr-start <s> -- Specify where the phony target address range starts.
 682 // -target-addr-end   <e> -- Specify where the phony target address range ends.
 683 // -target-section-sep <d> -- Specify how big a gap should be left between the
 684 //                            end of one section and the start of the next.
 685 //                            Defaults to zero. Set to something big
 686 //                            (e.g. 1 << 32) to stress-test stubs, GOTs, etc.
 687 //
 688 static void remapSectionsAndSymbols(const llvm::Triple &TargetTriple,
 689                                     RuntimeDyld &Dyld,
 690                                     TrivialMemoryManager &MemMgr) {
 691
 692   // Set up a work list (section addr/size pairs).
 693   typedef std::list<const TrivialMemoryManager::SectionInfo*> WorklistT;
 694   WorklistT Worklist;
 695
 696   for (const auto& CodeSection : MemMgr.FunctionMemory)
 697     Worklist.push_back(&CodeSection);
 698   for (const auto& DataSection : MemMgr.DataMemory)
 699     Worklist.push_back(&DataSection);
 700
 701   // Keep an "already allocated" mapping of section target addresses to sizes.
 702   // Sections whose address mappings aren't specified on the command line will
 703   // allocated around the explicitly mapped sections while maintaining the
 704   // minimum separation.
 705   std::map<uint64_t, uint64_t> AlreadyAllocated;
 706
 707   // Move the previously applied mappings (whether explicitly specified on the
 708   // command line, or implicitly set by RuntimeDyld) into the already-allocated
 709   // map.
 710   for (WorklistT::iterator I = Worklist.begin(), E = Worklist.end();
 711        I != E;) {
 712     WorklistT::iterator Tmp = I;
 713     ++I;
 714
 715     auto LoadAddr = Dyld.getSectionLoadAddress((*Tmp)->SectionID);
 716
 717     if (LoadAddr != static_cast<uint64_t>(
 718           reinterpret_cast<uintptr_t>((*Tmp)->MB.base()))) {
 719       // A section will have a LoadAddr of 0 if it wasn't loaded for whatever
 720       // reason (e.g. zero byte COFF sections). Don't include those sections in
 721       // the allocation map.
 722       if (LoadAddr != 0)
 723         AlreadyAllocated[LoadAddr] = (*Tmp)->MB.allocatedSize();
 724       Worklist.erase(Tmp);
 725     }
 726   }
 727
 728   // If the -target-addr-end option wasn't explicitly passed, then set it to a
 729   // sensible default based on the target triple.
 730   if (TargetAddrEnd.getNumOccurrences() == 0) {
 731     if (TargetTriple.isArch16Bit())
 732       TargetAddrEnd = (1ULL << 16) - 1;
 733     else if (TargetTriple.isArch32Bit())
 734       TargetAddrEnd = (1ULL << 32) - 1;
 735     // TargetAddrEnd already has a sensible default for 64-bit systems, so
 736     // there's nothing to do in the 64-bit case.
 737   }
 738
 739   // Process any elements remaining in the worklist.
 740   while (!Worklist.empty()) {
 741     auto *CurEntry = Worklist.front();
 742     Worklist.pop_front();
 743
 744     uint64_t NextSectionAddr = TargetAddrStart;
 745
 746     for (const auto &Alloc : AlreadyAllocated)
 747       if (NextSectionAddr + CurEntry->MB.allocatedSize() + TargetSectionSep <=
 748           Alloc.first)
 749         break;
 750       else
 751         NextSectionAddr = Alloc.first + Alloc.second + TargetSectionSep;
 752
 753     Dyld.mapSectionAddress(CurEntry->MB.base(), NextSectionAddr);
 754     AlreadyAllocated[NextSectionAddr] = CurEntry->MB.allocatedSize();
 755   }
 756
 757   // Add dummy symbols to the memory manager.
 758   for (const auto &Mapping : DummySymbolMappings) {
 759     size_t EqualsIdx = Mapping.find_first_of('=');
 760
 761     if (EqualsIdx == StringRef::npos)
 762       report_fatal_error(Twine("Invalid dummy symbol specification '") +
 763                          Mapping + "'. Should be '<symbol name>=<addr>'");
 764
 765     std::string Symbol = Mapping.substr(0, EqualsIdx);
 766     std::string AddrStr = Mapping.substr(EqualsIdx + 1);
 767
 768     uint64_t Addr;
 769     if (StringRef(AddrStr).getAsInteger(0, Addr))
 770       report_fatal_error(Twine("Invalid symbol mapping '") + Mapping + "'.");
 771
 772     MemMgr.addDummySymbol(Symbol, Addr);
 773   }
 774 }
 775
 776 // Load and link the objects specified on the command line, but do not execute
 777 // anything. Instead, attach a RuntimeDyldChecker instance and call it to
 778 // verify the correctness of the linked memory.
 779 static int linkAndVerify() {
 780
 781   // Check for missing triple.
 782   if (TripleName == "")
 783     ErrorAndExit("-triple required when running in -verify mode.");
 784
 785   // Look up the target and build the disassembler.
 786   Triple TheTriple(Triple::normalize(TripleName));
 787   std::string ErrorStr;
 788   const Target *TheTarget =
 789     TargetRegistry::lookupTarget("", TheTriple, ErrorStr);
 790   if (!TheTarget)
 791     ErrorAndExit("Error accessing target '" + TripleName + "': " + ErrorStr);
 792
 793   TripleName = TheTriple.getTriple();
 794
 795   std::unique_ptr<MCSubtargetInfo> STI(
 796     TheTarget->createMCSubtargetInfo(TripleName, MCPU, ""));
 797   if (!STI)
 798     ErrorAndExit("Unable to create subtarget info!");
 799
 800   std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TripleName));
 801   if (!MRI)
 802     ErrorAndExit("Unable to create target register info!");
 803
 804   MCTargetOptions MCOptions;
 805   std::unique_ptr<MCAsmInfo> MAI(
 806       TheTarget->createMCAsmInfo(*MRI, TripleName, MCOptions));
 807   if (!MAI)
 808     ErrorAndExit("Unable to create target asm info!");
 809
 810   MCContext Ctx(Triple(TripleName), MAI.get(), MRI.get(), STI.get());
 811
 812   std::unique_ptr<MCDisassembler> Disassembler(
 813     TheTarget->createMCDisassembler(*STI, Ctx));
 814   if (!Disassembler)
 815     ErrorAndExit("Unable to create disassembler!");
 816
 817   std::unique_ptr<MCInstrInfo> MII(TheTarget->createMCInstrInfo());
 818   if (!MII)
 819     ErrorAndExit("Unable to create target instruction info!");
 820
 821   std::unique_ptr<MCInstPrinter> InstPrinter(
 822       TheTarget->createMCInstPrinter(Triple(TripleName), 0, *MAI, *MII, *MRI));
 823
 824   // Load any dylibs requested on the command line.
 825   loadDylibs();
 826
 827   // Instantiate a dynamic linker.
 828   TrivialMemoryManager MemMgr;
 829   doPreallocation(MemMgr);
 830
 831   struct StubID {
 832     unsigned SectionID;
 833     uint32_t Offset;
 834   };
 835   using StubInfos = StringMap<StubID>;
 836   using StubContainers = StringMap<StubInfos>;
 837
 838   StubContainers StubMap;
 839   RuntimeDyld Dyld(MemMgr, MemMgr);
 840   Dyld.setProcessAllSections(true);
 841
 842   Dyld.setNotifyStubEmitted([&StubMap](StringRef FilePath,
 843                                        StringRef SectionName,
 844                                        StringRef SymbolName, unsigned SectionID,
 845                                        uint32_t StubOffset) {
 846     std::string ContainerName =
 847         (sys::path::filename(FilePath) + "/" + SectionName).str();
 848     StubMap[ContainerName][SymbolName] = {SectionID, StubOffset};
 849   });
 850
 851   auto GetSymbolInfo =
 852       [&Dyld, &MemMgr](
 853           StringRef Symbol) -> Expected<RuntimeDyldChecker::MemoryRegionInfo> {
 854     RuntimeDyldChecker::MemoryRegionInfo SymInfo;
 855
 856     // First get the target address.
 857     if (auto InternalSymbol = Dyld.getSymbol(Symbol))
 858       SymInfo.setTargetAddress(InternalSymbol.getAddress());
 859     else {
 860       // Symbol not found in RuntimeDyld. Fall back to external lookup.
 861 #ifdef _MSC_VER
 862       using ExpectedLookupResult =
 863           MSVCPExpected<JITSymbolResolver::LookupResult>;
 864 #else
 865       using ExpectedLookupResult = Expected<JITSymbolResolver::LookupResult>;
 866 #endif
 867
 868       auto ResultP = std::make_shared<std::promise<ExpectedLookupResult>>();
 869       auto ResultF = ResultP->get_future();
 870
 871       MemMgr.lookup(JITSymbolResolver::LookupSet({Symbol}),
 872                     [=](Expected<JITSymbolResolver::LookupResult> Result) {
 873                       ResultP->set_value(std::move(Result));
 874                     });
 875
 876       auto Result = ResultF.get();
 877       if (!Result)
 878         return Result.takeError();
 879
 880       auto I = Result->find(Symbol);
 881       assert(I != Result->end() &&
 882              "Expected symbol address if no error occurred");
 883       SymInfo.setTargetAddress(I->second.getAddress());
 884     }
 885
 886     // Now find the symbol content if possible (otherwise leave content as a
 887     // default-constructed StringRef).
 888     if (auto *SymAddr = Dyld.getSymbolLocalAddress(Symbol)) {
 889       unsigned SectionID = Dyld.getSymbolSectionID(Symbol);
 890       if (SectionID != ~0U) {
 891         char *CSymAddr = static_cast<char *>(SymAddr);
 892         StringRef SecContent = Dyld.getSectionContent(SectionID);
 893         uint64_t SymSize = SecContent.size() - (CSymAddr - SecContent.data());
 894         SymInfo.setContent(ArrayRef<char>(CSymAddr, SymSize));
 895         SymInfo.setTargetFlags(
 896             Dyld.getSymbol(Symbol).getFlags().getTargetFlags());
 897       }
 898     }
 899     return SymInfo;
 900   };
 901
 902   auto IsSymbolValid = [&Dyld, GetSymbolInfo](StringRef Symbol) {
 903     if (Dyld.getSymbol(Symbol))
 904       return true;
 905     auto SymInfo = GetSymbolInfo(Symbol);
 906     if (!SymInfo) {
 907       logAllUnhandledErrors(SymInfo.takeError(), errs(), "RTDyldChecker: ");
 908       return false;
 909     }
 910     return SymInfo->getTargetAddress() != 0;
 911   };
 912
 913   FileToSectionIDMap FileToSecIDMap;
 914
 915   auto GetSectionInfo = [&Dyld, &FileToSecIDMap](StringRef FileName,
 916                                                  StringRef SectionName)
 917       -> Expected<RuntimeDyldChecker::MemoryRegionInfo> {
 918     auto SectionID = getSectionId(FileToSecIDMap, FileName, SectionName);
 919     if (!SectionID)
 920       return SectionID.takeError();
 921     RuntimeDyldChecker::MemoryRegionInfo SecInfo;
 922     SecInfo.setTargetAddress(Dyld.getSectionLoadAddress(*SectionID));
 923     StringRef SecContent = Dyld.getSectionContent(*SectionID);
 924     SecInfo.setContent(ArrayRef<char>(SecContent.data(), SecContent.size()));
 925     return SecInfo;
 926   };
 927
 928   auto GetStubInfo = [&Dyld, &StubMap](StringRef StubContainer,
 929                                        StringRef SymbolName)
 930       -> Expected<RuntimeDyldChecker::MemoryRegionInfo> {
 931     if (!StubMap.count(StubContainer))
 932       return make_error<StringError>("Stub container not found: " +
 933                                          StubContainer,
 934                                      inconvertibleErrorCode());
 935     if (!StubMap[StubContainer].count(SymbolName))
 936       return make_error<StringError>("Symbol name " + SymbolName +
 937                                          " in stub container " + StubContainer,
 938                                      inconvertibleErrorCode());
 939     auto &SI = StubMap[StubContainer][SymbolName];
 940     RuntimeDyldChecker::MemoryRegionInfo StubMemInfo;
 941     StubMemInfo.setTargetAddress(Dyld.getSectionLoadAddress(SI.SectionID) +
 942                                  SI.Offset);
 943     StringRef SecContent =
 944         Dyld.getSectionContent(SI.SectionID).substr(SI.Offset);
 945     StubMemInfo.setContent(
 946         ArrayRef<char>(SecContent.data(), SecContent.size()));
 947     return StubMemInfo;
 948   };
 949
 950   // We will initialize this below once we have the first object file and can
 951   // know the endianness.
 952   std::unique_ptr<RuntimeDyldChecker> Checker;
 953
 954   // If we don't have any input files, read from stdin.
 955   if (!InputFileList.size())
 956     InputFileList.push_back("-");
 957   for (auto &InputFile : InputFileList) {
 958     // Load the input memory buffer.
 959     ErrorOr<std::unique_ptr<MemoryBuffer>> InputBuffer =
 960         MemoryBuffer::getFileOrSTDIN(InputFile);
 961
 962     if (std::error_code EC = InputBuffer.getError())
 963       ErrorAndExit("unable to read input: '" + EC.message() + "'");
 964
 965     Expected<std::unique_ptr<ObjectFile>> MaybeObj(
 966       ObjectFile::createObjectFile((*InputBuffer)->getMemBufferRef()));
 967
 968     if (!MaybeObj) {
 969       std::string Buf;
 970       raw_string_ostream OS(Buf);
 971       logAllUnhandledErrors(MaybeObj.takeError(), OS);
 972       OS.flush();
 973       ErrorAndExit("unable to create object file: '" + Buf + "'");
 974     }
 975
 976     ObjectFile &Obj = **MaybeObj;
 977
 978     if (!Checker)
 979       Checker = std::make_unique<RuntimeDyldChecker>(
 980           IsSymbolValid, GetSymbolInfo, GetSectionInfo, GetStubInfo,
 981           GetStubInfo,
 982           Obj.isLittleEndian() ? llvm::endianness::little
 983                                : llvm::endianness::big,
 984           TheTriple, MCPU, SubtargetFeatures(), dbgs());
 985
 986     auto FileName = sys::path::filename(InputFile);
 987     MemMgr.setSectionIDsMap(&FileToSecIDMap[FileName]);
 988
 989     // Load the object file
 990     Dyld.loadObject(Obj);
 991     if (Dyld.hasError()) {
 992       ErrorAndExit(Dyld.getErrorString());
 993     }
 994   }
 995
 996   // Re-map the section addresses into the phony target address space and add
 997   // dummy symbols.
 998   applySpecificSectionMappings(Dyld, FileToSecIDMap);
 999   remapSectionsAndSymbols(TheTriple, Dyld, MemMgr);
1000
1001   // Resolve all the relocations we can.
1002   Dyld.resolveRelocations();
1003
1004   // Register EH frames.
1005   Dyld.registerEHFrames();
1006
1007   int ErrorCode = checkAllExpressions(*Checker);
1008   if (Dyld.hasError())
1009     ErrorAndExit("RTDyld reported an error applying relocations:\n  " +
1010                  Dyld.getErrorString());
1011
1012   return ErrorCode;
1013 }
1014
1015 int main(int argc, char **argv) {
1016   InitLLVM X(argc, argv);
1017   ProgramName = argv[0];
1018
1019   llvm::InitializeAllTargetInfos();
1020   llvm::InitializeAllTargetMCs();
1021   llvm::InitializeAllDisassemblers();
1022
1023   cl::HideUnrelatedOptions({&RTDyldCategory, &getColorCategory()});
1024   cl::ParseCommandLineOptions(argc, argv, "llvm MC-JIT tool\n");
1025
1026   ExitOnErr.setBanner(std::string(argv[0]) + ": ");
1027
1028   Timers = ShowTimes ? std::make_unique<RTDyldTimers>() : nullptr;
1029
1030   int Result = 0;
1031   switch (Action) {
1032   case AC_Execute:
1033     Result = executeInput();
1034     break;
1035   case AC_PrintDebugLineInfo:
1036     Result =
1037         printLineInfoForInput(/* LoadObjects */ true, /* UseDebugObj */ true);
1038     break;
1039   case AC_PrintLineInfo:
1040     Result =
1041         printLineInfoForInput(/* LoadObjects */ true, /* UseDebugObj */ false);
1042     break;
1043   case AC_PrintObjectLineInfo:
1044     Result =
1045         printLineInfoForInput(/* LoadObjects */ false, /* UseDebugObj */ false);
1046     break;
1047   case AC_Verify:
1048     Result = linkAndVerify();
1049     break;
1050   }
1051   return Result;
1052 }