xref: /freebsd/contrib/llvm-project/llvm/tools/llvm-rtdyld/llvm-rtdyld.cpp (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
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 
dumpFileToSectionIDMap(const FileToSectionIDMap & FileToSecIDMap)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 
getSectionId(const FileToSectionIDMap & FileToSecIDMap,StringRef FileName,StringRef SectionName)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 {
SectionInfoTrivialMemoryManager::SectionInfo192     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.
setSectionIDsMap(SectionIDMap * SecIDMap)213   void setSectionIDsMap(SectionIDMap *SecIDMap) {
214     this->SecIDMap = SecIDMap;
215   }
216 
getPointerToNamedFunction(const std::string & Name,bool AbortOnFailure=true)217   void *getPointerToNamedFunction(const std::string &Name,
218                                   bool AbortOnFailure = true) override {
219     return nullptr;
220   }
221 
finalizeMemory(std::string * ErrMsg)222   bool finalizeMemory(std::string *ErrMsg) override { return false; }
223 
addDummySymbol(const std::string & Name,uint64_t Addr)224   void addDummySymbol(const std::string &Name, uint64_t Addr) {
225     DummyExterns[Name] = Addr;
226   }
227 
findSymbol(const std::string & Name)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 
registerEHFrames(uint8_t * Addr,uint64_t LoadAddr,size_t Size)245   void registerEHFrames(uint8_t *Addr, uint64_t LoadAddr,
246                         size_t Size) override {}
deregisterEHFrames()247   void deregisterEHFrames() override {}
248 
preallocateSlab(uint64_t Size)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 
allocateFromSlab(uintptr_t Size,unsigned Alignment,bool isCode,StringRef SectionName,unsigned SectionID)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 
allocateCodeSection(uintptr_t Size,unsigned Alignment,unsigned SectionID,StringRef SectionName)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 
allocateDataSection(uintptr_t Size,unsigned Alignment,unsigned SectionID,StringRef SectionName,bool IsReadOnly)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
allocateTLSSection(uintptr_t Size,unsigned Alignment,unsigned SectionID,StringRef SectionName)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 
ErrorAndExit(const Twine & Msg)392 static void ErrorAndExit(const Twine &Msg) {
393   errs() << ProgramName << ": error: " << Msg << "\n";
394   exit(1);
395 }
396 
loadDylibs()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 
printLineInfoForInput(bool LoadObjects,bool UseDebugObj)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 
doPreallocation(TrivialMemoryManager & MemMgr)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 
executeInput()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 
checkAllExpressions(RuntimeDyldChecker & Checker)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 
applySpecificSectionMappings(RuntimeDyld & Dyld,const FileToSectionIDMap & FileToSecIDMap)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 //
remapSectionsAndSymbols(const llvm::Triple & TargetTriple,RuntimeDyld & Dyld,TrivialMemoryManager & MemMgr)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.
linkAndVerify()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                                        StringRef KindNameFilter)
931       -> Expected<RuntimeDyldChecker::MemoryRegionInfo> {
932     if (!StubMap.count(StubContainer))
933       return make_error<StringError>("Stub container not found: " +
934                                          StubContainer,
935                                      inconvertibleErrorCode());
936     if (!StubMap[StubContainer].count(SymbolName))
937       return make_error<StringError>("Symbol name " + SymbolName +
938                                          " in stub container " + StubContainer,
939                                      inconvertibleErrorCode());
940     auto &SI = StubMap[StubContainer][SymbolName];
941     RuntimeDyldChecker::MemoryRegionInfo StubMemInfo;
942     StubMemInfo.setTargetAddress(Dyld.getSectionLoadAddress(SI.SectionID) +
943                                  SI.Offset);
944     StringRef SecContent =
945         Dyld.getSectionContent(SI.SectionID).substr(SI.Offset);
946     StubMemInfo.setContent(
947         ArrayRef<char>(SecContent.data(), SecContent.size()));
948     return StubMemInfo;
949   };
950 
951   auto GetGOTInfo = [&GetStubInfo](StringRef StubContainer,
952                                    StringRef SymbolName) {
953     return GetStubInfo(StubContainer, SymbolName, "");
954   };
955 
956   // We will initialize this below once we have the first object file and can
957   // know the endianness.
958   std::unique_ptr<RuntimeDyldChecker> Checker;
959 
960   // If we don't have any input files, read from stdin.
961   if (!InputFileList.size())
962     InputFileList.push_back("-");
963   for (auto &InputFile : InputFileList) {
964     // Load the input memory buffer.
965     ErrorOr<std::unique_ptr<MemoryBuffer>> InputBuffer =
966         MemoryBuffer::getFileOrSTDIN(InputFile);
967 
968     if (std::error_code EC = InputBuffer.getError())
969       ErrorAndExit("unable to read input: '" + EC.message() + "'");
970 
971     Expected<std::unique_ptr<ObjectFile>> MaybeObj(
972       ObjectFile::createObjectFile((*InputBuffer)->getMemBufferRef()));
973 
974     if (!MaybeObj) {
975       std::string Buf;
976       raw_string_ostream OS(Buf);
977       logAllUnhandledErrors(MaybeObj.takeError(), OS);
978       OS.flush();
979       ErrorAndExit("unable to create object file: '" + Buf + "'");
980     }
981 
982     ObjectFile &Obj = **MaybeObj;
983 
984     if (!Checker)
985       Checker = std::make_unique<RuntimeDyldChecker>(
986           IsSymbolValid, GetSymbolInfo, GetSectionInfo, GetStubInfo, GetGOTInfo,
987           Obj.isLittleEndian() ? llvm::endianness::little
988                                : llvm::endianness::big,
989           TheTriple, MCPU, SubtargetFeatures(), dbgs());
990 
991     auto FileName = sys::path::filename(InputFile);
992     MemMgr.setSectionIDsMap(&FileToSecIDMap[FileName]);
993 
994     // Load the object file
995     Dyld.loadObject(Obj);
996     if (Dyld.hasError()) {
997       ErrorAndExit(Dyld.getErrorString());
998     }
999   }
1000 
1001   // Re-map the section addresses into the phony target address space and add
1002   // dummy symbols.
1003   applySpecificSectionMappings(Dyld, FileToSecIDMap);
1004   remapSectionsAndSymbols(TheTriple, Dyld, MemMgr);
1005 
1006   // Resolve all the relocations we can.
1007   Dyld.resolveRelocations();
1008 
1009   // Register EH frames.
1010   Dyld.registerEHFrames();
1011 
1012   int ErrorCode = checkAllExpressions(*Checker);
1013   if (Dyld.hasError())
1014     ErrorAndExit("RTDyld reported an error applying relocations:\n  " +
1015                  Dyld.getErrorString());
1016 
1017   return ErrorCode;
1018 }
1019 
main(int argc,char ** argv)1020 int main(int argc, char **argv) {
1021   InitLLVM X(argc, argv);
1022   ProgramName = argv[0];
1023 
1024   llvm::InitializeAllTargetInfos();
1025   llvm::InitializeAllTargetMCs();
1026   llvm::InitializeAllDisassemblers();
1027 
1028   cl::HideUnrelatedOptions({&RTDyldCategory, &getColorCategory()});
1029   cl::ParseCommandLineOptions(argc, argv, "llvm MC-JIT tool\n");
1030 
1031   ExitOnErr.setBanner(std::string(argv[0]) + ": ");
1032 
1033   Timers = ShowTimes ? std::make_unique<RTDyldTimers>() : nullptr;
1034 
1035   int Result = 0;
1036   switch (Action) {
1037   case AC_Execute:
1038     Result = executeInput();
1039     break;
1040   case AC_PrintDebugLineInfo:
1041     Result =
1042         printLineInfoForInput(/* LoadObjects */ true, /* UseDebugObj */ true);
1043     break;
1044   case AC_PrintLineInfo:
1045     Result =
1046         printLineInfoForInput(/* LoadObjects */ true, /* UseDebugObj */ false);
1047     break;
1048   case AC_PrintObjectLineInfo:
1049     Result =
1050         printLineInfoForInput(/* LoadObjects */ false, /* UseDebugObj */ false);
1051     break;
1052   case AC_Verify:
1053     Result = linkAndVerify();
1054     break;
1055   }
1056   return Result;
1057 }
1058