xref: /freebsd-src/contrib/llvm-project/lldb/source/Expression/IRExecutionUnit.cpp (revision 4824e7fd18a1223177218d4aec1b3c6c5c4a444e)
1 //===-- IRExecutionUnit.cpp -----------------------------------------------===//
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 #include "llvm/ExecutionEngine/ExecutionEngine.h"
10 #include "llvm/ExecutionEngine/ObjectCache.h"
11 #include "llvm/IR/Constants.h"
12 #include "llvm/IR/DiagnosticHandler.h"
13 #include "llvm/IR/DiagnosticInfo.h"
14 #include "llvm/IR/LLVMContext.h"
15 #include "llvm/IR/Module.h"
16 #include "llvm/Support/SourceMgr.h"
17 #include "llvm/Support/raw_ostream.h"
18 
19 #include "lldb/Core/Debugger.h"
20 #include "lldb/Core/Disassembler.h"
21 #include "lldb/Core/Module.h"
22 #include "lldb/Core/Section.h"
23 #include "lldb/Expression/IRExecutionUnit.h"
24 #include "lldb/Symbol/CompileUnit.h"
25 #include "lldb/Symbol/SymbolContext.h"
26 #include "lldb/Symbol/SymbolFile.h"
27 #include "lldb/Symbol/SymbolVendor.h"
28 #include "lldb/Target/ExecutionContext.h"
29 #include "lldb/Target/Language.h"
30 #include "lldb/Target/LanguageRuntime.h"
31 #include "lldb/Target/Target.h"
32 #include "lldb/Utility/DataBufferHeap.h"
33 #include "lldb/Utility/DataExtractor.h"
34 #include "lldb/Utility/LLDBAssert.h"
35 #include "lldb/Utility/Log.h"
36 
37 #include "lldb/../../source/Plugins/ObjectFile/JIT/ObjectFileJIT.h"
38 
39 using namespace lldb_private;
40 
41 IRExecutionUnit::IRExecutionUnit(std::unique_ptr<llvm::LLVMContext> &context_up,
42                                  std::unique_ptr<llvm::Module> &module_up,
43                                  ConstString &name,
44                                  const lldb::TargetSP &target_sp,
45                                  const SymbolContext &sym_ctx,
46                                  std::vector<std::string> &cpu_features)
47     : IRMemoryMap(target_sp), m_context_up(context_up.release()),
48       m_module_up(module_up.release()), m_module(m_module_up.get()),
49       m_cpu_features(cpu_features), m_name(name), m_sym_ctx(sym_ctx),
50       m_did_jit(false), m_function_load_addr(LLDB_INVALID_ADDRESS),
51       m_function_end_load_addr(LLDB_INVALID_ADDRESS),
52       m_reported_allocations(false) {}
53 
54 lldb::addr_t IRExecutionUnit::WriteNow(const uint8_t *bytes, size_t size,
55                                        Status &error) {
56   const bool zero_memory = false;
57   lldb::addr_t allocation_process_addr =
58       Malloc(size, 8, lldb::ePermissionsWritable | lldb::ePermissionsReadable,
59              eAllocationPolicyMirror, zero_memory, error);
60 
61   if (!error.Success())
62     return LLDB_INVALID_ADDRESS;
63 
64   WriteMemory(allocation_process_addr, bytes, size, error);
65 
66   if (!error.Success()) {
67     Status err;
68     Free(allocation_process_addr, err);
69 
70     return LLDB_INVALID_ADDRESS;
71   }
72 
73   if (Log *log =
74           lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS)) {
75     DataBufferHeap my_buffer(size, 0);
76     Status err;
77     ReadMemory(my_buffer.GetBytes(), allocation_process_addr, size, err);
78 
79     if (err.Success()) {
80       DataExtractor my_extractor(my_buffer.GetBytes(), my_buffer.GetByteSize(),
81                                  lldb::eByteOrderBig, 8);
82       my_extractor.PutToLog(log, 0, my_buffer.GetByteSize(),
83                             allocation_process_addr, 16,
84                             DataExtractor::TypeUInt8);
85     }
86   }
87 
88   return allocation_process_addr;
89 }
90 
91 void IRExecutionUnit::FreeNow(lldb::addr_t allocation) {
92   if (allocation == LLDB_INVALID_ADDRESS)
93     return;
94 
95   Status err;
96 
97   Free(allocation, err);
98 }
99 
100 Status IRExecutionUnit::DisassembleFunction(Stream &stream,
101                                             lldb::ProcessSP &process_wp) {
102   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
103 
104   ExecutionContext exe_ctx(process_wp);
105 
106   Status ret;
107 
108   ret.Clear();
109 
110   lldb::addr_t func_local_addr = LLDB_INVALID_ADDRESS;
111   lldb::addr_t func_remote_addr = LLDB_INVALID_ADDRESS;
112 
113   for (JittedFunction &function : m_jitted_functions) {
114     if (function.m_name == m_name) {
115       func_local_addr = function.m_local_addr;
116       func_remote_addr = function.m_remote_addr;
117     }
118   }
119 
120   if (func_local_addr == LLDB_INVALID_ADDRESS) {
121     ret.SetErrorToGenericError();
122     ret.SetErrorStringWithFormat("Couldn't find function %s for disassembly",
123                                  m_name.AsCString());
124     return ret;
125   }
126 
127   LLDB_LOGF(log,
128             "Found function, has local address 0x%" PRIx64
129             " and remote address 0x%" PRIx64,
130             (uint64_t)func_local_addr, (uint64_t)func_remote_addr);
131 
132   std::pair<lldb::addr_t, lldb::addr_t> func_range;
133 
134   func_range = GetRemoteRangeForLocal(func_local_addr);
135 
136   if (func_range.first == 0 && func_range.second == 0) {
137     ret.SetErrorToGenericError();
138     ret.SetErrorStringWithFormat("Couldn't find code range for function %s",
139                                  m_name.AsCString());
140     return ret;
141   }
142 
143   LLDB_LOGF(log, "Function's code range is [0x%" PRIx64 "+0x%" PRIx64 "]",
144             func_range.first, func_range.second);
145 
146   Target *target = exe_ctx.GetTargetPtr();
147   if (!target) {
148     ret.SetErrorToGenericError();
149     ret.SetErrorString("Couldn't find the target");
150     return ret;
151   }
152 
153   lldb::DataBufferSP buffer_sp(new DataBufferHeap(func_range.second, 0));
154 
155   Process *process = exe_ctx.GetProcessPtr();
156   Status err;
157   process->ReadMemory(func_remote_addr, buffer_sp->GetBytes(),
158                       buffer_sp->GetByteSize(), err);
159 
160   if (!err.Success()) {
161     ret.SetErrorToGenericError();
162     ret.SetErrorStringWithFormat("Couldn't read from process: %s",
163                                  err.AsCString("unknown error"));
164     return ret;
165   }
166 
167   ArchSpec arch(target->GetArchitecture());
168 
169   const char *plugin_name = nullptr;
170   const char *flavor_string = nullptr;
171   lldb::DisassemblerSP disassembler_sp =
172       Disassembler::FindPlugin(arch, flavor_string, plugin_name);
173 
174   if (!disassembler_sp) {
175     ret.SetErrorToGenericError();
176     ret.SetErrorStringWithFormat(
177         "Unable to find disassembler plug-in for %s architecture.",
178         arch.GetArchitectureName());
179     return ret;
180   }
181 
182   if (!process) {
183     ret.SetErrorToGenericError();
184     ret.SetErrorString("Couldn't find the process");
185     return ret;
186   }
187 
188   DataExtractor extractor(buffer_sp, process->GetByteOrder(),
189                           target->GetArchitecture().GetAddressByteSize());
190 
191   if (log) {
192     LLDB_LOGF(log, "Function data has contents:");
193     extractor.PutToLog(log, 0, extractor.GetByteSize(), func_remote_addr, 16,
194                        DataExtractor::TypeUInt8);
195   }
196 
197   disassembler_sp->DecodeInstructions(Address(func_remote_addr), extractor, 0,
198                                       UINT32_MAX, false, false);
199 
200   InstructionList &instruction_list = disassembler_sp->GetInstructionList();
201   instruction_list.Dump(&stream, true, true, &exe_ctx);
202   return ret;
203 }
204 
205 namespace {
206 struct IRExecDiagnosticHandler : public llvm::DiagnosticHandler {
207   Status *err;
208   IRExecDiagnosticHandler(Status *err) : err(err) {}
209   bool handleDiagnostics(const llvm::DiagnosticInfo &DI) override {
210     if (DI.getKind() == llvm::DK_SrcMgr) {
211       const auto &DISM = llvm::cast<llvm::DiagnosticInfoSrcMgr>(DI);
212       if (err && err->Success()) {
213         err->SetErrorToGenericError();
214         err->SetErrorStringWithFormat(
215             "Inline assembly error: %s",
216             DISM.getSMDiag().getMessage().str().c_str());
217       }
218       return true;
219     }
220 
221     return false;
222   }
223 };
224 } // namespace
225 
226 void IRExecutionUnit::ReportSymbolLookupError(ConstString name) {
227   m_failed_lookups.push_back(name);
228 }
229 
230 void IRExecutionUnit::GetRunnableInfo(Status &error, lldb::addr_t &func_addr,
231                                       lldb::addr_t &func_end) {
232   lldb::ProcessSP process_sp(GetProcessWP().lock());
233 
234   static std::recursive_mutex s_runnable_info_mutex;
235 
236   func_addr = LLDB_INVALID_ADDRESS;
237   func_end = LLDB_INVALID_ADDRESS;
238 
239   if (!process_sp) {
240     error.SetErrorToGenericError();
241     error.SetErrorString("Couldn't write the JIT compiled code into the "
242                          "process because the process is invalid");
243     return;
244   }
245 
246   if (m_did_jit) {
247     func_addr = m_function_load_addr;
248     func_end = m_function_end_load_addr;
249 
250     return;
251   };
252 
253   std::lock_guard<std::recursive_mutex> guard(s_runnable_info_mutex);
254 
255   m_did_jit = true;
256 
257   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
258 
259   std::string error_string;
260 
261   if (log) {
262     std::string s;
263     llvm::raw_string_ostream oss(s);
264 
265     m_module->print(oss, nullptr);
266 
267     oss.flush();
268 
269     LLDB_LOGF(log, "Module being sent to JIT: \n%s", s.c_str());
270   }
271 
272   m_module_up->getContext().setDiagnosticHandler(
273       std::make_unique<IRExecDiagnosticHandler>(&error));
274 
275   llvm::EngineBuilder builder(std::move(m_module_up));
276   llvm::Triple triple(m_module->getTargetTriple());
277 
278   builder.setEngineKind(llvm::EngineKind::JIT)
279       .setErrorStr(&error_string)
280       .setRelocationModel(triple.isOSBinFormatMachO() ? llvm::Reloc::PIC_
281                                                       : llvm::Reloc::Static)
282       .setMCJITMemoryManager(std::make_unique<MemoryManager>(*this))
283       .setOptLevel(llvm::CodeGenOpt::Less);
284 
285   llvm::StringRef mArch;
286   llvm::StringRef mCPU;
287   llvm::SmallVector<std::string, 0> mAttrs;
288 
289   for (std::string &feature : m_cpu_features)
290     mAttrs.push_back(feature);
291 
292   llvm::TargetMachine *target_machine =
293       builder.selectTarget(triple, mArch, mCPU, mAttrs);
294 
295   m_execution_engine_up.reset(builder.create(target_machine));
296 
297   if (!m_execution_engine_up) {
298     error.SetErrorToGenericError();
299     error.SetErrorStringWithFormat("Couldn't JIT the function: %s",
300                                    error_string.c_str());
301     return;
302   }
303 
304   m_strip_underscore =
305       (m_execution_engine_up->getDataLayout().getGlobalPrefix() == '_');
306 
307   class ObjectDumper : public llvm::ObjectCache {
308   public:
309     void notifyObjectCompiled(const llvm::Module *module,
310                               llvm::MemoryBufferRef object) override {
311       int fd = 0;
312       llvm::SmallVector<char, 256> result_path;
313       std::string object_name_model =
314           "jit-object-" + module->getModuleIdentifier() + "-%%%.o";
315       (void)llvm::sys::fs::createUniqueFile(object_name_model, fd, result_path);
316       llvm::raw_fd_ostream fds(fd, true);
317       fds.write(object.getBufferStart(), object.getBufferSize());
318     }
319 
320     std::unique_ptr<llvm::MemoryBuffer>
321     getObject(const llvm::Module *module) override {
322       // Return nothing - we're just abusing the object-cache mechanism to dump
323       // objects.
324       return nullptr;
325     }
326   };
327 
328   if (process_sp->GetTarget().GetEnableSaveObjects()) {
329     m_object_cache_up = std::make_unique<ObjectDumper>();
330     m_execution_engine_up->setObjectCache(m_object_cache_up.get());
331   }
332 
333   // Make sure we see all sections, including ones that don't have
334   // relocations...
335   m_execution_engine_up->setProcessAllSections(true);
336 
337   m_execution_engine_up->DisableLazyCompilation();
338 
339   for (llvm::Function &function : *m_module) {
340     if (function.isDeclaration() || function.hasPrivateLinkage())
341       continue;
342 
343     const bool external = !function.hasLocalLinkage();
344 
345     void *fun_ptr = m_execution_engine_up->getPointerToFunction(&function);
346 
347     if (!error.Success()) {
348       // We got an error through our callback!
349       return;
350     }
351 
352     if (!fun_ptr) {
353       error.SetErrorToGenericError();
354       error.SetErrorStringWithFormat(
355           "'%s' was in the JITted module but wasn't lowered",
356           function.getName().str().c_str());
357       return;
358     }
359     m_jitted_functions.push_back(JittedFunction(
360         function.getName().str().c_str(), external, reinterpret_cast<uintptr_t>(fun_ptr)));
361   }
362 
363   CommitAllocations(process_sp);
364   ReportAllocations(*m_execution_engine_up);
365 
366   // We have to do this after calling ReportAllocations because for the MCJIT,
367   // getGlobalValueAddress will cause the JIT to perform all relocations.  That
368   // can only be done once, and has to happen after we do the remapping from
369   // local -> remote. That means we don't know the local address of the
370   // Variables, but we don't need that for anything, so that's okay.
371 
372   std::function<void(llvm::GlobalValue &)> RegisterOneValue = [this](
373       llvm::GlobalValue &val) {
374     if (val.hasExternalLinkage() && !val.isDeclaration()) {
375       uint64_t var_ptr_addr =
376           m_execution_engine_up->getGlobalValueAddress(val.getName().str());
377 
378       lldb::addr_t remote_addr = GetRemoteAddressForLocal(var_ptr_addr);
379 
380       // This is a really unfortunae API that sometimes returns local addresses
381       // and sometimes returns remote addresses, based on whether the variable
382       // was relocated during ReportAllocations or not.
383 
384       if (remote_addr == LLDB_INVALID_ADDRESS) {
385         remote_addr = var_ptr_addr;
386       }
387 
388       if (var_ptr_addr != 0)
389         m_jitted_global_variables.push_back(JittedGlobalVariable(
390             val.getName().str().c_str(), LLDB_INVALID_ADDRESS, remote_addr));
391     }
392   };
393 
394   for (llvm::GlobalVariable &global_var : m_module->getGlobalList()) {
395     RegisterOneValue(global_var);
396   }
397 
398   for (llvm::GlobalAlias &global_alias : m_module->getAliasList()) {
399     RegisterOneValue(global_alias);
400   }
401 
402   WriteData(process_sp);
403 
404   if (m_failed_lookups.size()) {
405     StreamString ss;
406 
407     ss.PutCString("Couldn't lookup symbols:\n");
408 
409     bool emitNewLine = false;
410 
411     for (ConstString failed_lookup : m_failed_lookups) {
412       if (emitNewLine)
413         ss.PutCString("\n");
414       emitNewLine = true;
415       ss.PutCString("  ");
416       ss.PutCString(Mangled(failed_lookup).GetDemangledName().GetStringRef());
417     }
418 
419     m_failed_lookups.clear();
420 
421     error.SetErrorString(ss.GetString());
422 
423     return;
424   }
425 
426   m_function_load_addr = LLDB_INVALID_ADDRESS;
427   m_function_end_load_addr = LLDB_INVALID_ADDRESS;
428 
429   for (JittedFunction &jitted_function : m_jitted_functions) {
430     jitted_function.m_remote_addr =
431         GetRemoteAddressForLocal(jitted_function.m_local_addr);
432 
433     if (!m_name.IsEmpty() && jitted_function.m_name == m_name) {
434       AddrRange func_range =
435           GetRemoteRangeForLocal(jitted_function.m_local_addr);
436       m_function_end_load_addr = func_range.first + func_range.second;
437       m_function_load_addr = jitted_function.m_remote_addr;
438     }
439   }
440 
441   if (log) {
442     LLDB_LOGF(log, "Code can be run in the target.");
443 
444     StreamString disassembly_stream;
445 
446     Status err = DisassembleFunction(disassembly_stream, process_sp);
447 
448     if (!err.Success()) {
449       LLDB_LOGF(log, "Couldn't disassemble function : %s",
450                 err.AsCString("unknown error"));
451     } else {
452       LLDB_LOGF(log, "Function disassembly:\n%s", disassembly_stream.GetData());
453     }
454 
455     LLDB_LOGF(log, "Sections: ");
456     for (AllocationRecord &record : m_records) {
457       if (record.m_process_address != LLDB_INVALID_ADDRESS) {
458         record.dump(log);
459 
460         DataBufferHeap my_buffer(record.m_size, 0);
461         Status err;
462         ReadMemory(my_buffer.GetBytes(), record.m_process_address,
463                    record.m_size, err);
464 
465         if (err.Success()) {
466           DataExtractor my_extractor(my_buffer.GetBytes(),
467                                      my_buffer.GetByteSize(),
468                                      lldb::eByteOrderBig, 8);
469           my_extractor.PutToLog(log, 0, my_buffer.GetByteSize(),
470                                 record.m_process_address, 16,
471                                 DataExtractor::TypeUInt8);
472         }
473       } else {
474         record.dump(log);
475 
476         DataExtractor my_extractor((const void *)record.m_host_address,
477                                    record.m_size, lldb::eByteOrderBig, 8);
478         my_extractor.PutToLog(log, 0, record.m_size, record.m_host_address, 16,
479                               DataExtractor::TypeUInt8);
480       }
481     }
482   }
483 
484   func_addr = m_function_load_addr;
485   func_end = m_function_end_load_addr;
486 
487   return;
488 }
489 
490 IRExecutionUnit::~IRExecutionUnit() {
491   m_module_up.reset();
492   m_execution_engine_up.reset();
493   m_context_up.reset();
494 }
495 
496 IRExecutionUnit::MemoryManager::MemoryManager(IRExecutionUnit &parent)
497     : m_default_mm_up(new llvm::SectionMemoryManager()), m_parent(parent) {}
498 
499 IRExecutionUnit::MemoryManager::~MemoryManager() = default;
500 
501 lldb::SectionType IRExecutionUnit::GetSectionTypeFromSectionName(
502     const llvm::StringRef &name, IRExecutionUnit::AllocationKind alloc_kind) {
503   lldb::SectionType sect_type = lldb::eSectionTypeCode;
504   switch (alloc_kind) {
505   case AllocationKind::Stub:
506     sect_type = lldb::eSectionTypeCode;
507     break;
508   case AllocationKind::Code:
509     sect_type = lldb::eSectionTypeCode;
510     break;
511   case AllocationKind::Data:
512     sect_type = lldb::eSectionTypeData;
513     break;
514   case AllocationKind::Global:
515     sect_type = lldb::eSectionTypeData;
516     break;
517   case AllocationKind::Bytes:
518     sect_type = lldb::eSectionTypeOther;
519     break;
520   }
521 
522   if (!name.empty()) {
523     if (name.equals("__text") || name.equals(".text"))
524       sect_type = lldb::eSectionTypeCode;
525     else if (name.equals("__data") || name.equals(".data"))
526       sect_type = lldb::eSectionTypeCode;
527     else if (name.startswith("__debug_") || name.startswith(".debug_")) {
528       const uint32_t name_idx = name[0] == '_' ? 8 : 7;
529       llvm::StringRef dwarf_name(name.substr(name_idx));
530       switch (dwarf_name[0]) {
531       case 'a':
532         if (dwarf_name.equals("abbrev"))
533           sect_type = lldb::eSectionTypeDWARFDebugAbbrev;
534         else if (dwarf_name.equals("aranges"))
535           sect_type = lldb::eSectionTypeDWARFDebugAranges;
536         else if (dwarf_name.equals("addr"))
537           sect_type = lldb::eSectionTypeDWARFDebugAddr;
538         break;
539 
540       case 'f':
541         if (dwarf_name.equals("frame"))
542           sect_type = lldb::eSectionTypeDWARFDebugFrame;
543         break;
544 
545       case 'i':
546         if (dwarf_name.equals("info"))
547           sect_type = lldb::eSectionTypeDWARFDebugInfo;
548         break;
549 
550       case 'l':
551         if (dwarf_name.equals("line"))
552           sect_type = lldb::eSectionTypeDWARFDebugLine;
553         else if (dwarf_name.equals("loc"))
554           sect_type = lldb::eSectionTypeDWARFDebugLoc;
555         else if (dwarf_name.equals("loclists"))
556           sect_type = lldb::eSectionTypeDWARFDebugLocLists;
557         break;
558 
559       case 'm':
560         if (dwarf_name.equals("macinfo"))
561           sect_type = lldb::eSectionTypeDWARFDebugMacInfo;
562         break;
563 
564       case 'p':
565         if (dwarf_name.equals("pubnames"))
566           sect_type = lldb::eSectionTypeDWARFDebugPubNames;
567         else if (dwarf_name.equals("pubtypes"))
568           sect_type = lldb::eSectionTypeDWARFDebugPubTypes;
569         break;
570 
571       case 's':
572         if (dwarf_name.equals("str"))
573           sect_type = lldb::eSectionTypeDWARFDebugStr;
574         else if (dwarf_name.equals("str_offsets"))
575           sect_type = lldb::eSectionTypeDWARFDebugStrOffsets;
576         break;
577 
578       case 'r':
579         if (dwarf_name.equals("ranges"))
580           sect_type = lldb::eSectionTypeDWARFDebugRanges;
581         break;
582 
583       default:
584         break;
585       }
586     } else if (name.startswith("__apple_") || name.startswith(".apple_"))
587       sect_type = lldb::eSectionTypeInvalid;
588     else if (name.equals("__objc_imageinfo"))
589       sect_type = lldb::eSectionTypeOther;
590   }
591   return sect_type;
592 }
593 
594 uint8_t *IRExecutionUnit::MemoryManager::allocateCodeSection(
595     uintptr_t Size, unsigned Alignment, unsigned SectionID,
596     llvm::StringRef SectionName) {
597   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
598 
599   uint8_t *return_value = m_default_mm_up->allocateCodeSection(
600       Size, Alignment, SectionID, SectionName);
601 
602   m_parent.m_records.push_back(AllocationRecord(
603       (uintptr_t)return_value,
604       lldb::ePermissionsReadable | lldb::ePermissionsExecutable,
605       GetSectionTypeFromSectionName(SectionName, AllocationKind::Code), Size,
606       Alignment, SectionID, SectionName.str().c_str()));
607 
608   LLDB_LOGF(log,
609             "IRExecutionUnit::allocateCodeSection(Size=0x%" PRIx64
610             ", Alignment=%u, SectionID=%u) = %p",
611             (uint64_t)Size, Alignment, SectionID, (void *)return_value);
612 
613   if (m_parent.m_reported_allocations) {
614     Status err;
615     lldb::ProcessSP process_sp =
616         m_parent.GetBestExecutionContextScope()->CalculateProcess();
617 
618     m_parent.CommitOneAllocation(process_sp, err, m_parent.m_records.back());
619   }
620 
621   return return_value;
622 }
623 
624 uint8_t *IRExecutionUnit::MemoryManager::allocateDataSection(
625     uintptr_t Size, unsigned Alignment, unsigned SectionID,
626     llvm::StringRef SectionName, bool IsReadOnly) {
627   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
628 
629   uint8_t *return_value = m_default_mm_up->allocateDataSection(
630       Size, Alignment, SectionID, SectionName, IsReadOnly);
631 
632   uint32_t permissions = lldb::ePermissionsReadable;
633   if (!IsReadOnly)
634     permissions |= lldb::ePermissionsWritable;
635   m_parent.m_records.push_back(AllocationRecord(
636       (uintptr_t)return_value, permissions,
637       GetSectionTypeFromSectionName(SectionName, AllocationKind::Data), Size,
638       Alignment, SectionID, SectionName.str().c_str()));
639   LLDB_LOGF(log,
640             "IRExecutionUnit::allocateDataSection(Size=0x%" PRIx64
641             ", Alignment=%u, SectionID=%u) = %p",
642             (uint64_t)Size, Alignment, SectionID, (void *)return_value);
643 
644   if (m_parent.m_reported_allocations) {
645     Status err;
646     lldb::ProcessSP process_sp =
647         m_parent.GetBestExecutionContextScope()->CalculateProcess();
648 
649     m_parent.CommitOneAllocation(process_sp, err, m_parent.m_records.back());
650   }
651 
652   return return_value;
653 }
654 
655 void IRExecutionUnit::CollectCandidateCNames(std::vector<ConstString> &C_names,
656                                              ConstString name) {
657   if (m_strip_underscore && name.AsCString()[0] == '_')
658     C_names.insert(C_names.begin(), ConstString(&name.AsCString()[1]));
659   C_names.push_back(name);
660 }
661 
662 void IRExecutionUnit::CollectCandidateCPlusPlusNames(
663     std::vector<ConstString> &CPP_names,
664     const std::vector<ConstString> &C_names, const SymbolContext &sc) {
665   if (auto *cpp_lang = Language::FindPlugin(lldb::eLanguageTypeC_plus_plus)) {
666     for (const ConstString &name : C_names) {
667       Mangled mangled(name);
668       if (cpp_lang->SymbolNameFitsToLanguage(mangled)) {
669         if (ConstString best_alternate =
670                 cpp_lang->FindBestAlternateFunctionMangledName(mangled, sc)) {
671           CPP_names.push_back(best_alternate);
672         }
673       }
674 
675       std::vector<ConstString> alternates =
676           cpp_lang->GenerateAlternateFunctionManglings(name);
677       CPP_names.insert(CPP_names.end(), alternates.begin(), alternates.end());
678 
679       // As a last-ditch fallback, try the base name for C++ names.  It's
680       // terrible, but the DWARF doesn't always encode "extern C" correctly.
681       ConstString basename =
682           cpp_lang->GetDemangledFunctionNameWithoutArguments(mangled);
683       CPP_names.push_back(basename);
684     }
685   }
686 }
687 
688 class LoadAddressResolver {
689 public:
690   LoadAddressResolver(Target *target, bool &symbol_was_missing_weak)
691       : m_target(target), m_symbol_was_missing_weak(symbol_was_missing_weak) {}
692 
693   llvm::Optional<lldb::addr_t> Resolve(SymbolContextList &sc_list) {
694     if (sc_list.IsEmpty())
695       return llvm::None;
696 
697     lldb::addr_t load_address = LLDB_INVALID_ADDRESS;
698 
699     // Missing_weak_symbol will be true only if we found only weak undefined
700     // references to this symbol.
701     m_symbol_was_missing_weak = true;
702 
703     for (auto candidate_sc : sc_list.SymbolContexts()) {
704       // Only symbols can be weak undefined.
705       if (!candidate_sc.symbol ||
706           candidate_sc.symbol->GetType() != lldb::eSymbolTypeUndefined ||
707           !candidate_sc.symbol->IsWeak())
708         m_symbol_was_missing_weak = false;
709 
710       // First try the symbol.
711       if (candidate_sc.symbol) {
712         load_address = candidate_sc.symbol->ResolveCallableAddress(*m_target);
713         if (load_address == LLDB_INVALID_ADDRESS) {
714           Address addr = candidate_sc.symbol->GetAddress();
715           load_address = m_target->GetProcessSP()
716                              ? addr.GetLoadAddress(m_target)
717                              : addr.GetFileAddress();
718         }
719       }
720 
721       // If that didn't work, try the function.
722       if (load_address == LLDB_INVALID_ADDRESS && candidate_sc.function) {
723         Address addr =
724             candidate_sc.function->GetAddressRange().GetBaseAddress();
725         load_address = m_target->GetProcessSP() ? addr.GetLoadAddress(m_target)
726                                                 : addr.GetFileAddress();
727       }
728 
729       // We found a load address.
730       if (load_address != LLDB_INVALID_ADDRESS) {
731         // If the load address is external, we're done.
732         const bool is_external =
733             (candidate_sc.function) ||
734             (candidate_sc.symbol && candidate_sc.symbol->IsExternal());
735         if (is_external)
736           return load_address;
737 
738         // Otherwise, remember the best internal load address.
739         if (m_best_internal_load_address == LLDB_INVALID_ADDRESS)
740           m_best_internal_load_address = load_address;
741       }
742     }
743 
744     // You test the address of a weak symbol against NULL to see if it is
745     // present. So we should return 0 for a missing weak symbol.
746     if (m_symbol_was_missing_weak)
747       return 0;
748 
749     return llvm::None;
750   }
751 
752   lldb::addr_t GetBestInternalLoadAddress() const {
753     return m_best_internal_load_address;
754   }
755 
756 private:
757   Target *m_target;
758   bool &m_symbol_was_missing_weak;
759   lldb::addr_t m_best_internal_load_address = LLDB_INVALID_ADDRESS;
760 };
761 
762 lldb::addr_t
763 IRExecutionUnit::FindInSymbols(const std::vector<ConstString> &names,
764                                const lldb_private::SymbolContext &sc,
765                                bool &symbol_was_missing_weak) {
766   symbol_was_missing_weak = false;
767 
768   Target *target = sc.target_sp.get();
769   if (!target) {
770     // We shouldn't be doing any symbol lookup at all without a target.
771     return LLDB_INVALID_ADDRESS;
772   }
773 
774   LoadAddressResolver resolver(target, symbol_was_missing_weak);
775 
776   ModuleFunctionSearchOptions function_options;
777   function_options.include_symbols = true;
778   function_options.include_inlines = false;
779 
780   for (const ConstString &name : names) {
781     if (sc.module_sp) {
782       SymbolContextList sc_list;
783       sc.module_sp->FindFunctions(name, CompilerDeclContext(),
784                                   lldb::eFunctionNameTypeFull, function_options,
785                                   sc_list);
786       if (auto load_addr = resolver.Resolve(sc_list))
787         return *load_addr;
788     }
789 
790     if (sc.target_sp) {
791       SymbolContextList sc_list;
792       sc.target_sp->GetImages().FindFunctions(name, lldb::eFunctionNameTypeFull,
793                                               function_options, sc_list);
794       if (auto load_addr = resolver.Resolve(sc_list))
795         return *load_addr;
796     }
797 
798     if (sc.target_sp) {
799       SymbolContextList sc_list;
800       sc.target_sp->GetImages().FindSymbolsWithNameAndType(
801           name, lldb::eSymbolTypeAny, sc_list);
802       if (auto load_addr = resolver.Resolve(sc_list))
803         return *load_addr;
804     }
805 
806     lldb::addr_t best_internal_load_address =
807         resolver.GetBestInternalLoadAddress();
808     if (best_internal_load_address != LLDB_INVALID_ADDRESS)
809       return best_internal_load_address;
810   }
811 
812   return LLDB_INVALID_ADDRESS;
813 }
814 
815 lldb::addr_t
816 IRExecutionUnit::FindInRuntimes(const std::vector<ConstString> &names,
817                                 const lldb_private::SymbolContext &sc) {
818   lldb::TargetSP target_sp = sc.target_sp;
819 
820   if (!target_sp) {
821     return LLDB_INVALID_ADDRESS;
822   }
823 
824   lldb::ProcessSP process_sp = sc.target_sp->GetProcessSP();
825 
826   if (!process_sp) {
827     return LLDB_INVALID_ADDRESS;
828   }
829 
830   for (const ConstString &name : names) {
831     for (LanguageRuntime *runtime : process_sp->GetLanguageRuntimes()) {
832       lldb::addr_t symbol_load_addr = runtime->LookupRuntimeSymbol(name);
833 
834       if (symbol_load_addr != LLDB_INVALID_ADDRESS)
835         return symbol_load_addr;
836     }
837   }
838 
839   return LLDB_INVALID_ADDRESS;
840 }
841 
842 lldb::addr_t IRExecutionUnit::FindInUserDefinedSymbols(
843     const std::vector<ConstString> &names,
844     const lldb_private::SymbolContext &sc) {
845   lldb::TargetSP target_sp = sc.target_sp;
846 
847   for (const ConstString &name : names) {
848     lldb::addr_t symbol_load_addr = target_sp->GetPersistentSymbol(name);
849 
850     if (symbol_load_addr != LLDB_INVALID_ADDRESS)
851       return symbol_load_addr;
852   }
853 
854   return LLDB_INVALID_ADDRESS;
855 }
856 
857 lldb::addr_t IRExecutionUnit::FindSymbol(lldb_private::ConstString name,
858                                          bool &missing_weak) {
859   std::vector<ConstString> candidate_C_names;
860   std::vector<ConstString> candidate_CPlusPlus_names;
861 
862   CollectCandidateCNames(candidate_C_names, name);
863 
864   lldb::addr_t ret = FindInSymbols(candidate_C_names, m_sym_ctx, missing_weak);
865   if (ret != LLDB_INVALID_ADDRESS)
866     return ret;
867 
868   // If we find the symbol in runtimes or user defined symbols it can't be
869   // a missing weak symbol.
870   missing_weak = false;
871   ret = FindInRuntimes(candidate_C_names, m_sym_ctx);
872   if (ret != LLDB_INVALID_ADDRESS)
873     return ret;
874 
875   ret = FindInUserDefinedSymbols(candidate_C_names, m_sym_ctx);
876   if (ret != LLDB_INVALID_ADDRESS)
877     return ret;
878 
879   CollectCandidateCPlusPlusNames(candidate_CPlusPlus_names, candidate_C_names,
880                                  m_sym_ctx);
881   ret = FindInSymbols(candidate_CPlusPlus_names, m_sym_ctx, missing_weak);
882   return ret;
883 }
884 
885 void IRExecutionUnit::GetStaticInitializers(
886     std::vector<lldb::addr_t> &static_initializers) {
887   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
888 
889   llvm::GlobalVariable *global_ctors =
890       m_module->getNamedGlobal("llvm.global_ctors");
891   if (!global_ctors) {
892     LLDB_LOG(log, "Couldn't find llvm.global_ctors.");
893     return;
894   }
895   auto *ctor_array =
896       llvm::dyn_cast<llvm::ConstantArray>(global_ctors->getInitializer());
897   if (!ctor_array) {
898     LLDB_LOG(log, "llvm.global_ctors not a ConstantArray.");
899     return;
900   }
901 
902   for (llvm::Use &ctor_use : ctor_array->operands()) {
903     auto *ctor_struct = llvm::dyn_cast<llvm::ConstantStruct>(ctor_use);
904     if (!ctor_struct)
905       continue;
906     // this is standardized
907     lldbassert(ctor_struct->getNumOperands() == 3);
908     auto *ctor_function =
909         llvm::dyn_cast<llvm::Function>(ctor_struct->getOperand(1));
910     if (!ctor_function) {
911       LLDB_LOG(log, "global_ctor doesn't contain an llvm::Function");
912       continue;
913     }
914 
915     ConstString ctor_function_name(ctor_function->getName().str());
916     LLDB_LOG(log, "Looking for callable jitted function with name {0}.",
917              ctor_function_name);
918 
919     for (JittedFunction &jitted_function : m_jitted_functions) {
920       if (ctor_function_name != jitted_function.m_name)
921         continue;
922       if (jitted_function.m_remote_addr == LLDB_INVALID_ADDRESS) {
923         LLDB_LOG(log, "Found jitted function with invalid address.");
924         continue;
925       }
926       static_initializers.push_back(jitted_function.m_remote_addr);
927       LLDB_LOG(log, "Calling function at address {0:x}.",
928                jitted_function.m_remote_addr);
929       break;
930     }
931   }
932 }
933 
934 llvm::JITSymbol
935 IRExecutionUnit::MemoryManager::findSymbol(const std::string &Name) {
936     bool missing_weak = false;
937     uint64_t addr = GetSymbolAddressAndPresence(Name, missing_weak);
938     // This is a weak symbol:
939     if (missing_weak)
940       return llvm::JITSymbol(addr,
941           llvm::JITSymbolFlags::Exported | llvm::JITSymbolFlags::Weak);
942     else
943       return llvm::JITSymbol(addr, llvm::JITSymbolFlags::Exported);
944 }
945 
946 uint64_t
947 IRExecutionUnit::MemoryManager::getSymbolAddress(const std::string &Name) {
948   bool missing_weak = false;
949   return GetSymbolAddressAndPresence(Name, missing_weak);
950 }
951 
952 uint64_t
953 IRExecutionUnit::MemoryManager::GetSymbolAddressAndPresence(
954     const std::string &Name, bool &missing_weak) {
955   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
956 
957   ConstString name_cs(Name.c_str());
958 
959   lldb::addr_t ret = m_parent.FindSymbol(name_cs, missing_weak);
960 
961   if (ret == LLDB_INVALID_ADDRESS) {
962     LLDB_LOGF(log,
963               "IRExecutionUnit::getSymbolAddress(Name=\"%s\") = <not found>",
964               Name.c_str());
965 
966     m_parent.ReportSymbolLookupError(name_cs);
967     return 0;
968   } else {
969     LLDB_LOGF(log, "IRExecutionUnit::getSymbolAddress(Name=\"%s\") = %" PRIx64,
970               Name.c_str(), ret);
971     return ret;
972   }
973 }
974 
975 void *IRExecutionUnit::MemoryManager::getPointerToNamedFunction(
976     const std::string &Name, bool AbortOnFailure) {
977   return (void *)getSymbolAddress(Name);
978 }
979 
980 lldb::addr_t
981 IRExecutionUnit::GetRemoteAddressForLocal(lldb::addr_t local_address) {
982   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
983 
984   for (AllocationRecord &record : m_records) {
985     if (local_address >= record.m_host_address &&
986         local_address < record.m_host_address + record.m_size) {
987       if (record.m_process_address == LLDB_INVALID_ADDRESS)
988         return LLDB_INVALID_ADDRESS;
989 
990       lldb::addr_t ret =
991           record.m_process_address + (local_address - record.m_host_address);
992 
993       LLDB_LOGF(log,
994                 "IRExecutionUnit::GetRemoteAddressForLocal() found 0x%" PRIx64
995                 " in [0x%" PRIx64 "..0x%" PRIx64 "], and returned 0x%" PRIx64
996                 " from [0x%" PRIx64 "..0x%" PRIx64 "].",
997                 local_address, (uint64_t)record.m_host_address,
998                 (uint64_t)record.m_host_address + (uint64_t)record.m_size, ret,
999                 record.m_process_address,
1000                 record.m_process_address + record.m_size);
1001 
1002       return ret;
1003     }
1004   }
1005 
1006   return LLDB_INVALID_ADDRESS;
1007 }
1008 
1009 IRExecutionUnit::AddrRange
1010 IRExecutionUnit::GetRemoteRangeForLocal(lldb::addr_t local_address) {
1011   for (AllocationRecord &record : m_records) {
1012     if (local_address >= record.m_host_address &&
1013         local_address < record.m_host_address + record.m_size) {
1014       if (record.m_process_address == LLDB_INVALID_ADDRESS)
1015         return AddrRange(0, 0);
1016 
1017       return AddrRange(record.m_process_address, record.m_size);
1018     }
1019   }
1020 
1021   return AddrRange(0, 0);
1022 }
1023 
1024 bool IRExecutionUnit::CommitOneAllocation(lldb::ProcessSP &process_sp,
1025                                           Status &error,
1026                                           AllocationRecord &record) {
1027   if (record.m_process_address != LLDB_INVALID_ADDRESS) {
1028     return true;
1029   }
1030 
1031   switch (record.m_sect_type) {
1032   case lldb::eSectionTypeInvalid:
1033   case lldb::eSectionTypeDWARFDebugAbbrev:
1034   case lldb::eSectionTypeDWARFDebugAddr:
1035   case lldb::eSectionTypeDWARFDebugAranges:
1036   case lldb::eSectionTypeDWARFDebugCuIndex:
1037   case lldb::eSectionTypeDWARFDebugFrame:
1038   case lldb::eSectionTypeDWARFDebugInfo:
1039   case lldb::eSectionTypeDWARFDebugLine:
1040   case lldb::eSectionTypeDWARFDebugLoc:
1041   case lldb::eSectionTypeDWARFDebugLocLists:
1042   case lldb::eSectionTypeDWARFDebugMacInfo:
1043   case lldb::eSectionTypeDWARFDebugPubNames:
1044   case lldb::eSectionTypeDWARFDebugPubTypes:
1045   case lldb::eSectionTypeDWARFDebugRanges:
1046   case lldb::eSectionTypeDWARFDebugStr:
1047   case lldb::eSectionTypeDWARFDebugStrOffsets:
1048   case lldb::eSectionTypeDWARFAppleNames:
1049   case lldb::eSectionTypeDWARFAppleTypes:
1050   case lldb::eSectionTypeDWARFAppleNamespaces:
1051   case lldb::eSectionTypeDWARFAppleObjC:
1052   case lldb::eSectionTypeDWARFGNUDebugAltLink:
1053     error.Clear();
1054     break;
1055   default:
1056     const bool zero_memory = false;
1057     record.m_process_address =
1058         Malloc(record.m_size, record.m_alignment, record.m_permissions,
1059                eAllocationPolicyProcessOnly, zero_memory, error);
1060     break;
1061   }
1062 
1063   return error.Success();
1064 }
1065 
1066 bool IRExecutionUnit::CommitAllocations(lldb::ProcessSP &process_sp) {
1067   bool ret = true;
1068 
1069   lldb_private::Status err;
1070 
1071   for (AllocationRecord &record : m_records) {
1072     ret = CommitOneAllocation(process_sp, err, record);
1073 
1074     if (!ret) {
1075       break;
1076     }
1077   }
1078 
1079   if (!ret) {
1080     for (AllocationRecord &record : m_records) {
1081       if (record.m_process_address != LLDB_INVALID_ADDRESS) {
1082         Free(record.m_process_address, err);
1083         record.m_process_address = LLDB_INVALID_ADDRESS;
1084       }
1085     }
1086   }
1087 
1088   return ret;
1089 }
1090 
1091 void IRExecutionUnit::ReportAllocations(llvm::ExecutionEngine &engine) {
1092   m_reported_allocations = true;
1093 
1094   for (AllocationRecord &record : m_records) {
1095     if (record.m_process_address == LLDB_INVALID_ADDRESS)
1096       continue;
1097 
1098     if (record.m_section_id == eSectionIDInvalid)
1099       continue;
1100 
1101     engine.mapSectionAddress((void *)record.m_host_address,
1102                              record.m_process_address);
1103   }
1104 
1105   // Trigger re-application of relocations.
1106   engine.finalizeObject();
1107 }
1108 
1109 bool IRExecutionUnit::WriteData(lldb::ProcessSP &process_sp) {
1110   bool wrote_something = false;
1111   for (AllocationRecord &record : m_records) {
1112     if (record.m_process_address != LLDB_INVALID_ADDRESS) {
1113       lldb_private::Status err;
1114       WriteMemory(record.m_process_address, (uint8_t *)record.m_host_address,
1115                   record.m_size, err);
1116       if (err.Success())
1117         wrote_something = true;
1118     }
1119   }
1120   return wrote_something;
1121 }
1122 
1123 void IRExecutionUnit::AllocationRecord::dump(Log *log) {
1124   if (!log)
1125     return;
1126 
1127   LLDB_LOGF(log,
1128             "[0x%llx+0x%llx]->0x%llx (alignment %d, section ID %d, name %s)",
1129             (unsigned long long)m_host_address, (unsigned long long)m_size,
1130             (unsigned long long)m_process_address, (unsigned)m_alignment,
1131             (unsigned)m_section_id, m_name.c_str());
1132 }
1133 
1134 lldb::ByteOrder IRExecutionUnit::GetByteOrder() const {
1135   ExecutionContext exe_ctx(GetBestExecutionContextScope());
1136   return exe_ctx.GetByteOrder();
1137 }
1138 
1139 uint32_t IRExecutionUnit::GetAddressByteSize() const {
1140   ExecutionContext exe_ctx(GetBestExecutionContextScope());
1141   return exe_ctx.GetAddressByteSize();
1142 }
1143 
1144 void IRExecutionUnit::PopulateSymtab(lldb_private::ObjectFile *obj_file,
1145                                      lldb_private::Symtab &symtab) {
1146   // No symbols yet...
1147 }
1148 
1149 void IRExecutionUnit::PopulateSectionList(
1150     lldb_private::ObjectFile *obj_file,
1151     lldb_private::SectionList &section_list) {
1152   for (AllocationRecord &record : m_records) {
1153     if (record.m_size > 0) {
1154       lldb::SectionSP section_sp(new lldb_private::Section(
1155           obj_file->GetModule(), obj_file, record.m_section_id,
1156           ConstString(record.m_name), record.m_sect_type,
1157           record.m_process_address, record.m_size,
1158           record.m_host_address, // file_offset (which is the host address for
1159                                  // the data)
1160           record.m_size,         // file_size
1161           0,
1162           record.m_permissions)); // flags
1163       section_list.AddSection(section_sp);
1164     }
1165   }
1166 }
1167 
1168 ArchSpec IRExecutionUnit::GetArchitecture() {
1169   ExecutionContext exe_ctx(GetBestExecutionContextScope());
1170   if(Target *target = exe_ctx.GetTargetPtr())
1171     return target->GetArchitecture();
1172   return ArchSpec();
1173 }
1174 
1175 lldb::ModuleSP IRExecutionUnit::GetJITModule() {
1176   ExecutionContext exe_ctx(GetBestExecutionContextScope());
1177   Target *target = exe_ctx.GetTargetPtr();
1178   if (!target)
1179     return nullptr;
1180 
1181   auto Delegate = std::static_pointer_cast<lldb_private::ObjectFileJITDelegate>(
1182       shared_from_this());
1183 
1184   lldb::ModuleSP jit_module_sp =
1185       lldb_private::Module::CreateModuleFromObjectFile<ObjectFileJIT>(Delegate);
1186   if (!jit_module_sp)
1187     return nullptr;
1188 
1189   bool changed = false;
1190   jit_module_sp->SetLoadAddress(*target, 0, true, changed);
1191   return jit_module_sp;
1192 }
1193