lldb/source/Expression/ObjectFileJIT.cpp

   1 //===-- ObjectFileJIT.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/ADT/StringRef.h"
  10
  11 #include "lldb/Core/Module.h"
  12 #include "lldb/Core/ModuleSpec.h"
  13 #include "lldb/Core/PluginManager.h"
  14 #include "lldb/Core/Section.h"
  15 #include "lldb/Expression/ObjectFileJIT.h"
  16 #include "lldb/Target/Process.h"
  17 #include "lldb/Target/SectionLoadList.h"
  18 #include "lldb/Target/Target.h"
  19 #include "lldb/Utility/ArchSpec.h"
  20 #include "lldb/Utility/DataBuffer.h"
  21 #include "lldb/Utility/DataBufferHeap.h"
  22 #include "lldb/Utility/FileSpec.h"
  23 #include "lldb/Utility/FileSpecList.h"
  24 #include "lldb/Utility/Log.h"
  25 #include "lldb/Utility/Timer.h"
  26 #include "lldb/Utility/UUID.h"
  27
  28 using namespace lldb;
  29 using namespace lldb_private;
  30
  31 char ObjectFileJIT::ID;
  32
  33 void ObjectFileJIT::Initialize() {
  34   PluginManager::RegisterPlugin(GetPluginNameStatic(),
  35                                 GetPluginDescriptionStatic(), CreateInstance,
  36                                 CreateMemoryInstance, GetModuleSpecifications);
  37 }
  38
  39 void ObjectFileJIT::Terminate() {
  40   PluginManager::UnregisterPlugin(CreateInstance);
  41 }
  42
  43 ObjectFile *ObjectFileJIT::CreateInstance(const lldb::ModuleSP &module_sp,
  44                                           DataBufferSP data_sp,
  45                                           lldb::offset_t data_offset,
  46                                           const FileSpec *file,
  47                                           lldb::offset_t file_offset,
  48                                           lldb::offset_t length) {
  49   // JIT'ed object file is backed by the ObjectFileJITDelegate, never read from
  50   // a file
  51   return nullptr;
  52 }
  53
  54 ObjectFile *ObjectFileJIT::CreateMemoryInstance(const lldb::ModuleSP &module_sp,
  55                                                 WritableDataBufferSP data_sp,
  56                                                 const ProcessSP &process_sp,
  57                                                 lldb::addr_t header_addr) {
  58   // JIT'ed object file is backed by the ObjectFileJITDelegate, never read from
  59   // memory
  60   return nullptr;
  61 }
  62
  63 size_t ObjectFileJIT::GetModuleSpecifications(
  64     const lldb_private::FileSpec &file, lldb::DataBufferSP &data_sp,
  65     lldb::offset_t data_offset, lldb::offset_t file_offset,
  66     lldb::offset_t length, lldb_private::ModuleSpecList &specs) {
  67   // JIT'ed object file can't be read from a file on disk
  68   return 0;
  69 }
  70
  71 ObjectFileJIT::ObjectFileJIT(const lldb::ModuleSP &module_sp,
  72                              const ObjectFileJITDelegateSP &delegate_sp)
  73     : ObjectFile(module_sp, nullptr, 0, 0, DataBufferSP(), 0), m_delegate_wp() {
  74   if (delegate_sp) {
  75     m_delegate_wp = delegate_sp;
  76     m_data.SetByteOrder(delegate_sp->GetByteOrder());
  77     m_data.SetAddressByteSize(delegate_sp->GetAddressByteSize());
  78   }
  79 }
  80
  81 ObjectFileJIT::~ObjectFileJIT() = default;
  82
  83 bool ObjectFileJIT::ParseHeader() {
  84   // JIT code is never in a file, nor is it required to have any header
  85   return false;
  86 }
  87
  88 ByteOrder ObjectFileJIT::GetByteOrder() const { return m_data.GetByteOrder(); }
  89
  90 bool ObjectFileJIT::IsExecutable() const { return false; }
  91
  92 uint32_t ObjectFileJIT::GetAddressByteSize() const {
  93   return m_data.GetAddressByteSize();
  94 }
  95
  96 void ObjectFileJIT::ParseSymtab(Symtab &symtab) {
  97   ObjectFileJITDelegateSP delegate_sp(m_delegate_wp.lock());
  98   if (delegate_sp)
  99     delegate_sp->PopulateSymtab(this, symtab);
 100 }
 101
 102 bool ObjectFileJIT::IsStripped() {
 103   return false; // JIT code that is in a module is never stripped
 104 }
 105
 106 void ObjectFileJIT::CreateSections(SectionList &unified_section_list) {
 107   if (!m_sections_up) {
 108     m_sections_up = std::make_unique<SectionList>();
 109     ObjectFileJITDelegateSP delegate_sp(m_delegate_wp.lock());
 110     if (delegate_sp) {
 111       delegate_sp->PopulateSectionList(this, *m_sections_up);
 112       unified_section_list = *m_sections_up;
 113     }
 114   }
 115 }
 116
 117 void ObjectFileJIT::Dump(Stream *s) {
 118   ModuleSP module_sp(GetModule());
 119   if (module_sp) {
 120     std::lock_guard<std::recursive_mutex> guard(module_sp->GetMutex());
 121     s->Printf("%p: ", static_cast<void *>(this));
 122     s->Indent();
 123     s->PutCString("ObjectFileJIT");
 124
 125     if (ArchSpec arch = GetArchitecture())
 126       *s << ", arch = " << arch.GetArchitectureName();
 127
 128     s->EOL();
 129
 130     SectionList *sections = GetSectionList();
 131     if (sections)
 132       sections->Dump(s->AsRawOstream(), s->GetIndentLevel(), nullptr, true,
 133                      UINT32_MAX);
 134
 135     if (m_symtab_up)
 136       m_symtab_up->Dump(s, nullptr, eSortOrderNone);
 137   }
 138 }
 139
 140 UUID ObjectFileJIT::GetUUID() {
 141   // TODO: maybe get from delegate, not needed for first pass
 142   return UUID();
 143 }
 144
 145 uint32_t ObjectFileJIT::GetDependentModules(FileSpecList &files) {
 146   // JIT modules don't have dependencies, but they could
 147   // if external functions are called and we know where they are
 148   files.Clear();
 149   return 0;
 150 }
 151
 152 lldb_private::Address ObjectFileJIT::GetEntryPointAddress() {
 153   return Address();
 154 }
 155
 156 lldb_private::Address ObjectFileJIT::GetBaseAddress() { return Address(); }
 157
 158 ObjectFile::Type ObjectFileJIT::CalculateType() { return eTypeJIT; }
 159
 160 ObjectFile::Strata ObjectFileJIT::CalculateStrata() { return eStrataJIT; }
 161
 162 ArchSpec ObjectFileJIT::GetArchitecture() {
 163   if (ObjectFileJITDelegateSP delegate_sp = m_delegate_wp.lock())
 164     return delegate_sp->GetArchitecture();
 165   return ArchSpec();
 166 }
 167
 168 bool ObjectFileJIT::SetLoadAddress(Target &target, lldb::addr_t value,
 169                                    bool value_is_offset) {
 170   size_t num_loaded_sections = 0;
 171   SectionList *section_list = GetSectionList();
 172   if (section_list) {
 173     const size_t num_sections = section_list->GetSize();
 174     // "value" is an offset to apply to each top level segment
 175     for (size_t sect_idx = 0; sect_idx < num_sections; ++sect_idx) {
 176       // Iterate through the object file sections to find all of the sections
 177       // that size on disk (to avoid __PAGEZERO) and load them
 178       SectionSP section_sp(section_list->GetSectionAtIndex(sect_idx));
 179       if (section_sp && section_sp->GetFileSize() > 0 &&
 180           !section_sp->IsThreadSpecific()) {
 181         if (target.GetSectionLoadList().SetSectionLoadAddress(
 182                 section_sp, section_sp->GetFileAddress() + value))
 183           ++num_loaded_sections;
 184       }
 185     }
 186   }
 187   return num_loaded_sections > 0;
 188 }
 189
 190 size_t ObjectFileJIT::ReadSectionData(lldb_private::Section *section,
 191                                       lldb::offset_t section_offset, void *dst,
 192                                       size_t dst_len) {
 193   lldb::offset_t file_size = section->GetFileSize();
 194   if (section_offset < file_size) {
 195     size_t src_len = file_size - section_offset;
 196     if (src_len > dst_len)
 197       src_len = dst_len;
 198     const uint8_t *src =
 199         ((uint8_t *)(uintptr_t)section->GetFileOffset()) + section_offset;
 200
 201     memcpy(dst, src, src_len);
 202     return src_len;
 203   }
 204   return 0;
 205 }
 206
 207 size_t
 208 ObjectFileJIT::ReadSectionData(lldb_private::Section *section,
 209                                lldb_private::DataExtractor &section_data) {
 210   if (section->GetFileSize()) {
 211     const void *src = (void *)(uintptr_t)section->GetFileOffset();
 212
 213     DataBufferSP data_sp =
 214         std::make_shared<DataBufferHeap>(src, section->GetFileSize());
 215     section_data.SetData(data_sp, 0, data_sp->GetByteSize());
 216     section_data.SetByteOrder(GetByteOrder());
 217     section_data.SetAddressByteSize(GetAddressByteSize());
 218     return section_data.GetByteSize();
 219   }
 220   section_data.Clear();
 221   return 0;
 222 }