ObjectFileJIT.cpp revision 353358 
1//===-- ObjectFileJIT.cpp ---------------------------------------*- C++ -*-===//
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 "ObjectFileJIT.h"
12#include "lldb/Core/Debugger.h"
13#include "lldb/Core/FileSpecList.h"
14#include "lldb/Core/Module.h"
15#include "lldb/Core/ModuleSpec.h"
16#include "lldb/Core/PluginManager.h"
17#include "lldb/Core/Section.h"
18#include "lldb/Core/StreamFile.h"
19#include "lldb/Host/Host.h"
20#include "lldb/Symbol/ObjectFile.h"
21#include "lldb/Target/Platform.h"
22#include "lldb/Target/Process.h"
23#include "lldb/Target/SectionLoadList.h"
24#include "lldb/Target/Target.h"
25#include "lldb/Utility/ArchSpec.h"
26#include "lldb/Utility/DataBuffer.h"
27#include "lldb/Utility/DataBufferHeap.h"
28#include "lldb/Utility/FileSpec.h"
29#include "lldb/Utility/Log.h"
30#include "lldb/Utility/RangeMap.h"
31#include "lldb/Utility/StreamString.h"
32#include "lldb/Utility/Timer.h"
33#include "lldb/Utility/UUID.h"
34
35#ifndef __APPLE__
36#include "Utility/UuidCompatibility.h"
37#endif
38
39using namespace lldb;
40using namespace lldb_private;
41
42void ObjectFileJIT::Initialize() {
43  PluginManager::RegisterPlugin(GetPluginNameStatic(),
44                                GetPluginDescriptionStatic(), CreateInstance,
45                                CreateMemoryInstance, GetModuleSpecifications);
46}
47
48void ObjectFileJIT::Terminate() {
49  PluginManager::UnregisterPlugin(CreateInstance);
50}
51
52lldb_private::ConstString ObjectFileJIT::GetPluginNameStatic() {
53  static ConstString g_name("jit");
54  return g_name;
55}
56
57const char *ObjectFileJIT::GetPluginDescriptionStatic() {
58  return "JIT code object file";
59}
60
61ObjectFile *ObjectFileJIT::CreateInstance(const lldb::ModuleSP &module_sp,
62                                          DataBufferSP &data_sp,
63                                          lldb::offset_t data_offset,
64                                          const FileSpec *file,
65                                          lldb::offset_t file_offset,
66                                          lldb::offset_t length) {
67  // JIT'ed object file is backed by the ObjectFileJITDelegate, never read from
68  // a file
69  return nullptr;
70}
71
72ObjectFile *ObjectFileJIT::CreateMemoryInstance(const lldb::ModuleSP &module_sp,
73                                                DataBufferSP &data_sp,
74                                                const ProcessSP &process_sp,
75                                                lldb::addr_t header_addr) {
76  // JIT'ed object file is backed by the ObjectFileJITDelegate, never read from
77  // memory
78  return nullptr;
79}
80
81size_t ObjectFileJIT::GetModuleSpecifications(
82    const lldb_private::FileSpec &file, lldb::DataBufferSP &data_sp,
83    lldb::offset_t data_offset, lldb::offset_t file_offset,
84    lldb::offset_t length, lldb_private::ModuleSpecList &specs) {
85  // JIT'ed object file can't be read from a file on disk
86  return 0;
87}
88
89ObjectFileJIT::ObjectFileJIT(const lldb::ModuleSP &module_sp,
90                             const ObjectFileJITDelegateSP &delegate_sp)
91    : ObjectFile(module_sp, nullptr, 0, 0, DataBufferSP(), 0), m_delegate_wp() {
92  if (delegate_sp) {
93    m_delegate_wp = delegate_sp;
94    m_data.SetByteOrder(delegate_sp->GetByteOrder());
95    m_data.SetAddressByteSize(delegate_sp->GetAddressByteSize());
96  }
97}
98
99ObjectFileJIT::~ObjectFileJIT() {}
100
101bool ObjectFileJIT::ParseHeader() {
102  // JIT code is never in a file, nor is it required to have any header
103  return false;
104}
105
106ByteOrder ObjectFileJIT::GetByteOrder() const { return m_data.GetByteOrder(); }
107
108bool ObjectFileJIT::IsExecutable() const { return false; }
109
110uint32_t ObjectFileJIT::GetAddressByteSize() const {
111  return m_data.GetAddressByteSize();
112}
113
114Symtab *ObjectFileJIT::GetSymtab() {
115  ModuleSP module_sp(GetModule());
116  if (module_sp) {
117    std::lock_guard<std::recursive_mutex> guard(module_sp->GetMutex());
118    if (m_symtab_up == nullptr) {
119      m_symtab_up.reset(new Symtab(this));
120      std::lock_guard<std::recursive_mutex> symtab_guard(
121          m_symtab_up->GetMutex());
122      ObjectFileJITDelegateSP delegate_sp(m_delegate_wp.lock());
123      if (delegate_sp)
124        delegate_sp->PopulateSymtab(this, *m_symtab_up);
125      // TODO: get symbols from delegate
126      m_symtab_up->Finalize();
127    }
128  }
129  return m_symtab_up.get();
130}
131
132bool ObjectFileJIT::IsStripped() {
133  return false; // JIT code that is in a module is never stripped
134}
135
136void ObjectFileJIT::CreateSections(SectionList &unified_section_list) {
137  if (!m_sections_up) {
138    m_sections_up.reset(new SectionList());
139    ObjectFileJITDelegateSP delegate_sp(m_delegate_wp.lock());
140    if (delegate_sp) {
141      delegate_sp->PopulateSectionList(this, *m_sections_up);
142      unified_section_list = *m_sections_up;
143    }
144  }
145}
146
147void ObjectFileJIT::Dump(Stream *s) {
148  ModuleSP module_sp(GetModule());
149  if (module_sp) {
150    std::lock_guard<std::recursive_mutex> guard(module_sp->GetMutex());
151    s->Printf("%p: ", static_cast<void *>(this));
152    s->Indent();
153    s->PutCString("ObjectFileJIT");
154
155    if (ArchSpec arch = GetArchitecture())
156      *s << ", arch = " << arch.GetArchitectureName();
157
158    s->EOL();
159
160    SectionList *sections = GetSectionList();
161    if (sections)
162      sections->Dump(s, nullptr, true, UINT32_MAX);
163
164    if (m_symtab_up)
165      m_symtab_up->Dump(s, nullptr, eSortOrderNone);
166  }
167}
168
169UUID ObjectFileJIT::GetUUID() {
170  // TODO: maybe get from delegate, not needed for first pass
171  return UUID();
172}
173
174uint32_t ObjectFileJIT::GetDependentModules(FileSpecList &files) {
175  // JIT modules don't have dependencies, but they could
176  // if external functions are called and we know where they are
177  files.Clear();
178  return 0;
179}
180
181lldb_private::Address ObjectFileJIT::GetEntryPointAddress() {
182  return Address();
183}
184
185lldb_private::Address ObjectFileJIT::GetBaseAddress() { return Address(); }
186
187ObjectFile::Type ObjectFileJIT::CalculateType() { return eTypeJIT; }
188
189ObjectFile::Strata ObjectFileJIT::CalculateStrata() { return eStrataJIT; }
190
191ArchSpec ObjectFileJIT::GetArchitecture() {
192  if (ObjectFileJITDelegateSP delegate_sp = m_delegate_wp.lock())
193    return delegate_sp->GetArchitecture();
194  return ArchSpec();
195}
196
197// PluginInterface protocol
198lldb_private::ConstString ObjectFileJIT::GetPluginName() {
199  return GetPluginNameStatic();
200}
201
202uint32_t ObjectFileJIT::GetPluginVersion() { return 1; }
203
204bool ObjectFileJIT::SetLoadAddress(Target &target, lldb::addr_t value,
205                                   bool value_is_offset) {
206  size_t num_loaded_sections = 0;
207  SectionList *section_list = GetSectionList();
208  if (section_list) {
209    const size_t num_sections = section_list->GetSize();
210    // "value" is an offset to apply to each top level segment
211    for (size_t sect_idx = 0; sect_idx < num_sections; ++sect_idx) {
212      // Iterate through the object file sections to find all of the sections
213      // that size on disk (to avoid __PAGEZERO) and load them
214      SectionSP section_sp(section_list->GetSectionAtIndex(sect_idx));
215      if (section_sp && section_sp->GetFileSize() > 0 &&
216          !section_sp->IsThreadSpecific()) {
217        if (target.GetSectionLoadList().SetSectionLoadAddress(
218                section_sp, section_sp->GetFileAddress() + value))
219          ++num_loaded_sections;
220      }
221    }
222  }
223  return num_loaded_sections > 0;
224}
225
226size_t ObjectFileJIT::ReadSectionData(lldb_private::Section *section,
227                                      lldb::offset_t section_offset, void *dst,
228                                      size_t dst_len) {
229  lldb::offset_t file_size = section->GetFileSize();
230  if (section_offset < file_size) {
231    size_t src_len = file_size - section_offset;
232    if (src_len > dst_len)
233      src_len = dst_len;
234    const uint8_t *src =
235        ((uint8_t *)(uintptr_t)section->GetFileOffset()) + section_offset;
236
237    memcpy(dst, src, src_len);
238    return src_len;
239  }
240  return 0;
241}
242
243size_t ObjectFileJIT::ReadSectionData(
244    lldb_private::Section *section,
245    lldb_private::DataExtractor &section_data) {
246  if (section->GetFileSize()) {
247    const void *src = (void *)(uintptr_t)section->GetFileOffset();
248
249    DataBufferSP data_sp =
250        std::make_shared<DataBufferHeap>(src, section->GetFileSize());
251    section_data.SetData(data_sp, 0, data_sp->GetByteSize());
252    section_data.SetByteOrder(GetByteOrder());
253    section_data.SetAddressByteSize(GetAddressByteSize());
254    return section_data.GetByteSize();
255  }
256  section_data.Clear();
257  return 0;
258}
259