[Lldb-commits] [lldb] [lldb][ElfCore] Improve main executable detection in core files (PR #157170)

via lldb-commits lldb-commits at lists.llvm.org
Wed Sep 10 14:49:59 PDT 2025


https://github.com/GeorgeHuyubo updated https://github.com/llvm/llvm-project/pull/157170

>From f778f2440450da985aff12e4e7b992a83c0f963c Mon Sep 17 00:00:00 2001
From: George Hu <hyubo at meta.com>
Date: Fri, 5 Sep 2025 13:23:48 -0700
Subject: [PATCH] [lldb][ElfCore] Improve main executable detection in core
 files

---
 .../Process/elf-core/ProcessElfCore.cpp       |   45 +-
 .../elf-core/ProcessElfCore.cpp.backup        | 1131 +++++++++++++++++
 .../Plugins/Process/elf-core/ProcessElfCore.h |   10 +
 3 files changed, 1173 insertions(+), 13 deletions(-)
 create mode 100644 lldb/source/Plugins/Process/elf-core/ProcessElfCore.cpp.backup

diff --git a/lldb/source/Plugins/Process/elf-core/ProcessElfCore.cpp b/lldb/source/Plugins/Process/elf-core/ProcessElfCore.cpp
index 88eeddf178788..008320cfc59bc 100644
--- a/lldb/source/Plugins/Process/elf-core/ProcessElfCore.cpp
+++ b/lldb/source/Plugins/Process/elf-core/ProcessElfCore.cpp
@@ -99,7 +99,7 @@ bool ProcessElfCore::CanDebug(lldb::TargetSP target_sp,
 ProcessElfCore::ProcessElfCore(lldb::TargetSP target_sp,
                                lldb::ListenerSP listener_sp,
                                const FileSpec &core_file)
-    : PostMortemProcess(target_sp, listener_sp, core_file) {}
+    : PostMortemProcess(target_sp, listener_sp, core_file), m_uuids() {}
 
 // Destructor
 ProcessElfCore::~ProcessElfCore() {
@@ -257,12 +257,12 @@ Status ProcessElfCore::DoLoadCore() {
   // the main executable using data we found in the core file notes.
   lldb::ModuleSP exe_module_sp = GetTarget().GetExecutableModule();
   if (!exe_module_sp) {
-    // The first entry in the NT_FILE might be our executable
     if (!m_nt_file_entries.empty()) {
+      llvm::StringRef executable_path = GetMainExecutablePath();
       ModuleSpec exe_module_spec;
       exe_module_spec.GetArchitecture() = arch;
-      exe_module_spec.GetUUID() = m_nt_file_entries[0].uuid;
-      exe_module_spec.GetFileSpec().SetFile(m_nt_file_entries[0].path,
+      exe_module_spec.GetUUID() = FindModuleUUID(executable_path);
+      exe_module_spec.GetFileSpec().SetFile(executable_path,
                                             FileSpec::Style::native);
       if (exe_module_spec.GetFileSpec()) {
         exe_module_sp =
@@ -277,21 +277,39 @@ Status ProcessElfCore::DoLoadCore() {
 
 void ProcessElfCore::UpdateBuildIdForNTFileEntries() {
   Log *log = GetLog(LLDBLog::Process);
+  m_uuids.clear();
   for (NT_FILE_Entry &entry : m_nt_file_entries) {
     entry.uuid = FindBuidIdInCoreMemory(entry.start);
-    if (log && entry.uuid.IsValid())
-      LLDB_LOGF(log, "%s found UUID @ %16.16" PRIx64 ": %s \"%s\"",
-                __FUNCTION__, entry.start, entry.uuid.GetAsString().c_str(),
-                entry.path.c_str());
+    if (entry.uuid.IsValid()) {
+      // Assert that either the path is not in the map or the UUID matches
+      assert(m_uuids.count(entry.path) == 0 ||
+             m_uuids[entry.path] == entry.uuid);
+      m_uuids[entry.path] = entry.uuid;
+      if (log)
+        LLDB_LOGF(log, "%s found UUID @ %16.16" PRIx64 ": %s \"%s\"",
+                  __FUNCTION__, entry.start, entry.uuid.GetAsString().c_str(),
+                  entry.path.c_str());
+    }
   }
 }
 
+llvm::StringRef ProcessElfCore::GetMainExecutablePath() {
+  if (m_nt_file_entries.empty())
+    return "";
+
+  // The first entry in the NT_FILE might be our executable
+  llvm::StringRef executable_path = m_nt_file_entries[0].path;
+  // Prefer the NT_FILE entry matching m_executable_name as main executable.
+  for (const NT_FILE_Entry &file_entry : m_nt_file_entries)
+    if (llvm::StringRef(file_entry.path).ends_with("/" + m_executable_name)) {
+      executable_path = file_entry.path;
+      break;
+    }
+  return executable_path;
+}
+
 UUID ProcessElfCore::FindModuleUUID(const llvm::StringRef path) {
-  // Returns the gnu uuid from matched NT_FILE entry
-  for (NT_FILE_Entry &entry : m_nt_file_entries)
-    if (path == entry.path && entry.uuid.IsValid())
-      return entry.uuid;
-  return UUID();
+  return m_uuids[std::string(path)];
 }
 
 lldb_private::DynamicLoader *ProcessElfCore::GetDynamicLoader() {
@@ -935,6 +953,7 @@ llvm::Error ProcessElfCore::parseLinuxNotes(llvm::ArrayRef<CoreNote> notes) {
         return status.ToError();
       thread_data.name.assign (prpsinfo.pr_fname, strnlen (prpsinfo.pr_fname, sizeof (prpsinfo.pr_fname)));
       SetID(prpsinfo.pr_pid);
+      m_executable_name = prpsinfo.pr_fname;
       break;
     }
     case ELF::NT_SIGINFO: {
diff --git a/lldb/source/Plugins/Process/elf-core/ProcessElfCore.cpp.backup b/lldb/source/Plugins/Process/elf-core/ProcessElfCore.cpp.backup
new file mode 100644
index 0000000000000..e88daebebfa7e
--- /dev/null
+++ b/lldb/source/Plugins/Process/elf-core/ProcessElfCore.cpp.backup
@@ -0,0 +1,1131 @@
+//===-- ProcessElfCore.cpp ------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include <cstdlib>
+
+#include <memory>
+#include <mutex>
+
+#include "lldb/Core/Module.h"
+#include "lldb/Core/ModuleSpec.h"
+#include "lldb/Core/PluginManager.h"
+#include "lldb/Core/Section.h"
+#include "lldb/Target/ABI.h"
+#include "lldb/Target/DynamicLoader.h"
+#include "lldb/Target/MemoryRegionInfo.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Target/UnixSignals.h"
+#include "lldb/Utility/DataBufferHeap.h"
+#include "lldb/Utility/LLDBLog.h"
+#include "lldb/Utility/Log.h"
+#include "lldb/Utility/State.h"
+
+#include "llvm/BinaryFormat/ELF.h"
+#include "llvm/Support/Threading.h"
+
+#include "Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.h"
+#include "Plugins/ObjectFile/ELF/ObjectFileELF.h"
+#include "Plugins/Process/elf-core/RegisterUtilities.h"
+#include "ProcessElfCore.h"
+#include "ThreadElfCore.h"
+
+using namespace lldb_private;
+namespace ELF = llvm::ELF;
+
+LLDB_PLUGIN_DEFINE(ProcessElfCore)
+
+llvm::StringRef ProcessElfCore::GetPluginDescriptionStatic() {
+  return "ELF core dump plug-in.";
+}
+
+void ProcessElfCore::Terminate() {
+  PluginManager::UnregisterPlugin(ProcessElfCore::CreateInstance);
+}
+
+lldb::ProcessSP ProcessElfCore::CreateInstance(lldb::TargetSP target_sp,
+                                               lldb::ListenerSP listener_sp,
+                                               const FileSpec *crash_file,
+                                               bool can_connect) {
+  lldb::ProcessSP process_sp;
+  if (crash_file && !can_connect) {
+    // Read enough data for an ELF32 header or ELF64 header Note: Here we care
+    // about e_type field only, so it is safe to ignore possible presence of
+    // the header extension.
+    const size_t header_size = sizeof(llvm::ELF::Elf64_Ehdr);
+
+    auto data_sp = FileSystem::Instance().CreateDataBuffer(
+        crash_file->GetPath(), header_size, 0);
+    if (data_sp && data_sp->GetByteSize() == header_size &&
+        elf::ELFHeader::MagicBytesMatch(data_sp->GetBytes())) {
+      elf::ELFHeader elf_header;
+      DataExtractor data(data_sp, lldb::eByteOrderLittle, 4);
+      lldb::offset_t data_offset = 0;
+      if (elf_header.Parse(data, &data_offset)) {
+        // Check whether we're dealing with a raw FreeBSD "full memory dump"
+        // ELF vmcore that needs to be handled via FreeBSDKernel plugin instead.
+        if (elf_header.e_ident[7] == 0xFF && elf_header.e_version == 0)
+          return process_sp;
+        if (elf_header.e_type == llvm::ELF::ET_CORE)
+          process_sp = std::make_shared<ProcessElfCore>(target_sp, listener_sp,
+                                                        *crash_file);
+      }
+    }
+  }
+  return process_sp;
+}
+
+bool ProcessElfCore::CanDebug(lldb::TargetSP target_sp,
+                              bool plugin_specified_by_name) {
+  // For now we are just making sure the file exists for a given module
+  if (!m_core_module_sp && FileSystem::Instance().Exists(m_core_file)) {
+    ModuleSpec core_module_spec(m_core_file, target_sp->GetArchitecture());
+    Status error(ModuleList::GetSharedModule(core_module_spec, m_core_module_sp,
+                                             nullptr, nullptr, nullptr));
+    if (m_core_module_sp) {
+      ObjectFile *core_objfile = m_core_module_sp->GetObjectFile();
+      if (core_objfile && core_objfile->GetType() == ObjectFile::eTypeCoreFile)
+        return true;
+    }
+  }
+  return false;
+}
+
+// ProcessElfCore constructor
+ProcessElfCore::ProcessElfCore(lldb::TargetSP target_sp,
+                               lldb::ListenerSP listener_sp,
+                               const FileSpec &core_file)
+    : PostMortemProcess(target_sp, listener_sp, core_file) {}
+
+// Destructor
+ProcessElfCore::~ProcessElfCore() {
+  Clear();
+  // We need to call finalize on the process before destroying ourselves to
+  // make sure all of the broadcaster cleanup goes as planned. If we destruct
+  // this class, then Process::~Process() might have problems trying to fully
+  // destroy the broadcaster.
+  Finalize(true /* destructing */);
+}
+
+lldb::addr_t ProcessElfCore::AddAddressRangeFromLoadSegment(
+    const elf::ELFProgramHeader &header) {
+  const lldb::addr_t addr = header.p_vaddr;
+  FileRange file_range(header.p_offset, header.p_filesz);
+  VMRangeToFileOffset::Entry range_entry(addr, header.p_memsz, file_range);
+
+  // Only add to m_core_aranges if the file size is non zero. Some core files
+  // have PT_LOAD segments for all address ranges, but set f_filesz to zero for
+  // the .text sections since they can be retrieved from the object files.
+  if (header.p_filesz > 0) {
+    VMRangeToFileOffset::Entry *last_entry = m_core_aranges.Back();
+    if (last_entry && last_entry->GetRangeEnd() == range_entry.GetRangeBase() &&
+        last_entry->data.GetRangeEnd() == range_entry.data.GetRangeBase() &&
+        last_entry->GetByteSize() == last_entry->data.GetByteSize()) {
+      last_entry->SetRangeEnd(range_entry.GetRangeEnd());
+      last_entry->data.SetRangeEnd(range_entry.data.GetRangeEnd());
+    } else {
+      m_core_aranges.Append(range_entry);
+    }
+  }
+  // Keep a separate map of permissions that isn't coalesced so all ranges
+  // are maintained.
+  const uint32_t permissions =
+      ((header.p_flags & llvm::ELF::PF_R) ? lldb::ePermissionsReadable : 0u) |
+      ((header.p_flags & llvm::ELF::PF_W) ? lldb::ePermissionsWritable : 0u) |
+      ((header.p_flags & llvm::ELF::PF_X) ? lldb::ePermissionsExecutable : 0u);
+
+  m_core_range_infos.Append(
+      VMRangeToPermissions::Entry(addr, header.p_memsz, permissions));
+
+  return addr;
+}
+
+lldb::addr_t ProcessElfCore::AddAddressRangeFromMemoryTagSegment(
+    const elf::ELFProgramHeader &header) {
+  // If lldb understood multiple kinds of tag segments we would record the type
+  // of the segment here also. As long as there is only 1 type lldb looks for,
+  // there is no need.
+  FileRange file_range(header.p_offset, header.p_filesz);
+  m_core_tag_ranges.Append(
+      VMRangeToFileOffset::Entry(header.p_vaddr, header.p_memsz, file_range));
+
+  return header.p_vaddr;
+}
+
+// Process Control
+Status ProcessElfCore::DoLoadCore() {
+  Status error;
+  if (!m_core_module_sp) {
+    error = Status::FromErrorString("invalid core module");
+    return error;
+  }
+
+  ObjectFileELF *core = (ObjectFileELF *)(m_core_module_sp->GetObjectFile());
+  if (core == nullptr) {
+    error = Status::FromErrorString("invalid core object file");
+    return error;
+  }
+
+  llvm::ArrayRef<elf::ELFProgramHeader> segments = core->ProgramHeaders();
+  if (segments.size() == 0) {
+    error = Status::FromErrorString("core file has no segments");
+    return error;
+  }
+
+  // Even if the architecture is set in the target, we need to override it to
+  // match the core file which is always single arch.
+  ArchSpec arch(m_core_module_sp->GetArchitecture());
+
+  ArchSpec target_arch = GetTarget().GetArchitecture();
+  ArchSpec core_arch(m_core_module_sp->GetArchitecture());
+  target_arch.MergeFrom(core_arch);
+  GetTarget().SetArchitecture(target_arch, /*set_platform*/ true);
+
+  SetUnixSignals(UnixSignals::Create(GetArchitecture()));
+
+  SetCanJIT(false);
+
+  m_thread_data_valid = true;
+
+  bool ranges_are_sorted = true;
+  lldb::addr_t vm_addr = 0;
+  lldb::addr_t tag_addr = 0;
+  /// Walk through segments and Thread and Address Map information.
+  /// PT_NOTE - Contains Thread and Register information
+  /// PT_LOAD - Contains a contiguous range of Process Address Space
+  /// PT_AARCH64_MEMTAG_MTE - Contains AArch64 MTE memory tags for a range of
+  ///                         Process Address Space.
+  for (const elf::ELFProgramHeader &H : segments) {
+    DataExtractor data = core->GetSegmentData(H);
+
+    // Parse thread contexts and auxv structure
+    if (H.p_type == llvm::ELF::PT_NOTE) {
+      if (llvm::Error error = ParseThreadContextsFromNoteSegment(H, data))
+        return Status::FromError(std::move(error));
+    }
+    // PT_LOAD segments contains address map
+    if (H.p_type == llvm::ELF::PT_LOAD) {
+      lldb::addr_t last_addr = AddAddressRangeFromLoadSegment(H);
+      if (vm_addr > last_addr)
+        ranges_are_sorted = false;
+      vm_addr = last_addr;
+    } else if (H.p_type == llvm::ELF::PT_AARCH64_MEMTAG_MTE) {
+      lldb::addr_t last_addr = AddAddressRangeFromMemoryTagSegment(H);
+      if (tag_addr > last_addr)
+        ranges_are_sorted = false;
+      tag_addr = last_addr;
+    }
+  }
+
+  if (!ranges_are_sorted) {
+    m_core_aranges.Sort();
+    m_core_range_infos.Sort();
+    m_core_tag_ranges.Sort();
+  }
+
+  // Ensure we found at least one thread that was stopped on a signal.
+  bool siginfo_signal_found = false;
+  bool prstatus_signal_found = false;
+  // Check we found a signal in a SIGINFO note.
+  for (const auto &thread_data : m_thread_data) {
+    if (!thread_data.siginfo_bytes.empty() || thread_data.signo != 0)
+      siginfo_signal_found = true;
+    if (thread_data.prstatus_sig != 0)
+      prstatus_signal_found = true;
+  }
+  if (!siginfo_signal_found) {
+    // If we don't have signal from SIGINFO use the signal from each threads
+    // PRSTATUS note.
+    if (prstatus_signal_found) {
+      for (auto &thread_data : m_thread_data)
+        thread_data.signo = thread_data.prstatus_sig;
+    } else if (m_thread_data.size() > 0) {
+      // If all else fails force the first thread to be SIGSTOP
+      m_thread_data.begin()->signo =
+          GetUnixSignals()->GetSignalNumberFromName("SIGSTOP");
+    }
+  }
+
+  // Try to find gnu build id before we load the executable.
+  UpdateBuildIdForNTFileEntries();
+
+  // Core files are useless without the main executable. See if we can locate
+  // the main executable using data we found in the core file notes.
+  lldb::ModuleSP exe_module_sp = GetTarget().GetExecutableModule();
+  if (!exe_module_sp) {
+    if (!m_nt_file_entries.empty()) {
+      // The first entry in the NT_FILE might be our executable
+      llvm::StringRef executable_path = m_nt_file_entries[0].path;
+      // Prefer the NT_FILE entry matching m_executable_name as main executable.
+      for (const NT_FILE_Entry &file_entry : m_nt_file_entries)
+        if (llvm::StringRef(file_entry.path)
+                .ends_with("/" + m_executable_name)) {
+          executable_path = file_entry.path;
+          break;
+        }
+
+      ModuleSpec exe_module_spec;
+      exe_module_spec.GetArchitecture() = arch;
+      exe_module_spec.GetUUID() = FindModuleUUID(executable_path);
+      exe_module_spec.GetFileSpec().SetFile(executable_path,
+                                            FileSpec::Style::native);
+      if (exe_module_spec.GetFileSpec()) {
+        exe_module_sp =
+            GetTarget().GetOrCreateModule(exe_module_spec, true /* notify */);
+        if (exe_module_sp)
+          GetTarget().SetExecutableModule(exe_module_sp, eLoadDependentsNo);
+      }
+    }
+  }
+  return error;
+}
+
+void ProcessElfCore::UpdateBuildIdForNTFileEntries() {
+  Log *log = GetLog(LLDBLog::Process);
+  for (NT_FILE_Entry &entry : m_nt_file_entries) {
+    entry.uuid = FindBuidIdInCoreMemory(entry.start);
+    if (log && entry.uuid.IsValid())
+      LLDB_LOGF(log, "%s found UUID @ %16.16" PRIx64 ": %s \"%s\"",
+                __FUNCTION__, entry.start, entry.uuid.GetAsString().c_str(),
+                entry.path.c_str());
+  }
+}
+
+UUID ProcessElfCore::FindModuleUUID(const llvm::StringRef path) {
+  // Returns the gnu uuid from matched NT_FILE entry
+  for (NT_FILE_Entry &entry : m_nt_file_entries)
+    if (path == entry.path && entry.uuid.IsValid())
+      return entry.uuid;
+  return UUID();
+}
+
+lldb_private::DynamicLoader *ProcessElfCore::GetDynamicLoader() {
+  if (m_dyld_up.get() == nullptr)
+    m_dyld_up.reset(DynamicLoader::FindPlugin(
+        this, DynamicLoaderPOSIXDYLD::GetPluginNameStatic()));
+  return m_dyld_up.get();
+}
+
+bool ProcessElfCore::DoUpdateThreadList(ThreadList &old_thread_list,
+                                        ThreadList &new_thread_list) {
+  const uint32_t num_threads = GetNumThreadContexts();
+  if (!m_thread_data_valid)
+    return false;
+
+  for (lldb::tid_t tid = 0; tid < num_threads; ++tid) {
+    const ThreadData &td = m_thread_data[tid];
+    lldb::ThreadSP thread_sp(new ThreadElfCore(*this, td));
+    new_thread_list.AddThread(thread_sp);
+  }
+  return new_thread_list.GetSize(false) > 0;
+}
+
+void ProcessElfCore::RefreshStateAfterStop() {}
+
+Status ProcessElfCore::DoDestroy() { return Status(); }
+
+// Process Queries
+
+bool ProcessElfCore::IsAlive() { return true; }
+
+// Process Memory
+size_t ProcessElfCore::ReadMemory(lldb::addr_t addr, void *buf, size_t size,
+                                  Status &error) {
+  if (lldb::ABISP abi_sp = GetABI())
+    addr = abi_sp->FixAnyAddress(addr);
+
+  // Don't allow the caching that lldb_private::Process::ReadMemory does since
+  // in core files we have it all cached our our core file anyway.
+  return DoReadMemory(addr, buf, size, error);
+}
+
+Status ProcessElfCore::DoGetMemoryRegionInfo(lldb::addr_t load_addr,
+                                             MemoryRegionInfo &region_info) {
+  region_info.Clear();
+  const VMRangeToPermissions::Entry *permission_entry =
+      m_core_range_infos.FindEntryThatContainsOrFollows(load_addr);
+  if (permission_entry) {
+    if (permission_entry->Contains(load_addr)) {
+      region_info.GetRange().SetRangeBase(permission_entry->GetRangeBase());
+      region_info.GetRange().SetRangeEnd(permission_entry->GetRangeEnd());
+      const Flags permissions(permission_entry->data);
+      region_info.SetReadable(permissions.Test(lldb::ePermissionsReadable)
+                                  ? MemoryRegionInfo::eYes
+                                  : MemoryRegionInfo::eNo);
+      region_info.SetWritable(permissions.Test(lldb::ePermissionsWritable)
+                                  ? MemoryRegionInfo::eYes
+                                  : MemoryRegionInfo::eNo);
+      region_info.SetExecutable(permissions.Test(lldb::ePermissionsExecutable)
+                                    ? MemoryRegionInfo::eYes
+                                    : MemoryRegionInfo::eNo);
+      region_info.SetMapped(MemoryRegionInfo::eYes);
+
+      // A region is memory tagged if there is a memory tag segment that covers
+      // the exact same range.
+      region_info.SetMemoryTagged(MemoryRegionInfo::eNo);
+      const VMRangeToFileOffset::Entry *tag_entry =
+          m_core_tag_ranges.FindEntryStartsAt(permission_entry->GetRangeBase());
+      if (tag_entry &&
+          tag_entry->GetRangeEnd() == permission_entry->GetRangeEnd())
+        region_info.SetMemoryTagged(MemoryRegionInfo::eYes);
+    } else if (load_addr < permission_entry->GetRangeBase()) {
+      region_info.GetRange().SetRangeBase(load_addr);
+      region_info.GetRange().SetRangeEnd(permission_entry->GetRangeBase());
+      region_info.SetReadable(MemoryRegionInfo::eNo);
+      region_info.SetWritable(MemoryRegionInfo::eNo);
+      region_info.SetExecutable(MemoryRegionInfo::eNo);
+      region_info.SetMapped(MemoryRegionInfo::eNo);
+      region_info.SetMemoryTagged(MemoryRegionInfo::eNo);
+    }
+    return Status();
+  }
+
+  region_info.GetRange().SetRangeBase(load_addr);
+  region_info.GetRange().SetRangeEnd(LLDB_INVALID_ADDRESS);
+  region_info.SetReadable(MemoryRegionInfo::eNo);
+  region_info.SetWritable(MemoryRegionInfo::eNo);
+  region_info.SetExecutable(MemoryRegionInfo::eNo);
+  region_info.SetMapped(MemoryRegionInfo::eNo);
+  region_info.SetMemoryTagged(MemoryRegionInfo::eNo);
+  return Status();
+}
+
+size_t ProcessElfCore::DoReadMemory(lldb::addr_t addr, void *buf, size_t size,
+                                    Status &error) {
+  ObjectFile *core_objfile = m_core_module_sp->GetObjectFile();
+
+  if (core_objfile == nullptr)
+    return 0;
+
+  // Get the address range
+  const VMRangeToFileOffset::Entry *address_range =
+      m_core_aranges.FindEntryThatContains(addr);
+  if (address_range == nullptr || address_range->GetRangeEnd() < addr) {
+    error = Status::FromErrorStringWithFormat(
+        "core file does not contain 0x%" PRIx64, addr);
+    return 0;
+  }
+
+  // Convert the address into core file offset
+  const lldb::addr_t offset = addr - address_range->GetRangeBase();
+  const lldb::addr_t file_start = address_range->data.GetRangeBase();
+  const lldb::addr_t file_end = address_range->data.GetRangeEnd();
+  size_t bytes_to_read = size; // Number of bytes to read from the core file
+  size_t bytes_copied = 0;   // Number of bytes actually read from the core file
+  lldb::addr_t bytes_left =
+      0; // Number of bytes available in the core file from the given address
+
+  // Don't proceed if core file doesn't contain the actual data for this
+  // address range.
+  if (file_start == file_end)
+    return 0;
+
+  // Figure out how many on-disk bytes remain in this segment starting at the
+  // given offset
+  if (file_end > file_start + offset)
+    bytes_left = file_end - (file_start + offset);
+
+  if (bytes_to_read > bytes_left)
+    bytes_to_read = bytes_left;
+
+  // If there is data available on the core file read it
+  if (bytes_to_read)
+    bytes_copied =
+        core_objfile->CopyData(offset + file_start, bytes_to_read, buf);
+
+  return bytes_copied;
+}
+
+llvm::Expected<std::vector<lldb::addr_t>>
+ProcessElfCore::ReadMemoryTags(lldb::addr_t addr, size_t len) {
+  ObjectFile *core_objfile = m_core_module_sp->GetObjectFile();
+  if (core_objfile == nullptr)
+    return llvm::createStringError(llvm::inconvertibleErrorCode(),
+                                   "No core object file.");
+
+  llvm::Expected<const MemoryTagManager *> tag_manager_or_err =
+      GetMemoryTagManager();
+  if (!tag_manager_or_err)
+    return tag_manager_or_err.takeError();
+
+  // LLDB only supports AArch64 MTE tag segments so we do not need to worry
+  // about the segment type here. If you got here then you must have a tag
+  // manager (meaning you are debugging AArch64) and all the segments in this
+  // list will have had type PT_AARCH64_MEMTAG_MTE.
+  const VMRangeToFileOffset::Entry *tag_entry =
+      m_core_tag_ranges.FindEntryThatContains(addr);
+  // If we don't have a tag segment or the range asked for extends outside the
+  // segment.
+  if (!tag_entry || (addr + len) >= tag_entry->GetRangeEnd())
+    return llvm::createStringError(llvm::inconvertibleErrorCode(),
+                                   "No tag segment that covers this range.");
+
+  const MemoryTagManager *tag_manager = *tag_manager_or_err;
+  return tag_manager->UnpackTagsFromCoreFileSegment(
+      [core_objfile](lldb::offset_t offset, size_t length, void *dst) {
+        return core_objfile->CopyData(offset, length, dst);
+      },
+      tag_entry->GetRangeBase(), tag_entry->data.GetRangeBase(), addr, len);
+}
+
+void ProcessElfCore::Clear() {
+  m_thread_list.Clear();
+
+  SetUnixSignals(std::make_shared<UnixSignals>());
+}
+
+void ProcessElfCore::Initialize() {
+  static llvm::once_flag g_once_flag;
+
+  llvm::call_once(g_once_flag, []() {
+    PluginManager::RegisterPlugin(GetPluginNameStatic(),
+                                  GetPluginDescriptionStatic(), CreateInstance);
+  });
+}
+
+lldb::addr_t ProcessElfCore::GetImageInfoAddress() {
+  ObjectFile *obj_file = GetTarget().GetExecutableModule()->GetObjectFile();
+  Address addr = obj_file->GetImageInfoAddress(&GetTarget());
+
+  if (addr.IsValid())
+    return addr.GetLoadAddress(&GetTarget());
+  return LLDB_INVALID_ADDRESS;
+}
+
+// Parse a FreeBSD NT_PRSTATUS note - see FreeBSD sys/procfs.h for details.
+static void ParseFreeBSDPrStatus(ThreadData &thread_data,
+                                 const DataExtractor &data,
+                                 bool lp64) {
+  lldb::offset_t offset = 0;
+  int pr_version = data.GetU32(&offset);
+
+  Log *log = GetLog(LLDBLog::Process);
+  if (log) {
+    if (pr_version > 1)
+      LLDB_LOGF(log, "FreeBSD PRSTATUS unexpected version %d", pr_version);
+  }
+
+  // Skip padding, pr_statussz, pr_gregsetsz, pr_fpregsetsz, pr_osreldate
+  if (lp64)
+    offset += 32;
+  else
+    offset += 16;
+
+  thread_data.signo = data.GetU32(&offset); // pr_cursig
+  thread_data.tid = data.GetU32(&offset);   // pr_pid
+  if (lp64)
+    offset += 4;
+
+  size_t len = data.GetByteSize() - offset;
+  thread_data.gpregset = DataExtractor(data, offset, len);
+}
+
+// Parse a FreeBSD NT_PRPSINFO note - see FreeBSD sys/procfs.h for details.
+static void ParseFreeBSDPrPsInfo(ProcessElfCore &process,
+                                 const DataExtractor &data,
+                                 bool lp64) {
+  lldb::offset_t offset = 0;
+  int pr_version = data.GetU32(&offset);
+
+  Log *log = GetLog(LLDBLog::Process);
+  if (log) {
+    if (pr_version > 1)
+      LLDB_LOGF(log, "FreeBSD PRPSINFO unexpected version %d", pr_version);
+  }
+
+  // Skip pr_psinfosz, pr_fname, pr_psargs
+  offset += 108;
+  if (lp64)
+    offset += 4;
+
+  process.SetID(data.GetU32(&offset)); // pr_pid
+}
+
+static llvm::Error ParseNetBSDProcInfo(const DataExtractor &data,
+                                       uint32_t &cpi_nlwps,
+                                       uint32_t &cpi_signo,
+                                       uint32_t &cpi_siglwp,
+                                       uint32_t &cpi_pid) {
+  lldb::offset_t offset = 0;
+
+  uint32_t version = data.GetU32(&offset);
+  if (version != 1)
+    return llvm::make_error<llvm::StringError>(
+        "Error parsing NetBSD core(5) notes: Unsupported procinfo version",
+        llvm::inconvertibleErrorCode());
+
+  uint32_t cpisize = data.GetU32(&offset);
+  if (cpisize != NETBSD::NT_PROCINFO_SIZE)
+    return llvm::make_error<llvm::StringError>(
+        "Error parsing NetBSD core(5) notes: Unsupported procinfo size",
+        llvm::inconvertibleErrorCode());
+
+  cpi_signo = data.GetU32(&offset); /* killing signal */
+
+  offset += NETBSD::NT_PROCINFO_CPI_SIGCODE_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_SIGPEND_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_SIGMASK_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_SIGIGNORE_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_SIGCATCH_SIZE;
+  cpi_pid = data.GetU32(&offset);
+  offset += NETBSD::NT_PROCINFO_CPI_PPID_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_PGRP_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_SID_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_RUID_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_EUID_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_SVUID_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_RGID_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_EGID_SIZE;
+  offset += NETBSD::NT_PROCINFO_CPI_SVGID_SIZE;
+  cpi_nlwps = data.GetU32(&offset); /* number of LWPs */
+
+  offset += NETBSD::NT_PROCINFO_CPI_NAME_SIZE;
+  cpi_siglwp = data.GetU32(&offset); /* LWP target of killing signal */
+
+  return llvm::Error::success();
+}
+
+static void ParseOpenBSDProcInfo(ThreadData &thread_data,
+                                 const DataExtractor &data) {
+  lldb::offset_t offset = 0;
+
+  int version = data.GetU32(&offset);
+  if (version != 1)
+    return;
+
+  offset += 4;
+  thread_data.signo = data.GetU32(&offset);
+}
+
+llvm::Expected<std::vector<CoreNote>>
+ProcessElfCore::parseSegment(const DataExtractor &segment) {
+  lldb::offset_t offset = 0;
+  std::vector<CoreNote> result;
+
+  while (offset < segment.GetByteSize()) {
+    ELFNote note = ELFNote();
+    if (!note.Parse(segment, &offset))
+      return llvm::make_error<llvm::StringError>(
+          "Unable to parse note segment", llvm::inconvertibleErrorCode());
+
+    size_t note_start = offset;
+    size_t note_size = llvm::alignTo(note.n_descsz, 4);
+
+    result.push_back({note, DataExtractor(segment, note_start, note_size)});
+    offset += note_size;
+  }
+
+  return std::move(result);
+}
+
+llvm::Error ProcessElfCore::parseFreeBSDNotes(llvm::ArrayRef<CoreNote> notes) {
+  ArchSpec arch = GetArchitecture();
+  bool lp64 = (arch.GetMachine() == llvm::Triple::aarch64 ||
+               arch.GetMachine() == llvm::Triple::mips64 ||
+               arch.GetMachine() == llvm::Triple::ppc64 ||
+               arch.GetMachine() == llvm::Triple::x86_64);
+  bool have_prstatus = false;
+  bool have_prpsinfo = false;
+  ThreadData thread_data;
+  for (const auto &note : notes) {
+    if (note.info.n_name != "FreeBSD")
+      continue;
+
+    if ((note.info.n_type == ELF::NT_PRSTATUS && have_prstatus) ||
+        (note.info.n_type == ELF::NT_PRPSINFO && have_prpsinfo)) {
+      assert(thread_data.gpregset.GetByteSize() > 0);
+      // Add the new thread to thread list
+      m_thread_data.push_back(thread_data);
+      thread_data = ThreadData();
+      have_prstatus = false;
+      have_prpsinfo = false;
+    }
+
+    switch (note.info.n_type) {
+    case ELF::NT_PRSTATUS:
+      have_prstatus = true;
+      ParseFreeBSDPrStatus(thread_data, note.data, lp64);
+      break;
+    case ELF::NT_PRPSINFO:
+      have_prpsinfo = true;
+      ParseFreeBSDPrPsInfo(*this, note.data, lp64);
+      break;
+    case ELF::NT_FREEBSD_THRMISC: {
+      lldb::offset_t offset = 0;
+      thread_data.name = note.data.GetCStr(&offset, 20);
+      break;
+    }
+    case ELF::NT_FREEBSD_PROCSTAT_AUXV:
+      // FIXME: FreeBSD sticks an int at the beginning of the note
+      m_auxv = DataExtractor(note.data, 4, note.data.GetByteSize() - 4);
+      break;
+    default:
+      thread_data.notes.push_back(note);
+      break;
+    }
+  }
+  if (!have_prstatus) {
+    return llvm::make_error<llvm::StringError>(
+        "Could not find NT_PRSTATUS note in core file.",
+        llvm::inconvertibleErrorCode());
+  }
+  m_thread_data.push_back(thread_data);
+  return llvm::Error::success();
+}
+
+/// NetBSD specific Thread context from PT_NOTE segment
+///
+/// NetBSD ELF core files use notes to provide information about
+/// the process's state.  The note name is "NetBSD-CORE" for
+/// information that is global to the process, and "NetBSD-CORE at nn",
+/// where "nn" is the lwpid of the LWP that the information belongs
+/// to (such as register state).
+///
+/// NetBSD uses the following note identifiers:
+///
+///      ELF_NOTE_NETBSD_CORE_PROCINFO (value 1)
+///             Note is a "netbsd_elfcore_procinfo" structure.
+///      ELF_NOTE_NETBSD_CORE_AUXV     (value 2; since NetBSD 8.0)
+///             Note is an array of AuxInfo structures.
+///
+/// NetBSD also uses ptrace(2) request numbers (the ones that exist in
+/// machine-dependent space) to identify register info notes.  The
+/// info in such notes is in the same format that ptrace(2) would
+/// export that information.
+///
+/// For more information see /usr/include/sys/exec_elf.h
+///
+llvm::Error ProcessElfCore::parseNetBSDNotes(llvm::ArrayRef<CoreNote> notes) {
+  ThreadData thread_data;
+  bool had_nt_regs = false;
+
+  // To be extracted from struct netbsd_elfcore_procinfo
+  // Used to sanity check of the LWPs of the process
+  uint32_t nlwps = 0;
+  uint32_t signo = 0;  // killing signal
+  uint32_t siglwp = 0; // LWP target of killing signal
+  uint32_t pr_pid = 0;
+
+  for (const auto &note : notes) {
+    llvm::StringRef name = note.info.n_name;
+
+    if (name == "NetBSD-CORE") {
+      if (note.info.n_type == NETBSD::NT_PROCINFO) {
+        llvm::Error error = ParseNetBSDProcInfo(note.data, nlwps, signo,
+                                                siglwp, pr_pid);
+        if (error)
+          return error;
+        SetID(pr_pid);
+      } else if (note.info.n_type == NETBSD::NT_AUXV) {
+        m_auxv = note.data;
+      }
+    } else if (name.consume_front("NetBSD-CORE@")) {
+      lldb::tid_t tid;
+      if (name.getAsInteger(10, tid))
+        return llvm::make_error<llvm::StringError>(
+            "Error parsing NetBSD core(5) notes: Cannot convert LWP ID "
+            "to integer",
+            llvm::inconvertibleErrorCode());
+
+      switch (GetArchitecture().GetMachine()) {
+      case llvm::Triple::aarch64: {
+        // Assume order PT_GETREGS, PT_GETFPREGS
+        if (note.info.n_type == NETBSD::AARCH64::NT_REGS) {
+          // If this is the next thread, push the previous one first.
+          if (had_nt_regs) {
+            m_thread_data.push_back(thread_data);
+            thread_data = ThreadData();
+            had_nt_regs = false;
+          }
+
+          thread_data.gpregset = note.data;
+          thread_data.tid = tid;
+          if (thread_data.gpregset.GetByteSize() == 0)
+            return llvm::make_error<llvm::StringError>(
+                "Could not find general purpose registers note in core file.",
+                llvm::inconvertibleErrorCode());
+          had_nt_regs = true;
+        } else if (note.info.n_type == NETBSD::AARCH64::NT_FPREGS) {
+          if (!had_nt_regs || tid != thread_data.tid)
+            return llvm::make_error<llvm::StringError>(
+                "Error parsing NetBSD core(5) notes: Unexpected order "
+                "of NOTEs PT_GETFPREG before PT_GETREG",
+                llvm::inconvertibleErrorCode());
+          thread_data.notes.push_back(note);
+        }
+      } break;
+      case llvm::Triple::x86: {
+        // Assume order PT_GETREGS, PT_GETFPREGS
+        if (note.info.n_type == NETBSD::I386::NT_REGS) {
+          // If this is the next thread, push the previous one first.
+          if (had_nt_regs) {
+            m_thread_data.push_back(thread_data);
+            thread_data = ThreadData();
+            had_nt_regs = false;
+          }
+
+          thread_data.gpregset = note.data;
+          thread_data.tid = tid;
+          if (thread_data.gpregset.GetByteSize() == 0)
+            return llvm::make_error<llvm::StringError>(
+                "Could not find general purpose registers note in core file.",
+                llvm::inconvertibleErrorCode());
+          had_nt_regs = true;
+        } else if (note.info.n_type == NETBSD::I386::NT_FPREGS) {
+          if (!had_nt_regs || tid != thread_data.tid)
+            return llvm::make_error<llvm::StringError>(
+                "Error parsing NetBSD core(5) notes: Unexpected order "
+                "of NOTEs PT_GETFPREG before PT_GETREG",
+                llvm::inconvertibleErrorCode());
+          thread_data.notes.push_back(note);
+        }
+      } break;
+      case llvm::Triple::x86_64: {
+        // Assume order PT_GETREGS, PT_GETFPREGS
+        if (note.info.n_type == NETBSD::AMD64::NT_REGS) {
+          // If this is the next thread, push the previous one first.
+          if (had_nt_regs) {
+            m_thread_data.push_back(thread_data);
+            thread_data = ThreadData();
+            had_nt_regs = false;
+          }
+
+          thread_data.gpregset = note.data;
+          thread_data.tid = tid;
+          if (thread_data.gpregset.GetByteSize() == 0)
+            return llvm::make_error<llvm::StringError>(
+                "Could not find general purpose registers note in core file.",
+                llvm::inconvertibleErrorCode());
+          had_nt_regs = true;
+        } else if (note.info.n_type == NETBSD::AMD64::NT_FPREGS) {
+          if (!had_nt_regs || tid != thread_data.tid)
+            return llvm::make_error<llvm::StringError>(
+                "Error parsing NetBSD core(5) notes: Unexpected order "
+                "of NOTEs PT_GETFPREG before PT_GETREG",
+                llvm::inconvertibleErrorCode());
+          thread_data.notes.push_back(note);
+        }
+      } break;
+      default:
+        break;
+      }
+    }
+  }
+
+  // Push the last thread.
+  if (had_nt_regs)
+    m_thread_data.push_back(thread_data);
+
+  if (m_thread_data.empty())
+    return llvm::make_error<llvm::StringError>(
+        "Error parsing NetBSD core(5) notes: No threads information "
+        "specified in notes",
+        llvm::inconvertibleErrorCode());
+
+  if (m_thread_data.size() != nlwps)
+    return llvm::make_error<llvm::StringError>(
+        "Error parsing NetBSD core(5) notes: Mismatch between the number "
+        "of LWPs in netbsd_elfcore_procinfo and the number of LWPs specified "
+        "by MD notes",
+        llvm::inconvertibleErrorCode());
+
+  // Signal targeted at the whole process.
+  if (siglwp == 0) {
+    for (auto &data : m_thread_data)
+      data.signo = signo;
+  }
+  // Signal destined for a particular LWP.
+  else {
+    bool passed = false;
+
+    for (auto &data : m_thread_data) {
+      if (data.tid == siglwp) {
+        data.signo = signo;
+        passed = true;
+        break;
+      }
+    }
+
+    if (!passed)
+      return llvm::make_error<llvm::StringError>(
+          "Error parsing NetBSD core(5) notes: Signal passed to unknown LWP",
+          llvm::inconvertibleErrorCode());
+  }
+
+  return llvm::Error::success();
+}
+
+llvm::Error ProcessElfCore::parseOpenBSDNotes(llvm::ArrayRef<CoreNote> notes) {
+  ThreadData thread_data = {};
+  for (const auto &note : notes) {
+    // OpenBSD per-thread information is stored in notes named "OpenBSD at nnn" so
+    // match on the initial part of the string.
+    if (!llvm::StringRef(note.info.n_name).starts_with("OpenBSD"))
+      continue;
+
+    switch (note.info.n_type) {
+    case OPENBSD::NT_PROCINFO:
+      ParseOpenBSDProcInfo(thread_data, note.data);
+      break;
+    case OPENBSD::NT_AUXV:
+      m_auxv = note.data;
+      break;
+    case OPENBSD::NT_REGS:
+      thread_data.gpregset = note.data;
+      break;
+    default:
+      thread_data.notes.push_back(note);
+      break;
+    }
+  }
+  if (thread_data.gpregset.GetByteSize() == 0) {
+    return llvm::make_error<llvm::StringError>(
+        "Could not find general purpose registers note in core file.",
+        llvm::inconvertibleErrorCode());
+  }
+  m_thread_data.push_back(thread_data);
+  return llvm::Error::success();
+}
+
+/// A description of a linux process usually contains the following NOTE
+/// entries:
+/// - NT_PRPSINFO - General process information like pid, uid, name, ...
+/// - NT_SIGINFO - Information about the signal that terminated the process
+/// - NT_AUXV - Process auxiliary vector
+/// - NT_FILE - Files mapped into memory
+///
+/// Additionally, for each thread in the process the core file will contain at
+/// least the NT_PRSTATUS note, containing the thread id and general purpose
+/// registers. It may include additional notes for other register sets (floating
+/// point and vector registers, ...). The tricky part here is that some of these
+/// notes have "CORE" in their owner fields, while other set it to "LINUX".
+llvm::Error ProcessElfCore::parseLinuxNotes(llvm::ArrayRef<CoreNote> notes) {
+  const ArchSpec &arch = GetArchitecture();
+  bool have_prstatus = false;
+  bool have_prpsinfo = false;
+  ThreadData thread_data;
+  for (const auto &note : notes) {
+    if (note.info.n_name != "CORE" && note.info.n_name != "LINUX")
+      continue;
+
+    if ((note.info.n_type == ELF::NT_PRSTATUS && have_prstatus) ||
+        (note.info.n_type == ELF::NT_PRPSINFO && have_prpsinfo)) {
+      assert(thread_data.gpregset.GetByteSize() > 0);
+      // Add the new thread to thread list
+      m_thread_data.push_back(thread_data);
+      thread_data = ThreadData();
+      have_prstatus = false;
+      have_prpsinfo = false;
+    }
+
+    switch (note.info.n_type) {
+    case ELF::NT_PRSTATUS: {
+      have_prstatus = true;
+      ELFLinuxPrStatus prstatus;
+      Status status = prstatus.Parse(note.data, arch);
+      if (status.Fail())
+        return status.ToError();
+      thread_data.prstatus_sig = prstatus.pr_cursig;
+      thread_data.tid = prstatus.pr_pid;
+      uint32_t header_size = ELFLinuxPrStatus::GetSize(arch);
+      size_t len = note.data.GetByteSize() - header_size;
+      thread_data.gpregset = DataExtractor(note.data, header_size, len);
+      break;
+    }
+    case ELF::NT_PRPSINFO: {
+      have_prpsinfo = true;
+      ELFLinuxPrPsInfo prpsinfo;
+      Status status = prpsinfo.Parse(note.data, arch);
+      if (status.Fail())
+        return status.ToError();
+      thread_data.name.assign (prpsinfo.pr_fname, strnlen (prpsinfo.pr_fname, sizeof (prpsinfo.pr_fname)));
+      SetID(prpsinfo.pr_pid);
+      m_executable_name = prpsinfo.pr_fname;
+      break;
+    }
+    case ELF::NT_SIGINFO: {
+      lldb::offset_t size = note.data.GetByteSize();
+      lldb::offset_t offset = 0;
+      const char *bytes =
+          static_cast<const char *>(note.data.GetData(&offset, size));
+      thread_data.siginfo_bytes = llvm::StringRef(bytes, size);
+      break;
+    }
+    case ELF::NT_FILE: {
+      m_nt_file_entries.clear();
+      lldb::offset_t offset = 0;
+      const uint64_t count = note.data.GetAddress(&offset);
+      note.data.GetAddress(&offset); // Skip page size
+      for (uint64_t i = 0; i < count; ++i) {
+        NT_FILE_Entry entry;
+        entry.start = note.data.GetAddress(&offset);
+        entry.end = note.data.GetAddress(&offset);
+        entry.file_ofs = note.data.GetAddress(&offset);
+        m_nt_file_entries.push_back(entry);
+      }
+      for (uint64_t i = 0; i < count; ++i) {
+        const char *path = note.data.GetCStr(&offset);
+        if (path && path[0])
+          m_nt_file_entries[i].path.assign(path);
+      }
+      break;
+    }
+    case ELF::NT_AUXV:
+      m_auxv = note.data;
+      break;
+    default:
+      thread_data.notes.push_back(note);
+      break;
+    }
+  }
+  // Add last entry in the note section
+  if (have_prstatus)
+    m_thread_data.push_back(thread_data);
+  return llvm::Error::success();
+}
+
+/// Parse Thread context from PT_NOTE segment and store it in the thread list
+/// A note segment consists of one or more NOTE entries, but their types and
+/// meaning differ depending on the OS.
+llvm::Error ProcessElfCore::ParseThreadContextsFromNoteSegment(
+    const elf::ELFProgramHeader &segment_header,
+    const DataExtractor &segment_data) {
+  assert(segment_header.p_type == llvm::ELF::PT_NOTE);
+
+  auto notes_or_error = parseSegment(segment_data);
+  if(!notes_or_error)
+    return notes_or_error.takeError();
+  switch (GetArchitecture().GetTriple().getOS()) {
+  case llvm::Triple::FreeBSD:
+    return parseFreeBSDNotes(*notes_or_error);
+  case llvm::Triple::Linux:
+    return parseLinuxNotes(*notes_or_error);
+  case llvm::Triple::NetBSD:
+    return parseNetBSDNotes(*notes_or_error);
+  case llvm::Triple::OpenBSD:
+    return parseOpenBSDNotes(*notes_or_error);
+  default:
+    return llvm::make_error<llvm::StringError>(
+        "Don't know how to parse core file. Unsupported OS.",
+        llvm::inconvertibleErrorCode());
+  }
+}
+
+UUID ProcessElfCore::FindBuidIdInCoreMemory(lldb::addr_t address) {
+  UUID invalid_uuid;
+  const uint32_t addr_size = GetAddressByteSize();
+  const size_t elf_header_size = addr_size == 4 ? sizeof(llvm::ELF::Elf32_Ehdr)
+                                                : sizeof(llvm::ELF::Elf64_Ehdr);
+
+  std::vector<uint8_t> elf_header_bytes;
+  elf_header_bytes.resize(elf_header_size);
+  Status error;
+  size_t byte_read =
+      ReadMemory(address, elf_header_bytes.data(), elf_header_size, error);
+  if (byte_read != elf_header_size ||
+      !elf::ELFHeader::MagicBytesMatch(elf_header_bytes.data()))
+    return invalid_uuid;
+  DataExtractor elf_header_data(elf_header_bytes.data(), elf_header_size,
+                                GetByteOrder(), addr_size);
+  lldb::offset_t offset = 0;
+
+  elf::ELFHeader elf_header;
+  elf_header.Parse(elf_header_data, &offset);
+
+  const lldb::addr_t ph_addr = address + elf_header.e_phoff;
+
+  std::vector<uint8_t> ph_bytes;
+  ph_bytes.resize(elf_header.e_phentsize);
+  lldb::addr_t base_addr = 0;
+  bool found_first_load_segment = false;
+  for (unsigned int i = 0; i < elf_header.e_phnum; ++i) {
+    byte_read = ReadMemory(ph_addr + i * elf_header.e_phentsize,
+                           ph_bytes.data(), elf_header.e_phentsize, error);
+    if (byte_read != elf_header.e_phentsize)
+      break;
+    DataExtractor program_header_data(ph_bytes.data(), elf_header.e_phentsize,
+                                      GetByteOrder(), addr_size);
+    offset = 0;
+    elf::ELFProgramHeader program_header;
+    program_header.Parse(program_header_data, &offset);
+    if (program_header.p_type == llvm::ELF::PT_LOAD &&
+        !found_first_load_segment) {
+      base_addr = program_header.p_vaddr;
+      found_first_load_segment = true;
+    }
+    if (program_header.p_type != llvm::ELF::PT_NOTE)
+      continue;
+
+    std::vector<uint8_t> note_bytes;
+    note_bytes.resize(program_header.p_memsz);
+
+    // We need to slide the address of the p_vaddr as these values don't get
+    // relocated in memory.
+    const lldb::addr_t vaddr = program_header.p_vaddr + address - base_addr;
+    byte_read =
+        ReadMemory(vaddr, note_bytes.data(), program_header.p_memsz, error);
+    if (byte_read != program_header.p_memsz)
+      continue;
+    DataExtractor segment_data(note_bytes.data(), note_bytes.size(),
+                               GetByteOrder(), addr_size);
+    auto notes_or_error = parseSegment(segment_data);
+    if (!notes_or_error) {
+      llvm::consumeError(notes_or_error.takeError());
+      return invalid_uuid;
+    }
+    for (const CoreNote &note : *notes_or_error) {
+      if (note.info.n_namesz == 4 &&
+          note.info.n_type == llvm::ELF::NT_GNU_BUILD_ID &&
+          "GNU" == note.info.n_name &&
+          note.data.ValidOffsetForDataOfSize(0, note.info.n_descsz))
+        return UUID(note.data.GetData().take_front(note.info.n_descsz));
+    }
+  }
+  return invalid_uuid;
+}
+
+uint32_t ProcessElfCore::GetNumThreadContexts() {
+  if (!m_thread_data_valid)
+    DoLoadCore();
+  return m_thread_data.size();
+}
+
+ArchSpec ProcessElfCore::GetArchitecture() {
+  ArchSpec arch = m_core_module_sp->GetObjectFile()->GetArchitecture();
+
+  ArchSpec target_arch = GetTarget().GetArchitecture();
+  arch.MergeFrom(target_arch);
+
+  // On MIPS there is no way to differentiate betwenn 32bit and 64bit core
+  // files and this information can't be merged in from the target arch so we
+  // fail back to unconditionally returning the target arch in this config.
+  if (target_arch.IsMIPS()) {
+    return target_arch;
+  }
+
+  return arch;
+}
+
+DataExtractor ProcessElfCore::GetAuxvData() {
+  assert(m_auxv.GetByteSize() == 0 ||
+         (m_auxv.GetByteOrder() == GetByteOrder() &&
+          m_auxv.GetAddressByteSize() == GetAddressByteSize()));
+  return DataExtractor(m_auxv);
+}
+
+bool ProcessElfCore::GetProcessInfo(ProcessInstanceInfo &info) {
+  info.Clear();
+  info.SetProcessID(GetID());
+  info.SetArchitecture(GetArchitecture());
+  lldb::ModuleSP module_sp = GetTarget().GetExecutableModule();
+  if (module_sp) {
+    const bool add_exe_file_as_first_arg = false;
+    info.SetExecutableFile(GetTarget().GetExecutableModule()->GetFileSpec(),
+                           add_exe_file_as_first_arg);
+  }
+  return true;
+}
diff --git a/lldb/source/Plugins/Process/elf-core/ProcessElfCore.h b/lldb/source/Plugins/Process/elf-core/ProcessElfCore.h
index a91c04a277f60..a246cdfaac398 100644
--- a/lldb/source/Plugins/Process/elf-core/ProcessElfCore.h
+++ b/lldb/source/Plugins/Process/elf-core/ProcessElfCore.h
@@ -17,6 +17,7 @@
 #define LLDB_SOURCE_PLUGINS_PROCESS_ELF_CORE_PROCESSELFCORE_H
 
 #include <list>
+#include <unordered_map>
 #include <vector>
 
 #include "lldb/Target/PostMortemProcess.h"
@@ -152,6 +153,12 @@ class ProcessElfCore : public lldb_private::PostMortemProcess {
   // NT_FILE entries found from the NOTE segment
   std::vector<NT_FILE_Entry> m_nt_file_entries;
 
+  // Map from file path to UUID for quick lookup
+  std::unordered_map<std::string, lldb_private::UUID> m_uuids;
+
+  // Executable name found from the ELF PRPSINFO
+  std::string m_executable_name;
+
   // Parse thread(s) data structures(prstatus, prpsinfo) from given NOTE segment
   llvm::Error ParseThreadContextsFromNoteSegment(
       const elf::ELFProgramHeader &segment_header,
@@ -165,6 +172,9 @@ class ProcessElfCore : public lldb_private::PostMortemProcess {
 
   lldb_private::UUID FindModuleUUID(const llvm::StringRef path) override;
 
+  // Returns the main executable path
+  llvm::StringRef GetMainExecutablePath();
+
   // Returns the value of certain type of note of a given start address
   lldb_private::UUID FindBuidIdInCoreMemory(lldb::addr_t address);
 



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