[Lldb-commits] [lldb] [lldb][AIX] Added XCOFF Object File Header for AIX (PR #111814)

[Dhruv Srivastava via lldb-commits]

================
@@ -0,0 +1,193 @@
+//===-- ObjectFileXCOFF.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 "ObjectFileXCOFF.h"
+
+#include <algorithm>
+#include <cassert>
+#include <cstring>
+#include <unordered_map>
+
+#include "lldb/Core/Module.h"
+#include "lldb/Core/ModuleSpec.h"
+#include "lldb/Core/PluginManager.h"
+#include "lldb/Core/Progress.h"
+#include "lldb/Core/Section.h"
+#include "lldb/Host/FileSystem.h"
+#include "lldb/Symbol/SymbolContext.h"
+#include "lldb/Target/Process.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Utility/ArchSpec.h"
+#include "lldb/Utility/DataBufferHeap.h"
+#include "lldb/Utility/FileSpecList.h"
+#include "lldb/Utility/LLDBLog.h"
+#include "lldb/Utility/Log.h"
+#include "lldb/Utility/RangeMap.h"
+#include "lldb/Utility/Status.h"
+#include "lldb/Utility/Stream.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/BinaryFormat/XCOFF.h"
+#include "llvm/Object/XCOFFObjectFile.h"
+#include "llvm/Support/MemoryBuffer.h"
+
+using namespace llvm;
+using namespace lldb;
+using namespace lldb_private;
+
+LLDB_PLUGIN_DEFINE(ObjectFileXCOFF)
+
+// FIXME: target 64bit at this moment.
+
+// Static methods.
+void ObjectFileXCOFF::Initialize() {
+  PluginManager::RegisterPlugin(GetPluginNameStatic(),
+                                GetPluginDescriptionStatic(), CreateInstance,
+                                CreateMemoryInstance, GetModuleSpecifications);
+}
+
+void ObjectFileXCOFF::Terminate() {
+  PluginManager::UnregisterPlugin(CreateInstance);
+}
+
+ObjectFile *ObjectFileXCOFF::CreateInstance(const lldb::ModuleSP &module_sp,
+                                            DataBufferSP data_sp,
+                                            lldb::offset_t data_offset,
+                                            const lldb_private::FileSpec *file,
+                                            lldb::offset_t file_offset,
+                                            lldb::offset_t length) {
+  if (!data_sp) {
+    data_sp = MapFileData(*file, length, file_offset);
+    if (!data_sp)
+      return nullptr;
+    data_offset = 0;
+  }
+  if (!ObjectFileXCOFF::MagicBytesMatch(data_sp, data_offset, length))
+    return nullptr;
+  // Update the data to contain the entire file if it doesn't already
+  if (data_sp->GetByteSize() < length) {
+    data_sp = MapFileData(*file, length, file_offset);
+    if (!data_sp)
+      return nullptr;
+    data_offset = 0;
+  }
+  auto objfile_up = std::make_unique<ObjectFileXCOFF>(
+      module_sp, data_sp, data_offset, file, file_offset, length);
+  if (!objfile_up)
+    return nullptr;
+
+  return objfile_up.release();
+}
+
+ObjectFile *ObjectFileXCOFF::CreateMemoryInstance(
+    const lldb::ModuleSP &module_sp, WritableDataBufferSP data_sp,
+    const lldb::ProcessSP &process_sp, lldb::addr_t header_addr) {
+  return nullptr;
+}
+
+size_t ObjectFileXCOFF::GetModuleSpecifications(
+    const lldb_private::FileSpec &file, lldb::DataBufferSP &data_sp,
+    lldb::offset_t data_offset, lldb::offset_t file_offset,
+    lldb::offset_t length, lldb_private::ModuleSpecList &specs) {
+  const size_t initial_count = specs.GetSize();
+
+  if (ObjectFileXCOFF::MagicBytesMatch(data_sp, 0, data_sp->GetByteSize())) {
+    ArchSpec arch_spec =
+        ArchSpec(eArchTypeXCOFF, XCOFF::TCPU_PPC64, LLDB_INVALID_CPUTYPE);
+    ModuleSpec spec(file, arch_spec);
+    spec.GetArchitecture().SetArchitecture(eArchTypeXCOFF, XCOFF::TCPU_PPC64,
+                                           LLDB_INVALID_CPUTYPE,
+                                           llvm::Triple::AIX);
+    specs.Append(spec);
+  }
+  return specs.GetSize() - initial_count;
+}
+
+static uint32_t XCOFFHeaderSizeFromMagic(uint32_t magic) {
+  switch (magic) {
+    /* TODO: 32bit not supported yet
+    case XCOFF::XCOFF32:
+      return sizeof(struct llvm::object::XCOFFFileHeader32);
+    */
+
+  case XCOFF::XCOFF64:
+    return sizeof(struct llvm::object::XCOFFFileHeader64);
+    break;
+
+  default:
+    break;
+  }
+  return 0;
+}
+
+bool ObjectFileXCOFF::MagicBytesMatch(DataBufferSP &data_sp,
+                                      lldb::addr_t data_offset,
+                                      lldb::addr_t data_length) {
+  lldb_private::DataExtractor data;
+  data.SetData(data_sp, data_offset, data_length);
+  lldb::offset_t offset = 0;
+  uint16_t magic = data.GetU16(&offset);
+  if (magic == 0xF701)
+    magic = 0x01F7; /* Since AIX is big endian, and the host checking platform
+                       might be little endian. */
----------------
DhruvSrivastavaX wrote:

Great. Done, Thanks!

https://github.com/llvm/llvm-project/pull/111814