[XCOFF] Add functionality for parsing AIX XCOFF object file headers

Summary:
1. Add functionality for parsing AIX XCOFF object files headers.
2. Only support 32-bit AIX XCOFF object files in this patch.
3. Print out the AIX XCOFF object file header in YAML format.

Reviewers: sfertile, hubert.reinterpretcast, jasonliu, mstorsjo, zturner, rnk

Reviewed By: sfertile, hubert.reinterpretcast

Subscribers: jsji, mgorny, hiraditya, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59419

Patch by Digger Lin


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357663 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Object/XCOFFObjectFile.cpp

@@ -0,0 +1,270 @@
+//===--- XCOFFObjectFile.cpp - XCOFF object file implementation -----------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the XCOFFObjectFile class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Object/XCOFFObjectFile.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/Support/BinaryStreamReader.h"
+#include "llvm/Support/Endian.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MathExtras.h"
+#include <cstddef>
+#include <cstring>
+
+namespace llvm {
+namespace object {
+
+// Sets Obj unless any bytes in [addr, addr + size) fall outsize of m.
+// Returns unexpected_eof on error.
+template <typename T>
+static std::error_code getObject(const T *&Obj, MemoryBufferRef M,
+                                 const void *Ptr,
+                                 const uint64_t Size = sizeof(T)) {
+  uintptr_t Addr = uintptr_t(Ptr);
+  if (std::error_code EC = Binary::checkOffset(M, Addr, Size))
+    return EC;
+  Obj = reinterpret_cast<const T *>(Addr);
+  return std::error_code();
+}
+
+void XCOFFObjectFile::moveSymbolNext(DataRefImpl &Symb) const {
+  llvm_unreachable("Not yet implemented!");
+  return;
+}
+
+Expected<StringRef> XCOFFObjectFile::getSymbolName(DataRefImpl Symb) const {
+  StringRef Result;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+Expected<uint64_t> XCOFFObjectFile::getSymbolAddress(DataRefImpl Symb) const {
+  uint64_t Result = 0;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+uint64_t XCOFFObjectFile::getSymbolValueImpl(DataRefImpl Symb) const {
+  uint64_t Result = 0;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+uint64_t XCOFFObjectFile::getCommonSymbolSizeImpl(DataRefImpl Symb) const {
+  uint64_t Result = 0;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+Expected<SymbolRef::Type>
+XCOFFObjectFile::getSymbolType(DataRefImpl Symb) const {
+  llvm_unreachable("Not yet implemented!");
+  return SymbolRef::ST_Other;
+}
+
+Expected<section_iterator>
+XCOFFObjectFile::getSymbolSection(DataRefImpl Symb) const {
+  llvm_unreachable("Not yet implemented!");
+  return section_iterator(SectionRef());
+}
+
+void XCOFFObjectFile::moveSectionNext(DataRefImpl &Sec) const {
+  llvm_unreachable("Not yet implemented!");
+  return;
+}
+
+std::error_code XCOFFObjectFile::getSectionName(DataRefImpl Sec,
+                                                StringRef &Res) const {
+  llvm_unreachable("Not yet implemented!");
+  return std::error_code();
+}
+
+uint64_t XCOFFObjectFile::getSectionAddress(DataRefImpl Sec) const {
+  uint64_t Result = 0;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+uint64_t XCOFFObjectFile::getSectionIndex(DataRefImpl Sec) const {
+  uint64_t Result = 0;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+uint64_t XCOFFObjectFile::getSectionSize(DataRefImpl Sec) const {
+  uint64_t Result = 0;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+std::error_code XCOFFObjectFile::getSectionContents(DataRefImpl Sec,
+                                                    StringRef &Res) const {
+  llvm_unreachable("Not yet implemented!");
+  return std::error_code();
+}
+
+uint64_t XCOFFObjectFile::getSectionAlignment(DataRefImpl Sec) const {
+  uint64_t Result = 0;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+bool XCOFFObjectFile::isSectionCompressed(DataRefImpl Sec) const {
+  bool Result = false;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+bool XCOFFObjectFile::isSectionText(DataRefImpl Sec) const {
+  bool Result = false;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+bool XCOFFObjectFile::isSectionData(DataRefImpl Sec) const {
+  bool Result = false;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+bool XCOFFObjectFile::isSectionBSS(DataRefImpl Sec) const {
+  bool Result = false;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+bool XCOFFObjectFile::isSectionVirtual(DataRefImpl Sec) const {
+  bool Result = false;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+relocation_iterator XCOFFObjectFile::section_rel_begin(DataRefImpl Sec) const {
+  llvm_unreachable("Not yet implemented!");
+  return relocation_iterator(RelocationRef());
+}
+
+relocation_iterator XCOFFObjectFile::section_rel_end(DataRefImpl Sec) const {
+  llvm_unreachable("Not yet implemented!");
+  return relocation_iterator(RelocationRef());
+}
+
+void XCOFFObjectFile::moveRelocationNext(DataRefImpl &Rel) const {
+  llvm_unreachable("Not yet implemented!");
+  return;
+}
+
+uint64_t XCOFFObjectFile::getRelocationOffset(DataRefImpl Rel) const {
+  llvm_unreachable("Not yet implemented!");
+  uint64_t Result = 0;
+  return Result;
+}
+
+symbol_iterator XCOFFObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
+  llvm_unreachable("Not yet implemented!");
+  return symbol_iterator(SymbolRef());
+}
+
+uint64_t XCOFFObjectFile::getRelocationType(DataRefImpl Rel) const {
+  llvm_unreachable("Not yet implemented!");
+  uint64_t Result = 0;
+  return Result;
+}
+
+void XCOFFObjectFile::getRelocationTypeName(
+    DataRefImpl Rel, SmallVectorImpl<char> &Result) const {
+  llvm_unreachable("Not yet implemented!");
+  return;
+}
+
+uint32_t XCOFFObjectFile::getSymbolFlags(DataRefImpl Symb) const {
+  uint32_t Result = 0;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+basic_symbol_iterator XCOFFObjectFile::symbol_begin() const {
+  llvm_unreachable("Not yet implemented!");
+  return basic_symbol_iterator(SymbolRef());
+}
+
+basic_symbol_iterator XCOFFObjectFile::symbol_end() const {
+  llvm_unreachable("Not yet implemented!");
+  return basic_symbol_iterator(SymbolRef());
+}
+
+section_iterator XCOFFObjectFile::section_begin() const {
+  llvm_unreachable("Not yet implemented!");
+  return section_iterator(SectionRef());
+}
+
+section_iterator XCOFFObjectFile::section_end() const {
+  llvm_unreachable("Not yet implemented!");
+  return section_iterator(SectionRef());
+}
+
+uint8_t XCOFFObjectFile::getBytesInAddress() const {
+  uint8_t Result = 0;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+StringRef XCOFFObjectFile::getFileFormatName() const {
+  llvm_unreachable("Not yet implemented!");
+  return "";
+}
+
+Triple::ArchType XCOFFObjectFile::getArch() const {
+  llvm_unreachable("Not yet implemented!");
+  return Triple::UnknownArch;
+}
+
+SubtargetFeatures XCOFFObjectFile::getFeatures() const {
+  llvm_unreachable("Not yet implemented!");
+  return SubtargetFeatures();
+}
+
+bool XCOFFObjectFile::isRelocatableObject() const {
+  bool Result = false;
+  llvm_unreachable("Not yet implemented!");
+  return Result;
+}
+
+XCOFFObjectFile::XCOFFObjectFile(MemoryBufferRef Object, std::error_code &EC)
+    : ObjectFile(Binary::ID_XCOFF32, Object) {
+
+  // Current location within the file.
+  uint64_t CurPtr = 0;
+
+  if ((EC = getObject(FileHdrPtr, Data, base() + CurPtr)))
+    return;
+}
+
+Expected<std::unique_ptr<ObjectFile>>
+ObjectFile::createXCOFFObjectFile(MemoryBufferRef Object) {
+  StringRef Data = Object.getBuffer();
+  file_magic Type = identify_magic(Data);
+  std::error_code EC;
+  std::unique_ptr<ObjectFile> Ret;
+
+  if (Type == file_magic::xcoff_object_32) {
+    Ret.reset(new XCOFFObjectFile(Object, EC));
+  } else {
+    llvm_unreachable("Encountered an unexpected binary file type!");
+  }
+
+  if (EC)
+    return errorCodeToError(EC);
+  return std::move(Ret);
+}
+
+} // namespace object
+} // namespace llvm