[yaml2obj] Initial ELF support.

Currently, only emitting the ELF header is supported (no sections or
segments).

The ELFYAML code organization is broadly similar to the COFFYAML code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183711 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 92 insertions, 0 deletions

diff --git a/include/llvm/Object/ELFYAML.h b/include/llvm/Object/ELFYAML.h
new file mode 100644
index 0000000..18eacce
--- /dev/null
+++ b/include/llvm/Object/ELFYAML.h
@@ -0,0 +1,92 @@
+//===- ELFYAML.h - ELF YAMLIO implementation --------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief This file declares classes for handling the YAML representation
+/// of ELF.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_OBJECT_ELFYAML_H
+#define LLVM_OBJECT_ELFYAML_H
+
+#include "llvm/Object/YAML.h"
+#include "llvm/Support/ELF.h"
+
+namespace llvm {
+namespace ELFYAML {
+
+// These types are invariant across 32/64-bit ELF, so for simplicity just
+// directly give them their exact sizes. We don't need to worry about
+// endianness because these are just the types in the YAMLIO structures,
+// and are appropriately converted to the necessary endianness when
+// reading/generating binary object files.
+// The naming of these types is intended to be ELF_PREFIX, where PREFIX is
+// the common prefix of the respective constants. E.g. ELF_EM corresponds
+// to the `e_machine` constants, like `EM_X86_64`.
+// In the future, these would probably be better suited by C++11 enum
+// class's with appropriate fixed underlying type.
+LLVM_YAML_STRONG_TYPEDEF(uint16_t, ELF_ET);
+LLVM_YAML_STRONG_TYPEDEF(uint32_t, ELF_EM);
+LLVM_YAML_STRONG_TYPEDEF(uint8_t, ELF_ELFCLASS);
+LLVM_YAML_STRONG_TYPEDEF(uint8_t, ELF_ELFDATA);
+
+// For now, hardcode 64 bits everywhere that 32 or 64 would be needed
+// since 64-bit can hold 32-bit values too.
+struct Header {
+  ELF_ELFCLASS Class;
+  ELF_ELFDATA Data;
+  ELF_ET Type;
+  ELF_EM Machine;
+  llvm::yaml::Hex64 Entry;
+};
+struct Object {
+  Header Header;
+};
+
+} // end namespace ELFYAML
+} // end namespace llvm
+
+namespace llvm {
+namespace yaml {
+
+template <>
+struct ScalarEnumerationTraits<ELFYAML::ELF_ET> {
+  static void enumeration(IO &IO, ELFYAML::ELF_ET &Value);
+};
+
+template <>
+struct ScalarEnumerationTraits<ELFYAML::ELF_EM> {
+  static void enumeration(IO &IO, ELFYAML::ELF_EM &Value);
+};
+
+template <>
+struct ScalarEnumerationTraits<ELFYAML::ELF_ELFCLASS> {
+  static void enumeration(IO &IO, ELFYAML::ELF_ELFCLASS &Value);
+};
+
+template <>
+struct ScalarEnumerationTraits<ELFYAML::ELF_ELFDATA> {
+  static void enumeration(IO &IO, ELFYAML::ELF_ELFDATA &Value);
+};
+
+template <>
+struct MappingTraits<ELFYAML::Header> {
+  static void mapping(IO &IO, ELFYAML::Header &Header);
+};
+
+template <>
+struct MappingTraits<ELFYAML::Object> {
+  static void mapping(IO &IO, ELFYAML::Object &Object);
+};
+
+} // end namespace yaml
+} // end namespace llvm
+
+#endif