Update from chromium 62675d9fb31fb8cedc40f68e78e8445a74f362e7

tools/relocation_packer/src/elf_traits.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Target-specific ELF type traits.
+
+#ifndef TOOLS_RELOCATION_PACKER_SRC_ELF_TRAITS_H_
+#define TOOLS_RELOCATION_PACKER_SRC_ELF_TRAITS_H_
+
+#include "elf.h"
+#include "libelf.h"
+
+// The TARGET_ macro controls which Elf types we expect and handle.
+// Either TARGET_ARM or TARGET_ARM64 must be defined, but not both.
+
+#if !defined(TARGET_ARM) && !defined(TARGET_ARM64)
+# error "Unsupported target, define one of TARGET_ARM or TARGET_ARM64"
+#elif defined(TARGET_ARM) && defined(TARGET_ARM64)
+# error "Define one of TARGET_ARM or TARGET_ARM64, but not both"
+#endif
+
+// TODO(simonb): Eliminate these once AARCH64 appears reliably in elf.h.
+#ifndef EM_AARCH64
+#define EM_AARCH64 183
+#endif
+#ifndef R_AARCH64_RELATIVE
+#define R_AARCH64_RELATIVE 1027
+#endif
+#ifndef R_AARCH64_NONE
+#define R_AARCH64_NONE 0
+#endif
+
+// ELF is a traits structure used to provide convenient aliases for
+// 32/64 bit Elf types and functions, depending on the target specified.
+
+#if defined(TARGET_ARM)
+struct ELF {
+  typedef Elf32_Addr Addr;
+  typedef Elf32_Dyn Dyn;
+  typedef Elf32_Ehdr Ehdr;
+  typedef Elf32_Off Off;
+  typedef Elf32_Phdr Phdr;
+  typedef Elf32_Rel Rel;
+  typedef Elf32_Rela Rela;
+  typedef Elf32_Shdr Shdr;
+  typedef Elf32_Sword Sword;
+  typedef Elf32_Sxword Sxword;
+  typedef Elf32_Sym Sym;
+  typedef Elf32_Word Word;
+  typedef Elf32_Xword Xword;
+
+  static inline Ehdr* getehdr(Elf* elf) { return elf32_getehdr(elf); }
+  static inline Phdr* getphdr(Elf* elf) { return elf32_getphdr(elf); }
+  static inline Shdr* getshdr(Elf_Scn* scn) { return elf32_getshdr(scn); }
+
+  enum { kMachine = EM_ARM };
+  enum { kFileClass = ELFCLASS32 };
+  enum { kRelativeRelocationCode = R_ARM_RELATIVE };
+  enum { kNoRelocationCode = R_ARM_NONE };
+  enum { kGnuStackSegmentAlignment = 0 };
+
+  static inline const char* Machine() { return "ARM"; }
+
+# define ELF_R_SYM(val) ELF32_R_SYM(val)
+# define ELF_R_TYPE(val) ELF32_R_TYPE(val)
+# define ELF_R_INFO(sym, type) ELF32_R_INFO(sym, type)
+# define ELF_ST_TYPE(val) ELF32_ST_TYPE(val)
+};
+
+#elif defined(TARGET_ARM64)
+struct ELF {
+  typedef Elf64_Addr Addr;
+  typedef Elf64_Dyn Dyn;
+  typedef Elf64_Ehdr Ehdr;
+  typedef Elf64_Off Off;
+  typedef Elf64_Phdr Phdr;
+  typedef Elf64_Rel Rel;
+  typedef Elf64_Rela Rela;
+  typedef Elf64_Shdr Shdr;
+  typedef Elf64_Sword Sword;
+  typedef Elf64_Sxword Sxword;
+  typedef Elf64_Sym Sym;
+  typedef Elf64_Word Word;
+  typedef Elf64_Xword Xword;
+
+  static inline Ehdr* getehdr(Elf* elf) { return elf64_getehdr(elf); }
+  static inline Phdr* getphdr(Elf* elf) { return elf64_getphdr(elf); }
+  static inline Shdr* getshdr(Elf_Scn* scn) { return elf64_getshdr(scn); }
+
+  enum { kMachine = EM_AARCH64 };
+  enum { kFileClass = ELFCLASS64 };
+  enum { kRelativeRelocationCode = R_AARCH64_RELATIVE };
+  enum { kNoRelocationCode = R_AARCH64_NONE };
+  enum { kGnuStackSegmentAlignment = 16 };
+
+  static inline const char* Machine() { return "ARM64"; }
+
+# define ELF_R_SYM(val) ELF64_R_SYM(val)
+# define ELF_R_TYPE(val) ELF64_R_TYPE(val)
+# define ELF_R_INFO(sym, type) ELF64_R_INFO(sym, type)
+# define ELF_ST_TYPE(val) ELF64_ST_TYPE(val)
+};
+#endif
+
+#endif  // TOOLS_RELOCATION_PACKER_SRC_ELF_TRAITS_H_