Create libelffile library for ELF file manipulation.

Move some of our tooling to library to make it reusable.

Remove MIPS support from the ELF builder.  This is slightly
easier than making it independent of the runtime.

Bug: 110133331
Test: test.py -b --host
Change-Id: I93343808d0e27ee8e1117e713a2503e8179fc245

60 files changed, 255 insertions, 342 deletions

diff --git a/compiler/Android.bp b/compiler/Android.bp
index 341727dc0d..4ad59e121c 100644
--- a/compiler/Android.bp
+++ b/compiler/Android.bp
@@ -26,17 +26,12 @@ art_cc_defaults {
     srcs: [
         "compiled_method.cc",
         "debug/elf_debug_writer.cc",
-        "debug/xz_utils.cc",
         "dex/inline_method_analyser.cc",
         "dex/verified_method.cc",
         "dex/verification_results.cc",
         "driver/compiled_method_storage.cc",
         "driver/compiler_options.cc",
         "driver/dex_compilation_unit.cc",
-        "linker/buffered_output_stream.cc",
-        "linker/file_output_stream.cc",
-        "linker/output_stream.cc",
-        "linker/vector_output_stream.cc",
         "jit/jit_compiler.cc",
         "jit/jit_logger.cc",
         "jni/quick/calling_convention.cc",
@@ -254,6 +249,7 @@ art_cc_library {
         "libprofile",
         "libdexfile",
     ],
+    whole_static_libs: ["libelffile"],
 
     target: {
         android: {
@@ -317,6 +313,7 @@ art_cc_library {
         "libprofiled",
         "libdexfiled",
     ],
+    whole_static_libs: ["libelffiled"],
 }
 
 cc_defaults {
diff --git a/compiler/cfi_test.h b/compiler/cfi_test.h
index 2fc81c958a..9755ef12d0 100644
--- a/compiler/cfi_test.h
+++ b/compiler/cfi_test.h
@@ -23,10 +23,10 @@
 
 #include "arch/instruction_set.h"
 #include "base/enums.h"
-#include "debug/dwarf/dwarf_constants.h"
 #include "debug/dwarf/dwarf_test.h"
-#include "debug/dwarf/headers.h"
 #include "disassembler.h"
+#include "dwarf/dwarf_constants.h"
+#include "dwarf/headers.h"
 #include "gtest/gtest.h"
 #include "thread.h"
 
diff --git a/compiler/debug/dwarf/dwarf_test.cc b/compiler/debug/dwarf/dwarf_test.cc
index 5491596dd8..5946af8d55 100644
--- a/compiler/debug/dwarf/dwarf_test.cc
+++ b/compiler/debug/dwarf/dwarf_test.cc
@@ -16,11 +16,11 @@
 
 #include "dwarf_test.h"
 
-#include "debug/dwarf/debug_frame_opcode_writer.h"
-#include "debug/dwarf/debug_info_entry_writer.h"
-#include "debug/dwarf/debug_line_opcode_writer.h"
-#include "debug/dwarf/dwarf_constants.h"
-#include "debug/dwarf/headers.h"
+#include "dwarf/debug_frame_opcode_writer.h"
+#include "dwarf/debug_info_entry_writer.h"
+#include "dwarf/debug_line_opcode_writer.h"
+#include "dwarf/dwarf_constants.h"
+#include "dwarf/headers.h"
 #include "gtest/gtest.h"
 
 namespace art {
diff --git a/compiler/debug/dwarf/dwarf_test.h b/compiler/debug/dwarf/dwarf_test.h
index 6b039a7b5f..e51f807dd4 100644
--- a/compiler/debug/dwarf/dwarf_test.h
+++ b/compiler/debug/dwarf/dwarf_test.h
@@ -29,9 +29,9 @@
 #include "base/os.h"
 #include "base/unix_file/fd_file.h"
 #include "common_compiler_test.h"
+#include "elf/elf_builder.h"
 #include "gtest/gtest.h"
-#include "linker/elf_builder.h"
-#include "linker/file_output_stream.h"
+#include "stream/file_output_stream.h"
 
 namespace art {
 namespace dwarf {
@@ -63,8 +63,8 @@ class DwarfTest : public CommonCompilerTest {
     InstructionSet isa =
         (sizeof(typename ElfTypes::Addr) == 8) ? InstructionSet::kX86_64 : InstructionSet::kX86;
     ScratchFile file;
-    linker::FileOutputStream output_stream(file.GetFile());
-    linker::ElfBuilder<ElfTypes> builder(isa, nullptr, &output_stream);
+    FileOutputStream output_stream(file.GetFile());
+    ElfBuilder<ElfTypes> builder(isa, &output_stream);
     builder.Start();
     if (!debug_info_data_.empty()) {
       builder.WriteSection(".debug_info", &debug_info_data_);
diff --git a/compiler/debug/elf_debug_frame_writer.h b/compiler/debug/elf_debug_frame_writer.h
index 1f827eaefc..44b70ff930 100644
--- a/compiler/debug/elf_debug_frame_writer.h
+++ b/compiler/debug/elf_debug_frame_writer.h
@@ -20,11 +20,11 @@
 #include <vector>
 
 #include "arch/instruction_set.h"
-#include "debug/dwarf/debug_frame_opcode_writer.h"
-#include "debug/dwarf/dwarf_constants.h"
-#include "debug/dwarf/headers.h"
 #include "debug/method_debug_info.h"
-#include "linker/elf_builder.h"
+#include "dwarf/debug_frame_opcode_writer.h"
+#include "dwarf/dwarf_constants.h"
+#include "dwarf/headers.h"
+#include "elf/elf_builder.h"
 
 namespace art {
 namespace debug {
@@ -166,7 +166,7 @@ static void WriteCIE(InstructionSet isa, /*inout*/ std::vector<uint8_t>* buffer)
 }
 
 template<typename ElfTypes>
-void WriteCFISection(linker::ElfBuilder<ElfTypes>* builder,
+void WriteCFISection(ElfBuilder<ElfTypes>* builder,
                      const ArrayRef<const MethodDebugInfo>& method_infos) {
   typedef typename ElfTypes::Addr Elf_Addr;
 
diff --git a/compiler/debug/elf_debug_info_writer.h b/compiler/debug/elf_debug_info_writer.h
index 05a4a3e32b..8eead4ecef 100644
--- a/compiler/debug/elf_debug_info_writer.h
+++ b/compiler/debug/elf_debug_info_writer.h
@@ -22,17 +22,17 @@
 #include <vector>
 
 #include "art_field-inl.h"
-#include "debug/dwarf/debug_abbrev_writer.h"
-#include "debug/dwarf/debug_info_entry_writer.h"
 #include "debug/elf_compilation_unit.h"
 #include "debug/elf_debug_loc_writer.h"
 #include "debug/method_debug_info.h"
 #include "dex/code_item_accessors-inl.h"
 #include "dex/dex_file-inl.h"
 #include "dex/dex_file.h"
+#include "dwarf/debug_abbrev_writer.h"
+#include "dwarf/debug_info_entry_writer.h"
+#include "elf/elf_builder.h"
 #include "heap_poisoning.h"
 #include "linear_alloc.h"
-#include "linker/elf_builder.h"
 #include "mirror/array.h"
 #include "mirror/class-inl.h"
 #include "mirror/class.h"
@@ -59,7 +59,7 @@ class ElfDebugInfoWriter {
   using Elf_Addr = typename ElfTypes::Addr;
 
  public:
-  explicit ElfDebugInfoWriter(linker::ElfBuilder<ElfTypes>* builder)
+  explicit ElfDebugInfoWriter(ElfBuilder<ElfTypes>* builder)
       : builder_(builder),
         debug_abbrev_(&debug_abbrev_buffer_) {
   }
@@ -80,7 +80,7 @@ class ElfDebugInfoWriter {
   }
 
  private:
-  linker::ElfBuilder<ElfTypes>* builder_;
+  ElfBuilder<ElfTypes>* builder_;
   std::vector<uint8_t> debug_abbrev_buffer_;
   dwarf::DebugAbbrevWriter<> debug_abbrev_;
   std::vector<uint8_t> debug_loc_;
diff --git a/compiler/debug/elf_debug_line_writer.h b/compiler/debug/elf_debug_line_writer.h
index f95912a2d1..479725be99 100644
--- a/compiler/debug/elf_debug_line_writer.h
+++ b/compiler/debug/elf_debug_line_writer.h
@@ -20,12 +20,12 @@
 #include <unordered_set>
 #include <vector>
 
-#include "debug/dwarf/debug_line_opcode_writer.h"
-#include "debug/dwarf/headers.h"
 #include "debug/elf_compilation_unit.h"
 #include "debug/src_map_elem.h"
 #include "dex/dex_file-inl.h"
-#include "linker/elf_builder.h"
+#include "dwarf/debug_line_opcode_writer.h"
+#include "dwarf/headers.h"
+#include "elf/elf_builder.h"
 #include "oat_file.h"
 #include "stack_map.h"
 
@@ -39,7 +39,7 @@ class ElfDebugLineWriter {
   using Elf_Addr = typename ElfTypes::Addr;
 
  public:
-  explicit ElfDebugLineWriter(linker::ElfBuilder<ElfTypes>* builder) : builder_(builder) {
+  explicit ElfDebugLineWriter(ElfBuilder<ElfTypes>* builder) : builder_(builder) {
   }
 
   void Start() {
@@ -273,7 +273,7 @@ class ElfDebugLineWriter {
   }
 
  private:
-  linker::ElfBuilder<ElfTypes>* builder_;
+  ElfBuilder<ElfTypes>* builder_;
 };
 
 }  // namespace debug
diff --git a/compiler/debug/elf_debug_loc_writer.h b/compiler/debug/elf_debug_loc_writer.h
index b663291b4d..a5a84bbb10 100644
--- a/compiler/debug/elf_debug_loc_writer.h
+++ b/compiler/debug/elf_debug_loc_writer.h
@@ -22,9 +22,9 @@
 
 #include "arch/instruction_set.h"
 #include "compiled_method.h"
-#include "debug/dwarf/debug_info_entry_writer.h"
-#include "debug/dwarf/register.h"
 #include "debug/method_debug_info.h"
+#include "dwarf/debug_info_entry_writer.h"
+#include "dwarf/register.h"
 #include "stack_map.h"
 
 namespace art {
diff --git a/compiler/debug/elf_debug_writer.cc b/compiler/debug/elf_debug_writer.cc
index 3b7363be6a..cc74717edb 100644
--- a/compiler/debug/elf_debug_writer.cc
+++ b/compiler/debug/elf_debug_writer.cc
@@ -22,20 +22,20 @@
 
 #include "base/array_ref.h"
 #include "base/stl_util.h"
-#include "debug/dwarf/dwarf_constants.h"
 #include "debug/elf_compilation_unit.h"
 #include "debug/elf_debug_frame_writer.h"
 #include "debug/elf_debug_info_writer.h"
 #include "debug/elf_debug_line_writer.h"
 #include "debug/elf_debug_loc_writer.h"
-#include "debug/elf_debug_reader.h"
 #include "debug/elf_symtab_writer.h"
 #include "debug/method_debug_info.h"
-#include "debug/xz_utils.h"
-#include "elf.h"
-#include "linker/elf_builder.h"
-#include "linker/vector_output_stream.h"
+#include "dwarf/dwarf_constants.h"
+#include "elf/elf.h"
+#include "elf/elf_builder.h"
+#include "elf/elf_debug_reader.h"
+#include "elf/xz_utils.h"
 #include "oat.h"
+#include "stream/vector_output_stream.h"
 
 namespace art {
 namespace debug {
@@ -43,7 +43,7 @@ namespace debug {
 using ElfRuntimeTypes = std::conditional<sizeof(void*) == 4, ElfTypes32, ElfTypes64>::type;
 
 template <typename ElfTypes>
-void WriteDebugInfo(linker::ElfBuilder<ElfTypes>* builder,
+void WriteDebugInfo(ElfBuilder<ElfTypes>* builder,
                     const DebugInfo& debug_info) {
   // Write .strtab and .symtab.
   WriteDebugSymbols(builder, /* mini-debug-info= */ false, debug_info);
@@ -112,7 +112,7 @@ void WriteDebugInfo(linker::ElfBuilder<ElfTypes>* builder,
 template <typename ElfTypes>
 static std::vector<uint8_t> MakeMiniDebugInfoInternal(
     InstructionSet isa,
-    const InstructionSetFeatures* features,
+    const InstructionSetFeatures* features ATTRIBUTE_UNUSED,
     typename ElfTypes::Addr text_section_address,
     size_t text_section_size,
     typename ElfTypes::Addr dex_section_address,
@@ -120,9 +120,8 @@ static std::vector<uint8_t> MakeMiniDebugInfoInternal(
     const DebugInfo& debug_info) {
   std::vector<uint8_t> buffer;
   buffer.reserve(KB);
-  linker::VectorOutputStream out("Mini-debug-info ELF file", &buffer);
-  std::unique_ptr<linker::ElfBuilder<ElfTypes>> builder(
-      new linker::ElfBuilder<ElfTypes>(isa, features, &out));
+  VectorOutputStream out("Mini-debug-info ELF file", &buffer);
+  std::unique_ptr<ElfBuilder<ElfTypes>> builder(new ElfBuilder<ElfTypes>(isa, &out));
   builder->Start(/* write_program_headers= */ false);
   // Mirror ELF sections as NOBITS since the added symbols will reference them.
   if (text_section_size != 0) {
@@ -174,7 +173,7 @@ std::vector<uint8_t> MakeMiniDebugInfo(
 
 std::vector<uint8_t> MakeElfFileForJIT(
     InstructionSet isa,
-    const InstructionSetFeatures* features,
+    const InstructionSetFeatures* features ATTRIBUTE_UNUSED,
     bool mini_debug_info,
     const MethodDebugInfo& method_info) {
   using ElfTypes = ElfRuntimeTypes;
@@ -184,9 +183,8 @@ std::vector<uint8_t> MakeElfFileForJIT(
   debug_info.compiled_methods = ArrayRef<const MethodDebugInfo>(&method_info, 1);
   std::vector<uint8_t> buffer;
   buffer.reserve(KB);
-  linker::VectorOutputStream out("Debug ELF file", &buffer);
-  std::unique_ptr<linker::ElfBuilder<ElfTypes>> builder(
-      new linker::ElfBuilder<ElfTypes>(isa, features, &out));
+  VectorOutputStream out("Debug ELF file", &buffer);
+  std::unique_ptr<ElfBuilder<ElfTypes>> builder(new ElfBuilder<ElfTypes>(isa, &out));
   // No program headers since the ELF file is not linked and has no allocated sections.
   builder->Start(/* write_program_headers= */ false);
   builder->GetText()->AllocateVirtualMemory(method_info.code_address, method_info.code_size);
@@ -230,7 +228,7 @@ std::vector<uint8_t> MakeElfFileForJIT(
 // Combine several mini-debug-info ELF files into one, while filtering some symbols.
 std::vector<uint8_t> PackElfFileForJIT(
     InstructionSet isa,
-    const InstructionSetFeatures* features,
+    const InstructionSetFeatures* features ATTRIBUTE_UNUSED,
     std::vector<ArrayRef<const uint8_t>>& added_elf_files,
     std::vector<const void*>& removed_symbols,
     /*out*/ size_t* num_symbols) {
@@ -250,9 +248,8 @@ std::vector<uint8_t> PackElfFileForJIT(
   std::vector<uint8_t> inner_elf_file;
   {
     inner_elf_file.reserve(1 * KB);  // Approximate size of ELF file with a single symbol.
-    linker::VectorOutputStream out("Mini-debug-info ELF file for JIT", &inner_elf_file);
-    std::unique_ptr<linker::ElfBuilder<ElfTypes>> builder(
-        new linker::ElfBuilder<ElfTypes>(isa, features, &out));
+    VectorOutputStream out("Mini-debug-info ELF file for JIT", &inner_elf_file);
+    std::unique_ptr<ElfBuilder<ElfTypes>> builder(new ElfBuilder<ElfTypes>(isa, &out));
     builder->Start(/*write_program_headers=*/ false);
     auto* text = builder->GetText();
     auto* strtab = builder->GetStrTab();
@@ -328,9 +325,8 @@ std::vector<uint8_t> PackElfFileForJIT(
     XzCompress(ArrayRef<const uint8_t>(inner_elf_file), &gnu_debugdata);
 
     outer_elf_file.reserve(KB + gnu_debugdata.size());
-    linker::VectorOutputStream out("Mini-debug-info ELF file for JIT", &outer_elf_file);
-    std::unique_ptr<linker::ElfBuilder<ElfTypes>> builder(
-        new linker::ElfBuilder<ElfTypes>(isa, features, &out));
+    VectorOutputStream out("Mini-debug-info ELF file for JIT", &outer_elf_file);
+    std::unique_ptr<ElfBuilder<ElfTypes>> builder(new ElfBuilder<ElfTypes>(isa, &out));
     builder->Start(/*write_program_headers=*/ false);
     if (max_address > min_address) {
       builder->GetText()->AllocateVirtualMemory(min_address, max_address - min_address);
@@ -345,16 +341,15 @@ std::vector<uint8_t> PackElfFileForJIT(
 
 std::vector<uint8_t> WriteDebugElfFileForClasses(
     InstructionSet isa,
-    const InstructionSetFeatures* features,
+    const InstructionSetFeatures* features ATTRIBUTE_UNUSED,
     const ArrayRef<mirror::Class*>& types)
     REQUIRES_SHARED(Locks::mutator_lock_) {
   using ElfTypes = ElfRuntimeTypes;
   CHECK_EQ(sizeof(ElfTypes::Addr), static_cast<size_t>(GetInstructionSetPointerSize(isa)));
   std::vector<uint8_t> buffer;
   buffer.reserve(KB);
-  linker::VectorOutputStream out("Debug ELF file", &buffer);
-  std::unique_ptr<linker::ElfBuilder<ElfTypes>> builder(
-      new linker::ElfBuilder<ElfTypes>(isa, features, &out));
+  VectorOutputStream out("Debug ELF file", &buffer);
+  std::unique_ptr<ElfBuilder<ElfTypes>> builder(new ElfBuilder<ElfTypes>(isa, &out));
   // No program headers since the ELF file is not linked and has no allocated sections.
   builder->Start(/* write_program_headers= */ false);
   ElfDebugInfoWriter<ElfTypes> info_writer(builder.get());
@@ -370,10 +365,10 @@ std::vector<uint8_t> WriteDebugElfFileForClasses(
 
 // Explicit instantiations
 template void WriteDebugInfo<ElfTypes32>(
-    linker::ElfBuilder<ElfTypes32>* builder,
+    ElfBuilder<ElfTypes32>* builder,
     const DebugInfo& debug_info);
 template void WriteDebugInfo<ElfTypes64>(
-    linker::ElfBuilder<ElfTypes64>* builder,
+    ElfBuilder<ElfTypes64>* builder,
     const DebugInfo& debug_info);
 
 }  // namespace debug
diff --git a/compiler/debug/elf_debug_writer.h b/compiler/debug/elf_debug_writer.h
index 90580b4676..14a5edbace 100644
--- a/compiler/debug/elf_debug_writer.h
+++ b/compiler/debug/elf_debug_writer.h
@@ -19,12 +19,13 @@
 
 #include <vector>
 
+#include "arch/instruction_set_features.h"
 #include "base/array_ref.h"
 #include "base/macros.h"
 #include "base/mutex.h"
-#include "debug/dwarf/dwarf_constants.h"
 #include "debug/debug_info.h"
-#include "linker/elf_builder.h"
+#include "dwarf/dwarf_constants.h"
+#include "elf/elf_builder.h"
 
 namespace art {
 class OatHeader;
@@ -36,7 +37,7 @@ struct MethodDebugInfo;
 
 template <typename ElfTypes>
 void WriteDebugInfo(
-    linker::ElfBuilder<ElfTypes>* builder,
+    ElfBuilder<ElfTypes>* builder,
     const DebugInfo& debug_info);
 
 std::vector<uint8_t> MakeMiniDebugInfo(
diff --git a/compiler/debug/elf_symtab_writer.h b/compiler/debug/elf_symtab_writer.h
index 7a8e29191a..2ed3a4b1a4 100644
--- a/compiler/debug/elf_symtab_writer.h
+++ b/compiler/debug/elf_symtab_writer.h
@@ -25,7 +25,7 @@
 #include "debug/method_debug_info.h"
 #include "dex/dex_file-inl.h"
 #include "dex/code_item_accessors.h"
-#include "linker/elf_builder.h"
+#include "elf/elf_builder.h"
 
 namespace art {
 namespace debug {
@@ -45,7 +45,7 @@ constexpr bool kGenerateArmMappingSymbol = true;
 constexpr const char* kDexFileSymbolName = "$dexfile";
 
 template <typename ElfTypes>
-static void WriteDebugSymbols(linker::ElfBuilder<ElfTypes>* builder,
+static void WriteDebugSymbols(ElfBuilder<ElfTypes>* builder,
                               bool mini_debug_info,
                               const DebugInfo& debug_info) {
   uint64_t mapping_symbol_address = std::numeric_limits<uint64_t>::max();
diff --git a/compiler/jni/quick/jni_compiler.cc b/compiler/jni/quick/jni_compiler.cc
index bdbf4293f4..70540783b6 100644
--- a/compiler/jni/quick/jni_compiler.cc
+++ b/compiler/jni/quick/jni_compiler.cc
@@ -32,7 +32,7 @@
 #include "base/utils.h"
 #include "calling_convention.h"
 #include "class_linker.h"
-#include "debug/dwarf/debug_frame_opcode_writer.h"
+#include "dwarf/debug_frame_opcode_writer.h"
 #include "dex/dex_file-inl.h"
 #include "driver/compiler_options.h"
 #include "entrypoints/quick/quick_entrypoints.h"
diff --git a/compiler/linker/output_stream_test.cc b/compiler/linker/output_stream_test.cc
index bcb129c2da..00231b1240 100644
--- a/compiler/linker/output_stream_test.cc
+++ b/compiler/linker/output_stream_test.cc
@@ -14,15 +14,14 @@
  * limitations under the License.
  */
 
-#include "file_output_stream.h"
-#include "vector_output_stream.h"
-
 #include <android-base/logging.h>
 
 #include "base/macros.h"
 #include "base/unix_file/fd_file.h"
-#include "buffered_output_stream.h"
 #include "common_runtime_test.h"
+#include "stream/buffered_output_stream.h"
+#include "stream/file_output_stream.h"
+#include "stream/vector_output_stream.h"
 
 namespace art {
 namespace linker {
diff --git a/compiler/optimizing/common_arm.h b/compiler/optimizing/common_arm.h
index 356ff9f41f..7d3af9521a 100644
--- a/compiler/optimizing/common_arm.h
+++ b/compiler/optimizing/common_arm.h
@@ -17,7 +17,7 @@
 #ifndef ART_COMPILER_OPTIMIZING_COMMON_ARM_H_
 #define ART_COMPILER_OPTIMIZING_COMMON_ARM_H_
 
-#include "debug/dwarf/register.h"
+#include "dwarf/register.h"
 #include "instruction_simplifier_shared.h"
 #include "locations.h"
 #include "nodes.h"
diff --git a/compiler/utils/assembler.h b/compiler/utils/assembler.h
index 05372251dc..aa21f862de 100644
--- a/compiler/utils/assembler.h
+++ b/compiler/utils/assembler.h
@@ -30,7 +30,7 @@
 #include "base/enums.h"
 #include "base/macros.h"
 #include "base/memory_region.h"
-#include "debug/dwarf/debug_frame_opcode_writer.h"
+#include "dwarf/debug_frame_opcode_writer.h"
 #include "label.h"
 #include "managed_register.h"
 #include "mips/constants_mips.h"
diff --git a/dex2oat/dex2oat.cc b/dex2oat/dex2oat.cc
index 71f71d11e4..d04fa4e0d2 100644
--- a/dex2oat/dex2oat.cc
+++ b/dex2oat/dex2oat.cc
@@ -61,13 +61,13 @@
 #include "compiler_callbacks.h"
 #include "debug/elf_debug_writer.h"
 #include "debug/method_debug_info.h"
-#include "dexlayout.h"
 #include "dex/descriptors_names.h"
 #include "dex/dex_file-inl.h"
 #include "dex/quick_compiler_callbacks.h"
 #include "dex/verification_results.h"
 #include "dex2oat_options.h"
 #include "dex2oat_return_codes.h"
+#include "dexlayout.h"
 #include "driver/compiler_driver.h"
 #include "driver/compiler_options.h"
 #include "driver/compiler_options_map-inl.h"
@@ -77,10 +77,8 @@
 #include "gc/verification.h"
 #include "interpreter/unstarted_runtime.h"
 #include "jni/java_vm_ext.h"
-#include "linker/buffered_output_stream.h"
 #include "linker/elf_writer.h"
 #include "linker/elf_writer_quick.h"
-#include "linker/file_output_stream.h"
 #include "linker/image_writer.h"
 #include "linker/multi_oat_relative_patcher.h"
 #include "linker/oat_writer.h"
@@ -94,6 +92,8 @@
 #include "runtime.h"
 #include "runtime_options.h"
 #include "scoped_thread_state_change-inl.h"
+#include "stream/buffered_output_stream.h"
+#include "stream/file_output_stream.h"
 #include "vdex_file.h"
 #include "verifier/verifier_deps.h"
 #include "well_known_classes.h"
@@ -1323,9 +1323,9 @@ class Dex2Oat final {
     // Note: we're only invalidating the magic data in the file, as dex2oat needs the rest of
     // the information to remain valid.
     if (update_input_vdex_) {
-      std::unique_ptr<linker::BufferedOutputStream> vdex_out =
-          std::make_unique<linker::BufferedOutputStream>(
-              std::make_unique<linker::FileOutputStream>(vdex_files_.back().get()));
+      std::unique_ptr<BufferedOutputStream> vdex_out =
+          std::make_unique<BufferedOutputStream>(
+              std::make_unique<FileOutputStream>(vdex_files_.back().get()));
       if (!vdex_out->WriteFully(&VdexFile::VerifierDepsHeader::kVdexInvalidMagic,
                                 arraysize(VdexFile::VerifierDepsHeader::kVdexInvalidMagic))) {
         PLOG(ERROR) << "Failed to invalidate vdex header. File: " << vdex_out->GetLocation();
@@ -1962,9 +1962,9 @@ class Dex2Oat final {
       verifier::VerifierDeps* verifier_deps = callbacks_->GetVerifierDeps();
       for (size_t i = 0, size = oat_files_.size(); i != size; ++i) {
         File* vdex_file = vdex_files_[i].get();
-        std::unique_ptr<linker::BufferedOutputStream> vdex_out =
-            std::make_unique<linker::BufferedOutputStream>(
-                std::make_unique<linker::FileOutputStream>(vdex_file));
+        std::unique_ptr<BufferedOutputStream> vdex_out =
+            std::make_unique<BufferedOutputStream>(
+                std::make_unique<FileOutputStream>(vdex_file));
 
         if (!oat_writers_[i]->WriteVerifierDeps(vdex_out.get(), verifier_deps)) {
           LOG(ERROR) << "Failed to write verifier dependencies into VDEX " << vdex_file->GetPath();
@@ -2022,7 +2022,7 @@ class Dex2Oat final {
         debug::DebugInfo debug_info = oat_writer->GetDebugInfo();  // Keep the variable alive.
         elf_writer->PrepareDebugInfo(debug_info);  // Processes the data on background thread.
 
-        linker::OutputStream*& rodata = rodata_[i];
+        OutputStream*& rodata = rodata_[i];
         DCHECK(rodata != nullptr);
         if (!oat_writer->WriteRodata(rodata)) {
           LOG(ERROR) << "Failed to write .rodata section to the ELF file " << oat_file->GetPath();
@@ -2031,7 +2031,7 @@ class Dex2Oat final {
         elf_writer->EndRoData(rodata);
         rodata = nullptr;
 
-        linker::OutputStream* text = elf_writer->StartText();
+        OutputStream* text = elf_writer->StartText();
         if (!oat_writer->WriteCode(text)) {
           LOG(ERROR) << "Failed to write .text section to the ELF file " << oat_file->GetPath();
           return false;
@@ -2039,7 +2039,7 @@ class Dex2Oat final {
         elf_writer->EndText(text);
 
         if (oat_writer->GetDataBimgRelRoSize() != 0u) {
-          linker::OutputStream* data_bimg_rel_ro = elf_writer->StartDataBimgRelRo();
+          OutputStream* data_bimg_rel_ro = elf_writer->StartDataBimgRelRo();
           if (!oat_writer->WriteDataBimgRelRo(data_bimg_rel_ro)) {
             LOG(ERROR) << "Failed to write .data.bimg.rel.ro section to the ELF file "
                 << oat_file->GetPath();
@@ -2734,8 +2734,8 @@ class Dex2Oat final {
 
   std::vector<std::unique_ptr<linker::ElfWriter>> elf_writers_;
   std::vector<std::unique_ptr<linker::OatWriter>> oat_writers_;
-  std::vector<linker::OutputStream*> rodata_;
-  std::vector<std::unique_ptr<linker::OutputStream>> vdex_out_;
+  std::vector<OutputStream*> rodata_;
+  std::vector<std::unique_ptr<OutputStream>> vdex_out_;
   std::unique_ptr<linker::ImageWriter> image_writer_;
   std::unique_ptr<CompilerDriver> driver_;
 
diff --git a/dex2oat/linker/arm/relative_patcher_arm_base.cc b/dex2oat/linker/arm/relative_patcher_arm_base.cc
index a2ba339278..828dc5d7c3 100644
--- a/dex2oat/linker/arm/relative_patcher_arm_base.cc
+++ b/dex2oat/linker/arm/relative_patcher_arm_base.cc
@@ -21,9 +21,9 @@
 #include "debug/method_debug_info.h"
 #include "dex/dex_file_types.h"
 #include "linker/linker_patch.h"
-#include "linker/output_stream.h"
 #include "oat.h"
 #include "oat_quick_method_header.h"
+#include "stream/output_stream.h"
 
 namespace art {
 namespace linker {
diff --git a/dex2oat/linker/arm64/relative_patcher_arm64.cc b/dex2oat/linker/arm64/relative_patcher_arm64.cc
index 0497d4f966..ee8d4d1a7f 100644
--- a/dex2oat/linker/arm64/relative_patcher_arm64.cc
+++ b/dex2oat/linker/arm64/relative_patcher_arm64.cc
@@ -26,13 +26,13 @@
 #include "entrypoints/quick/quick_entrypoints_enum.h"
 #include "heap_poisoning.h"
 #include "linker/linker_patch.h"
-#include "linker/output_stream.h"
 #include "lock_word.h"
 #include "mirror/array-inl.h"
 #include "mirror/object.h"
 #include "oat.h"
 #include "oat_quick_method_header.h"
 #include "read_barrier.h"
+#include "stream/output_stream.h"
 #include "utils/arm64/assembler_arm64.h"
 
 namespace art {
diff --git a/dex2oat/linker/elf_writer.h b/dex2oat/linker/elf_writer.h
index 637330c835..a60c708bdb 100644
--- a/dex2oat/linker/elf_writer.h
+++ b/dex2oat/linker/elf_writer.h
@@ -31,6 +31,7 @@
 namespace art {
 
 class ElfFile;
+class OutputStream;
 
 namespace debug {
 struct MethodDebugInfo;
@@ -38,8 +39,6 @@ struct MethodDebugInfo;
 
 namespace linker {
 
-class OutputStream;
-
 class ElfWriter {
  public:
   // Looks up information about location of oat file in elf file container.
diff --git a/dex2oat/linker/elf_writer_quick.cc b/dex2oat/linker/elf_writer_quick.cc
index 7e0f29dfa2..65aa5a9887 100644
--- a/dex2oat/linker/elf_writer_quick.cc
+++ b/dex2oat/linker/elf_writer_quick.cc
@@ -31,11 +31,11 @@
 #include "debug/elf_debug_writer.h"
 #include "debug/method_debug_info.h"
 #include "driver/compiler_options.h"
-#include "elf.h"
+#include "elf/elf.h"
+#include "elf/elf_builder.h"
 #include "elf_utils.h"
-#include "linker/buffered_output_stream.h"
-#include "linker/elf_builder.h"
-#include "linker/file_output_stream.h"
+#include "stream/buffered_output_stream.h"
+#include "stream/file_output_stream.h"
 #include "thread-current-inl.h"
 #include "thread_pool.h"
 
@@ -159,7 +159,6 @@ ElfWriterQuick<ElfTypes>::ElfWriterQuick(const CompilerOptions& compiler_options
       output_stream_(
           std::make_unique<BufferedOutputStream>(std::make_unique<FileOutputStream>(elf_file))),
       builder_(new ElfBuilder<ElfTypes>(compiler_options_.GetInstructionSet(),
-                                        compiler_options_.GetInstructionSetFeatures(),
                                         output_stream_.get())) {}
 
 template <typename ElfTypes>
@@ -243,10 +242,6 @@ void ElfWriterQuick<ElfTypes>::EndDataBimgRelRo(OutputStream* data_bimg_rel_ro)
 
 template <typename ElfTypes>
 void ElfWriterQuick<ElfTypes>::WriteDynamicSection() {
-  if (builder_->GetIsa() == InstructionSet::kMips ||
-      builder_->GetIsa() == InstructionSet::kMips64) {
-    builder_->WriteMIPSabiflagsSection();
-  }
   builder_->WriteDynamicSection();
 }
 
diff --git a/dex2oat/linker/elf_writer_test.cc b/dex2oat/linker/elf_writer_test.cc
index d8a360add2..c1ff8f2988 100644
--- a/dex2oat/linker/elf_writer_test.cc
+++ b/dex2oat/linker/elf_writer_test.cc
@@ -23,10 +23,10 @@
 #include "base/unix_file/fd_file.h"
 #include "base/utils.h"
 #include "common_compiler_driver_test.h"
+#include "elf/elf_builder.h"
 #include "elf_file.h"
 #include "elf_file_impl.h"
 #include "elf_writer_quick.h"
-#include "linker/elf_builder.h"
 #include "oat.h"
 
 namespace art {
diff --git a/dex2oat/linker/image_test.h b/dex2oat/linker/image_test.h
index aa4fb70aba..7209fbfce5 100644
--- a/dex2oat/linker/image_test.h
+++ b/dex2oat/linker/image_test.h
@@ -43,16 +43,16 @@
 #include "driver/compiler_options.h"
 #include "gc/space/image_space.h"
 #include "image_writer.h"
-#include "linker/buffered_output_stream.h"
 #include "linker/elf_writer.h"
 #include "linker/elf_writer_quick.h"
-#include "linker/file_output_stream.h"
 #include "linker/multi_oat_relative_patcher.h"
 #include "lock_word.h"
 #include "mirror/object-inl.h"
 #include "oat_writer.h"
 #include "scoped_thread_state_change-inl.h"
 #include "signal_catcher.h"
+#include "stream/buffered_output_stream.h"
+#include "stream/file_output_stream.h"
 
 namespace art {
 namespace linker {
diff --git a/dex2oat/linker/multi_oat_relative_patcher_test.cc b/dex2oat/linker/multi_oat_relative_patcher_test.cc
index 2610561683..274084f030 100644
--- a/dex2oat/linker/multi_oat_relative_patcher_test.cc
+++ b/dex2oat/linker/multi_oat_relative_patcher_test.cc
@@ -20,7 +20,7 @@
 #include "debug/method_debug_info.h"
 #include "gtest/gtest.h"
 #include "linker/linker_patch.h"
-#include "linker/vector_output_stream.h"
+#include "stream/vector_output_stream.h"
 
 namespace art {
 namespace linker {
diff --git a/dex2oat/linker/oat_writer.cc b/dex2oat/linker/oat_writer.cc
index a6fb2dea41..897278f6c8 100644
--- a/dex2oat/linker/oat_writer.cc
+++ b/dex2oat/linker/oat_writer.cc
@@ -54,12 +54,9 @@
 #include "gc/space/space.h"
 #include "handle_scope-inl.h"
 #include "image_writer.h"
-#include "linker/buffered_output_stream.h"
-#include "linker/file_output_stream.h"
 #include "linker/index_bss_mapping_encoder.h"
 #include "linker/linker_patch.h"
 #include "linker/multi_oat_relative_patcher.h"
-#include "linker/output_stream.h"
 #include "mirror/array.h"
 #include "mirror/class_loader.h"
 #include "mirror/dex_cache-inl.h"
@@ -69,6 +66,9 @@
 #include "quicken_info.h"
 #include "scoped_thread_state_change-inl.h"
 #include "stack_map.h"
+#include "stream/buffered_output_stream.h"
+#include "stream/file_output_stream.h"
+#include "stream/output_stream.h"
 #include "utils/dex_cache_arrays_layout-inl.h"
 #include "vdex_file.h"
 #include "verifier/verifier_deps.h"
diff --git a/dex2oat/linker/oat_writer.h b/dex2oat/linker/oat_writer.h
index 37785f2505..84d13a8522 100644
--- a/dex2oat/linker/oat_writer.h
+++ b/dex2oat/linker/oat_writer.h
@@ -44,6 +44,7 @@ class CompiledMethod;
 class CompilerDriver;
 class CompilerOptions;
 class DexContainer;
+class OutputStream;
 class ProfileCompilationInfo;
 class TimingLogger;
 class TypeLookupTable;
@@ -62,7 +63,6 @@ namespace linker {
 
 class ImageWriter;
 class MultiOatRelativePatcher;
-class OutputStream;
 
 enum class CopyOption {
   kNever,
diff --git a/dex2oat/linker/oat_writer_test.cc b/dex2oat/linker/oat_writer_test.cc
index ae22477ea4..c46aa18703 100644
--- a/dex2oat/linker/oat_writer_test.cc
+++ b/dex2oat/linker/oat_writer_test.cc
@@ -35,12 +35,9 @@
 #include "driver/compiler_driver.h"
 #include "driver/compiler_options.h"
 #include "entrypoints/quick/quick_entrypoints.h"
-#include "linker/buffered_output_stream.h"
 #include "linker/elf_writer.h"
 #include "linker/elf_writer_quick.h"
-#include "linker/file_output_stream.h"
 #include "linker/multi_oat_relative_patcher.h"
-#include "linker/vector_output_stream.h"
 #include "mirror/class-inl.h"
 #include "mirror/object-inl.h"
 #include "mirror/object_array-inl.h"
@@ -48,6 +45,9 @@
 #include "oat_writer.h"
 #include "profile/profile_compilation_info.h"
 #include "scoped_thread_state_change-inl.h"
+#include "stream/buffered_output_stream.h"
+#include "stream/file_output_stream.h"
+#include "stream/vector_output_stream.h"
 #include "vdex_file.h"
 
 namespace art {
diff --git a/dex2oat/linker/relative_patcher.cc b/dex2oat/linker/relative_patcher.cc
index 45a4a226d9..4db0e8a94e 100644
--- a/dex2oat/linker/relative_patcher.cc
+++ b/dex2oat/linker/relative_patcher.cc
@@ -35,7 +35,7 @@
 #ifdef ART_ENABLE_CODEGEN_x86_64
 #include "linker/x86_64/relative_patcher_x86_64.h"
 #endif
-#include "linker/output_stream.h"
+#include "stream/output_stream.h"
 
 namespace art {
 namespace linker {
diff --git a/dex2oat/linker/relative_patcher.h b/dex2oat/linker/relative_patcher.h
index d80eaf94f7..e8e15c9ea8 100644
--- a/dex2oat/linker/relative_patcher.h
+++ b/dex2oat/linker/relative_patcher.h
@@ -28,6 +28,7 @@
 namespace art {
 
 class CompiledMethod;
+class OutputStream;
 
 namespace debug {
 struct MethodDebugInfo;
@@ -36,7 +37,6 @@ struct MethodDebugInfo;
 namespace linker {
 
 class LinkerPatch;
-class OutputStream;
 
 /**
  * @class RelativePatcherThunkProvider
diff --git a/dex2oat/linker/relative_patcher_test.h b/dex2oat/linker/relative_patcher_test.h
index 4329ee1697..dead38d3df 100644
--- a/dex2oat/linker/relative_patcher_test.h
+++ b/dex2oat/linker/relative_patcher_test.h
@@ -29,9 +29,9 @@
 #include "dex/string_reference.h"
 #include "driver/compiled_method_storage.h"
 #include "linker/relative_patcher.h"
-#include "linker/vector_output_stream.h"
 #include "oat.h"
 #include "oat_quick_method_header.h"
+#include "stream/vector_output_stream.h"
 
 namespace art {
 namespace linker {
diff --git a/libelffile/Android.bp b/libelffile/Android.bp
new file mode 100644
index 0000000000..60499dc379
--- /dev/null
+++ b/libelffile/Android.bp
@@ -0,0 +1,55 @@
+//
+// Copyright (C) 2011 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+// Needed to import elf.h in the runtime.
+cc_library_headers {
+    name: "libelffile-headers",
+    host_supported: true,
+    export_include_dirs: ["."],
+}
+
+art_cc_defaults {
+    name: "libelffile-defaults",
+    host_supported: true,
+    export_include_dirs: ["."],
+    srcs: [
+        "elf/xz_utils.cc",
+        "stream/buffered_output_stream.cc",
+        "stream/file_output_stream.cc",
+        "stream/output_stream.cc",
+        "stream/vector_output_stream.cc",
+    ],
+    shared_libs: [
+        "libartbase",
+        "libbase",
+    ],
+}
+
+art_cc_library_static {
+    name: "libelffile",
+    defaults: [
+        "art_defaults",
+        "libelffile-defaults",
+    ],
+}
+
+art_cc_library_static {
+    name: "libelffiled",
+    defaults: [
+        "art_debug_defaults",
+        "libelffile-defaults",
+    ],
+}
diff --git a/compiler/debug/dwarf/debug_abbrev_writer.h b/libelffile/dwarf/debug_abbrev_writer.h
index 63a049b2cc..eecaa0588d 100644
--- a/compiler/debug/dwarf/debug_abbrev_writer.h
+++ b/libelffile/dwarf/debug_abbrev_writer.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_DEBUG_DWARF_DEBUG_ABBREV_WRITER_H_
-#define ART_COMPILER_DEBUG_DWARF_DEBUG_ABBREV_WRITER_H_
+#ifndef ART_LIBELFFILE_DWARF_DEBUG_ABBREV_WRITER_H_
+#define ART_LIBELFFILE_DWARF_DEBUG_ABBREV_WRITER_H_
 
 #include <cstdint>
 #include <type_traits>
@@ -24,8 +24,8 @@
 #include "base/casts.h"
 #include "base/leb128.h"
 #include "base/stl_util.h"
-#include "debug/dwarf/dwarf_constants.h"
-#include "debug/dwarf/writer.h"
+#include "dwarf/dwarf_constants.h"
+#include "dwarf/writer.h"
 
 namespace art {
 namespace dwarf {
@@ -95,4 +95,4 @@ class DebugAbbrevWriter final : private Writer<Vector> {
 }  // namespace dwarf
 }  // namespace art
 
-#endif  // ART_COMPILER_DEBUG_DWARF_DEBUG_ABBREV_WRITER_H_
+#endif  // ART_LIBELFFILE_DWARF_DEBUG_ABBREV_WRITER_H_
diff --git a/compiler/debug/dwarf/debug_frame_opcode_writer.h b/libelffile/dwarf/debug_frame_opcode_writer.h
index 7c75c9bf37..b255f9c1f4 100644
--- a/compiler/debug/dwarf/debug_frame_opcode_writer.h
+++ b/libelffile/dwarf/debug_frame_opcode_writer.h
@@ -14,13 +14,13 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_DEBUG_DWARF_DEBUG_FRAME_OPCODE_WRITER_H_
-#define ART_COMPILER_DEBUG_DWARF_DEBUG_FRAME_OPCODE_WRITER_H_
+#ifndef ART_LIBELFFILE_DWARF_DEBUG_FRAME_OPCODE_WRITER_H_
+#define ART_LIBELFFILE_DWARF_DEBUG_FRAME_OPCODE_WRITER_H_
 
 #include "base/bit_utils.h"
-#include "debug/dwarf/dwarf_constants.h"
-#include "debug/dwarf/register.h"
-#include "debug/dwarf/writer.h"
+#include "dwarf/dwarf_constants.h"
+#include "dwarf/register.h"
+#include "dwarf/writer.h"
 
 namespace art {
 namespace dwarf {
@@ -338,4 +338,4 @@ class DebugFrameOpCodeWriter : private Writer<Vector> {
 }  // namespace dwarf
 }  // namespace art
 
-#endif  // ART_COMPILER_DEBUG_DWARF_DEBUG_FRAME_OPCODE_WRITER_H_
+#endif  // ART_LIBELFFILE_DWARF_DEBUG_FRAME_OPCODE_WRITER_H_
diff --git a/compiler/debug/dwarf/debug_info_entry_writer.h b/libelffile/dwarf/debug_info_entry_writer.h
index b198178d5d..48654e91a6 100644
--- a/compiler/debug/dwarf/debug_info_entry_writer.h
+++ b/libelffile/dwarf/debug_info_entry_writer.h
@@ -14,18 +14,18 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_DEBUG_DWARF_DEBUG_INFO_ENTRY_WRITER_H_
-#define ART_COMPILER_DEBUG_DWARF_DEBUG_INFO_ENTRY_WRITER_H_
+#ifndef ART_LIBELFFILE_DWARF_DEBUG_INFO_ENTRY_WRITER_H_
+#define ART_LIBELFFILE_DWARF_DEBUG_INFO_ENTRY_WRITER_H_
 
 #include <cstdint>
 #include <unordered_map>
 
 #include "base/casts.h"
 #include "base/leb128.h"
-#include "debug/dwarf/debug_abbrev_writer.h"
-#include "debug/dwarf/dwarf_constants.h"
-#include "debug/dwarf/expression.h"
-#include "debug/dwarf/writer.h"
+#include "dwarf/debug_abbrev_writer.h"
+#include "dwarf/dwarf_constants.h"
+#include "dwarf/expression.h"
+#include "dwarf/writer.h"
 
 namespace art {
 namespace dwarf {
@@ -225,4 +225,4 @@ class DebugInfoEntryWriter final : private Writer<Vector> {
 }  // namespace dwarf
 }  // namespace art
 
-#endif  // ART_COMPILER_DEBUG_DWARF_DEBUG_INFO_ENTRY_WRITER_H_
+#endif  // ART_LIBELFFILE_DWARF_DEBUG_INFO_ENTRY_WRITER_H_
diff --git a/compiler/debug/dwarf/debug_line_opcode_writer.h b/libelffile/dwarf/debug_line_opcode_writer.h
index bb4e87ff7e..95b626e0df 100644
--- a/compiler/debug/dwarf/debug_line_opcode_writer.h
+++ b/libelffile/dwarf/debug_line_opcode_writer.h
@@ -14,13 +14,13 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_DEBUG_DWARF_DEBUG_LINE_OPCODE_WRITER_H_
-#define ART_COMPILER_DEBUG_DWARF_DEBUG_LINE_OPCODE_WRITER_H_
+#ifndef ART_LIBELFFILE_DWARF_DEBUG_LINE_OPCODE_WRITER_H_
+#define ART_LIBELFFILE_DWARF_DEBUG_LINE_OPCODE_WRITER_H_
 
 #include <cstdint>
 
-#include "debug/dwarf/dwarf_constants.h"
-#include "debug/dwarf/writer.h"
+#include "dwarf/dwarf_constants.h"
+#include "dwarf/writer.h"
 
 namespace art {
 namespace dwarf {
@@ -258,4 +258,4 @@ class DebugLineOpCodeWriter final : private Writer<Vector> {
 }  // namespace dwarf
 }  // namespace art
 
-#endif  // ART_COMPILER_DEBUG_DWARF_DEBUG_LINE_OPCODE_WRITER_H_
+#endif  // ART_LIBELFFILE_DWARF_DEBUG_LINE_OPCODE_WRITER_H_
diff --git a/compiler/debug/dwarf/dwarf_constants.h b/libelffile/dwarf/dwarf_constants.h
index 7beb1fa7da..d52db3a7cc 100644
--- a/compiler/debug/dwarf/dwarf_constants.h
+++ b/libelffile/dwarf/dwarf_constants.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_DEBUG_DWARF_DWARF_CONSTANTS_H_
-#define ART_COMPILER_DEBUG_DWARF_DWARF_CONSTANTS_H_
+#ifndef ART_LIBELFFILE_DWARF_DWARF_CONSTANTS_H_
+#define ART_LIBELFFILE_DWARF_DWARF_CONSTANTS_H_
 
 namespace art {
 namespace dwarf {
@@ -683,4 +683,4 @@ enum ExceptionHeaderValueApplication : uint8_t {
 }  // namespace dwarf
 }  // namespace art
 
-#endif  // ART_COMPILER_DEBUG_DWARF_DWARF_CONSTANTS_H_
+#endif  // ART_LIBELFFILE_DWARF_DWARF_CONSTANTS_H_
diff --git a/compiler/debug/dwarf/expression.h b/libelffile/dwarf/expression.h
index fafc0462d6..613da886c2 100644
--- a/compiler/debug/dwarf/expression.h
+++ b/libelffile/dwarf/expression.h
@@ -14,14 +14,14 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_DEBUG_DWARF_EXPRESSION_H_
-#define ART_COMPILER_DEBUG_DWARF_EXPRESSION_H_
+#ifndef ART_LIBELFFILE_DWARF_EXPRESSION_H_
+#define ART_LIBELFFILE_DWARF_EXPRESSION_H_
 
 #include <cstddef>
 #include <cstdint>
 
-#include "debug/dwarf/dwarf_constants.h"
-#include "debug/dwarf/writer.h"
+#include "dwarf/dwarf_constants.h"
+#include "dwarf/writer.h"
 
 namespace art {
 namespace dwarf {
@@ -118,4 +118,4 @@ class Expression : private Writer<> {
 }  // namespace dwarf
 }  // namespace art
 
-#endif  // ART_COMPILER_DEBUG_DWARF_EXPRESSION_H_
+#endif  // ART_LIBELFFILE_DWARF_EXPRESSION_H_
diff --git a/compiler/debug/dwarf/headers.h b/libelffile/dwarf/headers.h
index 3cc8ad8290..d77012ffe3 100644
--- a/compiler/debug/dwarf/headers.h
+++ b/libelffile/dwarf/headers.h
@@ -14,18 +14,18 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_DEBUG_DWARF_HEADERS_H_
-#define ART_COMPILER_DEBUG_DWARF_HEADERS_H_
+#ifndef ART_LIBELFFILE_DWARF_HEADERS_H_
+#define ART_LIBELFFILE_DWARF_HEADERS_H_
 
 #include <cstdint>
 
 #include "base/array_ref.h"
-#include "debug/dwarf/debug_frame_opcode_writer.h"
-#include "debug/dwarf/debug_info_entry_writer.h"
-#include "debug/dwarf/debug_line_opcode_writer.h"
-#include "debug/dwarf/dwarf_constants.h"
-#include "debug/dwarf/register.h"
-#include "debug/dwarf/writer.h"
+#include "dwarf/debug_frame_opcode_writer.h"
+#include "dwarf/debug_info_entry_writer.h"
+#include "dwarf/debug_line_opcode_writer.h"
+#include "dwarf/dwarf_constants.h"
+#include "dwarf/register.h"
+#include "dwarf/writer.h"
 
 namespace art {
 namespace dwarf {
@@ -159,4 +159,4 @@ void WriteDebugLineTable(const std::vector<std::string>& include_directories,
 }  // namespace dwarf
 }  // namespace art
 
-#endif  // ART_COMPILER_DEBUG_DWARF_HEADERS_H_
+#endif  // ART_LIBELFFILE_DWARF_HEADERS_H_
diff --git a/compiler/debug/dwarf/register.h b/libelffile/dwarf/register.h
index 24bacac292..eadb441f15 100644
--- a/compiler/debug/dwarf/register.h
+++ b/libelffile/dwarf/register.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_DEBUG_DWARF_REGISTER_H_
-#define ART_COMPILER_DEBUG_DWARF_REGISTER_H_
+#ifndef ART_LIBELFFILE_DWARF_REGISTER_H_
+#define ART_LIBELFFILE_DWARF_REGISTER_H_
 
 namespace art {
 namespace dwarf {
@@ -59,4 +59,4 @@ class Reg {
 }  // namespace dwarf
 }  // namespace art
 
-#endif  // ART_COMPILER_DEBUG_DWARF_REGISTER_H_
+#endif  // ART_LIBELFFILE_DWARF_REGISTER_H_
diff --git a/compiler/debug/dwarf/writer.h b/libelffile/dwarf/writer.h
index c09d97aa79..a9764f6c1f 100644
--- a/compiler/debug/dwarf/writer.h
+++ b/libelffile/dwarf/writer.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_DEBUG_DWARF_WRITER_H_
-#define ART_COMPILER_DEBUG_DWARF_WRITER_H_
+#ifndef ART_LIBELFFILE_DWARF_WRITER_H_
+#define ART_LIBELFFILE_DWARF_WRITER_H_
 
 #include <type_traits>
 #include <vector>
@@ -181,4 +181,4 @@ class Writer {
 }  // namespace dwarf
 }  // namespace art
 
-#endif  // ART_COMPILER_DEBUG_DWARF_WRITER_H_
+#endif  // ART_LIBELFFILE_DWARF_WRITER_H_
diff --git a/runtime/CPPLINT.cfg b/libelffile/elf/CPPLINT.cfg
index 6f274994a9..6f274994a9 100644
--- a/runtime/CPPLINT.cfg
+++ b/libelffile/elf/CPPLINT.cfg
diff --git a/runtime/elf.h b/libelffile/elf/elf.h
index 521d4a232f..8eb9ae2dcb 100644
--- a/runtime/elf.h
+++ b/libelffile/elf/elf.h
@@ -18,8 +18,11 @@
 //===----------------------------------------------------------------------===//
 
 // BEGIN android-changed
-#ifndef ART_RUNTIME_ELF_H_
-#define ART_RUNTIME_ELF_H_
+#ifndef ART_LIBELFFILE_ELF_ELF_H_
+#define ART_LIBELFFILE_ELF_ELF_H_
+// HACK: This file replaces the system elf.h header and defines everything needed.
+//   Avoid including the system header as that would lead to re-definition errors.
+#define _ELF_H
 // END android-changed
 
 // BEGIN android-changed
@@ -1892,5 +1895,5 @@ struct ElfTypes64 {
 };
 
 // BEGIN android-changed
-#endif  // ART_RUNTIME_ELF_H_
+#endif  // ART_LIBELFFILE_ELF_ELF_H_
 // END android-changed
diff --git a/compiler/linker/elf_builder.h b/libelffile/elf/elf_builder.h
index 33e1866c50..1f6781a37b 100644
--- a/compiler/linker/elf_builder.h
+++ b/libelffile/elf/elf_builder.h
@@ -14,24 +14,22 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_LINKER_ELF_BUILDER_H_
-#define ART_COMPILER_LINKER_ELF_BUILDER_H_
+#ifndef ART_LIBELFFILE_ELF_ELF_BUILDER_H_
+#define ART_LIBELFFILE_ELF_ELF_BUILDER_H_
 
 #include <vector>
 #include <deque>
 
 #include "arch/instruction_set.h"
-#include "arch/mips/instruction_set_features_mips.h"
 #include "base/array_ref.h"
 #include "base/bit_utils.h"
 #include "base/casts.h"
 #include "base/leb128.h"
 #include "base/unix_file/fd_file.h"
-#include "elf_utils.h"
-#include "linker/error_delaying_output_stream.h"
+#include "elf/elf.h"
+#include "stream/error_delaying_output_stream.h"
 
 namespace art {
-namespace linker {
 
 // Writes ELF file.
 //
@@ -43,7 +41,6 @@ namespace linker {
 //   .text                       - Compiled code.
 //   .bss                        - Zero-initialized writeable section.
 //   .dex                        - Reserved NOBITS space for dex-related data.
-//   .MIPS.abiflags              - MIPS specific section.
 //   .dynstr                     - Names for .dynsym.
 //   .dynsym                     - A few oat-specific dynamic symbols.
 //   .hash                       - Hash-table for .dynsym.
@@ -397,76 +394,6 @@ class ElfBuilder final {
     std::deque<Elf_Sym> syms_;  // Buffered/cached content of the whole section.
   };
 
-  class AbiflagsSection final : public Section {
-   public:
-    // Section with Mips abiflag info.
-    static constexpr uint8_t MIPS_AFL_REG_NONE =         0;  // no registers
-    static constexpr uint8_t MIPS_AFL_REG_32 =           1;  // 32-bit registers
-    static constexpr uint8_t MIPS_AFL_REG_64 =           2;  // 64-bit registers
-    static constexpr uint32_t MIPS_AFL_FLAGS1_ODDSPREG = 1;  // Uses odd single-prec fp regs
-    static constexpr uint8_t MIPS_ABI_FP_DOUBLE =        1;  // -mdouble-float
-    static constexpr uint8_t MIPS_ABI_FP_XX =            5;  // -mfpxx
-    static constexpr uint8_t MIPS_ABI_FP_64A =           7;  // -mips32r* -mfp64 -mno-odd-spreg
-
-    AbiflagsSection(ElfBuilder<ElfTypes>* owner,
-                    const std::string& name,
-                    Elf_Word type,
-                    Elf_Word flags,
-                    const Section* link,
-                    Elf_Word info,
-                    Elf_Word align,
-                    Elf_Word entsize,
-                    InstructionSet isa,
-                    const InstructionSetFeatures* features)
-        : Section(owner, name, type, flags, link, info, align, entsize) {
-      if (isa == InstructionSet::kMips || isa == InstructionSet::kMips64) {
-        bool fpu32 = false;    // assume mips64 values
-        uint8_t isa_rev = 6;   // assume mips64 values
-        if (isa == InstructionSet::kMips) {
-          // adjust for mips32 values
-          fpu32 = features->AsMipsInstructionSetFeatures()->Is32BitFloatingPoint();
-          isa_rev = features->AsMipsInstructionSetFeatures()->IsR6()
-              ? 6
-              : features->AsMipsInstructionSetFeatures()->IsMipsIsaRevGreaterThanEqual2()
-                  ? (fpu32 ? 2 : 5)
-                  : 1;
-        }
-        abiflags_.version = 0;  // version of flags structure
-        abiflags_.isa_level = (isa == InstructionSet::kMips) ? 32 : 64;
-        abiflags_.isa_rev = isa_rev;
-        abiflags_.gpr_size = (isa == InstructionSet::kMips) ? MIPS_AFL_REG_32 : MIPS_AFL_REG_64;
-        abiflags_.cpr1_size = fpu32 ? MIPS_AFL_REG_32 : MIPS_AFL_REG_64;
-        abiflags_.cpr2_size = MIPS_AFL_REG_NONE;
-        // Set the fp_abi to MIPS_ABI_FP_64A for mips32 with 64-bit FPUs (ie: mips32 R5 and R6).
-        // Otherwise set to MIPS_ABI_FP_DOUBLE.
-        abiflags_.fp_abi =
-            (isa == InstructionSet::kMips && !fpu32) ? MIPS_ABI_FP_64A : MIPS_ABI_FP_DOUBLE;
-        abiflags_.isa_ext = 0;
-        abiflags_.ases = 0;
-        // To keep the code simple, we are not using odd FP reg for single floats for both
-        // mips32 and mips64 ART. Therefore we are not setting the MIPS_AFL_FLAGS1_ODDSPREG bit.
-        abiflags_.flags1 = 0;
-        abiflags_.flags2 = 0;
-      }
-    }
-
-    Elf_Word GetSize() const {
-      return sizeof(abiflags_);
-    }
-
-    void Write() {
-      this->WriteFully(&abiflags_, sizeof(abiflags_));
-    }
-
-   private:
-    struct {
-      uint16_t version;  // version of this structure
-      uint8_t  isa_level, isa_rev, gpr_size, cpr1_size, cpr2_size;
-      uint8_t  fp_abi;
-      uint32_t isa_ext, ases, flags1, flags2;
-    } abiflags_;
-  };
-
   class BuildIdSection final : public Section {
    public:
     BuildIdSection(ElfBuilder<ElfTypes>* owner,
@@ -515,9 +442,8 @@ class ElfBuilder final {
     off_t digest_start_;
   };
 
-  ElfBuilder(InstructionSet isa, const InstructionSetFeatures* features, OutputStream* output)
+  ElfBuilder(InstructionSet isa, OutputStream* output)
       : isa_(isa),
-        features_(features),
         stream_(output),
         rodata_(this, ".rodata", SHT_PROGBITS, SHF_ALLOC, nullptr, 0, kPageSize, 0),
         text_(this, ".text", SHT_PROGBITS, SHF_ALLOC | SHF_EXECINSTR, nullptr, 0, kPageSize, 0),
@@ -537,8 +463,6 @@ class ElfBuilder final {
         debug_info_(this, ".debug_info", SHT_PROGBITS, 0, nullptr, 0, 1, 0),
         debug_line_(this, ".debug_line", SHT_PROGBITS, 0, nullptr, 0, 1, 0),
         shstrtab_(this, ".shstrtab", 0, 1),
-        abiflags_(this, ".MIPS.abiflags", SHT_MIPS_ABIFLAGS, SHF_ALLOC, nullptr, 0, kPageSize, 0,
-                  isa, features),
         build_id_(this, ".note.gnu.build-id", SHT_NOTE, SHF_ALLOC, nullptr, 0, 4, 0),
         current_section_(nullptr),
         started_(false),
@@ -552,7 +476,6 @@ class ElfBuilder final {
     dex_.phdr_flags_ = PF_R;
     dynamic_.phdr_flags_ = PF_R | PF_W;
     dynamic_.phdr_type_ = PT_DYNAMIC;
-    abiflags_.phdr_type_ = PT_MIPS_ABIFLAGS;
     build_id_.phdr_type_ = PT_NOTE;
   }
   ~ElfBuilder() {}
@@ -637,7 +560,7 @@ class ElfBuilder final {
     stream_.Flush();
 
     // The main ELF header.
-    Elf_Ehdr elf_header = MakeElfHeader(isa_, features_);
+    Elf_Ehdr elf_header = MakeElfHeader(isa_);
     elf_header.e_shoff = section_headers_offset;
     elf_header.e_shnum = shdrs.size();
     elf_header.e_shstrndx = shstrtab_.GetSectionIndex();
@@ -722,9 +645,6 @@ class ElfBuilder final {
     if (dex_size != 0) {
       dex_.AllocateVirtualMemory(dex_size);
     }
-    if (isa_ == InstructionSet::kMips || isa_ == InstructionSet::kMips64) {
-      abiflags_.AllocateVirtualMemory(abiflags_.GetSize());
-    }
 
     // Cache .dynstr, .dynsym and .hash data.
     dynstr_.Add("");  // dynstr should start with empty string.
@@ -847,12 +767,6 @@ class ElfBuilder final {
     return loaded_size_;
   }
 
-  void WriteMIPSabiflagsSection() {
-    abiflags_.Start();
-    abiflags_.Write();
-    abiflags_.End();
-  }
-
   void WriteBuildIdSection() {
     build_id_.Start();
     build_id_.Write();
@@ -880,7 +794,7 @@ class ElfBuilder final {
   }
 
  private:
-  static Elf_Ehdr MakeElfHeader(InstructionSet isa, const InstructionSetFeatures* features) {
+  static Elf_Ehdr MakeElfHeader(InstructionSet isa) {
     Elf_Ehdr elf_header = Elf_Ehdr();
     switch (isa) {
       case InstructionSet::kArm:
@@ -905,25 +819,6 @@ class ElfBuilder final {
         elf_header.e_flags = 0;
         break;
       }
-      case InstructionSet::kMips: {
-        elf_header.e_machine = EM_MIPS;
-        elf_header.e_flags = (EF_MIPS_NOREORDER |
-                              EF_MIPS_PIC       |
-                              EF_MIPS_CPIC      |
-                              EF_MIPS_ABI_O32   |
-                              (features->AsMipsInstructionSetFeatures()->IsR6()
-                                   ? EF_MIPS_ARCH_32R6
-                                   : EF_MIPS_ARCH_32R2));
-        break;
-      }
-      case InstructionSet::kMips64: {
-        elf_header.e_machine = EM_MIPS;
-        elf_header.e_flags = (EF_MIPS_NOREORDER |
-                              EF_MIPS_PIC       |
-                              EF_MIPS_CPIC      |
-                              EF_MIPS_ARCH_64R6);
-        break;
-      }
       case InstructionSet::kNone: {
         LOG(FATAL) << "No instruction set";
         break;
@@ -1032,7 +927,6 @@ class ElfBuilder final {
   }
 
   InstructionSet isa_;
-  const InstructionSetFeatures* features_;
 
   ErrorDelayingOutputStream stream_;
 
@@ -1052,7 +946,6 @@ class ElfBuilder final {
   Section debug_info_;
   Section debug_line_;
   StringSection shstrtab_;
-  AbiflagsSection abiflags_;
   BuildIdSection build_id_;
   std::vector<std::unique_ptr<Section>> other_sections_;
 
@@ -1073,7 +966,6 @@ class ElfBuilder final {
   DISALLOW_COPY_AND_ASSIGN(ElfBuilder);
 };
 
-}  // namespace linker
 }  // namespace art
 
-#endif  // ART_COMPILER_LINKER_ELF_BUILDER_H_
+#endif  // ART_LIBELFFILE_ELF_ELF_BUILDER_H_
diff --git a/compiler/debug/elf_debug_reader.h b/libelffile/elf/elf_debug_reader.h
index 1820e7cdc7..3b3c050f53 100644
--- a/compiler/debug/elf_debug_reader.h
+++ b/libelffile/elf/elf_debug_reader.h
@@ -14,19 +14,18 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_DEBUG_ELF_DEBUG_READER_H_
-#define ART_COMPILER_DEBUG_ELF_DEBUG_READER_H_
+#ifndef ART_LIBELFFILE_ELF_ELF_DEBUG_READER_H_
+#define ART_LIBELFFILE_ELF_ELF_DEBUG_READER_H_
 
 #include "base/array_ref.h"
-#include "debug/dwarf/headers.h"
-#include "elf.h"
+#include "dwarf/headers.h"
+#include "elf/elf.h"
 #include "xz_utils.h"
 
 #include <map>
 #include <string_view>
 
 namespace art {
-namespace debug {
 
 // Trivial ELF file reader.
 //
@@ -168,6 +167,5 @@ class ElfDebugReader {
   DISALLOW_COPY_AND_ASSIGN(ElfDebugReader);
 };
 
-}  // namespace debug
 }  // namespace art
-#endif  // ART_COMPILER_DEBUG_ELF_DEBUG_READER_H_
+#endif  // ART_LIBELFFILE_ELF_ELF_DEBUG_READER_H_
diff --git a/compiler/debug/xz_utils.cc b/libelffile/elf/xz_utils.cc
index 5b36209d2f..0d47171258 100644
--- a/compiler/debug/xz_utils.cc
+++ b/libelffile/elf/xz_utils.cc
@@ -31,7 +31,6 @@
 #include "XzEnc.h"
 
 namespace art {
-namespace debug {
 
 constexpr size_t kChunkSize = kPageSize;
 
@@ -130,5 +129,4 @@ void XzDecompress(ArrayRef<const uint8_t> src, std::vector<uint8_t>* dst) {
   dst->resize(dst_offset);
 }
 
-}  // namespace debug
 }  // namespace art
diff --git a/compiler/debug/xz_utils.h b/libelffile/elf/xz_utils.h
index 731b03c7e1..2b11584ef0 100644
--- a/compiler/debug/xz_utils.h
+++ b/libelffile/elf/xz_utils.h
@@ -14,20 +14,18 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_DEBUG_XZ_UTILS_H_
-#define ART_COMPILER_DEBUG_XZ_UTILS_H_
+#ifndef ART_LIBELFFILE_ELF_XZ_UTILS_H_
+#define ART_LIBELFFILE_ELF_XZ_UTILS_H_
 
 #include <vector>
 
 #include "base/array_ref.h"
 
 namespace art {
-namespace debug {
 
 void XzCompress(ArrayRef<const uint8_t> src, std::vector<uint8_t>* dst);
 void XzDecompress(ArrayRef<const uint8_t> src, std::vector<uint8_t>* dst);
 
-}  // namespace debug
 }  // namespace art
 
-#endif  // ART_COMPILER_DEBUG_XZ_UTILS_H_
+#endif  // ART_LIBELFFILE_ELF_XZ_UTILS_H_
diff --git a/compiler/linker/buffered_output_stream.cc b/libelffile/stream/buffered_output_stream.cc
index 07066b76ac..4c66c764a9 100644
--- a/compiler/linker/buffered_output_stream.cc
+++ b/libelffile/stream/buffered_output_stream.cc
@@ -19,7 +19,6 @@
 #include <string.h>
 
 namespace art {
-namespace linker {
 
 BufferedOutputStream::BufferedOutputStream(std::unique_ptr<OutputStream> out)
     : OutputStream(out->GetLocation()),  // Before out is moved to out_.
@@ -68,5 +67,4 @@ off_t BufferedOutputStream::Seek(off_t offset, Whence whence) {
   return out_->Seek(offset, whence);
 }
 
-}  // namespace linker
 }  // namespace art
diff --git a/compiler/linker/buffered_output_stream.h b/libelffile/stream/buffered_output_stream.h
index cb1c44ba23..96abb574e4 100644
--- a/compiler/linker/buffered_output_stream.h
+++ b/libelffile/stream/buffered_output_stream.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_LINKER_BUFFERED_OUTPUT_STREAM_H_
-#define ART_COMPILER_LINKER_BUFFERED_OUTPUT_STREAM_H_
+#ifndef ART_LIBELFFILE_STREAM_BUFFERED_OUTPUT_STREAM_H_
+#define ART_LIBELFFILE_STREAM_BUFFERED_OUTPUT_STREAM_H_
 
 #include <memory>
 
@@ -24,7 +24,6 @@
 #include "base/globals.h"
 
 namespace art {
-namespace linker {
 
 class BufferedOutputStream final : public OutputStream {
  public:
@@ -50,7 +49,6 @@ class BufferedOutputStream final : public OutputStream {
   DISALLOW_COPY_AND_ASSIGN(BufferedOutputStream);
 };
 
-}  // namespace linker
 }  // namespace art
 
-#endif  // ART_COMPILER_LINKER_BUFFERED_OUTPUT_STREAM_H_
+#endif  // ART_LIBELFFILE_STREAM_BUFFERED_OUTPUT_STREAM_H_
diff --git a/compiler/linker/error_delaying_output_stream.h b/libelffile/stream/error_delaying_output_stream.h
index cadd71c3f0..b37ff4e24d 100644
--- a/compiler/linker/error_delaying_output_stream.h
+++ b/libelffile/stream/error_delaying_output_stream.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_LINKER_ERROR_DELAYING_OUTPUT_STREAM_H_
-#define ART_COMPILER_LINKER_ERROR_DELAYING_OUTPUT_STREAM_H_
+#ifndef ART_LIBELFFILE_STREAM_ERROR_DELAYING_OUTPUT_STREAM_H_
+#define ART_LIBELFFILE_STREAM_ERROR_DELAYING_OUTPUT_STREAM_H_
 
 #include "output_stream.h"
 
@@ -24,7 +24,6 @@
 #include "base/macros.h"
 
 namespace art {
-namespace linker {
 
 // OutputStream wrapper that delays reporting an error until Flush().
 class ErrorDelayingOutputStream final : public OutputStream {
@@ -99,7 +98,6 @@ class ErrorDelayingOutputStream final : public OutputStream {
   off_t output_offset_;  // Keep track of the current position in the stream.
 };
 
-}  // namespace linker
 }  // namespace art
 
-#endif  // ART_COMPILER_LINKER_ERROR_DELAYING_OUTPUT_STREAM_H_
+#endif  // ART_LIBELFFILE_STREAM_ERROR_DELAYING_OUTPUT_STREAM_H_
diff --git a/compiler/linker/file_output_stream.cc b/libelffile/stream/file_output_stream.cc
index 477846ec65..bbfbdfdca8 100644
--- a/compiler/linker/file_output_stream.cc
+++ b/libelffile/stream/file_output_stream.cc
@@ -22,7 +22,6 @@
 #include "base/unix_file/fd_file.h"
 
 namespace art {
-namespace linker {
 
 FileOutputStream::FileOutputStream(File* file) : OutputStream(file->GetPath()), file_(file) {}
 
@@ -38,5 +37,4 @@ bool FileOutputStream::Flush() {
   return file_->Flush() == 0;
 }
 
-}  // namespace linker
 }  // namespace art
diff --git a/compiler/linker/file_output_stream.h b/libelffile/stream/file_output_stream.h
index 1417132981..e29930fece 100644
--- a/compiler/linker/file_output_stream.h
+++ b/libelffile/stream/file_output_stream.h
@@ -14,15 +14,14 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_LINKER_FILE_OUTPUT_STREAM_H_
-#define ART_COMPILER_LINKER_FILE_OUTPUT_STREAM_H_
+#ifndef ART_LIBELFFILE_STREAM_FILE_OUTPUT_STREAM_H_
+#define ART_LIBELFFILE_STREAM_FILE_OUTPUT_STREAM_H_
 
 #include "base/os.h"
 
 #include "output_stream.h"
 
 namespace art {
-namespace linker {
 
 class FileOutputStream final : public OutputStream {
  public:
@@ -42,7 +41,6 @@ class FileOutputStream final : public OutputStream {
   DISALLOW_COPY_AND_ASSIGN(FileOutputStream);
 };
 
-}  // namespace linker
 }  // namespace art
 
-#endif  // ART_COMPILER_LINKER_FILE_OUTPUT_STREAM_H_
+#endif  // ART_LIBELFFILE_STREAM_FILE_OUTPUT_STREAM_H_
diff --git a/compiler/linker/output_stream.cc b/libelffile/stream/output_stream.cc
index f5a19138a5..a8b64ca1ce 100644
--- a/compiler/linker/output_stream.cc
+++ b/libelffile/stream/output_stream.cc
@@ -17,7 +17,6 @@
 #include "output_stream.h"
 
 namespace art {
-namespace linker {
 
 std::ostream& operator<<(std::ostream& os, const Whence& rhs) {
   switch (rhs) {
@@ -29,5 +28,4 @@ std::ostream& operator<<(std::ostream& os, const Whence& rhs) {
   return os;
 }
 
-}  // namespace linker
 }  // namespace art
diff --git a/compiler/linker/output_stream.h b/libelffile/stream/output_stream.h
index 5310e2fa41..c9fce68416 100644
--- a/compiler/linker/output_stream.h
+++ b/libelffile/stream/output_stream.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_LINKER_OUTPUT_STREAM_H_
-#define ART_COMPILER_LINKER_OUTPUT_STREAM_H_
+#ifndef ART_LIBELFFILE_STREAM_OUTPUT_STREAM_H_
+#define ART_LIBELFFILE_STREAM_OUTPUT_STREAM_H_
 
 #include <ostream>
 #include <string>
@@ -23,7 +23,6 @@
 #include "base/macros.h"
 
 namespace art {
-namespace linker {
 
 enum Whence {
   kSeekSet = SEEK_SET,
@@ -60,7 +59,6 @@ class OutputStream {
   DISALLOW_COPY_AND_ASSIGN(OutputStream);
 };
 
-}  // namespace linker
 }  // namespace art
 
-#endif  // ART_COMPILER_LINKER_OUTPUT_STREAM_H_
+#endif  // ART_LIBELFFILE_STREAM_OUTPUT_STREAM_H_
diff --git a/compiler/linker/vector_output_stream.cc b/libelffile/stream/vector_output_stream.cc
index f2cae5b1d5..f9724c1cee 100644
--- a/compiler/linker/vector_output_stream.cc
+++ b/libelffile/stream/vector_output_stream.cc
@@ -19,7 +19,6 @@
 #include <android-base/logging.h>
 
 namespace art {
-namespace linker {
 
 VectorOutputStream::VectorOutputStream(const std::string& location, std::vector<uint8_t>* vector)
     : OutputStream(location), offset_(vector->size()), vector_(vector) {}
@@ -46,5 +45,4 @@ off_t VectorOutputStream::Seek(off_t offset, Whence whence) {
   return offset_;
 }
 
-}  // namespace linker
 }  // namespace art
diff --git a/compiler/linker/vector_output_stream.h b/libelffile/stream/vector_output_stream.h
index 0d34da6cba..cf7cbb6d8f 100644
--- a/compiler/linker/vector_output_stream.h
+++ b/libelffile/stream/vector_output_stream.h
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#ifndef ART_COMPILER_LINKER_VECTOR_OUTPUT_STREAM_H_
-#define ART_COMPILER_LINKER_VECTOR_OUTPUT_STREAM_H_
+#ifndef ART_LIBELFFILE_STREAM_VECTOR_OUTPUT_STREAM_H_
+#define ART_LIBELFFILE_STREAM_VECTOR_OUTPUT_STREAM_H_
 
 #include "output_stream.h"
 
@@ -24,7 +24,6 @@
 #include <vector>
 
 namespace art {
-namespace linker {
 
 class VectorOutputStream final : public OutputStream {
  public:
@@ -65,7 +64,6 @@ class VectorOutputStream final : public OutputStream {
   DISALLOW_COPY_AND_ASSIGN(VectorOutputStream);
 };
 
-}  // namespace linker
 }  // namespace art
 
-#endif  // ART_COMPILER_LINKER_VECTOR_OUTPUT_STREAM_H_
+#endif  // ART_LIBELFFILE_STREAM_VECTOR_OUTPUT_STREAM_H_
diff --git a/oatdump/oatdump.cc b/oatdump/oatdump.cc
index 26d00941a4..e395985e24 100644
--- a/oatdump/oatdump.cc
+++ b/oatdump/oatdump.cc
@@ -59,18 +59,15 @@
 #include "dex/type_lookup_table.h"
 #include "dexlayout.h"
 #include "disassembler.h"
+#include "elf/elf_builder.h"
 #include "gc/accounting/space_bitmap-inl.h"
 #include "gc/space/image_space.h"
 #include "gc/space/large_object_space.h"
 #include "gc/space/space-inl.h"
 #include "image-inl.h"
 #include "imtable-inl.h"
-#include "subtype_check.h"
 #include "index_bss_mapping.h"
 #include "interpreter/unstarted_runtime.h"
-#include "linker/buffered_output_stream.h"
-#include "linker/elf_builder.h"
-#include "linker/file_output_stream.h"
 #include "mirror/array-inl.h"
 #include "mirror/class-inl.h"
 #include "mirror/dex_cache-inl.h"
@@ -82,6 +79,9 @@
 #include "scoped_thread_state_change-inl.h"
 #include "stack.h"
 #include "stack_map.h"
+#include "stream/buffered_output_stream.h"
+#include "stream/file_output_stream.h"
+#include "subtype_check.h"
 #include "thread_list.h"
 #include "vdex_file.h"
 #include "verifier/method_verifier.h"
@@ -150,10 +150,10 @@ class OatSymbolizer final {
     if (elf_file == nullptr) {
       return false;
     }
-    std::unique_ptr<linker::BufferedOutputStream> output_stream =
-        std::make_unique<linker::BufferedOutputStream>(
-            std::make_unique<linker::FileOutputStream>(elf_file.get()));
-    builder_.reset(new linker::ElfBuilder<ElfTypes>(isa, features.get(), output_stream.get()));
+    std::unique_ptr<BufferedOutputStream> output_stream =
+        std::make_unique<BufferedOutputStream>(
+            std::make_unique<FileOutputStream>(elf_file.get()));
+    builder_.reset(new ElfBuilder<ElfTypes>(isa, output_stream.get()));
 
     builder_->Start();
 
@@ -176,9 +176,6 @@ class OatSymbolizer final {
       text->End();
     }
 
-    if (isa == InstructionSet::kMips || isa == InstructionSet::kMips64) {
-      builder_->WriteMIPSabiflagsSection();
-    }
     builder_->PrepareDynamicSection(elf_file->GetPath(),
                                     rodata_size,
                                     text_size,
@@ -330,7 +327,7 @@ class OatSymbolizer final {
 
  private:
   const OatFile* oat_file_;
-  std::unique_ptr<linker::ElfBuilder<ElfTypes>> builder_;
+  std::unique_ptr<ElfBuilder<ElfTypes>> builder_;
   std::vector<debug::MethodDebugInfo> method_debug_infos_;
   std::unordered_set<uint32_t> seen_offsets_;
   const std::string output_name_;
diff --git a/runtime/Android.bp b/runtime/Android.bp
index ae97907082..595c7afc23 100644
--- a/runtime/Android.bp
+++ b/runtime/Android.bp
@@ -391,6 +391,7 @@ libart_cc_defaults {
         "libicuuc_headers",
         "libnativehelper_header_only",
         "jni_platform_headers",
+        "libelffile-headers",
     ],
     shared_libs: [
         "libartpalette",
@@ -554,7 +555,7 @@ art_cc_library {
     ],
     shared_libs: [
         "libartd",
-	"libartbase-art-gtest",
+        "libartbase-art-gtest",
         "libbase",
         "libbacktrace",
     ],
diff --git a/runtime/elf_file.h b/runtime/elf_file.h
index 8da7e1a29c..e2094bcd59 100644
--- a/runtime/elf_file.h
+++ b/runtime/elf_file.h
@@ -23,7 +23,7 @@
 #include "base/macros.h"
 #include "base/os.h"
 // Explicitly include our own elf.h to avoid Linux and other dependencies.
-#include "./elf.h"
+#include "elf/elf.h"
 
 namespace art {
 
diff --git a/runtime/elf_file_impl.h b/runtime/elf_file_impl.h
index b55b60f2dc..c1899d27f8 100644
--- a/runtime/elf_file_impl.h
+++ b/runtime/elf_file_impl.h
@@ -23,7 +23,7 @@
 #include <vector>
 
 // Explicitly include our own elf.h to avoid Linux and other dependencies.
-#include "./elf.h"
+#include "elf/elf.h"
 #include "base/mem_map.h"
 
 namespace art {
diff --git a/runtime/elf_utils.h b/runtime/elf_utils.h
index 0cac8e8d02..deb081d590 100644
--- a/runtime/elf_utils.h
+++ b/runtime/elf_utils.h
@@ -22,7 +22,7 @@
 #include <android-base/logging.h>
 
 // Explicitly include our own elf.h to avoid Linux and other dependencies.
-#include "./elf.h"
+#include "elf/elf.h"
 
 namespace art {
 
diff --git a/runtime/oat_file.cc b/runtime/oat_file.cc
index 67803b6121..6edf4480a7 100644
--- a/runtime/oat_file.cc
+++ b/runtime/oat_file.cc
@@ -16,6 +16,9 @@
 
 #include "oat_file.h"
 
+// Our elf.h needs to be included before the system one is indirectly included.
+#include "elf/elf.h"
+
 #include <dlfcn.h>
 #ifndef __APPLE__
 #include <link.h>  // for dl_iterate_phdr.