Reland Implement .eh_frame writer and disassembler.

test/cctest/test-eh-frame-hdr.cc

-// Copyright 2016 the V8 project authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "src/eh-frame.h"
-#include "src/objects.h"
-#include "test/cctest/cctest.h"
-
-using namespace v8::internal;
-
-TEST(EhFrameHdr) {
-  CcTest::InitializeVM();
-  HandleScope handle_scope(CcTest::i_isolate());
-
-  // The content is not relevant in this test
-  byte buffer[10] = {0};
-  byte unwinding_info[30 + EhFrameHdr::kRecordSize] = {0};
-
-  CodeDesc code_desc;
-  code_desc.buffer = &buffer[0];
-  code_desc.buffer_size = sizeof(buffer);
-  code_desc.constant_pool_size = 0;
-  code_desc.instr_size = sizeof(buffer);
-  code_desc.reloc_size = 0;
-  code_desc.origin = nullptr;
-  code_desc.unwinding_info = &unwinding_info[0];
-  code_desc.unwinding_info_size = sizeof(unwinding_info);
-
-  Handle<Code> code = CcTest::i_isolate()->factory()->NewCode(
-      code_desc, 0, Handle<Object>::null());
-
-  EhFrameHdr eh_frame_hdr(*code);
-  CHECK_EQ(eh_frame_hdr.lut_entries_number(), 1);
-
-  //
-  // Plugging some numbers in the DSO layout shown in eh-frame.cc:
-  //
-  //  |      ...      |
-  //  +---------------+ <-- (E) --------
-  //  |               |                ^
-  //  |  Instructions |  10 bytes      | .text
-  //  |               |                v
-  //  +---------------+ <---------------
-  //  |///////////////|
-  //  |////Padding////|   6 bytes
-  //  |///////////////|
-  //  +---------------+ <---(D)---------
-  //  |               |                ^
-  //  |      CIE      |   N bytes*     |
-  //  |               |                |
-  //  +---------------+ <-- (C)        | .eh_frame
-  //  |               |                |
-  //  |      FDE      |  30 - N bytes  |
-  //  |               |                v
-  //  +---------------+ <-- (B) --------
-  //  |    version    |                ^
-  //  +---------------+   4 bytes      |
-  //  |   encoding    |                |
-  //  |  specifiers   |                |
-  //  +---------------+ <---(A)        | .eh_frame_hdr
-  //  |   offset to   |                |
-  //  |   .eh_frame   |                |
-  //  +---------------+                |
-  //  |      ...      |               ...
-  //
-  //  (*) the size of the CIE is platform dependent.
-  //
-  CHECK_EQ(eh_frame_hdr.offset_to_eh_frame(), -(4 + 30));        // A -> D
-  CHECK_EQ(eh_frame_hdr.offset_to_procedure(), -(30 + 6 + 10));  // B -> E
-  CHECK_EQ(eh_frame_hdr.offset_to_fde(),
-           -(30 - EhFrameHdr::kCIESize));  // B -> C
-}
-
-TEST(DummyEhFrameHdr) {
-  CcTest::InitializeVM();
-  HandleScope handle_scope(CcTest::i_isolate());
-
-  byte buffer[10] = {0};  // The content is not relevant in this test
-
-  CodeDesc code_desc;
-  code_desc.buffer = &buffer[0];
-  code_desc.buffer_size = sizeof(buffer);
-  code_desc.constant_pool_size = 0;
-  code_desc.instr_size = sizeof(buffer);
-  code_desc.reloc_size = 0;
-  code_desc.origin = nullptr;
-  code_desc.unwinding_info = nullptr;
-  code_desc.unwinding_info_size = 0;
-
-  Handle<Code> code = CcTest::i_isolate()->factory()->NewCode(
-      code_desc, 0, Handle<Object>::null());
-
-  EhFrameHdr eh_frame_hdr(*code);
-  // A dummy header has an empty LUT
-  CHECK_EQ(eh_frame_hdr.lut_entries_number(), 0);
-  // These values should be irrelevant, but check that they have been zeroed.
-  CHECK_EQ(eh_frame_hdr.offset_to_eh_frame(), 0);
-  CHECK_EQ(eh_frame_hdr.offset_to_procedure(), 0);
-  CHECK_EQ(eh_frame_hdr.offset_to_fde(), 0);
-}