Initial support for emitting unwinding information in perf jitdump.

test/cctest/test-code-layout.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/objects.h"
+#include "test/cctest/cctest.h"
+
+using namespace v8::internal;
+
+TEST(CodeLayoutWithoutUnwindingInfo) {
+  CcTest::InitializeVM();
+  HandleScope handle_scope(CcTest::i_isolate());
+
+  // "Hello, World!" in ASCII.
+  byte buffer_array[13] = {0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x2c, 0x20,
+                           0x57, 0x6f, 0x72, 0x6c, 0x64, 0x21};
+
+  byte* buffer = &buffer_array[0];
+  int buffer_size = sizeof(buffer_array);
+
+  CodeDesc code_desc;
+  code_desc.buffer = buffer;
+  code_desc.buffer_size = buffer_size;
+  code_desc.constant_pool_size = 0;
+  code_desc.instr_size = buffer_size;
+  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());
+
+  CHECK(!code->has_unwinding_info());
+  CHECK_EQ(code->instruction_size(), buffer_size);
+  CHECK_EQ(memcmp(code->instruction_start(), buffer, buffer_size), 0);
+  CHECK_EQ(code->instruction_end() - reinterpret_cast<byte*>(*code),
+           Code::kHeaderSize + buffer_size - kHeapObjectTag);
+}
+
+TEST(CodeLayoutWithUnwindingInfo) {
+  CcTest::InitializeVM();
+  HandleScope handle_scope(CcTest::i_isolate());
+
+  // "Hello, World!" in ASCII.
+  byte buffer_array[13] = {0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x2c, 0x20,
+                           0x57, 0x6f, 0x72, 0x6c, 0x64, 0x21};
+
+  // "JavaScript" in ASCII.
+  byte unwinding_info_array[10] = {0x4a, 0x61, 0x76, 0x61, 0x53,
+                                   0x63, 0x72, 0x69, 0x70, 0x74};
+
+  byte* buffer = &buffer_array[0];
+  int buffer_size = sizeof(buffer_array);
+  byte* unwinding_info = &unwinding_info_array[0];
+  int unwinding_info_size = sizeof(unwinding_info_array);
+
+  CodeDesc code_desc;
+  code_desc.buffer = buffer;
+  code_desc.buffer_size = buffer_size;
+  code_desc.constant_pool_size = 0;
+  code_desc.instr_size = buffer_size;
+  code_desc.reloc_size = 0;
+  code_desc.origin = nullptr;
+  code_desc.unwinding_info = unwinding_info;
+  code_desc.unwinding_info_size = unwinding_info_size;
+
+  Handle<Code> code = CcTest::i_isolate()->factory()->NewCode(
+      code_desc, 0, Handle<Object>::null());
+
+  CHECK(code->has_unwinding_info());
+  CHECK_EQ(code->instruction_size(), buffer_size);
+  CHECK_EQ(memcmp(code->instruction_start(), buffer, buffer_size), 0);
+  CHECK(IsAligned(code->GetUnwindingInfoSizeOffset(), 8));
+  CHECK_EQ(code->unwinding_info_size(), unwinding_info_size);
+  CHECK(
+      IsAligned(reinterpret_cast<uintptr_t>(code->unwinding_info_start()), 8));
+  CHECK_EQ(
+      memcmp(code->unwinding_info_start(), unwinding_info, unwinding_info_size),
+      0);
+  CHECK_EQ(code->unwinding_info_end() - reinterpret_cast<byte*>(*code),
+           Code::kHeaderSize + RoundUp(buffer_size, kInt64Size) + kInt64Size +
+               unwinding_info_size - kHeapObjectTag);
+}