Initial support for emitting unwinding information in perf jitdump.

src/x64/assembler-x64.cc

 // Copyright 2012 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/x64/assembler-x64.h"
 
 #include <cstring>
 
 #if V8_TARGET_ARCH_X64
 
@@ skipping 302 matching lines @@
   DCHECK(pc_ <= reloc_info_writer.pos());  // No overlap.
   // Set up code descriptor.
   desc->buffer = buffer_;
   desc->buffer_size = buffer_size_;
   desc->instr_size = pc_offset();
   DCHECK(desc->instr_size > 0);  // Zero-size code objects upset the system.
   desc->reloc_size =
       static_cast<int>((buffer_ + buffer_size_) - reloc_info_writer.pos());
   desc->origin = this;
   desc->constant_pool_size = 0;
+  desc->unwinding_info_size = 0;
+  desc->unwinding_info = nullptr;
 }
 
 
 void Assembler::Align(int m) {
   DCHECK(base::bits::IsPowerOfTwo32(m));
   int delta = (m - (pc_offset() & (m - 1))) & (m - 1);
   Nop(delta);
 }
 
 
@@ skipping 4234 matching lines @@
 
 bool RelocInfo::IsInConstantPool() {
   return false;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64