[interpreter, debugger] support debug breaks via bytecode array copy

src/compiler/bytecode-graph-builder.cc

 // Copyright 2015 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/compiler/bytecode-graph-builder.h"
 
 #include "src/compiler/bytecode-branch-analysis.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/operator-properties.h"
 #include "src/interpreter/bytecodes.h"
@@ skipping 1462 matching lines @@
   MergeControlToLeaveFunction(control);
 }
 
 void BytecodeGraphBuilder::VisitDebugger() {
   FrameStateBeforeAndAfter states(this);
   Node* call =
       NewNode(javascript()->CallRuntime(Runtime::kHandleDebuggerStatement));
   environment()->BindAccumulator(call, &states);
 }
 
+// We cannot create a graph from the debugger copy of the bytecode array.
+#define DEBUG_BREAK(Name, ...) \
+  void BytecodeGraphBuilder::Visit##Name() { CHECK(false); }

[rmcilroy, 2016/02/16 10:46:38]

/s/CHECK(false)/UNREACHABLE()/

[Yang, 2016/02/19 13:09:17]

Done.

+DEBUG_BREAK_BYTECODE_LIST(DEBUG_BREAK);
+#undef DEBUG_BREAK
+
 void BytecodeGraphBuilder::BuildForInPrepare() {
   FrameStateBeforeAndAfter states(this);
   Node* receiver = environment()->LookupAccumulator();
   Node* prepare = NewNode(javascript()->ForInPrepare(), receiver);
   environment()->BindRegistersToProjections(
       bytecode_iterator().GetRegisterOperand(0), prepare, &states);
 }
 
 void BytecodeGraphBuilder::VisitForInPrepare() { BuildForInPrepare(); }
 
@@ skipping 303 matching lines @@
     // Phi does not exist yet, introduce one.
     value = NewPhi(inputs, value, control);
     value->ReplaceInput(inputs - 1, other);
   }
   return value;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8