[Interpreter] Add for/while/do support to the bytecode generator.

src/interpreter/control-flow-builders.cc

Index: src/interpreter/control-flow-builders.cc
diff --git a/src/interpreter/control-flow-builders.cc b/src/interpreter/control-flow-builders.cc
new file mode 100644
index 0000000000000000000000000000000000000000..dbe2d11abf954591d6f9f5930479717cc59e5170
--- /dev/null
+++ b/src/interpreter/control-flow-builders.cc
@@ -0,0 +1,45 @@
+// 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/interpreter/control-flow-builders.h"
+
+namespace v8 {
+namespace internal {
+namespace interpreter {
+
+
+LoopBuilder::~LoopBuilder() {
+  DCHECK_EQ(continue_sites_.size(), 0);

[rmcilroy, 2015/10/01 12:12:08]

nit - DCHECK(continue_sites_.empty());

[oth, 2015/10/01 13:13:56]

Done.

+  DCHECK_EQ(break_sites_.size(), 0);
+}
+
+
+void LoopBuilder::SetContinueTarget(const BytecodeLabel* const target) {
+  BindLabels(target, &continue_sites_);
+}
+
+
+void LoopBuilder::SetBreakTarget(const BytecodeLabel* const target) {
+  BindLabels(target, &break_sites_);
+}
+
+
+void LoopBuilder::EmitJump(ZoneVector<BytecodeLabel>* sites) {
+  sites->push_back(BytecodeLabel());
+  builder()->Jump(&sites->back());
+}
+
+
+void LoopBuilder::BindLabels(const BytecodeLabel* const target,
+                             ZoneVector<BytecodeLabel>* labels) {
+  for (size_t i = 0; i < labels->size(); i++) {
+    BytecodeLabel& unbound = labels->at(i);
+    builder()->Bind(&unbound, target);
+  }
+  labels->resize(0);

[rmcilroy, 2015/10/01 12:12:07]

nit - labels->clear() ?

[oth, 2015/10/01 13:13:56]

Done.

+}
+
+}  // namespace interpreter
+}  // namespace internal
+}  // namespace v8