[Interpreter] Ensure that block breaks are within the correct context scope.

src/interpreter/bytecode-generator.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/interpreter/bytecode-generator.h"
 
 #include "src/ast/scopes.h"
 #include "src/compiler.h"
 #include "src/interpreter/bytecode-register-allocator.h"
 #include "src/interpreter/control-flow-builders.h"
@@ skipping 404 matching lines @@
 
   // Visit declarations within the function scope.
   VisitDeclarations(scope()->declarations());
 
   // Visit statements in the function body.
   VisitStatements(info()->literal()->body());
 }
 
 
 void BytecodeGenerator::VisitBlock(Block* stmt) {
-  BlockBuilder block_builder(this->builder());
+  // Visit declarations and statements.
+  if (stmt->scope() != nullptr && stmt->scope()->NeedsContext()) {
+    VisitNewLocalBlockContext(stmt->scope());
+    ContextScope scope(this, stmt->scope());
+    VisitBlockDeclarationsAndStatements(stmt);
+  } else {
+    VisitBlockDeclarationsAndStatements(stmt);
+  }
+}
+
+
+void BytecodeGenerator::VisitBlockDeclarationsAndStatements(Block* stmt) {
+  BlockBuilder block_builder(builder());
   ControlScopeForBreakable execution_control(this, stmt, &block_builder);
-
-  if (stmt->scope() == NULL) {
-    // Visit statements in the same scope, no declarations.
-    VisitStatements(stmt->statements());
-  } else {
-    // Visit declarations and statements in a block scope.
-    if (stmt->scope()->NeedsContext()) {
-      VisitNewLocalBlockContext(stmt->scope());
-      ContextScope scope(this, stmt->scope());
-      VisitDeclarations(stmt->scope()->declarations());
-      VisitStatements(stmt->statements());
-    } else {
-      VisitDeclarations(stmt->scope()->declarations());
-      VisitStatements(stmt->statements());
-    }
+  if (stmt->scope() != nullptr) {
+    VisitDeclarations(stmt->scope()->declarations());
   }
+  VisitStatements(stmt->statements());
   if (stmt->labels() != nullptr) block_builder.EndBlock();
 }
 
 
 void BytecodeGenerator::VisitVariableDeclaration(VariableDeclaration* decl) {
   Variable* variable = decl->proxy()->var();
   VariableMode mode = decl->mode();
   // Const and let variables are initialized with the hole so that we can
   // check that they are only assigned once.
   bool hole_init = mode == CONST || mode == CONST_LEGACY || mode == LET;
@@ skipping 1763 matching lines @@
 }
 
 
 int BytecodeGenerator::feedback_index(FeedbackVectorSlot slot) const {
   return info()->feedback_vector()->GetIndex(slot);
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8