Stack-allocate block variables

src/full-codegen.h

Index: src/full-codegen.h
diff --git a/src/full-codegen.h b/src/full-codegen.h
index 1439942db8ae33785ce817ba91d3c669e34cddf9..ed409b695fcc05457cb9c06e48725e5d7379fad3 100644
--- a/src/full-codegen.h
+++ b/src/full-codegen.h
@@ -16,6 +16,7 @@
 #include "src/compiler.h"
 #include "src/globals.h"
 #include "src/objects.h"
+#include "src/scopes.h"
 
 namespace v8 {
 namespace internal {
@@ -216,9 +217,13 @@ class FullCodeGenerator: public AstVisitor {
     virtual ~NestedBlock() {}
 
     virtual NestedStatement* Exit(int* stack_depth, int* context_length) {
-      if (statement()->AsBlock()->scope() != NULL) {
+      Scope* block_scope = statement()->AsBlock()->scope();
+      if (block_scope != nullptr && block_scope->ContextLocalCount() > 0) {
         ++(*context_length);
       }
+      if (block_scope != nullptr) {
+        *stack_depth += block_scope->num_stack_slots();
+      }
       return previous_;
     }
   };
@@ -906,11 +911,15 @@ class FullCodeGenerator: public AstVisitor {
     MacroAssembler* masm() const { return codegen_->masm(); }
 
     FullCodeGenerator* codegen_;
-    Scope* scope_;
     Scope* saved_scope_;
     BailoutId exit_id_;
+    bool needs_block_context_;
+    bool num_stack_slots_;
   };
 
+  void AllocateLocals(int local_count);
+  void DeallocateLocals(int local_count);
+
   MacroAssembler* masm_;
   CompilationInfo* info_;
   Scope* scope_;