Preliminary support for block contexts in hydrogen.

src/full-codegen.cc

Index: src/full-codegen.cc
diff --git a/src/full-codegen.cc b/src/full-codegen.cc
index 6ae927c9018a16a5462f2448f5ae79bdc3e997a1..3c07c683f2b83e8c44e211be6e3f61da04197e05 100644
--- a/src/full-codegen.cc
+++ b/src/full-codegen.cc
@@ -1052,7 +1052,9 @@ void FullCodeGenerator::VisitBlock(Block* stmt) {
 
   Scope* saved_scope = scope();
   // Push a block context when entering a block with block scoped variables.
-  if (stmt->scope() != NULL) {
+  if (stmt->scope() == NULL) {
+    PrepareForBailoutForId(stmt->EntryId(), NO_REGISTERS);
+  } else {
     scope_ = stmt->scope();
     ASSERT(!scope_->is_module_scope());
     { Comment cmnt(masm_, "[ Extend block context");
@@ -1063,17 +1065,17 @@ void FullCodeGenerator::VisitBlock(Block* stmt) {
       // Replace the context stored in the frame.
       StoreToFrameField(StandardFrameConstants::kContextOffset,
                         context_register());
+      PrepareForBailoutForId(stmt->EntryId(), NO_REGISTERS);
     }
     { Comment cmnt(masm_, "[ Declarations");
       VisitDeclarations(scope_->declarations());
+      PrepareForBailoutForId(stmt->DeclsId(), NO_REGISTERS);
     }
   }
 
-  PrepareForBailoutForId(stmt->EntryId(), NO_REGISTERS);
   VisitStatements(stmt->statements());
   scope_ = saved_scope;
   __ bind(nested_block.break_label());
-  PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
 
   // Pop block context if necessary.
   if (stmt->scope() != NULL) {
@@ -1082,6 +1084,7 @@ void FullCodeGenerator::VisitBlock(Block* stmt) {
     StoreToFrameField(StandardFrameConstants::kContextOffset,
                       context_register());
   }
+  PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
 }