Be less aggressive in sharing contexts between scopes so that sibling contexts

runtime/vm/ast_printer.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/ast_printer.h"
 
 #include "vm/handles.h"
 #include "vm/log.h"
 #include "vm/object.h"
 #include "vm/os.h"
 #include "vm/parser.h"
 
 namespace dart {
 
 AstPrinter::AstPrinter() : indent_(0) { }
 
 
 AstPrinter::~AstPrinter() { }
 
 
 void AstPrinter::VisitGenericAstNode(AstNode* node) {
   ISL_Print("(%s ", node->PrettyName());
   node->VisitChildren(this);
   ISL_Print(")");
 }
 
 
 void AstPrinter::VisitSequenceNode(SequenceNode* node) {
   indent_++;
-  ISL_Print("(%s (scope \"%p\")", node->PrettyName(), node->scope());
+  LocalScope* scope = node->scope();
+  ISL_Print("(%s (scope \"%p\"", node->PrettyName(), scope);
+  if (scope != NULL) {
+    ISL_Print(" loop %d", scope->loop_level());
+    if (scope->HasContextLevel()) {
+      ISL_Print(" context %d captures %d",
+                scope->context_level(),
+                scope->num_context_variables());
+    } else {
+      ASSERT(scope->num_context_variables() == 0);
+    }
+  }
+  ISL_Print(")");
   for (int i = 0; i < node->length(); ++i) {
     ISL_Print("\n");
     for (intptr_t p = 0; p < indent_; p++) {
       ISL_Print("  ");
     }
     node->NodeAt(i)->Visit(this);
   }
   ISL_Print(")");
   indent_--;
 }
@@ skipping 506 matching lines @@
   ASSERT(node_sequence != NULL);
   AstPrinter ast_printer;
   const char* function_name =
       parsed_function.function().ToFullyQualifiedCString();
   ISL_Print("Ast for function '%s' {\n", function_name);
   node_sequence->Visit(&ast_printer);
   ISL_Print("}\n");
 }
 
 }  // namespace dart