Make non-Module generators only context allocate parameters.

src/runtime/runtime-debug.cc

 // Copyright 2014 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/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/compiler.h"
 #include "src/debug/debug-coverage.h"
 #include "src/debug/debug-evaluate.h"
@@ skipping 903 matching lines @@
 
 RUNTIME_FUNCTION(Runtime_GetGeneratorScopeCount) {
   HandleScope scope(isolate);
   DCHECK_EQ(1, args.length());
 
   if (!args[0]->IsJSGeneratorObject()) return Smi::kZero;
 
   // Check arguments.
   CONVERT_ARG_HANDLE_CHECKED(JSGeneratorObject, gen, 0);
 
+  // Only inspect suspended generator scopes.
+  if (!gen->is_suspended()) {
+    return Smi::kZero;
+  }
+
   // Count the visible scopes.
   int n = 0;
   for (ScopeIterator it(isolate, gen); !it.Done(); it.Next()) {
     n++;
   }
 
   return Smi::FromInt(n);
 }
 
 RUNTIME_FUNCTION(Runtime_GetGeneratorScopeDetails) {
   HandleScope scope(isolate);
   DCHECK_EQ(2, args.length());
 
   if (!args[0]->IsJSGeneratorObject()) {
     return isolate->heap()->undefined_value();
   }
 
   // Check arguments.
   CONVERT_ARG_HANDLE_CHECKED(JSGeneratorObject, gen, 0);
   CONVERT_NUMBER_CHECKED(int, index, Int32, args[1]);
 
+  // Only inspect suspended generator scopes.
+  if (!gen->is_suspended()) {
+    return isolate->heap()->undefined_value();
+  }
+
   // Find the requested scope.
   int n = 0;
   ScopeIterator it(isolate, gen);
   for (; !it.Done() && n < index; it.Next()) {
     n++;
   }
   if (it.Done()) {
     return isolate->heap()->undefined_value();
   }
 
@@ skipping 1005 matching lines @@
 RUNTIME_FUNCTION(Runtime_DebugTogglePreciseCoverage) {
   SealHandleScope shs(isolate);
   CONVERT_BOOLEAN_ARG_CHECKED(enable, 0);
   Coverage::SelectMode(isolate, enable ? debug::Coverage::kPreciseCount
                                        : debug::Coverage::kBestEffort);
   return isolate->heap()->undefined_value();
 }
 
 }  // namespace internal
 }  // namespace v8