Speed up access to global variables from eval scopes. Traverse the...

src/scopeinfo.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 32 matching lines @@
   int x = (s != NULL ? s->index() : 0);
   int y = (t != NULL ? t->index() : 0);
   // Consider sorting them according to type as well?
   return x - y;
 }
 
 
 template<class Allocator>
 ScopeInfo<Allocator>::ScopeInfo(Scope* scope)
     : function_name_(Factory::empty_symbol()),
+      calls_eval_(scope->calls_eval()),
       parameters_(scope->num_parameters()),
       stack_slots_(scope->num_stack_slots()),
       context_slots_(scope->num_heap_slots()),
       context_modes_(scope->num_heap_slots()) {
   // Add parameters.
   for (int i = 0; i < scope->num_parameters(); i++) {
     ASSERT(parameters_.length() == i);
     parameters_.Add(scope->parameter(i)->name());
   }
 
@@ skipping 184 matching lines @@
   : function_name_(Factory::empty_symbol()),
     parameters_(4),
     stack_slots_(8),
     context_slots_(8),
     context_modes_(8) {
   if (code == NULL || code->sinfo_size() == 0) return;
 
   Object** p0 = &Memory::Object_at(code->sinfo_start());
   Object** p = p0;
   p = ReadSymbol(p, &function_name_);
+  p = ReadBool(p, &calls_eval_);
   p = ReadList<Allocator>(p, &context_slots_, &context_modes_);
   p = ReadList<Allocator>(p, &parameters_);
   p = ReadList<Allocator>(p, &stack_slots_);
   ASSERT((p - p0) * kPointerSize == code->sinfo_size());
 }
 
 
 static inline Object** WriteInt(Object** p, int x) {
   *p++ = Smi::FromInt(x);
   return p;
 }
 
 
+static inline Object** WriteBool(Object** p, bool b) {
+  *p++ = Smi::FromInt(b ? 1 : 0);
+  return p;
+}
+
+
 static inline Object** WriteSymbol(Object** p, Handle<String> s) {
   *p++ = *s;
   return p;
 }
 
 
 static inline Object** WriteSentinel(Object** p) {
   *p++ = NULL;
   return p;
 }
@@ skipping 19 matching lines @@
   for (int i = 0; i < n; i++) {
     p = WriteSymbol(p, list->at(i));
     p = WriteInt(p, modes->at(i));
   }
   return WriteSentinel(p);
 }
 
 
 template<class Allocator>
 int ScopeInfo<Allocator>::Serialize(Code* code) {
-  // function name, length & sentinel for 3 tables:
-  const int extra_slots = 1 + 2 * 3;
+  // function name, calls eval, length & sentinel for 3 tables:
+  const int extra_slots = 1 + 1 + 2 * 3;
   int size = (extra_slots +
               context_slots_.length() * 2 +
               parameters_.length() +
               stack_slots_.length()) * kPointerSize;
 
   if (code != NULL) {
     CHECK(code->sinfo_size() == size);
     Object** p0 = &Memory::Object_at(code->sinfo_start());
     Object** p = p0;
     p = WriteSymbol(p, function_name_);
+    p = WriteBool(p, calls_eval_);
     p = WriteList(p, &context_slots_, &context_modes_);
     p = WriteList(p, &parameters_);
     p = WriteList(p, &stack_slots_);
     ASSERT((p - p0) * kPointerSize == size);
   }
 
   return size;
 }
 
 
 template<class Allocator>
 void ScopeInfo<Allocator>::IterateScopeInfo(Code* code, ObjectVisitor* v) {
   Object** start = &Memory::Object_at(code->sinfo_start());
   Object** end = &Memory::Object_at(code->sinfo_start() + code->sinfo_size());
   v->VisitPointers(start, end);
 }
 
 
 static Object** ContextEntriesAddr(Code* code) {
   ASSERT(code->sinfo_size() > 0);
-  // +1 for function name:
-  return &Memory::Object_at(code->sinfo_start()) + 1;
+  // +2 for function name and calls eval:
+  return &Memory::Object_at(code->sinfo_start()) + 2;
 }
 
 
 static Object** ParameterEntriesAddr(Code* code) {
   ASSERT(code->sinfo_size() > 0);
   Object** p = ContextEntriesAddr(code);
   int n;  // number of context slots;
   p = ReadInt(p, &n);
   return p + n*2 + 1;  // *2 for pairs, +1 for sentinel
 }
 
 
 static Object** StackSlotEntriesAddr(Code* code) {
   ASSERT(code->sinfo_size() > 0);
   Object** p = ParameterEntriesAddr(code);
   int n;  // number of parameter slots;
   p = ReadInt(p, &n);
   return p + n + 1;  // +1 for sentinel
 }
 
 
 template<class Allocator>
+bool ScopeInfo<Allocator>::CallsEval(Code* code) {
+  if (code->sinfo_size() > 0) {
+    // +1 for function name:
+    Object** p = &Memory::Object_at(code->sinfo_start()) + 1;
+    bool calls_eval;
+    p = ReadBool(p, &calls_eval);
+    return calls_eval;
+  }
+  return true;
+}
+
+
+template<class Allocator>
 int ScopeInfo<Allocator>::NumberOfStackSlots(Code* code) {
   if (code->sinfo_size() > 0) {
     Object** p = StackSlotEntriesAddr(code);
     int n;  // number of stack slots;
     ReadInt(p, &n);
     return n;
   }
   return 0;
 }
 
@@ skipping 164 matching lines @@
   PrintF("}\n");
 }
 #endif  // DEBUG
 
 
 // Make sure the classes get instantiated by the template system.
 template class ScopeInfo<FreeStoreAllocationPolicy>;
 template class ScopeInfo<PreallocatedStorage>;
 
 } }  // namespace v8::internal