Early draft of strict mode

src/scopes.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
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 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
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@@ skipping 394 matching lines @@
 
 int Scope::ContextChainLength(Scope* scope) {
   int n = 0;
   for (Scope* s = this; s != scope; s = s->outer_scope_) {
     ASSERT(s != NULL);  // scope must be in the scope chain
     if (s->num_heap_slots() > 0) n++;
   }
   return n;
 }
 
+bool Scope::HasDuplicateParameterName() {
+  int length = params_.length();
+  HashMap map(Match, &HashMap::DefaultAllocator, length * 2);

[Lasse Reichstein, 2011/01/13 07:18:40]

If the length is short (e.g., five or less), just do the quadratic comparison.
We are comparing symbols, so it's pretty quick, and I'm guessing that the
average number of arguments to a function is around two (could be a fun thing to
check :).

[Martin Maly, 2011/01/14 00:06:28]

Done.

[Lasse Reichstein, 2011/01/14 11:42:05]

And thinking more about it, just do the simple thing in all cases.

[Martin Maly, 2011/01/14 16:30:43]

Done.

+  for (int i = 0; i < length; i ++) {
+    Handle<String> name = params_[i]->name();
+    HashMap::Entry* p = map.Lookup(name.location(), name->Hash(), true);
+    if (p->value == NULL) {
+      p->value = name.location();
+    } else {
+      // Duplicate found!
+      return true;
+    }
+  }
+  return false;
+}
+
+bool Scope::HasEvalOrArgumentsParameter() {
+  for (int i = 0, length = params_.length(); i < length; i++) {
+    Handle<String> name = params_[i]->name();
+    if (name.is_identical_to(Factory::arguments_symbol()) ||
+        name.is_identical_to(Factory::eval_symbol()))
+      return true;
+  }
+  return false;
+}
 
 #ifdef DEBUG
 static const char* Header(Scope::Type type) {
   switch (type) {
     case Scope::EVAL_SCOPE: return "eval";
     case Scope::FUNCTION_SCOPE: return "function";
     case Scope::GLOBAL_SCOPE: return "global";
   }
   UNREACHABLE();
   return NULL;
@@ skipping 548 matching lines @@
   if (num_heap_slots_ == Context::MIN_CONTEXT_SLOTS &&
       !must_have_local_context) {
     num_heap_slots_ = 0;
   }
 
   // Allocation done.
   ASSERT(num_heap_slots_ == 0 || num_heap_slots_ >= Context::MIN_CONTEXT_SLOTS);
 }
 
 } }  // namespace v8::internal