Ensure integrity of ASCII strings.

src/heap-inl.h

 // Copyright 2012 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 577 matching lines @@
     v->VisitPointers(start, start + old_space_strings_.length());
   }
 }
 
 
 // Verify() is inline to avoid ifdef-s around its calls in release
 // mode.
 void ExternalStringTable::Verify() {
 #ifdef DEBUG
   for (int i = 0; i < new_space_strings_.length(); ++i) {
-    ASSERT(heap_->InNewSpace(new_space_strings_[i]));
-    ASSERT(new_space_strings_[i] != HEAP->raw_unchecked_the_hole_value());
+    Object* obj = Object::cast(new_space_strings_[i]);
+    // TODO(yangguo): check that the object is indeed an external string.
+    ASSERT(heap_->InNewSpace(obj));
+    ASSERT(obj != HEAP->raw_unchecked_the_hole_value());
+    if (obj->IsExternalAsciiString()) {
+      ExternalAsciiString* string = ExternalAsciiString::cast(obj);
+      ASSERT(String::IsAscii(string->GetChars(), string->length()));
+    }
   }
   for (int i = 0; i < old_space_strings_.length(); ++i) {
-    ASSERT(!heap_->InNewSpace(old_space_strings_[i]));
-    ASSERT(old_space_strings_[i] != HEAP->raw_unchecked_the_hole_value());
+    Object* obj = Object::cast(new_space_strings_[i]);
+    // TODO(yangguo): check that the object is indeed an external string.
+    ASSERT(!heap_->InNewSpace(obj));
+    ASSERT(obj != HEAP->raw_unchecked_the_hole_value());
+    if (obj->IsExternalAsciiString()) {
+      ExternalAsciiString* string = ExternalAsciiString::cast(obj);
+      ASSERT(String::IsAscii(string->GetChars(), string->length()));
+    }
   }
 #endif
 }
 
 
 void ExternalStringTable::AddOldString(String* string) {
   ASSERT(string->IsExternalString());
   ASSERT(!heap_->InNewSpace(string));
   old_space_strings_.Add(string);
 }
@@ skipping 170 matching lines @@
 AssertNoAllocation::~AssertNoAllocation() { }
 DisableAssertNoAllocation::DisableAssertNoAllocation() { }
 DisableAssertNoAllocation::~DisableAssertNoAllocation() { }
 
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_INL_H_