Reland "Implement Math.random() purely in JavaScript" plus fixes.

src/bootstrapper.cc

 // 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 1291 matching lines @@
     native_context()->set_call_as_constructor_delegate(*delegate);
     delegate->shared()->DontAdaptArguments();
   }
 
   // Initialize the out of memory slot.
   native_context()->set_out_of_memory(heap->false_value());
 
   // Initialize the embedder data slot.
   Handle<FixedArray> embedder_data = factory->NewFixedArray(2);
   native_context()->set_embedder_data(*embedder_data);
-
-  // Allocate the random seed slot.
-  Handle<ByteArray> random_seed = factory->NewByteArray(kRandomStateSize);
-  native_context()->set_random_seed(*random_seed);
 }
 
 
 Handle<JSFunction> Genesis::InstallTypedArray(
     const char* name, ElementsKind elementsKind) {
   Handle<JSObject> global = Handle<JSObject>(native_context()->global_object());
   Handle<JSFunction> result = InstallFunction(global, name, JS_TYPED_ARRAY_TYPE,
       JSTypedArray::kSize, isolate()->initial_object_prototype(),
       Builtins::kIllegal, false, true);
 
@@ skipping 1303 matching lines @@
     MakeFunctionInstancePrototypeWritable();
 
     if (!ConfigureGlobalObjects(global_template)) return;
     isolate->counters()->contexts_created_from_scratch()->Increment();
   }
 
   // Initialize experimental globals and install experimental natives.
   InitializeExperimentalGlobal();
   if (!InstallExperimentalNatives()) return;
 
+  // We can't (de-)serialize typed arrays currently, but we are lucky: The state
+  // of the random number generator needs no initialization during snapshot
+  // creation time and we don't need trigonometric functions then.
   if (!Serializer::enabled()) {
+    // Initially seed the per-context random number generator using the
+    // per-isolate random number generator.
+    const int num_elems = 2;
+    const int num_bytes = num_elems * sizeof(uint32_t);
+    uint32_t* state = reinterpret_cast<uint32_t*>(malloc(num_bytes));
+
+    do {
+      isolate->random_number_generator()->NextBytes(state, num_bytes);
+    } while (state[0] == 0 || state[1] == 0);
+
+    v8::Local<v8::ArrayBuffer> buffer = v8::ArrayBuffer::New(state, num_bytes);
+    Utils::OpenHandle(*buffer)->set_should_be_freed(true);
+    v8::Local<v8::Uint32Array> ta = v8::Uint32Array::New(buffer, 0, num_elems);
     Handle<JSBuiltinsObject> builtins(native_context()->builtins());
+    ForceSetProperty(builtins,
+                     factory()->InternalizeOneByteString(
+                         STATIC_ASCII_VECTOR("rngstate")),
+                     Utils::OpenHandle(*ta),
+                     NONE);
+
     // Initialize trigonometric lookup tables and constants.
-    // The snapshot cannot contain typed arrays, and we don't need it to.
     const int table_num_bytes = TrigonometricLookupTable::table_num_bytes();
     v8::Local<v8::ArrayBuffer> sin_buffer = v8::ArrayBuffer::New(
         TrigonometricLookupTable::sin_table(), table_num_bytes);
     v8::Local<v8::ArrayBuffer> cos_buffer = v8::ArrayBuffer::New(
         TrigonometricLookupTable::cos_x_interval_table(), table_num_bytes);
     v8::Local<v8::Float64Array> sin_table = v8::Float64Array::New(
         sin_buffer, 0, TrigonometricLookupTable::table_size());
     v8::Local<v8::Float64Array> cos_table = v8::Float64Array::New(
         cos_buffer, 0, TrigonometricLookupTable::table_size());
 
@@ skipping 14 matching lines @@
                          TrigonometricLookupTable::samples()),
                      NONE);
     ForceSetProperty(builtins,
                      factory()->InternalizeOneByteString(
                          STATIC_ASCII_VECTOR("kIndexConvert")),
                      factory()->NewHeapNumber(
                          TrigonometricLookupTable::samples_over_pi_half()),
                      NONE);
   }
 
-  // Initially seed the per-context random number generator
-  // using the per-isolate random number generator.
-  uint32_t* state = reinterpret_cast<uint32_t*>(
-      native_context()->random_seed()->GetDataStartAddress());
-  do {
-    isolate->random_number_generator()->NextBytes(state, kRandomStateSize);
-  } while (state[0] == 0 || state[1] == 0);
-
   result_ = native_context();
 }
 
 
 // Support for thread preemption.
 
 // Reserve space for statics needing saving and restoring.
 int Bootstrapper::ArchiveSpacePerThread() {
   return sizeof(NestingCounterType);
 }
@@ skipping 13 matching lines @@
   return from + sizeof(NestingCounterType);
 }
 
 
 // Called when the top-level V8 mutex is destroyed.
 void Bootstrapper::FreeThreadResources() {
   ASSERT(!IsActive());
 }
 
 } }  // namespace v8::internal