Add mips64 port.

src/serialize.cc

Index: src/serialize.cc
diff --git a/src/serialize.cc b/src/serialize.cc
index ca7adcbaa1a0910f371b4918b10949ba79cd7c91..7d6a4820a3262282582acc12b64e85d33aaaa375 100644
--- a/src/serialize.cc
+++ b/src/serialize.cc
@@ -1108,7 +1108,8 @@ void Deserializer::ReadChunk(Object** current,
       // allocation point and write a pointer to it to the current object.
       ALL_SPACES(kBackref, kPlain, kStartOfObject)
       ALL_SPACES(kBackrefWithSkip, kPlain, kStartOfObject)
-#if defined(V8_TARGET_ARCH_MIPS) || V8_OOL_CONSTANT_POOL
+#if defined(V8_TARGET_ARCH_MIPS) || V8_OOL_CONSTANT_POOL || \
+    defined(V8_TARGET_ARCH_MIPS64)
       // Deserialize a new object from pointer found in code and write
       // a pointer to it to the current object. Required only for MIPS or ARM
       // with ool constant pool, and omitted on the other architectures because
@@ -1326,7 +1327,8 @@ int Serializer::RootIndex(HeapObject* heap_object, HowToCode from) {
   for (int i = 0; i < root_index_wave_front_; i++) {
     Object* root = heap->roots_array_start()[i];
     if (!root->IsSmi() && root == heap_object) {
-#if defined(V8_TARGET_ARCH_MIPS) || V8_OOL_CONSTANT_POOL
+#if defined(V8_TARGET_ARCH_MIPS) || V8_OOL_CONSTANT_POOL || \
+    defined(V8_TARGET_ARCH_MIPS64)
       if (from == kFromCode) {
         // In order to avoid code bloat in the deserializer we don't have
         // support for the encoding that specifies a particular root should