Upgrade V8 to 5.1.281.57  DO NOT MERGE

FPIIM-449

Change-Id: Id981b686b4d587ac31697662eb98bb34be42ad90
(cherry picked from commit 3b9bc31999c9787eb726ecdbfd5796bfdec32a18)
diff --git a/src/x87/assembler-x87-inl.h b/src/x87/assembler-x87-inl.h
index 7af1d02..802c80f 100644
--- a/src/x87/assembler-x87-inl.h
+++ b/src/x87/assembler-x87-inl.h
@@ -81,6 +81,10 @@
   return Assembler::target_address_at(pc_, host_);
 }
 
+Address RelocInfo::wasm_memory_reference() {
+  DCHECK(IsWasmMemoryReference(rmode_));
+  return Memory::Address_at(pc_);
+}
 
 Address RelocInfo::target_address_address() {
   DCHECK(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_)
@@ -116,6 +120,20 @@
   }
 }
 
+void RelocInfo::update_wasm_memory_reference(
+    Address old_base, Address new_base, size_t old_size, size_t new_size,
+    ICacheFlushMode icache_flush_mode) {
+  DCHECK(IsWasmMemoryReference(rmode_));
+  DCHECK(old_base <= wasm_memory_reference() &&
+         wasm_memory_reference() < old_base + old_size);
+  Address updated_reference = new_base + (wasm_memory_reference() - old_base);
+  DCHECK(new_base <= updated_reference &&
+         updated_reference < new_base + new_size);
+  Memory::Address_at(pc_) = updated_reference;
+  if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
+    Assembler::FlushICache(isolate_, pc_, sizeof(int32_t));
+  }
+}
 
 Object* RelocInfo::target_object() {
   DCHECK(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);
@@ -140,8 +158,8 @@
   if (write_barrier_mode == UPDATE_WRITE_BARRIER &&
       host() != NULL &&
       target->IsHeapObject()) {
-    host()->GetHeap()->incremental_marking()->RecordWrite(
-        host(), &Memory::Object_at(pc_), HeapObject::cast(target));
+    host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(
+        host(), this, HeapObject::cast(target));
   }
 }
 
@@ -322,6 +340,10 @@
   rmode_ = RelocInfo::NONE32;
 }
 
+Immediate::Immediate(Address x, RelocInfo::Mode rmode) {
+  x_ = reinterpret_cast<int32_t>(x);
+  rmode_ = rmode;
+}
 
 Immediate::Immediate(const ExternalReference& ext) {
   x_ = reinterpret_cast<int32_t>(ext.address());
@@ -430,6 +452,11 @@
   }
 }
 
+void Assembler::emit_b(Immediate x) {
+  DCHECK(x.is_int8() || x.is_uint8());
+  uint8_t value = static_cast<uint8_t>(x.x_);
+  *pc_++ = value;
+}
 
 void Assembler::emit_w(const Immediate& x) {
   DCHECK(RelocInfo::IsNone(x.rmode_));