ART: Arm64 optimizing compiler intrinsics

Implement most intrinsics for the optimizing compiler for Arm64.

Change-Id: Idb459be09f0524cb9aeab7a5c7fccb1c6b65a707
diff --git a/compiler/optimizing/intrinsics_x86_64.h b/compiler/optimizing/intrinsics_x86_64.h
index c1fa99c..dfae7fa 100644
--- a/compiler/optimizing/intrinsics_x86_64.h
+++ b/compiler/optimizing/intrinsics_x86_64.h
@@ -70,7 +70,7 @@
  private:
   X86_64Assembler* GetAssembler();
 
-  ArenaAllocator* GetArena();
+  ArenaAllocator* GetAllocator();
 
   CodeGeneratorX86_64* codegen_;