--- a/hotspot/src/cpu/aarch64/vm/stubGenerator_aarch64.cpp	Sat Feb 06 04:09:47 2016 -0800
+++ b/hotspot/src/cpu/aarch64/vm/stubGenerator_aarch64.cpp	Fri Feb 05 03:55:51 2016 -0800
@@ -792,6 +792,12 @@
     assert_different_registers(s, d, count, rscratch1);
 
     Label again, large, small;
+    const char *stub_name;
+    if (direction == copy_forwards)
+      stub_name = "foward_copy_longs";
+    else
+      stub_name = "backward_copy_longs";
+    StubCodeMark mark(this, "StubRoutines", stub_name);
     __ align(CodeEntryAlignment);
     __ bind(start);
     __ cmp(count, 8);
@@ -1160,8 +1166,11 @@
       // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)
       BLOCK_COMMENT("Entry:");
     }
-    __ cmp(d, s);
-    __ br(Assembler::LS, nooverlap_target);
+
+    // use fwd copy when (d-s) above_equal (count*size)
+    __ sub(rscratch1, d, s);
+    __ cmp(rscratch1, count, Assembler::LSL, exact_log2(size));
+    __ br(Assembler::HS, nooverlap_target);
 
     if (is_oop) {
       __ push(RegSet::of(d, count), sp);