--- old/test/hotspot/jtreg/compiler/valhalla/valuetypes/ValueTypeTest.java	2019-09-17 12:58:35.000000000 +0200
+++ new/test/hotspot/jtreg/compiler/valhalla/valuetypes/ValueTypeTest.java	2019-09-17 12:58:30.000000000 +0200
@@ -753,4 +753,17 @@
         }
         WHITE_BOX.enqueueMethodForCompilation(m, level);
     }
+
+    // Unlike C2, C1 intrinsics never deoptimize System.arraycopy. Instead, we fall back to
+    // a normal method invocation when encountering flattened arrays.
+    static boolean isCompiledByC2(Method m) {
+        int CompLevel_none              = 0,         // Interpreter
+            CompLevel_simple            = 1,         // C1
+            CompLevel_limited_profile   = 2,         // C1, invocation & backedge counters
+            CompLevel_full_profile      = 3,         // C1, invocation & backedge counters + mdo
+            CompLevel_full_optimization = 4;         // C2 or JVMCI
+
+        return USE_COMPILER && !XCOMP && WHITE_BOX.isMethodCompiled(m, false) &&
+            WHITE_BOX.getMethodCompilationLevel(m, false) >= CompLevel_full_optimization;
+    }
 }