C2: arraycopy with same non escaping src and dest but different positions causes wrong execution

The patch below applied to an existing test case causes fails with an incorrect result.

diff -r d003b3ef8b60 test/hotspot/jtreg/compiler/escapeAnalysis/TestSelfArrayCopy.java
--- a/test/hotspot/jtreg/compiler/escapeAnalysis/TestSelfArrayCopy.java Mon Sep 16 09:28:54 2019 +0200
+++ b/test/hotspot/jtreg/compiler/escapeAnalysis/TestSelfArrayCopy.java Mon Sep 16 11:58:55 2019 +0200
@@ -43,7 +43,7 @@
         // Non-escaping allocation
         Integer[] array = {rI1, rI2};
         // Arraycopy with src == dst
- System.arraycopy(array, 0, array, 0, array.length - 1);
+ System.arraycopy(array, 0, array, 1, 1);
         if (b) {
             // Uncommon trap
             System.out.println(array[0]);
@@ -52,7 +52,7 @@
     }
 
     public static void main(String[] args) {
- int expected = rI1 + rI2;
+ int expected = rI1 + rI1;
         // Trigger compilation
         for (int i = 0; i < 20_000; ++i) {
             int result = test();
@@ -60,5 +60,10 @@
                 throw new RuntimeException("Incorrect result: " + result + " != " + expected);
             }
         }
+ b = true;
+ int result = test();
+ if (result != expected) {
+ throw new RuntimeException("Incorrect result: " + result + " != " + expected);
+ }
     }
 }