--- old/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core.common/src/org/graalvm/compiler/core/common/cfg/AbstractBlockBase.java	2019-03-09 03:55:57.756605297 +0100
+++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core.common/src/org/graalvm/compiler/core/common/cfg/AbstractBlockBase.java	2019-03-09 03:55:57.388602694 +0100
@@ -24,6 +24,8 @@
 
 package org.graalvm.compiler.core.common.cfg;
 
+import java.util.Comparator;
+
 public abstract class AbstractBlockBase<T extends AbstractBlockBase<T>> {
 
     protected int id;
@@ -171,4 +173,13 @@
     public int hashCode() {
         return id;
     }
+
+    public static class BlockIdComparator implements Comparator<AbstractBlockBase<?>> {
+        @Override
+        public int compare(AbstractBlockBase<?> o1, AbstractBlockBase<?> o2) {
+            return Integer.compare(o1.getId(), o2.getId());
+        }
+    }
+
+    public static final BlockIdComparator BLOCK_ID_COMPARATOR = new BlockIdComparator();
 }