--- a/graal/com.oracle.truffle.api.dsl.test/src/com/oracle/truffle/api/dsl/test/InsertBeforeTest.java	Mon Aug 11 16:21:54 2014 +0200
+++ b/graal/com.oracle.truffle.api.dsl.test/src/com/oracle/truffle/api/dsl/test/InsertBeforeTest.java	Mon Aug 11 16:37:40 2014 +0200
@@ -120,6 +120,34 @@
     }
 
     @NodeChild("a")
+    static class InsertBefore1T6_1 extends InsertBefore1Base {
+
+        boolean g0(int a) {
+            return a == 0;
+        }
+
+        @Specialization(insertBefore = "f1", guards = "g0")
+        int f0(int a) {
+            return a;
+        }
+
+    }
+
+    @NodeChild("a")
+    static class InsertBefore1T6_2 extends InsertBefore1T6_1 {
+
+        boolean g(int a) {
+            return a == 0;
+        }
+
+        @Specialization(insertBefore = "f0", guards = "g")
+        int f(int a) {
+            return a;
+        }
+
+    }
+
+    @NodeChild("a")
     static class InsertBefore1Error1 extends InsertBefore1Base {
 
         @ExpectError("Specializations can only be inserted before specializations in superclasses.")

--- a/graal/com.oracle.truffle.dsl.processor/src/com/oracle/truffle/dsl/processor/parser/NodeParser.java	Mon Aug 11 16:21:54 2014 +0200
+++ b/graal/com.oracle.truffle.dsl.processor/src/com/oracle/truffle/dsl/processor/parser/NodeParser.java	Mon Aug 11 16:37:40 2014 +0200
@@ -580,21 +580,14 @@
             specialization.setInsertBefore(found);
         }
 
-        int endIndex = specializations.size() - 1;
-        for (int i = endIndex; i >= 0; i--) {
+        for (int i = 0; i < specializations.size(); i++) {
             SpecializationData specialization = specializations.get(i);
-            if (specialization.isGeneric() || specialization.isPolymorphic()) {
-                endIndex--;
-                continue;
-            }
-
             SpecializationData insertBefore = specialization.getInsertBefore();
             if (insertBefore != null) {
                 int insertIndex = specializations.indexOf(insertBefore);
                 if (insertIndex < i) {
-                    List<SpecializationData> range = new ArrayList<>(specializations.subList(i, endIndex + 1));
-                    specializations.removeAll(range);
-                    specializations.addAll(insertIndex, range);
+                    specializations.remove(i);
+                    specializations.add(insertIndex, specialization);
                 }
             }
         }