diff -r ea12a3bb4b33 -r 4fef6b767f61 rt/vm/src/main/java/org/apidesign/vm4brwsr/Bck2Brwsr.java
--- a/rt/vm/src/main/java/org/apidesign/vm4brwsr/Bck2Brwsr.java	Tue Feb 24 11:12:53 2015 +0100
+++ b/rt/vm/src/main/java/org/apidesign/vm4brwsr/Bck2Brwsr.java	Wed Mar 11 18:58:39 2015 +0100
@@ -82,12 +82,12 @@
     private final Resources res;
     private final Boolean extension;
     private final StringArray classpath;
+    private final Flow.Analyzer flow;
 
     private Bck2Brwsr(
-            ObfuscationLevel level, 
-            StringArray exported, StringArray classes, StringArray resources, 
-            Resources res, 
-            Boolean extension, StringArray classpath
+        ObfuscationLevel level, StringArray exported,
+        StringArray classes, StringArray resources, Resources res,
+        Boolean extension, StringArray classpath, Flow.Analyzer flow
     ) {
         this.level = level;
         this.exported = exported;
@@ -96,6 +96,7 @@
         this.res = res;
         this.extension = extension;
         this.classpath = classpath;
+        this.flow = flow;
     }
     
     /** Helper method to generate virtual machine from bytes served by a <code>resources</code>
@@ -135,7 +136,7 @@
         return new Bck2Brwsr(
             ObfuscationLevel.NONE, 
             new StringArray(), new StringArray(), new StringArray(), 
-            null, false, null
+            null, false, null, null
         );
     }
     
@@ -156,7 +157,7 @@
     public Bck2Brwsr addExported(String... exported) {
         return new Bck2Brwsr(
             level, this.exported.addAndNew(exported), 
-            classes, resources, res, extension, classpath
+            classes, resources, res, extension, classpath, flow
         );
     }
 
@@ -197,7 +198,7 @@
         } else {
             return new Bck2Brwsr(level, exported, 
                 this.classes.addAndNew(classes), resources, res,
-                extension, classpath);
+                extension, classpath, flow);
         }
     }
     
@@ -217,7 +218,7 @@
             return this;
         } else {
             return new Bck2Brwsr(level, exported, this.classes, 
-                this.resources.addAndNew(resources), res, extension, classpath
+                this.resources.addAndNew(resources), res, extension, classpath, flow
             );
         }
     }
@@ -231,7 +232,7 @@
      * @since 0.5
      */
     public Bck2Brwsr obfuscation(ObfuscationLevel level) {
-        return new Bck2Brwsr(level, exported, classes, resources, res, extension, classpath);
+        return new Bck2Brwsr(level, exported, classes, resources, res, extension, classpath, flow);
     }
     
     /** A way to change the provider of additional resources (classes) for the 
@@ -245,7 +246,7 @@
     public Bck2Brwsr resources(Resources res) {
         return new Bck2Brwsr(
             level, exported, classes, resources, 
-            res, extension, classpath
+            res, extension, classpath, flow
         );
     }
 
@@ -272,7 +273,7 @@
         return new Bck2Brwsr(
             level, exported, classes, 
             resources, res, true, 
-            StringArray.asList(classpath)
+            StringArray.asList(classpath), flow
         );
     }
     
@@ -289,7 +290,7 @@
     public Bck2Brwsr standalone(boolean includeVM) {
         return new Bck2Brwsr(
             level, exported, classes, resources, 
-            res, includeVM ? false : null, null
+            res, includeVM ? false : null, null, flow
         );
     }
 
@@ -319,6 +320,21 @@
         return resources(new LdrRsrcs(loader, ignoreBootClassPath));
     }
     
+    /** A way to register flow analyzer. Such analyzer can optimize the
+     * representation of cycles inside of method bodies.
+     * 
+     * @param flow the analyzer to be consulted with each method body
+     * @return new instance of the compiler with all values being the same, just 
+     *   different flow analyzer
+     * @since 0.15
+     */
+    public Bck2Brwsr flowAnalyzer(Flow.Analyzer flow) {
+        return new Bck2Brwsr(
+            level, exported, classes, resources, res, 
+            extension, classpath, flow
+        );
+    }
+    
     /** Generates virtual machine based on previous configuration of the 
      * compiler.
      * 
@@ -373,6 +389,10 @@
     StringArray classpath() {
         return classpath;
     }
+    
+    Flow.Analyzer flow() {
+        return flow;
+    }
 
     /** Provider of resources (classes and other files). The 
      * {@link #generate(java.lang.Appendable, org.apidesign.vm4brwsr.Bck2Brwsr.Resources, java.lang.String[]) 
@@ -391,4 +411,51 @@
          */
         public InputStream get(String resource) throws IOException;
     }
+
+    /** Represents control flow inside single method.
+     * Passed into {@link Analyzer#analyze(byte[], org.apidesign.vm4brwsr.Bck2Brwsr.Flow)}
+     * method that can be registed via {@link Bck2Brwsr#flowAnalyzer(org.apidesign.vm4brwsr.Bck2Brwsr.Flow.Analyzer)}
+     * method.
+     * 
+     * @since 0.15
+     */
+    public static final class Flow {
+        private final byte[] byteCode;
+        Flow(byte[] byteCode) {
+            this.byteCode = byteCode;
+        }
+        
+        /** Access to bytecode of the method to analyse.
+         * 
+         * @return unmodifiable bytecode of the instructions in the method body
+         */
+        public byte[] getMethodByteCode() {
+            return byteCode;
+        }
+        
+        public void registerCycle(int offset) {
+        }
+        
+        public void registerIf(int offset) {
+        }
+        
+        /** Provider of advanced analysis of the code flow inside of
+         * method bodies. Register via {@link Bck2Brwsr#flowAnalyzer(org.apidesign.vm4brwsr.Bck2Brwsr.Flow.Analyzer)}
+         * when constructing the {@link Bck2Brwsr#newCompiler() compiler}.
+         * 
+         * @since 0.15
+         */
+        public interface Analyzer {
+            /** Called to analyze method bodies and offer better control flow.
+             * 
+             * 
+             * @param request flow computation request and also a
+             *    callback interface with methods to define the flow
+             * @return <code>true</code> if the analysis was successful,
+             *   <code>false</code> otherwise
+             */
+            public boolean analyze(Flow request);
+        }
+    }
+    
 }