# HG changeset patch
# User Jaroslav Tulach <jaroslav.tulach@apidesign.org>
# Date 1426243264 -3600
# Node ID 6c1fa412c72d514d947898888336d4c1b851cf61
# Parent  fbe883b5a7934745cee4c7f098f499c76d9fbfde
Using the provided flow instead of "gt" & X_nn style

diff -r fbe883b5a793 -r 6c1fa412c72d rt/vm/src/main/java/org/apidesign/vm4brwsr/Bck2Brwsr.java
--- a/rt/vm/src/main/java/org/apidesign/vm4brwsr/Bck2Brwsr.java	Thu Mar 12 12:07:54 2015 +0100
+++ b/rt/vm/src/main/java/org/apidesign/vm4brwsr/Bck2Brwsr.java	Fri Mar 13 11:41:04 2015 +0100
@@ -422,8 +422,10 @@
      */
     public static final class Flow {
         private final MethodData m;
+        private byte[] ops;
         Flow(MethodData m) {
             this.m = m;
+            ops = new byte[m.getCode().length];
         }
         
         /** Access to bytecode of the method to analyse.
@@ -441,10 +443,46 @@
             return m.getName();
         }
         
-        public void registerCycle(int offset) {
+        public void beginLoopAt(int bci) {
+            ops[bci] |= 0x10;
         }
         
-        public void registerIf(int offset) {
+        public void beginIfAt(int bci) {
+            ops[bci] |= 0x20;
+        }
+
+
+        public void breakAt(int bci) {
+            ops[bci] |= 0x40;
+        }
+
+        public void beginElseAt(int bci) {
+            ops[bci] |= 0x80;
+        }
+
+        public void endAt(int bci) {
+            int cnt = (ops[bci] & 0x0f) + 1;
+            int rest = ops[bci] & 0xf0;
+            ops[bci] = (byte)(rest | cnt);
+        }
+        
+        boolean isFlow(int at) {
+            return ops[at] != 0;
+        }
+        boolean isLoop(int at) {
+            return (ops[at] & 0x10) != 0;
+        }
+        boolean isIf(int at) {
+            return (ops[at] & 0x20) != 0;
+        }
+        boolean isBreak(int at) {
+            return (ops[at] & 0x40) != 0;
+        }
+        boolean isElse(int at) {
+            return (ops[at] & 0x80) != 0;
+        }
+        int isEnd(int at) {
+            return (ops[at] & 0x0f);
         }
         
         /** Provider of advanced analysis of the code flow inside of
diff -r fbe883b5a793 -r 6c1fa412c72d rt/vm/src/main/java/org/apidesign/vm4brwsr/ByteCodeToJavaScript.java
--- a/rt/vm/src/main/java/org/apidesign/vm4brwsr/ByteCodeToJavaScript.java	Thu Mar 12 12:07:54 2015 +0100
+++ b/rt/vm/src/main/java/org/apidesign/vm4brwsr/ByteCodeToJavaScript.java	Fri Mar 13 11:41:04 2015 +0100
@@ -466,9 +466,13 @@
             didBranches = false;
             lastStackFrame = 0;
         } else {
-            didBranches = true;
             lastStackFrame = -1;
-            append("\n  var gt = 0;\n");
+            if (flow == null) {
+                didBranches = true;
+                append("\n  var gt = 0;\n");
+            } else {
+                didBranches = false;
+            }
         }
         
         int openBraces = 0;
@@ -486,7 +490,7 @@
             }
             if (lastStackFrame != stackMapIterator.getFrameIndex()) {
                 smapper.flush(this);
-                if (i != 0) {
+                if (flow == null && i != 0) {
                     append("    }\n");
                 }
                 if (openBraces > 64) {
@@ -500,8 +504,16 @@
                 lastStackFrame = stackMapIterator.getFrameIndex();
                 lmapper.syncWithFrameLocals(stackMapIterator.getFrameLocals());
                 smapper.syncWithFrameStack(stackMapIterator.getFrameStack());
-                append("    X_" + i).append(": for (;;) { IF: if (gt <= " + i + ") {\n");
-                openBraces++;
+                if (flow == null) {
+                    append("    X_" + i).append(": for (;;) { IF: if (gt <= " + i + ") {\n");
+                    openBraces++;
+                } else {
+                    if (!flow.isFlow(i)) {
+                        if (i != 0) {
+                            throw new IOException("Expecting flow suggestion at " + i);
+                        }
+                    }
+                }
                 changeInCatch = true;
             } else {
                 debug("    /* " + i + " */ ");
@@ -510,6 +522,20 @@
                 append("try {");
                 previousTrap = trap.current();
             }
+            if (flow != null) {
+                if (flow.isLoop(i)) {
+                    append("    for (;;) {\n");
+                } 
+                if (flow.isBreak(i)) {
+                    append("\n    break;");
+                }
+                for (int j = 0; j < flow.isEnd(i); j++) {
+                    append("\n    }");
+                }
+                if (flow.isElse(i)) {
+                    append("    else {\n");
+                }
+            }
             final int c = readUByte(byteCodes, i);
             switch (c) {
                 case opc_aload_0:
@@ -1091,8 +1117,10 @@
                     break;
                 case opc_goto: {
                     smapper.flush(this);
-                    int indx = i + readShortArg(byteCodes, i);
-                    goTo(this, flow, i, indx, topMostLabel);
+                    if (flow == null) {
+                        int indx = i + readShortArg(byteCodes, i);
+                        goTo(this, flow, i, indx, topMostLabel);
+                    }
                     i += 2;
                     break;
                 }
@@ -2275,6 +2303,13 @@
     }
 
     private static void goTo(Appendable out, Flow flow, int current, int to, int canBack) throws IOException {
+        if (flow != null) {
+            if (flow.isIf(current)) {
+                out.append("{");
+                return;
+            }
+            throw new IllegalStateException("Opn: ");
+        }
         if (to < current) {
             if (canBack < to) {
                 out.append("{ gt = 0; continue X_" + to + "; }");