Example #1
0
 private boolean insertBreak(RegionStack stack, BlockNode loopExit, Edge exitEdge) {
   BlockNode exit = exitEdge.getTarget();
   BlockNode insertBlock = null;
   boolean confirm = false;
   // process special cases
   if (loopExit == exit) {
     // try/catch at loop end
     BlockNode source = exitEdge.getSource();
     if (source.contains(AType.CATCH_BLOCK) && source.getSuccessors().size() == 2) {
       BlockNode other = BlockUtils.selectOther(loopExit, source.getSuccessors());
       if (other != null) {
         other = BlockUtils.skipSyntheticSuccessor(other);
         if (other.contains(AType.EXC_HANDLER)) {
           insertBlock = source;
           confirm = true;
         }
       }
     }
   }
   if (!confirm) {
     while (exit != null) {
       if (insertBlock != null && isPathExists(loopExit, exit)) {
         // found cross
         if (canInsertBreak(insertBlock)) {
           confirm = true;
           break;
         }
         return false;
       }
       insertBlock = exit;
       List<BlockNode> cs = exit.getCleanSuccessors();
       exit = cs.size() == 1 ? cs.get(0) : null;
     }
   }
   if (!confirm) {
     return false;
   }
   InsnNode breakInsn = new InsnNode(InsnType.BREAK, 0);
   insertBlock.getInstructions().add(breakInsn);
   stack.addExit(exit);
   // add label to 'break' if needed
   addBreakLabel(exitEdge, exit, breakInsn);
   return true;
 }