if (VM.VerifyAssertions) VM.assert(node.depth == 0);
if (VM.VerifyAssertions) VM._assert(node.depth == 0);
  private void setDepth(OPT_IR ir, OPT_LSTNode node, int depth) {    if (VM.VerifyAssertions) VM.assert(node.depth == 0);    node.depth = depth;    for (Enumeration e = node.getChildren();	 e.hasMoreElements();) {      setDepth(ir, (OPT_LSTNode)e.nextElement(), depth+1);    }    OPT_BitVector loop = node.loop;    if (loop != null) {      for (int i = 0; i < loop.length(); i++) {	if (loop.get(i)) {	  OPT_BasicBlock bb = ir.getBasicBlock(i);	  if (loopMap.get(bb) == null) {	    loopMap.put(bb, node);	  }	}      }    }  }