Node * peel_while_loop (whileNode *);

// Loop peeling transformation for while:
//
// while (expr) stmt;
// =>
// if (expr) {
//      stmt;
//      while (expr) stmt;
// }
//
// Returns a node that is the result of transforming the while node into the 
// if/while node described above.

Node * LoopPeelingChanger::peel_while_loop (whileNode *p) {

        // Build a new block to contain the If stmt body:
        //      { }

        blockNode *newblock = new blockNode (NULL, NULL);

        // Put the copy of the body of the While loop into the
        // if stmt body:
        //      { stmt; }

        newblock->stmts().push_back (
                (stmtNode *) clone_changer::clone(p->body()));

        // Make a new copy of the While loop.  This is important because the 
        // changer is going to change 'this' While loop with our new peeled 
        // loop.

        whileNode *newwhile = new whileNode (
                (exprNode *) clone_changer::clone(p->cond()),
                (stmtNode *) clone_changer::clone(p->body()));

        // Put the copy of the While loop after the While loop body in the If 
        // body:
        //      { stmt; while (expr) stmt; }

        newblock->stmts().push_back ((stmtNode*) newwhile);

        // Wrap everything up in an If stmt with a copy of the While condition 
        // and return it:
        //      if (expr) { stmt; while (expr) stmt; }

        ifNode *newif = new ifNode (
                (exprNode *) clone_changer::clone(p->cond()), NULL, newblock);
        return newif;
}