iexpr_hash
(iexpr_hash(np->u.expr.left) +
iexpr_hash(np->u.expr.right)));
return (iexpr_hash(np->u.event.ename) +
iexpr_hash(np->u.event.epname));
iexpr_hash(np->u.func.arglist));
unsigned idx = iexpr_hash(np) % IEXPRSZ;
unsigned idx = iexpr_hash(np) % IEXPRSZ;
struct iexpr *cp = Cache[iexpr_hash(np) % IEXPRSZ];