Except when it didn't. They gave particular attention to nested loops with subscripted variables, exemplified by linear-algebra computations. But their algorithms behaved quite wildly on nonstandard loops. Vic Vyssotsky cooked up a nest of loops surrounding a single awful statement that filled up the maximum 10 continuation lines with triple subscripts in all permutations of several variables. That statement compiled into thousands of instructions, far more than a naively written compiler would have produced. doug