Re: [Chicken-janitors] #1604: fixnum arithmetic is ignored

[Chicken Trac]

#1604: fixnum arithmetic is ignored
---------------------------------+-------------------
            Reporter:  sjamaan   |      Owner:
                Type:  defect    |     Status:  new
            Priority:  major     |  Milestone:  5.1
           Component:  compiler  |    Version:  5.0.0
          Resolution:            |   Keywords:
Estimated difficulty:  medium    |
---------------------------------+-------------------
Description changed by sjamaan:

Old description:

> As reported by chickendan on IRC:
>
> ```
> ;; csc -O5 -strict-types -fixnum-arithmetic: 7.964s
> ;; csc -O5 -strict-types:                    8.105s
> ;; csc -O5 -strict-types (and fx functions): 0.246s
> ;;; c/nim -O3 baseline:                       0.211s
>
> (define (fib n)
>   (if (or (= n 0) (= n 1))
>       n
>       (+ (fib (- n 1)) (fib (- n 2)))))
>
> (let loop ((n 0))
>   (when (< n 35)
>     (print "n=" n " => " (fib n))
>     (loop (+ n 1))))
> ```
>
> This program should use fixnum ops when declaring fixnum arithmetic.
> Also, when wrapping `fib`'s body in an `assume`, it still compiles to
> `C_s_a_i_plus` calls rather than `C_a_i_fixnum_plus` or even just
> `C_s_a_u_i_integer_plus`.
>
> I think we should take a look before releasing 5.1, the fact `fixnum-
> arithmetic` is ignored may not be a big issue, but it is rather worrying
> that the specializations aren't used.

New description:

 As reported by chickendan on IRC:

 {{{
 ;; csc -O5 -strict-types -fixnum-arithmetic: 7.964s
 ;; csc -O5 -strict-types:                    8.105s
 ;; csc -O5 -strict-types (and fx functions): 0.246s
 ;;; c/nim -O3 baseline:                       0.211s

 (define (fib n)
   (if (or (= n 0) (= n 1))
       n
       (+ (fib (- n 1)) (fib (- n 2)))))

 (let loop ((n 0))
   (when (< n 35)
     (print "n=" n " => " (fib n))
     (loop (+ n 1))))
 }}}

 This program should use fixnum ops when declaring fixnum arithmetic.
 Also, when wrapping `fib`'s body in an `assume`, it still compiles to
 `C_s_a_i_plus` calls rather than `C_a_i_fixnum_plus` or even just
 `C_s_a_u_i_integer_plus`.

 I think we should take a look before releasing 5.1, the fact `fixnum-
 arithmetic` is ignored may not be a big issue, but it is rather worrying
 that the specializations aren't used.

--

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Ticket URL: <https://bugs.call-cc.org/ticket/1604#comment:1>
CHICKEN Scheme <https://www.call-cc.org/>
CHICKEN Scheme is a compiler for the Scheme programming language.