twitter-user-@ladyaeva.md

typed.rkt

#lang typed/racket

(define-type Vec2 (Vector Flonum Flonum))

(: mad (Flonum Flonum Flonum . -> . Flonum))
(define (mad a b c)
  (+ (* a b) c))

(: vec2-mad (Vec2 Vec2 Vec2 . -> . Vec2))
(define (vec2-mad a b c)
  (define out (vector 0.0 0.0))
  (vector-set!
   out 0
   (mad (vector-ref a 0)
        (vector-ref b 0)
        (vector-ref c 0)))
  (vector-set!
   out 1
   (mad (vector-ref a 1)
        (vector-ref b 1)
        (vector-ref c 1)))
  out)

(: flops (Integer -> Void))
(define (flops iterations)
  (define start-seconds (/ (current-inexact-milliseconds) 1000))
  (for ([i (in-range iterations)])
    (vec2-mad (vector (random) (random))
              (vector (random) (random))
              (vector (random) (random))))
  (define stop-seconds (/ (current-inexact-milliseconds) 1000))
  (define delta-seconds (- stop-seconds start-seconds))
  (define ops (* iterations 6))
  (define flops (/ ops delta-seconds))
  (printf "ran for ~a seconds at ~a operations per second\n" delta-seconds flops))

(module+ main
  (flops 10000000))

untyped.rkt

#lang racket
(require racket/unsafe/ops)

(define (mad a b c)
  (unsafe-fl+ (unsafe-fl* a b) c))

(define (vec2-mad a b c)
  (define out (vector 0.0 0.0))
  (unsafe-vector-set!
   out 0
   (mad (unsafe-vector-ref a 0)
        (unsafe-vector-ref b 0)
        (unsafe-vector-ref c 0)))
  (unsafe-vector-set!
   out 1
   (mad (unsafe-vector-ref a 1)
        (unsafe-vector-ref b 1)
        (unsafe-vector-ref c 1)))
  out)

(define (flops iterations)
  (define start-seconds (/ (current-inexact-milliseconds) 1000))
  (for ([i (in-range iterations)])
    (vec2-mad (vector (random) (random))
              (vector (random) (random))
              (vector (random) (random))))
  (define stop-seconds (/ (current-inexact-milliseconds) 1000))
  (define delta-seconds (- stop-seconds start-seconds))
  (define ops (* iterations 6))
  (define flops (/ ops delta-seconds))
  (printf "ran for ~a seconds at ~a operations per second\n" delta-seconds flops))

(module+ main
  (flops 10000000))