tests/arith.pure.lisp

   1 ;;;; arithmetic tests with no side effects
   2
   3 ;;;; This software is part of the SBCL system. See the README file for
   4 ;;;; more information.
   5 ;;;;
   6 ;;;; While most of SBCL is derived from the CMU CL system, the test
   7 ;;;; files (like this one) were written from scratch after the fork
   8 ;;;; from CMU CL.
   9 ;;;;
  10 ;;;; This software is in the public domain and is provided with
  11 ;;;; absolutely no warranty. See the COPYING and CREDITS files for
  12 ;;;; more information.
  13
  14 (cl:in-package :cl-user)
  15
  16 ;;; Once upon a time, in the process of porting CMUCL's SPARC backend
  17 ;;; to SBCL, multiplications were excitingly broken.  While it's
  18 ;;; unlikely that anything with such fundamental arithmetic errors as
  19 ;;; these are going to get this far, it's probably worth checking.
  20 (macrolet ((test (op res1 res2)
  21              `(progn
  22                (assert (= (,op 4 2) ,res1))
  23                (assert (= (,op 2 4) ,res2))
  24                (assert (= (funcall (compile nil (lambda (x y) (,op x y))) 4 2)
  25                         ,res1))
  26                (assert (= (funcall (compile nil (lambda (x y) (,op x y))) 2 4)
  27                         ,res2)))))
  28   (test + 6 6)
  29   (test - 2 -2)
  30   (test * 8 8)
  31   (test / 2 1/2)
  32   (test expt 16 16))
  33
  34 ;;; In a bug reported by Wolfhard Buss on cmucl-imp 2002-06-18 (BUG
  35 ;;; 184), sbcl didn't catch all divisions by zero, notably divisions
  36 ;;; of bignums and ratios by 0.  Fixed in sbcl-0.7.6.13.
  37 (assert (raises-error? (/ 2/3 0) division-by-zero))
  38 (assert (raises-error? (/ (1+ most-positive-fixnum) 0) division-by-zero))
  39
  40 ;;; In a bug reported by Raymond Toy on cmucl-imp 2002-07-18, (COERCE
  41 ;;; <RATIONAL> '(COMPLEX FLOAT)) was failing to return a complex
  42 ;;; float; a patch was given by Wolfhard Buss cmucl-imp 2002-07-19.
  43 (assert (= (coerce 1 '(complex float)) #c(1.0 0.0)))
  44 (assert (= (coerce 1/2 '(complex float)) #c(0.5 0.0)))
  45 (assert (= (coerce 1.0d0 '(complex float)) #c(1.0d0 0.0d0)))
  46
  47 ;;; COERCE also sometimes failed to verify that a particular coercion
  48 ;;; was possible (in particular coercing rationals to bounded float
  49 ;;; types.
  50 (assert (raises-error? (coerce 1 '(float 2.0 3.0)) type-error))
  51 (assert (raises-error? (coerce 1 '(single-float -1.0 0.0)) type-error))
  52 (assert (eql (coerce 1 '(single-float -1.0 2.0)) 1.0))
  53
  54 ;;; ANSI says MIN and MAX should signal TYPE-ERROR if any argument
  55 ;;; isn't REAL. SBCL 0.7.7 didn't in the 1-arg case. (reported as a
  56 ;;; bug in CMU CL on #lisp IRC by lrasinen 2002-09-01)
  57 (assert (null (ignore-errors (min '(1 2 3)))))
  58 (assert (= (min -1) -1))
  59 (assert (null (ignore-errors (min 1 #(1 2 3)))))
  60 (assert (= (min 10 11) 10))
  61 (assert (null (ignore-errors (min (find-package "CL") -5.0))))
  62 (assert (= (min 5.0 -3) -3))
  63 (assert (null (ignore-errors (max #c(4 3)))))
  64 (assert (= (max 0) 0))
  65 (assert (null (ignore-errors (max "MIX" 3))))
  66 (assert (= (max -1 10.0) 10.0))
  67 (assert (null (ignore-errors (max 3 #'max))))
  68 (assert (= (max -3 0) 0))
  69
  70 ;;; (CEILING x 2^k) was optimized incorrectly
  71 (loop for divisor in '(-4 4)
  72    for ceiler = (compile nil `(lambda (x)
  73                                 (declare (fixnum x))
  74                                 (declare (optimize (speed 3)))
  75                                 (ceiling x ,divisor)))
  76    do (loop for i from -5 to 5
  77          for exact-q = (/ i divisor)
  78          do (multiple-value-bind (q r)
  79                 (funcall ceiler i)
  80               (assert (= (+ (* q divisor) r) i))
  81               (assert (<= exact-q q))
  82               (assert (< q (1+ exact-q))))))
  83
  84 ;;; CEILING had a corner case, spotted by Paul Dietz
  85 (assert (= (ceiling most-negative-fixnum (1+ most-positive-fixnum)) -1))
  86
  87 ;;; give any optimizers of constant multiplication a light testing.
  88 ;;; 100 may seem low, but (a) it caught CSR's initial errors, and (b)
  89 ;;; before checking in, CSR tested with 10000.  So one hundred
  90 ;;; checkins later, we'll have doubled the coverage.
  91 (dotimes (i 100)
  92   (let* ((x (random most-positive-fixnum))
  93          (x2 (* x 2))
  94          (x3 (* x 3)))
  95     (let ((fn (handler-bind ((sb-ext:compiler-note #'error))
  96                 (compile nil
  97                          `(lambda (y)
  98                             (declare (optimize speed) (type (integer 0 3) y))
  99                             (* y ,x))))))
 100       (unless (and (= (funcall fn 0) 0)
 101                    (= (funcall fn 1) x)
 102                    (= (funcall fn 2) x2)
 103                    (= (funcall fn 3) x3))
 104         (error "bad results for ~D" x)))))
 105
 106 ;;; Bugs reported by Paul Dietz:
 107
 108 ;;; (GCD 0 x) must return (abs x)
 109 (dolist (x (list -10 (* 3 most-negative-fixnum)))
 110   (assert (= (gcd 0 x) (abs x))))
 111 ;;; LCM returns a non-negative number
 112 (assert (= (lcm 4 -10) 20))
 113 (assert (= (lcm 0 0) 0))
 114
 115 ;;; PPC bignum arithmetic bug:
 116 (multiple-value-bind (quo rem)
 117     (truncate 291351647815394962053040658028983955 10000000000000000000000000)
 118   (assert (= quo 29135164781))
 119   (assert (= rem 5394962053040658028983955)))
 120
 121 ;;; x86 LEA bug:
 122 (assert (= (funcall
 123             (compile nil '(lambda (x) (declare (bit x)) (+ x #xf0000000)))
 124             1)
 125            #xf0000001))
 126
 127 ;;; LOGBITP on bignums:
 128 (dolist (x '(((1+ most-positive-fixnum) 1 nil)
 129              ((1+ most-positive-fixnum) -1 t)
 130              ((1+ most-positive-fixnum) (1+ most-positive-fixnum) nil)
 131              ((1+ most-positive-fixnum) (1- most-negative-fixnum) t)
 132              (1 (ash most-negative-fixnum 1) nil)
 133              (29 most-negative-fixnum t)
 134              (30 (ash most-negative-fixnum 1) t)
 135              (31 (ash most-negative-fixnum 1) t)
 136              (64 (ash most-negative-fixnum 36) nil)
 137              (65 (ash most-negative-fixnum 36) t)))
 138   (destructuring-bind (index int result) x
 139     (assert (eq (eval `(logbitp ,index ,int)) result))))
 140
 141 ;;; off-by-1 type inference error for %DPB and %DEPOSIT-FIELD:
 142 (let ((f (compile nil '(lambda (b)
 143                         (integer-length (dpb b (byte 4 28) -1005))))))
 144   (assert (= (funcall f 1230070) 32)))
 145 (let ((f (compile nil '(lambda (b)
 146                         (integer-length (deposit-field b (byte 4 28) -1005))))))
 147   (assert (= (funcall f 1230070) 32)))
 148
 149 ;;; type inference leading to an internal compiler error:
 150 (let ((f (compile nil '(lambda (x)
 151                         (declare (type fixnum x))
 152                         (ldb (byte 0 0) x)))))
 153   (assert (= (funcall f 1) 0))
 154   (assert (= (funcall f most-positive-fixnum) 0))
 155   (assert (= (funcall f -1) 0)))
 156
 157 ;;; Alpha bignum arithmetic bug:
 158 (assert (= (* 966082078641 419216044685) 404997107848943140073085))