;;;; arithmetic tests with no side effects ;;;; This software is part of the SBCL system. See the README file for ;;;; more information. ;;;; ;;;; While most of SBCL is derived from the CMU CL system, the test ;;;; files (like this one) were written from scratch after the fork ;;;; from CMU CL. ;;;; ;;;; This software is in the public domain and is provided with ;;;; absolutely no warranty. See the COPYING and CREDITS files for ;;;; more information. (cl:in-package :cl-user) ;;; Once upon a time, in the process of porting CMUCL's SPARC backend ;;; to SBCL, multiplications were excitingly broken. While it's ;;; unlikely that anything with such fundamental arithmetic errors as ;;; these are going to get this far, it's probably worth checking. (macrolet ((test (op res1 res2) `(progn (assert (= (,op 4 2) ,res1)) (assert (= (,op 2 4) ,res2)) (assert (= (funcall (compile nil (lambda (x y) (,op x y))) 4 2) ,res1)) (assert (= (funcall (compile nil (lambda (x y) (,op x y))) 2 4) ,res2))))) (test + 6 6) (test - 2 -2) (test * 8 8) (test / 2 1/2) (test expt 16 16)) ;;; In a bug reported by Wolfhard Buss on cmucl-imp 2002-06-18 (BUG ;;; 184), sbcl didn't catch all divisions by zero, notably divisions ;;; of bignums and ratios by 0. Fixed in sbcl-0.7.6.13. (assert (raises-error? (/ 2/3 0) division-by-zero)) (assert (raises-error? (/ (1+ most-positive-fixnum) 0) division-by-zero)) ;;; In a bug reported by Raymond Toy on cmucl-imp 2002-07-18, (COERCE ;;; '(COMPLEX FLOAT)) was failing to return a complex ;;; float; a patch was given by Wolfhard Buss cmucl-imp 2002-07-19. (assert (= (coerce 1 '(complex float)) #c(1.0 0.0))) (assert (= (coerce 1/2 '(complex float)) #c(0.5 0.0))) (assert (= (coerce 1.0d0 '(complex float)) #c(1.0d0 0.0d0))) ;;; COERCE also sometimes failed to verify that a particular coercion ;;; was possible (in particular coercing rationals to bounded float ;;; types. (assert (raises-error? (coerce 1 '(float 2.0 3.0)) type-error)) (assert (raises-error? (coerce 1 '(single-float -1.0 0.0)) type-error)) (assert (eql (coerce 1 '(single-float -1.0 2.0)) 1.0)) ;;; ANSI says MIN and MAX should signal TYPE-ERROR if any argument ;;; isn't REAL. SBCL 0.7.7 didn't in the 1-arg case. (reported as a ;;; bug in CMU CL on #lisp IRC by lrasinen 2002-09-01) (assert (null (ignore-errors (min '(1 2 3))))) (assert (= (min -1) -1)) (assert (null (ignore-errors (min 1 #(1 2 3))))) (assert (= (min 10 11) 10)) (assert (null (ignore-errors (min (find-package "CL") -5.0)))) (assert (= (min 5.0 -3) -3)) (assert (null (ignore-errors (max #c(4 3))))) (assert (= (max 0) 0)) (assert (null (ignore-errors (max "MIX" 3)))) (assert (= (max -1 10.0) 10.0)) (assert (null (ignore-errors (max 3 #'max)))) (assert (= (max -3 0) 0)) ;;; (CEILING x 2^k) was optimized incorrectly (loop for divisor in '(-4 4) for ceiler = (compile nil `(lambda (x) (declare (fixnum x)) (declare (optimize (speed 3))) (ceiling x ,divisor))) do (loop for i from -5 to 5 for exact-q = (/ i divisor) do (multiple-value-bind (q r) (funcall ceiler i) (assert (= (+ (* q divisor) r) i)) (assert (<= exact-q q)) (assert (< q (1+ exact-q)))))) ;;; (TRUNCATE x 2^k) was optimized incorrectly (loop for divisor in '(-4 4) for truncater = (compile nil `(lambda (x) (declare (fixnum x)) (declare (optimize (speed 3))) (truncate x ,divisor))) do (loop for i from -9 to 9 for exact-q = (/ i divisor) do (multiple-value-bind (q r) (funcall truncater i) (assert (= (+ (* q divisor) r) i)) (assert (<= (abs q) (abs exact-q))) (assert (< (abs exact-q) (1+ (abs q))))))) ;;; CEILING had a corner case, spotted by Paul Dietz (assert (= (ceiling most-negative-fixnum (1+ most-positive-fixnum)) -1)) ;;; give any optimizers of constant multiplication a light testing. ;;; 100 may seem low, but (a) it caught CSR's initial errors, and (b) ;;; before checking in, CSR tested with 10000. So one hundred ;;; checkins later, we'll have doubled the coverage. (dotimes (i 100) (let* ((x (random most-positive-fixnum)) (x2 (* x 2)) (x3 (* x 3))) (let ((fn (handler-bind ((sb-ext:compiler-note (lambda (c) (when (<= x3 most-positive-fixnum) (error c))))) (compile nil `(lambda (y) (declare (optimize speed) (type (integer 0 3) y)) (* y ,x)))))) (unless (and (= (funcall fn 0) 0) (= (funcall fn 1) x) (= (funcall fn 2) x2) (= (funcall fn 3) x3)) (error "bad results for ~D" x))))) ;;; Bugs reported by Paul Dietz: ;;; (GCD 0 x) must return (abs x) (dolist (x (list -10 (* 3 most-negative-fixnum))) (assert (= (gcd 0 x) (abs x)))) ;;; LCM returns a non-negative number (assert (= (lcm 4 -10) 20)) (assert (= (lcm 0 0) 0)) ;;; PPC bignum arithmetic bug: (multiple-value-bind (quo rem) (truncate 291351647815394962053040658028983955 10000000000000000000000000) (assert (= quo 29135164781)) (assert (= rem 5394962053040658028983955))) ;;; x86 LEA bug: (assert (= (funcall (compile nil '(lambda (x) (declare (bit x)) (+ x #xf0000000))) 1) #xf0000001)) ;;; LOGBITP on bignums: (dolist (x '(((1+ most-positive-fixnum) 1 nil) ((1+ most-positive-fixnum) -1 t) ((1+ most-positive-fixnum) (1+ most-positive-fixnum) nil) ((1+ most-positive-fixnum) (1- most-negative-fixnum) t) (1 (ash most-negative-fixnum 1) nil) (29 most-negative-fixnum t) (30 (ash most-negative-fixnum 1) t) (31 (ash most-negative-fixnum 1) t) (64 (ash most-negative-fixnum 36) nil) (65 (ash most-negative-fixnum 36) t))) (destructuring-bind (index int result) x (assert (eq (eval `(logbitp ,index ,int)) result)))) ;;; off-by-1 type inference error for %DPB and %DEPOSIT-FIELD: (let ((f (compile nil '(lambda (b) (integer-length (dpb b (byte 4 28) -1005)))))) (assert (= (funcall f 1230070) 32))) (let ((f (compile nil '(lambda (b) (integer-length (deposit-field b (byte 4 28) -1005)))))) (assert (= (funcall f 1230070) 32))) ;;; type inference leading to an internal compiler error: (let ((f (compile nil '(lambda (x) (declare (type fixnum x)) (ldb (byte 0 0) x))))) (assert (= (funcall f 1) 0)) (assert (= (funcall f most-positive-fixnum) 0)) (assert (= (funcall f -1) 0))) ;;; Alpha bignum arithmetic bug: (assert (= (* 966082078641 419216044685) 404997107848943140073085)) ;;; Alpha smallnum arithmetic bug: (assert (= (ash -129876 -1026) -1)) ;;; Alpha middlenum (yes, really! Affecting numbers between 2^32 and ;;; 2^64 :) arithmetic bug (let ((fn (compile nil '(LAMBDA (A B C D) (DECLARE (TYPE (INTEGER -1621 -513) A) (TYPE (INTEGER -3 34163) B) (TYPE (INTEGER -9485132993 81272960) C) (TYPE (INTEGER -255340814 519943) D) (IGNORABLE A B C D) (OPTIMIZE (SPEED 3) (SAFETY 1) (DEBUG 1))) (TRUNCATE C (MIN -100 4149605)))))) (assert (= (funcall fn -1332 5864 -6963328729 -43789079) 69633287))) ;;; Here's another fantastic Alpha backend bug: the code to load ;;; immediate 64-bit constants into a register was wrong. (let ((fn (compile nil '(LAMBDA (A B C D) (DECLARE (TYPE (INTEGER -3563 2733564) A) (TYPE (INTEGER -548947 7159) B) (TYPE (INTEGER -19 0) C) (TYPE (INTEGER -2546009 0) D) (IGNORABLE A B C D) (OPTIMIZE (SPEED 3) (SAFETY 1) (DEBUG 1))) (CASE A ((89 125 16) (ASH A (MIN 18 -706))) (T (DPB -3 (BYTE 30 30) -1))))))) (assert (= (funcall fn 1227072 -529823 -18 -792831) -2147483649))) ;;; ASH of a negative bignum by a bignum count would erroneously ;;; return 0 prior to sbcl-0.8.4.4 (assert (= (ash (1- most-negative-fixnum) (1- most-negative-fixnum)) -1)) ;;; Whoops. Too much optimization in division operators for 0 ;;; divisor. (macrolet ((frob (name) `(let ((fn (compile nil '(lambda (x) (declare (optimize speed) (fixnum x)) (,name x 0))))) (assert (raises-error? (funcall fn 1) division-by-zero))))) (frob mod) (frob truncate) (frob rem) (frob /) (frob floor) (frob ceiling))