Raymond Toy pushed to branch rtoy-setexception-inexact at cmucl / cmucl

Commits: b9e3a511 by Raymond Toy at 2015-12-24T09:29:08Z Use setexception to raise the inexact exception for tanh.

Note that original code didn't actually signal inexact probably because the compiler constant-folded one - tiny to one.

- - - - -

2 changed files:

- src/lisp/s_tanh.c - tests/fdlibm.lisp

Changes:

===================================== src/lisp/s_tanh.c ===================================== --- a/src/lisp/s_tanh.c +++ b/src/lisp/s_tanh.c @@ -78,7 +78,9 @@ static double one=1.0, two=2.0, tiny = 1.0e-300; } /* |x| > 22, return +-1 */ } else { - z = one - tiny; /* raised inexact flag */ + /* Always raise inexact flag */ + fdlibm_setexception(x, FDLIBM_INEXACT); + z = one - tiny; } return (jx>=0)? z: -z; }

===================================== tests/fdlibm.lisp ===================================== --- a/tests/fdlibm.lisp +++ b/tests/fdlibm.lisp @@ -88,7 +88,14 @@ (assert-error 'floating-point-invalid-operation (kernel:%tanh *snan*)) (kernel::with-float-traps-masked (:invalid) - (assert-true (ext:float-nan-p (kernel:%tanh *snan*))))) + (assert-true (ext:float-nan-p (kernel:%tanh *snan*)))) + ;; tanh(x) = +/- 1 for |x| > 22, raising inexact, always. + (let ((x 22.1d0)) + (with-inexact-exception-enabled + ;; This must throw an inexact exception for non-zero x even + ;; though the result is exactly x. + (assert-error 'floating-point-inexact + (kernel:%tanh x)))))

(define-test %acosh.exceptions (:tag :fdlibm)

View it on GitLab: https://gitlab.common-lisp.net/cmucl/cmucl/commit/b9e3a5113c1c08e5785fc36866...