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at 2026-02-02T20:51:58-08:00

Check for infinite arg for sin, cos, tan

fdlibm signals overflow for infinite args for sin, cos, and tan.  Do
the same for core-math.

Also add test that NaN is silently returned from sin, cos, and tan are
given a quiet NaN.  That's what fdlibm does.

@@ -43,6 +43,11 @@ double
  lisp_sin(double x)
+ {
  #ifdef FEATURE_CORE_MATH
 +    /* Signals invalid if x is infinite */
 +    if (isinf(x)) {
 +	return fdlibm_setexception(x, FDLIBM_INVALID);
 +    }
++
      return cr_sin(x);
  #else
      return fdlibm_sin(x);
@@ -53,6 +58,11 @@ double
  lisp_cos(double x)
+ {
  #ifdef FEATURE_CORE_MATH
 +    /* Signals invalid if x is infinite */
 +    if (isinf(x)) {
 +	return fdlibm_setexception(x, FDLIBM_INVALID);
 +    }
++
      return cr_cos(x);
  #else
      return fdlibm_cos(x);
@@ -63,6 +73,11 @@ double
  lisp_tan(double x)
+ {
  #ifdef FEATURE_CORE_MATH
 +    /* Signals invalid if x is infinite */
 +    if (isinf(x)) {
 +	return fdlibm_setexception(x, FDLIBM_INVALID);
 +    }
++
      return cr_tan(x);
  #else
      return fdlibm_tan(x);

@@ -214,7 +214,6 @@
    (ext:with-float-traps-masked (:overflow)
      (assert-equal ext:double-float-positive-infinity
  		  (kernel:%exp 710d0)))
 -  #-core-math
    (let ((modes (ext:get-floating-point-modes)))
      (unwind-protect
  	 (progn
@@ -671,6 +670,14 @@
  (define-test %cos.exceptions
      (:tag :fdlibm)
 +  ;; cos(inf) signals invalid operation
 +  (assert-error 'floating-point-invalid-operation
 +		(kernel:%cos ext:double-float-positive-infinity))
 +  (assert-error 'floating-point-invalid-operation
 +		(kernel:%cos ext:double-float-negative-infinity))
 +  ;; cos(nan) is NaN
 +  (assert-true (ext:float-nan-p (kernel:%cos *qnan*)))
++
    ;; cos(x) = 1 for |x| < 2^-27.  Signal inexact unless x = 0
    (let ((x (scale-float 1d0 -28))
  	(x0 0d0))
@@ -686,6 +693,14 @@
  (define-test %sin.exceptions
      (:tag :fdlibm)
 +  ;; sin(inf) signals invalid operation
 +  (assert-error 'floating-point-invalid-operation
 +		(kernel:%sin ext:double-float-positive-infinity))
 +  (assert-error 'floating-point-invalid-operation
 +		(kernel:%sin ext:double-float-negative-infinity))
 +  ;; sin(nan) is NaN
 +  (assert-true (ext:float-nan-p (kernel:%sin *qnan*)))
++
    ;; sin(x) = x for |x| < 2^-27.  Signal inexact unless x = 0
    (let ((x (scale-float 1d0 -28))
  	(x0 0d0))
@@ -701,6 +716,14 @@
  (define-test %tan.exceptions
      (:tag :fdlibm)
 +  ;; tan(inf) signals invalid operation
 +  (assert-error 'floating-point-invalid-operation
 +		(kernel:%tan ext:double-float-positive-infinity))
 +  (assert-error 'floating-point-invalid-operation
 +		(kernel:%tan ext:double-float-negative-infinity))
 +  ;; tan(nan) is NaN
 +  (assert-true (ext:float-nan-p (kernel:%sin *qnan*)))
++
    ;; tan(x) = x for |x| < 2^-28.  Signal inexact unless x = 0
    (let ((x (scale-float 1d0 -29))
  	(x0 0d0))

Raymond Toy pushed to branch issue-468-core-math-signals at cmucl / cmucl

Commits:

2 changed files:

Changes: