From 8e26469445309da362b68da4167428a782c9daaa Mon Sep 17 00:00:00 2001
From: David Schultz <das@FreeBSD.org>
Date: Fri, 14 Jan 2005 23:28:28 +0000
Subject: [PATCH] Remove numerous references to VAX floating-point and the
 setting of errno, replacing them with a discussion of IEEE exceptions where
 appropriate.  Cross-reference fenv(3) whenever exceptions are mentioned.

---
 lib/msun/man/acos.3   | 15 ++++---------
 lib/msun/man/acosh.3  | 16 ++++----------
 lib/msun/man/asin.3   | 17 +++++----------
 lib/msun/man/atan2.3  | 20 ++++-------------
 lib/msun/man/atanh.3  | 21 ++++++------------
 lib/msun/man/cosh.3   | 14 +-----------
 lib/msun/man/exp.3    | 50 +++++++++----------------------------------
 lib/msun/man/hypot.3  | 11 +++-------
 lib/msun/man/j0.3     | 18 +---------------
 lib/msun/man/lgamma.3 |  9 +-------
 lib/msun/man/sinh.3   | 15 +------------
 lib/msun/man/sqrt.3   | 42 +++---------------------------------
 12 files changed, 44 insertions(+), 204 deletions(-)

diff --git a/lib/msun/man/acos.3 b/lib/msun/man/acos.3
index 6004f32d4afe..a08230a890fe 100644
--- a/lib/msun/man/acos.3
+++ b/lib/msun/man/acos.3
@@ -32,7 +32,7 @@
 .\"     from: @(#)acos.3	5.1 (Berkeley) 5/2/91
 .\" $FreeBSD$
 .\"
-.Dd May 2, 1991
+.Dd January 14, 2005
 .Dt ACOS 3
 .Os
 .Sh NAME
@@ -66,27 +66,20 @@ and the
 functions return the arc cosine in the range
 .Bq 0 , \*(Pi
 radians.
-On the
-.Tn VAX
-and
-.Tn Tahoe ,
-if:
+If:
 .Bd -unfilled -offset indent
 .Pf \&| Ns Ar x Ns \&| > 1 ,
 .Ed
 .Pp
 .Fn acos x
-sets the global variable
-.Va errno
-to
-.Er EDOM
-and a reserved operand fault is generated.
+raises an invalid exception and returns an \*(Na.
 .Sh SEE ALSO
 .Xr asin 3 ,
 .Xr atan 3 ,
 .Xr atan2 3 ,
 .Xr cos 3 ,
 .Xr cosh 3 ,
+.Xr fenv 3 ,
 .Xr math 3 ,
 .Xr sin 3 ,
 .Xr sinh 3 ,
diff --git a/lib/msun/man/acosh.3 b/lib/msun/man/acosh.3
index 2eb82d13dadc..b1339013889d 100644
--- a/lib/msun/man/acosh.3
+++ b/lib/msun/man/acosh.3
@@ -32,7 +32,7 @@
 .\"     from: @(#)acosh.3	5.2 (Berkeley) 5/6/91
 .\" $FreeBSD$
 .\"
-.Dd May 6, 1991
+.Dd January 14, 2005
 .Dt ACOSH 3
 .Os
 .Sh NAME
@@ -66,22 +66,14 @@ and the
 functions
 return the inverse hyperbolic cosine of
 .Ar x .
-On the
-.Tn VAX
-and
-.Tn Tahoe ,
-if the argument is less than one
+If the argument is less than 1,
 .Fn acosh
-sets the global variable
-.Va errno
-to
-.Er EDOM
-and
-causes a reserved operand fault.
+raises an invalid exception and returns an \*(Na.
 .Sh SEE ALSO
 .Xr asinh 3 ,
 .Xr atanh 3 ,
 .Xr exp 3 ,
+.Xr fenv 3 ,
 .Xr math 3
 .Sh HISTORY
 The
diff --git a/lib/msun/man/asin.3 b/lib/msun/man/asin.3
index f3ec7ac71208..e33623d74db3 100644
--- a/lib/msun/man/asin.3
+++ b/lib/msun/man/asin.3
@@ -32,7 +32,7 @@
 .\"     from: @(#)asin.3	5.1 (Berkeley) 5/2/91
 .\" $FreeBSD$
 .\"
-.Dd May 2, 1991
+.Dd January 14, 2005
 .Dt ASIN 3
 .Os
 .Sh NAME
@@ -68,27 +68,20 @@ functions return the arc sine in the range
 .Bq -\*(Pi/2 , +\*(Pi/2
 .Ek
 radians.
-On the
-.Tn VAX ,
-and Tahoe,
-if:
+If:
 .Bd -unfilled -offset indent
 .Pf \&| Ns Ar x Ns \&| > 1
 .Ed
 .Pp
-the
-global variable
-.Va errno
-is set to
-.Er EDOM
-and
-a reserved operand fault generated.
+.Fn asin x
+raises an invalid exception and returns an \*(Na.
 .Sh SEE ALSO
 .Xr acos 3 ,
 .Xr atan 3 ,
 .Xr atan2 3 ,
 .Xr cos 3 ,
 .Xr cosh 3 ,
+.Xr fenv 3 ,
 .Xr math 3 ,
 .Xr sin 3 ,
 .Xr sinh 3 ,
diff --git a/lib/msun/man/atan2.3 b/lib/msun/man/atan2.3
index f951812bab0c..3f564975cd3f 100644
--- a/lib/msun/man/atan2.3
+++ b/lib/msun/man/atan2.3
@@ -32,7 +32,7 @@
 .\"     from: @(#)atan2.3	5.1 (Berkeley) 5/2/91
 .\" $FreeBSD$
 .\"
-.Dd May 2, 1991
+.Dd January 14, 2005
 .Dt ATAN2 3
 .Os
 .Sh NAME
@@ -69,16 +69,7 @@ in the range
 .Bq \&- Ns \*(Pi , \&+ Ns \*(Pi
 .Ek
 radians.
-If both
-.Fa x
-and
-.Fa y
-are zero, the global variable
-.Va errno
-is set to
-.Er EDOM .
-On the
-.Tn VAX :
+Here are some of the special cases:
 .Bl -column atan_(y,x)_:=____  sign(y)_(Pi_atan2(Xy_xX))___
 .It Fn atan2 y x No := Ta
 .Fn atan y/x Ta
@@ -105,9 +96,7 @@ The function
 .Fn atan2
 defines "if x > 0,"
 .Fn atan2 0 0
-= 0 on a
-.Tn VAX
-despite that previously
+= 0 despite that previously
 .Fn atan2 0 0
 may have generated an error message.
 The reasons for assigning a value to
@@ -144,8 +133,7 @@ is mapped to
 .if n \
 (r=0,theta=0)
 .if t \
-(r=0,\(*h=0)
-on a VAX.
+(r=0,\(*h=0) .
 In general, conversions to polar coordinates
 should be computed thus:
 .Bd -unfilled -offset indent
diff --git a/lib/msun/man/atanh.3 b/lib/msun/man/atanh.3
index cd9f276ce19f..10575c7cc4a9 100644
--- a/lib/msun/man/atanh.3
+++ b/lib/msun/man/atanh.3
@@ -32,7 +32,7 @@
 .\"     from: @(#)atanh.3	5.2 (Berkeley) 5/6/91
 .\" $FreeBSD$
 .\"
-.Dd May 6, 1991
+.Dd January 14, 2005
 .Dt ATANH 3
 .Os
 .Sh NAME
@@ -67,23 +67,16 @@ functions
 return the inverse hyperbolic tangent of
 .Ar x
 if successful.
-On the
-.Tn VAX
-and
-.Tn Tahoe ,
-if the argument has absolute value
-bigger than or equal to 1,
-.Fn atanh
-sets the global variable
-.Va errno
-to
-.Er EDOM
-and
-a reserved operand fault is generated.
+If the argument has absolute value 1, a divide-by-zero exception
+is raised and an infinity is returned.
+If
+.Ar |x|
+> 1, an invalid exception is raised an an \*(Na is returned.
 .Sh SEE ALSO
 .Xr acosh 3 ,
 .Xr asinh 3 ,
 .Xr exp 3 ,
+.Xr fenv 3 ,
 .Xr math 3
 .Sh HISTORY
 The
diff --git a/lib/msun/man/cosh.3 b/lib/msun/man/cosh.3
index d2b28249b8a0..74744d4e335a 100644
--- a/lib/msun/man/cosh.3
+++ b/lib/msun/man/cosh.3
@@ -32,7 +32,7 @@
 .\"     from: @(#)cosh.3	5.1 (Berkeley) 5/2/91
 .\" $FreeBSD$
 .\"
-.Dd May 2, 1991
+.Dd January 14, 2005
 .Dt COSH 3
 .Os
 .Sh NAME
@@ -54,18 +54,6 @@ and the
 .Fn coshf
 functions compute the hyperbolic cosine of
 .Fa x .
-.Sh RETURN VALUES
-The
-.Fn cosh
-and the
-.Fn coshf
-functions return the hyperbolic cosine unless the magnitude
-of
-.Fa x
-is too large; in this event, the global variable
-.Va errno
-is set to
-.Er ERANGE .
 .Sh SEE ALSO
 .Xr acos 3 ,
 .Xr asin 3 ,
diff --git a/lib/msun/man/exp.3 b/lib/msun/man/exp.3
index 62e9e3e1b301..326af5804139 100644
--- a/lib/msun/man/exp.3
+++ b/lib/msun/man/exp.3
@@ -32,7 +32,7 @@
 .\"     from: @(#)exp.3	6.12 (Berkeley) 7/31/91
 .\" $FreeBSD$
 .\"
-.Dd July 31, 1991
+.Dd January 14, 2005
 .Dt EXP 3
 .Os
 .Sh NAME
@@ -182,49 +182,18 @@ is exact until it is bigger than 2**56 on a
 These functions will return the appropriate computation unless an error
 occurs or an argument is out of range.
 The functions
-.Fn exp ,
-.Fn expm1 ,
-.Fn pow
-detect if the computed value will overflow,
-set the global variable
-.Va errno
-to
-.Er ERANGE
-and cause a reserved operand fault on a
-.Tn VAX
-or
-.Tn Tahoe .
-The functions
 .Fn pow x y
-checks to see if
+and
+.Fn powf x y
+raise an invalid exception and return an \*(Na if
 .Fa x
 < 0 and
 .Fa y
-is not an integer, in the event this is true,
-the global variable
-.Va errno
-is set to
-.Er EDOM
-and on the
-.Tn VAX
-and
-.Tn Tahoe
-generate a reserved operand fault.
-On a
-.Tn VAX
-and
-.Tn Tahoe ,
-.Va errno
-is set to
-.Er EDOM
-and the reserved operand is returned
-by log unless
-.Fa x
-> 0, by
-.Fn log1p
-unless
-.Fa x
-> \-1.
+is not an integer.
+An attempt to take the logarithm of \*(Pm0 will result in
+a divide-by-zero exception, and an infinity will be returned.
+An attempt to take the logarithm of a negative number will
+result in an invalid exception, and an \*(Na will be generated.
 .Sh NOTES
 The functions exp(x)\-1 and log(1+x) are called
 expm1 and logp1 in
@@ -304,6 +273,7 @@ then \*(Na**0 = 1 too because x**0 = 1 for all finite
 and infinite x, i.e., independently of x.
 .El
 .Sh SEE ALSO
+.Xr fenv 3 ,
 .Xr math 3
 .Sh HISTORY
 A
diff --git a/lib/msun/man/hypot.3 b/lib/msun/man/hypot.3
index 312457878d1f..4843e4418373 100644
--- a/lib/msun/man/hypot.3
+++ b/lib/msun/man/hypot.3
@@ -32,7 +32,7 @@
 .\"     from: @(#)hypot.3	6.7 (Berkeley) 5/6/91
 .\" $FreeBSD$
 .\"
-.Dd May 6, 1991
+.Dd January 14, 2005
 .Dt HYPOT 3
 .Os
 .Sh NAME
@@ -98,13 +98,8 @@ and
 .Fn hypot "\*(Na" "v"
 are \*(Na for all
 .Em finite
-.Fa v ;
-with "reserved operand" in place of "\*(Na", the
-same is true on a
-.Tn VAX .
-But programmers on machines other than a
-.Tn VAX
-(if has no \*(If)
+.Fa v .
+But programmers
 might be surprised at first to discover that
 .Fn hypot "\(+-\*(If" "\*(Na"
 = +\*(If.
diff --git a/lib/msun/man/j0.3 b/lib/msun/man/j0.3
index 006119fcbaa7..2d8081084cdd 100644
--- a/lib/msun/man/j0.3
+++ b/lib/msun/man/j0.3
@@ -32,7 +32,7 @@
 .\"     from: @(#)j0.3	6.7 (Berkeley) 4/19/91
 .\" $FreeBSD$
 .\"
-.Dd April 19, 1991
+.Dd January 14, 2005
 .Dt J0 3
 .Os
 .Sh NAME
@@ -134,22 +134,6 @@ value
 .Sh RETURN VALUES
 If these functions are successful,
 the computed value is returned.
-On the
-.Tn VAX
-and
-.Tn Tahoe
-architectures,
-for the Bessel functions of the second kind,
-a negative
-or zero
-.Fa x
-value
-results in an error; the global
-variable
-.Va errno
-is set to
-.Er EDOM
-and a reserve operand fault is generated.
 .Sh SEE ALSO
 .Xr math 3
 .Sh HISTORY
diff --git a/lib/msun/man/lgamma.3 b/lib/msun/man/lgamma.3
index e950908ce6f4..085de97140ea 100644
--- a/lib/msun/man/lgamma.3
+++ b/lib/msun/man/lgamma.3
@@ -32,7 +32,7 @@
 .\"     from: @(#)lgamma.3	6.6 (Berkeley) 12/3/92
 .\" $FreeBSD$
 .\"
-.Dd December 3, 1992
+.Dd January 14, 2005
 .Dt LGAMMA 3
 .Os
 .Sh NAME
@@ -149,13 +149,6 @@ and
 return appropriate values unless an argument is out of range.
 Overflow will occur for sufficiently large positive values, and
 non-positive integers.
-On the
-.Tn VAX ,
-the reserved operator is returned,
-and
-.Va errno
-is set to
-.Er ERANGE .
 For large non-integer negative values,
 .Fn tgamma
 will underflow.
diff --git a/lib/msun/man/sinh.3 b/lib/msun/man/sinh.3
index ce3808cbf001..f7e69955c011 100644
--- a/lib/msun/man/sinh.3
+++ b/lib/msun/man/sinh.3
@@ -31,7 +31,7 @@
 .\"
 .\"	from: @(#)sinh.3	6.6 (Berkeley) 4/19/91
 .\" $FreeBSD$
-.Dd April 19, 1991
+.Dd January 14, 2005
 .Dt SINH 3
 .Os
 .Sh NAME
@@ -53,19 +53,6 @@ and the
 .Fn sinhf
 functions compute the hyperbolic sine of
 .Fa x .
-.Sh RETURN VALUES
-The
-.Fn sinh
-and the
-.Fn sinhf
-functions return the hyperbolic sine value unless
-the magnitude
-of
-.Fa x
-is too large; in this event, the global variable
-.Va errno
-is set to
-.Er ERANGE .
 .Sh SEE ALSO
 .Xr acos 3 ,
 .Xr asin 3 ,
diff --git a/lib/msun/man/sqrt.3 b/lib/msun/man/sqrt.3
index d4abf01f00a7..99399008f0b5 100644
--- a/lib/msun/man/sqrt.3
+++ b/lib/msun/man/sqrt.3
@@ -80,49 +80,13 @@ and the
 .Fn sqrtf
 functions return the requested square root
 unless an error occurs.
-On the
-.Tn VAX
-or
-.Tn Tahoe
-processor an attempt to take the
+An attempt to take the
 .Fn sqrt
 of negative
 .Fa x
-causes an error; in this event,
-the global variable
-.Va errno
-is set to
-.Er EDOM
-and a reserved operand fault is generated.
-.Sh ERROR (due to Roundoff etc.)
-The
-.Fn cbrt
-function
-is accurate to within 0.7
-.Em ulps .
-.Pp
-The
-.Fn sqrt
-function on a
-.Tn VAX
-is accurate to within 0.501
-.Em ulps .
-Sqrt on a machine that conforms to
-.Tn IEEE
-754 is correctly rounded
-in accordance with the rounding mode in force; the error is less than
-half an
-.Em ulp
-in the default mode (round\-to\-nearest).
-An
-.Em ulp
-is one
-.Em U Ns nit
-in the
-.Em L Ns ast
-.Em P Ns lace
-carried.
+raises an invalid exception and causes an \*(Na to be returned.
 .Sh SEE ALSO
+.Xr fenv 3 ,
 .Xr math 3
 .Sh STANDARDS
 The