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diff --git a/lib/msun/man/math.3 b/lib/msun/man/math.3
index 553154b..0b622b4 100644
--- a/lib/msun/man/math.3
+++ b/lib/msun/man/math.3
@@ -200,418 +200,9 @@ in this section may not produce a result that is correctly rounded.
 In general, an unbounded number of digits of a value taken by a
 transcendental function may be needed to determine the correctly rounded
 result.
-.Sh NOTES
-Virtually all modern floating-point units attempt to support
-IEEE Standard 754 for Binary Floating-Point Arithmetic.
-This standard does not cover particular routines in the math library
-except for the few documented in
-.Xr ieee 3 ;
-it primarily defines representations of numbers and abstract
-properties of arithmetic operations relating to precision, rounding,
-and exceptional cases, as described below.
-.Ss IEEE STANDARD 754 Floating-Point Arithmetic
-.\" XXX mention single- and extended-/quad- precisions
-Radix: Binary.
-.Pp
-.Bl -column "" -compact
-Overflow and underflow:
-.El
-.Bd -ragged -offset indent -compact
-Overflow goes by default to a signed \*(If.
-Underflow is
-.Em gradual .
-.Ed
-.Pp
-Zero is represented ambiguously as +0 or \-0.
-.Bd -ragged -offset indent -compact
-Its sign transforms correctly through multiplication or
-division, and is preserved by addition of zeros
-with like signs; but x\-x yields +0 for every
-finite x.
-The only operations that reveal zero's
-sign are division by zero and
-.Fn copysign x \(+-0 .
-In particular, comparison (x > y, x \(>= y, etc.)\&
-cannot be affected by the sign of zero; but if
-finite x = y then \*(If = 1/(x\-y) \(!= \-1/(y\-x) = \-\*(If.
-.Ed
-.Pp
-Infinity is signed.
-.Bd -ragged -offset indent -compact
-It persists when added to itself
-or to any finite number.
-Its sign transforms
-correctly through multiplication and division, and
-(finite)/\(+-\*(If\0=\0\(+-0
-(nonzero)/0 = \(+-\*(If.
-But
-\*(If\-\*(If, \*(If\(**0 and \*(If/\*(If
-are, like 0/0 and sqrt(\-3),
-invalid operations that produce \*(Na. ...
-.Ed
-.Pp
-Reserved operands (\*(Nas):
-.Bd -ragged -offset indent -compact
-An \*(Na is
-.Em ( N Ns ot Em a N Ns umber ) .
-Some \*(Nas, called Signaling \*(Nas, trap any floating-point operation
-performed upon them; they are used to mark missing
-or uninitialized values, or nonexistent elements
-of arrays.
-The rest are Quiet \*(Nas; they are
-the default results of Invalid Operations, and
-propagate through subsequent arithmetic operations.
-If x \(!= x then x is \*(Na; every other predicate
-(x > y, x = y, x < y, ...) is FALSE if \*(Na is involved.
-.Ed
-.Pp
-Rounding:
-.Bd -ragged -offset indent -compact
-Every algebraic operation (+, \-, \(**, /,
-\(sr)
-is rounded by default to within half an
-.Em ulp ,
-and when the rounding error is exactly half an
-.Em ulp
-then
-the rounded value's least significant bit is zero.
-(An
-.Em ulp
-is one
-.Em U Ns nit
-in the
-.Em L Ns ast
-.Em P Ns lace . )
-This kind of rounding is usually the best kind,
-sometimes provably so; for instance, for every
-x = 1.0, 2.0, 3.0, 4.0, ..., 2.0**52, we find
-(x/3.0)\(**3.0 == x and (x/10.0)\(**10.0 == x and ...
-despite that both the quotients and the products
-have been rounded.
-Only rounding like IEEE 754 can do that.
-But no single kind of rounding can be
-proved best for every circumstance, so IEEE 754
-provides rounding towards zero or towards
-+\*(If or towards \-\*(If
-at the programmer's option.
-.Ed
-.Pp
-Exceptions:
-.Bd -ragged -offset indent -compact
-IEEE 754 recognizes five kinds of floating-point exceptions,
-listed below in declining order of probable importance.
-.Bl -column -offset indent "Invalid Operation" "Gradual Underflow"
-.Em "Exception	Default Result"
-Invalid Operation	\*(Na, or FALSE
-Overflow	\(+-\*(If
-Divide by Zero	\(+-\*(If
-Underflow	Gradual Underflow
-Inexact	Rounded value
-.El
-.Pp
-NOTE: An Exception is not an Error unless handled
-badly.
-What makes a class of exceptions exceptional
-is that no single default response can be satisfactory
-in every instance.
-On the other hand, if a default
-response will serve most instances satisfactorily,
-the unsatisfactory instances cannot justify aborting
-computation every time the exception occurs.
-.Ed
-.Ss Data Formats
-Single-precision:
-.Bd -ragged -offset indent -compact
-Type name:
-.Vt float
-.Pp
-Wordsize: 32 bits.
-.Pp
-Precision: 24 significant bits,
-roughly like 7 significant decimals.
-.Bd -ragged -offset indent -compact
-If x and x' are consecutive positive single-precision
-numbers (they differ by 1
-.Em ulp ) ,
-then
-.Bd -ragged -compact
-5.9e\-08 < 0.5**24 < (x'\-x)/x \(<= 0.5**23 < 1.2e\-07.
-.Ed
-.Ed
-.Pp
-.Bl -column "XXX" -compact
-Range:	Overflow threshold  = 2.0**128 = 3.4e38
-	Underflow threshold = 0.5**126 = 1.2e\-38
-.El
-.Bd -ragged -offset indent -compact
-Underflowed results round to the nearest
-integer multiple of 0.5**149 = 1.4e\-45.
-.Ed
-.Ed
-.Pp
-Double-precision:
-.Bd -ragged -offset indent -compact
-Type name:
-.Vt double
-.Bd -ragged -offset indent -compact
-On some architectures,
-.Vt long double
-is the the same as
-.Vt double .
-.Ed
-.Pp
-Wordsize: 64 bits.
-.Pp
-Precision: 53 significant bits,
-roughly like 16 significant decimals.
-.Bd -ragged -offset indent -compact
-If x and x' are consecutive positive double-precision
-numbers (they differ by 1
-.Em ulp ) ,
-then
-.Bd -ragged -compact
-1.1e\-16 < 0.5**53 < (x'\-x)/x \(<= 0.5**52 < 2.3e\-16.
-.Ed
-.Ed
-.Pp
-.Bl -column "XXX" -compact
-Range:	Overflow threshold  = 2.0**1024 = 1.8e308
-	Underflow threshold = 0.5**1022 = 2.2e\-308
-.El
-.Bd -ragged -offset indent -compact
-Underflowed results round to the nearest
-integer multiple of 0.5**1074 = 4.9e\-324.
-.Ed
-.Ed
-.Pp
-Extended-precision:
-.Bd -ragged -offset indent -compact
-Type name:
-.Vt long double
-(when supported by the hardware)
-.Pp
-Wordsize: 96 bits.
-.Pp
-Precision: 64 significant bits,
-roughly like 19 significant decimals.
-.Bd -ragged -offset indent -compact
-If x and x' are consecutive positive double-precision
-numbers (they differ by 1
-.Em ulp ) ,
-then
-.Bd -ragged -compact
-1.0e\-19 < 0.5**63 < (x'\-x)/x \(<= 0.5**62 < 2.2e\-19.
-.Ed
-.Ed
-.Pp
-.Bl -column "XXX" -compact
-Range:	Overflow threshold  = 2.0**16384 = 1.2e4932
-	Underflow threshold = 0.5**16382 = 3.4e\-4932
-.El
-.Bd -ragged -offset indent -compact
-Underflowed results round to the nearest
-integer multiple of 0.5**16451 = 5.7e\-4953.
-.Ed
-.Ed
-.Pp
-Quad-extended-precision:
-.Bd -ragged -offset indent -compact
-Type name:
-.Vt long double
-(when supported by the hardware)
-.Pp
-Wordsize: 128 bits.
-.Pp
-Precision: 113 significant bits,
-roughly like 34 significant decimals.
-.Bd -ragged -offset indent -compact
-If x and x' are consecutive positive double-precision
-numbers (they differ by 1
-.Em ulp ) ,
-then
-.Bd -ragged -compact
-9.6e\-35 < 0.5**113 < (x'\-x)/x \(<= 0.5**112 < 2.0e\-34.
-.Ed
-.Ed
-.Pp
-.Bl -column "XXX" -compact
-Range:	Overflow threshold  = 2.0**16384 = 1.2e4932
-	Underflow threshold = 0.5**16382 = 3.4e\-4932
-.El
-.Bd -ragged -offset indent -compact
-Underflowed results round to the nearest
-integer multiple of 0.5**16494 = 6.5e\-4966.
-.Ed
-.Ed
-.Ss Additional Information Regarding Exceptions
-.Pp
-For each kind of floating-point exception, IEEE 754
-provides a Flag that is raised each time its exception
-is signaled, and stays raised until the program resets
-it.
-Programs may also test, save and restore a flag.
-Thus, IEEE 754 provides three ways by which programs
-may cope with exceptions for which the default result
-might be unsatisfactory:
-.Bl -enum
-.It
-Test for a condition that might cause an exception
-later, and branch to avoid the exception.
-.It
-Test a flag to see whether an exception has occurred
-since the program last reset its flag.
-.It
-Test a result to see whether it is a value that only
-an exception could have produced.
-.Pp
-CAUTION: The only reliable ways to discover
-whether Underflow has occurred are to test whether
-products or quotients lie closer to zero than the
-underflow threshold, or to test the Underflow
-flag.
-(Sums and differences cannot underflow in
-IEEE 754; if x \(!= y then x\-y is correct to
-full precision and certainly nonzero regardless of
-how tiny it may be.)
-Products and quotients that
-underflow gradually can lose accuracy gradually
-without vanishing, so comparing them with zero
-(as one might on a VAX) will not reveal the loss.
-Fortunately, if a gradually underflowed value is
-destined to be added to something bigger than the
-underflow threshold, as is almost always the case,
-digits lost to gradual underflow will not be missed
-because they would have been rounded off anyway.
-So gradual underflows are usually
-.Em provably
-ignorable.
-The same cannot be said of underflows flushed to 0.
-.El
-.Pp
-At the option of an implementor conforming to IEEE 754,
-other ways to cope with exceptions may be provided:
-.Bl -enum
-.It
-ABORT.
-This mechanism classifies an exception in
-advance as an incident to be handled by means
-traditionally associated with error-handling
-statements like "ON ERROR GO TO ...".
-Different
-languages offer different forms of this statement,
-but most share the following characteristics:
-.Bl -dash
-.It
-No means is provided to substitute a value for
-the offending operation's result and resume
-computation from what may be the middle of an
-expression.
-An exceptional result is abandoned.
-.It
-In a subprogram that lacks an error-handling
-statement, an exception causes the subprogram to
-abort within whatever program called it, and so
-on back up the chain of calling subprograms until
-an error-handling statement is encountered or the
-whole task is aborted and memory is dumped.
-.El
-.It
-STOP.
-This mechanism, requiring an interactive
-debugging environment, is more for the programmer
-than the program.
-It classifies an exception in
-advance as a symptom of a programmer's error; the
-exception suspends execution as near as it can to
-the offending operation so that the programmer can
-look around to see how it happened.
-Quite often
-the first several exceptions turn out to be quite
-unexceptionable, so the programmer ought ideally
-to be able to resume execution after each one as if
-execution had not been stopped.
-.It
-\&... Other ways lie beyond the scope of this document.
-.El
-.Pp
-Ideally, each
-elementary function should act as if it were indivisible, or
-atomic, in the sense that ...
-.Bl -enum
-.It
-No exception should be signaled that is not deserved by
-the data supplied to that function.
-.It
-Any exception signaled should be identified with that
-function rather than with one of its subroutines.
-.It
-The internal behavior of an atomic function should not
-be disrupted when a calling program changes from
-one to another of the five or so ways of handling
-exceptions listed above, although the definition
-of the function may be correlated intentionally
-with exception handling.
-.El
-.Pp
-The functions in
-.Nm libm
-are only approximately atomic.
-They signal no inappropriate exception except possibly ...
-.Bl -tag -width indent -offset indent -compact
-.It Xo
-Over/Underflow
-.Xc
-when a result, if properly computed, might have lain barely within range, and
-.It Xo
-Inexact in
-.Fn cabs ,
-.Fn cbrt ,
-.Fn hypot ,
-.Fn log10
-and
-.Fn pow
-.Xc
-when it happens to be exact, thanks to fortuitous cancellation of errors.
-.El
-Otherwise, ...
-.Bl -tag -width indent -offset indent -compact
-.It Xo
-Invalid Operation is signaled only when
-.Xc
-any result but \*(Na would probably be misleading.
-.It Xo
-Overflow is signaled only when
-.Xc
-the exact result would be finite but beyond the overflow threshold.
-.It Xo
-Divide-by-Zero is signaled only when
-.Xc
-a function takes exactly infinite values at finite operands.
-.It Xo
-Underflow is signaled only when
-.Xc
-the exact result would be nonzero but tinier than the underflow threshold.
-.It Xo
-Inexact is signaled only when
-.Xc
-greater range or precision would be needed to represent the exact result.
-.El
 .Sh SEE ALSO
 .Xr fenv 3 ,
 .Xr ieee 3
-.Pp
-An explanation of IEEE 754 and its proposed extension p854
-was published in the IEEE magazine MICRO in August 1984 under
-the title "A Proposed Radix- and Word-length-independent
-Standard for Floating-point Arithmetic" by
-.An "W. J. Cody"
-et al.
-The manuals for Pascal, C and BASIC on the Apple Macintosh
-document the features of IEEE 754 pretty well.
-Articles in the IEEE magazine COMPUTER vol.\& 14 no.\& 3 (Mar.\&
-1981), and in the ACM SIGNUM Newsletter Special Issue of
-Oct.\& 1979, may be helpful although they pertain to
-superseded drafts of the standard.
 .Sh HISTORY
 A math library with many of the present functions appeared in
 .At v7 .