2009-03-25 Craig Howland <howland@LGSInnovations.com>

	* libc/include/math.h:  (llround, llroundf): Declare.
	* libm/common/s_llround.c: New file, implementing llround().
	* libm/common/sf_llround.c: New file, implementing llroundf().
	* libm/common/sf_lround.c: Remove spurious cast in _DOUBLE_IS_32BITS
	version of function.
	* libm/common/sf_lrint.c: Ditto.
	* libm/common/sf_logb.c:  Corrected return for subnormal argument
	by replacing existing function with a version created from sf_ilogb.c.
	* libm/common/s_logb.c: Ditto, except starting point s_ilogb.c.  Also
	added documentation for logb() and logbf().
	* libm/common/s_signbit.c:  Add signbit() documentation.
	* libm/common/s_log2.c: Update return values to match what w_log2.c has,
	since log2 uses log(); add note about being derived instead of direct.
	* libm/common/sf_fma.c: Add casts to attempt to get correct results,
	as well as comments pointing out problems with the implementation.
	* libm/common/s_fma.c: Add fma() and fmaf() documentation.
	* libm/common/sf_remquo.c: Incorrect quotient returns for large values
	corrected by discarding existing function and replacing with Sun
	verion, with some enhancements.
	* libm/common/s_remquo.c: Ditto.  Add remquo() and remquof()
	documentation.
	* libm/common/s_fmax.c: Add fmax() and fmaxf() documentation.
	* libm/common/s_fmin.c: Add fmin() and fminf() documentation.
	* libm/common/s_fdim.c: Return NAN for NAN arg, add fdim() and fdimf()
	documentation.
	* libm/common/sf_fdim.c: Return NAN for NAN arg, HUGE_VALF for inf arg.
	* libm/common/s_trunc.c: Add trunc() and truncf() documentation.
	* libm/common/s_rint.c: Add rint() and rintf() documentation.
	* libm/common/s_round.c: Add round() and roundf() documentation.
	* libm/common/s_scalbn.c: Add scalbln() and scalblnf() documentation.
	* libm/common/s_infinity.c: Add infinity() and infinityf()
	documentation.
	* libm/common/s_lround.c: Add lround(), lroundf(), llround(), and
	llroundf() documentation.
	* libm/common/s_lrint.c: Add lrint(), lrintf(), llrint(), and llrintf()
	documentation.
	* libm/common/isgreater.c: New file for documenting math.h function-like
	macros isgreater(), isgreaterequal(), isless(), islessequal(),
	islessgreater(), and isunordered().
	* libm/common/s_isnan.c: Add documentation for function-like macros
	fpclassify(), isfinite(), isinf(), isnan(), and isnormal().
	* libm/common/s_nearbyint.c: Add nearbyint() and nearbyintf()
	documentation.
	* libm/common/Makefile.am: Add s_llround.c (src); sf_llround.c (fsrc);
	s_fdim.def, s_fma.def, s_fmax.def, s_fmin.def,
	s_logb.def, s_lrint.def, s_lround.def, s_nearbyint.def, s_remquo.def,
        s_rint.def, s_round.def, s_signbit.def, s_trunc.def, and
        isgreater.def (chobj);
	re-name all existing chew files (chobj) to match source file base
	names (put in underscores), delete all special targets for chew files
	(leaving all to be generated by rule).
	* libm/common/Makefile.in: regenerate.
	* libm/math/w_exp2.c: Add "base 2" to documentation description (and
	delete TRAD_SYNOPSIS).
	* libm/math/w_gamma.c: Add tgamma() and tgammaf() documentation, along
	with some history behind the function names.
	* libm/math/math.tex: Add includes for newly-added documentation (see
	.def additions to common/Makefile.am and math/Makefile.am in this
	ChangeLog list), adjusted existing .def file names to match source file
	base names (added underscores); add mention of HUGE_VALF; rename
	"Version of library" section to "Error Handling" and add some text
	about floating-point exception; added section "Standards Compliance And
	Portability".
	* libm/math/Makefile.am: Add w_exp2.def (chobj);
	re-name all existing chew files (chobj) to match source file base
	names, delete all special targets for chew files (leaving all to be
	generated by rule).
	* libm/math/Makefile.in: regenerated
	* doc/makedoc.c: Change silent ignoring of commands < 5 characters
	to a failure when reading macro file for commands < 4 characters;
	add -v (verbose) option for printing some debugging information;
	get rid of spurious translation of "@*" to "*" (no source files used @*,
	so no existing doc pages were affected); clean up some compiler
	warnings.
	* doc/doc.str: add BUGS and SEEALSO sections (to match texi2pod.pl
	which has them); Remove ITEM command (redundant with makedoc built-in
	"o", not used in any present source file so nothing is lost, anyway).
	* HOWTO: New file to hold information for maintainers regarding how
	to do things.  Initial sections on documentation and ELIX levels.

1 files changed, 43 insertions, 10 deletions

diff --git a/newlib/libm/math/w_gamma.c b/newlib/libm/math/w_gamma.c
index fad40496d..3717f53e5 100644
--- a/newlib/libm/math/w_gamma.c
+++ b/newlib/libm/math/w_gamma.c
@@ -12,11 +12,20 @@
  *
  */
 
+/* BUG:  FIXME?
+     According to Linux man pages for tgamma, lgamma, and gamma, the gamma
+function was originally defined in BSD as implemented here--the log of the gamma
+function.  BSD 4.3 changed the name to lgamma, apparently removing gamma.  BSD
+4.4 re-introduced the gamma name with the more intuitive, without logarithm,
+plain gamma function.  The C99 standard apparently wanted to avoid a problem
+with the poorly-named earlier gamma and used tgamma when adding a plain
+gamma function.
+     So the current gamma is matching an old, bad definition, and not
+matching a newer, better definition.  */
 /*
 FUNCTION
-        <<gamma>>, <<gammaf>>, <<lgamma>>, <<lgammaf>>, <<gamma_r>>,
-	<<gammaf_r>>, <<lgamma_r>>, <<lgammaf_r>>---logarithmic gamma
-	function
+        <<gamma>>, <<gammaf>>, <<lgamma>>, <<lgammaf>>, <<gamma_r>>, <<gammaf_r>>, <<lgamma_r>>, <<lgammaf_r>>, <<tgamma>>, and <<tgammaf>>--logarithmic and plain gamma functions
+
 INDEX
 gamma
 INDEX
@@ -33,6 +42,10 @@ INDEX
 lgamma_r
 INDEX
 lgammaf_r
+INDEX
+tgamma
+INDEX
+tgammaf
 
 ANSI_SYNOPSIS
 #include <math.h>
@@ -44,6 +57,8 @@ double gamma_r(double <[x]>, int *<[signgamp]>);
 float gammaf_r(float <[x]>, int *<[signgamp]>);
 double lgamma_r(double <[x]>, int *<[signgamp]>);
 float lgammaf_r(float <[x]>, int *<[signgamp]>);
+double tgamma(double <[x]>);
+float tgammaf(float <[x]>);
 
 TRAD_SYNOPSIS
 #include <math.h>
@@ -67,15 +82,19 @@ int <[signgamp]>;
 float lgammaf_r(<[x]>, <[signgamp]>)
 float <[x]>;
 int <[signgamp]>;
+double tgamma(<[x]>)
+double <[x]>;
+float tgammaf(<[x]>)
+float <[x]>;
 
 DESCRIPTION
-<<gamma>> calculates 
+<<gamma>> calculates
 @tex
-$\mit ln\bigl(\Gamma(x)\bigr)$, 
+$\mit ln\bigl(\Gamma(x)\bigr)$,
 @end tex
 the natural logarithm of the gamma function of <[x]>.  The gamma function
 (<<exp(gamma(<[x]>))>>) is a generalization of factorial, and retains
-the property that  
+the property that
 @ifnottex
 <<exp(gamma(N))>> is equivalent to <<N*exp(gamma(N-1))>>.
 @end ifnottex
@@ -83,13 +102,13 @@ the property that
 $\mit \Gamma(N)\equiv N\times\Gamma(N-1)$.
 @end tex
 Accordingly, the results of the gamma function itself grow very
-quickly.  <<gamma>> is defined as 
+quickly.  <<gamma>> is defined as
 @tex
 $\mit ln\bigl(\Gamma(x)\bigr)$ rather than simply $\mit \Gamma(x)$
 @end tex
 @ifnottex
 the natural log of the gamma function, rather than the gamma function
-itself, 
+itself,
 @end ifnottex
 to extend the useful range of results representable.
 
@@ -113,8 +132,17 @@ variable <<signgam>> is not used.  These functions may be used for
 reentrant calls (but they will still set the global variable <<errno>>
 if an error occurs).
 
+<<tgamma>> and <<tgammaf>> are the "true gamma" functions, returning
+@tex
+$\mit \Gamma(x)$,
+@end tex
+the gamma function of <[x]>--without a logarithm.
+(They are apparently so named because of the prior existence of the old,
+poorly-named <<gamma>> functions which returned the log of gamma up
+through BSD 4.2.)
+
 RETURNS
-Normally, the computed result is returned.  
+Normally, the computed result is returned.
 
 When <[x]> is a nonpositive integer, <<gamma>> returns <<HUGE_VAL>>
 and <<errno>> is set to <<EDOM>>.  If the result overflows, <<gamma>>
@@ -123,7 +151,12 @@ returns <<HUGE_VAL>> and <<errno>> is set to <<ERANGE>>.
 You can modify this error treatment using <<matherr>>.
 
 PORTABILITY
-Neither <<gamma>> nor <<gammaf>> is ANSI C.  */
+Neither <<gamma>> nor <<gammaf>> is ANSI C.  It is better not to use either
+of these; use <<lgamma>> or <<tgamma>> instead.@*
+<<lgamma>>, <<lgammaf>>, <<tgamma>>, and <<tgammaf>> are nominally C standard
+in terms of the base return values, although the <<matherr>> error-handling
+is not standard, nor is the <[signgam]> global for <<lgamma>>.
+*/
 
 /* double gamma(double x)
  * Return the logarithm of the Gamma function of x.