The recently added new math code inlines error handling instead of using
error handling wrappers around __ieee754* internal symbols, and thus the
__ieee754* symbols are no longer provided.
However __ieee754_expf and __ieee754_logf are used in the implementation
of a number of other math functions. These symbols are safe to redirect
to the external expf and logf symbols, because those names are always
reserved when single precision math functions are reserved and the
additional error handling code is either not reached or there will be
an error in the final result that will override an internal spurious
errno setting.
For consistency all of __ieee754_expf, __ieee754_logf and __ieee754_powf
are redirected using a macro.
Based on code from https://github.com/ARM-software/optimized-routines/
This patch adds a highly optimized generic implementation of expf,
exp2f, logf, log2f and powf. The new functions are not only
faster (6x for powf!), but are also smaller and more accurate.
In order to achieve this, the algorithm uses double precision
arithmetic for accuracy, avoids divisions and uses small table
lookups to minimize the polynomials. Special cases are handled
inline to avoid the unnecessary overhead of wrapper functions and
set errno to POSIX requirements.
The new functions are added under newlib/libm/common, but the old
implementations are kept (in newlib/libm/math) for non-IEEE or
pre-C99 systems. Targets can enable the new math code by defining
__OBSOLETE_MATH_DEFAULT to 0 in newlib/libc/include/machine/ieeefp.h,
users can override the default by defining __OBSOLETE_MATH.
Currently the new code is enabled for AArch64 and AArch32 with VFP.
Targets with a single precision FPU may still prefer the old
implementation.
libm.a size changes:
arm: -1692
arm/thumb/v7-a/nofp: -878
arm/thumb/v7-a+fp/hard: -864
arm/thumb/v7-a+fp/softfp: -908
aarch64: -1476
previous commit 4c90db7bc8 introduced
a compile time error because libm/common/s_infconst.c used the remove
__fmath, __dmath, and __ldmath union types.
Since this is very old, and unused for a very long time, just drop the
file and thus the __infinity constants entirely.
Exception: Cygwin exports __infinity from the beginning. There's a very,
VERY low probability that any existing executable or lib still uses this
constant, but we just keep it in for backward compat, nevertheless.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
__builtin_isinf_sign doesn't reflect the correct return value for NaN
to emulate finite function. Use __builtin_isfinite instead whichg is available
since GCC 4.4 just as __builtin_isinf_sign.
* libm/common/sl_finite.c (finitel): Use __builtin_isfinite.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
I think these are accidental omissions, as these source files are listed to be
chewed by makedoc, but the result is not included by any texinfo source file.
Future work: Nothing in libc/reent/ which is processed by makedoc is included by
reent.tex
2015-06-23 Jon Turney <jon.turney@dronecode.org.uk>
* libc/stdlib/stdlib.tex: Include itoa and utoa, and add to menu.
* libc/string/strings.tex: Include memrchr and rawmemchr, and add
to menu.
* libm/math/math.tex: Include exp10 and pow10, and add to menu.
* libm/common/s_exp10.c: Improve one-line description.
* libm/common/s_exp10.c: Ditto.
Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
2015-06-23 Jon Turney <jon.turney@dronecode.org.uk>
* libc/stdlib/llabs.c: Mark up parameter name in ANSI_SYNOPSIS.
* libc/time/tzset.c: Add and mark up parameter in SYNOPSIS.
* libm/common/s_nan.c: Ditto.
Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
compiler warnings found this way.
* libc/stdio/freopen.c (_freopen_r): Fix bug setting _flags.
* libc/include/stdio.h (_rename): Define when building newlib.
* libc/include/sys/signal.h (_kill): Ditto.
* libc/include/sys/stat.h (_mkdir): Ditto.
* libc/include/sys/time.h (_gettimeofday): Ditto.
* libc/include/sys/times.h (_times): Ditto.
* libc/include/sys/wait.h (_wait): Ditto.
* libc/locale/lmessages.c (empty): Don't define for Cygwin.
* libc/locale/lmonetary.c (cnv): Ditto.
* libc/locale/nl_langinfo.c (nl_langinfo): Ditto for variable s.
* libc/posix/collate.c: Throughout cast to avoid compiler warning.
* libc/posix/engine.c (matcher): Initialize dp to avoid compiler
warning.
* libc/posix/glob.c: Disable on Cygwin. Explain why.
* libc/posix/regcomp.c: Fix "uninitialized" compiler warnings.
(dissect): Deliberately silence gcc compiler warning. Add comment to
explain why.
* libc/posix/wordexp.c (wordexp): Remove num_bytes variable since result
is never used.
* libc/posix/popen.c (popen): Ditto for variable last.
* libc/reent/mkdirr.c: Include sys/stat.h.
* libc/reent/renamer.c: Include stdio.h.
* libc/search/hash.c: Throughout use underscored variants of the stat
function family.
(init_hash): Add missing definition for the __USE_INTERNAL_STAT64 case.
* libc/search/hash_bigkey.c (__big_insert): Add parenthesis to avoid
compiler warning.
* libc/search/hash_page.c (overflow_page): Initalize freep to NULL to
avoid compiler warning.
* libc/stdio/asiprintf.c (_asiprintf_r): Cast unsigned char * to char *
to avoid compiler warning.
(asiprintf): Ditto.
* libc/stdio/asprintf.c (_asprintf_r): Ditto.
(asprintf): Ditto.
* libc/stdio/vasiprintf.c (_vasiprintf_r): Ditto.
* libc/stdio/vasprintf.c (_vasprintf_r): Ditto.
* libc/stdio/mktemp.c (_gettemp): Cast to unsigned char in call to
isdigit to avoid compiler warning.
* libc/stdio/vfprintf.c (_VFPRINTF_R): Initialize variables used for
grouping to avoid compiler warning. Only define and set nseps and
nrepeats if they are really used.
* libc/stdio/vfwprintf.c (_VFWPRINTF_R): Ditto. Only define state if
it is really used.
* libc/stdio/vfscanf.c (u_char): Revert to be defined as unsigned char.
(__SVFSCANF_R): Cast fmt in call to __mbtowc.
* libc/stdlib/mbtowc_r.c (JIS_state_table): Disable when building
Cygwin.
(JIS_action_table): Ditto.
* libc/stdlib/wctomb_r.c (__utf8_wctomb): Add parenthesis to avoid
compiler warning.
* libc/string/strcasestr.c: Deliberately silence gcc compiler warning.
Add comment to explain why.
* libc/time/strptime.c (strptime): Cast to unsigned char in calls to
isspace to avoid compiler warning.
* libm/math/e_atan2.c (__ieee754_atan2): Add parenthesis to avoid
compiler warning.
* libm/math/e_exp.c (__ieee754_exp): Initialize k to 0 to avoid
compiler warning. Drop setting it to 0 later.
* libm/math/ef_exp.c (__ieee754_expf): Ditto.
* libm/math/e_pow.c (__ieee754_pow): Add braces to avoid compiler
warning.
* libm/math/ef_pow.c (__ieee754_powf): Ditto.
* libm/math/er_lgamma.c (__ieee754_lgamma_r): Initialize nadj to 0 to
avoid compiler warning.
* libm/math/erf_lgamma.c (__ieee754_lgammaf_r): Ditto.
* libm/math/e_rem_pio2.c (__ieee754_rem_pio2): Ditto for variable z.
* libm/common/sf_round.c (roundf): Remove signbit variable since result
is never used.
* libm/common/s_log2.c: Change from using M_LOG2_E to M_LN2 define
(from math.h--the latter is POSIX, the former non-standard).
* libm/common/sf_log2.c: Ditto. Change cast for M_LN2 from float to
float_t (in case all math not done in float).
* libc/include/math.h: Ditto (same 2 things as sf_log2.c).
* libm/common/s_lrint.c (lrint): Annotate shift operations with
possible shift amount ranges, and use SAFE_RIGHT_SHIFT to avoid
undefined behaviour.
* libm/common/s_llrint.c (llrint): Likewise.
* libm/common/s_lround.c (lround): Correct some comments on ranges.
* libm/common/s_llround.c (llround): Likewise.
(SAFE_RIGHT_SHIFT): Likewise.
* libm/common/s_llround.c (llround): Annotate shift operations with
possible shift amount ranges, and use SAFE_RIGHT_SHIFT to avoid
undefined behaviour.
* libm/common/s_lround.c (lround): Likewise.
* libm/common/s_rint.c: Fix error when integral part had 18 bits and
fraction had bits set beyond first radix bit. Also, make 2-part
adjustment consistent with 1-part adjustment when adjusting fractional
bits.
* libm/common/sf_rint.c: Make fractional-bit adjustment consistent
with s_rint.c by setting 0b.01 instead of 0b.001.
* libm/common/s_ilogb.c: Adjust documentation to reflect new returns
(see next items) and that ilogb() and ilogbf() are C99/POSIX.
* libm/common/s_ilogb.c (ilogb): Use C99/POSIX FP_ILOGB0 and
FP_ILOGBNAN returns for 0 and NAN arguments, respectively, instead of
the prior -INT_MAX and INT_MAX. The FP_ILOGBx defines in math.h
presently match the prior hard-codes, so no functional change is
actually introduced. (Not at this time, nor planned, but the values
are permitted to be different, so subsequent edits of math.h could
possibly cause a functional change.)
* libm/common/sf_ilogb.c (ilogbf): Ditto.
* configure.in: Add configuration test for long double type existing
and set flag _HAVE_LONG_DOUBLE if true. Fix INIT_ARRAY (.init_array)
and _LDBL_EQ_DBL tests to not link so that will work with
cross-compilers.
* configure: Regenerated.
* Makefile.in: Ditto.
* newlib.hin: Add _HAVE_LONG_DOUBLE flag.
* libc/include/math.h: Change non-builtin defines for HUGE_VAL,
HUGE_VALF, and HUGE_VALL to be constant expressions. Add definitions
for the non-builtin case for INFINITY and NAN. Gate HUGE_VALL and
union __ldmath definitions with (new) _HAVE_LONG_DOUBLE.
*libm/common/s_infconst.c: Change definitions to use values from
float.h instead of non-so-portable integer forms. Mark as being
deprecated (because now removed from math.h, are not used anywhere
in Newlib, itself).
* configure.in: Add configuration test for long double equals dbl
and set flag _LDBL_EQ_DBL if true.
* configure: Regenerated.
* newlib.hin: Add _LDBL_EQ_DBL flag.
* libc/include/math.h: Use _LDBL_EQ_DBL flag instead of
_HAVE_LDBL_MATH.
* libc/include/stdlib.h: Use _LDBL_EQ_DBL flag instead of
_HAVE_LDBL_STDLIB.
* libc/common/local.h: Remove _LDBL_EQ_DBL flag setting.
* libc/stdlib/local.h: Ditto.
* 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.
Szabolcs Nagy
Corinna Vinschen
Jon Turney
Yaakov Selkowitz
Jeff Johnston
Nick Clifton
Joel Sherrill
Dave Korn
Steve Ellcey