include/math.h has a mechanism to redirect internal calls to various
libm functions, that can often be inlined by the compiler, to call
non-exported __* names for those functions in the case when the calls
aren't inlined, with the redirection being disabled when
NO_MATH_REDIRECT. Add fma to the functions to which this mechanism is
applied.
At present, libm-internal fma calls (generally to __builtin_fma*
functions) are only done when it's known the call will be inlined,
with alternative code not relying on an fma operation being used in
the caller otherwise. This patch is in preparation for adding the TS
18661 / C2X narrowing fma functions to glibc; it will be natural for
the narrowing function implementations to call the underlying fma
functions unconditionally, with this either being inlined or resulting
in an __fma* call. (Using two levels of round-to-odd computation like
that, in the case where there isn't an fma hardware instruction, isn't
optimal but is certainly a lot simpler for the initial implementation
than writing different narrowing fma implementations for all the
various pairs of formats.)
Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by the patch (using
<https://sourceware.org/pipermail/libc-alpha/2021-September/130991.html>
to fix installed library stripping in build-many-glibcs.py). Also
tested for x86_64.
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date. Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.
Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions. These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.
The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively. These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:
https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dchttps://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
This patch converts libm function implementations in math/ from using
weak_alias to using libm_alias_float to define public function names,
in cases where it would be appropriate to define _Float32 aliases for
those functions as well. expf and exp2f are omitted from this patch,
given the in-progress patches that would change their symbol
versioning arrangements (at a later stage it will be necessary to add
macros that can be used for functions with such symbol versioning
arrangements - which will apply to lgammaf as well - but for the
initial patches in this area I'm just dealing with easy cases, and any
symbol versioning changes to these functions while the work is in
progress can effectively just undo the libm_alias_* changes as regards
those functions).
Tested for x86_64. Also tested with build-many-glibcs.py that
installed stripped shared libraries are unchanged by the patch.
* math/s_fmaf.c: Include <libm-alias-float.h>.
(fmaf): Define using libm_alias_float.
* math/w_acosf_compat.c: Include <libm-alias-float.h>.
(acosf): Define using libm_alias_float.
* math/w_acoshf_compat.c: Include <libm-alias-float.h>.
(acoshf): Define using libm_alias_float.
* math/w_asinf_compat.c: Include <libm-alias-float.h>.
(asinf): Define using libm_alias_float.
* math/w_atan2f_compat.c: Include <libm-alias-float.h>.
(atan2f): Define using libm_alias_float.
* math/w_atanhf_compat.c: Include <libm-alias-float.h>.
(atanhf): Define using libm_alias_float.
* math/w_coshf_compat.c: Include <libm-alias-float.h>.
(coshf): Define using libm_alias_float.
* math/w_exp10f_compat.c: Include <libm-alias-float.h>.
(exp10f): Define using libm_alias_float.
* math/w_fmodf_compat.c: Include <libm-alias-float.h>.
(fmodf): Define using libm_alias_float.
* math/w_hypotf_compat.c: Include <libm-alias-float.h>.
(hypotf): Define using libm_alias_float.
* math/w_j0f_compat.c: Include <libm-alias-float.h>.
(j0f): Define using libm_alias_float.
(y0f): Likewise.
* math/w_j1f_compat.c: Include <libm-alias-float.h>.
(j1f): Define using libm_alias_float.
(y1f): Likewise.
* math/w_jnf_compat.c: Include <libm-alias-float.h>.
(jnf): Define using libm_alias_float.
(ynf): Likewise.
* math/w_log10f_compat.c: Include <libm-alias-float.h>.
(log10f): Define using libm_alias_float.
* math/w_log2f_compat.c: Include <libm-alias-float.h>.
(log2f): Define using libm_alias_float.
* math/w_logf_compat.c: Include <libm-alias-float.h>.
(logf): Define using libm_alias_float.
* math/w_powf_compat.c: Include <libm-alias-float.h>.
(powf): Define using libm_alias_float.
* math/w_remainderf_compat.c: Include <libm-alias-float.h>.
(remainderf): Define using libm_alias_float.
* math/w_sinhf_compat.c: Include <libm-alias-float.h>.
(sinhf): Define using libm_alias_float.
* math/w_sqrtf_compat.c: Include <libm-alias-float.h>.
(sqrtf): Define using libm_alias_float.
* math/w_tgammaf_compat.c: Include <libm-alias-float.h>.
(tgammaf): Define using libm_alias_float.
