4
0
mirror of git://sourceware.org/git/newlib-cygwin.git synced 2025-01-23 15:40:14 +08:00

415 Commits

Author SHA1 Message Date
Mike Frysinger
b9346cee1a newlib: switch to standard AC_PROG_CC
Now that we use AC_NO_EXECUTABLES, and we require a recent version of
autoconf, we don't need to define our own copies of these macros.  So
switch to the standard AC_PROG_CC.
2022-02-08 19:09:26 -05:00
Mike Frysinger
9b50254377 newlib: move AC_NO_EXECUTABLES logic up to common code
This logic was added to libc & libm to get it working again after some
reworks in the CPP handling, but now that that's settled, let's move
this to the common newlib configure logic.  This will make it easier
to consolidate all the configure calls into the top-level newlib dir.

This does create a lot of noise in the generate scripts, but that's
because of the ordering of the calls, not because of correctness. We
will try to draw that back down in follow up commits as we modernize
the toolchain calls in here.
2022-02-08 19:09:26 -05:00
Mike Frysinger
953ba1e6d1 newlib: simplify nds32 automake checks
This code is a bit more convoluted than it needs to be.  GPR_SOURCES
is never set to anything, and the automake checks use negative logic
to add the SP & DP source files to dedicated variables that are only
expanded once.  Get rid of the unused variable, use normal boolean
logic, and collapse the source settings into a single variable.
2022-02-08 19:06:15 -05:00
Mike Frysinger
24b1e4b942 newlib: drop shared documentation rules
Now that the top-level makefile handles these, don't need to copy
these into every single subdir.
2022-02-05 00:18:01 -05:00
Mike Frysinger
6026ef29d8 newlib: move man page generation into top-level build
This allows building the libc & libm pages in parallel, and drops
the duplication in the subdirs with the chew/chapter settings.

The unused rules in Makefile.shared are left in place to minimize
noise in the change.
2022-02-05 00:17:54 -05:00
Mike Frysinger
3365bd2f7a newlib: libm: move manual into top-level build
This doesn't migrate all the docs, just the libm's manual (pdf/info).
This is to show the basic form of migrating the chew files.
2022-02-04 19:39:05 -05:00
Mike Frysinger
041dd7ff26 newlib: add AC_CACHE_CHECK sugar around preprocessor checks
This isn't strictly necessary, but it makes for much clearer logs as
to what the target is doing, and provides cache vars for anyone who
wants to force the test a different way, and it lets the build cache
its own results when rerunning config.status.
2022-02-01 18:15:51 -05:00
Mike Frysinger
4b0e66093c newlib: fix preprocessor checks
Restore the call to AC_NO_EXECUTABLES -- I naively assumed in commit
2e9aa5f56cc26a411014a7f788423c670cfb5646 ("newlib: update preprocessor
configure checks") that checking for a preprocessor would not involve
linking code.  Unfortunately, autoconf will implicitly check that the
compiler "works" before allowing it to be used, and that involves a
link test, and that fails because newlib provides the C library which
is needed to pass a link test.

There is some code in NEWLIB_CONFIGURE specifically to help mitigate
these, but it's not kicking in here for some reason, so let's just add
the AC_NO_EXECUTABLES call back until we can unwind that custom logic.

Additionally, we have to call AC_PROG_CPP explicitly.  This was being
invoked later on, but only in the use_libtool=yes codepath, and that
is almost never enabled.
2022-01-31 22:21:17 -05:00
Mike Frysinger
fc0bd2eb03 newlib: use abs_newlib_basedir for -I paths
When we had configure scripts in subdirs, the newlib_basedir value
was computed relative to that, and it'd be the same when used in the
Makefile in the same dir.  With many subdir configure scripts removed,
the top-level configure & Makefile can't use the same relative path.
So switch the subdir Makefiles over to abs_newlib_basedir when they
use -I to find source headers.

Do this for all subdirs, even ones with configure scripts and where
newlib_basedir works.  This makes the code consistent, and avoids
surprises if the configure script is ever removed in the future as
part of merging to the higher level.

Some of the subdirs were using -I$(newlib_basedir)/../newlib/ for
some reason.  Collapse those too since newlib_basedir points to the
newlib source tree already.
2022-01-29 01:35:30 -05:00
Mike Frysinger
6444f108d9 newlib: export abs_newlib_basedir for all subdirs
When using the top-level configure script but subdir Makefiles, the
newlib_basedir value gets a bit out of sync: it's relative to where
configure lives, not where the Makefile lives.  Move the abs setting
from the top-level configure script into acinclude.m4 so we can rely
on it being available everywhere.  Although this commit doesn't use
it anywhere, just lays the groundwork.
2022-01-29 01:35:30 -05:00
Mike Frysinger
2339979934 newlib: libm: merge machine/ configure scripts up a level
The machine configure scripts are all effectively stub scripts that
pass the higher level options to its own makefile.  The only one doing
any custom tests was nds32.  The rest were all effectively the same as
the libm/ configure script.

So instead of recursively running configure in all of these subdirs,
generate their makefiles from the top-level configure.  For nds32,
deploy a pattern of including subdir logic via m4:
	m4_include([machine/nds32/acinclude.m4])

Even its set of checks are very small -- it does 2 preprocessor tests
and sets up 2 makefile conditionals.

Some of the generated machine makefiles have a bunch of extra stuff
added to them, but that's because they were inconsistent in their
configure libtool calls.  The top-level has it, so it exports some
new vars to the ones that weren't already.
2022-01-26 03:11:20 -05:00
Mike Frysinger
6ac043b192 newlib: libm: merge machine/ trampoline up a level
The machine/{configure,Makefile} files exist only to fan out to the
specific machine/$arch/ subdir.  We already have all that same info
in the libm/ dir itself, so by moving the recursive configure and
make calls into it, we can cut off this logic entirely and save the
overhead.

For arches that don't have a machine subdir, it means they can skip
the logic entirely.
2022-01-26 03:11:20 -05:00
Mike Frysinger
5420733ef3 newlib: libm: drop unused config.h.in file
Not sure how this snuck in.  It's never been used in libm/, so punt it.
2022-01-25 21:56:47 -05:00
Mike Frysinger
2e9aa5f56c newlib: update preprocessor configure checks
The nds32 & spu dirs are using compile tests to look for some
preprocessor defines, but we don't need to compile the code,
just preprocess it.  So switch to AC_PREPROC_IFELSE.

The sh dir is using a preprocessor test via grep, but let's
switch it to AC_PREPROC_IFELSE too to be consistent.

This should allow us to drop the uncommon AC_NO_EXECUTABLES call.
2022-01-23 22:35:21 -05:00
Mike Frysinger
f159663b08 newlib: stop clobbering LDFLAGS with non-standard $ldflags
It's unclear why this was added originally, but assuming it was needed
20 years ago, it shouldn't be explicitly required nowadays.  Current
versions of autotools already take care of exporting LDFLAGS to the
Makefile as needed (things are actually getting linked).  That's why
the configure diffs show LDFLAGS still here, but shifted to a diff
place in the output list.  A few dirs stop exporting LDFLAGS, but
that's because they don't do any linking, only compiling, so it's
correct.

As for the use of $ldflags instead of the standard $LDFLAGS, I can't
really explain that at all.  Just use the right name so users don't
have to dig into why their setting isn't respected, and then use a
non-standard name instead.  Adjust the testsuite to match.
2022-01-21 17:10:10 -05:00
Mike Frysinger
4317e0676a newlib: stop checking --enable-multilib in subdirs
None of the subdirs actually use the multilib arg, so include the
logic only in the top-level configure.
2022-01-21 17:10:10 -05:00
Mike Frysinger
6783cceb0a newlib: libm: switch to autoconf long double macro
Now that we require a recent version of autoconf, we can rely on this
macro working.  We shift the call in configure.ac down a little to
help keep the generated diff minimal -- there should be no functional
difference otherwise.  This is because the autoconf macros will call
a bunch of standard toolchain macros first, and arguably the current
code is incorrect in how it does its testing.
2022-01-19 18:51:04 -05:00
Mike Frysinger
6746e06043 newlib: avoid duplicate awk checks
Since AM_INIT_AUTOMAKE calls AC_PROG_AWK, and some configure.ac
scripts call it too, we end up testing for awk multiple times.  If
we change NEWLIB_CONFIGURE to require the macro instead, then it
makes sure it's always expanded, but only once.

While we're here, do the same thing with AC_PROG_INSTALL since it
is also called by AM_INIT_AUTOMAKE, although it doesn't currently
result in duplicate configure checks.
2022-01-18 19:25:18 -05:00
Mike Frysinger
3722489f1f newlib: merge old AC_LIBTOOL_WIN32_DLL macro into LT_INIT
The AC_LIBTOOL_WIN32_DLL macro has been deprecated for a while and code
should call LT_INIT with win32-dll instead.  Update the calls to match.

The generated code is noisy not because of substantial differences, but
because the order of some macros change (i.e. instead of calling AS and
then CC, CC is called first and then AS).
2022-01-18 19:15:44 -05:00
Mike Frysinger
fe591ba3f7 newlib: update libtool macro name
Replace old AM_PROG_LIBTOOL name with LT_INIT.  There's no change to
the generated files since they're aliases internally.
2022-01-18 19:15:44 -05:00
Mike Frysinger
71086e8b2d newlib: delete (most) redundant lib_a_CCASFLAGS=$(AM_CCASFLAGS)
Since automake already sets per-library CCASFLAGS to $(AM_CCASFLAGS)
by default, there's no need to explicitly set it here.

Many of these dirs don't have .S files in the first place, so the rule
doesn't even do anything.  That can easily be seen when Makefile.in has
no changes as a result.

For the dirs with .S files, the custom rules are the same as the pattern
.S.o rules, so this is a nice cleanup.

The only dir that was adding extra flags (newlib/libc/machine/mn10300/)
to the per-library setting can have it moved to the global AM_CCASFLAGS
since the subdir only has one target.  Although the setting just adds
extra debugging flags, so maybe it should be deleted in general.

There are a few dirs that we leave the redundant setting in place.  This
is to workaround an automake limitation in subdirs that support building
with & w/out libtool:
https://www.gnu.org/software/automake/manual/html_node/Objects-created-both-with-libtool-and-without.html
2022-01-18 19:12:02 -05:00
Mike Frysinger
20e3103471 newlib: update to automake-1.15
This matches what the other GNU toolchain projects have done already.
The generated diff in practice isn't terribly large.  This will allow
more use of subdir local.mk includes due to fixes & improvements that
came after the 1.11 release series.
2022-01-14 19:10:38 -05:00
Mike Frysinger
a100e80fc9 require autoconf-2.69 exactly
The newlib & libgloss dirs are already generated using autoconf-2.69.
To avoid merging new code and/or accidental regeneration using diff
versions, leverage config/override.m4 to pin to 2.69 exactly.  This
matches what gcc/binutils/gdb are already doing.

The README file already says to use autoconf-2.69.

To accomplish this, it's just as simple as adding -I flags to the
top-level config/ dir when running aclocal.  This is because the
override.m4 file overrides AC_INIT to first require the specific
autoconf version before calling the real AC_INIT.
2022-01-14 15:24:33 -05:00
Nick Alcock
5ab7dd14e1 libtool.m4: fix nm BSD flag detection
Libtool needs to get BSD-format (or MS-format) output out of the system
nm, so that it can scan generated object files for symbol names for
-export-symbols-regex support.  Some nms need specific flags to turn on
BSD-formatted output, so libtool checks for this in its AC_PATH_NM.
Unfortunately the code to do this has a pair of interlocking flaws:

 - it runs the test by doing an nm of /dev/null.  Some platforms
   reasonably refuse to do an nm on a device file, but before now this
   has only been worked around by assuming that the error message has a
   specific textual form emitted by Tru64 nm, and that getting this
   error means this is Tru64 nm and that nm -B would work to produce
   BSD-format output, even though the test never actually got anything
   but an error message out of nm -B.  This is fixable by nm'ing *nm
   itself* (since we necessarily have a path to it).

 - the test is entirely skipped if NM is set in the environment, on the
   grounds that the user has overridden the test: but the user cannot
   reasonably be expected to know that libtool wants not only nm but
   also flags forcing BSD-format output.  Worse yet, one such "user" is
   the top-level Cygnus configure script, which neither tests for
   nor specifies any BSD-format flags.  So platforms needing BSD-format
   flags always fail to set them when run in a Cygnus tree, breaking
   -export-symbols-regex on such platforms.  Libtool also needs to
   augment $LD on some platforms, but this is done unconditionally,
   augmenting whatever the user specified: the nm check should do the
   same.

   One wrinkle: if the user has overridden $NM, a path might have been
   provided: so we use the user-specified path if there was one, and
   otherwise do the path search as usual.  (If the nm specified doesn't
   work, this might lead to a few extra pointless path searches -- but
   the test is going to fail anyway, so that's not a problem.)

(Tested with NM unset, and set to nm, /usr/bin/nm, my-nm where my-nm is a
symlink to /usr/bin/nm on the PATH, and /not-on-the-path/my-nm where
*that* is a symlink to /usr/bin/nm.)

ChangeLog
2021-09-27  Nick Alcock  <nick.alcock@oracle.com>

	PR libctf/27967
	* libtool.m4 (LT_PATH_NM): Try BSDization flags with a user-provided
	NM, if there is one.  Run nm on itself, not on /dev/null, to avoid
	errors from nms that refuse to work on non-regular files.  Remove
	other workarounds for this problem.  Strip out blank lines from the
	nm output.
2022-01-12 08:49:10 -05:00
Nick Alcock
4fe13b8d95 libtool.m4: augment symcode for Solaris 11
This reports common symbols like GNU nm, via a type code of 'C'.

ChangeLog
2021-09-27  Nick Alcock  <nick.alcock@oracle.com>

	PR libctf/27967
	* libtool.m4 (lt_cv_sys_global_symbol_pipe): Augment symcode for
	Solaris 11.
2022-01-12 08:47:00 -05:00
Alexander von Gluck IV
8a563bfdd7 Add support for the haiku operating system. These are the os support patches we have been grooming and maintaining for quite a few years over on git.haiku-os.org. All of these architectures are working and most have been stable for quite some time. 2022-01-12 08:43:25 -05:00
H.J. Lu
88d86e5970 GCC: Check if AR works with --plugin and rc
AR from older binutils doesn't work with --plugin and rc:

[hjl@gnu-cfl-2 bin]$ touch foo.c
[hjl@gnu-cfl-2 bin]$ ar --plugin /usr/libexec/gcc/x86_64-redhat-linux/10/liblto_plugin.so rc libfoo.a foo.c
[hjl@gnu-cfl-2 bin]$ ./ar --plugin /usr/libexec/gcc/x86_64-redhat-linux/10/liblto_plugin.so rc libfoo.a foo.c
./ar: no operation specified
[hjl@gnu-cfl-2 bin]$ ./ar --version
GNU ar (Linux/GNU Binutils) 2.29.51.0.1.20180112
Copyright (C) 2018 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or (at your option) any later version.
This program has absolutely no warranty.
[hjl@gnu-cfl-2 bin]$

Check if AR works with --plugin and rc before passing --plugin to AR and
RANLIB.

	PR ld/27173
	* configure: Regenerated.
	* libtool.m4 (_LT_CMD_OLD_ARCHIVE): Check if AR works with
	--plugin and rc before enabling --plugin.

config/

	PR ld/27173
	* gcc-plugin.m4 (GCC_PLUGIN_OPTION): Check if AR works with
	--plugin and rc before enabling --plugin.

libiberty/

	PR ld/27173
	* configure: Regenerated.

zlib/

	PR ld/27173
	* configure: Regenerated.
2022-01-12 08:43:14 -05:00
H.J. Lu
d8d5dac0fe GCC: Pass --plugin to AR and RANLIB
Detect GCC LTO plugin.  Pass --plugin to AR and RANLIB to support LTO
build.

	* Makefile.tpl (AR): Add @AR_PLUGIN_OPTION@
	(RANLIB): Add @RANLIB_PLUGIN_OPTION@.
	* configure.ac: Include config/gcc-plugin.m4.
	AC_SUBST AR_PLUGIN_OPTION and RANLIB_PLUGIN_OPTION.
	* libtool.m4 (_LT_CMD_OLD_ARCHIVE): Pass --plugin to AR and
	RANLIB if possible.
	* Makefile.in: Regenerated.
	* configure: Likewise.

config/

	* gcc-plugin.m4 (GCC_PLUGIN_OPTION): New.

libiberty/

	* Makefile.in (AR): Add @AR_PLUGIN_OPTION@
	(RANLIB): Add @RANLIB_PLUGIN_OPTION@.
	(configure_deps): Depend on ../config/gcc-plugin.m4.
	* aclocal.m4: Include ../config/gcc-plugin.m4.
	* configure.ac: AC_SUBST AR_PLUGIN_OPTION and
	RANLIB_PLUGIN_OPTION.
	* configure: Regenerated.

zlib/

	* configure: Regenerated.
2022-01-12 08:43:05 -05:00
Samuel Thibault
4a3b4d50e3 libtool.m4: update GNU/Hurd test from upstream. In upstream libtool, 47a889a4ca20 ("Improve GNU/Hurd support.") fixed detection of shlibpath_overrides_runpath, thus avoiding unnecessary relink. This backports it.
.	* libtool.m4: Match gnu* along other GNU systems.

*/ChangeLog:

	* configure: Re-generate.
2022-01-12 07:19:46 -05:00
Mike Frysinger
8fc6b4b30e newlib: regen aclocal.m4 after autoconf update
The configure scripts were regenerated with 2.69 for the newlib-4.2.0
release in 484d2ebf8d825b28af47b8ee88cd845f1d2c7c6e, but the aclocal
files were not.  Do that now to avoid confusion between the two as to
which version of autoconf was used.
2022-01-12 07:01:18 -05:00
Mike Frysinger
54d77a0a56 newlib: use .texi with libc & libm manuals
Newer automake warns that .texinfo extensions are discouraged in favor
of .texi, so rename the manuals to match.
2022-01-07 15:54:10 -05:00
Mike Frysinger
ed20821a40 newlib: migrate from INCLUDES to AM_CPPFLAGS
Since automake deprecated the INCLUDES name in favor of AM_CPPFLAGS,
change all existing users over.  The generated code is the same since
the two variables have been used in the same exact places by design.

There are other cleanups to be done, but lets focus on just renaming
here so we can upgrade to a newer automake version w/out triggering
new warnings.
2022-01-05 20:29:53 -05:00
Jeff Johnston
484d2ebf8d Update newlib to 4.2.0 2021-12-31 12:46:13 -05:00
Jon Turney
bfcabeb876
newlib: Regenerate autotools files 2021-12-29 22:45:06 +00:00
Jon Turney
a4e734fcdb
newlib: Remove automake option 'cygnus'
The 'cygnus' option was removed from automake 1.13 in 2012, so the
presence of this option prevents that or a later version of automake
being used.

A check-list of the effects of '--cygnus' from the automake 1.12
documentation, and steps taken (where possible) to preserve those
effects (See also this thread [1] for discussion on that):

[1] https://lists.gnu.org/archive/html/bug-automake/2012-03/msg00048.html

1. The foreign strictness is implied.

Already present in AM_INIT_AUTOMAKE in newlib/acinclude.m4

2. The options no-installinfo, no-dependencies and no-dist are implied.

Already present in AM_INIT_AUTOMAKE in newlib/acinclude.m4

Future work: Remove no-dependencies and any explicit header dependencies,
and use automatic dependency tracking instead.  Are there explicit rules
which are now redundant to removing no-installinfo and no-dist?

3. The macro AM_MAINTAINER_MODE is required.

Already present in newlib/acinclude.m4

Note that maintainer-mode is still disabled by default.

4. Info files are always created in the build directory, and not in the
source directory.

This appears to be an error in the automake documentation describing
'--cygnus' [2]. newlib's info files are generated in the source
directory, and no special steps are needed to keep doing that.

[2] https://lists.gnu.org/archive/html/bug-automake/2012-04/msg00028.html

5. texinfo.tex is not required if a Texinfo source file is specified.
(The assumption is that the file will be supplied, but in a place that
automake cannot find.)

This effect is overriden by an explicit setting of the TEXINFO_TEX
variable (the directory part of which is fed into texi2X via the
TEXINPUTS environment variable).

6. Certain tools will be searched for in the build tree as well as in the
user's PATH. These tools are runtest, expect, makeinfo and texi2dvi.

For obscure automake reasons, this effect of '--cygnus' is not active
for makeinfo in newlib's configury.

However, there appears to be top-level configury which selects in-tree
runtest, expect and makeinfo, if present. So, if that works as it
appears, this effect is preserved. If not, this may cause problem if
anyone is building those tools in-tree.

This effect is not preserved for texi2dvi. This may cause problems if
anyone is building texinfo in-tree.

If needed, explicit checks for those tools looking in places relative to
$(top_srcdir)/../ as well as in PATH could be added.

7. The check target doesn't depend on all.

This effect is not preseved. The check target now depends on the all
target.

This concern seems somewhat academic given the current state of the
testsuite.

Also note that this doesn't touch libgloss.
2021-12-29 22:45:04 +00:00
Jon Turney
8e166351b3
newlib: Regenerate autotools files 2021-12-29 22:45:03 +00:00
Jon Turney
320510de2c
newlib: Make effects of 'cygnus' explicit
Add all the effects of 'cygnus' for which there exists an explicit way
to request that behaviour:

* Implied foreign strictness and options no-installinfo, no-dependencies
and no-dist are added to AM_INIT_AUTOMAKE in newlib/acinclude.m4.

* macro AM_MAINTAINER_MODE is added to newlib/acinclude.m4.

* For the implied TEXINFO_TEX of '$(top_srcdir)/../texinfo/texinfo.tex',
an explicit TEXINFO_TEX is always relative to $(srcdir), so write the
same pathname in that form.

This is to prepare for the removal of the automake option '--cygnus'.
2021-12-29 22:44:49 +00:00
Jon Turney
639cb7ec1a
newlib: Regenerate all autotools files
Regenerate all aclocal.m4, configure and Makefile.in files.
2021-12-09 21:41:35 +00:00
Takashi Yano
34876c05a5 frexpl: Support smaller long double of LDBL_MANT_DIG == 53.
- Currently, frexpl() supports only the following cases.
    1) LDBL_MANT_DIG == 64 or 113
    2) 'long double' is equivalent to 'double'
  This patch add support for LDBL_MANT_DIG == 53.
2021-12-03 19:14:03 +09:00
Jeff Johnston
8fa73a9f84 Modifying patch from: marian.buschsieweke@ovgu.de
The code accessing the floating point control/status register, namely

	#define	__cfc1(__fcsr)	__asm __volatile("cfc1 %0, $31" : "=r" (__fcsr)

does not compile with mips16. This changed the makefile to pass -mno-mips16 to avoid the following
compiler error:

	mips-mti-elf fails with "Error: unrecognized opcode `cfc1 $3,$31'"
2021-11-30 11:23:39 -05:00
Takashi Yano
48f6c59332 stdio: Fix issue of printing "%La" format with large exp part.
- Currently, printf("%La\n", 1e1000L) crashes with segv due to lack
  of frexpl() function. With this patch, frexpl() function has been
  implemented in libm to solve this issue.

Addresses: https://sourceware.org/pipermail/newlib/2021/018718.html
2021-11-29 22:51:16 +09:00
Mike Frysinger
59e83de0b1 libgloss/newlib: update configure.ac in Makefile.in files
The maintainer rules refer to configure.in directly, so update that
after renaming all the configure.ac files.
2021-11-06 14:14:49 -04:00
Mike Frysinger
920617998e libgloss/newlib: rename configure.in to configure.ac
The .in name has been deprecated for a long time in favor of .ac.
2021-09-13 10:14:37 -04:00
Corinna Vinschen
76c2c7a891 ldexp/ldexpf: avoid assembler warning
libm/machine/i386/f_ldexp.S:30: Warning: no instruction mnemonic suffix given and no register operands; using default for `fild'
libm/machine/i386/f_ldexpf.S:30: Warning: no instruction mnemonic suffix given and no register operands; using default for `fild'

fix this by adding the l mnemonic suffix

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2021-09-03 12:52:47 +02:00
Kito Cheng
ca7b4bd236 libm: Fixing overflow handling issue for scalbnf and scalbn
cc Aldy Hernandez <aldyh@redhat.com> and Andrew MacLeod <amacleod@redhat.com>,
they are author of new VRP analysis for GCC, just to make sure I didn't
mis-understanding or mis-interpreting anything on GCC site.

GCC 11 have better value range analysis, that give GCC more confidence
to perform more aggressive optimization, but it cause scalbn/scalbnf get
wrong result.

Using scalbn to demostrate what happened on GCC 11, see comments with VRP
prefix:

```c
double scalbn (double x, int n)
{
	/* VRP RESULT: n = [-INF, +INF] */
        __int32_t  k,hx,lx;
        ...
        k = (hx&0x7ff00000)>>20;
	/* VRP RESULT: k = [0, 2047] */
        if (k==0) {
	    /* VRP RESULT: k = 0 */
	    ...
	    k = ((hx&0x7ff00000)>>20) - 54;
            if (n< -50000) return tiny*x;       /*underflow*/
	    /* VRP RESULT: k = -54 */
	}
	/* VRP RESULT: k = [-54, 2047] */
        if (k==0x7ff) return x+x;               /* NaN or Inf */
	/* VRP RESULT: k = [-54, 2046] */
        k = k+n;
        if (k > 0x7fe) return huge*copysign(huge,x); /* overflow  */
	/* VRP RESULT: k = [-INF, 2046] */
	/* VRP RESULT: n = [-INF, 2100],
	   because k + n <= 0x7fe is false, so:
	   1. -INF < [-54, 2046] + n <= 0x7fe(2046) < INF
	   2. -INF < [-54, 2046] + n <= 2046 < INF
	   3. -INF < n <= 2046 - [-54, 2046] < INF
	   4. -INF < n <= [0, 2100] < INF
	   5. n = [-INF, 2100] */
        if (k > 0)                              /* normal result */
            {SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20)); return x;}
        if (k <= -54) {
	    /* VRP OPT: Evaluate n > 50000 as true...*/
            if (n > 50000)      /* in case integer overflow in n+k */
                return huge*copysign(huge,x);   /*overflow*/
            else return tiny*copysign(tiny,x);  /*underflow*/
	}
        k += 54;                                /* subnormal result */
        SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20));
        return x*twom54;
}
```

However give the input n = INT32_MAX, k = k+n will overflow, and then we
expect got `huge*copysign(huge,x)`, but new VRP optimization think
`n > 50000` is never be true, so optimize that into `tiny*copysign(tiny,x)`.

so the solution here is to moving the overflow handle logic before `k = k + n`.
2021-07-21 09:56:04 +02:00
Jeff Johnston
a9165ea07c Fix rounding issues with sqrt/sqrtf
- compiler is sometimes optimizing out the rounding check in
  e_sqrt.c and ef_sqrt.c which uses two constants to create
  an inexact operation
- there is a similar constant operation in s_tanh.c/sf_tanh.c
- make the one and tiny constants volatile to stop this
2021-06-04 14:42:58 -04:00
Ties Stuij
282445a10e fix some Arm FP routines not checking if floating point is enabled
A lot of the Arm FP routines check for the availability of floating point by way
of `(__ARM_FP & 0x4)`. However some do not. This patch remedies this.
2021-04-21 16:18:09 +01:00
David Macek
7078248485 fenv: fix up stub file comment, drop symlinks from description
also slightly fixed up formatting
2021-04-13 12:55:34 +02:00
Corinna Vinschen
cc19109af9 Cygwin: don't export _feinitialise from newlib
Use the more official fesetenv(FE_DFL_ENV) from _dll_crt0, thus
allowing to drop the _feinitialise declaration from fenv.h.

Provide a no-op _feinitialise in Cygwin as exportable symbol for really
old applications when _feinitialise was called from mainCRTStartup in
crt0.o.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2021-04-13 12:55:34 +02:00
Corinna Vinschen
3b22d72255 fenv: drop Cygwin-specific implementation in favor of newlib code
Drop the Cygwin-specific fenv.cc and fenv.h file and use the equivalent
newlib functionality now, so we have at least one example of a user for
this new mechanism.

fenv.c: allow _feinitialise to be called from Cygwin startup code

fenv.h: add declarations for fegetprec and fesetprec for Cygwin only.
        Fix a comment.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2021-04-13 12:55:34 +02:00