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Author SHA1 Message Date
Lasse Collin
f644473a21 liblzma: Add fast CRC64 for 32/64-bit x86 using SSSE3 + SSE4.1 + CLMUL.
It also works on E2K as it supports these intrinsics.

On x86-64 runtime detection is used so the code keeps working on
older processors too. A CLMUL-only build can be done by using
-msse4.1 -mpclmul in CFLAGS and this will reduce the library
size since the generic implementation and its 8 KiB lookup table
will be omitted.

On 32-bit x86 this isn't used by default for now because by default
on 32-bit x86 the separate assembly file crc64_x86.S is used.
If --disable-assembler is used then this new CLMUL code is used
the same way as on 64-bit x86. However, a CLMUL-only build
(-msse4.1 -mpclmul) won't omit the 8 KiB lookup table on
32-bit x86 due to a currently-missing check for disabled
assembler usage.

The configure.ac check should be such that the code won't be
built if something in the toolchain doesn't support it but
--disable-clmul-crc option can be used to unconditionally
disable this feature.

CLMUL speeds up decompression of files that have compressed very
well (assuming CRC64 is used as a check type). It is know that
the CLMUL code is significantly slower than the generic code for
tiny inputs (especially 1-8 bytes but up to 16 bytes). If that
is a real-world problem then there is already a commented-out
variant that uses the generic version for small inputs.

Thanks to Ilya Kurdyukov for the original patch which was
derived from a white paper from Intel [1] (published in 2009)
and public domain code from [2] (released in 2016).

[1] https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf
[2] https://github.com/rawrunprotected/crc
2022-11-14 23:05:46 +02:00
Lasse Collin
eb0f1450ad liblzma: Use __attribute__((__constructor__)) if available.
This uses it for CRC table initializations when using --disable-small.
It avoids mythread_once() overhead. It also means that then
--disable-small --disable-threads is thread-safe if this attribute
is supported.
2022-11-14 16:00:52 +02:00
Lasse Collin
df8ad4af65 Docs: Update INSTALL and also add new prohibited options to PACKAGERS. 2022-11-09 14:41:56 +02:00
Lasse Collin
9bd317ef03 Update INSTALL for Windows and DOS and add preliminary info for z/OS. 2020-03-15 15:27:22 +02:00
Lasse Collin
43ce4ea7c7 Scripts: Put /usr/xpg4/bin to the beginning of PATH on Solaris.
This adds a configure option --enable-path-for-scripts=PREFIX
which defaults to empty except on Solaris it is /usr/xpg4/bin
to make POSIX grep and others available. The Solaris case had
been documented in INSTALL with a manual fix but it's better
to do this automatically since it is needed on most Solaris
systems anyway.

Thanks to Daniel Richard G.
2019-09-24 23:02:40 +03:00
Lasse Collin
0297863fdb Document --enable-sandbox configure option in INSTALL. 2016-12-26 20:55:52 +02:00
Lasse Collin
ac398c3baf liblzma: Disable external SHA-256 by default.
This is the sane thing to do. The conflict with OpenSSL
on some OSes and especially that the OS-provided versions
can be significantly slower makes it clear that it was
a mistake to have the external SHA-256 support enabled by
default.

Those who want it can now pass --enable-external-sha256 to
configure. INSTALL was updated with notes about OSes where
this can be a bad idea.

The SHA-256 detection code in configure.ac had some bugs that
could lead to a build failure in some situations. These were
fixed, although it doesn't matter that much now that the
external SHA-256 is disabled by default.

MINIX >= 3.2.0 uses NetBSD's libc and thus has SHA256_Init
in libc instead of libutil. Support for the libutil version
was removed.
2016-03-13 20:21:49 +02:00
Lasse Collin
3a5d755d05 Windows: Update the docs. 2015-06-19 20:21:30 +03:00
Lasse Collin
aae6a6aeda Update Solaris notes in INSTALL.
Mention the possible "make check" failure on Solaris in the
Solaris-specific section of INSTALL. It was already in
section 4.5 but it is better mention it in the OS-specific
section too.
2014-12-30 11:17:16 +02:00
Lasse Collin
7815112153 Build: POSIX shell isn't required if scripts are disabled. 2014-12-26 12:00:05 +02:00
Lasse Collin
29b95d5d66 Update INSTALL about the dependencies of the scripts. 2014-12-20 20:43:14 +02:00
Lasse Collin
3af91040bb Windows: Update build instructions. 2014-12-20 20:42:33 +02:00
Lasse Collin
e4fc1d2f95 Update INSTALL about a "make check" failure in test_scripts.sh. 2014-11-28 20:07:18 +02:00
Lasse Collin
56056571df Build: Add --disable-doc to configure. 2014-04-25 17:44:26 +03:00
Lasse Collin
6de61d8721 Update INSTALL.
Add a note about failing "make check". The source of
the problem should be fixed in libtool (if it really is
a libtool bug and not mine) but I'm unable to spend time
on that for now. Thanks to Nelson H. F. Beebe for reporting
the issue.

Add a note about a possible need to run "ldconfig" after
"make install".
2014-04-24 18:06:24 +03:00
Lasse Collin
6b44b4a775 Add native threading support on Windows.
Now liblzma only uses "mythread" functions and types
which are defined in mythread.h matching the desired
threading method.

Before Windows Vista, there is no direct equivalent to
pthread condition variables. Since this package doesn't
use pthread_cond_broadcast(), pre-Vista threading can
still be kept quite simple. The pre-Vista code doesn't
use anything that wasn't already available in Windows 95,
so the binaries should run even on Windows 95 if someone
happens to care.
2013-09-17 11:52:28 +03:00
Lasse Collin
4a238dd9b2 Document --enable-symbol-versions in INSTALL. 2012-07-04 17:05:46 +03:00
Lasse Collin
8c5b13ad59 Docs: Update MINIX 3 information in INSTALL. 2012-04-19 13:58:55 +03:00
Lasse Collin
2dcea03712 Fix compiling with IBM XL C on AIX. 2012-02-22 12:00:16 +02:00
Lasse Collin
830ba58777 Update INSTALL with a note about linker problem on OpenSolaris x86. 2011-05-17 12:21:33 +03:00
Lasse Collin
85cdf7dd4e Update INSTALL with another note about IRIX. 2011-03-31 15:06:58 +03:00
Lasse Collin
ce34ec4f54 Update docs. 2010-10-19 10:21:08 +03:00
Lasse Collin
8dad2fd693 Updated INSTALL. 2010-09-10 14:30:07 +03:00
Lasse Collin
507a4a4dea Windows: build.sh is a bash script so name it correctly. 2010-07-27 20:45:03 +03:00
Lasse Collin
0d3489efca Updated INSTALL. 2010-05-10 19:57:24 +03:00
Lasse Collin
9886d436ff Change the default of --enable-assume-ram from 32 to 128 MiB.
This is to allow files created with "xz -9" to be decompressed
if the amount of RAM cannot be determined.
2010-03-07 13:34:34 +02:00
Lasse Collin
2901a8e7e8 Updated INSTALL. 2010-01-31 23:31:14 +02:00
Lasse Collin
29fd321033 Add support for --enable-assume-ram=SIZE. 2009-10-02 14:35:56 +03:00
Lasse Collin
5e000ff00d Added OpenVMS-specific information to INSTALL. 2009-09-22 18:59:56 +03:00
Lasse Collin
173368911c Mention in INSTALL that --enable-small doesn't modify CFLAGS. 2009-09-02 09:43:51 +03:00
Lasse Collin
2331f5f97a Add more OS/2 specific info to INSTALL. 2009-08-30 17:28:52 +03:00
Lasse Collin
66da129c8e Updated INSTALL and PACKAGERS to match the changes
made in --enable-dynamic.
2009-08-13 15:15:37 +03:00
Lasse Collin
99f9e879a6 Major documentation update.
Installation and packaging instructions were added.
README and other generic docs were revised.

Some of the documentation files are now installed to $docdir.
2009-07-19 13:14:20 +03:00