Commit Graph

10 Commits

Author SHA1 Message Date
Lasse Collin 22af94128b Add SPDX license identifier into 0BSD source code files. 2024-02-14 18:31:16 +02:00
Lasse Collin 689e0228ba Change most public domain parts to 0BSD.
Translations and doc/xz-file-format.txt and doc/lzma-file-format.txt
were not touched.

COPYING.0BSD was added.
2024-02-14 18:31:12 +02:00
Jia Tan 761f5b69a4 liblzma: Rename crc32_aarch64.h to crc32_arm64.h.
Even though the proper name for the architecture is aarch64, this
project uses ARM64 throughout. So the rename is for consistency.

Additionally, crc32_arm64.h was slightly refactored for the following
changes:

   * Added MSVC, FreeBSD, and macOS support in
     is_arch_extension_supported().

   * crc32_arch_optimized() now checks the size when aligning the
     buffer.

   * crc32_arch_optimized() loop conditions were slightly modified to
     avoid both decrementing the size and incrementing the buffer
     pointer.

   * Use the intrinsic wrappers defined in <arm_acle.h> because GCC and
     Clang name them differently.

   * Minor spacing and comment changes.
2024-02-01 20:09:11 +08:00
Chenxi Mao 849d0f282a Speed up CRC32 calculation on ARM64
The CRC32 instructions in ARM64 can calculate the CRC32 result
for 8 bytes in a single operation, making the use of ARM64
instructions much faster compared to the general CRC32 algorithm.

Optimized CRC32 will be enabled if ARM64 has CRC extension
running on Linux.

Signed-off-by: Chenxi Mao <chenxi.mao2013@gmail.com>
2024-01-27 21:49:26 +08:00
Lasse Collin 419f55f9df liblzma: Avoid extern lzma_crc32_clmul() and lzma_crc64_clmul().
A CLMUL-only build will have the crcxx_clmul() inlined into
lzma_crcxx(). Previously a jump to the extern lzma_crcxx_clmul()
was needed. Notes about shared liblzma on ELF platforms:

  - On platforms that support ifunc and -fvisibility=hidden, this
    was silly because CLMUL-only build would have that single extra
    jump instruction of extra overhead.

  - On platforms that support neither -fvisibility=hidden nor linker
    version script (liblzma*.map), jumping to lzma_crcxx_clmul()
    would go via PLT so a few more instructions of overhead (still
    not a big issue but silly nevertheless).

There was a downside with static liblzma too: if an application only
needs lzma_crc64(), static linking would make the linker include the
CLMUL code for both CRC32 and CRC64 from crc_x86_clmul.o even though
the CRC32 code wouldn't be needed, thus increasing code size of the
executable (assuming that -ffunction-sections isn't used).

Also, now compilers are likely to inline crc_simd_body()
even if they don't support the always_inline attribute
(or MSVC's __forceinline). Quite possibly all compilers
that build the code do support such an attribute. But now
it likely isn't a problem even if the attribute wasn't supported.

Now all x86-specific stuff is in crc_x86_clmul.h. If other archs
The other archs can then have their own headers with their own
is_clmul_supported() and crcxx_clmul().

Another bonus is that the build system doesn't need to care if
crc_clmul.c is needed.

is_clmul_supported() stays as inline function as it's not needed
when doing a CLMUL-only build (avoids a warning about unused function).
2024-01-11 14:29:42 +02:00
Jia Tan 105c7ca90d Build: Remove check for COND_CHECK_CRC32 in check/Makefile.inc.
Currently crc32 is always enabled, so COND_CHECK_CRC32 must always be
set. Because of this, it makes the recent change to conditionally
compile check/crc_clmul.c appear wrong since that file has CLMUL
implementations for both CRC32 and CRC64.
2023-10-19 16:23:32 +08:00
Jia Tan 8c0f9376f5 liblzma: Create crc_clmul.c.
Both crc32_clmul() and crc64_clmul() are now exported from
crc32_clmul.c as lzma_crc32_clmul() and lzma_crc64_clmul(). This
ensures that is_clmul_supported() (now lzma_is_clmul_supported()) is
not duplicated between crc32_fast.c and crc64_fast.c.

Also, it encapsulates the complexity of the CLMUL implementations into a
single file and reduces the complexity of crc32_fast.c and crc64_fast.c.
Before, CLMUL code was present in crc32_fast.c, crc64_fast.c, and
crc_common.h.

During the conversion, various cleanups were applied to code (thanks to
Lasse Collin) including:

- Require using semicolons with MASK_/L/H/LH macros.
- Variable typing and const handling improvements.
- Improvements to comments.
- Fixes to the pragmas used.
- Removed unneeded variables.
- Whitespace improvements.
- Fixed CRC_USE_GENERIC_FOR_SMALL_INPUTS handling.
- Silenced warnings and removed the need for some #pragmas
2023-10-18 23:54:36 +08:00
Hans Jansen 233885a437 liblzma: Rename crc_macros.h to crc_common.h. 2023-10-13 20:54:05 +08:00
Lasse Collin b94aa0c838 liblzma: Try to use SHA-256 from the operating system.
If the operating system libc or other base libraries
provide SHA-256, use that instead of our own copy.
Note that this doesn't use OpenSSL or libgcrypt or
such libraries to avoid creating dependencies to
other packages.

This supports at least FreeBSD, NetBSD, OpenBSD, Solaris,
MINIX, and Darwin. They all provide similar but not
identical SHA-256 APIs; everyone is a little different.

Thanks to Wim Lewis for the original patch, improvements,
and testing.
2011-05-21 15:08:44 +03:00
Lasse Collin f42ee98166 Build system fixes
Don't use libtool convenience libraries to avoid recently
discovered long-standing subtle but somewhat severe bugs
in libtool (at least 1.5.22 and 2.2.6 are affected). It
was found when porting XZ Utils to Windows
<http://lists.gnu.org/archive/html/libtool/2009-06/msg00070.html>
but the problem is significant also e.g. on GNU/Linux.

Unless --disable-shared is passed to configure, static
library built from a set of convenience libraries will
contain PIC objects. That is, while libtool builds non-PIC
objects too, only PIC objects will be used from the
convenience libraries. On 32-bit x86 (tested on mobile XP2400+),
using PIC instead of non-PIC makes the decompressor 10 % slower
with the default CFLAGS.

So while xz was linked against static liblzma by default,
it got the slower PIC objects unless --disable-shared was
used. I tend develop and benchmark with --disable-shared
due to faster build time, so I hadn't noticed the problem
in benchmarks earlier.

This commit also adds support for building Windows resources
into liblzma and executables.
2009-06-30 17:09:57 +03:00