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436e4d5b96
This variant of strlen uses vector loads and operations to reduce the size of the code and also eliminate the non-ascii fallback. This works very well for falkor because of its two vector units and efficient vector ops. In the best case it reduces latency of cases in bench-strlen by 48%, with gains throughout the benchmark. strlen-walk also sees uniform gains in the 5%-15% range. Overall the routine appears to work better than the stock one for falkor regardless of the benchmark, length of string or cache state. The same cannot be said of a53 and a72 though. a53 performance was greatly reduced and for a72 it was a bit of a mixed bag, slightly on the negative side but I reckon it might be fast in some situations. * sysdeps/aarch64/strlen.S (__strlen): Rename to STRLEN. [!STRLEN](STRLEN): Set to __strlen. * sysdeps/aarch64/multiarch/strlen.c: New file. * sysdeps/aarch64/multiarch/strlen_generic.S: Likewise. * sysdeps/aarch64/multiarch/strlen_asimd.S: Likewise. * sysdeps/aarch64/multiarch/ifunc-impl-list.c (__libc_ifunc_impl_list): Add strlen. * sysdeps/aarch64/multiarch/Makefile (sysdep_routines): Add strlen_generic and strlen_asimd. Reviewed-By: szabolcs.nagy@arm.com CC: pinskia@gmail.com |
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| benchtests | ||
| bits | ||
| catgets | ||
| ChangeLog.old | ||
| conform | ||
| crypt | ||
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| debug | ||
| dirent | ||
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| include | ||
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| locale | ||
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| mach | ||
| malloc | ||
| manual | ||
| math | ||
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| stdlib | ||
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| ChangeLog | ||
| config.h.in | ||
| config.make.in | ||
| configure | ||
| configure.ac | ||
| COPYING | ||
| COPYING.LIB | ||
| extra-lib.mk | ||
| gen-locales.mk | ||
| INSTALL | ||
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| libof-iterator.mk | ||
| LICENSES | ||
| MAINTAINERS | ||
| Makeconfig | ||
| Makefile | ||
| Makefile.in | ||
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| o-iterator.mk | ||
| README | ||
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| version.h | ||
This directory contains the sources of the GNU C Library. See the file "version.h" for what release version you have. The GNU C Library is the standard system C library for all GNU systems, and is an important part of what makes up a GNU system. It provides the system API for all programs written in C and C-compatible languages such as C++ and Objective C; the runtime facilities of other programming languages use the C library to access the underlying operating system. In GNU/Linux systems, the C library works with the Linux kernel to implement the operating system behavior seen by user applications. In GNU/Hurd systems, it works with a microkernel and Hurd servers. The GNU C Library implements much of the POSIX.1 functionality in the GNU/Hurd system, using configurations i[4567]86-*-gnu. When working with Linux kernels, this version of the GNU C Library requires Linux kernel version 3.2 or later. Also note that the shared version of the libgcc_s library must be installed for the pthread library to work correctly. The GNU C Library supports these configurations for using Linux kernels: aarch64*-*-linux-gnu alpha*-*-linux-gnu arm-*-linux-gnueabi hppa-*-linux-gnu i[4567]86-*-linux-gnu x86_64-*-linux-gnu Can build either x86_64 or x32 ia64-*-linux-gnu m68k-*-linux-gnu microblaze*-*-linux-gnu mips-*-linux-gnu mips64-*-linux-gnu powerpc-*-linux-gnu Hardware or software floating point, BE only. powerpc64*-*-linux-gnu Big-endian and little-endian. s390-*-linux-gnu s390x-*-linux-gnu riscv64-*-linux-gnu sh[34]-*-linux-gnu sparc*-*-linux-gnu sparc64*-*-linux-gnu If you are interested in doing a port, please contact the glibc maintainers; see http://www.gnu.org/software/libc/ for more information. See the file INSTALL to find out how to configure, build, and install the GNU C Library. You might also consider reading the WWW pages for the C library at http://www.gnu.org/software/libc/. The GNU C Library is (almost) completely documented by the Texinfo manual found in the `manual/' subdirectory. The manual is still being updated and contains some known errors and omissions; we regret that we do not have the resources to work on the manual as much as we would like. For corrections to the manual, please file a bug in the `manual' component, following the bug-reporting instructions below. Please be sure to check the manual in the current development sources to see if your problem has already been corrected. Please see http://www.gnu.org/software/libc/bugs.html for bug reporting information. We are now using the Bugzilla system to track all bug reports. This web page gives detailed information on how to report bugs properly. The GNU C Library is free software. See the file COPYING.LIB for copying conditions, and LICENSES for notices about a few contributions that require these additional notices to be distributed. License copyright years may be listed using range notation, e.g., 1996-2015, indicating that every year in the range, inclusive, is a copyrightable year that would otherwise be listed individually.