The following patch attempts to use x86 SHA ISA if available to speed
up in my testing about 2.5x sha1 build-id processing (in my case on
AMD Ryzen 5 3600) while producing the same result.
I believe AArch64 has similar HW acceleration for SHA1, perhaps it
could be added similarly.
Note, seems lld uses BLAKE3 rather than md5/sha1. I think it would be
a bad idea to lie to users, if they choose --buildid=sha1, we should
be using SHA1, not some other checksum, but perhaps we could add some other
--buildid= styles and perhaps make one of the new the default.
Tested on x86_64-linux, both on Intel i9-7960X (which doesn't have
sha_ni ISA support) without/with the patch and on AMD Ryzen 5 3600
(which does have it) without/with the patch.
2023-11-28 Jakub Jelinek <jakub@redhat.com>
include/
* sha1.h (sha1_process_bytes_fn): New typedef.
(sha1_choose_process_bytes): Declare.
libiberty/
* configure.ac (HAVE_X86_SHA1_HW_SUPPORT): New check.
* sha1.c: If HAVE_X86_SHA1_HW_SUPPORT is defined, include x86intrin.h
and cpuid.h.
(sha1_hw_process_bytes, sha1_hw_process_block,
sha1_choose_process_bytes): New functions.
* config.in: Regenerated.
* configure: Regenerated.
ld/
* ldbuildid.c (generate_build_id): Use sha1_choose_process_bytes ()
instead of &sha1_process_bytes.
This directory contains the -liberty library of free software.
It is a collection of subroutines used by various GNU programs.
Current members include:
getopt -- get options from command line
obstack -- stacks of arbitrarily-sized objects
strerror -- error message strings corresponding to errno
strtol -- string-to-long conversion
strtoul -- string-to-unsigned-long conversion
We expect many of the GNU subroutines that are floating around to
eventually arrive here.
The library must be configured from the top source directory. Don't
try to run configure in this directory. Follow the configuration
instructions in ../README.
Please report bugs to https://gcc.gnu.org/bugzilla/ and send fixes to
"gcc-patches@gcc.gnu.org". Thank you.
ADDING A NEW FILE
=================
There are two sets of files: Those that are "required" will be
included in the library for all configurations, while those
that are "optional" will be included in the library only if "needed."
To add a new required file, edit Makefile.in to add the source file
name to CFILES and the object file to REQUIRED_OFILES.
To add a new optional file, it must provide a single function, and the
name of the function must be the same as the name of the file.
* Add the source file name to CFILES in Makefile.in and the object
file to CONFIGURED_OFILES.
* Add the function to name to the funcs shell variable in
configure.ac.
* Add the function to the AC_CHECK_FUNCS lists just after the
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are never executed; they are there to make autoheader work
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* Consider the special cases of building libiberty; as of this
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object file to LIBOBJS, and add the function name to the case
controlling whether to define HAVE_func.
Finally, in the build directory of libiberty, configure with
"--enable-maintainer-mode", run "make maint-deps" to update
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functions.texi.
The optional file you've added (e.g. getcwd.c) should compile and work
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compile on hosts where it is not needed.
ADDING A NEW CONFIGURATION
==========================
On most hosts you should be able to use the scheme for automatically
figuring out which files are needed. In that case, you probably
don't need a special Makefile stub for that configuration.
If the fully automatic scheme doesn't work, you may be able to get
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regardless of whatever might be in the C library.