5988765741
The find_first_set and find_last_set method is not optimal for neon, it
needs to be improved by synthesized with horizontal adds(vaddv) which
will reduce the generated assembly code. In the following cases,
vaddvq_s16 will generate 2 instructions but vpadd_s16 will generate 4
instructions:
# vaddvq_s16
vaddvq_s16(__asint);
// addv h0, v1.8h
// smov w1, v0.h[0]
# vpadd_s16
vpaddq_s16(vpaddq_s16(vpaddq_s16(__asint, __zero), __zero), __zero)[0]
// addp v1.8h,v1.8h,v2.8h
// addp v1.8h,v1.8h,v2.8h
// addp v1.8h,v1.8h,v2.8h
// smov w1, v1.h[0]
#
libstdc++-v3/ChangeLog:
* include/experimental/bits/simd_neon.h: Replace repeated vpadd
calls with a single vaddv for aarch64.
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| .. | ||
| config | ||
| doc | ||
| include | ||
| libsupc++ | ||
| po | ||
| python | ||
| scripts | ||
| src | ||
| testsuite | ||
| acinclude.m4 | ||
| aclocal.m4 | ||
| ChangeLog | ||
| ChangeLog-1998 | ||
| ChangeLog-1999 | ||
| ChangeLog-2000 | ||
| ChangeLog-2001 | ||
| ChangeLog-2002 | ||
| ChangeLog-2003 | ||
| ChangeLog-2004 | ||
| ChangeLog-2005 | ||
| ChangeLog-2006 | ||
| ChangeLog-2007 | ||
| ChangeLog-2008 | ||
| ChangeLog-2009 | ||
| ChangeLog-2010 | ||
| ChangeLog-2011 | ||
| ChangeLog-2012 | ||
| ChangeLog-2013 | ||
| ChangeLog-2014 | ||
| ChangeLog-2015 | ||
| ChangeLog-2016 | ||
| ChangeLog-2017 | ||
| ChangeLog-2018 | ||
| ChangeLog-2019 | ||
| ChangeLog-2020 | ||
| config.h.in | ||
| configure | ||
| configure.ac | ||
| configure.host | ||
| crossconfig.m4 | ||
| fragment.am | ||
| linkage.m4 | ||
| Makefile.am | ||
| Makefile.in | ||
| README | ||
file: libstdc++-v3/README New users may wish to point their web browsers to the file index.html in the 'doc/html' subdirectory. It contains brief building instructions and notes on how to configure the library in interesting ways.