postgresql/contrib/ltree
Tom Lane 02a6a54ecd Make use of compiler builtins and/or assembly for CLZ, CTZ, POPCNT.
Test for the compiler builtins __builtin_clz, __builtin_ctz, and
__builtin_popcount, and make use of these in preference to
handwritten C code if they're available.  Create src/port
infrastructure for "leftmost one", "rightmost one", and "popcount"
so as to centralize these decisions.

On x86_64, __builtin_popcount generally won't make use of the POPCNT
opcode because that's not universally supported yet.  Provide code
that checks CPUID and then calls POPCNT via asm() if available.
This requires indirecting through a function pointer, which is
an annoying amount of overhead for a one-instruction operation,
but it's probably not worth working harder than this for our
current use-cases.

I'm not sure we've found all the existing places that could profit
from this new infrastructure; but we at least touched all the
ones that used copied-and-pasted versions of the bitmapset.c code,
and got rid of multiple copies of the associated constant arrays.

While at it, replace c-compiler.m4's one-per-builtin-function
macros with a single one that can handle all the cases we need
to worry about so far.  Also, because I'm paranoid, make those
checks into AC_LINK checks rather than just AC_COMPILE; the
former coding failed to verify that libgcc has support for the
builtin, in cases where it's not inline code.

David Rowley, Thomas Munro, Alvaro Herrera, Tom Lane

Discussion: https://postgr.es/m/CAKJS1f9WTAGG1tPeJnD18hiQW5gAk59fQ6WK-vfdAKEHyRg2RA@mail.gmail.com
2019-02-15 23:22:33 -05:00
..
data Add ltree data type to contrib, from Teodor Sigaev and Oleg Bartunov. 2002-07-30 16:40:34 +00:00
expected Fix crash in contrib/ltree's lca() function for empty input array. 2018-07-13 18:45:30 -04:00
sql Fix crash in contrib/ltree's lca() function for empty input array. 2018-07-13 18:45:30 -04:00
_ltree_gist.c Make use of compiler builtins and/or assembly for CLZ, CTZ, POPCNT. 2019-02-15 23:22:33 -05:00
_ltree_op.c Make DatumGetFoo/PG_GETARG_FOO/PG_RETURN_FOO macro names more consistent. 2017-09-18 15:21:23 -04:00
.gitignore Support "make check" in contrib 2011-04-25 22:27:11 +03:00
crc32.c Remove useless duplicate inclusions of system header files. 2017-02-25 16:12:55 -05:00
crc32.h Remove cvs keywords from all files. 2010-09-20 22:08:53 +02:00
lquery_op.c Make DatumGetFoo/PG_GETARG_FOO/PG_RETURN_FOO macro names more consistent. 2017-09-18 15:21:23 -04:00
ltree_gist.c Change TRUE/FALSE to true/false 2017-11-08 11:37:28 -05:00
ltree_io.c Make DatumGetFoo/PG_GETARG_FOO/PG_RETURN_FOO macro names more consistent. 2017-09-18 15:21:23 -04:00
ltree_op.c Allow btree comparison functions to return INT_MIN. 2018-10-05 16:01:29 -04:00
ltree--1.0--1.1.sql Update extensions with GIN/GIST support for parallel query. 2016-06-14 13:34:37 -04:00
ltree--1.1.sql Update extensions with GIN/GIST support for parallel query. 2016-06-14 13:34:37 -04:00
ltree--unpackaged--1.0.sql Fix typos in some error messages thrown by extension scripts when fed to psql. 2014-08-25 18:30:37 +02:00
ltree.control Handle contrib's GIN/GIST support function signature changes honestly. 2016-06-09 16:44:25 -04:00
ltree.h Make DatumGetFoo/PG_GETARG_FOO/PG_RETURN_FOO macro names more consistent. 2017-09-18 15:21:23 -04:00
ltreetest.sql Remove cvs keywords from all files. 2010-09-20 22:08:53 +02:00
ltxtquery_io.c Make DatumGetFoo/PG_GETARG_FOO/PG_RETURN_FOO macro names more consistent. 2017-09-18 15:21:23 -04:00
ltxtquery_op.c Make DatumGetFoo/PG_GETARG_FOO/PG_RETURN_FOO macro names more consistent. 2017-09-18 15:21:23 -04:00
Makefile Provide for contrib and pgxs modules to install include files. 2018-07-31 20:07:39 +01:00