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Tom Lane 764a554d6f Avoid a performance regression in float overflow/underflow detection. Commit `6bf0bc842` replaced float.c's CHECKFLOATVAL() macro with static inline subroutines, but that wasn't too well thought out. In the original coding, the unlikely condition (isinf(result) or result == 0) was checked first, and the inf_is_valid or zero_is_valid condition only afterwards. The inline-subroutine coding caused that to be swapped around, which is pretty horrid for performance because (a) in common cases the is_valid condition is twice as expensive to evaluate (e.g., requiring two isinf() calls not one) and (b) in common cases the is_valid condition is false, requiring us to perform the unlikely-condition check anyway. Net result is that one isinf() call becomes two or three, resulting in visible performance loss as reported by Keisuke Kuroda. The original fix proposal was to revert the replacement of the macro, but on second thought, that macro was just a bad idea from the beginning: if anything it's a net negative for readability of the code. So instead, let's just open-code all the overflow/underflow tests, being careful to test the unlikely condition first (and mark it unlikely() to help the compiler get the point). Also, rather than having N copies of the actual ereport() calls, collapse those into out-of-line error subroutines to save some code space. This does mean that the error file/line numbers won't be very helpful for figuring out where the issue really is --- but we'd already burned that bridge by putting the ereports into static inlines. In HEAD, check_float[48]_val() are gone altogether. In v12, leave them present in float.h but unused in the core code, just in case some extension is depending on them. Emre Hasegeli, with some kibitzing from me and Andres Freund Discussion: https://postgr.es/m/CANDwggLe1Gc1OrRqvPfGE=kM9K0FSfia0hbeFCEmwabhLz95AA@mail.gmail.com		2020-02-13 13:37:43 -05:00
config	Update config.guess and config.sub	2019-04-27 14:25:00 +02:00
contrib	In jsonb_plpython.c, suppress warning message from gcc 10.	2020-01-30 18:26:13 -05:00
doc	Doc: fix old oversights in GRANT/REVOKE documentation.	2020-02-12 14:13:13 -05:00
src	Avoid a performance regression in float overflow/underflow detection.	2020-02-13 13:37:43 -05:00
.dir-locals.el	Make Emacs perl-mode indent more like perltidy.	2019-01-13 11:32:31 -08:00
.gitattributes	Add XSL stylesheet to fix up SVG files	2019-06-19 21:26:42 +02:00
.gitignore	Support for optimizing and emitting code in LLVM JIT provider.	2018-03-22 11:05:22 -07:00
aclocal.m4	Fix configure's AC_CHECK_DECLS tests to work correctly with clang.	2018-11-19 12:01:47 -05:00
configure	Stamp 12.2.	2020-02-10 17:14:51 -05:00
configure.in	Stamp 12.2.	2020-02-10 17:14:51 -05:00
COPYRIGHT	Update copyrights for 2020	2020-01-01 12:21:45 -05:00
GNUmakefile.in	Integrate cpluspluscheck into build system.	2019-05-31 12:36:17 -07:00
HISTORY	Change documentation references to PG website to use https: not http:	2017-05-20 21:50:47 -04:00
Makefile	Don't unset MAKEFLAGS in non-GNU Makefile.	2019-06-25 09:36:21 +12:00
README	Change documentation references to PG website to use https: not http:	2017-05-20 21:50:47 -04:00
README.git	Change documentation references to PG website to use https: not http:	2017-05-20 21:50:47 -04:00

README

PostgreSQL Database Management System
=====================================

This directory contains the source code distribution of the PostgreSQL
database management system.

PostgreSQL is an advanced object-relational database management system
that supports an extended subset of the SQL standard, including
transactions, foreign keys, subqueries, triggers, user-defined types
and functions.  This distribution also contains C language bindings.

PostgreSQL has many language interfaces, many of which are listed here:

	https://www.postgresql.org/download

See the file INSTALL for instructions on how to build and install
PostgreSQL.  That file also lists supported operating systems and
hardware platforms and contains information regarding any other
software packages that are required to build or run the PostgreSQL
system.  Copyright and license information can be found in the
file COPYRIGHT.  A comprehensive documentation set is included in this
distribution; it can be read as described in the installation
instructions.

The latest version of this software may be obtained at
https://www.postgresql.org/download/.  For more information look at our
web site located at https://www.postgresql.org/.