The uses of these functions do not justify the level of
micro-optimization we've done and may even hurt performance in some
cases (e.g., due to using function pointers). This commit removes
all architecture-specific implementations of pg_popcount{32,64} and
converts the portable ones to inlined functions in pg_bitutils.h.
These inlined versions should produce the same code as before (but
inlined), so in theory this is a net gain for many machines. A
follow-up commit will replace the remaining loops over these
word-length popcount functions with calls to pg_popcount(), further
reducing the need for architecture-specific implementations.
Suggested-by: John Naylor <johncnaylorls@gmail.com>
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Reviewed-by: Greg Burd <greg@burd.me>
Discussion: https://postgr.es/m/CANWCAZY7R%2Biy%2Br9YM_sySNydHzNqUirx1xk0tB3ej5HO62GdgQ%40mail.gmail.com
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.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.