Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: intvnut at gmail dot com
Target Milestone: ---
GCC 4.1.2 previously warned about p being used uninitialized in code such as
the following:
#include
void
--- Comment #6 from intvnut at gmail dot com 2008-04-29 03:42 ---
(In reply to comment #5)
It should be possible to have an alternate implementation in libgcc2.c by
means
of just selecting on a proper architecture define or the size of the argument
mode.
I see where it would go
--- Comment #4 from intvnut at gmail dot com 2008-04-25 12:29 ---
Is there a mechanism to provide different implementations based on the target
(or in this case, class of target)? The byte count approach certainly is more
appropriate for 8-bit targets, sure, but what about the rest
dot org
ReportedBy: intvnut at gmail dot com
GCC build triplet: x86_64-unknown-linux-gnu
GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36041
--- Comment #1 from intvnut at gmail dot com 2008-04-25 00:36 ---
Created an attachment (id=15529)
-- (http://gcc.gnu.org/bugzilla/attachment.cgi?id=15529action=view)
Popcount sample implementations
These implementations are derived from insights in Henry S. Warren's Hacker's
Delight
--- Comment #2 from intvnut at gmail dot com 2008-04-25 00:39 ---
When run on my Opteron 280 system, the four separate implementations give the
following run times:
popcount64_1 = 1313 clocks
popcount64_2 = 648 clocks
popcount64_3 = 374 clocks
popcount64_4 = 549 clocks
