------- Comment #3 from dje at gcc dot gnu dot org 2005-10-28 17:30 -------
The misprediction causes (or at least contributes to) compute_alignments in
final.c not aligning the critical loop in longest_match. The recent changes to
bb-reorder.c moved the start of the loop from an ideal alignment to the worst
alignment, causing a 8-10% performance drop due to instruction fetch problems.
Without the explicit alignment directives omitted because of misprediction, the
alignment of the loop is random.
--
dje at gcc dot gnu dot org changed:
What |Removed |Added
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CC| |dberlin at gcc dot gnu dot
| |org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24487
