- Status Closed
- Percent Complete
- Task Type Patches
- Category
-
Assigned To
Jörg Hohensohn - Operating System
- Severity Low
- Priority Very Low
- Reported Version
- Due in Version Undecided
-
Due Date
Undecided
- Votes
- Private
Attached to Project: Rockbox
Opened by Magnus Holmgren - 2003-08-09
Last edited by Jörg Hohensohn - 2003-10-12
Opened by Magnus Holmgren - 2003-08-09
Last edited by Jörg Hohensohn - 2003-10-12
FS#1604 - Faster rolo_load
This patch speeds up the rolo_load function, by
implementing the descrambling part in assembler (and in
a more efficient form). Also, the descrambling
calculates the checksum as it goes, saving a little
more time. Descrambling time is reduced from about 1.6
to 0.3 seconds (on a player, with a .mod file on
122,534 bytes).
As the patch also moves the "critical" part of
rolo_load to the internal RAM (this, including
descrambling and checksumming, needs 88 bytes), the
.topcode section is removed.
descramble.S is attached separately, because I don't
know how to make cvs diff include it in the patch… :/
Adding descramble.S as well.
Did some more tweaking on descramble.S, so that it is ~30%
faster. :)