rockbox/apps/codecs/demac/libdemac/predictor-arm.S, branch master

Add codecs to librbcodec.

2012-04-25T20:13:20+00:00

Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97
Reviewed-on: http://gerrit.rockbox.org/137
Reviewed-by: Nils Wallménius 
Tested-by: Nils Wallménius

FS#11335 by me: make ARM assembly functions thumb-friendly

2010-06-11T04:41:36+00:00

We can't pop into pc on ARMv4t when using thumb: the T bit won't be
modified if we are returning to a thumb function
Code running on ARMv4t should use the new ldrpc / ldmpc macros instead
of ldr pc, [sp], #4 and ldm(cond) sp!, {regs, pc}
No modification on pure ARM builds and ARMv5+

Note: USE_THUMB is currently never defined, no targets can currently be
built with -mthumb, see FS#6734

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@26756 a1c6a512-1295-4272-9138-f99709370657

Remove all tabs within codec path.

2010-02-22T19:44:05+00:00

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@24862 a1c6a512-1295-4272-9138-f99709370657

Don't use ldrd/strd on ARMv5 since not all revisions support them and the gain from using them is minimal (basically code size only).

2009-07-17T09:17:54+00:00

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21916 a1c6a512-1295-4272-9138-f99709370657

Assembler optimised mono predictor for ARM. Speedup for -c1000 mono is ~5% on PP, ~8% on Gigabeat S (less for higher compression levels). Also fix some overlooked comments in the stereo predictor.

2008-12-09T23:20:59+00:00

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19375 a1c6a512-1295-4272-9138-f99709370657

On ARM9TDMI (e.g. Gigabeat F) it's faster to use a ldr/str pair than add+ldmia/stmia for 2 registers. On ARM7TDMI a str pair is equally fast, so go for the simpler macro and use it for all ARMv4.

2008-11-27T22:07:46+00:00

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19250 a1c6a512-1295-4272-9138-f99709370657

Speed up the predictor a little by using ldrd/strd on ARMv5+. This required shuffling around the register allocation somewhat. Performance on ARMv4 is unaffected.

2008-11-27T20:52:23+00:00

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19248 a1c6a512-1295-4272-9138-f99709370657

Reorder instructions to avoid pipeline stalls on ARMv6 wherever possible (sometimes using different registers to allow this). Speeds up the predictor by almost 20% on ARMv6 (overall speedup for -c1000 is 5%), and might also help a bit on ARMv5. ARMv4 speed is unaffected.

2008-11-24T23:09:09+00:00

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19210 a1c6a512-1295-4272-9138-f99709370657

Branch optimisation in both C (giving hints to gcc - verified using -fprofile-arcs and gcov) and asm files. Biggest effect on coldfire (-c1000: +8%, -c2000: +5%), but ARM also profits a bit (less than 1% on ARM7TDMI, around 1% on ARM1136).

2008-11-24T18:40:49+00:00

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19199 a1c6a512-1295-4272-9138-f99709370657

Centralise compile-time configuration.

2008-11-16T17:49:37+00:00

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19121 a1c6a512-1295-4272-9138-f99709370657