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Convert a number of places in core and plugins to use the BIT_N() macro instead of 1<<n. Speeds up things on SH1, and also reduces core binsize. Most notable speedups: 1 bit lcd driver: drawpixel +20%, drawline + 27%, hline +5%; jpeg viewer: +8% for 1/8 scaling. Other targets are unaffected.

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21205 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Jens Arnold 2009-06-07 21:27:05 +00:00
parent c3182ec333
commit 1d6df54df2
24 changed files with 88 additions and 70 deletions
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3
apps/plugins/lib/fixedpoint.c
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@ -22,6 +22,7 @@
****************************************************************************/
#include <inttypes.h>
#include "plugin.h"
#include "fixedpoint.h"
/* Inverse gain of circular cordic rotation in s0.31 format. */
@ -144,7 +145,7 @@ long fsincos(unsigned long phase, long *cos)
*/
long fsqrt(long a, unsigned int fracbits)
{
long b = a/2 + (1 << fracbits); /* initial approximation */
long b = a/2 + BIT_N(fracbits); /* initial approximation */
unsigned n;
const unsigned iterations = 4;