devs/foxbox
1
0
Fork 0
forked from len0rd/rockbox
Code Pull requests Activity

Smaller & faster (on our targets) fixed point exp() with a multiplication.

Browse source 
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@10454 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Jens Arnold 2006-08-04 07:02:34 +00:00
parent 737e4768a1
commit f212e6cf5f
1 changed files with 1 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

10
apps/plugins/lib/gray_core.c
View file

@ -226,15 +226,7 @@ static int exp_s16p16(int x)
t = x - 0x007e1; if (t >= 0) x = t, y += y >> 5;
t = x - 0x003f8; if (t >= 0) x = t, y += y >> 6;
t = x - 0x001fe; if (t >= 0) x = t, y += y >> 7;
if (x & 0x100) y += y >> 8;
if (x & 0x080) y += y >> 9;
if (x & 0x040) y += y >> 10;
if (x & 0x020) y += y >> 11;
if (x & 0x010) y += y >> 12;
if (x & 0x008) y += y >> 13;
if (x & 0x004) y += y >> 14;
if (x & 0x002) y += y >> 15;
if (x & 0x001) y += y >> 16;
y += ((y >> 8) * x) >> 8;
return y;
}