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| author | Jens Arnold <amiconn@rockbox.org> | 2006-08-04 07:02:34 +0000 |
|---|---|---|
| committer | Jens Arnold <amiconn@rockbox.org> | 2006-08-04 07:02:34 +0000 |
| commit | f212e6cf5fb6327b51abdf1af2b102f87c896a32 (patch) | |
| tree | 991e6e6704a53c9b51177f4e2205aa28d7931a35 /apps/plugins/lib | |
| parent | 737e4768a1783c03b2dc2fb29eba43d4b76350bb (diff) | |
| download | rockbox-f212e6cf5fb6327b51abdf1af2b102f87c896a32.zip rockbox-f212e6cf5fb6327b51abdf1af2b102f87c896a32.tar.gz rockbox-f212e6cf5fb6327b51abdf1af2b102f87c896a32.tar.bz2 rockbox-f212e6cf5fb6327b51abdf1af2b102f87c896a32.tar.xz | |
Smaller & faster (on our targets) fixed point exp() with a multiplication.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@10454 a1c6a512-1295-4272-9138-f99709370657
Diffstat (limited to 'apps/plugins/lib')
| -rw-r--r-- | apps/plugins/lib/gray_core.c | 10 |
1 files changed, 1 insertions, 9 deletions
diff --git a/apps/plugins/lib/gray_core.c b/apps/plugins/lib/gray_core.c index 2b4d2c5..5f56521 100644 --- a/apps/plugins/lib/gray_core.c +++ b/apps/plugins/lib/gray_core.c @@ -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; } |