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authorJens Arnold <amiconn@rockbox.org>2009-08-16 12:41:04 +0000
committerJens Arnold <amiconn@rockbox.org>2009-08-16 12:41:04 +0000
commit3d6f86eb2ff21f12d9f884a8271aa783f5046ae0 (patch)
tree445686f4dbced712a4c9687e525b54145491d2ed /apps/codecs/libatrac/fixp_math.c
parent90ea3e97163fc2c34c7d114af8e36e48f4c680f2 (diff)
downloadrockbox-3d6f86eb2ff21f12d9f884a8271aa783f5046ae0.tar.gz
rockbox-3d6f86eb2ff21f12d9f884a8271aa783f5046ae0.zip
Make those functions actually inline. Around 20% speedup on coldfire, 10% speedup on arm.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@22344 a1c6a512-1295-4272-9138-f99709370657
Diffstat (limited to 'apps/codecs/libatrac/fixp_math.c')
-rw-r--r--apps/codecs/libatrac/fixp_math.c66
1 files changed, 0 insertions, 66 deletions
diff --git a/apps/codecs/libatrac/fixp_math.c b/apps/codecs/libatrac/fixp_math.c
deleted file mode 100644
index 3f578a1ade..0000000000
--- a/apps/codecs/libatrac/fixp_math.c
+++ /dev/null
@@ -1,66 +0,0 @@
1#include "fixp_math.h"
2
3inline int32_t fixmul31(int32_t x, int32_t y)
4{
5 int64_t temp;
6 temp = x;
7 temp *= y;
8
9 temp >>= 31; //16+31-16 = 31 bits
10
11 return (int32_t)temp;
12}
13
14/*
15 * Fast integer square root adapted from algorithm,
16 * Martin Guy @ UKC, June 1985.
17 * Originally from a book on programming abaci by Mr C. Woo.
18 * This is taken from :
19 * http://wiki.forum.nokia.com/index.php/How_to_use_fixed_point_maths#How_to_get_square_root_for_integers
20 * with a added shift up of the result by 8 bits to return result in 16.16 fixed-point representation.
21 */
22inline int32_t fastSqrt(int32_t n)
23{
24 /*
25 * Logically, these are unsigned.
26 * We need the sign bit to test
27 * whether (op - res - one) underflowed.
28 */
29 int32_t op, res, one;
30 op = n;
31 res = 0;
32 /* "one" starts at the highest power of four <= than the argument. */
33 one = 1 << 30; /* second-to-top bit set */
34 while (one > op) one >>= 2;
35 while (one != 0)
36 {
37 if (op >= res + one)
38 {
39 op = op - (res + one);
40 res = res + (one<<1);
41 }
42 res >>= 1;
43 one >>= 2;
44 }
45 return(res << 8);
46}
47
48inline int32_t fixmul16(int32_t x, int32_t y)
49{
50 int64_t temp;
51 temp = x;
52 temp *= y;
53
54 temp >>= 16;
55
56 return (int32_t)temp;
57}
58
59inline int32_t fixdiv16(int32_t x, int32_t y)
60{
61 int64_t temp;
62 temp = x << 16;
63 temp /= y;
64
65 return (int32_t)temp;
66}