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Make those functions actually inline. Around 20% speedup on coldfire, 10% speedup on arm.

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@22344 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Jens Arnold 2009-08-16 12:41:04 +00:00
parent 90ea3e9716
commit 3d6f86eb2f
3 changed files with 65 additions and 71 deletions
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1
apps/codecs/libatrac/SOURCES
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@ -1,3 +1,2 @@
atrac3.c
fixp_math.c
../lib/ffmpeg_bitstream.c

66
apps/codecs/libatrac/fixp_math.c
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@ -1,66 +0,0 @@
#include "fixp_math.h"
inline int32_t fixmul31(int32_t x, int32_t y)
{
int64_t temp;
temp = x;
temp *= y;
temp >>= 31; //16+31-16 = 31 bits
return (int32_t)temp;
}
/*
* Fast integer square root adapted from algorithm,
* Martin Guy @ UKC, June 1985.
* Originally from a book on programming abaci by Mr C. Woo.
* This is taken from :
* http://wiki.forum.nokia.com/index.php/How_to_use_fixed_point_maths#How_to_get_square_root_for_integers
* with a added shift up of the result by 8 bits to return result in 16.16 fixed-point representation.
*/
inline int32_t fastSqrt(int32_t n)
{
/*
* Logically, these are unsigned.
* We need the sign bit to test
* whether (op - res - one) underflowed.
*/
int32_t op, res, one;
op = n;
res = 0;
/* "one" starts at the highest power of four <= than the argument. */
one = 1 << 30; /* second-to-top bit set */
while (one > op) one >>= 2;
while (one != 0)
{
if (op >= res + one)
{
op = op - (res + one);
res = res + (one<<1);
}
res >>= 1;
one >>= 2;
}
return(res << 8);
}
inline int32_t fixmul16(int32_t x, int32_t y)
{
int64_t temp;
temp = x;
temp *= y;
temp >>= 16;
return (int32_t)temp;
}
inline int32_t fixdiv16(int32_t x, int32_t y)
{
int64_t temp;
temp = x << 16;
temp /= y;
return (int32_t)temp;
}

69
apps/codecs/libatrac/fixp_math.h
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@ -9,7 +9,68 @@
#define fix31tof64(x) (float)((float)(x) / (float)(1 << 31))
/* Fixed point math routines for use in atrac3.c */
inline int32_t fixmul16(int32_t x, int32_t y);
inline int32_t fixmul31(int32_t x, int32_t y);
inline int32_t fixdiv16(int32_t x, int32_t y);
inline int32_t fastSqrt(int32_t n);
static inline int32_t fixmul16(int32_t x, int32_t y)
{
int64_t temp;
temp = x;
temp *= y;
temp >>= 16;
return (int32_t)temp;
}
static inline int32_t fixmul31(int32_t x, int32_t y)
{
int64_t temp;
temp = x;
temp *= y;
temp >>= 31; //16+31-16 = 31 bits
return (int32_t)temp;
}
static inline int32_t fixdiv16(int32_t x, int32_t y)
{
int64_t temp;
temp = x << 16;
temp /= y;
return (int32_t)temp;
}
/*
* Fast integer square root adapted from algorithm,
* Martin Guy @ UKC, June 1985.
* Originally from a book on programming abaci by Mr C. Woo.
* This is taken from :
* http://wiki.forum.nokia.com/index.php/How_to_use_fixed_point_maths#How_to_get_square_root_for_integers
* with a added shift up of the result by 8 bits to return result in 16.16 fixed-point representation.
*/
static inline int32_t fastSqrt(int32_t n)
{
/*
* Logically, these are unsigned.
* We need the sign bit to test
* whether (op - res - one) underflowed.
*/
int32_t op, res, one;
op = n;
res = 0;
/* "one" starts at the highest power of four <= than the argument. */
one = 1 << 30; /* second-to-top bit set */
while (one > op) one >>= 2;
while (one != 0)
{
if (op >= res + one)
{
op = op - (res + one);
res = res + (one<<1);
}
res >>= 1;
one >>= 2;
}
return(res << 8);
}