blob: 45a827af15ba17327ae06d9e7127466f62b9b7d4 [file] [log] [blame]
//#include "asf.h"
#include "wmadec.h"
#include "wmafixed.h"
#include <codecs.h>
fixed64 IntTo64(int x){
fixed64 res = 0;
unsigned char *p = (unsigned char *)&res;
#ifdef ROCKBOX_BIG_ENDIAN
p[5] = x & 0xff;
p[4] = (x & 0xff00)>>8;
p[3] = (x & 0xff0000)>>16;
p[2] = (x & 0xff000000)>>24;
#else
p[2] = x & 0xff;
p[3] = (x & 0xff00)>>8;
p[4] = (x & 0xff0000)>>16;
p[5] = (x & 0xff000000)>>24;
#endif
return res;
}
int IntFrom64(fixed64 x)
{
int res = 0;
unsigned char *p = (unsigned char *)&x;
#ifdef ROCKBOX_BIG_ENDIAN
res = p[5] | (p[4]<<8) | (p[3]<<16) | (p[2]<<24);
#else
res = p[2] | (p[3]<<8) | (p[4]<<16) | (p[5]<<24);
#endif
return res;
}
fixed32 Fixed32From64(fixed64 x)
{
return x & 0xFFFFFFFF;
}
fixed64 Fixed32To64(fixed32 x)
{
return (fixed64)x;
}
/*
Fixed precision multiply code.
*/
/*Sign-15.16 format */
#ifdef CPU_ARM
/* these are defines in wmafixed.h*/
#elif defined(CPU_COLDFIRE)
inline int32_t fixmul32(int32_t x, int32_t y)
{
#if PRECISION != 16
#warning Coldfire fixmul32() only works for PRECISION == 16
#endif
int32_t t1;
asm (
"mac.l %[x], %[y], %%acc0 \n" /* multiply */
"mulu.l %[y], %[x] \n" /* get lower half, avoid emac stall */
"movclr.l %%acc0, %[t1] \n" /* get higher half */
"lsr.l #1, %[t1] \n"
"move.w %[t1], %[x] \n"
"swap %[x] \n"
: /* outputs */
[t1]"=&d"(t1),
[x] "+d" (x)
: /* inputs */
[y] "d" (y)
);
return x;
}
#else
fixed32 fixmul32(fixed32 x, fixed32 y)
{
fixed64 temp;
temp = x;
temp *= y;
temp >>= PRECISION;
return (fixed32)temp;
}
/*
Special fixmul32 that does a 16.16 x 1.31 multiply that returns a 16.16 value.
this is needed because the fft constants are all normalized to be less then 1
and can't fit into a 16 bit number without excessive rounding
*/
fixed32 fixmul32b(fixed32 x, fixed32 y)
{
fixed64 temp;
temp = x;
temp *= y;
temp >>= 31; //16+31-16 = 31 bits
return (fixed32)temp;
}
#endif
/*
Not performance senstitive code here
*/
fixed64 fixmul64byfixed(fixed64 x, fixed32 y)
{
//return x * y;
return (x * y);
// return (fixed64) fixmul32(Fixed32From64(x),y);
}
fixed32 fixdiv32(fixed32 x, fixed32 y)
{
fixed64 temp;
if(x == 0)
return 0;
if(y == 0)
return 0x7fffffff;
temp = x;
temp <<= PRECISION;
return (fixed32)(temp / y);
}
fixed64 fixdiv64(fixed64 x, fixed64 y)
{
fixed64 temp;
if(x == 0)
return 0;
if(y == 0)
return 0x07ffffffffffffffLL;
temp = x;
temp <<= PRECISION64;
return (fixed64)(temp / y);
}
fixed32 fixsqrt32(fixed32 x)
{
unsigned long r = 0, s, v = (unsigned long)x;
#define STEP(k) s = r + (1 << k * 2); r >>= 1; \
if (s <= v) { v -= s; r |= (1 << k * 2); }
STEP(15);
STEP(14);
STEP(13);
STEP(12);
STEP(11);
STEP(10);
STEP(9);
STEP(8);
STEP(7);
STEP(6);
STEP(5);
STEP(4);
STEP(3);
STEP(2);
STEP(1);
STEP(0);
return (fixed32)(r << (PRECISION / 2));
}
/* Inverse gain of circular cordic rotation in s0.31 format. */
static const long cordic_circular_gain = 0xb2458939; /* 0.607252929 */
/* Table of values of atan(2^-i) in 0.32 format fractions of pi where pi = 0xffffffff / 2 */
static const unsigned long atan_table[] = {
0x1fffffff, /* +0.785398163 (or pi/4) */
0x12e4051d, /* +0.463647609 */
0x09fb385b, /* +0.244978663 */
0x051111d4, /* +0.124354995 */
0x028b0d43, /* +0.062418810 */
0x0145d7e1, /* +0.031239833 */
0x00a2f61e, /* +0.015623729 */
0x00517c55, /* +0.007812341 */
0x0028be53, /* +0.003906230 */
0x00145f2e, /* +0.001953123 */
0x000a2f98, /* +0.000976562 */
0x000517cc, /* +0.000488281 */
0x00028be6, /* +0.000244141 */
0x000145f3, /* +0.000122070 */
0x0000a2f9, /* +0.000061035 */
0x0000517c, /* +0.000030518 */
0x000028be, /* +0.000015259 */
0x0000145f, /* +0.000007629 */
0x00000a2f, /* +0.000003815 */
0x00000517, /* +0.000001907 */
0x0000028b, /* +0.000000954 */
0x00000145, /* +0.000000477 */
0x000000a2, /* +0.000000238 */
0x00000051, /* +0.000000119 */
0x00000028, /* +0.000000060 */
0x00000014, /* +0.000000030 */
0x0000000a, /* +0.000000015 */
0x00000005, /* +0.000000007 */
0x00000002, /* +0.000000004 */
0x00000001, /* +0.000000002 */
0x00000000, /* +0.000000001 */
0x00000000, /* +0.000000000 */
};
/*
Below here functions do not use standard fixed precision!
*/
/**
* Implements sin and cos using CORDIC rotation.
*
* @param phase has range from 0 to 0xffffffff, representing 0 and
* 2*pi respectively.
* @param cos return address for cos
* @return sin of phase, value is a signed value from LONG_MIN to LONG_MAX,
* representing -1 and 1 respectively.
*
* Gives at least 24 bits precision (last 2-8 bits or so are probably off)
*/
long fsincos(unsigned long phase, fixed32 *cos)
{
int32_t x, x1, y, y1;
unsigned long z, z1;
int i;
/* Setup initial vector */
x = cordic_circular_gain;
y = 0;
z = phase;
/* The phase has to be somewhere between 0..pi for this to work right */
if (z < 0xffffffff / 4) {
/* z in first quadrant, z += pi/2 to correct */
x = -x;
z += 0xffffffff / 4;
} else if (z < 3 * (0xffffffff / 4)) {
/* z in third quadrant, z -= pi/2 to correct */
z -= 0xffffffff / 4;
} else {
/* z in fourth quadrant, z -= 3pi/2 to correct */
x = -x;
z -= 3 * (0xffffffff / 4);
}
/* Each iteration adds roughly 1-bit of extra precision */
for (i = 0; i < 31; i++) {
x1 = x >> i;
y1 = y >> i;
z1 = atan_table[i];
/* Decided which direction to rotate vector. Pivot point is pi/2 */
if (z >= 0xffffffff / 4) {
x -= y1;
y += x1;
z -= z1;
} else {
x += y1;
y -= x1;
z += z1;
}
}
if (cos)
*cos = x;
return y;
}
/*
Old trig functions. Still used in 1 place each.
*/
fixed32 fixsin32(fixed32 x)
{
fixed64 x2, temp;
int sign = 1;
if(x < 0)
{
sign = -1;
x = -x;
}
while (x > 0x19220)
{
x -= M_PI_F;
sign = -sign;
}
if (x > 0x19220)
{
x = M_PI_F - x;
}
x2 = (fixed64)x * x;
x2 >>= PRECISION;
if(sign != 1)
{
x = -x;
}
/**
temp = ftofix32(-.0000000239f) * x2;
temp >>= PRECISION;
**/
temp = 0; // PJJ
//temp = (temp + 0x0) * x2; //MGG: this can't possibly do anything?
//temp >>= PRECISION;
temp = (temp - 0xd) * x2;
temp >>= PRECISION;
temp = (temp + 0x222) * x2;
temp >>= PRECISION;
temp = (temp - 0x2aab) * x2;
temp >>= PRECISION;
temp += 0x10000;
temp = temp * x;
temp >>= PRECISION;
return (fixed32)(temp);
}
fixed32 fixcos32(fixed32 x)
{
return fixsin32(x - (M_PI_F>>1))*-1;
}