4710a32800
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21633 a1c6a512-1295-4272-9138-f99709370657
197 lines
6.7 KiB
C
197 lines
6.7 KiB
C
/***************************************************************************
|
|
* __________ __ ___.
|
|
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
|
|
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
|
|
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
|
|
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
|
|
* \/ \/ \/ \/ \/
|
|
* $Id: fixedpoint.h -1 $
|
|
*
|
|
* Copyright (C) 2006 Jens Arnold
|
|
*
|
|
* Fixed point library for plugins
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2
|
|
* of the License, or (at your option) any later version.
|
|
*
|
|
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
|
|
* KIND, either express or implied.
|
|
*
|
|
****************************************************************************/
|
|
|
|
/** FIXED POINT MATH ROUTINES - USAGE
|
|
*
|
|
* - x and y arguments are fixed point integers
|
|
* - fracbits is the number of fractional bits in the argument(s)
|
|
* - functions return long fixed point integers with the specified number
|
|
* of fractional bits unless otherwise specified
|
|
*
|
|
* Multiply two fixed point numbers:
|
|
* fp_mul(x, y, fracbits)
|
|
*
|
|
* Shortcut: Multiply two fixed point numbers with 31 fractional bits:
|
|
* fp31_mul(x, y)
|
|
*
|
|
* Shortcut: Multiply two fixed point numbers with 31 fractional bits,
|
|
* then shift left by z bits:
|
|
* fp31_mulshl(x, y, z)
|
|
* NOTE: z must be in the range 1-8 on Coldfire targets.
|
|
*
|
|
* Divide two fixed point numbers:
|
|
* fp_div(x, y, fracbits)
|
|
*
|
|
* Take square root of a fixed point number:
|
|
* fp_sqrt(x, fracbits)
|
|
*
|
|
* Calculate sin and cos of an angle:
|
|
* fp_sincos(phase, *cos)
|
|
* where phase is a 32 bit unsigned integer with 0 representing 0
|
|
* and 0xFFFFFFFF representing 2*pi, and *cos is the address to
|
|
* a long signed integer. Value returned is a long signed integer
|
|
* from LONG_MIN to LONG_MAX, representing -1 to 1 respectively.
|
|
* That is, value is a fixed point integer with 31 fractional bits.
|
|
*
|
|
* Calculate sin or cos of an angle (very fast, from a table):
|
|
* fp14_sin(angle)
|
|
* fp14_cos(angle)
|
|
* where angle is a non-fixed point integer in degrees. Value
|
|
* returned is a fixed point integer with 14 fractional bits.
|
|
*
|
|
* Calculate decibel equivalent of a gain factor:
|
|
* fp_decibels(factor, fracbits)
|
|
* where fracbits is in the range 12 to 22 (higher is better),
|
|
* and factor is a positive fixed point integer.
|
|
*
|
|
* Calculate factor equivalent of a decibel value:
|
|
* fp_factor(decibels, fracbits)
|
|
* where fracbits is in the range 12 to 22 (lower is better),
|
|
* and decibels is a fixed point integer.
|
|
*/
|
|
|
|
#ifndef _FIXEDPOINT_H
|
|
#define _FIXEDPOINT_H
|
|
|
|
#include <inttypes.h>
|
|
|
|
/* Redefine function names, making sure legacy code is usable */
|
|
#define fp31_mul(x, y) FRACMUL(x, y)
|
|
#define fp31_mulshl(x, y, z) FRACMUL_SHL(x, y, z)
|
|
#define fp_div(x, y, z) DIV64(x, y, z)
|
|
#define fp_sqrt(x, y) fsqrt(x, y)
|
|
#define fp_sincos(x, y) fsincos(x, y)
|
|
#define fp14_sin(x) sin_int(x)
|
|
#define fp14_cos(x) cos_int(x)
|
|
#define fp16_log(x) flog(x)
|
|
|
|
|
|
#define fp_mul(x, y, z) (long)((((long long)(x)) * ((long long)(y))) >> (z))
|
|
#define DIV64(x, y, z) (long)((((long long)(x)) << (z)) / ((long long)(y)))
|
|
|
|
/** TAKEN FROM apps/dsp.h */
|
|
/* A bunch of fixed point assembler helper macros */
|
|
#if defined(CPU_COLDFIRE)
|
|
/* These macros use the Coldfire EMAC extension and need the MACSR flags set
|
|
* to fractional mode with no rounding.
|
|
*/
|
|
|
|
/* Multiply two S.31 fractional integers and return the sign bit and the
|
|
* 31 most significant bits of the result.
|
|
*/
|
|
#define FRACMUL(x, y) \
|
|
({ \
|
|
long t; \
|
|
asm ("mac.l %[a], %[b], %%acc0\n\t" \
|
|
"movclr.l %%acc0, %[t]\n\t" \
|
|
: [t] "=r" (t) : [a] "r" (x), [b] "r" (y)); \
|
|
t; \
|
|
})
|
|
|
|
/* Multiply two S.31 fractional integers, and return the 32 most significant
|
|
* bits after a shift left by the constant z. NOTE: Only works for shifts of
|
|
* 1 to 8 on Coldfire!
|
|
*/
|
|
#define FRACMUL_SHL(x, y, z) \
|
|
({ \
|
|
long t, t2; \
|
|
asm ("mac.l %[a], %[b], %%acc0\n\t" \
|
|
"moveq.l %[d], %[t]\n\t" \
|
|
"move.l %%accext01, %[t2]\n\t" \
|
|
"and.l %[mask], %[t2]\n\t" \
|
|
"lsr.l %[t], %[t2]\n\t" \
|
|
"movclr.l %%acc0, %[t]\n\t" \
|
|
"asl.l %[c], %[t]\n\t" \
|
|
"or.l %[t2], %[t]\n\t" \
|
|
: [t] "=&d" (t), [t2] "=&d" (t2) \
|
|
: [a] "r" (x), [b] "r" (y), [mask] "d" (0xff), \
|
|
[c] "i" ((z)), [d] "i" (8 - (z))); \
|
|
t; \
|
|
})
|
|
|
|
#elif defined(CPU_ARM)
|
|
|
|
/* Multiply two S.31 fractional integers and return the sign bit and the
|
|
* 31 most significant bits of the result.
|
|
*/
|
|
#define FRACMUL(x, y) \
|
|
({ \
|
|
long t, t2; \
|
|
asm ("smull %[t], %[t2], %[a], %[b]\n\t" \
|
|
"mov %[t2], %[t2], asl #1\n\t" \
|
|
"orr %[t], %[t2], %[t], lsr #31\n\t" \
|
|
: [t] "=&r" (t), [t2] "=&r" (t2) \
|
|
: [a] "r" (x), [b] "r" (y)); \
|
|
t; \
|
|
})
|
|
|
|
/* Multiply two S.31 fractional integers, and return the 32 most significant
|
|
* bits after a shift left by the constant z.
|
|
*/
|
|
#define FRACMUL_SHL(x, y, z) \
|
|
({ \
|
|
long t, t2; \
|
|
asm ("smull %[t], %[t2], %[a], %[b]\n\t" \
|
|
"mov %[t2], %[t2], asl %[c]\n\t" \
|
|
"orr %[t], %[t2], %[t], lsr %[d]\n\t" \
|
|
: [t] "=&r" (t), [t2] "=&r" (t2) \
|
|
: [a] "r" (x), [b] "r" (y), \
|
|
[c] "M" ((z) + 1), [d] "M" (31 - (z))); \
|
|
t; \
|
|
})
|
|
|
|
#else
|
|
|
|
#define FRACMUL(x, y) (long) (((((long long) (x)) * ((long long) (y))) >> 31))
|
|
#define FRACMUL_SHL(x, y, z) \
|
|
((long)(((((long long) (x)) * ((long long) (y))) >> (31 - (z)))))
|
|
|
|
#endif
|
|
|
|
/** TAKEN FROM ORIGINAL fixedpoint.h */
|
|
/* fast unsigned multiplication (16x16bit->32bit or 32x32bit->32bit,
|
|
* whichever is faster for the architecture) */
|
|
#ifdef CPU_ARM
|
|
#define FMULU(a, b) ((uint32_t) (((uint32_t) (a)) * ((uint32_t) (b))))
|
|
#else /* SH1, coldfire */
|
|
#define FMULU(a, b) ((uint32_t) (((uint16_t) (a)) * ((uint16_t) (b))))
|
|
#endif
|
|
|
|
long fsincos(unsigned long phase, long *cos);
|
|
long fsqrt(long x, unsigned int fracbits);
|
|
long sin_int(int val);
|
|
long cos_int(int val);
|
|
long flog(int x);
|
|
|
|
|
|
/** MODIFIED FROM replaygain.c */
|
|
#define FP_INF (0x7fffffff)
|
|
#define FP_NEGINF -(0x7fffffff)
|
|
|
|
/* fracbits in range 12 - 22 work well. Higher is better for
|
|
* calculating dB, lower is better for calculating ratio.
|
|
*/
|
|
long fp_decibels(unsigned long factor, unsigned int fracbits);
|
|
long fp_factor(long decibels, unsigned int fracbits);
|
|
|
|
#endif
|