/***************************************************************************
 *             __________               __   ___.
 *   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.
 *
 ****************************************************************************/

#ifndef _FIXEDPOINT_H
#define _FIXEDPOINT_H

#include <inttypes.h>

/** 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

#define DIV64(x, y, z) (long)(((long long)(x) << (z))/(y))


/** 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 a, unsigned int fracbits);
long cos_int(int val);
long sin_int(int val);
long flog(int x);

#endif