aacassembly.h

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/* ***** BEGIN LICENSE BLOCK *****
 * Source last modified: $Id: aacassembly.h,v 1.9 2007/02/28 07:10:21 gahluwalia Exp $
 *
 * Portions Copyright (c) 1995-2005 RealNetworks, Inc. All Rights Reserved.
 *
 * The contents of this file, and the files included with this file,
 * are subject to the current version of the RealNetworks Public
 * Source License (the "RPSL") available at
 * http://www.helixcommunity.org/content/rpsl unless you have licensed
 * the file under the current version of the RealNetworks Community
 * Source License (the "RCSL") available at
 * http://www.helixcommunity.org/content/rcsl, in which case the RCSL
 * will apply. You may also obtain the license terms directly from
 * RealNetworks.  You may not use this file except in compliance with
 * the RPSL or, if you have a valid RCSL with RealNetworks applicable
 * to this file, the RCSL.  Please see the applicable RPSL or RCSL for
 * the rights, obligations and limitations governing use of the
 * contents of the file.
 *
 * This file is part of the Helix DNA Technology. RealNetworks is the
 * developer of the Original Code and owns the copyrights in the
 * portions it created.
 *
 * This file, and the files included with this file, is distributed
 * and made available on an 'AS IS' basis, WITHOUT WARRANTY OF ANY
 * KIND, EITHER EXPRESS OR IMPLIED, AND REALNETWORKS HEREBY DISCLAIMS
 * ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET
 * ENJOYMENT OR NON-INFRINGEMENT.
 *
 * Technology Compatibility Kit Test Suite(s) Location:
 *    http://www.helixcommunity.org/content/tck
 *
 * Contributor(s):
 *
 * ***** END LICENSE BLOCK ***** */

/**************************************************************************************
 * Fixed-point HE-AAC decoder
 * Jon Recker (jrecker@real.com)
 * February 2005
 *
 * aacassembly.h - inline assembly language functions and prototypes
 *
 * MULSHIFT32(x, y)             signed multiply of two 32-bit integers (x and y),
 *                            returns top 32-bits of 64-bit result
 * CLIPTOSHORT(x)                       convert 32-bit integer to 16-bit short,
 *                            clipping to [-32768, 32767]
 * FASTABS(x)               branchless absolute value of signed integer x
 * CLZ(x)                   count leading zeros on signed integer x
 * MADD64(sum64, x, y)          64-bit multiply accumulate: sum64 += (x*y)
 **************************************************************************************/

#ifndef _ASSEMBLY_H
#define _ASSEMBLY_H

#include "aacdec.h"

/* toolchain:           ARM gcc
 * target architecture: ARM v7-m cortex-m
 */
#if defined(__GNUC__) && (defined(ARM) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7EM__))

typedef long long Word64;

typedef union _U64 
{
    Word64 w64;
    struct 
    {
        unsigned int lo32;
        signed int   hi32;
    }r;
} U64;

#define CLIPTOSHORT(x)    __SSAT(x,16)

#define CLZ(x)            __CLZ(x)

static inline int MULSHIFT32(int x, int y)
{
    int zlow;
    __asm__ volatile ("smull %0,%1,%2,%3" : "=&r" (zlow), "=r" (y) : "r" (x), "1" (y) : "cc");
    return y;
}

static inline int FASTABS(int x)
{
    int sign;
    sign = x >> (sizeof(int) * 8 - 1);
    x ^= sign;
    x -= sign;
    return x;
}

static inline Word64 MADD64(Word64 sum64, int x, int y)
{
    U64 u;
    u.w64 = sum64;
    __asm__ volatile ("smlal %0,%1,%2,%3" : "+&r" (u.r.lo32), "+&r" (u.r.hi32) : "r" (x), "r" (y) : "cc");
    return u.w64;
}

/* toolchain:           iar iccarm
 * target architecture: ARM v7-m cortex-m
 */
#elif defined(__ICCARM__)

typedef long long Word64;

typedef union _U64 
{
    Word64 w64;
    struct 
    {
        unsigned int lo32;
        signed int   hi32;
    }r;
} U64;

#define CLIPTOSHORT(x)    __SSAT(x,16)

#define CLZ(x)            __CLZ(x)

static inline int MULSHIFT32(int x, int y)
{
    int z;
    z = (long long)x * (long long)y >> 32;
    return z;
}

static inline int FASTABS(int x)
{
    int sign;
    sign = x >> (sizeof(int) * 8 - 1);
    x ^= sign;
    x -= sign;
    return x;
}

static inline long long MADD64(long long sum, int x, int y)
{
    return (sum +(long long)x * y);
}

#else

typedef long long Word64;

typedef union _U64
{
    Word64 w64;
    struct
    {
        unsigned int lo32;
        signed int   hi32;
    }r;
} U64;

static inline int CLZ(int x)
{
    int numZeros;

    if(!x)
        return 32;

    numZeros = 1;
    if(!((unsigned int)x >> 16)) { numZeros += 16; x <<= 16;}
    if(!((unsigned int)x >> 24)) { numZeros += 8; x <<= 8;}
    if(!((unsigned int)x >> 28)) { numZeros += 4; x <<= 4;}
    if(!((unsigned int)x >> 30)) { numZeros += 2; x <<= 2;}

    numZeros -= ((unsigned int)x >> 31);

    return numZeros;
}


static inline int CLIPTOSHORT(int x)
{
    int sign;

    sign = x>>31;
    if(sign != (x >> 15))
        x = sign ^ ((1 << 15)-1);

    return x;
}


static inline int MULSHIFT32(int x, int y)
{
    int z;
    z = (long long)x * (long long)y >> 32;
    return z;
}

static inline int FASTABS(int x)
{
    int sign;
    sign = x >> (sizeof(int) * 8 - 1);
    x ^= sign;
    x -= sign;
    return x;
}

static inline long long MADD64(long long sum, int x, int y)
{
    return (sum +(long long)x * y);
}

#endif  /* platforms */

#endif /* _ASSEMBLY_H */