spl_inl.h

/*
 *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */


// This header file includes the inline functions in
// the fix point signal processing library.

#ifndef WEBRTC_SPL_SPL_INL_H_
#define WEBRTC_SPL_SPL_INL_H_

#ifdef WEBRTC_SPL_INLINE_CALLS

#ifdef WEBRTC_ANDROID

__asm (
   // On Android gcc compiler, the clz instruction is not supported with a
   // target smaller than armv7, despite it being legal for armv5+.
"   .arch armv7-a\n"
//"   clz     %0, %1  \n"
//"=r"    (leading_zeroes)
//"r"     (data)
);

WEBRTC_INLINE WebRtc_Word32 WEBRTC_SPL_MUL(WebRtc_Word32 a, WebRtc_Word32 b)
{
    WebRtc_Word32 tmp;
    __asm__("smmul %0, %1, %2":"=r"(tmp):"r"(a), "r"(b)); //changed mul to smmul.
    return tmp;
}

WEBRTC_INLINE WebRtc_Word32 WEBRTC_SPL_MUL_16_32_RSFT16(WebRtc_Word16 a,
                                                        WebRtc_Word32 b)
{
    WebRtc_Word32 tmp;
    __asm__("smulwb %0, %1, %2":"=r"(tmp):"r"(b), "r"(a));
    return tmp;
}

WEBRTC_INLINE WebRtc_Word32 WEBRTC_SPL_MUL_32_32_RSFT32(WebRtc_Word16 a,
                                                      WebRtc_Word16 b,
                                                      WebRtc_Word32 c)
{
    WebRtc_Word32 tmp;
    __asm__("pkhbt %0, %1, %2, lsl #16" : "=r"(tmp) : "r"(b), "r"(a));
    __asm__("smmul %0, %1, %2":"=r"(tmp):"r"(tmp), "r"(c));
    return tmp;
}

WEBRTC_INLINE WebRtc_Word32 WEBRTC_SPL_MUL_32_32_RSFT32BI(
        WebRtc_Word32 a,
        WebRtc_Word32 b)
{
    WebRtc_Word32 tmp;
    __asm__("smmul %0, %1, %2":"=r"(tmp):"r"(a), "r"(b));
    return tmp;
}

WEBRTC_INLINE WebRtc_Word32 WEBRTC_SPL_MUL_16_16(WebRtc_Word16 a,
                                                 WebRtc_Word16 b)
{
    WebRtc_Word32 tmp;
    __asm__("smulbb %0, %1, %2":"=r"(tmp):"r"(a), "r"(b));
    return tmp;
}

WEBRTC_INLINE WebRtc_Word16 WebRtcSpl_AddSatW16(WebRtc_Word16 a,
                                                WebRtc_Word16 b)
{
    WebRtc_Word32 s_sum;

    __asm__("qadd %0, %1, %2":"=r"(s_sum):"r"(a), "r"(b));

    return (WebRtc_Word16) s_sum;
}

WEBRTC_INLINE WebRtc_Word32 WebRtcSpl_AddSatW32(WebRtc_Word32 l_var1,
                                                WebRtc_Word32 l_var2)
{
    WebRtc_Word32 l_sum;

    __asm__("qadd %0, %1, %2":"=r"(l_sum):"r"(l_var1), "r"(l_var2));

    return l_sum;
}

WEBRTC_INLINE WebRtc_Word16 WebRtcSpl_SubSatW16(WebRtc_Word16 var1,
                                                WebRtc_Word16 var2)
{
    WebRtc_Word32 s_sub;

    __asm__("qsub %0, %1, %2":"=r"(s_sub):"r"(var1), "r"(var2));

    return (WebRtc_Word16)s_sub;
}

WEBRTC_INLINE WebRtc_Word32 WebRtcSpl_SubSatW32(WebRtc_Word32 l_var1,
                                                WebRtc_Word32 l_var2)
{
    WebRtc_Word32 l_sub;

    __asm__("qsub %0, %1, %2":"=r"(l_sub):"r"(l_var1), "r"(l_var2));

    return l_sub;
}

WEBRTC_INLINE WebRtc_Word16 WebRtcSpl_GetSizeInBits(WebRtc_UWord32 n)
{
    WebRtc_Word32 tmp;

    __asm__("clz %0, %1":"=r"(tmp):"r"(n));

    return (WebRtc_Word16)(32 - tmp);
}

WEBRTC_INLINE int WebRtcSpl_NormW32(WebRtc_Word32 a)
{
    WebRtc_Word32 tmp;

    if (a <= 0) a ^= 0xFFFFFFFF;

    __asm__("clz %0, %1":"=r"(tmp):"r"(a));

    return tmp - 1;
}

WEBRTC_INLINE int WebRtcSpl_NormW16(WebRtc_Word16 a)
{
    int zeros;

    if (a <= 0) a ^= 0xFFFF;

    if (!(0xFF80 & a)) zeros = 8; else zeros = 0;
    if (!(0xF800 & (a << zeros))) zeros += 4;
    if (!(0xE000 & (a << zeros))) zeros += 2;
    if (!(0xC000 & (a << zeros))) zeros += 1;

    return zeros;
}

WEBRTC_INLINE int WebRtcSpl_NormU32(WebRtc_UWord32 a)
{
    int tmp;

    if (a == 0) return 0;

    __asm__("clz %0, %1":"=r"(tmp):"r"(a));

    return tmp;
}

#else

WEBRTC_INLINE WebRtc_Word16 WebRtcSpl_AddSatW16(WebRtc_Word16 a,
                                                WebRtc_Word16 b)
{
    WebRtc_Word32 s_sum = (WebRtc_Word32) a + (WebRtc_Word32) b;

    if (s_sum > WEBRTC_SPL_WORD16_MAX)
    s_sum = WEBRTC_SPL_WORD16_MAX;
    else if (s_sum < WEBRTC_SPL_WORD16_MIN)
    s_sum = WEBRTC_SPL_WORD16_MIN;

    return (WebRtc_Word16)s_sum;
}

WEBRTC_INLINE WebRtc_Word32 WebRtcSpl_AddSatW32(WebRtc_Word32 l_var1,
                                                WebRtc_Word32 l_var2)
{
    WebRtc_Word32 l_sum;

    // perform long addition
    l_sum = l_var1 + l_var2;

    // check for under or overflow
    if (WEBRTC_SPL_IS_NEG (l_var1))
    {
        if (WEBRTC_SPL_IS_NEG (l_var2) && !WEBRTC_SPL_IS_NEG (l_sum))
        {
            l_sum = (WebRtc_Word32)0x80000000;
        }
    }
    else
    {
        if (!WEBRTC_SPL_IS_NEG (l_var2) && WEBRTC_SPL_IS_NEG (l_sum))
        {
            l_sum = (WebRtc_Word32)0x7FFFFFFF;
        }
    }

    return l_sum;
}

WEBRTC_INLINE WebRtc_Word16 WebRtcSpl_SubSatW16( WebRtc_Word16 var1,
                                                 WebRtc_Word16 var2)
{
    WebRtc_Word32 l_diff;
    WebRtc_Word16 s_diff;

    // perform subtraction
    l_diff = (WebRtc_Word32)var1 - (WebRtc_Word32)var2;

    // default setting
    s_diff = (WebRtc_Word16) l_diff;

    // check for overflow
    if (l_diff > (WebRtc_Word32)32767)
    s_diff = (WebRtc_Word16)32767;

    // check for underflow
    if (l_diff < (WebRtc_Word32)-32768)
    s_diff = (WebRtc_Word16)-32768;

    return s_diff;
}

WEBRTC_INLINE WebRtc_Word32 WebRtcSpl_SubSatW32(WebRtc_Word32 l_var1,
                                                WebRtc_Word32 l_var2)
{
    WebRtc_Word32 l_diff;

    // perform subtraction
    l_diff = l_var1 - l_var2;

    // check for underflow
    if ((l_var1 < 0) && (l_var2 > 0) && (l_diff > 0))
    l_diff = (WebRtc_Word32)0x80000000;
    // check for overflow
    if ((l_var1 > 0) && (l_var2 < 0) && (l_diff < 0))
    l_diff = (WebRtc_Word32)0x7FFFFFFF;

    return l_diff;
}

WEBRTC_INLINE WebRtc_Word16 WebRtcSpl_GetSizeInBits(WebRtc_UWord32 n)
{

    int bits;

    if ((0xFFFF0000 & n)) bits = 16; else bits = 0;
    if ((0x0000FF00 & (n >> bits))) bits += 8;
    if ((0x000000F0 & (n >> bits))) bits += 4;
    if ((0x0000000C & (n >> bits))) bits += 2;
    if ((0x00000002 & (n >> bits))) bits += 1;
    if ((0x00000001 & (n >> bits))) bits += 1;

    return bits;
}

WEBRTC_INLINE int WebRtcSpl_NormW32(WebRtc_Word32 a)
{
    int zeros;

    if (a <= 0) a ^= 0xFFFFFFFF;

    if (!(0xFFFF8000 & a)) zeros = 16; else zeros = 0;
    if (!(0xFF800000 & (a << zeros))) zeros += 8;
    if (!(0xF8000000 & (a << zeros))) zeros += 4;
    if (!(0xE0000000 & (a << zeros))) zeros += 2;
    if (!(0xC0000000 & (a << zeros))) zeros += 1;

    return zeros;
}

WEBRTC_INLINE int WebRtcSpl_NormW16(WebRtc_Word16 a)
{
    int zeros;

    if (a <= 0) a ^= 0xFFFF;

    if (!(0xFF80 & a)) zeros = 8; else zeros = 0;
    if (!(0xF800 & (a << zeros))) zeros += 4;
    if (!(0xE000 & (a << zeros))) zeros += 2;
    if (!(0xC000 & (a << zeros))) zeros += 1;

    return zeros;
}

WEBRTC_INLINE int WebRtcSpl_NormU32(WebRtc_UWord32 a)
{
    int zeros;

    if (a == 0) return 0;

    if (!(0xFFFF0000 & a)) zeros = 16; else zeros = 0;
    if (!(0xFF000000 & (a << zeros))) zeros += 8;
    if (!(0xF0000000 & (a << zeros))) zeros += 4;
    if (!(0xC0000000 & (a << zeros))) zeros += 2;
    if (!(0x80000000 & (a << zeros))) zeros += 1;

    return zeros;
}

#endif // WEBRTC_ANDROID
#endif // WEBRTC_SPL_INLINE_CALLS
#endif // WEBRTC_SPL_SPL_INL_H_