// Copyright (C) 2016 The Qt Company Ltd.

// Copyright (C) 2016 Intel Corporation.

// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only

// Qt-Security score:significant reason:default

#include <private/qdrawhelper_x86_p.h>

#ifdef QT_COMPILER_SUPPORTS_SSE2

#include <private/qdrawingprimitive_sse2_p.h>

#include <private/qpaintengine_raster_p.h>

QT_BEGIN_NAMESPACE

#ifndef QDRAWHELPER_AVX

// in AVX mode, we'll use the SSSE3 code

void qt_blend_argb32_on_argb32_sse2(uchar *destPixels, int dbpl,

                                    const uchar *srcPixels, int sbpl,

                                    int w, int h,

                                    int const_alpha)

{

    const quint32 *src = (const quint32 *) srcPixels;

    quint32 *dst = (quint32 *) destPixels;

    if (const_alpha == 256) {

        const __m128i alphaMask = _mm_set1_epi32(0xff000000);

        const __m128i nullVector = _mm_set1_epi32(0);

        const __m128i half = _mm_set1_epi16(0x80);

        const __m128i one = _mm_set1_epi16(0xff);

        const __m128i colorMask = _mm_set1_epi32(0x00ff00ff);

        for (int y = 0; y < h; ++y) {

            BLEND_SOURCE_OVER_ARGB32_SSE2(dst, src, w, nullVector, half, one, colorMask, alphaMask);

            dst = (quint32 *)(((uchar *) dst) + dbpl);

            src = (const quint32 *)(((const uchar *) src) + sbpl);

        }

    } else if (const_alpha != 0) {

        // dest = (s + d * sia) * ca + d * cia

        //      = s * ca + d * (sia * ca + cia)

        //      = s * ca + d * (1 - sa*ca)

        const_alpha = (const_alpha * 255) >> 8;

        const __m128i nullVector = _mm_set1_epi32(0);

        const __m128i half = _mm_set1_epi16(0x80);

        const __m128i one = _mm_set1_epi16(0xff);

        const __m128i colorMask = _mm_set1_epi32(0x00ff00ff);

        const __m128i constAlphaVector = _mm_set1_epi16(const_alpha);

        for (int y = 0; y < h; ++y) {

            BLEND_SOURCE_OVER_ARGB32_WITH_CONST_ALPHA_SSE2(dst, src, w, nullVector, half, one, colorMask, constAlphaVector)

            dst = (quint32 *)(((uchar *) dst) + dbpl);

            src = (const quint32 *)(((const uchar *) src) + sbpl);

        }

    }

}

#endif

// qblendfunctions.cpp

void qt_blend_rgb32_on_rgb32(uchar *destPixels, int dbpl,

                             const uchar *srcPixels, int sbpl,

                             int w, int h,

                             int const_alpha);

void qt_blend_rgb32_on_rgb32_sse2(uchar *destPixels, int dbpl,

                                 const uchar *srcPixels, int sbpl,

                                 int w, int h,

                                 int const_alpha)

{

    const quint32 *src = (const quint32 *) srcPixels;

    quint32 *dst = (quint32 *) destPixels;

    if (const_alpha != 256) {

        if (const_alpha != 0) {

            const __m128i half = _mm_set1_epi16(0x80);

            const __m128i colorMask = _mm_set1_epi32(0x00ff00ff);

            const_alpha = (const_alpha * 255) >> 8;

            int one_minus_const_alpha = 255 - const_alpha;

            const __m128i constAlphaVector = _mm_set1_epi16(const_alpha);

            const __m128i oneMinusConstAlpha =  _mm_set1_epi16(one_minus_const_alpha);

            for (int y = 0; y < h; ++y) {

                int x = 0;

                // First, align dest to 16 bytes:

                ALIGNMENT_PROLOGUE_16BYTES(dst, x, w) {

                    dst[x] = INTERPOLATE_PIXEL_255(src[x], const_alpha, dst[x], one_minus_const_alpha);

                }

                for (; x < w-3; x += 4) {

                    __m128i srcVector = _mm_loadu_si128((const __m128i *)&src[x]);

                    const __m128i dstVector = _mm_load_si128((__m128i *)&dst[x]);

                    __m128i result;

                    INTERPOLATE_PIXEL_255_SSE2(result, srcVector, dstVector, constAlphaVector, oneMinusConstAlpha, colorMask, half);

                    _mm_store_si128((__m128i *)&dst[x], result);

                }

                SIMD_EPILOGUE(x, w, 3)

                    dst[x] = INTERPOLATE_PIXEL_255(src[x], const_alpha, dst[x], one_minus_const_alpha);

                dst = (quint32 *)(((uchar *) dst) + dbpl);

                src = (const quint32 *)(((const uchar *) src) + sbpl);

            }

        }

    } else {

        qt_blend_rgb32_on_rgb32(destPixels, dbpl, srcPixels, sbpl, w, h, const_alpha);

    }

}

void QT_FASTCALL comp_func_SourceOver_sse2(uint *destPixels, const uint *srcPixels, int length, uint const_alpha)

{

    Q_ASSERT(const_alpha < 256);

    const quint32 *src = (const quint32 *) srcPixels;

    quint32 *dst = (quint32 *) destPixels;

    const __m128i nullVector = _mm_set1_epi32(0);

    const __m128i half = _mm_set1_epi16(0x80);

    const __m128i one = _mm_set1_epi16(0xff);

    const __m128i colorMask = _mm_set1_epi32(0x00ff00ff);

    if (const_alpha == 255) {

        const __m128i alphaMask = _mm_set1_epi32(0xff000000);

        BLEND_SOURCE_OVER_ARGB32_SSE2(dst, src, length, nullVector, half, one, colorMask, alphaMask);

    } else {

        const __m128i constAlphaVector = _mm_set1_epi16(const_alpha);

        BLEND_SOURCE_OVER_ARGB32_WITH_CONST_ALPHA_SSE2(dst, src, length, nullVector, half, one, colorMask, constAlphaVector);

    }

}

void QT_FASTCALL comp_func_Plus_sse2(uint *dst, const uint *src, int length, uint const_alpha)

{

    int x = 0;

    if (const_alpha == 255) {

        // 1) Prologue: align destination on 16 bytes

        ALIGNMENT_PROLOGUE_16BYTES(dst, x, length)

            dst[x] = comp_func_Plus_one_pixel(dst[x], src[x]);

        // 2) composition with SSE2

        for (; x < length - 3; x += 4) {

            const __m128i srcVector = _mm_loadu_si128((const __m128i *)&src[x]);

            const __m128i dstVector = _mm_load_si128((__m128i *)&dst[x]);

            const __m128i result = _mm_adds_epu8(srcVector, dstVector);

            _mm_store_si128((__m128i *)&dst[x], result);

        }

        // 3) Epilogue:

        SIMD_EPILOGUE(x, length, 3)

            dst[x] = comp_func_Plus_one_pixel(dst[x], src[x]);

    } else {

        const int one_minus_const_alpha = 255 - const_alpha;

        const __m128i constAlphaVector = _mm_set1_epi16(const_alpha);

        const __m128i oneMinusConstAlpha =  _mm_set1_epi16(one_minus_const_alpha);

        // 1) Prologue: align destination on 16 bytes

        ALIGNMENT_PROLOGUE_16BYTES(dst, x, length)

            dst[x] = comp_func_Plus_one_pixel_const_alpha(dst[x], src[x], const_alpha, one_minus_const_alpha);

        const __m128i half = _mm_set1_epi16(0x80);

        const __m128i colorMask = _mm_set1_epi32(0x00ff00ff);

        // 2) composition with SSE2

        for (; x < length - 3; x += 4) {

            const __m128i srcVector = _mm_loadu_si128((const __m128i *)&src[x]);

            const __m128i dstVector = _mm_load_si128((__m128i *)&dst[x]);

            __m128i result = _mm_adds_epu8(srcVector, dstVector);

            INTERPOLATE_PIXEL_255_SSE2(result, result, dstVector, constAlphaVector, oneMinusConstAlpha, colorMask, half)

            _mm_store_si128((__m128i *)&dst[x], result);

        }

        // 3) Epilogue:

        SIMD_EPILOGUE(x, length, 3)

            dst[x] = comp_func_Plus_one_pixel_const_alpha(dst[x], src[x], const_alpha, one_minus_const_alpha);

    }

}

void QT_FASTCALL comp_func_Source_sse2(uint *dst, const uint *src, int length, uint const_alpha)

{

    if (const_alpha == 255) {

        ::memcpy(dst, src, length * sizeof(uint));

    } else {

        const int ialpha = 255 - const_alpha;

        int x = 0;

        // 1) prologue, align on 16 bytes

        ALIGNMENT_PROLOGUE_16BYTES(dst, x, length)

            dst[x] = INTERPOLATE_PIXEL_255(src[x], const_alpha, dst[x], ialpha);

        // 2) interpolate pixels with SSE2

        const __m128i half = _mm_set1_epi16(0x80);

        const __m128i colorMask = _mm_set1_epi32(0x00ff00ff);

        const __m128i constAlphaVector = _mm_set1_epi16(const_alpha);

        const __m128i oneMinusConstAlpha =  _mm_set1_epi16(ialpha);

        for (; x < length - 3; x += 4) {

            const __m128i srcVector = _mm_loadu_si128((const __m128i *)&src[x]);

            __m128i dstVector = _mm_load_si128((__m128i *)&dst[x]);

            INTERPOLATE_PIXEL_255_SSE2(dstVector, srcVector, dstVector, constAlphaVector, oneMinusConstAlpha, colorMask, half)

            _mm_store_si128((__m128i *)&dst[x], dstVector);

        }

        // 3) Epilogue

        SIMD_EPILOGUE(x, length, 3)

            dst[x] = INTERPOLATE_PIXEL_255(src[x], const_alpha, dst[x], ialpha);

    }

}

#ifndef __haswell__

Q_NEVER_INLINE static

void Q_DECL_VECTORCALL qt_memfillXX_aligned(void *dest, __m128i value128, quintptr bytecount)

{

    __m128i *dst128 = reinterpret_cast<__m128i *>(dest);

    __m128i *end128 = reinterpret_cast<__m128i *>(static_cast<uchar *>(dest) + bytecount);

    while (dst128 + 4 <= end128) {

        _mm_store_si128(dst128 + 0, value128);

        _mm_store_si128(dst128 + 1, value128);

        _mm_store_si128(dst128 + 2, value128);

        _mm_store_si128(dst128 + 3, value128);

        dst128 += 4;

    }

    bytecount %= 4 * sizeof(__m128i);

    switch (bytecount / sizeof(__m128i)) {

    case 3: _mm_store_si128(dst128++, value128); Q_FALLTHROUGH();

    case 2: _mm_store_si128(dst128++, value128); Q_FALLTHROUGH();

    case 1: _mm_store_si128(dst128++, value128);

    }

}

void qt_memfill64_sse2(quint64 *dest, quint64 value, qsizetype count)

{

    quintptr misaligned = quintptr(dest) % sizeof(__m128i);

    if (misaligned && count) {

#if defined(Q_PROCESSOR_X86_32)

        // Before SSE came out, the alignment of the stack used to be only 4

        // bytes and some OS/ABIs (notably, code generated by MSVC) still only

        // align to that. In any case, we cannot count on the alignment of

        // quint64 to be 8 -- see QtPrivate::AlignOf_WorkaroundForI386Abi in

        // qglobal.h.

        //

        // If the pointer is not aligned to at least 8 bytes, then we'll never

        // in turn hit a multiple of 16 for the qt_memfillXX_aligned call

        // below.

        if (Q_UNLIKELY(misaligned % sizeof(quint64)))

            return qt_memfill_template(dest, value, count);

#endif

        *dest++ = value;

        --count;

    }

    if (count % 2) {

        dest[count - 1] = value;

        --count;

    }

    qt_memfillXX_aligned(dest, _mm_set1_epi64x(value), count * sizeof(quint64));

}

void qt_memfill32_sse2(quint32 *dest, quint32 value, qsizetype count)

{

    if (count < 4) {

        // this simplifies the code below: the first switch can fall through

        // without checking the value of count

        switch (count) {

        case 3: *dest++ = value; Q_FALLTHROUGH();

        case 2: *dest++ = value; Q_FALLTHROUGH();

        case 1: *dest   = value;

        }

        return;

    }

    const int align = (quintptr)(dest) & 0xf;

    switch (align) {

    case 4:  *dest++ = value; --count; Q_FALLTHROUGH();

    case 8:  *dest++ = value; --count; Q_FALLTHROUGH();

    case 12: *dest++ = value; --count;

    }

    const int rest = count & 0x3;

    if (rest) {

        switch (rest) {

        case 3: dest[count - 3] = value; Q_FALLTHROUGH();

        case 2: dest[count - 2] = value; Q_FALLTHROUGH();

        case 1: dest[count - 1] = value;

        }

    }

    qt_memfillXX_aligned(dest, _mm_set1_epi32(value), count * sizeof(quint32));

}

#endif // !__haswell__

void QT_FASTCALL comp_func_solid_Source_sse2(uint *destPixels, int length, uint color, uint const_alpha)

{

    if (const_alpha == 255) {

        qt_memfill32(destPixels, color, length);

    } else {

        const quint32 ialpha = 255 - const_alpha;

        color = BYTE_MUL(color, const_alpha);

        int x = 0;

        quint32 *dst = (quint32 *) destPixels;

        const __m128i colorVector = _mm_set1_epi32(color);

        const __m128i colorMask = _mm_set1_epi32(0x00ff00ff);

        const __m128i half = _mm_set1_epi16(0x80);

        const __m128i iAlphaVector = _mm_set1_epi16(ialpha);

        ALIGNMENT_PROLOGUE_16BYTES(dst, x, length)

            destPixels[x] = color + BYTE_MUL(destPixels[x], ialpha);

        for (; x < length-3; x += 4) {

            __m128i dstVector = _mm_load_si128((__m128i *)&dst[x]);

            BYTE_MUL_SSE2(dstVector, dstVector, iAlphaVector, colorMask, half);

            dstVector = _mm_add_epi8(colorVector, dstVector);

            _mm_store_si128((__m128i *)&dst[x], dstVector);

        }

        SIMD_EPILOGUE(x, length, 3)

            destPixels[x] = color + BYTE_MUL(destPixels[x], ialpha);

    }

}

void QT_FASTCALL comp_func_solid_SourceOver_sse2(uint *destPixels, int length, uint color, uint const_alpha)

{

    if ((const_alpha & qAlpha(color)) == 255) {

        qt_memfill32(destPixels, color, length);

    } else {

        if (const_alpha != 255)

            color = BYTE_MUL(color, const_alpha);

        const quint32 minusAlphaOfColor = qAlpha(~color);

        int x = 0;

        quint32 *dst = (quint32 *) destPixels;

        const __m128i colorVector = _mm_set1_epi32(color);

        const __m128i colorMask = _mm_set1_epi32(0x00ff00ff);

        const __m128i half = _mm_set1_epi16(0x80);

        const __m128i minusAlphaOfColorVector = _mm_set1_epi16(minusAlphaOfColor);

        ALIGNMENT_PROLOGUE_16BYTES(dst, x, length)

            destPixels[x] = color + BYTE_MUL(destPixels[x], minusAlphaOfColor);

        for (; x < length-3; x += 4) {

            __m128i dstVector = _mm_load_si128((__m128i *)&dst[x]);

            BYTE_MUL_SSE2(dstVector, dstVector, minusAlphaOfColorVector, colorMask, half);

            dstVector = _mm_add_epi8(colorVector, dstVector);

            _mm_store_si128((__m128i *)&dst[x], dstVector);

        }

        SIMD_EPILOGUE(x, length, 3)

            destPixels[x] = color + BYTE_MUL(destPixels[x], minusAlphaOfColor);

    }

}

void qt_bitmapblit32_sse2_base(QRasterBuffer *rasterBuffer, int x, int y,

                          quint32 color,

                          const uchar *src, int width, int height, int stride)

{

    quint32 *dest = reinterpret_cast<quint32*>(rasterBuffer->scanLine(y)) + x;

    const int destStride = rasterBuffer->stride<quint32>();

    const __m128i c128 = _mm_set1_epi32(color);

    const __m128i maskmask1 = _mm_set_epi32(0x10101010, 0x20202020,

                                            0x40404040, 0x80808080);

    const __m128i maskadd1 = _mm_set_epi32(0x70707070, 0x60606060,

                                           0x40404040, 0x00000000);

    if (width > 4) {

        const __m128i maskmask2 = _mm_set_epi32(0x01010101, 0x02020202,

                                                0x04040404, 0x08080808);

        const __m128i maskadd2 = _mm_set_epi32(0x7f7f7f7f, 0x7e7e7e7e,

                                               0x7c7c7c7c, 0x78787878);

        while (--height >= 0) {

            for (int x = 0; x < width; x += 8) {

                const quint8 s = src[x >> 3];

                if (!s)

                    continue;

                __m128i mask1 = _mm_set1_epi8(s);

                __m128i mask2 = mask1;

                mask1 = _mm_and_si128(mask1, maskmask1);

                mask1 = _mm_add_epi8(mask1, maskadd1);

                _mm_maskmoveu_si128(c128, mask1, (char*)(dest + x));

                mask2 = _mm_and_si128(mask2, maskmask2);

                mask2 = _mm_add_epi8(mask2, maskadd2);

                _mm_maskmoveu_si128(c128, mask2, (char*)(dest + x + 4));

            }

            dest += destStride;

            src += stride;

        }

    } else {

        while (--height >= 0) {

            const quint8 s = *src;

            if (s) {

                __m128i mask1 = _mm_set1_epi8(s);

                mask1 = _mm_and_si128(mask1, maskmask1);

                mask1 = _mm_add_epi8(mask1, maskadd1);

                _mm_maskmoveu_si128(c128, mask1, (char*)(dest));

            }

            dest += destStride;

            src += stride;

        }

    }

}

void qt_bitmapblit32_sse2(QRasterBuffer *rasterBuffer, int x, int y,

                          const QRgba64 &color,

                          const uchar *src, int width, int height, int stride)

{

    qt_bitmapblit32_sse2_base(rasterBuffer, x, y, color.toArgb32(), src, width, height, stride);

}

void qt_bitmapblit8888_sse2(QRasterBuffer *rasterBuffer, int x, int y,

                            const QRgba64 &color,

                            const uchar *src, int width, int height, int stride)

{

    qt_bitmapblit32_sse2_base(rasterBuffer, x, y, ARGB2RGBA(color.toArgb32()), src, width, height, stride);

}

void qt_bitmapblit16_sse2(QRasterBuffer *rasterBuffer, int x, int y,

                          const QRgba64 &color,

                          const uchar *src, int width, int height, int stride)

{

    const quint16 c = qConvertRgb32To16(color.toArgb32());

    quint16 *dest = reinterpret_cast<quint16*>(rasterBuffer->scanLine(y)) + x;

    const int destStride = rasterBuffer->stride<quint32>();

    const __m128i c128 = _mm_set1_epi16(c);

QT_WARNING_DISABLE_MSVC(4309) // truncation of constant value

    const __m128i maskmask = _mm_set_epi16(0x0101, 0x0202, 0x0404, 0x0808,

                                           0x1010, 0x2020, 0x4040, 0x8080);

    const __m128i maskadd = _mm_set_epi16(0x7f7f, 0x7e7e, 0x7c7c, 0x7878,

                                          0x7070, 0x6060, 0x4040, 0x0000);

    while (--height >= 0) {

        for (int x = 0; x < width; x += 8) {

            const quint8 s = src[x >> 3];

            if (!s)

                continue;

            __m128i mask = _mm_set1_epi8(s);

            mask = _mm_and_si128(mask, maskmask);

            mask = _mm_add_epi8(mask, maskadd);

            _mm_maskmoveu_si128(c128, mask, (char*)(dest + x));

        }

        dest += destStride;

        src += stride;

    }

}

class QSimdSse2

{

public:

    typedef __m128i Int32x4;

    typedef __m128 Float32x4;

    union Vect_buffer_i { Int32x4 v; int i[4]; };

    union Vect_buffer_f { Float32x4 v; float f[4]; };

    static inline Float32x4 Q_DECL_VECTORCALL v_dup(float x) { return _mm_set1_ps(x); }

    static inline Float32x4 Q_DECL_VECTORCALL v_dup(double x) { return _mm_set1_ps(x); }

    static inline Int32x4 Q_DECL_VECTORCALL v_dup(int x) { return _mm_set1_epi32(x); }

    static inline Int32x4 Q_DECL_VECTORCALL v_dup(uint x) { return _mm_set1_epi32(x); }

    static inline Float32x4 Q_DECL_VECTORCALL v_add(Float32x4 a, Float32x4 b) { return _mm_add_ps(a, b); }

    static inline Int32x4 Q_DECL_VECTORCALL v_add(Int32x4 a, Int32x4 b) { return _mm_add_epi32(a, b); }

    static inline Float32x4 Q_DECL_VECTORCALL v_max(Float32x4 a, Float32x4 b) { return _mm_max_ps(a, b); }

    static inline Float32x4 Q_DECL_VECTORCALL v_min(Float32x4 a, Float32x4 b) { return _mm_min_ps(a, b); }

    static inline Int32x4 Q_DECL_VECTORCALL v_min_16(Int32x4 a, Int32x4 b) { return _mm_min_epi16(a, b); }

    static inline Int32x4 Q_DECL_VECTORCALL v_and(Int32x4 a, Int32x4 b) { return _mm_and_si128(a, b); }

    static inline Float32x4 Q_DECL_VECTORCALL v_sub(Float32x4 a, Float32x4 b) { return _mm_sub_ps(a, b); }

    static inline Int32x4 Q_DECL_VECTORCALL v_sub(Int32x4 a, Int32x4 b) { return _mm_sub_epi32(a, b); }

    static inline Float32x4 Q_DECL_VECTORCALL v_mul(Float32x4 a, Float32x4 b) { return _mm_mul_ps(a, b); }

    static inline Float32x4 Q_DECL_VECTORCALL v_sqrt(Float32x4 x) { return _mm_sqrt_ps(x); }

    static inline Int32x4 Q_DECL_VECTORCALL v_toInt(Float32x4 x) { return _mm_cvttps_epi32(x); }

    static inline Int32x4 Q_DECL_VECTORCALL v_greaterOrEqual(Float32x4 a, Float32x4 b) { return _mm_castps_si128(_mm_cmpgt_ps(a, b)); }

};

const uint * QT_FASTCALL qt_fetch_radial_gradient_sse2(uint *buffer, const Operator *op, const QSpanData *data,

                                                       int y, int x, int length)

{

    return qt_fetch_radial_gradient_template<QRadialFetchSimd<QSimdSse2>,uint>(buffer, op, data, y, x, length);

}

void qt_scale_image_argb32_on_argb32_sse2(uchar *destPixels, int dbpl,

                                          const uchar *srcPixels, int sbpl, int srch,

                                          const QRectF &targetRect,

                                          const QRectF &sourceRect,

                                          const QRect &clip,

                                          int const_alpha)

{

    if (const_alpha != 256) {

        // from qblendfunctions.cpp

        extern void qt_scale_image_argb32_on_argb32(uchar *destPixels, int dbpl,

                                               const uchar *srcPixels, int sbpl, int srch,

                                               const QRectF &targetRect,

                                               const QRectF &sourceRect,

                                               const QRect &clip,

                                               int const_alpha);

        return qt_scale_image_argb32_on_argb32(destPixels, dbpl, srcPixels, sbpl, srch, targetRect, sourceRect, clip, const_alpha);

    }

    qreal sx = sourceRect.width() / (qreal)targetRect.width();

    qreal sy = sourceRect.height() / (qreal)targetRect.height();

    const int ix = 0x00010000 * sx;

    const int iy = 0x00010000 * sy;

    QRect tr = targetRect.normalized().toRect();

    tr = tr.intersected(clip);

    if (tr.isEmpty())

        return;

    const int tx1 = tr.left();

    const int ty1 = tr.top();

    int h = tr.height();

    int w = tr.width();

    quint32 basex;

    quint32 srcy;

    if (sx < 0) {

        int dstx = qFloor((tx1 + qreal(0.5) - targetRect.right()) * sx * 65536) + 1;

        basex = quint32(sourceRect.right() * 65536) + dstx;

    } else {

        int dstx = qCeil((tx1 + qreal(0.5) - targetRect.left()) * sx * 65536) - 1;

        basex = quint32(sourceRect.left() * 65536) + dstx;

    }

    if (sy < 0) {

        int dsty = qFloor((ty1 + qreal(0.5) - targetRect.bottom()) * sy * 65536) + 1;

        srcy = quint32(sourceRect.bottom() * 65536) + dsty;

    } else {

        int dsty = qCeil((ty1 + qreal(0.5) - targetRect.top()) * sy * 65536) - 1;

        srcy = quint32(sourceRect.top() * 65536) + dsty;

    }

    quint32 *dst = ((quint32 *) (destPixels + ty1 * dbpl)) + tx1;

    const __m128i nullVector = _mm_setzero_si128();

    const __m128i half = _mm_set1_epi16(0x80);

    const __m128i one = _mm_set1_epi16(0xff);

    const __m128i colorMask = _mm_set1_epi32(0x00ff00ff);

    const __m128i alphaMask = _mm_set1_epi32(0xff000000);

    const __m128i ixVector = _mm_set1_epi32(4*ix);

    // this bounds check here is required as floating point rounding above might in some cases lead to

    // w/h values that are one pixel too large, falling outside of the valid image area.

    const int ystart = srcy >> 16;

    if (ystart >= srch && iy < 0) {

        srcy += iy;

        --h;

    }

    const int xstart = basex >> 16;

    if (xstart >=  (int)(sbpl/sizeof(quint32)) && ix < 0) {

        basex += ix;

        --w;

    }

    int yend = (srcy + iy * (h - 1)) >> 16;

    if (yend < 0 || yend >= srch)

        --h;

    int xend = (basex + ix * (w - 1)) >> 16;

    if (xend < 0 || xend >= (int)(sbpl/sizeof(quint32)))

        --w;

    while (--h >= 0) {

        const uint *src = (const quint32 *) (srcPixels + (srcy >> 16) * sbpl);

        int srcx = basex;

        int x = 0;

        ALIGNMENT_PROLOGUE_16BYTES(dst, x, w) {

            uint s = src[srcx >> 16];

            dst[x] = s + BYTE_MUL(dst[x], qAlpha(~s));

            srcx += ix;

        }

        __m128i srcxVector = _mm_set_epi32(srcx, srcx + ix, srcx + ix + ix, srcx + ix + ix + ix);

        for (; x < (w - 3); x += 4) {

            const int idx0 = _mm_extract_epi16(srcxVector, 1);

            const int idx1 = _mm_extract_epi16(srcxVector, 3);

            const int idx2 = _mm_extract_epi16(srcxVector, 5);

            const int idx3 = _mm_extract_epi16(srcxVector, 7);

            srcxVector = _mm_add_epi32(srcxVector, ixVector);

            const __m128i srcVector = _mm_set_epi32(src[idx0], src[idx1], src[idx2], src[idx3]);

            BLEND_SOURCE_OVER_ARGB32_SSE2_helper(dst, srcVector, nullVector, half, one, colorMask, alphaMask);

        }

        SIMD_EPILOGUE(x, w, 3) {

            uint s = src[(basex + x*ix) >> 16];

            dst[x] = s + BYTE_MUL(dst[x], qAlpha(~s));

        }

        dst = (quint32 *)(((uchar *) dst) + dbpl);

        srcy += iy;

    }

}

QT_END_NAMESPACE

#endif // QT_COMPILER_SUPPORTS_SSE2