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Branched from the monolithic repo, Qt master branch, at commit
896db169ea224deb96c59ce8af800d019de63f12

1 files changed, 149 insertions, 0 deletions

diff --git a/src/gui/image/qimage_ssse3.cpp b/src/gui/image/qimage_ssse3.cpp
new file mode 100644
index 0000000000..81e817eb73
--- /dev/null
+++ b/src/gui/image/qimage_ssse3.cpp
@@ -0,0 +1,149 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <qimage.h>
+#include <private/qimage_p.h>
+#include <private/qsimd_p.h>
+
+#ifdef QT_HAVE_SSSE3
+
+QT_BEGIN_NAMESPACE
+
+// Convert a scanline of RGB888 (src) to RGB32 (dst)
+// src must be at least len * 3 bytes
+// dst must be at least len * 4 bytes
+Q_GUI_EXPORT void QT_FASTCALL qt_convert_rgb888_to_rgb32_ssse3(quint32 *dst, const uchar *src, int len)
+{
+    quint32 *const end = dst + len;
+
+    // Prologue, align dst to 16 bytes. The alignment is done on dst because it has 4 store()
+    // for each 3 load() of src.
+    const int offsetToAlignOn16Bytes = (4 - ((reinterpret_cast<quintptr>(dst) >> 2) & 0x3)) & 0x3;
+    const int prologLength = qMin(len, offsetToAlignOn16Bytes);
+
+    for (int i = 0; i < prologLength; ++i) {
+        *dst++ = qRgb(src[0], src[1], src[2]);
+        src += 3;
+    }
+
+    // Mask the 4 first colors of the RGB888 vector
+    const __m128i shuffleMask = _mm_set_epi8(0xff, 9, 10, 11, 0xff, 6, 7, 8, 0xff, 3, 4, 5, 0xff, 0, 1, 2);
+
+    // Mask the 4 last colors of a RGB888 vector with an offset of 1 (so the last 3 bytes are RGB)
+    const __m128i shuffleMaskEnd = _mm_set_epi8(0xff, 13, 14, 15, 0xff, 10, 11, 12, 0xff, 7, 8, 9, 0xff, 4, 5, 6);
+
+    // Mask to have alpha = 0xff
+    const __m128i alphaMask = _mm_set1_epi32(0xff000000);
+
+    __m128i *inVectorPtr = (__m128i *)src;
+    __m128i *dstVectorPtr = (__m128i *)dst;
+
+    const int simdRoundCount = (len - prologLength) / 16; // one iteration in the loop converts 16 pixels
+    for (int i = 0; i < simdRoundCount; ++i) {
+        /*
+         RGB888 has 5 pixels per vector, + 1 byte from the next pixel. The idea here is
+         to load vectors of RGB888 and use palignr to select a vector out of two vectors.
+
+         After 3 loads of RGB888 and 3 stores of RGB32, we have 4 pixels left in the last
+         vector of RGB888, we can mask it directly to get a last store or RGB32. After that,
+         the first next byte is a R, and we can loop for the next 16 pixels.
+
+         The conversion itself is done with a byte permutation (pshufb).
+         */
+        __m128i firstSrcVector = _mm_lddqu_si128(inVectorPtr);
+        __m128i outputVector = _mm_shuffle_epi8(firstSrcVector, shuffleMask);
+        _mm_store_si128(dstVectorPtr, _mm_or_si128(outputVector, alphaMask));
+        ++inVectorPtr;
+        ++dstVectorPtr;
+
+        // There are 4 unused bytes left in srcVector, we need to load the next 16 bytes
+        // and load the next input with palignr
+        __m128i secondSrcVector = _mm_lddqu_si128(inVectorPtr);
+        __m128i srcVector = _mm_alignr_epi8(secondSrcVector, firstSrcVector, 12);
+        outputVector = _mm_shuffle_epi8(srcVector, shuffleMask);
+        _mm_store_si128(dstVectorPtr, _mm_or_si128(outputVector, alphaMask));
+        ++inVectorPtr;
+        ++dstVectorPtr;
+        firstSrcVector = secondSrcVector;
+
+        // We now have 8 unused bytes left in firstSrcVector
+        secondSrcVector = _mm_lddqu_si128(inVectorPtr);
+        srcVector = _mm_alignr_epi8(secondSrcVector, firstSrcVector, 8);
+        outputVector = _mm_shuffle_epi8(srcVector, shuffleMask);
+        _mm_store_si128(dstVectorPtr, _mm_or_si128(outputVector, alphaMask));
+        ++inVectorPtr;
+        ++dstVectorPtr;
+
+        // There are now 12 unused bytes in firstSrcVector.
+        // We can mask them directly, almost there.
+        outputVector = _mm_shuffle_epi8(secondSrcVector, shuffleMaskEnd);
+        _mm_store_si128(dstVectorPtr, _mm_or_si128(outputVector, alphaMask));
+        ++dstVectorPtr;
+    }
+    src = (uchar *)inVectorPtr;
+    dst = (quint32 *)dstVectorPtr;
+
+    while (dst != end) {
+        *dst++ = qRgb(src[0], src[1], src[2]);
+        src += 3;
+    }
+}
+
+void convert_RGB888_to_RGB32_ssse3(QImageData *dest, const QImageData *src, Qt::ImageConversionFlags)
+{
+    Q_ASSERT(src->format == QImage::Format_RGB888);
+    Q_ASSERT(dest->format == QImage::Format_RGB32 || dest->format == QImage::Format_ARGB32 || dest->format == QImage::Format_ARGB32_Premultiplied);
+    Q_ASSERT(src->width == dest->width);
+    Q_ASSERT(src->height == dest->height);
+
+    const uchar *src_data = (uchar *) src->data;
+    quint32 *dest_data = (quint32 *) dest->data;
+
+    for (int i = 0; i < src->height; ++i) {
+        qt_convert_rgb888_to_rgb32_ssse3(dest_data, src_data, src->width);
+        src_data += src->bytes_per_line;
+        dest_data = (quint32 *)((uchar*)dest_data + dest->bytes_per_line);
+    }
+}
+
+QT_END_NAMESPACE
+
+#endif // QT_HAVE_SSSE3