Do the conversion from RGB888 to RGB32 using Neon

Doing the conversion with Neon is 700% faster.

Help by Thiago Macieira on vacation.

Reviewed-by: Thiago Macieira

3 files changed, 123 insertions, 0 deletions

diff --git a/src/gui/image/image.pri b/src/gui/image/image.pri
index b20a04f..f89706c 100644
--- a/src/gui/image/image.pri
+++ b/src/gui/image/image.pri
@@ -94,5 +94,6 @@ contains(QT_CONFIG, tiff):include($$PWD/qtiffhandler.pri)
 contains(QT_CONFIG, gif):include($$PWD/qgifhandler.pri)
 
 # SIMD
+NEON_SOURCES += image/qimage_neon.cpp
 SSE2_SOURCES += image/qimage_sse2.cpp
 SSSE3_SOURCES += image/qimage_ssse3.cpp
diff --git a/src/gui/image/qimage.cpp b/src/gui/image/qimage.cpp
index cb834c0..ac148ee 100644
--- a/src/gui/image/qimage.cpp
+++ b/src/gui/image/qimage.cpp
@@ -3769,6 +3769,14 @@ void qInitImageConversions()
         converter_map[QImage::Format_RGB888][QImage::Format_ARGB32_Premultiplied] = convert_RGB888_to_RGB32_ssse3;
     }
 #endif
+#ifdef QT_HAVE_NEON
+    if (features & NEON) {
+        extern void convert_RGB888_to_RGB32_neon(QImageData *dest, const QImageData *src, Qt::ImageConversionFlags);
+        converter_map[QImage::Format_RGB888][QImage::Format_RGB32] = convert_RGB888_to_RGB32_neon;
+        converter_map[QImage::Format_RGB888][QImage::Format_ARGB32] = convert_RGB888_to_RGB32_neon;
+        converter_map[QImage::Format_RGB888][QImage::Format_ARGB32_Premultiplied] = convert_RGB888_to_RGB32_neon;
+    }
+#endif
 }
 
 /*!
diff --git a/src/gui/image/qimage_neon.cpp b/src/gui/image/qimage_neon.cpp
new file mode 100644
index 0000000..15bf472
--- /dev/null
+++ b/src/gui/image/qimage_neon.cpp
@@ -0,0 +1,114 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 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_NEON
+
+QT_BEGIN_NAMESPACE
+
+Q_GUI_EXPORT void QT_FASTCALL qt_convert_rgb888_to_rgb32_neon(quint32 *dst, const uchar *src, int len)
+{
+    if (!len)
+        return;
+
+    const quint32 *const end = dst + len;
+
+    // align dst on 64 bits
+    const int offsetToAlignOn8Bytes = (reinterpret_cast<quintptr>(dst) >> 2) & 0x1;
+    for (int i = 0; i < offsetToAlignOn8Bytes; ++i) {
+        *dst++ = qRgb(src[0], src[1], src[2]);
+        src += 3;
+    }
+
+    if ((len - offsetToAlignOn8Bytes) >= 8) {
+        const quint32 *const simdEnd = end - 7;
+        register uint8x8_t fullVector asm ("d3") = vdup_n_u8(0xff);
+        do {
+#if Q_BYTE_ORDER == Q_BIG_ENDIAN
+            asm volatile (
+                "vld3.8     { d4, d5, d6 }, [%[SRC]] !\n\t"
+                "vst4.8     { d3, d4, d5, d6 }, [%[DST],:64] !\n\t"
+                : [DST]"+r" (dst), [SRC]"+r" (src)
+                : "w"(fullVector)
+                : "memory", "d4", "d5", "d6"
+            );
+#else
+            asm volatile (
+                "vld3.8     { d0, d1, d2 }, [%[SRC]] !\n\t"
+                "vswp d0, d2\n\t"
+                "vst4.8     { d0, d1, d2, d3 }, [%[DST],:64] !\n\t"
+                : [DST]"+r" (dst), [SRC]"+r" (src)
+                : "w"(fullVector)
+                : "memory", "d0", "d1", "d2"
+            );
+#endif
+        } while (dst < simdEnd);
+    }
+
+    while (dst != end) {
+        *dst++ = qRgb(src[0], src[1], src[2]);
+        src += 3;
+    }
+}
+
+void convert_RGB888_to_RGB32_neon(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_neon(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_NEON