Use the C99 keyword "restrict" in compilers that support it

This allows the compiler to produce better / smaller code due to not
being required to deal with two pointers possibly aliasing each
other. This also enables vectorisation where otherwise the compiler
wouldn't be able to do.

Change-Id: Ie7db3a54a1ba22f87ac5283d5c43905707957549
Reviewed-by: Samuel Rødal <samuel.rodal@nokia.com>

2 files changed, 61 insertions, 59 deletions

diff --git a/src/gui/painting/qdrawhelper.cpp b/src/gui/painting/qdrawhelper.cpp
index 919a19eb9b..de331a3853 100644
--- a/src/gui/painting/qdrawhelper.cpp
+++ b/src/gui/painting/qdrawhelper.cpp
@@ -68,7 +68,6 @@
 
 QT_BEGIN_NAMESPACE
 
-
 #define MASK(src, a) src = BYTE_MUL(src, a)
 
 /*
@@ -316,7 +315,7 @@ FetchPixelFunc qFetchPixel[QPixelLayout::BPPCount] = {
 
 static uint * QT_FASTCALL destFetchMono(uint *buffer, QRasterBuffer *rasterBuffer, int x, int y, int length)
 {
-    uchar *data = (uchar *)rasterBuffer->scanLine(y);
+    uchar *Q_DECL_RESTRICT data = (uchar *)rasterBuffer->scanLine(y);
     uint *start = buffer;
     const uint *end = buffer + length;
     while (buffer < end) {
@@ -329,7 +328,7 @@ static uint * QT_FASTCALL destFetchMono(uint *buffer, QRasterBuffer *rasterBuffe
 
 static uint * QT_FASTCALL destFetchMonoLsb(uint *buffer, QRasterBuffer *rasterBuffer, int x, int y, int length)
 {
-    uchar *data = (uchar *)rasterBuffer->scanLine(y);
+    uchar *Q_DECL_RESTRICT data = (uchar *)rasterBuffer->scanLine(y);
     uint *start = buffer;
     const uint *end = buffer + length;
     while (buffer < end) {
@@ -347,7 +346,7 @@ static uint * QT_FASTCALL destFetchARGB32P(uint *, QRasterBuffer *rasterBuffer,
 
 static uint * QT_FASTCALL destFetchRGB16(uint *buffer, QRasterBuffer *rasterBuffer, int x, int y, int length)
 {
-    const ushort *data = (const ushort *)rasterBuffer->scanLine(y) + x;
+    const ushort *Q_DECL_RESTRICT data = (const ushort *)rasterBuffer->scanLine(y) + x;
     for (int i = 0; i < length; ++i)
         buffer[i] = qConvertRgb16To32(data[i]);
     return buffer;
@@ -418,7 +417,7 @@ static inline QRgb findNearestColor(QRgb color, QRasterBuffer *rbuf)
 
 static void QT_FASTCALL destStoreMono(QRasterBuffer *rasterBuffer, int x, int y, const uint *buffer, int length)
 {
-    uchar *data = (uchar *)rasterBuffer->scanLine(y);
+    uchar *Q_DECL_RESTRICT data = (uchar *)rasterBuffer->scanLine(y);
     if (rasterBuffer->monoDestinationWithClut) {
         for (int i = 0; i < length; ++i) {
             if (buffer[i] == rasterBuffer->destColor0) {
@@ -445,7 +444,7 @@ static void QT_FASTCALL destStoreMono(QRasterBuffer *rasterBuffer, int x, int y,
 
 static void QT_FASTCALL destStoreMonoLsb(QRasterBuffer *rasterBuffer, int x, int y, const uint *buffer, int length)
 {
-    uchar *data = (uchar *)rasterBuffer->scanLine(y);
+    uchar *Q_DECL_RESTRICT data = (uchar *)rasterBuffer->scanLine(y);
     if (rasterBuffer->monoDestinationWithClut) {
         for (int i = 0; i < length; ++i) {
             if (buffer[i] == rasterBuffer->destColor0) {
@@ -2039,7 +2038,7 @@ void QT_FASTCALL comp_func_solid_Source(uint *dest, int length, uint color, uint
     }
 }
 
-void QT_FASTCALL comp_func_Source(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_Source(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255) {
         ::memcpy(dest, src, length * sizeof(uint));
@@ -2082,7 +2081,7 @@ void QT_FASTCALL comp_func_solid_SourceOver(uint *dest, int length, uint color,
     }
 }
 
-void QT_FASTCALL comp_func_SourceOver(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_SourceOver(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     PRELOAD_INIT2(dest, src)
     if (const_alpha == 255) {
@@ -2120,7 +2119,7 @@ void QT_FASTCALL comp_func_solid_DestinationOver(uint *dest, int length, uint co
     }
 }
 
-void QT_FASTCALL comp_func_DestinationOver(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_DestinationOver(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     PRELOAD_INIT2(dest, src)
     if (const_alpha == 255) {
@@ -2162,7 +2161,7 @@ void QT_FASTCALL comp_func_solid_SourceIn(uint *dest, int length, uint color, ui
     }
 }
 
-void QT_FASTCALL comp_func_SourceIn(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_SourceIn(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     PRELOAD_INIT2(dest, src)
     if (const_alpha == 255) {
@@ -2199,7 +2198,7 @@ void QT_FASTCALL comp_func_solid_DestinationIn(uint *dest, int length, uint colo
     }
 }
 
-void QT_FASTCALL comp_func_DestinationIn(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_DestinationIn(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     PRELOAD_INIT2(dest, src)
     if (const_alpha == 255) {
@@ -2241,7 +2240,7 @@ void QT_FASTCALL comp_func_solid_SourceOut(uint *dest, int length, uint color, u
     }
 }
 
-void QT_FASTCALL comp_func_SourceOut(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_SourceOut(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     PRELOAD_INIT2(dest, src)
     if (const_alpha == 255) {
@@ -2277,7 +2276,7 @@ void QT_FASTCALL comp_func_solid_DestinationOut(uint *dest, int length, uint col
     }
 }
 
-void QT_FASTCALL comp_func_DestinationOut(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_DestinationOut(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     PRELOAD_INIT2(dest, src)
     if (const_alpha == 255) {
@@ -2314,7 +2313,7 @@ void QT_FASTCALL comp_func_solid_SourceAtop(uint *dest, int length, uint color,
     }
 }
 
-void QT_FASTCALL comp_func_SourceAtop(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_SourceAtop(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     PRELOAD_INIT2(dest, src)
     if (const_alpha == 255) {
@@ -2354,7 +2353,7 @@ void QT_FASTCALL comp_func_solid_DestinationAtop(uint *dest, int length, uint co
     }
 }
 
-void QT_FASTCALL comp_func_DestinationAtop(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_DestinationAtop(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     PRELOAD_INIT2(dest, src)
     if (const_alpha == 255) {
@@ -2396,7 +2395,7 @@ void QT_FASTCALL comp_func_solid_XOR(uint *dest, int length, uint color, uint co
     }
 }
 
-void QT_FASTCALL comp_func_XOR(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_XOR(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     PRELOAD_INIT2(dest, src)
     if (const_alpha == 255) {
@@ -2472,7 +2471,7 @@ void QT_FASTCALL comp_func_solid_Plus(uint *dest, int length, uint color, uint c
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Plus_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Plus_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -2486,7 +2485,7 @@ Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Plus_impl(uint *dest, const uin
     }
 }
 
-void QT_FASTCALL comp_func_Plus(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_Plus(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255)
         comp_func_Plus_impl(dest, src, length, QFullCoverage());
@@ -2536,7 +2535,7 @@ void QT_FASTCALL comp_func_solid_Multiply(uint *dest, int length, uint color, ui
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Multiply_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Multiply_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -2558,7 +2557,7 @@ Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Multiply_impl(uint *dest, const
     }
 }
 
-void QT_FASTCALL comp_func_Multiply(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_Multiply(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255)
         comp_func_Multiply_impl(dest, src, length, QFullCoverage());
@@ -2604,7 +2603,7 @@ void QT_FASTCALL comp_func_solid_Screen(uint *dest, int length, uint color, uint
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Screen_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Screen_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -2683,7 +2682,7 @@ void QT_FASTCALL comp_func_solid_Overlay(uint *dest, int length, uint color, uin
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Overlay_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Overlay_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -2705,7 +2704,7 @@ Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Overlay_impl(uint *dest, const
     }
 }
 
-void QT_FASTCALL comp_func_Overlay(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_Overlay(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255)
         comp_func_Overlay_impl(dest, src, length, QFullCoverage());
@@ -2756,7 +2755,7 @@ void QT_FASTCALL comp_func_solid_Darken(uint *dest, int length, uint color, uint
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Darken_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Darken_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -2778,7 +2777,7 @@ Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Darken_impl(uint *dest, const u
     }
 }
 
-void QT_FASTCALL comp_func_Darken(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_Darken(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255)
         comp_func_Darken_impl(dest, src, length, QFullCoverage());
@@ -2829,7 +2828,7 @@ void QT_FASTCALL comp_func_solid_Lighten(uint *dest, int length, uint color, uin
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Lighten_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Lighten_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -2851,7 +2850,7 @@ Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Lighten_impl(uint *dest, const
     }
 }
 
-void QT_FASTCALL comp_func_Lighten(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_Lighten(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255)
         comp_func_Lighten_impl(dest, src, length, QFullCoverage());
@@ -2912,7 +2911,7 @@ void QT_FASTCALL comp_func_solid_ColorDodge(uint *dest, int length, uint color,
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_ColorDodge_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_ColorDodge_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -2934,7 +2933,7 @@ Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_ColorDodge_impl(uint *dest, con
     }
 }
 
-void QT_FASTCALL comp_func_ColorDodge(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_ColorDodge(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255)
         comp_func_ColorDodge_impl(dest, src, length, QFullCoverage());
@@ -2995,7 +2994,7 @@ void QT_FASTCALL comp_func_solid_ColorBurn(uint *dest, int length, uint color, u
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_ColorBurn_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_ColorBurn_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -3017,7 +3016,7 @@ Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_ColorBurn_impl(uint *dest, cons
     }
 }
 
-void QT_FASTCALL comp_func_ColorBurn(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_ColorBurn(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255)
         comp_func_ColorBurn_impl(dest, src, length, QFullCoverage());
@@ -3075,7 +3074,7 @@ void QT_FASTCALL comp_func_solid_HardLight(uint *dest, int length, uint color, u
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_HardLight_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_HardLight_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -3097,7 +3096,7 @@ Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_HardLight_impl(uint *dest, cons
     }
 }
 
-void QT_FASTCALL comp_func_HardLight(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_HardLight(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255)
         comp_func_HardLight_impl(dest, src, length, QFullCoverage());
@@ -3166,7 +3165,7 @@ void QT_FASTCALL comp_func_solid_SoftLight(uint *dest, int length, uint color, u
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_SoftLight_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_SoftLight_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -3188,7 +3187,7 @@ Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_SoftLight_impl(uint *dest, cons
     }
 }
 
-void QT_FASTCALL comp_func_SoftLight(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_SoftLight(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255)
         comp_func_SoftLight_impl(dest, src, length, QFullCoverage());
@@ -3239,7 +3238,7 @@ void QT_FASTCALL comp_func_solid_Difference(uint *dest, int length, uint color,
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Difference_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Difference_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -3261,7 +3260,7 @@ Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Difference_impl(uint *dest, con
     }
 }
 
-void QT_FASTCALL comp_func_Difference(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_Difference(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255)
         comp_func_Difference_impl(dest, src, length, QFullCoverage());
@@ -3306,7 +3305,7 @@ void QT_FASTCALL comp_func_solid_Exclusion(uint *dest, int length, uint color, u
 }
 
 template <typename T>
-Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Exclusion_impl(uint *dest, const uint *src, int length, const T &coverage)
+Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Exclusion_impl(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, const T &coverage)
 {
     PRELOAD_INIT2(dest, src)
     for (int i = 0; i < length; ++i) {
@@ -3328,7 +3327,7 @@ Q_STATIC_TEMPLATE_FUNCTION inline void comp_func_Exclusion_impl(uint *dest, cons
     }
 }
 
-void QT_FASTCALL comp_func_Exclusion(uint *dest, const uint *src, int length, uint const_alpha)
+void QT_FASTCALL comp_func_Exclusion(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha)
 {
     if (const_alpha == 255)
         comp_func_Exclusion_impl(dest, src, length, QFullCoverage());
@@ -3351,8 +3350,8 @@ void QT_FASTCALL rasterop_solid_SourceOrDestination(uint *dest,
         *dest++ |= color;
 }
 
-void QT_FASTCALL rasterop_SourceOrDestination(uint *dest,
-                                              const uint *src,
+void QT_FASTCALL rasterop_SourceOrDestination(uint *Q_DECL_RESTRICT dest,
+                                              const uint *Q_DECL_RESTRICT src,
                                               int length,
                                               uint const_alpha)
 {
@@ -3372,8 +3371,8 @@ void QT_FASTCALL rasterop_solid_SourceAndDestination(uint *dest,
         *dest++ &= color;
 }
 
-void QT_FASTCALL rasterop_SourceAndDestination(uint *dest,
-                                               const uint *src,
+void QT_FASTCALL rasterop_SourceAndDestination(uint *Q_DECL_RESTRICT dest,
+                                               const uint *Q_DECL_RESTRICT src,
                                                int length,
                                                uint const_alpha)
 {
@@ -3395,8 +3394,8 @@ void QT_FASTCALL rasterop_solid_SourceXorDestination(uint *dest,
         *dest++ ^= color;
 }
 
-void QT_FASTCALL rasterop_SourceXorDestination(uint *dest,
-                                               const uint *src,
+void QT_FASTCALL rasterop_SourceXorDestination(uint *Q_DECL_RESTRICT dest,
+                                               const uint *Q_DECL_RESTRICT src,
                                                int length,
                                                uint const_alpha)
 {
@@ -3420,8 +3419,8 @@ void QT_FASTCALL rasterop_solid_NotSourceAndNotDestination(uint *dest,
     }
 }
 
-void QT_FASTCALL rasterop_NotSourceAndNotDestination(uint *dest,
-                                                     const uint *src,
+void QT_FASTCALL rasterop_NotSourceAndNotDestination(uint *Q_DECL_RESTRICT dest,
+                                                     const uint *Q_DECL_RESTRICT src,
                                                      int length,
                                                      uint const_alpha)
 {
@@ -3445,8 +3444,8 @@ void QT_FASTCALL rasterop_solid_NotSourceOrNotDestination(uint *dest,
     }
 }
 
-void QT_FASTCALL rasterop_NotSourceOrNotDestination(uint *dest,
-                                                    const uint *src,
+void QT_FASTCALL rasterop_NotSourceOrNotDestination(uint *Q_DECL_RESTRICT dest,
+                                                    const uint *Q_DECL_RESTRICT src,
                                                     int length,
                                                     uint const_alpha)
 {
@@ -3470,8 +3469,8 @@ void QT_FASTCALL rasterop_solid_NotSourceXorDestination(uint *dest,
     }
 }
 
-void QT_FASTCALL rasterop_NotSourceXorDestination(uint *dest,
-                                                  const uint *src,
+void QT_FASTCALL rasterop_NotSourceXorDestination(uint *Q_DECL_RESTRICT dest,
+                                                  const uint *Q_DECL_RESTRICT src,
                                                   int length,
                                                   uint const_alpha)
 {
@@ -3489,7 +3488,7 @@ void QT_FASTCALL rasterop_solid_NotSource(uint *dest, int length,
     qt_memfill(dest, ~color | 0xff000000, length);
 }
 
-void QT_FASTCALL rasterop_NotSource(uint *dest, const uint *src,
+void QT_FASTCALL rasterop_NotSource(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src,
                                     int length, uint const_alpha)
 {
     Q_UNUSED(const_alpha);
@@ -3510,8 +3509,8 @@ void QT_FASTCALL rasterop_solid_NotSourceAndDestination(uint *dest,
     }
 }
 
-void QT_FASTCALL rasterop_NotSourceAndDestination(uint *dest,
-                                                  const uint *src,
+void QT_FASTCALL rasterop_NotSourceAndDestination(uint *Q_DECL_RESTRICT dest,
+                                                  const uint *Q_DECL_RESTRICT src,
                                                   int length,
                                                   uint const_alpha)
 {
@@ -3534,8 +3533,8 @@ void QT_FASTCALL rasterop_solid_SourceAndNotDestination(uint *dest,
     }
 }
 
-void QT_FASTCALL rasterop_SourceAndNotDestination(uint *dest,
-                                                  const uint *src,
+void QT_FASTCALL rasterop_SourceAndNotDestination(uint *Q_DECL_RESTRICT dest,
+                                                  const uint *Q_DECL_RESTRICT src,
                                                   int length,
                                                   uint const_alpha)
 {
@@ -4049,8 +4048,8 @@ static inline quint32 interpolate_pixel_rgb16x2_255(quint32 x, quint8 a,
     return t;
 }
 
-static inline void blend_sourceOver_rgb16_rgb16(quint16 *dest,
-                                                const quint16 *src,
+static inline void blend_sourceOver_rgb16_rgb16(quint16 *Q_DECL_RESTRICT dest,
+                                                const quint16 *Q_DECL_RESTRICT src,
                                                 int length,
                                                 const quint8 alpha,
                                                 const quint8 ialpha)
diff --git a/src/gui/painting/qdrawhelper_p.h b/src/gui/painting/qdrawhelper_p.h
index 8d67e69caa..f502533443 100644
--- a/src/gui/painting/qdrawhelper_p.h
+++ b/src/gui/painting/qdrawhelper_p.h
@@ -71,12 +71,15 @@ QT_BEGIN_NAMESPACE
 // RVCT doesn't like static template functions
 #  define Q_STATIC_TEMPLATE_FUNCTION
 #  define Q_STATIC_INLINE_FUNCTION static __forceinline
+#  define Q_DECL_RESTRICT
 #elif defined(Q_CC_GNU)
 #  define Q_STATIC_TEMPLATE_FUNCTION static __attribute__((always_inline))
 #  define Q_STATIC_INLINE_FUNCTION static inline __attribute__((always_inline))
+#  define Q_DECL_RESTRICT __restrict__
 #else
 #  define Q_STATIC_TEMPLATE_FUNCTION static
 #  define Q_STATIC_INLINE_FUNCTION static inline
+#  define Q_DECL_RESTRICT
 #endif
 
 static const uint AMASK = 0xff000000;
@@ -165,7 +168,7 @@ extern DrawHelper qDrawHelper[QImage::NImageFormats];
 
 void qBlendTexture(int count, const QSpan *spans, void *userData);
 
-typedef void (QT_FASTCALL *CompositionFunction)(uint *dest, const uint *src, int length, uint const_alpha);
+typedef void (QT_FASTCALL *CompositionFunction)(uint *Q_DECL_RESTRICT dest, const uint *Q_DECL_RESTRICT src, int length, uint const_alpha);
 typedef void (QT_FASTCALL *CompositionFunctionSolid)(uint *dest, int length, uint color, uint const_alpha);
 
 struct LinearGradientValues