Remove runtime detection of Neon on ARM CPUs

Now the only way to enable Neon support is to change the mkspec.

[ChangeLog][Important Behavior Changes] Qt no longer checks for
support for the Neon FPU on ARM platforms at runtime. Code optimized
for Neon must be enabled unconditionally at compile time by ensuring
the compiler supports Neon. You may need to edit your mkspec for that.

Task-number: QTBUG-30440
Change-Id: I4df9b2bf3cd022f8ed70f02f16878cb2cb3fe6fb
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

6 files changed, 41 insertions, 44 deletions

diff --git a/src/gui/image/image.pri b/src/gui/image/image.pri
index ad860ef2db..0745cc0302 100644
--- a/src/gui/image/image.pri
+++ b/src/gui/image/image.pri
@@ -78,7 +78,9 @@ contains(QT_CONFIG, jpeg):include($$PWD/qjpeghandler.pri)
 contains(QT_CONFIG, gif):include($$PWD/qgifhandler.pri)
 
 # SIMD
-NEON_SOURCES += image/qimage_neon.cpp
+contains(QT_CPU_FEATURES.$$QT_ARCH, neon) {
+    SOURCES += image/qimage_neon.cpp
+}
 contains(QT_CPU_FEATURES.$$QT_ARCH, sse2) {
     SOURCES += image/qimage_sse2.cpp
     SSSE3_SOURCES += image/qimage_ssse3.cpp
diff --git a/src/gui/image/qimage_conversions.cpp b/src/gui/image/qimage_conversions.cpp
index 317ba45dac..193ef59fcd 100644
--- a/src/gui/image/qimage_conversions.cpp
+++ b/src/gui/image/qimage_conversions.cpp
@@ -2132,14 +2132,11 @@ void qInitImageConversions()
     }
 #endif
 
-#ifdef QT_COMPILER_SUPPORTS_NEON
-    if (qCpuHasFeature(NEON)) {
-        extern void convert_RGB888_to_RGB32_neon(QImageData *dest, const QImageData *src, Qt::ImageConversionFlags);
-        qimage_converter_map[QImage::Format_RGB888][QImage::Format_RGB32] = convert_RGB888_to_RGB32_neon;
-        qimage_converter_map[QImage::Format_RGB888][QImage::Format_ARGB32] = convert_RGB888_to_RGB32_neon;
-        qimage_converter_map[QImage::Format_RGB888][QImage::Format_ARGB32_Premultiplied] = convert_RGB888_to_RGB32_neon;
-        return;
-    }
+#ifdef __ARM_NEON__
+    extern void convert_RGB888_to_RGB32_neon(QImageData *dest, const QImageData *src, Qt::ImageConversionFlags);
+    qimage_converter_map[QImage::Format_RGB888][QImage::Format_RGB32] = convert_RGB888_to_RGB32_neon;
+    qimage_converter_map[QImage::Format_RGB888][QImage::Format_ARGB32] = convert_RGB888_to_RGB32_neon;
+    qimage_converter_map[QImage::Format_RGB888][QImage::Format_ARGB32_Premultiplied] = convert_RGB888_to_RGB32_neon;
 #endif
 }
 
diff --git a/src/gui/image/qjpeghandler.cpp b/src/gui/image/qjpeghandler.cpp
index 3ca31030c5..5187f0e9b3 100644
--- a/src/gui/image/qjpeghandler.cpp
+++ b/src/gui/image/qjpeghandler.cpp
@@ -861,7 +861,7 @@ Q_GUI_EXPORT void QT_FASTCALL qt_convert_rgb888_to_rgb32_avx(quint32 *dst, const
 QJpegHandler::QJpegHandler()
     : d(new QJpegHandlerPrivate(this))
 {
-#if defined(QT_COMPILER_SUPPORTS_NEON)
+#if defined(__ARM_NEON__)
     // from qimage_neon.cpp
 
     if (qCpuHasFeature(NEON))
diff --git a/src/gui/image/qpixmap_raster.cpp b/src/gui/image/qpixmap_raster.cpp
index be63430a78..37259adcd2 100644
--- a/src/gui/image/qpixmap_raster.cpp
+++ b/src/gui/image/qpixmap_raster.cpp
@@ -187,7 +187,7 @@ void QRasterPlatformPixmap::fill(const QColor &color)
         if (alpha != 255) {
             if (!image.hasAlphaChannel()) {
                 QImage::Format toFormat;
-#if !(defined(QT_COMPILER_SUPPORTS_NEON) || defined(__SSE2__))
+#if !(defined(__ARM_NEON__) || defined(__SSE2__))
                 if (image.format() == QImage::Format_RGB16)
                     toFormat = QImage::Format_ARGB8565_Premultiplied;
                 else if (image.format() == QImage::Format_RGB666)
@@ -316,7 +316,7 @@ void QRasterPlatformPixmap::createPixmapForImage(QImage &sourceImage, Qt::ImageC
             QImage::Format opaqueFormat = QNativeImage::systemFormat();
             QImage::Format alphaFormat = QImage::Format_ARGB32_Premultiplied;
 
-#if !defined(QT_COMPILER_SUPPORTS_NEON) && !defined(__SSE2__)
+#if !defined(__ARM_NEON__) && !defined(__SSE2__)
             switch (opaqueFormat) {
             case QImage::Format_RGB16:
                 alphaFormat = QImage::Format_ARGB8565_Premultiplied;
diff --git a/src/gui/painting/painting.pri b/src/gui/painting/painting.pri
index 271848ae73..6bf80eddbd 100644
--- a/src/gui/painting/painting.pri
+++ b/src/gui/painting/painting.pri
@@ -93,9 +93,9 @@ contains(QT_CPU_FEATURES.$$QT_ARCH, sse2) {
 }
 IWMMXT_SOURCES += painting/qdrawhelper_iwmmxt.cpp
 
-!ios {
-    NEON_SOURCES += painting/qdrawhelper_neon.cpp
-    NEON_HEADERS += painting/qdrawhelper_neon_p.h
+!ios:contains(QT_CPU_FEATURES.$$QT_ARCH, neon) {
+    SOURCES += painting/qdrawhelper_neon.cpp
+    HEADERS += painting/qdrawhelper_neon_p.h
     NEON_ASM += ../3rdparty/pixman/pixman-arm-neon-asm.S painting/qdrawhelper_neon_asm.S
 }
 
diff --git a/src/gui/painting/qdrawhelper.cpp b/src/gui/painting/qdrawhelper.cpp
index ae6a5e01e5..94ac62574b 100644
--- a/src/gui/painting/qdrawhelper.cpp
+++ b/src/gui/painting/qdrawhelper.cpp
@@ -6273,45 +6273,43 @@ void qInitDrawhelperAsm()
     }
 #endif // IWMMXT
 
-#if defined(QT_COMPILER_SUPPORTS_NEON) && !defined(Q_OS_IOS)
-    if (features & NEON) {
-        qBlendFunctions[QImage::Format_RGB32][QImage::Format_RGB32] = qt_blend_rgb32_on_rgb32_neon;
-        qBlendFunctions[QImage::Format_ARGB32_Premultiplied][QImage::Format_RGB32] = qt_blend_rgb32_on_rgb32_neon;
-        qBlendFunctions[QImage::Format_RGB32][QImage::Format_ARGB32_Premultiplied] = qt_blend_argb32_on_argb32_neon;
-        qBlendFunctions[QImage::Format_ARGB32_Premultiplied][QImage::Format_ARGB32_Premultiplied] = qt_blend_argb32_on_argb32_neon;
-        qBlendFunctions[QImage::Format_RGB16][QImage::Format_ARGB32_Premultiplied] = qt_blend_argb32_on_rgb16_neon;
-        qBlendFunctions[QImage::Format_ARGB32_Premultiplied][QImage::Format_RGB16] = qt_blend_rgb16_on_argb32_neon;
-        qBlendFunctions[QImage::Format_RGB16][QImage::Format_RGB16] = qt_blend_rgb16_on_rgb16_neon;
+#if defined(__ARM_NEON__) && !defined(Q_OS_IOS)
+    qBlendFunctions[QImage::Format_RGB32][QImage::Format_RGB32] = qt_blend_rgb32_on_rgb32_neon;
+    qBlendFunctions[QImage::Format_ARGB32_Premultiplied][QImage::Format_RGB32] = qt_blend_rgb32_on_rgb32_neon;
+    qBlendFunctions[QImage::Format_RGB32][QImage::Format_ARGB32_Premultiplied] = qt_blend_argb32_on_argb32_neon;
+    qBlendFunctions[QImage::Format_ARGB32_Premultiplied][QImage::Format_ARGB32_Premultiplied] = qt_blend_argb32_on_argb32_neon;
+    qBlendFunctions[QImage::Format_RGB16][QImage::Format_ARGB32_Premultiplied] = qt_blend_argb32_on_rgb16_neon;
+    qBlendFunctions[QImage::Format_ARGB32_Premultiplied][QImage::Format_RGB16] = qt_blend_rgb16_on_argb32_neon;
+    qBlendFunctions[QImage::Format_RGB16][QImage::Format_RGB16] = qt_blend_rgb16_on_rgb16_neon;
 #if Q_BYTE_ORDER == Q_LITTLE_ENDIAN
-        qBlendFunctions[QImage::Format_RGBX8888][QImage::Format_RGBX8888] = qt_blend_rgb32_on_rgb32_neon;
-        qBlendFunctions[QImage::Format_RGBA8888_Premultiplied][QImage::Format_RGBX8888] = qt_blend_rgb32_on_rgb32_neon;
-        qBlendFunctions[QImage::Format_RGBX8888][QImage::Format_RGBA8888_Premultiplied] = qt_blend_argb32_on_argb32_neon;
-        qBlendFunctions[QImage::Format_RGBA8888_Premultiplied][QImage::Format_RGBA8888_Premultiplied] = qt_blend_argb32_on_argb32_neon;
+    qBlendFunctions[QImage::Format_RGBX8888][QImage::Format_RGBX8888] = qt_blend_rgb32_on_rgb32_neon;
+    qBlendFunctions[QImage::Format_RGBA8888_Premultiplied][QImage::Format_RGBX8888] = qt_blend_rgb32_on_rgb32_neon;
+    qBlendFunctions[QImage::Format_RGBX8888][QImage::Format_RGBA8888_Premultiplied] = qt_blend_argb32_on_argb32_neon;
+    qBlendFunctions[QImage::Format_RGBA8888_Premultiplied][QImage::Format_RGBA8888_Premultiplied] = qt_blend_argb32_on_argb32_neon;
 #endif
 
-        qScaleFunctions[QImage::Format_RGB16][QImage::Format_ARGB32_Premultiplied] = qt_scale_image_argb32_on_rgb16_neon;
-        qScaleFunctions[QImage::Format_RGB16][QImage::Format_RGB16] = qt_scale_image_rgb16_on_rgb16_neon;
+    qScaleFunctions[QImage::Format_RGB16][QImage::Format_ARGB32_Premultiplied] = qt_scale_image_argb32_on_rgb16_neon;
+    qScaleFunctions[QImage::Format_RGB16][QImage::Format_RGB16] = qt_scale_image_rgb16_on_rgb16_neon;
 
-        qTransformFunctions[QImage::Format_RGB16][QImage::Format_ARGB32_Premultiplied] = qt_transform_image_argb32_on_rgb16_neon;
-        qTransformFunctions[QImage::Format_RGB16][QImage::Format_RGB16] = qt_transform_image_rgb16_on_rgb16_neon;
+    qTransformFunctions[QImage::Format_RGB16][QImage::Format_ARGB32_Premultiplied] = qt_transform_image_argb32_on_rgb16_neon;
+    qTransformFunctions[QImage::Format_RGB16][QImage::Format_RGB16] = qt_transform_image_rgb16_on_rgb16_neon;
 
-        qDrawHelper[QImage::Format_RGB16].alphamapBlit = qt_alphamapblit_quint16_neon;
+    qDrawHelper[QImage::Format_RGB16].alphamapBlit = qt_alphamapblit_quint16_neon;
 
-        functionForMode_C[QPainter::CompositionMode_SourceOver] = qt_blend_argb32_on_argb32_scanline_neon;
-        functionForModeSolid_C[QPainter::CompositionMode_SourceOver] = comp_func_solid_SourceOver_neon;
-        functionForMode_C[QPainter::CompositionMode_Plus] = comp_func_Plus_neon;
-        destFetchProc[QImage::Format_RGB16] = qt_destFetchRGB16_neon;
-        destStoreProc[QImage::Format_RGB16] = qt_destStoreRGB16_neon;
+    functionForMode_C[QPainter::CompositionMode_SourceOver] = qt_blend_argb32_on_argb32_scanline_neon;
+    functionForModeSolid_C[QPainter::CompositionMode_SourceOver] = comp_func_solid_SourceOver_neon;
+    functionForMode_C[QPainter::CompositionMode_Plus] = comp_func_Plus_neon;
+    destFetchProc[QImage::Format_RGB16] = qt_destFetchRGB16_neon;
+    destStoreProc[QImage::Format_RGB16] = qt_destStoreRGB16_neon;
 
-        qMemRotateFunctions[QImage::Format_RGB16][0] = qt_memrotate90_16_neon;
-        qMemRotateFunctions[QImage::Format_RGB16][2] = qt_memrotate270_16_neon;
+    qMemRotateFunctions[QImage::Format_RGB16][0] = qt_memrotate90_16_neon;
+    qMemRotateFunctions[QImage::Format_RGB16][2] = qt_memrotate270_16_neon;
         qt_memfill32 = qt_memfill32_neon;
 
-        extern const uint * QT_FASTCALL qt_fetch_radial_gradient_neon(uint *buffer, const Operator *op, const QSpanData *data,
-                                                                      int y, int x, int length);
+    extern const uint * QT_FASTCALL qt_fetch_radial_gradient_neon(uint *buffer, const Operator *op, const QSpanData *data,
+                                                                  int y, int x, int length);
 
-        qt_fetch_radial_gradient = qt_fetch_radial_gradient_neon;
-    }
+    qt_fetch_radial_gradient = qt_fetch_radial_gradient_neon;
 #endif
 
 #if defined(QT_COMPILER_SUPPORTS_MIPS_DSP)