Allocate 16-byte aligned memory independent of platform for raster pool.

Fixes crash on MIPS (see original merge request
https://qt.gitorious.org/qt/qt/merge_requests/1366).

Reviewed-by: Olivier Goffart

1 files changed, 17 insertions, 37 deletions

diff --git a/src/gui/painting/qpaintengine_raster.cpp b/src/gui/painting/qpaintengine_raster.cpp
index 36786c4..bcc5f9d 100644
--- a/src/gui/painting/qpaintengine_raster.cpp
+++ b/src/gui/painting/qpaintengine_raster.cpp
@@ -3764,6 +3764,11 @@ extern "C" {
     int q_gray_rendered_spans(QT_FT_Raster raster);
 }
 
+static inline uchar *alignAddress(uchar *address, quintptr alignmentMask)
+{
+    return (uchar *)(((quintptr)address + alignmentMask) & ~alignmentMask);
+}
+
 void QRasterPaintEnginePrivate::rasterize(QT_FT_Outline *outline,
                                           ProcessSpans callback,
                                           void *userData, QRasterBuffer *)
@@ -3791,19 +3796,10 @@ void QRasterPaintEnginePrivate::rasterize(QT_FT_Outline *outline,
     // minimize memory reallocations. However if initial size for
     // raster pool is changed for lower value, reallocations will
     // occur normally.
-    const int rasterPoolInitialSize = MINIMUM_POOL_SIZE;
-    int rasterPoolSize = rasterPoolInitialSize;
-    unsigned char *rasterPoolBase;
-#if defined(Q_WS_WIN64)
-    rasterPoolBase =
-        // We make use of setjmp and longjmp in qgrayraster.c which requires
-        // 16-byte alignment, hence we hardcode this requirement here..
-        (unsigned char *) _aligned_malloc(rasterPoolSize, sizeof(void*) * 2);
-#else
-    unsigned char rasterPoolOnStack[rasterPoolInitialSize];
-    rasterPoolBase = rasterPoolOnStack;
-#endif
-    Q_CHECK_PTR(rasterPoolBase);
+    int rasterPoolSize = MINIMUM_POOL_SIZE;
+    uchar rasterPoolOnStack[MINIMUM_POOL_SIZE + 0xf];
+    uchar *rasterPoolBase = alignAddress(rasterPoolOnStack, 0xf);
+    uchar *rasterPoolOnHeap = 0;
 
     qt_ft_grays_raster.raster_reset(*grayRaster.data(), rasterPoolBase, rasterPoolSize);
 
@@ -3839,31 +3835,20 @@ void QRasterPaintEnginePrivate::rasterize(QT_FT_Outline *outline,
 
         // Out of memory, reallocate some more and try again...
         if (error == -6) { // ErrRaster_OutOfMemory from qgrayraster.c
-            int new_size = rasterPoolSize * 2;
-            if (new_size > 1024 * 1024) {
+            rasterPoolSize *= 2;
+            if (rasterPoolSize > 1024 * 1024) {
                 qWarning("QPainter: Rasterization of primitive failed");
                 break;
             }
 
             rendered_spans += q_gray_rendered_spans(*grayRaster.data());
 
-#if defined(Q_WS_WIN64)
-            _aligned_free(rasterPoolBase);
-#else
-            if (rasterPoolBase != rasterPoolOnStack) // initially on the stack
-                free(rasterPoolBase);
-#endif
+            free(rasterPoolOnHeap);
+            rasterPoolOnHeap = (uchar *)malloc(rasterPoolSize + 0xf);
 
-            rasterPoolSize = new_size;
-            rasterPoolBase =
-#if defined(Q_WS_WIN64)
-                // We make use of setjmp and longjmp in qgrayraster.c which requires
-                // 16-byte alignment, hence we hardcode this requirement here..
-                (unsigned char *) _aligned_malloc(rasterPoolSize, sizeof(void*) * 2);
-#else
-                (unsigned char *) malloc(rasterPoolSize);
-#endif
-            Q_CHECK_PTR(rasterPoolBase); // note: we just freed the old rasterPoolBase. I hope it's not fatal.
+            Q_CHECK_PTR(rasterPoolOnHeap); // note: we just freed the old rasterPoolBase. I hope it's not fatal.
+
+            rasterPoolBase = alignAddress(rasterPoolOnHeap, 0xf);
 
             qt_ft_grays_raster.raster_done(*grayRaster.data());
             qt_ft_grays_raster.raster_new(grayRaster.data());
@@ -3873,12 +3858,7 @@ void QRasterPaintEnginePrivate::rasterize(QT_FT_Outline *outline,
         }
     }
 
-#if defined(Q_WS_WIN64)
-    _aligned_free(rasterPoolBase);
-#else
-    if (rasterPoolBase != rasterPoolOnStack) // initially on the stack
-        free(rasterPoolBase);
-#endif
+    free(rasterPoolOnHeap);
 }
 
 void QRasterPaintEnginePrivate::recalculateFastImages()