diff options
Diffstat (limited to 'depends/patches/qt')
-rw-r--r-- | depends/patches/qt/fix_qpainter_non_determinism.patch | 63 |
1 files changed, 0 insertions, 63 deletions
diff --git a/depends/patches/qt/fix_qpainter_non_determinism.patch b/depends/patches/qt/fix_qpainter_non_determinism.patch deleted file mode 100644 index 44c45187c5..0000000000 --- a/depends/patches/qt/fix_qpainter_non_determinism.patch +++ /dev/null @@ -1,63 +0,0 @@ -commit 2a8f7dc6ddfc414a66491522501c1574a1343ee1 -Author: Andrew Chow <achow101-github@achow101.com> -Date: Sat Nov 21 01:11:04 2020 -0500 - - build: Fix determinism issue when building with Clang 8 - - When building Qt with LLVM/Clang 8 under -O3 (the default), we run into - a determinism issue in `qt_interset_spans`. The issue has been fixed for - LLVM/Clang 9, see - https://github.com/llvm/llvm-project/commit/db101864bdc938deb1d63fe4f7da761bd38e5cae - and https://reviews.llvm.org/D64601, however this fix was not backported - to 8.x. Once LLVM/Clang 9 is used, this patch can be dropped. - - The particular issue appears to be an optimization done by -O3 which - adds a temporary variable for `spans->y` in `qt_intersect_spans`. When - it does this, sometimes it chooses to use a 32-bit movs instruction - (movswl), and other times it chooses a 64-bit movs instruction (movswq). - By patching `qt_intersect_spans` to always make a temporary variable for - `spans->y`, we are able to sidestep this problem. - -diff --git a/qtbase/src/gui/painting/qpaintengine_raster.cpp b/qtbase/src/gui/painting/qpaintengine_raster.cpp -index 92ab6e8375..f018009e0b 100644 ---- a/qtbase/src/gui/painting/qpaintengine_raster.cpp -+++ b/qtbase/src/gui/painting/qpaintengine_raster.cpp -@@ -4128,22 +4128,23 @@ static const QSpan *qt_intersect_spans(const QClipData *clip, int *currentClip, - const QSpan *clipEnd = clip->m_spans + clip->count; - - while (available && spans < end ) { -+ const short spans_y = spans->y; - if (clipSpans >= clipEnd) { - spans = end; - break; - } -- if (clipSpans->y > spans->y) { -+ if (clipSpans->y > spans_y) { - ++spans; - continue; - } -- if (spans->y != clipSpans->y) { -- if (spans->y < clip->count && clip->m_clipLines[spans->y].spans) -- clipSpans = clip->m_clipLines[spans->y].spans; -+ if (spans_y != clipSpans->y) { -+ if (spans_y < clip->count && clip->m_clipLines[spans_y].spans) -+ clipSpans = clip->m_clipLines[spans_y].spans; - else - ++clipSpans; - continue; - } -- Q_ASSERT(spans->y == clipSpans->y); -+ Q_ASSERT(spans_y == clipSpans->y); - - int sx1 = spans->x; - int sx2 = sx1 + spans->len; -@@ -4162,7 +4163,7 @@ static const QSpan *qt_intersect_spans(const QClipData *clip, int *currentClip, - if (len) { - out->x = qMax(sx1, cx1); - out->len = qMin(sx2, cx2) - out->x; -- out->y = spans->y; -+ out->y = spans_y; - out->coverage = qt_div_255(spans->coverage * clipSpans->coverage); - ++out; - --available; - |