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-rw-r--r--depends/patches/qt/fix_qpainter_non_determinism.patch63
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;
-