skia WIPjarred/canvas

1 files changed, 34 insertions, 0 deletions

diff --git a/src/deps/skia/include/private/SkSafe32.h b/src/deps/skia/include/private/SkSafe32.h
new file mode 100644
index 000000000..7e59f2b00
--- /dev/null
+++ b/src/deps/skia/include/private/SkSafe32.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright 2018 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkSafe32_DEFINED
+#define SkSafe32_DEFINED
+
+#include "include/core/SkTypes.h"
+
+static constexpr int32_t Sk64_pin_to_s32(int64_t x) {
+    return x < SK_MinS32 ? SK_MinS32 : (x > SK_MaxS32 ? SK_MaxS32 : (int32_t)x);
+}
+
+static constexpr int32_t Sk32_sat_add(int32_t a, int32_t b) {
+    return Sk64_pin_to_s32((int64_t)a + (int64_t)b);
+}
+
+static constexpr int32_t Sk32_sat_sub(int32_t a, int32_t b) {
+    return Sk64_pin_to_s32((int64_t)a - (int64_t)b);
+}
+
+// To avoid UBSAN complaints about 2's compliment overflows
+//
+static constexpr int32_t Sk32_can_overflow_add(int32_t a, int32_t b) {
+    return (int32_t)((uint32_t)a + (uint32_t)b);
+}
+static constexpr int32_t Sk32_can_overflow_sub(int32_t a, int32_t b) {
+    return (int32_t)((uint32_t)a - (uint32_t)b);
+}
+
+#endif