1 files changed, 63 insertions, 0 deletions
diff --git a/src/deps/skia/include/private/SkShaderCodeDictionary.h b/src/deps/skia/include/private/SkShaderCodeDictionary.h
new file mode 100644
index 000000000..1eb86fb87
--- /dev/null
+++ b/src/deps/skia/include/private/SkShaderCodeDictionary.h
@@ -0,0 +1,63 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkShaderCodeDictionary_DEFINED
+#define SkShaderCodeDictionary_DEFINED
+
+#include <unordered_map>
+#include "include/private/SkPaintParamsKey.h"
+#include "include/private/SkSpinlock.h"
+#include "include/private/SkUniquePaintParamsID.h"
+#include "src/core/SkArenaAlloc.h"
+
+class SkShaderCodeDictionary {
+public:
+    SkShaderCodeDictionary();
+
+    struct Entry {
+    public:
+        SkUniquePaintParamsID uniqueID() const {
+            SkASSERT(fUniqueID.isValid());
+            return fUniqueID;
+        }
+        const SkPaintParamsKey& paintParamsKey() const { return fPaintParamsKey; }
+
+    private:
+        friend class SkShaderCodeDictionary;
+
+        Entry(const SkPaintParamsKey& paintParamsKey) : fPaintParamsKey(paintParamsKey) {}
+
+        void setUniqueID(uint32_t newID) {
+            SkASSERT(!fUniqueID.isValid());
+            fUniqueID = SkUniquePaintParamsID(newID);
+        }
+
+        SkUniquePaintParamsID fUniqueID;  // fixed-size (uint32_t) unique ID assigned to a key
+        SkPaintParamsKey fPaintParamsKey; // variable-length paint key descriptor
+    };
+
+    const Entry* findOrCreate(const SkPaintParamsKey&) SK_EXCLUDES(fSpinLock);
+
+    const Entry* lookup(SkUniquePaintParamsID) const SK_EXCLUDES(fSpinLock);
+
+private:
+    Entry* makeEntry(const SkPaintParamsKey&);
+
+    struct Hash {
+        size_t operator()(const SkPaintParamsKey&) const;
+    };
+
+    // TODO: can we do something better given this should have write-seldom/read-often behavior?
+    mutable SkSpinlock fSpinLock;
+
+    std::unordered_map<SkPaintParamsKey, Entry*, Hash> fHash SK_GUARDED_BY(fSpinLock);
+    std::vector<Entry*> fEntryVector SK_GUARDED_BY(fSpinLock);
+
+    SkArenaAlloc fArena{256};
+};
+
+#endif // SkShaderCodeDictionary_DEFINED