1 files changed, 116 insertions, 0 deletions
diff --git a/gfx/angle/checkout/src/libANGLE/IndexRangeCache.cpp b/gfx/angle/checkout/src/libANGLE/IndexRangeCache.cpp
new file mode 100644
index 0000000000..d16b2bd9c7
--- /dev/null
+++ b/gfx/angle/checkout/src/libANGLE/IndexRangeCache.cpp
@@ -0,0 +1,116 @@
+//
+// Copyright 2013 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
+// IndexRangeCache.cpp: Defines the gl::IndexRangeCache class which stores information about
+// ranges of indices.
+
+#include "libANGLE/IndexRangeCache.h"
+
+#include "common/debug.h"
+#include "libANGLE/formatutils.h"
+
+namespace gl
+{
+
+IndexRangeCache::IndexRangeCache() {}
+
+IndexRangeCache::~IndexRangeCache() {}
+
+void IndexRangeCache::addRange(DrawElementsType type,
+                               size_t offset,
+                               size_t count,
+                               bool primitiveRestartEnabled,
+                               const IndexRange &range)
+{
+    mIndexRangeCache[IndexRangeKey(type, offset, count, primitiveRestartEnabled)] = range;
+}
+
+bool IndexRangeCache::findRange(DrawElementsType type,
+                                size_t offset,
+                                size_t count,
+                                bool primitiveRestartEnabled,
+                                IndexRange *outRange) const
+{
+    auto i = mIndexRangeCache.find(IndexRangeKey(type, offset, count, primitiveRestartEnabled));
+    if (i != mIndexRangeCache.end())
+    {
+        if (outRange)
+        {
+            *outRange = i->second;
+        }
+        return true;
+    }
+    else
+    {
+        if (outRange)
+        {
+            *outRange = IndexRange();
+        }
+        return false;
+    }
+}
+
+void IndexRangeCache::invalidateRange(size_t offset, size_t size)
+{
+    size_t invalidateStart = offset;
+    size_t invalidateEnd   = offset + size;
+
+    auto i = mIndexRangeCache.begin();
+    while (i != mIndexRangeCache.end())
+    {
+        size_t rangeStart = i->first.offset;
+        size_t rangeEnd =
+            i->first.offset + (GetDrawElementsTypeSize(i->first.type) * i->first.count);
+
+        if (invalidateEnd < rangeStart || invalidateStart > rangeEnd)
+        {
+            ++i;
+        }
+        else
+        {
+            mIndexRangeCache.erase(i++);
+        }
+    }
+}
+
+void IndexRangeCache::clear()
+{
+    mIndexRangeCache.clear();
+}
+
+IndexRangeCache::IndexRangeKey::IndexRangeKey()
+    : IndexRangeCache::IndexRangeKey(DrawElementsType::InvalidEnum, 0, 0, false)
+{}
+
+IndexRangeCache::IndexRangeKey::IndexRangeKey(DrawElementsType type_,
+                                              size_t offset_,
+                                              size_t count_,
+                                              bool primitiveRestartEnabled_)
+    : type(type_), offset(offset_), count(count_), primitiveRestartEnabled(primitiveRestartEnabled_)
+{}
+
+bool IndexRangeCache::IndexRangeKey::operator<(const IndexRangeKey &rhs) const
+{
+    if (type != rhs.type)
+    {
+        return type < rhs.type;
+    }
+    if (offset != rhs.offset)
+    {
+        return offset < rhs.offset;
+    }
+    if (count != rhs.count)
+    {
+        return count < rhs.count;
+    }
+    if (primitiveRestartEnabled != rhs.primitiveRestartEnabled)
+    {
+        return primitiveRestartEnabled;
+    }
+    return false;
+}
+
+}  // namespace gl