1 files changed, 130 insertions, 0 deletions
diff --git a/Source/JavaScriptCore/domjit/DOMJITHeapRange.h b/Source/JavaScriptCore/domjit/DOMJITHeapRange.h
new file mode 100644
index 000000000..aab02bf01
--- /dev/null
+++ b/Source/JavaScriptCore/domjit/DOMJITHeapRange.h
@@ -0,0 +1,130 @@
+/*
+ * Copyright (C) 2016 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <wtf/MathExtras.h>
+#include <wtf/PrintStream.h>
+
+namespace JSC { namespace DOMJIT {
+
+class HeapRange {
+public:
+    constexpr HeapRange()
+        : m_begin(UINT16_MAX)
+        , m_end(UINT16_MAX)
+    {
+    }
+
+    HeapRange(uint16_t begin, uint16_t end)
+        : m_begin(begin)
+        , m_end(end)
+    {
+        ASSERT_WITH_MESSAGE(begin <= end, "begin <= end is the invariant of this HeapRange.");
+    }
+
+    enum ConstExprTag { ConstExpr };
+    constexpr HeapRange(ConstExprTag, uint16_t begin, uint16_t end)
+        : m_begin(begin)
+        , m_end(end)
+    {
+    }
+
+    enum RawRepresentationTag { RawRepresentation };
+    explicit constexpr HeapRange(RawRepresentationTag, uint32_t value)
+        : m_raw(value)
+    {
+    }
+
+    constexpr static HeapRange fromRaw(uint32_t value)
+    {
+        return HeapRange(RawRepresentation, value);
+    }
+
+    uint16_t begin() const { return m_begin; }
+    uint16_t end() const { return m_end; }
+    uint32_t rawRepresentation() { return m_raw; }
+
+    constexpr explicit operator bool() const
+    {
+        return m_begin != m_end;
+    }
+
+    constexpr bool operator==(const HeapRange& other) const
+    {
+        return m_begin == other.m_begin && m_end == other.m_end;
+    }
+
+    constexpr bool operator!=(const HeapRange& other) const
+    {
+        return !operator==(other);
+    }
+
+    template<uint16_t begin, uint16_t end>
+    static constexpr HeapRange fromConstant()
+    {
+        static_assert(begin < end || (begin == UINT16_MAX && end == UINT16_MAX), "begin < end or the both are UINT16_MAX is the invariant of this HeapRange.");
+        return HeapRange(ConstExpr, begin, end);
+    }
+
+    static constexpr HeapRange top() { return fromConstant<0, UINT16_MAX>(); }
+    static constexpr HeapRange none() { return fromConstant<UINT16_MAX, UINT16_MAX>(); } // Empty range.
+
+    bool isStrictSubtypeOf(const HeapRange& other) const
+    {
+        if (!*this || !other)
+            return false;
+        if (*this == other)
+            return false;
+        return other.m_begin <= m_begin && m_end <= other.m_end;
+    }
+
+    bool isSubtypeOf(const HeapRange& other) const
+    {
+        if (!*this || !other)
+            return false;
+        if (*this == other)
+            return true;
+        return isStrictSubtypeOf(other);
+    }
+
+    bool overlaps(const HeapRange& other) const
+    {
+        return WTF::rangesOverlap(m_begin, m_end, other.m_begin, other.m_end);
+    }
+
+    JS_EXPORT_PRIVATE void dump(PrintStream&) const;
+
+private:
+    union {
+        struct {
+            uint16_t m_begin;
+            uint16_t m_end;
+        };
+        uint32_t m_raw;
+    };
+};
+
+} }