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+/*
+	This file is part of cpp-ethereum.
+
+	cpp-ethereum is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	cpp-ethereum is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with cpp-ethereum.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @author Christian <c@ethdev.com>
+ * @date 2015
+ * Code generation utils that handle arrays.
+ */
+
+#pragma once
+
+namespace dev
+{
+namespace solidity
+{
+
+class CompilerContext;
+class Type;
+class ArrayType;
+
+/**
+ * Class that provides code generation for handling arrays.
+ */
+class ArrayUtils
+{
+public:
+	ArrayUtils(CompilerContext& _context): m_context(_context) {}
+
+	/// Copies an array to an array in storage. The arrays can be of different types only if
+	/// their storage representation is the same.
+	/// Stack pre: source_reference [source_length] target_reference
+	/// Stack post: target_reference
+	void copyArrayToStorage(ArrayType const& _targetType, ArrayType const& _sourceType) const;
+	/// Copies the data part of an array (which cannot be dynamically nested) from anywhere
+	/// to a given position in memory.
+	/// This always copies contained data as is (i.e. structs and fixed-size arrays are copied in
+	/// place as required by the ABI encoding). Use CompilerUtils::convertType if you want real
+	/// memory copies of nested arrays.
+	/// Stack pre: memory_offset source_item
+	/// Stack post: memory_offest + length(padded)
+	void copyArrayToMemory(ArrayType const& _sourceType, bool _padToWordBoundaries = true) const;
+	/// Clears the given dynamic or static array.
+	/// Stack pre: storage_ref storage_byte_offset
+	/// Stack post:
+	void clearArray(ArrayType const& _type) const;
+	/// Clears the length and data elements of the array referenced on the stack.
+	/// Stack pre: reference (excludes byte offset)
+	/// Stack post:
+	void clearDynamicArray(ArrayType const& _type) const;
+	/// Changes the size of a dynamic array and clears the tail if it is shortened.
+	/// Stack pre: reference (excludes byte offset) new_length
+	/// Stack post:
+	void resizeDynamicArray(ArrayType const& _type) const;
+	/// Appends a loop that clears a sequence of storage slots of the given type (excluding end).
+	/// Stack pre: end_ref start_ref
+	/// Stack post: end_ref
+	void clearStorageLoop(Type const& _type) const;
+	/// Converts length to size (number of storage slots or calldata/memory bytes).
+	/// if @a _pad then add padding to multiples of 32 bytes for calldata/memory.
+	/// Stack pre: length
+	/// Stack post: size
+	void convertLengthToSize(ArrayType const& _arrayType, bool _pad = false) const;
+	/// Retrieves the length (number of elements) of the array ref on the stack. This also
+	/// works for statically-sized arrays.
+	/// Stack pre: reference (excludes byte offset for dynamic storage arrays)
+	/// Stack post: reference length
+	void retrieveLength(ArrayType const& _arrayType) const;
+	/// Performs bounds checking and returns a reference on the stack.
+	/// Stack pre: reference [length] index
+	/// Stack post (storage): storage_slot byte_offset
+	/// Stack post: memory/calldata_offset
+	void accessIndex(ArrayType const& _arrayType, bool _doBoundsCheck = true) const;
+
+private:
+	/// Adds the given number of bytes to a storage byte offset counter and also increments
+	/// the storage offset if adding this number again would increase the counter over 32.
+	/// @param byteOffsetPosition the stack offset of the storage byte offset
+	/// @param storageOffsetPosition the stack offset of the storage slot offset
+	void incrementByteOffset(unsigned _byteSize, unsigned _byteOffsetPosition, unsigned _storageOffsetPosition) const;
+
+	CompilerContext& m_context;
+};
+
+}
+}