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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 2014
+ * Routines used by both the compiler and the expression compiler.
+ */
+
+#pragma once
+
+#include <libsolidity/CompilerContext.h>
+#include <libsolidity/ASTForward.h>
+
+namespace dev {
+namespace solidity {
+
+class Type; // forward
+
+class CompilerUtils
+{
+public:
+	CompilerUtils(CompilerContext& _context): m_context(_context) {}
+
+	/// Stores the initial value of the free-memory-pointer at its position;
+	void initialiseFreeMemoryPointer();
+	/// Copies the free memory pointer to the stack.
+	void fetchFreeMemoryPointer();
+	/// Stores the free memory pointer from the stack.
+	void storeFreeMemoryPointer();
+	/// Allocates a number of bytes in memory as given on the stack.
+	/// Stack pre: <size>
+	/// Stack post: <mem_start>
+	void allocateMemory();
+	/// Appends code that transforms memptr to (memptr - free_memptr) memptr
+	void toSizeAfterFreeMemoryPointer();
+
+	/// Loads data from memory to the stack.
+	/// @param _offset offset in memory (or calldata)
+	/// @param _type data type to load
+	/// @param _fromCalldata if true, load from calldata, not from memory
+	/// @param _padToWordBoundaries if true, assume the data is padded to word (32 byte) boundaries
+	/// @returns the number of bytes consumed in memory.
+	unsigned loadFromMemory(
+		unsigned _offset,
+		Type const& _type = IntegerType(256),
+		bool _fromCalldata = false,
+		bool _padToWordBoundaries = false
+	);
+	/// Dynamic version of @see loadFromMemory, expects the memory offset on the stack.
+	/// Stack pre: memory_offset
+	/// Stack post: value... (memory_offset+length)
+	void loadFromMemoryDynamic(
+		Type const& _type,
+		bool _fromCalldata = false,
+		bool _padToWordBoundaries = true,
+		bool _keepUpdatedMemoryOffset = true
+	);
+	/// Stores a 256 bit integer from stack in memory.
+	/// @param _offset offset in memory
+	/// @param _type type of the data on the stack
+	void storeInMemory(unsigned _offset);
+	/// Dynamic version of @see storeInMemory, expects the memory offset below the value on the stack
+	/// and also updates that. For reference types, only copies the data pointer. Fails for
+	/// non-memory-references.
+	/// @param _padToWordBoundaries if true, adds zeros to pad to multiple of 32 bytes. Array elements
+	/// are always padded (except for byte arrays), regardless of this parameter.
+	/// Stack pre: memory_offset value...
+	/// Stack post: (memory_offset+length)
+	void storeInMemoryDynamic(Type const& _type, bool _padToWordBoundaries = true);
+
+	/// Copies values (of types @a _givenTypes) given on the stack to a location in memory given
+	/// at the stack top, encoding them according to the ABI as the given types @a _targetTypes.
+	/// Removes the values from the stack and leaves the updated memory pointer.
+	/// Stack pre: <v1> <v2> ... <vn> <memptr>
+	/// Stack post: <memptr_updated>
+	/// Does not touch the memory-free pointer.
+	/// @param _padToWordBoundaries if false, all values are concatenated without padding.
+	/// @param _copyDynamicDataInPlace if true, dynamic types is stored (without length)
+	/// together with fixed-length data.
+	/// @note the locations of target reference types are ignored, because it will always be
+	/// memory.
+	void encodeToMemory(
+		TypePointers const& _givenTypes = {},
+		TypePointers const& _targetTypes = {},
+		bool _padToWordBoundaries = true,
+		bool _copyDynamicDataInPlace = false
+	);
+
+	/// Uses a CALL to the identity contract to perform a memory-to-memory copy.
+	/// Stack pre: <size> <target> <source>
+	/// Stack post:
+	void memoryCopy();
+
+	/// Appends code for an implicit or explicit type conversion. This includes erasing higher
+	/// order bits (@see appendHighBitCleanup) when widening integer but also copy to memory
+	/// if a reference type is converted from calldata or storage to memory.
+	/// If @a _cleanupNeeded, high order bits cleanup is also done if no type conversion would be
+	/// necessary.
+	void convertType(Type const& _typeOnStack, Type const& _targetType, bool _cleanupNeeded = false);
+
+	/// Creates a zero-value for the given type and puts it onto the stack. This might allocate
+	/// memory for memory references.
+	void pushZeroValue(Type const& _type);
+
+	/// Moves the value that is at the top of the stack to a stack variable.
+	void moveToStackVariable(VariableDeclaration const& _variable);
+	/// Copies an item that occupies @a _itemSize stack slots from a stack depth of @a _stackDepth
+	/// to the top of the stack.
+	void copyToStackTop(unsigned _stackDepth, unsigned _itemSize);
+	/// Moves a single stack element (with _stackDepth items on top of it) to the top of the stack.
+	void moveToStackTop(unsigned _stackDepth);
+	/// Moves a single stack element past @a _stackDepth other stack elements
+	void moveIntoStack(unsigned _stackDepth);
+	/// Removes the current value from the top of the stack.
+	void popStackElement(Type const& _type);
+	/// Removes element from the top of the stack _amount times.
+	void popStackSlots(size_t _amount);
+
+	template <class T>
+	static unsigned getSizeOnStack(std::vector<T> const& _variables);
+	static unsigned getSizeOnStack(std::vector<std::shared_ptr<Type const>> const& _variableTypes);
+
+	/// Appends code that computes tha SHA3 hash of the topmost stack element of 32 byte type.
+	void computeHashStatic();
+
+	/// Bytes we need to the start of call data.
+	///  - The size in bytes of the function (hash) identifier.
+	static const unsigned dataStartOffset;
+
+	/// Position of the free-memory-pointer in memory;
+	static const size_t freeMemoryPointer;
+
+private:
+	/// Address of the precompiled identity contract.
+	static const unsigned identityContractAddress;
+
+	/// Stores the given string in memory.
+	/// Stack pre: mempos
+	/// Stack post:
+	void storeStringData(bytesConstRef _data);
+
+	/// Appends code that cleans higher-order bits for integer types.
+	void cleanHigherOrderBits(IntegerType const& _typeOnStack);
+
+	/// Prepares the given type for storing in memory by shifting it if necessary.
+	unsigned prepareMemoryStore(Type const& _type, bool _padToWordBoundaries) const;
+	/// Loads type from memory assuming memory offset is on stack top.
+	unsigned loadFromMemoryHelper(Type const& _type, bool _fromCalldata, bool _padToWordBoundaries);
+
+	CompilerContext& m_context;
+};
+
+
+template <class T>
+unsigned CompilerUtils::getSizeOnStack(std::vector<T> const& _variables)
+{
+	unsigned size = 0;
+	for (T const& variable: _variables)
+		size += variable->getType()->getSizeOnStack();
+	return size;
+}
+
+}
+}