1. A method for allocating registers for a processor based on cycle information, the processor comprising a first cluster and a second cluster, each cluster comprising a first functional unit, a second functional unit, a first local register file connected to the first functional unit, a second local register file connected to the second functional unit, and a global register file having a ping-pong structure formed by a first register bank and a second register bank, the global register file connected to the first and second functional units, the method comprising the steps of: obtaining cycle information indicating latency dependencies of a plurality of instructions; building a graph comprising nodes, circles and edges, wherein each node represents an instruction and is either unallocated or is allocated to the first functional unit or the second functional unit, each circle is attached to a node and represents an operand or the result of an instruction, and each edge is connected between two of the circles, indicating data dependency therebetween; allocating one of the first and second functional units to the unallocated nodes in the graph according to the nodes already allocated in the path containing the nodes to be allocated and the cycle information; allocating the first, second and global register files to the circles representing the result of an instruction based on the circles connected to the circles to be allocated and the data dependency therebetween; allocating the first register bank and the second register bank to the circles allocated to the global register file according to the data dependency therebetween and the cycle information; partitioning the nodes allocated to the first functional unit and the second functional unit into a first group assigned to the first cluster and a second group assigned to the second cluster based on the cycle information; and adding at least one node to communicate between the first cluster and the second cluster or between the global register file and the first and second local register files.