Method and apparatus for configuring arbitrary sized data paths comprising multiple context processing elements

Abstract

A method and an apparatus for configuring arbitrary sized data paths comprising multiple context processing elements (MCPEs) are provided. Multiple MCPEs may be chained to form wider-word data paths of arbitrary widths. The ALUs of the data path are coupled using a carry chain for transmitting at least one carry bit from the LSB ALU to the MSB ALU. The MSB ALU comprises configurable logic for generating a signal in response to a carry bit received over the carry chain, the signal comprises a saturation signal and a saturation value. The saturation signal is generated using logic that tests for saturation in the data path. The ALUs of the data path are further coupled using a right-going carry chain for transmitting the saturation signal back down the data path. The saturation signal is transmitted from the MSB ALU through the ALUs of the data path to the LSB ALU using a first back propagation channel. A signal that selects a saturation value is transmitted from the MSB ALU to the LSB ALU using a second back propagation channel. The MCPEs of the data path use configurable logic to manipulate a resident bit sequence in response to the saturation signal transmitted thereby reconfiguring, or changing the operation of, the data path in response to the saturation signal. The carry chains support carry operations for non-local functions comprising minimum and maximum arithmetic functions.