PIPELINE REPLAY SUPPORT FOR MULTI-CYCLE OPERATIONS

Instructions asserted in the instruction pipeline (3) of the microprocessor are accompanied by control information, comprising a group of bits, asserted within a control information pipeline (15) of the processor. The control information pipeline is synchronized to the instruction pipeline so that the control information for an instruction progresses in synchronism with the instruction. The control information may identify, directly or indirectly, the type of operation called for by the instruction and, if the operation is to be performed in parts, indicate the part to be performed. Means are included in to the processor, such as a number of functional execution units (7), to interpret that control information and take appropriate action. Applied in a VLIW processor to an atom operation that requires multiple cycles to complete, in which the first part of the operation is permitted to complete and the atom then reasserted, the control information identifies the second assertion of the atom as the second part of a multi-cycle operation.