Conditional selection of data elements

A method of data processing apparatus comprising:

• receiving at least one conditional select instruction comprising a primary source storage element field specifying a primary source storage element, and a secondary source storage element field specifying a secondary source storage element, wherein said at least one conditional select instruction further specifies a condition and an operation to be performed on a data element within said secondary source storage element;
• decoding said at least one received conditional select instruction;
• when said at least one conditional select instruction is a conditional select increment instruction, outputting an increment control signal;
• determining whether said condition has a predetermined outcome;
• receiving at an adder said data value from said secondary source storage element and a carry in signal;
• receiving signals at a multiplexer from said primary source storage element and from an output of said adder, wherein a select signal for said multiplexer comprises said condition, such that when said condition has said predetermined outcome said multiplexer selects said output of said adder;
• in response to said increment control signal being set, setting said carry in signal and incrementing in said adder a received value from said secondary source storage element;
• when said condition has said predetermined outcome selecting said secondary source storage element and performing said operation on a data element from said selected storage element to output a resultant data element;
• and
• when said condition does not have said predetermined outcome outputting said data element within said primary source storage element as said resultant data element.

A means for processing data comprising:

• means for storing data elements in storage elements;
• means for decoding at least one conditional select instruction, said at least one conditional select instruction comprising a primary source storage element field specifying a primary source storage element, and a secondary source storage element field specifying a secondary source storage element, wherein said at least one conditional select instruction further specifies a condition and an operation to be performed on a data element from said secondary source storage element;
• means for performing data processing operations controlled by said means for decoding wherein:
• said means for performing data processing operations is responsive to said decoded at least one conditional select instruction and said condition having a predetermined outcome to perform said operation on said data element from said secondary source storage element to output a resultant data element;
• and
• said means for performing data processing operations is responsive to said decoded at least one conditional select instruction and said condition not having said predetermined outcome to output said data element within said primary source storage element as said resultant data element,
• and wherein, when said at least one conditional select instruction is a conditional select increment instruction, said means for decoding is configured to output an increment control signal;
• and
• said means for performing data processing operations comprises:
• means for adding configured to receive said data value from said secondary source storage element and a carry in signal;
• means for multiplexing configured to receive signals from said primary source storage element and from an output of said means for adding, wherein a select signal for said means for multiplexing comprises said condition, such that when said condition has said predetermined outcome said means for multiplexing selects said output of said means for adding;
• and wherein in response to said increment control signal being set, said carry in signal is set and said means for adding is configured to increment a received value from said secondary source storage element.