Instruction stream control

An interface for requesting instructions from a data store storing instructions of a program to be executed by a data processor, and for receiving and transmitting said instructions to said data processor, said interface being for use in a processing system and comprising:

• an input configured to receive said instructions from said data store via at least one input bus;
• a buffer configured to store said received instructions;
• an output configured to output said instructions to said data processor via at least one output bus;
• a control signal input configured to receive a control signal including information about program behavior of said program;
• and
• a buffer controller configured to:
• control said buffer to request an instruction subsequent to a previously received instruction within an instruction stream of said program from said data store in response to detection of no control signal on said control signal input and to detection of available buffer storage capacity;
• and
• control at least one of input of instructions and storage of instructions within said interface in order to seek to reduce instruction movement through said input in response to a control signal received at said control signal input,
• wherein said interface further includes a configuration signal input configured to receive a configuration signal, said configuration signal indicating system conditions under which said program interacts with said processing system, and
• wherein said buffer controller is responsive to both said control signal received at said control signal input and to said configuration signal received at said configuration signal input to control said at least one of input and storage of instructions within said interface in response.