Method and apparatus for flexible, accurate, and/or efficient code profiling

An apparatus implemented at least partially in hardware processor for profiling program code comprising:

• a filtering component identifying a first set of instructions for which profiling is desired wherein, in response to detecting that an instruction has been retired, wherein the first set of the instructions comprises a subset of all instructions, wherein each of the first set of instructions is associated with profiling events, wherein the filtering component determines whether the instruction is within the first set of instructions for which profiling is desired, and wherein identifying the first set of the instructions comprises specifying a particular address range and identifying instructions within the address range as being instructions for which profiling is desired;
• an event selection component detecting an event in response to the instruction retiring, the event selection component generating event signals in response to a designated event;
• and
• a profiling component recording the occurrence or not occurrence of the event within a first storage device responsive to signals from the filtering component and/or the event selection component upon an indication indicating the first storage device is not saturated, wherein the first storage device is a register having an entry for each of a plurality of instruction and event pairs, each entry recording a number of occurrences and a number of not occurrence of a particular event for a particular instruction.

A computer system comprising:

• a display device;
• a memory for storing instructions;
• a processor for processing the instructions;
• and
• an apparatus for profiling program code implemented at least partially in hardware processor comprising:
• a filtering component identifying a first set of instructions for which profiling is desired wherein, in response to detecting that an instruction has been retired, wherein the first set of the instructions comprises a subset of all instructions, wherein each of the first set of instructions is associated with profiling events, wherein the filtering component determines whether the instruction is within the first set of instructions for which profiling is desired, and wherein identifying the first set of the instructions comprises specifying a particular address range and identifying instructions within the address range as being instructions for which profiling is desired;
• an event selection component detecting an event in response to the instruction retiring, the event selection component generating event signals in response to a designated event;
• and
• a profiling component recording the occurrence or not occurrence of the event within a first storage device responsive to signals from the filtering component and/or the event selection component upon an indication indicating the first storage device is not saturated, wherein the first storage device is a register having an entry for each of a plurality of instruction and event pairs, each entry recording a number of occurrences and a number of not occurrence of a particular event for a particular instruction.