Apparatus, method, and system for providing a decision mechanism for conditional commits in an atomic region

An apparatus for optimizing code comprising:na memory to hold program code; anda processor including,hardware resources adapted to support transactional execution and to provide a representation of an availability of the hardware resources; andexecution logic adapted to execute the program code to cause the processor to dynamically resize a transactional region including an optimized portion of the program code based on the representation of the availability of the hardware resources.

An apparatus comprising:ndecode logic adapted to decode a region check instruction associated with a transaction; andhardware adapted to support execution of the transaction, wherein the hardware is further adapted to provide a representation of a hardware usage metric to a usage metric storage element in response to the decode logic decoding the region check instruction, wherein the usage metric storage element is adapted to be utilized in determining if a conditional commit of the transaction is to be performed before an end of the transaction.

An apparatus comprising:ndecode logic adapted to decode a conditional commit instruction to be associated with a conditional commit point in a transaction, the conditional commit instruction to reference a destination address; andhardware adapted to determine, in response to the decode logic decoding the conditional commit instruction, if a hardware resource is to include enough available space to support execution of a region of the transaction and to jump execution to the destination address in response to determining the hardware does not include enough available space to support execution of the region of the transaction.

A system comprising:na memory adapted to hold program code, the program code to include an atomic region with optimized code comprising a conditional commit instruction before an end of the atomic region; anda processor coupled to the memory, the processor including decode logic adapted to recognize the commit instruction and hardware adapted to determine, in response to the decode logic recognizing the conditional commit instruction, if the atomic region should be committed before the end of the atomic region.

An apparatus comprising:nexecution logic adapted to execute a transaction including a loop;a counter adapted to count a number of iterations of the loop; andhardware adapted to initiate a commit of a transaction before the end of the transaction in response to the number of iterations reaching an iteration, wherein the iteration threshold is to be initially set to a default value, to be increased in response to no roll-backs due to hardware constraints before the hardware initiates a commit of the transaction before the end of the transaction in response to the counter reaching the default value, and to be decreased in response to a roll-back due to hardware constraints before the hardware initiates a commit of the transaction before the end of the transaction in response to the counter reaching the default value, and wherein the default value is selected from a group of values consisting of a number of speculative stores in the loop, a number of entries available in a memory device divided by a number of entries estimated to be utilized during an iteration of the loop, a start value from software, and a number of loop iterations before a roll-back due to hardware constraints during a previous execution loop.