Abstract: Methods and apparatus to provide unbounded transactional memory systems are described. In one embodiment, an operation corresponding to a software transactional memory (STM) access may be executed if a preceding hardware transactional memory (HTM) access operation fails.

Abstract: According to one embodiment of the invention, a method comprises verifying that a cache block is not exclusively owned, and if not, transmitting a message identifying both the cache block and a caching agent requesting ownership of the cache block to a broadcast interconnect.

Abstract: Provided is a method, system, and program for coordinating access to memory locations for hardware transactional memory transactions and software transactional memory transactions. A hardware transaction executing in hardware transactional memory initiates a request to access a memory location. A fault is returned to the hardware transaction request in response to an operation by one software transaction executing in a software transactional memory.

Abstract: In a system comprising a transactional memory architecture, initiating a transactional memory based transaction and then, within the transaction, checking a lock and if the lock is free, executing a critical section.

Abstract: A system includes a processor and a size bounded first-in first-out (FIFO) memory that is connected to the processor and a display is connected to the processor. A managing process to run on the processor to manage the FIFO memory structure. The FIFO memory includes a counter portion and a value portion for each of a tail portion and a head portion, and the managing process is non-blocking. The counter portion is used as a timestamp to maintain FIFO order.

Abstract: In one embodiment, the present invention includes a predictor to predict contention of an operation to be executed in a program. The operation may be processed based on a result of the prediction, which may be based on multiple independent predictions. In one embodiment, the operation may be optimized if no contention is predicted. Other embodiments are described and claimed.

Abstract: A method, apparatus, and system are provided for performing compare and exchange operations using a sleep-wakeup mechanism. According to one embodiment, an instruction at a processor is executed to help acquire a lock on behalf of the processor. If the lock is unavailable to be acquired by the processor, the instruction is put to sleep until an event has occurred.

Abstract: A method and apparatus for executing lock instructions speculatively in an out-of-order processor are disclosed. In one embodiment, a prediction is made whether a given lock instruction will actually be contended. If not, then the lock instruction may be treated as having a normal load micro-operation which may be speculatively executed. Monitor logic may look for indications that the lock instruction is actually contended. If no such indications are found, the speculative load micro-operation and other micro-operations corresponding to the lock instruction may retire. However, if such indications are in fact found, the lock instruction may be restarted, and the prediction mechanism may be updated.

Abstract: Processor extensions and software verification to support type-safe language environments running with untrusted code. Code and data spaces are partitioned into trusted and untrusted regions. Type-safe code is loaded into the trusted region of the code space, while non-type-safe code is loaded into the untrusted region of the code space. The trusted region of the data space is allocated to the type-safe code. The untrusted region of the data space is allocated to the non-type-safe code. Hardware-based truth tables are employed for defining allowable and disallowable code sequences and memory access operations. For code sequences, allowable operations are based on the location (i.e., region) of a code sequence including a current instruction and a prior instruction. For memory access, the location of the requesting instruction and data requested are considered. Disallowed code sequence or memory access operations cause the processor to generate a safe access protection trap.

Abstract: A speculative execution capability of a processor is exposed to program control through at least one machine instruction. The at least one machine instruction may be two instructions designed to facilitate synchronization between parallel processes. According to an aspect, an instruction set architecture includes circuitry that handles a speculative execution instruction and a speculation termination instruction. The speculative execution instruction may be an instruction that takes first and second operands, causes the processor to speculatively execute additional instructions if a memory location contains a value, and causes the processor to start executing instructions from an address indicated by the second operand if a mis-speculation occurs, and the speculation termination instruction may be an instruction that causes the processor to begin retiring the additional instructions.