Abstract: Methods and apparatus to provide transactional memory execution in out-of-order processors are described. In one embodiment, a stored value corresponds to the number of transactional memory access requests that are uncommitted. The stored value may be used to provide nested recovery in case of an error, fault, etc. in accordance with a described embodiment.

Abstract: Methods and apparatus to provide transactional memory execution in a virtualized mode are described. In one embodiment, data corresponding to a transactional memory access request may be stored in a portion of a memory after an operation corresponding to the transactional memory access request causes an overflow and a stored value may be updated for an occurrence of the overflow.

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: 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: A method and apparatus for setting aside a long-latency micro-operation from a reorder buffer is disclosed. In one embodiment, a long-latency micro-operation would conventionally stall a reorder buffer. Therefore a secondary buffer may be used to temporarily store that long-latency micro-operation, and other micro-operations depending from it, until that long-latency micro-operation is ready to execute. These micro-operations may then be reintroduced into the reorder buffer for execution. The use of poisoned bits may be used to ensure correct retirement of register values merged from both pre- and post-execution of the micro-operations which were set aside in the secondary buffer.

Abstract: Embodiments of the present invention relate to a system and method for comparatively increasing processor throughput and relieving pressure on the processor's scheduler and register file by diverting instructions dependent on long-latency operations from a flow of the processor pipeline and re-introducing the instructions into the flow when the long-latency operations are completed. In this way, the instructions do not tie up resources and overall instruction throughput in the pipeline is comparatively increased. Before the instructions are diverted from the pipeline, they may undergo a conventional process to map logical registers of the instructions to physical registers. Before the instructions are re-introduced into the pipeline, the physical registers mapped according to the conventional process may be re-mapped to other physical registers, thereby efficiently preserving correct program sequence information.

Abstract: Embodiments of the present invention relate to a system and method for comparatively increasing processor throughput and relieving pressure on the processor's scheduler and register file by diverting instructions dependent on long-latency operations from a flow of the processor pipeline and re-introducing them into the flow when the long-latency operations are completed. In this way, the instructions do not tie up resources and overall instruction throughput in the pipeline is comparatively increased.

Abstract: A method and apparatus for executing a selective recovery after a branch misprediction is disclosed. In one embodiment, the instructions following the mispredicted branch point may be saved for selective re-execution in a buffer. Those instructions that wrote to physical registers between the mispredicted branch point and an exact convergence point, thereby causing false data dependencies, may be followed by corresponding move instructions to eliminate the false data dependencies. The instructions subsequent to the exact convergence point may then be selectively re-executed if subject to the previous false data dependencies.

Abstract: A single-version data cache processes speculative stores using one or more checkpoints.

Abstract: A processor enabled with checkpoints may be used to recover registers using counter entry and release.

Abstract: Checkpoints may be used to recover from branch mispredictions using scalable rename map table recovery.

Abstract: In one embodiment of the invention, a processor includes an execution pipeline to concurrently execute at least portions of threads, wherein at least one of the threads is dependent on at least another one of the threads. The processor also includes detection circuitry to detect speculation errors in the execution of the threads. In another embodiment, the processor includes thread management logic to control dynamic creation of threads from a program.

Abstract: A prioritized content addressable memory having an at most one hit property despite the presence of redundant values stored therein. Redundant values within the content addressable memory are prioritized prior to performing value matching. Value matching of input data is performed only against any unique values and any highest ranked redundant value stored in the content addressable memory.

Abstract: A prioritized content addressable memory having an at most one hit property despite the presence of redundant values stored therein. Redundant values within the content addressable memory are prioritized prior to performing value matching. Value matching of input data is performed only against any unique values and any highest ranked redundant value stored in the content addressable memory.

Abstract: A memory disambiguation apparatus includes a store queue, a store forwarding buffer, and a version count buffer. The store queue includes an entry for each store instruction in the instruction window of a processor. Some store queue entries include resolved store addresses, and some do not. The store forwarding buffer is a set-associative buffer that has entries allocated for store instructions as store addresses are resolved. Each entry in the store forwarding buffer is allocated into a set determined in part by a subset of the store address. When the set in the store forwarding buffer is full, an older entry in the set is discarded in favor of the newly allocated entry. A version count buffer including an array of overflow indicators is maintained to track overflow occurrences. As load addresses are resolved for load instructions in the instruction window, the set-associative store forwarding buffer can be searched to provide memory disambiguation.

Abstract: A prioritized content addressable memory having an at most one hit property despite the presence of redundant values stored therein. Redundant values within the content addressable memory are prioritized prior to performing value matching. Value matching of input data is performed only against any unique values and any highest ranked redundant value stored in the content addressable memory.

Abstract: A memory disambiguation apparatus includes a store queue, a store forwarding buffer, and a version count buffer. The store queue includes an entry for each store instruction in the instruction window of a processor. Some store queue entries include resolved store addresses, and some do not. The store forwarding buffer is a set-associative buffer that has entries allocated for store instructions as store addresses are resolved. Each entry in the store forwarding buffer is allocated into a set determined in part by a subset of the store address. When the set in the store forwarding buffer is full, an older entry in the set is discarded in favor of the newly allocated entry. A version count buffer including an array of overflow indicators is maintained to track overflow occurrences. As load addresses are resolved for load instructions in the instruction window, the set-associative store forwarding buffer can be searched to provide memory disambiguation.

Abstract: In one embodiment of the invention, a processor includes an execution pipeline to concurrently execute at least portions of threads, wherein at least one of the threads is dependent on at least another one of the threads. The processor also includes detection circuitry to detect speculation errors in the execution of the threads. In another embodiment, the processor includes thread management logic to control dynamic creation of threads from a program.

Abstract: A prioritized content addressable memory having an at most one hit property despite the presence of redundant values stored therein. Redundant values within the content addressable memory are prioritized prior to performing value matching. Value matching of input data is performed only against any unique values and any highest ranked redundant value stored in the content addressable memory.

Abstract: A device is presented including a first processor and a second processor. A number of memory devices are connected to the first processor and the second processor. A register buffer is connected to the first processor and the second processor. A trace buffer is connected to the first processor and the second processor. A number of memory instruction buffers are connected to the first processor and the second processor. The first processor and the second processor perform single threaded applications using multithreading resources. A method is also presented where a first thread is executed from a first processor. The first thread is also executed from a second processor as directed by the first processor. The second processor executes instructions ahead of the first processor.