Hardware acceleration for a software transactional memory system

An apparatus comprising:

• a processor including
• a cache memory including a plurality of cache lines;
• execution resources to execute a transaction, the transaction including a first instruction to access a first cache line of the plurality of cache lines, which is associated with a first transaction field and a first lock;
• an acceleration module to
• check a state of the first lock before the access to the first cache line, if the first transaction field represents a first value,
• not check the state of the first lock before the access to the first line, if the first transaction field represents a second value, and
• set the first transaction field to represent the second value upon the access to the first cache line, if the access is the first access to the first cache line during execution of the transaction.

A system comprising:

• a multiple-resource microprocessor including a cache memory including a plurality of cache lines;
• an execution unit to execute a transaction, the transaction including a plurality of accesses to a cache line of the plurality of cache lines;
• an acceleration module to
• re-vector execution, by the execution unit, to a barrier associated with the cache line, upon a first access of the plurality of accesses to the cache line during a pendancy of the transaction, and
• allow a subsequent access of the plurality of accesses to the cache line during the pendancy of the transaction, without re-vectoring execution to the barrier associated with the cache line;
• a system memory coupled to the multi-resource microprocessor to store elements to be loaded into the plurality of cache lines in the cache memory.

A method comprising:

• executing a memory access instruction within a transaction, wherein the memory access instruction references a location in a shared memory;
• accessing the location, without determining a state of a lock mapped to the location in the shared memory, if a transaction bit associated with the location represents a first value;
• if the transaction bit associated with the location represents a second value, determining the state of the lock,
• acquiring the lock and accessing the location, if the state of the lock represents an un-owned state,
• setting the transaction bit to the first value;
• and
• generating an eviction notification, if the location is evicted and the transaction bit associated with the location represents the first value.