1. A method comprising: receiving a bus message in a first cache, the bus message corresponding to a speculative access to a portion of a second cache by a second thread and without communication of a speculative value of the second cache portion; and dynamically determining in the first cache if an inter-thread dependency exists between the second thread and a first thread associated with the first cache with respect to the portion, including comparing a first mask of the bus message to a first mask of a cache line of the first cache including the portion, the first mask indicative of one or more speculative accesses to the portion, and determining the inter-thread dependency based on the comparison.