HeteroGen: Automatic Synthesis of Heterogeneous Cache Coherence Protocols.

We address the two challenges architects face when designing heterogeneous processors with cache-coherent shared memory. First, we introduce HeteroGen, an automated tool for composing clusters of cores, each with its own coherence protocol. Second, we show that the output of HeteroGen conforms to a precisely defined memory consistency model that we call a compound consistency model. We also demonstrate that HeteroGen can correctly fuse a wide range of coherence protocols. Our experiments indicate that protocols generated by HeteroGen perform comparably to a publicly available manually generated heterogeneous protocol.