Register renaming in block-based instruction set architecture

An apparatus for mapping an architectural register to a physical register can include a memory and control circuitry. The memory can be configured to store an intra-core register rename map and an inter-core register rename map. The intra-core register rename map can be configured to map the architectural register to the physical register of a core of a multi-core processor. The inter-core register rename map can be configured to relate the architectural register to an identification of the first core in response to determining that the physical register is a location of a most recent write to the architectural register that has been executed by the first core, is executing on the first core, or is expected to execute on the first core, the most recent write according to program order. The control circuitry can be configured to maintain the intra-core register rename map and the inter-core register rename map.