Quartus® Prime Standard Edition User Guide: Design Compilation

ID 683283
Date 10/22/2021
Document Table of Contents Plan Design Hierarchy and Design Files

You begin the partitioning process by planning the design hierarchy. When you assign a hierarchical instance as a design partition, the partition includes the assigned instance and entities instantiated below that are not defined as separate partitions. You can use the Merge command in the Design Partitions window to combine hierarchical partitions into a single partition, as long as they have the same immediate parent partition.
  • When planning your design hierarchy, keep logic in the “leaves” of the hierarchy instead of having logic at the top-level of the design so that you can isolate partitions if required.
  • Create entities that can form partitions of approximately equal size. For example, do not instantiate small entities at the same hierarchy level, because it is more difficult to group them to form reasonably-sized partitions.
  • Create each entity in an independent file. The Quartus® Prime software uses a file checksum to detect changes, and automatically recompiles a partition if its source file changes and its netlist type is set to either post-synthesis or post-fit. If the design entities for two partitions are defined in the same file, changes to the logic in one partition initiates recompilation for both partitions.
  • Design dependencies also affect which partitions are compiled when a source file changes. If two partitions rely on the same lower-level entity definition, changes in that lower-level entity affect both partitions. Commands such as VHDL use and Verilog HDL include create dependencies between files, so that changes to one file can trigger recompilations in all dependent files. Avoid these types of file dependencies if possible. The Partition Dependent Files report for each partition in the Analysis & Synthesis section of the Compilation report lists which files contribute to each partition.