extract_reduce - converts gate chains into $reduce_* cells¶
yosys> help extract_reduce¶
extract_reduce [options] [selection]
converts gate chains into $reduce_* cells This command finds chains of $_AND_, $_OR_, and $_XOR_ cells and replaces them with their corresponding $reduce_* cells. Because this command only operates on these cell types, it is recommended to map the design to only these cell types using the `abc -g` command. Note that, in some cases, it may be more effective to map the design to only $_AND_ cells, run extract_reduce, map the remaining parts of the design to AND/OR/XOR cells, and run extract_reduce a second time.
Allows matching of cells that have loads outside the chain. These cells will be replicated and folded into the $reduce_* cell, but the original cell will remain, driving its original loads.