memory_libmap - map memories to cells

yosys> help memory_libmap
memory_libmap -lib <library_file> [-D <condition>] [selection]
This pass takes a description of available RAM cell types and maps
all selected memories to one of them, or leaves them to be mapped to FFs.
-lib <library_file>
Selects a library file containing RAM cell definitions. This option
can be passed more than once to select multiple libraries.
See passes/memory/ for description of the library format.
-D <condition>
Enables a condition that can be checked within the library file
to eg. select between slightly different hardware variants.
This option can be passed any number of times.
-logic-cost-rom <num>
-logic-cost-ram <num>
Sets the cost of a single bit for memory lowered to soft logic.
Disables automatic mapping of given kind of RAMs.  Manual mapping
(using ram_style or other attributes) is still supported.