techmap; opt
If ABC is enabled in the Yosys build configuration and a cell library is given
-in the liberty file ``mycells.lib``, the following synthesis script will synthesize
-for the given cell library:
+in the liberty file ``mycells.lib``, the following synthesis script will
+synthesize for the given cell library:
# the high-level stuff
hierarchy; proc; fsm; opt; memory; opt
- http://www.vlsitechnology.org/html/libraries.html
- http://www.vlsitechnology.org/synopsys/vsclib013.lib
-The command ``synth`` provides a good default synthesis script (see ``help synth``).
-If possible a synthesis script should borrow from ``synth``. For example:
+The command ``synth`` provides a good default synthesis script (see
+``help synth``). If possible a synthesis script should borrow from ``synth``.
+For example:
# the high-level stuff
hierarchy
command from flattening the indicated cells and modules.
- The ``init`` attribute on wires is set by the frontend when a register is
- initialized "FPGA-style" with ``reg foo = val``. It can be used during synthesis
- to add the necessary reset logic.
+ initialized "FPGA-style" with ``reg foo = val``. It can be used during
+ synthesis to add the necessary reset logic.
- The ``top`` attribute on a module marks this module as the top of the
design hierarchy. The ``hierarchy`` command sets this attribute when called
- The system task ``$anyseq`` evaluates to any value, possibly a different
value in each cycle.
-- The SystemVerilog tasks ``$past``, ``$stable``, ``$rose`` and ``$fell`` are supported
- in any clocked block.
+- The SystemVerilog tasks ``$past``, ``$stable``, ``$rose`` and ``$fell`` are
+ supported in any clocked block.
- The syntax ``@($global_clock)`` can be used to create FFs that have no
explicit clock input ($ff cells).
- The ``assume`` and ``restrict`` statements from SystemVerilog are also
supported. The same limitations as with the ``assert`` statement apply.
-- The keywords ``always_comb``, ``always_ff`` and ``always_latch``, ``logic`` and
- ``bit`` are supported.
+- The keywords ``always_comb``, ``always_ff`` and ``always_latch``, ``logic``
+ and ``bit`` are supported.
- SystemVerilog packages are supported. Once a SystemVerilog file is read
into a design with ``read_verilog``, all its packages are available to