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Docs: Shorten cmd:ref

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Krystine Sherwin 2024-05-03 13:16:48 +12:00
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docs/source/using_yosys/synthesis/fsm.rst
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@ -1,14 +1,14 @@
FSM handling
============
The :cmd:ref:`fsm` command identifies, extracts, optimizes (re-encodes), and
The `fsm` command identifies, extracts, optimizes (re-encodes), and
re-synthesizes finite state machines. It again is a macro that calls a series of
other commands:
.. literalinclude:: /code_examples/macro_commands/fsm.ys
:language: yoscrypt
:start-after: #end:
:caption: Passes called by :cmd:ref:`fsm`
:caption: Passes called by `fsm`
See also :doc:`/cmd/fsm`.
@ -18,7 +18,7 @@ general reported technique :cite:p:`fsmextract`.
FSM detection
~~~~~~~~~~~~~
The :cmd:ref:`fsm_detect` pass identifies FSM state registers. It sets the
The `fsm_detect` pass identifies FSM state registers. It sets the
``\fsm_encoding = "auto"`` attribute on any (multi-bit) wire that matches the
following description:
@ -44,7 +44,7 @@ results.
FSM extraction
~~~~~~~~~~~~~~
The :cmd:ref:`fsm_extract` pass operates on all state signals marked with the
The `fsm_extract` pass operates on all state signals marked with the
(``\fsm_encoding != "none"``) attribute. For each state signal the following
information is determined:
@ -87,7 +87,7 @@ given set of result signals using a set of signal-value assignments. It can also
be passed a list of stop-signals that abort the ConstEval algorithm if the value
of a stop-signal is needed in order to calculate the result signals.
The :cmd:ref:`fsm_extract` pass uses the ConstEval class in the following way to
The `fsm_extract` pass uses the ConstEval class in the following way to
create a transition table. For each state:
1. Create a ConstEval object for the module containing the FSM
@ -108,12 +108,12 @@ drivers for the control outputs are disconnected.
FSM optimization
~~~~~~~~~~~~~~~~
The :cmd:ref:`fsm_opt` pass performs basic optimizations on `$fsm` cells (not
The `fsm_opt` pass performs basic optimizations on `$fsm` cells (not
including state recoding). The following optimizations are performed (in this
order):
- Unused control outputs are removed from the `$fsm` cell. The attribute
``\unused_bits`` (that is usually set by the :cmd:ref:`opt_clean` pass) is
``\unused_bits`` (that is usually set by the `opt_clean` pass) is
used to determine which control outputs are unused.
- Control inputs that are connected to the same driver are merged.
@ -134,11 +134,11 @@ order):
FSM recoding
~~~~~~~~~~~~
The :cmd:ref:`fsm_recode` pass assigns new bit pattern to the states. Usually
The `fsm_recode` pass assigns new bit pattern to the states. Usually
this also implies a change in the width of the state signal. At the moment of
this writing only one-hot encoding with all-zero for the reset state is
supported.
The :cmd:ref:`fsm_recode` pass can also write a text file with the changes
The `fsm_recode` pass can also write a text file with the changes
performed by it that can be used when verifying designs synthesized by Yosys
using Synopsys Formality.