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docs: reflowing selections doc
Combined presentation sections with appnote sections. Moved a bunch of Yosys one-liners in-line. Better reference in interactive investigation to memdemo as a part of advanced logic cone selection (esp. because the show commands use some of the advanced features)
This commit is contained in:
Krystine Sherwin
parent
c61ab7d627
commit
8335044c35
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@ -434,16 +434,7 @@ of the module and wants to carefully read all the debug output created by the
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commands in order to spot a problem. This kind of troubleshooting is much easier
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if the circuit under investigation is encapsulated in a separate module.
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.. literalinclude:: /APPNOTE_011_Design_Investigation/memdemo.v
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:caption: ``memdemo.v``, a demo circuit for demonstrating some advanced Yosys features
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:language: verilog
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:name: memdemo_v
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Let's consider :numref:`memdemo_v`. It serves no purpose other than being a
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non-trivial circuit for demonstrating some of the advanced Yosys features. We
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synthesize the circuit using ``proc; opt; memory; opt`` and change to the
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``memdemo`` module with ``cd memdemo``. If we type :cmd:ref:`show` now we see
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the following diagram:
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Recall the ``memdemo`` design from :ref:`advanced_logic_cones`:
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.. figure:: /_images/011/memdemo_00.*
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:class: width-helper
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@ -693,10 +684,10 @@ Solving sequential SAT problems
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The SAT solver functionality in Yosys can not only be used to solve
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combinatorial problems, but can also solve sequential problems. Let's consider
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the entire memdemo module from ``memdemo.v`` (:numref:`memdemo_v` above) and
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suppose we want to know which sequence of input values for ``d`` will cause the
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output y to produce the sequence 1, 2, 3 from any initial state. Let's use the
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following command:
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the ``memdemo`` design from :ref:`advanced_logic_cones` again, and suppose we
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want to know which sequence of input values for ``d`` will cause the output y to
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produce the sequence 1, 2, 3 from any initial state. Let's use the following
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command:
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.. code-block:: yoscrypt
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@ -1,16 +1,11 @@
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Selections
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----------
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.. todo:: expand on text
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.. role:: yoscrypt(code)
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:language: yoscrypt
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Most Yosys commands make use of the "selection framework" of Yosys. It can be
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used to apply commands only to part of the design. For example:
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.. code:: yoscrypt
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delete # will delete the whole design, but
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delete foobar # will only delete the module foobar.
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The selection framework
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~~~~~~~~~~~~~~~~~~~~~~~
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The :cmd:ref:`select` command can be used to create a selection for subsequent
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commands. For example:
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@ -19,11 +14,28 @@ commands. For example:
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select foobar # select the module foobar
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delete # delete selected objects
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select -clear # reset selection (select whole design)
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Many of the examples on this page make use of the :cmd:ref:`show` command to
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visually demonstrate the effect of selections. For a more detailed look at this
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command, refer to :ref:`interactive_show`.
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Normally the :cmd:ref:`select` command overwrites a previous selection. The
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commands :yoscrypt:`select -add` and :yoscrypt:`select -del` can be used to add
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or remove objects from the current selection.
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The command :yoscrypt:`select -clear` can be used to reset the selection to the
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default, which is a complete selection of everything in the current module.
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This selection framework can also be used directly in many other commands.
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Whenever a command has ``[selection]`` as last argument in its usage help, this
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means that it will use the engine behind the :cmd:ref:`select` command to
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evaluate additional arguments and use the resulting selection instead of the
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selection created by the last :cmd:ref:`select` command.
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For example, the command :cmd:ref:`delete` will delete everything in the current
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selection; while :yoscrypt:`delete foobar` will only delete the module foobar.
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If no :cmd:ref:`select` command has been made, then the "current selection" will
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be the whole design.
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.. note:: Many of the examples on this page make use of the :cmd:ref:`show`
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command to visually demonstrate the effect of selections. For a more
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detailed look at this command, refer to :ref:`interactive_show`.
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How to make a selection
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~~~~~~~~~~~~~~~~~~~~~~~
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@ -48,7 +60,7 @@ Commands can be executed in *module/* or *design/* context. Until now all
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commands have been executed in design context. The :cmd:ref:`cd` command can be
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used to switch to module context.
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In module context all commands only effect the active module. Objects in the
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In module context, all commands only effect the active module. Objects in the
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module are selected without the ``<module_name>/`` prefix. For example:
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.. code:: yoscrypt
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@ -62,233 +74,102 @@ module are selected without the ``<module_name>/`` prefix. For example:
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cd .. # switch back to design
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Note: Most synthesis scripts never switch to module context. But it is a very
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powerful tool for interactive design investigation.
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powerful tool which we explore more in
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:doc:`/using_yosys/more_scripting/interactive_investigation`.
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Selecting by object property or type
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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Special patterns can be used to select by object property or type. For example:
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.. code:: yoscrypt
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- select all wires whose names start with ``reg_``: :yoscrypt:`select w:reg_*`
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- select all objects with the attribute ``foobar`` set: :yoscrypt:`select a:foobar`
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- select all objects with the attribute ``foobar`` set to 42: :yoscrypt:`select a:foobar=42`
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- select all modules with the attribute ``blabla`` set: :yoscrypt:`select A:blabla`
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- select all $add cells from the module foo: :yoscrypt:`select foo/t:$add`
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select w:reg_* # select all wires whose names start with reg_
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select a:foobar # select all objects with the attribute foobar set
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select a:foobar=42 # select all objects with the attribute foobar set to 42
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select A:blabla # select all modules with the attribute blabla set
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select foo/t:$add # select all $add cells from the module foo
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A complete list of pattern expressions can be found in :doc:`/cmd/select`.
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A complete list of this pattern expressions can be found in the command
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reference to the :cmd:ref:`select` command.
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Operations on selections
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~~~~~~~~~~~~~~~~~~~~~~~~
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Combining selections
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^^^^^^^^^^^^^^^^^^^^
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When more than one selection expression is used in one statement, then they are
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pushed on a stack. The final elements on the stack are combined into a union:
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The :cmd:ref:`select` command is actually much more powerful than it might seem
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at first glance. When it is called with multiple arguments, each argument is
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evaluated and pushed separately on a stack. After all arguments have been
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processed it simply creates the union of all elements on the stack. So
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:yoscrypt:`select t:$add a:foo` will select all ``$add`` cells and all objects
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with the ``foo`` attribute set:
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.. code:: yoscrypt
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.. literalinclude:: /APPNOTE_011_Design_Investigation/foobaraddsub.v
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:caption: Test module for operations on selections
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:name: foobaraddsub
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:language: verilog
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select t:$dff r:WIDTH>1 # all cells of type $dff and/or with a parameter WIDTH > 1
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.. code-block::
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:caption: Output for command ``select t:$add a:foo -list`` on :numref:`foobaraddsub`
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Special ``%``-commands can be used to combine the elements on the stack:
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yosys> select t:$add a:foo -list
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foobaraddsub/$add$foobaraddsub.v:6$3
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foobaraddsub/$sub$foobaraddsub.v:5$2
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foobaraddsub/$add$foobaraddsub.v:4$1
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.. code:: yoscrypt
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In many cases simply adding more and more stuff to the selection is an
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ineffective way of selecting the interesting part of the design. Special
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arguments can be used to combine the elements on the stack. For example the
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``%i`` arguments pops the last two elements from the stack, intersects them, and
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pushes the result back on the stack. So :yoscrypt:`select t:$add a:foo %i` will
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select all ``$add`` cells that have the ``foo`` attribute set:
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select t:$dff r:WIDTH>1 %i # all cells of type $dff *AND* with a parameter WIDTH > 1
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.. code-block::
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:caption: Output for command ``select t:$add a:foo %i -list`` on :numref:`foobaraddsub`
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yosys> select t:$add a:foo %i -list
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foobaraddsub/$add$foobaraddsub.v:4$1
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Examples for ``%``-codes (see :doc:`/cmd/select` for full list):
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Some of the special ``%``-codes:
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- ``%u``: union of top two elements on stack -- pop 2, push 1
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- ``%d``: difference of top two elements on stack -- pop 2, push 1
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- ``%i``: intersection of top two elements on stack -- pop 2, push 1
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- ``%n``: inverse of top element on stack -- pop 1, push 1
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See :doc:`/cmd/select` for the full list.
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Expanding selections
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^^^^^^^^^^^^^^^^^^^^
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Selections of cells and wires can be expanded along connections using
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``%``-codes for selecting input cones (``%ci``), output cones (``%co``), or
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both (``%x``).
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The listing in :numref:`sumprod` uses the Yosys non-standard ``{... *}`` syntax
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to set the attribute ``sumstuff`` on all cells generated by the first assign
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statement. (This works on arbitrary large blocks of Verilog code an can be used
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to mark portions of code for analysis.)
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.. code:: yoscrypt
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# select all wires that are inputs to $add cells
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select t:$add %ci w:* %i
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Additional constraints such as port names can be specified.
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.. code:: yoscrypt
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# select all wires that connect a "Q" output with a "D" input
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select c:* %co:+[Q] w:* %i c:* %ci:+[D] w:* %i %i
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# select the multiplexer tree that drives the signal 'state'
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select state %ci*:+$mux,$pmux[A,B,Y]
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See :doc:`/cmd/select` for full documentation of these expressions.
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Incremental selection
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^^^^^^^^^^^^^^^^^^^^^
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Sometimes a selection can most easily be described by a series of add/delete
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operations. The commands ``select -add`` and ``select -del`` respectively add or
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remove objects from the current selection instead of overwriting it.
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.. code:: yoscrypt
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select -none # start with an empty selection
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select -add reg_* # select a bunch of objects
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select -del reg_42 # but not this one
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select -add state %ci # and add more stuff
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Within a select expression the token ``%`` can be used to push the previous selection
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on the stack.
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.. code:: yoscrypt
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select t:$add t:$sub # select all $add and $sub cells
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select % %ci % %d # select only the input wires to those cells
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Creating selection variables
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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Selections can be stored under a name with the ``select -set <name>``
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command. The stored selections can be used in later select expressions
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using the syntax ``@<name>``.
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.. code:: yoscrypt
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select -set cone_a state_a %ci*:-$dff # set @cone_a to the input cone of state_a
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select -set cone_b state_b %ci*:-$dff # set @cone_b to the input cone of state_b
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select @cone_a @cone_b %i # select the objects that are in both cones
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Remember that select expressions can also be used directly as arguments to most
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commands. Some commands also except a single select argument to some options.
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In those cases selection variables must be used to capture more complex selections.
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.. code:: yoscrypt
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dump @cone_a @cone_b
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select -set cone_ab @cone_a @cone_b %i
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show -color red @cone_ab -color magenta @cone_a -color blue @cone_b
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Example:
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.. literalinclude:: ../../../resources/PRESENTATION_ExAdv/select.v
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:language: verilog
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:caption: ``docs/resources/PRESENTATION_ExAdv/select.v``
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.. literalinclude:: ../../../resources/PRESENTATION_ExAdv/select.ys
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:language: yoscrypt
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:caption: ``docs/resources/PRESENTATION_ExAdv/select.ys``
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.. figure:: /_images/res/PRESENTATION_ExAdv/select.*
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:class: width-helper
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.. todo:: combine below sections into above where possible
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Working with selections
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~~~~~~~~~~~~~~~~~~~~~~~
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.. figure:: /_images/011/example_03.*
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:class: width-helper
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:name: seladd
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Output of :cmd:ref:`show` after ``select $2`` or ``select t:$add`` (see also
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:numref:`example_out`)
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But for most interactive work we want to further narrow the set of selected
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objects. This can be done using the :cmd:ref:`select` command.
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For example, if the command ``select $2`` is executed, a subsequent
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:cmd:ref:`show` command will yield the diagram shown in :numref:`seladd`. Note
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that the nets are now displayed in ellipses. This indicates that they are not
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selected, but only shown because the diagram contains a cell that is connected
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to the net. This of course makes no difference for the circuit that is shown,
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but it can be a useful information when manipulating selections.
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Objects can not only be selected by their name but also by other properties. For
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example ``select t:$add`` will select all cells of type ``$add``. In this case
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this is also yields the diagram shown in :numref:`seladd`.
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.. literalinclude:: ../APPNOTE_011_Design_Investigation/foobaraddsub.v
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:caption: Test module for operations on selections
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:name: foobaraddsub
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:language: verilog
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The output of ``help select`` contains a complete syntax reference for
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matching different properties.
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Many commands can operate on explicit selections. For example the command ``dump
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t:$add`` will print information on all ``$add`` cells in the active module.
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Whenever a command has ``[selection]`` as last argument in its usage help, this
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means that it will use the engine behind the :cmd:ref:`select` command to
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evaluate additional arguments and use the resulting selection instead of the
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selection created by the last :cmd:ref:`select` command.
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Normally the :cmd:ref:`select` command overwrites a previous selection. The
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commands ``select -add`` and ``select -del`` can be used to add or remove
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objects from the current selection.
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The command ``select -clear`` can be used to reset the selection to the default,
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which is a complete selection of everything in the current module.
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Operations on selections
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~~~~~~~~~~~~~~~~~~~~~~~~
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.. literalinclude:: ../APPNOTE_011_Design_Investigation/sumprod.v
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.. literalinclude:: /APPNOTE_011_Design_Investigation/sumprod.v
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:caption: Another test module for operations on selections
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:name: sumprod
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:language: verilog
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Selecting ``a:sumstuff`` in this module will yield the following circuit
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diagram:
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.. figure:: /_images/011/sumprod_00.*
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:class: width-helper
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:name: sumprod_00
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Output of ``show a:sumstuff`` on :numref:`sumprod`
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The :cmd:ref:`select` command is actually much more powerful than it might seem
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on the first glimpse. When it is called with multiple arguments, each argument
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is evaluated and pushed separately on a stack. After all arguments have been
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processed it simply creates the union of all elements on the stack. So the
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following command will select all ``$add`` cells and all objects with the
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``foo`` attribute set:
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.. code-block:: yoscrypt
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select t:$add a:foo
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(Try this with the design shown in :numref:`foobaraddsub`. Use the ``select
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-list`` command to list the current selection.)
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In many cases simply adding more and more stuff to the selection is an
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ineffective way of selecting the interesting part of the design. Special
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arguments can be used to combine the elements on the stack. For example
|
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the ``%i`` arguments pops the last two elements from the stack, intersects
|
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them, and pushes the result back on the stack. So the following command
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will select all ``$add ``cells that have the ``foo`` attribute set:
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.. code-block:: yoscrypt
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select t:$add a:foo %i
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The listing in :numref:`sumprod` uses the Yosys non-standard ``{... *}`` syntax
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to set the attribute ``sumstuff`` on all cells generated by the first assign
|
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statement. (This works on arbitrary large blocks of Verilog code an can be used
|
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to mark portions of code for analysis.)
|
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Selecting ``a:sumstuff`` in this module will yield the circuit diagram shown in
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:numref:`sumprod_00`. As only the cells themselves are selected, but not the
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temporary wire ``$1_Y``, the two adders are shown as two disjunct parts. This
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can be very useful for global signals like clock and reset signals: just
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unselect them using a command such as ``select -del clk rst`` and each cell
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using them will get its own net label.
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As only the cells themselves are selected, but not the temporary wire ``$1_Y``,
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the two adders are shown as two disjunct parts. This can be very useful for
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global signals like clock and reset signals: just unselect them using a command
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such as :yoscrypt:`select -del clk rst` and each cell using them will get its
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own net label.
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In this case however we would like to see the cells connected properly. This can
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be achieved using the ``%x`` action, that broadens the selection, i.e. for each
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selected wire it selects all cells connected to the wire and vice versa. So
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``show a:sumstuff %x`` yields the diagram shown in :numref:`sumprod_01`.
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:yoscrypt:`show a:sumstuff %x` yields the diagram shown in :numref:`sumprod_01`:
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.. figure:: /_images/011/sumprod_01.*
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:class: width-helper
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@ -297,27 +178,39 @@ selected wire it selects all cells connected to the wire and vice versa. So
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Output of ``show a:sumstuff %x`` on :numref:`sumprod`
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Selecting logic cones
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~~~~~~~~~~~~~~~~~~~~~
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^^^^^^^^^^^^^^^^^^^^^
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:numref:`sumprod_01` shows what is called the ``input cone`` of ``sum``, i.e.
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all cells and signals that are used to generate the signal ``sum``. The ``%ci``
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action can be used to select the input cones of all object in the top selection
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in the stack maintained by the :cmd:ref:`select` command.
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As the ``%x`` action, this commands broadens the selection by one "step".
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But this time the operation only works against the direction of data
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flow. That means, wires only select cells via output ports and cells
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only select wires via input ports.
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As with the ``%x`` action, this commands broadens the selection by one "step".
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But this time the operation only works against the direction of data flow. That
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means, wires only select cells via output ports and cells only select wires via
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input ports.
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:numref:`select_prod` show the sequence of diagrams generated by the following
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commands:
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The following sequence of diagrams demonstrates this step-wise expansion:
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.. code-block:: yoscrypt
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.. figure:: /_images/011/sumprod_02.*
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:class: width-helper
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show prod
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show prod %ci
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show prod %ci %ci
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show prod %ci %ci %ci
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Output of ``show prod`` on :numref:`sumprod`
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.. figure:: /_images/011/sumprod_03.*
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:class: width-helper
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Output of ``show prod %ci`` on :numref:`sumprod`
|
||||
|
||||
.. figure:: /_images/011/sumprod_04.*
|
||||
:class: width-helper
|
||||
|
||||
Output of ``show prod %ci %ci`` on :numref:`sumprod`
|
||||
|
||||
.. figure:: /_images/011/sumprod_05.*
|
||||
:class: width-helper
|
||||
|
||||
Output of ``show prod %ci %ci %ci`` on :numref:`sumprod`
|
||||
|
||||
When selecting many levels of logic, repeating ``%ci`` over and over again can
|
||||
be a bit dull. So there is a shortcut for that: the number of iterations can be
|
||||
|
|
@ -327,28 +220,28 @@ performing the ``%ci`` action three times.
|
|||
The action ``%ci*`` performs the ``%ci`` action over and over again until it
|
||||
has no effect anymore.
|
||||
|
||||
.. figure:: /_images/011/select_prod.*
|
||||
:class: width-helper
|
||||
:name: select_prod
|
||||
|
||||
Objects selected by ``select prod %ci...``
|
||||
.. _advanced_logic_cones:
|
||||
|
||||
Advanced logic cone selection
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
In most cases there are certain cell types and/or ports that should not be
|
||||
considered for the ``%ci`` action, or we only want to follow certain cell types
|
||||
and/or ports. This can be achieved using additional patterns that can be
|
||||
appended to the ``%ci`` action.
|
||||
|
||||
Lets consider the design from :numref:`memdemo_src`. It serves no purpose other
|
||||
than being a non-trivial circuit for demonstrating some of the advanced Yosys
|
||||
features. We synthesize the circuit using ``proc; opt; memory; opt`` and change
|
||||
to the ``memdemo`` module with ``cd memdemo``. If we type :cmd:ref:`show` now we
|
||||
see the diagram shown in :numref:`memdemo_00`.
|
||||
Lets consider :numref:`memdemo_src`. It serves no purpose other than being a
|
||||
non-trivial circuit for demonstrating some of the advanced Yosys features.
|
||||
|
||||
.. literalinclude:: ../APPNOTE_011_Design_Investigation/memdemo.v
|
||||
.. literalinclude:: /APPNOTE_011_Design_Investigation/memdemo.v
|
||||
:caption: Demo circuit for demonstrating some advanced Yosys features
|
||||
:name: memdemo_src
|
||||
:language: verilog
|
||||
|
||||
We synthesize the circuit using ``proc; opt; memory; opt`` and change to the
|
||||
``memdemo`` module with ``cd memdemo``. If we type :cmd:ref:`show` now we see
|
||||
the diagram shown in :numref:`memdemo_00`.
|
||||
|
||||
.. figure:: /_images/011/memdemo_00.*
|
||||
:class: width-helper
|
||||
:name: memdemo_00
|
||||
|
|
@ -377,12 +270,12 @@ cells:
|
|||
show y %ci2:+$dff[Q,D]
|
||||
|
||||
To add a pattern we add a colon followed by the pattern to the ``%ci`` action.
|
||||
The pattern it self starts with ``-`` or ``+``, indicating if it is an include
|
||||
or exclude pattern, followed by an optional comma separated list of cell types,
|
||||
The pattern itself starts with ``-`` or ``+``, indicating if it is an include or
|
||||
exclude pattern, followed by an optional comma separated list of cell types,
|
||||
followed by an optional comma separated list of port names in square brackets.
|
||||
|
||||
Since we know that the only cell considered in this case is a ``$dff`` cell,
|
||||
we could as well only specify the port names:
|
||||
Since we know that the only cell considered in this case is a ``$dff`` cell, we
|
||||
could as well only specify the port names:
|
||||
|
||||
.. code-block:: yoscrypt
|
||||
|
||||
|
|
@ -400,16 +293,16 @@ Or we could decide to tell the ``%ci`` action to not follow the ``CLK`` input:
|
|||
|
||||
Output of ``show y %ci2:+$dff[Q,D] %ci*:-$mux[S]:-$dff``
|
||||
|
||||
Next we would investigate the next logic level by adding another ``%ci2`` to
|
||||
the command:
|
||||
Next we would investigate the next logic level by adding another ``%ci2`` to the
|
||||
command:
|
||||
|
||||
.. code-block:: yoscrypt
|
||||
|
||||
show y %ci2:-[CLK] %ci2
|
||||
|
||||
From this we would learn that the next cell is a ``$mux`` cell and we would
|
||||
add additional pattern to narrow the selection on the path we are
|
||||
interested. In the end we would end up with a command such as
|
||||
From this we would learn that the next cell is a ``$mux`` cell and we would add
|
||||
additional pattern to narrow the selection on the path we are interested. In the
|
||||
end we would end up with a command such as
|
||||
|
||||
.. code-block:: yoscrypt
|
||||
|
||||
|
|
@ -429,7 +322,30 @@ boolean operations such as intersection (``%i``) and difference (``%d``) are
|
|||
powerful tools for extracting the relevant portions of the circuit under
|
||||
investigation.
|
||||
|
||||
See ``help select`` for a complete list of actions available in selections.
|
||||
Again, see :doc:`/cmd/select` for full documentation of these expressions.
|
||||
|
||||
Incremental selection
|
||||
^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
Sometimes a selection can most easily be described by a series of add/delete
|
||||
operations. As mentioned previously, the commands :yoscrypt:`select -add` and
|
||||
:yoscrypt:`select -del` respectively add or remove objects from the current
|
||||
selection instead of overwriting it.
|
||||
|
||||
.. code:: yoscrypt
|
||||
|
||||
select -none # start with an empty selection
|
||||
select -add reg_* # select a bunch of objects
|
||||
select -del reg_42 # but not this one
|
||||
select -add state %ci # and add more stuff
|
||||
|
||||
Within a select expression the token ``%`` can be used to push the previous selection
|
||||
on the stack.
|
||||
|
||||
.. code:: yoscrypt
|
||||
|
||||
select t:$add t:$sub # select all $add and $sub cells
|
||||
select % %ci % %d # select only the input wires to those cells
|
||||
|
||||
Storing and recalling selections
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
|
|
@ -437,19 +353,33 @@ Storing and recalling selections
|
|||
The current selection can be stored in memory with the command ``select -set
|
||||
<name>``. It can later be recalled using ``select @<name>``. In fact, the
|
||||
``@<name>`` expression pushes the stored selection on the stack maintained by
|
||||
the :cmd:ref:`select` command. So for example
|
||||
|
||||
.. code-block:: yoscrypt
|
||||
|
||||
select @foo @bar %i
|
||||
|
||||
the :cmd:ref:`select` command. So for example :yoscrypt:`select @foo @bar %i`
|
||||
will select the intersection between the stored selections ``foo`` and ``bar``.
|
||||
|
||||
In larger investigation efforts it is highly recommended to maintain a
|
||||
script that sets up relevant selections, so they can easily be recalled,
|
||||
for example when Yosys needs to be re-run after a design or source code
|
||||
change.
|
||||
In larger investigation efforts it is highly recommended to maintain a script
|
||||
that sets up relevant selections, so they can easily be recalled, for example
|
||||
when Yosys needs to be re-run after a design or source code change.
|
||||
|
||||
The :cmd:ref:`history` command can be used to list all recent interactive
|
||||
commands. This feature can be useful for creating such a script from the
|
||||
commands used in an interactive session.
|
||||
|
||||
Remember that select expressions can also be used directly as arguments to most
|
||||
commands. Some commands also accept a single select argument to some options. In
|
||||
those cases selection variables must be used to capture more complex selections.
|
||||
|
||||
Example:
|
||||
|
||||
.. literalinclude:: ../../../resources/PRESENTATION_ExAdv/select.v
|
||||
:language: verilog
|
||||
:caption: ``docs/resources/PRESENTATION_ExAdv/select.v``
|
||||
|
||||
.. literalinclude:: ../../../resources/PRESENTATION_ExAdv/select.ys
|
||||
:language: yoscrypt
|
||||
:caption: ``docs/resources/PRESENTATION_ExAdv/select.ys``
|
||||
:name: select_ys
|
||||
|
||||
.. figure:: /_images/res/PRESENTATION_ExAdv/select.*
|
||||
:class: width-helper
|
||||
|
||||
Circuit diagram produced by :numref:`select_ys`
|
||||
|
|
|
|||
Loading…
Reference in a new issue