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Helper Functions

Cutting and Extending WireVectors

The functions below provide ways of combining, slicing, and extending :class:`WireVectors<.WireVector>` in ways that are often useful in hardware design. The functions below extend those member functions of the :class:`.WireVector` class itself (which provides support for the Python builtin :func:`len`, slicing e.g. wire[3:6], :meth:`~.WireVector.zero_extended`, :meth:`~.WireVector.sign_extended`, and many operators such as addition and multiplication).

.. autofunction:: pyrtl.concat

.. autofunction:: pyrtl.concat_list

.. autofunction:: pyrtl.match_bitwidth

.. autofunction:: pyrtl.truncate

.. autofunction:: pyrtl.chop

.. autofunction:: pyrtl.wire_struct

.. autofunction:: pyrtl.wire_matrix

Coercion to WireVector

:func:`.as_wires` coerces values to :class:`WireVectors<.WireVector>`. Most PyRTL helper functions and classes call :func:`.as_wires` on their inputs, to manage the mixture of constants and :class:`WireVectors<.WireVector>` that naturally occur in hardware development.

See :ref:`wirevector_coercion` for examples and more details.

.. autofunction:: pyrtl.as_wires

Control Flow Hardware

.. autofunction:: pyrtl.mux

.. autofunction:: pyrtl.select

.. autofunction:: pyrtl.enum_mux

.. autoclass:: pyrtl.helperfuncs.MatchedFields
    :members:
    :undoc-members:

.. autofunction:: pyrtl.match_bitpattern

.. autofunction:: pyrtl.bitfield_update

.. autofunction:: pyrtl.bitfield_update_set

Interpreting Vectors of Bits

Under the hood, every single value a PyRTL design operates on is a bit vector (which is, in turn, simply an integer of bounded power-of-two size. Interpreting these bit vectors as humans, and turning human understandable values into their corresponding bit vectors, can both be a bit of a pain. The functions below do not create any hardware but rather help in the process of reasoning about bit vector representations of human understandable values.

.. autofunction:: pyrtl.val_to_signed_integer

.. autoclass:: pyrtl.helperfuncs.ValueBitwidthTuple
   :members: value, bitwidth

.. autofunction:: pyrtl.infer_val_and_bitwidth

.. autofunction:: pyrtl.val_to_formatted_str

.. autofunction:: pyrtl.formatted_str_to_val

.. autofunction:: pyrtl.log2

Debugging

.. autofunction:: pyrtl.set_debug_mode

.. autofunction:: pyrtl.probe

.. autofunction:: pyrtl.rtl_assert

Reductions

.. autofunction:: pyrtl.and_all_bits

.. autofunction:: pyrtl.or_all_bits

.. autofunction:: pyrtl.xor_all_bits

.. autofunction:: pyrtl.parity

.. autofunction:: pyrtl.rtl_any

.. autofunction:: pyrtl.rtl_all

Extended Logic and Arithmetic

The functions below provide ways of comparing and arithmetically combining :class:`WireVectors<.WireVector>` in ways that are often useful in hardware design. The functions below extend those member functions of the :class:`.WireVector` class itself (which provides support for unsigned addition, subtraction, multiplication, comparison, and many others).

.. autofunction:: pyrtl.signed_add

.. autofunction:: pyrtl.signed_sub

.. autofunction:: pyrtl.signed_mult

.. autofunction:: pyrtl.signed_lt

.. autofunction:: pyrtl.signed_le

.. autofunction:: pyrtl.signed_gt

.. autofunction:: pyrtl.signed_ge

.. autofunction:: pyrtl.shift_left_logical

.. autofunction:: pyrtl.shift_left_arithmetic

.. autofunction:: pyrtl.shift_right_logical

.. autofunction:: pyrtl.shift_right_arithmetic

Encoders and Decoders

.. autofunction:: pyrtl.one_hot_to_binary

.. autofunction:: pyrtl.binary_to_one_hot