Since commit b9799b4c, the discovery mechanism for the Yosys required
to produce Verilog is different from the usual require_tool(); namely
it is possible to produce Verilog without a `yosys` binary on PATH.
Fixes#419.
This reverts commit 7fca037f9c.
This broke editable installs and has to be reverted due to a number
of pip issues:
* pypa/pip#6375
* pypa/pip#6434
* pypa/pip#6438
We can put this back once PEP 517/518 support editable installs.
Until then the legacy behavior will suffice, and we should just teach
people to install the dependencies in virtualenvs or something...
Some people's workflows involve not using `pip`. This is not
a recommended way to use nMigen, but is prevalent enough for good
enough reason that we try to keep them working anyway.
This package is deprecated and introduces a massive amount of startup
latency. On my machine with 264 installed Python packages, it reduces
the time required to `import nmigen` from ~100ms to ~200ms.
Remove _EvalContext, which was a level of indirection serving almost
no purpose. (The only case where it would be useful is repeatedly
resetting a simulation that, each time it is reset, would create new
signals to communicate with between coroutine processes. In that case
the signal states would not be persisted in _SimulatorState, but
would be removed with the _EvalContext that is recreated each time
the simulation is reset. But this could be solved with a weak map
instead.)
This regresses simulator startup time by 10-15% for unknown reasons
but is necessary to align pysim and future cxxsim.
Do not use yosys binaries with unparseable version numbers. This ensures
that nmigen always knows what version of yosys it is generating RTLIL
for.
The effect of this change is that if the version number of the system
yosys is unparsable, nmigen will attempt to fallback to the builtin
Yosys.
Fixes#409.
Preserve the original user-provided shape, while still checking
its validity. This allows Enum decoders to work when specifying
record fields with Enums.
Fixes#393.
