The $shift and $shiftx cells perform a left logical shift if the second
operand is negative. This change passes the sign of the second operand
of AST_SHIFT and AST_SHIFTX into $shift and $shiftx cells, respectively.
Includes CAD suite info and details on the OSS CAD suite nightly build targets.
Instructions for building from source, largely based on the readme but with some minor modifications.
Tests are still WIP, but we replaced the old test suites with a brief comment on the github workflow tests. Still needs more on the tests themselves and how to run them locally.
Also an extra todo on the index page.
When we are iterating over a `SigSpec`, the visited values will be of
type `SigBit` (as is the return type of `operator*()`). Account for that
in the publicly declared types.
`std::iterator` has been deprecated in C++17. Yosys is being compiled
against the C++11 standard but plugins can opt to compile against a
newer one. To silence some deprecation warnings when those plugins are
being compiled, replace the `std::iterator` inheritance with the
equivalent type declarations.
Based on the Ignite presentation and github.
Adds links for the extended Yosys universe.
Moves the original thesis stuff further down (and labels it as such).
When a plugin is being loaded from Python source, the binding will be
available under
import libyosys
That is unfortunately different from how a self-standing Python program
would import the Yosys interface, which is
from pyosys import libyosys
Until that is made consistent, at least fix the example to have it
working as is.
Moved remaining content into relevant places.
Added `load_design.rst` to more scripting.
Split fsm handling and abc out of optimization passes. Also moved things around to match the general flow previously described.
Changed generic `synth` for `prep` instead.
Replace `typical_phases.rst` and `examples.rst` with a single `example_synth.rst`.
Also updating the counter example to match.
Aims to reduce redundancy, and simplify the getting started section.
Details on things like `proc`, `memory` and `fsm` should instead be in the advanced section (under the new `synth` subsection).
The previous version could easily generate a large amount of padding
when the constant factor was significantly larger than the width of the
shift data input. This could lead to huge amounts of logic being
generated before then being optimized away at a huge performance and
memory cost.
Additionally and more critically, when the input width was not a
multiple of the constant factor, the input data was padded with 'x bits
to such a multiple before interspersing the 'x padding needed to align
the selectable windows to power-of-two offsets.
Such a final padding would not be correct for shifts besides $shiftx,
and the previous version did attempt to remove that final padding at the
end so that the native zero/sign/x-extension behavior of the shift cell
would be used, but since the last selectable window also got
power-of-two padding appended after the padding the code is trying to
remove got added, it did not actually fully remove it in some cases.
I changed the code to only add 'x padding between selectable windows,
leaving the last selectable window unpadded. This omits the need to add
final padding to a multiple of the constant factor in the first place.
In turn, that means the only 'x bits added are actually impossible to
select. As a side effect no padding is added when the constant factor is
equal to or larger than the width of the shift data input, also solving
the reported performance bug.
This fixes#4056
Remove duplicate %.pmg -> %_pm.h pattern. One of the duplicates overrode
the other, and in some conditions there were build races as to whether
the target directory for the generated header would exist. Instead have
a single rule which is properly generalized.
More consistent indentation and section headings.
Convert yoscrypt blocks to lists of cmdrefs (so they link to the commands in question).
Also update said lists.
Add other common optimizations/mapping commands.
Remove example synth script in favour of the examples on the next page.
Renamed python script so that it sits next to the testbench file when alphabetically sorted.
Reverted `MAX_WIDTH` to full precision for truncation testing.
Expected values are now stored in full precision rather than truncating to the same value as the input.
i.e. 0x5a5a5a5a will truncate to 0x5a5a for write data but will remain 0x5a5a5a5a for expected read.
Adds TDP submodule to generator.
Adds shorthand expected signal to testbench (mostly to make it easier when I look at the vcd dump to figure out what I did wrong in tests).