Support for yosys' $anyconst and $anyseq cells

[nmigen-issue-migration]

Issue by cr1901
Tuesday Jan 15, 2019 at 22:08 GMT
Originally opened as m-labs/nmigen#25

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AnyConst and AnySeq correspond to to the $anyconst and $anyseq RTLIL cells. They are useful for formal verification to represent "any value that doesn't change", and "any value that can change to another arbitrary value each clock cycle" respectively.

Usage is analogous to declaring a Constant or Signal:

self.foo = AnyConst(2)
self.bar = AnySeq(16)

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cr1901 included the following code: https://github.com/m-labs/nmigen/pull/25/commits

[nmigen-issue-migration]

Comment by codecov[bot]
Tuesday Jan 15, 2019 at 22:23 GMT

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Codecov Report

Merging #25 into master will decrease coverage by 0.32%.
The diff coverage is 50%.

@@            Coverage Diff             @@
##           master      #25      +/-   ##
==========================================
- Coverage    80.4%   80.08%   -0.33%     
==========================================
  Files          19       19              
  Lines        2986     3018      +32     
  Branches      644      648       +4     
==========================================
+ Hits         2401     2417      +16     
- Misses        541      555      +14     
- Partials       44       46       +2

Impacted Files	Coverage Δ
nmigen/back/pysim.py	95.26% <100%> (+0.03%)	⬆️
nmigen/hdl/xfrm.py	92.38% <40%> (-1.88%)	⬇️
nmigen/hdl/ast.py	80.75% <44.44%> (-1.02%)	⬇️

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