Accepts '?' in Case, maps to '-'

[nmigen-issue-migration]

Issue by RobertBaruch
Wednesday Sep 11, 2019 at 05:04 GMT
Originally opened as m-labs/nmigen#203

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- is the don't-care value in IL, but ? is the don't-care value in Verilog. This change allows you to use both in a Case.

Tested:

• Added test case
• Tested using this example, generating via -t il and -t v and inspecting output is well-formed:

from nmigen import *
from nmigen.cli import main
from nmigen.asserts import *


class TestCase(Elaboratable):
    def __init__(self):
        self.input = Signal(8)
        self.output = Signal()

    def elaborate(self, platform):
        m = Module()

        with m.Switch(self.input):
            with m.Case(0b00000000):
                m.d.comb += self.output.eq(1)
            with m.Case("1???0000"):
                m.d.comb += self.output.eq(0)
            with m.Default():
                m.d.comb += self.output.eq(1)
        return m


if __name__ == "__main__":
    clk = Signal()
    rst = Signal()

    pos = ClockDomain()
    pos.clk = clk
    pos.rst = rst

    testcase = TestCase()

    m = Module()
    m.domains.pos = pos
    m.submodules.testcase = testcase

    main(
        m,
        ports=[clk, rst, testcase.input, testcase.output],
        platform="formal")

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RobertBaruch included the following code: https://github.com/m-labs/nmigen/pull/203/commits

[nmigen-issue-migration]

Comment by codecov[bot]
Wednesday Sep 11, 2019 at 05:17 GMT

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Codecov Report

Merging #203 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #203      +/-   ##
==========================================
+ Coverage   82.84%   82.85%   +<.01%     
==========================================
  Files          33       33              
  Lines        5294     5296       +2     
  Branches     1136     1137       +1     
==========================================
+ Hits         4386     4388       +2     
  Misses        783      783              
  Partials      125      125

Impacted Files	Coverage Δ
nmigen/hdl/dsl.py	99.69% <100%> (ø)	⬆️

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