Regression with latest magma release

[leonardt]

Steps to reproduce

❯ cd mantle
❯ git checkout master
❯ pytest --target coreir tests/test_mantle -k test_ram
/Users/lenny/miniconda3/lib/python3.7/site-packages/pep8.py:110: FutureWarning: Possible nested set at position 1
  EXTRANEOUS_WHITESPACE_REGEX = re.compile(r'[[({] | []}),;:]')
============================================================================== test session starts ==============================================================================
platform darwin -- Python 3.7.0, pytest-3.9.3, py-1.7.0, pluggy-0.8.0
rootdir: /Users/lenny/repos/mantle, inifile:
plugins: profiling-1.4.0, pep8-1.0.6, cov-2.6.0, codestyle-1.4.0
collected 155 items / 154 deselected

tests/test_mantle/test_common_ram.py F                                                                                                                                    [100%]

=================================================================================== FAILURES ====================================================================================
___________________________________________________________________________________ test_ram ____________________________________________________________________________________

    def test_ram():
        main = m.DefineCircuit("main", "rdata", m.Out(m.Bit), "CLKIN",
                               m.In(m.Clock))

        ram = mantle.RAM(4, 1)

        waddr = mantle.Counter(4, cout=False)
        wdata = mantle.Counter(1, cout=False)
        we = 1
        raddr = mantle.Counter(4, cout=False)

        ram(raddr, waddr, wdata, we, CLK=main.CLKIN)

        m.wire(ram.RDATA[0], main.rdata)
        m.EndDefine()
        if m.mantle_target == "coreir":
            output = "coreir"
        else:
            output = "verilog"
>       m.compile("build/test_common_ram", main, output)

tests/test_mantle/test_common_ram.py:25:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
../magma/magma/compile.py:135: in compile
    __compile_to_coreir(main, file_name, opts)
../magma/magma/compile.py:50: in __compile_to_coreir
    backend.compile(main)
../magma/magma/backend/coreir_.py:424: in compile
    self.compile_dependencies(defn_or_declaration)
../magma/magma/backend/coreir_.py:413: in compile_dependencies
    self.modules[key.name] = self.compile_definition(key)
../magma/magma/backend/coreir_.py:312: in compile_definition
    self.compile_definition_to_module_definition(definition, module_definition)
../magma/magma/backend/coreir_.py:266: in compile_definition_to_module_definition
    coreir_instance = self.compile_instance(instance, module_definition)
../magma/magma/backend/coreir_.py:196: in compile_instance
    module = lib.modules[name]
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <coreir.util.LazyDict object at 0x119fe2b00>, key = 'DFF_init0_has_ceTrue_has_resetFalse_has_async_resetFalse'

    def __getitem__(self, key):
        if not key in self:
>           raise KeyError("Could not find key: {}".format(key))
E           KeyError: 'Could not find key: DFF_init0_has_ceTrue_has_resetFalse_has_async_resetFalse'

../../miniconda3/lib/python3.7/site-packages/coreir/util.py:25: KeyError
=================================================================== 1 failed, 154 deselected in 4.79 seconds ====================================================================

I suspect this may related to uniquification, but I haven't had a chance to investigate yet.

[leonardt]

We had seen an error like this before when the tsortedgraph used by the instancegraph pass was not working correctly.

[leonardt]

Fixed!