amaranth/nmigen/back/verilog.py
whitequark 868d49eccd back.verilog: refactor Yosys script generation. NFCI.
In commit 5f30bcbb, back.cxxsim gained a nicer way to generate
a script; this commit brings it to back.verilog too.
2020-06-14 09:38:32 +00:00

53 lines
2 KiB
Python

from .._yosys import *
from . import rtlil
__all__ = ["YosysError", "convert", "convert_fragment"]
def _convert_rtlil_text(rtlil_text, *, strip_internal_attrs=False, write_verilog_opts=()):
# this version requirement needs to be synchronized with the one in setup.py!
yosys = find_yosys(lambda ver: ver >= (0, 9))
yosys_version = yosys.version()
script = []
script.append("read_ilang <<rtlil\n{}\nrtlil".format(rtlil_text))
if yosys_version >= (0, 9, 231):
# Yosys 0.9 release has buggy proc_prune.
script.append("delete w:$verilog_initial_trigger")
script.append("proc_prune")
script.append("proc_init")
script.append("proc_arst")
script.append("proc_dff")
script.append("proc_clean")
script.append("memory_collect")
if strip_internal_attrs:
attr_map = []
attr_map.append("-remove generator")
attr_map.append("-remove top")
attr_map.append("-remove src")
attr_map.append("-remove nmigen.hierarchy")
attr_map.append("-remove nmigen.decoding")
script.append("attrmap {}".format(" ".join(attr_map)))
script.append("attrmap -modattr {}".format(" ".join(attr_map)))
script.append("write_verilog -norename {}".format(" ".join(write_verilog_opts)))
return yosys.run(["-q", "-"], "\n".join(script),
# At the moment, Yosys always shows a warning indicating that not all processes can be
# translated to Verilog. We carefully emit only the processes that *can* be translated, and
# squash this warning. Once Yosys' write_verilog pass is fixed, we should remove this.
ignore_warnings=True)
def convert_fragment(*args, strip_internal_attrs=False, **kwargs):
rtlil_text, name_map = rtlil.convert_fragment(*args, **kwargs)
return _convert_rtlil_text(rtlil_text, strip_internal_attrs=strip_internal_attrs), name_map
def convert(*args, strip_internal_attrs=False, **kwargs):
rtlil_text = rtlil.convert(*args, **kwargs)
return _convert_rtlil_text(rtlil_text, strip_internal_attrs=strip_internal_attrs)