nmigen/back/verilog.py

   1 from .._toolchain.yosys import *
   2 from . import rtlil
   3
   4
   5 __all__ = ["YosysError", "convert", "convert_fragment"]
   6
   7
   8 def _convert_rtlil_text(rtlil_text, *, strip_internal_attrs=False, write_verilog_opts=()):
   9     # this version requirement needs to be synchronized with the one in setup.py!
  10     yosys = find_yosys(lambda ver: ver >= (0, 9))
  11     yosys_version = yosys.version()
  12
  13     script = []
  14     script.append("read_ilang <<rtlil\n{}\nrtlil".format(rtlil_text))
  15
  16     if yosys_version >= (0, 9, 3468):
  17         # Yosys >=0.9+3468 (since commit f3d7e9a1) emits Verilog without a possible sim/synth
  18         # mismatch, making $verilog_initial_trigger unnecessary.
  19         script.append("delete w:$verilog_initial_trigger")
  20         script.append("proc_prune")
  21     script.append("proc_init")
  22     script.append("proc_arst")
  23     script.append("proc_dff")
  24     script.append("proc_clean")
  25     script.append("memory_collect")
  26
  27     if strip_internal_attrs:
  28         attr_map = []
  29         attr_map.append("-remove generator")
  30         attr_map.append("-remove top")
  31         attr_map.append("-remove src")
  32         attr_map.append("-remove nmigen.hierarchy")
  33         attr_map.append("-remove nmigen.decoding")
  34         script.append("attrmap {}".format(" ".join(attr_map)))
  35         script.append("attrmap -modattr {}".format(" ".join(attr_map)))
  36
  37     script.append("write_verilog -norename {}".format(" ".join(write_verilog_opts)))
  38
  39     return yosys.run(["-q", "-"], "\n".join(script),
  40         # At the moment, Yosys always shows a warning indicating that not all processes can be
  41         # translated to Verilog. We carefully emit only the processes that *can* be translated, and
  42         # squash this warning. Once Yosys' write_verilog pass is fixed, we should remove this.
  43         ignore_warnings=True)
  44
  45
  46 def convert_fragment(*args, strip_internal_attrs=False, **kwargs):
  47     rtlil_text, name_map = rtlil.convert_fragment(*args, **kwargs)
  48     return _convert_rtlil_text(rtlil_text, strip_internal_attrs=strip_internal_attrs), name_map
  49
  50
  51 def convert(*args, strip_internal_attrs=False, **kwargs):
  52     rtlil_text = rtlil.convert(*args, **kwargs)
  53     return _convert_rtlil_text(rtlil_text, strip_internal_attrs=strip_internal_attrs)