riscv-formal-nmigen/nmigen/tracer.py

56 lines
1.6 KiB
Python

import sys
from opcode import opname
__all__ = ["NameNotFound", "get_var_name", "get_src_loc"]
class NameNotFound(Exception):
pass
_raise_exception = object()
def get_var_name(depth=2, default=_raise_exception):
frame = sys._getframe(depth)
code = frame.f_code
call_index = frame.f_lasti
while True:
call_opc = opname[code.co_code[call_index]]
if call_opc in ("EXTENDED_ARG",):
call_index += 2
else:
break
if call_opc not in ("CALL_FUNCTION", "CALL_FUNCTION_KW", "CALL_FUNCTION_EX", "CALL_METHOD"):
return None
index = call_index + 2
while True:
opc = opname[code.co_code[index]]
if opc in ("STORE_NAME", "STORE_ATTR"):
name_index = int(code.co_code[index + 1])
return code.co_names[name_index]
elif opc == "STORE_FAST":
name_index = int(code.co_code[index + 1])
return code.co_varnames[name_index]
elif opc == "STORE_DEREF":
name_index = int(code.co_code[index + 1])
return code.co_cellvars[name_index]
elif opc in ("LOAD_GLOBAL", "LOAD_ATTR", "LOAD_FAST", "LOAD_DEREF",
"DUP_TOP", "BUILD_LIST"):
index += 2
else:
if default is _raise_exception:
raise NameNotFound
else:
return default
def get_src_loc(src_loc_at=0):
# n-th frame: get_src_loc()
# n-1th frame: caller of get_src_loc() (usually constructor)
# n-2th frame: caller of caller (usually user code)
frame = sys._getframe(2 + src_loc_at)
return (frame.f_code.co_filename, frame.f_lineno)