Remove unroll

migen/transform/unroll.py

@@ -1,139 +0,0 @@
-from itertools import repeat
-
-from migen.fhdl.structure import *
-from migen.fhdl.structure import _Operator, _Slice, _Assign, _ArrayProxy
-from migen.fhdl.tools import list_targets
-
-# y <= y + a + b
-#
-# unroll_sync(sync, {b: [b1, b2], c: [c1, c2], y: [y1, y2]})
-#
-# ==>
-#
-# v_y1 = y2 + a1 + b1
-# v_y2 = v_y1 + a2 + b2
-# y1 <= v_y1
-# y2 <= v_y2
-
-(_UNDETERMINED, _IN, _OUT) = range(3)
-
-# TODO: arrays
-
-def _replace_if_in(d, s):
-	try:
-		return d[s]
-	except KeyError:
-		return s
-
-def _replace(node, rin, rout, mode=_UNDETERMINED):
-	if isinstance(node, Constant):
-		return node
-	elif isinstance(node, Signal):
-		if mode == _IN:
-			return _replace_if_in(rin, node)
-		elif mode == _OUT:
-			return _replace_if_in(rout, node)
-		else:
-			raise ValueError
-	elif isinstance(node, _Operator):
-		rop = [_replace(op, rin, rout, mode) for op in node.operands]
-		return _Operator(node.op, rop)
-	elif isinstance(node, _Slice):
-		return _Slice(_replace(node.value, rin, rout, mode), node.start, node.stop)
-	elif isinstance(node, Cat):
-		rcomp = [_replace(comp, rin, rout, mode) for comp in node.l]
-		return Cat(*rcomp)
-	elif isinstance(node, Replicate):
-		return Replicate(_replace(node.v, rin, rout, mode), node.n)
-	elif isinstance(node, _Assign):
-		return _Assign(_replace(node.l, rin, rout, _OUT), _replace(node.r, rin, rout, _IN))
-	elif isinstance(node, list):
-		return [_replace(s, rin, rout) for s in node]
-	elif isinstance(node, If):
-		r = If(_replace(node.cond, rin, rout, _IN))
-		r.t = _replace(node.t, rin, rout)
-		r.f = _replace(node.f, rin, rout)
-		return r
-	elif isinstance(node, Case):
-		r = Case(_replace(case.test, rin, rout, _IN))
-		r.cases = [(c[0], _replace(c[1], rin, rout)) for c in node.cases]
-		r.default = _replace(node.default, rin, rout)
-		return r
-	else:
-		raise TypeError
-
-def _list_step_dicts(d):
-	assert(d)
-	iterdict = dict((k, iter(v)) for k, v in d.items())
-	r = []
-	try:
-		while True:
-			r.append(dict([(k, next(i)) for k, i in iterdict.items()]))
-	except StopIteration:
-		pass
-	return r
-
-def _classify_repl(statements, replacements):
-	targets = list_targets(statements)
-	inputs = {}
-	outputs = {}
-	for k, v in replacements.items():
-		if k in targets:
-			outputs[k] = v
-		else:
-			inputs[k] = v
-	return inputs, outputs
-
-def _variable_for(s, n):
-	sn = s.backtrace[-1][0]
-	if isinstance(sn, str):
-		name = "v" + str(n) + "_" + sn
-	else:
-		name = "v"
-	return Signal(s.bv, name=name, variable=True)
-
-def unroll_sync(statements, replacements):
-	if isinstance(statements, list):
-		sl = statements
-	else:
-		sl = statements(0)
-	inputs, outputs = _classify_repl(sl, replacements)
-	assert(inputs or outputs)
-	if inputs:
-		sd_in = _list_step_dicts(inputs)
-	else:
-		sd_in = repeat({})
-	if outputs:
-		sd_out = _list_step_dicts(outputs)
-		io_var_dict = sd_out[-1].copy()
-	else:
-		sd_out = repeat({})
-		io_var_dict = {}
-
-	r = []
-	for n, (di, do) in enumerate(zip(sd_in, sd_out)):
-		do_var = dict((k, _variable_for(v, n)) for k, v in do.items())
-		
-		# initialize variables
-		for k, v in io_var_dict.items():
-			if k.variable:
-				r.append(do_var[k].eq(io_var_dict[k]))
-				io_var_dict[k] = do_var[k]
-			
-		
-		# replace signals with intermediate variables and copy statements
-		io_var_dict.update(di)
-		if n: # done for n = 0 at the beginning of function
-			if isinstance(statements, list):
-				sl = statements
-			else:
-				sl = statements(n)
-		r += _replace(sl, io_var_dict, do_var)
-		
-		# assign to output signals
-		r += [v.eq(do_var[k]) for k, v in do.items()]
-		
-		# prepare the next i+o dictionary
-		io_var_dict = do_var.copy()
-	
-	return r