From 11b1e532248579791b1c0a0f682e3d4d20ba545b Mon Sep 17 00:00:00 2001 From: Sebastien Bourdeauducq Date: Wed, 28 Nov 2012 17:50:55 +0100 Subject: [PATCH] visit/NodeTransformer: copy most nodes --- migen/fhdl/visit.py | 52 +++++++++++++++++++++++---------------------- 1 file changed, 27 insertions(+), 25 deletions(-) diff --git a/migen/fhdl/visit.py b/migen/fhdl/visit.py index 81ca275b8..595f40052 100644 --- a/migen/fhdl/visit.py +++ b/migen/fhdl/visit.py @@ -1,3 +1,5 @@ +from copy import copy + from migen.fhdl.structure import * from migen.fhdl.structure import _Operator, _Slice, _Assign, _ArrayProxy @@ -87,6 +89,12 @@ class NodeVisitor: def visit_unknown(self, node): pass +# Default methods always copy the node, except for: +# - Constants +# - Signals +# - Unknown objects +# - All fragment fields except comb and sync +# In those cases, the original node is returned unchanged. class NodeTransformer: def visit(self, node): if isinstance(node, Constant): @@ -127,42 +135,37 @@ class NodeTransformer: return node def visit_Operator(self, node): - node.operands = [self.visit(o) for o in node.operands] - return node + return _Operator(node.op, [self.visit(o) for o in node.operands]) def visit_Slice(self, node): - node.value = self.visit(node.value) - return node + return _Slice(self.visit(node.value), node.start, node.stop) def visit_Cat(self, node): - node.l = [self.visit(e) for e in node.l] - return node + return Cat(*[self.visit(e) for e in node.l]) def visit_Replicate(self, node): - node.v = self.visit(node.v) - return node + return Replicate(self.visit(node.v), node.n) def visit_Assign(self, node): - node.l = self.visit(node.l) - node.r = self.visit(node.r) - return node + return _Assign(self.visit(node.l), self.visit(node.r)) def visit_If(self, node): - node.cond = self.visit(node.cond) - node.t = self.visit(node.t) - node.f = self.visit(node.f) - return node + r = If(self.visit(node.cond)) + r.t = self.visit(node.t) + r.f = self.visit(node.f) + return r def visit_Case(self, node): - node.test = self.visit(node.test) - node.cases = [(v, self.visit(statements)) for v, statements in node.cases] - node.default = self.visit(node.default) - return node + r = Case(self.visit(node.test)) + r.cases = [(v, self.visit(statements)) for v, statements in node.cases] + r.default = self.visit(node.default) + return r def visit_Fragment(self, node): - node.comb = self.visit(node.comb) - node.sync = self.visit(node.sync) - return node + r = copy(node) + r.comb = self.visit(node.comb) + r.sync = self.visit(node.sync) + return r def visit_statements(self, node): return [self.visit(statement) for statement in node] @@ -171,9 +174,8 @@ class NodeTransformer: return dict((clockname, self.visit(statements)) for clockname, statements in node.items()) def visit_ArrayProxy(self, node): - node.choices = [self.visit(choice) for choice in node.choices] - node.key = self.visit(node.key) - return node + return _ArrayProxy([self.visit(choice) for choice in node.choices], + self.visit(node.key)) def visit_unknown(self, node): return node