From 3971600917a9179777715b1b0b160d24cf4ed48e Mon Sep 17 00:00:00 2001
From: Sebastien Bourdeauducq <sebastien@milkymist.org>
Date: Fri, 23 Nov 2012 17:20:08 +0100
Subject: [PATCH] fhdl/structure: use sets for memories and instance
 collections

---
 migen/fhdl/structure.py | 12 ++++++------
 migen/fhdl/tools.py     |  2 +-
 migen/uio/ioo.py        |  2 +-
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/migen/fhdl/structure.py b/migen/fhdl/structure.py
index 2249b466..4db0580b 100644
--- a/migen/fhdl/structure.py
+++ b/migen/fhdl/structure.py
@@ -324,8 +324,8 @@ class Fragment:
 	def __init__(self, comb=None, sync=None, instances=None, memories=None, sim=None):
 		if comb is None: comb = []
 		if sync is None: sync = dict()
-		if instances is None: instances = []
-		if memories is None: memories = []
+		if instances is None: instances = set()
+		if memories is None: memories = set()
 		if sim is None: sim = []
 		
 		if isinstance(sync, list):
@@ -333,8 +333,8 @@ class Fragment:
 		
 		self.comb = comb
 		self.sync = sync
-		self.instances = instances
-		self.memories = memories
+		self.instances = set(instances)
+		self.memories = set(memories)
 		self.sim = sim
 		
 	
@@ -345,8 +345,8 @@ class Fragment:
 		for k, v in other.sync.items():
 			newsync[k].extend(v)
 		return Fragment(self.comb + other.comb, newsync,
-			self.instances + other.instances,
-			self.memories + other.memories,
+			self.instances | other.instances,
+			self.memories | other.memories,
 			self.sim + other.sim)
 	
 	def rename_clock_domain(self, old, new):
diff --git a/migen/fhdl/tools.py b/migen/fhdl/tools.py
index 0b126921..0382892d 100644
--- a/migen/fhdl/tools.py
+++ b/migen/fhdl/tools.py
@@ -84,7 +84,7 @@ def group_by_targets(sl):
 def list_inst_ios(i, ins, outs, inouts):
 	if isinstance(i, Fragment):
 		return list_inst_ios(i.instances, ins, outs, inouts)
-	elif isinstance(i, list):
+	elif isinstance(i, set):
 		if i:
 			return set.union(*(list_inst_ios(e, ins, outs, inouts) for e in i))
 		else:
diff --git a/migen/uio/ioo.py b/migen/uio/ioo.py
index 907d85e9..c5b9263e 100644
--- a/migen/uio/ioo.py
+++ b/migen/uio/ioo.py
@@ -14,7 +14,7 @@ class UnifiedIOObject(Actor):
 		self._memories = set(v for v in self.buses.values() if isinstance(v, Memory))
 	
 	def get_fragment(self):
-		return Fragment(memories=list(self._memories))
+		return Fragment(memories=self._memories)
 
 (_WAIT_COMPLETE, _WAIT_POLL) = range(2)
 
-- 
2.30.2