From 1cabcb3c3fce5c7bd0baa2c6b9075c1b35124892 Mon Sep 17 00:00:00 2001
From: Sebastien Bourdeauducq <sebastien@milkymist.org>
Date: Sat, 17 Nov 2012 19:59:22 +0100
Subject: [PATCH] uio: support generator trampolining in simulation

---
 migen/uio/ioo.py        |  3 ++-
 migen/uio/trampoline.py | 23 +++++++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 migen/uio/trampoline.py

diff --git a/migen/uio/ioo.py b/migen/uio/ioo.py
index 72dbb391e..c95c60ceb 100644
--- a/migen/uio/ioo.py
+++ b/migen/uio/ioo.py
@@ -1,6 +1,7 @@
 from migen.fhdl.structure import *
 from migen.flow.actor import *
 from migen.bus import wishbone
+from migen.uio.trampoline import Trampoline
 
 class UnifiedIOObject(Actor):
 	def __init__(self, dataflow=None, buses={}):
@@ -12,7 +13,7 @@ class UnifiedIOObject(Actor):
 
 class UnifiedIOSimulation(UnifiedIOObject):
 	def __init__(self, generator, dataflow=None, buses={}):
-		self.generator = generator
+		self.generator = Trampoline(generator)
 		super().__init__(dataflow, buses)
 		
 		self.callers = []
diff --git a/migen/uio/trampoline.py b/migen/uio/trampoline.py
new file mode 100644
index 000000000..912427de2
--- /dev/null
+++ b/migen/uio/trampoline.py
@@ -0,0 +1,23 @@
+import types
+
+class Trampoline:
+	def __init__(self, g):
+		self.stack = [g]
+	
+	def __iter__(self):
+		return self
+	
+	def __next__(self):
+		while True:
+			while True:
+				try:
+					r = next(self.stack[-1])
+					break
+				except StopIteration:
+					self.stack.pop()
+					if not self.stack:
+						raise
+			if isinstance(r, types.GeneratorType):
+				self.stack.append(r)
+			else:
+				return r