fhdl/tools: clock domain merging for clock renaming

diff --git a/migen/fhdl/tools.py b/migen/fhdl/tools.py
index 7e934c905ce4cb5a913f6a17062bdc0cc1970512..447333668f2e179aa5728382b603eef374bf560d 100644 (file)
--- a/migen/fhdl/tools.py
+++ b/migen/fhdl/tools.py
@@ -224,7 +224,10 @@ def rename_clock_domain_expr(f, old, new):
 
 def rename_clock_domain(f, old, new):
        rename_clock_domain_expr(f, old, new)
-       f.sync[new] = f.sync[old]
+       if new in f.sync:
+               f.sync[new].extend(f.sync[old])
+       else:
+               f.sync[new] = f.sync[old]
        del f.sync[old]
        for special in f.specials:
                special.rename_clock_domain(old, new)