I need help identifying this plant

[BMagyar69]

I have had it several years and it grows everywhere. it spreads thru roots; dies back in the winter; has yellow flowers in the summer. Grows like a bush, but the stems are not woody. It started out verigated, but also has come up just dark green. Any one know this plant? It looks like a weigla, but it isn't.

[GreenGrower]

A picture is worth 1000 words.

[Guest]

Sorry I can not suggest a name for this plant