http://vr-zone.com/articles/amd-push...ses/17088.html
Take with a pinch of salt as Barcelona was hyped up before release as was bulldozer.

However I'll draw you to the following paragraph:
Quote Originally Posted by AMD engineer
"Steamroller is not Bulldozer Enhanced. F*** no. The layout might look the same but our LEGO blocks are completely different. When all is said and done we should get 45% improvement and this goes to show how the Bulldozer was f***** design. This is all what Bulldozer was supposed to be."
Haswell's been indicated to be around 10% faster than Ivy Bridge. Steamroller may just be close enough to Intel's top end that the difference is irrelevant.

Oh and Bulldozer's ****. I told you so before it was even released.