Don't build Shiv if you want attack speed. Bork, IE, Tri-Force, PD (situational), LW, Sorc Shoes. Shiv is generally not that great on Corki since he spams spells as much as aa. Bloodthirster is really good if you are super ahead or need more damage. I do need to know runes because I'm not sure your ADC page and if you don't run Attack Speed quints, the Shiv is actually really good for you.
I haven't played a good Ahri game in a long time
Darb Pl0x