A consolidation or split has no tax consequences and there no need to do or report anything. Take LYC which recently consolidated 10:1. Your ten shares are now 1 share and the price you paid for the 10 shares is now the purchase price you are deemed to have paid for the 1 share you now hold. If you bought for 10 shares for 10c (total outlay $1) then after consolidation you now have 1 share worth $1 and hopefully the share price will now be 10 times what it was before the consolidation. When you finally sell your shares you just calculate the profit (hopefully) based on the new cost price of $1 in my example.
