In short, the GOP is expected to offer two sticks and two carrots. Each of them would change the industry's way of doing things for the past several decades.

1. Change the treatment of carried interest from capital gains to ordinary income.

This is the one that most private equity executives have been dreading since Barack Obama first walked into the White House, but which was a victim of bipartisan inaction on corporate tax reform. In short, it means private equity executives would pay higher taxes on investment profits. Today it would be the difference between 39.6% and 20% at the federal level, although the specifics are likely to change as Republicans are promising lower individual rates. It would not affect the vast majority of private equity profits, which are earned by third-party investors ― including many tax-exempt organizations like university endowments, public pensions and charitable foundations. It's also worth noting that while this was a standard part of Trump's stump speech, Ryan has not yet publicly embraced it.

2. Eliminate corporate interest deductions

A key driver for private equity returns isn't equity at all, but rather is debt. Here's how it works: A private equity finances the majority of an acquisition by soliciting bank loans, all of which are put onto the books of the purchased company. The company then gets to deduct 100% of the interest on those loans. There have been past efforts to eat into this tax break ― since it incentivizes debt over equity ― but not even those were bold enough to propose an entire elimination. Expect private equity to howl.

3. Lower the corporate tax rate

Today's corporate tax rate is around 35%, which applies only to earnings (minus deductions, which makes most effective corporate tax rates much lower). Paul Ryan wants the top-line figure cut to 20%, while Donald Trump wants it at 15%. Either way, it would be a boon for profitable companies in private equity portfolios, and could take some of the sting out of this list's first two items (or perhaps become a net positive, depending on how highly a company is leveraged).

4. Full CapEx expensing

Companies would get full tax write-offs on capital expenditures, such as equipment purchases or facilities improvements, within the year of expense. The current system requires depreciation over time. If you're a private equity firm that wants to buy a company, pump in working capital and flip it within a few years, then an immediate write-off would make the exit more appealing.