US STOCKS-Wall Street ends stronger after volatile session
* S&P 500 ends higher after early decline
* U.S. oil prices reverse losses
* China slowdown fears have dragged commodities towards 2015 lows
* AMD revenue warning weighs on semiconductor companies
* Indexes end higher: Dow 0.53 pct, S&P 0.61 pct, Nasdaq 0.11 pct (Adds detail on Reuters oil stocks poll)
By Noel Randewich
July 7 (Reuters) - U.S. stocks ended higher after a choppy session on Tuesday, as a rebound in U.S. oil prices helped offset concerns about a slowdown in China and the Greek debt crisis.
The S&P energy index reversed course to trade up 0.9 percent as U.S. crude oil rose 0.7 percent after trading as much as 3.7 percent lower earlier in the day.
U.S. commercial crude oil stocks likely slipped in the week ended July 3 after rising for the first time since April in the previous week, an expanded Reuters survey showed on Tuesday. Continuación...