Stock index futures were higher on Wednesday as Wall Street looked to build on gains in the previous session after unofficial data showed Chinese exports blew past expectations, easing concerns about a global recovery.

Chinese exports jumped about 50 percent in May from a year earlier, sources told Reuters. If the data is officially confirmed on Thursday, the surge would suggest the risk of a Chinese economic downturn is very small. The report fueled a rise in stock markets globally.

On Tuesday, U.S. stocks mostly rose on strength in materials and financial shares. Late-day volatility led to equities closing at or near session highs after a wobbly session.

Investors have been looking for signs that Wall Street will reverse a slide that has pushed the S&P 500 into correction territory -- a decline of more than 10 percent from its April 23 high.

Definitely, there has been a search for a bottom for this recent freefall and yesterday's stock action was very encouraging in that regard, particularly the final push at the end of the day, said Rick Meckler, president of investment firm LibertyView Capital Management in New York.

You got a very, very strong finish which easily could have been a continued rout of stock prices. So whenever you get that, it's like sticking your toe back in the water.

S&P 500 futures rose 6.3 points and were slightly above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures gained 51 points, and Nasdaq 100 futures rose 9 points.

Texas Instruments Inc will be in focus after the chipmaker said second-quarter earnings and revenue would be at the high end of its forecast on strong broad-based demand for its chips, particularly from industrial customers.

Technology companies have a large sales base in Europe, and their shares have been under pressure recently as investors questioned how the euro-zone debt crisis will affect profits.

U.S. healthcare software company Allscripts Misys Healthcare Solutions Inc said Wednesday it will buy rival Eclipsys Corp in a $1.3 billion all-stock deal that could create a market leader in electronic healthcare records.

Banco Santander said it will pay $2.5 billion for the 24.9 percent of Santander Mexico it does not own, showing that the Spanish bank's expansion ambitions have not been slowed by a raft of purchases in the past 18 months.

Sprint Nextel Corp said Tuesday it inadvertently overstated launch-day sales of the much-anticipated EVO 4G phone from HTC Corp <2498.TW>, touted as a serious competitor to Apple Inc's iPhone 4.

Federal Reserve Chairman Ben Bernanke will testify before the U.S. House Budget Committee at 10 a.m. EDT (1400 GMT). The Fed's Beige Book survey of economic activity will be released at 2 p.m. EDT (1800 GMT)

European shares rose 1 percent at midday on Wednesday after the report on Chinese export data, while concerns over BP's dividend were a drag on the market.

(Reporting by Chuck Mikolajczak; editing by Jeffrey Benkoe)