NEW YORK (MarketWatch) — These are stocks making notable moves on Tuesday:

Gainers:

Compuware Corp. CPWR, +13.37% : The technology performance companyagreed to be acquired by private-equity firm Thoma Bravo.

Trina Solar Ltd. TSL, +5.03% : The solar-panel maker will build and own one of China’s largest solar-power projects.

Apple Inc. AAPL, +0.71% : Buzz builds around a Sept. 9 event at which the highly anticipated iPhone 6 and possibly the iWatch could be unveiled, sending shares to yet another intraday record. Resale sites have reported a surge in trade-ins of old iPhones.

Tesla Motors Inc. TSLA, +5.12% : An analyst who covers the electric-vehicle manufacturer sets a $400 price target. Shares hit an intraday record.

Twitter Inc. TWTR, +2.50% : The social-networking company opened above $50 for the first time since March.

Norwegian Cruise Line Holdings Ltd. NCLH, +11.02% : The cruise line agreed to buy Prestige Cruises International, which is owned by private-equity firm Apollo Global Management LLC.

iDreamSky Technology Ltd. DSKY, +3.96% : The mobile game distributor’s IPO “quiet period” has expired and the upbeat analyst notes are following.

Groupon Inc. GRPN, +3.37% : The online deals site was upgraded to sector perform from underperform by RBC.

Dollar General Corp. DG, +0.48% : The dollar-store chain raised its offer for rival Family Dollar Stores Inc. FDO, +0.49%

Decliners:

Conn’s Inc. CONN, -30.69% : The furniture and appliance retailer missed fiscal second-quarter profit forecast and slashed its full-year outlook.

Exelixis Inc. EXEL, -54.13% : The biotech company late Monday said a clinical trial failed to meet its goal and that it would cut its workforce by about 70%.

Home Depot Inc. HD, -1.96% : The improvement company is investigating a potential customer credit or debit card breach.

Tickers to watch:

Under Armour Inc. UA, +3.48% : Nike Inc. NKE, +0.76%  is matching Under Armour’s giant endorsement offer to Oklahoma City Thunder forward Kevin Durant that would keep the NBA star part of Team Swoosh for years to come.

Toyota Motor Corp. TM, +1.56% : The Japanese car manufacturer is set to introduce a hydrogen-cell car for the masses.

Duke Energy Corp. DUK, -0.80% : The energy giant is the co-owner of a new natural-gas line that will run from West Virginia to North Carolina.

Halliburton Co. HAL, -0.35% : The oil-and-gas exploration company settles claims from the 2010 Deepwater Horizon rig explosion in the Gulf of Mexico.