Check out the companies making headlines in midday trading Tuesday.

PagSeguro — Shares popped 4.1% on Tuesday after Citi upgraded the Brazilian payment stock to buy from neutral. The firm called the company's fourth-quarter earnings unsurprising and said it is still in rough waters, but shares were more attractive following recent underperformance. Stone, which was also upgraded by Citi to buy from neutral, edged higher as well on Tuesday.

Affirm — The pay-later service lost 7.3% after Apple announced a competing service. Apple shares were down about 0.9%.

Occidental Petroleum — The energy stock jumped 4.3% on Tuesday after a regulatory filing showed Warren Buffett's Berkshire Hathaway purchased an additional 3.7 million shares for $216 million on Monday and last Thursday. TD Cowen upgraded Occidental to outperform from market perform following the news.

Micron Technology — The semiconductor stock dropped 0.85% ahead of its scheduled second-quarter earnings report after the bell on Tuesday. Analysts expect revenue of $3.71 billion and a loss per share of 67 cents, according to FactSet. Micron's shares have gained more than 18.5% in the last six months. 

PVH — Shares soared 20% after the apparel company's fourth-quarter adjusted earnings per share came in at $2.38, beating estimates of $1.67, per Refinitiv. Its revenue of $2.49 billion beat expectations of $2.37 billion. PVH's guidance for the first quarter and full year also surpassed estimates.

Paramount — Shares of the media giant gained 3.1% during Tuesday's trading session on a rating upgrade from Bank of America from neutral to buy. The bank highlighted Paramount's strong lineup of assets that could help the business in the event it puts itself up for sale.

McCormick & Company — The spice maker's stock price jumped 9.6% after reporting better-than-expected earnings for the first quarter. McCormick reported quarterly earnings of 59 cents per share, while analysts surveyed by FactSet expected 50 cents per share. 

Alibaba — Shares soared by nearly 14.3% after the e-commerce giant said it would split its company into six separate business groups, with each group having the potential to raise outside funding and go public.

Ciena — The technology company gained about 4.7% on Tuesday after Raymond James upgraded the stock to strong buy from outperform.

Walgreens Boots Alliance — Shares of the pharmacy giant rose more than 2.7% after the company reported an increase in its quarterly revenue despite seeing a sharp decline in demand for Covid tests and vaccines. Walgreens posted revenue of $34.86 billion for the most recent quarter, compared to analysts' estimates of $33.53 billion, according to Refinitiv.

Carnival Corp — The cruise operator's stock price rose 6.1% on Tuesday after Wells Fargo upgraded Carnival to equal weight from underweight. The firm said it sees a more balanced risk/reward for the company

— CNBC's Alex Harring, Yun Li, Jesse Pound and Michelle Fox Theobald contributed reporting.

Correction: According to FactSet, Micron is expected to post a loss of 67 cents per share. A previous version misstated the estimate.