I mean, there were warning signs before June 4th. Those who left before probably survived. As for those who stayed, and if they managed to survive that day, they would probably be identified and arrested, but some managed to escape to then UK-controlled Hong Kong.

See: https://en.wikipedia.org/wiki/Operation_Yellowbird

Yellowbird successfully helped more than 400 dissidents, who were smuggled through Hong Kong, and then onwards to Western countries. Notable escapees include Wu’erkaixi, Chai Ling, Li Lu, Feng Congde, Chen Yizi, and Su Xiaokang. Three Hong Kong–based activists were arrested by the Chinese authorities, but later released after the intervention of the Hong Kong government.

As for the rest: https://en.wikipedia.org/wiki/1989_Tiananmen_Square_protests_and_massacre#Arrests,_punishments,_and_evacuations

The 21 most-wanted student leaders’ faces and descriptions were often broadcast on television. Photographs with biographies of the leaders followed in this order: Wang Dan, Wuer Kaixi, Liu Gang, Chai Ling, Zhou Fengsuo, Zhai Weimin, Liang Qingdun, Wang Zhengyun, Zheng Xuguang, Ma Shaofang, Yang Tao, Wang Zhixing, Feng Congde, Wang Chaohua, Wang Youcai, Zhang Zhiqing, Zhang Boli, Li Lu, Zhang Ming, Xiong Wei, and Xiong Yan.

Each of the 21 students faced diverse experiences after their arrests or escapes; while some remain abroad with no intent to return, others have chosen to stay indefinitely, such as Zhang Ming. Only 7 of the 21 were able to escape. Some student leaders, such as Chai Ling and Wuer Kaixi, were able to escape to the United States, the United Kingdom, France, and other Western nations

The remaining student leaders were apprehended and incarcerated. Those who escaped, whether in 1989 or after, generally have had difficulty re-entering China up to this day. The Chinese government has preferred to leave the dissidents in exile. Those who attempt to re-enter, such as Wu’er Kaixi, have been simply sent back but not arrested.

Chen Ziming and Wang Juntao were arrested in late 1989 for their involvement in the protests. Chinese authorities alleged they were the “black hands” behind the movement. Both Chen and Wang rejected the allegations made against them. They were put on trial in 1990 and sentenced to 13 years in prison. Others, such as Zhang Zhiqing, have essentially disappeared. After his initial arrest in January 1991 and subsequent release, nothing further is known about his situation and where he lives now. Zhang Zhiqing’s role and reason for being listed on the 21 most wanted is generally unknown; this is the case for many others on the list, such as Wang Chaohua.

According to the Dui Hua Foundation, citing a provincial government, 1,602 individuals were imprisoned for protest-related activities in early 1989. As of May 2012, at least two remain incarcerated in Beijing, and five others remain unaccounted for. In June 2014, it was reported that Miao Deshun was believed to be the last known prisoner incarcerated for their participation in the protests; he was last heard from a decade ago.

Also, some of the leadership got purged:

The party leadership expelled Zhao Ziyang from the Politburo Standing Committee (PSC). Hu Qili, another PSC member who opposed martial law but abstained from voting, was also removed from the committee.

As bad as it may sound, remember that, during Imperial China, they would all just lose their head, like the Emperor would literally order your head to be cut off. It could’ve been much worse.

Removed by mod