My boss never wanted to hire me, overworks me and I have no upside at my current firm. How do I extract myself out of here?

Having issues at my current job, I am vastly underpaid relative to peers and despite strong performance, I'm not being given the opportunity to expand my coverage or get more responsibility.

This is my second job, I was very excited to be on the buy-side after a grueling 5 years in banking. However, I always felt that my current boss was overworking me and just not giving me the best opportunity to shine (my coverage universe is crap, and I have outperformed massively) . This has been going on for 2 years. I happened to sit down with one of the senior guys at the fund, who basically told me that my boss didn't want to hire a junior but higher-ups wanted him to hire me to create a deeper bench. It all finally clicked, why he acts this way, why he overworks me for NO reason whatsoever and then whines about how my names aren't working (they have massively outperformed against my coverage, my sector just has been dead money for 2 years). Every day, he gives me something new to work on and doesn't give me any time to complete them. He doesn't want me around, potentially views me as someone who will / can replace him.

I am a bit lost now, how do I get myself out of this situation (esp because he is hell bent on just working me into the ground)?