No, no, no Computer Science would be destroyed, not Mathematics.
A large portion of Computer Science is the study of algorithms including their complexity.
How can you say something is going to be destroyed by something that isn't even a question in the field?
If anything Mathematics is going to be improved by getting rid of some grunt work and giving way for some more creativity. Not to mention the theorems that if P=NP would come about which could be used for even further results.
Mathematics and computer science are intertwined. And they would not be destroyed --- but merely closed (to a large extent) as a solved problem.
Algorithms and proofs have many interconnections. (You can usually abstract one out of the other with a bit of creativity. I.e. the classic proof for infinity of primes gives a basic algorithm for creating new primes.)
A large portion of Computer Science is the study of algorithms including their complexity.
How can you say something is going to be destroyed by something that isn't even a question in the field?
If anything Mathematics is going to be improved by getting rid of some grunt work and giving way for some more creativity. Not to mention the theorems that if P=NP would come about which could be used for even further results.
All-in-all it's a win-win for Mathematics.