[llvm] [DTLTO] [LLVM] Initial DTLTO cache implementation (PR #156433)

[Katya Romanova via llvm-commits]

romanova-ekaterina wrote:

> Sorry for the slow review. Comments below.
> 
> Please also add llvm-lto2 based tests to llvm/test/ThinLTO/X86/dtlto, so that this gets exercised by LLVM tests.

Sorry for the delayed response too. Your review came on the day I had a surgery. After that I was on short time leave from work for a month. Just returned back to work.

https://github.com/llvm/llvm-project/pull/156433