[llvm] [BOLT][NFC] Store FILE symbols in a vector (PR #89088)

[Amir Ayupov via llvm-commits]

aaupov wrote:

> > > > For reference, in one of our medium-sized test binaries we have:
> > > 
> > > 
> > > Can we try on large binaries and try to have an upper bound on the size? I am not against this I just want to make sure we don't regress time dramatically.
> > 
> > 
> > For one large prod binary, we have the following:
> > 
> > * 2356369 local symbols,
> > * 1327085 local function symbols,
> > * 27784 file symbols.
> 
> What's the BOLT processing time before/after the change? 100MB is a significant amount but how does it compare with BOLT's peak memory usage?

It's a drop in the bucket, processing time- and peak memory- wise (~1/1000). Treat this diff as a data structure change to facilitate new use case (which will bring memory consumption back up).

https://github.com/llvm/llvm-project/pull/89088