[clang] [Serialization] Load Specializations Lazily (PR #76774)

[Chuanqi Xu via cfe-commits]

ChuanqiXu9 wrote:

> This patch does too many things for me to be able to review it. This patch fails on our infrastructure.
> 
> I'd propose to simplify it to basically D41416 + the on-disk hash table. We should read all of the entries upon module loading to simplify the logic in reading the hashes lazily. Reading the hashes lazily could be done but I doubt its worth the complexity of the implementation at that stage.

It is surprising to me since the HashTable shouldn't be generated at all: https://github.com/llvm/llvm-project/pull/76774/files#diff-6fe53759e8d797c328c73ada5f3324c6248a8634ef36131c7eb2b9d89192bb64R4073-R4079

The suggestion to proceed sounds good to me  but it may take some time.

https://github.com/llvm/llvm-project/pull/76774