core/semantic_metadata: Support multi-version semantic metadata
The implementation had been assuming that each module will only call the
__sanitizermetadata*_{add,del} constructors and destructors once.
To support multi-version semantic metadata, we have to loosen this assumption,
as different versions of semantic metadata will end up in separate sections
with distinct constructor and destructor calls. In particular, combining TUs
with different code models will always result in different versions of semantic
metadata that need to be parsed separately.
core/semantic_metadata: Support multi-version semantic metadata
The implementation had been assuming that each module will only call the __sanitizermetadata*_{add,del} constructors and destructors once.
To support multi-version semantic metadata, we have to loosen this assumption, as different versions of semantic metadata will end up in separate sections with distinct constructor and destructor calls. In particular, combining TUs with different code models will always result in different versions of semantic metadata that need to be parsed separately.
Multi-version semantic metadata are correctly handled by LLVM since this commit: https://github.com/llvm/llvm-project/commit/f5b9e11eb8ad