Map from a function context MD5 to its FunctionSamples file offset.
Declared in <llvm/ProfileData/SampleProfReader.h>
std::optional<SampleProfileFuncOffsetTable> FuncOffsetTable;The table mapping from a function context's MD5 to the offset of its FunctionSample towards file start. At most one of FuncOffsetTable and FuncOffsetList is populated.