A distinction that doesn't _usually_ matter is that the
MachO::SymbolKind is really a mapping of entries in TBD files not
symbols. To better understand this, rename the enum so it represents an
encoding mapped to TBDs as opposed to symbols alone.
For example, it can be a bit confusing that "GlobalSymbol" is a enum
value when all of those values can represent a GlobalSymbol.
Merge allows a user to merge different files (tbds for now or dylibs in
the future) to emit out a single tbd with all input contents. This does
require that all inputs represent the same library.
This is the first of transition tapi-diff to be readtapi.
This tool will eventually replace functionality for Xcode's `xcrun tapi stubify` and
`xcrun tapi archive`.
This patch updates the tool name and is a minor refactor for the driver to handle more options.
Reviewed By: zixuw
Differential Revision: https://reviews.llvm.org/D153045