Summary:
Add WebAssemblyLateEHPrepare pass that does several small jobs for
exception handling. This runs before CFGSort, and is different from
WasmEHPrepare pass that runs before ISel, even though the names are
similar.
Reviewers: dschuff, majnemer
Subscribers: sbc100, jgravelle-google, sunfish, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D46803
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335438 91177308-0d34-0410-b5e6-96231b3b80d8
