We record the type of the symbol (event/function/data/global) in the
MCWasmSymbol and so it should always be clear how to handle a relocation
based on the symbol itself.
The exception is a function which still needs the special @TYPEINDEX
then the relocation contains the signature rather than the address
of the functions.
Differential Revision: https://reviews.llvm.org/D58472
llvm-svn: 354697