Also create isValidElementType for ArrayType, PointerType, StructType and
VectorType.
Make LLParser use them. This closes up some holes like an assertion failure on:
%x = type {label}
but largely doesn't change any semantics. The only thing we accept now which
we didn't before is vectors of opaque type such as "<4 x opaque>". The opaque
can be resolved to an int or float when linking.
llvm-svn: 73016
0aa6a74a79