DebugInfo: Gut DIExpression
Completely gut `DIExpression`, turning it into a simple wrapper around
`MDExpression *`. There are two bits of magic left:
- It's constructed from `const MDExpression*` but convertible to
`MDExpression*`.
- It's default-constructed to `nullptr`.
Otherwise, it should behave quite like a raw pointer. Once I've done
the same to the rest of the `DIDescriptor` subclasses, I'll come back to
delete them entirely (and update call sites as necessary to deal with
the missing magic).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234832 91177308-0d34-0410-b5e6-96231b3b80d8
8 files changed