Modernize the error handling of the Materialize function.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220600 91177308-0d34-0410-b5e6-96231b3b80d8
[msan] Make -msan-check-constant-shadow a bit stronger.

Allow (under the experimental flag) non-Instructions to participate in MSan checks.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220601 91177308-0d34-0410-b5e6-96231b3b80d8