Fix heap-use-after-free bug in expandSDiv when the operands are
constants, as discovered by ASAN.

Patch by Mehdi Amini!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221401 91177308-0d34-0410-b5e6-96231b3b80d8
[Linker] Add some test coverage for llvm.ident merging

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221403 91177308-0d34-0410-b5e6-96231b3b80d8