[Tests] Add tests for D60659, and make adjustments to others to make diff clear

Three related changes:
1) auto-gen several test files
2) Add the new tests at the bottom of said files
3) Adjust a couple of other test files not to use stores to constants when trying to test constexpr address handling



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358344 91177308-0d34-0410-b5e6-96231b3b80d8
6 files changed