For safety, the inliner cannot decrease the allignment on an alloca when
merging it with another.
I've included two variants of the test case for this: one with DataLayout
available, and one without. When DataLayout is not available, if only one of
the allocas uses the default alignment (getAlignment() == 0), then they cannot
be safely merged.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186425 91177308-0d34-0410-b5e6-96231b3b80d8
