CodeGen: When emitting stores for an initializer, only emit a GEP if we really need the store.

This avoids emitting many dead GEPs for large zero-initialized arrays.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@162701 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed