Finish materialize for ints

Summary: We add code to materialize all integer literals.

Test Plan: simplestorei.ll

Reviewers: dsanders

Reviewed By: dsanders

Differential Revision: http://reviews.llvm.org/D3596

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208923 91177308-0d34-0410-b5e6-96231b3b80d8