RewriteExpr, either the new PHI node of induction variable or the

RewriteExpr, either the new PHI node of induction variable or the
post-increment value, should be first cast to the appropriated type (to the
type of the common expr). Otherwise, the rewrite of a use based on (common +
iv) may end up with an incorrect type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28735 91177308-0d34-0410-b5e6-96231b3b80d8