Allow Post-RA LICM to hoist reserved register reads.

When using register masks, registers like %rip are clobbered by the
register mask. LICM should still be able to hoist instructions reading
%rip from a loop containing calls.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150288 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed