Revert "[AMDGPU] Allow hoisting of comparisons out of a loop and eliminate condition copies"

This reverts commit r286171, it breaks piglit test fs-discard-exit-2

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286530 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed