R600: Enable -verify-machineinstrs in some tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191788 91177308-0d34-0410-b5e6-96231b3b80d8
R600: Put PRED_X instruction in its own clause

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191789 91177308-0d34-0410-b5e6-96231b3b80d8
R600: add a pass that merges clauses.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191790 91177308-0d34-0410-b5e6-96231b3b80d8