Revert "Initial implementation of optimization bisect support."

This reverts commit r267022, due to an ASan failure:

  http://lab.llvm.org:8080/green/job/clang-stage2-cmake-RgSan_check/1549

llvm-svn: 267115
diff --git a/llvm/lib/CodeGen/MachineSink.cpp b/llvm/lib/CodeGen/MachineSink.cpp
index 13924ed..4caa97e 100644
--- a/llvm/lib/CodeGen/MachineSink.cpp
+++ b/llvm/lib/CodeGen/MachineSink.cpp
@@ -257,7 +257,7 @@
 }
 
 bool MachineSinking::runOnMachineFunction(MachineFunction &MF) {
-  if (skipFunction(*MF.getFunction()))
+  if (skipOptnoneFunction(*MF.getFunction()))
     return false;
 
   DEBUG(dbgs() << "******** Machine Sinking ********\n");