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/PostRASchedulerList.cpp b/llvm/lib/CodeGen/PostRASchedulerList.cpp
index 79958c9..ad9f946 100644
--- a/llvm/lib/CodeGen/PostRASchedulerList.cpp
+++ b/llvm/lib/CodeGen/PostRASchedulerList.cpp
@@ -273,7 +273,7 @@
 }
 
 bool PostRAScheduler::runOnMachineFunction(MachineFunction &Fn) {
-  if (skipFunction(*Fn.getFunction()))
+  if (skipOptnoneFunction(*Fn.getFunction()))
     return false;
 
   TII = Fn.getSubtarget().getInstrInfo();