Remove experimental options to control machine block placement.

This reverts r226034. Benchmarking with those flags has not revealed
anything interesting.

llvm-svn: 229648
diff --git a/llvm/lib/CodeGen/MachineBlockPlacement.cpp b/llvm/lib/CodeGen/MachineBlockPlacement.cpp
index ea41b5e..d7aee57 100644
--- a/llvm/lib/CodeGen/MachineBlockPlacement.cpp
+++ b/llvm/lib/CodeGen/MachineBlockPlacement.cpp
@@ -60,17 +60,6 @@
                                                 "blocks in the function."),
                                        cl::init(0), cl::Hidden);
 
-static cl::opt<bool> OnlyHotBadCFGConflictCheck(
-    "only-hot-bad-cfg-conflict-check",
-    cl::desc("Only check that a hot successor doesn't have a hot predecessor."),
-    cl::init(false), cl::Hidden);
-
-static cl::opt<bool> NoBadCFGConflictCheck(
-    "no-bad-cfg-conflict-check",
-    cl::desc("Don't check whether a hot successor has a more important "
-             "predecessor."),
-    cl::init(false), cl::Hidden);
-
 // FIXME: Find a good default for this flag and remove the flag.
 static cl::opt<unsigned>
 ExitBlockBias("block-placement-exit-block-bias",
@@ -385,33 +374,29 @@
         continue;
       }
 
-      if (!NoBadCFGConflictCheck) {
-        // Make sure that a hot successor doesn't have a globally more
-        // important predecessor.
-        BlockFrequency CandidateEdgeFreq =
-            OnlyHotBadCFGConflictCheck
-                ? MBFI->getBlockFreq(BB) * SuccProb
-                : MBFI->getBlockFreq(BB) * SuccProb * HotProb.getCompl();
-        bool BadCFGConflict = false;
-        for (MachineBasicBlock::pred_iterator PI = (*SI)->pred_begin(),
-                                              PE = (*SI)->pred_end();
-             PI != PE; ++PI) {
-          if (*PI == *SI || (BlockFilter && !BlockFilter->count(*PI)) ||
-              BlockToChain[*PI] == &Chain)
-            continue;
-          BlockFrequency PredEdgeFreq =
-              MBFI->getBlockFreq(*PI) * MBPI->getEdgeProbability(*PI, *SI);
-          if (PredEdgeFreq >= CandidateEdgeFreq) {
-            BadCFGConflict = true;
-            break;
-          }
-        }
-        if (BadCFGConflict) {
-          DEBUG(dbgs() << "    " << getBlockName(*SI) << " -> " << SuccProb
-                       << " (prob) (non-cold CFG conflict)\n");
+      // Make sure that a hot successor doesn't have a globally more
+      // important predecessor.
+      BlockFrequency CandidateEdgeFreq =
+          MBFI->getBlockFreq(BB) * SuccProb * HotProb.getCompl();
+      bool BadCFGConflict = false;
+      for (MachineBasicBlock::pred_iterator PI = (*SI)->pred_begin(),
+                                            PE = (*SI)->pred_end();
+           PI != PE; ++PI) {
+        if (*PI == *SI || (BlockFilter && !BlockFilter->count(*PI)) ||
+            BlockToChain[*PI] == &Chain)
           continue;
+        BlockFrequency PredEdgeFreq =
+            MBFI->getBlockFreq(*PI) * MBPI->getEdgeProbability(*PI, *SI);
+        if (PredEdgeFreq >= CandidateEdgeFreq) {
+          BadCFGConflict = true;
+          break;
         }
       }
+      if (BadCFGConflict) {
+        DEBUG(dbgs() << "    " << getBlockName(*SI) << " -> " << SuccProb
+                     << " (prob) (non-cold CFG conflict)\n");
+        continue;
+      }
     }
 
     DEBUG(dbgs() << "    " << getBlockName(*SI) << " -> " << SuccProb