Re-enable empty block indexing by default, since it doesn't seem to have any
impact on code quality or compile time.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52329 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index f265e63..5bb3cfa 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -44,8 +44,6 @@
                                cl::init(true), cl::Hidden);
 static cl::opt<int> SplitLimit("split-limit",
                                cl::init(-1), cl::Hidden);
-static cl::opt<bool> EmptyBBIndex("empty-bb-index",
-                                  cl::init(false), cl::Hidden);
 
 STATISTIC(numIntervals, "Number of original intervals");
 STATISTIC(numIntervalsAfter, "Number of intervals after coalescing");
@@ -102,23 +100,15 @@
       i2miMap_.push_back(I);
       MIIndex += InstrSlots::NUM;
     }
-
-    // Set the MBB2IdxMap entry for this MBB.
-    if (!EmptyBBIndex) {
-      MBB2IdxMap[MBB->getNumber()] = (StartIdx == MIIndex)
-        ? std::make_pair(StartIdx, StartIdx)  // Empty MBB
-        : std::make_pair(StartIdx, MIIndex - 1);
-      Idx2MBBMap.push_back(std::make_pair(StartIdx, MBB));
-    } else {
-      if (StartIdx == MIIndex) {
-        // Empty MBB
-        MIIndex += InstrSlots::NUM;
-        i2miMap_.push_back(0);
-      }
-      
-      MBB2IdxMap[MBB->getNumber()] = std::make_pair(StartIdx, MIIndex - 1);
-      Idx2MBBMap.push_back(std::make_pair(StartIdx, MBB));
+    
+    if (StartIdx == MIIndex) {
+      // Empty MBB
+      MIIndex += InstrSlots::NUM;
+      i2miMap_.push_back(0);
     }
+    // Set the MBB2IdxMap entry for this MBB.
+    MBB2IdxMap[MBB->getNumber()] = std::make_pair(StartIdx, MIIndex - 1);
+    Idx2MBBMap.push_back(std::make_pair(StartIdx, MBB));
   }
   std::sort(Idx2MBBMap.begin(), Idx2MBBMap.end(), Idx2MBBCompare());
   
@@ -675,9 +665,7 @@
       MIIndex += InstrSlots::NUM;
     }
     
-    if (EmptyBBIndex) {
-      if (MBB->begin() == miEnd) MIIndex += InstrSlots::NUM; // Empty MBB
-    }
+    if (MBB->begin() == miEnd) MIIndex += InstrSlots::NUM; // Empty MBB
   }
 }