Index: include/llvm/CodeGen/TailDuplicator.h
===================================================================
--- include/llvm/CodeGen/TailDuplicator.h
+++ include/llvm/CodeGen/TailDuplicator.h
@@ -27,6 +27,8 @@
 
 namespace llvm {
 
+extern cl::opt<unsigned> TailDupIndirectBranchSize;
+
 /// Utility class to perform tail duplication.
 class TailDuplicator {
   const TargetInstrInfo *TII;
Index: lib/CodeGen/TailDuplicator.cpp
===================================================================
--- lib/CodeGen/TailDuplicator.cpp
+++ lib/CodeGen/TailDuplicator.cpp
@@ -41,12 +41,20 @@
 STATISTIC(NumDeadBlocks, "Number of dead blocks removed");
 STATISTIC(NumAddedPHIs, "Number of phis added");
 
+namespace llvm {
+
 // Heuristic for tail duplication.
 static cl::opt<unsigned> TailDuplicateSize(
     "tail-dup-size",
     cl::desc("Maximum instructions to consider tail duplicating"), cl::init(2),
     cl::Hidden);
 
+cl::opt<unsigned> TailDupIndirectBranchSize(
+    "tail-dup-indirect-size",
+    cl::desc("Maximum instructions to consider tail duplicating blocks that "
+             "end with indirect branches."), cl::init(20),
+    cl::Hidden);
+
 static cl::opt<bool>
     TailDupVerify("tail-dup-verify",
                   cl::desc("Verify sanity of PHI instructions during taildup"),
@@ -55,8 +63,6 @@
 static cl::opt<unsigned> TailDupLimit("tail-dup-limit", cl::init(~0U),
                                       cl::Hidden);
 
-namespace llvm {
-
 void TailDuplicator::initMF(MachineFunction &MFin,
                             const MachineBranchProbabilityInfo *MBPIin,
                             MachineLoopInfo *MLIin,
@@ -583,7 +589,7 @@
   }
 
   if (HasIndirectbr && (PreRegAlloc || LayoutMode))
-    MaxDuplicateCount = 20;
+    MaxDuplicateCount = TailDupIndirectBranchSize;
 
   // Check the instructions in the block to determine whether tail-duplication
   // is invalid or unlikely to be profitable.