Branch Folding: Accept explicit threshold for tail merge size.

This is prep work for allowing the threshold to be different during layout,
and to enforce a single threshold between merging and duplicating during
layout. No observable change intended.

llvm-svn: 279117

1 files changed, 3 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/MachineBlockPlacement.cpp b/llvm/lib/CodeGen/MachineBlockPlacement.cpp
index 88457ba8..37055af 100644
--- a/llvm/lib/CodeGen/MachineBlockPlacement.cpp
+++ b/llvm/lib/CodeGen/MachineBlockPlacement.cpp
@@ -1747,8 +1747,10 @@ bool MachineBlockPlacement::runOnMachineFunction(MachineFunction &MF) {
                          BranchFoldPlacement;
   // No tail merging opportunities if the block number is less than four.
   if (MF.size() > 3 && EnableTailMerge) {
+    // Default to the standard tail-merge-size option.
+    unsigned TailMergeSize = 0;
     BranchFolder BF(/*EnableTailMerge=*/true, /*CommonHoist=*/false, *MBFI,
-                    *MBPI);
+                    *MBPI, TailMergeSize);
 
     if (BF.OptimizeFunction(MF, TII, MF.getSubtarget().getRegisterInfo(),
                             getAnalysisIfAvailable<MachineModuleInfo>(), MLI,