[WinEH] Stop BranchFolding from merging across funclets

[oota-llvm.git] / lib / CodeGen / BranchFolding.cpp

diff --git a/lib/CodeGen/BranchFolding.cpp b/lib/CodeGen/BranchFolding.cpp
index 2ef8889091f1eeb1cd380917608352bf4c48ca4d..2cc851f3973cac272d7914037b254a2abbc94062 100644 (file)
--- a/lib/CodeGen/BranchFolding.cpp
+++ b/lib/CodeGen/BranchFolding.cpp
@@ -94,9 +94,11 @@ bool BranchFolderPass::runOnMachineFunction(MachineFunction &MF) {
 
   TargetPassConfig *PassConfig = &getAnalysis<TargetPassConfig>();
   // TailMerge can create jump into if branches that make CFG irreducible for
-  // HW that requires structurized CFG.
+  // HW that requires structurized CFG.  It can also cause BBs to get shared
+  // between funclets.
   bool EnableTailMerge = !MF.getTarget().requiresStructuredCFG() &&
-      PassConfig->getEnableTailMerge();
+                         !MF.getMMI().hasEHFunclets() &&
+                         PassConfig->getEnableTailMerge();
   BranchFolder Folder(EnableTailMerge, /*CommonHoist=*/true,
                       getAnalysis<MachineBlockFrequencyInfo>(),
                       getAnalysis<MachineBranchProbabilityInfo>());