[WinEH] Stop BranchFolding from merging across funclets
BranchFolding would merge two funclets together, this is not OK.
Disable this and strengthen the assertion in FuncletLayout.
llvm-svn: 249069
diff --git a/llvm/lib/CodeGen/BranchFolding.cpp b/llvm/lib/CodeGen/BranchFolding.cpp
index 2ef8889..2cc851f 100644
--- a/llvm/lib/CodeGen/BranchFolding.cpp
+++ b/llvm/lib/CodeGen/BranchFolding.cpp
@@ -94,9 +94,11 @@
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>());
diff --git a/llvm/lib/CodeGen/FuncletLayout.cpp b/llvm/lib/CodeGen/FuncletLayout.cpp
index e1e185b..4fdb6670 100644
--- a/llvm/lib/CodeGen/FuncletLayout.cpp
+++ b/llvm/lib/CodeGen/FuncletLayout.cpp
@@ -39,17 +39,9 @@
int Funclet, MachineBasicBlock *MBB) {
// Don't revisit blocks.
if (FuncletMembership.count(MBB) > 0) {
- // FIXME: This is a hack, we need to assert this unconditionally.
- bool IsProbablyUnreachableBlock =
- MBB->empty() ||
- (MBB->succ_empty() && !MBB->getFirstTerminator()->isReturn() &&
- MBB->size() == 1);
-
- if (!IsProbablyUnreachableBlock) {
- if (FuncletMembership[MBB] != Funclet) {
- assert(false && "MBB is part of two funclets!");
- report_fatal_error("MBB is part of two funclets!");
- }
+ if (FuncletMembership[MBB] != Funclet) {
+ assert(false && "MBB is part of two funclets!");
+ report_fatal_error("MBB is part of two funclets!");
}
return;
}