Add comment explaining the necessity of r93456
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93459 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LLVMTargetMachine.cpp b/lib/CodeGen/LLVMTargetMachine.cpp
index 8ea6dba..2b5fd2c 100644
--- a/lib/CodeGen/LLVMTargetMachine.cpp
+++ b/lib/CodeGen/LLVMTargetMachine.cpp
@@ -280,6 +280,11 @@
{
case ExceptionHandling::SjLj:
// SjLj piggy-backs on dwarf for this bit. The cleanups done apply to both
+ // Dwarf EH prepare needs to be run after SjLj prepare. Otherwise,
+ // catch info can get misplaced when a selector ends up more than one block
+ // removed from the parent invoke(s). This could happen when a landing
+ // pad is shared by multiple invokes and is also a target of a normal
+ // edge from elsewhere.
PM.add(createSjLjEHPass(getTargetLowering()));
PM.add(createDwarfEHPass(getTargetLowering(), OptLevel==CodeGenOpt::None));
break;