[EH] Create removeUnwindEdge utility

Summary:
Factor the code that rewrites invokes to calls and rewrites WinEH
terminators to their "unwind to caller" equivalents into a helper in
Utils/Local, and use it in the three places I'm aware of that need to do
this.


Reviewers: andrew.w.kaylor, majnemer, rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13152

llvm-svn: 248677

1 files changed, 8 insertions, 0 deletions

diff --git a/llvm/include/llvm/Transforms/Utils/Local.h b/llvm/include/llvm/Transforms/Utils/Local.h
index 11c181cbbe0..2354e0ae160 100644
--- a/llvm/include/llvm/Transforms/Utils/Local.h
+++ b/llvm/include/llvm/Transforms/Utils/Local.h
@@ -277,6 +277,14 @@ DbgDeclareInst *FindAllocaDbgDeclare(Value *V);
 bool replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
                                 DIBuilder &Builder, bool Deref);
 
+/// Replace 'BB's terminator with one that does not have an unwind successor
+/// block.  Rewrites `invoke` to `call`, `catchendpad unwind label %foo` to
+/// `catchendpad unwind to caller`, etc.  Updates any PHIs in unwind successor.
+///
+/// \param BB  Block whose terminator will be replaced.  Its terminator must
+///            have an unwind successor.
+void removeUnwindEdge(BasicBlock *BB);
+
 /// \brief Remove all blocks that can not be reached from the function's entry.
 ///
 /// Returns true if any basic block was removed.