CodeGen: Avoid dereferencing end() in ScalarExprEmitter::EmitOverflowCheckedBinOp
CodeGen: Avoid dereferencing end() in ScalarExprEmitter::EmitOverflowCheckedBinOp

Use BB.getNextNode(), which returns nullptr on end(), instead of
&*BB.getIterator(), which is UB on end().
CodeGenFunction::createBasicBlock expects nullptr in this case already.

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@278898 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang