[llvm] Change default exception model to Default in RuntimeLibcallsInfo (PR #228555)

[Matt Arsenault via llvm-commits]

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@@ -185,4 +185,13 @@ TEST(RuntimeLibcallsTest, LibcallForIntrinsic) {
             RTLIB::UNKNOWN_LIBCALL);
 }
 
+TEST(RuntimeLibcallsTest, DefaultExceptionModel) {
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arsenm wrote:

Don't think this unit test is necessary 

https://github.com/llvm/llvm-project/pull/228555