[llvm] [AArch64][SME][SDAG] Add basic support for exception handling (PR #159363)

[Benjamin Maxwell via llvm-commits]

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@@ -1,5 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
-; RUN: llc -mtriple=aarch64-linux-gnu -mattr=+sme -aarch64-new-sme-abi -verify-machineinstrs < %s | FileCheck %s
+; RUN: llc -mtriple=aarch64-linux-gnu -mattr=+sme2 -aarch64-new-sme-abi -verify-machineinstrs < %s | FileCheck %s
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MacDue wrote:

I'm not sure it's testing anything new. Multiple catches just turn into a single landing-pad then a branch based on the `typeinfo` (and nesting catches just result in another landing-pad). See:  https://godbolt.org/z/9fK3Wxfsn.

https://github.com/llvm/llvm-project/pull/159363