[clang] [llvm] [WebAssembly] Implement the wide-arithmetic proposal (PR #111598)

[Thomas Lively via cfe-commits]

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@@ -0,0 +1,51 @@
+; RUN: llc -mattr=+wide-arithmetic < %s | FileCheck %s
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tlively wrote:

It would be useful to use the auto-update script (utils/update_llc_test_checks.py) here. It will add more test output, but I think that will actually be useful, since it's valuable to see not just that the expected instruction is emitted, but to see that the context looks correct as well.

https://github.com/llvm/llvm-project/pull/111598