[llvm] [GlobalISel] Don't push `freeze`s post-legalizer when that creates illegal instruction (PR #204785)

[Ömer Sinan Ağacan via llvm-commits]

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+# NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+# RUN: llc -mtriple=arm64-apple-macosx -global-isel -start-after=irtranslator -verify-machineinstrs %s -o - | FileCheck %s
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osa1 wrote:

I turned this into a run-pass test.

If you could elaborate what you mean by an IR test I'd be happy to explore that alternative as well.

https://github.com/llvm/llvm-project/pull/204785