[llvm] [MachineLICM] Hoist COPY instruction only when user can be hoisted (PR #81735)

[via llvm-commits]

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@@ -0,0 +1,94 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
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michaelselehov wrote:

I started with autogenerated test, hence the artefact in the NOTE.
But I liked my way of checking much more than the autogeneration. The latter is going to fail from the every little sneeze in the compiler that changes sequence of instructions of register names. Instead my way of checking checks exactly what I want: spill reload in the loop. And when the test fails the error is very clear to read.

https://github.com/llvm/llvm-project/pull/81735