[llvm] [PowerPC] Add test after #75271 on PPC. NFC. (PR #75616)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,9039 @@
+# RUN: llc -mtriple=powerpc64le-unknown-linux-gnu -verify-coalescing -run-pass=register-coalescer \
+# RUN:   -o - %s | FileCheck %s
+--- |
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arsenm wrote:

This test case is much too big. Can you try running it through llvm-reduce MIR handling? That will likely remove most of the cruft. Then you can delete the IR and registers sections, and run through -run-pass=none to do some additional cleanups 

https://github.com/llvm/llvm-project/pull/75616