[llvm] unpack packed instructions overlapped by MFMAs post-RA scheduling (PR #157968)

[Jeffrey Byrnes via llvm-commits]

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@@ -0,0 +1,151 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -march=amdgcn -mcpu=gfx950 -run-pass=si-pre-emit-peephole -o - %s | FileCheck -check-prefix=GCN %s
+
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jrbyrnes wrote:

Think we should add tests for all the supported opcodes. We should also add negative tests for a few of the unsupported opcodes.

Add test where the V_PK instruction depends on the V_MFMA. 

Add test where there is a `isNeverCoissue && !isUnpackingSupportedInstr` between V_MFMA and V_PK. 

Also, if you plan to combine the loops, please add a test where the features may interfere.

https://github.com/llvm/llvm-project/pull/157968