[llvm] [AMDGPU][Scheduler] Fix non-monotonic SlotIndex after schedule revert (PR #192039)

[via llvm-commits]

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@@ -0,0 +1,738 @@
+# RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx908 -run-pass=machine-scheduler -o /dev/null %s
+# Verify that modifyRegionSchedule does not leave non-monotonic SlotIndexes
+# when reverting a schedule. This used to crash with "register isn't live"
+# in GCNDownwardRPTracker::advanceBeforeNext().
+---
+name:            _ZN2ck27kernel_gemm_xdl_cshuffle_v3INS_28GridwiseGemm_xdl_cshuffle_v3INS_13tensor_layout4gemm11ColumnMajorENS3_8RowMajorES5_ttfttNS_16tensor_operation12element_wise11PassThroughES8_S8_LNS6_6device18GemmSpecializationE7ELi256ELi128ELi128ELi64ELi4ELi4ELi32ELi32ELi2ELi2ENS_8SequenceIJLi16ELi16ELi1EEEENSB_IJLi0ELi2ELi1EEEESD_Li1ELi8ELi4ELb0ELi0ESC_SD_SD_Li1ELi8ELi4ELb0ELi0ELi1ELi1ENSB_IJLi1ELi16ELi1ELi16EEEELi4ELNS_26BlockGemmPipelineSchedulerE0ELNS_24BlockGemmPipelineVersionE4EttLb0ELb0ELb0EEELb1ELNS_25InMemoryDataOperationEnumE1ELi1ELNS_10TailNumberE0EEEvNT_8ArgumentE
+alignment:       4
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michaelselehov wrote:

Done, stripped down to `tracksRegLiveness` + `machineFunctionInfo: isEntryFunction`.

https://github.com/llvm/llvm-project/pull/192039