[llvm] [AMDGPU] Reset minOccupancy if unclustered schedule was not run for any region. (PR #162025)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,735 @@
+# RUN: llc -mtriple=amdgcn -mcpu=gfx1100 -start-before=machine-scheduler -stop-after=greedy,2 -amdgpu-use-amdgpu-trackers=1 -verify-machineinstrs -debug-only=machine-scheduler %s -o - 2>&1 | FileCheck %s
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arsenm wrote:

```suggestion
# REQUIRES: asserts
# RUN: llc -mtriple=amdgcn -mcpu=gfx1100 -start-before=machine-scheduler -stop-after=greedy,2 -amdgpu-use-amdgpu-trackers -debug-only=machine-scheduler %s -o - 2>&1 | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/162025