[llvm] [RegAlloc] Avoid split past block-prologue interference (PR #209704)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,105 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
+# RUN: llc -mtriple=amdgpu9.00-amd-amdhsa -stress-regalloc=2 -passes='greedy<wwm>' -o - %s | FileCheck %s
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arsenm wrote:

There is because it requires the hacky -start-before...stop-after sequence to get the right filter 

https://github.com/llvm/llvm-project/pull/209704