[llvm] Handle IMPLICIT_DEF in TripleMBB for WindowScheduler (PR #179190)

[Ryotaro Kasuga via llvm-commits]

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@@ -0,0 +1,54 @@
+# RUN: llc -mtriple=hexagon -run-pass pipeliner %s -o - | FileCheck %s
+# REQUIRES: asserts
+# Ensure WindowScheduler copies IMPLICIT_DEF into the triple-MBB region
+# so LiveIntervals no longer hits LR.verify()
+# CHECK: foo
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kasuga-fj wrote:

If you'd like to verify that the `IMPLICIT_DEF` instructions are copied properly, generating assertions with `utils/update_mir_test_checks.py` may be better.

https://github.com/llvm/llvm-project/pull/179190