[llvm] DAG: Fix cross-block gc.relocate of constants and allocas (PR #222894)

[Kazu Hirata via llvm-commits]

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@@ -0,0 +1,127 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -verify-machineinstrs < %s | FileCheck %s
+; RUN: llc -verify-machineinstrs -early-live-intervals < %s | FileCheck %s
+
+; A gc.relocate of a directly-lowered value (a constant, an alloca, or
+; undef) in an invoke's landing pad must materialize the value at the
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kazutakahirata wrote:

Change `undef` to `poison` in the comment so the `undef deprecator` check in `code_formatter` passes:
```suggestion
; poison) in an invoke's landing pad must materialize the value at the
```

https://github.com/llvm/llvm-project/pull/222894