[llvm] InstCombine: Fix a crash in `PointerReplacer` when constructing a new PHI (PR #130256)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,48 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -O1 -S -o - %s | FileCheck %s
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arsenm wrote:

Should just run instcombine and not -O1 

https://github.com/llvm/llvm-project/pull/130256