[llvm] [InstCombine]PtrReplacer: Correctly handle select with unavailable operands (PR #148829)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,20 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -mtriple=amdgcn-amd-amdhsa -passes=instcombine %s -S -o - | FileCheck %s
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arsenm wrote:

```suggestion
; RUN: opt -S -mtriple=amdgcn-amd-amdhsa -passes=instcombine < %s  | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/148829