[llvm] [AArch64][GlobalISel] Don't crash when legalising G_*MIN/G_*MAX of pointer vector (PR #168872)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,174 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
+# RUN: llc -o - -mtriple=aarch64 -run-pass=legalizer -verify-machineinstrs %s | FileCheck %s
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arsenm wrote:

```suggestion
# RUN: llc -o - -mtriple=aarch64 -run-pass=legalizer %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/168872