[llvm] Add metadata pointer regex substitution to MIR update script (PR #163253)

[via llvm-commits]

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@@ -0,0 +1,29 @@
+; NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -global-isel -mtriple=amdgcn -mcpu=gfx900 -stop-after=irtranslator -o - %s | FileCheck %s
+
+define i32 @reloc_constant() {
+  ; CHECK-LABEL: name: reloc_constant
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saxlungs wrote:

Per external conversation, the entirety of the `llvm/test/` directory has no examples of this, so we think it's safe to assume that won't happen

https://github.com/llvm/llvm-project/pull/163253