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

[Joe Nash 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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Sisyph wrote:

This is interesting. It checks that the script updates existing tests with a pointer in the existing CHECK. IIUC, the script will wipe out any existing CHECK lines and write out new ones, so maybe it is not needed, but it doesn't hurt.

I wonder, does the script work correctly if there is a raw pointer in the LLVM IR or MIR input?

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