[llvm] Compute GUIDs once and store in metadata (PR #184065)

[Mircea Trofin via llvm-commits]

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@@ -0,0 +1,31 @@
+//===-- AssignGUID.cpp - Unique identifier assignment pass ------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides a pass which assigns a a GUID (globally unique identifier)
+// to every GlobalValue in the module, according to its current name, linkage,
+// and originating file.
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mtrofin wrote:

add that it leaves things as-is if !guid already present. This may be worth adding in the instructions in getGUID docstring - so people "get it" that moving it or re-adding it in the pipeline somewhere earlier is fine.

https://github.com/llvm/llvm-project/pull/184065