[llvm] Revert "Revert "[AMDGPU][LTO] Assume closed world after linking (#105845)" (#106000)" (PR #106001)

[NAKAMURA Takumi via llvm-commits]

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@@ -0,0 +1,12 @@
+; RUN: opt -O3 -debug-only=amdgpu-attributor -S -o - %s 2>&1 | FileCheck %s --check-prefix=PRE-LINK
+; RUN: opt -passes="lto<O3>" -debug-only=amdgpu-attributor -S -o - %s 2>&1 | FileCheck %s --check-prefix=POST-LINK
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chapuni wrote:

`-debug-only` won't work wth `LLVM_ENABLE_ASSERTIONS=OFF`.

https://github.com/llvm/llvm-project/pull/106001