[clang] [llvm] [llvm][fatlto] Add FatLTOCleanup pass (PR #125911)

[Nikita Popov via cfe-commits]

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@@ -0,0 +1,35 @@
+//===- FatLtoCleanup.h - clean up IR for the FatLTO pipeline ----*- 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 defines operations used to clean up IR for the FatLTO pipeline.
+// Instrumentation that is beneficial for bitcode sections used in LTO may
+// need to be cleaned up to finish non-LTO compilation. llvm.checked.load is
+// and example of an instruction that we want to preserve for LTO, but is
+// incorrect to leave unchanged during the per-TU compilation in FatLTO.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_IPO_FATLTOCLEANUP_H
+#define LLVM_TRANSFORMS_IPO_FATLTOCLEANUP_H
+
+#include "llvm/IR/PassManager.h"
+
+namespace llvm {
+
+class Module;
+class ModuleSummaryIndex;
+
+class FatLtoCleanup : public PassInfoMixin<FatLtoCleanup> {
+public:
+  FatLtoCleanup() {}
+  PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM);
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nikic wrote:

Should mark this as isRequired?

https://github.com/llvm/llvm-project/pull/125911