1//===- ReduceSpecialGlobals.cpp - Specialized Delta Pass ------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements a function which calls the Generic Delta pass in order
10// to reduce special globals, like @llvm.used, in the provided Module.
11//
12// For more details about special globals, see
13// https://llvm.org/docs/LangRef.html#intrinsic-global-variables
14//
15//===----------------------------------------------------------------------===//
16
17#include "ReduceSpecialGlobals.h"
18#include "Utils.h"
19#include "llvm/ADT/StringRef.h"
20#include "llvm/IR/GlobalValue.h"
21
22using namespace llvm;
23
24static StringRef SpecialGlobalNames[] = {"llvm.used", "llvm.compiler.used"};
25
26/// Removes all special globals aren't inside any of the
27/// desired Chunks.
28void llvm::reduceSpecialGlobalsDeltaPass(Oracle &O, ReducerWorkItem &WorkItem) {
29 Module &Program = WorkItem.getModule();
30
31 for (StringRef Name : SpecialGlobalNames) {
32 if (auto *Used = Program.getNamedGlobal(Name)) {
33 if (!O.shouldKeep()) {
34 Used->replaceAllUsesWith(V: getDefaultValue(T: Used->getType()));
35 Used->eraseFromParent();
36 }
37 }
38 }
39}
40