1//===- ReduceGlobalValues.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 to reduce
10// global value attributes/specifiers.
11//
12//===----------------------------------------------------------------------===//
13
14#include "ReduceGlobalValues.h"
15#include "llvm/IR/GlobalValue.h"
16
17using namespace llvm;
18
19static bool shouldReduceDSOLocal(GlobalValue &GV) {
20 return GV.isDSOLocal() && !GV.isImplicitDSOLocal();
21}
22
23static bool shouldReduceVisibility(GlobalValue &GV) {
24 return GV.getVisibility() != GlobalValue::VisibilityTypes::DefaultVisibility;
25}
26
27static bool shouldReduceUnnamedAddress(GlobalValue &GV) {
28 return GV.getUnnamedAddr() != GlobalValue::UnnamedAddr::None;
29}
30
31static bool shouldReduceDLLStorageClass(GlobalValue &GV) {
32 return GV.getDLLStorageClass() !=
33 GlobalValue::DLLStorageClassTypes::DefaultStorageClass;
34}
35
36static bool shouldReduceThreadLocal(GlobalValue &GV) {
37 return GV.isThreadLocal();
38}
39
40static bool shouldReduceLinkage(GlobalValue &GV) {
41 return !GV.hasExternalLinkage() && !GV.hasAppendingLinkage();
42}
43
44void llvm::reduceGlobalValuesDeltaPass(Oracle &O, ReducerWorkItem &Program) {
45 for (auto &GV : Program.getModule().global_values()) {
46 if (shouldReduceDSOLocal(GV) && !O.shouldKeep())
47 GV.setDSOLocal(false);
48 if (shouldReduceVisibility(GV) && !O.shouldKeep()) {
49 bool IsImplicitDSOLocal = GV.isImplicitDSOLocal();
50 GV.setVisibility(GlobalValue::VisibilityTypes::DefaultVisibility);
51 if (IsImplicitDSOLocal)
52 GV.setDSOLocal(false);
53 }
54 if (shouldReduceUnnamedAddress(GV) && !O.shouldKeep())
55 GV.setUnnamedAddr(GlobalValue::UnnamedAddr::None);
56 if (shouldReduceDLLStorageClass(GV) && !O.shouldKeep())
57 GV.setDLLStorageClass(
58 GlobalValue::DLLStorageClassTypes::DefaultStorageClass);
59 if (shouldReduceThreadLocal(GV) && !O.shouldKeep())
60 GV.setThreadLocal(false);
61 if (shouldReduceLinkage(GV) && !O.shouldKeep()) {
62 bool IsImplicitDSOLocal = GV.isImplicitDSOLocal();
63 GV.setLinkage(GlobalValue::ExternalLinkage);
64 if (IsImplicitDSOLocal)
65 GV.setDSOLocal(false);
66 }
67
68 // TODO: Should this go in a separate reduction?
69 if (auto *GVar = dyn_cast<GlobalVariable>(Val: &GV)) {
70 if (GVar->isExternallyInitialized() && !O.shouldKeep())
71 GVar->setExternallyInitialized(false);
72
73 if (GVar->getCodeModel() && !O.shouldKeep())
74 GVar->clearCodeModel();
75 }
76 }
77}
78