1 //===- unittests/Lex/PPMemoryAllocationsTest.cpp - ----------------===//
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 #include "clang/Basic/Diagnostic.h"
10 #include "clang/Basic/DiagnosticOptions.h"
11 #include "clang/Basic/FileManager.h"
12 #include "clang/Basic/LangOptions.h"
13 #include "clang/Basic/SourceManager.h"
14 #include "clang/Basic/TargetInfo.h"
15 #include "clang/Basic/TargetOptions.h"
16 #include "clang/Lex/HeaderSearch.h"
17 #include "clang/Lex/HeaderSearchOptions.h"
18 #include "clang/Lex/ModuleLoader.h"
19 #include "clang/Lex/Preprocessor.h"
20 #include "clang/Lex/PreprocessorOptions.h"
21 #include "gtest/gtest.h"
22
23 using namespace clang;
24
25 namespace {
26
27 class PPMemoryAllocationsTest : public ::testing::Test {
28 protected:
PPMemoryAllocationsTest()29 PPMemoryAllocationsTest()
30 : FileMgr(FileMgrOpts), DiagID(new DiagnosticIDs()),
31 Diags(DiagID, new DiagnosticOptions, new IgnoringDiagConsumer()),
32 SourceMgr(Diags, FileMgr), TargetOpts(new TargetOptions) {
33 TargetOpts->Triple = "x86_64-apple-darwin11.1.0";
34 Target = TargetInfo::CreateTargetInfo(Diags, TargetOpts);
35 }
36
37 FileSystemOptions FileMgrOpts;
38 FileManager FileMgr;
39 IntrusiveRefCntPtr<DiagnosticIDs> DiagID;
40 DiagnosticsEngine Diags;
41 SourceManager SourceMgr;
42 LangOptions LangOpts;
43 std::shared_ptr<TargetOptions> TargetOpts;
44 IntrusiveRefCntPtr<TargetInfo> Target;
45 };
46
TEST_F(PPMemoryAllocationsTest,PPMacroDefinesAllocations)47 TEST_F(PPMemoryAllocationsTest, PPMacroDefinesAllocations) {
48 std::string Source;
49 size_t NumMacros = 1000000;
50 {
51 llvm::raw_string_ostream SourceOS(Source);
52
53 // Create a combination of 1 or 3 token macros.
54 for (size_t I = 0; I < NumMacros; ++I) {
55 SourceOS << "#define MACRO_ID_" << I << " ";
56 if ((I % 2) == 0)
57 SourceOS << "(" << I << ")";
58 else
59 SourceOS << I;
60 SourceOS << "\n";
61 }
62 }
63
64 std::unique_ptr<llvm::MemoryBuffer> Buf =
65 llvm::MemoryBuffer::getMemBuffer(Source);
66 SourceMgr.setMainFileID(SourceMgr.createFileID(std::move(Buf)));
67
68 TrivialModuleLoader ModLoader;
69 HeaderSearch HeaderInfo(std::make_shared<HeaderSearchOptions>(), SourceMgr,
70 Diags, LangOpts, Target.get());
71 Preprocessor PP(std::make_shared<PreprocessorOptions>(), Diags, LangOpts,
72 SourceMgr, HeaderInfo, ModLoader,
73 /*IILookup =*/nullptr,
74 /*OwnsHeaderSearch =*/false);
75 PP.Initialize(*Target);
76 PP.EnterMainSourceFile();
77
78 PP.LexTokensUntilEOF();
79
80 size_t NumAllocated = PP.getPreprocessorAllocator().getBytesAllocated();
81 float BytesPerDefine = float(NumAllocated) / float(NumMacros);
82 llvm::errs() << "Num preprocessor allocations for " << NumMacros
83 << " #define: " << NumAllocated << "\n";
84 llvm::errs() << "Bytes per #define: " << BytesPerDefine << "\n";
85 // On arm64-apple-macos, we get around 120 bytes per define.
86 // Assume a reasonable upper bound based on that number that we don't want
87 // to exceed when storing information about a macro #define with 1 or 3
88 // tokens.
89 EXPECT_LT(BytesPerDefine, 130.0f);
90 }
91
92 } // anonymous namespace
93