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
23using namespace clang;
24
25namespace {
26
27class PPMemoryAllocationsTest : public ::testing::Test {
28protected:
29 PPMemoryAllocationsTest()
30 : FileMgr(FileMgrOpts), DiagID(new DiagnosticIDs()),
31 Diags(DiagID, DiagOpts, new IgnoringDiagConsumer()),
32 SourceMgr(Diags, FileMgr), TargetOpts(new TargetOptions) {
33 TargetOpts->Triple = "x86_64-apple-darwin11.1.0";
34 Target = TargetInfo::CreateTargetInfo(Diags, Opts&: *TargetOpts);
35 }
36
37 FileSystemOptions FileMgrOpts;
38 FileManager FileMgr;
39 IntrusiveRefCntPtr<DiagnosticIDs> DiagID;
40 DiagnosticOptions DiagOpts;
41 DiagnosticsEngine Diags;
42 SourceManager SourceMgr;
43 LangOptions LangOpts;
44 std::shared_ptr<TargetOptions> TargetOpts;
45 IntrusiveRefCntPtr<TargetInfo> Target;
46};
47
48TEST_F(PPMemoryAllocationsTest, PPMacroDefinesAllocations) {
49 std::string Source;
50 size_t NumMacros = 1000000;
51 {
52 llvm::raw_string_ostream SourceOS(Source);
53
54 // Create a combination of 1 or 3 token macros.
55 for (size_t I = 0; I < NumMacros; ++I) {
56 SourceOS << "#define MACRO_ID_" << I << " ";
57 if ((I % 2) == 0)
58 SourceOS << "(" << I << ")";
59 else
60 SourceOS << I;
61 SourceOS << "\n";
62 }
63 }
64
65 std::unique_ptr<llvm::MemoryBuffer> Buf =
66 llvm::MemoryBuffer::getMemBuffer(InputData: Source);
67 SourceMgr.setMainFileID(SourceMgr.createFileID(Buffer: std::move(Buf)));
68
69 HeaderSearchOptions HSOpts;
70 TrivialModuleLoader ModLoader;
71 HeaderSearch HeaderInfo(HSOpts, SourceMgr, Diags, LangOpts, Target.get());
72 PreprocessorOptions PPOpts;
73 Preprocessor PP(PPOpts, Diags, LangOpts, SourceMgr, HeaderInfo, ModLoader,
74 /*IILookup =*/nullptr,
75 /*OwnsHeaderSearch =*/false);
76 PP.Initialize(Target: *Target);
77 PP.EnterMainSourceFile();
78
79 PP.LexTokensUntilEOF();
80
81 size_t NumAllocated = PP.getPreprocessorAllocator().getBytesAllocated();
82 float BytesPerDefine = float(NumAllocated) / float(NumMacros);
83 llvm::errs() << "Num preprocessor allocations for " << NumMacros
84 << " #define: " << NumAllocated << "\n";
85 llvm::errs() << "Bytes per #define: " << BytesPerDefine << "\n";
86 // On arm64-apple-macos, we get around 120 bytes per define.
87 // Assume a reasonable upper bound based on that number that we don't want
88 // to exceed when storing information about a macro #define with 1 or 3
89 // tokens.
90 EXPECT_LT(BytesPerDefine, 130.0f);
91}
92
93} // anonymous namespace
94

source code of clang/unittests/Lex/PPMemoryAllocationsTest.cpp