llvm-project/clang/unittests/Frontend/PCHPreambleTest.cpp

266 lines
8.7 KiB
C++

//====-- unittests/Frontend/PCHPreambleTest.cpp - FrontendAction tests ---====//
//
// 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
//
//===----------------------------------------------------------------------===//
#include "clang/Frontend/ASTUnit.h"
#include "clang/Frontend/CompilerInvocation.h"
#include "clang/Frontend/CompilerInstance.h"
#include "clang/Frontend/FrontendActions.h"
#include "clang/Frontend/FrontendOptions.h"
#include "clang/Lex/PreprocessorOptions.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/FileManager.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Path.h"
#include "gtest/gtest.h"
using namespace llvm;
using namespace clang;
namespace {
class ReadCountingInMemoryFileSystem : public vfs::InMemoryFileSystem
{
std::map<std::string, unsigned> ReadCounts;
public:
ErrorOr<std::unique_ptr<vfs::File>> openFileForRead(const Twine &Path) override
{
SmallVector<char, 128> PathVec;
Path.toVector(PathVec);
llvm::sys::path::remove_dots(PathVec, true);
++ReadCounts[std::string(PathVec.begin(), PathVec.end())];
return InMemoryFileSystem::openFileForRead(Path);
}
unsigned GetReadCount(const Twine &Path) const
{
auto it = ReadCounts.find(Path.str());
return it == ReadCounts.end() ? 0 : it->second;
}
};
class PCHPreambleTest : public ::testing::Test {
IntrusiveRefCntPtr<ReadCountingInMemoryFileSystem> VFS;
StringMap<std::string> RemappedFiles;
std::shared_ptr<PCHContainerOperations> PCHContainerOpts;
FileSystemOptions FSOpts;
public:
void SetUp() override { ResetVFS(); }
void TearDown() override {}
void ResetVFS() {
VFS = new ReadCountingInMemoryFileSystem();
// We need the working directory to be set to something absolute,
// otherwise it ends up being inadvertently set to the current
// working directory in the real file system due to a series of
// unfortunate conditions interacting badly.
// What's more, this path *must* be absolute on all (real)
// filesystems, so just '/' won't work (e.g. on Win32).
VFS->setCurrentWorkingDirectory("//./");
}
void AddFile(const std::string &Filename, const std::string &Contents) {
::time_t now;
::time(&now);
VFS->addFile(Filename, now, MemoryBuffer::getMemBufferCopy(Contents, Filename));
}
void RemapFile(const std::string &Filename, const std::string &Contents) {
RemappedFiles[Filename] = Contents;
}
std::unique_ptr<ASTUnit> ParseAST(const std::string &EntryFile) {
PCHContainerOpts = std::make_shared<PCHContainerOperations>();
std::shared_ptr<CompilerInvocation> CI(new CompilerInvocation);
CI->getFrontendOpts().Inputs.push_back(
FrontendInputFile(EntryFile, FrontendOptions::getInputKindForExtension(
llvm::sys::path::extension(EntryFile).substr(1))));
CI->getTargetOpts().Triple = "i386-unknown-linux-gnu";
CI->getPreprocessorOpts().RemappedFileBuffers = GetRemappedFiles();
PreprocessorOptions &PPOpts = CI->getPreprocessorOpts();
PPOpts.RemappedFilesKeepOriginalName = true;
IntrusiveRefCntPtr<DiagnosticsEngine>
Diags(CompilerInstance::createDiagnostics(new DiagnosticOptions, new DiagnosticConsumer));
FileManager *FileMgr = new FileManager(FSOpts, VFS);
std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromCompilerInvocation(
CI, PCHContainerOpts, Diags, FileMgr, false, CaptureDiagsKind::None,
/*PrecompilePreambleAfterNParses=*/1);
return AST;
}
bool ReparseAST(const std::unique_ptr<ASTUnit> &AST) {
bool reparseFailed = AST->Reparse(PCHContainerOpts, GetRemappedFiles(), VFS);
return !reparseFailed;
}
unsigned GetFileReadCount(const std::string &Filename) const {
return VFS->GetReadCount(Filename);
}
private:
std::vector<std::pair<std::string, llvm::MemoryBuffer *>>
GetRemappedFiles() const {
std::vector<std::pair<std::string, llvm::MemoryBuffer *>> Remapped;
for (const auto &RemappedFile : RemappedFiles) {
std::unique_ptr<MemoryBuffer> buf = MemoryBuffer::getMemBufferCopy(
RemappedFile.second, RemappedFile.first());
Remapped.emplace_back(std::string(RemappedFile.first()), buf.release());
}
return Remapped;
}
};
TEST_F(PCHPreambleTest, ReparseReusesPreambleWithUnsavedFileNotExistingOnDisk) {
std::string Header1 = "//./header1.h";
std::string MainName = "//./main.cpp";
AddFile(MainName, R"cpp(
#include "//./header1.h"
int main() { return ZERO; }
)cpp");
RemapFile(Header1, "#define ZERO 0\n");
// Parse with header file provided as unsaved file, which does not exist on
// disk.
std::unique_ptr<ASTUnit> AST(ParseAST(MainName));
ASSERT_TRUE(AST.get());
ASSERT_FALSE(AST->getDiagnostics().hasErrorOccurred());
// Reparse and check that the preamble was reused.
ASSERT_TRUE(ReparseAST(AST));
ASSERT_EQ(AST->getPreambleCounterForTests(), 1U);
}
TEST_F(PCHPreambleTest, ReparseReusesPreambleAfterUnsavedFileWasCreatedOnDisk) {
std::string Header1 = "//./header1.h";
std::string MainName = "//./main.cpp";
AddFile(MainName, R"cpp(
#include "//./header1.h"
int main() { return ZERO; }
)cpp");
RemapFile(Header1, "#define ZERO 0\n");
// Parse with header file provided as unsaved file, which does not exist on
// disk.
std::unique_ptr<ASTUnit> AST(ParseAST(MainName));
ASSERT_TRUE(AST.get());
ASSERT_FALSE(AST->getDiagnostics().hasErrorOccurred());
// Create the unsaved file also on disk and check that preamble was reused.
AddFile(Header1, "#define ZERO 0\n");
ASSERT_TRUE(ReparseAST(AST));
ASSERT_EQ(AST->getPreambleCounterForTests(), 1U);
}
TEST_F(PCHPreambleTest,
ReparseReusesPreambleAfterUnsavedFileWasRemovedFromDisk) {
std::string Header1 = "//./foo/header1.h";
std::string MainName = "//./main.cpp";
std::string MainFileContent = R"cpp(
#include "//./foo/header1.h"
int main() { return ZERO; }
)cpp";
AddFile(MainName, MainFileContent);
AddFile(Header1, "#define ZERO 0\n");
RemapFile(Header1, "#define ZERO 0\n");
// Parse with header file provided as unsaved file, which exists on disk.
std::unique_ptr<ASTUnit> AST(ParseAST(MainName));
ASSERT_TRUE(AST.get());
ASSERT_FALSE(AST->getDiagnostics().hasErrorOccurred());
ASSERT_EQ(AST->getPreambleCounterForTests(), 1U);
// Remove the unsaved file from disk and check that the preamble was reused.
ResetVFS();
AddFile(MainName, MainFileContent);
ASSERT_TRUE(ReparseAST(AST));
ASSERT_EQ(AST->getPreambleCounterForTests(), 1U);
}
TEST_F(PCHPreambleTest, ReparseWithOverriddenFileDoesNotInvalidatePreamble) {
std::string Header1 = "//./header1.h";
std::string Header2 = "//./header2.h";
std::string MainName = "//./main.cpp";
AddFile(Header1, "");
AddFile(Header2, "#pragma once");
AddFile(MainName,
"#include \"//./foo/../header1.h\"\n"
"#include \"//./foo/../header2.h\"\n"
"int main() { return ZERO; }");
RemapFile(Header1, "static const int ZERO = 0;\n");
std::unique_ptr<ASTUnit> AST(ParseAST(MainName));
ASSERT_TRUE(AST.get());
ASSERT_FALSE(AST->getDiagnostics().hasErrorOccurred());
unsigned initialCounts[] = {
GetFileReadCount(MainName),
GetFileReadCount(Header1),
GetFileReadCount(Header2)
};
ASSERT_TRUE(ReparseAST(AST));
ASSERT_NE(initialCounts[0], GetFileReadCount(MainName));
ASSERT_EQ(initialCounts[1], GetFileReadCount(Header1));
ASSERT_EQ(initialCounts[2], GetFileReadCount(Header2));
}
TEST_F(PCHPreambleTest, ParseWithBom) {
std::string Header = "//./header.h";
std::string Main = "//./main.cpp";
AddFile(Header, "int random() { return 4; }");
AddFile(Main,
"\xef\xbb\xbf"
"#include \"//./header.h\"\n"
"int main() { return random() -2; }");
std::unique_ptr<ASTUnit> AST(ParseAST(Main));
ASSERT_TRUE(AST.get());
ASSERT_FALSE(AST->getDiagnostics().hasErrorOccurred());
unsigned HeaderReadCount = GetFileReadCount(Header);
ASSERT_TRUE(ReparseAST(AST));
ASSERT_FALSE(AST->getDiagnostics().hasErrorOccurred());
// Check preamble PCH was really reused
ASSERT_EQ(HeaderReadCount, GetFileReadCount(Header));
// Remove BOM
RemapFile(Main,
"#include \"//./header.h\"\n"
"int main() { return random() -2; }");
ASSERT_TRUE(ReparseAST(AST));
ASSERT_FALSE(AST->getDiagnostics().hasErrorOccurred());
ASSERT_LE(HeaderReadCount, GetFileReadCount(Header));
HeaderReadCount = GetFileReadCount(Header);
// Add BOM back
RemapFile(Main,
"\xef\xbb\xbf"
"#include \"//./header.h\"\n"
"int main() { return random() -2; }");
ASSERT_TRUE(ReparseAST(AST));
ASSERT_FALSE(AST->getDiagnostics().hasErrorOccurred());
ASSERT_LE(HeaderReadCount, GetFileReadCount(Header));
}
} // anonymous namespace