llvm-project/clang/unittests/Lex/PPCallbacksTest.cpp
Duncan P. N. Exon Smith 079c40e886 Modules: Cache PCMs in memory and avoid a use-after-free
Clang's internal build system for implicit modules uses lock files to
ensure that after a process writes a PCM it will read the same one back
in (without contention from other -cc1 commands).  Since PCMs are read
from disk repeatedly while invalidating, building, and importing, the
lock is not released quickly.  Furthermore, the LockFileManager is not
robust in every environment.  Other -cc1 commands can stall until
timeout (after about eight minutes).

This commit changes the lock file from being necessary for correctness
to a (possibly dubious) performance hack.  The remaining benefit is to
reduce duplicate work in competing -cc1 commands which depend on the
same module.  Follow-up commits will change the internal build system to
continue after a timeout, and reduce the timeout.  Perhaps we should
reconsider blocking at all.

This also fixes a use-after-free, when one part of a compilation
validates a PCM and starts using it, and another tries to swap out the
PCM for something new.

The PCMCache is a new type called MemoryBufferCache, which saves memory
buffers based on their filename.  Its ownership is shared by the
CompilerInstance and ModuleManager.

  - The ModuleManager stores PCMs there that it loads from disk, never
    touching the disk if the cache is hot.

  - When modules fail to validate, they're removed from the cache.

  - When a CompilerInstance is spawned to build a new module, each
    already-loaded PCM is assumed to be valid, and is frozen to avoid
    the use-after-free.

  - Any newly-built module is written directly to the cache to avoid the
    round-trip to the filesystem, making lock files unnecessary for
    correctness.

Original patch by Manman Ren; most testcases by Adrian Prantl!

llvm-svn: 298165
2017-03-17 22:55:13 +00:00

355 lines
11 KiB
C++

//===- unittests/Lex/PPCallbacksTest.cpp - PPCallbacks tests ------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===--------------------------------------------------------------===//
#include "clang/Lex/Preprocessor.h"
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/ASTContext.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/DiagnosticOptions.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/LangOptions.h"
#include "clang/Basic/MemoryBufferCache.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Basic/TargetOptions.h"
#include "clang/Lex/HeaderSearch.h"
#include "clang/Lex/HeaderSearchOptions.h"
#include "clang/Lex/ModuleLoader.h"
#include "clang/Lex/PreprocessorOptions.h"
#include "clang/Parse/Parser.h"
#include "clang/Sema/Sema.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/Support/Path.h"
#include "gtest/gtest.h"
using namespace clang;
namespace {
// Stub out module loading.
class VoidModuleLoader : public ModuleLoader {
ModuleLoadResult loadModule(SourceLocation ImportLoc,
ModuleIdPath Path,
Module::NameVisibilityKind Visibility,
bool IsInclusionDirective) override {
return ModuleLoadResult();
}
void makeModuleVisible(Module *Mod,
Module::NameVisibilityKind Visibility,
SourceLocation ImportLoc) override { }
GlobalModuleIndex *loadGlobalModuleIndex(SourceLocation TriggerLoc) override
{ return nullptr; }
bool lookupMissingImports(StringRef Name, SourceLocation TriggerLoc) override
{ return 0; }
};
// Stub to collect data from InclusionDirective callbacks.
class InclusionDirectiveCallbacks : public PPCallbacks {
public:
void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
StringRef FileName, bool IsAngled,
CharSourceRange FilenameRange, const FileEntry *File,
StringRef SearchPath, StringRef RelativePath,
const Module *Imported) override {
this->HashLoc = HashLoc;
this->IncludeTok = IncludeTok;
this->FileName = FileName.str();
this->IsAngled = IsAngled;
this->FilenameRange = FilenameRange;
this->File = File;
this->SearchPath = SearchPath.str();
this->RelativePath = RelativePath.str();
this->Imported = Imported;
}
SourceLocation HashLoc;
Token IncludeTok;
SmallString<16> FileName;
bool IsAngled;
CharSourceRange FilenameRange;
const FileEntry* File;
SmallString<16> SearchPath;
SmallString<16> RelativePath;
const Module* Imported;
};
// Stub to collect data from PragmaOpenCLExtension callbacks.
class PragmaOpenCLExtensionCallbacks : public PPCallbacks {
public:
typedef struct {
SmallString<16> Name;
unsigned State;
} CallbackParameters;
PragmaOpenCLExtensionCallbacks() : Name("Not called."), State(99) {}
void PragmaOpenCLExtension(clang::SourceLocation NameLoc,
const clang::IdentifierInfo *Name,
clang::SourceLocation StateLoc,
unsigned State) override {
this->NameLoc = NameLoc;
this->Name = Name->getName();
this->StateLoc = StateLoc;
this->State = State;
}
SourceLocation NameLoc;
SmallString<16> Name;
SourceLocation StateLoc;
unsigned State;
};
// PPCallbacks test fixture.
class PPCallbacksTest : public ::testing::Test {
protected:
PPCallbacksTest()
: InMemoryFileSystem(new vfs::InMemoryFileSystem),
FileMgr(FileSystemOptions(), InMemoryFileSystem),
DiagID(new DiagnosticIDs()), DiagOpts(new DiagnosticOptions()),
Diags(DiagID, DiagOpts.get(), new IgnoringDiagConsumer()),
SourceMgr(Diags, FileMgr), TargetOpts(new TargetOptions()) {
TargetOpts->Triple = "x86_64-apple-darwin11.1.0";
Target = TargetInfo::CreateTargetInfo(Diags, TargetOpts);
}
IntrusiveRefCntPtr<vfs::InMemoryFileSystem> InMemoryFileSystem;
FileManager FileMgr;
IntrusiveRefCntPtr<DiagnosticIDs> DiagID;
IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts;
DiagnosticsEngine Diags;
SourceManager SourceMgr;
LangOptions LangOpts;
std::shared_ptr<TargetOptions> TargetOpts;
IntrusiveRefCntPtr<TargetInfo> Target;
// Register a header path as a known file and add its location
// to search path.
void AddFakeHeader(HeaderSearch& HeaderInfo, const char* HeaderPath,
bool IsSystemHeader) {
// Tell FileMgr about header.
InMemoryFileSystem->addFile(HeaderPath, 0,
llvm::MemoryBuffer::getMemBuffer("\n"));
// Add header's parent path to search path.
StringRef SearchPath = llvm::sys::path::parent_path(HeaderPath);
const DirectoryEntry *DE = FileMgr.getDirectory(SearchPath);
DirectoryLookup DL(DE, SrcMgr::C_User, false);
HeaderInfo.AddSearchPath(DL, IsSystemHeader);
}
// Get the raw source string of the range.
StringRef GetSourceString(CharSourceRange Range) {
const char* B = SourceMgr.getCharacterData(Range.getBegin());
const char* E = SourceMgr.getCharacterData(Range.getEnd());
return StringRef(B, E - B);
}
// Run lexer over SourceText and collect FilenameRange from
// the InclusionDirective callback.
CharSourceRange InclusionDirectiveFilenameRange(const char* SourceText,
const char* HeaderPath, bool SystemHeader) {
std::unique_ptr<llvm::MemoryBuffer> Buf =
llvm::MemoryBuffer::getMemBuffer(SourceText);
SourceMgr.setMainFileID(SourceMgr.createFileID(std::move(Buf)));
VoidModuleLoader ModLoader;
MemoryBufferCache PCMCache;
HeaderSearch HeaderInfo(std::make_shared<HeaderSearchOptions>(), SourceMgr,
Diags, LangOpts, Target.get());
AddFakeHeader(HeaderInfo, HeaderPath, SystemHeader);
Preprocessor PP(std::make_shared<PreprocessorOptions>(), Diags, LangOpts,
SourceMgr, PCMCache, HeaderInfo, ModLoader,
/*IILookup =*/nullptr,
/*OwnsHeaderSearch =*/false);
PP.Initialize(*Target);
InclusionDirectiveCallbacks* Callbacks = new InclusionDirectiveCallbacks;
PP.addPPCallbacks(std::unique_ptr<PPCallbacks>(Callbacks));
// Lex source text.
PP.EnterMainSourceFile();
while (true) {
Token Tok;
PP.Lex(Tok);
if (Tok.is(tok::eof))
break;
}
// Callbacks have been executed at this point -- return filename range.
return Callbacks->FilenameRange;
}
PragmaOpenCLExtensionCallbacks::CallbackParameters
PragmaOpenCLExtensionCall(const char* SourceText) {
LangOptions OpenCLLangOpts;
OpenCLLangOpts.OpenCL = 1;
std::unique_ptr<llvm::MemoryBuffer> SourceBuf =
llvm::MemoryBuffer::getMemBuffer(SourceText, "test.cl");
SourceMgr.setMainFileID(SourceMgr.createFileID(std::move(SourceBuf)));
VoidModuleLoader ModLoader;
MemoryBufferCache PCMCache;
HeaderSearch HeaderInfo(std::make_shared<HeaderSearchOptions>(), SourceMgr,
Diags, OpenCLLangOpts, Target.get());
Preprocessor PP(std::make_shared<PreprocessorOptions>(), Diags,
OpenCLLangOpts, SourceMgr, PCMCache, HeaderInfo, ModLoader,
/*IILookup =*/nullptr,
/*OwnsHeaderSearch =*/false);
PP.Initialize(*Target);
// parser actually sets correct pragma handlers for preprocessor
// according to LangOptions, so we init Parser to register opencl
// pragma handlers
ASTContext Context(OpenCLLangOpts, SourceMgr,
PP.getIdentifierTable(), PP.getSelectorTable(),
PP.getBuiltinInfo());
Context.InitBuiltinTypes(*Target);
ASTConsumer Consumer;
Sema S(PP, Context, Consumer);
Parser P(PP, S, false);
PragmaOpenCLExtensionCallbacks* Callbacks = new PragmaOpenCLExtensionCallbacks;
PP.addPPCallbacks(std::unique_ptr<PPCallbacks>(Callbacks));
// Lex source text.
PP.EnterMainSourceFile();
while (true) {
Token Tok;
PP.Lex(Tok);
if (Tok.is(tok::eof))
break;
}
PragmaOpenCLExtensionCallbacks::CallbackParameters RetVal = {
Callbacks->Name,
Callbacks->State
};
return RetVal;
}
};
TEST_F(PPCallbacksTest, QuotedFilename) {
const char* Source =
"#include \"quoted.h\"\n";
CharSourceRange Range =
InclusionDirectiveFilenameRange(Source, "/quoted.h", false);
ASSERT_EQ("\"quoted.h\"", GetSourceString(Range));
}
TEST_F(PPCallbacksTest, AngledFilename) {
const char* Source =
"#include <angled.h>\n";
CharSourceRange Range =
InclusionDirectiveFilenameRange(Source, "/angled.h", true);
ASSERT_EQ("<angled.h>", GetSourceString(Range));
}
TEST_F(PPCallbacksTest, QuotedInMacro) {
const char* Source =
"#define MACRO_QUOTED \"quoted.h\"\n"
"#include MACRO_QUOTED\n";
CharSourceRange Range =
InclusionDirectiveFilenameRange(Source, "/quoted.h", false);
ASSERT_EQ("\"quoted.h\"", GetSourceString(Range));
}
TEST_F(PPCallbacksTest, AngledInMacro) {
const char* Source =
"#define MACRO_ANGLED <angled.h>\n"
"#include MACRO_ANGLED\n";
CharSourceRange Range =
InclusionDirectiveFilenameRange(Source, "/angled.h", true);
ASSERT_EQ("<angled.h>", GetSourceString(Range));
}
TEST_F(PPCallbacksTest, StringizedMacroArgument) {
const char* Source =
"#define MACRO_STRINGIZED(x) #x\n"
"#include MACRO_STRINGIZED(quoted.h)\n";
CharSourceRange Range =
InclusionDirectiveFilenameRange(Source, "/quoted.h", false);
ASSERT_EQ("\"quoted.h\"", GetSourceString(Range));
}
TEST_F(PPCallbacksTest, ConcatenatedMacroArgument) {
const char* Source =
"#define MACRO_ANGLED <angled.h>\n"
"#define MACRO_CONCAT(x, y) x ## _ ## y\n"
"#include MACRO_CONCAT(MACRO, ANGLED)\n";
CharSourceRange Range =
InclusionDirectiveFilenameRange(Source, "/angled.h", false);
ASSERT_EQ("<angled.h>", GetSourceString(Range));
}
TEST_F(PPCallbacksTest, TrigraphFilename) {
const char* Source =
"#include \"tri\?\?-graph.h\"\n";
CharSourceRange Range =
InclusionDirectiveFilenameRange(Source, "/tri~graph.h", false);
ASSERT_EQ("\"tri\?\?-graph.h\"", GetSourceString(Range));
}
TEST_F(PPCallbacksTest, TrigraphInMacro) {
const char* Source =
"#define MACRO_TRIGRAPH \"tri\?\?-graph.h\"\n"
"#include MACRO_TRIGRAPH\n";
CharSourceRange Range =
InclusionDirectiveFilenameRange(Source, "/tri~graph.h", false);
ASSERT_EQ("\"tri\?\?-graph.h\"", GetSourceString(Range));
}
TEST_F(PPCallbacksTest, OpenCLExtensionPragmaEnabled) {
const char* Source =
"#pragma OPENCL EXTENSION cl_khr_fp64 : enable\n";
PragmaOpenCLExtensionCallbacks::CallbackParameters Parameters =
PragmaOpenCLExtensionCall(Source);
ASSERT_EQ("cl_khr_fp64", Parameters.Name);
unsigned ExpectedState = 1;
ASSERT_EQ(ExpectedState, Parameters.State);
}
TEST_F(PPCallbacksTest, OpenCLExtensionPragmaDisabled) {
const char* Source =
"#pragma OPENCL EXTENSION cl_khr_fp16 : disable\n";
PragmaOpenCLExtensionCallbacks::CallbackParameters Parameters =
PragmaOpenCLExtensionCall(Source);
ASSERT_EQ("cl_khr_fp16", Parameters.Name);
unsigned ExpectedState = 0;
ASSERT_EQ(ExpectedState, Parameters.State);
}
} // anonoymous namespace