llvm-project/clang-tools-extra/clangd/index/FileIndex.cpp

435 lines
15 KiB
C++

//===--- FileIndex.cpp - Indexes for files. ------------------------ C++-*-===//
//
// 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 "FileIndex.h"
#include "CollectMacros.h"
#include "ParsedAST.h"
#include "SymbolCollector.h"
#include "index/CanonicalIncludes.h"
#include "index/Index.h"
#include "index/MemIndex.h"
#include "index/Merge.h"
#include "index/Ref.h"
#include "index/Relation.h"
#include "index/Serialization.h"
#include "index/Symbol.h"
#include "index/SymbolID.h"
#include "index/SymbolOrigin.h"
#include "index/dex/Dex.h"
#include "support/Logger.h"
#include "support/Path.h"
#include "clang/AST/ASTContext.h"
#include "clang/Index/IndexingAction.h"
#include "clang/Index/IndexingOptions.h"
#include "clang/Lex/MacroInfo.h"
#include "clang/Lex/Preprocessor.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/Error.h"
#include <memory>
#include <tuple>
#include <utility>
#include <vector>
namespace clang {
namespace clangd {
namespace {
SlabTuple indexSymbols(ASTContext &AST, std::shared_ptr<Preprocessor> PP,
llvm::ArrayRef<Decl *> DeclsToIndex,
const MainFileMacros *MacroRefsToIndex,
const CanonicalIncludes &Includes, bool IsIndexMainAST,
llvm::StringRef Version) {
SymbolCollector::Options CollectorOpts;
CollectorOpts.CollectIncludePath = true;
CollectorOpts.Includes = &Includes;
CollectorOpts.CountReferences = false;
CollectorOpts.Origin = SymbolOrigin::Dynamic;
index::IndexingOptions IndexOpts;
// We only need declarations, because we don't count references.
IndexOpts.SystemSymbolFilter =
index::IndexingOptions::SystemSymbolFilterKind::DeclarationsOnly;
IndexOpts.IndexFunctionLocals = false;
if (IsIndexMainAST) {
// We only collect refs when indexing main AST.
CollectorOpts.RefFilter = RefKind::All;
// Comments for main file can always be obtained from sema, do not store
// them in the index.
CollectorOpts.StoreAllDocumentation = false;
} else {
IndexOpts.IndexMacrosInPreprocessor = true;
CollectorOpts.CollectMacro = true;
CollectorOpts.StoreAllDocumentation = true;
}
SymbolCollector Collector(std::move(CollectorOpts));
Collector.setPreprocessor(PP);
if (MacroRefsToIndex)
Collector.handleMacros(*MacroRefsToIndex);
index::indexTopLevelDecls(AST, *PP, DeclsToIndex, Collector, IndexOpts);
const auto &SM = AST.getSourceManager();
const auto *MainFileEntry = SM.getFileEntryForID(SM.getMainFileID());
std::string FileName =
std::string(MainFileEntry ? MainFileEntry->getName() : "");
auto Syms = Collector.takeSymbols();
auto Refs = Collector.takeRefs();
auto Relations = Collector.takeRelations();
vlog("indexed {0} AST for {1} version {2}:\n"
" symbol slab: {3} symbols, {4} bytes\n"
" ref slab: {5} symbols, {6} refs, {7} bytes\n"
" relations slab: {8} relations, {9} bytes",
IsIndexMainAST ? "file" : "preamble", FileName, Version, Syms.size(),
Syms.bytes(), Refs.size(), Refs.numRefs(), Refs.bytes(),
Relations.size(), Relations.bytes());
return std::make_tuple(std::move(Syms), std::move(Refs),
std::move(Relations));
}
// Resolves URI to file paths with cache.
class URIToFileCache {
public:
URIToFileCache(PathRef HintPath) : HintPath(HintPath) {}
llvm::StringRef operator[](llvm::StringRef FileURI) {
if (FileURI.empty())
return "";
auto I = URIToPathCache.try_emplace(FileURI);
if (I.second) {
I.first->second = llvm::cantFail(URI::resolve(FileURI, HintPath),
"Failed to resolve URI");
}
return I.first->second;
}
private:
PathRef HintPath;
llvm::StringMap<std::string> URIToPathCache;
};
// We keep only the node "U" and its edges. Any node other than "U" will be
// empty in the resultant graph.
IncludeGraph getSubGraph(llvm::StringRef URI, const IncludeGraph &FullGraph) {
IncludeGraph IG;
auto Entry = IG.try_emplace(URI).first;
auto &Node = Entry->getValue();
Node = FullGraph.lookup(Entry->getKey());
Node.URI = Entry->getKey();
// URIs inside nodes must point into the keys of the same IncludeGraph.
for (auto &Include : Node.DirectIncludes) {
auto I = IG.try_emplace(Include).first;
I->getValue().URI = I->getKey();
Include = I->getKey();
}
return IG;
}
} // namespace
FileShardedIndex::FileShardedIndex(IndexFileIn Input, PathRef HintPath)
: Index(std::move(Input)) {
URIToFileCache UriToFile(HintPath);
// Used to build RelationSlabs.
llvm::DenseMap<SymbolID, FileShard *> SymbolIDToFile;
// Attribute each Symbol to both their declaration and definition locations.
if (Index.Symbols) {
for (const auto &S : *Index.Symbols) {
auto File = UriToFile[S.CanonicalDeclaration.FileURI];
auto It = Shards.try_emplace(File);
It.first->getValue().Symbols.insert(&S);
SymbolIDToFile[S.ID] = &It.first->getValue();
// Only bother if definition file is different than declaration file.
if (S.Definition &&
S.Definition.FileURI != S.CanonicalDeclaration.FileURI) {
auto File = UriToFile[S.Definition.FileURI];
auto It = Shards.try_emplace(File);
It.first->getValue().Symbols.insert(&S);
}
}
}
// Attribute references into each file they occured in.
if (Index.Refs) {
for (const auto &SymRefs : *Index.Refs) {
for (const auto &R : SymRefs.second) {
auto File = UriToFile[R.Location.FileURI];
const auto It = Shards.try_emplace(File);
It.first->getValue().Refs.insert(&R);
RefToSymID[&R] = SymRefs.first;
}
}
}
// Attribute relations to the file declaraing their Subject as Object might
// not have been indexed, see SymbolCollector::processRelations for details.
if (Index.Relations) {
for (const auto &R : *Index.Relations) {
// FIXME: RelationSlab shouldn't contain dangling relations.
if (auto *File = SymbolIDToFile.lookup(R.Subject))
File->Relations.insert(&R);
}
}
// Store only the direct includes of a file in a shard.
if (Index.Sources) {
const auto &FullGraph = *Index.Sources;
for (const auto &It : FullGraph) {
auto File = UriToFile[It.first()];
auto ShardIt = Shards.try_emplace(File);
ShardIt.first->getValue().IG = getSubGraph(It.first(), FullGraph);
}
}
}
std::vector<PathRef> FileShardedIndex::getAllFiles() const {
// It should be enough to construct a vector with {Shards.keys().begin(),
// Shards.keys().end()} but MSVC fails to compile that.
std::vector<PathRef> Result;
Result.reserve(Shards.size());
for (PathRef Key : Shards.keys())
Result.push_back(Key);
return Result;
}
IndexFileIn FileShardedIndex::getShard(PathRef File) const {
auto It = Shards.find(File);
assert(It != Shards.end() && "received unknown file");
IndexFileIn IF;
IF.Sources = It->getValue().IG;
IF.Cmd = Index.Cmd;
SymbolSlab::Builder SymB;
for (const auto *S : It->getValue().Symbols)
SymB.insert(*S);
IF.Symbols = std::move(SymB).build();
RefSlab::Builder RefB;
for (const auto *Ref : It->getValue().Refs) {
auto SID = RefToSymID.lookup(Ref);
RefB.insert(SID, *Ref);
}
IF.Refs = std::move(RefB).build();
RelationSlab::Builder RelB;
for (const auto *Rel : It->getValue().Relations) {
RelB.insert(*Rel);
}
IF.Relations = std::move(RelB).build();
return IF;
}
SlabTuple indexMainDecls(ParsedAST &AST) {
return indexSymbols(AST.getASTContext(), AST.getPreprocessorPtr(),
AST.getLocalTopLevelDecls(), &AST.getMacros(),
AST.getCanonicalIncludes(),
/*IsIndexMainAST=*/true, AST.version());
}
SlabTuple indexHeaderSymbols(llvm::StringRef Version, ASTContext &AST,
std::shared_ptr<Preprocessor> PP,
const CanonicalIncludes &Includes) {
std::vector<Decl *> DeclsToIndex(
AST.getTranslationUnitDecl()->decls().begin(),
AST.getTranslationUnitDecl()->decls().end());
return indexSymbols(AST, std::move(PP), DeclsToIndex,
/*MainFileMacros=*/nullptr, Includes,
/*IsIndexMainAST=*/false, Version);
}
void FileSymbols::update(PathRef Path, std::unique_ptr<SymbolSlab> Symbols,
std::unique_ptr<RefSlab> Refs,
std::unique_ptr<RelationSlab> Relations,
bool CountReferences) {
std::lock_guard<std::mutex> Lock(Mutex);
if (!Symbols)
FileToSymbols.erase(Path);
else
FileToSymbols[Path] = std::move(Symbols);
if (!Refs) {
FileToRefs.erase(Path);
} else {
RefSlabAndCountReferences Item;
Item.CountReferences = CountReferences;
Item.Slab = std::move(Refs);
FileToRefs[Path] = std::move(Item);
}
if (!Relations)
FileToRelations.erase(Path);
else
FileToRelations[Path] = std::move(Relations);
}
std::unique_ptr<SymbolIndex>
FileSymbols::buildIndex(IndexType Type, DuplicateHandling DuplicateHandle) {
std::vector<std::shared_ptr<SymbolSlab>> SymbolSlabs;
std::vector<std::shared_ptr<RefSlab>> RefSlabs;
std::vector<std::shared_ptr<RelationSlab>> RelationSlabs;
std::vector<RefSlab *> MainFileRefs;
{
std::lock_guard<std::mutex> Lock(Mutex);
for (const auto &FileAndSymbols : FileToSymbols)
SymbolSlabs.push_back(FileAndSymbols.second);
for (const auto &FileAndRefs : FileToRefs) {
RefSlabs.push_back(FileAndRefs.second.Slab);
if (FileAndRefs.second.CountReferences)
MainFileRefs.push_back(RefSlabs.back().get());
}
for (const auto &FileAndRelations : FileToRelations)
RelationSlabs.push_back(FileAndRelations.second);
}
std::vector<const Symbol *> AllSymbols;
std::vector<Symbol> SymsStorage;
switch (DuplicateHandle) {
case DuplicateHandling::Merge: {
llvm::DenseMap<SymbolID, Symbol> Merged;
for (const auto &Slab : SymbolSlabs) {
for (const auto &Sym : *Slab) {
assert(Sym.References == 0 &&
"Symbol with non-zero references sent to FileSymbols");
auto I = Merged.try_emplace(Sym.ID, Sym);
if (!I.second)
I.first->second = mergeSymbol(I.first->second, Sym);
}
}
for (const RefSlab *Refs : MainFileRefs)
for (const auto &Sym : *Refs) {
auto It = Merged.find(Sym.first);
// This might happen while background-index is still running.
if (It == Merged.end())
continue;
It->getSecond().References += Sym.second.size();
}
SymsStorage.reserve(Merged.size());
for (auto &Sym : Merged) {
SymsStorage.push_back(std::move(Sym.second));
AllSymbols.push_back(&SymsStorage.back());
}
break;
}
case DuplicateHandling::PickOne: {
llvm::DenseSet<SymbolID> AddedSymbols;
for (const auto &Slab : SymbolSlabs)
for (const auto &Sym : *Slab) {
assert(Sym.References == 0 &&
"Symbol with non-zero references sent to FileSymbols");
if (AddedSymbols.insert(Sym.ID).second)
AllSymbols.push_back(&Sym);
}
break;
}
}
std::vector<Ref> RefsStorage; // Contiguous ranges for each SymbolID.
llvm::DenseMap<SymbolID, llvm::ArrayRef<Ref>> AllRefs;
{
llvm::DenseMap<SymbolID, llvm::SmallVector<Ref, 4>> MergedRefs;
size_t Count = 0;
for (const auto &RefSlab : RefSlabs)
for (const auto &Sym : *RefSlab) {
MergedRefs[Sym.first].append(Sym.second.begin(), Sym.second.end());
Count += Sym.second.size();
}
RefsStorage.reserve(Count);
AllRefs.reserve(MergedRefs.size());
for (auto &Sym : MergedRefs) {
auto &SymRefs = Sym.second;
// Sorting isn't required, but yields more stable results over rebuilds.
llvm::sort(SymRefs);
llvm::copy(SymRefs, back_inserter(RefsStorage));
AllRefs.try_emplace(
Sym.first,
llvm::ArrayRef<Ref>(&RefsStorage[RefsStorage.size() - SymRefs.size()],
SymRefs.size()));
}
}
std::vector<Relation> AllRelations;
for (const auto &RelationSlab : RelationSlabs) {
for (const auto &R : *RelationSlab)
AllRelations.push_back(R);
}
size_t StorageSize =
RefsStorage.size() * sizeof(Ref) + SymsStorage.size() * sizeof(Symbol);
for (const auto &Slab : SymbolSlabs)
StorageSize += Slab->bytes();
for (const auto &RefSlab : RefSlabs)
StorageSize += RefSlab->bytes();
for (const auto &RelationSlab : RelationSlabs)
StorageSize += RelationSlab->bytes();
// Index must keep the slabs and contiguous ranges alive.
switch (Type) {
case IndexType::Light:
return std::make_unique<MemIndex>(
llvm::make_pointee_range(AllSymbols), std::move(AllRefs),
std::move(AllRelations),
std::make_tuple(std::move(SymbolSlabs), std::move(RefSlabs),
std::move(RefsStorage), std::move(SymsStorage)),
StorageSize);
case IndexType::Heavy:
return std::make_unique<dex::Dex>(
llvm::make_pointee_range(AllSymbols), std::move(AllRefs),
std::move(AllRelations),
std::make_tuple(std::move(SymbolSlabs), std::move(RefSlabs),
std::move(RefsStorage), std::move(SymsStorage)),
StorageSize);
}
llvm_unreachable("Unknown clangd::IndexType");
}
FileIndex::FileIndex(bool UseDex)
: MergedIndex(&MainFileIndex, &PreambleIndex), UseDex(UseDex),
PreambleIndex(std::make_unique<MemIndex>()),
MainFileIndex(std::make_unique<MemIndex>()) {}
void FileIndex::updatePreamble(PathRef Path, llvm::StringRef Version,
ASTContext &AST,
std::shared_ptr<Preprocessor> PP,
const CanonicalIncludes &Includes) {
IndexFileIn IF;
std::tie(IF.Symbols, std::ignore, IF.Relations) =
indexHeaderSymbols(Version, AST, std::move(PP), Includes);
FileShardedIndex ShardedIndex(std::move(IF), Path);
for (PathRef File : ShardedIndex.getAllFiles()) {
auto IF = ShardedIndex.getShard(File);
PreambleSymbols.update(
File, std::make_unique<SymbolSlab>(std::move(*IF.Symbols)),
std::make_unique<RefSlab>(),
std::make_unique<RelationSlab>(std::move(*IF.Relations)),
/*CountReferences=*/false);
}
PreambleIndex.reset(
PreambleSymbols.buildIndex(UseDex ? IndexType::Heavy : IndexType::Light,
DuplicateHandling::PickOne));
vlog("Build dynamic index for header symbols with estimated memory usage of "
"{0} bytes",
PreambleIndex.estimateMemoryUsage());
}
void FileIndex::updateMain(PathRef Path, ParsedAST &AST) {
auto Contents = indexMainDecls(AST);
MainFileSymbols.update(
Path, std::make_unique<SymbolSlab>(std::move(std::get<0>(Contents))),
std::make_unique<RefSlab>(std::move(std::get<1>(Contents))),
std::make_unique<RelationSlab>(std::move(std::get<2>(Contents))),
/*CountReferences=*/true);
MainFileIndex.reset(
MainFileSymbols.buildIndex(IndexType::Light, DuplicateHandling::Merge));
vlog("Build dynamic index for main-file symbols with estimated memory usage "
"of {0} bytes",
MainFileIndex.estimateMemoryUsage());
}
} // namespace clangd
} // namespace clang