llvm-project/clang-tools-extra/clangd/XRefs.cpp

1322 lines
46 KiB
C++

//===--- XRefs.cpp -----------------------------------------------*- 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 "XRefs.h"
#include "AST.h"
#include "CodeCompletionStrings.h"
#include "FindSymbols.h"
#include "FindTarget.h"
#include "FormattedString.h"
#include "Logger.h"
#include "ParsedAST.h"
#include "Protocol.h"
#include "SourceCode.h"
#include "URI.h"
#include "index/Index.h"
#include "index/Merge.h"
#include "index/Relation.h"
#include "index/SymbolCollector.h"
#include "index/SymbolLocation.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/PrettyPrinter.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/AST/Type.h"
#include "clang/Basic/LLVM.h"
#include "clang/Basic/SourceLocation.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Index/IndexDataConsumer.h"
#include "clang/Index/IndexSymbol.h"
#include "clang/Index/IndexingAction.h"
#include "clang/Index/IndexingOptions.h"
#include "clang/Index/USRGeneration.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/None.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/raw_ostream.h"
namespace clang {
namespace clangd {
namespace {
// Returns the single definition of the entity declared by D, if visible.
// In particular:
// - for non-redeclarable kinds (e.g. local vars), return D
// - for kinds that allow multiple definitions (e.g. namespaces), return nullptr
// Kinds of nodes that always return nullptr here will not have definitions
// reported by locateSymbolAt().
const Decl *getDefinition(const Decl *D) {
assert(D);
// Decl has one definition that we can find.
if (const auto *TD = dyn_cast<TagDecl>(D))
return TD->getDefinition();
if (const auto *VD = dyn_cast<VarDecl>(D))
return VD->getDefinition();
if (const auto *FD = dyn_cast<FunctionDecl>(D))
return FD->getDefinition();
// Only a single declaration is allowed.
if (isa<ValueDecl>(D) || isa<TemplateTypeParmDecl>(D) ||
isa<TemplateTemplateParmDecl>(D)) // except cases above
return D;
// Multiple definitions are allowed.
return nullptr; // except cases above
}
void logIfOverflow(const SymbolLocation &Loc) {
if (Loc.Start.hasOverflow() || Loc.End.hasOverflow())
log("Possible overflow in symbol location: {0}", Loc);
}
// Convert a SymbolLocation to LSP's Location.
// TUPath is used to resolve the path of URI.
// FIXME: figure out a good home for it, and share the implementation with
// FindSymbols.
llvm::Optional<Location> toLSPLocation(const SymbolLocation &Loc,
llvm::StringRef TUPath) {
if (!Loc)
return None;
auto Uri = URI::parse(Loc.FileURI);
if (!Uri) {
elog("Could not parse URI {0}: {1}", Loc.FileURI, Uri.takeError());
return None;
}
auto U = URIForFile::fromURI(*Uri, TUPath);
if (!U) {
elog("Could not resolve URI {0}: {1}", Loc.FileURI, U.takeError());
return None;
}
Location LSPLoc;
LSPLoc.uri = std::move(*U);
LSPLoc.range.start.line = Loc.Start.line();
LSPLoc.range.start.character = Loc.Start.column();
LSPLoc.range.end.line = Loc.End.line();
LSPLoc.range.end.character = Loc.End.column();
logIfOverflow(Loc);
return LSPLoc;
}
SymbolLocation toIndexLocation(const Location &Loc, std::string &URIStorage) {
SymbolLocation SymLoc;
URIStorage = Loc.uri.uri();
SymLoc.FileURI = URIStorage.c_str();
SymLoc.Start.setLine(Loc.range.start.line);
SymLoc.Start.setColumn(Loc.range.start.character);
SymLoc.End.setLine(Loc.range.end.line);
SymLoc.End.setColumn(Loc.range.end.character);
return SymLoc;
}
// Returns the preferred location between an AST location and an index location.
SymbolLocation getPreferredLocation(const Location &ASTLoc,
const SymbolLocation &IdxLoc,
std::string &Scratch) {
// Also use a dummy symbol for the index location so that other fields (e.g.
// definition) are not factored into the preferrence.
Symbol ASTSym, IdxSym;
ASTSym.ID = IdxSym.ID = SymbolID("dummy_id");
ASTSym.CanonicalDeclaration = toIndexLocation(ASTLoc, Scratch);
IdxSym.CanonicalDeclaration = IdxLoc;
auto Merged = mergeSymbol(ASTSym, IdxSym);
return Merged.CanonicalDeclaration;
}
/// Finds declarations locations that a given source location refers to.
class DeclarationFinder : public index::IndexDataConsumer {
llvm::DenseSet<const Decl *> Decls;
const SourceLocation &SearchedLocation;
public:
DeclarationFinder(const SourceLocation &SearchedLocation)
: SearchedLocation(SearchedLocation) {}
// The results are sorted by declaration location.
std::vector<const Decl *> getFoundDecls() const {
std::vector<const Decl *> Result;
for (const Decl *D : Decls)
Result.push_back(D);
llvm::sort(Result, [](const Decl *L, const Decl *R) {
return L->getBeginLoc() < R->getBeginLoc();
});
return Result;
}
bool
handleDeclOccurence(const Decl *D, index::SymbolRoleSet Roles,
llvm::ArrayRef<index::SymbolRelation> Relations,
SourceLocation Loc,
index::IndexDataConsumer::ASTNodeInfo ASTNode) override {
// Skip non-semantic references.
if (Roles & static_cast<unsigned>(index::SymbolRole::NameReference))
return true;
if (Loc == SearchedLocation) {
auto IsImplicitExpr = [](const Expr *E) {
if (!E)
return false;
// We assume that a constructor expression is implict (was inserted by
// clang) if it has an invalid paren/brace location, since such
// experssion is impossible to write down.
if (const auto *CtorExpr = dyn_cast<CXXConstructExpr>(E))
return CtorExpr->getParenOrBraceRange().isInvalid();
// Ignore implicit conversion-operator AST node.
if (const auto *ME = dyn_cast<MemberExpr>(E)) {
if (isa<CXXConversionDecl>(ME->getMemberDecl()))
return ME->getMemberLoc().isInvalid();
}
return isa<ImplicitCastExpr>(E);
};
if (IsImplicitExpr(ASTNode.OrigE))
return true;
// Find and add definition declarations (for GoToDefinition).
// We don't use parameter `D`, as Parameter `D` is the canonical
// declaration, which is the first declaration of a redeclarable
// declaration, and it could be a forward declaration.
if (const auto *Def = getDefinition(D)) {
Decls.insert(Def);
} else {
// Couldn't find a definition, fall back to use `D`.
Decls.insert(D);
}
}
return true;
}
};
std::vector<const Decl *> getDeclAtPosition(ParsedAST &AST,
SourceLocation Pos) {
DeclarationFinder Finder(Pos);
index::IndexingOptions IndexOpts;
IndexOpts.SystemSymbolFilter =
index::IndexingOptions::SystemSymbolFilterKind::All;
IndexOpts.IndexFunctionLocals = true;
IndexOpts.IndexParametersInDeclarations = true;
IndexOpts.IndexTemplateParameters = true;
indexTopLevelDecls(AST.getASTContext(), AST.getPreprocessor(),
AST.getLocalTopLevelDecls(), Finder, IndexOpts);
return Finder.getFoundDecls();
}
llvm::Optional<Location> makeLocation(ASTContext &AST, SourceLocation TokLoc,
llvm::StringRef TUPath) {
const SourceManager &SourceMgr = AST.getSourceManager();
const FileEntry *F = SourceMgr.getFileEntryForID(SourceMgr.getFileID(TokLoc));
if (!F)
return None;
auto FilePath = getCanonicalPath(F, SourceMgr);
if (!FilePath) {
log("failed to get path!");
return None;
}
if (auto Range =
getTokenRange(AST.getSourceManager(), AST.getLangOpts(), TokLoc)) {
Location L;
L.uri = URIForFile::canonicalize(*FilePath, TUPath);
L.range = *Range;
return L;
}
return None;
}
} // namespace
std::vector<LocatedSymbol> locateSymbolAt(ParsedAST &AST, Position Pos,
const SymbolIndex *Index) {
const auto &SM = AST.getSourceManager();
auto MainFilePath =
getCanonicalPath(SM.getFileEntryForID(SM.getMainFileID()), SM);
if (!MainFilePath) {
elog("Failed to get a path for the main file, so no references");
return {};
}
// Treat #included files as symbols, to enable go-to-definition on them.
for (auto &Inc : AST.getIncludeStructure().MainFileIncludes) {
if (!Inc.Resolved.empty() && Inc.R.start.line == Pos.line) {
LocatedSymbol File;
File.Name = llvm::sys::path::filename(Inc.Resolved);
File.PreferredDeclaration = {
URIForFile::canonicalize(Inc.Resolved, *MainFilePath), Range{}};
File.Definition = File.PreferredDeclaration;
// We're not going to find any further symbols on #include lines.
return {std::move(File)};
}
}
SourceLocation SourceLocationBeg =
SM.getMacroArgExpandedLocation(getBeginningOfIdentifier(
Pos, AST.getSourceManager(), AST.getASTContext().getLangOpts()));
// Macros are simple: there's no declaration/definition distinction.
// As a consequence, there's no need to look them up in the index either.
std::vector<LocatedSymbol> Result;
if (auto M = locateMacroAt(SourceLocationBeg, AST.getPreprocessor())) {
if (auto Loc = makeLocation(AST.getASTContext(),
M->Info->getDefinitionLoc(), *MainFilePath)) {
LocatedSymbol Macro;
Macro.Name = M->Name;
Macro.PreferredDeclaration = *Loc;
Macro.Definition = Loc;
Result.push_back(std::move(Macro));
}
}
// Decls are more complicated.
// The AST contains at least a declaration, maybe a definition.
// These are up-to-date, and so generally preferred over index results.
// We perform a single batch index lookup to find additional definitions.
// Results follow the order of Symbols.Decls.
// Keep track of SymbolID -> index mapping, to fill in index data later.
llvm::DenseMap<SymbolID, size_t> ResultIndex;
// Emit all symbol locations (declaration or definition) from AST.
for (const Decl *D : getDeclAtPosition(AST, SourceLocationBeg)) {
auto Loc =
makeLocation(AST.getASTContext(), spellingLocIfSpelled(findName(D), SM),
*MainFilePath);
if (!Loc)
continue;
Result.emplace_back();
if (auto *ND = dyn_cast<NamedDecl>(D))
Result.back().Name = printName(AST.getASTContext(), *ND);
Result.back().PreferredDeclaration = *Loc;
// DeclInfo.D is always a definition if possible, so this check works.
if (getDefinition(D) == D)
Result.back().Definition = *Loc;
// Record SymbolID for index lookup later.
if (auto ID = getSymbolID(D))
ResultIndex[*ID] = Result.size() - 1;
}
// Now query the index for all Symbol IDs we found in the AST.
if (Index && !ResultIndex.empty()) {
LookupRequest QueryRequest;
for (auto It : ResultIndex)
QueryRequest.IDs.insert(It.first);
std::string Scratch;
Index->lookup(QueryRequest, [&](const Symbol &Sym) {
auto &R = Result[ResultIndex.lookup(Sym.ID)];
if (R.Definition) { // from AST
// Special case: if the AST yielded a definition, then it may not be
// the right *declaration*. Prefer the one from the index.
if (auto Loc = toLSPLocation(Sym.CanonicalDeclaration, *MainFilePath))
R.PreferredDeclaration = *Loc;
// We might still prefer the definition from the index, e.g. for
// generated symbols.
if (auto Loc = toLSPLocation(
getPreferredLocation(*R.Definition, Sym.Definition, Scratch),
*MainFilePath))
R.Definition = *Loc;
} else {
R.Definition = toLSPLocation(Sym.Definition, *MainFilePath);
// Use merge logic to choose AST or index declaration.
if (auto Loc = toLSPLocation(
getPreferredLocation(R.PreferredDeclaration,
Sym.CanonicalDeclaration, Scratch),
*MainFilePath))
R.PreferredDeclaration = *Loc;
}
});
}
return Result;
}
namespace {
/// Collects references to symbols within the main file.
class ReferenceFinder : public index::IndexDataConsumer {
public:
struct Reference {
SourceLocation Loc;
index::SymbolRoleSet Role;
};
ReferenceFinder(ASTContext &AST, Preprocessor &PP,
const std::vector<const Decl *> &TargetDecls)
: AST(AST) {
for (const Decl *D : TargetDecls)
CanonicalTargets.insert(D->getCanonicalDecl());
}
std::vector<Reference> take() && {
llvm::sort(References, [](const Reference &L, const Reference &R) {
return std::tie(L.Loc, L.Role) < std::tie(R.Loc, R.Role);
});
// We sometimes see duplicates when parts of the AST get traversed twice.
References.erase(std::unique(References.begin(), References.end(),
[](const Reference &L, const Reference &R) {
return std::tie(L.Loc, L.Role) ==
std::tie(R.Loc, R.Role);
}),
References.end());
return std::move(References);
}
bool
handleDeclOccurence(const Decl *D, index::SymbolRoleSet Roles,
llvm::ArrayRef<index::SymbolRelation> Relations,
SourceLocation Loc,
index::IndexDataConsumer::ASTNodeInfo ASTNode) override {
assert(D->isCanonicalDecl() && "expect D to be a canonical declaration");
const SourceManager &SM = AST.getSourceManager();
Loc = SM.getFileLoc(Loc);
if (isInsideMainFile(Loc, SM) && CanonicalTargets.count(D))
References.push_back({Loc, Roles});
return true;
}
private:
llvm::SmallSet<const Decl *, 4> CanonicalTargets;
std::vector<Reference> References;
const ASTContext &AST;
};
std::vector<ReferenceFinder::Reference>
findRefs(const std::vector<const Decl *> &Decls, ParsedAST &AST) {
ReferenceFinder RefFinder(AST.getASTContext(), AST.getPreprocessor(), Decls);
index::IndexingOptions IndexOpts;
IndexOpts.SystemSymbolFilter =
index::IndexingOptions::SystemSymbolFilterKind::All;
IndexOpts.IndexFunctionLocals = true;
IndexOpts.IndexParametersInDeclarations = true;
IndexOpts.IndexTemplateParameters = true;
indexTopLevelDecls(AST.getASTContext(), AST.getPreprocessor(),
AST.getLocalTopLevelDecls(), RefFinder, IndexOpts);
return std::move(RefFinder).take();
}
} // namespace
std::vector<DocumentHighlight> findDocumentHighlights(ParsedAST &AST,
Position Pos) {
const SourceManager &SM = AST.getSourceManager();
// FIXME: show references to macro within file?
auto References =
findRefs(getDeclAtPosition(
AST, SM.getMacroArgExpandedLocation(getBeginningOfIdentifier(
Pos, SM, AST.getASTContext().getLangOpts()))),
AST);
// FIXME: we may get multiple DocumentHighlights with the same location and
// different kinds, deduplicate them.
std::vector<DocumentHighlight> Result;
for (const auto &Ref : References) {
if (auto Range =
getTokenRange(AST.getASTContext().getSourceManager(),
AST.getASTContext().getLangOpts(), Ref.Loc)) {
DocumentHighlight DH;
DH.range = *Range;
if (Ref.Role & index::SymbolRoleSet(index::SymbolRole::Write))
DH.kind = DocumentHighlightKind::Write;
else if (Ref.Role & index::SymbolRoleSet(index::SymbolRole::Read))
DH.kind = DocumentHighlightKind::Read;
else
DH.kind = DocumentHighlightKind::Text;
Result.push_back(std::move(DH));
}
}
return Result;
}
static PrintingPolicy printingPolicyForDecls(PrintingPolicy Base) {
PrintingPolicy Policy(Base);
Policy.AnonymousTagLocations = false;
Policy.TerseOutput = true;
Policy.PolishForDeclaration = true;
Policy.ConstantsAsWritten = true;
Policy.SuppressTagKeyword = false;
return Policy;
}
/// Given a declaration \p D, return a human-readable string representing the
/// local scope in which it is declared, i.e. class(es) and method name. Returns
/// an empty string if it is not local.
static std::string getLocalScope(const Decl *D) {
std::vector<std::string> Scopes;
const DeclContext *DC = D->getDeclContext();
auto GetName = [](const Decl *D) {
const NamedDecl *ND = dyn_cast<NamedDecl>(D);
std::string Name = ND->getNameAsString();
if (!Name.empty())
return Name;
if (auto RD = dyn_cast<RecordDecl>(D))
return ("(anonymous " + RD->getKindName() + ")").str();
return std::string("");
};
while (DC) {
if (const TypeDecl *TD = dyn_cast<TypeDecl>(DC))
Scopes.push_back(GetName(TD));
else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(DC))
Scopes.push_back(FD->getNameAsString());
DC = DC->getParent();
}
return llvm::join(llvm::reverse(Scopes), "::");
}
/// Returns the human-readable representation for namespace containing the
/// declaration \p D. Returns empty if it is contained global namespace.
static std::string getNamespaceScope(const Decl *D) {
const DeclContext *DC = D->getDeclContext();
if (const TypeDecl *TD = dyn_cast<TypeDecl>(DC))
return getNamespaceScope(TD);
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(DC))
return getNamespaceScope(FD);
if (const NamedDecl *ND = dyn_cast<NamedDecl>(DC))
return ND->getQualifiedNameAsString();
return "";
}
static std::string printDefinition(const Decl *D) {
std::string Definition;
llvm::raw_string_ostream OS(Definition);
PrintingPolicy Policy =
printingPolicyForDecls(D->getASTContext().getPrintingPolicy());
Policy.IncludeTagDefinition = false;
D->print(OS, Policy);
OS.flush();
return Definition;
}
static void printParams(llvm::raw_ostream &OS,
const std::vector<HoverInfo::Param> &Params) {
for (size_t I = 0, E = Params.size(); I != E; ++I) {
if (I)
OS << ", ";
OS << Params.at(I);
}
}
static std::vector<HoverInfo::Param>
fetchTemplateParameters(const TemplateParameterList *Params,
const PrintingPolicy &PP) {
assert(Params);
std::vector<HoverInfo::Param> TempParameters;
for (const Decl *Param : *Params) {
HoverInfo::Param P;
P.Type.emplace();
if (const auto TTP = dyn_cast<TemplateTypeParmDecl>(Param)) {
P.Type = TTP->wasDeclaredWithTypename() ? "typename" : "class";
if (TTP->isParameterPack())
*P.Type += "...";
if (!TTP->getName().empty())
P.Name = TTP->getNameAsString();
if (TTP->hasDefaultArgument())
P.Default = TTP->getDefaultArgument().getAsString(PP);
} else if (const auto NTTP = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
if (IdentifierInfo *II = NTTP->getIdentifier())
P.Name = II->getName().str();
llvm::raw_string_ostream Out(*P.Type);
NTTP->getType().print(Out, PP);
if (NTTP->isParameterPack())
Out << "...";
if (NTTP->hasDefaultArgument()) {
P.Default.emplace();
llvm::raw_string_ostream Out(*P.Default);
NTTP->getDefaultArgument()->printPretty(Out, nullptr, PP);
}
} else if (const auto TTPD = dyn_cast<TemplateTemplateParmDecl>(Param)) {
llvm::raw_string_ostream OS(*P.Type);
OS << "template <";
printParams(OS,
fetchTemplateParameters(TTPD->getTemplateParameters(), PP));
OS << "> class"; // FIXME: TemplateTemplateParameter doesn't store the
// info on whether this param was a "typename" or
// "class".
if (!TTPD->getName().empty())
P.Name = TTPD->getNameAsString();
if (TTPD->hasDefaultArgument()) {
P.Default.emplace();
llvm::raw_string_ostream Out(*P.Default);
TTPD->getDefaultArgument().getArgument().print(PP, Out);
}
}
TempParameters.push_back(std::move(P));
}
return TempParameters;
}
static const FunctionDecl *getUnderlyingFunction(const Decl *D) {
// Extract lambda from variables.
if (const VarDecl *VD = llvm::dyn_cast<VarDecl>(D)) {
auto QT = VD->getType();
if (!QT.isNull()) {
while (!QT->getPointeeType().isNull())
QT = QT->getPointeeType();
if (const auto *CD = QT->getAsCXXRecordDecl())
return CD->getLambdaCallOperator();
}
}
// Non-lambda functions.
return D->getAsFunction();
}
// Look up information about D from the index, and add it to Hover.
static void enhanceFromIndex(HoverInfo &Hover, const Decl *D,
const SymbolIndex *Index) {
if (!Index || !llvm::isa<NamedDecl>(D))
return;
const NamedDecl &ND = *cast<NamedDecl>(D);
// We only add documentation, so don't bother if we already have some.
if (!Hover.Documentation.empty())
return;
// Skip querying for non-indexable symbols, there's no point.
// We're searching for symbols that might be indexed outside this main file.
if (!SymbolCollector::shouldCollectSymbol(ND, ND.getASTContext(),
SymbolCollector::Options(),
/*IsMainFileOnly=*/false))
return;
auto ID = getSymbolID(&ND);
if (!ID)
return;
LookupRequest Req;
Req.IDs.insert(*ID);
Index->lookup(
Req, [&](const Symbol &S) { Hover.Documentation = S.Documentation; });
}
/// Generate a \p Hover object given the declaration \p D.
static HoverInfo getHoverContents(const Decl *D, const SymbolIndex *Index) {
HoverInfo HI;
const ASTContext &Ctx = D->getASTContext();
HI.NamespaceScope = getNamespaceScope(D);
if (!HI.NamespaceScope->empty())
HI.NamespaceScope->append("::");
HI.LocalScope = getLocalScope(D);
if (!HI.LocalScope.empty())
HI.LocalScope.append("::");
PrintingPolicy Policy = printingPolicyForDecls(Ctx.getPrintingPolicy());
if (const NamedDecl *ND = llvm::dyn_cast<NamedDecl>(D)) {
HI.Documentation = getDeclComment(Ctx, *ND);
HI.Name = printName(Ctx, *ND);
}
HI.Kind = indexSymbolKindToSymbolKind(index::getSymbolInfo(D).Kind);
// Fill in template params.
if (const TemplateDecl *TD = D->getDescribedTemplate()) {
HI.TemplateParameters =
fetchTemplateParameters(TD->getTemplateParameters(), Policy);
D = TD;
} else if (const FunctionDecl *FD = D->getAsFunction()) {
if (const auto FTD = FD->getDescribedTemplate()) {
HI.TemplateParameters =
fetchTemplateParameters(FTD->getTemplateParameters(), Policy);
D = FTD;
}
}
// Fill in types and params.
if (const FunctionDecl *FD = getUnderlyingFunction(D)) {
HI.ReturnType.emplace();
{
llvm::raw_string_ostream OS(*HI.ReturnType);
FD->getReturnType().print(OS, Policy);
}
HI.Parameters.emplace();
for (const ParmVarDecl *PVD : FD->parameters()) {
HI.Parameters->emplace_back();
auto &P = HI.Parameters->back();
if (!PVD->getType().isNull()) {
P.Type.emplace();
llvm::raw_string_ostream OS(*P.Type);
PVD->getType().print(OS, Policy);
} else {
std::string Param;
llvm::raw_string_ostream OS(Param);
PVD->dump(OS);
OS.flush();
elog("Got param with null type: {0}", Param);
}
if (!PVD->getName().empty())
P.Name = PVD->getNameAsString();
if (PVD->hasDefaultArg()) {
P.Default.emplace();
llvm::raw_string_ostream Out(*P.Default);
PVD->getDefaultArg()->printPretty(Out, nullptr, Policy);
}
}
HI.Type.emplace();
llvm::raw_string_ostream TypeOS(*HI.Type);
// Lambdas
if (const VarDecl *VD = llvm::dyn_cast<VarDecl>(D))
VD->getType().getDesugaredType(D->getASTContext()).print(TypeOS, Policy);
// Functions
else
FD->getType().print(TypeOS, Policy);
// FIXME: handle variadics.
} else if (const auto *VD = dyn_cast<ValueDecl>(D)) {
HI.Type.emplace();
llvm::raw_string_ostream OS(*HI.Type);
VD->getType().print(OS, Policy);
}
// Fill in value with evaluated initializer if possible.
// FIXME(kadircet): Also set Value field for expressions like "sizeof" and
// function calls.
if (const auto *Var = dyn_cast<VarDecl>(D)) {
if (const Expr *Init = Var->getInit()) {
Expr::EvalResult Result;
if (!Init->isValueDependent() && Init->EvaluateAsRValue(Result, Ctx)) {
HI.Value.emplace();
llvm::raw_string_ostream ValueOS(*HI.Value);
Result.Val.printPretty(ValueOS, const_cast<ASTContext &>(Ctx),
Init->getType());
}
}
}
HI.Definition = printDefinition(D);
enhanceFromIndex(HI, D, Index);
return HI;
}
/// Generate a \p Hover object given the type \p T.
static HoverInfo getHoverContents(QualType T, const Decl *D, ASTContext &ASTCtx,
const SymbolIndex *Index) {
HoverInfo HI;
llvm::raw_string_ostream OS(HI.Name);
PrintingPolicy Policy = printingPolicyForDecls(ASTCtx.getPrintingPolicy());
T.print(OS, Policy);
OS.flush();
if (D) {
HI.Kind = indexSymbolKindToSymbolKind(index::getSymbolInfo(D).Kind);
enhanceFromIndex(HI, D, Index);
}
return HI;
}
/// Generate a \p Hover object given the macro \p MacroDecl.
static HoverInfo getHoverContents(const DefinedMacro &Macro, ParsedAST &AST) {
HoverInfo HI;
SourceManager &SM = AST.getSourceManager();
HI.Name = Macro.Name;
HI.Kind = indexSymbolKindToSymbolKind(
index::getSymbolInfoForMacro(*Macro.Info).Kind);
// FIXME: Populate documentation
// FIXME: Pupulate parameters
// Try to get the full definition, not just the name
SourceLocation StartLoc = Macro.Info->getDefinitionLoc();
SourceLocation EndLoc = Macro.Info->getDefinitionEndLoc();
if (EndLoc.isValid()) {
EndLoc = Lexer::getLocForEndOfToken(EndLoc, 0, SM,
AST.getASTContext().getLangOpts());
bool Invalid;
StringRef Buffer = SM.getBufferData(SM.getFileID(StartLoc), &Invalid);
if (!Invalid) {
unsigned StartOffset = SM.getFileOffset(StartLoc);
unsigned EndOffset = SM.getFileOffset(EndLoc);
if (EndOffset <= Buffer.size() && StartOffset < EndOffset)
HI.Definition =
("#define " + Buffer.substr(StartOffset, EndOffset - StartOffset))
.str();
}
}
return HI;
}
namespace {
/// Computes the deduced type at a given location by visiting the relevant
/// nodes. We use this to display the actual type when hovering over an "auto"
/// keyword or "decltype()" expression.
/// FIXME: This could have been a lot simpler by visiting AutoTypeLocs but it
/// seems that the AutoTypeLocs that can be visited along with their AutoType do
/// not have the deduced type set. Instead, we have to go to the appropriate
/// DeclaratorDecl/FunctionDecl and work our back to the AutoType that does have
/// a deduced type set. The AST should be improved to simplify this scenario.
class DeducedTypeVisitor : public RecursiveASTVisitor<DeducedTypeVisitor> {
SourceLocation SearchedLocation;
public:
DeducedTypeVisitor(SourceLocation SearchedLocation)
: SearchedLocation(SearchedLocation) {}
// Handle auto initializers:
//- auto i = 1;
//- decltype(auto) i = 1;
//- auto& i = 1;
//- auto* i = &a;
bool VisitDeclaratorDecl(DeclaratorDecl *D) {
if (!D->getTypeSourceInfo() ||
D->getTypeSourceInfo()->getTypeLoc().getBeginLoc() != SearchedLocation)
return true;
if (auto *AT = D->getType()->getContainedAutoType()) {
if (!AT->getDeducedType().isNull()) {
DeducedType = AT->getDeducedType();
this->D = D;
}
}
return true;
}
// Handle auto return types:
//- auto foo() {}
//- auto& foo() {}
//- auto foo() -> int {}
//- auto foo() -> decltype(1+1) {}
//- operator auto() const { return 10; }
bool VisitFunctionDecl(FunctionDecl *D) {
if (!D->getTypeSourceInfo())
return true;
// Loc of auto in return type (c++14).
auto CurLoc = D->getReturnTypeSourceRange().getBegin();
// Loc of "auto" in operator auto()
if (CurLoc.isInvalid() && dyn_cast<CXXConversionDecl>(D))
CurLoc = D->getTypeSourceInfo()->getTypeLoc().getBeginLoc();
// Loc of "auto" in function with traling return type (c++11).
if (CurLoc.isInvalid())
CurLoc = D->getSourceRange().getBegin();
if (CurLoc != SearchedLocation)
return true;
const AutoType *AT = D->getReturnType()->getContainedAutoType();
if (AT && !AT->getDeducedType().isNull()) {
DeducedType = AT->getDeducedType();
this->D = D;
} else if (auto DT = dyn_cast<DecltypeType>(D->getReturnType())) {
// auto in a trailing return type just points to a DecltypeType and
// getContainedAutoType does not unwrap it.
if (!DT->getUnderlyingType().isNull()) {
DeducedType = DT->getUnderlyingType();
this->D = D;
}
} else if (!D->getReturnType().isNull()) {
DeducedType = D->getReturnType();
this->D = D;
}
return true;
}
// Handle non-auto decltype, e.g.:
// - auto foo() -> decltype(expr) {}
// - decltype(expr);
bool VisitDecltypeTypeLoc(DecltypeTypeLoc TL) {
if (TL.getBeginLoc() != SearchedLocation)
return true;
// A DecltypeType's underlying type can be another DecltypeType! E.g.
// int I = 0;
// decltype(I) J = I;
// decltype(J) K = J;
const DecltypeType *DT = dyn_cast<DecltypeType>(TL.getTypePtr());
while (DT && !DT->getUnderlyingType().isNull()) {
DeducedType = DT->getUnderlyingType();
D = DT->getAsTagDecl();
DT = dyn_cast<DecltypeType>(DeducedType.getTypePtr());
}
return true;
}
QualType DeducedType;
const Decl *D = nullptr;
};
} // namespace
/// Retrieves the deduced type at a given location (auto, decltype).
/// SourceLocationBeg must point to the first character of the token
llvm::Optional<QualType> getDeducedType(ParsedAST &AST,
SourceLocation SourceLocationBeg) {
Token Tok;
auto &ASTCtx = AST.getASTContext();
// Only try to find a deduced type if the token is auto or decltype.
if (!SourceLocationBeg.isValid() ||
Lexer::getRawToken(SourceLocationBeg, Tok, ASTCtx.getSourceManager(),
ASTCtx.getLangOpts(), false) ||
!Tok.is(tok::raw_identifier)) {
return {};
}
AST.getPreprocessor().LookUpIdentifierInfo(Tok);
if (!(Tok.is(tok::kw_auto) || Tok.is(tok::kw_decltype)))
return {};
DeducedTypeVisitor V(SourceLocationBeg);
V.TraverseAST(AST.getASTContext());
return V.DeducedType;
}
/// Retrieves the deduced type at a given location (auto, decltype).
bool hasDeducedType(ParsedAST &AST, SourceLocation SourceLocationBeg) {
return (bool)getDeducedType(AST, SourceLocationBeg);
}
llvm::Optional<HoverInfo> getHover(ParsedAST &AST, Position Pos,
format::FormatStyle Style,
const SymbolIndex *Index) {
const SourceManager &SM = AST.getSourceManager();
llvm::Optional<HoverInfo> HI;
SourceLocation SourceLocationBeg = SM.getMacroArgExpandedLocation(
getBeginningOfIdentifier(Pos, SM, AST.getASTContext().getLangOpts()));
if (auto M = locateMacroAt(SourceLocationBeg, AST.getPreprocessor())) {
HI = getHoverContents(*M, AST);
} else {
auto Decls = getDeclAtPosition(AST, SourceLocationBeg);
if (!Decls.empty())
HI = getHoverContents(Decls.front(), Index);
}
if (!HI && hasDeducedType(AST, SourceLocationBeg)) {
DeducedTypeVisitor V(SourceLocationBeg);
V.TraverseAST(AST.getASTContext());
if (!V.DeducedType.isNull())
HI = getHoverContents(V.DeducedType, V.D, AST.getASTContext(), Index);
}
if (!HI)
return llvm::None;
auto Replacements = format::reformat(
Style, HI->Definition, tooling::Range(0, HI->Definition.size()));
if (auto Formatted =
tooling::applyAllReplacements(HI->Definition, Replacements))
HI->Definition = *Formatted;
HI->SymRange =
getTokenRange(AST.getASTContext().getSourceManager(),
AST.getASTContext().getLangOpts(), SourceLocationBeg);
return HI;
}
std::vector<Location> findReferences(ParsedAST &AST, Position Pos,
uint32_t Limit, const SymbolIndex *Index) {
if (!Limit)
Limit = std::numeric_limits<uint32_t>::max();
std::vector<Location> Results;
const SourceManager &SM = AST.getSourceManager();
auto MainFilePath =
getCanonicalPath(SM.getFileEntryForID(SM.getMainFileID()), SM);
if (!MainFilePath) {
elog("Failed to get a path for the main file, so no references");
return Results;
}
auto Loc = SM.getMacroArgExpandedLocation(
getBeginningOfIdentifier(Pos, SM, AST.getASTContext().getLangOpts()));
// TODO: should we handle macros, too?
auto Decls = getDeclAtPosition(AST, Loc);
// We traverse the AST to find references in the main file.
auto MainFileRefs = findRefs(Decls, AST);
// We may get multiple refs with the same location and different Roles, as
// cross-reference is only interested in locations, we deduplicate them
// by the location to avoid emitting duplicated locations.
MainFileRefs.erase(std::unique(MainFileRefs.begin(), MainFileRefs.end(),
[](const ReferenceFinder::Reference &L,
const ReferenceFinder::Reference &R) {
return L.Loc == R.Loc;
}),
MainFileRefs.end());
for (const auto &Ref : MainFileRefs) {
if (auto Range =
getTokenRange(AST.getASTContext().getSourceManager(),
AST.getASTContext().getLangOpts(), Ref.Loc)) {
Location Result;
Result.range = *Range;
Result.uri = URIForFile::canonicalize(*MainFilePath, *MainFilePath);
Results.push_back(std::move(Result));
}
}
// Now query the index for references from other files.
if (Index && Results.size() < Limit) {
RefsRequest Req;
Req.Limit = Limit;
for (const Decl *D : Decls) {
// Not all symbols can be referenced from outside (e.g. function-locals).
// TODO: we could skip TU-scoped symbols here (e.g. static functions) if
// we know this file isn't a header. The details might be tricky.
if (D->getParentFunctionOrMethod())
continue;
if (auto ID = getSymbolID(D))
Req.IDs.insert(*ID);
}
if (Req.IDs.empty())
return Results;
Index->refs(Req, [&](const Ref &R) {
auto LSPLoc = toLSPLocation(R.Location, *MainFilePath);
// Avoid indexed results for the main file - the AST is authoritative.
if (LSPLoc && LSPLoc->uri.file() != *MainFilePath)
Results.push_back(std::move(*LSPLoc));
});
}
if (Results.size() > Limit)
Results.resize(Limit);
return Results;
}
std::vector<SymbolDetails> getSymbolInfo(ParsedAST &AST, Position Pos) {
const SourceManager &SM = AST.getSourceManager();
auto Loc = SM.getMacroArgExpandedLocation(
getBeginningOfIdentifier(Pos, SM, AST.getASTContext().getLangOpts()));
std::vector<SymbolDetails> Results;
for (const Decl *D : getDeclAtPosition(AST, Loc)) {
SymbolDetails NewSymbol;
if (const NamedDecl *ND = dyn_cast<NamedDecl>(D)) {
std::string QName = printQualifiedName(*ND);
std::tie(NewSymbol.containerName, NewSymbol.name) =
splitQualifiedName(QName);
if (NewSymbol.containerName.empty()) {
if (const auto *ParentND =
dyn_cast_or_null<NamedDecl>(ND->getDeclContext()))
NewSymbol.containerName = printQualifiedName(*ParentND);
}
}
llvm::SmallString<32> USR;
if (!index::generateUSRForDecl(D, USR)) {
NewSymbol.USR = USR.str();
NewSymbol.ID = SymbolID(NewSymbol.USR);
}
Results.push_back(std::move(NewSymbol));
}
if (auto M = locateMacroAt(Loc, AST.getPreprocessor())) {
SymbolDetails NewMacro;
NewMacro.name = M->Name;
llvm::SmallString<32> USR;
if (!index::generateUSRForMacro(NewMacro.name, M->Info->getDefinitionLoc(),
SM, USR)) {
NewMacro.USR = USR.str();
NewMacro.ID = SymbolID(NewMacro.USR);
}
Results.push_back(std::move(NewMacro));
}
return Results;
}
llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, const LocatedSymbol &S) {
OS << S.Name << ": " << S.PreferredDeclaration;
if (S.Definition)
OS << " def=" << *S.Definition;
return OS;
}
// FIXME(nridge): Reduce duplication between this function and declToSym().
static llvm::Optional<TypeHierarchyItem>
declToTypeHierarchyItem(ASTContext &Ctx, const NamedDecl &ND) {
auto &SM = Ctx.getSourceManager();
SourceLocation NameLoc =
spellingLocIfSpelled(findName(&ND), Ctx.getSourceManager());
// getFileLoc is a good choice for us, but we also need to make sure
// sourceLocToPosition won't switch files, so we call getSpellingLoc on top of
// that to make sure it does not switch files.
// FIXME: sourceLocToPosition should not switch files!
SourceLocation BeginLoc = SM.getSpellingLoc(SM.getFileLoc(ND.getBeginLoc()));
SourceLocation EndLoc = SM.getSpellingLoc(SM.getFileLoc(ND.getEndLoc()));
if (NameLoc.isInvalid() || BeginLoc.isInvalid() || EndLoc.isInvalid())
return llvm::None;
Position NameBegin = sourceLocToPosition(SM, NameLoc);
Position NameEnd = sourceLocToPosition(
SM, Lexer::getLocForEndOfToken(NameLoc, 0, SM, Ctx.getLangOpts()));
index::SymbolInfo SymInfo = index::getSymbolInfo(&ND);
// FIXME: this is not classifying constructors, destructors and operators
// correctly (they're all "methods").
SymbolKind SK = indexSymbolKindToSymbolKind(SymInfo.Kind);
TypeHierarchyItem THI;
THI.name = printName(Ctx, ND);
THI.kind = SK;
THI.deprecated = ND.isDeprecated();
THI.range =
Range{sourceLocToPosition(SM, BeginLoc), sourceLocToPosition(SM, EndLoc)};
THI.selectionRange = Range{NameBegin, NameEnd};
if (!THI.range.contains(THI.selectionRange)) {
// 'selectionRange' must be contained in 'range', so in cases where clang
// reports unrelated ranges we need to reconcile somehow.
THI.range = THI.selectionRange;
}
auto FilePath =
getCanonicalPath(SM.getFileEntryForID(SM.getFileID(BeginLoc)), SM);
auto TUPath = getCanonicalPath(SM.getFileEntryForID(SM.getMainFileID()), SM);
if (!FilePath || !TUPath)
return llvm::None; // Not useful without a uri.
THI.uri = URIForFile::canonicalize(*FilePath, *TUPath);
return THI;
}
static Optional<TypeHierarchyItem>
symbolToTypeHierarchyItem(const Symbol &S, const SymbolIndex *Index,
PathRef TUPath) {
auto Loc = symbolToLocation(S, TUPath);
if (!Loc) {
log("Type hierarchy: {0}", Loc.takeError());
return llvm::None;
}
TypeHierarchyItem THI;
THI.name = S.Name;
THI.kind = indexSymbolKindToSymbolKind(S.SymInfo.Kind);
THI.deprecated = (S.Flags & Symbol::Deprecated);
THI.selectionRange = Loc->range;
// FIXME: Populate 'range' correctly
// (https://github.com/clangd/clangd/issues/59).
THI.range = THI.selectionRange;
THI.uri = Loc->uri;
// Store the SymbolID in the 'data' field. The client will
// send this back in typeHierarchy/resolve, allowing us to
// continue resolving additional levels of the type hierarchy.
THI.data = S.ID.str();
return std::move(THI);
}
static void fillSubTypes(const SymbolID &ID,
std::vector<TypeHierarchyItem> &SubTypes,
const SymbolIndex *Index, int Levels, PathRef TUPath) {
RelationsRequest Req;
Req.Subjects.insert(ID);
Req.Predicate = RelationKind::BaseOf;
Index->relations(Req, [&](const SymbolID &Subject, const Symbol &Object) {
if (Optional<TypeHierarchyItem> ChildSym =
symbolToTypeHierarchyItem(Object, Index, TUPath)) {
if (Levels > 1) {
ChildSym->children.emplace();
fillSubTypes(Object.ID, *ChildSym->children, Index, Levels - 1, TUPath);
}
SubTypes.emplace_back(std::move(*ChildSym));
}
});
}
using RecursionProtectionSet = llvm::SmallSet<const CXXRecordDecl *, 4>;
static void fillSuperTypes(const CXXRecordDecl &CXXRD, ASTContext &ASTCtx,
std::vector<TypeHierarchyItem> &SuperTypes,
RecursionProtectionSet &RPSet) {
// typeParents() will replace dependent template specializations
// with their class template, so to avoid infinite recursion for
// certain types of hierarchies, keep the templates encountered
// along the parent chain in a set, and stop the recursion if one
// starts to repeat.
auto *Pattern = CXXRD.getDescribedTemplate() ? &CXXRD : nullptr;
if (Pattern) {
if (!RPSet.insert(Pattern).second) {
return;
}
}
for (const CXXRecordDecl *ParentDecl : typeParents(&CXXRD)) {
if (Optional<TypeHierarchyItem> ParentSym =
declToTypeHierarchyItem(ASTCtx, *ParentDecl)) {
ParentSym->parents.emplace();
fillSuperTypes(*ParentDecl, ASTCtx, *ParentSym->parents, RPSet);
SuperTypes.emplace_back(std::move(*ParentSym));
}
}
if (Pattern) {
RPSet.erase(Pattern);
}
}
const CXXRecordDecl *findRecordTypeAt(ParsedAST &AST, Position Pos) {
const SourceManager &SM = AST.getSourceManager();
SourceLocation SourceLocationBeg = SM.getMacroArgExpandedLocation(
getBeginningOfIdentifier(Pos, SM, AST.getASTContext().getLangOpts()));
auto Decls = getDeclAtPosition(AST, SourceLocationBeg);
if (Decls.empty())
return nullptr;
const Decl *D = Decls[0];
if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
// If this is a variable, use the type of the variable.
return VD->getType().getTypePtr()->getAsCXXRecordDecl();
}
if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
// If this is a method, use the type of the class.
return Method->getParent();
}
// We don't handle FieldDecl because it's not clear what behaviour
// the user would expect: the enclosing class type (as with a
// method), or the field's type (as with a variable).
return dyn_cast<CXXRecordDecl>(D);
}
std::vector<const CXXRecordDecl *> typeParents(const CXXRecordDecl *CXXRD) {
std::vector<const CXXRecordDecl *> Result;
for (auto Base : CXXRD->bases()) {
const CXXRecordDecl *ParentDecl = nullptr;
const Type *Type = Base.getType().getTypePtr();
if (const RecordType *RT = Type->getAs<RecordType>()) {
ParentDecl = RT->getAsCXXRecordDecl();
}
if (!ParentDecl) {
// Handle a dependent base such as "Base<T>" by using the primary
// template.
if (const TemplateSpecializationType *TS =
Type->getAs<TemplateSpecializationType>()) {
TemplateName TN = TS->getTemplateName();
if (TemplateDecl *TD = TN.getAsTemplateDecl()) {
ParentDecl = dyn_cast<CXXRecordDecl>(TD->getTemplatedDecl());
}
}
}
if (ParentDecl)
Result.push_back(ParentDecl);
}
return Result;
}
llvm::Optional<TypeHierarchyItem>
getTypeHierarchy(ParsedAST &AST, Position Pos, int ResolveLevels,
TypeHierarchyDirection Direction, const SymbolIndex *Index,
PathRef TUPath) {
const CXXRecordDecl *CXXRD = findRecordTypeAt(AST, Pos);
if (!CXXRD)
return llvm::None;
Optional<TypeHierarchyItem> Result =
declToTypeHierarchyItem(AST.getASTContext(), *CXXRD);
if (!Result)
return Result;
if (Direction == TypeHierarchyDirection::Parents ||
Direction == TypeHierarchyDirection::Both) {
Result->parents.emplace();
RecursionProtectionSet RPSet;
fillSuperTypes(*CXXRD, AST.getASTContext(), *Result->parents, RPSet);
}
if ((Direction == TypeHierarchyDirection::Children ||
Direction == TypeHierarchyDirection::Both) &&
ResolveLevels > 0) {
Result->children.emplace();
if (Index) {
if (Optional<SymbolID> ID = getSymbolID(CXXRD))
fillSubTypes(*ID, *Result->children, Index, ResolveLevels, TUPath);
}
}
return Result;
}
void resolveTypeHierarchy(TypeHierarchyItem &Item, int ResolveLevels,
TypeHierarchyDirection Direction,
const SymbolIndex *Index) {
// We only support typeHierarchy/resolve for children, because for parents
// we ignore ResolveLevels and return all levels of parents eagerly.
if (Direction == TypeHierarchyDirection::Parents || ResolveLevels == 0)
return;
Item.children.emplace();
if (Index && Item.data) {
// We store the item's SymbolID in the 'data' field, and the client
// passes it back to us in typeHierarchy/resolve.
if (Expected<SymbolID> ID = SymbolID::fromStr(*Item.data)) {
fillSubTypes(*ID, *Item.children, Index, ResolveLevels, Item.uri.file());
}
}
}
FormattedString HoverInfo::present() const {
FormattedString Output;
if (NamespaceScope) {
Output.appendText("Declared in");
// Drop trailing "::".
if (!LocalScope.empty())
Output.appendInlineCode(llvm::StringRef(LocalScope).drop_back(2));
else if (NamespaceScope->empty())
Output.appendInlineCode("global namespace");
else
Output.appendInlineCode(llvm::StringRef(*NamespaceScope).drop_back(2));
}
if (!Definition.empty()) {
Output.appendCodeBlock(Definition);
} else {
// Builtin types
Output.appendCodeBlock(Name);
}
if (!Documentation.empty())
Output.appendText(Documentation);
return Output;
}
llvm::raw_ostream &operator<<(llvm::raw_ostream &OS,
const HoverInfo::Param &P) {
std::vector<llvm::StringRef> Output;
if (P.Type)
Output.push_back(*P.Type);
if (P.Name)
Output.push_back(*P.Name);
OS << llvm::join(Output, " ");
if (P.Default)
OS << " = " << *P.Default;
return OS;
}
llvm::DenseSet<const Decl *> getNonLocalDeclRefs(ParsedAST &AST,
const FunctionDecl *FD) {
if (!FD->hasBody())
return {};
llvm::DenseSet<const Decl *> DeclRefs;
findExplicitReferences(FD, [&](ReferenceLoc Ref) {
for (const Decl *D : Ref.Targets) {
if (!index::isFunctionLocalSymbol(D) && !D->isTemplateParameter() &&
!Ref.IsDecl)
DeclRefs.insert(D);
}
});
return DeclRefs;
}
} // namespace clangd
} // namespace clang