https://github.com/VitaNuo updated https://github.com/llvm/llvm-project/pull/122726
>From b61110999596363bafdc94904356840febfcfaa5 Mon Sep 17 00:00:00 2001 From: Viktoriia Bakalova <bakal...@google.com> Date: Tue, 14 Jan 2025 14:00:48 +0100 Subject: [PATCH] [WIP][Modules] Delay deserialization of preferred_name attribute at record level. --- clang/include/clang/Serialization/ASTReader.h | 18 ++++ .../clang/Serialization/ASTRecordReader.h | 10 ++ clang/lib/Serialization/ASTReader.cpp | 5 + clang/lib/Serialization/ASTReaderDecl.cpp | 91 ++++++++++++++++++- clang/lib/Serialization/ASTWriter.cpp | 19 +++- clang/test/Modules/preferred_name.cppm | 12 ++- 6 files changed, 142 insertions(+), 13 deletions(-) diff --git a/clang/include/clang/Serialization/ASTReader.h b/clang/include/clang/Serialization/ASTReader.h index 9f978762a6fb6b..4fd51eabe701ba 100644 --- a/clang/include/clang/Serialization/ASTReader.h +++ b/clang/include/clang/Serialization/ASTReader.h @@ -1205,6 +1205,23 @@ class ASTReader /// been completed. std::deque<PendingDeclContextInfo> PendingDeclContextInfos; + /// Deserialization of some attributes must be deferred since they refer + /// to themselves in their type (e.g., preferred_name attribute refers to the + /// typedef that refers back to the template specialization of the template + /// that the attribute is attached to). + /// More attributes that store TypeSourceInfo might be potentially affected, + /// see https://github.com/llvm/llvm-project/issues/56490 for details. + struct DeferredAttribute { + uint64_t RecordIdx; + // Decl to attach a deferred attribute to. + Decl *ParentDecl; + }; + + /// The collection of Decls that have been loaded but some of their attributes + /// have been deferred, paired with the index inside the record pointing + /// at the skipped attribute. + SmallVector<DeferredAttribute> PendingDeferredAttributes; + template <typename DeclTy> using DuplicateObjCDecls = std::pair<DeclTy *, DeclTy *>; @@ -1551,6 +1568,7 @@ class ASTReader void loadPendingDeclChain(Decl *D, uint64_t LocalOffset); void loadObjCCategories(GlobalDeclID ID, ObjCInterfaceDecl *D, unsigned PreviousGeneration = 0); + void loadDeferredAttribute(const DeferredAttribute &DA); RecordLocation getLocalBitOffset(uint64_t GlobalOffset); uint64_t getGlobalBitOffset(ModuleFile &M, uint64_t LocalOffset); diff --git a/clang/include/clang/Serialization/ASTRecordReader.h b/clang/include/clang/Serialization/ASTRecordReader.h index 2561418b78ca7f..b1572ecef9028c 100644 --- a/clang/include/clang/Serialization/ASTRecordReader.h +++ b/clang/include/clang/Serialization/ASTRecordReader.h @@ -337,6 +337,12 @@ class ASTRecordReader /// Reads attributes from the current stream position, advancing Idx. void readAttributes(AttrVec &Attrs); + /// Reads one attribute from the current stream position, advancing Idx. + Attr *readOrDeferAttr(Decl *D); + + /// Reads attributes from the current stream position, advancing Idx. + void readOrDeferAttributes(AttrVec &Attrs, Decl *D); + /// Read an BTFTypeTagAttr object. BTFTypeTagAttr *readBTFTypeTagAttr() { return cast<BTFTypeTagAttr>(readAttr()); @@ -355,6 +361,10 @@ class ASTRecordReader SwitchCase *getSwitchCaseWithID(unsigned ID) { return Reader->getSwitchCaseWithID(ID); } + +private: + Attr *readOrDeferAttrImpl(Decl *D); + void readOrDeferAttributesImpl(AttrVec &Attrs, Decl *D); }; /// Helper class that saves the current stream position and diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp index b53f99732cacce..57d1d4d696290d 100644 --- a/clang/lib/Serialization/ASTReader.cpp +++ b/clang/lib/Serialization/ASTReader.cpp @@ -10079,6 +10079,11 @@ void ASTReader::finishPendingActions() { } PendingDeducedVarTypes.clear(); + // Load the delayed preferred name attributes. + for (unsigned I = 0; I != PendingDeferredAttributes.size(); ++I) + loadDeferredAttribute(PendingDeferredAttributes[I]); + PendingDeferredAttributes.clear(); + // For each decl chain that we wanted to complete while deserializing, mark // it as "still needs to be completed". for (unsigned I = 0; I != PendingIncompleteDeclChains.size(); ++I) { diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp index dee5169ae5723a..043bed8dc7f382 100644 --- a/clang/lib/Serialization/ASTReaderDecl.cpp +++ b/clang/lib/Serialization/ASTReaderDecl.cpp @@ -612,7 +612,7 @@ void ASTDeclReader::VisitDecl(Decl *D) { if (HasAttrs) { AttrVec Attrs; - Record.readAttributes(Attrs); + Record.readOrDeferAttributes(Attrs, D); // Avoid calling setAttrs() directly because it uses Decl::getASTContext() // internally which is unsafe during derialization. D->setAttrsImpl(Attrs, Reader.getContext()); @@ -3118,13 +3118,18 @@ class AttrReader { return Reader.readVersionTuple(); } + void skipInts(unsigned N) { Reader.skipInts(N); } + + unsigned getCurrentIdx() { return Reader.getIdx(); } + OMPTraitInfo *readOMPTraitInfo() { return Reader.readOMPTraitInfo(); } template <typename T> T *readDeclAs() { return Reader.readDeclAs<T>(); } }; } -Attr *ASTRecordReader::readAttr() { +/// Reads one attribute from the current stream position, advancing Idx. +Attr *ASTRecordReader::readOrDeferAttrImpl(Decl *D) { AttrReader Record(*this); auto V = Record.readInt(); if (!V) @@ -3134,6 +3139,20 @@ Attr *ASTRecordReader::readAttr() { // Kind is stored as a 1-based integer because 0 is used to indicate a null // Attr pointer. auto Kind = static_cast<attr::Kind>(V - 1); + // Some attributes refer to themselves during deserialization, thus + // their deserialization must be deferred until their underlying type + // is resolved. + if (Kind == attr::PreferredName) { + if (D != nullptr) { + Reader->PendingDeferredAttributes.push_back( + {Record.getCurrentIdx() - 1, D}); + auto SkipCount = Record.readInt(); + Record.skipInts(SkipCount); + return nullptr; + } + // Ignore the skip count when resolving pending actions. + Record.readInt(); + } ASTContext &Context = getContext(); IdentifierInfo *AttrName = Record.readIdentifier(); @@ -3159,13 +3178,31 @@ Attr *ASTRecordReader::readAttr() { return New; } -/// Reads attributes from the current stream position. -void ASTRecordReader::readAttributes(AttrVec &Attrs) { +void ASTRecordReader::readOrDeferAttributesImpl(AttrVec &Attrs, Decl *D) { for (unsigned I = 0, E = readInt(); I != E; ++I) - if (auto *A = readAttr()) + if (auto *A = readOrDeferAttr(D)) Attrs.push_back(A); } +Attr *ASTRecordReader::readAttr() { return readOrDeferAttrImpl(nullptr); } + +/// Reads attributes from the current stream position. +void ASTRecordReader::readAttributes(AttrVec &Attrs) { + readOrDeferAttributesImpl(Attrs, nullptr); +} + +/// Reads one attribute from the current stream position, advancing Idx. +/// For some attributes (where type depends on itself recursively), defer +/// reading the attribute until the type has been read. +Attr *ASTRecordReader::readOrDeferAttr(Decl *D) { return readOrDeferAttrImpl(D); } + +/// Reads attributes from the current stream position, advancing Idx. +/// For some attributes (where type depends on itself recursively), defer +/// reading the attribute until the type has been read. +void ASTRecordReader::readOrDeferAttributes(AttrVec &Attrs, Decl *D) { + readOrDeferAttributesImpl(Attrs, D); +} + //===----------------------------------------------------------------------===// // ASTReader Implementation //===----------------------------------------------------------------------===// @@ -4424,6 +4461,50 @@ void ASTReader::loadPendingDeclChain(Decl *FirstLocal, uint64_t LocalOffset) { ASTDeclReader::attachLatestDecl(CanonDecl, MostRecent); } +void ASTReader::loadDeferredAttribute( + const DeferredAttribute &DA) { + Decl *D = DA.ParentDecl; + ModuleFile *M = getOwningModuleFile(D); + + unsigned LocalDeclIndex = D->getGlobalID().getLocalDeclIndex(); + const DeclOffset &DOffs = M->DeclOffsets[LocalDeclIndex]; + RecordLocation Loc(M, DOffs.getBitOffset(M->DeclsBlockStartOffset)); + + llvm::BitstreamCursor &Cursor = Loc.F->DeclsCursor; + SavedStreamPosition SavedPosition(Cursor); + if (llvm::Error Err = Cursor.JumpToBit(Loc.Offset)) { + Error(std::move(Err)); + } + + Expected<unsigned> MaybeCode = Cursor.ReadCode(); + if (!MaybeCode) { + llvm::report_fatal_error( + Twine("ASTReader::loadPreferredNameAttribute failed reading code: ") + + toString(MaybeCode.takeError())); + } + unsigned Code = MaybeCode.get(); + + ASTRecordReader Record(*this, *Loc.F); + Expected<unsigned> MaybeRecCode = Record.readRecord(Cursor, Code); + if (!MaybeRecCode) { + llvm::report_fatal_error( + Twine( + "ASTReader::loadPreferredNameAttribute failed reading rec code: ") + + toString(MaybeCode.takeError())); + } + unsigned RecCode = MaybeRecCode.get(); + if (RecCode < DECL_TYPEDEF || RecCode > DECL_LAST) { + llvm::report_fatal_error( + Twine("ASTReader::loadPreferredNameAttribute failed reading rec code: " + "expected valid DeclCode") + + toString(MaybeCode.takeError())); + } + + Record.skipInts(DA.RecordIdx); + Attr *A = Record.readOrDeferAttr(nullptr); + getContext().getDeclAttrs(D).push_back(A); +} + namespace { /// Given an ObjC interface, goes through the modules and links to the diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp index 39004fd4d4c376..d24ca08e1cc988 100644 --- a/clang/lib/Serialization/ASTWriter.cpp +++ b/clang/lib/Serialization/ASTWriter.cpp @@ -37,6 +37,7 @@ #include "clang/AST/Type.h" #include "clang/AST/TypeLoc.h" #include "clang/AST/TypeLocVisitor.h" +#include "clang/Basic/AttrKinds.h" #include "clang/Basic/Diagnostic.h" #include "clang/Basic/DiagnosticOptions.h" #include "clang/Basic/FileEntry.h" @@ -4906,15 +4907,17 @@ void ASTWriter::WriteModuleFileExtension(Sema &SemaRef, void ASTRecordWriter::AddAttr(const Attr *A) { auto &Record = *this; - // FIXME: Clang can't handle the serialization/deserialization of - // preferred_name properly now. See - // https://github.com/llvm/llvm-project/issues/56490 for example. - if (!A || (isa<PreferredNameAttr>(A) && - Writer->isWritingStdCXXNamedModules())) + if (!A) return Record.push_back(0); Record.push_back(A->getKind() + 1); // FIXME: stable encoding, target attrs + auto SkipIdx = Record.size(); + if (A->getKind() == attr::PreferredName) { + // Add placeholder for the size of preferred_name attribute. + Record.push_back(0); + } + Record.AddIdentifierRef(A->getAttrName()); Record.AddIdentifierRef(A->getScopeName()); Record.AddSourceRange(A->getRange()); @@ -4925,6 +4928,12 @@ void ASTRecordWriter::AddAttr(const Attr *A) { Record.push_back(A->isRegularKeywordAttribute()); #include "clang/Serialization/AttrPCHWrite.inc" + + if (A->getKind() == attr::PreferredName) { + // Record the actual size of preferred_name attribute (-1 to count the + // placeholder). + Record[SkipIdx] = Record.size() - SkipIdx - 1; + } } /// Emit the list of attributes to the specified record. diff --git a/clang/test/Modules/preferred_name.cppm b/clang/test/Modules/preferred_name.cppm index 806781a81c5ca7..86ba6ae96db998 100644 --- a/clang/test/Modules/preferred_name.cppm +++ b/clang/test/Modules/preferred_name.cppm @@ -53,10 +53,16 @@ import A; export using ::foo_templ; //--- Use1.cpp -import A; // expected-warning@foo.h:8 {{attribute declaration must precede definition}} -#include "foo.h" // expected-note@foo.h:9 {{previous definition is here}} - +// expected-no-diagnostics +import A; +#include "foo.h" //--- Use2.cpp // expected-no-diagnostics #include "foo.h" import A; + +//--- Use3.cpp +#include "foo.h" +import A; +foo test; +int size = test.size(); // expected-error {{no member named 'size' in 'foo'}} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
