https://github.com/dmpolukhin created https://github.com/llvm/llvm-project/pull/110131
Summary: https://github.com/llvm/llvm-project/pull/109167 serializes FunctionToLambdasMap in the order of pointers in DenseMap. It gives different order with different memory layouts. Fix this issue by using LocalDeclID instead of pointers. Test Plan: check-clang >From c28fd2bb947ab3325a304efed52d17181286e7f3 Mon Sep 17 00:00:00 2001 From: Dmitry Polukhin <dmitry.poluk...@gmail.com> Date: Thu, 26 Sep 2024 07:53:55 -0700 Subject: [PATCH] [C++20][Modules] Fix non-determinism in serialized AST Summary: https://github.com/llvm/llvm-project/pull/109167 serialized FunctionToLambdasMap in the order of pointers in DenseMap. It gives different order with different memeory leayout. Fix this issue by using LocalDeclID instead of pointers. Test Plan: check-clang --- clang/include/clang/AST/DeclID.h | 22 +++++++++++++++++++ clang/include/clang/Serialization/ASTWriter.h | 6 ++--- clang/lib/Serialization/ASTWriter.cpp | 3 +-- clang/lib/Serialization/ASTWriterDecl.cpp | 3 ++- 4 files changed, 28 insertions(+), 6 deletions(-) diff --git a/clang/include/clang/AST/DeclID.h b/clang/include/clang/AST/DeclID.h index f4607e42c4be38..49964b43c7d1d8 100644 --- a/clang/include/clang/AST/DeclID.h +++ b/clang/include/clang/AST/DeclID.h @@ -189,6 +189,7 @@ class LocalDeclID : public DeclIDBase { // Every Decl ID is a local decl ID to the module being writing in ASTWriter. friend class ASTWriter; friend class GlobalDeclID; + friend struct llvm::DenseMapInfo<clang::LocalDeclID>; public: LocalDeclID() : Base() {} @@ -267,6 +268,27 @@ template <> struct DenseMapInfo<clang::GlobalDeclID> { } }; +template <> struct DenseMapInfo<clang::LocalDeclID> { + using LocalDeclID = clang::LocalDeclID; + using DeclID = LocalDeclID::DeclID; + + static LocalDeclID getEmptyKey() { + return LocalDeclID(DenseMapInfo<DeclID>::getEmptyKey()); + } + + static LocalDeclID getTombstoneKey() { + return LocalDeclID(DenseMapInfo<DeclID>::getTombstoneKey()); + } + + static unsigned getHashValue(const LocalDeclID &Key) { + return DenseMapInfo<DeclID>::getHashValue(Key.getRawValue()); + } + + static bool isEqual(const LocalDeclID &L, const LocalDeclID &R) { + return L == R; + } +}; + } // namespace llvm #endif diff --git a/clang/include/clang/Serialization/ASTWriter.h b/clang/include/clang/Serialization/ASTWriter.h index 760866fd9de938..e21d41c8673143 100644 --- a/clang/include/clang/Serialization/ASTWriter.h +++ b/clang/include/clang/Serialization/ASTWriter.h @@ -233,13 +233,13 @@ class ASTWriter : public ASTDeserializationListener, /// instead of comparing the result of `getDeclID()` or `GetDeclRef()`. llvm::SmallPtrSet<const Decl *, 32> PredefinedDecls; - /// Mapping from FunctionDecl to the list of lambda IDs inside the function. + /// Mapping from FunctionDecl ID to the list of lambda IDs inside the + /// function. /// /// These lambdas have to be loaded right after the function they belong to. /// In order to have canonical declaration for lambda class from the same /// module as enclosing function during deserialization. - llvm::DenseMap<const Decl *, SmallVector<LocalDeclID, 4>> - FunctionToLambdasMap; + llvm::DenseMap<LocalDeclID, SmallVector<LocalDeclID, 4>> FunctionToLambdasMap; /// Offset of each declaration in the bitstream, indexed by /// the declaration's ID. diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp index 223727366f61bd..7a40c5c65d39d9 100644 --- a/clang/lib/Serialization/ASTWriter.cpp +++ b/clang/lib/Serialization/ASTWriter.cpp @@ -5713,8 +5713,7 @@ void ASTWriter::WriteDeclAndTypes(ASTContext &Context) { // efficent becuase it allows lazy deserialization. RecordData FunctionToLambdasMapRecord; for (const auto &Pair : FunctionToLambdasMap) { - FunctionToLambdasMapRecord.push_back( - GetDeclRef(Pair.first).getRawValue()); + FunctionToLambdasMapRecord.push_back(Pair.first.getRawValue()); FunctionToLambdasMapRecord.push_back(Pair.second.size()); for (const auto &Lambda : Pair.second) FunctionToLambdasMapRecord.push_back(Lambda.getRawValue()); diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp index 50c090b195d619..b9222a1b33fd74 100644 --- a/clang/lib/Serialization/ASTWriterDecl.cpp +++ b/clang/lib/Serialization/ASTWriterDecl.cpp @@ -1524,7 +1524,8 @@ void ASTDeclWriter::VisitCXXRecordDecl(CXXRecordDecl *D) { // For lambdas inside canonical FunctionDecl remember the mapping. if (auto FD = llvm::dyn_cast_or_null<FunctionDecl>(D->getDeclContext()); FD && FD->isCanonicalDecl()) { - Writer.FunctionToLambdasMap[FD].push_back(Writer.GetDeclRef(D)); + Writer.FunctionToLambdasMap[Writer.GetDeclRef(FD)].push_back( + Writer.GetDeclRef(D)); } } else { Record.push_back(CXXRecNotTemplate); _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
