llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: None (halbi2) <details> <summary>Changes</summary> std::equal(std::byte) currently has sub-optimal codegen due to enum types not being recognized as trivially equality comparable. In order to fix this we make them trivially comparable. In the process I factored out into a standalone function EqualityComparisonIsDefaulted and refactored the test cases. Enum types cannot have operator== which is a hidden friend. Fixes #<!-- -->132672 --- Full diff: https://github.com/llvm/llvm-project/pull/169079.diff 2 Files Affected: - (modified) clang/lib/Sema/SemaTypeTraits.cpp (+50-33) - (modified) clang/test/SemaCXX/type-traits.cpp (+20-26) ``````````diff diff --git a/clang/lib/Sema/SemaTypeTraits.cpp b/clang/lib/Sema/SemaTypeTraits.cpp index 38877967af05e..581989e6d0069 100644 --- a/clang/lib/Sema/SemaTypeTraits.cpp +++ b/clang/lib/Sema/SemaTypeTraits.cpp @@ -591,6 +591,43 @@ static bool HasNoThrowOperator(CXXRecordDecl *RD, OverloadedOperatorKind Op, return false; } +static bool EqualityComparisonIsDefaulted(Sema &S, const TypeDecl *Decl, + SourceLocation KeyLoc) { + CanQualType T = S.Context.getCanonicalTagType(Decl); + + EnterExpressionEvaluationContext UnevaluatedContext( + S, Sema::ExpressionEvaluationContext::Unevaluated); + Sema::SFINAETrap SFINAE(S, /*ForValidityCheck=*/true); + Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl()); + + // const ClassT& obj; + OpaqueValueExpr Operand( + KeyLoc, T.withConst(), + ExprValueKind::VK_LValue); + UnresolvedSet<16> Functions; + // obj == obj; + S.LookupBinOp(S.TUScope, {}, BinaryOperatorKind::BO_EQ, Functions); + + auto Result = S.CreateOverloadedBinOp(KeyLoc, BinaryOperatorKind::BO_EQ, + Functions, &Operand, &Operand); + if (Result.isInvalid() || SFINAE.hasErrorOccurred()) + return false; + + const auto *CallExpr = dyn_cast<CXXOperatorCallExpr>(Result.get()); + if (!CallExpr) + return isa<EnumDecl>(Decl); + const auto *Callee = CallExpr->getDirectCallee(); + auto ParamT = Callee->getParamDecl(0)->getType(); + if (!Callee->isDefaulted()) + return false; + if (!ParamT->isReferenceType()) { + const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Decl); + if (!RD->isTriviallyCopyable()) + return false; + } + return S.Context.hasSameUnqualifiedType(ParamT.getNonReferenceType(), T); +} + static bool HasNonDeletedDefaultedEqualityComparison(Sema &S, const CXXRecordDecl *Decl, SourceLocation KeyLoc) { @@ -599,36 +636,8 @@ static bool HasNonDeletedDefaultedEqualityComparison(Sema &S, if (Decl->isLambda()) return Decl->isCapturelessLambda(); - CanQualType T = S.Context.getCanonicalTagType(Decl); - { - EnterExpressionEvaluationContext UnevaluatedContext( - S, Sema::ExpressionEvaluationContext::Unevaluated); - Sema::SFINAETrap SFINAE(S, /*ForValidityCheck=*/true); - Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl()); - - // const ClassT& obj; - OpaqueValueExpr Operand(KeyLoc, T.withConst(), ExprValueKind::VK_LValue); - UnresolvedSet<16> Functions; - // obj == obj; - S.LookupBinOp(S.TUScope, {}, BinaryOperatorKind::BO_EQ, Functions); - - auto Result = S.CreateOverloadedBinOp(KeyLoc, BinaryOperatorKind::BO_EQ, - Functions, &Operand, &Operand); - if (Result.isInvalid() || SFINAE.hasErrorOccurred()) - return false; - - const auto *CallExpr = dyn_cast<CXXOperatorCallExpr>(Result.get()); - if (!CallExpr) - return false; - const auto *Callee = CallExpr->getDirectCallee(); - auto ParamT = Callee->getParamDecl(0)->getType(); - if (!Callee->isDefaulted()) - return false; - if (!ParamT->isReferenceType() && !Decl->isTriviallyCopyable()) - return false; - if (!S.Context.hasSameUnqualifiedType(ParamT.getNonReferenceType(), T)) - return false; - } + if (!EqualityComparisonIsDefaulted(S, Decl, KeyLoc)) + return false; return llvm::all_of(Decl->bases(), [&](const CXXBaseSpecifier &BS) { @@ -643,9 +652,12 @@ static bool HasNonDeletedDefaultedEqualityComparison(Sema &S, Type = Type->getBaseElementTypeUnsafe() ->getCanonicalTypeUnqualified(); - if (Type->isReferenceType() || Type->isEnumeralType()) + if (Type->isReferenceType()) return false; - if (const auto *RD = Type->getAsCXXRecordDecl()) + if (Type->isEnumeralType()) { + EnumDecl *ED = Type->castAs<EnumType>()->getOriginalDecl()->getDefinitionOrSelf(); + return EqualityComparisonIsDefaulted(S, ED, KeyLoc); + } else if (const auto *RD = Type->getAsCXXRecordDecl()) return HasNonDeletedDefaultedEqualityComparison(S, RD, KeyLoc); return true; }); @@ -655,9 +667,14 @@ static bool isTriviallyEqualityComparableType(Sema &S, QualType Type, SourceLocation KeyLoc) { QualType CanonicalType = Type.getCanonicalType(); if (CanonicalType->isIncompleteType() || CanonicalType->isDependentType() || - CanonicalType->isEnumeralType() || CanonicalType->isArrayType()) + CanonicalType->isArrayType()) return false; + if (CanonicalType->isEnumeralType()) { + EnumDecl *ED = CanonicalType->castAs<EnumType>()->getOriginalDecl()->getDefinitionOrSelf(); + return EqualityComparisonIsDefaulted(S, ED, KeyLoc); + } + if (const auto *RD = CanonicalType->getAsCXXRecordDecl()) { if (!HasNonDeletedDefaultedEqualityComparison(S, RD, KeyLoc)) return false; diff --git a/clang/test/SemaCXX/type-traits.cpp b/clang/test/SemaCXX/type-traits.cpp index 9ef44d0346b48..76fa4a9c2b936 100644 --- a/clang/test/SemaCXX/type-traits.cpp +++ b/clang/test/SemaCXX/type-traits.cpp @@ -3993,6 +3993,10 @@ namespace is_trivially_equality_comparable { struct ForwardDeclared; // expected-note {{forward declaration of 'is_trivially_equality_comparable::ForwardDeclared'}} static_assert(!__is_trivially_equality_comparable(ForwardDeclared)); // expected-error {{incomplete type 'ForwardDeclared' used in type trait expression}} +enum Enum {}; +enum EnumWithOpEq {}; +bool operator==(EnumWithOpEq, EnumWithOpEq); + static_assert(!__is_trivially_equality_comparable(void)); static_assert(__is_trivially_equality_comparable(int)); static_assert(!__is_trivially_equality_comparable(int[])); @@ -4000,6 +4004,8 @@ static_assert(!__is_trivially_equality_comparable(int[3])); static_assert(!__is_trivially_equality_comparable(float)); static_assert(!__is_trivially_equality_comparable(double)); static_assert(!__is_trivially_equality_comparable(long double)); +static_assert(__is_trivially_equality_comparable(Enum)); +static_assert(!__is_trivially_equality_comparable(EnumWithOpEq)); struct NonTriviallyEqualityComparableNoComparator { int i; @@ -4033,19 +4039,21 @@ struct TriviallyEqualityComparable { }; static_assert(__is_trivially_equality_comparable(TriviallyEqualityComparable)); -struct TriviallyEqualityComparableContainsArray { - int a[4]; +template <class T> +struct TriviallyEqualityComparableContains { + T t; - bool operator==(const TriviallyEqualityComparableContainsArray&) const = default; + bool operator==(const TriviallyEqualityComparableContains&) const = default; }; -static_assert(__is_trivially_equality_comparable(TriviallyEqualityComparableContainsArray)); -struct TriviallyEqualityComparableContainsMultiDimensionArray { - int a[4][4]; - - bool operator==(const TriviallyEqualityComparableContainsMultiDimensionArray&) const = default; -}; -static_assert(__is_trivially_equality_comparable(TriviallyEqualityComparableContainsMultiDimensionArray)); +static_assert(__is_trivially_equality_comparable(TriviallyEqualityComparableContains<int>)); +static_assert(!__is_trivially_equality_comparable(TriviallyEqualityComparableContains<float>)); +static_assert(!__is_trivially_equality_comparable(TriviallyEqualityComparableContains<double>)); +static_assert(!__is_trivially_equality_comparable(TriviallyEqualityComparableContains<long double>)); +static_assert(__is_trivially_equality_comparable(TriviallyEqualityComparableContains<int[4]>)); +static_assert(__is_trivially_equality_comparable(TriviallyEqualityComparableContains<int[4][4]>)); +static_assert(__is_trivially_equality_comparable(TriviallyEqualityComparableContains<Enum>)); +static_assert(!__is_trivially_equality_comparable(TriviallyEqualityComparableContains<EnumWithOpEq>)); auto GetNonCapturingLambda() { return [](){ return 42; }; } @@ -4196,13 +4204,6 @@ struct NotTriviallyEqualityComparableNonTriviallyComparableBase : NotTriviallyEq }; static_assert(!__is_trivially_equality_comparable(NotTriviallyEqualityComparableNonTriviallyComparableBase)); -enum E { - a, - b -}; -bool operator==(E, E) { return false; } -static_assert(!__is_trivially_equality_comparable(E)); - struct NotTriviallyEqualityComparableHasEnum { E e; bool operator==(const NotTriviallyEqualityComparableHasEnum&) const = default; @@ -4434,15 +4435,8 @@ struct NotTriviallyEqualityComparableHasReferenceMember { }; static_assert(!__is_trivially_equality_comparable(NotTriviallyEqualityComparableHasReferenceMember)); -enum E { - a, - b -}; -bool operator==(E, E) { return false; } -static_assert(!__is_trivially_equality_comparable(E)); - struct NotTriviallyEqualityComparableHasEnum { - E e; + Enum e; friend bool operator==(const NotTriviallyEqualityComparableHasEnum&, const NotTriviallyEqualityComparableHasEnum&) = default; }; static_assert(!__is_trivially_equality_comparable(NotTriviallyEqualityComparableHasEnum)); @@ -4465,7 +4459,7 @@ static_assert(__is_trivially_equality_comparable(TriviallyEqualityComparableRefC } #endif // __cplusplus >= 202002L -}; +} namespace can_pass_in_regs { `````````` </details> https://github.com/llvm/llvm-project/pull/169079 _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
