//===- DelayedDiagnostic.h - Delayed declarator diagnostics -----*- 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
 
//
 
//===----------------------------------------------------------------------===//
 
//
 
/// \file
 
/// Defines the classes clang::DelayedDiagnostic and
 
/// clang::AccessedEntity.
 
///
 
/// DelayedDiangostic is used to record diagnostics that are being
 
/// conditionally produced during declarator parsing.  Certain kinds of
 
/// diagnostics -- notably deprecation and access control -- are suppressed
 
/// based on semantic properties of the parsed declaration that aren't known
 
/// until it is fully parsed.
 
//
 
//===----------------------------------------------------------------------===//
 
 
 
#ifndef LLVM_CLANG_SEMA_DELAYEDDIAGNOSTIC_H
 
#define LLVM_CLANG_SEMA_DELAYEDDIAGNOSTIC_H
 
 
 
#include "clang/AST/DeclAccessPair.h"
 
#include "clang/AST/DeclBase.h"
 
#include "clang/AST/DeclCXX.h"
 
#include "clang/AST/Type.h"
 
#include "clang/Basic/LLVM.h"
 
#include "clang/Basic/PartialDiagnostic.h"
 
#include "clang/Basic/SourceLocation.h"
 
#include "clang/Basic/Specifiers.h"
 
#include "clang/Sema/Sema.h"
 
#include "llvm/ADT/ArrayRef.h"
 
#include "llvm/ADT/SmallVector.h"
 
#include "llvm/ADT/StringRef.h"
 
#include "llvm/Support/Casting.h"
 
#include <cassert>
 
#include <cstddef>
 
#include <utility>
 
 
 
namespace clang {
 
 
 
class ObjCInterfaceDecl;
 
class ObjCPropertyDecl;
 
 
 
namespace sema {
 
 
 
/// A declaration being accessed, together with information about how
 
/// it was accessed.
 
class AccessedEntity {
 
public:
 
  /// A member declaration found through lookup.  The target is the
 
  /// member.
 
  enum MemberNonce { Member };
 
 
 
  /// A hierarchy (base-to-derived or derived-to-base) conversion.
 
  /// The target is the base class.
 
  enum BaseNonce { Base };
 
 
 
  AccessedEntity(PartialDiagnostic::DiagStorageAllocator &Allocator,
 
                 MemberNonce _, CXXRecordDecl *NamingClass,
 
                 DeclAccessPair FoundDecl, QualType BaseObjectType)
 
      : Access(FoundDecl.getAccess()), IsMember(true),
 
        Target(FoundDecl.getDecl()), NamingClass(NamingClass),
 
        BaseObjectType(BaseObjectType), Diag(0, Allocator) {}
 
 
 
  AccessedEntity(PartialDiagnostic::DiagStorageAllocator &Allocator,
 
                 BaseNonce _, CXXRecordDecl *BaseClass,
 
                 CXXRecordDecl *DerivedClass, AccessSpecifier Access)
 
      : Access(Access), IsMember(false), Target(BaseClass),
 
        NamingClass(DerivedClass), Diag(0, Allocator) {}
 
 
 
  bool isMemberAccess() const { return IsMember; }
 
 
 
  bool isQuiet() const { return Diag.getDiagID() == 0; }
 
 
 
  AccessSpecifier getAccess() const { return AccessSpecifier(Access); }
 
 
 
  // These apply to member decls...
 
  NamedDecl *getTargetDecl() const { return Target; }
 
  CXXRecordDecl *getNamingClass() const { return NamingClass; }
 
 
 
  // ...and these apply to hierarchy conversions.
 
  CXXRecordDecl *getBaseClass() const {
 
    assert(!IsMember); return cast<CXXRecordDecl>(Target);
 
  }
 
  CXXRecordDecl *getDerivedClass() const { return NamingClass; }
 
 
 
  /// Retrieves the base object type, important when accessing
 
  /// an instance member.
 
  QualType getBaseObjectType() const { return BaseObjectType; }
 
 
 
  /// Sets a diagnostic to be performed.  The diagnostic is given
 
  /// four (additional) arguments:
 
  ///   %0 - 0 if the entity was private, 1 if protected
 
  ///   %1 - the DeclarationName of the entity
 
  ///   %2 - the TypeDecl type of the naming class
 
  ///   %3 - the TypeDecl type of the declaring class
 
  void setDiag(const PartialDiagnostic &PDiag) {
 
    assert(isQuiet() && "partial diagnostic already defined");
 
    Diag = PDiag;
 
  }
 
  PartialDiagnostic &setDiag(unsigned DiagID) {
 
    assert(isQuiet() && "partial diagnostic already defined");
 
    assert(DiagID && "creating null diagnostic");
 
    Diag.Reset(DiagID);
 
    return Diag;
 
  }
 
  const PartialDiagnostic &getDiag() const {
 
    return Diag;
 
  }
 
 
 
private:
 
  unsigned Access : 2;
 
  unsigned IsMember : 1;
 
  NamedDecl *Target;
 
  CXXRecordDecl *NamingClass;
 
  QualType BaseObjectType;
 
  PartialDiagnostic Diag;
 
};
 
 
 
/// A diagnostic message which has been conditionally emitted pending
 
/// the complete parsing of the current declaration.
 
class DelayedDiagnostic {
 
public:
 
  enum DDKind : unsigned char { Availability, Access, ForbiddenType };
 
 
 
  DDKind Kind;
 
  bool Triggered;
 
 
 
  SourceLocation Loc;
 
 
 
  void Destroy();
 
 
 
  static DelayedDiagnostic makeAvailability(AvailabilityResult AR,
 
                                            ArrayRef<SourceLocation> Locs,
 
                                            const NamedDecl *ReferringDecl,
 
                                            const NamedDecl *OffendingDecl,
 
                                            const ObjCInterfaceDecl *UnknownObjCClass,
 
                                            const ObjCPropertyDecl  *ObjCProperty,
 
                                            StringRef Msg,
 
                                            bool ObjCPropertyAccess);
 
 
 
  static DelayedDiagnostic makeAccess(SourceLocation Loc,
 
                                      const AccessedEntity &Entity) {
 
    DelayedDiagnostic DD;
 
    DD.Kind = Access;
 
    DD.Triggered = false;
 
    DD.Loc = Loc;
 
    new (&DD.getAccessData()) AccessedEntity(Entity);
 
    return DD;
 
  }
 
 
 
  static DelayedDiagnostic makeForbiddenType(SourceLocation loc,
 
                                             unsigned diagnostic,
 
                                             QualType type,
 
                                             unsigned argument) {
 
    DelayedDiagnostic DD;
 
    DD.Kind = ForbiddenType;
 
    DD.Triggered = false;
 
    DD.Loc = loc;
 
    DD.ForbiddenTypeData.Diagnostic = diagnostic;
 
    DD.ForbiddenTypeData.OperandType = type.getAsOpaquePtr();
 
    DD.ForbiddenTypeData.Argument = argument;
 
    return DD;
 
  }
 
 
 
  AccessedEntity &getAccessData() {
 
    assert(Kind == Access && "Not an access diagnostic.");
 
    return *reinterpret_cast<AccessedEntity*>(AccessData);
 
  }
 
  const AccessedEntity &getAccessData() const {
 
    assert(Kind == Access && "Not an access diagnostic.");
 
    return *reinterpret_cast<const AccessedEntity*>(AccessData);
 
  }
 
 
 
  const NamedDecl *getAvailabilityReferringDecl() const {
 
    assert(Kind == Availability && "Not an availability diagnostic.");
 
    return AvailabilityData.ReferringDecl;
 
  }
 
 
 
  const NamedDecl *getAvailabilityOffendingDecl() const {
 
    return AvailabilityData.OffendingDecl;
 
  }
 
 
 
  StringRef getAvailabilityMessage() const {
 
    assert(Kind == Availability && "Not an availability diagnostic.");
 
    return StringRef(AvailabilityData.Message, AvailabilityData.MessageLen);
 
  }
 
 
 
  ArrayRef<SourceLocation> getAvailabilitySelectorLocs() const {
 
    assert(Kind == Availability && "Not an availability diagnostic.");
 
    return llvm::ArrayRef(AvailabilityData.SelectorLocs,
 
                          AvailabilityData.NumSelectorLocs);
 
  }
 
 
 
  AvailabilityResult getAvailabilityResult() const {
 
    assert(Kind == Availability && "Not an availability diagnostic.");
 
    return AvailabilityData.AR;
 
  }
 
 
 
  /// The diagnostic ID to emit.  Used like so:
 
  ///   Diag(diag.Loc, diag.getForbiddenTypeDiagnostic())
 
  ///     << diag.getForbiddenTypeOperand()
 
  ///     << diag.getForbiddenTypeArgument();
 
  unsigned getForbiddenTypeDiagnostic() const {
 
    assert(Kind == ForbiddenType && "not a forbidden-type diagnostic");
 
    return ForbiddenTypeData.Diagnostic;
 
  }
 
 
 
  unsigned getForbiddenTypeArgument() const {
 
    assert(Kind == ForbiddenType && "not a forbidden-type diagnostic");
 
    return ForbiddenTypeData.Argument;
 
  }
 
 
 
  QualType getForbiddenTypeOperand() const {
 
    assert(Kind == ForbiddenType && "not a forbidden-type diagnostic");
 
    return QualType::getFromOpaquePtr(ForbiddenTypeData.OperandType);
 
  }
 
 
 
  const ObjCInterfaceDecl *getUnknownObjCClass() const {
 
    return AvailabilityData.UnknownObjCClass;
 
  }
 
 
 
  const ObjCPropertyDecl *getObjCProperty() const {
 
    return AvailabilityData.ObjCProperty;
 
  }
 
 
 
  bool getObjCPropertyAccess() const {
 
    return AvailabilityData.ObjCPropertyAccess;
 
  }
 
 
 
private:
 
  struct AD {
 
    const NamedDecl *ReferringDecl;
 
    const NamedDecl *OffendingDecl;
 
    const ObjCInterfaceDecl *UnknownObjCClass;
 
    const ObjCPropertyDecl  *ObjCProperty;
 
    const char *Message;
 
    size_t MessageLen;
 
    SourceLocation *SelectorLocs;
 
    size_t NumSelectorLocs;
 
    AvailabilityResult AR;
 
    bool ObjCPropertyAccess;
 
  };
 
 
 
  struct FTD {
 
    unsigned Diagnostic;
 
    unsigned Argument;
 
    void *OperandType;
 
  };
 
 
 
  union {
 
    struct AD AvailabilityData;
 
    struct FTD ForbiddenTypeData;
 
 
 
    /// Access control.
 
    char AccessData[sizeof(AccessedEntity)];
 
  };
 
};
 
 
 
/// A collection of diagnostics which were delayed.
 
class DelayedDiagnosticPool {
 
  const DelayedDiagnosticPool *Parent;
 
  SmallVector<DelayedDiagnostic, 4> Diagnostics;
 
 
 
public:
 
  DelayedDiagnosticPool(const DelayedDiagnosticPool *parent) : Parent(parent) {}
 
 
 
  DelayedDiagnosticPool(const DelayedDiagnosticPool &) = delete;
 
  DelayedDiagnosticPool &operator=(const DelayedDiagnosticPool &) = delete;
 
 
 
  DelayedDiagnosticPool(DelayedDiagnosticPool &&Other)
 
      : Parent(Other.Parent), Diagnostics(std::move(Other.Diagnostics)) {
 
    Other.Diagnostics.clear();
 
  }
 
 
 
  DelayedDiagnosticPool &operator=(DelayedDiagnosticPool &&Other) {
 
    Parent = Other.Parent;
 
    Diagnostics = std::move(Other.Diagnostics);
 
    Other.Diagnostics.clear();
 
    return *this;
 
  }
 
 
 
  ~DelayedDiagnosticPool() {
 
    for (SmallVectorImpl<DelayedDiagnostic>::iterator
 
           i = Diagnostics.begin(), e = Diagnostics.end(); i != e; ++i)
 
      i->Destroy();
 
  }
 
 
 
  const DelayedDiagnosticPool *getParent() const { return Parent; }
 
 
 
  /// Does this pool, or any of its ancestors, contain any diagnostics?
 
  bool empty() const {
 
    return (Diagnostics.empty() && (!Parent || Parent->empty()));
 
  }
 
 
 
  /// Add a diagnostic to this pool.
 
  void add(const DelayedDiagnostic &diag) {
 
    Diagnostics.push_back(diag);
 
  }
 
 
 
  /// Steal the diagnostics from the given pool.
 
  void steal(DelayedDiagnosticPool &pool) {
 
    if (pool.Diagnostics.empty()) return;
 
 
 
    if (Diagnostics.empty()) {
 
      Diagnostics = std::move(pool.Diagnostics);
 
    } else {
 
      Diagnostics.append(pool.pool_begin(), pool.pool_end());
 
    }
 
    pool.Diagnostics.clear();
 
  }
 
 
 
  using pool_iterator = SmallVectorImpl<DelayedDiagnostic>::const_iterator;
 
 
 
  pool_iterator pool_begin() const { return Diagnostics.begin(); }
 
  pool_iterator pool_end() const { return Diagnostics.end(); }
 
  bool pool_empty() const { return Diagnostics.empty(); }
 
};
 
 
 
} // namespace clang
 
 
 
/// Add a diagnostic to the current delay pool.
 
inline void Sema::DelayedDiagnostics::add(const sema::DelayedDiagnostic &diag) {
 
  assert(shouldDelayDiagnostics() && "trying to delay without pool");
 
  CurPool->add(diag);
 
}
 
 
 
} // namespace clang
 
 
 
#endif // LLVM_CLANG_SEMA_DELAYEDDIAGNOSTIC_H