//===- MacroInfo.h - Information about #defined identifiers -----*- 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 clang::MacroInfo and clang::MacroDirective classes.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_LEX_MACROINFO_H
#define LLVM_CLANG_LEX_MACROINFO_H
#include "clang/Lex/Token.h"
#include "clang/Basic/LLVM.h"
#include "clang/Basic/SourceLocation.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/Allocator.h"
#include <algorithm>
#include <cassert>
namespace clang {
class DefMacroDirective;
class IdentifierInfo;
class Module;
class Preprocessor;
class SourceManager;
/// Encapsulates the data about a macro definition (e.g. its tokens).
///
/// There's an instance of this class for every #define.
class MacroInfo {
//===--------------------------------------------------------------------===//
// State set when the macro is defined.
/// The location the macro is defined.
SourceLocation Location;
/// The location of the last token in the macro.
SourceLocation EndLocation;
/// The list of arguments for a function-like macro.
///
/// ParameterList points to the first of NumParameters pointers.
///
/// This can be empty, for, e.g. "#define X()". In a C99-style variadic
/// macro, this includes the \c __VA_ARGS__ identifier on the list.
IdentifierInfo **ParameterList = nullptr;
/// This is the list of tokens that the macro is defined to.
const Token *ReplacementTokens = nullptr;
/// \see ParameterList
unsigned NumParameters = 0;
/// \see ReplacementTokens
unsigned NumReplacementTokens = 0;
/// Length in characters of the macro definition.
mutable unsigned DefinitionLength;
mutable bool IsDefinitionLengthCached : 1;
/// True if this macro is function-like, false if it is object-like.
bool IsFunctionLike : 1;
/// True if this macro is of the form "#define X(...)" or
/// "#define X(Y,Z,...)".
///
/// The __VA_ARGS__ token should be replaced with the contents of "..." in an
/// invocation.
bool IsC99Varargs : 1;
/// True if this macro is of the form "#define X(a...)".
///
/// The "a" identifier in the replacement list will be replaced with all
/// arguments of the macro starting with the specified one.
bool IsGNUVarargs : 1;
/// True if this macro requires processing before expansion.
///
/// This is the case for builtin macros such as __LINE__, so long as they have
/// not been redefined, but not for regular predefined macros from the
/// "<built-in>" memory buffer (see Preprocessing::getPredefinesFileID).
bool IsBuiltinMacro : 1;
/// Whether this macro contains the sequence ", ## __VA_ARGS__"
bool HasCommaPasting : 1;
//===--------------------------------------------------------------------===//
// State that changes as the macro is used.
/// True if we have started an expansion of this macro already.
///
/// This disables recursive expansion, which would be quite bad for things
/// like \#define A A.
bool IsDisabled : 1;
/// True if this macro is either defined in the main file and has
/// been used, or if it is not defined in the main file.
///
/// This is used to emit -Wunused-macros diagnostics.
bool IsUsed : 1;
/// True if this macro can be redefined without emitting a warning.
bool IsAllowRedefinitionsWithoutWarning : 1;
/// Must warn if the macro is unused at the end of translation unit.
bool IsWarnIfUnused : 1;
/// Whether this macro was used as header guard.
bool UsedForHeaderGuard : 1;
// Only the Preprocessor gets to create these.
MacroInfo(SourceLocation DefLoc);
public:
/// Return the location that the macro was defined at.
SourceLocation getDefinitionLoc() const { return Location; }
/// Set the location of the last token in the macro.
void setDefinitionEndLoc(SourceLocation EndLoc) { EndLocation = EndLoc; }
/// Return the location of the last token in the macro.
SourceLocation getDefinitionEndLoc() const { return EndLocation; }
/// Get length in characters of the macro definition.
unsigned getDefinitionLength(const SourceManager &SM) const {
if (IsDefinitionLengthCached)
return DefinitionLength;
return getDefinitionLengthSlow(SM);
}
/// Return true if the specified macro definition is equal to
/// this macro in spelling, arguments, and whitespace.
///
/// \param Syntactically if true, the macro definitions can be identical even
/// if they use different identifiers for the function macro parameters.
/// Otherwise the comparison is lexical and this implements the rules in
/// C99 6.10.3.
bool isIdenticalTo(const MacroInfo &Other, Preprocessor &PP,
bool Syntactically) const;
/// Set or clear the isBuiltinMacro flag.
void setIsBuiltinMacro(bool Val = true) { IsBuiltinMacro = Val; }
/// Set the value of the IsUsed flag.
void setIsUsed(bool Val) { IsUsed = Val; }
/// Set the value of the IsAllowRedefinitionsWithoutWarning flag.
void setIsAllowRedefinitionsWithoutWarning(bool Val) {
IsAllowRedefinitionsWithoutWarning = Val;
}
/// Set the value of the IsWarnIfUnused flag.
void setIsWarnIfUnused(bool val) { IsWarnIfUnused = val; }
/// Set the specified list of identifiers as the parameter list for
/// this macro.
void setParameterList(ArrayRef<IdentifierInfo *> List,
llvm::BumpPtrAllocator &PPAllocator) {
assert(ParameterList == nullptr && NumParameters == 0 &&
"Parameter list already set!");
if (List.empty())
return;
NumParameters = List.size();
ParameterList = PPAllocator.Allocate<IdentifierInfo *>(List.size());
std::copy(List.begin(), List.end(), ParameterList);
}
/// Parameters - The list of parameters for a function-like macro. This can
/// be empty, for, e.g. "#define X()".
using param_iterator = IdentifierInfo *const *;
bool param_empty() const { return NumParameters == 0; }
param_iterator param_begin() const { return ParameterList; }
param_iterator param_end() const { return ParameterList + NumParameters; }
unsigned getNumParams() const { return NumParameters; }
ArrayRef<const IdentifierInfo *> params() const {
return ArrayRef<const IdentifierInfo *>(ParameterList, NumParameters);
}
/// Return the parameter number of the specified identifier,
/// or -1 if the identifier is not a formal parameter identifier.
int getParameterNum(const IdentifierInfo *Arg) const {
for (param_iterator I = param_begin(), E = param_end(); I != E; ++I)
if (*I == Arg)
return I - param_begin();
return -1;
}
/// Function/Object-likeness. Keep track of whether this macro has formal
/// parameters.
void setIsFunctionLike() { IsFunctionLike = true; }
bool isFunctionLike() const { return IsFunctionLike; }
bool isObjectLike() const { return !IsFunctionLike; }
/// Varargs querying methods. This can only be set for function-like macros.
void setIsC99Varargs() { IsC99Varargs = true; }
void setIsGNUVarargs() { IsGNUVarargs = true; }
bool isC99Varargs() const { return IsC99Varargs; }
bool isGNUVarargs() const { return IsGNUVarargs; }
bool isVariadic() const { return IsC99Varargs | IsGNUVarargs; }
/// Return true if this macro requires processing before expansion.
///
/// This is true only for builtin macro, such as \__LINE__, whose values
/// are not given by fixed textual expansions. Regular predefined macros
/// from the "<built-in>" buffer are not reported as builtins by this
/// function.
bool isBuiltinMacro() const { return IsBuiltinMacro; }
bool hasCommaPasting() const { return HasCommaPasting; }
void setHasCommaPasting() { HasCommaPasting = true; }
/// Return false if this macro is defined in the main file and has
/// not yet been used.
bool isUsed() const { return IsUsed; }
/// Return true if this macro can be redefined without warning.
bool isAllowRedefinitionsWithoutWarning() const {
return IsAllowRedefinitionsWithoutWarning;
}
/// Return true if we should emit a warning if the macro is unused.
bool isWarnIfUnused() const { return IsWarnIfUnused; }
/// Return the number of tokens that this macro expands to.
unsigned getNumTokens() const { return NumReplacementTokens; }
const Token &getReplacementToken(unsigned Tok) const {
assert(Tok < NumReplacementTokens && "Invalid token #");
return ReplacementTokens[Tok];
}
using const_tokens_iterator = const Token *;
const_tokens_iterator tokens_begin() const { return ReplacementTokens; }
const_tokens_iterator tokens_end() const {
return ReplacementTokens + NumReplacementTokens;
}
bool tokens_empty() const { return NumReplacementTokens == 0; }
ArrayRef<Token> tokens() const {
return llvm::ArrayRef(ReplacementTokens, NumReplacementTokens);
}
llvm::MutableArrayRef<Token>
allocateTokens(unsigned NumTokens, llvm::BumpPtrAllocator &PPAllocator) {
assert(ReplacementTokens == nullptr && NumReplacementTokens == 0 &&
"Token list already allocated!");
NumReplacementTokens = NumTokens;
Token *NewReplacementTokens = PPAllocator.Allocate<Token>(NumTokens);
ReplacementTokens = NewReplacementTokens;
return llvm::MutableArrayRef(NewReplacementTokens, NumTokens);
}
void setTokens(ArrayRef<Token> Tokens, llvm::BumpPtrAllocator &PPAllocator) {
assert(
!IsDefinitionLengthCached &&
"Changing replacement tokens after definition length got calculated");
assert(ReplacementTokens == nullptr && NumReplacementTokens == 0 &&
"Token list already set!");
if (Tokens.empty())
return;
NumReplacementTokens = Tokens.size();
Token *NewReplacementTokens = PPAllocator.Allocate<Token>(Tokens.size());
std::copy(Tokens.begin(), Tokens.end(), NewReplacementTokens);
ReplacementTokens = NewReplacementTokens;
}
/// Return true if this macro is enabled.
///
/// In other words, that we are not currently in an expansion of this macro.
bool isEnabled() const { return !IsDisabled; }
void EnableMacro() {
assert(IsDisabled && "Cannot enable an already-enabled macro!");
IsDisabled = false;
}
void DisableMacro() {
assert(!IsDisabled && "Cannot disable an already-disabled macro!");
IsDisabled = true;
}
/// Determine whether this macro was used for a header guard.
bool isUsedForHeaderGuard() const { return UsedForHeaderGuard; }
void setUsedForHeaderGuard(bool Val) { UsedForHeaderGuard = Val; }
void dump() const;
private:
friend class Preprocessor;
unsigned getDefinitionLengthSlow(const SourceManager &SM) const;
};
/// Encapsulates changes to the "macros namespace" (the location where
/// the macro name became active, the location where it was undefined, etc.).
///
/// MacroDirectives, associated with an identifier, are used to model the macro
/// history. Usually a macro definition (MacroInfo) is where a macro name
/// becomes active (MacroDirective) but #pragma push_macro / pop_macro can
/// create additional DefMacroDirectives for the same MacroInfo.
class MacroDirective {
public:
enum Kind {
MD_Define,
MD_Undefine,
MD_Visibility
};
protected:
/// Previous macro directive for the same identifier, or nullptr.
MacroDirective *Previous = nullptr;
SourceLocation Loc;
/// MacroDirective kind.
unsigned MDKind : 2;
/// True if the macro directive was loaded from a PCH file.
unsigned IsFromPCH : 1;
// Used by VisibilityMacroDirective ----------------------------------------//
/// Whether the macro has public visibility (when described in a
/// module).
unsigned IsPublic : 1;
MacroDirective(Kind K, SourceLocation Loc)
: Loc(Loc), MDKind(K), IsFromPCH(false), IsPublic(true) {}
public:
Kind getKind() const { return Kind(MDKind); }
SourceLocation getLocation() const { return Loc; }
/// Set previous definition of the macro with the same name.
void setPrevious(MacroDirective *Prev) { Previous = Prev; }
/// Get previous definition of the macro with the same name.
const MacroDirective *getPrevious() const { return Previous; }
/// Get previous definition of the macro with the same name.
MacroDirective *getPrevious() { return Previous; }
/// Return true if the macro directive was loaded from a PCH file.
bool isFromPCH() const { return IsFromPCH; }
void setIsFromPCH() { IsFromPCH = true; }
class DefInfo {
DefMacroDirective *DefDirective = nullptr;
SourceLocation UndefLoc;
bool IsPublic = true;
public:
DefInfo() = default;
DefInfo(DefMacroDirective *DefDirective, SourceLocation UndefLoc,
bool isPublic)
: DefDirective(DefDirective), UndefLoc(UndefLoc), IsPublic(isPublic) {}
const DefMacroDirective *getDirective() const { return DefDirective; }
DefMacroDirective *getDirective() { return DefDirective; }
inline SourceLocation getLocation() const;
inline MacroInfo *getMacroInfo();
const MacroInfo *getMacroInfo() const {
return const_cast<DefInfo *>(this)->getMacroInfo();
}
SourceLocation getUndefLocation() const { return UndefLoc; }
bool isUndefined() const { return UndefLoc.isValid(); }
bool isPublic() const { return IsPublic; }
bool isValid() const { return DefDirective != nullptr; }
bool isInvalid() const { return !isValid(); }
explicit operator bool() const { return isValid(); }
inline DefInfo getPreviousDefinition();
const DefInfo getPreviousDefinition() const {
return const_cast<DefInfo *>(this)->getPreviousDefinition();
}
};
/// Traverses the macro directives history and returns the next
/// macro definition directive along with info about its undefined location
/// (if there is one) and if it is public or private.
DefInfo getDefinition();
const DefInfo getDefinition() const {
return const_cast<MacroDirective *>(this)->getDefinition();
}
bool isDefined() const {
if (const DefInfo Def = getDefinition())
return !Def.isUndefined();
return false;
}
const MacroInfo *getMacroInfo() const {
return getDefinition().getMacroInfo();
}
MacroInfo *getMacroInfo() { return getDefinition().getMacroInfo(); }
/// Find macro definition active in the specified source location. If
/// this macro was not defined there, return NULL.
const DefInfo findDirectiveAtLoc(SourceLocation L,
const SourceManager &SM) const;
void dump() const;
static bool classof(const MacroDirective *) { return true; }
};
/// A directive for a defined macro or a macro imported from a module.
class DefMacroDirective : public MacroDirective {
MacroInfo *Info;
public:
DefMacroDirective(MacroInfo *MI, SourceLocation Loc)
: MacroDirective(MD_Define, Loc), Info(MI) {
assert(MI && "MacroInfo is null");
}
explicit DefMacroDirective(MacroInfo *MI)
: DefMacroDirective(MI, MI->getDefinitionLoc()) {}
/// The data for the macro definition.
const MacroInfo *getInfo() const { return Info; }
MacroInfo *getInfo() { return Info; }
static bool classof(const MacroDirective *MD) {
return MD->getKind() == MD_Define;
}
static bool classof(const DefMacroDirective *) { return true; }
};
/// A directive for an undefined macro.
class UndefMacroDirective : public MacroDirective {
public:
explicit UndefMacroDirective(SourceLocation UndefLoc)
: MacroDirective(MD_Undefine, UndefLoc) {
assert(UndefLoc.isValid() && "Invalid UndefLoc!");
}
static bool classof(const MacroDirective *MD) {
return MD->getKind() == MD_Undefine;
}
static bool classof(const UndefMacroDirective *) { return true; }
};
/// A directive for setting the module visibility of a macro.
class VisibilityMacroDirective : public MacroDirective {
public:
explicit VisibilityMacroDirective(SourceLocation Loc, bool Public)
: MacroDirective(MD_Visibility, Loc) {
IsPublic = Public;
}
/// Determine whether this macro is part of the public API of its
/// module.
bool isPublic() const { return IsPublic; }
static bool classof(const MacroDirective *MD) {
return MD->getKind() == MD_Visibility;
}
static bool classof(const VisibilityMacroDirective *) { return true; }
};
inline SourceLocation MacroDirective::DefInfo::getLocation() const {
if (isInvalid())
return {};
return DefDirective->getLocation();
}
inline MacroInfo *MacroDirective::DefInfo::getMacroInfo() {
if (isInvalid())
return nullptr;
return DefDirective->getInfo();
}
inline MacroDirective::DefInfo
MacroDirective::DefInfo::getPreviousDefinition() {
if (isInvalid() || DefDirective->getPrevious() == nullptr)
return {};
return DefDirective->getPrevious()->getDefinition();
}
/// Represents a macro directive exported by a module.
///
/// There's an instance of this class for every macro #define or #undef that is
/// the final directive for a macro name within a module. These entities also
/// represent the macro override graph.
///
/// These are stored in a FoldingSet in the preprocessor.
class ModuleMacro : public llvm::FoldingSetNode {
friend class Preprocessor;
/// The name defined by the macro.
IdentifierInfo *II;
/// The body of the #define, or nullptr if this is a #undef.
MacroInfo *Macro;
/// The module that exports this macro.
Module *OwningModule;
/// The number of module macros that override this one.
unsigned NumOverriddenBy = 0;
/// The number of modules whose macros are directly overridden by this one.
unsigned NumOverrides;
ModuleMacro(Module *OwningModule, IdentifierInfo *II, MacroInfo *Macro,
ArrayRef<ModuleMacro *> Overrides)
: II(II), Macro(Macro), OwningModule(OwningModule),
NumOverrides(Overrides.size()) {
std::copy(Overrides.begin(), Overrides.end(),
reinterpret_cast<ModuleMacro **>(this + 1));
}
public:
static ModuleMacro *create(Preprocessor &PP, Module *OwningModule,
IdentifierInfo *II, MacroInfo *Macro,
ArrayRef<ModuleMacro *> Overrides);
void Profile(llvm::FoldingSetNodeID &ID) const {
return Profile(ID, OwningModule, II);
}
static void Profile(llvm::FoldingSetNodeID &ID, Module *OwningModule,
const IdentifierInfo *II) {
ID.AddPointer(OwningModule);
ID.AddPointer(II);
}
/// Get the name of the macro.
IdentifierInfo *getName() const { return II; }
/// Get the ID of the module that exports this macro.
Module *getOwningModule() const { return OwningModule; }
/// Get definition for this exported #define, or nullptr if this
/// represents a #undef.
MacroInfo *getMacroInfo() const { return Macro; }
/// Iterators over the overridden module IDs.
/// \{
using overrides_iterator = ModuleMacro *const *;
overrides_iterator overrides_begin() const {
return reinterpret_cast<overrides_iterator>(this + 1);
}
overrides_iterator overrides_end() const {
return overrides_begin() + NumOverrides;
}
ArrayRef<ModuleMacro *> overrides() const {
return llvm::ArrayRef(overrides_begin(), overrides_end());
}
/// \}
/// Get the number of macros that override this one.
unsigned getNumOverridingMacros() const { return NumOverriddenBy; }
};
/// A description of the current definition of a macro.
///
/// The definition of a macro comprises a set of (at least one) defining
/// entities, which are either local MacroDirectives or imported ModuleMacros.
class MacroDefinition {
llvm::PointerIntPair<DefMacroDirective *, 1, bool> LatestLocalAndAmbiguous;
ArrayRef<ModuleMacro *> ModuleMacros;
public:
MacroDefinition() = default;
MacroDefinition(DefMacroDirective *MD, ArrayRef<ModuleMacro *> MMs,
bool IsAmbiguous)
: LatestLocalAndAmbiguous(MD, IsAmbiguous), ModuleMacros(MMs) {}
/// Determine whether there is a definition of this macro.
explicit operator bool() const {
return getLocalDirective() || !ModuleMacros.empty();
}
/// Get the MacroInfo that should be used for this definition.
MacroInfo *getMacroInfo() const {
if (!ModuleMacros.empty())
return ModuleMacros.back()->getMacroInfo();
if (auto *MD = getLocalDirective())
return MD->getMacroInfo();
return nullptr;
}
/// \c true if the definition is ambiguous, \c false otherwise.
bool isAmbiguous() const { return LatestLocalAndAmbiguous.getInt(); }
/// Get the latest non-imported, non-\#undef'd macro definition
/// for this macro.
DefMacroDirective *getLocalDirective() const {
return LatestLocalAndAmbiguous.getPointer();
}
/// Get the active module macros for this macro.
ArrayRef<ModuleMacro *> getModuleMacros() const { return ModuleMacros; }
template <typename Fn> void forAllDefinitions(Fn F) const {
if (auto *MD = getLocalDirective())
F(MD->getMacroInfo());
for (auto *MM : getModuleMacros())
F(MM->getMacroInfo());
}
};
} // namespace clang
#endif // LLVM_CLANG_LEX_MACROINFO_H