Files
swift-mirror/include/swift/AST/Attr.h
2013-11-05 15:58:19 +00:00

285 lines
8.7 KiB
C++

//===--- Attr.h - Swift Language Attribute ASTs -----------------*- C++ -*-===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2015 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See http://swift.org/LICENSE.txt for license information
// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
//
// This file defines classes related to declaration attributes.
//
//===----------------------------------------------------------------------===//
#ifndef SWIFT_ATTR_H
#define SWIFT_ATTR_H
#include "swift/Basic/Optional.h"
#include "swift/Basic/SourceLoc.h"
#include "swift/AST/Ownership.h"
#include "llvm/ADT/StringRef.h"
namespace swift {
/// The associativity of a binary operator.
enum class Associativity {
/// Non-associative operators cannot be written next to other
/// operators with the same precedence. Relational operators are
/// typically non-associative.
None,
/// Left-associative operators associate to the left if written next
/// to other left-associative operators of the same precedence.
Left,
/// Right-associative operators associate to the right if written
/// next to other right-associative operators of the same precedence.
Right
};
class InfixData {
unsigned Precedence : 8;
/// Zero if invalid, or else an Associativity+1.
unsigned InvalidOrAssoc : 8;
public:
InfixData() : Precedence(0), InvalidOrAssoc(0) {}
InfixData(unsigned char prec, Associativity assoc)
: Precedence(prec), InvalidOrAssoc(unsigned(assoc) + 1) {}
bool isValid() const { return InvalidOrAssoc != 0; }
Associativity getAssociativity() const {
assert(isValid());
return Associativity(InvalidOrAssoc - 1);
}
bool isLeftAssociative() const {
return getAssociativity() == Associativity::Left;
}
bool isRightAssociative() const {
return getAssociativity() == Associativity::Right;
}
bool isNonAssociative() const {
return getAssociativity() == Associativity::None;
}
unsigned getPrecedence() const {
assert(isValid());
return Precedence;
}
friend bool operator==(InfixData L, InfixData R) {
return L.Precedence == R.Precedence
&& L.InvalidOrAssoc == R.InvalidOrAssoc;
}
friend bool operator!=(InfixData L, InfixData R) {
return !operator==(L, R);
}
};
/// ABI resilience. Language structures are resilient if the details
/// of their implementation may be changed without requiring
/// associated code to be reprocessed. Different structures are resilient
/// in different ways. For example:
/// - A resilient type does not have a statically fixed size or layout.
/// - A resilient variable must be accessed with getters and setters, even if
/// none are defined for it now.
/// - A resilient function may not be inlined.
///
/// In general, resilience is inherited from the lexical context. For
/// example, a variable declared in a fragile struct is implicitly fragile.
///
/// Some language structures, like tuples, are never themselves
/// resilient (although they may be defined in terms of resilient
/// types). Additionally, code distributed with the component
/// defining a resilient structure need not actually use resilience
/// boundaries.
enum class Resilience : unsigned char {
Default,
/// Inherently fragile language structures are not only resilient,
/// but they have never been exposed as resilient. This permits
/// certain kinds of optimizations that are not otherwise possible
/// because of the need for backward compatibility.
InherentlyFragile,
/// Fragile language structures are non-resilient. They may have
/// been resilient at some point in the past, however.
Fragile,
/// Everything else is resilient. Resilience means different things
/// on different kinds of objects.
Resilient
};
enum class AbstractCC : unsigned char;
// Define enumerators for each attribute, e.g. AK_weak.
enum AttrKind {
#define ATTR(X) AK_##X,
#include "swift/AST/Attr.def"
AK_Count
};
// Define enumerators for each type attribute, e.g. TAK_weak.
enum TypeAttrKind {
#define ATTR(X)
#define TYPE_ATTR(X) TAK_##X,
#include "swift/AST/Attr.def"
TAK_Count
};
/// TypeAttributes - These are attributes that may be applied to types.
class TypeAttributes {
// Get a SourceLoc for every possible attribute that can be parsed in source.
// the presence of the attribute is indicated by its location being set.
SourceLoc AttrLocs[TAK_Count];
public:
/// AtLoc - This is the location of the first '@' in the attribute specifier.
/// If this is an empty attribute specifier, then this will be an invalid loc.
SourceLoc AtLoc;
Optional<AbstractCC> cc = Nothing;
TypeAttributes() {}
bool isValid() const { return AtLoc.isValid(); }
void clearAttribute(TypeAttrKind A) {
AttrLocs[A] = SourceLoc();
}
bool has(TypeAttrKind A) const {
return getLoc(A).isValid();
}
SourceLoc getLoc(TypeAttrKind A) const {
return AttrLocs[A];
}
void setAttr(TypeAttrKind A, SourceLoc L) {
assert(!L.isInvalid() && "Cannot clear attribute with this method");
AttrLocs[A] = L;
}
// This attribute list is empty if no attributes are specified. Note that
// the presence of the leading @ is not enough to tell, because we want
// clients to be able to remove attributes they process until they get to
// an empty list.
bool empty() const {
for (SourceLoc elt : AttrLocs)
if (elt.isValid()) return false;
return true;
}
bool hasCC() const { return cc.hasValue(); }
AbstractCC getAbstractCC() const { return *cc; }
bool hasOwnership() const { return getOwnership() != Ownership::Strong; }
Ownership getOwnership() const {
if (has(TAK_sil_weak)) return Ownership::Weak;
if (has(TAK_sil_unowned)) return Ownership::Unowned;
return Ownership::Strong;
}
void clearOwnership() {
clearAttribute(TAK_sil_weak);
clearAttribute(TAK_sil_unowned);
}
};
/// DeclAttributes - These are attributes that may be applied to declarations.
class DeclAttributes {
// Get a SourceLoc for every possible attribute that can be parsed in source.
// the presence of the attribute is indicated by its location being set.
SourceLoc AttrLocs[AK_Count];
bool HasAttr[AK_Count] = { false };
public:
/// AtLoc - This is the location of the first '@' in the attribute specifier.
/// If this is an empty attribute specifier, then this will be an invalid loc.
SourceLoc AtLoc;
StringRef AsmName;
DeclAttributes() {}
bool isValid() const { return AtLoc.isValid(); }
void clearAttribute(AttrKind A) {
AttrLocs[A] = SourceLoc();
HasAttr[A] = false;
}
bool has(AttrKind A) const {
return HasAttr[A];
}
SourceLoc getLoc(AttrKind A) const {
return AttrLocs[A];
}
void setAttr(AttrKind A, SourceLoc L) {
AttrLocs[A] = L;
HasAttr[A] = true;
}
// This attribute list is empty if no attributes are specified. Note that
// the presence of the leading @ is not enough to tell, because we want
// clients to be able to remove attributes they process until they get to
// an empty list.
bool empty() const {
for (bool elt : HasAttr)
if (elt) return false;
return true;
}
bool isNoReturn() const { return has(AK_noreturn); }
bool isAssignment() const { return has(AK_assignment); }
bool isConversion() const { return has(AK_conversion); }
bool isTransparent() const {return has(AK_transparent);}
bool isPrefix() const { return has(AK_prefix); }
bool isPostfix() const { return has(AK_postfix); }
bool isInfix() const { return has(AK_infix); }
bool isObjC() const { return has(AK_objc); }
bool isIBOutlet() const { return has(AK_iboutlet); }
bool isIBAction() const { return has(AK_ibaction); }
bool isClassProtocol() const { return has(AK_class_protocol); }
bool isWeak() const { return has(AK_weak); }
bool isUnowned() const { return has(AK_unowned); }
bool isExported() const { return has(AK_exported); }
bool isOptional() const { return has(AK_optional); }
Resilience getResilienceKind() const {
if (has(AK_resilient))
return Resilience::Resilient;
if (has(AK_fragile))
return Resilience::Fragile;
if (has(AK_born_fragile))
return Resilience::InherentlyFragile;
return Resilience::Default;
}
bool hasOwnership() const { return isWeak() || isUnowned(); }
Ownership getOwnership() const {
if (isWeak()) return Ownership::Weak;
if (isUnowned()) return Ownership::Unowned;
return Ownership::Strong;
}
void clearOwnership() {
clearAttribute(AK_weak);
clearAttribute(AK_unowned);
}
};
} // end namespace swift
#endif