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swift-mirror/lib/AST/Decl.cpp

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C++

//===--- Decl.cpp - Swift Language Decl ASTs ------------------------------===//
//
// 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 implements the Decl class and subclasses.
//
//===----------------------------------------------------------------------===//
#include "swift/AST/Decl.h"
#include "swift/AST/AST.h"
#include "swift/AST/ASTContext.h"
#include "swift/AST/ASTVisitor.h"
#include "llvm/Support/raw_ostream.h"
using namespace swift;
/// getASTContext - Return the ASTContext for a specified DeclContetx by
/// walking up to the translation unit and returning its ASTContext.
ASTContext &DeclContext::getASTContext() {
if (Module *M = dyn_cast<Module>(this))
return M->Ctx;
return getParent()->getASTContext();
}
// Only allow allocation of Decls using the allocator in ASTContext.
void *Decl::operator new(size_t Bytes, ASTContext &C,
unsigned Alignment) {
return C.Allocate(Bytes, Alignment);
}
// Only allow allocation of Modules using the allocator in ASTContext.
void *Module::operator new(size_t Bytes, ASTContext &C,
unsigned Alignment) {
return C.Allocate(Bytes, Alignment);
}
SourceLoc Decl::getLocStart() const {
switch (getKind()) {
#define DECL(NAME, X) \
case DeclKind::NAME: return cast<NAME##Decl>(this)->getLocStart();
#include "swift/AST/DeclNodes.def"
}
llvm_unreachable("Unknown decl kind");
}
/// getAliasType - Return the sugared version of this decl as a Type.
NameAliasType *TypeAliasDecl::getAliasType() const {
// Lazily create AliasTy.
if (AliasTy == 0)
AliasTy = new (getASTContext()) NameAliasType(
const_cast<TypeAliasDecl*>(this));
return AliasTy;
}
ImportDecl *ImportDecl::create(ASTContext &Ctx, DeclContext *DC,
SourceLoc ImportLoc,
ArrayRef<AccessPathElement> Path) {
void *buffer = Ctx.Allocate(sizeof(ImportDecl) +
Path.size() * sizeof(AccessPathElement),
Decl::Alignment);
return new (buffer) ImportDecl(DC, ImportLoc, Path);
}
ImportDecl::ImportDecl(DeclContext *DC, SourceLoc ImportLoc,
ArrayRef<AccessPathElement> Path)
: Decl(DeclKind::Import, DC), ImportLoc(ImportLoc),
NumPathElements(Path.size()) {
memcpy(getPathBuffer(), Path.data(), Path.size() * sizeof(AccessPathElement));
}
/// getTypeOfReference - Return the full type judgement for a non-member
/// reference to this value.
Type ValueDecl::getTypeOfReference() const {
if (isReferencedAsLValue()) {
return LValueType::get(Ty, LValueType::Qual::DefaultForVar, getASTContext());
} else {
return Ty;
}
}
/// isDefinition - Return true if this is a definition of a decl, not a
/// forward declaration (e.g. of a function) that is implemented outside of
/// the swift code.
bool ValueDecl::isDefinition() const {
switch (getKind()) {
case DeclKind::Import:
case DeclKind::Extension:
case DeclKind::PatternBinding:
case DeclKind::Subscript:
llvm_unreachable("non-value decls shouldn't get here");
case DeclKind::Func:
return cast<FuncDecl>(this)->getBody() != 0;
case DeclKind::Var:
case DeclKind::OneOfElement:
case DeclKind::TypeAlias:
return true;
}
}
bool ValueDecl::isInstanceMember() const {
DeclContext *DC = getDeclContext();
if (!isa<OneOfType>(DC) && !isa<ExtensionDecl>(DC) && !isa<ProtocolType>(DC))
return false;
// Variables in oneofs/extensions/protocols are instance members.
// FIXME: If we ever end up with static variables, we'll have to check for
// them here.
if (isa<VarDecl>(this))
return true;
// Non-static methods are instance members.
if (const FuncDecl *Func = dyn_cast<FuncDecl>(this))
return !Func->isStatic();
return false;
}
TypeAliasDecl::TypeAliasDecl(SourceLoc TypeAliasLoc, Identifier Name,
Type Underlyingty, DeclContext *DC,
bool IsModuleScope)
: ValueDecl(DeclKind::TypeAlias, DC, IsModuleScope, Name, Type()),
AliasTy(0), TypeAliasLoc(TypeAliasLoc), UnderlyingTy(Underlyingty) {
// Set the type of the TypeAlias to the right MetaTypeType.
setType(MetaTypeType::get(this));
}
void VarDecl::setProperty(ASTContext &Context, SourceLoc LBraceLoc,
FuncDecl *Get, FuncDecl *Set, SourceLoc RBraceLoc) {
assert(!GetSet && "Variable is already a property?");
void *Mem = Context.Allocate(sizeof(GetSetRecord), alignof(GetSetRecord));
GetSet = new (Mem) GetSetRecord;
GetSet->Braces = SourceRange(LBraceLoc, RBraceLoc);
GetSet->Get = Get;
GetSet->Set = Set;
if (Get)
Get->makeGetter(this);
if (Set)
Set->makeSetter(this);
}
/// getExtensionType - If this is a method in a type extension for some type,
/// return that type, otherwise return Type().
Type FuncDecl::getExtensionType() const {
DeclContext *DC = getDeclContext();
switch (DC->getContextKind()) {
case DeclContextKind::TranslationUnit:
case DeclContextKind::BuiltinModule:
case DeclContextKind::FuncExpr:
case DeclContextKind::ExplicitClosureExpr:
case DeclContextKind::ImplicitClosureExpr:
case DeclContextKind::OneOfType:
return Type();
// For extensions, it depends on whether the type has value or
// pointer semantics.
case DeclContextKind::ExtensionDecl:
return cast<ExtensionDecl>(DC)->getExtendedType();
case DeclContextKind::ProtocolType:
// FIXME: It's not really clear how protocol types should get passed.
return cast<ProtocolType>(DC);
}
llvm_unreachable("bad context kind");
}
/// computeThisType - If this is a method in a type extension for some type,
/// compute and return the type to be used for the 'this' argument of the
/// type (which varies based on whether the extended type is a reference type
/// or not), or an empty Type() if no 'this' argument should exist. This can
/// only be used after name binding has resolved types.
Type FuncDecl::computeThisType() const {
// 'static' functions have no 'this' argument.
if (isStatic()) return Type();
Type ContainerType = getExtensionType();
if (ContainerType.isNull()) return ContainerType;
if (ContainerType->hasReferenceSemantics())
return ContainerType;
// 'this' is accepts implicit l-values and doesn't force them to the heap.
return LValueType::get(ContainerType,
LValueType::Qual::Implicit | LValueType::Qual::NonHeap,
getASTContext());
}
/// getImplicitThisDecl - If this FuncDecl is a non-static method in an
/// extension context, it will have a 'this' argument. This method returns it
/// if present, or returns null if not.
VarDecl *FuncDecl::getImplicitThisDecl() {
if (isStatic()) return 0;
if (Body->getParamPatterns().empty()) return 0;
// "this" is represented as (typed_pattern (named_pattern (var_decl 'this')).
TypedPattern *TP = dyn_cast<TypedPattern>(Body->getParamPatterns()[0]);
if (TP == 0) return 0;
// The decl should be named 'this' and have no location information.
NamedPattern *NP = dyn_cast<NamedPattern>(TP->getSubPattern());
if (NP && NP->getBoundName().str() == "this" && !NP->getLoc().isValid())
return NP->getDecl();
return 0;
}
//===----------------------------------------------------------------------===//
// Decl printing.
//===----------------------------------------------------------------------===//
namespace {
/// PrintDecl - Visitor implementation of Decl::print.
class PrintDecl : public DeclVisitor<PrintDecl> {
public:
raw_ostream &OS;
unsigned Indent;
PrintDecl(raw_ostream &os, unsigned indent) : OS(os), Indent(indent) {
}
void printRec(Decl *D) { D->print(OS, Indent+2); }
void printRec(Expr *E) { E->print(OS, Indent+2); }
void printRec(Stmt *S) { S->print(OS, Indent+2); }
void printCommon(Decl *D, const char *Name) {
OS.indent(Indent) << "(" << Name;
}
void visitImportDecl(ImportDecl *ID) {
printCommon(ID, "import_decl");
OS << " '" << ID->getAccessPath()[0].first;
for (unsigned i = 1, e = ID->getAccessPath().size(); i != e; ++i)
OS << "." << ID->getAccessPath()[i].first;
OS << "')";
}
void visitExtensionDecl(ExtensionDecl *ED) {
printCommon(ED, "extension_decl");
OS << ' ';
ED->getExtendedType()->print(OS);
for (Decl *Member : ED->getMembers()) {
OS << '\n';
printRec(Member);
}
OS << ")";
}
void printDeclName(NamedDecl *D) {
if (D->getName().get())
OS << '\'' << D->getName() << '\'';
else
OS << "'anonname=" << (const void*)D << '\'';
}
void printCommon(NamedDecl *D, const char *Name) {
printCommon((Decl*)D, Name);
OS << ' ';
printDeclName(D);
}
void visitTypeAliasDecl(TypeAliasDecl *TAD) {
printCommon(TAD, "typealias");
OS << " type='";
TAD->getUnderlyingType()->print(OS);
OS << "')";
}
void printCommon(ValueDecl *VD, const char *Name) {
printCommon((NamedDecl*)VD, Name);
OS << " type='";
if (VD->hasType())
VD->getType()->print(OS);
else
OS << "<null type>";
OS << '\'';
if (VD->hasFixedLifetime()) OS << " hasFixedLifetime=true";
if (VD->isNeverUsedAsLValue()) OS << " neverUsedAsLValue=true";
}
void visitTranslationUnit(const TranslationUnit *TU) {
OS.indent(Indent) << "(translation_unit\n";
if (TU->Body)
printRec(TU->Body);
else
OS.indent(Indent+2) << "(null body!)";
OS << ')';
}
void visitVarDecl(VarDecl *VD) {
printCommon(VD, "var_decl");
if (VD->isProperty()) {
if (FuncDecl *Get = VD->getGetter()) {
OS << "\n";
OS.indent(Indent + 2);
OS << "get = ";
printRec(Get);
}
if (FuncDecl *Set = VD->getSetter()) {
OS << "\n";
OS.indent(Indent + 2);
OS << "set = ";
printRec(Set);
}
}
OS << ')';
}
void visitFuncDecl(FuncDecl *FD) {
printCommon(FD, "func_decl");
if (FuncExpr *E = FD->getBody()) {
OS << '\n';
printRec(E);
}
OS << ')';
}
void visitOneOfElementDecl(OneOfElementDecl *OOED) {
printCommon(OOED, "oneof_element_decl");
OS << ')';
}
void visitPatternBindingDecl(PatternBindingDecl *PBD) {
printCommon(PBD, "pattern_binding_decl");
if (PBD->getInit()) {
OS << '\n';
printRec(PBD->getInit());
}
}
void visitSubscriptDecl(SubscriptDecl *SD) {
printCommon(SD, "subscript_decl");
if (FuncDecl *Get = SD->getGetter()) {
OS << "\n";
OS.indent(Indent + 2);
OS << "get = ";
printRec(Get);
}
if (FuncDecl *Set = SD->getSetter()) {
OS << "\n";
OS.indent(Indent + 2);
OS << "set = ";
printRec(Set);
}
OS << ')';
}
};
} // end anonymous namespace.
void Decl::print(raw_ostream &OS, unsigned Indent) const {
PrintDecl(OS, Indent).visit(const_cast<Decl*>(this));
}
void Decl::dump() const {
print(llvm::errs());
llvm::errs() << '\n';
}
void TranslationUnit::dump() const {
PrintDecl(llvm::errs(), 0).visitTranslationUnit(this);
llvm::errs() << '\n';
}