path: root/lib/AST/DeclBase.cpp

//===--- DeclBase.cpp - Declaration AST Node Implementation ---------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Decl and DeclContext classes.
//
//===----------------------------------------------------------------------===//

#include "clang/AST/DeclBase.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/Type.h"
#include "llvm/ADT/DenseMap.h"
#include <algorithm>
#include <functional>
#include <vector>
using namespace clang;

//===----------------------------------------------------------------------===//
//  Statistics
//===----------------------------------------------------------------------===//

#define DECL(Derived, Base) static int n##Derived##s = 0;
#include "clang/AST/DeclNodes.def"

static bool StatSwitch = false;

// This keeps track of all decl attributes. Since so few decls have attrs, we
// keep them in a hash map instead of wasting space in the Decl class.
typedef llvm::DenseMap<const Decl*, Attr*> DeclAttrMapTy;

static DeclAttrMapTy *DeclAttrs = 0;

const char *Decl::getDeclKindName() const {
  switch (DeclKind) {
  default: assert(0 && "Declaration not in DeclNodes.def!");
#define DECL(Derived, Base) case Derived: return #Derived;
#include "clang/AST/DeclNodes.def"
  }
}

const char *DeclContext::getDeclKindName() const {
  switch (DeclKind) {
  default: assert(0 && "Declaration context not in DeclNodes.def!");
#define DECL(Derived, Base) case Decl::Derived: return #Derived;
#include "clang/AST/DeclNodes.def"
  }
}

bool Decl::CollectingStats(bool Enable) {
  if (Enable)
    StatSwitch = true;
  return StatSwitch;
}

void Decl::PrintStats() {
  fprintf(stderr, "*** Decl Stats:\n");
  
  int totalDecls = 0;
#define DECL(Derived, Base) totalDecls += n##Derived##s;
#include "clang/AST/DeclNodes.def"
  fprintf(stderr, "  %d decls total.\n", totalDecls);
 
  int totalBytes = 0;
#define DECL(Derived, Base)                                             \
  if (n##Derived##s > 0) {                                              \
    totalBytes += (int)(n##Derived##s * sizeof(Derived##Decl));         \
    fprintf(stderr, "    %d " #Derived " decls, %d each (%d bytes)\n",  \
            n##Derived##s, (int)sizeof(Derived##Decl),                  \
            (int)(n##Derived##s * sizeof(Derived##Decl)));              \
  }
#include "clang/AST/DeclNodes.def"
  
  fprintf(stderr, "Total bytes = %d\n", totalBytes);
}

void Decl::addDeclKind(Kind k) {
  switch (k) {
  default: assert(0 && "Declaration not in DeclNodes.def!");
#define DECL(Derived, Base) case Derived: ++n##Derived##s; break;
#include "clang/AST/DeclNodes.def"
  }
}

//===----------------------------------------------------------------------===//
// Decl Implementation
//===----------------------------------------------------------------------===//

void Decl::setDeclContext(DeclContext *DC) {
  if (isOutOfSemaDC())
    delete getMultipleDC();
  
  DeclCtx = reinterpret_cast<uintptr_t>(DC);
}

void Decl::setLexicalDeclContext(DeclContext *DC) {
  if (DC == getLexicalDeclContext())
    return;

  if (isInSemaDC()) {
    MultipleDC *MDC = new MultipleDC();
    MDC->SemanticDC = getDeclContext();
    MDC->LexicalDC = DC;
    DeclCtx = reinterpret_cast<uintptr_t>(MDC) | 0x1;
  } else {
    getMultipleDC()->LexicalDC = DC;
  }
}

// Out-of-line virtual method providing a home for Decl.
Decl::~Decl() {
  if (isOutOfSemaDC())
    delete getMultipleDC();

  if (!HasAttrs)
    return;
  
  DeclAttrMapTy::iterator it = DeclAttrs->find(this);
  assert(it != DeclAttrs->end() && "No attrs found but HasAttrs is true!");

  // release attributes.
  delete it->second;
  invalidateAttrs();
}

void Decl::addAttr(Attr *NewAttr) {
  if (!DeclAttrs)
    DeclAttrs = new DeclAttrMapTy();
  
  Attr *&ExistingAttr = (*DeclAttrs)[this];

  NewAttr->setNext(ExistingAttr);
  ExistingAttr = NewAttr;
  
  HasAttrs = true;
}

void Decl::invalidateAttrs() {
  if (!HasAttrs) return;

  HasAttrs = false;
  (*DeclAttrs)[this] = 0;
  DeclAttrs->erase(this);

  if (DeclAttrs->empty()) {
    delete DeclAttrs;
    DeclAttrs = 0;
  }
}

const Attr *Decl::getAttrs() const {
  if (!HasAttrs)
    return 0;
  
  return (*DeclAttrs)[this];
}

void Decl::swapAttrs(Decl *RHS) {
  bool HasLHSAttr = this->HasAttrs;
  bool HasRHSAttr = RHS->HasAttrs;
  
  // Usually, neither decl has attrs, nothing to do.
  if (!HasLHSAttr && !HasRHSAttr) return;
  
  // If 'this' has no attrs, swap the other way.
  if (!HasLHSAttr)
    return RHS->swapAttrs(this);
  
  // Handle the case when both decls have attrs.
  if (HasRHSAttr) {
    std::swap((*DeclAttrs)[this], (*DeclAttrs)[RHS]);
    return;
  }
  
  // Otherwise, LHS has an attr and RHS doesn't.
  (*DeclAttrs)[RHS] = (*DeclAttrs)[this];
  (*DeclAttrs).erase(this);
  this->HasAttrs = false;
  RHS->HasAttrs = true;
}


void Decl::Destroy(ASTContext& C) {
#if 0
  // FIXME: Once ownership is fully understood, we can enable this code
  if (DeclContext *DC = dyn_cast<DeclContext>(this))
    DC->decls_begin()->Destroy(C);

  // Observe the unrolled recursion.  By setting N->NextDeclInScope = 0x0
  // within the loop, only the Destroy method for the first Decl
  // will deallocate all of the Decls in a chain.
  
  Decl* N = NextDeclInScope;
  
  while (N) {
    Decl* Tmp = N->NextDeclInScope;
    N->NextDeclInScope = 0;
    N->Destroy(C);
    N = Tmp;
  }  

  this->~Decl();
  C.Deallocate((void *)this);
#endif
}

Decl *Decl::castFromDeclContext (const DeclContext *D) {
  Decl::Kind DK = D->getDeclKind();
  switch(DK) {
#define DECL_CONTEXT(Name) \
    case Decl::Name:     \
      return static_cast<Name##Decl*>(const_cast<DeclContext*>(D));
#define DECL_CONTEXT_BASE(Name)
#include "clang/AST/DeclNodes.def"
    default:
#define DECL_CONTEXT_BASE(Name)                                   \
      if (DK >= Decl::Name##First && DK <= Decl::Name##Last)    \
        return static_cast<Name##Decl*>(const_cast<DeclContext*>(D));
#include "clang/AST/DeclNodes.def"
      assert(false && "a decl that inherits DeclContext isn't handled");
      return 0;
  }
}

DeclContext *Decl::castToDeclContext(const Decl *D) {
  Decl::Kind DK = D->getKind();
  switch(DK) {
#define DECL_CONTEXT(Name) \
    case Decl::Name:     \
      return static_cast<Name##Decl*>(const_cast<Decl*>(D));
#define DECL_CONTEXT_BASE(Name)
#include "clang/AST/DeclNodes.def"
    default:
#define DECL_CONTEXT_BASE(Name)                                   \
      if (DK >= Decl::Name##First && DK <= Decl::Name##Last)    \
        return static_cast<Name##Decl*>(const_cast<Decl*>(D));
#include "clang/AST/DeclNodes.def"
      assert(false && "a decl that inherits DeclContext isn't handled");
      return 0;
  }
}

//===----------------------------------------------------------------------===//
// DeclContext Implementation
//===----------------------------------------------------------------------===//

bool DeclContext::classof(const Decl *D) {
  switch (D->getKind()) {
#define DECL_CONTEXT(Name) case Decl::Name:
#define DECL_CONTEXT_BASE(Name)
#include "clang/AST/DeclNodes.def"
      return true;
    default:
#define DECL_CONTEXT_BASE(Name)                   \
      if (D->getKind() >= Decl::Name##First &&  \
          D->getKind() <= Decl::Name##Last)     \
        return true;
#include "clang/AST/DeclNodes.def"
      return false;
  }
}

// FIXME: We really want to use a DenseSet here to eliminate the
// redundant storage of the declaration names, but (1) it doesn't give
// us the ability to search based on DeclarationName, (2) we really
// need something more like a DenseMultiSet, and (3) it's
// implemented in terms of DenseMap anyway. However, this data
// structure is really space-inefficient, so we'll have to do
// something.
typedef llvm::DenseMap<DeclarationName, std::vector<NamedDecl*> >
  StoredDeclsMap;

DeclContext::~DeclContext() {
  unsigned Size = LookupPtr.getInt();
  if (Size == LookupIsMap) {
    StoredDeclsMap *Map = static_cast<StoredDeclsMap*>(LookupPtr.getPointer());
    delete Map;
  } else {
    NamedDecl **Array = static_cast<NamedDecl**>(LookupPtr.getPointer());
    delete [] Array;
  <