Type-mem.h

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 * See the dyninst/COPYRIGHT file for copyright information.
 * 
 * We provide the Paradyn Tools (below described as "Paradyn")
 * on an AS IS basis, and do not warrant its validity or performance.
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 * other person or entity with proprietary rights in Paradyn) are
 * under no obligation to provide either maintenance services,
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 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
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 */

#if !defined(TYPE_MEM_H_)
#define TYPE_MEM_H_

#include "symtabAPI/h/Type.h"
#include "boost/static_assert.hpp"

namespace Dyninst {
  namespace SymtabAPI {
    extern std::map<void *, size_t> type_memory;
  }
}

using namespace Dyninst;
using namespace SymtabAPI;

template<class T>
T *upgradePlaceholder(Type *placeholder, T *new_type)
{
  void *mem = (void *) placeholder;
  assert(type_memory.count(mem));
  size_t size = type_memory[mem];

  assert(sizeof(T) < size);
  memset(mem, 0, size);

  T *ret = new(mem) T();
  assert(mem == (void *) ret);
  *ret = *new_type;
  return ret;
}

template<class T>
T* typeCollection::addOrUpdateType(T *type) 
{
    //Instanciating this function for 'Type' would be a mistake, which
    //the following assert tries to guard against.  If you trigger this,
    //then a caller to this function is likely using 'Type'.  Change
    //this to a more specific call, e.g. typeFunction instead of Type
    BOOST_STATIC_ASSERT(sizeof(T) != sizeof(Type));

    Type *existingType = findTypeLocal(type->getID());
    if (!existingType) 
    {
        if ( type->getName() != "" ) 
        {
            typesByName[ type->getName() ] = type;
        }
        typesByID[ type->getID() ] = type;
        type->incrRefCount();
        return type;
    }

    /* Multiple inclusions of the same object file can result
       in us parsing the same module types repeatedly. GCC does this
       with some of its internal routines */

    T *existingT = dynamic_cast<T*>(existingType);
    if (existingT && (*existingT == *type)) 
    {
        return (T*) existingType;
    }

    if (existingType->getDataClass() == dataUnknownType) 
    {
        upgradePlaceholder(existingType, type);
    } 
    else 
    {
        /* Merge the type information. */
        existingType->merge(type);
    }

    /* The type may have gained a name. */
    if ( existingType->getName() != "") 
    {
        if (typesByName.find(existingType->getName()) != typesByName.end()) 
        {
            if (typesByName[ existingType->getName() ] != existingType) 
            {
                typesByName[ existingType->getName() ]->decrRefCount();
                typesByName[ existingType->getName() ] = existingType;
                existingType->incrRefCount();
            }
        } 
        else 
        {
            typesByName[ existingType->getName() ] = existingType;
            existingType->incrRefCount();
        }
    }

    /* Tell the parser to update its type pointer. */
    return (T*) existingType;
} /* end addOrUpdateType() */


#endif