path: root/cpukit/include/rtems/linkersets.h

/*
 * Copyright (c) 2015, 2020 embedded brains GmbH.  All rights reserved.
 *
 *  embedded brains GmbH
 *  Dornierstr. 4
 *  82178 Puchheim
 *  Germany
 *  <rtems@embedded-brains.de>
 *
 * The license and distribution terms for this file may be
 * found in the file LICENSE in this distribution or at
 * http://www.rtems.org/license/LICENSE.
 */

#ifndef _RTEMS_LINKERSET_H
#define _RTEMS_LINKERSET_H

#include <rtems/score/basedefs.h>

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

#define RTEMS_LINKER_SET_BEGIN( set ) \
  _Linker_set_##set##_begin

#define RTEMS_LINKER_SET_END( set ) \
  _Linker_set_##set##_end

/*
 * Modern GCC optimizes for speed which may insert padding between linker
 * sections that previous versions avoided. Alignment must now be explicit to
 * maintain the behavior of previous versions.
 */
#define RTEMS_LINKER_SET_ALIGN( type ) \
  RTEMS_ALIGNED( RTEMS_ALIGNOF( type ) )

#define RTEMS_LINKER_ROSET_DECLARE( set, type ) \
  extern RTEMS_LINKER_SET_ALIGN( type ) type	\
  const RTEMS_LINKER_SET_BEGIN( set )[];	\
  extern RTEMS_LINKER_SET_ALIGN( type ) type	\
  const RTEMS_LINKER_SET_END( set )[]

#define RTEMS_LINKER_ROSET( set, type ) \
  RTEMS_LINKER_SET_ALIGN( type ) type const RTEMS_LINKER_SET_BEGIN( set )[ 0 ] \
  RTEMS_SECTION( ".rtemsroset." #set ".begin" ) RTEMS_USED; \
  RTEMS_LINKER_SET_ALIGN( type ) type const RTEMS_LINKER_SET_END( set )[ 0 ] \
  RTEMS_SECTION( ".rtemsroset." #set ".end" ) RTEMS_USED

#define RTEMS_LINKER_ROSET_ITEM_ORDERED_DECLARE( set, type, item, order ) \
  extern RTEMS_LINKER_SET_ALIGN( type ) type const _Linker_set_##set##_##item \
  RTEMS_SECTION( ".rtemsroset." #set ".content.0." RTEMS_XSTRING( order ) )

#define RTEMS_LINKER_ROSET_ITEM_DECLARE( set, type, item ) \
  extern RTEMS_LINKER_SET_ALIGN( type ) type const _Linker_set_##set##_##item \
  RTEMS_SECTION( ".rtemsroset." #set ".content.1" )

#define RTEMS_LINKER_ROSET_ITEM_REFERENCE( set, type, item )	\
  static RTEMS_LINKER_SET_ALIGN( type ) type			\
  const * const _Set_reference_##set##_##item			\
  RTEMS_SECTION( ".rtemsroset.reference" ) RTEMS_USED =		\
  &_Linker_set_##set##_##item

#define RTEMS_LINKER_ROSET_ITEM_ORDERED( set, type, item, order ) \
  RTEMS_LINKER_SET_ALIGN( type ) type const _Linker_set_##set##_##item \
  RTEMS_SECTION( ".rtemsroset." #set ".content.0." RTEMS_XSTRING( order ) ) \
  RTEMS_USED

#define RTEMS_LINKER_ROSET_ITEM( set, type, item ) \
  RTEMS_LINKER_SET_ALIGN( type ) type const _Linker_set_##set##_##item \
  RTEMS_SECTION( ".rtemsroset." #set ".content.1" ) RTEMS_USED

#define RTEMS_LINKER_ROSET_CONTENT( set, decl ) \
  decl \
  RTEMS_SECTION( ".rtemsroset." #set ".content" )

#define RTEMS_LINKER_RWSET_DECLARE( set, type ) \
  extern RTEMS_LINKER_SET_ALIGN( type ) type RTEMS_LINKER_SET_BEGIN( set )[]; \
  extern RTEMS_LINKER_SET_ALIGN( type ) type RTEMS_LINKER_SET_END( set )[]

#define RTEMS_LINKER_RWSET( set, type ) \
  RTEMS_LINKER_SET_ALIGN( type ) type RTEMS_LINKER_SET_BEGIN( set )[ 0 ] \
  RTEMS_SECTION( ".rtemsrwset." #set ".begin" ) RTEMS_USED; \
  RTEMS_LINKER_SET_ALIGN( type ) type RTEMS_LINKER_SET_END( set )[ 0 ] \
  RTEMS_SECTION( ".rtemsrwset." #set ".end" ) RTEMS_USED

#define RTEMS_LINKER_RWSET_ITEM_ORDERED_DECLARE( set, type, item, order ) \
  extern RTEMS_LINKER_SET_ALIGN( type ) type _Linker_set_##set##_##item \
  RTEMS_SECTION( ".rtemsrwset." #set ".content.0." RTEMS_XSTRING( order ) )

#define RTEMS_LINKER_RWSET_ITEM_DECLARE( set, type, item ) \
  extern RTEMS_LINKER_SET_ALIGN( type ) type _Linker_set_##set##_##item \
  RTEMS_SECTION( ".rtemsrwset." #set ".content.1" )

/*
 * The .rtemsroset is here not a typo.  We must ensure that the references are
 * not a victim of the garbage collection of the linker.  Thus, we place them
 * in a dedicated area of the RTEMS read-only linker set section.
 */
#define RTEMS_LINKER_RWSET_ITEM_REFERENCE( set, type, item ) \
  static RTEMS_LINKER_SET_ALIGN( type ) type			\
  * const _Set_reference_##set##_##item				\
  RTEMS_SECTION( ".rtemsroset.reference" ) RTEMS_USED = \
  &_Linker_set_##set##_##item

#define RTEMS_LINKER_RWSET_ITEM_ORDERED( set, type, item, order ) \
  RTEMS_LINKER_SET_ALIGN( type ) type _Linker_set_##set##_##item \
  RTEMS_SECTION( ".rtemsrwset." #set ".content.0." RTEMS_XSTRING( order ) ) \
  RTEMS_USED

#define RTEMS_LINKER_RWSET_ITEM( set, type, item ) \
  RTEMS_LINKER_SET_ALIGN( type ) type _Linker_set_##set##_##item \
  RTEMS_SECTION( ".rtemsrwset." #set ".content.1" ) RTEMS_USED

#define RTEMS_LINKER_RWSET_CONTENT( set, decl ) \
  decl \
  RTEMS_SECTION( ".rtemsrwset." #set ".content" )

RTEMS_INLINE_ROUTINE uintptr_t _Linker_set_Obfuscate( const void *ptr )
{
  uintptr_t addr;

  addr = (uintptr_t) ptr;
  RTEMS_OBFUSCATE_VARIABLE( addr );

  return addr;
}

#define RTEMS_LINKER_SET_SIZE( set ) \
  ( _Linker_set_Obfuscate( RTEMS_LINKER_SET_END( set ) ) \
    - _Linker_set_Obfuscate( RTEMS_LINKER_SET_BEGIN( set ) ) )

#define RTEMS_LINKER_SET_ITEM_COUNT( set ) \
  ( RTEMS_LINKER_SET_SIZE( set ) \
    / sizeof( RTEMS_LINKER_SET_BEGIN( set )[ 0 ] ) )

#define RTEMS_LINKER_SET_IS_EMPTY( set ) \
  ( RTEMS_LINKER_SET_SIZE( set ) == 0 )

#define RTEMS_LINKER_SET_FOREACH( set, item ) \
  for ( \
    item = (void *) _Linker_set_Obfuscate( RTEMS_LINKER_SET_BEGIN( set ) ) ; \
    item != RTEMS_LINKER_SET_END( set ) ; \
    ++item \
  )

#ifdef __cplusplus
}
#endif /* __cplusplus */

#endif /* _RTEMS_LINKERSET_H */