libdw/memory-access.h - platform/external/elfutils - Git at Google

 /* Unaligned memory access functionality.
    Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005 Red Hat, Inc.
    This file is part of Red Hat elfutils.
    Written by Ulrich Drepper <drepper@redhat.com>, 2001.

    Red Hat elfutils is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by the
    Free Software Foundation; version 2 of the License.

    Red Hat elfutils is distributed in the hope that it will be useful, but
    WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    General Public License for more details.

    You should have received a copy of the GNU General Public License along
    with Red Hat elfutils; if not, write to the Free Software Foundation,
    Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.

    In addition, as a special exception, Red Hat, Inc. gives You the
    additional right to link the code of Red Hat elfutils with code licensed
    under any Open Source Initiative certified open source license
    (http://www.opensource.org/licenses/index.php) which requires the
    distribution of source code with any binary distribution and to
    distribute linked combinations of the two.  Non-GPL Code permitted under
    this exception must only link to the code of Red Hat elfutils through
    those well defined interfaces identified in the file named EXCEPTION
    found in the source code files (the "Approved Interfaces").  The files
    of Non-GPL Code may instantiate templates or use macros or inline
    functions from the Approved Interfaces without causing the resulting
    work to be covered by the GNU General Public License.  Only Red Hat,
    Inc. may make changes or additions to the list of Approved Interfaces.
    Red Hat's grant of this exception is conditioned upon your not adding
    any new exceptions.  If you wish to add a new Approved Interface or
    exception, please contact Red Hat.  You must obey the GNU General Public
    License in all respects for all of the Red Hat elfutils code and other
    code used in conjunction with Red Hat elfutils except the Non-GPL Code
    covered by this exception.  If you modify this file, you may extend this
    exception to your version of the file, but you are not obligated to do
    so.  If you do not wish to provide this exception without modification,
    you must delete this exception statement from your version and license
    this file solely under the GPL without exception.

    Red Hat elfutils is an included package of the Open Invention Network.
    An included package of the Open Invention Network is a package for which
    Open Invention Network licensees cross-license their patents.  No patent
    license is granted, either expressly or impliedly, by designation as an
    included package.  Should you wish to participate in the Open Invention
    Network licensing program, please visit www.openinventionnetwork.com
    <http://www.openinventionnetwork.com>.  */

 #ifndef _MEMORY_ACCESS_H
 #define _MEMORY_ACCESS_H 1

 #include <byteswap.h>
 #include <limits.h>
 #include <stdint.h>


 /* Number decoding macros.  See 7.6 Variable Length Data.  */

 #define get_uleb128_step(var, addr, nth, break)				      \
     __b = *(addr)++;							      \
     var |= (uintmax_t) (__b & 0x7f) << (nth * 7);			      \
     if (likely ((__b & 0x80) == 0))					      \
       break

 #define get_uleb128(var, addr)						      \
   do {									      \
     unsigned char __b;							      \
     var = 0;								      \
     get_uleb128_step (var, addr, 0, break);				      \
     var = __libdw_get_uleb128 (var, 1, &(addr));			      \
   } while (0)

 #define get_uleb128_rest_return(var, i, addrp)				      \
   do {									      \
     for (; i < 10; ++i)							      \
       {									      \
 	get_uleb128_step (var, *addrp, i, return var);			      \
       }									      \
     /* Other implementations set VALUE to UINT_MAX in this		      \
        case.  So we better do this as well.  */				      \
     return UINT64_MAX;							      \
   } while (0)

 /* The signed case is similar, but we sign-extend the result.  */

 #define get_sleb128_step(var, addr, nth, break)				      \
     __b = *(addr)++;							      \
     _v |= (uint64_t) (__b & 0x7f) << (nth * 7);				      \
     if (likely ((__b & 0x80) == 0))					      \
       {									      \
 	var = (_v << (64 - (nth * 7) - 7) >> (64 - (nth * 7) - 7));	      \
         break;					 			      \
       }									      \
     else do {} while (0)

 #define get_sleb128(var, addr)						      \
   do {									      \
     unsigned char __b;							      \
     int64_t _v = 0;							      \
     get_sleb128_step (var, addr, 0, break);				      \
     var = __libdw_get_sleb128 (_v, 1, &(addr));				      \
   } while (0)

 #define get_sleb128_rest_return(var, i, addrp)				      \
   do {									      \
     for (; i < 9; ++i)							      \
       {									      \
 	get_sleb128_step (var, *addrp, i, return var);			      \
       }									      \
     /* Other implementations set VALUE to INT_MAX in this		      \
        case.  So we better do this as well.  */				      \
     return INT64_MAX;							      \
   } while (0)

 #ifdef IS_LIBDW
 extern uint64_t __libdw_get_uleb128 (uint64_t acc, unsigned int i,
 				     const unsigned char **addrp)
      internal_function attribute_hidden;
 extern int64_t __libdw_get_sleb128 (int64_t acc, unsigned int i,
 				    const unsigned char **addrp)
      internal_function attribute_hidden;
 #else
 static uint64_t
 __attribute__ ((unused))
 __libdw_get_uleb128 (uint64_t acc, unsigned int i, const unsigned char **addrp)
 {
   unsigned char __b;
   get_uleb128_rest_return (acc, i, addrp);
 }
 static int64_t
 __attribute__ ((unused))
 __libdw_get_sleb128 (int64_t acc, unsigned int i, const unsigned char **addrp)
 {
   unsigned char __b;
   int64_t _v = acc;
   get_sleb128_rest_return (acc, i, addrp);
 }
 #endif


 /* We use simple memory access functions in case the hardware allows it.
    The caller has to make sure we don't have alias problems.  */
 #if ALLOW_UNALIGNED

 # define read_2ubyte_unaligned(Dbg, Addr) \
   (unlikely ((Dbg)->other_byte_order)					      \
    ? bswap_16 (*((const uint16_t *) (Addr)))				      \
    : *((const uint16_t *) (Addr)))
 # define read_2sbyte_unaligned(Dbg, Addr) \
   (unlikely ((Dbg)->other_byte_order)					      \
    ? (int16_t) bswap_16 (*((const int16_t *) (Addr)))			      \
    : *((const int16_t *) (Addr)))

 # define read_4ubyte_unaligned_noncvt(Addr) \
    *((const uint32_t *) (Addr))
 # define read_4ubyte_unaligned(Dbg, Addr) \
   (unlikely ((Dbg)->other_byte_order)					      \
    ? bswap_32 (*((const uint32_t *) (Addr)))				      \
    : *((const uint32_t *) (Addr)))
 # define read_4sbyte_unaligned(Dbg, Addr) \
   (unlikely ((Dbg)->other_byte_order)					      \
    ? (int32_t) bswap_32 (*((const int32_t *) (Addr)))			      \
    : *((const int32_t *) (Addr)))

 # define read_8ubyte_unaligned(Dbg, Addr) \
   (unlikely ((Dbg)->other_byte_order)					      \
    ? bswap_64 (*((const uint64_t *) (Addr)))				      \
    : *((const uint64_t *) (Addr)))
 # define read_8sbyte_unaligned(Dbg, Addr) \
   (unlikely ((Dbg)->other_byte_order)					      \
    ? (int64_t) bswap_64 (*((const int64_t *) (Addr)))			      \
    : *((const int64_t *) (Addr)))

 #else

 union unaligned
   {
     void *p;
     uint16_t u2;
     uint32_t u4;
     uint64_t u8;
     int16_t s2;
     int32_t s4;
     int64_t s8;
   } __attribute__ ((packed));

 static inline uint16_t
 read_2ubyte_unaligned (Dwarf *dbg, const void *p)
 {
   const union unaligned *up = p;
   if (dbg->other_byte_order)
     return bswap_16 (up->u2);
   return up->u2;
 }
 static inline int16_t
 read_2sbyte_unaligned (Dwarf *dbg, const void *p)
 {
   const union unaligned *up = p;
   if (dbg->other_byte_order)
     return (int16_t) bswap_16 (up->u2);
   return up->s2;
 }

 static inline uint32_t
 read_4ubyte_unaligned_noncvt (const void *p)
 {
   const union unaligned *up = p;
   return up->u4;
 }
 static inline uint32_t
 read_4ubyte_unaligned (Dwarf *dbg, const void *p)
 {
   const union unaligned *up = p;
   if (dbg->other_byte_order)
     return bswap_32 (up->u4);
   return up->u4;
 }
 static inline int32_t
 read_4sbyte_unaligned (Dwarf *dbg, const void *p)
 {
   const union unaligned *up = p;
   if (dbg->other_byte_order)
     return (int32_t) bswap_32 (up->u4);
   return up->s4;
 }

 static inline uint64_t
 read_8ubyte_unaligned (Dwarf *dbg, const void *p)
 {
   const union unaligned *up = p;
   if (dbg->other_byte_order)
     return bswap_64 (up->u8);
   return up->u8;
 }
 static inline int64_t
 read_8sbyte_unaligned (Dwarf *dbg, const void *p)
 {
   const union unaligned *up = p;
   if (dbg->other_byte_order)
     return (int64_t) bswap_64 (up->u8);
   return up->s8;
 }

 #endif	/* allow unaligned */


 #define read_2ubyte_unaligned_inc(Dbg, Addr) \
   ({ uint16_t t_ = read_2ubyte_unaligned (Dbg, Addr);			      \
      Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 2);		      \
      t_; })
 #define read_2sbyte_unaligned_inc(Dbg, Addr) \
   ({ int16_t t_ = read_2sbyte_unaligned (Dbg, Addr);			      \
      Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 2);		      \
      t_; })

 #define read_4ubyte_unaligned_inc(Dbg, Addr) \
   ({ uint32_t t_ = read_4ubyte_unaligned (Dbg, Addr);			      \
      Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 4);		      \
      t_; })
 #define read_4sbyte_unaligned_inc(Dbg, Addr) \
   ({ int32_t t_ = read_4sbyte_unaligned (Dbg, Addr);			      \
      Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 4);		      \
      t_; })

 #define read_8ubyte_unaligned_inc(Dbg, Addr) \
   ({ uint64_t t_ = read_8ubyte_unaligned (Dbg, Addr);			      \
      Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 8);		      \
      t_; })
 #define read_8sbyte_unaligned_inc(Dbg, Addr) \
   ({ int64_t t_ = read_8sbyte_unaligned (Dbg, Addr);			      \
      Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 8);		      \
      t_; })

 #endif	/* memory-access.h */
	/* Unaligned memory access functionality.
	Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005 Red Hat, Inc.
	This file is part of Red Hat elfutils.
	Written by Ulrich Drepper <drepper@redhat.com>, 2001.

	Red Hat elfutils is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by the
	Free Software Foundation; version 2 of the License.

	Red Hat elfutils is distributed in the hope that it will be useful, but
	WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	General Public License for more details.

	You should have received a copy of the GNU General Public License along
	with Red Hat elfutils; if not, write to the Free Software Foundation,
	Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.

	In addition, as a special exception, Red Hat, Inc. gives You the
	additional right to link the code of Red Hat elfutils with code licensed
	under any Open Source Initiative certified open source license
	(http://www.opensource.org/licenses/index.php) which requires the
	distribution of source code with any binary distribution and to
	distribute linked combinations of the two. Non-GPL Code permitted under
	this exception must only link to the code of Red Hat elfutils through
	those well defined interfaces identified in the file named EXCEPTION
	found in the source code files (the "Approved Interfaces"). The files
	of Non-GPL Code may instantiate templates or use macros or inline
	functions from the Approved Interfaces without causing the resulting
	work to be covered by the GNU General Public License. Only Red Hat,
	Inc. may make changes or additions to the list of Approved Interfaces.
	Red Hat's grant of this exception is conditioned upon your not adding
	any new exceptions. If you wish to add a new Approved Interface or
	exception, please contact Red Hat. You must obey the GNU General Public
	License in all respects for all of the Red Hat elfutils code and other
	code used in conjunction with Red Hat elfutils except the Non-GPL Code
	covered by this exception. If you modify this file, you may extend this
	exception to your version of the file, but you are not obligated to do
	so. If you do not wish to provide this exception without modification,
	you must delete this exception statement from your version and license
	this file solely under the GPL without exception.

	Red Hat elfutils is an included package of the Open Invention Network.
	An included package of the Open Invention Network is a package for which
	Open Invention Network licensees cross-license their patents. No patent
	license is granted, either expressly or impliedly, by designation as an
	included package. Should you wish to participate in the Open Invention
	Network licensing program, please visit www.openinventionnetwork.com
	<http://www.openinventionnetwork.com>. */

	#ifndef _MEMORY_ACCESS_H
	#define _MEMORY_ACCESS_H 1

	#include <byteswap.h>
	#include <limits.h>
	#include <stdint.h>


	/* Number decoding macros. See 7.6 Variable Length Data. */

	#define get_uleb128_step(var, addr, nth, break) \
	__b = *(addr)++; \
	var \|= (uintmax_t) (__b & 0x7f) << (nth * 7); \
	if (likely ((__b & 0x80) == 0)) \
	break

	#define get_uleb128(var, addr) \
	do { \
	unsigned char __b; \
	var = 0; \
	get_uleb128_step (var, addr, 0, break); \
	var = __libdw_get_uleb128 (var, 1, &(addr)); \
	} while (0)

	#define get_uleb128_rest_return(var, i, addrp) \
	do { \
	for (; i < 10; ++i) \
	{ \
	get_uleb128_step (var, *addrp, i, return var); \
	} \
	/* Other implementations set VALUE to UINT_MAX in this \
	case. So we better do this as well. */ \
	return UINT64_MAX; \
	} while (0)

	/* The signed case is similar, but we sign-extend the result. */

	#define get_sleb128_step(var, addr, nth, break) \
	__b = *(addr)++; \
	_v \|= (uint64_t) (__b & 0x7f) << (nth * 7); \
	if (likely ((__b & 0x80) == 0)) \
	{ \
	var = (_v << (64 - (nth * 7) - 7) >> (64 - (nth * 7) - 7)); \
	break; \
	} \
	else do {} while (0)

	#define get_sleb128(var, addr) \
	do { \
	unsigned char __b; \
	int64_t _v = 0; \
	get_sleb128_step (var, addr, 0, break); \
	var = __libdw_get_sleb128 (_v, 1, &(addr)); \
	} while (0)

	#define get_sleb128_rest_return(var, i, addrp) \
	do { \
	for (; i < 9; ++i) \
	{ \
	get_sleb128_step (var, *addrp, i, return var); \
	} \
	/* Other implementations set VALUE to INT_MAX in this \
	case. So we better do this as well. */ \
	return INT64_MAX; \
	} while (0)

	#ifdef IS_LIBDW
	extern uint64_t __libdw_get_uleb128 (uint64_t acc, unsigned int i,
	const unsigned char **addrp)
	internal_function attribute_hidden;
	extern int64_t __libdw_get_sleb128 (int64_t acc, unsigned int i,
	const unsigned char **addrp)
	internal_function attribute_hidden;
	#else
	static uint64_t
	__attribute__ ((unused))
	__libdw_get_uleb128 (uint64_t acc, unsigned int i, const unsigned char **addrp)
	{
	unsigned char __b;
	get_uleb128_rest_return (acc, i, addrp);
	}
	static int64_t
	__attribute__ ((unused))
	__libdw_get_sleb128 (int64_t acc, unsigned int i, const unsigned char **addrp)
	{
	unsigned char __b;
	int64_t _v = acc;
	get_sleb128_rest_return (acc, i, addrp);
	}
	#endif


	/* We use simple memory access functions in case the hardware allows it.
	The caller has to make sure we don't have alias problems. */
	#if ALLOW_UNALIGNED

	# define read_2ubyte_unaligned(Dbg, Addr) \
	(unlikely ((Dbg)->other_byte_order) \
	? bswap_16 (((const uint16_t ) (Addr))) \
	: ((const uint16_t ) (Addr)))
	# define read_2sbyte_unaligned(Dbg, Addr) \
	(unlikely ((Dbg)->other_byte_order) \
	? (int16_t) bswap_16 (((const int16_t ) (Addr))) \
	: ((const int16_t ) (Addr)))

	# define read_4ubyte_unaligned_noncvt(Addr) \
	((const uint32_t ) (Addr))
	# define read_4ubyte_unaligned(Dbg, Addr) \
	(unlikely ((Dbg)->other_byte_order) \
	? bswap_32 (((const uint32_t ) (Addr))) \
	: ((const uint32_t ) (Addr)))
	# define read_4sbyte_unaligned(Dbg, Addr) \
	(unlikely ((Dbg)->other_byte_order) \
	? (int32_t) bswap_32 (((const int32_t ) (Addr))) \
	: ((const int32_t ) (Addr)))

	# define read_8ubyte_unaligned(Dbg, Addr) \
	(unlikely ((Dbg)->other_byte_order) \
	? bswap_64 (((const uint64_t ) (Addr))) \
	: ((const uint64_t ) (Addr)))
	# define read_8sbyte_unaligned(Dbg, Addr) \
	(unlikely ((Dbg)->other_byte_order) \
	? (int64_t) bswap_64 (((const int64_t ) (Addr))) \
	: ((const int64_t ) (Addr)))

	#else

	union unaligned
	{
	void *p;
	uint16_t u2;
	uint32_t u4;
	uint64_t u8;
	int16_t s2;
	int32_t s4;
	int64_t s8;
	} __attribute__ ((packed));

	static inline uint16_t
	read_2ubyte_unaligned (Dwarf dbg, const void p)
	{
	const union unaligned *up = p;
	if (dbg->other_byte_order)
	return bswap_16 (up->u2);
	return up->u2;
	}
	static inline int16_t
	read_2sbyte_unaligned (Dwarf dbg, const void p)
	{
	const union unaligned *up = p;
	if (dbg->other_byte_order)
	return (int16_t) bswap_16 (up->u2);
	return up->s2;
	}

	static inline uint32_t
	read_4ubyte_unaligned_noncvt (const void *p)
	{
	const union unaligned *up = p;
	return up->u4;
	}
	static inline uint32_t
	read_4ubyte_unaligned (Dwarf dbg, const void p)
	{
	const union unaligned *up = p;
	if (dbg->other_byte_order)
	return bswap_32 (up->u4);
	return up->u4;
	}
	static inline int32_t
	read_4sbyte_unaligned (Dwarf dbg, const void p)
	{
	const union unaligned *up = p;
	if (dbg->other_byte_order)
	return (int32_t) bswap_32 (up->u4);
	return up->s4;
	}

	static inline uint64_t
	read_8ubyte_unaligned (Dwarf dbg, const void p)
	{
	const union unaligned *up = p;
	if (dbg->other_byte_order)
	return bswap_64 (up->u8);
	return up->u8;
	}
	static inline int64_t
	read_8sbyte_unaligned (Dwarf dbg, const void p)
	{
	const union unaligned *up = p;
	if (dbg->other_byte_order)
	return (int64_t) bswap_64 (up->u8);
	return up->s8;
	}

	#endif /* allow unaligned */


	#define read_2ubyte_unaligned_inc(Dbg, Addr) \
	({ uint16_t t_ = read_2ubyte_unaligned (Dbg, Addr); \
	Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 2); \
	t_; })
	#define read_2sbyte_unaligned_inc(Dbg, Addr) \
	({ int16_t t_ = read_2sbyte_unaligned (Dbg, Addr); \
	Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 2); \
	t_; })

	#define read_4ubyte_unaligned_inc(Dbg, Addr) \
	({ uint32_t t_ = read_4ubyte_unaligned (Dbg, Addr); \
	Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 4); \
	t_; })
	#define read_4sbyte_unaligned_inc(Dbg, Addr) \
	({ int32_t t_ = read_4sbyte_unaligned (Dbg, Addr); \
	Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 4); \
	t_; })

	#define read_8ubyte_unaligned_inc(Dbg, Addr) \
	({ uint64_t t_ = read_8ubyte_unaligned (Dbg, Addr); \
	Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 8); \
	t_; })
	#define read_8sbyte_unaligned_inc(Dbg, Addr) \
	({ int64_t t_ = read_8sbyte_unaligned (Dbg, Addr); \
	Addr = (__typeof (Addr)) (((uintptr_t) (Addr)) + 8); \
	t_; })

	#endif /* memory-access.h */