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Diffstat (limited to 'src/libdw/memory-access.h')
| -rw-r--r-- | src/libdw/memory-access.h | 315 |
1 files changed, 315 insertions, 0 deletions
diff --git a/src/libdw/memory-access.h b/src/libdw/memory-access.h new file mode 100644 index 00000000..b7799e92 --- /dev/null +++ b/src/libdw/memory-access.h @@ -0,0 +1,315 @@ +/* Unaligned memory access functionality. + Copyright (C) 2000-2010 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); \ + } \ + __b = *(*addrp)++; \ + if (likely ((__b & 0x80) == 0)) \ + return var | ((uint64_t) __b << 63); \ + else \ + /* 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 inline 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 inline 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)); + +# define read_2ubyte_unaligned(Dbg, Addr) \ + read_2ubyte_unaligned_1 ((Dbg)->other_byte_order, (Addr)) +# define read_2sbyte_unaligned(Dbg, Addr) \ + read_2sbyte_unaligned_1 ((Dbg)->other_byte_order, (Addr)) +# define read_4ubyte_unaligned(Dbg, Addr) \ + read_4ubyte_unaligned_1 ((Dbg)->other_byte_order, (Addr)) +# define read_4sbyte_unaligned(Dbg, Addr) \ + read_4sbyte_unaligned_1 ((Dbg)->other_byte_order, (Addr)) +# define read_8ubyte_unaligned(Dbg, Addr) \ + read_8ubyte_unaligned_1 ((Dbg)->other_byte_order, (Addr)) +# define read_8sbyte_unaligned(Dbg, Addr) \ + read_8sbyte_unaligned_1 ((Dbg)->other_byte_order, (Addr)) + +static inline uint16_t +read_2ubyte_unaligned_1 (bool other_byte_order, const void *p) +{ + const union unaligned *up = p; + if (unlikely (other_byte_order)) + return bswap_16 (up->u2); + return up->u2; +} +static inline int16_t +read_2sbyte_unaligned_1 (bool other_byte_order, const void *p) +{ + const union unaligned *up = p; + if (unlikely (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_1 (bool other_byte_order, const void *p) +{ + const union unaligned *up = p; + if (unlikely (other_byte_order)) + return bswap_32 (up->u4); + return up->u4; +} +static inline int32_t +read_4sbyte_unaligned_1 (bool other_byte_order, const void *p) +{ + const union unaligned *up = p; + if (unlikely (other_byte_order)) + return (int32_t) bswap_32 (up->u4); + return up->s4; +} + +static inline uint64_t +read_8ubyte_unaligned_1 (bool other_byte_order, const void *p) +{ + const union unaligned *up = p; + if (unlikely (other_byte_order)) + return bswap_64 (up->u8); + return up->u8; +} +static inline int64_t +read_8sbyte_unaligned_1 (bool other_byte_order, const void *p) +{ + const union unaligned *up = p; + if (unlikely (other_byte_order)) + return (int64_t) bswap_64 (up->u8); + return up->s8; +} + +#endif /* allow unaligned */ + + +#define read_ubyte_unaligned(Nbytes, Dbg, Addr) \ + ((Nbytes) == 2 ? read_2ubyte_unaligned (Dbg, Addr) \ + : (Nbytes) == 4 ? read_4ubyte_unaligned (Dbg, Addr) \ + : read_8ubyte_unaligned (Dbg, Addr)) + +#define read_sbyte_unaligned(Nbytes, Dbg, Addr) \ + ((Nbytes) == 2 ? read_2sbyte_unaligned (Dbg, Addr) \ + : (Nbytes) == 4 ? read_4sbyte_unaligned (Dbg, Addr) \ + : read_8sbyte_unaligned (Dbg, Addr)) + + +#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_; }) + + +#define read_ubyte_unaligned_inc(Nbytes, Dbg, Addr) \ + ((Nbytes) == 2 ? read_2ubyte_unaligned_inc (Dbg, Addr) \ + : (Nbytes) == 4 ? read_4ubyte_unaligned_inc (Dbg, Addr) \ + : read_8ubyte_unaligned_inc (Dbg, Addr)) + +#define read_sbyte_unaligned_inc(Nbytes, Dbg, Addr) \ + ((Nbytes) == 2 ? read_2sbyte_unaligned_inc (Dbg, Addr) \ + : (Nbytes) == 4 ? read_4sbyte_unaligned_inc (Dbg, Addr) \ + : read_8sbyte_unaligned_inc (Dbg, Addr)) + +#endif /* memory-access.h */ |