diff -r 1af5c1be89f8 -r 92d87f2e53c2 tools/elf4rom/libs/dwarf-20071209/libdwarf/dwarf_leb.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/tools/elf4rom/libs/dwarf-20071209/libdwarf/dwarf_leb.c Fri Jan 15 09:07:44 2010 +0000 @@ -0,0 +1,149 @@ +/* + + Copyright (C) 2000,2004 Silicon Graphics, Inc. All Rights Reserved. + + This program is free software; you can redistribute it and/or modify it + under the terms of version 2.1 of the GNU Lesser General Public License + as published by the Free Software Foundation. + + This program is distributed in the hope that it would be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + + Further, this software is distributed without any warranty that it is + free of the rightful claim of any third person regarding infringement + or the like. Any license provided herein, whether implied or + otherwise, applies only to this software file. Patent licenses, if + any, provided herein do not apply to combinations of this program with + other software, or any other product whatsoever. + + You should have received a copy of the GNU Lesser General Public + License along with this program; if not, write the Free Software + Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston MA 02110-1301, + USA. + + Contact information: Silicon Graphics, Inc., 1500 Crittenden Lane, + Mountain View, CA 94043, or: + + http://www.sgi.com + + For further information regarding this notice, see: + + http://oss.sgi.com/projects/GenInfo/NoticeExplan + +*/ + + + +#include "config.h" +#include "dwarf_incl.h" +#include + + +/* + decode ULEB +*/ +Dwarf_Unsigned +_dwarf_decode_u_leb128(Dwarf_Small * leb128, Dwarf_Word * leb128_length) +{ + unsigned char byte; + Dwarf_Word word_number; + Dwarf_Unsigned number; + Dwarf_Sword shift; + Dwarf_Sword byte_length; + + /* The following unrolls-the-loop for the first few bytes and + unpacks into 32 bits to make this as fast as possible. + word_number is assumed big enough that the shift has a defined + result. */ + if ((*leb128 & 0x80) == 0) { + if (leb128_length != NULL) + *leb128_length = 1; + return (*leb128); + } else if ((*(leb128 + 1) & 0x80) == 0) { + if (leb128_length != NULL) + *leb128_length = 2; + + word_number = *leb128 & 0x7f; + word_number |= (*(leb128 + 1) & 0x7f) << 7; + return (word_number); + } else if ((*(leb128 + 2) & 0x80) == 0) { + if (leb128_length != NULL) + *leb128_length = 3; + + word_number = *leb128 & 0x7f; + word_number |= (*(leb128 + 1) & 0x7f) << 7; + word_number |= (*(leb128 + 2) & 0x7f) << 14; + return (word_number); + } else if ((*(leb128 + 3) & 0x80) == 0) { + if (leb128_length != NULL) + *leb128_length = 4; + + word_number = *leb128 & 0x7f; + word_number |= (*(leb128 + 1) & 0x7f) << 7; + word_number |= (*(leb128 + 2) & 0x7f) << 14; + word_number |= (*(leb128 + 3) & 0x7f) << 21; + return (word_number); + } + + /* The rest handles long numbers Because the 'number' may be larger + than the default int/unsigned, we must cast the 'byte' before + the shift for the shift to have a defined result. */ + number = 0; + shift = 0; + byte_length = 1; + byte = *(leb128); + for (;;) { + number |= ((Dwarf_Unsigned) (byte & 0x7f)) << shift; + + if ((byte & 0x80) == 0) { + if (leb128_length != NULL) + *leb128_length = byte_length; + return (number); + } + shift += 7; + + byte_length++; + ++leb128; + byte = *leb128; + } +} + +#define BITSINBYTE 8 + +/* + decode SLEB +*/ +Dwarf_Signed +_dwarf_decode_s_leb128(Dwarf_Small * leb128, Dwarf_Word * leb128_length) +{ + Dwarf_Signed number = 0; + Dwarf_Bool sign = 0; + Dwarf_Sword shift = 0; + unsigned char byte = *leb128; + Dwarf_Sword byte_length = 1; + + /* byte_length being the number of bytes of data absorbed so far in + turning the leb into a Dwarf_Signed. */ + + for (;;) { + sign = byte & 0x40; + number |= ((Dwarf_Signed) ((byte & 0x7f))) << shift; + shift += 7; + + if ((byte & 0x80) == 0) { + break; + } + ++leb128; + byte = *leb128; + byte_length++; + } + + if ((shift < sizeof(Dwarf_Signed) * BITSINBYTE) && sign) { + number |= -((Dwarf_Signed) 1 << shift); + } + + if (leb128_length != NULL) + *leb128_length = byte_length; + return (number); +}