1 /* ARC-specific support for 32-bit ELF 2 Copyright (C) 1994-2014 Free Software Foundation, Inc. 3 Contributed by Doug Evans (dje (at) cygnus.com). 4 5 This file is part of BFD, the Binary File Descriptor library. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 20 MA 02110-1301, USA. */ 21 22 #include "sysdep.h" 23 #include "bfd.h" 24 #include "libbfd.h" 25 #include "elf-bfd.h" 26 #include "elf/arc.h" 27 #include "libiberty.h" 28 29 /* Try to minimize the amount of space occupied by relocation tables 30 on the ROM (not that the ROM won't be swamped by other ELF overhead). */ 31 32 #define USE_REL 1 33 34 static bfd_reloc_status_type 35 arc_elf_b22_pcrel (bfd * abfd, 36 arelent * reloc_entry, 37 asymbol * symbol, 38 void * data, 39 asection * input_section, 40 bfd * output_bfd, 41 char ** error_message) 42 { 43 /* If linking, back up the final symbol address by the address of the 44 reloc. This cannot be accomplished by setting the pcrel_offset 45 field to TRUE, as bfd_install_relocation will detect this and refuse 46 to install the offset in the first place, but bfd_perform_relocation 47 will still insist on removing it. */ 48 if (output_bfd == NULL) 49 reloc_entry->addend -= reloc_entry->address; 50 51 /* Fall through to the default elf reloc handler. */ 52 return bfd_elf_generic_reloc (abfd, reloc_entry, symbol, data, 53 input_section, output_bfd, error_message); 54 } 55 56 static reloc_howto_type elf_arc_howto_table[] = 57 { 58 /* This reloc does nothing. */ 59 HOWTO (R_ARC_NONE, /* Type. */ 60 0, /* Rightshift. */ 61 2, /* Size (0 = byte, 1 = short, 2 = long). */ 62 32, /* Bitsize. */ 63 FALSE, /* PC_relative. */ 64 0, /* Bitpos. */ 65 complain_overflow_bitfield, /* Complain_on_overflow. */ 66 bfd_elf_generic_reloc, /* Special_function. */ 67 "R_ARC_NONE", /* Name. */ 68 TRUE, /* Partial_inplace. */ 69 0, /* Src_mask. */ 70 0, /* Dst_mask. */ 71 FALSE), /* PCrel_offset. */ 72 73 /* A standard 32 bit relocation. */ 74 HOWTO (R_ARC_32, /* Type. */ 75 0, /* Rightshift. */ 76 2, /* Size (0 = byte, 1 = short, 2 = long). */ 77 32, /* Bitsize. */ 78 FALSE, /* PC_relative. */ 79 0, /* Bitpos. */ 80 complain_overflow_bitfield, /* Complain_on_overflow. */ 81 bfd_elf_generic_reloc, /* Special_function. */ 82 "R_ARC_32", /* Name. */ 83 TRUE, /* Partial_inplace. */ 84 0xffffffff, /* Src_mask. */ 85 0xffffffff, /* Dst_mask. */ 86 FALSE), /* PCrel_offset. */ 87 88 /* A 26 bit absolute branch, right shifted by 2. */ 89 HOWTO (R_ARC_B26, /* Type. */ 90 2, /* Rightshift. */ 91 2, /* Size (0 = byte, 1 = short, 2 = long). */ 92 26, /* Bitsize. */ 93 FALSE, /* PC_relative. */ 94 0, /* Bitpos. */ 95 complain_overflow_bitfield, /* Complain_on_overflow. */ 96 bfd_elf_generic_reloc, /* Special_function. */ 97 "R_ARC_B26", /* Name. */ 98 TRUE, /* Partial_inplace. */ 99 0x00ffffff, /* Src_mask. */ 100 0x00ffffff, /* Dst_mask. */ 101 FALSE), /* PCrel_offset. */ 102 103 /* A relative 22 bit branch; bits 21-2 are stored in bits 26-7. */ 104 HOWTO (R_ARC_B22_PCREL, /* Type. */ 105 2, /* Rightshift. */ 106 2, /* Size (0 = byte, 1 = short, 2 = long). */ 107 22, /* Bitsize. */ 108 TRUE, /* PC_relative. */ 109 7, /* Bitpos. */ 110 complain_overflow_signed, /* Complain_on_overflow. */ 111 arc_elf_b22_pcrel, /* Special_function. */ 112 "R_ARC_B22_PCREL", /* Name. */ 113 TRUE, /* Partial_inplace. */ 114 0x07ffff80, /* Src_mask. */ 115 0x07ffff80, /* Dst_mask. */ 116 FALSE), /* PCrel_offset. */ 117 }; 118 119 /* Map BFD reloc types to ARC ELF reloc types. */ 120 121 struct arc_reloc_map 122 { 123 bfd_reloc_code_real_type bfd_reloc_val; 124 unsigned char elf_reloc_val; 125 }; 126 127 static const struct arc_reloc_map arc_reloc_map[] = 128 { 129 { BFD_RELOC_NONE, R_ARC_NONE, }, 130 { BFD_RELOC_32, R_ARC_32 }, 131 { BFD_RELOC_CTOR, R_ARC_32 }, 132 { BFD_RELOC_ARC_B26, R_ARC_B26 }, 133 { BFD_RELOC_ARC_B22_PCREL, R_ARC_B22_PCREL }, 134 }; 135 136 static reloc_howto_type * 137 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED, 138 bfd_reloc_code_real_type code) 139 { 140 unsigned int i; 141 142 for (i = ARRAY_SIZE (arc_reloc_map); i--;) 143 if (arc_reloc_map[i].bfd_reloc_val == code) 144 return elf_arc_howto_table + arc_reloc_map[i].elf_reloc_val; 145 146 return NULL; 147 } 148 149 static reloc_howto_type * 150 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, 151 const char *r_name) 152 { 153 unsigned int i; 154 155 for (i = 0; 156 i < sizeof (elf_arc_howto_table) / sizeof (elf_arc_howto_table[0]); 157 i++) 158 if (elf_arc_howto_table[i].name != NULL 159 && strcasecmp (elf_arc_howto_table[i].name, r_name) == 0) 160 return &elf_arc_howto_table[i]; 161 162 return NULL; 163 } 164 165 /* Set the howto pointer for an ARC ELF reloc. */ 166 167 static void 168 arc_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED, 169 arelent *cache_ptr, 170 Elf_Internal_Rela *dst) 171 { 172 unsigned int r_type; 173 174 r_type = ELF32_R_TYPE (dst->r_info); 175 BFD_ASSERT (r_type < (unsigned int) R_ARC_max); 176 cache_ptr->howto = &elf_arc_howto_table[r_type]; 177 } 178 179 /* Set the right machine number for an ARC ELF file. */ 180 181 static bfd_boolean 182 arc_elf_object_p (bfd *abfd) 183 { 184 unsigned int mach = bfd_mach_arc_6; 185 186 if (elf_elfheader(abfd)->e_machine == EM_ARC) 187 { 188 unsigned long arch = elf_elfheader (abfd)->e_flags & EF_ARC_MACH; 189 190 switch (arch) 191 { 192 case E_ARC_MACH_ARC5: 193 mach = bfd_mach_arc_5; 194 break; 195 default: 196 case E_ARC_MACH_ARC6: 197 mach = bfd_mach_arc_6; 198 break; 199 case E_ARC_MACH_ARC7: 200 mach = bfd_mach_arc_7; 201 break; 202 case E_ARC_MACH_ARC8: 203 mach = bfd_mach_arc_8; 204 break; 205 } 206 } 207 return bfd_default_set_arch_mach (abfd, bfd_arch_arc, mach); 208 } 209 210 /* The final processing done just before writing out an ARC ELF object file. 211 This gets the ARC architecture right based on the machine number. */ 212 213 static void 214 arc_elf_final_write_processing (bfd *abfd, 215 bfd_boolean linker ATTRIBUTE_UNUSED) 216 { 217 unsigned long val; 218 219 switch (bfd_get_mach (abfd)) 220 { 221 case bfd_mach_arc_5: 222 val = E_ARC_MACH_ARC5; 223 break; 224 default: 225 case bfd_mach_arc_6: 226 val = E_ARC_MACH_ARC6; 227 break; 228 case bfd_mach_arc_7: 229 val = E_ARC_MACH_ARC7; 230 break; 231 case bfd_mach_arc_8: 232 val = E_ARC_MACH_ARC8; 233 break; 234 } 235 elf_elfheader (abfd)->e_flags &=~ EF_ARC_MACH; 236 elf_elfheader (abfd)->e_flags |= val; 237 } 238 239 #define TARGET_LITTLE_SYM arc_elf32_le_vec 240 #define TARGET_LITTLE_NAME "elf32-littlearc" 241 #define TARGET_BIG_SYM arc_elf32_be_vec 242 #define TARGET_BIG_NAME "elf32-bigarc" 243 #define ELF_ARCH bfd_arch_arc 244 #define ELF_MACHINE_CODE EM_ARC 245 #define ELF_MAXPAGESIZE 0x1000 246 247 #define elf_info_to_howto 0 248 #define elf_info_to_howto_rel arc_info_to_howto_rel 249 #define elf_backend_object_p arc_elf_object_p 250 #define elf_backend_final_write_processing arc_elf_final_write_processing 251 252 #include "elf32-target.h" 253
