1 /* BFD backend for CRIS a.out binaries. 2 Copyright (C) 2000-2016 Free Software Foundation, Inc. 3 Contributed by Axis Communications AB. 4 Written by Hans-Peter Nilsson. 5 6 This file is part of BFD, the Binary File Descriptor library. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 3 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 21 MA 02110-1301, USA. */ 22 23 /* See info in the file PORTING for documentation of these macros and 24 functions. Beware; some of the information there is outdated. */ 25 26 #define N_HEADER_IN_TEXT(x) 0 27 #define N_TXTOFF(x) 32 28 #define ENTRY_CAN_BE_ZERO 29 #define TEXT_START_ADDR 0 30 31 /* Without reading symbols to get the text start symbol, there is no way 32 to know where the text segment starts in an a.out file. Defaulting to 33 anything as constant as TEXT_START_ADDR is bad. But we can guess from 34 the entry point, which is usually within the first 64k of the text 35 segment. We also assume here that the text segment is 64k-aligned. 36 FIXME: It is also wrong to assume that data and bss follow immediately 37 after text, but with those, we don't have any choice besides reading 38 symbol info, and luckily there's no pressing need for correctness for 39 those vma:s at this time. */ 40 #define N_TXTADDR(x) ((x)->a_entry & ~(bfd_vma) 0xffff) 41 42 /* If you change this to 4, you can not link to an address N*4+2. */ 43 #define SEGMENT_SIZE 2 44 45 /* For some reason, if the a.out file has Z_MAGIC, then 46 adata(abfd).exec_bytes_size is not used, but rather 47 adata(abfd).zmagic_disk_block_size, even though the exec_header is 48 *not* included in the text segment. A simple workaround is to 49 #define ZMAGIC_DISK_BLOCK_SIZE, which is used if defined; otherwise 50 TARGET_PAGE_SIZE is used. */ 51 #define ZMAGIC_DISK_BLOCK_SIZE N_TXTOFF (0) 52 53 /* It seems odd at first to set a page-size this low, but gives greater 54 freedom in where things can be linked. The drawback is that you have 55 to set alignment and padding in linker scripts. */ 56 #define TARGET_PAGE_SIZE SEGMENT_SIZE 57 #define TARGETNAME "a.out-cris" 58 59 /* The definition here seems not used; just provided as a convention. */ 60 #define DEFAULT_ARCH bfd_arch_cris 61 62 /* Do not "beautify" the CONCAT* macro args. Traditional C will not 63 remove whitespace added here, and thus will fail to concatenate 64 the tokens. */ 65 #define MY(OP) CONCAT2 (cris_aout_,OP) 66 #define NAME(x, y) CONCAT3 (cris_aout,_32_,y) 67 68 #include "sysdep.h" 69 #include "bfd.h" 70 71 /* Version 1 of the header. */ 72 #define MY_exec_hdr_flags 1 73 74 #define MY_write_object_contents MY (write_object_contents) 75 static bfd_boolean MY (write_object_contents) (bfd *); 76 77 /* Forward this, so we can use a pointer to it in PARAMS. */ 78 struct reloc_ext_external; 79 80 #define MY_swap_ext_reloc_out MY (swap_ext_reloc_out) 81 static void MY (swap_ext_reloc_out) (bfd *, arelent *, struct reloc_ext_external *); 82 83 #define MY_swap_ext_reloc_in MY (swap_ext_reloc_in) 84 static void MY (swap_ext_reloc_in) (bfd *, struct reloc_ext_external *, 85 arelent *, asymbol **, bfd_size_type); 86 87 #define MY_set_sizes MY (set_sizes) 88 static bfd_boolean MY (set_sizes) (bfd *); 89 90 /* To set back reloc_size to ext, we make MY (set_sizes) be called 91 through this construct. Note that MY_set_arch_mach is only called 92 through SET_ARCH_MACH. The default bfd_default_set_arch_mach will 93 not call set_sizes. */ 94 95 #define MY_set_arch_mach NAME (aout, set_arch_mach) 96 #define SET_ARCH_MACH(BFD, EXECP) \ 97 MY_set_arch_mach (BFD, DEFAULT_ARCH, N_MACHTYPE (EXECP)) 98 99 /* These macros describe the binary layout of the reloc information we 100 use in a file. */ 101 #define RELOC_EXT_BITS_EXTERN_LITTLE 0x80 102 #define RELOC_EXT_BITS_TYPE_LITTLE 3 103 #define RELOC_EXT_BITS_TYPE_SH_LITTLE 0 104 105 #ifndef MY_get_section_contents 106 #define MY_get_section_contents aout_32_get_section_contents 107 #endif 108 109 #define MACHTYPE_OK(mtype) ((mtype) == M_CRIS) 110 111 /* Include generic functions (some are overridden above). */ 112 #include "aout32.c" 113 #include "aout-target.h" 114 115 /* We need our own version to set header flags. */ 116 117 static bfd_boolean 118 MY (write_object_contents) (bfd *abfd) 119 { 120 struct external_exec exec_bytes; 121 struct internal_exec *execp = exec_hdr (abfd); 122 123 /* We set the reloc type to RELOC_EXT_SIZE, although setting it at all 124 seems unnecessary when inspecting as and ld behavior (not an 125 exhaustive inspection). The default write_object_contents 126 definition sets RELOC_EXT_SIZE, so we follow suite and set it too. */ 127 obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE; 128 129 /* Setting N_SET_MACHTYPE and using N_SET_FLAGS is not performed by 130 the default definition. */ 131 if (bfd_get_arch (abfd) == bfd_arch_cris) 132 N_SET_MACHTYPE (execp, M_CRIS); 133 134 N_SET_FLAGS (execp, aout_backend_info (abfd)->exec_hdr_flags); 135 136 WRITE_HEADERS (abfd, execp); 137 138 return TRUE; 139 } 140 141 /* We need our own for these reasons: 142 - Assert that a normal 8, 16 or 32 reloc is output. 143 - Fix what seems to be a weak-bug (perhaps there for valid reasons). */ 144 145 static void 146 MY (swap_ext_reloc_out) (bfd *abfd, 147 arelent *g, 148 struct reloc_ext_external *natptr) 149 { 150 int r_index; 151 int r_extern; 152 unsigned int r_type; 153 bfd_vma r_addend; 154 asymbol *sym = *(g->sym_ptr_ptr); 155 asection *output_section = sym->section->output_section; 156 157 PUT_WORD (abfd, g->address, natptr->r_address); 158 159 r_type = (unsigned int) g->howto->type; 160 161 r_addend = g->addend; 162 if ((sym->flags & BSF_SECTION_SYM) != 0) 163 r_addend += (*(g->sym_ptr_ptr))->section->output_section->vma; 164 165 /* If this relocation is relative to a symbol then set the 166 r_index to the symbols index, and the r_extern bit. 167 168 Absolute symbols can come in in two ways, either as an offset 169 from the abs section, or as a symbol which has an abs value. 170 check for that here. */ 171 172 if (bfd_is_abs_section (bfd_get_section (sym))) 173 { 174 r_extern = 0; 175 r_index = N_ABS; 176 } 177 else if ((sym->flags & BSF_SECTION_SYM) == 0) 178 { 179 if (bfd_is_und_section (bfd_get_section (sym)) 180 /* Remember to check for weak symbols; they count as global. */ 181 || (sym->flags & (BSF_GLOBAL | BSF_WEAK)) != 0) 182 r_extern = 1; 183 else 184 r_extern = 0; 185 r_index = (*(g->sym_ptr_ptr))->KEEPIT; 186 } 187 else 188 { 189 /* Just an ordinary section. */ 190 r_extern = 0; 191 r_index = output_section->target_index; 192 } 193 194 /* The relocation type is the same as the canonical ones, but only 195 the first 3 are used: RELOC_8, RELOC_16, RELOC_32. 196 We may change this later, but assert this for the moment. */ 197 if (r_type > 2) 198 { 199 (*_bfd_error_handler) (_("%s: Invalid relocation type exported: %d"), 200 bfd_get_filename (abfd), r_type); 201 202 bfd_set_error (bfd_error_wrong_format); 203 } 204 205 /* Now the fun stuff. */ 206 natptr->r_index[2] = r_index >> 16; 207 natptr->r_index[1] = r_index >> 8; 208 natptr->r_index[0] = r_index; 209 natptr->r_type[0] = 210 (r_extern ? RELOC_EXT_BITS_EXTERN_LITTLE : 0) 211 | (r_type << RELOC_EXT_BITS_TYPE_SH_LITTLE); 212 213 PUT_WORD (abfd, r_addend, natptr->r_addend); 214 } 215 216 /* We need our own to assert that a normal 8, 16 or 32 reloc is input. */ 217 218 static void 219 MY (swap_ext_reloc_in) (bfd *abfd, 220 struct reloc_ext_external *bytes, 221 arelent *cache_ptr, 222 asymbol **symbols, 223 bfd_size_type symcount) 224 { 225 unsigned int r_index; 226 int r_extern; 227 unsigned int r_type; 228 struct aoutdata *su = &(abfd->tdata.aout_data->a); 229 230 cache_ptr->address = (GET_SWORD (abfd, bytes->r_address)); 231 232 /* Now the fun stuff. */ 233 r_index = (bytes->r_index[2] << 16) 234 | (bytes->r_index[1] << 8) 235 | bytes->r_index[0]; 236 r_extern = (0 != (bytes->r_type[0] & RELOC_EXT_BITS_EXTERN_LITTLE)); 237 r_type = ((bytes->r_type[0]) >> RELOC_EXT_BITS_TYPE_SH_LITTLE) 238 & RELOC_EXT_BITS_TYPE_LITTLE; 239 240 if (r_type > 2) 241 { 242 (*_bfd_error_handler) (_("%B: Invalid relocation type imported: %d"), 243 abfd, r_type); 244 245 bfd_set_error (bfd_error_wrong_format); 246 } 247 248 cache_ptr->howto = howto_table_ext + r_type; 249 250 if (r_extern && r_index > symcount) 251 { 252 (*_bfd_error_handler) 253 (_("%B: Bad relocation record imported: %d"), abfd, r_index); 254 255 bfd_set_error (bfd_error_wrong_format); 256 257 /* We continue, so we can catch further errors. */ 258 r_extern = 0; 259 r_index = N_ABS; 260 } 261 262 /* Magically uses r_extern, symbols etc. Ugly, but it's what's in the 263 default. */ 264 MOVE_ADDRESS (GET_SWORD (abfd, bytes->r_addend)); 265 } 266 267 /* We use the same as the default, except that we also set 268 "obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE;", to avoid changing 269 NAME (aout, set_arch_mach) in aoutx. */ 270 271 static bfd_boolean 272 MY (set_sizes) (bfd *abfd) 273 { 274 /* Just as the default in aout-target.h (with some #ifdefs folded)... */ 275 276 adata (abfd).page_size = TARGET_PAGE_SIZE; 277 adata (abfd).segment_size = SEGMENT_SIZE; 278 adata (abfd).zmagic_disk_block_size = ZMAGIC_DISK_BLOCK_SIZE; 279 adata (abfd).exec_bytes_size = EXEC_BYTES_SIZE; 280 281 /* ... except for that we have the extended reloc. The alternative 282 would be to add a check on bfd_arch_cris in NAME (aout, 283 set_arch_mach) in aoutx.h, but I don't want to do that since 284 target-specific things should not be added there. */ 285 286 obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE; 287 288 return TRUE; 289 } 290
