1/* BFD backend for CRIS a.out binaries. 2 Copyright 2000, 2001, 2002, 2003, 2004, 2005 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 2 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, MA 02110-1301, USA. */ 21 22/* See info in the file PORTING for documentation of these macros and 23 functions. Beware; some of the information there is outdated. */ 24 25#define N_HEADER_IN_TEXT(x) 0 26#define N_TXTOFF(x) 32 27#define ENTRY_CAN_BE_ZERO 28#define TEXT_START_ADDR 0 29 30/* Without reading symbols to get the text start symbol, there is no way 31 to know where the text segment starts in an a.out file. Defaulting to 32 anything as constant as TEXT_START_ADDR is bad. But we can guess from 33 the entry point, which is usually within the first 64k of the text 34 segment. We also assume here that the text segment is 64k-aligned. 35 FIXME: It is also wrong to assume that data and bss follow immediately 36 after text, but with those, we don't have any choice besides reading 37 symbol info, and luckily there's no pressing need for correctness for 38 those vma:s at this time. */ 39#define N_TXTADDR(x) ((x).a_entry & ~(bfd_vma) 0xffff) 40 41/* If you change this to 4, you can not link to an address N*4+2. */ 42#define SEGMENT_SIZE 2 43 44/* For some reason, if the a.out file has Z_MAGIC, then 45 adata(abfd).exec_bytes_size is not used, but rather 46 adata(abfd).zmagic_disk_block_size, even though the exec_header is 47 *not* included in the text segment. A simple workaround is to 48 #define ZMAGIC_DISK_BLOCK_SIZE, which is used if defined; otherwise 49 TARGET_PAGE_SIZE is used. */ 50#define ZMAGIC_DISK_BLOCK_SIZE N_TXTOFF (0) 51 52/* It seems odd at first to set a page-size this low, but gives greater 53 freedom in where things can be linked. The drawback is that you have 54 to set alignment and padding in linker scripts. */ 55#define TARGET_PAGE_SIZE SEGMENT_SIZE 56#define TARGETNAME "a.out-cris" 57 58/* N_SHARED_LIB gets this reasonable default as of 1999-07-12, but we 59 have to work with 2.9.1. Note that N_SHARED_LIB is used in a 60 SUN-specific context, not applicable to CRIS. */ 61#define N_SHARED_LIB(x) 0 62 63/* The definition here seems not used; just provided as a convention. */ 64#define DEFAULT_ARCH bfd_arch_cris 65 66/* Do not "beautify" the CONCAT* macro args. Traditional C will not 67 remove whitespace added here, and thus will fail to concatenate 68 the tokens. */ 69#define MY(OP) CONCAT2 (cris_aout_,OP) 70#define NAME(x, y) CONCAT3 (cris_aout,_32_,y) 71 72#include "bfd.h" 73 74/* Version 1 of the header. */ 75#define MY_exec_hdr_flags 1 76 77#define MY_write_object_contents MY (write_object_contents) 78static bfd_boolean MY (write_object_contents) (bfd *); 79 80/* Forward this, so we can use a pointer to it in PARAMS. */ 81struct reloc_ext_external; 82 83#define MY_swap_ext_reloc_out MY (swap_ext_reloc_out) 84static void MY (swap_ext_reloc_out) (bfd *, arelent *, struct reloc_ext_external *); 85 86#define MY_swap_ext_reloc_in MY (swap_ext_reloc_in) 87static void MY (swap_ext_reloc_in) (bfd *, struct reloc_ext_external *, 88 arelent *, asymbol **, bfd_size_type); 89 90#define MY_set_sizes MY (set_sizes) 91static bfd_boolean MY (set_sizes) (bfd *); 92 93/* To set back reloc_size to ext, we make MY (set_sizes) be called 94 through this construct. Note that MY_set_arch_mach is only called 95 through SET_ARCH_MACH. The default bfd_default_set_arch_mach will 96 not call set_sizes. */ 97 98#define MY_set_arch_mach NAME (aout, set_arch_mach) 99#define SET_ARCH_MACH(BFD, EXEC) \ 100 MY_set_arch_mach (BFD, DEFAULT_ARCH, N_MACHTYPE (EXEC)) 101 102/* These macros describe the binary layout of the reloc information we 103 use in a file. */ 104#define RELOC_EXT_BITS_EXTERN_LITTLE 0x80 105#define RELOC_EXT_BITS_TYPE_LITTLE 3 106#define RELOC_EXT_BITS_TYPE_SH_LITTLE 0 107 108#ifndef MY_get_section_contents 109#define MY_get_section_contents aout_32_get_section_contents 110#endif 111 112#define MACHTYPE_OK(mtype) ((mtype) == M_CRIS) 113 114/* Include generic functions (some are overridden above). */ 115#include "aout32.c" 116#include "aout-target.h" 117 118/* We need our own version to set header flags. */ 119 120static bfd_boolean 121MY (write_object_contents) (bfd *abfd) 122{ 123 struct external_exec exec_bytes; 124 struct internal_exec *execp = exec_hdr (abfd); 125 126 /* We set the reloc type to RELOC_EXT_SIZE, although setting it at all 127 seems unnecessary when inspecting as and ld behavior (not an 128 exhaustive inspection). The default write_object_contents 129 definition sets RELOC_EXT_SIZE, so we follow suite and set it too. */ 130 obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE; 131 132 /* Setting N_SET_MACHTYPE and using N_SET_FLAGS is not performed by 133 the default definition. */ 134 if (bfd_get_arch (abfd) == bfd_arch_cris) 135 N_SET_MACHTYPE (*execp, M_CRIS); 136 137 N_SET_FLAGS (*execp, aout_backend_info (abfd)->exec_hdr_flags); 138 139 WRITE_HEADERS (abfd, execp); 140 141 return TRUE; 142} 143 144/* We need our own for these reasons: 145 - Assert that a normal 8, 16 or 32 reloc is output. 146 - Fix what seems to be a weak-bug (perhaps there for valid reasons). */ 147 148static void 149MY (swap_ext_reloc_out) (bfd *abfd, 150 arelent *g, 151 struct reloc_ext_external *natptr) 152{ 153 int r_index; 154 int r_extern; 155 unsigned int r_type; 156 bfd_vma r_addend; 157 asymbol *sym = *(g->sym_ptr_ptr); 158 asection *output_section = sym->section->output_section; 159 160 PUT_WORD (abfd, g->address, natptr->r_address); 161 162 r_type = (unsigned int) g->howto->type; 163 164 r_addend = g->addend; 165 if ((sym->flags & BSF_SECTION_SYM) != 0) 166 r_addend += (*(g->sym_ptr_ptr))->section->output_section->vma; 167 168 /* If this relocation is relative to a symbol then set the 169 r_index to the symbols index, and the r_extern bit. 170 171 Absolute symbols can come in in two ways, either as an offset 172 from the abs section, or as a symbol which has an abs value. 173 check for that here. */ 174 175 if (bfd_is_abs_section (bfd_get_section (sym))) 176 { 177 r_extern = 0; 178 r_index = N_ABS; 179 } 180 else if ((sym->flags & BSF_SECTION_SYM) == 0) 181 { 182 if (bfd_is_und_section (bfd_get_section (sym)) 183 /* Remember to check for weak symbols; they count as global. */ 184 || (sym->flags & (BSF_GLOBAL | BSF_WEAK)) != 0) 185 r_extern = 1; 186 else 187 r_extern = 0; 188 r_index = (*(g->sym_ptr_ptr))->KEEPIT; 189 } 190 else 191 { 192 /* Just an ordinary section. */ 193 r_extern = 0; 194 r_index = output_section->target_index; 195 } 196 197 /* The relocation type is the same as the canonical ones, but only 198 the first 3 are used: RELOC_8, RELOC_16, RELOC_32. 199 We may change this later, but assert this for the moment. */ 200 if (r_type > 2) 201 { 202 (*_bfd_error_handler) (_("%s: Invalid relocation type exported: %d"), 203 bfd_get_filename (abfd), r_type); 204 205 bfd_set_error (bfd_error_wrong_format); 206 } 207 208 /* Now the fun stuff. */ 209 natptr->r_index[2] = r_index >> 16; 210 natptr->r_index[1] = r_index >> 8; 211 natptr->r_index[0] = r_index; 212 natptr->r_type[0] = 213 (r_extern ? RELOC_EXT_BITS_EXTERN_LITTLE : 0) 214 | (r_type << RELOC_EXT_BITS_TYPE_SH_LITTLE); 215 216 PUT_WORD (abfd, r_addend, natptr->r_addend); 217} 218 219/* We need our own to assert that a normal 8, 16 or 32 reloc is input. */ 220 221static void 222MY (swap_ext_reloc_in) (bfd *abfd, 223 struct reloc_ext_external *bytes, 224 arelent *cache_ptr, 225 asymbol **symbols, 226 bfd_size_type symcount) 227{ 228 unsigned int r_index; 229 int r_extern; 230 unsigned int r_type; 231 struct aoutdata *su = &(abfd->tdata.aout_data->a); 232 233 cache_ptr->address = (GET_SWORD (abfd, bytes->r_address)); 234 235 /* Now the fun stuff. */ 236 r_index = (bytes->r_index[2] << 16) 237 | (bytes->r_index[1] << 8) 238 | bytes->r_index[0]; 239 r_extern = (0 != (bytes->r_type[0] & RELOC_EXT_BITS_EXTERN_LITTLE)); 240 r_type = ((bytes->r_type[0]) >> RELOC_EXT_BITS_TYPE_SH_LITTLE) 241 & RELOC_EXT_BITS_TYPE_LITTLE; 242 243 if (r_type > 2) 244 { 245 (*_bfd_error_handler) (_("%B: Invalid relocation type imported: %d"), 246 abfd, r_type); 247 248 bfd_set_error (bfd_error_wrong_format); 249 } 250 251 cache_ptr->howto = howto_table_ext + r_type; 252 253 if (r_extern && r_index > symcount) 254 { 255 (*_bfd_error_handler) 256 (_("%B: Bad relocation record imported: %d"), abfd, r_index); 257 258 bfd_set_error (bfd_error_wrong_format); 259 260 /* We continue, so we can catch further errors. */ 261 r_extern = 0; 262 r_index = N_ABS; 263 } 264 265 /* Magically uses r_extern, symbols etc. Ugly, but it's what's in the 266 default. */ 267 MOVE_ADDRESS (GET_SWORD (abfd, bytes->r_addend)); 268} 269 270/* We use the same as the default, except that we also set 271 "obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE;", to avoid changing 272 NAME (aout, set_arch_mach) in aoutx. */ 273 274static bfd_boolean 275MY (set_sizes) (bfd *abfd) 276{ 277 /* Just as the default in aout-target.h (with some #ifdefs folded)... */ 278 279 adata (abfd).page_size = TARGET_PAGE_SIZE; 280 adata (abfd).segment_size = SEGMENT_SIZE; 281 adata (abfd).zmagic_disk_block_size = ZMAGIC_DISK_BLOCK_SIZE; 282 adata (abfd).exec_bytes_size = EXEC_BYTES_SIZE; 283 284 /* ... except for that we have the extended reloc. The alternative 285 would be to add a check on bfd_arch_cris in NAME (aout, 286 set_arch_mach) in aoutx.h, but I don't want to do that since 287 target-specific things should not be added there. */ 288 289 obj_reloc_entry_size (abfd) = RELOC_EXT_SIZE; 290 291 return TRUE; 292} 293