bfd/elf32-s12z.c

   1 /* Freescale S12Z-specific support for 32-bit ELF
   2    Copyright (C) 1999-2021 Free Software Foundation, Inc.
   3    (Heavily copied from the D10V port by Martin Hunt (hunt@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 "bfdlink.h"
  25 #include "libbfd.h"
  26 #include "elf-bfd.h"
  27
  28 #include "elf/s12z.h"
  29
  30 /* All users of this file have bfd_octets_per_byte (abfd, sec) == 1.  */
  31 #define OCTETS_PER_BYTE(ABFD, SEC) 1
  32
  33 /* Relocation functions.  */
  34 static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
  35   (bfd *, bfd_reloc_code_real_type);
  36 static bool s12z_info_to_howto_rel
  37   (bfd *, arelent *, Elf_Internal_Rela *);
  38
  39 static bfd_reloc_status_type
  40 opru18_reloc (bfd *abfd, arelent *reloc_entry, struct bfd_symbol *symbol,
  41                     void *data, asection *input_section ATTRIBUTE_UNUSED,
  42                     bfd *output ATTRIBUTE_UNUSED, char **msg ATTRIBUTE_UNUSED)
  43 {
  44   /* This reloc is used for 18 bit General Operand Addressing Postbyte in the
  45      INST opru18 form.  This is an 18 bit reloc, but the most significant bit
  46      is shifted one place to the left of where it would normally be.  See
  47      Appendix A.4 of the S12Z reference manual.  */
  48
  49   bfd_size_type octets = (reloc_entry->address
  50                           * OCTETS_PER_BYTE (abfd, input_section));
  51   bfd_vma result = bfd_get_24 (abfd, (unsigned char *) data + octets);
  52   bfd_vma val = bfd_asymbol_value (symbol);
  53
  54   /* Keep the wanted bits and discard the rest.  */
  55   result &= 0xFA0000;
  56
  57   val += symbol->section->output_section->vma;
  58   val += symbol->section->output_offset;
  59
  60   /* The lowest 17 bits are copied verbatim.  */
  61   result |= val & 0x1FFFF;
  62
  63   /* The 18th bit is put into the 19th position.  */
  64   result |= (val & 0x020000) << 1;
  65
  66   bfd_put_24 (abfd, result, (unsigned char *) data + octets);
  67
  68   return bfd_reloc_ok;
  69 }
  70
  71
  72 static bfd_reloc_status_type
  73 shift_addend_reloc (bfd *abfd, arelent *reloc_entry, struct bfd_symbol *symbol ATTRIBUTE_UNUSED,
  74                     void *data ATTRIBUTE_UNUSED, asection *input_section ATTRIBUTE_UNUSED,
  75                     bfd *output ATTRIBUTE_UNUSED, char **msg ATTRIBUTE_UNUSED)
  76 {
  77   /* This is a really peculiar reloc, which is done for compatibility
  78      with the Freescale toolchain.
  79
  80      That toolchain appears to (ab)use the lowest 15 bits of the addend for
  81      the purpose of holding flags.  The purpose of these flags are unknown.
  82      So in this function, when writing the bfd we left shift the addend by
  83      15, and when reading we right shift it by 15 (discarding the lower bits).
  84
  85      This allows the linker to work with object files generated by Freescale,
  86      as well as by Gas.  */
  87
  88   if (abfd->is_linker_input)
  89     reloc_entry->addend >>= 15;
  90   else
  91     reloc_entry->addend <<= 15;
  92
  93   return bfd_reloc_continue;
  94 }
  95
  96 #define USE_REL 0
  97
  98 static reloc_howto_type elf_s12z_howto_table[] =
  99 {
 100   /* This reloc does nothing.  */
 101   HOWTO (R_S12Z_NONE,   /* type */
 102          0,                     /* rightshift */
 103          3,                     /* size (0 = byte, 1 = short, 2 = long) */
 104          0,                     /* bitsize */
 105          false,                 /* pc_relative */
 106          0,                     /* bitpos */
 107          complain_overflow_dont,/* complain_on_overflow */
 108          bfd_elf_generic_reloc, /* special_function */
 109          "R_S12Z_NONE", /* name */
 110          false,                 /* partial_inplace */
 111          0,                     /* src_mask */
 112          0,                     /* dst_mask */
 113          false),                /* pcrel_offset */
 114
 115   /* A 24 bit absolute relocation emitted by the OPR mode operands  */
 116   HOWTO (R_S12Z_OPR,        /* type */
 117          0,                     /* rightshift */
 118          5,                     /* size (0 = byte, 1 = short, 2 = long) */
 119          24,                    /* bitsize */
 120          false,                 /* pc_relative */
 121          0,                     /* bitpos */
 122          complain_overflow_bitfield,    /* complain_on_overflow */
 123          shift_addend_reloc,
 124          "R_S12Z_OPR",  /* name */
 125          false,                 /* partial_inplace */
 126          0x00ffffff,            /* src_mask */
 127          0x00ffffff,            /* dst_mask */
 128          false),                /* pcrel_offset */
 129
 130   /* The purpose of this reloc is not known */
 131   HOWTO (R_S12Z_UKNWN_2,        /* type */
 132          0,                     /* rightshift */
 133          3,                     /* size (0 = byte, 1 = short, 2 = long) */
 134          0,                     /* bitsize */
 135          false,                 /* pc_relative */
 136          0,                     /* bitpos */
 137          complain_overflow_dont,/* complain_on_overflow */
 138          bfd_elf_generic_reloc, /* special_function */
 139          "R_S12Z_UKNWN_2",      /* name */
 140          false,                 /* partial_inplace */
 141          0,                     /* src_mask */
 142          0,                     /* dst_mask */
 143          false),                /* pcrel_offset */
 144
 145   /* A 15 bit PC-rel relocation */
 146   HOWTO (R_S12Z_PCREL_7_15,     /* type */
 147          0,                     /* rightshift */
 148          1,                     /* size (0 = byte, 1 = short, 2 = long) */
 149          15,                    /* bitsize */
 150          true,                  /* pc_relative */
 151          0,                     /* bitpos */
 152          complain_overflow_bitfield,    /* complain_on_overflow */
 153          shift_addend_reloc,
 154          "R_S12Z_PCREL_7_15",   /* name */
 155          false,                 /* partial_inplace */
 156          0x00,                  /* src_mask */
 157          0x007fff,              /* dst_mask */
 158          true),                 /* pcrel_offset */
 159
 160   /* A 24 bit absolute relocation emitted by EXT24 mode operands */
 161   HOWTO (R_S12Z_EXT24,        /* type */
 162          0,                     /* rightshift */
 163          5,                     /* size (0 = byte, 1 = short, 2 = long) */
 164          24,                    /* bitsize */
 165          false,                 /* pc_relative */
 166          0,                     /* bitpos */
 167          complain_overflow_bitfield,    /* complain_on_overflow */
 168          bfd_elf_generic_reloc, /* special_function */
 169          "R_S12Z_EXT24",        /* name */
 170          false,                 /* partial_inplace */
 171          0x00000000,            /* src_mask */
 172          0x00ffffff,            /* dst_mask */
 173          false),                /* pcrel_offset */
 174
 175   /* An 18 bit absolute relocation */
 176   HOWTO (R_S12Z_EXT18,        /* type */
 177          0,                     /* rightshift */
 178          5,                     /* size (0 = byte, 1 = short, 2 = long) */
 179          18,                    /* bitsize */
 180          false,                 /* pc_relative */
 181          0,                     /* bitpos */
 182          complain_overflow_bitfield,    /* complain_on_overflow */
 183          opru18_reloc,          /* special_function */
 184          "R_S12Z_EXT18",        /* name */
 185          false,                 /* partial_inplace */
 186          0x00000000,            /* src_mask */
 187          0x0005ffff,            /* dst_mask */
 188          false),                /* pcrel_offset */
 189
 190   /* A 32 bit absolute relocation.   This kind of relocation is
 191      schizophrenic - Although they appear in sections named .rela.debug.*
 192      in some sections they behave as RELA relocs, but in others they have
 193      an added of zero and behave as REL.
 194
 195      It is not recommended that new code  emits this reloc.   It is here
 196      only to support existing elf files generated by third party
 197      applications.  */
 198
 199   HOWTO (R_S12Z_CW32,        /* type */
 200          0,                     /* rightshift */
 201          2,                     /* size (0 = byte, 1 = short, 2 = long) */
 202          32,                    /* bitsize */
 203          false,                 /* pc_relative */
 204          0,                     /* bitpos */
 205          complain_overflow_bitfield,    /* complain_on_overflow */
 206          bfd_elf_generic_reloc, /* special_function */
 207          "R_S12Z_CW32", /* name */
 208          false,                 /* partial_inplace */
 209          0xffffffff,            /* src_mask */
 210          0xffffffff,            /* dst_mask */
 211          false),                /* pcrel_offset */
 212
 213   /* A 32 bit absolute relocation  */
 214   HOWTO (R_S12Z_EXT32,        /* type */
 215          0,                     /* rightshift */
 216          2,                     /* size (0 = byte, 1 = short, 2 = long) */
 217          32,                    /* bitsize */
 218          false,                 /* pc_relative */
 219          0,                     /* bitpos */
 220          complain_overflow_bitfield,    /* complain_on_overflow */
 221          bfd_elf_generic_reloc, /* special_function */
 222          "R_S12Z_EXT32",        /* name */
 223          false,                 /* partial_inplace */
 224          0x00000000,            /* src_mask */
 225          0xffffffff,            /* dst_mask */
 226          false),                /* pcrel_offset */
 227 };
 228
 229 /* Map BFD reloc types to S12Z ELF reloc types.  */
 230
 231 struct s12z_reloc_map
 232 {
 233   bfd_reloc_code_real_type bfd_reloc_val;
 234   unsigned char elf_reloc_val;
 235 };
 236
 237 static const struct s12z_reloc_map s12z_reloc_map[] =
 238 {
 239   /* bfd reloc val */  /* elf reloc val */
 240   {BFD_RELOC_NONE,     R_S12Z_NONE},
 241   {BFD_RELOC_32,       R_S12Z_EXT32},
 242   {BFD_RELOC_24,       R_S12Z_EXT24},
 243   {BFD_RELOC_16_PCREL, R_S12Z_PCREL_7_15},
 244   {BFD_RELOC_S12Z_OPR, R_S12Z_OPR}
 245 };
 246
 247 static reloc_howto_type *
 248 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
 249                                  bfd_reloc_code_real_type code)
 250 {
 251   unsigned int i;
 252
 253   for (i = 0;
 254        i < sizeof (s12z_reloc_map) / sizeof (struct s12z_reloc_map);
 255        i++)
 256     {
 257       if (s12z_reloc_map[i].bfd_reloc_val == code)
 258         {
 259           return &elf_s12z_howto_table[s12z_reloc_map[i].elf_reloc_val];
 260         }
 261     }
 262
 263   printf ("%s:%d Not found type %d\n", __FILE__, __LINE__, code);
 264
 265   return NULL;
 266 }
 267
 268 static reloc_howto_type *
 269 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
 270                                  const char *r_name)
 271 {
 272   unsigned int i;
 273
 274   for (i = 0;
 275        i < (sizeof (elf_s12z_howto_table)
 276             / sizeof (elf_s12z_howto_table[0]));
 277        i++)
 278     if (elf_s12z_howto_table[i].name != NULL
 279         && strcasecmp (elf_s12z_howto_table[i].name, r_name) == 0)
 280       return &elf_s12z_howto_table[i];
 281
 282   return NULL;
 283 }
 284
 285 /* Set the howto pointer for an S12Z ELF reloc.  */
 286
 287 static bool
 288 s12z_info_to_howto_rel (bfd *abfd,
 289                           arelent *cache_ptr, Elf_Internal_Rela *dst)
 290 {
 291   unsigned int  r_type = ELF32_R_TYPE (dst->r_info);
 292
 293   if (r_type >= (unsigned int) R_S12Z_max)
 294     {
 295       /* xgettext:c-format */
 296       _bfd_error_handler (_("%pB: unsupported relocation type %#x"),
 297                           abfd, r_type);
 298       bfd_set_error (bfd_error_bad_value);
 299       return false;
 300     }
 301
 302   cache_ptr->howto = &elf_s12z_howto_table[r_type];
 303   return true;
 304 }
 305
 306 static bool
 307 s12z_elf_set_mach_from_flags (bfd *abfd)
 308 {
 309   bfd_default_set_arch_mach (abfd, bfd_arch_s12z, 0);
 310
 311   return true;
 312 }
 313
 314 #define ELF_ARCH                bfd_arch_s12z
 315 #define ELF_MACHINE_CODE        EM_S12Z
 316 #define ELF_MAXPAGESIZE         0x1000
 317
 318 #define TARGET_BIG_SYM          s12z_elf32_vec
 319 #define TARGET_BIG_NAME         "elf32-s12z"
 320
 321 #define elf_info_to_howto                       NULL
 322 #define elf_info_to_howto_rel                   s12z_info_to_howto_rel
 323 #define elf_backend_object_p                    s12z_elf_set_mach_from_flags
 324
 325 #include "elf32-target.h"