bfd/aout-ns32k.c

   1 /* BFD back-end for ns32k a.out-ish binaries.
   2    Copyright (C) 1990-2024 Free Software Foundation, Inc.
   3    Contributed by Ian Dall (idall@eleceng.adelaide.edu.au).
   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 "aout/aout64.h"
  26 #include "ns32k.h"
  27
  28 /* Do not "beautify" the CONCAT* macro args.  Traditional C will not
  29    remove whitespace added here, and thus will fail to concatenate
  30    the tokens.  */
  31 #define MYNS(OP) CONCAT2 (ns32k_aout_,OP)
  32
  33 reloc_howto_type * MYNS (bfd_reloc_type_lookup) (bfd *, bfd_reloc_code_real_type);
  34 reloc_howto_type * MYNS (bfd_reloc_name_lookup) (bfd *, const char *);
  35 bool MYNS (write_object_contents) (bfd *);
  36
  37 /* Avoid multiple definitions from aoutx if supporting
  38    standard a.out format(s) as well as this one.  */
  39 #define NAME(x,y) CONCAT3 (ns32kaout,_32_,y)
  40
  41 void bfd_ns32k_arch (void);
  42
  43 #include "libaout.h"
  44
  45 #define MY(OP) MYNS (OP)
  46
  47 #define MY_swap_std_reloc_in   MY (swap_std_reloc_in)
  48 #define MY_swap_std_reloc_out  MY (swap_std_reloc_out)
  49
  50 /* The ns32k series is ah, unusual, when it comes to relocation.
  51    There are three storage methods for relocatable objects.  There
  52    are displacements, immediate operands and ordinary twos complement
  53    data. Of these, only the last fits into the standard relocation
  54    scheme.  Immediate operands are stored huffman encoded and
  55    immediate operands are stored big endian (where as the natural byte
  56    order is little endian for this architecture).
  57
  58    Note that the ns32k displacement storage method is orthogonal to
  59    whether the relocation is pc relative or not. The "displacement"
  60    storage scheme is used for essentially all address constants. The
  61    displacement can be relative to zero (absolute displacement),
  62    relative to the pc (pc relative), the stack pointer, the frame
  63    pointer, the static base register and general purpose register etc.
  64
  65    For example:
  66
  67    sym1: .long .         # pc relative 2's complement
  68    sym1: .long foo       # 2's complement not pc relative
  69
  70    self:  movd @self, r0 # pc relative displacement
  71           movd foo, r0   # non pc relative displacement
  72
  73    self:  movd self, r0  # pc relative immediate
  74           movd foo, r0   # non pc relative immediate
  75
  76    In addition, for historical reasons the encoding of the relocation types
  77    in the a.out format relocation entries is such that even the relocation
  78    methods which are standard are not encoded the standard way.  */
  79
  80 reloc_howto_type MY (howto_table)[] =
  81 {
  82   /* ns32k immediate operands.  */
  83   HOWTO (BFD_RELOC_NS32K_IMM_8, 0, 1, 8, false, 0, complain_overflow_signed,
  84          _bfd_ns32k_reloc_imm, "NS32K_IMM_8",
  85          true, 0x000000ff,0x000000ff, false),
  86   HOWTO (BFD_RELOC_NS32K_IMM_16, 0, 2, 16, false, 0, complain_overflow_signed,
  87          _bfd_ns32k_reloc_imm,  "NS32K_IMM_16",
  88          true, 0x0000ffff,0x0000ffff, false),
  89   HOWTO (BFD_RELOC_NS32K_IMM_32, 0, 4, 32, false, 0, complain_overflow_signed,
  90          _bfd_ns32k_reloc_imm, "NS32K_IMM_32",
  91          true, 0xffffffff,0xffffffff, false),
  92   HOWTO (BFD_RELOC_NS32K_IMM_8_PCREL, 0, 1, 8, true, 0, complain_overflow_signed,
  93          _bfd_ns32k_reloc_imm, "PCREL_NS32K_IMM_8",
  94          true, 0x000000ff, 0x000000ff, false),
  95   HOWTO (BFD_RELOC_NS32K_IMM_16_PCREL, 0, 2, 16, true, 0, complain_overflow_signed,
  96          _bfd_ns32k_reloc_imm, "PCREL_NS32K_IMM_16",
  97          true, 0x0000ffff,0x0000ffff, false),
  98   HOWTO (BFD_RELOC_NS32K_IMM_32_PCREL, 0, 4, 32, true, 0, complain_overflow_signed,
  99          _bfd_ns32k_reloc_imm, "PCREL_NS32K_IMM_32",
 100          true, 0xffffffff,0xffffffff, false),
 101
 102   /* ns32k displacements.  */
 103   HOWTO (BFD_RELOC_NS32K_DISP_8, 0, 1, 7, false, 0, complain_overflow_signed,
 104          _bfd_ns32k_reloc_disp, "NS32K_DISP_8",
 105          true, 0x000000ff,0x000000ff, false),
 106   HOWTO (BFD_RELOC_NS32K_DISP_16, 0, 2, 14, false, 0, complain_overflow_signed,
 107          _bfd_ns32k_reloc_disp, "NS32K_DISP_16",
 108          true, 0x0000ffff, 0x0000ffff, false),
 109   HOWTO (BFD_RELOC_NS32K_DISP_32, 0, 4, 30, false, 0, complain_overflow_signed,
 110          _bfd_ns32k_reloc_disp, "NS32K_DISP_32",
 111          true, 0xffffffff, 0xffffffff, false),
 112   HOWTO (BFD_RELOC_NS32K_DISP_8_PCREL, 0, 1, 7, true, 0, complain_overflow_signed,
 113            _bfd_ns32k_reloc_disp, "PCREL_NS32K_DISP_8",
 114          true, 0x000000ff,0x000000ff, false),
 115   HOWTO (BFD_RELOC_NS32K_DISP_16_PCREL, 0, 2, 14, true, 0, complain_overflow_signed,
 116          _bfd_ns32k_reloc_disp, "PCREL_NS32K_DISP_16",
 117          true, 0x0000ffff,0x0000ffff, false),
 118   HOWTO (BFD_RELOC_NS32K_DISP_32_PCREL, 0, 4, 30, true, 0, complain_overflow_signed,
 119          _bfd_ns32k_reloc_disp, "PCREL_NS32K_DISP_32",
 120          true, 0xffffffff,0xffffffff, false),
 121
 122   /* Normal 2's complement.  */
 123   HOWTO (BFD_RELOC_8, 0, 1, 8, false, 0, complain_overflow_bitfield,0,
 124          "8", true, 0x000000ff,0x000000ff, false),
 125   HOWTO (BFD_RELOC_16, 0, 2, 16, false, 0, complain_overflow_bitfield,0,
 126          "16", true, 0x0000ffff,0x0000ffff, false),
 127   HOWTO (BFD_RELOC_32, 0, 4, 32, false, 0, complain_overflow_bitfield,0,
 128          "32", true, 0xffffffff,0xffffffff, false),
 129   HOWTO (BFD_RELOC_8_PCREL, 0, 1, 8, true, 0, complain_overflow_signed, 0,
 130          "PCREL_8", true, 0x000000ff,0x000000ff, false),
 131   HOWTO (BFD_RELOC_16_PCREL, 0, 2, 16, true, 0, complain_overflow_signed, 0,
 132          "PCREL_16", true, 0x0000ffff,0x0000ffff, false),
 133   HOWTO (BFD_RELOC_32_PCREL, 0, 4, 32, true, 0, complain_overflow_signed, 0,
 134          "PCREL_32", true, 0xffffffff,0xffffffff, false),
 135 };
 136
 137 #define CTOR_TABLE_RELOC_HOWTO(BFD) (MY (howto_table) + 14)
 138
 139 #define RELOC_STD_BITS_NS32K_TYPE_BIG           0x06
 140 #define RELOC_STD_BITS_NS32K_TYPE_LITTLE        0x60
 141 #define RELOC_STD_BITS_NS32K_TYPE_SH_BIG        1
 142 #define RELOC_STD_BITS_NS32K_TYPE_SH_LITTLE     5
 143
 144 static reloc_howto_type *
 145 MY (reloc_howto) (bfd *abfd ATTRIBUTE_UNUSED,
 146                   struct reloc_std_external *rel,
 147                   unsigned int *r_index,
 148                   int *r_extern,
 149                   int *r_pcrel)
 150 {
 151   unsigned int r_length;
 152   unsigned int r_ns32k_type;
 153
 154   *r_index =  ((rel->r_index[2] << 16)
 155                | (rel->r_index[1] << 8)
 156                |  rel->r_index[0] );
 157   *r_extern  = (0 != (rel->r_type[0] & RELOC_STD_BITS_EXTERN_LITTLE));
 158   *r_pcrel   = (0 != (rel->r_type[0] & RELOC_STD_BITS_PCREL_LITTLE));
 159   r_length  =  ((rel->r_type[0] & RELOC_STD_BITS_LENGTH_LITTLE)
 160                 >> RELOC_STD_BITS_LENGTH_SH_LITTLE);
 161   r_ns32k_type  =  ((rel->r_type[0] & RELOC_STD_BITS_NS32K_TYPE_LITTLE)
 162                     >> RELOC_STD_BITS_NS32K_TYPE_SH_LITTLE);
 163   if (r_length > 2 || r_ns32k_type > 2)
 164     return NULL;
 165   return (MY (howto_table) + r_length + 3 * (*r_pcrel) + 6 * r_ns32k_type);
 166 }
 167
 168 #define MY_reloc_howto(BFD, REL, IN, EX, PC) \
 169   MY (reloc_howto) (BFD, REL, &IN, &EX, &PC)
 170
 171 static void
 172 MY (put_reloc) (bfd *abfd,
 173                 int r_extern,
 174                 int r_index,
 175                 bfd_vma value,
 176                 reloc_howto_type *howto,
 177                 struct reloc_std_external *reloc)
 178 {
 179   unsigned int r_length;
 180   int r_pcrel;
 181   int r_ns32k_type;
 182
 183   PUT_WORD (abfd, value, reloc->r_address);
 184   r_length = bfd_log2 (bfd_get_reloc_size (howto));
 185   r_pcrel  = (int) howto->pc_relative; /* Relative to PC?  */
 186   r_ns32k_type = (howto - MY (howto_table) )/6;
 187
 188   reloc->r_index[2] = r_index >> 16;
 189   reloc->r_index[1] = r_index >> 8;
 190   reloc->r_index[0] = r_index;
 191   reloc->r_type[0] =
 192     (r_extern?    RELOC_STD_BITS_EXTERN_LITTLE: 0)
 193       | (r_pcrel?     RELOC_STD_BITS_PCREL_LITTLE: 0)
 194         | (r_length <<  RELOC_STD_BITS_LENGTH_SH_LITTLE)
 195           | (r_ns32k_type <<  RELOC_STD_BITS_NS32K_TYPE_SH_LITTLE);
 196 }
 197
 198 #define MY_put_reloc(BFD, EXT, IDX, VAL, HOWTO, RELOC) \
 199   MY (put_reloc) (BFD, EXT, IDX, VAL, HOWTO, RELOC)
 200
 201 #define STAT_FOR_EXEC
 202
 203 #define MY_final_link_relocate _bfd_ns32k_final_link_relocate
 204 #define MY_relocate_contents   _bfd_ns32k_relocate_contents
 205
 206 static void MY_swap_std_reloc_in (bfd *, struct reloc_std_external *, arelent *, asymbol **, bfd_size_type);
 207 static void MY_swap_std_reloc_out (bfd *, arelent *, struct reloc_std_external *);
 208
 209 #include "aoutx.h"
 210
 211 reloc_howto_type *
 212 MY (bfd_reloc_type_lookup) (bfd *abfd, bfd_reloc_code_real_type code)
 213 {
 214 #define ENTRY(i,j)      case i: return &MY (howto_table)[j]
 215
 216   int ext = obj_reloc_entry_size (abfd) == RELOC_EXT_SIZE;
 217
 218   BFD_ASSERT (ext == 0);
 219   if (code == BFD_RELOC_CTOR)
 220     switch (bfd_arch_bits_per_address (abfd))
 221       {
 222       case 32:
 223         code = BFD_RELOC_32;
 224         break;
 225       default:
 226         break;
 227       }
 228   switch (code)
 229     {
 230       ENTRY (BFD_RELOC_NS32K_IMM_8, 0);
 231       ENTRY (BFD_RELOC_NS32K_IMM_16, 1);
 232       ENTRY (BFD_RELOC_NS32K_IMM_32, 2);
 233       ENTRY (BFD_RELOC_NS32K_IMM_8_PCREL, 3);
 234       ENTRY (BFD_RELOC_NS32K_IMM_16_PCREL, 4);
 235       ENTRY (BFD_RELOC_NS32K_IMM_32_PCREL, 5);
 236       ENTRY (BFD_RELOC_NS32K_DISP_8, 6);
 237       ENTRY (BFD_RELOC_NS32K_DISP_16, 7);
 238       ENTRY (BFD_RELOC_NS32K_DISP_32, 8);
 239       ENTRY (BFD_RELOC_NS32K_DISP_8_PCREL, 9);
 240       ENTRY (BFD_RELOC_NS32K_DISP_16_PCREL, 10);
 241       ENTRY (BFD_RELOC_NS32K_DISP_32_PCREL, 11);
 242       ENTRY (BFD_RELOC_8, 12);
 243       ENTRY (BFD_RELOC_16, 13);
 244       ENTRY (BFD_RELOC_32, 14);
 245       ENTRY (BFD_RELOC_8_PCREL, 15);
 246       ENTRY (BFD_RELOC_16_PCREL, 16);
 247       ENTRY (BFD_RELOC_32_PCREL, 17);
 248     default:
 249       return NULL;
 250     }
 251 #undef ENTRY
 252 }
 253
 254 reloc_howto_type *
 255 MY (bfd_reloc_name_lookup) (bfd *abfd ATTRIBUTE_UNUSED,
 256                             const char *r_name)
 257 {
 258   unsigned int i;
 259
 260   for (i = 0;
 261        i < sizeof (MY (howto_table)) / sizeof (MY (howto_table)[0]);
 262        i++)
 263     if (MY (howto_table)[i].name != NULL
 264         && strcasecmp (MY (howto_table)[i].name, r_name) == 0)
 265       return &MY (howto_table)[i];
 266
 267   return NULL;
 268 }
 269
 270 static void
 271 MY_swap_std_reloc_in (bfd *abfd,
 272                       struct reloc_std_external *bytes,
 273                       arelent *cache_ptr,
 274                       asymbol **symbols,
 275                       bfd_size_type symcount ATTRIBUTE_UNUSED)
 276 {
 277   unsigned int r_index;
 278   int r_extern;
 279   int r_pcrel;
 280   struct aoutdata  *su = &(abfd->tdata.aout_data->a);
 281
 282   cache_ptr->address = H_GET_32 (abfd, bytes->r_address);
 283
 284   /* Now the fun stuff.  */
 285   cache_ptr->howto = MY_reloc_howto (abfd, bytes, r_index, r_extern, r_pcrel);
 286
 287   MOVE_ADDRESS (0);
 288 }
 289
 290 static void
 291 MY_swap_std_reloc_out (bfd *abfd,
 292                        arelent *g,
 293                        struct reloc_std_external *natptr)
 294 {
 295   int r_index;
 296   asymbol *sym = *(g->sym_ptr_ptr);
 297   int r_extern;
 298   asection *output_section = sym->section->output_section;
 299
 300   /* Name was clobbered by aout_write_syms to be symbol index.  */
 301
 302   /* If this relocation is relative to a symbol then set the
 303      r_index to the symbols index, and the r_extern bit.
 304
 305      Absolute symbols can come in in two ways, either as an offset
 306      from the abs section, or as a symbol which has an abs value.
 307      Check for that here.  */
 308   if (bfd_is_com_section (output_section)
 309       || bfd_is_abs_section (output_section)
 310       || bfd_is_und_section (output_section))
 311     {
 312       if (bfd_abs_section_ptr->symbol == sym)
 313         {
 314           /* Whoops, looked like an abs symbol, but is really an offset
 315              from the abs section.  */
 316           r_index = 0;
 317           r_extern = 0;
 318         }
 319       else
 320         {
 321           /* Fill in symbol.  */
 322           r_extern = 1;
 323 #undef KEEPIT
 324 #define KEEPIT udata.i
 325           r_index =  (*(g->sym_ptr_ptr))->KEEPIT;
 326 #undef KEEPIT
 327         }
 328     }
 329   else
 330     {
 331       /* Just an ordinary section.  */
 332       r_extern = 0;
 333       r_index  = output_section->target_index;
 334     }
 335
 336   MY_put_reloc (abfd, r_extern, r_index, g->address, g->howto, natptr);
 337 }
 338
 339 bfd_reloc_status_type
 340 _bfd_ns32k_relocate_contents (reloc_howto_type *howto,
 341                               bfd *input_bfd,
 342                               bfd_vma relocation,
 343                               bfd_byte *location)
 344 {
 345   int r_ns32k_type = (howto - MY (howto_table)) / 6;
 346   bfd_vma (*get_data) (bfd_byte *, int);
 347   void (*put_data) (bfd_vma, bfd_byte *, int);
 348
 349   switch (r_ns32k_type)
 350     {
 351     case 0:
 352       get_data = _bfd_ns32k_get_immediate;
 353       put_data = _bfd_ns32k_put_immediate;
 354       break;
 355     case 1:
 356       get_data = _bfd_ns32k_get_displacement;
 357       put_data = _bfd_ns32k_put_displacement;
 358       break;
 359     case 2:
 360       return _bfd_relocate_contents (howto, input_bfd, relocation,
 361                                     location);
 362     default:
 363       return bfd_reloc_notsupported;
 364     }
 365   return _bfd_do_ns32k_reloc_contents (howto, input_bfd, relocation,
 366                                        location, get_data, put_data);
 367 }