/* Morpho Technologies MT specific support for 32-bit ELF

   Copyright (C) 2001-2025 Free Software Foundation, Inc.

   This file is part of BFD, the Binary File Descriptor library.

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program; if not, write to the Free Software

   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,

   MA 02110-1301, USA.  */

#include "sysdep.h"

#include "bfd.h"

#include "libbfd.h"

#include "elf-bfd.h"

#include "elf/mt.h"

/* Prototypes.  */

static reloc_howto_type * mt_reloc_type_lookup

  (bfd *, bfd_reloc_code_real_type);

static bool mt_info_to_howto_rela

  (bfd *, arelent *, Elf_Internal_Rela *);

static bfd_reloc_status_type mt_elf_relocate_hi16

  (bfd *, Elf_Internal_Rela *, bfd_byte *, bfd_vma);

static bfd_reloc_status_type mt_final_link_relocate

  (reloc_howto_type *, bfd *, asection *, bfd_byte *,

   Elf_Internal_Rela *, bfd_vma);

static int mt_elf_relocate_section

  (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,

   Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);

/* Relocation tables.  */

static reloc_howto_type mt_elf_howto_table [] =

{

  /* This reloc does nothing.  */

  HOWTO (R_MT_NONE,       /* type */

    0,        /* rightshift */

    0,        /* size */

    0,        /* bitsize */

    false,      /* pc_relative */

    0,        /* bitpos */

    complain_overflow_dont, /* complain_on_overflow */

    bfd_elf_generic_reloc,  /* special_function */

    "R_MT_NONE",    /* name */

    false,      /* partial_inplace */

    0 ,       /* src_mask */

    0,        /* dst_mask */

    false),     /* pcrel_offset */

  /* A 16 bit absolute relocation.  */

  HOWTO (R_MT_16,       /* type */

    0,        /* rightshift */

    4,        /* size */

    16,       /* bitsize */

    false,      /* pc_relative */

    0,        /* bitpos */

    complain_overflow_dont, /* complain_on_overflow */

    bfd_elf_generic_reloc,  /* special_function */

    "R_MT_16",    /* name */

    false,      /* partial_inplace */

    0 ,       /* src_mask */

    0xffff,     /* dst_mask */

    false),     /* pcrel_offset */

  /* A 32 bit absolute relocation.  */

  HOWTO (R_MT_32,       /* type */

    0,        /* rightshift */

    4,        /* size */

    32,       /* bitsize */

    false,      /* pc_relative */

    0,        /* bitpos */

    complain_overflow_dont, /* complain_on_overflow */

    bfd_elf_generic_reloc,  /* special_function */

    "R_MT_32",    /* name */

    false,      /* partial_inplace */

    0 ,       /* src_mask */

    0xffffffff,     /* dst_mask */

    false),     /* pcrel_offset */

  /* A 32 bit pc-relative relocation.  */

  HOWTO (R_MT_32_PCREL,       /* type */

    0,        /* rightshift */

    4,        /* size */

    32,       /* bitsize */

    true,       /* pc_relative */

    0,        /* bitpos */

    complain_overflow_dont, /* complain_on_overflow */

    bfd_elf_generic_reloc,  /* special_function */

    "R_MT_32_PCREL",    /* name */

    false,      /* partial_inplace */

    0 ,       /* src_mask */

    0xffffffff,     /* dst_mask */

    true),      /* pcrel_offset */

  /* A 16 bit pc-relative relocation.  */

  HOWTO (R_MT_PC16,       /* type */

    0,        /* rightshift */

    4,        /* size */

    16,       /* bitsize */

    true,       /* pc_relative */

    0,        /* bitpos */

    complain_overflow_signed, /* complain_on_overflow */

    bfd_elf_generic_reloc,  /* special_function */

    "R_MT_PC16",    /* name */

    false,      /* partial_inplace */

    0,        /* src_mask */

    0xffff,     /* dst_mask */

    true),      /* pcrel_offset */

  /* high 16 bits of symbol value.  */

  HOWTO (R_MT_HI16,      /* type */

   0,     /* rightshift */

   4,     /* size */

   16,      /* bitsize */

   false,     /* pc_relative */

   0,     /* bitpos */

   complain_overflow_dont, /* complain_on_overflow */

   bfd_elf_generic_reloc, /* special_function */

   "R_MT_HI16",      /* name */

   false,      /* partial_inplace */

   0xffff0000,    /* src_mask */

   0xffff0000,    /* dst_mask */

   false),    /* pcrel_offset */

  /* Low 16 bits of symbol value.  */

  HOWTO (R_MT_LO16,      /* type */

   0,     /* rightshift */

   4,     /* size */

   16,      /* bitsize */

   false,     /* pc_relative */

   0,     /* bitpos */

   complain_overflow_dont, /* complain_on_overflow */

   bfd_elf_generic_reloc, /* special_function */

   "R_MT_LO16",      /* name */

   false,      /* partial_inplace */

   0xffff,    /* src_mask */

   0xffff,    /* dst_mask */

   false),    /* pcrel_offset */

};

/* Map BFD reloc types to MT ELF reloc types.  */

static reloc_howto_type *

mt_reloc_type_lookup

    (bfd *          abfd ATTRIBUTE_UNUSED,

     bfd_reloc_code_real_type code)

{

  /* Note that the mt_elf_howto_table is indxed by the R_

     constants.  Thus, the order that the howto records appear in the

     table *must* match the order of the relocation types defined in

     include/elf/mt.h.  */

  switch (code)

    {

    case BFD_RELOC_NONE:

      return &mt_elf_howto_table[ (int) R_MT_NONE];

    case BFD_RELOC_16:

      return &mt_elf_howto_table[ (int) R_MT_16];

    case BFD_RELOC_32:

      return &mt_elf_howto_table[ (int) R_MT_32];

    case BFD_RELOC_32_PCREL:

      return &mt_elf_howto_table[ (int) R_MT_32_PCREL];

    case BFD_RELOC_16_PCREL:

      return &mt_elf_howto_table[ (int) R_MT_PC16];

    case BFD_RELOC_HI16:

      return &mt_elf_howto_table[ (int) R_MT_HI16];

    case BFD_RELOC_LO16:

      return &mt_elf_howto_table[ (int) R_MT_LO16];

    default:

      /* Pacify gcc -Wall.  */

      return NULL;

    }

  return NULL;

}

static reloc_howto_type *

mt_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,

          const char *r_name)

{

  unsigned int i;

  for (i = 0;

       i < sizeof (mt_elf_howto_table) / sizeof (mt_elf_howto_table[0]);

       i++)

    if (mt_elf_howto_table[i].name != NULL

  && strcasecmp (mt_elf_howto_table[i].name, r_name) == 0)

      return &mt_elf_howto_table[i];

  return NULL;

}

bfd_reloc_status_type

mt_elf_relocate_hi16

    (bfd *     input_bfd,

     Elf_Internal_Rela * relhi,

     bfd_byte *    contents,

     bfd_vma     value)

{

  bfd_vma insn;

  insn = bfd_get_32 (input_bfd, contents + relhi->r_offset);

  value += relhi->r_addend;

  value >>= 16;

  insn = ((insn & ~0xFFFF) | value);

  bfd_put_32 (input_bfd, insn, contents + relhi->r_offset);

  return bfd_reloc_ok;

}

/* XXX: The following code is the result of a cut&paste.  This unfortunate

   practice is very widespread in the various target back-end files.  */

/* Set the howto pointer for a MT ELF reloc.  */

static bool

mt_info_to_howto_rela (bfd *abfd,

           arelent *cache_ptr,

           Elf_Internal_Rela *dst)

{

  unsigned int r_type;

  r_type = ELF32_R_TYPE (dst->r_info);

  if (r_type >= (unsigned int) R_MT_max)

    {

      /* xgettext:c-format */

      _bfd_error_handler (_("%pB: unsupported relocation type %#x"),

        abfd, r_type);

      bfd_set_error (bfd_error_bad_value);

      return false;

    }

  cache_ptr->howto = & mt_elf_howto_table [r_type];

  return true;

}

/* Perform a single relocation.  By default we use the standard BFD

   routines.  */

static bfd_reloc_status_type

mt_final_link_relocate

    (reloc_howto_type *  howto,

     bfd *     input_bfd,

     asection *    input_section,

     bfd_byte *    contents,

     Elf_Internal_Rela * rel,

     bfd_vma     relocation)

{

  return _bfd_final_link_relocate (howto, input_bfd, input_section,

           contents, rel->r_offset,

           relocation, rel->r_addend);

}

/* Relocate a MT ELF section.

   There is some attempt to make this function usable for many architectures,

   both USE_REL and USE_RELA ['twould be nice if such a critter existed],

   if only to serve as a learning tool.

   The RELOCATE_SECTION function is called by the new ELF backend linker

   to handle the relocations for a section.

   The relocs are always passed as Rela structures; if the section

   actually uses Rel structures, the r_addend field will always be

   zero.

   This function is responsible for adjusting the section contents as

   necessary, and (if using Rela relocs and generating a relocatable

   output file) adjusting the reloc addend as necessary.

   This function does not have to worry about setting the reloc

   address or the reloc symbol index.

   LOCAL_SYMS is a pointer to the swapped in local symbols.

   LOCAL_SECTIONS is an array giving the section in the input file

   corresponding to the st_shndx field of each local symbol.

   The global hash table entry for the global symbols can be found

   via elf_sym_hashes (input_bfd).

   When generating relocatable output, this function must handle

   STB_LOCAL/STT_SECTION symbols specially.  The output symbol is

   going to be the section symbol corresponding to the output

   section, which means that the addend must be adjusted

   accordingly.  */

static int

mt_elf_relocate_section

    (bfd *         output_bfd ATTRIBUTE_UNUSED,

     struct bfd_link_info *  info,

     bfd *         input_bfd,

     asection *        input_section,

     bfd_byte *        contents,

     Elf_Internal_Rela *     relocs,

     Elf_Internal_Sym *      local_syms,

     asection **       local_sections)

{

  Elf_Internal_Shdr *   symtab_hdr;

  struct elf_link_hash_entry ** sym_hashes;

  Elf_Internal_Rela *   rel;

  Elf_Internal_Rela *   relend;

  symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;

  sym_hashes = elf_sym_hashes (input_bfd);

  relend     = relocs + input_section->reloc_count;

  for (rel = relocs; rel < relend; rel ++)

    {

      reloc_howto_type *     howto;

      unsigned long      r_symndx;

      Elf_Internal_Sym *     sym;

      asection *       sec;

      struct elf_link_hash_entry * h;

      bfd_vma        relocation;

      bfd_reloc_status_type    r;

      const char *       name = NULL;

      int        r_type;

      r_type = ELF32_R_TYPE (rel->r_info);

      r_symndx = ELF32_R_SYM (rel->r_info);

      howto  = mt_elf_howto_table + ELF32_R_TYPE (rel->r_info);

      h      = NULL;

      sym    = NULL;

      sec    = NULL;

      if (r_symndx < symtab_hdr->sh_info)

  {

    sym = local_syms + r_symndx;

    sec = local_sections [r_symndx];

    relocation = _bfd_elf_rela_local_sym (output_bfd, sym, &sec, rel);

    name = bfd_elf_string_from_elf_section

      (input_bfd, symtab_hdr->sh_link, sym->st_name);

    name = name == NULL ? bfd_section_name (sec) : name;

  }

      else

  {

    bool unresolved_reloc;

    bool warned, ignored;

    RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,

           r_symndx, symtab_hdr, sym_hashes,

           h, sec, relocation,

           unresolved_reloc, warned, ignored);

    name = h->root.root.string;

  }

      if (sec != NULL && discarded_section (sec))

  RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,

           rel, 1, relend, howto, 0, contents);

      if (bfd_link_relocatable (info))

  continue;

      /* Finally, the sole MT-specific part.  */

      switch (r_type)

  {

  case R_MT_HI16:

    r = mt_elf_relocate_hi16 (input_bfd, rel, contents, relocation);

    break;

  default:

    r = mt_final_link_relocate (howto, input_bfd, input_section,

            contents, rel, relocation);

    break;

  }

      if (r != bfd_reloc_ok)

  {

    const char * msg = (const char *) NULL;

    switch (r)

      {

      case bfd_reloc_overflow:

        (*info->callbacks->reloc_overflow)

    (info, (h ? &h->root : NULL), name, howto->name, (bfd_vma) 0,

     input_bfd, input_section, rel->r_offset);

        break;

      case bfd_reloc_undefined:

        (*info->callbacks->undefined_symbol)

    (info, name, input_bfd, input_section, rel->r_offset, true);

        break;

      case bfd_reloc_outofrange:

        msg = _("internal error: out of range error");

        break;

      case bfd_reloc_dangerous:

        msg = _("internal error: dangerous relocation");

        break;

      default:

        msg = _("internal error: unknown error");

        break;

      }

    if (msg)

      (*info->callbacks->warning) (info, msg, name, input_bfd,

           input_section, rel->r_offset);

  }

    }

  return true;

}

/* Look through the relocs for a section during the first phase.

   Since we don't do .gots or .plts, we just need to consider the

   virtual table relocs for gc.  */

static bool

mt_elf_check_relocs (bfd *abfd,

         struct bfd_link_info *info,

         asection *sec,

         const Elf_Internal_Rela *relocs)

{

  Elf_Internal_Shdr *symtab_hdr;

  struct elf_link_hash_entry **sym_hashes;

  const Elf_Internal_Rela *rel;

  const Elf_Internal_Rela *rel_end;

  if (bfd_link_relocatable (info))

    return true;

  symtab_hdr = &elf_tdata (abfd)->symtab_hdr;

  sym_hashes = elf_sym_hashes (abfd);

  rel_end = relocs + sec->reloc_count;

  for (rel = relocs; rel < rel_end; rel++)

    {

      struct elf_link_hash_entry *h;

      unsigned long r_symndx;

      r_symndx = ELF32_R_SYM (rel->r_info);

      if (r_symndx < symtab_hdr->sh_info)

  h = NULL;

      else

  {

    h = sym_hashes[r_symndx - symtab_hdr->sh_info];

    while (h->root.type == bfd_link_hash_indirect

     || h->root.type == bfd_link_hash_warning)

      h = (struct elf_link_hash_entry *) h->root.u.i.link;

  }

    }

  return true;

}

/* Return the MACH for an e_flags value.  */

static int

elf32_mt_machine (bfd *abfd)

{

  switch (elf_elfheader (abfd)->e_flags & EF_MT_CPU_MASK)

    {

    case EF_MT_CPU_MRISC: return bfd_mach_ms1;

    case EF_MT_CPU_MRISC2: return bfd_mach_mrisc2;

    case EF_MT_CPU_MS2:   return bfd_mach_ms2;

    }

  return bfd_mach_ms1;

}

static bool

mt_elf_object_p (bfd *abfd)

{

  bfd_default_set_arch_mach (abfd, bfd_arch_mt, elf32_mt_machine (abfd));

  return true;

}

/* Function to set the ELF flag bits.  */

static bool

mt_elf_set_private_flags (bfd *abfd, flagword flags)

{

  elf_elfheader (abfd)->e_flags = flags;

  elf_flags_init (abfd) = true;

  return true;

}

/* Merge backend specific data from an object file to the output

   object file when linking.  */

static bool

mt_elf_merge_private_bfd_data (bfd *ibfd, struct bfd_link_info *info)

{

  bfd *obfd = info->output_bfd;

  flagword old_flags, new_flags;

  bool ok = true;

  /* Check if we have the same endianness.  */

  if (!_bfd_generic_verify_endian_match (ibfd, info))

    return false;

  /* If they're not both mt, then merging is meaningless, so just

     don't do it.  */

  if (strcmp (ibfd->arch_info->arch_name, "mt") != 0)

    return true;

  if (strcmp (obfd->arch_info->arch_name, "mt") != 0)

    return true;

  new_flags = elf_elfheader (ibfd)->e_flags;

  old_flags = elf_elfheader (obfd)->e_flags;

#ifdef DEBUG

  _bfd_error_handler ("%pB: old_flags = 0x%.8x, new_flags = 0x%.8x, init = %s",

          ibfd, old_flags, new_flags, elf_flags_init (obfd) ? "yes" : "no");

#endif

  if (!elf_flags_init (obfd))

    {

      old_flags = new_flags;

      elf_flags_init (obfd) = true;

    }

  else if ((new_flags & EF_MT_CPU_MASK) != (old_flags & EF_MT_CPU_MASK))

    {

      /* CPU has changed.  This is invalid, because MRISC, MRISC2 and

   MS2 are not subsets of each other.   */

      ok = false;

    }

  if (ok)

    {

      obfd->arch_info = ibfd->arch_info;

      elf_elfheader (obfd)->e_flags = old_flags;

    }

  return ok;

}

static bool

mt_elf_print_private_bfd_data (bfd *abfd, void *ptr)

{

  FILE *file = (FILE *) ptr;

  flagword flags;

  BFD_ASSERT (abfd != NULL && ptr != NULL);

  /* Print normal ELF private data.  */

  _bfd_elf_print_private_bfd_data (abfd, ptr);

  flags = elf_elfheader (abfd)->e_flags;

  fprintf (file, _("private flags = 0x%lx:"), (unsigned long) flags);

  switch (flags & EF_MT_CPU_MASK)

    {

    default:

    case EF_MT_CPU_MRISC:   fprintf (file, " ms1-16-002");  break;

    case EF_MT_CPU_MRISC2:  fprintf (file, " ms1-16-003"); break;

    case EF_MT_CPU_MS2:     fprintf (file, " ms2"); break;

    }

  fputc ('\n', file);

  return true;

}

#define TARGET_BIG_SYM   mt_elf32_vec

#define TARGET_BIG_NAME  "elf32-mt"

#define ELF_ARCH   bfd_arch_mt

#define ELF_MACHINE_CODE EM_MT

#define ELF_MAXPAGESIZE  1 /* No pages on the MT.  */

#define elf_info_to_howto_rel     NULL

#define elf_info_to_howto     mt_info_to_howto_rela

#define elf_backend_relocate_section    mt_elf_relocate_section

#define bfd_elf32_bfd_reloc_type_lookup   mt_reloc_type_lookup

#define bfd_elf32_bfd_reloc_name_lookup   mt_reloc_name_lookup

#define elf_backend_check_relocs    mt_elf_check_relocs

#define elf_backend_object_p      mt_elf_object_p

#define elf_backend_rela_normal     1

#define elf_backend_can_gc_sections   1

#define bfd_elf32_bfd_set_private_flags   mt_elf_set_private_flags

#define bfd_elf32_bfd_merge_private_bfd_data  mt_elf_merge_private_bfd_data

#define bfd_elf32_bfd_print_private_bfd_data  mt_elf_print_private_bfd_data

#include "elf32-target.h"