/* SPARC-specific support for 32-bit ELF Copyright 1993 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 2 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "bfd.h" #include "sysdep.h" #include "bfdlink.h" #include "libbfd.h" #include "libelf.h" static CONST struct reloc_howto_struct *bfd_elf32_bfd_reloc_type_lookup PARAMS ((bfd *, bfd_reloc_code_real_type)); static void elf_info_to_howto PARAMS ((bfd *, arelent *, Elf_Internal_Rela *)); static boolean elf32_sparc_create_dynamic_sections PARAMS ((bfd *, struct bfd_link_info *)); static boolean elf32_sparc_create_got_section PARAMS ((bfd *, struct bfd_link_info *)); static boolean elf32_sparc_check_relocs PARAMS ((bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *)); static boolean elf32_sparc_adjust_dynamic_symbol PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *)); static boolean elf32_sparc_size_dynamic_sections PARAMS ((bfd *, struct bfd_link_info *)); static boolean elf32_sparc_relocate_section PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *, Elf_Internal_Rela *, Elf_Internal_Sym *, asection **)); static boolean elf32_sparc_finish_dynamic_symbol PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *, Elf_Internal_Sym *)); static boolean elf32_sparc_finish_dynamic_sections PARAMS ((bfd *, struct bfd_link_info *)); enum reloc_type { R_SPARC_NONE = 0, R_SPARC_8, R_SPARC_16, R_SPARC_32, R_SPARC_DISP8, R_SPARC_DISP16, R_SPARC_DISP32, R_SPARC_WDISP30, R_SPARC_WDISP22, R_SPARC_HI22, R_SPARC_22, R_SPARC_13, R_SPARC_LO10, R_SPARC_GOT10, R_SPARC_GOT13, R_SPARC_GOT22, R_SPARC_PC10, R_SPARC_PC22, R_SPARC_WPLT30, R_SPARC_COPY, R_SPARC_GLOB_DAT, R_SPARC_JMP_SLOT, R_SPARC_RELATIVE, R_SPARC_UA32, R_SPARC_max }; #if 0 static CONST char *CONST reloc_type_names[] = { "R_SPARC_NONE", "R_SPARC_8", "R_SPARC_16", "R_SPARC_32", "R_SPARC_DISP8", "R_SPARC_DISP16", "R_SPARC_DISP32", "R_SPARC_WDISP30", "R_SPARC_WDISP22", "R_SPARC_HI22", "R_SPARC_22", "R_SPARC_13", "R_SPARC_LO10", "R_SPARC_GOT10", "R_SPARC_GOT13", "R_SPARC_GOT22", "R_SPARC_PC10", "R_SPARC_PC22", "R_SPARC_WPLT30", "R_SPARC_COPY", "R_SPARC_GLOB_DAT", "R_SPARC_JMP_SLOT", "R_SPARC_RELATIVE", "R_SPARC_UA32", }; #endif static reloc_howto_type elf_sparc_howto_table[] = { HOWTO(R_SPARC_NONE, 0,0, 0,false,0,complain_overflow_dont, bfd_elf_generic_reloc,"R_SPARC_NONE", false,0,0x00000000,true), HOWTO(R_SPARC_8, 0,0, 8,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc,"R_SPARC_8", false,0,0x000000ff,true), HOWTO(R_SPARC_16, 0,1,16,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc,"R_SPARC_16", false,0,0x0000ffff,true), HOWTO(R_SPARC_32, 0,2,32,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc,"R_SPARC_32", false,0,0xffffffff,true), HOWTO(R_SPARC_DISP8, 0,0, 8,true, 0,complain_overflow_signed, bfd_elf_generic_reloc,"R_SPARC_DISP8", false,0,0x000000ff,true), HOWTO(R_SPARC_DISP16, 0,1,16,true, 0,complain_overflow_signed, bfd_elf_generic_reloc,"R_SPARC_DISP16", false,0,0x0000ffff,true), HOWTO(R_SPARC_DISP32, 0,2,32,true, 0,complain_overflow_signed, bfd_elf_generic_reloc,"R_SPARC_DISP32", false,0,0x00ffffff,true), HOWTO(R_SPARC_WDISP30, 2,2,30,true, 0,complain_overflow_signed, bfd_elf_generic_reloc,"R_SPARC_WDISP30", false,0,0x3fffffff,true), HOWTO(R_SPARC_WDISP22, 2,2,22,true, 0,complain_overflow_signed, bfd_elf_generic_reloc,"R_SPARC_WDISP22", false,0,0x003fffff,true), HOWTO(R_SPARC_HI22, 10,2,22,false,0,complain_overflow_dont, bfd_elf_generic_reloc,"R_SPARC_HI22", false,0,0x003fffff,true), HOWTO(R_SPARC_22, 0,2,22,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc,"R_SPARC_22", false,0,0x003fffff,true), HOWTO(R_SPARC_13, 0,2,13,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc,"R_SPARC_13", false,0,0x00001fff,true), HOWTO(R_SPARC_LO10, 0,2,10,false,0,complain_overflow_dont, bfd_elf_generic_reloc,"R_SPARC_LO10", false,0,0x000003ff,true), HOWTO(R_SPARC_GOT10, 0,2,10,false,0,complain_overflow_dont, bfd_elf_generic_reloc,"R_SPARC_GOT10", false,0,0x000003ff,true), HOWTO(R_SPARC_GOT13, 0,2,13,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc,"R_SPARC_GOT13", false,0,0x00001fff,true), HOWTO(R_SPARC_GOT22, 10,2,22,false,0,complain_overflow_dont, bfd_elf_generic_reloc,"R_SPARC_GOT22", false,0,0x003fffff,true), HOWTO(R_SPARC_PC10, 0,2,10,true, 0,complain_overflow_dont, bfd_elf_generic_reloc,"R_SPARC_PC10", false,0,0x000003ff,true), HOWTO(R_SPARC_PC22, 10,2,22,true, 0,complain_overflow_bitfield,bfd_elf_generic_reloc,"R_SPARC_PC22", false,0,0x003fffff,true), HOWTO(R_SPARC_WPLT30, 2,2,30,true, 0,complain_overflow_signed, bfd_elf_generic_reloc,"R_SPARC_WPLT30", false,0,0x3fffffff,true), HOWTO(R_SPARC_COPY, 0,0,00,false,0,complain_overflow_dont, bfd_elf_generic_reloc,"R_SPARC_COPY", false,0,0x00000000,true), HOWTO(R_SPARC_GLOB_DAT,0,0,00,false,0,complain_overflow_dont, bfd_elf_generic_reloc,"R_SPARC_GLOB_DAT",false,0,0x00000000,true), HOWTO(R_SPARC_JMP_SLOT,0,0,00,false,0,complain_overflow_dont, bfd_elf_generic_reloc,"R_SPARC_JMP_SLOT",false,0,0x00000000,true), HOWTO(R_SPARC_RELATIVE,0,0,00,false,0,complain_overflow_dont, bfd_elf_generic_reloc,"R_SPARC_RELATIVE",false,0,0x00000000,true), HOWTO(R_SPARC_UA32, 0,0,00,false,0,complain_overflow_dont, bfd_elf_generic_reloc,"R_SPARC_UA32", false,0,0x00000000,true), }; struct elf_reloc_map { unsigned char bfd_reloc_val; unsigned char elf_reloc_val; }; static CONST struct elf_reloc_map sparc_reloc_map[] = { { BFD_RELOC_NONE, R_SPARC_NONE, }, { BFD_RELOC_16, R_SPARC_16, }, { BFD_RELOC_8, R_SPARC_8 }, { BFD_RELOC_8_PCREL, R_SPARC_DISP8 }, { BFD_RELOC_CTOR, R_SPARC_32 }, /* @@ Assumes 32 bits. */ { BFD_RELOC_32, R_SPARC_32 }, { BFD_RELOC_32_PCREL, R_SPARC_DISP32 }, { BFD_RELOC_HI22, R_SPARC_HI22 }, { BFD_RELOC_LO10, R_SPARC_LO10, }, { BFD_RELOC_32_PCREL_S2, R_SPARC_WDISP30 }, { BFD_RELOC_SPARC22, R_SPARC_22 }, { BFD_RELOC_SPARC13, R_SPARC_13 }, { BFD_RELOC_SPARC_GOT10, R_SPARC_GOT10 }, { BFD_RELOC_SPARC_GOT13, R_SPARC_GOT13 }, { BFD_RELOC_SPARC_GOT22, R_SPARC_GOT22 }, { BFD_RELOC_SPARC_PC10, R_SPARC_PC10 }, { BFD_RELOC_SPARC_PC22, R_SPARC_PC22 }, { BFD_RELOC_SPARC_WPLT30, R_SPARC_WPLT30 }, { BFD_RELOC_SPARC_COPY, R_SPARC_COPY }, { BFD_RELOC_SPARC_GLOB_DAT, R_SPARC_GLOB_DAT }, { BFD_RELOC_SPARC_JMP_SLOT, R_SPARC_JMP_SLOT }, { BFD_RELOC_SPARC_RELATIVE, R_SPARC_RELATIVE }, { BFD_RELOC_SPARC_WDISP22, R_SPARC_WDISP22 }, /*{ BFD_RELOC_SPARC_UA32, R_SPARC_UA32 }, not used?? */ }; static CONST struct reloc_howto_struct * bfd_elf32_bfd_reloc_type_lookup (abfd, code) bfd *abfd; bfd_reloc_code_real_type code; { int i; for (i = 0; i < sizeof (sparc_reloc_map) / sizeof (struct elf_reloc_map); i++) { if (sparc_reloc_map[i].bfd_reloc_val == code) return &elf_sparc_howto_table[(int) sparc_reloc_map[i].elf_reloc_val]; } return 0; } static void elf_info_to_howto (abfd, cache_ptr, dst) bfd *abfd; arelent *cache_ptr; Elf_Internal_Rela *dst; { BFD_ASSERT (ELF32_R_TYPE(dst->r_info) < (unsigned int) R_SPARC_max); cache_ptr->howto = &elf_sparc_howto_table[ELF32_R_TYPE(dst->r_info)]; } /* Functions for the SPARC ELF linker. */ /* The name of the dynamic interpreter. This is put in the .interp section. */ #define ELF_DYNAMIC_INTERPRETER "/usr/lib/ld.so.1" /* The nop opcode we use. */ #define SPARC_NOP 0x01000000 /* The size in bytes of an entry in the procedure linkage table. */ #define PLT_ENTRY_SIZE 12 /* The first four entries in a procedure linkage table are reserved, and the initial contents are unimportant (we zero them out). Subsequent entries look like this. See the SVR4 ABI SPARC supplement to see how this works. */ /* sethi %hi(.-.plt0),%g1. We fill in the address later. */ #define PLT_ENTRY_WORD0 0x03000000 /* b,a .plt0. We fill in the offset later. */ #define PLT_ENTRY_WORD1 0x30800000 /* nop. */ #define PLT_ENTRY_WORD2 SPARC_NOP /* Create dynamic sections when linking against a dynamic object. */ static boolean elf32_sparc_create_dynamic_sections (abfd, info) bfd *abfd; struct bfd_link_info *info; { flagword flags; register asection *s; struct elf_link_hash_entry *h; /* We need to create .plt, .rela.plt, .got, .dynbss, and .rela.bss sections. */ flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY; s = bfd_make_section (abfd, ".plt"); if (s == NULL || ! bfd_set_section_flags (abfd, s, flags | SEC_CODE) || ! bfd_set_section_alignment (abfd, s, 2)) return false; /* Define the symbol _PROCEDURE_LINKAGE_TABLE_ at the start of the .plt section. */ h = NULL; if (! (_bfd_generic_link_add_one_symbol (info, abfd, "_PROCEDURE_LINKAGE_TABLE_", BSF_GLOBAL, s, (bfd_vma) 0, (const char *) NULL, false, get_elf_backend_data (abfd)->collect, (struct bfd_link_hash_entry **) &h))) return false; h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR; h->type = STT_OBJECT; if (info->shared && ! bfd_elf32_link_record_dynamic_symbol (info, h)) return false; s = bfd_make_section (abfd, ".rela.plt"); if (s == NULL || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY) || ! bfd_set_section_alignment (abfd, s, 2)) return false; if (! elf32_sparc_create_got_section (abfd, info)) return false; /* The .dynbss section is a place to put symbols which are defined by dynamic objects, are referenced by regular objects, and are not functions. We must allocate space for them in the process image and use a R_SPARC_COPY reloc to tell the dynamic linker to initialize them at run time. The linker script puts the .dynbss section into the .bss section of the final image. */ s = bfd_make_section (abfd, ".dynbss"); if (s == NULL || ! bfd_set_section_flags (abfd, s, SEC_ALLOC)) return false; /* The .rela.bss section holds copy relocs. */ if (! info->shared) { s = bfd_make_section (abfd, ".rela.bss"); if (s == NULL || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY) || ! bfd_set_section_alignment (abfd, s, 2)) return false; } return true; } /* Create the .got section to hold the global offset table. */ static boolean elf32_sparc_create_got_section (abfd, info) bfd *abfd; struct bfd_link_info *info; { register asection *s; struct elf_link_hash_entry *h; /* This function may be called more than once. */ if (bfd_get_section_by_name (abfd, ".got") != NULL) return true; s = bfd_make_section (abfd, ".got"); if (s == NULL || ! bfd_set_section_flags (abfd, s, (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY)) || ! bfd_set_section_alignment (abfd, s, 2)) return false; /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got section. We don't do this in the linker script because we don't want to define the symbol if we are not creating a global offset table. FIXME: The Solaris linker puts _GLOBAL_OFFSET_TABLE_ at the start of the .got section, but when using the small PIC model the .got is accessed using a signed 13 bit offset. Shouldn't _GLOBAL_OFFSET_TABLE_ be located at .got + 4096? */ h = NULL; if (! (_bfd_generic_link_add_one_symbol (info, abfd, "_GLOBAL_OFFSET_TABLE_", BSF_GLOBAL, s, (bfd_vma) 0, (const char *) NULL, false, get_elf_backend_data (abfd)->collect, (struct bfd_link_hash_entry **) &h))) return false; h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR; h->type = STT_OBJECT; if (info->shared && ! bfd_elf32_link_record_dynamic_symbol (info, h)) return false; /* The first global offset table entry is reserved. */ s->_raw_size += 4; return true; } /* Look through the relocs for a section during the first phase, and allocate space in the global offset table or procedure linkage table. */ static boolean elf32_sparc_check_relocs (abfd, info, sec, relocs) bfd *abfd; struct bfd_link_info *info; asection *sec; const Elf_Internal_Rela *relocs; { bfd *dynobj; Elf_Internal_Shdr *symtab_hdr; struct elf_link_hash_entry **sym_hashes; bfd_vma *local_got_offsets; const Elf_Internal_Rela *rel; const Elf_Internal_Rela *rel_end; asection *sgot; asection *srelgot; asection *sreloc; if (info->relocateable) return true; dynobj = elf_hash_table (info)->dynobj; symtab_hdr = &elf_tdata (abfd)->symtab_hdr; sym_hashes = elf_sym_hashes (abfd); local_got_offsets = elf_local_got_offsets (abfd); sgot = NULL; srelgot = NULL; sreloc = NULL; rel_end = relocs + sec->reloc_count; for (rel = relocs; rel < rel_end; rel++) { long r_symndx; struct elf_link_hash_entry *h; 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]; switch (ELF32_R_TYPE (rel->r_info)) { case R_SPARC_GOT10: case R_SPARC_GOT13: case R_SPARC_GOT22: /* This symbol requires a global offset table entry. */ if (dynobj == NULL) { /* Create the .got section. */ elf_hash_table (info)->dynobj = dynobj = abfd; if (! elf32_sparc_create_got_section (dynobj, info)) return false; } if (sgot == NULL) { sgot = bfd_get_section_by_name (dynobj, ".got"); BFD_ASSERT (sgot != NULL); } if (srelgot == NULL && (h != NULL || info->shared)) { srelgot = bfd_get_section_by_name (dynobj, ".rela.got"); if (srelgot == NULL) { srelgot = bfd_make_section (dynobj, ".rela.got"); if (srelgot == NULL || ! bfd_set_section_flags (dynobj, srelgot, (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_READONLY)) || ! bfd_set_section_alignment (dynobj, srelgot, 2)) return false; } } if (h != NULL) { if (h->got_offset != (bfd_vma) -1) { /* We have already allocated space in the .got. */ break; } h->got_offset = sgot->_raw_size; /* Make sure this symbol is output as a dynamic symbol. */ if (h->dynindx == -1) { if (! bfd_elf32_link_record_dynamic_symbol (info, h)) return false; } srelgot->_raw_size += sizeof (Elf32_External_Rela); } else { /* This is a global offset table entry for a local symbol. */ if (local_got_offsets == NULL) { size_t size; register int i; size = symtab_hdr->sh_info * sizeof (bfd_vma); local_got_offsets = (bfd_vma *) bfd_alloc (abfd, size); if (local_got_offsets == NULL) { bfd_set_error (bfd_error_no_memory); return false; } elf_local_got_offsets (abfd) = local_got_offsets; for (i = 0; i < symtab_hdr->sh_info; i++) local_got_offsets[i] = (bfd_vma) -1; } if (local_got_offsets[r_symndx] != (bfd_vma) -1) { /* We have already allocated space in the .got. */ break; } local_got_offsets[r_symndx] = sgot->_raw_size; if (info->shared) { /* If we are generating a shared object, we need to output a R_SPARC_RELATIVE reloc so that the dynamic linker can adjust this GOT entry. */ srelgot->_raw_size += sizeof (Elf32_External_Rela); } } sgot->_raw_size += 4; break; case R_SPARC_WPLT30: /* This symbol requires a procedure linkage table entry. We actually build the entry in adjust_dynamic_symbol, because this might be a case of linking PIC code without linking in any dynamic objects, in which case we don't need to generate a procedure linkage table after all. */ if (h == NULL) { /* It does not make sense to have a procedure linkage table entry for a local symbol. */ bfd_set_error (bfd_error_bad_value); return false; } /* Make sure this symbol is output as a dynamic symbol. */ if (h->dynindx == -1) { if (! bfd_elf32_link_record_dynamic_symbol (info, h)) return false; } h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT; break; case R_SPARC_PC10: case R_SPARC_PC22: if (h != NULL && strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0) break; /* Fall through. */ case R_SPARC_8: case R_SPARC_16: case R_SPARC_32: case R_SPARC_DISP8: case R_SPARC_DISP16: case R_SPARC_DISP32: case R_SPARC_WDISP30: case R_SPARC_WDISP22: case R_SPARC_HI22: case R_SPARC_22: case R_SPARC_13: case R_SPARC_LO10: case R_SPARC_UA32: if (info->shared && (sec->flags & SEC_ALLOC) != 0) { /* When creating a shared object, we must copy these relocs into the output file. We create a reloc section in dynobj and make room for the reloc. */ if (sreloc == NULL) { const char *name; name = (elf_string_from_elf_section (abfd, elf_elfheader (abfd)->e_shstrndx, elf_section_data (sec)->rel_hdr.sh_name)); if (name == NULL) return false; BFD_ASSERT (strncmp (name, ".rela", 5) == 0 && strcmp (bfd_get_section_name (abfd, sec), name + 5) == 0); sreloc = bfd_get_section_by_name (dynobj, name); if (sreloc == NULL) { sreloc = bfd_make_section (dynobj, name); if (sreloc == NULL || ! bfd_set_section_flags (dynobj, sreloc, (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_READONLY)) || ! bfd_set_section_alignment (dynobj, sreloc, 2)) return false; } } sreloc->_raw_size += sizeof (Elf32_External_Rela); } break; default: break; } } return true; } /* Adjust a symbol defined by a dynamic object and referenced by a regular object. The current definition is in some section of the dynamic object, but we're not including those sections. We have to change the definition to something the rest of the link can understand. */ static boolean elf32_sparc_adjust_dynamic_symbol (info, h) struct bfd_link_info *info; struct elf_link_hash_entry *h; { bfd *dynobj; asection *s; unsigned int power_of_two; dynobj = elf_hash_table (info)->dynobj; /* Make sure we know what is going on here. */ BFD_ASSERT (dynobj != NULL && ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) || ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0 && h->root.type == bfd_link_hash_defined && (bfd_get_flavour (h->root.u.def.section->owner) == bfd_target_elf_flavour) && (elf_elfheader (h->root.u.def.section->owner)->e_type == ET_DYN) && h->root.u.def.section->output_section == NULL))); /* If this is a function, put it in the procedure linkage table. We will fill in the contents of the procedure linkage table later (although we could actually do it here). */ if (h->type == STT_FUNC || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0) { if (! elf_hash_table (info)->dynamic_sections_created) { /* This case can occur if we saw a WPLT30 reloc in an input file, but none of the input files were dynamic objects. In such a case, we don't actually need to build a procedure linkage table, and we can just do a WDISP30 reloc instead. */ BFD_ASSERT ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0); return true; } s = bfd_get_section_by_name (dynobj, ".plt"); BFD_ASSERT (s != NULL); /* The first four entries in .plt are reserved. */ if (s->_raw_size == 0) s->_raw_size = 4 * PLT_ENTRY_SIZE; /* The procedure linkage table has a maximum size. */ if (s->_raw_size >= 0x400000) { bfd_set_error (bfd_error_bad_value); return false; } /* Set the symbol to this location in the .plt. */ h->root.u.def.section = s; h->root.u.def.value = s->_raw_size; h->plt_offset = s->_raw_size; /* Make room for this entry. */ s->_raw_size += PLT_ENTRY_SIZE; /* We also need to make an entry in the .rela.plt section. */ s = bfd_get_section_by_name (dynobj, ".rela.plt"); BFD_ASSERT (s != NULL); s->_raw_size += sizeof (Elf32_External_Rela); return true; } /* If this is a weak symbol, and there is a real definition, the processor independent code will have arranged for us to see the real definition first, and we can just use the same value. */ if (h->weakdef != NULL) { BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined); h->root.u.def.section = h->weakdef->root.u.def.section; h->root.u.def.value = h->weakdef->root.u.def.value; return true; } /* This is a reference to a symbol defined by a dynamic object which is not a function. */ /* If we are creating a shared library, we must presume that the only references to the symbol are via the global offset table. For such cases we need not do anything here; the relocations will be handled correctly by relocate_section. */ if (info->shared) return true; /* We must allocate the symbol in our .dynbss section, which will become part of the .bss section of the executable. There will be an entry for this symbol in the .dynsym section. The dynamic object will contain position independent code, so all references from the dynamic object to this symbol will go through the global offset table. The dynamic linker will use the .dynsym entry to determine the address it must put in the global offset table, so both the dynamic object and the regular object will refer to the same memory location for the variable. */ s = bfd_get_section_by_name (dynobj, ".dynbss"); BFD_ASSERT (s != NULL); /* If the symbol is currently defined in the .bss section of the dynamic object, then it is OK to simply initialize it to zero. If the symbol is in some other section, we must generate a R_SPARC_COPY reloc to tell the dynamic linker to copy the initial value out of the dynamic object and into the runtime process image. We need to remember the offset into the .rel.bss section we are going to use. */ if ((h->root.u.def.section->flags & SEC_LOAD) != 0) { asection *srel; srel = bfd_get_section_by_name (dynobj, ".rela.bss"); BFD_ASSERT (srel != NULL); srel->_raw_size += sizeof (Elf32_External_Rela); h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY; } /* We need to figure out the alignment required for this symbol. I have no idea how ELF linkers handle this. */ power_of_two = bfd_log2 (h->size); if (power_of_two > 3) power_of_two = 3; /* Apply the required alignment. */ s->_raw_size = BFD_ALIGN (s->_raw_size, (bfd_size_type) (1 << power_of_two)); if (power_of_two > bfd_get_section_alignment (dynobj, s)) { if (! bfd_set_section_alignment (dynobj, s, power_of_two)) return false; } /* Define the symbol as being at this point in the section. */ h->root.u.def.section = s; h->root.u.def.value = s->_raw_size; /* Increment the section size to make room for the symbol. */ s->_raw_size += h->size; return true; } /* Set the sizes of the dynamic sections. */ static boolean elf32_sparc_size_dynamic_sections (output_bfd, info) bfd *output_bfd; struct bfd_link_info *info; { bfd *dynobj; asection *s; boolean reltext; dynobj = elf_hash_table (info)->dynobj; BFD_ASSERT (dynobj != NULL); if (elf_hash_table (info)->dynamic_sections_created) { /* Set the contents of the .interp section to the interpreter. */ if (! info->shared) { s = bfd_get_section_by_name (dynobj, ".interp"); BFD_ASSERT (s != NULL); s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER; s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER; } /* Make space for the trailing nop in .plt. */ s = bfd_get_section_by_name (dynobj, ".plt"); BFD_ASSERT (s != NULL); if (s->_raw_size > 0) s->_raw_size += 4; } else { /* We may have created entries in the .rela.got section. However, if we are not creating the dynamic sections, we will not actually use these entries. Reset the size of .rela.got, which will cause it to get stripped from the output file below. */ s = bfd_get_section_by_name (dynobj, ".rela.got"); if (s != NULL) s->_raw_size = 0; } /* The check_relocs and adjust_dynamic_symbol entry points have determined the sizes of the various dynamic sections. Allocate memory for them. */ reltext = false; for (s = dynobj->sections; s != NULL; s = s->next) { const char *name; boolean strip; if ((s->flags & SEC_IN_MEMORY) == 0) continue; /* It's OK to base decisions on the section name, because none of the dynobj section names depend upon the input files. */ name = bfd_get_section_name (dynobj, s); strip = false; if (strncmp (name, ".rela", 5) == 0) { if (s->_raw_size == 0) { /* If we don't need this section, strip it from the output file. This is to handle .rela.bss and .rel.plt. We must create it in create_dynamic_sections, because it must be created before the linker maps input sections to output sections. The linker does that before adjust_dynamic_symbol is called, and it is that function which decides whether anything needs to go into these sections. */ strip = true; } else { asection *target; /* If this relocation section applies to a read only section, then we probably need a DT_TEXTREL entry. */ target = bfd_get_section_by_name (output_bfd, name + 5); if (target != NULL && (target->flags & SEC_READONLY) != 0) reltext = true; /* We use the reloc_count field as a counter if we need to copy relocs into the output file. */ s->reloc_count = 0; } } else if (strcmp (name, ".plt") != 0 && strcmp (name, ".got") != 0) { /* It's not one of our sections, so don't allocate space. */ continue; } if (strip) { asection **spp; for (spp = &s->output_section->owner->sections; *spp != s->output_section; spp = &(*spp)->next) ; *spp = s->output_section->next; --s->output_section->owner->section_count; continue; } /* Allocate memory for the section contents. */ s->contents = (bfd_byte *) bfd_alloc (dynobj, s->_raw_size); if (s->contents == NULL && s->_raw_size != 0) { bfd_set_error (bfd_error_no_memory); return false; } } if (elf_hash_table (info)->dynamic_sections_created) { /* Add some entries to the .dynamic section. We fill in the values later, in elf32_sparc_finish_dynamic_sections, but we must add the entries now so that we get the correct size for the .dynamic section. The DT_DEBUG entry is filled in by the dynamic linker and used by the debugger. */ if (! info->shared) { if (! bfd_elf32_add_dynamic_entry (info, DT_DEBUG, 0)) return false; } if (! bfd_elf32_add_dynamic_entry (info, DT_PLTGOT, 0) || ! bfd_elf32_add_dynamic_entry (info, DT_PLTRELSZ, 0) || ! bfd_elf32_add_dynamic_entry (info, DT_PLTREL, DT_RELA) || ! bfd_elf32_add_dynamic_entry (info, DT_JMPREL, 0) || ! bfd_elf32_add_dynamic_entry (info, DT_RELA, 0) || ! bfd_elf32_add_dynamic_entry (info, DT_RELASZ, 0) || ! bfd_elf32_add_dynamic_entry (info, DT_RELAENT, sizeof (Elf32_External_Rela))) return false; if (reltext) { if (! bfd_elf32_add_dynamic_entry (info, DT_TEXTREL, 0)) return false; } } return true; } /* Relocate a SPARC ELF section. */ static boolean elf32_sparc_relocate_section (output_bfd, info, input_bfd, input_section, contents, relocs, local_syms, local_sections) bfd *output_bfd; 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; { bfd *dynobj; Elf_Internal_Shdr *symtab_hdr; struct elf_link_hash_entry **sym_hashes; bfd_vma *local_got_offsets; asection *sgot; asection *splt; asection *sreloc; Elf_Internal_Rela *rel; Elf_Internal_Rela *relend; dynobj = elf_hash_table (info)->dynobj; symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr; sym_hashes = elf_sym_hashes (input_bfd); local_got_offsets = elf_local_got_offsets (input_bfd); sgot = NULL; splt = NULL; sreloc = NULL; rel = relocs; relend = relocs + input_section->reloc_count; for (; rel < relend; rel++) { int r_type; const reloc_howto_type *howto; long r_symndx; struct elf_link_hash_entry *h; Elf_Internal_Sym *sym; asection *sec; bfd_vma relocation; bfd_reloc_status_type r; r_type = ELF32_R_TYPE (rel->r_info); if (r_type < 0 || r_type >= (int) R_SPARC_max) { bfd_set_error (bfd_error_bad_value); return false; } howto = elf_sparc_howto_table + r_type; r_symndx = ELF32_R_SYM (rel->r_info); if (info->relocateable) { /* This is a relocateable link. We don't have to change anything, unless the reloc is against a section symbol, in which case we have to adjust according to where the section symbol winds up in the output section. */ if (r_symndx < symtab_hdr->sh_info) { sym = local_syms + r_symndx; if (ELF_ST_TYPE (sym->st_info) == STT_SECTION) { sec = local_sections[r_symndx]; rel->r_addend += sec->output_offset + sym->st_value; } } continue; } /* This is a final link. */ h = NULL; sym = NULL; sec = NULL; if (r_symndx < symtab_hdr->sh_info) { sym = local_syms + r_symndx; sec = local_sections[r_symndx]; relocation = (sec->output_section->vma + sec->output_offset + sym->st_value); } else { h = sym_hashes[r_symndx - symtab_hdr->sh_info]; if (h->root.type == bfd_link_hash_defined) { sec = h->root.u.def.section; relocation = (h->root.u.def.value + sec->output_section->vma + sec->output_offset); } else if (h->root.type == bfd_link_hash_weak) relocation = 0; else if (info->shared) relocation = 0; else { if (! ((*info->callbacks->undefined_symbol) (info, h->root.root.string, input_bfd, input_section, rel->r_offset))) return false; relocation = 0; } } switch (r_type) { case R_SPARC_GOT10: case R_SPARC_GOT13: case R_SPARC_GOT22: /* Relocation is to the entry for this symbol in the global offset table. */ if (sgot == NULL) { sgot = bfd_get_section_by_name (dynobj, ".got"); BFD_ASSERT (sgot != NULL); } if (h != NULL) { bfd_vma off; off = h->got_offset; BFD_ASSERT (off != (bfd_vma) -1); if (! elf_hash_table (info)->dynamic_sections_created) { /* This is actually a static link. We must initialize this entry in the global offset table. Since the offset must always be a multiple of 4, we use the least significant bit to record whether we have initialized it already. When doing a dynamic link, we create a .rela.got relocation entry to initialize the value. This is done in the finish_dynamic_symbol routine. */ if ((off & 1) != 0) off &= ~1; else { bfd_put_32 (output_bfd, relocation, sgot->contents + off); h->got_offset |= 1; } } relocation = sgot->output_offset + off; } else { bfd_vma off; BFD_ASSERT (local_got_offsets != NULL && local_got_offsets[r_symndx] != (bfd_vma) -1); off = local_got_offsets[r_symndx]; /* The offset must always be a multiple of 4. We use the least significant bit to record whether we have already processed this entry. */ if ((off & 1) != 0) off &= ~1; else { bfd_put_32 (output_bfd, relocation, sgot->contents + off); if (info->shared) { asection *srelgot; Elf_Internal_Rela outrel; /* We need to generate a R_SPARC_RELATIVE reloc for the dynamic linker. */ srelgot = bfd_get_section_by_name (dynobj, ".rela.got"); BFD_ASSERT (srelgot != NULL); outrel.r_offset = (sgot->output_section->vma + sgot->output_offset + off); outrel.r_info = ELF32_R_INFO (0, R_SPARC_RELATIVE); outrel.r_addend = 0; bfd_elf32_swap_reloca_out (output_bfd, &outrel, (((Elf32_External_Rela *) srelgot->contents) + srelgot->reloc_count)); ++srelgot->reloc_count; } local_got_offsets[r_symndx] |= 1; } relocation = sgot->output_offset + off; } break; case R_SPARC_WPLT30: /* Relocation is to the entry for this symbol in the procedure linkage table. */ BFD_ASSERT (h != NULL); if (h->plt_offset == (bfd_vma) -1) { /* We didn't make a PLT entry for this symbol. This happens when statically linking PIC code. */ break; } if (splt == NULL) { splt = bfd_get_section_by_name (dynobj, ".plt"); BFD_ASSERT (splt != NULL); } relocation = (splt->output_section->vma + splt->output_offset + h->plt_offset); break; case R_SPARC_PC10: case R_SPARC_PC22: if (h != NULL && strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0) break; /* Fall through. */ case R_SPARC_8: case R_SPARC_16: case R_SPARC_32: case R_SPARC_DISP8: case R_SPARC_DISP16: case R_SPARC_DISP32: case R_SPARC_WDISP30: case R_SPARC_WDISP22: case R_SPARC_HI22: case R_SPARC_22: case R_SPARC_13: case R_SPARC_LO10: case R_SPARC_UA32: if (info->shared && (input_section->flags & SEC_ALLOC) != 0) { Elf_Internal_Rela outrel; /* When generating a shared object, these relocations are copied into the output file to be resolved at run time. */ if (sreloc == NULL) { const char *name; name = (elf_string_from_elf_section (input_bfd, elf_elfheader (input_bfd)->e_shstrndx, elf_section_data (input_section)->rel_hdr.sh_name)); if (name == NULL) return false; BFD_ASSERT (strncmp (name, ".rela", 5) == 0 && strcmp (bfd_get_section_name (input_bfd, input_section), name + 5) == 0); sreloc = bfd_get_section_by_name (dynobj, name); BFD_ASSERT (sreloc != NULL); } outrel.r_offset = (rel->r_offset + input_section->output_section->vma + input_section->output_offset); if (h != NULL) { BFD_ASSERT (h->dynindx != -1); outrel.r_info = ELF32_R_INFO (h->dynindx, r_type); outrel.r_addend = 0; } else { long indx; sym = local_syms + r_symndx; /* If this isn't a section symbol, we need to map it to something that is going to be put into the dynamic symbols. The case will probably never arise. */ BFD_ASSERT (ELF_ST_TYPE (sym->st_info) == STT_SECTION); sec = local_sections[r_symndx]; if (sec != NULL && bfd_is_abs_section (sec)) indx = 0; else if (sec == NULL || sec->owner == NULL) { bfd_set_error (bfd_error_bad_value); return false; } else { indx = sec->output_section->target_index; if (indx == 0) abort (); } outrel.r_info = ELF32_R_INFO (indx, r_type); outrel.r_addend = sec->output_offset + sym->st_value; } bfd_elf32_swap_reloca_out (output_bfd, &outrel, (((Elf32_External_Rela *) sreloc->contents) + sreloc->reloc_count)); ++sreloc->reloc_count; /* This reloc will be computed at runtime, so there's no need to do anything now. */ continue; } default: break; } r = _bfd_final_link_relocate (howto, input_bfd, input_section, contents, rel->r_offset, relocation, rel->r_addend); if (r != bfd_reloc_ok) { switch (r) { default: case bfd_reloc_outofrange: abort (); case bfd_reloc_overflow: { const char *name; if (h != NULL) name = h->root.root.string; else { name = elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link, sym->st_name); if (name == NULL) return false; if (*name == '\0') name = bfd_section_name (input_bfd, sec); } if (! ((*info->callbacks->reloc_overflow) (info, name, howto->name, (bfd_vma) 0, input_bfd, input_section, rel->r_offset))) return false; } break; } } } return true; } /* Finish up dynamic symbol handling. We set the contents of various dynamic sections here. */ static boolean elf32_sparc_finish_dynamic_symbol (output_bfd, info, h, sym) bfd *output_bfd; struct bfd_link_info *info; struct elf_link_hash_entry *h; Elf_Internal_Sym *sym; { bfd *dynobj; dynobj = elf_hash_table (info)->dynobj; if (h->plt_offset != (bfd_vma) -1) { asection *splt; asection *srela; Elf_Internal_Rela rela; /* This symbol has an entry in the procedure linkage table. Set it up. */ BFD_ASSERT (h->dynindx != -1); splt = bfd_get_section_by_name (dynobj, ".plt"); srela = bfd_get_section_by_name (dynobj, ".rela.plt"); BFD_ASSERT (splt != NULL && srela != NULL); /* Fill in the entry in the procedure linkage table. */ bfd_put_32 (output_bfd, PLT_ENTRY_WORD0 + h->plt_offset, splt->contents + h->plt_offset); bfd_put_32 (output_bfd, (PLT_ENTRY_WORD1 + (((- (h->plt_offset + 4)) >> 2) & 0x3fffff)), splt->contents + h->plt_offset + 4); bfd_put_32 (output_bfd, PLT_ENTRY_WORD2, splt->contents + h->plt_offset + 8); /* Fill in the entry in the .rela.plt section. */ rela.r_offset = (splt->output_section->vma + splt->output_offset + h->plt_offset); rela.r_info = ELF32_R_INFO (h->dynindx, R_SPARC_JMP_SLOT); rela.r_addend = 0; bfd_elf32_swap_reloca_out (output_bfd, &rela, ((Elf32_External_Rela *) srela->contents + h->plt_offset / PLT_ENTRY_SIZE - 4)); if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0) { /* Mark the symbol as undefined, rather than as defined in the .plt section. Leave the value alone. */ sym->st_shndx = SHN_UNDEF; } } if (h->got_offset != (bfd_vma) -1) { asection *sgot; asection *srela; Elf_Internal_Rela rela; /* This symbol has an entry in the global offset table. Set it up. */ BFD_ASSERT (h->dynindx != -1); sgot = bfd_get_section_by_name (dynobj, ".got"); srela = bfd_get_section_by_name (dynobj, ".rela.got"); BFD_ASSERT (sgot != NULL && srela != NULL); bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + h->got_offset); rela.r_offset = (sgot->output_section->vma + sgot->output_offset + h->got_offset); rela.r_info = ELF32_R_INFO (h->dynindx, R_SPARC_GLOB_DAT); rela.r_addend = 0; bfd_elf32_swap_reloca_out (output_bfd, &rela, ((Elf32_External_Rela *) srela->contents + srela->reloc_count)); ++srela->reloc_count; } if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0) { asection *s; Elf_Internal_Rela rela; /* This symbols needs a copy reloc. Set it up. */ BFD_ASSERT (h->dynindx != -1); s = bfd_get_section_by_name (h->root.u.def.section->owner, ".rela.bss"); BFD_ASSERT (s != NULL); rela.r_offset = (h->root.u.def.value + h->root.u.def.section->output_section->vma + h->root.u.def.section->output_offset); rela.r_info = ELF32_R_INFO (h->dynindx, R_SPARC_COPY); rela.r_addend = 0; bfd_elf32_swap_reloca_out (output_bfd, &rela, ((Elf32_External_Rela *) s->contents + s->reloc_count)); ++s->reloc_count; } /* Mark some specially defined symbols as absolute. */ if (strcmp (h->root.root.string, "_DYNAMIC") == 0 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0 || strcmp (h->root.root.string, "_PROCEDURE_LINKAGE_TABLE_") == 0) sym->st_shndx = SHN_ABS; return true; } /* Finish up the dynamic sections. */ static boolean elf32_sparc_finish_dynamic_sections (output_bfd, info) bfd *output_bfd; struct bfd_link_info *info; { bfd *dynobj; asection *sdyn; asection *sgot; dynobj = elf_hash_table (info)->dynobj; sdyn = bfd_get_section_by_name (dynobj, ".dynamic"); if (elf_hash_table (info)->dynamic_sections_created) { asection *splt; Elf32_External_Dyn *dyncon, *dynconend; splt = bfd_get_section_by_name (dynobj, ".plt"); BFD_ASSERT (splt != NULL && sdyn != NULL); dyncon = (Elf32_External_Dyn *) sdyn->contents; dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size); for (; dyncon < dynconend; dyncon++) { Elf_Internal_Dyn dyn; const char *name; boolean size; bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn); switch (dyn.d_tag) { case DT_PLTGOT: name = ".plt"; size = false; break; case DT_PLTRELSZ: name = ".rela.plt"; size = true; break; case DT_JMPREL: name = ".rela.plt"; size = false; break; default: name = NULL; size = false; break; } if (name != NULL) { asection *s; s = bfd_get_section_by_name (output_bfd, name); BFD_ASSERT (s != NULL); if (! size) dyn.d_un.d_ptr = s->vma; else { if (s->_cooked_size != 0) dyn.d_un.d_val = s->_cooked_size; else dyn.d_un.d_val = s->_raw_size; } bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon); } } /* Clear the first four entries in the procedure linkage table, and put a nop in the last four bytes. */ if (splt->_raw_size > 0) { memset (splt->contents, 0, 4 * PLT_ENTRY_SIZE); bfd_put_32 (output_bfd, SPARC_NOP, splt->contents + splt->_raw_size - 4); } elf_section_data (splt->output_section)->this_hdr.sh_entsize = PLT_ENTRY_SIZE; } /* Set the first entry in the global offset table to the address of the dynamic section. */ sgot = bfd_get_section_by_name (dynobj, ".got"); BFD_ASSERT (sgot != NULL); if (sgot->_raw_size > 0) { if (sdyn == NULL) bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents); else bfd_put_32 (output_bfd, sdyn->output_section->vma + sdyn->output_offset, sgot->contents); } elf_section_data (sgot->output_section)->this_hdr.sh_entsize = 4; return true; } #define TARGET_BIG_SYM bfd_elf32_sparc_vec #define TARGET_BIG_NAME "elf32-sparc" #define ELF_ARCH bfd_arch_sparc #define ELF_MACHINE_CODE EM_SPARC #define ELF_MAXPAGESIZE 0x10000 #define elf_backend_create_dynamic_sections \ elf32_sparc_create_dynamic_sections #define elf_backend_check_relocs elf32_sparc_check_relocs #define elf_backend_adjust_dynamic_symbol \ elf32_sparc_adjust_dynamic_symbol #define elf_backend_size_dynamic_sections \ elf32_sparc_size_dynamic_sections #define elf_backend_relocate_section elf32_sparc_relocate_section #define elf_backend_finish_dynamic_symbol \ elf32_sparc_finish_dynamic_symbol #define elf_backend_finish_dynamic_sections \ elf32_sparc_finish_dynamic_sections #include "elf32-target.h"