elf32-sparc.c
来自「基于4个mips核的noc设计」· C语言 代码 · 共 2,014 行 · 第 1/5 页
C
2,014 行
/* SPARC-specific support for 32-bit ELF Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001 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 modifyit under the terms of the GNU General Public License as published bythe 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 ofMERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See theGNU General Public License for more details.You should have received a copy of the GNU General Public Licensealong with this program; if not, write to the Free SoftwareFoundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */#include "bfd.h"#include "sysdep.h"#include "bfdlink.h"#include "libbfd.h"#include "elf-bfd.h"#include "elf/sparc.h"#include "opcode/sparc.h"static reloc_howto_type *elf32_sparc_reloc_type_lookup PARAMS ((bfd *, bfd_reloc_code_real_type));static void elf32_sparc_info_to_howto PARAMS ((bfd *, arelent *, Elf_Internal_Rela *));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_relax_section PARAMS ((bfd *, asection *, struct bfd_link_info *, boolean *));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 *));static boolean elf32_sparc_merge_private_bfd_data PARAMS ((bfd *, bfd *));static boolean elf32_sparc_object_p PARAMS ((bfd *));static void elf32_sparc_final_write_processing PARAMS ((bfd *, boolean));/* The relocation "howto" table. */static bfd_reloc_status_type sparc_elf_notsupported_reloc PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **));static bfd_reloc_status_type sparc_elf_wdisp16_reloc PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **));reloc_howto_type _bfd_sparc_elf_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_signed, 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, 0,2,32,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc, "R_SPARC_UA32", false,0,0xffffffff,true), HOWTO(R_SPARC_PLT32, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_PLT32", false,0,0x00000000,true), HOWTO(R_SPARC_HIPLT22, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_HIPLT22", false,0,0x00000000,true), HOWTO(R_SPARC_LOPLT10, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_LOPLT10", false,0,0x00000000,true), HOWTO(R_SPARC_PCPLT32, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_PCPLT32", false,0,0x00000000,true), HOWTO(R_SPARC_PCPLT22, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_PCPLT22", false,0,0x00000000,true), HOWTO(R_SPARC_PCPLT10, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_PCPLT10", false,0,0x00000000,true), HOWTO(R_SPARC_10, 0,2,10,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc, "R_SPARC_10", false,0,0x000003ff,true), HOWTO(R_SPARC_11, 0,2,11,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc, "R_SPARC_11", false,0,0x000007ff,true), /* These are for sparc64 in a 64 bit environment. Values need to be here because the table is indexed by reloc number. */ HOWTO(R_SPARC_64, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_64", false,0,0x00000000,true), HOWTO(R_SPARC_OLO10, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_OLO10", false,0,0x00000000,true), HOWTO(R_SPARC_HH22, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_HH22", false,0,0x00000000,true), HOWTO(R_SPARC_HM10, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_HM10", false,0,0x00000000,true), HOWTO(R_SPARC_LM22, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_LM22", false,0,0x00000000,true), HOWTO(R_SPARC_PC_HH22, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_PC_HH22", false,0,0x00000000,true), HOWTO(R_SPARC_PC_HM10, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_PC_HM10", false,0,0x00000000,true), HOWTO(R_SPARC_PC_LM22, 0,0,00,false,0,complain_overflow_dont, sparc_elf_notsupported_reloc, "R_SPARC_PC_LM22", false,0,0x00000000,true), /* End sparc64 in 64 bit environment values. The following are for sparc64 in a 32 bit environment. */ HOWTO(R_SPARC_WDISP16, 2,2,16,true, 0,complain_overflow_signed, sparc_elf_wdisp16_reloc,"R_SPARC_WDISP16", false,0,0x00000000,true), HOWTO(R_SPARC_WDISP19, 2,2,19,true, 0,complain_overflow_signed, bfd_elf_generic_reloc, "R_SPARC_WDISP19", false,0,0x0007ffff,true), HOWTO(R_SPARC_UNUSED_42, 0,0, 0,false,0,complain_overflow_dont, bfd_elf_generic_reloc, "R_SPARC_UNUSED_42",false,0,0x00000000,true), HOWTO(R_SPARC_7, 0,2, 7,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc, "R_SPARC_7", false,0,0x0000007f,true), HOWTO(R_SPARC_5, 0,2, 5,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc, "R_SPARC_5", false,0,0x0000001f,true), HOWTO(R_SPARC_6, 0,2, 6,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc, "R_SPARC_6", false,0,0x0000003f,true), 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_NONE, 0,0, 0,false,0,complain_overflow_dont, bfd_elf_generic_reloc, "R_SPARC_NONE", false,0,0x00000000,true), 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_NONE, 0,0, 0,false,0,complain_overflow_dont, bfd_elf_generic_reloc, "R_SPARC_NONE", false,0,0x00000000,true), 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_NONE, 0,0, 0,false,0,complain_overflow_dont, bfd_elf_generic_reloc, "R_SPARC_NONE", false,0,0x00000000,true), 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_NONE, 0,0, 0,false,0,complain_overflow_dont, bfd_elf_generic_reloc, "R_SPARC_NONE", false,0,0x00000000,true), HOWTO(R_SPARC_UA64, 0,4,64,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc, "R_SPARC_UA64", false,0,(~ (bfd_vma)0), true), HOWTO(R_SPARC_UA16, 0,1,16,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc, "R_SPARC_UA16", false,0,0x0000ffff,true), HOWTO(R_SPARC_REV32, 0,2,32,false,0,complain_overflow_bitfield,bfd_elf_generic_reloc, "R_SPARC_REV32", false,0,0xffffffff,true),};static reloc_howto_type elf32_sparc_vtinherit_howto = HOWTO (R_SPARC_GNU_VTINHERIT, 0,2,0,false,0,complain_overflow_dont, NULL, "R_SPARC_GNU_VTINHERIT", false,0, 0, false);static reloc_howto_type elf32_sparc_vtentry_howto = HOWTO (R_SPARC_GNU_VTENTRY, 0,2,0,false,0,complain_overflow_dont, _bfd_elf_rel_vtable_reloc_fn,"R_SPARC_GNU_VTENTRY", false,0,0, false);struct elf_reloc_map { bfd_reloc_code_real_type 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 }, { 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_UA16, R_SPARC_UA16 }, { BFD_RELOC_SPARC_UA32, R_SPARC_UA32 }, { BFD_RELOC_SPARC_UA64, R_SPARC_UA64 }, { BFD_RELOC_SPARC_10, R_SPARC_10 }, { BFD_RELOC_SPARC_11, R_SPARC_11 }, { BFD_RELOC_SPARC_64, R_SPARC_64 }, { BFD_RELOC_SPARC_OLO10, R_SPARC_OLO10 }, { BFD_RELOC_SPARC_HH22, R_SPARC_HH22 }, { BFD_RELOC_SPARC_HM10, R_SPARC_HM10 }, { BFD_RELOC_SPARC_LM22, R_SPARC_LM22 }, { BFD_RELOC_SPARC_PC_HH22, R_SPARC_PC_HH22 }, { BFD_RELOC_SPARC_PC_HM10, R_SPARC_PC_HM10 }, { BFD_RELOC_SPARC_PC_LM22, R_SPARC_PC_LM22 }, { BFD_RELOC_SPARC_WDISP16, R_SPARC_WDISP16 }, { BFD_RELOC_SPARC_WDISP19, R_SPARC_WDISP19 }, { BFD_RELOC_SPARC_7, R_SPARC_7 }, { BFD_RELOC_SPARC_5, R_SPARC_5 }, { BFD_RELOC_SPARC_6, R_SPARC_6 }, { BFD_RELOC_SPARC_REV32, R_SPARC_REV32 }, { BFD_RELOC_VTABLE_INHERIT, R_SPARC_GNU_VTINHERIT }, { BFD_RELOC_VTABLE_ENTRY, R_SPARC_GNU_VTENTRY },};static reloc_howto_type *elf32_sparc_reloc_type_lookup (abfd, code) bfd *abfd ATTRIBUTE_UNUSED; bfd_reloc_code_real_type code;{ unsigned int i; switch (code) { case BFD_RELOC_VTABLE_INHERIT: return &elf32_sparc_vtinherit_howto; case BFD_RELOC_VTABLE_ENTRY: return &elf32_sparc_vtentry_howto; default: for (i = 0; i < sizeof (sparc_reloc_map) / sizeof (struct elf_reloc_map); i++) { if (sparc_reloc_map[i].bfd_reloc_val == code) return &_bfd_sparc_elf_howto_table[(int) sparc_reloc_map[i].elf_reloc_val]; } } bfd_set_error (bfd_error_bad_value); return NULL;}/* We need to use ELF32_R_TYPE so we have our own copy of this function, and elf64-sparc.c has its own copy. */static voidelf32_sparc_info_to_howto (abfd, cache_ptr, dst) bfd *abfd ATTRIBUTE_UNUSED; arelent *cache_ptr; Elf_Internal_Rela *dst;{ switch (ELF32_R_TYPE(dst->r_info)) { case R_SPARC_GNU_VTINHERIT: cache_ptr->howto = &elf32_sparc_vtinherit_howto; break; case R_SPARC_GNU_VTENTRY: cache_ptr->howto = &elf32_sparc_vtentry_howto; break; default: BFD_ASSERT (ELF32_R_TYPE(dst->r_info) < (unsigned int) R_SPARC_max_std); cache_ptr->howto = &_bfd_sparc_elf_howto_table[ELF32_R_TYPE(dst->r_info)]; }}/* For unsupported relocs. */static bfd_reloc_status_typesparc_elf_notsupported_reloc (abfd, reloc_entry, symbol, data, input_section, output_bfd, error_message) bfd *abfd ATTRIBUTE_UNUSED; arelent *reloc_entry ATTRIBUTE_UNUSED; asymbol *symbol ATTRIBUTE_UNUSED; PTR data ATTRIBUTE_UNUSED; asection *input_section ATTRIBUTE_UNUSED; bfd *output_bfd ATTRIBUTE_UNUSED; char **error_message ATTRIBUTE_UNUSED;{ return bfd_reloc_notsupported;}/* Handle the WDISP16 reloc. */static bfd_reloc_status_typesparc_elf_wdisp16_reloc (abfd, reloc_entry, symbol, data, input_section, output_bfd, error_message) bfd *abfd; arelent *reloc_entry; asymbol *symbol; PTR data; asection *input_section; bfd *output_bfd; char **error_message ATTRIBUTE_UNUSED;{ bfd_vma relocation; bfd_vma x; if (output_bfd != (bfd *) NULL && (symbol->flags & BSF_SECTION_SYM) == 0 && (! reloc_entry->howto->partial_inplace || reloc_entry->addend == 0)) { reloc_entry->address += input_section->output_offset; return bfd_reloc_ok; } if (output_bfd != NULL) return bfd_reloc_continue; if (reloc_entry->address > input_section->_cooked_size) return bfd_reloc_outofrange; relocation = (symbol->value + symbol->section->output_section->vma + symbol->section->output_offset); relocation += reloc_entry->addend; relocation -= (input_section->output_section->vma + input_section->output_offset); relocation -= reloc_entry->address; x = bfd_get_32 (abfd, (bfd_byte *) data + reloc_entry->address); x |= ((((relocation >> 2) & 0xc000) << 6) | ((relocation >> 2) & 0x3fff)); bfd_put_32 (abfd, x, (bfd_byte *) data + reloc_entry->address); if ((bfd_signed_vma) relocation < - 0x40000 || (bfd_signed_vma) relocation > 0x3ffff) return bfd_reloc_overflow; else return bfd_reloc_ok;}/* 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/* Look through the relocs for a section during the first phase, and allocate space in the global offset table or procedure linkage table. */static booleanelf32_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++) { unsigned 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 (! _bfd_elf_create_got_section (dynobj, info)) return false; } if (sgot == NULL) { sgot = bfd_get_section_by_name (dynobj, ".got"); BFD_ASSERT (sgot != NULL);
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