elf32-arc.c revision 85815 
1/* ARC-specific support for 32-bit ELF
2   Copyright 1994, 1995, 1997, 1999, 2001 Free Software Foundation, Inc.
3   Contributed by Doug Evans (dje@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 2 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
20
21#include "bfd.h"
22#include "sysdep.h"
23#include "libbfd.h"
24#include "elf-bfd.h"
25#include "elf/arc.h"
26
27static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
28  PARAMS ((bfd *abfd, bfd_reloc_code_real_type code));
29static void arc_info_to_howto_rel
30  PARAMS ((bfd *, arelent *, Elf32_Internal_Rel *));
31static boolean arc_elf_object_p
32  PARAMS ((bfd *));
33static void arc_elf_final_write_processing
34  PARAMS ((bfd *, boolean));
35
36/* Try to minimize the amount of space occupied by relocation tables
37   on the ROM (not that the ROM won't be swamped by other ELF overhead).  */
38
39#define USE_REL
40
41static reloc_howto_type elf_arc_howto_table[] =
42{
43  /* This reloc does nothing.  */
44  HOWTO (R_ARC_NONE,		/* type  */
45	 0,			/* rightshift  */
46	 2,			/* size (0 = byte, 1 = short, 2 = long)  */
47	 32,			/* bitsize  */
48	 false,			/* pc_relative  */
49	 0,			/* bitpos  */
50	 complain_overflow_bitfield, /* complain_on_overflow  */
51	 bfd_elf_generic_reloc,	/* special_function  */
52	 "R_ARC_NONE",		/* name  */
53	 false,			/* partial_inplace  */
54	 0,			/* src_mask  */
55	 0,			/* dst_mask  */
56	 false),		/* pcrel_offset  */
57
58  /* A standard 32 bit relocation.  */
59  HOWTO (R_ARC_32,		/* type  */
60	 0,			/* rightshift  */
61	 2,			/* size (0 = byte, 1 = short, 2 = long)  */
62	 32,			/* bitsize  */
63	 false,			/* pc_relative  */
64	 0,			/* bitpos  */
65	 complain_overflow_bitfield, /* complain_on_overflow  */
66	 bfd_elf_generic_reloc,	/* special_function  */
67	 "R_ARC_32",		/* name  */
68	 false,			/* partial_inplace  */
69	 0xffffffff,		/* src_mask  */
70	 0xffffffff,		/* dst_mask  */
71	 false),		/* pcrel_offset  */
72
73  /* A 26 bit absolute branch, right shifted by 2.  */
74  HOWTO (R_ARC_B26,		/* type  */
75	 2,			/* rightshift  */
76	 2,			/* size (0 = byte, 1 = short, 2 = long)  */
77	 26,			/* bitsize  */
78	 false,			/* pc_relative  */
79	 0,			/* bitpos  */
80	 complain_overflow_bitfield, /* complain_on_overflow  */
81	 bfd_elf_generic_reloc,	/* special_function  */
82	 "R_ARC_B26",		/* name  */
83	 false,			/* partial_inplace  */
84	 0x00ffffff,		/* src_mask  */
85	 0x00ffffff,		/* dst_mask  */
86	 false),		/* pcrel_offset  */
87
88  /* A relative 22 bit branch; bits 21-2 are stored in bits 26-7.  */
89  HOWTO (R_ARC_B22_PCREL,	/* type  */
90	 2,			/* rightshift  */
91	 2,			/* size (0 = byte, 1 = short, 2 = long)  */
92	 22,			/* bitsize  */
93	 true,			/* pc_relative  */
94	 7,			/* bitpos  */
95	 complain_overflow_signed, /* complain_on_overflow  */
96	 bfd_elf_generic_reloc,	/* special_function  */
97	 "R_ARC_B22_PCREL",	/* name  */
98	 false,			/* partial_inplace  */
99	 0x07ffff80,		/* src_mask  */
100	 0x07ffff80,		/* dst_mask  */
101	 true),			/* pcrel_offset  */
102
103};
104
105/* Map BFD reloc types to ARC ELF reloc types.  */
106
107struct arc_reloc_map
108{
109  bfd_reloc_code_real_type bfd_reloc_val;
110  unsigned char elf_reloc_val;
111};
112
113static const struct arc_reloc_map arc_reloc_map[] =
114{
115  { BFD_RELOC_NONE, R_ARC_NONE, },
116  { BFD_RELOC_32, R_ARC_32 },
117  { BFD_RELOC_CTOR, R_ARC_32 },
118  { BFD_RELOC_ARC_B26, R_ARC_B26 },
119  { BFD_RELOC_ARC_B22_PCREL, R_ARC_B22_PCREL },
120};
121
122static reloc_howto_type *
123bfd_elf32_bfd_reloc_type_lookup (abfd, code)
124     bfd *abfd ATTRIBUTE_UNUSED;
125     bfd_reloc_code_real_type code;
126{
127  unsigned int i;
128
129  for (i = 0; i < sizeof (arc_reloc_map) / sizeof (struct arc_reloc_map); i++)
130    {
131      if (arc_reloc_map[i].bfd_reloc_val == code)
132	return &elf_arc_howto_table[arc_reloc_map[i].elf_reloc_val];
133    }
134  return NULL;
135}
136
137/* Set the howto pointer for an ARC ELF reloc.  */
138
139static void
140arc_info_to_howto_rel (abfd, cache_ptr, dst)
141     bfd *abfd ATTRIBUTE_UNUSED;
142     arelent *cache_ptr;
143     Elf32_Internal_Rel *dst;
144{
145  unsigned int r_type;
146
147  r_type = ELF32_R_TYPE (dst->r_info);
148  BFD_ASSERT (r_type < (unsigned int) R_ARC_max);
149  cache_ptr->howto = &elf_arc_howto_table[r_type];
150}
151
152/* Set the right machine number for an ARC ELF file.  */
153
154static boolean
155arc_elf_object_p (abfd)
156     bfd *abfd;
157{
158  int mach = bfd_mach_arc_6;
159
160  if (elf_elfheader(abfd)->e_machine == EM_ARC)
161    {
162      unsigned long arch = elf_elfheader (abfd)->e_flags & EF_ARC_MACH;
163
164      switch (arch)
165	{
166	case E_ARC_MACH_ARC5:
167	  mach = bfd_mach_arc_5;
168	  break;
169	default:
170	case E_ARC_MACH_ARC6:
171	  mach = bfd_mach_arc_6;
172	  break;
173	case E_ARC_MACH_ARC7:
174	  mach = bfd_mach_arc_7;
175	  break;
176	case E_ARC_MACH_ARC8:
177	  mach = bfd_mach_arc_8;
178	  break;
179	}
180    }
181  return bfd_default_set_arch_mach (abfd, bfd_arch_arc, mach);
182}
183
184/* The final processing done just before writing out an ARC ELF object file.
185   This gets the ARC architecture right based on the machine number.  */
186
187static void
188arc_elf_final_write_processing (abfd, linker)
189     bfd *abfd;
190     boolean linker ATTRIBUTE_UNUSED;
191{
192  unsigned long val;
193
194  switch (bfd_get_mach (abfd))
195    {
196    case bfd_mach_arc_5:
197      val = E_ARC_MACH_ARC5;
198      break;
199    default:
200    case bfd_mach_arc_6:
201      val = E_ARC_MACH_ARC6;
202      break;
203    case bfd_mach_arc_7:
204      val = E_ARC_MACH_ARC7;
205      break;
206    case bfd_mach_arc_8:
207      val = E_ARC_MACH_ARC8;
208      break;
209    }
210  elf_elfheader (abfd)->e_machine = EM_ARC;
211  elf_elfheader (abfd)->e_flags &=~ EF_ARC_MACH;
212  elf_elfheader (abfd)->e_flags |= val;
213}
214
215#define TARGET_LITTLE_SYM bfd_elf32_littlearc_vec
216#define TARGET_LITTLE_NAME "elf32-littlearc"
217#define TARGET_BIG_SYM bfd_elf32_bigarc_vec
218#define TARGET_BIG_NAME	"elf32-bigarc"
219#define ELF_ARCH bfd_arch_arc
220#define ELF_MACHINE_CODE EM_ARC
221#define ELF_MAXPAGESIZE	0x1000
222
223#define elf_info_to_howto 0
224#define elf_info_to_howto_rel arc_info_to_howto_rel
225#define elf_backend_object_p arc_elf_object_p
226#define elf_backend_final_write_processing arc_elf_final_write_processing
227
228#include "elf32-target.h"
229