1 /* ARC-specific support for 32-bit ELF
2 Copyright (C) 1994-2014 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 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 "elf-bfd.h"
26 #include "elf/arc.h"
27 #include "libiberty.h"
28
29 /* Try to minimize the amount of space occupied by relocation tables
30 on the ROM (not that the ROM won't be swamped by other ELF overhead). */
31
32 #define USE_REL 1
33
34 static bfd_reloc_status_type
arc_elf_b22_pcrel(bfd * abfd,arelent * reloc_entry,asymbol * symbol,void * data,asection * input_section,bfd * output_bfd,char ** error_message)35 arc_elf_b22_pcrel (bfd * abfd,
36 arelent * reloc_entry,
37 asymbol * symbol,
38 void * data,
39 asection * input_section,
40 bfd * output_bfd,
41 char ** error_message)
42 {
43 /* If linking, back up the final symbol address by the address of the
44 reloc. This cannot be accomplished by setting the pcrel_offset
45 field to TRUE, as bfd_install_relocation will detect this and refuse
46 to install the offset in the first place, but bfd_perform_relocation
47 will still insist on removing it. */
48 if (output_bfd == NULL)
49 reloc_entry->addend -= reloc_entry->address;
50
51 /* Fall through to the default elf reloc handler. */
52 return bfd_elf_generic_reloc (abfd, reloc_entry, symbol, data,
53 input_section, output_bfd, error_message);
54 }
55
56 static reloc_howto_type elf_arc_howto_table[] =
57 {
58 /* This reloc does nothing. */
59 HOWTO (R_ARC_NONE, /* 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_NONE", /* Name. */
68 TRUE, /* Partial_inplace. */
69 0, /* Src_mask. */
70 0, /* Dst_mask. */
71 FALSE), /* PCrel_offset. */
72
73 /* A standard 32 bit relocation. */
74 HOWTO (R_ARC_32, /* Type. */
75 0, /* Rightshift. */
76 2, /* Size (0 = byte, 1 = short, 2 = long). */
77 32, /* 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_32", /* Name. */
83 TRUE, /* Partial_inplace. */
84 0xffffffff, /* Src_mask. */
85 0xffffffff, /* Dst_mask. */
86 FALSE), /* PCrel_offset. */
87
88 /* A 26 bit absolute branch, right shifted by 2. */
89 HOWTO (R_ARC_B26, /* Type. */
90 2, /* Rightshift. */
91 2, /* Size (0 = byte, 1 = short, 2 = long). */
92 26, /* Bitsize. */
93 FALSE, /* PC_relative. */
94 0, /* Bitpos. */
95 complain_overflow_bitfield, /* Complain_on_overflow. */
96 bfd_elf_generic_reloc, /* Special_function. */
97 "R_ARC_B26", /* Name. */
98 TRUE, /* Partial_inplace. */
99 0x00ffffff, /* Src_mask. */
100 0x00ffffff, /* Dst_mask. */
101 FALSE), /* PCrel_offset. */
102
103 /* A relative 22 bit branch; bits 21-2 are stored in bits 26-7. */
104 HOWTO (R_ARC_B22_PCREL, /* Type. */
105 2, /* Rightshift. */
106 2, /* Size (0 = byte, 1 = short, 2 = long). */
107 22, /* Bitsize. */
108 TRUE, /* PC_relative. */
109 7, /* Bitpos. */
110 complain_overflow_signed, /* Complain_on_overflow. */
111 arc_elf_b22_pcrel, /* Special_function. */
112 "R_ARC_B22_PCREL", /* Name. */
113 TRUE, /* Partial_inplace. */
114 0x07ffff80, /* Src_mask. */
115 0x07ffff80, /* Dst_mask. */
116 FALSE), /* PCrel_offset. */
117 };
118
119 /* Map BFD reloc types to ARC ELF reloc types. */
120
121 struct arc_reloc_map
122 {
123 bfd_reloc_code_real_type bfd_reloc_val;
124 unsigned char elf_reloc_val;
125 };
126
127 static const struct arc_reloc_map arc_reloc_map[] =
128 {
129 { BFD_RELOC_NONE, R_ARC_NONE, },
130 { BFD_RELOC_32, R_ARC_32 },
131 { BFD_RELOC_CTOR, R_ARC_32 },
132 { BFD_RELOC_ARC_B26, R_ARC_B26 },
133 { BFD_RELOC_ARC_B22_PCREL, R_ARC_B22_PCREL },
134 };
135
136 static reloc_howto_type *
bfd_elf32_bfd_reloc_type_lookup(bfd * abfd ATTRIBUTE_UNUSED,bfd_reloc_code_real_type code)137 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
138 bfd_reloc_code_real_type code)
139 {
140 unsigned int i;
141
142 for (i = ARRAY_SIZE (arc_reloc_map); i--;)
143 if (arc_reloc_map[i].bfd_reloc_val == code)
144 return elf_arc_howto_table + arc_reloc_map[i].elf_reloc_val;
145
146 return NULL;
147 }
148
149 static reloc_howto_type *
bfd_elf32_bfd_reloc_name_lookup(bfd * abfd ATTRIBUTE_UNUSED,const char * r_name)150 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
151 const char *r_name)
152 {
153 unsigned int i;
154
155 for (i = 0;
156 i < sizeof (elf_arc_howto_table) / sizeof (elf_arc_howto_table[0]);
157 i++)
158 if (elf_arc_howto_table[i].name != NULL
159 && strcasecmp (elf_arc_howto_table[i].name, r_name) == 0)
160 return &elf_arc_howto_table[i];
161
162 return NULL;
163 }
164
165 /* Set the howto pointer for an ARC ELF reloc. */
166
167 static void
arc_info_to_howto_rel(bfd * abfd ATTRIBUTE_UNUSED,arelent * cache_ptr,Elf_Internal_Rela * dst)168 arc_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED,
169 arelent *cache_ptr,
170 Elf_Internal_Rela *dst)
171 {
172 unsigned int r_type;
173
174 r_type = ELF32_R_TYPE (dst->r_info);
175 BFD_ASSERT (r_type < (unsigned int) R_ARC_max);
176 cache_ptr->howto = &elf_arc_howto_table[r_type];
177 }
178
179 /* Set the right machine number for an ARC ELF file. */
180
181 static bfd_boolean
arc_elf_object_p(bfd * abfd)182 arc_elf_object_p (bfd *abfd)
183 {
184 unsigned int mach = bfd_mach_arc_6;
185
186 if (elf_elfheader(abfd)->e_machine == EM_ARC)
187 {
188 unsigned long arch = elf_elfheader (abfd)->e_flags & EF_ARC_MACH;
189
190 switch (arch)
191 {
192 case E_ARC_MACH_ARC5:
193 mach = bfd_mach_arc_5;
194 break;
195 default:
196 case E_ARC_MACH_ARC6:
197 mach = bfd_mach_arc_6;
198 break;
199 case E_ARC_MACH_ARC7:
200 mach = bfd_mach_arc_7;
201 break;
202 case E_ARC_MACH_ARC8:
203 mach = bfd_mach_arc_8;
204 break;
205 }
206 }
207 return bfd_default_set_arch_mach (abfd, bfd_arch_arc, mach);
208 }
209
210 /* The final processing done just before writing out an ARC ELF object file.
211 This gets the ARC architecture right based on the machine number. */
212
213 static void
arc_elf_final_write_processing(bfd * abfd,bfd_boolean linker ATTRIBUTE_UNUSED)214 arc_elf_final_write_processing (bfd *abfd,
215 bfd_boolean linker ATTRIBUTE_UNUSED)
216 {
217 unsigned long val;
218
219 switch (bfd_get_mach (abfd))
220 {
221 case bfd_mach_arc_5:
222 val = E_ARC_MACH_ARC5;
223 break;
224 default:
225 case bfd_mach_arc_6:
226 val = E_ARC_MACH_ARC6;
227 break;
228 case bfd_mach_arc_7:
229 val = E_ARC_MACH_ARC7;
230 break;
231 case bfd_mach_arc_8:
232 val = E_ARC_MACH_ARC8;
233 break;
234 }
235 elf_elfheader (abfd)->e_flags &=~ EF_ARC_MACH;
236 elf_elfheader (abfd)->e_flags |= val;
237 }
238
239 #define TARGET_LITTLE_SYM arc_elf32_le_vec
240 #define TARGET_LITTLE_NAME "elf32-littlearc"
241 #define TARGET_BIG_SYM arc_elf32_be_vec
242 #define TARGET_BIG_NAME "elf32-bigarc"
243 #define ELF_ARCH bfd_arch_arc
244 #define ELF_MACHINE_CODE EM_ARC
245 #define ELF_MAXPAGESIZE 0x1000
246
247 #define elf_info_to_howto 0
248 #define elf_info_to_howto_rel arc_info_to_howto_rel
249 #define elf_backend_object_p arc_elf_object_p
250 #define elf_backend_final_write_processing arc_elf_final_write_processing
251
252 #include "elf32-target.h"
253