cpu-ns32k.c revision 1.1.1.8.2.1 1 1.1 skrll /* BFD support for the ns32k architecture.
2 1.1.1.8.2.1 perseant Copyright (C) 1990-2024 Free Software Foundation, Inc.
3 1.1 skrll Almost totally rewritten by Ian Dall from initial work
4 1.1 skrll by Andrew Cagney.
5 1.1 skrll
6 1.1 skrll This file is part of BFD, the Binary File Descriptor library.
7 1.1 skrll
8 1.1 skrll This program is free software; you can redistribute it and/or modify
9 1.1 skrll it under the terms of the GNU General Public License as published by
10 1.1 skrll the Free Software Foundation; either version 3 of the License, or
11 1.1 skrll (at your option) any later version.
12 1.1 skrll
13 1.1 skrll This program is distributed in the hope that it will be useful,
14 1.1 skrll but WITHOUT ANY WARRANTY; without even the implied warranty of
15 1.1 skrll MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 1.1 skrll GNU General Public License for more details.
17 1.1 skrll
18 1.1 skrll You should have received a copy of the GNU General Public License
19 1.1 skrll along with this program; if not, write to the Free Software
20 1.1 skrll Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 1.1 skrll MA 02110-1301, USA. */
22 1.1 skrll
23 1.1 skrll #include "sysdep.h"
24 1.1 skrll #include "bfd.h"
25 1.1 skrll #include "libbfd.h"
26 1.1 skrll #include "ns32k.h"
27 1.1 skrll
28 1.1 skrll #define N(machine, printable, d, next) \
29 1.1.1.7 christos { 32, 32, 8, bfd_arch_ns32k, machine, "ns32k",printable,3,d, \
30 1.1.1.7 christos bfd_default_compatible,bfd_default_scan,bfd_arch_default_fill,next, 0 }
31 1.1 skrll
32 1.1 skrll static const bfd_arch_info_type arch_info_struct[] =
33 1.1 skrll {
34 1.1.1.8 christos N (32532, "ns32k:32532", true, 0), /* The word ns32k will match this too. */
35 1.1 skrll };
36 1.1 skrll
37 1.1 skrll const bfd_arch_info_type bfd_ns32k_arch =
38 1.1.1.8 christos N (32032, "ns32k:32032", false, &arch_info_struct[0]);
39 1.1 skrll
40 1.1 skrll bfd_vma
41 1.1.1.2 christos _bfd_ns32k_get_displacement (bfd_byte *buffer, int size)
42 1.1 skrll {
43 1.1 skrll bfd_signed_vma value;
44 1.1 skrll
45 1.1 skrll switch (size)
46 1.1 skrll {
47 1.1 skrll case 1:
48 1.1 skrll value = ((*buffer & 0x7f) ^ 0x40) - 0x40;
49 1.1 skrll break;
50 1.1 skrll
51 1.1 skrll case 2:
52 1.1 skrll value = ((*buffer++ & 0x3f) ^ 0x20) - 0x20;
53 1.1 skrll value = (value << 8) | (0xff & *buffer);
54 1.1 skrll break;
55 1.1 skrll
56 1.1 skrll case 4:
57 1.1 skrll value = ((*buffer++ & 0x3f) ^ 0x20) - 0x20;
58 1.1 skrll value = (value << 8) | (0xff & *buffer++);
59 1.1 skrll value = (value << 8) | (0xff & *buffer++);
60 1.1 skrll value = (value << 8) | (0xff & *buffer);
61 1.1 skrll break;
62 1.1 skrll
63 1.1 skrll default:
64 1.1 skrll abort ();
65 1.1 skrll return 0;
66 1.1 skrll }
67 1.1 skrll
68 1.1 skrll return value;
69 1.1 skrll }
70 1.1 skrll
71 1.1 skrll void
72 1.1.1.2 christos _bfd_ns32k_put_displacement (bfd_vma value, bfd_byte *buffer, int size)
73 1.1 skrll {
74 1.1 skrll switch (size)
75 1.1 skrll {
76 1.1 skrll case 1:
77 1.1 skrll value &= 0x7f;
78 1.1 skrll *buffer++ = value;
79 1.1 skrll break;
80 1.1 skrll
81 1.1 skrll case 2:
82 1.1 skrll value &= 0x3fff;
83 1.1 skrll value |= 0x8000;
84 1.1 skrll *buffer++ = (value >> 8);
85 1.1 skrll *buffer++ = value;
86 1.1 skrll break;
87 1.1 skrll
88 1.1 skrll case 4:
89 1.1 skrll value |= (bfd_vma) 0xc0000000;
90 1.1 skrll *buffer++ = (value >> 24);
91 1.1 skrll *buffer++ = (value >> 16);
92 1.1 skrll *buffer++ = (value >> 8);
93 1.1 skrll *buffer++ = value;
94 1.1 skrll break;
95 1.1 skrll }
96 1.1 skrll return;
97 1.1 skrll }
98 1.1 skrll
99 1.1 skrll bfd_vma
100 1.1.1.2 christos _bfd_ns32k_get_immediate (bfd_byte *buffer, int size)
101 1.1 skrll {
102 1.1 skrll bfd_vma value = 0;
103 1.1 skrll
104 1.1 skrll switch (size)
105 1.1 skrll {
106 1.1 skrll case 4:
107 1.1 skrll value = (value << 8) | (*buffer++ & 0xff);
108 1.1 skrll value = (value << 8) | (*buffer++ & 0xff);
109 1.1.1.5 christos /* Fall through. */
110 1.1 skrll case 2:
111 1.1 skrll value = (value << 8) | (*buffer++ & 0xff);
112 1.1.1.5 christos /* Fall through. */
113 1.1 skrll case 1:
114 1.1 skrll value = (value << 8) | (*buffer++ & 0xff);
115 1.1 skrll break;
116 1.1 skrll default:
117 1.1 skrll abort ();
118 1.1 skrll }
119 1.1 skrll return value;
120 1.1 skrll }
121 1.1 skrll
122 1.1 skrll void
123 1.1.1.2 christos _bfd_ns32k_put_immediate (bfd_vma value, bfd_byte *buffer, int size)
124 1.1 skrll {
125 1.1 skrll buffer += size - 1;
126 1.1 skrll switch (size)
127 1.1 skrll {
128 1.1 skrll case 4:
129 1.1 skrll *buffer-- = (value & 0xff); value >>= 8;
130 1.1 skrll *buffer-- = (value & 0xff); value >>= 8;
131 1.1.1.5 christos /* Fall through. */
132 1.1 skrll case 2:
133 1.1 skrll *buffer-- = (value & 0xff); value >>= 8;
134 1.1.1.5 christos /* Fall through. */
135 1.1 skrll case 1:
136 1.1 skrll *buffer-- = (value & 0xff); value >>= 8;
137 1.1 skrll }
138 1.1 skrll }
139 1.1 skrll
140 1.1 skrll /* This is just like the standard perform_relocation except we
141 1.1 skrll use get_data and put_data which know about the ns32k storage
142 1.1 skrll methods. This is probably a lot more complicated than it
143 1.1 skrll needs to be! */
144 1.1 skrll
145 1.1 skrll static bfd_reloc_status_type
146 1.1.1.2 christos do_ns32k_reloc (bfd * abfd,
147 1.1.1.2 christos arelent * reloc_entry,
148 1.1.1.2 christos struct bfd_symbol * symbol,
149 1.1.1.2 christos void * data,
150 1.1.1.2 christos asection * input_section,
151 1.1.1.2 christos bfd * output_bfd,
152 1.1.1.2 christos char ** error_message ATTRIBUTE_UNUSED,
153 1.1.1.2 christos bfd_vma (* get_data) (bfd_byte *, int),
154 1.1.1.2 christos void (* put_data) (bfd_vma, bfd_byte *, int))
155 1.1 skrll {
156 1.1 skrll int overflow = 0;
157 1.1 skrll bfd_vma relocation;
158 1.1 skrll bfd_reloc_status_type flag = bfd_reloc_ok;
159 1.1 skrll bfd_size_type addr = reloc_entry->address;
160 1.1 skrll bfd_vma output_base = 0;
161 1.1 skrll reloc_howto_type *howto = reloc_entry->howto;
162 1.1 skrll asection *reloc_target_output_section;
163 1.1 skrll bfd_byte *location;
164 1.1 skrll
165 1.1.1.2 christos if (bfd_is_abs_section (symbol->section)
166 1.1 skrll && output_bfd != (bfd *) NULL)
167 1.1 skrll {
168 1.1 skrll reloc_entry->address += input_section->output_offset;
169 1.1 skrll return bfd_reloc_ok;
170 1.1 skrll }
171 1.1 skrll
172 1.1 skrll /* If we are not producing relocatable output, return an error if
173 1.1 skrll the symbol is not defined. An undefined weak symbol is
174 1.1 skrll considered to have a value of zero (SVR4 ABI, p. 4-27). */
175 1.1.1.2 christos if (bfd_is_und_section (symbol->section)
176 1.1 skrll && (symbol->flags & BSF_WEAK) == 0
177 1.1 skrll && output_bfd == (bfd *) NULL)
178 1.1 skrll flag = bfd_reloc_undefined;
179 1.1 skrll
180 1.1 skrll /* Is the address of the relocation really within the section? */
181 1.1 skrll if (reloc_entry->address > bfd_get_section_limit (abfd, input_section))
182 1.1 skrll return bfd_reloc_outofrange;
183 1.1 skrll
184 1.1 skrll /* Work out which section the relocation is targeted at and the
185 1.1 skrll initial relocation command value. */
186 1.1 skrll
187 1.1 skrll /* Get symbol value. (Common symbols are special.) */
188 1.1 skrll if (bfd_is_com_section (symbol->section))
189 1.1 skrll relocation = 0;
190 1.1 skrll else
191 1.1 skrll relocation = symbol->value;
192 1.1 skrll
193 1.1 skrll reloc_target_output_section = symbol->section->output_section;
194 1.1 skrll
195 1.1 skrll /* Convert input-section-relative symbol value to absolute. */
196 1.1 skrll if (output_bfd != NULL && ! howto->partial_inplace)
197 1.1 skrll output_base = 0;
198 1.1 skrll else
199 1.1 skrll output_base = reloc_target_output_section->vma;
200 1.1 skrll
201 1.1 skrll relocation += output_base + symbol->section->output_offset;
202 1.1 skrll
203 1.1 skrll /* Add in supplied addend. */
204 1.1 skrll relocation += reloc_entry->addend;
205 1.1 skrll
206 1.1 skrll /* Here the variable relocation holds the final address of the
207 1.1 skrll symbol we are relocating against, plus any addend. */
208 1.1 skrll
209 1.1 skrll if (howto->pc_relative)
210 1.1 skrll {
211 1.1 skrll /* This is a PC relative relocation. We want to set RELOCATION
212 1.1 skrll to the distance between the address of the symbol and the
213 1.1 skrll location. RELOCATION is already the address of the symbol.
214 1.1 skrll
215 1.1 skrll We start by subtracting the address of the section containing
216 1.1 skrll the location.
217 1.1 skrll
218 1.1 skrll If pcrel_offset is set, we must further subtract the position
219 1.1 skrll of the location within the section. Some targets arrange for
220 1.1 skrll the addend to be the negative of the position of the location
221 1.1 skrll within the section; for example, i386-aout does this. For
222 1.1 skrll i386-aout, pcrel_offset is FALSE. Some other targets do not
223 1.1.1.6 christos include the position of the location; for example, ELF.
224 1.1.1.6 christos For those targets, pcrel_offset is TRUE.
225 1.1 skrll
226 1.1 skrll If we are producing relocatable output, then we must ensure
227 1.1 skrll that this reloc will be correctly computed when the final
228 1.1 skrll relocation is done. If pcrel_offset is FALSE we want to wind
229 1.1 skrll up with the negative of the location within the section,
230 1.1 skrll which means we must adjust the existing addend by the change
231 1.1 skrll in the location within the section. If pcrel_offset is TRUE
232 1.1 skrll we do not want to adjust the existing addend at all.
233 1.1 skrll
234 1.1 skrll FIXME: This seems logical to me, but for the case of
235 1.1 skrll producing relocatable output it is not what the code
236 1.1 skrll actually does. I don't want to change it, because it seems
237 1.1 skrll far too likely that something will break. */
238 1.1 skrll relocation -=
239 1.1 skrll input_section->output_section->vma + input_section->output_offset;
240 1.1 skrll
241 1.1 skrll if (howto->pcrel_offset)
242 1.1 skrll relocation -= reloc_entry->address;
243 1.1 skrll }
244 1.1 skrll
245 1.1 skrll if (output_bfd != (bfd *) NULL)
246 1.1 skrll {
247 1.1 skrll if (! howto->partial_inplace)
248 1.1 skrll {
249 1.1 skrll /* This is a partial relocation, and we want to apply the relocation
250 1.1 skrll to the reloc entry rather than the raw data. Modify the reloc
251 1.1 skrll inplace to reflect what we now know. */
252 1.1 skrll reloc_entry->addend = relocation;
253 1.1 skrll reloc_entry->address += input_section->output_offset;
254 1.1 skrll return flag;
255 1.1 skrll }
256 1.1 skrll else
257 1.1 skrll {
258 1.1 skrll /* This is a partial relocation, but inplace, so modify the
259 1.1 skrll reloc record a bit.
260 1.1 skrll
261 1.1 skrll If we've relocated with a symbol with a section, change
262 1.1 skrll into a ref to the section belonging to the symbol. */
263 1.1 skrll
264 1.1 skrll reloc_entry->address += input_section->output_offset;
265 1.1 skrll
266 1.1 skrll /* WTF?? */
267 1.1 skrll if (abfd->xvec->flavour == bfd_target_coff_flavour)
268 1.1 skrll {
269 1.1 skrll /* For m68k-coff, the addend was being subtracted twice during
270 1.1 skrll relocation with -r. Removing the line below this comment
271 1.1 skrll fixes that problem; see PR 2953.
272 1.1 skrll
273 1.1 skrll However, Ian wrote the following, regarding removing the line
274 1.1 skrll below, which explains why it is still enabled: --djm
275 1.1 skrll
276 1.1 skrll If you put a patch like that into BFD you need to check all
277 1.1 skrll the COFF linkers. I am fairly certain that patch will break
278 1.1 skrll coff-i386 (e.g., SCO); see coff_i386_reloc in coff-i386.c
279 1.1 skrll where I worked around the problem in a different way. There
280 1.1 skrll may very well be a reason that the code works as it does.
281 1.1 skrll
282 1.1 skrll Hmmm. The first obvious point is that bfd_perform_relocation
283 1.1 skrll should not have any tests that depend upon the flavour. It's
284 1.1 skrll seem like entirely the wrong place for such a thing. The
285 1.1 skrll second obvious point is that the current code ignores the
286 1.1 skrll reloc addend when producing relocatable output for COFF.
287 1.1 skrll That's peculiar. In fact, I really have no idea what the
288 1.1 skrll point of the line you want to remove is.
289 1.1 skrll
290 1.1 skrll A typical COFF reloc subtracts the old value of the symbol
291 1.1 skrll and adds in the new value to the location in the object file
292 1.1 skrll (if it's a pc relative reloc it adds the difference between
293 1.1 skrll the symbol value and the location). When relocating we need
294 1.1 skrll to preserve that property.
295 1.1 skrll
296 1.1 skrll BFD handles this by setting the addend to the negative of the
297 1.1 skrll old value of the symbol. Unfortunately it handles common
298 1.1 skrll symbols in a non-standard way (it doesn't subtract the old
299 1.1 skrll value) but that's a different story (we can't change it
300 1.1 skrll without losing backward compatibility with old object files)
301 1.1 skrll (coff-i386 does subtract the old value, to be compatible with
302 1.1 skrll existing coff-i386 targets, like SCO).
303 1.1 skrll
304 1.1 skrll So everything works fine when not producing relocatable
305 1.1 skrll output. When we are producing relocatable output, logically
306 1.1 skrll we should do exactly what we do when not producing
307 1.1 skrll relocatable output. Therefore, your patch is correct. In
308 1.1 skrll fact, it should probably always just set reloc_entry->addend
309 1.1 skrll to 0 for all cases, since it is, in fact, going to add the
310 1.1 skrll value into the object file. This won't hurt the COFF code,
311 1.1 skrll which doesn't use the addend; I'm not sure what it will do
312 1.1 skrll to other formats (the thing to check for would be whether
313 1.1 skrll any formats both use the addend and set partial_inplace).
314 1.1 skrll
315 1.1 skrll When I wanted to make coff-i386 produce relocatable output,
316 1.1 skrll I ran into the problem that you are running into: I wanted
317 1.1 skrll to remove that line. Rather than risk it, I made the
318 1.1 skrll coff-i386 relocs use a special function; it's coff_i386_reloc
319 1.1 skrll in coff-i386.c. The function specifically adds the addend
320 1.1 skrll field into the object file, knowing that bfd_perform_relocation
321 1.1 skrll is not going to. If you remove that line, then coff-i386.c
322 1.1 skrll will wind up adding the addend field in twice. It's trivial
323 1.1 skrll to fix; it just needs to be done.
324 1.1 skrll
325 1.1 skrll The problem with removing the line is just that it may break
326 1.1 skrll some working code. With BFD it's hard to be sure of anything.
327 1.1 skrll The right way to deal with this is simply to build and test at
328 1.1 skrll least all the supported COFF targets. It should be
329 1.1 skrll straightforward if time and disk space consuming. For each
330 1.1 skrll target:
331 1.1 skrll 1) build the linker
332 1.1 skrll 2) generate some executable, and link it using -r (I would
333 1.1 skrll probably use paranoia.o and link against newlib/libc.a,
334 1.1 skrll which for all the supported targets would be available in
335 1.1 skrll /usr/cygnus/progressive/H-host/target/lib/libc.a).
336 1.1 skrll 3) make the change to reloc.c
337 1.1 skrll 4) rebuild the linker
338 1.1 skrll 5) repeat step 2
339 1.1 skrll 6) if the resulting object files are the same, you have at
340 1.1 skrll least made it no worse
341 1.1 skrll 7) if they are different you have to figure out which
342 1.1 skrll version is right. */
343 1.1 skrll relocation -= reloc_entry->addend;
344 1.1 skrll reloc_entry->addend = 0;
345 1.1 skrll }
346 1.1 skrll else
347 1.1 skrll {
348 1.1 skrll reloc_entry->addend = relocation;
349 1.1 skrll }
350 1.1 skrll }
351 1.1 skrll }
352 1.1 skrll else
353 1.1 skrll {
354 1.1 skrll reloc_entry->addend = 0;
355 1.1 skrll }
356 1.1 skrll
357 1.1 skrll /* FIXME: This overflow checking is incomplete, because the value
358 1.1 skrll might have overflowed before we get here. For a correct check we
359 1.1 skrll need to compute the value in a size larger than bitsize, but we
360 1.1 skrll can't reasonably do that for a reloc the same size as a host
361 1.1 skrll machine word.
362 1.1 skrll FIXME: We should also do overflow checking on the result after
363 1.1 skrll adding in the value contained in the object file. */
364 1.1 skrll if (howto->complain_on_overflow != complain_overflow_dont)
365 1.1 skrll {
366 1.1 skrll bfd_vma check;
367 1.1 skrll
368 1.1 skrll /* Get the value that will be used for the relocation, but
369 1.1 skrll starting at bit position zero. */
370 1.1 skrll if (howto->rightshift > howto->bitpos)
371 1.1 skrll check = relocation >> (howto->rightshift - howto->bitpos);
372 1.1 skrll else
373 1.1 skrll check = relocation << (howto->bitpos - howto->rightshift);
374 1.1 skrll switch (howto->complain_on_overflow)
375 1.1 skrll {
376 1.1 skrll case complain_overflow_signed:
377 1.1 skrll {
378 1.1 skrll /* Assumes two's complement. */
379 1.1 skrll bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
380 1.1 skrll bfd_signed_vma reloc_signed_min = ~reloc_signed_max;
381 1.1 skrll
382 1.1 skrll /* The above right shift is incorrect for a signed value.
383 1.1 skrll Fix it up by forcing on the upper bits. */
384 1.1 skrll if (howto->rightshift > howto->bitpos
385 1.1 skrll && (bfd_signed_vma) relocation < 0)
386 1.1 skrll check |= ((bfd_vma) - 1
387 1.1 skrll & ~((bfd_vma) - 1
388 1.1 skrll >> (howto->rightshift - howto->bitpos)));
389 1.1 skrll if ((bfd_signed_vma) check > reloc_signed_max
390 1.1 skrll || (bfd_signed_vma) check < reloc_signed_min)
391 1.1 skrll flag = bfd_reloc_overflow;
392 1.1 skrll }
393 1.1 skrll break;
394 1.1 skrll case complain_overflow_unsigned:
395 1.1 skrll {
396 1.1 skrll /* Assumes two's complement. This expression avoids
397 1.1 skrll overflow if howto->bitsize is the number of bits in
398 1.1 skrll bfd_vma. */
399 1.1 skrll bfd_vma reloc_unsigned_max =
400 1.1 skrll (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
401 1.1 skrll
402 1.1 skrll if ((bfd_vma) check > reloc_unsigned_max)
403 1.1 skrll flag = bfd_reloc_overflow;
404 1.1 skrll }
405 1.1 skrll break;
406 1.1 skrll case complain_overflow_bitfield:
407 1.1 skrll {
408 1.1 skrll /* Assumes two's complement. This expression avoids
409 1.1 skrll overflow if howto->bitsize is the number of bits in
410 1.1 skrll bfd_vma. */
411 1.1 skrll bfd_vma reloc_bits = (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
412 1.1 skrll
413 1.1 skrll if (((bfd_vma) check & ~reloc_bits) != 0
414 1.1 skrll && (((bfd_vma) check & ~reloc_bits)
415 1.1 skrll != (-(bfd_vma) 1 & ~reloc_bits)))
416 1.1 skrll {
417 1.1 skrll /* The above right shift is incorrect for a signed
418 1.1 skrll value. See if turning on the upper bits fixes the
419 1.1 skrll overflow. */
420 1.1 skrll if (howto->rightshift > howto->bitpos
421 1.1 skrll && (bfd_signed_vma) relocation < 0)
422 1.1 skrll {
423 1.1 skrll check |= ((bfd_vma) - 1
424 1.1 skrll & ~((bfd_vma) - 1
425 1.1 skrll >> (howto->rightshift - howto->bitpos)));
426 1.1 skrll if (((bfd_vma) check & ~reloc_bits)
427 1.1 skrll != (-(bfd_vma) 1 & ~reloc_bits))
428 1.1 skrll flag = bfd_reloc_overflow;
429 1.1 skrll }
430 1.1 skrll else
431 1.1 skrll flag = bfd_reloc_overflow;
432 1.1 skrll }
433 1.1 skrll }
434 1.1 skrll break;
435 1.1 skrll default:
436 1.1 skrll abort ();
437 1.1 skrll }
438 1.1 skrll }
439 1.1 skrll
440 1.1 skrll /* Either we are relocating all the way, or we don't want to apply
441 1.1 skrll the relocation to the reloc entry (probably because there isn't
442 1.1 skrll any room in the output format to describe addends to relocs). */
443 1.1 skrll
444 1.1 skrll /* The cast to bfd_vma avoids a bug in the Alpha OSF/1 C compiler
445 1.1 skrll (OSF version 1.3, compiler version 3.11). It miscompiles the
446 1.1 skrll following program:
447 1.1 skrll
448 1.1 skrll struct str
449 1.1 skrll {
450 1.1 skrll unsigned int i0;
451 1.1 skrll } s = { 0 };
452 1.1 skrll
453 1.1 skrll int
454 1.1 skrll main ()
455 1.1 skrll {
456 1.1 skrll unsigned long x;
457 1.1 skrll
458 1.1 skrll x = 0x100000000;
459 1.1 skrll x <<= (unsigned long) s.i0;
460 1.1 skrll if (x == 0)
461 1.1 skrll printf ("failed\n");
462 1.1 skrll else
463 1.1 skrll printf ("succeeded (%lx)\n", x);
464 1.1 skrll }
465 1.1 skrll */
466 1.1 skrll
467 1.1 skrll relocation >>= (bfd_vma) howto->rightshift;
468 1.1 skrll
469 1.1 skrll /* Shift everything up to where it's going to be used. */
470 1.1 skrll relocation <<= (bfd_vma) howto->bitpos;
471 1.1 skrll
472 1.1 skrll /* Wait for the day when all have the mask in them. */
473 1.1 skrll
474 1.1 skrll /* What we do:
475 1.1 skrll i instruction to be left alone
476 1.1 skrll o offset within instruction
477 1.1 skrll r relocation offset to apply
478 1.1 skrll S src mask
479 1.1 skrll D dst mask
480 1.1 skrll N ~dst mask
481 1.1 skrll A part 1
482 1.1 skrll B part 2
483 1.1 skrll R result
484 1.1 skrll
485 1.1 skrll Do this:
486 1.1.1.5 christos i i i i i o o o o o from bfd_get<size>
487 1.1.1.5 christos and S S S S S to get the size offset we want
488 1.1.1.5 christos + r r r r r r r r r r to get the final value to place
489 1.1.1.5 christos and D D D D D to chop to right size
490 1.1 skrll -----------------------
491 1.1 skrll A A A A A
492 1.1 skrll And this:
493 1.1.1.5 christos ... i i i i i o o o o o from bfd_get<size>
494 1.1.1.5 christos and N N N N N get instruction
495 1.1 skrll -----------------------
496 1.1 skrll ... B B B B B
497 1.1 skrll
498 1.1 skrll And then:
499 1.1 skrll B B B B B
500 1.1.1.5 christos or A A A A A
501 1.1 skrll -----------------------
502 1.1.1.5 christos R R R R R R R R R R put into bfd_put<size>. */
503 1.1 skrll
504 1.1.1.7 christos if (howto->negate)
505 1.1.1.7 christos relocation = -relocation;
506 1.1.1.7 christos
507 1.1 skrll #define DOIT(x) \
508 1.1 skrll x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) + relocation) & howto->dst_mask))
509 1.1 skrll
510 1.1 skrll location = (bfd_byte *) data + addr;
511 1.1.1.8 christos switch (bfd_get_reloc_size (howto))
512 1.1 skrll {
513 1.1 skrll case 0:
514 1.1.1.8 christos break;
515 1.1.1.8 christos
516 1.1.1.8 christos case 1:
517 1.1 skrll {
518 1.1 skrll bfd_vma x = get_data (location, 1);
519 1.1 skrll DOIT (x);
520 1.1 skrll put_data ((bfd_vma) x, location, 1);
521 1.1 skrll }
522 1.1 skrll break;
523 1.1 skrll
524 1.1.1.8 christos case 2:
525 1.1 skrll if (relocation)
526 1.1 skrll {
527 1.1 skrll bfd_vma x = get_data (location, 2);
528 1.1 skrll DOIT (x);
529 1.1 skrll put_data ((bfd_vma) x, location, 2);
530 1.1 skrll }
531 1.1 skrll break;
532 1.1.1.8 christos case 4:
533 1.1 skrll if (relocation)
534 1.1 skrll {
535 1.1 skrll bfd_vma x = get_data (location, 4);
536 1.1 skrll DOIT (x);
537 1.1 skrll put_data ((bfd_vma) x, location, 4);
538 1.1 skrll }
539 1.1 skrll break;
540 1.1 skrll
541 1.1.1.8 christos case 8:
542 1.1 skrll #ifdef BFD64
543 1.1 skrll if (relocation)
544 1.1 skrll {
545 1.1 skrll bfd_vma x = get_data (location, 8);
546 1.1 skrll DOIT (x);
547 1.1 skrll put_data (x, location, 8);
548 1.1 skrll }
549 1.1 skrll #else
550 1.1 skrll abort ();
551 1.1 skrll #endif
552 1.1 skrll break;
553 1.1 skrll default:
554 1.1 skrll return bfd_reloc_other;
555 1.1 skrll }
556 1.1 skrll if ((howto->complain_on_overflow != complain_overflow_dont) && overflow)
557 1.1 skrll return bfd_reloc_overflow;
558 1.1 skrll
559 1.1 skrll return flag;
560 1.1 skrll }
561 1.1 skrll
562 1.1 skrll /* Relocate a given location using a given value and howto. */
563 1.1 skrll
564 1.1 skrll bfd_reloc_status_type
565 1.1.1.2 christos _bfd_do_ns32k_reloc_contents (reloc_howto_type *howto,
566 1.1.1.2 christos bfd *input_bfd ATTRIBUTE_UNUSED,
567 1.1.1.2 christos bfd_vma relocation,
568 1.1.1.2 christos bfd_byte *location,
569 1.1.1.2 christos bfd_vma (*get_data) (bfd_byte *, int),
570 1.1.1.2 christos void (*put_data) (bfd_vma, bfd_byte *, int))
571 1.1 skrll {
572 1.1 skrll int size;
573 1.1 skrll bfd_vma x;
574 1.1.1.8 christos bool overflow;
575 1.1 skrll
576 1.1.1.8 christos if (howto->negate)
577 1.1 skrll relocation = -relocation;
578 1.1 skrll
579 1.1 skrll /* Get the value we are going to relocate. */
580 1.1 skrll size = bfd_get_reloc_size (howto);
581 1.1 skrll switch (size)
582 1.1 skrll {
583 1.1 skrll default:
584 1.1 skrll abort ();
585 1.1.1.3 christos case 0:
586 1.1.1.3 christos return bfd_reloc_ok;
587 1.1 skrll case 1:
588 1.1 skrll case 2:
589 1.1 skrll case 4:
590 1.1 skrll #ifdef BFD64
591 1.1 skrll case 8:
592 1.1 skrll #endif
593 1.1 skrll x = get_data (location, size);
594 1.1 skrll break;
595 1.1 skrll }
596 1.1 skrll
597 1.1 skrll /* Check for overflow. FIXME: We may drop bits during the addition
598 1.1 skrll which we don't check for. We must either check at every single
599 1.1 skrll operation, which would be tedious, or we must do the computations
600 1.1 skrll in a type larger than bfd_vma, which would be inefficient. */
601 1.1.1.8 christos overflow = false;
602 1.1 skrll if (howto->complain_on_overflow != complain_overflow_dont)
603 1.1 skrll {
604 1.1 skrll bfd_vma check;
605 1.1 skrll bfd_signed_vma signed_check;
606 1.1 skrll bfd_vma add;
607 1.1 skrll bfd_signed_vma signed_add;
608 1.1 skrll
609 1.1 skrll if (howto->rightshift == 0)
610 1.1 skrll {
611 1.1 skrll check = relocation;
612 1.1 skrll signed_check = (bfd_signed_vma) relocation;
613 1.1 skrll }
614 1.1 skrll else
615 1.1 skrll {
616 1.1 skrll /* Drop unwanted bits from the value we are relocating to. */
617 1.1 skrll check = relocation >> howto->rightshift;
618 1.1 skrll
619 1.1 skrll /* If this is a signed value, the rightshift just dropped
620 1.1 skrll leading 1 bits (assuming twos complement). */
621 1.1 skrll if ((bfd_signed_vma) relocation >= 0)
622 1.1 skrll signed_check = check;
623 1.1 skrll else
624 1.1 skrll signed_check = (check
625 1.1 skrll | ((bfd_vma) - 1
626 1.1 skrll & ~((bfd_vma) - 1 >> howto->rightshift)));
627 1.1 skrll }
628 1.1 skrll
629 1.1 skrll /* Get the value from the object file. */
630 1.1 skrll add = x & howto->src_mask;
631 1.1 skrll
632 1.1 skrll /* Get the value from the object file with an appropriate sign.
633 1.1 skrll The expression involving howto->src_mask isolates the upper
634 1.1 skrll bit of src_mask. If that bit is set in the value we are
635 1.1 skrll adding, it is negative, and we subtract out that number times
636 1.1 skrll two. If src_mask includes the highest possible bit, then we
637 1.1 skrll can not get the upper bit, but that does not matter since
638 1.1 skrll signed_add needs no adjustment to become negative in that
639 1.1 skrll case. */
640 1.1 skrll signed_add = add;
641 1.1 skrll if ((add & (((~howto->src_mask) >> 1) & howto->src_mask)) != 0)
642 1.1 skrll signed_add -= (((~howto->src_mask) >> 1) & howto->src_mask) << 1;
643 1.1 skrll
644 1.1 skrll /* Add the value from the object file, shifted so that it is a
645 1.1 skrll straight number. */
646 1.1 skrll if (howto->bitpos == 0)
647 1.1 skrll {
648 1.1 skrll check += add;
649 1.1 skrll signed_check += signed_add;
650 1.1 skrll }
651 1.1 skrll else
652 1.1 skrll {
653 1.1 skrll check += add >> howto->bitpos;
654 1.1 skrll
655 1.1 skrll /* For the signed case we use ADD, rather than SIGNED_ADD,
656 1.1 skrll to avoid warnings from SVR4 cc. This is OK since we
657 1.1 skrll explicitly handle the sign bits. */
658 1.1 skrll if (signed_add >= 0)
659 1.1 skrll signed_check += add >> howto->bitpos;
660 1.1 skrll else
661 1.1 skrll signed_check += ((add >> howto->bitpos)
662 1.1 skrll | ((bfd_vma) - 1
663 1.1 skrll & ~((bfd_vma) - 1 >> howto->bitpos)));
664 1.1 skrll }
665 1.1 skrll
666 1.1 skrll switch (howto->complain_on_overflow)
667 1.1 skrll {
668 1.1 skrll case complain_overflow_signed:
669 1.1 skrll {
670 1.1 skrll /* Assumes two's complement. */
671 1.1 skrll bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
672 1.1 skrll bfd_signed_vma reloc_signed_min = ~reloc_signed_max;
673 1.1 skrll
674 1.1 skrll if (signed_check > reloc_signed_max
675 1.1 skrll || signed_check < reloc_signed_min)
676 1.1.1.8 christos overflow = true;
677 1.1 skrll }
678 1.1 skrll break;
679 1.1 skrll case complain_overflow_unsigned:
680 1.1 skrll {
681 1.1 skrll /* Assumes two's complement. This expression avoids
682 1.1 skrll overflow if howto->bitsize is the number of bits in
683 1.1 skrll bfd_vma. */
684 1.1 skrll bfd_vma reloc_unsigned_max =
685 1.1 skrll (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
686 1.1 skrll
687 1.1 skrll if (check > reloc_unsigned_max)
688 1.1.1.8 christos overflow = true;
689 1.1 skrll }
690 1.1 skrll break;
691 1.1 skrll case complain_overflow_bitfield:
692 1.1 skrll {
693 1.1 skrll /* Assumes two's complement. This expression avoids
694 1.1 skrll overflow if howto->bitsize is the number of bits in
695 1.1 skrll bfd_vma. */
696 1.1 skrll bfd_vma reloc_bits = (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
697 1.1 skrll
698 1.1 skrll if ((check & ~reloc_bits) != 0
699 1.1 skrll && (((bfd_vma) signed_check & ~reloc_bits)
700 1.1 skrll != (-(bfd_vma) 1 & ~reloc_bits)))
701 1.1.1.8 christos overflow = true;
702 1.1 skrll }
703 1.1 skrll break;
704 1.1 skrll default:
705 1.1 skrll abort ();
706 1.1 skrll }
707 1.1 skrll }
708 1.1 skrll
709 1.1 skrll /* Put RELOCATION in the right bits. */
710 1.1 skrll relocation >>= (bfd_vma) howto->rightshift;
711 1.1 skrll relocation <<= (bfd_vma) howto->bitpos;
712 1.1 skrll
713 1.1 skrll /* Add RELOCATION to the right bits of X. */
714 1.1 skrll x = ((x & ~howto->dst_mask)
715 1.1 skrll | (((x & howto->src_mask) + relocation) & howto->dst_mask));
716 1.1 skrll
717 1.1 skrll /* Put the relocated value back in the object file. */
718 1.1 skrll switch (size)
719 1.1 skrll {
720 1.1 skrll default:
721 1.1 skrll case 0:
722 1.1 skrll abort ();
723 1.1 skrll case 1:
724 1.1 skrll case 2:
725 1.1 skrll case 4:
726 1.1 skrll #ifdef BFD64
727 1.1 skrll case 8:
728 1.1 skrll #endif
729 1.1 skrll put_data (x, location, size);
730 1.1 skrll break;
731 1.1 skrll }
732 1.1 skrll
733 1.1 skrll return overflow ? bfd_reloc_overflow : bfd_reloc_ok;
734 1.1 skrll }
735 1.1 skrll
736 1.1 skrll bfd_reloc_status_type
737 1.1.1.2 christos _bfd_ns32k_reloc_disp (bfd *abfd,
738 1.1.1.2 christos arelent *reloc_entry,
739 1.1.1.2 christos struct bfd_symbol *symbol,
740 1.1.1.2 christos void * data,
741 1.1.1.2 christos asection *input_section,
742 1.1.1.2 christos bfd *output_bfd,
743 1.1.1.2 christos char **error_message)
744 1.1 skrll {
745 1.1 skrll return do_ns32k_reloc (abfd, reloc_entry, symbol, data, input_section,
746 1.1 skrll output_bfd, error_message,
747 1.1 skrll _bfd_ns32k_get_displacement,
748 1.1 skrll _bfd_ns32k_put_displacement);
749 1.1 skrll }
750 1.1 skrll
751 1.1 skrll bfd_reloc_status_type
752 1.1.1.2 christos _bfd_ns32k_reloc_imm (bfd *abfd,
753 1.1.1.2 christos arelent *reloc_entry,
754 1.1.1.2 christos struct bfd_symbol *symbol,
755 1.1.1.2 christos void * data,
756 1.1.1.2 christos asection *input_section,
757 1.1.1.2 christos bfd *output_bfd,
758 1.1.1.2 christos char **error_message)
759 1.1 skrll {
760 1.1 skrll return do_ns32k_reloc (abfd, reloc_entry, symbol, data, input_section,
761 1.1 skrll output_bfd, error_message, _bfd_ns32k_get_immediate,
762 1.1 skrll _bfd_ns32k_put_immediate);
763 1.1 skrll }
764 1.1 skrll
765 1.1 skrll bfd_reloc_status_type
766 1.1.1.2 christos _bfd_ns32k_final_link_relocate (reloc_howto_type *howto,
767 1.1.1.2 christos bfd *input_bfd,
768 1.1.1.2 christos asection *input_section,
769 1.1.1.2 christos bfd_byte *contents,
770 1.1.1.2 christos bfd_vma address,
771 1.1.1.2 christos bfd_vma value,
772 1.1.1.2 christos bfd_vma addend)
773 1.1 skrll {
774 1.1 skrll bfd_vma relocation;
775 1.1 skrll
776 1.1 skrll /* Sanity check the address. */
777 1.1 skrll if (address > bfd_get_section_limit (input_bfd, input_section))
778 1.1 skrll return bfd_reloc_outofrange;
779 1.1 skrll
780 1.1 skrll /* This function assumes that we are dealing with a basic relocation
781 1.1 skrll against a symbol. We want to compute the value of the symbol to
782 1.1 skrll relocate to. This is just VALUE, the value of the symbol, plus
783 1.1 skrll ADDEND, any addend associated with the reloc. */
784 1.1 skrll relocation = value + addend;
785 1.1 skrll
786 1.1 skrll /* If the relocation is PC relative, we want to set RELOCATION to
787 1.1 skrll the distance between the symbol (currently in RELOCATION) and the
788 1.1.1.6 christos location we are relocating. If pcrel_offset is FALSE we do not
789 1.1 skrll need to subtract out the offset of the location within the
790 1.1 skrll section (which is just ADDRESS). */
791 1.1 skrll if (howto->pc_relative)
792 1.1 skrll {
793 1.1 skrll relocation -= (input_section->output_section->vma
794 1.1 skrll + input_section->output_offset);
795 1.1 skrll if (howto->pcrel_offset)
796 1.1 skrll relocation -= address;
797 1.1 skrll }
798 1.1 skrll
799 1.1 skrll return _bfd_ns32k_relocate_contents (howto, input_bfd, relocation,
800 1.1 skrll contents + address);
801 1.1 skrll }
802