1 /* BFD support for the ns32k architecture.
2 Copyright 1990, 1991, 1994, 1995, 1998, 1999, 2000, 2001, 2002, 2003,
3 2004, 2005 Free Software Foundation, Inc.
4 Almost totally rewritten by Ian Dall from initial work
7 This file is part of BFD, the Binary File Descriptor library.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
28 #define N(machine, printable, d, next) \
29 { 32, 32, 8, bfd_arch_ns32k, machine, "ns32k",printable,3,d,bfd_default_compatible,bfd_default_scan, next, }
31 static const bfd_arch_info_type arch_info_struct[] =
33 N(32532,"ns32k:32532",TRUE, 0), /* The word ns32k will match this too. */
36 const bfd_arch_info_type bfd_ns32k_arch =
37 N(32032,"ns32k:32032",FALSE, &arch_info_struct[0]);
39 static bfd_reloc_status_type do_ns32k_reloc
40 PARAMS ((bfd *, arelent *, struct bfd_symbol *, PTR, asection *,
42 bfd_vma (*) (bfd_byte *, int),
43 void (*) (bfd_vma, bfd_byte *, int)));
46 _bfd_ns32k_get_displacement (buffer, size)
55 value = ((*buffer & 0x7f) ^ 0x40) - 0x40;
59 value = ((*buffer++ & 0x3f) ^ 0x20) - 0x20;
60 value = (value << 8) | (0xff & *buffer);
64 value = ((*buffer++ & 0x3f) ^ 0x20) - 0x20;
65 value = (value << 8) | (0xff & *buffer++);
66 value = (value << 8) | (0xff & *buffer++);
67 value = (value << 8) | (0xff & *buffer);
79 _bfd_ns32k_put_displacement (value, buffer, size)
94 *buffer++ = (value >> 8);
99 value |= (bfd_vma) 0xc0000000;
100 *buffer++ = (value >> 24);
101 *buffer++ = (value >> 16);
102 *buffer++ = (value >> 8);
110 _bfd_ns32k_get_immediate (buffer, size)
119 value = (value << 8) | (*buffer++ & 0xff);
120 value = (value << 8) | (*buffer++ & 0xff);
122 value = (value << 8) | (*buffer++ & 0xff);
124 value = (value << 8) | (*buffer++ & 0xff);
133 _bfd_ns32k_put_immediate (value, buffer, size)
142 *buffer-- = (value & 0xff); value >>= 8;
143 *buffer-- = (value & 0xff); value >>= 8;
145 *buffer-- = (value & 0xff); value >>= 8;
147 *buffer-- = (value & 0xff); value >>= 8;
151 /* This is just like the standard perform_relocation except we
152 use get_data and put_data which know about the ns32k storage
153 methods. This is probably a lot more complicated than it
156 static bfd_reloc_status_type
157 do_ns32k_reloc (abfd, reloc_entry, symbol, data, input_section, output_bfd,
158 error_message, get_data, put_data)
160 arelent *reloc_entry;
161 struct bfd_symbol *symbol;
163 asection *input_section;
165 char **error_message ATTRIBUTE_UNUSED;
166 bfd_vma (*get_data) PARAMS ((bfd_byte *, int));
167 void (*put_data) PARAMS ((bfd_vma, bfd_byte *, int));
171 bfd_reloc_status_type flag = bfd_reloc_ok;
172 bfd_size_type addr = reloc_entry->address;
173 bfd_vma output_base = 0;
174 reloc_howto_type *howto = reloc_entry->howto;
175 asection *reloc_target_output_section;
178 if ((symbol->section == &bfd_abs_section)
179 && output_bfd != (bfd *) NULL)
181 reloc_entry->address += input_section->output_offset;
185 /* If we are not producing relocatable output, return an error if
186 the symbol is not defined. An undefined weak symbol is
187 considered to have a value of zero (SVR4 ABI, p. 4-27). */
188 if (symbol->section == &bfd_und_section
189 && (symbol->flags & BSF_WEAK) == 0
190 && output_bfd == (bfd *) NULL)
191 flag = bfd_reloc_undefined;
193 /* Is the address of the relocation really within the section? */
194 if (reloc_entry->address > bfd_get_section_limit (abfd, input_section))
195 return bfd_reloc_outofrange;
197 /* Work out which section the relocation is targeted at and the
198 initial relocation command value. */
200 /* Get symbol value. (Common symbols are special.) */
201 if (bfd_is_com_section (symbol->section))
204 relocation = symbol->value;
206 reloc_target_output_section = symbol->section->output_section;
208 /* Convert input-section-relative symbol value to absolute. */
209 if (output_bfd != NULL && ! howto->partial_inplace)
212 output_base = reloc_target_output_section->vma;
214 relocation += output_base + symbol->section->output_offset;
216 /* Add in supplied addend. */
217 relocation += reloc_entry->addend;
219 /* Here the variable relocation holds the final address of the
220 symbol we are relocating against, plus any addend. */
222 if (howto->pc_relative)
224 /* This is a PC relative relocation. We want to set RELOCATION
225 to the distance between the address of the symbol and the
226 location. RELOCATION is already the address of the symbol.
228 We start by subtracting the address of the section containing
231 If pcrel_offset is set, we must further subtract the position
232 of the location within the section. Some targets arrange for
233 the addend to be the negative of the position of the location
234 within the section; for example, i386-aout does this. For
235 i386-aout, pcrel_offset is FALSE. Some other targets do not
236 include the position of the location; for example, m88kbcs,
237 or ELF. For those targets, pcrel_offset is TRUE.
239 If we are producing relocatable output, then we must ensure
240 that this reloc will be correctly computed when the final
241 relocation is done. If pcrel_offset is FALSE we want to wind
242 up with the negative of the location within the section,
243 which means we must adjust the existing addend by the change
244 in the location within the section. If pcrel_offset is TRUE
245 we do not want to adjust the existing addend at all.
247 FIXME: This seems logical to me, but for the case of
248 producing relocatable output it is not what the code
249 actually does. I don't want to change it, because it seems
250 far too likely that something will break. */
252 input_section->output_section->vma + input_section->output_offset;
254 if (howto->pcrel_offset)
255 relocation -= reloc_entry->address;
258 if (output_bfd != (bfd *) NULL)
260 if (! howto->partial_inplace)
262 /* This is a partial relocation, and we want to apply the relocation
263 to the reloc entry rather than the raw data. Modify the reloc
264 inplace to reflect what we now know. */
265 reloc_entry->addend = relocation;
266 reloc_entry->address += input_section->output_offset;
271 /* This is a partial relocation, but inplace, so modify the
274 If we've relocated with a symbol with a section, change
275 into a ref to the section belonging to the symbol. */
277 reloc_entry->address += input_section->output_offset;
280 if (abfd->xvec->flavour == bfd_target_coff_flavour)
282 /* For m68k-coff, the addend was being subtracted twice during
283 relocation with -r. Removing the line below this comment
284 fixes that problem; see PR 2953.
286 However, Ian wrote the following, regarding removing the line
287 below, which explains why it is still enabled: --djm
289 If you put a patch like that into BFD you need to check all
290 the COFF linkers. I am fairly certain that patch will break
291 coff-i386 (e.g., SCO); see coff_i386_reloc in coff-i386.c
292 where I worked around the problem in a different way. There
293 may very well be a reason that the code works as it does.
295 Hmmm. The first obvious point is that bfd_perform_relocation
296 should not have any tests that depend upon the flavour. It's
297 seem like entirely the wrong place for such a thing. The
298 second obvious point is that the current code ignores the
299 reloc addend when producing relocatable output for COFF.
300 That's peculiar. In fact, I really have no idea what the
301 point of the line you want to remove is.
303 A typical COFF reloc subtracts the old value of the symbol
304 and adds in the new value to the location in the object file
305 (if it's a pc relative reloc it adds the difference between
306 the symbol value and the location). When relocating we need
307 to preserve that property.
309 BFD handles this by setting the addend to the negative of the
310 old value of the symbol. Unfortunately it handles common
311 symbols in a non-standard way (it doesn't subtract the old
312 value) but that's a different story (we can't change it
313 without losing backward compatibility with old object files)
314 (coff-i386 does subtract the old value, to be compatible with
315 existing coff-i386 targets, like SCO).
317 So everything works fine when not producing relocatable
318 output. When we are producing relocatable output, logically
319 we should do exactly what we do when not producing
320 relocatable output. Therefore, your patch is correct. In
321 fact, it should probably always just set reloc_entry->addend
322 to 0 for all cases, since it is, in fact, going to add the
323 value into the object file. This won't hurt the COFF code,
324 which doesn't use the addend; I'm not sure what it will do
325 to other formats (the thing to check for would be whether
326 any formats both use the addend and set partial_inplace).
328 When I wanted to make coff-i386 produce relocatable output,
329 I ran into the problem that you are running into: I wanted
330 to remove that line. Rather than risk it, I made the
331 coff-i386 relocs use a special function; it's coff_i386_reloc
332 in coff-i386.c. The function specifically adds the addend
333 field into the object file, knowing that bfd_perform_relocation
334 is not going to. If you remove that line, then coff-i386.c
335 will wind up adding the addend field in twice. It's trivial
336 to fix; it just needs to be done.
338 The problem with removing the line is just that it may break
339 some working code. With BFD it's hard to be sure of anything.
340 The right way to deal with this is simply to build and test at
341 least all the supported COFF targets. It should be
342 straightforward if time and disk space consuming. For each
345 2) generate some executable, and link it using -r (I would
346 probably use paranoia.o and link against newlib/libc.a,
347 which for all the supported targets would be available in
348 /usr/cygnus/progressive/H-host/target/lib/libc.a).
349 3) make the change to reloc.c
350 4) rebuild the linker
352 6) if the resulting object files are the same, you have at
353 least made it no worse
354 7) if they are different you have to figure out which
356 relocation -= reloc_entry->addend;
357 reloc_entry->addend = 0;
361 reloc_entry->addend = relocation;
367 reloc_entry->addend = 0;
370 /* FIXME: This overflow checking is incomplete, because the value
371 might have overflowed before we get here. For a correct check we
372 need to compute the value in a size larger than bitsize, but we
373 can't reasonably do that for a reloc the same size as a host
375 FIXME: We should also do overflow checking on the result after
376 adding in the value contained in the object file. */
377 if (howto->complain_on_overflow != complain_overflow_dont)
381 /* Get the value that will be used for the relocation, but
382 starting at bit position zero. */
383 if (howto->rightshift > howto->bitpos)
384 check = relocation >> (howto->rightshift - howto->bitpos);
386 check = relocation << (howto->bitpos - howto->rightshift);
387 switch (howto->complain_on_overflow)
389 case complain_overflow_signed:
391 /* Assumes two's complement. */
392 bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
393 bfd_signed_vma reloc_signed_min = ~reloc_signed_max;
395 /* The above right shift is incorrect for a signed value.
396 Fix it up by forcing on the upper bits. */
397 if (howto->rightshift > howto->bitpos
398 && (bfd_signed_vma) relocation < 0)
399 check |= ((bfd_vma) - 1
401 >> (howto->rightshift - howto->bitpos)));
402 if ((bfd_signed_vma) check > reloc_signed_max
403 || (bfd_signed_vma) check < reloc_signed_min)
404 flag = bfd_reloc_overflow;
407 case complain_overflow_unsigned:
409 /* Assumes two's complement. This expression avoids
410 overflow if howto->bitsize is the number of bits in
412 bfd_vma reloc_unsigned_max =
413 (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
415 if ((bfd_vma) check > reloc_unsigned_max)
416 flag = bfd_reloc_overflow;
419 case complain_overflow_bitfield:
421 /* Assumes two's complement. This expression avoids
422 overflow if howto->bitsize is the number of bits in
424 bfd_vma reloc_bits = (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
426 if (((bfd_vma) check & ~reloc_bits) != 0
427 && (((bfd_vma) check & ~reloc_bits)
428 != (-(bfd_vma) 1 & ~reloc_bits)))
430 /* The above right shift is incorrect for a signed
431 value. See if turning on the upper bits fixes the
433 if (howto->rightshift > howto->bitpos
434 && (bfd_signed_vma) relocation < 0)
436 check |= ((bfd_vma) - 1
438 >> (howto->rightshift - howto->bitpos)));
439 if (((bfd_vma) check & ~reloc_bits)
440 != (-(bfd_vma) 1 & ~reloc_bits))
441 flag = bfd_reloc_overflow;
444 flag = bfd_reloc_overflow;
453 /* Either we are relocating all the way, or we don't want to apply
454 the relocation to the reloc entry (probably because there isn't
455 any room in the output format to describe addends to relocs). */
457 /* The cast to bfd_vma avoids a bug in the Alpha OSF/1 C compiler
458 (OSF version 1.3, compiler version 3.11). It miscompiles the
472 x <<= (unsigned long) s.i0;
476 printf ("succeeded (%lx)\n", x);
480 relocation >>= (bfd_vma) howto->rightshift;
482 /* Shift everything up to where it's going to be used. */
483 relocation <<= (bfd_vma) howto->bitpos;
485 /* Wait for the day when all have the mask in them. */
488 i instruction to be left alone
489 o offset within instruction
490 r relocation offset to apply
499 i i i i i o o o o o from bfd_get<size>
500 and S S S S S to get the size offset we want
501 + r r r r r r r r r r to get the final value to place
502 and D D D D D to chop to right size
503 -----------------------
506 ... i i i i i o o o o o from bfd_get<size>
507 and N N N N N get instruction
508 -----------------------
514 -----------------------
515 R R R R R R R R R R put into bfd_put<size>. */
518 x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) + relocation) & howto->dst_mask))
520 location = (bfd_byte *) data + addr;
525 bfd_vma x = get_data (location, 1);
527 put_data ((bfd_vma) x, location, 1);
534 bfd_vma x = get_data (location, 2);
536 put_data ((bfd_vma) x, location, 2);
542 bfd_vma x = get_data (location, 4);
544 put_data ((bfd_vma) x, location, 4);
549 bfd_vma x = get_data (location, 4);
550 relocation = -relocation;
552 put_data ((bfd_vma) x, location, 4);
564 bfd_vma x = get_data (location, 8);
566 put_data (x, location, 8);
573 return bfd_reloc_other;
575 if ((howto->complain_on_overflow != complain_overflow_dont) && overflow)
576 return bfd_reloc_overflow;
581 /* Relocate a given location using a given value and howto. */
583 bfd_reloc_status_type
584 _bfd_do_ns32k_reloc_contents (howto, input_bfd, relocation, location,
586 reloc_howto_type *howto;
587 bfd *input_bfd ATTRIBUTE_UNUSED;
590 bfd_vma (*get_data) PARAMS ((bfd_byte *, int));
591 void (*put_data) PARAMS ((bfd_vma, bfd_byte *, int));
595 bfd_boolean overflow;
597 /* If the size is negative, negate RELOCATION. This isn't very
600 relocation = -relocation;
602 /* Get the value we are going to relocate. */
603 size = bfd_get_reloc_size (howto);
615 x = get_data (location, size);
619 /* Check for overflow. FIXME: We may drop bits during the addition
620 which we don't check for. We must either check at every single
621 operation, which would be tedious, or we must do the computations
622 in a type larger than bfd_vma, which would be inefficient. */
624 if (howto->complain_on_overflow != complain_overflow_dont)
627 bfd_signed_vma signed_check;
629 bfd_signed_vma signed_add;
631 if (howto->rightshift == 0)
634 signed_check = (bfd_signed_vma) relocation;
638 /* Drop unwanted bits from the value we are relocating to. */
639 check = relocation >> howto->rightshift;
641 /* If this is a signed value, the rightshift just dropped
642 leading 1 bits (assuming twos complement). */
643 if ((bfd_signed_vma) relocation >= 0)
644 signed_check = check;
646 signed_check = (check
648 & ~((bfd_vma) - 1 >> howto->rightshift)));
651 /* Get the value from the object file. */
652 add = x & howto->src_mask;
654 /* Get the value from the object file with an appropriate sign.
655 The expression involving howto->src_mask isolates the upper
656 bit of src_mask. If that bit is set in the value we are
657 adding, it is negative, and we subtract out that number times
658 two. If src_mask includes the highest possible bit, then we
659 can not get the upper bit, but that does not matter since
660 signed_add needs no adjustment to become negative in that
663 if ((add & (((~howto->src_mask) >> 1) & howto->src_mask)) != 0)
664 signed_add -= (((~howto->src_mask) >> 1) & howto->src_mask) << 1;
666 /* Add the value from the object file, shifted so that it is a
668 if (howto->bitpos == 0)
671 signed_check += signed_add;
675 check += add >> howto->bitpos;
677 /* For the signed case we use ADD, rather than SIGNED_ADD,
678 to avoid warnings from SVR4 cc. This is OK since we
679 explicitly handle the sign bits. */
681 signed_check += add >> howto->bitpos;
683 signed_check += ((add >> howto->bitpos)
685 & ~((bfd_vma) - 1 >> howto->bitpos)));
688 switch (howto->complain_on_overflow)
690 case complain_overflow_signed:
692 /* Assumes two's complement. */
693 bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1;
694 bfd_signed_vma reloc_signed_min = ~reloc_signed_max;
696 if (signed_check > reloc_signed_max
697 || signed_check < reloc_signed_min)
701 case complain_overflow_unsigned:
703 /* Assumes two's complement. This expression avoids
704 overflow if howto->bitsize is the number of bits in
706 bfd_vma reloc_unsigned_max =
707 (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
709 if (check > reloc_unsigned_max)
713 case complain_overflow_bitfield:
715 /* Assumes two's complement. This expression avoids
716 overflow if howto->bitsize is the number of bits in
718 bfd_vma reloc_bits = (((1 << (howto->bitsize - 1)) - 1) << 1) | 1;
720 if ((check & ~reloc_bits) != 0
721 && (((bfd_vma) signed_check & ~reloc_bits)
722 != (-(bfd_vma) 1 & ~reloc_bits)))
731 /* Put RELOCATION in the right bits. */
732 relocation >>= (bfd_vma) howto->rightshift;
733 relocation <<= (bfd_vma) howto->bitpos;
735 /* Add RELOCATION to the right bits of X. */
736 x = ((x & ~howto->dst_mask)
737 | (((x & howto->src_mask) + relocation) & howto->dst_mask));
739 /* Put the relocated value back in the object file. */
751 put_data (x, location, size);
755 return overflow ? bfd_reloc_overflow : bfd_reloc_ok;
758 bfd_reloc_status_type
759 _bfd_ns32k_reloc_disp (abfd, reloc_entry, symbol, data, input_section,
760 output_bfd, error_message)
762 arelent *reloc_entry;
763 struct bfd_symbol *symbol;
765 asection *input_section;
767 char **error_message;
769 return do_ns32k_reloc (abfd, reloc_entry, symbol, data, input_section,
770 output_bfd, error_message,
771 _bfd_ns32k_get_displacement,
772 _bfd_ns32k_put_displacement);
775 bfd_reloc_status_type
776 _bfd_ns32k_reloc_imm (abfd, reloc_entry, symbol, data, input_section,
777 output_bfd, error_message)
779 arelent *reloc_entry;
780 struct bfd_symbol *symbol;
782 asection *input_section;
784 char **error_message;
786 return do_ns32k_reloc (abfd, reloc_entry, symbol, data, input_section,
787 output_bfd, error_message, _bfd_ns32k_get_immediate,
788 _bfd_ns32k_put_immediate);
791 bfd_reloc_status_type
792 _bfd_ns32k_final_link_relocate (howto, input_bfd, input_section, contents,
793 address, value, addend)
794 reloc_howto_type *howto;
796 asection *input_section;
804 /* Sanity check the address. */
805 if (address > bfd_get_section_limit (input_bfd, input_section))
806 return bfd_reloc_outofrange;
808 /* This function assumes that we are dealing with a basic relocation
809 against a symbol. We want to compute the value of the symbol to
810 relocate to. This is just VALUE, the value of the symbol, plus
811 ADDEND, any addend associated with the reloc. */
812 relocation = value + addend;
814 /* If the relocation is PC relative, we want to set RELOCATION to
815 the distance between the symbol (currently in RELOCATION) and the
816 location we are relocating. Some targets (e.g., i386-aout)
817 arrange for the contents of the section to be the negative of the
818 offset of the location within the section; for such targets
819 pcrel_offset is FALSE. Other targets (e.g., m88kbcs or ELF)
820 simply leave the contents of the section as zero; for such
821 targets pcrel_offset is TRUE. If pcrel_offset is FALSE we do not
822 need to subtract out the offset of the location within the
823 section (which is just ADDRESS). */
824 if (howto->pc_relative)
826 relocation -= (input_section->output_section->vma
827 + input_section->output_offset);
828 if (howto->pcrel_offset)
829 relocation -= address;
832 return _bfd_ns32k_relocate_contents (howto, input_bfd, relocation,