1 /* write.c - emit .o file
3 Copyright (C) 1986, 1987, 1990, 1991, 1992 Free Software Foundation, Inc.
5 This file is part of GAS, the GNU Assembler.
7 GAS 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, or (at your option)
12 GAS 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.
17 You should have received a copy of the GNU General Public License
18 along with GAS; see the file COPYING. If not, write to
19 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
21 /* This thing should be set up to do byteordering correctly. But... */
26 #include "output-file.h"
28 /* The NOP_OPCODE is for the alignment fill value.
29 * fill it a nop instruction so that the disassembler does not choke
33 #define NOP_OPCODE 0x00
37 struct frag *text_frag_root;
38 struct frag *data_frag_root;
39 struct frag *bss_frag_root;
41 struct frag *text_last_frag; /* Last frag in segment. */
42 struct frag *data_last_frag; /* Last frag in segment. */
43 static struct frag *bss_last_frag; /* Last frag in segment. */
46 static object_headers headers;
48 long string_byte_count;
50 static char *the_object_file;
52 char *next_object_file_charP; /* Tracks object file bytes. */
55 int magic_number_for_object_file = DEFAULT_MAGIC_NUMBER_FOR_OBJECT_FILE;
58 static int is_dnrange PARAMS ((struct frag * f1, struct frag * f2));
59 static long fixup_segment PARAMS ((fixS * fixP, segT this_segment_type));
60 static relax_addressT relax_align PARAMS ((relax_addressT addr, long align));
61 void relax_segment PARAMS ((struct frag * seg_frag_root, segT seg_type));
66 * Create a fixS in obstack 'notes'.
69 fix_new (frag, where, size, add_symbol, sub_symbol, offset, pcrel, r_type)
70 fragS *frag; /* Which frag? */
71 int where; /* Where in that frag? */
72 short int size; /* 1, 2, or 4 usually. */
73 symbolS *add_symbol; /* X_add_symbol. */
74 symbolS *sub_symbol; /* X_subtract_symbol. */
75 long offset; /* X_add_number. */
76 int pcrel; /* TRUE if PC-relative relocation. */
77 int r_type; /* Relocation type */
81 fixP = (fixS *) obstack_alloc (¬es, sizeof (fixS));
84 fixP->fx_where = where;
86 fixP->fx_addsy = add_symbol;
87 fixP->fx_subsy = sub_symbol;
88 fixP->fx_offset = offset;
89 fixP->fx_pcrel = pcrel;
90 #if defined(TC_SPARC) || defined(TC_A29K) || defined( NEED_FX_R_TYPE)
91 fixP->fx_r_type = r_type;
93 /* JF these 'cuz of the NS32K stuff */
95 fixP->fx_pcrel_adjust = 0;
97 fixP->fx_bit_fixP = 0;
99 /* usually, we want relocs sorted numerically, but while
100 comparing to older versions of gas that have relocs
101 reverse sorted, it is convenient to have this compile
102 time option. xoxorich. */
104 #ifdef REVERSE_SORT_RELOCS
106 fixP->fx_next = *seg_fix_rootP;
107 *seg_fix_rootP = fixP;
109 #else /* REVERSE_SORT_RELOCS */
111 fixP->fx_next = NULL;
114 (*seg_fix_tailP)->fx_next = fixP;
116 *seg_fix_rootP = fixP;
117 *seg_fix_tailP = fixP;
119 #endif /* REVERSE_SORT_RELOCS */
128 remove_subsegs (head, seg, root, last)
135 fragS *prev_frag = &dummy;
136 *root = head->frch_root;
137 while (head && head->frch_seg == seg)
139 prev_frag->fr_next = head->frch_root;
141 prev_frag = head->frch_last;
142 head = head->frch_next;
145 prev_frag->fr_next = 0;
151 register struct frchain *frchainP; /* Track along all frchains. */
152 register fragS *fragP; /* Track along all frags. */
153 register struct frchain *next_frchainP;
154 register fragS **prev_fragPP;
156 long object_file_size;
160 * Under VMS we try to be compatible with VAX-11 "C". Thus, we
161 * call a routine to check for the definition of the procedure
162 * "_main", and if so -- fix it up so that it can be program
165 VMS_Check_For_Main ();
168 * After every sub-segment, we fake an ".align ...". This conforms to
169 * BSD4.2 brane-damage. We then fake ".fill 0" because that is the
170 * kind of frag that requires least thought. ".align" frags like to
171 * have a following frag since that makes calculating their intended
174 #ifndef SUB_SEGMENT_ALIGN
175 #define SUB_SEGMENT_ALIGN (2)
177 for (frchainP = frchain_root; frchainP; frchainP = frchainP->frch_next)
181 * Under VAX/VMS, the linker (and PSECT specifications)
182 * take care of correctly aligning the segments.
183 * Doing the alignment here (on initialized data) can
184 * mess up the calculation of global data PSECT sizes.
186 #undef SUB_SEGMENT_ALIGN
187 #define SUB_SEGMENT_ALIGN ((frchainP->frch_seg != SEG_DATA) ? 2 : 0)
189 subseg_new (frchainP->frch_seg, frchainP->frch_subseg);
190 frag_align (SUB_SEGMENT_ALIGN, NOP_OPCODE);
191 /* frag_align will have left a new frag. */
192 /* Use this last frag for an empty ".fill". */
194 * For this segment ...
195 * Create a last frag. Do not leave a "being filled in frag".
197 frag_wane (frag_now);
198 frag_now->fr_fix = 0;
199 know (frag_now->fr_next == NULL);
200 /* know( frags . obstack_c_base == frags . obstack_c_next_free ); */
201 /* Above shows we haven't left a half-completed object on obstack. */
202 } /* walk the frag chain */
205 * From now on, we don't care about sub-segments.
206 * Build one frag chain for each segment. Linked thru fr_next.
207 * We know that there is at least 1 text frchain & at least 1 data
211 remove_subsegs (frchain_root, SEG_TEXT, &text_frag_root, &text_last_frag);
212 remove_subsegs (data0_frchainP, SEG_DATA, &data_frag_root, &data_last_frag);
213 remove_subsegs (bss0_frchainP, SEG_BSS, &bss_frag_root, &bss_last_frag);
216 * We have two segments. If user gave -R flag, then we must put the
217 * data frags into the text segment. Do this before relaxing so
218 * we know to take advantage of -R and make shorter addresses.
225 text_last_frag->fr_next = data_frag_root;
226 text_last_frag = data_last_frag;
227 data_last_frag = NULL;
228 data_frag_root = NULL;
231 for (tmp = text_fix_root; tmp->fx_next; tmp = tmp->fx_next);;
232 tmp->fx_next = data_fix_root;
233 text_fix_tail = data_fix_tail;
236 text_fix_root = data_fix_root;
237 data_fix_root = NULL;
240 relax_segment (text_frag_root, SEG_TEXT);
241 relax_segment (data_frag_root, SEG_DATA);
242 relax_segment (bss_frag_root, SEG_BSS);
244 * Now the addresses of frags are correct within the segment.
247 know (text_last_frag->fr_type == rs_fill && text_last_frag->fr_offset == 0);
248 H_SET_TEXT_SIZE (&headers, text_last_frag->fr_address);
249 text_last_frag->fr_address = H_GET_TEXT_SIZE (&headers);
252 * Join the 2 segments into 1 huge segment.
253 * To do this, re-compute every rn_address in the SEG_DATA frags.
254 * Then join the data frags after the text frags.
256 * Determine a_data [length of data segment].
260 register relax_addressT slide;
262 know ((text_last_frag->fr_type == rs_fill) && (text_last_frag->fr_offset == 0));
264 H_SET_DATA_SIZE (&headers, data_last_frag->fr_address);
265 data_last_frag->fr_address = H_GET_DATA_SIZE (&headers);
266 slide = H_GET_TEXT_SIZE (&headers); /* & in file of the data segment. */
268 #define RoundUp(N,S) (((N)+(S)-1)&-(S))
269 /* For b.out: If the data section has a strict alignment
270 requirement, its load address in the .o file will be
271 rounded up from the size of the text section. These
272 two values are *not* the same! Similarly for the bss
274 slide = RoundUp (slide, 1 << section_alignment[SEG_DATA]);
277 for (fragP = data_frag_root; fragP; fragP = fragP->fr_next)
279 fragP->fr_address += slide;
280 } /* for each data frag */
282 know (text_last_frag != 0);
283 text_last_frag->fr_next = data_frag_root;
287 H_SET_DATA_SIZE (&headers, 0);
291 /* See above comments on b.out data section address. */
294 if (data_last_frag == 0)
295 bss_vma = H_GET_TEXT_SIZE (&headers);
297 bss_vma = data_last_frag->fr_address;
298 bss_vma = RoundUp (bss_vma, 1 << section_alignment[SEG_BSS]);
299 bss_address_frag.fr_address = bss_vma;
302 bss_address_frag.fr_address = (H_GET_TEXT_SIZE (&headers) +
303 H_GET_DATA_SIZE (&headers));
306 /* Slide all the frags */
309 relax_addressT slide = bss_address_frag.fr_address;
311 for (fragP = bss_frag_root; fragP; fragP = fragP->fr_next)
313 fragP->fr_address += slide;
314 } /* for each bss frag */
320 H_SET_BSS_SIZE (&headers,
321 bss_last_frag->fr_address - bss_frag_root->fr_address);
323 H_SET_BSS_SIZE (&headers, 0);
327 * Crawl the symbol chain.
329 * For each symbol whose value depends on a frag, take the address of
330 * that frag and subsume it into the value of the symbol.
331 * After this, there is just one way to lookup a symbol value.
332 * Values are left in their final state for object file emission.
333 * We adjust the values of 'L' local symbols, even if we do
334 * not intend to emit them to the object file, because their values
335 * are needed for fix-ups.
337 * Unless we saw a -L flag, remove all symbols that begin with 'L'
338 * from the symbol chain. (They are still pointed to by the fixes.)
340 * Count the remaining symbols.
341 * Assign a symbol number to each symbol.
342 * Count the number of string-table chars we will emit.
343 * Put this info into the headers as appropriate.
346 know (zero_address_frag.fr_address == 0);
347 string_byte_count = sizeof (string_byte_count);
349 obj_crawl_symbol_chain (&headers);
351 if (string_byte_count == sizeof (string_byte_count))
353 string_byte_count = 0;
354 } /* if no strings, then no count. */
356 H_SET_STRING_SIZE (&headers, string_byte_count);
359 * Addresses of frags now reflect addresses we use in the object file.
360 * Symbol values are correct.
361 * Scan the frags, converting any ".org"s and ".align"s to ".fill"s.
362 * Also converting any machine-dependent frags using md_convert_frag();
364 subseg_change (SEG_TEXT, 0);
366 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
368 switch (fragP->fr_type)
373 HANDLE_ALIGN (fragP);
375 fragP->fr_type = rs_fill;
376 know (fragP->fr_var == 1);
377 know (fragP->fr_next != NULL);
379 fragP->fr_offset = (fragP->fr_next->fr_address
387 case rs_machine_dependent:
388 md_convert_frag (&headers, fragP);
390 know ((fragP->fr_next == NULL) || ((fragP->fr_next->fr_address - fragP->fr_address) == fragP->fr_fix));
393 * After md_convert_frag, we make the frag into a ".space 0".
394 * Md_convert_frag() should set up any fixSs and constants
400 #ifndef WORKING_DOT_WORD
403 struct broken_word *lie;
404 extern md_short_jump_size;
405 extern md_long_jump_size;
407 if (fragP->fr_subtype)
409 fragP->fr_fix += md_short_jump_size;
410 for (lie = (struct broken_word *) (fragP->fr_symbol); lie && lie->dispfrag == fragP; lie = lie->next_broken_word)
412 fragP->fr_fix += md_long_jump_size;
420 BAD_CASE (fragP->fr_type);
422 } /* switch (fr_type) */
424 if (!((fragP->fr_next == NULL)
426 || (fragP->fr_next == data_frag_root)
428 || ((fragP->fr_next->fr_address - fragP->fr_address)
429 == (fragP->fr_fix + (fragP->fr_offset * fragP->fr_var)))))
431 fprintf (stderr, "assertion failed: file `%s', line %d\n",
432 __FILE__, __LINE__ - 4);
435 } /* for each frag. */
437 #ifndef WORKING_DOT_WORD
439 struct broken_word *lie;
440 struct broken_word **prevP;
442 prevP = &broken_words;
443 for (lie = broken_words; lie; lie = lie->next_broken_word)
447 fix_new_ns32k (lie->frag,
448 lie->word_goes_here - lie->frag->fr_literal,
455 # if defined(TC_SPARC) || defined(TC_A29K) || defined(NEED_FX_R_TYPE)
456 fix_new (lie->frag, lie->word_goes_here - lie->frag->fr_literal,
458 lie->sub, lie->addnum,
461 fix_new (lie->frag, lie->word_goes_here - lie->frag->fr_literal,
463 lie->sub, lie->addnum,
466 # endif /* tc_sparc|tc_a29k|need_fx_r_type */
467 #endif /* TC_NS32K */
468 /* md_number_to_chars(lie->word_goes_here,
469 S_GET_VALUE(lie->add)
471 - S_GET_VALUE(lie->sub),
473 *prevP = lie->next_broken_word;
476 prevP = &(lie->next_broken_word);
478 for (lie = broken_words; lie;)
480 struct broken_word *untruth;
483 long from_addr, to_addr;
486 extern md_short_jump_size;
487 extern md_long_jump_size;
489 fragP = lie->dispfrag;
491 /* Find out how many broken_words go here */
493 for (untruth = lie; untruth && untruth->dispfrag == fragP; untruth = untruth->next_broken_word)
494 if (untruth->added == 1)
497 table_ptr = lie->dispfrag->fr_opcode;
498 table_addr = lie->dispfrag->fr_address + (table_ptr - lie->dispfrag->fr_literal);
499 /* Create the jump around the long jumps */
500 /* This is a short jump from table_ptr+0 to table_ptr+n*long_jump_size */
501 from_addr = table_addr;
502 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
503 md_create_short_jump (table_ptr, from_addr, to_addr, lie->dispfrag, lie->add);
504 table_ptr += md_short_jump_size;
505 table_addr += md_short_jump_size;
507 for (m = 0; lie && lie->dispfrag == fragP; m++, lie = lie->next_broken_word)
511 /* Patch the jump table */
512 /* This is the offset from ??? to table_ptr+0 */
514 - S_GET_VALUE (lie->sub);
515 md_number_to_chars (lie->word_goes_here, to_addr, 2);
516 for (untruth = lie->next_broken_word; untruth && untruth->dispfrag == fragP; untruth = untruth->next_broken_word)
518 if (untruth->use_jump == lie)
519 md_number_to_chars (untruth->word_goes_here, to_addr, 2);
522 /* Install the long jump */
523 /* this is a long jump from table_ptr+0 to the final target */
524 from_addr = table_addr;
525 to_addr = S_GET_VALUE (lie->add) + lie->addnum;
526 md_create_long_jump (table_ptr, from_addr, to_addr, lie->dispfrag, lie->add);
527 table_ptr += md_long_jump_size;
528 table_addr += md_long_jump_size;
532 #endif /* not WORKING_DOT_WORD */
537 * Scan every FixS performing fixups. We had to wait until now to do
538 * this because md_convert_frag() may have made some fixSs.
542 subseg_change (SEG_TEXT, 0);
543 trsize = md_reloc_size * fixup_segment (text_fix_root,
545 subseg_change (SEG_DATA, 0);
546 drsize = md_reloc_size * fixup_segment (data_fix_root,
548 H_SET_RELOCATION_SIZE (&headers, trsize, drsize);
550 /* FIXME move this stuff into the pre-write-hook */
551 H_SET_MAGIC_NUMBER (&headers, magic_number_for_object_file);
552 H_SET_ENTRY_POINT (&headers, 0);
554 obj_pre_write_hook (&headers); /* extra coff stuff */
555 if ((had_warnings () && flagseen['Z'])
556 || had_errors () > 0)
560 as_warn ("%d error%s, %d warning%s, generating bad object file.\n",
561 had_errors (), had_errors () == 1 ? "" : "s",
562 had_warnings (), had_warnings () == 1 ? "" : "s");
566 as_fatal ("%d error%s, %d warning%s, no object file generated.\n",
567 had_errors (), had_errors () == 1 ? "" : "s",
568 had_warnings (), had_warnings () == 1 ? "" : "s");
569 } /* on want output */
570 } /* on error condition */
572 object_file_size = H_GET_FILE_SIZE (&headers);
573 next_object_file_charP = the_object_file = xmalloc (object_file_size);
575 output_file_create (out_file_name);
577 obj_header_append (&next_object_file_charP, &headers);
579 know ((next_object_file_charP - the_object_file) == H_GET_HEADER_SIZE (&headers));
584 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
587 register char *fill_literal;
588 register long fill_size;
590 know (fragP->fr_type == rs_fill);
591 append (&next_object_file_charP, fragP->fr_literal, (unsigned long) fragP->fr_fix);
592 fill_literal = fragP->fr_literal + fragP->fr_fix;
593 fill_size = fragP->fr_var;
594 know (fragP->fr_offset >= 0);
596 for (count = fragP->fr_offset; count; count--)
598 append (&next_object_file_charP, fill_literal, (unsigned long) fill_size);
601 } /* for each code frag. */
603 know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers)));
608 obj_emit_relocations (&next_object_file_charP, text_fix_root, (relax_addressT) 0);
609 know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers) + H_GET_TEXT_RELOCATION_SIZE (&headers)));
611 /* Make addresses in data relocation directives relative to beginning of
612 * first data fragment, not end of last text fragment: alignment of the
613 * start of the data segment may place a gap between the segments.
615 obj_emit_relocations (&next_object_file_charP, data_fix_root, data0_frchainP->frch_root->fr_address);
617 obj_emit_relocations (&next_object_file_charP, data_fix_root, text_last_frag->fr_address);
620 know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers) + H_GET_TEXT_RELOCATION_SIZE (&headers) + H_GET_DATA_RELOCATION_SIZE (&headers)));
623 * Emit line number entries.
625 OBJ_EMIT_LINENO (&next_object_file_charP, lineno_rootP, the_object_file);
626 know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers) + H_GET_TEXT_RELOCATION_SIZE (&headers) + H_GET_DATA_RELOCATION_SIZE (&headers) + H_GET_LINENO_SIZE (&headers)));
631 obj_emit_symbols (&next_object_file_charP, symbol_rootP);
632 know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers) + H_GET_TEXT_RELOCATION_SIZE (&headers) + H_GET_DATA_RELOCATION_SIZE (&headers) + H_GET_LINENO_SIZE (&headers) + H_GET_SYMBOL_TABLE_SIZE (&headers)));
638 if (string_byte_count > 0)
640 obj_emit_strings (&next_object_file_charP);
641 } /* only if we have a string table */
643 /* know((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE(&headers) + H_GET_TEXT_SIZE(&headers) + H_GET_DATA_SIZE(&headers) + H_GET_TEXT_RELOCATION_SIZE(&headers) + H_GET_DATA_RELOCATION_SIZE(&headers) + H_GET_LINENO_SIZE(&headers) + H_GET_SYMBOL_TABLE_SIZE(&headers) + H_GET_STRING_SIZE(&headers)));
645 /* know(next_object_file_charP == the_object_file + object_file_size);*/
648 bfd_seek (stdoutput, 0, 0);
649 bfd_write (the_object_file, 1, object_file_size, stdoutput);
652 /* Write the data to the file */
653 output_file_append (the_object_file, object_file_size, out_file_name);
656 output_file_close (out_file_name);
657 } /* non vms output */
660 * Now do the VMS-dependent part of writing the object file
662 VMS_write_object_file (H_GET_TEXT_SIZE (&headers),
663 H_GET_DATA_SIZE (&headers),
664 H_GET_BSS_SIZE (&headers),
665 text_frag_root, data_frag_root);
667 } /* write_object_file() */
675 * Now we have a segment, not a crowd of sub-segments, we can make fr_address
680 * After this, all frags in this segment have addresses that are correct
681 * within the segment. Since segments live in different file addresses,
682 * these frag addresses may not be the same as final object-file addresses.
688 relax_segment (segment_frag_root, segment)
689 struct frag *segment_frag_root;
690 segT segment; /* SEG_DATA or SEG_TEXT */
692 register struct frag *fragP;
693 register relax_addressT address;
694 #ifndef MANY_SEGMENTS
695 know (segment == SEG_DATA || segment == SEG_TEXT || segment == SEG_BSS);
697 /* In case md_estimate_size_before_relax() wants to make fixSs. */
698 subseg_change (segment, 0);
700 /* For each frag in segment: count and store (a 1st guess of)
703 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
705 fragP->fr_address = address;
706 address += fragP->fr_fix;
708 switch (fragP->fr_type)
711 address += fragP->fr_offset * fragP->fr_var;
715 address += relax_align (address, fragP->fr_offset);
719 /* Assume .org is nugatory. It will grow with 1st relax. */
722 case rs_machine_dependent:
723 address += md_estimate_size_before_relax (fragP, segment);
726 #ifndef WORKING_DOT_WORD
727 /* Broken words don't concern us yet */
733 BAD_CASE (fragP->fr_type);
735 } /* switch(fr_type) */
736 } /* for each frag in the segment */
740 long stretch; /* May be any size, 0 or negative. */
741 /* Cumulative number of addresses we have */
742 /* relaxed this pass. */
743 /* We may have relaxed more than one address. */
744 long stretched; /* Have we stretched on this pass? */
745 /* This is 'cuz stretch may be zero, when, in fact some piece of code
746 grew, and another shrank. If a branch instruction doesn't fit anymore,
747 we could be scrod. */
751 stretch = stretched = 0;
752 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
755 unsigned long was_address;
762 was_address = fragP->fr_address;
763 address = fragP->fr_address += stretch;
764 symbolP = fragP->fr_symbol;
765 offset = fragP->fr_offset;
767 switch (fragP->fr_type)
769 case rs_fill: /* .fill never relaxes. */
773 #ifndef WORKING_DOT_WORD
774 /* JF: This is RMS's idea. I do *NOT* want to be blamed
775 for it I do not want to write it. I do not want to have
776 anything to do with it. This is not the proper way to
777 implement this misfeature. */
780 struct broken_word *lie;
781 struct broken_word *untruth;
782 extern int md_short_jump_size;
783 extern int md_long_jump_size;
785 /* Yes this is ugly (storing the broken_word pointer
786 in the symbol slot). Still, this whole chunk of
787 code is ugly, and I don't feel like doing anything
788 about it. Think of it as stubbornness in action. */
790 for (lie = (struct broken_word *) (fragP->fr_symbol);
791 lie && lie->dispfrag == fragP;
792 lie = lie->next_broken_word)
798 offset = (lie->add->sy_frag->fr_address
799 + S_GET_VALUE (lie->add)
801 - (lie->sub->sy_frag->fr_address
802 + S_GET_VALUE (lie->sub)));
803 if (offset <= -32768 || offset >= 32767)
806 as_warn (".word %s-%s+%ld didn't fit",
807 S_GET_NAME (lie->add),
808 S_GET_NAME (lie->sub),
811 if (fragP->fr_subtype == 0)
814 growth += md_short_jump_size;
816 for (untruth = lie->next_broken_word;
817 untruth && untruth->dispfrag == lie->dispfrag;
818 untruth = untruth->next_broken_word)
819 if ((untruth->add->sy_frag == lie->add->sy_frag)
820 && S_GET_VALUE (untruth->add) == S_GET_VALUE (lie->add))
823 untruth->use_jump = lie;
825 growth += md_long_jump_size;
830 } /* case rs_broken_word */
833 growth = (relax_align ((relax_addressT) (address + fragP->fr_fix), offset)
834 - relax_align ((relax_addressT) (was_address + fragP->fr_fix), offset));
844 know ((S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE) || (S_GET_SEGMENT (symbolP) == SEG_DATA) || (S_GET_SEGMENT (symbolP) == SEG_TEXT) || S_GET_SEGMENT (symbolP) == SEG_BSS);
845 know (symbolP->sy_frag);
846 know (!(S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE) || (symbolP->sy_frag == &zero_address_frag));
848 target += S_GET_VALUE (symbolP)
849 + symbolP->sy_frag->fr_address;
850 } /* if we have a symbol */
852 know (fragP->fr_next);
853 after = fragP->fr_next->fr_address;
854 growth = ((target - after) > 0) ? (target - after) : 0;
855 /* Growth may be -ve, but variable part of frag cannot have
856 fewer than 0 chars. That is, we can't .org backwards. */
858 growth -= stretch; /* This is an absolute growth factor */
861 case rs_machine_dependent:
863 const relax_typeS *this_type;
864 const relax_typeS *start_type;
865 relax_substateT next_state;
866 relax_substateT this_state;
868 this_state = fragP->fr_subtype;
869 start_type = this_type = md_relax_table + this_state;
874 #ifndef MANY_SEGMENTS
875 know ((S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE) || (S_GET_SEGMENT (symbolP) == SEG_DATA) || (S_GET_SEGMENT (symbolP) == SEG_BSS) || (S_GET_SEGMENT (symbolP) == SEG_TEXT));
877 know (symbolP->sy_frag);
878 know (!(S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE) || symbolP->sy_frag == &zero_address_frag);
880 S_GET_VALUE (symbolP)
881 + symbolP->sy_frag->fr_address;
883 /* If frag has yet to be reached on this pass,
884 assume it will move by STRETCH just as we did.
885 If this is not so, it will be because some frag
886 between grows, and that will force another pass. */
888 /* JF was just address */
889 /* JF also added is_dnrange hack */
890 /* There's gotta be a better/faster/etc way
893 because I ran into a zero-length frag (fr_fix=0)
894 which was created when the obstack needed a new
895 chunk JUST AFTER the opcode of a branch. Since
896 fr_fix is zero, fr_address of this frag is the same
897 as fr_address of the next frag. This
898 zero-length frag was variable and jumped to .+2
899 (in the next frag), but since the > comparison
900 below failed (the two were =, not >), "stretch"
901 was not added to the target. Stretch was 178, so
902 the offset appeared to be .-176 instead, which did
903 not fit into a byte branch, so the assembler
904 relaxed the branch to a word. This didn't compare
905 with what happened when the same source file was
906 assembled on other machines, which is how I found it.
907 You might want to think about what other places have
908 trouble with zero length frags... */
910 if (symbolP->sy_frag->fr_address >= was_address
911 && is_dnrange (fragP, symbolP->sy_frag))
915 } /* if there's a symbol attached */
917 aim = target - address - fragP->fr_fix;
918 /* The displacement is affected by the instruction size
919 for the 32k architecture. I think we ought to be able
920 to add fragP->fr_pcrel_adjust in all cases (it should be
921 zero if not used), but just in case it breaks something
922 else we'll put this inside #ifdef NS32K ... #endif */
924 aim += fragP->fr_pcrel_adjust;
925 #endif /* TC_NS32K */
929 /* Look backwards. */
930 for (next_state = this_type->rlx_more; next_state;)
931 if (aim >= this_type->rlx_backward)
935 /* Grow to next state. */
936 this_state = next_state;
937 this_type = md_relax_table + this_state;
938 next_state = this_type->rlx_more;
943 #ifdef M68K_AIM_KLUDGE
944 M68K_AIM_KLUDGE (aim, this_state, this_type);
947 for (next_state = this_type->rlx_more; next_state;)
948 if (aim <= this_type->rlx_forward)
952 /* Grow to next state. */
953 this_state = next_state;
954 this_type = md_relax_table + this_state;
955 next_state = this_type->rlx_more;
959 growth = this_type->rlx_length - start_type->rlx_length;
961 fragP->fr_subtype = this_state;
966 BAD_CASE (fragP->fr_type);
974 } /* For each frag in the segment. */
976 while (stretched); /* Until nothing further to relax. */
980 * We now have valid fr_address'es for each frag.
984 * All fr_address's are correct, relative to their own segment.
985 * We have made all the fixS we will ever make.
987 } /* relax_segment() */
990 * Relax_align. Advance location counter to next address that has 'alignment'
991 * lowest order bits all 0s.
994 /* How many addresses does the .align take? */
995 static relax_addressT
996 relax_align (address, alignment)
997 register relax_addressT address; /* Address now. */
998 register long alignment; /* Alignment (binary). */
1000 relax_addressT mask;
1001 relax_addressT new_address;
1003 mask = ~((~0) << alignment);
1004 new_address = (address + mask) & (~mask);
1006 /* We must provide lots of padding, so the linker can discard it
1007 when needed. The linker will not add extra space, ever. */
1008 new_address += (1 << alignment);
1009 return (new_address - address);
1010 } /* relax_align() */
1014 Go through all the fixS's in a segment and see which ones can be
1015 handled now. (These consist of fixS where we have since discovered
1016 the value of a symbol, or the address of the frag involved.)
1017 For each one, call md_apply_fix to put the fix into the frag data.
1019 Result is a count of how many relocation structs will be needed to
1020 handle the remaining fixS's that we couldn't completely handle here.
1021 These will be output later by emit_relocations(). */
1024 fixup_segment (fixP, this_segment_type)
1025 register fixS *fixP;
1026 segT this_segment_type; /* N_TYPE bits for segment. */
1028 register long seg_reloc_count;
1029 register symbolS *add_symbolP;
1030 register symbolS *sub_symbolP;
1031 register long add_number;
1033 register char *place;
1034 register long where;
1035 register char pcrel;
1036 register fragS *fragP;
1037 register segT add_symbol_segment = SEG_ABSOLUTE;
1039 /* FIXME: remove this line *//* fixS *orig = fixP; */
1040 seg_reloc_count = 0;
1042 /* If the linker is doing the relaxing, we must not do any fixups */
1045 for (; fixP; fixP = fixP->fx_next)
1052 for (; fixP; fixP = fixP->fx_next)
1054 fragP = fixP->fx_frag;
1056 where = fixP->fx_where;
1057 place = fragP->fr_literal + where;
1058 size = fixP->fx_size;
1059 add_symbolP = fixP->fx_addsy;
1061 if (fixP->fx_callj && TC_S_IS_CALLNAME (add_symbolP))
1063 /* Relocation should be done via the
1064 associated 'bal' entry point
1067 if (!TC_S_IS_BALNAME (tc_get_bal_of_call (add_symbolP)))
1069 as_bad ("No 'bal' entry point for leafproc %s",
1070 S_GET_NAME (add_symbolP));
1073 fixP->fx_addsy = add_symbolP = tc_get_bal_of_call (add_symbolP);
1074 } /* callj relocation */
1076 sub_symbolP = fixP->fx_subsy;
1077 add_number = fixP->fx_offset;
1078 pcrel = fixP->fx_pcrel;
1082 add_symbol_segment = S_GET_SEGMENT (add_symbolP);
1083 } /* if there is an addend */
1090 if (S_GET_SEGMENT (sub_symbolP) != SEG_ABSOLUTE)
1092 as_bad ("Negative of non-absolute symbol %s", S_GET_NAME (sub_symbolP));
1093 } /* not absolute */
1095 add_number -= S_GET_VALUE (sub_symbolP);
1097 /* if sub_symbol is in the same segment that add_symbol
1098 and add_symbol is either in DATA, TEXT, BSS or ABSOLUTE */
1100 else if ((S_GET_SEGMENT (sub_symbolP) == add_symbol_segment)
1101 && (SEG_NORMAL (add_symbol_segment)
1102 || (add_symbol_segment == SEG_ABSOLUTE)))
1104 /* Difference of 2 symbols from same segment. */
1105 /* Can't make difference of 2 undefineds: 'value' means */
1106 /* something different for N_UNDF. */
1108 /* Makes no sense to use the difference of 2 arbitrary symbols
1109 * as the target of a call instruction.
1113 as_bad ("callj to difference of 2 symbols");
1115 #endif /* TC_I960 */
1116 add_number += S_GET_VALUE (add_symbolP) -
1117 S_GET_VALUE (sub_symbolP);
1120 fixP->fx_addsy = NULL;
1124 /* Different segments in subtraction. */
1125 know (!(S_IS_EXTERNAL (sub_symbolP) && (S_GET_SEGMENT (sub_symbolP) == SEG_ABSOLUTE)));
1127 if ((S_GET_SEGMENT (sub_symbolP) == SEG_ABSOLUTE))
1129 add_number -= S_GET_VALUE (sub_symbolP);
1133 as_bad ("Can't emit reloc {- %s-seg symbol \"%s\"} @ file address %d.",
1134 segment_name (S_GET_SEGMENT (sub_symbolP)),
1135 S_GET_NAME (sub_symbolP), fragP->fr_address + where);
1138 } /* if sub_symbolP */
1142 if (add_symbol_segment == this_segment_type && pcrel)
1145 * This fixup was made when the symbol's segment was
1146 * SEG_UNKNOWN, but it is now in the local segment.
1147 * So we know how to do the address without relocation.
1150 /* reloc_callj() may replace a 'call' with a 'calls' or a 'bal',
1151 * in which cases it modifies *fixP as appropriate. In the case
1152 * of a 'calls', no further work is required, and *fixP has been
1153 * set up to make the rest of the code below a no-op.
1156 #endif /* TC_I960 */
1158 add_number += S_GET_VALUE (add_symbolP);
1159 add_number -= md_pcrel_from (fixP);
1160 pcrel = 0; /* Lie. Don't want further pcrel processing. */
1161 fixP->fx_addsy = NULL; /* No relocations please. */
1165 switch (add_symbol_segment)
1169 reloc_callj (fixP); /* See comment about reloc_callj() above*/
1170 #endif /* TC_I960 */
1171 add_number += S_GET_VALUE (add_symbolP);
1172 fixP->fx_addsy = NULL;
1177 add_number += S_GET_VALUE (add_symbolP);
1182 if ((int) fixP->fx_bit_fixP == 13)
1184 /* This is a COBR instruction. They have only a
1185 * 13-bit displacement and are only to be used
1186 * for local branches: flag as error, don't generate
1189 as_bad ("can't use COBR format with external label");
1190 fixP->fx_addsy = NULL; /* No relocations please. */
1193 #endif /* TC_I960 */
1197 if (S_IS_COMMON (add_symbolP))
1198 add_number += S_GET_VALUE (add_symbolP);
1199 #endif /* TE_I386AIX */
1200 #endif /* OBJ_COFF */
1206 } /* switch on symbol seg */
1207 } /* if not in local seg */
1208 } /* if there was a + symbol */
1212 add_number -= md_pcrel_from (fixP);
1213 if (add_symbolP == 0)
1215 fixP->fx_addsy = &abs_symbol;
1217 } /* if there's an add_symbol */
1220 if (!fixP->fx_bit_fixP)
1223 (add_number & ~0xFF) && ((add_number & ~0xFF) != (-1 & ~0xFF))) ||
1225 (add_number & ~0xFFFF) && ((add_number & ~0xFFFF) != (-1 & ~0xFFFF))))
1227 as_bad ("Value of %d too large for field of %d bytes at 0x%x",
1228 add_number, size, fragP->fr_address + where);
1229 } /* generic error checking */
1230 #ifdef WARN_SIGNED_OVERFLOW_WORD
1231 /* Warn if a .word value is too large when
1232 treated as a signed number. We already
1233 know it is not too negative. This is to
1234 catch over-large switches generated by gcc
1238 && add_number > 0x7fff)
1239 as_bad ("Signed .word overflow; switch may be too large; %d at 0x%x",
1240 add_number, fragP->fr_address + where);
1242 } /* not a bit fix */
1244 md_apply_fix (fixP, add_number);
1245 } /* For each fixS in this segment. */
1252 /* two relocs per callj under coff. */
1253 for (fixP = topP; fixP; fixP = fixP->fx_next)
1255 if (fixP->fx_callj && fixP->fx_addsy != 0)
1258 } /* if callj and not already fixed. */
1259 } /* for each fix */
1261 #endif /* TC_I960 */
1263 #endif /* OBJ_COFF */
1264 return (seg_reloc_count);
1265 } /* fixup_segment() */
1275 if (f1->fr_next == f2)
1280 } /* is_dnrange() */
1282 /* Append a string onto another string, bumping the pointer along. */
1284 append (charPP, fromP, length)
1287 unsigned long length;
1290 { /* Don't trust memcpy() of 0 chars. */
1291 memcpy (*charPP, fromP, (int) length);
1296 int section_alignment[SEG_MAXIMUM_ORDINAL];
1299 * This routine records the largest alignment seen for each segment.
1300 * If the beginning of the segment is aligned on the worst-case
1301 * boundary, all of the other alignments within it will work. At
1302 * least one object format really uses this info.
1305 record_alignment (seg, align)
1306 segT seg; /* Segment to which alignment pertains */
1307 int align; /* Alignment, as a power of 2
1308 * (e.g., 1 => 2-byte boundary, 2 => 4-byte boundary, etc.)
1312 if (align > section_alignment[(int) seg])
1314 section_alignment[(int) seg] = align;
1315 } /* if highest yet */
1318 } /* record_alignment() */
1320 /* end of write.c */