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. */
54 int magic_number_for_object_file = DEFAULT_MAGIC_NUMBER_FOR_OBJECT_FILE;
56 static int is_dnrange PARAMS ((struct frag *f1, struct frag *f2));
57 static long fixup_segment PARAMS ((fixS *fixP, segT this_segment_type));
58 static relax_addressT relax_align PARAMS ((relax_addressT addr, long align));
59 void relax_segment PARAMS ((struct frag *seg_frag_root, segT seg_type));
64 * Create a fixS in obstack 'notes'.
66 fixS *fix_new(frag, where, size, add_symbol, sub_symbol, offset, pcrel, r_type)
67 fragS *frag; /* Which frag? */
68 int where; /* Where in that frag? */
69 short int size; /* 1, 2, or 4 usually. */
70 symbolS *add_symbol; /* X_add_symbol. */
71 symbolS *sub_symbol; /* X_subtract_symbol. */
72 long offset; /* X_add_number. */
73 int pcrel; /* TRUE if PC-relative relocation. */
74 int r_type; /* Relocation type */
78 fixP = (fixS *) obstack_alloc(¬es, sizeof(fixS));
81 fixP->fx_where = where;
83 fixP->fx_addsy = add_symbol;
84 fixP->fx_subsy = sub_symbol;
85 fixP->fx_offset = offset;
86 fixP->fx_pcrel = pcrel;
87 #if defined(TC_SPARC) || defined(TC_A29K) || defined( NEED_FX_R_TYPE)
88 fixP->fx_r_type = r_type;
90 /* JF these 'cuz of the NS32K stuff */
92 fixP->fx_pcrel_adjust = 0;
94 fixP->fx_bit_fixP = 0;
96 /* usually, we want relocs sorted numerically, but while
97 comparing to older versions of gas that have relocs
98 reverse sorted, it is convenient to have this compile
99 time option. xoxorich. */
101 #ifdef REVERSE_SORT_RELOCS
103 fixP->fx_next = *seg_fix_rootP;
104 *seg_fix_rootP = fixP;
106 #else /* REVERSE_SORT_RELOCS */
108 fixP->fx_next = NULL;
111 (*seg_fix_tailP)->fx_next = fixP;
113 *seg_fix_rootP = fixP;
114 *seg_fix_tailP = fixP;
116 #endif /* REVERSE_SORT_RELOCS */
124 void remove_subsegs(head, seg, root, last)
131 fragS * prev_frag = &dummy;
132 *root = head->frch_root;
133 while (head && head->frch_seg == seg)
135 prev_frag->fr_next = head->frch_root;
137 prev_frag = head->frch_last;
138 head = head->frch_next;
141 prev_frag->fr_next = 0;
143 void write_object_file()
145 register struct frchain * frchainP; /* Track along all frchains. */
146 register fragS * fragP; /* Track along all frags. */
147 register struct frchain * next_frchainP;
148 register fragS * * prev_fragPP;
149 unsigned int data_siz;
151 long object_file_size;
155 * Under VMS we try to be compatible with VAX-11 "C". Thus, we
156 * call a routine to check for the definition of the procedure
157 * "_main", and if so -- fix it up so that it can be program
160 VMS_Check_For_Main();
163 * After every sub-segment, we fake an ".align ...". This conforms to
164 * BSD4.2 brane-damage. We then fake ".fill 0" because that is the
165 * kind of frag that requires least thought. ".align" frags like to
166 * have a following frag since that makes calculating their intended
169 #define SUB_SEGMENT_ALIGN (2)
170 for (frchainP = frchain_root; frchainP; frchainP = frchainP->frch_next) {
173 * Under VAX/VMS, the linker (and PSECT specifications)
174 * take care of correctly aligning the segments.
175 * Doing the alignment here (on initialized data) can
176 * mess up the calculation of global data PSECT sizes.
178 #undef SUB_SEGMENT_ALIGN
179 #define SUB_SEGMENT_ALIGN ((frchainP->frch_seg != SEG_DATA) ? 2 : 0)
181 subseg_new (frchainP->frch_seg, frchainP->frch_subseg);
182 frag_align (SUB_SEGMENT_ALIGN, NOP_OPCODE);
183 /* frag_align will have left a new frag. */
184 /* Use this last frag for an empty ".fill". */
186 * For this segment ...
187 * Create a last frag. Do not leave a "being filled in frag".
189 frag_wane (frag_now);
190 frag_now->fr_fix = 0;
191 know( frag_now->fr_next == NULL );
192 /* know( frags . obstack_c_base == frags . obstack_c_next_free ); */
193 /* Above shows we haven't left a half-completed object on obstack. */
194 } /* walk the frag chain */
197 * From now on, we don't care about sub-segments.
198 * Build one frag chain for each segment. Linked thru fr_next.
199 * We know that there is at least 1 text frchain & at least 1 data
203 remove_subsegs(frchain_root, SEG_TEXT, &text_frag_root, &text_last_frag);
204 remove_subsegs(data0_frchainP, SEG_DATA, &data_frag_root, &data_last_frag);
205 remove_subsegs(bss0_frchainP, SEG_BSS, &bss_frag_root, &bss_last_frag);
208 * We have two segments. If user gave -R flag, then we must put the
209 * data frags into the text segment. Do this before relaxing so
210 * we know to take advantage of -R and make shorter addresses.
213 if (flagseen[ 'R' ]) {
216 text_last_frag->fr_next = data_frag_root;
217 text_last_frag = data_last_frag;
218 data_last_frag = NULL;
219 data_frag_root = NULL;
221 for (tmp = text_fix_root; tmp->fx_next; tmp = tmp->fx_next) ;;
222 tmp->fx_next=data_fix_root;
223 text_fix_tail = data_fix_tail;
225 text_fix_root=data_fix_root;
229 relax_segment(text_frag_root, SEG_TEXT);
230 relax_segment(data_frag_root, SEG_DATA);
231 relax_segment(bss_frag_root, SEG_BSS);
233 * Now the addresses of frags are correct within the segment.
236 know(text_last_frag->fr_type == rs_fill && text_last_frag->fr_offset == 0);
237 H_SET_TEXT_SIZE(&headers, text_last_frag->fr_address);
238 text_last_frag->fr_address = H_GET_TEXT_SIZE(&headers);
241 * Join the 2 segments into 1 huge segment.
242 * To do this, re-compute every rn_address in the SEG_DATA frags.
243 * Then join the data frags after the text frags.
245 * Determine a_data [length of data segment].
247 if (data_frag_root) {
248 register relax_addressT slide;
250 know((text_last_frag->fr_type == rs_fill) && (text_last_frag->fr_offset == 0));
252 H_SET_DATA_SIZE(&headers, data_last_frag->fr_address);
253 data_last_frag->fr_address = H_GET_DATA_SIZE(&headers);
254 slide = H_GET_TEXT_SIZE(&headers); /* & in file of the data segment. */
256 #define RoundUp(N,S) (((N)+(S)-1)&-(S))
257 /* For b.out: If the data section has a strict alignment
258 requirement, its load address in the .o file will be
259 rounded up from the size of the text section. These
260 two values are *not* the same! Similarly for the bss
262 slide = RoundUp (slide, 1 << section_alignment[SEG_DATA]);
265 for (fragP = data_frag_root; fragP; fragP = fragP->fr_next) {
266 fragP->fr_address += slide;
267 } /* for each data frag */
269 know(text_last_frag != 0);
270 text_last_frag->fr_next = data_frag_root;
272 H_SET_DATA_SIZE(&headers,0);
277 /* See above comments on b.out data section address. */
280 if (data_last_frag == 0)
281 bss_vma = H_GET_TEXT_SIZE (&headers);
283 bss_vma = data_last_frag->fr_address;
284 bss_vma = RoundUp (bss_vma, 1 << section_alignment[SEG_BSS]);
285 bss_address_frag.fr_address = bss_vma;
288 bss_address_frag.fr_address = (H_GET_TEXT_SIZE(&headers) +
289 H_GET_DATA_SIZE(&headers));
292 /* Slide all the frags */
295 relax_addressT slide = bss_address_frag.fr_address + local_bss_counter;
297 for (fragP = bss_frag_root; fragP; fragP = fragP->fr_next)
299 fragP->fr_address += slide;
300 } /* for each bss frag */
305 local_bss_counter += bss_last_frag->fr_address - bss_frag_root->fr_address;
307 H_SET_BSS_SIZE(&headers,local_bss_counter );
311 * Crawl the symbol chain.
313 * For each symbol whose value depends on a frag, take the address of
314 * that frag and subsume it into the value of the symbol.
315 * After this, there is just one way to lookup a symbol value.
316 * Values are left in their final state for object file emission.
317 * We adjust the values of 'L' local symbols, even if we do
318 * not intend to emit them to the object file, because their values
319 * are needed for fix-ups.
321 * Unless we saw a -L flag, remove all symbols that begin with 'L'
322 * from the symbol chain. (They are still pointed to by the fixes.)
324 * Count the remaining symbols.
325 * Assign a symbol number to each symbol.
326 * Count the number of string-table chars we will emit.
327 * Put this info into the headers as appropriate.
330 know(zero_address_frag.fr_address == 0);
331 string_byte_count = sizeof(string_byte_count);
333 obj_crawl_symbol_chain(&headers);
335 if (string_byte_count == sizeof(string_byte_count)) {
336 string_byte_count = 0;
337 } /* if no strings, then no count. */
339 H_SET_STRING_SIZE(&headers, string_byte_count);
342 * Addresses of frags now reflect addresses we use in the object file.
343 * Symbol values are correct.
344 * Scan the frags, converting any ".org"s and ".align"s to ".fill"s.
345 * Also converting any machine-dependent frags using md_convert_frag();
347 subseg_change(SEG_TEXT, 0);
349 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next) {
350 switch (fragP->fr_type) {
354 HANDLE_ALIGN (fragP);
356 fragP->fr_type = rs_fill;
357 know(fragP->fr_var == 1);
358 know(fragP->fr_next != NULL);
360 fragP->fr_offset = (fragP->fr_next->fr_address
368 case rs_machine_dependent:
369 md_convert_frag(&headers, fragP);
371 know((fragP->fr_next == NULL) || ((fragP->fr_next->fr_address - fragP->fr_address) == fragP->fr_fix));
374 * After md_convert_frag, we make the frag into a ".space 0".
375 * Md_convert_frag() should set up any fixSs and constants
381 #ifndef WORKING_DOT_WORD
382 case rs_broken_word: {
383 struct broken_word *lie;
384 extern md_short_jump_size;
385 extern md_long_jump_size;
387 if (fragP->fr_subtype) {
388 fragP->fr_fix+=md_short_jump_size;
389 for (lie=(struct broken_word *)(fragP->fr_symbol);lie && lie->dispfrag==fragP;lie=lie->next_broken_word)
391 fragP->fr_fix+=md_long_jump_size;
399 BAD_CASE( fragP->fr_type );
401 } /* switch (fr_type) */
403 if (!((fragP->fr_next == NULL)
405 || (fragP->fr_next == data_frag_root)
407 || ((fragP->fr_next->fr_address - fragP->fr_address)
408 == (fragP->fr_fix + (fragP->fr_offset * fragP->fr_var)))))
410 fprintf (stderr, "assertion failed: file `%s', line %d\n",
411 __FILE__, __LINE__ - 4);
414 } /* for each frag. */
416 #ifndef WORKING_DOT_WORD
418 struct broken_word *lie;
419 struct broken_word **prevP;
421 prevP= &broken_words;
422 for (lie=broken_words; lie; lie=lie->next_broken_word)
425 fix_new_ns32k(lie->frag,
426 lie->word_goes_here - lie->frag->fr_literal,
433 # if defined(TC_SPARC) || defined(TC_A29K) || defined(NEED_FX_R_TYPE)
434 fix_new( lie->frag, lie->word_goes_here - lie->frag->fr_literal,
436 lie->sub, lie->addnum,
439 fix_new( lie->frag, lie->word_goes_here - lie->frag->fr_literal,
441 lie->sub, lie->addnum,
444 # endif /* tc_sparc|tc_a29k|need_fx_r_type */
445 #endif /* TC_NS32K */
446 /* md_number_to_chars(lie->word_goes_here,
447 S_GET_VALUE(lie->add)
449 - S_GET_VALUE(lie->sub),
451 *prevP=lie->next_broken_word;
453 prevP= &(lie->next_broken_word);
455 for (lie=broken_words;lie;) {
456 struct broken_word *untruth;
464 extern md_short_jump_size;
465 extern md_long_jump_size;
469 /* Find out how many broken_words go here */
471 for (untruth=lie;untruth && untruth->dispfrag==fragP;untruth=untruth->next_broken_word)
472 if (untruth->added==1)
475 table_ptr=lie->dispfrag->fr_opcode;
476 table_addr=lie->dispfrag->fr_address+(table_ptr - lie->dispfrag->fr_literal);
477 /* Create the jump around the long jumps */
478 /* This is a short jump from table_ptr+0 to table_ptr+n*long_jump_size */
479 from_addr=table_addr;
480 to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
481 md_create_short_jump(table_ptr, from_addr, to_addr, lie->dispfrag, lie->add);
482 table_ptr+=md_short_jump_size;
483 table_addr+=md_short_jump_size;
485 for (m=0;lie && lie->dispfrag==fragP;m++,lie=lie->next_broken_word) {
488 /* Patch the jump table */
489 /* This is the offset from ??? to table_ptr+0 */
491 - S_GET_VALUE(lie->sub);
492 md_number_to_chars(lie->word_goes_here,to_addr,2);
493 for (untruth=lie->next_broken_word;untruth && untruth->dispfrag==fragP;untruth=untruth->next_broken_word) {
494 if (untruth->use_jump==lie)
495 md_number_to_chars(untruth->word_goes_here,to_addr,2);
498 /* Install the long jump */
499 /* this is a long jump from table_ptr+0 to the final target */
500 from_addr=table_addr;
501 to_addr=S_GET_VALUE(lie->add) + lie->addnum;
502 md_create_long_jump(table_ptr,from_addr,to_addr,lie->dispfrag,lie->add);
503 table_ptr+=md_long_jump_size;
504 table_addr+=md_long_jump_size;
508 #endif /* not WORKING_DOT_WORD */
513 * Scan every FixS performing fixups. We had to wait until now to do
514 * this because md_convert_frag() may have made some fixSs.
518 subseg_change (SEG_TEXT, 0);
519 trsize = md_reloc_size * fixup_segment (text_fix_root,
521 subseg_change (SEG_DATA, 0);
522 drsize = md_reloc_size * fixup_segment (data_fix_root,
524 H_SET_RELOCATION_SIZE (&headers, trsize, drsize);
526 /* FIXME move this stuff into the pre-write-hook */
527 H_SET_MAGIC_NUMBER(&headers, magic_number_for_object_file);
528 H_SET_ENTRY_POINT(&headers, 0);
530 obj_pre_write_hook(&headers); /* extra coff stuff */
531 if ((had_warnings() && flagseen['Z'])
532 || had_errors() > 0) {
534 as_warn("%d error%s, %d warning%s, generating bad object file.\n",
535 had_errors(), had_errors() == 1 ? "" : "s",
536 had_warnings(), had_warnings() == 1 ? "" : "s");
538 as_fatal("%d error%s, %d warning%s, no object file generated.\n",
539 had_errors(), had_errors() == 1 ? "" : "s",
540 had_warnings(), had_warnings() == 1 ? "" : "s");
541 } /* on want output */
542 } /* on error condition */
544 object_file_size = H_GET_FILE_SIZE(&headers);
545 next_object_file_charP = the_object_file = xmalloc(object_file_size);
547 output_file_create(out_file_name);
549 obj_header_append(&next_object_file_charP, &headers);
551 know((next_object_file_charP - the_object_file) == H_GET_HEADER_SIZE(&headers));
556 for (fragP = text_frag_root; fragP; fragP = fragP->fr_next) {
558 register char *fill_literal;
559 register long fill_size;
561 know(fragP->fr_type == rs_fill);
562 append(&next_object_file_charP, fragP->fr_literal, (unsigned long) fragP->fr_fix);
563 fill_literal = fragP->fr_literal + fragP->fr_fix;
564 fill_size = fragP->fr_var;
565 know(fragP->fr_offset >= 0);
567 for (count = fragP->fr_offset; count; count--) {
568 append(&next_object_file_charP, fill_literal, (unsigned long) fill_size);
571 } /* for each code frag. */
573 know((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE(&headers) + H_GET_TEXT_SIZE(&headers) + H_GET_DATA_SIZE(&headers)));
578 obj_emit_relocations(&next_object_file_charP, text_fix_root, (relax_addressT)0);
579 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)));
581 /* Make addresses in data relocation directives relative to beginning of
582 * first data fragment, not end of last text fragment: alignment of the
583 * start of the data segment may place a gap between the segments.
585 obj_emit_relocations(&next_object_file_charP, data_fix_root, data0_frchainP->frch_root->fr_address);
587 obj_emit_relocations(&next_object_file_charP, data_fix_root, text_last_frag->fr_address);
590 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)));
593 * Emit line number entries.
595 OBJ_EMIT_LINENO(&next_object_file_charP, lineno_rootP, the_object_file);
596 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)));
601 obj_emit_symbols(&next_object_file_charP, symbol_rootP);
602 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)));
608 if (string_byte_count > 0) {
609 obj_emit_strings(&next_object_file_charP);
610 } /* only if we have a string table */
612 /* 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)));
614 /* know(next_object_file_charP == the_object_file + object_file_size);*/
617 bfd_seek(stdoutput, 0, 0);
618 bfd_write(the_object_file, 1, object_file_size, stdoutput);
621 /* Write the data to the file */
622 output_file_append(the_object_file,object_file_size,out_file_name);
625 output_file_close(out_file_name);
626 } /* non vms output */
629 * Now do the VMS-dependent part of writing the object file
631 VMS_write_object_file(text_siz, data_siz, text_frag_root, data_frag_root);
633 } /* write_object_file() */
640 * Now we have a segment, not a crowd of sub-segments, we can make fr_address
645 * After this, all frags in this segment have addresses that are correct
646 * within the segment. Since segments live in different file addresses,
647 * these frag addresses may not be the same as final object-file addresses.
652 void relax_segment(segment_frag_root, segment)
653 struct frag * segment_frag_root;
654 segT segment; /* SEG_DATA or SEG_TEXT */
656 register struct frag * fragP;
657 register relax_addressT address;
658 #ifndef MANY_SEGMENTS
659 know(segment == SEG_DATA || segment == SEG_TEXT || segment == SEG_BSS);
661 /* In case md_estimate_size_before_relax() wants to make fixSs. */
662 subseg_change(segment, 0);
665 * For each frag in segment: count and store (a 1st guess of)
669 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next) {
670 fragP->fr_address = address;
671 address += fragP->fr_fix;
673 switch (fragP->fr_type) {
675 address += fragP->fr_offset * fragP->fr_var ;
679 address += relax_align(address, fragP->fr_offset);
684 * Assume .org is nugatory. It will grow with 1st
689 case rs_machine_dependent:
690 address += md_estimate_size_before_relax(fragP, segment);
693 #ifndef WORKING_DOT_WORD
694 /* Broken words don't concern us yet */
700 BAD_CASE(fragP->fr_type);
702 } /* switch(fr_type) */
703 } /* for each frag in the segment */
709 register long stretch; /* May be any size, 0 or negative. */
710 /* Cumulative number of addresses we have */
711 /* relaxed this pass. */
712 /* We may have relaxed more than one address. */
713 register long stretched; /* Have we stretched on this pass? */
714 /* This is 'cuz stretch may be zero, when,
715 in fact some piece of code grew, and
716 another shrank. If a branch instruction
717 doesn't fit anymore, we could be scrod */
720 stretch = stretched = 0;
721 for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next) {
722 register long growth = 0;
723 register unsigned long was_address;
724 /* register long var; */
725 register long offset;
726 register symbolS *symbolP;
727 register long target;
731 was_address = fragP->fr_address;
732 address = fragP->fr_address += stretch;
733 symbolP = fragP->fr_symbol;
734 offset = fragP->fr_offset;
735 /* var = fragP->fr_var; */
737 switch (fragP->fr_type) {
738 case rs_fill: /* .fill never relaxes. */
742 #ifndef WORKING_DOT_WORD
743 /* JF: This is RMS's idea. I do *NOT* want to be blamed
744 for it I do not want to write it. I do not want to have
745 anything to do with it. This is not the proper way to
746 implement this misfeature. */
747 case rs_broken_word: {
748 struct broken_word *lie;
749 struct broken_word *untruth;
750 extern int md_short_jump_size;
751 extern int md_long_jump_size;
753 /* Yes this is ugly (storing the broken_word pointer
754 in the symbol slot). Still, this whole chunk of
755 code is ugly, and I don't feel like doing anything
756 about it. Think of it as stubbornness in action */
758 for (lie=(struct broken_word *)(fragP->fr_symbol);
759 lie && lie->dispfrag==fragP;
760 lie=lie->next_broken_word) {
765 offset= lie->add->sy_frag->fr_address+ S_GET_VALUE(lie->add) + lie->addnum -
766 (lie->sub->sy_frag->fr_address+ S_GET_VALUE(lie->sub));
767 if (offset<=-32768 || offset>=32767) {
769 as_warn(".word %s-%s+%ld didn't fit",
770 S_GET_NAME(lie->add),
771 S_GET_NAME(lie->sub),
774 if (fragP->fr_subtype==0) {
776 growth+=md_short_jump_size;
778 for (untruth=lie->next_broken_word;untruth && untruth->dispfrag==lie->dispfrag;untruth=untruth->next_broken_word)
779 if ((untruth->add->sy_frag == lie->add->sy_frag)
780 && S_GET_VALUE(untruth->add) == S_GET_VALUE(lie->add)) {
782 untruth->use_jump=lie;
784 growth+=md_long_jump_size;
789 } /* case rs_broken_word */
792 growth = relax_align((relax_addressT) (address + fragP->fr_fix), offset)
793 - relax_align((relax_addressT) (was_address + fragP->fr_fix), offset);
802 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);
803 know(symbolP->sy_frag);
804 know(!(S_GET_SEGMENT(symbolP) == SEG_ABSOLUTE) || (symbolP->sy_frag == &zero_address_frag));
806 target += S_GET_VALUE(symbolP)
807 + symbolP->sy_frag->fr_address;
808 } /* if we have a symbol */
810 know(fragP->fr_next);
811 after = fragP->fr_next->fr_address;
812 growth = ((target - after ) > 0) ? (target - after) : 0;
813 /* Growth may be -ve, but variable part */
814 /* of frag cannot have < 0 chars. */
815 /* That is, we can't .org backwards. */
817 growth -= stretch; /* This is an absolute growth factor */
820 case rs_machine_dependent: {
821 register const relax_typeS * this_type;
822 register const relax_typeS * start_type;
823 register relax_substateT next_state;
824 register relax_substateT this_state;
826 start_type = this_type = md_relax_table + (this_state = fragP->fr_subtype);
830 #ifndef MANY_SEGMENTS
831 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));
833 know(symbolP->sy_frag);
834 know(!(S_GET_SEGMENT(symbolP) == SEG_ABSOLUTE) || symbolP->sy_frag==&zero_address_frag );
837 + symbolP->sy_frag->fr_address;
839 /* If frag has yet to be reached on this pass,
840 assume it will move by STRETCH just as we did.
841 If this is not so, it will be because some frag
842 between grows, and that will force another pass. */
844 /* JF was just address */
845 /* JF also added is_dnrange hack */
846 /* There's gotta be a better/faster/etc way
849 because I ran into a zero-length frag (fr_fix=0)
850 which was created when the obstack needed a new
851 chunk JUST AFTER the opcode of a branch. Since
852 fr_fix is zero, fr_address of this frag is the same
853 as fr_address of the next frag. This
854 zero-length frag was variable and jumped to .+2
855 (in the next frag), but since the > comparison
856 below failed (the two were =, not >), "stretch"
857 was not added to the target. Stretch was 178, so
858 the offset appeared to be .-176 instead, which did
859 not fit into a byte branch, so the assembler
860 relaxed the branch to a word. This didn't compare
861 with what happened when the same source file was
862 assembled on other machines, which is how I found it.
863 You might want to think about what other places have
864 trouble with zero length frags... */
866 if (symbolP->sy_frag->fr_address >= was_address
867 && is_dnrange(fragP,symbolP->sy_frag)) {
871 } /* if there's a symbol attached */
873 aim = target - address - fragP->fr_fix;
874 /* The displacement is affected by the instruction size
875 * for the 32k architecture. I think we ought to be able
876 * to add fragP->fr_pcrel_adjust in all cases (it should be
877 * zero if not used), but just in case it breaks something
878 * else we'll put this inside #ifdef NS32K ... #endif
881 aim += fragP->fr_pcrel_adjust;
882 #endif /* TC_NS32K */
885 /* Look backwards. */
886 for (next_state = this_type->rlx_more; next_state; ) {
887 if (aim >= this_type->rlx_backward) {
889 } else { /* Grow to next state. */
890 this_type = md_relax_table + (this_state = next_state);
891 next_state = this_type->rlx_more;
896 /* JF these next few lines of code are for the mc68020 which can't handle short
897 offsets of zero in branch instructions. What a kludge! */
898 if (aim==0 && this_state==(1<<2+0)) { /* FOO hard encoded from m.c */
899 aim=this_type->rlx_forward+1; /* Force relaxation into word mode */
902 #ifdef M68K_AIM_KLUDGE
903 M68K_AIM_KLUDGE(aim, this_state, this_type);
905 /* JF end of 68020 code */
907 for (next_state = this_type->rlx_more; next_state; ) {
908 if (aim <= this_type->rlx_forward) {
910 } else { /* Grow to next state. */
911 this_type = md_relax_table + (this_state = next_state);
912 next_state = this_type->rlx_more;
917 if ((growth = this_type->rlx_length - start_type->rlx_length) != 0)
918 fragP->fr_subtype = this_state;
921 } /* case rs_machine_dependent */
924 BAD_CASE( fragP->fr_type );
931 } /* For each frag in the segment. */
932 } while (stretched); /* Until nothing further to relax. */
936 * We now have valid fr_address'es for each frag.
940 * All fr_address's are correct, relative to their own segment.
941 * We have made all the fixS we will ever make.
943 } /* relax_segment() */
946 * Relax_align. Advance location counter to next address that has 'alignment'
947 * lowest order bits all 0s.
950 /* How many addresses does the .align take? */
951 static relax_addressT
952 relax_align(address, alignment)
953 register relax_addressT address; /* Address now. */
954 register long alignment; /* Alignment (binary). */
957 relax_addressT new_address;
959 mask = ~ ( (~0) << alignment );
960 new_address = (address + mask) & (~ mask);
962 /* We must provide lots of padding, so the linker can discard it
963 when needed. The linker will not add extra space, ever. */
964 new_address += (1 << alignment);
965 return (new_address - address);
966 } /* relax_align() */
970 Go through all the fixS's in a segment and see which ones can be
971 handled now. (These consist of fixS where we have since discovered
972 the value of a symbol, or the address of the frag involved.)
973 For each one, call md_apply_fix to put the fix into the frag data.
975 Result is a count of how many relocation structs will be needed to
976 handle the remaining fixS's that we couldn't completely handle here.
977 These will be output later by emit_relocations(). */
980 fixup_segment(fixP, this_segment_type)
982 segT this_segment_type; /* N_TYPE bits for segment. */
984 register long seg_reloc_count;
985 register symbolS *add_symbolP;
986 register symbolS *sub_symbolP;
987 register long add_number;
989 register char *place;
992 register fragS *fragP;
993 register segT add_symbol_segment = SEG_ABSOLUTE;
995 /* FIXME: remove this line */ /* fixS *orig = fixP; */
998 /* If the linker is doing the relaxing, we must not do any fixups */
1000 for ( ; fixP ; fixP = fixP->fx_next) {
1006 for ( ; fixP; fixP = fixP->fx_next) {
1007 fragP = fixP->fx_frag;
1009 where = fixP->fx_where;
1010 place = fragP->fr_literal + where;
1011 size = fixP->fx_size;
1012 add_symbolP = fixP->fx_addsy;
1014 if (fixP->fx_callj && TC_S_IS_CALLNAME(add_symbolP)) {
1015 /* Relocation should be done via the
1016 associated 'bal' entry point
1019 if (!TC_S_IS_BALNAME(tc_get_bal_of_call(add_symbolP))) {
1020 as_bad("No 'bal' entry point for leafproc %s",
1021 S_GET_NAME(add_symbolP));
1024 fixP->fx_addsy = add_symbolP = tc_get_bal_of_call(add_symbolP);
1025 } /* callj relocation */
1027 sub_symbolP = fixP->fx_subsy;
1028 add_number = fixP->fx_offset;
1029 pcrel = fixP->fx_pcrel;
1032 add_symbol_segment = S_GET_SEGMENT(add_symbolP);
1033 } /* if there is an addend */
1038 if (S_GET_SEGMENT(sub_symbolP) != SEG_ABSOLUTE) {
1039 as_bad("Negative of non-absolute symbol %s", S_GET_NAME(sub_symbolP));
1040 } /* not absolute */
1042 add_number -= S_GET_VALUE(sub_symbolP);
1044 /* if sub_symbol is in the same segment that add_symbol
1045 and add_symbol is either in DATA, TEXT, BSS or ABSOLUTE */
1046 } else if ((S_GET_SEGMENT(sub_symbolP) == add_symbol_segment)
1047 && (SEG_NORMAL(add_symbol_segment)
1048 || (add_symbol_segment == SEG_ABSOLUTE))) {
1049 /* Difference of 2 symbols from same segment. */
1050 /* Can't make difference of 2 undefineds: 'value' means */
1051 /* something different for N_UNDF. */
1053 /* Makes no sense to use the difference of 2 arbitrary symbols
1054 * as the target of a call instruction.
1056 if (fixP->fx_callj) {
1057 as_bad("callj to difference of 2 symbols");
1059 #endif /* TC_I960 */
1060 add_number += S_GET_VALUE(add_symbolP) -
1061 S_GET_VALUE(sub_symbolP);
1064 fixP->fx_addsy = NULL;
1066 /* Different segments in subtraction. */
1067 know(!(S_IS_EXTERNAL(sub_symbolP) && (S_GET_SEGMENT(sub_symbolP) == SEG_ABSOLUTE)));
1069 if ((S_GET_SEGMENT(sub_symbolP) == SEG_ABSOLUTE)) {
1070 add_number -= S_GET_VALUE(sub_symbolP);
1072 as_bad("Can't emit reloc {- %s-seg symbol \"%s\"} @ file address %d.",
1073 segment_name(S_GET_SEGMENT(sub_symbolP)),
1074 S_GET_NAME(sub_symbolP), fragP->fr_address + where);
1077 } /* if sub_symbolP */
1080 if (add_symbol_segment == this_segment_type && pcrel) {
1082 * This fixup was made when the symbol's segment was
1083 * SEG_UNKNOWN, but it is now in the local segment.
1084 * So we know how to do the address without relocation.
1087 /* reloc_callj() may replace a 'call' with a 'calls' or a 'bal',
1088 * in which cases it modifies *fixP as appropriate. In the case
1089 * of a 'calls', no further work is required, and *fixP has been
1090 * set up to make the rest of the code below a no-op.
1093 #endif /* TC_I960 */
1095 add_number += S_GET_VALUE(add_symbolP);
1096 add_number -= md_pcrel_from (fixP);
1097 pcrel = 0; /* Lie. Don't want further pcrel processing. */
1098 fixP->fx_addsy = NULL; /* No relocations please. */
1100 switch (add_symbol_segment) {
1103 reloc_callj(fixP); /* See comment about reloc_callj() above*/
1104 #endif /* TC_I960 */
1105 add_number += S_GET_VALUE(add_symbolP);
1106 fixP->fx_addsy = NULL;
1111 add_number += S_GET_VALUE(add_symbolP);
1116 if ((int)fixP->fx_bit_fixP == 13) {
1117 /* This is a COBR instruction. They have only a
1118 * 13-bit displacement and are only to be used
1119 * for local branches: flag as error, don't generate
1122 as_bad("can't use COBR format with external label");
1123 fixP->fx_addsy = NULL; /* No relocations please. */
1126 #endif /* TC_I960 */
1130 if (S_IS_COMMON(add_symbolP))
1131 add_number += S_GET_VALUE(add_symbolP);
1132 #endif /* TE_I386AIX */
1133 #endif /* OBJ_COFF */
1139 } /* switch on symbol seg */
1140 } /* if not in local seg */
1141 } /* if there was a + symbol */
1144 add_number -= md_pcrel_from(fixP);
1145 if (add_symbolP == 0) {
1146 fixP->fx_addsy = & abs_symbol;
1148 } /* if there's an add_symbol */
1151 if (!fixP->fx_bit_fixP) {
1153 (add_number& ~0xFF) && (add_number&~0xFF!=(-1&~0xFF))) ||
1155 (add_number& ~0xFFFF) && (add_number&~0xFFFF!=(-1&~0xFFFF)))) {
1156 as_bad("Value of %d too large for field of %d bytes at 0x%x",
1157 add_number, size, fragP->fr_address + where);
1158 } /* generic error checking */
1159 } /* not a bit fix */
1161 md_apply_fix(fixP, add_number);
1162 } /* For each fixS in this segment. */
1169 /* two relocs per callj under coff. */
1170 for (fixP = topP; fixP; fixP = fixP->fx_next) {
1171 if (fixP->fx_callj && fixP->fx_addsy != 0) {
1173 } /* if callj and not already fixed. */
1174 } /* for each fix */
1176 #endif /* TC_I960 */
1178 #endif /* OBJ_COFF */
1179 return(seg_reloc_count);
1180 } /* fixup_segment() */
1183 static int is_dnrange(f1,f2)
1188 if (f1->fr_next==f2)
1193 } /* is_dnrange() */
1195 /* Append a string onto another string, bumping the pointer along. */
1197 append (charPP, fromP, length)
1200 unsigned long length;
1202 if (length) { /* Don't trust memcpy() of 0 chars. */
1203 memcpy(*charPP, fromP, (int) length);
1208 int section_alignment[SEG_MAXIMUM_ORDINAL];
1211 * This routine records the largest alignment seen for each segment.
1212 * If the beginning of the segment is aligned on the worst-case
1213 * boundary, all of the other alignments within it will work. At
1214 * least one object format really uses this info.
1216 void record_alignment(seg, align)
1217 segT seg; /* Segment to which alignment pertains */
1218 int align; /* Alignment, as a power of 2
1219 * (e.g., 1 => 2-byte boundary, 2 => 4-byte boundary, etc.)
1223 if ( align > section_alignment[(int) seg] ){
1224 section_alignment[(int) seg] = align;
1225 } /* if highest yet */
1228 } /* record_alignment() */
1237 /* end of write.c */