darling-gdb/gas/write.c

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/* write.c - emit .o file
Copyright (C) 1986, 1987, 1990, 1991, 1992 Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
GAS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GAS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GAS; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
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/* This thing should be set up to do byteordering correctly. But... */
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#include "as.h"
#include "subsegs.h"
#include "obstack.h"
#include "output-file.h"
/* The NOP_OPCODE is for the alignment fill value.
* fill it a nop instruction so that the disassembler does not choke
* on it
*/
#ifndef NOP_OPCODE
#define NOP_OPCODE 0x00
#endif
#ifndef MANY_SEGMENTS
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struct frag *text_frag_root;
struct frag *data_frag_root;
struct frag *bss_frag_root;
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struct frag *text_last_frag; /* Last frag in segment. */
struct frag *data_last_frag; /* Last frag in segment. */
static struct frag *bss_last_frag; /* Last frag in segment. */
#endif
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static object_headers headers;
long string_byte_count;
static char *the_object_file;
char *next_object_file_charP; /* Tracks object file bytes. */
int magic_number_for_object_file = DEFAULT_MAGIC_NUMBER_FOR_OBJECT_FILE;
static int is_dnrange PARAMS ((struct frag * f1, struct frag * f2));
static long fixup_segment PARAMS ((fixS * fixP, segT this_segment_type));
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static relax_addressT relax_align PARAMS ((relax_addressT addr, long align));
void relax_segment PARAMS ((struct frag * seg_frag_root, segT seg_type));
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/*
* fix_new()
*
* Create a fixS in obstack 'notes'.
*/
fixS *
fix_new (frag, where, size, add_symbol, sub_symbol, offset, pcrel, r_type)
fragS *frag; /* Which frag? */
int where; /* Where in that frag? */
short int size; /* 1, 2, or 4 usually. */
symbolS *add_symbol; /* X_add_symbol. */
symbolS *sub_symbol; /* X_subtract_symbol. */
long offset; /* X_add_number. */
int pcrel; /* TRUE if PC-relative relocation. */
int r_type; /* Relocation type */
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{
fixS *fixP;
fixP = (fixS *) obstack_alloc (&notes, sizeof (fixS));
fixP->fx_frag = frag;
fixP->fx_where = where;
fixP->fx_size = size;
fixP->fx_addsy = add_symbol;
fixP->fx_subsy = sub_symbol;
fixP->fx_offset = offset;
fixP->fx_pcrel = pcrel;
#if defined(TC_SPARC) || defined(TC_A29K) || defined( NEED_FX_R_TYPE)
fixP->fx_r_type = r_type;
#endif
/* JF these 'cuz of the NS32K stuff */
fixP->fx_im_disp = 0;
fixP->fx_pcrel_adjust = 0;
fixP->fx_bsr = 0;
fixP->fx_bit_fixP = 0;
/* usually, we want relocs sorted numerically, but while
comparing to older versions of gas that have relocs
reverse sorted, it is convenient to have this compile
time option. xoxorich. */
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#ifdef REVERSE_SORT_RELOCS
fixP->fx_next = *seg_fix_rootP;
*seg_fix_rootP = fixP;
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#else /* REVERSE_SORT_RELOCS */
fixP->fx_next = NULL;
if (*seg_fix_tailP)
(*seg_fix_tailP)->fx_next = fixP;
else
*seg_fix_rootP = fixP;
*seg_fix_tailP = fixP;
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#endif /* REVERSE_SORT_RELOCS */
fixP->fx_callj = 0;
return (fixP);
} /* fix_new() */
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#ifndef BFD
void
remove_subsegs (head, seg, root, last)
frchainS *head;
int seg;
fragS **root;
fragS **last;
{
fragS dummy;
fragS *prev_frag = &dummy;
*root = head->frch_root;
while (head && head->frch_seg == seg)
{
prev_frag->fr_next = head->frch_root;
prev_frag = head->frch_last;
head = head->frch_next;
}
*last = prev_frag;
prev_frag->fr_next = 0;
}
void
write_object_file ()
{
register struct frchain *frchainP; /* Track along all frchains. */
register fragS *fragP; /* Track along all frags. */
register struct frchain *next_frchainP;
register fragS **prev_fragPP;
unsigned int data_siz;
long object_file_size;
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#ifdef VMS
/*
* Under VMS we try to be compatible with VAX-11 "C". Thus, we
* call a routine to check for the definition of the procedure
* "_main", and if so -- fix it up so that it can be program
* entry point.
*/
VMS_Check_For_Main ();
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#endif /* VMS */
/*
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* After every sub-segment, we fake an ".align ...". This conforms to
* BSD4.2 brane-damage. We then fake ".fill 0" because that is the
* kind of frag that requires least thought. ".align" frags like to
* have a following frag since that makes calculating their intended
* length trivial.
*/
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#define SUB_SEGMENT_ALIGN (2)
for (frchainP = frchain_root; frchainP; frchainP = frchainP->frch_next)
{
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#ifdef VMS
/*
* Under VAX/VMS, the linker (and PSECT specifications)
* take care of correctly aligning the segments.
* Doing the alignment here (on initialized data) can
* mess up the calculation of global data PSECT sizes.
*/
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#undef SUB_SEGMENT_ALIGN
#define SUB_SEGMENT_ALIGN ((frchainP->frch_seg != SEG_DATA) ? 2 : 0)
#endif /* VMS */
subseg_new (frchainP->frch_seg, frchainP->frch_subseg);
frag_align (SUB_SEGMENT_ALIGN, NOP_OPCODE);
/* frag_align will have left a new frag. */
/* Use this last frag for an empty ".fill". */
/*
* For this segment ...
* Create a last frag. Do not leave a "being filled in frag".
*/
frag_wane (frag_now);
frag_now->fr_fix = 0;
know (frag_now->fr_next == NULL);
/* know( frags . obstack_c_base == frags . obstack_c_next_free ); */
/* Above shows we haven't left a half-completed object on obstack. */
} /* walk the frag chain */
/*
* From now on, we don't care about sub-segments.
* Build one frag chain for each segment. Linked thru fr_next.
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* We know that there is at least 1 text frchain & at least 1 data
* frchain.
*/
remove_subsegs (frchain_root, SEG_TEXT, &text_frag_root, &text_last_frag);
remove_subsegs (data0_frchainP, SEG_DATA, &data_frag_root, &data_last_frag);
remove_subsegs (bss0_frchainP, SEG_BSS, &bss_frag_root, &bss_last_frag);
/*
* We have two segments. If user gave -R flag, then we must put the
* data frags into the text segment. Do this before relaxing so
* we know to take advantage of -R and make shorter addresses.
*/
#ifndef OBJ_AOUT
if (flagseen['R'])
{
fixS *tmp;
text_last_frag->fr_next = data_frag_root;
text_last_frag = data_last_frag;
data_last_frag = NULL;
data_frag_root = NULL;
if (text_fix_root)
{
for (tmp = text_fix_root; tmp->fx_next; tmp = tmp->fx_next);;
tmp->fx_next = data_fix_root;
text_fix_tail = data_fix_tail;
}
else
text_fix_root = data_fix_root;
data_fix_root = NULL;
}
#endif
relax_segment (text_frag_root, SEG_TEXT);
relax_segment (data_frag_root, SEG_DATA);
relax_segment (bss_frag_root, SEG_BSS);
/*
* Now the addresses of frags are correct within the segment.
*/
know (text_last_frag->fr_type == rs_fill && text_last_frag->fr_offset == 0);
H_SET_TEXT_SIZE (&headers, text_last_frag->fr_address);
text_last_frag->fr_address = H_GET_TEXT_SIZE (&headers);
/*
* Join the 2 segments into 1 huge segment.
* To do this, re-compute every rn_address in the SEG_DATA frags.
* Then join the data frags after the text frags.
*
* Determine a_data [length of data segment].
*/
if (data_frag_root)
{
register relax_addressT slide;
know ((text_last_frag->fr_type == rs_fill) && (text_last_frag->fr_offset == 0));
H_SET_DATA_SIZE (&headers, data_last_frag->fr_address);
data_last_frag->fr_address = H_GET_DATA_SIZE (&headers);
slide = H_GET_TEXT_SIZE (&headers); /* & in file of the data segment. */
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#ifdef OBJ_BOUT
#define RoundUp(N,S) (((N)+(S)-1)&-(S))
/* For b.out: If the data section has a strict alignment
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requirement, its load address in the .o file will be
rounded up from the size of the text section. These
two values are *not* the same! Similarly for the bss
section.... */
slide = RoundUp (slide, 1 << section_alignment[SEG_DATA]);
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#endif
for (fragP = data_frag_root; fragP; fragP = fragP->fr_next)
{
fragP->fr_address += slide;
} /* for each data frag */
know (text_last_frag != 0);
text_last_frag->fr_next = data_frag_root;
}
else
{
H_SET_DATA_SIZE (&headers, 0);
data_siz = 0;
}
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#ifdef OBJ_BOUT
/* See above comments on b.out data section address. */
{
long bss_vma;
if (data_last_frag == 0)
bss_vma = H_GET_TEXT_SIZE (&headers);
else
bss_vma = data_last_frag->fr_address;
bss_vma = RoundUp (bss_vma, 1 << section_alignment[SEG_BSS]);
bss_address_frag.fr_address = bss_vma;
}
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#else
bss_address_frag.fr_address = (H_GET_TEXT_SIZE (&headers) +
H_GET_DATA_SIZE (&headers));
/* Slide all the frags */
if (bss_frag_root)
{
relax_addressT slide = bss_address_frag.fr_address + local_bss_counter;
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for (fragP = bss_frag_root; fragP; fragP = fragP->fr_next)
{
fragP->fr_address += slide;
} /* for each bss frag */
}
#endif
if (bss_last_frag)
{
local_bss_counter += bss_last_frag->fr_address - bss_frag_root->fr_address;
}
H_SET_BSS_SIZE (&headers, local_bss_counter);
/*
*
* Crawl the symbol chain.
*
* For each symbol whose value depends on a frag, take the address of
* that frag and subsume it into the value of the symbol.
* After this, there is just one way to lookup a symbol value.
* Values are left in their final state for object file emission.
* We adjust the values of 'L' local symbols, even if we do
* not intend to emit them to the object file, because their values
* are needed for fix-ups.
*
* Unless we saw a -L flag, remove all symbols that begin with 'L'
* from the symbol chain. (They are still pointed to by the fixes.)
*
* Count the remaining symbols.
* Assign a symbol number to each symbol.
* Count the number of string-table chars we will emit.
* Put this info into the headers as appropriate.
*
*/
know (zero_address_frag.fr_address == 0);
string_byte_count = sizeof (string_byte_count);
obj_crawl_symbol_chain (&headers);
if (string_byte_count == sizeof (string_byte_count))
{
string_byte_count = 0;
} /* if no strings, then no count. */
H_SET_STRING_SIZE (&headers, string_byte_count);
/*
* Addresses of frags now reflect addresses we use in the object file.
* Symbol values are correct.
* Scan the frags, converting any ".org"s and ".align"s to ".fill"s.
* Also converting any machine-dependent frags using md_convert_frag();
*/
subseg_change (SEG_TEXT, 0);
for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
{
switch (fragP->fr_type)
{
case rs_align:
case rs_org:
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#ifdef HANDLE_ALIGN
HANDLE_ALIGN (fragP);
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#endif
fragP->fr_type = rs_fill;
know (fragP->fr_var == 1);
know (fragP->fr_next != NULL);
fragP->fr_offset = (fragP->fr_next->fr_address
- fragP->fr_address
- fragP->fr_fix);
break;
case rs_fill:
break;
case rs_machine_dependent:
md_convert_frag (&headers, fragP);
know ((fragP->fr_next == NULL) || ((fragP->fr_next->fr_address - fragP->fr_address) == fragP->fr_fix));
/*
* After md_convert_frag, we make the frag into a ".space 0".
* Md_convert_frag() should set up any fixSs and constants
* required.
*/
frag_wane (fragP);
break;
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#ifndef WORKING_DOT_WORD
case rs_broken_word:
{
struct broken_word *lie;
extern md_short_jump_size;
extern md_long_jump_size;
if (fragP->fr_subtype)
{
fragP->fr_fix += md_short_jump_size;
for (lie = (struct broken_word *) (fragP->fr_symbol); lie && lie->dispfrag == fragP; lie = lie->next_broken_word)
if (lie->added == 1)
fragP->fr_fix += md_long_jump_size;
}
frag_wane (fragP);
}
break;
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#endif
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default:
BAD_CASE (fragP->fr_type);
break;
} /* switch (fr_type) */
if (!((fragP->fr_next == NULL)
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#ifdef OBJ_BOUT
|| (fragP->fr_next == data_frag_root)
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#endif
|| ((fragP->fr_next->fr_address - fragP->fr_address)
== (fragP->fr_fix + (fragP->fr_offset * fragP->fr_var)))))
{
fprintf (stderr, "assertion failed: file `%s', line %d\n",
__FILE__, __LINE__ - 4);
exit (1);
}
} /* for each frag. */
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#ifndef WORKING_DOT_WORD
{
struct broken_word *lie;
struct broken_word **prevP;
prevP = &broken_words;
for (lie = broken_words; lie; lie = lie->next_broken_word)
if (!lie->added)
{
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#ifdef TC_NS32K
fix_new_ns32k (lie->frag,
lie->word_goes_here - lie->frag->fr_literal,
2,
lie->add,
lie->sub,
lie->addnum,
0, 0, 2, 0, 0);
#else
# if defined(TC_SPARC) || defined(TC_A29K) || defined(NEED_FX_R_TYPE)
fix_new (lie->frag, lie->word_goes_here - lie->frag->fr_literal,
2, lie->add,
lie->sub, lie->addnum,
0, NO_RELOC);
# else
fix_new (lie->frag, lie->word_goes_here - lie->frag->fr_literal,
2, lie->add,
lie->sub, lie->addnum,
0, 0);
# endif /* tc_sparc|tc_a29k|need_fx_r_type */
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#endif /* TC_NS32K */
/* md_number_to_chars(lie->word_goes_here,
S_GET_VALUE(lie->add)
+ lie->addnum
- S_GET_VALUE(lie->sub),
2); */
*prevP = lie->next_broken_word;
}
else
prevP = &(lie->next_broken_word);
for (lie = broken_words; lie;)
{
struct broken_word *untruth;
char *table_ptr;
long table_addr;
long from_addr, to_addr;
int n, m;
extern md_short_jump_size;
extern md_long_jump_size;
fragP = lie->dispfrag;
/* Find out how many broken_words go here */
n = 0;
for (untruth = lie; untruth && untruth->dispfrag == fragP; untruth = untruth->next_broken_word)
if (untruth->added == 1)
n++;
table_ptr = lie->dispfrag->fr_opcode;
table_addr = lie->dispfrag->fr_address + (table_ptr - lie->dispfrag->fr_literal);
/* Create the jump around the long jumps */
/* This is a short jump from table_ptr+0 to table_ptr+n*long_jump_size */
from_addr = table_addr;
to_addr = table_addr + md_short_jump_size + n * md_long_jump_size;
md_create_short_jump (table_ptr, from_addr, to_addr, lie->dispfrag, lie->add);
table_ptr += md_short_jump_size;
table_addr += md_short_jump_size;
for (m = 0; lie && lie->dispfrag == fragP; m++, lie = lie->next_broken_word)
{
if (lie->added == 2)
continue;
/* Patch the jump table */
/* This is the offset from ??? to table_ptr+0 */
to_addr = table_addr
- S_GET_VALUE (lie->sub);
md_number_to_chars (lie->word_goes_here, to_addr, 2);
for (untruth = lie->next_broken_word; untruth && untruth->dispfrag == fragP; untruth = untruth->next_broken_word)
{
if (untruth->use_jump == lie)
md_number_to_chars (untruth->word_goes_here, to_addr, 2);
}
/* Install the long jump */
/* this is a long jump from table_ptr+0 to the final target */
from_addr = table_addr;
to_addr = S_GET_VALUE (lie->add) + lie->addnum;
md_create_long_jump (table_ptr, from_addr, to_addr, lie->dispfrag, lie->add);
table_ptr += md_long_jump_size;
table_addr += md_long_jump_size;
}
}
}
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#endif /* not WORKING_DOT_WORD */
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#ifndef VMS
{ /* not vms */
/*
* Scan every FixS performing fixups. We had to wait until now to do
* this because md_convert_frag() may have made some fixSs.
*/
int trsize, drsize;
subseg_change (SEG_TEXT, 0);
trsize = md_reloc_size * fixup_segment (text_fix_root,
SEG_TEXT);
subseg_change (SEG_DATA, 0);
drsize = md_reloc_size * fixup_segment (data_fix_root,
SEG_DATA);
H_SET_RELOCATION_SIZE (&headers, trsize, drsize);
/* FIXME move this stuff into the pre-write-hook */
H_SET_MAGIC_NUMBER (&headers, magic_number_for_object_file);
H_SET_ENTRY_POINT (&headers, 0);
obj_pre_write_hook (&headers); /* extra coff stuff */
if ((had_warnings () && flagseen['Z'])
|| had_errors () > 0)
{
if (flagseen['Z'])
{
as_warn ("%d error%s, %d warning%s, generating bad object file.\n",
had_errors (), had_errors () == 1 ? "" : "s",
had_warnings (), had_warnings () == 1 ? "" : "s");
}
else
{
as_fatal ("%d error%s, %d warning%s, no object file generated.\n",
had_errors (), had_errors () == 1 ? "" : "s",
had_warnings (), had_warnings () == 1 ? "" : "s");
} /* on want output */
} /* on error condition */
object_file_size = H_GET_FILE_SIZE (&headers);
next_object_file_charP = the_object_file = xmalloc (object_file_size);
output_file_create (out_file_name);
obj_header_append (&next_object_file_charP, &headers);
know ((next_object_file_charP - the_object_file) == H_GET_HEADER_SIZE (&headers));
/*
* Emit code.
*/
for (fragP = text_frag_root; fragP; fragP = fragP->fr_next)
{
register long count;
register char *fill_literal;
register long fill_size;
know (fragP->fr_type == rs_fill);
append (&next_object_file_charP, fragP->fr_literal, (unsigned long) fragP->fr_fix);
fill_literal = fragP->fr_literal + fragP->fr_fix;
fill_size = fragP->fr_var;
know (fragP->fr_offset >= 0);
for (count = fragP->fr_offset; count; count--)
{
append (&next_object_file_charP, fill_literal, (unsigned long) fill_size);
} /* for each */
} /* for each code frag. */
know ((next_object_file_charP - the_object_file) == (H_GET_HEADER_SIZE (&headers) + H_GET_TEXT_SIZE (&headers) + H_GET_DATA_SIZE (&headers)));
/*
* Emit relocations.
*/
obj_emit_relocations (&next_object_file_charP, text_fix_root, (relax_addressT) 0);
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)));
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#ifdef TC_I960
/* Make addresses in data relocation directives relative to beginning of
* first data fragment, not end of last text fragment: alignment of the
* start of the data segment may place a gap between the segments.
*/
obj_emit_relocations (&next_object_file_charP, data_fix_root, data0_frchainP->frch_root->fr_address);
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#else /* TC_I960 */
obj_emit_relocations (&next_object_file_charP, data_fix_root, text_last_frag->fr_address);
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#endif /* TC_I960 */
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)));
/*
* Emit line number entries.
*/
OBJ_EMIT_LINENO (&next_object_file_charP, lineno_rootP, the_object_file);
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)));
/*
* Emit symbols.
*/
obj_emit_symbols (&next_object_file_charP, symbol_rootP);
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)));
/*
* Emit strings.
*/
if (string_byte_count > 0)
{
obj_emit_strings (&next_object_file_charP);
} /* only if we have a string table */
/* 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)));
*/
/* know(next_object_file_charP == the_object_file + object_file_size);*/
#ifdef BFD_HEADERS
bfd_seek (stdoutput, 0, 0);
bfd_write (the_object_file, 1, object_file_size, stdoutput);
#else
/* Write the data to the file */
output_file_append (the_object_file, object_file_size, out_file_name);
#endif
output_file_close (out_file_name);
} /* non vms output */
#else /* VMS */
/*
* Now do the VMS-dependent part of writing the object file
*/
VMS_write_object_file (text_siz, data_siz, text_frag_root, data_frag_root);
#endif /* VMS */
} /* write_object_file() */
#else
#endif
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/*
* relax_segment()
*
* Now we have a segment, not a crowd of sub-segments, we can make fr_address
* values.
*
* Relax the frags.
*
* After this, all frags in this segment have addresses that are correct
* within the segment. Since segments live in different file addresses,
* these frag addresses may not be the same as final object-file addresses.
*/
void
relax_segment (segment_frag_root, segment)
struct frag *segment_frag_root;
segT segment; /* SEG_DATA or SEG_TEXT */
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{
register struct frag *fragP;
register relax_addressT address;
#ifndef MANY_SEGMENTS
know (segment == SEG_DATA || segment == SEG_TEXT || segment == SEG_BSS);
#endif
/* In case md_estimate_size_before_relax() wants to make fixSs. */
subseg_change (segment, 0);
/*
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* For each frag in segment: count and store (a 1st guess of)
* fr_address.
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*/
address = 0;
for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
{
fragP->fr_address = address;
address += fragP->fr_fix;
switch (fragP->fr_type)
{
case rs_fill:
address += fragP->fr_offset * fragP->fr_var;
break;
case rs_align:
address += relax_align (address, fragP->fr_offset);
break;
case rs_org:
/*
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* Assume .org is nugatory. It will grow with 1st
* relax.
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*/
break;
case rs_machine_dependent:
address += md_estimate_size_before_relax (fragP, segment);
break;
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#ifndef WORKING_DOT_WORD
/* Broken words don't concern us yet */
case rs_broken_word:
break;
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#endif
default:
BAD_CASE (fragP->fr_type);
break;
} /* switch(fr_type) */
} /* for each frag in the segment */
/*
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* Do relax().
*/
{
register long stretch; /* May be any size, 0 or negative. */
/* Cumulative number of addresses we have */
/* relaxed this pass. */
/* We may have relaxed more than one address. */
register long stretched; /* Have we stretched on this pass? */
/* This is 'cuz stretch may be zero, when,
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in fact some piece of code grew, and
another shrank. If a branch instruction
doesn't fit anymore, we could be scrod */
do
{
stretch = stretched = 0;
for (fragP = segment_frag_root; fragP; fragP = fragP->fr_next)
{
register long growth = 0;
register unsigned long was_address;
/* register long var; */
register long offset;
register symbolS *symbolP;
register long target;
register long after;
register long aim;
was_address = fragP->fr_address;
address = fragP->fr_address += stretch;
symbolP = fragP->fr_symbol;
offset = fragP->fr_offset;
/* var = fragP->fr_var; */
switch (fragP->fr_type)
{
case rs_fill: /* .fill never relaxes. */
growth = 0;
break;
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#ifndef WORKING_DOT_WORD
/* JF: This is RMS's idea. I do *NOT* want to be blamed
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for it I do not want to write it. I do not want to have
anything to do with it. This is not the proper way to
implement this misfeature. */
case rs_broken_word:
{
struct broken_word *lie;
struct broken_word *untruth;
extern int md_short_jump_size;
extern int md_long_jump_size;
/* Yes this is ugly (storing the broken_word pointer
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in the symbol slot). Still, this whole chunk of
code is ugly, and I don't feel like doing anything
about it. Think of it as stubbornness in action */
growth = 0;
for (lie = (struct broken_word *) (fragP->fr_symbol);
lie && lie->dispfrag == fragP;
lie = lie->next_broken_word)
{
if (lie->added)
continue;
offset = lie->add->sy_frag->fr_address + S_GET_VALUE (lie->add) + lie->addnum -
(lie->sub->sy_frag->fr_address + S_GET_VALUE (lie->sub));
if (offset <= -32768 || offset >= 32767)
{
if (flagseen['K'])
as_warn (".word %s-%s+%ld didn't fit",
S_GET_NAME (lie->add),
S_GET_NAME (lie->sub),
lie->addnum);
lie->added = 1;
if (fragP->fr_subtype == 0)
{
fragP->fr_subtype++;
growth += md_short_jump_size;
}
for (untruth = lie->next_broken_word; untruth && untruth->dispfrag == lie->dispfrag; untruth = untruth->next_broken_word)
if ((untruth->add->sy_frag == lie->add->sy_frag)
&& S_GET_VALUE (untruth->add) == S_GET_VALUE (lie->add))
{
untruth->added = 2;
untruth->use_jump = lie;
}
growth += md_long_jump_size;
}
}
break;
} /* case rs_broken_word */
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#endif
case rs_align:
growth = relax_align ((relax_addressT) (address + fragP->fr_fix), offset)
- relax_align ((relax_addressT) (was_address + fragP->fr_fix), offset);
break;
case rs_org:
target = offset;
if (symbolP)
{
#ifdef MANY_SEGMENTS
#else
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);
know (symbolP->sy_frag);
know (!(S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE) || (symbolP->sy_frag == &zero_address_frag));
#endif
target += S_GET_VALUE (symbolP)
+ symbolP->sy_frag->fr_address;
} /* if we have a symbol */
know (fragP->fr_next);
after = fragP->fr_next->fr_address;
growth = ((target - after) > 0) ? (target - after) : 0;
/* Growth may be -ve, but variable part */
/* of frag cannot have < 0 chars. */
/* That is, we can't .org backwards. */
growth -= stretch; /* This is an absolute growth factor */
break;
case rs_machine_dependent:
{
register const relax_typeS *this_type;
register const relax_typeS *start_type;
register relax_substateT next_state;
register relax_substateT this_state;
start_type = this_type = md_relax_table + (this_state = fragP->fr_subtype);
target = offset;
if (symbolP)
{
#ifndef MANY_SEGMENTS
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));
#endif
know (symbolP->sy_frag);
know (!(S_GET_SEGMENT (symbolP) == SEG_ABSOLUTE) || symbolP->sy_frag == &zero_address_frag);
target +=
S_GET_VALUE (symbolP)
+ symbolP->sy_frag->fr_address;
/* If frag has yet to be reached on this pass,
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assume it will move by STRETCH just as we did.
If this is not so, it will be because some frag
between grows, and that will force another pass. */
/* JF was just address */
/* JF also added is_dnrange hack */
/* There's gotta be a better/faster/etc way
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to do this. . . */
/* gnu@cygnus.com: I changed this from > to >=
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because I ran into a zero-length frag (fr_fix=0)
which was created when the obstack needed a new
chunk JUST AFTER the opcode of a branch. Since
fr_fix is zero, fr_address of this frag is the same
as fr_address of the next frag. This
zero-length frag was variable and jumped to .+2
(in the next frag), but since the > comparison
below failed (the two were =, not >), "stretch"
was not added to the target. Stretch was 178, so
the offset appeared to be .-176 instead, which did
not fit into a byte branch, so the assembler
relaxed the branch to a word. This didn't compare
with what happened when the same source file was
assembled on other machines, which is how I found it.
You might want to think about what other places have
trouble with zero length frags... */
if (symbolP->sy_frag->fr_address >= was_address
&& is_dnrange (fragP, symbolP->sy_frag))
{
target += stretch;
} /* */
} /* if there's a symbol attached */
aim = target - address - fragP->fr_fix;
/* The displacement is affected by the instruction size
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* for the 32k architecture. I think we ought to be able
* to add fragP->fr_pcrel_adjust in all cases (it should be
* zero if not used), but just in case it breaks something
* else we'll put this inside #ifdef NS32K ... #endif
*/
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#ifdef TC_NS32K
aim += fragP->fr_pcrel_adjust;
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#endif /* TC_NS32K */
if (aim < 0)
{
/* Look backwards. */
for (next_state = this_type->rlx_more; next_state;)
{
if (aim >= this_type->rlx_backward)
{
next_state = 0;
}
else
{ /* Grow to next state. */
this_type = md_relax_table + (this_state = next_state);
next_state = this_type->rlx_more;
}
}
}
else
{
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#ifdef DONTDEF
/* JF these next few lines of code are for the mc68020 which can't handle short
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offsets of zero in branch instructions. What a kludge! */
if (aim == 0 && this_state == (1 << 2 + 0))
{ /* FOO hard encoded from m.c */
aim = this_type->rlx_forward + 1; /* Force relaxation into word mode */
}
#endif
#ifdef M68K_AIM_KLUDGE
M68K_AIM_KLUDGE (aim, this_state, this_type);
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#endif
/* JF end of 68020 code */
/* Look forwards. */
for (next_state = this_type->rlx_more; next_state;)
{
if (aim <= this_type->rlx_forward)
{
next_state = 0;
}
else
{ /* Grow to next state. */
this_type = md_relax_table + (this_state = next_state);
next_state = this_type->rlx_more;
}
}
}
if ((growth = this_type->rlx_length - start_type->rlx_length) != 0)
fragP->fr_subtype = this_state;
break;
} /* case rs_machine_dependent */
default:
BAD_CASE (fragP->fr_type);
break;
}
if (growth)
{
stretch += growth;
stretched++;
}
} /* For each frag in the segment. */
}
while (stretched); /* Until nothing further to relax. */
} /* do_relax */
/*
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* We now have valid fr_address'es for each frag.
*/
/*
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* All fr_address's are correct, relative to their own segment.
* We have made all the fixS we will ever make.
*/
} /* relax_segment() */
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/*
* Relax_align. Advance location counter to next address that has 'alignment'
* lowest order bits all 0s.
*/
/* How many addresses does the .align take? */
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static relax_addressT
relax_align (address, alignment)
register relax_addressT address; /* Address now. */
register long alignment; /* Alignment (binary). */
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{
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relax_addressT mask;
relax_addressT new_address;
mask = ~((~0) << alignment);
new_address = (address + mask) & (~mask);
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if (linkrelax)
/* We must provide lots of padding, so the linker can discard it
when needed. The linker will not add extra space, ever. */
new_address += (1 << alignment);
return (new_address - address);
} /* relax_align() */
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/* fixup_segment()
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Go through all the fixS's in a segment and see which ones can be
handled now. (These consist of fixS where we have since discovered
the value of a symbol, or the address of the frag involved.)
For each one, call md_apply_fix to put the fix into the frag data.
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Result is a count of how many relocation structs will be needed to
handle the remaining fixS's that we couldn't completely handle here.
These will be output later by emit_relocations(). */
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static long
fixup_segment (fixP, this_segment_type)
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register fixS *fixP;
segT this_segment_type; /* N_TYPE bits for segment. */
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{
register long seg_reloc_count;
register symbolS *add_symbolP;
register symbolS *sub_symbolP;
register long add_number;
register int size;
register char *place;
register long where;
register char pcrel;
register fragS *fragP;
register segT add_symbol_segment = SEG_ABSOLUTE;
/* FIXME: remove this line *//* fixS *orig = fixP; */
seg_reloc_count = 0;
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#ifdef TC_I960
/* If the linker is doing the relaxing, we must not do any fixups */
if (linkrelax)
{
for (; fixP; fixP = fixP->fx_next)
{
seg_reloc_count++;
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}
}
else
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#endif
for (; fixP; fixP = fixP->fx_next)
{
fragP = fixP->fx_frag;
know (fragP);
where = fixP->fx_where;
place = fragP->fr_literal + where;
size = fixP->fx_size;
add_symbolP = fixP->fx_addsy;
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#ifdef TC_I960
if (fixP->fx_callj && TC_S_IS_CALLNAME (add_symbolP))
{
/* Relocation should be done via the
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associated 'bal' entry point
symbol. */
if (!TC_S_IS_BALNAME (tc_get_bal_of_call (add_symbolP)))
{
as_bad ("No 'bal' entry point for leafproc %s",
S_GET_NAME (add_symbolP));
continue;
}
fixP->fx_addsy = add_symbolP = tc_get_bal_of_call (add_symbolP);
} /* callj relocation */
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#endif
sub_symbolP = fixP->fx_subsy;
add_number = fixP->fx_offset;
pcrel = fixP->fx_pcrel;
if (add_symbolP)
{
add_symbol_segment = S_GET_SEGMENT (add_symbolP);
} /* if there is an addend */
if (sub_symbolP)
{
if (!add_symbolP)
{
/* Its just -sym */
if (S_GET_SEGMENT (sub_symbolP) != SEG_ABSOLUTE)
{
as_bad ("Negative of non-absolute symbol %s", S_GET_NAME (sub_symbolP));
} /* not absolute */
add_number -= S_GET_VALUE (sub_symbolP);
/* if sub_symbol is in the same segment that add_symbol
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and add_symbol is either in DATA, TEXT, BSS or ABSOLUTE */
}
else if ((S_GET_SEGMENT (sub_symbolP) == add_symbol_segment)
&& (SEG_NORMAL (add_symbol_segment)
|| (add_symbol_segment == SEG_ABSOLUTE)))
{
/* Difference of 2 symbols from same segment. */
/* Can't make difference of 2 undefineds: 'value' means */
/* something different for N_UNDF. */
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#ifdef TC_I960
/* Makes no sense to use the difference of 2 arbitrary symbols
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* as the target of a call instruction.
*/
if (fixP->fx_callj)
{
as_bad ("callj to difference of 2 symbols");
}
#endif /* TC_I960 */
add_number += S_GET_VALUE (add_symbolP) -
S_GET_VALUE (sub_symbolP);
add_symbolP = NULL;
fixP->fx_addsy = NULL;
}
else
{
/* Different segments in subtraction. */
know (!(S_IS_EXTERNAL (sub_symbolP) && (S_GET_SEGMENT (sub_symbolP) == SEG_ABSOLUTE)));
if ((S_GET_SEGMENT (sub_symbolP) == SEG_ABSOLUTE))
{
add_number -= S_GET_VALUE (sub_symbolP);
}
else
{
as_bad ("Can't emit reloc {- %s-seg symbol \"%s\"} @ file address %d.",
segment_name (S_GET_SEGMENT (sub_symbolP)),
S_GET_NAME (sub_symbolP), fragP->fr_address + where);
} /* if absolute */
}
} /* if sub_symbolP */
if (add_symbolP)
{
if (add_symbol_segment == this_segment_type && pcrel)
{
/*
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* This fixup was made when the symbol's segment was
* SEG_UNKNOWN, but it is now in the local segment.
* So we know how to do the address without relocation.
*/
#ifdef TC_I960
/* reloc_callj() may replace a 'call' with a 'calls' or a 'bal',
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* in which cases it modifies *fixP as appropriate. In the case
* of a 'calls', no further work is required, and *fixP has been
* set up to make the rest of the code below a no-op.
*/
reloc_callj (fixP);
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#endif /* TC_I960 */
add_number += S_GET_VALUE (add_symbolP);
add_number -= md_pcrel_from (fixP);
pcrel = 0; /* Lie. Don't want further pcrel processing. */
fixP->fx_addsy = NULL; /* No relocations please. */
}
else
{
switch (add_symbol_segment)
{
case SEG_ABSOLUTE:
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#ifdef TC_I960
reloc_callj (fixP); /* See comment about reloc_callj() above*/
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#endif /* TC_I960 */
add_number += S_GET_VALUE (add_symbolP);
fixP->fx_addsy = NULL;
add_symbolP = NULL;
break;
default:
seg_reloc_count++;
add_number += S_GET_VALUE (add_symbolP);
break;
case SEG_UNKNOWN:
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#ifdef TC_I960
if ((int) fixP->fx_bit_fixP == 13)
{
/* This is a COBR instruction. They have only a
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* 13-bit displacement and are only to be used
* for local branches: flag as error, don't generate
* relocation.
*/
as_bad ("can't use COBR format with external label");
fixP->fx_addsy = NULL; /* No relocations please. */
continue;
} /* COBR */
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#endif /* TC_I960 */
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#ifdef OBJ_COFF
#ifdef TE_I386AIX
if (S_IS_COMMON (add_symbolP))
add_number += S_GET_VALUE (add_symbolP);
#endif /* TE_I386AIX */
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#endif /* OBJ_COFF */
++seg_reloc_count;
break;
} /* switch on symbol seg */
} /* if not in local seg */
} /* if there was a + symbol */
if (pcrel)
{
add_number -= md_pcrel_from (fixP);
if (add_symbolP == 0)
{
fixP->fx_addsy = &abs_symbol;
++seg_reloc_count;
} /* if there's an add_symbol */
} /* if pcrel */
if (!fixP->fx_bit_fixP)
{
if ((size == 1 &&
(add_number & ~0xFF) && ((add_number & ~0xFF) != (-1 & ~0xFF))) ||
(size == 2 &&
(add_number & ~0xFFFF) && ((add_number & ~0xFFFF) != (-1 & ~0xFFFF))))
{
as_bad ("Value of %d too large for field of %d bytes at 0x%x",
add_number, size, fragP->fr_address + where);
} /* generic error checking */
#ifdef WARN_SIGNED_OVERFLOW_WORD
/* Warn if a .word value is too large when
treated as a signed number. We already
know it is not too negative. This is to
catch over-large switches generated by gcc
on the 68k. */
if (!flagseen['J']
&& size == 2
&& add_number > 0x7fff)
as_bad ("Signed .word overflow; switch may be too large; %d at 0x%x",
add_number, fragP->fr_address + where);
#endif
} /* not a bit fix */
md_apply_fix (fixP, add_number);
} /* For each fixS in this segment. */
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#ifdef OBJ_COFF
#ifdef TC_I960
{
fixS *topP = fixP;
/* two relocs per callj under coff. */
for (fixP = topP; fixP; fixP = fixP->fx_next)
{
if (fixP->fx_callj && fixP->fx_addsy != 0)
{
++seg_reloc_count;
} /* if callj and not already fixed. */
} /* for each fix */
}
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#endif /* TC_I960 */
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#endif /* OBJ_COFF */
return (seg_reloc_count);
} /* fixup_segment() */
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static int
is_dnrange (f1, f2)
struct frag *f1;
struct frag *f2;
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{
while (f1)
{
if (f1->fr_next == f2)
return 1;
f1 = f1->fr_next;
}
return 0;
} /* is_dnrange() */
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/* Append a string onto another string, bumping the pointer along. */
void
append (charPP, fromP, length)
char **charPP;
char *fromP;
unsigned long length;
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{
if (length)
{ /* Don't trust memcpy() of 0 chars. */
memcpy (*charPP, fromP, (int) length);
*charPP += length;
}
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}
int section_alignment[SEG_MAXIMUM_ORDINAL];
/*
* This routine records the largest alignment seen for each segment.
* If the beginning of the segment is aligned on the worst-case
* boundary, all of the other alignments within it will work. At
* least one object format really uses this info.
*/
void
record_alignment (seg, align)
segT seg; /* Segment to which alignment pertains */
int align; /* Alignment, as a power of 2
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* (e.g., 1 => 2-byte boundary, 2 => 4-byte boundary, etc.)
*/
{
if (align > section_alignment[(int) seg])
{
section_alignment[(int) seg] = align;
} /* if highest yet */
return;
} /* record_alignment() */
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/*
* Local Variables:
* comment-column: 0
* fill-column: 131
* End:
*/
/* end of write.c */