293 lines
7.9 KiB
C
293 lines
7.9 KiB
C
|
/* frags.c - manage frags -
|
|||
|
|
Copyright (C) 1987 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 1, 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. */
|
|||
|
|
|
|||
|
|
#include "as.h"
|
|||
|
|
#include "subsegs.h"
|
|||
|
|
#include "obstack.h"
|
|||
|
|
#include "frags.h"
|
|||
|
|
#include "struc-symbol.h"
|
|||
|
|
|
|||
|
|
struct obstack frags; /* All, and only, frags live here. */
|
|||
|
|
|
|||
|
|
fragS zero_address_frag = {
|
|||
|
|
0, /* fr_address */
|
|||
|
|
NULL, /* fr_next */
|
|||
|
|
0, /* fr_fix */
|
|||
|
|
0, /* fr_var */
|
|||
|
|
0, /* fr_symbol */
|
|||
|
|
0, /* fr_offset */
|
|||
|
|
NULL, /* fr_opcode */
|
|||
|
|
rs_fill, /* fr_type */
|
|||
|
|
0, /* fr_subtype */
|
|||
|
|
0, /* fr_pcrel_adjust */
|
|||
|
|
0, /* fr_bsr */
|
|||
|
|
0 /* fr_literal [0] */
|
|||
|
|
};
|
|||
|
|
|
|||
|
|
fragS bss_address_frag = {
|
|||
|
|
0, /* fr_address. Gets filled in to make up
|
|||
|
|
sy_value-s. */
|
|||
|
|
NULL, /* fr_next */
|
|||
|
|
0, /* fr_fix */
|
|||
|
|
0, /* fr_var */
|
|||
|
|
0, /* fr_symbol */
|
|||
|
|
0, /* fr_offset */
|
|||
|
|
NULL, /* fr_opcode */
|
|||
|
|
rs_fill, /* fr_type */
|
|||
|
|
0, /* fr_subtype */
|
|||
|
|
0, /* fr_pcrel_adjust */
|
|||
|
|
0, /* fr_bsr */
|
|||
|
|
0 /* fr_literal [0] */
|
|||
|
|
};
|
|||
|
|
|
|||
|
|
/*
|
|||
|
|
* frag_grow()
|
|||
|
|
*
|
|||
|
|
* Internal.
|
|||
|
|
* Try to augment current frag by nchars chars.
|
|||
|
|
* If there is no room, close of the current frag with a ".fill 0"
|
|||
|
|
* and begin a new frag. Unless the new frag has nchars chars available
|
|||
|
|
* do not return. Do not set up any fields of *now_frag.
|
|||
|
|
*/
|
|||
|
|
static void
|
|||
|
|
frag_grow (nchars)
|
|||
|
|
int nchars;
|
|||
|
|
{
|
|||
|
|
if (obstack_room (&frags) < nchars) {
|
|||
|
|
unsigned int n,oldn;
|
|||
|
|
long oldc;
|
|||
|
|
|
|||
|
|
frag_wane (frag_now);
|
|||
|
|
frag_new (0);
|
|||
|
|
oldn=(unsigned)-1;
|
|||
|
|
oldc=frags.chunk_size;
|
|||
|
|
frags.chunk_size=2*nchars;
|
|||
|
|
while((n=obstack_room(&frags))<nchars && n<oldn) {
|
|||
|
|
frag_wane(frag_now);
|
|||
|
|
frag_new(0);
|
|||
|
|
oldn=n;
|
|||
|
|
}
|
|||
|
|
frags.chunk_size=oldc;
|
|||
|
|
}
|
|||
|
|
if (obstack_room (&frags) < nchars)
|
|||
|
|
as_fatal ("Can't extend frag %d. chars", nchars);
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/*
|
|||
|
|
* frag_new()
|
|||
|
|
*
|
|||
|
|
* Call this to close off a completed frag, and start up a new (empty)
|
|||
|
|
* frag, in the same subsegment as the old frag.
|
|||
|
|
* [frchain_now remains the same but frag_now is updated.]
|
|||
|
|
* Because this calculates the correct value of fr_fix by
|
|||
|
|
* looking at the obstack 'frags', it needs to know how many
|
|||
|
|
* characters at the end of the old frag belong to (the maximal)
|
|||
|
|
* fr_var: the rest must belong to fr_fix.
|
|||
|
|
* It doesn't actually set up the old frag's fr_var: you may have
|
|||
|
|
* set fr_var == 1, but allocated 10 chars to the end of the frag:
|
|||
|
|
* in this case you pass old_frags_var_max_size == 10.
|
|||
|
|
*
|
|||
|
|
* Make a new frag, initialising some components. Link new frag at end
|
|||
|
|
* of frchain_now.
|
|||
|
|
*/
|
|||
|
|
void
|
|||
|
|
frag_new (old_frags_var_max_size)
|
|||
|
|
int old_frags_var_max_size; /* Number of chars (already allocated on
|
|||
|
|
obstack frags) */
|
|||
|
|
/* in variable_length part of frag. */
|
|||
|
|
{
|
|||
|
|
register fragS * former_last_fragP;
|
|||
|
|
/* char *throw_away_pointer; JF unused */
|
|||
|
|
register frchainS * frchP;
|
|||
|
|
long tmp; /* JF */
|
|||
|
|
|
|||
|
|
frag_now->fr_fix = (char *) (obstack_next_free (&frags)) -
|
|||
|
|
(frag_now->fr_literal) - old_frags_var_max_size;
|
|||
|
|
/* Fix up old frag's fr_fix. */
|
|||
|
|
|
|||
|
|
obstack_finish (&frags);
|
|||
|
|
/* This will align the obstack so the */
|
|||
|
|
/* next struct we allocate on it will */
|
|||
|
|
/* begin at a correct boundary. */
|
|||
|
|
frchP = frchain_now;
|
|||
|
|
know (frchP);
|
|||
|
|
former_last_fragP = frchP->frch_last;
|
|||
|
|
know (former_last_fragP);
|
|||
|
|
know (former_last_fragP == frag_now);
|
|||
|
|
obstack_blank (&frags, SIZEOF_STRUCT_FRAG);
|
|||
|
|
/* We expect this will begin at a correct */
|
|||
|
|
/* boundary for a struct. */
|
|||
|
|
tmp=obstack_alignment_mask(&frags);
|
|||
|
|
obstack_alignment_mask(&frags)=0; /* Turn off alignment */
|
|||
|
|
/* If we ever hit a machine
|
|||
|
|
where strings must be
|
|||
|
|
aligned, we Lose Big */
|
|||
|
|
frag_now=(fragS *)obstack_finish(&frags);
|
|||
|
|
obstack_alignment_mask(&frags)=tmp; /* Restore alignment */
|
|||
|
|
|
|||
|
|
/* Just in case we don't get zero'd bytes */
|
|||
|
|
bzero(frag_now, SIZEOF_STRUCT_FRAG);
|
|||
|
|
|
|||
|
|
/* obstack_unaligned_done (&frags, &frag_now); */
|
|||
|
|
/* know (frags.obstack_c_next_free == frag_now->fr_literal); */
|
|||
|
|
/* Generally, frag_now->points to an */
|
|||
|
|
/* address rounded up to next alignment. */
|
|||
|
|
/* However, characters will add to obstack */
|
|||
|
|
/* frags IMMEDIATELY after the struct frag, */
|
|||
|
|
/* even if they are not starting at an */
|
|||
|
|
/* alignment address. */
|
|||
|
|
former_last_fragP->fr_next = frag_now;
|
|||
|
|
frchP->frch_last = frag_now;
|
|||
|
|
frag_now->fr_next = NULL;
|
|||
|
|
} /* frag_new() */
|
|||
|
|
|
|||
|
|
/*
|
|||
|
|
* frag_more()
|
|||
|
|
*
|
|||
|
|
* Start a new frag unless we have n more chars of room in the current frag.
|
|||
|
|
* Close off the old frag with a .fill 0.
|
|||
|
|
*
|
|||
|
|
* Return the address of the 1st char to write into. Advance
|
|||
|
|
* frag_now_growth past the new chars.
|
|||
|
|
*/
|
|||
|
|
|
|||
|
|
char *
|
|||
|
|
frag_more (nchars)
|
|||
|
|
int nchars;
|
|||
|
|
{
|
|||
|
|
register char *retval;
|
|||
|
|
|
|||
|
|
frag_grow (nchars);
|
|||
|
|
retval = obstack_next_free (&frags);
|
|||
|
|
obstack_blank_fast (&frags, nchars);
|
|||
|
|
return (retval);
|
|||
|
|
} /* frag_more() */
|
|||
|
|
|
|||
|
|
/*
|
|||
|
|
* frag_var()
|
|||
|
|
*
|
|||
|
|
* Start a new frag unless we have max_chars more chars of room in the current frag.
|
|||
|
|
* Close off the old frag with a .fill 0.
|
|||
|
|
*
|
|||
|
|
* Set up a machine_dependent relaxable frag, then start a new frag.
|
|||
|
|
* Return the address of the 1st char of the var part of the old frag
|
|||
|
|
* to write into.
|
|||
|
|
*/
|
|||
|
|
|
|||
|
|
char *
|
|||
|
|
frag_var (type, max_chars, var, subtype, symbol, offset, opcode)
|
|||
|
|
relax_stateT type;
|
|||
|
|
int max_chars;
|
|||
|
|
int var;
|
|||
|
|
relax_substateT subtype;
|
|||
|
|
symbolS * symbol;
|
|||
|
|
long int offset;
|
|||
|
|
char * opcode;
|
|||
|
|
{
|
|||
|
|
register char *retval;
|
|||
|
|
|
|||
|
|
frag_grow (max_chars);
|
|||
|
|
retval = obstack_next_free (&frags);
|
|||
|
|
obstack_blank_fast (&frags, max_chars);
|
|||
|
|
frag_now->fr_var = var;
|
|||
|
|
frag_now->fr_type = type;
|
|||
|
|
frag_now->fr_subtype = subtype;
|
|||
|
|
frag_now->fr_symbol = symbol;
|
|||
|
|
frag_now->fr_offset = offset;
|
|||
|
|
frag_now->fr_opcode = opcode;
|
|||
|
|
/* default these to zero. */
|
|||
|
|
frag_now->fr_pcrel_adjust = 0;
|
|||
|
|
frag_now->fr_bsr = 0;
|
|||
|
|
frag_new (max_chars);
|
|||
|
|
return (retval);
|
|||
|
|
} /* frag_var() */
|
|||
|
|
|
|||
|
|
/*
|
|||
|
|
* frag_variant()
|
|||
|
|
*
|
|||
|
|
* OVE: This variant of frag_var assumes that space for the tail has been
|
|||
|
|
* allocated by caller.
|
|||
|
|
* No call to frag_grow is done.
|
|||
|
|
* Two new arguments have been added.
|
|||
|
|
*/
|
|||
|
|
|
|||
|
|
char *
|
|||
|
|
frag_variant (type, max_chars, var, subtype, symbol, offset, opcode, pcrel_adjust,bsr)
|
|||
|
|
relax_stateT type;
|
|||
|
|
int max_chars;
|
|||
|
|
int var;
|
|||
|
|
relax_substateT subtype;
|
|||
|
|
symbolS *symbol;
|
|||
|
|
long int offset;
|
|||
|
|
char *opcode;
|
|||
|
|
char pcrel_adjust;
|
|||
|
|
char bsr;
|
|||
|
|
{
|
|||
|
|
register char *retval;
|
|||
|
|
|
|||
|
|
/* frag_grow (max_chars); */
|
|||
|
|
retval = obstack_next_free (&frags);
|
|||
|
|
/* obstack_blank_fast (&frags, max_chars); */ /* OVE: so far the only diff */
|
|||
|
|
frag_now->fr_var = var;
|
|||
|
|
frag_now->fr_type = type;
|
|||
|
|
frag_now->fr_subtype = subtype;
|
|||
|
|
frag_now->fr_symbol = symbol;
|
|||
|
|
frag_now->fr_offset = offset;
|
|||
|
|
frag_now->fr_opcode = opcode;
|
|||
|
|
frag_now->fr_pcrel_adjust = pcrel_adjust;
|
|||
|
|
frag_now->fr_bsr = bsr;
|
|||
|
|
frag_new (max_chars);
|
|||
|
|
return (retval);
|
|||
|
|
} /* frag_variant() */
|
|||
|
|
|
|||
|
|
/*
|
|||
|
|
* frag_wane()
|
|||
|
|
*
|
|||
|
|
* Reduce the variable end of a frag to a harmless state.
|
|||
|
|
*/
|
|||
|
|
void
|
|||
|
|
frag_wane (fragP)
|
|||
|
|
register fragS * fragP;
|
|||
|
|
{
|
|||
|
|
fragP->fr_type = rs_fill;
|
|||
|
|
fragP->fr_offset = 0;
|
|||
|
|
fragP->fr_var = 0;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/*
|
|||
|
|
* frag_align()
|
|||
|
|
*
|
|||
|
|
* Make a frag for ".align foo,bar". Call is "frag_align (foo,bar);".
|
|||
|
|
* Foo & bar are absolute integers.
|
|||
|
|
*
|
|||
|
|
* Call to close off the current frag with a ".align", then start a new
|
|||
|
|
* (so far empty) frag, in the same subsegment as the last frag.
|
|||
|
|
*/
|
|||
|
|
|
|||
|
|
void
|
|||
|
|
frag_align (alignment, fill_character)
|
|||
|
|
int alignment;
|
|||
|
|
int fill_character;
|
|||
|
|
{
|
|||
|
|
*(frag_var (rs_align, 1, 1, (relax_substateT)0, (symbolS *)0,
|
|||
|
|
(long)alignment, (char *)0)) = fill_character;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
/* end: frags.c */
|