1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
|
/* $OpenBSD: frags.c,v 1.2 1998/02/15 18:48:48 niklas Exp $ */
/* frags.c - manage frags -
Copyright (C) 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. */
#ifndef lint
static char rcsid[] = "$OpenBSD: frags.c,v 1.2 1998/02/15 18:48:48 niklas Exp $";
#endif
#include "as.h"
#include "subsegs.h"
#include "obstack.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)
unsigned 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_grow() */
/*
* 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 */
memset(frag_now, '\0', 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;
#ifndef NO_LISTING
{
extern struct list_info_struct *listing_tail;
frag_now->line = listing_tail;
}
#endif
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 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 offset;
char *opcode;
int 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;
} /* frag_align() */
/* end of frags.c */
|
