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7306ed3f | 1 | /* C-compiler utilities for types and variables storage layout |
06ceef4e | 2 | Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1996, 1998, |
b8089d8d | 3 | 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc. |
7306ed3f | 4 | |
1322177d | 5 | This file is part of GCC. |
7306ed3f | 6 | |
1322177d LB |
7 | GCC is free software; you can redistribute it and/or modify it under |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
7306ed3f | 11 | |
1322177d LB |
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
7306ed3f JW |
16 | |
17 | You should have received a copy of the GNU General Public License | |
1322177d LB |
18 | along with GCC; see the file COPYING. If not, write to the Free |
19 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA | |
20 | 02111-1307, USA. */ | |
7306ed3f JW |
21 | |
22 | ||
23 | #include "config.h" | |
670ee920 | 24 | #include "system.h" |
4977bab6 ZW |
25 | #include "coretypes.h" |
26 | #include "tm.h" | |
7306ed3f | 27 | #include "tree.h" |
d05a5492 | 28 | #include "rtl.h" |
6baf1cc8 | 29 | #include "tm_p.h" |
566cdc73 | 30 | #include "flags.h" |
7306ed3f | 31 | #include "function.h" |
234042f4 | 32 | #include "expr.h" |
10f0ad3d | 33 | #include "toplev.h" |
d7db6646 | 34 | #include "ggc.h" |
f913c102 | 35 | #include "target.h" |
43577e6b | 36 | #include "langhooks.h" |
7306ed3f | 37 | |
fed3cef0 RK |
38 | /* Set to one when set_sizetype has been called. */ |
39 | static int sizetype_set; | |
40 | ||
41 | /* List of types created before set_sizetype has been called. We do not | |
42 | make this a GGC root since we want these nodes to be reclaimed. */ | |
43 | static tree early_type_list; | |
44 | ||
7306ed3f | 45 | /* Data type for the expressions representing sizes of data types. |
896cced4 | 46 | It is the first integer type laid out. */ |
fed3cef0 | 47 | tree sizetype_tab[(int) TYPE_KIND_LAST]; |
7306ed3f | 48 | |
d4c40650 RS |
49 | /* If nonzero, this is an upper limit on alignment of structure fields. |
50 | The value is measured in bits. */ | |
729a2125 | 51 | unsigned int maximum_field_alignment; |
d4c40650 | 52 | |
0e9e1e0a | 53 | /* If nonzero, the alignment of a bitstring or (power-)set value, in bits. |
b5d11e41 | 54 | May be overridden by front-ends. */ |
729a2125 | 55 | unsigned int set_alignment = 0; |
b5d11e41 | 56 | |
b5d6a2ff RK |
57 | /* Nonzero if all REFERENCE_TYPEs are internal and hence should be |
58 | allocated in Pmode, not ptr_mode. Set only by internal_reference_types | |
59 | called only by a front end. */ | |
60 | static int reference_types_internal = 0; | |
61 | ||
770ae6cc | 62 | static void finalize_record_size PARAMS ((record_layout_info)); |
770ae6cc RK |
63 | static void finalize_type_size PARAMS ((tree)); |
64 | static void place_union_field PARAMS ((record_layout_info, tree)); | |
b8089d8d | 65 | #if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED) |
4977bab6 ZW |
66 | static int excess_unit_span PARAMS ((HOST_WIDE_INT, HOST_WIDE_INT, |
67 | HOST_WIDE_INT, HOST_WIDE_INT, | |
68 | tree)); | |
b8089d8d | 69 | #endif |
0645ba8f MM |
70 | static unsigned int update_alignment_for_field |
71 | PARAMS ((record_layout_info, tree, | |
72 | unsigned int)); | |
36244024 | 73 | extern void debug_rli PARAMS ((record_layout_info)); |
7306ed3f JW |
74 | \f |
75 | /* SAVE_EXPRs for sizes of types and decls, waiting to be expanded. */ | |
76 | ||
e2500fed | 77 | static GTY(()) tree pending_sizes; |
7306ed3f JW |
78 | |
79 | /* Nonzero means cannot safely call expand_expr now, | |
80 | so put variable sizes onto `pending_sizes' instead. */ | |
81 | ||
82 | int immediate_size_expand; | |
83 | ||
b5d6a2ff RK |
84 | /* Show that REFERENCE_TYPES are internal and should be Pmode. Called only |
85 | by front end. */ | |
86 | ||
87 | void | |
88 | internal_reference_types () | |
89 | { | |
90 | reference_types_internal = 1; | |
91 | } | |
92 | ||
770ae6cc RK |
93 | /* Get a list of all the objects put on the pending sizes list. */ |
94 | ||
7306ed3f JW |
95 | tree |
96 | get_pending_sizes () | |
97 | { | |
98 | tree chain = pending_sizes; | |
4e4b555d RS |
99 | tree t; |
100 | ||
101 | /* Put each SAVE_EXPR into the current function. */ | |
102 | for (t = chain; t; t = TREE_CHAIN (t)) | |
103 | SAVE_EXPR_CONTEXT (TREE_VALUE (t)) = current_function_decl; | |
d4b60170 | 104 | |
7306ed3f JW |
105 | pending_sizes = 0; |
106 | return chain; | |
107 | } | |
108 | ||
0e9e1e0a | 109 | /* Return nonzero if EXPR is present on the pending sizes list. */ |
fe375cf1 JJ |
110 | |
111 | int | |
112 | is_pending_size (expr) | |
113 | tree expr; | |
114 | { | |
115 | tree t; | |
116 | ||
117 | for (t = pending_sizes; t; t = TREE_CHAIN (t)) | |
118 | if (TREE_VALUE (t) == expr) | |
119 | return 1; | |
120 | return 0; | |
121 | } | |
122 | ||
123 | /* Add EXPR to the pending sizes list. */ | |
124 | ||
125 | void | |
126 | put_pending_size (expr) | |
127 | tree expr; | |
128 | { | |
3874585e RK |
129 | /* Strip any simple arithmetic from EXPR to see if it has an underlying |
130 | SAVE_EXPR. */ | |
a9ecacf6 | 131 | expr = skip_simple_arithmetic (expr); |
3874585e RK |
132 | |
133 | if (TREE_CODE (expr) == SAVE_EXPR) | |
134 | pending_sizes = tree_cons (NULL_TREE, expr, pending_sizes); | |
fe375cf1 JJ |
135 | } |
136 | ||
770ae6cc RK |
137 | /* Put a chain of objects into the pending sizes list, which must be |
138 | empty. */ | |
139 | ||
1fd7c4ac RK |
140 | void |
141 | put_pending_sizes (chain) | |
142 | tree chain; | |
143 | { | |
144 | if (pending_sizes) | |
145 | abort (); | |
146 | ||
147 | pending_sizes = chain; | |
148 | } | |
149 | ||
76ffb3a0 | 150 | /* Given a size SIZE that may not be a constant, return a SAVE_EXPR |
7306ed3f JW |
151 | to serve as the actual size-expression for a type or decl. */ |
152 | ||
4e4b555d | 153 | tree |
7306ed3f JW |
154 | variable_size (size) |
155 | tree size; | |
156 | { | |
3695c25f JM |
157 | tree save; |
158 | ||
5e9bec99 RK |
159 | /* If the language-processor is to take responsibility for variable-sized |
160 | items (e.g., languages which have elaboration procedures like Ada), | |
ac79cd5a RK |
161 | just return SIZE unchanged. Likewise for self-referential sizes and |
162 | constant sizes. */ | |
76ffb3a0 | 163 | if (TREE_CONSTANT (size) |
43577e6b NB |
164 | || (*lang_hooks.decls.global_bindings_p) () < 0 |
165 | || contains_placeholder_p (size)) | |
5e9bec99 RK |
166 | return size; |
167 | ||
3695c25f JM |
168 | if (TREE_CODE (size) == MINUS_EXPR && integer_onep (TREE_OPERAND (size, 1))) |
169 | /* If this is the upper bound of a C array, leave the minus 1 outside | |
170 | the SAVE_EXPR so it can be folded away. */ | |
171 | TREE_OPERAND (size, 0) = save = save_expr (TREE_OPERAND (size, 0)); | |
172 | else | |
173 | size = save = save_expr (size); | |
68de3831 | 174 | |
d26f8097 MM |
175 | /* If an array with a variable number of elements is declared, and |
176 | the elements require destruction, we will emit a cleanup for the | |
177 | array. That cleanup is run both on normal exit from the block | |
178 | and in the exception-handler for the block. Normally, when code | |
179 | is used in both ordinary code and in an exception handler it is | |
180 | `unsaved', i.e., all SAVE_EXPRs are recalculated. However, we do | |
181 | not wish to do that here; the array-size is the same in both | |
182 | places. */ | |
3695c25f JM |
183 | if (TREE_CODE (save) == SAVE_EXPR) |
184 | SAVE_EXPR_PERSISTENT_P (save) = 1; | |
d26f8097 | 185 | |
43577e6b | 186 | if ((*lang_hooks.decls.global_bindings_p) ()) |
7306ed3f | 187 | { |
80f9c711 RS |
188 | if (TREE_CONSTANT (size)) |
189 | error ("type size can't be explicitly evaluated"); | |
190 | else | |
191 | error ("variable-size type declared outside of any function"); | |
192 | ||
fed3cef0 | 193 | return size_one_node; |
7306ed3f JW |
194 | } |
195 | ||
196 | if (immediate_size_expand) | |
3695c25f | 197 | expand_expr (save, const0_rtx, VOIDmode, 0); |
770ae6cc | 198 | else if (cfun != 0 && cfun->x_dont_save_pending_sizes_p) |
d43163b7 MM |
199 | /* The front-end doesn't want us to keep a list of the expressions |
200 | that determine sizes for variable size objects. */ | |
201 | ; | |
fe375cf1 | 202 | else |
3695c25f | 203 | put_pending_size (save); |
7306ed3f JW |
204 | |
205 | return size; | |
206 | } | |
207 | \f | |
208 | #ifndef MAX_FIXED_MODE_SIZE | |
209 | #define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (DImode) | |
210 | #endif | |
211 | ||
212 | /* Return the machine mode to use for a nonscalar of SIZE bits. | |
213 | The mode must be in class CLASS, and have exactly that many bits. | |
214 | If LIMIT is nonzero, modes of wider than MAX_FIXED_MODE_SIZE will not | |
215 | be used. */ | |
216 | ||
217 | enum machine_mode | |
218 | mode_for_size (size, class, limit) | |
770ae6cc | 219 | unsigned int size; |
7306ed3f JW |
220 | enum mode_class class; |
221 | int limit; | |
222 | { | |
b3694847 | 223 | enum machine_mode mode; |
7306ed3f | 224 | |
72c602fc | 225 | if (limit && size > MAX_FIXED_MODE_SIZE) |
7306ed3f JW |
226 | return BLKmode; |
227 | ||
5e9bec99 | 228 | /* Get the first mode which has this size, in the specified class. */ |
7306ed3f JW |
229 | for (mode = GET_CLASS_NARROWEST_MODE (class); mode != VOIDmode; |
230 | mode = GET_MODE_WIDER_MODE (mode)) | |
72c602fc | 231 | if (GET_MODE_BITSIZE (mode) == size) |
7306ed3f JW |
232 | return mode; |
233 | ||
234 | return BLKmode; | |
235 | } | |
236 | ||
72c602fc RK |
237 | /* Similar, except passed a tree node. */ |
238 | ||
239 | enum machine_mode | |
240 | mode_for_size_tree (size, class, limit) | |
241 | tree size; | |
242 | enum mode_class class; | |
243 | int limit; | |
244 | { | |
245 | if (TREE_CODE (size) != INTEGER_CST | |
5826955d | 246 | || TREE_OVERFLOW (size) |
72c602fc RK |
247 | /* What we really want to say here is that the size can fit in a |
248 | host integer, but we know there's no way we'd find a mode for | |
249 | this many bits, so there's no point in doing the precise test. */ | |
05bccae2 | 250 | || compare_tree_int (size, 1000) > 0) |
72c602fc RK |
251 | return BLKmode; |
252 | else | |
0384674e | 253 | return mode_for_size (tree_low_cst (size, 1), class, limit); |
72c602fc RK |
254 | } |
255 | ||
5e9bec99 RK |
256 | /* Similar, but never return BLKmode; return the narrowest mode that |
257 | contains at least the requested number of bits. */ | |
258 | ||
27922c13 | 259 | enum machine_mode |
5e9bec99 | 260 | smallest_mode_for_size (size, class) |
770ae6cc | 261 | unsigned int size; |
5e9bec99 RK |
262 | enum mode_class class; |
263 | { | |
b3694847 | 264 | enum machine_mode mode; |
5e9bec99 RK |
265 | |
266 | /* Get the first mode which has at least this size, in the | |
267 | specified class. */ | |
268 | for (mode = GET_CLASS_NARROWEST_MODE (class); mode != VOIDmode; | |
269 | mode = GET_MODE_WIDER_MODE (mode)) | |
72c602fc | 270 | if (GET_MODE_BITSIZE (mode) >= size) |
5e9bec99 RK |
271 | return mode; |
272 | ||
273 | abort (); | |
274 | } | |
275 | ||
d006aa54 RH |
276 | /* Find an integer mode of the exact same size, or BLKmode on failure. */ |
277 | ||
278 | enum machine_mode | |
279 | int_mode_for_mode (mode) | |
280 | enum machine_mode mode; | |
281 | { | |
282 | switch (GET_MODE_CLASS (mode)) | |
283 | { | |
284 | case MODE_INT: | |
285 | case MODE_PARTIAL_INT: | |
286 | break; | |
287 | ||
288 | case MODE_COMPLEX_INT: | |
289 | case MODE_COMPLEX_FLOAT: | |
290 | case MODE_FLOAT: | |
62c07905 JM |
291 | case MODE_VECTOR_INT: |
292 | case MODE_VECTOR_FLOAT: | |
d006aa54 RH |
293 | mode = mode_for_size (GET_MODE_BITSIZE (mode), MODE_INT, 0); |
294 | break; | |
295 | ||
296 | case MODE_RANDOM: | |
297 | if (mode == BLKmode) | |
786de7eb | 298 | break; |
d4b60170 | 299 | |
2d76cb1a | 300 | /* ... fall through ... */ |
d006aa54 RH |
301 | |
302 | case MODE_CC: | |
303 | default: | |
05bccae2 | 304 | abort (); |
d006aa54 RH |
305 | } |
306 | ||
307 | return mode; | |
308 | } | |
309 | ||
187515f5 AO |
310 | /* Return the alignment of MODE. This will be bounded by 1 and |
311 | BIGGEST_ALIGNMENT. */ | |
312 | ||
313 | unsigned int | |
314 | get_mode_alignment (mode) | |
315 | enum machine_mode mode; | |
316 | { | |
317 | unsigned int alignment; | |
318 | ||
319 | if (GET_MODE_CLASS (mode) == MODE_COMPLEX_FLOAT | |
320 | || GET_MODE_CLASS (mode) == MODE_COMPLEX_INT) | |
321 | alignment = GET_MODE_UNIT_SIZE (mode); | |
322 | else | |
323 | alignment = GET_MODE_SIZE (mode); | |
324 | ||
325 | /* Extract the LSB of the size. */ | |
326 | alignment = alignment & -alignment; | |
327 | alignment *= BITS_PER_UNIT; | |
328 | ||
329 | alignment = MIN (BIGGEST_ALIGNMENT, MAX (1, alignment)); | |
330 | return alignment; | |
331 | } | |
332 | ||
fed3cef0 RK |
333 | /* Return the value of VALUE, rounded up to a multiple of DIVISOR. |
334 | This can only be applied to objects of a sizetype. */ | |
7306ed3f JW |
335 | |
336 | tree | |
337 | round_up (value, divisor) | |
338 | tree value; | |
339 | int divisor; | |
340 | { | |
fed3cef0 RK |
341 | tree arg = size_int_type (divisor, TREE_TYPE (value)); |
342 | ||
343 | return size_binop (MULT_EXPR, size_binop (CEIL_DIV_EXPR, value, arg), arg); | |
344 | } | |
345 | ||
346 | /* Likewise, but round down. */ | |
347 | ||
348 | tree | |
349 | round_down (value, divisor) | |
350 | tree value; | |
351 | int divisor; | |
352 | { | |
353 | tree arg = size_int_type (divisor, TREE_TYPE (value)); | |
354 | ||
355 | return size_binop (MULT_EXPR, size_binop (FLOOR_DIV_EXPR, value, arg), arg); | |
7306ed3f JW |
356 | } |
357 | \f | |
78d55cc8 JM |
358 | /* Subroutine of layout_decl: Force alignment required for the data type. |
359 | But if the decl itself wants greater alignment, don't override that. */ | |
360 | ||
361 | static inline void | |
362 | do_type_align (tree type, tree decl) | |
363 | { | |
364 | if (TYPE_ALIGN (type) > DECL_ALIGN (decl)) | |
365 | { | |
366 | DECL_ALIGN (decl) = TYPE_ALIGN (type); | |
367 | DECL_USER_ALIGN (decl) = TYPE_USER_ALIGN (type); | |
368 | } | |
369 | } | |
370 | ||
7306ed3f JW |
371 | /* Set the size, mode and alignment of a ..._DECL node. |
372 | TYPE_DECL does need this for C++. | |
373 | Note that LABEL_DECL and CONST_DECL nodes do not need this, | |
374 | and FUNCTION_DECL nodes have them set up in a special (and simple) way. | |
375 | Don't call layout_decl for them. | |
376 | ||
377 | KNOWN_ALIGN is the amount of alignment we can assume this | |
378 | decl has with no special effort. It is relevant only for FIELD_DECLs | |
379 | and depends on the previous fields. | |
380 | All that matters about KNOWN_ALIGN is which powers of 2 divide it. | |
381 | If KNOWN_ALIGN is 0, it means, "as much alignment as you like": | |
382 | the record will be aligned to suit. */ | |
383 | ||
384 | void | |
385 | layout_decl (decl, known_align) | |
386 | tree decl; | |
729a2125 | 387 | unsigned int known_align; |
7306ed3f | 388 | { |
b3694847 SS |
389 | tree type = TREE_TYPE (decl); |
390 | enum tree_code code = TREE_CODE (decl); | |
a46666a9 | 391 | rtx rtl = NULL_RTX; |
7306ed3f JW |
392 | |
393 | if (code == CONST_DECL) | |
394 | return; | |
9df2c88c | 395 | else if (code != VAR_DECL && code != PARM_DECL && code != RESULT_DECL |
33433751 | 396 | && code != TYPE_DECL && code != FIELD_DECL) |
7306ed3f JW |
397 | abort (); |
398 | ||
a46666a9 RH |
399 | rtl = DECL_RTL_IF_SET (decl); |
400 | ||
7306ed3f | 401 | if (type == error_mark_node) |
33433751 | 402 | type = void_type_node; |
7306ed3f | 403 | |
770ae6cc RK |
404 | /* Usually the size and mode come from the data type without change, |
405 | however, the front-end may set the explicit width of the field, so its | |
406 | size may not be the same as the size of its type. This happens with | |
407 | bitfields, of course (an `int' bitfield may be only 2 bits, say), but it | |
408 | also happens with other fields. For example, the C++ front-end creates | |
409 | zero-sized fields corresponding to empty base classes, and depends on | |
410 | layout_type setting DECL_FIELD_BITPOS correctly for the field. Set the | |
4b6bf620 RK |
411 | size in bytes from the size in bits. If we have already set the mode, |
412 | don't set it again since we can be called twice for FIELD_DECLs. */ | |
770ae6cc | 413 | |
7306ed3f | 414 | TREE_UNSIGNED (decl) = TREE_UNSIGNED (type); |
4b6bf620 RK |
415 | if (DECL_MODE (decl) == VOIDmode) |
416 | DECL_MODE (decl) = TYPE_MODE (type); | |
770ae6cc | 417 | |
5e9bec99 | 418 | if (DECL_SIZE (decl) == 0) |
06ceef4e RK |
419 | { |
420 | DECL_SIZE (decl) = TYPE_SIZE (type); | |
421 | DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (type); | |
422 | } | |
1a96dc46 | 423 | else if (DECL_SIZE_UNIT (decl) == 0) |
770ae6cc RK |
424 | DECL_SIZE_UNIT (decl) |
425 | = convert (sizetype, size_binop (CEIL_DIV_EXPR, DECL_SIZE (decl), | |
426 | bitsize_unit_node)); | |
06ceef4e | 427 | |
78d55cc8 JM |
428 | if (code != FIELD_DECL) |
429 | /* For non-fields, update the alignment from the type. */ | |
430 | do_type_align (type, decl); | |
431 | else | |
432 | /* For fields, it's a bit more complicated... */ | |
786de7eb | 433 | { |
78d55cc8 JM |
434 | if (DECL_BIT_FIELD (decl)) |
435 | { | |
436 | DECL_BIT_FIELD_TYPE (decl) = type; | |
7306ed3f | 437 | |
78d55cc8 JM |
438 | /* A zero-length bit-field affects the alignment of the next |
439 | field. */ | |
440 | if (integer_zerop (DECL_SIZE (decl)) | |
441 | && ! DECL_PACKED (decl) | |
442 | && ! (*targetm.ms_bitfield_layout_p) (DECL_FIELD_CONTEXT (decl))) | |
443 | { | |
444 | #ifdef PCC_BITFIELD_TYPE_MATTERS | |
445 | if (PCC_BITFIELD_TYPE_MATTERS) | |
446 | do_type_align (type, decl); | |
447 | else | |
448 | #endif | |
ad3f5759 | 449 | { |
78d55cc8 | 450 | #ifdef EMPTY_FIELD_BOUNDARY |
ad3f5759 AS |
451 | if (EMPTY_FIELD_BOUNDARY > DECL_ALIGN (decl)) |
452 | { | |
453 | DECL_ALIGN (decl) = EMPTY_FIELD_BOUNDARY; | |
454 | DECL_USER_ALIGN (decl) = 0; | |
455 | } | |
78d55cc8 | 456 | #endif |
ad3f5759 | 457 | } |
78d55cc8 JM |
458 | } |
459 | ||
460 | /* See if we can use an ordinary integer mode for a bit-field. | |
461 | Conditions are: a fixed size that is correct for another mode | |
462 | and occupying a complete byte or bytes on proper boundary. */ | |
463 | if (TYPE_SIZE (type) != 0 | |
464 | && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST | |
465 | && GET_MODE_CLASS (TYPE_MODE (type)) == MODE_INT) | |
466 | { | |
467 | enum machine_mode xmode | |
468 | = mode_for_size_tree (DECL_SIZE (decl), MODE_INT, 1); | |
469 | ||
470 | if (xmode != BLKmode && known_align >= GET_MODE_ALIGNMENT (xmode)) | |
471 | { | |
472 | DECL_ALIGN (decl) = MAX (GET_MODE_ALIGNMENT (xmode), | |
473 | DECL_ALIGN (decl)); | |
474 | DECL_MODE (decl) = xmode; | |
475 | DECL_BIT_FIELD (decl) = 0; | |
476 | } | |
477 | } | |
478 | ||
479 | /* Turn off DECL_BIT_FIELD if we won't need it set. */ | |
480 | if (TYPE_MODE (type) == BLKmode && DECL_MODE (decl) == BLKmode | |
481 | && known_align >= TYPE_ALIGN (type) | |
482 | && DECL_ALIGN (decl) >= TYPE_ALIGN (type)) | |
483 | DECL_BIT_FIELD (decl) = 0; | |
484 | } | |
485 | else if (DECL_PACKED (decl) && DECL_USER_ALIGN (decl)) | |
486 | /* Don't touch DECL_ALIGN. For other packed fields, go ahead and | |
487 | round up; we'll reduce it again below. */; | |
488 | else | |
489 | do_type_align (type, decl); | |
6790d1bd RK |
490 | |
491 | /* If the field is of variable size, we can't misalign it since we | |
492 | have no way to make a temporary to align the result. But this | |
493 | isn't an issue if the decl is not addressable. Likewise if it | |
494 | is of unknown size. */ | |
78d55cc8 JM |
495 | if (DECL_PACKED (decl) |
496 | && !DECL_USER_ALIGN (decl) | |
497 | && (DECL_NONADDRESSABLE_P (decl) | |
498 | || DECL_SIZE_UNIT (decl) == 0 | |
499 | || TREE_CODE (DECL_SIZE_UNIT (decl)) == INTEGER_CST)) | |
500 | DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), BITS_PER_UNIT); | |
501 | ||
502 | /* Should this be controlled by DECL_USER_ALIGN, too? */ | |
503 | if (maximum_field_alignment != 0) | |
504 | DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), maximum_field_alignment); | |
505 | if (! DECL_USER_ALIGN (decl)) | |
7306ed3f | 506 | { |
78d55cc8 JM |
507 | /* Some targets (i.e. i386, VMS) limit struct field alignment |
508 | to a lower boundary than alignment of variables unless | |
509 | it was overridden by attribute aligned. */ | |
510 | #ifdef BIGGEST_FIELD_ALIGNMENT | |
511 | DECL_ALIGN (decl) | |
512 | = MIN (DECL_ALIGN (decl), (unsigned) BIGGEST_FIELD_ALIGNMENT); | |
513 | #endif | |
514 | #ifdef ADJUST_FIELD_ALIGN | |
515 | DECL_ALIGN (decl) = ADJUST_FIELD_ALIGN (decl, DECL_ALIGN (decl)); | |
516 | #endif | |
7306ed3f JW |
517 | } |
518 | } | |
519 | ||
520 | /* Evaluate nonconstant size only once, either now or as soon as safe. */ | |
521 | if (DECL_SIZE (decl) != 0 && TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST) | |
522 | DECL_SIZE (decl) = variable_size (DECL_SIZE (decl)); | |
06ceef4e RK |
523 | if (DECL_SIZE_UNIT (decl) != 0 |
524 | && TREE_CODE (DECL_SIZE_UNIT (decl)) != INTEGER_CST) | |
525 | DECL_SIZE_UNIT (decl) = variable_size (DECL_SIZE_UNIT (decl)); | |
526 | ||
527 | /* If requested, warn about definitions of large data objects. */ | |
528 | if (warn_larger_than | |
17aec3eb | 529 | && (code == VAR_DECL || code == PARM_DECL) |
06ceef4e RK |
530 | && ! DECL_EXTERNAL (decl)) |
531 | { | |
532 | tree size = DECL_SIZE_UNIT (decl); | |
533 | ||
534 | if (size != 0 && TREE_CODE (size) == INTEGER_CST | |
05bccae2 | 535 | && compare_tree_int (size, larger_than_size) > 0) |
06ceef4e | 536 | { |
0384674e | 537 | int size_as_int = TREE_INT_CST_LOW (size); |
06ceef4e | 538 | |
05bccae2 | 539 | if (compare_tree_int (size, size_as_int) == 0) |
06ceef4e RK |
540 | warning_with_decl (decl, "size of `%s' is %d bytes", size_as_int); |
541 | else | |
542 | warning_with_decl (decl, "size of `%s' is larger than %d bytes", | |
543 | larger_than_size); | |
544 | } | |
545 | } | |
a46666a9 RH |
546 | |
547 | /* If the RTL was already set, update its mode and mem attributes. */ | |
548 | if (rtl) | |
549 | { | |
550 | PUT_MODE (rtl, DECL_MODE (decl)); | |
551 | SET_DECL_RTL (decl, 0); | |
552 | set_mem_attributes (rtl, decl, 1); | |
553 | SET_DECL_RTL (decl, rtl); | |
554 | } | |
7306ed3f JW |
555 | } |
556 | \f | |
e0cea8d9 RK |
557 | /* Hook for a front-end function that can modify the record layout as needed |
558 | immediately before it is finalized. */ | |
559 | ||
560 | void (*lang_adjust_rli) PARAMS ((record_layout_info)) = 0; | |
561 | ||
562 | void | |
563 | set_lang_adjust_rli (f) | |
564 | void (*f) PARAMS ((record_layout_info)); | |
565 | { | |
566 | lang_adjust_rli = f; | |
567 | } | |
568 | ||
770ae6cc RK |
569 | /* Begin laying out type T, which may be a RECORD_TYPE, UNION_TYPE, or |
570 | QUAL_UNION_TYPE. Return a pointer to a struct record_layout_info which | |
571 | is to be passed to all other layout functions for this record. It is the | |
786de7eb | 572 | responsibility of the caller to call `free' for the storage returned. |
770ae6cc RK |
573 | Note that garbage collection is not permitted until we finish laying |
574 | out the record. */ | |
7306ed3f | 575 | |
9328904c | 576 | record_layout_info |
770ae6cc | 577 | start_record_layout (t) |
9328904c | 578 | tree t; |
7306ed3f | 579 | { |
786de7eb | 580 | record_layout_info rli |
defd0dea | 581 | = (record_layout_info) xmalloc (sizeof (struct record_layout_info_s)); |
9328904c MM |
582 | |
583 | rli->t = t; | |
770ae6cc | 584 | |
9328904c MM |
585 | /* If the type has a minimum specified alignment (via an attribute |
586 | declaration, for example) use it -- otherwise, start with a | |
587 | one-byte alignment. */ | |
588 | rli->record_align = MAX (BITS_PER_UNIT, TYPE_ALIGN (t)); | |
78d55cc8 | 589 | rli->unpacked_align = rli->record_align; |
770ae6cc | 590 | rli->offset_align = MAX (rli->record_align, BIGGEST_ALIGNMENT); |
7306ed3f | 591 | |
5c19a356 MS |
592 | #ifdef STRUCTURE_SIZE_BOUNDARY |
593 | /* Packed structures don't need to have minimum size. */ | |
f132af85 | 594 | if (! TYPE_PACKED (t)) |
fc555370 | 595 | rli->record_align = MAX (rli->record_align, (unsigned) STRUCTURE_SIZE_BOUNDARY); |
5c19a356 | 596 | #endif |
7306ed3f | 597 | |
770ae6cc RK |
598 | rli->offset = size_zero_node; |
599 | rli->bitpos = bitsize_zero_node; | |
f913c102 | 600 | rli->prev_field = 0; |
770ae6cc RK |
601 | rli->pending_statics = 0; |
602 | rli->packed_maybe_necessary = 0; | |
603 | ||
9328904c MM |
604 | return rli; |
605 | } | |
7306ed3f | 606 | |
f2704b9f RK |
607 | /* These four routines perform computations that convert between |
608 | the offset/bitpos forms and byte and bit offsets. */ | |
609 | ||
610 | tree | |
611 | bit_from_pos (offset, bitpos) | |
612 | tree offset, bitpos; | |
613 | { | |
614 | return size_binop (PLUS_EXPR, bitpos, | |
615 | size_binop (MULT_EXPR, convert (bitsizetype, offset), | |
616 | bitsize_unit_node)); | |
617 | } | |
618 | ||
619 | tree | |
620 | byte_from_pos (offset, bitpos) | |
621 | tree offset, bitpos; | |
622 | { | |
623 | return size_binop (PLUS_EXPR, offset, | |
624 | convert (sizetype, | |
f0fddb15 | 625 | size_binop (TRUNC_DIV_EXPR, bitpos, |
f2704b9f RK |
626 | bitsize_unit_node))); |
627 | } | |
628 | ||
f2704b9f RK |
629 | void |
630 | pos_from_bit (poffset, pbitpos, off_align, pos) | |
631 | tree *poffset, *pbitpos; | |
632 | unsigned int off_align; | |
633 | tree pos; | |
634 | { | |
635 | *poffset = size_binop (MULT_EXPR, | |
636 | convert (sizetype, | |
637 | size_binop (FLOOR_DIV_EXPR, pos, | |
638 | bitsize_int (off_align))), | |
639 | size_int (off_align / BITS_PER_UNIT)); | |
640 | *pbitpos = size_binop (FLOOR_MOD_EXPR, pos, bitsize_int (off_align)); | |
641 | } | |
642 | ||
643 | /* Given a pointer to bit and byte offsets and an offset alignment, | |
644 | normalize the offsets so they are within the alignment. */ | |
645 | ||
646 | void | |
647 | normalize_offset (poffset, pbitpos, off_align) | |
648 | tree *poffset, *pbitpos; | |
649 | unsigned int off_align; | |
650 | { | |
651 | /* If the bit position is now larger than it should be, adjust it | |
652 | downwards. */ | |
653 | if (compare_tree_int (*pbitpos, off_align) >= 0) | |
654 | { | |
655 | tree extra_aligns = size_binop (FLOOR_DIV_EXPR, *pbitpos, | |
656 | bitsize_int (off_align)); | |
657 | ||
658 | *poffset | |
659 | = size_binop (PLUS_EXPR, *poffset, | |
660 | size_binop (MULT_EXPR, convert (sizetype, extra_aligns), | |
661 | size_int (off_align / BITS_PER_UNIT))); | |
786de7eb | 662 | |
f2704b9f RK |
663 | *pbitpos |
664 | = size_binop (FLOOR_MOD_EXPR, *pbitpos, bitsize_int (off_align)); | |
665 | } | |
666 | } | |
667 | ||
770ae6cc | 668 | /* Print debugging information about the information in RLI. */ |
cc9d4a85 | 669 | |
770ae6cc RK |
670 | void |
671 | debug_rli (rli) | |
cc9d4a85 | 672 | record_layout_info rli; |
cc9d4a85 | 673 | { |
770ae6cc RK |
674 | print_node_brief (stderr, "type", rli->t, 0); |
675 | print_node_brief (stderr, "\noffset", rli->offset, 0); | |
676 | print_node_brief (stderr, " bitpos", rli->bitpos, 0); | |
cc9d4a85 | 677 | |
78d55cc8 JM |
678 | fprintf (stderr, "\naligns: rec = %u, unpack = %u, off = %u\n", |
679 | rli->record_align, rli->unpacked_align, | |
e0cea8d9 | 680 | rli->offset_align); |
770ae6cc RK |
681 | if (rli->packed_maybe_necessary) |
682 | fprintf (stderr, "packed may be necessary\n"); | |
683 | ||
684 | if (rli->pending_statics) | |
685 | { | |
686 | fprintf (stderr, "pending statics:\n"); | |
687 | debug_tree (rli->pending_statics); | |
688 | } | |
689 | } | |
690 | ||
691 | /* Given an RLI with a possibly-incremented BITPOS, adjust OFFSET and | |
692 | BITPOS if necessary to keep BITPOS below OFFSET_ALIGN. */ | |
693 | ||
694 | void | |
695 | normalize_rli (rli) | |
696 | record_layout_info rli; | |
697 | { | |
f2704b9f | 698 | normalize_offset (&rli->offset, &rli->bitpos, rli->offset_align); |
770ae6cc | 699 | } |
cc9d4a85 | 700 | |
770ae6cc RK |
701 | /* Returns the size in bytes allocated so far. */ |
702 | ||
703 | tree | |
704 | rli_size_unit_so_far (rli) | |
705 | record_layout_info rli; | |
706 | { | |
f2704b9f | 707 | return byte_from_pos (rli->offset, rli->bitpos); |
770ae6cc RK |
708 | } |
709 | ||
710 | /* Returns the size in bits allocated so far. */ | |
711 | ||
712 | tree | |
713 | rli_size_so_far (rli) | |
714 | record_layout_info rli; | |
715 | { | |
f2704b9f | 716 | return bit_from_pos (rli->offset, rli->bitpos); |
770ae6cc RK |
717 | } |
718 | ||
0645ba8f MM |
719 | /* FIELD is about to be added to RLI->T. The alignment (in bits) of |
720 | the next available location is given by KNOWN_ALIGN. Update the | |
721 | variable alignment fields in RLI, and return the alignment to give | |
722 | the FIELD. */ | |
770ae6cc | 723 | |
0645ba8f MM |
724 | static unsigned int |
725 | update_alignment_for_field (rli, field, known_align) | |
9328904c MM |
726 | record_layout_info rli; |
727 | tree field; | |
0645ba8f | 728 | unsigned int known_align; |
9328904c MM |
729 | { |
730 | /* The alignment required for FIELD. */ | |
731 | unsigned int desired_align; | |
9328904c MM |
732 | /* The type of this field. */ |
733 | tree type = TREE_TYPE (field); | |
0645ba8f MM |
734 | /* True if the field was explicitly aligned by the user. */ |
735 | bool user_align; | |
78d55cc8 | 736 | bool is_bitfield; |
9328904c | 737 | |
78d55cc8 JM |
738 | /* Lay out the field so we know what alignment it needs. */ |
739 | layout_decl (field, known_align); | |
770ae6cc | 740 | desired_align = DECL_ALIGN (field); |
11cf4d18 | 741 | user_align = DECL_USER_ALIGN (field); |
770ae6cc | 742 | |
78d55cc8 JM |
743 | is_bitfield = (type != error_mark_node |
744 | && DECL_BIT_FIELD_TYPE (field) | |
745 | && ! integer_zerop (TYPE_SIZE (type))); | |
7306ed3f | 746 | |
9328904c MM |
747 | /* Record must have at least as much alignment as any field. |
748 | Otherwise, the alignment of the field within the record is | |
749 | meaningless. */ | |
78d55cc8 | 750 | if (is_bitfield && (* targetm.ms_bitfield_layout_p) (rli->t)) |
f913c102 | 751 | { |
e4850f36 DR |
752 | /* Here, the alignment of the underlying type of a bitfield can |
753 | affect the alignment of a record; even a zero-sized field | |
754 | can do this. The alignment should be to the alignment of | |
755 | the type, except that for zero-size bitfields this only | |
0e9e1e0a | 756 | applies if there was an immediately prior, nonzero-size |
e4850f36 DR |
757 | bitfield. (That's the way it is, experimentally.) */ |
758 | if (! integer_zerop (DECL_SIZE (field)) | |
759 | ? ! DECL_PACKED (field) | |
760 | : (rli->prev_field | |
761 | && DECL_BIT_FIELD_TYPE (rli->prev_field) | |
762 | && ! integer_zerop (DECL_SIZE (rli->prev_field)))) | |
f913c102 | 763 | { |
e4850f36 DR |
764 | unsigned int type_align = TYPE_ALIGN (type); |
765 | type_align = MAX (type_align, desired_align); | |
766 | if (maximum_field_alignment != 0) | |
767 | type_align = MIN (type_align, maximum_field_alignment); | |
768 | rli->record_align = MAX (rli->record_align, type_align); | |
f913c102 AO |
769 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
770 | } | |
786de7eb | 771 | } |
3c12fcc2 | 772 | #ifdef PCC_BITFIELD_TYPE_MATTERS |
78d55cc8 | 773 | else if (is_bitfield && PCC_BITFIELD_TYPE_MATTERS) |
9328904c | 774 | { |
8dc65b6e MM |
775 | /* Named bit-fields cause the entire structure to have the |
776 | alignment implied by their type. */ | |
9328904c | 777 | if (DECL_NAME (field) != 0) |
7306ed3f | 778 | { |
9328904c | 779 | unsigned int type_align = TYPE_ALIGN (type); |
729a2125 | 780 | |
ad9335eb JJ |
781 | #ifdef ADJUST_FIELD_ALIGN |
782 | if (! TYPE_USER_ALIGN (type)) | |
783 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
784 | #endif | |
785 | ||
9328904c MM |
786 | if (maximum_field_alignment != 0) |
787 | type_align = MIN (type_align, maximum_field_alignment); | |
788 | else if (DECL_PACKED (field)) | |
789 | type_align = MIN (type_align, BITS_PER_UNIT); | |
e2301a83 | 790 | |
8dc65b6e MM |
791 | /* The alignment of the record is increased to the maximum |
792 | of the current alignment, the alignment indicated on the | |
793 | field (i.e., the alignment specified by an __aligned__ | |
794 | attribute), and the alignment indicated by the type of | |
795 | the field. */ | |
796 | rli->record_align = MAX (rli->record_align, desired_align); | |
9328904c | 797 | rli->record_align = MAX (rli->record_align, type_align); |
8dc65b6e | 798 | |
3c12fcc2 | 799 | if (warn_packed) |
e0cea8d9 | 800 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
daf06049 | 801 | user_align |= TYPE_USER_ALIGN (type); |
3c12fcc2 | 802 | } |
9328904c | 803 | } |
9328904c | 804 | #endif |
78d55cc8 | 805 | else |
9328904c MM |
806 | { |
807 | rli->record_align = MAX (rli->record_align, desired_align); | |
770ae6cc | 808 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
9328904c | 809 | } |
3c12fcc2 | 810 | |
0645ba8f MM |
811 | TYPE_USER_ALIGN (rli->t) |= user_align; |
812 | ||
813 | return desired_align; | |
814 | } | |
815 | ||
816 | /* Called from place_field to handle unions. */ | |
817 | ||
818 | static void | |
819 | place_union_field (rli, field) | |
820 | record_layout_info rli; | |
821 | tree field; | |
822 | { | |
823 | update_alignment_for_field (rli, field, /*known_align=*/0); | |
824 | ||
825 | DECL_FIELD_OFFSET (field) = size_zero_node; | |
826 | DECL_FIELD_BIT_OFFSET (field) = bitsize_zero_node; | |
827 | SET_DECL_OFFSET_ALIGN (field, BIGGEST_ALIGNMENT); | |
828 | ||
829 | /* We assume the union's size will be a multiple of a byte so we don't | |
830 | bother with BITPOS. */ | |
831 | if (TREE_CODE (rli->t) == UNION_TYPE) | |
832 | rli->offset = size_binop (MAX_EXPR, rli->offset, DECL_SIZE_UNIT (field)); | |
833 | else if (TREE_CODE (rli->t) == QUAL_UNION_TYPE) | |
834 | rli->offset = fold (build (COND_EXPR, sizetype, | |
835 | DECL_QUALIFIER (field), | |
836 | DECL_SIZE_UNIT (field), rli->offset)); | |
837 | } | |
838 | ||
b8089d8d | 839 | #if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED) |
4977bab6 | 840 | /* A bitfield of SIZE with a required access alignment of ALIGN is allocated |
272d0bee | 841 | at BYTE_OFFSET / BIT_OFFSET. Return nonzero if the field would span more |
4977bab6 ZW |
842 | units of alignment than the underlying TYPE. */ |
843 | static int | |
844 | excess_unit_span (byte_offset, bit_offset, size, align, type) | |
845 | HOST_WIDE_INT byte_offset, bit_offset, size, align; | |
846 | tree type; | |
847 | { | |
848 | /* Note that the calculation of OFFSET might overflow; we calculate it so | |
849 | that we still get the right result as long as ALIGN is a power of two. */ | |
850 | unsigned HOST_WIDE_INT offset = byte_offset * BITS_PER_UNIT + bit_offset; | |
851 | ||
852 | offset = offset % align; | |
853 | return ((offset + size + align - 1) / align | |
854 | > ((unsigned HOST_WIDE_INT) tree_low_cst (TYPE_SIZE (type), 1) | |
855 | / align)); | |
856 | } | |
b8089d8d | 857 | #endif |
4977bab6 | 858 | |
0645ba8f MM |
859 | /* RLI contains information about the layout of a RECORD_TYPE. FIELD |
860 | is a FIELD_DECL to be added after those fields already present in | |
861 | T. (FIELD is not actually added to the TYPE_FIELDS list here; | |
862 | callers that desire that behavior must manually perform that step.) */ | |
863 | ||
864 | void | |
865 | place_field (rli, field) | |
866 | record_layout_info rli; | |
867 | tree field; | |
868 | { | |
869 | /* The alignment required for FIELD. */ | |
870 | unsigned int desired_align; | |
871 | /* The alignment FIELD would have if we just dropped it into the | |
872 | record as it presently stands. */ | |
873 | unsigned int known_align; | |
874 | unsigned int actual_align; | |
875 | /* The type of this field. */ | |
876 | tree type = TREE_TYPE (field); | |
877 | ||
878 | if (TREE_CODE (field) == ERROR_MARK || TREE_CODE (type) == ERROR_MARK) | |
879 | return; | |
880 | ||
881 | /* If FIELD is static, then treat it like a separate variable, not | |
882 | really like a structure field. If it is a FUNCTION_DECL, it's a | |
883 | method. In both cases, all we do is lay out the decl, and we do | |
884 | it *after* the record is laid out. */ | |
885 | if (TREE_CODE (field) == VAR_DECL) | |
886 | { | |
887 | rli->pending_statics = tree_cons (NULL_TREE, field, | |
888 | rli->pending_statics); | |
889 | return; | |
890 | } | |
891 | ||
892 | /* Enumerators and enum types which are local to this class need not | |
893 | be laid out. Likewise for initialized constant fields. */ | |
894 | else if (TREE_CODE (field) != FIELD_DECL) | |
895 | return; | |
896 | ||
897 | /* Unions are laid out very differently than records, so split | |
898 | that code off to another function. */ | |
899 | else if (TREE_CODE (rli->t) != RECORD_TYPE) | |
900 | { | |
901 | place_union_field (rli, field); | |
902 | return; | |
903 | } | |
904 | ||
905 | /* Work out the known alignment so far. Note that A & (-A) is the | |
906 | value of the least-significant bit in A that is one. */ | |
907 | if (! integer_zerop (rli->bitpos)) | |
908 | known_align = (tree_low_cst (rli->bitpos, 1) | |
909 | & - tree_low_cst (rli->bitpos, 1)); | |
910 | else if (integer_zerop (rli->offset)) | |
911 | known_align = BIGGEST_ALIGNMENT; | |
912 | else if (host_integerp (rli->offset, 1)) | |
913 | known_align = (BITS_PER_UNIT | |
914 | * (tree_low_cst (rli->offset, 1) | |
915 | & - tree_low_cst (rli->offset, 1))); | |
916 | else | |
917 | known_align = rli->offset_align; | |
918 | ||
919 | desired_align = update_alignment_for_field (rli, field, known_align); | |
920 | ||
9328904c MM |
921 | if (warn_packed && DECL_PACKED (field)) |
922 | { | |
78d55cc8 | 923 | if (known_align >= TYPE_ALIGN (type)) |
3c12fcc2 | 924 | { |
9328904c | 925 | if (TYPE_ALIGN (type) > desired_align) |
3c12fcc2 | 926 | { |
9328904c MM |
927 | if (STRICT_ALIGNMENT) |
928 | warning_with_decl (field, "packed attribute causes inefficient alignment for `%s'"); | |
929 | else | |
930 | warning_with_decl (field, "packed attribute is unnecessary for `%s'"); | |
3c12fcc2 | 931 | } |
3c12fcc2 | 932 | } |
9328904c MM |
933 | else |
934 | rli->packed_maybe_necessary = 1; | |
935 | } | |
7306ed3f | 936 | |
9328904c MM |
937 | /* Does this field automatically have alignment it needs by virtue |
938 | of the fields that precede it and the record's own alignment? */ | |
770ae6cc | 939 | if (known_align < desired_align) |
9328904c MM |
940 | { |
941 | /* No, we need to skip space before this field. | |
942 | Bump the cumulative size to multiple of field alignment. */ | |
7306ed3f | 943 | |
9328904c MM |
944 | if (warn_padded) |
945 | warning_with_decl (field, "padding struct to align `%s'"); | |
3c12fcc2 | 946 | |
770ae6cc RK |
947 | /* If the alignment is still within offset_align, just align |
948 | the bit position. */ | |
949 | if (desired_align < rli->offset_align) | |
950 | rli->bitpos = round_up (rli->bitpos, desired_align); | |
9328904c MM |
951 | else |
952 | { | |
770ae6cc RK |
953 | /* First adjust OFFSET by the partial bits, then align. */ |
954 | rli->offset | |
955 | = size_binop (PLUS_EXPR, rli->offset, | |
956 | convert (sizetype, | |
957 | size_binop (CEIL_DIV_EXPR, rli->bitpos, | |
958 | bitsize_unit_node))); | |
959 | rli->bitpos = bitsize_zero_node; | |
960 | ||
961 | rli->offset = round_up (rli->offset, desired_align / BITS_PER_UNIT); | |
7306ed3f | 962 | } |
770ae6cc | 963 | |
b1254b72 RK |
964 | if (! TREE_CONSTANT (rli->offset)) |
965 | rli->offset_align = desired_align; | |
966 | ||
9328904c | 967 | } |
7306ed3f | 968 | |
770ae6cc RK |
969 | /* Handle compatibility with PCC. Note that if the record has any |
970 | variable-sized fields, we need not worry about compatibility. */ | |
7306ed3f | 971 | #ifdef PCC_BITFIELD_TYPE_MATTERS |
9328904c | 972 | if (PCC_BITFIELD_TYPE_MATTERS |
f913c102 | 973 | && ! (* targetm.ms_bitfield_layout_p) (rli->t) |
9328904c MM |
974 | && TREE_CODE (field) == FIELD_DECL |
975 | && type != error_mark_node | |
770ae6cc RK |
976 | && DECL_BIT_FIELD (field) |
977 | && ! DECL_PACKED (field) | |
9328904c | 978 | && maximum_field_alignment == 0 |
770ae6cc RK |
979 | && ! integer_zerop (DECL_SIZE (field)) |
980 | && host_integerp (DECL_SIZE (field), 1) | |
981 | && host_integerp (rli->offset, 1) | |
982 | && host_integerp (TYPE_SIZE (type), 1)) | |
9328904c MM |
983 | { |
984 | unsigned int type_align = TYPE_ALIGN (type); | |
770ae6cc RK |
985 | tree dsize = DECL_SIZE (field); |
986 | HOST_WIDE_INT field_size = tree_low_cst (dsize, 1); | |
987 | HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0); | |
988 | HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0); | |
9328904c | 989 | |
ad9335eb JJ |
990 | #ifdef ADJUST_FIELD_ALIGN |
991 | if (! TYPE_USER_ALIGN (type)) | |
992 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
993 | #endif | |
994 | ||
9328904c MM |
995 | /* A bit field may not span more units of alignment of its type |
996 | than its type itself. Advance to next boundary if necessary. */ | |
4977bab6 | 997 | if (excess_unit_span (offset, bit_offset, field_size, type_align, type)) |
770ae6cc | 998 | rli->bitpos = round_up (rli->bitpos, type_align); |
daf06049 | 999 | |
0645ba8f | 1000 | TYPE_USER_ALIGN (rli->t) |= TYPE_USER_ALIGN (type); |
9328904c | 1001 | } |
7306ed3f JW |
1002 | #endif |
1003 | ||
7306ed3f | 1004 | #ifdef BITFIELD_NBYTES_LIMITED |
9328904c | 1005 | if (BITFIELD_NBYTES_LIMITED |
f913c102 | 1006 | && ! (* targetm.ms_bitfield_layout_p) (rli->t) |
9328904c MM |
1007 | && TREE_CODE (field) == FIELD_DECL |
1008 | && type != error_mark_node | |
1009 | && DECL_BIT_FIELD_TYPE (field) | |
770ae6cc RK |
1010 | && ! DECL_PACKED (field) |
1011 | && ! integer_zerop (DECL_SIZE (field)) | |
1012 | && host_integerp (DECL_SIZE (field), 1) | |
163d3408 | 1013 | && host_integerp (rli->offset, 1) |
770ae6cc | 1014 | && host_integerp (TYPE_SIZE (type), 1)) |
9328904c MM |
1015 | { |
1016 | unsigned int type_align = TYPE_ALIGN (type); | |
770ae6cc RK |
1017 | tree dsize = DECL_SIZE (field); |
1018 | HOST_WIDE_INT field_size = tree_low_cst (dsize, 1); | |
1019 | HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0); | |
1020 | HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0); | |
e2301a83 | 1021 | |
ad9335eb JJ |
1022 | #ifdef ADJUST_FIELD_ALIGN |
1023 | if (! TYPE_USER_ALIGN (type)) | |
1024 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
1025 | #endif | |
1026 | ||
9328904c MM |
1027 | if (maximum_field_alignment != 0) |
1028 | type_align = MIN (type_align, maximum_field_alignment); | |
1029 | /* ??? This test is opposite the test in the containing if | |
1030 | statement, so this code is unreachable currently. */ | |
1031 | else if (DECL_PACKED (field)) | |
1032 | type_align = MIN (type_align, BITS_PER_UNIT); | |
1033 | ||
1034 | /* A bit field may not span the unit of alignment of its type. | |
1035 | Advance to next boundary if necessary. */ | |
4977bab6 | 1036 | if (excess_unit_span (offset, bit_offset, field_size, type_align, type)) |
770ae6cc | 1037 | rli->bitpos = round_up (rli->bitpos, type_align); |
daf06049 | 1038 | |
0645ba8f | 1039 | TYPE_USER_ALIGN (rli->t) |= TYPE_USER_ALIGN (type); |
9328904c | 1040 | } |
7306ed3f JW |
1041 | #endif |
1042 | ||
e4850f36 DR |
1043 | /* See the docs for TARGET_MS_BITFIELD_LAYOUT_P for details. |
1044 | A subtlety: | |
1045 | When a bit field is inserted into a packed record, the whole | |
1046 | size of the underlying type is used by one or more same-size | |
4977bab6 | 1047 | adjacent bitfields. (That is, if its long:3, 32 bits is |
e4850f36 DR |
1048 | used in the record, and any additional adjacent long bitfields are |
1049 | packed into the same chunk of 32 bits. However, if the size | |
1050 | changes, a new field of that size is allocated.) In an unpacked | |
14b493d6 | 1051 | record, this is the same as using alignment, but not equivalent |
4977bab6 | 1052 | when packing. |
e4850f36 | 1053 | |
14b493d6 | 1054 | Note: for compatibility, we use the type size, not the type alignment |
e4850f36 DR |
1055 | to determine alignment, since that matches the documentation */ |
1056 | ||
f913c102 | 1057 | if ((* targetm.ms_bitfield_layout_p) (rli->t) |
e4850f36 DR |
1058 | && ((DECL_BIT_FIELD_TYPE (field) && ! DECL_PACKED (field)) |
1059 | || (rli->prev_field && ! DECL_PACKED (rli->prev_field)))) | |
f913c102 | 1060 | { |
e4850f36 | 1061 | /* At this point, either the prior or current are bitfields, |
991b6592 | 1062 | (possibly both), and we're dealing with MS packing. */ |
e4850f36 | 1063 | tree prev_saved = rli->prev_field; |
f913c102 | 1064 | |
e4850f36 | 1065 | /* Is the prior field a bitfield? If so, handle "runs" of same |
991b6592 KH |
1066 | type size fields. */ |
1067 | if (rli->prev_field /* necessarily a bitfield if it exists. */) | |
e4850f36 DR |
1068 | { |
1069 | /* If both are bitfields, nonzero, and the same size, this is | |
1070 | the middle of a run. Zero declared size fields are special | |
1071 | and handled as "end of run". (Note: it's nonzero declared | |
1072 | size, but equal type sizes!) (Since we know that both | |
1073 | the current and previous fields are bitfields by the | |
1074 | time we check it, DECL_SIZE must be present for both.) */ | |
1075 | if (DECL_BIT_FIELD_TYPE (field) | |
1076 | && !integer_zerop (DECL_SIZE (field)) | |
1077 | && !integer_zerop (DECL_SIZE (rli->prev_field)) | |
0384674e RK |
1078 | && host_integerp (DECL_SIZE (rli->prev_field), 0) |
1079 | && host_integerp (TYPE_SIZE (type), 0) | |
e4850f36 | 1080 | && simple_cst_equal (TYPE_SIZE (type), |
0384674e | 1081 | TYPE_SIZE (TREE_TYPE (rli->prev_field)))) |
e4850f36 DR |
1082 | { |
1083 | /* We're in the middle of a run of equal type size fields; make | |
1084 | sure we realign if we run out of bits. (Not decl size, | |
1085 | type size!) */ | |
0384674e | 1086 | HOST_WIDE_INT bitsize = tree_low_cst (DECL_SIZE (field), 0); |
e4850f36 DR |
1087 | |
1088 | if (rli->remaining_in_alignment < bitsize) | |
1089 | { | |
991b6592 | 1090 | /* out of bits; bump up to next 'word'. */ |
5354730b | 1091 | rli->offset = DECL_FIELD_OFFSET (rli->prev_field); |
0384674e RK |
1092 | rli->bitpos |
1093 | = size_binop (PLUS_EXPR, TYPE_SIZE (type), | |
1094 | DECL_FIELD_BIT_OFFSET (rli->prev_field)); | |
e4850f36 | 1095 | rli->prev_field = field; |
0384674e RK |
1096 | rli->remaining_in_alignment |
1097 | = tree_low_cst (TYPE_SIZE (type), 0); | |
e4850f36 | 1098 | } |
0384674e | 1099 | |
e4850f36 DR |
1100 | rli->remaining_in_alignment -= bitsize; |
1101 | } | |
1102 | else | |
1103 | { | |
4977bab6 ZW |
1104 | /* End of a run: if leaving a run of bitfields of the same type |
1105 | size, we have to "use up" the rest of the bits of the type | |
e4850f36 DR |
1106 | size. |
1107 | ||
1108 | Compute the new position as the sum of the size for the prior | |
1109 | type and where we first started working on that type. | |
1110 | Note: since the beginning of the field was aligned then | |
1111 | of course the end will be too. No round needed. */ | |
1112 | ||
1113 | if (!integer_zerop (DECL_SIZE (rli->prev_field))) | |
1114 | { | |
0384674e RK |
1115 | tree type_size = TYPE_SIZE (TREE_TYPE (rli->prev_field)); |
1116 | ||
1117 | rli->bitpos | |
1118 | = size_binop (PLUS_EXPR, type_size, | |
1119 | DECL_FIELD_BIT_OFFSET (rli->prev_field)); | |
e4850f36 DR |
1120 | } |
1121 | else | |
0384674e RK |
1122 | /* We "use up" size zero fields; the code below should behave |
1123 | as if the prior field was not a bitfield. */ | |
1124 | prev_saved = NULL; | |
e4850f36 | 1125 | |
4977bab6 | 1126 | /* Cause a new bitfield to be captured, either this time (if |
991b6592 | 1127 | currently a bitfield) or next time we see one. */ |
e4850f36 DR |
1128 | if (!DECL_BIT_FIELD_TYPE(field) |
1129 | || integer_zerop (DECL_SIZE (field))) | |
0384674e | 1130 | rli->prev_field = NULL; |
e4850f36 | 1131 | } |
0384674e | 1132 | |
e4850f36 DR |
1133 | normalize_rli (rli); |
1134 | } | |
1135 | ||
1136 | /* If we're starting a new run of same size type bitfields | |
1137 | (or a run of non-bitfields), set up the "first of the run" | |
4977bab6 | 1138 | fields. |
e4850f36 DR |
1139 | |
1140 | That is, if the current field is not a bitfield, or if there | |
1141 | was a prior bitfield the type sizes differ, or if there wasn't | |
1142 | a prior bitfield the size of the current field is nonzero. | |
1143 | ||
1144 | Note: we must be sure to test ONLY the type size if there was | |
1145 | a prior bitfield and ONLY for the current field being zero if | |
1146 | there wasn't. */ | |
1147 | ||
1148 | if (!DECL_BIT_FIELD_TYPE (field) | |
4977bab6 | 1149 | || ( prev_saved != NULL |
e4850f36 | 1150 | ? !simple_cst_equal (TYPE_SIZE (type), |
0384674e RK |
1151 | TYPE_SIZE (TREE_TYPE (prev_saved))) |
1152 | : !integer_zerop (DECL_SIZE (field)) )) | |
e4850f36 | 1153 | { |
0384674e RK |
1154 | /* Never smaller than a byte for compatibility. */ |
1155 | unsigned int type_align = BITS_PER_UNIT; | |
e4850f36 | 1156 | |
4977bab6 | 1157 | /* (When not a bitfield), we could be seeing a flex array (with |
e4850f36 | 1158 | no DECL_SIZE). Since we won't be using remaining_in_alignment |
4977bab6 | 1159 | until we see a bitfield (and come by here again) we just skip |
e4850f36 | 1160 | calculating it. */ |
0384674e RK |
1161 | if (DECL_SIZE (field) != NULL |
1162 | && host_integerp (TYPE_SIZE (TREE_TYPE (field)), 0) | |
1163 | && host_integerp (DECL_SIZE (field), 0)) | |
1164 | rli->remaining_in_alignment | |
1165 | = tree_low_cst (TYPE_SIZE (TREE_TYPE(field)), 0) | |
1166 | - tree_low_cst (DECL_SIZE (field), 0); | |
e4850f36 | 1167 | |
991b6592 | 1168 | /* Now align (conventionally) for the new type. */ |
e4850f36 | 1169 | if (!DECL_PACKED(field)) |
0384674e | 1170 | type_align = MAX(TYPE_ALIGN (type), type_align); |
e4850f36 DR |
1171 | |
1172 | if (prev_saved | |
1173 | && DECL_BIT_FIELD_TYPE (prev_saved) | |
1174 | /* If the previous bit-field is zero-sized, we've already | |
1175 | accounted for its alignment needs (or ignored it, if | |
1176 | appropriate) while placing it. */ | |
1177 | && ! integer_zerop (DECL_SIZE (prev_saved))) | |
1178 | type_align = MAX (type_align, | |
1179 | TYPE_ALIGN (TREE_TYPE (prev_saved))); | |
f913c102 | 1180 | |
e4850f36 DR |
1181 | if (maximum_field_alignment != 0) |
1182 | type_align = MIN (type_align, maximum_field_alignment); | |
f913c102 | 1183 | |
e4850f36 | 1184 | rli->bitpos = round_up (rli->bitpos, type_align); |
0384674e | 1185 | |
e4850f36 | 1186 | /* If we really aligned, don't allow subsequent bitfields |
991b6592 | 1187 | to undo that. */ |
e4850f36 DR |
1188 | rli->prev_field = NULL; |
1189 | } | |
f913c102 AO |
1190 | } |
1191 | ||
770ae6cc RK |
1192 | /* Offset so far becomes the position of this field after normalizing. */ |
1193 | normalize_rli (rli); | |
1194 | DECL_FIELD_OFFSET (field) = rli->offset; | |
1195 | DECL_FIELD_BIT_OFFSET (field) = rli->bitpos; | |
2f5c7f45 | 1196 | SET_DECL_OFFSET_ALIGN (field, rli->offset_align); |
770ae6cc RK |
1197 | |
1198 | /* If this field ended up more aligned than we thought it would be (we | |
1199 | approximate this by seeing if its position changed), lay out the field | |
1200 | again; perhaps we can use an integral mode for it now. */ | |
4b6bf620 | 1201 | if (! integer_zerop (DECL_FIELD_BIT_OFFSET (field))) |
770ae6cc RK |
1202 | actual_align = (tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1) |
1203 | & - tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1)); | |
4b6bf620 RK |
1204 | else if (integer_zerop (DECL_FIELD_OFFSET (field))) |
1205 | actual_align = BIGGEST_ALIGNMENT; | |
770ae6cc RK |
1206 | else if (host_integerp (DECL_FIELD_OFFSET (field), 1)) |
1207 | actual_align = (BITS_PER_UNIT | |
1208 | * (tree_low_cst (DECL_FIELD_OFFSET (field), 1) | |
1209 | & - tree_low_cst (DECL_FIELD_OFFSET (field), 1))); | |
9328904c | 1210 | else |
770ae6cc RK |
1211 | actual_align = DECL_OFFSET_ALIGN (field); |
1212 | ||
1213 | if (known_align != actual_align) | |
1214 | layout_decl (field, actual_align); | |
1215 | ||
991b6592 | 1216 | /* Only the MS bitfields use this. */ |
e4850f36 DR |
1217 | if (rli->prev_field == NULL && DECL_BIT_FIELD_TYPE(field)) |
1218 | rli->prev_field = field; | |
f913c102 | 1219 | |
770ae6cc RK |
1220 | /* Now add size of this field to the size of the record. If the size is |
1221 | not constant, treat the field as being a multiple of bytes and just | |
1222 | adjust the offset, resetting the bit position. Otherwise, apportion the | |
1223 | size amongst the bit position and offset. First handle the case of an | |
1224 | unspecified size, which can happen when we have an invalid nested struct | |
1225 | definition, such as struct j { struct j { int i; } }. The error message | |
1226 | is printed in finish_struct. */ | |
1227 | if (DECL_SIZE (field) == 0) | |
1228 | /* Do nothing. */; | |
67011d81 RK |
1229 | else if (TREE_CODE (DECL_SIZE_UNIT (field)) != INTEGER_CST |
1230 | || TREE_CONSTANT_OVERFLOW (DECL_SIZE_UNIT (field))) | |
9328904c | 1231 | { |
770ae6cc RK |
1232 | rli->offset |
1233 | = size_binop (PLUS_EXPR, rli->offset, | |
1234 | convert (sizetype, | |
1235 | size_binop (CEIL_DIV_EXPR, rli->bitpos, | |
1236 | bitsize_unit_node))); | |
1237 | rli->offset | |
1238 | = size_binop (PLUS_EXPR, rli->offset, DECL_SIZE_UNIT (field)); | |
1239 | rli->bitpos = bitsize_zero_node; | |
3923e410 | 1240 | rli->offset_align = MIN (rli->offset_align, desired_align); |
9328904c | 1241 | } |
9328904c MM |
1242 | else |
1243 | { | |
770ae6cc RK |
1244 | rli->bitpos = size_binop (PLUS_EXPR, rli->bitpos, DECL_SIZE (field)); |
1245 | normalize_rli (rli); | |
7306ed3f | 1246 | } |
9328904c | 1247 | } |
7306ed3f | 1248 | |
9328904c MM |
1249 | /* Assuming that all the fields have been laid out, this function uses |
1250 | RLI to compute the final TYPE_SIZE, TYPE_ALIGN, etc. for the type | |
14b493d6 | 1251 | indicated by RLI. */ |
7306ed3f | 1252 | |
9328904c MM |
1253 | static void |
1254 | finalize_record_size (rli) | |
1255 | record_layout_info rli; | |
1256 | { | |
770ae6cc RK |
1257 | tree unpadded_size, unpadded_size_unit; |
1258 | ||
65e14bf5 RK |
1259 | /* Now we want just byte and bit offsets, so set the offset alignment |
1260 | to be a byte and then normalize. */ | |
1261 | rli->offset_align = BITS_PER_UNIT; | |
1262 | normalize_rli (rli); | |
7306ed3f JW |
1263 | |
1264 | /* Determine the desired alignment. */ | |
1265 | #ifdef ROUND_TYPE_ALIGN | |
9328904c | 1266 | TYPE_ALIGN (rli->t) = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t), |
b451555a | 1267 | rli->record_align); |
7306ed3f | 1268 | #else |
9328904c | 1269 | TYPE_ALIGN (rli->t) = MAX (TYPE_ALIGN (rli->t), rli->record_align); |
7306ed3f JW |
1270 | #endif |
1271 | ||
65e14bf5 RK |
1272 | /* Compute the size so far. Be sure to allow for extra bits in the |
1273 | size in bytes. We have guaranteed above that it will be no more | |
1274 | than a single byte. */ | |
1275 | unpadded_size = rli_size_so_far (rli); | |
1276 | unpadded_size_unit = rli_size_unit_so_far (rli); | |
1277 | if (! integer_zerop (rli->bitpos)) | |
1278 | unpadded_size_unit | |
1279 | = size_binop (PLUS_EXPR, unpadded_size_unit, size_one_node); | |
770ae6cc | 1280 | |
1824b90d | 1281 | /* Round the size up to be a multiple of the required alignment */ |
770ae6cc RK |
1282 | TYPE_SIZE (rli->t) = round_up (unpadded_size, TYPE_ALIGN (rli->t)); |
1283 | TYPE_SIZE_UNIT (rli->t) = round_up (unpadded_size_unit, | |
1284 | TYPE_ALIGN (rli->t) / BITS_PER_UNIT); | |
729a2125 | 1285 | |
770ae6cc RK |
1286 | if (warn_padded && TREE_CONSTANT (unpadded_size) |
1287 | && simple_cst_equal (unpadded_size, TYPE_SIZE (rli->t)) == 0) | |
1288 | warning ("padding struct size to alignment boundary"); | |
786de7eb | 1289 | |
770ae6cc RK |
1290 | if (warn_packed && TREE_CODE (rli->t) == RECORD_TYPE |
1291 | && TYPE_PACKED (rli->t) && ! rli->packed_maybe_necessary | |
1292 | && TREE_CONSTANT (unpadded_size)) | |
3c12fcc2 GM |
1293 | { |
1294 | tree unpacked_size; | |
729a2125 | 1295 | |
3c12fcc2 | 1296 | #ifdef ROUND_TYPE_ALIGN |
9328904c MM |
1297 | rli->unpacked_align |
1298 | = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t), rli->unpacked_align); | |
3c12fcc2 | 1299 | #else |
9328904c | 1300 | rli->unpacked_align = MAX (TYPE_ALIGN (rli->t), rli->unpacked_align); |
3c12fcc2 | 1301 | #endif |
770ae6cc | 1302 | |
9328904c | 1303 | unpacked_size = round_up (TYPE_SIZE (rli->t), rli->unpacked_align); |
9328904c | 1304 | if (simple_cst_equal (unpacked_size, TYPE_SIZE (rli->t))) |
3c12fcc2 | 1305 | { |
770ae6cc RK |
1306 | TYPE_PACKED (rli->t) = 0; |
1307 | ||
9328904c | 1308 | if (TYPE_NAME (rli->t)) |
3c12fcc2 | 1309 | { |
63ad61ed | 1310 | const char *name; |
729a2125 | 1311 | |
9328904c MM |
1312 | if (TREE_CODE (TYPE_NAME (rli->t)) == IDENTIFIER_NODE) |
1313 | name = IDENTIFIER_POINTER (TYPE_NAME (rli->t)); | |
3c12fcc2 | 1314 | else |
9328904c | 1315 | name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (rli->t))); |
770ae6cc | 1316 | |
3c12fcc2 GM |
1317 | if (STRICT_ALIGNMENT) |
1318 | warning ("packed attribute causes inefficient alignment for `%s'", name); | |
1319 | else | |
1320 | warning ("packed attribute is unnecessary for `%s'", name); | |
1321 | } | |
1322 | else | |
1323 | { | |
1324 | if (STRICT_ALIGNMENT) | |
1325 | warning ("packed attribute causes inefficient alignment"); | |
1326 | else | |
1327 | warning ("packed attribute is unnecessary"); | |
1328 | } | |
1329 | } | |
3c12fcc2 | 1330 | } |
9328904c MM |
1331 | } |
1332 | ||
1333 | /* Compute the TYPE_MODE for the TYPE (which is a RECORD_TYPE). */ | |
7306ed3f | 1334 | |
65e14bf5 | 1335 | void |
9328904c MM |
1336 | compute_record_mode (type) |
1337 | tree type; | |
1338 | { | |
770ae6cc RK |
1339 | tree field; |
1340 | enum machine_mode mode = VOIDmode; | |
1341 | ||
9328904c MM |
1342 | /* Most RECORD_TYPEs have BLKmode, so we start off assuming that. |
1343 | However, if possible, we use a mode that fits in a register | |
1344 | instead, in order to allow for better optimization down the | |
1345 | line. */ | |
1346 | TYPE_MODE (type) = BLKmode; | |
9328904c | 1347 | |
770ae6cc RK |
1348 | if (! host_integerp (TYPE_SIZE (type), 1)) |
1349 | return; | |
9328904c | 1350 | |
770ae6cc RK |
1351 | /* A record which has any BLKmode members must itself be |
1352 | BLKmode; it can't go in a register. Unless the member is | |
1353 | BLKmode only because it isn't aligned. */ | |
1354 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) | |
1355 | { | |
1356 | unsigned HOST_WIDE_INT bitpos; | |
9328904c | 1357 | |
770ae6cc RK |
1358 | if (TREE_CODE (field) != FIELD_DECL) |
1359 | continue; | |
9328904c | 1360 | |
770ae6cc RK |
1361 | if (TREE_CODE (TREE_TYPE (field)) == ERROR_MARK |
1362 | || (TYPE_MODE (TREE_TYPE (field)) == BLKmode | |
1363 | && ! TYPE_NO_FORCE_BLK (TREE_TYPE (field))) | |
1364 | || ! host_integerp (bit_position (field), 1) | |
6a9f6727 | 1365 | || DECL_SIZE (field) == 0 |
770ae6cc RK |
1366 | || ! host_integerp (DECL_SIZE (field), 1)) |
1367 | return; | |
1368 | ||
1369 | bitpos = int_bit_position (field); | |
786de7eb | 1370 | |
770ae6cc RK |
1371 | /* Must be BLKmode if any field crosses a word boundary, |
1372 | since extract_bit_field can't handle that in registers. */ | |
1373 | if (bitpos / BITS_PER_WORD | |
382110c0 | 1374 | != ((tree_low_cst (DECL_SIZE (field), 1) + bitpos - 1) |
770ae6cc | 1375 | / BITS_PER_WORD) |
ad26fb41 RK |
1376 | /* But there is no problem if the field is entire words |
1377 | or bigger than a word. */ | |
1378 | && ! (tree_low_cst (DECL_SIZE (field), 1) % BITS_PER_WORD == 0 | |
1379 | || compare_tree_int (DECL_SIZE (field), BITS_PER_WORD) > 0)) | |
770ae6cc RK |
1380 | return; |
1381 | ||
1382 | /* If this field is the whole struct, remember its mode so | |
1383 | that, say, we can put a double in a class into a DF | |
a8ca7756 JW |
1384 | register instead of forcing it to live in the stack. */ |
1385 | if (simple_cst_equal (TYPE_SIZE (type), DECL_SIZE (field))) | |
770ae6cc | 1386 | mode = DECL_MODE (field); |
9328904c | 1387 | |
31a02448 | 1388 | #ifdef MEMBER_TYPE_FORCES_BLK |
770ae6cc RK |
1389 | /* With some targets, eg. c4x, it is sub-optimal |
1390 | to access an aligned BLKmode structure as a scalar. */ | |
0d7839da | 1391 | |
182e515e | 1392 | if (MEMBER_TYPE_FORCES_BLK (field, mode)) |
770ae6cc | 1393 | return; |
31a02448 | 1394 | #endif /* MEMBER_TYPE_FORCES_BLK */ |
770ae6cc | 1395 | } |
9328904c | 1396 | |
a8ca7756 JW |
1397 | /* If we only have one real field; use its mode. This only applies to |
1398 | RECORD_TYPE. This does not apply to unions. */ | |
1399 | if (TREE_CODE (type) == RECORD_TYPE && mode != VOIDmode) | |
770ae6cc RK |
1400 | TYPE_MODE (type) = mode; |
1401 | else | |
1402 | TYPE_MODE (type) = mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1); | |
1403 | ||
1404 | /* If structure's known alignment is less than what the scalar | |
1405 | mode would need, and it matters, then stick with BLKmode. */ | |
1406 | if (TYPE_MODE (type) != BLKmode | |
1407 | && STRICT_ALIGNMENT | |
1408 | && ! (TYPE_ALIGN (type) >= BIGGEST_ALIGNMENT | |
1409 | || TYPE_ALIGN (type) >= GET_MODE_ALIGNMENT (TYPE_MODE (type)))) | |
1410 | { | |
1411 | /* If this is the only reason this type is BLKmode, then | |
1412 | don't force containing types to be BLKmode. */ | |
1413 | TYPE_NO_FORCE_BLK (type) = 1; | |
1414 | TYPE_MODE (type) = BLKmode; | |
9328904c | 1415 | } |
7306ed3f | 1416 | } |
9328904c MM |
1417 | |
1418 | /* Compute TYPE_SIZE and TYPE_ALIGN for TYPE, once it has been laid | |
1419 | out. */ | |
1420 | ||
1421 | static void | |
1422 | finalize_type_size (type) | |
1423 | tree type; | |
1424 | { | |
1425 | /* Normally, use the alignment corresponding to the mode chosen. | |
1426 | However, where strict alignment is not required, avoid | |
1427 | over-aligning structures, since most compilers do not do this | |
1428 | alignment. */ | |
1429 | ||
1430 | if (TYPE_MODE (type) != BLKmode && TYPE_MODE (type) != VOIDmode | |
1431 | && (STRICT_ALIGNMENT | |
1432 | || (TREE_CODE (type) != RECORD_TYPE && TREE_CODE (type) != UNION_TYPE | |
1433 | && TREE_CODE (type) != QUAL_UNION_TYPE | |
1434 | && TREE_CODE (type) != ARRAY_TYPE))) | |
11cf4d18 JJ |
1435 | { |
1436 | TYPE_ALIGN (type) = GET_MODE_ALIGNMENT (TYPE_MODE (type)); | |
1437 | TYPE_USER_ALIGN (type) = 0; | |
1438 | } | |
9328904c MM |
1439 | |
1440 | /* Do machine-dependent extra alignment. */ | |
1441 | #ifdef ROUND_TYPE_ALIGN | |
1442 | TYPE_ALIGN (type) | |
1443 | = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (type), BITS_PER_UNIT); | |
1444 | #endif | |
1445 | ||
9328904c | 1446 | /* If we failed to find a simple way to calculate the unit size |
770ae6cc | 1447 | of the type, find it by division. */ |
9328904c MM |
1448 | if (TYPE_SIZE_UNIT (type) == 0 && TYPE_SIZE (type) != 0) |
1449 | /* TYPE_SIZE (type) is computed in bitsizetype. After the division, the | |
1450 | result will fit in sizetype. We will get more efficient code using | |
1451 | sizetype, so we force a conversion. */ | |
1452 | TYPE_SIZE_UNIT (type) | |
1453 | = convert (sizetype, | |
1454 | size_binop (FLOOR_DIV_EXPR, TYPE_SIZE (type), | |
770ae6cc | 1455 | bitsize_unit_node)); |
9328904c | 1456 | |
770ae6cc RK |
1457 | if (TYPE_SIZE (type) != 0) |
1458 | { | |
770ae6cc RK |
1459 | TYPE_SIZE (type) = round_up (TYPE_SIZE (type), TYPE_ALIGN (type)); |
1460 | TYPE_SIZE_UNIT (type) | |
1461 | = round_up (TYPE_SIZE_UNIT (type), TYPE_ALIGN (type) / BITS_PER_UNIT); | |
770ae6cc RK |
1462 | } |
1463 | ||
1464 | /* Evaluate nonconstant sizes only once, either now or as soon as safe. */ | |
1465 | if (TYPE_SIZE (type) != 0 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) | |
1466 | TYPE_SIZE (type) = variable_size (TYPE_SIZE (type)); | |
9328904c MM |
1467 | if (TYPE_SIZE_UNIT (type) != 0 |
1468 | && TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST) | |
1469 | TYPE_SIZE_UNIT (type) = variable_size (TYPE_SIZE_UNIT (type)); | |
1470 | ||
1471 | /* Also layout any other variants of the type. */ | |
1472 | if (TYPE_NEXT_VARIANT (type) | |
1473 | || type != TYPE_MAIN_VARIANT (type)) | |
1474 | { | |
1475 | tree variant; | |
1476 | /* Record layout info of this variant. */ | |
1477 | tree size = TYPE_SIZE (type); | |
1478 | tree size_unit = TYPE_SIZE_UNIT (type); | |
1479 | unsigned int align = TYPE_ALIGN (type); | |
11cf4d18 | 1480 | unsigned int user_align = TYPE_USER_ALIGN (type); |
9328904c MM |
1481 | enum machine_mode mode = TYPE_MODE (type); |
1482 | ||
1483 | /* Copy it into all variants. */ | |
1484 | for (variant = TYPE_MAIN_VARIANT (type); | |
1485 | variant != 0; | |
1486 | variant = TYPE_NEXT_VARIANT (variant)) | |
1487 | { | |
1488 | TYPE_SIZE (variant) = size; | |
1489 | TYPE_SIZE_UNIT (variant) = size_unit; | |
1490 | TYPE_ALIGN (variant) = align; | |
11cf4d18 | 1491 | TYPE_USER_ALIGN (variant) = user_align; |
9328904c MM |
1492 | TYPE_MODE (variant) = mode; |
1493 | } | |
1494 | } | |
1495 | } | |
1496 | ||
1497 | /* Do all of the work required to layout the type indicated by RLI, | |
1498 | once the fields have been laid out. This function will call `free' | |
17bbb839 MM |
1499 | for RLI, unless FREE_P is false. Passing a value other than false |
1500 | for FREE_P is bad practice; this option only exists to support the | |
1501 | G++ 3.2 ABI. */ | |
9328904c MM |
1502 | |
1503 | void | |
17bbb839 | 1504 | finish_record_layout (rli, free_p) |
9328904c | 1505 | record_layout_info rli; |
17bbb839 | 1506 | int free_p; |
9328904c | 1507 | { |
770ae6cc RK |
1508 | /* Compute the final size. */ |
1509 | finalize_record_size (rli); | |
1510 | ||
1511 | /* Compute the TYPE_MODE for the record. */ | |
1512 | compute_record_mode (rli->t); | |
cc9d4a85 | 1513 | |
8d8238b6 JM |
1514 | /* Perform any last tweaks to the TYPE_SIZE, etc. */ |
1515 | finalize_type_size (rli->t); | |
1516 | ||
9328904c MM |
1517 | /* Lay out any static members. This is done now because their type |
1518 | may use the record's type. */ | |
1519 | while (rli->pending_statics) | |
1520 | { | |
1521 | layout_decl (TREE_VALUE (rli->pending_statics), 0); | |
1522 | rli->pending_statics = TREE_CHAIN (rli->pending_statics); | |
1523 | } | |
cc9d4a85 | 1524 | |
9328904c | 1525 | /* Clean up. */ |
17bbb839 MM |
1526 | if (free_p) |
1527 | free (rli); | |
9328904c | 1528 | } |
7306ed3f | 1529 | \f |
4977bab6 ZW |
1530 | |
1531 | /* Finish processing a builtin RECORD_TYPE type TYPE. It's name is | |
1532 | NAME, its fields are chained in reverse on FIELDS. | |
1533 | ||
1534 | If ALIGN_TYPE is non-null, it is given the same alignment as | |
1535 | ALIGN_TYPE. */ | |
1536 | ||
1537 | void | |
1538 | finish_builtin_struct (type, name, fields, align_type) | |
1539 | tree type; | |
1540 | const char *name; | |
1541 | tree fields; | |
1542 | tree align_type; | |
1543 | { | |
1544 | tree tail, next; | |
1545 | ||
1546 | for (tail = NULL_TREE; fields; tail = fields, fields = next) | |
1547 | { | |
1548 | DECL_FIELD_CONTEXT (fields) = type; | |
1549 | next = TREE_CHAIN (fields); | |
1550 | TREE_CHAIN (fields) = tail; | |
1551 | } | |
1552 | TYPE_FIELDS (type) = tail; | |
1553 | ||
1554 | if (align_type) | |
1555 | { | |
1556 | TYPE_ALIGN (type) = TYPE_ALIGN (align_type); | |
1557 | TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (align_type); | |
1558 | } | |
1559 | ||
1560 | layout_type (type); | |
1561 | #if 0 /* not yet, should get fixed properly later */ | |
1562 | TYPE_NAME (type) = make_type_decl (get_identifier (name), type); | |
1563 | #else | |
1564 | TYPE_NAME (type) = build_decl (TYPE_DECL, get_identifier (name), type); | |
1565 | #endif | |
1566 | TYPE_STUB_DECL (type) = TYPE_NAME (type); | |
1567 | layout_decl (TYPE_NAME (type), 0); | |
1568 | } | |
1569 | ||
7306ed3f JW |
1570 | /* Calculate the mode, size, and alignment for TYPE. |
1571 | For an array type, calculate the element separation as well. | |
1572 | Record TYPE on the chain of permanent or temporary types | |
1573 | so that dbxout will find out about it. | |
1574 | ||
1575 | TYPE_SIZE of a type is nonzero if the type has been laid out already. | |
1576 | layout_type does nothing on such a type. | |
1577 | ||
1578 | If the type is incomplete, its TYPE_SIZE remains zero. */ | |
1579 | ||
1580 | void | |
1581 | layout_type (type) | |
1582 | tree type; | |
1583 | { | |
7306ed3f JW |
1584 | if (type == 0) |
1585 | abort (); | |
1586 | ||
1587 | /* Do nothing if type has been laid out before. */ | |
1588 | if (TYPE_SIZE (type)) | |
1589 | return; | |
1590 | ||
7306ed3f JW |
1591 | switch (TREE_CODE (type)) |
1592 | { | |
1593 | case LANG_TYPE: | |
1594 | /* This kind of type is the responsibility | |
9faa82d8 | 1595 | of the language-specific code. */ |
7306ed3f JW |
1596 | abort (); |
1597 | ||
2d76cb1a | 1598 | case BOOLEAN_TYPE: /* Used for Java, Pascal, and Chill. */ |
e9a25f70 | 1599 | if (TYPE_PRECISION (type) == 0) |
2d76cb1a | 1600 | TYPE_PRECISION (type) = 1; /* default to one byte/boolean. */ |
d4b60170 | 1601 | |
2d76cb1a | 1602 | /* ... fall through ... */ |
e9a25f70 | 1603 | |
7306ed3f JW |
1604 | case INTEGER_TYPE: |
1605 | case ENUMERAL_TYPE: | |
fc69eca0 | 1606 | case CHAR_TYPE: |
e2a77f99 RK |
1607 | if (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST |
1608 | && tree_int_cst_sgn (TYPE_MIN_VALUE (type)) >= 0) | |
7306ed3f JW |
1609 | TREE_UNSIGNED (type) = 1; |
1610 | ||
5e9bec99 RK |
1611 | TYPE_MODE (type) = smallest_mode_for_size (TYPE_PRECISION (type), |
1612 | MODE_INT); | |
06ceef4e | 1613 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1614 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1615 | break; |
1616 | ||
1617 | case REAL_TYPE: | |
1618 | TYPE_MODE (type) = mode_for_size (TYPE_PRECISION (type), MODE_FLOAT, 0); | |
06ceef4e | 1619 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1620 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1621 | break; |
1622 | ||
1623 | case COMPLEX_TYPE: | |
1624 | TREE_UNSIGNED (type) = TREE_UNSIGNED (TREE_TYPE (type)); | |
1625 | TYPE_MODE (type) | |
1626 | = mode_for_size (2 * TYPE_PRECISION (TREE_TYPE (type)), | |
1627 | (TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE | |
1628 | ? MODE_COMPLEX_INT : MODE_COMPLEX_FLOAT), | |
1629 | 0); | |
06ceef4e | 1630 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1631 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1632 | break; |
1633 | ||
0b4565c9 BS |
1634 | case VECTOR_TYPE: |
1635 | { | |
1636 | tree subtype; | |
1637 | ||
1638 | subtype = TREE_TYPE (type); | |
1639 | TREE_UNSIGNED (type) = TREE_UNSIGNED (subtype); | |
1640 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); | |
1641 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); | |
1642 | } | |
1643 | break; | |
1644 | ||
7306ed3f | 1645 | case VOID_TYPE: |
770ae6cc | 1646 | /* This is an incomplete type and so doesn't have a size. */ |
7306ed3f | 1647 | TYPE_ALIGN (type) = 1; |
11cf4d18 | 1648 | TYPE_USER_ALIGN (type) = 0; |
7306ed3f JW |
1649 | TYPE_MODE (type) = VOIDmode; |
1650 | break; | |
1651 | ||
321cb743 | 1652 | case OFFSET_TYPE: |
06ceef4e | 1653 | TYPE_SIZE (type) = bitsize_int (POINTER_SIZE); |
ead17059 | 1654 | TYPE_SIZE_UNIT (type) = size_int (POINTER_SIZE / BITS_PER_UNIT); |
25caaba8 R |
1655 | /* A pointer might be MODE_PARTIAL_INT, |
1656 | but ptrdiff_t must be integral. */ | |
1657 | TYPE_MODE (type) = mode_for_size (POINTER_SIZE, MODE_INT, 0); | |
321cb743 MT |
1658 | break; |
1659 | ||
7306ed3f JW |
1660 | case FUNCTION_TYPE: |
1661 | case METHOD_TYPE: | |
13275056 | 1662 | TYPE_MODE (type) = mode_for_size (2 * POINTER_SIZE, MODE_INT, 0); |
06ceef4e | 1663 | TYPE_SIZE (type) = bitsize_int (2 * POINTER_SIZE); |
ead17059 | 1664 | TYPE_SIZE_UNIT (type) = size_int ((2 * POINTER_SIZE) / BITS_PER_UNIT); |
7306ed3f JW |
1665 | break; |
1666 | ||
1667 | case POINTER_TYPE: | |
1668 | case REFERENCE_TYPE: | |
b5d6a2ff | 1669 | { |
b5d6a2ff | 1670 | |
4977bab6 ZW |
1671 | enum machine_mode mode = ((TREE_CODE (type) == REFERENCE_TYPE |
1672 | && reference_types_internal) | |
1673 | ? Pmode : TYPE_MODE (type)); | |
1674 | ||
1675 | int nbits = GET_MODE_BITSIZE (mode); | |
1676 | ||
b5d6a2ff | 1677 | TYPE_SIZE (type) = bitsize_int (nbits); |
4977bab6 | 1678 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (mode)); |
b5d6a2ff RK |
1679 | TREE_UNSIGNED (type) = 1; |
1680 | TYPE_PRECISION (type) = nbits; | |
1681 | } | |
7306ed3f JW |
1682 | break; |
1683 | ||
1684 | case ARRAY_TYPE: | |
1685 | { | |
b3694847 SS |
1686 | tree index = TYPE_DOMAIN (type); |
1687 | tree element = TREE_TYPE (type); | |
7306ed3f JW |
1688 | |
1689 | build_pointer_type (element); | |
1690 | ||
1691 | /* We need to know both bounds in order to compute the size. */ | |
1692 | if (index && TYPE_MAX_VALUE (index) && TYPE_MIN_VALUE (index) | |
1693 | && TYPE_SIZE (element)) | |
1694 | { | |
e24ff973 RK |
1695 | tree ub = TYPE_MAX_VALUE (index); |
1696 | tree lb = TYPE_MIN_VALUE (index); | |
1697 | tree length; | |
74a4fbfc | 1698 | tree element_size; |
e24ff973 | 1699 | |
a2d53b28 RH |
1700 | /* The initial subtraction should happen in the original type so |
1701 | that (possible) negative values are handled appropriately. */ | |
e24ff973 | 1702 | length = size_binop (PLUS_EXPR, size_one_node, |
fed3cef0 RK |
1703 | convert (sizetype, |
1704 | fold (build (MINUS_EXPR, | |
1705 | TREE_TYPE (lb), | |
1706 | ub, lb)))); | |
7306ed3f | 1707 | |
74a4fbfc DB |
1708 | /* Special handling for arrays of bits (for Chill). */ |
1709 | element_size = TYPE_SIZE (element); | |
382110c0 RK |
1710 | if (TYPE_PACKED (type) && INTEGRAL_TYPE_P (element) |
1711 | && (integer_zerop (TYPE_MAX_VALUE (element)) | |
1712 | || integer_onep (TYPE_MAX_VALUE (element))) | |
1713 | && host_integerp (TYPE_MIN_VALUE (element), 1)) | |
74a4fbfc | 1714 | { |
d4b60170 | 1715 | HOST_WIDE_INT maxvalue |
382110c0 | 1716 | = tree_low_cst (TYPE_MAX_VALUE (element), 1); |
d4b60170 | 1717 | HOST_WIDE_INT minvalue |
382110c0 | 1718 | = tree_low_cst (TYPE_MIN_VALUE (element), 1); |
d4b60170 | 1719 | |
74a4fbfc DB |
1720 | if (maxvalue - minvalue == 1 |
1721 | && (maxvalue == 1 || maxvalue == 0)) | |
1722 | element_size = integer_one_node; | |
1723 | } | |
1724 | ||
0d3c8800 RK |
1725 | /* If neither bound is a constant and sizetype is signed, make |
1726 | sure the size is never negative. We should really do this | |
1727 | if *either* bound is non-constant, but this is the best | |
1728 | compromise between C and Ada. */ | |
1729 | if (! TREE_UNSIGNED (sizetype) | |
1730 | && TREE_CODE (TYPE_MIN_VALUE (index)) != INTEGER_CST | |
1731 | && TREE_CODE (TYPE_MAX_VALUE (index)) != INTEGER_CST) | |
1732 | length = size_binop (MAX_EXPR, length, size_zero_node); | |
1733 | ||
fed3cef0 RK |
1734 | TYPE_SIZE (type) = size_binop (MULT_EXPR, element_size, |
1735 | convert (bitsizetype, length)); | |
ead17059 RH |
1736 | |
1737 | /* If we know the size of the element, calculate the total | |
1738 | size directly, rather than do some division thing below. | |
1739 | This optimization helps Fortran assumed-size arrays | |
1740 | (where the size of the array is determined at runtime) | |
7771032e DB |
1741 | substantially. |
1742 | Note that we can't do this in the case where the size of | |
1743 | the elements is one bit since TYPE_SIZE_UNIT cannot be | |
1744 | set correctly in that case. */ | |
fed3cef0 | 1745 | if (TYPE_SIZE_UNIT (element) != 0 && ! integer_onep (element_size)) |
d4b60170 RK |
1746 | TYPE_SIZE_UNIT (type) |
1747 | = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (element), length); | |
7306ed3f JW |
1748 | } |
1749 | ||
1750 | /* Now round the alignment and size, | |
1751 | using machine-dependent criteria if any. */ | |
1752 | ||
1753 | #ifdef ROUND_TYPE_ALIGN | |
1754 | TYPE_ALIGN (type) | |
1755 | = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (element), BITS_PER_UNIT); | |
1756 | #else | |
1757 | TYPE_ALIGN (type) = MAX (TYPE_ALIGN (element), BITS_PER_UNIT); | |
1758 | #endif | |
c163d21d | 1759 | TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (element); |
7306ed3f JW |
1760 | TYPE_MODE (type) = BLKmode; |
1761 | if (TYPE_SIZE (type) != 0 | |
31a02448 | 1762 | #ifdef MEMBER_TYPE_FORCES_BLK |
182e515e | 1763 | && ! MEMBER_TYPE_FORCES_BLK (type, VOIDmode) |
31a02448 | 1764 | #endif |
7306ed3f JW |
1765 | /* BLKmode elements force BLKmode aggregate; |
1766 | else extract/store fields may lose. */ | |
1767 | && (TYPE_MODE (TREE_TYPE (type)) != BLKmode | |
1768 | || TYPE_NO_FORCE_BLK (TREE_TYPE (type)))) | |
1769 | { | |
a1471322 RK |
1770 | /* One-element arrays get the component type's mode. */ |
1771 | if (simple_cst_equal (TYPE_SIZE (type), | |
1772 | TYPE_SIZE (TREE_TYPE (type)))) | |
1773 | TYPE_MODE (type) = TYPE_MODE (TREE_TYPE (type)); | |
1774 | else | |
1775 | TYPE_MODE (type) | |
1776 | = mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1); | |
7306ed3f | 1777 | |
72c602fc RK |
1778 | if (TYPE_MODE (type) != BLKmode |
1779 | && STRICT_ALIGNMENT && TYPE_ALIGN (type) < BIGGEST_ALIGNMENT | |
1780 | && TYPE_ALIGN (type) < GET_MODE_ALIGNMENT (TYPE_MODE (type)) | |
7306ed3f JW |
1781 | && TYPE_MODE (type) != BLKmode) |
1782 | { | |
1783 | TYPE_NO_FORCE_BLK (type) = 1; | |
1784 | TYPE_MODE (type) = BLKmode; | |
1785 | } | |
7306ed3f JW |
1786 | } |
1787 | break; | |
1788 | } | |
1789 | ||
1790 | case RECORD_TYPE: | |
cc9d4a85 MM |
1791 | case UNION_TYPE: |
1792 | case QUAL_UNION_TYPE: | |
9328904c MM |
1793 | { |
1794 | tree field; | |
1795 | record_layout_info rli; | |
1796 | ||
1797 | /* Initialize the layout information. */ | |
770ae6cc RK |
1798 | rli = start_record_layout (type); |
1799 | ||
cc9d4a85 MM |
1800 | /* If this is a QUAL_UNION_TYPE, we want to process the fields |
1801 | in the reverse order in building the COND_EXPR that denotes | |
1802 | its size. We reverse them again later. */ | |
1803 | if (TREE_CODE (type) == QUAL_UNION_TYPE) | |
1804 | TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type)); | |
770ae6cc RK |
1805 | |
1806 | /* Place all the fields. */ | |
9328904c | 1807 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) |
770ae6cc RK |
1808 | place_field (rli, field); |
1809 | ||
cc9d4a85 MM |
1810 | if (TREE_CODE (type) == QUAL_UNION_TYPE) |
1811 | TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type)); | |
770ae6cc | 1812 | |
e0cea8d9 RK |
1813 | if (lang_adjust_rli) |
1814 | (*lang_adjust_rli) (rli); | |
1815 | ||
9328904c | 1816 | /* Finish laying out the record. */ |
17bbb839 | 1817 | finish_record_layout (rli, /*free_p=*/true); |
9328904c | 1818 | } |
7306ed3f JW |
1819 | break; |
1820 | ||
2d76cb1a | 1821 | case SET_TYPE: /* Used by Chill and Pascal. */ |
b5d11e41 PB |
1822 | if (TREE_CODE (TYPE_MAX_VALUE (TYPE_DOMAIN (type))) != INTEGER_CST |
1823 | || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (type))) != INTEGER_CST) | |
cf403648 | 1824 | abort (); |
b5d11e41 PB |
1825 | else |
1826 | { | |
1827 | #ifndef SET_WORD_SIZE | |
1828 | #define SET_WORD_SIZE BITS_PER_WORD | |
1829 | #endif | |
729a2125 RK |
1830 | unsigned int alignment |
1831 | = set_alignment ? set_alignment : SET_WORD_SIZE; | |
0384674e RK |
1832 | HOST_WIDE_INT size_in_bits |
1833 | = (tree_low_cst (TYPE_MAX_VALUE (TYPE_DOMAIN (type)), 0) | |
1834 | - tree_low_cst (TYPE_MIN_VALUE (TYPE_DOMAIN (type)), 0) + 1); | |
1835 | HOST_WIDE_INT rounded_size | |
b5d11e41 | 1836 | = ((size_in_bits + alignment - 1) / alignment) * alignment; |
729a2125 RK |
1837 | |
1838 | if (rounded_size > (int) alignment) | |
b5d11e41 PB |
1839 | TYPE_MODE (type) = BLKmode; |
1840 | else | |
1841 | TYPE_MODE (type) = mode_for_size (alignment, MODE_INT, 1); | |
729a2125 | 1842 | |
06ceef4e | 1843 | TYPE_SIZE (type) = bitsize_int (rounded_size); |
ead17059 | 1844 | TYPE_SIZE_UNIT (type) = size_int (rounded_size / BITS_PER_UNIT); |
b5d11e41 | 1845 | TYPE_ALIGN (type) = alignment; |
11cf4d18 | 1846 | TYPE_USER_ALIGN (type) = 0; |
b5d11e41 PB |
1847 | TYPE_PRECISION (type) = size_in_bits; |
1848 | } | |
1849 | break; | |
1850 | ||
4cc89e53 RS |
1851 | case FILE_TYPE: |
1852 | /* The size may vary in different languages, so the language front end | |
1853 | should fill in the size. */ | |
1854 | TYPE_ALIGN (type) = BIGGEST_ALIGNMENT; | |
11cf4d18 | 1855 | TYPE_USER_ALIGN (type) = 0; |
4cc89e53 RS |
1856 | TYPE_MODE (type) = BLKmode; |
1857 | break; | |
1858 | ||
7306ed3f JW |
1859 | default: |
1860 | abort (); | |
729a2125 | 1861 | } |
7306ed3f | 1862 | |
9328904c | 1863 | /* Compute the final TYPE_SIZE, TYPE_ALIGN, etc. for TYPE. For |
cc9d4a85 MM |
1864 | records and unions, finish_record_layout already called this |
1865 | function. */ | |
786de7eb | 1866 | if (TREE_CODE (type) != RECORD_TYPE |
cc9d4a85 MM |
1867 | && TREE_CODE (type) != UNION_TYPE |
1868 | && TREE_CODE (type) != QUAL_UNION_TYPE) | |
9328904c | 1869 | finalize_type_size (type); |
7306ed3f | 1870 | |
fed3cef0 RK |
1871 | /* If this type is created before sizetype has been permanently set, |
1872 | record it so set_sizetype can fix it up. */ | |
1873 | if (! sizetype_set) | |
ad41cc2a | 1874 | early_type_list = tree_cons (NULL_TREE, type, early_type_list); |
dc5041ab JJ |
1875 | |
1876 | /* If an alias set has been set for this aggregate when it was incomplete, | |
1877 | force it into alias set 0. | |
1878 | This is too conservative, but we cannot call record_component_aliases | |
1879 | here because some frontends still change the aggregates after | |
1880 | layout_type. */ | |
1881 | if (AGGREGATE_TYPE_P (type) && TYPE_ALIAS_SET_KNOWN_P (type)) | |
1882 | TYPE_ALIAS_SET (type) = 0; | |
7306ed3f JW |
1883 | } |
1884 | \f | |
1885 | /* Create and return a type for signed integers of PRECISION bits. */ | |
1886 | ||
1887 | tree | |
1888 | make_signed_type (precision) | |
1889 | int precision; | |
1890 | { | |
b3694847 | 1891 | tree type = make_node (INTEGER_TYPE); |
7306ed3f JW |
1892 | |
1893 | TYPE_PRECISION (type) = precision; | |
1894 | ||
fed3cef0 | 1895 | fixup_signed_type (type); |
7306ed3f JW |
1896 | return type; |
1897 | } | |
1898 | ||
1899 | /* Create and return a type for unsigned integers of PRECISION bits. */ | |
1900 | ||
1901 | tree | |
1902 | make_unsigned_type (precision) | |
1903 | int precision; | |
1904 | { | |
b3694847 | 1905 | tree type = make_node (INTEGER_TYPE); |
7306ed3f JW |
1906 | |
1907 | TYPE_PRECISION (type) = precision; | |
1908 | ||
7306ed3f JW |
1909 | fixup_unsigned_type (type); |
1910 | return type; | |
1911 | } | |
fed3cef0 RK |
1912 | \f |
1913 | /* Initialize sizetype and bitsizetype to a reasonable and temporary | |
1914 | value to enable integer types to be created. */ | |
1915 | ||
1916 | void | |
1917 | initialize_sizetypes () | |
1918 | { | |
1919 | tree t = make_node (INTEGER_TYPE); | |
1920 | ||
1921 | /* Set this so we do something reasonable for the build_int_2 calls | |
1922 | below. */ | |
1923 | integer_type_node = t; | |
1924 | ||
1925 | TYPE_MODE (t) = SImode; | |
1926 | TYPE_ALIGN (t) = GET_MODE_ALIGNMENT (SImode); | |
11cf4d18 | 1927 | TYPE_USER_ALIGN (t) = 0; |
fed3cef0 RK |
1928 | TYPE_SIZE (t) = build_int_2 (GET_MODE_BITSIZE (SImode), 0); |
1929 | TYPE_SIZE_UNIT (t) = build_int_2 (GET_MODE_SIZE (SImode), 0); | |
1930 | TREE_UNSIGNED (t) = 1; | |
1931 | TYPE_PRECISION (t) = GET_MODE_BITSIZE (SImode); | |
1932 | TYPE_MIN_VALUE (t) = build_int_2 (0, 0); | |
770ae6cc | 1933 | TYPE_IS_SIZETYPE (t) = 1; |
fed3cef0 RK |
1934 | |
1935 | /* 1000 avoids problems with possible overflow and is certainly | |
1936 | larger than any size value we'd want to be storing. */ | |
1937 | TYPE_MAX_VALUE (t) = build_int_2 (1000, 0); | |
1938 | ||
1939 | /* These two must be different nodes because of the caching done in | |
1940 | size_int_wide. */ | |
1941 | sizetype = t; | |
1942 | bitsizetype = copy_node (t); | |
1943 | integer_type_node = 0; | |
1944 | } | |
7306ed3f | 1945 | |
896cced4 | 1946 | /* Set sizetype to TYPE, and initialize *sizetype accordingly. |
f8dac6eb R |
1947 | Also update the type of any standard type's sizes made so far. */ |
1948 | ||
1949 | void | |
1950 | set_sizetype (type) | |
1951 | tree type; | |
1952 | { | |
d4b60170 | 1953 | int oprecision = TYPE_PRECISION (type); |
f8dac6eb | 1954 | /* The *bitsizetype types use a precision that avoids overflows when |
d4b60170 RK |
1955 | calculating signed sizes / offsets in bits. However, when |
1956 | cross-compiling from a 32 bit to a 64 bit host, we are limited to 64 bit | |
1957 | precision. */ | |
11a6092b | 1958 | int precision = MIN (oprecision + BITS_PER_UNIT_LOG + 1, |
d4b60170 | 1959 | 2 * HOST_BITS_PER_WIDE_INT); |
fed3cef0 | 1960 | unsigned int i; |
ad41cc2a | 1961 | tree t; |
fed3cef0 RK |
1962 | |
1963 | if (sizetype_set) | |
1964 | abort (); | |
81b3411c | 1965 | |
fed3cef0 RK |
1966 | /* Make copies of nodes since we'll be setting TYPE_IS_SIZETYPE. */ |
1967 | sizetype = copy_node (type); | |
21318741 | 1968 | TYPE_DOMAIN (sizetype) = type; |
770ae6cc | 1969 | TYPE_IS_SIZETYPE (sizetype) = 1; |
81b3411c BS |
1970 | bitsizetype = make_node (INTEGER_TYPE); |
1971 | TYPE_NAME (bitsizetype) = TYPE_NAME (type); | |
f8dac6eb | 1972 | TYPE_PRECISION (bitsizetype) = precision; |
770ae6cc | 1973 | TYPE_IS_SIZETYPE (bitsizetype) = 1; |
d4b60170 | 1974 | |
896cced4 RH |
1975 | if (TREE_UNSIGNED (type)) |
1976 | fixup_unsigned_type (bitsizetype); | |
1977 | else | |
1978 | fixup_signed_type (bitsizetype); | |
d4b60170 | 1979 | |
f8dac6eb R |
1980 | layout_type (bitsizetype); |
1981 | ||
896cced4 RH |
1982 | if (TREE_UNSIGNED (type)) |
1983 | { | |
1984 | usizetype = sizetype; | |
1985 | ubitsizetype = bitsizetype; | |
fed3cef0 RK |
1986 | ssizetype = copy_node (make_signed_type (oprecision)); |
1987 | sbitsizetype = copy_node (make_signed_type (precision)); | |
896cced4 RH |
1988 | } |
1989 | else | |
1990 | { | |
1991 | ssizetype = sizetype; | |
1992 | sbitsizetype = bitsizetype; | |
fed3cef0 RK |
1993 | usizetype = copy_node (make_unsigned_type (oprecision)); |
1994 | ubitsizetype = copy_node (make_unsigned_type (precision)); | |
896cced4 | 1995 | } |
fed3cef0 RK |
1996 | |
1997 | TYPE_NAME (bitsizetype) = get_identifier ("bit_size_type"); | |
1998 | ||
21318741 | 1999 | /* Show is a sizetype, is a main type, and has no pointers to it. */ |
b6a1cbae | 2000 | for (i = 0; i < ARRAY_SIZE (sizetype_tab); i++) |
21318741 RK |
2001 | { |
2002 | TYPE_IS_SIZETYPE (sizetype_tab[i]) = 1; | |
2003 | TYPE_MAIN_VARIANT (sizetype_tab[i]) = sizetype_tab[i]; | |
2004 | TYPE_NEXT_VARIANT (sizetype_tab[i]) = 0; | |
2005 | TYPE_POINTER_TO (sizetype_tab[i]) = 0; | |
2006 | TYPE_REFERENCE_TO (sizetype_tab[i]) = 0; | |
2007 | } | |
d7db6646 | 2008 | |
fed3cef0 RK |
2009 | /* Go down each of the types we already made and set the proper type |
2010 | for the sizes in them. */ | |
ad41cc2a | 2011 | for (t = early_type_list; t != 0; t = TREE_CHAIN (t)) |
fed3cef0 | 2012 | { |
ad41cc2a | 2013 | if (TREE_CODE (TREE_VALUE (t)) != INTEGER_TYPE) |
fed3cef0 RK |
2014 | abort (); |
2015 | ||
ad41cc2a RK |
2016 | TREE_TYPE (TYPE_SIZE (TREE_VALUE (t))) = bitsizetype; |
2017 | TREE_TYPE (TYPE_SIZE_UNIT (TREE_VALUE (t))) = sizetype; | |
fed3cef0 RK |
2018 | } |
2019 | ||
2020 | early_type_list = 0; | |
2021 | sizetype_set = 1; | |
2022 | } | |
2023 | \f | |
4cc89e53 | 2024 | /* Set the extreme values of TYPE based on its precision in bits, |
13756074 | 2025 | then lay it out. Used when make_signed_type won't do |
4cc89e53 RS |
2026 | because the tree code is not INTEGER_TYPE. |
2027 | E.g. for Pascal, when the -fsigned-char option is given. */ | |
2028 | ||
2029 | void | |
2030 | fixup_signed_type (type) | |
2031 | tree type; | |
2032 | { | |
b3694847 | 2033 | int precision = TYPE_PRECISION (type); |
4cc89e53 | 2034 | |
9cd56be1 JH |
2035 | /* We can not represent properly constants greater then |
2036 | 2 * HOST_BITS_PER_WIDE_INT, still we need the types | |
2037 | as they are used by i386 vector extensions and friends. */ | |
2038 | if (precision > HOST_BITS_PER_WIDE_INT * 2) | |
2039 | precision = HOST_BITS_PER_WIDE_INT * 2; | |
2040 | ||
4cc89e53 | 2041 | TYPE_MIN_VALUE (type) |
13756074 JW |
2042 | = build_int_2 ((precision - HOST_BITS_PER_WIDE_INT > 0 |
2043 | ? 0 : (HOST_WIDE_INT) (-1) << (precision - 1)), | |
2044 | (((HOST_WIDE_INT) (-1) | |
2045 | << (precision - HOST_BITS_PER_WIDE_INT - 1 > 0 | |
2046 | ? precision - HOST_BITS_PER_WIDE_INT - 1 | |
2047 | : 0)))); | |
4cc89e53 | 2048 | TYPE_MAX_VALUE (type) |
13756074 JW |
2049 | = build_int_2 ((precision - HOST_BITS_PER_WIDE_INT > 0 |
2050 | ? -1 : ((HOST_WIDE_INT) 1 << (precision - 1)) - 1), | |
2051 | (precision - HOST_BITS_PER_WIDE_INT - 1 > 0 | |
2052 | ? (((HOST_WIDE_INT) 1 | |
2053 | << (precision - HOST_BITS_PER_WIDE_INT - 1))) - 1 | |
4cc89e53 RS |
2054 | : 0)); |
2055 | ||
2056 | TREE_TYPE (TYPE_MIN_VALUE (type)) = type; | |
2057 | TREE_TYPE (TYPE_MAX_VALUE (type)) = type; | |
2058 | ||
2059 | /* Lay out the type: set its alignment, size, etc. */ | |
4cc89e53 RS |
2060 | layout_type (type); |
2061 | } | |
2062 | ||
7306ed3f | 2063 | /* Set the extreme values of TYPE based on its precision in bits, |
13756074 | 2064 | then lay it out. This is used both in `make_unsigned_type' |
7306ed3f JW |
2065 | and for enumeral types. */ |
2066 | ||
2067 | void | |
2068 | fixup_unsigned_type (type) | |
2069 | tree type; | |
2070 | { | |
b3694847 | 2071 | int precision = TYPE_PRECISION (type); |
7306ed3f | 2072 | |
9cd56be1 JH |
2073 | /* We can not represent properly constants greater then |
2074 | 2 * HOST_BITS_PER_WIDE_INT, still we need the types | |
2075 | as they are used by i386 vector extensions and friends. */ | |
2076 | if (precision > HOST_BITS_PER_WIDE_INT * 2) | |
2077 | precision = HOST_BITS_PER_WIDE_INT * 2; | |
2078 | ||
7306ed3f JW |
2079 | TYPE_MIN_VALUE (type) = build_int_2 (0, 0); |
2080 | TYPE_MAX_VALUE (type) | |
c166a311 | 2081 | = build_int_2 (precision - HOST_BITS_PER_WIDE_INT >= 0 |
13756074 | 2082 | ? -1 : ((HOST_WIDE_INT) 1 << precision) - 1, |
c166a311 CH |
2083 | precision - HOST_BITS_PER_WIDE_INT > 0 |
2084 | ? ((unsigned HOST_WIDE_INT) ~0 | |
2085 | >> (HOST_BITS_PER_WIDE_INT | |
2086 | - (precision - HOST_BITS_PER_WIDE_INT))) | |
7306ed3f JW |
2087 | : 0); |
2088 | TREE_TYPE (TYPE_MIN_VALUE (type)) = type; | |
2089 | TREE_TYPE (TYPE_MAX_VALUE (type)) = type; | |
2090 | ||
2091 | /* Lay out the type: set its alignment, size, etc. */ | |
7306ed3f JW |
2092 | layout_type (type); |
2093 | } | |
2094 | \f | |
2095 | /* Find the best machine mode to use when referencing a bit field of length | |
2096 | BITSIZE bits starting at BITPOS. | |
2097 | ||
2098 | The underlying object is known to be aligned to a boundary of ALIGN bits. | |
2099 | If LARGEST_MODE is not VOIDmode, it means that we should not use a mode | |
2100 | larger than LARGEST_MODE (usually SImode). | |
2101 | ||
2102 | If no mode meets all these conditions, we return VOIDmode. Otherwise, if | |
2103 | VOLATILEP is true or SLOW_BYTE_ACCESS is false, we return the smallest | |
2104 | mode meeting these conditions. | |
2105 | ||
77fa0940 RK |
2106 | Otherwise (VOLATILEP is false and SLOW_BYTE_ACCESS is true), we return |
2107 | the largest mode (but a mode no wider than UNITS_PER_WORD) that meets | |
2108 | all the conditions. */ | |
7306ed3f JW |
2109 | |
2110 | enum machine_mode | |
2111 | get_best_mode (bitsize, bitpos, align, largest_mode, volatilep) | |
2112 | int bitsize, bitpos; | |
729a2125 | 2113 | unsigned int align; |
7306ed3f JW |
2114 | enum machine_mode largest_mode; |
2115 | int volatilep; | |
2116 | { | |
2117 | enum machine_mode mode; | |
770ae6cc | 2118 | unsigned int unit = 0; |
7306ed3f JW |
2119 | |
2120 | /* Find the narrowest integer mode that contains the bit field. */ | |
2121 | for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode; | |
2122 | mode = GET_MODE_WIDER_MODE (mode)) | |
2123 | { | |
2124 | unit = GET_MODE_BITSIZE (mode); | |
956d6950 | 2125 | if ((bitpos % unit) + bitsize <= unit) |
7306ed3f JW |
2126 | break; |
2127 | } | |
2128 | ||
0c61f541 | 2129 | if (mode == VOIDmode |
7306ed3f | 2130 | /* It is tempting to omit the following line |
4e4b555d | 2131 | if STRICT_ALIGNMENT is true. |
7306ed3f JW |
2132 | But that is incorrect, since if the bitfield uses part of 3 bytes |
2133 | and we use a 4-byte mode, we could get a spurious segv | |
2134 | if the extra 4th byte is past the end of memory. | |
2135 | (Though at least one Unix compiler ignores this problem: | |
2136 | that on the Sequent 386 machine. */ | |
770ae6cc | 2137 | || MIN (unit, BIGGEST_ALIGNMENT) > align |
7306ed3f JW |
2138 | || (largest_mode != VOIDmode && unit > GET_MODE_BITSIZE (largest_mode))) |
2139 | return VOIDmode; | |
2140 | ||
77fa0940 RK |
2141 | if (SLOW_BYTE_ACCESS && ! volatilep) |
2142 | { | |
2143 | enum machine_mode wide_mode = VOIDmode, tmode; | |
2144 | ||
2145 | for (tmode = GET_CLASS_NARROWEST_MODE (MODE_INT); tmode != VOIDmode; | |
2146 | tmode = GET_MODE_WIDER_MODE (tmode)) | |
2147 | { | |
2148 | unit = GET_MODE_BITSIZE (tmode); | |
2149 | if (bitpos / unit == (bitpos + bitsize - 1) / unit | |
2150 | && unit <= BITS_PER_WORD | |
770ae6cc | 2151 | && unit <= MIN (align, BIGGEST_ALIGNMENT) |
77fa0940 RK |
2152 | && (largest_mode == VOIDmode |
2153 | || unit <= GET_MODE_BITSIZE (largest_mode))) | |
2154 | wide_mode = tmode; | |
2155 | } | |
2156 | ||
2157 | if (wide_mode != VOIDmode) | |
2158 | return wide_mode; | |
2159 | } | |
7306ed3f JW |
2160 | |
2161 | return mode; | |
2162 | } | |
d7db6646 | 2163 | |
e2500fed | 2164 | #include "gt-stor-layout.h" |