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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 | ||
46c5ad27 AJ |
62 | static void finalize_record_size (record_layout_info); |
63 | static void finalize_type_size (tree); | |
64 | static void place_union_field (record_layout_info, tree); | |
b8089d8d | 65 | #if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED) |
46c5ad27 AJ |
66 | static int excess_unit_span (HOST_WIDE_INT, HOST_WIDE_INT, HOST_WIDE_INT, |
67 | HOST_WIDE_INT, tree); | |
b8089d8d | 68 | #endif |
46c5ad27 AJ |
69 | static unsigned int update_alignment_for_field (record_layout_info, tree, |
70 | unsigned int); | |
71 | extern void debug_rli (record_layout_info); | |
7306ed3f JW |
72 | \f |
73 | /* SAVE_EXPRs for sizes of types and decls, waiting to be expanded. */ | |
74 | ||
e2500fed | 75 | static GTY(()) tree pending_sizes; |
7306ed3f JW |
76 | |
77 | /* Nonzero means cannot safely call expand_expr now, | |
78 | so put variable sizes onto `pending_sizes' instead. */ | |
79 | ||
80 | int immediate_size_expand; | |
81 | ||
b5d6a2ff RK |
82 | /* Show that REFERENCE_TYPES are internal and should be Pmode. Called only |
83 | by front end. */ | |
84 | ||
85 | void | |
46c5ad27 | 86 | internal_reference_types (void) |
b5d6a2ff RK |
87 | { |
88 | reference_types_internal = 1; | |
89 | } | |
90 | ||
770ae6cc RK |
91 | /* Get a list of all the objects put on the pending sizes list. */ |
92 | ||
7306ed3f | 93 | tree |
46c5ad27 | 94 | get_pending_sizes (void) |
7306ed3f JW |
95 | { |
96 | tree chain = pending_sizes; | |
4e4b555d RS |
97 | tree t; |
98 | ||
99 | /* Put each SAVE_EXPR into the current function. */ | |
100 | for (t = chain; t; t = TREE_CHAIN (t)) | |
101 | SAVE_EXPR_CONTEXT (TREE_VALUE (t)) = current_function_decl; | |
d4b60170 | 102 | |
7306ed3f JW |
103 | pending_sizes = 0; |
104 | return chain; | |
105 | } | |
106 | ||
0e9e1e0a | 107 | /* Return nonzero if EXPR is present on the pending sizes list. */ |
fe375cf1 JJ |
108 | |
109 | int | |
46c5ad27 | 110 | is_pending_size (tree expr) |
fe375cf1 JJ |
111 | { |
112 | tree t; | |
113 | ||
114 | for (t = pending_sizes; t; t = TREE_CHAIN (t)) | |
115 | if (TREE_VALUE (t) == expr) | |
116 | return 1; | |
117 | return 0; | |
118 | } | |
119 | ||
120 | /* Add EXPR to the pending sizes list. */ | |
121 | ||
122 | void | |
46c5ad27 | 123 | put_pending_size (tree expr) |
fe375cf1 | 124 | { |
3874585e RK |
125 | /* Strip any simple arithmetic from EXPR to see if it has an underlying |
126 | SAVE_EXPR. */ | |
a9ecacf6 | 127 | expr = skip_simple_arithmetic (expr); |
3874585e RK |
128 | |
129 | if (TREE_CODE (expr) == SAVE_EXPR) | |
130 | pending_sizes = tree_cons (NULL_TREE, expr, pending_sizes); | |
fe375cf1 JJ |
131 | } |
132 | ||
770ae6cc RK |
133 | /* Put a chain of objects into the pending sizes list, which must be |
134 | empty. */ | |
135 | ||
1fd7c4ac | 136 | void |
46c5ad27 | 137 | put_pending_sizes (tree chain) |
1fd7c4ac RK |
138 | { |
139 | if (pending_sizes) | |
140 | abort (); | |
141 | ||
142 | pending_sizes = chain; | |
143 | } | |
144 | ||
76ffb3a0 | 145 | /* Given a size SIZE that may not be a constant, return a SAVE_EXPR |
7306ed3f JW |
146 | to serve as the actual size-expression for a type or decl. */ |
147 | ||
4e4b555d | 148 | tree |
46c5ad27 | 149 | variable_size (tree size) |
7306ed3f | 150 | { |
3695c25f JM |
151 | tree save; |
152 | ||
5e9bec99 RK |
153 | /* If the language-processor is to take responsibility for variable-sized |
154 | items (e.g., languages which have elaboration procedures like Ada), | |
ac79cd5a RK |
155 | just return SIZE unchanged. Likewise for self-referential sizes and |
156 | constant sizes. */ | |
76ffb3a0 | 157 | if (TREE_CONSTANT (size) |
43577e6b | 158 | || (*lang_hooks.decls.global_bindings_p) () < 0 |
679035f3 | 159 | || CONTAINS_PLACEHOLDER_P (size)) |
5e9bec99 RK |
160 | return size; |
161 | ||
3695c25f JM |
162 | if (TREE_CODE (size) == MINUS_EXPR && integer_onep (TREE_OPERAND (size, 1))) |
163 | /* If this is the upper bound of a C array, leave the minus 1 outside | |
164 | the SAVE_EXPR so it can be folded away. */ | |
165 | TREE_OPERAND (size, 0) = save = save_expr (TREE_OPERAND (size, 0)); | |
166 | else | |
167 | size = save = save_expr (size); | |
68de3831 | 168 | |
d26f8097 MM |
169 | /* If an array with a variable number of elements is declared, and |
170 | the elements require destruction, we will emit a cleanup for the | |
171 | array. That cleanup is run both on normal exit from the block | |
172 | and in the exception-handler for the block. Normally, when code | |
173 | is used in both ordinary code and in an exception handler it is | |
174 | `unsaved', i.e., all SAVE_EXPRs are recalculated. However, we do | |
175 | not wish to do that here; the array-size is the same in both | |
176 | places. */ | |
3695c25f JM |
177 | if (TREE_CODE (save) == SAVE_EXPR) |
178 | SAVE_EXPR_PERSISTENT_P (save) = 1; | |
d26f8097 | 179 | |
43577e6b | 180 | if ((*lang_hooks.decls.global_bindings_p) ()) |
7306ed3f | 181 | { |
80f9c711 RS |
182 | if (TREE_CONSTANT (size)) |
183 | error ("type size can't be explicitly evaluated"); | |
184 | else | |
185 | error ("variable-size type declared outside of any function"); | |
186 | ||
fed3cef0 | 187 | return size_one_node; |
7306ed3f JW |
188 | } |
189 | ||
190 | if (immediate_size_expand) | |
3695c25f | 191 | expand_expr (save, const0_rtx, VOIDmode, 0); |
770ae6cc | 192 | else if (cfun != 0 && cfun->x_dont_save_pending_sizes_p) |
d43163b7 MM |
193 | /* The front-end doesn't want us to keep a list of the expressions |
194 | that determine sizes for variable size objects. */ | |
195 | ; | |
fe375cf1 | 196 | else |
3695c25f | 197 | put_pending_size (save); |
7306ed3f JW |
198 | |
199 | return size; | |
200 | } | |
201 | \f | |
202 | #ifndef MAX_FIXED_MODE_SIZE | |
203 | #define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (DImode) | |
204 | #endif | |
205 | ||
206 | /* Return the machine mode to use for a nonscalar of SIZE bits. | |
207 | The mode must be in class CLASS, and have exactly that many bits. | |
208 | If LIMIT is nonzero, modes of wider than MAX_FIXED_MODE_SIZE will not | |
209 | be used. */ | |
210 | ||
211 | enum machine_mode | |
46c5ad27 | 212 | mode_for_size (unsigned int size, enum mode_class class, int limit) |
7306ed3f | 213 | { |
b3694847 | 214 | enum machine_mode mode; |
7306ed3f | 215 | |
72c602fc | 216 | if (limit && size > MAX_FIXED_MODE_SIZE) |
7306ed3f JW |
217 | return BLKmode; |
218 | ||
5e9bec99 | 219 | /* Get the first mode which has this size, in the specified class. */ |
7306ed3f JW |
220 | for (mode = GET_CLASS_NARROWEST_MODE (class); mode != VOIDmode; |
221 | mode = GET_MODE_WIDER_MODE (mode)) | |
72c602fc | 222 | if (GET_MODE_BITSIZE (mode) == size) |
7306ed3f JW |
223 | return mode; |
224 | ||
225 | return BLKmode; | |
226 | } | |
227 | ||
72c602fc RK |
228 | /* Similar, except passed a tree node. */ |
229 | ||
230 | enum machine_mode | |
46c5ad27 | 231 | mode_for_size_tree (tree size, enum mode_class class, int limit) |
72c602fc RK |
232 | { |
233 | if (TREE_CODE (size) != INTEGER_CST | |
5826955d | 234 | || TREE_OVERFLOW (size) |
72c602fc RK |
235 | /* What we really want to say here is that the size can fit in a |
236 | host integer, but we know there's no way we'd find a mode for | |
237 | this many bits, so there's no point in doing the precise test. */ | |
05bccae2 | 238 | || compare_tree_int (size, 1000) > 0) |
72c602fc RK |
239 | return BLKmode; |
240 | else | |
0384674e | 241 | return mode_for_size (tree_low_cst (size, 1), class, limit); |
72c602fc RK |
242 | } |
243 | ||
5e9bec99 RK |
244 | /* Similar, but never return BLKmode; return the narrowest mode that |
245 | contains at least the requested number of bits. */ | |
246 | ||
27922c13 | 247 | enum machine_mode |
46c5ad27 | 248 | smallest_mode_for_size (unsigned int size, enum mode_class class) |
5e9bec99 | 249 | { |
b3694847 | 250 | enum machine_mode mode; |
5e9bec99 RK |
251 | |
252 | /* Get the first mode which has at least this size, in the | |
253 | specified class. */ | |
254 | for (mode = GET_CLASS_NARROWEST_MODE (class); mode != VOIDmode; | |
255 | mode = GET_MODE_WIDER_MODE (mode)) | |
72c602fc | 256 | if (GET_MODE_BITSIZE (mode) >= size) |
5e9bec99 RK |
257 | return mode; |
258 | ||
259 | abort (); | |
260 | } | |
261 | ||
d006aa54 RH |
262 | /* Find an integer mode of the exact same size, or BLKmode on failure. */ |
263 | ||
264 | enum machine_mode | |
46c5ad27 | 265 | int_mode_for_mode (enum machine_mode mode) |
d006aa54 RH |
266 | { |
267 | switch (GET_MODE_CLASS (mode)) | |
268 | { | |
269 | case MODE_INT: | |
270 | case MODE_PARTIAL_INT: | |
271 | break; | |
272 | ||
273 | case MODE_COMPLEX_INT: | |
274 | case MODE_COMPLEX_FLOAT: | |
275 | case MODE_FLOAT: | |
62c07905 JM |
276 | case MODE_VECTOR_INT: |
277 | case MODE_VECTOR_FLOAT: | |
d006aa54 RH |
278 | mode = mode_for_size (GET_MODE_BITSIZE (mode), MODE_INT, 0); |
279 | break; | |
280 | ||
281 | case MODE_RANDOM: | |
282 | if (mode == BLKmode) | |
786de7eb | 283 | break; |
d4b60170 | 284 | |
2d76cb1a | 285 | /* ... fall through ... */ |
d006aa54 RH |
286 | |
287 | case MODE_CC: | |
288 | default: | |
05bccae2 | 289 | abort (); |
d006aa54 RH |
290 | } |
291 | ||
292 | return mode; | |
293 | } | |
294 | ||
187515f5 AO |
295 | /* Return the alignment of MODE. This will be bounded by 1 and |
296 | BIGGEST_ALIGNMENT. */ | |
297 | ||
298 | unsigned int | |
46c5ad27 | 299 | get_mode_alignment (enum machine_mode mode) |
187515f5 AO |
300 | { |
301 | unsigned int alignment; | |
302 | ||
303 | if (GET_MODE_CLASS (mode) == MODE_COMPLEX_FLOAT | |
304 | || GET_MODE_CLASS (mode) == MODE_COMPLEX_INT) | |
305 | alignment = GET_MODE_UNIT_SIZE (mode); | |
306 | else | |
307 | alignment = GET_MODE_SIZE (mode); | |
308 | ||
309 | /* Extract the LSB of the size. */ | |
310 | alignment = alignment & -alignment; | |
311 | alignment *= BITS_PER_UNIT; | |
312 | ||
313 | alignment = MIN (BIGGEST_ALIGNMENT, MAX (1, alignment)); | |
314 | return alignment; | |
315 | } | |
316 | ||
fed3cef0 RK |
317 | /* Return the value of VALUE, rounded up to a multiple of DIVISOR. |
318 | This can only be applied to objects of a sizetype. */ | |
7306ed3f JW |
319 | |
320 | tree | |
46c5ad27 | 321 | round_up (tree value, int divisor) |
7306ed3f | 322 | { |
fed3cef0 RK |
323 | tree arg = size_int_type (divisor, TREE_TYPE (value)); |
324 | ||
325 | return size_binop (MULT_EXPR, size_binop (CEIL_DIV_EXPR, value, arg), arg); | |
326 | } | |
327 | ||
328 | /* Likewise, but round down. */ | |
329 | ||
330 | tree | |
46c5ad27 | 331 | round_down (tree value, int divisor) |
fed3cef0 RK |
332 | { |
333 | tree arg = size_int_type (divisor, TREE_TYPE (value)); | |
334 | ||
335 | return size_binop (MULT_EXPR, size_binop (FLOOR_DIV_EXPR, value, arg), arg); | |
7306ed3f JW |
336 | } |
337 | \f | |
78d55cc8 JM |
338 | /* Subroutine of layout_decl: Force alignment required for the data type. |
339 | But if the decl itself wants greater alignment, don't override that. */ | |
340 | ||
341 | static inline void | |
342 | do_type_align (tree type, tree decl) | |
343 | { | |
344 | if (TYPE_ALIGN (type) > DECL_ALIGN (decl)) | |
345 | { | |
346 | DECL_ALIGN (decl) = TYPE_ALIGN (type); | |
3acef2ae JM |
347 | if (TREE_CODE (decl) == FIELD_DECL) |
348 | DECL_USER_ALIGN (decl) = TYPE_USER_ALIGN (type); | |
78d55cc8 JM |
349 | } |
350 | } | |
351 | ||
7306ed3f JW |
352 | /* Set the size, mode and alignment of a ..._DECL node. |
353 | TYPE_DECL does need this for C++. | |
354 | Note that LABEL_DECL and CONST_DECL nodes do not need this, | |
355 | and FUNCTION_DECL nodes have them set up in a special (and simple) way. | |
356 | Don't call layout_decl for them. | |
357 | ||
358 | KNOWN_ALIGN is the amount of alignment we can assume this | |
359 | decl has with no special effort. It is relevant only for FIELD_DECLs | |
360 | and depends on the previous fields. | |
361 | All that matters about KNOWN_ALIGN is which powers of 2 divide it. | |
362 | If KNOWN_ALIGN is 0, it means, "as much alignment as you like": | |
363 | the record will be aligned to suit. */ | |
364 | ||
365 | void | |
46c5ad27 | 366 | layout_decl (tree decl, unsigned int known_align) |
7306ed3f | 367 | { |
b3694847 SS |
368 | tree type = TREE_TYPE (decl); |
369 | enum tree_code code = TREE_CODE (decl); | |
a46666a9 | 370 | rtx rtl = NULL_RTX; |
7306ed3f JW |
371 | |
372 | if (code == CONST_DECL) | |
373 | return; | |
9df2c88c | 374 | else if (code != VAR_DECL && code != PARM_DECL && code != RESULT_DECL |
33433751 | 375 | && code != TYPE_DECL && code != FIELD_DECL) |
7306ed3f JW |
376 | abort (); |
377 | ||
a46666a9 RH |
378 | rtl = DECL_RTL_IF_SET (decl); |
379 | ||
7306ed3f | 380 | if (type == error_mark_node) |
33433751 | 381 | type = void_type_node; |
7306ed3f | 382 | |
770ae6cc RK |
383 | /* Usually the size and mode come from the data type without change, |
384 | however, the front-end may set the explicit width of the field, so its | |
385 | size may not be the same as the size of its type. This happens with | |
386 | bitfields, of course (an `int' bitfield may be only 2 bits, say), but it | |
387 | also happens with other fields. For example, the C++ front-end creates | |
388 | zero-sized fields corresponding to empty base classes, and depends on | |
389 | layout_type setting DECL_FIELD_BITPOS correctly for the field. Set the | |
4b6bf620 RK |
390 | size in bytes from the size in bits. If we have already set the mode, |
391 | don't set it again since we can be called twice for FIELD_DECLs. */ | |
770ae6cc | 392 | |
7306ed3f | 393 | TREE_UNSIGNED (decl) = TREE_UNSIGNED (type); |
4b6bf620 RK |
394 | if (DECL_MODE (decl) == VOIDmode) |
395 | DECL_MODE (decl) = TYPE_MODE (type); | |
770ae6cc | 396 | |
5e9bec99 | 397 | if (DECL_SIZE (decl) == 0) |
06ceef4e RK |
398 | { |
399 | DECL_SIZE (decl) = TYPE_SIZE (type); | |
400 | DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (type); | |
401 | } | |
1a96dc46 | 402 | else if (DECL_SIZE_UNIT (decl) == 0) |
770ae6cc RK |
403 | DECL_SIZE_UNIT (decl) |
404 | = convert (sizetype, size_binop (CEIL_DIV_EXPR, DECL_SIZE (decl), | |
405 | bitsize_unit_node)); | |
06ceef4e | 406 | |
78d55cc8 JM |
407 | if (code != FIELD_DECL) |
408 | /* For non-fields, update the alignment from the type. */ | |
409 | do_type_align (type, decl); | |
410 | else | |
411 | /* For fields, it's a bit more complicated... */ | |
786de7eb | 412 | { |
78d55cc8 JM |
413 | if (DECL_BIT_FIELD (decl)) |
414 | { | |
415 | DECL_BIT_FIELD_TYPE (decl) = type; | |
7306ed3f | 416 | |
78d55cc8 JM |
417 | /* A zero-length bit-field affects the alignment of the next |
418 | field. */ | |
419 | if (integer_zerop (DECL_SIZE (decl)) | |
420 | && ! DECL_PACKED (decl) | |
421 | && ! (*targetm.ms_bitfield_layout_p) (DECL_FIELD_CONTEXT (decl))) | |
422 | { | |
423 | #ifdef PCC_BITFIELD_TYPE_MATTERS | |
424 | if (PCC_BITFIELD_TYPE_MATTERS) | |
425 | do_type_align (type, decl); | |
426 | else | |
427 | #endif | |
ad3f5759 | 428 | { |
78d55cc8 | 429 | #ifdef EMPTY_FIELD_BOUNDARY |
ad3f5759 AS |
430 | if (EMPTY_FIELD_BOUNDARY > DECL_ALIGN (decl)) |
431 | { | |
432 | DECL_ALIGN (decl) = EMPTY_FIELD_BOUNDARY; | |
433 | DECL_USER_ALIGN (decl) = 0; | |
434 | } | |
78d55cc8 | 435 | #endif |
ad3f5759 | 436 | } |
78d55cc8 JM |
437 | } |
438 | ||
439 | /* See if we can use an ordinary integer mode for a bit-field. | |
440 | Conditions are: a fixed size that is correct for another mode | |
441 | and occupying a complete byte or bytes on proper boundary. */ | |
442 | if (TYPE_SIZE (type) != 0 | |
443 | && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST | |
444 | && GET_MODE_CLASS (TYPE_MODE (type)) == MODE_INT) | |
445 | { | |
446 | enum machine_mode xmode | |
447 | = mode_for_size_tree (DECL_SIZE (decl), MODE_INT, 1); | |
448 | ||
449 | if (xmode != BLKmode && known_align >= GET_MODE_ALIGNMENT (xmode)) | |
450 | { | |
451 | DECL_ALIGN (decl) = MAX (GET_MODE_ALIGNMENT (xmode), | |
452 | DECL_ALIGN (decl)); | |
453 | DECL_MODE (decl) = xmode; | |
454 | DECL_BIT_FIELD (decl) = 0; | |
455 | } | |
456 | } | |
457 | ||
458 | /* Turn off DECL_BIT_FIELD if we won't need it set. */ | |
459 | if (TYPE_MODE (type) == BLKmode && DECL_MODE (decl) == BLKmode | |
460 | && known_align >= TYPE_ALIGN (type) | |
461 | && DECL_ALIGN (decl) >= TYPE_ALIGN (type)) | |
462 | DECL_BIT_FIELD (decl) = 0; | |
463 | } | |
464 | else if (DECL_PACKED (decl) && DECL_USER_ALIGN (decl)) | |
465 | /* Don't touch DECL_ALIGN. For other packed fields, go ahead and | |
466 | round up; we'll reduce it again below. */; | |
467 | else | |
468 | do_type_align (type, decl); | |
6790d1bd RK |
469 | |
470 | /* If the field is of variable size, we can't misalign it since we | |
471 | have no way to make a temporary to align the result. But this | |
472 | isn't an issue if the decl is not addressable. Likewise if it | |
473 | is of unknown size. */ | |
78d55cc8 JM |
474 | if (DECL_PACKED (decl) |
475 | && !DECL_USER_ALIGN (decl) | |
476 | && (DECL_NONADDRESSABLE_P (decl) | |
477 | || DECL_SIZE_UNIT (decl) == 0 | |
478 | || TREE_CODE (DECL_SIZE_UNIT (decl)) == INTEGER_CST)) | |
479 | DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), BITS_PER_UNIT); | |
480 | ||
481 | /* Should this be controlled by DECL_USER_ALIGN, too? */ | |
482 | if (maximum_field_alignment != 0) | |
483 | DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), maximum_field_alignment); | |
484 | if (! DECL_USER_ALIGN (decl)) | |
7306ed3f | 485 | { |
78d55cc8 JM |
486 | /* Some targets (i.e. i386, VMS) limit struct field alignment |
487 | to a lower boundary than alignment of variables unless | |
488 | it was overridden by attribute aligned. */ | |
489 | #ifdef BIGGEST_FIELD_ALIGNMENT | |
490 | DECL_ALIGN (decl) | |
491 | = MIN (DECL_ALIGN (decl), (unsigned) BIGGEST_FIELD_ALIGNMENT); | |
492 | #endif | |
493 | #ifdef ADJUST_FIELD_ALIGN | |
494 | DECL_ALIGN (decl) = ADJUST_FIELD_ALIGN (decl, DECL_ALIGN (decl)); | |
495 | #endif | |
7306ed3f JW |
496 | } |
497 | } | |
498 | ||
499 | /* Evaluate nonconstant size only once, either now or as soon as safe. */ | |
500 | if (DECL_SIZE (decl) != 0 && TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST) | |
501 | DECL_SIZE (decl) = variable_size (DECL_SIZE (decl)); | |
06ceef4e RK |
502 | if (DECL_SIZE_UNIT (decl) != 0 |
503 | && TREE_CODE (DECL_SIZE_UNIT (decl)) != INTEGER_CST) | |
504 | DECL_SIZE_UNIT (decl) = variable_size (DECL_SIZE_UNIT (decl)); | |
505 | ||
506 | /* If requested, warn about definitions of large data objects. */ | |
507 | if (warn_larger_than | |
17aec3eb | 508 | && (code == VAR_DECL || code == PARM_DECL) |
06ceef4e RK |
509 | && ! DECL_EXTERNAL (decl)) |
510 | { | |
511 | tree size = DECL_SIZE_UNIT (decl); | |
512 | ||
513 | if (size != 0 && TREE_CODE (size) == INTEGER_CST | |
05bccae2 | 514 | && compare_tree_int (size, larger_than_size) > 0) |
06ceef4e | 515 | { |
0384674e | 516 | int size_as_int = TREE_INT_CST_LOW (size); |
06ceef4e | 517 | |
05bccae2 | 518 | if (compare_tree_int (size, size_as_int) == 0) |
ddd2d57e | 519 | warning ("%Jsize of '%D' is %d bytes", decl, decl, size_as_int); |
06ceef4e | 520 | else |
ddd2d57e RH |
521 | warning ("%Jsize of '%D' is larger than %d bytes", |
522 | decl, decl, larger_than_size); | |
06ceef4e RK |
523 | } |
524 | } | |
a46666a9 RH |
525 | |
526 | /* If the RTL was already set, update its mode and mem attributes. */ | |
527 | if (rtl) | |
528 | { | |
529 | PUT_MODE (rtl, DECL_MODE (decl)); | |
530 | SET_DECL_RTL (decl, 0); | |
531 | set_mem_attributes (rtl, decl, 1); | |
532 | SET_DECL_RTL (decl, rtl); | |
533 | } | |
7306ed3f JW |
534 | } |
535 | \f | |
e0cea8d9 RK |
536 | /* Hook for a front-end function that can modify the record layout as needed |
537 | immediately before it is finalized. */ | |
538 | ||
46c5ad27 | 539 | void (*lang_adjust_rli) (record_layout_info) = 0; |
e0cea8d9 RK |
540 | |
541 | void | |
46c5ad27 | 542 | set_lang_adjust_rli (void (*f) (record_layout_info)) |
e0cea8d9 RK |
543 | { |
544 | lang_adjust_rli = f; | |
545 | } | |
546 | ||
770ae6cc RK |
547 | /* Begin laying out type T, which may be a RECORD_TYPE, UNION_TYPE, or |
548 | QUAL_UNION_TYPE. Return a pointer to a struct record_layout_info which | |
549 | is to be passed to all other layout functions for this record. It is the | |
786de7eb | 550 | responsibility of the caller to call `free' for the storage returned. |
770ae6cc RK |
551 | Note that garbage collection is not permitted until we finish laying |
552 | out the record. */ | |
7306ed3f | 553 | |
9328904c | 554 | record_layout_info |
46c5ad27 | 555 | start_record_layout (tree t) |
7306ed3f | 556 | { |
703ad42b | 557 | record_layout_info rli = xmalloc (sizeof (struct record_layout_info_s)); |
9328904c MM |
558 | |
559 | rli->t = t; | |
770ae6cc | 560 | |
9328904c MM |
561 | /* If the type has a minimum specified alignment (via an attribute |
562 | declaration, for example) use it -- otherwise, start with a | |
563 | one-byte alignment. */ | |
564 | rli->record_align = MAX (BITS_PER_UNIT, TYPE_ALIGN (t)); | |
78d55cc8 | 565 | rli->unpacked_align = rli->record_align; |
770ae6cc | 566 | rli->offset_align = MAX (rli->record_align, BIGGEST_ALIGNMENT); |
7306ed3f | 567 | |
5c19a356 MS |
568 | #ifdef STRUCTURE_SIZE_BOUNDARY |
569 | /* Packed structures don't need to have minimum size. */ | |
f132af85 | 570 | if (! TYPE_PACKED (t)) |
fc555370 | 571 | rli->record_align = MAX (rli->record_align, (unsigned) STRUCTURE_SIZE_BOUNDARY); |
5c19a356 | 572 | #endif |
7306ed3f | 573 | |
770ae6cc RK |
574 | rli->offset = size_zero_node; |
575 | rli->bitpos = bitsize_zero_node; | |
f913c102 | 576 | rli->prev_field = 0; |
770ae6cc RK |
577 | rli->pending_statics = 0; |
578 | rli->packed_maybe_necessary = 0; | |
579 | ||
9328904c MM |
580 | return rli; |
581 | } | |
7306ed3f | 582 | |
f2704b9f RK |
583 | /* These four routines perform computations that convert between |
584 | the offset/bitpos forms and byte and bit offsets. */ | |
585 | ||
586 | tree | |
46c5ad27 | 587 | bit_from_pos (tree offset, tree bitpos) |
f2704b9f RK |
588 | { |
589 | return size_binop (PLUS_EXPR, bitpos, | |
590 | size_binop (MULT_EXPR, convert (bitsizetype, offset), | |
591 | bitsize_unit_node)); | |
592 | } | |
593 | ||
594 | tree | |
46c5ad27 | 595 | byte_from_pos (tree offset, tree bitpos) |
f2704b9f RK |
596 | { |
597 | return size_binop (PLUS_EXPR, offset, | |
598 | convert (sizetype, | |
f0fddb15 | 599 | size_binop (TRUNC_DIV_EXPR, bitpos, |
f2704b9f RK |
600 | bitsize_unit_node))); |
601 | } | |
602 | ||
f2704b9f | 603 | void |
46c5ad27 AJ |
604 | pos_from_bit (tree *poffset, tree *pbitpos, unsigned int off_align, |
605 | tree pos) | |
f2704b9f RK |
606 | { |
607 | *poffset = size_binop (MULT_EXPR, | |
608 | convert (sizetype, | |
609 | size_binop (FLOOR_DIV_EXPR, pos, | |
610 | bitsize_int (off_align))), | |
611 | size_int (off_align / BITS_PER_UNIT)); | |
612 | *pbitpos = size_binop (FLOOR_MOD_EXPR, pos, bitsize_int (off_align)); | |
613 | } | |
614 | ||
615 | /* Given a pointer to bit and byte offsets and an offset alignment, | |
616 | normalize the offsets so they are within the alignment. */ | |
617 | ||
618 | void | |
46c5ad27 | 619 | normalize_offset (tree *poffset, tree *pbitpos, unsigned int off_align) |
f2704b9f RK |
620 | { |
621 | /* If the bit position is now larger than it should be, adjust it | |
622 | downwards. */ | |
623 | if (compare_tree_int (*pbitpos, off_align) >= 0) | |
624 | { | |
625 | tree extra_aligns = size_binop (FLOOR_DIV_EXPR, *pbitpos, | |
626 | bitsize_int (off_align)); | |
627 | ||
628 | *poffset | |
629 | = size_binop (PLUS_EXPR, *poffset, | |
630 | size_binop (MULT_EXPR, convert (sizetype, extra_aligns), | |
631 | size_int (off_align / BITS_PER_UNIT))); | |
786de7eb | 632 | |
f2704b9f RK |
633 | *pbitpos |
634 | = size_binop (FLOOR_MOD_EXPR, *pbitpos, bitsize_int (off_align)); | |
635 | } | |
636 | } | |
637 | ||
770ae6cc | 638 | /* Print debugging information about the information in RLI. */ |
cc9d4a85 | 639 | |
770ae6cc | 640 | void |
46c5ad27 | 641 | debug_rli (record_layout_info rli) |
cc9d4a85 | 642 | { |
770ae6cc RK |
643 | print_node_brief (stderr, "type", rli->t, 0); |
644 | print_node_brief (stderr, "\noffset", rli->offset, 0); | |
645 | print_node_brief (stderr, " bitpos", rli->bitpos, 0); | |
cc9d4a85 | 646 | |
78d55cc8 JM |
647 | fprintf (stderr, "\naligns: rec = %u, unpack = %u, off = %u\n", |
648 | rli->record_align, rli->unpacked_align, | |
e0cea8d9 | 649 | rli->offset_align); |
770ae6cc RK |
650 | if (rli->packed_maybe_necessary) |
651 | fprintf (stderr, "packed may be necessary\n"); | |
652 | ||
653 | if (rli->pending_statics) | |
654 | { | |
655 | fprintf (stderr, "pending statics:\n"); | |
656 | debug_tree (rli->pending_statics); | |
657 | } | |
658 | } | |
659 | ||
660 | /* Given an RLI with a possibly-incremented BITPOS, adjust OFFSET and | |
661 | BITPOS if necessary to keep BITPOS below OFFSET_ALIGN. */ | |
662 | ||
663 | void | |
46c5ad27 | 664 | normalize_rli (record_layout_info rli) |
770ae6cc | 665 | { |
f2704b9f | 666 | normalize_offset (&rli->offset, &rli->bitpos, rli->offset_align); |
770ae6cc | 667 | } |
cc9d4a85 | 668 | |
770ae6cc RK |
669 | /* Returns the size in bytes allocated so far. */ |
670 | ||
671 | tree | |
46c5ad27 | 672 | rli_size_unit_so_far (record_layout_info rli) |
770ae6cc | 673 | { |
f2704b9f | 674 | return byte_from_pos (rli->offset, rli->bitpos); |
770ae6cc RK |
675 | } |
676 | ||
677 | /* Returns the size in bits allocated so far. */ | |
678 | ||
679 | tree | |
46c5ad27 | 680 | rli_size_so_far (record_layout_info rli) |
770ae6cc | 681 | { |
f2704b9f | 682 | return bit_from_pos (rli->offset, rli->bitpos); |
770ae6cc RK |
683 | } |
684 | ||
0645ba8f MM |
685 | /* FIELD is about to be added to RLI->T. The alignment (in bits) of |
686 | the next available location is given by KNOWN_ALIGN. Update the | |
687 | variable alignment fields in RLI, and return the alignment to give | |
688 | the FIELD. */ | |
770ae6cc | 689 | |
0645ba8f | 690 | static unsigned int |
46c5ad27 AJ |
691 | update_alignment_for_field (record_layout_info rli, tree field, |
692 | unsigned int known_align) | |
9328904c MM |
693 | { |
694 | /* The alignment required for FIELD. */ | |
695 | unsigned int desired_align; | |
9328904c MM |
696 | /* The type of this field. */ |
697 | tree type = TREE_TYPE (field); | |
0645ba8f MM |
698 | /* True if the field was explicitly aligned by the user. */ |
699 | bool user_align; | |
78d55cc8 | 700 | bool is_bitfield; |
9328904c | 701 | |
78d55cc8 JM |
702 | /* Lay out the field so we know what alignment it needs. */ |
703 | layout_decl (field, known_align); | |
770ae6cc | 704 | desired_align = DECL_ALIGN (field); |
11cf4d18 | 705 | user_align = DECL_USER_ALIGN (field); |
770ae6cc | 706 | |
78d55cc8 JM |
707 | is_bitfield = (type != error_mark_node |
708 | && DECL_BIT_FIELD_TYPE (field) | |
709 | && ! integer_zerop (TYPE_SIZE (type))); | |
7306ed3f | 710 | |
9328904c MM |
711 | /* Record must have at least as much alignment as any field. |
712 | Otherwise, the alignment of the field within the record is | |
713 | meaningless. */ | |
78d55cc8 | 714 | if (is_bitfield && (* targetm.ms_bitfield_layout_p) (rli->t)) |
f913c102 | 715 | { |
e4850f36 DR |
716 | /* Here, the alignment of the underlying type of a bitfield can |
717 | affect the alignment of a record; even a zero-sized field | |
718 | can do this. The alignment should be to the alignment of | |
719 | the type, except that for zero-size bitfields this only | |
0e9e1e0a | 720 | applies if there was an immediately prior, nonzero-size |
e4850f36 DR |
721 | bitfield. (That's the way it is, experimentally.) */ |
722 | if (! integer_zerop (DECL_SIZE (field)) | |
46c5ad27 AJ |
723 | ? ! DECL_PACKED (field) |
724 | : (rli->prev_field | |
725 | && DECL_BIT_FIELD_TYPE (rli->prev_field) | |
726 | && ! integer_zerop (DECL_SIZE (rli->prev_field)))) | |
f913c102 | 727 | { |
e4850f36 DR |
728 | unsigned int type_align = TYPE_ALIGN (type); |
729 | type_align = MAX (type_align, desired_align); | |
730 | if (maximum_field_alignment != 0) | |
731 | type_align = MIN (type_align, maximum_field_alignment); | |
732 | rli->record_align = MAX (rli->record_align, type_align); | |
f913c102 AO |
733 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
734 | } | |
786de7eb | 735 | } |
3c12fcc2 | 736 | #ifdef PCC_BITFIELD_TYPE_MATTERS |
78d55cc8 | 737 | else if (is_bitfield && PCC_BITFIELD_TYPE_MATTERS) |
9328904c | 738 | { |
8dc65b6e MM |
739 | /* Named bit-fields cause the entire structure to have the |
740 | alignment implied by their type. */ | |
9328904c | 741 | if (DECL_NAME (field) != 0) |
7306ed3f | 742 | { |
9328904c | 743 | unsigned int type_align = TYPE_ALIGN (type); |
729a2125 | 744 | |
ad9335eb JJ |
745 | #ifdef ADJUST_FIELD_ALIGN |
746 | if (! TYPE_USER_ALIGN (type)) | |
747 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
748 | #endif | |
749 | ||
9328904c MM |
750 | if (maximum_field_alignment != 0) |
751 | type_align = MIN (type_align, maximum_field_alignment); | |
752 | else if (DECL_PACKED (field)) | |
753 | type_align = MIN (type_align, BITS_PER_UNIT); | |
e2301a83 | 754 | |
8dc65b6e MM |
755 | /* The alignment of the record is increased to the maximum |
756 | of the current alignment, the alignment indicated on the | |
757 | field (i.e., the alignment specified by an __aligned__ | |
758 | attribute), and the alignment indicated by the type of | |
759 | the field. */ | |
760 | rli->record_align = MAX (rli->record_align, desired_align); | |
9328904c | 761 | rli->record_align = MAX (rli->record_align, type_align); |
8dc65b6e | 762 | |
3c12fcc2 | 763 | if (warn_packed) |
e0cea8d9 | 764 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
daf06049 | 765 | user_align |= TYPE_USER_ALIGN (type); |
3c12fcc2 | 766 | } |
9328904c | 767 | } |
9328904c | 768 | #endif |
78d55cc8 | 769 | else |
9328904c MM |
770 | { |
771 | rli->record_align = MAX (rli->record_align, desired_align); | |
770ae6cc | 772 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
9328904c | 773 | } |
3c12fcc2 | 774 | |
0645ba8f MM |
775 | TYPE_USER_ALIGN (rli->t) |= user_align; |
776 | ||
777 | return desired_align; | |
778 | } | |
779 | ||
780 | /* Called from place_field to handle unions. */ | |
781 | ||
782 | static void | |
46c5ad27 | 783 | place_union_field (record_layout_info rli, tree field) |
0645ba8f MM |
784 | { |
785 | update_alignment_for_field (rli, field, /*known_align=*/0); | |
786 | ||
787 | DECL_FIELD_OFFSET (field) = size_zero_node; | |
788 | DECL_FIELD_BIT_OFFSET (field) = bitsize_zero_node; | |
789 | SET_DECL_OFFSET_ALIGN (field, BIGGEST_ALIGNMENT); | |
790 | ||
791 | /* We assume the union's size will be a multiple of a byte so we don't | |
792 | bother with BITPOS. */ | |
793 | if (TREE_CODE (rli->t) == UNION_TYPE) | |
794 | rli->offset = size_binop (MAX_EXPR, rli->offset, DECL_SIZE_UNIT (field)); | |
795 | else if (TREE_CODE (rli->t) == QUAL_UNION_TYPE) | |
796 | rli->offset = fold (build (COND_EXPR, sizetype, | |
797 | DECL_QUALIFIER (field), | |
798 | DECL_SIZE_UNIT (field), rli->offset)); | |
799 | } | |
800 | ||
b8089d8d | 801 | #if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED) |
4977bab6 | 802 | /* A bitfield of SIZE with a required access alignment of ALIGN is allocated |
272d0bee | 803 | at BYTE_OFFSET / BIT_OFFSET. Return nonzero if the field would span more |
4977bab6 ZW |
804 | units of alignment than the underlying TYPE. */ |
805 | static int | |
46c5ad27 AJ |
806 | excess_unit_span (HOST_WIDE_INT byte_offset, HOST_WIDE_INT bit_offset, |
807 | HOST_WIDE_INT size, HOST_WIDE_INT align, tree type) | |
4977bab6 ZW |
808 | { |
809 | /* Note that the calculation of OFFSET might overflow; we calculate it so | |
810 | that we still get the right result as long as ALIGN is a power of two. */ | |
811 | unsigned HOST_WIDE_INT offset = byte_offset * BITS_PER_UNIT + bit_offset; | |
812 | ||
813 | offset = offset % align; | |
814 | return ((offset + size + align - 1) / align | |
815 | > ((unsigned HOST_WIDE_INT) tree_low_cst (TYPE_SIZE (type), 1) | |
816 | / align)); | |
817 | } | |
b8089d8d | 818 | #endif |
4977bab6 | 819 | |
0645ba8f MM |
820 | /* RLI contains information about the layout of a RECORD_TYPE. FIELD |
821 | is a FIELD_DECL to be added after those fields already present in | |
822 | T. (FIELD is not actually added to the TYPE_FIELDS list here; | |
823 | callers that desire that behavior must manually perform that step.) */ | |
824 | ||
825 | void | |
46c5ad27 | 826 | place_field (record_layout_info rli, tree field) |
0645ba8f MM |
827 | { |
828 | /* The alignment required for FIELD. */ | |
829 | unsigned int desired_align; | |
830 | /* The alignment FIELD would have if we just dropped it into the | |
831 | record as it presently stands. */ | |
832 | unsigned int known_align; | |
833 | unsigned int actual_align; | |
834 | /* The type of this field. */ | |
835 | tree type = TREE_TYPE (field); | |
836 | ||
837 | if (TREE_CODE (field) == ERROR_MARK || TREE_CODE (type) == ERROR_MARK) | |
838 | return; | |
839 | ||
840 | /* If FIELD is static, then treat it like a separate variable, not | |
841 | really like a structure field. If it is a FUNCTION_DECL, it's a | |
842 | method. In both cases, all we do is lay out the decl, and we do | |
843 | it *after* the record is laid out. */ | |
844 | if (TREE_CODE (field) == VAR_DECL) | |
845 | { | |
846 | rli->pending_statics = tree_cons (NULL_TREE, field, | |
847 | rli->pending_statics); | |
848 | return; | |
849 | } | |
850 | ||
851 | /* Enumerators and enum types which are local to this class need not | |
852 | be laid out. Likewise for initialized constant fields. */ | |
853 | else if (TREE_CODE (field) != FIELD_DECL) | |
854 | return; | |
855 | ||
856 | /* Unions are laid out very differently than records, so split | |
857 | that code off to another function. */ | |
858 | else if (TREE_CODE (rli->t) != RECORD_TYPE) | |
859 | { | |
860 | place_union_field (rli, field); | |
861 | return; | |
862 | } | |
863 | ||
864 | /* Work out the known alignment so far. Note that A & (-A) is the | |
865 | value of the least-significant bit in A that is one. */ | |
866 | if (! integer_zerop (rli->bitpos)) | |
867 | known_align = (tree_low_cst (rli->bitpos, 1) | |
868 | & - tree_low_cst (rli->bitpos, 1)); | |
869 | else if (integer_zerop (rli->offset)) | |
870 | known_align = BIGGEST_ALIGNMENT; | |
871 | else if (host_integerp (rli->offset, 1)) | |
872 | known_align = (BITS_PER_UNIT | |
873 | * (tree_low_cst (rli->offset, 1) | |
874 | & - tree_low_cst (rli->offset, 1))); | |
875 | else | |
876 | known_align = rli->offset_align; | |
46c5ad27 | 877 | |
0645ba8f MM |
878 | desired_align = update_alignment_for_field (rli, field, known_align); |
879 | ||
9328904c MM |
880 | if (warn_packed && DECL_PACKED (field)) |
881 | { | |
78d55cc8 | 882 | if (known_align >= TYPE_ALIGN (type)) |
3c12fcc2 | 883 | { |
9328904c | 884 | if (TYPE_ALIGN (type) > desired_align) |
3c12fcc2 | 885 | { |
9328904c | 886 | if (STRICT_ALIGNMENT) |
ddd2d57e RH |
887 | warning ("%Jpacked attribute causes inefficient alignment " |
888 | "for '%D'", field, field); | |
9328904c | 889 | else |
ddd2d57e RH |
890 | warning ("%Jpacked attribute is unnecessary for '%D'", |
891 | field, field); | |
3c12fcc2 | 892 | } |
3c12fcc2 | 893 | } |
9328904c MM |
894 | else |
895 | rli->packed_maybe_necessary = 1; | |
896 | } | |
7306ed3f | 897 | |
9328904c MM |
898 | /* Does this field automatically have alignment it needs by virtue |
899 | of the fields that precede it and the record's own alignment? */ | |
770ae6cc | 900 | if (known_align < desired_align) |
9328904c MM |
901 | { |
902 | /* No, we need to skip space before this field. | |
903 | Bump the cumulative size to multiple of field alignment. */ | |
7306ed3f | 904 | |
9328904c | 905 | if (warn_padded) |
ddd2d57e | 906 | warning ("%Jpadding struct to align '%D'", field, field); |
3c12fcc2 | 907 | |
770ae6cc RK |
908 | /* If the alignment is still within offset_align, just align |
909 | the bit position. */ | |
910 | if (desired_align < rli->offset_align) | |
911 | rli->bitpos = round_up (rli->bitpos, desired_align); | |
9328904c MM |
912 | else |
913 | { | |
770ae6cc RK |
914 | /* First adjust OFFSET by the partial bits, then align. */ |
915 | rli->offset | |
916 | = size_binop (PLUS_EXPR, rli->offset, | |
917 | convert (sizetype, | |
918 | size_binop (CEIL_DIV_EXPR, rli->bitpos, | |
919 | bitsize_unit_node))); | |
920 | rli->bitpos = bitsize_zero_node; | |
921 | ||
922 | rli->offset = round_up (rli->offset, desired_align / BITS_PER_UNIT); | |
7306ed3f | 923 | } |
770ae6cc | 924 | |
b1254b72 RK |
925 | if (! TREE_CONSTANT (rli->offset)) |
926 | rli->offset_align = desired_align; | |
927 | ||
9328904c | 928 | } |
7306ed3f | 929 | |
770ae6cc RK |
930 | /* Handle compatibility with PCC. Note that if the record has any |
931 | variable-sized fields, we need not worry about compatibility. */ | |
7306ed3f | 932 | #ifdef PCC_BITFIELD_TYPE_MATTERS |
9328904c | 933 | if (PCC_BITFIELD_TYPE_MATTERS |
f913c102 | 934 | && ! (* targetm.ms_bitfield_layout_p) (rli->t) |
9328904c MM |
935 | && TREE_CODE (field) == FIELD_DECL |
936 | && type != error_mark_node | |
770ae6cc RK |
937 | && DECL_BIT_FIELD (field) |
938 | && ! DECL_PACKED (field) | |
9328904c | 939 | && maximum_field_alignment == 0 |
770ae6cc RK |
940 | && ! integer_zerop (DECL_SIZE (field)) |
941 | && host_integerp (DECL_SIZE (field), 1) | |
942 | && host_integerp (rli->offset, 1) | |
943 | && host_integerp (TYPE_SIZE (type), 1)) | |
9328904c MM |
944 | { |
945 | unsigned int type_align = TYPE_ALIGN (type); | |
770ae6cc RK |
946 | tree dsize = DECL_SIZE (field); |
947 | HOST_WIDE_INT field_size = tree_low_cst (dsize, 1); | |
948 | HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0); | |
949 | HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0); | |
9328904c | 950 | |
ad9335eb JJ |
951 | #ifdef ADJUST_FIELD_ALIGN |
952 | if (! TYPE_USER_ALIGN (type)) | |
953 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
954 | #endif | |
955 | ||
9328904c MM |
956 | /* A bit field may not span more units of alignment of its type |
957 | than its type itself. Advance to next boundary if necessary. */ | |
4977bab6 | 958 | if (excess_unit_span (offset, bit_offset, field_size, type_align, type)) |
770ae6cc | 959 | rli->bitpos = round_up (rli->bitpos, type_align); |
daf06049 | 960 | |
0645ba8f | 961 | TYPE_USER_ALIGN (rli->t) |= TYPE_USER_ALIGN (type); |
9328904c | 962 | } |
7306ed3f JW |
963 | #endif |
964 | ||
7306ed3f | 965 | #ifdef BITFIELD_NBYTES_LIMITED |
9328904c | 966 | if (BITFIELD_NBYTES_LIMITED |
f913c102 | 967 | && ! (* targetm.ms_bitfield_layout_p) (rli->t) |
9328904c MM |
968 | && TREE_CODE (field) == FIELD_DECL |
969 | && type != error_mark_node | |
970 | && DECL_BIT_FIELD_TYPE (field) | |
770ae6cc RK |
971 | && ! DECL_PACKED (field) |
972 | && ! integer_zerop (DECL_SIZE (field)) | |
973 | && host_integerp (DECL_SIZE (field), 1) | |
163d3408 | 974 | && host_integerp (rli->offset, 1) |
770ae6cc | 975 | && host_integerp (TYPE_SIZE (type), 1)) |
9328904c MM |
976 | { |
977 | unsigned int type_align = TYPE_ALIGN (type); | |
770ae6cc RK |
978 | tree dsize = DECL_SIZE (field); |
979 | HOST_WIDE_INT field_size = tree_low_cst (dsize, 1); | |
980 | HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0); | |
981 | HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0); | |
e2301a83 | 982 | |
ad9335eb JJ |
983 | #ifdef ADJUST_FIELD_ALIGN |
984 | if (! TYPE_USER_ALIGN (type)) | |
985 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
986 | #endif | |
987 | ||
9328904c MM |
988 | if (maximum_field_alignment != 0) |
989 | type_align = MIN (type_align, maximum_field_alignment); | |
990 | /* ??? This test is opposite the test in the containing if | |
991 | statement, so this code is unreachable currently. */ | |
992 | else if (DECL_PACKED (field)) | |
993 | type_align = MIN (type_align, BITS_PER_UNIT); | |
994 | ||
995 | /* A bit field may not span the unit of alignment of its type. | |
996 | 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 | ||
e4850f36 DR |
1004 | /* See the docs for TARGET_MS_BITFIELD_LAYOUT_P for details. |
1005 | A subtlety: | |
1006 | When a bit field is inserted into a packed record, the whole | |
1007 | size of the underlying type is used by one or more same-size | |
4977bab6 | 1008 | adjacent bitfields. (That is, if its long:3, 32 bits is |
e4850f36 DR |
1009 | used in the record, and any additional adjacent long bitfields are |
1010 | packed into the same chunk of 32 bits. However, if the size | |
1011 | changes, a new field of that size is allocated.) In an unpacked | |
14b493d6 | 1012 | record, this is the same as using alignment, but not equivalent |
4977bab6 | 1013 | when packing. |
e4850f36 | 1014 | |
14b493d6 | 1015 | Note: for compatibility, we use the type size, not the type alignment |
e4850f36 DR |
1016 | to determine alignment, since that matches the documentation */ |
1017 | ||
f913c102 | 1018 | if ((* targetm.ms_bitfield_layout_p) (rli->t) |
e4850f36 | 1019 | && ((DECL_BIT_FIELD_TYPE (field) && ! DECL_PACKED (field)) |
46c5ad27 | 1020 | || (rli->prev_field && ! DECL_PACKED (rli->prev_field)))) |
f913c102 | 1021 | { |
e4850f36 | 1022 | /* At this point, either the prior or current are bitfields, |
991b6592 | 1023 | (possibly both), and we're dealing with MS packing. */ |
e4850f36 | 1024 | tree prev_saved = rli->prev_field; |
f913c102 | 1025 | |
e4850f36 | 1026 | /* Is the prior field a bitfield? If so, handle "runs" of same |
991b6592 KH |
1027 | type size fields. */ |
1028 | if (rli->prev_field /* necessarily a bitfield if it exists. */) | |
e4850f36 DR |
1029 | { |
1030 | /* If both are bitfields, nonzero, and the same size, this is | |
1031 | the middle of a run. Zero declared size fields are special | |
1032 | and handled as "end of run". (Note: it's nonzero declared | |
1033 | size, but equal type sizes!) (Since we know that both | |
1034 | the current and previous fields are bitfields by the | |
1035 | time we check it, DECL_SIZE must be present for both.) */ | |
1036 | if (DECL_BIT_FIELD_TYPE (field) | |
1037 | && !integer_zerop (DECL_SIZE (field)) | |
1038 | && !integer_zerop (DECL_SIZE (rli->prev_field)) | |
0384674e RK |
1039 | && host_integerp (DECL_SIZE (rli->prev_field), 0) |
1040 | && host_integerp (TYPE_SIZE (type), 0) | |
e4850f36 | 1041 | && simple_cst_equal (TYPE_SIZE (type), |
0384674e | 1042 | TYPE_SIZE (TREE_TYPE (rli->prev_field)))) |
e4850f36 DR |
1043 | { |
1044 | /* We're in the middle of a run of equal type size fields; make | |
1045 | sure we realign if we run out of bits. (Not decl size, | |
1046 | type size!) */ | |
0384674e | 1047 | HOST_WIDE_INT bitsize = tree_low_cst (DECL_SIZE (field), 0); |
e4850f36 DR |
1048 | |
1049 | if (rli->remaining_in_alignment < bitsize) | |
1050 | { | |
991b6592 | 1051 | /* out of bits; bump up to next 'word'. */ |
5354730b | 1052 | rli->offset = DECL_FIELD_OFFSET (rli->prev_field); |
0384674e RK |
1053 | rli->bitpos |
1054 | = size_binop (PLUS_EXPR, TYPE_SIZE (type), | |
1055 | DECL_FIELD_BIT_OFFSET (rli->prev_field)); | |
e4850f36 | 1056 | rli->prev_field = field; |
0384674e RK |
1057 | rli->remaining_in_alignment |
1058 | = tree_low_cst (TYPE_SIZE (type), 0); | |
e4850f36 | 1059 | } |
0384674e | 1060 | |
e4850f36 DR |
1061 | rli->remaining_in_alignment -= bitsize; |
1062 | } | |
1063 | else | |
1064 | { | |
4977bab6 ZW |
1065 | /* End of a run: if leaving a run of bitfields of the same type |
1066 | size, we have to "use up" the rest of the bits of the type | |
e4850f36 DR |
1067 | size. |
1068 | ||
1069 | Compute the new position as the sum of the size for the prior | |
1070 | type and where we first started working on that type. | |
1071 | Note: since the beginning of the field was aligned then | |
1072 | of course the end will be too. No round needed. */ | |
1073 | ||
1074 | if (!integer_zerop (DECL_SIZE (rli->prev_field))) | |
1075 | { | |
0384674e RK |
1076 | tree type_size = TYPE_SIZE (TREE_TYPE (rli->prev_field)); |
1077 | ||
1078 | rli->bitpos | |
1079 | = size_binop (PLUS_EXPR, type_size, | |
1080 | DECL_FIELD_BIT_OFFSET (rli->prev_field)); | |
e4850f36 DR |
1081 | } |
1082 | else | |
0384674e RK |
1083 | /* We "use up" size zero fields; the code below should behave |
1084 | as if the prior field was not a bitfield. */ | |
1085 | prev_saved = NULL; | |
e4850f36 | 1086 | |
4977bab6 | 1087 | /* Cause a new bitfield to be captured, either this time (if |
991b6592 | 1088 | currently a bitfield) or next time we see one. */ |
e4850f36 DR |
1089 | if (!DECL_BIT_FIELD_TYPE(field) |
1090 | || integer_zerop (DECL_SIZE (field))) | |
0384674e | 1091 | rli->prev_field = NULL; |
e4850f36 | 1092 | } |
0384674e | 1093 | |
61f71b34 | 1094 | rli->offset_align = tree_low_cst (TYPE_SIZE (type), 0); |
e4850f36 DR |
1095 | normalize_rli (rli); |
1096 | } | |
1097 | ||
1098 | /* If we're starting a new run of same size type bitfields | |
1099 | (or a run of non-bitfields), set up the "first of the run" | |
4977bab6 | 1100 | fields. |
e4850f36 DR |
1101 | |
1102 | That is, if the current field is not a bitfield, or if there | |
1103 | was a prior bitfield the type sizes differ, or if there wasn't | |
1104 | a prior bitfield the size of the current field is nonzero. | |
1105 | ||
1106 | Note: we must be sure to test ONLY the type size if there was | |
1107 | a prior bitfield and ONLY for the current field being zero if | |
1108 | there wasn't. */ | |
1109 | ||
1110 | if (!DECL_BIT_FIELD_TYPE (field) | |
4977bab6 | 1111 | || ( prev_saved != NULL |
e4850f36 | 1112 | ? !simple_cst_equal (TYPE_SIZE (type), |
0384674e RK |
1113 | TYPE_SIZE (TREE_TYPE (prev_saved))) |
1114 | : !integer_zerop (DECL_SIZE (field)) )) | |
e4850f36 | 1115 | { |
0384674e RK |
1116 | /* Never smaller than a byte for compatibility. */ |
1117 | unsigned int type_align = BITS_PER_UNIT; | |
e4850f36 | 1118 | |
4977bab6 | 1119 | /* (When not a bitfield), we could be seeing a flex array (with |
e4850f36 | 1120 | no DECL_SIZE). Since we won't be using remaining_in_alignment |
4977bab6 | 1121 | until we see a bitfield (and come by here again) we just skip |
e4850f36 | 1122 | calculating it. */ |
0384674e RK |
1123 | if (DECL_SIZE (field) != NULL |
1124 | && host_integerp (TYPE_SIZE (TREE_TYPE (field)), 0) | |
1125 | && host_integerp (DECL_SIZE (field), 0)) | |
1126 | rli->remaining_in_alignment | |
1127 | = tree_low_cst (TYPE_SIZE (TREE_TYPE(field)), 0) | |
1128 | - tree_low_cst (DECL_SIZE (field), 0); | |
e4850f36 | 1129 | |
991b6592 | 1130 | /* Now align (conventionally) for the new type. */ |
e4850f36 | 1131 | if (!DECL_PACKED(field)) |
0384674e | 1132 | type_align = MAX(TYPE_ALIGN (type), type_align); |
e4850f36 DR |
1133 | |
1134 | if (prev_saved | |
1135 | && DECL_BIT_FIELD_TYPE (prev_saved) | |
1136 | /* If the previous bit-field is zero-sized, we've already | |
1137 | accounted for its alignment needs (or ignored it, if | |
1138 | appropriate) while placing it. */ | |
1139 | && ! integer_zerop (DECL_SIZE (prev_saved))) | |
1140 | type_align = MAX (type_align, | |
1141 | TYPE_ALIGN (TREE_TYPE (prev_saved))); | |
f913c102 | 1142 | |
e4850f36 DR |
1143 | if (maximum_field_alignment != 0) |
1144 | type_align = MIN (type_align, maximum_field_alignment); | |
f913c102 | 1145 | |
e4850f36 | 1146 | rli->bitpos = round_up (rli->bitpos, type_align); |
0384674e | 1147 | |
e4850f36 | 1148 | /* If we really aligned, don't allow subsequent bitfields |
991b6592 | 1149 | to undo that. */ |
e4850f36 DR |
1150 | rli->prev_field = NULL; |
1151 | } | |
f913c102 AO |
1152 | } |
1153 | ||
770ae6cc RK |
1154 | /* Offset so far becomes the position of this field after normalizing. */ |
1155 | normalize_rli (rli); | |
1156 | DECL_FIELD_OFFSET (field) = rli->offset; | |
1157 | DECL_FIELD_BIT_OFFSET (field) = rli->bitpos; | |
2f5c7f45 | 1158 | SET_DECL_OFFSET_ALIGN (field, rli->offset_align); |
770ae6cc RK |
1159 | |
1160 | /* If this field ended up more aligned than we thought it would be (we | |
1161 | approximate this by seeing if its position changed), lay out the field | |
1162 | again; perhaps we can use an integral mode for it now. */ | |
4b6bf620 | 1163 | if (! integer_zerop (DECL_FIELD_BIT_OFFSET (field))) |
770ae6cc RK |
1164 | actual_align = (tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1) |
1165 | & - tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1)); | |
4b6bf620 RK |
1166 | else if (integer_zerop (DECL_FIELD_OFFSET (field))) |
1167 | actual_align = BIGGEST_ALIGNMENT; | |
770ae6cc RK |
1168 | else if (host_integerp (DECL_FIELD_OFFSET (field), 1)) |
1169 | actual_align = (BITS_PER_UNIT | |
1170 | * (tree_low_cst (DECL_FIELD_OFFSET (field), 1) | |
1171 | & - tree_low_cst (DECL_FIELD_OFFSET (field), 1))); | |
9328904c | 1172 | else |
770ae6cc RK |
1173 | actual_align = DECL_OFFSET_ALIGN (field); |
1174 | ||
1175 | if (known_align != actual_align) | |
1176 | layout_decl (field, actual_align); | |
1177 | ||
991b6592 | 1178 | /* Only the MS bitfields use this. */ |
e4850f36 DR |
1179 | if (rli->prev_field == NULL && DECL_BIT_FIELD_TYPE(field)) |
1180 | rli->prev_field = field; | |
f913c102 | 1181 | |
770ae6cc RK |
1182 | /* Now add size of this field to the size of the record. If the size is |
1183 | not constant, treat the field as being a multiple of bytes and just | |
1184 | adjust the offset, resetting the bit position. Otherwise, apportion the | |
1185 | size amongst the bit position and offset. First handle the case of an | |
1186 | unspecified size, which can happen when we have an invalid nested struct | |
1187 | definition, such as struct j { struct j { int i; } }. The error message | |
1188 | is printed in finish_struct. */ | |
1189 | if (DECL_SIZE (field) == 0) | |
1190 | /* Do nothing. */; | |
67011d81 RK |
1191 | else if (TREE_CODE (DECL_SIZE_UNIT (field)) != INTEGER_CST |
1192 | || TREE_CONSTANT_OVERFLOW (DECL_SIZE_UNIT (field))) | |
9328904c | 1193 | { |
770ae6cc RK |
1194 | rli->offset |
1195 | = size_binop (PLUS_EXPR, rli->offset, | |
1196 | convert (sizetype, | |
1197 | size_binop (CEIL_DIV_EXPR, rli->bitpos, | |
1198 | bitsize_unit_node))); | |
1199 | rli->offset | |
1200 | = size_binop (PLUS_EXPR, rli->offset, DECL_SIZE_UNIT (field)); | |
1201 | rli->bitpos = bitsize_zero_node; | |
3923e410 | 1202 | rli->offset_align = MIN (rli->offset_align, desired_align); |
9328904c | 1203 | } |
9328904c MM |
1204 | else |
1205 | { | |
770ae6cc RK |
1206 | rli->bitpos = size_binop (PLUS_EXPR, rli->bitpos, DECL_SIZE (field)); |
1207 | normalize_rli (rli); | |
7306ed3f | 1208 | } |
9328904c | 1209 | } |
7306ed3f | 1210 | |
9328904c MM |
1211 | /* Assuming that all the fields have been laid out, this function uses |
1212 | RLI to compute the final TYPE_SIZE, TYPE_ALIGN, etc. for the type | |
14b493d6 | 1213 | indicated by RLI. */ |
7306ed3f | 1214 | |
9328904c | 1215 | static void |
46c5ad27 | 1216 | finalize_record_size (record_layout_info rli) |
9328904c | 1217 | { |
770ae6cc RK |
1218 | tree unpadded_size, unpadded_size_unit; |
1219 | ||
65e14bf5 RK |
1220 | /* Now we want just byte and bit offsets, so set the offset alignment |
1221 | to be a byte and then normalize. */ | |
1222 | rli->offset_align = BITS_PER_UNIT; | |
1223 | normalize_rli (rli); | |
7306ed3f JW |
1224 | |
1225 | /* Determine the desired alignment. */ | |
1226 | #ifdef ROUND_TYPE_ALIGN | |
9328904c | 1227 | TYPE_ALIGN (rli->t) = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t), |
b451555a | 1228 | rli->record_align); |
7306ed3f | 1229 | #else |
9328904c | 1230 | TYPE_ALIGN (rli->t) = MAX (TYPE_ALIGN (rli->t), rli->record_align); |
7306ed3f JW |
1231 | #endif |
1232 | ||
65e14bf5 RK |
1233 | /* Compute the size so far. Be sure to allow for extra bits in the |
1234 | size in bytes. We have guaranteed above that it will be no more | |
1235 | than a single byte. */ | |
1236 | unpadded_size = rli_size_so_far (rli); | |
1237 | unpadded_size_unit = rli_size_unit_so_far (rli); | |
1238 | if (! integer_zerop (rli->bitpos)) | |
1239 | unpadded_size_unit | |
1240 | = size_binop (PLUS_EXPR, unpadded_size_unit, size_one_node); | |
770ae6cc | 1241 | |
f9da5064 | 1242 | /* Round the size up to be a multiple of the required alignment. */ |
770ae6cc RK |
1243 | TYPE_SIZE (rli->t) = round_up (unpadded_size, TYPE_ALIGN (rli->t)); |
1244 | TYPE_SIZE_UNIT (rli->t) = round_up (unpadded_size_unit, | |
1245 | TYPE_ALIGN (rli->t) / BITS_PER_UNIT); | |
729a2125 | 1246 | |
770ae6cc RK |
1247 | if (warn_padded && TREE_CONSTANT (unpadded_size) |
1248 | && simple_cst_equal (unpadded_size, TYPE_SIZE (rli->t)) == 0) | |
1249 | warning ("padding struct size to alignment boundary"); | |
786de7eb | 1250 | |
770ae6cc RK |
1251 | if (warn_packed && TREE_CODE (rli->t) == RECORD_TYPE |
1252 | && TYPE_PACKED (rli->t) && ! rli->packed_maybe_necessary | |
1253 | && TREE_CONSTANT (unpadded_size)) | |
3c12fcc2 GM |
1254 | { |
1255 | tree unpacked_size; | |
729a2125 | 1256 | |
3c12fcc2 | 1257 | #ifdef ROUND_TYPE_ALIGN |
9328904c MM |
1258 | rli->unpacked_align |
1259 | = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t), rli->unpacked_align); | |
3c12fcc2 | 1260 | #else |
9328904c | 1261 | rli->unpacked_align = MAX (TYPE_ALIGN (rli->t), rli->unpacked_align); |
3c12fcc2 | 1262 | #endif |
770ae6cc | 1263 | |
9328904c | 1264 | unpacked_size = round_up (TYPE_SIZE (rli->t), rli->unpacked_align); |
9328904c | 1265 | if (simple_cst_equal (unpacked_size, TYPE_SIZE (rli->t))) |
3c12fcc2 | 1266 | { |
770ae6cc RK |
1267 | TYPE_PACKED (rli->t) = 0; |
1268 | ||
9328904c | 1269 | if (TYPE_NAME (rli->t)) |
3c12fcc2 | 1270 | { |
63ad61ed | 1271 | const char *name; |
729a2125 | 1272 | |
9328904c MM |
1273 | if (TREE_CODE (TYPE_NAME (rli->t)) == IDENTIFIER_NODE) |
1274 | name = IDENTIFIER_POINTER (TYPE_NAME (rli->t)); | |
3c12fcc2 | 1275 | else |
9328904c | 1276 | name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (rli->t))); |
770ae6cc | 1277 | |
3c12fcc2 GM |
1278 | if (STRICT_ALIGNMENT) |
1279 | warning ("packed attribute causes inefficient alignment for `%s'", name); | |
1280 | else | |
1281 | warning ("packed attribute is unnecessary for `%s'", name); | |
1282 | } | |
1283 | else | |
1284 | { | |
1285 | if (STRICT_ALIGNMENT) | |
1286 | warning ("packed attribute causes inefficient alignment"); | |
1287 | else | |
1288 | warning ("packed attribute is unnecessary"); | |
1289 | } | |
1290 | } | |
3c12fcc2 | 1291 | } |
9328904c MM |
1292 | } |
1293 | ||
1294 | /* Compute the TYPE_MODE for the TYPE (which is a RECORD_TYPE). */ | |
7306ed3f | 1295 | |
65e14bf5 | 1296 | void |
46c5ad27 | 1297 | compute_record_mode (tree type) |
9328904c | 1298 | { |
770ae6cc RK |
1299 | tree field; |
1300 | enum machine_mode mode = VOIDmode; | |
1301 | ||
9328904c MM |
1302 | /* Most RECORD_TYPEs have BLKmode, so we start off assuming that. |
1303 | However, if possible, we use a mode that fits in a register | |
1304 | instead, in order to allow for better optimization down the | |
1305 | line. */ | |
1306 | TYPE_MODE (type) = BLKmode; | |
9328904c | 1307 | |
770ae6cc RK |
1308 | if (! host_integerp (TYPE_SIZE (type), 1)) |
1309 | return; | |
9328904c | 1310 | |
770ae6cc RK |
1311 | /* A record which has any BLKmode members must itself be |
1312 | BLKmode; it can't go in a register. Unless the member is | |
1313 | BLKmode only because it isn't aligned. */ | |
1314 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) | |
1315 | { | |
770ae6cc RK |
1316 | if (TREE_CODE (field) != FIELD_DECL) |
1317 | continue; | |
9328904c | 1318 | |
770ae6cc RK |
1319 | if (TREE_CODE (TREE_TYPE (field)) == ERROR_MARK |
1320 | || (TYPE_MODE (TREE_TYPE (field)) == BLKmode | |
7a06d606 RK |
1321 | && ! TYPE_NO_FORCE_BLK (TREE_TYPE (field)) |
1322 | && !(TYPE_SIZE (TREE_TYPE (field)) != 0 | |
1323 | && integer_zerop (TYPE_SIZE (TREE_TYPE (field))))) | |
770ae6cc | 1324 | || ! host_integerp (bit_position (field), 1) |
6a9f6727 | 1325 | || DECL_SIZE (field) == 0 |
770ae6cc RK |
1326 | || ! host_integerp (DECL_SIZE (field), 1)) |
1327 | return; | |
1328 | ||
770ae6cc RK |
1329 | /* If this field is the whole struct, remember its mode so |
1330 | that, say, we can put a double in a class into a DF | |
a8ca7756 JW |
1331 | register instead of forcing it to live in the stack. */ |
1332 | if (simple_cst_equal (TYPE_SIZE (type), DECL_SIZE (field))) | |
770ae6cc | 1333 | mode = DECL_MODE (field); |
9328904c | 1334 | |
31a02448 | 1335 | #ifdef MEMBER_TYPE_FORCES_BLK |
770ae6cc RK |
1336 | /* With some targets, eg. c4x, it is sub-optimal |
1337 | to access an aligned BLKmode structure as a scalar. */ | |
0d7839da | 1338 | |
182e515e | 1339 | if (MEMBER_TYPE_FORCES_BLK (field, mode)) |
770ae6cc | 1340 | return; |
31a02448 | 1341 | #endif /* MEMBER_TYPE_FORCES_BLK */ |
770ae6cc | 1342 | } |
9328904c | 1343 | |
a8ca7756 JW |
1344 | /* If we only have one real field; use its mode. This only applies to |
1345 | RECORD_TYPE. This does not apply to unions. */ | |
1346 | if (TREE_CODE (type) == RECORD_TYPE && mode != VOIDmode) | |
770ae6cc RK |
1347 | TYPE_MODE (type) = mode; |
1348 | else | |
1349 | TYPE_MODE (type) = mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1); | |
1350 | ||
1351 | /* If structure's known alignment is less than what the scalar | |
1352 | mode would need, and it matters, then stick with BLKmode. */ | |
1353 | if (TYPE_MODE (type) != BLKmode | |
1354 | && STRICT_ALIGNMENT | |
1355 | && ! (TYPE_ALIGN (type) >= BIGGEST_ALIGNMENT | |
1356 | || TYPE_ALIGN (type) >= GET_MODE_ALIGNMENT (TYPE_MODE (type)))) | |
1357 | { | |
1358 | /* If this is the only reason this type is BLKmode, then | |
1359 | don't force containing types to be BLKmode. */ | |
1360 | TYPE_NO_FORCE_BLK (type) = 1; | |
1361 | TYPE_MODE (type) = BLKmode; | |
9328904c | 1362 | } |
7306ed3f | 1363 | } |
9328904c MM |
1364 | |
1365 | /* Compute TYPE_SIZE and TYPE_ALIGN for TYPE, once it has been laid | |
1366 | out. */ | |
1367 | ||
1368 | static void | |
46c5ad27 | 1369 | finalize_type_size (tree type) |
9328904c MM |
1370 | { |
1371 | /* Normally, use the alignment corresponding to the mode chosen. | |
1372 | However, where strict alignment is not required, avoid | |
1373 | over-aligning structures, since most compilers do not do this | |
1374 | alignment. */ | |
1375 | ||
1376 | if (TYPE_MODE (type) != BLKmode && TYPE_MODE (type) != VOIDmode | |
1377 | && (STRICT_ALIGNMENT | |
1378 | || (TREE_CODE (type) != RECORD_TYPE && TREE_CODE (type) != UNION_TYPE | |
1379 | && TREE_CODE (type) != QUAL_UNION_TYPE | |
1380 | && TREE_CODE (type) != ARRAY_TYPE))) | |
11cf4d18 JJ |
1381 | { |
1382 | TYPE_ALIGN (type) = GET_MODE_ALIGNMENT (TYPE_MODE (type)); | |
1383 | TYPE_USER_ALIGN (type) = 0; | |
1384 | } | |
9328904c MM |
1385 | |
1386 | /* Do machine-dependent extra alignment. */ | |
1387 | #ifdef ROUND_TYPE_ALIGN | |
1388 | TYPE_ALIGN (type) | |
1389 | = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (type), BITS_PER_UNIT); | |
1390 | #endif | |
1391 | ||
9328904c | 1392 | /* If we failed to find a simple way to calculate the unit size |
770ae6cc | 1393 | of the type, find it by division. */ |
9328904c MM |
1394 | if (TYPE_SIZE_UNIT (type) == 0 && TYPE_SIZE (type) != 0) |
1395 | /* TYPE_SIZE (type) is computed in bitsizetype. After the division, the | |
1396 | result will fit in sizetype. We will get more efficient code using | |
1397 | sizetype, so we force a conversion. */ | |
1398 | TYPE_SIZE_UNIT (type) | |
1399 | = convert (sizetype, | |
1400 | size_binop (FLOOR_DIV_EXPR, TYPE_SIZE (type), | |
770ae6cc | 1401 | bitsize_unit_node)); |
9328904c | 1402 | |
770ae6cc RK |
1403 | if (TYPE_SIZE (type) != 0) |
1404 | { | |
770ae6cc RK |
1405 | TYPE_SIZE (type) = round_up (TYPE_SIZE (type), TYPE_ALIGN (type)); |
1406 | TYPE_SIZE_UNIT (type) | |
1407 | = round_up (TYPE_SIZE_UNIT (type), TYPE_ALIGN (type) / BITS_PER_UNIT); | |
770ae6cc RK |
1408 | } |
1409 | ||
1410 | /* Evaluate nonconstant sizes only once, either now or as soon as safe. */ | |
1411 | if (TYPE_SIZE (type) != 0 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) | |
1412 | TYPE_SIZE (type) = variable_size (TYPE_SIZE (type)); | |
9328904c MM |
1413 | if (TYPE_SIZE_UNIT (type) != 0 |
1414 | && TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST) | |
1415 | TYPE_SIZE_UNIT (type) = variable_size (TYPE_SIZE_UNIT (type)); | |
1416 | ||
1417 | /* Also layout any other variants of the type. */ | |
1418 | if (TYPE_NEXT_VARIANT (type) | |
1419 | || type != TYPE_MAIN_VARIANT (type)) | |
1420 | { | |
1421 | tree variant; | |
1422 | /* Record layout info of this variant. */ | |
1423 | tree size = TYPE_SIZE (type); | |
1424 | tree size_unit = TYPE_SIZE_UNIT (type); | |
1425 | unsigned int align = TYPE_ALIGN (type); | |
11cf4d18 | 1426 | unsigned int user_align = TYPE_USER_ALIGN (type); |
9328904c MM |
1427 | enum machine_mode mode = TYPE_MODE (type); |
1428 | ||
1429 | /* Copy it into all variants. */ | |
1430 | for (variant = TYPE_MAIN_VARIANT (type); | |
1431 | variant != 0; | |
1432 | variant = TYPE_NEXT_VARIANT (variant)) | |
1433 | { | |
1434 | TYPE_SIZE (variant) = size; | |
1435 | TYPE_SIZE_UNIT (variant) = size_unit; | |
1436 | TYPE_ALIGN (variant) = align; | |
11cf4d18 | 1437 | TYPE_USER_ALIGN (variant) = user_align; |
9328904c MM |
1438 | TYPE_MODE (variant) = mode; |
1439 | } | |
1440 | } | |
1441 | } | |
1442 | ||
1443 | /* Do all of the work required to layout the type indicated by RLI, | |
1444 | once the fields have been laid out. This function will call `free' | |
17bbb839 MM |
1445 | for RLI, unless FREE_P is false. Passing a value other than false |
1446 | for FREE_P is bad practice; this option only exists to support the | |
1447 | G++ 3.2 ABI. */ | |
9328904c MM |
1448 | |
1449 | void | |
46c5ad27 | 1450 | finish_record_layout (record_layout_info rli, int free_p) |
9328904c | 1451 | { |
770ae6cc RK |
1452 | /* Compute the final size. */ |
1453 | finalize_record_size (rli); | |
1454 | ||
1455 | /* Compute the TYPE_MODE for the record. */ | |
1456 | compute_record_mode (rli->t); | |
cc9d4a85 | 1457 | |
8d8238b6 JM |
1458 | /* Perform any last tweaks to the TYPE_SIZE, etc. */ |
1459 | finalize_type_size (rli->t); | |
1460 | ||
9328904c MM |
1461 | /* Lay out any static members. This is done now because their type |
1462 | may use the record's type. */ | |
1463 | while (rli->pending_statics) | |
1464 | { | |
1465 | layout_decl (TREE_VALUE (rli->pending_statics), 0); | |
1466 | rli->pending_statics = TREE_CHAIN (rli->pending_statics); | |
1467 | } | |
cc9d4a85 | 1468 | |
9328904c | 1469 | /* Clean up. */ |
17bbb839 MM |
1470 | if (free_p) |
1471 | free (rli); | |
9328904c | 1472 | } |
7306ed3f | 1473 | \f |
4977bab6 ZW |
1474 | |
1475 | /* Finish processing a builtin RECORD_TYPE type TYPE. It's name is | |
1476 | NAME, its fields are chained in reverse on FIELDS. | |
1477 | ||
1478 | If ALIGN_TYPE is non-null, it is given the same alignment as | |
1479 | ALIGN_TYPE. */ | |
1480 | ||
1481 | void | |
46c5ad27 AJ |
1482 | finish_builtin_struct (tree type, const char *name, tree fields, |
1483 | tree align_type) | |
4977bab6 ZW |
1484 | { |
1485 | tree tail, next; | |
1486 | ||
1487 | for (tail = NULL_TREE; fields; tail = fields, fields = next) | |
1488 | { | |
1489 | DECL_FIELD_CONTEXT (fields) = type; | |
1490 | next = TREE_CHAIN (fields); | |
1491 | TREE_CHAIN (fields) = tail; | |
1492 | } | |
1493 | TYPE_FIELDS (type) = tail; | |
1494 | ||
1495 | if (align_type) | |
1496 | { | |
1497 | TYPE_ALIGN (type) = TYPE_ALIGN (align_type); | |
1498 | TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (align_type); | |
1499 | } | |
1500 | ||
1501 | layout_type (type); | |
1502 | #if 0 /* not yet, should get fixed properly later */ | |
1503 | TYPE_NAME (type) = make_type_decl (get_identifier (name), type); | |
1504 | #else | |
1505 | TYPE_NAME (type) = build_decl (TYPE_DECL, get_identifier (name), type); | |
1506 | #endif | |
1507 | TYPE_STUB_DECL (type) = TYPE_NAME (type); | |
1508 | layout_decl (TYPE_NAME (type), 0); | |
1509 | } | |
1510 | ||
7306ed3f JW |
1511 | /* Calculate the mode, size, and alignment for TYPE. |
1512 | For an array type, calculate the element separation as well. | |
1513 | Record TYPE on the chain of permanent or temporary types | |
1514 | so that dbxout will find out about it. | |
1515 | ||
1516 | TYPE_SIZE of a type is nonzero if the type has been laid out already. | |
1517 | layout_type does nothing on such a type. | |
1518 | ||
1519 | If the type is incomplete, its TYPE_SIZE remains zero. */ | |
1520 | ||
1521 | void | |
46c5ad27 | 1522 | layout_type (tree type) |
7306ed3f | 1523 | { |
7306ed3f JW |
1524 | if (type == 0) |
1525 | abort (); | |
1526 | ||
1527 | /* Do nothing if type has been laid out before. */ | |
1528 | if (TYPE_SIZE (type)) | |
1529 | return; | |
1530 | ||
7306ed3f JW |
1531 | switch (TREE_CODE (type)) |
1532 | { | |
1533 | case LANG_TYPE: | |
1534 | /* This kind of type is the responsibility | |
9faa82d8 | 1535 | of the language-specific code. */ |
7306ed3f JW |
1536 | abort (); |
1537 | ||
2d76cb1a | 1538 | case BOOLEAN_TYPE: /* Used for Java, Pascal, and Chill. */ |
e9a25f70 | 1539 | if (TYPE_PRECISION (type) == 0) |
2d76cb1a | 1540 | TYPE_PRECISION (type) = 1; /* default to one byte/boolean. */ |
d4b60170 | 1541 | |
2d76cb1a | 1542 | /* ... fall through ... */ |
e9a25f70 | 1543 | |
7306ed3f JW |
1544 | case INTEGER_TYPE: |
1545 | case ENUMERAL_TYPE: | |
fc69eca0 | 1546 | case CHAR_TYPE: |
e2a77f99 RK |
1547 | if (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST |
1548 | && tree_int_cst_sgn (TYPE_MIN_VALUE (type)) >= 0) | |
7306ed3f JW |
1549 | TREE_UNSIGNED (type) = 1; |
1550 | ||
5e9bec99 RK |
1551 | TYPE_MODE (type) = smallest_mode_for_size (TYPE_PRECISION (type), |
1552 | MODE_INT); | |
06ceef4e | 1553 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1554 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1555 | break; |
1556 | ||
1557 | case REAL_TYPE: | |
1558 | TYPE_MODE (type) = mode_for_size (TYPE_PRECISION (type), MODE_FLOAT, 0); | |
06ceef4e | 1559 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1560 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1561 | break; |
1562 | ||
1563 | case COMPLEX_TYPE: | |
1564 | TREE_UNSIGNED (type) = TREE_UNSIGNED (TREE_TYPE (type)); | |
1565 | TYPE_MODE (type) | |
1566 | = mode_for_size (2 * TYPE_PRECISION (TREE_TYPE (type)), | |
1567 | (TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE | |
1568 | ? MODE_COMPLEX_INT : MODE_COMPLEX_FLOAT), | |
1569 | 0); | |
06ceef4e | 1570 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1571 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1572 | break; |
1573 | ||
0b4565c9 BS |
1574 | case VECTOR_TYPE: |
1575 | { | |
1576 | tree subtype; | |
1577 | ||
1578 | subtype = TREE_TYPE (type); | |
1579 | TREE_UNSIGNED (type) = TREE_UNSIGNED (subtype); | |
1580 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); | |
1581 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); | |
1582 | } | |
1583 | break; | |
1584 | ||
7306ed3f | 1585 | case VOID_TYPE: |
770ae6cc | 1586 | /* This is an incomplete type and so doesn't have a size. */ |
7306ed3f | 1587 | TYPE_ALIGN (type) = 1; |
11cf4d18 | 1588 | TYPE_USER_ALIGN (type) = 0; |
7306ed3f JW |
1589 | TYPE_MODE (type) = VOIDmode; |
1590 | break; | |
1591 | ||
321cb743 | 1592 | case OFFSET_TYPE: |
06ceef4e | 1593 | TYPE_SIZE (type) = bitsize_int (POINTER_SIZE); |
ead17059 | 1594 | TYPE_SIZE_UNIT (type) = size_int (POINTER_SIZE / BITS_PER_UNIT); |
25caaba8 R |
1595 | /* A pointer might be MODE_PARTIAL_INT, |
1596 | but ptrdiff_t must be integral. */ | |
1597 | TYPE_MODE (type) = mode_for_size (POINTER_SIZE, MODE_INT, 0); | |
321cb743 MT |
1598 | break; |
1599 | ||
7306ed3f JW |
1600 | case FUNCTION_TYPE: |
1601 | case METHOD_TYPE: | |
13275056 | 1602 | TYPE_MODE (type) = mode_for_size (2 * POINTER_SIZE, MODE_INT, 0); |
06ceef4e | 1603 | TYPE_SIZE (type) = bitsize_int (2 * POINTER_SIZE); |
ead17059 | 1604 | TYPE_SIZE_UNIT (type) = size_int ((2 * POINTER_SIZE) / BITS_PER_UNIT); |
7306ed3f JW |
1605 | break; |
1606 | ||
1607 | case POINTER_TYPE: | |
1608 | case REFERENCE_TYPE: | |
b5d6a2ff | 1609 | { |
b5d6a2ff | 1610 | |
4977bab6 ZW |
1611 | enum machine_mode mode = ((TREE_CODE (type) == REFERENCE_TYPE |
1612 | && reference_types_internal) | |
1613 | ? Pmode : TYPE_MODE (type)); | |
1614 | ||
1615 | int nbits = GET_MODE_BITSIZE (mode); | |
1616 | ||
b5d6a2ff | 1617 | TYPE_SIZE (type) = bitsize_int (nbits); |
4977bab6 | 1618 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (mode)); |
b5d6a2ff RK |
1619 | TREE_UNSIGNED (type) = 1; |
1620 | TYPE_PRECISION (type) = nbits; | |
1621 | } | |
7306ed3f JW |
1622 | break; |
1623 | ||
1624 | case ARRAY_TYPE: | |
1625 | { | |
b3694847 SS |
1626 | tree index = TYPE_DOMAIN (type); |
1627 | tree element = TREE_TYPE (type); | |
7306ed3f JW |
1628 | |
1629 | build_pointer_type (element); | |
1630 | ||
1631 | /* We need to know both bounds in order to compute the size. */ | |
1632 | if (index && TYPE_MAX_VALUE (index) && TYPE_MIN_VALUE (index) | |
1633 | && TYPE_SIZE (element)) | |
1634 | { | |
e24ff973 RK |
1635 | tree ub = TYPE_MAX_VALUE (index); |
1636 | tree lb = TYPE_MIN_VALUE (index); | |
1637 | tree length; | |
74a4fbfc | 1638 | tree element_size; |
e24ff973 | 1639 | |
a2d53b28 RH |
1640 | /* The initial subtraction should happen in the original type so |
1641 | that (possible) negative values are handled appropriately. */ | |
e24ff973 | 1642 | length = size_binop (PLUS_EXPR, size_one_node, |
fed3cef0 RK |
1643 | convert (sizetype, |
1644 | fold (build (MINUS_EXPR, | |
1645 | TREE_TYPE (lb), | |
1646 | ub, lb)))); | |
7306ed3f | 1647 | |
74a4fbfc DB |
1648 | /* Special handling for arrays of bits (for Chill). */ |
1649 | element_size = TYPE_SIZE (element); | |
382110c0 RK |
1650 | if (TYPE_PACKED (type) && INTEGRAL_TYPE_P (element) |
1651 | && (integer_zerop (TYPE_MAX_VALUE (element)) | |
1652 | || integer_onep (TYPE_MAX_VALUE (element))) | |
1653 | && host_integerp (TYPE_MIN_VALUE (element), 1)) | |
74a4fbfc | 1654 | { |
d4b60170 | 1655 | HOST_WIDE_INT maxvalue |
382110c0 | 1656 | = tree_low_cst (TYPE_MAX_VALUE (element), 1); |
d4b60170 | 1657 | HOST_WIDE_INT minvalue |
382110c0 | 1658 | = tree_low_cst (TYPE_MIN_VALUE (element), 1); |
d4b60170 | 1659 | |
74a4fbfc DB |
1660 | if (maxvalue - minvalue == 1 |
1661 | && (maxvalue == 1 || maxvalue == 0)) | |
1662 | element_size = integer_one_node; | |
1663 | } | |
1664 | ||
0d3c8800 RK |
1665 | /* If neither bound is a constant and sizetype is signed, make |
1666 | sure the size is never negative. We should really do this | |
1667 | if *either* bound is non-constant, but this is the best | |
1668 | compromise between C and Ada. */ | |
1669 | if (! TREE_UNSIGNED (sizetype) | |
1670 | && TREE_CODE (TYPE_MIN_VALUE (index)) != INTEGER_CST | |
1671 | && TREE_CODE (TYPE_MAX_VALUE (index)) != INTEGER_CST) | |
1672 | length = size_binop (MAX_EXPR, length, size_zero_node); | |
1673 | ||
fed3cef0 RK |
1674 | TYPE_SIZE (type) = size_binop (MULT_EXPR, element_size, |
1675 | convert (bitsizetype, length)); | |
ead17059 RH |
1676 | |
1677 | /* If we know the size of the element, calculate the total | |
1678 | size directly, rather than do some division thing below. | |
1679 | This optimization helps Fortran assumed-size arrays | |
1680 | (where the size of the array is determined at runtime) | |
7771032e DB |
1681 | substantially. |
1682 | Note that we can't do this in the case where the size of | |
1683 | the elements is one bit since TYPE_SIZE_UNIT cannot be | |
1684 | set correctly in that case. */ | |
fed3cef0 | 1685 | if (TYPE_SIZE_UNIT (element) != 0 && ! integer_onep (element_size)) |
d4b60170 RK |
1686 | TYPE_SIZE_UNIT (type) |
1687 | = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (element), length); | |
7306ed3f JW |
1688 | } |
1689 | ||
1690 | /* Now round the alignment and size, | |
1691 | using machine-dependent criteria if any. */ | |
1692 | ||
1693 | #ifdef ROUND_TYPE_ALIGN | |
1694 | TYPE_ALIGN (type) | |
1695 | = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (element), BITS_PER_UNIT); | |
1696 | #else | |
1697 | TYPE_ALIGN (type) = MAX (TYPE_ALIGN (element), BITS_PER_UNIT); | |
1698 | #endif | |
c163d21d | 1699 | TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (element); |
7306ed3f JW |
1700 | TYPE_MODE (type) = BLKmode; |
1701 | if (TYPE_SIZE (type) != 0 | |
31a02448 | 1702 | #ifdef MEMBER_TYPE_FORCES_BLK |
182e515e | 1703 | && ! MEMBER_TYPE_FORCES_BLK (type, VOIDmode) |
31a02448 | 1704 | #endif |
7306ed3f JW |
1705 | /* BLKmode elements force BLKmode aggregate; |
1706 | else extract/store fields may lose. */ | |
1707 | && (TYPE_MODE (TREE_TYPE (type)) != BLKmode | |
1708 | || TYPE_NO_FORCE_BLK (TREE_TYPE (type)))) | |
1709 | { | |
a1471322 RK |
1710 | /* One-element arrays get the component type's mode. */ |
1711 | if (simple_cst_equal (TYPE_SIZE (type), | |
1712 | TYPE_SIZE (TREE_TYPE (type)))) | |
1713 | TYPE_MODE (type) = TYPE_MODE (TREE_TYPE (type)); | |
1714 | else | |
1715 | TYPE_MODE (type) | |
1716 | = mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1); | |
7306ed3f | 1717 | |
72c602fc RK |
1718 | if (TYPE_MODE (type) != BLKmode |
1719 | && STRICT_ALIGNMENT && TYPE_ALIGN (type) < BIGGEST_ALIGNMENT | |
1720 | && TYPE_ALIGN (type) < GET_MODE_ALIGNMENT (TYPE_MODE (type)) | |
7306ed3f JW |
1721 | && TYPE_MODE (type) != BLKmode) |
1722 | { | |
1723 | TYPE_NO_FORCE_BLK (type) = 1; | |
1724 | TYPE_MODE (type) = BLKmode; | |
1725 | } | |
7306ed3f JW |
1726 | } |
1727 | break; | |
1728 | } | |
1729 | ||
1730 | case RECORD_TYPE: | |
cc9d4a85 MM |
1731 | case UNION_TYPE: |
1732 | case QUAL_UNION_TYPE: | |
9328904c MM |
1733 | { |
1734 | tree field; | |
1735 | record_layout_info rli; | |
1736 | ||
1737 | /* Initialize the layout information. */ | |
770ae6cc RK |
1738 | rli = start_record_layout (type); |
1739 | ||
cc9d4a85 MM |
1740 | /* If this is a QUAL_UNION_TYPE, we want to process the fields |
1741 | in the reverse order in building the COND_EXPR that denotes | |
1742 | its size. We reverse them again later. */ | |
1743 | if (TREE_CODE (type) == QUAL_UNION_TYPE) | |
1744 | TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type)); | |
770ae6cc RK |
1745 | |
1746 | /* Place all the fields. */ | |
9328904c | 1747 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) |
770ae6cc RK |
1748 | place_field (rli, field); |
1749 | ||
cc9d4a85 MM |
1750 | if (TREE_CODE (type) == QUAL_UNION_TYPE) |
1751 | TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type)); | |
770ae6cc | 1752 | |
e0cea8d9 RK |
1753 | if (lang_adjust_rli) |
1754 | (*lang_adjust_rli) (rli); | |
1755 | ||
9328904c | 1756 | /* Finish laying out the record. */ |
17bbb839 | 1757 | finish_record_layout (rli, /*free_p=*/true); |
9328904c | 1758 | } |
7306ed3f JW |
1759 | break; |
1760 | ||
2d76cb1a | 1761 | case SET_TYPE: /* Used by Chill and Pascal. */ |
b5d11e41 PB |
1762 | if (TREE_CODE (TYPE_MAX_VALUE (TYPE_DOMAIN (type))) != INTEGER_CST |
1763 | || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (type))) != INTEGER_CST) | |
cf403648 | 1764 | abort (); |
b5d11e41 PB |
1765 | else |
1766 | { | |
1767 | #ifndef SET_WORD_SIZE | |
1768 | #define SET_WORD_SIZE BITS_PER_WORD | |
1769 | #endif | |
729a2125 RK |
1770 | unsigned int alignment |
1771 | = set_alignment ? set_alignment : SET_WORD_SIZE; | |
0384674e RK |
1772 | HOST_WIDE_INT size_in_bits |
1773 | = (tree_low_cst (TYPE_MAX_VALUE (TYPE_DOMAIN (type)), 0) | |
1774 | - tree_low_cst (TYPE_MIN_VALUE (TYPE_DOMAIN (type)), 0) + 1); | |
1775 | HOST_WIDE_INT rounded_size | |
b5d11e41 | 1776 | = ((size_in_bits + alignment - 1) / alignment) * alignment; |
729a2125 RK |
1777 | |
1778 | if (rounded_size > (int) alignment) | |
b5d11e41 PB |
1779 | TYPE_MODE (type) = BLKmode; |
1780 | else | |
1781 | TYPE_MODE (type) = mode_for_size (alignment, MODE_INT, 1); | |
729a2125 | 1782 | |
06ceef4e | 1783 | TYPE_SIZE (type) = bitsize_int (rounded_size); |
ead17059 | 1784 | TYPE_SIZE_UNIT (type) = size_int (rounded_size / BITS_PER_UNIT); |
b5d11e41 | 1785 | TYPE_ALIGN (type) = alignment; |
11cf4d18 | 1786 | TYPE_USER_ALIGN (type) = 0; |
b5d11e41 PB |
1787 | TYPE_PRECISION (type) = size_in_bits; |
1788 | } | |
1789 | break; | |
1790 | ||
4cc89e53 RS |
1791 | case FILE_TYPE: |
1792 | /* The size may vary in different languages, so the language front end | |
1793 | should fill in the size. */ | |
1794 | TYPE_ALIGN (type) = BIGGEST_ALIGNMENT; | |
11cf4d18 | 1795 | TYPE_USER_ALIGN (type) = 0; |
4cc89e53 RS |
1796 | TYPE_MODE (type) = BLKmode; |
1797 | break; | |
1798 | ||
7306ed3f JW |
1799 | default: |
1800 | abort (); | |
729a2125 | 1801 | } |
7306ed3f | 1802 | |
9328904c | 1803 | /* Compute the final TYPE_SIZE, TYPE_ALIGN, etc. for TYPE. For |
cc9d4a85 MM |
1804 | records and unions, finish_record_layout already called this |
1805 | function. */ | |
786de7eb | 1806 | if (TREE_CODE (type) != RECORD_TYPE |
cc9d4a85 MM |
1807 | && TREE_CODE (type) != UNION_TYPE |
1808 | && TREE_CODE (type) != QUAL_UNION_TYPE) | |
9328904c | 1809 | finalize_type_size (type); |
7306ed3f | 1810 | |
fed3cef0 RK |
1811 | /* If this type is created before sizetype has been permanently set, |
1812 | record it so set_sizetype can fix it up. */ | |
1813 | if (! sizetype_set) | |
ad41cc2a | 1814 | early_type_list = tree_cons (NULL_TREE, type, early_type_list); |
dc5041ab JJ |
1815 | |
1816 | /* If an alias set has been set for this aggregate when it was incomplete, | |
1817 | force it into alias set 0. | |
1818 | This is too conservative, but we cannot call record_component_aliases | |
1819 | here because some frontends still change the aggregates after | |
1820 | layout_type. */ | |
1821 | if (AGGREGATE_TYPE_P (type) && TYPE_ALIAS_SET_KNOWN_P (type)) | |
1822 | TYPE_ALIAS_SET (type) = 0; | |
7306ed3f JW |
1823 | } |
1824 | \f | |
1825 | /* Create and return a type for signed integers of PRECISION bits. */ | |
1826 | ||
1827 | tree | |
46c5ad27 | 1828 | make_signed_type (int precision) |
7306ed3f | 1829 | { |
b3694847 | 1830 | tree type = make_node (INTEGER_TYPE); |
7306ed3f JW |
1831 | |
1832 | TYPE_PRECISION (type) = precision; | |
1833 | ||
fed3cef0 | 1834 | fixup_signed_type (type); |
7306ed3f JW |
1835 | return type; |
1836 | } | |
1837 | ||
1838 | /* Create and return a type for unsigned integers of PRECISION bits. */ | |
1839 | ||
1840 | tree | |
46c5ad27 | 1841 | make_unsigned_type (int precision) |
7306ed3f | 1842 | { |
b3694847 | 1843 | tree type = make_node (INTEGER_TYPE); |
7306ed3f JW |
1844 | |
1845 | TYPE_PRECISION (type) = precision; | |
1846 | ||
7306ed3f JW |
1847 | fixup_unsigned_type (type); |
1848 | return type; | |
1849 | } | |
fed3cef0 RK |
1850 | \f |
1851 | /* Initialize sizetype and bitsizetype to a reasonable and temporary | |
1852 | value to enable integer types to be created. */ | |
1853 | ||
1854 | void | |
46c5ad27 | 1855 | initialize_sizetypes (void) |
fed3cef0 RK |
1856 | { |
1857 | tree t = make_node (INTEGER_TYPE); | |
1858 | ||
1859 | /* Set this so we do something reasonable for the build_int_2 calls | |
1860 | below. */ | |
1861 | integer_type_node = t; | |
1862 | ||
1863 | TYPE_MODE (t) = SImode; | |
1864 | TYPE_ALIGN (t) = GET_MODE_ALIGNMENT (SImode); | |
11cf4d18 | 1865 | TYPE_USER_ALIGN (t) = 0; |
fed3cef0 RK |
1866 | TYPE_SIZE (t) = build_int_2 (GET_MODE_BITSIZE (SImode), 0); |
1867 | TYPE_SIZE_UNIT (t) = build_int_2 (GET_MODE_SIZE (SImode), 0); | |
1868 | TREE_UNSIGNED (t) = 1; | |
1869 | TYPE_PRECISION (t) = GET_MODE_BITSIZE (SImode); | |
1870 | TYPE_MIN_VALUE (t) = build_int_2 (0, 0); | |
770ae6cc | 1871 | TYPE_IS_SIZETYPE (t) = 1; |
fed3cef0 RK |
1872 | |
1873 | /* 1000 avoids problems with possible overflow and is certainly | |
1874 | larger than any size value we'd want to be storing. */ | |
1875 | TYPE_MAX_VALUE (t) = build_int_2 (1000, 0); | |
1876 | ||
1877 | /* These two must be different nodes because of the caching done in | |
1878 | size_int_wide. */ | |
1879 | sizetype = t; | |
1880 | bitsizetype = copy_node (t); | |
1881 | integer_type_node = 0; | |
1882 | } | |
7306ed3f | 1883 | |
896cced4 | 1884 | /* Set sizetype to TYPE, and initialize *sizetype accordingly. |
f8dac6eb R |
1885 | Also update the type of any standard type's sizes made so far. */ |
1886 | ||
1887 | void | |
46c5ad27 | 1888 | set_sizetype (tree type) |
f8dac6eb | 1889 | { |
d4b60170 | 1890 | int oprecision = TYPE_PRECISION (type); |
f8dac6eb | 1891 | /* The *bitsizetype types use a precision that avoids overflows when |
d4b60170 RK |
1892 | calculating signed sizes / offsets in bits. However, when |
1893 | cross-compiling from a 32 bit to a 64 bit host, we are limited to 64 bit | |
1894 | precision. */ | |
11a6092b | 1895 | int precision = MIN (oprecision + BITS_PER_UNIT_LOG + 1, |
d4b60170 | 1896 | 2 * HOST_BITS_PER_WIDE_INT); |
fed3cef0 | 1897 | unsigned int i; |
ad41cc2a | 1898 | tree t; |
fed3cef0 RK |
1899 | |
1900 | if (sizetype_set) | |
1901 | abort (); | |
81b3411c | 1902 | |
fed3cef0 RK |
1903 | /* Make copies of nodes since we'll be setting TYPE_IS_SIZETYPE. */ |
1904 | sizetype = copy_node (type); | |
21318741 | 1905 | TYPE_DOMAIN (sizetype) = type; |
770ae6cc | 1906 | TYPE_IS_SIZETYPE (sizetype) = 1; |
81b3411c BS |
1907 | bitsizetype = make_node (INTEGER_TYPE); |
1908 | TYPE_NAME (bitsizetype) = TYPE_NAME (type); | |
f8dac6eb | 1909 | TYPE_PRECISION (bitsizetype) = precision; |
770ae6cc | 1910 | TYPE_IS_SIZETYPE (bitsizetype) = 1; |
d4b60170 | 1911 | |
896cced4 RH |
1912 | if (TREE_UNSIGNED (type)) |
1913 | fixup_unsigned_type (bitsizetype); | |
1914 | else | |
1915 | fixup_signed_type (bitsizetype); | |
d4b60170 | 1916 | |
f8dac6eb R |
1917 | layout_type (bitsizetype); |
1918 | ||
896cced4 RH |
1919 | if (TREE_UNSIGNED (type)) |
1920 | { | |
1921 | usizetype = sizetype; | |
1922 | ubitsizetype = bitsizetype; | |
fed3cef0 RK |
1923 | ssizetype = copy_node (make_signed_type (oprecision)); |
1924 | sbitsizetype = copy_node (make_signed_type (precision)); | |
896cced4 RH |
1925 | } |
1926 | else | |
1927 | { | |
1928 | ssizetype = sizetype; | |
1929 | sbitsizetype = bitsizetype; | |
fed3cef0 RK |
1930 | usizetype = copy_node (make_unsigned_type (oprecision)); |
1931 | ubitsizetype = copy_node (make_unsigned_type (precision)); | |
896cced4 | 1932 | } |
fed3cef0 RK |
1933 | |
1934 | TYPE_NAME (bitsizetype) = get_identifier ("bit_size_type"); | |
1935 | ||
21318741 | 1936 | /* Show is a sizetype, is a main type, and has no pointers to it. */ |
b6a1cbae | 1937 | for (i = 0; i < ARRAY_SIZE (sizetype_tab); i++) |
21318741 RK |
1938 | { |
1939 | TYPE_IS_SIZETYPE (sizetype_tab[i]) = 1; | |
1940 | TYPE_MAIN_VARIANT (sizetype_tab[i]) = sizetype_tab[i]; | |
1941 | TYPE_NEXT_VARIANT (sizetype_tab[i]) = 0; | |
1942 | TYPE_POINTER_TO (sizetype_tab[i]) = 0; | |
1943 | TYPE_REFERENCE_TO (sizetype_tab[i]) = 0; | |
1944 | } | |
d7db6646 | 1945 | |
fed3cef0 RK |
1946 | /* Go down each of the types we already made and set the proper type |
1947 | for the sizes in them. */ | |
ad41cc2a | 1948 | for (t = early_type_list; t != 0; t = TREE_CHAIN (t)) |
fed3cef0 | 1949 | { |
de7df9eb JM |
1950 | if (TREE_CODE (TREE_VALUE (t)) != INTEGER_TYPE |
1951 | && TREE_CODE (TREE_VALUE (t)) != BOOLEAN_TYPE) | |
fed3cef0 RK |
1952 | abort (); |
1953 | ||
ad41cc2a RK |
1954 | TREE_TYPE (TYPE_SIZE (TREE_VALUE (t))) = bitsizetype; |
1955 | TREE_TYPE (TYPE_SIZE_UNIT (TREE_VALUE (t))) = sizetype; | |
fed3cef0 RK |
1956 | } |
1957 | ||
1958 | early_type_list = 0; | |
1959 | sizetype_set = 1; | |
1960 | } | |
1961 | \f | |
7b6d72fc MM |
1962 | /* TYPE is an integral type, i.e., an INTEGRAL_TYPE, ENUMERAL_TYPE, |
1963 | BOOLEAN_TYPE, or CHAR_TYPE. Set TYPE_MIN_VALUE and TYPE_MAX_VALUE | |
1964 | for TYPE, based on the PRECISION and whether or not the TYPE | |
1965 | IS_UNSIGNED. PRECISION need not correspond to a width supported | |
1966 | natively by the hardware; for example, on a machine with 8-bit, | |
1967 | 16-bit, and 32-bit register modes, PRECISION might be 7, 23, or | |
1968 | 61. */ | |
1969 | ||
1970 | void | |
1971 | set_min_and_max_values_for_integral_type (tree type, | |
1972 | int precision, | |
1973 | bool is_unsigned) | |
1974 | { | |
1975 | tree min_value; | |
1976 | tree max_value; | |
1977 | ||
1978 | if (is_unsigned) | |
1979 | { | |
1980 | min_value = build_int_2 (0, 0); | |
1981 | max_value | |
1982 | = build_int_2 (precision - HOST_BITS_PER_WIDE_INT >= 0 | |
1983 | ? -1 : ((HOST_WIDE_INT) 1 << precision) - 1, | |
1984 | precision - HOST_BITS_PER_WIDE_INT > 0 | |
1985 | ? ((unsigned HOST_WIDE_INT) ~0 | |
1986 | >> (HOST_BITS_PER_WIDE_INT | |
1987 | - (precision - HOST_BITS_PER_WIDE_INT))) | |
1988 | : 0); | |
1989 | } | |
1990 | else | |
1991 | { | |
1992 | min_value | |
1993 | = build_int_2 ((precision - HOST_BITS_PER_WIDE_INT > 0 | |
1994 | ? 0 : (HOST_WIDE_INT) (-1) << (precision - 1)), | |
1995 | (((HOST_WIDE_INT) (-1) | |
1996 | << (precision - HOST_BITS_PER_WIDE_INT - 1 > 0 | |
1997 | ? precision - HOST_BITS_PER_WIDE_INT - 1 | |
1998 | : 0)))); | |
1999 | max_value | |
2000 | = build_int_2 ((precision - HOST_BITS_PER_WIDE_INT > 0 | |
2001 | ? -1 : ((HOST_WIDE_INT) 1 << (precision - 1)) - 1), | |
2002 | (precision - HOST_BITS_PER_WIDE_INT - 1 > 0 | |
2003 | ? (((HOST_WIDE_INT) 1 | |
2004 | << (precision - HOST_BITS_PER_WIDE_INT - 1))) - 1 | |
2005 | : 0)); | |
2006 | } | |
2007 | ||
2008 | TREE_TYPE (min_value) = type; | |
2009 | TREE_TYPE (max_value) = type; | |
2010 | TYPE_MIN_VALUE (type) = min_value; | |
2011 | TYPE_MAX_VALUE (type) = max_value; | |
2012 | } | |
2013 | ||
4cc89e53 | 2014 | /* Set the extreme values of TYPE based on its precision in bits, |
13756074 | 2015 | then lay it out. Used when make_signed_type won't do |
4cc89e53 RS |
2016 | because the tree code is not INTEGER_TYPE. |
2017 | E.g. for Pascal, when the -fsigned-char option is given. */ | |
2018 | ||
2019 | void | |
46c5ad27 | 2020 | fixup_signed_type (tree type) |
4cc89e53 | 2021 | { |
b3694847 | 2022 | int precision = TYPE_PRECISION (type); |
4cc89e53 | 2023 | |
9cd56be1 JH |
2024 | /* We can not represent properly constants greater then |
2025 | 2 * HOST_BITS_PER_WIDE_INT, still we need the types | |
2026 | as they are used by i386 vector extensions and friends. */ | |
2027 | if (precision > HOST_BITS_PER_WIDE_INT * 2) | |
2028 | precision = HOST_BITS_PER_WIDE_INT * 2; | |
2029 | ||
7b6d72fc MM |
2030 | set_min_and_max_values_for_integral_type (type, precision, |
2031 | /*is_unsigned=*/false); | |
4cc89e53 RS |
2032 | |
2033 | /* Lay out the type: set its alignment, size, etc. */ | |
4cc89e53 RS |
2034 | layout_type (type); |
2035 | } | |
2036 | ||
7306ed3f | 2037 | /* Set the extreme values of TYPE based on its precision in bits, |
13756074 | 2038 | then lay it out. This is used both in `make_unsigned_type' |
7306ed3f JW |
2039 | and for enumeral types. */ |
2040 | ||
2041 | void | |
46c5ad27 | 2042 | fixup_unsigned_type (tree type) |
7306ed3f | 2043 | { |
b3694847 | 2044 | int precision = TYPE_PRECISION (type); |
7306ed3f | 2045 | |
9cd56be1 JH |
2046 | /* We can not represent properly constants greater then |
2047 | 2 * HOST_BITS_PER_WIDE_INT, still we need the types | |
2048 | as they are used by i386 vector extensions and friends. */ | |
2049 | if (precision > HOST_BITS_PER_WIDE_INT * 2) | |
2050 | precision = HOST_BITS_PER_WIDE_INT * 2; | |
2051 | ||
7b6d72fc MM |
2052 | set_min_and_max_values_for_integral_type (type, precision, |
2053 | /*is_unsigned=*/true); | |
7306ed3f JW |
2054 | |
2055 | /* Lay out the type: set its alignment, size, etc. */ | |
7306ed3f JW |
2056 | layout_type (type); |
2057 | } | |
2058 | \f | |
2059 | /* Find the best machine mode to use when referencing a bit field of length | |
2060 | BITSIZE bits starting at BITPOS. | |
2061 | ||
2062 | The underlying object is known to be aligned to a boundary of ALIGN bits. | |
2063 | If LARGEST_MODE is not VOIDmode, it means that we should not use a mode | |
2064 | larger than LARGEST_MODE (usually SImode). | |
2065 | ||
2066 | If no mode meets all these conditions, we return VOIDmode. Otherwise, if | |
2067 | VOLATILEP is true or SLOW_BYTE_ACCESS is false, we return the smallest | |
2068 | mode meeting these conditions. | |
2069 | ||
77fa0940 RK |
2070 | Otherwise (VOLATILEP is false and SLOW_BYTE_ACCESS is true), we return |
2071 | the largest mode (but a mode no wider than UNITS_PER_WORD) that meets | |
2072 | all the conditions. */ | |
7306ed3f JW |
2073 | |
2074 | enum machine_mode | |
46c5ad27 AJ |
2075 | get_best_mode (int bitsize, int bitpos, unsigned int align, |
2076 | enum machine_mode largest_mode, int volatilep) | |
7306ed3f JW |
2077 | { |
2078 | enum machine_mode mode; | |
770ae6cc | 2079 | unsigned int unit = 0; |
7306ed3f JW |
2080 | |
2081 | /* Find the narrowest integer mode that contains the bit field. */ | |
2082 | for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode; | |
2083 | mode = GET_MODE_WIDER_MODE (mode)) | |
2084 | { | |
2085 | unit = GET_MODE_BITSIZE (mode); | |
956d6950 | 2086 | if ((bitpos % unit) + bitsize <= unit) |
7306ed3f JW |
2087 | break; |
2088 | } | |
2089 | ||
0c61f541 | 2090 | if (mode == VOIDmode |
7306ed3f | 2091 | /* It is tempting to omit the following line |
4e4b555d | 2092 | if STRICT_ALIGNMENT is true. |
7306ed3f JW |
2093 | But that is incorrect, since if the bitfield uses part of 3 bytes |
2094 | and we use a 4-byte mode, we could get a spurious segv | |
2095 | if the extra 4th byte is past the end of memory. | |
2096 | (Though at least one Unix compiler ignores this problem: | |
2097 | that on the Sequent 386 machine. */ | |
770ae6cc | 2098 | || MIN (unit, BIGGEST_ALIGNMENT) > align |
7306ed3f JW |
2099 | || (largest_mode != VOIDmode && unit > GET_MODE_BITSIZE (largest_mode))) |
2100 | return VOIDmode; | |
2101 | ||
77fa0940 RK |
2102 | if (SLOW_BYTE_ACCESS && ! volatilep) |
2103 | { | |
2104 | enum machine_mode wide_mode = VOIDmode, tmode; | |
2105 | ||
2106 | for (tmode = GET_CLASS_NARROWEST_MODE (MODE_INT); tmode != VOIDmode; | |
2107 | tmode = GET_MODE_WIDER_MODE (tmode)) | |
2108 | { | |
2109 | unit = GET_MODE_BITSIZE (tmode); | |
2110 | if (bitpos / unit == (bitpos + bitsize - 1) / unit | |
2111 | && unit <= BITS_PER_WORD | |
770ae6cc | 2112 | && unit <= MIN (align, BIGGEST_ALIGNMENT) |
77fa0940 RK |
2113 | && (largest_mode == VOIDmode |
2114 | || unit <= GET_MODE_BITSIZE (largest_mode))) | |
2115 | wide_mode = tmode; | |
2116 | } | |
2117 | ||
2118 | if (wide_mode != VOIDmode) | |
2119 | return wide_mode; | |
2120 | } | |
7306ed3f JW |
2121 | |
2122 | return mode; | |
2123 | } | |
d7db6646 | 2124 | |
e2500fed | 2125 | #include "gt-stor-layout.h" |