]>
Commit | Line | Data |
---|---|---|
7306ed3f | 1 | /* C-compiler utilities for types and variables storage layout |
06ceef4e | 2 | Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1996, 1998, |
25d8d27d | 3 | 1999, 2000, 2001, 2002, 2003, 2004, 2005 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" |
26277d41 | 37 | #include "regs.h" |
89b0433e | 38 | #include "params.h" |
7306ed3f | 39 | |
7306ed3f | 40 | /* Data type for the expressions representing sizes of data types. |
896cced4 | 41 | It is the first integer type laid out. */ |
fed3cef0 | 42 | tree sizetype_tab[(int) TYPE_KIND_LAST]; |
7306ed3f | 43 | |
d4c40650 RS |
44 | /* If nonzero, this is an upper limit on alignment of structure fields. |
45 | The value is measured in bits. */ | |
467cecf3 | 46 | unsigned int maximum_field_alignment = TARGET_DEFAULT_PACK_STRUCT * BITS_PER_UNIT; |
8c27b7d4 | 47 | /* ... and its original value in bytes, specified via -fpack-struct=<value>. */ |
467cecf3 | 48 | unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT; |
d4c40650 | 49 | |
b5d6a2ff RK |
50 | /* Nonzero if all REFERENCE_TYPEs are internal and hence should be |
51 | allocated in Pmode, not ptr_mode. Set only by internal_reference_types | |
52 | called only by a front end. */ | |
53 | static int reference_types_internal = 0; | |
54 | ||
46c5ad27 AJ |
55 | static void finalize_record_size (record_layout_info); |
56 | static void finalize_type_size (tree); | |
57 | static void place_union_field (record_layout_info, tree); | |
b8089d8d | 58 | #if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED) |
46c5ad27 AJ |
59 | static int excess_unit_span (HOST_WIDE_INT, HOST_WIDE_INT, HOST_WIDE_INT, |
60 | HOST_WIDE_INT, tree); | |
b8089d8d | 61 | #endif |
46c5ad27 | 62 | extern void debug_rli (record_layout_info); |
7306ed3f JW |
63 | \f |
64 | /* SAVE_EXPRs for sizes of types and decls, waiting to be expanded. */ | |
65 | ||
e2500fed | 66 | static GTY(()) tree pending_sizes; |
7306ed3f | 67 | |
b5d6a2ff RK |
68 | /* Show that REFERENCE_TYPES are internal and should be Pmode. Called only |
69 | by front end. */ | |
70 | ||
71 | void | |
46c5ad27 | 72 | internal_reference_types (void) |
b5d6a2ff RK |
73 | { |
74 | reference_types_internal = 1; | |
75 | } | |
76 | ||
770ae6cc RK |
77 | /* Get a list of all the objects put on the pending sizes list. */ |
78 | ||
7306ed3f | 79 | tree |
46c5ad27 | 80 | get_pending_sizes (void) |
7306ed3f JW |
81 | { |
82 | tree chain = pending_sizes; | |
d4b60170 | 83 | |
7306ed3f JW |
84 | pending_sizes = 0; |
85 | return chain; | |
86 | } | |
87 | ||
fe375cf1 JJ |
88 | /* Add EXPR to the pending sizes list. */ |
89 | ||
90 | void | |
46c5ad27 | 91 | put_pending_size (tree expr) |
fe375cf1 | 92 | { |
3874585e RK |
93 | /* Strip any simple arithmetic from EXPR to see if it has an underlying |
94 | SAVE_EXPR. */ | |
a9ecacf6 | 95 | expr = skip_simple_arithmetic (expr); |
3874585e RK |
96 | |
97 | if (TREE_CODE (expr) == SAVE_EXPR) | |
98 | pending_sizes = tree_cons (NULL_TREE, expr, pending_sizes); | |
fe375cf1 JJ |
99 | } |
100 | ||
770ae6cc RK |
101 | /* Put a chain of objects into the pending sizes list, which must be |
102 | empty. */ | |
103 | ||
1fd7c4ac | 104 | void |
46c5ad27 | 105 | put_pending_sizes (tree chain) |
1fd7c4ac | 106 | { |
41374e13 | 107 | gcc_assert (!pending_sizes); |
1fd7c4ac RK |
108 | pending_sizes = chain; |
109 | } | |
110 | ||
76ffb3a0 | 111 | /* Given a size SIZE that may not be a constant, return a SAVE_EXPR |
7306ed3f JW |
112 | to serve as the actual size-expression for a type or decl. */ |
113 | ||
4e4b555d | 114 | tree |
46c5ad27 | 115 | variable_size (tree size) |
7306ed3f | 116 | { |
3695c25f JM |
117 | tree save; |
118 | ||
5e9bec99 RK |
119 | /* If the language-processor is to take responsibility for variable-sized |
120 | items (e.g., languages which have elaboration procedures like Ada), | |
ac79cd5a RK |
121 | just return SIZE unchanged. Likewise for self-referential sizes and |
122 | constant sizes. */ | |
76ffb3a0 | 123 | if (TREE_CONSTANT (size) |
ae2bcd98 | 124 | || lang_hooks.decls.global_bindings_p () < 0 |
679035f3 | 125 | || CONTAINS_PLACEHOLDER_P (size)) |
5e9bec99 RK |
126 | return size; |
127 | ||
ad50bc8d | 128 | size = save_expr (size); |
68de3831 | 129 | |
d26f8097 MM |
130 | /* If an array with a variable number of elements is declared, and |
131 | the elements require destruction, we will emit a cleanup for the | |
132 | array. That cleanup is run both on normal exit from the block | |
133 | and in the exception-handler for the block. Normally, when code | |
134 | is used in both ordinary code and in an exception handler it is | |
135 | `unsaved', i.e., all SAVE_EXPRs are recalculated. However, we do | |
136 | not wish to do that here; the array-size is the same in both | |
137 | places. */ | |
1c9766da | 138 | save = skip_simple_arithmetic (size); |
d26f8097 | 139 | |
6a0bec2c | 140 | if (cfun && cfun->x_dont_save_pending_sizes_p) |
6de9cd9a DN |
141 | /* The front-end doesn't want us to keep a list of the expressions |
142 | that determine sizes for variable size objects. Trust it. */ | |
143 | return size; | |
144 | ||
ae2bcd98 | 145 | if (lang_hooks.decls.global_bindings_p ()) |
7306ed3f | 146 | { |
80f9c711 | 147 | if (TREE_CONSTANT (size)) |
971801ff | 148 | error ("type size can%'t be explicitly evaluated"); |
80f9c711 RS |
149 | else |
150 | error ("variable-size type declared outside of any function"); | |
151 | ||
fed3cef0 | 152 | return size_one_node; |
7306ed3f JW |
153 | } |
154 | ||
6a0bec2c | 155 | put_pending_size (save); |
7306ed3f JW |
156 | |
157 | return size; | |
158 | } | |
159 | \f | |
160 | #ifndef MAX_FIXED_MODE_SIZE | |
161 | #define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (DImode) | |
162 | #endif | |
163 | ||
37783865 ZW |
164 | /* Return the machine mode to use for a nonscalar of SIZE bits. The |
165 | mode must be in class CLASS, and have exactly that many value bits; | |
166 | it may have padding as well. If LIMIT is nonzero, modes of wider | |
167 | than MAX_FIXED_MODE_SIZE will not be used. */ | |
7306ed3f JW |
168 | |
169 | enum machine_mode | |
46c5ad27 | 170 | mode_for_size (unsigned int size, enum mode_class class, int limit) |
7306ed3f | 171 | { |
b3694847 | 172 | enum machine_mode mode; |
7306ed3f | 173 | |
72c602fc | 174 | if (limit && size > MAX_FIXED_MODE_SIZE) |
7306ed3f JW |
175 | return BLKmode; |
176 | ||
5e9bec99 | 177 | /* Get the first mode which has this size, in the specified class. */ |
7306ed3f JW |
178 | for (mode = GET_CLASS_NARROWEST_MODE (class); mode != VOIDmode; |
179 | mode = GET_MODE_WIDER_MODE (mode)) | |
37783865 | 180 | if (GET_MODE_PRECISION (mode) == size) |
7306ed3f JW |
181 | return mode; |
182 | ||
183 | return BLKmode; | |
184 | } | |
185 | ||
72c602fc RK |
186 | /* Similar, except passed a tree node. */ |
187 | ||
188 | enum machine_mode | |
46c5ad27 | 189 | mode_for_size_tree (tree size, enum mode_class class, int limit) |
72c602fc RK |
190 | { |
191 | if (TREE_CODE (size) != INTEGER_CST | |
5826955d | 192 | || TREE_OVERFLOW (size) |
72c602fc RK |
193 | /* What we really want to say here is that the size can fit in a |
194 | host integer, but we know there's no way we'd find a mode for | |
195 | this many bits, so there's no point in doing the precise test. */ | |
05bccae2 | 196 | || compare_tree_int (size, 1000) > 0) |
72c602fc RK |
197 | return BLKmode; |
198 | else | |
0384674e | 199 | return mode_for_size (tree_low_cst (size, 1), class, limit); |
72c602fc RK |
200 | } |
201 | ||
5e9bec99 | 202 | /* Similar, but never return BLKmode; return the narrowest mode that |
37783865 | 203 | contains at least the requested number of value bits. */ |
5e9bec99 | 204 | |
27922c13 | 205 | enum machine_mode |
46c5ad27 | 206 | smallest_mode_for_size (unsigned int size, enum mode_class class) |
5e9bec99 | 207 | { |
b3694847 | 208 | enum machine_mode mode; |
5e9bec99 RK |
209 | |
210 | /* Get the first mode which has at least this size, in the | |
211 | specified class. */ | |
212 | for (mode = GET_CLASS_NARROWEST_MODE (class); mode != VOIDmode; | |
213 | mode = GET_MODE_WIDER_MODE (mode)) | |
37783865 | 214 | if (GET_MODE_PRECISION (mode) >= size) |
5e9bec99 RK |
215 | return mode; |
216 | ||
41374e13 | 217 | gcc_unreachable (); |
5e9bec99 RK |
218 | } |
219 | ||
d006aa54 RH |
220 | /* Find an integer mode of the exact same size, or BLKmode on failure. */ |
221 | ||
222 | enum machine_mode | |
46c5ad27 | 223 | int_mode_for_mode (enum machine_mode mode) |
d006aa54 RH |
224 | { |
225 | switch (GET_MODE_CLASS (mode)) | |
226 | { | |
227 | case MODE_INT: | |
228 | case MODE_PARTIAL_INT: | |
229 | break; | |
230 | ||
231 | case MODE_COMPLEX_INT: | |
232 | case MODE_COMPLEX_FLOAT: | |
233 | case MODE_FLOAT: | |
62c07905 JM |
234 | case MODE_VECTOR_INT: |
235 | case MODE_VECTOR_FLOAT: | |
d006aa54 RH |
236 | mode = mode_for_size (GET_MODE_BITSIZE (mode), MODE_INT, 0); |
237 | break; | |
238 | ||
239 | case MODE_RANDOM: | |
240 | if (mode == BLKmode) | |
786de7eb | 241 | break; |
d4b60170 | 242 | |
2d76cb1a | 243 | /* ... fall through ... */ |
d006aa54 RH |
244 | |
245 | case MODE_CC: | |
246 | default: | |
41374e13 | 247 | gcc_unreachable (); |
d006aa54 RH |
248 | } |
249 | ||
250 | return mode; | |
251 | } | |
252 | ||
187515f5 AO |
253 | /* Return the alignment of MODE. This will be bounded by 1 and |
254 | BIGGEST_ALIGNMENT. */ | |
255 | ||
256 | unsigned int | |
46c5ad27 | 257 | get_mode_alignment (enum machine_mode mode) |
187515f5 | 258 | { |
0974c7d7 | 259 | return MIN (BIGGEST_ALIGNMENT, MAX (1, mode_base_align[mode]*BITS_PER_UNIT)); |
187515f5 AO |
260 | } |
261 | ||
7306ed3f | 262 | \f |
78d55cc8 JM |
263 | /* Subroutine of layout_decl: Force alignment required for the data type. |
264 | But if the decl itself wants greater alignment, don't override that. */ | |
265 | ||
266 | static inline void | |
267 | do_type_align (tree type, tree decl) | |
268 | { | |
269 | if (TYPE_ALIGN (type) > DECL_ALIGN (decl)) | |
270 | { | |
271 | DECL_ALIGN (decl) = TYPE_ALIGN (type); | |
3acef2ae JM |
272 | if (TREE_CODE (decl) == FIELD_DECL) |
273 | DECL_USER_ALIGN (decl) = TYPE_USER_ALIGN (type); | |
78d55cc8 JM |
274 | } |
275 | } | |
276 | ||
7306ed3f JW |
277 | /* Set the size, mode and alignment of a ..._DECL node. |
278 | TYPE_DECL does need this for C++. | |
279 | Note that LABEL_DECL and CONST_DECL nodes do not need this, | |
280 | and FUNCTION_DECL nodes have them set up in a special (and simple) way. | |
281 | Don't call layout_decl for them. | |
282 | ||
283 | KNOWN_ALIGN is the amount of alignment we can assume this | |
284 | decl has with no special effort. It is relevant only for FIELD_DECLs | |
285 | and depends on the previous fields. | |
286 | All that matters about KNOWN_ALIGN is which powers of 2 divide it. | |
287 | If KNOWN_ALIGN is 0, it means, "as much alignment as you like": | |
288 | the record will be aligned to suit. */ | |
289 | ||
290 | void | |
46c5ad27 | 291 | layout_decl (tree decl, unsigned int known_align) |
7306ed3f | 292 | { |
b3694847 SS |
293 | tree type = TREE_TYPE (decl); |
294 | enum tree_code code = TREE_CODE (decl); | |
a46666a9 | 295 | rtx rtl = NULL_RTX; |
7306ed3f JW |
296 | |
297 | if (code == CONST_DECL) | |
298 | return; | |
41374e13 NS |
299 | |
300 | gcc_assert (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL | |
301 | || code == TYPE_DECL ||code == FIELD_DECL); | |
302 | ||
a46666a9 RH |
303 | rtl = DECL_RTL_IF_SET (decl); |
304 | ||
7306ed3f | 305 | if (type == error_mark_node) |
33433751 | 306 | type = void_type_node; |
7306ed3f | 307 | |
770ae6cc RK |
308 | /* Usually the size and mode come from the data type without change, |
309 | however, the front-end may set the explicit width of the field, so its | |
310 | size may not be the same as the size of its type. This happens with | |
311 | bitfields, of course (an `int' bitfield may be only 2 bits, say), but it | |
312 | also happens with other fields. For example, the C++ front-end creates | |
313 | zero-sized fields corresponding to empty base classes, and depends on | |
314 | layout_type setting DECL_FIELD_BITPOS correctly for the field. Set the | |
4b6bf620 RK |
315 | size in bytes from the size in bits. If we have already set the mode, |
316 | don't set it again since we can be called twice for FIELD_DECLs. */ | |
770ae6cc | 317 | |
a150de29 | 318 | DECL_UNSIGNED (decl) = TYPE_UNSIGNED (type); |
4b6bf620 RK |
319 | if (DECL_MODE (decl) == VOIDmode) |
320 | DECL_MODE (decl) = TYPE_MODE (type); | |
770ae6cc | 321 | |
5e9bec99 | 322 | if (DECL_SIZE (decl) == 0) |
06ceef4e | 323 | { |
ad50bc8d RH |
324 | DECL_SIZE (decl) = TYPE_SIZE (type); |
325 | DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (type); | |
06ceef4e | 326 | } |
1a96dc46 | 327 | else if (DECL_SIZE_UNIT (decl) == 0) |
770ae6cc | 328 | DECL_SIZE_UNIT (decl) |
455f19cb MM |
329 | = fold_convert (sizetype, size_binop (CEIL_DIV_EXPR, DECL_SIZE (decl), |
330 | bitsize_unit_node)); | |
06ceef4e | 331 | |
78d55cc8 JM |
332 | if (code != FIELD_DECL) |
333 | /* For non-fields, update the alignment from the type. */ | |
334 | do_type_align (type, decl); | |
335 | else | |
336 | /* For fields, it's a bit more complicated... */ | |
786de7eb | 337 | { |
40aae178 JM |
338 | bool old_user_align = DECL_USER_ALIGN (decl); |
339 | ||
78d55cc8 JM |
340 | if (DECL_BIT_FIELD (decl)) |
341 | { | |
342 | DECL_BIT_FIELD_TYPE (decl) = type; | |
7306ed3f | 343 | |
78d55cc8 JM |
344 | /* A zero-length bit-field affects the alignment of the next |
345 | field. */ | |
346 | if (integer_zerop (DECL_SIZE (decl)) | |
347 | && ! DECL_PACKED (decl) | |
5fd9b178 | 348 | && ! targetm.ms_bitfield_layout_p (DECL_FIELD_CONTEXT (decl))) |
78d55cc8 JM |
349 | { |
350 | #ifdef PCC_BITFIELD_TYPE_MATTERS | |
351 | if (PCC_BITFIELD_TYPE_MATTERS) | |
352 | do_type_align (type, decl); | |
353 | else | |
354 | #endif | |
ad3f5759 | 355 | { |
78d55cc8 | 356 | #ifdef EMPTY_FIELD_BOUNDARY |
ad3f5759 AS |
357 | if (EMPTY_FIELD_BOUNDARY > DECL_ALIGN (decl)) |
358 | { | |
359 | DECL_ALIGN (decl) = EMPTY_FIELD_BOUNDARY; | |
360 | DECL_USER_ALIGN (decl) = 0; | |
361 | } | |
78d55cc8 | 362 | #endif |
ad3f5759 | 363 | } |
78d55cc8 JM |
364 | } |
365 | ||
366 | /* See if we can use an ordinary integer mode for a bit-field. | |
367 | Conditions are: a fixed size that is correct for another mode | |
368 | and occupying a complete byte or bytes on proper boundary. */ | |
369 | if (TYPE_SIZE (type) != 0 | |
370 | && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST | |
371 | && GET_MODE_CLASS (TYPE_MODE (type)) == MODE_INT) | |
372 | { | |
373 | enum machine_mode xmode | |
374 | = mode_for_size_tree (DECL_SIZE (decl), MODE_INT, 1); | |
375 | ||
f676971a | 376 | if (xmode != BLKmode |
9a706ec7 MM |
377 | && (known_align == 0 |
378 | || known_align >= GET_MODE_ALIGNMENT (xmode))) | |
78d55cc8 JM |
379 | { |
380 | DECL_ALIGN (decl) = MAX (GET_MODE_ALIGNMENT (xmode), | |
381 | DECL_ALIGN (decl)); | |
382 | DECL_MODE (decl) = xmode; | |
383 | DECL_BIT_FIELD (decl) = 0; | |
384 | } | |
385 | } | |
386 | ||
387 | /* Turn off DECL_BIT_FIELD if we won't need it set. */ | |
388 | if (TYPE_MODE (type) == BLKmode && DECL_MODE (decl) == BLKmode | |
389 | && known_align >= TYPE_ALIGN (type) | |
390 | && DECL_ALIGN (decl) >= TYPE_ALIGN (type)) | |
391 | DECL_BIT_FIELD (decl) = 0; | |
392 | } | |
393 | else if (DECL_PACKED (decl) && DECL_USER_ALIGN (decl)) | |
394 | /* Don't touch DECL_ALIGN. For other packed fields, go ahead and | |
2038bd69 | 395 | round up; we'll reduce it again below. We want packing to |
ba228239 | 396 | supersede USER_ALIGN inherited from the type, but defer to |
2038bd69 | 397 | alignment explicitly specified on the field decl. */; |
78d55cc8 | 398 | else |
40aae178 JM |
399 | do_type_align (type, decl); |
400 | ||
401 | /* If the field is of variable size, we can't misalign it since we | |
402 | have no way to make a temporary to align the result. But this | |
403 | isn't an issue if the decl is not addressable. Likewise if it | |
404 | is of unknown size. | |
405 | ||
406 | Note that do_type_align may set DECL_USER_ALIGN, so we need to | |
407 | check old_user_align instead. */ | |
408 | if (DECL_PACKED (decl) | |
409 | && !old_user_align | |
410 | && (DECL_NONADDRESSABLE_P (decl) | |
411 | || DECL_SIZE_UNIT (decl) == 0 | |
412 | || TREE_CODE (DECL_SIZE_UNIT (decl)) == INTEGER_CST)) | |
413 | DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), BITS_PER_UNIT); | |
78d55cc8 | 414 | |
9ca75f15 | 415 | if (! DECL_USER_ALIGN (decl) && ! DECL_PACKED (decl)) |
7306ed3f | 416 | { |
78d55cc8 JM |
417 | /* Some targets (i.e. i386, VMS) limit struct field alignment |
418 | to a lower boundary than alignment of variables unless | |
419 | it was overridden by attribute aligned. */ | |
420 | #ifdef BIGGEST_FIELD_ALIGNMENT | |
421 | DECL_ALIGN (decl) | |
422 | = MIN (DECL_ALIGN (decl), (unsigned) BIGGEST_FIELD_ALIGNMENT); | |
423 | #endif | |
424 | #ifdef ADJUST_FIELD_ALIGN | |
425 | DECL_ALIGN (decl) = ADJUST_FIELD_ALIGN (decl, DECL_ALIGN (decl)); | |
426 | #endif | |
7306ed3f | 427 | } |
9ca75f15 DJ |
428 | |
429 | /* Should this be controlled by DECL_USER_ALIGN, too? */ | |
430 | if (maximum_field_alignment != 0) | |
431 | DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), maximum_field_alignment); | |
7306ed3f JW |
432 | } |
433 | ||
434 | /* Evaluate nonconstant size only once, either now or as soon as safe. */ | |
435 | if (DECL_SIZE (decl) != 0 && TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST) | |
436 | DECL_SIZE (decl) = variable_size (DECL_SIZE (decl)); | |
06ceef4e RK |
437 | if (DECL_SIZE_UNIT (decl) != 0 |
438 | && TREE_CODE (DECL_SIZE_UNIT (decl)) != INTEGER_CST) | |
439 | DECL_SIZE_UNIT (decl) = variable_size (DECL_SIZE_UNIT (decl)); | |
440 | ||
441 | /* If requested, warn about definitions of large data objects. */ | |
442 | if (warn_larger_than | |
17aec3eb | 443 | && (code == VAR_DECL || code == PARM_DECL) |
06ceef4e RK |
444 | && ! DECL_EXTERNAL (decl)) |
445 | { | |
446 | tree size = DECL_SIZE_UNIT (decl); | |
447 | ||
448 | if (size != 0 && TREE_CODE (size) == INTEGER_CST | |
05bccae2 | 449 | && compare_tree_int (size, larger_than_size) > 0) |
06ceef4e | 450 | { |
0384674e | 451 | int size_as_int = TREE_INT_CST_LOW (size); |
06ceef4e | 452 | |
05bccae2 | 453 | if (compare_tree_int (size, size_as_int) == 0) |
d4ee4d25 | 454 | warning (0, "%Jsize of %qD is %d bytes", decl, decl, size_as_int); |
06ceef4e | 455 | else |
d4ee4d25 | 456 | warning (0, "%Jsize of %qD is larger than %d bytes", |
ddd2d57e | 457 | decl, decl, larger_than_size); |
06ceef4e RK |
458 | } |
459 | } | |
a46666a9 RH |
460 | |
461 | /* If the RTL was already set, update its mode and mem attributes. */ | |
462 | if (rtl) | |
463 | { | |
464 | PUT_MODE (rtl, DECL_MODE (decl)); | |
465 | SET_DECL_RTL (decl, 0); | |
466 | set_mem_attributes (rtl, decl, 1); | |
467 | SET_DECL_RTL (decl, rtl); | |
468 | } | |
7306ed3f | 469 | } |
d8472c75 JM |
470 | |
471 | /* Given a VAR_DECL, PARM_DECL or RESULT_DECL, clears the results of | |
472 | a previous call to layout_decl and calls it again. */ | |
473 | ||
474 | void | |
475 | relayout_decl (tree decl) | |
476 | { | |
477 | DECL_SIZE (decl) = DECL_SIZE_UNIT (decl) = 0; | |
478 | DECL_MODE (decl) = VOIDmode; | |
479 | DECL_ALIGN (decl) = 0; | |
480 | SET_DECL_RTL (decl, 0); | |
481 | ||
482 | layout_decl (decl, 0); | |
483 | } | |
7306ed3f | 484 | \f |
e0cea8d9 RK |
485 | /* Hook for a front-end function that can modify the record layout as needed |
486 | immediately before it is finalized. */ | |
487 | ||
1bb11558 | 488 | static void (*lang_adjust_rli) (record_layout_info) = 0; |
e0cea8d9 RK |
489 | |
490 | void | |
46c5ad27 | 491 | set_lang_adjust_rli (void (*f) (record_layout_info)) |
e0cea8d9 RK |
492 | { |
493 | lang_adjust_rli = f; | |
494 | } | |
495 | ||
770ae6cc RK |
496 | /* Begin laying out type T, which may be a RECORD_TYPE, UNION_TYPE, or |
497 | QUAL_UNION_TYPE. Return a pointer to a struct record_layout_info which | |
498 | is to be passed to all other layout functions for this record. It is the | |
786de7eb | 499 | responsibility of the caller to call `free' for the storage returned. |
770ae6cc RK |
500 | Note that garbage collection is not permitted until we finish laying |
501 | out the record. */ | |
7306ed3f | 502 | |
9328904c | 503 | record_layout_info |
46c5ad27 | 504 | start_record_layout (tree t) |
7306ed3f | 505 | { |
703ad42b | 506 | record_layout_info rli = xmalloc (sizeof (struct record_layout_info_s)); |
9328904c MM |
507 | |
508 | rli->t = t; | |
770ae6cc | 509 | |
9328904c MM |
510 | /* If the type has a minimum specified alignment (via an attribute |
511 | declaration, for example) use it -- otherwise, start with a | |
512 | one-byte alignment. */ | |
513 | rli->record_align = MAX (BITS_PER_UNIT, TYPE_ALIGN (t)); | |
78d55cc8 | 514 | rli->unpacked_align = rli->record_align; |
770ae6cc | 515 | rli->offset_align = MAX (rli->record_align, BIGGEST_ALIGNMENT); |
7306ed3f | 516 | |
5c19a356 MS |
517 | #ifdef STRUCTURE_SIZE_BOUNDARY |
518 | /* Packed structures don't need to have minimum size. */ | |
f132af85 | 519 | if (! TYPE_PACKED (t)) |
fc555370 | 520 | rli->record_align = MAX (rli->record_align, (unsigned) STRUCTURE_SIZE_BOUNDARY); |
5c19a356 | 521 | #endif |
7306ed3f | 522 | |
770ae6cc RK |
523 | rli->offset = size_zero_node; |
524 | rli->bitpos = bitsize_zero_node; | |
f913c102 | 525 | rli->prev_field = 0; |
770ae6cc RK |
526 | rli->pending_statics = 0; |
527 | rli->packed_maybe_necessary = 0; | |
528 | ||
9328904c MM |
529 | return rli; |
530 | } | |
7306ed3f | 531 | |
f2704b9f RK |
532 | /* These four routines perform computations that convert between |
533 | the offset/bitpos forms and byte and bit offsets. */ | |
534 | ||
535 | tree | |
46c5ad27 | 536 | bit_from_pos (tree offset, tree bitpos) |
f2704b9f RK |
537 | { |
538 | return size_binop (PLUS_EXPR, bitpos, | |
455f19cb MM |
539 | size_binop (MULT_EXPR, |
540 | fold_convert (bitsizetype, offset), | |
f2704b9f RK |
541 | bitsize_unit_node)); |
542 | } | |
543 | ||
544 | tree | |
46c5ad27 | 545 | byte_from_pos (tree offset, tree bitpos) |
f2704b9f RK |
546 | { |
547 | return size_binop (PLUS_EXPR, offset, | |
455f19cb MM |
548 | fold_convert (sizetype, |
549 | size_binop (TRUNC_DIV_EXPR, bitpos, | |
550 | bitsize_unit_node))); | |
f2704b9f RK |
551 | } |
552 | ||
f2704b9f | 553 | void |
46c5ad27 AJ |
554 | pos_from_bit (tree *poffset, tree *pbitpos, unsigned int off_align, |
555 | tree pos) | |
f2704b9f RK |
556 | { |
557 | *poffset = size_binop (MULT_EXPR, | |
455f19cb MM |
558 | fold_convert (sizetype, |
559 | size_binop (FLOOR_DIV_EXPR, pos, | |
560 | bitsize_int (off_align))), | |
f2704b9f RK |
561 | size_int (off_align / BITS_PER_UNIT)); |
562 | *pbitpos = size_binop (FLOOR_MOD_EXPR, pos, bitsize_int (off_align)); | |
563 | } | |
564 | ||
565 | /* Given a pointer to bit and byte offsets and an offset alignment, | |
566 | normalize the offsets so they are within the alignment. */ | |
567 | ||
568 | void | |
46c5ad27 | 569 | normalize_offset (tree *poffset, tree *pbitpos, unsigned int off_align) |
f2704b9f RK |
570 | { |
571 | /* If the bit position is now larger than it should be, adjust it | |
572 | downwards. */ | |
573 | if (compare_tree_int (*pbitpos, off_align) >= 0) | |
574 | { | |
575 | tree extra_aligns = size_binop (FLOOR_DIV_EXPR, *pbitpos, | |
576 | bitsize_int (off_align)); | |
577 | ||
578 | *poffset | |
579 | = size_binop (PLUS_EXPR, *poffset, | |
455f19cb MM |
580 | size_binop (MULT_EXPR, |
581 | fold_convert (sizetype, extra_aligns), | |
f2704b9f | 582 | size_int (off_align / BITS_PER_UNIT))); |
786de7eb | 583 | |
f2704b9f RK |
584 | *pbitpos |
585 | = size_binop (FLOOR_MOD_EXPR, *pbitpos, bitsize_int (off_align)); | |
586 | } | |
587 | } | |
588 | ||
770ae6cc | 589 | /* Print debugging information about the information in RLI. */ |
cc9d4a85 | 590 | |
770ae6cc | 591 | void |
46c5ad27 | 592 | debug_rli (record_layout_info rli) |
cc9d4a85 | 593 | { |
770ae6cc RK |
594 | print_node_brief (stderr, "type", rli->t, 0); |
595 | print_node_brief (stderr, "\noffset", rli->offset, 0); | |
596 | print_node_brief (stderr, " bitpos", rli->bitpos, 0); | |
cc9d4a85 | 597 | |
78d55cc8 JM |
598 | fprintf (stderr, "\naligns: rec = %u, unpack = %u, off = %u\n", |
599 | rli->record_align, rli->unpacked_align, | |
e0cea8d9 | 600 | rli->offset_align); |
770ae6cc RK |
601 | if (rli->packed_maybe_necessary) |
602 | fprintf (stderr, "packed may be necessary\n"); | |
603 | ||
604 | if (rli->pending_statics) | |
605 | { | |
606 | fprintf (stderr, "pending statics:\n"); | |
607 | debug_tree (rli->pending_statics); | |
608 | } | |
609 | } | |
610 | ||
611 | /* Given an RLI with a possibly-incremented BITPOS, adjust OFFSET and | |
612 | BITPOS if necessary to keep BITPOS below OFFSET_ALIGN. */ | |
613 | ||
614 | void | |
46c5ad27 | 615 | normalize_rli (record_layout_info rli) |
770ae6cc | 616 | { |
f2704b9f | 617 | normalize_offset (&rli->offset, &rli->bitpos, rli->offset_align); |
770ae6cc | 618 | } |
cc9d4a85 | 619 | |
770ae6cc RK |
620 | /* Returns the size in bytes allocated so far. */ |
621 | ||
622 | tree | |
46c5ad27 | 623 | rli_size_unit_so_far (record_layout_info rli) |
770ae6cc | 624 | { |
f2704b9f | 625 | return byte_from_pos (rli->offset, rli->bitpos); |
770ae6cc RK |
626 | } |
627 | ||
628 | /* Returns the size in bits allocated so far. */ | |
629 | ||
630 | tree | |
46c5ad27 | 631 | rli_size_so_far (record_layout_info rli) |
770ae6cc | 632 | { |
f2704b9f | 633 | return bit_from_pos (rli->offset, rli->bitpos); |
770ae6cc RK |
634 | } |
635 | ||
0645ba8f MM |
636 | /* FIELD is about to be added to RLI->T. The alignment (in bits) of |
637 | the next available location is given by KNOWN_ALIGN. Update the | |
638 | variable alignment fields in RLI, and return the alignment to give | |
639 | the FIELD. */ | |
770ae6cc | 640 | |
6de9cd9a | 641 | unsigned int |
46c5ad27 AJ |
642 | update_alignment_for_field (record_layout_info rli, tree field, |
643 | unsigned int known_align) | |
9328904c MM |
644 | { |
645 | /* The alignment required for FIELD. */ | |
646 | unsigned int desired_align; | |
9328904c MM |
647 | /* The type of this field. */ |
648 | tree type = TREE_TYPE (field); | |
0645ba8f MM |
649 | /* True if the field was explicitly aligned by the user. */ |
650 | bool user_align; | |
78d55cc8 | 651 | bool is_bitfield; |
9328904c | 652 | |
78d55cc8 JM |
653 | /* Lay out the field so we know what alignment it needs. */ |
654 | layout_decl (field, known_align); | |
770ae6cc | 655 | desired_align = DECL_ALIGN (field); |
11cf4d18 | 656 | user_align = DECL_USER_ALIGN (field); |
770ae6cc | 657 | |
78d55cc8 JM |
658 | is_bitfield = (type != error_mark_node |
659 | && DECL_BIT_FIELD_TYPE (field) | |
660 | && ! integer_zerop (TYPE_SIZE (type))); | |
7306ed3f | 661 | |
9328904c MM |
662 | /* Record must have at least as much alignment as any field. |
663 | Otherwise, the alignment of the field within the record is | |
664 | meaningless. */ | |
245f1bfa | 665 | if (is_bitfield && targetm.ms_bitfield_layout_p (rli->t)) |
f913c102 | 666 | { |
e4850f36 DR |
667 | /* Here, the alignment of the underlying type of a bitfield can |
668 | affect the alignment of a record; even a zero-sized field | |
669 | can do this. The alignment should be to the alignment of | |
670 | the type, except that for zero-size bitfields this only | |
0e9e1e0a | 671 | applies if there was an immediately prior, nonzero-size |
e4850f36 DR |
672 | bitfield. (That's the way it is, experimentally.) */ |
673 | if (! integer_zerop (DECL_SIZE (field)) | |
46c5ad27 AJ |
674 | ? ! DECL_PACKED (field) |
675 | : (rli->prev_field | |
676 | && DECL_BIT_FIELD_TYPE (rli->prev_field) | |
677 | && ! integer_zerop (DECL_SIZE (rli->prev_field)))) | |
f913c102 | 678 | { |
e4850f36 DR |
679 | unsigned int type_align = TYPE_ALIGN (type); |
680 | type_align = MAX (type_align, desired_align); | |
681 | if (maximum_field_alignment != 0) | |
682 | type_align = MIN (type_align, maximum_field_alignment); | |
683 | rli->record_align = MAX (rli->record_align, type_align); | |
f913c102 AO |
684 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
685 | } | |
786de7eb | 686 | } |
3c12fcc2 | 687 | #ifdef PCC_BITFIELD_TYPE_MATTERS |
78d55cc8 | 688 | else if (is_bitfield && PCC_BITFIELD_TYPE_MATTERS) |
9328904c | 689 | { |
8dc65b6e | 690 | /* Named bit-fields cause the entire structure to have the |
13c1cd82 PB |
691 | alignment implied by their type. Some targets also apply the same |
692 | rules to unnamed bitfields. */ | |
693 | if (DECL_NAME (field) != 0 | |
694 | || targetm.align_anon_bitfield ()) | |
7306ed3f | 695 | { |
9328904c | 696 | unsigned int type_align = TYPE_ALIGN (type); |
729a2125 | 697 | |
ad9335eb JJ |
698 | #ifdef ADJUST_FIELD_ALIGN |
699 | if (! TYPE_USER_ALIGN (type)) | |
700 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
701 | #endif | |
702 | ||
9328904c MM |
703 | if (maximum_field_alignment != 0) |
704 | type_align = MIN (type_align, maximum_field_alignment); | |
705 | else if (DECL_PACKED (field)) | |
706 | type_align = MIN (type_align, BITS_PER_UNIT); | |
e2301a83 | 707 | |
8dc65b6e MM |
708 | /* The alignment of the record is increased to the maximum |
709 | of the current alignment, the alignment indicated on the | |
710 | field (i.e., the alignment specified by an __aligned__ | |
711 | attribute), and the alignment indicated by the type of | |
712 | the field. */ | |
713 | rli->record_align = MAX (rli->record_align, desired_align); | |
9328904c | 714 | rli->record_align = MAX (rli->record_align, type_align); |
8dc65b6e | 715 | |
3c12fcc2 | 716 | if (warn_packed) |
e0cea8d9 | 717 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
daf06049 | 718 | user_align |= TYPE_USER_ALIGN (type); |
3c12fcc2 | 719 | } |
9328904c | 720 | } |
9328904c | 721 | #endif |
78d55cc8 | 722 | else |
9328904c MM |
723 | { |
724 | rli->record_align = MAX (rli->record_align, desired_align); | |
770ae6cc | 725 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
9328904c | 726 | } |
3c12fcc2 | 727 | |
0645ba8f MM |
728 | TYPE_USER_ALIGN (rli->t) |= user_align; |
729 | ||
730 | return desired_align; | |
731 | } | |
732 | ||
733 | /* Called from place_field to handle unions. */ | |
734 | ||
735 | static void | |
46c5ad27 | 736 | place_union_field (record_layout_info rli, tree field) |
0645ba8f MM |
737 | { |
738 | update_alignment_for_field (rli, field, /*known_align=*/0); | |
739 | ||
740 | DECL_FIELD_OFFSET (field) = size_zero_node; | |
741 | DECL_FIELD_BIT_OFFSET (field) = bitsize_zero_node; | |
742 | SET_DECL_OFFSET_ALIGN (field, BIGGEST_ALIGNMENT); | |
743 | ||
744 | /* We assume the union's size will be a multiple of a byte so we don't | |
745 | bother with BITPOS. */ | |
746 | if (TREE_CODE (rli->t) == UNION_TYPE) | |
747 | rli->offset = size_binop (MAX_EXPR, rli->offset, DECL_SIZE_UNIT (field)); | |
748 | else if (TREE_CODE (rli->t) == QUAL_UNION_TYPE) | |
4845b383 KH |
749 | rli->offset = fold_build3 (COND_EXPR, sizetype, |
750 | DECL_QUALIFIER (field), | |
751 | DECL_SIZE_UNIT (field), rli->offset); | |
0645ba8f MM |
752 | } |
753 | ||
b8089d8d | 754 | #if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED) |
4977bab6 | 755 | /* A bitfield of SIZE with a required access alignment of ALIGN is allocated |
272d0bee | 756 | at BYTE_OFFSET / BIT_OFFSET. Return nonzero if the field would span more |
4977bab6 ZW |
757 | units of alignment than the underlying TYPE. */ |
758 | static int | |
46c5ad27 AJ |
759 | excess_unit_span (HOST_WIDE_INT byte_offset, HOST_WIDE_INT bit_offset, |
760 | HOST_WIDE_INT size, HOST_WIDE_INT align, tree type) | |
4977bab6 ZW |
761 | { |
762 | /* Note that the calculation of OFFSET might overflow; we calculate it so | |
763 | that we still get the right result as long as ALIGN is a power of two. */ | |
764 | unsigned HOST_WIDE_INT offset = byte_offset * BITS_PER_UNIT + bit_offset; | |
765 | ||
766 | offset = offset % align; | |
767 | return ((offset + size + align - 1) / align | |
768 | > ((unsigned HOST_WIDE_INT) tree_low_cst (TYPE_SIZE (type), 1) | |
769 | / align)); | |
770 | } | |
b8089d8d | 771 | #endif |
4977bab6 | 772 | |
0645ba8f MM |
773 | /* RLI contains information about the layout of a RECORD_TYPE. FIELD |
774 | is a FIELD_DECL to be added after those fields already present in | |
775 | T. (FIELD is not actually added to the TYPE_FIELDS list here; | |
776 | callers that desire that behavior must manually perform that step.) */ | |
777 | ||
778 | void | |
46c5ad27 | 779 | place_field (record_layout_info rli, tree field) |
0645ba8f MM |
780 | { |
781 | /* The alignment required for FIELD. */ | |
782 | unsigned int desired_align; | |
783 | /* The alignment FIELD would have if we just dropped it into the | |
784 | record as it presently stands. */ | |
785 | unsigned int known_align; | |
786 | unsigned int actual_align; | |
787 | /* The type of this field. */ | |
788 | tree type = TREE_TYPE (field); | |
789 | ||
790 | if (TREE_CODE (field) == ERROR_MARK || TREE_CODE (type) == ERROR_MARK) | |
791 | return; | |
792 | ||
793 | /* If FIELD is static, then treat it like a separate variable, not | |
794 | really like a structure field. If it is a FUNCTION_DECL, it's a | |
795 | method. In both cases, all we do is lay out the decl, and we do | |
796 | it *after* the record is laid out. */ | |
797 | if (TREE_CODE (field) == VAR_DECL) | |
798 | { | |
799 | rli->pending_statics = tree_cons (NULL_TREE, field, | |
800 | rli->pending_statics); | |
801 | return; | |
802 | } | |
803 | ||
804 | /* Enumerators and enum types which are local to this class need not | |
805 | be laid out. Likewise for initialized constant fields. */ | |
806 | else if (TREE_CODE (field) != FIELD_DECL) | |
807 | return; | |
808 | ||
809 | /* Unions are laid out very differently than records, so split | |
810 | that code off to another function. */ | |
811 | else if (TREE_CODE (rli->t) != RECORD_TYPE) | |
812 | { | |
813 | place_union_field (rli, field); | |
814 | return; | |
815 | } | |
816 | ||
817 | /* Work out the known alignment so far. Note that A & (-A) is the | |
818 | value of the least-significant bit in A that is one. */ | |
819 | if (! integer_zerop (rli->bitpos)) | |
820 | known_align = (tree_low_cst (rli->bitpos, 1) | |
821 | & - tree_low_cst (rli->bitpos, 1)); | |
822 | else if (integer_zerop (rli->offset)) | |
823 | known_align = BIGGEST_ALIGNMENT; | |
824 | else if (host_integerp (rli->offset, 1)) | |
825 | known_align = (BITS_PER_UNIT | |
826 | * (tree_low_cst (rli->offset, 1) | |
827 | & - tree_low_cst (rli->offset, 1))); | |
828 | else | |
829 | known_align = rli->offset_align; | |
46c5ad27 | 830 | |
0645ba8f MM |
831 | desired_align = update_alignment_for_field (rli, field, known_align); |
832 | ||
9328904c MM |
833 | if (warn_packed && DECL_PACKED (field)) |
834 | { | |
78d55cc8 | 835 | if (known_align >= TYPE_ALIGN (type)) |
3c12fcc2 | 836 | { |
9328904c | 837 | if (TYPE_ALIGN (type) > desired_align) |
3c12fcc2 | 838 | { |
9328904c | 839 | if (STRICT_ALIGNMENT) |
d4ee4d25 | 840 | warning (0, "%Jpacked attribute causes inefficient alignment " |
971801ff | 841 | "for %qD", field, field); |
9328904c | 842 | else |
d4ee4d25 | 843 | warning (0, "%Jpacked attribute is unnecessary for %qD", |
ddd2d57e | 844 | field, field); |
3c12fcc2 | 845 | } |
3c12fcc2 | 846 | } |
9328904c MM |
847 | else |
848 | rli->packed_maybe_necessary = 1; | |
849 | } | |
7306ed3f | 850 | |
9328904c MM |
851 | /* Does this field automatically have alignment it needs by virtue |
852 | of the fields that precede it and the record's own alignment? */ | |
770ae6cc | 853 | if (known_align < desired_align) |
9328904c MM |
854 | { |
855 | /* No, we need to skip space before this field. | |
856 | Bump the cumulative size to multiple of field alignment. */ | |
7306ed3f | 857 | |
9328904c | 858 | if (warn_padded) |
d4ee4d25 | 859 | warning (0, "%Jpadding struct to align %qD", field, field); |
3c12fcc2 | 860 | |
770ae6cc RK |
861 | /* If the alignment is still within offset_align, just align |
862 | the bit position. */ | |
863 | if (desired_align < rli->offset_align) | |
864 | rli->bitpos = round_up (rli->bitpos, desired_align); | |
9328904c MM |
865 | else |
866 | { | |
770ae6cc RK |
867 | /* First adjust OFFSET by the partial bits, then align. */ |
868 | rli->offset | |
869 | = size_binop (PLUS_EXPR, rli->offset, | |
455f19cb MM |
870 | fold_convert (sizetype, |
871 | size_binop (CEIL_DIV_EXPR, rli->bitpos, | |
872 | bitsize_unit_node))); | |
770ae6cc RK |
873 | rli->bitpos = bitsize_zero_node; |
874 | ||
875 | rli->offset = round_up (rli->offset, desired_align / BITS_PER_UNIT); | |
7306ed3f | 876 | } |
770ae6cc | 877 | |
b1254b72 RK |
878 | if (! TREE_CONSTANT (rli->offset)) |
879 | rli->offset_align = desired_align; | |
880 | ||
9328904c | 881 | } |
7306ed3f | 882 | |
770ae6cc RK |
883 | /* Handle compatibility with PCC. Note that if the record has any |
884 | variable-sized fields, we need not worry about compatibility. */ | |
7306ed3f | 885 | #ifdef PCC_BITFIELD_TYPE_MATTERS |
9328904c | 886 | if (PCC_BITFIELD_TYPE_MATTERS |
245f1bfa | 887 | && ! targetm.ms_bitfield_layout_p (rli->t) |
9328904c MM |
888 | && TREE_CODE (field) == FIELD_DECL |
889 | && type != error_mark_node | |
770ae6cc RK |
890 | && DECL_BIT_FIELD (field) |
891 | && ! DECL_PACKED (field) | |
9328904c | 892 | && maximum_field_alignment == 0 |
770ae6cc RK |
893 | && ! integer_zerop (DECL_SIZE (field)) |
894 | && host_integerp (DECL_SIZE (field), 1) | |
895 | && host_integerp (rli->offset, 1) | |
896 | && host_integerp (TYPE_SIZE (type), 1)) | |
9328904c MM |
897 | { |
898 | unsigned int type_align = TYPE_ALIGN (type); | |
770ae6cc RK |
899 | tree dsize = DECL_SIZE (field); |
900 | HOST_WIDE_INT field_size = tree_low_cst (dsize, 1); | |
901 | HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0); | |
902 | HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0); | |
9328904c | 903 | |
ad9335eb JJ |
904 | #ifdef ADJUST_FIELD_ALIGN |
905 | if (! TYPE_USER_ALIGN (type)) | |
906 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
907 | #endif | |
908 | ||
9328904c MM |
909 | /* A bit field may not span more units of alignment of its type |
910 | than its type itself. Advance to next boundary if necessary. */ | |
4977bab6 | 911 | if (excess_unit_span (offset, bit_offset, field_size, type_align, type)) |
770ae6cc | 912 | rli->bitpos = round_up (rli->bitpos, type_align); |
daf06049 | 913 | |
0645ba8f | 914 | TYPE_USER_ALIGN (rli->t) |= TYPE_USER_ALIGN (type); |
9328904c | 915 | } |
7306ed3f JW |
916 | #endif |
917 | ||
7306ed3f | 918 | #ifdef BITFIELD_NBYTES_LIMITED |
9328904c | 919 | if (BITFIELD_NBYTES_LIMITED |
245f1bfa | 920 | && ! targetm.ms_bitfield_layout_p (rli->t) |
9328904c MM |
921 | && TREE_CODE (field) == FIELD_DECL |
922 | && type != error_mark_node | |
923 | && DECL_BIT_FIELD_TYPE (field) | |
770ae6cc RK |
924 | && ! DECL_PACKED (field) |
925 | && ! integer_zerop (DECL_SIZE (field)) | |
926 | && host_integerp (DECL_SIZE (field), 1) | |
163d3408 | 927 | && host_integerp (rli->offset, 1) |
770ae6cc | 928 | && host_integerp (TYPE_SIZE (type), 1)) |
9328904c MM |
929 | { |
930 | unsigned int type_align = TYPE_ALIGN (type); | |
770ae6cc RK |
931 | tree dsize = DECL_SIZE (field); |
932 | HOST_WIDE_INT field_size = tree_low_cst (dsize, 1); | |
933 | HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0); | |
934 | HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0); | |
e2301a83 | 935 | |
ad9335eb JJ |
936 | #ifdef ADJUST_FIELD_ALIGN |
937 | if (! TYPE_USER_ALIGN (type)) | |
938 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
939 | #endif | |
940 | ||
9328904c MM |
941 | if (maximum_field_alignment != 0) |
942 | type_align = MIN (type_align, maximum_field_alignment); | |
943 | /* ??? This test is opposite the test in the containing if | |
944 | statement, so this code is unreachable currently. */ | |
945 | else if (DECL_PACKED (field)) | |
946 | type_align = MIN (type_align, BITS_PER_UNIT); | |
947 | ||
948 | /* A bit field may not span the unit of alignment of its type. | |
949 | Advance to next boundary if necessary. */ | |
4977bab6 | 950 | if (excess_unit_span (offset, bit_offset, field_size, type_align, type)) |
770ae6cc | 951 | rli->bitpos = round_up (rli->bitpos, type_align); |
daf06049 | 952 | |
0645ba8f | 953 | TYPE_USER_ALIGN (rli->t) |= TYPE_USER_ALIGN (type); |
9328904c | 954 | } |
7306ed3f JW |
955 | #endif |
956 | ||
e4850f36 DR |
957 | /* See the docs for TARGET_MS_BITFIELD_LAYOUT_P for details. |
958 | A subtlety: | |
959 | When a bit field is inserted into a packed record, the whole | |
960 | size of the underlying type is used by one or more same-size | |
4977bab6 | 961 | adjacent bitfields. (That is, if its long:3, 32 bits is |
e4850f36 DR |
962 | used in the record, and any additional adjacent long bitfields are |
963 | packed into the same chunk of 32 bits. However, if the size | |
964 | changes, a new field of that size is allocated.) In an unpacked | |
14b493d6 | 965 | record, this is the same as using alignment, but not equivalent |
4977bab6 | 966 | when packing. |
e4850f36 | 967 | |
14b493d6 | 968 | Note: for compatibility, we use the type size, not the type alignment |
e4850f36 DR |
969 | to determine alignment, since that matches the documentation */ |
970 | ||
245f1bfa | 971 | if (targetm.ms_bitfield_layout_p (rli->t) |
e4850f36 | 972 | && ((DECL_BIT_FIELD_TYPE (field) && ! DECL_PACKED (field)) |
46c5ad27 | 973 | || (rli->prev_field && ! DECL_PACKED (rli->prev_field)))) |
f913c102 | 974 | { |
e4850f36 | 975 | /* At this point, either the prior or current are bitfields, |
991b6592 | 976 | (possibly both), and we're dealing with MS packing. */ |
e4850f36 | 977 | tree prev_saved = rli->prev_field; |
f913c102 | 978 | |
e4850f36 | 979 | /* Is the prior field a bitfield? If so, handle "runs" of same |
991b6592 KH |
980 | type size fields. */ |
981 | if (rli->prev_field /* necessarily a bitfield if it exists. */) | |
e4850f36 DR |
982 | { |
983 | /* If both are bitfields, nonzero, and the same size, this is | |
984 | the middle of a run. Zero declared size fields are special | |
985 | and handled as "end of run". (Note: it's nonzero declared | |
986 | size, but equal type sizes!) (Since we know that both | |
987 | the current and previous fields are bitfields by the | |
988 | time we check it, DECL_SIZE must be present for both.) */ | |
989 | if (DECL_BIT_FIELD_TYPE (field) | |
990 | && !integer_zerop (DECL_SIZE (field)) | |
991 | && !integer_zerop (DECL_SIZE (rli->prev_field)) | |
0384674e RK |
992 | && host_integerp (DECL_SIZE (rli->prev_field), 0) |
993 | && host_integerp (TYPE_SIZE (type), 0) | |
e4850f36 | 994 | && simple_cst_equal (TYPE_SIZE (type), |
0384674e | 995 | TYPE_SIZE (TREE_TYPE (rli->prev_field)))) |
e4850f36 DR |
996 | { |
997 | /* We're in the middle of a run of equal type size fields; make | |
998 | sure we realign if we run out of bits. (Not decl size, | |
999 | type size!) */ | |
0384674e | 1000 | HOST_WIDE_INT bitsize = tree_low_cst (DECL_SIZE (field), 0); |
e4850f36 DR |
1001 | |
1002 | if (rli->remaining_in_alignment < bitsize) | |
1003 | { | |
991b6592 | 1004 | /* out of bits; bump up to next 'word'. */ |
5354730b | 1005 | rli->offset = DECL_FIELD_OFFSET (rli->prev_field); |
0384674e RK |
1006 | rli->bitpos |
1007 | = size_binop (PLUS_EXPR, TYPE_SIZE (type), | |
1008 | DECL_FIELD_BIT_OFFSET (rli->prev_field)); | |
e4850f36 | 1009 | rli->prev_field = field; |
0384674e RK |
1010 | rli->remaining_in_alignment |
1011 | = tree_low_cst (TYPE_SIZE (type), 0); | |
e4850f36 | 1012 | } |
0384674e | 1013 | |
e4850f36 DR |
1014 | rli->remaining_in_alignment -= bitsize; |
1015 | } | |
1016 | else | |
1017 | { | |
4977bab6 ZW |
1018 | /* End of a run: if leaving a run of bitfields of the same type |
1019 | size, we have to "use up" the rest of the bits of the type | |
e4850f36 DR |
1020 | size. |
1021 | ||
1022 | Compute the new position as the sum of the size for the prior | |
1023 | type and where we first started working on that type. | |
1024 | Note: since the beginning of the field was aligned then | |
1025 | of course the end will be too. No round needed. */ | |
1026 | ||
1027 | if (!integer_zerop (DECL_SIZE (rli->prev_field))) | |
1028 | { | |
0384674e RK |
1029 | tree type_size = TYPE_SIZE (TREE_TYPE (rli->prev_field)); |
1030 | ||
1031 | rli->bitpos | |
1032 | = size_binop (PLUS_EXPR, type_size, | |
1033 | DECL_FIELD_BIT_OFFSET (rli->prev_field)); | |
e4850f36 DR |
1034 | } |
1035 | else | |
0384674e RK |
1036 | /* We "use up" size zero fields; the code below should behave |
1037 | as if the prior field was not a bitfield. */ | |
1038 | prev_saved = NULL; | |
e4850f36 | 1039 | |
4977bab6 | 1040 | /* Cause a new bitfield to be captured, either this time (if |
991b6592 | 1041 | currently a bitfield) or next time we see one. */ |
e4850f36 DR |
1042 | if (!DECL_BIT_FIELD_TYPE(field) |
1043 | || integer_zerop (DECL_SIZE (field))) | |
0384674e | 1044 | rli->prev_field = NULL; |
e4850f36 | 1045 | } |
0384674e | 1046 | |
e4850f36 DR |
1047 | normalize_rli (rli); |
1048 | } | |
1049 | ||
1050 | /* If we're starting a new run of same size type bitfields | |
1051 | (or a run of non-bitfields), set up the "first of the run" | |
4977bab6 | 1052 | fields. |
e4850f36 DR |
1053 | |
1054 | That is, if the current field is not a bitfield, or if there | |
1055 | was a prior bitfield the type sizes differ, or if there wasn't | |
1056 | a prior bitfield the size of the current field is nonzero. | |
1057 | ||
1058 | Note: we must be sure to test ONLY the type size if there was | |
1059 | a prior bitfield and ONLY for the current field being zero if | |
1060 | there wasn't. */ | |
1061 | ||
1062 | if (!DECL_BIT_FIELD_TYPE (field) | |
4977bab6 | 1063 | || ( prev_saved != NULL |
e4850f36 | 1064 | ? !simple_cst_equal (TYPE_SIZE (type), |
0384674e RK |
1065 | TYPE_SIZE (TREE_TYPE (prev_saved))) |
1066 | : !integer_zerop (DECL_SIZE (field)) )) | |
e4850f36 | 1067 | { |
0384674e RK |
1068 | /* Never smaller than a byte for compatibility. */ |
1069 | unsigned int type_align = BITS_PER_UNIT; | |
e4850f36 | 1070 | |
4977bab6 | 1071 | /* (When not a bitfield), we could be seeing a flex array (with |
e4850f36 | 1072 | no DECL_SIZE). Since we won't be using remaining_in_alignment |
4977bab6 | 1073 | until we see a bitfield (and come by here again) we just skip |
e4850f36 | 1074 | calculating it. */ |
0384674e RK |
1075 | if (DECL_SIZE (field) != NULL |
1076 | && host_integerp (TYPE_SIZE (TREE_TYPE (field)), 0) | |
1077 | && host_integerp (DECL_SIZE (field), 0)) | |
1078 | rli->remaining_in_alignment | |
1079 | = tree_low_cst (TYPE_SIZE (TREE_TYPE(field)), 0) | |
1080 | - tree_low_cst (DECL_SIZE (field), 0); | |
e4850f36 | 1081 | |
991b6592 | 1082 | /* Now align (conventionally) for the new type. */ |
e4850f36 | 1083 | if (!DECL_PACKED(field)) |
0384674e | 1084 | type_align = MAX(TYPE_ALIGN (type), type_align); |
e4850f36 DR |
1085 | |
1086 | if (prev_saved | |
1087 | && DECL_BIT_FIELD_TYPE (prev_saved) | |
1088 | /* If the previous bit-field is zero-sized, we've already | |
1089 | accounted for its alignment needs (or ignored it, if | |
1090 | appropriate) while placing it. */ | |
1091 | && ! integer_zerop (DECL_SIZE (prev_saved))) | |
1092 | type_align = MAX (type_align, | |
1093 | TYPE_ALIGN (TREE_TYPE (prev_saved))); | |
f913c102 | 1094 | |
e4850f36 DR |
1095 | if (maximum_field_alignment != 0) |
1096 | type_align = MIN (type_align, maximum_field_alignment); | |
f913c102 | 1097 | |
e4850f36 | 1098 | rli->bitpos = round_up (rli->bitpos, type_align); |
0384674e | 1099 | |
e4850f36 | 1100 | /* If we really aligned, don't allow subsequent bitfields |
991b6592 | 1101 | to undo that. */ |
e4850f36 DR |
1102 | rli->prev_field = NULL; |
1103 | } | |
f913c102 AO |
1104 | } |
1105 | ||
770ae6cc RK |
1106 | /* Offset so far becomes the position of this field after normalizing. */ |
1107 | normalize_rli (rli); | |
1108 | DECL_FIELD_OFFSET (field) = rli->offset; | |
1109 | DECL_FIELD_BIT_OFFSET (field) = rli->bitpos; | |
2f5c7f45 | 1110 | SET_DECL_OFFSET_ALIGN (field, rli->offset_align); |
770ae6cc RK |
1111 | |
1112 | /* If this field ended up more aligned than we thought it would be (we | |
1113 | approximate this by seeing if its position changed), lay out the field | |
1114 | again; perhaps we can use an integral mode for it now. */ | |
4b6bf620 | 1115 | if (! integer_zerop (DECL_FIELD_BIT_OFFSET (field))) |
770ae6cc RK |
1116 | actual_align = (tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1) |
1117 | & - tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1)); | |
4b6bf620 RK |
1118 | else if (integer_zerop (DECL_FIELD_OFFSET (field))) |
1119 | actual_align = BIGGEST_ALIGNMENT; | |
770ae6cc RK |
1120 | else if (host_integerp (DECL_FIELD_OFFSET (field), 1)) |
1121 | actual_align = (BITS_PER_UNIT | |
1122 | * (tree_low_cst (DECL_FIELD_OFFSET (field), 1) | |
1123 | & - tree_low_cst (DECL_FIELD_OFFSET (field), 1))); | |
9328904c | 1124 | else |
770ae6cc RK |
1125 | actual_align = DECL_OFFSET_ALIGN (field); |
1126 | ||
1127 | if (known_align != actual_align) | |
1128 | layout_decl (field, actual_align); | |
1129 | ||
991b6592 | 1130 | /* Only the MS bitfields use this. */ |
e4850f36 DR |
1131 | if (rli->prev_field == NULL && DECL_BIT_FIELD_TYPE(field)) |
1132 | rli->prev_field = field; | |
f913c102 | 1133 | |
770ae6cc RK |
1134 | /* Now add size of this field to the size of the record. If the size is |
1135 | not constant, treat the field as being a multiple of bytes and just | |
1136 | adjust the offset, resetting the bit position. Otherwise, apportion the | |
1137 | size amongst the bit position and offset. First handle the case of an | |
1138 | unspecified size, which can happen when we have an invalid nested struct | |
1139 | definition, such as struct j { struct j { int i; } }. The error message | |
1140 | is printed in finish_struct. */ | |
1141 | if (DECL_SIZE (field) == 0) | |
1142 | /* Do nothing. */; | |
67011d81 RK |
1143 | else if (TREE_CODE (DECL_SIZE_UNIT (field)) != INTEGER_CST |
1144 | || TREE_CONSTANT_OVERFLOW (DECL_SIZE_UNIT (field))) | |
9328904c | 1145 | { |
770ae6cc RK |
1146 | rli->offset |
1147 | = size_binop (PLUS_EXPR, rli->offset, | |
455f19cb MM |
1148 | fold_convert (sizetype, |
1149 | size_binop (CEIL_DIV_EXPR, rli->bitpos, | |
1150 | bitsize_unit_node))); | |
770ae6cc RK |
1151 | rli->offset |
1152 | = size_binop (PLUS_EXPR, rli->offset, DECL_SIZE_UNIT (field)); | |
1153 | rli->bitpos = bitsize_zero_node; | |
3923e410 | 1154 | rli->offset_align = MIN (rli->offset_align, desired_align); |
9328904c | 1155 | } |
9328904c MM |
1156 | else |
1157 | { | |
770ae6cc RK |
1158 | rli->bitpos = size_binop (PLUS_EXPR, rli->bitpos, DECL_SIZE (field)); |
1159 | normalize_rli (rli); | |
7306ed3f | 1160 | } |
9328904c | 1161 | } |
7306ed3f | 1162 | |
9328904c MM |
1163 | /* Assuming that all the fields have been laid out, this function uses |
1164 | RLI to compute the final TYPE_SIZE, TYPE_ALIGN, etc. for the type | |
14b493d6 | 1165 | indicated by RLI. */ |
7306ed3f | 1166 | |
9328904c | 1167 | static void |
46c5ad27 | 1168 | finalize_record_size (record_layout_info rli) |
9328904c | 1169 | { |
770ae6cc RK |
1170 | tree unpadded_size, unpadded_size_unit; |
1171 | ||
65e14bf5 RK |
1172 | /* Now we want just byte and bit offsets, so set the offset alignment |
1173 | to be a byte and then normalize. */ | |
1174 | rli->offset_align = BITS_PER_UNIT; | |
1175 | normalize_rli (rli); | |
7306ed3f JW |
1176 | |
1177 | /* Determine the desired alignment. */ | |
1178 | #ifdef ROUND_TYPE_ALIGN | |
9328904c | 1179 | TYPE_ALIGN (rli->t) = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t), |
b451555a | 1180 | rli->record_align); |
7306ed3f | 1181 | #else |
9328904c | 1182 | TYPE_ALIGN (rli->t) = MAX (TYPE_ALIGN (rli->t), rli->record_align); |
7306ed3f JW |
1183 | #endif |
1184 | ||
65e14bf5 RK |
1185 | /* Compute the size so far. Be sure to allow for extra bits in the |
1186 | size in bytes. We have guaranteed above that it will be no more | |
1187 | than a single byte. */ | |
1188 | unpadded_size = rli_size_so_far (rli); | |
1189 | unpadded_size_unit = rli_size_unit_so_far (rli); | |
1190 | if (! integer_zerop (rli->bitpos)) | |
1191 | unpadded_size_unit | |
1192 | = size_binop (PLUS_EXPR, unpadded_size_unit, size_one_node); | |
770ae6cc | 1193 | |
f9da5064 | 1194 | /* Round the size up to be a multiple of the required alignment. */ |
770ae6cc | 1195 | TYPE_SIZE (rli->t) = round_up (unpadded_size, TYPE_ALIGN (rli->t)); |
a4e9ffe5 RK |
1196 | TYPE_SIZE_UNIT (rli->t) |
1197 | = round_up (unpadded_size_unit, TYPE_ALIGN_UNIT (rli->t)); | |
729a2125 | 1198 | |
770ae6cc RK |
1199 | if (warn_padded && TREE_CONSTANT (unpadded_size) |
1200 | && simple_cst_equal (unpadded_size, TYPE_SIZE (rli->t)) == 0) | |
d4ee4d25 | 1201 | warning (0, "padding struct size to alignment boundary"); |
786de7eb | 1202 | |
770ae6cc RK |
1203 | if (warn_packed && TREE_CODE (rli->t) == RECORD_TYPE |
1204 | && TYPE_PACKED (rli->t) && ! rli->packed_maybe_necessary | |
1205 | && TREE_CONSTANT (unpadded_size)) | |
3c12fcc2 GM |
1206 | { |
1207 | tree unpacked_size; | |
729a2125 | 1208 | |
3c12fcc2 | 1209 | #ifdef ROUND_TYPE_ALIGN |
9328904c MM |
1210 | rli->unpacked_align |
1211 | = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t), rli->unpacked_align); | |
3c12fcc2 | 1212 | #else |
9328904c | 1213 | rli->unpacked_align = MAX (TYPE_ALIGN (rli->t), rli->unpacked_align); |
3c12fcc2 | 1214 | #endif |
770ae6cc | 1215 | |
9328904c | 1216 | unpacked_size = round_up (TYPE_SIZE (rli->t), rli->unpacked_align); |
9328904c | 1217 | if (simple_cst_equal (unpacked_size, TYPE_SIZE (rli->t))) |
3c12fcc2 | 1218 | { |
770ae6cc RK |
1219 | TYPE_PACKED (rli->t) = 0; |
1220 | ||
9328904c | 1221 | if (TYPE_NAME (rli->t)) |
3c12fcc2 | 1222 | { |
63ad61ed | 1223 | const char *name; |
729a2125 | 1224 | |
9328904c MM |
1225 | if (TREE_CODE (TYPE_NAME (rli->t)) == IDENTIFIER_NODE) |
1226 | name = IDENTIFIER_POINTER (TYPE_NAME (rli->t)); | |
3c12fcc2 | 1227 | else |
9328904c | 1228 | name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (rli->t))); |
770ae6cc | 1229 | |
3c12fcc2 | 1230 | if (STRICT_ALIGNMENT) |
d4ee4d25 | 1231 | warning (0, "packed attribute causes inefficient " |
971801ff | 1232 | "alignment for %qs", name); |
3c12fcc2 | 1233 | else |
d4ee4d25 | 1234 | warning (0, "packed attribute is unnecessary for %qs", name); |
3c12fcc2 GM |
1235 | } |
1236 | else | |
1237 | { | |
1238 | if (STRICT_ALIGNMENT) | |
d4ee4d25 | 1239 | warning (0, "packed attribute causes inefficient alignment"); |
3c12fcc2 | 1240 | else |
d4ee4d25 | 1241 | warning (0, "packed attribute is unnecessary"); |
3c12fcc2 GM |
1242 | } |
1243 | } | |
3c12fcc2 | 1244 | } |
9328904c MM |
1245 | } |
1246 | ||
1247 | /* Compute the TYPE_MODE for the TYPE (which is a RECORD_TYPE). */ | |
7306ed3f | 1248 | |
65e14bf5 | 1249 | void |
46c5ad27 | 1250 | compute_record_mode (tree type) |
9328904c | 1251 | { |
770ae6cc RK |
1252 | tree field; |
1253 | enum machine_mode mode = VOIDmode; | |
1254 | ||
9328904c MM |
1255 | /* Most RECORD_TYPEs have BLKmode, so we start off assuming that. |
1256 | However, if possible, we use a mode that fits in a register | |
1257 | instead, in order to allow for better optimization down the | |
1258 | line. */ | |
1259 | TYPE_MODE (type) = BLKmode; | |
9328904c | 1260 | |
770ae6cc RK |
1261 | if (! host_integerp (TYPE_SIZE (type), 1)) |
1262 | return; | |
9328904c | 1263 | |
770ae6cc RK |
1264 | /* A record which has any BLKmode members must itself be |
1265 | BLKmode; it can't go in a register. Unless the member is | |
1266 | BLKmode only because it isn't aligned. */ | |
1267 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) | |
1268 | { | |
770ae6cc RK |
1269 | if (TREE_CODE (field) != FIELD_DECL) |
1270 | continue; | |
9328904c | 1271 | |
770ae6cc RK |
1272 | if (TREE_CODE (TREE_TYPE (field)) == ERROR_MARK |
1273 | || (TYPE_MODE (TREE_TYPE (field)) == BLKmode | |
7a06d606 RK |
1274 | && ! TYPE_NO_FORCE_BLK (TREE_TYPE (field)) |
1275 | && !(TYPE_SIZE (TREE_TYPE (field)) != 0 | |
1276 | && integer_zerop (TYPE_SIZE (TREE_TYPE (field))))) | |
770ae6cc | 1277 | || ! host_integerp (bit_position (field), 1) |
6a9f6727 | 1278 | || DECL_SIZE (field) == 0 |
770ae6cc RK |
1279 | || ! host_integerp (DECL_SIZE (field), 1)) |
1280 | return; | |
1281 | ||
770ae6cc RK |
1282 | /* If this field is the whole struct, remember its mode so |
1283 | that, say, we can put a double in a class into a DF | |
a8ca7756 JW |
1284 | register instead of forcing it to live in the stack. */ |
1285 | if (simple_cst_equal (TYPE_SIZE (type), DECL_SIZE (field))) | |
770ae6cc | 1286 | mode = DECL_MODE (field); |
9328904c | 1287 | |
31a02448 | 1288 | #ifdef MEMBER_TYPE_FORCES_BLK |
770ae6cc RK |
1289 | /* With some targets, eg. c4x, it is sub-optimal |
1290 | to access an aligned BLKmode structure as a scalar. */ | |
0d7839da | 1291 | |
182e515e | 1292 | if (MEMBER_TYPE_FORCES_BLK (field, mode)) |
770ae6cc | 1293 | return; |
31a02448 | 1294 | #endif /* MEMBER_TYPE_FORCES_BLK */ |
770ae6cc | 1295 | } |
9328904c | 1296 | |
897f610b RS |
1297 | TYPE_MODE (type) = mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1); |
1298 | ||
1299 | /* If we only have one real field; use its mode if that mode's size | |
1300 | matches the type's size. This only applies to RECORD_TYPE. This | |
1301 | does not apply to unions. */ | |
1302 | if (TREE_CODE (type) == RECORD_TYPE && mode != VOIDmode | |
1303 | && GET_MODE_SIZE (mode) == GET_MODE_SIZE (TYPE_MODE (type))) | |
770ae6cc | 1304 | TYPE_MODE (type) = mode; |
770ae6cc RK |
1305 | |
1306 | /* If structure's known alignment is less than what the scalar | |
1307 | mode would need, and it matters, then stick with BLKmode. */ | |
1308 | if (TYPE_MODE (type) != BLKmode | |
1309 | && STRICT_ALIGNMENT | |
1310 | && ! (TYPE_ALIGN (type) >= BIGGEST_ALIGNMENT | |
1311 | || TYPE_ALIGN (type) >= GET_MODE_ALIGNMENT (TYPE_MODE (type)))) | |
1312 | { | |
1313 | /* If this is the only reason this type is BLKmode, then | |
1314 | don't force containing types to be BLKmode. */ | |
1315 | TYPE_NO_FORCE_BLK (type) = 1; | |
1316 | TYPE_MODE (type) = BLKmode; | |
9328904c | 1317 | } |
7306ed3f | 1318 | } |
9328904c MM |
1319 | |
1320 | /* Compute TYPE_SIZE and TYPE_ALIGN for TYPE, once it has been laid | |
1321 | out. */ | |
1322 | ||
1323 | static void | |
46c5ad27 | 1324 | finalize_type_size (tree type) |
9328904c MM |
1325 | { |
1326 | /* Normally, use the alignment corresponding to the mode chosen. | |
1327 | However, where strict alignment is not required, avoid | |
1328 | over-aligning structures, since most compilers do not do this | |
1329 | alignment. */ | |
1330 | ||
1331 | if (TYPE_MODE (type) != BLKmode && TYPE_MODE (type) != VOIDmode | |
1332 | && (STRICT_ALIGNMENT | |
1333 | || (TREE_CODE (type) != RECORD_TYPE && TREE_CODE (type) != UNION_TYPE | |
1334 | && TREE_CODE (type) != QUAL_UNION_TYPE | |
1335 | && TREE_CODE (type) != ARRAY_TYPE))) | |
11cf4d18 JJ |
1336 | { |
1337 | TYPE_ALIGN (type) = GET_MODE_ALIGNMENT (TYPE_MODE (type)); | |
1338 | TYPE_USER_ALIGN (type) = 0; | |
1339 | } | |
9328904c MM |
1340 | |
1341 | /* Do machine-dependent extra alignment. */ | |
1342 | #ifdef ROUND_TYPE_ALIGN | |
1343 | TYPE_ALIGN (type) | |
1344 | = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (type), BITS_PER_UNIT); | |
1345 | #endif | |
1346 | ||
9328904c | 1347 | /* If we failed to find a simple way to calculate the unit size |
770ae6cc | 1348 | of the type, find it by division. */ |
9328904c MM |
1349 | if (TYPE_SIZE_UNIT (type) == 0 && TYPE_SIZE (type) != 0) |
1350 | /* TYPE_SIZE (type) is computed in bitsizetype. After the division, the | |
1351 | result will fit in sizetype. We will get more efficient code using | |
1352 | sizetype, so we force a conversion. */ | |
1353 | TYPE_SIZE_UNIT (type) | |
455f19cb MM |
1354 | = fold_convert (sizetype, |
1355 | size_binop (FLOOR_DIV_EXPR, TYPE_SIZE (type), | |
1356 | bitsize_unit_node)); | |
9328904c | 1357 | |
770ae6cc RK |
1358 | if (TYPE_SIZE (type) != 0) |
1359 | { | |
770ae6cc | 1360 | TYPE_SIZE (type) = round_up (TYPE_SIZE (type), TYPE_ALIGN (type)); |
a4e9ffe5 RK |
1361 | TYPE_SIZE_UNIT (type) = round_up (TYPE_SIZE_UNIT (type), |
1362 | TYPE_ALIGN_UNIT (type)); | |
770ae6cc RK |
1363 | } |
1364 | ||
1365 | /* Evaluate nonconstant sizes only once, either now or as soon as safe. */ | |
1366 | if (TYPE_SIZE (type) != 0 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) | |
1367 | TYPE_SIZE (type) = variable_size (TYPE_SIZE (type)); | |
9328904c MM |
1368 | if (TYPE_SIZE_UNIT (type) != 0 |
1369 | && TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST) | |
1370 | TYPE_SIZE_UNIT (type) = variable_size (TYPE_SIZE_UNIT (type)); | |
1371 | ||
1372 | /* Also layout any other variants of the type. */ | |
1373 | if (TYPE_NEXT_VARIANT (type) | |
1374 | || type != TYPE_MAIN_VARIANT (type)) | |
1375 | { | |
1376 | tree variant; | |
1377 | /* Record layout info of this variant. */ | |
1378 | tree size = TYPE_SIZE (type); | |
1379 | tree size_unit = TYPE_SIZE_UNIT (type); | |
1380 | unsigned int align = TYPE_ALIGN (type); | |
11cf4d18 | 1381 | unsigned int user_align = TYPE_USER_ALIGN (type); |
9328904c MM |
1382 | enum machine_mode mode = TYPE_MODE (type); |
1383 | ||
1384 | /* Copy it into all variants. */ | |
1385 | for (variant = TYPE_MAIN_VARIANT (type); | |
1386 | variant != 0; | |
1387 | variant = TYPE_NEXT_VARIANT (variant)) | |
1388 | { | |
1389 | TYPE_SIZE (variant) = size; | |
1390 | TYPE_SIZE_UNIT (variant) = size_unit; | |
1391 | TYPE_ALIGN (variant) = align; | |
11cf4d18 | 1392 | TYPE_USER_ALIGN (variant) = user_align; |
9328904c MM |
1393 | TYPE_MODE (variant) = mode; |
1394 | } | |
1395 | } | |
1396 | } | |
1397 | ||
1398 | /* Do all of the work required to layout the type indicated by RLI, | |
1399 | once the fields have been laid out. This function will call `free' | |
17bbb839 MM |
1400 | for RLI, unless FREE_P is false. Passing a value other than false |
1401 | for FREE_P is bad practice; this option only exists to support the | |
1402 | G++ 3.2 ABI. */ | |
9328904c MM |
1403 | |
1404 | void | |
46c5ad27 | 1405 | finish_record_layout (record_layout_info rli, int free_p) |
9328904c | 1406 | { |
770ae6cc RK |
1407 | /* Compute the final size. */ |
1408 | finalize_record_size (rli); | |
1409 | ||
1410 | /* Compute the TYPE_MODE for the record. */ | |
1411 | compute_record_mode (rli->t); | |
cc9d4a85 | 1412 | |
8d8238b6 JM |
1413 | /* Perform any last tweaks to the TYPE_SIZE, etc. */ |
1414 | finalize_type_size (rli->t); | |
1415 | ||
9328904c MM |
1416 | /* Lay out any static members. This is done now because their type |
1417 | may use the record's type. */ | |
1418 | while (rli->pending_statics) | |
1419 | { | |
1420 | layout_decl (TREE_VALUE (rli->pending_statics), 0); | |
1421 | rli->pending_statics = TREE_CHAIN (rli->pending_statics); | |
1422 | } | |
cc9d4a85 | 1423 | |
9328904c | 1424 | /* Clean up. */ |
17bbb839 MM |
1425 | if (free_p) |
1426 | free (rli); | |
9328904c | 1427 | } |
7306ed3f | 1428 | \f |
4977bab6 ZW |
1429 | |
1430 | /* Finish processing a builtin RECORD_TYPE type TYPE. It's name is | |
1431 | NAME, its fields are chained in reverse on FIELDS. | |
1432 | ||
1433 | If ALIGN_TYPE is non-null, it is given the same alignment as | |
1434 | ALIGN_TYPE. */ | |
1435 | ||
1436 | void | |
46c5ad27 AJ |
1437 | finish_builtin_struct (tree type, const char *name, tree fields, |
1438 | tree align_type) | |
4977bab6 ZW |
1439 | { |
1440 | tree tail, next; | |
1441 | ||
1442 | for (tail = NULL_TREE; fields; tail = fields, fields = next) | |
1443 | { | |
1444 | DECL_FIELD_CONTEXT (fields) = type; | |
1445 | next = TREE_CHAIN (fields); | |
1446 | TREE_CHAIN (fields) = tail; | |
1447 | } | |
1448 | TYPE_FIELDS (type) = tail; | |
1449 | ||
1450 | if (align_type) | |
1451 | { | |
1452 | TYPE_ALIGN (type) = TYPE_ALIGN (align_type); | |
1453 | TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (align_type); | |
1454 | } | |
1455 | ||
1456 | layout_type (type); | |
1457 | #if 0 /* not yet, should get fixed properly later */ | |
1458 | TYPE_NAME (type) = make_type_decl (get_identifier (name), type); | |
1459 | #else | |
1460 | TYPE_NAME (type) = build_decl (TYPE_DECL, get_identifier (name), type); | |
1461 | #endif | |
1462 | TYPE_STUB_DECL (type) = TYPE_NAME (type); | |
1463 | layout_decl (TYPE_NAME (type), 0); | |
1464 | } | |
1465 | ||
7306ed3f JW |
1466 | /* Calculate the mode, size, and alignment for TYPE. |
1467 | For an array type, calculate the element separation as well. | |
1468 | Record TYPE on the chain of permanent or temporary types | |
1469 | so that dbxout will find out about it. | |
1470 | ||
1471 | TYPE_SIZE of a type is nonzero if the type has been laid out already. | |
1472 | layout_type does nothing on such a type. | |
1473 | ||
1474 | If the type is incomplete, its TYPE_SIZE remains zero. */ | |
1475 | ||
1476 | void | |
46c5ad27 | 1477 | layout_type (tree type) |
7306ed3f | 1478 | { |
41374e13 | 1479 | gcc_assert (type); |
7306ed3f | 1480 | |
6de9cd9a DN |
1481 | if (type == error_mark_node) |
1482 | return; | |
1483 | ||
7306ed3f JW |
1484 | /* Do nothing if type has been laid out before. */ |
1485 | if (TYPE_SIZE (type)) | |
1486 | return; | |
1487 | ||
7306ed3f JW |
1488 | switch (TREE_CODE (type)) |
1489 | { | |
1490 | case LANG_TYPE: | |
1491 | /* This kind of type is the responsibility | |
9faa82d8 | 1492 | of the language-specific code. */ |
41374e13 | 1493 | gcc_unreachable (); |
7306ed3f | 1494 | |
2d76cb1a | 1495 | case BOOLEAN_TYPE: /* Used for Java, Pascal, and Chill. */ |
e9a25f70 | 1496 | if (TYPE_PRECISION (type) == 0) |
2d76cb1a | 1497 | TYPE_PRECISION (type) = 1; /* default to one byte/boolean. */ |
d4b60170 | 1498 | |
2d76cb1a | 1499 | /* ... fall through ... */ |
e9a25f70 | 1500 | |
7306ed3f JW |
1501 | case INTEGER_TYPE: |
1502 | case ENUMERAL_TYPE: | |
fc69eca0 | 1503 | case CHAR_TYPE: |
e2a77f99 RK |
1504 | if (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST |
1505 | && tree_int_cst_sgn (TYPE_MIN_VALUE (type)) >= 0) | |
8df83eae | 1506 | TYPE_UNSIGNED (type) = 1; |
7306ed3f | 1507 | |
5e9bec99 RK |
1508 | TYPE_MODE (type) = smallest_mode_for_size (TYPE_PRECISION (type), |
1509 | MODE_INT); | |
06ceef4e | 1510 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1511 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1512 | break; |
1513 | ||
1514 | case REAL_TYPE: | |
1515 | TYPE_MODE (type) = mode_for_size (TYPE_PRECISION (type), MODE_FLOAT, 0); | |
06ceef4e | 1516 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1517 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1518 | break; |
1519 | ||
1520 | case COMPLEX_TYPE: | |
8df83eae | 1521 | TYPE_UNSIGNED (type) = TYPE_UNSIGNED (TREE_TYPE (type)); |
7306ed3f JW |
1522 | TYPE_MODE (type) |
1523 | = mode_for_size (2 * TYPE_PRECISION (TREE_TYPE (type)), | |
8df83eae RK |
1524 | (TREE_CODE (TREE_TYPE (type)) == REAL_TYPE |
1525 | ? MODE_COMPLEX_FLOAT : MODE_COMPLEX_INT), | |
7306ed3f | 1526 | 0); |
06ceef4e | 1527 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1528 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1529 | break; |
1530 | ||
0b4565c9 | 1531 | case VECTOR_TYPE: |
26277d41 PB |
1532 | { |
1533 | int nunits = TYPE_VECTOR_SUBPARTS (type); | |
7d60be94 | 1534 | tree nunits_tree = build_int_cst (NULL_TREE, nunits); |
26277d41 PB |
1535 | tree innertype = TREE_TYPE (type); |
1536 | ||
41374e13 | 1537 | gcc_assert (!(nunits & (nunits - 1))); |
26277d41 PB |
1538 | |
1539 | /* Find an appropriate mode for the vector type. */ | |
1540 | if (TYPE_MODE (type) == VOIDmode) | |
1541 | { | |
1542 | enum machine_mode innermode = TYPE_MODE (innertype); | |
1543 | enum machine_mode mode; | |
1544 | ||
1545 | /* First, look for a supported vector type. */ | |
1546 | if (GET_MODE_CLASS (innermode) == MODE_FLOAT) | |
1547 | mode = MIN_MODE_VECTOR_FLOAT; | |
1548 | else | |
1549 | mode = MIN_MODE_VECTOR_INT; | |
1550 | ||
1551 | for (; mode != VOIDmode ; mode = GET_MODE_WIDER_MODE (mode)) | |
1552 | if (GET_MODE_NUNITS (mode) == nunits | |
1553 | && GET_MODE_INNER (mode) == innermode | |
f676971a | 1554 | && targetm.vector_mode_supported_p (mode)) |
26277d41 PB |
1555 | break; |
1556 | ||
1557 | /* For integers, try mapping it to a same-sized scalar mode. */ | |
1558 | if (mode == VOIDmode | |
1559 | && GET_MODE_CLASS (innermode) == MODE_INT) | |
1560 | mode = mode_for_size (nunits * GET_MODE_BITSIZE (innermode), | |
1561 | MODE_INT, 0); | |
1562 | ||
1563 | if (mode == VOIDmode || !have_regs_of_mode[mode]) | |
1564 | TYPE_MODE (type) = BLKmode; | |
1565 | else | |
1566 | TYPE_MODE (type) = mode; | |
1567 | } | |
1568 | ||
1569 | TYPE_UNSIGNED (type) = TYPE_UNSIGNED (TREE_TYPE (type)); | |
1570 | TYPE_SIZE_UNIT (type) = int_const_binop (MULT_EXPR, | |
1571 | TYPE_SIZE_UNIT (innertype), | |
1572 | nunits_tree, 0); | |
1573 | TYPE_SIZE (type) = int_const_binop (MULT_EXPR, TYPE_SIZE (innertype), | |
1574 | nunits_tree, 0); | |
e4ca3dc3 | 1575 | |
34bc6352 | 1576 | /* Always naturally align vectors. This prevents ABI changes |
e4ca3dc3 RH |
1577 | depending on whether or not native vector modes are supported. */ |
1578 | TYPE_ALIGN (type) = tree_low_cst (TYPE_SIZE (type), 0); | |
26277d41 PB |
1579 | break; |
1580 | } | |
0b4565c9 | 1581 | |
7306ed3f | 1582 | case VOID_TYPE: |
770ae6cc | 1583 | /* This is an incomplete type and so doesn't have a size. */ |
7306ed3f | 1584 | TYPE_ALIGN (type) = 1; |
11cf4d18 | 1585 | TYPE_USER_ALIGN (type) = 0; |
7306ed3f JW |
1586 | TYPE_MODE (type) = VOIDmode; |
1587 | break; | |
1588 | ||
321cb743 | 1589 | case OFFSET_TYPE: |
06ceef4e | 1590 | TYPE_SIZE (type) = bitsize_int (POINTER_SIZE); |
ead17059 | 1591 | TYPE_SIZE_UNIT (type) = size_int (POINTER_SIZE / BITS_PER_UNIT); |
25caaba8 R |
1592 | /* A pointer might be MODE_PARTIAL_INT, |
1593 | but ptrdiff_t must be integral. */ | |
1594 | TYPE_MODE (type) = mode_for_size (POINTER_SIZE, MODE_INT, 0); | |
321cb743 MT |
1595 | break; |
1596 | ||
7306ed3f JW |
1597 | case FUNCTION_TYPE: |
1598 | case METHOD_TYPE: | |
019dd4ec RK |
1599 | /* It's hard to see what the mode and size of a function ought to |
1600 | be, but we do know the alignment is FUNCTION_BOUNDARY, so | |
1601 | make it consistent with that. */ | |
1602 | TYPE_MODE (type) = mode_for_size (FUNCTION_BOUNDARY, MODE_INT, 0); | |
1603 | TYPE_SIZE (type) = bitsize_int (FUNCTION_BOUNDARY); | |
1604 | TYPE_SIZE_UNIT (type) = size_int (FUNCTION_BOUNDARY / 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)); |
8df83eae | 1619 | TYPE_UNSIGNED (type) = 1; |
b5d6a2ff RK |
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 | { | |
ad50bc8d RH |
1635 | tree ub = TYPE_MAX_VALUE (index); |
1636 | tree lb = TYPE_MIN_VALUE (index); | |
e24ff973 | 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, |
455f19cb | 1643 | fold_convert (sizetype, |
4845b383 KH |
1644 | fold_build2 (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. */ | |
8df83eae | 1669 | if (!TYPE_UNSIGNED (sizetype) |
0d3c8800 RK |
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 | 1674 | TYPE_SIZE (type) = size_binop (MULT_EXPR, element_size, |
455f19cb MM |
1675 | fold_convert (bitsizetype, |
1676 | length)); | |
ead17059 RH |
1677 | |
1678 | /* If we know the size of the element, calculate the total | |
1679 | size directly, rather than do some division thing below. | |
1680 | This optimization helps Fortran assumed-size arrays | |
1681 | (where the size of the array is determined at runtime) | |
7771032e DB |
1682 | substantially. |
1683 | Note that we can't do this in the case where the size of | |
1684 | the elements is one bit since TYPE_SIZE_UNIT cannot be | |
1685 | set correctly in that case. */ | |
fed3cef0 | 1686 | if (TYPE_SIZE_UNIT (element) != 0 && ! integer_onep (element_size)) |
d4b60170 RK |
1687 | TYPE_SIZE_UNIT (type) |
1688 | = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (element), length); | |
7306ed3f JW |
1689 | } |
1690 | ||
1691 | /* Now round the alignment and size, | |
1692 | using machine-dependent criteria if any. */ | |
1693 | ||
1694 | #ifdef ROUND_TYPE_ALIGN | |
1695 | TYPE_ALIGN (type) | |
1696 | = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (element), BITS_PER_UNIT); | |
1697 | #else | |
1698 | TYPE_ALIGN (type) = MAX (TYPE_ALIGN (element), BITS_PER_UNIT); | |
1699 | #endif | |
c163d21d | 1700 | TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (element); |
7306ed3f JW |
1701 | TYPE_MODE (type) = BLKmode; |
1702 | if (TYPE_SIZE (type) != 0 | |
31a02448 | 1703 | #ifdef MEMBER_TYPE_FORCES_BLK |
182e515e | 1704 | && ! MEMBER_TYPE_FORCES_BLK (type, VOIDmode) |
31a02448 | 1705 | #endif |
7306ed3f JW |
1706 | /* BLKmode elements force BLKmode aggregate; |
1707 | else extract/store fields may lose. */ | |
1708 | && (TYPE_MODE (TREE_TYPE (type)) != BLKmode | |
1709 | || TYPE_NO_FORCE_BLK (TREE_TYPE (type)))) | |
1710 | { | |
a1471322 RK |
1711 | /* One-element arrays get the component type's mode. */ |
1712 | if (simple_cst_equal (TYPE_SIZE (type), | |
1713 | TYPE_SIZE (TREE_TYPE (type)))) | |
1714 | TYPE_MODE (type) = TYPE_MODE (TREE_TYPE (type)); | |
1715 | else | |
1716 | TYPE_MODE (type) | |
1717 | = mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1); | |
7306ed3f | 1718 | |
72c602fc RK |
1719 | if (TYPE_MODE (type) != BLKmode |
1720 | && STRICT_ALIGNMENT && TYPE_ALIGN (type) < BIGGEST_ALIGNMENT | |
1721 | && TYPE_ALIGN (type) < GET_MODE_ALIGNMENT (TYPE_MODE (type)) | |
7306ed3f JW |
1722 | && TYPE_MODE (type) != BLKmode) |
1723 | { | |
1724 | TYPE_NO_FORCE_BLK (type) = 1; | |
1725 | TYPE_MODE (type) = BLKmode; | |
1726 | } | |
7306ed3f JW |
1727 | } |
1728 | break; | |
1729 | } | |
1730 | ||
1731 | case RECORD_TYPE: | |
cc9d4a85 MM |
1732 | case UNION_TYPE: |
1733 | case QUAL_UNION_TYPE: | |
9328904c MM |
1734 | { |
1735 | tree field; | |
1736 | record_layout_info rli; | |
1737 | ||
1738 | /* Initialize the layout information. */ | |
770ae6cc RK |
1739 | rli = start_record_layout (type); |
1740 | ||
cc9d4a85 MM |
1741 | /* If this is a QUAL_UNION_TYPE, we want to process the fields |
1742 | in the reverse order in building the COND_EXPR that denotes | |
1743 | its size. We reverse them again later. */ | |
1744 | if (TREE_CODE (type) == QUAL_UNION_TYPE) | |
1745 | TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type)); | |
770ae6cc RK |
1746 | |
1747 | /* Place all the fields. */ | |
9328904c | 1748 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) |
770ae6cc RK |
1749 | place_field (rli, field); |
1750 | ||
cc9d4a85 MM |
1751 | if (TREE_CODE (type) == QUAL_UNION_TYPE) |
1752 | TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type)); | |
770ae6cc | 1753 | |
e0cea8d9 RK |
1754 | if (lang_adjust_rli) |
1755 | (*lang_adjust_rli) (rli); | |
1756 | ||
9328904c | 1757 | /* Finish laying out the record. */ |
17bbb839 | 1758 | finish_record_layout (rli, /*free_p=*/true); |
9328904c | 1759 | } |
7306ed3f JW |
1760 | break; |
1761 | ||
7306ed3f | 1762 | default: |
41374e13 | 1763 | gcc_unreachable (); |
729a2125 | 1764 | } |
7306ed3f | 1765 | |
9328904c | 1766 | /* Compute the final TYPE_SIZE, TYPE_ALIGN, etc. for TYPE. For |
cc9d4a85 MM |
1767 | records and unions, finish_record_layout already called this |
1768 | function. */ | |
786de7eb | 1769 | if (TREE_CODE (type) != RECORD_TYPE |
cc9d4a85 MM |
1770 | && TREE_CODE (type) != UNION_TYPE |
1771 | && TREE_CODE (type) != QUAL_UNION_TYPE) | |
9328904c | 1772 | finalize_type_size (type); |
7306ed3f | 1773 | |
dc5041ab JJ |
1774 | /* If an alias set has been set for this aggregate when it was incomplete, |
1775 | force it into alias set 0. | |
1776 | This is too conservative, but we cannot call record_component_aliases | |
1777 | here because some frontends still change the aggregates after | |
1778 | layout_type. */ | |
1779 | if (AGGREGATE_TYPE_P (type) && TYPE_ALIAS_SET_KNOWN_P (type)) | |
1780 | TYPE_ALIAS_SET (type) = 0; | |
7306ed3f JW |
1781 | } |
1782 | \f | |
1783 | /* Create and return a type for signed integers of PRECISION bits. */ | |
1784 | ||
1785 | tree | |
46c5ad27 | 1786 | make_signed_type (int precision) |
7306ed3f | 1787 | { |
b3694847 | 1788 | tree type = make_node (INTEGER_TYPE); |
7306ed3f JW |
1789 | |
1790 | TYPE_PRECISION (type) = precision; | |
1791 | ||
fed3cef0 | 1792 | fixup_signed_type (type); |
7306ed3f JW |
1793 | return type; |
1794 | } | |
1795 | ||
1796 | /* Create and return a type for unsigned integers of PRECISION bits. */ | |
1797 | ||
1798 | tree | |
46c5ad27 | 1799 | make_unsigned_type (int precision) |
7306ed3f | 1800 | { |
b3694847 | 1801 | tree type = make_node (INTEGER_TYPE); |
7306ed3f JW |
1802 | |
1803 | TYPE_PRECISION (type) = precision; | |
1804 | ||
7306ed3f JW |
1805 | fixup_unsigned_type (type); |
1806 | return type; | |
1807 | } | |
fed3cef0 RK |
1808 | \f |
1809 | /* Initialize sizetype and bitsizetype to a reasonable and temporary | |
1810 | value to enable integer types to be created. */ | |
1811 | ||
1812 | void | |
8c1d6d62 | 1813 | initialize_sizetypes (bool signed_p) |
fed3cef0 RK |
1814 | { |
1815 | tree t = make_node (INTEGER_TYPE); | |
1816 | ||
fed3cef0 RK |
1817 | TYPE_MODE (t) = SImode; |
1818 | TYPE_ALIGN (t) = GET_MODE_ALIGNMENT (SImode); | |
11cf4d18 | 1819 | TYPE_USER_ALIGN (t) = 0; |
3224bead | 1820 | TYPE_IS_SIZETYPE (t) = 1; |
8c1d6d62 | 1821 | TYPE_UNSIGNED (t) = !signed_p; |
7d60be94 NS |
1822 | TYPE_SIZE (t) = build_int_cst (t, GET_MODE_BITSIZE (SImode)); |
1823 | TYPE_SIZE_UNIT (t) = build_int_cst (t, GET_MODE_SIZE (SImode)); | |
fed3cef0 | 1824 | TYPE_PRECISION (t) = GET_MODE_BITSIZE (SImode); |
7d60be94 | 1825 | TYPE_MIN_VALUE (t) = build_int_cst (t, 0); |
fed3cef0 RK |
1826 | |
1827 | /* 1000 avoids problems with possible overflow and is certainly | |
1828 | larger than any size value we'd want to be storing. */ | |
7d60be94 | 1829 | TYPE_MAX_VALUE (t) = build_int_cst (t, 1000); |
fed3cef0 | 1830 | |
fed3cef0 | 1831 | sizetype = t; |
8c1d6d62 | 1832 | bitsizetype = build_distinct_type_copy (t); |
fed3cef0 | 1833 | } |
7306ed3f | 1834 | |
8c1d6d62 NS |
1835 | /* Make sizetype a version of TYPE, and initialize *sizetype |
1836 | accordingly. We do this by overwriting the stub sizetype and | |
1837 | bitsizetype nodes created by initialize_sizetypes. This makes sure | |
1838 | that (a) anything stubby about them no longer exists, (b) any | |
1839 | INTEGER_CSTs created with such a type, remain valid. */ | |
f8dac6eb R |
1840 | |
1841 | void | |
46c5ad27 | 1842 | set_sizetype (tree type) |
f8dac6eb | 1843 | { |
d4b60170 | 1844 | int oprecision = TYPE_PRECISION (type); |
f8dac6eb | 1845 | /* The *bitsizetype types use a precision that avoids overflows when |
d4b60170 RK |
1846 | calculating signed sizes / offsets in bits. However, when |
1847 | cross-compiling from a 32 bit to a 64 bit host, we are limited to 64 bit | |
1848 | precision. */ | |
11a6092b | 1849 | int precision = MIN (oprecision + BITS_PER_UNIT_LOG + 1, |
d4b60170 | 1850 | 2 * HOST_BITS_PER_WIDE_INT); |
ad41cc2a | 1851 | tree t; |
fed3cef0 | 1852 | |
41374e13 | 1853 | gcc_assert (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (sizetype)); |
81b3411c | 1854 | |
8c1d6d62 NS |
1855 | t = build_distinct_type_copy (type); |
1856 | /* We do want to use sizetype's cache, as we will be replacing that | |
1857 | type. */ | |
1858 | TYPE_CACHED_VALUES (t) = TYPE_CACHED_VALUES (sizetype); | |
1859 | TYPE_CACHED_VALUES_P (t) = TYPE_CACHED_VALUES_P (sizetype); | |
1860 | TREE_TYPE (TYPE_CACHED_VALUES (t)) = type; | |
1861 | TYPE_UID (t) = TYPE_UID (sizetype); | |
1862 | TYPE_IS_SIZETYPE (t) = 1; | |
1863 | ||
1864 | /* Replace our original stub sizetype. */ | |
1865 | memcpy (sizetype, t, tree_size (sizetype)); | |
1866 | TYPE_MAIN_VARIANT (sizetype) = sizetype; | |
1867 | ||
1868 | t = make_node (INTEGER_TYPE); | |
1869 | TYPE_NAME (t) = get_identifier ("bit_size_type"); | |
1870 | /* We do want to use bitsizetype's cache, as we will be replacing that | |
1871 | type. */ | |
1872 | TYPE_CACHED_VALUES (t) = TYPE_CACHED_VALUES (bitsizetype); | |
1873 | TYPE_CACHED_VALUES_P (t) = TYPE_CACHED_VALUES_P (bitsizetype); | |
1874 | TYPE_PRECISION (t) = precision; | |
1875 | TYPE_UID (t) = TYPE_UID (bitsizetype); | |
1876 | TYPE_IS_SIZETYPE (t) = 1; | |
1877 | /* Replace our original stub bitsizetype. */ | |
1878 | memcpy (bitsizetype, t, tree_size (bitsizetype)); | |
1879 | ||
8df83eae | 1880 | if (TYPE_UNSIGNED (type)) |
896cced4 | 1881 | { |
8c1d6d62 NS |
1882 | fixup_unsigned_type (bitsizetype); |
1883 | ssizetype = build_distinct_type_copy (make_signed_type (oprecision)); | |
1884 | TYPE_IS_SIZETYPE (ssizetype) = 1; | |
1885 | sbitsizetype = build_distinct_type_copy (make_signed_type (precision)); | |
1886 | TYPE_IS_SIZETYPE (sbitsizetype) = 1; | |
896cced4 RH |
1887 | } |
1888 | else | |
1889 | { | |
8c1d6d62 | 1890 | fixup_signed_type (bitsizetype); |
896cced4 RH |
1891 | ssizetype = sizetype; |
1892 | sbitsizetype = bitsizetype; | |
896cced4 | 1893 | } |
fed3cef0 RK |
1894 | } |
1895 | \f | |
7b6d72fc MM |
1896 | /* TYPE is an integral type, i.e., an INTEGRAL_TYPE, ENUMERAL_TYPE, |
1897 | BOOLEAN_TYPE, or CHAR_TYPE. Set TYPE_MIN_VALUE and TYPE_MAX_VALUE | |
1898 | for TYPE, based on the PRECISION and whether or not the TYPE | |
1899 | IS_UNSIGNED. PRECISION need not correspond to a width supported | |
1900 | natively by the hardware; for example, on a machine with 8-bit, | |
1901 | 16-bit, and 32-bit register modes, PRECISION might be 7, 23, or | |
1902 | 61. */ | |
1903 | ||
1904 | void | |
1905 | set_min_and_max_values_for_integral_type (tree type, | |
1906 | int precision, | |
1907 | bool is_unsigned) | |
1908 | { | |
1909 | tree min_value; | |
1910 | tree max_value; | |
1911 | ||
1912 | if (is_unsigned) | |
1913 | { | |
7d60be94 | 1914 | min_value = build_int_cst (type, 0); |
f676971a | 1915 | max_value |
7d60be94 NS |
1916 | = build_int_cst_wide (type, precision - HOST_BITS_PER_WIDE_INT >= 0 |
1917 | ? -1 | |
1918 | : ((HOST_WIDE_INT) 1 << precision) - 1, | |
1919 | precision - HOST_BITS_PER_WIDE_INT > 0 | |
1920 | ? ((unsigned HOST_WIDE_INT) ~0 | |
1921 | >> (HOST_BITS_PER_WIDE_INT | |
1922 | - (precision - HOST_BITS_PER_WIDE_INT))) | |
1923 | : 0); | |
7b6d72fc MM |
1924 | } |
1925 | else | |
1926 | { | |
f676971a | 1927 | min_value |
7d60be94 NS |
1928 | = build_int_cst_wide (type, |
1929 | (precision - HOST_BITS_PER_WIDE_INT > 0 | |
1930 | ? 0 | |
1931 | : (HOST_WIDE_INT) (-1) << (precision - 1)), | |
1932 | (((HOST_WIDE_INT) (-1) | |
1933 | << (precision - HOST_BITS_PER_WIDE_INT - 1 > 0 | |
1934 | ? precision - HOST_BITS_PER_WIDE_INT - 1 | |
1935 | : 0)))); | |
7b6d72fc | 1936 | max_value |
7d60be94 NS |
1937 | = build_int_cst_wide (type, |
1938 | (precision - HOST_BITS_PER_WIDE_INT > 0 | |
1939 | ? -1 | |
1940 | : ((HOST_WIDE_INT) 1 << (precision - 1)) - 1), | |
1941 | (precision - HOST_BITS_PER_WIDE_INT - 1 > 0 | |
1942 | ? (((HOST_WIDE_INT) 1 | |
1943 | << (precision - HOST_BITS_PER_WIDE_INT - 1))) - 1 | |
1944 | : 0)); | |
7b6d72fc MM |
1945 | } |
1946 | ||
7b6d72fc MM |
1947 | TYPE_MIN_VALUE (type) = min_value; |
1948 | TYPE_MAX_VALUE (type) = max_value; | |
1949 | } | |
1950 | ||
4cc89e53 | 1951 | /* Set the extreme values of TYPE based on its precision in bits, |
13756074 | 1952 | then lay it out. Used when make_signed_type won't do |
4cc89e53 RS |
1953 | because the tree code is not INTEGER_TYPE. |
1954 | E.g. for Pascal, when the -fsigned-char option is given. */ | |
1955 | ||
1956 | void | |
46c5ad27 | 1957 | fixup_signed_type (tree type) |
4cc89e53 | 1958 | { |
b3694847 | 1959 | int precision = TYPE_PRECISION (type); |
4cc89e53 | 1960 | |
9cd56be1 JH |
1961 | /* We can not represent properly constants greater then |
1962 | 2 * HOST_BITS_PER_WIDE_INT, still we need the types | |
1963 | as they are used by i386 vector extensions and friends. */ | |
1964 | if (precision > HOST_BITS_PER_WIDE_INT * 2) | |
1965 | precision = HOST_BITS_PER_WIDE_INT * 2; | |
1966 | ||
f676971a | 1967 | set_min_and_max_values_for_integral_type (type, precision, |
7b6d72fc | 1968 | /*is_unsigned=*/false); |
4cc89e53 RS |
1969 | |
1970 | /* Lay out the type: set its alignment, size, etc. */ | |
4cc89e53 RS |
1971 | layout_type (type); |
1972 | } | |
1973 | ||
7306ed3f | 1974 | /* Set the extreme values of TYPE based on its precision in bits, |
13756074 | 1975 | then lay it out. This is used both in `make_unsigned_type' |
7306ed3f JW |
1976 | and for enumeral types. */ |
1977 | ||
1978 | void | |
46c5ad27 | 1979 | fixup_unsigned_type (tree type) |
7306ed3f | 1980 | { |
b3694847 | 1981 | int precision = TYPE_PRECISION (type); |
7306ed3f | 1982 | |
9cd56be1 JH |
1983 | /* We can not represent properly constants greater then |
1984 | 2 * HOST_BITS_PER_WIDE_INT, still we need the types | |
1985 | as they are used by i386 vector extensions and friends. */ | |
1986 | if (precision > HOST_BITS_PER_WIDE_INT * 2) | |
1987 | precision = HOST_BITS_PER_WIDE_INT * 2; | |
1988 | ||
89b0433e | 1989 | TYPE_UNSIGNED (type) = 1; |
f676971a EC |
1990 | |
1991 | set_min_and_max_values_for_integral_type (type, precision, | |
7b6d72fc | 1992 | /*is_unsigned=*/true); |
7306ed3f JW |
1993 | |
1994 | /* Lay out the type: set its alignment, size, etc. */ | |
7306ed3f JW |
1995 | layout_type (type); |
1996 | } | |
1997 | \f | |
1998 | /* Find the best machine mode to use when referencing a bit field of length | |
1999 | BITSIZE bits starting at BITPOS. | |
2000 | ||
2001 | The underlying object is known to be aligned to a boundary of ALIGN bits. | |
2002 | If LARGEST_MODE is not VOIDmode, it means that we should not use a mode | |
2003 | larger than LARGEST_MODE (usually SImode). | |
2004 | ||
2005 | If no mode meets all these conditions, we return VOIDmode. Otherwise, if | |
2006 | VOLATILEP is true or SLOW_BYTE_ACCESS is false, we return the smallest | |
2007 | mode meeting these conditions. | |
2008 | ||
77fa0940 RK |
2009 | Otherwise (VOLATILEP is false and SLOW_BYTE_ACCESS is true), we return |
2010 | the largest mode (but a mode no wider than UNITS_PER_WORD) that meets | |
2011 | all the conditions. */ | |
7306ed3f JW |
2012 | |
2013 | enum machine_mode | |
46c5ad27 AJ |
2014 | get_best_mode (int bitsize, int bitpos, unsigned int align, |
2015 | enum machine_mode largest_mode, int volatilep) | |
7306ed3f JW |
2016 | { |
2017 | enum machine_mode mode; | |
770ae6cc | 2018 | unsigned int unit = 0; |
7306ed3f JW |
2019 | |
2020 | /* Find the narrowest integer mode that contains the bit field. */ | |
2021 | for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode; | |
2022 | mode = GET_MODE_WIDER_MODE (mode)) | |
2023 | { | |
2024 | unit = GET_MODE_BITSIZE (mode); | |
956d6950 | 2025 | if ((bitpos % unit) + bitsize <= unit) |
7306ed3f JW |
2026 | break; |
2027 | } | |
2028 | ||
0c61f541 | 2029 | if (mode == VOIDmode |
7306ed3f | 2030 | /* It is tempting to omit the following line |
4e4b555d | 2031 | if STRICT_ALIGNMENT is true. |
7306ed3f JW |
2032 | But that is incorrect, since if the bitfield uses part of 3 bytes |
2033 | and we use a 4-byte mode, we could get a spurious segv | |
2034 | if the extra 4th byte is past the end of memory. | |
2035 | (Though at least one Unix compiler ignores this problem: | |
2036 | that on the Sequent 386 machine. */ | |
770ae6cc | 2037 | || MIN (unit, BIGGEST_ALIGNMENT) > align |
7306ed3f JW |
2038 | || (largest_mode != VOIDmode && unit > GET_MODE_BITSIZE (largest_mode))) |
2039 | return VOIDmode; | |
2040 | ||
77fa0940 RK |
2041 | if (SLOW_BYTE_ACCESS && ! volatilep) |
2042 | { | |
2043 | enum machine_mode wide_mode = VOIDmode, tmode; | |
2044 | ||
2045 | for (tmode = GET_CLASS_NARROWEST_MODE (MODE_INT); tmode != VOIDmode; | |
2046 | tmode = GET_MODE_WIDER_MODE (tmode)) | |
2047 | { | |
2048 | unit = GET_MODE_BITSIZE (tmode); | |
2049 | if (bitpos / unit == (bitpos + bitsize - 1) / unit | |
2050 | && unit <= BITS_PER_WORD | |
770ae6cc | 2051 | && unit <= MIN (align, BIGGEST_ALIGNMENT) |
77fa0940 RK |
2052 | && (largest_mode == VOIDmode |
2053 | || unit <= GET_MODE_BITSIZE (largest_mode))) | |
2054 | wide_mode = tmode; | |
2055 | } | |
2056 | ||
2057 | if (wide_mode != VOIDmode) | |
2058 | return wide_mode; | |
2059 | } | |
7306ed3f JW |
2060 | |
2061 | return mode; | |
2062 | } | |
d7db6646 | 2063 | |
50654f6c | 2064 | /* Gets minimal and maximal values for MODE (signed or unsigned depending on |
0aea6467 | 2065 | SIGN). The returned constants are made to be usable in TARGET_MODE. */ |
50654f6c ZD |
2066 | |
2067 | void | |
0aea6467 ZD |
2068 | get_mode_bounds (enum machine_mode mode, int sign, |
2069 | enum machine_mode target_mode, | |
2070 | rtx *mmin, rtx *mmax) | |
50654f6c | 2071 | { |
0aea6467 ZD |
2072 | unsigned size = GET_MODE_BITSIZE (mode); |
2073 | unsigned HOST_WIDE_INT min_val, max_val; | |
50654f6c | 2074 | |
41374e13 | 2075 | gcc_assert (size <= HOST_BITS_PER_WIDE_INT); |
50654f6c ZD |
2076 | |
2077 | if (sign) | |
2078 | { | |
0aea6467 ZD |
2079 | min_val = -((unsigned HOST_WIDE_INT) 1 << (size - 1)); |
2080 | max_val = ((unsigned HOST_WIDE_INT) 1 << (size - 1)) - 1; | |
50654f6c ZD |
2081 | } |
2082 | else | |
2083 | { | |
0aea6467 ZD |
2084 | min_val = 0; |
2085 | max_val = ((unsigned HOST_WIDE_INT) 1 << (size - 1) << 1) - 1; | |
50654f6c | 2086 | } |
0aea6467 | 2087 | |
bb80db7b KH |
2088 | *mmin = gen_int_mode (min_val, target_mode); |
2089 | *mmax = gen_int_mode (max_val, target_mode); | |
50654f6c ZD |
2090 | } |
2091 | ||
e2500fed | 2092 | #include "gt-stor-layout.h" |