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7306ed3f | 1 | /* C-compiler utilities for types and variables storage layout |
06ceef4e | 2 | Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1996, 1998, |
455f14dd | 3 | 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 |
71d59383 | 4 | Free Software Foundation, Inc. |
7306ed3f | 5 | |
1322177d | 6 | This file is part of GCC. |
7306ed3f | 7 | |
1322177d LB |
8 | GCC is free software; you can redistribute it and/or modify it under |
9 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 10 | Software Foundation; either version 3, or (at your option) any later |
1322177d | 11 | version. |
7306ed3f | 12 | |
1322177d LB |
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
7306ed3f JW |
17 | |
18 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
19 | along with GCC; see the file COPYING3. If not see |
20 | <http://www.gnu.org/licenses/>. */ | |
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" |
ea40ba9c | 33 | #include "output.h" |
10f0ad3d | 34 | #include "toplev.h" |
d7db6646 | 35 | #include "ggc.h" |
f913c102 | 36 | #include "target.h" |
43577e6b | 37 | #include "langhooks.h" |
26277d41 | 38 | #include "regs.h" |
89b0433e | 39 | #include "params.h" |
7306ed3f | 40 | |
7306ed3f | 41 | /* Data type for the expressions representing sizes of data types. |
896cced4 | 42 | It is the first integer type laid out. */ |
fed3cef0 | 43 | tree sizetype_tab[(int) TYPE_KIND_LAST]; |
7306ed3f | 44 | |
d4c40650 RS |
45 | /* If nonzero, this is an upper limit on alignment of structure fields. |
46 | The value is measured in bits. */ | |
467cecf3 | 47 | unsigned int maximum_field_alignment = TARGET_DEFAULT_PACK_STRUCT * BITS_PER_UNIT; |
8c27b7d4 | 48 | /* ... and its original value in bytes, specified via -fpack-struct=<value>. */ |
467cecf3 | 49 | unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT; |
d4c40650 | 50 | |
b5d6a2ff RK |
51 | /* Nonzero if all REFERENCE_TYPEs are internal and hence should be |
52 | allocated in Pmode, not ptr_mode. Set only by internal_reference_types | |
53 | called only by a front end. */ | |
54 | static int reference_types_internal = 0; | |
55 | ||
46c5ad27 AJ |
56 | static void finalize_record_size (record_layout_info); |
57 | static void finalize_type_size (tree); | |
58 | static void place_union_field (record_layout_info, tree); | |
b8089d8d | 59 | #if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED) |
46c5ad27 AJ |
60 | static int excess_unit_span (HOST_WIDE_INT, HOST_WIDE_INT, HOST_WIDE_INT, |
61 | HOST_WIDE_INT, tree); | |
b8089d8d | 62 | #endif |
46c5ad27 | 63 | extern void debug_rli (record_layout_info); |
7306ed3f JW |
64 | \f |
65 | /* SAVE_EXPRs for sizes of types and decls, waiting to be expanded. */ | |
66 | ||
e2500fed | 67 | static GTY(()) tree pending_sizes; |
7306ed3f | 68 | |
b5d6a2ff RK |
69 | /* Show that REFERENCE_TYPES are internal and should be Pmode. Called only |
70 | by front end. */ | |
71 | ||
72 | void | |
46c5ad27 | 73 | internal_reference_types (void) |
b5d6a2ff RK |
74 | { |
75 | reference_types_internal = 1; | |
76 | } | |
77 | ||
770ae6cc RK |
78 | /* Get a list of all the objects put on the pending sizes list. */ |
79 | ||
7306ed3f | 80 | tree |
46c5ad27 | 81 | get_pending_sizes (void) |
7306ed3f JW |
82 | { |
83 | tree chain = pending_sizes; | |
d4b60170 | 84 | |
7306ed3f JW |
85 | pending_sizes = 0; |
86 | return chain; | |
87 | } | |
88 | ||
fe375cf1 JJ |
89 | /* Add EXPR to the pending sizes list. */ |
90 | ||
91 | void | |
46c5ad27 | 92 | put_pending_size (tree expr) |
fe375cf1 | 93 | { |
3874585e RK |
94 | /* Strip any simple arithmetic from EXPR to see if it has an underlying |
95 | SAVE_EXPR. */ | |
a9ecacf6 | 96 | expr = skip_simple_arithmetic (expr); |
3874585e RK |
97 | |
98 | if (TREE_CODE (expr) == SAVE_EXPR) | |
99 | pending_sizes = tree_cons (NULL_TREE, expr, pending_sizes); | |
fe375cf1 JJ |
100 | } |
101 | ||
770ae6cc RK |
102 | /* Put a chain of objects into the pending sizes list, which must be |
103 | empty. */ | |
104 | ||
1fd7c4ac | 105 | void |
46c5ad27 | 106 | put_pending_sizes (tree chain) |
1fd7c4ac | 107 | { |
41374e13 | 108 | gcc_assert (!pending_sizes); |
1fd7c4ac RK |
109 | pending_sizes = chain; |
110 | } | |
111 | ||
76ffb3a0 | 112 | /* Given a size SIZE that may not be a constant, return a SAVE_EXPR |
7306ed3f JW |
113 | to serve as the actual size-expression for a type or decl. */ |
114 | ||
4e4b555d | 115 | tree |
46c5ad27 | 116 | variable_size (tree size) |
7306ed3f | 117 | { |
3695c25f JM |
118 | tree save; |
119 | ||
5e9bec99 RK |
120 | /* If the language-processor is to take responsibility for variable-sized |
121 | items (e.g., languages which have elaboration procedures like Ada), | |
ac79cd5a RK |
122 | just return SIZE unchanged. Likewise for self-referential sizes and |
123 | constant sizes. */ | |
76ffb3a0 | 124 | if (TREE_CONSTANT (size) |
ae2bcd98 | 125 | || lang_hooks.decls.global_bindings_p () < 0 |
679035f3 | 126 | || CONTAINS_PLACEHOLDER_P (size)) |
5e9bec99 RK |
127 | return size; |
128 | ||
ad50bc8d | 129 | size = save_expr (size); |
68de3831 | 130 | |
d26f8097 MM |
131 | /* If an array with a variable number of elements is declared, and |
132 | the elements require destruction, we will emit a cleanup for the | |
133 | array. That cleanup is run both on normal exit from the block | |
134 | and in the exception-handler for the block. Normally, when code | |
135 | is used in both ordinary code and in an exception handler it is | |
136 | `unsaved', i.e., all SAVE_EXPRs are recalculated. However, we do | |
137 | not wish to do that here; the array-size is the same in both | |
138 | places. */ | |
1c9766da | 139 | save = skip_simple_arithmetic (size); |
d26f8097 | 140 | |
6a0bec2c | 141 | if (cfun && cfun->x_dont_save_pending_sizes_p) |
6de9cd9a DN |
142 | /* The front-end doesn't want us to keep a list of the expressions |
143 | that determine sizes for variable size objects. Trust it. */ | |
144 | return size; | |
145 | ||
ae2bcd98 | 146 | if (lang_hooks.decls.global_bindings_p ()) |
7306ed3f | 147 | { |
80f9c711 | 148 | if (TREE_CONSTANT (size)) |
971801ff | 149 | error ("type size can%'t be explicitly evaluated"); |
80f9c711 RS |
150 | else |
151 | error ("variable-size type declared outside of any function"); | |
152 | ||
fed3cef0 | 153 | return size_one_node; |
7306ed3f JW |
154 | } |
155 | ||
6a0bec2c | 156 | put_pending_size (save); |
7306ed3f JW |
157 | |
158 | return size; | |
159 | } | |
160 | \f | |
161 | #ifndef MAX_FIXED_MODE_SIZE | |
162 | #define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (DImode) | |
163 | #endif | |
164 | ||
37783865 ZW |
165 | /* Return the machine mode to use for a nonscalar of SIZE bits. The |
166 | mode must be in class CLASS, and have exactly that many value bits; | |
167 | it may have padding as well. If LIMIT is nonzero, modes of wider | |
168 | than MAX_FIXED_MODE_SIZE will not be used. */ | |
7306ed3f JW |
169 | |
170 | enum machine_mode | |
46c5ad27 | 171 | mode_for_size (unsigned int size, enum mode_class class, int limit) |
7306ed3f | 172 | { |
b3694847 | 173 | enum machine_mode mode; |
7306ed3f | 174 | |
72c602fc | 175 | if (limit && size > MAX_FIXED_MODE_SIZE) |
7306ed3f JW |
176 | return BLKmode; |
177 | ||
5e9bec99 | 178 | /* Get the first mode which has this size, in the specified class. */ |
7306ed3f JW |
179 | for (mode = GET_CLASS_NARROWEST_MODE (class); mode != VOIDmode; |
180 | mode = GET_MODE_WIDER_MODE (mode)) | |
37783865 | 181 | if (GET_MODE_PRECISION (mode) == size) |
7306ed3f JW |
182 | return mode; |
183 | ||
184 | return BLKmode; | |
185 | } | |
186 | ||
72c602fc RK |
187 | /* Similar, except passed a tree node. */ |
188 | ||
189 | enum machine_mode | |
46c5ad27 | 190 | mode_for_size_tree (tree size, enum mode_class class, int limit) |
72c602fc | 191 | { |
a6a12bb9 RS |
192 | unsigned HOST_WIDE_INT uhwi; |
193 | unsigned int ui; | |
194 | ||
195 | if (!host_integerp (size, 1)) | |
72c602fc | 196 | return BLKmode; |
a6a12bb9 RS |
197 | uhwi = tree_low_cst (size, 1); |
198 | ui = uhwi; | |
199 | if (uhwi != ui) | |
200 | return BLKmode; | |
201 | return mode_for_size (ui, class, limit); | |
72c602fc RK |
202 | } |
203 | ||
5e9bec99 | 204 | /* Similar, but never return BLKmode; return the narrowest mode that |
37783865 | 205 | contains at least the requested number of value bits. */ |
5e9bec99 | 206 | |
27922c13 | 207 | enum machine_mode |
46c5ad27 | 208 | smallest_mode_for_size (unsigned int size, enum mode_class class) |
5e9bec99 | 209 | { |
b3694847 | 210 | enum machine_mode mode; |
5e9bec99 RK |
211 | |
212 | /* Get the first mode which has at least this size, in the | |
213 | specified class. */ | |
214 | for (mode = GET_CLASS_NARROWEST_MODE (class); mode != VOIDmode; | |
215 | mode = GET_MODE_WIDER_MODE (mode)) | |
37783865 | 216 | if (GET_MODE_PRECISION (mode) >= size) |
5e9bec99 RK |
217 | return mode; |
218 | ||
41374e13 | 219 | gcc_unreachable (); |
5e9bec99 RK |
220 | } |
221 | ||
d006aa54 RH |
222 | /* Find an integer mode of the exact same size, or BLKmode on failure. */ |
223 | ||
224 | enum machine_mode | |
46c5ad27 | 225 | int_mode_for_mode (enum machine_mode mode) |
d006aa54 RH |
226 | { |
227 | switch (GET_MODE_CLASS (mode)) | |
228 | { | |
229 | case MODE_INT: | |
230 | case MODE_PARTIAL_INT: | |
231 | break; | |
232 | ||
233 | case MODE_COMPLEX_INT: | |
234 | case MODE_COMPLEX_FLOAT: | |
235 | case MODE_FLOAT: | |
15ed7b52 | 236 | case MODE_DECIMAL_FLOAT: |
62c07905 JM |
237 | case MODE_VECTOR_INT: |
238 | case MODE_VECTOR_FLOAT: | |
d006aa54 RH |
239 | mode = mode_for_size (GET_MODE_BITSIZE (mode), MODE_INT, 0); |
240 | break; | |
241 | ||
242 | case MODE_RANDOM: | |
243 | if (mode == BLKmode) | |
786de7eb | 244 | break; |
d4b60170 | 245 | |
2d76cb1a | 246 | /* ... fall through ... */ |
d006aa54 RH |
247 | |
248 | case MODE_CC: | |
249 | default: | |
41374e13 | 250 | gcc_unreachable (); |
d006aa54 RH |
251 | } |
252 | ||
253 | return mode; | |
254 | } | |
255 | ||
187515f5 AO |
256 | /* Return the alignment of MODE. This will be bounded by 1 and |
257 | BIGGEST_ALIGNMENT. */ | |
258 | ||
259 | unsigned int | |
46c5ad27 | 260 | get_mode_alignment (enum machine_mode mode) |
187515f5 | 261 | { |
0974c7d7 | 262 | return MIN (BIGGEST_ALIGNMENT, MAX (1, mode_base_align[mode]*BITS_PER_UNIT)); |
187515f5 AO |
263 | } |
264 | ||
7306ed3f | 265 | \f |
78d55cc8 JM |
266 | /* Subroutine of layout_decl: Force alignment required for the data type. |
267 | But if the decl itself wants greater alignment, don't override that. */ | |
268 | ||
269 | static inline void | |
270 | do_type_align (tree type, tree decl) | |
271 | { | |
272 | if (TYPE_ALIGN (type) > DECL_ALIGN (decl)) | |
273 | { | |
274 | DECL_ALIGN (decl) = TYPE_ALIGN (type); | |
3acef2ae JM |
275 | if (TREE_CODE (decl) == FIELD_DECL) |
276 | DECL_USER_ALIGN (decl) = TYPE_USER_ALIGN (type); | |
78d55cc8 JM |
277 | } |
278 | } | |
279 | ||
7306ed3f JW |
280 | /* Set the size, mode and alignment of a ..._DECL node. |
281 | TYPE_DECL does need this for C++. | |
282 | Note that LABEL_DECL and CONST_DECL nodes do not need this, | |
283 | and FUNCTION_DECL nodes have them set up in a special (and simple) way. | |
284 | Don't call layout_decl for them. | |
285 | ||
286 | KNOWN_ALIGN is the amount of alignment we can assume this | |
287 | decl has with no special effort. It is relevant only for FIELD_DECLs | |
288 | and depends on the previous fields. | |
289 | All that matters about KNOWN_ALIGN is which powers of 2 divide it. | |
290 | If KNOWN_ALIGN is 0, it means, "as much alignment as you like": | |
291 | the record will be aligned to suit. */ | |
292 | ||
293 | void | |
46c5ad27 | 294 | layout_decl (tree decl, unsigned int known_align) |
7306ed3f | 295 | { |
b3694847 SS |
296 | tree type = TREE_TYPE (decl); |
297 | enum tree_code code = TREE_CODE (decl); | |
a46666a9 | 298 | rtx rtl = NULL_RTX; |
7306ed3f JW |
299 | |
300 | if (code == CONST_DECL) | |
301 | return; | |
0ac11108 | 302 | |
41374e13 NS |
303 | gcc_assert (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL |
304 | || code == TYPE_DECL ||code == FIELD_DECL); | |
0ac11108 | 305 | |
a46666a9 RH |
306 | rtl = DECL_RTL_IF_SET (decl); |
307 | ||
7306ed3f | 308 | if (type == error_mark_node) |
33433751 | 309 | type = void_type_node; |
7306ed3f | 310 | |
770ae6cc RK |
311 | /* Usually the size and mode come from the data type without change, |
312 | however, the front-end may set the explicit width of the field, so its | |
313 | size may not be the same as the size of its type. This happens with | |
314 | bitfields, of course (an `int' bitfield may be only 2 bits, say), but it | |
315 | also happens with other fields. For example, the C++ front-end creates | |
316 | zero-sized fields corresponding to empty base classes, and depends on | |
317 | layout_type setting DECL_FIELD_BITPOS correctly for the field. Set the | |
4b6bf620 RK |
318 | size in bytes from the size in bits. If we have already set the mode, |
319 | don't set it again since we can be called twice for FIELD_DECLs. */ | |
770ae6cc | 320 | |
a150de29 | 321 | DECL_UNSIGNED (decl) = TYPE_UNSIGNED (type); |
4b6bf620 RK |
322 | if (DECL_MODE (decl) == VOIDmode) |
323 | DECL_MODE (decl) = TYPE_MODE (type); | |
770ae6cc | 324 | |
5e9bec99 | 325 | if (DECL_SIZE (decl) == 0) |
06ceef4e | 326 | { |
ad50bc8d RH |
327 | DECL_SIZE (decl) = TYPE_SIZE (type); |
328 | DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (type); | |
06ceef4e | 329 | } |
1a96dc46 | 330 | else if (DECL_SIZE_UNIT (decl) == 0) |
770ae6cc | 331 | DECL_SIZE_UNIT (decl) |
455f19cb MM |
332 | = fold_convert (sizetype, size_binop (CEIL_DIV_EXPR, DECL_SIZE (decl), |
333 | bitsize_unit_node)); | |
06ceef4e | 334 | |
78d55cc8 JM |
335 | if (code != FIELD_DECL) |
336 | /* For non-fields, update the alignment from the type. */ | |
337 | do_type_align (type, decl); | |
338 | else | |
339 | /* For fields, it's a bit more complicated... */ | |
786de7eb | 340 | { |
40aae178 | 341 | bool old_user_align = DECL_USER_ALIGN (decl); |
d1a701eb MM |
342 | bool zero_bitfield = false; |
343 | bool packed_p = DECL_PACKED (decl); | |
344 | unsigned int mfa; | |
40aae178 | 345 | |
78d55cc8 JM |
346 | if (DECL_BIT_FIELD (decl)) |
347 | { | |
348 | DECL_BIT_FIELD_TYPE (decl) = type; | |
7306ed3f | 349 | |
78d55cc8 | 350 | /* A zero-length bit-field affects the alignment of the next |
d1a701eb MM |
351 | field. In essence such bit-fields are not influenced by |
352 | any packing due to #pragma pack or attribute packed. */ | |
78d55cc8 | 353 | if (integer_zerop (DECL_SIZE (decl)) |
5fd9b178 | 354 | && ! targetm.ms_bitfield_layout_p (DECL_FIELD_CONTEXT (decl))) |
78d55cc8 | 355 | { |
d1a701eb MM |
356 | zero_bitfield = true; |
357 | packed_p = false; | |
78d55cc8 JM |
358 | #ifdef PCC_BITFIELD_TYPE_MATTERS |
359 | if (PCC_BITFIELD_TYPE_MATTERS) | |
360 | do_type_align (type, decl); | |
361 | else | |
362 | #endif | |
ad3f5759 | 363 | { |
78d55cc8 | 364 | #ifdef EMPTY_FIELD_BOUNDARY |
ad3f5759 AS |
365 | if (EMPTY_FIELD_BOUNDARY > DECL_ALIGN (decl)) |
366 | { | |
367 | DECL_ALIGN (decl) = EMPTY_FIELD_BOUNDARY; | |
368 | DECL_USER_ALIGN (decl) = 0; | |
369 | } | |
78d55cc8 | 370 | #endif |
ad3f5759 | 371 | } |
78d55cc8 JM |
372 | } |
373 | ||
374 | /* See if we can use an ordinary integer mode for a bit-field. | |
375 | Conditions are: a fixed size that is correct for another mode | |
376 | and occupying a complete byte or bytes on proper boundary. */ | |
377 | if (TYPE_SIZE (type) != 0 | |
378 | && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST | |
379 | && GET_MODE_CLASS (TYPE_MODE (type)) == MODE_INT) | |
380 | { | |
381 | enum machine_mode xmode | |
382 | = mode_for_size_tree (DECL_SIZE (decl), MODE_INT, 1); | |
383 | ||
f676971a | 384 | if (xmode != BLKmode |
9a706ec7 MM |
385 | && (known_align == 0 |
386 | || known_align >= GET_MODE_ALIGNMENT (xmode))) | |
78d55cc8 JM |
387 | { |
388 | DECL_ALIGN (decl) = MAX (GET_MODE_ALIGNMENT (xmode), | |
389 | DECL_ALIGN (decl)); | |
390 | DECL_MODE (decl) = xmode; | |
391 | DECL_BIT_FIELD (decl) = 0; | |
392 | } | |
393 | } | |
394 | ||
395 | /* Turn off DECL_BIT_FIELD if we won't need it set. */ | |
396 | if (TYPE_MODE (type) == BLKmode && DECL_MODE (decl) == BLKmode | |
397 | && known_align >= TYPE_ALIGN (type) | |
398 | && DECL_ALIGN (decl) >= TYPE_ALIGN (type)) | |
399 | DECL_BIT_FIELD (decl) = 0; | |
400 | } | |
d1a701eb | 401 | else if (packed_p && DECL_USER_ALIGN (decl)) |
78d55cc8 | 402 | /* Don't touch DECL_ALIGN. For other packed fields, go ahead and |
2038bd69 | 403 | round up; we'll reduce it again below. We want packing to |
ba228239 | 404 | supersede USER_ALIGN inherited from the type, but defer to |
2038bd69 | 405 | alignment explicitly specified on the field decl. */; |
78d55cc8 | 406 | else |
40aae178 JM |
407 | do_type_align (type, decl); |
408 | ||
409 | /* If the field is of variable size, we can't misalign it since we | |
410 | have no way to make a temporary to align the result. But this | |
411 | isn't an issue if the decl is not addressable. Likewise if it | |
412 | is of unknown size. | |
413 | ||
414 | Note that do_type_align may set DECL_USER_ALIGN, so we need to | |
415 | check old_user_align instead. */ | |
d1a701eb | 416 | if (packed_p |
40aae178 JM |
417 | && !old_user_align |
418 | && (DECL_NONADDRESSABLE_P (decl) | |
419 | || DECL_SIZE_UNIT (decl) == 0 | |
420 | || TREE_CODE (DECL_SIZE_UNIT (decl)) == INTEGER_CST)) | |
421 | DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), BITS_PER_UNIT); | |
78d55cc8 | 422 | |
d1a701eb | 423 | if (! packed_p && ! DECL_USER_ALIGN (decl)) |
7306ed3f | 424 | { |
78d55cc8 JM |
425 | /* Some targets (i.e. i386, VMS) limit struct field alignment |
426 | to a lower boundary than alignment of variables unless | |
427 | it was overridden by attribute aligned. */ | |
428 | #ifdef BIGGEST_FIELD_ALIGNMENT | |
429 | DECL_ALIGN (decl) | |
430 | = MIN (DECL_ALIGN (decl), (unsigned) BIGGEST_FIELD_ALIGNMENT); | |
431 | #endif | |
432 | #ifdef ADJUST_FIELD_ALIGN | |
433 | DECL_ALIGN (decl) = ADJUST_FIELD_ALIGN (decl, DECL_ALIGN (decl)); | |
434 | #endif | |
7306ed3f | 435 | } |
9ca75f15 | 436 | |
d1a701eb MM |
437 | if (zero_bitfield) |
438 | mfa = initial_max_fld_align * BITS_PER_UNIT; | |
439 | else | |
440 | mfa = maximum_field_alignment; | |
9ca75f15 | 441 | /* Should this be controlled by DECL_USER_ALIGN, too? */ |
d1a701eb MM |
442 | if (mfa != 0) |
443 | DECL_ALIGN (decl) = MIN (DECL_ALIGN (decl), mfa); | |
7306ed3f JW |
444 | } |
445 | ||
446 | /* Evaluate nonconstant size only once, either now or as soon as safe. */ | |
447 | if (DECL_SIZE (decl) != 0 && TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST) | |
448 | DECL_SIZE (decl) = variable_size (DECL_SIZE (decl)); | |
06ceef4e RK |
449 | if (DECL_SIZE_UNIT (decl) != 0 |
450 | && TREE_CODE (DECL_SIZE_UNIT (decl)) != INTEGER_CST) | |
451 | DECL_SIZE_UNIT (decl) = variable_size (DECL_SIZE_UNIT (decl)); | |
452 | ||
453 | /* If requested, warn about definitions of large data objects. */ | |
454 | if (warn_larger_than | |
17aec3eb | 455 | && (code == VAR_DECL || code == PARM_DECL) |
06ceef4e RK |
456 | && ! DECL_EXTERNAL (decl)) |
457 | { | |
458 | tree size = DECL_SIZE_UNIT (decl); | |
459 | ||
460 | if (size != 0 && TREE_CODE (size) == INTEGER_CST | |
05bccae2 | 461 | && compare_tree_int (size, larger_than_size) > 0) |
06ceef4e | 462 | { |
0384674e | 463 | int size_as_int = TREE_INT_CST_LOW (size); |
06ceef4e | 464 | |
05bccae2 | 465 | if (compare_tree_int (size, size_as_int) == 0) |
dee15844 | 466 | warning (0, "size of %q+D is %d bytes", decl, size_as_int); |
06ceef4e | 467 | else |
ea40ba9c | 468 | warning (0, "size of %q+D is larger than %wd bytes", |
dee15844 | 469 | decl, larger_than_size); |
06ceef4e RK |
470 | } |
471 | } | |
a46666a9 RH |
472 | |
473 | /* If the RTL was already set, update its mode and mem attributes. */ | |
474 | if (rtl) | |
475 | { | |
476 | PUT_MODE (rtl, DECL_MODE (decl)); | |
477 | SET_DECL_RTL (decl, 0); | |
478 | set_mem_attributes (rtl, decl, 1); | |
479 | SET_DECL_RTL (decl, rtl); | |
480 | } | |
7306ed3f | 481 | } |
d8472c75 JM |
482 | |
483 | /* Given a VAR_DECL, PARM_DECL or RESULT_DECL, clears the results of | |
484 | a previous call to layout_decl and calls it again. */ | |
485 | ||
486 | void | |
487 | relayout_decl (tree decl) | |
488 | { | |
489 | DECL_SIZE (decl) = DECL_SIZE_UNIT (decl) = 0; | |
490 | DECL_MODE (decl) = VOIDmode; | |
c9eee440 AP |
491 | if (!DECL_USER_ALIGN (decl)) |
492 | DECL_ALIGN (decl) = 0; | |
d8472c75 JM |
493 | SET_DECL_RTL (decl, 0); |
494 | ||
495 | layout_decl (decl, 0); | |
496 | } | |
7306ed3f | 497 | \f |
e0cea8d9 RK |
498 | /* Hook for a front-end function that can modify the record layout as needed |
499 | immediately before it is finalized. */ | |
500 | ||
1bb11558 | 501 | static void (*lang_adjust_rli) (record_layout_info) = 0; |
e0cea8d9 RK |
502 | |
503 | void | |
46c5ad27 | 504 | set_lang_adjust_rli (void (*f) (record_layout_info)) |
e0cea8d9 RK |
505 | { |
506 | lang_adjust_rli = f; | |
507 | } | |
508 | ||
770ae6cc RK |
509 | /* Begin laying out type T, which may be a RECORD_TYPE, UNION_TYPE, or |
510 | QUAL_UNION_TYPE. Return a pointer to a struct record_layout_info which | |
511 | is to be passed to all other layout functions for this record. It is the | |
786de7eb | 512 | responsibility of the caller to call `free' for the storage returned. |
770ae6cc RK |
513 | Note that garbage collection is not permitted until we finish laying |
514 | out the record. */ | |
7306ed3f | 515 | |
9328904c | 516 | record_layout_info |
46c5ad27 | 517 | start_record_layout (tree t) |
7306ed3f | 518 | { |
703ad42b | 519 | record_layout_info rli = xmalloc (sizeof (struct record_layout_info_s)); |
9328904c MM |
520 | |
521 | rli->t = t; | |
770ae6cc | 522 | |
9328904c MM |
523 | /* If the type has a minimum specified alignment (via an attribute |
524 | declaration, for example) use it -- otherwise, start with a | |
525 | one-byte alignment. */ | |
526 | rli->record_align = MAX (BITS_PER_UNIT, TYPE_ALIGN (t)); | |
78d55cc8 | 527 | rli->unpacked_align = rli->record_align; |
770ae6cc | 528 | rli->offset_align = MAX (rli->record_align, BIGGEST_ALIGNMENT); |
7306ed3f | 529 | |
5c19a356 MS |
530 | #ifdef STRUCTURE_SIZE_BOUNDARY |
531 | /* Packed structures don't need to have minimum size. */ | |
f132af85 | 532 | if (! TYPE_PACKED (t)) |
353293e7 PB |
533 | { |
534 | unsigned tmp; | |
535 | ||
536 | /* #pragma pack overrides STRUCTURE_SIZE_BOUNDARY. */ | |
537 | tmp = (unsigned) STRUCTURE_SIZE_BOUNDARY; | |
538 | if (maximum_field_alignment != 0) | |
539 | tmp = MIN (tmp, maximum_field_alignment); | |
540 | rli->record_align = MAX (rli->record_align, tmp); | |
541 | } | |
5c19a356 | 542 | #endif |
7306ed3f | 543 | |
770ae6cc RK |
544 | rli->offset = size_zero_node; |
545 | rli->bitpos = bitsize_zero_node; | |
f913c102 | 546 | rli->prev_field = 0; |
770ae6cc RK |
547 | rli->pending_statics = 0; |
548 | rli->packed_maybe_necessary = 0; | |
0ac11108 | 549 | rli->remaining_in_alignment = 0; |
770ae6cc | 550 | |
9328904c MM |
551 | return rli; |
552 | } | |
7306ed3f | 553 | |
f2704b9f RK |
554 | /* These four routines perform computations that convert between |
555 | the offset/bitpos forms and byte and bit offsets. */ | |
556 | ||
557 | tree | |
46c5ad27 | 558 | bit_from_pos (tree offset, tree bitpos) |
f2704b9f RK |
559 | { |
560 | return size_binop (PLUS_EXPR, bitpos, | |
0ac11108 | 561 | size_binop (MULT_EXPR, |
455f19cb | 562 | fold_convert (bitsizetype, offset), |
f2704b9f RK |
563 | bitsize_unit_node)); |
564 | } | |
565 | ||
566 | tree | |
46c5ad27 | 567 | byte_from_pos (tree offset, tree bitpos) |
f2704b9f RK |
568 | { |
569 | return size_binop (PLUS_EXPR, offset, | |
455f19cb MM |
570 | fold_convert (sizetype, |
571 | size_binop (TRUNC_DIV_EXPR, bitpos, | |
572 | bitsize_unit_node))); | |
f2704b9f RK |
573 | } |
574 | ||
f2704b9f | 575 | void |
46c5ad27 AJ |
576 | pos_from_bit (tree *poffset, tree *pbitpos, unsigned int off_align, |
577 | tree pos) | |
f2704b9f RK |
578 | { |
579 | *poffset = size_binop (MULT_EXPR, | |
455f19cb MM |
580 | fold_convert (sizetype, |
581 | size_binop (FLOOR_DIV_EXPR, pos, | |
582 | bitsize_int (off_align))), | |
f2704b9f RK |
583 | size_int (off_align / BITS_PER_UNIT)); |
584 | *pbitpos = size_binop (FLOOR_MOD_EXPR, pos, bitsize_int (off_align)); | |
585 | } | |
586 | ||
587 | /* Given a pointer to bit and byte offsets and an offset alignment, | |
588 | normalize the offsets so they are within the alignment. */ | |
589 | ||
590 | void | |
46c5ad27 | 591 | normalize_offset (tree *poffset, tree *pbitpos, unsigned int off_align) |
f2704b9f RK |
592 | { |
593 | /* If the bit position is now larger than it should be, adjust it | |
594 | downwards. */ | |
595 | if (compare_tree_int (*pbitpos, off_align) >= 0) | |
596 | { | |
597 | tree extra_aligns = size_binop (FLOOR_DIV_EXPR, *pbitpos, | |
598 | bitsize_int (off_align)); | |
599 | ||
600 | *poffset | |
601 | = size_binop (PLUS_EXPR, *poffset, | |
0ac11108 | 602 | size_binop (MULT_EXPR, |
455f19cb | 603 | fold_convert (sizetype, extra_aligns), |
f2704b9f | 604 | size_int (off_align / BITS_PER_UNIT))); |
786de7eb | 605 | |
f2704b9f RK |
606 | *pbitpos |
607 | = size_binop (FLOOR_MOD_EXPR, *pbitpos, bitsize_int (off_align)); | |
608 | } | |
609 | } | |
610 | ||
770ae6cc | 611 | /* Print debugging information about the information in RLI. */ |
cc9d4a85 | 612 | |
770ae6cc | 613 | void |
46c5ad27 | 614 | debug_rli (record_layout_info rli) |
cc9d4a85 | 615 | { |
770ae6cc RK |
616 | print_node_brief (stderr, "type", rli->t, 0); |
617 | print_node_brief (stderr, "\noffset", rli->offset, 0); | |
618 | print_node_brief (stderr, " bitpos", rli->bitpos, 0); | |
cc9d4a85 | 619 | |
78d55cc8 JM |
620 | fprintf (stderr, "\naligns: rec = %u, unpack = %u, off = %u\n", |
621 | rli->record_align, rli->unpacked_align, | |
e0cea8d9 | 622 | rli->offset_align); |
0ac11108 EC |
623 | |
624 | /* The ms_struct code is the only that uses this. */ | |
625 | if (targetm.ms_bitfield_layout_p (rli->t)) | |
0c397f9c | 626 | fprintf (stderr, "remaining in alignment = %u\n", rli->remaining_in_alignment); |
0ac11108 | 627 | |
770ae6cc RK |
628 | if (rli->packed_maybe_necessary) |
629 | fprintf (stderr, "packed may be necessary\n"); | |
630 | ||
631 | if (rli->pending_statics) | |
632 | { | |
633 | fprintf (stderr, "pending statics:\n"); | |
634 | debug_tree (rli->pending_statics); | |
635 | } | |
636 | } | |
637 | ||
638 | /* Given an RLI with a possibly-incremented BITPOS, adjust OFFSET and | |
639 | BITPOS if necessary to keep BITPOS below OFFSET_ALIGN. */ | |
640 | ||
641 | void | |
46c5ad27 | 642 | normalize_rli (record_layout_info rli) |
770ae6cc | 643 | { |
f2704b9f | 644 | normalize_offset (&rli->offset, &rli->bitpos, rli->offset_align); |
770ae6cc | 645 | } |
cc9d4a85 | 646 | |
770ae6cc RK |
647 | /* Returns the size in bytes allocated so far. */ |
648 | ||
649 | tree | |
46c5ad27 | 650 | rli_size_unit_so_far (record_layout_info rli) |
770ae6cc | 651 | { |
f2704b9f | 652 | return byte_from_pos (rli->offset, rli->bitpos); |
770ae6cc RK |
653 | } |
654 | ||
655 | /* Returns the size in bits allocated so far. */ | |
656 | ||
657 | tree | |
46c5ad27 | 658 | rli_size_so_far (record_layout_info rli) |
770ae6cc | 659 | { |
f2704b9f | 660 | return bit_from_pos (rli->offset, rli->bitpos); |
770ae6cc RK |
661 | } |
662 | ||
0645ba8f | 663 | /* FIELD is about to be added to RLI->T. The alignment (in bits) of |
cbbaf4ae R |
664 | the next available location within the record is given by KNOWN_ALIGN. |
665 | Update the variable alignment fields in RLI, and return the alignment | |
666 | to give the FIELD. */ | |
770ae6cc | 667 | |
6de9cd9a | 668 | unsigned int |
46c5ad27 AJ |
669 | update_alignment_for_field (record_layout_info rli, tree field, |
670 | unsigned int known_align) | |
9328904c MM |
671 | { |
672 | /* The alignment required for FIELD. */ | |
673 | unsigned int desired_align; | |
9328904c MM |
674 | /* The type of this field. */ |
675 | tree type = TREE_TYPE (field); | |
0645ba8f MM |
676 | /* True if the field was explicitly aligned by the user. */ |
677 | bool user_align; | |
78d55cc8 | 678 | bool is_bitfield; |
9328904c | 679 | |
9dfb66b9 CD |
680 | /* Do not attempt to align an ERROR_MARK node */ |
681 | if (TREE_CODE (type) == ERROR_MARK) | |
682 | return 0; | |
683 | ||
78d55cc8 JM |
684 | /* Lay out the field so we know what alignment it needs. */ |
685 | layout_decl (field, known_align); | |
770ae6cc | 686 | desired_align = DECL_ALIGN (field); |
11cf4d18 | 687 | user_align = DECL_USER_ALIGN (field); |
770ae6cc | 688 | |
78d55cc8 JM |
689 | is_bitfield = (type != error_mark_node |
690 | && DECL_BIT_FIELD_TYPE (field) | |
691 | && ! integer_zerop (TYPE_SIZE (type))); | |
7306ed3f | 692 | |
9328904c MM |
693 | /* Record must have at least as much alignment as any field. |
694 | Otherwise, the alignment of the field within the record is | |
695 | meaningless. */ | |
0ac11108 | 696 | if (targetm.ms_bitfield_layout_p (rli->t)) |
f913c102 | 697 | { |
e4850f36 DR |
698 | /* Here, the alignment of the underlying type of a bitfield can |
699 | affect the alignment of a record; even a zero-sized field | |
700 | can do this. The alignment should be to the alignment of | |
701 | the type, except that for zero-size bitfields this only | |
0e9e1e0a | 702 | applies if there was an immediately prior, nonzero-size |
e4850f36 | 703 | bitfield. (That's the way it is, experimentally.) */ |
cb312376 | 704 | if ((!is_bitfield && !DECL_PACKED (field)) |
0ac11108 EC |
705 | || (!integer_zerop (DECL_SIZE (field)) |
706 | ? !DECL_PACKED (field) | |
707 | : (rli->prev_field | |
708 | && DECL_BIT_FIELD_TYPE (rli->prev_field) | |
709 | && ! integer_zerop (DECL_SIZE (rli->prev_field))))) | |
f913c102 | 710 | { |
e4850f36 DR |
711 | unsigned int type_align = TYPE_ALIGN (type); |
712 | type_align = MAX (type_align, desired_align); | |
713 | if (maximum_field_alignment != 0) | |
714 | type_align = MIN (type_align, maximum_field_alignment); | |
715 | rli->record_align = MAX (rli->record_align, type_align); | |
f913c102 AO |
716 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
717 | } | |
786de7eb | 718 | } |
3c12fcc2 | 719 | #ifdef PCC_BITFIELD_TYPE_MATTERS |
78d55cc8 | 720 | else if (is_bitfield && PCC_BITFIELD_TYPE_MATTERS) |
9328904c | 721 | { |
8dc65b6e | 722 | /* Named bit-fields cause the entire structure to have the |
13c1cd82 PB |
723 | alignment implied by their type. Some targets also apply the same |
724 | rules to unnamed bitfields. */ | |
725 | if (DECL_NAME (field) != 0 | |
726 | || targetm.align_anon_bitfield ()) | |
7306ed3f | 727 | { |
9328904c | 728 | unsigned int type_align = TYPE_ALIGN (type); |
729a2125 | 729 | |
ad9335eb JJ |
730 | #ifdef ADJUST_FIELD_ALIGN |
731 | if (! TYPE_USER_ALIGN (type)) | |
732 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
733 | #endif | |
734 | ||
d1a701eb MM |
735 | /* Targets might chose to handle unnamed and hence possibly |
736 | zero-width bitfield. Those are not influenced by #pragmas | |
737 | or packed attributes. */ | |
738 | if (integer_zerop (DECL_SIZE (field))) | |
739 | { | |
740 | if (initial_max_fld_align) | |
741 | type_align = MIN (type_align, | |
742 | initial_max_fld_align * BITS_PER_UNIT); | |
743 | } | |
744 | else if (maximum_field_alignment != 0) | |
9328904c MM |
745 | type_align = MIN (type_align, maximum_field_alignment); |
746 | else if (DECL_PACKED (field)) | |
747 | type_align = MIN (type_align, BITS_PER_UNIT); | |
e2301a83 | 748 | |
8dc65b6e MM |
749 | /* The alignment of the record is increased to the maximum |
750 | of the current alignment, the alignment indicated on the | |
751 | field (i.e., the alignment specified by an __aligned__ | |
752 | attribute), and the alignment indicated by the type of | |
753 | the field. */ | |
754 | rli->record_align = MAX (rli->record_align, desired_align); | |
9328904c | 755 | rli->record_align = MAX (rli->record_align, type_align); |
8dc65b6e | 756 | |
3c12fcc2 | 757 | if (warn_packed) |
e0cea8d9 | 758 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
daf06049 | 759 | user_align |= TYPE_USER_ALIGN (type); |
3c12fcc2 | 760 | } |
9328904c | 761 | } |
9328904c | 762 | #endif |
78d55cc8 | 763 | else |
9328904c MM |
764 | { |
765 | rli->record_align = MAX (rli->record_align, desired_align); | |
770ae6cc | 766 | rli->unpacked_align = MAX (rli->unpacked_align, TYPE_ALIGN (type)); |
9328904c | 767 | } |
3c12fcc2 | 768 | |
0645ba8f MM |
769 | TYPE_USER_ALIGN (rli->t) |= user_align; |
770 | ||
771 | return desired_align; | |
772 | } | |
773 | ||
774 | /* Called from place_field to handle unions. */ | |
775 | ||
776 | static void | |
46c5ad27 | 777 | place_union_field (record_layout_info rli, tree field) |
0645ba8f MM |
778 | { |
779 | update_alignment_for_field (rli, field, /*known_align=*/0); | |
780 | ||
781 | DECL_FIELD_OFFSET (field) = size_zero_node; | |
782 | DECL_FIELD_BIT_OFFSET (field) = bitsize_zero_node; | |
783 | SET_DECL_OFFSET_ALIGN (field, BIGGEST_ALIGNMENT); | |
784 | ||
0ac11108 | 785 | /* If this is an ERROR_MARK return *after* having set the |
9dfb66b9 CD |
786 | field at the start of the union. This helps when parsing |
787 | invalid fields. */ | |
788 | if (TREE_CODE (TREE_TYPE (field)) == ERROR_MARK) | |
789 | return; | |
790 | ||
0645ba8f MM |
791 | /* We assume the union's size will be a multiple of a byte so we don't |
792 | bother with BITPOS. */ | |
793 | if (TREE_CODE (rli->t) == UNION_TYPE) | |
794 | rli->offset = size_binop (MAX_EXPR, rli->offset, DECL_SIZE_UNIT (field)); | |
795 | else if (TREE_CODE (rli->t) == QUAL_UNION_TYPE) | |
4845b383 KH |
796 | rli->offset = fold_build3 (COND_EXPR, sizetype, |
797 | DECL_QUALIFIER (field), | |
798 | DECL_SIZE_UNIT (field), rli->offset); | |
0645ba8f MM |
799 | } |
800 | ||
b8089d8d | 801 | #if defined (PCC_BITFIELD_TYPE_MATTERS) || defined (BITFIELD_NBYTES_LIMITED) |
4977bab6 | 802 | /* A bitfield of SIZE with a required access alignment of ALIGN is allocated |
272d0bee | 803 | at BYTE_OFFSET / BIT_OFFSET. Return nonzero if the field would span more |
4977bab6 ZW |
804 | units of alignment than the underlying TYPE. */ |
805 | static int | |
46c5ad27 AJ |
806 | excess_unit_span (HOST_WIDE_INT byte_offset, HOST_WIDE_INT bit_offset, |
807 | HOST_WIDE_INT size, HOST_WIDE_INT align, tree type) | |
4977bab6 ZW |
808 | { |
809 | /* Note that the calculation of OFFSET might overflow; we calculate it so | |
810 | that we still get the right result as long as ALIGN is a power of two. */ | |
811 | unsigned HOST_WIDE_INT offset = byte_offset * BITS_PER_UNIT + bit_offset; | |
812 | ||
813 | offset = offset % align; | |
814 | return ((offset + size + align - 1) / align | |
815 | > ((unsigned HOST_WIDE_INT) tree_low_cst (TYPE_SIZE (type), 1) | |
816 | / align)); | |
817 | } | |
b8089d8d | 818 | #endif |
4977bab6 | 819 | |
0645ba8f MM |
820 | /* RLI contains information about the layout of a RECORD_TYPE. FIELD |
821 | is a FIELD_DECL to be added after those fields already present in | |
822 | T. (FIELD is not actually added to the TYPE_FIELDS list here; | |
823 | callers that desire that behavior must manually perform that step.) */ | |
824 | ||
825 | void | |
46c5ad27 | 826 | place_field (record_layout_info rli, tree field) |
0645ba8f MM |
827 | { |
828 | /* The alignment required for FIELD. */ | |
829 | unsigned int desired_align; | |
830 | /* The alignment FIELD would have if we just dropped it into the | |
831 | record as it presently stands. */ | |
832 | unsigned int known_align; | |
833 | unsigned int actual_align; | |
834 | /* The type of this field. */ | |
835 | tree type = TREE_TYPE (field); | |
836 | ||
dbe91deb | 837 | gcc_assert (TREE_CODE (field) != ERROR_MARK); |
0645ba8f MM |
838 | |
839 | /* If FIELD is static, then treat it like a separate variable, not | |
840 | really like a structure field. If it is a FUNCTION_DECL, it's a | |
841 | method. In both cases, all we do is lay out the decl, and we do | |
842 | it *after* the record is laid out. */ | |
843 | if (TREE_CODE (field) == VAR_DECL) | |
844 | { | |
845 | rli->pending_statics = tree_cons (NULL_TREE, field, | |
846 | rli->pending_statics); | |
847 | return; | |
848 | } | |
849 | ||
850 | /* Enumerators and enum types which are local to this class need not | |
851 | be laid out. Likewise for initialized constant fields. */ | |
852 | else if (TREE_CODE (field) != FIELD_DECL) | |
853 | return; | |
854 | ||
855 | /* Unions are laid out very differently than records, so split | |
856 | that code off to another function. */ | |
857 | else if (TREE_CODE (rli->t) != RECORD_TYPE) | |
858 | { | |
859 | place_union_field (rli, field); | |
860 | return; | |
861 | } | |
862 | ||
0ac11108 | 863 | else if (TREE_CODE (type) == ERROR_MARK) |
9dfb66b9 CD |
864 | { |
865 | /* Place this field at the current allocation position, so we | |
866 | maintain monotonicity. */ | |
867 | DECL_FIELD_OFFSET (field) = rli->offset; | |
868 | DECL_FIELD_BIT_OFFSET (field) = rli->bitpos; | |
869 | SET_DECL_OFFSET_ALIGN (field, rli->offset_align); | |
870 | return; | |
871 | } | |
872 | ||
0645ba8f MM |
873 | /* Work out the known alignment so far. Note that A & (-A) is the |
874 | value of the least-significant bit in A that is one. */ | |
875 | if (! integer_zerop (rli->bitpos)) | |
876 | known_align = (tree_low_cst (rli->bitpos, 1) | |
877 | & - tree_low_cst (rli->bitpos, 1)); | |
878 | else if (integer_zerop (rli->offset)) | |
cbbaf4ae | 879 | known_align = 0; |
0645ba8f MM |
880 | else if (host_integerp (rli->offset, 1)) |
881 | known_align = (BITS_PER_UNIT | |
882 | * (tree_low_cst (rli->offset, 1) | |
883 | & - tree_low_cst (rli->offset, 1))); | |
884 | else | |
885 | known_align = rli->offset_align; | |
46c5ad27 | 886 | |
0645ba8f | 887 | desired_align = update_alignment_for_field (rli, field, known_align); |
cbbaf4ae R |
888 | if (known_align == 0) |
889 | known_align = MAX (BIGGEST_ALIGNMENT, rli->record_align); | |
0645ba8f | 890 | |
9328904c MM |
891 | if (warn_packed && DECL_PACKED (field)) |
892 | { | |
78d55cc8 | 893 | if (known_align >= TYPE_ALIGN (type)) |
3c12fcc2 | 894 | { |
9328904c | 895 | if (TYPE_ALIGN (type) > desired_align) |
3c12fcc2 | 896 | { |
9328904c | 897 | if (STRICT_ALIGNMENT) |
dee15844 JM |
898 | warning (OPT_Wattributes, "packed attribute causes " |
899 | "inefficient alignment for %q+D", field); | |
9328904c | 900 | else |
dee15844 JM |
901 | warning (OPT_Wattributes, "packed attribute is " |
902 | "unnecessary for %q+D", field); | |
3c12fcc2 | 903 | } |
3c12fcc2 | 904 | } |
9328904c MM |
905 | else |
906 | rli->packed_maybe_necessary = 1; | |
907 | } | |
7306ed3f | 908 | |
9328904c | 909 | /* Does this field automatically have alignment it needs by virtue |
0ac11108 EC |
910 | of the fields that precede it and the record's own alignment? |
911 | We already align ms_struct fields, so don't re-align them. */ | |
912 | if (known_align < desired_align | |
913 | && !targetm.ms_bitfield_layout_p (rli->t)) | |
9328904c MM |
914 | { |
915 | /* No, we need to skip space before this field. | |
916 | Bump the cumulative size to multiple of field alignment. */ | |
7306ed3f | 917 | |
dee15844 | 918 | warning (OPT_Wpadded, "padding struct to align %q+D", field); |
3c12fcc2 | 919 | |
770ae6cc RK |
920 | /* If the alignment is still within offset_align, just align |
921 | the bit position. */ | |
922 | if (desired_align < rli->offset_align) | |
923 | rli->bitpos = round_up (rli->bitpos, desired_align); | |
9328904c MM |
924 | else |
925 | { | |
770ae6cc RK |
926 | /* First adjust OFFSET by the partial bits, then align. */ |
927 | rli->offset | |
928 | = size_binop (PLUS_EXPR, rli->offset, | |
455f19cb MM |
929 | fold_convert (sizetype, |
930 | size_binop (CEIL_DIV_EXPR, rli->bitpos, | |
931 | bitsize_unit_node))); | |
770ae6cc RK |
932 | rli->bitpos = bitsize_zero_node; |
933 | ||
934 | rli->offset = round_up (rli->offset, desired_align / BITS_PER_UNIT); | |
7306ed3f | 935 | } |
770ae6cc | 936 | |
b1254b72 RK |
937 | if (! TREE_CONSTANT (rli->offset)) |
938 | rli->offset_align = desired_align; | |
939 | ||
9328904c | 940 | } |
7306ed3f | 941 | |
770ae6cc RK |
942 | /* Handle compatibility with PCC. Note that if the record has any |
943 | variable-sized fields, we need not worry about compatibility. */ | |
7306ed3f | 944 | #ifdef PCC_BITFIELD_TYPE_MATTERS |
9328904c | 945 | if (PCC_BITFIELD_TYPE_MATTERS |
245f1bfa | 946 | && ! targetm.ms_bitfield_layout_p (rli->t) |
9328904c MM |
947 | && TREE_CODE (field) == FIELD_DECL |
948 | && type != error_mark_node | |
770ae6cc RK |
949 | && DECL_BIT_FIELD (field) |
950 | && ! DECL_PACKED (field) | |
9328904c | 951 | && maximum_field_alignment == 0 |
770ae6cc RK |
952 | && ! integer_zerop (DECL_SIZE (field)) |
953 | && host_integerp (DECL_SIZE (field), 1) | |
954 | && host_integerp (rli->offset, 1) | |
955 | && host_integerp (TYPE_SIZE (type), 1)) | |
9328904c MM |
956 | { |
957 | unsigned int type_align = TYPE_ALIGN (type); | |
770ae6cc RK |
958 | tree dsize = DECL_SIZE (field); |
959 | HOST_WIDE_INT field_size = tree_low_cst (dsize, 1); | |
960 | HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0); | |
961 | HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0); | |
9328904c | 962 | |
ad9335eb JJ |
963 | #ifdef ADJUST_FIELD_ALIGN |
964 | if (! TYPE_USER_ALIGN (type)) | |
965 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
966 | #endif | |
967 | ||
9328904c MM |
968 | /* A bit field may not span more units of alignment of its type |
969 | than its type itself. Advance to next boundary if necessary. */ | |
4977bab6 | 970 | if (excess_unit_span (offset, bit_offset, field_size, type_align, type)) |
770ae6cc | 971 | rli->bitpos = round_up (rli->bitpos, type_align); |
daf06049 | 972 | |
0645ba8f | 973 | TYPE_USER_ALIGN (rli->t) |= TYPE_USER_ALIGN (type); |
9328904c | 974 | } |
7306ed3f JW |
975 | #endif |
976 | ||
7306ed3f | 977 | #ifdef BITFIELD_NBYTES_LIMITED |
9328904c | 978 | if (BITFIELD_NBYTES_LIMITED |
245f1bfa | 979 | && ! targetm.ms_bitfield_layout_p (rli->t) |
9328904c MM |
980 | && TREE_CODE (field) == FIELD_DECL |
981 | && type != error_mark_node | |
982 | && DECL_BIT_FIELD_TYPE (field) | |
770ae6cc RK |
983 | && ! DECL_PACKED (field) |
984 | && ! integer_zerop (DECL_SIZE (field)) | |
985 | && host_integerp (DECL_SIZE (field), 1) | |
163d3408 | 986 | && host_integerp (rli->offset, 1) |
770ae6cc | 987 | && host_integerp (TYPE_SIZE (type), 1)) |
9328904c MM |
988 | { |
989 | unsigned int type_align = TYPE_ALIGN (type); | |
770ae6cc RK |
990 | tree dsize = DECL_SIZE (field); |
991 | HOST_WIDE_INT field_size = tree_low_cst (dsize, 1); | |
992 | HOST_WIDE_INT offset = tree_low_cst (rli->offset, 0); | |
993 | HOST_WIDE_INT bit_offset = tree_low_cst (rli->bitpos, 0); | |
e2301a83 | 994 | |
ad9335eb JJ |
995 | #ifdef ADJUST_FIELD_ALIGN |
996 | if (! TYPE_USER_ALIGN (type)) | |
997 | type_align = ADJUST_FIELD_ALIGN (field, type_align); | |
998 | #endif | |
999 | ||
9328904c MM |
1000 | if (maximum_field_alignment != 0) |
1001 | type_align = MIN (type_align, maximum_field_alignment); | |
1002 | /* ??? This test is opposite the test in the containing if | |
1003 | statement, so this code is unreachable currently. */ | |
1004 | else if (DECL_PACKED (field)) | |
1005 | type_align = MIN (type_align, BITS_PER_UNIT); | |
1006 | ||
1007 | /* A bit field may not span the unit of alignment of its type. | |
1008 | Advance to next boundary if necessary. */ | |
4977bab6 | 1009 | if (excess_unit_span (offset, bit_offset, field_size, type_align, type)) |
770ae6cc | 1010 | rli->bitpos = round_up (rli->bitpos, type_align); |
daf06049 | 1011 | |
0645ba8f | 1012 | TYPE_USER_ALIGN (rli->t) |= TYPE_USER_ALIGN (type); |
9328904c | 1013 | } |
7306ed3f JW |
1014 | #endif |
1015 | ||
e4850f36 DR |
1016 | /* See the docs for TARGET_MS_BITFIELD_LAYOUT_P for details. |
1017 | A subtlety: | |
1018 | When a bit field is inserted into a packed record, the whole | |
1019 | size of the underlying type is used by one or more same-size | |
4977bab6 | 1020 | adjacent bitfields. (That is, if its long:3, 32 bits is |
e4850f36 DR |
1021 | used in the record, and any additional adjacent long bitfields are |
1022 | packed into the same chunk of 32 bits. However, if the size | |
1023 | changes, a new field of that size is allocated.) In an unpacked | |
14b493d6 | 1024 | record, this is the same as using alignment, but not equivalent |
4977bab6 | 1025 | when packing. |
e4850f36 | 1026 | |
14b493d6 | 1027 | Note: for compatibility, we use the type size, not the type alignment |
e4850f36 DR |
1028 | to determine alignment, since that matches the documentation */ |
1029 | ||
0ac11108 | 1030 | if (targetm.ms_bitfield_layout_p (rli->t)) |
f913c102 | 1031 | { |
e4850f36 | 1032 | tree prev_saved = rli->prev_field; |
72aeff7c | 1033 | tree prev_type = prev_saved ? DECL_BIT_FIELD_TYPE (prev_saved) : NULL; |
f913c102 | 1034 | |
0ac11108 EC |
1035 | /* This is a bitfield if it exists. */ |
1036 | if (rli->prev_field) | |
e4850f36 DR |
1037 | { |
1038 | /* If both are bitfields, nonzero, and the same size, this is | |
1039 | the middle of a run. Zero declared size fields are special | |
1040 | and handled as "end of run". (Note: it's nonzero declared | |
1041 | size, but equal type sizes!) (Since we know that both | |
1042 | the current and previous fields are bitfields by the | |
1043 | time we check it, DECL_SIZE must be present for both.) */ | |
1044 | if (DECL_BIT_FIELD_TYPE (field) | |
1045 | && !integer_zerop (DECL_SIZE (field)) | |
1046 | && !integer_zerop (DECL_SIZE (rli->prev_field)) | |
0384674e RK |
1047 | && host_integerp (DECL_SIZE (rli->prev_field), 0) |
1048 | && host_integerp (TYPE_SIZE (type), 0) | |
72aeff7c | 1049 | && simple_cst_equal (TYPE_SIZE (type), TYPE_SIZE (prev_type))) |
e4850f36 DR |
1050 | { |
1051 | /* We're in the middle of a run of equal type size fields; make | |
1052 | sure we realign if we run out of bits. (Not decl size, | |
1053 | type size!) */ | |
0ac11108 | 1054 | HOST_WIDE_INT bitsize = tree_low_cst (DECL_SIZE (field), 1); |
e4850f36 DR |
1055 | |
1056 | if (rli->remaining_in_alignment < bitsize) | |
1057 | { | |
72aeff7c KK |
1058 | HOST_WIDE_INT typesize = tree_low_cst (TYPE_SIZE (type), 1); |
1059 | ||
0ac11108 | 1060 | /* out of bits; bump up to next 'word'. */ |
0ac11108 | 1061 | rli->bitpos |
72aeff7c KK |
1062 | = size_binop (PLUS_EXPR, rli->bitpos, |
1063 | bitsize_int (rli->remaining_in_alignment)); | |
0ac11108 | 1064 | rli->prev_field = field; |
72aeff7c KK |
1065 | if (typesize < bitsize) |
1066 | rli->remaining_in_alignment = 0; | |
1067 | else | |
1068 | rli->remaining_in_alignment = typesize - bitsize; | |
e4850f36 | 1069 | } |
72aeff7c KK |
1070 | else |
1071 | rli->remaining_in_alignment -= bitsize; | |
e4850f36 DR |
1072 | } |
1073 | else | |
1074 | { | |
4977bab6 ZW |
1075 | /* End of a run: if leaving a run of bitfields of the same type |
1076 | size, we have to "use up" the rest of the bits of the type | |
e4850f36 DR |
1077 | size. |
1078 | ||
1079 | Compute the new position as the sum of the size for the prior | |
1080 | type and where we first started working on that type. | |
1081 | Note: since the beginning of the field was aligned then | |
1082 | of course the end will be too. No round needed. */ | |
1083 | ||
f7eb0dcd | 1084 | if (!integer_zerop (DECL_SIZE (rli->prev_field))) |
e4850f36 | 1085 | { |
0ac11108 EC |
1086 | rli->bitpos |
1087 | = size_binop (PLUS_EXPR, rli->bitpos, | |
1088 | bitsize_int (rli->remaining_in_alignment)); | |
e4850f36 DR |
1089 | } |
1090 | else | |
0384674e RK |
1091 | /* We "use up" size zero fields; the code below should behave |
1092 | as if the prior field was not a bitfield. */ | |
1093 | prev_saved = NULL; | |
e4850f36 | 1094 | |
4977bab6 | 1095 | /* Cause a new bitfield to be captured, either this time (if |
991b6592 | 1096 | currently a bitfield) or next time we see one. */ |
e4850f36 | 1097 | if (!DECL_BIT_FIELD_TYPE(field) |
f7eb0dcd | 1098 | || integer_zerop (DECL_SIZE (field))) |
0384674e | 1099 | rli->prev_field = NULL; |
e4850f36 | 1100 | } |
0384674e | 1101 | |
e4850f36 DR |
1102 | normalize_rli (rli); |
1103 | } | |
1104 | ||
1105 | /* If we're starting a new run of same size type bitfields | |
1106 | (or a run of non-bitfields), set up the "first of the run" | |
4977bab6 | 1107 | fields. |
e4850f36 DR |
1108 | |
1109 | That is, if the current field is not a bitfield, or if there | |
1110 | was a prior bitfield the type sizes differ, or if there wasn't | |
1111 | a prior bitfield the size of the current field is nonzero. | |
1112 | ||
1113 | Note: we must be sure to test ONLY the type size if there was | |
1114 | a prior bitfield and ONLY for the current field being zero if | |
1115 | there wasn't. */ | |
1116 | ||
1117 | if (!DECL_BIT_FIELD_TYPE (field) | |
f7eb0dcd | 1118 | || (prev_saved != NULL |
72aeff7c | 1119 | ? !simple_cst_equal (TYPE_SIZE (type), TYPE_SIZE (prev_type)) |
0384674e | 1120 | : !integer_zerop (DECL_SIZE (field)) )) |
e4850f36 | 1121 | { |
0384674e RK |
1122 | /* Never smaller than a byte for compatibility. */ |
1123 | unsigned int type_align = BITS_PER_UNIT; | |
e4850f36 | 1124 | |
4977bab6 | 1125 | /* (When not a bitfield), we could be seeing a flex array (with |
e4850f36 | 1126 | no DECL_SIZE). Since we won't be using remaining_in_alignment |
4977bab6 | 1127 | until we see a bitfield (and come by here again) we just skip |
e4850f36 | 1128 | calculating it. */ |
0384674e RK |
1129 | if (DECL_SIZE (field) != NULL |
1130 | && host_integerp (TYPE_SIZE (TREE_TYPE (field)), 0) | |
1131 | && host_integerp (DECL_SIZE (field), 0)) | |
72aeff7c KK |
1132 | { |
1133 | HOST_WIDE_INT bitsize = tree_low_cst (DECL_SIZE (field), 1); | |
1134 | HOST_WIDE_INT typesize | |
1135 | = tree_low_cst (TYPE_SIZE (TREE_TYPE (field)), 1); | |
1136 | ||
1137 | if (typesize < bitsize) | |
1138 | rli->remaining_in_alignment = 0; | |
1139 | else | |
1140 | rli->remaining_in_alignment = typesize - bitsize; | |
1141 | } | |
e4850f36 | 1142 | |
991b6592 | 1143 | /* Now align (conventionally) for the new type. */ |
0ac11108 | 1144 | type_align = TYPE_ALIGN (TREE_TYPE (field)); |
f913c102 | 1145 | |
e4850f36 DR |
1146 | if (maximum_field_alignment != 0) |
1147 | type_align = MIN (type_align, maximum_field_alignment); | |
f913c102 | 1148 | |
e4850f36 | 1149 | rli->bitpos = round_up (rli->bitpos, type_align); |
0384674e | 1150 | |
e4850f36 | 1151 | /* If we really aligned, don't allow subsequent bitfields |
991b6592 | 1152 | to undo that. */ |
e4850f36 DR |
1153 | rli->prev_field = NULL; |
1154 | } | |
f913c102 AO |
1155 | } |
1156 | ||
770ae6cc RK |
1157 | /* Offset so far becomes the position of this field after normalizing. */ |
1158 | normalize_rli (rli); | |
1159 | DECL_FIELD_OFFSET (field) = rli->offset; | |
1160 | DECL_FIELD_BIT_OFFSET (field) = rli->bitpos; | |
2f5c7f45 | 1161 | SET_DECL_OFFSET_ALIGN (field, rli->offset_align); |
770ae6cc RK |
1162 | |
1163 | /* If this field ended up more aligned than we thought it would be (we | |
1164 | approximate this by seeing if its position changed), lay out the field | |
1165 | again; perhaps we can use an integral mode for it now. */ | |
4b6bf620 | 1166 | if (! integer_zerop (DECL_FIELD_BIT_OFFSET (field))) |
770ae6cc RK |
1167 | actual_align = (tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1) |
1168 | & - tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1)); | |
4b6bf620 | 1169 | else if (integer_zerop (DECL_FIELD_OFFSET (field))) |
cbbaf4ae | 1170 | actual_align = MAX (BIGGEST_ALIGNMENT, rli->record_align); |
770ae6cc RK |
1171 | else if (host_integerp (DECL_FIELD_OFFSET (field), 1)) |
1172 | actual_align = (BITS_PER_UNIT | |
1173 | * (tree_low_cst (DECL_FIELD_OFFSET (field), 1) | |
1174 | & - tree_low_cst (DECL_FIELD_OFFSET (field), 1))); | |
9328904c | 1175 | else |
770ae6cc | 1176 | actual_align = DECL_OFFSET_ALIGN (field); |
cbbaf4ae R |
1177 | /* ACTUAL_ALIGN is still the actual alignment *within the record* . |
1178 | store / extract bit field operations will check the alignment of the | |
1179 | record against the mode of bit fields. */ | |
770ae6cc RK |
1180 | |
1181 | if (known_align != actual_align) | |
1182 | layout_decl (field, actual_align); | |
1183 | ||
0ac11108 EC |
1184 | if (rli->prev_field == NULL && DECL_BIT_FIELD_TYPE (field)) |
1185 | rli->prev_field = field; | |
f913c102 | 1186 | |
770ae6cc RK |
1187 | /* Now add size of this field to the size of the record. If the size is |
1188 | not constant, treat the field as being a multiple of bytes and just | |
1189 | adjust the offset, resetting the bit position. Otherwise, apportion the | |
1190 | size amongst the bit position and offset. First handle the case of an | |
1191 | unspecified size, which can happen when we have an invalid nested struct | |
1192 | definition, such as struct j { struct j { int i; } }. The error message | |
1193 | is printed in finish_struct. */ | |
1194 | if (DECL_SIZE (field) == 0) | |
1195 | /* Do nothing. */; | |
292f30c5 | 1196 | else if (TREE_CODE (DECL_SIZE (field)) != INTEGER_CST |
455f14dd | 1197 | || TREE_OVERFLOW (DECL_SIZE (field))) |
9328904c | 1198 | { |
770ae6cc RK |
1199 | rli->offset |
1200 | = size_binop (PLUS_EXPR, rli->offset, | |
455f19cb MM |
1201 | fold_convert (sizetype, |
1202 | size_binop (CEIL_DIV_EXPR, rli->bitpos, | |
1203 | bitsize_unit_node))); | |
770ae6cc RK |
1204 | rli->offset |
1205 | = size_binop (PLUS_EXPR, rli->offset, DECL_SIZE_UNIT (field)); | |
1206 | rli->bitpos = bitsize_zero_node; | |
3923e410 | 1207 | rli->offset_align = MIN (rli->offset_align, desired_align); |
9328904c | 1208 | } |
0ac11108 EC |
1209 | else if (targetm.ms_bitfield_layout_p (rli->t)) |
1210 | { | |
1211 | rli->bitpos = size_binop (PLUS_EXPR, rli->bitpos, DECL_SIZE (field)); | |
1212 | ||
1213 | /* If we ended a bitfield before the full length of the type then | |
1214 | pad the struct out to the full length of the last type. */ | |
1215 | if ((TREE_CHAIN (field) == NULL | |
1216 | || TREE_CODE (TREE_CHAIN (field)) != FIELD_DECL) | |
1217 | && DECL_BIT_FIELD_TYPE (field) | |
1218 | && !integer_zerop (DECL_SIZE (field))) | |
1219 | rli->bitpos = size_binop (PLUS_EXPR, rli->bitpos, | |
1220 | bitsize_int (rli->remaining_in_alignment)); | |
1221 | ||
1222 | normalize_rli (rli); | |
1223 | } | |
9328904c MM |
1224 | else |
1225 | { | |
770ae6cc RK |
1226 | rli->bitpos = size_binop (PLUS_EXPR, rli->bitpos, DECL_SIZE (field)); |
1227 | normalize_rli (rli); | |
7306ed3f | 1228 | } |
9328904c | 1229 | } |
7306ed3f | 1230 | |
9328904c MM |
1231 | /* Assuming that all the fields have been laid out, this function uses |
1232 | RLI to compute the final TYPE_SIZE, TYPE_ALIGN, etc. for the type | |
14b493d6 | 1233 | indicated by RLI. */ |
7306ed3f | 1234 | |
9328904c | 1235 | static void |
46c5ad27 | 1236 | finalize_record_size (record_layout_info rli) |
9328904c | 1237 | { |
770ae6cc RK |
1238 | tree unpadded_size, unpadded_size_unit; |
1239 | ||
65e14bf5 RK |
1240 | /* Now we want just byte and bit offsets, so set the offset alignment |
1241 | to be a byte and then normalize. */ | |
1242 | rli->offset_align = BITS_PER_UNIT; | |
1243 | normalize_rli (rli); | |
7306ed3f JW |
1244 | |
1245 | /* Determine the desired alignment. */ | |
1246 | #ifdef ROUND_TYPE_ALIGN | |
9328904c | 1247 | TYPE_ALIGN (rli->t) = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t), |
b451555a | 1248 | rli->record_align); |
7306ed3f | 1249 | #else |
9328904c | 1250 | TYPE_ALIGN (rli->t) = MAX (TYPE_ALIGN (rli->t), rli->record_align); |
7306ed3f JW |
1251 | #endif |
1252 | ||
65e14bf5 RK |
1253 | /* Compute the size so far. Be sure to allow for extra bits in the |
1254 | size in bytes. We have guaranteed above that it will be no more | |
1255 | than a single byte. */ | |
1256 | unpadded_size = rli_size_so_far (rli); | |
1257 | unpadded_size_unit = rli_size_unit_so_far (rli); | |
1258 | if (! integer_zerop (rli->bitpos)) | |
1259 | unpadded_size_unit | |
1260 | = size_binop (PLUS_EXPR, unpadded_size_unit, size_one_node); | |
770ae6cc | 1261 | |
f9da5064 | 1262 | /* Round the size up to be a multiple of the required alignment. */ |
770ae6cc | 1263 | TYPE_SIZE (rli->t) = round_up (unpadded_size, TYPE_ALIGN (rli->t)); |
a4e9ffe5 RK |
1264 | TYPE_SIZE_UNIT (rli->t) |
1265 | = round_up (unpadded_size_unit, TYPE_ALIGN_UNIT (rli->t)); | |
729a2125 | 1266 | |
3176a0c2 | 1267 | if (TREE_CONSTANT (unpadded_size) |
770ae6cc | 1268 | && simple_cst_equal (unpadded_size, TYPE_SIZE (rli->t)) == 0) |
3176a0c2 | 1269 | warning (OPT_Wpadded, "padding struct size to alignment boundary"); |
786de7eb | 1270 | |
770ae6cc RK |
1271 | if (warn_packed && TREE_CODE (rli->t) == RECORD_TYPE |
1272 | && TYPE_PACKED (rli->t) && ! rli->packed_maybe_necessary | |
1273 | && TREE_CONSTANT (unpadded_size)) | |
3c12fcc2 GM |
1274 | { |
1275 | tree unpacked_size; | |
729a2125 | 1276 | |
3c12fcc2 | 1277 | #ifdef ROUND_TYPE_ALIGN |
9328904c MM |
1278 | rli->unpacked_align |
1279 | = ROUND_TYPE_ALIGN (rli->t, TYPE_ALIGN (rli->t), rli->unpacked_align); | |
3c12fcc2 | 1280 | #else |
9328904c | 1281 | rli->unpacked_align = MAX (TYPE_ALIGN (rli->t), rli->unpacked_align); |
3c12fcc2 | 1282 | #endif |
770ae6cc | 1283 | |
9328904c | 1284 | unpacked_size = round_up (TYPE_SIZE (rli->t), rli->unpacked_align); |
9328904c | 1285 | if (simple_cst_equal (unpacked_size, TYPE_SIZE (rli->t))) |
3c12fcc2 | 1286 | { |
770ae6cc RK |
1287 | TYPE_PACKED (rli->t) = 0; |
1288 | ||
9328904c | 1289 | if (TYPE_NAME (rli->t)) |
3c12fcc2 | 1290 | { |
63ad61ed | 1291 | const char *name; |
729a2125 | 1292 | |
9328904c MM |
1293 | if (TREE_CODE (TYPE_NAME (rli->t)) == IDENTIFIER_NODE) |
1294 | name = IDENTIFIER_POINTER (TYPE_NAME (rli->t)); | |
3c12fcc2 | 1295 | else |
9328904c | 1296 | name = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (rli->t))); |
770ae6cc | 1297 | |
3c12fcc2 | 1298 | if (STRICT_ALIGNMENT) |
3176a0c2 | 1299 | warning (OPT_Wpacked, "packed attribute causes inefficient " |
971801ff | 1300 | "alignment for %qs", name); |
3c12fcc2 | 1301 | else |
3176a0c2 | 1302 | warning (OPT_Wpacked, |
5c498b10 | 1303 | "packed attribute is unnecessary for %qs", name); |
3c12fcc2 GM |
1304 | } |
1305 | else | |
1306 | { | |
1307 | if (STRICT_ALIGNMENT) | |
3176a0c2 | 1308 | warning (OPT_Wpacked, |
5c498b10 | 1309 | "packed attribute causes inefficient alignment"); |
3c12fcc2 | 1310 | else |
3176a0c2 | 1311 | warning (OPT_Wpacked, "packed attribute is unnecessary"); |
3c12fcc2 GM |
1312 | } |
1313 | } | |
3c12fcc2 | 1314 | } |
9328904c MM |
1315 | } |
1316 | ||
1317 | /* Compute the TYPE_MODE for the TYPE (which is a RECORD_TYPE). */ | |
7306ed3f | 1318 | |
65e14bf5 | 1319 | void |
46c5ad27 | 1320 | compute_record_mode (tree type) |
9328904c | 1321 | { |
770ae6cc RK |
1322 | tree field; |
1323 | enum machine_mode mode = VOIDmode; | |
1324 | ||
9328904c MM |
1325 | /* Most RECORD_TYPEs have BLKmode, so we start off assuming that. |
1326 | However, if possible, we use a mode that fits in a register | |
1327 | instead, in order to allow for better optimization down the | |
1328 | line. */ | |
1329 | TYPE_MODE (type) = BLKmode; | |
9328904c | 1330 | |
770ae6cc RK |
1331 | if (! host_integerp (TYPE_SIZE (type), 1)) |
1332 | return; | |
9328904c | 1333 | |
770ae6cc RK |
1334 | /* A record which has any BLKmode members must itself be |
1335 | BLKmode; it can't go in a register. Unless the member is | |
1336 | BLKmode only because it isn't aligned. */ | |
1337 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) | |
1338 | { | |
770ae6cc RK |
1339 | if (TREE_CODE (field) != FIELD_DECL) |
1340 | continue; | |
9328904c | 1341 | |
770ae6cc RK |
1342 | if (TREE_CODE (TREE_TYPE (field)) == ERROR_MARK |
1343 | || (TYPE_MODE (TREE_TYPE (field)) == BLKmode | |
7a06d606 RK |
1344 | && ! TYPE_NO_FORCE_BLK (TREE_TYPE (field)) |
1345 | && !(TYPE_SIZE (TREE_TYPE (field)) != 0 | |
1346 | && integer_zerop (TYPE_SIZE (TREE_TYPE (field))))) | |
770ae6cc | 1347 | || ! host_integerp (bit_position (field), 1) |
6a9f6727 | 1348 | || DECL_SIZE (field) == 0 |
770ae6cc RK |
1349 | || ! host_integerp (DECL_SIZE (field), 1)) |
1350 | return; | |
1351 | ||
770ae6cc RK |
1352 | /* If this field is the whole struct, remember its mode so |
1353 | that, say, we can put a double in a class into a DF | |
a8ca7756 JW |
1354 | register instead of forcing it to live in the stack. */ |
1355 | if (simple_cst_equal (TYPE_SIZE (type), DECL_SIZE (field))) | |
770ae6cc | 1356 | mode = DECL_MODE (field); |
9328904c | 1357 | |
31a02448 | 1358 | #ifdef MEMBER_TYPE_FORCES_BLK |
770ae6cc RK |
1359 | /* With some targets, eg. c4x, it is sub-optimal |
1360 | to access an aligned BLKmode structure as a scalar. */ | |
0d7839da | 1361 | |
182e515e | 1362 | if (MEMBER_TYPE_FORCES_BLK (field, mode)) |
770ae6cc | 1363 | return; |
31a02448 | 1364 | #endif /* MEMBER_TYPE_FORCES_BLK */ |
770ae6cc | 1365 | } |
9328904c | 1366 | |
897f610b RS |
1367 | /* If we only have one real field; use its mode if that mode's size |
1368 | matches the type's size. This only applies to RECORD_TYPE. This | |
1369 | does not apply to unions. */ | |
1370 | if (TREE_CODE (type) == RECORD_TYPE && mode != VOIDmode | |
f439f9a5 R |
1371 | && host_integerp (TYPE_SIZE (type), 1) |
1372 | && GET_MODE_BITSIZE (mode) == TREE_INT_CST_LOW (TYPE_SIZE (type))) | |
770ae6cc | 1373 | TYPE_MODE (type) = mode; |
f439f9a5 R |
1374 | else |
1375 | TYPE_MODE (type) = mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1); | |
770ae6cc RK |
1376 | |
1377 | /* If structure's known alignment is less than what the scalar | |
1378 | mode would need, and it matters, then stick with BLKmode. */ | |
1379 | if (TYPE_MODE (type) != BLKmode | |
1380 | && STRICT_ALIGNMENT | |
1381 | && ! (TYPE_ALIGN (type) >= BIGGEST_ALIGNMENT | |
1382 | || TYPE_ALIGN (type) >= GET_MODE_ALIGNMENT (TYPE_MODE (type)))) | |
1383 | { | |
1384 | /* If this is the only reason this type is BLKmode, then | |
1385 | don't force containing types to be BLKmode. */ | |
1386 | TYPE_NO_FORCE_BLK (type) = 1; | |
1387 | TYPE_MODE (type) = BLKmode; | |
9328904c | 1388 | } |
7306ed3f | 1389 | } |
9328904c MM |
1390 | |
1391 | /* Compute TYPE_SIZE and TYPE_ALIGN for TYPE, once it has been laid | |
1392 | out. */ | |
1393 | ||
1394 | static void | |
46c5ad27 | 1395 | finalize_type_size (tree type) |
9328904c MM |
1396 | { |
1397 | /* Normally, use the alignment corresponding to the mode chosen. | |
1398 | However, where strict alignment is not required, avoid | |
1399 | over-aligning structures, since most compilers do not do this | |
490272b4 | 1400 | alignment. */ |
9328904c MM |
1401 | |
1402 | if (TYPE_MODE (type) != BLKmode && TYPE_MODE (type) != VOIDmode | |
490272b4 | 1403 | && (STRICT_ALIGNMENT |
9328904c MM |
1404 | || (TREE_CODE (type) != RECORD_TYPE && TREE_CODE (type) != UNION_TYPE |
1405 | && TREE_CODE (type) != QUAL_UNION_TYPE | |
1406 | && TREE_CODE (type) != ARRAY_TYPE))) | |
11cf4d18 | 1407 | { |
490272b4 RH |
1408 | unsigned mode_align = GET_MODE_ALIGNMENT (TYPE_MODE (type)); |
1409 | ||
1410 | /* Don't override a larger alignment requirement coming from a user | |
1411 | alignment of one of the fields. */ | |
1412 | if (mode_align >= TYPE_ALIGN (type)) | |
1413 | { | |
1414 | TYPE_ALIGN (type) = mode_align; | |
1415 | TYPE_USER_ALIGN (type) = 0; | |
1416 | } | |
11cf4d18 | 1417 | } |
9328904c MM |
1418 | |
1419 | /* Do machine-dependent extra alignment. */ | |
1420 | #ifdef ROUND_TYPE_ALIGN | |
1421 | TYPE_ALIGN (type) | |
1422 | = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (type), BITS_PER_UNIT); | |
1423 | #endif | |
1424 | ||
9328904c | 1425 | /* If we failed to find a simple way to calculate the unit size |
770ae6cc | 1426 | of the type, find it by division. */ |
9328904c MM |
1427 | if (TYPE_SIZE_UNIT (type) == 0 && TYPE_SIZE (type) != 0) |
1428 | /* TYPE_SIZE (type) is computed in bitsizetype. After the division, the | |
1429 | result will fit in sizetype. We will get more efficient code using | |
1430 | sizetype, so we force a conversion. */ | |
1431 | TYPE_SIZE_UNIT (type) | |
455f19cb MM |
1432 | = fold_convert (sizetype, |
1433 | size_binop (FLOOR_DIV_EXPR, TYPE_SIZE (type), | |
1434 | bitsize_unit_node)); | |
9328904c | 1435 | |
770ae6cc RK |
1436 | if (TYPE_SIZE (type) != 0) |
1437 | { | |
770ae6cc | 1438 | TYPE_SIZE (type) = round_up (TYPE_SIZE (type), TYPE_ALIGN (type)); |
a4e9ffe5 RK |
1439 | TYPE_SIZE_UNIT (type) = round_up (TYPE_SIZE_UNIT (type), |
1440 | TYPE_ALIGN_UNIT (type)); | |
770ae6cc RK |
1441 | } |
1442 | ||
1443 | /* Evaluate nonconstant sizes only once, either now or as soon as safe. */ | |
1444 | if (TYPE_SIZE (type) != 0 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) | |
1445 | TYPE_SIZE (type) = variable_size (TYPE_SIZE (type)); | |
9328904c MM |
1446 | if (TYPE_SIZE_UNIT (type) != 0 |
1447 | && TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST) | |
1448 | TYPE_SIZE_UNIT (type) = variable_size (TYPE_SIZE_UNIT (type)); | |
1449 | ||
1450 | /* Also layout any other variants of the type. */ | |
1451 | if (TYPE_NEXT_VARIANT (type) | |
1452 | || type != TYPE_MAIN_VARIANT (type)) | |
1453 | { | |
1454 | tree variant; | |
1455 | /* Record layout info of this variant. */ | |
1456 | tree size = TYPE_SIZE (type); | |
1457 | tree size_unit = TYPE_SIZE_UNIT (type); | |
1458 | unsigned int align = TYPE_ALIGN (type); | |
11cf4d18 | 1459 | unsigned int user_align = TYPE_USER_ALIGN (type); |
9328904c MM |
1460 | enum machine_mode mode = TYPE_MODE (type); |
1461 | ||
1462 | /* Copy it into all variants. */ | |
1463 | for (variant = TYPE_MAIN_VARIANT (type); | |
1464 | variant != 0; | |
1465 | variant = TYPE_NEXT_VARIANT (variant)) | |
1466 | { | |
1467 | TYPE_SIZE (variant) = size; | |
1468 | TYPE_SIZE_UNIT (variant) = size_unit; | |
1469 | TYPE_ALIGN (variant) = align; | |
11cf4d18 | 1470 | TYPE_USER_ALIGN (variant) = user_align; |
9328904c MM |
1471 | TYPE_MODE (variant) = mode; |
1472 | } | |
1473 | } | |
1474 | } | |
1475 | ||
1476 | /* Do all of the work required to layout the type indicated by RLI, | |
1477 | once the fields have been laid out. This function will call `free' | |
17bbb839 MM |
1478 | for RLI, unless FREE_P is false. Passing a value other than false |
1479 | for FREE_P is bad practice; this option only exists to support the | |
1480 | G++ 3.2 ABI. */ | |
9328904c MM |
1481 | |
1482 | void | |
46c5ad27 | 1483 | finish_record_layout (record_layout_info rli, int free_p) |
9328904c | 1484 | { |
1937f939 JM |
1485 | tree variant; |
1486 | ||
770ae6cc RK |
1487 | /* Compute the final size. */ |
1488 | finalize_record_size (rli); | |
1489 | ||
1490 | /* Compute the TYPE_MODE for the record. */ | |
1491 | compute_record_mode (rli->t); | |
cc9d4a85 | 1492 | |
8d8238b6 JM |
1493 | /* Perform any last tweaks to the TYPE_SIZE, etc. */ |
1494 | finalize_type_size (rli->t); | |
1495 | ||
1937f939 JM |
1496 | /* Propagate TYPE_PACKED to variants. With C++ templates, |
1497 | handle_packed_attribute is too early to do this. */ | |
1498 | for (variant = TYPE_NEXT_VARIANT (rli->t); variant; | |
1499 | variant = TYPE_NEXT_VARIANT (variant)) | |
1500 | TYPE_PACKED (variant) = TYPE_PACKED (rli->t); | |
1501 | ||
9328904c MM |
1502 | /* Lay out any static members. This is done now because their type |
1503 | may use the record's type. */ | |
1504 | while (rli->pending_statics) | |
1505 | { | |
1506 | layout_decl (TREE_VALUE (rli->pending_statics), 0); | |
1507 | rli->pending_statics = TREE_CHAIN (rli->pending_statics); | |
1508 | } | |
cc9d4a85 | 1509 | |
9328904c | 1510 | /* Clean up. */ |
17bbb839 MM |
1511 | if (free_p) |
1512 | free (rli); | |
9328904c | 1513 | } |
7306ed3f | 1514 | \f |
4977bab6 ZW |
1515 | |
1516 | /* Finish processing a builtin RECORD_TYPE type TYPE. It's name is | |
1517 | NAME, its fields are chained in reverse on FIELDS. | |
1518 | ||
1519 | If ALIGN_TYPE is non-null, it is given the same alignment as | |
1520 | ALIGN_TYPE. */ | |
1521 | ||
1522 | void | |
46c5ad27 AJ |
1523 | finish_builtin_struct (tree type, const char *name, tree fields, |
1524 | tree align_type) | |
4977bab6 ZW |
1525 | { |
1526 | tree tail, next; | |
1527 | ||
1528 | for (tail = NULL_TREE; fields; tail = fields, fields = next) | |
1529 | { | |
1530 | DECL_FIELD_CONTEXT (fields) = type; | |
1531 | next = TREE_CHAIN (fields); | |
1532 | TREE_CHAIN (fields) = tail; | |
1533 | } | |
1534 | TYPE_FIELDS (type) = tail; | |
1535 | ||
1536 | if (align_type) | |
1537 | { | |
1538 | TYPE_ALIGN (type) = TYPE_ALIGN (align_type); | |
1539 | TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (align_type); | |
1540 | } | |
1541 | ||
1542 | layout_type (type); | |
1543 | #if 0 /* not yet, should get fixed properly later */ | |
1544 | TYPE_NAME (type) = make_type_decl (get_identifier (name), type); | |
1545 | #else | |
1546 | TYPE_NAME (type) = build_decl (TYPE_DECL, get_identifier (name), type); | |
1547 | #endif | |
1548 | TYPE_STUB_DECL (type) = TYPE_NAME (type); | |
1549 | layout_decl (TYPE_NAME (type), 0); | |
1550 | } | |
1551 | ||
7306ed3f JW |
1552 | /* Calculate the mode, size, and alignment for TYPE. |
1553 | For an array type, calculate the element separation as well. | |
1554 | Record TYPE on the chain of permanent or temporary types | |
1555 | so that dbxout will find out about it. | |
1556 | ||
1557 | TYPE_SIZE of a type is nonzero if the type has been laid out already. | |
1558 | layout_type does nothing on such a type. | |
1559 | ||
1560 | If the type is incomplete, its TYPE_SIZE remains zero. */ | |
1561 | ||
1562 | void | |
46c5ad27 | 1563 | layout_type (tree type) |
7306ed3f | 1564 | { |
41374e13 | 1565 | gcc_assert (type); |
7306ed3f | 1566 | |
6de9cd9a DN |
1567 | if (type == error_mark_node) |
1568 | return; | |
1569 | ||
7306ed3f JW |
1570 | /* Do nothing if type has been laid out before. */ |
1571 | if (TYPE_SIZE (type)) | |
1572 | return; | |
1573 | ||
7306ed3f JW |
1574 | switch (TREE_CODE (type)) |
1575 | { | |
1576 | case LANG_TYPE: | |
1577 | /* This kind of type is the responsibility | |
9faa82d8 | 1578 | of the language-specific code. */ |
41374e13 | 1579 | gcc_unreachable (); |
7306ed3f | 1580 | |
2d76cb1a | 1581 | case BOOLEAN_TYPE: /* Used for Java, Pascal, and Chill. */ |
e9a25f70 | 1582 | if (TYPE_PRECISION (type) == 0) |
2d76cb1a | 1583 | TYPE_PRECISION (type) = 1; /* default to one byte/boolean. */ |
d4b60170 | 1584 | |
2d76cb1a | 1585 | /* ... fall through ... */ |
e9a25f70 | 1586 | |
7306ed3f JW |
1587 | case INTEGER_TYPE: |
1588 | case ENUMERAL_TYPE: | |
e2a77f99 RK |
1589 | if (TREE_CODE (TYPE_MIN_VALUE (type)) == INTEGER_CST |
1590 | && tree_int_cst_sgn (TYPE_MIN_VALUE (type)) >= 0) | |
8df83eae | 1591 | TYPE_UNSIGNED (type) = 1; |
7306ed3f | 1592 | |
5e9bec99 RK |
1593 | TYPE_MODE (type) = smallest_mode_for_size (TYPE_PRECISION (type), |
1594 | MODE_INT); | |
06ceef4e | 1595 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1596 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1597 | break; |
1598 | ||
1599 | case REAL_TYPE: | |
1600 | TYPE_MODE (type) = mode_for_size (TYPE_PRECISION (type), MODE_FLOAT, 0); | |
06ceef4e | 1601 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1602 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1603 | break; |
1604 | ||
1605 | case COMPLEX_TYPE: | |
8df83eae | 1606 | TYPE_UNSIGNED (type) = TYPE_UNSIGNED (TREE_TYPE (type)); |
7306ed3f JW |
1607 | TYPE_MODE (type) |
1608 | = mode_for_size (2 * TYPE_PRECISION (TREE_TYPE (type)), | |
8df83eae RK |
1609 | (TREE_CODE (TREE_TYPE (type)) == REAL_TYPE |
1610 | ? MODE_COMPLEX_FLOAT : MODE_COMPLEX_INT), | |
7306ed3f | 1611 | 0); |
06ceef4e | 1612 | TYPE_SIZE (type) = bitsize_int (GET_MODE_BITSIZE (TYPE_MODE (type))); |
ead17059 | 1613 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (TYPE_MODE (type))); |
7306ed3f JW |
1614 | break; |
1615 | ||
0b4565c9 | 1616 | case VECTOR_TYPE: |
26277d41 PB |
1617 | { |
1618 | int nunits = TYPE_VECTOR_SUBPARTS (type); | |
26277d41 PB |
1619 | tree innertype = TREE_TYPE (type); |
1620 | ||
41374e13 | 1621 | gcc_assert (!(nunits & (nunits - 1))); |
26277d41 PB |
1622 | |
1623 | /* Find an appropriate mode for the vector type. */ | |
1624 | if (TYPE_MODE (type) == VOIDmode) | |
1625 | { | |
1626 | enum machine_mode innermode = TYPE_MODE (innertype); | |
1627 | enum machine_mode mode; | |
1628 | ||
1629 | /* First, look for a supported vector type. */ | |
3d8bf70f | 1630 | if (SCALAR_FLOAT_MODE_P (innermode)) |
26277d41 PB |
1631 | mode = MIN_MODE_VECTOR_FLOAT; |
1632 | else | |
1633 | mode = MIN_MODE_VECTOR_INT; | |
1634 | ||
1635 | for (; mode != VOIDmode ; mode = GET_MODE_WIDER_MODE (mode)) | |
1636 | if (GET_MODE_NUNITS (mode) == nunits | |
1637 | && GET_MODE_INNER (mode) == innermode | |
f676971a | 1638 | && targetm.vector_mode_supported_p (mode)) |
26277d41 PB |
1639 | break; |
1640 | ||
1641 | /* For integers, try mapping it to a same-sized scalar mode. */ | |
1642 | if (mode == VOIDmode | |
1643 | && GET_MODE_CLASS (innermode) == MODE_INT) | |
1644 | mode = mode_for_size (nunits * GET_MODE_BITSIZE (innermode), | |
1645 | MODE_INT, 0); | |
1646 | ||
1647 | if (mode == VOIDmode || !have_regs_of_mode[mode]) | |
1648 | TYPE_MODE (type) = BLKmode; | |
1649 | else | |
1650 | TYPE_MODE (type) = mode; | |
1651 | } | |
1652 | ||
1653 | TYPE_UNSIGNED (type) = TYPE_UNSIGNED (TREE_TYPE (type)); | |
1654 | TYPE_SIZE_UNIT (type) = int_const_binop (MULT_EXPR, | |
1655 | TYPE_SIZE_UNIT (innertype), | |
000d8d44 | 1656 | size_int (nunits), 0); |
26277d41 | 1657 | TYPE_SIZE (type) = int_const_binop (MULT_EXPR, TYPE_SIZE (innertype), |
000d8d44 | 1658 | bitsize_int (nunits), 0); |
e4ca3dc3 | 1659 | |
34bc6352 | 1660 | /* Always naturally align vectors. This prevents ABI changes |
e4ca3dc3 RH |
1661 | depending on whether or not native vector modes are supported. */ |
1662 | TYPE_ALIGN (type) = tree_low_cst (TYPE_SIZE (type), 0); | |
26277d41 PB |
1663 | break; |
1664 | } | |
0b4565c9 | 1665 | |
7306ed3f | 1666 | case VOID_TYPE: |
770ae6cc | 1667 | /* This is an incomplete type and so doesn't have a size. */ |
7306ed3f | 1668 | TYPE_ALIGN (type) = 1; |
11cf4d18 | 1669 | TYPE_USER_ALIGN (type) = 0; |
7306ed3f JW |
1670 | TYPE_MODE (type) = VOIDmode; |
1671 | break; | |
1672 | ||
321cb743 | 1673 | case OFFSET_TYPE: |
06ceef4e | 1674 | TYPE_SIZE (type) = bitsize_int (POINTER_SIZE); |
ead17059 | 1675 | TYPE_SIZE_UNIT (type) = size_int (POINTER_SIZE / BITS_PER_UNIT); |
25caaba8 R |
1676 | /* A pointer might be MODE_PARTIAL_INT, |
1677 | but ptrdiff_t must be integral. */ | |
1678 | TYPE_MODE (type) = mode_for_size (POINTER_SIZE, MODE_INT, 0); | |
321cb743 MT |
1679 | break; |
1680 | ||
7306ed3f JW |
1681 | case FUNCTION_TYPE: |
1682 | case METHOD_TYPE: | |
019dd4ec RK |
1683 | /* It's hard to see what the mode and size of a function ought to |
1684 | be, but we do know the alignment is FUNCTION_BOUNDARY, so | |
1685 | make it consistent with that. */ | |
1686 | TYPE_MODE (type) = mode_for_size (FUNCTION_BOUNDARY, MODE_INT, 0); | |
1687 | TYPE_SIZE (type) = bitsize_int (FUNCTION_BOUNDARY); | |
1688 | TYPE_SIZE_UNIT (type) = size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT); | |
7306ed3f JW |
1689 | break; |
1690 | ||
1691 | case POINTER_TYPE: | |
1692 | case REFERENCE_TYPE: | |
b5d6a2ff | 1693 | { |
b5d6a2ff | 1694 | |
4977bab6 ZW |
1695 | enum machine_mode mode = ((TREE_CODE (type) == REFERENCE_TYPE |
1696 | && reference_types_internal) | |
1697 | ? Pmode : TYPE_MODE (type)); | |
1698 | ||
1699 | int nbits = GET_MODE_BITSIZE (mode); | |
1700 | ||
b5d6a2ff | 1701 | TYPE_SIZE (type) = bitsize_int (nbits); |
4977bab6 | 1702 | TYPE_SIZE_UNIT (type) = size_int (GET_MODE_SIZE (mode)); |
8df83eae | 1703 | TYPE_UNSIGNED (type) = 1; |
b5d6a2ff RK |
1704 | TYPE_PRECISION (type) = nbits; |
1705 | } | |
7306ed3f JW |
1706 | break; |
1707 | ||
1708 | case ARRAY_TYPE: | |
1709 | { | |
b3694847 SS |
1710 | tree index = TYPE_DOMAIN (type); |
1711 | tree element = TREE_TYPE (type); | |
7306ed3f JW |
1712 | |
1713 | build_pointer_type (element); | |
1714 | ||
1715 | /* We need to know both bounds in order to compute the size. */ | |
1716 | if (index && TYPE_MAX_VALUE (index) && TYPE_MIN_VALUE (index) | |
1717 | && TYPE_SIZE (element)) | |
1718 | { | |
ad50bc8d RH |
1719 | tree ub = TYPE_MAX_VALUE (index); |
1720 | tree lb = TYPE_MIN_VALUE (index); | |
e24ff973 | 1721 | tree length; |
74a4fbfc | 1722 | tree element_size; |
e24ff973 | 1723 | |
a2d53b28 RH |
1724 | /* The initial subtraction should happen in the original type so |
1725 | that (possible) negative values are handled appropriately. */ | |
e24ff973 | 1726 | length = size_binop (PLUS_EXPR, size_one_node, |
455f19cb | 1727 | fold_convert (sizetype, |
4845b383 KH |
1728 | fold_build2 (MINUS_EXPR, |
1729 | TREE_TYPE (lb), | |
1730 | ub, lb))); | |
7306ed3f | 1731 | |
74a4fbfc DB |
1732 | /* Special handling for arrays of bits (for Chill). */ |
1733 | element_size = TYPE_SIZE (element); | |
382110c0 RK |
1734 | if (TYPE_PACKED (type) && INTEGRAL_TYPE_P (element) |
1735 | && (integer_zerop (TYPE_MAX_VALUE (element)) | |
1736 | || integer_onep (TYPE_MAX_VALUE (element))) | |
1737 | && host_integerp (TYPE_MIN_VALUE (element), 1)) | |
74a4fbfc | 1738 | { |
d4b60170 | 1739 | HOST_WIDE_INT maxvalue |
382110c0 | 1740 | = tree_low_cst (TYPE_MAX_VALUE (element), 1); |
d4b60170 | 1741 | HOST_WIDE_INT minvalue |
382110c0 | 1742 | = tree_low_cst (TYPE_MIN_VALUE (element), 1); |
d4b60170 | 1743 | |
74a4fbfc DB |
1744 | if (maxvalue - minvalue == 1 |
1745 | && (maxvalue == 1 || maxvalue == 0)) | |
1746 | element_size = integer_one_node; | |
1747 | } | |
1748 | ||
0d3c8800 RK |
1749 | /* If neither bound is a constant and sizetype is signed, make |
1750 | sure the size is never negative. We should really do this | |
1751 | if *either* bound is non-constant, but this is the best | |
1752 | compromise between C and Ada. */ | |
8df83eae | 1753 | if (!TYPE_UNSIGNED (sizetype) |
0d3c8800 RK |
1754 | && TREE_CODE (TYPE_MIN_VALUE (index)) != INTEGER_CST |
1755 | && TREE_CODE (TYPE_MAX_VALUE (index)) != INTEGER_CST) | |
1756 | length = size_binop (MAX_EXPR, length, size_zero_node); | |
1757 | ||
fed3cef0 | 1758 | TYPE_SIZE (type) = size_binop (MULT_EXPR, element_size, |
0ac11108 | 1759 | fold_convert (bitsizetype, |
455f19cb | 1760 | length)); |
ead17059 RH |
1761 | |
1762 | /* If we know the size of the element, calculate the total | |
1763 | size directly, rather than do some division thing below. | |
1764 | This optimization helps Fortran assumed-size arrays | |
1765 | (where the size of the array is determined at runtime) | |
7771032e DB |
1766 | substantially. |
1767 | Note that we can't do this in the case where the size of | |
1768 | the elements is one bit since TYPE_SIZE_UNIT cannot be | |
1769 | set correctly in that case. */ | |
fed3cef0 | 1770 | if (TYPE_SIZE_UNIT (element) != 0 && ! integer_onep (element_size)) |
d4b60170 RK |
1771 | TYPE_SIZE_UNIT (type) |
1772 | = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (element), length); | |
7306ed3f JW |
1773 | } |
1774 | ||
1775 | /* Now round the alignment and size, | |
1776 | using machine-dependent criteria if any. */ | |
1777 | ||
1778 | #ifdef ROUND_TYPE_ALIGN | |
1779 | TYPE_ALIGN (type) | |
1780 | = ROUND_TYPE_ALIGN (type, TYPE_ALIGN (element), BITS_PER_UNIT); | |
1781 | #else | |
1782 | TYPE_ALIGN (type) = MAX (TYPE_ALIGN (element), BITS_PER_UNIT); | |
1783 | #endif | |
06d40de8 DG |
1784 | if (!TYPE_SIZE (element)) |
1785 | /* We don't know the size of the underlying element type, so | |
1786 | our alignment calculations will be wrong, forcing us to | |
1787 | fall back on structural equality. */ | |
1788 | SET_TYPE_STRUCTURAL_EQUALITY (type); | |
c163d21d | 1789 | TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (element); |
7306ed3f JW |
1790 | TYPE_MODE (type) = BLKmode; |
1791 | if (TYPE_SIZE (type) != 0 | |
31a02448 | 1792 | #ifdef MEMBER_TYPE_FORCES_BLK |
182e515e | 1793 | && ! MEMBER_TYPE_FORCES_BLK (type, VOIDmode) |
31a02448 | 1794 | #endif |
7306ed3f JW |
1795 | /* BLKmode elements force BLKmode aggregate; |
1796 | else extract/store fields may lose. */ | |
1797 | && (TYPE_MODE (TREE_TYPE (type)) != BLKmode | |
1798 | || TYPE_NO_FORCE_BLK (TREE_TYPE (type)))) | |
1799 | { | |
a1471322 RK |
1800 | /* One-element arrays get the component type's mode. */ |
1801 | if (simple_cst_equal (TYPE_SIZE (type), | |
1802 | TYPE_SIZE (TREE_TYPE (type)))) | |
1803 | TYPE_MODE (type) = TYPE_MODE (TREE_TYPE (type)); | |
1804 | else | |
1805 | TYPE_MODE (type) | |
1806 | = mode_for_size_tree (TYPE_SIZE (type), MODE_INT, 1); | |
7306ed3f | 1807 | |
72c602fc RK |
1808 | if (TYPE_MODE (type) != BLKmode |
1809 | && STRICT_ALIGNMENT && TYPE_ALIGN (type) < BIGGEST_ALIGNMENT | |
b9d49351 | 1810 | && TYPE_ALIGN (type) < GET_MODE_ALIGNMENT (TYPE_MODE (type))) |
7306ed3f JW |
1811 | { |
1812 | TYPE_NO_FORCE_BLK (type) = 1; | |
1813 | TYPE_MODE (type) = BLKmode; | |
1814 | } | |
7306ed3f | 1815 | } |
b606b65c OH |
1816 | /* When the element size is constant, check that it is at least as |
1817 | large as the element alignment. */ | |
002a9071 SE |
1818 | if (TYPE_SIZE_UNIT (element) |
1819 | && TREE_CODE (TYPE_SIZE_UNIT (element)) == INTEGER_CST | |
b606b65c OH |
1820 | /* If TYPE_SIZE_UNIT overflowed, then it is certainly larger than |
1821 | TYPE_ALIGN_UNIT. */ | |
455f14dd | 1822 | && !TREE_OVERFLOW (TYPE_SIZE_UNIT (element)) |
002a9071 SE |
1823 | && !integer_zerop (TYPE_SIZE_UNIT (element)) |
1824 | && compare_tree_int (TYPE_SIZE_UNIT (element), | |
1825 | TYPE_ALIGN_UNIT (element)) < 0) | |
1826 | error ("alignment of array elements is greater than element size"); | |
7306ed3f JW |
1827 | break; |
1828 | } | |
1829 | ||
1830 | case RECORD_TYPE: | |
cc9d4a85 MM |
1831 | case UNION_TYPE: |
1832 | case QUAL_UNION_TYPE: | |
9328904c MM |
1833 | { |
1834 | tree field; | |
1835 | record_layout_info rli; | |
1836 | ||
1837 | /* Initialize the layout information. */ | |
770ae6cc RK |
1838 | rli = start_record_layout (type); |
1839 | ||
cc9d4a85 MM |
1840 | /* If this is a QUAL_UNION_TYPE, we want to process the fields |
1841 | in the reverse order in building the COND_EXPR that denotes | |
1842 | its size. We reverse them again later. */ | |
1843 | if (TREE_CODE (type) == QUAL_UNION_TYPE) | |
1844 | TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type)); | |
770ae6cc RK |
1845 | |
1846 | /* Place all the fields. */ | |
9328904c | 1847 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) |
770ae6cc RK |
1848 | place_field (rli, field); |
1849 | ||
cc9d4a85 MM |
1850 | if (TREE_CODE (type) == QUAL_UNION_TYPE) |
1851 | TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type)); | |
770ae6cc | 1852 | |
e0cea8d9 RK |
1853 | if (lang_adjust_rli) |
1854 | (*lang_adjust_rli) (rli); | |
1855 | ||
9328904c | 1856 | /* Finish laying out the record. */ |
17bbb839 | 1857 | finish_record_layout (rli, /*free_p=*/true); |
9328904c | 1858 | } |
7306ed3f JW |
1859 | break; |
1860 | ||
7306ed3f | 1861 | default: |
41374e13 | 1862 | gcc_unreachable (); |
729a2125 | 1863 | } |
7306ed3f | 1864 | |
9328904c | 1865 | /* Compute the final TYPE_SIZE, TYPE_ALIGN, etc. for TYPE. For |
cc9d4a85 MM |
1866 | records and unions, finish_record_layout already called this |
1867 | function. */ | |
786de7eb | 1868 | if (TREE_CODE (type) != RECORD_TYPE |
cc9d4a85 MM |
1869 | && TREE_CODE (type) != UNION_TYPE |
1870 | && TREE_CODE (type) != QUAL_UNION_TYPE) | |
9328904c | 1871 | finalize_type_size (type); |
7306ed3f | 1872 | |
dc5041ab JJ |
1873 | /* If an alias set has been set for this aggregate when it was incomplete, |
1874 | force it into alias set 0. | |
1875 | This is too conservative, but we cannot call record_component_aliases | |
1876 | here because some frontends still change the aggregates after | |
1877 | layout_type. */ | |
1878 | if (AGGREGATE_TYPE_P (type) && TYPE_ALIAS_SET_KNOWN_P (type)) | |
1879 | TYPE_ALIAS_SET (type) = 0; | |
7306ed3f JW |
1880 | } |
1881 | \f | |
1882 | /* Create and return a type for signed integers of PRECISION bits. */ | |
1883 | ||
1884 | tree | |
46c5ad27 | 1885 | make_signed_type (int precision) |
7306ed3f | 1886 | { |
b3694847 | 1887 | tree type = make_node (INTEGER_TYPE); |
7306ed3f JW |
1888 | |
1889 | TYPE_PRECISION (type) = precision; | |
1890 | ||
fed3cef0 | 1891 | fixup_signed_type (type); |
7306ed3f JW |
1892 | return type; |
1893 | } | |
1894 | ||
1895 | /* Create and return a type for unsigned integers of PRECISION bits. */ | |
1896 | ||
1897 | tree | |
46c5ad27 | 1898 | make_unsigned_type (int precision) |
7306ed3f | 1899 | { |
b3694847 | 1900 | tree type = make_node (INTEGER_TYPE); |
7306ed3f JW |
1901 | |
1902 | TYPE_PRECISION (type) = precision; | |
1903 | ||
7306ed3f JW |
1904 | fixup_unsigned_type (type); |
1905 | return type; | |
1906 | } | |
fed3cef0 RK |
1907 | \f |
1908 | /* Initialize sizetype and bitsizetype to a reasonable and temporary | |
1909 | value to enable integer types to be created. */ | |
1910 | ||
1911 | void | |
8c1d6d62 | 1912 | initialize_sizetypes (bool signed_p) |
fed3cef0 RK |
1913 | { |
1914 | tree t = make_node (INTEGER_TYPE); | |
a6a12bb9 | 1915 | int precision = GET_MODE_BITSIZE (SImode); |
fed3cef0 | 1916 | |
fed3cef0 RK |
1917 | TYPE_MODE (t) = SImode; |
1918 | TYPE_ALIGN (t) = GET_MODE_ALIGNMENT (SImode); | |
11cf4d18 | 1919 | TYPE_USER_ALIGN (t) = 0; |
3224bead | 1920 | TYPE_IS_SIZETYPE (t) = 1; |
8c1d6d62 | 1921 | TYPE_UNSIGNED (t) = !signed_p; |
a6a12bb9 | 1922 | TYPE_SIZE (t) = build_int_cst (t, precision); |
7d60be94 | 1923 | TYPE_SIZE_UNIT (t) = build_int_cst (t, GET_MODE_SIZE (SImode)); |
a6a12bb9 | 1924 | TYPE_PRECISION (t) = precision; |
fed3cef0 | 1925 | |
a6a12bb9 RS |
1926 | /* Set TYPE_MIN_VALUE and TYPE_MAX_VALUE. */ |
1927 | set_min_and_max_values_for_integral_type (t, precision, !signed_p); | |
fed3cef0 | 1928 | |
fed3cef0 | 1929 | sizetype = t; |
8c1d6d62 | 1930 | bitsizetype = build_distinct_type_copy (t); |
fed3cef0 | 1931 | } |
7306ed3f | 1932 | |
8c1d6d62 NS |
1933 | /* Make sizetype a version of TYPE, and initialize *sizetype |
1934 | accordingly. We do this by overwriting the stub sizetype and | |
1935 | bitsizetype nodes created by initialize_sizetypes. This makes sure | |
1936 | that (a) anything stubby about them no longer exists, (b) any | |
1937 | INTEGER_CSTs created with such a type, remain valid. */ | |
f8dac6eb R |
1938 | |
1939 | void | |
46c5ad27 | 1940 | set_sizetype (tree type) |
f8dac6eb | 1941 | { |
d4b60170 | 1942 | int oprecision = TYPE_PRECISION (type); |
f8dac6eb | 1943 | /* The *bitsizetype types use a precision that avoids overflows when |
d4b60170 RK |
1944 | calculating signed sizes / offsets in bits. However, when |
1945 | cross-compiling from a 32 bit to a 64 bit host, we are limited to 64 bit | |
1946 | precision. */ | |
30f421e5 JDA |
1947 | int precision = MIN (MIN (oprecision + BITS_PER_UNIT_LOG + 1, |
1948 | MAX_FIXED_MODE_SIZE), | |
d4b60170 | 1949 | 2 * HOST_BITS_PER_WIDE_INT); |
ad41cc2a | 1950 | tree t; |
fed3cef0 | 1951 | |
41374e13 | 1952 | gcc_assert (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (sizetype)); |
81b3411c | 1953 | |
8c1d6d62 NS |
1954 | t = build_distinct_type_copy (type); |
1955 | /* We do want to use sizetype's cache, as we will be replacing that | |
1956 | type. */ | |
1957 | TYPE_CACHED_VALUES (t) = TYPE_CACHED_VALUES (sizetype); | |
1958 | TYPE_CACHED_VALUES_P (t) = TYPE_CACHED_VALUES_P (sizetype); | |
1959 | TREE_TYPE (TYPE_CACHED_VALUES (t)) = type; | |
1960 | TYPE_UID (t) = TYPE_UID (sizetype); | |
1961 | TYPE_IS_SIZETYPE (t) = 1; | |
0ac11108 | 1962 | |
8c1d6d62 NS |
1963 | /* Replace our original stub sizetype. */ |
1964 | memcpy (sizetype, t, tree_size (sizetype)); | |
1965 | TYPE_MAIN_VARIANT (sizetype) = sizetype; | |
0ac11108 | 1966 | |
8c1d6d62 NS |
1967 | t = make_node (INTEGER_TYPE); |
1968 | TYPE_NAME (t) = get_identifier ("bit_size_type"); | |
1969 | /* We do want to use bitsizetype's cache, as we will be replacing that | |
1970 | type. */ | |
1971 | TYPE_CACHED_VALUES (t) = TYPE_CACHED_VALUES (bitsizetype); | |
1972 | TYPE_CACHED_VALUES_P (t) = TYPE_CACHED_VALUES_P (bitsizetype); | |
1973 | TYPE_PRECISION (t) = precision; | |
1974 | TYPE_UID (t) = TYPE_UID (bitsizetype); | |
1975 | TYPE_IS_SIZETYPE (t) = 1; | |
4ecd8dc7 | 1976 | |
8c1d6d62 NS |
1977 | /* Replace our original stub bitsizetype. */ |
1978 | memcpy (bitsizetype, t, tree_size (bitsizetype)); | |
4ecd8dc7 | 1979 | TYPE_MAIN_VARIANT (bitsizetype) = bitsizetype; |
0ac11108 | 1980 | |
8df83eae | 1981 | if (TYPE_UNSIGNED (type)) |
896cced4 | 1982 | { |
8c1d6d62 NS |
1983 | fixup_unsigned_type (bitsizetype); |
1984 | ssizetype = build_distinct_type_copy (make_signed_type (oprecision)); | |
1985 | TYPE_IS_SIZETYPE (ssizetype) = 1; | |
1986 | sbitsizetype = build_distinct_type_copy (make_signed_type (precision)); | |
1987 | TYPE_IS_SIZETYPE (sbitsizetype) = 1; | |
896cced4 RH |
1988 | } |
1989 | else | |
1990 | { | |
8c1d6d62 | 1991 | fixup_signed_type (bitsizetype); |
896cced4 RH |
1992 | ssizetype = sizetype; |
1993 | sbitsizetype = bitsizetype; | |
896cced4 | 1994 | } |
7f18f917 JL |
1995 | |
1996 | /* If SIZETYPE is unsigned, we need to fix TYPE_MAX_VALUE so that | |
1997 | it is sign extended in a way consistent with force_fit_type. */ | |
1998 | if (TYPE_UNSIGNED (type)) | |
1999 | { | |
2000 | tree orig_max, new_max; | |
2001 | ||
2002 | orig_max = TYPE_MAX_VALUE (sizetype); | |
2003 | ||
2ac7cbb5 RG |
2004 | /* Build a new node with the same values, but a different type. |
2005 | Sign extend it to ensure consistency. */ | |
2006 | new_max = build_int_cst_wide_type (sizetype, | |
2007 | TREE_INT_CST_LOW (orig_max), | |
2008 | TREE_INT_CST_HIGH (orig_max)); | |
7f18f917 JL |
2009 | TYPE_MAX_VALUE (sizetype) = new_max; |
2010 | } | |
fed3cef0 RK |
2011 | } |
2012 | \f | |
71d59383 RS |
2013 | /* TYPE is an integral type, i.e., an INTEGRAL_TYPE, ENUMERAL_TYPE |
2014 | or BOOLEAN_TYPE. Set TYPE_MIN_VALUE and TYPE_MAX_VALUE | |
7b6d72fc MM |
2015 | for TYPE, based on the PRECISION and whether or not the TYPE |
2016 | IS_UNSIGNED. PRECISION need not correspond to a width supported | |
2017 | natively by the hardware; for example, on a machine with 8-bit, | |
2018 | 16-bit, and 32-bit register modes, PRECISION might be 7, 23, or | |
2019 | 61. */ | |
2020 | ||
2021 | void | |
2022 | set_min_and_max_values_for_integral_type (tree type, | |
2023 | int precision, | |
2024 | bool is_unsigned) | |
2025 | { | |
2026 | tree min_value; | |
2027 | tree max_value; | |
2028 | ||
2029 | if (is_unsigned) | |
2030 | { | |
7d60be94 | 2031 | min_value = build_int_cst (type, 0); |
f676971a | 2032 | max_value |
7d60be94 NS |
2033 | = build_int_cst_wide (type, precision - HOST_BITS_PER_WIDE_INT >= 0 |
2034 | ? -1 | |
2035 | : ((HOST_WIDE_INT) 1 << precision) - 1, | |
2036 | precision - HOST_BITS_PER_WIDE_INT > 0 | |
2037 | ? ((unsigned HOST_WIDE_INT) ~0 | |
2038 | >> (HOST_BITS_PER_WIDE_INT | |
2039 | - (precision - HOST_BITS_PER_WIDE_INT))) | |
2040 | : 0); | |
7b6d72fc MM |
2041 | } |
2042 | else | |
2043 | { | |
f676971a | 2044 | min_value |
7d60be94 NS |
2045 | = build_int_cst_wide (type, |
2046 | (precision - HOST_BITS_PER_WIDE_INT > 0 | |
2047 | ? 0 | |
2048 | : (HOST_WIDE_INT) (-1) << (precision - 1)), | |
2049 | (((HOST_WIDE_INT) (-1) | |
2050 | << (precision - HOST_BITS_PER_WIDE_INT - 1 > 0 | |
2051 | ? precision - HOST_BITS_PER_WIDE_INT - 1 | |
2052 | : 0)))); | |
7b6d72fc | 2053 | max_value |
7d60be94 NS |
2054 | = build_int_cst_wide (type, |
2055 | (precision - HOST_BITS_PER_WIDE_INT > 0 | |
2056 | ? -1 | |
2057 | : ((HOST_WIDE_INT) 1 << (precision - 1)) - 1), | |
2058 | (precision - HOST_BITS_PER_WIDE_INT - 1 > 0 | |
2059 | ? (((HOST_WIDE_INT) 1 | |
2060 | << (precision - HOST_BITS_PER_WIDE_INT - 1))) - 1 | |
2061 | : 0)); | |
7b6d72fc MM |
2062 | } |
2063 | ||
7b6d72fc MM |
2064 | TYPE_MIN_VALUE (type) = min_value; |
2065 | TYPE_MAX_VALUE (type) = max_value; | |
2066 | } | |
2067 | ||
4cc89e53 | 2068 | /* Set the extreme values of TYPE based on its precision in bits, |
13756074 | 2069 | then lay it out. Used when make_signed_type won't do |
4cc89e53 RS |
2070 | because the tree code is not INTEGER_TYPE. |
2071 | E.g. for Pascal, when the -fsigned-char option is given. */ | |
2072 | ||
2073 | void | |
46c5ad27 | 2074 | fixup_signed_type (tree type) |
4cc89e53 | 2075 | { |
b3694847 | 2076 | int precision = TYPE_PRECISION (type); |
4cc89e53 | 2077 | |
9cd56be1 JH |
2078 | /* We can not represent properly constants greater then |
2079 | 2 * HOST_BITS_PER_WIDE_INT, still we need the types | |
2080 | as they are used by i386 vector extensions and friends. */ | |
2081 | if (precision > HOST_BITS_PER_WIDE_INT * 2) | |
2082 | precision = HOST_BITS_PER_WIDE_INT * 2; | |
2083 | ||
f676971a | 2084 | set_min_and_max_values_for_integral_type (type, precision, |
7b6d72fc | 2085 | /*is_unsigned=*/false); |
4cc89e53 RS |
2086 | |
2087 | /* Lay out the type: set its alignment, size, etc. */ | |
4cc89e53 RS |
2088 | layout_type (type); |
2089 | } | |
2090 | ||
7306ed3f | 2091 | /* Set the extreme values of TYPE based on its precision in bits, |
13756074 | 2092 | then lay it out. This is used both in `make_unsigned_type' |
7306ed3f JW |
2093 | and for enumeral types. */ |
2094 | ||
2095 | void | |
46c5ad27 | 2096 | fixup_unsigned_type (tree type) |
7306ed3f | 2097 | { |
b3694847 | 2098 | int precision = TYPE_PRECISION (type); |
7306ed3f | 2099 | |
9cd56be1 JH |
2100 | /* We can not represent properly constants greater then |
2101 | 2 * HOST_BITS_PER_WIDE_INT, still we need the types | |
2102 | as they are used by i386 vector extensions and friends. */ | |
2103 | if (precision > HOST_BITS_PER_WIDE_INT * 2) | |
2104 | precision = HOST_BITS_PER_WIDE_INT * 2; | |
2105 | ||
89b0433e | 2106 | TYPE_UNSIGNED (type) = 1; |
f676971a EC |
2107 | |
2108 | set_min_and_max_values_for_integral_type (type, precision, | |
7b6d72fc | 2109 | /*is_unsigned=*/true); |
7306ed3f JW |
2110 | |
2111 | /* Lay out the type: set its alignment, size, etc. */ | |
7306ed3f JW |
2112 | layout_type (type); |
2113 | } | |
2114 | \f | |
2115 | /* Find the best machine mode to use when referencing a bit field of length | |
2116 | BITSIZE bits starting at BITPOS. | |
2117 | ||
2118 | The underlying object is known to be aligned to a boundary of ALIGN bits. | |
2119 | If LARGEST_MODE is not VOIDmode, it means that we should not use a mode | |
2120 | larger than LARGEST_MODE (usually SImode). | |
2121 | ||
c2a64439 | 2122 | If no mode meets all these conditions, we return VOIDmode. |
0ac11108 | 2123 | |
c2a64439 PB |
2124 | If VOLATILEP is false and SLOW_BYTE_ACCESS is false, we return the |
2125 | smallest mode meeting these conditions. | |
2126 | ||
2127 | If VOLATILEP is false and SLOW_BYTE_ACCESS is true, we return the | |
2128 | largest mode (but a mode no wider than UNITS_PER_WORD) that meets | |
2129 | all the conditions. | |
0ac11108 | 2130 | |
c2a64439 PB |
2131 | If VOLATILEP is true the narrow_volatile_bitfields target hook is used to |
2132 | decide which of the above modes should be used. */ | |
7306ed3f JW |
2133 | |
2134 | enum machine_mode | |
46c5ad27 AJ |
2135 | get_best_mode (int bitsize, int bitpos, unsigned int align, |
2136 | enum machine_mode largest_mode, int volatilep) | |
7306ed3f JW |
2137 | { |
2138 | enum machine_mode mode; | |
770ae6cc | 2139 | unsigned int unit = 0; |
7306ed3f JW |
2140 | |
2141 | /* Find the narrowest integer mode that contains the bit field. */ | |
2142 | for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode; | |
2143 | mode = GET_MODE_WIDER_MODE (mode)) | |
2144 | { | |
2145 | unit = GET_MODE_BITSIZE (mode); | |
956d6950 | 2146 | if ((bitpos % unit) + bitsize <= unit) |
7306ed3f JW |
2147 | break; |
2148 | } | |
2149 | ||
0c61f541 | 2150 | if (mode == VOIDmode |
7306ed3f | 2151 | /* It is tempting to omit the following line |
4e4b555d | 2152 | if STRICT_ALIGNMENT is true. |
7306ed3f JW |
2153 | But that is incorrect, since if the bitfield uses part of 3 bytes |
2154 | and we use a 4-byte mode, we could get a spurious segv | |
2155 | if the extra 4th byte is past the end of memory. | |
2156 | (Though at least one Unix compiler ignores this problem: | |
2157 | that on the Sequent 386 machine. */ | |
770ae6cc | 2158 | || MIN (unit, BIGGEST_ALIGNMENT) > align |
7306ed3f JW |
2159 | || (largest_mode != VOIDmode && unit > GET_MODE_BITSIZE (largest_mode))) |
2160 | return VOIDmode; | |
2161 | ||
c2a64439 | 2162 | if ((SLOW_BYTE_ACCESS && ! volatilep) |
62e5bf5d | 2163 | || (volatilep && !targetm.narrow_volatile_bitfield ())) |
77fa0940 RK |
2164 | { |
2165 | enum machine_mode wide_mode = VOIDmode, tmode; | |
2166 | ||
2167 | for (tmode = GET_CLASS_NARROWEST_MODE (MODE_INT); tmode != VOIDmode; | |
2168 | tmode = GET_MODE_WIDER_MODE (tmode)) | |
2169 | { | |
2170 | unit = GET_MODE_BITSIZE (tmode); | |
2171 | if (bitpos / unit == (bitpos + bitsize - 1) / unit | |
2172 | && unit <= BITS_PER_WORD | |
770ae6cc | 2173 | && unit <= MIN (align, BIGGEST_ALIGNMENT) |
77fa0940 RK |
2174 | && (largest_mode == VOIDmode |
2175 | || unit <= GET_MODE_BITSIZE (largest_mode))) | |
2176 | wide_mode = tmode; | |
2177 | } | |
2178 | ||
2179 | if (wide_mode != VOIDmode) | |
2180 | return wide_mode; | |
2181 | } | |
7306ed3f JW |
2182 | |
2183 | return mode; | |
2184 | } | |
d7db6646 | 2185 | |
50654f6c | 2186 | /* Gets minimal and maximal values for MODE (signed or unsigned depending on |
0aea6467 | 2187 | SIGN). The returned constants are made to be usable in TARGET_MODE. */ |
50654f6c ZD |
2188 | |
2189 | void | |
0aea6467 ZD |
2190 | get_mode_bounds (enum machine_mode mode, int sign, |
2191 | enum machine_mode target_mode, | |
2192 | rtx *mmin, rtx *mmax) | |
50654f6c | 2193 | { |
0aea6467 ZD |
2194 | unsigned size = GET_MODE_BITSIZE (mode); |
2195 | unsigned HOST_WIDE_INT min_val, max_val; | |
50654f6c | 2196 | |
41374e13 | 2197 | gcc_assert (size <= HOST_BITS_PER_WIDE_INT); |
50654f6c ZD |
2198 | |
2199 | if (sign) | |
2200 | { | |
0aea6467 ZD |
2201 | min_val = -((unsigned HOST_WIDE_INT) 1 << (size - 1)); |
2202 | max_val = ((unsigned HOST_WIDE_INT) 1 << (size - 1)) - 1; | |
50654f6c ZD |
2203 | } |
2204 | else | |
2205 | { | |
0aea6467 ZD |
2206 | min_val = 0; |
2207 | max_val = ((unsigned HOST_WIDE_INT) 1 << (size - 1) << 1) - 1; | |
50654f6c | 2208 | } |
0aea6467 | 2209 | |
bb80db7b KH |
2210 | *mmin = gen_int_mode (min_val, target_mode); |
2211 | *mmax = gen_int_mode (max_val, target_mode); | |
50654f6c ZD |
2212 | } |
2213 | ||
e2500fed | 2214 | #include "gt-stor-layout.h" |