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9bf86ebb PR |
1 | /* Output variables, constants and external declarations, for GNU compiler. |
2 | Copyright (C) 1987, 1988, 1989, 1992, 1993 Free Software Foundation, Inc. | |
3 | ||
4 | This file is part of GNU CC. | |
5 | ||
6 | GNU CC is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 2, or (at your option) | |
9 | any later version. | |
10 | ||
11 | GNU CC is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GNU CC; see the file COPYING. If not, write to | |
18 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
19 | ||
20 | ||
21 | /* This file handles generation of all the assembler code | |
22 | *except* the instructions of a function. | |
23 | This includes declarations of variables and their initial values. | |
24 | ||
25 | We also output the assembler code for constants stored in memory | |
26 | and are responsible for combining constants with the same value. */ | |
27 | ||
28 | #include <stdio.h> | |
29 | #include <setjmp.h> | |
30 | /* #include <stab.h> */ | |
31 | #include "config.h" | |
32 | #include "rtl.h" | |
33 | #include "tree.h" | |
34 | #include "flags.h" | |
35 | #include "function.h" | |
36 | #include "expr.h" | |
37 | #include "hard-reg-set.h" | |
38 | #include "regs.h" | |
39 | #include "defaults.h" | |
40 | #include "real.h" | |
41 | ||
42 | #include "obstack.h" | |
43 | ||
44 | #ifdef XCOFF_DEBUGGING_INFO | |
45 | #include "xcoffout.h" | |
46 | #endif | |
47 | ||
48 | #ifndef ASM_STABS_OP | |
49 | #define ASM_STABS_OP ".stabs" | |
50 | #endif | |
51 | ||
52 | /* This macro gets just the user-specified name | |
53 | out of the string in a SYMBOL_REF. On most machines, | |
54 | we discard the * if any and that's all. */ | |
55 | #ifndef STRIP_NAME_ENCODING | |
56 | #define STRIP_NAME_ENCODING(VAR,SYMBOL_NAME) \ | |
57 | (VAR) = ((SYMBOL_NAME) + ((SYMBOL_NAME)[0] == '*')) | |
58 | #endif | |
59 | ||
60 | /* File in which assembler code is being written. */ | |
61 | ||
62 | extern FILE *asm_out_file; | |
63 | ||
64 | /* The (assembler) name of the first globally-visible object output. */ | |
65 | char *first_global_object_name; | |
66 | ||
67 | extern struct obstack *current_obstack; | |
68 | extern struct obstack *saveable_obstack; | |
69 | extern struct obstack permanent_obstack; | |
70 | #define obstack_chunk_alloc xmalloc | |
71 | ||
72 | /* Number for making the label on the next | |
73 | constant that is stored in memory. */ | |
74 | ||
75 | int const_labelno; | |
76 | ||
77 | /* Number for making the label on the next | |
78 | static variable internal to a function. */ | |
79 | ||
80 | int var_labelno; | |
81 | ||
82 | /* Nonzero if at least one function definition has been seen. */ | |
83 | static int function_defined; | |
84 | ||
85 | extern FILE *asm_out_file; | |
86 | ||
87 | static char *compare_constant_1 (); | |
88 | static void record_constant_1 (); | |
89 | void output_constant_pool (); | |
90 | void assemble_name (); | |
91 | int output_addressed_constants (); | |
92 | void output_constant (); | |
93 | void output_constructor (); | |
94 | void text_section (); | |
95 | void readonly_data_section (); | |
96 | void data_section (); | |
97 | \f | |
98 | #ifdef EXTRA_SECTIONS | |
99 | static enum in_section {no_section, in_text, in_data, EXTRA_SECTIONS} in_section | |
100 | = no_section; | |
101 | #else | |
102 | static enum in_section {no_section, in_text, in_data} in_section | |
103 | = no_section; | |
104 | #endif | |
105 | ||
106 | /* Define functions like text_section for any extra sections. */ | |
107 | #ifdef EXTRA_SECTION_FUNCTIONS | |
108 | EXTRA_SECTION_FUNCTIONS | |
109 | #endif | |
110 | ||
111 | /* Tell assembler to switch to text section. */ | |
112 | ||
113 | void | |
114 | text_section () | |
115 | { | |
116 | if (in_section != in_text) | |
117 | { | |
118 | fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP); | |
119 | in_section = in_text; | |
120 | } | |
121 | } | |
122 | ||
123 | /* Tell assembler to switch to data section. */ | |
124 | ||
125 | void | |
126 | data_section () | |
127 | { | |
128 | if (in_section != in_data) | |
129 | { | |
130 | if (flag_shared_data) | |
131 | { | |
132 | #ifdef SHARED_SECTION_ASM_OP | |
133 | fprintf (asm_out_file, "%s\n", SHARED_SECTION_ASM_OP); | |
134 | #else | |
135 | fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP); | |
136 | #endif | |
137 | } | |
138 | else | |
139 | fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP); | |
140 | ||
141 | in_section = in_data; | |
142 | } | |
143 | } | |
144 | ||
145 | /* Tell assembler to switch to read-only data section. This is normally | |
146 | the text section. */ | |
147 | ||
148 | void | |
149 | readonly_data_section () | |
150 | { | |
151 | #ifdef READONLY_DATA_SECTION | |
152 | READONLY_DATA_SECTION (); /* Note this can call data_section. */ | |
153 | #else | |
154 | text_section (); | |
155 | #endif | |
156 | } | |
157 | ||
158 | /* Determine if we're in the text section. */ | |
159 | ||
160 | int | |
161 | in_text_section () | |
162 | { | |
163 | return in_section == in_text; | |
164 | } | |
165 | \f | |
166 | /* Create the rtl to represent a function, for a function definition. | |
167 | DECL is a FUNCTION_DECL node which describes which function. | |
168 | The rtl is stored into DECL. */ | |
169 | ||
170 | void | |
171 | make_function_rtl (decl) | |
172 | tree decl; | |
173 | { | |
174 | char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); | |
175 | ||
176 | /* Rename a nested function to avoid conflicts. */ | |
177 | if (decl_function_context (decl) != 0 | |
178 | && DECL_INITIAL (decl) != 0 | |
179 | && DECL_RTL (decl) == 0) | |
180 | { | |
181 | char *label; | |
182 | ||
183 | name = IDENTIFIER_POINTER (DECL_NAME (decl)); | |
184 | ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno); | |
185 | name = obstack_copy0 (saveable_obstack, label, strlen (label)); | |
186 | var_labelno++; | |
187 | } | |
188 | ||
189 | if (DECL_RTL (decl) == 0) | |
190 | { | |
191 | DECL_RTL (decl) | |
192 | = gen_rtx (MEM, DECL_MODE (decl), | |
193 | gen_rtx (SYMBOL_REF, Pmode, name)); | |
194 | ||
195 | /* Optionally set flags or add text to the name to record information | |
196 | such as that it is a function name. If the name is changed, the macro | |
197 | ASM_OUTPUT_LABELREF will have to know how to strip this information. | |
198 | And if it finds a * at the beginning after doing so, it must handle | |
199 | that too. */ | |
200 | #ifdef ENCODE_SECTION_INFO | |
201 | ENCODE_SECTION_INFO (decl); | |
202 | #endif | |
203 | } | |
204 | ||
205 | /* Record at least one function has been defined. */ | |
206 | function_defined = 1; | |
207 | } | |
208 | ||
209 | /* Given NAME, a putative register name, discard any customary prefixes. */ | |
210 | ||
211 | static char * | |
212 | strip_reg_name (name) | |
213 | char *name; | |
214 | { | |
215 | #ifdef REGISTER_PREFIX | |
216 | if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX))) | |
217 | name += strlen (REGISTER_PREFIX); | |
218 | #endif | |
219 | if (name[0] == '%' || name[0] == '#') | |
220 | name++; | |
221 | return name; | |
222 | } | |
223 | \f | |
224 | /* Decode an `asm' spec for a declaration as a register name. | |
225 | Return the register number, or -1 if nothing specified, | |
226 | or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized, | |
227 | or -3 if ASMSPEC is `cc' and is not recognized, | |
228 | or -4 if ASMSPEC is `memory' and is not recognized. | |
229 | Accept an exact spelling or a decimal number. | |
230 | Prefixes such as % are optional. */ | |
231 | ||
232 | int | |
233 | decode_reg_name (asmspec) | |
234 | char *asmspec; | |
235 | { | |
236 | if (asmspec != 0) | |
237 | { | |
238 | int i; | |
239 | ||
240 | /* Get rid of confusing prefixes. */ | |
241 | asmspec = strip_reg_name (asmspec); | |
242 | ||
243 | /* Allow a decimal number as a "register name". */ | |
244 | for (i = strlen (asmspec) - 1; i >= 0; i--) | |
245 | if (! (asmspec[i] >= '0' && asmspec[i] <= '9')) | |
246 | break; | |
247 | if (asmspec[0] != 0 && i < 0) | |
248 | { | |
249 | i = atoi (asmspec); | |
250 | if (i < FIRST_PSEUDO_REGISTER && i >= 0) | |
251 | return i; | |
252 | else | |
253 | return -2; | |
254 | } | |
255 | ||
256 | for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) | |
257 | if (reg_names[i][0] | |
258 | && ! strcmp (asmspec, strip_reg_name (reg_names[i]))) | |
259 | return i; | |
260 | ||
261 | #ifdef ADDITIONAL_REGISTER_NAMES | |
262 | { | |
263 | static struct { char *name; int number; } table[] | |
264 | = ADDITIONAL_REGISTER_NAMES; | |
265 | ||
266 | for (i = 0; i < sizeof (table) / sizeof (table[0]); i++) | |
267 | if (! strcmp (asmspec, table[i].name)) | |
268 | return table[i].number; | |
269 | } | |
270 | #endif /* ADDITIONAL_REGISTER_NAMES */ | |
271 | ||
272 | if (!strcmp (asmspec, "memory")) | |
273 | return -4; | |
274 | ||
275 | if (!strcmp (asmspec, "cc")) | |
276 | return -3; | |
277 | ||
278 | return -2; | |
279 | } | |
280 | ||
281 | return -1; | |
282 | } | |
283 | \f | |
284 | /* Create the DECL_RTL for a declaration for a static or external variable | |
285 | or static or external function. | |
286 | ASMSPEC, if not 0, is the string which the user specified | |
287 | as the assembler symbol name. | |
288 | TOP_LEVEL is nonzero if this is a file-scope variable. | |
289 | ||
290 | This is never called for PARM_DECL nodes. */ | |
291 | ||
292 | void | |
293 | make_decl_rtl (decl, asmspec, top_level) | |
294 | tree decl; | |
295 | char *asmspec; | |
296 | int top_level; | |
297 | { | |
298 | register char *name; | |
299 | int reg_number = decode_reg_name (asmspec); | |
300 | ||
301 | if (DECL_ASSEMBLER_NAME (decl) != NULL_TREE) | |
302 | name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); | |
303 | ||
304 | if (reg_number == -2) | |
305 | { | |
306 | /* ASMSPEC is given, and not the name of a register. */ | |
307 | name = (char *) obstack_alloc (saveable_obstack, | |
308 | strlen (asmspec) + 2); | |
309 | name[0] = '*'; | |
310 | strcpy (&name[1], asmspec); | |
311 | } | |
312 | ||
313 | /* For a duplicate declaration, we can be called twice on the | |
314 | same DECL node. Don't alter the RTL already made | |
315 | unless the old mode is wrong (which can happen when | |
316 | the previous rtl was made when the type was incomplete). */ | |
317 | if (DECL_RTL (decl) == 0 | |
318 | || GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl)) | |
319 | { | |
320 | DECL_RTL (decl) = 0; | |
321 | ||
322 | /* First detect errors in declaring global registers. */ | |
323 | if (DECL_REGISTER (decl) && reg_number == -1) | |
324 | error_with_decl (decl, | |
325 | "register name not specified for `%s'"); | |
326 | else if (DECL_REGISTER (decl) && reg_number < 0) | |
327 | error_with_decl (decl, | |
328 | "invalid register name for `%s'"); | |
329 | else if ((reg_number >= 0 || reg_number == -3) && ! DECL_REGISTER (decl)) | |
330 | error_with_decl (decl, | |
331 | "register name given for non-register variable `%s'"); | |
332 | else if (DECL_REGISTER (decl) && TREE_CODE (decl) == FUNCTION_DECL) | |
333 | error ("function declared `register'"); | |
334 | else if (DECL_REGISTER (decl) && TYPE_MODE (TREE_TYPE (decl)) == BLKmode) | |
335 | error_with_decl (decl, "data type of `%s' isn't suitable for a register"); | |
336 | else if (DECL_REGISTER (decl) | |
337 | && ! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl)))) | |
338 | error_with_decl (decl, "register number for `%s' isn't suitable for the data type"); | |
339 | /* Now handle properly declared static register variables. */ | |
340 | else if (DECL_REGISTER (decl)) | |
341 | { | |
342 | int nregs; | |
343 | #if 0 /* yylex should print the warning for this */ | |
344 | if (pedantic) | |
345 | pedwarn ("ANSI C forbids global register variables"); | |
346 | #endif | |
347 | if (DECL_INITIAL (decl) != 0 && top_level) | |
348 | { | |
349 | DECL_INITIAL (decl) = 0; | |
350 | error ("global register variable has initial value"); | |
351 | } | |
352 | if (fixed_regs[reg_number] == 0 | |
353 | && function_defined && top_level) | |
354 | error ("global register variable follows a function definition"); | |
355 | if (TREE_THIS_VOLATILE (decl)) | |
356 | warning ("volatile register variables don't work as you might wish"); | |
357 | ||
358 | /* If the user specified one of the eliminables registers here, | |
359 | e.g., FRAME_POINTER_REGNUM, we don't want to get this variable | |
360 | confused with that register and be eliminated. Although this | |
361 | usage is somewhat suspect, we nevertheless use the following | |
362 | kludge to avoid setting DECL_RTL to frame_pointer_rtx. */ | |
363 | ||
364 | DECL_RTL (decl) | |
365 | = gen_rtx (REG, DECL_MODE (decl), FIRST_PSEUDO_REGISTER); | |
366 | REGNO (DECL_RTL (decl)) = reg_number; | |
367 | REG_USERVAR_P (DECL_RTL (decl)) = 1; | |
368 | ||
369 | if (top_level) | |
370 | { | |
371 | /* Make this register fixed, so not usable for anything else. */ | |
372 | nregs = HARD_REGNO_NREGS (reg_number, DECL_MODE (decl)); | |
373 | while (nregs > 0) | |
374 | global_regs[reg_number + --nregs] = 1; | |
375 | init_reg_sets_1 (); | |
376 | } | |
377 | } | |
378 | ||
379 | /* Now handle ordinary static variables and functions (in memory). | |
380 | Also handle vars declared register invalidly. */ | |
381 | if (DECL_RTL (decl) == 0) | |
382 | { | |
383 | /* Can't use just the variable's own name for a variable | |
384 | whose scope is less than the whole file. | |
385 | Concatenate a distinguishing number. */ | |
386 | if (!top_level && !DECL_EXTERNAL (decl) && asmspec == 0) | |
387 | { | |
388 | char *label; | |
389 | ||
390 | ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno); | |
391 | name = obstack_copy0 (saveable_obstack, label, strlen (label)); | |
392 | var_labelno++; | |
393 | } | |
394 | ||
395 | DECL_RTL (decl) = gen_rtx (MEM, DECL_MODE (decl), | |
396 | gen_rtx (SYMBOL_REF, Pmode, name)); | |
397 | if (TREE_THIS_VOLATILE (decl) | |
398 | || (flag_volatile_global && TREE_CODE (decl) == VAR_DECL | |
399 | && TREE_PUBLIC (decl))) | |
400 | MEM_VOLATILE_P (DECL_RTL (decl)) = 1; | |
401 | if (TREE_READONLY (decl)) | |
402 | RTX_UNCHANGING_P (DECL_RTL (decl)) = 1; | |
403 | MEM_IN_STRUCT_P (DECL_RTL (decl)) | |
404 | = (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE | |
405 | || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE | |
406 | || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE | |
407 | || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE); | |
408 | ||
409 | /* Optionally set flags or add text to the name to record information | |
410 | such as that it is a function name. | |
411 | If the name is changed, the macro ASM_OUTPUT_LABELREF | |
412 | will have to know how to strip this information. | |
413 | And if it finds a * at the beginning after doing so, | |
414 | it must handle that too. */ | |
415 | #ifdef ENCODE_SECTION_INFO | |
416 | ENCODE_SECTION_INFO (decl); | |
417 | #endif | |
418 | } | |
419 | } | |
420 | } | |
421 | ||
422 | /* Make the rtl for variable VAR be volatile. | |
423 | Use this only for static variables. */ | |
424 | ||
425 | void | |
426 | make_var_volatile (var) | |
427 | tree var; | |
428 | { | |
429 | if (GET_CODE (DECL_RTL (var)) != MEM) | |
430 | abort (); | |
431 | ||
432 | MEM_VOLATILE_P (DECL_RTL (var)) = 1; | |
433 | } | |
434 | \f | |
435 | /* Output alignment directive to align for constant expression EXP. */ | |
436 | ||
437 | void | |
438 | assemble_constant_align (exp) | |
439 | tree exp; | |
440 | { | |
441 | int align; | |
442 | ||
443 | /* Align the location counter as required by EXP's data type. */ | |
444 | align = TYPE_ALIGN (TREE_TYPE (exp)); | |
445 | #ifdef CONSTANT_ALIGNMENT | |
446 | align = CONSTANT_ALIGNMENT (exp, align); | |
447 | #endif | |
448 | ||
449 | if (align > BITS_PER_UNIT) | |
450 | ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); | |
451 | } | |
452 | ||
453 | /* Output a string of literal assembler code | |
454 | for an `asm' keyword used between functions. */ | |
455 | ||
456 | void | |
457 | assemble_asm (string) | |
458 | tree string; | |
459 | { | |
460 | app_enable (); | |
461 | ||
462 | if (TREE_CODE (string) == ADDR_EXPR) | |
463 | string = TREE_OPERAND (string, 0); | |
464 | ||
465 | fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string)); | |
466 | } | |
467 | ||
468 | #if 0 /* This should no longer be needed, because | |
469 | flag_gnu_linker should be 0 on these systems, | |
470 | which should prevent any output | |
471 | if ASM_OUTPUT_CONSTRUCTOR and ASM_OUTPUT_DESTRUCTOR are absent. */ | |
472 | #if !(defined(DBX_DEBUGGING_INFO) && !defined(FASCIST_ASSEMBLER)) | |
473 | #ifndef ASM_OUTPUT_CONSTRUCTOR | |
474 | #define ASM_OUTPUT_CONSTRUCTOR(file, name) | |
475 | #endif | |
476 | #ifndef ASM_OUTPUT_DESTRUCTOR | |
477 | #define ASM_OUTPUT_DESTRUCTOR(file, name) | |
478 | #endif | |
479 | #endif | |
480 | #endif /* 0 */ | |
481 | ||
482 | /* Record an element in the table of global destructors. | |
483 | How this is done depends on what sort of assembler and linker | |
484 | are in use. | |
485 | ||
486 | NAME should be the name of a global function to be called | |
487 | at exit time. This name is output using assemble_name. */ | |
488 | ||
489 | void | |
490 | assemble_destructor (name) | |
491 | char *name; | |
492 | { | |
493 | #ifdef ASM_OUTPUT_DESTRUCTOR | |
494 | ASM_OUTPUT_DESTRUCTOR (asm_out_file, name); | |
495 | #else | |
496 | if (flag_gnu_linker) | |
497 | { | |
498 | /* Now tell GNU LD that this is part of the static destructor set. */ | |
499 | /* This code works for any machine provided you use GNU as/ld. */ | |
500 | fprintf (asm_out_file, "%s \"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP); | |
501 | assemble_name (asm_out_file, name); | |
502 | fputc ('\n', asm_out_file); | |
503 | } | |
504 | #endif | |
505 | } | |
506 | ||
507 | /* Likewise for global constructors. */ | |
508 | ||
509 | void | |
510 | assemble_constructor (name) | |
511 | char *name; | |
512 | { | |
513 | #ifdef ASM_OUTPUT_CONSTRUCTOR | |
514 | ASM_OUTPUT_CONSTRUCTOR (asm_out_file, name); | |
515 | #else | |
516 | if (flag_gnu_linker) | |
517 | { | |
518 | /* Now tell GNU LD that this is part of the static constructor set. */ | |
519 | /* This code works for any machine provided you use GNU as/ld. */ | |
520 | fprintf (asm_out_file, "%s \"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP); | |
521 | assemble_name (asm_out_file, name); | |
522 | fputc ('\n', asm_out_file); | |
523 | } | |
524 | #endif | |
525 | } | |
526 | ||
527 | /* Likewise for entries we want to record for garbage collection. | |
528 | Garbage collection is still under development. */ | |
529 | ||
530 | void | |
531 | assemble_gc_entry (name) | |
532 | char *name; | |
533 | { | |
534 | #ifdef ASM_OUTPUT_GC_ENTRY | |
535 | ASM_OUTPUT_GC_ENTRY (asm_out_file, name); | |
536 | #else | |
537 | if (flag_gnu_linker) | |
538 | { | |
539 | /* Now tell GNU LD that this is part of the static constructor set. */ | |
540 | fprintf (asm_out_file, "%s \"___PTR_LIST__\",22,0,0,", ASM_STABS_OP); | |
541 | assemble_name (asm_out_file, name); | |
542 | fputc ('\n', asm_out_file); | |
543 | } | |
544 | #endif | |
545 | } | |
546 | \f | |
547 | /* Output assembler code for the constant pool of a function and associated | |
548 | with defining the name of the function. DECL describes the function. | |
549 | NAME is the function's name. For the constant pool, we use the current | |
550 | constant pool data. */ | |
551 | ||
552 | void | |
553 | assemble_start_function (decl, fnname) | |
554 | tree decl; | |
555 | char *fnname; | |
556 | { | |
557 | int align; | |
558 | ||
559 | /* The following code does not need preprocessing in the assembler. */ | |
560 | ||
561 | app_disable (); | |
562 | ||
563 | output_constant_pool (fnname, decl); | |
564 | ||
565 | text_section (); | |
566 | ||
567 | ||
568 | /* Tell assembler to move to target machine's alignment for functions. */ | |
569 | align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT); | |
570 | if (align > 0) | |
571 | ASM_OUTPUT_ALIGN (asm_out_file, align); | |
572 | ||
573 | #ifdef ASM_OUTPUT_FUNCTION_PREFIX | |
574 | ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname); | |
575 | #endif | |
576 | ||
577 | #ifdef SDB_DEBUGGING_INFO | |
578 | /* Output SDB definition of the function. */ | |
579 | if (write_symbols == SDB_DEBUG) | |
580 | sdbout_mark_begin_function (); | |
581 | #endif | |
582 | ||
583 | #ifdef DBX_DEBUGGING_INFO | |
584 | /* Output DBX definition of the function. */ | |
585 | if (write_symbols == DBX_DEBUG) | |
586 | dbxout_begin_function (decl); | |
587 | #endif | |
588 | ||
589 | /* Make function name accessible from other files, if appropriate. */ | |
590 | ||
591 | if (TREE_PUBLIC (decl)) | |
592 | { | |
593 | if (!first_global_object_name) | |
594 | STRIP_NAME_ENCODING (first_global_object_name, fnname); | |
595 | ASM_GLOBALIZE_LABEL (asm_out_file, fnname); | |
596 | } | |
597 | ||
598 | /* Do any machine/system dependent processing of the function name */ | |
599 | #ifdef ASM_DECLARE_FUNCTION_NAME | |
600 | ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl); | |
601 | #else | |
602 | /* Standard thing is just output label for the function. */ | |
603 | ASM_OUTPUT_LABEL (asm_out_file, fnname); | |
604 | #endif /* ASM_DECLARE_FUNCTION_NAME */ | |
605 | } | |
606 | ||
607 | /* Output assembler code associated with defining the size of the | |
608 | function. DECL describes the function. NAME is the function's name. */ | |
609 | ||
610 | void | |
611 | assemble_end_function (decl, fnname) | |
612 | tree decl; | |
613 | char *fnname; | |
614 | { | |
615 | #ifdef ASM_DECLARE_FUNCTION_SIZE | |
616 | ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl); | |
617 | #endif | |
618 | } | |
619 | \f | |
620 | /* Assemble code to leave SIZE bytes of zeros. */ | |
621 | ||
622 | void | |
623 | assemble_zeros (size) | |
624 | int size; | |
625 | { | |
626 | #ifdef ASM_NO_SKIP_IN_TEXT | |
627 | /* The `space' pseudo in the text section outputs nop insns rather than 0s, | |
628 | so we must output 0s explicitly in the text section. */ | |
629 | if (ASM_NO_SKIP_IN_TEXT && in_text_section ()) | |
630 | { | |
631 | int i; | |
632 | ||
633 | for (i = 0; i < size - 20; i += 20) | |
634 | { | |
635 | #ifdef ASM_BYTE_OP | |
636 | fprintf (asm_out_file, | |
637 | "%s 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0\n", ASM_BYTE_OP); | |
638 | #else | |
639 | fprintf (asm_out_file, | |
640 | "\tbyte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0\n"); | |
641 | #endif | |
642 | } | |
643 | if (i < size) | |
644 | { | |
645 | #ifdef ASM_BYTE_OP | |
646 | fprintf (asm_out_file, "%s 0", ASM_BYTE_OP); | |
647 | #else | |
648 | fprintf (asm_out_file, "\tbyte 0"); | |
649 | #endif | |
650 | i++; | |
651 | for (; i < size; i++) | |
652 | fprintf (asm_out_file, ",0"); | |
653 | fprintf (asm_out_file, "\n"); | |
654 | } | |
655 | } | |
656 | else | |
657 | #endif | |
658 | if (size > 0) | |
659 | ASM_OUTPUT_SKIP (asm_out_file, size); | |
660 | } | |
661 | ||
662 | /* Assemble a string constant with the specified C string as contents. */ | |
663 | ||
664 | void | |
665 | assemble_string (p, size) | |
666 | char *p; | |
667 | int size; | |
668 | { | |
669 | register int i; | |
670 | int pos = 0; | |
671 | int maximum = 2000; | |
672 | ||
673 | /* If the string is very long, split it up. */ | |
674 | ||
675 | while (pos < size) | |
676 | { | |
677 | int thissize = size - pos; | |
678 | if (thissize > maximum) | |
679 | thissize = maximum; | |
680 | ||
681 | ASM_OUTPUT_ASCII (asm_out_file, p, thissize); | |
682 | ||
683 | pos += thissize; | |
684 | p += thissize; | |
685 | } | |
686 | } | |
687 | \f | |
688 | /* Assemble everything that is needed for a variable or function declaration. | |
689 | Not used for automatic variables, and not used for function definitions. | |
690 | Should not be called for variables of incomplete structure type. | |
691 | ||
692 | TOP_LEVEL is nonzero if this variable has file scope. | |
693 | AT_END is nonzero if this is the special handling, at end of compilation, | |
694 | to define things that have had only tentative definitions. */ | |
695 | ||
696 | void | |
697 | assemble_variable (decl, top_level, at_end) | |
698 | tree decl; | |
699 | int top_level; | |
700 | int at_end; | |
701 | { | |
702 | register char *name; | |
703 | int align; | |
704 | tree size_tree; | |
705 | int reloc = 0; | |
706 | ||
707 | if (GET_CODE (DECL_RTL (decl)) == REG) | |
708 | { | |
709 | /* Do output symbol info for global register variables, but do nothing | |
710 | else for them. */ | |
711 | ||
712 | if (TREE_ASM_WRITTEN (decl)) | |
713 | return; | |
714 | TREE_ASM_WRITTEN (decl) = 1; | |
715 | ||
716 | #if defined (DBX_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO) | |
717 | /* File-scope global variables are output here. */ | |
718 | if ((write_symbols == DBX_DEBUG || write_symbols == XCOFF_DEBUG) | |
719 | && top_level) | |
720 | dbxout_symbol (decl, 0); | |
721 | #endif | |
722 | #ifdef SDB_DEBUGGING_INFO | |
723 | if (write_symbols == SDB_DEBUG && top_level | |
724 | /* Leave initialized global vars for end of compilation; | |
725 | see comment in compile_file. */ | |
726 | && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0)) | |
727 | sdbout_symbol (decl, 0); | |
728 | #endif | |
729 | ||
730 | /* Don't output any DWARF debugging information for variables here. | |
731 | In the case of local variables, the information for them is output | |
732 | when we do our recursive traversal of the tree representation for | |
733 | the entire containing function. In the case of file-scope variables, | |
734 | we output information for all of them at the very end of compilation | |
735 | while we are doing our final traversal of the chain of file-scope | |
736 | declarations. */ | |
737 | ||
738 | return; | |
739 | } | |
740 | ||
741 | /* Normally no need to say anything here for external references, | |
742 | since assemble_external is called by the langauge-specific code | |
743 | when a declaration is first seen. */ | |
744 | ||
745 | if (DECL_EXTERNAL (decl)) | |
746 | return; | |
747 | ||
748 | /* Output no assembler code for a function declaration. | |
749 | Only definitions of functions output anything. */ | |
750 | ||
751 | if (TREE_CODE (decl) == FUNCTION_DECL) | |
752 | return; | |
753 | ||
754 | /* If type was incomplete when the variable was declared, | |
755 | see if it is complete now. */ | |
756 | ||
757 | if (DECL_SIZE (decl) == 0) | |
758 | layout_decl (decl, 0); | |
759 | ||
760 | /* Still incomplete => don't allocate it; treat the tentative defn | |
761 | (which is what it must have been) as an `extern' reference. */ | |
762 | ||
763 | if (DECL_SIZE (decl) == 0) | |
764 | { | |
765 | error_with_file_and_line (DECL_SOURCE_FILE (decl), | |
766 | DECL_SOURCE_LINE (decl), | |
767 | "storage size of `%s' isn't known", | |
768 | IDENTIFIER_POINTER (DECL_NAME (decl))); | |
769 | return; | |
770 | } | |
771 | ||
772 | /* The first declaration of a variable that comes through this function | |
773 | decides whether it is global (in C, has external linkage) | |
774 | or local (in C, has internal linkage). So do nothing more | |
775 | if this function has already run. */ | |
776 | ||
777 | if (TREE_ASM_WRITTEN (decl)) | |
778 | return; | |
779 | ||
780 | TREE_ASM_WRITTEN (decl) = 1; | |
781 | ||
782 | #ifdef DBX_DEBUGGING_INFO | |
783 | /* File-scope global variables are output here. */ | |
784 | if (write_symbols == DBX_DEBUG && top_level) | |
785 | dbxout_symbol (decl, 0); | |
786 | #endif | |
787 | #ifdef SDB_DEBUGGING_INFO | |
788 | if (write_symbols == SDB_DEBUG && top_level | |
789 | /* Leave initialized global vars for end of compilation; | |
790 | see comment in compile_file. */ | |
791 | && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0)) | |
792 | sdbout_symbol (decl, 0); | |
793 | #endif | |
794 | ||
795 | /* Don't output any DWARF debugging information for variables here. | |
796 | In the case of local variables, the information for them is output | |
797 | when we do our recursive traversal of the tree representation for | |
798 | the entire containing function. In the case of file-scope variables, | |
799 | we output information for all of them at the very end of compilation | |
800 | while we are doing our final traversal of the chain of file-scope | |
801 | declarations. */ | |
802 | ||
803 | /* If storage size is erroneously variable, just continue. | |
804 | Error message was already made. */ | |
805 | ||
806 | if (TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST) | |
807 | goto finish; | |
808 | ||
809 | app_disable (); | |
810 | ||
811 | /* This is better than explicit arithmetic, since it avoids overflow. */ | |
812 | size_tree = size_binop (CEIL_DIV_EXPR, | |
813 | DECL_SIZE (decl), size_int (BITS_PER_UNIT)); | |
814 | ||
815 | if (TREE_INT_CST_HIGH (size_tree) != 0) | |
816 | { | |
817 | error_with_decl (decl, "size of variable `%s' is too large"); | |
818 | goto finish; | |
819 | } | |
820 | ||
821 | name = XSTR (XEXP (DECL_RTL (decl), 0), 0); | |
822 | ||
823 | /* Handle uninitialized definitions. */ | |
824 | ||
825 | /* ANSI specifies that a tentative definition which is not merged with | |
826 | a non-tentative definition behaves exactly like a definition with an | |
827 | initializer equal to zero. (Section 3.7.2) | |
828 | -fno-common gives strict ANSI behavior. Usually you don't want it. */ | |
829 | if (! flag_no_common | |
830 | && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node)) | |
831 | { | |
832 | int size = TREE_INT_CST_LOW (size_tree); | |
833 | int rounded = size; | |
834 | ||
835 | if (TREE_INT_CST_HIGH (size_tree) != 0) | |
836 | error_with_decl (decl, "size of variable `%s' is too large"); | |
837 | /* Don't allocate zero bytes of common, | |
838 | since that means "undefined external" in the linker. */ | |
839 | if (size == 0) rounded = 1; | |
840 | /* Round size up to multiple of BIGGEST_ALIGNMENT bits | |
841 | so that each uninitialized object starts on such a boundary. */ | |
842 | rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1; | |
843 | rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) | |
844 | * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); | |
845 | #if 0 | |
846 | if (flag_shared_data) | |
847 | data_section (); | |
848 | #endif | |
849 | if (TREE_PUBLIC (decl)) | |
850 | { | |
851 | #ifdef ASM_OUTPUT_SHARED_COMMON | |
852 | if (flag_shared_data) | |
853 | ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded); | |
854 | else | |
855 | #endif | |
856 | #ifdef ASM_OUTPUT_ALIGNED_COMMON | |
857 | ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, | |
858 | DECL_ALIGN (decl)); | |
859 | #else | |
860 | ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded); | |
861 | #endif | |
862 | } | |
863 | else | |
864 | { | |
865 | #ifdef ASM_OUTPUT_SHARED_LOCAL | |
866 | if (flag_shared_data) | |
867 | ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded); | |
868 | else | |
869 | #endif | |
870 | #ifdef ASM_OUTPUT_ALIGNED_LOCAL | |
871 | ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, | |
872 | DECL_ALIGN (decl)); | |
873 | #else | |
874 | ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded); | |
875 | #endif | |
876 | } | |
877 | goto finish; | |
878 | } | |
879 | ||
880 | /* Handle initialized definitions. */ | |
881 | ||
882 | /* First make the assembler name(s) global if appropriate. */ | |
883 | if (TREE_PUBLIC (decl) && DECL_NAME (decl)) | |
884 | { | |
885 | if (!first_global_object_name) | |
886 | STRIP_NAME_ENCODING(first_global_object_name, name); | |
887 | ASM_GLOBALIZE_LABEL (asm_out_file, name); | |
888 | } | |
889 | #if 0 | |
890 | for (d = equivalents; d; d = TREE_CHAIN (d)) | |
891 | { | |
892 | tree e = TREE_VALUE (d); | |
893 | if (TREE_PUBLIC (e) && DECL_NAME (e)) | |
894 | ASM_GLOBALIZE_LABEL (asm_out_file, | |
895 | XSTR (XEXP (DECL_RTL (e), 0), 0)); | |
896 | } | |
897 | #endif | |
898 | ||
899 | /* Output any data that we will need to use the address of. */ | |
900 | if (DECL_INITIAL (decl)) | |
901 | reloc = output_addressed_constants (DECL_INITIAL (decl)); | |
902 | ||
903 | /* Switch to the proper section for this data. */ | |
904 | #ifdef SELECT_SECTION | |
905 | SELECT_SECTION (decl, reloc); | |
906 | #else | |
907 | if (TREE_READONLY (decl) | |
908 | && ! TREE_THIS_VOLATILE (decl) | |
909 | && ! (flag_pic && reloc)) | |
910 | readonly_data_section (); | |
911 | else | |
912 | data_section (); | |
913 | #endif | |
914 | ||
915 | /* Compute and output the alignment of this data. */ | |
916 | ||
917 | align = DECL_ALIGN (decl); | |
918 | /* Some object file formats have a maximum alignment which they support. | |
919 | In particular, a.out format supports a maximum alignment of 4. */ | |
920 | #ifndef MAX_OFILE_ALIGNMENT | |
921 | #define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT | |
922 | #endif | |
923 | if (align > MAX_OFILE_ALIGNMENT) | |
924 | { | |
925 | warning_with_decl (decl, | |
926 | "alignment of `%s' is greater than maximum object file alignment"); | |
927 | align = MAX_OFILE_ALIGNMENT; | |
928 | } | |
929 | #ifdef DATA_ALIGNMENT | |
930 | /* On some machines, it is good to increase alignment sometimes. */ | |
931 | align = DATA_ALIGNMENT (TREE_TYPE (decl), align); | |
932 | #endif | |
933 | #ifdef CONSTANT_ALIGNMENT | |
934 | if (DECL_INITIAL (decl)) | |
935 | align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align); | |
936 | #endif | |
937 | ||
938 | /* Reset the alignment in case we have made it tighter, so we can benefit | |
939 | from it in get_pointer_alignment. */ | |
940 | DECL_ALIGN (decl) = align; | |
941 | ||
942 | if (align > BITS_PER_UNIT) | |
943 | ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); | |
944 | ||
945 | /* Do any machine/system dependent processing of the object. */ | |
946 | #ifdef ASM_DECLARE_OBJECT_NAME | |
947 | ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl); | |
948 | #else | |
949 | /* Standard thing is just output label for the object. */ | |
950 | ASM_OUTPUT_LABEL (asm_out_file, name); | |
951 | #endif /* ASM_DECLARE_OBJECT_NAME */ | |
952 | ||
953 | #if 0 | |
954 | for (d = equivalents; d; d = TREE_CHAIN (d)) | |
955 | { | |
956 | tree e = TREE_VALUE (d); | |
957 | ASM_OUTPUT_LABEL (asm_out_file, XSTR (XEXP (DECL_RTL (e), 0), 0)); | |
958 | } | |
959 | #endif | |
960 | ||
961 | if (DECL_INITIAL (decl)) | |
962 | /* Output the actual data. */ | |
963 | output_constant (DECL_INITIAL (decl), | |
964 | int_size_in_bytes (TREE_TYPE (decl))); | |
965 | else | |
966 | /* Leave space for it. */ | |
967 | assemble_zeros (int_size_in_bytes (TREE_TYPE (decl))); | |
968 | ||
969 | finish: | |
970 | #ifdef XCOFF_DEBUGGING_INFO | |
971 | /* Unfortunately, the IBM assembler cannot handle stabx before the actual | |
972 | declaration. When something like ".stabx "aa:S-2",aa,133,0" is emitted | |
973 | and `aa' hasn't been output yet, the assembler generates a stab entry with | |
974 | a value of zero, in addition to creating an unnecessary external entry | |
975 | for `aa'. Hence, we must postpone dbxout_symbol to here at the end. */ | |
976 | ||
977 | /* File-scope global variables are output here. */ | |
978 | if (write_symbols == XCOFF_DEBUG && top_level) | |
979 | dbxout_symbol (decl, 0); | |
980 | #else | |
981 | /* There must be a statement after a label. */ | |
982 | ; | |
983 | #endif | |
984 | } | |
985 | ||
986 | /* Output something to declare an external symbol to the assembler. | |
987 | (Most assemblers don't need this, so we normally output nothing.) | |
988 | Do nothing if DECL is not external. */ | |
989 | ||
990 | void | |
991 | assemble_external (decl) | |
992 | tree decl; | |
993 | { | |
994 | #ifdef ASM_OUTPUT_EXTERNAL | |
995 | if (TREE_CODE_CLASS (TREE_CODE (decl)) == 'd' | |
996 | && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl)) | |
997 | { | |
998 | rtx rtl = DECL_RTL (decl); | |
999 | ||
1000 | if (GET_CODE (rtl) == MEM && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF | |
1001 | && ! SYMBOL_REF_USED (XEXP (rtl, 0))) | |
1002 | { | |
1003 | /* Some systems do require some output. */ | |
1004 | SYMBOL_REF_USED (XEXP (rtl, 0)) = 1; | |
1005 | ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0)); | |
1006 | } | |
1007 | } | |
1008 | #endif | |
1009 | } | |
1010 | ||
1011 | /* Similar, for calling a library function FUN. */ | |
1012 | ||
1013 | void | |
1014 | assemble_external_libcall (fun) | |
1015 | rtx fun; | |
1016 | { | |
1017 | #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL | |
1018 | /* Declare library function name external when first used, if nec. */ | |
1019 | if (! SYMBOL_REF_USED (fun)) | |
1020 | { | |
1021 | SYMBOL_REF_USED (fun) = 1; | |
1022 | ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file, fun); | |
1023 | } | |
1024 | #endif | |
1025 | } | |
1026 | ||
1027 | /* Declare the label NAME global. */ | |
1028 | ||
1029 | void | |
1030 | assemble_global (name) | |
1031 | char *name; | |
1032 | { | |
1033 | ASM_GLOBALIZE_LABEL (asm_out_file, name); | |
1034 | } | |
1035 | ||
1036 | /* Assemble a label named NAME. */ | |
1037 | ||
1038 | void | |
1039 | assemble_label (name) | |
1040 | char *name; | |
1041 | { | |
1042 | ASM_OUTPUT_LABEL (asm_out_file, name); | |
1043 | } | |
1044 | ||
1045 | /* Output to FILE a reference to the assembler name of a C-level name NAME. | |
1046 | If NAME starts with a *, the rest of NAME is output verbatim. | |
1047 | Otherwise NAME is transformed in an implementation-defined way | |
1048 | (usually by the addition of an underscore). | |
1049 | Many macros in the tm file are defined to call this function. */ | |
1050 | ||
1051 | void | |
1052 | assemble_name (file, name) | |
1053 | FILE *file; | |
1054 | char *name; | |
1055 | { | |
1056 | if (name[0] == '*') | |
1057 | fputs (&name[1], file); | |
1058 | else | |
1059 | ASM_OUTPUT_LABELREF (file, name); | |
1060 | } | |
1061 | ||
1062 | /* Allocate SIZE bytes writable static space with a gensym name | |
1063 | and return an RTX to refer to its address. */ | |
1064 | ||
1065 | rtx | |
1066 | assemble_static_space (size) | |
1067 | int size; | |
1068 | { | |
1069 | char name[12]; | |
1070 | char *namestring; | |
1071 | rtx x; | |
1072 | /* Round size up to multiple of BIGGEST_ALIGNMENT bits | |
1073 | so that each uninitialized object starts on such a boundary. */ | |
1074 | int rounded = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1) | |
1075 | / (BIGGEST_ALIGNMENT / BITS_PER_UNIT) | |
1076 | * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); | |
1077 | ||
1078 | #if 0 | |
1079 | if (flag_shared_data) | |
1080 | data_section (); | |
1081 | #endif | |
1082 | ||
1083 | ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno); | |
1084 | ++const_labelno; | |
1085 | ||
1086 | namestring = (char *) obstack_alloc (saveable_obstack, | |
1087 | strlen (name) + 2); | |
1088 | strcpy (namestring, name); | |
1089 | ||
1090 | x = gen_rtx (SYMBOL_REF, Pmode, namestring); | |
1091 | #ifdef ASM_OUTPUT_ALIGNED_LOCAL | |
1092 | ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT); | |
1093 | #else | |
1094 | ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded); | |
1095 | #endif | |
1096 | return x; | |
1097 | } | |
1098 | ||
1099 | /* Assemble the static constant template for function entry trampolines. | |
1100 | This is done at most once per compilation. | |
1101 | Returns an RTX for the address of the template. */ | |
1102 | ||
1103 | rtx | |
1104 | assemble_trampoline_template () | |
1105 | { | |
1106 | char label[256]; | |
1107 | char *name; | |
1108 | int align; | |
1109 | ||
1110 | /* By default, put trampoline templates in read-only data section. */ | |
1111 | ||
1112 | #ifdef TRAMPOLINE_SECTION | |
1113 | TRAMPOLINE_SECTION (); | |
1114 | #else | |
1115 | readonly_data_section (); | |
1116 | #endif | |
1117 | ||
1118 | /* Write the assembler code to define one. */ | |
1119 | align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT); | |
1120 | if (align > 0) | |
1121 | ASM_OUTPUT_ALIGN (asm_out_file, align); | |
1122 | ||
1123 | ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LTRAMP", 0); | |
1124 | TRAMPOLINE_TEMPLATE (asm_out_file); | |
1125 | ||
1126 | /* Record the rtl to refer to it. */ | |
1127 | ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0); | |
1128 | name | |
1129 | = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label)); | |
1130 | return gen_rtx (SYMBOL_REF, Pmode, name); | |
1131 | } | |
1132 | \f | |
1133 | /* Assemble the integer constant X into an object of SIZE bytes. | |
1134 | X must be either a CONST_INT or CONST_DOUBLE. | |
1135 | ||
1136 | Return 1 if we were able to output the constant, otherwise 0. If FORCE is | |
1137 | non-zero, abort if we can't output the constant. */ | |
1138 | ||
1139 | int | |
1140 | assemble_integer (x, size, force) | |
1141 | rtx x; | |
1142 | int size; | |
1143 | int force; | |
1144 | { | |
1145 | /* First try to use the standard 1, 2, 4, 8, and 16 byte | |
1146 | ASM_OUTPUT... macros. */ | |
1147 | ||
1148 | switch (size) | |
1149 | { | |
1150 | #ifdef ASM_OUTPUT_CHAR | |
1151 | case 1: | |
1152 | ASM_OUTPUT_CHAR (asm_out_file, x); | |
1153 | return 1; | |
1154 | #endif | |
1155 | ||
1156 | #ifdef ASM_OUTPUT_SHORT | |
1157 | case 2: | |
1158 | ASM_OUTPUT_SHORT (asm_out_file, x); | |
1159 | return 1; | |
1160 | #endif | |
1161 | ||
1162 | #ifdef ASM_OUTPUT_INT | |
1163 | case 4: | |
1164 | ASM_OUTPUT_INT (asm_out_file, x); | |
1165 | return 1; | |
1166 | #endif | |
1167 | ||
1168 | #ifdef ASM_OUTPUT_DOUBLE_INT | |
1169 | case 8: | |
1170 | ASM_OUTPUT_DOUBLE_INT (asm_out_file, x); | |
1171 | return 1; | |
1172 | #endif | |
1173 | ||
1174 | #ifdef ASM_OUTPUT_QUADRUPLE_INT | |
1175 | case 16: | |
1176 | ASM_OUTPUT_QUADRUPLE_INT (asm_out_file, x); | |
1177 | return 1; | |
1178 | #endif | |
1179 | } | |
1180 | ||
1181 | /* If we couldn't do it that way, there are two other possibilities: First, | |
1182 | if the machine can output an explicit byte and this is a 1 byte constant, | |
1183 | we can use ASM_OUTPUT_BYTE. */ | |
1184 | ||
1185 | #ifdef ASM_OUTPUT_BYTE | |
1186 | if (size == 1 && GET_CODE (x) == CONST_INT) | |
1187 | { | |
1188 | ASM_OUTPUT_BYTE (asm_out_file, INTVAL (x)); | |
1189 | return 1; | |
1190 | } | |
1191 | #endif | |
1192 | ||
1193 | /* Finally, if SIZE is larger than a single word, try to output the constant | |
1194 | one word at a time. */ | |
1195 | ||
1196 | if (size > UNITS_PER_WORD) | |
1197 | { | |
1198 | int i; | |
1199 | enum machine_mode mode | |
1200 | = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0); | |
1201 | rtx word; | |
1202 | ||
1203 | for (i = 0; i < size / UNITS_PER_WORD; i++) | |
1204 | { | |
1205 | word = operand_subword (x, i, 0, mode); | |
1206 | ||
1207 | if (word == 0) | |
1208 | break; | |
1209 | ||
1210 | if (! assemble_integer (word, UNITS_PER_WORD, 0)) | |
1211 | break; | |
1212 | } | |
1213 | ||
1214 | if (i == size / UNITS_PER_WORD) | |
1215 | return 1; | |
1216 | /* If we output at least one word and then could not finish, | |
1217 | there is no valid way to continue. */ | |
1218 | if (i > 0) | |
1219 | abort (); | |
1220 | } | |
1221 | ||
1222 | if (force) | |
1223 | abort (); | |
1224 | ||
1225 | return 0; | |
1226 | } | |
1227 | \f | |
1228 | /* Assemble the floating-point constant D into an object of size MODE. */ | |
1229 | ||
1230 | void | |
1231 | assemble_real (d, mode) | |
1232 | REAL_VALUE_TYPE d; | |
1233 | enum machine_mode mode; | |
1234 | { | |
1235 | jmp_buf output_constant_handler; | |
1236 | ||
1237 | if (setjmp (output_constant_handler)) | |
1238 | { | |
1239 | error ("floating point trap outputting a constant"); | |
1240 | #ifdef REAL_IS_NOT_DOUBLE | |
1241 | bzero (&d, sizeof d); | |
1242 | d = dconst0; | |
1243 | #else | |
1244 | d = 0; | |
1245 | #endif | |
1246 | } | |
1247 | ||
1248 | set_float_handler (output_constant_handler); | |
1249 | ||
1250 | switch (mode) | |
1251 | { | |
1252 | #ifdef ASM_OUTPUT_BYTE_FLOAT | |
1253 | case QFmode: | |
1254 | ASM_OUTPUT_BYTE_FLOAT (asm_out_file, d); | |
1255 | break; | |
1256 | #endif | |
1257 | #ifdef ASM_OUTPUT_SHORT_FLOAT | |
1258 | case HFmode: | |
1259 | ASM_OUTPUT_SHORT_FLOAT (asm_out_file, d); | |
1260 | break; | |
1261 | #endif | |
1262 | #ifdef ASM_OUTPUT_FLOAT | |
1263 | case SFmode: | |
1264 | ASM_OUTPUT_FLOAT (asm_out_file, d); | |
1265 | break; | |
1266 | #endif | |
1267 | ||
1268 | #ifdef ASM_OUTPUT_DOUBLE | |
1269 | case DFmode: | |
1270 | ASM_OUTPUT_DOUBLE (asm_out_file, d); | |
1271 | break; | |
1272 | #endif | |
1273 | ||
1274 | #ifdef ASM_OUTPUT_LONG_DOUBLE | |
1275 | case XFmode: | |
1276 | case TFmode: | |
1277 | ASM_OUTPUT_LONG_DOUBLE (asm_out_file, d); | |
1278 | break; | |
1279 | #endif | |
1280 | ||
1281 | default: | |
1282 | abort (); | |
1283 | } | |
1284 | ||
1285 | set_float_handler (NULL_PTR); | |
1286 | } | |
1287 | \f | |
1288 | /* Here we combine duplicate floating constants to make | |
1289 | CONST_DOUBLE rtx's, and force those out to memory when necessary. */ | |
1290 | ||
1291 | /* Chain of all CONST_DOUBLE rtx's constructed for the current function. | |
1292 | They are chained through the CONST_DOUBLE_CHAIN. | |
1293 | A CONST_DOUBLE rtx has CONST_DOUBLE_MEM != cc0_rtx iff it is on this chain. | |
1294 | In that case, CONST_DOUBLE_MEM is either a MEM, | |
1295 | or const0_rtx if no MEM has been made for this CONST_DOUBLE yet. | |
1296 | ||
1297 | (CONST_DOUBLE_MEM is used only for top-level functions. | |
1298 | See force_const_mem for explanation.) */ | |
1299 | ||
1300 | static rtx const_double_chain; | |
1301 | ||
1302 | /* Return a CONST_DOUBLE for a value specified as a pair of ints. | |
1303 | For an integer, I0 is the low-order word and I1 is the high-order word. | |
1304 | For a real number, I0 is the word with the low address | |
1305 | and I1 is the word with the high address. */ | |
1306 | ||
1307 | rtx | |
1308 | immed_double_const (i0, i1, mode) | |
1309 | HOST_WIDE_INT i0, i1; | |
1310 | enum machine_mode mode; | |
1311 | { | |
1312 | register rtx r; | |
1313 | int in_current_obstack; | |
1314 | ||
1315 | if (GET_MODE_CLASS (mode) == MODE_INT | |
1316 | || GET_MODE_CLASS (mode) == MODE_PARTIAL_INT) | |
1317 | { | |
1318 | /* We clear out all bits that don't belong in MODE, unless they and our | |
1319 | sign bit are all one. So we get either a reasonable negative value | |
1320 | or a reasonable unsigned value for this mode. */ | |
1321 | int width = GET_MODE_BITSIZE (mode); | |
1322 | if (width < HOST_BITS_PER_WIDE_INT | |
1323 | && ((i0 & ((HOST_WIDE_INT) (-1) << (width - 1))) | |
1324 | != ((HOST_WIDE_INT) (-1) << (width - 1)))) | |
1325 | i0 &= ((HOST_WIDE_INT) 1 << width) - 1, i1 = 0; | |
1326 | else if (width == HOST_BITS_PER_WIDE_INT | |
1327 | && ! (i1 == ~0 && i0 < 0)) | |
1328 | i1 = 0; | |
1329 | else if (width > 2 * HOST_BITS_PER_WIDE_INT) | |
1330 | /* We cannot represent this value as a constant. */ | |
1331 | abort (); | |
1332 | ||
1333 | /* If MODE fits within HOST_BITS_PER_WIDE_INT, always use a CONST_INT. | |
1334 | ||
1335 | ??? Strictly speaking, this is wrong if we create a CONST_INT | |
1336 | for a large unsigned constant with the size of MODE being | |
1337 | HOST_BITS_PER_WIDE_INT and later try to interpret that constant in a | |
1338 | wider mode. In that case we will mis-interpret it as a negative | |
1339 | number. | |
1340 | ||
1341 | Unfortunately, the only alternative is to make a CONST_DOUBLE | |
1342 | for any constant in any mode if it is an unsigned constant larger | |
1343 | than the maximum signed integer in an int on the host. However, | |
1344 | doing this will break everyone that always expects to see a CONST_INT | |
1345 | for SImode and smaller. | |
1346 | ||
1347 | We have always been making CONST_INTs in this case, so nothing new | |
1348 | is being broken. */ | |
1349 | ||
1350 | if (width <= HOST_BITS_PER_WIDE_INT) | |
1351 | i1 = (i0 < 0) ? ~0 : 0; | |
1352 | ||
1353 | /* If this integer fits in one word, return a CONST_INT. */ | |
1354 | if ((i1 == 0 && i0 >= 0) | |
1355 | || (i1 == ~0 && i0 < 0)) | |
1356 | return GEN_INT (i0); | |
1357 | ||
1358 | /* We use VOIDmode for integers. */ | |
1359 | mode = VOIDmode; | |
1360 | } | |
1361 | ||
1362 | /* Search the chain for an existing CONST_DOUBLE with the right value. | |
1363 | If one is found, return it. */ | |
1364 | ||
1365 | for (r = const_double_chain; r; r = CONST_DOUBLE_CHAIN (r)) | |
1366 | if (CONST_DOUBLE_LOW (r) == i0 && CONST_DOUBLE_HIGH (r) == i1 | |
1367 | && GET_MODE (r) == mode) | |
1368 | return r; | |
1369 | ||
1370 | /* No; make a new one and add it to the chain. | |
1371 | ||
1372 | We may be called by an optimizer which may be discarding any memory | |
1373 | allocated during its processing (such as combine and loop). However, | |
1374 | we will be leaving this constant on the chain, so we cannot tolerate | |
1375 | freed memory. So switch to saveable_obstack for this allocation | |
1376 | and then switch back if we were in current_obstack. */ | |
1377 | ||
1378 | push_obstacks_nochange (); | |
1379 | rtl_in_saveable_obstack (); | |
1380 | r = gen_rtx (CONST_DOUBLE, mode, 0, i0, i1); | |
1381 | pop_obstacks (); | |
1382 | ||
1383 | /* Don't touch const_double_chain in nested function; | |
1384 | see force_const_mem. */ | |
1385 | if (outer_function_chain == 0) | |
1386 | { | |
1387 | CONST_DOUBLE_CHAIN (r) = const_double_chain; | |
1388 | const_double_chain = r; | |
1389 | } | |
1390 | ||
1391 | /* Store const0_rtx in mem-slot since this CONST_DOUBLE is on the chain. | |
1392 | Actual use of mem-slot is only through force_const_mem. */ | |
1393 | ||
1394 | CONST_DOUBLE_MEM (r) = const0_rtx; | |
1395 | ||
1396 | return r; | |
1397 | } | |
1398 | ||
1399 | /* Return a CONST_DOUBLE for a specified `double' value | |
1400 | and machine mode. */ | |
1401 | ||
1402 | rtx | |
1403 | immed_real_const_1 (d, mode) | |
1404 | REAL_VALUE_TYPE d; | |
1405 | enum machine_mode mode; | |
1406 | { | |
1407 | union real_extract u; | |
1408 | register rtx r; | |
1409 | int in_current_obstack; | |
1410 | ||
1411 | /* Get the desired `double' value as a sequence of ints | |
1412 | since that is how they are stored in a CONST_DOUBLE. */ | |
1413 | ||
1414 | u.d = d; | |
1415 | ||
1416 | /* Detect special cases. */ | |
1417 | ||
1418 | /* Avoid REAL_VALUES_EQUAL here in order to distinguish minus zero. */ | |
1419 | if (!bcmp (&dconst0, &d, sizeof d)) | |
1420 | return CONST0_RTX (mode); | |
2a5f595d PR |
1421 | /* Check for NaN first, because some ports (specifically the i386) do not |
1422 | emit correct ieee-fp code by default, and thus will generate a core | |
1423 | dump here if we pass a NaN to REAL_VALUES_EQUAL and if REAL_VALUES_EQUAL | |
1424 | does a floating point comparison. */ | |
1425 | else if (! REAL_VALUE_ISNAN (d) && REAL_VALUES_EQUAL (dconst1, d)) | |
9bf86ebb PR |
1426 | return CONST1_RTX (mode); |
1427 | ||
1428 | if (sizeof u == 2 * sizeof (HOST_WIDE_INT)) | |
1429 | return immed_double_const (u.i[0], u.i[1], mode); | |
1430 | ||
1431 | /* The rest of this function handles the case where | |
1432 | a float value requires more than 2 ints of space. | |
1433 | It will be deleted as dead code on machines that don't need it. */ | |
1434 | ||
1435 | /* Search the chain for an existing CONST_DOUBLE with the right value. | |
1436 | If one is found, return it. */ | |
1437 | ||
1438 | for (r = const_double_chain; r; r = CONST_DOUBLE_CHAIN (r)) | |
1439 | if (! bcmp (&CONST_DOUBLE_LOW (r), &u, sizeof u) | |
1440 | && GET_MODE (r) == mode) | |
1441 | return r; | |
1442 | ||
1443 | /* No; make a new one and add it to the chain. | |
1444 | ||
1445 | We may be called by an optimizer which may be discarding any memory | |
1446 | allocated during its processing (such as combine and loop). However, | |
1447 | we will be leaving this constant on the chain, so we cannot tolerate | |
1448 | freed memory. So switch to saveable_obstack for this allocation | |
1449 | and then switch back if we were in current_obstack. */ | |
1450 | ||
1451 | push_obstacks_nochange (); | |
1452 | rtl_in_saveable_obstack (); | |
1453 | r = rtx_alloc (CONST_DOUBLE); | |
1454 | PUT_MODE (r, mode); | |
1455 | bcopy (&u, &CONST_DOUBLE_LOW (r), sizeof u); | |
1456 | pop_obstacks (); | |
1457 | ||
1458 | /* Don't touch const_double_chain in nested function; | |
1459 | see force_const_mem. */ | |
1460 | if (outer_function_chain == 0) | |
1461 | { | |
1462 | CONST_DOUBLE_CHAIN (r) = const_double_chain; | |
1463 | const_double_chain = r; | |
1464 | } | |
1465 | ||
1466 | /* Store const0_rtx in CONST_DOUBLE_MEM since this CONST_DOUBLE is on the | |
1467 | chain, but has not been allocated memory. Actual use of CONST_DOUBLE_MEM | |
1468 | is only through force_const_mem. */ | |
1469 | ||
1470 | CONST_DOUBLE_MEM (r) = const0_rtx; | |
1471 | ||
1472 | return r; | |
1473 | } | |
1474 | ||
1475 | /* Return a CONST_DOUBLE rtx for a value specified by EXP, | |
1476 | which must be a REAL_CST tree node. */ | |
1477 | ||
1478 | rtx | |
1479 | immed_real_const (exp) | |
1480 | tree exp; | |
1481 | { | |
1482 | return immed_real_const_1 (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp))); | |
1483 | } | |
1484 | ||
1485 | /* At the end of a function, forget the memory-constants | |
1486 | previously made for CONST_DOUBLEs. Mark them as not on real_constant_chain. | |
1487 | Also clear out real_constant_chain and clear out all the chain-pointers. */ | |
1488 | ||
1489 | void | |
1490 | clear_const_double_mem () | |
1491 | { | |
1492 | register rtx r, next; | |
1493 | ||
1494 | /* Don't touch CONST_DOUBLE_MEM for nested functions. | |
1495 | See force_const_mem for explanation. */ | |
1496 | if (outer_function_chain != 0) | |
1497 | return; | |
1498 | ||
1499 | for (r = const_double_chain; r; r = next) | |
1500 | { | |
1501 | next = CONST_DOUBLE_CHAIN (r); | |
1502 | CONST_DOUBLE_CHAIN (r) = 0; | |
1503 | CONST_DOUBLE_MEM (r) = cc0_rtx; | |
1504 | } | |
1505 | const_double_chain = 0; | |
1506 | } | |
1507 | \f | |
1508 | /* Given an expression EXP with a constant value, | |
1509 | reduce it to the sum of an assembler symbol and an integer. | |
1510 | Store them both in the structure *VALUE. | |
1511 | Abort if EXP does not reduce. */ | |
1512 | ||
1513 | struct addr_const | |
1514 | { | |
1515 | rtx base; | |
1516 | HOST_WIDE_INT offset; | |
1517 | }; | |
1518 | ||
1519 | static void | |
1520 | decode_addr_const (exp, value) | |
1521 | tree exp; | |
1522 | struct addr_const *value; | |
1523 | { | |
1524 | register tree target = TREE_OPERAND (exp, 0); | |
1525 | register int offset = 0; | |
1526 | register rtx x; | |
1527 | ||
1528 | while (1) | |
1529 | { | |
1530 | if (TREE_CODE (target) == COMPONENT_REF | |
1531 | && (TREE_CODE (DECL_FIELD_BITPOS (TREE_OPERAND (target, 1))) | |
1532 | == INTEGER_CST)) | |
1533 | { | |
1534 | offset += TREE_INT_CST_LOW (DECL_FIELD_BITPOS (TREE_OPERAND (target, 1))) / BITS_PER_UNIT; | |
1535 | target = TREE_OPERAND (target, 0); | |
1536 | } | |
1537 | else if (TREE_CODE (target) == ARRAY_REF) | |
1538 | { | |
1539 | if (TREE_CODE (TREE_OPERAND (target, 1)) != INTEGER_CST | |
1540 | || TREE_CODE (TYPE_SIZE (TREE_TYPE (target))) != INTEGER_CST) | |
1541 | abort (); | |
1542 | offset += ((TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (target))) | |
1543 | * TREE_INT_CST_LOW (TREE_OPERAND (target, 1))) | |
1544 | / BITS_PER_UNIT); | |
1545 | target = TREE_OPERAND (target, 0); | |
1546 | } | |
1547 | else | |
1548 | break; | |
1549 | } | |
1550 | ||
1551 | switch (TREE_CODE (target)) | |
1552 | { | |
1553 | case VAR_DECL: | |
1554 | case FUNCTION_DECL: | |
1555 | x = DECL_RTL (target); | |
1556 | break; | |
1557 | ||
1558 | case LABEL_DECL: | |
1559 | x = gen_rtx (MEM, FUNCTION_MODE, | |
1560 | gen_rtx (LABEL_REF, VOIDmode, | |
1561 | label_rtx (TREE_OPERAND (exp, 0)))); | |
1562 | break; | |
1563 | ||
1564 | case REAL_CST: | |
1565 | case STRING_CST: | |
1566 | case COMPLEX_CST: | |
1567 | case CONSTRUCTOR: | |
1568 | x = TREE_CST_RTL (target); | |
1569 | break; | |
1570 | ||
1571 | default: | |
1572 | abort (); | |
1573 | } | |
1574 | ||
1575 | if (GET_CODE (x) != MEM) | |
1576 | abort (); | |
1577 | x = XEXP (x, 0); | |
1578 | ||
1579 | value->base = x; | |
1580 | value->offset = offset; | |
1581 | } | |
1582 | \f | |
1583 | /* Uniquize all constants that appear in memory. | |
1584 | Each constant in memory thus far output is recorded | |
1585 | in `const_hash_table' with a `struct constant_descriptor' | |
1586 | that contains a polish representation of the value of | |
1587 | the constant. | |
1588 | ||
1589 | We cannot store the trees in the hash table | |
1590 | because the trees may be temporary. */ | |
1591 | ||
1592 | struct constant_descriptor | |
1593 | { | |
1594 | struct constant_descriptor *next; | |
1595 | char *label; | |
1596 | char contents[1]; | |
1597 | }; | |
1598 | ||
1599 | #define HASHBITS 30 | |
1600 | #define MAX_HASH_TABLE 1009 | |
1601 | static struct constant_descriptor *const_hash_table[MAX_HASH_TABLE]; | |
1602 | ||
1603 | /* Compute a hash code for a constant expression. */ | |
1604 | ||
1605 | int | |
1606 | const_hash (exp) | |
1607 | tree exp; | |
1608 | { | |
1609 | register char *p; | |
1610 | register int len, hi, i; | |
1611 | register enum tree_code code = TREE_CODE (exp); | |
1612 | ||
1613 | if (code == INTEGER_CST) | |
1614 | { | |
1615 | p = (char *) &TREE_INT_CST_LOW (exp); | |
1616 | len = 2 * sizeof TREE_INT_CST_LOW (exp); | |
1617 | } | |
1618 | else if (code == REAL_CST) | |
1619 | { | |
1620 | p = (char *) &TREE_REAL_CST (exp); | |
1621 | len = sizeof TREE_REAL_CST (exp); | |
1622 | } | |
1623 | else if (code == STRING_CST) | |
1624 | p = TREE_STRING_POINTER (exp), len = TREE_STRING_LENGTH (exp); | |
1625 | else if (code == COMPLEX_CST) | |
1626 | return const_hash (TREE_REALPART (exp)) * 5 | |
1627 | + const_hash (TREE_IMAGPART (exp)); | |
1628 | else if (code == CONSTRUCTOR) | |
1629 | { | |
1630 | register tree link; | |
1631 | ||
1632 | /* For record type, include the type in the hashing. | |
1633 | We do not do so for array types | |
1634 | because (1) the sizes of the elements are sufficient | |
1635 | and (2) distinct array types can have the same constructor. | |
1636 | Instead, we include the array size because the constructor could | |
1637 | be shorter. */ | |
1638 | if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) | |
1639 | hi = ((HOST_WIDE_INT) TREE_TYPE (exp) & ((1 << HASHBITS) - 1)) | |
1640 | % MAX_HASH_TABLE; | |
1641 | else | |
1642 | hi = ((5 + int_size_in_bytes (TREE_TYPE (exp))) | |
1643 | & ((1 << HASHBITS) - 1)) % MAX_HASH_TABLE; | |
1644 | ||
1645 | for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) | |
1646 | if (TREE_VALUE (link)) | |
1647 | hi = (hi * 603 + const_hash (TREE_VALUE (link))) % MAX_HASH_TABLE; | |
1648 | ||
1649 | return hi; | |
1650 | } | |
1651 | else if (code == ADDR_EXPR) | |
1652 | { | |
1653 | struct addr_const value; | |
1654 | decode_addr_const (exp, &value); | |
1655 | if (GET_CODE (value.base) == SYMBOL_REF) | |
1656 | { | |
1657 | /* Don't hash the address of the SYMBOL_REF; | |
1658 | only use the offset and the symbol name. */ | |
1659 | hi = value.offset; | |
1660 | p = XSTR (value.base, 0); | |
1661 | for (i = 0; p[i] != 0; i++) | |
1662 | hi = ((hi * 613) + (unsigned)(p[i])); | |
1663 | } | |
1664 | else if (GET_CODE (value.base) == LABEL_REF) | |
1665 | hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13; | |
1666 | ||
1667 | hi &= (1 << HASHBITS) - 1; | |
1668 | hi %= MAX_HASH_TABLE; | |
1669 | return hi; | |
1670 | } | |
1671 | else if (code == PLUS_EXPR || code == MINUS_EXPR) | |
1672 | return const_hash (TREE_OPERAND (exp, 0)) * 9 | |
1673 | + const_hash (TREE_OPERAND (exp, 1)); | |
1674 | else if (code == NOP_EXPR || code == CONVERT_EXPR) | |
1675 | return const_hash (TREE_OPERAND (exp, 0)) * 7 + 2; | |
1676 | ||
1677 | /* Compute hashing function */ | |
1678 | hi = len; | |
1679 | for (i = 0; i < len; i++) | |
1680 | hi = ((hi * 613) + (unsigned)(p[i])); | |
1681 | ||
1682 | hi &= (1 << HASHBITS) - 1; | |
1683 | hi %= MAX_HASH_TABLE; | |
1684 | return hi; | |
1685 | } | |
1686 | \f | |
1687 | /* Compare a constant expression EXP with a constant-descriptor DESC. | |
1688 | Return 1 if DESC describes a constant with the same value as EXP. */ | |
1689 | ||
1690 | static int | |
1691 | compare_constant (exp, desc) | |
1692 | tree exp; | |
1693 | struct constant_descriptor *desc; | |
1694 | { | |
1695 | return 0 != compare_constant_1 (exp, desc->contents); | |
1696 | } | |
1697 | ||
1698 | /* Compare constant expression EXP with a substring P of a constant descriptor. | |
1699 | If they match, return a pointer to the end of the substring matched. | |
1700 | If they do not match, return 0. | |
1701 | ||
1702 | Since descriptors are written in polish prefix notation, | |
1703 | this function can be used recursively to test one operand of EXP | |
1704 | against a subdescriptor, and if it succeeds it returns the | |
1705 | address of the subdescriptor for the next operand. */ | |
1706 | ||
1707 | static char * | |
1708 | compare_constant_1 (exp, p) | |
1709 | tree exp; | |
1710 | char *p; | |
1711 | { | |
1712 | register char *strp; | |
1713 | register int len; | |
1714 | register enum tree_code code = TREE_CODE (exp); | |
1715 | ||
1716 | if (code != (enum tree_code) *p++) | |
1717 | return 0; | |
1718 | ||
1719 | if (code == INTEGER_CST) | |
1720 | { | |
1721 | /* Integer constants are the same only if the same width of type. */ | |
1722 | if (*p++ != TYPE_PRECISION (TREE_TYPE (exp))) | |
1723 | return 0; | |
1724 | strp = (char *) &TREE_INT_CST_LOW (exp); | |
1725 | len = 2 * sizeof TREE_INT_CST_LOW (exp); | |
1726 | } | |
1727 | else if (code == REAL_CST) | |
1728 | { | |
1729 | /* Real constants are the same only if the same width of type. */ | |
1730 | if (*p++ != TYPE_PRECISION (TREE_TYPE (exp))) | |
1731 | return 0; | |
1732 | strp = (char *) &TREE_REAL_CST (exp); | |
1733 | len = sizeof TREE_REAL_CST (exp); | |
1734 | } | |
1735 | else if (code == STRING_CST) | |
1736 | { | |
1737 | if (flag_writable_strings) | |
1738 | return 0; | |
1739 | strp = TREE_STRING_POINTER (exp); | |
1740 | len = TREE_STRING_LENGTH (exp); | |
1741 | if (bcmp (&TREE_STRING_LENGTH (exp), p, | |
1742 | sizeof TREE_STRING_LENGTH (exp))) | |
1743 | return 0; | |
1744 | p += sizeof TREE_STRING_LENGTH (exp); | |
1745 | } | |
1746 | else if (code == COMPLEX_CST) | |
1747 | { | |
1748 | p = compare_constant_1 (TREE_REALPART (exp), p); | |
1749 | if (p == 0) return 0; | |
1750 | p = compare_constant_1 (TREE_IMAGPART (exp), p); | |
1751 | return p; | |
1752 | } | |
1753 | else if (code == CONSTRUCTOR) | |
1754 | { | |
1755 | register tree link; | |
1756 | int length = list_length (CONSTRUCTOR_ELTS (exp)); | |
1757 | tree type; | |
1758 | ||
1759 | if (bcmp (&length, p, sizeof length)) | |
1760 | return 0; | |
1761 | p += sizeof length; | |
1762 | ||
1763 | /* For record constructors, insist that the types match. | |
1764 | For arrays, just verify both constructors are for arrays. */ | |
1765 | if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) | |
1766 | type = TREE_TYPE (exp); | |
1767 | else | |
1768 | type = 0; | |
1769 | if (bcmp (&type, p, sizeof type)) | |
1770 | return 0; | |
1771 | p += sizeof type; | |
1772 | ||
1773 | /* For arrays, insist that the size in bytes match. */ | |
1774 | if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) | |
1775 | { | |
1776 | int size = int_size_in_bytes (TREE_TYPE (exp)); | |
1777 | if (bcmp (&size, p, sizeof size)) | |
1778 | return 0; | |
1779 | p += sizeof size; | |
1780 | } | |
1781 | ||
1782 | for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) | |
1783 | { | |
1784 | if (TREE_VALUE (link)) | |
1785 | { | |
1786 | if ((p = compare_constant_1 (TREE_VALUE (link), p)) == 0) | |
1787 | return 0; | |
1788 | } | |
1789 | else | |
1790 | { | |
1791 | tree zero = 0; | |
1792 | ||
1793 | if (bcmp (&zero, p, sizeof zero)) | |
1794 | return 0; | |
1795 | p += sizeof zero; | |
1796 | } | |
1797 | } | |
1798 | ||
1799 | return p; | |
1800 | } | |
1801 | else if (code == ADDR_EXPR) | |
1802 | { | |
1803 | struct addr_const value; | |
1804 | decode_addr_const (exp, &value); | |
1805 | strp = (char *) &value.offset; | |
1806 | len = sizeof value.offset; | |
1807 | /* Compare the offset. */ | |
1808 | while (--len >= 0) | |
1809 | if (*p++ != *strp++) | |
1810 | return 0; | |
1811 | /* Compare symbol name. */ | |
1812 | strp = XSTR (value.base, 0); | |
1813 | len = strlen (strp) + 1; | |
1814 | } | |
1815 | else if (code == PLUS_EXPR || code == MINUS_EXPR) | |
1816 | { | |
1817 | p = compare_constant_1 (TREE_OPERAND (exp, 0), p); | |
1818 | if (p == 0) return 0; | |
1819 | p = compare_constant_1 (TREE_OPERAND (exp, 1), p); | |
1820 | return p; | |
1821 | } | |
1822 | else if (code == NOP_EXPR || code == CONVERT_EXPR) | |
1823 | { | |
1824 | p = compare_constant_1 (TREE_OPERAND (exp, 0), p); | |
1825 | return p; | |
1826 | } | |
1827 | ||
1828 | /* Compare constant contents. */ | |
1829 | while (--len >= 0) | |
1830 | if (*p++ != *strp++) | |
1831 | return 0; | |
1832 | ||
1833 | return p; | |
1834 | } | |
1835 | \f | |
1836 | /* Construct a constant descriptor for the expression EXP. | |
1837 | It is up to the caller to enter the descriptor in the hash table. */ | |
1838 | ||
1839 | static struct constant_descriptor * | |
1840 | record_constant (exp) | |
1841 | tree exp; | |
1842 | { | |
1843 | struct constant_descriptor *next = 0; | |
1844 | char *label = 0; | |
1845 | ||
1846 | /* Make a struct constant_descriptor. The first two pointers will | |
1847 | be filled in later. Here we just leave space for them. */ | |
1848 | ||
1849 | obstack_grow (&permanent_obstack, (char *) &next, sizeof next); | |
1850 | obstack_grow (&permanent_obstack, (char *) &label, sizeof label); | |
1851 | record_constant_1 (exp); | |
1852 | return (struct constant_descriptor *) obstack_finish (&permanent_obstack); | |
1853 | } | |
1854 | ||
1855 | /* Add a description of constant expression EXP | |
1856 | to the object growing in `permanent_obstack'. | |
1857 | No need to return its address; the caller will get that | |
1858 | from the obstack when the object is complete. */ | |
1859 | ||
1860 | static void | |
1861 | record_constant_1 (exp) | |
1862 | tree exp; | |
1863 | { | |
1864 | register char *strp; | |
1865 | register int len; | |
1866 | register enum tree_code code = TREE_CODE (exp); | |
1867 | ||
1868 | obstack_1grow (&permanent_obstack, (unsigned int) code); | |
1869 | ||
1870 | if (code == INTEGER_CST) | |
1871 | { | |
1872 | obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp))); | |
1873 | strp = (char *) &TREE_INT_CST_LOW (exp); | |
1874 | len = 2 * sizeof TREE_INT_CST_LOW (exp); | |
1875 | } | |
1876 | else if (code == REAL_CST) | |
1877 | { | |
1878 | obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp))); | |
1879 | strp = (char *) &TREE_REAL_CST (exp); | |
1880 | len = sizeof TREE_REAL_CST (exp); | |
1881 | } | |
1882 | else if (code == STRING_CST) | |
1883 | { | |
1884 | if (flag_writable_strings) | |
1885 | return; | |
1886 | strp = TREE_STRING_POINTER (exp); | |
1887 | len = TREE_STRING_LENGTH (exp); | |
1888 | obstack_grow (&permanent_obstack, (char *) &TREE_STRING_LENGTH (exp), | |
1889 | sizeof TREE_STRING_LENGTH (exp)); | |
1890 | } | |
1891 | else if (code == COMPLEX_CST) | |
1892 | { | |
1893 | record_constant_1 (TREE_REALPART (exp)); | |
1894 | record_constant_1 (TREE_IMAGPART (exp)); | |
1895 | return; | |
1896 | } | |
1897 | else if (code == CONSTRUCTOR) | |
1898 | { | |
1899 | register tree link; | |
1900 | int length = list_length (CONSTRUCTOR_ELTS (exp)); | |
1901 | tree type; | |
1902 | ||
1903 | obstack_grow (&permanent_obstack, (char *) &length, sizeof length); | |
1904 | ||
1905 | /* For record constructors, insist that the types match. | |
1906 | For arrays, just verify both constructors are for arrays. */ | |
1907 | if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) | |
1908 | type = TREE_TYPE (exp); | |
1909 | else | |
1910 | type = 0; | |
1911 | obstack_grow (&permanent_obstack, (char *) &type, sizeof type); | |
1912 | ||
1913 | /* For arrays, insist that the size in bytes match. */ | |
1914 | if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) | |
1915 | { | |
1916 | int size = int_size_in_bytes (TREE_TYPE (exp)); | |
1917 | obstack_grow (&permanent_obstack, (char *) &size, sizeof size); | |
1918 | } | |
1919 | ||
1920 | for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) | |
1921 | { | |
1922 | if (TREE_VALUE (link)) | |
1923 | record_constant_1 (TREE_VALUE (link)); | |
1924 | else | |
1925 | { | |
1926 | tree zero = 0; | |
1927 | ||
1928 | obstack_grow (&permanent_obstack, (char *) &zero, sizeof zero); | |
1929 | } | |
1930 | } | |
1931 | ||
1932 | return; | |
1933 | } | |
1934 | else if (code == ADDR_EXPR) | |
1935 | { | |
1936 | struct addr_const value; | |
1937 | decode_addr_const (exp, &value); | |
1938 | /* Record the offset. */ | |
1939 | obstack_grow (&permanent_obstack, | |
1940 | (char *) &value.offset, sizeof value.offset); | |
1941 | /* Record the symbol name. */ | |
1942 | obstack_grow (&permanent_obstack, XSTR (value.base, 0), | |
1943 | strlen (XSTR (value.base, 0)) + 1); | |
1944 | return; | |
1945 | } | |
1946 | else if (code == PLUS_EXPR || code == MINUS_EXPR) | |
1947 | { | |
1948 | record_constant_1 (TREE_OPERAND (exp, 0)); | |
1949 | record_constant_1 (TREE_OPERAND (exp, 1)); | |
1950 | return; | |
1951 | } | |
1952 | else if (code == NOP_EXPR || code == CONVERT_EXPR) | |
1953 | { | |
1954 | record_constant_1 (TREE_OPERAND (exp, 0)); | |
1955 | return; | |
1956 | } | |
1957 | ||
1958 | /* Record constant contents. */ | |
1959 | obstack_grow (&permanent_obstack, strp, len); | |
1960 | } | |
1961 | \f | |
1962 | /* Return an rtx representing a reference to constant data in memory | |
1963 | for the constant expression EXP. | |
1964 | If assembler code for such a constant has already been output, | |
1965 | return an rtx to refer to it. | |
1966 | Otherwise, output such a constant in memory and generate | |
1967 | an rtx for it. The TREE_CST_RTL of EXP is set up to point to that rtx. | |
1968 | The const_hash_table records which constants already have label strings. */ | |
1969 | ||
1970 | rtx | |
1971 | output_constant_def (exp) | |
1972 | tree exp; | |
1973 | { | |
1974 | register int hash, align; | |
1975 | register struct constant_descriptor *desc; | |
1976 | char label[256]; | |
1977 | char *found = 0; | |
1978 | int reloc; | |
1979 | register rtx def; | |
1980 | ||
1981 | if (TREE_CODE (exp) == INTEGER_CST) | |
1982 | abort (); /* No TREE_CST_RTL slot in these. */ | |
1983 | ||
1984 | if (TREE_CST_RTL (exp)) | |
1985 | return TREE_CST_RTL (exp); | |
1986 | ||
1987 | /* Make sure any other constants whose addresses appear in EXP | |
1988 | are assigned label numbers. */ | |
1989 | ||
1990 | reloc = output_addressed_constants (exp); | |
1991 | ||
1992 | /* Compute hash code of EXP. Search the descriptors for that hash code | |
1993 | to see if any of them describes EXP. If yes, the descriptor records | |
1994 | the label number already assigned. */ | |
1995 | ||
1996 | hash = const_hash (exp) % MAX_HASH_TABLE; | |
1997 | ||
1998 | for (desc = const_hash_table[hash]; desc; desc = desc->next) | |
1999 | if (compare_constant (exp, desc)) | |
2000 | { | |
2001 | found = desc->label; | |
2002 | break; | |
2003 | } | |
2004 | ||
2005 | if (found == 0) | |
2006 | { | |
2007 | /* No constant equal to EXP is known to have been output. | |
2008 | Make a constant descriptor to enter EXP in the hash table. | |
2009 | Assign the label number and record it in the descriptor for | |
2010 | future calls to this function to find. */ | |
2011 | ||
2012 | /* Create a string containing the label name, in LABEL. */ | |
2013 | ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno); | |
2014 | ||
2015 | desc = record_constant (exp); | |
2016 | desc->next = const_hash_table[hash]; | |
2017 | desc->label | |
2018 | = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label)); | |
2019 | const_hash_table[hash] = desc; | |
2020 | } | |
2021 | ||
2022 | /* We have a symbol name; construct the SYMBOL_REF and the MEM. */ | |
2023 | ||
2024 | push_obstacks_nochange (); | |
2025 | if (TREE_PERMANENT (exp)) | |
2026 | end_temporary_allocation (); | |
2027 | ||
2028 | def = gen_rtx (SYMBOL_REF, Pmode, desc->label); | |
2029 | ||
2030 | TREE_CST_RTL (exp) | |
2031 | = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)), def); | |
2032 | RTX_UNCHANGING_P (TREE_CST_RTL (exp)) = 1; | |
2033 | if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE | |
2034 | || TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) | |
2035 | MEM_IN_STRUCT_P (TREE_CST_RTL (exp)) = 1; | |
2036 | ||
2037 | pop_obstacks (); | |
2038 | ||
2039 | /* Optionally set flags or add text to the name to record information | |
2040 | such as that it is a function name. If the name is changed, the macro | |
2041 | ASM_OUTPUT_LABELREF will have to know how to strip this information. | |
2042 | And if it finds a * at the beginning after doing so, it must handle | |
2043 | that too. */ | |
2044 | #ifdef ENCODE_SECTION_INFO | |
2045 | ENCODE_SECTION_INFO (exp); | |
2046 | #endif | |
2047 | ||
2048 | if (found == 0) | |
2049 | { | |
2050 | /* Now output assembler code to define that label | |
2051 | and follow it with the data of EXP. */ | |
2052 | ||
2053 | /* First switch to text section, except for writable strings. */ | |
2054 | #ifdef SELECT_SECTION | |
2055 | SELECT_SECTION (exp, reloc); | |
2056 | #else | |
2057 | if (((TREE_CODE (exp) == STRING_CST) && flag_writable_strings) | |
2058 | || (flag_pic && reloc)) | |
2059 | data_section (); | |
2060 | else | |
2061 | readonly_data_section (); | |
2062 | #endif | |
2063 | ||
2064 | /* Align the location counter as required by EXP's data type. */ | |
2065 | align = TYPE_ALIGN (TREE_TYPE (exp)); | |
2066 | #ifdef CONSTANT_ALIGNMENT | |
2067 | align = CONSTANT_ALIGNMENT (exp, align); | |
2068 | #endif | |
2069 | ||
2070 | if (align > BITS_PER_UNIT) | |
2071 | ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT)); | |
2072 | ||
2073 | /* Output the label itself. */ | |
2074 | ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", const_labelno); | |
2075 | ||
2076 | /* Output the value of EXP. */ | |
2077 | output_constant (exp, | |
2078 | (TREE_CODE (exp) == STRING_CST | |
2079 | ? TREE_STRING_LENGTH (exp) | |
2080 | : int_size_in_bytes (TREE_TYPE (exp)))); | |
2081 | ||
2082 | ++const_labelno; | |
2083 | } | |
2084 | ||
2085 | return TREE_CST_RTL (exp); | |
2086 | } | |
2087 | \f | |
2088 | /* Similar hash facility for making memory-constants | |
2089 | from constant rtl-expressions. It is used on RISC machines | |
2090 | where immediate integer arguments and constant addresses are restricted | |
2091 | so that such constants must be stored in memory. | |
2092 | ||
2093 | This pool of constants is reinitialized for each function | |
2094 | so each function gets its own constants-pool that comes right before it. | |
2095 | ||
2096 | All structures allocated here are discarded when functions are saved for | |
2097 | inlining, so they do not need to be allocated permanently. */ | |
2098 | ||
2099 | #define MAX_RTX_HASH_TABLE 61 | |
2100 | static struct constant_descriptor **const_rtx_hash_table; | |
2101 | ||
2102 | /* Structure to represent sufficient information about a constant so that | |
2103 | it can be output when the constant pool is output, so that function | |
2104 | integration can be done, and to simplify handling on machines that reference | |
2105 | constant pool as base+displacement. */ | |
2106 | ||
2107 | struct pool_constant | |
2108 | { | |
2109 | struct constant_descriptor *desc; | |
2110 | struct pool_constant *next; | |
2111 | enum machine_mode mode; | |
2112 | rtx constant; | |
2113 | int labelno; | |
2114 | int align; | |
2115 | int offset; | |
2116 | }; | |
2117 | ||
2118 | /* Pointers to first and last constant in pool. */ | |
2119 | ||
2120 | static struct pool_constant *first_pool, *last_pool; | |
2121 | ||
2122 | /* Current offset in constant pool (does not include any machine-specific | |
2123 | header. */ | |
2124 | ||
2125 | static int pool_offset; | |
2126 | ||
2127 | /* Structure used to maintain hash table mapping symbols used to their | |
2128 | corresponding constants. */ | |
2129 | ||
2130 | struct pool_sym | |
2131 | { | |
2132 | char *label; | |
2133 | struct pool_constant *pool; | |
2134 | struct pool_sym *next; | |
2135 | }; | |
2136 | ||
2137 | static struct pool_sym **const_rtx_sym_hash_table; | |
2138 | ||
2139 | /* Hash code for a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true. | |
2140 | The argument is XSTR (... , 0) */ | |
2141 | ||
2142 | #define SYMHASH(LABEL) \ | |
2143 | ((((HOST_WIDE_INT) (LABEL)) & ((1 << HASHBITS) - 1)) % MAX_RTX_HASH_TABLE) | |
2144 | \f | |
2145 | /* Initialize constant pool hashing for next function. */ | |
2146 | ||
2147 | void | |
2148 | init_const_rtx_hash_table () | |
2149 | { | |
2150 | const_rtx_hash_table | |
2151 | = ((struct constant_descriptor **) | |
2152 | oballoc (MAX_RTX_HASH_TABLE * sizeof (struct constant_descriptor *))); | |
2153 | const_rtx_sym_hash_table | |
2154 | = ((struct pool_sym **) | |
2155 | oballoc (MAX_RTX_HASH_TABLE * sizeof (struct pool_sym *))); | |
2156 | bzero (const_rtx_hash_table, | |
2157 | MAX_RTX_HASH_TABLE * sizeof (struct constant_descriptor *)); | |
2158 | bzero (const_rtx_sym_hash_table, | |
2159 | MAX_RTX_HASH_TABLE * sizeof (struct pool_sym *)); | |
2160 | ||
2161 | first_pool = last_pool = 0; | |
2162 | pool_offset = 0; | |
2163 | } | |
2164 | ||
2165 | /* Save and restore it for a nested function. */ | |
2166 | ||
2167 | void | |
2168 | save_varasm_status (p) | |
2169 | struct function *p; | |
2170 | { | |
2171 | p->const_rtx_hash_table = const_rtx_hash_table; | |
2172 | p->const_rtx_sym_hash_table = const_rtx_sym_hash_table; | |
2173 | p->first_pool = first_pool; | |
2174 | p->last_pool = last_pool; | |
2175 | p->pool_offset = pool_offset; | |
2176 | } | |
2177 | ||
2178 | void | |
2179 | restore_varasm_status (p) | |
2180 | struct function *p; | |
2181 | { | |
2182 | const_rtx_hash_table = p->const_rtx_hash_table; | |
2183 | const_rtx_sym_hash_table = p->const_rtx_sym_hash_table; | |
2184 | first_pool = p->first_pool; | |
2185 | last_pool = p->last_pool; | |
2186 | pool_offset = p->pool_offset; | |
2187 | } | |
2188 | \f | |
2189 | enum kind { RTX_DOUBLE, RTX_INT }; | |
2190 | ||
2191 | struct rtx_const | |
2192 | { | |
2193 | #ifdef ONLY_INT_FIELDS | |
2194 | unsigned int kind : 16; | |
2195 | unsigned int mode : 16; | |
2196 | #else | |
2197 | enum kind kind : 16; | |
2198 | enum machine_mode mode : 16; | |
2199 | #endif | |
2200 | union { | |
2201 | union real_extract du; | |
2202 | struct addr_const addr; | |
2203 | } un; | |
2204 | }; | |
2205 | ||
2206 | /* Express an rtx for a constant integer (perhaps symbolic) | |
2207 | as the sum of a symbol or label plus an explicit integer. | |
2208 | They are stored into VALUE. */ | |
2209 | ||
2210 | static void | |
2211 | decode_rtx_const (mode, x, value) | |
2212 | enum machine_mode mode; | |
2213 | rtx x; | |
2214 | struct rtx_const *value; | |
2215 | { | |
2216 | /* Clear the whole structure, including any gaps. */ | |
2217 | ||
2218 | { | |
2219 | int *p = (int *) value; | |
2220 | int *end = (int *) (value + 1); | |
2221 | while (p < end) | |
2222 | *p++ = 0; | |
2223 | } | |
2224 | ||
2225 | value->kind = RTX_INT; /* Most usual kind. */ | |
2226 | value->mode = mode; | |
2227 | ||
2228 | switch (GET_CODE (x)) | |
2229 | { | |
2230 | case CONST_DOUBLE: | |
2231 | value->kind = RTX_DOUBLE; | |
2232 | value->mode = GET_MODE (x); | |
2233 | bcopy (&CONST_DOUBLE_LOW (x), &value->un.du, sizeof value->un.du); | |
2234 | break; | |
2235 | ||
2236 | case CONST_INT: | |
2237 | value->un.addr.offset = INTVAL (x); | |
2238 | break; | |
2239 | ||
2240 | case SYMBOL_REF: | |
2241 | case LABEL_REF: | |
2242 | case PC: | |
2243 | value->un.addr.base = x; | |
2244 | break; | |
2245 | ||
2246 | case CONST: | |
2247 | x = XEXP (x, 0); | |
2248 | if (GET_CODE (x) == PLUS) | |
2249 | { | |
2250 | value->un.addr.base = XEXP (x, 0); | |
2251 | if (GET_CODE (XEXP (x, 1)) != CONST_INT) | |
2252 | abort (); | |
2253 | value->un.addr.offset = INTVAL (XEXP (x, 1)); | |
2254 | } | |
2255 | else if (GET_CODE (x) == MINUS) | |
2256 | { | |
2257 | value->un.addr.base = XEXP (x, 0); | |
2258 | if (GET_CODE (XEXP (x, 1)) != CONST_INT) | |
2259 | abort (); | |
2260 | value->un.addr.offset = - INTVAL (XEXP (x, 1)); | |
2261 | } | |
2262 | else | |
2263 | abort (); | |
2264 | break; | |
2265 | ||
2266 | default: | |
2267 | abort (); | |
2268 | } | |
2269 | ||
2270 | if (value->kind == RTX_INT && value->un.addr.base != 0) | |
2271 | switch (GET_CODE (value->un.addr.base)) | |
2272 | { | |
2273 | case SYMBOL_REF: | |
2274 | case LABEL_REF: | |
2275 | /* Use the string's address, not the SYMBOL_REF's address, | |
2276 | for the sake of addresses of library routines. | |
2277 | For a LABEL_REF, compare labels. */ | |
2278 | value->un.addr.base = XEXP (value->un.addr.base, 0); | |
2279 | } | |
2280 | } | |
2281 | ||
2282 | /* Given a MINUS expression, simplify it if both sides | |
2283 | include the same symbol. */ | |
2284 | ||
2285 | rtx | |
2286 | simplify_subtraction (x) | |
2287 | rtx x; | |
2288 | { | |
2289 | struct rtx_const val0, val1; | |
2290 | ||
2291 | decode_rtx_const (GET_MODE (x), XEXP (x, 0), &val0); | |
2292 | decode_rtx_const (GET_MODE (x), XEXP (x, 1), &val1); | |
2293 | ||
2294 | if (val0.un.addr.base == val1.un.addr.base) | |
2295 | return GEN_INT (val0.un.addr.offset - val1.un.addr.offset); | |
2296 | return x; | |
2297 | } | |
2298 | ||
2299 | /* Compute a hash code for a constant RTL expression. */ | |
2300 | ||
2301 | int | |
2302 | const_hash_rtx (mode, x) | |
2303 | enum machine_mode mode; | |
2304 | rtx x; | |
2305 | { | |
2306 | register int hi, i; | |
2307 | ||
2308 | struct rtx_const value; | |
2309 | decode_rtx_const (mode, x, &value); | |
2310 | ||
2311 | /* Compute hashing function */ | |
2312 | hi = 0; | |
2313 | for (i = 0; i < sizeof value / sizeof (int); i++) | |
2314 | hi += ((int *) &value)[i]; | |
2315 | ||
2316 | hi &= (1 << HASHBITS) - 1; | |
2317 | hi %= MAX_RTX_HASH_TABLE; | |
2318 | return hi; | |
2319 | } | |
2320 | ||
2321 | /* Compare a constant rtl object X with a constant-descriptor DESC. | |
2322 | Return 1 if DESC describes a constant with the same value as X. */ | |
2323 | ||
2324 | static int | |
2325 | compare_constant_rtx (mode, x, desc) | |
2326 | enum machine_mode mode; | |
2327 | rtx x; | |
2328 | struct constant_descriptor *desc; | |
2329 | { | |
2330 | register int *p = (int *) desc->contents; | |
2331 | register int *strp; | |
2332 | register int len; | |
2333 | struct rtx_const value; | |
2334 | ||
2335 | decode_rtx_const (mode, x, &value); | |
2336 | strp = (int *) &value; | |
2337 | len = sizeof value / sizeof (int); | |
2338 | ||
2339 | /* Compare constant contents. */ | |
2340 | while (--len >= 0) | |
2341 | if (*p++ != *strp++) | |
2342 | return 0; | |
2343 | ||
2344 | return 1; | |
2345 | } | |
2346 | ||
2347 | /* Construct a constant descriptor for the rtl-expression X. | |
2348 | It is up to the caller to enter the descriptor in the hash table. */ | |
2349 | ||
2350 | static struct constant_descriptor * | |
2351 | record_constant_rtx (mode, x) | |
2352 | enum machine_mode mode; | |
2353 | rtx x; | |
2354 | { | |
2355 | struct constant_descriptor *ptr; | |
2356 | char *label; | |
2357 | struct rtx_const value; | |
2358 | ||
2359 | decode_rtx_const (mode, x, &value); | |
2360 | ||
2361 | obstack_grow (current_obstack, &ptr, sizeof ptr); | |
2362 | obstack_grow (current_obstack, &label, sizeof label); | |
2363 | ||
2364 | /* Record constant contents. */ | |
2365 | obstack_grow (current_obstack, &value, sizeof value); | |
2366 | ||
2367 | return (struct constant_descriptor *) obstack_finish (current_obstack); | |
2368 | } | |
2369 | \f | |
2370 | /* Given a constant rtx X, make (or find) a memory constant for its value | |
2371 | and return a MEM rtx to refer to it in memory. */ | |
2372 | ||
2373 | rtx | |
2374 | force_const_mem (mode, x) | |
2375 | enum machine_mode mode; | |
2376 | rtx x; | |
2377 | { | |
2378 | register int hash; | |
2379 | register struct constant_descriptor *desc; | |
2380 | char label[256]; | |
2381 | char *found = 0; | |
2382 | rtx def; | |
2383 | ||
2384 | /* If we want this CONST_DOUBLE in the same mode as it is in memory | |
2385 | (this will always be true for floating CONST_DOUBLEs that have been | |
2386 | placed in memory, but not for VOIDmode (integer) CONST_DOUBLEs), | |
2387 | use the previous copy. Otherwise, make a new one. Note that in | |
2388 | the unlikely event that this same CONST_DOUBLE is used in two different | |
2389 | modes in an alternating fashion, we will allocate a lot of different | |
2390 | memory locations, but this should be extremely rare. */ | |
2391 | ||
2392 | /* Don't use CONST_DOUBLE_MEM in a nested function. | |
2393 | Nested functions have their own constant pools, | |
2394 | so they can't share the same values in CONST_DOUBLE_MEM | |
2395 | with the containing function. */ | |
2396 | if (outer_function_chain == 0) | |
2397 | if (GET_CODE (x) == CONST_DOUBLE | |
2398 | && GET_CODE (CONST_DOUBLE_MEM (x)) == MEM | |
2399 | && GET_MODE (CONST_DOUBLE_MEM (x)) == mode) | |
2400 | return CONST_DOUBLE_MEM (x); | |
2401 | ||
2402 | /* Compute hash code of X. Search the descriptors for that hash code | |
2403 | to see if any of them describes X. If yes, the descriptor records | |
2404 | the label number already assigned. */ | |
2405 | ||
2406 | hash = const_hash_rtx (mode, x); | |
2407 | ||
2408 | for (desc = const_rtx_hash_table[hash]; desc; desc = desc->next) | |
2409 | if (compare_constant_rtx (mode, x, desc)) | |
2410 | { | |
2411 | found = desc->label; | |
2412 | break; | |
2413 | } | |
2414 | ||
2415 | if (found == 0) | |
2416 | { | |
2417 | register struct pool_constant *pool; | |
2418 | register struct pool_sym *sym; | |
2419 | int align; | |
2420 | ||
2421 | /* No constant equal to X is known to have been output. | |
2422 | Make a constant descriptor to enter X in the hash table. | |
2423 | Assign the label number and record it in the descriptor for | |
2424 | future calls to this function to find. */ | |
2425 | ||
2426 | desc = record_constant_rtx (mode, x); | |
2427 | desc->next = const_rtx_hash_table[hash]; | |
2428 | const_rtx_hash_table[hash] = desc; | |
2429 | ||
2430 | /* Align the location counter as required by EXP's data type. */ | |
2431 | align = (mode == VOIDmode) ? UNITS_PER_WORD : GET_MODE_SIZE (mode); | |
2432 | if (align > BIGGEST_ALIGNMENT / BITS_PER_UNIT) | |
2433 | align = BIGGEST_ALIGNMENT / BITS_PER_UNIT; | |
2434 | ||
2435 | pool_offset += align - 1; | |
2436 | pool_offset &= ~ (align - 1); | |
2437 | ||
2438 | /* Allocate a pool constant descriptor, fill it in, and chain it in. */ | |
2439 | ||
2440 | pool = (struct pool_constant *) oballoc (sizeof (struct pool_constant)); | |
2441 | pool->desc = desc; | |
2442 | pool->constant = x; | |
2443 | pool->mode = mode; | |
2444 | pool->labelno = const_labelno; | |
2445 | pool->align = align; | |
2446 | pool->offset = pool_offset; | |
2447 | pool->next = 0; | |
2448 | ||
2449 | if (last_pool == 0) | |
2450 | first_pool = pool; | |
2451 | else | |
2452 | last_pool->next = pool; | |
2453 | ||
2454 | last_pool = pool; | |
2455 | pool_offset += GET_MODE_SIZE (mode); | |
2456 | ||
2457 | /* Create a string containing the label name, in LABEL. */ | |
2458 | ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno); | |
2459 | ||
2460 | ++const_labelno; | |
2461 | ||
2462 | desc->label = found | |
2463 | = (char *) obstack_copy0 (saveable_obstack, label, strlen (label)); | |
2464 | ||
2465 | /* Add label to symbol hash table. */ | |
2466 | hash = SYMHASH (found); | |
2467 | sym = (struct pool_sym *) oballoc (sizeof (struct pool_sym)); | |
2468 | sym->label = found; | |
2469 | sym->pool = pool; | |
2470 | sym->next = const_rtx_sym_hash_table[hash]; | |
2471 | const_rtx_sym_hash_table[hash] = sym; | |
2472 | } | |
2473 | ||
2474 | /* We have a symbol name; construct the SYMBOL_REF and the MEM. */ | |
2475 | ||
2476 | def = gen_rtx (MEM, mode, gen_rtx (SYMBOL_REF, Pmode, found)); | |
2477 | ||
2478 | RTX_UNCHANGING_P (def) = 1; | |
2479 | /* Mark the symbol_ref as belonging to this constants pool. */ | |
2480 | CONSTANT_POOL_ADDRESS_P (XEXP (def, 0)) = 1; | |
2481 | current_function_uses_const_pool = 1; | |
2482 | ||
2483 | if (outer_function_chain == 0) | |
2484 | if (GET_CODE (x) == CONST_DOUBLE) | |
2485 | { | |
2486 | if (CONST_DOUBLE_MEM (x) == cc0_rtx) | |
2487 | { | |
2488 | CONST_DOUBLE_CHAIN (x) = const_double_chain; | |
2489 | const_double_chain = x; | |
2490 | } | |
2491 | CONST_DOUBLE_MEM (x) = def; | |
2492 | } | |
2493 | ||
2494 | return def; | |
2495 | } | |
2496 | \f | |
2497 | /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to | |
2498 | the corresponding pool_constant structure. */ | |
2499 | ||
2500 | static struct pool_constant * | |
2501 | find_pool_constant (addr) | |
2502 | rtx addr; | |
2503 | { | |
2504 | struct pool_sym *sym; | |
2505 | char *label = XSTR (addr, 0); | |
2506 | ||
2507 | for (sym = const_rtx_sym_hash_table[SYMHASH (label)]; sym; sym = sym->next) | |
2508 | if (sym->label == label) | |
2509 | return sym->pool; | |
2510 | ||
2511 | abort (); | |
2512 | } | |
2513 | ||
2514 | /* Given a constant pool SYMBOL_REF, return the corresponding constant. */ | |
2515 | ||
2516 | rtx | |
2517 | get_pool_constant (addr) | |
2518 | rtx addr; | |
2519 | { | |
2520 | return (find_pool_constant (addr))->constant; | |
2521 | } | |
2522 | ||
2523 | /* Similar, return the mode. */ | |
2524 | ||
2525 | enum machine_mode | |
2526 | get_pool_mode (addr) | |
2527 | rtx addr; | |
2528 | { | |
2529 | return (find_pool_constant (addr))->mode; | |
2530 | } | |
2531 | ||
2532 | /* Similar, return the offset in the constant pool. */ | |
2533 | ||
2534 | int | |
2535 | get_pool_offset (addr) | |
2536 | rtx addr; | |
2537 | { | |
2538 | return (find_pool_constant (addr))->offset; | |
2539 | } | |
2540 | ||
2541 | /* Return the size of the constant pool. */ | |
2542 | ||
2543 | int | |
2544 | get_pool_size () | |
2545 | { | |
2546 | return pool_offset; | |
2547 | } | |
2548 | \f | |
2549 | /* Write all the constants in the constant pool. */ | |
2550 | ||
2551 | void | |
2552 | output_constant_pool (fnname, fndecl) | |
2553 | char *fnname; | |
2554 | tree fndecl; | |
2555 | { | |
2556 | struct pool_constant *pool; | |
2557 | rtx x; | |
2558 | union real_extract u; | |
2559 | ||
2560 | #ifdef ASM_OUTPUT_POOL_PROLOGUE | |
2561 | ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool_offset); | |
2562 | #endif | |
2563 | ||
2564 | for (pool = first_pool; pool; pool = pool->next) | |
2565 | { | |
2566 | x = pool->constant; | |
2567 | ||
2568 | /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF) | |
2569 | whose CODE_LABEL has been deleted. This can occur if a jump table | |
2570 | is eliminated by optimization. If so, write a constant of zero | |
2571 | instead. Note that this can also happen by turning the | |
2572 | CODE_LABEL into a NOTE. */ | |
2573 | if (((GET_CODE (x) == LABEL_REF | |
2574 | && (INSN_DELETED_P (XEXP (x, 0)) | |
2575 | || GET_CODE (XEXP (x, 0)) == NOTE))) | |
2576 | || (GET_CODE (x) == CONST && GET_CODE (XEXP (x, 0)) == PLUS | |
2577 | && GET_CODE (XEXP (XEXP (x, 0), 0)) == LABEL_REF | |
2578 | && (INSN_DELETED_P (XEXP (XEXP (XEXP (x, 0), 0), 0)) | |
2579 | || GET_CODE (XEXP (XEXP (XEXP (x, 0), 0), 0)) == NOTE))) | |
2580 | x = const0_rtx; | |
2581 | ||
2582 | /* First switch to correct section. */ | |
2583 | #ifdef SELECT_RTX_SECTION | |
2584 | SELECT_RTX_SECTION (pool->mode, x); | |
2585 | #else | |
2586 | readonly_data_section (); | |
2587 | #endif | |
2588 | ||
2589 | #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY | |
2590 | ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, pool->mode, | |
2591 | pool->align, pool->labelno, done); | |
2592 | #endif | |
2593 | ||
2594 | if (pool->align > 1) | |
2595 | ASM_OUTPUT_ALIGN (asm_out_file, exact_log2 (pool->align)); | |
2596 | ||
2597 | /* Output the label. */ | |
2598 | ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", pool->labelno); | |
2599 | ||
2600 | /* Output the value of the constant itself. */ | |
2601 | switch (GET_MODE_CLASS (pool->mode)) | |
2602 | { | |
2603 | case MODE_FLOAT: | |
2604 | if (GET_CODE (x) != CONST_DOUBLE) | |
2605 | abort (); | |
2606 | ||
2607 | bcopy (&CONST_DOUBLE_LOW (x), &u, sizeof u); | |
2608 | assemble_real (u.d, pool->mode); | |
2609 | break; | |
2610 | ||
2611 | case MODE_INT: | |
2612 | case MODE_PARTIAL_INT: | |
2613 | assemble_integer (x, GET_MODE_SIZE (pool->mode), 1); | |
2614 | break; | |
2615 | ||
2616 | default: | |
2617 | abort (); | |
2618 | } | |
2619 | ||
2620 | done: ; | |
2621 | } | |
2622 | ||
2623 | /* Done with this pool. */ | |
2624 | first_pool = last_pool = 0; | |
2625 | } | |
2626 | \f | |
2627 | /* Find all the constants whose addresses are referenced inside of EXP, | |
2628 | and make sure assembler code with a label has been output for each one. | |
2629 | Indicate whether an ADDR_EXPR has been encountered. */ | |
2630 | ||
2631 | int | |
2632 | output_addressed_constants (exp) | |
2633 | tree exp; | |
2634 | { | |
2635 | int reloc = 0; | |
2636 | ||
2637 | switch (TREE_CODE (exp)) | |
2638 | { | |
2639 | case ADDR_EXPR: | |
2640 | { | |
2641 | register tree constant = TREE_OPERAND (exp, 0); | |
2642 | ||
2643 | while (TREE_CODE (constant) == COMPONENT_REF) | |
2644 | { | |
2645 | constant = TREE_OPERAND (constant, 0); | |
2646 | } | |
2647 | ||
2648 | if (TREE_CODE_CLASS (TREE_CODE (constant)) == 'c' | |
2649 | || TREE_CODE (constant) == CONSTRUCTOR) | |
2650 | /* No need to do anything here | |
2651 | for addresses of variables or functions. */ | |
2652 | output_constant_def (constant); | |
2653 | } | |
2654 | reloc = 1; | |
2655 | break; | |
2656 | ||
2657 | case PLUS_EXPR: | |
2658 | case MINUS_EXPR: | |
2659 | reloc = output_addressed_constants (TREE_OPERAND (exp, 0)); | |
2660 | reloc |= output_addressed_constants (TREE_OPERAND (exp, 1)); | |
2661 | break; | |
2662 | ||
2663 | case NOP_EXPR: | |
2664 | case CONVERT_EXPR: | |
2665 | case NON_LVALUE_EXPR: | |
2666 | reloc = output_addressed_constants (TREE_OPERAND (exp, 0)); | |
2667 | break; | |
2668 | ||
2669 | case CONSTRUCTOR: | |
2670 | { | |
2671 | register tree link; | |
2672 | for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link)) | |
2673 | if (TREE_VALUE (link) != 0) | |
2674 | reloc |= output_addressed_constants (TREE_VALUE (link)); | |
2675 | } | |
2676 | break; | |
2677 | ||
2678 | case ERROR_MARK: | |
2679 | break; | |
2680 | } | |
2681 | return reloc; | |
2682 | } | |
2683 | \f | |
2684 | /* Output assembler code for constant EXP to FILE, with no label. | |
2685 | This includes the pseudo-op such as ".int" or ".byte", and a newline. | |
2686 | Assumes output_addressed_constants has been done on EXP already. | |
2687 | ||
2688 | Generate exactly SIZE bytes of assembler data, padding at the end | |
2689 | with zeros if necessary. SIZE must always be specified. | |
2690 | ||
2691 | SIZE is important for structure constructors, | |
2692 | since trailing members may have been omitted from the constructor. | |
2693 | It is also important for initialization of arrays from string constants | |
2694 | since the full length of the string constant might not be wanted. | |
2695 | It is also needed for initialization of unions, where the initializer's | |
2696 | type is just one member, and that may not be as long as the union. | |
2697 | ||
2698 | There a case in which we would fail to output exactly SIZE bytes: | |
2699 | for a structure constructor that wants to produce more than SIZE bytes. | |
2700 | But such constructors will never be generated for any possible input. */ | |
2701 | ||
2702 | void | |
2703 | output_constant (exp, size) | |
2704 | register tree exp; | |
2705 | register int size; | |
2706 | { | |
2707 | register enum tree_code code = TREE_CODE (TREE_TYPE (exp)); | |
2708 | rtx x; | |
2709 | ||
2710 | if (size == 0) | |
2711 | return; | |
2712 | ||
2713 | /* Allow a constructor with no elements for any data type. | |
2714 | This means to fill the space with zeros. */ | |
2715 | if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0) | |
2716 | { | |
2717 | assemble_zeros (size); | |
2718 | return; | |
2719 | } | |
2720 | ||
2721 | /* Eliminate the NOP_EXPR that makes a cast not be an lvalue. | |
2722 | That way we get the constant (we hope) inside it. */ | |
2723 | if (TREE_CODE (exp) == NOP_EXPR | |
2724 | && TREE_TYPE (exp) == TREE_TYPE (TREE_OPERAND (exp, 0))) | |
2725 | exp = TREE_OPERAND (exp, 0); | |
2726 | ||
2727 | switch (code) | |
2728 | { | |
2729 | case CHAR_TYPE: | |
2730 | case BOOLEAN_TYPE: | |
2731 | case INTEGER_TYPE: | |
2732 | case ENUMERAL_TYPE: | |
2733 | case POINTER_TYPE: | |
2734 | case REFERENCE_TYPE: | |
2735 | /* ??? What about (int)((float)(int)&foo + 4) */ | |
2736 | while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR | |
2737 | || TREE_CODE (exp) == NON_LVALUE_EXPR) | |
2738 | exp = TREE_OPERAND (exp, 0); | |
2739 | ||
2740 | if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode, | |
2741 | EXPAND_INITIALIZER), | |
2742 | size, 0)) | |
2743 | error ("initializer for integer value is too complicated"); | |
2744 | size = 0; | |
2745 | break; | |
2746 | ||
2747 | case REAL_TYPE: | |
2748 | if (TREE_CODE (exp) != REAL_CST) | |
2749 | error ("initializer for floating value is not a floating constant"); | |
2750 | ||
2751 | assemble_real (TREE_REAL_CST (exp), | |
2752 | mode_for_size (size * BITS_PER_UNIT, MODE_FLOAT, 0)); | |
2753 | size = 0; | |
2754 | break; | |
2755 | ||
2756 | case COMPLEX_TYPE: | |
2757 | output_constant (TREE_REALPART (exp), size / 2); | |
2758 | output_constant (TREE_IMAGPART (exp), size / 2); | |
2759 | size -= (size / 2) * 2; | |
2760 | break; | |
2761 | ||
2762 | case ARRAY_TYPE: | |
2763 | if (TREE_CODE (exp) == CONSTRUCTOR) | |
2764 | { | |
2765 | output_constructor (exp, size); | |
2766 | return; | |
2767 | } | |
2768 | else if (TREE_CODE (exp) == STRING_CST) | |
2769 | { | |
2770 | int excess = 0; | |
2771 | ||
2772 | if (size > TREE_STRING_LENGTH (exp)) | |
2773 | { | |
2774 | excess = size - TREE_STRING_LENGTH (exp); | |
2775 | size = TREE_STRING_LENGTH (exp); | |
2776 | } | |
2777 | ||
2778 | assemble_string (TREE_STRING_POINTER (exp), size); | |
2779 | size = excess; | |
2780 | } | |
2781 | else | |
2782 | abort (); | |
2783 | break; | |
2784 | ||
2785 | case RECORD_TYPE: | |
2786 | case UNION_TYPE: | |
2787 | if (TREE_CODE (exp) == CONSTRUCTOR) | |
2788 | output_constructor (exp, size); | |
2789 | else | |
2790 | abort (); | |
2791 | return; | |
2792 | } | |
2793 | ||
2794 | if (size > 0) | |
2795 | assemble_zeros (size); | |
2796 | } | |
2797 | \f | |
2798 | /* Subroutine of output_constant, used for CONSTRUCTORs | |
2799 | (aggregate constants). | |
2800 | Generate at least SIZE bytes, padding if necessary. */ | |
2801 | ||
2802 | void | |
2803 | output_constructor (exp, size) | |
2804 | tree exp; | |
2805 | int size; | |
2806 | { | |
2807 | register tree link, field = 0; | |
2808 | /* Number of bytes output or skipped so far. | |
2809 | In other words, current position within the constructor. */ | |
2810 | int total_bytes = 0; | |
2811 | /* Non-zero means BYTE contains part of a byte, to be output. */ | |
2812 | int byte_buffer_in_use = 0; | |
2813 | register int byte; | |
2814 | ||
2815 | if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT) | |
2816 | abort (); | |
2817 | ||
2818 | if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE) | |
2819 | field = TYPE_FIELDS (TREE_TYPE (exp)); | |
2820 | ||
2821 | /* As LINK goes through the elements of the constant, | |
2822 | FIELD goes through the structure fields, if the constant is a structure. | |
2823 | if the constant is a union, then we override this, | |
2824 | by getting the field from the TREE_LIST element. | |
2825 | But the constant could also be an array. Then FIELD is zero. */ | |
2826 | for (link = CONSTRUCTOR_ELTS (exp); | |
2827 | link; | |
2828 | link = TREE_CHAIN (link), | |
2829 | field = field ? TREE_CHAIN (field) : 0) | |
2830 | { | |
2831 | tree val = TREE_VALUE (link); | |
2832 | /* the element in a union constructor specifies the proper field. */ | |
2833 | if (TREE_PURPOSE (link) != 0) | |
2834 | field = TREE_PURPOSE (link); | |
2835 | ||
2836 | /* Eliminate the marker that makes a cast not be an lvalue. */ | |
2837 | if (val != 0) | |
2838 | STRIP_NOPS (val); | |
2839 | ||
2840 | if (field == 0 || !DECL_BIT_FIELD (field)) | |
2841 | { | |
2842 | register int fieldsize; | |
2843 | /* Since this structure is static, | |
2844 | we know the positions are constant. */ | |
2845 | int bitpos = (field ? (TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field)) | |
2846 | / BITS_PER_UNIT) | |
2847 | : 0); | |
2848 | ||
2849 | /* An element that is not a bit-field. | |
2850 | Output any buffered-up bit-fields preceding it. */ | |
2851 | if (byte_buffer_in_use) | |
2852 | { | |
2853 | ASM_OUTPUT_BYTE (asm_out_file, byte); | |
2854 | total_bytes++; | |
2855 | byte_buffer_in_use = 0; | |
2856 | } | |
2857 | ||
2858 | /* Advance to offset of this element. | |
2859 | Note no alignment needed in an array, since that is guaranteed | |
2860 | if each element has the proper size. */ | |
2861 | if (field != 0 && bitpos != total_bytes) | |
2862 | { | |
2863 | assemble_zeros (bitpos - total_bytes); | |
2864 | total_bytes = bitpos; | |
2865 | } | |
2866 | ||
2867 | /* Determine size this element should occupy. */ | |
2868 | if (field) | |
2869 | { | |
2870 | if (TREE_CODE (DECL_SIZE (field)) != INTEGER_CST) | |
2871 | abort (); | |
2872 | if (TREE_INT_CST_LOW (DECL_SIZE (field)) > 100000) | |
2873 | { | |
2874 | /* This avoids overflow trouble. */ | |
2875 | tree size_tree = size_binop (CEIL_DIV_EXPR, | |
2876 | DECL_SIZE (field), | |
2877 | size_int (BITS_PER_UNIT)); | |
2878 | fieldsize = TREE_INT_CST_LOW (size_tree); | |
2879 | } | |
2880 | else | |
2881 | { | |
2882 | fieldsize = TREE_INT_CST_LOW (DECL_SIZE (field)); | |
2883 | fieldsize = (fieldsize + BITS_PER_UNIT - 1) / BITS_PER_UNIT; | |
2884 | } | |
2885 | } | |
2886 | else | |
2887 | fieldsize = int_size_in_bytes (TREE_TYPE (TREE_TYPE (exp))); | |
2888 | ||
2889 | /* Output the element's initial value. */ | |
2890 | if (val == 0) | |
2891 | assemble_zeros (fieldsize); | |
2892 | else | |
2893 | output_constant (val, fieldsize); | |
2894 | ||
2895 | /* Count its size. */ | |
2896 | total_bytes += fieldsize; | |
2897 | } | |
2898 | else if (val != 0 && TREE_CODE (val) != INTEGER_CST) | |
2899 | error ("invalid initial value for member `%s'", | |
2900 | IDENTIFIER_POINTER (DECL_NAME (field))); | |
2901 | else | |
2902 | { | |
2903 | /* Element that is a bit-field. */ | |
2904 | ||
2905 | int next_offset = TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field)); | |
2906 | int end_offset | |
2907 | = (next_offset + TREE_INT_CST_LOW (DECL_SIZE (field))); | |
2908 | ||
2909 | if (val == 0) | |
2910 | val = integer_zero_node; | |
2911 | ||
2912 | /* If this field does not start in this (or, next) byte, | |
2913 | skip some bytes. */ | |
2914 | if (next_offset / BITS_PER_UNIT != total_bytes) | |
2915 | { | |
2916 | /* Output remnant of any bit field in previous bytes. */ | |
2917 | if (byte_buffer_in_use) | |
2918 | { | |
2919 | ASM_OUTPUT_BYTE (asm_out_file, byte); | |
2920 | total_bytes++; | |
2921 | byte_buffer_in_use = 0; | |
2922 | } | |
2923 | ||
2924 | /* If still not at proper byte, advance to there. */ | |
2925 | if (next_offset / BITS_PER_UNIT != total_bytes) | |
2926 | { | |
2927 | assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes); | |
2928 | total_bytes = next_offset / BITS_PER_UNIT; | |
2929 | } | |
2930 | } | |
2931 | ||
2932 | if (! byte_buffer_in_use) | |
2933 | byte = 0; | |
2934 | ||
2935 | /* We must split the element into pieces that fall within | |
2936 | separate bytes, and combine each byte with previous or | |
2937 | following bit-fields. */ | |
2938 | ||
2939 | /* next_offset is the offset n fbits from the beginning of | |
2940 | the structure to the next bit of this element to be processed. | |
2941 | end_offset is the offset of the first bit past the end of | |
2942 | this element. */ | |
2943 | while (next_offset < end_offset) | |
2944 | { | |
2945 | int this_time; | |
2946 | int shift, value; | |
2947 | int next_byte = next_offset / BITS_PER_UNIT; | |
2948 | int next_bit = next_offset % BITS_PER_UNIT; | |
2949 | ||
2950 | /* Advance from byte to byte | |
2951 | within this element when necessary. */ | |
2952 | while (next_byte != total_bytes) | |
2953 | { | |
2954 | ASM_OUTPUT_BYTE (asm_out_file, byte); | |
2955 | total_bytes++; | |
2956 | byte = 0; | |
2957 | } | |
2958 | ||
2959 | /* Number of bits we can process at once | |
2960 | (all part of the same byte). */ | |
2961 | this_time = MIN (end_offset - next_offset, | |
2962 | BITS_PER_UNIT - next_bit); | |
2963 | #if BYTES_BIG_ENDIAN | |
2964 | /* On big-endian machine, take the most significant bits | |
2965 | first (of the bits that are significant) | |
2966 | and put them into bytes from the most significant end. */ | |
2967 | shift = end_offset - next_offset - this_time; | |
2968 | /* Don't try to take a bunch of bits that cross | |
2969 | the word boundary in the INTEGER_CST. */ | |
2970 | if (shift < HOST_BITS_PER_WIDE_INT | |
2971 | && shift + this_time > HOST_BITS_PER_WIDE_INT) | |
2972 | { | |
2973 | this_time -= (HOST_BITS_PER_WIDE_INT - shift); | |
2974 | shift = HOST_BITS_PER_WIDE_INT; | |
2975 | } | |
2976 | ||
2977 | /* Now get the bits from the appropriate constant word. */ | |
2978 | if (shift < HOST_BITS_PER_WIDE_INT) | |
2979 | { | |
2980 | value = TREE_INT_CST_LOW (val); | |
2981 | } | |
2982 | else if (shift < 2 * HOST_BITS_PER_WIDE_INT) | |
2983 | { | |
2984 | value = TREE_INT_CST_HIGH (val); | |
2985 | shift -= HOST_BITS_PER_WIDE_INT; | |
2986 | } | |
2987 | else | |
2988 | abort (); | |
2989 | byte |= (((value >> shift) | |
2990 | & (((HOST_WIDE_INT) 1 << this_time) - 1)) | |
2991 | << (BITS_PER_UNIT - this_time - next_bit)); | |
2992 | #else | |
2993 | /* On little-endian machines, | |
2994 | take first the least significant bits of the value | |
2995 | and pack them starting at the least significant | |
2996 | bits of the bytes. */ | |
2997 | shift = (next_offset | |
2998 | - TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field))); | |
2999 | /* Don't try to take a bunch of bits that cross | |
3000 | the word boundary in the INTEGER_CST. */ | |
3001 | if (shift < HOST_BITS_PER_WIDE_INT | |
3002 | && shift + this_time > HOST_BITS_PER_WIDE_INT) | |
3003 | { | |
3004 | this_time -= (HOST_BITS_PER_WIDE_INT - shift); | |
3005 | shift = HOST_BITS_PER_WIDE_INT; | |
3006 | } | |
3007 | ||
3008 | /* Now get the bits from the appropriate constant word. */ | |
3009 | if (shift < HOST_BITS_PER_INT) | |
3010 | value = TREE_INT_CST_LOW (val); | |
3011 | else if (shift < 2 * HOST_BITS_PER_WIDE_INT) | |
3012 | { | |
3013 | value = TREE_INT_CST_HIGH (val); | |
3014 | shift -= HOST_BITS_PER_WIDE_INT; | |
3015 | } | |
3016 | else | |
3017 | abort (); | |
3018 | byte |= ((value >> shift) | |
3019 | & (((HOST_WIDE_INT) 1 << this_time) - 1)) << next_bit; | |
3020 | #endif | |
3021 | next_offset += this_time; | |
3022 | byte_buffer_in_use = 1; | |
3023 | } | |
3024 | } | |
3025 | } | |
3026 | if (byte_buffer_in_use) | |
3027 | { | |
3028 | ASM_OUTPUT_BYTE (asm_out_file, byte); | |
3029 | total_bytes++; | |
3030 | } | |
3031 | if (total_bytes < size) | |
3032 | assemble_zeros (size - total_bytes); | |
3033 | } |