1 /* Sets (bit vectors) of hard registers, and operations on them.
2 Copyright (C) 1987, 1992, 1994, 2000, 2003, 2004, 2005, 2007, 2008, 2009
3 Free Software Foundation, Inc.
5 This file is part of GCC
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 #ifndef GCC_HARD_REG_SET_H
22 #define GCC_HARD_REG_SET_H
24 /* Define the type of a set of hard registers. */
26 /* HARD_REG_ELT_TYPE is a typedef of the unsigned integral type which
27 will be used for hard reg sets, either alone or in an array.
29 If HARD_REG_SET is a macro, its definition is HARD_REG_ELT_TYPE,
30 and it has enough bits to represent all the target machine's hard
31 registers. Otherwise, it is a typedef for a suitably sized array
32 of HARD_REG_ELT_TYPEs. HARD_REG_SET_LONGS is defined as how many.
34 Note that lots of code assumes that the first part of a regset is
35 the same format as a HARD_REG_SET. To help make sure this is true,
36 we only try the widest fast integer mode (HOST_WIDEST_FAST_INT)
37 instead of all the smaller types. This approach loses only if
38 there are very few registers and then only in the few cases where
39 we have an array of HARD_REG_SETs, so it needn't be as complex as
42 typedef unsigned HOST_WIDEST_FAST_INT HARD_REG_ELT_TYPE
;
44 #if FIRST_PSEUDO_REGISTER <= HOST_BITS_PER_WIDEST_FAST_INT
46 #define HARD_REG_SET HARD_REG_ELT_TYPE
50 #define HARD_REG_SET_LONGS \
51 ((FIRST_PSEUDO_REGISTER + HOST_BITS_PER_WIDEST_FAST_INT - 1) \
52 / HOST_BITS_PER_WIDEST_FAST_INT)
53 typedef HARD_REG_ELT_TYPE HARD_REG_SET
[HARD_REG_SET_LONGS
];
57 /* HARD_CONST is used to cast a constant to the appropriate type
58 for use with a HARD_REG_SET. */
60 #define HARD_CONST(X) ((HARD_REG_ELT_TYPE) (X))
62 /* Define macros SET_HARD_REG_BIT, CLEAR_HARD_REG_BIT and TEST_HARD_REG_BIT
63 to set, clear or test one bit in a hard reg set of type HARD_REG_SET.
64 All three take two arguments: the set and the register number.
66 In the case where sets are arrays of longs, the first argument
67 is actually a pointer to a long.
69 Define two macros for initializing a set:
70 CLEAR_HARD_REG_SET and SET_HARD_REG_SET.
71 These take just one argument.
73 Also define macros for copying hard reg sets:
74 COPY_HARD_REG_SET and COMPL_HARD_REG_SET.
75 These take two arguments TO and FROM; they read from FROM
76 and store into TO. COMPL_HARD_REG_SET complements each bit.
78 Also define macros for combining hard reg sets:
79 IOR_HARD_REG_SET and AND_HARD_REG_SET.
80 These take two arguments TO and FROM; they read from FROM
81 and combine bitwise into TO. Define also two variants
82 IOR_COMPL_HARD_REG_SET and AND_COMPL_HARD_REG_SET
83 which use the complement of the set FROM.
87 hard_reg_set_subset_p (X, Y), which returns true if X is a subset of Y.
88 hard_reg_set_equal_p (X, Y), which returns true if X and Y are equal.
89 hard_reg_set_intersect_p (X, Y), which returns true if X and Y intersect.
90 hard_reg_set_empty_p (X), which returns true if X is empty. */
92 #define UHOST_BITS_PER_WIDE_INT ((unsigned) HOST_BITS_PER_WIDEST_FAST_INT)
96 #define SET_HARD_REG_BIT(SET, BIT) \
97 ((SET) |= HARD_CONST (1) << (BIT))
98 #define CLEAR_HARD_REG_BIT(SET, BIT) \
99 ((SET) &= ~(HARD_CONST (1) << (BIT)))
100 #define TEST_HARD_REG_BIT(SET, BIT) \
101 (!!((SET) & (HARD_CONST (1) << (BIT))))
103 #define CLEAR_HARD_REG_SET(TO) ((TO) = HARD_CONST (0))
104 #define SET_HARD_REG_SET(TO) ((TO) = ~ HARD_CONST (0))
106 #define COPY_HARD_REG_SET(TO, FROM) ((TO) = (FROM))
107 #define COMPL_HARD_REG_SET(TO, FROM) ((TO) = ~(FROM))
109 #define IOR_HARD_REG_SET(TO, FROM) ((TO) |= (FROM))
110 #define IOR_COMPL_HARD_REG_SET(TO, FROM) ((TO) |= ~ (FROM))
111 #define AND_HARD_REG_SET(TO, FROM) ((TO) &= (FROM))
112 #define AND_COMPL_HARD_REG_SET(TO, FROM) ((TO) &= ~ (FROM))
115 hard_reg_set_subset_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
117 return (x
& ~y
) == HARD_CONST (0);
121 hard_reg_set_equal_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
127 hard_reg_set_intersect_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
129 return (x
& y
) != HARD_CONST (0);
133 hard_reg_set_empty_p (const HARD_REG_SET x
)
135 return x
== HARD_CONST (0);
140 #define SET_HARD_REG_BIT(SET, BIT) \
141 ((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT] \
142 |= HARD_CONST (1) << ((BIT) % UHOST_BITS_PER_WIDE_INT))
144 #define CLEAR_HARD_REG_BIT(SET, BIT) \
145 ((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT] \
146 &= ~(HARD_CONST (1) << ((BIT) % UHOST_BITS_PER_WIDE_INT)))
148 #define TEST_HARD_REG_BIT(SET, BIT) \
149 (!!((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT] \
150 & (HARD_CONST (1) << ((BIT) % UHOST_BITS_PER_WIDE_INT))))
152 #if FIRST_PSEUDO_REGISTER <= 2*HOST_BITS_PER_WIDEST_FAST_INT
153 #define CLEAR_HARD_REG_SET(TO) \
154 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO); \
156 scan_tp_[1] = 0; } while (0)
158 #define SET_HARD_REG_SET(TO) \
159 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO); \
161 scan_tp_[1] = -1; } while (0)
163 #define COPY_HARD_REG_SET(TO, FROM) \
164 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
165 scan_tp_[0] = scan_fp_[0]; \
166 scan_tp_[1] = scan_fp_[1]; } while (0)
168 #define COMPL_HARD_REG_SET(TO, FROM) \
169 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
170 scan_tp_[0] = ~ scan_fp_[0]; \
171 scan_tp_[1] = ~ scan_fp_[1]; } while (0)
173 #define AND_HARD_REG_SET(TO, FROM) \
174 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
175 scan_tp_[0] &= scan_fp_[0]; \
176 scan_tp_[1] &= scan_fp_[1]; } while (0)
178 #define AND_COMPL_HARD_REG_SET(TO, FROM) \
179 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
180 scan_tp_[0] &= ~ scan_fp_[0]; \
181 scan_tp_[1] &= ~ scan_fp_[1]; } while (0)
183 #define IOR_HARD_REG_SET(TO, FROM) \
184 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
185 scan_tp_[0] |= scan_fp_[0]; \
186 scan_tp_[1] |= scan_fp_[1]; } while (0)
188 #define IOR_COMPL_HARD_REG_SET(TO, FROM) \
189 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
190 scan_tp_[0] |= ~ scan_fp_[0]; \
191 scan_tp_[1] |= ~ scan_fp_[1]; } while (0)
194 hard_reg_set_subset_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
196 return (x
[0] & ~y
[0]) == 0 && (x
[1] & ~y
[1]) == 0;
200 hard_reg_set_equal_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
202 return x
[0] == y
[0] && x
[1] == y
[1];
206 hard_reg_set_intersect_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
208 return (x
[0] & y
[0]) != 0 || (x
[1] & y
[1]) != 0;
212 hard_reg_set_empty_p (const HARD_REG_SET x
)
214 return x
[0] == 0 && x
[1] == 0;
218 #if FIRST_PSEUDO_REGISTER <= 3*HOST_BITS_PER_WIDEST_FAST_INT
219 #define CLEAR_HARD_REG_SET(TO) \
220 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO); \
223 scan_tp_[2] = 0; } while (0)
225 #define SET_HARD_REG_SET(TO) \
226 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO); \
229 scan_tp_[2] = -1; } while (0)
231 #define COPY_HARD_REG_SET(TO, FROM) \
232 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
233 scan_tp_[0] = scan_fp_[0]; \
234 scan_tp_[1] = scan_fp_[1]; \
235 scan_tp_[2] = scan_fp_[2]; } while (0)
237 #define COMPL_HARD_REG_SET(TO, FROM) \
238 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
239 scan_tp_[0] = ~ scan_fp_[0]; \
240 scan_tp_[1] = ~ scan_fp_[1]; \
241 scan_tp_[2] = ~ scan_fp_[2]; } while (0)
243 #define AND_HARD_REG_SET(TO, FROM) \
244 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
245 scan_tp_[0] &= scan_fp_[0]; \
246 scan_tp_[1] &= scan_fp_[1]; \
247 scan_tp_[2] &= scan_fp_[2]; } while (0)
249 #define AND_COMPL_HARD_REG_SET(TO, FROM) \
250 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
251 scan_tp_[0] &= ~ scan_fp_[0]; \
252 scan_tp_[1] &= ~ scan_fp_[1]; \
253 scan_tp_[2] &= ~ scan_fp_[2]; } while (0)
255 #define IOR_HARD_REG_SET(TO, FROM) \
256 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
257 scan_tp_[0] |= scan_fp_[0]; \
258 scan_tp_[1] |= scan_fp_[1]; \
259 scan_tp_[2] |= scan_fp_[2]; } while (0)
261 #define IOR_COMPL_HARD_REG_SET(TO, FROM) \
262 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
263 scan_tp_[0] |= ~ scan_fp_[0]; \
264 scan_tp_[1] |= ~ scan_fp_[1]; \
265 scan_tp_[2] |= ~ scan_fp_[2]; } while (0)
268 hard_reg_set_subset_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
270 return ((x
[0] & ~y
[0]) == 0
271 && (x
[1] & ~y
[1]) == 0
272 && (x
[2] & ~y
[2]) == 0);
276 hard_reg_set_equal_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
278 return x
[0] == y
[0] && x
[1] == y
[1] && x
[2] == y
[2];
282 hard_reg_set_intersect_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
284 return ((x
[0] & y
[0]) != 0
285 || (x
[1] & y
[1]) != 0
286 || (x
[2] & y
[2]) != 0);
290 hard_reg_set_empty_p (const HARD_REG_SET x
)
292 return x
[0] == 0 && x
[1] == 0 && x
[2] == 0;
296 #if FIRST_PSEUDO_REGISTER <= 4*HOST_BITS_PER_WIDEST_FAST_INT
297 #define CLEAR_HARD_REG_SET(TO) \
298 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO); \
302 scan_tp_[3] = 0; } while (0)
304 #define SET_HARD_REG_SET(TO) \
305 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO); \
309 scan_tp_[3] = -1; } while (0)
311 #define COPY_HARD_REG_SET(TO, FROM) \
312 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
313 scan_tp_[0] = scan_fp_[0]; \
314 scan_tp_[1] = scan_fp_[1]; \
315 scan_tp_[2] = scan_fp_[2]; \
316 scan_tp_[3] = scan_fp_[3]; } while (0)
318 #define COMPL_HARD_REG_SET(TO, FROM) \
319 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
320 scan_tp_[0] = ~ scan_fp_[0]; \
321 scan_tp_[1] = ~ scan_fp_[1]; \
322 scan_tp_[2] = ~ scan_fp_[2]; \
323 scan_tp_[3] = ~ scan_fp_[3]; } while (0)
325 #define AND_HARD_REG_SET(TO, FROM) \
326 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
327 scan_tp_[0] &= scan_fp_[0]; \
328 scan_tp_[1] &= scan_fp_[1]; \
329 scan_tp_[2] &= scan_fp_[2]; \
330 scan_tp_[3] &= scan_fp_[3]; } while (0)
332 #define AND_COMPL_HARD_REG_SET(TO, FROM) \
333 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
334 scan_tp_[0] &= ~ scan_fp_[0]; \
335 scan_tp_[1] &= ~ scan_fp_[1]; \
336 scan_tp_[2] &= ~ scan_fp_[2]; \
337 scan_tp_[3] &= ~ scan_fp_[3]; } while (0)
339 #define IOR_HARD_REG_SET(TO, FROM) \
340 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
341 scan_tp_[0] |= scan_fp_[0]; \
342 scan_tp_[1] |= scan_fp_[1]; \
343 scan_tp_[2] |= scan_fp_[2]; \
344 scan_tp_[3] |= scan_fp_[3]; } while (0)
346 #define IOR_COMPL_HARD_REG_SET(TO, FROM) \
347 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
348 scan_tp_[0] |= ~ scan_fp_[0]; \
349 scan_tp_[1] |= ~ scan_fp_[1]; \
350 scan_tp_[2] |= ~ scan_fp_[2]; \
351 scan_tp_[3] |= ~ scan_fp_[3]; } while (0)
354 hard_reg_set_subset_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
356 return ((x
[0] & ~y
[0]) == 0
357 && (x
[1] & ~y
[1]) == 0
358 && (x
[2] & ~y
[2]) == 0
359 && (x
[3] & ~y
[3]) == 0);
363 hard_reg_set_equal_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
365 return x
[0] == y
[0] && x
[1] == y
[1] && x
[2] == y
[2] && x
[3] == y
[3];
369 hard_reg_set_intersect_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
371 return ((x
[0] & y
[0]) != 0
372 || (x
[1] & y
[1]) != 0
373 || (x
[2] & y
[2]) != 0
374 || (x
[3] & y
[3]) != 0);
378 hard_reg_set_empty_p (const HARD_REG_SET x
)
380 return x
[0] == 0 && x
[1] == 0 && x
[2] == 0 && x
[3] == 0;
383 #else /* FIRST_PSEUDO_REGISTER > 4*HOST_BITS_PER_WIDEST_FAST_INT */
385 #define CLEAR_HARD_REG_SET(TO) \
386 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO); \
388 for (i = 0; i < HARD_REG_SET_LONGS; i++) \
389 *scan_tp_++ = 0; } while (0)
391 #define SET_HARD_REG_SET(TO) \
392 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO); \
394 for (i = 0; i < HARD_REG_SET_LONGS; i++) \
395 *scan_tp_++ = -1; } while (0)
397 #define COPY_HARD_REG_SET(TO, FROM) \
398 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
400 for (i = 0; i < HARD_REG_SET_LONGS; i++) \
401 *scan_tp_++ = *scan_fp_++; } while (0)
403 #define COMPL_HARD_REG_SET(TO, FROM) \
404 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
406 for (i = 0; i < HARD_REG_SET_LONGS; i++) \
407 *scan_tp_++ = ~ *scan_fp_++; } while (0)
409 #define AND_HARD_REG_SET(TO, FROM) \
410 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
412 for (i = 0; i < HARD_REG_SET_LONGS; i++) \
413 *scan_tp_++ &= *scan_fp_++; } while (0)
415 #define AND_COMPL_HARD_REG_SET(TO, FROM) \
416 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
418 for (i = 0; i < HARD_REG_SET_LONGS; i++) \
419 *scan_tp_++ &= ~ *scan_fp_++; } while (0)
421 #define IOR_HARD_REG_SET(TO, FROM) \
422 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
424 for (i = 0; i < HARD_REG_SET_LONGS; i++) \
425 *scan_tp_++ |= *scan_fp_++; } while (0)
427 #define IOR_COMPL_HARD_REG_SET(TO, FROM) \
428 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
430 for (i = 0; i < HARD_REG_SET_LONGS; i++) \
431 *scan_tp_++ |= ~ *scan_fp_++; } while (0)
434 hard_reg_set_subset_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
438 for (i
= 0; i
< HARD_REG_SET_LONGS
; i
++)
439 if ((x
[i
] & ~y
[i
]) != 0)
445 hard_reg_set_equal_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
449 for (i
= 0; i
< HARD_REG_SET_LONGS
; i
++)
456 hard_reg_set_intersect_p (const HARD_REG_SET x
, const HARD_REG_SET y
)
460 for (i
= 0; i
< HARD_REG_SET_LONGS
; i
++)
461 if ((x
[i
] & y
[i
]) != 0)
467 hard_reg_set_empty_p (const HARD_REG_SET x
)
471 for (i
= 0; i
< HARD_REG_SET_LONGS
; i
++)
482 /* Iterator for hard register sets. */
486 /* Pointer to the current element. */
487 HARD_REG_ELT_TYPE
*pelt
;
489 /* The length of the set. */
490 unsigned short length
;
492 /* Word within the current element. */
493 unsigned short word_no
;
495 /* Contents of the actually processed word. When finding next bit
496 it is shifted right, so that the actual bit is always the least
497 significant bit of ACTUAL. */
498 HARD_REG_ELT_TYPE bits
;
499 } hard_reg_set_iterator
;
501 #define HARD_REG_ELT_BITS UHOST_BITS_PER_WIDE_INT
503 /* The implementation of the iterator functions is fully analogous to
504 the bitmap iterators. */
506 hard_reg_set_iter_init (hard_reg_set_iterator
*iter
, HARD_REG_SET set
,
507 unsigned min
, unsigned *regno
)
509 #ifdef HARD_REG_SET_LONGS
511 iter
->length
= HARD_REG_SET_LONGS
;
516 iter
->word_no
= min
/ HARD_REG_ELT_BITS
;
517 if (iter
->word_no
< iter
->length
)
519 iter
->bits
= iter
->pelt
[iter
->word_no
];
520 iter
->bits
>>= min
% HARD_REG_ELT_BITS
;
522 /* This is required for correct search of the next bit. */
529 hard_reg_set_iter_set (hard_reg_set_iterator
*iter
, unsigned *regno
)
533 /* Return false when we're advanced past the end of the set. */
534 if (iter
->word_no
>= iter
->length
)
539 /* Find the correct bit and return it. */
540 while (!(iter
->bits
& 1))
545 return (*regno
< FIRST_PSEUDO_REGISTER
);
548 /* Round to the beginning of the next word. */
549 *regno
= (*regno
+ HARD_REG_ELT_BITS
- 1);
550 *regno
-= *regno
% HARD_REG_ELT_BITS
;
552 /* Find the next non-zero word. */
553 while (++iter
->word_no
< iter
->length
)
555 iter
->bits
= iter
->pelt
[iter
->word_no
];
558 *regno
+= HARD_REG_ELT_BITS
;
564 hard_reg_set_iter_next (hard_reg_set_iterator
*iter
, unsigned *regno
)
570 #define EXECUTE_IF_SET_IN_HARD_REG_SET(SET, MIN, REGNUM, ITER) \
571 for (hard_reg_set_iter_init (&(ITER), (SET), (MIN), &(REGNUM)); \
572 hard_reg_set_iter_set (&(ITER), &(REGNUM)); \
573 hard_reg_set_iter_next (&(ITER), &(REGNUM)))
576 /* Define some standard sets of registers. */
578 /* Indexed by hard register number, contains 1 for registers
579 that are fixed use (stack pointer, pc, frame pointer, etc.).
580 These are the registers that cannot be used to allocate
581 a pseudo reg whose life does not cross calls. */
583 extern char fixed_regs
[FIRST_PSEUDO_REGISTER
];
585 /* The same info as a HARD_REG_SET. */
587 extern HARD_REG_SET fixed_reg_set
;
589 /* Indexed by hard register number, contains 1 for registers
590 that are fixed use or are clobbered by function calls.
591 These are the registers that cannot be used to allocate
592 a pseudo reg whose life crosses calls. */
594 extern char call_used_regs
[FIRST_PSEUDO_REGISTER
];
596 #ifdef CALL_REALLY_USED_REGISTERS
597 extern char call_really_used_regs
[];
600 /* The same info as a HARD_REG_SET. */
602 extern HARD_REG_SET call_used_reg_set
;
604 /* Contains registers that are fixed use -- i.e. in fixed_reg_set -- or
605 a function value return register or TARGET_STRUCT_VALUE_RTX or
606 STATIC_CHAIN_REGNUM. These are the registers that cannot hold quantities
607 across calls even if we are willing to save and restore them. */
609 extern HARD_REG_SET call_fixed_reg_set
;
611 /* Indexed by hard register number, contains 1 for registers
612 that are being used for global register decls.
613 These must be exempt from ordinary flow analysis
614 and are also considered fixed. */
616 extern char global_regs
[FIRST_PSEUDO_REGISTER
];
618 /* Contains 1 for registers that are set or clobbered by calls. */
619 /* ??? Ideally, this would be just call_used_regs plus global_regs, but
620 for someone's bright idea to have call_used_regs strictly include
621 fixed_regs. Which leaves us guessing as to the set of fixed_regs
622 that are actually preserved. We know for sure that those associated
623 with the local stack frame are safe, but scant others. */
625 extern HARD_REG_SET regs_invalidated_by_call
;
627 /* Call used hard registers which can not be saved because there is no
630 extern HARD_REG_SET no_caller_save_reg_set
;
632 #ifdef REG_ALLOC_ORDER
633 /* Table of register numbers in the order in which to try to use them. */
635 extern int reg_alloc_order
[FIRST_PSEUDO_REGISTER
];
637 /* The inverse of reg_alloc_order. */
639 extern int inv_reg_alloc_order
[FIRST_PSEUDO_REGISTER
];
642 /* For each reg class, a HARD_REG_SET saying which registers are in it. */
644 extern HARD_REG_SET reg_class_contents
[N_REG_CLASSES
];
646 /* For each reg class, number of regs it contains. */
648 extern unsigned int reg_class_size
[N_REG_CLASSES
];
650 /* For each reg class, table listing all the classes contained in it. */
652 extern enum reg_class reg_class_subclasses
[N_REG_CLASSES
][N_REG_CLASSES
];
654 /* For each pair of reg classes,
655 a largest reg class contained in their union. */
657 extern enum reg_class reg_class_subunion
[N_REG_CLASSES
][N_REG_CLASSES
];
659 /* For each pair of reg classes,
660 the smallest reg class that contains their union. */
662 extern enum reg_class reg_class_superunion
[N_REG_CLASSES
][N_REG_CLASSES
];
664 /* Vector indexed by hardware reg giving its name. */
666 extern const char * reg_names
[FIRST_PSEUDO_REGISTER
];
668 /* Vector indexed by reg class giving its name. */
670 extern const char * reg_class_names
[];
672 /* Given a hard REGN a FROM mode and a TO mode, return nonzero if
673 REGN cannot change modes between the specified modes. */
674 #define REG_CANNOT_CHANGE_MODE_P(REGN, FROM, TO) \
675 CANNOT_CHANGE_MODE_CLASS (FROM, TO, REGNO_REG_CLASS (REGN))
677 #endif /* ! GCC_HARD_REG_SET_H */