xref: /openbsd/gnu/gcc/gcc/hard-reg-set.h (revision 404b540a)
1 /* Sets (bit vectors) of hard registers, and operations on them.
2    Copyright (C) 1987, 1992, 1994, 2000, 2003, 2004, 2005
3    Free Software Foundation, Inc.
4 
5 This file is part of GCC
6 
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
11 
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15 for more details.
16 
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING.  If not, write to the Free
19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
20 02110-1301, USA.  */
21 
22 #ifndef GCC_HARD_REG_SET_H
23 #define GCC_HARD_REG_SET_H
24 
25 /* Define the type of a set of hard registers.  */
26 
27 /* HARD_REG_ELT_TYPE is a typedef of the unsigned integral type which
28    will be used for hard reg sets, either alone or in an array.
29 
30    If HARD_REG_SET is a macro, its definition is HARD_REG_ELT_TYPE,
31    and it has enough bits to represent all the target machine's hard
32    registers.  Otherwise, it is a typedef for a suitably sized array
33    of HARD_REG_ELT_TYPEs.  HARD_REG_SET_LONGS is defined as how many.
34 
35    Note that lots of code assumes that the first part of a regset is
36    the same format as a HARD_REG_SET.  To help make sure this is true,
37    we only try the widest fast integer mode (HOST_WIDEST_FAST_INT)
38    instead of all the smaller types.  This approach loses only if
39    there are very few registers and then only in the few cases where
40    we have an array of HARD_REG_SETs, so it needn't be as complex as
41    it used to be.  */
42 
43 typedef unsigned HOST_WIDEST_FAST_INT HARD_REG_ELT_TYPE;
44 
45 #if FIRST_PSEUDO_REGISTER <= HOST_BITS_PER_WIDEST_FAST_INT
46 
47 #define HARD_REG_SET HARD_REG_ELT_TYPE
48 
49 #else
50 
51 #define HARD_REG_SET_LONGS \
52  ((FIRST_PSEUDO_REGISTER + HOST_BITS_PER_WIDEST_FAST_INT - 1)	\
53   / HOST_BITS_PER_WIDEST_FAST_INT)
54 typedef HARD_REG_ELT_TYPE HARD_REG_SET[HARD_REG_SET_LONGS];
55 
56 #endif
57 
58 /* HARD_CONST is used to cast a constant to the appropriate type
59    for use with a HARD_REG_SET.  */
60 
61 #define HARD_CONST(X) ((HARD_REG_ELT_TYPE) (X))
62 
63 /* Define macros SET_HARD_REG_BIT, CLEAR_HARD_REG_BIT and TEST_HARD_REG_BIT
64    to set, clear or test one bit in a hard reg set of type HARD_REG_SET.
65    All three take two arguments: the set and the register number.
66 
67    In the case where sets are arrays of longs, the first argument
68    is actually a pointer to a long.
69 
70    Define two macros for initializing a set:
71    CLEAR_HARD_REG_SET and SET_HARD_REG_SET.
72    These take just one argument.
73 
74    Also define macros for copying hard reg sets:
75    COPY_HARD_REG_SET and COMPL_HARD_REG_SET.
76    These take two arguments TO and FROM; they read from FROM
77    and store into TO.  COMPL_HARD_REG_SET complements each bit.
78 
79    Also define macros for combining hard reg sets:
80    IOR_HARD_REG_SET and AND_HARD_REG_SET.
81    These take two arguments TO and FROM; they read from FROM
82    and combine bitwise into TO.  Define also two variants
83    IOR_COMPL_HARD_REG_SET and AND_COMPL_HARD_REG_SET
84    which use the complement of the set FROM.
85 
86    Also define GO_IF_HARD_REG_SUBSET (X, Y, TO):
87    if X is a subset of Y, go to TO.
88 */
89 
90 #ifdef HARD_REG_SET
91 
92 #define SET_HARD_REG_BIT(SET, BIT)  \
93  ((SET) |= HARD_CONST (1) << (BIT))
94 #define CLEAR_HARD_REG_BIT(SET, BIT)  \
95  ((SET) &= ~(HARD_CONST (1) << (BIT)))
96 #define TEST_HARD_REG_BIT(SET, BIT)  \
97  (!!((SET) & (HARD_CONST (1) << (BIT))))
98 
99 #define CLEAR_HARD_REG_SET(TO) ((TO) = HARD_CONST (0))
100 #define SET_HARD_REG_SET(TO) ((TO) = ~ HARD_CONST (0))
101 
102 #define COPY_HARD_REG_SET(TO, FROM) ((TO) = (FROM))
103 #define COMPL_HARD_REG_SET(TO, FROM) ((TO) = ~(FROM))
104 
105 #define IOR_HARD_REG_SET(TO, FROM) ((TO) |= (FROM))
106 #define IOR_COMPL_HARD_REG_SET(TO, FROM) ((TO) |= ~ (FROM))
107 #define AND_HARD_REG_SET(TO, FROM) ((TO) &= (FROM))
108 #define AND_COMPL_HARD_REG_SET(TO, FROM) ((TO) &= ~ (FROM))
109 
110 #define GO_IF_HARD_REG_SUBSET(X,Y,TO) if (HARD_CONST (0) == ((X) & ~(Y))) goto TO
111 
112 #define GO_IF_HARD_REG_EQUAL(X,Y,TO) if ((X) == (Y)) goto TO
113 
114 #else
115 
116 #define UHOST_BITS_PER_WIDE_INT ((unsigned) HOST_BITS_PER_WIDEST_FAST_INT)
117 
118 #define SET_HARD_REG_BIT(SET, BIT)		\
119   ((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT]	\
120    |= HARD_CONST (1) << ((BIT) % UHOST_BITS_PER_WIDE_INT))
121 
122 #define CLEAR_HARD_REG_BIT(SET, BIT)		\
123   ((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT]	\
124    &= ~(HARD_CONST (1) << ((BIT) % UHOST_BITS_PER_WIDE_INT)))
125 
126 #define TEST_HARD_REG_BIT(SET, BIT)		\
127   (!!((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT]	\
128       & (HARD_CONST (1) << ((BIT) % UHOST_BITS_PER_WIDE_INT))))
129 
130 #if FIRST_PSEUDO_REGISTER <= 2*HOST_BITS_PER_WIDEST_FAST_INT
131 #define CLEAR_HARD_REG_SET(TO)  \
132 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);			\
133      scan_tp_[0] = 0;						\
134      scan_tp_[1] = 0; } while (0)
135 
136 #define SET_HARD_REG_SET(TO)  \
137 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);			\
138      scan_tp_[0] = -1;						\
139      scan_tp_[1] = -1; } while (0)
140 
141 #define COPY_HARD_REG_SET(TO, FROM)  \
142 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);	\
143      scan_tp_[0] = scan_fp_[0];					\
144      scan_tp_[1] = scan_fp_[1]; } while (0)
145 
146 #define COMPL_HARD_REG_SET(TO, FROM)  \
147 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
148      scan_tp_[0] = ~ scan_fp_[0];				\
149      scan_tp_[1] = ~ scan_fp_[1]; } while (0)
150 
151 #define AND_HARD_REG_SET(TO, FROM)  \
152 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
153      scan_tp_[0] &= scan_fp_[0];				\
154      scan_tp_[1] &= scan_fp_[1]; } while (0)
155 
156 #define AND_COMPL_HARD_REG_SET(TO, FROM)  \
157 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
158      scan_tp_[0] &= ~ scan_fp_[0];				\
159      scan_tp_[1] &= ~ scan_fp_[1]; } while (0)
160 
161 #define IOR_HARD_REG_SET(TO, FROM)  \
162 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
163      scan_tp_[0] |= scan_fp_[0];				\
164      scan_tp_[1] |= scan_fp_[1]; } while (0)
165 
166 #define IOR_COMPL_HARD_REG_SET(TO, FROM)  \
167 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
168      scan_tp_[0] |= ~ scan_fp_[0];				\
169      scan_tp_[1] |= ~ scan_fp_[1]; } while (0)
170 
171 #define GO_IF_HARD_REG_SUBSET(X,Y,TO)  \
172 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y); 	\
173      if ((0 == (scan_xp_[0] & ~ scan_yp_[0]))			\
174 	 && (0 == (scan_xp_[1] & ~ scan_yp_[1])))		\
175 	goto TO; } while (0)
176 
177 #define GO_IF_HARD_REG_EQUAL(X,Y,TO)  \
178 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y); 	\
179      if ((scan_xp_[0] == scan_yp_[0])				\
180 	 && (scan_xp_[1] == scan_yp_[1]))			\
181 	goto TO; } while (0)
182 
183 #else
184 #if FIRST_PSEUDO_REGISTER <= 3*HOST_BITS_PER_WIDEST_FAST_INT
185 #define CLEAR_HARD_REG_SET(TO)  \
186 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);			\
187      scan_tp_[0] = 0;						\
188      scan_tp_[1] = 0;						\
189      scan_tp_[2] = 0; } while (0)
190 
191 #define SET_HARD_REG_SET(TO)  \
192 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);			\
193      scan_tp_[0] = -1;						\
194      scan_tp_[1] = -1;						\
195      scan_tp_[2] = -1; } while (0)
196 
197 #define COPY_HARD_REG_SET(TO, FROM)  \
198 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);	\
199      scan_tp_[0] = scan_fp_[0];					\
200      scan_tp_[1] = scan_fp_[1];					\
201      scan_tp_[2] = scan_fp_[2]; } while (0)
202 
203 #define COMPL_HARD_REG_SET(TO, FROM)  \
204 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
205      scan_tp_[0] = ~ scan_fp_[0];				\
206      scan_tp_[1] = ~ scan_fp_[1];				\
207      scan_tp_[2] = ~ scan_fp_[2]; } while (0)
208 
209 #define AND_HARD_REG_SET(TO, FROM)  \
210 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
211      scan_tp_[0] &= scan_fp_[0];				\
212      scan_tp_[1] &= scan_fp_[1];				\
213      scan_tp_[2] &= scan_fp_[2]; } while (0)
214 
215 #define AND_COMPL_HARD_REG_SET(TO, FROM)  \
216 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
217      scan_tp_[0] &= ~ scan_fp_[0];				\
218      scan_tp_[1] &= ~ scan_fp_[1];				\
219      scan_tp_[2] &= ~ scan_fp_[2]; } while (0)
220 
221 #define IOR_HARD_REG_SET(TO, FROM)  \
222 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
223      scan_tp_[0] |= scan_fp_[0];				\
224      scan_tp_[1] |= scan_fp_[1];				\
225      scan_tp_[2] |= scan_fp_[2]; } while (0)
226 
227 #define IOR_COMPL_HARD_REG_SET(TO, FROM)  \
228 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
229      scan_tp_[0] |= ~ scan_fp_[0];				\
230      scan_tp_[1] |= ~ scan_fp_[1];				\
231      scan_tp_[2] |= ~ scan_fp_[2]; } while (0)
232 
233 #define GO_IF_HARD_REG_SUBSET(X,Y,TO)  \
234 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y); 	\
235      if ((0 == (scan_xp_[0] & ~ scan_yp_[0]))			\
236 	 && (0 == (scan_xp_[1] & ~ scan_yp_[1]))		\
237 	 && (0 == (scan_xp_[2] & ~ scan_yp_[2])))		\
238 	goto TO; } while (0)
239 
240 #define GO_IF_HARD_REG_EQUAL(X,Y,TO)  \
241 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y); 	\
242      if ((scan_xp_[0] == scan_yp_[0])				\
243 	 && (scan_xp_[1] == scan_yp_[1])			\
244 	 && (scan_xp_[2] == scan_yp_[2]))			\
245 	goto TO; } while (0)
246 
247 #else
248 #if FIRST_PSEUDO_REGISTER <= 4*HOST_BITS_PER_WIDEST_FAST_INT
249 #define CLEAR_HARD_REG_SET(TO)  \
250 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);			\
251      scan_tp_[0] = 0;						\
252      scan_tp_[1] = 0;						\
253      scan_tp_[2] = 0;						\
254      scan_tp_[3] = 0; } while (0)
255 
256 #define SET_HARD_REG_SET(TO)  \
257 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);			\
258      scan_tp_[0] = -1;						\
259      scan_tp_[1] = -1;						\
260      scan_tp_[2] = -1;						\
261      scan_tp_[3] = -1; } while (0)
262 
263 #define COPY_HARD_REG_SET(TO, FROM)  \
264 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);	\
265      scan_tp_[0] = scan_fp_[0];					\
266      scan_tp_[1] = scan_fp_[1];					\
267      scan_tp_[2] = scan_fp_[2];					\
268      scan_tp_[3] = scan_fp_[3]; } while (0)
269 
270 #define COMPL_HARD_REG_SET(TO, FROM)  \
271 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
272      scan_tp_[0] = ~ scan_fp_[0];				\
273      scan_tp_[1] = ~ scan_fp_[1];				\
274      scan_tp_[2] = ~ scan_fp_[2];				\
275      scan_tp_[3] = ~ scan_fp_[3]; } while (0)
276 
277 #define AND_HARD_REG_SET(TO, FROM)  \
278 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
279      scan_tp_[0] &= scan_fp_[0];				\
280      scan_tp_[1] &= scan_fp_[1];				\
281      scan_tp_[2] &= scan_fp_[2];				\
282      scan_tp_[3] &= scan_fp_[3]; } while (0)
283 
284 #define AND_COMPL_HARD_REG_SET(TO, FROM)  \
285 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
286      scan_tp_[0] &= ~ scan_fp_[0];				\
287      scan_tp_[1] &= ~ scan_fp_[1];				\
288      scan_tp_[2] &= ~ scan_fp_[2];				\
289      scan_tp_[3] &= ~ scan_fp_[3]; } while (0)
290 
291 #define IOR_HARD_REG_SET(TO, FROM)  \
292 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
293      scan_tp_[0] |= scan_fp_[0];				\
294      scan_tp_[1] |= scan_fp_[1];				\
295      scan_tp_[2] |= scan_fp_[2];				\
296      scan_tp_[3] |= scan_fp_[3]; } while (0)
297 
298 #define IOR_COMPL_HARD_REG_SET(TO, FROM)  \
299 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
300      scan_tp_[0] |= ~ scan_fp_[0];				\
301      scan_tp_[1] |= ~ scan_fp_[1];				\
302      scan_tp_[2] |= ~ scan_fp_[2];				\
303      scan_tp_[3] |= ~ scan_fp_[3]; } while (0)
304 
305 #define GO_IF_HARD_REG_SUBSET(X,Y,TO)  \
306 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y); 	\
307      if ((0 == (scan_xp_[0] & ~ scan_yp_[0]))			\
308 	 && (0 == (scan_xp_[1] & ~ scan_yp_[1]))		\
309 	 && (0 == (scan_xp_[2] & ~ scan_yp_[2]))		\
310 	 && (0 == (scan_xp_[3] & ~ scan_yp_[3])))		\
311 	goto TO; } while (0)
312 
313 #define GO_IF_HARD_REG_EQUAL(X,Y,TO)  \
314 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y); 	\
315      if ((scan_xp_[0] == scan_yp_[0])				\
316 	 && (scan_xp_[1] == scan_yp_[1])			\
317 	 && (scan_xp_[2] == scan_yp_[2])			\
318 	 && (scan_xp_[3] == scan_yp_[3]))			\
319 	goto TO; } while (0)
320 
321 #else /* FIRST_PSEUDO_REGISTER > 3*HOST_BITS_PER_WIDEST_FAST_INT */
322 
323 #define CLEAR_HARD_REG_SET(TO)  \
324 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);			\
325      int i;							\
326      for (i = 0; i < HARD_REG_SET_LONGS; i++)			\
327        *scan_tp_++ = 0; } while (0)
328 
329 #define SET_HARD_REG_SET(TO)  \
330 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);			\
331      int i;							\
332      for (i = 0; i < HARD_REG_SET_LONGS; i++)			\
333        *scan_tp_++ = -1; } while (0)
334 
335 #define COPY_HARD_REG_SET(TO, FROM)  \
336 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
337      int i;							\
338      for (i = 0; i < HARD_REG_SET_LONGS; i++)			\
339        *scan_tp_++ = *scan_fp_++; } while (0)
340 
341 #define COMPL_HARD_REG_SET(TO, FROM)  \
342 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
343      int i;							\
344      for (i = 0; i < HARD_REG_SET_LONGS; i++)			\
345        *scan_tp_++ = ~ *scan_fp_++; } while (0)
346 
347 #define AND_HARD_REG_SET(TO, FROM)  \
348 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
349      int i;							\
350      for (i = 0; i < HARD_REG_SET_LONGS; i++)			\
351        *scan_tp_++ &= *scan_fp_++; } while (0)
352 
353 #define AND_COMPL_HARD_REG_SET(TO, FROM)  \
354 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
355      int i;							\
356      for (i = 0; i < HARD_REG_SET_LONGS; i++)			\
357        *scan_tp_++ &= ~ *scan_fp_++; } while (0)
358 
359 #define IOR_HARD_REG_SET(TO, FROM)  \
360 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
361      int i;							\
362      for (i = 0; i < HARD_REG_SET_LONGS; i++)			\
363        *scan_tp_++ |= *scan_fp_++; } while (0)
364 
365 #define IOR_COMPL_HARD_REG_SET(TO, FROM)  \
366 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); 	\
367      int i;							\
368      for (i = 0; i < HARD_REG_SET_LONGS; i++)			\
369        *scan_tp_++ |= ~ *scan_fp_++; } while (0)
370 
371 #define GO_IF_HARD_REG_SUBSET(X,Y,TO)  \
372 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y); 	\
373      int i;							\
374      for (i = 0; i < HARD_REG_SET_LONGS; i++)			\
375        if (0 != (*scan_xp_++ & ~ *scan_yp_++)) break;		\
376      if (i == HARD_REG_SET_LONGS) goto TO; } while (0)
377 
378 #define GO_IF_HARD_REG_EQUAL(X,Y,TO)  \
379 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y); 	\
380      int i;							\
381      for (i = 0; i < HARD_REG_SET_LONGS; i++)			\
382        if (*scan_xp_++ != *scan_yp_++) break;			\
383      if (i == HARD_REG_SET_LONGS) goto TO; } while (0)
384 
385 #endif
386 #endif
387 #endif
388 #endif
389 
390 /* Define some standard sets of registers.  */
391 
392 /* Indexed by hard register number, contains 1 for registers
393    that are fixed use (stack pointer, pc, frame pointer, etc.).
394    These are the registers that cannot be used to allocate
395    a pseudo reg whose life does not cross calls.  */
396 
397 extern char fixed_regs[FIRST_PSEUDO_REGISTER];
398 
399 /* The same info as a HARD_REG_SET.  */
400 
401 extern HARD_REG_SET fixed_reg_set;
402 
403 /* Indexed by hard register number, contains 1 for registers
404    that are fixed use or are clobbered by function calls.
405    These are the registers that cannot be used to allocate
406    a pseudo reg whose life crosses calls.  */
407 
408 extern char call_used_regs[FIRST_PSEUDO_REGISTER];
409 
410 #ifdef CALL_REALLY_USED_REGISTERS
411 extern char call_really_used_regs[];
412 #endif
413 
414 /* The same info as a HARD_REG_SET.  */
415 
416 extern HARD_REG_SET call_used_reg_set;
417 
418 /* Registers that we don't want to caller save.  */
419 extern HARD_REG_SET losing_caller_save_reg_set;
420 
421 /* Indexed by hard register number, contains 1 for registers that are
422    fixed use -- i.e. in fixed_regs -- or a function value return register
423    or TARGET_STRUCT_VALUE_RTX or STATIC_CHAIN_REGNUM.  These are the
424    registers that cannot hold quantities across calls even if we are
425    willing to save and restore them.  */
426 
427 extern char call_fixed_regs[FIRST_PSEUDO_REGISTER];
428 
429 /* The same info as a HARD_REG_SET.  */
430 
431 extern HARD_REG_SET call_fixed_reg_set;
432 
433 /* Indexed by hard register number, contains 1 for registers
434    that are being used for global register decls.
435    These must be exempt from ordinary flow analysis
436    and are also considered fixed.  */
437 
438 extern char global_regs[FIRST_PSEUDO_REGISTER];
439 
440 /* Contains 1 for registers that are set or clobbered by calls.  */
441 /* ??? Ideally, this would be just call_used_regs plus global_regs, but
442    for someone's bright idea to have call_used_regs strictly include
443    fixed_regs.  Which leaves us guessing as to the set of fixed_regs
444    that are actually preserved.  We know for sure that those associated
445    with the local stack frame are safe, but scant others.  */
446 
447 extern HARD_REG_SET regs_invalidated_by_call;
448 
449 #ifdef REG_ALLOC_ORDER
450 /* Table of register numbers in the order in which to try to use them.  */
451 
452 extern int reg_alloc_order[FIRST_PSEUDO_REGISTER];
453 
454 /* The inverse of reg_alloc_order.  */
455 
456 extern int inv_reg_alloc_order[FIRST_PSEUDO_REGISTER];
457 #endif
458 
459 /* For each reg class, a HARD_REG_SET saying which registers are in it.  */
460 
461 extern HARD_REG_SET reg_class_contents[N_REG_CLASSES];
462 
463 /* For each reg class, number of regs it contains.  */
464 
465 extern unsigned int reg_class_size[N_REG_CLASSES];
466 
467 /* For each pair of reg classes,
468    a largest reg class contained in their union.  */
469 
470 extern enum reg_class reg_class_subunion[N_REG_CLASSES][N_REG_CLASSES];
471 
472 /* For each pair of reg classes,
473    the smallest reg class that contains their union.  */
474 
475 extern enum reg_class reg_class_superunion[N_REG_CLASSES][N_REG_CLASSES];
476 
477 /* Vector indexed by hardware reg giving its name.  */
478 
479 extern const char * reg_names[FIRST_PSEUDO_REGISTER];
480 
481 /* Vector indexed by reg class giving its name.  */
482 
483 extern const char * reg_class_names[];
484 
485 /* Given a hard REGN a FROM mode and a TO mode, return nonzero if
486    REGN cannot change modes between the specified modes.  */
487 #define REG_CANNOT_CHANGE_MODE_P(REGN, FROM, TO)                          \
488          CANNOT_CHANGE_MODE_CLASS (FROM, TO, REGNO_REG_CLASS (REGN))
489 
490 #endif /* ! GCC_HARD_REG_SET_H */
491