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eab89b90 RK |
1 | /* Search an insn for pseudo regs that must be in hard regs and are not. |
2 | Copyright (C) 1987, 1988, 1989, 1992 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 contains subroutines used only from the file reload1.c. | |
22 | It knows how to scan one insn for operands and values | |
23 | that need to be copied into registers to make valid code. | |
24 | It also finds other operands and values which are valid | |
25 | but for which equivalent values in registers exist and | |
26 | ought to be used instead. | |
27 | ||
28 | Before processing the first insn of the function, call `init_reload'. | |
29 | ||
30 | To scan an insn, call `find_reloads'. This does two things: | |
31 | 1. sets up tables describing which values must be reloaded | |
32 | for this insn, and what kind of hard regs they must be reloaded into; | |
33 | 2. optionally record the locations where those values appear in | |
34 | the data, so they can be replaced properly later. | |
35 | This is done only if the second arg to `find_reloads' is nonzero. | |
36 | ||
37 | The third arg to `find_reloads' specifies the number of levels | |
38 | of indirect addressing supported by the machine. If it is zero, | |
39 | indirect addressing is not valid. If it is one, (MEM (REG n)) | |
40 | is valid even if (REG n) did not get a hard register; if it is two, | |
41 | (MEM (MEM (REG n))) is also valid even if (REG n) did not get a | |
42 | hard register, and similarly for higher values. | |
43 | ||
44 | Then you must choose the hard regs to reload those pseudo regs into, | |
45 | and generate appropriate load insns before this insn and perhaps | |
46 | also store insns after this insn. Set up the array `reload_reg_rtx' | |
47 | to contain the REG rtx's for the registers you used. In some | |
48 | cases `find_reloads' will return a nonzero value in `reload_reg_rtx' | |
49 | for certain reloads. Then that tells you which register to use, | |
50 | so you do not need to allocate one. But you still do need to add extra | |
51 | instructions to copy the value into and out of that register. | |
52 | ||
53 | Finally you must call `subst_reloads' to substitute the reload reg rtx's | |
54 | into the locations already recorded. | |
55 | ||
56 | NOTE SIDE EFFECTS: | |
57 | ||
58 | find_reloads can alter the operands of the instruction it is called on. | |
59 | ||
60 | 1. Two operands of any sort may be interchanged, if they are in a | |
61 | commutative instruction. | |
62 | This happens only if find_reloads thinks the instruction will compile | |
63 | better that way. | |
64 | ||
65 | 2. Pseudo-registers that are equivalent to constants are replaced | |
66 | with those constants if they are not in hard registers. | |
67 | ||
68 | 1 happens every time find_reloads is called. | |
69 | 2 happens only when REPLACE is 1, which is only when | |
70 | actually doing the reloads, not when just counting them. | |
71 | ||
72 | ||
73 | Using a reload register for several reloads in one insn: | |
74 | ||
75 | When an insn has reloads, it is considered as having three parts: | |
76 | the input reloads, the insn itself after reloading, and the output reloads. | |
77 | Reloads of values used in memory addresses are often needed for only one part. | |
78 | ||
79 | When this is so, reload_when_needed records which part needs the reload. | |
80 | Two reloads for different parts of the insn can share the same reload | |
81 | register. | |
82 | ||
83 | When a reload is used for addresses in multiple parts, or when it is | |
84 | an ordinary operand, it is classified as RELOAD_OTHER, and cannot share | |
85 | a register with any other reload. */ | |
86 | ||
87 | #define REG_OK_STRICT | |
88 | ||
89 | #include "config.h" | |
90 | #include "rtl.h" | |
91 | #include "insn-config.h" | |
92 | #include "insn-codes.h" | |
93 | #include "recog.h" | |
94 | #include "reload.h" | |
95 | #include "regs.h" | |
96 | #include "hard-reg-set.h" | |
97 | #include "flags.h" | |
98 | #include "real.h" | |
99 | ||
100 | #ifndef REGISTER_MOVE_COST | |
101 | #define REGISTER_MOVE_COST(x, y) 2 | |
102 | #endif | |
103 | \f | |
104 | /* The variables set up by `find_reloads' are: | |
105 | ||
106 | n_reloads number of distinct reloads needed; max reload # + 1 | |
107 | tables indexed by reload number | |
108 | reload_in rtx for value to reload from | |
109 | reload_out rtx for where to store reload-reg afterward if nec | |
110 | (often the same as reload_in) | |
111 | reload_reg_class enum reg_class, saying what regs to reload into | |
112 | reload_inmode enum machine_mode; mode this operand should have | |
113 | when reloaded, on input. | |
114 | reload_outmode enum machine_mode; mode this operand should have | |
115 | when reloaded, on output. | |
116 | reload_strict_low char; currently always zero; used to mean that this | |
117 | reload is inside a STRICT_LOW_PART, but we don't | |
118 | need to know this anymore. | |
119 | reload_optional char, nonzero for an optional reload. | |
120 | Optional reloads are ignored unless the | |
121 | value is already sitting in a register. | |
122 | reload_inc int, positive amount to increment or decrement by if | |
123 | reload_in is a PRE_DEC, PRE_INC, POST_DEC, POST_INC. | |
124 | Ignored otherwise (don't assume it is zero). | |
125 | reload_in_reg rtx. A reg for which reload_in is the equivalent. | |
126 | If reload_in is a symbol_ref which came from | |
127 | reg_equiv_constant, then this is the pseudo | |
128 | which has that symbol_ref as equivalent. | |
129 | reload_reg_rtx rtx. This is the register to reload into. | |
130 | If it is zero when `find_reloads' returns, | |
131 | you must find a suitable register in the class | |
132 | specified by reload_reg_class, and store here | |
133 | an rtx for that register with mode from | |
134 | reload_inmode or reload_outmode. | |
135 | reload_nocombine char, nonzero if this reload shouldn't be | |
136 | combined with another reload. | |
137 | reload_needed_for rtx, operand this reload is needed for address of. | |
138 | 0 means it isn't needed for addressing. | |
139 | reload_needed_for_multiple | |
140 | int, 1 if this reload needed for more than one thing. | |
141 | reload_when_needed enum, classifies reload as needed either for | |
142 | addressing an input reload, addressing an output, | |
143 | for addressing a non-reloaded mem ref, | |
144 | or for unspecified purposes (i.e., more than one | |
145 | of the above). | |
146 | reload_secondary_reload int, gives the reload number of a secondary | |
147 | reload, when needed; otherwise -1 | |
148 | reload_secondary_p int, 1 if this is a secondary register for one | |
149 | or more reloads. | |
150 | reload_secondary_icode enum insn_code, if a secondary reload is required, | |
151 | gives the INSN_CODE that uses the secondary | |
152 | reload as a scratch register, or CODE_FOR_nothing | |
153 | if the secondary reload register is to be an | |
154 | intermediate register. */ | |
155 | int n_reloads; | |
156 | ||
157 | rtx reload_in[MAX_RELOADS]; | |
158 | rtx reload_out[MAX_RELOADS]; | |
159 | enum reg_class reload_reg_class[MAX_RELOADS]; | |
160 | enum machine_mode reload_inmode[MAX_RELOADS]; | |
161 | enum machine_mode reload_outmode[MAX_RELOADS]; | |
162 | char reload_strict_low[MAX_RELOADS]; | |
163 | rtx reload_reg_rtx[MAX_RELOADS]; | |
164 | char reload_optional[MAX_RELOADS]; | |
165 | int reload_inc[MAX_RELOADS]; | |
166 | rtx reload_in_reg[MAX_RELOADS]; | |
167 | char reload_nocombine[MAX_RELOADS]; | |
168 | int reload_needed_for_multiple[MAX_RELOADS]; | |
169 | rtx reload_needed_for[MAX_RELOADS]; | |
170 | enum reload_when_needed reload_when_needed[MAX_RELOADS]; | |
171 | int reload_secondary_reload[MAX_RELOADS]; | |
172 | int reload_secondary_p[MAX_RELOADS]; | |
173 | enum insn_code reload_secondary_icode[MAX_RELOADS]; | |
174 | ||
175 | /* All the "earlyclobber" operands of the current insn | |
176 | are recorded here. */ | |
177 | int n_earlyclobbers; | |
178 | rtx reload_earlyclobbers[MAX_RECOG_OPERANDS]; | |
179 | ||
180 | /* Replacing reloads. | |
181 | ||
182 | If `replace_reloads' is nonzero, then as each reload is recorded | |
183 | an entry is made for it in the table `replacements'. | |
184 | Then later `subst_reloads' can look through that table and | |
185 | perform all the replacements needed. */ | |
186 | ||
187 | /* Nonzero means record the places to replace. */ | |
188 | static int replace_reloads; | |
189 | ||
190 | /* Each replacement is recorded with a structure like this. */ | |
191 | struct replacement | |
192 | { | |
193 | rtx *where; /* Location to store in */ | |
194 | rtx *subreg_loc; /* Location of SUBREG if WHERE is inside | |
195 | a SUBREG; 0 otherwise. */ | |
196 | int what; /* which reload this is for */ | |
197 | enum machine_mode mode; /* mode it must have */ | |
198 | }; | |
199 | ||
200 | static struct replacement replacements[MAX_RECOG_OPERANDS * ((MAX_REGS_PER_ADDRESS * 2) + 1)]; | |
201 | ||
202 | /* Number of replacements currently recorded. */ | |
203 | static int n_replacements; | |
204 | ||
205 | /* MEM-rtx's created for pseudo-regs in stack slots not directly addressable; | |
206 | (see reg_equiv_address). */ | |
207 | static rtx memlocs[MAX_RECOG_OPERANDS * ((MAX_REGS_PER_ADDRESS * 2) + 1)]; | |
208 | static int n_memlocs; | |
209 | ||
210 | /* The instruction we are doing reloads for; | |
211 | so we can test whether a register dies in it. */ | |
212 | static rtx this_insn; | |
213 | ||
214 | /* Nonzero if this instruction is a user-specified asm with operands. */ | |
215 | static int this_insn_is_asm; | |
216 | ||
217 | /* If hard_regs_live_known is nonzero, | |
218 | we can tell which hard regs are currently live, | |
219 | at least enough to succeed in choosing dummy reloads. */ | |
220 | static int hard_regs_live_known; | |
221 | ||
222 | /* Indexed by hard reg number, | |
223 | element is nonegative if hard reg has been spilled. | |
224 | This vector is passed to `find_reloads' as an argument | |
225 | and is not changed here. */ | |
226 | static short *static_reload_reg_p; | |
227 | ||
228 | /* Set to 1 in subst_reg_equivs if it changes anything. */ | |
229 | static int subst_reg_equivs_changed; | |
230 | ||
231 | /* On return from push_reload, holds the reload-number for the OUT | |
232 | operand, which can be different for that from the input operand. */ | |
233 | static int output_reloadnum; | |
234 | ||
235 | static int alternative_allows_memconst (); | |
236 | static rtx find_dummy_reload (); | |
237 | static rtx find_reloads_toplev (); | |
238 | static int find_reloads_address (); | |
239 | static int find_reloads_address_1 (); | |
240 | static void find_reloads_address_part (); | |
241 | static int hard_reg_set_here_p (); | |
242 | /* static rtx forget_volatility (); */ | |
243 | static rtx subst_reg_equivs (); | |
244 | static rtx subst_indexed_address (); | |
245 | rtx find_equiv_reg (); | |
246 | static int find_inc_amount (); | |
247 | \f | |
248 | #ifdef HAVE_SECONDARY_RELOADS | |
249 | ||
250 | /* Determine if any secondary reloads are needed for loading (if IN_P is | |
251 | non-zero) or storing (if IN_P is zero) X to or from a reload register of | |
252 | register class RELOAD_CLASS in mode RELOAD_MODE. | |
253 | ||
254 | Return the register class of a secondary reload register, or NO_REGS if | |
255 | none. *PMODE is set to the mode that the register is required in. | |
256 | If the reload register is needed as a scratch register instead of an | |
257 | intermediate register, *PICODE is set to the insn_code of the insn to be | |
258 | used to load or store the primary reload register; otherwise *PICODE | |
259 | is set to CODE_FOR_nothing. | |
260 | ||
261 | In some cases (such as storing MQ into an external memory location on | |
262 | the RT), both an intermediate register and a scratch register. In that | |
263 | case, *PICODE is set to CODE_FOR_nothing, the class for the intermediate | |
264 | register is returned, and the *PTERTIARY_... variables are set to describe | |
265 | the scratch register. */ | |
266 | ||
267 | static enum reg_class | |
268 | find_secondary_reload (x, reload_class, reload_mode, in_p, picode, pmode, | |
269 | ptertiary_class, ptertiary_icode, ptertiary_mode) | |
270 | rtx x; | |
271 | enum reg_class reload_class; | |
272 | enum machine_mode reload_mode; | |
273 | int in_p; | |
274 | enum insn_code *picode; | |
275 | enum machine_mode *pmode; | |
276 | enum reg_class *ptertiary_class; | |
277 | enum insn_code *ptertiary_icode; | |
278 | enum machine_mode *ptertiary_mode; | |
279 | { | |
280 | enum reg_class class = NO_REGS; | |
281 | enum machine_mode mode = reload_mode; | |
282 | enum insn_code icode = CODE_FOR_nothing; | |
283 | enum reg_class t_class = NO_REGS; | |
284 | enum machine_mode t_mode = VOIDmode; | |
285 | enum insn_code t_icode = CODE_FOR_nothing; | |
286 | ||
d45cf215 RS |
287 | /* If X is a pseudo-register that has an equivalent MEM (actually, if it |
288 | is still a pseudo-register by now, it *must* have an equivalent MEM | |
289 | but we don't want to assume that), use that equivalent when seeing if | |
290 | a secondary reload is needed since whether or not a reload is needed | |
291 | might be sensitive to the form of the MEM. */ | |
292 | ||
293 | if (GET_CODE (x) == REG && REGNO (x) >= FIRST_PSEUDO_REGISTER | |
294 | && reg_equiv_mem[REGNO (x)] != 0) | |
295 | x = reg_equiv_mem[REGNO (x)]; | |
296 | ||
eab89b90 RK |
297 | #ifdef SECONDARY_INPUT_RELOAD_CLASS |
298 | if (in_p) | |
299 | class = SECONDARY_INPUT_RELOAD_CLASS (reload_class, reload_mode, x); | |
300 | #endif | |
301 | ||
302 | #ifdef SECONDARY_OUTPUT_RELOAD_CLASS | |
303 | if (! in_p) | |
304 | class = SECONDARY_OUTPUT_RELOAD_CLASS (reload_class, reload_mode, x); | |
305 | #endif | |
306 | ||
307 | /* If we don't need any secondary registers, go away; the rest of the | |
308 | values won't be used. */ | |
309 | if (class == NO_REGS) | |
310 | return NO_REGS; | |
311 | ||
312 | /* Get a possible insn to use. If the predicate doesn't accept X, don't | |
313 | use the insn. */ | |
314 | ||
315 | icode = (in_p ? reload_in_optab[(int) reload_mode] | |
316 | : reload_out_optab[(int) reload_mode]); | |
317 | ||
318 | if (icode != CODE_FOR_nothing | |
319 | && insn_operand_predicate[(int) icode][in_p] | |
320 | && (! (insn_operand_predicate[(int) icode][in_p]) (x, reload_mode))) | |
321 | icode = CODE_FOR_nothing; | |
322 | ||
323 | /* If we will be using an insn, see if it can directly handle the reload | |
324 | register we will be using. If it can, the secondary reload is for a | |
325 | scratch register. If it can't, we will use the secondary reload for | |
326 | an intermediate register and require a tertiary reload for the scratch | |
327 | register. */ | |
328 | ||
329 | if (icode != CODE_FOR_nothing) | |
330 | { | |
331 | /* If IN_P is non-zero, the reload register will be the output in | |
332 | operand 0. If IN_P is zero, the reload register will be the input | |
333 | in operand 1. Outputs should have an initial "=", which we must | |
334 | skip. */ | |
335 | ||
d45cf215 | 336 | char insn_letter = insn_operand_constraint[(int) icode][!in_p][in_p]; |
eab89b90 | 337 | enum reg_class insn_class |
d45cf215 RS |
338 | = (insn_letter == 'r' ? GENERAL_REGS |
339 | : REG_CLASS_FROM_LETTER (insn_letter)); | |
eab89b90 RK |
340 | |
341 | if (insn_class == NO_REGS | |
342 | || (in_p && insn_operand_constraint[(int) icode][!in_p][0] != '=') | |
343 | /* The scratch register's constraint must start with "=&". */ | |
344 | || insn_operand_constraint[(int) icode][2][0] != '=' | |
345 | || insn_operand_constraint[(int) icode][2][1] != '&') | |
346 | abort (); | |
347 | ||
348 | if (reg_class_subset_p (reload_class, insn_class)) | |
349 | mode = insn_operand_mode[(int) icode][2]; | |
350 | else | |
351 | { | |
d45cf215 | 352 | char t_letter = insn_operand_constraint[(int) icode][2][2]; |
eab89b90 RK |
353 | class = insn_class; |
354 | t_mode = insn_operand_mode[(int) icode][2]; | |
d45cf215 RS |
355 | t_class = (t_letter == 'r' ? GENERAL_REGS |
356 | : REG_CLASS_FROM_LETTER (t_letter)); | |
eab89b90 RK |
357 | t_icode = icode; |
358 | icode = CODE_FOR_nothing; | |
359 | } | |
360 | } | |
361 | ||
362 | *pmode = mode; | |
363 | *picode = icode; | |
364 | *ptertiary_class = t_class; | |
365 | *ptertiary_mode = t_mode; | |
366 | *ptertiary_icode = t_icode; | |
367 | ||
368 | return class; | |
369 | } | |
370 | #endif /* HAVE_SECONDARY_RELOADS */ | |
371 | \f | |
372 | /* Record one (sometimes two) reload that needs to be performed. | |
373 | IN is an rtx saying where the data are to be found before this instruction. | |
374 | OUT says where they must be stored after the instruction. | |
375 | (IN is zero for data not read, and OUT is zero for data not written.) | |
376 | INLOC and OUTLOC point to the places in the instructions where | |
377 | IN and OUT were found. | |
378 | CLASS is a register class required for the reloaded data. | |
379 | INMODE is the machine mode that the instruction requires | |
380 | for the reg that replaces IN and OUTMODE is likewise for OUT. | |
381 | ||
382 | If IN is zero, then OUT's location and mode should be passed as | |
383 | INLOC and INMODE. | |
384 | ||
385 | STRICT_LOW is the 1 if there is a containing STRICT_LOW_PART rtx. | |
386 | ||
387 | OPTIONAL nonzero means this reload does not need to be performed: | |
388 | it can be discarded if that is more convenient. | |
389 | ||
390 | The return value is the reload-number for this reload. | |
391 | ||
392 | If both IN and OUT are nonzero, in some rare cases we might | |
393 | want to make two separate reloads. (Actually we never do this now.) | |
394 | Therefore, the reload-number for OUT is stored in | |
395 | output_reloadnum when we return; the return value applies to IN. | |
396 | Usually (presently always), when IN and OUT are nonzero, | |
397 | the two reload-numbers are equal, but the caller should be careful to | |
398 | distinguish them. */ | |
399 | ||
400 | static int | |
401 | push_reload (in, out, inloc, outloc, class, | |
402 | inmode, outmode, strict_low, optional, needed_for) | |
403 | register rtx in, out; | |
404 | rtx *inloc, *outloc; | |
405 | enum reg_class class; | |
406 | enum machine_mode inmode, outmode; | |
407 | int strict_low; | |
408 | int optional; | |
409 | rtx needed_for; | |
410 | { | |
411 | register int i; | |
412 | int dont_share = 0; | |
413 | rtx *in_subreg_loc = 0, *out_subreg_loc = 0; | |
414 | int secondary_reload = -1; | |
415 | enum insn_code secondary_icode = CODE_FOR_nothing; | |
416 | ||
417 | /* Compare two RTX's. */ | |
418 | #define MATCHES(x, y) \ | |
419 | (x == y || (x != 0 && (GET_CODE (x) == REG \ | |
420 | ? GET_CODE (y) == REG && REGNO (x) == REGNO (y) \ | |
421 | : rtx_equal_p (x, y) && ! side_effects_p (x)))) | |
422 | ||
423 | /* INMODE and/or OUTMODE could be VOIDmode if no mode | |
424 | has been specified for the operand. In that case, | |
425 | use the operand's mode as the mode to reload. */ | |
426 | if (inmode == VOIDmode && in != 0) | |
427 | inmode = GET_MODE (in); | |
428 | if (outmode == VOIDmode && out != 0) | |
429 | outmode = GET_MODE (out); | |
430 | ||
431 | /* If IN is a pseudo register everywhere-equivalent to a constant, and | |
432 | it is not in a hard register, reload straight from the constant, | |
433 | since we want to get rid of such pseudo registers. | |
434 | Often this is done earlier, but not always in find_reloads_address. */ | |
435 | if (in != 0 && GET_CODE (in) == REG) | |
436 | { | |
437 | register int regno = REGNO (in); | |
438 | ||
439 | if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 | |
440 | && reg_equiv_constant[regno] != 0) | |
441 | in = reg_equiv_constant[regno]; | |
442 | } | |
443 | ||
444 | /* Likewise for OUT. Of course, OUT will never be equivalent to | |
445 | an actual constant, but it might be equivalent to a memory location | |
446 | (in the case of a parameter). */ | |
447 | if (out != 0 && GET_CODE (out) == REG) | |
448 | { | |
449 | register int regno = REGNO (out); | |
450 | ||
451 | if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 | |
452 | && reg_equiv_constant[regno] != 0) | |
453 | out = reg_equiv_constant[regno]; | |
454 | } | |
455 | ||
456 | /* If we have a read-write operand with an address side-effect, | |
457 | change either IN or OUT so the side-effect happens only once. */ | |
458 | if (in != 0 && out != 0 && GET_CODE (in) == MEM && rtx_equal_p (in, out)) | |
459 | { | |
460 | if (GET_CODE (XEXP (in, 0)) == POST_INC | |
461 | || GET_CODE (XEXP (in, 0)) == POST_DEC) | |
462 | in = gen_rtx (MEM, GET_MODE (in), XEXP (XEXP (in, 0), 0)); | |
463 | if (GET_CODE (XEXP (in, 0)) == PRE_INC | |
464 | || GET_CODE (XEXP (in, 0)) == PRE_DEC) | |
465 | out = gen_rtx (MEM, GET_MODE (out), XEXP (XEXP (out, 0), 0)); | |
466 | } | |
467 | ||
468 | /* If we are reloading a (SUBREG (MEM ...) ...) or (SUBREG constant ...), | |
469 | really reload just the inside expression in its own mode. | |
470 | If we have (SUBREG:M1 (REG:M2 ...) ...) with M1 wider than M2 and the | |
471 | register is a pseudo, this will become the same as the above case. | |
472 | Do the same for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where | |
473 | either M1 is not valid for R or M2 is wider than a word but we only | |
474 | need one word to store an M2-sized quantity in R. | |
475 | Note that the case of (SUBREG (CONST_INT...)...) is handled elsewhere; | |
476 | we can't handle it here because CONST_INT does not indicate a mode. | |
477 | ||
478 | Similarly, we must reload the inside expression if we have a | |
479 | STRICT_LOW_PART (presumably, in == out in the cas). */ | |
480 | ||
481 | if (in != 0 && GET_CODE (in) == SUBREG | |
482 | && (GET_CODE (SUBREG_REG (in)) != REG | |
483 | || strict_low | |
484 | || (GET_CODE (SUBREG_REG (in)) == REG | |
485 | && REGNO (SUBREG_REG (in)) >= FIRST_PSEUDO_REGISTER | |
486 | && (GET_MODE_SIZE (inmode) | |
487 | > GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))))) | |
488 | || (GET_CODE (SUBREG_REG (in)) == REG | |
489 | && REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER | |
490 | && (! HARD_REGNO_MODE_OK (REGNO (SUBREG_REG (in)), inmode) | |
491 | || (GET_MODE_SIZE (inmode) <= UNITS_PER_WORD | |
492 | && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) | |
493 | > UNITS_PER_WORD) | |
494 | && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) | |
495 | / UNITS_PER_WORD) | |
496 | != HARD_REGNO_NREGS (REGNO (SUBREG_REG (in)), | |
497 | GET_MODE (SUBREG_REG (in))))))))) | |
498 | { | |
499 | in_subreg_loc = inloc; | |
500 | inloc = &SUBREG_REG (in); | |
501 | in = *inloc; | |
502 | if (GET_CODE (in) == MEM) | |
503 | /* This is supposed to happen only for paradoxical subregs made by | |
504 | combine.c. (SUBREG (MEM)) isn't supposed to occur other ways. */ | |
505 | if (GET_MODE_SIZE (GET_MODE (in)) > GET_MODE_SIZE (inmode)) | |
506 | abort (); | |
507 | inmode = GET_MODE (in); | |
508 | } | |
509 | ||
510 | /* Similarly for paradoxical and problematical SUBREGs on the output. | |
511 | Note that there is no reason we need worry about the previous value | |
512 | of SUBREG_REG (out); even if wider than out, | |
513 | storing in a subreg is entitled to clobber it all | |
514 | (except in the case of STRICT_LOW_PART, | |
515 | and in that case the constraint should label it input-output.) */ | |
516 | if (out != 0 && GET_CODE (out) == SUBREG | |
517 | && (GET_CODE (SUBREG_REG (out)) != REG | |
518 | || strict_low | |
519 | || (GET_CODE (SUBREG_REG (out)) == REG | |
520 | && REGNO (SUBREG_REG (out)) >= FIRST_PSEUDO_REGISTER | |
521 | && (GET_MODE_SIZE (outmode) | |
522 | > GET_MODE_SIZE (GET_MODE (SUBREG_REG (out))))) | |
523 | || (GET_CODE (SUBREG_REG (out)) == REG | |
524 | && REGNO (SUBREG_REG (out)) < FIRST_PSEUDO_REGISTER | |
525 | && (! HARD_REGNO_MODE_OK (REGNO (SUBREG_REG (out)), outmode) | |
526 | || (GET_MODE_SIZE (outmode) <= UNITS_PER_WORD | |
527 | && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (out))) | |
528 | > UNITS_PER_WORD) | |
529 | && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (out))) | |
530 | / UNITS_PER_WORD) | |
531 | != HARD_REGNO_NREGS (REGNO (SUBREG_REG (out)), | |
532 | GET_MODE (SUBREG_REG (out))))))))) | |
533 | { | |
534 | out_subreg_loc = outloc; | |
535 | outloc = &SUBREG_REG (out); | |
536 | out = *outloc; | |
537 | if (GET_CODE (out) == MEM | |
538 | && GET_MODE_SIZE (GET_MODE (out)) > GET_MODE_SIZE (outmode)) | |
539 | abort (); | |
540 | outmode = GET_MODE (out); | |
541 | } | |
542 | ||
543 | /* That's all we use STRICT_LOW for, so clear it. At some point, | |
544 | we may want to get rid of reload_strict_low. */ | |
545 | strict_low = 0; | |
546 | ||
547 | /* If IN appears in OUT, we can't share any input-only reload for IN. */ | |
548 | if (in != 0 && out != 0 && GET_CODE (out) == MEM | |
549 | && (GET_CODE (in) == REG || GET_CODE (in) == MEM) | |
550 | && reg_overlap_mentioned_p (in, XEXP (out, 0))) | |
551 | dont_share = 1; | |
552 | ||
553 | /* Narrow down the class of register wanted if that is | |
554 | desirable on this machine for efficiency. */ | |
555 | if (in != 0) | |
556 | class = PREFERRED_RELOAD_CLASS (in, class); | |
557 | ||
558 | /* Make sure we use a class that can handle the actual pseudo | |
559 | inside any subreg. For example, on the 386, QImode regs | |
560 | can appear within SImode subregs. Although GENERAL_REGS | |
561 | can handle SImode, QImode needs a smaller class. */ | |
562 | #ifdef LIMIT_RELOAD_CLASS | |
563 | if (in_subreg_loc) | |
564 | class = LIMIT_RELOAD_CLASS (inmode, class); | |
565 | else if (in != 0 && GET_CODE (in) == SUBREG) | |
566 | class = LIMIT_RELOAD_CLASS (GET_MODE (SUBREG_REG (in)), class); | |
567 | ||
568 | if (out_subreg_loc) | |
569 | class = LIMIT_RELOAD_CLASS (outmode, class); | |
570 | if (out != 0 && GET_CODE (out) == SUBREG) | |
571 | class = LIMIT_RELOAD_CLASS (GET_MODE (SUBREG_REG (out)), class); | |
572 | #endif | |
573 | ||
574 | if (class == NO_REGS) | |
575 | abort (); | |
576 | ||
577 | /* Verify that this class is at least possible for the mode that | |
578 | is specified. */ | |
579 | if (this_insn_is_asm) | |
580 | { | |
581 | enum machine_mode mode; | |
582 | if (GET_MODE_SIZE (inmode) > GET_MODE_SIZE (outmode)) | |
583 | mode = inmode; | |
584 | else | |
585 | mode = outmode; | |
586 | for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) | |
587 | if (HARD_REGNO_MODE_OK (i, mode) | |
588 | && TEST_HARD_REG_BIT (reg_class_contents[(int) class], i)) | |
589 | { | |
590 | int nregs = HARD_REGNO_NREGS (i, mode); | |
591 | ||
592 | int j; | |
593 | for (j = 1; j < nregs; j++) | |
594 | if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class], i + j)) | |
595 | break; | |
596 | if (j == nregs) | |
597 | break; | |
598 | } | |
599 | if (i == FIRST_PSEUDO_REGISTER) | |
600 | { | |
601 | error_for_asm (this_insn, "impossible register constraint in `asm'"); | |
602 | class = ALL_REGS; | |
603 | } | |
604 | } | |
605 | ||
606 | /* We can use an existing reload if the class is right | |
607 | and at least one of IN and OUT is a match | |
608 | and the other is at worst neutral. | |
609 | (A zero compared against anything is neutral.) */ | |
610 | for (i = 0; i < n_reloads; i++) | |
611 | if ((reg_class_subset_p (class, reload_reg_class[i]) | |
612 | || reg_class_subset_p (reload_reg_class[i], class)) | |
613 | && reload_strict_low[i] == strict_low | |
614 | /* If the existing reload has a register, it must fit our class. */ | |
615 | && (reload_reg_rtx[i] == 0 | |
616 | || TEST_HARD_REG_BIT (reg_class_contents[(int) class], | |
617 | true_regnum (reload_reg_rtx[i]))) | |
618 | && ((in != 0 && MATCHES (reload_in[i], in) && ! dont_share | |
619 | && (out == 0 || reload_out[i] == 0 || MATCHES (reload_out[i], out))) | |
620 | || | |
621 | (out != 0 && MATCHES (reload_out[i], out) | |
622 | && (in == 0 || reload_in[i] == 0 || MATCHES (reload_in[i], in))))) | |
623 | break; | |
624 | ||
625 | /* Reloading a plain reg for input can match a reload to postincrement | |
626 | that reg, since the postincrement's value is the right value. | |
627 | Likewise, it can match a preincrement reload, since we regard | |
628 | the preincrementation as happening before any ref in this insn | |
629 | to that register. */ | |
630 | if (i == n_reloads) | |
631 | for (i = 0; i < n_reloads; i++) | |
632 | if ((reg_class_subset_p (class, reload_reg_class[i]) | |
633 | || reg_class_subset_p (reload_reg_class[i], class)) | |
634 | /* If the existing reload has a register, it must fit our class. */ | |
635 | && (reload_reg_rtx[i] == 0 | |
636 | || TEST_HARD_REG_BIT (reg_class_contents[(int) class], | |
637 | true_regnum (reload_reg_rtx[i]))) | |
638 | && reload_strict_low[i] == strict_low | |
639 | && out == 0 && reload_out[i] == 0 && reload_in[i] != 0 | |
640 | && ((GET_CODE (in) == REG | |
641 | && (GET_CODE (reload_in[i]) == POST_INC | |
642 | || GET_CODE (reload_in[i]) == POST_DEC | |
643 | || GET_CODE (reload_in[i]) == PRE_INC | |
644 | || GET_CODE (reload_in[i]) == PRE_DEC) | |
645 | && MATCHES (XEXP (reload_in[i], 0), in)) | |
646 | || | |
647 | (GET_CODE (reload_in[i]) == REG | |
648 | && (GET_CODE (in) == POST_INC | |
649 | || GET_CODE (in) == POST_DEC | |
650 | || GET_CODE (in) == PRE_INC | |
651 | || GET_CODE (in) == PRE_DEC) | |
652 | && MATCHES (XEXP (in, 0), reload_in[i])))) | |
653 | { | |
654 | /* Make sure reload_in ultimately has the increment, | |
655 | not the plain register. */ | |
656 | if (GET_CODE (in) == REG) | |
657 | in = reload_in[i]; | |
658 | break; | |
659 | } | |
660 | ||
661 | if (i == n_reloads) | |
662 | { | |
663 | #ifdef HAVE_SECONDARY_RELOADS | |
664 | enum reg_class secondary_class = NO_REGS; | |
665 | enum reg_class secondary_out_class = NO_REGS; | |
666 | enum machine_mode secondary_mode = inmode; | |
667 | enum machine_mode secondary_out_mode = outmode; | |
668 | enum insn_code secondary_icode; | |
669 | enum insn_code secondary_out_icode = CODE_FOR_nothing; | |
670 | enum reg_class tertiary_class = NO_REGS; | |
671 | enum reg_class tertiary_out_class = NO_REGS; | |
672 | enum machine_mode tertiary_mode; | |
673 | enum machine_mode tertiary_out_mode; | |
674 | enum insn_code tertiary_icode; | |
675 | enum insn_code tertiary_out_icode = CODE_FOR_nothing; | |
676 | int tertiary_reload = -1; | |
677 | ||
678 | /* See if we need a secondary reload register to move between | |
679 | CLASS and IN or CLASS and OUT. Get the modes and icodes to | |
680 | use for each of them if so. */ | |
681 | ||
682 | #ifdef SECONDARY_INPUT_RELOAD_CLASS | |
683 | if (in != 0) | |
684 | secondary_class | |
685 | = find_secondary_reload (in, class, inmode, 1, &secondary_icode, | |
686 | &secondary_mode, &tertiary_class, | |
687 | &tertiary_icode, &tertiary_mode); | |
688 | #endif | |
689 | ||
690 | #ifdef SECONDARY_OUTPUT_RELOAD_CLASS | |
691 | if (out != 0 && GET_CODE (out) != SCRATCH) | |
692 | secondary_out_class | |
693 | = find_secondary_reload (out, class, outmode, 0, | |
694 | &secondary_out_icode, &secondary_out_mode, | |
695 | &tertiary_out_class, &tertiary_out_icode, | |
696 | &tertiary_out_mode); | |
697 | #endif | |
698 | ||
699 | /* We can only record one secondary and one tertiary reload. If both | |
700 | IN and OUT need secondary reloads, we can only make an in-out | |
701 | reload if neither need an insn and if the classes are compatible. */ | |
702 | ||
703 | if (secondary_class != NO_REGS && secondary_out_class != NO_REGS | |
704 | && reg_class_subset_p (secondary_out_class, secondary_class)) | |
705 | secondary_class = secondary_out_class; | |
706 | ||
707 | if (secondary_class != NO_REGS && secondary_out_class != NO_REGS | |
708 | && (! reg_class_subset_p (secondary_class, secondary_out_class) | |
709 | || secondary_icode != CODE_FOR_nothing | |
710 | || secondary_out_icode != CODE_FOR_nothing)) | |
711 | { | |
712 | push_reload (0, out, 0, outloc, class, VOIDmode, outmode, | |
713 | strict_low, optional, needed_for); | |
714 | out = 0; | |
715 | outloc = 0; | |
716 | outmode = VOIDmode; | |
717 | } | |
718 | ||
719 | /* If we need a secondary reload for OUT but not IN, copy the | |
720 | information. */ | |
721 | if (secondary_class == NO_REGS && secondary_out_class != NO_REGS) | |
722 | { | |
723 | secondary_class = secondary_out_class; | |
724 | secondary_icode = secondary_out_icode; | |
725 | tertiary_class = tertiary_out_class; | |
726 | tertiary_icode = tertiary_out_icode; | |
727 | tertiary_mode = tertiary_out_mode; | |
728 | } | |
729 | ||
730 | if (secondary_class != NO_REGS) | |
731 | { | |
732 | /* If we need a tertiary reload, see if we have one we can reuse | |
733 | or else make one. */ | |
734 | ||
735 | if (tertiary_class != NO_REGS) | |
736 | { | |
737 | for (tertiary_reload = 0; tertiary_reload < n_reloads; | |
738 | tertiary_reload++) | |
739 | if (reload_secondary_p[tertiary_reload] | |
740 | && (reg_class_subset_p (tertiary_class, | |
741 | reload_reg_class[tertiary_reload]) | |
742 | || reg_class_subset_p (reload_reg_class[tertiary_reload], | |
743 | tertiary_class)) | |
744 | && ((reload_inmode[tertiary_reload] == tertiary_mode) | |
745 | || reload_inmode[tertiary_reload] == VOIDmode) | |
746 | && ((reload_outmode[tertiary_reload] == tertiary_mode) | |
747 | || reload_outmode[tertiary_reload] == VOIDmode) | |
748 | && (reload_secondary_icode[tertiary_reload] | |
749 | == CODE_FOR_nothing)) | |
750 | ||
751 | { | |
752 | if (tertiary_mode != VOIDmode) | |
753 | reload_inmode[tertiary_reload] = tertiary_mode; | |
754 | if (tertiary_out_mode != VOIDmode) | |
755 | reload_outmode[tertiary_reload] = tertiary_mode; | |
756 | if (reg_class_subset_p (tertiary_class, | |
757 | reload_reg_class[tertiary_reload])) | |
758 | reload_reg_class[tertiary_reload] = tertiary_class; | |
759 | if (reload_needed_for[tertiary_reload] != needed_for) | |
760 | reload_needed_for_multiple[tertiary_reload] = 1; | |
761 | reload_optional[tertiary_reload] &= optional; | |
762 | reload_secondary_p[tertiary_reload] = 1; | |
763 | } | |
764 | ||
765 | if (tertiary_reload == n_reloads) | |
766 | { | |
767 | /* We need to make a new tertiary reload for this register | |
768 | class. */ | |
769 | reload_in[tertiary_reload] = reload_out[tertiary_reload] = 0; | |
770 | reload_reg_class[tertiary_reload] = tertiary_class; | |
771 | reload_inmode[tertiary_reload] = tertiary_mode; | |
772 | reload_outmode[tertiary_reload] = tertiary_mode; | |
773 | reload_reg_rtx[tertiary_reload] = 0; | |
774 | reload_optional[tertiary_reload] = optional; | |
775 | reload_inc[tertiary_reload] = 0; | |
776 | reload_strict_low[tertiary_reload] = 0; | |
777 | /* Maybe we could combine these, but it seems too tricky. */ | |
778 | reload_nocombine[tertiary_reload] = 1; | |
779 | reload_in_reg[tertiary_reload] = 0; | |
780 | reload_needed_for[tertiary_reload] = needed_for; | |
781 | reload_needed_for_multiple[tertiary_reload] = 0; | |
782 | reload_secondary_reload[tertiary_reload] = -1; | |
783 | reload_secondary_icode[tertiary_reload] = CODE_FOR_nothing; | |
784 | reload_secondary_p[tertiary_reload] = 1; | |
785 | ||
786 | n_reloads++; | |
787 | i = n_reloads; | |
788 | } | |
789 | } | |
790 | ||
791 | /* See if we can reuse an existing secondary reload. */ | |
792 | for (secondary_reload = 0; secondary_reload < n_reloads; | |
793 | secondary_reload++) | |
794 | if (reload_secondary_p[secondary_reload] | |
795 | && (reg_class_subset_p (secondary_class, | |
796 | reload_reg_class[secondary_reload]) | |
797 | || reg_class_subset_p (reload_reg_class[secondary_reload], | |
798 | secondary_class)) | |
799 | && ((reload_inmode[secondary_reload] == secondary_mode) | |
800 | || reload_inmode[secondary_reload] == VOIDmode) | |
801 | && ((reload_outmode[secondary_reload] == secondary_out_mode) | |
802 | || reload_outmode[secondary_reload] == VOIDmode) | |
803 | && reload_secondary_reload[secondary_reload] == tertiary_reload | |
804 | && reload_secondary_icode[secondary_reload] == tertiary_icode) | |
805 | { | |
806 | if (secondary_mode != VOIDmode) | |
807 | reload_inmode[secondary_reload] = secondary_mode; | |
808 | if (secondary_out_mode != VOIDmode) | |
809 | reload_outmode[secondary_reload] = secondary_out_mode; | |
810 | if (reg_class_subset_p (secondary_class, | |
811 | reload_reg_class[secondary_reload])) | |
812 | reload_reg_class[secondary_reload] = secondary_class; | |
813 | if (reload_needed_for[secondary_reload] != needed_for) | |
814 | reload_needed_for_multiple[secondary_reload] = 1; | |
815 | reload_optional[secondary_reload] &= optional; | |
816 | reload_secondary_p[secondary_reload] = 1; | |
817 | } | |
818 | ||
819 | if (secondary_reload == n_reloads) | |
820 | { | |
821 | /* We need to make a new secondary reload for this register | |
822 | class. */ | |
823 | reload_in[secondary_reload] = reload_out[secondary_reload] = 0; | |
824 | reload_reg_class[secondary_reload] = secondary_class; | |
825 | reload_inmode[secondary_reload] = secondary_mode; | |
826 | reload_outmode[secondary_reload] = secondary_out_mode; | |
827 | reload_reg_rtx[secondary_reload] = 0; | |
828 | reload_optional[secondary_reload] = optional; | |
829 | reload_inc[secondary_reload] = 0; | |
830 | reload_strict_low[secondary_reload] = 0; | |
831 | /* Maybe we could combine these, but it seems too tricky. */ | |
832 | reload_nocombine[secondary_reload] = 1; | |
833 | reload_in_reg[secondary_reload] = 0; | |
834 | reload_needed_for[secondary_reload] = needed_for; | |
835 | reload_needed_for_multiple[secondary_reload] = 0; | |
836 | reload_secondary_reload[secondary_reload] = tertiary_reload; | |
837 | reload_secondary_icode[secondary_reload] = tertiary_icode; | |
838 | reload_secondary_p[secondary_reload] = 1; | |
839 | ||
840 | n_reloads++; | |
841 | i = n_reloads; | |
842 | } | |
843 | } | |
844 | #endif | |
845 | ||
846 | /* We found no existing reload suitable for re-use. | |
847 | So add an additional reload. */ | |
848 | ||
849 | reload_in[i] = in; | |
850 | reload_out[i] = out; | |
851 | reload_reg_class[i] = class; | |
852 | reload_inmode[i] = inmode; | |
853 | reload_outmode[i] = outmode; | |
854 | reload_reg_rtx[i] = 0; | |
855 | reload_optional[i] = optional; | |
856 | reload_inc[i] = 0; | |
857 | reload_strict_low[i] = strict_low; | |
858 | reload_nocombine[i] = 0; | |
859 | reload_in_reg[i] = inloc ? *inloc : 0; | |
860 | reload_needed_for[i] = needed_for; | |
861 | reload_needed_for_multiple[i] = 0; | |
862 | reload_secondary_reload[i] = secondary_reload; | |
863 | reload_secondary_icode[i] = secondary_icode; | |
864 | reload_secondary_p[i] = 0; | |
865 | ||
866 | n_reloads++; | |
867 | } | |
868 | else | |
869 | { | |
870 | /* We are reusing an existing reload, | |
871 | but we may have additional information for it. | |
872 | For example, we may now have both IN and OUT | |
873 | while the old one may have just one of them. */ | |
874 | ||
875 | if (inmode != VOIDmode) | |
876 | reload_inmode[i] = inmode; | |
877 | if (outmode != VOIDmode) | |
878 | reload_outmode[i] = outmode; | |
879 | if (in != 0) | |
880 | reload_in[i] = in; | |
881 | if (out != 0) | |
882 | reload_out[i] = out; | |
883 | if (reg_class_subset_p (class, reload_reg_class[i])) | |
884 | reload_reg_class[i] = class; | |
885 | reload_optional[i] &= optional; | |
886 | if (reload_needed_for[i] != needed_for) | |
887 | reload_needed_for_multiple[i] = 1; | |
888 | } | |
889 | ||
890 | /* If the ostensible rtx being reload differs from the rtx found | |
891 | in the location to substitute, this reload is not safe to combine | |
892 | because we cannot reliably tell whether it appears in the insn. */ | |
893 | ||
894 | if (in != 0 && in != *inloc) | |
895 | reload_nocombine[i] = 1; | |
896 | ||
897 | #if 0 | |
898 | /* This was replaced by changes in find_reloads_address_1 and the new | |
899 | function inc_for_reload, which go with a new meaning of reload_inc. */ | |
900 | ||
901 | /* If this is an IN/OUT reload in an insn that sets the CC, | |
902 | it must be for an autoincrement. It doesn't work to store | |
903 | the incremented value after the insn because that would clobber the CC. | |
904 | So we must do the increment of the value reloaded from, | |
905 | increment it, store it back, then decrement again. */ | |
906 | if (out != 0 && sets_cc0_p (PATTERN (this_insn))) | |
907 | { | |
908 | out = 0; | |
909 | reload_out[i] = 0; | |
910 | reload_inc[i] = find_inc_amount (PATTERN (this_insn), in); | |
911 | /* If we did not find a nonzero amount-to-increment-by, | |
912 | that contradicts the belief that IN is being incremented | |
913 | in an address in this insn. */ | |
914 | if (reload_inc[i] == 0) | |
915 | abort (); | |
916 | } | |
917 | #endif | |
918 | ||
919 | /* If we will replace IN and OUT with the reload-reg, | |
920 | record where they are located so that substitution need | |
921 | not do a tree walk. */ | |
922 | ||
923 | if (replace_reloads) | |
924 | { | |
925 | if (inloc != 0) | |
926 | { | |
927 | register struct replacement *r = &replacements[n_replacements++]; | |
928 | r->what = i; | |
929 | r->subreg_loc = in_subreg_loc; | |
930 | r->where = inloc; | |
931 | r->mode = inmode; | |
932 | } | |
933 | if (outloc != 0 && outloc != inloc) | |
934 | { | |
935 | register struct replacement *r = &replacements[n_replacements++]; | |
936 | r->what = i; | |
937 | r->where = outloc; | |
938 | r->subreg_loc = out_subreg_loc; | |
939 | r->mode = outmode; | |
940 | } | |
941 | } | |
942 | ||
943 | /* If this reload is just being introduced and it has both | |
944 | an incoming quantity and an outgoing quantity that are | |
945 | supposed to be made to match, see if either one of the two | |
946 | can serve as the place to reload into. | |
947 | ||
948 | If one of them is acceptable, set reload_reg_rtx[i] | |
949 | to that one. */ | |
950 | ||
951 | if (in != 0 && out != 0 && in != out && reload_reg_rtx[i] == 0) | |
952 | { | |
953 | reload_reg_rtx[i] = find_dummy_reload (in, out, inloc, outloc, | |
954 | reload_reg_class[i], i); | |
955 | ||
956 | /* If the outgoing register already contains the same value | |
957 | as the incoming one, we can dispense with loading it. | |
958 | The easiest way to tell the caller that is to give a phony | |
959 | value for the incoming operand (same as outgoing one). */ | |
960 | if (reload_reg_rtx[i] == out | |
961 | && (GET_CODE (in) == REG || CONSTANT_P (in)) | |
962 | && 0 != find_equiv_reg (in, this_insn, 0, REGNO (out), | |
963 | static_reload_reg_p, i, inmode)) | |
964 | reload_in[i] = out; | |
965 | } | |
966 | ||
967 | /* If this is an input reload and the operand contains a register that | |
968 | dies in this insn and is used nowhere else, see if it is the right class | |
969 | to be used for this reload. Use it if so. (This occurs most commonly | |
970 | in the case of paradoxical SUBREGs and in-out reloads). We cannot do | |
971 | this if it is also an output reload that mentions the register unless | |
972 | the output is a SUBREG that clobbers an entire register. | |
973 | ||
974 | Note that the operand might be one of the spill regs, if it is a | |
975 | pseudo reg and we are in a block where spilling has not taken place. | |
976 | But if there is no spilling in this block, that is OK. | |
977 | An explicitly used hard reg cannot be a spill reg. */ | |
978 | ||
979 | if (reload_reg_rtx[i] == 0 && in != 0) | |
980 | { | |
981 | rtx note; | |
982 | int regno; | |
983 | ||
984 | for (note = REG_NOTES (this_insn); note; note = XEXP (note, 1)) | |
985 | if (REG_NOTE_KIND (note) == REG_DEAD | |
986 | && GET_CODE (XEXP (note, 0)) == REG | |
987 | && (regno = REGNO (XEXP (note, 0))) < FIRST_PSEUDO_REGISTER | |
988 | && reg_mentioned_p (XEXP (note, 0), in) | |
989 | && ! refers_to_regno_for_reload_p (regno, | |
990 | (regno | |
991 | + HARD_REGNO_NREGS (regno, | |
992 | inmode)), | |
993 | PATTERN (this_insn), inloc) | |
994 | && (in != out | |
995 | || (GET_CODE (in) == SUBREG | |
996 | && (((GET_MODE_SIZE (GET_MODE (in)) + (UNITS_PER_WORD - 1)) | |
997 | / UNITS_PER_WORD) | |
998 | == ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) | |
999 | + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)))) | |
1000 | /* Make sure the operand fits in the reg that dies. */ | |
1001 | && GET_MODE_SIZE (inmode) <= GET_MODE_SIZE (GET_MODE (XEXP (note, 0))) | |
1002 | && HARD_REGNO_MODE_OK (regno, inmode) | |
1003 | && GET_MODE_SIZE (outmode) <= GET_MODE_SIZE (GET_MODE (XEXP (note, 0))) | |
1004 | && HARD_REGNO_MODE_OK (regno, outmode) | |
1005 | && TEST_HARD_REG_BIT (reg_class_contents[(int) class], regno) | |
1006 | && !fixed_regs[regno]) | |
1007 | { | |
1008 | reload_reg_rtx[i] = gen_rtx (REG, inmode, regno); | |
1009 | break; | |
1010 | } | |
1011 | } | |
1012 | ||
1013 | if (out) | |
1014 | output_reloadnum = i; | |
1015 | ||
1016 | return i; | |
1017 | } | |
1018 | ||
1019 | /* Record an additional place we must replace a value | |
1020 | for which we have already recorded a reload. | |
1021 | RELOADNUM is the value returned by push_reload | |
1022 | when the reload was recorded. | |
1023 | This is used in insn patterns that use match_dup. */ | |
1024 | ||
1025 | static void | |
1026 | push_replacement (loc, reloadnum, mode) | |
1027 | rtx *loc; | |
1028 | int reloadnum; | |
1029 | enum machine_mode mode; | |
1030 | { | |
1031 | if (replace_reloads) | |
1032 | { | |
1033 | register struct replacement *r = &replacements[n_replacements++]; | |
1034 | r->what = reloadnum; | |
1035 | r->where = loc; | |
1036 | r->subreg_loc = 0; | |
1037 | r->mode = mode; | |
1038 | } | |
1039 | } | |
1040 | \f | |
1041 | /* If there is only one output reload, and it is not for an earlyclobber | |
1042 | operand, try to combine it with a (logically unrelated) input reload | |
1043 | to reduce the number of reload registers needed. | |
1044 | ||
1045 | This is safe if the input reload does not appear in | |
1046 | the value being output-reloaded, because this implies | |
1047 | it is not needed any more once the original insn completes. | |
1048 | ||
1049 | If that doesn't work, see we can use any of the registers that | |
1050 | die in this insn as a reload register. We can if it is of the right | |
1051 | class and does not appear in the value being output-reloaded. */ | |
1052 | ||
1053 | static void | |
1054 | combine_reloads () | |
1055 | { | |
1056 | int i; | |
1057 | int output_reload = -1; | |
1058 | rtx note; | |
1059 | ||
1060 | /* Find the output reload; return unless there is exactly one | |
1061 | and that one is mandatory. */ | |
1062 | ||
1063 | for (i = 0; i < n_reloads; i++) | |
1064 | if (reload_out[i] != 0) | |
1065 | { | |
1066 | if (output_reload >= 0) | |
1067 | return; | |
1068 | output_reload = i; | |
1069 | } | |
1070 | ||
1071 | if (output_reload < 0 || reload_optional[output_reload]) | |
1072 | return; | |
1073 | ||
1074 | /* An input-output reload isn't combinable. */ | |
1075 | ||
1076 | if (reload_in[output_reload] != 0) | |
1077 | return; | |
1078 | ||
6dc42e49 | 1079 | /* If this reload is for an earlyclobber operand, we can't do anything. */ |
eab89b90 RK |
1080 | |
1081 | for (i = 0; i < n_earlyclobbers; i++) | |
1082 | if (reload_out[output_reload] == reload_earlyclobbers[i]) | |
1083 | return; | |
1084 | ||
1085 | /* Check each input reload; can we combine it? */ | |
1086 | ||
1087 | for (i = 0; i < n_reloads; i++) | |
1088 | if (reload_in[i] && ! reload_optional[i] && ! reload_nocombine[i] | |
1089 | /* Life span of this reload must not extend past main insn. */ | |
1090 | && reload_when_needed[i] != RELOAD_FOR_OUTPUT_RELOAD_ADDRESS | |
1091 | && reload_inmode[i] == reload_outmode[output_reload] | |
1092 | && reload_inc[i] == 0 | |
1093 | && reload_reg_rtx[i] == 0 | |
1094 | && reload_strict_low[i] == 0 | |
1095 | /* Don't combine two reloads with different secondary reloads. */ | |
1096 | && (reload_secondary_reload[i] == reload_secondary_reload[output_reload] | |
1097 | || reload_secondary_reload[i] == -1 | |
1098 | || reload_secondary_reload[output_reload] == -1) | |
1099 | && (reg_class_subset_p (reload_reg_class[i], | |
1100 | reload_reg_class[output_reload]) | |
1101 | || reg_class_subset_p (reload_reg_class[output_reload], | |
1102 | reload_reg_class[i])) | |
1103 | && (MATCHES (reload_in[i], reload_out[output_reload]) | |
1104 | /* Args reversed because the first arg seems to be | |
1105 | the one that we imagine being modified | |
1106 | while the second is the one that might be affected. */ | |
1107 | || (! reg_overlap_mentioned_p (reload_out[output_reload], | |
1108 | reload_in[i]) | |
1109 | /* However, if the input is a register that appears inside | |
1110 | the output, then we also can't share. | |
1111 | Imagine (set (mem (reg 69)) (plus (reg 69) ...)). | |
1112 | If the same reload reg is used for both reg 69 and the | |
1113 | result to be stored in memory, then that result | |
1114 | will clobber the address of the memory ref. */ | |
1115 | && ! (GET_CODE (reload_in[i]) == REG | |
1116 | && reg_overlap_mentioned_p (reload_in[i], | |
1117 | reload_out[output_reload]))))) | |
1118 | { | |
1119 | int j; | |
1120 | ||
1121 | /* We have found a reload to combine with! */ | |
1122 | reload_out[i] = reload_out[output_reload]; | |
1123 | reload_outmode[i] = reload_outmode[output_reload]; | |
1124 | /* Mark the old output reload as inoperative. */ | |
1125 | reload_out[output_reload] = 0; | |
1126 | /* The combined reload is needed for the entire insn. */ | |
1127 | reload_needed_for_multiple[i] = 1; | |
1128 | reload_when_needed[i] = RELOAD_OTHER; | |
1129 | /* If the output reload had a secondary reload, copy it. */ | |
1130 | if (reload_secondary_reload[output_reload] != -1) | |
1131 | reload_secondary_reload[i] = reload_secondary_reload[output_reload]; | |
1132 | /* If required, minimize the register class. */ | |
1133 | if (reg_class_subset_p (reload_reg_class[output_reload], | |
1134 | reload_reg_class[i])) | |
1135 | reload_reg_class[i] = reload_reg_class[output_reload]; | |
1136 | ||
1137 | /* Transfer all replacements from the old reload to the combined. */ | |
1138 | for (j = 0; j < n_replacements; j++) | |
1139 | if (replacements[j].what == output_reload) | |
1140 | replacements[j].what = i; | |
1141 | ||
1142 | return; | |
1143 | } | |
1144 | ||
1145 | /* If this insn has only one operand that is modified or written (assumed | |
1146 | to be the first), it must be the one corresponding to this reload. It | |
1147 | is safe to use anything that dies in this insn for that output provided | |
1148 | that it does not occur in the output (we already know it isn't an | |
1149 | earlyclobber. If this is an asm insn, give up. */ | |
1150 | ||
1151 | if (INSN_CODE (this_insn) == -1) | |
1152 | return; | |
1153 | ||
1154 | for (i = 1; i < insn_n_operands[INSN_CODE (this_insn)]; i++) | |
1155 | if (insn_operand_constraint[INSN_CODE (this_insn)][i][0] == '=' | |
1156 | || insn_operand_constraint[INSN_CODE (this_insn)][i][0] == '+') | |
1157 | return; | |
1158 | ||
1159 | /* See if some hard register that dies in this insn and is not used in | |
1160 | the output is the right class. Only works if the register we pick | |
1161 | up can fully hold our output reload. */ | |
1162 | for (note = REG_NOTES (this_insn); note; note = XEXP (note, 1)) | |
1163 | if (REG_NOTE_KIND (note) == REG_DEAD | |
1164 | && GET_CODE (XEXP (note, 0)) == REG | |
1165 | && ! reg_overlap_mentioned_p (XEXP (note, 0), | |
1166 | reload_out[output_reload]) | |
1167 | && REGNO (XEXP (note, 0)) < FIRST_PSEUDO_REGISTER | |
1168 | && HARD_REGNO_MODE_OK (REGNO (XEXP (note, 0)), reload_outmode[output_reload]) | |
1169 | && TEST_HARD_REG_BIT (reg_class_contents[(int) reload_reg_class[output_reload]], | |
1170 | REGNO (XEXP (note, 0))) | |
1171 | && (HARD_REGNO_NREGS (REGNO (XEXP (note, 0)), reload_outmode[output_reload]) | |
1172 | <= HARD_REGNO_NREGS (REGNO (XEXP (note, 0)), GET_MODE (XEXP (note, 0)))) | |
1173 | && ! fixed_regs[REGNO (XEXP (note, 0))]) | |
1174 | { | |
1175 | reload_reg_rtx[output_reload] = gen_rtx (REG, | |
1176 | reload_outmode[output_reload], | |
1177 | REGNO (XEXP (note, 0))); | |
1178 | return; | |
1179 | } | |
1180 | } | |
1181 | \f | |
1182 | /* Try to find a reload register for an in-out reload (expressions IN and OUT). | |
1183 | See if one of IN and OUT is a register that may be used; | |
1184 | this is desirable since a spill-register won't be needed. | |
1185 | If so, return the register rtx that proves acceptable. | |
1186 | ||
1187 | INLOC and OUTLOC are locations where IN and OUT appear in the insn. | |
1188 | CLASS is the register class required for the reload. | |
1189 | ||
1190 | If FOR_REAL is >= 0, it is the number of the reload, | |
1191 | and in some cases when it can be discovered that OUT doesn't need | |
1192 | to be computed, clear out reload_out[FOR_REAL]. | |
1193 | ||
1194 | If FOR_REAL is -1, this should not be done, because this call | |
1195 | is just to see if a register can be found, not to find and install it. */ | |
1196 | ||
1197 | static rtx | |
1198 | find_dummy_reload (real_in, real_out, inloc, outloc, class, for_real) | |
1199 | rtx real_in, real_out; | |
1200 | rtx *inloc, *outloc; | |
1201 | enum reg_class class; | |
1202 | int for_real; | |
1203 | { | |
1204 | rtx in = real_in; | |
1205 | rtx out = real_out; | |
1206 | int in_offset = 0; | |
1207 | int out_offset = 0; | |
1208 | rtx value = 0; | |
1209 | ||
1210 | /* If operands exceed a word, we can't use either of them | |
1211 | unless they have the same size. */ | |
1212 | if (GET_MODE_SIZE (GET_MODE (real_out)) != GET_MODE_SIZE (GET_MODE (real_in)) | |
1213 | && (GET_MODE_SIZE (GET_MODE (real_out)) > UNITS_PER_WORD | |
1214 | || GET_MODE_SIZE (GET_MODE (real_in)) > UNITS_PER_WORD)) | |
1215 | return 0; | |
1216 | ||
1217 | /* Find the inside of any subregs. */ | |
1218 | while (GET_CODE (out) == SUBREG) | |
1219 | { | |
1220 | out_offset = SUBREG_WORD (out); | |
1221 | out = SUBREG_REG (out); | |
1222 | } | |
1223 | while (GET_CODE (in) == SUBREG) | |
1224 | { | |
1225 | in_offset = SUBREG_WORD (in); | |
1226 | in = SUBREG_REG (in); | |
1227 | } | |
1228 | ||
1229 | /* Narrow down the reg class, the same way push_reload will; | |
1230 | otherwise we might find a dummy now, but push_reload won't. */ | |
1231 | class = PREFERRED_RELOAD_CLASS (in, class); | |
1232 | ||
1233 | /* See if OUT will do. */ | |
1234 | if (GET_CODE (out) == REG | |
1235 | && REGNO (out) < FIRST_PSEUDO_REGISTER) | |
1236 | { | |
1237 | register int regno = REGNO (out) + out_offset; | |
1238 | int nwords = HARD_REGNO_NREGS (regno, GET_MODE (real_out)); | |
1239 | ||
1240 | /* When we consider whether the insn uses OUT, | |
1241 | ignore references within IN. They don't prevent us | |
1242 | from copying IN into OUT, because those refs would | |
1243 | move into the insn that reloads IN. | |
1244 | ||
1245 | However, we only ignore IN in its role as this reload. | |
1246 | If the insn uses IN elsewhere and it contains OUT, | |
1247 | that counts. We can't be sure it's the "same" operand | |
1248 | so it might not go through this reload. */ | |
1249 | *inloc = const0_rtx; | |
1250 | ||
1251 | if (regno < FIRST_PSEUDO_REGISTER | |
1252 | /* A fixed reg that can overlap other regs better not be used | |
1253 | for reloading in any way. */ | |
1254 | #ifdef OVERLAPPING_REGNO_P | |
1255 | && ! (fixed_regs[regno] && OVERLAPPING_REGNO_P (regno)) | |
1256 | #endif | |
1257 | && ! refers_to_regno_for_reload_p (regno, regno + nwords, | |
1258 | PATTERN (this_insn), outloc)) | |
1259 | { | |
1260 | int i; | |
1261 | for (i = 0; i < nwords; i++) | |
1262 | if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class], | |
1263 | regno + i)) | |
1264 | break; | |
1265 | ||
1266 | if (i == nwords) | |
1267 | { | |
1268 | if (GET_CODE (real_out) == REG) | |
1269 | value = real_out; | |
1270 | else | |
1271 | value = gen_rtx (REG, GET_MODE (real_out), regno); | |
1272 | } | |
1273 | } | |
1274 | ||
1275 | *inloc = real_in; | |
1276 | } | |
1277 | ||
1278 | /* Consider using IN if OUT was not acceptable | |
1279 | or if OUT dies in this insn (like the quotient in a divmod insn). | |
1280 | We can't use IN unless it is dies in this insn, | |
1281 | which means we must know accurately which hard regs are live. | |
1282 | Also, the result can't go in IN if IN is used within OUT. */ | |
1283 | if (hard_regs_live_known | |
1284 | && GET_CODE (in) == REG | |
1285 | && REGNO (in) < FIRST_PSEUDO_REGISTER | |
1286 | && (value == 0 | |
1287 | || find_reg_note (this_insn, REG_UNUSED, real_out)) | |
1288 | && find_reg_note (this_insn, REG_DEAD, real_in) | |
1289 | && !fixed_regs[REGNO (in)] | |
1290 | && HARD_REGNO_MODE_OK (REGNO (in), GET_MODE (out))) | |
1291 | { | |
1292 | register int regno = REGNO (in) + in_offset; | |
1293 | int nwords = HARD_REGNO_NREGS (regno, GET_MODE (real_in)); | |
1294 | ||
1295 | if (! refers_to_regno_for_reload_p (regno, regno + nwords, out, 0) | |
1296 | && ! hard_reg_set_here_p (regno, regno + nwords, | |
1297 | PATTERN (this_insn))) | |
1298 | { | |
1299 | int i; | |
1300 | for (i = 0; i < nwords; i++) | |
1301 | if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class], | |
1302 | regno + i)) | |
1303 | break; | |
1304 | ||
1305 | if (i == nwords) | |
1306 | { | |
1307 | /* If we were going to use OUT as the reload reg | |
1308 | and changed our mind, it means OUT is a dummy that | |
1309 | dies here. So don't bother copying value to it. */ | |
1310 | if (for_real >= 0 && value == real_out) | |
1311 | reload_out[for_real] = 0; | |
1312 | if (GET_CODE (real_in) == REG) | |
1313 | value = real_in; | |
1314 | else | |
1315 | value = gen_rtx (REG, GET_MODE (real_in), regno); | |
1316 | } | |
1317 | } | |
1318 | } | |
1319 | ||
1320 | return value; | |
1321 | } | |
1322 | \f | |
1323 | /* This page contains subroutines used mainly for determining | |
1324 | whether the IN or an OUT of a reload can serve as the | |
1325 | reload register. */ | |
1326 | ||
1327 | /* Return 1 if expression X alters a hard reg in the range | |
1328 | from BEG_REGNO (inclusive) to END_REGNO (exclusive), | |
1329 | either explicitly or in the guise of a pseudo-reg allocated to REGNO. | |
1330 | X should be the body of an instruction. */ | |
1331 | ||
1332 | static int | |
1333 | hard_reg_set_here_p (beg_regno, end_regno, x) | |
1334 | register int beg_regno, end_regno; | |
1335 | rtx x; | |
1336 | { | |
1337 | if (GET_CODE (x) == SET || GET_CODE (x) == CLOBBER) | |
1338 | { | |
1339 | register rtx op0 = SET_DEST (x); | |
1340 | while (GET_CODE (op0) == SUBREG) | |
1341 | op0 = SUBREG_REG (op0); | |
1342 | if (GET_CODE (op0) == REG) | |
1343 | { | |
1344 | register int r = REGNO (op0); | |
1345 | /* See if this reg overlaps range under consideration. */ | |
1346 | if (r < end_regno | |
1347 | && r + HARD_REGNO_NREGS (r, GET_MODE (op0)) > beg_regno) | |
1348 | return 1; | |
1349 | } | |
1350 | } | |
1351 | else if (GET_CODE (x) == PARALLEL) | |
1352 | { | |
1353 | register int i = XVECLEN (x, 0) - 1; | |
1354 | for (; i >= 0; i--) | |
1355 | if (hard_reg_set_here_p (beg_regno, end_regno, XVECEXP (x, 0, i))) | |
1356 | return 1; | |
1357 | } | |
1358 | ||
1359 | return 0; | |
1360 | } | |
1361 | ||
1362 | /* Return 1 if ADDR is a valid memory address for mode MODE, | |
1363 | and check that each pseudo reg has the proper kind of | |
1364 | hard reg. */ | |
1365 | ||
1366 | int | |
1367 | strict_memory_address_p (mode, addr) | |
1368 | enum machine_mode mode; | |
1369 | register rtx addr; | |
1370 | { | |
1371 | GO_IF_LEGITIMATE_ADDRESS (mode, addr, win); | |
1372 | return 0; | |
1373 | ||
1374 | win: | |
1375 | return 1; | |
1376 | } | |
1377 | ||
1378 | \f | |
1379 | /* Like rtx_equal_p except that it allows a REG and a SUBREG to match | |
1380 | if they are the same hard reg, and has special hacks for | |
1381 | autoincrement and autodecrement. | |
1382 | This is specifically intended for find_reloads to use | |
1383 | in determining whether two operands match. | |
1384 | X is the operand whose number is the lower of the two. | |
1385 | ||
1386 | The value is 2 if Y contains a pre-increment that matches | |
1387 | a non-incrementing address in X. */ | |
1388 | ||
1389 | /* ??? To be completely correct, we should arrange to pass | |
1390 | for X the output operand and for Y the input operand. | |
1391 | For now, we assume that the output operand has the lower number | |
1392 | because that is natural in (SET output (... input ...)). */ | |
1393 | ||
1394 | int | |
1395 | operands_match_p (x, y) | |
1396 | register rtx x, y; | |
1397 | { | |
1398 | register int i; | |
1399 | register RTX_CODE code = GET_CODE (x); | |
1400 | register char *fmt; | |
1401 | int success_2; | |
1402 | ||
1403 | if (x == y) | |
1404 | return 1; | |
1405 | if ((code == REG || (code == SUBREG && GET_CODE (SUBREG_REG (x)) == REG)) | |
1406 | && (GET_CODE (y) == REG || (GET_CODE (y) == SUBREG | |
1407 | && GET_CODE (SUBREG_REG (y)) == REG))) | |
1408 | { | |
1409 | register int j; | |
1410 | ||
1411 | if (code == SUBREG) | |
1412 | { | |
1413 | i = REGNO (SUBREG_REG (x)); | |
1414 | if (i >= FIRST_PSEUDO_REGISTER) | |
1415 | goto slow; | |
1416 | i += SUBREG_WORD (x); | |
1417 | } | |
1418 | else | |
1419 | i = REGNO (x); | |
1420 | ||
1421 | if (GET_CODE (y) == SUBREG) | |
1422 | { | |
1423 | j = REGNO (SUBREG_REG (y)); | |
1424 | if (j >= FIRST_PSEUDO_REGISTER) | |
1425 | goto slow; | |
1426 | j += SUBREG_WORD (y); | |
1427 | } | |
1428 | else | |
1429 | j = REGNO (y); | |
1430 | ||
1431 | return i == j; | |
1432 | } | |
1433 | /* If two operands must match, because they are really a single | |
1434 | operand of an assembler insn, then two postincrements are invalid | |
1435 | because the assembler insn would increment only once. | |
1436 | On the other hand, an postincrement matches ordinary indexing | |
1437 | if the postincrement is the output operand. */ | |
1438 | if (code == POST_DEC || code == POST_INC) | |
1439 | return operands_match_p (XEXP (x, 0), y); | |
1440 | /* Two preincrements are invalid | |
1441 | because the assembler insn would increment only once. | |
1442 | On the other hand, an preincrement matches ordinary indexing | |
1443 | if the preincrement is the input operand. | |
1444 | In this case, return 2, since some callers need to do special | |
1445 | things when this happens. */ | |
1446 | if (GET_CODE (y) == PRE_DEC || GET_CODE (y) == PRE_INC) | |
1447 | return operands_match_p (x, XEXP (y, 0)) ? 2 : 0; | |
1448 | ||
1449 | slow: | |
1450 | ||
1451 | /* Now we have disposed of all the cases | |
1452 | in which different rtx codes can match. */ | |
1453 | if (code != GET_CODE (y)) | |
1454 | return 0; | |
1455 | if (code == LABEL_REF) | |
1456 | return XEXP (x, 0) == XEXP (y, 0); | |
1457 | if (code == SYMBOL_REF) | |
1458 | return XSTR (x, 0) == XSTR (y, 0); | |
1459 | ||
1460 | /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent. */ | |
1461 | ||
1462 | if (GET_MODE (x) != GET_MODE (y)) | |
1463 | return 0; | |
1464 | ||
1465 | /* Compare the elements. If any pair of corresponding elements | |
1466 | fail to match, return 0 for the whole things. */ | |
1467 | ||
1468 | success_2 = 0; | |
1469 | fmt = GET_RTX_FORMAT (code); | |
1470 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
1471 | { | |
1472 | int val; | |
1473 | switch (fmt[i]) | |
1474 | { | |
1475 | case 'i': | |
1476 | if (XINT (x, i) != XINT (y, i)) | |
1477 | return 0; | |
1478 | break; | |
1479 | ||
1480 | case 'e': | |
1481 | val = operands_match_p (XEXP (x, i), XEXP (y, i)); | |
1482 | if (val == 0) | |
1483 | return 0; | |
1484 | /* If any subexpression returns 2, | |
1485 | we should return 2 if we are successful. */ | |
1486 | if (val == 2) | |
1487 | success_2 = 1; | |
1488 | break; | |
1489 | ||
1490 | case '0': | |
1491 | break; | |
1492 | ||
1493 | /* It is believed that rtx's at this level will never | |
1494 | contain anything but integers and other rtx's, | |
1495 | except for within LABEL_REFs and SYMBOL_REFs. */ | |
1496 | default: | |
1497 | abort (); | |
1498 | } | |
1499 | } | |
1500 | return 1 + success_2; | |
1501 | } | |
1502 | \f | |
1503 | /* Return the number of times character C occurs in string S. */ | |
1504 | ||
1505 | static int | |
1506 | n_occurrences (c, s) | |
1507 | char c; | |
1508 | char *s; | |
1509 | { | |
1510 | int n = 0; | |
1511 | while (*s) | |
1512 | n += (*s++ == c); | |
1513 | return n; | |
1514 | } | |
1515 | \f | |
1516 | struct decomposition | |
1517 | { | |
1518 | int reg_flag; | |
1519 | int safe; | |
1520 | rtx base; | |
1521 | int start; | |
1522 | int end; | |
1523 | }; | |
1524 | ||
1525 | /* Describe the range of registers or memory referenced by X. | |
1526 | If X is a register, set REG_FLAG and put the first register | |
1527 | number into START and the last plus one into END. | |
1528 | If X is a memory reference, put a base address into BASE | |
1529 | and a range of integer offsets into START and END. | |
1530 | If X is pushing on the stack, we can assume it causes no trouble, | |
1531 | so we set the SAFE field. */ | |
1532 | ||
1533 | static struct decomposition | |
1534 | decompose (x) | |
1535 | rtx x; | |
1536 | { | |
1537 | struct decomposition val; | |
1538 | int all_const = 0; | |
1539 | ||
1540 | val.reg_flag = 0; | |
1541 | val.safe = 0; | |
1542 | if (GET_CODE (x) == MEM) | |
1543 | { | |
1544 | rtx base, offset = 0; | |
1545 | rtx addr = XEXP (x, 0); | |
1546 | ||
1547 | if (GET_CODE (addr) == PRE_DEC || GET_CODE (addr) == PRE_INC | |
1548 | || GET_CODE (addr) == POST_DEC || GET_CODE (addr) == POST_INC) | |
1549 | { | |
1550 | val.base = XEXP (addr, 0); | |
1551 | val.start = - GET_MODE_SIZE (GET_MODE (x)); | |
1552 | val.end = GET_MODE_SIZE (GET_MODE (x)); | |
1553 | val.safe = REGNO (val.base) == STACK_POINTER_REGNUM; | |
1554 | return val; | |
1555 | } | |
1556 | ||
1557 | if (GET_CODE (addr) == CONST) | |
1558 | { | |
1559 | addr = XEXP (addr, 0); | |
1560 | all_const = 1; | |
1561 | } | |
1562 | if (GET_CODE (addr) == PLUS) | |
1563 | { | |
1564 | if (CONSTANT_P (XEXP (addr, 0))) | |
1565 | { | |
1566 | base = XEXP (addr, 1); | |
1567 | offset = XEXP (addr, 0); | |
1568 | } | |
1569 | else if (CONSTANT_P (XEXP (addr, 1))) | |
1570 | { | |
1571 | base = XEXP (addr, 0); | |
1572 | offset = XEXP (addr, 1); | |
1573 | } | |
1574 | } | |
1575 | ||
1576 | if (offset == 0) | |
1577 | { | |
1578 | base = addr; | |
1579 | offset = const0_rtx; | |
1580 | } | |
1581 | if (GET_CODE (offset) == CONST) | |
1582 | offset = XEXP (offset, 0); | |
1583 | if (GET_CODE (offset) == PLUS) | |
1584 | { | |
1585 | if (GET_CODE (XEXP (offset, 0)) == CONST_INT) | |
1586 | { | |
1587 | base = gen_rtx (PLUS, GET_MODE (base), base, XEXP (offset, 1)); | |
1588 | offset = XEXP (offset, 0); | |
1589 | } | |
1590 | else if (GET_CODE (XEXP (offset, 1)) == CONST_INT) | |
1591 | { | |
1592 | base = gen_rtx (PLUS, GET_MODE (base), base, XEXP (offset, 0)); | |
1593 | offset = XEXP (offset, 1); | |
1594 | } | |
1595 | else | |
1596 | { | |
1597 | base = gen_rtx (PLUS, GET_MODE (base), base, offset); | |
1598 | offset = const0_rtx; | |
1599 | } | |
1600 | } | |
1601 | else if (GET_CODE (offset) != CONST_INT) | |
1602 | { | |
1603 | base = gen_rtx (PLUS, GET_MODE (base), base, offset); | |
1604 | offset = const0_rtx; | |
1605 | } | |
1606 | ||
1607 | if (all_const && GET_CODE (base) == PLUS) | |
1608 | base = gen_rtx (CONST, GET_MODE (base), base); | |
1609 | ||
1610 | if (GET_CODE (offset) != CONST_INT) | |
1611 | abort (); | |
1612 | ||
1613 | val.start = INTVAL (offset); | |
1614 | val.end = val.start + GET_MODE_SIZE (GET_MODE (x)); | |
1615 | val.base = base; | |
1616 | return val; | |
1617 | } | |
1618 | else if (GET_CODE (x) == REG) | |
1619 | { | |
1620 | val.reg_flag = 1; | |
1621 | val.start = true_regnum (x); | |
1622 | if (val.start < 0) | |
1623 | { | |
1624 | /* A pseudo with no hard reg. */ | |
1625 | val.start = REGNO (x); | |
1626 | val.end = val.start + 1; | |
1627 | } | |
1628 | else | |
1629 | /* A hard reg. */ | |
1630 | val.end = val.start + HARD_REGNO_NREGS (val.start, GET_MODE (x)); | |
1631 | } | |
1632 | else if (GET_CODE (x) == SUBREG) | |
1633 | { | |
1634 | if (GET_CODE (SUBREG_REG (x)) != REG) | |
1635 | /* This could be more precise, but it's good enough. */ | |
1636 | return decompose (SUBREG_REG (x)); | |
1637 | val.reg_flag = 1; | |
1638 | val.start = true_regnum (x); | |
1639 | if (val.start < 0) | |
1640 | return decompose (SUBREG_REG (x)); | |
1641 | else | |
1642 | /* A hard reg. */ | |
1643 | val.end = val.start + HARD_REGNO_NREGS (val.start, GET_MODE (x)); | |
1644 | } | |
1645 | else if (CONSTANT_P (x) | |
1646 | /* This hasn't been assigned yet, so it can't conflict yet. */ | |
1647 | || GET_CODE (x) == SCRATCH) | |
1648 | val.safe = 1; | |
1649 | else | |
1650 | abort (); | |
1651 | return val; | |
1652 | } | |
1653 | ||
1654 | /* Return 1 if altering Y will not modify the value of X. | |
1655 | Y is also described by YDATA, which should be decompose (Y). */ | |
1656 | ||
1657 | static int | |
1658 | immune_p (x, y, ydata) | |
1659 | rtx x, y; | |
1660 | struct decomposition ydata; | |
1661 | { | |
1662 | struct decomposition xdata; | |
1663 | ||
1664 | if (ydata.reg_flag) | |
1665 | return !refers_to_regno_for_reload_p (ydata.start, ydata.end, x, 0); | |
1666 | if (ydata.safe) | |
1667 | return 1; | |
1668 | ||
1669 | if (GET_CODE (y) != MEM) | |
1670 | abort (); | |
1671 | /* If Y is memory and X is not, Y can't affect X. */ | |
1672 | if (GET_CODE (x) != MEM) | |
1673 | return 1; | |
1674 | ||
1675 | xdata = decompose (x); | |
1676 | ||
1677 | if (! rtx_equal_p (xdata.base, ydata.base)) | |
1678 | { | |
1679 | /* If bases are distinct symbolic constants, there is no overlap. */ | |
1680 | if (CONSTANT_P (xdata.base) && CONSTANT_P (ydata.base)) | |
1681 | return 1; | |
1682 | /* Constants and stack slots never overlap. */ | |
1683 | if (CONSTANT_P (xdata.base) | |
1684 | && (ydata.base == frame_pointer_rtx | |
1685 | || ydata.base == stack_pointer_rtx)) | |
1686 | return 1; | |
1687 | if (CONSTANT_P (ydata.base) | |
1688 | && (xdata.base == frame_pointer_rtx | |
1689 | || xdata.base == stack_pointer_rtx)) | |
1690 | return 1; | |
1691 | /* If either base is variable, we don't know anything. */ | |
1692 | return 0; | |
1693 | } | |
1694 | ||
1695 | ||
1696 | return (xdata.start >= ydata.end || ydata.start >= xdata.end); | |
1697 | } | |
44ace968 JW |
1698 | |
1699 | /* Similiar, but calls decompose. */ | |
1700 | ||
1701 | int | |
1702 | safe_from_earlyclobber (op, clobber) | |
1703 | rtx op, clobber; | |
1704 | { | |
1705 | struct decomposition early_data; | |
1706 | ||
1707 | early_data = decompose (clobber); | |
1708 | return immune_p (op, clobber, early_data); | |
1709 | } | |
eab89b90 RK |
1710 | \f |
1711 | /* Main entry point of this file: search the body of INSN | |
1712 | for values that need reloading and record them with push_reload. | |
1713 | REPLACE nonzero means record also where the values occur | |
1714 | so that subst_reloads can be used. | |
1715 | ||
1716 | IND_LEVELS says how many levels of indirection are supported by this | |
1717 | machine; a value of zero means that a memory reference is not a valid | |
1718 | memory address. | |
1719 | ||
1720 | LIVE_KNOWN says we have valid information about which hard | |
1721 | regs are live at each point in the program; this is true when | |
1722 | we are called from global_alloc but false when stupid register | |
1723 | allocation has been done. | |
1724 | ||
1725 | RELOAD_REG_P if nonzero is a vector indexed by hard reg number | |
1726 | which is nonnegative if the reg has been commandeered for reloading into. | |
1727 | It is copied into STATIC_RELOAD_REG_P and referenced from there | |
1728 | by various subroutines. */ | |
1729 | ||
1730 | void | |
1731 | find_reloads (insn, replace, ind_levels, live_known, reload_reg_p) | |
1732 | rtx insn; | |
1733 | int replace, ind_levels; | |
1734 | int live_known; | |
1735 | short *reload_reg_p; | |
1736 | { | |
1737 | rtx non_reloaded_operands[MAX_RECOG_OPERANDS]; | |
1738 | int n_non_reloaded_operands = 0; | |
1739 | #ifdef REGISTER_CONSTRAINTS | |
1740 | ||
1741 | enum reload_modified { RELOAD_NOTHING, RELOAD_READ, RELOAD_READ_WRITE, RELOAD_WRITE }; | |
1742 | ||
1743 | register int insn_code_number; | |
1744 | register int i; | |
1745 | int noperands; | |
1746 | /* These are the constraints for the insn. We don't change them. */ | |
1747 | char *constraints1[MAX_RECOG_OPERANDS]; | |
1748 | /* These start out as the constraints for the insn | |
1749 | and they are chewed up as we consider alternatives. */ | |
1750 | char *constraints[MAX_RECOG_OPERANDS]; | |
1751 | /* These are the preferred classes for an operand, or NO_REGS if it isn't | |
1752 | a register. */ | |
1753 | enum reg_class preferred_class[MAX_RECOG_OPERANDS]; | |
1754 | char pref_or_nothing[MAX_RECOG_OPERANDS]; | |
1755 | /* Nonzero for a MEM operand whose entire address needs a reload. */ | |
1756 | int address_reloaded[MAX_RECOG_OPERANDS]; | |
1757 | int no_input_reloads = 0, no_output_reloads = 0; | |
1758 | int n_alternatives; | |
1759 | int this_alternative[MAX_RECOG_OPERANDS]; | |
1760 | char this_alternative_win[MAX_RECOG_OPERANDS]; | |
1761 | char this_alternative_offmemok[MAX_RECOG_OPERANDS]; | |
1762 | char this_alternative_earlyclobber[MAX_RECOG_OPERANDS]; | |
1763 | int this_alternative_matches[MAX_RECOG_OPERANDS]; | |
1764 | int swapped; | |
1765 | int goal_alternative[MAX_RECOG_OPERANDS]; | |
1766 | int this_alternative_number; | |
1767 | int goal_alternative_number; | |
1768 | int operand_reloadnum[MAX_RECOG_OPERANDS]; | |
1769 | int goal_alternative_matches[MAX_RECOG_OPERANDS]; | |
1770 | int goal_alternative_matched[MAX_RECOG_OPERANDS]; | |
1771 | char goal_alternative_win[MAX_RECOG_OPERANDS]; | |
1772 | char goal_alternative_offmemok[MAX_RECOG_OPERANDS]; | |
1773 | char goal_alternative_earlyclobber[MAX_RECOG_OPERANDS]; | |
1774 | int goal_alternative_swapped; | |
1775 | enum reload_modified modified[MAX_RECOG_OPERANDS]; | |
1776 | int best; | |
1777 | int commutative; | |
1778 | char operands_match[MAX_RECOG_OPERANDS][MAX_RECOG_OPERANDS]; | |
1779 | rtx substed_operand[MAX_RECOG_OPERANDS]; | |
1780 | rtx body = PATTERN (insn); | |
1781 | rtx set = single_set (insn); | |
1782 | int goal_earlyclobber, this_earlyclobber; | |
1783 | enum machine_mode operand_mode[MAX_RECOG_OPERANDS]; | |
1784 | ||
1785 | this_insn = insn; | |
1786 | this_insn_is_asm = 0; /* Tentative. */ | |
1787 | n_reloads = 0; | |
1788 | n_replacements = 0; | |
1789 | n_memlocs = 0; | |
1790 | n_earlyclobbers = 0; | |
1791 | replace_reloads = replace; | |
1792 | hard_regs_live_known = live_known; | |
1793 | static_reload_reg_p = reload_reg_p; | |
1794 | ||
1795 | /* JUMP_INSNs and CALL_INSNs are not allowed to have any output reloads; | |
1796 | neither are insns that SET cc0. Insns that use CC0 are not allowed | |
1797 | to have any input reloads. */ | |
1798 | if (GET_CODE (insn) == JUMP_INSN || GET_CODE (insn) == CALL_INSN) | |
1799 | no_output_reloads = 1; | |
1800 | ||
1801 | #ifdef HAVE_cc0 | |
1802 | if (reg_referenced_p (cc0_rtx, PATTERN (insn))) | |
1803 | no_input_reloads = 1; | |
1804 | if (reg_set_p (cc0_rtx, PATTERN (insn))) | |
1805 | no_output_reloads = 1; | |
1806 | #endif | |
1807 | ||
1808 | /* Find what kind of insn this is. NOPERANDS gets number of operands. | |
1809 | Make OPERANDS point to a vector of operand values. | |
1810 | Make OPERAND_LOCS point to a vector of pointers to | |
1811 | where the operands were found. | |
1812 | Fill CONSTRAINTS and CONSTRAINTS1 with pointers to the | |
1813 | constraint-strings for this insn. | |
1814 | Return if the insn needs no reload processing. */ | |
1815 | ||
1816 | switch (GET_CODE (body)) | |
1817 | { | |
1818 | case USE: | |
1819 | case CLOBBER: | |
1820 | case ASM_INPUT: | |
1821 | case ADDR_VEC: | |
1822 | case ADDR_DIFF_VEC: | |
1823 | return; | |
1824 | ||
1825 | case SET: | |
1826 | /* Dispose quickly of (set (reg..) (reg..)) if both have hard regs and it | |
1827 | is cheap to move between them. If it is not, there may not be an insn | |
1828 | to do the copy, so we may need a reload. */ | |
1829 | if (GET_CODE (SET_DEST (body)) == REG | |
1830 | && REGNO (SET_DEST (body)) < FIRST_PSEUDO_REGISTER | |
1831 | && GET_CODE (SET_SRC (body)) == REG | |
1832 | && REGNO (SET_SRC (body)) < FIRST_PSEUDO_REGISTER | |
1833 | && REGISTER_MOVE_COST (REGNO_REG_CLASS (REGNO (SET_SRC (body))), | |
1834 | REGNO_REG_CLASS (REGNO (SET_DEST (body)))) == 2) | |
1835 | return; | |
1836 | case PARALLEL: | |
1837 | case ASM_OPERANDS: | |
1838 | noperands = asm_noperands (body); | |
1839 | if (noperands >= 0) | |
1840 | { | |
1841 | /* This insn is an `asm' with operands. */ | |
1842 | ||
1843 | insn_code_number = -1; | |
1844 | this_insn_is_asm = 1; | |
1845 | ||
1846 | /* expand_asm_operands makes sure there aren't too many operands. */ | |
1847 | if (noperands > MAX_RECOG_OPERANDS) | |
1848 | abort (); | |
1849 | ||
1850 | /* Now get the operand values and constraints out of the insn. */ | |
1851 | ||
1852 | decode_asm_operands (body, recog_operand, recog_operand_loc, | |
1853 | constraints, operand_mode); | |
1854 | if (noperands > 0) | |
1855 | { | |
1856 | bcopy (constraints, constraints1, noperands * sizeof (char *)); | |
1857 | n_alternatives = n_occurrences (',', constraints[0]) + 1; | |
1858 | for (i = 1; i < noperands; i++) | |
d45cf215 | 1859 | if (n_alternatives != n_occurrences (',', constraints[i]) + 1) |
eab89b90 RK |
1860 | { |
1861 | error_for_asm (insn, "operand constraints differ in number of alternatives"); | |
1862 | /* Avoid further trouble with this insn. */ | |
1863 | PATTERN (insn) = gen_rtx (USE, VOIDmode, const0_rtx); | |
1864 | n_reloads = 0; | |
1865 | return; | |
1866 | } | |
1867 | } | |
1868 | break; | |
1869 | } | |
1870 | ||
1871 | default: | |
1872 | /* Ordinary insn: recognize it, get the operands via insn_extract | |
1873 | and get the constraints. */ | |
1874 | ||
1875 | insn_code_number = recog_memoized (insn); | |
1876 | if (insn_code_number < 0) | |
1877 | fatal_insn_not_found (insn); | |
1878 | ||
1879 | noperands = insn_n_operands[insn_code_number]; | |
1880 | n_alternatives = insn_n_alternatives[insn_code_number]; | |
1881 | /* Just return "no reloads" if insn has no operands with constraints. */ | |
1882 | if (n_alternatives == 0) | |
1883 | return; | |
1884 | insn_extract (insn); | |
1885 | for (i = 0; i < noperands; i++) | |
1886 | { | |
1887 | constraints[i] = constraints1[i] | |
1888 | = insn_operand_constraint[insn_code_number][i]; | |
1889 | operand_mode[i] = insn_operand_mode[insn_code_number][i]; | |
1890 | } | |
1891 | } | |
1892 | ||
1893 | if (noperands == 0) | |
1894 | return; | |
1895 | ||
1896 | commutative = -1; | |
1897 | ||
1898 | /* If we will need to know, later, whether some pair of operands | |
1899 | are the same, we must compare them now and save the result. | |
1900 | Reloading the base and index registers will clobber them | |
1901 | and afterward they will fail to match. */ | |
1902 | ||
1903 | for (i = 0; i < noperands; i++) | |
1904 | { | |
1905 | register char *p; | |
1906 | register int c; | |
1907 | ||
1908 | substed_operand[i] = recog_operand[i]; | |
1909 | p = constraints[i]; | |
1910 | ||
1911 | /* Scan this operand's constraint to see if it should match another. */ | |
1912 | ||
1913 | while (c = *p++) | |
1914 | if (c == '%') | |
1915 | { | |
1916 | /* The last operand should not be marked commutative. This | |
1917 | problem is hard to detect, so make it obvious by calling | |
1918 | abort here. */ | |
1919 | if (i == noperands - 1) | |
1920 | abort (); | |
1921 | ||
1922 | commutative = i; | |
1923 | } | |
1924 | else if (c >= '0' && c <= '9') | |
1925 | { | |
1926 | c -= '0'; | |
1927 | operands_match[c][i] | |
1928 | = operands_match_p (recog_operand[c], recog_operand[i]); | |
1929 | /* If C can be commuted with C+1, and C might need to match I, | |
1930 | then C+1 might also need to match I. */ | |
1931 | if (commutative >= 0) | |
1932 | { | |
1933 | if (c == commutative || c == commutative + 1) | |
1934 | { | |
1935 | int other = c + (c == commutative ? 1 : -1); | |
1936 | operands_match[other][i] | |
1937 | = operands_match_p (recog_operand[other], recog_operand[i]); | |
1938 | } | |
1939 | if (i == commutative || i == commutative + 1) | |
1940 | { | |
1941 | int other = i + (i == commutative ? 1 : -1); | |
1942 | operands_match[c][other] | |
1943 | = operands_match_p (recog_operand[c], recog_operand[other]); | |
1944 | } | |
1945 | /* Note that C is supposed to be less than I. | |
1946 | No need to consider altering both C and I | |
1947 | because in that case we would alter one into the other. */ | |
1948 | } | |
1949 | } | |
1950 | } | |
1951 | ||
1952 | /* Examine each operand that is a memory reference or memory address | |
1953 | and reload parts of the addresses into index registers. | |
1954 | While we are at it, initialize the array `modified'. | |
1955 | Also here any references to pseudo regs that didn't get hard regs | |
1956 | but are equivalent to constants get replaced in the insn itself | |
1957 | with those constants. Nobody will ever see them again. | |
1958 | ||
1959 | Finally, set up the preferred classes of each operand. */ | |
1960 | ||
1961 | for (i = 0; i < noperands; i++) | |
1962 | { | |
1963 | register RTX_CODE code = GET_CODE (recog_operand[i]); | |
1964 | modified[i] = RELOAD_READ; | |
1965 | address_reloaded[i] = 0; | |
eab89b90 RK |
1966 | |
1967 | if (constraints[i][0] == 'p') | |
1968 | { | |
1969 | find_reloads_address (VOIDmode, 0, | |
1970 | recog_operand[i], recog_operand_loc[i], | |
1971 | recog_operand[i], ind_levels); | |
1972 | substed_operand[i] = recog_operand[i] = *recog_operand_loc[i]; | |
1973 | } | |
1974 | else if (code == MEM) | |
1975 | { | |
1976 | if (find_reloads_address (GET_MODE (recog_operand[i]), | |
1977 | recog_operand_loc[i], | |
1978 | XEXP (recog_operand[i], 0), | |
1979 | &XEXP (recog_operand[i], 0), | |
1980 | recog_operand[i], ind_levels)) | |
1981 | address_reloaded[i] = 1; | |
1982 | substed_operand[i] = recog_operand[i] = *recog_operand_loc[i]; | |
1983 | } | |
1984 | else if (code == SUBREG) | |
1985 | substed_operand[i] = recog_operand[i] = *recog_operand_loc[i] | |
1986 | = find_reloads_toplev (recog_operand[i], ind_levels, | |
1987 | set != 0 | |
1988 | && &SET_DEST (set) == recog_operand_loc[i]); | |
1989 | else if (code == REG) | |
1990 | { | |
1991 | /* This is equivalent to calling find_reloads_toplev. | |
1992 | The code is duplicated for speed. | |
1993 | When we find a pseudo always equivalent to a constant, | |
1994 | we replace it by the constant. We must be sure, however, | |
1995 | that we don't try to replace it in the insn in which it | |
1996 | is being set. */ | |
1997 | register int regno = REGNO (recog_operand[i]); | |
1998 | if (reg_equiv_constant[regno] != 0 | |
1999 | && (set == 0 || &SET_DEST (set) != recog_operand_loc[i])) | |
2000 | substed_operand[i] = recog_operand[i] | |
2001 | = reg_equiv_constant[regno]; | |
2002 | #if 0 /* This might screw code in reload1.c to delete prior output-reload | |
2003 | that feeds this insn. */ | |
2004 | if (reg_equiv_mem[regno] != 0) | |
2005 | substed_operand[i] = recog_operand[i] | |
2006 | = reg_equiv_mem[regno]; | |
2007 | #endif | |
2008 | if (reg_equiv_address[regno] != 0) | |
2009 | { | |
2010 | /* If reg_equiv_address is not a constant address, copy it, | |
2011 | since it may be shared. */ | |
2012 | rtx address = reg_equiv_address[regno]; | |
2013 | ||
2014 | if (rtx_varies_p (address)) | |
2015 | address = copy_rtx (address); | |
2016 | ||
2017 | /* If this is an output operand, we must output a CLOBBER | |
2018 | after INSN so find_equiv_reg knows REGNO is being written. */ | |
2019 | if (constraints[i][0] == '=' | |
2020 | || constraints[i][0] == '+') | |
2021 | emit_insn_after (gen_rtx (CLOBBER, VOIDmode, recog_operand[i]), | |
2022 | insn); | |
2023 | ||
2024 | *recog_operand_loc[i] = recog_operand[i] | |
2025 | = gen_rtx (MEM, GET_MODE (recog_operand[i]), address); | |
2026 | RTX_UNCHANGING_P (recog_operand[i]) | |
2027 | = RTX_UNCHANGING_P (regno_reg_rtx[regno]); | |
2028 | find_reloads_address (GET_MODE (recog_operand[i]), | |
6dc42e49 | 2029 | /* This is no longer a pseudo register. To prevent later code |
eab89b90 RK |
2030 | XEXP (recog_operand[i], 0), |
2031 | &XEXP (recog_operand[i], 0), | |
2032 | recog_operand[i], ind_levels); | |
2033 | substed_operand[i] = recog_operand[i] = *recog_operand_loc[i]; | |
2034 | } | |
2035 | } | |
aaf9712e RS |
2036 | /* If the operand is still a register (we didn't replace it with an |
2037 | equivalent), get the preferred class to reload it into. */ | |
2038 | code = GET_CODE (recog_operand[i]); | |
2039 | preferred_class[i] | |
2040 | = ((code == REG && REGNO (recog_operand[i]) > FIRST_PSEUDO_REGISTER) | |
2041 | ? reg_preferred_class (REGNO (recog_operand[i])) : NO_REGS); | |
2042 | pref_or_nothing[i] | |
2043 | = (code == REG && REGNO (recog_operand[i]) > FIRST_PSEUDO_REGISTER | |
2044 | && reg_preferred_or_nothing (REGNO (recog_operand[i]))); | |
eab89b90 RK |
2045 | } |
2046 | ||
2047 | /* If this is simply a copy from operand 1 to operand 0, merge the | |
2048 | preferred classes for the operands. */ | |
2049 | if (set != 0 && noperands >= 2 && recog_operand[0] == SET_DEST (set) | |
2050 | && recog_operand[1] == SET_SRC (set)) | |
2051 | { | |
2052 | preferred_class[0] = preferred_class[1] | |
2053 | = reg_class_subunion[(int) preferred_class[0]][(int) preferred_class[1]]; | |
2054 | pref_or_nothing[0] |= pref_or_nothing[1]; | |
2055 | pref_or_nothing[1] |= pref_or_nothing[0]; | |
2056 | } | |
2057 | ||
2058 | /* Now see what we need for pseudo-regs that didn't get hard regs | |
2059 | or got the wrong kind of hard reg. For this, we must consider | |
2060 | all the operands together against the register constraints. */ | |
2061 | ||
2062 | best = MAX_RECOG_OPERANDS + 300; | |
2063 | ||
2064 | swapped = 0; | |
2065 | goal_alternative_swapped = 0; | |
2066 | try_swapped: | |
2067 | ||
2068 | /* The constraints are made of several alternatives. | |
2069 | Each operand's constraint looks like foo,bar,... with commas | |
2070 | separating the alternatives. The first alternatives for all | |
2071 | operands go together, the second alternatives go together, etc. | |
2072 | ||
2073 | First loop over alternatives. */ | |
2074 | ||
2075 | for (this_alternative_number = 0; | |
2076 | this_alternative_number < n_alternatives; | |
2077 | this_alternative_number++) | |
2078 | { | |
2079 | /* Loop over operands for one constraint alternative. */ | |
2080 | /* LOSERS counts those that don't fit this alternative | |
2081 | and would require loading. */ | |
2082 | int losers = 0; | |
2083 | /* BAD is set to 1 if it some operand can't fit this alternative | |
2084 | even after reloading. */ | |
2085 | int bad = 0; | |
2086 | /* REJECT is a count of how undesirable this alternative says it is | |
2087 | if any reloading is required. If the alternative matches exactly | |
2088 | then REJECT is ignored, but otherwise it gets this much | |
2089 | counted against it in addition to the reloading needed. Each | |
2090 | ? counts three times here since we want the disparaging caused by | |
2091 | a bad register class to only count 1/3 as much. */ | |
2092 | int reject = 0; | |
2093 | ||
2094 | this_earlyclobber = 0; | |
2095 | ||
2096 | for (i = 0; i < noperands; i++) | |
2097 | { | |
2098 | register char *p = constraints[i]; | |
2099 | register int win = 0; | |
2100 | /* 0 => this operand can be reloaded somehow for this alternative */ | |
2101 | int badop = 1; | |
2102 | /* 0 => this operand can be reloaded if the alternative allows regs. */ | |
2103 | int winreg = 0; | |
2104 | int c; | |
2105 | register rtx operand = recog_operand[i]; | |
2106 | int offset = 0; | |
2107 | /* Nonzero means this is a MEM that must be reloaded into a reg | |
2108 | regardless of what the constraint says. */ | |
2109 | int force_reload = 0; | |
2110 | int offmemok = 0; | |
2111 | int earlyclobber = 0; | |
2112 | ||
2113 | /* If the operand is a SUBREG, extract | |
2114 | the REG or MEM (or maybe even a constant) within. | |
2115 | (Constants can occur as a result of reg_equiv_constant.) */ | |
2116 | ||
2117 | while (GET_CODE (operand) == SUBREG) | |
2118 | { | |
2119 | offset += SUBREG_WORD (operand); | |
2120 | operand = SUBREG_REG (operand); | |
2121 | /* Force reload if this is not a register or if there may may | |
2122 | be a problem accessing the register in the outer mode. */ | |
2123 | if (GET_CODE (operand) != REG | |
2124 | #ifdef BYTE_LOADS_ZERO_EXTEND | |
2125 | /* Nonparadoxical subreg of a pseudoreg. | |
2126 | Don't to load the full width if on this machine | |
2127 | we expected the fetch to zero-extend. */ | |
2128 | || ((GET_MODE_SIZE (operand_mode[i]) | |
2129 | > GET_MODE_SIZE (GET_MODE (operand))) | |
2130 | && REGNO (operand) >= FIRST_PSEUDO_REGISTER) | |
2131 | #endif /* BYTE_LOADS_ZERO_EXTEND */ | |
2132 | /* Subreg of a hard reg which can't handle the subreg's mode | |
2133 | or which would handle that mode in the wrong number of | |
2134 | registers for subregging to work. */ | |
2135 | || (REGNO (operand) < FIRST_PSEUDO_REGISTER | |
2136 | && (! HARD_REGNO_MODE_OK (REGNO (operand), | |
2137 | operand_mode[i]) | |
2138 | || (GET_MODE_SIZE (operand_mode[i]) <= UNITS_PER_WORD | |
2139 | && (GET_MODE_SIZE (GET_MODE (operand)) | |
2140 | > UNITS_PER_WORD) | |
2141 | && ((GET_MODE_SIZE (GET_MODE (operand)) | |
2142 | / UNITS_PER_WORD) | |
2143 | != HARD_REGNO_NREGS (REGNO (operand), | |
2144 | GET_MODE (operand))))))) | |
2145 | force_reload = 1; | |
2146 | } | |
2147 | ||
2148 | this_alternative[i] = (int) NO_REGS; | |
2149 | this_alternative_win[i] = 0; | |
2150 | this_alternative_offmemok[i] = 0; | |
2151 | this_alternative_earlyclobber[i] = 0; | |
2152 | this_alternative_matches[i] = -1; | |
2153 | ||
2154 | /* An empty constraint or empty alternative | |
2155 | allows anything which matched the pattern. */ | |
2156 | if (*p == 0 || *p == ',') | |
2157 | win = 1, badop = 0; | |
2158 | ||
2159 | /* Scan this alternative's specs for this operand; | |
2160 | set WIN if the operand fits any letter in this alternative. | |
2161 | Otherwise, clear BADOP if this operand could | |
2162 | fit some letter after reloads, | |
2163 | or set WINREG if this operand could fit after reloads | |
2164 | provided the constraint allows some registers. */ | |
2165 | ||
2166 | while (*p && (c = *p++) != ',') | |
2167 | switch (c) | |
2168 | { | |
2169 | case '=': | |
2170 | modified[i] = RELOAD_WRITE; | |
2171 | break; | |
2172 | ||
2173 | case '+': | |
2174 | modified[i] = RELOAD_READ_WRITE; | |
2175 | break; | |
2176 | ||
2177 | case '*': | |
2178 | break; | |
2179 | ||
2180 | case '%': | |
2181 | commutative = i; | |
2182 | break; | |
2183 | ||
2184 | case '?': | |
2185 | reject += 3; | |
2186 | break; | |
2187 | ||
2188 | case '!': | |
2189 | reject = 300; | |
2190 | break; | |
2191 | ||
2192 | case '#': | |
2193 | /* Ignore rest of this alternative as far as | |
2194 | reloading is concerned. */ | |
2195 | while (*p && *p != ',') p++; | |
2196 | break; | |
2197 | ||
2198 | case '0': | |
2199 | case '1': | |
2200 | case '2': | |
2201 | case '3': | |
2202 | case '4': | |
2203 | c -= '0'; | |
2204 | this_alternative_matches[i] = c; | |
2205 | /* We are supposed to match a previous operand. | |
2206 | If we do, we win if that one did. | |
2207 | If we do not, count both of the operands as losers. | |
2208 | (This is too conservative, since most of the time | |
2209 | only a single reload insn will be needed to make | |
2210 | the two operands win. As a result, this alternative | |
2211 | may be rejected when it is actually desirable.) */ | |
2212 | if ((swapped && (c != commutative || i != commutative + 1)) | |
2213 | /* If we are matching as if two operands were swapped, | |
2214 | also pretend that operands_match had been computed | |
2215 | with swapped. | |
2216 | But if I is the second of those and C is the first, | |
2217 | don't exchange them, because operands_match is valid | |
2218 | only on one side of its diagonal. */ | |
2219 | ? (operands_match | |
2220 | [(c == commutative || c == commutative + 1) | |
2221 | ? 2*commutative + 1 - c : c] | |
2222 | [(i == commutative || i == commutative + 1) | |
2223 | ? 2*commutative + 1 - i : i]) | |
2224 | : operands_match[c][i]) | |
2225 | win = this_alternative_win[c]; | |
2226 | else | |
2227 | { | |
2228 | /* Operands don't match. */ | |
2229 | rtx value; | |
2230 | /* Retroactively mark the operand we had to match | |
2231 | as a loser, if it wasn't already. */ | |
2232 | if (this_alternative_win[c]) | |
2233 | losers++; | |
2234 | this_alternative_win[c] = 0; | |
2235 | if (this_alternative[c] == (int) NO_REGS) | |
2236 | bad = 1; | |
2237 | /* But count the pair only once in the total badness of | |
2238 | this alternative, if the pair can be a dummy reload. */ | |
2239 | value | |
2240 | = find_dummy_reload (recog_operand[i], recog_operand[c], | |
2241 | recog_operand_loc[i], recog_operand_loc[c], | |
2242 | this_alternative[c], -1); | |
2243 | ||
2244 | if (value != 0) | |
2245 | losers--; | |
2246 | } | |
2247 | /* This can be fixed with reloads if the operand | |
2248 | we are supposed to match can be fixed with reloads. */ | |
2249 | badop = 0; | |
2250 | this_alternative[i] = this_alternative[c]; | |
2251 | break; | |
2252 | ||
2253 | case 'p': | |
2254 | /* All necessary reloads for an address_operand | |
2255 | were handled in find_reloads_address. */ | |
2256 | this_alternative[i] = (int) ALL_REGS; | |
2257 | win = 1; | |
2258 | break; | |
2259 | ||
2260 | case 'm': | |
2261 | if (force_reload) | |
2262 | break; | |
2263 | if (GET_CODE (operand) == MEM | |
2264 | || (GET_CODE (operand) == REG | |
2265 | && REGNO (operand) >= FIRST_PSEUDO_REGISTER | |
2266 | && reg_renumber[REGNO (operand)] < 0)) | |
2267 | win = 1; | |
2268 | if (CONSTANT_P (operand)) | |
2269 | badop = 0; | |
2270 | break; | |
2271 | ||
2272 | case '<': | |
2273 | if (GET_CODE (operand) == MEM | |
2274 | && ! address_reloaded[i] | |
2275 | && (GET_CODE (XEXP (operand, 0)) == PRE_DEC | |
2276 | || GET_CODE (XEXP (operand, 0)) == POST_DEC)) | |
2277 | win = 1; | |
2278 | break; | |
2279 | ||
2280 | case '>': | |
2281 | if (GET_CODE (operand) == MEM | |
2282 | && ! address_reloaded[i] | |
2283 | && (GET_CODE (XEXP (operand, 0)) == PRE_INC | |
2284 | || GET_CODE (XEXP (operand, 0)) == POST_INC)) | |
2285 | win = 1; | |
2286 | break; | |
2287 | ||
2288 | /* Memory operand whose address is not offsettable. */ | |
2289 | case 'V': | |
2290 | if (force_reload) | |
2291 | break; | |
2292 | if (GET_CODE (operand) == MEM | |
2293 | && ! (ind_levels ? offsettable_memref_p (operand) | |
2294 | : offsettable_nonstrict_memref_p (operand)) | |
2295 | /* Certain mem addresses will become offsettable | |
2296 | after they themselves are reloaded. This is important; | |
2297 | we don't want our own handling of unoffsettables | |
2298 | to override the handling of reg_equiv_address. */ | |
2299 | && !(GET_CODE (XEXP (operand, 0)) == REG | |
2300 | && (ind_levels == 0 | |
2301 | || reg_equiv_address[REGNO (XEXP (operand, 0))] != 0))) | |
2302 | win = 1; | |
2303 | break; | |
2304 | ||
2305 | /* Memory operand whose address is offsettable. */ | |
2306 | case 'o': | |
2307 | if (force_reload) | |
2308 | break; | |
2309 | if ((GET_CODE (operand) == MEM | |
2310 | /* If IND_LEVELS, find_reloads_address won't reload a | |
2311 | pseudo that didn't get a hard reg, so we have to | |
2312 | reject that case. */ | |
2313 | && (ind_levels ? offsettable_memref_p (operand) | |
2314 | : offsettable_nonstrict_memref_p (operand))) | |
2315 | /* Certain mem addresses will become offsettable | |
2316 | after they themselves are reloaded. This is important; | |
2317 | we don't want our own handling of unoffsettables | |
2318 | to override the handling of reg_equiv_address. */ | |
2319 | || (GET_CODE (operand) == MEM | |
2320 | && GET_CODE (XEXP (operand, 0)) == REG | |
2321 | && (ind_levels == 0 | |
2322 | || reg_equiv_address[REGNO (XEXP (operand, 0))] != 0)) | |
2323 | || (GET_CODE (operand) == REG | |
2324 | && REGNO (operand) >= FIRST_PSEUDO_REGISTER | |
2325 | && reg_renumber[REGNO (operand)] < 0)) | |
2326 | win = 1; | |
2327 | if (CONSTANT_P (operand) || GET_CODE (operand) == MEM) | |
2328 | badop = 0; | |
2329 | offmemok = 1; | |
2330 | break; | |
2331 | ||
2332 | case '&': | |
2333 | /* Output operand that is stored before the need for the | |
2334 | input operands (and their index registers) is over. */ | |
2335 | earlyclobber = 1, this_earlyclobber = 1; | |
2336 | break; | |
2337 | ||
2338 | case 'E': | |
2339 | /* Match any floating double constant, but only if | |
2340 | we can examine the bits of it reliably. */ | |
2341 | if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT | |
2342 | || HOST_BITS_PER_INT != BITS_PER_WORD) | |
2343 | && GET_MODE (operand) != VOIDmode && ! flag_pretend_float) | |
2344 | break; | |
2345 | if (GET_CODE (operand) == CONST_DOUBLE) | |
2346 | win = 1; | |
2347 | break; | |
2348 | ||
2349 | case 'F': | |
2350 | if (GET_CODE (operand) == CONST_DOUBLE) | |
2351 | win = 1; | |
2352 | break; | |
2353 | ||
2354 | case 'G': | |
2355 | case 'H': | |
2356 | if (GET_CODE (operand) == CONST_DOUBLE | |
2357 | && CONST_DOUBLE_OK_FOR_LETTER_P (operand, c)) | |
2358 | win = 1; | |
2359 | break; | |
2360 | ||
2361 | case 's': | |
2362 | if (GET_CODE (operand) == CONST_INT | |
2363 | || (GET_CODE (operand) == CONST_DOUBLE | |
2364 | && GET_MODE (operand) == VOIDmode)) | |
2365 | break; | |
2366 | case 'i': | |
2367 | if (CONSTANT_P (operand) | |
2368 | #ifdef LEGITIMATE_PIC_OPERAND_P | |
2369 | && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (operand)) | |
2370 | #endif | |
2371 | ) | |
2372 | win = 1; | |
2373 | break; | |
2374 | ||
2375 | case 'n': | |
2376 | if (GET_CODE (operand) == CONST_INT | |
2377 | || (GET_CODE (operand) == CONST_DOUBLE | |
2378 | && GET_MODE (operand) == VOIDmode)) | |
2379 | win = 1; | |
2380 | break; | |
2381 | ||
2382 | case 'I': | |
2383 | case 'J': | |
2384 | case 'K': | |
2385 | case 'L': | |
2386 | case 'M': | |
2387 | case 'N': | |
2388 | case 'O': | |
2389 | case 'P': | |
2390 | if (GET_CODE (operand) == CONST_INT | |
2391 | && CONST_OK_FOR_LETTER_P (INTVAL (operand), c)) | |
2392 | win = 1; | |
2393 | break; | |
2394 | ||
2395 | case 'X': | |
2396 | win = 1; | |
2397 | break; | |
2398 | ||
2399 | case 'g': | |
2400 | if (! force_reload | |
2401 | /* A PLUS is never a valid operand, but reload can make | |
2402 | it from a register when eliminating registers. */ | |
2403 | && GET_CODE (operand) != PLUS | |
2404 | /* A SCRATCH is not a valid operand. */ | |
2405 | && GET_CODE (operand) != SCRATCH | |
2406 | #ifdef LEGITIMATE_PIC_OPERAND_P | |
2407 | && (! CONSTANT_P (operand) | |
2408 | || ! flag_pic | |
2409 | || LEGITIMATE_PIC_OPERAND_P (operand)) | |
2410 | #endif | |
2411 | && (GENERAL_REGS == ALL_REGS | |
2412 | || GET_CODE (operand) != REG | |
2413 | || (REGNO (operand) >= FIRST_PSEUDO_REGISTER | |
2414 | && reg_renumber[REGNO (operand)] < 0))) | |
2415 | win = 1; | |
2416 | /* Drop through into 'r' case */ | |
2417 | ||
2418 | case 'r': | |
2419 | this_alternative[i] | |
2420 | = (int) reg_class_subunion[this_alternative[i]][(int) GENERAL_REGS]; | |
2421 | goto reg; | |
2422 | ||
2423 | #ifdef EXTRA_CONSTRAINT | |
2424 | case 'Q': | |
2425 | case 'R': | |
2426 | case 'S': | |
2427 | case 'T': | |
2428 | case 'U': | |
2429 | if (EXTRA_CONSTRAINT (operand, c)) | |
2430 | win = 1; | |
2431 | break; | |
2432 | #endif | |
2433 | ||
2434 | default: | |
2435 | this_alternative[i] | |
2436 | = (int) reg_class_subunion[this_alternative[i]][(int) REG_CLASS_FROM_LETTER (c)]; | |
2437 | ||
2438 | reg: | |
2439 | if (GET_MODE (operand) == BLKmode) | |
2440 | break; | |
2441 | winreg = 1; | |
2442 | if (GET_CODE (operand) == REG | |
2443 | && reg_fits_class_p (operand, this_alternative[i], | |
2444 | offset, GET_MODE (recog_operand[i]))) | |
2445 | win = 1; | |
2446 | break; | |
2447 | } | |
2448 | ||
2449 | constraints[i] = p; | |
2450 | ||
2451 | /* If this operand could be handled with a reg, | |
2452 | and some reg is allowed, then this operand can be handled. */ | |
2453 | if (winreg && this_alternative[i] != (int) NO_REGS) | |
2454 | badop = 0; | |
2455 | ||
2456 | /* Record which operands fit this alternative. */ | |
2457 | this_alternative_earlyclobber[i] = earlyclobber; | |
2458 | if (win && ! force_reload) | |
2459 | this_alternative_win[i] = 1; | |
2460 | else | |
2461 | { | |
2462 | this_alternative_offmemok[i] = offmemok; | |
2463 | losers++; | |
2464 | if (badop) | |
2465 | bad = 1; | |
2466 | /* Alternative loses if it has no regs for a reg operand. */ | |
2467 | if (GET_CODE (operand) == REG | |
2468 | && this_alternative[i] == (int) NO_REGS | |
2469 | && this_alternative_matches[i] < 0) | |
2470 | bad = 1; | |
2471 | ||
2472 | /* Alternative loses if it requires a type of reload not | |
2473 | permitted for this insn. We can always reload SCRATCH | |
2474 | and objects with a REG_UNUSED note. */ | |
2475 | if (GET_CODE (operand) != SCRATCH && modified[i] != RELOAD_READ | |
2476 | && no_output_reloads | |
2477 | && ! find_reg_note (insn, REG_UNUSED, operand)) | |
2478 | bad = 1; | |
2479 | else if (modified[i] != RELOAD_WRITE && no_input_reloads) | |
2480 | bad = 1; | |
2481 | ||
2482 | /* We prefer to reload pseudos over reloading other things, | |
2483 | since such reloads may be able to be eliminated later. | |
2484 | If we are reloading a SCRATCH, we won't be generating any | |
2485 | insns, just using a register, so it is also preferred. | |
2486 | So bump REJECT in other cases. */ | |
2487 | if (GET_CODE (operand) != REG && GET_CODE (operand) != SCRATCH) | |
2488 | reject++; | |
2489 | } | |
2490 | ||
2491 | /* If this operand is a pseudo register that didn't get a hard | |
2492 | reg and this alternative accepts some register, see if the | |
2493 | class that we want is a subset of the preferred class for this | |
2494 | register. If not, but it intersects that class, use the | |
2495 | preferred class instead. If it does not intersect the preferred | |
2496 | class, show that usage of this alternative should be discouraged; | |
2497 | it will be discouraged more still if the register is `preferred | |
2498 | or nothing'. We do this because it increases the chance of | |
2499 | reusing our spill register in a later insn and avoiding a pair | |
2500 | of memory stores and loads. | |
2501 | ||
2502 | Don't bother with this if this alternative will accept this | |
2503 | operand. | |
2504 | ||
2505 | Don't do this if the preferred class has only one register | |
2506 | because we might otherwise exhaust the class. */ | |
2507 | ||
2508 | ||
2509 | if (! win && this_alternative[i] != (int) NO_REGS | |
2510 | && reg_class_size[(int) preferred_class[i]] > 1) | |
2511 | { | |
2512 | if (! reg_class_subset_p (this_alternative[i], | |
2513 | preferred_class[i])) | |
2514 | { | |
2515 | /* Since we don't have a way of forming the intersection, | |
2516 | we just do something special if the preferred class | |
2517 | is a subset of the class we have; that's the most | |
2518 | common case anyway. */ | |
2519 | if (reg_class_subset_p (preferred_class[i], | |
2520 | this_alternative[i])) | |
2521 | this_alternative[i] = (int) preferred_class[i]; | |
2522 | else | |
2523 | reject += (1 + pref_or_nothing[i]); | |
2524 | } | |
2525 | } | |
2526 | } | |
2527 | ||
2528 | /* Now see if any output operands that are marked "earlyclobber" | |
2529 | in this alternative conflict with any input operands | |
2530 | or any memory addresses. */ | |
2531 | ||
2532 | for (i = 0; i < noperands; i++) | |
2533 | if (this_alternative_earlyclobber[i] | |
2534 | && this_alternative_win[i]) | |
2535 | { | |
2536 | struct decomposition early_data; | |
2537 | int j; | |
2538 | ||
2539 | early_data = decompose (recog_operand[i]); | |
2540 | ||
2541 | if (modified[i] == RELOAD_READ) | |
2542 | { | |
2543 | if (this_insn_is_asm) | |
2544 | warning_for_asm (this_insn, | |
2545 | "`&' constraint used with input operand"); | |
2546 | else | |
2547 | abort (); | |
2548 | continue; | |
2549 | } | |
2550 | ||
2551 | if (this_alternative[i] == NO_REGS) | |
2552 | { | |
2553 | this_alternative_earlyclobber[i] = 0; | |
2554 | if (this_insn_is_asm) | |
2555 | error_for_asm (this_insn, | |
2556 | "`&' constraint used with no register class"); | |
2557 | else | |
2558 | abort (); | |
2559 | } | |
2560 | ||
2561 | for (j = 0; j < noperands; j++) | |
2562 | /* Is this an input operand or a memory ref? */ | |
2563 | if ((GET_CODE (recog_operand[j]) == MEM | |
2564 | || modified[j] != RELOAD_WRITE) | |
2565 | && j != i | |
2566 | /* Ignore things like match_operator operands. */ | |
2567 | && *constraints1[j] != 0 | |
2568 | /* Don't count an input operand that is constrained to match | |
2569 | the early clobber operand. */ | |
2570 | && ! (this_alternative_matches[j] == i | |
2571 | && rtx_equal_p (recog_operand[i], recog_operand[j])) | |
2572 | /* Is it altered by storing the earlyclobber operand? */ | |
2573 | && !immune_p (recog_operand[j], recog_operand[i], early_data)) | |
2574 | { | |
2575 | /* If the output is in a single-reg class, | |
2576 | it's costly to reload it, so reload the input instead. */ | |
2577 | if (reg_class_size[this_alternative[i]] == 1 | |
2578 | && (GET_CODE (recog_operand[j]) == REG | |
2579 | || GET_CODE (recog_operand[j]) == SUBREG)) | |
2580 | { | |
2581 | losers++; | |
2582 | this_alternative_win[j] = 0; | |
2583 | } | |
2584 | else | |
2585 | break; | |
2586 | } | |
2587 | /* If an earlyclobber operand conflicts with something, | |
2588 | it must be reloaded, so request this and count the cost. */ | |
2589 | if (j != noperands) | |
2590 | { | |
2591 | losers++; | |
2592 | this_alternative_win[i] = 0; | |
2593 | for (j = 0; j < noperands; j++) | |
2594 | if (this_alternative_matches[j] == i | |
2595 | && this_alternative_win[j]) | |
2596 | { | |
2597 | this_alternative_win[j] = 0; | |
2598 | losers++; | |
2599 | } | |
2600 | } | |
2601 | } | |
2602 | ||
2603 | /* If one alternative accepts all the operands, no reload required, | |
2604 | choose that alternative; don't consider the remaining ones. */ | |
2605 | if (losers == 0) | |
2606 | { | |
2607 | /* Unswap these so that they are never swapped at `finish'. */ | |
2608 | if (commutative >= 0) | |
2609 | { | |
2610 | recog_operand[commutative] = substed_operand[commutative]; | |
2611 | recog_operand[commutative + 1] | |
2612 | = substed_operand[commutative + 1]; | |
2613 | } | |
2614 | for (i = 0; i < noperands; i++) | |
2615 | { | |
2616 | goal_alternative_win[i] = 1; | |
2617 | goal_alternative[i] = this_alternative[i]; | |
2618 | goal_alternative_offmemok[i] = this_alternative_offmemok[i]; | |
2619 | goal_alternative_matches[i] = this_alternative_matches[i]; | |
2620 | goal_alternative_earlyclobber[i] | |
2621 | = this_alternative_earlyclobber[i]; | |
2622 | } | |
2623 | goal_alternative_number = this_alternative_number; | |
2624 | goal_alternative_swapped = swapped; | |
2625 | goal_earlyclobber = this_earlyclobber; | |
2626 | goto finish; | |
2627 | } | |
2628 | ||
2629 | /* REJECT, set by the ! and ? constraint characters and when a register | |
2630 | would be reloaded into a non-preferred class, discourages the use of | |
2631 | this alternative for a reload goal. REJECT is incremented by three | |
2632 | for each ? and one for each non-preferred class. */ | |
2633 | losers = losers * 3 + reject; | |
2634 | ||
2635 | /* If this alternative can be made to work by reloading, | |
2636 | and it needs less reloading than the others checked so far, | |
2637 | record it as the chosen goal for reloading. */ | |
2638 | if (! bad && best > losers) | |
2639 | { | |
2640 | for (i = 0; i < noperands; i++) | |
2641 | { | |
2642 | goal_alternative[i] = this_alternative[i]; | |
2643 | goal_alternative_win[i] = this_alternative_win[i]; | |
2644 | goal_alternative_offmemok[i] = this_alternative_offmemok[i]; | |
2645 | goal_alternative_matches[i] = this_alternative_matches[i]; | |
2646 | goal_alternative_earlyclobber[i] | |
2647 | = this_alternative_earlyclobber[i]; | |
2648 | } | |
2649 | goal_alternative_swapped = swapped; | |
2650 | best = losers; | |
2651 | goal_alternative_number = this_alternative_number; | |
2652 | goal_earlyclobber = this_earlyclobber; | |
2653 | } | |
2654 | } | |
2655 | ||
2656 | /* If insn is commutative (it's safe to exchange a certain pair of operands) | |
2657 | then we need to try each alternative twice, | |
2658 | the second time matching those two operands | |
2659 | as if we had exchanged them. | |
2660 | To do this, really exchange them in operands. | |
2661 | ||
2662 | If we have just tried the alternatives the second time, | |
2663 | return operands to normal and drop through. */ | |
2664 | ||
2665 | if (commutative >= 0) | |
2666 | { | |
2667 | swapped = !swapped; | |
2668 | if (swapped) | |
2669 | { | |
2670 | register enum reg_class tclass; | |
2671 | register int t; | |
2672 | ||
2673 | recog_operand[commutative] = substed_operand[commutative + 1]; | |
2674 | recog_operand[commutative + 1] = substed_operand[commutative]; | |
2675 | ||
2676 | tclass = preferred_class[commutative]; | |
2677 | preferred_class[commutative] = preferred_class[commutative + 1]; | |
2678 | preferred_class[commutative + 1] = tclass; | |
2679 | ||
2680 | t = pref_or_nothing[commutative]; | |
2681 | pref_or_nothing[commutative] = pref_or_nothing[commutative + 1]; | |
2682 | pref_or_nothing[commutative + 1] = t; | |
2683 | ||
2684 | bcopy (constraints1, constraints, noperands * sizeof (char *)); | |
2685 | goto try_swapped; | |
2686 | } | |
2687 | else | |
2688 | { | |
2689 | recog_operand[commutative] = substed_operand[commutative]; | |
2690 | recog_operand[commutative + 1] = substed_operand[commutative + 1]; | |
2691 | } | |
2692 | } | |
2693 | ||
2694 | /* The operands don't meet the constraints. | |
2695 | goal_alternative describes the alternative | |
2696 | that we could reach by reloading the fewest operands. | |
2697 | Reload so as to fit it. */ | |
2698 | ||
2699 | if (best == MAX_RECOG_OPERANDS + 300) | |
2700 | { | |
2701 | /* No alternative works with reloads?? */ | |
2702 | if (insn_code_number >= 0) | |
2703 | abort (); | |
2704 | error_for_asm (insn, "inconsistent operand constraints in an `asm'"); | |
2705 | /* Avoid further trouble with this insn. */ | |
2706 | PATTERN (insn) = gen_rtx (USE, VOIDmode, const0_rtx); | |
2707 | n_reloads = 0; | |
2708 | return; | |
2709 | } | |
2710 | ||
2711 | /* Jump to `finish' from above if all operands are valid already. | |
2712 | In that case, goal_alternative_win is all 1. */ | |
2713 | finish: | |
2714 | ||
2715 | /* Right now, for any pair of operands I and J that are required to match, | |
2716 | with I < J, | |
2717 | goal_alternative_matches[J] is I. | |
2718 | Set up goal_alternative_matched as the inverse function: | |
2719 | goal_alternative_matched[I] = J. */ | |
2720 | ||
2721 | for (i = 0; i < noperands; i++) | |
2722 | goal_alternative_matched[i] = -1; | |
2723 | ||
2724 | for (i = 0; i < noperands; i++) | |
2725 | if (! goal_alternative_win[i] | |
2726 | && goal_alternative_matches[i] >= 0) | |
2727 | goal_alternative_matched[goal_alternative_matches[i]] = i; | |
2728 | ||
2729 | /* If the best alternative is with operands 1 and 2 swapped, | |
2730 | consider them swapped before reporting the reloads. */ | |
2731 | ||
2732 | if (goal_alternative_swapped) | |
2733 | { | |
2734 | register rtx tem; | |
2735 | ||
2736 | tem = substed_operand[commutative]; | |
2737 | substed_operand[commutative] = substed_operand[commutative + 1]; | |
2738 | substed_operand[commutative + 1] = tem; | |
2739 | tem = recog_operand[commutative]; | |
2740 | recog_operand[commutative] = recog_operand[commutative + 1]; | |
2741 | recog_operand[commutative + 1] = tem; | |
2742 | } | |
2743 | ||
2744 | /* Perform whatever substitutions on the operands we are supposed | |
2745 | to make due to commutativity or replacement of registers | |
2746 | with equivalent constants or memory slots. */ | |
2747 | ||
2748 | for (i = 0; i < noperands; i++) | |
2749 | { | |
2750 | *recog_operand_loc[i] = substed_operand[i]; | |
2751 | /* While we are looping on operands, initialize this. */ | |
2752 | operand_reloadnum[i] = -1; | |
2753 | } | |
2754 | ||
2755 | /* Any constants that aren't allowed and can't be reloaded | |
2756 | into registers are here changed into memory references. */ | |
2757 | for (i = 0; i < noperands; i++) | |
2758 | if (! goal_alternative_win[i] | |
2759 | && CONSTANT_P (recog_operand[i]) | |
2760 | && (PREFERRED_RELOAD_CLASS (recog_operand[i], | |
2761 | (enum reg_class) goal_alternative[i]) | |
2762 | == NO_REGS) | |
2763 | && operand_mode[i] != VOIDmode) | |
2764 | { | |
2765 | *recog_operand_loc[i] = recog_operand[i] | |
2766 | = find_reloads_toplev (force_const_mem (operand_mode[i], | |
2767 | recog_operand[i]), | |
2768 | ind_levels, 0); | |
2769 | if (alternative_allows_memconst (constraints1[i], | |
2770 | goal_alternative_number)) | |
2771 | goal_alternative_win[i] = 1; | |
2772 | } | |
2773 | ||
2774 | /* Now record reloads for all the operands that need them. */ | |
2775 | for (i = 0; i < noperands; i++) | |
2776 | if (! goal_alternative_win[i]) | |
2777 | { | |
2778 | /* Operands that match previous ones have already been handled. */ | |
2779 | if (goal_alternative_matches[i] >= 0) | |
2780 | ; | |
2781 | /* Handle an operand with a nonoffsettable address | |
2782 | appearing where an offsettable address will do | |
2783 | by reloading the address into a base register. */ | |
2784 | else if (goal_alternative_matched[i] == -1 | |
2785 | && goal_alternative_offmemok[i] | |
2786 | && GET_CODE (recog_operand[i]) == MEM) | |
2787 | { | |
2788 | operand_reloadnum[i] | |
2789 | = push_reload (XEXP (recog_operand[i], 0), 0, | |
2790 | &XEXP (recog_operand[i], 0), 0, | |
2791 | BASE_REG_CLASS, GET_MODE (XEXP (recog_operand[i], 0)), | |
2792 | VOIDmode, 0, 0, 0); | |
2793 | reload_inc[operand_reloadnum[i]] | |
2794 | = GET_MODE_SIZE (GET_MODE (recog_operand[i])); | |
2795 | } | |
2796 | else if (goal_alternative_matched[i] == -1) | |
2797 | operand_reloadnum[i] = | |
2798 | push_reload (modified[i] != RELOAD_WRITE ? recog_operand[i] : 0, | |
2799 | modified[i] != RELOAD_READ ? recog_operand[i] : 0, | |
2800 | modified[i] != RELOAD_WRITE ? recog_operand_loc[i] : 0, | |
2801 | modified[i] != RELOAD_READ ? recog_operand_loc[i] : 0, | |
2802 | (enum reg_class) goal_alternative[i], | |
2803 | (modified[i] == RELOAD_WRITE ? VOIDmode : operand_mode[i]), | |
2804 | (modified[i] == RELOAD_READ ? VOIDmode : operand_mode[i]), | |
2805 | (insn_code_number < 0 ? 0 | |
2806 | : insn_operand_strict_low[insn_code_number][i]), | |
2807 | 0, 0); | |
2808 | /* In a matching pair of operands, one must be input only | |
2809 | and the other must be output only. | |
2810 | Pass the input operand as IN and the other as OUT. */ | |
2811 | else if (modified[i] == RELOAD_READ | |
2812 | && modified[goal_alternative_matched[i]] == RELOAD_WRITE) | |
2813 | { | |
2814 | operand_reloadnum[i] | |
2815 | = push_reload (recog_operand[i], | |
2816 | recog_operand[goal_alternative_matched[i]], | |
2817 | recog_operand_loc[i], | |
2818 | recog_operand_loc[goal_alternative_matched[i]], | |
2819 | (enum reg_class) goal_alternative[i], | |
2820 | operand_mode[i], | |
2821 | operand_mode[goal_alternative_matched[i]], | |
2822 | 0, 0, 0); | |
2823 | operand_reloadnum[goal_alternative_matched[i]] = output_reloadnum; | |
2824 | } | |
2825 | else if (modified[i] == RELOAD_WRITE | |
2826 | && modified[goal_alternative_matched[i]] == RELOAD_READ) | |
2827 | { | |
2828 | operand_reloadnum[goal_alternative_matched[i]] | |
2829 | = push_reload (recog_operand[goal_alternative_matched[i]], | |
2830 | recog_operand[i], | |
2831 | recog_operand_loc[goal_alternative_matched[i]], | |
2832 | recog_operand_loc[i], | |
2833 | (enum reg_class) goal_alternative[i], | |
2834 | operand_mode[goal_alternative_matched[i]], | |
2835 | operand_mode[i], | |
2836 | 0, 0, 0); | |
2837 | operand_reloadnum[i] = output_reloadnum; | |
2838 | } | |
2839 | else if (insn_code_number >= 0) | |
2840 | abort (); | |
2841 | else | |
2842 | { | |
2843 | error_for_asm (insn, "inconsistent operand constraints in an `asm'"); | |
2844 | /* Avoid further trouble with this insn. */ | |
2845 | PATTERN (insn) = gen_rtx (USE, VOIDmode, const0_rtx); | |
2846 | n_reloads = 0; | |
2847 | return; | |
2848 | } | |
2849 | } | |
2850 | else if (goal_alternative_matched[i] < 0 | |
2851 | && goal_alternative_matches[i] < 0 | |
2852 | && optimize) | |
2853 | { | |
2854 | rtx operand = recog_operand[i]; | |
2855 | /* For each non-matching operand that's a pseudo-register | |
2856 | that didn't get a hard register, make an optional reload. | |
2857 | This may get done even if the insn needs no reloads otherwise. */ | |
2858 | /* (It would be safe to make an optional reload for a matching pair | |
2859 | of operands, but we don't bother yet.) */ | |
2860 | while (GET_CODE (operand) == SUBREG) | |
2861 | operand = XEXP (operand, 0); | |
2862 | if (GET_CODE (operand) == REG | |
2863 | && REGNO (operand) >= FIRST_PSEUDO_REGISTER | |
2864 | && reg_renumber[REGNO (operand)] < 0 | |
2865 | && (enum reg_class) goal_alternative[i] != NO_REGS | |
2866 | /* Don't make optional output reloads for jump insns | |
2867 | (such as aobjeq on the vax). */ | |
2868 | && (modified[i] == RELOAD_READ | |
2869 | || GET_CODE (insn) != JUMP_INSN)) | |
2870 | operand_reloadnum[i] | |
2871 | = push_reload (modified[i] != RELOAD_WRITE ? recog_operand[i] : 0, | |
2872 | modified[i] != RELOAD_READ ? recog_operand[i] : 0, | |
2873 | modified[i] != RELOAD_WRITE ? recog_operand_loc[i] : 0, | |
2874 | modified[i] != RELOAD_READ ? recog_operand_loc[i] : 0, | |
2875 | (enum reg_class) goal_alternative[i], | |
2876 | (modified[i] == RELOAD_WRITE ? VOIDmode : operand_mode[i]), | |
2877 | (modified[i] == RELOAD_READ ? VOIDmode : operand_mode[i]), | |
2878 | (insn_code_number < 0 ? 0 | |
2879 | : insn_operand_strict_low[insn_code_number][i]), | |
2880 | 1, 0); | |
2881 | /* Make an optional reload for an explicit mem ref. */ | |
2882 | else if (GET_CODE (operand) == MEM | |
2883 | && (enum reg_class) goal_alternative[i] != NO_REGS | |
2884 | /* Don't make optional output reloads for jump insns | |
2885 | (such as aobjeq on the vax). */ | |
2886 | && (modified[i] == RELOAD_READ | |
2887 | || GET_CODE (insn) != JUMP_INSN)) | |
2888 | operand_reloadnum[i] | |
2889 | = push_reload (modified[i] != RELOAD_WRITE ? recog_operand[i] : 0, | |
2890 | modified[i] != RELOAD_READ ? recog_operand[i] : 0, | |
2891 | modified[i] != RELOAD_WRITE ? recog_operand_loc[i] : 0, | |
2892 | modified[i] != RELOAD_READ ? recog_operand_loc[i] : 0, | |
2893 | (enum reg_class) goal_alternative[i], | |
2894 | (modified[i] == RELOAD_WRITE ? VOIDmode : operand_mode[i]), | |
2895 | (modified[i] == RELOAD_READ ? VOIDmode : operand_mode[i]), | |
2896 | (insn_code_number < 0 ? 0 | |
2897 | : insn_operand_strict_low[insn_code_number][i]), | |
2898 | 1, 0); | |
2899 | else | |
2900 | non_reloaded_operands[n_non_reloaded_operands++] = recog_operand[i]; | |
2901 | } | |
2902 | else if (goal_alternative_matched[i] < 0 | |
2903 | && goal_alternative_matches[i] < 0) | |
2904 | non_reloaded_operands[n_non_reloaded_operands++] = recog_operand[i]; | |
2905 | ||
2906 | /* Record the values of the earlyclobber operands for the caller. */ | |
2907 | if (goal_earlyclobber) | |
2908 | for (i = 0; i < noperands; i++) | |
2909 | if (goal_alternative_earlyclobber[i]) | |
2910 | reload_earlyclobbers[n_earlyclobbers++] = recog_operand[i]; | |
2911 | ||
2912 | /* If this insn pattern contains any MATCH_DUP's, make sure that | |
2913 | they will be substituted if the operands they match are substituted. | |
2914 | Also do now any substitutions we already did on the operands. | |
2915 | ||
2916 | Don't do this if we aren't making replacements because we might be | |
2917 | propagating things allocated by frame pointer elimination into places | |
2918 | it doesn't expect. */ | |
2919 | ||
2920 | if (insn_code_number >= 0 && replace) | |
2921 | for (i = insn_n_dups[insn_code_number] - 1; i >= 0; i--) | |
2922 | { | |
2923 | int opno = recog_dup_num[i]; | |
2924 | *recog_dup_loc[i] = *recog_operand_loc[opno]; | |
2925 | if (operand_reloadnum[opno] >= 0) | |
2926 | push_replacement (recog_dup_loc[i], operand_reloadnum[opno], | |
2927 | insn_operand_mode[insn_code_number][opno]); | |
2928 | } | |
2929 | ||
2930 | #if 0 | |
2931 | /* This loses because reloading of prior insns can invalidate the equivalence | |
2932 | (or at least find_equiv_reg isn't smart enough to find it any more), | |
2933 | causing this insn to need more reload regs than it needed before. | |
2934 | It may be too late to make the reload regs available. | |
2935 | Now this optimization is done safely in choose_reload_regs. */ | |
2936 | ||
2937 | /* For each reload of a reg into some other class of reg, | |
2938 | search for an existing equivalent reg (same value now) in the right class. | |
2939 | We can use it as long as we don't need to change its contents. */ | |
2940 | for (i = 0; i < n_reloads; i++) | |
2941 | if (reload_reg_rtx[i] == 0 | |
2942 | && reload_in[i] != 0 | |
2943 | && GET_CODE (reload_in[i]) == REG | |
2944 | && reload_out[i] == 0) | |
2945 | { | |
2946 | reload_reg_rtx[i] | |
2947 | = find_equiv_reg (reload_in[i], insn, reload_reg_class[i], -1, | |
2948 | static_reload_reg_p, 0, reload_inmode[i]); | |
2949 | /* Prevent generation of insn to load the value | |
2950 | because the one we found already has the value. */ | |
2951 | if (reload_reg_rtx[i]) | |
2952 | reload_in[i] = reload_reg_rtx[i]; | |
2953 | } | |
2954 | #endif | |
2955 | ||
2956 | #else /* no REGISTER_CONSTRAINTS */ | |
2957 | int noperands; | |
2958 | int insn_code_number; | |
2959 | int goal_earlyclobber = 0; /* Always 0, to make combine_reloads happen. */ | |
2960 | register int i; | |
2961 | rtx body = PATTERN (insn); | |
2962 | ||
2963 | n_reloads = 0; | |
2964 | n_replacements = 0; | |
2965 | n_earlyclobbers = 0; | |
2966 | replace_reloads = replace; | |
2967 | this_insn = insn; | |
2968 | ||
2969 | /* Find what kind of insn this is. NOPERANDS gets number of operands. | |
2970 | Store the operand values in RECOG_OPERAND and the locations | |
2971 | of the words in the insn that point to them in RECOG_OPERAND_LOC. | |
2972 | Return if the insn needs no reload processing. */ | |
2973 | ||
2974 | switch (GET_CODE (body)) | |
2975 | { | |
2976 | case USE: | |
2977 | case CLOBBER: | |
2978 | case ASM_INPUT: | |
2979 | case ADDR_VEC: | |
2980 | case ADDR_DIFF_VEC: | |
2981 | return; | |
2982 | ||
2983 | case PARALLEL: | |
2984 | case SET: | |
2985 | noperands = asm_noperands (body); | |
2986 | if (noperands >= 0) | |
2987 | { | |
2988 | /* This insn is an `asm' with operands. | |
2989 | First, find out how many operands, and allocate space. */ | |
2990 | ||
2991 | insn_code_number = -1; | |
2992 | /* ??? This is a bug! ??? | |
2993 | Give up and delete this insn if it has too many operands. */ | |
2994 | if (noperands > MAX_RECOG_OPERANDS) | |
2995 | abort (); | |
2996 | ||
2997 | /* Now get the operand values out of the insn. */ | |
2998 | ||
2999 | decode_asm_operands (body, recog_operand, recog_operand_loc, 0, 0); | |
3000 | break; | |
3001 | } | |
3002 | ||
3003 | default: | |
3004 | /* Ordinary insn: recognize it, allocate space for operands and | |
3005 | constraints, and get them out via insn_extract. */ | |
3006 | ||
3007 | insn_code_number = recog_memoized (insn); | |
3008 | noperands = insn_n_operands[insn_code_number]; | |
3009 | insn_extract (insn); | |
3010 | } | |
3011 | ||
3012 | if (noperands == 0) | |
3013 | return; | |
3014 | ||
3015 | for (i = 0; i < noperands; i++) | |
3016 | { | |
3017 | register RTX_CODE code = GET_CODE (recog_operand[i]); | |
3018 | int is_set_dest = GET_CODE (body) == SET && (i == 0); | |
3019 | ||
3020 | if (insn_code_number >= 0) | |
3021 | if (insn_operand_address_p[insn_code_number][i]) | |
3022 | find_reloads_address (VOIDmode, 0, | |
3023 | recog_operand[i], recog_operand_loc[i], | |
3024 | recog_operand[i], ind_levels); | |
3025 | if (code == MEM) | |
3026 | find_reloads_address (GET_MODE (recog_operand[i]), | |
3027 | recog_operand_loc[i], | |
3028 | XEXP (recog_operand[i], 0), | |
3029 | &XEXP (recog_operand[i], 0), | |
3030 | recog_operand[i], ind_levels); | |
3031 | if (code == SUBREG) | |
3032 | recog_operand[i] = *recog_operand_loc[i] | |
3033 | = find_reloads_toplev (recog_operand[i], ind_levels, is_set_dest); | |
3034 | if (code == REG) | |
3035 | { | |
3036 | register int regno = REGNO (recog_operand[i]); | |
3037 | if (reg_equiv_constant[regno] != 0 && !is_set_dest) | |
3038 | recog_operand[i] = *recog_operand_loc[i] | |
3039 | = reg_equiv_constant[regno]; | |
3040 | #if 0 /* This might screw code in reload1.c to delete prior output-reload | |
3041 | that feeds this insn. */ | |
3042 | if (reg_equiv_mem[regno] != 0) | |
3043 | recog_operand[i] = *recog_operand_loc[i] | |
3044 | = reg_equiv_mem[regno]; | |
3045 | #endif | |
3046 | } | |
3047 | /* All operands are non-reloaded. */ | |
3048 | non_reloaded_operands[n_non_reloaded_operands++] = recog_operand[i]; | |
3049 | } | |
3050 | #endif /* no REGISTER_CONSTRAINTS */ | |
3051 | ||
3052 | /* Determine which part of the insn each reload is needed for, | |
3053 | based on which operand the reload is needed for. | |
3054 | Reloads of entire operands are classified as RELOAD_OTHER. | |
3055 | So are reloads for which a unique purpose is not known. */ | |
3056 | ||
3057 | for (i = 0; i < n_reloads; i++) | |
3058 | { | |
3059 | reload_when_needed[i] = RELOAD_OTHER; | |
3060 | ||
3061 | if (reload_needed_for[i] != 0 && ! reload_needed_for_multiple[i]) | |
3062 | { | |
3063 | int j; | |
3064 | int output_address = 0; | |
3065 | int input_address = 0; | |
3066 | int operand_address = 0; | |
3067 | ||
3068 | /* This reload is needed only for the address of something. | |
3069 | Determine whether it is needed for addressing an operand | |
3070 | being reloaded for input, whether it is needed for an | |
3071 | operand being reloaded for output, and whether it is needed | |
3072 | for addressing an operand that won't really be reloaded. | |
3073 | ||
3074 | Note that we know that this reload is needed in only one address, | |
3075 | but we have not yet checked for the case where that same address | |
3076 | is used in both input and output reloads. | |
3077 | The following code detects this case. */ | |
3078 | ||
3079 | for (j = 0; j < n_reloads; j++) | |
3080 | if (reload_needed_for[i] == reload_in[j] | |
3081 | || reload_needed_for[i] == reload_out[j]) | |
3082 | { | |
3083 | if (reload_optional[j]) | |
3084 | operand_address = 1; | |
3085 | else | |
3086 | { | |
3087 | if (reload_needed_for[i] == reload_in[j]) | |
3088 | input_address = 1; | |
3089 | if (reload_needed_for[i] == reload_out[j]) | |
3090 | output_address = 1; | |
3091 | } | |
3092 | } | |
3093 | /* Don't ignore memrefs without optional reloads. */ | |
3094 | for (j = 0; j < n_non_reloaded_operands; j++) | |
3095 | if (reload_needed_for[i] == non_reloaded_operands[j]) | |
3096 | operand_address = 1; | |
3097 | ||
3098 | /* If it is needed for only one of those, record which one. */ | |
3099 | ||
3100 | if (input_address && ! output_address && ! operand_address) | |
3101 | reload_when_needed[i] = RELOAD_FOR_INPUT_RELOAD_ADDRESS; | |
3102 | if (output_address && ! input_address && ! operand_address) | |
3103 | reload_when_needed[i] = RELOAD_FOR_OUTPUT_RELOAD_ADDRESS; | |
3104 | if (operand_address && ! input_address && ! output_address) | |
3105 | reload_when_needed[i] = RELOAD_FOR_OPERAND_ADDRESS; | |
3106 | ||
3107 | /* Indicate those RELOAD_OTHER reloads which, though they have | |
3108 | 0 for reload_output, still cannot overlap an output reload. */ | |
3109 | ||
3110 | if (output_address && reload_when_needed[i] == RELOAD_OTHER) | |
3111 | reload_needed_for_multiple[i] = 1; | |
3112 | } | |
3113 | } | |
3114 | ||
3115 | /* Perhaps an output reload can be combined with another | |
3116 | to reduce needs by one. */ | |
3117 | if (!goal_earlyclobber) | |
3118 | combine_reloads (); | |
3119 | } | |
3120 | ||
3121 | /* Return 1 if alternative number ALTNUM in constraint-string CONSTRAINT | |
3122 | accepts a memory operand with constant address. */ | |
3123 | ||
3124 | static int | |
3125 | alternative_allows_memconst (constraint, altnum) | |
3126 | char *constraint; | |
3127 | int altnum; | |
3128 | { | |
3129 | register int c; | |
3130 | /* Skip alternatives before the one requested. */ | |
3131 | while (altnum > 0) | |
3132 | { | |
3133 | while (*constraint++ != ','); | |
3134 | altnum--; | |
3135 | } | |
3136 | /* Scan the requested alternative for 'm' or 'o'. | |
3137 | If one of them is present, this alternative accepts memory constants. */ | |
3138 | while ((c = *constraint++) && c != ',' && c != '#') | |
3139 | if (c == 'm' || c == 'o') | |
3140 | return 1; | |
3141 | return 0; | |
3142 | } | |
3143 | \f | |
3144 | /* Scan X for memory references and scan the addresses for reloading. | |
3145 | Also checks for references to "constant" regs that we want to eliminate | |
3146 | and replaces them with the values they stand for. | |
6dc42e49 | 3147 | We may alter X destructively if it contains a reference to such. |
eab89b90 RK |
3148 | If X is just a constant reg, we return the equivalent value |
3149 | instead of X. | |
3150 | ||
3151 | IND_LEVELS says how many levels of indirect addressing this machine | |
3152 | supports. | |
3153 | ||
3154 | IS_SET_DEST is true if X is the destination of a SET, which is not | |
3155 | appropriate to be replaced by a constant. */ | |
3156 | ||
3157 | static rtx | |
3158 | find_reloads_toplev (x, ind_levels, is_set_dest) | |
3159 | rtx x; | |
3160 | int ind_levels; | |
3161 | int is_set_dest; | |
3162 | { | |
3163 | register RTX_CODE code = GET_CODE (x); | |
3164 | ||
3165 | register char *fmt = GET_RTX_FORMAT (code); | |
3166 | register int i; | |
3167 | ||
3168 | if (code == REG) | |
3169 | { | |
3170 | /* This code is duplicated for speed in find_reloads. */ | |
3171 | register int regno = REGNO (x); | |
3172 | if (reg_equiv_constant[regno] != 0 && !is_set_dest) | |
3173 | x = reg_equiv_constant[regno]; | |
3174 | #if 0 | |
3175 | /* This creates (subreg (mem...)) which would cause an unnecessary | |
3176 | reload of the mem. */ | |
3177 | else if (reg_equiv_mem[regno] != 0) | |
3178 | x = reg_equiv_mem[regno]; | |
3179 | #endif | |
3180 | else if (reg_equiv_address[regno] != 0) | |
3181 | { | |
3182 | /* If reg_equiv_address varies, it may be shared, so copy it. */ | |
3183 | rtx addr = reg_equiv_address[regno]; | |
3184 | ||
3185 | if (rtx_varies_p (addr)) | |
3186 | addr = copy_rtx (addr); | |
3187 | ||
3188 | x = gen_rtx (MEM, GET_MODE (x), addr); | |
3189 | RTX_UNCHANGING_P (x) = RTX_UNCHANGING_P (regno_reg_rtx[regno]); | |
3190 | find_reloads_address (GET_MODE (x), 0, | |
3191 | XEXP (x, 0), | |
3192 | &XEXP (x, 0), x, ind_levels); | |
3193 | } | |
3194 | return x; | |
3195 | } | |
3196 | if (code == MEM) | |
3197 | { | |
3198 | rtx tem = x; | |
3199 | find_reloads_address (GET_MODE (x), &tem, XEXP (x, 0), &XEXP (x, 0), | |
3200 | x, ind_levels); | |
3201 | return tem; | |
3202 | } | |
3203 | ||
3204 | if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == REG) | |
3205 | { | |
3206 | /* Check for SUBREG containing a REG that's equivalent to a constant. | |
3207 | If the constant has a known value, truncate it right now. | |
3208 | Similarly if we are extracting a single-word of a multi-word | |
3209 | constant. If the constant is symbolic, allow it to be substituted | |
3210 | normally. push_reload will strip the subreg later. If the | |
3211 | constant is VOIDmode, abort because we will lose the mode of | |
3212 | the register (this should never happen because one of the cases | |
3213 | above should handle it). */ | |
3214 | ||
3215 | register int regno = REGNO (SUBREG_REG (x)); | |
3216 | rtx tem; | |
3217 | ||
3218 | if (subreg_lowpart_p (x) | |
3219 | && regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 | |
3220 | && reg_equiv_constant[regno] != 0 | |
3221 | && (tem = gen_lowpart_common (GET_MODE (x), | |
3222 | reg_equiv_constant[regno])) != 0) | |
3223 | return tem; | |
3224 | ||
3225 | if (GET_MODE_BITSIZE (GET_MODE (x)) == BITS_PER_WORD | |
3226 | && regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 | |
3227 | && reg_equiv_constant[regno] != 0 | |
3228 | && (tem = operand_subword (reg_equiv_constant[regno], | |
3229 | SUBREG_WORD (x), 0, | |
3230 | GET_MODE (SUBREG_REG (x)))) != 0) | |
3231 | return tem; | |
3232 | ||
3233 | if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 | |
3234 | && reg_equiv_constant[regno] != 0 | |
3235 | && GET_MODE (reg_equiv_constant[regno]) == VOIDmode) | |
3236 | abort (); | |
3237 | ||
3238 | /* If the subreg contains a reg that will be converted to a mem, | |
3239 | convert the subreg to a narrower memref now. | |
3240 | Otherwise, we would get (subreg (mem ...) ...), | |
3241 | which would force reload of the mem. | |
3242 | ||
3243 | We also need to do this if there is an equivalent MEM that is | |
3244 | not offsettable. In that case, alter_subreg would produce an | |
3245 | invalid address on big-endian machines. | |
3246 | ||
3247 | For machines that zero-extend byte loads, we must not reload using | |
3248 | a wider mode if we have a paradoxical SUBREG. find_reloads will | |
3249 | force a reload in that case. So we should not do anything here. */ | |
3250 | ||
3251 | else if (regno >= FIRST_PSEUDO_REGISTER | |
3252 | #ifdef BYTE_LOADS_ZERO_EXTEND | |
3253 | && (GET_MODE_SIZE (GET_MODE (x)) | |
3254 | <= GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))) | |
3255 | #endif | |
3256 | && (reg_equiv_address[regno] != 0 | |
3257 | || (reg_equiv_mem[regno] != 0 | |
3258 | && ! offsettable_memref_p (reg_equiv_mem[regno])))) | |
3259 | { | |
3260 | int offset = SUBREG_WORD (x) * UNITS_PER_WORD; | |
3261 | rtx addr = (reg_equiv_address[regno] ? reg_equiv_address[regno] | |
3262 | : XEXP (reg_equiv_mem[regno], 0)); | |
3263 | #if BYTES_BIG_ENDIAN | |
3264 | int size; | |
3265 | size = GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))); | |
3266 | offset += MIN (size, UNITS_PER_WORD); | |
3267 | size = GET_MODE_SIZE (GET_MODE (x)); | |
3268 | offset -= MIN (size, UNITS_PER_WORD); | |
3269 | #endif | |
3270 | addr = plus_constant (addr, offset); | |
3271 | x = gen_rtx (MEM, GET_MODE (x), addr); | |
3272 | RTX_UNCHANGING_P (x) = RTX_UNCHANGING_P (regno_reg_rtx[regno]); | |
3273 | find_reloads_address (GET_MODE (x), 0, | |
3274 | XEXP (x, 0), | |
3275 | &XEXP (x, 0), x, ind_levels); | |
3276 | } | |
3277 | ||
3278 | } | |
3279 | ||
3280 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
3281 | { | |
3282 | if (fmt[i] == 'e') | |
3283 | XEXP (x, i) = find_reloads_toplev (XEXP (x, i), | |
3284 | ind_levels, is_set_dest); | |
3285 | } | |
3286 | return x; | |
3287 | } | |
3288 | ||
3289 | static rtx | |
3290 | make_memloc (ad, regno) | |
3291 | rtx ad; | |
3292 | int regno; | |
3293 | { | |
3294 | register int i; | |
3295 | rtx tem = reg_equiv_address[regno]; | |
3296 | for (i = 0; i < n_memlocs; i++) | |
3297 | if (rtx_equal_p (tem, XEXP (memlocs[i], 0))) | |
3298 | return memlocs[i]; | |
3299 | ||
3300 | /* If TEM might contain a pseudo, we must copy it to avoid | |
3301 | modifying it when we do the substitution for the reload. */ | |
3302 | if (rtx_varies_p (tem)) | |
3303 | tem = copy_rtx (tem); | |
3304 | ||
3305 | tem = gen_rtx (MEM, GET_MODE (ad), tem); | |
3306 | RTX_UNCHANGING_P (tem) = RTX_UNCHANGING_P (regno_reg_rtx[regno]); | |
3307 | memlocs[n_memlocs++] = tem; | |
3308 | return tem; | |
3309 | } | |
3310 | ||
3311 | /* Record all reloads needed for handling memory address AD | |
3312 | which appears in *LOC in a memory reference to mode MODE | |
3313 | which itself is found in location *MEMREFLOC. | |
3314 | Note that we take shortcuts assuming that no multi-reg machine mode | |
3315 | occurs as part of an address. | |
3316 | ||
3317 | OPERAND is the operand of the insn within which this address appears. | |
3318 | ||
3319 | IND_LEVELS says how many levels of indirect addressing this machine | |
3320 | supports. | |
3321 | ||
3322 | Value is nonzero if this address is reloaded or replaced as a whole. | |
3323 | This is interesting to the caller if the address is an autoincrement. | |
3324 | ||
3325 | Note that there is no verification that the address will be valid after | |
3326 | this routine does its work. Instead, we rely on the fact that the address | |
3327 | was valid when reload started. So we need only undo things that reload | |
3328 | could have broken. These are wrong register types, pseudos not allocated | |
3329 | to a hard register, and frame pointer elimination. */ | |
3330 | ||
3331 | static int | |
3332 | find_reloads_address (mode, memrefloc, ad, loc, operand, ind_levels) | |
3333 | enum machine_mode mode; | |
3334 | rtx *memrefloc; | |
3335 | rtx ad; | |
3336 | rtx *loc; | |
3337 | rtx operand; | |
3338 | int ind_levels; | |
3339 | { | |
3340 | register int regno; | |
3341 | rtx tem; | |
3342 | ||
3343 | /* If the address is a register, see if it is a legitimate address and | |
3344 | reload if not. We first handle the cases where we need not reload | |
3345 | or where we must reload in a non-standard way. */ | |
3346 | ||
3347 | if (GET_CODE (ad) == REG) | |
3348 | { | |
3349 | regno = REGNO (ad); | |
3350 | ||
3351 | if (reg_equiv_constant[regno] != 0 | |
3352 | && strict_memory_address_p (mode, reg_equiv_constant[regno])) | |
3353 | { | |
3354 | *loc = ad = reg_equiv_constant[regno]; | |
3355 | return 1; | |
3356 | } | |
3357 | ||
3358 | else if (reg_equiv_address[regno] != 0) | |
3359 | { | |
3360 | tem = make_memloc (ad, regno); | |
3361 | find_reloads_address (GET_MODE (tem), 0, XEXP (tem, 0), | |
3362 | &XEXP (tem, 0), operand, ind_levels); | |
3363 | push_reload (tem, 0, loc, 0, BASE_REG_CLASS, | |
3364 | GET_MODE (ad), VOIDmode, 0, 0, | |
3365 | operand); | |
3366 | return 1; | |
3367 | } | |
3368 | ||
3369 | else if (reg_equiv_mem[regno] != 0) | |
3370 | { | |
3371 | tem = XEXP (reg_equiv_mem[regno], 0); | |
3372 | ||
3373 | /* If we can't indirect any more, a pseudo must be reloaded. | |
3374 | If the pseudo's address in its MEM is a SYMBOL_REF, it | |
3375 | must be reloaded unless indirect_symref_ok. Otherwise, it | |
3376 | can be reloaded if the address is REG or REG + CONST_INT. */ | |
3377 | ||
3378 | if (ind_levels > 0 | |
3379 | && ! (GET_CODE (tem) == SYMBOL_REF && ! indirect_symref_ok) | |
3380 | && ((GET_CODE (tem) == REG | |
3381 | && REGNO (tem) < FIRST_PSEUDO_REGISTER) | |
3382 | || (GET_CODE (tem) == PLUS | |
3383 | && GET_CODE (XEXP (tem, 0)) == REG | |
3384 | && REGNO (XEXP (tem, 0)) < FIRST_PSEUDO_REGISTER | |
3385 | && GET_CODE (XEXP (tem, 1)) == CONST_INT))) | |
3386 | return 0; | |
3387 | } | |
3388 | ||
3389 | /* The only remaining case where we can avoid a reload is if this is a | |
3390 | hard register that is valid as a base register and which is not the | |
3391 | subject of a CLOBBER in this insn. */ | |
3392 | ||
3393 | else if (regno < FIRST_PSEUDO_REGISTER && REGNO_OK_FOR_BASE_P (regno) | |
3394 | && ! regno_clobbered_p (regno, this_insn)) | |
3395 | return 0; | |
3396 | ||
3397 | /* If we do not have one of the cases above, we must do the reload. */ | |
3398 | push_reload (ad, 0, loc, 0, BASE_REG_CLASS, | |
3399 | GET_MODE (ad), VOIDmode, 0, 0, operand); | |
3400 | return 1; | |
3401 | } | |
3402 | ||
3403 | if (strict_memory_address_p (mode, ad)) | |
3404 | { | |
3405 | /* The address appears valid, so reloads are not needed. | |
3406 | But the address may contain an eliminable register. | |
3407 | This can happen because a machine with indirect addressing | |
3408 | may consider a pseudo register by itself a valid address even when | |
3409 | it has failed to get a hard reg. | |
3410 | So do a tree-walk to find and eliminate all such regs. */ | |
3411 | ||
3412 | /* But first quickly dispose of a common case. */ | |
3413 | if (GET_CODE (ad) == PLUS | |
3414 | && GET_CODE (XEXP (ad, 1)) == CONST_INT | |
3415 | && GET_CODE (XEXP (ad, 0)) == REG | |
3416 | && reg_equiv_constant[REGNO (XEXP (ad, 0))] == 0) | |
3417 | return 0; | |
3418 | ||
3419 | subst_reg_equivs_changed = 0; | |
3420 | *loc = subst_reg_equivs (ad); | |
3421 | ||
3422 | if (! subst_reg_equivs_changed) | |
3423 | return 0; | |
3424 | ||
3425 | /* Check result for validity after substitution. */ | |
3426 | if (strict_memory_address_p (mode, ad)) | |
3427 | return 0; | |
3428 | } | |
3429 | ||
3430 | /* The address is not valid. We have to figure out why. One possibility | |
3431 | is that it is itself a MEM. This can happen when the frame pointer is | |
3432 | being eliminated, a pseudo is not allocated to a hard register, and the | |
3433 | offset between the frame and stack pointers is not its initial value. | |
d45cf215 | 3434 | In that case the pseudo will have been replaced by a MEM referring to |
eab89b90 RK |
3435 | the stack pointer. */ |
3436 | if (GET_CODE (ad) == MEM) | |
3437 | { | |
3438 | /* First ensure that the address in this MEM is valid. Then, unless | |
3439 | indirect addresses are valid, reload the MEM into a register. */ | |
3440 | tem = ad; | |
3441 | find_reloads_address (GET_MODE (ad), &tem, XEXP (ad, 0), &XEXP (ad, 0), | |
3442 | operand, ind_levels == 0 ? 0 : ind_levels - 1); | |
3443 | /* Check similar cases as for indirect addresses as above except | |
3444 | that we can allow pseudos and a MEM since they should have been | |
3445 | taken care of above. */ | |
3446 | ||
3447 | if (ind_levels == 0 | |
3448 | || (GET_CODE (XEXP (tem, 0)) == SYMBOL_REF && ! indirect_symref_ok) | |
3449 | || GET_CODE (XEXP (tem, 0)) == MEM | |
3450 | || ! (GET_CODE (XEXP (tem, 0)) == REG | |
3451 | || (GET_CODE (XEXP (tem, 0)) == PLUS | |
3452 | && GET_CODE (XEXP (XEXP (tem, 0), 0)) == REG | |
3453 | && GET_CODE (XEXP (XEXP (tem, 0), 1)) == CONST_INT))) | |
3454 | { | |
3455 | /* Must use TEM here, not AD, since it is the one that will | |
3456 | have any subexpressions reloaded, if needed. */ | |
3457 | push_reload (tem, 0, loc, 0, | |
3458 | BASE_REG_CLASS, GET_MODE (tem), VOIDmode, 0, | |
3459 | 0, operand); | |
3460 | return 1; | |
3461 | } | |
3462 | else | |
3463 | return 0; | |
3464 | } | |
3465 | ||
3466 | /* If we have address of a stack slot but it's not valid | |
3467 | (displacement is too large), compute the sum in a register. */ | |
3468 | else if (GET_CODE (ad) == PLUS | |
3469 | && (XEXP (ad, 0) == frame_pointer_rtx | |
3470 | #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM | |
3471 | || XEXP (ad, 0) == arg_pointer_rtx | |
3472 | #endif | |
3473 | || XEXP (ad, 0) == stack_pointer_rtx) | |
3474 | && GET_CODE (XEXP (ad, 1)) == CONST_INT) | |
3475 | { | |
3476 | /* Unshare the MEM rtx so we can safely alter it. */ | |
3477 | if (memrefloc) | |
3478 | { | |
3479 | rtx oldref = *memrefloc; | |
3480 | *memrefloc = copy_rtx (*memrefloc); | |
3481 | loc = &XEXP (*memrefloc, 0); | |
3482 | if (operand == oldref) | |
3483 | operand = *memrefloc; | |
3484 | } | |
3485 | if (double_reg_address_ok) | |
3486 | { | |
3487 | /* Unshare the sum as well. */ | |
3488 | *loc = ad = copy_rtx (ad); | |
3489 | /* Reload the displacement into an index reg. | |
3490 | We assume the frame pointer or arg pointer is a base reg. */ | |
3491 | find_reloads_address_part (XEXP (ad, 1), &XEXP (ad, 1), | |
3492 | INDEX_REG_CLASS, GET_MODE (ad), operand, | |
3493 | ind_levels); | |
3494 | } | |
3495 | else | |
3496 | { | |
3497 | /* If the sum of two regs is not necessarily valid, | |
3498 | reload the sum into a base reg. | |
3499 | That will at least work. */ | |
3500 | find_reloads_address_part (ad, loc, BASE_REG_CLASS, Pmode, | |
3501 | operand, ind_levels); | |
3502 | } | |
3503 | return 1; | |
3504 | } | |
3505 | ||
3506 | /* If we have an indexed stack slot, there are three possible reasons why | |
3507 | it might be invalid: The index might need to be reloaded, the address | |
3508 | might have been made by frame pointer elimination and hence have a | |
3509 | constant out of range, or both reasons might apply. | |
3510 | ||
3511 | We can easily check for an index needing reload, but even if that is the | |
3512 | case, we might also have an invalid constant. To avoid making the | |
3513 | conservative assumption and requiring two reloads, we see if this address | |
3514 | is valid when not interpreted strictly. If it is, the only problem is | |
3515 | that the index needs a reload and find_reloads_address_1 will take care | |
3516 | of it. | |
3517 | ||
3518 | There is still a case when we might generate an extra reload, | |
3519 | however. In certain cases eliminate_regs will return a MEM for a REG | |
3520 | (see the code there for details). In those cases, memory_address_p | |
3521 | applied to our address will return 0 so we will think that our offset | |
3522 | must be too large. But it might indeed be valid and the only problem | |
3523 | is that a MEM is present where a REG should be. This case should be | |
3524 | very rare and there doesn't seem to be any way to avoid it. | |
3525 | ||
3526 | If we decide to do something here, it must be that | |
3527 | `double_reg_address_ok' is true and that this address rtl was made by | |
3528 | eliminate_regs. We generate a reload of the fp/sp/ap + constant and | |
3529 | rework the sum so that the reload register will be added to the index. | |
3530 | This is safe because we know the address isn't shared. | |
3531 | ||
3532 | We check for fp/ap/sp as both the first and second operand of the | |
3533 | innermost PLUS. */ | |
3534 | ||
3535 | else if (GET_CODE (ad) == PLUS && GET_CODE (XEXP (ad, 1)) == CONST_INT | |
3536 | && GET_CODE (XEXP (ad, 0)) == PLUS | |
3537 | && (XEXP (XEXP (ad, 0), 0) == frame_pointer_rtx | |
3538 | #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM | |
3539 | || XEXP (XEXP (ad, 0), 0) == arg_pointer_rtx | |
3540 | #endif | |
3541 | || XEXP (XEXP (ad, 0), 0) == stack_pointer_rtx) | |
3542 | && ! memory_address_p (mode, ad)) | |
3543 | { | |
3544 | *loc = ad = gen_rtx (PLUS, GET_MODE (ad), | |
3545 | plus_constant (XEXP (XEXP (ad, 0), 0), | |
3546 | INTVAL (XEXP (ad, 1))), | |
3547 | XEXP (XEXP (ad, 0), 1)); | |
3548 | find_reloads_address_part (XEXP (ad, 0), &XEXP (ad, 0), BASE_REG_CLASS, | |
3549 | GET_MODE (ad), operand, ind_levels); | |
3550 | find_reloads_address_1 (XEXP (ad, 1), 1, &XEXP (ad, 1), operand, 0); | |
3551 | ||
3552 | return 1; | |
3553 | } | |
3554 | ||
3555 | else if (GET_CODE (ad) == PLUS && GET_CODE (XEXP (ad, 1)) == CONST_INT | |
3556 | && GET_CODE (XEXP (ad, 0)) == PLUS | |
3557 | && (XEXP (XEXP (ad, 0), 1) == frame_pointer_rtx | |
3558 | #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM | |
3559 | || XEXP (XEXP (ad, 0), 1) == arg_pointer_rtx | |
3560 | #endif | |
3561 | || XEXP (XEXP (ad, 0), 1) == stack_pointer_rtx) | |
3562 | && ! memory_address_p (mode, ad)) | |
3563 | { | |
3564 | *loc = ad = gen_rtx (PLUS, GET_MODE (ad), | |
3565 | plus_constant (XEXP (XEXP (ad, 0), 1), | |
3566 | INTVAL (XEXP (ad, 1))), | |
3567 | XEXP (XEXP (ad, 0), 0)); | |
3568 | find_reloads_address_part (XEXP (ad, 0), &XEXP (ad, 0), BASE_REG_CLASS, | |
3569 | GET_MODE (ad), operand, ind_levels); | |
3570 | find_reloads_address_1 (XEXP (ad, 1), 1, &XEXP (ad, 1), operand, 0); | |
3571 | ||
3572 | return 1; | |
3573 | } | |
3574 | ||
3575 | /* See if address becomes valid when an eliminable register | |
3576 | in a sum is replaced. */ | |
3577 | ||
3578 | tem = ad; | |
3579 | if (GET_CODE (ad) == PLUS) | |
3580 | tem = subst_indexed_address (ad); | |
3581 | if (tem != ad && strict_memory_address_p (mode, tem)) | |
3582 | { | |
3583 | /* Ok, we win that way. Replace any additional eliminable | |
3584 | registers. */ | |
3585 | ||
3586 | subst_reg_equivs_changed = 0; | |
3587 | tem = subst_reg_equivs (tem); | |
3588 | ||
3589 | /* Make sure that didn't make the address invalid again. */ | |
3590 | ||
3591 | if (! subst_reg_equivs_changed || strict_memory_address_p (mode, tem)) | |
3592 | { | |
3593 | *loc = tem; | |
3594 | return 0; | |
3595 | } | |
3596 | } | |
3597 | ||
3598 | /* If constants aren't valid addresses, reload the constant address | |
3599 | into a register. */ | |
3600 | if (CONSTANT_ADDRESS_P (ad) && ! strict_memory_address_p (mode, ad)) | |
3601 | { | |
3602 | /* If AD is in address in the constant pool, the MEM rtx may be shared. | |
3603 | Unshare it so we can safely alter it. */ | |
3604 | if (memrefloc && GET_CODE (ad) == SYMBOL_REF | |
3605 | && CONSTANT_POOL_ADDRESS_P (ad)) | |
3606 | { | |
3607 | rtx oldref = *memrefloc; | |
3608 | *memrefloc = copy_rtx (*memrefloc); | |
3609 | loc = &XEXP (*memrefloc, 0); | |
3610 | if (operand == oldref) | |
3611 | operand = *memrefloc; | |
3612 | } | |
3613 | ||
3614 | find_reloads_address_part (ad, loc, BASE_REG_CLASS, Pmode, operand, | |
3615 | ind_levels); | |
3616 | return 1; | |
3617 | } | |
3618 | ||
3619 | return find_reloads_address_1 (ad, 0, loc, operand, ind_levels); | |
3620 | } | |
3621 | \f | |
3622 | /* Find all pseudo regs appearing in AD | |
3623 | that are eliminable in favor of equivalent values | |
3624 | and do not have hard regs; replace them by their equivalents. */ | |
3625 | ||
3626 | static rtx | |
3627 | subst_reg_equivs (ad) | |
3628 | rtx ad; | |
3629 | { | |
3630 | register RTX_CODE code = GET_CODE (ad); | |
3631 | register int i; | |
3632 | register char *fmt; | |
3633 | ||
3634 | switch (code) | |
3635 | { | |
3636 | case HIGH: | |
3637 | case CONST_INT: | |
3638 | case CONST: | |
3639 | case CONST_DOUBLE: | |
3640 | case SYMBOL_REF: | |
3641 | case LABEL_REF: | |
3642 | case PC: | |
3643 | case CC0: | |
3644 | return ad; | |
3645 | ||
3646 | case REG: | |
3647 | { | |
3648 | register int regno = REGNO (ad); | |
3649 | ||
3650 | if (reg_equiv_constant[regno] != 0) | |
3651 | { | |
3652 | subst_reg_equivs_changed = 1; | |
3653 | return reg_equiv_constant[regno]; | |
3654 | } | |
3655 | } | |
3656 | return ad; | |
3657 | ||
3658 | case PLUS: | |
3659 | /* Quickly dispose of a common case. */ | |
3660 | if (XEXP (ad, 0) == frame_pointer_rtx | |
3661 | && GET_CODE (XEXP (ad, 1)) == CONST_INT) | |
3662 | return ad; | |
3663 | } | |
3664 | ||
3665 | fmt = GET_RTX_FORMAT (code); | |
3666 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
3667 | if (fmt[i] == 'e') | |
3668 | XEXP (ad, i) = subst_reg_equivs (XEXP (ad, i)); | |
3669 | return ad; | |
3670 | } | |
3671 | \f | |
3672 | /* Compute the sum of X and Y, making canonicalizations assumed in an | |
3673 | address, namely: sum constant integers, surround the sum of two | |
3674 | constants with a CONST, put the constant as the second operand, and | |
3675 | group the constant on the outermost sum. | |
3676 | ||
3677 | This routine assumes both inputs are already in canonical form. */ | |
3678 | ||
3679 | rtx | |
3680 | form_sum (x, y) | |
3681 | rtx x, y; | |
3682 | { | |
3683 | rtx tem; | |
3684 | ||
3685 | if (GET_CODE (x) == CONST_INT) | |
3686 | return plus_constant (y, INTVAL (x)); | |
3687 | else if (GET_CODE (y) == CONST_INT) | |
3688 | return plus_constant (x, INTVAL (y)); | |
3689 | else if (CONSTANT_P (x)) | |
3690 | tem = x, x = y, y = tem; | |
3691 | ||
3692 | if (GET_CODE (x) == PLUS && CONSTANT_P (XEXP (x, 1))) | |
3693 | return form_sum (XEXP (x, 0), form_sum (XEXP (x, 1), y)); | |
3694 | ||
3695 | /* Note that if the operands of Y are specified in the opposite | |
3696 | order in the recursive calls below, infinite recursion will occur. */ | |
3697 | if (GET_CODE (y) == PLUS && CONSTANT_P (XEXP (y, 1))) | |
3698 | return form_sum (form_sum (x, XEXP (y, 0)), XEXP (y, 1)); | |
3699 | ||
3700 | /* If both constant, encapsulate sum. Otherwise, just form sum. A | |
3701 | constant will have been placed second. */ | |
3702 | if (CONSTANT_P (x) && CONSTANT_P (y)) | |
3703 | { | |
3704 | if (GET_CODE (x) == CONST) | |
3705 | x = XEXP (x, 0); | |
3706 | if (GET_CODE (y) == CONST) | |
3707 | y = XEXP (y, 0); | |
3708 | ||
3709 | return gen_rtx (CONST, VOIDmode, gen_rtx (PLUS, Pmode, x, y)); | |
3710 | } | |
3711 | ||
3712 | return gen_rtx (PLUS, Pmode, x, y); | |
3713 | } | |
3714 | \f | |
3715 | /* If ADDR is a sum containing a pseudo register that should be | |
3716 | replaced with a constant (from reg_equiv_constant), | |
3717 | return the result of doing so, and also apply the associative | |
3718 | law so that the result is more likely to be a valid address. | |
3719 | (But it is not guaranteed to be one.) | |
3720 | ||
3721 | Note that at most one register is replaced, even if more are | |
3722 | replaceable. Also, we try to put the result into a canonical form | |
3723 | so it is more likely to be a valid address. | |
3724 | ||
3725 | In all other cases, return ADDR. */ | |
3726 | ||
3727 | static rtx | |
3728 | subst_indexed_address (addr) | |
3729 | rtx addr; | |
3730 | { | |
3731 | rtx op0 = 0, op1 = 0, op2 = 0; | |
3732 | rtx tem; | |
3733 | int regno; | |
3734 | ||
3735 | if (GET_CODE (addr) == PLUS) | |
3736 | { | |
3737 | /* Try to find a register to replace. */ | |
3738 | op0 = XEXP (addr, 0), op1 = XEXP (addr, 1), op2 = 0; | |
3739 | if (GET_CODE (op0) == REG | |
3740 | && (regno = REGNO (op0)) >= FIRST_PSEUDO_REGISTER | |
3741 | && reg_renumber[regno] < 0 | |
3742 | && reg_equiv_constant[regno] != 0) | |
3743 | op0 = reg_equiv_constant[regno]; | |
3744 | else if (GET_CODE (op1) == REG | |
3745 | && (regno = REGNO (op1)) >= FIRST_PSEUDO_REGISTER | |
3746 | && reg_renumber[regno] < 0 | |
3747 | && reg_equiv_constant[regno] != 0) | |
3748 | op1 = reg_equiv_constant[regno]; | |
3749 | else if (GET_CODE (op0) == PLUS | |
3750 | && (tem = subst_indexed_address (op0)) != op0) | |
3751 | op0 = tem; | |
3752 | else if (GET_CODE (op1) == PLUS | |
3753 | && (tem = subst_indexed_address (op1)) != op1) | |
3754 | op1 = tem; | |
3755 | else | |
3756 | return addr; | |
3757 | ||
3758 | /* Pick out up to three things to add. */ | |
3759 | if (GET_CODE (op1) == PLUS) | |
3760 | op2 = XEXP (op1, 1), op1 = XEXP (op1, 0); | |
3761 | else if (GET_CODE (op0) == PLUS) | |
3762 | op2 = op1, op1 = XEXP (op0, 1), op0 = XEXP (op0, 0); | |
3763 | ||
3764 | /* Compute the sum. */ | |
3765 | if (op2 != 0) | |
3766 | op1 = form_sum (op1, op2); | |
3767 | if (op1 != 0) | |
3768 | op0 = form_sum (op0, op1); | |
3769 | ||
3770 | return op0; | |
3771 | } | |
3772 | return addr; | |
3773 | } | |
3774 | \f | |
3775 | /* Record the pseudo registers we must reload into hard registers | |
3776 | in a subexpression of a would-be memory address, X. | |
3777 | (This function is not called if the address we find is strictly valid.) | |
3778 | CONTEXT = 1 means we are considering regs as index regs, | |
3779 | = 0 means we are considering them as base regs. | |
3780 | ||
3781 | OPERAND is the operand of the insn within which this address appears. | |
3782 | ||
3783 | IND_LEVELS says how many levels of indirect addressing are | |
3784 | supported at this point in the address. | |
3785 | ||
3786 | We return nonzero if X, as a whole, is reloaded or replaced. */ | |
3787 | ||
3788 | /* Note that we take shortcuts assuming that no multi-reg machine mode | |
3789 | occurs as part of an address. | |
3790 | Also, this is not fully machine-customizable; it works for machines | |
3791 | such as vaxes and 68000's and 32000's, but other possible machines | |
3792 | could have addressing modes that this does not handle right. */ | |
3793 | ||
3794 | static int | |
3795 | find_reloads_address_1 (x, context, loc, operand, ind_levels) | |
3796 | rtx x; | |
3797 | int context; | |
3798 | rtx *loc; | |
3799 | rtx operand; | |
3800 | int ind_levels; | |
3801 | { | |
3802 | register RTX_CODE code = GET_CODE (x); | |
3803 | ||
3804 | if (code == PLUS) | |
3805 | { | |
3806 | register rtx op0 = XEXP (x, 0); | |
3807 | register rtx op1 = XEXP (x, 1); | |
3808 | register RTX_CODE code0 = GET_CODE (op0); | |
3809 | register RTX_CODE code1 = GET_CODE (op1); | |
3810 | if (code0 == MULT || code0 == SIGN_EXTEND || code1 == MEM) | |
3811 | { | |
3812 | find_reloads_address_1 (op0, 1, &XEXP (x, 0), operand, ind_levels); | |
3813 | find_reloads_address_1 (op1, 0, &XEXP (x, 1), operand, ind_levels); | |
3814 | } | |
3815 | else if (code1 == MULT || code1 == SIGN_EXTEND || code0 == MEM) | |
3816 | { | |
3817 | find_reloads_address_1 (op0, 0, &XEXP (x, 0), operand, ind_levels); | |
3818 | find_reloads_address_1 (op1, 1, &XEXP (x, 1), operand, ind_levels); | |
3819 | } | |
3820 | else if (code0 == CONST_INT || code0 == CONST | |
3821 | || code0 == SYMBOL_REF || code0 == LABEL_REF) | |
3822 | { | |
3823 | find_reloads_address_1 (op1, 0, &XEXP (x, 1), operand, ind_levels); | |
3824 | } | |
3825 | else if (code1 == CONST_INT || code1 == CONST | |
3826 | || code1 == SYMBOL_REF || code1 == LABEL_REF) | |
3827 | { | |
3828 | find_reloads_address_1 (op0, 0, &XEXP (x, 0), operand, ind_levels); | |
3829 | } | |
3830 | else if (code0 == REG && code1 == REG) | |
3831 | { | |
3832 | if (REG_OK_FOR_INDEX_P (op0) | |
3833 | && REG_OK_FOR_BASE_P (op1)) | |
3834 | return 0; | |
3835 | else if (REG_OK_FOR_INDEX_P (op1) | |
3836 | && REG_OK_FOR_BASE_P (op0)) | |
3837 | return 0; | |
3838 | else if (REG_OK_FOR_BASE_P (op1)) | |
3839 | find_reloads_address_1 (op0, 1, &XEXP (x, 0), operand, ind_levels); | |
3840 | else if (REG_OK_FOR_BASE_P (op0)) | |
3841 | find_reloads_address_1 (op1, 1, &XEXP (x, 1), operand, ind_levels); | |
3842 | else if (REG_OK_FOR_INDEX_P (op1)) | |
3843 | find_reloads_address_1 (op0, 0, &XEXP (x, 0), operand, ind_levels); | |
3844 | else if (REG_OK_FOR_INDEX_P (op0)) | |
3845 | find_reloads_address_1 (op1, 0, &XEXP (x, 1), operand, ind_levels); | |
3846 | else | |
3847 | { | |
3848 | find_reloads_address_1 (op0, 1, &XEXP (x, 0), operand, | |
3849 | ind_levels); | |
3850 | find_reloads_address_1 (op1, 0, &XEXP (x, 1), operand, | |
3851 | ind_levels); | |
3852 | } | |
3853 | } | |
3854 | else if (code0 == REG) | |
3855 | { | |
3856 | find_reloads_address_1 (op0, 1, &XEXP (x, 0), operand, ind_levels); | |
3857 | find_reloads_address_1 (op1, 0, &XEXP (x, 1), operand, ind_levels); | |
3858 | } | |
3859 | else if (code1 == REG) | |
3860 | { | |
3861 | find_reloads_address_1 (op1, 1, &XEXP (x, 1), operand, ind_levels); | |
3862 | find_reloads_address_1 (op0, 0, &XEXP (x, 0), operand, ind_levels); | |
3863 | } | |
3864 | } | |
3865 | else if (code == POST_INC || code == POST_DEC | |
3866 | || code == PRE_INC || code == PRE_DEC) | |
3867 | { | |
3868 | if (GET_CODE (XEXP (x, 0)) == REG) | |
3869 | { | |
3870 | register int regno = REGNO (XEXP (x, 0)); | |
3871 | int value = 0; | |
3872 | rtx x_orig = x; | |
3873 | ||
3874 | /* A register that is incremented cannot be constant! */ | |
3875 | if (regno >= FIRST_PSEUDO_REGISTER | |
3876 | && reg_equiv_constant[regno] != 0) | |
3877 | abort (); | |
3878 | ||
3879 | /* Handle a register that is equivalent to a memory location | |
3880 | which cannot be addressed directly. */ | |
3881 | if (reg_equiv_address[regno] != 0) | |
3882 | { | |
3883 | rtx tem = make_memloc (XEXP (x, 0), regno); | |
3884 | /* First reload the memory location's address. */ | |
3885 | find_reloads_address (GET_MODE (tem), 0, XEXP (tem, 0), | |
3886 | &XEXP (tem, 0), operand, ind_levels); | |
3887 | /* Put this inside a new increment-expression. */ | |
3888 | x = gen_rtx (GET_CODE (x), GET_MODE (x), tem); | |
3889 | /* Proceed to reload that, as if it contained a register. */ | |
3890 | } | |
3891 | ||
3892 | /* If we have a hard register that is ok as an index, | |
3893 | don't make a reload. If an autoincrement of a nice register | |
3894 | isn't "valid", it must be that no autoincrement is "valid". | |
3895 | If that is true and something made an autoincrement anyway, | |
3896 | this must be a special context where one is allowed. | |
3897 | (For example, a "push" instruction.) | |
3898 | We can't improve this address, so leave it alone. */ | |
3899 | ||
3900 | /* Otherwise, reload the autoincrement into a suitable hard reg | |
3901 | and record how much to increment by. */ | |
3902 | ||
3903 | if (reg_renumber[regno] >= 0) | |
3904 | regno = reg_renumber[regno]; | |
3905 | if ((regno >= FIRST_PSEUDO_REGISTER | |
3906 | || !(context ? REGNO_OK_FOR_INDEX_P (regno) | |
3907 | : REGNO_OK_FOR_BASE_P (regno)))) | |
3908 | { | |
3909 | register rtx link; | |
3910 | ||
3911 | int reloadnum | |
3912 | = push_reload (x, 0, loc, 0, | |
3913 | context ? INDEX_REG_CLASS : BASE_REG_CLASS, | |
3914 | GET_MODE (x), GET_MODE (x), VOIDmode, 0, operand); | |
3915 | reload_inc[reloadnum] | |
3916 | = find_inc_amount (PATTERN (this_insn), XEXP (x_orig, 0)); | |
3917 | ||
3918 | value = 1; | |
3919 | ||
3920 | #ifdef AUTO_INC_DEC | |
3921 | /* Update the REG_INC notes. */ | |
3922 | ||
3923 | for (link = REG_NOTES (this_insn); | |
3924 | link; link = XEXP (link, 1)) | |
3925 | if (REG_NOTE_KIND (link) == REG_INC | |
3926 | && REGNO (XEXP (link, 0)) == REGNO (XEXP (x_orig, 0))) | |
3927 | push_replacement (&XEXP (link, 0), reloadnum, VOIDmode); | |
3928 | #endif | |
3929 | } | |
3930 | return value; | |
3931 | } | |
3932 | else if (GET_CODE (XEXP (x, 0)) == MEM) | |
3933 | { | |
3934 | /* This is probably the result of a substitution, by eliminate_regs, | |
3935 | of an equivalent address for a pseudo that was not allocated to a | |
3936 | hard register. Verify that the specified address is valid and | |
3937 | reload it into a register. */ | |
3938 | rtx tem = XEXP (x, 0); | |
3939 | register rtx link; | |
3940 | int reloadnum; | |
3941 | ||
3942 | /* Since we know we are going to reload this item, don't decrement | |
3943 | for the indirection level. | |
3944 | ||
3945 | Note that this is actually conservative: it would be slightly | |
3946 | more efficient to use the value of SPILL_INDIRECT_LEVELS from | |
3947 | reload1.c here. */ | |
3948 | find_reloads_address (GET_MODE (x), &XEXP (x, 0), | |
3949 | XEXP (XEXP (x, 0), 0), &XEXP (XEXP (x, 0), 0), | |
3950 | operand, ind_levels); | |
3951 | ||
3952 | reloadnum = push_reload (x, 0, loc, 0, | |
3953 | context ? INDEX_REG_CLASS : BASE_REG_CLASS, | |
3954 | GET_MODE (x), VOIDmode, 0, 0, operand); | |
3955 | reload_inc[reloadnum] | |
3956 | = find_inc_amount (PATTERN (this_insn), XEXP (x, 0)); | |
3957 | ||
3958 | link = FIND_REG_INC_NOTE (this_insn, tem); | |
3959 | if (link != 0) | |
3960 | push_replacement (&XEXP (link, 0), reloadnum, VOIDmode); | |
3961 | ||
3962 | return 1; | |
3963 | } | |
3964 | } | |
3965 | else if (code == MEM) | |
3966 | { | |
3967 | /* This is probably the result of a substitution, by eliminate_regs, | |
3968 | of an equivalent address for a pseudo that was not allocated to a | |
3969 | hard register. Verify that the specified address is valid and reload | |
3970 | it into a register. | |
3971 | ||
3972 | Since we know we are going to reload this item, don't decrement | |
3973 | for the indirection level. | |
3974 | ||
3975 | Note that this is actually conservative: it would be slightly more | |
3976 | efficient to use the value of SPILL_INDIRECT_LEVELS from | |
3977 | reload1.c here. */ | |
3978 | ||
3979 | find_reloads_address (GET_MODE (x), loc, XEXP (x, 0), &XEXP (x, 0), | |
3980 | operand, ind_levels); | |
3981 | ||
3982 | push_reload (*loc, 0, loc, 0, | |
3983 | context ? INDEX_REG_CLASS : BASE_REG_CLASS, | |
3984 | GET_MODE (x), VOIDmode, 0, 0, operand); | |
3985 | return 1; | |
3986 | } | |
3987 | else if (code == REG) | |
3988 | { | |
3989 | register int regno = REGNO (x); | |
3990 | ||
3991 | if (reg_equiv_constant[regno] != 0) | |
3992 | { | |
3993 | push_reload (reg_equiv_constant[regno], 0, loc, 0, | |
3994 | context ? INDEX_REG_CLASS : BASE_REG_CLASS, | |
3995 | GET_MODE (x), VOIDmode, 0, 0, operand); | |
3996 | return 1; | |
3997 | } | |
3998 | ||
3999 | #if 0 /* This might screw code in reload1.c to delete prior output-reload | |
4000 | that feeds this insn. */ | |
4001 | if (reg_equiv_mem[regno] != 0) | |
4002 | { | |
4003 | push_reload (reg_equiv_mem[regno], 0, loc, 0, | |
4004 | context ? INDEX_REG_CLASS : BASE_REG_CLASS, | |
4005 | GET_MODE (x), VOIDmode, 0, 0, operand); | |
4006 | return 1; | |
4007 | } | |
4008 | #endif | |
4009 | if (reg_equiv_address[regno] != 0) | |
4010 | { | |
4011 | x = make_memloc (x, regno); | |
4012 | find_reloads_address (GET_MODE (x), 0, XEXP (x, 0), &XEXP (x, 0), | |
4013 | operand, ind_levels); | |
4014 | } | |
4015 | ||
4016 | if (reg_renumber[regno] >= 0) | |
4017 | regno = reg_renumber[regno]; | |
4018 | if ((regno >= FIRST_PSEUDO_REGISTER | |
4019 | || !(context ? REGNO_OK_FOR_INDEX_P (regno) | |
4020 | : REGNO_OK_FOR_BASE_P (regno)))) | |
4021 | { | |
4022 | push_reload (x, 0, loc, 0, | |
4023 | context ? INDEX_REG_CLASS : BASE_REG_CLASS, | |
4024 | GET_MODE (x), VOIDmode, 0, 0, operand); | |
4025 | return 1; | |
4026 | } | |
4027 | ||
4028 | /* If a register appearing in an address is the subject of a CLOBBER | |
4029 | in this insn, reload it into some other register to be safe. | |
4030 | The CLOBBER is supposed to make the register unavailable | |
4031 | from before this insn to after it. */ | |
4032 | if (regno_clobbered_p (regno, this_insn)) | |
4033 | { | |
4034 | push_reload (x, 0, loc, 0, | |
4035 | context ? INDEX_REG_CLASS : BASE_REG_CLASS, | |
4036 | GET_MODE (x), VOIDmode, 0, 0, operand); | |
4037 | return 1; | |
4038 | } | |
4039 | } | |
4040 | else | |
4041 | { | |
4042 | register char *fmt = GET_RTX_FORMAT (code); | |
4043 | register int i; | |
4044 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
4045 | { | |
4046 | if (fmt[i] == 'e') | |
4047 | find_reloads_address_1 (XEXP (x, i), context, &XEXP (x, i), | |
4048 | operand, ind_levels); | |
4049 | } | |
4050 | } | |
4051 | ||
4052 | return 0; | |
4053 | } | |
4054 | \f | |
4055 | /* X, which is found at *LOC, is a part of an address that needs to be | |
4056 | reloaded into a register of class CLASS. If X is a constant, or if | |
4057 | X is a PLUS that contains a constant, check that the constant is a | |
4058 | legitimate operand and that we are supposed to be able to load | |
4059 | it into the register. | |
4060 | ||
4061 | If not, force the constant into memory and reload the MEM instead. | |
4062 | ||
4063 | MODE is the mode to use, in case X is an integer constant. | |
4064 | ||
4065 | NEEDED_FOR says which operand this reload is needed for. | |
4066 | ||
4067 | IND_LEVELS says how many levels of indirect addressing this machine | |
4068 | supports. */ | |
4069 | ||
4070 | static void | |
4071 | find_reloads_address_part (x, loc, class, mode, needed_for, ind_levels) | |
4072 | rtx x; | |
4073 | rtx *loc; | |
4074 | enum reg_class class; | |
4075 | enum machine_mode mode; | |
4076 | rtx needed_for; | |
4077 | int ind_levels; | |
4078 | { | |
4079 | if (CONSTANT_P (x) | |
4080 | && (! LEGITIMATE_CONSTANT_P (x) | |
4081 | || PREFERRED_RELOAD_CLASS (x, class) == NO_REGS)) | |
4082 | { | |
4083 | rtx tem = x = force_const_mem (mode, x); | |
4084 | find_reloads_address (mode, &tem, XEXP (tem, 0), &XEXP (tem, 0), | |
4085 | needed_for, ind_levels); | |
4086 | } | |
4087 | ||
4088 | else if (GET_CODE (x) == PLUS | |
4089 | && CONSTANT_P (XEXP (x, 1)) | |
4090 | && (! LEGITIMATE_CONSTANT_P (XEXP (x, 1)) | |
4091 | || PREFERRED_RELOAD_CLASS (XEXP (x, 1), class) == NO_REGS)) | |
4092 | { | |
4093 | rtx tem = force_const_mem (GET_MODE (x), XEXP (x, 1)); | |
4094 | ||
4095 | x = gen_rtx (PLUS, GET_MODE (x), XEXP (x, 0), tem); | |
4096 | find_reloads_address (mode, &tem, XEXP (tem, 0), &XEXP (tem, 0), | |
4097 | needed_for, ind_levels); | |
4098 | } | |
4099 | ||
4100 | push_reload (x, 0, loc, 0, class, mode, VOIDmode, 0, 0, needed_for); | |
4101 | } | |
4102 | \f | |
4103 | /* Substitute into X the registers into which we have reloaded | |
4104 | the things that need reloading. The array `replacements' | |
4105 | says contains the locations of all pointers that must be changed | |
4106 | and says what to replace them with. | |
4107 | ||
4108 | Return the rtx that X translates into; usually X, but modified. */ | |
4109 | ||
4110 | void | |
4111 | subst_reloads () | |
4112 | { | |
4113 | register int i; | |
4114 | ||
4115 | for (i = 0; i < n_replacements; i++) | |
4116 | { | |
4117 | register struct replacement *r = &replacements[i]; | |
4118 | register rtx reloadreg = reload_reg_rtx[r->what]; | |
4119 | if (reloadreg) | |
4120 | { | |
4121 | /* Encapsulate RELOADREG so its machine mode matches what | |
4122 | used to be there. */ | |
4123 | if (GET_MODE (reloadreg) != r->mode && r->mode != VOIDmode) | |
4124 | reloadreg = gen_rtx (REG, r->mode, REGNO (reloadreg)); | |
4125 | ||
4126 | /* If we are putting this into a SUBREG and RELOADREG is a | |
4127 | SUBREG, we would be making nested SUBREGs, so we have to fix | |
4128 | this up. Note that r->where == &SUBREG_REG (*r->subreg_loc). */ | |
4129 | ||
4130 | if (r->subreg_loc != 0 && GET_CODE (reloadreg) == SUBREG) | |
4131 | { | |
4132 | if (GET_MODE (*r->subreg_loc) | |
4133 | == GET_MODE (SUBREG_REG (reloadreg))) | |
4134 | *r->subreg_loc = SUBREG_REG (reloadreg); | |
4135 | else | |
4136 | { | |
4137 | *r->where = SUBREG_REG (reloadreg); | |
4138 | SUBREG_WORD (*r->subreg_loc) += SUBREG_WORD (reloadreg); | |
4139 | } | |
4140 | } | |
4141 | else | |
4142 | *r->where = reloadreg; | |
4143 | } | |
4144 | /* If reload got no reg and isn't optional, something's wrong. */ | |
4145 | else if (! reload_optional[r->what]) | |
4146 | abort (); | |
4147 | } | |
4148 | } | |
4149 | \f | |
4150 | /* Make a copy of any replacements being done into X and move those copies | |
4151 | to locations in Y, a copy of X. We only look at the highest level of | |
4152 | the RTL. */ | |
4153 | ||
4154 | void | |
4155 | copy_replacements (x, y) | |
4156 | rtx x; | |
4157 | rtx y; | |
4158 | { | |
4159 | int i, j; | |
4160 | enum rtx_code code = GET_CODE (x); | |
4161 | char *fmt = GET_RTX_FORMAT (code); | |
4162 | struct replacement *r; | |
4163 | ||
4164 | /* We can't support X being a SUBREG because we might then need to know its | |
4165 | location if something inside it was replaced. */ | |
4166 | if (code == SUBREG) | |
4167 | abort (); | |
4168 | ||
4169 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
4170 | if (fmt[i] == 'e') | |
4171 | for (j = 0; j < n_replacements; j++) | |
4172 | { | |
4173 | if (replacements[j].subreg_loc == &XEXP (x, i)) | |
4174 | { | |
4175 | r = &replacements[n_replacements++]; | |
4176 | r->where = replacements[j].where; | |
4177 | r->subreg_loc = &XEXP (y, i); | |
4178 | r->what = replacements[j].what; | |
4179 | r->mode = replacements[j].mode; | |
4180 | } | |
4181 | else if (replacements[j].where == &XEXP (x, i)) | |
4182 | { | |
4183 | r = &replacements[n_replacements++]; | |
4184 | r->where = &XEXP (y, i); | |
4185 | r->subreg_loc = 0; | |
4186 | r->what = replacements[j].what; | |
4187 | r->mode = replacements[j].mode; | |
4188 | } | |
4189 | } | |
4190 | } | |
4191 | \f | |
af929c62 RK |
4192 | /* If LOC was scheduled to be replaced by something, return the replacement. |
4193 | Otherwise, return *LOC. */ | |
4194 | ||
4195 | rtx | |
4196 | find_replacement (loc) | |
4197 | rtx *loc; | |
4198 | { | |
4199 | struct replacement *r; | |
4200 | ||
4201 | for (r = &replacements[0]; r < &replacements[n_replacements]; r++) | |
4202 | { | |
4203 | rtx reloadreg = reload_reg_rtx[r->what]; | |
4204 | ||
4205 | if (reloadreg && r->where == loc) | |
4206 | { | |
4207 | if (r->mode != VOIDmode && GET_MODE (reloadreg) != r->mode) | |
4208 | reloadreg = gen_rtx (REG, r->mode, REGNO (reloadreg)); | |
4209 | ||
4210 | return reloadreg; | |
4211 | } | |
4212 | else if (reloadreg && r->subreg_loc == loc) | |
4213 | { | |
4214 | /* RELOADREG must be either a REG or a SUBREG. | |
4215 | ||
4216 | ??? Is it actually still ever a SUBREG? If so, why? */ | |
4217 | ||
4218 | if (GET_CODE (reloadreg) == REG) | |
4219 | return gen_rtx (REG, GET_MODE (*loc), | |
4220 | REGNO (reloadreg) + SUBREG_WORD (*loc)); | |
4221 | else if (GET_MODE (reloadreg) == GET_MODE (*loc)) | |
4222 | return reloadreg; | |
4223 | else | |
4224 | return gen_rtx (SUBREG, GET_MODE (*loc), SUBREG_REG (reloadreg), | |
4225 | SUBREG_WORD (reloadreg) + SUBREG_WORD (*loc)); | |
4226 | } | |
4227 | } | |
4228 | ||
4229 | return *loc; | |
4230 | } | |
4231 | \f | |
eab89b90 RK |
4232 | /* Return nonzero if register in range [REGNO, ENDREGNO) |
4233 | appears either explicitly or implicitly in X | |
4234 | other than being stored into. | |
4235 | ||
4236 | References contained within the substructure at LOC do not count. | |
4237 | LOC may be zero, meaning don't ignore anything. | |
4238 | ||
4239 | This is similar to refers_to_regno_p in rtlanal.c except that we | |
4240 | look at equivalences for pseudos that didn't get hard registers. */ | |
4241 | ||
4242 | int | |
4243 | refers_to_regno_for_reload_p (regno, endregno, x, loc) | |
4244 | int regno, endregno; | |
4245 | rtx x; | |
4246 | rtx *loc; | |
4247 | { | |
4248 | register int i; | |
4249 | register RTX_CODE code; | |
4250 | register char *fmt; | |
4251 | ||
4252 | if (x == 0) | |
4253 | return 0; | |
4254 | ||
4255 | repeat: | |
4256 | code = GET_CODE (x); | |
4257 | ||
4258 | switch (code) | |
4259 | { | |
4260 | case REG: | |
4261 | i = REGNO (x); | |
4262 | ||
4263 | if (i >= FIRST_PSEUDO_REGISTER && reg_renumber[i] == -1 | |
4264 | && ((reg_equiv_address[i] | |
4265 | && refers_to_regno_for_reload_p (regno, endregno, | |
4266 | reg_equiv_address[i], 0)) | |
4267 | || (reg_equiv_mem[i] | |
4268 | && refers_to_regno_for_reload_p (regno, endregno, | |
4269 | XEXP (reg_equiv_mem[i], 0), | |
4270 | 0)))) | |
4271 | return 1; | |
4272 | ||
4273 | return (endregno > i | |
4274 | && regno < i + (i < FIRST_PSEUDO_REGISTER | |
4275 | ? HARD_REGNO_NREGS (i, GET_MODE (x)) | |
4276 | : 1)); | |
4277 | ||
4278 | case SUBREG: | |
4279 | /* If this is a SUBREG of a hard reg, we can see exactly which | |
4280 | registers are being modified. Otherwise, handle normally. */ | |
4281 | if (GET_CODE (SUBREG_REG (x)) == REG | |
4282 | && REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER) | |
4283 | { | |
4284 | int inner_regno = REGNO (SUBREG_REG (x)) + SUBREG_WORD (x); | |
4285 | int inner_endregno | |
4286 | = inner_regno + (inner_regno < FIRST_PSEUDO_REGISTER | |
4287 | ? HARD_REGNO_NREGS (regno, GET_MODE (x)) : 1); | |
4288 | ||
4289 | return endregno > inner_regno && regno < inner_endregno; | |
4290 | } | |
4291 | break; | |
4292 | ||
4293 | case CLOBBER: | |
4294 | case SET: | |
4295 | if (&SET_DEST (x) != loc | |
4296 | /* Note setting a SUBREG counts as referring to the REG it is in for | |
4297 | a pseudo but not for hard registers since we can | |
4298 | treat each word individually. */ | |
4299 | && ((GET_CODE (SET_DEST (x)) == SUBREG | |
4300 | && loc != &SUBREG_REG (SET_DEST (x)) | |
4301 | && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG | |
4302 | && REGNO (SUBREG_REG (SET_DEST (x))) >= FIRST_PSEUDO_REGISTER | |
4303 | && refers_to_regno_for_reload_p (regno, endregno, | |
4304 | SUBREG_REG (SET_DEST (x)), | |
4305 | loc)) | |
4306 | || (GET_CODE (SET_DEST (x)) != REG | |
4307 | && refers_to_regno_for_reload_p (regno, endregno, | |
4308 | SET_DEST (x), loc)))) | |
4309 | return 1; | |
4310 | ||
4311 | if (code == CLOBBER || loc == &SET_SRC (x)) | |
4312 | return 0; | |
4313 | x = SET_SRC (x); | |
4314 | goto repeat; | |
4315 | } | |
4316 | ||
4317 | /* X does not match, so try its subexpressions. */ | |
4318 | ||
4319 | fmt = GET_RTX_FORMAT (code); | |
4320 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
4321 | { | |
4322 | if (fmt[i] == 'e' && loc != &XEXP (x, i)) | |
4323 | { | |
4324 | if (i == 0) | |
4325 | { | |
4326 | x = XEXP (x, 0); | |
4327 | goto repeat; | |
4328 | } | |
4329 | else | |
4330 | if (refers_to_regno_for_reload_p (regno, endregno, | |
4331 | XEXP (x, i), loc)) | |
4332 | return 1; | |
4333 | } | |
4334 | else if (fmt[i] == 'E') | |
4335 | { | |
4336 | register int j; | |
4337 | for (j = XVECLEN (x, i) - 1; j >=0; j--) | |
4338 | if (loc != &XVECEXP (x, i, j) | |
4339 | && refers_to_regno_for_reload_p (regno, endregno, | |
4340 | XVECEXP (x, i, j), loc)) | |
4341 | return 1; | |
4342 | } | |
4343 | } | |
4344 | return 0; | |
4345 | } | |
4346 | \f | |
4347 | #if 0 | |
4348 | ||
4349 | /* [[This function is currently obsolete, now that volatility | |
4350 | is represented by a special bit `volatil' so VOLATILE is never used; | |
4351 | and UNCHANGING has never been brought into use.]] | |
4352 | ||
4353 | Alter X by eliminating all VOLATILE and UNCHANGING expressions. | |
4354 | Each of them is replaced by its operand. | |
4355 | Thus, (PLUS (VOLATILE (MEM (REG 5))) (CONST_INT 4)) | |
4356 | becomes (PLUS (MEM (REG 5)) (CONST_INT 4)). | |
4357 | ||
4358 | If X is itself a VOLATILE expression, | |
4359 | we return the expression that should replace it | |
4360 | but we do not modify X. */ | |
4361 | ||
4362 | static rtx | |
4363 | forget_volatility (x) | |
4364 | register rtx x; | |
4365 | { | |
4366 | enum rtx_code code = GET_CODE (x); | |
4367 | register char *fmt; | |
4368 | register int i; | |
4369 | register rtx value = 0; | |
4370 | ||
4371 | switch (code) | |
4372 | { | |
4373 | case LABEL_REF: | |
4374 | case SYMBOL_REF: | |
4375 | case CONST_INT: | |
4376 | case CONST_DOUBLE: | |
4377 | case CONST: | |
4378 | case REG: | |
4379 | case CC0: | |
4380 | case PC: | |
4381 | return x; | |
4382 | ||
4383 | case VOLATILE: | |
4384 | case UNCHANGING: | |
4385 | return XEXP (x, 0); | |
4386 | } | |
4387 | ||
4388 | fmt = GET_RTX_FORMAT (code); | |
4389 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
4390 | { | |
4391 | if (fmt[i] == 'e') | |
4392 | XEXP (x, i) = forget_volatility (XEXP (x, i)); | |
4393 | if (fmt[i] == 'E') | |
4394 | { | |
4395 | register int j; | |
4396 | for (j = XVECLEN (x, i) - 1; j >= 0; j--) | |
4397 | XVECEXP (x, i, j) = forget_volatility (XVECEXP (x, i, j)); | |
4398 | } | |
4399 | } | |
4400 | ||
4401 | return x; | |
4402 | } | |
4403 | ||
4404 | #endif | |
4405 | \f | |
4406 | /* Check the insns before INSN to see if there is a suitable register | |
4407 | containing the same value as GOAL. | |
4408 | If OTHER is -1, look for a register in class CLASS. | |
4409 | Otherwise, just see if register number OTHER shares GOAL's value. | |
4410 | ||
4411 | Return an rtx for the register found, or zero if none is found. | |
4412 | ||
4413 | If RELOAD_REG_P is (short *)1, | |
4414 | we reject any hard reg that appears in reload_reg_rtx | |
4415 | because such a hard reg is also needed coming into this insn. | |
4416 | ||
4417 | If RELOAD_REG_P is any other nonzero value, | |
4418 | it is a vector indexed by hard reg number | |
4419 | and we reject any hard reg whose element in the vector is nonnegative | |
4420 | as well as any that appears in reload_reg_rtx. | |
4421 | ||
4422 | If GOAL is zero, then GOALREG is a register number; we look | |
4423 | for an equivalent for that register. | |
4424 | ||
4425 | MODE is the machine mode of the value we want an equivalence for. | |
4426 | If GOAL is nonzero and not VOIDmode, then it must have mode MODE. | |
4427 | ||
4428 | This function is used by jump.c as well as in the reload pass. | |
4429 | ||
4430 | If GOAL is the sum of the stack pointer and a constant, we treat it | |
4431 | as if it were a constant except that sp is required to be unchanging. */ | |
4432 | ||
4433 | rtx | |
4434 | find_equiv_reg (goal, insn, class, other, reload_reg_p, goalreg, mode) | |
4435 | register rtx goal; | |
4436 | rtx insn; | |
4437 | enum reg_class class; | |
4438 | register int other; | |
4439 | short *reload_reg_p; | |
4440 | int goalreg; | |
4441 | enum machine_mode mode; | |
4442 | { | |
4443 | register rtx p = insn; | |
4444 | rtx valtry, value, where; | |
4445 | register rtx pat; | |
4446 | register int regno = -1; | |
4447 | int valueno; | |
4448 | int goal_mem = 0; | |
4449 | int goal_const = 0; | |
4450 | int goal_mem_addr_varies = 0; | |
4451 | int need_stable_sp = 0; | |
4452 | int nregs; | |
4453 | int valuenregs; | |
4454 | ||
4455 | if (goal == 0) | |
4456 | regno = goalreg; | |
4457 | else if (GET_CODE (goal) == REG) | |
4458 | regno = REGNO (goal); | |
4459 | else if (GET_CODE (goal) == MEM) | |
4460 | { | |
4461 | enum rtx_code code = GET_CODE (XEXP (goal, 0)); | |
4462 | if (MEM_VOLATILE_P (goal)) | |
4463 | return 0; | |
4464 | if (flag_float_store && GET_MODE_CLASS (GET_MODE (goal)) == MODE_FLOAT) | |
4465 | return 0; | |
4466 | /* An address with side effects must be reexecuted. */ | |
4467 | switch (code) | |
4468 | { | |
4469 | case POST_INC: | |
4470 | case PRE_INC: | |
4471 | case POST_DEC: | |
4472 | case PRE_DEC: | |
4473 | return 0; | |
4474 | } | |
4475 | goal_mem = 1; | |
4476 | } | |
4477 | else if (CONSTANT_P (goal)) | |
4478 | goal_const = 1; | |
4479 | else if (GET_CODE (goal) == PLUS | |
4480 | && XEXP (goal, 0) == stack_pointer_rtx | |
4481 | && CONSTANT_P (XEXP (goal, 1))) | |
4482 | goal_const = need_stable_sp = 1; | |
4483 | else | |
4484 | return 0; | |
4485 | ||
4486 | /* On some machines, certain regs must always be rejected | |
4487 | because they don't behave the way ordinary registers do. */ | |
4488 | ||
4489 | #ifdef OVERLAPPING_REGNO_P | |
4490 | if (regno >= 0 && regno < FIRST_PSEUDO_REGISTER | |
4491 | && OVERLAPPING_REGNO_P (regno)) | |
4492 | return 0; | |
4493 | #endif | |
4494 | ||
4495 | /* Scan insns back from INSN, looking for one that copies | |
4496 | a value into or out of GOAL. | |
4497 | Stop and give up if we reach a label. */ | |
4498 | ||
4499 | while (1) | |
4500 | { | |
4501 | p = PREV_INSN (p); | |
4502 | if (p == 0 || GET_CODE (p) == CODE_LABEL) | |
4503 | return 0; | |
4504 | if (GET_CODE (p) == INSN | |
4505 | /* If we don't want spill regs ... */ | |
4506 | && (! (reload_reg_p != 0 && reload_reg_p != (short *)1) | |
4507 | /* ... then ignore insns introduced by reload; they aren't useful | |
4508 | and can cause results in reload_as_needed to be different | |
4509 | from what they were when calculating the need for spills. | |
4510 | If we notice an input-reload insn here, we will reject it below, | |
4511 | but it might hide a usable equivalent. That makes bad code. | |
4512 | It may even abort: perhaps no reg was spilled for this insn | |
4513 | because it was assumed we would find that equivalent. */ | |
4514 | || INSN_UID (p) < reload_first_uid)) | |
4515 | { | |
e8094962 | 4516 | rtx tem; |
eab89b90 RK |
4517 | pat = single_set (p); |
4518 | /* First check for something that sets some reg equal to GOAL. */ | |
4519 | if (pat != 0 | |
4520 | && ((regno >= 0 | |
4521 | && true_regnum (SET_SRC (pat)) == regno | |
4522 | && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0) | |
4523 | || | |
4524 | (regno >= 0 | |
4525 | && true_regnum (SET_DEST (pat)) == regno | |
4526 | && (valueno = true_regnum (valtry = SET_SRC (pat))) >= 0) | |
4527 | || | |
4528 | (goal_const && rtx_equal_p (SET_SRC (pat), goal) | |
4529 | && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0) | |
4530 | || (goal_mem | |
4531 | && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0 | |
4532 | && rtx_renumbered_equal_p (goal, SET_SRC (pat))) | |
4533 | || (goal_mem | |
4534 | && (valueno = true_regnum (valtry = SET_SRC (pat))) >= 0 | |
e8094962 RK |
4535 | && rtx_renumbered_equal_p (goal, SET_DEST (pat))) |
4536 | /* If we are looking for a constant, | |
4537 | and something equivalent to that constant was copied | |
4538 | into a reg, we can use that reg. */ | |
4539 | || (goal_const && (tem = find_reg_note (p, REG_EQUIV, 0)) | |
4540 | && rtx_equal_p (XEXP (tem, 0), goal) | |
4541 | && (valueno = true_regnum (valtry = SET_DEST (pat)))) | |
4542 | || (goal_const && (tem = find_reg_note (p, REG_EQUIV, 0)) | |
4543 | && GET_CODE (SET_DEST (pat)) == REG | |
4544 | && GET_CODE (XEXP (tem, 0)) == CONST_DOUBLE | |
4545 | && GET_MODE_CLASS (GET_MODE (XEXP (tem, 0))) == MODE_FLOAT | |
4546 | && GET_CODE (goal) == CONST_INT | |
4547 | && INTVAL (goal) == CONST_DOUBLE_LOW (XEXP (tem, 0)) | |
4548 | && (valtry = operand_subword (SET_DEST (pat), 0, 0, | |
4549 | VOIDmode)) | |
4550 | && (valueno = true_regnum (valtry))) | |
4551 | || (goal_const && (tem = find_reg_note (p, REG_EQUIV, 0)) | |
4552 | && GET_CODE (SET_DEST (pat)) == REG | |
4553 | && GET_CODE (XEXP (tem, 0)) == CONST_DOUBLE | |
4554 | && GET_MODE_CLASS (GET_MODE (XEXP (tem, 0))) == MODE_FLOAT | |
4555 | && GET_CODE (goal) == CONST_INT | |
4556 | && INTVAL (goal) == CONST_DOUBLE_HIGH (XEXP (tem, 0)) | |
4557 | && (valtry | |
4558 | = operand_subword (SET_DEST (pat), 1, 0, VOIDmode)) | |
4559 | && (valueno = true_regnum (valtry))))) | |
eab89b90 RK |
4560 | if (other >= 0 |
4561 | ? valueno == other | |
4562 | : ((unsigned) valueno < FIRST_PSEUDO_REGISTER | |
4563 | && TEST_HARD_REG_BIT (reg_class_contents[(int) class], | |
4564 | valueno))) | |
4565 | { | |
4566 | value = valtry; | |
4567 | where = p; | |
4568 | break; | |
4569 | } | |
4570 | } | |
4571 | } | |
4572 | ||
4573 | /* We found a previous insn copying GOAL into a suitable other reg VALUE | |
4574 | (or copying VALUE into GOAL, if GOAL is also a register). | |
4575 | Now verify that VALUE is really valid. */ | |
4576 | ||
4577 | /* VALUENO is the register number of VALUE; a hard register. */ | |
4578 | ||
4579 | /* Don't try to re-use something that is killed in this insn. We want | |
4580 | to be able to trust REG_UNUSED notes. */ | |
4581 | if (find_reg_note (where, REG_UNUSED, value)) | |
4582 | return 0; | |
4583 | ||
4584 | /* If we propose to get the value from the stack pointer or if GOAL is | |
4585 | a MEM based on the stack pointer, we need a stable SP. */ | |
4586 | if (valueno == STACK_POINTER_REGNUM | |
4587 | || (goal_mem && reg_overlap_mentioned_p (stack_pointer_rtx, goal))) | |
4588 | need_stable_sp = 1; | |
4589 | ||
4590 | /* Reject VALUE if the copy-insn moved the wrong sort of datum. */ | |
4591 | if (GET_MODE (value) != mode) | |
4592 | return 0; | |
4593 | ||
4594 | /* Reject VALUE if it was loaded from GOAL | |
4595 | and is also a register that appears in the address of GOAL. */ | |
4596 | ||
4597 | if (goal_mem && value == SET_DEST (PATTERN (where)) | |
4598 | && refers_to_regno_p (valueno, | |
4599 | valueno + HARD_REGNO_NREGS (valueno, mode), | |
4600 | goal, 0)) | |
4601 | return 0; | |
4602 | ||
4603 | /* Reject registers that overlap GOAL. */ | |
4604 | ||
4605 | if (!goal_mem && !goal_const | |
4606 | && regno + HARD_REGNO_NREGS (regno, mode) > valueno | |
4607 | && regno < valueno + HARD_REGNO_NREGS (valueno, mode)) | |
4608 | return 0; | |
4609 | ||
4610 | /* Reject VALUE if it is one of the regs reserved for reloads. | |
4611 | Reload1 knows how to reuse them anyway, and it would get | |
4612 | confused if we allocated one without its knowledge. | |
4613 | (Now that insns introduced by reload are ignored above, | |
4614 | this case shouldn't happen, but I'm not positive.) */ | |
4615 | ||
4616 | if (reload_reg_p != 0 && reload_reg_p != (short *)1 | |
4617 | && reload_reg_p[valueno] >= 0) | |
4618 | return 0; | |
4619 | ||
4620 | /* On some machines, certain regs must always be rejected | |
4621 | because they don't behave the way ordinary registers do. */ | |
4622 | ||
4623 | #ifdef OVERLAPPING_REGNO_P | |
4624 | if (OVERLAPPING_REGNO_P (valueno)) | |
4625 | return 0; | |
4626 | #endif | |
4627 | ||
4628 | nregs = HARD_REGNO_NREGS (regno, mode); | |
4629 | valuenregs = HARD_REGNO_NREGS (valueno, mode); | |
4630 | ||
4631 | /* Reject VALUE if it is a register being used for an input reload | |
4632 | even if it is not one of those reserved. */ | |
4633 | ||
4634 | if (reload_reg_p != 0) | |
4635 | { | |
4636 | int i; | |
4637 | for (i = 0; i < n_reloads; i++) | |
4638 | if (reload_reg_rtx[i] != 0 && reload_in[i]) | |
4639 | { | |
4640 | int regno1 = REGNO (reload_reg_rtx[i]); | |
4641 | int nregs1 = HARD_REGNO_NREGS (regno1, | |
4642 | GET_MODE (reload_reg_rtx[i])); | |
4643 | if (regno1 < valueno + valuenregs | |
4644 | && regno1 + nregs1 > valueno) | |
4645 | return 0; | |
4646 | } | |
4647 | } | |
4648 | ||
4649 | if (goal_mem) | |
4650 | goal_mem_addr_varies = rtx_addr_varies_p (goal); | |
4651 | ||
4652 | /* Now verify that the values of GOAL and VALUE remain unaltered | |
4653 | until INSN is reached. */ | |
4654 | ||
4655 | p = insn; | |
4656 | while (1) | |
4657 | { | |
4658 | p = PREV_INSN (p); | |
4659 | if (p == where) | |
4660 | return value; | |
4661 | ||
4662 | /* Don't trust the conversion past a function call | |
4663 | if either of the two is in a call-clobbered register, or memory. */ | |
4664 | if (GET_CODE (p) == CALL_INSN | |
4665 | && ((regno >= 0 && regno < FIRST_PSEUDO_REGISTER | |
4666 | && call_used_regs[regno]) | |
4667 | || | |
4668 | (valueno >= 0 && valueno < FIRST_PSEUDO_REGISTER | |
4669 | && call_used_regs[valueno]) | |
4670 | || | |
4671 | goal_mem | |
4672 | || need_stable_sp)) | |
4673 | return 0; | |
4674 | ||
4675 | #ifdef INSN_CLOBBERS_REGNO_P | |
4676 | if ((valueno >= 0 && valueno < FIRST_PSEUDO_REGISTER | |
4677 | && INSN_CLOBBERS_REGNO_P (p, valueno)) | |
4678 | || (regno >= 0 && regno < FIRST_PSEUDO_REGISTER | |
4679 | && INSN_CLOBBERS_REGNO_P (p, regno))) | |
4680 | return 0; | |
4681 | #endif | |
4682 | ||
4683 | if (GET_RTX_CLASS (GET_CODE (p)) == 'i') | |
4684 | { | |
4685 | /* If this insn P stores in either GOAL or VALUE, return 0. | |
4686 | If GOAL is a memory ref and this insn writes memory, return 0. | |
4687 | If GOAL is a memory ref and its address is not constant, | |
4688 | and this insn P changes a register used in GOAL, return 0. */ | |
4689 | ||
4690 | pat = PATTERN (p); | |
4691 | if (GET_CODE (pat) == SET || GET_CODE (pat) == CLOBBER) | |
4692 | { | |
4693 | register rtx dest = SET_DEST (pat); | |
4694 | while (GET_CODE (dest) == SUBREG | |
4695 | || GET_CODE (dest) == ZERO_EXTRACT | |
4696 | || GET_CODE (dest) == SIGN_EXTRACT | |
4697 | || GET_CODE (dest) == STRICT_LOW_PART) | |
4698 | dest = XEXP (dest, 0); | |
4699 | if (GET_CODE (dest) == REG) | |
4700 | { | |
4701 | register int xregno = REGNO (dest); | |
4702 | int xnregs; | |
4703 | if (REGNO (dest) < FIRST_PSEUDO_REGISTER) | |
4704 | xnregs = HARD_REGNO_NREGS (xregno, GET_MODE (dest)); | |
4705 | else | |
4706 | xnregs = 1; | |
4707 | if (xregno < regno + nregs && xregno + xnregs > regno) | |
4708 | return 0; | |
4709 | if (xregno < valueno + valuenregs | |
4710 | && xregno + xnregs > valueno) | |
4711 | return 0; | |
4712 | if (goal_mem_addr_varies | |
4713 | && reg_overlap_mentioned_p (dest, goal)) | |
4714 | return 0; | |
4715 | } | |
4716 | else if (goal_mem && GET_CODE (dest) == MEM | |
4717 | && ! push_operand (dest, GET_MODE (dest))) | |
4718 | return 0; | |
4719 | else if (need_stable_sp && push_operand (dest, GET_MODE (dest))) | |
4720 | return 0; | |
4721 | } | |
4722 | else if (GET_CODE (pat) == PARALLEL) | |
4723 | { | |
4724 | register int i; | |
4725 | for (i = XVECLEN (pat, 0) - 1; i >= 0; i--) | |
4726 | { | |
4727 | register rtx v1 = XVECEXP (pat, 0, i); | |
4728 | if (GET_CODE (v1) == SET || GET_CODE (v1) == CLOBBER) | |
4729 | { | |
4730 | register rtx dest = SET_DEST (v1); | |
4731 | while (GET_CODE (dest) == SUBREG | |
4732 | || GET_CODE (dest) == ZERO_EXTRACT | |
4733 | || GET_CODE (dest) == SIGN_EXTRACT | |
4734 | || GET_CODE (dest) == STRICT_LOW_PART) | |
4735 | dest = XEXP (dest, 0); | |
4736 | if (GET_CODE (dest) == REG) | |
4737 | { | |
4738 | register int xregno = REGNO (dest); | |
4739 | int xnregs; | |
4740 | if (REGNO (dest) < FIRST_PSEUDO_REGISTER) | |
4741 | xnregs = HARD_REGNO_NREGS (xregno, GET_MODE (dest)); | |
4742 | else | |
4743 | xnregs = 1; | |
4744 | if (xregno < regno + nregs | |
4745 | && xregno + xnregs > regno) | |
4746 | return 0; | |
4747 | if (xregno < valueno + valuenregs | |
4748 | && xregno + xnregs > valueno) | |
4749 | return 0; | |
4750 | if (goal_mem_addr_varies | |
4751 | && reg_overlap_mentioned_p (dest, goal)) | |
4752 | return 0; | |
4753 | } | |
4754 | else if (goal_mem && GET_CODE (dest) == MEM | |
4755 | && ! push_operand (dest, GET_MODE (dest))) | |
4756 | return 0; | |
4757 | else if (need_stable_sp | |
4758 | && push_operand (dest, GET_MODE (dest))) | |
4759 | return 0; | |
4760 | } | |
4761 | } | |
4762 | } | |
4763 | ||
4764 | #ifdef AUTO_INC_DEC | |
4765 | /* If this insn auto-increments or auto-decrements | |
4766 | either regno or valueno, return 0 now. | |
4767 | If GOAL is a memory ref and its address is not constant, | |
4768 | and this insn P increments a register used in GOAL, return 0. */ | |
4769 | { | |
4770 | register rtx link; | |
4771 | ||
4772 | for (link = REG_NOTES (p); link; link = XEXP (link, 1)) | |
4773 | if (REG_NOTE_KIND (link) == REG_INC | |
4774 | && GET_CODE (XEXP (link, 0)) == REG) | |
4775 | { | |
4776 | register int incno = REGNO (XEXP (link, 0)); | |
4777 | if (incno < regno + nregs && incno >= regno) | |
4778 | return 0; | |
4779 | if (incno < valueno + valuenregs && incno >= valueno) | |
4780 | return 0; | |
4781 | if (goal_mem_addr_varies | |
4782 | && reg_overlap_mentioned_p (XEXP (link, 0), goal)) | |
4783 | return 0; | |
4784 | } | |
4785 | } | |
4786 | #endif | |
4787 | } | |
4788 | } | |
4789 | } | |
4790 | \f | |
4791 | /* Find a place where INCED appears in an increment or decrement operator | |
4792 | within X, and return the amount INCED is incremented or decremented by. | |
4793 | The value is always positive. */ | |
4794 | ||
4795 | static int | |
4796 | find_inc_amount (x, inced) | |
4797 | rtx x, inced; | |
4798 | { | |
4799 | register enum rtx_code code = GET_CODE (x); | |
4800 | register char *fmt; | |
4801 | register int i; | |
4802 | ||
4803 | if (code == MEM) | |
4804 | { | |
4805 | register rtx addr = XEXP (x, 0); | |
4806 | if ((GET_CODE (addr) == PRE_DEC | |
4807 | || GET_CODE (addr) == POST_DEC | |
4808 | || GET_CODE (addr) == PRE_INC | |
4809 | || GET_CODE (addr) == POST_INC) | |
4810 | && XEXP (addr, 0) == inced) | |
4811 | return GET_MODE_SIZE (GET_MODE (x)); | |
4812 | } | |
4813 | ||
4814 | fmt = GET_RTX_FORMAT (code); | |
4815 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
4816 | { | |
4817 | if (fmt[i] == 'e') | |
4818 | { | |
4819 | register int tem = find_inc_amount (XEXP (x, i), inced); | |
4820 | if (tem != 0) | |
4821 | return tem; | |
4822 | } | |
4823 | if (fmt[i] == 'E') | |
4824 | { | |
4825 | register int j; | |
4826 | for (j = XVECLEN (x, i) - 1; j >= 0; j--) | |
4827 | { | |
4828 | register int tem = find_inc_amount (XVECEXP (x, i, j), inced); | |
4829 | if (tem != 0) | |
4830 | return tem; | |
4831 | } | |
4832 | } | |
4833 | } | |
4834 | ||
4835 | return 0; | |
4836 | } | |
4837 | \f | |
4838 | /* Return 1 if register REGNO is the subject of a clobber in insn INSN. */ | |
4839 | ||
4840 | int | |
4841 | regno_clobbered_p (regno, insn) | |
4842 | int regno; | |
4843 | rtx insn; | |
4844 | { | |
4845 | if (GET_CODE (PATTERN (insn)) == CLOBBER | |
4846 | && GET_CODE (XEXP (PATTERN (insn), 0)) == REG) | |
4847 | return REGNO (XEXP (PATTERN (insn), 0)) == regno; | |
4848 | ||
4849 | if (GET_CODE (PATTERN (insn)) == PARALLEL) | |
4850 | { | |
4851 | int i = XVECLEN (PATTERN (insn), 0) - 1; | |
4852 | ||
4853 | for (; i >= 0; i--) | |
4854 | { | |
4855 | rtx elt = XVECEXP (PATTERN (insn), 0, i); | |
4856 | if (GET_CODE (elt) == CLOBBER && GET_CODE (XEXP (elt, 0)) == REG | |
4857 | && REGNO (XEXP (elt, 0)) == regno) | |
4858 | return 1; | |
4859 | } | |
4860 | } | |
4861 | ||
4862 | return 0; | |
4863 | } |