1 /* Code for RTL transformations to satisfy insn constraints.
2    Copyright (C) 2010-2021 Free Software Foundation, Inc.
3    Contributed by Vladimir Makarov <vmakarov@redhat.com>.
4 
5    This file is part of GCC.
6 
7    GCC is free software; you can redistribute it and/or modify it under
8    the terms of the GNU General Public License as published by the Free
9    Software Foundation; either version 3, or (at your option) any later
10    version.
11 
12    GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13    WARRANTY; without even the implied warranty of MERCHANTABILITY or
14    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15    for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with GCC; see the file COPYING3.  If not see
19    <http://www.gnu.org/licenses/>.  */
20 
21 
22 /* This file contains code for 3 passes: constraint pass,
23    inheritance/split pass, and pass for undoing failed inheritance and
24    split.
25 
26    The major goal of constraint pass is to transform RTL to satisfy
27    insn and address constraints by:
28      o choosing insn alternatives;
29      o generating *reload insns* (or reloads in brief) and *reload
30        pseudos* which will get necessary hard registers later;
31      o substituting pseudos with equivalent values and removing the
32        instructions that initialized those pseudos.
33 
34    The constraint pass has biggest and most complicated code in LRA.
35    There are a lot of important details like:
36      o reuse of input reload pseudos to simplify reload pseudo
37        allocations;
38      o some heuristics to choose insn alternative to improve the
39        inheritance;
40      o early clobbers etc.
41 
42    The pass is mimicking former reload pass in alternative choosing
43    because the reload pass is oriented to current machine description
44    model.  It might be changed if the machine description model is
45    changed.
46 
47    There is special code for preventing all LRA and this pass cycling
48    in case of bugs.
49 
50    On the first iteration of the pass we process every instruction and
51    choose an alternative for each one.  On subsequent iterations we try
52    to avoid reprocessing instructions if we can be sure that the old
53    choice is still valid.
54 
55    The inheritance/spilt pass is to transform code to achieve
56    ineheritance and live range splitting.  It is done on backward
57    traversal of EBBs.
58 
59    The inheritance optimization goal is to reuse values in hard
60    registers. There is analogous optimization in old reload pass.  The
61    inheritance is achieved by following transformation:
62 
63        reload_p1 <- p	     reload_p1 <- p
64        ...		     new_p <- reload_p1
65        ...		=>   ...
66        reload_p2 <- p	     reload_p2 <- new_p
67 
68    where p is spilled and not changed between the insns.  Reload_p1 is
69    also called *original pseudo* and new_p is called *inheritance
70    pseudo*.
71 
72    The subsequent assignment pass will try to assign the same (or
73    another if it is not possible) hard register to new_p as to
74    reload_p1 or reload_p2.
75 
76    If the assignment pass fails to assign a hard register to new_p,
77    this file will undo the inheritance and restore the original code.
78    This is because implementing the above sequence with a spilled
79    new_p would make the code much worse.  The inheritance is done in
80    EBB scope.  The above is just a simplified example to get an idea
81    of the inheritance as the inheritance is also done for non-reload
82    insns.
83 
84    Splitting (transformation) is also done in EBB scope on the same
85    pass as the inheritance:
86 
87        r <- ... or ... <- r		 r <- ... or ... <- r
88        ...				 s <- r (new insn -- save)
89        ...			  =>
90        ...				 r <- s (new insn -- restore)
91        ... <- r				 ... <- r
92 
93     The *split pseudo* s is assigned to the hard register of the
94     original pseudo or hard register r.
95 
96     Splitting is done:
97       o In EBBs with high register pressure for global pseudos (living
98 	in at least 2 BBs) and assigned to hard registers when there
99 	are more one reloads needing the hard registers;
100       o for pseudos needing save/restore code around calls.
101 
102     If the split pseudo still has the same hard register as the
103     original pseudo after the subsequent assignment pass or the
104     original pseudo was split, the opposite transformation is done on
105     the same pass for undoing inheritance.  */
106 
107 #undef REG_OK_STRICT
108 
109 #include "config.h"
110 #include "system.h"
111 #include "coretypes.h"
112 #include "backend.h"
113 #include "target.h"
114 #include "rtl.h"
115 #include "tree.h"
116 #include "predict.h"
117 #include "df.h"
118 #include "memmodel.h"
119 #include "tm_p.h"
120 #include "expmed.h"
121 #include "optabs.h"
122 #include "regs.h"
123 #include "ira.h"
124 #include "recog.h"
125 #include "output.h"
126 #include "addresses.h"
127 #include "expr.h"
128 #include "cfgrtl.h"
129 #include "rtl-error.h"
130 #include "lra.h"
131 #include "lra-int.h"
132 #include "print-rtl.h"
133 #include "function-abi.h"
134 #include "rtl-iter.h"
135 
136 /* Value of LRA_CURR_RELOAD_NUM at the beginning of BB of the current
137    insn.  Remember that LRA_CURR_RELOAD_NUM is the number of emitted
138    reload insns.  */
139 static int bb_reload_num;
140 
141 /* The current insn being processed and corresponding its single set
142    (NULL otherwise), its data (basic block, the insn data, the insn
143    static data, and the mode of each operand).  */
144 static rtx_insn *curr_insn;
145 static rtx curr_insn_set;
146 static basic_block curr_bb;
147 static lra_insn_recog_data_t curr_id;
148 static struct lra_static_insn_data *curr_static_id;
149 static machine_mode curr_operand_mode[MAX_RECOG_OPERANDS];
150 /* Mode of the register substituted by its equivalence with VOIDmode
151    (e.g. constant) and whose subreg is given operand of the current
152    insn.  VOIDmode in all other cases.  */
153 static machine_mode original_subreg_reg_mode[MAX_RECOG_OPERANDS];
154 
155 
156 
157 /* Start numbers for new registers and insns at the current constraints
158    pass start.	*/
159 static int new_regno_start;
160 static int new_insn_uid_start;
161 
162 /* If LOC is nonnull, strip any outer subreg from it.  */
163 static inline rtx *
strip_subreg(rtx * loc)164 strip_subreg (rtx *loc)
165 {
166   return loc && GET_CODE (*loc) == SUBREG ? &SUBREG_REG (*loc) : loc;
167 }
168 
169 /* Return hard regno of REGNO or if it is was not assigned to a hard
170    register, use a hard register from its allocno class.  */
171 static int
get_try_hard_regno(int regno)172 get_try_hard_regno (int regno)
173 {
174   int hard_regno;
175   enum reg_class rclass;
176 
177   if ((hard_regno = regno) >= FIRST_PSEUDO_REGISTER)
178     hard_regno = lra_get_regno_hard_regno (regno);
179   if (hard_regno >= 0)
180     return hard_regno;
181   rclass = lra_get_allocno_class (regno);
182   if (rclass == NO_REGS)
183     return -1;
184   return ira_class_hard_regs[rclass][0];
185 }
186 
187 /* Return the hard regno of X after removing its subreg.  If X is not
188    a register or a subreg of a register, return -1.  If X is a pseudo,
189    use its assignment.  If FINAL_P return the final hard regno which will
190    be after elimination.  */
191 static int
get_hard_regno(rtx x,bool final_p)192 get_hard_regno (rtx x, bool final_p)
193 {
194   rtx reg;
195   int hard_regno;
196 
197   reg = x;
198   if (SUBREG_P (x))
199     reg = SUBREG_REG (x);
200   if (! REG_P (reg))
201     return -1;
202   if (! HARD_REGISTER_NUM_P (hard_regno = REGNO (reg)))
203     hard_regno = lra_get_regno_hard_regno (hard_regno);
204   if (hard_regno < 0)
205     return -1;
206   if (final_p)
207     hard_regno = lra_get_elimination_hard_regno (hard_regno);
208   if (SUBREG_P (x))
209     hard_regno += subreg_regno_offset (hard_regno, GET_MODE (reg),
210 				       SUBREG_BYTE (x),  GET_MODE (x));
211   return hard_regno;
212 }
213 
214 /* If REGNO is a hard register or has been allocated a hard register,
215    return the class of that register.  If REGNO is a reload pseudo
216    created by the current constraints pass, return its allocno class.
217    Return NO_REGS otherwise.  */
218 static enum reg_class
get_reg_class(int regno)219 get_reg_class (int regno)
220 {
221   int hard_regno;
222 
223   if (! HARD_REGISTER_NUM_P (hard_regno = regno))
224     hard_regno = lra_get_regno_hard_regno (regno);
225   if (hard_regno >= 0)
226     {
227       hard_regno = lra_get_elimination_hard_regno (hard_regno);
228       return REGNO_REG_CLASS (hard_regno);
229     }
230   if (regno >= new_regno_start)
231     return lra_get_allocno_class (regno);
232   return NO_REGS;
233 }
234 
235 /* Return true if REG satisfies (or will satisfy) reg class constraint
236    CL.  Use elimination first if REG is a hard register.  If REG is a
237    reload pseudo created by this constraints pass, assume that it will
238    be allocated a hard register from its allocno class, but allow that
239    class to be narrowed to CL if it is currently a superset of CL and
240    if either:
241 
242    - ALLOW_ALL_RELOAD_CLASS_CHANGES_P is true or
243    - the instruction we're processing is not a reload move.
244 
245    If NEW_CLASS is nonnull, set *NEW_CLASS to the new allocno class of
246    REGNO (reg), or NO_REGS if no change in its class was needed.  */
247 static bool
248 in_class_p (rtx reg, enum reg_class cl, enum reg_class *new_class,
249 	    bool allow_all_reload_class_changes_p = false)
250 {
251   enum reg_class rclass, common_class;
252   machine_mode reg_mode;
253   rtx src;
254   int class_size, hard_regno, nregs, i, j;
255   int regno = REGNO (reg);
256 
257   if (new_class != NULL)
258     *new_class = NO_REGS;
259   if (regno < FIRST_PSEUDO_REGISTER)
260     {
261       rtx final_reg = reg;
262       rtx *final_loc = &final_reg;
263 
264       lra_eliminate_reg_if_possible (final_loc);
265       return TEST_HARD_REG_BIT (reg_class_contents[cl], REGNO (*final_loc));
266     }
267   reg_mode = GET_MODE (reg);
268   rclass = get_reg_class (regno);
269   src = curr_insn_set != NULL ? SET_SRC (curr_insn_set) : NULL;
270   if (regno < new_regno_start
271       /* Do not allow the constraints for reload instructions to
272 	 influence the classes of new pseudos.  These reloads are
273 	 typically moves that have many alternatives, and restricting
274 	 reload pseudos for one alternative may lead to situations
275 	 where other reload pseudos are no longer allocatable.  */
276       || (!allow_all_reload_class_changes_p
277 	  && INSN_UID (curr_insn) >= new_insn_uid_start
278 	  && src != NULL
279 	  && ((REG_P (src) || MEM_P (src))
280 	      || (GET_CODE (src) == SUBREG
281 		  && (REG_P (SUBREG_REG (src)) || MEM_P (SUBREG_REG (src)))))))
282     /* When we don't know what class will be used finally for reload
283        pseudos, we use ALL_REGS.  */
284     return ((regno >= new_regno_start && rclass == ALL_REGS)
285 	    || (rclass != NO_REGS && ira_class_subset_p[rclass][cl]
286 		&& ! hard_reg_set_subset_p (reg_class_contents[cl],
287 					    lra_no_alloc_regs)));
288   else
289     {
290       common_class = ira_reg_class_subset[rclass][cl];
291       if (new_class != NULL)
292 	*new_class = common_class;
293       if (hard_reg_set_subset_p (reg_class_contents[common_class],
294 				 lra_no_alloc_regs))
295 	return false;
296       /* Check that there are enough allocatable regs.  */
297       class_size = ira_class_hard_regs_num[common_class];
298       for (i = 0; i < class_size; i++)
299 	{
300 	  hard_regno = ira_class_hard_regs[common_class][i];
301 	  nregs = hard_regno_nregs (hard_regno, reg_mode);
302 	  if (nregs == 1)
303 	    return true;
304 	  for (j = 0; j < nregs; j++)
305 	    if (TEST_HARD_REG_BIT (lra_no_alloc_regs, hard_regno + j)
306 		|| ! TEST_HARD_REG_BIT (reg_class_contents[common_class],
307 					hard_regno + j))
308 	      break;
309 	  if (j >= nregs)
310 	    return true;
311 	}
312       return false;
313     }
314 }
315 
316 /* Return true if REGNO satisfies a memory constraint.	*/
317 static bool
in_mem_p(int regno)318 in_mem_p (int regno)
319 {
320   return get_reg_class (regno) == NO_REGS;
321 }
322 
323 /* Return 1 if ADDR is a valid memory address for mode MODE in address
324    space AS, and check that each pseudo has the proper kind of hard
325    reg.	 */
326 static int
valid_address_p(machine_mode mode ATTRIBUTE_UNUSED,rtx addr,addr_space_t as)327 valid_address_p (machine_mode mode ATTRIBUTE_UNUSED,
328 		 rtx addr, addr_space_t as)
329 {
330 #ifdef GO_IF_LEGITIMATE_ADDRESS
331   lra_assert (ADDR_SPACE_GENERIC_P (as));
332   GO_IF_LEGITIMATE_ADDRESS (mode, addr, win);
333   return 0;
334 
335  win:
336   return 1;
337 #else
338   return targetm.addr_space.legitimate_address_p (mode, addr, 0, as);
339 #endif
340 }
341 
342 namespace {
343   /* Temporarily eliminates registers in an address (for the lifetime of
344      the object).  */
345   class address_eliminator {
346   public:
347     address_eliminator (struct address_info *ad);
348     ~address_eliminator ();
349 
350   private:
351     struct address_info *m_ad;
352     rtx *m_base_loc;
353     rtx m_base_reg;
354     rtx *m_index_loc;
355     rtx m_index_reg;
356   };
357 }
358 
address_eliminator(struct address_info * ad)359 address_eliminator::address_eliminator (struct address_info *ad)
360   : m_ad (ad),
361     m_base_loc (strip_subreg (ad->base_term)),
362     m_base_reg (NULL_RTX),
363     m_index_loc (strip_subreg (ad->index_term)),
364     m_index_reg (NULL_RTX)
365 {
366   if (m_base_loc != NULL)
367     {
368       m_base_reg = *m_base_loc;
369       /* If we have non-legitimate address which is decomposed not in
370 	 the way we expected, don't do elimination here.  In such case
371 	 the address will be reloaded and elimination will be done in
372 	 reload insn finally.  */
373       if (REG_P (m_base_reg))
374 	lra_eliminate_reg_if_possible (m_base_loc);
375       if (m_ad->base_term2 != NULL)
376 	*m_ad->base_term2 = *m_ad->base_term;
377     }
378   if (m_index_loc != NULL)
379     {
380       m_index_reg = *m_index_loc;
381       if (REG_P (m_index_reg))
382 	lra_eliminate_reg_if_possible (m_index_loc);
383     }
384 }
385 
~address_eliminator()386 address_eliminator::~address_eliminator ()
387 {
388   if (m_base_loc && *m_base_loc != m_base_reg)
389     {
390       *m_base_loc = m_base_reg;
391       if (m_ad->base_term2 != NULL)
392 	*m_ad->base_term2 = *m_ad->base_term;
393     }
394   if (m_index_loc && *m_index_loc != m_index_reg)
395     *m_index_loc = m_index_reg;
396 }
397 
398 /* Return true if the eliminated form of AD is a legitimate target address.
399    If OP is a MEM, AD is the address within OP, otherwise OP should be
400    ignored.  CONSTRAINT is one constraint that the operand may need
401    to meet.  */
402 static bool
valid_address_p(rtx op,struct address_info * ad,enum constraint_num constraint)403 valid_address_p (rtx op, struct address_info *ad,
404 		 enum constraint_num constraint)
405 {
406   address_eliminator eliminator (ad);
407 
408   /* Allow a memory OP if it matches CONSTRAINT, even if CONSTRAINT is more
409      forgiving than "m".
410      Need to extract memory from op for special memory constraint,
411      i.e. bcst_mem_operand in i386 backend.  */
412   if (MEM_P (extract_mem_from_operand (op))
413       && insn_extra_relaxed_memory_constraint (constraint)
414       && constraint_satisfied_p (op, constraint))
415     return true;
416 
417   return valid_address_p (ad->mode, *ad->outer, ad->as);
418 }
419 
420 /* For special_memory_operand, it could be false for MEM_P (op),
421    i.e. bcst_mem_operand in i386 backend.
422    Extract and return real memory operand or op.  */
423 rtx
extract_mem_from_operand(rtx op)424 extract_mem_from_operand (rtx op)
425 {
426   for (rtx x = op;; x = XEXP (x, 0))
427     {
428       if (MEM_P (x))
429 	return x;
430       if (GET_RTX_LENGTH (GET_CODE (x)) != 1
431 	  || GET_RTX_FORMAT (GET_CODE (x))[0] != 'e')
432 	break;
433     }
434   return op;
435 }
436 
437 /* Return true if the eliminated form of memory reference OP satisfies
438    extra (special) memory constraint CONSTRAINT.  */
439 static bool
satisfies_memory_constraint_p(rtx op,enum constraint_num constraint)440 satisfies_memory_constraint_p (rtx op, enum constraint_num constraint)
441 {
442   struct address_info ad;
443   rtx mem = extract_mem_from_operand (op);
444   if (!MEM_P (mem))
445     return false;
446 
447   decompose_mem_address (&ad, mem);
448   address_eliminator eliminator (&ad);
449   return constraint_satisfied_p (op, constraint);
450 }
451 
452 /* Return true if the eliminated form of address AD satisfies extra
453    address constraint CONSTRAINT.  */
454 static bool
satisfies_address_constraint_p(struct address_info * ad,enum constraint_num constraint)455 satisfies_address_constraint_p (struct address_info *ad,
456 				enum constraint_num constraint)
457 {
458   address_eliminator eliminator (ad);
459   return constraint_satisfied_p (*ad->outer, constraint);
460 }
461 
462 /* Return true if the eliminated form of address OP satisfies extra
463    address constraint CONSTRAINT.  */
464 static bool
satisfies_address_constraint_p(rtx op,enum constraint_num constraint)465 satisfies_address_constraint_p (rtx op, enum constraint_num constraint)
466 {
467   struct address_info ad;
468 
469   decompose_lea_address (&ad, &op);
470   return satisfies_address_constraint_p (&ad, constraint);
471 }
472 
473 /* Initiate equivalences for LRA.  As we keep original equivalences
474    before any elimination, we need to make copies otherwise any change
475    in insns might change the equivalences.  */
476 void
lra_init_equiv(void)477 lra_init_equiv (void)
478 {
479   ira_expand_reg_equiv ();
480   for (int i = FIRST_PSEUDO_REGISTER; i < max_reg_num (); i++)
481     {
482       rtx res;
483 
484       if ((res = ira_reg_equiv[i].memory) != NULL_RTX)
485 	ira_reg_equiv[i].memory = copy_rtx (res);
486       if ((res = ira_reg_equiv[i].invariant) != NULL_RTX)
487 	ira_reg_equiv[i].invariant = copy_rtx (res);
488     }
489 }
490 
491 static rtx loc_equivalence_callback (rtx, const_rtx, void *);
492 
493 /* Update equivalence for REGNO.  We need to this as the equivalence
494    might contain other pseudos which are changed by their
495    equivalences.  */
496 static void
update_equiv(int regno)497 update_equiv (int regno)
498 {
499   rtx x;
500 
501   if ((x = ira_reg_equiv[regno].memory) != NULL_RTX)
502     ira_reg_equiv[regno].memory
503       = simplify_replace_fn_rtx (x, NULL_RTX, loc_equivalence_callback,
504 				 NULL_RTX);
505   if ((x = ira_reg_equiv[regno].invariant) != NULL_RTX)
506     ira_reg_equiv[regno].invariant
507       = simplify_replace_fn_rtx (x, NULL_RTX, loc_equivalence_callback,
508 				 NULL_RTX);
509 }
510 
511 /* If we have decided to substitute X with another value, return that
512    value, otherwise return X.  */
513 static rtx
get_equiv(rtx x)514 get_equiv (rtx x)
515 {
516   int regno;
517   rtx res;
518 
519   if (! REG_P (x) || (regno = REGNO (x)) < FIRST_PSEUDO_REGISTER
520       || ! ira_reg_equiv[regno].defined_p
521       || ! ira_reg_equiv[regno].profitable_p
522       || lra_get_regno_hard_regno (regno) >= 0)
523     return x;
524   if ((res = ira_reg_equiv[regno].memory) != NULL_RTX)
525     {
526       if (targetm.cannot_substitute_mem_equiv_p (res))
527 	return x;
528       return res;
529     }
530   if ((res = ira_reg_equiv[regno].constant) != NULL_RTX)
531     return res;
532   if ((res = ira_reg_equiv[regno].invariant) != NULL_RTX)
533     return res;
534   gcc_unreachable ();
535 }
536 
537 /* If we have decided to substitute X with the equivalent value,
538    return that value after elimination for INSN, otherwise return
539    X.  */
540 static rtx
get_equiv_with_elimination(rtx x,rtx_insn * insn)541 get_equiv_with_elimination (rtx x, rtx_insn *insn)
542 {
543   rtx res = get_equiv (x);
544 
545   if (x == res || CONSTANT_P (res))
546     return res;
547   return lra_eliminate_regs_1 (insn, res, GET_MODE (res),
548 			       false, false, 0, true);
549 }
550 
551 /* Set up curr_operand_mode.  */
552 static void
init_curr_operand_mode(void)553 init_curr_operand_mode (void)
554 {
555   int nop = curr_static_id->n_operands;
556   for (int i = 0; i < nop; i++)
557     {
558       machine_mode mode = GET_MODE (*curr_id->operand_loc[i]);
559       if (mode == VOIDmode)
560 	{
561 	  /* The .md mode for address operands is the mode of the
562 	     addressed value rather than the mode of the address itself.  */
563 	  if (curr_id->icode >= 0 && curr_static_id->operand[i].is_address)
564 	    mode = Pmode;
565 	  else
566 	    mode = curr_static_id->operand[i].mode;
567 	}
568       curr_operand_mode[i] = mode;
569     }
570 }
571 
572 
573 
574 /* The page contains code to reuse input reloads.  */
575 
576 /* Structure describes input reload of the current insns.  */
577 struct input_reload
578 {
579   /* True for input reload of matched operands.  */
580   bool match_p;
581   /* Reloaded value.  */
582   rtx input;
583   /* Reload pseudo used.  */
584   rtx reg;
585 };
586 
587 /* The number of elements in the following array.  */
588 static int curr_insn_input_reloads_num;
589 /* Array containing info about input reloads.  It is used to find the
590    same input reload and reuse the reload pseudo in this case.	*/
591 static struct input_reload curr_insn_input_reloads[LRA_MAX_INSN_RELOADS];
592 
593 /* Initiate data concerning reuse of input reloads for the current
594    insn.  */
595 static void
init_curr_insn_input_reloads(void)596 init_curr_insn_input_reloads (void)
597 {
598   curr_insn_input_reloads_num = 0;
599 }
600 
601 /* The canonical form of an rtx inside a MEM is not necessarily the same as the
602    canonical form of the rtx outside the MEM.  Fix this up in the case that
603    we're reloading an address (and therefore pulling it outside a MEM).  */
604 static rtx
canonicalize_reload_addr(rtx addr)605 canonicalize_reload_addr (rtx addr)
606 {
607   subrtx_var_iterator::array_type array;
608   FOR_EACH_SUBRTX_VAR (iter, array, addr, NONCONST)
609     {
610       rtx x = *iter;
611       if (GET_CODE (x) == MULT && CONST_INT_P (XEXP (x, 1)))
612 	{
613 	  const HOST_WIDE_INT ci = INTVAL (XEXP (x, 1));
614 	  const int pwr2 = exact_log2 (ci);
615 	  if (pwr2 > 0)
616 	    {
617 	      /* Rewrite this to use a shift instead, which is canonical when
618 		 outside of a MEM.  */
619 	      PUT_CODE (x, ASHIFT);
620 	      XEXP (x, 1) = GEN_INT (pwr2);
621 	    }
622 	}
623     }
624 
625   return addr;
626 }
627 
628 /* Create a new pseudo using MODE, RCLASS, ORIGINAL or reuse an existing
629    reload pseudo.  Don't reuse an existing reload pseudo if IN_SUBREG_P
630    is true and the reused pseudo should be wrapped up in a SUBREG.
631    The result pseudo is returned through RESULT_REG.  Return TRUE if we
632    created a new pseudo, FALSE if we reused an existing reload pseudo.
633    Use TITLE to describe new registers for debug purposes.  */
634 static bool
get_reload_reg(enum op_type type,machine_mode mode,rtx original,enum reg_class rclass,bool in_subreg_p,const char * title,rtx * result_reg)635 get_reload_reg (enum op_type type, machine_mode mode, rtx original,
636 		enum reg_class rclass, bool in_subreg_p,
637 		const char *title, rtx *result_reg)
638 {
639   int i, regno;
640   enum reg_class new_class;
641   bool unique_p = false;
642 
643   if (type == OP_OUT)
644     {
645       /* Output reload registers tend to start out with a conservative
646 	 choice of register class.  Usually this is ALL_REGS, although
647 	 a target might narrow it (for performance reasons) through
648 	 targetm.preferred_reload_class.  It's therefore quite common
649 	 for a reload instruction to require a more restrictive class
650 	 than the class that was originally assigned to the reload register.
651 
652 	 In these situations, it's more efficient to refine the choice
653 	 of register class rather than create a second reload register.
654 	 This also helps to avoid cycling for registers that are only
655 	 used by reload instructions.  */
656       if (REG_P (original)
657 	  && (int) REGNO (original) >= new_regno_start
658 	  && INSN_UID (curr_insn) >= new_insn_uid_start
659 	  && in_class_p (original, rclass, &new_class, true))
660 	{
661 	  unsigned int regno = REGNO (original);
662 	  if (lra_dump_file != NULL)
663 	    {
664 	      fprintf (lra_dump_file, "	 Reuse r%d for output ", regno);
665 	      dump_value_slim (lra_dump_file, original, 1);
666 	    }
667 	  if (new_class != lra_get_allocno_class (regno))
668 	    lra_change_class (regno, new_class, ", change to", false);
669 	  if (lra_dump_file != NULL)
670 	    fprintf (lra_dump_file, "\n");
671 	  *result_reg = original;
672 	  return false;
673 	}
674       *result_reg
675 	= lra_create_new_reg_with_unique_value (mode, original, rclass, title);
676       return true;
677     }
678   /* Prevent reuse value of expression with side effects,
679      e.g. volatile memory.  */
680   if (! side_effects_p (original))
681     for (i = 0; i < curr_insn_input_reloads_num; i++)
682       {
683 	if (! curr_insn_input_reloads[i].match_p
684 	    && rtx_equal_p (curr_insn_input_reloads[i].input, original)
685 	    && in_class_p (curr_insn_input_reloads[i].reg, rclass, &new_class))
686 	  {
687 	    rtx reg = curr_insn_input_reloads[i].reg;
688 	    regno = REGNO (reg);
689 	    /* If input is equal to original and both are VOIDmode,
690 	       GET_MODE (reg) might be still different from mode.
691 	       Ensure we don't return *result_reg with wrong mode.  */
692 	    if (GET_MODE (reg) != mode)
693 	      {
694 		if (in_subreg_p)
695 		  continue;
696 		if (maybe_lt (GET_MODE_SIZE (GET_MODE (reg)),
697 			      GET_MODE_SIZE (mode)))
698 		  continue;
699 		reg = lowpart_subreg (mode, reg, GET_MODE (reg));
700 		if (reg == NULL_RTX || GET_CODE (reg) != SUBREG)
701 		  continue;
702 	      }
703 	    *result_reg = reg;
704 	    if (lra_dump_file != NULL)
705 	      {
706 		fprintf (lra_dump_file, "	 Reuse r%d for reload ", regno);
707 		dump_value_slim (lra_dump_file, original, 1);
708 	      }
709 	    if (new_class != lra_get_allocno_class (regno))
710 	      lra_change_class (regno, new_class, ", change to", false);
711 	    if (lra_dump_file != NULL)
712 	      fprintf (lra_dump_file, "\n");
713 	    return false;
714 	  }
715 	/* If we have an input reload with a different mode, make sure it
716 	   will get a different hard reg.  */
717 	else if (REG_P (original)
718 		 && REG_P (curr_insn_input_reloads[i].input)
719 		 && REGNO (original) == REGNO (curr_insn_input_reloads[i].input)
720 		 && (GET_MODE (original)
721 		     != GET_MODE (curr_insn_input_reloads[i].input)))
722 	  unique_p = true;
723       }
724   *result_reg = (unique_p
725 		 ? lra_create_new_reg_with_unique_value
726 		 : lra_create_new_reg) (mode, original, rclass, title);
727   lra_assert (curr_insn_input_reloads_num < LRA_MAX_INSN_RELOADS);
728   curr_insn_input_reloads[curr_insn_input_reloads_num].input = original;
729   curr_insn_input_reloads[curr_insn_input_reloads_num].match_p = false;
730   curr_insn_input_reloads[curr_insn_input_reloads_num++].reg = *result_reg;
731   return true;
732 }
733 
734 
735 /* The page contains major code to choose the current insn alternative
736    and generate reloads for it.	 */
737 
738 /* Return the offset from REGNO of the least significant register
739    in (reg:MODE REGNO).
740 
741    This function is used to tell whether two registers satisfy
742    a matching constraint.  (reg:MODE1 REGNO1) matches (reg:MODE2 REGNO2) if:
743 
744          REGNO1 + lra_constraint_offset (REGNO1, MODE1)
745 	 == REGNO2 + lra_constraint_offset (REGNO2, MODE2)  */
746 int
lra_constraint_offset(int regno,machine_mode mode)747 lra_constraint_offset (int regno, machine_mode mode)
748 {
749   lra_assert (regno < FIRST_PSEUDO_REGISTER);
750 
751   scalar_int_mode int_mode;
752   if (WORDS_BIG_ENDIAN
753       && is_a <scalar_int_mode> (mode, &int_mode)
754       && GET_MODE_SIZE (int_mode) > UNITS_PER_WORD)
755     return hard_regno_nregs (regno, mode) - 1;
756   return 0;
757 }
758 
759 /* Like rtx_equal_p except that it allows a REG and a SUBREG to match
760    if they are the same hard reg, and has special hacks for
761    auto-increment and auto-decrement.  This is specifically intended for
762    process_alt_operands to use in determining whether two operands
763    match.  X is the operand whose number is the lower of the two.
764 
765    It is supposed that X is the output operand and Y is the input
766    operand.  Y_HARD_REGNO is the final hard regno of register Y or
767    register in subreg Y as we know it now.  Otherwise, it is a
768    negative value.  */
769 static bool
operands_match_p(rtx x,rtx y,int y_hard_regno)770 operands_match_p (rtx x, rtx y, int y_hard_regno)
771 {
772   int i;
773   RTX_CODE code = GET_CODE (x);
774   const char *fmt;
775 
776   if (x == y)
777     return true;
778   if ((code == REG || (code == SUBREG && REG_P (SUBREG_REG (x))))
779       && (REG_P (y) || (GET_CODE (y) == SUBREG && REG_P (SUBREG_REG (y)))))
780     {
781       int j;
782 
783       i = get_hard_regno (x, false);
784       if (i < 0)
785 	goto slow;
786 
787       if ((j = y_hard_regno) < 0)
788 	goto slow;
789 
790       i += lra_constraint_offset (i, GET_MODE (x));
791       j += lra_constraint_offset (j, GET_MODE (y));
792 
793       return i == j;
794     }
795 
796   /* If two operands must match, because they are really a single
797      operand of an assembler insn, then two post-increments are invalid
798      because the assembler insn would increment only once.  On the
799      other hand, a post-increment matches ordinary indexing if the
800      post-increment is the output operand.  */
801   if (code == POST_DEC || code == POST_INC || code == POST_MODIFY)
802     return operands_match_p (XEXP (x, 0), y, y_hard_regno);
803 
804   /* Two pre-increments are invalid because the assembler insn would
805      increment only once.  On the other hand, a pre-increment matches
806      ordinary indexing if the pre-increment is the input operand.  */
807   if (GET_CODE (y) == PRE_DEC || GET_CODE (y) == PRE_INC
808       || GET_CODE (y) == PRE_MODIFY)
809     return operands_match_p (x, XEXP (y, 0), -1);
810 
811  slow:
812 
813   if (code == REG && REG_P (y))
814     return REGNO (x) == REGNO (y);
815 
816   if (code == REG && GET_CODE (y) == SUBREG && REG_P (SUBREG_REG (y))
817       && x == SUBREG_REG (y))
818     return true;
819   if (GET_CODE (y) == REG && code == SUBREG && REG_P (SUBREG_REG (x))
820       && SUBREG_REG (x) == y)
821     return true;
822 
823   /* Now we have disposed of all the cases in which different rtx
824      codes can match.  */
825   if (code != GET_CODE (y))
826     return false;
827 
828   /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent.  */
829   if (GET_MODE (x) != GET_MODE (y))
830     return false;
831 
832   switch (code)
833     {
834     CASE_CONST_UNIQUE:
835       return false;
836 
837     case CONST_VECTOR:
838       if (!same_vector_encodings_p (x, y))
839 	return false;
840       break;
841 
842     case LABEL_REF:
843       return label_ref_label (x) == label_ref_label (y);
844     case SYMBOL_REF:
845       return XSTR (x, 0) == XSTR (y, 0);
846 
847     default:
848       break;
849     }
850 
851   /* Compare the elements.  If any pair of corresponding elements fail
852      to match, return false for the whole things.  */
853 
854   fmt = GET_RTX_FORMAT (code);
855   for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
856     {
857       int val, j;
858       switch (fmt[i])
859 	{
860 	case 'w':
861 	  if (XWINT (x, i) != XWINT (y, i))
862 	    return false;
863 	  break;
864 
865 	case 'i':
866 	  if (XINT (x, i) != XINT (y, i))
867 	    return false;
868 	  break;
869 
870 	case 'p':
871 	  if (maybe_ne (SUBREG_BYTE (x), SUBREG_BYTE (y)))
872 	    return false;
873 	  break;
874 
875 	case 'e':
876 	  val = operands_match_p (XEXP (x, i), XEXP (y, i), -1);
877 	  if (val == 0)
878 	    return false;
879 	  break;
880 
881 	case '0':
882 	  break;
883 
884 	case 'E':
885 	  if (XVECLEN (x, i) != XVECLEN (y, i))
886 	    return false;
887 	  for (j = XVECLEN (x, i) - 1; j >= 0; --j)
888 	    {
889 	      val = operands_match_p (XVECEXP (x, i, j), XVECEXP (y, i, j), -1);
890 	      if (val == 0)
891 		return false;
892 	    }
893 	  break;
894 
895 	  /* It is believed that rtx's at this level will never
896 	     contain anything but integers and other rtx's, except for
897 	     within LABEL_REFs and SYMBOL_REFs.	 */
898 	default:
899 	  gcc_unreachable ();
900 	}
901     }
902   return true;
903 }
904 
905 /* True if X is a constant that can be forced into the constant pool.
906    MODE is the mode of the operand, or VOIDmode if not known.  */
907 #define CONST_POOL_OK_P(MODE, X)		\
908   ((MODE) != VOIDmode				\
909    && CONSTANT_P (X)				\
910    && GET_CODE (X) != HIGH			\
911    && GET_MODE_SIZE (MODE).is_constant ()	\
912    && !targetm.cannot_force_const_mem (MODE, X))
913 
914 /* True if C is a non-empty register class that has too few registers
915    to be safely used as a reload target class.	*/
916 #define SMALL_REGISTER_CLASS_P(C)		\
917   (ira_class_hard_regs_num [(C)] == 1		\
918    || (ira_class_hard_regs_num [(C)] >= 1	\
919        && targetm.class_likely_spilled_p (C)))
920 
921 /* If REG is a reload pseudo, try to make its class satisfying CL.  */
922 static void
narrow_reload_pseudo_class(rtx reg,enum reg_class cl)923 narrow_reload_pseudo_class (rtx reg, enum reg_class cl)
924 {
925   enum reg_class rclass;
926 
927   /* Do not make more accurate class from reloads generated.  They are
928      mostly moves with a lot of constraints.  Making more accurate
929      class may results in very narrow class and impossibility of find
930      registers for several reloads of one insn.	 */
931   if (INSN_UID (curr_insn) >= new_insn_uid_start)
932     return;
933   if (GET_CODE (reg) == SUBREG)
934     reg = SUBREG_REG (reg);
935   if (! REG_P (reg) || (int) REGNO (reg) < new_regno_start)
936     return;
937   if (in_class_p (reg, cl, &rclass) && rclass != cl)
938     lra_change_class (REGNO (reg), rclass, "      Change to", true);
939 }
940 
941 /* Searches X for any reference to a reg with the same value as REGNO,
942    returning the rtx of the reference found if any.  Otherwise,
943    returns NULL_RTX.  */
944 static rtx
regno_val_use_in(unsigned int regno,rtx x)945 regno_val_use_in (unsigned int regno, rtx x)
946 {
947   const char *fmt;
948   int i, j;
949   rtx tem;
950 
951   if (REG_P (x) && lra_reg_info[REGNO (x)].val == lra_reg_info[regno].val)
952     return x;
953 
954   fmt = GET_RTX_FORMAT (GET_CODE (x));
955   for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--)
956     {
957       if (fmt[i] == 'e')
958 	{
959 	  if ((tem = regno_val_use_in (regno, XEXP (x, i))))
960 	    return tem;
961 	}
962       else if (fmt[i] == 'E')
963 	for (j = XVECLEN (x, i) - 1; j >= 0; j--)
964 	  if ((tem = regno_val_use_in (regno , XVECEXP (x, i, j))))
965 	    return tem;
966     }
967 
968   return NULL_RTX;
969 }
970 
971 /* Return true if all current insn non-output operands except INS (it
972    has a negaitve end marker) do not use pseudos with the same value
973    as REGNO.  */
974 static bool
check_conflict_input_operands(int regno,signed char * ins)975 check_conflict_input_operands (int regno, signed char *ins)
976 {
977   int in;
978   int n_operands = curr_static_id->n_operands;
979 
980   for (int nop = 0; nop < n_operands; nop++)
981     if (! curr_static_id->operand[nop].is_operator
982 	&& curr_static_id->operand[nop].type != OP_OUT)
983       {
984 	for (int i = 0; (in = ins[i]) >= 0; i++)
985 	  if (in == nop)
986 	    break;
987 	if (in < 0
988 	    && regno_val_use_in (regno, *curr_id->operand_loc[nop]) != NULL_RTX)
989 	  return false;
990       }
991   return true;
992 }
993 
994 /* Generate reloads for matching OUT and INS (array of input operand
995    numbers with end marker -1) with reg class GOAL_CLASS, considering
996    output operands OUTS (similar array to INS) needing to be in different
997    registers.  Add input and output reloads correspondingly to the lists
998    *BEFORE and *AFTER.  OUT might be negative.  In this case we generate
999    input reloads for matched input operands INS.  EARLY_CLOBBER_P is a flag
1000    that the output operand is early clobbered for chosen alternative.  */
1001 static void
match_reload(signed char out,signed char * ins,signed char * outs,enum reg_class goal_class,rtx_insn ** before,rtx_insn ** after,bool early_clobber_p)1002 match_reload (signed char out, signed char *ins, signed char *outs,
1003 	      enum reg_class goal_class, rtx_insn **before,
1004 	      rtx_insn **after, bool early_clobber_p)
1005 {
1006   bool out_conflict;
1007   int i, in;
1008   rtx new_in_reg, new_out_reg, reg;
1009   machine_mode inmode, outmode;
1010   rtx in_rtx = *curr_id->operand_loc[ins[0]];
1011   rtx out_rtx = out < 0 ? in_rtx : *curr_id->operand_loc[out];
1012 
1013   inmode = curr_operand_mode[ins[0]];
1014   outmode = out < 0 ? inmode : curr_operand_mode[out];
1015   push_to_sequence (*before);
1016   if (inmode != outmode)
1017     {
1018       /* process_alt_operands has already checked that the mode sizes
1019 	 are ordered.  */
1020       if (partial_subreg_p (outmode, inmode))
1021 	{
1022 	  reg = new_in_reg
1023 	    = lra_create_new_reg_with_unique_value (inmode, in_rtx,
1024 						    goal_class, "");
1025 	  new_out_reg = gen_lowpart_SUBREG (outmode, reg);
1026 	  LRA_SUBREG_P (new_out_reg) = 1;
1027 	  /* If the input reg is dying here, we can use the same hard
1028 	     register for REG and IN_RTX.  We do it only for original
1029 	     pseudos as reload pseudos can die although original
1030 	     pseudos still live where reload pseudos dies.  */
1031 	  if (REG_P (in_rtx) && (int) REGNO (in_rtx) < lra_new_regno_start
1032 	      && find_regno_note (curr_insn, REG_DEAD, REGNO (in_rtx))
1033 	      && (!early_clobber_p
1034 		  || check_conflict_input_operands(REGNO (in_rtx), ins)))
1035 	    lra_assign_reg_val (REGNO (in_rtx), REGNO (reg));
1036 	}
1037       else
1038 	{
1039 	  reg = new_out_reg
1040 	    = lra_create_new_reg_with_unique_value (outmode, out_rtx,
1041 						    goal_class, "");
1042 	  new_in_reg = gen_lowpart_SUBREG (inmode, reg);
1043 	  /* NEW_IN_REG is non-paradoxical subreg.  We don't want
1044 	     NEW_OUT_REG living above.  We add clobber clause for
1045 	     this.  This is just a temporary clobber.  We can remove
1046 	     it at the end of LRA work.  */
1047 	  rtx_insn *clobber = emit_clobber (new_out_reg);
1048 	  LRA_TEMP_CLOBBER_P (PATTERN (clobber)) = 1;
1049 	  LRA_SUBREG_P (new_in_reg) = 1;
1050 	  if (GET_CODE (in_rtx) == SUBREG)
1051 	    {
1052 	      rtx subreg_reg = SUBREG_REG (in_rtx);
1053 
1054 	      /* If SUBREG_REG is dying here and sub-registers IN_RTX
1055 		 and NEW_IN_REG are similar, we can use the same hard
1056 		 register for REG and SUBREG_REG.  */
1057 	      if (REG_P (subreg_reg)
1058 		  && (int) REGNO (subreg_reg) < lra_new_regno_start
1059 		  && GET_MODE (subreg_reg) == outmode
1060 		  && known_eq (SUBREG_BYTE (in_rtx), SUBREG_BYTE (new_in_reg))
1061 		  && find_regno_note (curr_insn, REG_DEAD, REGNO (subreg_reg))
1062 		  && (! early_clobber_p
1063 		      || check_conflict_input_operands (REGNO (subreg_reg),
1064 							ins)))
1065 		lra_assign_reg_val (REGNO (subreg_reg), REGNO (reg));
1066 	    }
1067 	}
1068     }
1069   else
1070     {
1071       /* Pseudos have values -- see comments for lra_reg_info.
1072 	 Different pseudos with the same value do not conflict even if
1073 	 they live in the same place.  When we create a pseudo we
1074 	 assign value of original pseudo (if any) from which we
1075 	 created the new pseudo.  If we create the pseudo from the
1076 	 input pseudo, the new pseudo will have no conflict with the
1077 	 input pseudo which is wrong when the input pseudo lives after
1078 	 the insn and as the new pseudo value is changed by the insn
1079 	 output.  Therefore we create the new pseudo from the output
1080 	 except the case when we have single matched dying input
1081 	 pseudo.
1082 
1083 	 We cannot reuse the current output register because we might
1084 	 have a situation like "a <- a op b", where the constraints
1085 	 force the second input operand ("b") to match the output
1086 	 operand ("a").  "b" must then be copied into a new register
1087 	 so that it doesn't clobber the current value of "a".
1088 
1089 	 We cannot use the same value if the output pseudo is
1090 	 early clobbered or the input pseudo is mentioned in the
1091 	 output, e.g. as an address part in memory, because
1092 	 output reload will actually extend the pseudo liveness.
1093 	 We don't care about eliminable hard regs here as we are
1094 	 interesting only in pseudos.  */
1095 
1096       /* Matching input's register value is the same as one of the other
1097 	 output operand.  Output operands in a parallel insn must be in
1098 	 different registers.  */
1099       out_conflict = false;
1100       if (REG_P (in_rtx))
1101 	{
1102 	  for (i = 0; outs[i] >= 0; i++)
1103 	    {
1104 	      rtx other_out_rtx = *curr_id->operand_loc[outs[i]];
1105 	      if (REG_P (other_out_rtx)
1106 		  && (regno_val_use_in (REGNO (in_rtx), other_out_rtx)
1107 		      != NULL_RTX))
1108 		{
1109 		  out_conflict = true;
1110 		  break;
1111 		}
1112 	    }
1113 	}
1114 
1115       new_in_reg = new_out_reg
1116 	= (! early_clobber_p && ins[1] < 0 && REG_P (in_rtx)
1117 	   && (int) REGNO (in_rtx) < lra_new_regno_start
1118 	   && find_regno_note (curr_insn, REG_DEAD, REGNO (in_rtx))
1119 	   && (! early_clobber_p
1120 	       || check_conflict_input_operands (REGNO (in_rtx), ins))
1121 	   && (out < 0
1122 	       || regno_val_use_in (REGNO (in_rtx), out_rtx) == NULL_RTX)
1123 	   && !out_conflict
1124 	   ? lra_create_new_reg (inmode, in_rtx, goal_class, "")
1125 	   : lra_create_new_reg_with_unique_value (outmode, out_rtx,
1126 						   goal_class, ""));
1127     }
1128   /* In operand can be got from transformations before processing insn
1129      constraints.  One example of such transformations is subreg
1130      reloading (see function simplify_operand_subreg).  The new
1131      pseudos created by the transformations might have inaccurate
1132      class (ALL_REGS) and we should make their classes more
1133      accurate.  */
1134   narrow_reload_pseudo_class (in_rtx, goal_class);
1135   lra_emit_move (copy_rtx (new_in_reg), in_rtx);
1136   *before = get_insns ();
1137   end_sequence ();
1138   /* Add the new pseudo to consider values of subsequent input reload
1139      pseudos.  */
1140   lra_assert (curr_insn_input_reloads_num < LRA_MAX_INSN_RELOADS);
1141   curr_insn_input_reloads[curr_insn_input_reloads_num].input = in_rtx;
1142   curr_insn_input_reloads[curr_insn_input_reloads_num].match_p = true;
1143   curr_insn_input_reloads[curr_insn_input_reloads_num++].reg = new_in_reg;
1144   for (i = 0; (in = ins[i]) >= 0; i++)
1145     if (GET_MODE (*curr_id->operand_loc[in]) == VOIDmode
1146 	|| GET_MODE (new_in_reg) == GET_MODE (*curr_id->operand_loc[in]))
1147       *curr_id->operand_loc[in] = new_in_reg;
1148     else
1149       {
1150 	lra_assert
1151 	  (GET_MODE (new_out_reg) == GET_MODE (*curr_id->operand_loc[in]));
1152 	*curr_id->operand_loc[in] = new_out_reg;
1153       }
1154   lra_update_dups (curr_id, ins);
1155   if (out < 0)
1156     return;
1157   /* See a comment for the input operand above.  */
1158   narrow_reload_pseudo_class (out_rtx, goal_class);
1159   if (find_reg_note (curr_insn, REG_UNUSED, out_rtx) == NULL_RTX)
1160     {
1161       reg = SUBREG_P (out_rtx) ? SUBREG_REG (out_rtx) : out_rtx;
1162       start_sequence ();
1163       /* If we had strict_low_part, use it also in reload to keep other
1164 	 parts unchanged but do it only for regs as strict_low_part
1165 	 has no sense for memory and probably there is no insn pattern
1166 	 to match the reload insn in memory case.  */
1167       if (out >= 0 && curr_static_id->operand[out].strict_low && REG_P (reg))
1168 	out_rtx = gen_rtx_STRICT_LOW_PART (VOIDmode, out_rtx);
1169       lra_emit_move (out_rtx, copy_rtx (new_out_reg));
1170       emit_insn (*after);
1171       *after = get_insns ();
1172       end_sequence ();
1173     }
1174   *curr_id->operand_loc[out] = new_out_reg;
1175   lra_update_dup (curr_id, out);
1176 }
1177 
1178 /* Return register class which is union of all reg classes in insn
1179    constraint alternative string starting with P.  */
1180 static enum reg_class
reg_class_from_constraints(const char * p)1181 reg_class_from_constraints (const char *p)
1182 {
1183   int c, len;
1184   enum reg_class op_class = NO_REGS;
1185 
1186   do
1187     switch ((c = *p, len = CONSTRAINT_LEN (c, p)), c)
1188       {
1189       case '#':
1190       case ',':
1191 	return op_class;
1192 
1193       case 'g':
1194 	op_class = reg_class_subunion[op_class][GENERAL_REGS];
1195 	break;
1196 
1197       default:
1198 	enum constraint_num cn = lookup_constraint (p);
1199 	enum reg_class cl = reg_class_for_constraint (cn);
1200 	if (cl == NO_REGS)
1201 	  {
1202 	    if (insn_extra_address_constraint (cn))
1203 	      op_class
1204 		= (reg_class_subunion
1205 		   [op_class][base_reg_class (VOIDmode, ADDR_SPACE_GENERIC,
1206 					      ADDRESS, SCRATCH)]);
1207 	    break;
1208 	  }
1209 
1210 	op_class = reg_class_subunion[op_class][cl];
1211  	break;
1212       }
1213   while ((p += len), c);
1214   return op_class;
1215 }
1216 
1217 /* If OP is a register, return the class of the register as per
1218    get_reg_class, otherwise return NO_REGS.  */
1219 static inline enum reg_class
get_op_class(rtx op)1220 get_op_class (rtx op)
1221 {
1222   return REG_P (op) ? get_reg_class (REGNO (op)) : NO_REGS;
1223 }
1224 
1225 /* Return generated insn mem_pseudo:=val if TO_P or val:=mem_pseudo
1226    otherwise.  If modes of MEM_PSEUDO and VAL are different, use
1227    SUBREG for VAL to make them equal.  */
1228 static rtx_insn *
emit_spill_move(bool to_p,rtx mem_pseudo,rtx val)1229 emit_spill_move (bool to_p, rtx mem_pseudo, rtx val)
1230 {
1231   if (GET_MODE (mem_pseudo) != GET_MODE (val))
1232     {
1233       /* Usually size of mem_pseudo is greater than val size but in
1234 	 rare cases it can be less as it can be defined by target
1235 	 dependent macro HARD_REGNO_CALLER_SAVE_MODE.  */
1236       if (! MEM_P (val))
1237 	{
1238 	  val = gen_lowpart_SUBREG (GET_MODE (mem_pseudo),
1239 				    GET_CODE (val) == SUBREG
1240 				    ? SUBREG_REG (val) : val);
1241 	  LRA_SUBREG_P (val) = 1;
1242 	}
1243       else
1244 	{
1245 	  mem_pseudo = gen_lowpart_SUBREG (GET_MODE (val), mem_pseudo);
1246 	  LRA_SUBREG_P (mem_pseudo) = 1;
1247 	}
1248     }
1249   return to_p ? gen_move_insn (mem_pseudo, val)
1250 	      : gen_move_insn (val, mem_pseudo);
1251 }
1252 
1253 /* Process a special case insn (register move), return true if we
1254    don't need to process it anymore.  INSN should be a single set
1255    insn.  Set up that RTL was changed through CHANGE_P and that hook
1256    TARGET_SECONDARY_MEMORY_NEEDED says to use secondary memory through
1257    SEC_MEM_P.  */
1258 static bool
check_and_process_move(bool * change_p,bool * sec_mem_p ATTRIBUTE_UNUSED)1259 check_and_process_move (bool *change_p, bool *sec_mem_p ATTRIBUTE_UNUSED)
1260 {
1261   int sregno, dregno;
1262   rtx dest, src, dreg, sreg, new_reg, scratch_reg;
1263   rtx_insn *before;
1264   enum reg_class dclass, sclass, secondary_class;
1265   secondary_reload_info sri;
1266 
1267   lra_assert (curr_insn_set != NULL_RTX);
1268   dreg = dest = SET_DEST (curr_insn_set);
1269   sreg = src = SET_SRC (curr_insn_set);
1270   if (GET_CODE (dest) == SUBREG)
1271     dreg = SUBREG_REG (dest);
1272   if (GET_CODE (src) == SUBREG)
1273     sreg = SUBREG_REG (src);
1274   if (! (REG_P (dreg) || MEM_P (dreg)) || ! (REG_P (sreg) || MEM_P (sreg)))
1275     return false;
1276   sclass = dclass = NO_REGS;
1277   if (REG_P (dreg))
1278     dclass = get_reg_class (REGNO (dreg));
1279   gcc_assert (dclass < LIM_REG_CLASSES);
1280   if (dclass == ALL_REGS)
1281     /* ALL_REGS is used for new pseudos created by transformations
1282        like reload of SUBREG_REG (see function
1283        simplify_operand_subreg).  We don't know their class yet.  We
1284        should figure out the class from processing the insn
1285        constraints not in this fast path function.  Even if ALL_REGS
1286        were a right class for the pseudo, secondary_... hooks usually
1287        are not define for ALL_REGS.  */
1288     return false;
1289   if (REG_P (sreg))
1290     sclass = get_reg_class (REGNO (sreg));
1291   gcc_assert (sclass < LIM_REG_CLASSES);
1292   if (sclass == ALL_REGS)
1293     /* See comments above.  */
1294     return false;
1295   if (sclass == NO_REGS && dclass == NO_REGS)
1296     return false;
1297   if (targetm.secondary_memory_needed (GET_MODE (src), sclass, dclass)
1298       && ((sclass != NO_REGS && dclass != NO_REGS)
1299 	  || (GET_MODE (src)
1300 	      != targetm.secondary_memory_needed_mode (GET_MODE (src)))))
1301     {
1302       *sec_mem_p = true;
1303       return false;
1304     }
1305   if (! REG_P (dreg) || ! REG_P (sreg))
1306     return false;
1307   sri.prev_sri = NULL;
1308   sri.icode = CODE_FOR_nothing;
1309   sri.extra_cost = 0;
1310   secondary_class = NO_REGS;
1311   /* Set up hard register for a reload pseudo for hook
1312      secondary_reload because some targets just ignore unassigned
1313      pseudos in the hook.  */
1314   if (dclass != NO_REGS && lra_get_regno_hard_regno (REGNO (dreg)) < 0)
1315     {
1316       dregno = REGNO (dreg);
1317       reg_renumber[dregno] = ira_class_hard_regs[dclass][0];
1318     }
1319   else
1320     dregno = -1;
1321   if (sclass != NO_REGS && lra_get_regno_hard_regno (REGNO (sreg)) < 0)
1322     {
1323       sregno = REGNO (sreg);
1324       reg_renumber[sregno] = ira_class_hard_regs[sclass][0];
1325     }
1326   else
1327     sregno = -1;
1328   if (sclass != NO_REGS)
1329     secondary_class
1330       = (enum reg_class) targetm.secondary_reload (false, dest,
1331 						   (reg_class_t) sclass,
1332 						   GET_MODE (src), &sri);
1333   if (sclass == NO_REGS
1334       || ((secondary_class != NO_REGS || sri.icode != CODE_FOR_nothing)
1335 	  && dclass != NO_REGS))
1336     {
1337       enum reg_class old_sclass = secondary_class;
1338       secondary_reload_info old_sri = sri;
1339 
1340       sri.prev_sri = NULL;
1341       sri.icode = CODE_FOR_nothing;
1342       sri.extra_cost = 0;
1343       secondary_class
1344 	= (enum reg_class) targetm.secondary_reload (true, src,
1345 						     (reg_class_t) dclass,
1346 						     GET_MODE (src), &sri);
1347       /* Check the target hook consistency.  */
1348       lra_assert
1349 	((secondary_class == NO_REGS && sri.icode == CODE_FOR_nothing)
1350 	 || (old_sclass == NO_REGS && old_sri.icode == CODE_FOR_nothing)
1351 	 || (secondary_class == old_sclass && sri.icode == old_sri.icode));
1352     }
1353   if (sregno >= 0)
1354     reg_renumber [sregno] = -1;
1355   if (dregno >= 0)
1356     reg_renumber [dregno] = -1;
1357   if (secondary_class == NO_REGS && sri.icode == CODE_FOR_nothing)
1358     return false;
1359   *change_p = true;
1360   new_reg = NULL_RTX;
1361   if (secondary_class != NO_REGS)
1362     new_reg = lra_create_new_reg_with_unique_value (GET_MODE (src), NULL_RTX,
1363 						    secondary_class,
1364 						    "secondary");
1365   start_sequence ();
1366   if (sri.icode == CODE_FOR_nothing)
1367     lra_emit_move (new_reg, src);
1368   else
1369     {
1370       enum reg_class scratch_class;
1371 
1372       scratch_class = (reg_class_from_constraints
1373 		       (insn_data[sri.icode].operand[2].constraint));
1374       scratch_reg = (lra_create_new_reg_with_unique_value
1375 		     (insn_data[sri.icode].operand[2].mode, NULL_RTX,
1376 		      scratch_class, "scratch"));
1377       emit_insn (GEN_FCN (sri.icode) (new_reg != NULL_RTX ? new_reg : dest,
1378 				      src, scratch_reg));
1379     }
1380   before = get_insns ();
1381   end_sequence ();
1382   lra_process_new_insns (curr_insn, before, NULL, "Inserting the move");
1383   if (new_reg != NULL_RTX)
1384     SET_SRC (curr_insn_set) = new_reg;
1385   else
1386     {
1387       if (lra_dump_file != NULL)
1388 	{
1389 	  fprintf (lra_dump_file, "Deleting move %u\n", INSN_UID (curr_insn));
1390 	  dump_insn_slim (lra_dump_file, curr_insn);
1391 	}
1392       lra_set_insn_deleted (curr_insn);
1393       return true;
1394     }
1395   return false;
1396 }
1397 
1398 /* The following data describe the result of process_alt_operands.
1399    The data are used in curr_insn_transform to generate reloads.  */
1400 
1401 /* The chosen reg classes which should be used for the corresponding
1402    operands.  */
1403 static enum reg_class goal_alt[MAX_RECOG_OPERANDS];
1404 /* True if the operand should be the same as another operand and that
1405    other operand does not need a reload.  */
1406 static bool goal_alt_match_win[MAX_RECOG_OPERANDS];
1407 /* True if the operand does not need a reload.	*/
1408 static bool goal_alt_win[MAX_RECOG_OPERANDS];
1409 /* True if the operand can be offsetable memory.  */
1410 static bool goal_alt_offmemok[MAX_RECOG_OPERANDS];
1411 /* The number of an operand to which given operand can be matched to.  */
1412 static int goal_alt_matches[MAX_RECOG_OPERANDS];
1413 /* The number of elements in the following array.  */
1414 static int goal_alt_dont_inherit_ops_num;
1415 /* Numbers of operands whose reload pseudos should not be inherited.  */
1416 static int goal_alt_dont_inherit_ops[MAX_RECOG_OPERANDS];
1417 /* True if the insn commutative operands should be swapped.  */
1418 static bool goal_alt_swapped;
1419 /* The chosen insn alternative.	 */
1420 static int goal_alt_number;
1421 
1422 /* True if the corresponding operand is the result of an equivalence
1423    substitution.  */
1424 static bool equiv_substition_p[MAX_RECOG_OPERANDS];
1425 
1426 /* The following five variables are used to choose the best insn
1427    alternative.	 They reflect final characteristics of the best
1428    alternative.	 */
1429 
1430 /* Number of necessary reloads and overall cost reflecting the
1431    previous value and other unpleasantness of the best alternative.  */
1432 static int best_losers, best_overall;
1433 /* Overall number hard registers used for reloads.  For example, on
1434    some targets we need 2 general registers to reload DFmode and only
1435    one floating point register.	 */
1436 static int best_reload_nregs;
1437 /* Overall number reflecting distances of previous reloading the same
1438    value.  The distances are counted from the current BB start.  It is
1439    used to improve inheritance chances.  */
1440 static int best_reload_sum;
1441 
1442 /* True if the current insn should have no correspondingly input or
1443    output reloads.  */
1444 static bool no_input_reloads_p, no_output_reloads_p;
1445 
1446 /* True if we swapped the commutative operands in the current
1447    insn.  */
1448 static int curr_swapped;
1449 
1450 /* if CHECK_ONLY_P is false, arrange for address element *LOC to be a
1451    register of class CL.  Add any input reloads to list BEFORE.  AFTER
1452    is nonnull if *LOC is an automodified value; handle that case by
1453    adding the required output reloads to list AFTER.  Return true if
1454    the RTL was changed.
1455 
1456    if CHECK_ONLY_P is true, check that the *LOC is a correct address
1457    register.  Return false if the address register is correct.  */
1458 static bool
process_addr_reg(rtx * loc,bool check_only_p,rtx_insn ** before,rtx_insn ** after,enum reg_class cl)1459 process_addr_reg (rtx *loc, bool check_only_p, rtx_insn **before, rtx_insn **after,
1460 		  enum reg_class cl)
1461 {
1462   int regno;
1463   enum reg_class rclass, new_class;
1464   rtx reg;
1465   rtx new_reg;
1466   machine_mode mode;
1467   bool subreg_p, before_p = false;
1468 
1469   subreg_p = GET_CODE (*loc) == SUBREG;
1470   if (subreg_p)
1471     {
1472       reg = SUBREG_REG (*loc);
1473       mode = GET_MODE (reg);
1474 
1475       /* For mode with size bigger than ptr_mode, there unlikely to be "mov"
1476 	 between two registers with different classes, but there normally will
1477 	 be "mov" which transfers element of vector register into the general
1478 	 register, and this normally will be a subreg which should be reloaded
1479 	 as a whole.  This is particularly likely to be triggered when
1480 	 -fno-split-wide-types specified.  */
1481       if (!REG_P (reg)
1482 	  || in_class_p (reg, cl, &new_class)
1483 	  || known_le (GET_MODE_SIZE (mode), GET_MODE_SIZE (ptr_mode)))
1484        loc = &SUBREG_REG (*loc);
1485     }
1486 
1487   reg = *loc;
1488   mode = GET_MODE (reg);
1489   if (! REG_P (reg))
1490     {
1491       if (check_only_p)
1492 	return true;
1493       /* Always reload memory in an address even if the target supports
1494 	 such addresses.  */
1495       new_reg = lra_create_new_reg_with_unique_value (mode, reg, cl, "address");
1496       before_p = true;
1497     }
1498   else
1499     {
1500       regno = REGNO (reg);
1501       rclass = get_reg_class (regno);
1502       if (! check_only_p
1503 	  && (*loc = get_equiv_with_elimination (reg, curr_insn)) != reg)
1504 	{
1505 	  if (lra_dump_file != NULL)
1506 	    {
1507 	      fprintf (lra_dump_file,
1508 		       "Changing pseudo %d in address of insn %u on equiv ",
1509 		       REGNO (reg), INSN_UID (curr_insn));
1510 	      dump_value_slim (lra_dump_file, *loc, 1);
1511 	      fprintf (lra_dump_file, "\n");
1512 	    }
1513 	  *loc = copy_rtx (*loc);
1514 	}
1515       if (*loc != reg || ! in_class_p (reg, cl, &new_class))
1516 	{
1517 	  if (check_only_p)
1518 	    return true;
1519 	  reg = *loc;
1520 	  if (get_reload_reg (after == NULL ? OP_IN : OP_INOUT,
1521 			      mode, reg, cl, subreg_p, "address", &new_reg))
1522 	    before_p = true;
1523 	}
1524       else if (new_class != NO_REGS && rclass != new_class)
1525 	{
1526 	  if (check_only_p)
1527 	    return true;
1528 	  lra_change_class (regno, new_class, "	   Change to", true);
1529 	  return false;
1530 	}
1531       else
1532 	return false;
1533     }
1534   if (before_p)
1535     {
1536       push_to_sequence (*before);
1537       lra_emit_move (new_reg, reg);
1538       *before = get_insns ();
1539       end_sequence ();
1540     }
1541   *loc = new_reg;
1542   if (after != NULL)
1543     {
1544       start_sequence ();
1545       lra_emit_move (before_p ? copy_rtx (reg) : reg, new_reg);
1546       emit_insn (*after);
1547       *after = get_insns ();
1548       end_sequence ();
1549     }
1550   return true;
1551 }
1552 
1553 /* Insert move insn in simplify_operand_subreg. BEFORE returns
1554    the insn to be inserted before curr insn. AFTER returns the
1555    the insn to be inserted after curr insn.  ORIGREG and NEWREG
1556    are the original reg and new reg for reload.  */
1557 static void
insert_move_for_subreg(rtx_insn ** before,rtx_insn ** after,rtx origreg,rtx newreg)1558 insert_move_for_subreg (rtx_insn **before, rtx_insn **after, rtx origreg,
1559 			rtx newreg)
1560 {
1561   if (before)
1562     {
1563       push_to_sequence (*before);
1564       lra_emit_move (newreg, origreg);
1565       *before = get_insns ();
1566       end_sequence ();
1567     }
1568   if (after)
1569     {
1570       start_sequence ();
1571       lra_emit_move (origreg, newreg);
1572       emit_insn (*after);
1573       *after = get_insns ();
1574       end_sequence ();
1575     }
1576 }
1577 
1578 static int valid_address_p (machine_mode mode, rtx addr, addr_space_t as);
1579 static bool process_address (int, bool, rtx_insn **, rtx_insn **);
1580 
1581 /* Make reloads for subreg in operand NOP with internal subreg mode
1582    REG_MODE, add new reloads for further processing.  Return true if
1583    any change was done.  */
1584 static bool
simplify_operand_subreg(int nop,machine_mode reg_mode)1585 simplify_operand_subreg (int nop, machine_mode reg_mode)
1586 {
1587   int hard_regno, inner_hard_regno;
1588   rtx_insn *before, *after;
1589   machine_mode mode, innermode;
1590   rtx reg, new_reg;
1591   rtx operand = *curr_id->operand_loc[nop];
1592   enum reg_class regclass;
1593   enum op_type type;
1594 
1595   before = after = NULL;
1596 
1597   if (GET_CODE (operand) != SUBREG)
1598     return false;
1599 
1600   mode = GET_MODE (operand);
1601   reg = SUBREG_REG (operand);
1602   innermode = GET_MODE (reg);
1603   type = curr_static_id->operand[nop].type;
1604   if (MEM_P (reg))
1605     {
1606       const bool addr_was_valid
1607 	= valid_address_p (innermode, XEXP (reg, 0), MEM_ADDR_SPACE (reg));
1608       alter_subreg (curr_id->operand_loc[nop], false);
1609       rtx subst = *curr_id->operand_loc[nop];
1610       lra_assert (MEM_P (subst));
1611       const bool addr_is_valid = valid_address_p (GET_MODE (subst),
1612 						  XEXP (subst, 0),
1613 						  MEM_ADDR_SPACE (subst));
1614       if (!addr_was_valid
1615 	  || addr_is_valid
1616 	  || ((get_constraint_type (lookup_constraint
1617 				    (curr_static_id->operand[nop].constraint))
1618 	       != CT_SPECIAL_MEMORY)
1619 	      /* We still can reload address and if the address is
1620 		 valid, we can remove subreg without reloading its
1621 		 inner memory.  */
1622 	      && valid_address_p (GET_MODE (subst),
1623 				  regno_reg_rtx
1624 				  [ira_class_hard_regs
1625 				   [base_reg_class (GET_MODE (subst),
1626 						    MEM_ADDR_SPACE (subst),
1627 						    ADDRESS, SCRATCH)][0]],
1628 				  MEM_ADDR_SPACE (subst))))
1629 	{
1630 	  /* If we change the address for a paradoxical subreg of memory, the
1631 	     new address might violate the necessary alignment or the access
1632 	     might be slow; take this into consideration.  We need not worry
1633 	     about accesses beyond allocated memory for paradoxical memory
1634 	     subregs as we don't substitute such equiv memory (see processing
1635 	     equivalences in function lra_constraints) and because for spilled
1636 	     pseudos we allocate stack memory enough for the biggest
1637 	     corresponding paradoxical subreg.
1638 
1639 	     However, do not blindly simplify a (subreg (mem ...)) for
1640 	     WORD_REGISTER_OPERATIONS targets as this may lead to loading junk
1641 	     data into a register when the inner is narrower than outer or
1642 	     missing important data from memory when the inner is wider than
1643 	     outer.  This rule only applies to modes that are no wider than
1644 	     a word.
1645 
1646 	     If valid memory becomes invalid after subreg elimination
1647 	     and address might be different we still have to reload
1648 	     memory.
1649 	  */
1650 	  if ((! addr_was_valid
1651 	       || addr_is_valid
1652 	       || known_eq (GET_MODE_SIZE (mode), GET_MODE_SIZE (innermode)))
1653 	      && !(maybe_ne (GET_MODE_PRECISION (mode),
1654 			     GET_MODE_PRECISION (innermode))
1655 		   && known_le (GET_MODE_SIZE (mode), UNITS_PER_WORD)
1656 		   && known_le (GET_MODE_SIZE (innermode), UNITS_PER_WORD)
1657 		   && WORD_REGISTER_OPERATIONS)
1658 	      && (!(MEM_ALIGN (subst) < GET_MODE_ALIGNMENT (mode)
1659 		    && targetm.slow_unaligned_access (mode, MEM_ALIGN (subst)))
1660 		  || (MEM_ALIGN (reg) < GET_MODE_ALIGNMENT (innermode)
1661 		      && targetm.slow_unaligned_access (innermode,
1662 							MEM_ALIGN (reg)))))
1663 	    return true;
1664 
1665 	  *curr_id->operand_loc[nop] = operand;
1666 
1667 	  /* But if the address was not valid, we cannot reload the MEM without
1668 	     reloading the address first.  */
1669 	  if (!addr_was_valid)
1670 	    process_address (nop, false, &before, &after);
1671 
1672 	  /* INNERMODE is fast, MODE slow.  Reload the mem in INNERMODE.  */
1673 	  enum reg_class rclass
1674 	    = (enum reg_class) targetm.preferred_reload_class (reg, ALL_REGS);
1675 	  if (get_reload_reg (curr_static_id->operand[nop].type, innermode,
1676 			      reg, rclass, TRUE, "slow/invalid mem", &new_reg))
1677 	    {
1678 	      bool insert_before, insert_after;
1679 	      bitmap_set_bit (&lra_subreg_reload_pseudos, REGNO (new_reg));
1680 
1681 	      insert_before = (type != OP_OUT
1682 			       || partial_subreg_p (mode, innermode));
1683 	      insert_after = type != OP_IN;
1684 	      insert_move_for_subreg (insert_before ? &before : NULL,
1685 				      insert_after ? &after : NULL,
1686 				      reg, new_reg);
1687 	    }
1688 	  SUBREG_REG (operand) = new_reg;
1689 
1690 	  /* Convert to MODE.  */
1691 	  reg = operand;
1692 	  rclass
1693 	    = (enum reg_class) targetm.preferred_reload_class (reg, ALL_REGS);
1694 	  if (get_reload_reg (curr_static_id->operand[nop].type, mode, reg,
1695 			      rclass, TRUE, "slow/invalid mem", &new_reg))
1696 	    {
1697 	      bool insert_before, insert_after;
1698 	      bitmap_set_bit (&lra_subreg_reload_pseudos, REGNO (new_reg));
1699 
1700 	      insert_before = type != OP_OUT;
1701 	      insert_after = type != OP_IN;
1702 	      insert_move_for_subreg (insert_before ? &before : NULL,
1703 				      insert_after ? &after : NULL,
1704 				      reg, new_reg);
1705 	    }
1706 	  *curr_id->operand_loc[nop] = new_reg;
1707 	  lra_process_new_insns (curr_insn, before, after,
1708 				 "Inserting slow/invalid mem reload");
1709 	  return true;
1710 	}
1711 
1712       /* If the address was valid and became invalid, prefer to reload
1713 	 the memory.  Typical case is when the index scale should
1714 	 correspond the memory.  */
1715       *curr_id->operand_loc[nop] = operand;
1716       /* Do not return false here as the MEM_P (reg) will be processed
1717 	 later in this function.  */
1718     }
1719   else if (REG_P (reg) && REGNO (reg) < FIRST_PSEUDO_REGISTER)
1720     {
1721       alter_subreg (curr_id->operand_loc[nop], false);
1722       return true;
1723     }
1724   else if (CONSTANT_P (reg))
1725     {
1726       /* Try to simplify subreg of constant.  It is usually result of
1727 	 equivalence substitution.  */
1728       if (innermode == VOIDmode
1729 	  && (innermode = original_subreg_reg_mode[nop]) == VOIDmode)
1730 	innermode = curr_static_id->operand[nop].mode;
1731       if ((new_reg = simplify_subreg (mode, reg, innermode,
1732 				      SUBREG_BYTE (operand))) != NULL_RTX)
1733 	{
1734 	  *curr_id->operand_loc[nop] = new_reg;
1735 	  return true;
1736 	}
1737     }
1738   /* Put constant into memory when we have mixed modes.  It generates
1739      a better code in most cases as it does not need a secondary
1740      reload memory.  It also prevents LRA looping when LRA is using
1741      secondary reload memory again and again.  */
1742   if (CONSTANT_P (reg) && CONST_POOL_OK_P (reg_mode, reg)
1743       && SCALAR_INT_MODE_P (reg_mode) != SCALAR_INT_MODE_P (mode))
1744     {
1745       SUBREG_REG (operand) = force_const_mem (reg_mode, reg);
1746       alter_subreg (curr_id->operand_loc[nop], false);
1747       return true;
1748     }
1749   /* Force a reload of the SUBREG_REG if this is a constant or PLUS or
1750      if there may be a problem accessing OPERAND in the outer
1751      mode.  */
1752   if ((REG_P (reg)
1753        && REGNO (reg) >= FIRST_PSEUDO_REGISTER
1754        && (hard_regno = lra_get_regno_hard_regno (REGNO (reg))) >= 0
1755        /* Don't reload paradoxical subregs because we could be looping
1756 	  having repeatedly final regno out of hard regs range.  */
1757        && (hard_regno_nregs (hard_regno, innermode)
1758 	   >= hard_regno_nregs (hard_regno, mode))
1759        && simplify_subreg_regno (hard_regno, innermode,
1760 				 SUBREG_BYTE (operand), mode) < 0
1761        /* Don't reload subreg for matching reload.  It is actually
1762 	  valid subreg in LRA.  */
1763        && ! LRA_SUBREG_P (operand))
1764       || CONSTANT_P (reg) || GET_CODE (reg) == PLUS || MEM_P (reg))
1765     {
1766       enum reg_class rclass;
1767 
1768       if (REG_P (reg))
1769 	/* There is a big probability that we will get the same class
1770 	   for the new pseudo and we will get the same insn which
1771 	   means infinite looping.  So spill the new pseudo.  */
1772 	rclass = NO_REGS;
1773       else
1774 	/* The class will be defined later in curr_insn_transform.  */
1775 	rclass
1776 	  = (enum reg_class) targetm.preferred_reload_class (reg, ALL_REGS);
1777 
1778       if (get_reload_reg (curr_static_id->operand[nop].type, reg_mode, reg,
1779 			  rclass, TRUE, "subreg reg", &new_reg))
1780 	{
1781 	  bool insert_before, insert_after;
1782 	  bitmap_set_bit (&lra_subreg_reload_pseudos, REGNO (new_reg));
1783 
1784 	  insert_before = (type != OP_OUT
1785 			   || read_modify_subreg_p (operand));
1786 	  insert_after = (type != OP_IN);
1787 	  insert_move_for_subreg (insert_before ? &before : NULL,
1788 				  insert_after ? &after : NULL,
1789 				  reg, new_reg);
1790 	}
1791       SUBREG_REG (operand) = new_reg;
1792       lra_process_new_insns (curr_insn, before, after,
1793 			     "Inserting subreg reload");
1794       return true;
1795     }
1796   /* Force a reload for a paradoxical subreg. For paradoxical subreg,
1797      IRA allocates hardreg to the inner pseudo reg according to its mode
1798      instead of the outermode, so the size of the hardreg may not be enough
1799      to contain the outermode operand, in that case we may need to insert
1800      reload for the reg. For the following two types of paradoxical subreg,
1801      we need to insert reload:
1802      1. If the op_type is OP_IN, and the hardreg could not be paired with
1803         other hardreg to contain the outermode operand
1804         (checked by in_hard_reg_set_p), we need to insert the reload.
1805      2. If the op_type is OP_OUT or OP_INOUT.
1806 
1807      Here is a paradoxical subreg example showing how the reload is generated:
1808 
1809      (insn 5 4 7 2 (set (reg:TI 106 [ __comp ])
1810         (subreg:TI (reg:DI 107 [ __comp ]) 0)) {*movti_internal_rex64}
1811 
1812      In IRA, reg107 is allocated to a DImode hardreg. We use x86-64 as example
1813      here, if reg107 is assigned to hardreg R15, because R15 is the last
1814      hardreg, compiler cannot find another hardreg to pair with R15 to
1815      contain TImode data. So we insert a TImode reload reg180 for it.
1816      After reload is inserted:
1817 
1818      (insn 283 0 0 (set (subreg:DI (reg:TI 180 [orig:107 __comp ] [107]) 0)
1819         (reg:DI 107 [ __comp ])) -1
1820      (insn 5 4 7 2 (set (reg:TI 106 [ __comp ])
1821         (subreg:TI (reg:TI 180 [orig:107 __comp ] [107]) 0)) {*movti_internal_rex64}
1822 
1823      Two reload hard registers will be allocated to reg180 to save TImode data
1824      in LRA_assign.
1825 
1826      For LRA pseudos this should normally be handled by the biggest_mode
1827      mechanism.  However, it's possible for new uses of an LRA pseudo
1828      to be introduced after we've allocated it, such as when undoing
1829      inheritance, and the allocated register might not then be appropriate
1830      for the new uses.  */
1831   else if (REG_P (reg)
1832 	   && REGNO (reg) >= FIRST_PSEUDO_REGISTER
1833 	   && paradoxical_subreg_p (operand)
1834 	   && (inner_hard_regno = lra_get_regno_hard_regno (REGNO (reg))) >= 0
1835 	   && ((hard_regno
1836 		= simplify_subreg_regno (inner_hard_regno, innermode,
1837 					 SUBREG_BYTE (operand), mode)) < 0
1838 	       || ((hard_regno_nregs (inner_hard_regno, innermode)
1839 		    < hard_regno_nregs (hard_regno, mode))
1840 		   && (regclass = lra_get_allocno_class (REGNO (reg)))
1841 		   && (type != OP_IN
1842 		       || !in_hard_reg_set_p (reg_class_contents[regclass],
1843 					      mode, hard_regno)
1844 		       || overlaps_hard_reg_set_p (lra_no_alloc_regs,
1845 						   mode, hard_regno)))))
1846     {
1847       /* The class will be defined later in curr_insn_transform.  */
1848       enum reg_class rclass
1849 	= (enum reg_class) targetm.preferred_reload_class (reg, ALL_REGS);
1850 
1851       if (get_reload_reg (curr_static_id->operand[nop].type, mode, reg,
1852                           rclass, TRUE, "paradoxical subreg", &new_reg))
1853         {
1854 	  rtx subreg;
1855 	  bool insert_before, insert_after;
1856 
1857 	  PUT_MODE (new_reg, mode);
1858           subreg = gen_lowpart_SUBREG (innermode, new_reg);
1859 	  bitmap_set_bit (&lra_subreg_reload_pseudos, REGNO (new_reg));
1860 
1861 	  insert_before = (type != OP_OUT);
1862 	  insert_after = (type != OP_IN);
1863 	  insert_move_for_subreg (insert_before ? &before : NULL,
1864 				  insert_after ? &after : NULL,
1865 				  reg, subreg);
1866 	}
1867       SUBREG_REG (operand) = new_reg;
1868       lra_process_new_insns (curr_insn, before, after,
1869                              "Inserting paradoxical subreg reload");
1870       return true;
1871     }
1872   return false;
1873 }
1874 
1875 /* Return TRUE if X refers for a hard register from SET.  */
1876 static bool
uses_hard_regs_p(rtx x,HARD_REG_SET set)1877 uses_hard_regs_p (rtx x, HARD_REG_SET set)
1878 {
1879   int i, j, x_hard_regno;
1880   machine_mode mode;
1881   const char *fmt;
1882   enum rtx_code code;
1883 
1884   if (x == NULL_RTX)
1885     return false;
1886   code = GET_CODE (x);
1887   mode = GET_MODE (x);
1888 
1889   if (code == SUBREG)
1890     {
1891       /* For all SUBREGs we want to check whether the full multi-register
1892 	 overlaps the set.  For normal SUBREGs this means 'get_hard_regno' of
1893 	 the inner register, for paradoxical SUBREGs this means the
1894 	 'get_hard_regno' of the full SUBREG and for complete SUBREGs either is
1895 	 fine.  Use the wider mode for all cases.  */
1896       rtx subreg = SUBREG_REG (x);
1897       mode = wider_subreg_mode (x);
1898       if (mode == GET_MODE (subreg))
1899 	{
1900 	  x = subreg;
1901 	  code = GET_CODE (x);
1902 	}
1903     }
1904 
1905   if (REG_P (x) || SUBREG_P (x))
1906     {
1907       x_hard_regno = get_hard_regno (x, true);
1908       return (x_hard_regno >= 0
1909 	      && overlaps_hard_reg_set_p (set, mode, x_hard_regno));
1910     }
1911   fmt = GET_RTX_FORMAT (code);
1912   for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1913     {
1914       if (fmt[i] == 'e')
1915 	{
1916 	  if (uses_hard_regs_p (XEXP (x, i), set))
1917 	    return true;
1918 	}
1919       else if (fmt[i] == 'E')
1920 	{
1921 	  for (j = XVECLEN (x, i) - 1; j >= 0; j--)
1922 	    if (uses_hard_regs_p (XVECEXP (x, i, j), set))
1923 	      return true;
1924 	}
1925     }
1926   return false;
1927 }
1928 
1929 /* Return true if OP is a spilled pseudo. */
1930 static inline bool
spilled_pseudo_p(rtx op)1931 spilled_pseudo_p (rtx op)
1932 {
1933   return (REG_P (op)
1934 	  && REGNO (op) >= FIRST_PSEUDO_REGISTER && in_mem_p (REGNO (op)));
1935 }
1936 
1937 /* Return true if X is a general constant.  */
1938 static inline bool
general_constant_p(rtx x)1939 general_constant_p (rtx x)
1940 {
1941   return CONSTANT_P (x) && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (x));
1942 }
1943 
1944 static bool
reg_in_class_p(rtx reg,enum reg_class cl)1945 reg_in_class_p (rtx reg, enum reg_class cl)
1946 {
1947   if (cl == NO_REGS)
1948     return get_reg_class (REGNO (reg)) == NO_REGS;
1949   return in_class_p (reg, cl, NULL);
1950 }
1951 
1952 /* Return true if SET of RCLASS contains no hard regs which can be
1953    used in MODE.  */
1954 static bool
prohibited_class_reg_set_mode_p(enum reg_class rclass,HARD_REG_SET & set,machine_mode mode)1955 prohibited_class_reg_set_mode_p (enum reg_class rclass,
1956 				 HARD_REG_SET &set,
1957 				 machine_mode mode)
1958 {
1959   HARD_REG_SET temp;
1960 
1961   lra_assert (hard_reg_set_subset_p (reg_class_contents[rclass], set));
1962   temp = set & ~lra_no_alloc_regs;
1963   return (hard_reg_set_subset_p
1964 	  (temp, ira_prohibited_class_mode_regs[rclass][mode]));
1965 }
1966 
1967 
1968 /* Used to check validity info about small class input operands.  It
1969    should be incremented at start of processing an insn
1970    alternative.  */
1971 static unsigned int curr_small_class_check = 0;
1972 
1973 /* Update number of used inputs of class OP_CLASS for operand NOP
1974    of alternative NALT.  Return true if we have more such class operands
1975    than the number of available regs.  */
1976 static bool
update_and_check_small_class_inputs(int nop,int nalt,enum reg_class op_class)1977 update_and_check_small_class_inputs (int nop, int nalt,
1978 				     enum reg_class op_class)
1979 {
1980   static unsigned int small_class_check[LIM_REG_CLASSES];
1981   static int small_class_input_nums[LIM_REG_CLASSES];
1982 
1983   if (SMALL_REGISTER_CLASS_P (op_class)
1984       /* We are interesting in classes became small because of fixing
1985 	 some hard regs, e.g. by an user through GCC options.  */
1986       && hard_reg_set_intersect_p (reg_class_contents[op_class],
1987 				   ira_no_alloc_regs)
1988       && (curr_static_id->operand[nop].type != OP_OUT
1989 	  || TEST_BIT (curr_static_id->operand[nop].early_clobber_alts, nalt)))
1990     {
1991       if (small_class_check[op_class] == curr_small_class_check)
1992 	small_class_input_nums[op_class]++;
1993       else
1994 	{
1995 	  small_class_check[op_class] = curr_small_class_check;
1996 	  small_class_input_nums[op_class] = 1;
1997 	}
1998       if (small_class_input_nums[op_class] > ira_class_hard_regs_num[op_class])
1999 	return true;
2000     }
2001   return false;
2002 }
2003 
2004 /* Major function to choose the current insn alternative and what
2005    operands should be reloaded and how.	 If ONLY_ALTERNATIVE is not
2006    negative we should consider only this alternative.  Return false if
2007    we cannot choose the alternative or find how to reload the
2008    operands.  */
2009 static bool
process_alt_operands(int only_alternative)2010 process_alt_operands (int only_alternative)
2011 {
2012   bool ok_p = false;
2013   int nop, overall, nalt;
2014   int n_alternatives = curr_static_id->n_alternatives;
2015   int n_operands = curr_static_id->n_operands;
2016   /* LOSERS counts the operands that don't fit this alternative and
2017      would require loading.  */
2018   int losers;
2019   int addr_losers;
2020   /* REJECT is a count of how undesirable this alternative says it is
2021      if any reloading is required.  If the alternative matches exactly
2022      then REJECT is ignored, but otherwise it gets this much counted
2023      against it in addition to the reloading needed.  */
2024   int reject;
2025   /* This is defined by '!' or '?' alternative constraint and added to
2026      reject.  But in some cases it can be ignored.  */
2027   int static_reject;
2028   int op_reject;
2029   /* The number of elements in the following array.  */
2030   int early_clobbered_regs_num;
2031   /* Numbers of operands which are early clobber registers.  */
2032   int early_clobbered_nops[MAX_RECOG_OPERANDS];
2033   enum reg_class curr_alt[MAX_RECOG_OPERANDS];
2034   HARD_REG_SET curr_alt_set[MAX_RECOG_OPERANDS];
2035   bool curr_alt_match_win[MAX_RECOG_OPERANDS];
2036   bool curr_alt_win[MAX_RECOG_OPERANDS];
2037   bool curr_alt_offmemok[MAX_RECOG_OPERANDS];
2038   int curr_alt_matches[MAX_RECOG_OPERANDS];
2039   /* The number of elements in the following array.  */
2040   int curr_alt_dont_inherit_ops_num;
2041   /* Numbers of operands whose reload pseudos should not be inherited.	*/
2042   int curr_alt_dont_inherit_ops[MAX_RECOG_OPERANDS];
2043   rtx op;
2044   /* The register when the operand is a subreg of register, otherwise the
2045      operand itself.  */
2046   rtx no_subreg_reg_operand[MAX_RECOG_OPERANDS];
2047   /* The register if the operand is a register or subreg of register,
2048      otherwise NULL.  */
2049   rtx operand_reg[MAX_RECOG_OPERANDS];
2050   int hard_regno[MAX_RECOG_OPERANDS];
2051   machine_mode biggest_mode[MAX_RECOG_OPERANDS];
2052   int reload_nregs, reload_sum;
2053   bool costly_p;
2054   enum reg_class cl;
2055 
2056   /* Calculate some data common for all alternatives to speed up the
2057      function.	*/
2058   for (nop = 0; nop < n_operands; nop++)
2059     {
2060       rtx reg;
2061 
2062       op = no_subreg_reg_operand[nop] = *curr_id->operand_loc[nop];
2063       /* The real hard regno of the operand after the allocation.  */
2064       hard_regno[nop] = get_hard_regno (op, true);
2065 
2066       operand_reg[nop] = reg = op;
2067       biggest_mode[nop] = GET_MODE (op);
2068       if (GET_CODE (op) == SUBREG)
2069 	{
2070 	  biggest_mode[nop] = wider_subreg_mode (op);
2071 	  operand_reg[nop] = reg = SUBREG_REG (op);
2072 	}
2073       if (! REG_P (reg))
2074 	operand_reg[nop] = NULL_RTX;
2075       else if (REGNO (reg) >= FIRST_PSEUDO_REGISTER
2076 	       || ((int) REGNO (reg)
2077 		   == lra_get_elimination_hard_regno (REGNO (reg))))
2078 	no_subreg_reg_operand[nop] = reg;
2079       else
2080 	operand_reg[nop] = no_subreg_reg_operand[nop]
2081 	  /* Just use natural mode for elimination result.  It should
2082 	     be enough for extra constraints hooks.  */
2083 	  = regno_reg_rtx[hard_regno[nop]];
2084     }
2085 
2086   /* The constraints are made of several alternatives.	Each operand's
2087      constraint looks like foo,bar,... with commas separating the
2088      alternatives.  The first alternatives for all operands go
2089      together, the second alternatives go together, etc.
2090 
2091      First loop over alternatives.  */
2092   alternative_mask preferred = curr_id->preferred_alternatives;
2093   if (only_alternative >= 0)
2094     preferred &= ALTERNATIVE_BIT (only_alternative);
2095 
2096   for (nalt = 0; nalt < n_alternatives; nalt++)
2097     {
2098       /* Loop over operands for one constraint alternative.  */
2099       if (!TEST_BIT (preferred, nalt))
2100 	continue;
2101 
2102       bool matching_early_clobber[MAX_RECOG_OPERANDS];
2103       curr_small_class_check++;
2104       overall = losers = addr_losers = 0;
2105       static_reject = reject = reload_nregs = reload_sum = 0;
2106       for (nop = 0; nop < n_operands; nop++)
2107 	{
2108 	  int inc = (curr_static_id
2109 		     ->operand_alternative[nalt * n_operands + nop].reject);
2110 	  if (lra_dump_file != NULL && inc != 0)
2111 	    fprintf (lra_dump_file,
2112 		     "            Staticly defined alt reject+=%d\n", inc);
2113 	  static_reject += inc;
2114 	  matching_early_clobber[nop] = 0;
2115 	}
2116       reject += static_reject;
2117       early_clobbered_regs_num = 0;
2118 
2119       for (nop = 0; nop < n_operands; nop++)
2120 	{
2121 	  const char *p;
2122 	  char *end;
2123 	  int len, c, m, i, opalt_num, this_alternative_matches;
2124 	  bool win, did_match, offmemok, early_clobber_p;
2125 	  /* false => this operand can be reloaded somehow for this
2126 	     alternative.  */
2127 	  bool badop;
2128 	  /* true => this operand can be reloaded if the alternative
2129 	     allows regs.  */
2130 	  bool winreg;
2131 	  /* True if a constant forced into memory would be OK for
2132 	     this operand.  */
2133 	  bool constmemok;
2134 	  enum reg_class this_alternative, this_costly_alternative;
2135 	  HARD_REG_SET this_alternative_set, this_costly_alternative_set;
2136 	  bool this_alternative_match_win, this_alternative_win;
2137 	  bool this_alternative_offmemok;
2138 	  bool scratch_p;
2139 	  machine_mode mode;
2140 	  enum constraint_num cn;
2141 
2142 	  opalt_num = nalt * n_operands + nop;
2143 	  if (curr_static_id->operand_alternative[opalt_num].anything_ok)
2144 	    {
2145 	      /* Fast track for no constraints at all.	*/
2146 	      curr_alt[nop] = NO_REGS;
2147 	      CLEAR_HARD_REG_SET (curr_alt_set[nop]);
2148 	      curr_alt_win[nop] = true;
2149 	      curr_alt_match_win[nop] = false;
2150 	      curr_alt_offmemok[nop] = false;
2151 	      curr_alt_matches[nop] = -1;
2152 	      continue;
2153 	    }
2154 
2155 	  op = no_subreg_reg_operand[nop];
2156 	  mode = curr_operand_mode[nop];
2157 
2158 	  win = did_match = winreg = offmemok = constmemok = false;
2159 	  badop = true;
2160 
2161 	  early_clobber_p = false;
2162 	  p = curr_static_id->operand_alternative[opalt_num].constraint;
2163 
2164 	  this_costly_alternative = this_alternative = NO_REGS;
2165 	  /* We update set of possible hard regs besides its class
2166 	     because reg class might be inaccurate.  For example,
2167 	     union of LO_REGS (l), HI_REGS(h), and STACK_REG(k) in ARM
2168 	     is translated in HI_REGS because classes are merged by
2169 	     pairs and there is no accurate intermediate class.	 */
2170 	  CLEAR_HARD_REG_SET (this_alternative_set);
2171 	  CLEAR_HARD_REG_SET (this_costly_alternative_set);
2172 	  this_alternative_win = false;
2173 	  this_alternative_match_win = false;
2174 	  this_alternative_offmemok = false;
2175 	  this_alternative_matches = -1;
2176 
2177 	  /* An empty constraint should be excluded by the fast
2178 	     track.  */
2179 	  lra_assert (*p != 0 && *p != ',');
2180 
2181 	  op_reject = 0;
2182 	  /* Scan this alternative's specs for this operand; set WIN
2183 	     if the operand fits any letter in this alternative.
2184 	     Otherwise, clear BADOP if this operand could fit some
2185 	     letter after reloads, or set WINREG if this operand could
2186 	     fit after reloads provided the constraint allows some
2187 	     registers.	 */
2188 	  costly_p = false;
2189 	  do
2190 	    {
2191 	      switch ((c = *p, len = CONSTRAINT_LEN (c, p)), c)
2192 		{
2193 		case '\0':
2194 		  len = 0;
2195 		  break;
2196 		case ',':
2197 		  c = '\0';
2198 		  break;
2199 
2200 		case '&':
2201 		  early_clobber_p = true;
2202 		  break;
2203 
2204 		case '$':
2205 		  op_reject += LRA_MAX_REJECT;
2206 		  break;
2207 		case '^':
2208 		  op_reject += LRA_LOSER_COST_FACTOR;
2209 		  break;
2210 
2211 		case '#':
2212 		  /* Ignore rest of this alternative.  */
2213 		  c = '\0';
2214 		  break;
2215 
2216 		case '0':  case '1':  case '2':	 case '3':  case '4':
2217 		case '5':  case '6':  case '7':	 case '8':  case '9':
2218 		  {
2219 		    int m_hregno;
2220 		    bool match_p;
2221 
2222 		    m = strtoul (p, &end, 10);
2223 		    p = end;
2224 		    len = 0;
2225 		    lra_assert (nop > m);
2226 
2227 		    /* Reject matches if we don't know which operand is
2228 		       bigger.  This situation would arguably be a bug in
2229 		       an .md pattern, but could also occur in a user asm.  */
2230 		    if (!ordered_p (GET_MODE_SIZE (biggest_mode[m]),
2231 				    GET_MODE_SIZE (biggest_mode[nop])))
2232 		      break;
2233 
2234 		    /* Don't match wrong asm insn operands for proper
2235 		       diagnostic later.  */
2236 		    if (INSN_CODE (curr_insn) < 0
2237 			&& (curr_operand_mode[m] == BLKmode
2238 			    || curr_operand_mode[nop] == BLKmode)
2239 			&& curr_operand_mode[m] != curr_operand_mode[nop])
2240 		      break;
2241 
2242 		    m_hregno = get_hard_regno (*curr_id->operand_loc[m], false);
2243 		    /* We are supposed to match a previous operand.
2244 		       If we do, we win if that one did.  If we do
2245 		       not, count both of the operands as losers.
2246 		       (This is too conservative, since most of the
2247 		       time only a single reload insn will be needed
2248 		       to make the two operands win.  As a result,
2249 		       this alternative may be rejected when it is
2250 		       actually desirable.)  */
2251 		    match_p = false;
2252 		    if (operands_match_p (*curr_id->operand_loc[nop],
2253 					  *curr_id->operand_loc[m], m_hregno))
2254 		      {
2255 			/* We should reject matching of an early
2256 			   clobber operand if the matching operand is
2257 			   not dying in the insn.  */
2258 			if (!TEST_BIT (curr_static_id->operand[m]
2259 				       .early_clobber_alts, nalt)
2260 			    || operand_reg[nop] == NULL_RTX
2261 			    || (find_regno_note (curr_insn, REG_DEAD,
2262 						 REGNO (op))
2263 				|| REGNO (op) == REGNO (operand_reg[m])))
2264 			  match_p = true;
2265 		      }
2266 		    if (match_p)
2267 		      {
2268 			/* If we are matching a non-offsettable
2269 			   address where an offsettable address was
2270 			   expected, then we must reject this
2271 			   combination, because we can't reload
2272 			   it.	*/
2273 			if (curr_alt_offmemok[m]
2274 			    && MEM_P (*curr_id->operand_loc[m])
2275 			    && curr_alt[m] == NO_REGS && ! curr_alt_win[m])
2276 			  continue;
2277 		      }
2278 		    else
2279 		      {
2280 			/* If the operands do not match and one
2281 			   operand is INOUT, we can not match them.
2282 			   Try other possibilities, e.g. other
2283 			   alternatives or commutative operand
2284 			   exchange.  */
2285 			if (curr_static_id->operand[nop].type == OP_INOUT
2286 			    || curr_static_id->operand[m].type == OP_INOUT)
2287 			  break;
2288 			/* Operands don't match.  If the operands are
2289 			   different user defined explicit hard
2290 			   registers, then we cannot make them match
2291 			   when one is early clobber operand.  */
2292 			if ((REG_P (*curr_id->operand_loc[nop])
2293 			     || SUBREG_P (*curr_id->operand_loc[nop]))
2294 			    && (REG_P (*curr_id->operand_loc[m])
2295 				|| SUBREG_P (*curr_id->operand_loc[m])))
2296 			  {
2297 			    rtx nop_reg = *curr_id->operand_loc[nop];
2298 			    if (SUBREG_P (nop_reg))
2299 			      nop_reg = SUBREG_REG (nop_reg);
2300 			    rtx m_reg = *curr_id->operand_loc[m];
2301 			    if (SUBREG_P (m_reg))
2302 			      m_reg = SUBREG_REG (m_reg);
2303 
2304 			    if (REG_P (nop_reg)
2305 				&& HARD_REGISTER_P (nop_reg)
2306 				&& REG_USERVAR_P (nop_reg)
2307 				&& REG_P (m_reg)
2308 				&& HARD_REGISTER_P (m_reg)
2309 				&& REG_USERVAR_P (m_reg))
2310 			      {
2311 				int i;
2312 
2313 				for (i = 0; i < early_clobbered_regs_num; i++)
2314 				  if (m == early_clobbered_nops[i])
2315 				    break;
2316 				if (i < early_clobbered_regs_num
2317 				    || early_clobber_p)
2318 				  break;
2319 			      }
2320 			  }
2321 			/* Both operands must allow a reload register,
2322 			   otherwise we cannot make them match.  */
2323 			if (curr_alt[m] == NO_REGS)
2324 			  break;
2325 			/* Retroactively mark the operand we had to
2326 			   match as a loser, if it wasn't already and
2327 			   it wasn't matched to a register constraint
2328 			   (e.g it might be matched by memory). */
2329 			if (curr_alt_win[m]
2330 			    && (operand_reg[m] == NULL_RTX
2331 				|| hard_regno[m] < 0))
2332 			  {
2333 			    losers++;
2334 			    reload_nregs
2335 			      += (ira_reg_class_max_nregs[curr_alt[m]]
2336 				  [GET_MODE (*curr_id->operand_loc[m])]);
2337 			  }
2338 
2339 			/* Prefer matching earlyclobber alternative as
2340 			   it results in less hard regs required for
2341 			   the insn than a non-matching earlyclobber
2342 			   alternative.  */
2343 			if (TEST_BIT (curr_static_id->operand[m]
2344 				      .early_clobber_alts, nalt))
2345 			  {
2346 			    if (lra_dump_file != NULL)
2347 			      fprintf
2348 				(lra_dump_file,
2349 				 "            %d Matching earlyclobber alt:"
2350 				 " reject--\n",
2351 				 nop);
2352 			    if (!matching_early_clobber[m])
2353 			      {
2354 				reject--;
2355 				matching_early_clobber[m] = 1;
2356 			      }
2357 			  }
2358 			/* Otherwise we prefer no matching
2359 			   alternatives because it gives more freedom
2360 			   in RA.  */
2361 			else if (operand_reg[nop] == NULL_RTX
2362 				 || (find_regno_note (curr_insn, REG_DEAD,
2363 						      REGNO (operand_reg[nop]))
2364 				     == NULL_RTX))
2365 			  {
2366 			    if (lra_dump_file != NULL)
2367 			      fprintf
2368 				(lra_dump_file,
2369 				 "            %d Matching alt: reject+=2\n",
2370 				 nop);
2371 			    reject += 2;
2372 			  }
2373 		      }
2374 		    /* If we have to reload this operand and some
2375 		       previous operand also had to match the same
2376 		       thing as this operand, we don't know how to do
2377 		       that.  */
2378 		    if (!match_p || !curr_alt_win[m])
2379 		      {
2380 			for (i = 0; i < nop; i++)
2381 			  if (curr_alt_matches[i] == m)
2382 			    break;
2383 			if (i < nop)
2384 			  break;
2385 		      }
2386 		    else
2387 		      did_match = true;
2388 
2389 		    this_alternative_matches = m;
2390 		    /* This can be fixed with reloads if the operand
2391 		       we are supposed to match can be fixed with
2392 		       reloads. */
2393 		    badop = false;
2394 		    this_alternative = curr_alt[m];
2395 		    this_alternative_set = curr_alt_set[m];
2396 		    winreg = this_alternative != NO_REGS;
2397 		    break;
2398 		  }
2399 
2400 		case 'g':
2401 		  if (MEM_P (op)
2402 		      || general_constant_p (op)
2403 		      || spilled_pseudo_p (op))
2404 		    win = true;
2405 		  cl = GENERAL_REGS;
2406 		  goto reg;
2407 
2408 		default:
2409 		  cn = lookup_constraint (p);
2410 		  switch (get_constraint_type (cn))
2411 		    {
2412 		    case CT_REGISTER:
2413 		      cl = reg_class_for_constraint (cn);
2414 		      if (cl != NO_REGS)
2415 			goto reg;
2416 		      break;
2417 
2418 		    case CT_CONST_INT:
2419 		      if (CONST_INT_P (op)
2420 			  && insn_const_int_ok_for_constraint (INTVAL (op), cn))
2421 			win = true;
2422 		      break;
2423 
2424 		    case CT_MEMORY:
2425 		    case CT_RELAXED_MEMORY:
2426 		      if (MEM_P (op)
2427 			  && satisfies_memory_constraint_p (op, cn))
2428 			win = true;
2429 		      else if (spilled_pseudo_p (op))
2430 			win = true;
2431 
2432 		      /* If we didn't already win, we can reload constants
2433 			 via force_const_mem or put the pseudo value into
2434 			 memory, or make other memory by reloading the
2435 			 address like for 'o'.  */
2436 		      if (CONST_POOL_OK_P (mode, op)
2437 			  || MEM_P (op) || REG_P (op)
2438 			  /* We can restore the equiv insn by a
2439 			     reload.  */
2440 			  || equiv_substition_p[nop])
2441 			badop = false;
2442 		      constmemok = true;
2443 		      offmemok = true;
2444 		      break;
2445 
2446 		    case CT_ADDRESS:
2447 		      /* An asm operand with an address constraint
2448 			 that doesn't satisfy address_operand has
2449 			 is_address cleared, so that we don't try to
2450 			 make a non-address fit.  */
2451 		      if (!curr_static_id->operand[nop].is_address)
2452 			break;
2453 		      /* If we didn't already win, we can reload the address
2454 			 into a base register.  */
2455 		      if (satisfies_address_constraint_p (op, cn))
2456 			win = true;
2457 		      cl = base_reg_class (VOIDmode, ADDR_SPACE_GENERIC,
2458 					   ADDRESS, SCRATCH);
2459 		      badop = false;
2460 		      goto reg;
2461 
2462 		    case CT_FIXED_FORM:
2463 		      if (constraint_satisfied_p (op, cn))
2464 			win = true;
2465 		      break;
2466 
2467 		    case CT_SPECIAL_MEMORY:
2468 		      if (satisfies_memory_constraint_p (op, cn))
2469 			win = true;
2470 		      else if (spilled_pseudo_p (op))
2471 			win = true;
2472 		      break;
2473 		    }
2474 		  break;
2475 
2476 		reg:
2477 		  if (mode == BLKmode)
2478 		    break;
2479 		  this_alternative = reg_class_subunion[this_alternative][cl];
2480 		  this_alternative_set |= reg_class_contents[cl];
2481 		  if (costly_p)
2482 		    {
2483 		      this_costly_alternative
2484 			= reg_class_subunion[this_costly_alternative][cl];
2485 		      this_costly_alternative_set |= reg_class_contents[cl];
2486 		    }
2487 		  winreg = true;
2488 		  if (REG_P (op))
2489 		    {
2490 		      if (hard_regno[nop] >= 0
2491 			  && in_hard_reg_set_p (this_alternative_set,
2492 						mode, hard_regno[nop]))
2493 			win = true;
2494 		      else if (hard_regno[nop] < 0
2495 			       && in_class_p (op, this_alternative, NULL))
2496 			win = true;
2497 		    }
2498 		  break;
2499 		}
2500 	      if (c != ' ' && c != '\t')
2501 		costly_p = c == '*';
2502 	    }
2503 	  while ((p += len), c);
2504 
2505 	  scratch_p = (operand_reg[nop] != NULL_RTX
2506 		       && ira_former_scratch_p (REGNO (operand_reg[nop])));
2507 	  /* Record which operands fit this alternative.  */
2508 	  if (win)
2509 	    {
2510 	      this_alternative_win = true;
2511 	      if (operand_reg[nop] != NULL_RTX)
2512 		{
2513 		  if (hard_regno[nop] >= 0)
2514 		    {
2515 		      if (in_hard_reg_set_p (this_costly_alternative_set,
2516 					     mode, hard_regno[nop]))
2517 			{
2518 			  if (lra_dump_file != NULL)
2519 			    fprintf (lra_dump_file,
2520 				     "            %d Costly set: reject++\n",
2521 				     nop);
2522 			  reject++;
2523 			}
2524 		    }
2525 		  else
2526 		    {
2527 		      /* Prefer won reg to spilled pseudo under other
2528 			 equal conditions for possibe inheritance.  */
2529 		      if (! scratch_p)
2530 			{
2531 			  if (lra_dump_file != NULL)
2532 			    fprintf
2533 			      (lra_dump_file,
2534 			       "            %d Non pseudo reload: reject++\n",
2535 			       nop);
2536 			  reject++;
2537 			}
2538 		      if (in_class_p (operand_reg[nop],
2539 				      this_costly_alternative, NULL))
2540 			{
2541 			  if (lra_dump_file != NULL)
2542 			    fprintf
2543 			      (lra_dump_file,
2544 			       "            %d Non pseudo costly reload:"
2545 			       " reject++\n",
2546 			       nop);
2547 			  reject++;
2548 			}
2549 		    }
2550 		  /* We simulate the behavior of old reload here.
2551 		     Although scratches need hard registers and it
2552 		     might result in spilling other pseudos, no reload
2553 		     insns are generated for the scratches.  So it
2554 		     might cost something but probably less than old
2555 		     reload pass believes.  */
2556 		  if (scratch_p)
2557 		    {
2558 		      if (lra_dump_file != NULL)
2559 			fprintf (lra_dump_file,
2560 				 "            %d Scratch win: reject+=2\n",
2561 				 nop);
2562 		      reject += 2;
2563 		    }
2564 		}
2565 	    }
2566 	  else if (did_match)
2567 	    this_alternative_match_win = true;
2568 	  else
2569 	    {
2570 	      int const_to_mem = 0;
2571 	      bool no_regs_p;
2572 
2573 	      reject += op_reject;
2574 	      /* Never do output reload of stack pointer.  It makes
2575 		 impossible to do elimination when SP is changed in
2576 		 RTL.  */
2577 	      if (op == stack_pointer_rtx && ! frame_pointer_needed
2578 		  && curr_static_id->operand[nop].type != OP_IN)
2579 		goto fail;
2580 
2581 	      /* If this alternative asks for a specific reg class, see if there
2582 		 is at least one allocatable register in that class.  */
2583 	      no_regs_p
2584 		= (this_alternative == NO_REGS
2585 		   || (hard_reg_set_subset_p
2586 		       (reg_class_contents[this_alternative],
2587 			lra_no_alloc_regs)));
2588 
2589 	      /* For asms, verify that the class for this alternative is possible
2590 		 for the mode that is specified.  */
2591 	      if (!no_regs_p && INSN_CODE (curr_insn) < 0)
2592 		{
2593 		  int i;
2594 		  for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
2595 		    if (targetm.hard_regno_mode_ok (i, mode)
2596 			&& in_hard_reg_set_p (reg_class_contents[this_alternative],
2597 					      mode, i))
2598 		      break;
2599 		  if (i == FIRST_PSEUDO_REGISTER)
2600 		    winreg = false;
2601 		}
2602 
2603 	      /* If this operand accepts a register, and if the
2604 		 register class has at least one allocatable register,
2605 		 then this operand can be reloaded.  */
2606 	      if (winreg && !no_regs_p)
2607 		badop = false;
2608 
2609 	      if (badop)
2610 		{
2611 		  if (lra_dump_file != NULL)
2612 		    fprintf (lra_dump_file,
2613 			     "            alt=%d: Bad operand -- refuse\n",
2614 			     nalt);
2615 		  goto fail;
2616 		}
2617 
2618 	      if (this_alternative != NO_REGS)
2619 		{
2620 		  HARD_REG_SET available_regs
2621 		    = (reg_class_contents[this_alternative]
2622 		       & ~((ira_prohibited_class_mode_regs
2623 			    [this_alternative][mode])
2624 			   | lra_no_alloc_regs));
2625 		  if (hard_reg_set_empty_p (available_regs))
2626 		    {
2627 		      /* There are no hard regs holding a value of given
2628 			 mode.  */
2629 		      if (offmemok)
2630 			{
2631 			  this_alternative = NO_REGS;
2632 			  if (lra_dump_file != NULL)
2633 			    fprintf (lra_dump_file,
2634 				     "            %d Using memory because of"
2635 				     " a bad mode: reject+=2\n",
2636 				     nop);
2637 			  reject += 2;
2638 			}
2639 		      else
2640 			{
2641 			  if (lra_dump_file != NULL)
2642 			    fprintf (lra_dump_file,
2643 				     "            alt=%d: Wrong mode -- refuse\n",
2644 				     nalt);
2645 			  goto fail;
2646 			}
2647 		    }
2648 		}
2649 
2650 	      /* If not assigned pseudo has a class which a subset of
2651 		 required reg class, it is a less costly alternative
2652 		 as the pseudo still can get a hard reg of necessary
2653 		 class.  */
2654 	      if (! no_regs_p && REG_P (op) && hard_regno[nop] < 0
2655 		  && (cl = get_reg_class (REGNO (op))) != NO_REGS
2656 		  && ira_class_subset_p[this_alternative][cl])
2657 		{
2658 		  if (lra_dump_file != NULL)
2659 		    fprintf
2660 		      (lra_dump_file,
2661 		       "            %d Super set class reg: reject-=3\n", nop);
2662 		  reject -= 3;
2663 		}
2664 
2665 	      this_alternative_offmemok = offmemok;
2666 	      if (this_costly_alternative != NO_REGS)
2667 		{
2668 		  if (lra_dump_file != NULL)
2669 		    fprintf (lra_dump_file,
2670 			     "            %d Costly loser: reject++\n", nop);
2671 		  reject++;
2672 		}
2673 	      /* If the operand is dying, has a matching constraint,
2674 		 and satisfies constraints of the matched operand
2675 		 which failed to satisfy the own constraints, most probably
2676 		 the reload for this operand will be gone.  */
2677 	      if (this_alternative_matches >= 0
2678 		  && !curr_alt_win[this_alternative_matches]
2679 		  && REG_P (op)
2680 		  && find_regno_note (curr_insn, REG_DEAD, REGNO (op))
2681 		  && (hard_regno[nop] >= 0
2682 		      ? in_hard_reg_set_p (this_alternative_set,
2683 					   mode, hard_regno[nop])
2684 		      : in_class_p (op, this_alternative, NULL)))
2685 		{
2686 		  if (lra_dump_file != NULL)
2687 		    fprintf
2688 		      (lra_dump_file,
2689 		       "            %d Dying matched operand reload: reject++\n",
2690 		       nop);
2691 		  reject++;
2692 		}
2693 	      else
2694 		{
2695 		  /* Strict_low_part requires to reload the register
2696 		     not the sub-register.  In this case we should
2697 		     check that a final reload hard reg can hold the
2698 		     value mode.  */
2699 		  if (curr_static_id->operand[nop].strict_low
2700 		      && REG_P (op)
2701 		      && hard_regno[nop] < 0
2702 		      && GET_CODE (*curr_id->operand_loc[nop]) == SUBREG
2703 		      && ira_class_hard_regs_num[this_alternative] > 0
2704 		      && (!targetm.hard_regno_mode_ok
2705 			  (ira_class_hard_regs[this_alternative][0],
2706 			   GET_MODE (*curr_id->operand_loc[nop]))))
2707 		    {
2708 		      if (lra_dump_file != NULL)
2709 			fprintf
2710 			  (lra_dump_file,
2711 			   "            alt=%d: Strict low subreg reload -- refuse\n",
2712 			   nalt);
2713 		      goto fail;
2714 		    }
2715 		  losers++;
2716 		}
2717 	      if (operand_reg[nop] != NULL_RTX
2718 		  /* Output operands and matched input operands are
2719 		     not inherited.  The following conditions do not
2720 		     exactly describe the previous statement but they
2721 		     are pretty close.  */
2722 		  && curr_static_id->operand[nop].type != OP_OUT
2723 		  && (this_alternative_matches < 0
2724 		      || curr_static_id->operand[nop].type != OP_IN))
2725 		{
2726 		  int last_reload = (lra_reg_info[ORIGINAL_REGNO
2727 						  (operand_reg[nop])]
2728 				     .last_reload);
2729 
2730 		  /* The value of reload_sum has sense only if we
2731 		     process insns in their order.  It happens only on
2732 		     the first constraints sub-pass when we do most of
2733 		     reload work.  */
2734 		  if (lra_constraint_iter == 1 && last_reload > bb_reload_num)
2735 		    reload_sum += last_reload - bb_reload_num;
2736 		}
2737 	      /* If this is a constant that is reloaded into the
2738 		 desired class by copying it to memory first, count
2739 		 that as another reload.  This is consistent with
2740 		 other code and is required to avoid choosing another
2741 		 alternative when the constant is moved into memory.
2742 		 Note that the test here is precisely the same as in
2743 		 the code below that calls force_const_mem.  */
2744 	      if (CONST_POOL_OK_P (mode, op)
2745 		  && ((targetm.preferred_reload_class
2746 		       (op, this_alternative) == NO_REGS)
2747 		      || no_input_reloads_p))
2748 		{
2749 		  const_to_mem = 1;
2750 		  if (! no_regs_p)
2751 		    losers++;
2752 		}
2753 
2754 	      /* Alternative loses if it requires a type of reload not
2755 		 permitted for this insn.  We can always reload
2756 		 objects with a REG_UNUSED note.  */
2757 	      if ((curr_static_id->operand[nop].type != OP_IN
2758 		   && no_output_reloads_p
2759 		   && ! find_reg_note (curr_insn, REG_UNUSED, op))
2760 		  || (curr_static_id->operand[nop].type != OP_OUT
2761 		      && no_input_reloads_p && ! const_to_mem)
2762 		  || (this_alternative_matches >= 0
2763 		      && (no_input_reloads_p
2764 			  || (no_output_reloads_p
2765 			      && (curr_static_id->operand
2766 				  [this_alternative_matches].type != OP_IN)
2767 			      && ! find_reg_note (curr_insn, REG_UNUSED,
2768 						  no_subreg_reg_operand
2769 						  [this_alternative_matches])))))
2770 		{
2771 		  if (lra_dump_file != NULL)
2772 		    fprintf
2773 		      (lra_dump_file,
2774 		       "            alt=%d: No input/otput reload -- refuse\n",
2775 		       nalt);
2776 		  goto fail;
2777 		}
2778 
2779 	      /* Alternative loses if it required class pseudo cannot
2780 		 hold value of required mode.  Such insns can be
2781 		 described by insn definitions with mode iterators.  */
2782 	      if (GET_MODE (*curr_id->operand_loc[nop]) != VOIDmode
2783 		  && ! hard_reg_set_empty_p (this_alternative_set)
2784 		  /* It is common practice for constraints to use a
2785 		     class which does not have actually enough regs to
2786 		     hold the value (e.g. x86 AREG for mode requiring
2787 		     more one general reg).  Therefore we have 2
2788 		     conditions to check that the reload pseudo cannot
2789 		     hold the mode value.  */
2790 		  && (!targetm.hard_regno_mode_ok
2791 		      (ira_class_hard_regs[this_alternative][0],
2792 		       GET_MODE (*curr_id->operand_loc[nop])))
2793 		  /* The above condition is not enough as the first
2794 		     reg in ira_class_hard_regs can be not aligned for
2795 		     multi-words mode values.  */
2796 		  && (prohibited_class_reg_set_mode_p
2797 		      (this_alternative, this_alternative_set,
2798 		       GET_MODE (*curr_id->operand_loc[nop]))))
2799 		{
2800 		  if (lra_dump_file != NULL)
2801 		    fprintf (lra_dump_file,
2802 			     "            alt=%d: reload pseudo for op %d "
2803 			     "cannot hold the mode value -- refuse\n",
2804 			     nalt, nop);
2805 		  goto fail;
2806 		}
2807 
2808 	      /* Check strong discouragement of reload of non-constant
2809 		 into class THIS_ALTERNATIVE.  */
2810 	      if (! CONSTANT_P (op) && ! no_regs_p
2811 		  && (targetm.preferred_reload_class
2812 		      (op, this_alternative) == NO_REGS
2813 		      || (curr_static_id->operand[nop].type == OP_OUT
2814 			  && (targetm.preferred_output_reload_class
2815 			      (op, this_alternative) == NO_REGS))))
2816 		{
2817 		  if (offmemok && REG_P (op))
2818 		    {
2819 		      if (lra_dump_file != NULL)
2820 			fprintf
2821 			  (lra_dump_file,
2822 			   "            %d Spill pseudo into memory: reject+=3\n",
2823 			   nop);
2824 		      reject += 3;
2825 		    }
2826 		  else
2827 		    {
2828 		      if (lra_dump_file != NULL)
2829 			fprintf
2830 			  (lra_dump_file,
2831 			   "            %d Non-prefered reload: reject+=%d\n",
2832 			   nop, LRA_MAX_REJECT);
2833 		      reject += LRA_MAX_REJECT;
2834 		    }
2835 		}
2836 
2837 	      if (! (MEM_P (op) && offmemok)
2838 		  && ! (const_to_mem && constmemok))
2839 		{
2840 		  /* We prefer to reload pseudos over reloading other
2841 		     things, since such reloads may be able to be
2842 		     eliminated later.  So bump REJECT in other cases.
2843 		     Don't do this in the case where we are forcing a
2844 		     constant into memory and it will then win since
2845 		     we don't want to have a different alternative
2846 		     match then.  */
2847 		  if (! (REG_P (op) && REGNO (op) >= FIRST_PSEUDO_REGISTER))
2848 		    {
2849 		      if (lra_dump_file != NULL)
2850 			fprintf
2851 			  (lra_dump_file,
2852 			   "            %d Non-pseudo reload: reject+=2\n",
2853 			   nop);
2854 		      reject += 2;
2855 		    }
2856 
2857 		  if (! no_regs_p)
2858 		    reload_nregs
2859 		      += ira_reg_class_max_nregs[this_alternative][mode];
2860 
2861 		  if (SMALL_REGISTER_CLASS_P (this_alternative))
2862 		    {
2863 		      if (lra_dump_file != NULL)
2864 			fprintf
2865 			  (lra_dump_file,
2866 			   "            %d Small class reload: reject+=%d\n",
2867 			   nop, LRA_LOSER_COST_FACTOR / 2);
2868 		      reject += LRA_LOSER_COST_FACTOR / 2;
2869 		    }
2870 		}
2871 
2872 	      /* We are trying to spill pseudo into memory.  It is
2873 		 usually more costly than moving to a hard register
2874 		 although it might takes the same number of
2875 		 reloads.
2876 
2877 		 Non-pseudo spill may happen also.  Suppose a target allows both
2878 		 register and memory in the operand constraint alternatives,
2879 		 then it's typical that an eliminable register has a substition
2880 		 of "base + offset" which can either be reloaded by a simple
2881 		 "new_reg <= base + offset" which will match the register
2882 		 constraint, or a similar reg addition followed by further spill
2883 		 to and reload from memory which will match the memory
2884 		 constraint, but this memory spill will be much more costly
2885 		 usually.
2886 
2887 		 Code below increases the reject for both pseudo and non-pseudo
2888 		 spill.  */
2889 	      if (no_regs_p
2890 		  && !(MEM_P (op) && offmemok)
2891 		  && !(REG_P (op) && hard_regno[nop] < 0))
2892 		{
2893 		  if (lra_dump_file != NULL)
2894 		    fprintf
2895 		      (lra_dump_file,
2896 		       "            %d Spill %spseudo into memory: reject+=3\n",
2897 		       nop, REG_P (op) ? "" : "Non-");
2898 		  reject += 3;
2899 		  if (VECTOR_MODE_P (mode))
2900 		    {
2901 		      /* Spilling vectors into memory is usually more
2902 			 costly as they contain big values.  */
2903 		      if (lra_dump_file != NULL)
2904 			fprintf
2905 			  (lra_dump_file,
2906 			   "            %d Spill vector pseudo: reject+=2\n",
2907 			   nop);
2908 		      reject += 2;
2909 		    }
2910 		}
2911 
2912 	      /* When we use an operand requiring memory in given
2913 		 alternative, the insn should write *and* read the
2914 		 value to/from memory it is costly in comparison with
2915 		 an insn alternative which does not use memory
2916 		 (e.g. register or immediate operand).  We exclude
2917 		 memory operand for such case as we can satisfy the
2918 		 memory constraints by reloading address.  */
2919 	      if (no_regs_p && offmemok && !MEM_P (op))
2920 		{
2921 		  if (lra_dump_file != NULL)
2922 		    fprintf
2923 		      (lra_dump_file,
2924 		       "            Using memory insn operand %d: reject+=3\n",
2925 		       nop);
2926 		  reject += 3;
2927 		}
2928 
2929 	      /* If reload requires moving value through secondary
2930 		 memory, it will need one more insn at least.  */
2931 	      if (this_alternative != NO_REGS
2932 		  && REG_P (op) && (cl = get_reg_class (REGNO (op))) != NO_REGS
2933 		  && ((curr_static_id->operand[nop].type != OP_OUT
2934 		       && targetm.secondary_memory_needed (GET_MODE (op), cl,
2935 							   this_alternative))
2936 		      || (curr_static_id->operand[nop].type != OP_IN
2937 			  && (targetm.secondary_memory_needed
2938 			      (GET_MODE (op), this_alternative, cl)))))
2939 		losers++;
2940 
2941 	      if (MEM_P (op) && offmemok)
2942 		addr_losers++;
2943 	      else
2944 		{
2945 		  /* Input reloads can be inherited more often than
2946 		     output reloads can be removed, so penalize output
2947 		     reloads.  */
2948 		  if (!REG_P (op) || curr_static_id->operand[nop].type != OP_IN)
2949 		    {
2950 		      if (lra_dump_file != NULL)
2951 			fprintf
2952 			  (lra_dump_file,
2953 			   "            %d Non input pseudo reload: reject++\n",
2954 			   nop);
2955 		      reject++;
2956 		    }
2957 
2958 		  if (curr_static_id->operand[nop].type == OP_INOUT)
2959 		    {
2960 		      if (lra_dump_file != NULL)
2961 			fprintf
2962 			  (lra_dump_file,
2963 			   "            %d Input/Output reload: reject+=%d\n",
2964 			   nop, LRA_LOSER_COST_FACTOR);
2965 		      reject += LRA_LOSER_COST_FACTOR;
2966 		    }
2967 		}
2968 	    }
2969 
2970 	  if (early_clobber_p && ! scratch_p)
2971 	    {
2972 	      if (lra_dump_file != NULL)
2973 		fprintf (lra_dump_file,
2974 			 "            %d Early clobber: reject++\n", nop);
2975 	      reject++;
2976 	    }
2977 	  /* ??? We check early clobbers after processing all operands
2978 	     (see loop below) and there we update the costs more.
2979 	     Should we update the cost (may be approximately) here
2980 	     because of early clobber register reloads or it is a rare
2981 	     or non-important thing to be worth to do it.  */
2982 	  overall = (losers * LRA_LOSER_COST_FACTOR + reject
2983 		     - (addr_losers == losers ? static_reject : 0));
2984 	  if ((best_losers == 0 || losers != 0) && best_overall < overall)
2985             {
2986               if (lra_dump_file != NULL)
2987 		fprintf (lra_dump_file,
2988 			 "            alt=%d,overall=%d,losers=%d -- refuse\n",
2989 			 nalt, overall, losers);
2990               goto fail;
2991             }
2992 
2993 	  if (update_and_check_small_class_inputs (nop, nalt,
2994 						   this_alternative))
2995 	    {
2996 	      if (lra_dump_file != NULL)
2997 		fprintf (lra_dump_file,
2998 			 "            alt=%d, not enough small class regs -- refuse\n",
2999 			 nalt);
3000 	      goto fail;
3001 	    }
3002 	  curr_alt[nop] = this_alternative;
3003 	  curr_alt_set[nop] = this_alternative_set;
3004 	  curr_alt_win[nop] = this_alternative_win;
3005 	  curr_alt_match_win[nop] = this_alternative_match_win;
3006 	  curr_alt_offmemok[nop] = this_alternative_offmemok;
3007 	  curr_alt_matches[nop] = this_alternative_matches;
3008 
3009 	  if (this_alternative_matches >= 0
3010 	      && !did_match && !this_alternative_win)
3011 	    curr_alt_win[this_alternative_matches] = false;
3012 
3013 	  if (early_clobber_p && operand_reg[nop] != NULL_RTX)
3014 	    early_clobbered_nops[early_clobbered_regs_num++] = nop;
3015 	}
3016 
3017       if (curr_insn_set != NULL_RTX && n_operands == 2
3018 	  /* Prevent processing non-move insns.  */
3019 	  && (GET_CODE (SET_SRC (curr_insn_set)) == SUBREG
3020 	      || SET_SRC (curr_insn_set) == no_subreg_reg_operand[1])
3021 	  && ((! curr_alt_win[0] && ! curr_alt_win[1]
3022 	       && REG_P (no_subreg_reg_operand[0])
3023 	       && REG_P (no_subreg_reg_operand[1])
3024 	       && (reg_in_class_p (no_subreg_reg_operand[0], curr_alt[1])
3025 		   || reg_in_class_p (no_subreg_reg_operand[1], curr_alt[0])))
3026 	      || (! curr_alt_win[0] && curr_alt_win[1]
3027 		  && REG_P (no_subreg_reg_operand[1])
3028 		  /* Check that we reload memory not the memory
3029 		     address.  */
3030 		  && ! (curr_alt_offmemok[0]
3031 			&& MEM_P (no_subreg_reg_operand[0]))
3032 		  && reg_in_class_p (no_subreg_reg_operand[1], curr_alt[0]))
3033 	      || (curr_alt_win[0] && ! curr_alt_win[1]
3034 		  && REG_P (no_subreg_reg_operand[0])
3035 		  /* Check that we reload memory not the memory
3036 		     address.  */
3037 		  && ! (curr_alt_offmemok[1]
3038 			&& MEM_P (no_subreg_reg_operand[1]))
3039 		  && reg_in_class_p (no_subreg_reg_operand[0], curr_alt[1])
3040 		  && (! CONST_POOL_OK_P (curr_operand_mode[1],
3041 					 no_subreg_reg_operand[1])
3042 		      || (targetm.preferred_reload_class
3043 			  (no_subreg_reg_operand[1],
3044 			   (enum reg_class) curr_alt[1]) != NO_REGS))
3045 		  /* If it is a result of recent elimination in move
3046 		     insn we can transform it into an add still by
3047 		     using this alternative.  */
3048 		  && GET_CODE (no_subreg_reg_operand[1]) != PLUS
3049 		  /* Likewise if the source has been replaced with an
3050 		     equivalent value.  This only happens once -- the reload
3051 		     will use the equivalent value instead of the register it
3052 		     replaces -- so there should be no danger of cycling.  */
3053 		  && !equiv_substition_p[1])))
3054 	{
3055 	  /* We have a move insn and a new reload insn will be similar
3056 	     to the current insn.  We should avoid such situation as
3057 	     it results in LRA cycling.  */
3058 	  if (lra_dump_file != NULL)
3059 	    fprintf (lra_dump_file,
3060 		     "            Cycle danger: overall += LRA_MAX_REJECT\n");
3061 	  overall += LRA_MAX_REJECT;
3062 	}
3063       ok_p = true;
3064       curr_alt_dont_inherit_ops_num = 0;
3065       for (nop = 0; nop < early_clobbered_regs_num; nop++)
3066 	{
3067 	  int i, j, clobbered_hard_regno, first_conflict_j, last_conflict_j;
3068 	  HARD_REG_SET temp_set;
3069 
3070 	  i = early_clobbered_nops[nop];
3071 	  if ((! curr_alt_win[i] && ! curr_alt_match_win[i])
3072 	      || hard_regno[i] < 0)
3073 	    continue;
3074 	  lra_assert (operand_reg[i] != NULL_RTX);
3075 	  clobbered_hard_regno = hard_regno[i];
3076 	  CLEAR_HARD_REG_SET (temp_set);
3077 	  add_to_hard_reg_set (&temp_set, biggest_mode[i], clobbered_hard_regno);
3078 	  first_conflict_j = last_conflict_j = -1;
3079 	  for (j = 0; j < n_operands; j++)
3080 	    if (j == i
3081 		/* We don't want process insides of match_operator and
3082 		   match_parallel because otherwise we would process
3083 		   their operands once again generating a wrong
3084 		   code.  */
3085 		|| curr_static_id->operand[j].is_operator)
3086 	      continue;
3087 	    else if ((curr_alt_matches[j] == i && curr_alt_match_win[j])
3088 		     || (curr_alt_matches[i] == j && curr_alt_match_win[i]))
3089 	      continue;
3090 	    /* If we don't reload j-th operand, check conflicts.  */
3091 	    else if ((curr_alt_win[j] || curr_alt_match_win[j])
3092 		     && uses_hard_regs_p (*curr_id->operand_loc[j], temp_set))
3093 	      {
3094 		if (first_conflict_j < 0)
3095 		  first_conflict_j = j;
3096 		last_conflict_j = j;
3097 		/* Both the earlyclobber operand and conflicting operand
3098 		   cannot both be user defined hard registers.  */
3099 		if (HARD_REGISTER_P (operand_reg[i])
3100 		    && REG_USERVAR_P (operand_reg[i])
3101 		    && operand_reg[j] != NULL_RTX
3102 		    && HARD_REGISTER_P (operand_reg[j])
3103 		    && REG_USERVAR_P (operand_reg[j]))
3104 		  {
3105 		    /* For asm, let curr_insn_transform diagnose it.  */
3106 		    if (INSN_CODE (curr_insn) < 0)
3107 		      return false;
3108 		    fatal_insn ("unable to generate reloads for "
3109 				"impossible constraints:", curr_insn);
3110 		  }
3111 	      }
3112 	  if (last_conflict_j < 0)
3113 	    continue;
3114 
3115 	  /* If an earlyclobber operand conflicts with another non-matching
3116 	     operand (ie, they have been assigned the same hard register),
3117 	     then it is better to reload the other operand, as there may
3118 	     exist yet another operand with a matching constraint associated
3119 	     with the earlyclobber operand.  However, if one of the operands
3120 	     is an explicit use of a hard register, then we must reload the
3121 	     other non-hard register operand.  */
3122 	  if (HARD_REGISTER_P (operand_reg[i])
3123 	      || (first_conflict_j == last_conflict_j
3124 		  && operand_reg[last_conflict_j] != NULL_RTX
3125 		  && !curr_alt_match_win[last_conflict_j]
3126 		  && !HARD_REGISTER_P (operand_reg[last_conflict_j])))
3127 	    {
3128 	      curr_alt_win[last_conflict_j] = false;
3129 	      curr_alt_dont_inherit_ops[curr_alt_dont_inherit_ops_num++]
3130 		= last_conflict_j;
3131 	      losers++;
3132 	      if (lra_dump_file != NULL)
3133 		fprintf
3134 		  (lra_dump_file,
3135 		   "            %d Conflict early clobber reload: reject--\n",
3136 		   i);
3137 	    }
3138 	  else
3139 	    {
3140 	      /* We need to reload early clobbered register and the
3141 		 matched registers.  */
3142 	      for (j = 0; j < n_operands; j++)
3143 		if (curr_alt_matches[j] == i)
3144 		  {
3145 		    curr_alt_match_win[j] = false;
3146 		    losers++;
3147 		    overall += LRA_LOSER_COST_FACTOR;
3148 		  }
3149 	      if (! curr_alt_match_win[i])
3150 		curr_alt_dont_inherit_ops[curr_alt_dont_inherit_ops_num++] = i;
3151 	      else
3152 		{
3153 		  /* Remember pseudos used for match reloads are never
3154 		     inherited.  */
3155 		  lra_assert (curr_alt_matches[i] >= 0);
3156 		  curr_alt_win[curr_alt_matches[i]] = false;
3157 		}
3158 	      curr_alt_win[i] = curr_alt_match_win[i] = false;
3159 	      losers++;
3160 	      if (lra_dump_file != NULL)
3161 		fprintf
3162 		  (lra_dump_file,
3163 		   "            %d Matched conflict early clobber reloads: "
3164 		   "reject--\n",
3165 		   i);
3166 	    }
3167 	  /* Early clobber was already reflected in REJECT. */
3168 	  if (!matching_early_clobber[i])
3169 	    {
3170 	      lra_assert (reject > 0);
3171 	      reject--;
3172 	      matching_early_clobber[i] = 1;
3173 	    }
3174 	  overall += LRA_LOSER_COST_FACTOR - 1;
3175 	}
3176       if (lra_dump_file != NULL)
3177 	fprintf (lra_dump_file, "          alt=%d,overall=%d,losers=%d,rld_nregs=%d\n",
3178 		 nalt, overall, losers, reload_nregs);
3179 
3180       /* If this alternative can be made to work by reloading, and it
3181 	 needs less reloading than the others checked so far, record
3182 	 it as the chosen goal for reloading.  */
3183       if ((best_losers != 0 && losers == 0)
3184 	  || (((best_losers == 0 && losers == 0)
3185 	       || (best_losers != 0 && losers != 0))
3186 	      && (best_overall > overall
3187 		  || (best_overall == overall
3188 		      /* If the cost of the reloads is the same,
3189 			 prefer alternative which requires minimal
3190 			 number of reload regs.  */
3191 		      && (reload_nregs < best_reload_nregs
3192 			  || (reload_nregs == best_reload_nregs
3193 			      && (best_reload_sum < reload_sum
3194 				  || (best_reload_sum == reload_sum
3195 				      && nalt < goal_alt_number))))))))
3196 	{
3197 	  for (nop = 0; nop < n_operands; nop++)
3198 	    {
3199 	      goal_alt_win[nop] = curr_alt_win[nop];
3200 	      goal_alt_match_win[nop] = curr_alt_match_win[nop];
3201 	      goal_alt_matches[nop] = curr_alt_matches[nop];
3202 	      goal_alt[nop] = curr_alt[nop];
3203 	      goal_alt_offmemok[nop] = curr_alt_offmemok[nop];
3204 	    }
3205 	  goal_alt_dont_inherit_ops_num = curr_alt_dont_inherit_ops_num;
3206 	  for (nop = 0; nop < curr_alt_dont_inherit_ops_num; nop++)
3207 	    goal_alt_dont_inherit_ops[nop] = curr_alt_dont_inherit_ops[nop];
3208 	  goal_alt_swapped = curr_swapped;
3209 	  best_overall = overall;
3210 	  best_losers = losers;
3211 	  best_reload_nregs = reload_nregs;
3212 	  best_reload_sum = reload_sum;
3213 	  goal_alt_number = nalt;
3214 	}
3215       if (losers == 0)
3216 	/* Everything is satisfied.  Do not process alternatives
3217 	   anymore.  */
3218 	break;
3219     fail:
3220       ;
3221     }
3222   return ok_p;
3223 }
3224 
3225 /* Make reload base reg from address AD.  */
3226 static rtx
base_to_reg(struct address_info * ad)3227 base_to_reg (struct address_info *ad)
3228 {
3229   enum reg_class cl;
3230   int code = -1;
3231   rtx new_inner = NULL_RTX;
3232   rtx new_reg = NULL_RTX;
3233   rtx_insn *insn;
3234   rtx_insn *last_insn = get_last_insn();
3235 
3236   lra_assert (ad->disp == ad->disp_term);
3237   cl = base_reg_class (ad->mode, ad->as, ad->base_outer_code,
3238                        get_index_code (ad));
3239   new_reg = lra_create_new_reg (GET_MODE (*ad->base), NULL_RTX,
3240                                 cl, "base");
3241   new_inner = simplify_gen_binary (PLUS, GET_MODE (new_reg), new_reg,
3242                                    ad->disp_term == NULL
3243                                    ? const0_rtx
3244                                    : *ad->disp_term);
3245   if (!valid_address_p (ad->mode, new_inner, ad->as))
3246     return NULL_RTX;
3247   insn = emit_insn (gen_rtx_SET (new_reg, *ad->base));
3248   code = recog_memoized (insn);
3249   if (code < 0)
3250     {
3251       delete_insns_since (last_insn);
3252       return NULL_RTX;
3253     }
3254 
3255   return new_inner;
3256 }
3257 
3258 /* Make reload base reg + DISP from address AD.  Return the new pseudo.  */
3259 static rtx
base_plus_disp_to_reg(struct address_info * ad,rtx disp)3260 base_plus_disp_to_reg (struct address_info *ad, rtx disp)
3261 {
3262   enum reg_class cl;
3263   rtx new_reg;
3264 
3265   lra_assert (ad->base == ad->base_term);
3266   cl = base_reg_class (ad->mode, ad->as, ad->base_outer_code,
3267 		       get_index_code (ad));
3268   new_reg = lra_create_new_reg (GET_MODE (*ad->base_term), NULL_RTX,
3269 				cl, "base + disp");
3270   lra_emit_add (new_reg, *ad->base_term, disp);
3271   return new_reg;
3272 }
3273 
3274 /* Make reload of index part of address AD.  Return the new
3275    pseudo.  */
3276 static rtx
index_part_to_reg(struct address_info * ad)3277 index_part_to_reg (struct address_info *ad)
3278 {
3279   rtx new_reg;
3280 
3281   new_reg = lra_create_new_reg (GET_MODE (*ad->index), NULL_RTX,
3282 				INDEX_REG_CLASS, "index term");
3283   expand_mult (GET_MODE (*ad->index), *ad->index_term,
3284 	       GEN_INT (get_index_scale (ad)), new_reg, 1);
3285   return new_reg;
3286 }
3287 
3288 /* Return true if we can add a displacement to address AD, even if that
3289    makes the address invalid.  The fix-up code requires any new address
3290    to be the sum of the BASE_TERM, INDEX and DISP_TERM fields.  */
3291 static bool
can_add_disp_p(struct address_info * ad)3292 can_add_disp_p (struct address_info *ad)
3293 {
3294   return (!ad->autoinc_p
3295 	  && ad->segment == NULL
3296 	  && ad->base == ad->base_term
3297 	  && ad->disp == ad->disp_term);
3298 }
3299 
3300 /* Make equiv substitution in address AD.  Return true if a substitution
3301    was made.  */
3302 static bool
equiv_address_substitution(struct address_info * ad)3303 equiv_address_substitution (struct address_info *ad)
3304 {
3305   rtx base_reg, new_base_reg, index_reg, new_index_reg, *base_term, *index_term;
3306   poly_int64 disp;
3307   HOST_WIDE_INT scale;
3308   bool change_p;
3309 
3310   base_term = strip_subreg (ad->base_term);
3311   if (base_term == NULL)
3312     base_reg = new_base_reg = NULL_RTX;
3313   else
3314     {
3315       base_reg = *base_term;
3316       new_base_reg = get_equiv_with_elimination (base_reg, curr_insn);
3317     }
3318   index_term = strip_subreg (ad->index_term);
3319   if (index_term == NULL)
3320     index_reg = new_index_reg = NULL_RTX;
3321   else
3322     {
3323       index_reg = *index_term;
3324       new_index_reg = get_equiv_with_elimination (index_reg, curr_insn);
3325     }
3326   if (base_reg == new_base_reg && index_reg == new_index_reg)
3327     return false;
3328   disp = 0;
3329   change_p = false;
3330   if (lra_dump_file != NULL)
3331     {
3332       fprintf (lra_dump_file, "Changing address in insn %d ",
3333 	       INSN_UID (curr_insn));
3334       dump_value_slim (lra_dump_file, *ad->outer, 1);
3335     }
3336   if (base_reg != new_base_reg)
3337     {
3338       poly_int64 offset;
3339       if (REG_P (new_base_reg))
3340 	{
3341 	  *base_term = new_base_reg;
3342 	  change_p = true;
3343 	}
3344       else if (GET_CODE (new_base_reg) == PLUS
3345 	       && REG_P (XEXP (new_base_reg, 0))
3346 	       && poly_int_rtx_p (XEXP (new_base_reg, 1), &offset)
3347 	       && can_add_disp_p (ad))
3348 	{
3349 	  disp += offset;
3350 	  *base_term = XEXP (new_base_reg, 0);
3351 	  change_p = true;
3352 	}
3353       if (ad->base_term2 != NULL)
3354 	*ad->base_term2 = *ad->base_term;
3355     }
3356   if (index_reg != new_index_reg)
3357     {
3358       poly_int64 offset;
3359       if (REG_P (new_index_reg))
3360 	{
3361 	  *index_term = new_index_reg;
3362 	  change_p = true;
3363 	}
3364       else if (GET_CODE (new_index_reg) == PLUS
3365 	       && REG_P (XEXP (new_index_reg, 0))
3366 	       && poly_int_rtx_p (XEXP (new_index_reg, 1), &offset)
3367 	       && can_add_disp_p (ad)
3368 	       && (scale = get_index_scale (ad)))
3369 	{
3370 	  disp += offset * scale;
3371 	  *index_term = XEXP (new_index_reg, 0);
3372 	  change_p = true;
3373 	}
3374     }
3375   if (maybe_ne (disp, 0))
3376     {
3377       if (ad->disp != NULL)
3378 	*ad->disp = plus_constant (GET_MODE (*ad->inner), *ad->disp, disp);
3379       else
3380 	{
3381 	  *ad->inner = plus_constant (GET_MODE (*ad->inner), *ad->inner, disp);
3382 	  update_address (ad);
3383 	}
3384       change_p = true;
3385     }
3386   if (lra_dump_file != NULL)
3387     {
3388       if (! change_p)
3389 	fprintf (lra_dump_file, " -- no change\n");
3390       else
3391 	{
3392 	  fprintf (lra_dump_file, " on equiv ");
3393 	  dump_value_slim (lra_dump_file, *ad->outer, 1);
3394 	  fprintf (lra_dump_file, "\n");
3395 	}
3396     }
3397   return change_p;
3398 }
3399 
3400 /* Skip all modifiers and whitespaces in constraint STR and return the
3401    result.  */
3402 static const char *
skip_constraint_modifiers(const char * str)3403 skip_constraint_modifiers (const char *str)
3404 {
3405   for (;;str++)
3406     switch (*str)
3407       {
3408       case '+': case '&' : case '=': case '*': case ' ': case '\t':
3409       case '$': case '^' : case '%': case '?': case '!':
3410 	break;
3411       default: return str;
3412       }
3413 }
3414 
3415 /* Major function to make reloads for an address in operand NOP or
3416    check its correctness (If CHECK_ONLY_P is true). The supported
3417    cases are:
3418 
3419    1) an address that existed before LRA started, at which point it
3420    must have been valid.  These addresses are subject to elimination
3421    and may have become invalid due to the elimination offset being out
3422    of range.
3423 
3424    2) an address created by forcing a constant to memory
3425    (force_const_to_mem).  The initial form of these addresses might
3426    not be valid, and it is this function's job to make them valid.
3427 
3428    3) a frame address formed from a register and a (possibly zero)
3429    constant offset.  As above, these addresses might not be valid and
3430    this function must make them so.
3431 
3432    Add reloads to the lists *BEFORE and *AFTER.  We might need to add
3433    reloads to *AFTER because of inc/dec, {pre, post} modify in the
3434    address.  Return true for any RTL change.
3435 
3436    The function is a helper function which does not produce all
3437    transformations (when CHECK_ONLY_P is false) which can be
3438    necessary.  It does just basic steps.  To do all necessary
3439    transformations use function process_address.  */
3440 static bool
process_address_1(int nop,bool check_only_p,rtx_insn ** before,rtx_insn ** after)3441 process_address_1 (int nop, bool check_only_p,
3442 		   rtx_insn **before, rtx_insn **after)
3443 {
3444   struct address_info ad;
3445   rtx new_reg;
3446   HOST_WIDE_INT scale;
3447   rtx op = *curr_id->operand_loc[nop];
3448   rtx mem = extract_mem_from_operand (op);
3449   const char *constraint;
3450   enum constraint_num cn;
3451   bool change_p = false;
3452 
3453   if (MEM_P (mem)
3454       && GET_MODE (mem) == BLKmode
3455       && GET_CODE (XEXP (mem, 0)) == SCRATCH)
3456     return false;
3457 
3458   constraint
3459     = skip_constraint_modifiers (curr_static_id->operand[nop].constraint);
3460   if (IN_RANGE (constraint[0], '0', '9'))
3461     {
3462       char *end;
3463       unsigned long dup = strtoul (constraint, &end, 10);
3464       constraint
3465 	= skip_constraint_modifiers (curr_static_id->operand[dup].constraint);
3466     }
3467   cn = lookup_constraint (*constraint == '\0' ? "X" : constraint);
3468   /* If we have several alternatives or/and several constraints in an
3469      alternative and we can not say at this stage what constraint will be used,
3470      use unknown constraint.  The exception is an address constraint.  If
3471      operand has one address constraint, probably all others constraints are
3472      address ones.  */
3473   if (constraint[0] != '\0' && get_constraint_type (cn) != CT_ADDRESS
3474       && *skip_constraint_modifiers (constraint
3475 				     + CONSTRAINT_LEN (constraint[0],
3476 						       constraint)) != '\0')
3477     cn = CONSTRAINT__UNKNOWN;
3478   if (insn_extra_address_constraint (cn)
3479       /* When we find an asm operand with an address constraint that
3480 	 doesn't satisfy address_operand to begin with, we clear
3481 	 is_address, so that we don't try to make a non-address fit.
3482 	 If the asm statement got this far, it's because other
3483 	 constraints are available, and we'll use them, disregarding
3484 	 the unsatisfiable address ones.  */
3485       && curr_static_id->operand[nop].is_address)
3486     decompose_lea_address (&ad, curr_id->operand_loc[nop]);
3487   /* Do not attempt to decompose arbitrary addresses generated by combine
3488      for asm operands with loose constraints, e.g 'X'.
3489      Need to extract memory from op for special memory constraint,
3490      i.e. bcst_mem_operand in i386 backend.  */
3491   else if (MEM_P (mem)
3492 	   && !(INSN_CODE (curr_insn) < 0
3493 		&& get_constraint_type (cn) == CT_FIXED_FORM
3494 		&& constraint_satisfied_p (op, cn)))
3495     decompose_mem_address (&ad, mem);
3496   else if (GET_CODE (op) == SUBREG
3497 	   && MEM_P (SUBREG_REG (op)))
3498     decompose_mem_address (&ad, SUBREG_REG (op));
3499   else
3500     return false;
3501   /* If INDEX_REG_CLASS is assigned to base_term already and isn't to
3502      index_term, swap them so to avoid assigning INDEX_REG_CLASS to both
3503      when INDEX_REG_CLASS is a single register class.  */
3504   if (ad.base_term != NULL
3505       && ad.index_term != NULL
3506       && ira_class_hard_regs_num[INDEX_REG_CLASS] == 1
3507       && REG_P (*ad.base_term)
3508       && REG_P (*ad.index_term)
3509       && in_class_p (*ad.base_term, INDEX_REG_CLASS, NULL)
3510       && ! in_class_p (*ad.index_term, INDEX_REG_CLASS, NULL))
3511     {
3512       std::swap (ad.base, ad.index);
3513       std::swap (ad.base_term, ad.index_term);
3514     }
3515   if (! check_only_p)
3516     change_p = equiv_address_substitution (&ad);
3517   if (ad.base_term != NULL
3518       && (process_addr_reg
3519 	  (ad.base_term, check_only_p, before,
3520 	   (ad.autoinc_p
3521 	    && !(REG_P (*ad.base_term)
3522 		 && find_regno_note (curr_insn, REG_DEAD,
3523 				     REGNO (*ad.base_term)) != NULL_RTX)
3524 	    ? after : NULL),
3525 	   base_reg_class (ad.mode, ad.as, ad.base_outer_code,
3526 			   get_index_code (&ad)))))
3527     {
3528       change_p = true;
3529       if (ad.base_term2 != NULL)
3530 	*ad.base_term2 = *ad.base_term;
3531     }
3532   if (ad.index_term != NULL
3533       && process_addr_reg (ad.index_term, check_only_p,
3534 			   before, NULL, INDEX_REG_CLASS))
3535     change_p = true;
3536 
3537   /* Target hooks sometimes don't treat extra-constraint addresses as
3538      legitimate address_operands, so handle them specially.  */
3539   if (insn_extra_address_constraint (cn)
3540       && satisfies_address_constraint_p (&ad, cn))
3541     return change_p;
3542 
3543   if (check_only_p)
3544     return change_p;
3545 
3546   /* There are three cases where the shape of *AD.INNER may now be invalid:
3547 
3548      1) the original address was valid, but either elimination or
3549      equiv_address_substitution was applied and that made
3550      the address invalid.
3551 
3552      2) the address is an invalid symbolic address created by
3553      force_const_to_mem.
3554 
3555      3) the address is a frame address with an invalid offset.
3556 
3557      4) the address is a frame address with an invalid base.
3558 
3559      All these cases involve a non-autoinc address, so there is no
3560      point revalidating other types.  */
3561   if (ad.autoinc_p || valid_address_p (op, &ad, cn))
3562     return change_p;
3563 
3564   /* Any index existed before LRA started, so we can assume that the
3565      presence and shape of the index is valid.  */
3566   push_to_sequence (*before);
3567   lra_assert (ad.disp == ad.disp_term);
3568   if (ad.base == NULL)
3569     {
3570       if (ad.index == NULL)
3571 	{
3572 	  rtx_insn *insn;
3573 	  rtx_insn *last = get_last_insn ();
3574 	  int code = -1;
3575 	  enum reg_class cl = base_reg_class (ad.mode, ad.as,
3576 					      SCRATCH, SCRATCH);
3577 	  rtx addr = *ad.inner;
3578 
3579 	  new_reg = lra_create_new_reg (Pmode, NULL_RTX, cl, "addr");
3580 	  if (HAVE_lo_sum)
3581 	    {
3582 	      /* addr => lo_sum (new_base, addr), case (2) above.  */
3583 	      insn = emit_insn (gen_rtx_SET
3584 				(new_reg,
3585 				 gen_rtx_HIGH (Pmode, copy_rtx (addr))));
3586 	      code = recog_memoized (insn);
3587 	      if (code >= 0)
3588 		{
3589 		  *ad.inner = gen_rtx_LO_SUM (Pmode, new_reg, addr);
3590 		  if (!valid_address_p (op, &ad, cn))
3591 		    {
3592 		      /* Try to put lo_sum into register.  */
3593 		      insn = emit_insn (gen_rtx_SET
3594 					(new_reg,
3595 					 gen_rtx_LO_SUM (Pmode, new_reg, addr)));
3596 		      code = recog_memoized (insn);
3597 		      if (code >= 0)
3598 			{
3599 			  *ad.inner = new_reg;
3600 			  if (!valid_address_p (op, &ad, cn))
3601 			    {
3602 			      *ad.inner = addr;
3603 			      code = -1;
3604 			    }
3605 			}
3606 
3607 		    }
3608 		}
3609 	      if (code < 0)
3610 		delete_insns_since (last);
3611 	    }
3612 
3613 	  if (code < 0)
3614 	    {
3615 	      /* addr => new_base, case (2) above.  */
3616 	      lra_emit_move (new_reg, addr);
3617 
3618 	      for (insn = last == NULL_RTX ? get_insns () : NEXT_INSN (last);
3619 		   insn != NULL_RTX;
3620 		   insn = NEXT_INSN (insn))
3621 		if (recog_memoized (insn) < 0)
3622 		  break;
3623 	      if (insn != NULL_RTX)
3624 		{
3625 		  /* Do nothing if we cannot generate right insns.
3626 		     This is analogous to reload pass behavior.  */
3627 		  delete_insns_since (last);
3628 		  end_sequence ();
3629 		  return false;
3630 		}
3631 	      *ad.inner = new_reg;
3632 	    }
3633 	}
3634       else
3635 	{
3636 	  /* index * scale + disp => new base + index * scale,
3637 	     case (1) above.  */
3638 	  enum reg_class cl = base_reg_class (ad.mode, ad.as, PLUS,
3639 					      GET_CODE (*ad.index));
3640 
3641 	  lra_assert (INDEX_REG_CLASS != NO_REGS);
3642 	  new_reg = lra_create_new_reg (Pmode, NULL_RTX, cl, "disp");
3643 	  lra_emit_move (new_reg, *ad.disp);
3644 	  *ad.inner = simplify_gen_binary (PLUS, GET_MODE (new_reg),
3645 					   new_reg, *ad.index);
3646 	}
3647     }
3648   else if (ad.index == NULL)
3649     {
3650       int regno;
3651       enum reg_class cl;
3652       rtx set;
3653       rtx_insn *insns, *last_insn;
3654       /* Try to reload base into register only if the base is invalid
3655          for the address but with valid offset, case (4) above.  */
3656       start_sequence ();
3657       new_reg = base_to_reg (&ad);
3658 
3659       /* base + disp => new base, cases (1) and (3) above.  */
3660       /* Another option would be to reload the displacement into an
3661 	 index register.  However, postreload has code to optimize
3662 	 address reloads that have the same base and different
3663 	 displacements, so reloading into an index register would
3664 	 not necessarily be a win.  */
3665       if (new_reg == NULL_RTX)
3666 	{
3667 	  /* See if the target can split the displacement into a
3668 	     legitimate new displacement from a local anchor.  */
3669 	  gcc_assert (ad.disp == ad.disp_term);
3670 	  poly_int64 orig_offset;
3671 	  rtx offset1, offset2;
3672 	  if (poly_int_rtx_p (*ad.disp, &orig_offset)
3673 	      && targetm.legitimize_address_displacement (&offset1, &offset2,
3674 							  orig_offset,
3675 							  ad.mode))
3676 	    {
3677 	      new_reg = base_plus_disp_to_reg (&ad, offset1);
3678 	      new_reg = gen_rtx_PLUS (GET_MODE (new_reg), new_reg, offset2);
3679 	    }
3680 	  else
3681 	    new_reg = base_plus_disp_to_reg (&ad, *ad.disp);
3682 	}
3683       insns = get_insns ();
3684       last_insn = get_last_insn ();
3685       /* If we generated at least two insns, try last insn source as
3686 	 an address.  If we succeed, we generate one less insn.  */
3687       if (REG_P (new_reg)
3688 	  && last_insn != insns
3689 	  && (set = single_set (last_insn)) != NULL_RTX
3690 	  && GET_CODE (SET_SRC (set)) == PLUS
3691 	  && REG_P (XEXP (SET_SRC (set), 0))
3692 	  && CONSTANT_P (XEXP (SET_SRC (set), 1)))
3693 	{
3694 	  *ad.inner = SET_SRC (set);
3695 	  if (valid_address_p (op, &ad, cn))
3696 	    {
3697 	      *ad.base_term = XEXP (SET_SRC (set), 0);
3698 	      *ad.disp_term = XEXP (SET_SRC (set), 1);
3699 	      cl = base_reg_class (ad.mode, ad.as, ad.base_outer_code,
3700 				   get_index_code (&ad));
3701 	      regno = REGNO (*ad.base_term);
3702 	      if (regno >= FIRST_PSEUDO_REGISTER
3703 		  && cl != lra_get_allocno_class (regno))
3704 		lra_change_class (regno, cl, "      Change to", true);
3705 	      new_reg = SET_SRC (set);
3706 	      delete_insns_since (PREV_INSN (last_insn));
3707 	    }
3708 	}
3709       end_sequence ();
3710       emit_insn (insns);
3711       *ad.inner = new_reg;
3712     }
3713   else if (ad.disp_term != NULL)
3714     {
3715       /* base + scale * index + disp => new base + scale * index,
3716 	 case (1) above.  */
3717       gcc_assert (ad.disp == ad.disp_term);
3718       new_reg = base_plus_disp_to_reg (&ad, *ad.disp);
3719       *ad.inner = simplify_gen_binary (PLUS, GET_MODE (new_reg),
3720 				       new_reg, *ad.index);
3721     }
3722   else if ((scale = get_index_scale (&ad)) == 1)
3723     {
3724       /* The last transformation to one reg will be made in
3725 	 curr_insn_transform function.  */
3726       end_sequence ();
3727       return false;
3728     }
3729   else if (scale != 0)
3730     {
3731       /* base + scale * index => base + new_reg,
3732 	 case (1) above.
3733       Index part of address may become invalid.  For example, we
3734       changed pseudo on the equivalent memory and a subreg of the
3735       pseudo onto the memory of different mode for which the scale is
3736       prohibitted.  */
3737       new_reg = index_part_to_reg (&ad);
3738       *ad.inner = simplify_gen_binary (PLUS, GET_MODE (new_reg),
3739 				       *ad.base_term, new_reg);
3740     }
3741   else
3742     {
3743       enum reg_class cl = base_reg_class (ad.mode, ad.as,
3744 					  SCRATCH, SCRATCH);
3745       rtx addr = *ad.inner;
3746 
3747       new_reg = lra_create_new_reg (Pmode, NULL_RTX, cl, "addr");
3748       /* addr => new_base.  */
3749       lra_emit_move (new_reg, addr);
3750       *ad.inner = new_reg;
3751     }
3752   *before = get_insns ();
3753   end_sequence ();
3754   return true;
3755 }
3756 
3757 /* If CHECK_ONLY_P is false, do address reloads until it is necessary.
3758    Use process_address_1 as a helper function.  Return true for any
3759    RTL changes.
3760 
3761    If CHECK_ONLY_P is true, just check address correctness.  Return
3762    false if the address correct.  */
3763 static bool
process_address(int nop,bool check_only_p,rtx_insn ** before,rtx_insn ** after)3764 process_address (int nop, bool check_only_p,
3765 		 rtx_insn **before, rtx_insn **after)
3766 {
3767   bool res = false;
3768 
3769   while (process_address_1 (nop, check_only_p, before, after))
3770     {
3771       if (check_only_p)
3772 	return true;
3773       res = true;
3774     }
3775   return res;
3776 }
3777 
3778 /* Emit insns to reload VALUE into a new register.  VALUE is an
3779    auto-increment or auto-decrement RTX whose operand is a register or
3780    memory location; so reloading involves incrementing that location.
3781    IN is either identical to VALUE, or some cheaper place to reload
3782    value being incremented/decremented from.
3783 
3784    INC_AMOUNT is the number to increment or decrement by (always
3785    positive and ignored for POST_MODIFY/PRE_MODIFY).
3786 
3787    Return pseudo containing the result.	 */
3788 static rtx
emit_inc(enum reg_class new_rclass,rtx in,rtx value,poly_int64 inc_amount)3789 emit_inc (enum reg_class new_rclass, rtx in, rtx value, poly_int64 inc_amount)
3790 {
3791   /* REG or MEM to be copied and incremented.  */
3792   rtx incloc = XEXP (value, 0);
3793   /* Nonzero if increment after copying.  */
3794   int post = (GET_CODE (value) == POST_DEC || GET_CODE (value) == POST_INC
3795 	      || GET_CODE (value) == POST_MODIFY);
3796   rtx_insn *last;
3797   rtx inc;
3798   rtx_insn *add_insn;
3799   int code;
3800   rtx real_in = in == value ? incloc : in;
3801   rtx result;
3802   bool plus_p = true;
3803 
3804   if (GET_CODE (value) == PRE_MODIFY || GET_CODE (value) == POST_MODIFY)
3805     {
3806       lra_assert (GET_CODE (XEXP (value, 1)) == PLUS
3807 		  || GET_CODE (XEXP (value, 1)) == MINUS);
3808       lra_assert (rtx_equal_p (XEXP (XEXP (value, 1), 0), XEXP (value, 0)));
3809       plus_p = GET_CODE (XEXP (value, 1)) == PLUS;
3810       inc = XEXP (XEXP (value, 1), 1);
3811     }
3812   else
3813     {
3814       if (GET_CODE (value) == PRE_DEC || GET_CODE (value) == POST_DEC)
3815 	inc_amount = -inc_amount;
3816 
3817       inc = gen_int_mode (inc_amount, GET_MODE (value));
3818     }
3819 
3820   if (! post && REG_P (incloc))
3821     result = incloc;
3822   else
3823     result = lra_create_new_reg (GET_MODE (value), value, new_rclass,
3824 				 "INC/DEC result");
3825 
3826   if (real_in != result)
3827     {
3828       /* First copy the location to the result register.  */
3829       lra_assert (REG_P (result));
3830       emit_insn (gen_move_insn (result, real_in));
3831     }
3832 
3833   /* We suppose that there are insns to add/sub with the constant
3834      increment permitted in {PRE/POST)_{DEC/INC/MODIFY}.  At least the
3835      old reload worked with this assumption.  If the assumption
3836      becomes wrong, we should use approach in function
3837      base_plus_disp_to_reg.  */
3838   if (in == value)
3839     {
3840       /* See if we can directly increment INCLOC.  */
3841       last = get_last_insn ();
3842       add_insn = emit_insn (plus_p
3843 			    ? gen_add2_insn (incloc, inc)
3844 			    : gen_sub2_insn (incloc, inc));
3845 
3846       code = recog_memoized (add_insn);
3847       if (code >= 0)
3848 	{
3849 	  if (! post && result != incloc)
3850 	    emit_insn (gen_move_insn (result, incloc));
3851 	  return result;
3852 	}
3853       delete_insns_since (last);
3854     }
3855 
3856   /* If couldn't do the increment directly, must increment in RESULT.
3857      The way we do this depends on whether this is pre- or
3858      post-increment.  For pre-increment, copy INCLOC to the reload
3859      register, increment it there, then save back.  */
3860   if (! post)
3861     {
3862       if (real_in != result)
3863 	emit_insn (gen_move_insn (result, real_in));
3864       if (plus_p)
3865 	emit_insn (gen_add2_insn (result, inc));
3866       else
3867 	emit_insn (gen_sub2_insn (result, inc));
3868       if (result != incloc)
3869 	emit_insn (gen_move_insn (incloc, result));
3870     }
3871   else
3872     {
3873       /* Post-increment.
3874 
3875 	 Because this might be a jump insn or a compare, and because
3876 	 RESULT may not be available after the insn in an input
3877 	 reload, we must do the incrementing before the insn being
3878 	 reloaded for.
3879 
3880 	 We have already copied IN to RESULT.  Increment the copy in
3881 	 RESULT, save that back, then decrement RESULT so it has
3882 	 the original value.  */
3883       if (plus_p)
3884 	emit_insn (gen_add2_insn (result, inc));
3885       else
3886 	emit_insn (gen_sub2_insn (result, inc));
3887       emit_insn (gen_move_insn (incloc, result));
3888       /* Restore non-modified value for the result.  We prefer this
3889 	 way because it does not require an additional hard
3890 	 register.  */
3891       if (plus_p)
3892 	{
3893 	  poly_int64 offset;
3894 	  if (poly_int_rtx_p (inc, &offset))
3895 	    emit_insn (gen_add2_insn (result,
3896 				      gen_int_mode (-offset,
3897 						    GET_MODE (result))));
3898 	  else
3899 	    emit_insn (gen_sub2_insn (result, inc));
3900 	}
3901       else
3902 	emit_insn (gen_add2_insn (result, inc));
3903     }
3904   return result;
3905 }
3906 
3907 /* Return true if the current move insn does not need processing as we
3908    already know that it satisfies its constraints.  */
3909 static bool
simple_move_p(void)3910 simple_move_p (void)
3911 {
3912   rtx dest, src;
3913   enum reg_class dclass, sclass;
3914 
3915   lra_assert (curr_insn_set != NULL_RTX);
3916   dest = SET_DEST (curr_insn_set);
3917   src = SET_SRC (curr_insn_set);
3918 
3919   /* If the instruction has multiple sets we need to process it even if it
3920      is single_set.  This can happen if one or more of the SETs are dead.
3921      See PR73650.  */
3922   if (multiple_sets (curr_insn))
3923     return false;
3924 
3925   return ((dclass = get_op_class (dest)) != NO_REGS
3926 	  && (sclass = get_op_class (src)) != NO_REGS
3927 	  /* The backend guarantees that register moves of cost 2
3928 	     never need reloads.  */
3929 	  && targetm.register_move_cost (GET_MODE (src), sclass, dclass) == 2);
3930  }
3931 
3932 /* Swap operands NOP and NOP + 1. */
3933 static inline void
swap_operands(int nop)3934 swap_operands (int nop)
3935 {
3936   std::swap (curr_operand_mode[nop], curr_operand_mode[nop + 1]);
3937   std::swap (original_subreg_reg_mode[nop], original_subreg_reg_mode[nop + 1]);
3938   std::swap (*curr_id->operand_loc[nop], *curr_id->operand_loc[nop + 1]);
3939   std::swap (equiv_substition_p[nop], equiv_substition_p[nop + 1]);
3940   /* Swap the duplicates too.  */
3941   lra_update_dup (curr_id, nop);
3942   lra_update_dup (curr_id, nop + 1);
3943 }
3944 
3945 /* Main entry point of the constraint code: search the body of the
3946    current insn to choose the best alternative.  It is mimicking insn
3947    alternative cost calculation model of former reload pass.  That is
3948    because machine descriptions were written to use this model.  This
3949    model can be changed in future.  Make commutative operand exchange
3950    if it is chosen.
3951 
3952    if CHECK_ONLY_P is false, do RTL changes to satisfy the
3953    constraints.  Return true if any change happened during function
3954    call.
3955 
3956    If CHECK_ONLY_P is true then don't do any transformation.  Just
3957    check that the insn satisfies all constraints.  If the insn does
3958    not satisfy any constraint, return true.  */
3959 static bool
curr_insn_transform(bool check_only_p)3960 curr_insn_transform (bool check_only_p)
3961 {
3962   int i, j, k;
3963   int n_operands;
3964   int n_alternatives;
3965   int n_outputs;
3966   int commutative;
3967   signed char goal_alt_matched[MAX_RECOG_OPERANDS][MAX_RECOG_OPERANDS];
3968   signed char match_inputs[MAX_RECOG_OPERANDS + 1];
3969   signed char outputs[MAX_RECOG_OPERANDS + 1];
3970   rtx_insn *before, *after;
3971   bool alt_p = false;
3972   /* Flag that the insn has been changed through a transformation.  */
3973   bool change_p;
3974   bool sec_mem_p;
3975   bool use_sec_mem_p;
3976   int max_regno_before;
3977   int reused_alternative_num;
3978 
3979   curr_insn_set = single_set (curr_insn);
3980   if (curr_insn_set != NULL_RTX && simple_move_p ())
3981     {
3982       /* We assume that the corresponding insn alternative has no
3983 	 earlier clobbers.  If it is not the case, don't define move
3984 	 cost equal to 2 for the corresponding register classes.  */
3985       lra_set_used_insn_alternative (curr_insn, LRA_NON_CLOBBERED_ALT);
3986       return false;
3987     }
3988 
3989   no_input_reloads_p = no_output_reloads_p = false;
3990   goal_alt_number = -1;
3991   change_p = sec_mem_p = false;
3992   /* CALL_INSNs are not allowed to have any output reloads; neither
3993      are insns that SET cc0.  Insns that use CC0 are not allowed to
3994      have any input reloads.  */
3995   if (CALL_P (curr_insn))
3996     no_output_reloads_p = true;
3997 
3998   if (HAVE_cc0 && reg_referenced_p (cc0_rtx, PATTERN (curr_insn)))
3999     no_input_reloads_p = true;
4000   if (HAVE_cc0 && reg_set_p (cc0_rtx, PATTERN (curr_insn)))
4001     no_output_reloads_p = true;
4002 
4003   n_operands = curr_static_id->n_operands;
4004   n_alternatives = curr_static_id->n_alternatives;
4005 
4006   /* Just return "no reloads" if insn has no operands with
4007      constraints.  */
4008   if (n_operands == 0 || n_alternatives == 0)
4009     return false;
4010 
4011   max_regno_before = max_reg_num ();
4012 
4013   for (i = 0; i < n_operands; i++)
4014     {
4015       goal_alt_matched[i][0] = -1;
4016       goal_alt_matches[i] = -1;
4017     }
4018 
4019   commutative = curr_static_id->commutative;
4020 
4021   /* Now see what we need for pseudos that didn't get hard regs or got
4022      the wrong kind of hard reg.  For this, we must consider all the
4023      operands together against the register constraints.  */
4024 
4025   best_losers = best_overall = INT_MAX;
4026   best_reload_sum = 0;
4027 
4028   curr_swapped = false;
4029   goal_alt_swapped = false;
4030 
4031   if (! check_only_p)
4032     /* Make equivalence substitution and memory subreg elimination
4033        before address processing because an address legitimacy can
4034        depend on memory mode.  */
4035     for (i = 0; i < n_operands; i++)
4036       {
4037 	rtx op, subst, old;
4038 	bool op_change_p = false;
4039 
4040 	if (curr_static_id->operand[i].is_operator)
4041 	  continue;
4042 
4043 	old = op = *curr_id->operand_loc[i];
4044 	if (GET_CODE (old) == SUBREG)
4045 	  old = SUBREG_REG (old);
4046 	subst = get_equiv_with_elimination (old, curr_insn);
4047 	original_subreg_reg_mode[i] = VOIDmode;
4048 	equiv_substition_p[i] = false;
4049 	if (subst != old)
4050 	  {
4051 	    equiv_substition_p[i] = true;
4052 	    subst = copy_rtx (subst);
4053 	    lra_assert (REG_P (old));
4054 	    if (GET_CODE (op) != SUBREG)
4055 	      *curr_id->operand_loc[i] = subst;
4056 	    else
4057 	      {
4058 		SUBREG_REG (op) = subst;
4059 		if (GET_MODE (subst) == VOIDmode)
4060 		  original_subreg_reg_mode[i] = GET_MODE (old);
4061 	      }
4062 	    if (lra_dump_file != NULL)
4063 	      {
4064 		fprintf (lra_dump_file,
4065 			 "Changing pseudo %d in operand %i of insn %u on equiv ",
4066 			 REGNO (old), i, INSN_UID (curr_insn));
4067 		dump_value_slim (lra_dump_file, subst, 1);
4068 		fprintf (lra_dump_file, "\n");
4069 	      }
4070 	    op_change_p = change_p = true;
4071 	  }
4072 	if (simplify_operand_subreg (i, GET_MODE (old)) || op_change_p)
4073 	  {
4074 	    change_p = true;
4075 	    lra_update_dup (curr_id, i);
4076 	  }
4077       }
4078 
4079   /* Reload address registers and displacements.  We do it before
4080      finding an alternative because of memory constraints.  */
4081   before = after = NULL;
4082   for (i = 0; i < n_operands; i++)
4083     if (! curr_static_id->operand[i].is_operator
4084 	&& process_address (i, check_only_p, &before, &after))
4085       {
4086 	if (check_only_p)
4087 	  return true;
4088 	change_p = true;
4089 	lra_update_dup (curr_id, i);
4090       }
4091 
4092   if (change_p)
4093     /* If we've changed the instruction then any alternative that
4094        we chose previously may no longer be valid.  */
4095     lra_set_used_insn_alternative (curr_insn, LRA_UNKNOWN_ALT);
4096 
4097   if (! check_only_p && curr_insn_set != NULL_RTX
4098       && check_and_process_move (&change_p, &sec_mem_p))
4099     return change_p;
4100 
4101  try_swapped:
4102 
4103   reused_alternative_num = check_only_p ? LRA_UNKNOWN_ALT : curr_id->used_insn_alternative;
4104   if (lra_dump_file != NULL && reused_alternative_num >= 0)
4105     fprintf (lra_dump_file, "Reusing alternative %d for insn #%u\n",
4106 	     reused_alternative_num, INSN_UID (curr_insn));
4107 
4108   if (process_alt_operands (reused_alternative_num))
4109     alt_p = true;
4110 
4111   if (check_only_p)
4112     return ! alt_p || best_losers != 0;
4113 
4114   /* If insn is commutative (it's safe to exchange a certain pair of
4115      operands) then we need to try each alternative twice, the second
4116      time matching those two operands as if we had exchanged them.  To
4117      do this, really exchange them in operands.
4118 
4119      If we have just tried the alternatives the second time, return
4120      operands to normal and drop through.  */
4121 
4122   if (reused_alternative_num < 0 && commutative >= 0)
4123     {
4124       curr_swapped = !curr_swapped;
4125       if (curr_swapped)
4126 	{
4127 	  swap_operands (commutative);
4128 	  goto try_swapped;
4129 	}
4130       else
4131 	swap_operands (commutative);
4132     }
4133 
4134   if (! alt_p && ! sec_mem_p)
4135     {
4136       /* No alternative works with reloads??  */
4137       if (INSN_CODE (curr_insn) >= 0)
4138 	fatal_insn ("unable to generate reloads for:", curr_insn);
4139       error_for_asm (curr_insn,
4140 		     "inconsistent operand constraints in an %<asm%>");
4141       lra_asm_error_p = true;
4142       if (! JUMP_P (curr_insn))
4143 	{
4144 	  /* Avoid further trouble with this insn.  Don't generate use
4145 	     pattern here as we could use the insn SP offset.  */
4146 	  lra_set_insn_deleted (curr_insn);
4147 	}
4148       else
4149 	{
4150 	  lra_invalidate_insn_data (curr_insn);
4151 	  ira_nullify_asm_goto (curr_insn);
4152 	  lra_update_insn_regno_info (curr_insn);
4153 	}
4154       return true;
4155     }
4156 
4157   /* If the best alternative is with operands 1 and 2 swapped, swap
4158      them.  Update the operand numbers of any reloads already
4159      pushed.  */
4160 
4161   if (goal_alt_swapped)
4162     {
4163       if (lra_dump_file != NULL)
4164 	fprintf (lra_dump_file, "  Commutative operand exchange in insn %u\n",
4165 		 INSN_UID (curr_insn));
4166 
4167       /* Swap the duplicates too.  */
4168       swap_operands (commutative);
4169       change_p = true;
4170     }
4171 
4172   /* Some targets' TARGET_SECONDARY_MEMORY_NEEDED (e.g. x86) are defined
4173      too conservatively.  So we use the secondary memory only if there
4174      is no any alternative without reloads.  */
4175   use_sec_mem_p = false;
4176   if (! alt_p)
4177     use_sec_mem_p = true;
4178   else if (sec_mem_p)
4179     {
4180       for (i = 0; i < n_operands; i++)
4181 	if (! goal_alt_win[i] && ! goal_alt_match_win[i])
4182 	  break;
4183       use_sec_mem_p = i < n_operands;
4184     }
4185 
4186   if (use_sec_mem_p)
4187     {
4188       int in = -1, out = -1;
4189       rtx new_reg, src, dest, rld;
4190       machine_mode sec_mode, rld_mode;
4191 
4192       lra_assert (curr_insn_set != NULL_RTX && sec_mem_p);
4193       dest = SET_DEST (curr_insn_set);
4194       src = SET_SRC (curr_insn_set);
4195       for (i = 0; i < n_operands; i++)
4196 	if (*curr_id->operand_loc[i] == dest)
4197 	  out = i;
4198 	else if (*curr_id->operand_loc[i] == src)
4199 	  in = i;
4200       for (i = 0; i < curr_static_id->n_dups; i++)
4201 	if (out < 0 && *curr_id->dup_loc[i] == dest)
4202 	  out = curr_static_id->dup_num[i];
4203 	else if (in < 0 && *curr_id->dup_loc[i] == src)
4204 	  in = curr_static_id->dup_num[i];
4205       lra_assert (out >= 0 && in >= 0
4206 		  && curr_static_id->operand[out].type == OP_OUT
4207 		  && curr_static_id->operand[in].type == OP_IN);
4208       rld = partial_subreg_p (GET_MODE (src), GET_MODE (dest)) ? src : dest;
4209       rld_mode = GET_MODE (rld);
4210       sec_mode = targetm.secondary_memory_needed_mode (rld_mode);
4211       new_reg = lra_create_new_reg (sec_mode, NULL_RTX,
4212 				    NO_REGS, "secondary");
4213       /* If the mode is changed, it should be wider.  */
4214       lra_assert (!partial_subreg_p (sec_mode, rld_mode));
4215       if (sec_mode != rld_mode)
4216         {
4217 	  /* If the target says specifically to use another mode for
4218 	     secondary memory moves we cannot reuse the original
4219 	     insn.  */
4220 	  after = emit_spill_move (false, new_reg, dest);
4221 	  lra_process_new_insns (curr_insn, NULL, after,
4222 				 "Inserting the sec. move");
4223 	  /* We may have non null BEFORE here (e.g. after address
4224 	     processing.  */
4225 	  push_to_sequence (before);
4226 	  before = emit_spill_move (true, new_reg, src);
4227 	  emit_insn (before);
4228 	  before = get_insns ();
4229 	  end_sequence ();
4230 	  lra_process_new_insns (curr_insn, before, NULL, "Changing on");
4231 	  lra_set_insn_deleted (curr_insn);
4232 	}
4233       else if (dest == rld)
4234         {
4235 	  *curr_id->operand_loc[out] = new_reg;
4236 	  lra_update_dup (curr_id, out);
4237 	  after = emit_spill_move (false, new_reg, dest);
4238 	  lra_process_new_insns (curr_insn, NULL, after,
4239 				 "Inserting the sec. move");
4240 	}
4241       else
4242 	{
4243 	  *curr_id->operand_loc[in] = new_reg;
4244 	  lra_update_dup (curr_id, in);
4245 	  /* See comments above.  */
4246 	  push_to_sequence (before);
4247 	  before = emit_spill_move (true, new_reg, src);
4248 	  emit_insn (before);
4249 	  before = get_insns ();
4250 	  end_sequence ();
4251 	  lra_process_new_insns (curr_insn, before, NULL,
4252 				 "Inserting the sec. move");
4253 	}
4254       lra_update_insn_regno_info (curr_insn);
4255       return true;
4256     }
4257 
4258   lra_assert (goal_alt_number >= 0);
4259   lra_set_used_insn_alternative (curr_insn, goal_alt_number);
4260 
4261   if (lra_dump_file != NULL)
4262     {
4263       const char *p;
4264 
4265       fprintf (lra_dump_file, "	 Choosing alt %d in insn %u:",
4266 	       goal_alt_number, INSN_UID (curr_insn));
4267       for (i = 0; i < n_operands; i++)
4268 	{
4269 	  p = (curr_static_id->operand_alternative
4270 	       [goal_alt_number * n_operands + i].constraint);
4271 	  if (*p == '\0')
4272 	    continue;
4273 	  fprintf (lra_dump_file, "  (%d) ", i);
4274 	  for (; *p != '\0' && *p != ',' && *p != '#'; p++)
4275 	    fputc (*p, lra_dump_file);
4276 	}
4277       if (INSN_CODE (curr_insn) >= 0
4278           && (p = get_insn_name (INSN_CODE (curr_insn))) != NULL)
4279         fprintf (lra_dump_file, " {%s}", p);
4280       if (maybe_ne (curr_id->sp_offset, 0))
4281 	{
4282 	  fprintf (lra_dump_file, " (sp_off=");
4283 	  print_dec (curr_id->sp_offset, lra_dump_file);
4284 	  fprintf (lra_dump_file, ")");
4285 	}
4286       fprintf (lra_dump_file, "\n");
4287     }
4288 
4289   /* Right now, for any pair of operands I and J that are required to
4290      match, with J < I, goal_alt_matches[I] is J.  Add I to
4291      goal_alt_matched[J].  */
4292 
4293   for (i = 0; i < n_operands; i++)
4294     if ((j = goal_alt_matches[i]) >= 0)
4295       {
4296 	for (k = 0; goal_alt_matched[j][k] >= 0; k++)
4297 	  ;
4298 	/* We allow matching one output operand and several input
4299 	   operands.  */
4300 	lra_assert (k == 0
4301 		    || (curr_static_id->operand[j].type == OP_OUT
4302 			&& curr_static_id->operand[i].type == OP_IN
4303 			&& (curr_static_id->operand
4304 			    [goal_alt_matched[j][0]].type == OP_IN)));
4305 	goal_alt_matched[j][k] = i;
4306 	goal_alt_matched[j][k + 1] = -1;
4307       }
4308 
4309   for (i = 0; i < n_operands; i++)
4310     goal_alt_win[i] |= goal_alt_match_win[i];
4311 
4312   /* Any constants that aren't allowed and can't be reloaded into
4313      registers are here changed into memory references.	 */
4314   for (i = 0; i < n_operands; i++)
4315     if (goal_alt_win[i])
4316       {
4317 	int regno;
4318 	enum reg_class new_class;
4319 	rtx reg = *curr_id->operand_loc[i];
4320 
4321 	if (GET_CODE (reg) == SUBREG)
4322 	  reg = SUBREG_REG (reg);
4323 
4324 	if (REG_P (reg) && (regno = REGNO (reg)) >= FIRST_PSEUDO_REGISTER)
4325 	  {
4326 	    bool ok_p = in_class_p (reg, goal_alt[i], &new_class);
4327 
4328 	    if (new_class != NO_REGS && get_reg_class (regno) != new_class)
4329 	      {
4330 		lra_assert (ok_p);
4331 		lra_change_class (regno, new_class, "      Change to", true);
4332 	      }
4333 	  }
4334       }
4335     else
4336       {
4337 	const char *constraint;
4338 	char c;
4339 	rtx op = *curr_id->operand_loc[i];
4340 	rtx subreg = NULL_RTX;
4341 	machine_mode mode = curr_operand_mode[i];
4342 
4343 	if (GET_CODE (op) == SUBREG)
4344 	  {
4345 	    subreg = op;
4346 	    op = SUBREG_REG (op);
4347 	    mode = GET_MODE (op);
4348 	  }
4349 
4350 	if (CONST_POOL_OK_P (mode, op)
4351 	    && ((targetm.preferred_reload_class
4352 		 (op, (enum reg_class) goal_alt[i]) == NO_REGS)
4353 		|| no_input_reloads_p))
4354 	  {
4355 	    rtx tem = force_const_mem (mode, op);
4356 
4357 	    change_p = true;
4358 	    if (subreg != NULL_RTX)
4359 	      tem = gen_rtx_SUBREG (mode, tem, SUBREG_BYTE (subreg));
4360 
4361 	    *curr_id->operand_loc[i] = tem;
4362 	    lra_update_dup (curr_id, i);
4363 	    process_address (i, false, &before, &after);
4364 
4365 	    /* If the alternative accepts constant pool refs directly
4366 	       there will be no reload needed at all.  */
4367 	    if (subreg != NULL_RTX)
4368 	      continue;
4369 	    /* Skip alternatives before the one requested.  */
4370 	    constraint = (curr_static_id->operand_alternative
4371 			  [goal_alt_number * n_operands + i].constraint);
4372 	    for (;
4373 		 (c = *constraint) && c != ',' && c != '#';
4374 		 constraint += CONSTRAINT_LEN (c, constraint))
4375 	      {
4376 		enum constraint_num cn = lookup_constraint (constraint);
4377 		if ((insn_extra_memory_constraint (cn)
4378 		     || insn_extra_special_memory_constraint (cn)
4379 		     || insn_extra_relaxed_memory_constraint (cn))
4380 		    && satisfies_memory_constraint_p (tem, cn))
4381 		  break;
4382 	      }
4383 	    if (c == '\0' || c == ',' || c == '#')
4384 	      continue;
4385 
4386 	    goal_alt_win[i] = true;
4387 	  }
4388       }
4389 
4390   n_outputs = 0;
4391   outputs[0] = -1;
4392   for (i = 0; i < n_operands; i++)
4393     {
4394       int regno;
4395       bool optional_p = false;
4396       rtx old, new_reg;
4397       rtx op = *curr_id->operand_loc[i];
4398 
4399       if (goal_alt_win[i])
4400 	{
4401 	  if (goal_alt[i] == NO_REGS
4402 	      && REG_P (op)
4403 	      /* When we assign NO_REGS it means that we will not
4404 		 assign a hard register to the scratch pseudo by
4405 		 assigment pass and the scratch pseudo will be
4406 		 spilled.  Spilled scratch pseudos are transformed
4407 		 back to scratches at the LRA end.  */
4408 	      && ira_former_scratch_operand_p (curr_insn, i)
4409 	      && ira_former_scratch_p (REGNO (op)))
4410 	    {
4411 	      int regno = REGNO (op);
4412 	      lra_change_class (regno, NO_REGS, "      Change to", true);
4413 	      if (lra_get_regno_hard_regno (regno) >= 0)
4414 		/* We don't have to mark all insn affected by the
4415 		   spilled pseudo as there is only one such insn, the
4416 		   current one.  */
4417 		reg_renumber[regno] = -1;
4418 	      lra_assert (bitmap_single_bit_set_p
4419 			  (&lra_reg_info[REGNO (op)].insn_bitmap));
4420 	    }
4421 	  /* We can do an optional reload.  If the pseudo got a hard
4422 	     reg, we might improve the code through inheritance.  If
4423 	     it does not get a hard register we coalesce memory/memory
4424 	     moves later.  Ignore move insns to avoid cycling.  */
4425 	  if (! lra_simple_p
4426 	      && lra_undo_inheritance_iter < LRA_MAX_INHERITANCE_PASSES
4427 	      && goal_alt[i] != NO_REGS && REG_P (op)
4428 	      && (regno = REGNO (op)) >= FIRST_PSEUDO_REGISTER
4429 	      && regno < new_regno_start
4430 	      && ! ira_former_scratch_p (regno)
4431 	      && reg_renumber[regno] < 0
4432 	      /* Check that the optional reload pseudo will be able to
4433 		 hold given mode value.  */
4434 	      && ! (prohibited_class_reg_set_mode_p
4435 		    (goal_alt[i], reg_class_contents[goal_alt[i]],
4436 		     PSEUDO_REGNO_MODE (regno)))
4437 	      && (curr_insn_set == NULL_RTX
4438 		  || !((REG_P (SET_SRC (curr_insn_set))
4439 			|| MEM_P (SET_SRC (curr_insn_set))
4440 			|| GET_CODE (SET_SRC (curr_insn_set)) == SUBREG)
4441 		       && (REG_P (SET_DEST (curr_insn_set))
4442 			   || MEM_P (SET_DEST (curr_insn_set))
4443 			   || GET_CODE (SET_DEST (curr_insn_set)) == SUBREG))))
4444 	    optional_p = true;
4445 	  else if (goal_alt_matched[i][0] != -1
4446 		   && curr_static_id->operand[i].type == OP_OUT
4447 		   && (curr_static_id->operand_alternative
4448 		       [goal_alt_number * n_operands + i].earlyclobber)
4449 		   && REG_P (op))
4450 	    {
4451 	      for (j = 0; goal_alt_matched[i][j] != -1; j++)
4452 		{
4453 		  rtx op2 = *curr_id->operand_loc[goal_alt_matched[i][j]];
4454 
4455 		  if (REG_P (op2) && REGNO (op) != REGNO (op2))
4456 		    break;
4457 		}
4458 	      if (goal_alt_matched[i][j] != -1)
4459 		{
4460 		  /* Generate reloads for different output and matched
4461 		     input registers.  This is the easiest way to avoid
4462 		     creation of non-existing register conflicts in
4463 		     lra-lives.c.  */
4464 		  match_reload (i, goal_alt_matched[i], outputs, goal_alt[i], &before,
4465 				&after, TRUE);
4466 		  outputs[n_outputs++] = i;
4467 		  outputs[n_outputs] = -1;
4468 		}
4469 	      continue;
4470 	    }
4471 	  else
4472 	    continue;
4473 	}
4474 
4475       /* Operands that match previous ones have already been handled.  */
4476       if (goal_alt_matches[i] >= 0)
4477 	continue;
4478 
4479       /* We should not have an operand with a non-offsettable address
4480 	 appearing where an offsettable address will do.  It also may
4481 	 be a case when the address should be special in other words
4482 	 not a general one (e.g. it needs no index reg).  */
4483       if (goal_alt_matched[i][0] == -1 && goal_alt_offmemok[i] && MEM_P (op))
4484 	{
4485 	  enum reg_class rclass;
4486 	  rtx *loc = &XEXP (op, 0);
4487 	  enum rtx_code code = GET_CODE (*loc);
4488 
4489 	  push_to_sequence (before);
4490 	  rclass = base_reg_class (GET_MODE (op), MEM_ADDR_SPACE (op),
4491 				   MEM, SCRATCH);
4492 	  if (GET_RTX_CLASS (code) == RTX_AUTOINC)
4493 	    new_reg = emit_inc (rclass, *loc, *loc,
4494 				/* This value does not matter for MODIFY.  */
4495 				GET_MODE_SIZE (GET_MODE (op)));
4496 	  else if (get_reload_reg (OP_IN, Pmode, *loc, rclass, FALSE,
4497 				   "offsetable address", &new_reg))
4498 	    {
4499 	      rtx addr = *loc;
4500 	      enum rtx_code code = GET_CODE (addr);
4501 	      bool align_p = false;
4502 
4503 	      if (code == AND && CONST_INT_P (XEXP (addr, 1)))
4504 		{
4505 		  /* (and ... (const_int -X)) is used to align to X bytes.  */
4506 		  align_p = true;
4507 		  addr = XEXP (*loc, 0);
4508 		}
4509 	      else
4510 		addr = canonicalize_reload_addr (addr);
4511 
4512 	      lra_emit_move (new_reg, addr);
4513 	      if (align_p)
4514 		emit_move_insn (new_reg, gen_rtx_AND (GET_MODE (new_reg), new_reg, XEXP (*loc, 1)));
4515 	    }
4516 	  before = get_insns ();
4517 	  end_sequence ();
4518 	  *loc = new_reg;
4519 	  lra_update_dup (curr_id, i);
4520 	}
4521       else if (goal_alt_matched[i][0] == -1)
4522 	{
4523 	  machine_mode mode;
4524 	  rtx reg, *loc;
4525 	  int hard_regno;
4526 	  enum op_type type = curr_static_id->operand[i].type;
4527 
4528 	  loc = curr_id->operand_loc[i];
4529 	  mode = curr_operand_mode[i];
4530 	  if (GET_CODE (*loc) == SUBREG)
4531 	    {
4532 	      reg = SUBREG_REG (*loc);
4533 	      poly_int64 byte = SUBREG_BYTE (*loc);
4534 	      if (REG_P (reg)
4535 		  /* Strict_low_part requires reloading the register and not
4536 		     just the subreg.  Likewise for a strict subreg no wider
4537 		     than a word for WORD_REGISTER_OPERATIONS targets.  */
4538 		  && (curr_static_id->operand[i].strict_low
4539 		      || (!paradoxical_subreg_p (mode, GET_MODE (reg))
4540 			  && (hard_regno
4541 			      = get_try_hard_regno (REGNO (reg))) >= 0
4542 			  && (simplify_subreg_regno
4543 			      (hard_regno,
4544 			       GET_MODE (reg), byte, mode) < 0)
4545 			  && (goal_alt[i] == NO_REGS
4546 			      || (simplify_subreg_regno
4547 				  (ira_class_hard_regs[goal_alt[i]][0],
4548 				   GET_MODE (reg), byte, mode) >= 0)))
4549 		      || (partial_subreg_p (mode, GET_MODE (reg))
4550 			  && known_le (GET_MODE_SIZE (GET_MODE (reg)),
4551 				       UNITS_PER_WORD)
4552 			  && WORD_REGISTER_OPERATIONS)))
4553 		{
4554 		  /* An OP_INOUT is required when reloading a subreg of a
4555 		     mode wider than a word to ensure that data beyond the
4556 		     word being reloaded is preserved.  Also automatically
4557 		     ensure that strict_low_part reloads are made into
4558 		     OP_INOUT which should already be true from the backend
4559 		     constraints.  */
4560 		  if (type == OP_OUT
4561 		      && (curr_static_id->operand[i].strict_low
4562 			  || read_modify_subreg_p (*loc)))
4563 		    type = OP_INOUT;
4564 		  loc = &SUBREG_REG (*loc);
4565 		  mode = GET_MODE (*loc);
4566 		}
4567 	    }
4568 	  old = *loc;
4569 	  if (get_reload_reg (type, mode, old, goal_alt[i],
4570 			      loc != curr_id->operand_loc[i], "", &new_reg)
4571 	      && type != OP_OUT)
4572 	    {
4573 	      push_to_sequence (before);
4574 	      lra_emit_move (new_reg, old);
4575 	      before = get_insns ();
4576 	      end_sequence ();
4577 	    }
4578 	  *loc = new_reg;
4579 	  if (type != OP_IN
4580 	      && find_reg_note (curr_insn, REG_UNUSED, old) == NULL_RTX)
4581 	    {
4582 	      start_sequence ();
4583 	      lra_emit_move (type == OP_INOUT ? copy_rtx (old) : old, new_reg);
4584 	      emit_insn (after);
4585 	      after = get_insns ();
4586 	      end_sequence ();
4587 	      *loc = new_reg;
4588 	    }
4589 	  for (j = 0; j < goal_alt_dont_inherit_ops_num; j++)
4590 	    if (goal_alt_dont_inherit_ops[j] == i)
4591 	      {
4592 		lra_set_regno_unique_value (REGNO (new_reg));
4593 		break;
4594 	      }
4595 	  lra_update_dup (curr_id, i);
4596 	}
4597       else if (curr_static_id->operand[i].type == OP_IN
4598 	       && (curr_static_id->operand[goal_alt_matched[i][0]].type
4599 		   == OP_OUT
4600 		   || (curr_static_id->operand[goal_alt_matched[i][0]].type
4601 		       == OP_INOUT
4602 		       && (operands_match_p
4603 			   (*curr_id->operand_loc[i],
4604 			    *curr_id->operand_loc[goal_alt_matched[i][0]],
4605 			    -1)))))
4606 	{
4607 	  /* generate reloads for input and matched outputs.  */
4608 	  match_inputs[0] = i;
4609 	  match_inputs[1] = -1;
4610 	  match_reload (goal_alt_matched[i][0], match_inputs, outputs,
4611 			goal_alt[i], &before, &after,
4612 			curr_static_id->operand_alternative
4613 			[goal_alt_number * n_operands + goal_alt_matched[i][0]]
4614 			.earlyclobber);
4615 	}
4616       else if ((curr_static_id->operand[i].type == OP_OUT
4617 		|| (curr_static_id->operand[i].type == OP_INOUT
4618 		    && (operands_match_p
4619 			(*curr_id->operand_loc[i],
4620 			 *curr_id->operand_loc[goal_alt_matched[i][0]],
4621 			 -1))))
4622 	       && (curr_static_id->operand[goal_alt_matched[i][0]].type
4623 		    == OP_IN))
4624 	/* Generate reloads for output and matched inputs.  */
4625 	match_reload (i, goal_alt_matched[i], outputs, goal_alt[i], &before,
4626 		      &after, curr_static_id->operand_alternative
4627 			      [goal_alt_number * n_operands + i].earlyclobber);
4628       else if (curr_static_id->operand[i].type == OP_IN
4629 	       && (curr_static_id->operand[goal_alt_matched[i][0]].type
4630 		   == OP_IN))
4631 	{
4632 	  /* Generate reloads for matched inputs.  */
4633 	  match_inputs[0] = i;
4634 	  for (j = 0; (k = goal_alt_matched[i][j]) >= 0; j++)
4635 	    match_inputs[j + 1] = k;
4636 	  match_inputs[j + 1] = -1;
4637 	  match_reload (-1, match_inputs, outputs, goal_alt[i], &before,
4638 			&after, false);
4639 	}
4640       else
4641 	/* We must generate code in any case when function
4642 	   process_alt_operands decides that it is possible.  */
4643 	gcc_unreachable ();
4644 
4645       /* Memorise processed outputs so that output remaining to be processed
4646 	 can avoid using the same register value (see match_reload).  */
4647       if (curr_static_id->operand[i].type == OP_OUT)
4648 	{
4649 	  outputs[n_outputs++] = i;
4650 	  outputs[n_outputs] = -1;
4651 	}
4652 
4653       if (optional_p)
4654 	{
4655 	  rtx reg = op;
4656 
4657 	  lra_assert (REG_P (reg));
4658 	  regno = REGNO (reg);
4659 	  op = *curr_id->operand_loc[i]; /* Substitution.  */
4660 	  if (GET_CODE (op) == SUBREG)
4661 	    op = SUBREG_REG (op);
4662 	  gcc_assert (REG_P (op) && (int) REGNO (op) >= new_regno_start);
4663 	  bitmap_set_bit (&lra_optional_reload_pseudos, REGNO (op));
4664 	  lra_reg_info[REGNO (op)].restore_rtx = reg;
4665 	  if (lra_dump_file != NULL)
4666 	    fprintf (lra_dump_file,
4667 		     "      Making reload reg %d for reg %d optional\n",
4668 		     REGNO (op), regno);
4669 	}
4670     }
4671   if (before != NULL_RTX || after != NULL_RTX
4672       || max_regno_before != max_reg_num ())
4673     change_p = true;
4674   if (change_p)
4675     {
4676       lra_update_operator_dups (curr_id);
4677       /* Something changes -- process the insn.	 */
4678       lra_update_insn_regno_info (curr_insn);
4679     }
4680   lra_process_new_insns (curr_insn, before, after, "Inserting insn reload");
4681   return change_p;
4682 }
4683 
4684 /* Return true if INSN satisfies all constraints.  In other words, no
4685    reload insns are needed.  */
4686 bool
lra_constrain_insn(rtx_insn * insn)4687 lra_constrain_insn (rtx_insn *insn)
4688 {
4689   int saved_new_regno_start = new_regno_start;
4690   int saved_new_insn_uid_start = new_insn_uid_start;
4691   bool change_p;
4692 
4693   curr_insn = insn;
4694   curr_id = lra_get_insn_recog_data (curr_insn);
4695   curr_static_id = curr_id->insn_static_data;
4696   new_insn_uid_start = get_max_uid ();
4697   new_regno_start = max_reg_num ();
4698   change_p = curr_insn_transform (true);
4699   new_regno_start = saved_new_regno_start;
4700   new_insn_uid_start = saved_new_insn_uid_start;
4701   return ! change_p;
4702 }
4703 
4704 /* Return true if X is in LIST.	 */
4705 static bool
in_list_p(rtx x,rtx list)4706 in_list_p (rtx x, rtx list)
4707 {
4708   for (; list != NULL_RTX; list = XEXP (list, 1))
4709     if (XEXP (list, 0) == x)
4710       return true;
4711   return false;
4712 }
4713 
4714 /* Return true if X contains an allocatable hard register (if
4715    HARD_REG_P) or a (spilled if SPILLED_P) pseudo.  */
4716 static bool
contains_reg_p(rtx x,bool hard_reg_p,bool spilled_p)4717 contains_reg_p (rtx x, bool hard_reg_p, bool spilled_p)
4718 {
4719   int i, j;
4720   const char *fmt;
4721   enum rtx_code code;
4722 
4723   code = GET_CODE (x);
4724   if (REG_P (x))
4725     {
4726       int regno = REGNO (x);
4727       HARD_REG_SET alloc_regs;
4728 
4729       if (hard_reg_p)
4730 	{
4731 	  if (regno >= FIRST_PSEUDO_REGISTER)
4732 	    regno = lra_get_regno_hard_regno (regno);
4733 	  if (regno < 0)
4734 	    return false;
4735 	  alloc_regs = ~lra_no_alloc_regs;
4736 	  return overlaps_hard_reg_set_p (alloc_regs, GET_MODE (x), regno);
4737 	}
4738       else
4739 	{
4740 	  if (regno < FIRST_PSEUDO_REGISTER)
4741 	    return false;
4742 	  if (! spilled_p)
4743 	    return true;
4744 	  return lra_get_regno_hard_regno (regno) < 0;
4745 	}
4746     }
4747   fmt = GET_RTX_FORMAT (code);
4748   for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
4749     {
4750       if (fmt[i] == 'e')
4751 	{
4752 	  if (contains_reg_p (XEXP (x, i), hard_reg_p, spilled_p))
4753 	    return true;
4754 	}
4755       else if (fmt[i] == 'E')
4756 	{
4757 	  for (j = XVECLEN (x, i) - 1; j >= 0; j--)
4758 	    if (contains_reg_p (XVECEXP (x, i, j), hard_reg_p, spilled_p))
4759 	      return true;
4760 	}
4761     }
4762   return false;
4763 }
4764 
4765 /* Process all regs in location *LOC and change them on equivalent
4766    substitution.  Return true if any change was done.  */
4767 static bool
loc_equivalence_change_p(rtx * loc)4768 loc_equivalence_change_p (rtx *loc)
4769 {
4770   rtx subst, reg, x = *loc;
4771   bool result = false;
4772   enum rtx_code code = GET_CODE (x);
4773   const char *fmt;
4774   int i, j;
4775 
4776   if (code == SUBREG)
4777     {
4778       reg = SUBREG_REG (x);
4779       if ((subst = get_equiv_with_elimination (reg, curr_insn)) != reg
4780 	  && GET_MODE (subst) == VOIDmode)
4781 	{
4782 	  /* We cannot reload debug location.  Simplify subreg here
4783 	     while we know the inner mode.  */
4784 	  *loc = simplify_gen_subreg (GET_MODE (x), subst,
4785 				      GET_MODE (reg), SUBREG_BYTE (x));
4786 	  return true;
4787 	}
4788     }
4789   if (code == REG && (subst = get_equiv_with_elimination (x, curr_insn)) != x)
4790     {
4791       *loc = subst;
4792       return true;
4793     }
4794 
4795   /* Scan all the operand sub-expressions.  */
4796   fmt = GET_RTX_FORMAT (code);
4797   for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
4798     {
4799       if (fmt[i] == 'e')
4800 	result = loc_equivalence_change_p (&XEXP (x, i)) || result;
4801       else if (fmt[i] == 'E')
4802 	for (j = XVECLEN (x, i) - 1; j >= 0; j--)
4803 	  result
4804 	    = loc_equivalence_change_p (&XVECEXP (x, i, j)) || result;
4805     }
4806   return result;
4807 }
4808 
4809 /* Similar to loc_equivalence_change_p, but for use as
4810    simplify_replace_fn_rtx callback.  DATA is insn for which the
4811    elimination is done.  If it null we don't do the elimination.  */
4812 static rtx
loc_equivalence_callback(rtx loc,const_rtx,void * data)4813 loc_equivalence_callback (rtx loc, const_rtx, void *data)
4814 {
4815   if (!REG_P (loc))
4816     return NULL_RTX;
4817 
4818   rtx subst = (data == NULL
4819 	       ? get_equiv (loc) : get_equiv_with_elimination (loc, (rtx_insn *) data));
4820   if (subst != loc)
4821     return subst;
4822 
4823   return NULL_RTX;
4824 }
4825 
4826 /* Maximum number of generated reload insns per an insn.  It is for
4827    preventing this pass cycling in a bug case.	*/
4828 #define MAX_RELOAD_INSNS_NUMBER LRA_MAX_INSN_RELOADS
4829 
4830 /* The current iteration number of this LRA pass.  */
4831 int lra_constraint_iter;
4832 
4833 /* True if we should during assignment sub-pass check assignment
4834    correctness for all pseudos and spill some of them to correct
4835    conflicts.  It can be necessary when we substitute equiv which
4836    needs checking register allocation correctness because the
4837    equivalent value contains allocatable hard registers, or when we
4838    restore multi-register pseudo, or when we change the insn code and
4839    its operand became INOUT operand when it was IN one before.  */
4840 bool check_and_force_assignment_correctness_p;
4841 
4842 /* Return true if REGNO is referenced in more than one block.  */
4843 static bool
multi_block_pseudo_p(int regno)4844 multi_block_pseudo_p (int regno)
4845 {
4846   basic_block bb = NULL;
4847   unsigned int uid;
4848   bitmap_iterator bi;
4849 
4850   if (regno < FIRST_PSEUDO_REGISTER)
4851     return false;
4852 
4853   EXECUTE_IF_SET_IN_BITMAP (&lra_reg_info[regno].insn_bitmap, 0, uid, bi)
4854     if (bb == NULL)
4855       bb = BLOCK_FOR_INSN (lra_insn_recog_data[uid]->insn);
4856     else if (BLOCK_FOR_INSN (lra_insn_recog_data[uid]->insn) != bb)
4857       return true;
4858   return false;
4859 }
4860 
4861 /* Return true if LIST contains a deleted insn.  */
4862 static bool
contains_deleted_insn_p(rtx_insn_list * list)4863 contains_deleted_insn_p (rtx_insn_list *list)
4864 {
4865   for (; list != NULL_RTX; list = list->next ())
4866     if (NOTE_P (list->insn ())
4867 	&& NOTE_KIND (list->insn ()) == NOTE_INSN_DELETED)
4868       return true;
4869   return false;
4870 }
4871 
4872 /* Return true if X contains a pseudo dying in INSN.  */
4873 static bool
dead_pseudo_p(rtx x,rtx_insn * insn)4874 dead_pseudo_p (rtx x, rtx_insn *insn)
4875 {
4876   int i, j;
4877   const char *fmt;
4878   enum rtx_code code;
4879 
4880   if (REG_P (x))
4881     return (insn != NULL_RTX
4882 	    && find_regno_note (insn, REG_DEAD, REGNO (x)) != NULL_RTX);
4883   code = GET_CODE (x);
4884   fmt = GET_RTX_FORMAT (code);
4885   for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
4886     {
4887       if (fmt[i] == 'e')
4888 	{
4889 	  if (dead_pseudo_p (XEXP (x, i), insn))
4890 	    return true;
4891 	}
4892       else if (fmt[i] == 'E')
4893 	{
4894 	  for (j = XVECLEN (x, i) - 1; j >= 0; j--)
4895 	    if (dead_pseudo_p (XVECEXP (x, i, j), insn))
4896 	      return true;
4897 	}
4898     }
4899   return false;
4900 }
4901 
4902 /* Return true if INSN contains a dying pseudo in INSN right hand
4903    side.  */
4904 static bool
insn_rhs_dead_pseudo_p(rtx_insn * insn)4905 insn_rhs_dead_pseudo_p (rtx_insn *insn)
4906 {
4907   rtx set = single_set (insn);
4908 
4909   gcc_assert (set != NULL);
4910   return dead_pseudo_p (SET_SRC (set), insn);
4911 }
4912 
4913 /* Return true if any init insn of REGNO contains a dying pseudo in
4914    insn right hand side.  */
4915 static bool
init_insn_rhs_dead_pseudo_p(int regno)4916 init_insn_rhs_dead_pseudo_p (int regno)
4917 {
4918   rtx_insn_list *insns = ira_reg_equiv[regno].init_insns;
4919 
4920   if (insns == NULL)
4921     return false;
4922   for (; insns != NULL_RTX; insns = insns->next ())
4923     if (insn_rhs_dead_pseudo_p (insns->insn ()))
4924       return true;
4925   return false;
4926 }
4927 
4928 /* Return TRUE if REGNO has a reverse equivalence.  The equivalence is
4929    reverse only if we have one init insn with given REGNO as a
4930    source.  */
4931 static bool
reverse_equiv_p(int regno)4932 reverse_equiv_p (int regno)
4933 {
4934   rtx_insn_list *insns = ira_reg_equiv[regno].init_insns;
4935   rtx set;
4936 
4937   if (insns == NULL)
4938     return false;
4939   if (! INSN_P (insns->insn ())
4940       || insns->next () != NULL)
4941     return false;
4942   if ((set = single_set (insns->insn ())) == NULL_RTX)
4943     return false;
4944   return REG_P (SET_SRC (set)) && (int) REGNO (SET_SRC (set)) == regno;
4945 }
4946 
4947 /* Return TRUE if REGNO was reloaded in an equivalence init insn.  We
4948    call this function only for non-reverse equivalence.  */
4949 static bool
contains_reloaded_insn_p(int regno)4950 contains_reloaded_insn_p (int regno)
4951 {
4952   rtx set;
4953   rtx_insn_list *list = ira_reg_equiv[regno].init_insns;
4954 
4955   for (; list != NULL; list = list->next ())
4956     if ((set = single_set (list->insn ())) == NULL_RTX
4957 	|| ! REG_P (SET_DEST (set))
4958 	|| (int) REGNO (SET_DEST (set)) != regno)
4959       return true;
4960   return false;
4961 }
4962 
4963 /* Entry function of LRA constraint pass.  Return true if the
4964    constraint pass did change the code.	 */
4965 bool
lra_constraints(bool first_p)4966 lra_constraints (bool first_p)
4967 {
4968   bool changed_p;
4969   int i, hard_regno, new_insns_num;
4970   unsigned int min_len, new_min_len, uid;
4971   rtx set, x, reg, dest_reg;
4972   basic_block last_bb;
4973   bitmap_iterator bi;
4974 
4975   lra_constraint_iter++;
4976   if (lra_dump_file != NULL)
4977     fprintf (lra_dump_file, "\n********** Local #%d: **********\n\n",
4978 	     lra_constraint_iter);
4979   changed_p = false;
4980   if (pic_offset_table_rtx
4981       && REGNO (pic_offset_table_rtx) >= FIRST_PSEUDO_REGISTER)
4982     check_and_force_assignment_correctness_p = true;
4983   else if (first_p)
4984     /* On the first iteration we should check IRA assignment
4985        correctness.  In rare cases, the assignments can be wrong as
4986        early clobbers operands are ignored in IRA or usages of
4987        paradoxical sub-registers are not taken into account by
4988        IRA.  */
4989     check_and_force_assignment_correctness_p = true;
4990   new_insn_uid_start = get_max_uid ();
4991   new_regno_start = first_p ? lra_constraint_new_regno_start : max_reg_num ();
4992   /* Mark used hard regs for target stack size calulations.  */
4993   for (i = FIRST_PSEUDO_REGISTER; i < new_regno_start; i++)
4994     if (lra_reg_info[i].nrefs != 0
4995 	&& (hard_regno = lra_get_regno_hard_regno (i)) >= 0)
4996       {
4997 	int j, nregs;
4998 
4999 	nregs = hard_regno_nregs (hard_regno, lra_reg_info[i].biggest_mode);
5000 	for (j = 0; j < nregs; j++)
5001 	  df_set_regs_ever_live (hard_regno + j, true);
5002       }
5003   /* Do elimination before the equivalence processing as we can spill
5004      some pseudos during elimination.  */
5005   lra_eliminate (false, first_p);
5006   auto_bitmap equiv_insn_bitmap (&reg_obstack);
5007   for (i = FIRST_PSEUDO_REGISTER; i < new_regno_start; i++)
5008     if (lra_reg_info[i].nrefs != 0)
5009       {
5010 	ira_reg_equiv[i].profitable_p = true;
5011 	reg = regno_reg_rtx[i];
5012 	if (lra_get_regno_hard_regno (i) < 0 && (x = get_equiv (reg)) != reg)
5013 	  {
5014 	    bool pseudo_p = contains_reg_p (x, false, false);
5015 
5016 	    /* After RTL transformation, we cannot guarantee that
5017 	       pseudo in the substitution was not reloaded which might
5018 	       make equivalence invalid.  For example, in reverse
5019 	       equiv of p0
5020 
5021 	       p0 <- ...
5022 	       ...
5023 	       equiv_mem <- p0
5024 
5025 	       the memory address register was reloaded before the 2nd
5026 	       insn.  */
5027 	    if ((! first_p && pseudo_p)
5028 		/* We don't use DF for compilation speed sake.  So it
5029 		   is problematic to update live info when we use an
5030 		   equivalence containing pseudos in more than one
5031 		   BB.  */
5032 		|| (pseudo_p && multi_block_pseudo_p (i))
5033 		/* If an init insn was deleted for some reason, cancel
5034 		   the equiv.  We could update the equiv insns after
5035 		   transformations including an equiv insn deletion
5036 		   but it is not worthy as such cases are extremely
5037 		   rare.  */
5038 		|| contains_deleted_insn_p (ira_reg_equiv[i].init_insns)
5039 		/* If it is not a reverse equivalence, we check that a
5040 		   pseudo in rhs of the init insn is not dying in the
5041 		   insn.  Otherwise, the live info at the beginning of
5042 		   the corresponding BB might be wrong after we
5043 		   removed the insn.  When the equiv can be a
5044 		   constant, the right hand side of the init insn can
5045 		   be a pseudo.  */
5046 		|| (! reverse_equiv_p (i)
5047 		    && (init_insn_rhs_dead_pseudo_p (i)
5048 			/* If we reloaded the pseudo in an equivalence
5049 			   init insn, we cannot remove the equiv init
5050 			   insns and the init insns might write into
5051 			   const memory in this case.  */
5052 			|| contains_reloaded_insn_p (i)))
5053 		/* Prevent access beyond equivalent memory for
5054 		   paradoxical subregs.  */
5055 		|| (MEM_P (x)
5056 		    && maybe_gt (GET_MODE_SIZE (lra_reg_info[i].biggest_mode),
5057 				 GET_MODE_SIZE (GET_MODE (x))))
5058 		|| (pic_offset_table_rtx
5059 		    && ((CONST_POOL_OK_P (PSEUDO_REGNO_MODE (i), x)
5060 			 && (targetm.preferred_reload_class
5061 			     (x, lra_get_allocno_class (i)) == NO_REGS))
5062 			|| contains_symbol_ref_p (x))))
5063 	      ira_reg_equiv[i].defined_p = false;
5064 	    if (contains_reg_p (x, false, true))
5065 	      ira_reg_equiv[i].profitable_p = false;
5066 	    if (get_equiv (reg) != reg)
5067 	      bitmap_ior_into (equiv_insn_bitmap, &lra_reg_info[i].insn_bitmap);
5068 	  }
5069       }
5070   for (i = FIRST_PSEUDO_REGISTER; i < new_regno_start; i++)
5071     update_equiv (i);
5072   /* We should add all insns containing pseudos which should be
5073      substituted by their equivalences.  */
5074   EXECUTE_IF_SET_IN_BITMAP (equiv_insn_bitmap, 0, uid, bi)
5075     lra_push_insn_by_uid (uid);
5076   min_len = lra_insn_stack_length ();
5077   new_insns_num = 0;
5078   last_bb = NULL;
5079   changed_p = false;
5080   while ((new_min_len = lra_insn_stack_length ()) != 0)
5081     {
5082       curr_insn = lra_pop_insn ();
5083       --new_min_len;
5084       curr_bb = BLOCK_FOR_INSN (curr_insn);
5085       if (curr_bb != last_bb)
5086 	{
5087 	  last_bb = curr_bb;
5088 	  bb_reload_num = lra_curr_reload_num;
5089 	}
5090       if (min_len > new_min_len)
5091 	{
5092 	  min_len = new_min_len;
5093 	  new_insns_num = 0;
5094 	}
5095       if (new_insns_num > MAX_RELOAD_INSNS_NUMBER)
5096 	internal_error
5097 	  ("maximum number of generated reload insns per insn achieved (%d)",
5098 	   MAX_RELOAD_INSNS_NUMBER);
5099       new_insns_num++;
5100       if (DEBUG_INSN_P (curr_insn))
5101 	{
5102 	  /* We need to check equivalence in debug insn and change
5103 	     pseudo to the equivalent value if necessary.  */
5104 	  curr_id = lra_get_insn_recog_data (curr_insn);
5105 	  if (bitmap_bit_p (equiv_insn_bitmap, INSN_UID (curr_insn)))
5106 	    {
5107 	      rtx old = *curr_id->operand_loc[0];
5108 	      *curr_id->operand_loc[0]
5109 		= simplify_replace_fn_rtx (old, NULL_RTX,
5110 					   loc_equivalence_callback, curr_insn);
5111 	      if (old != *curr_id->operand_loc[0])
5112 		{
5113 		  lra_update_insn_regno_info (curr_insn);
5114 		  changed_p = true;
5115 		}
5116 	    }
5117 	}
5118       else if (INSN_P (curr_insn))
5119 	{
5120 	  if ((set = single_set (curr_insn)) != NULL_RTX)
5121 	    {
5122 	      dest_reg = SET_DEST (set);
5123 	      /* The equivalence pseudo could be set up as SUBREG in a
5124 		 case when it is a call restore insn in a mode
5125 		 different from the pseudo mode.  */
5126 	      if (GET_CODE (dest_reg) == SUBREG)
5127 		dest_reg = SUBREG_REG (dest_reg);
5128 	      if ((REG_P (dest_reg)
5129 		   && (x = get_equiv (dest_reg)) != dest_reg
5130 		   /* Remove insns which set up a pseudo whose value
5131 		      cannot be changed.  Such insns might be not in
5132 		      init_insns because we don't update equiv data
5133 		      during insn transformations.
5134 
5135 		      As an example, let suppose that a pseudo got
5136 		      hard register and on the 1st pass was not
5137 		      changed to equivalent constant.  We generate an
5138 		      additional insn setting up the pseudo because of
5139 		      secondary memory movement.  Then the pseudo is
5140 		      spilled and we use the equiv constant.  In this
5141 		      case we should remove the additional insn and
5142 		      this insn is not init_insns list.  */
5143 		   && (! MEM_P (x) || MEM_READONLY_P (x)
5144 		       /* Check that this is actually an insn setting
5145 			  up the equivalence.  */
5146 		       || in_list_p (curr_insn,
5147 				     ira_reg_equiv
5148 				     [REGNO (dest_reg)].init_insns)))
5149 		  || (((x = get_equiv (SET_SRC (set))) != SET_SRC (set))
5150 		      && in_list_p (curr_insn,
5151 				    ira_reg_equiv
5152 				    [REGNO (SET_SRC (set))].init_insns)))
5153 		{
5154 		  /* This is equiv init insn of pseudo which did not get a
5155 		     hard register -- remove the insn.	*/
5156 		  if (lra_dump_file != NULL)
5157 		    {
5158 		      fprintf (lra_dump_file,
5159 			       "      Removing equiv init insn %i (freq=%d)\n",
5160 			       INSN_UID (curr_insn),
5161 			       REG_FREQ_FROM_BB (BLOCK_FOR_INSN (curr_insn)));
5162 		      dump_insn_slim (lra_dump_file, curr_insn);
5163 		    }
5164 		  if (contains_reg_p (x, true, false))
5165 		    check_and_force_assignment_correctness_p = true;
5166 		  lra_set_insn_deleted (curr_insn);
5167 		  continue;
5168 		}
5169 	    }
5170 	  curr_id = lra_get_insn_recog_data (curr_insn);
5171 	  curr_static_id = curr_id->insn_static_data;
5172 	  init_curr_insn_input_reloads ();
5173 	  init_curr_operand_mode ();
5174 	  if (curr_insn_transform (false))
5175 	    changed_p = true;
5176 	  /* Check non-transformed insns too for equiv change as USE
5177 	     or CLOBBER don't need reloads but can contain pseudos
5178 	     being changed on their equivalences.  */
5179 	  else if (bitmap_bit_p (equiv_insn_bitmap, INSN_UID (curr_insn))
5180 		   && loc_equivalence_change_p (&PATTERN (curr_insn)))
5181 	    {
5182 	      lra_update_insn_regno_info (curr_insn);
5183 	      changed_p = true;
5184 	    }
5185 	}
5186     }
5187 
5188   /* If we used a new hard regno, changed_p should be true because the
5189      hard reg is assigned to a new pseudo.  */
5190   if (flag_checking && !changed_p)
5191     {
5192       for (i = FIRST_PSEUDO_REGISTER; i < new_regno_start; i++)
5193 	if (lra_reg_info[i].nrefs != 0
5194 	    && (hard_regno = lra_get_regno_hard_regno (i)) >= 0)
5195 	  {
5196 	    int j, nregs = hard_regno_nregs (hard_regno,
5197 					     PSEUDO_REGNO_MODE (i));
5198 
5199 	    for (j = 0; j < nregs; j++)
5200 	      lra_assert (df_regs_ever_live_p (hard_regno + j));
5201 	  }
5202     }
5203   return changed_p;
5204 }
5205 
5206 static void initiate_invariants (void);
5207 static void finish_invariants (void);
5208 
5209 /* Initiate the LRA constraint pass.  It is done once per
5210    function.  */
5211 void
lra_constraints_init(void)5212 lra_constraints_init (void)
5213 {
5214   initiate_invariants ();
5215 }
5216 
5217 /* Finalize the LRA constraint pass.  It is done once per
5218    function.  */
5219 void
lra_constraints_finish(void)5220 lra_constraints_finish (void)
5221 {
5222   finish_invariants ();
5223 }
5224 
5225 
5226 
5227 /* Structure describes invariants for ineheritance.  */
5228 struct lra_invariant
5229 {
5230   /* The order number of the invariant.  */
5231   int num;
5232   /* The invariant RTX.  */
5233   rtx invariant_rtx;
5234   /* The origin insn of the invariant.  */
5235   rtx_insn *insn;
5236 };
5237 
5238 typedef lra_invariant invariant_t;
5239 typedef invariant_t *invariant_ptr_t;
5240 typedef const invariant_t *const_invariant_ptr_t;
5241 
5242 /* Pointer to the inheritance invariants.  */
5243 static vec<invariant_ptr_t> invariants;
5244 
5245 /* Allocation pool for the invariants.  */
5246 static object_allocator<lra_invariant> *invariants_pool;
5247 
5248 /* Hash table for the invariants.  */
5249 static htab_t invariant_table;
5250 
5251 /* Hash function for INVARIANT.  */
5252 static hashval_t
invariant_hash(const void * invariant)5253 invariant_hash (const void *invariant)
5254 {
5255   rtx inv = ((const_invariant_ptr_t) invariant)->invariant_rtx;
5256   return lra_rtx_hash (inv);
5257 }
5258 
5259 /* Equal function for invariants INVARIANT1 and INVARIANT2.  */
5260 static int
invariant_eq_p(const void * invariant1,const void * invariant2)5261 invariant_eq_p (const void *invariant1, const void *invariant2)
5262 {
5263   rtx inv1 = ((const_invariant_ptr_t) invariant1)->invariant_rtx;
5264   rtx inv2 = ((const_invariant_ptr_t) invariant2)->invariant_rtx;
5265 
5266   return rtx_equal_p (inv1, inv2);
5267 }
5268 
5269 /* Insert INVARIANT_RTX into the table if it is not there yet.  Return
5270    invariant which is in the table.  */
5271 static invariant_ptr_t
insert_invariant(rtx invariant_rtx)5272 insert_invariant (rtx invariant_rtx)
5273 {
5274   void **entry_ptr;
5275   invariant_t invariant;
5276   invariant_ptr_t invariant_ptr;
5277 
5278   invariant.invariant_rtx = invariant_rtx;
5279   entry_ptr = htab_find_slot (invariant_table, &invariant, INSERT);
5280   if (*entry_ptr == NULL)
5281     {
5282       invariant_ptr = invariants_pool->allocate ();
5283       invariant_ptr->invariant_rtx = invariant_rtx;
5284       invariant_ptr->insn = NULL;
5285       invariants.safe_push (invariant_ptr);
5286       *entry_ptr = (void *) invariant_ptr;
5287     }
5288   return (invariant_ptr_t) *entry_ptr;
5289 }
5290 
5291 /* Initiate the invariant table.  */
5292 static void
initiate_invariants(void)5293 initiate_invariants (void)
5294 {
5295   invariants.create (100);
5296   invariants_pool
5297     = new object_allocator<lra_invariant> ("Inheritance invariants");
5298   invariant_table = htab_create (100, invariant_hash, invariant_eq_p, NULL);
5299 }
5300 
5301 /* Finish the invariant table.  */
5302 static void
finish_invariants(void)5303 finish_invariants (void)
5304 {
5305   htab_delete (invariant_table);
5306   delete invariants_pool;
5307   invariants.release ();
5308 }
5309 
5310 /* Make the invariant table empty.  */
5311 static void
clear_invariants(void)5312 clear_invariants (void)
5313 {
5314   htab_empty (invariant_table);
5315   invariants_pool->release ();
5316   invariants.truncate (0);
5317 }
5318 
5319 
5320 
5321 /* This page contains code to do inheritance/split
5322    transformations.  */
5323 
5324 /* Number of reloads passed so far in current EBB.  */
5325 static int reloads_num;
5326 
5327 /* Number of calls passed so far in current EBB.  */
5328 static int calls_num;
5329 
5330 /* Index ID is the CALLS_NUM associated the last call we saw with
5331    ABI identifier ID.  */
5332 static int last_call_for_abi[NUM_ABI_IDS];
5333 
5334 /* Which registers have been fully or partially clobbered by a call
5335    since they were last used.  */
5336 static HARD_REG_SET full_and_partial_call_clobbers;
5337 
5338 /* Current reload pseudo check for validity of elements in
5339    USAGE_INSNS.	 */
5340 static int curr_usage_insns_check;
5341 
5342 /* Info about last usage of registers in EBB to do inheritance/split
5343    transformation.  Inheritance transformation is done from a spilled
5344    pseudo and split transformations from a hard register or a pseudo
5345    assigned to a hard register.	 */
5346 struct usage_insns
5347 {
5348   /* If the value is equal to CURR_USAGE_INSNS_CHECK, then the member
5349      value INSNS is valid.  The insns is chain of optional debug insns
5350      and a finishing non-debug insn using the corresponding reg.  The
5351      value is also used to mark the registers which are set up in the
5352      current insn.  The negated insn uid is used for this.  */
5353   int check;
5354   /* Value of global reloads_num at the last insn in INSNS.  */
5355   int reloads_num;
5356   /* Value of global reloads_nums at the last insn in INSNS.  */
5357   int calls_num;
5358   /* It can be true only for splitting.	 And it means that the restore
5359      insn should be put after insn given by the following member.  */
5360   bool after_p;
5361   /* Next insns in the current EBB which use the original reg and the
5362      original reg value is not changed between the current insn and
5363      the next insns.  In order words, e.g. for inheritance, if we need
5364      to use the original reg value again in the next insns we can try
5365      to use the value in a hard register from a reload insn of the
5366      current insn.  */
5367   rtx insns;
5368 };
5369 
5370 /* Map: regno -> corresponding pseudo usage insns.  */
5371 static struct usage_insns *usage_insns;
5372 
5373 static void
setup_next_usage_insn(int regno,rtx insn,int reloads_num,bool after_p)5374 setup_next_usage_insn (int regno, rtx insn, int reloads_num, bool after_p)
5375 {
5376   usage_insns[regno].check = curr_usage_insns_check;
5377   usage_insns[regno].insns = insn;
5378   usage_insns[regno].reloads_num = reloads_num;
5379   usage_insns[regno].calls_num = calls_num;
5380   usage_insns[regno].after_p = after_p;
5381   if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] >= 0)
5382     remove_from_hard_reg_set (&full_and_partial_call_clobbers,
5383 			      PSEUDO_REGNO_MODE (regno),
5384 			      reg_renumber[regno]);
5385 }
5386 
5387 /* The function is used to form list REGNO usages which consists of
5388    optional debug insns finished by a non-debug insn using REGNO.
5389    RELOADS_NUM is current number of reload insns processed so far.  */
5390 static void
add_next_usage_insn(int regno,rtx_insn * insn,int reloads_num)5391 add_next_usage_insn (int regno, rtx_insn *insn, int reloads_num)
5392 {
5393   rtx next_usage_insns;
5394 
5395   if (usage_insns[regno].check == curr_usage_insns_check
5396       && (next_usage_insns = usage_insns[regno].insns) != NULL_RTX
5397       && DEBUG_INSN_P (insn))
5398     {
5399       /* Check that we did not add the debug insn yet.	*/
5400       if (next_usage_insns != insn
5401 	  && (GET_CODE (next_usage_insns) != INSN_LIST
5402 	      || XEXP (next_usage_insns, 0) != insn))
5403 	usage_insns[regno].insns = gen_rtx_INSN_LIST (VOIDmode, insn,
5404 						      next_usage_insns);
5405     }
5406   else if (NONDEBUG_INSN_P (insn))
5407     setup_next_usage_insn (regno, insn, reloads_num, false);
5408   else
5409     usage_insns[regno].check = 0;
5410 }
5411 
5412 /* Return first non-debug insn in list USAGE_INSNS.  */
5413 static rtx_insn *
skip_usage_debug_insns(rtx usage_insns)5414 skip_usage_debug_insns (rtx usage_insns)
5415 {
5416   rtx insn;
5417 
5418   /* Skip debug insns.  */
5419   for (insn = usage_insns;
5420        insn != NULL_RTX && GET_CODE (insn) == INSN_LIST;
5421        insn = XEXP (insn, 1))
5422     ;
5423   return safe_as_a <rtx_insn *> (insn);
5424 }
5425 
5426 /* Return true if we need secondary memory moves for insn in
5427    USAGE_INSNS after inserting inherited pseudo of class INHER_CL
5428    into the insn.  */
5429 static bool
check_secondary_memory_needed_p(enum reg_class inher_cl ATTRIBUTE_UNUSED,rtx usage_insns ATTRIBUTE_UNUSED)5430 check_secondary_memory_needed_p (enum reg_class inher_cl ATTRIBUTE_UNUSED,
5431 				 rtx usage_insns ATTRIBUTE_UNUSED)
5432 {
5433   rtx_insn *insn;
5434   rtx set, dest;
5435   enum reg_class cl;
5436 
5437   if (inher_cl == ALL_REGS
5438       || (insn = skip_usage_debug_insns (usage_insns)) == NULL_RTX)
5439     return false;
5440   lra_assert (INSN_P (insn));
5441   if ((set = single_set (insn)) == NULL_RTX || ! REG_P (SET_DEST (set)))
5442     return false;
5443   dest = SET_DEST (set);
5444   if (! REG_P (dest))
5445     return false;
5446   lra_assert (inher_cl != NO_REGS);
5447   cl = get_reg_class (REGNO (dest));
5448   return (cl != NO_REGS && cl != ALL_REGS
5449 	  && targetm.secondary_memory_needed (GET_MODE (dest), inher_cl, cl));
5450 }
5451 
5452 /* Registers involved in inheritance/split in the current EBB
5453    (inheritance/split pseudos and original registers).	*/
5454 static bitmap_head check_only_regs;
5455 
5456 /* Reload pseudos cannot be involded in invariant inheritance in the
5457    current EBB.  */
5458 static bitmap_head invalid_invariant_regs;
5459 
5460 /* Do inheritance transformations for insn INSN, which defines (if
5461    DEF_P) or uses ORIGINAL_REGNO.  NEXT_USAGE_INSNS specifies which
5462    instruction in the EBB next uses ORIGINAL_REGNO; it has the same
5463    form as the "insns" field of usage_insns.  Return true if we
5464    succeed in such transformation.
5465 
5466    The transformations look like:
5467 
5468      p <- ...		  i <- ...
5469      ...		  p <- i    (new insn)
5470      ...	     =>
5471      <- ... p ...	  <- ... i ...
5472    or
5473      ...		  i <- p    (new insn)
5474      <- ... p ...	  <- ... i ...
5475      ...	     =>
5476      <- ... p ...	  <- ... i ...
5477    where p is a spilled original pseudo and i is a new inheritance pseudo.
5478 
5479 
5480    The inheritance pseudo has the smallest class of two classes CL and
5481    class of ORIGINAL REGNO.  */
5482 static bool
inherit_reload_reg(bool def_p,int original_regno,enum reg_class cl,rtx_insn * insn,rtx next_usage_insns)5483 inherit_reload_reg (bool def_p, int original_regno,
5484 		    enum reg_class cl, rtx_insn *insn, rtx next_usage_insns)
5485 {
5486   if (optimize_function_for_size_p (cfun))
5487     return false;
5488 
5489   enum reg_class rclass = lra_get_allocno_class (original_regno);
5490   rtx original_reg = regno_reg_rtx[original_regno];
5491   rtx new_reg, usage_insn;
5492   rtx_insn *new_insns;
5493 
5494   lra_assert (! usage_insns[original_regno].after_p);
5495   if (lra_dump_file != NULL)
5496     fprintf (lra_dump_file,
5497 	     "    <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
5498   if (! ira_reg_classes_intersect_p[cl][rclass])
5499     {
5500       if (lra_dump_file != NULL)
5501 	{
5502 	  fprintf (lra_dump_file,
5503 		   "    Rejecting inheritance for %d "
5504 		   "because of disjoint classes %s and %s\n",
5505 		   original_regno, reg_class_names[cl],
5506 		   reg_class_names[rclass]);
5507 	  fprintf (lra_dump_file,
5508 		   "    >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
5509 	}
5510       return false;
5511     }
5512   if ((ira_class_subset_p[cl][rclass] && cl != rclass)
5513       /* We don't use a subset of two classes because it can be
5514 	 NO_REGS.  This transformation is still profitable in most
5515 	 cases even if the classes are not intersected as register
5516 	 move is probably cheaper than a memory load.  */
5517       || ira_class_hard_regs_num[cl] < ira_class_hard_regs_num[rclass])
5518     {
5519       if (lra_dump_file != NULL)
5520 	fprintf (lra_dump_file, "    Use smallest class of %s and %s\n",
5521 		 reg_class_names[cl], reg_class_names[rclass]);
5522 
5523       rclass = cl;
5524     }
5525   if (check_secondary_memory_needed_p (rclass, next_usage_insns))
5526     {
5527       /* Reject inheritance resulting in secondary memory moves.
5528 	 Otherwise, there is a danger in LRA cycling.  Also such
5529 	 transformation will be unprofitable.  */
5530       if (lra_dump_file != NULL)
5531 	{
5532 	  rtx_insn *insn = skip_usage_debug_insns (next_usage_insns);
5533 	  rtx set = single_set (insn);
5534 
5535 	  lra_assert (set != NULL_RTX);
5536 
5537 	  rtx dest = SET_DEST (set);
5538 
5539 	  lra_assert (REG_P (dest));
5540 	  fprintf (lra_dump_file,
5541 		   "    Rejecting inheritance for insn %d(%s)<-%d(%s) "
5542 		   "as secondary mem is needed\n",
5543 		   REGNO (dest), reg_class_names[get_reg_class (REGNO (dest))],
5544 		   original_regno, reg_class_names[rclass]);
5545 	  fprintf (lra_dump_file,
5546 		   "    >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
5547 	}
5548       return false;
5549     }
5550   new_reg = lra_create_new_reg (GET_MODE (original_reg), original_reg,
5551 				rclass, "inheritance");
5552   start_sequence ();
5553   if (def_p)
5554     lra_emit_move (original_reg, new_reg);
5555   else
5556     lra_emit_move (new_reg, original_reg);
5557   new_insns = get_insns ();
5558   end_sequence ();
5559   if (NEXT_INSN (new_insns) != NULL_RTX)
5560     {
5561       if (lra_dump_file != NULL)
5562 	{
5563 	  fprintf (lra_dump_file,
5564 		   "    Rejecting inheritance %d->%d "
5565 		   "as it results in 2 or more insns:\n",
5566 		   original_regno, REGNO (new_reg));
5567 	  dump_rtl_slim (lra_dump_file, new_insns, NULL, -1, 0);
5568 	  fprintf (lra_dump_file,
5569 		   "	>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
5570 	}
5571       return false;
5572     }
5573   lra_substitute_pseudo_within_insn (insn, original_regno, new_reg, false);
5574   lra_update_insn_regno_info (insn);
5575   if (! def_p)
5576     /* We now have a new usage insn for original regno.  */
5577     setup_next_usage_insn (original_regno, new_insns, reloads_num, false);
5578   if (lra_dump_file != NULL)
5579     fprintf (lra_dump_file, "    Original reg change %d->%d (bb%d):\n",
5580 	     original_regno, REGNO (new_reg), BLOCK_FOR_INSN (insn)->index);
5581   lra_reg_info[REGNO (new_reg)].restore_rtx = regno_reg_rtx[original_regno];
5582   bitmap_set_bit (&check_only_regs, REGNO (new_reg));
5583   bitmap_set_bit (&check_only_regs, original_regno);
5584   bitmap_set_bit (&lra_inheritance_pseudos, REGNO (new_reg));
5585   if (def_p)
5586     lra_process_new_insns (insn, NULL, new_insns,
5587 			   "Add original<-inheritance");
5588   else
5589     lra_process_new_insns (insn, new_insns, NULL,
5590 			   "Add inheritance<-original");
5591   while (next_usage_insns != NULL_RTX)
5592     {
5593       if (GET_CODE (next_usage_insns) != INSN_LIST)
5594 	{
5595 	  usage_insn = next_usage_insns;
5596 	  lra_assert (NONDEBUG_INSN_P (usage_insn));
5597 	  next_usage_insns = NULL;
5598 	}
5599       else
5600 	{
5601 	  usage_insn = XEXP (next_usage_insns, 0);
5602 	  lra_assert (DEBUG_INSN_P (usage_insn));
5603 	  next_usage_insns = XEXP (next_usage_insns, 1);
5604 	}
5605       lra_substitute_pseudo (&usage_insn, original_regno, new_reg, false,
5606 			     DEBUG_INSN_P (usage_insn));
5607       lra_update_insn_regno_info (as_a <rtx_insn *> (usage_insn));
5608       if (lra_dump_file != NULL)
5609 	{
5610 	  basic_block bb = BLOCK_FOR_INSN (usage_insn);
5611 	  fprintf (lra_dump_file,
5612 		   "    Inheritance reuse change %d->%d (bb%d):\n",
5613 		   original_regno, REGNO (new_reg),
5614 		   bb ? bb->index : -1);
5615 	  dump_insn_slim (lra_dump_file, as_a <rtx_insn *> (usage_insn));
5616 	}
5617     }
5618   if (lra_dump_file != NULL)
5619     fprintf (lra_dump_file,
5620 	     "	  >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
5621   return true;
5622 }
5623 
5624 /* Return true if we need a caller save/restore for pseudo REGNO which
5625    was assigned to a hard register.  */
5626 static inline bool
need_for_call_save_p(int regno)5627 need_for_call_save_p (int regno)
5628 {
5629   lra_assert (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] >= 0);
5630   if (usage_insns[regno].calls_num < calls_num)
5631     {
5632       unsigned int abis = 0;
5633       for (unsigned int i = 0; i < NUM_ABI_IDS; ++i)
5634 	if (last_call_for_abi[i] > usage_insns[regno].calls_num)
5635 	  abis |= 1 << i;
5636       gcc_assert (abis);
5637       if (call_clobbered_in_region_p (abis, full_and_partial_call_clobbers,
5638 				      PSEUDO_REGNO_MODE (regno),
5639 				      reg_renumber[regno]))
5640 	return true;
5641     }
5642   return false;
5643 }
5644 
5645 /* Global registers occurring in the current EBB.  */
5646 static bitmap_head ebb_global_regs;
5647 
5648 /* Return true if we need a split for hard register REGNO or pseudo
5649    REGNO which was assigned to a hard register.
5650    POTENTIAL_RELOAD_HARD_REGS contains hard registers which might be
5651    used for reloads since the EBB end.	It is an approximation of the
5652    used hard registers in the split range.  The exact value would
5653    require expensive calculations.  If we were aggressive with
5654    splitting because of the approximation, the split pseudo will save
5655    the same hard register assignment and will be removed in the undo
5656    pass.  We still need the approximation because too aggressive
5657    splitting would result in too inaccurate cost calculation in the
5658    assignment pass because of too many generated moves which will be
5659    probably removed in the undo pass.  */
5660 static inline bool
need_for_split_p(HARD_REG_SET potential_reload_hard_regs,int regno)5661 need_for_split_p (HARD_REG_SET potential_reload_hard_regs, int regno)
5662 {
5663   int hard_regno = regno < FIRST_PSEUDO_REGISTER ? regno : reg_renumber[regno];
5664 
5665   lra_assert (hard_regno >= 0);
5666   return ((TEST_HARD_REG_BIT (potential_reload_hard_regs, hard_regno)
5667 	   /* Don't split eliminable hard registers, otherwise we can
5668 	      split hard registers like hard frame pointer, which
5669 	      lives on BB start/end according to DF-infrastructure,
5670 	      when there is a pseudo assigned to the register and
5671 	      living in the same BB.  */
5672 	   && (regno >= FIRST_PSEUDO_REGISTER
5673 	       || ! TEST_HARD_REG_BIT (eliminable_regset, hard_regno))
5674 	   && ! TEST_HARD_REG_BIT (lra_no_alloc_regs, hard_regno)
5675 	   /* Don't split call clobbered hard regs living through
5676 	      calls, otherwise we might have a check problem in the
5677 	      assign sub-pass as in the most cases (exception is a
5678 	      situation when check_and_force_assignment_correctness_p value is
5679 	      true) the assign pass assumes that all pseudos living
5680 	      through calls are assigned to call saved hard regs.  */
5681 	   && (regno >= FIRST_PSEUDO_REGISTER
5682 	       || !TEST_HARD_REG_BIT (full_and_partial_call_clobbers, regno))
5683 	   /* We need at least 2 reloads to make pseudo splitting
5684 	      profitable.  We should provide hard regno splitting in
5685 	      any case to solve 1st insn scheduling problem when
5686 	      moving hard register definition up might result in
5687 	      impossibility to find hard register for reload pseudo of
5688 	      small register class.  */
5689 	   && (usage_insns[regno].reloads_num
5690 	       + (regno < FIRST_PSEUDO_REGISTER ? 0 : 3) < reloads_num)
5691 	   && (regno < FIRST_PSEUDO_REGISTER
5692 	       /* For short living pseudos, spilling + inheritance can
5693 		  be considered a substitution for splitting.
5694 		  Therefore we do not splitting for local pseudos.  It
5695 		  decreases also aggressiveness of splitting.  The
5696 		  minimal number of references is chosen taking into
5697 		  account that for 2 references splitting has no sense
5698 		  as we can just spill the pseudo.  */
5699 	       || (regno >= FIRST_PSEUDO_REGISTER
5700 		   && lra_reg_info[regno].nrefs > 3
5701 		   && bitmap_bit_p (&ebb_global_regs, regno))))
5702 	  || (regno >= FIRST_PSEUDO_REGISTER && need_for_call_save_p (regno)));
5703 }
5704 
5705 /* Return class for the split pseudo created from original pseudo with
5706    ALLOCNO_CLASS and MODE which got a hard register HARD_REGNO.	 We
5707    choose subclass of ALLOCNO_CLASS which contains HARD_REGNO and
5708    results in no secondary memory movements.  */
5709 static enum reg_class
choose_split_class(enum reg_class allocno_class,int hard_regno ATTRIBUTE_UNUSED,machine_mode mode ATTRIBUTE_UNUSED)5710 choose_split_class (enum reg_class allocno_class,
5711 		    int hard_regno ATTRIBUTE_UNUSED,
5712 		    machine_mode mode ATTRIBUTE_UNUSED)
5713 {
5714   int i;
5715   enum reg_class cl, best_cl = NO_REGS;
5716   enum reg_class hard_reg_class ATTRIBUTE_UNUSED
5717     = REGNO_REG_CLASS (hard_regno);
5718 
5719   if (! targetm.secondary_memory_needed (mode, allocno_class, allocno_class)
5720       && TEST_HARD_REG_BIT (reg_class_contents[allocno_class], hard_regno))
5721     return allocno_class;
5722   for (i = 0;
5723        (cl = reg_class_subclasses[allocno_class][i]) != LIM_REG_CLASSES;
5724        i++)
5725     if (! targetm.secondary_memory_needed (mode, cl, hard_reg_class)
5726 	&& ! targetm.secondary_memory_needed (mode, hard_reg_class, cl)
5727 	&& TEST_HARD_REG_BIT (reg_class_contents[cl], hard_regno)
5728 	&& (best_cl == NO_REGS
5729 	    || ira_class_hard_regs_num[best_cl] < ira_class_hard_regs_num[cl]))
5730       best_cl = cl;
5731   return best_cl;
5732 }
5733 
5734 /* Copy any equivalence information from ORIGINAL_REGNO to NEW_REGNO.
5735    It only makes sense to call this function if NEW_REGNO is always
5736    equal to ORIGINAL_REGNO.  */
5737 
5738 static void
lra_copy_reg_equiv(unsigned int new_regno,unsigned int original_regno)5739 lra_copy_reg_equiv (unsigned int new_regno, unsigned int original_regno)
5740 {
5741   if (!ira_reg_equiv[original_regno].defined_p)
5742     return;
5743 
5744   ira_expand_reg_equiv ();
5745   ira_reg_equiv[new_regno].defined_p = true;
5746   if (ira_reg_equiv[original_regno].memory)
5747     ira_reg_equiv[new_regno].memory
5748       = copy_rtx (ira_reg_equiv[original_regno].memory);
5749   if (ira_reg_equiv[original_regno].constant)
5750     ira_reg_equiv[new_regno].constant
5751       = copy_rtx (ira_reg_equiv[original_regno].constant);
5752   if (ira_reg_equiv[original_regno].invariant)
5753     ira_reg_equiv[new_regno].invariant
5754       = copy_rtx (ira_reg_equiv[original_regno].invariant);
5755 }
5756 
5757 /* Do split transformations for insn INSN, which defines or uses
5758    ORIGINAL_REGNO.  NEXT_USAGE_INSNS specifies which instruction in
5759    the EBB next uses ORIGINAL_REGNO; it has the same form as the
5760    "insns" field of usage_insns.  If TO is not NULL, we don't use
5761    usage_insns, we put restore insns after TO insn.  It is a case when
5762    we call it from lra_split_hard_reg_for, outside the inheritance
5763    pass.
5764 
5765    The transformations look like:
5766 
5767      p <- ...		  p <- ...
5768      ...		  s <- p    (new insn -- save)
5769      ...	     =>
5770      ...		  p <- s    (new insn -- restore)
5771      <- ... p ...	  <- ... p ...
5772    or
5773      <- ... p ...	  <- ... p ...
5774      ...		  s <- p    (new insn -- save)
5775      ...	     =>
5776      ...		  p <- s    (new insn -- restore)
5777      <- ... p ...	  <- ... p ...
5778 
5779    where p is an original pseudo got a hard register or a hard
5780    register and s is a new split pseudo.  The save is put before INSN
5781    if BEFORE_P is true.	 Return true if we succeed in such
5782    transformation.  */
5783 static bool
split_reg(bool before_p,int original_regno,rtx_insn * insn,rtx next_usage_insns,rtx_insn * to)5784 split_reg (bool before_p, int original_regno, rtx_insn *insn,
5785 	   rtx next_usage_insns, rtx_insn *to)
5786 {
5787   enum reg_class rclass;
5788   rtx original_reg;
5789   int hard_regno, nregs;
5790   rtx new_reg, usage_insn;
5791   rtx_insn *restore, *save;
5792   bool after_p;
5793   bool call_save_p;
5794   machine_mode mode;
5795 
5796   if (original_regno < FIRST_PSEUDO_REGISTER)
5797     {
5798       rclass = ira_allocno_class_translate[REGNO_REG_CLASS (original_regno)];
5799       hard_regno = original_regno;
5800       call_save_p = false;
5801       nregs = 1;
5802       mode = lra_reg_info[hard_regno].biggest_mode;
5803       machine_mode reg_rtx_mode = GET_MODE (regno_reg_rtx[hard_regno]);
5804       /* A reg can have a biggest_mode of VOIDmode if it was only ever seen as
5805 	 part of a multi-word register.  In that case, just use the reg_rtx
5806 	 mode.  Do the same also if the biggest mode was larger than a register
5807 	 or we can not compare the modes.  Otherwise, limit the size to that of
5808 	 the biggest access in the function.  */
5809       if (mode == VOIDmode
5810 	  || !ordered_p (GET_MODE_PRECISION (mode),
5811 			 GET_MODE_PRECISION (reg_rtx_mode))
5812 	  || paradoxical_subreg_p (mode, reg_rtx_mode))
5813 	{
5814 	  original_reg = regno_reg_rtx[hard_regno];
5815 	  mode = reg_rtx_mode;
5816 	}
5817       else
5818 	original_reg = gen_rtx_REG (mode, hard_regno);
5819     }
5820   else
5821     {
5822       mode = PSEUDO_REGNO_MODE (original_regno);
5823       hard_regno = reg_renumber[original_regno];
5824       nregs = hard_regno_nregs (hard_regno, mode);
5825       rclass = lra_get_allocno_class (original_regno);
5826       original_reg = regno_reg_rtx[original_regno];
5827       call_save_p = need_for_call_save_p (original_regno);
5828     }
5829   lra_assert (hard_regno >= 0);
5830   if (lra_dump_file != NULL)
5831     fprintf (lra_dump_file,
5832 	     "	  ((((((((((((((((((((((((((((((((((((((((((((((((\n");
5833 
5834   if (call_save_p)
5835     {
5836       mode = HARD_REGNO_CALLER_SAVE_MODE (hard_regno,
5837 					  hard_regno_nregs (hard_regno, mode),
5838 					  mode);
5839       new_reg = lra_create_new_reg (mode, NULL_RTX, NO_REGS, "save");
5840     }
5841   else
5842     {
5843       rclass = choose_split_class (rclass, hard_regno, mode);
5844       if (rclass == NO_REGS)
5845 	{
5846 	  if (lra_dump_file != NULL)
5847 	    {
5848 	      fprintf (lra_dump_file,
5849 		       "    Rejecting split of %d(%s): "
5850 		       "no good reg class for %d(%s)\n",
5851 		       original_regno,
5852 		       reg_class_names[lra_get_allocno_class (original_regno)],
5853 		       hard_regno,
5854 		       reg_class_names[REGNO_REG_CLASS (hard_regno)]);
5855 	      fprintf
5856 		(lra_dump_file,
5857 		 "    ))))))))))))))))))))))))))))))))))))))))))))))))\n");
5858 	    }
5859 	  return false;
5860 	}
5861       /* Split_if_necessary can split hard registers used as part of a
5862 	 multi-register mode but splits each register individually.  The
5863 	 mode used for each independent register may not be supported
5864 	 so reject the split.  Splitting the wider mode should theoretically
5865 	 be possible but is not implemented.  */
5866       if (!targetm.hard_regno_mode_ok (hard_regno, mode))
5867 	{
5868 	  if (lra_dump_file != NULL)
5869 	    {
5870 	      fprintf (lra_dump_file,
5871 		       "    Rejecting split of %d(%s): unsuitable mode %s\n",
5872 		       original_regno,
5873 		       reg_class_names[lra_get_allocno_class (original_regno)],
5874 		       GET_MODE_NAME (mode));
5875 	      fprintf
5876 		(lra_dump_file,
5877 		 "    ))))))))))))))))))))))))))))))))))))))))))))))))\n");
5878 	    }
5879 	  return false;
5880 	}
5881       new_reg = lra_create_new_reg (mode, original_reg, rclass, "split");
5882       reg_renumber[REGNO (new_reg)] = hard_regno;
5883     }
5884   int new_regno = REGNO (new_reg);
5885   save = emit_spill_move (true, new_reg, original_reg);
5886   if (NEXT_INSN (save) != NULL_RTX && !call_save_p)
5887     {
5888       if (lra_dump_file != NULL)
5889 	{
5890 	  fprintf
5891 	    (lra_dump_file,
5892 	     "	  Rejecting split %d->%d resulting in > 2 save insns:\n",
5893 	     original_regno, new_regno);
5894 	  dump_rtl_slim (lra_dump_file, save, NULL, -1, 0);
5895 	  fprintf (lra_dump_file,
5896 		   "	))))))))))))))))))))))))))))))))))))))))))))))))\n");
5897 	}
5898       return false;
5899     }
5900   restore = emit_spill_move (false, new_reg, original_reg);
5901   if (NEXT_INSN (restore) != NULL_RTX && !call_save_p)
5902     {
5903       if (lra_dump_file != NULL)
5904 	{
5905 	  fprintf (lra_dump_file,
5906 		   "	Rejecting split %d->%d "
5907 		   "resulting in > 2 restore insns:\n",
5908 		   original_regno, new_regno);
5909 	  dump_rtl_slim (lra_dump_file, restore, NULL, -1, 0);
5910 	  fprintf (lra_dump_file,
5911 		   "	))))))))))))))))))))))))))))))))))))))))))))))))\n");
5912 	}
5913       return false;
5914     }
5915   /* Transfer equivalence information to the spill register, so that
5916      if we fail to allocate the spill register, we have the option of
5917      rematerializing the original value instead of spilling to the stack.  */
5918   if (!HARD_REGISTER_NUM_P (original_regno)
5919       && mode == PSEUDO_REGNO_MODE (original_regno))
5920     lra_copy_reg_equiv (new_regno, original_regno);
5921   lra_reg_info[new_regno].restore_rtx = regno_reg_rtx[original_regno];
5922   bitmap_set_bit (&lra_split_regs, new_regno);
5923   if (to != NULL)
5924     {
5925       lra_assert (next_usage_insns == NULL);
5926       usage_insn = to;
5927       after_p = TRUE;
5928     }
5929   else
5930     {
5931       /* We need check_only_regs only inside the inheritance pass.  */
5932       bitmap_set_bit (&check_only_regs, new_regno);
5933       bitmap_set_bit (&check_only_regs, original_regno);
5934       after_p = usage_insns[original_regno].after_p;
5935       for (;;)
5936 	{
5937 	  if (GET_CODE (next_usage_insns) != INSN_LIST)
5938 	    {
5939 	      usage_insn = next_usage_insns;
5940 	      break;
5941 	    }
5942 	  usage_insn = XEXP (next_usage_insns, 0);
5943 	  lra_assert (DEBUG_INSN_P (usage_insn));
5944 	  next_usage_insns = XEXP (next_usage_insns, 1);
5945 	  lra_substitute_pseudo (&usage_insn, original_regno, new_reg, false,
5946 				 true);
5947 	  lra_update_insn_regno_info (as_a <rtx_insn *> (usage_insn));
5948 	  if (lra_dump_file != NULL)
5949 	    {
5950 	      fprintf (lra_dump_file, "    Split reuse change %d->%d:\n",
5951 		       original_regno, new_regno);
5952 	      dump_insn_slim (lra_dump_file, as_a <rtx_insn *> (usage_insn));
5953 	    }
5954 	}
5955     }
5956   lra_assert (NOTE_P (usage_insn) || NONDEBUG_INSN_P (usage_insn));
5957   lra_assert (usage_insn != insn || (after_p && before_p));
5958   lra_process_new_insns (as_a <rtx_insn *> (usage_insn),
5959 			 after_p ? NULL : restore,
5960 			 after_p ? restore : NULL,
5961 			 call_save_p
5962 			 ?  "Add reg<-save" : "Add reg<-split");
5963   lra_process_new_insns (insn, before_p ? save : NULL,
5964 			 before_p ? NULL : save,
5965 			 call_save_p
5966 			 ?  "Add save<-reg" : "Add split<-reg");
5967   if (nregs > 1)
5968     /* If we are trying to split multi-register.  We should check
5969        conflicts on the next assignment sub-pass.  IRA can allocate on
5970        sub-register levels, LRA do this on pseudos level right now and
5971        this discrepancy may create allocation conflicts after
5972        splitting.  */
5973     check_and_force_assignment_correctness_p = true;
5974   if (lra_dump_file != NULL)
5975     fprintf (lra_dump_file,
5976 	     "	  ))))))))))))))))))))))))))))))))))))))))))))))))\n");
5977   return true;
5978 }
5979 
5980 /* Split a hard reg for reload pseudo REGNO having RCLASS and living
5981    in the range [FROM, TO].  Return true if did a split.  Otherwise,
5982    return false.  */
5983 bool
spill_hard_reg_in_range(int regno,enum reg_class rclass,rtx_insn * from,rtx_insn * to)5984 spill_hard_reg_in_range (int regno, enum reg_class rclass, rtx_insn *from, rtx_insn *to)
5985 {
5986   int i, hard_regno;
5987   int rclass_size;
5988   rtx_insn *insn;
5989   unsigned int uid;
5990   bitmap_iterator bi;
5991   HARD_REG_SET ignore;
5992 
5993   lra_assert (from != NULL && to != NULL);
5994   CLEAR_HARD_REG_SET (ignore);
5995   EXECUTE_IF_SET_IN_BITMAP (&lra_reg_info[regno].insn_bitmap, 0, uid, bi)
5996     {
5997       lra_insn_recog_data_t id = lra_insn_recog_data[uid];
5998       struct lra_static_insn_data *static_id = id->insn_static_data;
5999       struct lra_insn_reg *reg;
6000 
6001       for (reg = id->regs; reg != NULL; reg = reg->next)
6002 	if (reg->regno < FIRST_PSEUDO_REGISTER)
6003 	  SET_HARD_REG_BIT (ignore, reg->regno);
6004       for (reg = static_id->hard_regs; reg != NULL; reg = reg->next)
6005 	SET_HARD_REG_BIT (ignore, reg->regno);
6006     }
6007   rclass_size = ira_class_hard_regs_num[rclass];
6008   for (i = 0; i < rclass_size; i++)
6009     {
6010       hard_regno = ira_class_hard_regs[rclass][i];
6011       if (! TEST_HARD_REG_BIT (lra_reg_info[regno].conflict_hard_regs, hard_regno)
6012 	  || TEST_HARD_REG_BIT (ignore, hard_regno))
6013 	continue;
6014       for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn))
6015 	{
6016 	  struct lra_static_insn_data *static_id;
6017 	  struct lra_insn_reg *reg;
6018 
6019 	  if (!INSN_P (insn))
6020 	      continue;
6021 	  if (bitmap_bit_p (&lra_reg_info[hard_regno].insn_bitmap,
6022 			    INSN_UID (insn)))
6023 	    break;
6024 	  static_id = lra_get_insn_recog_data (insn)->insn_static_data;
6025 	  for (reg = static_id->hard_regs; reg != NULL; reg = reg->next)
6026 	    if (reg->regno == hard_regno)
6027 	      break;
6028 	  if (reg != NULL)
6029 	    break;
6030 	}
6031       if (insn != NEXT_INSN (to))
6032 	continue;
6033       if (split_reg (TRUE, hard_regno, from, NULL, to))
6034 	return true;
6035     }
6036   return false;
6037 }
6038 
6039 /* Recognize that we need a split transformation for insn INSN, which
6040    defines or uses REGNO in its insn biggest MODE (we use it only if
6041    REGNO is a hard register).  POTENTIAL_RELOAD_HARD_REGS contains
6042    hard registers which might be used for reloads since the EBB end.
6043    Put the save before INSN if BEFORE_P is true.  MAX_UID is maximla
6044    uid before starting INSN processing.  Return true if we succeed in
6045    such transformation.  */
6046 static bool
split_if_necessary(int regno,machine_mode mode,HARD_REG_SET potential_reload_hard_regs,bool before_p,rtx_insn * insn,int max_uid)6047 split_if_necessary (int regno, machine_mode mode,
6048 		    HARD_REG_SET potential_reload_hard_regs,
6049 		    bool before_p, rtx_insn *insn, int max_uid)
6050 {
6051   bool res = false;
6052   int i, nregs = 1;
6053   rtx next_usage_insns;
6054 
6055   if (regno < FIRST_PSEUDO_REGISTER)
6056     nregs = hard_regno_nregs (regno, mode);
6057   for (i = 0; i < nregs; i++)
6058     if (usage_insns[regno + i].check == curr_usage_insns_check
6059 	&& (next_usage_insns = usage_insns[regno + i].insns) != NULL_RTX
6060 	/* To avoid processing the register twice or more.  */
6061 	&& ((GET_CODE (next_usage_insns) != INSN_LIST
6062 	     && INSN_UID (next_usage_insns) < max_uid)
6063 	    || (GET_CODE (next_usage_insns) == INSN_LIST
6064 		&& (INSN_UID (XEXP (next_usage_insns, 0)) < max_uid)))
6065 	&& need_for_split_p (potential_reload_hard_regs, regno + i)
6066 	&& split_reg (before_p, regno + i, insn, next_usage_insns, NULL))
6067     res = true;
6068   return res;
6069 }
6070 
6071 /* Return TRUE if rtx X is considered as an invariant for
6072    inheritance.  */
6073 static bool
invariant_p(const_rtx x)6074 invariant_p (const_rtx x)
6075 {
6076   machine_mode mode;
6077   const char *fmt;
6078   enum rtx_code code;
6079   int i, j;
6080 
6081   if (side_effects_p (x))
6082     return false;
6083 
6084   code = GET_CODE (x);
6085   mode = GET_MODE (x);
6086   if (code == SUBREG)
6087     {
6088       x = SUBREG_REG (x);
6089       code = GET_CODE (x);
6090       mode = wider_subreg_mode (mode, GET_MODE (x));
6091     }
6092 
6093   if (MEM_P (x))
6094     return false;
6095 
6096   if (REG_P (x))
6097     {
6098       int i, nregs, regno = REGNO (x);
6099 
6100       if (regno >= FIRST_PSEUDO_REGISTER || regno == STACK_POINTER_REGNUM
6101 	  || TEST_HARD_REG_BIT (eliminable_regset, regno)
6102 	  || GET_MODE_CLASS (GET_MODE (x)) == MODE_CC)
6103 	return false;
6104       nregs = hard_regno_nregs (regno, mode);
6105       for (i = 0; i < nregs; i++)
6106 	if (! fixed_regs[regno + i]
6107 	    /* A hard register may be clobbered in the current insn
6108 	       but we can ignore this case because if the hard
6109 	       register is used it should be set somewhere after the
6110 	       clobber.  */
6111 	    || bitmap_bit_p (&invalid_invariant_regs, regno + i))
6112 	  return false;
6113     }
6114   fmt = GET_RTX_FORMAT (code);
6115   for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
6116     {
6117       if (fmt[i] == 'e')
6118 	{
6119 	  if (! invariant_p (XEXP (x, i)))
6120 	    return false;
6121 	}
6122       else if (fmt[i] == 'E')
6123 	{
6124 	  for (j = XVECLEN (x, i) - 1; j >= 0; j--)
6125 	    if (! invariant_p (XVECEXP (x, i, j)))
6126 	      return false;
6127 	}
6128     }
6129   return true;
6130 }
6131 
6132 /* We have 'dest_reg <- invariant'.  Let us try to make an invariant
6133    inheritance transformation (using dest_reg instead invariant in a
6134    subsequent insn).  */
6135 static bool
process_invariant_for_inheritance(rtx dst_reg,rtx invariant_rtx)6136 process_invariant_for_inheritance (rtx dst_reg, rtx invariant_rtx)
6137 {
6138   invariant_ptr_t invariant_ptr;
6139   rtx_insn *insn, *new_insns;
6140   rtx insn_set, insn_reg, new_reg;
6141   int insn_regno;
6142   bool succ_p = false;
6143   int dst_regno = REGNO (dst_reg);
6144   machine_mode dst_mode = GET_MODE (dst_reg);
6145   enum reg_class cl = lra_get_allocno_class (dst_regno), insn_reg_cl;
6146 
6147   invariant_ptr = insert_invariant (invariant_rtx);
6148   if ((insn = invariant_ptr->insn) != NULL_RTX)
6149     {
6150       /* We have a subsequent insn using the invariant.  */
6151       insn_set = single_set (insn);
6152       lra_assert (insn_set != NULL);
6153       insn_reg = SET_DEST (insn_set);
6154       lra_assert (REG_P (insn_reg));
6155       insn_regno = REGNO (insn_reg);
6156       insn_reg_cl = lra_get_allocno_class (insn_regno);
6157 
6158       if (dst_mode == GET_MODE (insn_reg)
6159 	  /* We should consider only result move reg insns which are
6160 	     cheap.  */
6161 	  && targetm.register_move_cost (dst_mode, cl, insn_reg_cl) == 2
6162 	  && targetm.register_move_cost (dst_mode, cl, cl) == 2)
6163 	{
6164 	  if (lra_dump_file != NULL)
6165 	    fprintf (lra_dump_file,
6166 		     "    [[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[\n");
6167 	  new_reg = lra_create_new_reg (dst_mode, dst_reg,
6168 					cl, "invariant inheritance");
6169 	  bitmap_set_bit (&lra_inheritance_pseudos, REGNO (new_reg));
6170 	  bitmap_set_bit (&check_only_regs, REGNO (new_reg));
6171 	  lra_reg_info[REGNO (new_reg)].restore_rtx = PATTERN (insn);
6172 	  start_sequence ();
6173 	  lra_emit_move (new_reg, dst_reg);
6174 	  new_insns = get_insns ();
6175 	  end_sequence ();
6176 	  lra_process_new_insns (curr_insn, NULL, new_insns,
6177 				 "Add invariant inheritance<-original");
6178 	  start_sequence ();
6179 	  lra_emit_move (SET_DEST (insn_set), new_reg);
6180 	  new_insns = get_insns ();
6181 	  end_sequence ();
6182 	  lra_process_new_insns (insn, NULL, new_insns,
6183 				 "Changing reload<-inheritance");
6184 	  lra_set_insn_deleted (insn);
6185 	  succ_p = true;
6186 	  if (lra_dump_file != NULL)
6187 	    {
6188 	      fprintf (lra_dump_file,
6189 		       "    Invariant inheritance reuse change %d (bb%d):\n",
6190 		       REGNO (new_reg), BLOCK_FOR_INSN (insn)->index);
6191 	      dump_insn_slim (lra_dump_file, insn);
6192 	      fprintf (lra_dump_file,
6193 		       "	  ]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]\n");
6194 	    }
6195 	}
6196     }
6197   invariant_ptr->insn = curr_insn;
6198   return succ_p;
6199 }
6200 
6201 /* Check only registers living at the current program point in the
6202    current EBB.	 */
6203 static bitmap_head live_regs;
6204 
6205 /* Update live info in EBB given by its HEAD and TAIL insns after
6206    inheritance/split transformation.  The function removes dead moves
6207    too.	 */
6208 static void
update_ebb_live_info(rtx_insn * head,rtx_insn * tail)6209 update_ebb_live_info (rtx_insn *head, rtx_insn *tail)
6210 {
6211   unsigned int j;
6212   int i, regno;
6213   bool live_p;
6214   rtx_insn *prev_insn;
6215   rtx set;
6216   bool remove_p;
6217   basic_block last_bb, prev_bb, curr_bb;
6218   bitmap_iterator bi;
6219   struct lra_insn_reg *reg;
6220   edge e;
6221   edge_iterator ei;
6222 
6223   last_bb = BLOCK_FOR_INSN (tail);
6224   prev_bb = NULL;
6225   for (curr_insn = tail;
6226        curr_insn != PREV_INSN (head);
6227        curr_insn = prev_insn)
6228     {
6229       prev_insn = PREV_INSN (curr_insn);
6230       /* We need to process empty blocks too.  They contain
6231 	 NOTE_INSN_BASIC_BLOCK referring for the basic block.  */
6232       if (NOTE_P (curr_insn) && NOTE_KIND (curr_insn) != NOTE_INSN_BASIC_BLOCK)
6233 	continue;
6234       curr_bb = BLOCK_FOR_INSN (curr_insn);
6235       if (curr_bb != prev_bb)
6236 	{
6237 	  if (prev_bb != NULL)
6238 	    {
6239 	      /* Update df_get_live_in (prev_bb):  */
6240 	      EXECUTE_IF_SET_IN_BITMAP (&check_only_regs, 0, j, bi)
6241 		if (bitmap_bit_p (&live_regs, j))
6242 		  bitmap_set_bit (df_get_live_in (prev_bb), j);
6243 		else
6244 		  bitmap_clear_bit (df_get_live_in (prev_bb), j);
6245 	    }
6246 	  if (curr_bb != last_bb)
6247 	    {
6248 	      /* Update df_get_live_out (curr_bb):  */
6249 	      EXECUTE_IF_SET_IN_BITMAP (&check_only_regs, 0, j, bi)
6250 		{
6251 		  live_p = bitmap_bit_p (&live_regs, j);
6252 		  if (! live_p)
6253 		    FOR_EACH_EDGE (e, ei, curr_bb->succs)
6254 		      if (bitmap_bit_p (df_get_live_in (e->dest), j))
6255 			{
6256 			  live_p = true;
6257 			  break;
6258 			}
6259 		  if (live_p)
6260 		    bitmap_set_bit (df_get_live_out (curr_bb), j);
6261 		  else
6262 		    bitmap_clear_bit (df_get_live_out (curr_bb), j);
6263 		}
6264 	    }
6265 	  prev_bb = curr_bb;
6266 	  bitmap_and (&live_regs, &check_only_regs, df_get_live_out (curr_bb));
6267 	}
6268       if (! NONDEBUG_INSN_P (curr_insn))
6269 	continue;
6270       curr_id = lra_get_insn_recog_data (curr_insn);
6271       curr_static_id = curr_id->insn_static_data;
6272       remove_p = false;
6273       if ((set = single_set (curr_insn)) != NULL_RTX
6274 	  && REG_P (SET_DEST (set))
6275 	  && (regno = REGNO (SET_DEST (set))) >= FIRST_PSEUDO_REGISTER
6276 	  && SET_DEST (set) != pic_offset_table_rtx
6277 	  && bitmap_bit_p (&check_only_regs, regno)
6278 	  && ! bitmap_bit_p (&live_regs, regno))
6279 	remove_p = true;
6280       /* See which defined values die here.  */
6281       for (reg = curr_id->regs; reg != NULL; reg = reg->next)
6282 	if (reg->type == OP_OUT && ! reg->subreg_p)
6283 	  bitmap_clear_bit (&live_regs, reg->regno);
6284       for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next)
6285 	if (reg->type == OP_OUT && ! reg->subreg_p)
6286 	  bitmap_clear_bit (&live_regs, reg->regno);
6287       if (curr_id->arg_hard_regs != NULL)
6288 	/* Make clobbered argument hard registers die.  */
6289 	for (i = 0; (regno = curr_id->arg_hard_regs[i]) >= 0; i++)
6290 	  if (regno >= FIRST_PSEUDO_REGISTER)
6291 	    bitmap_clear_bit (&live_regs, regno - FIRST_PSEUDO_REGISTER);
6292       /* Mark each used value as live.  */
6293       for (reg = curr_id->regs; reg != NULL; reg = reg->next)
6294 	if (reg->type != OP_OUT
6295 	    && bitmap_bit_p (&check_only_regs, reg->regno))
6296 	  bitmap_set_bit (&live_regs, reg->regno);
6297       for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next)
6298 	if (reg->type != OP_OUT
6299 	    && bitmap_bit_p (&check_only_regs, reg->regno))
6300 	  bitmap_set_bit (&live_regs, reg->regno);
6301       if (curr_id->arg_hard_regs != NULL)
6302 	/* Make used argument hard registers live.  */
6303 	for (i = 0; (regno = curr_id->arg_hard_regs[i]) >= 0; i++)
6304 	  if (regno < FIRST_PSEUDO_REGISTER
6305 	      && bitmap_bit_p (&check_only_regs, regno))
6306 	    bitmap_set_bit (&live_regs, regno);
6307       /* It is quite important to remove dead move insns because it
6308 	 means removing dead store.  We don't need to process them for
6309 	 constraints.  */
6310       if (remove_p)
6311 	{
6312 	  if (lra_dump_file != NULL)
6313 	    {
6314 	      fprintf (lra_dump_file, "	    Removing dead insn:\n ");
6315 	      dump_insn_slim (lra_dump_file, curr_insn);
6316 	    }
6317 	  lra_set_insn_deleted (curr_insn);
6318 	}
6319     }
6320 }
6321 
6322 /* The structure describes info to do an inheritance for the current
6323    insn.  We need to collect such info first before doing the
6324    transformations because the transformations change the insn
6325    internal representation.  */
6326 struct to_inherit
6327 {
6328   /* Original regno.  */
6329   int regno;
6330   /* Subsequent insns which can inherit original reg value.  */
6331   rtx insns;
6332 };
6333 
6334 /* Array containing all info for doing inheritance from the current
6335    insn.  */
6336 static struct to_inherit to_inherit[LRA_MAX_INSN_RELOADS];
6337 
6338 /* Number elements in the previous array.  */
6339 static int to_inherit_num;
6340 
6341 /* Add inheritance info REGNO and INSNS. Their meaning is described in
6342    structure to_inherit.  */
6343 static void
add_to_inherit(int regno,rtx insns)6344 add_to_inherit (int regno, rtx insns)
6345 {
6346   int i;
6347 
6348   for (i = 0; i < to_inherit_num; i++)
6349     if (to_inherit[i].regno == regno)
6350       return;
6351   lra_assert (to_inherit_num < LRA_MAX_INSN_RELOADS);
6352   to_inherit[to_inherit_num].regno = regno;
6353   to_inherit[to_inherit_num++].insns = insns;
6354 }
6355 
6356 /* Return the last non-debug insn in basic block BB, or the block begin
6357    note if none.  */
6358 static rtx_insn *
get_last_insertion_point(basic_block bb)6359 get_last_insertion_point (basic_block bb)
6360 {
6361   rtx_insn *insn;
6362 
6363   FOR_BB_INSNS_REVERSE (bb, insn)
6364     if (NONDEBUG_INSN_P (insn) || NOTE_INSN_BASIC_BLOCK_P (insn))
6365       return insn;
6366   gcc_unreachable ();
6367 }
6368 
6369 /* Set up RES by registers living on edges FROM except the edge (FROM,
6370    TO) or by registers set up in a jump insn in BB FROM.  */
6371 static void
get_live_on_other_edges(basic_block from,basic_block to,bitmap res)6372 get_live_on_other_edges (basic_block from, basic_block to, bitmap res)
6373 {
6374   rtx_insn *last;
6375   struct lra_insn_reg *reg;
6376   edge e;
6377   edge_iterator ei;
6378 
6379   lra_assert (to != NULL);
6380   bitmap_clear (res);
6381   FOR_EACH_EDGE (e, ei, from->succs)
6382     if (e->dest != to)
6383       bitmap_ior_into (res, df_get_live_in (e->dest));
6384   last = get_last_insertion_point (from);
6385   if (! JUMP_P (last))
6386     return;
6387   curr_id = lra_get_insn_recog_data (last);
6388   for (reg = curr_id->regs; reg != NULL; reg = reg->next)
6389     if (reg->type != OP_IN)
6390       bitmap_set_bit (res, reg->regno);
6391 }
6392 
6393 /* Used as a temporary results of some bitmap calculations.  */
6394 static bitmap_head temp_bitmap;
6395 
6396 /* We split for reloads of small class of hard regs.  The following
6397    defines how many hard regs the class should have to be qualified as
6398    small.  The code is mostly oriented to x86/x86-64 architecture
6399    where some insns need to use only specific register or pair of
6400    registers and these register can live in RTL explicitly, e.g. for
6401    parameter passing.  */
6402 static const int max_small_class_regs_num = 2;
6403 
6404 /* Do inheritance/split transformations in EBB starting with HEAD and
6405    finishing on TAIL.  We process EBB insns in the reverse order.
6406    Return true if we did any inheritance/split transformation in the
6407    EBB.
6408 
6409    We should avoid excessive splitting which results in worse code
6410    because of inaccurate cost calculations for spilling new split
6411    pseudos in such case.  To achieve this we do splitting only if
6412    register pressure is high in given basic block and there are reload
6413    pseudos requiring hard registers.  We could do more register
6414    pressure calculations at any given program point to avoid necessary
6415    splitting even more but it is to expensive and the current approach
6416    works well enough.  */
6417 static bool
inherit_in_ebb(rtx_insn * head,rtx_insn * tail)6418 inherit_in_ebb (rtx_insn *head, rtx_insn *tail)
6419 {
6420   int i, src_regno, dst_regno, nregs;
6421   bool change_p, succ_p, update_reloads_num_p;
6422   rtx_insn *prev_insn, *last_insn;
6423   rtx next_usage_insns, curr_set;
6424   enum reg_class cl;
6425   struct lra_insn_reg *reg;
6426   basic_block last_processed_bb, curr_bb = NULL;
6427   HARD_REG_SET potential_reload_hard_regs, live_hard_regs;
6428   bitmap to_process;
6429   unsigned int j;
6430   bitmap_iterator bi;
6431   bool head_p, after_p;
6432 
6433   change_p = false;
6434   curr_usage_insns_check++;
6435   clear_invariants ();
6436   reloads_num = calls_num = 0;
6437   for (unsigned int i = 0; i < NUM_ABI_IDS; ++i)
6438     last_call_for_abi[i] = 0;
6439   CLEAR_HARD_REG_SET (full_and_partial_call_clobbers);
6440   bitmap_clear (&check_only_regs);
6441   bitmap_clear (&invalid_invariant_regs);
6442   last_processed_bb = NULL;
6443   CLEAR_HARD_REG_SET (potential_reload_hard_regs);
6444   live_hard_regs = eliminable_regset | lra_no_alloc_regs;
6445   /* We don't process new insns generated in the loop.	*/
6446   for (curr_insn = tail; curr_insn != PREV_INSN (head); curr_insn = prev_insn)
6447     {
6448       prev_insn = PREV_INSN (curr_insn);
6449       if (BLOCK_FOR_INSN (curr_insn) != NULL)
6450 	curr_bb = BLOCK_FOR_INSN (curr_insn);
6451       if (last_processed_bb != curr_bb)
6452 	{
6453 	  /* We are at the end of BB.  Add qualified living
6454 	     pseudos for potential splitting.  */
6455 	  to_process = df_get_live_out (curr_bb);
6456 	  if (last_processed_bb != NULL)
6457 	    {
6458 	      /* We are somewhere in the middle of EBB.	 */
6459 	      get_live_on_other_edges (curr_bb, last_processed_bb,
6460 				       &temp_bitmap);
6461 	      to_process = &temp_bitmap;
6462 	    }
6463 	  last_processed_bb = curr_bb;
6464 	  last_insn = get_last_insertion_point (curr_bb);
6465 	  after_p = (! JUMP_P (last_insn)
6466 		     && (! CALL_P (last_insn)
6467 			 || (find_reg_note (last_insn,
6468 					   REG_NORETURN, NULL_RTX) == NULL_RTX
6469 			     && ! SIBLING_CALL_P (last_insn))));
6470 	  CLEAR_HARD_REG_SET (potential_reload_hard_regs);
6471 	  EXECUTE_IF_SET_IN_BITMAP (to_process, 0, j, bi)
6472 	    {
6473 	      if ((int) j >= lra_constraint_new_regno_start)
6474 		break;
6475 	      if (j < FIRST_PSEUDO_REGISTER || reg_renumber[j] >= 0)
6476 		{
6477 		  if (j < FIRST_PSEUDO_REGISTER)
6478 		    SET_HARD_REG_BIT (live_hard_regs, j);
6479 		  else
6480 		    add_to_hard_reg_set (&live_hard_regs,
6481 					 PSEUDO_REGNO_MODE (j),
6482 					 reg_renumber[j]);
6483 		  setup_next_usage_insn (j, last_insn, reloads_num, after_p);
6484 		}
6485 	    }
6486 	}
6487       src_regno = dst_regno = -1;
6488       curr_set = single_set (curr_insn);
6489       if (curr_set != NULL_RTX && REG_P (SET_DEST (curr_set)))
6490 	dst_regno = REGNO (SET_DEST (curr_set));
6491       if (curr_set != NULL_RTX && REG_P (SET_SRC (curr_set)))
6492 	src_regno = REGNO (SET_SRC (curr_set));
6493       update_reloads_num_p = true;
6494       if (src_regno < lra_constraint_new_regno_start
6495 	  && src_regno >= FIRST_PSEUDO_REGISTER
6496 	  && reg_renumber[src_regno] < 0
6497 	  && dst_regno >= lra_constraint_new_regno_start
6498 	  && (cl = lra_get_allocno_class (dst_regno)) != NO_REGS)
6499 	{
6500 	  /* 'reload_pseudo <- original_pseudo'.  */
6501 	  if (ira_class_hard_regs_num[cl] <= max_small_class_regs_num)
6502 	    reloads_num++;
6503 	  update_reloads_num_p = false;
6504 	  succ_p = false;
6505 	  if (usage_insns[src_regno].check == curr_usage_insns_check
6506 	      && (next_usage_insns = usage_insns[src_regno].insns) != NULL_RTX)
6507 	    succ_p = inherit_reload_reg (false, src_regno, cl,
6508 					 curr_insn, next_usage_insns);
6509 	  if (succ_p)
6510 	    change_p = true;
6511 	  else
6512 	    setup_next_usage_insn (src_regno, curr_insn, reloads_num, false);
6513 	  if (hard_reg_set_subset_p (reg_class_contents[cl], live_hard_regs))
6514 	    potential_reload_hard_regs |= reg_class_contents[cl];
6515 	}
6516       else if (src_regno < 0
6517 	       && dst_regno >= lra_constraint_new_regno_start
6518 	       && invariant_p (SET_SRC (curr_set))
6519 	       && (cl = lra_get_allocno_class (dst_regno)) != NO_REGS
6520 	       && ! bitmap_bit_p (&invalid_invariant_regs, dst_regno)
6521 	       && ! bitmap_bit_p (&invalid_invariant_regs,
6522 				  ORIGINAL_REGNO(regno_reg_rtx[dst_regno])))
6523 	{
6524 	  /* 'reload_pseudo <- invariant'.  */
6525 	  if (ira_class_hard_regs_num[cl] <= max_small_class_regs_num)
6526 	    reloads_num++;
6527 	  update_reloads_num_p = false;
6528 	  if (process_invariant_for_inheritance (SET_DEST (curr_set), SET_SRC (curr_set)))
6529 	    change_p = true;
6530 	  if (hard_reg_set_subset_p (reg_class_contents[cl], live_hard_regs))
6531 	    potential_reload_hard_regs |= reg_class_contents[cl];
6532 	}
6533       else if (src_regno >= lra_constraint_new_regno_start
6534 	       && dst_regno < lra_constraint_new_regno_start
6535 	       && dst_regno >= FIRST_PSEUDO_REGISTER
6536 	       && reg_renumber[dst_regno] < 0
6537 	       && (cl = lra_get_allocno_class (src_regno)) != NO_REGS
6538 	       && usage_insns[dst_regno].check == curr_usage_insns_check
6539 	       && (next_usage_insns
6540 		   = usage_insns[dst_regno].insns) != NULL_RTX)
6541 	{
6542 	  if (ira_class_hard_regs_num[cl] <= max_small_class_regs_num)
6543 	    reloads_num++;
6544 	  update_reloads_num_p = false;
6545 	  /* 'original_pseudo <- reload_pseudo'.  */
6546 	  if (! JUMP_P (curr_insn)
6547 	      && inherit_reload_reg (true, dst_regno, cl,
6548 				     curr_insn, next_usage_insns))
6549 	    change_p = true;
6550 	  /* Invalidate.  */
6551 	  usage_insns[dst_regno].check = 0;
6552 	  if (hard_reg_set_subset_p (reg_class_contents[cl], live_hard_regs))
6553 	    potential_reload_hard_regs |= reg_class_contents[cl];
6554 	}
6555       else if (INSN_P (curr_insn))
6556 	{
6557 	  int iter;
6558 	  int max_uid = get_max_uid ();
6559 
6560 	  curr_id = lra_get_insn_recog_data (curr_insn);
6561 	  curr_static_id = curr_id->insn_static_data;
6562 	  to_inherit_num = 0;
6563 	  /* Process insn definitions.	*/
6564 	  for (iter = 0; iter < 2; iter++)
6565 	    for (reg = iter == 0 ? curr_id->regs : curr_static_id->hard_regs;
6566 		 reg != NULL;
6567 		 reg = reg->next)
6568 	      if (reg->type != OP_IN
6569 		  && (dst_regno = reg->regno) < lra_constraint_new_regno_start)
6570 		{
6571 		  if (dst_regno >= FIRST_PSEUDO_REGISTER && reg->type == OP_OUT
6572 		      && reg_renumber[dst_regno] < 0 && ! reg->subreg_p
6573 		      && usage_insns[dst_regno].check == curr_usage_insns_check
6574 		      && (next_usage_insns
6575 			  = usage_insns[dst_regno].insns) != NULL_RTX)
6576 		    {
6577 		      struct lra_insn_reg *r;
6578 
6579 		      for (r = curr_id->regs; r != NULL; r = r->next)
6580 			if (r->type != OP_OUT && r->regno == dst_regno)
6581 			  break;
6582 		      /* Don't do inheritance if the pseudo is also
6583 			 used in the insn.  */
6584 		      if (r == NULL)
6585 			/* We cannot do inheritance right now
6586 			   because the current insn reg info (chain
6587 			   regs) can change after that.  */
6588 			add_to_inherit (dst_regno, next_usage_insns);
6589 		    }
6590 		  /* We cannot process one reg twice here because of
6591 		     usage_insns invalidation.  */
6592 		  if ((dst_regno < FIRST_PSEUDO_REGISTER
6593 		       || reg_renumber[dst_regno] >= 0)
6594 		      && ! reg->subreg_p && reg->type != OP_IN)
6595 		    {
6596 		      HARD_REG_SET s;
6597 
6598 		      if (split_if_necessary (dst_regno, reg->biggest_mode,
6599 					      potential_reload_hard_regs,
6600 					      false, curr_insn, max_uid))
6601 			change_p = true;
6602 		      CLEAR_HARD_REG_SET (s);
6603 		      if (dst_regno < FIRST_PSEUDO_REGISTER)
6604 			add_to_hard_reg_set (&s, reg->biggest_mode, dst_regno);
6605 		      else
6606 			add_to_hard_reg_set (&s, PSEUDO_REGNO_MODE (dst_regno),
6607 					     reg_renumber[dst_regno]);
6608 		      live_hard_regs &= ~s;
6609 		      potential_reload_hard_regs &= ~s;
6610 		    }
6611 		  /* We should invalidate potential inheritance or
6612 		     splitting for the current insn usages to the next
6613 		     usage insns (see code below) as the output pseudo
6614 		     prevents this.  */
6615 		  if ((dst_regno >= FIRST_PSEUDO_REGISTER
6616 		       && reg_renumber[dst_regno] < 0)
6617 		      || (reg->type == OP_OUT && ! reg->subreg_p
6618 			  && (dst_regno < FIRST_PSEUDO_REGISTER
6619 			      || reg_renumber[dst_regno] >= 0)))
6620 		    {
6621 		      /* Invalidate and mark definitions.  */
6622 		      if (dst_regno >= FIRST_PSEUDO_REGISTER)
6623 			usage_insns[dst_regno].check = -(int) INSN_UID (curr_insn);
6624 		      else
6625 			{
6626 			  nregs = hard_regno_nregs (dst_regno,
6627 						    reg->biggest_mode);
6628 			  for (i = 0; i < nregs; i++)
6629 			    usage_insns[dst_regno + i].check
6630 			      = -(int) INSN_UID (curr_insn);
6631 			}
6632 		    }
6633 		}
6634 	  /* Process clobbered call regs.  */
6635 	  if (curr_id->arg_hard_regs != NULL)
6636 	    for (i = 0; (dst_regno = curr_id->arg_hard_regs[i]) >= 0; i++)
6637 	      if (dst_regno >= FIRST_PSEUDO_REGISTER)
6638 		usage_insns[dst_regno - FIRST_PSEUDO_REGISTER].check
6639 		  = -(int) INSN_UID (curr_insn);
6640 	  if (! JUMP_P (curr_insn))
6641 	    for (i = 0; i < to_inherit_num; i++)
6642 	      if (inherit_reload_reg (true, to_inherit[i].regno,
6643 				      ALL_REGS, curr_insn,
6644 				      to_inherit[i].insns))
6645 	      change_p = true;
6646 	  if (CALL_P (curr_insn))
6647 	    {
6648 	      rtx cheap, pat, dest;
6649 	      rtx_insn *restore;
6650 	      int regno, hard_regno;
6651 
6652 	      calls_num++;
6653 	      function_abi callee_abi = insn_callee_abi (curr_insn);
6654 	      last_call_for_abi[callee_abi.id ()] = calls_num;
6655 	      full_and_partial_call_clobbers
6656 		|= callee_abi.full_and_partial_reg_clobbers ();
6657 	      if ((cheap = find_reg_note (curr_insn,
6658 					  REG_RETURNED, NULL_RTX)) != NULL_RTX
6659 		  && ((cheap = XEXP (cheap, 0)), true)
6660 		  && (regno = REGNO (cheap)) >= FIRST_PSEUDO_REGISTER
6661 		  && (hard_regno = reg_renumber[regno]) >= 0
6662 		  && usage_insns[regno].check == curr_usage_insns_check
6663 		  /* If there are pending saves/restores, the
6664 		     optimization is not worth.	 */
6665 		  && usage_insns[regno].calls_num == calls_num - 1
6666 		  && callee_abi.clobbers_reg_p (GET_MODE (cheap), hard_regno))
6667 		{
6668 		  /* Restore the pseudo from the call result as
6669 		     REG_RETURNED note says that the pseudo value is
6670 		     in the call result and the pseudo is an argument
6671 		     of the call.  */
6672 		  pat = PATTERN (curr_insn);
6673 		  if (GET_CODE (pat) == PARALLEL)
6674 		    pat = XVECEXP (pat, 0, 0);
6675 		  dest = SET_DEST (pat);
6676 		  /* For multiple return values dest is PARALLEL.
6677 		     Currently we handle only single return value case.  */
6678 		  if (REG_P (dest))
6679 		    {
6680 		      start_sequence ();
6681 		      emit_move_insn (cheap, copy_rtx (dest));
6682 		      restore = get_insns ();
6683 		      end_sequence ();
6684 		      lra_process_new_insns (curr_insn, NULL, restore,
6685 					     "Inserting call parameter restore");
6686 		      /* We don't need to save/restore of the pseudo from
6687 			 this call.	 */
6688 		      usage_insns[regno].calls_num = calls_num;
6689 		      remove_from_hard_reg_set
6690 			(&full_and_partial_call_clobbers,
6691 			 GET_MODE (cheap), hard_regno);
6692 		      bitmap_set_bit (&check_only_regs, regno);
6693 		    }
6694 		}
6695 	    }
6696 	  to_inherit_num = 0;
6697 	  /* Process insn usages.  */
6698 	  for (iter = 0; iter < 2; iter++)
6699 	    for (reg = iter == 0 ? curr_id->regs : curr_static_id->hard_regs;
6700 		 reg != NULL;
6701 		 reg = reg->next)
6702 	      if ((reg->type != OP_OUT
6703 		   || (reg->type == OP_OUT && reg->subreg_p))
6704 		  && (src_regno = reg->regno) < lra_constraint_new_regno_start)
6705 		{
6706 		  if (src_regno >= FIRST_PSEUDO_REGISTER
6707 		      && reg_renumber[src_regno] < 0 && reg->type == OP_IN)
6708 		    {
6709 		      if (usage_insns[src_regno].check == curr_usage_insns_check
6710 			  && (next_usage_insns
6711 			      = usage_insns[src_regno].insns) != NULL_RTX
6712 			  && NONDEBUG_INSN_P (curr_insn))
6713 			add_to_inherit (src_regno, next_usage_insns);
6714 		      else if (usage_insns[src_regno].check
6715 			       != -(int) INSN_UID (curr_insn))
6716 			/* Add usages but only if the reg is not set up
6717 			   in the same insn.  */
6718 			add_next_usage_insn (src_regno, curr_insn, reloads_num);
6719 		    }
6720 		  else if (src_regno < FIRST_PSEUDO_REGISTER
6721 			   || reg_renumber[src_regno] >= 0)
6722 		    {
6723 		      bool before_p;
6724 		      rtx_insn *use_insn = curr_insn;
6725 
6726 		      before_p = (JUMP_P (curr_insn)
6727 				  || (CALL_P (curr_insn) && reg->type == OP_IN));
6728 		      if (NONDEBUG_INSN_P (curr_insn)
6729 			  && (! JUMP_P (curr_insn) || reg->type == OP_IN)
6730 			  && split_if_necessary (src_regno, reg->biggest_mode,
6731 						 potential_reload_hard_regs,
6732 						 before_p, curr_insn, max_uid))
6733 			{
6734 			  if (reg->subreg_p)
6735 			    check_and_force_assignment_correctness_p = true;
6736 			  change_p = true;
6737 			  /* Invalidate. */
6738 			  usage_insns[src_regno].check = 0;
6739 			  if (before_p)
6740 			    use_insn = PREV_INSN (curr_insn);
6741 			}
6742 		      if (NONDEBUG_INSN_P (curr_insn))
6743 			{
6744 			  if (src_regno < FIRST_PSEUDO_REGISTER)
6745 			    add_to_hard_reg_set (&live_hard_regs,
6746 						 reg->biggest_mode, src_regno);
6747 			  else
6748 			    add_to_hard_reg_set (&live_hard_regs,
6749 						 PSEUDO_REGNO_MODE (src_regno),
6750 						 reg_renumber[src_regno]);
6751 			}
6752 		      if (src_regno >= FIRST_PSEUDO_REGISTER)
6753 			add_next_usage_insn (src_regno, use_insn, reloads_num);
6754 		      else
6755 			{
6756 			  for (i = 0; i < hard_regno_nregs (src_regno, reg->biggest_mode); i++)
6757 			    add_next_usage_insn (src_regno + i, use_insn, reloads_num);
6758 			}
6759 		    }
6760 		}
6761 	  /* Process used call regs.  */
6762 	  if (curr_id->arg_hard_regs != NULL)
6763 	    for (i = 0; (src_regno = curr_id->arg_hard_regs[i]) >= 0; i++)
6764 	      if (src_regno < FIRST_PSEUDO_REGISTER)
6765 		{
6766 	           SET_HARD_REG_BIT (live_hard_regs, src_regno);
6767 	           add_next_usage_insn (src_regno, curr_insn, reloads_num);
6768 		}
6769 	  for (i = 0; i < to_inherit_num; i++)
6770 	    {
6771 	      src_regno = to_inherit[i].regno;
6772 	      if (inherit_reload_reg (false, src_regno, ALL_REGS,
6773 				      curr_insn, to_inherit[i].insns))
6774 		change_p = true;
6775 	      else
6776 		setup_next_usage_insn (src_regno, curr_insn, reloads_num, false);
6777 	    }
6778 	}
6779       if (update_reloads_num_p
6780 	  && NONDEBUG_INSN_P (curr_insn) && curr_set != NULL_RTX)
6781 	{
6782 	  int regno = -1;
6783 	  if ((REG_P (SET_DEST (curr_set))
6784 	       && (regno = REGNO (SET_DEST (curr_set))) >= lra_constraint_new_regno_start
6785 	       && reg_renumber[regno] < 0
6786 	       && (cl = lra_get_allocno_class (regno)) != NO_REGS)
6787 	      || (REG_P (SET_SRC (curr_set))
6788 	          && (regno = REGNO (SET_SRC (curr_set))) >= lra_constraint_new_regno_start
6789 	          && reg_renumber[regno] < 0
6790 	          && (cl = lra_get_allocno_class (regno)) != NO_REGS))
6791 	    {
6792 	      if (ira_class_hard_regs_num[cl] <= max_small_class_regs_num)
6793 		reloads_num++;
6794 	      if (hard_reg_set_subset_p (reg_class_contents[cl], live_hard_regs))
6795 		potential_reload_hard_regs |= reg_class_contents[cl];
6796 	    }
6797 	}
6798       if (NONDEBUG_INSN_P (curr_insn))
6799 	{
6800 	  int regno;
6801 
6802 	  /* Invalidate invariants with changed regs.  */
6803 	  curr_id = lra_get_insn_recog_data (curr_insn);
6804 	  for (reg = curr_id->regs; reg != NULL; reg = reg->next)
6805 	    if (reg->type != OP_IN)
6806 	      {
6807 		bitmap_set_bit (&invalid_invariant_regs, reg->regno);
6808 		bitmap_set_bit (&invalid_invariant_regs,
6809 				ORIGINAL_REGNO (regno_reg_rtx[reg->regno]));
6810 	      }
6811 	  curr_static_id = curr_id->insn_static_data;
6812 	  for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next)
6813 	    if (reg->type != OP_IN)
6814 	      bitmap_set_bit (&invalid_invariant_regs, reg->regno);
6815 	  if (curr_id->arg_hard_regs != NULL)
6816 	    for (i = 0; (regno = curr_id->arg_hard_regs[i]) >= 0; i++)
6817 	      if (regno >= FIRST_PSEUDO_REGISTER)
6818 		bitmap_set_bit (&invalid_invariant_regs,
6819 				regno - FIRST_PSEUDO_REGISTER);
6820 	}
6821       /* We reached the start of the current basic block.  */
6822       if (prev_insn == NULL_RTX || prev_insn == PREV_INSN (head)
6823 	  || BLOCK_FOR_INSN (prev_insn) != curr_bb)
6824 	{
6825 	  /* We reached the beginning of the current block -- do
6826 	     rest of spliting in the current BB.  */
6827 	  to_process = df_get_live_in (curr_bb);
6828 	  if (BLOCK_FOR_INSN (head) != curr_bb)
6829 	    {
6830 	      /* We are somewhere in the middle of EBB.	 */
6831 	      get_live_on_other_edges (EDGE_PRED (curr_bb, 0)->src,
6832 				       curr_bb, &temp_bitmap);
6833 	      to_process = &temp_bitmap;
6834 	    }
6835 	  head_p = true;
6836 	  EXECUTE_IF_SET_IN_BITMAP (to_process, 0, j, bi)
6837 	    {
6838 	      if ((int) j >= lra_constraint_new_regno_start)
6839 		break;
6840 	      if (((int) j < FIRST_PSEUDO_REGISTER || reg_renumber[j] >= 0)
6841 		  && usage_insns[j].check == curr_usage_insns_check
6842 		  && (next_usage_insns = usage_insns[j].insns) != NULL_RTX)
6843 		{
6844 		  if (need_for_split_p (potential_reload_hard_regs, j))
6845 		    {
6846 		      if (lra_dump_file != NULL && head_p)
6847 			{
6848 			  fprintf (lra_dump_file,
6849 				   "  ----------------------------------\n");
6850 			  head_p = false;
6851 			}
6852 		      if (split_reg (false, j, bb_note (curr_bb),
6853 				     next_usage_insns, NULL))
6854 			change_p = true;
6855 		    }
6856 		  usage_insns[j].check = 0;
6857 		}
6858 	    }
6859 	}
6860     }
6861   return change_p;
6862 }
6863 
6864 /* This value affects EBB forming.  If probability of edge from EBB to
6865    a BB is not greater than the following value, we don't add the BB
6866    to EBB.  */
6867 #define EBB_PROBABILITY_CUTOFF \
6868   ((REG_BR_PROB_BASE * param_lra_inheritance_ebb_probability_cutoff) / 100)
6869 
6870 /* Current number of inheritance/split iteration.  */
6871 int lra_inheritance_iter;
6872 
6873 /* Entry function for inheritance/split pass.  */
6874 void
lra_inheritance(void)6875 lra_inheritance (void)
6876 {
6877   int i;
6878   basic_block bb, start_bb;
6879   edge e;
6880 
6881   lra_inheritance_iter++;
6882   if (lra_inheritance_iter > LRA_MAX_INHERITANCE_PASSES)
6883     return;
6884   timevar_push (TV_LRA_INHERITANCE);
6885   if (lra_dump_file != NULL)
6886     fprintf (lra_dump_file, "\n********** Inheritance #%d: **********\n\n",
6887 	     lra_inheritance_iter);
6888   curr_usage_insns_check = 0;
6889   usage_insns = XNEWVEC (struct usage_insns, lra_constraint_new_regno_start);
6890   for (i = 0; i < lra_constraint_new_regno_start; i++)
6891     usage_insns[i].check = 0;
6892   bitmap_initialize (&check_only_regs, &reg_obstack);
6893   bitmap_initialize (&invalid_invariant_regs, &reg_obstack);
6894   bitmap_initialize (&live_regs, &reg_obstack);
6895   bitmap_initialize (&temp_bitmap, &reg_obstack);
6896   bitmap_initialize (&ebb_global_regs, &reg_obstack);
6897   FOR_EACH_BB_FN (bb, cfun)
6898     {
6899       start_bb = bb;
6900       if (lra_dump_file != NULL)
6901 	fprintf (lra_dump_file, "EBB");
6902       /* Form a EBB starting with BB.  */
6903       bitmap_clear (&ebb_global_regs);
6904       bitmap_ior_into (&ebb_global_regs, df_get_live_in (bb));
6905       for (;;)
6906 	{
6907 	  if (lra_dump_file != NULL)
6908 	    fprintf (lra_dump_file, " %d", bb->index);
6909 	  if (bb->next_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)
6910 	      || LABEL_P (BB_HEAD (bb->next_bb)))
6911 	    break;
6912 	  e = find_fallthru_edge (bb->succs);
6913 	  if (! e)
6914 	    break;
6915 	  if (e->probability.initialized_p ()
6916 	      && e->probability.to_reg_br_prob_base () < EBB_PROBABILITY_CUTOFF)
6917 	    break;
6918 	  bb = bb->next_bb;
6919 	}
6920       bitmap_ior_into (&ebb_global_regs, df_get_live_out (bb));
6921       if (lra_dump_file != NULL)
6922 	fprintf (lra_dump_file, "\n");
6923       if (inherit_in_ebb (BB_HEAD (start_bb), BB_END (bb)))
6924 	/* Remember that the EBB head and tail can change in
6925 	   inherit_in_ebb.  */
6926 	update_ebb_live_info (BB_HEAD (start_bb), BB_END (bb));
6927     }
6928   bitmap_release (&ebb_global_regs);
6929   bitmap_release (&temp_bitmap);
6930   bitmap_release (&live_regs);
6931   bitmap_release (&invalid_invariant_regs);
6932   bitmap_release (&check_only_regs);
6933   free (usage_insns);
6934 
6935   timevar_pop (TV_LRA_INHERITANCE);
6936 }
6937 
6938 
6939 
6940 /* This page contains code to undo failed inheritance/split
6941    transformations.  */
6942 
6943 /* Current number of iteration undoing inheritance/split.  */
6944 int lra_undo_inheritance_iter;
6945 
6946 /* Fix BB live info LIVE after removing pseudos created on pass doing
6947    inheritance/split which are REMOVED_PSEUDOS.	 */
6948 static void
fix_bb_live_info(bitmap live,bitmap removed_pseudos)6949 fix_bb_live_info (bitmap live, bitmap removed_pseudos)
6950 {
6951   unsigned int regno;
6952   bitmap_iterator bi;
6953 
6954   EXECUTE_IF_SET_IN_BITMAP (removed_pseudos, 0, regno, bi)
6955     if (bitmap_clear_bit (live, regno)
6956 	&& REG_P (lra_reg_info[regno].restore_rtx))
6957       bitmap_set_bit (live, REGNO (lra_reg_info[regno].restore_rtx));
6958 }
6959 
6960 /* Return regno of the (subreg of) REG. Otherwise, return a negative
6961    number.  */
6962 static int
get_regno(rtx reg)6963 get_regno (rtx reg)
6964 {
6965   if (GET_CODE (reg) == SUBREG)
6966     reg = SUBREG_REG (reg);
6967   if (REG_P (reg))
6968     return REGNO (reg);
6969   return -1;
6970 }
6971 
6972 /* Delete a move INSN with destination reg DREGNO and a previous
6973    clobber insn with the same regno.  The inheritance/split code can
6974    generate moves with preceding clobber and when we delete such moves
6975    we should delete the clobber insn too to keep the correct life
6976    info.  */
6977 static void
delete_move_and_clobber(rtx_insn * insn,int dregno)6978 delete_move_and_clobber (rtx_insn *insn, int dregno)
6979 {
6980   rtx_insn *prev_insn = PREV_INSN (insn);
6981 
6982   lra_set_insn_deleted (insn);
6983   lra_assert (dregno >= 0);
6984   if (prev_insn != NULL && NONDEBUG_INSN_P (prev_insn)
6985       && GET_CODE (PATTERN (prev_insn)) == CLOBBER
6986       && dregno == get_regno (XEXP (PATTERN (prev_insn), 0)))
6987     lra_set_insn_deleted (prev_insn);
6988 }
6989 
6990 /* Remove inheritance/split pseudos which are in REMOVE_PSEUDOS and
6991    return true if we did any change.  The undo transformations for
6992    inheritance looks like
6993       i <- i2
6994       p <- i	  =>   p <- i2
6995    or removing
6996       p <- i, i <- p, and i <- i3
6997    where p is original pseudo from which inheritance pseudo i was
6998    created, i and i3 are removed inheritance pseudos, i2 is another
6999    not removed inheritance pseudo.  All split pseudos or other
7000    occurrences of removed inheritance pseudos are changed on the
7001    corresponding original pseudos.
7002 
7003    The function also schedules insns changed and created during
7004    inheritance/split pass for processing by the subsequent constraint
7005    pass.  */
7006 static bool
remove_inheritance_pseudos(bitmap remove_pseudos)7007 remove_inheritance_pseudos (bitmap remove_pseudos)
7008 {
7009   basic_block bb;
7010   int regno, sregno, prev_sregno, dregno;
7011   rtx restore_rtx;
7012   rtx set, prev_set;
7013   rtx_insn *prev_insn;
7014   bool change_p, done_p;
7015 
7016   change_p = ! bitmap_empty_p (remove_pseudos);
7017   /* We cannot finish the function right away if CHANGE_P is true
7018      because we need to marks insns affected by previous
7019      inheritance/split pass for processing by the subsequent
7020      constraint pass.  */
7021   FOR_EACH_BB_FN (bb, cfun)
7022     {
7023       fix_bb_live_info (df_get_live_in (bb), remove_pseudos);
7024       fix_bb_live_info (df_get_live_out (bb), remove_pseudos);
7025       FOR_BB_INSNS_REVERSE (bb, curr_insn)
7026 	{
7027 	  if (! INSN_P (curr_insn))
7028 	    continue;
7029 	  done_p = false;
7030 	  sregno = dregno = -1;
7031 	  if (change_p && NONDEBUG_INSN_P (curr_insn)
7032 	      && (set = single_set (curr_insn)) != NULL_RTX)
7033 	    {
7034 	      dregno = get_regno (SET_DEST (set));
7035 	      sregno = get_regno (SET_SRC (set));
7036 	    }
7037 
7038 	  if (sregno >= 0 && dregno >= 0)
7039 	    {
7040 	      if (bitmap_bit_p (remove_pseudos, dregno)
7041 		  && ! REG_P (lra_reg_info[dregno].restore_rtx))
7042 		{
7043 		  /* invariant inheritance pseudo <- original pseudo */
7044 		  if (lra_dump_file != NULL)
7045 		    {
7046 		      fprintf (lra_dump_file, "	   Removing invariant inheritance:\n");
7047 		      dump_insn_slim (lra_dump_file, curr_insn);
7048 		      fprintf (lra_dump_file, "\n");
7049 		    }
7050 		  delete_move_and_clobber (curr_insn, dregno);
7051 		  done_p = true;
7052 		}
7053 	      else if (bitmap_bit_p (remove_pseudos, sregno)
7054 		       && ! REG_P (lra_reg_info[sregno].restore_rtx))
7055 		{
7056 		  /* reload pseudo <- invariant inheritance pseudo */
7057 		  start_sequence ();
7058 		  /* We cannot just change the source.  It might be
7059 		     an insn different from the move.  */
7060 		  emit_insn (lra_reg_info[sregno].restore_rtx);
7061 		  rtx_insn *new_insns = get_insns ();
7062 		  end_sequence ();
7063 		  lra_assert (single_set (new_insns) != NULL
7064 			      && SET_DEST (set) == SET_DEST (single_set (new_insns)));
7065 		  lra_process_new_insns (curr_insn, NULL, new_insns,
7066 					 "Changing reload<-invariant inheritance");
7067 		  delete_move_and_clobber (curr_insn, dregno);
7068 		  done_p = true;
7069 		}
7070 	      else if ((bitmap_bit_p (remove_pseudos, sregno)
7071 			&& (get_regno (lra_reg_info[sregno].restore_rtx) == dregno
7072 			    || (bitmap_bit_p (remove_pseudos, dregno)
7073 				&& get_regno (lra_reg_info[sregno].restore_rtx) >= 0
7074 				&& (get_regno (lra_reg_info[sregno].restore_rtx)
7075 				    == get_regno (lra_reg_info[dregno].restore_rtx)))))
7076 		       || (bitmap_bit_p (remove_pseudos, dregno)
7077 			   && get_regno (lra_reg_info[dregno].restore_rtx) == sregno))
7078 		/* One of the following cases:
7079 		     original <- removed inheritance pseudo
7080 		     removed inherit pseudo <- another removed inherit pseudo
7081 		     removed inherit pseudo <- original pseudo
7082 		   Or
7083 		     removed_split_pseudo <- original_reg
7084 		     original_reg <- removed_split_pseudo */
7085 		{
7086 		  if (lra_dump_file != NULL)
7087 		    {
7088 		      fprintf (lra_dump_file, "	   Removing %s:\n",
7089 			       bitmap_bit_p (&lra_split_regs, sregno)
7090 			       || bitmap_bit_p (&lra_split_regs, dregno)
7091 			       ? "split" : "inheritance");
7092 		      dump_insn_slim (lra_dump_file, curr_insn);
7093 		    }
7094 		  delete_move_and_clobber (curr_insn, dregno);
7095 		  done_p = true;
7096 		}
7097 	      else if (bitmap_bit_p (remove_pseudos, sregno)
7098 		       && bitmap_bit_p (&lra_inheritance_pseudos, sregno))
7099 		{
7100 		  /* Search the following pattern:
7101 		       inherit_or_split_pseudo1 <- inherit_or_split_pseudo2
7102 		       original_pseudo <- inherit_or_split_pseudo1
7103 		    where the 2nd insn is the current insn and
7104 		    inherit_or_split_pseudo2 is not removed.  If it is found,
7105 		    change the current insn onto:
7106 		       original_pseudo <- inherit_or_split_pseudo2.  */
7107 		  for (prev_insn = PREV_INSN (curr_insn);
7108 		       prev_insn != NULL_RTX && ! NONDEBUG_INSN_P (prev_insn);
7109 		       prev_insn = PREV_INSN (prev_insn))
7110 		    ;
7111 		  if (prev_insn != NULL_RTX && BLOCK_FOR_INSN (prev_insn) == bb
7112 		      && (prev_set = single_set (prev_insn)) != NULL_RTX
7113 		      /* There should be no subregs in insn we are
7114 			 searching because only the original reg might
7115 			 be in subreg when we changed the mode of
7116 			 load/store for splitting.  */
7117 		      && REG_P (SET_DEST (prev_set))
7118 		      && REG_P (SET_SRC (prev_set))
7119 		      && (int) REGNO (SET_DEST (prev_set)) == sregno
7120 		      && ((prev_sregno = REGNO (SET_SRC (prev_set)))
7121 			  >= FIRST_PSEUDO_REGISTER)
7122 		      && (lra_reg_info[prev_sregno].restore_rtx == NULL_RTX
7123 			  ||
7124 			  /* As we consider chain of inheritance or
7125 			     splitting described in above comment we should
7126 			     check that sregno and prev_sregno were
7127 			     inheritance/split pseudos created from the
7128 			     same original regno.  */
7129 			  (get_regno (lra_reg_info[sregno].restore_rtx) >= 0
7130 			   && (get_regno (lra_reg_info[sregno].restore_rtx)
7131 			       == get_regno (lra_reg_info[prev_sregno].restore_rtx))))
7132 		      && ! bitmap_bit_p (remove_pseudos, prev_sregno))
7133 		    {
7134 		      lra_assert (GET_MODE (SET_SRC (prev_set))
7135 				  == GET_MODE (regno_reg_rtx[sregno]));
7136 		      /* Although we have a single set, the insn can
7137 			 contain more one sregno register occurrence
7138 			 as a source.  Change all occurrences.  */
7139 		      lra_substitute_pseudo_within_insn (curr_insn, sregno,
7140 							 SET_SRC (prev_set),
7141 							 false);
7142 		      /* As we are finishing with processing the insn
7143 			 here, check the destination too as it might
7144 			 inheritance pseudo for another pseudo.  */
7145 		      if (bitmap_bit_p (remove_pseudos, dregno)
7146 			  && bitmap_bit_p (&lra_inheritance_pseudos, dregno)
7147 			  && (restore_rtx
7148 			      = lra_reg_info[dregno].restore_rtx) != NULL_RTX)
7149 			{
7150 			  if (GET_CODE (SET_DEST (set)) == SUBREG)
7151 			    SUBREG_REG (SET_DEST (set)) = restore_rtx;
7152 			  else
7153 			    SET_DEST (set) = restore_rtx;
7154 			}
7155 		      lra_push_insn_and_update_insn_regno_info (curr_insn);
7156 		      lra_set_used_insn_alternative_by_uid
7157 			(INSN_UID (curr_insn), LRA_UNKNOWN_ALT);
7158 		      done_p = true;
7159 		      if (lra_dump_file != NULL)
7160 			{
7161 			  fprintf (lra_dump_file, "    Change reload insn:\n");
7162 			  dump_insn_slim (lra_dump_file, curr_insn);
7163 			}
7164 		    }
7165 		}
7166 	    }
7167 	  if (! done_p)
7168 	    {
7169 	      struct lra_insn_reg *reg;
7170 	      bool restored_regs_p = false;
7171 	      bool kept_regs_p = false;
7172 
7173 	      curr_id = lra_get_insn_recog_data (curr_insn);
7174 	      for (reg = curr_id->regs; reg != NULL; reg = reg->next)
7175 		{
7176 		  regno = reg->regno;
7177 		  restore_rtx = lra_reg_info[regno].restore_rtx;
7178 		  if (restore_rtx != NULL_RTX)
7179 		    {
7180 		      if (change_p && bitmap_bit_p (remove_pseudos, regno))
7181 			{
7182 			  lra_substitute_pseudo_within_insn
7183 			    (curr_insn, regno, restore_rtx, false);
7184 			  restored_regs_p = true;
7185 			}
7186 		      else
7187 			kept_regs_p = true;
7188 		    }
7189 		}
7190 	      if (NONDEBUG_INSN_P (curr_insn) && kept_regs_p)
7191 		{
7192 		  /* The instruction has changed since the previous
7193 		     constraints pass.  */
7194 		  lra_push_insn_and_update_insn_regno_info (curr_insn);
7195 		  lra_set_used_insn_alternative_by_uid
7196 		    (INSN_UID (curr_insn), LRA_UNKNOWN_ALT);
7197 		}
7198 	      else if (restored_regs_p)
7199 		/* The instruction has been restored to the form that
7200 		   it had during the previous constraints pass.  */
7201 		lra_update_insn_regno_info (curr_insn);
7202 	      if (restored_regs_p && lra_dump_file != NULL)
7203 		{
7204 		  fprintf (lra_dump_file, "   Insn after restoring regs:\n");
7205 		  dump_insn_slim (lra_dump_file, curr_insn);
7206 		}
7207 	    }
7208 	}
7209     }
7210   return change_p;
7211 }
7212 
7213 /* If optional reload pseudos failed to get a hard register or was not
7214    inherited, it is better to remove optional reloads.  We do this
7215    transformation after undoing inheritance to figure out necessity to
7216    remove optional reloads easier.  Return true if we do any
7217    change.  */
7218 static bool
undo_optional_reloads(void)7219 undo_optional_reloads (void)
7220 {
7221   bool change_p, keep_p;
7222   unsigned int regno, uid;
7223   bitmap_iterator bi, bi2;
7224   rtx_insn *insn;
7225   rtx set, src, dest;
7226   auto_bitmap removed_optional_reload_pseudos (&reg_obstack);
7227 
7228   bitmap_copy (removed_optional_reload_pseudos, &lra_optional_reload_pseudos);
7229   EXECUTE_IF_SET_IN_BITMAP (&lra_optional_reload_pseudos, 0, regno, bi)
7230     {
7231       keep_p = false;
7232       /* Keep optional reloads from previous subpasses.  */
7233       if (lra_reg_info[regno].restore_rtx == NULL_RTX
7234 	  /* If the original pseudo changed its allocation, just
7235 	     removing the optional pseudo is dangerous as the original
7236 	     pseudo will have longer live range.  */
7237 	  || reg_renumber[REGNO (lra_reg_info[regno].restore_rtx)] >= 0)
7238 	keep_p = true;
7239       else if (reg_renumber[regno] >= 0)
7240 	EXECUTE_IF_SET_IN_BITMAP (&lra_reg_info[regno].insn_bitmap, 0, uid, bi2)
7241 	  {
7242 	    insn = lra_insn_recog_data[uid]->insn;
7243 	    if ((set = single_set (insn)) == NULL_RTX)
7244 	      continue;
7245 	    src = SET_SRC (set);
7246 	    dest = SET_DEST (set);
7247 	    if (! REG_P (src) || ! REG_P (dest))
7248 	      continue;
7249 	    if (REGNO (dest) == regno
7250 		/* Ignore insn for optional reloads itself.  */
7251 		&& REGNO (lra_reg_info[regno].restore_rtx) != REGNO (src)
7252 		/* Check only inheritance on last inheritance pass.  */
7253 		&& (int) REGNO (src) >= new_regno_start
7254 		/* Check that the optional reload was inherited.  */
7255 		&& bitmap_bit_p (&lra_inheritance_pseudos, REGNO (src)))
7256 	      {
7257 		keep_p = true;
7258 		break;
7259 	      }
7260 	  }
7261       if (keep_p)
7262 	{
7263 	  bitmap_clear_bit (removed_optional_reload_pseudos, regno);
7264 	  if (lra_dump_file != NULL)
7265 	    fprintf (lra_dump_file, "Keep optional reload reg %d\n", regno);
7266 	}
7267     }
7268   change_p = ! bitmap_empty_p (removed_optional_reload_pseudos);
7269   auto_bitmap insn_bitmap (&reg_obstack);
7270   EXECUTE_IF_SET_IN_BITMAP (removed_optional_reload_pseudos, 0, regno, bi)
7271     {
7272       if (lra_dump_file != NULL)
7273 	fprintf (lra_dump_file, "Remove optional reload reg %d\n", regno);
7274       bitmap_copy (insn_bitmap, &lra_reg_info[regno].insn_bitmap);
7275       EXECUTE_IF_SET_IN_BITMAP (insn_bitmap, 0, uid, bi2)
7276 	{
7277 	  insn = lra_insn_recog_data[uid]->insn;
7278 	  if ((set = single_set (insn)) != NULL_RTX)
7279 	    {
7280 	      src = SET_SRC (set);
7281 	      dest = SET_DEST (set);
7282 	      if (REG_P (src) && REG_P (dest)
7283 		  && ((REGNO (src) == regno
7284 		       && (REGNO (lra_reg_info[regno].restore_rtx)
7285 			   == REGNO (dest)))
7286 		      || (REGNO (dest) == regno
7287 			  && (REGNO (lra_reg_info[regno].restore_rtx)
7288 			      == REGNO (src)))))
7289 		{
7290 		  if (lra_dump_file != NULL)
7291 		    {
7292 		      fprintf (lra_dump_file, "  Deleting move %u\n",
7293 			       INSN_UID (insn));
7294 		      dump_insn_slim (lra_dump_file, insn);
7295 		    }
7296 		  delete_move_and_clobber (insn, REGNO (dest));
7297 		  continue;
7298 		}
7299 	      /* We should not worry about generation memory-memory
7300 		 moves here as if the corresponding inheritance did
7301 		 not work (inheritance pseudo did not get a hard reg),
7302 		 we remove the inheritance pseudo and the optional
7303 		 reload.  */
7304 	    }
7305 	  lra_substitute_pseudo_within_insn
7306 	    (insn, regno, lra_reg_info[regno].restore_rtx, false);
7307 	  lra_update_insn_regno_info (insn);
7308 	  if (lra_dump_file != NULL)
7309 	    {
7310 	      fprintf (lra_dump_file,
7311 		       "  Restoring original insn:\n");
7312 	      dump_insn_slim (lra_dump_file, insn);
7313 	    }
7314 	}
7315     }
7316   /* Clear restore_regnos.  */
7317   EXECUTE_IF_SET_IN_BITMAP (&lra_optional_reload_pseudos, 0, regno, bi)
7318     lra_reg_info[regno].restore_rtx = NULL_RTX;
7319   return change_p;
7320 }
7321 
7322 /* Entry function for undoing inheritance/split transformation.	 Return true
7323    if we did any RTL change in this pass.  */
7324 bool
lra_undo_inheritance(void)7325 lra_undo_inheritance (void)
7326 {
7327   unsigned int regno;
7328   int hard_regno;
7329   int n_all_inherit, n_inherit, n_all_split, n_split;
7330   rtx restore_rtx;
7331   bitmap_iterator bi;
7332   bool change_p;
7333 
7334   lra_undo_inheritance_iter++;
7335   if (lra_undo_inheritance_iter > LRA_MAX_INHERITANCE_PASSES)
7336     return false;
7337   if (lra_dump_file != NULL)
7338     fprintf (lra_dump_file,
7339 	     "\n********** Undoing inheritance #%d: **********\n\n",
7340 	     lra_undo_inheritance_iter);
7341   auto_bitmap remove_pseudos (&reg_obstack);
7342   n_inherit = n_all_inherit = 0;
7343   EXECUTE_IF_SET_IN_BITMAP (&lra_inheritance_pseudos, 0, regno, bi)
7344     if (lra_reg_info[regno].restore_rtx != NULL_RTX)
7345       {
7346 	n_all_inherit++;
7347 	if (reg_renumber[regno] < 0
7348 	    /* If the original pseudo changed its allocation, just
7349 	       removing inheritance is dangerous as for changing
7350 	       allocation we used shorter live-ranges.  */
7351 	    && (! REG_P (lra_reg_info[regno].restore_rtx)
7352 		|| reg_renumber[REGNO (lra_reg_info[regno].restore_rtx)] < 0))
7353 	  bitmap_set_bit (remove_pseudos, regno);
7354 	else
7355 	  n_inherit++;
7356       }
7357   if (lra_dump_file != NULL && n_all_inherit != 0)
7358     fprintf (lra_dump_file, "Inherit %d out of %d (%.2f%%)\n",
7359 	     n_inherit, n_all_inherit,
7360 	     (double) n_inherit / n_all_inherit * 100);
7361   n_split = n_all_split = 0;
7362   EXECUTE_IF_SET_IN_BITMAP (&lra_split_regs, 0, regno, bi)
7363     if ((restore_rtx = lra_reg_info[regno].restore_rtx) != NULL_RTX)
7364       {
7365 	int restore_regno = REGNO (restore_rtx);
7366 
7367 	n_all_split++;
7368 	hard_regno = (restore_regno >= FIRST_PSEUDO_REGISTER
7369 		      ? reg_renumber[restore_regno] : restore_regno);
7370 	if (hard_regno < 0 || reg_renumber[regno] == hard_regno)
7371 	  bitmap_set_bit (remove_pseudos, regno);
7372 	else
7373 	  {
7374 	    n_split++;
7375 	    if (lra_dump_file != NULL)
7376 	      fprintf (lra_dump_file, "	     Keep split r%d (orig=r%d)\n",
7377 		       regno, restore_regno);
7378 	  }
7379       }
7380   if (lra_dump_file != NULL && n_all_split != 0)
7381     fprintf (lra_dump_file, "Split %d out of %d (%.2f%%)\n",
7382 	     n_split, n_all_split,
7383 	     (double) n_split / n_all_split * 100);
7384   change_p = remove_inheritance_pseudos (remove_pseudos);
7385   /* Clear restore_regnos.  */
7386   EXECUTE_IF_SET_IN_BITMAP (&lra_inheritance_pseudos, 0, regno, bi)
7387     lra_reg_info[regno].restore_rtx = NULL_RTX;
7388   EXECUTE_IF_SET_IN_BITMAP (&lra_split_regs, 0, regno, bi)
7389     lra_reg_info[regno].restore_rtx = NULL_RTX;
7390   change_p = undo_optional_reloads () || change_p;
7391   return change_p;
7392 }
7393