Branch data Line data Source code
1 : : /* Change pseudos by memory.
2 : : Copyright (C) 2010-2024 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 a pass to change spilled pseudos into
23 : : memory.
24 : :
25 : : The pass creates necessary stack slots and assigns spilled pseudos
26 : : to the stack slots in following way:
27 : :
28 : : for all spilled pseudos P most frequently used first do
29 : : for all stack slots S do
30 : : if P doesn't conflict with pseudos assigned to S then
31 : : assign S to P and goto to the next pseudo process
32 : : end
33 : : end
34 : : create new stack slot S and assign P to S
35 : : end
36 : :
37 : : The actual algorithm is bit more complicated because of different
38 : : pseudo sizes.
39 : :
40 : : After that the code changes spilled pseudos (except ones created
41 : : from scratches) by corresponding stack slot memory in RTL.
42 : :
43 : : If at least one stack slot was created, we need to run more passes
44 : : because we have new addresses which should be checked and because
45 : : the old address displacements might change and address constraints
46 : : (or insn memory constraints) might not be satisfied any more.
47 : :
48 : : For some targets, the pass can spill some pseudos into hard
49 : : registers of different class (usually into vector registers)
50 : : instead of spilling them into memory if it is possible and
51 : : profitable. Spilling GENERAL_REGS pseudo into SSE registers for
52 : : Intel Corei7 is an example of such optimization. And this is
53 : : actually recommended by Intel optimization guide.
54 : :
55 : : The file also contains code for final change of pseudos on hard
56 : : regs correspondingly assigned to them. */
57 : :
58 : : #include "config.h"
59 : : #include "system.h"
60 : : #include "coretypes.h"
61 : : #include "backend.h"
62 : : #include "target.h"
63 : : #include "rtl.h"
64 : : #include "df.h"
65 : : #include "insn-config.h"
66 : : #include "regs.h"
67 : : #include "memmodel.h"
68 : : #include "ira.h"
69 : : #include "recog.h"
70 : : #include "output.h"
71 : : #include "cfgrtl.h"
72 : : #include "lra.h"
73 : : #include "lra-int.h"
74 : :
75 : :
76 : : /* Max regno at the start of the pass. */
77 : : static int regs_num;
78 : :
79 : : /* Map spilled regno -> hard regno used instead of memory for
80 : : spilling. */
81 : : static rtx *spill_hard_reg;
82 : :
83 : : /* The structure describes stack slot of a spilled pseudo. */
84 : : struct pseudo_slot
85 : : {
86 : : /* Number (0, 1, ...) of the stack slot to which given pseudo
87 : : belongs. */
88 : : int slot_num;
89 : : /* First or next slot with the same slot number. */
90 : : struct pseudo_slot *next, *first;
91 : : /* Memory representing the spilled pseudo. */
92 : : rtx mem;
93 : : };
94 : :
95 : : /* The stack slots for each spilled pseudo. Indexed by regnos. */
96 : : static struct pseudo_slot *pseudo_slots;
97 : :
98 : : /* The structure describes a register or a stack slot which can be
99 : : used for several spilled pseudos. */
100 : : class slot
101 : : {
102 : : public:
103 : : /* First pseudo with given stack slot. */
104 : : int regno;
105 : : /* Hard reg into which the slot pseudos are spilled. The value is
106 : : negative for pseudos spilled into memory. */
107 : : int hard_regno;
108 : : /* Maximum alignment required by all users of the slot. */
109 : : unsigned int align;
110 : : /* Maximum size required by all users of the slot. */
111 : : poly_int64 size;
112 : : /* Memory representing the all stack slot. It can be different from
113 : : memory representing a pseudo belonging to give stack slot because
114 : : pseudo can be placed in a part of the corresponding stack slot.
115 : : The value is NULL for pseudos spilled into a hard reg. */
116 : : rtx mem;
117 : : /* Combined live ranges of all pseudos belonging to given slot. It
118 : : is used to figure out that a new spilled pseudo can use given
119 : : stack slot. */
120 : : lra_live_range_t live_ranges;
121 : : };
122 : :
123 : : /* Array containing info about the stack slots. The array element is
124 : : indexed by the stack slot number in the range [0..slots_num). */
125 : : static class slot *slots;
126 : : /* The number of the stack slots currently existing. */
127 : : static int slots_num;
128 : :
129 : : /* Set up memory of the spilled pseudo I. The function can allocate
130 : : the corresponding stack slot if it is not done yet. */
131 : : static void
132 : 1421750 : assign_mem_slot (int i)
133 : : {
134 : 1421750 : rtx x = NULL_RTX;
135 : 1421750 : machine_mode mode = GET_MODE (regno_reg_rtx[i]);
136 : 2843500 : poly_int64 inherent_size = PSEUDO_REGNO_BYTES (i);
137 : 1421750 : machine_mode wider_mode
138 : 1421750 : = wider_subreg_mode (mode, lra_reg_info[i].biggest_mode);
139 : 2843500 : poly_int64 total_size = GET_MODE_SIZE (wider_mode);
140 : 1421750 : poly_int64 adjust = 0;
141 : :
142 : 1421750 : lra_assert (regno_reg_rtx[i] != NULL_RTX && REG_P (regno_reg_rtx[i])
143 : : && lra_reg_info[i].nrefs != 0 && reg_renumber[i] < 0);
144 : :
145 : 1421750 : unsigned int slot_num = pseudo_slots[i].slot_num;
146 : 1421750 : x = slots[slot_num].mem;
147 : 1421750 : if (!x)
148 : : {
149 : 1536026 : x = assign_stack_local (BLKmode, slots[slot_num].size,
150 : 768013 : slots[slot_num].align);
151 : 768013 : slots[slot_num].mem = x;
152 : : }
153 : :
154 : : /* On a big endian machine, the "address" of the slot is the address
155 : : of the low part that fits its inherent mode. */
156 : 1421750 : adjust += subreg_size_lowpart_offset (inherent_size, total_size);
157 : 1421750 : x = adjust_address_nv (x, GET_MODE (regno_reg_rtx[i]), adjust);
158 : :
159 : : /* Set all of the memory attributes as appropriate for a spill. */
160 : 1421750 : set_mem_attrs_for_spill (x);
161 : 1421750 : pseudo_slots[i].mem = x;
162 : 1421750 : }
163 : :
164 : : /* Sort pseudos according their usage frequencies. */
165 : : static int
166 : 29737687 : regno_freq_compare (const void *v1p, const void *v2p)
167 : : {
168 : 29737687 : const int regno1 = *(const int *) v1p;
169 : 29737687 : const int regno2 = *(const int *) v2p;
170 : 29737687 : int diff;
171 : :
172 : 29737687 : if ((diff = lra_reg_info[regno2].freq - lra_reg_info[regno1].freq) != 0)
173 : : return diff;
174 : 11660704 : return regno1 - regno2;
175 : : }
176 : :
177 : : /* Sort pseudos according to their slots, putting the slots in the order
178 : : that they should be allocated.
179 : :
180 : : First prefer to group slots with variable sizes together and slots
181 : : with constant sizes together, since that usually makes them easier
182 : : to address from a common anchor point. E.g. loads of polynomial-sized
183 : : registers tend to take polynomial offsets while loads of constant-sized
184 : : registers tend to take constant (non-polynomial) offsets.
185 : :
186 : : Next, slots with lower numbers have the highest priority and should
187 : : get the smallest displacement from the stack or frame pointer
188 : : (whichever is being used).
189 : :
190 : : The first allocated slot is always closest to the frame pointer,
191 : : so prefer lower slot numbers when frame_pointer_needed. If the stack
192 : : and frame grow in the same direction, then the first allocated slot is
193 : : always closest to the initial stack pointer and furthest away from the
194 : : final stack pointer, so allocate higher numbers first when using the
195 : : stack pointer in that case. The reverse is true if the stack and
196 : : frame grow in opposite directions. */
197 : : static int
198 : 30153607 : pseudo_reg_slot_compare (const void *v1p, const void *v2p)
199 : : {
200 : 30153607 : const int regno1 = *(const int *) v1p;
201 : 30153607 : const int regno2 = *(const int *) v2p;
202 : 30153607 : int diff, slot_num1, slot_num2;
203 : :
204 : 30153607 : slot_num1 = pseudo_slots[regno1].slot_num;
205 : 30153607 : slot_num2 = pseudo_slots[regno2].slot_num;
206 : 30153607 : diff = (int (slots[slot_num1].size.is_constant ())
207 : 30153607 : - int (slots[slot_num2].size.is_constant ()));
208 : 30153607 : if (diff != 0)
209 : : return diff;
210 : 30153607 : if ((diff = slot_num1 - slot_num2) != 0)
211 : 22334824 : return (frame_pointer_needed
212 : 22334824 : || (!FRAME_GROWS_DOWNWARD) == STACK_GROWS_DOWNWARD ? diff : -diff);
213 : 15637566 : poly_int64 total_size1 = GET_MODE_SIZE (lra_reg_info[regno1].biggest_mode);
214 : 15637566 : poly_int64 total_size2 = GET_MODE_SIZE (lra_reg_info[regno2].biggest_mode);
215 : 7818783 : if ((diff = compare_sizes_for_sort (total_size2, total_size1)) != 0)
216 : 1577413 : return diff;
217 : 6241370 : return regno1 - regno2;
218 : : }
219 : :
220 : : /* Assign spill hard registers to N pseudos in PSEUDO_REGNOS which is
221 : : sorted in order of highest frequency first. Put the pseudos which
222 : : did not get a spill hard register at the beginning of array
223 : : PSEUDO_REGNOS. Return the number of such pseudos. */
224 : : static int
225 : 215997 : assign_spill_hard_regs (int *pseudo_regnos, int n)
226 : : {
227 : 215997 : int i, k, p, regno, res, spill_class_size, hard_regno, nr;
228 : 215997 : enum reg_class rclass, spill_class;
229 : 215997 : machine_mode mode;
230 : 215997 : lra_live_range_t r;
231 : 215997 : rtx_insn *insn;
232 : 215997 : rtx set;
233 : 215997 : basic_block bb;
234 : 215997 : HARD_REG_SET conflict_hard_regs;
235 : 215997 : bitmap setjump_crosses = regstat_get_setjmp_crosses ();
236 : : /* Hard registers which cannot be used for any purpose at given
237 : : program point because they are unallocatable or already allocated
238 : : for other pseudos. */
239 : 215997 : HARD_REG_SET *reserved_hard_regs;
240 : :
241 : 215997 : if (! lra_reg_spill_p)
242 : : return n;
243 : : /* Set up reserved hard regs for every program point. */
244 : 0 : reserved_hard_regs = XNEWVEC (HARD_REG_SET, lra_live_max_point);
245 : 0 : for (p = 0; p < lra_live_max_point; p++)
246 : 0 : reserved_hard_regs[p] = lra_no_alloc_regs;
247 : 0 : for (i = FIRST_PSEUDO_REGISTER; i < regs_num; i++)
248 : 0 : if (lra_reg_info[i].nrefs != 0
249 : 0 : && (hard_regno = lra_get_regno_hard_regno (i)) >= 0)
250 : 0 : for (r = lra_reg_info[i].live_ranges; r != NULL; r = r->next)
251 : 0 : for (p = r->start; p <= r->finish; p++)
252 : 0 : add_to_hard_reg_set (&reserved_hard_regs[p],
253 : : lra_reg_info[i].biggest_mode, hard_regno);
254 : 0 : auto_bitmap ok_insn_bitmap (®_obstack);
255 : 0 : FOR_EACH_BB_FN (bb, cfun)
256 : 0 : FOR_BB_INSNS (bb, insn)
257 : 0 : if (DEBUG_INSN_P (insn)
258 : 0 : || ((set = single_set (insn)) != NULL_RTX
259 : 0 : && REG_P (SET_SRC (set)) && REG_P (SET_DEST (set))))
260 : 0 : bitmap_set_bit (ok_insn_bitmap, INSN_UID (insn));
261 : 0 : for (res = i = 0; i < n; i++)
262 : : {
263 : 0 : regno = pseudo_regnos[i];
264 : 0 : rclass = lra_get_allocno_class (regno);
265 : 0 : if (bitmap_bit_p (setjump_crosses, regno)
266 : 0 : || (spill_class
267 : 0 : = ((enum reg_class)
268 : 0 : targetm.spill_class ((reg_class_t) rclass,
269 : 0 : PSEUDO_REGNO_MODE (regno)))) == NO_REGS
270 : 0 : || bitmap_intersect_compl_p (&lra_reg_info[regno].insn_bitmap,
271 : : ok_insn_bitmap))
272 : : {
273 : 0 : pseudo_regnos[res++] = regno;
274 : 0 : continue;
275 : : }
276 : 0 : lra_assert (spill_class != NO_REGS);
277 : 0 : conflict_hard_regs = lra_reg_info[regno].conflict_hard_regs;
278 : 0 : for (r = lra_reg_info[regno].live_ranges; r != NULL; r = r->next)
279 : 0 : for (p = r->start; p <= r->finish; p++)
280 : 0 : conflict_hard_regs |= reserved_hard_regs[p];
281 : 0 : spill_class_size = ira_class_hard_regs_num[spill_class];
282 : 0 : mode = lra_reg_info[regno].biggest_mode;
283 : 0 : for (k = 0; k < spill_class_size; k++)
284 : : {
285 : 0 : hard_regno = ira_class_hard_regs[spill_class][k];
286 : 0 : if (TEST_HARD_REG_BIT (eliminable_regset, hard_regno)
287 : 0 : || !targetm.hard_regno_mode_ok (hard_regno, mode))
288 : 0 : continue;
289 : 0 : if (! overlaps_hard_reg_set_p (conflict_hard_regs, mode, hard_regno))
290 : : break;
291 : : }
292 : 0 : if (k >= spill_class_size)
293 : : {
294 : : /* There is no available regs -- assign memory later. */
295 : 0 : pseudo_regnos[res++] = regno;
296 : 0 : continue;
297 : : }
298 : 0 : if (lra_dump_file != NULL)
299 : 0 : fprintf (lra_dump_file, " Spill r%d into hr%d\n", regno, hard_regno);
300 : 0 : add_to_hard_reg_set (&hard_regs_spilled_into,
301 : 0 : lra_reg_info[regno].biggest_mode, hard_regno);
302 : : /* Update reserved_hard_regs. */
303 : 0 : for (r = lra_reg_info[regno].live_ranges; r != NULL; r = r->next)
304 : 0 : for (p = r->start; p <= r->finish; p++)
305 : 0 : add_to_hard_reg_set (&reserved_hard_regs[p],
306 : : lra_reg_info[regno].biggest_mode, hard_regno);
307 : 0 : spill_hard_reg[regno]
308 : 0 : = gen_raw_REG (PSEUDO_REGNO_MODE (regno), hard_regno);
309 : 0 : for (nr = 0;
310 : 0 : nr < hard_regno_nregs (hard_regno,
311 : 0 : lra_reg_info[regno].biggest_mode);
312 : : nr++)
313 : : /* Just loop. */
314 : 0 : df_set_regs_ever_live (hard_regno + nr, true);
315 : : }
316 : 0 : free (reserved_hard_regs);
317 : 0 : return res;
318 : 0 : }
319 : :
320 : : /* Add pseudo REGNO to slot SLOT_NUM. */
321 : : static void
322 : 1421750 : add_pseudo_to_slot (int regno, int slot_num)
323 : : {
324 : 1421750 : struct pseudo_slot *first;
325 : :
326 : : /* Each pseudo has an inherent size which comes from its own mode,
327 : : and a total size which provides room for paradoxical subregs.
328 : : We need to make sure the size and alignment of the slot are
329 : : sufficient for both. */
330 : 2843500 : machine_mode mode = wider_subreg_mode (PSEUDO_REGNO_MODE (regno),
331 : 1421750 : lra_reg_info[regno].biggest_mode);
332 : 1421750 : unsigned int align = spill_slot_alignment (mode);
333 : 1421750 : slots[slot_num].align = MAX (slots[slot_num].align, align);
334 : 1421750 : slots[slot_num].size = upper_bound (slots[slot_num].size,
335 : 1421750 : GET_MODE_SIZE (mode));
336 : :
337 : 1421750 : if (slots[slot_num].regno < 0)
338 : : {
339 : : /* It is the first pseudo in the slot. */
340 : 768013 : slots[slot_num].regno = regno;
341 : 768013 : pseudo_slots[regno].first = &pseudo_slots[regno];
342 : 768013 : pseudo_slots[regno].next = NULL;
343 : : }
344 : : else
345 : : {
346 : 653737 : first = pseudo_slots[regno].first = &pseudo_slots[slots[slot_num].regno];
347 : 653737 : pseudo_slots[regno].next = first->next;
348 : 653737 : first->next = &pseudo_slots[regno];
349 : : }
350 : 1421750 : pseudo_slots[regno].mem = NULL_RTX;
351 : 1421750 : pseudo_slots[regno].slot_num = slot_num;
352 : 1421750 : slots[slot_num].live_ranges
353 : 1421750 : = lra_merge_live_ranges (slots[slot_num].live_ranges,
354 : : lra_copy_live_range_list
355 : 1421750 : (lra_reg_info[regno].live_ranges));
356 : 1421750 : }
357 : :
358 : : /* Assign stack slot numbers to pseudos in array PSEUDO_REGNOS of
359 : : length N. Sort pseudos in PSEUDO_REGNOS for subsequent assigning
360 : : memory stack slots. */
361 : : static void
362 : 215997 : assign_stack_slot_num_and_sort_pseudos (int *pseudo_regnos, int n)
363 : : {
364 : 215997 : int i, j, regno;
365 : :
366 : : /* Assign stack slot numbers to spilled pseudos, use smaller numbers
367 : : for most frequently used pseudos. */
368 : 1637747 : for (i = 0; i < n; i++)
369 : : {
370 : 1421750 : regno = pseudo_regnos[i];
371 : 1421750 : if (! flag_ira_share_spill_slots)
372 : 27572 : j = slots_num;
373 : : else
374 : : {
375 : 1394178 : machine_mode mode
376 : 2788356 : = wider_subreg_mode (PSEUDO_REGNO_MODE (regno),
377 : 1394178 : lra_reg_info[regno].biggest_mode);
378 : 26373587 : for (j = 0; j < slots_num; j++)
379 : 25633146 : if (slots[j].hard_regno < 0
380 : : /* Although it's possible to share slots between modes
381 : : with constant and non-constant widths, we usually
382 : : get better spill code by keeping the constant and
383 : : non-constant areas separate. */
384 : 25633146 : && (GET_MODE_SIZE (mode).is_constant ()
385 : : == slots[j].size.is_constant ())
386 : 51266292 : && ! (lra_intersected_live_ranges_p
387 : 25633146 : (slots[j].live_ranges,
388 : 25633146 : lra_reg_info[regno].live_ranges)))
389 : : break;
390 : : }
391 : 1421750 : if (j >= slots_num)
392 : : {
393 : : /* New slot. */
394 : 768013 : slots[j].live_ranges = NULL;
395 : 768013 : slots[j].size = 0;
396 : 768013 : slots[j].align = BITS_PER_UNIT;
397 : 768013 : slots[j].regno = slots[j].hard_regno = -1;
398 : 768013 : slots[j].mem = NULL_RTX;
399 : 768013 : slots_num++;
400 : : }
401 : 1421750 : add_pseudo_to_slot (regno, j);
402 : : }
403 : : /* Sort regnos according to their slot numbers. */
404 : 215997 : qsort (pseudo_regnos, n, sizeof (int), pseudo_reg_slot_compare);
405 : 215997 : }
406 : :
407 : : /* Recursively process LOC in INSN and change spilled pseudos to the
408 : : corresponding memory or spilled hard reg. Ignore spilled pseudos
409 : : created from the scratches. Return true if the pseudo nrefs equal
410 : : to 0 (don't change the pseudo in this case). Otherwise return false. */
411 : : static bool
412 : 33671359 : remove_pseudos (rtx *loc, rtx_insn *insn)
413 : : {
414 : 33671359 : int i;
415 : 33671359 : rtx hard_reg;
416 : 33671359 : const char *fmt;
417 : 33671359 : enum rtx_code code;
418 : 33671359 : bool res = false;
419 : :
420 : 33671359 : if (*loc == NULL_RTX)
421 : : return res;
422 : 30933636 : code = GET_CODE (*loc);
423 : 30933636 : if (code == SUBREG && REG_P (SUBREG_REG (*loc)))
424 : : {
425 : : /* Try to remove memory subregs to simplify LRA job
426 : : and avoid LRA cycling in case of subreg memory reload. */
427 : 267957 : res = remove_pseudos (&SUBREG_REG (*loc), insn);
428 : 267957 : if (GET_CODE (SUBREG_REG (*loc)) == MEM)
429 : : {
430 : 203973 : alter_subreg (loc, false);
431 : 203973 : if (GET_CODE (*loc) == MEM)
432 : : {
433 : 203973 : lra_update_insn_recog_data (insn);
434 : 203973 : if (lra_dump_file != NULL)
435 : 0 : fprintf (lra_dump_file,
436 : : "Memory subreg was simplified in insn #%u\n",
437 : 0 : INSN_UID (insn));
438 : : }
439 : : }
440 : 267957 : return res;
441 : : }
442 : 14257801 : else if (code == REG && (i = REGNO (*loc)) >= FIRST_PSEUDO_REGISTER
443 : 8617913 : && lra_get_regno_hard_regno (i) < 0
444 : : /* We do not want to assign memory for former scratches because
445 : : it might result in an address reload for some targets. In
446 : : any case we transform such pseudos not getting hard registers
447 : : into scratches back. */
448 : 35579097 : && ! ira_former_scratch_p (i))
449 : : {
450 : 4913418 : if (lra_reg_info[i].nrefs == 0
451 : 23176 : && pseudo_slots[i].mem == NULL && spill_hard_reg[i] == NULL)
452 : : return true;
453 : 4913418 : if ((hard_reg = spill_hard_reg[i]) != NULL_RTX)
454 : 0 : *loc = copy_rtx (hard_reg);
455 : 4913418 : else if (pseudo_slots[i].mem != NULL_RTX)
456 : : /* There might be no memory slot or hard reg for a pseudo when we spill
457 : : the frame pointer after elimination of frame pointer to stack
458 : : pointer became impossible. */
459 : : {
460 : 9826836 : rtx x = lra_eliminate_regs_1 (insn, pseudo_slots[i].mem,
461 : 4913418 : GET_MODE (pseudo_slots[i].mem),
462 : 4913418 : false, false, 0, true);
463 : 4913418 : *loc = x != pseudo_slots[i].mem ? x : copy_rtx (x);
464 : : }
465 : 4913418 : return res;
466 : : }
467 : :
468 : 25752261 : fmt = GET_RTX_FORMAT (code);
469 : 62109370 : for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
470 : : {
471 : 36357109 : if (fmt[i] == 'e')
472 : 25605246 : res = remove_pseudos (&XEXP (*loc, i), insn) || res;
473 : 10751863 : else if (fmt[i] == 'E')
474 : : {
475 : 101961 : int j;
476 : :
477 : 317426 : for (j = XVECLEN (*loc, i) - 1; j >= 0; j--)
478 : 215465 : res = remove_pseudos (&XVECEXP (*loc, i, j), insn) || res;
479 : : }
480 : : }
481 : : return res;
482 : : }
483 : :
484 : : /* Convert spilled pseudos into their stack slots or spill hard regs,
485 : : put insns to process on the constraint stack (that is all insns in
486 : : which pseudos were changed to memory or spill hard regs). */
487 : : static void
488 : 215997 : spill_pseudos (void)
489 : : {
490 : 215997 : basic_block bb;
491 : 215997 : rtx_insn *insn, *curr;
492 : 215997 : int i;
493 : :
494 : 215997 : auto_bitmap spilled_pseudos (®_obstack);
495 : 215997 : auto_bitmap changed_insns (®_obstack);
496 : 34783305 : for (i = FIRST_PSEUDO_REGISTER; i < regs_num; i++)
497 : : {
498 : 17755457 : if (lra_reg_info[i].nrefs != 0 && lra_get_regno_hard_regno (i) < 0
499 : 35992421 : && ! ira_former_scratch_p (i))
500 : : {
501 : 1421750 : bitmap_set_bit (spilled_pseudos, i);
502 : 1421750 : bitmap_ior_into (changed_insns, &lra_reg_info[i].insn_bitmap);
503 : : }
504 : : }
505 : 6778479 : FOR_EACH_BB_FN (bb, cfun)
506 : : {
507 : 192951926 : FOR_BB_INSNS_SAFE (bb, insn, curr)
508 : : {
509 : 89913481 : bool removed_pseudo_p = false;
510 : :
511 : 89913481 : if (bitmap_bit_p (changed_insns, INSN_UID (insn)))
512 : : {
513 : 4844968 : rtx *link_loc, link;
514 : :
515 : 4844968 : removed_pseudo_p = remove_pseudos (&PATTERN (insn), insn);
516 : 4844968 : if (CALL_P (insn)
517 : 4844968 : && remove_pseudos (&CALL_INSN_FUNCTION_USAGE (insn), insn))
518 : : removed_pseudo_p = true;
519 : 4844968 : for (link_loc = ®_NOTES (insn);
520 : 8162974 : (link = *link_loc) != NULL_RTX;
521 : 3318006 : link_loc = &XEXP (link, 1))
522 : : {
523 : 3318006 : switch (REG_NOTE_KIND (link))
524 : : {
525 : 0 : case REG_FRAME_RELATED_EXPR:
526 : 0 : case REG_CFA_DEF_CFA:
527 : 0 : case REG_CFA_ADJUST_CFA:
528 : 0 : case REG_CFA_OFFSET:
529 : 0 : case REG_CFA_REGISTER:
530 : 0 : case REG_CFA_EXPRESSION:
531 : 0 : case REG_CFA_RESTORE:
532 : 0 : case REG_CFA_SET_VDRAP:
533 : 0 : if (remove_pseudos (&XEXP (link, 0), insn))
534 : 3318006 : removed_pseudo_p = true;
535 : : break;
536 : : default:
537 : : break;
538 : : }
539 : : }
540 : 4844968 : if (GET_CODE (PATTERN (insn)) == CLOBBER)
541 : : /* This is a CLOBBER insn with pseudo spilled to memory.
542 : : Mark it for removing it later together with LRA temporary
543 : : CLOBBER insns. */
544 : 6856 : LRA_TEMP_CLOBBER_P (PATTERN (insn)) = 1;
545 : 4844968 : if (lra_dump_file != NULL)
546 : 6 : fprintf (lra_dump_file,
547 : : "Changing spilled pseudos to memory in insn #%u\n",
548 : 6 : INSN_UID (insn));
549 : 4844968 : lra_push_insn (insn);
550 : 4844968 : if (lra_reg_spill_p || targetm.different_addr_displacement_p ())
551 : 0 : lra_set_used_insn_alternative (insn, LRA_UNKNOWN_ALT);
552 : : }
553 : 85068513 : else if (CALL_P (insn)
554 : : /* Presence of any pseudo in CALL_INSN_FUNCTION_USAGE
555 : : does not affect value of insn_bitmap of the
556 : : corresponding lra_reg_info. That is because we
557 : : don't need to reload pseudos in
558 : : CALL_INSN_FUNCTION_USAGEs. So if we process only
559 : : insns in the insn_bitmap of given pseudo here, we
560 : : can miss the pseudo in some
561 : : CALL_INSN_FUNCTION_USAGEs. */
562 : 85068513 : && remove_pseudos (&CALL_INSN_FUNCTION_USAGE (insn), insn))
563 : : removed_pseudo_p = true;
564 : 4844968 : if (removed_pseudo_p)
565 : : {
566 : 0 : lra_assert (DEBUG_INSN_P (insn));
567 : 0 : lra_invalidate_insn_data (insn);
568 : 0 : INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC ();
569 : 0 : if (lra_dump_file != NULL)
570 : 0 : fprintf (lra_dump_file,
571 : : "Debug insn #%u is reset because it referenced "
572 : 0 : "removed pseudo\n", INSN_UID (insn));
573 : : }
574 : 89913481 : bitmap_and_compl_into (df_get_live_in (bb), spilled_pseudos);
575 : 89913481 : bitmap_and_compl_into (df_get_live_out (bb), spilled_pseudos);
576 : : }
577 : : }
578 : 215997 : }
579 : :
580 : : /* Return true if we need scratch reg assignments. */
581 : : bool
582 : 331 : lra_need_for_scratch_reg_p (void)
583 : : {
584 : 331 : int i; max_regno = max_reg_num ();
585 : :
586 : 17936 : for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
587 : 6534 : if (lra_reg_info[i].nrefs != 0 && lra_get_regno_hard_regno (i) < 0
588 : 17605 : && ira_former_scratch_p (i))
589 : : return true;
590 : : return false;
591 : : }
592 : :
593 : : /* Return true if we need to change some pseudos into memory. */
594 : : bool
595 : 1633667 : lra_need_for_spills_p (void)
596 : : {
597 : 1633667 : int i;
598 : :
599 : 1633667 : max_regno = max_reg_num ();
600 : 86313493 : for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
601 : 38632691 : if (lra_reg_info[i].nrefs != 0 && lra_get_regno_hard_regno (i) < 0
602 : 85121477 : && ! ira_former_scratch_p (i))
603 : : return true;
604 : : return false;
605 : : }
606 : :
607 : : /* Change spilled pseudos into memory or spill hard regs. Put changed
608 : : insns on the constraint stack (these insns will be considered on
609 : : the next constraint pass). The changed insns are all insns in
610 : : which pseudos were changed. */
611 : : void
612 : 215997 : lra_spill (void)
613 : : {
614 : 215997 : int i, n, n2, curr_regno;
615 : 215997 : int *pseudo_regnos;
616 : :
617 : 215997 : regs_num = max_reg_num ();
618 : 215997 : spill_hard_reg = XNEWVEC (rtx, regs_num);
619 : 215997 : pseudo_regnos = XNEWVEC (int, regs_num);
620 : 34999302 : for (n = 0, i = FIRST_PSEUDO_REGISTER; i < regs_num; i++)
621 : 17755457 : if (lra_reg_info[i].nrefs != 0 && lra_get_regno_hard_regno (i) < 0
622 : : /* We do not want to assign memory for former scratches. */
623 : 35992421 : && ! ira_former_scratch_p (i))
624 : 1421750 : pseudo_regnos[n++] = i;
625 : 215997 : lra_assert (n > 0);
626 : 215997 : pseudo_slots = XNEWVEC (struct pseudo_slot, regs_num);
627 : 34783305 : for (i = FIRST_PSEUDO_REGISTER; i < regs_num; i++)
628 : : {
629 : 34567308 : spill_hard_reg[i] = NULL_RTX;
630 : 34567308 : pseudo_slots[i].mem = NULL_RTX;
631 : : }
632 : 215997 : slots = XNEWVEC (class slot, regs_num);
633 : : /* Sort regnos according their usage frequencies. */
634 : 215997 : qsort (pseudo_regnos, n, sizeof (int), regno_freq_compare);
635 : 215997 : n = assign_spill_hard_regs (pseudo_regnos, n);
636 : 215997 : slots_num = 0;
637 : 215997 : assign_stack_slot_num_and_sort_pseudos (pseudo_regnos, n);
638 : 1853744 : for (i = 0; i < n; i++)
639 : 1421750 : if (pseudo_slots[pseudo_regnos[i]].mem == NULL_RTX)
640 : 1421750 : assign_mem_slot (pseudo_regnos[i]);
641 : 215997 : if ((n2 = lra_update_fp2sp_elimination (pseudo_regnos)) > 0)
642 : : {
643 : : /* Assign stack slots to spilled pseudos assigned to fp. */
644 : 0 : assign_stack_slot_num_and_sort_pseudos (pseudo_regnos, n2);
645 : 0 : for (i = 0; i < n2; i++)
646 : 0 : if (pseudo_slots[pseudo_regnos[i]].mem == NULL_RTX)
647 : 0 : assign_mem_slot (pseudo_regnos[i]);
648 : : }
649 : 215997 : if (n + n2 > 0 && crtl->stack_alignment_needed)
650 : : /* If we have a stack frame, we must align it now. The stack size
651 : : may be a part of the offset computation for register
652 : : elimination. */
653 : 215997 : assign_stack_local (BLKmode, 0, crtl->stack_alignment_needed);
654 : 215997 : if (lra_dump_file != NULL)
655 : : {
656 : 3 : for (i = 0; i < slots_num; i++)
657 : : {
658 : 2 : fprintf (lra_dump_file, " Slot %d regnos (width = ", i);
659 : 2 : print_dec (GET_MODE_SIZE (GET_MODE (slots[i].mem)),
660 : : lra_dump_file, SIGNED);
661 : 2 : fprintf (lra_dump_file, "):");
662 : 2 : for (curr_regno = slots[i].regno;;
663 : 0 : curr_regno = pseudo_slots[curr_regno].next - pseudo_slots)
664 : : {
665 : 2 : fprintf (lra_dump_file, " %d", curr_regno);
666 : 2 : if (pseudo_slots[curr_regno].next == NULL)
667 : : break;
668 : : }
669 : 2 : fprintf (lra_dump_file, "\n");
670 : : }
671 : : }
672 : 215997 : spill_pseudos ();
673 : 215997 : free (slots);
674 : 215997 : free (pseudo_slots);
675 : 215997 : free (pseudo_regnos);
676 : 215997 : free (spill_hard_reg);
677 : 215997 : }
678 : :
679 : : /* Apply alter_subreg for subregs of regs in *LOC. Use FINAL_P for
680 : : alter_subreg calls. Return true if any subreg of reg is
681 : : processed. */
682 : : static bool
683 : 324233973 : alter_subregs (rtx *loc, bool final_p)
684 : : {
685 : 324233973 : int i;
686 : 324233973 : rtx x = *loc;
687 : 324233973 : bool res;
688 : 324233973 : const char *fmt;
689 : 324233973 : enum rtx_code code;
690 : :
691 : 324233973 : if (x == NULL_RTX)
692 : : return false;
693 : 324233973 : code = GET_CODE (x);
694 : 324233973 : if (code == SUBREG && REG_P (SUBREG_REG (x)))
695 : : {
696 : 2939293 : lra_assert (REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER);
697 : 2939293 : alter_subreg (loc, final_p);
698 : 2939293 : return true;
699 : : }
700 : 321294680 : fmt = GET_RTX_FORMAT (code);
701 : 321294680 : res = false;
702 : 770818575 : for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
703 : : {
704 : 449523895 : if (fmt[i] == 'e')
705 : : {
706 : 110214306 : if (alter_subregs (&XEXP (x, i), final_p))
707 : 449523895 : res = true;
708 : : }
709 : 339309589 : else if (fmt[i] == 'E')
710 : : {
711 : 469669 : int j;
712 : :
713 : 2135729 : for (j = XVECLEN (x, i) - 1; j >= 0; j--)
714 : 1666060 : if (alter_subregs (&XVECEXP (x, i, j), final_p))
715 : 416 : res = true;
716 : : }
717 : : }
718 : : return res;
719 : : }
720 : :
721 : : /* Final change of pseudos got hard registers into the corresponding
722 : : hard registers and removing temporary clobbers. */
723 : : void
724 : 1415660 : lra_final_code_change (void)
725 : : {
726 : 1415660 : int i, hard_regno;
727 : 1415660 : basic_block bb;
728 : 1415660 : rtx_insn *insn, *curr;
729 : 1415660 : rtx set;
730 : 1415660 : int max_regno = max_reg_num ();
731 : :
732 : 74920842 : for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
733 : 72089522 : if (lra_reg_info[i].nrefs != 0
734 : 105653881 : && (hard_regno = lra_get_regno_hard_regno (i)) >= 0)
735 : 33559014 : SET_REGNO (regno_reg_rtx[i], hard_regno);
736 : 14976834 : FOR_EACH_BB_FN (bb, cfun)
737 : 338384594 : FOR_BB_INSNS_SAFE (bb, insn, curr)
738 : 155631123 : if (INSN_P (insn))
739 : : {
740 : 128890490 : rtx pat = PATTERN (insn);
741 : :
742 : 128890490 : if (GET_CODE (pat) == USE && XEXP (pat, 0) == const1_rtx)
743 : : {
744 : : /* Remove markers to eliminate critical edges for jump insn
745 : : output reloads (see code in ira.cc::ira). */
746 : 11 : lra_invalidate_insn_data (insn);
747 : 11 : delete_insn (insn);
748 : 11 : continue;
749 : : }
750 : 128890479 : if (GET_CODE (pat) == CLOBBER && LRA_TEMP_CLOBBER_P (pat))
751 : : {
752 : : /* Remove clobbers temporarily created in LRA. We don't
753 : : need them anymore and don't want to waste compiler
754 : : time processing them in a few subsequent passes. */
755 : 133852 : lra_invalidate_insn_data (insn);
756 : 133852 : delete_insn (insn);
757 : 133852 : continue;
758 : : }
759 : :
760 : : /* IRA can generate move insns involving pseudos. It is
761 : : better remove them earlier to speed up compiler a bit.
762 : : It is also better to do it here as they might not pass
763 : : final RTL check in LRA, (e.g. insn moving a control
764 : : register into itself). So remove an useless move insn
765 : : unless next insn is USE marking the return reg (we should
766 : : save this as some subsequent optimizations assume that
767 : : such original insns are saved). */
768 : 74849754 : if (NONJUMP_INSN_P (insn) && GET_CODE (pat) == SET
769 : 63400306 : && REG_P (SET_SRC (pat)) && REG_P (SET_DEST (pat))
770 : 16428345 : && REGNO (SET_SRC (pat)) == REGNO (SET_DEST (pat))
771 : 138933000 : && REGNO (SET_SRC (pat)) >= FIRST_PSEUDO_REGISTER)
772 : : {
773 : 0 : lra_invalidate_insn_data (insn);
774 : 0 : delete_insn (insn);
775 : 0 : continue;
776 : : }
777 : :
778 : 128756627 : lra_insn_recog_data_t id = lra_get_insn_recog_data (insn);
779 : 128756627 : struct lra_insn_reg *reg;
780 : :
781 : 273664076 : for (reg = id->regs; reg != NULL; reg = reg->next)
782 : 144907704 : if (reg->regno >= FIRST_PSEUDO_REGISTER
783 : 94906382 : && lra_reg_info [reg->regno].nrefs == 0)
784 : : break;
785 : :
786 : 128756627 : if (reg != NULL)
787 : : {
788 : : /* Pseudos still can be in debug insns in some very rare
789 : : and complicated cases, e.g. the pseudo was removed by
790 : : inheritance and the debug insn is not EBBs where the
791 : : inheritance happened. It is difficult and time
792 : : consuming to find what hard register corresponds the
793 : : pseudo -- so just remove the debug insn. Another
794 : : solution could be assigning hard reg/memory but it
795 : : would be a misleading info. It is better not to have
796 : : info than have it wrong. */
797 : 255 : lra_assert (DEBUG_INSN_P (insn));
798 : 255 : lra_invalidate_insn_data (insn);
799 : 255 : delete_insn (insn);
800 : 255 : continue;
801 : : }
802 : :
803 : 128756372 : struct lra_static_insn_data *static_id = id->insn_static_data;
804 : 128756372 : bool insn_change_p = false;
805 : :
806 : 347346048 : for (i = id->insn_static_data->n_operands - 1; i >= 0; i--)
807 : 188463271 : if ((DEBUG_INSN_P (insn) || ! static_id->operand[i].is_operator)
808 : 400040878 : && alter_subregs (id->operand_loc[i], ! DEBUG_INSN_P (insn)))
809 : : {
810 : 2937581 : lra_update_dup (id, i);
811 : 2937581 : insn_change_p = true;
812 : : }
813 : 128756372 : if ((GET_CODE (pat) == USE || GET_CODE (pat) == CLOBBER)
814 : 128756372 : && alter_subregs (&XEXP (pat, 0), false))
815 : : insn_change_p = true;
816 : 128756372 : if (insn_change_p)
817 : 2602888 : lra_update_operator_dups (id);
818 : :
819 : 128756372 : if ((set = single_set (insn)) != NULL
820 : 83742417 : && REG_P (SET_SRC (set)) && REG_P (SET_DEST (set))
821 : 146183727 : && REGNO (SET_SRC (set)) == REGNO (SET_DEST (set)))
822 : : {
823 : : /* Remove an useless move insn. IRA can generate move
824 : : insns involving pseudos. It is better remove them
825 : : earlier to speed up compiler a bit. It is also
826 : : better to do it here as they might not pass final RTL
827 : : check in LRA, (e.g. insn moving a control register
828 : : into itself). */
829 : 10505318 : lra_invalidate_insn_data (insn);
830 : 10505318 : delete_insn (insn);
831 : : }
832 : : }
833 : 1415660 : }
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