2018-01-10 François Dumont <fdumont@gcc.gnu.org>
[official-gcc.git] / gcc / rtlanal.c
blobb7283910f74252a0f0b53d2bce2300c3a31c8796
1 /* Analyze RTL for GNU compiler.
2 Copyright (C) 1987-2018 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
21 #include "config.h"
22 #include "system.h"
23 #include "coretypes.h"
24 #include "backend.h"
25 #include "target.h"
26 #include "rtl.h"
27 #include "tree.h"
28 #include "predict.h"
29 #include "df.h"
30 #include "memmodel.h"
31 #include "tm_p.h"
32 #include "insn-config.h"
33 #include "regs.h"
34 #include "emit-rtl.h" /* FIXME: Can go away once crtl is moved to rtl.h. */
35 #include "recog.h"
36 #include "addresses.h"
37 #include "rtl-iter.h"
39 /* Forward declarations */
40 static void set_of_1 (rtx, const_rtx, void *);
41 static bool covers_regno_p (const_rtx, unsigned int);
42 static bool covers_regno_no_parallel_p (const_rtx, unsigned int);
43 static int computed_jump_p_1 (const_rtx);
44 static void parms_set (rtx, const_rtx, void *);
46 static unsigned HOST_WIDE_INT cached_nonzero_bits (const_rtx, scalar_int_mode,
47 const_rtx, machine_mode,
48 unsigned HOST_WIDE_INT);
49 static unsigned HOST_WIDE_INT nonzero_bits1 (const_rtx, scalar_int_mode,
50 const_rtx, machine_mode,
51 unsigned HOST_WIDE_INT);
52 static unsigned int cached_num_sign_bit_copies (const_rtx, scalar_int_mode,
53 const_rtx, machine_mode,
54 unsigned int);
55 static unsigned int num_sign_bit_copies1 (const_rtx, scalar_int_mode,
56 const_rtx, machine_mode,
57 unsigned int);
59 rtx_subrtx_bound_info rtx_all_subrtx_bounds[NUM_RTX_CODE];
60 rtx_subrtx_bound_info rtx_nonconst_subrtx_bounds[NUM_RTX_CODE];
62 /* Truncation narrows the mode from SOURCE mode to DESTINATION mode.
63 If TARGET_MODE_REP_EXTENDED (DESTINATION, DESTINATION_REP) is
64 SIGN_EXTEND then while narrowing we also have to enforce the
65 representation and sign-extend the value to mode DESTINATION_REP.
67 If the value is already sign-extended to DESTINATION_REP mode we
68 can just switch to DESTINATION mode on it. For each pair of
69 integral modes SOURCE and DESTINATION, when truncating from SOURCE
70 to DESTINATION, NUM_SIGN_BIT_COPIES_IN_REP[SOURCE][DESTINATION]
71 contains the number of high-order bits in SOURCE that have to be
72 copies of the sign-bit so that we can do this mode-switch to
73 DESTINATION. */
75 static unsigned int
76 num_sign_bit_copies_in_rep[MAX_MODE_INT + 1][MAX_MODE_INT + 1];
78 /* Store X into index I of ARRAY. ARRAY is known to have at least I
79 elements. Return the new base of ARRAY. */
81 template <typename T>
82 typename T::value_type *
83 generic_subrtx_iterator <T>::add_single_to_queue (array_type &array,
84 value_type *base,
85 size_t i, value_type x)
87 if (base == array.stack)
89 if (i < LOCAL_ELEMS)
91 base[i] = x;
92 return base;
94 gcc_checking_assert (i == LOCAL_ELEMS);
95 /* A previous iteration might also have moved from the stack to the
96 heap, in which case the heap array will already be big enough. */
97 if (vec_safe_length (array.heap) <= i)
98 vec_safe_grow (array.heap, i + 1);
99 base = array.heap->address ();
100 memcpy (base, array.stack, sizeof (array.stack));
101 base[LOCAL_ELEMS] = x;
102 return base;
104 unsigned int length = array.heap->length ();
105 if (length > i)
107 gcc_checking_assert (base == array.heap->address ());
108 base[i] = x;
109 return base;
111 else
113 gcc_checking_assert (i == length);
114 vec_safe_push (array.heap, x);
115 return array.heap->address ();
119 /* Add the subrtxes of X to worklist ARRAY, starting at END. Return the
120 number of elements added to the worklist. */
122 template <typename T>
123 size_t
124 generic_subrtx_iterator <T>::add_subrtxes_to_queue (array_type &array,
125 value_type *base,
126 size_t end, rtx_type x)
128 enum rtx_code code = GET_CODE (x);
129 const char *format = GET_RTX_FORMAT (code);
130 size_t orig_end = end;
131 if (__builtin_expect (INSN_P (x), false))
133 /* Put the pattern at the top of the queue, since that's what
134 we're likely to want most. It also allows for the SEQUENCE
135 code below. */
136 for (int i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; --i)
137 if (format[i] == 'e')
139 value_type subx = T::get_value (x->u.fld[i].rt_rtx);
140 if (__builtin_expect (end < LOCAL_ELEMS, true))
141 base[end++] = subx;
142 else
143 base = add_single_to_queue (array, base, end++, subx);
146 else
147 for (int i = 0; format[i]; ++i)
148 if (format[i] == 'e')
150 value_type subx = T::get_value (x->u.fld[i].rt_rtx);
151 if (__builtin_expect (end < LOCAL_ELEMS, true))
152 base[end++] = subx;
153 else
154 base = add_single_to_queue (array, base, end++, subx);
156 else if (format[i] == 'E')
158 unsigned int length = GET_NUM_ELEM (x->u.fld[i].rt_rtvec);
159 rtx *vec = x->u.fld[i].rt_rtvec->elem;
160 if (__builtin_expect (end + length <= LOCAL_ELEMS, true))
161 for (unsigned int j = 0; j < length; j++)
162 base[end++] = T::get_value (vec[j]);
163 else
164 for (unsigned int j = 0; j < length; j++)
165 base = add_single_to_queue (array, base, end++,
166 T::get_value (vec[j]));
167 if (code == SEQUENCE && end == length)
168 /* If the subrtxes of the sequence fill the entire array then
169 we know that no other parts of a containing insn are queued.
170 The caller is therefore iterating over the sequence as a
171 PATTERN (...), so we also want the patterns of the
172 subinstructions. */
173 for (unsigned int j = 0; j < length; j++)
175 typename T::rtx_type x = T::get_rtx (base[j]);
176 if (INSN_P (x))
177 base[j] = T::get_value (PATTERN (x));
180 return end - orig_end;
183 template <typename T>
184 void
185 generic_subrtx_iterator <T>::free_array (array_type &array)
187 vec_free (array.heap);
190 template <typename T>
191 const size_t generic_subrtx_iterator <T>::LOCAL_ELEMS;
193 template class generic_subrtx_iterator <const_rtx_accessor>;
194 template class generic_subrtx_iterator <rtx_var_accessor>;
195 template class generic_subrtx_iterator <rtx_ptr_accessor>;
197 /* Return 1 if the value of X is unstable
198 (would be different at a different point in the program).
199 The frame pointer, arg pointer, etc. are considered stable
200 (within one function) and so is anything marked `unchanging'. */
203 rtx_unstable_p (const_rtx x)
205 const RTX_CODE code = GET_CODE (x);
206 int i;
207 const char *fmt;
209 switch (code)
211 case MEM:
212 return !MEM_READONLY_P (x) || rtx_unstable_p (XEXP (x, 0));
214 case CONST:
215 CASE_CONST_ANY:
216 case SYMBOL_REF:
217 case LABEL_REF:
218 return 0;
220 case REG:
221 /* As in rtx_varies_p, we have to use the actual rtx, not reg number. */
222 if (x == frame_pointer_rtx || x == hard_frame_pointer_rtx
223 /* The arg pointer varies if it is not a fixed register. */
224 || (x == arg_pointer_rtx && fixed_regs[ARG_POINTER_REGNUM]))
225 return 0;
226 /* ??? When call-clobbered, the value is stable modulo the restore
227 that must happen after a call. This currently screws up local-alloc
228 into believing that the restore is not needed. */
229 if (!PIC_OFFSET_TABLE_REG_CALL_CLOBBERED && x == pic_offset_table_rtx)
230 return 0;
231 return 1;
233 case ASM_OPERANDS:
234 if (MEM_VOLATILE_P (x))
235 return 1;
237 /* Fall through. */
239 default:
240 break;
243 fmt = GET_RTX_FORMAT (code);
244 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
245 if (fmt[i] == 'e')
247 if (rtx_unstable_p (XEXP (x, i)))
248 return 1;
250 else if (fmt[i] == 'E')
252 int j;
253 for (j = 0; j < XVECLEN (x, i); j++)
254 if (rtx_unstable_p (XVECEXP (x, i, j)))
255 return 1;
258 return 0;
261 /* Return 1 if X has a value that can vary even between two
262 executions of the program. 0 means X can be compared reliably
263 against certain constants or near-constants.
264 FOR_ALIAS is nonzero if we are called from alias analysis; if it is
265 zero, we are slightly more conservative.
266 The frame pointer and the arg pointer are considered constant. */
268 bool
269 rtx_varies_p (const_rtx x, bool for_alias)
271 RTX_CODE code;
272 int i;
273 const char *fmt;
275 if (!x)
276 return 0;
278 code = GET_CODE (x);
279 switch (code)
281 case MEM:
282 return !MEM_READONLY_P (x) || rtx_varies_p (XEXP (x, 0), for_alias);
284 case CONST:
285 CASE_CONST_ANY:
286 case SYMBOL_REF:
287 case LABEL_REF:
288 return 0;
290 case REG:
291 /* Note that we have to test for the actual rtx used for the frame
292 and arg pointers and not just the register number in case we have
293 eliminated the frame and/or arg pointer and are using it
294 for pseudos. */
295 if (x == frame_pointer_rtx || x == hard_frame_pointer_rtx
296 /* The arg pointer varies if it is not a fixed register. */
297 || (x == arg_pointer_rtx && fixed_regs[ARG_POINTER_REGNUM]))
298 return 0;
299 if (x == pic_offset_table_rtx
300 /* ??? When call-clobbered, the value is stable modulo the restore
301 that must happen after a call. This currently screws up
302 local-alloc into believing that the restore is not needed, so we
303 must return 0 only if we are called from alias analysis. */
304 && (!PIC_OFFSET_TABLE_REG_CALL_CLOBBERED || for_alias))
305 return 0;
306 return 1;
308 case LO_SUM:
309 /* The operand 0 of a LO_SUM is considered constant
310 (in fact it is related specifically to operand 1)
311 during alias analysis. */
312 return (! for_alias && rtx_varies_p (XEXP (x, 0), for_alias))
313 || rtx_varies_p (XEXP (x, 1), for_alias);
315 case ASM_OPERANDS:
316 if (MEM_VOLATILE_P (x))
317 return 1;
319 /* Fall through. */
321 default:
322 break;
325 fmt = GET_RTX_FORMAT (code);
326 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
327 if (fmt[i] == 'e')
329 if (rtx_varies_p (XEXP (x, i), for_alias))
330 return 1;
332 else if (fmt[i] == 'E')
334 int j;
335 for (j = 0; j < XVECLEN (x, i); j++)
336 if (rtx_varies_p (XVECEXP (x, i, j), for_alias))
337 return 1;
340 return 0;
343 /* Compute an approximation for the offset between the register
344 FROM and TO for the current function, as it was at the start
345 of the routine. */
347 static poly_int64
348 get_initial_register_offset (int from, int to)
350 static const struct elim_table_t
352 const int from;
353 const int to;
354 } table[] = ELIMINABLE_REGS;
355 poly_int64 offset1, offset2;
356 unsigned int i, j;
358 if (to == from)
359 return 0;
361 /* It is not safe to call INITIAL_ELIMINATION_OFFSET
362 before the reload pass. We need to give at least
363 an estimation for the resulting frame size. */
364 if (! reload_completed)
366 offset1 = crtl->outgoing_args_size + get_frame_size ();
367 #if !STACK_GROWS_DOWNWARD
368 offset1 = - offset1;
369 #endif
370 if (to == STACK_POINTER_REGNUM)
371 return offset1;
372 else if (from == STACK_POINTER_REGNUM)
373 return - offset1;
374 else
375 return 0;
378 for (i = 0; i < ARRAY_SIZE (table); i++)
379 if (table[i].from == from)
381 if (table[i].to == to)
383 INITIAL_ELIMINATION_OFFSET (table[i].from, table[i].to,
384 offset1);
385 return offset1;
387 for (j = 0; j < ARRAY_SIZE (table); j++)
389 if (table[j].to == to
390 && table[j].from == table[i].to)
392 INITIAL_ELIMINATION_OFFSET (table[i].from, table[i].to,
393 offset1);
394 INITIAL_ELIMINATION_OFFSET (table[j].from, table[j].to,
395 offset2);
396 return offset1 + offset2;
398 if (table[j].from == to
399 && table[j].to == table[i].to)
401 INITIAL_ELIMINATION_OFFSET (table[i].from, table[i].to,
402 offset1);
403 INITIAL_ELIMINATION_OFFSET (table[j].from, table[j].to,
404 offset2);
405 return offset1 - offset2;
409 else if (table[i].to == from)
411 if (table[i].from == to)
413 INITIAL_ELIMINATION_OFFSET (table[i].from, table[i].to,
414 offset1);
415 return - offset1;
417 for (j = 0; j < ARRAY_SIZE (table); j++)
419 if (table[j].to == to
420 && table[j].from == table[i].from)
422 INITIAL_ELIMINATION_OFFSET (table[i].from, table[i].to,
423 offset1);
424 INITIAL_ELIMINATION_OFFSET (table[j].from, table[j].to,
425 offset2);
426 return - offset1 + offset2;
428 if (table[j].from == to
429 && table[j].to == table[i].from)
431 INITIAL_ELIMINATION_OFFSET (table[i].from, table[i].to,
432 offset1);
433 INITIAL_ELIMINATION_OFFSET (table[j].from, table[j].to,
434 offset2);
435 return - offset1 - offset2;
440 /* If the requested register combination was not found,
441 try a different more simple combination. */
442 if (from == ARG_POINTER_REGNUM)
443 return get_initial_register_offset (HARD_FRAME_POINTER_REGNUM, to);
444 else if (to == ARG_POINTER_REGNUM)
445 return get_initial_register_offset (from, HARD_FRAME_POINTER_REGNUM);
446 else if (from == HARD_FRAME_POINTER_REGNUM)
447 return get_initial_register_offset (FRAME_POINTER_REGNUM, to);
448 else if (to == HARD_FRAME_POINTER_REGNUM)
449 return get_initial_register_offset (from, FRAME_POINTER_REGNUM);
450 else
451 return 0;
454 /* Return nonzero if the use of X+OFFSET as an address in a MEM with SIZE
455 bytes can cause a trap. MODE is the mode of the MEM (not that of X) and
456 UNALIGNED_MEMS controls whether nonzero is returned for unaligned memory
457 references on strict alignment machines. */
459 static int
460 rtx_addr_can_trap_p_1 (const_rtx x, poly_int64 offset, poly_int64 size,
461 machine_mode mode, bool unaligned_mems)
463 enum rtx_code code = GET_CODE (x);
464 gcc_checking_assert (mode == BLKmode || known_size_p (size));
466 /* The offset must be a multiple of the mode size if we are considering
467 unaligned memory references on strict alignment machines. */
468 if (STRICT_ALIGNMENT && unaligned_mems && mode != BLKmode)
470 poly_int64 actual_offset = offset;
472 #ifdef SPARC_STACK_BOUNDARY_HACK
473 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
474 the real alignment of %sp. However, when it does this, the
475 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
476 if (SPARC_STACK_BOUNDARY_HACK
477 && (x == stack_pointer_rtx || x == hard_frame_pointer_rtx))
478 actual_offset -= STACK_POINTER_OFFSET;
479 #endif
481 if (!multiple_p (actual_offset, GET_MODE_SIZE (mode)))
482 return 1;
485 switch (code)
487 case SYMBOL_REF:
488 if (SYMBOL_REF_WEAK (x))
489 return 1;
490 if (!CONSTANT_POOL_ADDRESS_P (x) && !SYMBOL_REF_FUNCTION_P (x))
492 tree decl;
493 poly_int64 decl_size;
495 if (maybe_lt (offset, 0))
496 return 1;
497 if (!known_size_p (size))
498 return maybe_ne (offset, 0);
500 /* If the size of the access or of the symbol is unknown,
501 assume the worst. */
502 decl = SYMBOL_REF_DECL (x);
504 /* Else check that the access is in bounds. TODO: restructure
505 expr_size/tree_expr_size/int_expr_size and just use the latter. */
506 if (!decl)
507 decl_size = -1;
508 else if (DECL_P (decl) && DECL_SIZE_UNIT (decl))
510 if (!poly_int_tree_p (DECL_SIZE_UNIT (decl), &decl_size))
511 decl_size = -1;
513 else if (TREE_CODE (decl) == STRING_CST)
514 decl_size = TREE_STRING_LENGTH (decl);
515 else if (TYPE_SIZE_UNIT (TREE_TYPE (decl)))
516 decl_size = int_size_in_bytes (TREE_TYPE (decl));
517 else
518 decl_size = -1;
520 return (!known_size_p (decl_size) || known_eq (decl_size, 0)
521 ? maybe_ne (offset, 0)
522 : maybe_gt (offset + size, decl_size));
525 return 0;
527 case LABEL_REF:
528 return 0;
530 case REG:
531 /* Stack references are assumed not to trap, but we need to deal with
532 nonsensical offsets. */
533 if (x == frame_pointer_rtx || x == hard_frame_pointer_rtx
534 || x == stack_pointer_rtx
535 /* The arg pointer varies if it is not a fixed register. */
536 || (x == arg_pointer_rtx && fixed_regs[ARG_POINTER_REGNUM]))
538 #ifdef RED_ZONE_SIZE
539 poly_int64 red_zone_size = RED_ZONE_SIZE;
540 #else
541 poly_int64 red_zone_size = 0;
542 #endif
543 poly_int64 stack_boundary = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
544 poly_int64 low_bound, high_bound;
546 if (!known_size_p (size))
547 return 1;
549 if (x == frame_pointer_rtx)
551 if (FRAME_GROWS_DOWNWARD)
553 high_bound = targetm.starting_frame_offset ();
554 low_bound = high_bound - get_frame_size ();
556 else
558 low_bound = targetm.starting_frame_offset ();
559 high_bound = low_bound + get_frame_size ();
562 else if (x == hard_frame_pointer_rtx)
564 poly_int64 sp_offset
565 = get_initial_register_offset (STACK_POINTER_REGNUM,
566 HARD_FRAME_POINTER_REGNUM);
567 poly_int64 ap_offset
568 = get_initial_register_offset (ARG_POINTER_REGNUM,
569 HARD_FRAME_POINTER_REGNUM);
571 #if STACK_GROWS_DOWNWARD
572 low_bound = sp_offset - red_zone_size - stack_boundary;
573 high_bound = ap_offset
574 + FIRST_PARM_OFFSET (current_function_decl)
575 #if !ARGS_GROW_DOWNWARD
576 + crtl->args.size
577 #endif
578 + stack_boundary;
579 #else
580 high_bound = sp_offset + red_zone_size + stack_boundary;
581 low_bound = ap_offset
582 + FIRST_PARM_OFFSET (current_function_decl)
583 #if ARGS_GROW_DOWNWARD
584 - crtl->args.size
585 #endif
586 - stack_boundary;
587 #endif
589 else if (x == stack_pointer_rtx)
591 poly_int64 ap_offset
592 = get_initial_register_offset (ARG_POINTER_REGNUM,
593 STACK_POINTER_REGNUM);
595 #if STACK_GROWS_DOWNWARD
596 low_bound = - red_zone_size - stack_boundary;
597 high_bound = ap_offset
598 + FIRST_PARM_OFFSET (current_function_decl)
599 #if !ARGS_GROW_DOWNWARD
600 + crtl->args.size
601 #endif
602 + stack_boundary;
603 #else
604 high_bound = red_zone_size + stack_boundary;
605 low_bound = ap_offset
606 + FIRST_PARM_OFFSET (current_function_decl)
607 #if ARGS_GROW_DOWNWARD
608 - crtl->args.size
609 #endif
610 - stack_boundary;
611 #endif
613 else
615 /* We assume that accesses are safe to at least the
616 next stack boundary.
617 Examples are varargs and __builtin_return_address. */
618 #if ARGS_GROW_DOWNWARD
619 high_bound = FIRST_PARM_OFFSET (current_function_decl)
620 + stack_boundary;
621 low_bound = FIRST_PARM_OFFSET (current_function_decl)
622 - crtl->args.size - stack_boundary;
623 #else
624 low_bound = FIRST_PARM_OFFSET (current_function_decl)
625 - stack_boundary;
626 high_bound = FIRST_PARM_OFFSET (current_function_decl)
627 + crtl->args.size + stack_boundary;
628 #endif
631 if (known_ge (offset, low_bound)
632 && known_le (offset, high_bound - size))
633 return 0;
634 return 1;
636 /* All of the virtual frame registers are stack references. */
637 if (REGNO (x) >= FIRST_VIRTUAL_REGISTER
638 && REGNO (x) <= LAST_VIRTUAL_REGISTER)
639 return 0;
640 return 1;
642 case CONST:
643 return rtx_addr_can_trap_p_1 (XEXP (x, 0), offset, size,
644 mode, unaligned_mems);
646 case PLUS:
647 /* An address is assumed not to trap if:
648 - it is the pic register plus a const unspec without offset. */
649 if (XEXP (x, 0) == pic_offset_table_rtx
650 && GET_CODE (XEXP (x, 1)) == CONST
651 && GET_CODE (XEXP (XEXP (x, 1), 0)) == UNSPEC
652 && known_eq (offset, 0))
653 return 0;
655 /* - or it is an address that can't trap plus a constant integer. */
656 if (CONST_INT_P (XEXP (x, 1))
657 && !rtx_addr_can_trap_p_1 (XEXP (x, 0), offset + INTVAL (XEXP (x, 1)),
658 size, mode, unaligned_mems))
659 return 0;
661 return 1;
663 case LO_SUM:
664 case PRE_MODIFY:
665 return rtx_addr_can_trap_p_1 (XEXP (x, 1), offset, size,
666 mode, unaligned_mems);
668 case PRE_DEC:
669 case PRE_INC:
670 case POST_DEC:
671 case POST_INC:
672 case POST_MODIFY:
673 return rtx_addr_can_trap_p_1 (XEXP (x, 0), offset, size,
674 mode, unaligned_mems);
676 default:
677 break;
680 /* If it isn't one of the case above, it can cause a trap. */
681 return 1;
684 /* Return nonzero if the use of X as an address in a MEM can cause a trap. */
687 rtx_addr_can_trap_p (const_rtx x)
689 return rtx_addr_can_trap_p_1 (x, 0, -1, BLKmode, false);
692 /* Return true if X contains a MEM subrtx. */
694 bool
695 contains_mem_rtx_p (rtx x)
697 subrtx_iterator::array_type array;
698 FOR_EACH_SUBRTX (iter, array, x, ALL)
699 if (MEM_P (*iter))
700 return true;
702 return false;
705 /* Return true if X is an address that is known to not be zero. */
707 bool
708 nonzero_address_p (const_rtx x)
710 const enum rtx_code code = GET_CODE (x);
712 switch (code)
714 case SYMBOL_REF:
715 return flag_delete_null_pointer_checks && !SYMBOL_REF_WEAK (x);
717 case LABEL_REF:
718 return true;
720 case REG:
721 /* As in rtx_varies_p, we have to use the actual rtx, not reg number. */
722 if (x == frame_pointer_rtx || x == hard_frame_pointer_rtx
723 || x == stack_pointer_rtx
724 || (x == arg_pointer_rtx && fixed_regs[ARG_POINTER_REGNUM]))
725 return true;
726 /* All of the virtual frame registers are stack references. */
727 if (REGNO (x) >= FIRST_VIRTUAL_REGISTER
728 && REGNO (x) <= LAST_VIRTUAL_REGISTER)
729 return true;
730 return false;
732 case CONST:
733 return nonzero_address_p (XEXP (x, 0));
735 case PLUS:
736 /* Handle PIC references. */
737 if (XEXP (x, 0) == pic_offset_table_rtx
738 && CONSTANT_P (XEXP (x, 1)))
739 return true;
740 return false;
742 case PRE_MODIFY:
743 /* Similar to the above; allow positive offsets. Further, since
744 auto-inc is only allowed in memories, the register must be a
745 pointer. */
746 if (CONST_INT_P (XEXP (x, 1))
747 && INTVAL (XEXP (x, 1)) > 0)
748 return true;
749 return nonzero_address_p (XEXP (x, 0));
751 case PRE_INC:
752 /* Similarly. Further, the offset is always positive. */
753 return true;
755 case PRE_DEC:
756 case POST_DEC:
757 case POST_INC:
758 case POST_MODIFY:
759 return nonzero_address_p (XEXP (x, 0));
761 case LO_SUM:
762 return nonzero_address_p (XEXP (x, 1));
764 default:
765 break;
768 /* If it isn't one of the case above, might be zero. */
769 return false;
772 /* Return 1 if X refers to a memory location whose address
773 cannot be compared reliably with constant addresses,
774 or if X refers to a BLKmode memory object.
775 FOR_ALIAS is nonzero if we are called from alias analysis; if it is
776 zero, we are slightly more conservative. */
778 bool
779 rtx_addr_varies_p (const_rtx x, bool for_alias)
781 enum rtx_code code;
782 int i;
783 const char *fmt;
785 if (x == 0)
786 return 0;
788 code = GET_CODE (x);
789 if (code == MEM)
790 return GET_MODE (x) == BLKmode || rtx_varies_p (XEXP (x, 0), for_alias);
792 fmt = GET_RTX_FORMAT (code);
793 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
794 if (fmt[i] == 'e')
796 if (rtx_addr_varies_p (XEXP (x, i), for_alias))
797 return 1;
799 else if (fmt[i] == 'E')
801 int j;
802 for (j = 0; j < XVECLEN (x, i); j++)
803 if (rtx_addr_varies_p (XVECEXP (x, i, j), for_alias))
804 return 1;
806 return 0;
809 /* Return the CALL in X if there is one. */
812 get_call_rtx_from (rtx x)
814 if (INSN_P (x))
815 x = PATTERN (x);
816 if (GET_CODE (x) == PARALLEL)
817 x = XVECEXP (x, 0, 0);
818 if (GET_CODE (x) == SET)
819 x = SET_SRC (x);
820 if (GET_CODE (x) == CALL && MEM_P (XEXP (x, 0)))
821 return x;
822 return NULL_RTX;
825 /* Return the value of the integer term in X, if one is apparent;
826 otherwise return 0.
827 Only obvious integer terms are detected.
828 This is used in cse.c with the `related_value' field. */
830 HOST_WIDE_INT
831 get_integer_term (const_rtx x)
833 if (GET_CODE (x) == CONST)
834 x = XEXP (x, 0);
836 if (GET_CODE (x) == MINUS
837 && CONST_INT_P (XEXP (x, 1)))
838 return - INTVAL (XEXP (x, 1));
839 if (GET_CODE (x) == PLUS
840 && CONST_INT_P (XEXP (x, 1)))
841 return INTVAL (XEXP (x, 1));
842 return 0;
845 /* If X is a constant, return the value sans apparent integer term;
846 otherwise return 0.
847 Only obvious integer terms are detected. */
850 get_related_value (const_rtx x)
852 if (GET_CODE (x) != CONST)
853 return 0;
854 x = XEXP (x, 0);
855 if (GET_CODE (x) == PLUS
856 && CONST_INT_P (XEXP (x, 1)))
857 return XEXP (x, 0);
858 else if (GET_CODE (x) == MINUS
859 && CONST_INT_P (XEXP (x, 1)))
860 return XEXP (x, 0);
861 return 0;
864 /* Return true if SYMBOL is a SYMBOL_REF and OFFSET + SYMBOL points
865 to somewhere in the same object or object_block as SYMBOL. */
867 bool
868 offset_within_block_p (const_rtx symbol, HOST_WIDE_INT offset)
870 tree decl;
872 if (GET_CODE (symbol) != SYMBOL_REF)
873 return false;
875 if (offset == 0)
876 return true;
878 if (offset > 0)
880 if (CONSTANT_POOL_ADDRESS_P (symbol)
881 && offset < (int) GET_MODE_SIZE (get_pool_mode (symbol)))
882 return true;
884 decl = SYMBOL_REF_DECL (symbol);
885 if (decl && offset < int_size_in_bytes (TREE_TYPE (decl)))
886 return true;
889 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol)
890 && SYMBOL_REF_BLOCK (symbol)
891 && SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0
892 && ((unsigned HOST_WIDE_INT) offset + SYMBOL_REF_BLOCK_OFFSET (symbol)
893 < (unsigned HOST_WIDE_INT) SYMBOL_REF_BLOCK (symbol)->size))
894 return true;
896 return false;
899 /* Split X into a base and a constant offset, storing them in *BASE_OUT
900 and *OFFSET_OUT respectively. */
902 void
903 split_const (rtx x, rtx *base_out, rtx *offset_out)
905 if (GET_CODE (x) == CONST)
907 x = XEXP (x, 0);
908 if (GET_CODE (x) == PLUS && CONST_INT_P (XEXP (x, 1)))
910 *base_out = XEXP (x, 0);
911 *offset_out = XEXP (x, 1);
912 return;
915 *base_out = x;
916 *offset_out = const0_rtx;
919 /* Express integer value X as some value Y plus a polynomial offset,
920 where Y is either const0_rtx, X or something within X (as opposed
921 to a new rtx). Return the Y and store the offset in *OFFSET_OUT. */
924 strip_offset (rtx x, poly_int64_pod *offset_out)
926 rtx base = const0_rtx;
927 rtx test = x;
928 if (GET_CODE (test) == CONST)
929 test = XEXP (test, 0);
930 if (GET_CODE (test) == PLUS)
932 base = XEXP (test, 0);
933 test = XEXP (test, 1);
935 if (poly_int_rtx_p (test, offset_out))
936 return base;
937 *offset_out = 0;
938 return x;
941 /* Return the argument size in REG_ARGS_SIZE note X. */
943 poly_int64
944 get_args_size (const_rtx x)
946 gcc_checking_assert (REG_NOTE_KIND (x) == REG_ARGS_SIZE);
947 return rtx_to_poly_int64 (XEXP (x, 0));
950 /* Return the number of places FIND appears within X. If COUNT_DEST is
951 zero, we do not count occurrences inside the destination of a SET. */
954 count_occurrences (const_rtx x, const_rtx find, int count_dest)
956 int i, j;
957 enum rtx_code code;
958 const char *format_ptr;
959 int count;
961 if (x == find)
962 return 1;
964 code = GET_CODE (x);
966 switch (code)
968 case REG:
969 CASE_CONST_ANY:
970 case SYMBOL_REF:
971 case CODE_LABEL:
972 case PC:
973 case CC0:
974 return 0;
976 case EXPR_LIST:
977 count = count_occurrences (XEXP (x, 0), find, count_dest);
978 if (XEXP (x, 1))
979 count += count_occurrences (XEXP (x, 1), find, count_dest);
980 return count;
982 case MEM:
983 if (MEM_P (find) && rtx_equal_p (x, find))
984 return 1;
985 break;
987 case SET:
988 if (SET_DEST (x) == find && ! count_dest)
989 return count_occurrences (SET_SRC (x), find, count_dest);
990 break;
992 default:
993 break;
996 format_ptr = GET_RTX_FORMAT (code);
997 count = 0;
999 for (i = 0; i < GET_RTX_LENGTH (code); i++)
1001 switch (*format_ptr++)
1003 case 'e':
1004 count += count_occurrences (XEXP (x, i), find, count_dest);
1005 break;
1007 case 'E':
1008 for (j = 0; j < XVECLEN (x, i); j++)
1009 count += count_occurrences (XVECEXP (x, i, j), find, count_dest);
1010 break;
1013 return count;
1017 /* Return TRUE if OP is a register or subreg of a register that
1018 holds an unsigned quantity. Otherwise, return FALSE. */
1020 bool
1021 unsigned_reg_p (rtx op)
1023 if (REG_P (op)
1024 && REG_EXPR (op)
1025 && TYPE_UNSIGNED (TREE_TYPE (REG_EXPR (op))))
1026 return true;
1028 if (GET_CODE (op) == SUBREG
1029 && SUBREG_PROMOTED_SIGN (op))
1030 return true;
1032 return false;
1036 /* Nonzero if register REG appears somewhere within IN.
1037 Also works if REG is not a register; in this case it checks
1038 for a subexpression of IN that is Lisp "equal" to REG. */
1041 reg_mentioned_p (const_rtx reg, const_rtx in)
1043 const char *fmt;
1044 int i;
1045 enum rtx_code code;
1047 if (in == 0)
1048 return 0;
1050 if (reg == in)
1051 return 1;
1053 if (GET_CODE (in) == LABEL_REF)
1054 return reg == label_ref_label (in);
1056 code = GET_CODE (in);
1058 switch (code)
1060 /* Compare registers by number. */
1061 case REG:
1062 return REG_P (reg) && REGNO (in) == REGNO (reg);
1064 /* These codes have no constituent expressions
1065 and are unique. */
1066 case SCRATCH:
1067 case CC0:
1068 case PC:
1069 return 0;
1071 CASE_CONST_ANY:
1072 /* These are kept unique for a given value. */
1073 return 0;
1075 default:
1076 break;
1079 if (GET_CODE (reg) == code && rtx_equal_p (reg, in))
1080 return 1;
1082 fmt = GET_RTX_FORMAT (code);
1084 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1086 if (fmt[i] == 'E')
1088 int j;
1089 for (j = XVECLEN (in, i) - 1; j >= 0; j--)
1090 if (reg_mentioned_p (reg, XVECEXP (in, i, j)))
1091 return 1;
1093 else if (fmt[i] == 'e'
1094 && reg_mentioned_p (reg, XEXP (in, i)))
1095 return 1;
1097 return 0;
1100 /* Return 1 if in between BEG and END, exclusive of BEG and END, there is
1101 no CODE_LABEL insn. */
1104 no_labels_between_p (const rtx_insn *beg, const rtx_insn *end)
1106 rtx_insn *p;
1107 if (beg == end)
1108 return 0;
1109 for (p = NEXT_INSN (beg); p != end; p = NEXT_INSN (p))
1110 if (LABEL_P (p))
1111 return 0;
1112 return 1;
1115 /* Nonzero if register REG is used in an insn between
1116 FROM_INSN and TO_INSN (exclusive of those two). */
1119 reg_used_between_p (const_rtx reg, const rtx_insn *from_insn,
1120 const rtx_insn *to_insn)
1122 rtx_insn *insn;
1124 if (from_insn == to_insn)
1125 return 0;
1127 for (insn = NEXT_INSN (from_insn); insn != to_insn; insn = NEXT_INSN (insn))
1128 if (NONDEBUG_INSN_P (insn)
1129 && (reg_overlap_mentioned_p (reg, PATTERN (insn))
1130 || (CALL_P (insn) && find_reg_fusage (insn, USE, reg))))
1131 return 1;
1132 return 0;
1135 /* Nonzero if the old value of X, a register, is referenced in BODY. If X
1136 is entirely replaced by a new value and the only use is as a SET_DEST,
1137 we do not consider it a reference. */
1140 reg_referenced_p (const_rtx x, const_rtx body)
1142 int i;
1144 switch (GET_CODE (body))
1146 case SET:
1147 if (reg_overlap_mentioned_p (x, SET_SRC (body)))
1148 return 1;
1150 /* If the destination is anything other than CC0, PC, a REG or a SUBREG
1151 of a REG that occupies all of the REG, the insn references X if
1152 it is mentioned in the destination. */
1153 if (GET_CODE (SET_DEST (body)) != CC0
1154 && GET_CODE (SET_DEST (body)) != PC
1155 && !REG_P (SET_DEST (body))
1156 && ! (GET_CODE (SET_DEST (body)) == SUBREG
1157 && REG_P (SUBREG_REG (SET_DEST (body)))
1158 && !read_modify_subreg_p (SET_DEST (body)))
1159 && reg_overlap_mentioned_p (x, SET_DEST (body)))
1160 return 1;
1161 return 0;
1163 case ASM_OPERANDS:
1164 for (i = ASM_OPERANDS_INPUT_LENGTH (body) - 1; i >= 0; i--)
1165 if (reg_overlap_mentioned_p (x, ASM_OPERANDS_INPUT (body, i)))
1166 return 1;
1167 return 0;
1169 case CALL:
1170 case USE:
1171 case IF_THEN_ELSE:
1172 return reg_overlap_mentioned_p (x, body);
1174 case TRAP_IF:
1175 return reg_overlap_mentioned_p (x, TRAP_CONDITION (body));
1177 case PREFETCH:
1178 return reg_overlap_mentioned_p (x, XEXP (body, 0));
1180 case UNSPEC:
1181 case UNSPEC_VOLATILE:
1182 for (i = XVECLEN (body, 0) - 1; i >= 0; i--)
1183 if (reg_overlap_mentioned_p (x, XVECEXP (body, 0, i)))
1184 return 1;
1185 return 0;
1187 case PARALLEL:
1188 for (i = XVECLEN (body, 0) - 1; i >= 0; i--)
1189 if (reg_referenced_p (x, XVECEXP (body, 0, i)))
1190 return 1;
1191 return 0;
1193 case CLOBBER:
1194 if (MEM_P (XEXP (body, 0)))
1195 if (reg_overlap_mentioned_p (x, XEXP (XEXP (body, 0), 0)))
1196 return 1;
1197 return 0;
1199 case COND_EXEC:
1200 if (reg_overlap_mentioned_p (x, COND_EXEC_TEST (body)))
1201 return 1;
1202 return reg_referenced_p (x, COND_EXEC_CODE (body));
1204 default:
1205 return 0;
1209 /* Nonzero if register REG is set or clobbered in an insn between
1210 FROM_INSN and TO_INSN (exclusive of those two). */
1213 reg_set_between_p (const_rtx reg, const rtx_insn *from_insn,
1214 const rtx_insn *to_insn)
1216 const rtx_insn *insn;
1218 if (from_insn == to_insn)
1219 return 0;
1221 for (insn = NEXT_INSN (from_insn); insn != to_insn; insn = NEXT_INSN (insn))
1222 if (INSN_P (insn) && reg_set_p (reg, insn))
1223 return 1;
1224 return 0;
1227 /* Return true if REG is set or clobbered inside INSN. */
1230 reg_set_p (const_rtx reg, const_rtx insn)
1232 /* After delay slot handling, call and branch insns might be in a
1233 sequence. Check all the elements there. */
1234 if (INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
1236 for (int i = 0; i < XVECLEN (PATTERN (insn), 0); ++i)
1237 if (reg_set_p (reg, XVECEXP (PATTERN (insn), 0, i)))
1238 return true;
1240 return false;
1243 /* We can be passed an insn or part of one. If we are passed an insn,
1244 check if a side-effect of the insn clobbers REG. */
1245 if (INSN_P (insn)
1246 && (FIND_REG_INC_NOTE (insn, reg)
1247 || (CALL_P (insn)
1248 && ((REG_P (reg)
1249 && REGNO (reg) < FIRST_PSEUDO_REGISTER
1250 && overlaps_hard_reg_set_p (regs_invalidated_by_call,
1251 GET_MODE (reg), REGNO (reg)))
1252 || MEM_P (reg)
1253 || find_reg_fusage (insn, CLOBBER, reg)))))
1254 return true;
1256 /* There are no REG_INC notes for SP autoinc. */
1257 if (reg == stack_pointer_rtx && INSN_P (insn))
1259 subrtx_var_iterator::array_type array;
1260 FOR_EACH_SUBRTX_VAR (iter, array, PATTERN (insn), NONCONST)
1262 rtx mem = *iter;
1263 if (mem
1264 && MEM_P (mem)
1265 && GET_RTX_CLASS (GET_CODE (XEXP (mem, 0))) == RTX_AUTOINC)
1267 if (XEXP (XEXP (mem, 0), 0) == stack_pointer_rtx)
1268 return true;
1269 iter.skip_subrtxes ();
1274 return set_of (reg, insn) != NULL_RTX;
1277 /* Similar to reg_set_between_p, but check all registers in X. Return 0
1278 only if none of them are modified between START and END. Return 1 if
1279 X contains a MEM; this routine does use memory aliasing. */
1282 modified_between_p (const_rtx x, const rtx_insn *start, const rtx_insn *end)
1284 const enum rtx_code code = GET_CODE (x);
1285 const char *fmt;
1286 int i, j;
1287 rtx_insn *insn;
1289 if (start == end)
1290 return 0;
1292 switch (code)
1294 CASE_CONST_ANY:
1295 case CONST:
1296 case SYMBOL_REF:
1297 case LABEL_REF:
1298 return 0;
1300 case PC:
1301 case CC0:
1302 return 1;
1304 case MEM:
1305 if (modified_between_p (XEXP (x, 0), start, end))
1306 return 1;
1307 if (MEM_READONLY_P (x))
1308 return 0;
1309 for (insn = NEXT_INSN (start); insn != end; insn = NEXT_INSN (insn))
1310 if (memory_modified_in_insn_p (x, insn))
1311 return 1;
1312 return 0;
1314 case REG:
1315 return reg_set_between_p (x, start, end);
1317 default:
1318 break;
1321 fmt = GET_RTX_FORMAT (code);
1322 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1324 if (fmt[i] == 'e' && modified_between_p (XEXP (x, i), start, end))
1325 return 1;
1327 else if (fmt[i] == 'E')
1328 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
1329 if (modified_between_p (XVECEXP (x, i, j), start, end))
1330 return 1;
1333 return 0;
1336 /* Similar to reg_set_p, but check all registers in X. Return 0 only if none
1337 of them are modified in INSN. Return 1 if X contains a MEM; this routine
1338 does use memory aliasing. */
1341 modified_in_p (const_rtx x, const_rtx insn)
1343 const enum rtx_code code = GET_CODE (x);
1344 const char *fmt;
1345 int i, j;
1347 switch (code)
1349 CASE_CONST_ANY:
1350 case CONST:
1351 case SYMBOL_REF:
1352 case LABEL_REF:
1353 return 0;
1355 case PC:
1356 case CC0:
1357 return 1;
1359 case MEM:
1360 if (modified_in_p (XEXP (x, 0), insn))
1361 return 1;
1362 if (MEM_READONLY_P (x))
1363 return 0;
1364 if (memory_modified_in_insn_p (x, insn))
1365 return 1;
1366 return 0;
1368 case REG:
1369 return reg_set_p (x, insn);
1371 default:
1372 break;
1375 fmt = GET_RTX_FORMAT (code);
1376 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1378 if (fmt[i] == 'e' && modified_in_p (XEXP (x, i), insn))
1379 return 1;
1381 else if (fmt[i] == 'E')
1382 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
1383 if (modified_in_p (XVECEXP (x, i, j), insn))
1384 return 1;
1387 return 0;
1390 /* Return true if X is a SUBREG and if storing a value to X would
1391 preserve some of its SUBREG_REG. For example, on a normal 32-bit
1392 target, using a SUBREG to store to one half of a DImode REG would
1393 preserve the other half. */
1395 bool
1396 read_modify_subreg_p (const_rtx x)
1398 if (GET_CODE (x) != SUBREG)
1399 return false;
1400 poly_uint64 isize = GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)));
1401 poly_uint64 osize = GET_MODE_SIZE (GET_MODE (x));
1402 poly_uint64 regsize = REGMODE_NATURAL_SIZE (GET_MODE (SUBREG_REG (x)));
1403 /* The inner and outer modes of a subreg must be ordered, so that we
1404 can tell whether they're paradoxical or partial. */
1405 gcc_checking_assert (ordered_p (isize, osize));
1406 return (maybe_gt (isize, osize) && maybe_gt (isize, regsize));
1409 /* Helper function for set_of. */
1410 struct set_of_data
1412 const_rtx found;
1413 const_rtx pat;
1416 static void
1417 set_of_1 (rtx x, const_rtx pat, void *data1)
1419 struct set_of_data *const data = (struct set_of_data *) (data1);
1420 if (rtx_equal_p (x, data->pat)
1421 || (!MEM_P (x) && reg_overlap_mentioned_p (data->pat, x)))
1422 data->found = pat;
1425 /* Give an INSN, return a SET or CLOBBER expression that does modify PAT
1426 (either directly or via STRICT_LOW_PART and similar modifiers). */
1427 const_rtx
1428 set_of (const_rtx pat, const_rtx insn)
1430 struct set_of_data data;
1431 data.found = NULL_RTX;
1432 data.pat = pat;
1433 note_stores (INSN_P (insn) ? PATTERN (insn) : insn, set_of_1, &data);
1434 return data.found;
1437 /* Add all hard register in X to *PSET. */
1438 void
1439 find_all_hard_regs (const_rtx x, HARD_REG_SET *pset)
1441 subrtx_iterator::array_type array;
1442 FOR_EACH_SUBRTX (iter, array, x, NONCONST)
1444 const_rtx x = *iter;
1445 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
1446 add_to_hard_reg_set (pset, GET_MODE (x), REGNO (x));
1450 /* This function, called through note_stores, collects sets and
1451 clobbers of hard registers in a HARD_REG_SET, which is pointed to
1452 by DATA. */
1453 void
1454 record_hard_reg_sets (rtx x, const_rtx pat ATTRIBUTE_UNUSED, void *data)
1456 HARD_REG_SET *pset = (HARD_REG_SET *)data;
1457 if (REG_P (x) && HARD_REGISTER_P (x))
1458 add_to_hard_reg_set (pset, GET_MODE (x), REGNO (x));
1461 /* Examine INSN, and compute the set of hard registers written by it.
1462 Store it in *PSET. Should only be called after reload. */
1463 void
1464 find_all_hard_reg_sets (const rtx_insn *insn, HARD_REG_SET *pset, bool implicit)
1466 rtx link;
1468 CLEAR_HARD_REG_SET (*pset);
1469 note_stores (PATTERN (insn), record_hard_reg_sets, pset);
1470 if (CALL_P (insn))
1472 if (implicit)
1473 IOR_HARD_REG_SET (*pset, call_used_reg_set);
1475 for (link = CALL_INSN_FUNCTION_USAGE (insn); link; link = XEXP (link, 1))
1476 record_hard_reg_sets (XEXP (link, 0), NULL, pset);
1478 for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
1479 if (REG_NOTE_KIND (link) == REG_INC)
1480 record_hard_reg_sets (XEXP (link, 0), NULL, pset);
1483 /* Like record_hard_reg_sets, but called through note_uses. */
1484 void
1485 record_hard_reg_uses (rtx *px, void *data)
1487 find_all_hard_regs (*px, (HARD_REG_SET *) data);
1490 /* Given an INSN, return a SET expression if this insn has only a single SET.
1491 It may also have CLOBBERs, USEs, or SET whose output
1492 will not be used, which we ignore. */
1495 single_set_2 (const rtx_insn *insn, const_rtx pat)
1497 rtx set = NULL;
1498 int set_verified = 1;
1499 int i;
1501 if (GET_CODE (pat) == PARALLEL)
1503 for (i = 0; i < XVECLEN (pat, 0); i++)
1505 rtx sub = XVECEXP (pat, 0, i);
1506 switch (GET_CODE (sub))
1508 case USE:
1509 case CLOBBER:
1510 break;
1512 case SET:
1513 /* We can consider insns having multiple sets, where all
1514 but one are dead as single set insns. In common case
1515 only single set is present in the pattern so we want
1516 to avoid checking for REG_UNUSED notes unless necessary.
1518 When we reach set first time, we just expect this is
1519 the single set we are looking for and only when more
1520 sets are found in the insn, we check them. */
1521 if (!set_verified)
1523 if (find_reg_note (insn, REG_UNUSED, SET_DEST (set))
1524 && !side_effects_p (set))
1525 set = NULL;
1526 else
1527 set_verified = 1;
1529 if (!set)
1530 set = sub, set_verified = 0;
1531 else if (!find_reg_note (insn, REG_UNUSED, SET_DEST (sub))
1532 || side_effects_p (sub))
1533 return NULL_RTX;
1534 break;
1536 default:
1537 return NULL_RTX;
1541 return set;
1544 /* Given an INSN, return nonzero if it has more than one SET, else return
1545 zero. */
1548 multiple_sets (const_rtx insn)
1550 int found;
1551 int i;
1553 /* INSN must be an insn. */
1554 if (! INSN_P (insn))
1555 return 0;
1557 /* Only a PARALLEL can have multiple SETs. */
1558 if (GET_CODE (PATTERN (insn)) == PARALLEL)
1560 for (i = 0, found = 0; i < XVECLEN (PATTERN (insn), 0); i++)
1561 if (GET_CODE (XVECEXP (PATTERN (insn), 0, i)) == SET)
1563 /* If we have already found a SET, then return now. */
1564 if (found)
1565 return 1;
1566 else
1567 found = 1;
1571 /* Either zero or one SET. */
1572 return 0;
1575 /* Return nonzero if the destination of SET equals the source
1576 and there are no side effects. */
1579 set_noop_p (const_rtx set)
1581 rtx src = SET_SRC (set);
1582 rtx dst = SET_DEST (set);
1584 if (dst == pc_rtx && src == pc_rtx)
1585 return 1;
1587 if (MEM_P (dst) && MEM_P (src))
1588 return rtx_equal_p (dst, src) && !side_effects_p (dst);
1590 if (GET_CODE (dst) == ZERO_EXTRACT)
1591 return rtx_equal_p (XEXP (dst, 0), src)
1592 && !BITS_BIG_ENDIAN && XEXP (dst, 2) == const0_rtx
1593 && !side_effects_p (src);
1595 if (GET_CODE (dst) == STRICT_LOW_PART)
1596 dst = XEXP (dst, 0);
1598 if (GET_CODE (src) == SUBREG && GET_CODE (dst) == SUBREG)
1600 if (maybe_ne (SUBREG_BYTE (src), SUBREG_BYTE (dst)))
1601 return 0;
1602 src = SUBREG_REG (src);
1603 dst = SUBREG_REG (dst);
1606 /* It is a NOOP if destination overlaps with selected src vector
1607 elements. */
1608 if (GET_CODE (src) == VEC_SELECT
1609 && REG_P (XEXP (src, 0)) && REG_P (dst)
1610 && HARD_REGISTER_P (XEXP (src, 0))
1611 && HARD_REGISTER_P (dst))
1613 int i;
1614 rtx par = XEXP (src, 1);
1615 rtx src0 = XEXP (src, 0);
1616 int c0 = INTVAL (XVECEXP (par, 0, 0));
1617 HOST_WIDE_INT offset = GET_MODE_UNIT_SIZE (GET_MODE (src0)) * c0;
1619 for (i = 1; i < XVECLEN (par, 0); i++)
1620 if (INTVAL (XVECEXP (par, 0, i)) != c0 + i)
1621 return 0;
1622 return
1623 simplify_subreg_regno (REGNO (src0), GET_MODE (src0),
1624 offset, GET_MODE (dst)) == (int) REGNO (dst);
1627 return (REG_P (src) && REG_P (dst)
1628 && REGNO (src) == REGNO (dst));
1631 /* Return nonzero if an insn consists only of SETs, each of which only sets a
1632 value to itself. */
1635 noop_move_p (const rtx_insn *insn)
1637 rtx pat = PATTERN (insn);
1639 if (INSN_CODE (insn) == NOOP_MOVE_INSN_CODE)
1640 return 1;
1642 /* Insns carrying these notes are useful later on. */
1643 if (find_reg_note (insn, REG_EQUAL, NULL_RTX))
1644 return 0;
1646 /* Check the code to be executed for COND_EXEC. */
1647 if (GET_CODE (pat) == COND_EXEC)
1648 pat = COND_EXEC_CODE (pat);
1650 if (GET_CODE (pat) == SET && set_noop_p (pat))
1651 return 1;
1653 if (GET_CODE (pat) == PARALLEL)
1655 int i;
1656 /* If nothing but SETs of registers to themselves,
1657 this insn can also be deleted. */
1658 for (i = 0; i < XVECLEN (pat, 0); i++)
1660 rtx tem = XVECEXP (pat, 0, i);
1662 if (GET_CODE (tem) == USE
1663 || GET_CODE (tem) == CLOBBER)
1664 continue;
1666 if (GET_CODE (tem) != SET || ! set_noop_p (tem))
1667 return 0;
1670 return 1;
1672 return 0;
1676 /* Return nonzero if register in range [REGNO, ENDREGNO)
1677 appears either explicitly or implicitly in X
1678 other than being stored into.
1680 References contained within the substructure at LOC do not count.
1681 LOC may be zero, meaning don't ignore anything. */
1683 bool
1684 refers_to_regno_p (unsigned int regno, unsigned int endregno, const_rtx x,
1685 rtx *loc)
1687 int i;
1688 unsigned int x_regno;
1689 RTX_CODE code;
1690 const char *fmt;
1692 repeat:
1693 /* The contents of a REG_NONNEG note is always zero, so we must come here
1694 upon repeat in case the last REG_NOTE is a REG_NONNEG note. */
1695 if (x == 0)
1696 return false;
1698 code = GET_CODE (x);
1700 switch (code)
1702 case REG:
1703 x_regno = REGNO (x);
1705 /* If we modifying the stack, frame, or argument pointer, it will
1706 clobber a virtual register. In fact, we could be more precise,
1707 but it isn't worth it. */
1708 if ((x_regno == STACK_POINTER_REGNUM
1709 || (FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
1710 && x_regno == ARG_POINTER_REGNUM)
1711 || x_regno == FRAME_POINTER_REGNUM)
1712 && regno >= FIRST_VIRTUAL_REGISTER && regno <= LAST_VIRTUAL_REGISTER)
1713 return true;
1715 return endregno > x_regno && regno < END_REGNO (x);
1717 case SUBREG:
1718 /* If this is a SUBREG of a hard reg, we can see exactly which
1719 registers are being modified. Otherwise, handle normally. */
1720 if (REG_P (SUBREG_REG (x))
1721 && REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER)
1723 unsigned int inner_regno = subreg_regno (x);
1724 unsigned int inner_endregno
1725 = inner_regno + (inner_regno < FIRST_PSEUDO_REGISTER
1726 ? subreg_nregs (x) : 1);
1728 return endregno > inner_regno && regno < inner_endregno;
1730 break;
1732 case CLOBBER:
1733 case SET:
1734 if (&SET_DEST (x) != loc
1735 /* Note setting a SUBREG counts as referring to the REG it is in for
1736 a pseudo but not for hard registers since we can
1737 treat each word individually. */
1738 && ((GET_CODE (SET_DEST (x)) == SUBREG
1739 && loc != &SUBREG_REG (SET_DEST (x))
1740 && REG_P (SUBREG_REG (SET_DEST (x)))
1741 && REGNO (SUBREG_REG (SET_DEST (x))) >= FIRST_PSEUDO_REGISTER
1742 && refers_to_regno_p (regno, endregno,
1743 SUBREG_REG (SET_DEST (x)), loc))
1744 || (!REG_P (SET_DEST (x))
1745 && refers_to_regno_p (regno, endregno, SET_DEST (x), loc))))
1746 return true;
1748 if (code == CLOBBER || loc == &SET_SRC (x))
1749 return false;
1750 x = SET_SRC (x);
1751 goto repeat;
1753 default:
1754 break;
1757 /* X does not match, so try its subexpressions. */
1759 fmt = GET_RTX_FORMAT (code);
1760 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1762 if (fmt[i] == 'e' && loc != &XEXP (x, i))
1764 if (i == 0)
1766 x = XEXP (x, 0);
1767 goto repeat;
1769 else
1770 if (refers_to_regno_p (regno, endregno, XEXP (x, i), loc))
1771 return true;
1773 else if (fmt[i] == 'E')
1775 int j;
1776 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
1777 if (loc != &XVECEXP (x, i, j)
1778 && refers_to_regno_p (regno, endregno, XVECEXP (x, i, j), loc))
1779 return true;
1782 return false;
1785 /* Nonzero if modifying X will affect IN. If X is a register or a SUBREG,
1786 we check if any register number in X conflicts with the relevant register
1787 numbers. If X is a constant, return 0. If X is a MEM, return 1 iff IN
1788 contains a MEM (we don't bother checking for memory addresses that can't
1789 conflict because we expect this to be a rare case. */
1792 reg_overlap_mentioned_p (const_rtx x, const_rtx in)
1794 unsigned int regno, endregno;
1796 /* If either argument is a constant, then modifying X can not
1797 affect IN. Here we look at IN, we can profitably combine
1798 CONSTANT_P (x) with the switch statement below. */
1799 if (CONSTANT_P (in))
1800 return 0;
1802 recurse:
1803 switch (GET_CODE (x))
1805 case STRICT_LOW_PART:
1806 case ZERO_EXTRACT:
1807 case SIGN_EXTRACT:
1808 /* Overly conservative. */
1809 x = XEXP (x, 0);
1810 goto recurse;
1812 case SUBREG:
1813 regno = REGNO (SUBREG_REG (x));
1814 if (regno < FIRST_PSEUDO_REGISTER)
1815 regno = subreg_regno (x);
1816 endregno = regno + (regno < FIRST_PSEUDO_REGISTER
1817 ? subreg_nregs (x) : 1);
1818 goto do_reg;
1820 case REG:
1821 regno = REGNO (x);
1822 endregno = END_REGNO (x);
1823 do_reg:
1824 return refers_to_regno_p (regno, endregno, in, (rtx*) 0);
1826 case MEM:
1828 const char *fmt;
1829 int i;
1831 if (MEM_P (in))
1832 return 1;
1834 fmt = GET_RTX_FORMAT (GET_CODE (in));
1835 for (i = GET_RTX_LENGTH (GET_CODE (in)) - 1; i >= 0; i--)
1836 if (fmt[i] == 'e')
1838 if (reg_overlap_mentioned_p (x, XEXP (in, i)))
1839 return 1;
1841 else if (fmt[i] == 'E')
1843 int j;
1844 for (j = XVECLEN (in, i) - 1; j >= 0; --j)
1845 if (reg_overlap_mentioned_p (x, XVECEXP (in, i, j)))
1846 return 1;
1849 return 0;
1852 case SCRATCH:
1853 case PC:
1854 case CC0:
1855 return reg_mentioned_p (x, in);
1857 case PARALLEL:
1859 int i;
1861 /* If any register in here refers to it we return true. */
1862 for (i = XVECLEN (x, 0) - 1; i >= 0; i--)
1863 if (XEXP (XVECEXP (x, 0, i), 0) != 0
1864 && reg_overlap_mentioned_p (XEXP (XVECEXP (x, 0, i), 0), in))
1865 return 1;
1866 return 0;
1869 default:
1870 gcc_assert (CONSTANT_P (x));
1871 return 0;
1875 /* Call FUN on each register or MEM that is stored into or clobbered by X.
1876 (X would be the pattern of an insn). DATA is an arbitrary pointer,
1877 ignored by note_stores, but passed to FUN.
1879 FUN receives three arguments:
1880 1. the REG, MEM, CC0 or PC being stored in or clobbered,
1881 2. the SET or CLOBBER rtx that does the store,
1882 3. the pointer DATA provided to note_stores.
1884 If the item being stored in or clobbered is a SUBREG of a hard register,
1885 the SUBREG will be passed. */
1887 void
1888 note_stores (const_rtx x, void (*fun) (rtx, const_rtx, void *), void *data)
1890 int i;
1892 if (GET_CODE (x) == COND_EXEC)
1893 x = COND_EXEC_CODE (x);
1895 if (GET_CODE (x) == SET || GET_CODE (x) == CLOBBER)
1897 rtx dest = SET_DEST (x);
1899 while ((GET_CODE (dest) == SUBREG
1900 && (!REG_P (SUBREG_REG (dest))
1901 || REGNO (SUBREG_REG (dest)) >= FIRST_PSEUDO_REGISTER))
1902 || GET_CODE (dest) == ZERO_EXTRACT
1903 || GET_CODE (dest) == STRICT_LOW_PART)
1904 dest = XEXP (dest, 0);
1906 /* If we have a PARALLEL, SET_DEST is a list of EXPR_LIST expressions,
1907 each of whose first operand is a register. */
1908 if (GET_CODE (dest) == PARALLEL)
1910 for (i = XVECLEN (dest, 0) - 1; i >= 0; i--)
1911 if (XEXP (XVECEXP (dest, 0, i), 0) != 0)
1912 (*fun) (XEXP (XVECEXP (dest, 0, i), 0), x, data);
1914 else
1915 (*fun) (dest, x, data);
1918 else if (GET_CODE (x) == PARALLEL)
1919 for (i = XVECLEN (x, 0) - 1; i >= 0; i--)
1920 note_stores (XVECEXP (x, 0, i), fun, data);
1923 /* Like notes_stores, but call FUN for each expression that is being
1924 referenced in PBODY, a pointer to the PATTERN of an insn. We only call
1925 FUN for each expression, not any interior subexpressions. FUN receives a
1926 pointer to the expression and the DATA passed to this function.
1928 Note that this is not quite the same test as that done in reg_referenced_p
1929 since that considers something as being referenced if it is being
1930 partially set, while we do not. */
1932 void
1933 note_uses (rtx *pbody, void (*fun) (rtx *, void *), void *data)
1935 rtx body = *pbody;
1936 int i;
1938 switch (GET_CODE (body))
1940 case COND_EXEC:
1941 (*fun) (&COND_EXEC_TEST (body), data);
1942 note_uses (&COND_EXEC_CODE (body), fun, data);
1943 return;
1945 case PARALLEL:
1946 for (i = XVECLEN (body, 0) - 1; i >= 0; i--)
1947 note_uses (&XVECEXP (body, 0, i), fun, data);
1948 return;
1950 case SEQUENCE:
1951 for (i = XVECLEN (body, 0) - 1; i >= 0; i--)
1952 note_uses (&PATTERN (XVECEXP (body, 0, i)), fun, data);
1953 return;
1955 case USE:
1956 (*fun) (&XEXP (body, 0), data);
1957 return;
1959 case ASM_OPERANDS:
1960 for (i = ASM_OPERANDS_INPUT_LENGTH (body) - 1; i >= 0; i--)
1961 (*fun) (&ASM_OPERANDS_INPUT (body, i), data);
1962 return;
1964 case TRAP_IF:
1965 (*fun) (&TRAP_CONDITION (body), data);
1966 return;
1968 case PREFETCH:
1969 (*fun) (&XEXP (body, 0), data);
1970 return;
1972 case UNSPEC:
1973 case UNSPEC_VOLATILE:
1974 for (i = XVECLEN (body, 0) - 1; i >= 0; i--)
1975 (*fun) (&XVECEXP (body, 0, i), data);
1976 return;
1978 case CLOBBER:
1979 if (MEM_P (XEXP (body, 0)))
1980 (*fun) (&XEXP (XEXP (body, 0), 0), data);
1981 return;
1983 case SET:
1985 rtx dest = SET_DEST (body);
1987 /* For sets we replace everything in source plus registers in memory
1988 expression in store and operands of a ZERO_EXTRACT. */
1989 (*fun) (&SET_SRC (body), data);
1991 if (GET_CODE (dest) == ZERO_EXTRACT)
1993 (*fun) (&XEXP (dest, 1), data);
1994 (*fun) (&XEXP (dest, 2), data);
1997 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART)
1998 dest = XEXP (dest, 0);
2000 if (MEM_P (dest))
2001 (*fun) (&XEXP (dest, 0), data);
2003 return;
2005 default:
2006 /* All the other possibilities never store. */
2007 (*fun) (pbody, data);
2008 return;
2012 /* Return nonzero if X's old contents don't survive after INSN.
2013 This will be true if X is (cc0) or if X is a register and
2014 X dies in INSN or because INSN entirely sets X.
2016 "Entirely set" means set directly and not through a SUBREG, or
2017 ZERO_EXTRACT, so no trace of the old contents remains.
2018 Likewise, REG_INC does not count.
2020 REG may be a hard or pseudo reg. Renumbering is not taken into account,
2021 but for this use that makes no difference, since regs don't overlap
2022 during their lifetimes. Therefore, this function may be used
2023 at any time after deaths have been computed.
2025 If REG is a hard reg that occupies multiple machine registers, this
2026 function will only return 1 if each of those registers will be replaced
2027 by INSN. */
2030 dead_or_set_p (const rtx_insn *insn, const_rtx x)
2032 unsigned int regno, end_regno;
2033 unsigned int i;
2035 /* Can't use cc0_rtx below since this file is used by genattrtab.c. */
2036 if (GET_CODE (x) == CC0)
2037 return 1;
2039 gcc_assert (REG_P (x));
2041 regno = REGNO (x);
2042 end_regno = END_REGNO (x);
2043 for (i = regno; i < end_regno; i++)
2044 if (! dead_or_set_regno_p (insn, i))
2045 return 0;
2047 return 1;
2050 /* Return TRUE iff DEST is a register or subreg of a register, is a
2051 complete rather than read-modify-write destination, and contains
2052 register TEST_REGNO. */
2054 static bool
2055 covers_regno_no_parallel_p (const_rtx dest, unsigned int test_regno)
2057 unsigned int regno, endregno;
2059 if (GET_CODE (dest) == SUBREG && !read_modify_subreg_p (dest))
2060 dest = SUBREG_REG (dest);
2062 if (!REG_P (dest))
2063 return false;
2065 regno = REGNO (dest);
2066 endregno = END_REGNO (dest);
2067 return (test_regno >= regno && test_regno < endregno);
2070 /* Like covers_regno_no_parallel_p, but also handles PARALLELs where
2071 any member matches the covers_regno_no_parallel_p criteria. */
2073 static bool
2074 covers_regno_p (const_rtx dest, unsigned int test_regno)
2076 if (GET_CODE (dest) == PARALLEL)
2078 /* Some targets place small structures in registers for return
2079 values of functions, and those registers are wrapped in
2080 PARALLELs that we may see as the destination of a SET. */
2081 int i;
2083 for (i = XVECLEN (dest, 0) - 1; i >= 0; i--)
2085 rtx inner = XEXP (XVECEXP (dest, 0, i), 0);
2086 if (inner != NULL_RTX
2087 && covers_regno_no_parallel_p (inner, test_regno))
2088 return true;
2091 return false;
2093 else
2094 return covers_regno_no_parallel_p (dest, test_regno);
2097 /* Utility function for dead_or_set_p to check an individual register. */
2100 dead_or_set_regno_p (const rtx_insn *insn, unsigned int test_regno)
2102 const_rtx pattern;
2104 /* See if there is a death note for something that includes TEST_REGNO. */
2105 if (find_regno_note (insn, REG_DEAD, test_regno))
2106 return 1;
2108 if (CALL_P (insn)
2109 && find_regno_fusage (insn, CLOBBER, test_regno))
2110 return 1;
2112 pattern = PATTERN (insn);
2114 /* If a COND_EXEC is not executed, the value survives. */
2115 if (GET_CODE (pattern) == COND_EXEC)
2116 return 0;
2118 if (GET_CODE (pattern) == SET || GET_CODE (pattern) == CLOBBER)
2119 return covers_regno_p (SET_DEST (pattern), test_regno);
2120 else if (GET_CODE (pattern) == PARALLEL)
2122 int i;
2124 for (i = XVECLEN (pattern, 0) - 1; i >= 0; i--)
2126 rtx body = XVECEXP (pattern, 0, i);
2128 if (GET_CODE (body) == COND_EXEC)
2129 body = COND_EXEC_CODE (body);
2131 if ((GET_CODE (body) == SET || GET_CODE (body) == CLOBBER)
2132 && covers_regno_p (SET_DEST (body), test_regno))
2133 return 1;
2137 return 0;
2140 /* Return the reg-note of kind KIND in insn INSN, if there is one.
2141 If DATUM is nonzero, look for one whose datum is DATUM. */
2144 find_reg_note (const_rtx insn, enum reg_note kind, const_rtx datum)
2146 rtx link;
2148 gcc_checking_assert (insn);
2150 /* Ignore anything that is not an INSN, JUMP_INSN or CALL_INSN. */
2151 if (! INSN_P (insn))
2152 return 0;
2153 if (datum == 0)
2155 for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
2156 if (REG_NOTE_KIND (link) == kind)
2157 return link;
2158 return 0;
2161 for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
2162 if (REG_NOTE_KIND (link) == kind && datum == XEXP (link, 0))
2163 return link;
2164 return 0;
2167 /* Return the reg-note of kind KIND in insn INSN which applies to register
2168 number REGNO, if any. Return 0 if there is no such reg-note. Note that
2169 the REGNO of this NOTE need not be REGNO if REGNO is a hard register;
2170 it might be the case that the note overlaps REGNO. */
2173 find_regno_note (const_rtx insn, enum reg_note kind, unsigned int regno)
2175 rtx link;
2177 /* Ignore anything that is not an INSN, JUMP_INSN or CALL_INSN. */
2178 if (! INSN_P (insn))
2179 return 0;
2181 for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
2182 if (REG_NOTE_KIND (link) == kind
2183 /* Verify that it is a register, so that scratch and MEM won't cause a
2184 problem here. */
2185 && REG_P (XEXP (link, 0))
2186 && REGNO (XEXP (link, 0)) <= regno
2187 && END_REGNO (XEXP (link, 0)) > regno)
2188 return link;
2189 return 0;
2192 /* Return a REG_EQUIV or REG_EQUAL note if insn has only a single set and
2193 has such a note. */
2196 find_reg_equal_equiv_note (const_rtx insn)
2198 rtx link;
2200 if (!INSN_P (insn))
2201 return 0;
2203 for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
2204 if (REG_NOTE_KIND (link) == REG_EQUAL
2205 || REG_NOTE_KIND (link) == REG_EQUIV)
2207 /* FIXME: We should never have REG_EQUAL/REG_EQUIV notes on
2208 insns that have multiple sets. Checking single_set to
2209 make sure of this is not the proper check, as explained
2210 in the comment in set_unique_reg_note.
2212 This should be changed into an assert. */
2213 if (GET_CODE (PATTERN (insn)) == PARALLEL && multiple_sets (insn))
2214 return 0;
2215 return link;
2217 return NULL;
2220 /* Check whether INSN is a single_set whose source is known to be
2221 equivalent to a constant. Return that constant if so, otherwise
2222 return null. */
2225 find_constant_src (const rtx_insn *insn)
2227 rtx note, set, x;
2229 set = single_set (insn);
2230 if (set)
2232 x = avoid_constant_pool_reference (SET_SRC (set));
2233 if (CONSTANT_P (x))
2234 return x;
2237 note = find_reg_equal_equiv_note (insn);
2238 if (note && CONSTANT_P (XEXP (note, 0)))
2239 return XEXP (note, 0);
2241 return NULL_RTX;
2244 /* Return true if DATUM, or any overlap of DATUM, of kind CODE is found
2245 in the CALL_INSN_FUNCTION_USAGE information of INSN. */
2248 find_reg_fusage (const_rtx insn, enum rtx_code code, const_rtx datum)
2250 /* If it's not a CALL_INSN, it can't possibly have a
2251 CALL_INSN_FUNCTION_USAGE field, so don't bother checking. */
2252 if (!CALL_P (insn))
2253 return 0;
2255 gcc_assert (datum);
2257 if (!REG_P (datum))
2259 rtx link;
2261 for (link = CALL_INSN_FUNCTION_USAGE (insn);
2262 link;
2263 link = XEXP (link, 1))
2264 if (GET_CODE (XEXP (link, 0)) == code
2265 && rtx_equal_p (datum, XEXP (XEXP (link, 0), 0)))
2266 return 1;
2268 else
2270 unsigned int regno = REGNO (datum);
2272 /* CALL_INSN_FUNCTION_USAGE information cannot contain references
2273 to pseudo registers, so don't bother checking. */
2275 if (regno < FIRST_PSEUDO_REGISTER)
2277 unsigned int end_regno = END_REGNO (datum);
2278 unsigned int i;
2280 for (i = regno; i < end_regno; i++)
2281 if (find_regno_fusage (insn, code, i))
2282 return 1;
2286 return 0;
2289 /* Return true if REGNO, or any overlap of REGNO, of kind CODE is found
2290 in the CALL_INSN_FUNCTION_USAGE information of INSN. */
2293 find_regno_fusage (const_rtx insn, enum rtx_code code, unsigned int regno)
2295 rtx link;
2297 /* CALL_INSN_FUNCTION_USAGE information cannot contain references
2298 to pseudo registers, so don't bother checking. */
2300 if (regno >= FIRST_PSEUDO_REGISTER
2301 || !CALL_P (insn) )
2302 return 0;
2304 for (link = CALL_INSN_FUNCTION_USAGE (insn); link; link = XEXP (link, 1))
2306 rtx op, reg;
2308 if (GET_CODE (op = XEXP (link, 0)) == code
2309 && REG_P (reg = XEXP (op, 0))
2310 && REGNO (reg) <= regno
2311 && END_REGNO (reg) > regno)
2312 return 1;
2315 return 0;
2319 /* Return true if KIND is an integer REG_NOTE. */
2321 static bool
2322 int_reg_note_p (enum reg_note kind)
2324 return kind == REG_BR_PROB;
2327 /* Allocate a register note with kind KIND and datum DATUM. LIST is
2328 stored as the pointer to the next register note. */
2331 alloc_reg_note (enum reg_note kind, rtx datum, rtx list)
2333 rtx note;
2335 gcc_checking_assert (!int_reg_note_p (kind));
2336 switch (kind)
2338 case REG_CC_SETTER:
2339 case REG_CC_USER:
2340 case REG_LABEL_TARGET:
2341 case REG_LABEL_OPERAND:
2342 case REG_TM:
2343 /* These types of register notes use an INSN_LIST rather than an
2344 EXPR_LIST, so that copying is done right and dumps look
2345 better. */
2346 note = alloc_INSN_LIST (datum, list);
2347 PUT_REG_NOTE_KIND (note, kind);
2348 break;
2350 default:
2351 note = alloc_EXPR_LIST (kind, datum, list);
2352 break;
2355 return note;
2358 /* Add register note with kind KIND and datum DATUM to INSN. */
2360 void
2361 add_reg_note (rtx insn, enum reg_note kind, rtx datum)
2363 REG_NOTES (insn) = alloc_reg_note (kind, datum, REG_NOTES (insn));
2366 /* Add an integer register note with kind KIND and datum DATUM to INSN. */
2368 void
2369 add_int_reg_note (rtx_insn *insn, enum reg_note kind, int datum)
2371 gcc_checking_assert (int_reg_note_p (kind));
2372 REG_NOTES (insn) = gen_rtx_INT_LIST ((machine_mode) kind,
2373 datum, REG_NOTES (insn));
2376 /* Add a REG_ARGS_SIZE note to INSN with value VALUE. */
2378 void
2379 add_args_size_note (rtx_insn *insn, poly_int64 value)
2381 gcc_checking_assert (!find_reg_note (insn, REG_ARGS_SIZE, NULL_RTX));
2382 add_reg_note (insn, REG_ARGS_SIZE, gen_int_mode (value, Pmode));
2385 /* Add a register note like NOTE to INSN. */
2387 void
2388 add_shallow_copy_of_reg_note (rtx_insn *insn, rtx note)
2390 if (GET_CODE (note) == INT_LIST)
2391 add_int_reg_note (insn, REG_NOTE_KIND (note), XINT (note, 0));
2392 else
2393 add_reg_note (insn, REG_NOTE_KIND (note), XEXP (note, 0));
2396 /* Duplicate NOTE and return the copy. */
2398 duplicate_reg_note (rtx note)
2400 reg_note kind = REG_NOTE_KIND (note);
2402 if (GET_CODE (note) == INT_LIST)
2403 return gen_rtx_INT_LIST ((machine_mode) kind, XINT (note, 0), NULL_RTX);
2404 else if (GET_CODE (note) == EXPR_LIST)
2405 return alloc_reg_note (kind, copy_insn_1 (XEXP (note, 0)), NULL_RTX);
2406 else
2407 return alloc_reg_note (kind, XEXP (note, 0), NULL_RTX);
2410 /* Remove register note NOTE from the REG_NOTES of INSN. */
2412 void
2413 remove_note (rtx_insn *insn, const_rtx note)
2415 rtx link;
2417 if (note == NULL_RTX)
2418 return;
2420 if (REG_NOTES (insn) == note)
2421 REG_NOTES (insn) = XEXP (note, 1);
2422 else
2423 for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
2424 if (XEXP (link, 1) == note)
2426 XEXP (link, 1) = XEXP (note, 1);
2427 break;
2430 switch (REG_NOTE_KIND (note))
2432 case REG_EQUAL:
2433 case REG_EQUIV:
2434 df_notes_rescan (insn);
2435 break;
2436 default:
2437 break;
2441 /* Remove REG_EQUAL and/or REG_EQUIV notes if INSN has such notes.
2442 Return true if any note has been removed. */
2444 bool
2445 remove_reg_equal_equiv_notes (rtx_insn *insn)
2447 rtx *loc;
2448 bool ret = false;
2450 loc = &REG_NOTES (insn);
2451 while (*loc)
2453 enum reg_note kind = REG_NOTE_KIND (*loc);
2454 if (kind == REG_EQUAL || kind == REG_EQUIV)
2456 *loc = XEXP (*loc, 1);
2457 ret = true;
2459 else
2460 loc = &XEXP (*loc, 1);
2462 return ret;
2465 /* Remove all REG_EQUAL and REG_EQUIV notes referring to REGNO. */
2467 void
2468 remove_reg_equal_equiv_notes_for_regno (unsigned int regno)
2470 df_ref eq_use;
2472 if (!df)
2473 return;
2475 /* This loop is a little tricky. We cannot just go down the chain because
2476 it is being modified by some actions in the loop. So we just iterate
2477 over the head. We plan to drain the list anyway. */
2478 while ((eq_use = DF_REG_EQ_USE_CHAIN (regno)) != NULL)
2480 rtx_insn *insn = DF_REF_INSN (eq_use);
2481 rtx note = find_reg_equal_equiv_note (insn);
2483 /* This assert is generally triggered when someone deletes a REG_EQUAL
2484 or REG_EQUIV note by hacking the list manually rather than calling
2485 remove_note. */
2486 gcc_assert (note);
2488 remove_note (insn, note);
2492 /* Search LISTP (an EXPR_LIST) for an entry whose first operand is NODE and
2493 return 1 if it is found. A simple equality test is used to determine if
2494 NODE matches. */
2496 bool
2497 in_insn_list_p (const rtx_insn_list *listp, const rtx_insn *node)
2499 const_rtx x;
2501 for (x = listp; x; x = XEXP (x, 1))
2502 if (node == XEXP (x, 0))
2503 return true;
2505 return false;
2508 /* Search LISTP (an EXPR_LIST) for an entry whose first operand is NODE and
2509 remove that entry from the list if it is found.
2511 A simple equality test is used to determine if NODE matches. */
2513 void
2514 remove_node_from_expr_list (const_rtx node, rtx_expr_list **listp)
2516 rtx_expr_list *temp = *listp;
2517 rtx_expr_list *prev = NULL;
2519 while (temp)
2521 if (node == temp->element ())
2523 /* Splice the node out of the list. */
2524 if (prev)
2525 XEXP (prev, 1) = temp->next ();
2526 else
2527 *listp = temp->next ();
2529 return;
2532 prev = temp;
2533 temp = temp->next ();
2537 /* Search LISTP (an INSN_LIST) for an entry whose first operand is NODE and
2538 remove that entry from the list if it is found.
2540 A simple equality test is used to determine if NODE matches. */
2542 void
2543 remove_node_from_insn_list (const rtx_insn *node, rtx_insn_list **listp)
2545 rtx_insn_list *temp = *listp;
2546 rtx_insn_list *prev = NULL;
2548 while (temp)
2550 if (node == temp->insn ())
2552 /* Splice the node out of the list. */
2553 if (prev)
2554 XEXP (prev, 1) = temp->next ();
2555 else
2556 *listp = temp->next ();
2558 return;
2561 prev = temp;
2562 temp = temp->next ();
2566 /* Nonzero if X contains any volatile instructions. These are instructions
2567 which may cause unpredictable machine state instructions, and thus no
2568 instructions or register uses should be moved or combined across them.
2569 This includes only volatile asms and UNSPEC_VOLATILE instructions. */
2572 volatile_insn_p (const_rtx x)
2574 const RTX_CODE code = GET_CODE (x);
2575 switch (code)
2577 case LABEL_REF:
2578 case SYMBOL_REF:
2579 case CONST:
2580 CASE_CONST_ANY:
2581 case CC0:
2582 case PC:
2583 case REG:
2584 case SCRATCH:
2585 case CLOBBER:
2586 case ADDR_VEC:
2587 case ADDR_DIFF_VEC:
2588 case CALL:
2589 case MEM:
2590 return 0;
2592 case UNSPEC_VOLATILE:
2593 return 1;
2595 case ASM_INPUT:
2596 case ASM_OPERANDS:
2597 if (MEM_VOLATILE_P (x))
2598 return 1;
2600 default:
2601 break;
2604 /* Recursively scan the operands of this expression. */
2607 const char *const fmt = GET_RTX_FORMAT (code);
2608 int i;
2610 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2612 if (fmt[i] == 'e')
2614 if (volatile_insn_p (XEXP (x, i)))
2615 return 1;
2617 else if (fmt[i] == 'E')
2619 int j;
2620 for (j = 0; j < XVECLEN (x, i); j++)
2621 if (volatile_insn_p (XVECEXP (x, i, j)))
2622 return 1;
2626 return 0;
2629 /* Nonzero if X contains any volatile memory references
2630 UNSPEC_VOLATILE operations or volatile ASM_OPERANDS expressions. */
2633 volatile_refs_p (const_rtx x)
2635 const RTX_CODE code = GET_CODE (x);
2636 switch (code)
2638 case LABEL_REF:
2639 case SYMBOL_REF:
2640 case CONST:
2641 CASE_CONST_ANY:
2642 case CC0:
2643 case PC:
2644 case REG:
2645 case SCRATCH:
2646 case CLOBBER:
2647 case ADDR_VEC:
2648 case ADDR_DIFF_VEC:
2649 return 0;
2651 case UNSPEC_VOLATILE:
2652 return 1;
2654 case MEM:
2655 case ASM_INPUT:
2656 case ASM_OPERANDS:
2657 if (MEM_VOLATILE_P (x))
2658 return 1;
2660 default:
2661 break;
2664 /* Recursively scan the operands of this expression. */
2667 const char *const fmt = GET_RTX_FORMAT (code);
2668 int i;
2670 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2672 if (fmt[i] == 'e')
2674 if (volatile_refs_p (XEXP (x, i)))
2675 return 1;
2677 else if (fmt[i] == 'E')
2679 int j;
2680 for (j = 0; j < XVECLEN (x, i); j++)
2681 if (volatile_refs_p (XVECEXP (x, i, j)))
2682 return 1;
2686 return 0;
2689 /* Similar to above, except that it also rejects register pre- and post-
2690 incrementing. */
2693 side_effects_p (const_rtx x)
2695 const RTX_CODE code = GET_CODE (x);
2696 switch (code)
2698 case LABEL_REF:
2699 case SYMBOL_REF:
2700 case CONST:
2701 CASE_CONST_ANY:
2702 case CC0:
2703 case PC:
2704 case REG:
2705 case SCRATCH:
2706 case ADDR_VEC:
2707 case ADDR_DIFF_VEC:
2708 case VAR_LOCATION:
2709 return 0;
2711 case CLOBBER:
2712 /* Reject CLOBBER with a non-VOID mode. These are made by combine.c
2713 when some combination can't be done. If we see one, don't think
2714 that we can simplify the expression. */
2715 return (GET_MODE (x) != VOIDmode);
2717 case PRE_INC:
2718 case PRE_DEC:
2719 case POST_INC:
2720 case POST_DEC:
2721 case PRE_MODIFY:
2722 case POST_MODIFY:
2723 case CALL:
2724 case UNSPEC_VOLATILE:
2725 return 1;
2727 case MEM:
2728 case ASM_INPUT:
2729 case ASM_OPERANDS:
2730 if (MEM_VOLATILE_P (x))
2731 return 1;
2733 default:
2734 break;
2737 /* Recursively scan the operands of this expression. */
2740 const char *fmt = GET_RTX_FORMAT (code);
2741 int i;
2743 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2745 if (fmt[i] == 'e')
2747 if (side_effects_p (XEXP (x, i)))
2748 return 1;
2750 else if (fmt[i] == 'E')
2752 int j;
2753 for (j = 0; j < XVECLEN (x, i); j++)
2754 if (side_effects_p (XVECEXP (x, i, j)))
2755 return 1;
2759 return 0;
2762 /* Return nonzero if evaluating rtx X might cause a trap.
2763 FLAGS controls how to consider MEMs. A nonzero means the context
2764 of the access may have changed from the original, such that the
2765 address may have become invalid. */
2768 may_trap_p_1 (const_rtx x, unsigned flags)
2770 int i;
2771 enum rtx_code code;
2772 const char *fmt;
2774 /* We make no distinction currently, but this function is part of
2775 the internal target-hooks ABI so we keep the parameter as
2776 "unsigned flags". */
2777 bool code_changed = flags != 0;
2779 if (x == 0)
2780 return 0;
2781 code = GET_CODE (x);
2782 switch (code)
2784 /* Handle these cases quickly. */
2785 CASE_CONST_ANY:
2786 case SYMBOL_REF:
2787 case LABEL_REF:
2788 case CONST:
2789 case PC:
2790 case CC0:
2791 case REG:
2792 case SCRATCH:
2793 return 0;
2795 case UNSPEC:
2796 return targetm.unspec_may_trap_p (x, flags);
2798 case UNSPEC_VOLATILE:
2799 case ASM_INPUT:
2800 case TRAP_IF:
2801 return 1;
2803 case ASM_OPERANDS:
2804 return MEM_VOLATILE_P (x);
2806 /* Memory ref can trap unless it's a static var or a stack slot. */
2807 case MEM:
2808 /* Recognize specific pattern of stack checking probes. */
2809 if (flag_stack_check
2810 && MEM_VOLATILE_P (x)
2811 && XEXP (x, 0) == stack_pointer_rtx)
2812 return 1;
2813 if (/* MEM_NOTRAP_P only relates to the actual position of the memory
2814 reference; moving it out of context such as when moving code
2815 when optimizing, might cause its address to become invalid. */
2816 code_changed
2817 || !MEM_NOTRAP_P (x))
2819 poly_int64 size = MEM_SIZE_KNOWN_P (x) ? MEM_SIZE (x) : -1;
2820 return rtx_addr_can_trap_p_1 (XEXP (x, 0), 0, size,
2821 GET_MODE (x), code_changed);
2824 return 0;
2826 /* Division by a non-constant might trap. */
2827 case DIV:
2828 case MOD:
2829 case UDIV:
2830 case UMOD:
2831 if (HONOR_SNANS (x))
2832 return 1;
2833 if (SCALAR_FLOAT_MODE_P (GET_MODE (x)))
2834 return flag_trapping_math;
2835 if (!CONSTANT_P (XEXP (x, 1)) || (XEXP (x, 1) == const0_rtx))
2836 return 1;
2837 break;
2839 case EXPR_LIST:
2840 /* An EXPR_LIST is used to represent a function call. This
2841 certainly may trap. */
2842 return 1;
2844 case GE:
2845 case GT:
2846 case LE:
2847 case LT:
2848 case LTGT:
2849 case COMPARE:
2850 /* Some floating point comparisons may trap. */
2851 if (!flag_trapping_math)
2852 break;
2853 /* ??? There is no machine independent way to check for tests that trap
2854 when COMPARE is used, though many targets do make this distinction.
2855 For instance, sparc uses CCFPE for compares which generate exceptions
2856 and CCFP for compares which do not generate exceptions. */
2857 if (HONOR_NANS (x))
2858 return 1;
2859 /* But often the compare has some CC mode, so check operand
2860 modes as well. */
2861 if (HONOR_NANS (XEXP (x, 0))
2862 || HONOR_NANS (XEXP (x, 1)))
2863 return 1;
2864 break;
2866 case EQ:
2867 case NE:
2868 if (HONOR_SNANS (x))
2869 return 1;
2870 /* Often comparison is CC mode, so check operand modes. */
2871 if (HONOR_SNANS (XEXP (x, 0))
2872 || HONOR_SNANS (XEXP (x, 1)))
2873 return 1;
2874 break;
2876 case FIX:
2877 /* Conversion of floating point might trap. */
2878 if (flag_trapping_math && HONOR_NANS (XEXP (x, 0)))
2879 return 1;
2880 break;
2882 case NEG:
2883 case ABS:
2884 case SUBREG:
2885 /* These operations don't trap even with floating point. */
2886 break;
2888 default:
2889 /* Any floating arithmetic may trap. */
2890 if (SCALAR_FLOAT_MODE_P (GET_MODE (x)) && flag_trapping_math)
2891 return 1;
2894 fmt = GET_RTX_FORMAT (code);
2895 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2897 if (fmt[i] == 'e')
2899 if (may_trap_p_1 (XEXP (x, i), flags))
2900 return 1;
2902 else if (fmt[i] == 'E')
2904 int j;
2905 for (j = 0; j < XVECLEN (x, i); j++)
2906 if (may_trap_p_1 (XVECEXP (x, i, j), flags))
2907 return 1;
2910 return 0;
2913 /* Return nonzero if evaluating rtx X might cause a trap. */
2916 may_trap_p (const_rtx x)
2918 return may_trap_p_1 (x, 0);
2921 /* Same as above, but additionally return nonzero if evaluating rtx X might
2922 cause a fault. We define a fault for the purpose of this function as a
2923 erroneous execution condition that cannot be encountered during the normal
2924 execution of a valid program; the typical example is an unaligned memory
2925 access on a strict alignment machine. The compiler guarantees that it
2926 doesn't generate code that will fault from a valid program, but this
2927 guarantee doesn't mean anything for individual instructions. Consider
2928 the following example:
2930 struct S { int d; union { char *cp; int *ip; }; };
2932 int foo(struct S *s)
2934 if (s->d == 1)
2935 return *s->ip;
2936 else
2937 return *s->cp;
2940 on a strict alignment machine. In a valid program, foo will never be
2941 invoked on a structure for which d is equal to 1 and the underlying
2942 unique field of the union not aligned on a 4-byte boundary, but the
2943 expression *s->ip might cause a fault if considered individually.
2945 At the RTL level, potentially problematic expressions will almost always
2946 verify may_trap_p; for example, the above dereference can be emitted as
2947 (mem:SI (reg:P)) and this expression is may_trap_p for a generic register.
2948 However, suppose that foo is inlined in a caller that causes s->cp to
2949 point to a local character variable and guarantees that s->d is not set
2950 to 1; foo may have been effectively translated into pseudo-RTL as:
2952 if ((reg:SI) == 1)
2953 (set (reg:SI) (mem:SI (%fp - 7)))
2954 else
2955 (set (reg:QI) (mem:QI (%fp - 7)))
2957 Now (mem:SI (%fp - 7)) is considered as not may_trap_p since it is a
2958 memory reference to a stack slot, but it will certainly cause a fault
2959 on a strict alignment machine. */
2962 may_trap_or_fault_p (const_rtx x)
2964 return may_trap_p_1 (x, 1);
2967 /* Return nonzero if X contains a comparison that is not either EQ or NE,
2968 i.e., an inequality. */
2971 inequality_comparisons_p (const_rtx x)
2973 const char *fmt;
2974 int len, i;
2975 const enum rtx_code code = GET_CODE (x);
2977 switch (code)
2979 case REG:
2980 case SCRATCH:
2981 case PC:
2982 case CC0:
2983 CASE_CONST_ANY:
2984 case CONST:
2985 case LABEL_REF:
2986 case SYMBOL_REF:
2987 return 0;
2989 case LT:
2990 case LTU:
2991 case GT:
2992 case GTU:
2993 case LE:
2994 case LEU:
2995 case GE:
2996 case GEU:
2997 return 1;
2999 default:
3000 break;
3003 len = GET_RTX_LENGTH (code);
3004 fmt = GET_RTX_FORMAT (code);
3006 for (i = 0; i < len; i++)
3008 if (fmt[i] == 'e')
3010 if (inequality_comparisons_p (XEXP (x, i)))
3011 return 1;
3013 else if (fmt[i] == 'E')
3015 int j;
3016 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
3017 if (inequality_comparisons_p (XVECEXP (x, i, j)))
3018 return 1;
3022 return 0;
3025 /* Replace any occurrence of FROM in X with TO. The function does
3026 not enter into CONST_DOUBLE for the replace.
3028 Note that copying is not done so X must not be shared unless all copies
3029 are to be modified.
3031 ALL_REGS is true if we want to replace all REGs equal to FROM, not just
3032 those pointer-equal ones. */
3035 replace_rtx (rtx x, rtx from, rtx to, bool all_regs)
3037 int i, j;
3038 const char *fmt;
3040 if (x == from)
3041 return to;
3043 /* Allow this function to make replacements in EXPR_LISTs. */
3044 if (x == 0)
3045 return 0;
3047 if (all_regs
3048 && REG_P (x)
3049 && REG_P (from)
3050 && REGNO (x) == REGNO (from))
3052 gcc_assert (GET_MODE (x) == GET_MODE (from));
3053 return to;
3055 else if (GET_CODE (x) == SUBREG)
3057 rtx new_rtx = replace_rtx (SUBREG_REG (x), from, to, all_regs);
3059 if (CONST_INT_P (new_rtx))
3061 x = simplify_subreg (GET_MODE (x), new_rtx,
3062 GET_MODE (SUBREG_REG (x)),
3063 SUBREG_BYTE (x));
3064 gcc_assert (x);
3066 else
3067 SUBREG_REG (x) = new_rtx;
3069 return x;
3071 else if (GET_CODE (x) == ZERO_EXTEND)
3073 rtx new_rtx = replace_rtx (XEXP (x, 0), from, to, all_regs);
3075 if (CONST_INT_P (new_rtx))
3077 x = simplify_unary_operation (ZERO_EXTEND, GET_MODE (x),
3078 new_rtx, GET_MODE (XEXP (x, 0)));
3079 gcc_assert (x);
3081 else
3082 XEXP (x, 0) = new_rtx;
3084 return x;
3087 fmt = GET_RTX_FORMAT (GET_CODE (x));
3088 for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--)
3090 if (fmt[i] == 'e')
3091 XEXP (x, i) = replace_rtx (XEXP (x, i), from, to, all_regs);
3092 else if (fmt[i] == 'E')
3093 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
3094 XVECEXP (x, i, j) = replace_rtx (XVECEXP (x, i, j),
3095 from, to, all_regs);
3098 return x;
3101 /* Replace occurrences of the OLD_LABEL in *LOC with NEW_LABEL. Also track
3102 the change in LABEL_NUSES if UPDATE_LABEL_NUSES. */
3104 void
3105 replace_label (rtx *loc, rtx old_label, rtx new_label, bool update_label_nuses)
3107 /* Handle jump tables specially, since ADDR_{DIFF_,}VECs can be long. */
3108 rtx x = *loc;
3109 if (JUMP_TABLE_DATA_P (x))
3111 x = PATTERN (x);
3112 rtvec vec = XVEC (x, GET_CODE (x) == ADDR_DIFF_VEC);
3113 int len = GET_NUM_ELEM (vec);
3114 for (int i = 0; i < len; ++i)
3116 rtx ref = RTVEC_ELT (vec, i);
3117 if (XEXP (ref, 0) == old_label)
3119 XEXP (ref, 0) = new_label;
3120 if (update_label_nuses)
3122 ++LABEL_NUSES (new_label);
3123 --LABEL_NUSES (old_label);
3127 return;
3130 /* If this is a JUMP_INSN, then we also need to fix the JUMP_LABEL
3131 field. This is not handled by the iterator because it doesn't
3132 handle unprinted ('0') fields. */
3133 if (JUMP_P (x) && JUMP_LABEL (x) == old_label)
3134 JUMP_LABEL (x) = new_label;
3136 subrtx_ptr_iterator::array_type array;
3137 FOR_EACH_SUBRTX_PTR (iter, array, loc, ALL)
3139 rtx *loc = *iter;
3140 if (rtx x = *loc)
3142 if (GET_CODE (x) == SYMBOL_REF
3143 && CONSTANT_POOL_ADDRESS_P (x))
3145 rtx c = get_pool_constant (x);
3146 if (rtx_referenced_p (old_label, c))
3148 /* Create a copy of constant C; replace the label inside
3149 but do not update LABEL_NUSES because uses in constant pool
3150 are not counted. */
3151 rtx new_c = copy_rtx (c);
3152 replace_label (&new_c, old_label, new_label, false);
3154 /* Add the new constant NEW_C to constant pool and replace
3155 the old reference to constant by new reference. */
3156 rtx new_mem = force_const_mem (get_pool_mode (x), new_c);
3157 *loc = replace_rtx (x, x, XEXP (new_mem, 0));
3161 if ((GET_CODE (x) == LABEL_REF
3162 || GET_CODE (x) == INSN_LIST)
3163 && XEXP (x, 0) == old_label)
3165 XEXP (x, 0) = new_label;
3166 if (update_label_nuses)
3168 ++LABEL_NUSES (new_label);
3169 --LABEL_NUSES (old_label);
3176 void
3177 replace_label_in_insn (rtx_insn *insn, rtx_insn *old_label,
3178 rtx_insn *new_label, bool update_label_nuses)
3180 rtx insn_as_rtx = insn;
3181 replace_label (&insn_as_rtx, old_label, new_label, update_label_nuses);
3182 gcc_checking_assert (insn_as_rtx == insn);
3185 /* Return true if X is referenced in BODY. */
3187 bool
3188 rtx_referenced_p (const_rtx x, const_rtx body)
3190 subrtx_iterator::array_type array;
3191 FOR_EACH_SUBRTX (iter, array, body, ALL)
3192 if (const_rtx y = *iter)
3194 /* Check if a label_ref Y refers to label X. */
3195 if (GET_CODE (y) == LABEL_REF
3196 && LABEL_P (x)
3197 && label_ref_label (y) == x)
3198 return true;
3200 if (rtx_equal_p (x, y))
3201 return true;
3203 /* If Y is a reference to pool constant traverse the constant. */
3204 if (GET_CODE (y) == SYMBOL_REF
3205 && CONSTANT_POOL_ADDRESS_P (y))
3206 iter.substitute (get_pool_constant (y));
3208 return false;
3211 /* If INSN is a tablejump return true and store the label (before jump table) to
3212 *LABELP and the jump table to *TABLEP. LABELP and TABLEP may be NULL. */
3214 bool
3215 tablejump_p (const rtx_insn *insn, rtx_insn **labelp,
3216 rtx_jump_table_data **tablep)
3218 if (!JUMP_P (insn))
3219 return false;
3221 rtx target = JUMP_LABEL (insn);
3222 if (target == NULL_RTX || ANY_RETURN_P (target))
3223 return false;
3225 rtx_insn *label = as_a<rtx_insn *> (target);
3226 rtx_insn *table = next_insn (label);
3227 if (table == NULL_RTX || !JUMP_TABLE_DATA_P (table))
3228 return false;
3230 if (labelp)
3231 *labelp = label;
3232 if (tablep)
3233 *tablep = as_a <rtx_jump_table_data *> (table);
3234 return true;
3237 /* A subroutine of computed_jump_p, return 1 if X contains a REG or MEM or
3238 constant that is not in the constant pool and not in the condition
3239 of an IF_THEN_ELSE. */
3241 static int
3242 computed_jump_p_1 (const_rtx x)
3244 const enum rtx_code code = GET_CODE (x);
3245 int i, j;
3246 const char *fmt;
3248 switch (code)
3250 case LABEL_REF:
3251 case PC:
3252 return 0;
3254 case CONST:
3255 CASE_CONST_ANY:
3256 case SYMBOL_REF:
3257 case REG:
3258 return 1;
3260 case MEM:
3261 return ! (GET_CODE (XEXP (x, 0)) == SYMBOL_REF
3262 && CONSTANT_POOL_ADDRESS_P (XEXP (x, 0)));
3264 case IF_THEN_ELSE:
3265 return (computed_jump_p_1 (XEXP (x, 1))
3266 || computed_jump_p_1 (XEXP (x, 2)));
3268 default:
3269 break;
3272 fmt = GET_RTX_FORMAT (code);
3273 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
3275 if (fmt[i] == 'e'
3276 && computed_jump_p_1 (XEXP (x, i)))
3277 return 1;
3279 else if (fmt[i] == 'E')
3280 for (j = 0; j < XVECLEN (x, i); j++)
3281 if (computed_jump_p_1 (XVECEXP (x, i, j)))
3282 return 1;
3285 return 0;
3288 /* Return nonzero if INSN is an indirect jump (aka computed jump).
3290 Tablejumps and casesi insns are not considered indirect jumps;
3291 we can recognize them by a (use (label_ref)). */
3294 computed_jump_p (const rtx_insn *insn)
3296 int i;
3297 if (JUMP_P (insn))
3299 rtx pat = PATTERN (insn);
3301 /* If we have a JUMP_LABEL set, we're not a computed jump. */
3302 if (JUMP_LABEL (insn) != NULL)
3303 return 0;
3305 if (GET_CODE (pat) == PARALLEL)
3307 int len = XVECLEN (pat, 0);
3308 int has_use_labelref = 0;
3310 for (i = len - 1; i >= 0; i--)
3311 if (GET_CODE (XVECEXP (pat, 0, i)) == USE
3312 && (GET_CODE (XEXP (XVECEXP (pat, 0, i), 0))
3313 == LABEL_REF))
3315 has_use_labelref = 1;
3316 break;
3319 if (! has_use_labelref)
3320 for (i = len - 1; i >= 0; i--)
3321 if (GET_CODE (XVECEXP (pat, 0, i)) == SET
3322 && SET_DEST (XVECEXP (pat, 0, i)) == pc_rtx
3323 && computed_jump_p_1 (SET_SRC (XVECEXP (pat, 0, i))))
3324 return 1;
3326 else if (GET_CODE (pat) == SET
3327 && SET_DEST (pat) == pc_rtx
3328 && computed_jump_p_1 (SET_SRC (pat)))
3329 return 1;
3331 return 0;
3336 /* MEM has a PRE/POST-INC/DEC/MODIFY address X. Extract the operands of
3337 the equivalent add insn and pass the result to FN, using DATA as the
3338 final argument. */
3340 static int
3341 for_each_inc_dec_find_inc_dec (rtx mem, for_each_inc_dec_fn fn, void *data)
3343 rtx x = XEXP (mem, 0);
3344 switch (GET_CODE (x))
3346 case PRE_INC:
3347 case POST_INC:
3349 poly_int64 size = GET_MODE_SIZE (GET_MODE (mem));
3350 rtx r1 = XEXP (x, 0);
3351 rtx c = gen_int_mode (size, GET_MODE (r1));
3352 return fn (mem, x, r1, r1, c, data);
3355 case PRE_DEC:
3356 case POST_DEC:
3358 poly_int64 size = GET_MODE_SIZE (GET_MODE (mem));
3359 rtx r1 = XEXP (x, 0);
3360 rtx c = gen_int_mode (-size, GET_MODE (r1));
3361 return fn (mem, x, r1, r1, c, data);
3364 case PRE_MODIFY:
3365 case POST_MODIFY:
3367 rtx r1 = XEXP (x, 0);
3368 rtx add = XEXP (x, 1);
3369 return fn (mem, x, r1, add, NULL, data);
3372 default:
3373 gcc_unreachable ();
3377 /* Traverse *LOC looking for MEMs that have autoinc addresses.
3378 For each such autoinc operation found, call FN, passing it
3379 the innermost enclosing MEM, the operation itself, the RTX modified
3380 by the operation, two RTXs (the second may be NULL) that, once
3381 added, represent the value to be held by the modified RTX
3382 afterwards, and DATA. FN is to return 0 to continue the
3383 traversal or any other value to have it returned to the caller of
3384 for_each_inc_dec. */
3387 for_each_inc_dec (rtx x,
3388 for_each_inc_dec_fn fn,
3389 void *data)
3391 subrtx_var_iterator::array_type array;
3392 FOR_EACH_SUBRTX_VAR (iter, array, x, NONCONST)
3394 rtx mem = *iter;
3395 if (mem
3396 && MEM_P (mem)
3397 && GET_RTX_CLASS (GET_CODE (XEXP (mem, 0))) == RTX_AUTOINC)
3399 int res = for_each_inc_dec_find_inc_dec (mem, fn, data);
3400 if (res != 0)
3401 return res;
3402 iter.skip_subrtxes ();
3405 return 0;
3409 /* Searches X for any reference to REGNO, returning the rtx of the
3410 reference found if any. Otherwise, returns NULL_RTX. */
3413 regno_use_in (unsigned int regno, rtx x)
3415 const char *fmt;
3416 int i, j;
3417 rtx tem;
3419 if (REG_P (x) && REGNO (x) == regno)
3420 return x;
3422 fmt = GET_RTX_FORMAT (GET_CODE (x));
3423 for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--)
3425 if (fmt[i] == 'e')
3427 if ((tem = regno_use_in (regno, XEXP (x, i))))
3428 return tem;
3430 else if (fmt[i] == 'E')
3431 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
3432 if ((tem = regno_use_in (regno , XVECEXP (x, i, j))))
3433 return tem;
3436 return NULL_RTX;
3439 /* Return a value indicating whether OP, an operand of a commutative
3440 operation, is preferred as the first or second operand. The more
3441 positive the value, the stronger the preference for being the first
3442 operand. */
3445 commutative_operand_precedence (rtx op)
3447 enum rtx_code code = GET_CODE (op);
3449 /* Constants always become the second operand. Prefer "nice" constants. */
3450 if (code == CONST_INT)
3451 return -10;
3452 if (code == CONST_WIDE_INT)
3453 return -9;
3454 if (code == CONST_POLY_INT)
3455 return -8;
3456 if (code == CONST_DOUBLE)
3457 return -8;
3458 if (code == CONST_FIXED)
3459 return -8;
3460 op = avoid_constant_pool_reference (op);
3461 code = GET_CODE (op);
3463 switch (GET_RTX_CLASS (code))
3465 case RTX_CONST_OBJ:
3466 if (code == CONST_INT)
3467 return -7;
3468 if (code == CONST_WIDE_INT)
3469 return -6;
3470 if (code == CONST_POLY_INT)
3471 return -5;
3472 if (code == CONST_DOUBLE)
3473 return -5;
3474 if (code == CONST_FIXED)
3475 return -5;
3476 return -4;
3478 case RTX_EXTRA:
3479 /* SUBREGs of objects should come second. */
3480 if (code == SUBREG && OBJECT_P (SUBREG_REG (op)))
3481 return -3;
3482 return 0;
3484 case RTX_OBJ:
3485 /* Complex expressions should be the first, so decrease priority
3486 of objects. Prefer pointer objects over non pointer objects. */
3487 if ((REG_P (op) && REG_POINTER (op))
3488 || (MEM_P (op) && MEM_POINTER (op)))
3489 return -1;
3490 return -2;
3492 case RTX_COMM_ARITH:
3493 /* Prefer operands that are themselves commutative to be first.
3494 This helps to make things linear. In particular,
3495 (and (and (reg) (reg)) (not (reg))) is canonical. */
3496 return 4;
3498 case RTX_BIN_ARITH:
3499 /* If only one operand is a binary expression, it will be the first
3500 operand. In particular, (plus (minus (reg) (reg)) (neg (reg)))
3501 is canonical, although it will usually be further simplified. */
3502 return 2;
3504 case RTX_UNARY:
3505 /* Then prefer NEG and NOT. */
3506 if (code == NEG || code == NOT)
3507 return 1;
3508 /* FALLTHRU */
3510 default:
3511 return 0;
3515 /* Return 1 iff it is necessary to swap operands of commutative operation
3516 in order to canonicalize expression. */
3518 bool
3519 swap_commutative_operands_p (rtx x, rtx y)
3521 return (commutative_operand_precedence (x)
3522 < commutative_operand_precedence (y));
3525 /* Return 1 if X is an autoincrement side effect and the register is
3526 not the stack pointer. */
3528 auto_inc_p (const_rtx x)
3530 switch (GET_CODE (x))
3532 case PRE_INC:
3533 case POST_INC:
3534 case PRE_DEC:
3535 case POST_DEC:
3536 case PRE_MODIFY:
3537 case POST_MODIFY:
3538 /* There are no REG_INC notes for SP. */
3539 if (XEXP (x, 0) != stack_pointer_rtx)
3540 return 1;
3541 default:
3542 break;
3544 return 0;
3547 /* Return nonzero if IN contains a piece of rtl that has the address LOC. */
3549 loc_mentioned_in_p (rtx *loc, const_rtx in)
3551 enum rtx_code code;
3552 const char *fmt;
3553 int i, j;
3555 if (!in)
3556 return 0;
3558 code = GET_CODE (in);
3559 fmt = GET_RTX_FORMAT (code);
3560 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
3562 if (fmt[i] == 'e')
3564 if (loc == &XEXP (in, i) || loc_mentioned_in_p (loc, XEXP (in, i)))
3565 return 1;
3567 else if (fmt[i] == 'E')
3568 for (j = XVECLEN (in, i) - 1; j >= 0; j--)
3569 if (loc == &XVECEXP (in, i, j)
3570 || loc_mentioned_in_p (loc, XVECEXP (in, i, j)))
3571 return 1;
3573 return 0;
3576 /* Helper function for subreg_lsb. Given a subreg's OUTER_MODE, INNER_MODE,
3577 and SUBREG_BYTE, return the bit offset where the subreg begins
3578 (counting from the least significant bit of the operand). */
3580 poly_uint64
3581 subreg_lsb_1 (machine_mode outer_mode,
3582 machine_mode inner_mode,
3583 poly_uint64 subreg_byte)
3585 poly_uint64 subreg_end, trailing_bytes, byte_pos;
3587 /* A paradoxical subreg begins at bit position 0. */
3588 if (paradoxical_subreg_p (outer_mode, inner_mode))
3589 return 0;
3591 subreg_end = subreg_byte + GET_MODE_SIZE (outer_mode);
3592 trailing_bytes = GET_MODE_SIZE (inner_mode) - subreg_end;
3593 if (WORDS_BIG_ENDIAN && BYTES_BIG_ENDIAN)
3594 byte_pos = trailing_bytes;
3595 else if (!WORDS_BIG_ENDIAN && !BYTES_BIG_ENDIAN)
3596 byte_pos = subreg_byte;
3597 else
3599 /* When bytes and words have opposite endianness, we must be able
3600 to split offsets into words and bytes at compile time. */
3601 poly_uint64 leading_word_part
3602 = force_align_down (subreg_byte, UNITS_PER_WORD);
3603 poly_uint64 trailing_word_part
3604 = force_align_down (trailing_bytes, UNITS_PER_WORD);
3605 /* If the subreg crosses a word boundary ensure that
3606 it also begins and ends on a word boundary. */
3607 gcc_assert (known_le (subreg_end - leading_word_part,
3608 (unsigned int) UNITS_PER_WORD)
3609 || (known_eq (leading_word_part, subreg_byte)
3610 && known_eq (trailing_word_part, trailing_bytes)));
3611 if (WORDS_BIG_ENDIAN)
3612 byte_pos = trailing_word_part + (subreg_byte - leading_word_part);
3613 else
3614 byte_pos = leading_word_part + (trailing_bytes - trailing_word_part);
3617 return byte_pos * BITS_PER_UNIT;
3620 /* Given a subreg X, return the bit offset where the subreg begins
3621 (counting from the least significant bit of the reg). */
3623 poly_uint64
3624 subreg_lsb (const_rtx x)
3626 return subreg_lsb_1 (GET_MODE (x), GET_MODE (SUBREG_REG (x)),
3627 SUBREG_BYTE (x));
3630 /* Return the subreg byte offset for a subreg whose outer value has
3631 OUTER_BYTES bytes, whose inner value has INNER_BYTES bytes, and where
3632 there are LSB_SHIFT *bits* between the lsb of the outer value and the
3633 lsb of the inner value. This is the inverse of the calculation
3634 performed by subreg_lsb_1 (which converts byte offsets to bit shifts). */
3636 poly_uint64
3637 subreg_size_offset_from_lsb (poly_uint64 outer_bytes, poly_uint64 inner_bytes,
3638 poly_uint64 lsb_shift)
3640 /* A paradoxical subreg begins at bit position 0. */
3641 gcc_checking_assert (ordered_p (outer_bytes, inner_bytes));
3642 if (maybe_gt (outer_bytes, inner_bytes))
3644 gcc_checking_assert (known_eq (lsb_shift, 0U));
3645 return 0;
3648 poly_uint64 lower_bytes = exact_div (lsb_shift, BITS_PER_UNIT);
3649 poly_uint64 upper_bytes = inner_bytes - (lower_bytes + outer_bytes);
3650 if (WORDS_BIG_ENDIAN && BYTES_BIG_ENDIAN)
3651 return upper_bytes;
3652 else if (!WORDS_BIG_ENDIAN && !BYTES_BIG_ENDIAN)
3653 return lower_bytes;
3654 else
3656 /* When bytes and words have opposite endianness, we must be able
3657 to split offsets into words and bytes at compile time. */
3658 poly_uint64 lower_word_part = force_align_down (lower_bytes,
3659 UNITS_PER_WORD);
3660 poly_uint64 upper_word_part = force_align_down (upper_bytes,
3661 UNITS_PER_WORD);
3662 if (WORDS_BIG_ENDIAN)
3663 return upper_word_part + (lower_bytes - lower_word_part);
3664 else
3665 return lower_word_part + (upper_bytes - upper_word_part);
3669 /* Fill in information about a subreg of a hard register.
3670 xregno - A regno of an inner hard subreg_reg (or what will become one).
3671 xmode - The mode of xregno.
3672 offset - The byte offset.
3673 ymode - The mode of a top level SUBREG (or what may become one).
3674 info - Pointer to structure to fill in.
3676 Rather than considering one particular inner register (and thus one
3677 particular "outer" register) in isolation, this function really uses
3678 XREGNO as a model for a sequence of isomorphic hard registers. Thus the
3679 function does not check whether adding INFO->offset to XREGNO gives
3680 a valid hard register; even if INFO->offset + XREGNO is out of range,
3681 there might be another register of the same type that is in range.
3682 Likewise it doesn't check whether targetm.hard_regno_mode_ok accepts
3683 the new register, since that can depend on things like whether the final
3684 register number is even or odd. Callers that want to check whether
3685 this particular subreg can be replaced by a simple (reg ...) should
3686 use simplify_subreg_regno. */
3688 void
3689 subreg_get_info (unsigned int xregno, machine_mode xmode,
3690 poly_uint64 offset, machine_mode ymode,
3691 struct subreg_info *info)
3693 unsigned int nregs_xmode, nregs_ymode;
3695 gcc_assert (xregno < FIRST_PSEUDO_REGISTER);
3697 poly_uint64 xsize = GET_MODE_SIZE (xmode);
3698 poly_uint64 ysize = GET_MODE_SIZE (ymode);
3700 bool rknown = false;
3702 /* If the register representation of a non-scalar mode has holes in it,
3703 we expect the scalar units to be concatenated together, with the holes
3704 distributed evenly among the scalar units. Each scalar unit must occupy
3705 at least one register. */
3706 if (HARD_REGNO_NREGS_HAS_PADDING (xregno, xmode))
3708 /* As a consequence, we must be dealing with a constant number of
3709 scalars, and thus a constant offset and number of units. */
3710 HOST_WIDE_INT coffset = offset.to_constant ();
3711 HOST_WIDE_INT cysize = ysize.to_constant ();
3712 nregs_xmode = HARD_REGNO_NREGS_WITH_PADDING (xregno, xmode);
3713 unsigned int nunits = GET_MODE_NUNITS (xmode).to_constant ();
3714 scalar_mode xmode_unit = GET_MODE_INNER (xmode);
3715 gcc_assert (HARD_REGNO_NREGS_HAS_PADDING (xregno, xmode_unit));
3716 gcc_assert (nregs_xmode
3717 == (nunits
3718 * HARD_REGNO_NREGS_WITH_PADDING (xregno, xmode_unit)));
3719 gcc_assert (hard_regno_nregs (xregno, xmode)
3720 == hard_regno_nregs (xregno, xmode_unit) * nunits);
3722 /* You can only ask for a SUBREG of a value with holes in the middle
3723 if you don't cross the holes. (Such a SUBREG should be done by
3724 picking a different register class, or doing it in memory if
3725 necessary.) An example of a value with holes is XCmode on 32-bit
3726 x86 with -m128bit-long-double; it's represented in 6 32-bit registers,
3727 3 for each part, but in memory it's two 128-bit parts.
3728 Padding is assumed to be at the end (not necessarily the 'high part')
3729 of each unit. */
3730 if ((coffset / GET_MODE_SIZE (xmode_unit) + 1 < nunits)
3731 && (coffset / GET_MODE_SIZE (xmode_unit)
3732 != ((coffset + cysize - 1) / GET_MODE_SIZE (xmode_unit))))
3734 info->representable_p = false;
3735 rknown = true;
3738 else
3739 nregs_xmode = hard_regno_nregs (xregno, xmode);
3741 nregs_ymode = hard_regno_nregs (xregno, ymode);
3743 /* Subreg sizes must be ordered, so that we can tell whether they are
3744 partial, paradoxical or complete. */
3745 gcc_checking_assert (ordered_p (xsize, ysize));
3747 /* Paradoxical subregs are otherwise valid. */
3748 if (!rknown && known_eq (offset, 0U) && maybe_gt (ysize, xsize))
3750 info->representable_p = true;
3751 /* If this is a big endian paradoxical subreg, which uses more
3752 actual hard registers than the original register, we must
3753 return a negative offset so that we find the proper highpart
3754 of the register.
3756 We assume that the ordering of registers within a multi-register
3757 value has a consistent endianness: if bytes and register words
3758 have different endianness, the hard registers that make up a
3759 multi-register value must be at least word-sized. */
3760 if (REG_WORDS_BIG_ENDIAN)
3761 info->offset = (int) nregs_xmode - (int) nregs_ymode;
3762 else
3763 info->offset = 0;
3764 info->nregs = nregs_ymode;
3765 return;
3768 /* If registers store different numbers of bits in the different
3769 modes, we cannot generally form this subreg. */
3770 poly_uint64 regsize_xmode, regsize_ymode;
3771 if (!HARD_REGNO_NREGS_HAS_PADDING (xregno, xmode)
3772 && !HARD_REGNO_NREGS_HAS_PADDING (xregno, ymode)
3773 && multiple_p (xsize, nregs_xmode, &regsize_xmode)
3774 && multiple_p (ysize, nregs_ymode, &regsize_ymode))
3776 if (!rknown
3777 && ((nregs_ymode > 1 && maybe_gt (regsize_xmode, regsize_ymode))
3778 || (nregs_xmode > 1 && maybe_gt (regsize_ymode, regsize_xmode))))
3780 info->representable_p = false;
3781 if (!can_div_away_from_zero_p (ysize, regsize_xmode, &info->nregs)
3782 || !can_div_trunc_p (offset, regsize_xmode, &info->offset))
3783 /* Checked by validate_subreg. We must know at compile time
3784 which inner registers are being accessed. */
3785 gcc_unreachable ();
3786 return;
3788 /* It's not valid to extract a subreg of mode YMODE at OFFSET that
3789 would go outside of XMODE. */
3790 if (!rknown && maybe_gt (ysize + offset, xsize))
3792 info->representable_p = false;
3793 info->nregs = nregs_ymode;
3794 if (!can_div_trunc_p (offset, regsize_xmode, &info->offset))
3795 /* Checked by validate_subreg. We must know at compile time
3796 which inner registers are being accessed. */
3797 gcc_unreachable ();
3798 return;
3800 /* Quick exit for the simple and common case of extracting whole
3801 subregisters from a multiregister value. */
3802 /* ??? It would be better to integrate this into the code below,
3803 if we can generalize the concept enough and figure out how
3804 odd-sized modes can coexist with the other weird cases we support. */
3805 HOST_WIDE_INT count;
3806 if (!rknown
3807 && WORDS_BIG_ENDIAN == REG_WORDS_BIG_ENDIAN
3808 && known_eq (regsize_xmode, regsize_ymode)
3809 && constant_multiple_p (offset, regsize_ymode, &count))
3811 info->representable_p = true;
3812 info->nregs = nregs_ymode;
3813 info->offset = count;
3814 gcc_assert (info->offset + info->nregs <= (int) nregs_xmode);
3815 return;
3819 /* Lowpart subregs are otherwise valid. */
3820 if (!rknown && known_eq (offset, subreg_lowpart_offset (ymode, xmode)))
3822 info->representable_p = true;
3823 rknown = true;
3825 if (known_eq (offset, 0U) || nregs_xmode == nregs_ymode)
3827 info->offset = 0;
3828 info->nregs = nregs_ymode;
3829 return;
3833 /* Set NUM_BLOCKS to the number of independently-representable YMODE
3834 values there are in (reg:XMODE XREGNO). We can view the register
3835 as consisting of this number of independent "blocks", where each
3836 block occupies NREGS_YMODE registers and contains exactly one
3837 representable YMODE value. */
3838 gcc_assert ((nregs_xmode % nregs_ymode) == 0);
3839 unsigned int num_blocks = nregs_xmode / nregs_ymode;
3841 /* Calculate the number of bytes in each block. This must always
3842 be exact, otherwise we don't know how to verify the constraint.
3843 These conditions may be relaxed but subreg_regno_offset would
3844 need to be redesigned. */
3845 poly_uint64 bytes_per_block = exact_div (xsize, num_blocks);
3847 /* Get the number of the first block that contains the subreg and the byte
3848 offset of the subreg from the start of that block. */
3849 unsigned int block_number;
3850 poly_uint64 subblock_offset;
3851 if (!can_div_trunc_p (offset, bytes_per_block, &block_number,
3852 &subblock_offset))
3853 /* Checked by validate_subreg. We must know at compile time which
3854 inner registers are being accessed. */
3855 gcc_unreachable ();
3857 if (!rknown)
3859 /* Only the lowpart of each block is representable. */
3860 info->representable_p
3861 = known_eq (subblock_offset,
3862 subreg_size_lowpart_offset (ysize, bytes_per_block));
3863 rknown = true;
3866 /* We assume that the ordering of registers within a multi-register
3867 value has a consistent endianness: if bytes and register words
3868 have different endianness, the hard registers that make up a
3869 multi-register value must be at least word-sized. */
3870 if (WORDS_BIG_ENDIAN != REG_WORDS_BIG_ENDIAN)
3871 /* The block number we calculated above followed memory endianness.
3872 Convert it to register endianness by counting back from the end.
3873 (Note that, because of the assumption above, each block must be
3874 at least word-sized.) */
3875 info->offset = (num_blocks - block_number - 1) * nregs_ymode;
3876 else
3877 info->offset = block_number * nregs_ymode;
3878 info->nregs = nregs_ymode;
3881 /* This function returns the regno offset of a subreg expression.
3882 xregno - A regno of an inner hard subreg_reg (or what will become one).
3883 xmode - The mode of xregno.
3884 offset - The byte offset.
3885 ymode - The mode of a top level SUBREG (or what may become one).
3886 RETURN - The regno offset which would be used. */
3887 unsigned int
3888 subreg_regno_offset (unsigned int xregno, machine_mode xmode,
3889 poly_uint64 offset, machine_mode ymode)
3891 struct subreg_info info;
3892 subreg_get_info (xregno, xmode, offset, ymode, &info);
3893 return info.offset;
3896 /* This function returns true when the offset is representable via
3897 subreg_offset in the given regno.
3898 xregno - A regno of an inner hard subreg_reg (or what will become one).
3899 xmode - The mode of xregno.
3900 offset - The byte offset.
3901 ymode - The mode of a top level SUBREG (or what may become one).
3902 RETURN - Whether the offset is representable. */
3903 bool
3904 subreg_offset_representable_p (unsigned int xregno, machine_mode xmode,
3905 poly_uint64 offset, machine_mode ymode)
3907 struct subreg_info info;
3908 subreg_get_info (xregno, xmode, offset, ymode, &info);
3909 return info.representable_p;
3912 /* Return the number of a YMODE register to which
3914 (subreg:YMODE (reg:XMODE XREGNO) OFFSET)
3916 can be simplified. Return -1 if the subreg can't be simplified.
3918 XREGNO is a hard register number. */
3921 simplify_subreg_regno (unsigned int xregno, machine_mode xmode,
3922 poly_uint64 offset, machine_mode ymode)
3924 struct subreg_info info;
3925 unsigned int yregno;
3927 /* Give the backend a chance to disallow the mode change. */
3928 if (GET_MODE_CLASS (xmode) != MODE_COMPLEX_INT
3929 && GET_MODE_CLASS (xmode) != MODE_COMPLEX_FLOAT
3930 && !REG_CAN_CHANGE_MODE_P (xregno, xmode, ymode)
3931 /* We can use mode change in LRA for some transformations. */
3932 && ! lra_in_progress)
3933 return -1;
3935 /* We shouldn't simplify stack-related registers. */
3936 if ((!reload_completed || frame_pointer_needed)
3937 && xregno == FRAME_POINTER_REGNUM)
3938 return -1;
3940 if (FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3941 && xregno == ARG_POINTER_REGNUM)
3942 return -1;
3944 if (xregno == STACK_POINTER_REGNUM
3945 /* We should convert hard stack register in LRA if it is
3946 possible. */
3947 && ! lra_in_progress)
3948 return -1;
3950 /* Try to get the register offset. */
3951 subreg_get_info (xregno, xmode, offset, ymode, &info);
3952 if (!info.representable_p)
3953 return -1;
3955 /* Make sure that the offsetted register value is in range. */
3956 yregno = xregno + info.offset;
3957 if (!HARD_REGISTER_NUM_P (yregno))
3958 return -1;
3960 /* See whether (reg:YMODE YREGNO) is valid.
3962 ??? We allow invalid registers if (reg:XMODE XREGNO) is also invalid.
3963 This is a kludge to work around how complex FP arguments are passed
3964 on IA-64 and should be fixed. See PR target/49226. */
3965 if (!targetm.hard_regno_mode_ok (yregno, ymode)
3966 && targetm.hard_regno_mode_ok (xregno, xmode))
3967 return -1;
3969 return (int) yregno;
3972 /* Return the final regno that a subreg expression refers to. */
3973 unsigned int
3974 subreg_regno (const_rtx x)
3976 unsigned int ret;
3977 rtx subreg = SUBREG_REG (x);
3978 int regno = REGNO (subreg);
3980 ret = regno + subreg_regno_offset (regno,
3981 GET_MODE (subreg),
3982 SUBREG_BYTE (x),
3983 GET_MODE (x));
3984 return ret;
3988 /* Return the number of registers that a subreg expression refers
3989 to. */
3990 unsigned int
3991 subreg_nregs (const_rtx x)
3993 return subreg_nregs_with_regno (REGNO (SUBREG_REG (x)), x);
3996 /* Return the number of registers that a subreg REG with REGNO
3997 expression refers to. This is a copy of the rtlanal.c:subreg_nregs
3998 changed so that the regno can be passed in. */
4000 unsigned int
4001 subreg_nregs_with_regno (unsigned int regno, const_rtx x)
4003 struct subreg_info info;
4004 rtx subreg = SUBREG_REG (x);
4006 subreg_get_info (regno, GET_MODE (subreg), SUBREG_BYTE (x), GET_MODE (x),
4007 &info);
4008 return info.nregs;
4011 struct parms_set_data
4013 int nregs;
4014 HARD_REG_SET regs;
4017 /* Helper function for noticing stores to parameter registers. */
4018 static void
4019 parms_set (rtx x, const_rtx pat ATTRIBUTE_UNUSED, void *data)
4021 struct parms_set_data *const d = (struct parms_set_data *) data;
4022 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER
4023 && TEST_HARD_REG_BIT (d->regs, REGNO (x)))
4025 CLEAR_HARD_REG_BIT (d->regs, REGNO (x));
4026 d->nregs--;
4030 /* Look backward for first parameter to be loaded.
4031 Note that loads of all parameters will not necessarily be
4032 found if CSE has eliminated some of them (e.g., an argument
4033 to the outer function is passed down as a parameter).
4034 Do not skip BOUNDARY. */
4035 rtx_insn *
4036 find_first_parameter_load (rtx_insn *call_insn, rtx_insn *boundary)
4038 struct parms_set_data parm;
4039 rtx p;
4040 rtx_insn *before, *first_set;
4042 /* Since different machines initialize their parameter registers
4043 in different orders, assume nothing. Collect the set of all
4044 parameter registers. */
4045 CLEAR_HARD_REG_SET (parm.regs);
4046 parm.nregs = 0;
4047 for (p = CALL_INSN_FUNCTION_USAGE (call_insn); p; p = XEXP (p, 1))
4048 if (GET_CODE (XEXP (p, 0)) == USE
4049 && REG_P (XEXP (XEXP (p, 0), 0))
4050 && !STATIC_CHAIN_REG_P (XEXP (XEXP (p, 0), 0)))
4052 gcc_assert (REGNO (XEXP (XEXP (p, 0), 0)) < FIRST_PSEUDO_REGISTER);
4054 /* We only care about registers which can hold function
4055 arguments. */
4056 if (!FUNCTION_ARG_REGNO_P (REGNO (XEXP (XEXP (p, 0), 0))))
4057 continue;
4059 SET_HARD_REG_BIT (parm.regs, REGNO (XEXP (XEXP (p, 0), 0)));
4060 parm.nregs++;
4062 before = call_insn;
4063 first_set = call_insn;
4065 /* Search backward for the first set of a register in this set. */
4066 while (parm.nregs && before != boundary)
4068 before = PREV_INSN (before);
4070 /* It is possible that some loads got CSEed from one call to
4071 another. Stop in that case. */
4072 if (CALL_P (before))
4073 break;
4075 /* Our caller needs either ensure that we will find all sets
4076 (in case code has not been optimized yet), or take care
4077 for possible labels in a way by setting boundary to preceding
4078 CODE_LABEL. */
4079 if (LABEL_P (before))
4081 gcc_assert (before == boundary);
4082 break;
4085 if (INSN_P (before))
4087 int nregs_old = parm.nregs;
4088 note_stores (PATTERN (before), parms_set, &parm);
4089 /* If we found something that did not set a parameter reg,
4090 we're done. Do not keep going, as that might result
4091 in hoisting an insn before the setting of a pseudo
4092 that is used by the hoisted insn. */
4093 if (nregs_old != parm.nregs)
4094 first_set = before;
4095 else
4096 break;
4099 return first_set;
4102 /* Return true if we should avoid inserting code between INSN and preceding
4103 call instruction. */
4105 bool
4106 keep_with_call_p (const rtx_insn *insn)
4108 rtx set;
4110 if (INSN_P (insn) && (set = single_set (insn)) != NULL)
4112 if (REG_P (SET_DEST (set))
4113 && REGNO (SET_DEST (set)) < FIRST_PSEUDO_REGISTER
4114 && fixed_regs[REGNO (SET_DEST (set))]
4115 && general_operand (SET_SRC (set), VOIDmode))
4116 return true;
4117 if (REG_P (SET_SRC (set))
4118 && targetm.calls.function_value_regno_p (REGNO (SET_SRC (set)))
4119 && REG_P (SET_DEST (set))
4120 && REGNO (SET_DEST (set)) >= FIRST_PSEUDO_REGISTER)
4121 return true;
4122 /* There may be a stack pop just after the call and before the store
4123 of the return register. Search for the actual store when deciding
4124 if we can break or not. */
4125 if (SET_DEST (set) == stack_pointer_rtx)
4127 /* This CONST_CAST is okay because next_nonnote_insn just
4128 returns its argument and we assign it to a const_rtx
4129 variable. */
4130 const rtx_insn *i2
4131 = next_nonnote_insn (const_cast<rtx_insn *> (insn));
4132 if (i2 && keep_with_call_p (i2))
4133 return true;
4136 return false;
4139 /* Return true if LABEL is a target of JUMP_INSN. This applies only
4140 to non-complex jumps. That is, direct unconditional, conditional,
4141 and tablejumps, but not computed jumps or returns. It also does
4142 not apply to the fallthru case of a conditional jump. */
4144 bool
4145 label_is_jump_target_p (const_rtx label, const rtx_insn *jump_insn)
4147 rtx tmp = JUMP_LABEL (jump_insn);
4148 rtx_jump_table_data *table;
4150 if (label == tmp)
4151 return true;
4153 if (tablejump_p (jump_insn, NULL, &table))
4155 rtvec vec = table->get_labels ();
4156 int i, veclen = GET_NUM_ELEM (vec);
4158 for (i = 0; i < veclen; ++i)
4159 if (XEXP (RTVEC_ELT (vec, i), 0) == label)
4160 return true;
4163 if (find_reg_note (jump_insn, REG_LABEL_TARGET, label))
4164 return true;
4166 return false;
4170 /* Return an estimate of the cost of computing rtx X.
4171 One use is in cse, to decide which expression to keep in the hash table.
4172 Another is in rtl generation, to pick the cheapest way to multiply.
4173 Other uses like the latter are expected in the future.
4175 X appears as operand OPNO in an expression with code OUTER_CODE.
4176 SPEED specifies whether costs optimized for speed or size should
4177 be returned. */
4180 rtx_cost (rtx x, machine_mode mode, enum rtx_code outer_code,
4181 int opno, bool speed)
4183 int i, j;
4184 enum rtx_code code;
4185 const char *fmt;
4186 int total;
4187 int factor;
4189 if (x == 0)
4190 return 0;
4192 if (GET_MODE (x) != VOIDmode)
4193 mode = GET_MODE (x);
4195 /* A size N times larger than UNITS_PER_WORD likely needs N times as
4196 many insns, taking N times as long. */
4197 factor = estimated_poly_value (GET_MODE_SIZE (mode)) / UNITS_PER_WORD;
4198 if (factor == 0)
4199 factor = 1;
4201 /* Compute the default costs of certain things.
4202 Note that targetm.rtx_costs can override the defaults. */
4204 code = GET_CODE (x);
4205 switch (code)
4207 case MULT:
4208 /* Multiplication has time-complexity O(N*N), where N is the
4209 number of units (translated from digits) when using
4210 schoolbook long multiplication. */
4211 total = factor * factor * COSTS_N_INSNS (5);
4212 break;
4213 case DIV:
4214 case UDIV:
4215 case MOD:
4216 case UMOD:
4217 /* Similarly, complexity for schoolbook long division. */
4218 total = factor * factor * COSTS_N_INSNS (7);
4219 break;
4220 case USE:
4221 /* Used in combine.c as a marker. */
4222 total = 0;
4223 break;
4224 case SET:
4225 /* A SET doesn't have a mode, so let's look at the SET_DEST to get
4226 the mode for the factor. */
4227 mode = GET_MODE (SET_DEST (x));
4228 factor = estimated_poly_value (GET_MODE_SIZE (mode)) / UNITS_PER_WORD;
4229 if (factor == 0)
4230 factor = 1;
4231 /* FALLTHRU */
4232 default:
4233 total = factor * COSTS_N_INSNS (1);
4236 switch (code)
4238 case REG:
4239 return 0;
4241 case SUBREG:
4242 total = 0;
4243 /* If we can't tie these modes, make this expensive. The larger
4244 the mode, the more expensive it is. */
4245 if (!targetm.modes_tieable_p (mode, GET_MODE (SUBREG_REG (x))))
4246 return COSTS_N_INSNS (2 + factor);
4247 break;
4249 case TRUNCATE:
4250 if (targetm.modes_tieable_p (mode, GET_MODE (XEXP (x, 0))))
4252 total = 0;
4253 break;
4255 /* FALLTHRU */
4256 default:
4257 if (targetm.rtx_costs (x, mode, outer_code, opno, &total, speed))
4258 return total;
4259 break;
4262 /* Sum the costs of the sub-rtx's, plus cost of this operation,
4263 which is already in total. */
4265 fmt = GET_RTX_FORMAT (code);
4266 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
4267 if (fmt[i] == 'e')
4268 total += rtx_cost (XEXP (x, i), mode, code, i, speed);
4269 else if (fmt[i] == 'E')
4270 for (j = 0; j < XVECLEN (x, i); j++)
4271 total += rtx_cost (XVECEXP (x, i, j), mode, code, i, speed);
4273 return total;
4276 /* Fill in the structure C with information about both speed and size rtx
4277 costs for X, which is operand OPNO in an expression with code OUTER. */
4279 void
4280 get_full_rtx_cost (rtx x, machine_mode mode, enum rtx_code outer, int opno,
4281 struct full_rtx_costs *c)
4283 c->speed = rtx_cost (x, mode, outer, opno, true);
4284 c->size = rtx_cost (x, mode, outer, opno, false);
4288 /* Return cost of address expression X.
4289 Expect that X is properly formed address reference.
4291 SPEED parameter specify whether costs optimized for speed or size should
4292 be returned. */
4295 address_cost (rtx x, machine_mode mode, addr_space_t as, bool speed)
4297 /* We may be asked for cost of various unusual addresses, such as operands
4298 of push instruction. It is not worthwhile to complicate writing
4299 of the target hook by such cases. */
4301 if (!memory_address_addr_space_p (mode, x, as))
4302 return 1000;
4304 return targetm.address_cost (x, mode, as, speed);
4307 /* If the target doesn't override, compute the cost as with arithmetic. */
4310 default_address_cost (rtx x, machine_mode, addr_space_t, bool speed)
4312 return rtx_cost (x, Pmode, MEM, 0, speed);
4316 unsigned HOST_WIDE_INT
4317 nonzero_bits (const_rtx x, machine_mode mode)
4319 if (mode == VOIDmode)
4320 mode = GET_MODE (x);
4321 scalar_int_mode int_mode;
4322 if (!is_a <scalar_int_mode> (mode, &int_mode))
4323 return GET_MODE_MASK (mode);
4324 return cached_nonzero_bits (x, int_mode, NULL_RTX, VOIDmode, 0);
4327 unsigned int
4328 num_sign_bit_copies (const_rtx x, machine_mode mode)
4330 if (mode == VOIDmode)
4331 mode = GET_MODE (x);
4332 scalar_int_mode int_mode;
4333 if (!is_a <scalar_int_mode> (mode, &int_mode))
4334 return 1;
4335 return cached_num_sign_bit_copies (x, int_mode, NULL_RTX, VOIDmode, 0);
4338 /* Return true if nonzero_bits1 might recurse into both operands
4339 of X. */
4341 static inline bool
4342 nonzero_bits_binary_arith_p (const_rtx x)
4344 if (!ARITHMETIC_P (x))
4345 return false;
4346 switch (GET_CODE (x))
4348 case AND:
4349 case XOR:
4350 case IOR:
4351 case UMIN:
4352 case UMAX:
4353 case SMIN:
4354 case SMAX:
4355 case PLUS:
4356 case MINUS:
4357 case MULT:
4358 case DIV:
4359 case UDIV:
4360 case MOD:
4361 case UMOD:
4362 return true;
4363 default:
4364 return false;
4368 /* The function cached_nonzero_bits is a wrapper around nonzero_bits1.
4369 It avoids exponential behavior in nonzero_bits1 when X has
4370 identical subexpressions on the first or the second level. */
4372 static unsigned HOST_WIDE_INT
4373 cached_nonzero_bits (const_rtx x, scalar_int_mode mode, const_rtx known_x,
4374 machine_mode known_mode,
4375 unsigned HOST_WIDE_INT known_ret)
4377 if (x == known_x && mode == known_mode)
4378 return known_ret;
4380 /* Try to find identical subexpressions. If found call
4381 nonzero_bits1 on X with the subexpressions as KNOWN_X and the
4382 precomputed value for the subexpression as KNOWN_RET. */
4384 if (nonzero_bits_binary_arith_p (x))
4386 rtx x0 = XEXP (x, 0);
4387 rtx x1 = XEXP (x, 1);
4389 /* Check the first level. */
4390 if (x0 == x1)
4391 return nonzero_bits1 (x, mode, x0, mode,
4392 cached_nonzero_bits (x0, mode, known_x,
4393 known_mode, known_ret));
4395 /* Check the second level. */
4396 if (nonzero_bits_binary_arith_p (x0)
4397 && (x1 == XEXP (x0, 0) || x1 == XEXP (x0, 1)))
4398 return nonzero_bits1 (x, mode, x1, mode,
4399 cached_nonzero_bits (x1, mode, known_x,
4400 known_mode, known_ret));
4402 if (nonzero_bits_binary_arith_p (x1)
4403 && (x0 == XEXP (x1, 0) || x0 == XEXP (x1, 1)))
4404 return nonzero_bits1 (x, mode, x0, mode,
4405 cached_nonzero_bits (x0, mode, known_x,
4406 known_mode, known_ret));
4409 return nonzero_bits1 (x, mode, known_x, known_mode, known_ret);
4412 /* We let num_sign_bit_copies recur into nonzero_bits as that is useful.
4413 We don't let nonzero_bits recur into num_sign_bit_copies, because that
4414 is less useful. We can't allow both, because that results in exponential
4415 run time recursion. There is a nullstone testcase that triggered
4416 this. This macro avoids accidental uses of num_sign_bit_copies. */
4417 #define cached_num_sign_bit_copies sorry_i_am_preventing_exponential_behavior
4419 /* Given an expression, X, compute which bits in X can be nonzero.
4420 We don't care about bits outside of those defined in MODE.
4422 For most X this is simply GET_MODE_MASK (GET_MODE (X)), but if X is
4423 an arithmetic operation, we can do better. */
4425 static unsigned HOST_WIDE_INT
4426 nonzero_bits1 (const_rtx x, scalar_int_mode mode, const_rtx known_x,
4427 machine_mode known_mode,
4428 unsigned HOST_WIDE_INT known_ret)
4430 unsigned HOST_WIDE_INT nonzero = GET_MODE_MASK (mode);
4431 unsigned HOST_WIDE_INT inner_nz;
4432 enum rtx_code code;
4433 machine_mode inner_mode;
4434 unsigned int inner_width;
4435 scalar_int_mode xmode;
4437 unsigned int mode_width = GET_MODE_PRECISION (mode);
4439 if (CONST_INT_P (x))
4441 if (SHORT_IMMEDIATES_SIGN_EXTEND
4442 && INTVAL (x) > 0
4443 && mode_width < BITS_PER_WORD
4444 && (UINTVAL (x) & (HOST_WIDE_INT_1U << (mode_width - 1))) != 0)
4445 return UINTVAL (x) | (HOST_WIDE_INT_M1U << mode_width);
4447 return UINTVAL (x);
4450 if (!is_a <scalar_int_mode> (GET_MODE (x), &xmode))
4451 return nonzero;
4452 unsigned int xmode_width = GET_MODE_PRECISION (xmode);
4454 /* If X is wider than MODE, use its mode instead. */
4455 if (xmode_width > mode_width)
4457 mode = xmode;
4458 nonzero = GET_MODE_MASK (mode);
4459 mode_width = xmode_width;
4462 if (mode_width > HOST_BITS_PER_WIDE_INT)
4463 /* Our only callers in this case look for single bit values. So
4464 just return the mode mask. Those tests will then be false. */
4465 return nonzero;
4467 /* If MODE is wider than X, but both are a single word for both the host
4468 and target machines, we can compute this from which bits of the
4469 object might be nonzero in its own mode, taking into account the fact
4470 that on many CISC machines, accessing an object in a wider mode
4471 causes the high-order bits to become undefined. So they are
4472 not known to be zero. */
4474 if (!WORD_REGISTER_OPERATIONS
4475 && mode_width > xmode_width
4476 && xmode_width <= BITS_PER_WORD
4477 && xmode_width <= HOST_BITS_PER_WIDE_INT)
4479 nonzero &= cached_nonzero_bits (x, xmode,
4480 known_x, known_mode, known_ret);
4481 nonzero |= GET_MODE_MASK (mode) & ~GET_MODE_MASK (xmode);
4482 return nonzero;
4485 /* Please keep nonzero_bits_binary_arith_p above in sync with
4486 the code in the switch below. */
4487 code = GET_CODE (x);
4488 switch (code)
4490 case REG:
4491 #if defined(POINTERS_EXTEND_UNSIGNED)
4492 /* If pointers extend unsigned and this is a pointer in Pmode, say that
4493 all the bits above ptr_mode are known to be zero. */
4494 /* As we do not know which address space the pointer is referring to,
4495 we can do this only if the target does not support different pointer
4496 or address modes depending on the address space. */
4497 if (target_default_pointer_address_modes_p ()
4498 && POINTERS_EXTEND_UNSIGNED
4499 && xmode == Pmode
4500 && REG_POINTER (x)
4501 && !targetm.have_ptr_extend ())
4502 nonzero &= GET_MODE_MASK (ptr_mode);
4503 #endif
4505 /* Include declared information about alignment of pointers. */
4506 /* ??? We don't properly preserve REG_POINTER changes across
4507 pointer-to-integer casts, so we can't trust it except for
4508 things that we know must be pointers. See execute/960116-1.c. */
4509 if ((x == stack_pointer_rtx
4510 || x == frame_pointer_rtx
4511 || x == arg_pointer_rtx)
4512 && REGNO_POINTER_ALIGN (REGNO (x)))
4514 unsigned HOST_WIDE_INT alignment
4515 = REGNO_POINTER_ALIGN (REGNO (x)) / BITS_PER_UNIT;
4517 #ifdef PUSH_ROUNDING
4518 /* If PUSH_ROUNDING is defined, it is possible for the
4519 stack to be momentarily aligned only to that amount,
4520 so we pick the least alignment. */
4521 if (x == stack_pointer_rtx && PUSH_ARGS)
4523 poly_uint64 rounded_1 = PUSH_ROUNDING (poly_int64 (1));
4524 alignment = MIN (known_alignment (rounded_1), alignment);
4526 #endif
4528 nonzero &= ~(alignment - 1);
4532 unsigned HOST_WIDE_INT nonzero_for_hook = nonzero;
4533 rtx new_rtx = rtl_hooks.reg_nonzero_bits (x, xmode, mode,
4534 &nonzero_for_hook);
4536 if (new_rtx)
4537 nonzero_for_hook &= cached_nonzero_bits (new_rtx, mode, known_x,
4538 known_mode, known_ret);
4540 return nonzero_for_hook;
4543 case MEM:
4544 /* In many, if not most, RISC machines, reading a byte from memory
4545 zeros the rest of the register. Noticing that fact saves a lot
4546 of extra zero-extends. */
4547 if (load_extend_op (xmode) == ZERO_EXTEND)
4548 nonzero &= GET_MODE_MASK (xmode);
4549 break;
4551 case EQ: case NE:
4552 case UNEQ: case LTGT:
4553 case GT: case GTU: case UNGT:
4554 case LT: case LTU: case UNLT:
4555 case GE: case GEU: case UNGE:
4556 case LE: case LEU: case UNLE:
4557 case UNORDERED: case ORDERED:
4558 /* If this produces an integer result, we know which bits are set.
4559 Code here used to clear bits outside the mode of X, but that is
4560 now done above. */
4561 /* Mind that MODE is the mode the caller wants to look at this
4562 operation in, and not the actual operation mode. We can wind
4563 up with (subreg:DI (gt:V4HI x y)), and we don't have anything
4564 that describes the results of a vector compare. */
4565 if (GET_MODE_CLASS (xmode) == MODE_INT
4566 && mode_width <= HOST_BITS_PER_WIDE_INT)
4567 nonzero = STORE_FLAG_VALUE;
4568 break;
4570 case NEG:
4571 #if 0
4572 /* Disabled to avoid exponential mutual recursion between nonzero_bits
4573 and num_sign_bit_copies. */
4574 if (num_sign_bit_copies (XEXP (x, 0), xmode) == xmode_width)
4575 nonzero = 1;
4576 #endif
4578 if (xmode_width < mode_width)
4579 nonzero |= (GET_MODE_MASK (mode) & ~GET_MODE_MASK (xmode));
4580 break;
4582 case ABS:
4583 #if 0
4584 /* Disabled to avoid exponential mutual recursion between nonzero_bits
4585 and num_sign_bit_copies. */
4586 if (num_sign_bit_copies (XEXP (x, 0), xmode) == xmode_width)
4587 nonzero = 1;
4588 #endif
4589 break;
4591 case TRUNCATE:
4592 nonzero &= (cached_nonzero_bits (XEXP (x, 0), mode,
4593 known_x, known_mode, known_ret)
4594 & GET_MODE_MASK (mode));
4595 break;
4597 case ZERO_EXTEND:
4598 nonzero &= cached_nonzero_bits (XEXP (x, 0), mode,
4599 known_x, known_mode, known_ret);
4600 if (GET_MODE (XEXP (x, 0)) != VOIDmode)
4601 nonzero &= GET_MODE_MASK (GET_MODE (XEXP (x, 0)));
4602 break;
4604 case SIGN_EXTEND:
4605 /* If the sign bit is known clear, this is the same as ZERO_EXTEND.
4606 Otherwise, show all the bits in the outer mode but not the inner
4607 may be nonzero. */
4608 inner_nz = cached_nonzero_bits (XEXP (x, 0), mode,
4609 known_x, known_mode, known_ret);
4610 if (GET_MODE (XEXP (x, 0)) != VOIDmode)
4612 inner_nz &= GET_MODE_MASK (GET_MODE (XEXP (x, 0)));
4613 if (val_signbit_known_set_p (GET_MODE (XEXP (x, 0)), inner_nz))
4614 inner_nz |= (GET_MODE_MASK (mode)
4615 & ~GET_MODE_MASK (GET_MODE (XEXP (x, 0))));
4618 nonzero &= inner_nz;
4619 break;
4621 case AND:
4622 nonzero &= cached_nonzero_bits (XEXP (x, 0), mode,
4623 known_x, known_mode, known_ret)
4624 & cached_nonzero_bits (XEXP (x, 1), mode,
4625 known_x, known_mode, known_ret);
4626 break;
4628 case XOR: case IOR:
4629 case UMIN: case UMAX: case SMIN: case SMAX:
4631 unsigned HOST_WIDE_INT nonzero0
4632 = cached_nonzero_bits (XEXP (x, 0), mode,
4633 known_x, known_mode, known_ret);
4635 /* Don't call nonzero_bits for the second time if it cannot change
4636 anything. */
4637 if ((nonzero & nonzero0) != nonzero)
4638 nonzero &= nonzero0
4639 | cached_nonzero_bits (XEXP (x, 1), mode,
4640 known_x, known_mode, known_ret);
4642 break;
4644 case PLUS: case MINUS:
4645 case MULT:
4646 case DIV: case UDIV:
4647 case MOD: case UMOD:
4648 /* We can apply the rules of arithmetic to compute the number of
4649 high- and low-order zero bits of these operations. We start by
4650 computing the width (position of the highest-order nonzero bit)
4651 and the number of low-order zero bits for each value. */
4653 unsigned HOST_WIDE_INT nz0
4654 = cached_nonzero_bits (XEXP (x, 0), mode,
4655 known_x, known_mode, known_ret);
4656 unsigned HOST_WIDE_INT nz1
4657 = cached_nonzero_bits (XEXP (x, 1), mode,
4658 known_x, known_mode, known_ret);
4659 int sign_index = xmode_width - 1;
4660 int width0 = floor_log2 (nz0) + 1;
4661 int width1 = floor_log2 (nz1) + 1;
4662 int low0 = ctz_or_zero (nz0);
4663 int low1 = ctz_or_zero (nz1);
4664 unsigned HOST_WIDE_INT op0_maybe_minusp
4665 = nz0 & (HOST_WIDE_INT_1U << sign_index);
4666 unsigned HOST_WIDE_INT op1_maybe_minusp
4667 = nz1 & (HOST_WIDE_INT_1U << sign_index);
4668 unsigned int result_width = mode_width;
4669 int result_low = 0;
4671 switch (code)
4673 case PLUS:
4674 result_width = MAX (width0, width1) + 1;
4675 result_low = MIN (low0, low1);
4676 break;
4677 case MINUS:
4678 result_low = MIN (low0, low1);
4679 break;
4680 case MULT:
4681 result_width = width0 + width1;
4682 result_low = low0 + low1;
4683 break;
4684 case DIV:
4685 if (width1 == 0)
4686 break;
4687 if (!op0_maybe_minusp && !op1_maybe_minusp)
4688 result_width = width0;
4689 break;
4690 case UDIV:
4691 if (width1 == 0)
4692 break;
4693 result_width = width0;
4694 break;
4695 case MOD:
4696 if (width1 == 0)
4697 break;
4698 if (!op0_maybe_minusp && !op1_maybe_minusp)
4699 result_width = MIN (width0, width1);
4700 result_low = MIN (low0, low1);
4701 break;
4702 case UMOD:
4703 if (width1 == 0)
4704 break;
4705 result_width = MIN (width0, width1);
4706 result_low = MIN (low0, low1);
4707 break;
4708 default:
4709 gcc_unreachable ();
4712 if (result_width < mode_width)
4713 nonzero &= (HOST_WIDE_INT_1U << result_width) - 1;
4715 if (result_low > 0)
4716 nonzero &= ~((HOST_WIDE_INT_1U << result_low) - 1);
4718 break;
4720 case ZERO_EXTRACT:
4721 if (CONST_INT_P (XEXP (x, 1))
4722 && INTVAL (XEXP (x, 1)) < HOST_BITS_PER_WIDE_INT)
4723 nonzero &= (HOST_WIDE_INT_1U << INTVAL (XEXP (x, 1))) - 1;
4724 break;
4726 case SUBREG:
4727 /* If this is a SUBREG formed for a promoted variable that has
4728 been zero-extended, we know that at least the high-order bits
4729 are zero, though others might be too. */
4730 if (SUBREG_PROMOTED_VAR_P (x) && SUBREG_PROMOTED_UNSIGNED_P (x))
4731 nonzero = GET_MODE_MASK (xmode)
4732 & cached_nonzero_bits (SUBREG_REG (x), xmode,
4733 known_x, known_mode, known_ret);
4735 /* If the inner mode is a single word for both the host and target
4736 machines, we can compute this from which bits of the inner
4737 object might be nonzero. */
4738 inner_mode = GET_MODE (SUBREG_REG (x));
4739 if (GET_MODE_PRECISION (inner_mode).is_constant (&inner_width)
4740 && inner_width <= BITS_PER_WORD
4741 && inner_width <= HOST_BITS_PER_WIDE_INT)
4743 nonzero &= cached_nonzero_bits (SUBREG_REG (x), mode,
4744 known_x, known_mode, known_ret);
4746 /* On many CISC machines, accessing an object in a wider mode
4747 causes the high-order bits to become undefined. So they are
4748 not known to be zero. */
4749 rtx_code extend_op;
4750 if ((!WORD_REGISTER_OPERATIONS
4751 /* If this is a typical RISC machine, we only have to worry
4752 about the way loads are extended. */
4753 || ((extend_op = load_extend_op (inner_mode)) == SIGN_EXTEND
4754 ? val_signbit_known_set_p (inner_mode, nonzero)
4755 : extend_op != ZERO_EXTEND)
4756 || (!MEM_P (SUBREG_REG (x)) && !REG_P (SUBREG_REG (x))))
4757 && xmode_width > inner_width)
4758 nonzero
4759 |= (GET_MODE_MASK (GET_MODE (x)) & ~GET_MODE_MASK (inner_mode));
4761 break;
4763 case ASHIFTRT:
4764 case LSHIFTRT:
4765 case ASHIFT:
4766 case ROTATE:
4767 /* The nonzero bits are in two classes: any bits within MODE
4768 that aren't in xmode are always significant. The rest of the
4769 nonzero bits are those that are significant in the operand of
4770 the shift when shifted the appropriate number of bits. This
4771 shows that high-order bits are cleared by the right shift and
4772 low-order bits by left shifts. */
4773 if (CONST_INT_P (XEXP (x, 1))
4774 && INTVAL (XEXP (x, 1)) >= 0
4775 && INTVAL (XEXP (x, 1)) < HOST_BITS_PER_WIDE_INT
4776 && INTVAL (XEXP (x, 1)) < xmode_width)
4778 int count = INTVAL (XEXP (x, 1));
4779 unsigned HOST_WIDE_INT mode_mask = GET_MODE_MASK (xmode);
4780 unsigned HOST_WIDE_INT op_nonzero
4781 = cached_nonzero_bits (XEXP (x, 0), mode,
4782 known_x, known_mode, known_ret);
4783 unsigned HOST_WIDE_INT inner = op_nonzero & mode_mask;
4784 unsigned HOST_WIDE_INT outer = 0;
4786 if (mode_width > xmode_width)
4787 outer = (op_nonzero & nonzero & ~mode_mask);
4789 if (code == LSHIFTRT)
4790 inner >>= count;
4791 else if (code == ASHIFTRT)
4793 inner >>= count;
4795 /* If the sign bit may have been nonzero before the shift, we
4796 need to mark all the places it could have been copied to
4797 by the shift as possibly nonzero. */
4798 if (inner & (HOST_WIDE_INT_1U << (xmode_width - 1 - count)))
4799 inner |= (((HOST_WIDE_INT_1U << count) - 1)
4800 << (xmode_width - count));
4802 else if (code == ASHIFT)
4803 inner <<= count;
4804 else
4805 inner = ((inner << (count % xmode_width)
4806 | (inner >> (xmode_width - (count % xmode_width))))
4807 & mode_mask);
4809 nonzero &= (outer | inner);
4811 break;
4813 case FFS:
4814 case POPCOUNT:
4815 /* This is at most the number of bits in the mode. */
4816 nonzero = ((unsigned HOST_WIDE_INT) 2 << (floor_log2 (mode_width))) - 1;
4817 break;
4819 case CLZ:
4820 /* If CLZ has a known value at zero, then the nonzero bits are
4821 that value, plus the number of bits in the mode minus one. */
4822 if (CLZ_DEFINED_VALUE_AT_ZERO (mode, nonzero))
4823 nonzero
4824 |= (HOST_WIDE_INT_1U << (floor_log2 (mode_width))) - 1;
4825 else
4826 nonzero = -1;
4827 break;
4829 case CTZ:
4830 /* If CTZ has a known value at zero, then the nonzero bits are
4831 that value, plus the number of bits in the mode minus one. */
4832 if (CTZ_DEFINED_VALUE_AT_ZERO (mode, nonzero))
4833 nonzero
4834 |= (HOST_WIDE_INT_1U << (floor_log2 (mode_width))) - 1;
4835 else
4836 nonzero = -1;
4837 break;
4839 case CLRSB:
4840 /* This is at most the number of bits in the mode minus 1. */
4841 nonzero = (HOST_WIDE_INT_1U << (floor_log2 (mode_width))) - 1;
4842 break;
4844 case PARITY:
4845 nonzero = 1;
4846 break;
4848 case IF_THEN_ELSE:
4850 unsigned HOST_WIDE_INT nonzero_true
4851 = cached_nonzero_bits (XEXP (x, 1), mode,
4852 known_x, known_mode, known_ret);
4854 /* Don't call nonzero_bits for the second time if it cannot change
4855 anything. */
4856 if ((nonzero & nonzero_true) != nonzero)
4857 nonzero &= nonzero_true
4858 | cached_nonzero_bits (XEXP (x, 2), mode,
4859 known_x, known_mode, known_ret);
4861 break;
4863 default:
4864 break;
4867 return nonzero;
4870 /* See the macro definition above. */
4871 #undef cached_num_sign_bit_copies
4874 /* Return true if num_sign_bit_copies1 might recurse into both operands
4875 of X. */
4877 static inline bool
4878 num_sign_bit_copies_binary_arith_p (const_rtx x)
4880 if (!ARITHMETIC_P (x))
4881 return false;
4882 switch (GET_CODE (x))
4884 case IOR:
4885 case AND:
4886 case XOR:
4887 case SMIN:
4888 case SMAX:
4889 case UMIN:
4890 case UMAX:
4891 case PLUS:
4892 case MINUS:
4893 case MULT:
4894 return true;
4895 default:
4896 return false;
4900 /* The function cached_num_sign_bit_copies is a wrapper around
4901 num_sign_bit_copies1. It avoids exponential behavior in
4902 num_sign_bit_copies1 when X has identical subexpressions on the
4903 first or the second level. */
4905 static unsigned int
4906 cached_num_sign_bit_copies (const_rtx x, scalar_int_mode mode,
4907 const_rtx known_x, machine_mode known_mode,
4908 unsigned int known_ret)
4910 if (x == known_x && mode == known_mode)
4911 return known_ret;
4913 /* Try to find identical subexpressions. If found call
4914 num_sign_bit_copies1 on X with the subexpressions as KNOWN_X and
4915 the precomputed value for the subexpression as KNOWN_RET. */
4917 if (num_sign_bit_copies_binary_arith_p (x))
4919 rtx x0 = XEXP (x, 0);
4920 rtx x1 = XEXP (x, 1);
4922 /* Check the first level. */
4923 if (x0 == x1)
4924 return
4925 num_sign_bit_copies1 (x, mode, x0, mode,
4926 cached_num_sign_bit_copies (x0, mode, known_x,
4927 known_mode,
4928 known_ret));
4930 /* Check the second level. */
4931 if (num_sign_bit_copies_binary_arith_p (x0)
4932 && (x1 == XEXP (x0, 0) || x1 == XEXP (x0, 1)))
4933 return
4934 num_sign_bit_copies1 (x, mode, x1, mode,
4935 cached_num_sign_bit_copies (x1, mode, known_x,
4936 known_mode,
4937 known_ret));
4939 if (num_sign_bit_copies_binary_arith_p (x1)
4940 && (x0 == XEXP (x1, 0) || x0 == XEXP (x1, 1)))
4941 return
4942 num_sign_bit_copies1 (x, mode, x0, mode,
4943 cached_num_sign_bit_copies (x0, mode, known_x,
4944 known_mode,
4945 known_ret));
4948 return num_sign_bit_copies1 (x, mode, known_x, known_mode, known_ret);
4951 /* Return the number of bits at the high-order end of X that are known to
4952 be equal to the sign bit. X will be used in mode MODE. The returned
4953 value will always be between 1 and the number of bits in MODE. */
4955 static unsigned int
4956 num_sign_bit_copies1 (const_rtx x, scalar_int_mode mode, const_rtx known_x,
4957 machine_mode known_mode,
4958 unsigned int known_ret)
4960 enum rtx_code code = GET_CODE (x);
4961 unsigned int bitwidth = GET_MODE_PRECISION (mode);
4962 int num0, num1, result;
4963 unsigned HOST_WIDE_INT nonzero;
4965 if (CONST_INT_P (x))
4967 /* If the constant is negative, take its 1's complement and remask.
4968 Then see how many zero bits we have. */
4969 nonzero = UINTVAL (x) & GET_MODE_MASK (mode);
4970 if (bitwidth <= HOST_BITS_PER_WIDE_INT
4971 && (nonzero & (HOST_WIDE_INT_1U << (bitwidth - 1))) != 0)
4972 nonzero = (~nonzero) & GET_MODE_MASK (mode);
4974 return (nonzero == 0 ? bitwidth : bitwidth - floor_log2 (nonzero) - 1);
4977 scalar_int_mode xmode, inner_mode;
4978 if (!is_a <scalar_int_mode> (GET_MODE (x), &xmode))
4979 return 1;
4981 unsigned int xmode_width = GET_MODE_PRECISION (xmode);
4983 /* For a smaller mode, just ignore the high bits. */
4984 if (bitwidth < xmode_width)
4986 num0 = cached_num_sign_bit_copies (x, xmode,
4987 known_x, known_mode, known_ret);
4988 return MAX (1, num0 - (int) (xmode_width - bitwidth));
4991 if (bitwidth > xmode_width)
4993 /* If this machine does not do all register operations on the entire
4994 register and MODE is wider than the mode of X, we can say nothing
4995 at all about the high-order bits. */
4996 if (!WORD_REGISTER_OPERATIONS)
4997 return 1;
4999 /* Likewise on machines that do, if the mode of the object is smaller
5000 than a word and loads of that size don't sign extend, we can say
5001 nothing about the high order bits. */
5002 if (xmode_width < BITS_PER_WORD
5003 && load_extend_op (xmode) != SIGN_EXTEND)
5004 return 1;
5007 /* Please keep num_sign_bit_copies_binary_arith_p above in sync with
5008 the code in the switch below. */
5009 switch (code)
5011 case REG:
5013 #if defined(POINTERS_EXTEND_UNSIGNED)
5014 /* If pointers extend signed and this is a pointer in Pmode, say that
5015 all the bits above ptr_mode are known to be sign bit copies. */
5016 /* As we do not know which address space the pointer is referring to,
5017 we can do this only if the target does not support different pointer
5018 or address modes depending on the address space. */
5019 if (target_default_pointer_address_modes_p ()
5020 && ! POINTERS_EXTEND_UNSIGNED && xmode == Pmode
5021 && mode == Pmode && REG_POINTER (x)
5022 && !targetm.have_ptr_extend ())
5023 return GET_MODE_PRECISION (Pmode) - GET_MODE_PRECISION (ptr_mode) + 1;
5024 #endif
5027 unsigned int copies_for_hook = 1, copies = 1;
5028 rtx new_rtx = rtl_hooks.reg_num_sign_bit_copies (x, xmode, mode,
5029 &copies_for_hook);
5031 if (new_rtx)
5032 copies = cached_num_sign_bit_copies (new_rtx, mode, known_x,
5033 known_mode, known_ret);
5035 if (copies > 1 || copies_for_hook > 1)
5036 return MAX (copies, copies_for_hook);
5038 /* Else, use nonzero_bits to guess num_sign_bit_copies (see below). */
5040 break;
5042 case MEM:
5043 /* Some RISC machines sign-extend all loads of smaller than a word. */
5044 if (load_extend_op (xmode) == SIGN_EXTEND)
5045 return MAX (1, ((int) bitwidth - (int) xmode_width + 1));
5046 break;
5048 case SUBREG:
5049 /* If this is a SUBREG for a promoted object that is sign-extended
5050 and we are looking at it in a wider mode, we know that at least the
5051 high-order bits are known to be sign bit copies. */
5053 if (SUBREG_PROMOTED_VAR_P (x) && SUBREG_PROMOTED_SIGNED_P (x))
5055 num0 = cached_num_sign_bit_copies (SUBREG_REG (x), mode,
5056 known_x, known_mode, known_ret);
5057 return MAX ((int) bitwidth - (int) xmode_width + 1, num0);
5060 if (is_a <scalar_int_mode> (GET_MODE (SUBREG_REG (x)), &inner_mode))
5062 /* For a smaller object, just ignore the high bits. */
5063 if (bitwidth <= GET_MODE_PRECISION (inner_mode))
5065 num0 = cached_num_sign_bit_copies (SUBREG_REG (x), inner_mode,
5066 known_x, known_mode,
5067 known_ret);
5068 return MAX (1, num0 - (int) (GET_MODE_PRECISION (inner_mode)
5069 - bitwidth));
5072 /* For paradoxical SUBREGs on machines where all register operations
5073 affect the entire register, just look inside. Note that we are
5074 passing MODE to the recursive call, so the number of sign bit
5075 copies will remain relative to that mode, not the inner mode. */
5077 /* This works only if loads sign extend. Otherwise, if we get a
5078 reload for the inner part, it may be loaded from the stack, and
5079 then we lose all sign bit copies that existed before the store
5080 to the stack. */
5082 if (WORD_REGISTER_OPERATIONS
5083 && load_extend_op (inner_mode) == SIGN_EXTEND
5084 && paradoxical_subreg_p (x)
5085 && (MEM_P (SUBREG_REG (x)) || REG_P (SUBREG_REG (x))))
5086 return cached_num_sign_bit_copies (SUBREG_REG (x), mode,
5087 known_x, known_mode, known_ret);
5089 break;
5091 case SIGN_EXTRACT:
5092 if (CONST_INT_P (XEXP (x, 1)))
5093 return MAX (1, (int) bitwidth - INTVAL (XEXP (x, 1)));
5094 break;
5096 case SIGN_EXTEND:
5097 if (is_a <scalar_int_mode> (GET_MODE (XEXP (x, 0)), &inner_mode))
5098 return (bitwidth - GET_MODE_PRECISION (inner_mode)
5099 + cached_num_sign_bit_copies (XEXP (x, 0), inner_mode,
5100 known_x, known_mode, known_ret));
5101 break;
5103 case TRUNCATE:
5104 /* For a smaller object, just ignore the high bits. */
5105 inner_mode = as_a <scalar_int_mode> (GET_MODE (XEXP (x, 0)));
5106 num0 = cached_num_sign_bit_copies (XEXP (x, 0), inner_mode,
5107 known_x, known_mode, known_ret);
5108 return MAX (1, (num0 - (int) (GET_MODE_PRECISION (inner_mode)
5109 - bitwidth)));
5111 case NOT:
5112 return cached_num_sign_bit_copies (XEXP (x, 0), mode,
5113 known_x, known_mode, known_ret);
5115 case ROTATE: case ROTATERT:
5116 /* If we are rotating left by a number of bits less than the number
5117 of sign bit copies, we can just subtract that amount from the
5118 number. */
5119 if (CONST_INT_P (XEXP (x, 1))
5120 && INTVAL (XEXP (x, 1)) >= 0
5121 && INTVAL (XEXP (x, 1)) < (int) bitwidth)
5123 num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode,
5124 known_x, known_mode, known_ret);
5125 return MAX (1, num0 - (code == ROTATE ? INTVAL (XEXP (x, 1))
5126 : (int) bitwidth - INTVAL (XEXP (x, 1))));
5128 break;
5130 case NEG:
5131 /* In general, this subtracts one sign bit copy. But if the value
5132 is known to be positive, the number of sign bit copies is the
5133 same as that of the input. Finally, if the input has just one bit
5134 that might be nonzero, all the bits are copies of the sign bit. */
5135 num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode,
5136 known_x, known_mode, known_ret);
5137 if (bitwidth > HOST_BITS_PER_WIDE_INT)
5138 return num0 > 1 ? num0 - 1 : 1;
5140 nonzero = nonzero_bits (XEXP (x, 0), mode);
5141 if (nonzero == 1)
5142 return bitwidth;
5144 if (num0 > 1
5145 && ((HOST_WIDE_INT_1U << (bitwidth - 1)) & nonzero))
5146 num0--;
5148 return num0;
5150 case IOR: case AND: case XOR:
5151 case SMIN: case SMAX: case UMIN: case UMAX:
5152 /* Logical operations will preserve the number of sign-bit copies.
5153 MIN and MAX operations always return one of the operands. */
5154 num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode,
5155 known_x, known_mode, known_ret);
5156 num1 = cached_num_sign_bit_copies (XEXP (x, 1), mode,
5157 known_x, known_mode, known_ret);
5159 /* If num1 is clearing some of the top bits then regardless of
5160 the other term, we are guaranteed to have at least that many
5161 high-order zero bits. */
5162 if (code == AND
5163 && num1 > 1
5164 && bitwidth <= HOST_BITS_PER_WIDE_INT
5165 && CONST_INT_P (XEXP (x, 1))
5166 && (UINTVAL (XEXP (x, 1))
5167 & (HOST_WIDE_INT_1U << (bitwidth - 1))) == 0)
5168 return num1;
5170 /* Similarly for IOR when setting high-order bits. */
5171 if (code == IOR
5172 && num1 > 1
5173 && bitwidth <= HOST_BITS_PER_WIDE_INT
5174 && CONST_INT_P (XEXP (x, 1))
5175 && (UINTVAL (XEXP (x, 1))
5176 & (HOST_WIDE_INT_1U << (bitwidth - 1))) != 0)
5177 return num1;
5179 return MIN (num0, num1);
5181 case PLUS: case MINUS:
5182 /* For addition and subtraction, we can have a 1-bit carry. However,
5183 if we are subtracting 1 from a positive number, there will not
5184 be such a carry. Furthermore, if the positive number is known to
5185 be 0 or 1, we know the result is either -1 or 0. */
5187 if (code == PLUS && XEXP (x, 1) == constm1_rtx
5188 && bitwidth <= HOST_BITS_PER_WIDE_INT)
5190 nonzero = nonzero_bits (XEXP (x, 0), mode);
5191 if (((HOST_WIDE_INT_1U << (bitwidth - 1)) & nonzero) == 0)
5192 return (nonzero == 1 || nonzero == 0 ? bitwidth
5193 : bitwidth - floor_log2 (nonzero) - 1);
5196 num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode,
5197 known_x, known_mode, known_ret);
5198 num1 = cached_num_sign_bit_copies (XEXP (x, 1), mode,
5199 known_x, known_mode, known_ret);
5200 result = MAX (1, MIN (num0, num1) - 1);
5202 return result;
5204 case MULT:
5205 /* The number of bits of the product is the sum of the number of
5206 bits of both terms. However, unless one of the terms if known
5207 to be positive, we must allow for an additional bit since negating
5208 a negative number can remove one sign bit copy. */
5210 num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode,
5211 known_x, known_mode, known_ret);
5212 num1 = cached_num_sign_bit_copies (XEXP (x, 1), mode,
5213 known_x, known_mode, known_ret);
5215 result = bitwidth - (bitwidth - num0) - (bitwidth - num1);
5216 if (result > 0
5217 && (bitwidth > HOST_BITS_PER_WIDE_INT
5218 || (((nonzero_bits (XEXP (x, 0), mode)
5219 & (HOST_WIDE_INT_1U << (bitwidth - 1))) != 0)
5220 && ((nonzero_bits (XEXP (x, 1), mode)
5221 & (HOST_WIDE_INT_1U << (bitwidth - 1)))
5222 != 0))))
5223 result--;
5225 return MAX (1, result);
5227 case UDIV:
5228 /* The result must be <= the first operand. If the first operand
5229 has the high bit set, we know nothing about the number of sign
5230 bit copies. */
5231 if (bitwidth > HOST_BITS_PER_WIDE_INT)
5232 return 1;
5233 else if ((nonzero_bits (XEXP (x, 0), mode)
5234 & (HOST_WIDE_INT_1U << (bitwidth - 1))) != 0)
5235 return 1;
5236 else
5237 return cached_num_sign_bit_copies (XEXP (x, 0), mode,
5238 known_x, known_mode, known_ret);
5240 case UMOD:
5241 /* The result must be <= the second operand. If the second operand
5242 has (or just might have) the high bit set, we know nothing about
5243 the number of sign bit copies. */
5244 if (bitwidth > HOST_BITS_PER_WIDE_INT)
5245 return 1;
5246 else if ((nonzero_bits (XEXP (x, 1), mode)
5247 & (HOST_WIDE_INT_1U << (bitwidth - 1))) != 0)
5248 return 1;
5249 else
5250 return cached_num_sign_bit_copies (XEXP (x, 1), mode,
5251 known_x, known_mode, known_ret);
5253 case DIV:
5254 /* Similar to unsigned division, except that we have to worry about
5255 the case where the divisor is negative, in which case we have
5256 to add 1. */
5257 result = cached_num_sign_bit_copies (XEXP (x, 0), mode,
5258 known_x, known_mode, known_ret);
5259 if (result > 1
5260 && (bitwidth > HOST_BITS_PER_WIDE_INT
5261 || (nonzero_bits (XEXP (x, 1), mode)
5262 & (HOST_WIDE_INT_1U << (bitwidth - 1))) != 0))
5263 result--;
5265 return result;
5267 case MOD:
5268 result = cached_num_sign_bit_copies (XEXP (x, 1), mode,
5269 known_x, known_mode, known_ret);
5270 if (result > 1
5271 && (bitwidth > HOST_BITS_PER_WIDE_INT
5272 || (nonzero_bits (XEXP (x, 1), mode)
5273 & (HOST_WIDE_INT_1U << (bitwidth - 1))) != 0))
5274 result--;
5276 return result;
5278 case ASHIFTRT:
5279 /* Shifts by a constant add to the number of bits equal to the
5280 sign bit. */
5281 num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode,
5282 known_x, known_mode, known_ret);
5283 if (CONST_INT_P (XEXP (x, 1))
5284 && INTVAL (XEXP (x, 1)) > 0
5285 && INTVAL (XEXP (x, 1)) < xmode_width)
5286 num0 = MIN ((int) bitwidth, num0 + INTVAL (XEXP (x, 1)));
5288 return num0;
5290 case ASHIFT:
5291 /* Left shifts destroy copies. */
5292 if (!CONST_INT_P (XEXP (x, 1))
5293 || INTVAL (XEXP (x, 1)) < 0
5294 || INTVAL (XEXP (x, 1)) >= (int) bitwidth
5295 || INTVAL (XEXP (x, 1)) >= xmode_width)
5296 return 1;
5298 num0 = cached_num_sign_bit_copies (XEXP (x, 0), mode,
5299 known_x, known_mode, known_ret);
5300 return MAX (1, num0 - INTVAL (XEXP (x, 1)));
5302 case IF_THEN_ELSE:
5303 num0 = cached_num_sign_bit_copies (XEXP (x, 1), mode,
5304 known_x, known_mode, known_ret);
5305 num1 = cached_num_sign_bit_copies (XEXP (x, 2), mode,
5306 known_x, known_mode, known_ret);
5307 return MIN (num0, num1);
5309 case EQ: case NE: case GE: case GT: case LE: case LT:
5310 case UNEQ: case LTGT: case UNGE: case UNGT: case UNLE: case UNLT:
5311 case GEU: case GTU: case LEU: case LTU:
5312 case UNORDERED: case ORDERED:
5313 /* If the constant is negative, take its 1's complement and remask.
5314 Then see how many zero bits we have. */
5315 nonzero = STORE_FLAG_VALUE;
5316 if (bitwidth <= HOST_BITS_PER_WIDE_INT
5317 && (nonzero & (HOST_WIDE_INT_1U << (bitwidth - 1))) != 0)
5318 nonzero = (~nonzero) & GET_MODE_MASK (mode);
5320 return (nonzero == 0 ? bitwidth : bitwidth - floor_log2 (nonzero) - 1);
5322 default:
5323 break;
5326 /* If we haven't been able to figure it out by one of the above rules,
5327 see if some of the high-order bits are known to be zero. If so,
5328 count those bits and return one less than that amount. If we can't
5329 safely compute the mask for this mode, always return BITWIDTH. */
5331 bitwidth = GET_MODE_PRECISION (mode);
5332 if (bitwidth > HOST_BITS_PER_WIDE_INT)
5333 return 1;
5335 nonzero = nonzero_bits (x, mode);
5336 return nonzero & (HOST_WIDE_INT_1U << (bitwidth - 1))
5337 ? 1 : bitwidth - floor_log2 (nonzero) - 1;
5340 /* Calculate the rtx_cost of a single instruction pattern. A return value of
5341 zero indicates an instruction pattern without a known cost. */
5344 pattern_cost (rtx pat, bool speed)
5346 int i, cost;
5347 rtx set;
5349 /* Extract the single set rtx from the instruction pattern. We
5350 can't use single_set since we only have the pattern. We also
5351 consider PARALLELs of a normal set and a single comparison. In
5352 that case we use the cost of the non-comparison SET operation,
5353 which is most-likely to be the real cost of this operation. */
5354 if (GET_CODE (pat) == SET)
5355 set = pat;
5356 else if (GET_CODE (pat) == PARALLEL)
5358 set = NULL_RTX;
5359 rtx comparison = NULL_RTX;
5361 for (i = 0; i < XVECLEN (pat, 0); i++)
5363 rtx x = XVECEXP (pat, 0, i);
5364 if (GET_CODE (x) == SET)
5366 if (GET_CODE (SET_SRC (x)) == COMPARE)
5368 if (comparison)
5369 return 0;
5370 comparison = x;
5372 else
5374 if (set)
5375 return 0;
5376 set = x;
5381 if (!set && comparison)
5382 set = comparison;
5384 if (!set)
5385 return 0;
5387 else
5388 return 0;
5390 cost = set_src_cost (SET_SRC (set), GET_MODE (SET_DEST (set)), speed);
5391 return cost > 0 ? cost : COSTS_N_INSNS (1);
5394 /* Calculate the cost of a single instruction. A return value of zero
5395 indicates an instruction pattern without a known cost. */
5398 insn_cost (rtx_insn *insn, bool speed)
5400 if (targetm.insn_cost)
5401 return targetm.insn_cost (insn, speed);
5403 return pattern_cost (PATTERN (insn), speed);
5406 /* Returns estimate on cost of computing SEQ. */
5408 unsigned
5409 seq_cost (const rtx_insn *seq, bool speed)
5411 unsigned cost = 0;
5412 rtx set;
5414 for (; seq; seq = NEXT_INSN (seq))
5416 set = single_set (seq);
5417 if (set)
5418 cost += set_rtx_cost (set, speed);
5419 else if (NONDEBUG_INSN_P (seq))
5421 int this_cost = insn_cost (CONST_CAST_RTX_INSN (seq), speed);
5422 if (this_cost > 0)
5423 cost += this_cost;
5424 else
5425 cost++;
5429 return cost;
5432 /* Given an insn INSN and condition COND, return the condition in a
5433 canonical form to simplify testing by callers. Specifically:
5435 (1) The code will always be a comparison operation (EQ, NE, GT, etc.).
5436 (2) Both operands will be machine operands; (cc0) will have been replaced.
5437 (3) If an operand is a constant, it will be the second operand.
5438 (4) (LE x const) will be replaced with (LT x <const+1>) and similarly
5439 for GE, GEU, and LEU.
5441 If the condition cannot be understood, or is an inequality floating-point
5442 comparison which needs to be reversed, 0 will be returned.
5444 If REVERSE is nonzero, then reverse the condition prior to canonizing it.
5446 If EARLIEST is nonzero, it is a pointer to a place where the earliest
5447 insn used in locating the condition was found. If a replacement test
5448 of the condition is desired, it should be placed in front of that
5449 insn and we will be sure that the inputs are still valid.
5451 If WANT_REG is nonzero, we wish the condition to be relative to that
5452 register, if possible. Therefore, do not canonicalize the condition
5453 further. If ALLOW_CC_MODE is nonzero, allow the condition returned
5454 to be a compare to a CC mode register.
5456 If VALID_AT_INSN_P, the condition must be valid at both *EARLIEST
5457 and at INSN. */
5460 canonicalize_condition (rtx_insn *insn, rtx cond, int reverse,
5461 rtx_insn **earliest,
5462 rtx want_reg, int allow_cc_mode, int valid_at_insn_p)
5464 enum rtx_code code;
5465 rtx_insn *prev = insn;
5466 const_rtx set;
5467 rtx tem;
5468 rtx op0, op1;
5469 int reverse_code = 0;
5470 machine_mode mode;
5471 basic_block bb = BLOCK_FOR_INSN (insn);
5473 code = GET_CODE (cond);
5474 mode = GET_MODE (cond);
5475 op0 = XEXP (cond, 0);
5476 op1 = XEXP (cond, 1);
5478 if (reverse)
5479 code = reversed_comparison_code (cond, insn);
5480 if (code == UNKNOWN)
5481 return 0;
5483 if (earliest)
5484 *earliest = insn;
5486 /* If we are comparing a register with zero, see if the register is set
5487 in the previous insn to a COMPARE or a comparison operation. Perform
5488 the same tests as a function of STORE_FLAG_VALUE as find_comparison_args
5489 in cse.c */
5491 while ((GET_RTX_CLASS (code) == RTX_COMPARE
5492 || GET_RTX_CLASS (code) == RTX_COMM_COMPARE)
5493 && op1 == CONST0_RTX (GET_MODE (op0))
5494 && op0 != want_reg)
5496 /* Set nonzero when we find something of interest. */
5497 rtx x = 0;
5499 /* If comparison with cc0, import actual comparison from compare
5500 insn. */
5501 if (op0 == cc0_rtx)
5503 if ((prev = prev_nonnote_insn (prev)) == 0
5504 || !NONJUMP_INSN_P (prev)
5505 || (set = single_set (prev)) == 0
5506 || SET_DEST (set) != cc0_rtx)
5507 return 0;
5509 op0 = SET_SRC (set);
5510 op1 = CONST0_RTX (GET_MODE (op0));
5511 if (earliest)
5512 *earliest = prev;
5515 /* If this is a COMPARE, pick up the two things being compared. */
5516 if (GET_CODE (op0) == COMPARE)
5518 op1 = XEXP (op0, 1);
5519 op0 = XEXP (op0, 0);
5520 continue;
5522 else if (!REG_P (op0))
5523 break;
5525 /* Go back to the previous insn. Stop if it is not an INSN. We also
5526 stop if it isn't a single set or if it has a REG_INC note because
5527 we don't want to bother dealing with it. */
5529 prev = prev_nonnote_nondebug_insn (prev);
5531 if (prev == 0
5532 || !NONJUMP_INSN_P (prev)
5533 || FIND_REG_INC_NOTE (prev, NULL_RTX)
5534 /* In cfglayout mode, there do not have to be labels at the
5535 beginning of a block, or jumps at the end, so the previous
5536 conditions would not stop us when we reach bb boundary. */
5537 || BLOCK_FOR_INSN (prev) != bb)
5538 break;
5540 set = set_of (op0, prev);
5542 if (set
5543 && (GET_CODE (set) != SET
5544 || !rtx_equal_p (SET_DEST (set), op0)))
5545 break;
5547 /* If this is setting OP0, get what it sets it to if it looks
5548 relevant. */
5549 if (set)
5551 machine_mode inner_mode = GET_MODE (SET_DEST (set));
5552 #ifdef FLOAT_STORE_FLAG_VALUE
5553 REAL_VALUE_TYPE fsfv;
5554 #endif
5556 /* ??? We may not combine comparisons done in a CCmode with
5557 comparisons not done in a CCmode. This is to aid targets
5558 like Alpha that have an IEEE compliant EQ instruction, and
5559 a non-IEEE compliant BEQ instruction. The use of CCmode is
5560 actually artificial, simply to prevent the combination, but
5561 should not affect other platforms.
5563 However, we must allow VOIDmode comparisons to match either
5564 CCmode or non-CCmode comparison, because some ports have
5565 modeless comparisons inside branch patterns.
5567 ??? This mode check should perhaps look more like the mode check
5568 in simplify_comparison in combine. */
5569 if (((GET_MODE_CLASS (mode) == MODE_CC)
5570 != (GET_MODE_CLASS (inner_mode) == MODE_CC))
5571 && mode != VOIDmode
5572 && inner_mode != VOIDmode)
5573 break;
5574 if (GET_CODE (SET_SRC (set)) == COMPARE
5575 || (((code == NE
5576 || (code == LT
5577 && val_signbit_known_set_p (inner_mode,
5578 STORE_FLAG_VALUE))
5579 #ifdef FLOAT_STORE_FLAG_VALUE
5580 || (code == LT
5581 && SCALAR_FLOAT_MODE_P (inner_mode)
5582 && (fsfv = FLOAT_STORE_FLAG_VALUE (inner_mode),
5583 REAL_VALUE_NEGATIVE (fsfv)))
5584 #endif
5586 && COMPARISON_P (SET_SRC (set))))
5587 x = SET_SRC (set);
5588 else if (((code == EQ
5589 || (code == GE
5590 && val_signbit_known_set_p (inner_mode,
5591 STORE_FLAG_VALUE))
5592 #ifdef FLOAT_STORE_FLAG_VALUE
5593 || (code == GE
5594 && SCALAR_FLOAT_MODE_P (inner_mode)
5595 && (fsfv = FLOAT_STORE_FLAG_VALUE (inner_mode),
5596 REAL_VALUE_NEGATIVE (fsfv)))
5597 #endif
5599 && COMPARISON_P (SET_SRC (set)))
5601 reverse_code = 1;
5602 x = SET_SRC (set);
5604 else if ((code == EQ || code == NE)
5605 && GET_CODE (SET_SRC (set)) == XOR)
5606 /* Handle sequences like:
5608 (set op0 (xor X Y))
5609 ...(eq|ne op0 (const_int 0))...
5611 in which case:
5613 (eq op0 (const_int 0)) reduces to (eq X Y)
5614 (ne op0 (const_int 0)) reduces to (ne X Y)
5616 This is the form used by MIPS16, for example. */
5617 x = SET_SRC (set);
5618 else
5619 break;
5622 else if (reg_set_p (op0, prev))
5623 /* If this sets OP0, but not directly, we have to give up. */
5624 break;
5626 if (x)
5628 /* If the caller is expecting the condition to be valid at INSN,
5629 make sure X doesn't change before INSN. */
5630 if (valid_at_insn_p)
5631 if (modified_in_p (x, prev) || modified_between_p (x, prev, insn))
5632 break;
5633 if (COMPARISON_P (x))
5634 code = GET_CODE (x);
5635 if (reverse_code)
5637 code = reversed_comparison_code (x, prev);
5638 if (code == UNKNOWN)
5639 return 0;
5640 reverse_code = 0;
5643 op0 = XEXP (x, 0), op1 = XEXP (x, 1);
5644 if (earliest)
5645 *earliest = prev;
5649 /* If constant is first, put it last. */
5650 if (CONSTANT_P (op0))
5651 code = swap_condition (code), tem = op0, op0 = op1, op1 = tem;
5653 /* If OP0 is the result of a comparison, we weren't able to find what
5654 was really being compared, so fail. */
5655 if (!allow_cc_mode
5656 && GET_MODE_CLASS (GET_MODE (op0)) == MODE_CC)
5657 return 0;
5659 /* Canonicalize any ordered comparison with integers involving equality
5660 if we can do computations in the relevant mode and we do not
5661 overflow. */
5663 scalar_int_mode op0_mode;
5664 if (CONST_INT_P (op1)
5665 && is_a <scalar_int_mode> (GET_MODE (op0), &op0_mode)
5666 && GET_MODE_PRECISION (op0_mode) <= HOST_BITS_PER_WIDE_INT)
5668 HOST_WIDE_INT const_val = INTVAL (op1);
5669 unsigned HOST_WIDE_INT uconst_val = const_val;
5670 unsigned HOST_WIDE_INT max_val
5671 = (unsigned HOST_WIDE_INT) GET_MODE_MASK (op0_mode);
5673 switch (code)
5675 case LE:
5676 if ((unsigned HOST_WIDE_INT) const_val != max_val >> 1)
5677 code = LT, op1 = gen_int_mode (const_val + 1, op0_mode);
5678 break;
5680 /* When cross-compiling, const_val might be sign-extended from
5681 BITS_PER_WORD to HOST_BITS_PER_WIDE_INT */
5682 case GE:
5683 if ((const_val & max_val)
5684 != (HOST_WIDE_INT_1U << (GET_MODE_PRECISION (op0_mode) - 1)))
5685 code = GT, op1 = gen_int_mode (const_val - 1, op0_mode);
5686 break;
5688 case LEU:
5689 if (uconst_val < max_val)
5690 code = LTU, op1 = gen_int_mode (uconst_val + 1, op0_mode);
5691 break;
5693 case GEU:
5694 if (uconst_val != 0)
5695 code = GTU, op1 = gen_int_mode (uconst_val - 1, op0_mode);
5696 break;
5698 default:
5699 break;
5703 /* Never return CC0; return zero instead. */
5704 if (CC0_P (op0))
5705 return 0;
5707 /* We promised to return a comparison. */
5708 rtx ret = gen_rtx_fmt_ee (code, VOIDmode, op0, op1);
5709 if (COMPARISON_P (ret))
5710 return ret;
5711 return 0;
5714 /* Given a jump insn JUMP, return the condition that will cause it to branch
5715 to its JUMP_LABEL. If the condition cannot be understood, or is an
5716 inequality floating-point comparison which needs to be reversed, 0 will
5717 be returned.
5719 If EARLIEST is nonzero, it is a pointer to a place where the earliest
5720 insn used in locating the condition was found. If a replacement test
5721 of the condition is desired, it should be placed in front of that
5722 insn and we will be sure that the inputs are still valid. If EARLIEST
5723 is null, the returned condition will be valid at INSN.
5725 If ALLOW_CC_MODE is nonzero, allow the condition returned to be a
5726 compare CC mode register.
5728 VALID_AT_INSN_P is the same as for canonicalize_condition. */
5731 get_condition (rtx_insn *jump, rtx_insn **earliest, int allow_cc_mode,
5732 int valid_at_insn_p)
5734 rtx cond;
5735 int reverse;
5736 rtx set;
5738 /* If this is not a standard conditional jump, we can't parse it. */
5739 if (!JUMP_P (jump)
5740 || ! any_condjump_p (jump))
5741 return 0;
5742 set = pc_set (jump);
5744 cond = XEXP (SET_SRC (set), 0);
5746 /* If this branches to JUMP_LABEL when the condition is false, reverse
5747 the condition. */
5748 reverse
5749 = GET_CODE (XEXP (SET_SRC (set), 2)) == LABEL_REF
5750 && label_ref_label (XEXP (SET_SRC (set), 2)) == JUMP_LABEL (jump);
5752 return canonicalize_condition (jump, cond, reverse, earliest, NULL_RTX,
5753 allow_cc_mode, valid_at_insn_p);
5756 /* Initialize the table NUM_SIGN_BIT_COPIES_IN_REP based on
5757 TARGET_MODE_REP_EXTENDED.
5759 Note that we assume that the property of
5760 TARGET_MODE_REP_EXTENDED(B, C) is sticky to the integral modes
5761 narrower than mode B. I.e., if A is a mode narrower than B then in
5762 order to be able to operate on it in mode B, mode A needs to
5763 satisfy the requirements set by the representation of mode B. */
5765 static void
5766 init_num_sign_bit_copies_in_rep (void)
5768 opt_scalar_int_mode in_mode_iter;
5769 scalar_int_mode mode;
5771 FOR_EACH_MODE_IN_CLASS (in_mode_iter, MODE_INT)
5772 FOR_EACH_MODE_UNTIL (mode, in_mode_iter.require ())
5774 scalar_int_mode in_mode = in_mode_iter.require ();
5775 scalar_int_mode i;
5777 /* Currently, it is assumed that TARGET_MODE_REP_EXTENDED
5778 extends to the next widest mode. */
5779 gcc_assert (targetm.mode_rep_extended (mode, in_mode) == UNKNOWN
5780 || GET_MODE_WIDER_MODE (mode).require () == in_mode);
5782 /* We are in in_mode. Count how many bits outside of mode
5783 have to be copies of the sign-bit. */
5784 FOR_EACH_MODE (i, mode, in_mode)
5786 /* This must always exist (for the last iteration it will be
5787 IN_MODE). */
5788 scalar_int_mode wider = GET_MODE_WIDER_MODE (i).require ();
5790 if (targetm.mode_rep_extended (i, wider) == SIGN_EXTEND
5791 /* We can only check sign-bit copies starting from the
5792 top-bit. In order to be able to check the bits we
5793 have already seen we pretend that subsequent bits
5794 have to be sign-bit copies too. */
5795 || num_sign_bit_copies_in_rep [in_mode][mode])
5796 num_sign_bit_copies_in_rep [in_mode][mode]
5797 += GET_MODE_PRECISION (wider) - GET_MODE_PRECISION (i);
5802 /* Suppose that truncation from the machine mode of X to MODE is not a
5803 no-op. See if there is anything special about X so that we can
5804 assume it already contains a truncated value of MODE. */
5806 bool
5807 truncated_to_mode (machine_mode mode, const_rtx x)
5809 /* This register has already been used in MODE without explicit
5810 truncation. */
5811 if (REG_P (x) && rtl_hooks.reg_truncated_to_mode (mode, x))
5812 return true;
5814 /* See if we already satisfy the requirements of MODE. If yes we
5815 can just switch to MODE. */
5816 if (num_sign_bit_copies_in_rep[GET_MODE (x)][mode]
5817 && (num_sign_bit_copies (x, GET_MODE (x))
5818 >= num_sign_bit_copies_in_rep[GET_MODE (x)][mode] + 1))
5819 return true;
5821 return false;
5824 /* Return true if RTX code CODE has a single sequence of zero or more
5825 "e" operands and no rtvec operands. Initialize its rtx_all_subrtx_bounds
5826 entry in that case. */
5828 static bool
5829 setup_reg_subrtx_bounds (unsigned int code)
5831 const char *format = GET_RTX_FORMAT ((enum rtx_code) code);
5832 unsigned int i = 0;
5833 for (; format[i] != 'e'; ++i)
5835 if (!format[i])
5836 /* No subrtxes. Leave start and count as 0. */
5837 return true;
5838 if (format[i] == 'E' || format[i] == 'V')
5839 return false;
5842 /* Record the sequence of 'e's. */
5843 rtx_all_subrtx_bounds[code].start = i;
5845 ++i;
5846 while (format[i] == 'e');
5847 rtx_all_subrtx_bounds[code].count = i - rtx_all_subrtx_bounds[code].start;
5848 /* rtl-iter.h relies on this. */
5849 gcc_checking_assert (rtx_all_subrtx_bounds[code].count <= 3);
5851 for (; format[i]; ++i)
5852 if (format[i] == 'E' || format[i] == 'V' || format[i] == 'e')
5853 return false;
5855 return true;
5858 /* Initialize rtx_all_subrtx_bounds. */
5859 void
5860 init_rtlanal (void)
5862 int i;
5863 for (i = 0; i < NUM_RTX_CODE; i++)
5865 if (!setup_reg_subrtx_bounds (i))
5866 rtx_all_subrtx_bounds[i].count = UCHAR_MAX;
5867 if (GET_RTX_CLASS (i) != RTX_CONST_OBJ)
5868 rtx_nonconst_subrtx_bounds[i] = rtx_all_subrtx_bounds[i];
5871 init_num_sign_bit_copies_in_rep ();
5874 /* Check whether this is a constant pool constant. */
5875 bool
5876 constant_pool_constant_p (rtx x)
5878 x = avoid_constant_pool_reference (x);
5879 return CONST_DOUBLE_P (x);
5882 /* If M is a bitmask that selects a field of low-order bits within an item but
5883 not the entire word, return the length of the field. Return -1 otherwise.
5884 M is used in machine mode MODE. */
5887 low_bitmask_len (machine_mode mode, unsigned HOST_WIDE_INT m)
5889 if (mode != VOIDmode)
5891 if (!HWI_COMPUTABLE_MODE_P (mode))
5892 return -1;
5893 m &= GET_MODE_MASK (mode);
5896 return exact_log2 (m + 1);
5899 /* Return the mode of MEM's address. */
5901 scalar_int_mode
5902 get_address_mode (rtx mem)
5904 machine_mode mode;
5906 gcc_assert (MEM_P (mem));
5907 mode = GET_MODE (XEXP (mem, 0));
5908 if (mode != VOIDmode)
5909 return as_a <scalar_int_mode> (mode);
5910 return targetm.addr_space.address_mode (MEM_ADDR_SPACE (mem));
5913 /* Split up a CONST_DOUBLE or integer constant rtx
5914 into two rtx's for single words,
5915 storing in *FIRST the word that comes first in memory in the target
5916 and in *SECOND the other.
5918 TODO: This function needs to be rewritten to work on any size
5919 integer. */
5921 void
5922 split_double (rtx value, rtx *first, rtx *second)
5924 if (CONST_INT_P (value))
5926 if (HOST_BITS_PER_WIDE_INT >= (2 * BITS_PER_WORD))
5928 /* In this case the CONST_INT holds both target words.
5929 Extract the bits from it into two word-sized pieces.
5930 Sign extend each half to HOST_WIDE_INT. */
5931 unsigned HOST_WIDE_INT low, high;
5932 unsigned HOST_WIDE_INT mask, sign_bit, sign_extend;
5933 unsigned bits_per_word = BITS_PER_WORD;
5935 /* Set sign_bit to the most significant bit of a word. */
5936 sign_bit = 1;
5937 sign_bit <<= bits_per_word - 1;
5939 /* Set mask so that all bits of the word are set. We could
5940 have used 1 << BITS_PER_WORD instead of basing the
5941 calculation on sign_bit. However, on machines where
5942 HOST_BITS_PER_WIDE_INT == BITS_PER_WORD, it could cause a
5943 compiler warning, even though the code would never be
5944 executed. */
5945 mask = sign_bit << 1;
5946 mask--;
5948 /* Set sign_extend as any remaining bits. */
5949 sign_extend = ~mask;
5951 /* Pick the lower word and sign-extend it. */
5952 low = INTVAL (value);
5953 low &= mask;
5954 if (low & sign_bit)
5955 low |= sign_extend;
5957 /* Pick the higher word, shifted to the least significant
5958 bits, and sign-extend it. */
5959 high = INTVAL (value);
5960 high >>= bits_per_word - 1;
5961 high >>= 1;
5962 high &= mask;
5963 if (high & sign_bit)
5964 high |= sign_extend;
5966 /* Store the words in the target machine order. */
5967 if (WORDS_BIG_ENDIAN)
5969 *first = GEN_INT (high);
5970 *second = GEN_INT (low);
5972 else
5974 *first = GEN_INT (low);
5975 *second = GEN_INT (high);
5978 else
5980 /* The rule for using CONST_INT for a wider mode
5981 is that we regard the value as signed.
5982 So sign-extend it. */
5983 rtx high = (INTVAL (value) < 0 ? constm1_rtx : const0_rtx);
5984 if (WORDS_BIG_ENDIAN)
5986 *first = high;
5987 *second = value;
5989 else
5991 *first = value;
5992 *second = high;
5996 else if (GET_CODE (value) == CONST_WIDE_INT)
5998 /* All of this is scary code and needs to be converted to
5999 properly work with any size integer. */
6000 gcc_assert (CONST_WIDE_INT_NUNITS (value) == 2);
6001 if (WORDS_BIG_ENDIAN)
6003 *first = GEN_INT (CONST_WIDE_INT_ELT (value, 1));
6004 *second = GEN_INT (CONST_WIDE_INT_ELT (value, 0));
6006 else
6008 *first = GEN_INT (CONST_WIDE_INT_ELT (value, 0));
6009 *second = GEN_INT (CONST_WIDE_INT_ELT (value, 1));
6012 else if (!CONST_DOUBLE_P (value))
6014 if (WORDS_BIG_ENDIAN)
6016 *first = const0_rtx;
6017 *second = value;
6019 else
6021 *first = value;
6022 *second = const0_rtx;
6025 else if (GET_MODE (value) == VOIDmode
6026 /* This is the old way we did CONST_DOUBLE integers. */
6027 || GET_MODE_CLASS (GET_MODE (value)) == MODE_INT)
6029 /* In an integer, the words are defined as most and least significant.
6030 So order them by the target's convention. */
6031 if (WORDS_BIG_ENDIAN)
6033 *first = GEN_INT (CONST_DOUBLE_HIGH (value));
6034 *second = GEN_INT (CONST_DOUBLE_LOW (value));
6036 else
6038 *first = GEN_INT (CONST_DOUBLE_LOW (value));
6039 *second = GEN_INT (CONST_DOUBLE_HIGH (value));
6042 else
6044 long l[2];
6046 /* Note, this converts the REAL_VALUE_TYPE to the target's
6047 format, splits up the floating point double and outputs
6048 exactly 32 bits of it into each of l[0] and l[1] --
6049 not necessarily BITS_PER_WORD bits. */
6050 REAL_VALUE_TO_TARGET_DOUBLE (*CONST_DOUBLE_REAL_VALUE (value), l);
6052 /* If 32 bits is an entire word for the target, but not for the host,
6053 then sign-extend on the host so that the number will look the same
6054 way on the host that it would on the target. See for instance
6055 simplify_unary_operation. The #if is needed to avoid compiler
6056 warnings. */
6058 #if HOST_BITS_PER_LONG > 32
6059 if (BITS_PER_WORD < HOST_BITS_PER_LONG && BITS_PER_WORD == 32)
6061 if (l[0] & ((long) 1 << 31))
6062 l[0] |= ((unsigned long) (-1) << 32);
6063 if (l[1] & ((long) 1 << 31))
6064 l[1] |= ((unsigned long) (-1) << 32);
6066 #endif
6068 *first = GEN_INT (l[0]);
6069 *second = GEN_INT (l[1]);
6073 /* Return true if X is a sign_extract or zero_extract from the least
6074 significant bit. */
6076 static bool
6077 lsb_bitfield_op_p (rtx x)
6079 if (GET_RTX_CLASS (GET_CODE (x)) == RTX_BITFIELD_OPS)
6081 machine_mode mode = GET_MODE (XEXP (x, 0));
6082 HOST_WIDE_INT len = INTVAL (XEXP (x, 1));
6083 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
6084 poly_int64 remaining_bits = GET_MODE_PRECISION (mode) - len;
6086 return known_eq (pos, BITS_BIG_ENDIAN ? remaining_bits : 0);
6088 return false;
6091 /* Strip outer address "mutations" from LOC and return a pointer to the
6092 inner value. If OUTER_CODE is nonnull, store the code of the innermost
6093 stripped expression there.
6095 "Mutations" either convert between modes or apply some kind of
6096 extension, truncation or alignment. */
6098 rtx *
6099 strip_address_mutations (rtx *loc, enum rtx_code *outer_code)
6101 for (;;)
6103 enum rtx_code code = GET_CODE (*loc);
6104 if (GET_RTX_CLASS (code) == RTX_UNARY)
6105 /* Things like SIGN_EXTEND, ZERO_EXTEND and TRUNCATE can be
6106 used to convert between pointer sizes. */
6107 loc = &XEXP (*loc, 0);
6108 else if (lsb_bitfield_op_p (*loc))
6109 /* A [SIGN|ZERO]_EXTRACT from the least significant bit effectively
6110 acts as a combined truncation and extension. */
6111 loc = &XEXP (*loc, 0);
6112 else if (code == AND && CONST_INT_P (XEXP (*loc, 1)))
6113 /* (and ... (const_int -X)) is used to align to X bytes. */
6114 loc = &XEXP (*loc, 0);
6115 else if (code == SUBREG
6116 && !OBJECT_P (SUBREG_REG (*loc))
6117 && subreg_lowpart_p (*loc))
6118 /* (subreg (operator ...) ...) inside and is used for mode
6119 conversion too. */
6120 loc = &SUBREG_REG (*loc);
6121 else
6122 return loc;
6123 if (outer_code)
6124 *outer_code = code;
6128 /* Return true if CODE applies some kind of scale. The scaled value is
6129 is the first operand and the scale is the second. */
6131 static bool
6132 binary_scale_code_p (enum rtx_code code)
6134 return (code == MULT
6135 || code == ASHIFT
6136 /* Needed by ARM targets. */
6137 || code == ASHIFTRT
6138 || code == LSHIFTRT
6139 || code == ROTATE
6140 || code == ROTATERT);
6143 /* If *INNER can be interpreted as a base, return a pointer to the inner term
6144 (see address_info). Return null otherwise. */
6146 static rtx *
6147 get_base_term (rtx *inner)
6149 if (GET_CODE (*inner) == LO_SUM)
6150 inner = strip_address_mutations (&XEXP (*inner, 0));
6151 if (REG_P (*inner)
6152 || MEM_P (*inner)
6153 || GET_CODE (*inner) == SUBREG
6154 || GET_CODE (*inner) == SCRATCH)
6155 return inner;
6156 return 0;
6159 /* If *INNER can be interpreted as an index, return a pointer to the inner term
6160 (see address_info). Return null otherwise. */
6162 static rtx *
6163 get_index_term (rtx *inner)
6165 /* At present, only constant scales are allowed. */
6166 if (binary_scale_code_p (GET_CODE (*inner)) && CONSTANT_P (XEXP (*inner, 1)))
6167 inner = strip_address_mutations (&XEXP (*inner, 0));
6168 if (REG_P (*inner)
6169 || MEM_P (*inner)
6170 || GET_CODE (*inner) == SUBREG
6171 || GET_CODE (*inner) == SCRATCH)
6172 return inner;
6173 return 0;
6176 /* Set the segment part of address INFO to LOC, given that INNER is the
6177 unmutated value. */
6179 static void
6180 set_address_segment (struct address_info *info, rtx *loc, rtx *inner)
6182 gcc_assert (!info->segment);
6183 info->segment = loc;
6184 info->segment_term = inner;
6187 /* Set the base part of address INFO to LOC, given that INNER is the
6188 unmutated value. */
6190 static void
6191 set_address_base (struct address_info *info, rtx *loc, rtx *inner)
6193 gcc_assert (!info->base);
6194 info->base = loc;
6195 info->base_term = inner;
6198 /* Set the index part of address INFO to LOC, given that INNER is the
6199 unmutated value. */
6201 static void
6202 set_address_index (struct address_info *info, rtx *loc, rtx *inner)
6204 gcc_assert (!info->index);
6205 info->index = loc;
6206 info->index_term = inner;
6209 /* Set the displacement part of address INFO to LOC, given that INNER
6210 is the constant term. */
6212 static void
6213 set_address_disp (struct address_info *info, rtx *loc, rtx *inner)
6215 gcc_assert (!info->disp);
6216 info->disp = loc;
6217 info->disp_term = inner;
6220 /* INFO->INNER describes a {PRE,POST}_{INC,DEC} address. Set up the
6221 rest of INFO accordingly. */
6223 static void
6224 decompose_incdec_address (struct address_info *info)
6226 info->autoinc_p = true;
6228 rtx *base = &XEXP (*info->inner, 0);
6229 set_address_base (info, base, base);
6230 gcc_checking_assert (info->base == info->base_term);
6232 /* These addresses are only valid when the size of the addressed
6233 value is known. */
6234 gcc_checking_assert (info->mode != VOIDmode);
6237 /* INFO->INNER describes a {PRE,POST}_MODIFY address. Set up the rest
6238 of INFO accordingly. */
6240 static void
6241 decompose_automod_address (struct address_info *info)
6243 info->autoinc_p = true;
6245 rtx *base = &XEXP (*info->inner, 0);
6246 set_address_base (info, base, base);
6247 gcc_checking_assert (info->base == info->base_term);
6249 rtx plus = XEXP (*info->inner, 1);
6250 gcc_assert (GET_CODE (plus) == PLUS);
6252 info->base_term2 = &XEXP (plus, 0);
6253 gcc_checking_assert (rtx_equal_p (*info->base_term, *info->base_term2));
6255 rtx *step = &XEXP (plus, 1);
6256 rtx *inner_step = strip_address_mutations (step);
6257 if (CONSTANT_P (*inner_step))
6258 set_address_disp (info, step, inner_step);
6259 else
6260 set_address_index (info, step, inner_step);
6263 /* Treat *LOC as a tree of PLUS operands and store pointers to the summed
6264 values in [PTR, END). Return a pointer to the end of the used array. */
6266 static rtx **
6267 extract_plus_operands (rtx *loc, rtx **ptr, rtx **end)
6269 rtx x = *loc;
6270 if (GET_CODE (x) == PLUS)
6272 ptr = extract_plus_operands (&XEXP (x, 0), ptr, end);
6273 ptr = extract_plus_operands (&XEXP (x, 1), ptr, end);
6275 else
6277 gcc_assert (ptr != end);
6278 *ptr++ = loc;
6280 return ptr;
6283 /* Evaluate the likelihood of X being a base or index value, returning
6284 positive if it is likely to be a base, negative if it is likely to be
6285 an index, and 0 if we can't tell. Make the magnitude of the return
6286 value reflect the amount of confidence we have in the answer.
6288 MODE, AS, OUTER_CODE and INDEX_CODE are as for ok_for_base_p_1. */
6290 static int
6291 baseness (rtx x, machine_mode mode, addr_space_t as,
6292 enum rtx_code outer_code, enum rtx_code index_code)
6294 /* Believe *_POINTER unless the address shape requires otherwise. */
6295 if (REG_P (x) && REG_POINTER (x))
6296 return 2;
6297 if (MEM_P (x) && MEM_POINTER (x))
6298 return 2;
6300 if (REG_P (x) && HARD_REGISTER_P (x))
6302 /* X is a hard register. If it only fits one of the base
6303 or index classes, choose that interpretation. */
6304 int regno = REGNO (x);
6305 bool base_p = ok_for_base_p_1 (regno, mode, as, outer_code, index_code);
6306 bool index_p = REGNO_OK_FOR_INDEX_P (regno);
6307 if (base_p != index_p)
6308 return base_p ? 1 : -1;
6310 return 0;
6313 /* INFO->INNER describes a normal, non-automodified address.
6314 Fill in the rest of INFO accordingly. */
6316 static void
6317 decompose_normal_address (struct address_info *info)
6319 /* Treat the address as the sum of up to four values. */
6320 rtx *ops[4];
6321 size_t n_ops = extract_plus_operands (info->inner, ops,
6322 ops + ARRAY_SIZE (ops)) - ops;
6324 /* If there is more than one component, any base component is in a PLUS. */
6325 if (n_ops > 1)
6326 info->base_outer_code = PLUS;
6328 /* Try to classify each sum operand now. Leave those that could be
6329 either a base or an index in OPS. */
6330 rtx *inner_ops[4];
6331 size_t out = 0;
6332 for (size_t in = 0; in < n_ops; ++in)
6334 rtx *loc = ops[in];
6335 rtx *inner = strip_address_mutations (loc);
6336 if (CONSTANT_P (*inner))
6337 set_address_disp (info, loc, inner);
6338 else if (GET_CODE (*inner) == UNSPEC)
6339 set_address_segment (info, loc, inner);
6340 else
6342 /* The only other possibilities are a base or an index. */
6343 rtx *base_term = get_base_term (inner);
6344 rtx *index_term = get_index_term (inner);
6345 gcc_assert (base_term || index_term);
6346 if (!base_term)
6347 set_address_index (info, loc, index_term);
6348 else if (!index_term)
6349 set_address_base (info, loc, base_term);
6350 else
6352 gcc_assert (base_term == index_term);
6353 ops[out] = loc;
6354 inner_ops[out] = base_term;
6355 ++out;
6360 /* Classify the remaining OPS members as bases and indexes. */
6361 if (out == 1)
6363 /* If we haven't seen a base or an index yet, assume that this is
6364 the base. If we were confident that another term was the base
6365 or index, treat the remaining operand as the other kind. */
6366 if (!info->base)
6367 set_address_base (info, ops[0], inner_ops[0]);
6368 else
6369 set_address_index (info, ops[0], inner_ops[0]);
6371 else if (out == 2)
6373 /* In the event of a tie, assume the base comes first. */
6374 if (baseness (*inner_ops[0], info->mode, info->as, PLUS,
6375 GET_CODE (*ops[1]))
6376 >= baseness (*inner_ops[1], info->mode, info->as, PLUS,
6377 GET_CODE (*ops[0])))
6379 set_address_base (info, ops[0], inner_ops[0]);
6380 set_address_index (info, ops[1], inner_ops[1]);
6382 else
6384 set_address_base (info, ops[1], inner_ops[1]);
6385 set_address_index (info, ops[0], inner_ops[0]);
6388 else
6389 gcc_assert (out == 0);
6392 /* Describe address *LOC in *INFO. MODE is the mode of the addressed value,
6393 or VOIDmode if not known. AS is the address space associated with LOC.
6394 OUTER_CODE is MEM if *LOC is a MEM address and ADDRESS otherwise. */
6396 void
6397 decompose_address (struct address_info *info, rtx *loc, machine_mode mode,
6398 addr_space_t as, enum rtx_code outer_code)
6400 memset (info, 0, sizeof (*info));
6401 info->mode = mode;
6402 info->as = as;
6403 info->addr_outer_code = outer_code;
6404 info->outer = loc;
6405 info->inner = strip_address_mutations (loc, &outer_code);
6406 info->base_outer_code = outer_code;
6407 switch (GET_CODE (*info->inner))
6409 case PRE_DEC:
6410 case PRE_INC:
6411 case POST_DEC:
6412 case POST_INC:
6413 decompose_incdec_address (info);
6414 break;
6416 case PRE_MODIFY:
6417 case POST_MODIFY:
6418 decompose_automod_address (info);
6419 break;
6421 default:
6422 decompose_normal_address (info);
6423 break;
6427 /* Describe address operand LOC in INFO. */
6429 void
6430 decompose_lea_address (struct address_info *info, rtx *loc)
6432 decompose_address (info, loc, VOIDmode, ADDR_SPACE_GENERIC, ADDRESS);
6435 /* Describe the address of MEM X in INFO. */
6437 void
6438 decompose_mem_address (struct address_info *info, rtx x)
6440 gcc_assert (MEM_P (x));
6441 decompose_address (info, &XEXP (x, 0), GET_MODE (x),
6442 MEM_ADDR_SPACE (x), MEM);
6445 /* Update INFO after a change to the address it describes. */
6447 void
6448 update_address (struct address_info *info)
6450 decompose_address (info, info->outer, info->mode, info->as,
6451 info->addr_outer_code);
6454 /* Return the scale applied to *INFO->INDEX_TERM, or 0 if the index is
6455 more complicated than that. */
6457 HOST_WIDE_INT
6458 get_index_scale (const struct address_info *info)
6460 rtx index = *info->index;
6461 if (GET_CODE (index) == MULT
6462 && CONST_INT_P (XEXP (index, 1))
6463 && info->index_term == &XEXP (index, 0))
6464 return INTVAL (XEXP (index, 1));
6466 if (GET_CODE (index) == ASHIFT
6467 && CONST_INT_P (XEXP (index, 1))
6468 && info->index_term == &XEXP (index, 0))
6469 return HOST_WIDE_INT_1 << INTVAL (XEXP (index, 1));
6471 if (info->index == info->index_term)
6472 return 1;
6474 return 0;
6477 /* Return the "index code" of INFO, in the form required by
6478 ok_for_base_p_1. */
6480 enum rtx_code
6481 get_index_code (const struct address_info *info)
6483 if (info->index)
6484 return GET_CODE (*info->index);
6486 if (info->disp)
6487 return GET_CODE (*info->disp);
6489 return SCRATCH;
6492 /* Return true if RTL X contains a SYMBOL_REF. */
6494 bool
6495 contains_symbol_ref_p (const_rtx x)
6497 subrtx_iterator::array_type array;
6498 FOR_EACH_SUBRTX (iter, array, x, ALL)
6499 if (SYMBOL_REF_P (*iter))
6500 return true;
6502 return false;
6505 /* Return true if RTL X contains a SYMBOL_REF or LABEL_REF. */
6507 bool
6508 contains_symbolic_reference_p (const_rtx x)
6510 subrtx_iterator::array_type array;
6511 FOR_EACH_SUBRTX (iter, array, x, ALL)
6512 if (SYMBOL_REF_P (*iter) || GET_CODE (*iter) == LABEL_REF)
6513 return true;
6515 return false;
6518 /* Return true if X contains a thread-local symbol. */
6520 bool
6521 tls_referenced_p (const_rtx x)
6523 if (!targetm.have_tls)
6524 return false;
6526 subrtx_iterator::array_type array;
6527 FOR_EACH_SUBRTX (iter, array, x, ALL)
6528 if (GET_CODE (*iter) == SYMBOL_REF && SYMBOL_REF_TLS_MODEL (*iter) != 0)
6529 return true;
6530 return false;