1 /* Register renaming for the GNU compiler.
2 Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GCC is distributed in the hope that it will be useful, but WITHOUT
12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
14 License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING. If not, write to the Free
18 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
25 #include "coretypes.h"
29 #include "insn-config.h"
31 #include "hard-reg-set.h"
32 #include "basic-block.h"
41 #ifndef REG_MODE_OK_FOR_BASE_P
42 #define REG_MODE_OK_FOR_BASE_P(REGNO, MODE) REG_OK_FOR_BASE_P (REGNO)
45 static const char *const reg_class_names
[] = REG_CLASS_NAMES
;
49 struct du_chain
*next_chain
;
50 struct du_chain
*next_use
;
55 unsigned int need_caller_save_reg
:1;
56 unsigned int earlyclobber
:1;
62 terminate_overlapping_read
,
69 static const char * const scan_actions_name
[] =
72 "terminate_overlapping_read",
79 static struct obstack rename_obstack
;
81 static void do_replace
PARAMS ((struct du_chain
*, int));
82 static void scan_rtx_reg
PARAMS ((rtx
, rtx
*, enum reg_class
,
83 enum scan_actions
, enum op_type
, int));
84 static void scan_rtx_address
PARAMS ((rtx
, rtx
*, enum reg_class
,
85 enum scan_actions
, enum machine_mode
));
86 static void scan_rtx
PARAMS ((rtx
, rtx
*, enum reg_class
,
87 enum scan_actions
, enum op_type
, int));
88 static struct du_chain
*build_def_use
PARAMS ((basic_block
));
89 static void dump_def_use_chain
PARAMS ((struct du_chain
*));
90 static void note_sets
PARAMS ((rtx
, rtx
, void *));
91 static void clear_dead_regs
PARAMS ((HARD_REG_SET
*, enum machine_mode
, rtx
));
92 static void merge_overlapping_regs
PARAMS ((basic_block
, HARD_REG_SET
*,
95 /* Called through note_stores from update_life. Find sets of registers, and
96 record them in *DATA (which is actually a HARD_REG_SET *). */
99 note_sets (x
, set
, data
)
101 rtx set ATTRIBUTE_UNUSED
;
104 HARD_REG_SET
*pset
= (HARD_REG_SET
*) data
;
107 if (GET_CODE (x
) != REG
)
110 nregs
= HARD_REGNO_NREGS (regno
, GET_MODE (x
));
112 /* There must not be pseudos at this point. */
113 if (regno
+ nregs
> FIRST_PSEUDO_REGISTER
)
117 SET_HARD_REG_BIT (*pset
, regno
+ nregs
);
120 /* Clear all registers from *PSET for which a note of kind KIND can be found
121 in the list NOTES. */
124 clear_dead_regs (pset
, kind
, notes
)
126 enum machine_mode kind
;
130 for (note
= notes
; note
; note
= XEXP (note
, 1))
131 if (REG_NOTE_KIND (note
) == kind
&& REG_P (XEXP (note
, 0)))
133 rtx reg
= XEXP (note
, 0);
134 unsigned int regno
= REGNO (reg
);
135 int nregs
= HARD_REGNO_NREGS (regno
, GET_MODE (reg
));
137 /* There must not be pseudos at this point. */
138 if (regno
+ nregs
> FIRST_PSEUDO_REGISTER
)
142 CLEAR_HARD_REG_BIT (*pset
, regno
+ nregs
);
146 /* For a def-use chain CHAIN in basic block B, find which registers overlap
147 its lifetime and set the corresponding bits in *PSET. */
150 merge_overlapping_regs (b
, pset
, chain
)
153 struct du_chain
*chain
;
155 struct du_chain
*t
= chain
;
159 REG_SET_TO_HARD_REG_SET (live
, b
->global_live_at_start
);
163 /* Search forward until the next reference to the register to be
165 while (insn
!= t
->insn
)
169 clear_dead_regs (&live
, REG_DEAD
, REG_NOTES (insn
));
170 note_stores (PATTERN (insn
), note_sets
, (void *) &live
);
171 /* Only record currently live regs if we are inside the
174 IOR_HARD_REG_SET (*pset
, live
);
175 clear_dead_regs (&live
, REG_UNUSED
, REG_NOTES (insn
));
177 insn
= NEXT_INSN (insn
);
180 IOR_HARD_REG_SET (*pset
, live
);
182 /* For the last reference, also merge in all registers set in the
184 @@@ We only have take earlyclobbered sets into account. */
186 note_stores (PATTERN (insn
), note_sets
, (void *) pset
);
192 /* Perform register renaming on the current function. */
195 regrename_optimize ()
197 int tick
[FIRST_PSEUDO_REGISTER
];
202 memset (tick
, 0, sizeof tick
);
204 gcc_obstack_init (&rename_obstack
);
205 first_obj
= (char *) obstack_alloc (&rename_obstack
, 0);
209 struct du_chain
*all_chains
= 0;
210 HARD_REG_SET unavailable
;
211 HARD_REG_SET regs_seen
;
213 CLEAR_HARD_REG_SET (unavailable
);
216 fprintf (rtl_dump_file
, "\nBasic block %d:\n", bb
->index
);
218 all_chains
= build_def_use (bb
);
221 dump_def_use_chain (all_chains
);
223 CLEAR_HARD_REG_SET (unavailable
);
224 /* Don't clobber traceback for noreturn functions. */
225 if (frame_pointer_needed
)
229 for (i
= HARD_REGNO_NREGS (FRAME_POINTER_REGNUM
, Pmode
); i
--;)
230 SET_HARD_REG_BIT (unavailable
, FRAME_POINTER_REGNUM
+ i
);
232 #if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
233 for (i
= HARD_REGNO_NREGS (HARD_FRAME_POINTER_REGNUM
, Pmode
); i
--;)
234 SET_HARD_REG_BIT (unavailable
, HARD_FRAME_POINTER_REGNUM
+ i
);
238 CLEAR_HARD_REG_SET (regs_seen
);
241 int new_reg
, best_new_reg
= -1;
243 struct du_chain
*this = all_chains
;
244 struct du_chain
*tmp
, *last
;
245 HARD_REG_SET this_unavailable
;
246 int reg
= REGNO (*this->loc
);
249 all_chains
= this->next_chain
;
251 #if 0 /* This just disables optimization opportunities. */
252 /* Only rename once we've seen the reg more than once. */
253 if (! TEST_HARD_REG_BIT (regs_seen
, reg
))
255 SET_HARD_REG_BIT (regs_seen
, reg
);
260 if (fixed_regs
[reg
] || global_regs
[reg
]
261 #if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
262 || (frame_pointer_needed
&& reg
== HARD_FRAME_POINTER_REGNUM
)
264 || (frame_pointer_needed
&& reg
== FRAME_POINTER_REGNUM
)
269 COPY_HARD_REG_SET (this_unavailable
, unavailable
);
271 /* Find last entry on chain (which has the need_caller_save bit),
272 count number of uses, and narrow the set of registers we can
275 for (last
= this; last
->next_use
; last
= last
->next_use
)
278 IOR_COMPL_HARD_REG_SET (this_unavailable
,
279 reg_class_contents
[last
->class]);
284 IOR_COMPL_HARD_REG_SET (this_unavailable
,
285 reg_class_contents
[last
->class]);
287 if (this->need_caller_save_reg
)
288 IOR_HARD_REG_SET (this_unavailable
, call_used_reg_set
);
290 merge_overlapping_regs (bb
, &this_unavailable
, this);
292 /* Now potential_regs is a reasonable approximation, let's
293 have a closer look at each register still in there. */
294 for (new_reg
= 0; new_reg
< FIRST_PSEUDO_REGISTER
; new_reg
++)
296 int nregs
= HARD_REGNO_NREGS (new_reg
, GET_MODE (*this->loc
));
298 for (i
= nregs
- 1; i
>= 0; --i
)
299 if (TEST_HARD_REG_BIT (this_unavailable
, new_reg
+ i
)
300 || fixed_regs
[new_reg
+ i
]
301 || global_regs
[new_reg
+ i
]
302 /* Can't use regs which aren't saved by the prologue. */
303 || (! regs_ever_live
[new_reg
+ i
]
304 && ! call_used_regs
[new_reg
+ i
])
305 #ifdef LEAF_REGISTERS
306 /* We can't use a non-leaf register if we're in a
308 || (current_function_is_leaf
309 && !LEAF_REGISTERS
[new_reg
+ i
])
311 #ifdef HARD_REGNO_RENAME_OK
312 || ! HARD_REGNO_RENAME_OK (reg
+ i
, new_reg
+ i
)
319 /* See whether it accepts all modes that occur in
320 definition and uses. */
321 for (tmp
= this; tmp
; tmp
= tmp
->next_use
)
322 if (! HARD_REGNO_MODE_OK (new_reg
, GET_MODE (*tmp
->loc
))
323 || (tmp
->need_caller_save_reg
324 && ! (HARD_REGNO_CALL_PART_CLOBBERED
325 (reg
, GET_MODE (*tmp
->loc
)))
326 && (HARD_REGNO_CALL_PART_CLOBBERED
327 (new_reg
, GET_MODE (*tmp
->loc
)))))
331 if (best_new_reg
== -1
332 || tick
[best_new_reg
] > tick
[new_reg
])
333 best_new_reg
= new_reg
;
339 fprintf (rtl_dump_file
, "Register %s in insn %d",
340 reg_names
[reg
], INSN_UID (last
->insn
));
341 if (last
->need_caller_save_reg
)
342 fprintf (rtl_dump_file
, " crosses a call");
345 if (best_new_reg
== -1)
348 fprintf (rtl_dump_file
, "; no available registers\n");
352 do_replace (this, best_new_reg
);
353 tick
[best_new_reg
] = this_tick
++;
356 fprintf (rtl_dump_file
, ", renamed as %s\n", reg_names
[best_new_reg
]);
359 obstack_free (&rename_obstack
, first_obj
);
362 obstack_free (&rename_obstack
, NULL
);
365 fputc ('\n', rtl_dump_file
);
367 count_or_remove_death_notes (NULL
, 1);
368 update_life_info (NULL
, UPDATE_LIFE_LOCAL
,
369 PROP_REG_INFO
| PROP_DEATH_NOTES
);
373 do_replace (chain
, reg
)
374 struct du_chain
*chain
;
379 unsigned int regno
= ORIGINAL_REGNO (*chain
->loc
);
380 struct reg_attrs
* attr
= REG_ATTRS (*chain
->loc
);
382 *chain
->loc
= gen_raw_REG (GET_MODE (*chain
->loc
), reg
);
383 if (regno
>= FIRST_PSEUDO_REGISTER
)
384 ORIGINAL_REGNO (*chain
->loc
) = regno
;
385 REG_ATTRS (*chain
->loc
) = attr
;
386 chain
= chain
->next_use
;
391 static struct du_chain
*open_chains
;
392 static struct du_chain
*closed_chains
;
395 scan_rtx_reg (insn
, loc
, class, action
, type
, earlyclobber
)
398 enum reg_class
class;
399 enum scan_actions action
;
405 enum machine_mode mode
= GET_MODE (x
);
406 int this_regno
= REGNO (x
);
407 int this_nregs
= HARD_REGNO_NREGS (this_regno
, mode
);
409 if (action
== mark_write
)
413 struct du_chain
*this = (struct du_chain
*)
414 obstack_alloc (&rename_obstack
, sizeof (struct du_chain
));
416 this->next_chain
= open_chains
;
420 this->need_caller_save_reg
= 0;
421 this->earlyclobber
= earlyclobber
;
427 if ((type
== OP_OUT
&& action
!= terminate_write
)
428 || (type
!= OP_OUT
&& action
== terminate_write
))
431 for (p
= &open_chains
; *p
;)
433 struct du_chain
*this = *p
;
435 /* Check if the chain has been terminated if it has then skip to
438 This can happen when we've already appended the location to
439 the chain in Step 3, but are trying to hide in-out operands
440 from terminate_write in Step 5. */
442 if (*this->loc
== cc0_rtx
)
443 p
= &this->next_chain
;
446 int regno
= REGNO (*this->loc
);
447 int nregs
= HARD_REGNO_NREGS (regno
, GET_MODE (*this->loc
));
448 int exact_match
= (regno
== this_regno
&& nregs
== this_nregs
);
450 if (regno
+ nregs
<= this_regno
451 || this_regno
+ this_nregs
<= regno
)
453 p
= &this->next_chain
;
457 if (action
== mark_read
)
462 /* ??? Class NO_REGS can happen if the md file makes use of
463 EXTRA_CONSTRAINTS to match registers. Which is arguably
464 wrong, but there we are. Since we know not what this may
465 be replaced with, terminate the chain. */
466 if (class != NO_REGS
)
468 this = (struct du_chain
*)
469 obstack_alloc (&rename_obstack
, sizeof (struct du_chain
));
471 this->next_chain
= (*p
)->next_chain
;
475 this->need_caller_save_reg
= 0;
483 if (action
!= terminate_overlapping_read
|| ! exact_match
)
485 struct du_chain
*next
= this->next_chain
;
487 /* Whether the terminated chain can be used for renaming
488 depends on the action and this being an exact match.
489 In either case, we remove this element from open_chains. */
491 if ((action
== terminate_dead
|| action
== terminate_write
)
494 this->next_chain
= closed_chains
;
495 closed_chains
= this;
497 fprintf (rtl_dump_file
,
498 "Closing chain %s at insn %d (%s)\n",
499 reg_names
[REGNO (*this->loc
)], INSN_UID (insn
),
500 scan_actions_name
[(int) action
]);
505 fprintf (rtl_dump_file
,
506 "Discarding chain %s at insn %d (%s)\n",
507 reg_names
[REGNO (*this->loc
)], INSN_UID (insn
),
508 scan_actions_name
[(int) action
]);
513 p
= &this->next_chain
;
518 /* Adapted from find_reloads_address_1. CLASS is INDEX_REG_CLASS or
519 BASE_REG_CLASS depending on how the register is being considered. */
522 scan_rtx_address (insn
, loc
, class, action
, mode
)
525 enum reg_class
class;
526 enum scan_actions action
;
527 enum machine_mode mode
;
530 RTX_CODE code
= GET_CODE (x
);
534 if (action
== mark_write
)
541 rtx orig_op0
= XEXP (x
, 0);
542 rtx orig_op1
= XEXP (x
, 1);
543 RTX_CODE code0
= GET_CODE (orig_op0
);
544 RTX_CODE code1
= GET_CODE (orig_op1
);
550 if (GET_CODE (op0
) == SUBREG
)
552 op0
= SUBREG_REG (op0
);
553 code0
= GET_CODE (op0
);
556 if (GET_CODE (op1
) == SUBREG
)
558 op1
= SUBREG_REG (op1
);
559 code1
= GET_CODE (op1
);
562 if (code0
== MULT
|| code0
== SIGN_EXTEND
|| code0
== TRUNCATE
563 || code0
== ZERO_EXTEND
|| code1
== MEM
)
568 else if (code1
== MULT
|| code1
== SIGN_EXTEND
|| code1
== TRUNCATE
569 || code1
== ZERO_EXTEND
|| code0
== MEM
)
574 else if (code0
== CONST_INT
|| code0
== CONST
575 || code0
== SYMBOL_REF
|| code0
== LABEL_REF
)
577 else if (code1
== CONST_INT
|| code1
== CONST
578 || code1
== SYMBOL_REF
|| code1
== LABEL_REF
)
580 else if (code0
== REG
&& code1
== REG
)
584 if (REG_OK_FOR_INDEX_P (op0
)
585 && REG_MODE_OK_FOR_BASE_P (op1
, mode
))
587 else if (REG_OK_FOR_INDEX_P (op1
)
588 && REG_MODE_OK_FOR_BASE_P (op0
, mode
))
590 else if (REG_MODE_OK_FOR_BASE_P (op1
, mode
))
592 else if (REG_MODE_OK_FOR_BASE_P (op0
, mode
))
594 else if (REG_OK_FOR_INDEX_P (op1
))
599 locI
= &XEXP (x
, index_op
);
600 locB
= &XEXP (x
, !index_op
);
602 else if (code0
== REG
)
607 else if (code1
== REG
)
614 scan_rtx_address (insn
, locI
, INDEX_REG_CLASS
, action
, mode
);
616 scan_rtx_address (insn
, locB
, MODE_BASE_REG_CLASS (mode
), action
, mode
);
627 /* If the target doesn't claim to handle autoinc, this must be
628 something special, like a stack push. Kill this chain. */
629 action
= terminate_all_read
;
634 scan_rtx_address (insn
, &XEXP (x
, 0),
635 MODE_BASE_REG_CLASS (GET_MODE (x
)), action
,
640 scan_rtx_reg (insn
, loc
, class, action
, OP_IN
, 0);
647 fmt
= GET_RTX_FORMAT (code
);
648 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
651 scan_rtx_address (insn
, &XEXP (x
, i
), class, action
, mode
);
652 else if (fmt
[i
] == 'E')
653 for (j
= XVECLEN (x
, i
) - 1; j
>= 0; j
--)
654 scan_rtx_address (insn
, &XVECEXP (x
, i
, j
), class, action
, mode
);
659 scan_rtx (insn
, loc
, class, action
, type
, earlyclobber
)
662 enum reg_class
class;
663 enum scan_actions action
;
669 enum rtx_code code
= GET_CODE (x
);
686 scan_rtx_reg (insn
, loc
, class, action
, type
, earlyclobber
);
690 scan_rtx_address (insn
, &XEXP (x
, 0),
691 MODE_BASE_REG_CLASS (GET_MODE (x
)), action
,
696 scan_rtx (insn
, &SET_SRC (x
), class, action
, OP_IN
, 0);
697 scan_rtx (insn
, &SET_DEST (x
), class, action
, OP_OUT
, 0);
700 case STRICT_LOW_PART
:
701 scan_rtx (insn
, &XEXP (x
, 0), class, action
, OP_INOUT
, earlyclobber
);
706 scan_rtx (insn
, &XEXP (x
, 0), class, action
,
707 type
== OP_IN
? OP_IN
: OP_INOUT
, earlyclobber
);
708 scan_rtx (insn
, &XEXP (x
, 1), class, action
, OP_IN
, 0);
709 scan_rtx (insn
, &XEXP (x
, 2), class, action
, OP_IN
, 0);
718 /* Should only happen inside MEM. */
722 scan_rtx (insn
, &SET_DEST (x
), class, action
, OP_OUT
, 1);
726 scan_rtx (insn
, &XEXP (x
, 0), class, action
, type
, 0);
728 scan_rtx (insn
, &XEXP (x
, 1), class, action
, type
, 0);
735 fmt
= GET_RTX_FORMAT (code
);
736 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
739 scan_rtx (insn
, &XEXP (x
, i
), class, action
, type
, 0);
740 else if (fmt
[i
] == 'E')
741 for (j
= XVECLEN (x
, i
) - 1; j
>= 0; j
--)
742 scan_rtx (insn
, &XVECEXP (x
, i
, j
), class, action
, type
, 0);
746 /* Build def/use chain. */
748 static struct du_chain
*
754 open_chains
= closed_chains
= NULL
;
756 for (insn
= bb
->head
; ; insn
= NEXT_INSN (insn
))
762 rtx old_operands
[MAX_RECOG_OPERANDS
];
763 rtx old_dups
[MAX_DUP_OPERANDS
];
768 /* Process the insn, determining its effect on the def-use
769 chains. We perform the following steps with the register
770 references in the insn:
771 (1) Any read that overlaps an open chain, but doesn't exactly
772 match, causes that chain to be closed. We can't deal
774 (2) Any read outside an operand causes any chain it overlaps
775 with to be closed, since we can't replace it.
776 (3) Any read inside an operand is added if there's already
777 an open chain for it.
778 (4) For any REG_DEAD note we find, close open chains that
780 (5) For any write we find, close open chains that overlap it.
781 (6) For any write we find in an operand, make a new chain.
782 (7) For any REG_UNUSED, close any chains we just opened. */
784 icode
= recog_memoized (insn
);
786 if (! constrain_operands (1))
787 fatal_insn_not_found (insn
);
788 preprocess_constraints ();
789 alt
= which_alternative
;
790 n_ops
= recog_data
.n_operands
;
792 /* Simplify the code below by rewriting things to reflect
793 matching constraints. Also promote OP_OUT to OP_INOUT
794 in predicated instructions. */
796 predicated
= GET_CODE (PATTERN (insn
)) == COND_EXEC
;
797 for (i
= 0; i
< n_ops
; ++i
)
799 int matches
= recog_op_alt
[i
][alt
].matches
;
801 recog_op_alt
[i
][alt
].class = recog_op_alt
[matches
][alt
].class;
802 if (matches
>= 0 || recog_op_alt
[i
][alt
].matched
>= 0
803 || (predicated
&& recog_data
.operand_type
[i
] == OP_OUT
))
804 recog_data
.operand_type
[i
] = OP_INOUT
;
807 /* Step 1: Close chains for which we have overlapping reads. */
808 for (i
= 0; i
< n_ops
; i
++)
809 scan_rtx (insn
, recog_data
.operand_loc
[i
],
810 NO_REGS
, terminate_overlapping_read
,
811 recog_data
.operand_type
[i
], 0);
813 /* Step 2: Close chains for which we have reads outside operands.
814 We do this by munging all operands into CC0, and closing
815 everything remaining. */
817 for (i
= 0; i
< n_ops
; i
++)
819 old_operands
[i
] = recog_data
.operand
[i
];
820 /* Don't squash match_operator or match_parallel here, since
821 we don't know that all of the contained registers are
822 reachable by proper operands. */
823 if (recog_data
.constraints
[i
][0] == '\0')
825 *recog_data
.operand_loc
[i
] = cc0_rtx
;
827 for (i
= 0; i
< recog_data
.n_dups
; i
++)
829 int dup_num
= recog_data
.dup_num
[i
];
831 old_dups
[i
] = *recog_data
.dup_loc
[i
];
832 *recog_data
.dup_loc
[i
] = cc0_rtx
;
834 /* For match_dup of match_operator or match_parallel, share
835 them, so that we don't miss changes in the dup. */
837 && insn_data
[icode
].operand
[dup_num
].eliminable
== 0)
838 old_dups
[i
] = recog_data
.operand
[dup_num
];
841 scan_rtx (insn
, &PATTERN (insn
), NO_REGS
, terminate_all_read
,
844 for (i
= 0; i
< recog_data
.n_dups
; i
++)
845 *recog_data
.dup_loc
[i
] = old_dups
[i
];
846 for (i
= 0; i
< n_ops
; i
++)
847 *recog_data
.operand_loc
[i
] = old_operands
[i
];
849 /* Step 2B: Can't rename function call argument registers. */
850 if (GET_CODE (insn
) == CALL_INSN
&& CALL_INSN_FUNCTION_USAGE (insn
))
851 scan_rtx (insn
, &CALL_INSN_FUNCTION_USAGE (insn
),
852 NO_REGS
, terminate_all_read
, OP_IN
, 0);
854 /* Step 2C: Can't rename asm operands that were originally
856 if (asm_noperands (PATTERN (insn
)) > 0)
857 for (i
= 0; i
< n_ops
; i
++)
859 rtx
*loc
= recog_data
.operand_loc
[i
];
862 if (GET_CODE (op
) == REG
863 && REGNO (op
) == ORIGINAL_REGNO (op
)
864 && (recog_data
.operand_type
[i
] == OP_IN
865 || recog_data
.operand_type
[i
] == OP_INOUT
))
866 scan_rtx (insn
, loc
, NO_REGS
, terminate_all_read
, OP_IN
, 0);
869 /* Step 3: Append to chains for reads inside operands. */
870 for (i
= 0; i
< n_ops
+ recog_data
.n_dups
; i
++)
872 int opn
= i
< n_ops
? i
: recog_data
.dup_num
[i
- n_ops
];
873 rtx
*loc
= (i
< n_ops
874 ? recog_data
.operand_loc
[opn
]
875 : recog_data
.dup_loc
[i
- n_ops
]);
876 enum reg_class
class = recog_op_alt
[opn
][alt
].class;
877 enum op_type type
= recog_data
.operand_type
[opn
];
879 /* Don't scan match_operand here, since we've no reg class
880 information to pass down. Any operands that we could
881 substitute in will be represented elsewhere. */
882 if (recog_data
.constraints
[opn
][0] == '\0')
885 if (recog_op_alt
[opn
][alt
].is_address
)
886 scan_rtx_address (insn
, loc
, class, mark_read
, VOIDmode
);
888 scan_rtx (insn
, loc
, class, mark_read
, type
, 0);
891 /* Step 4: Close chains for registers that die here.
892 Also record updates for REG_INC notes. */
893 for (note
= REG_NOTES (insn
); note
; note
= XEXP (note
, 1))
895 if (REG_NOTE_KIND (note
) == REG_DEAD
)
896 scan_rtx (insn
, &XEXP (note
, 0), NO_REGS
, terminate_dead
,
898 else if (REG_NOTE_KIND (note
) == REG_INC
)
899 scan_rtx (insn
, &XEXP (note
, 0), ALL_REGS
, mark_read
,
903 /* Step 4B: If this is a call, any chain live at this point
904 requires a caller-saved reg. */
905 if (GET_CODE (insn
) == CALL_INSN
)
908 for (p
= open_chains
; p
; p
= p
->next_chain
)
909 p
->need_caller_save_reg
= 1;
912 /* Step 5: Close open chains that overlap writes. Similar to
913 step 2, we hide in-out operands, since we do not want to
914 close these chains. */
916 for (i
= 0; i
< n_ops
; i
++)
918 old_operands
[i
] = recog_data
.operand
[i
];
919 if (recog_data
.operand_type
[i
] == OP_INOUT
)
920 *recog_data
.operand_loc
[i
] = cc0_rtx
;
922 for (i
= 0; i
< recog_data
.n_dups
; i
++)
924 int opn
= recog_data
.dup_num
[i
];
925 old_dups
[i
] = *recog_data
.dup_loc
[i
];
926 if (recog_data
.operand_type
[opn
] == OP_INOUT
)
927 *recog_data
.dup_loc
[i
] = cc0_rtx
;
930 scan_rtx (insn
, &PATTERN (insn
), NO_REGS
, terminate_write
, OP_IN
, 0);
932 for (i
= 0; i
< recog_data
.n_dups
; i
++)
933 *recog_data
.dup_loc
[i
] = old_dups
[i
];
934 for (i
= 0; i
< n_ops
; i
++)
935 *recog_data
.operand_loc
[i
] = old_operands
[i
];
937 /* Step 6: Begin new chains for writes inside operands. */
938 /* ??? Many targets have output constraints on the SET_DEST
939 of a call insn, which is stupid, since these are certainly
940 ABI defined hard registers. Don't change calls at all.
941 Similarly take special care for asm statement that originally
942 referenced hard registers. */
943 if (asm_noperands (PATTERN (insn
)) > 0)
945 for (i
= 0; i
< n_ops
; i
++)
946 if (recog_data
.operand_type
[i
] == OP_OUT
)
948 rtx
*loc
= recog_data
.operand_loc
[i
];
950 enum reg_class
class = recog_op_alt
[i
][alt
].class;
952 if (GET_CODE (op
) == REG
953 && REGNO (op
) == ORIGINAL_REGNO (op
))
956 scan_rtx (insn
, loc
, class, mark_write
, OP_OUT
,
957 recog_op_alt
[i
][alt
].earlyclobber
);
960 else if (GET_CODE (insn
) != CALL_INSN
)
961 for (i
= 0; i
< n_ops
+ recog_data
.n_dups
; i
++)
963 int opn
= i
< n_ops
? i
: recog_data
.dup_num
[i
- n_ops
];
964 rtx
*loc
= (i
< n_ops
965 ? recog_data
.operand_loc
[opn
]
966 : recog_data
.dup_loc
[i
- n_ops
]);
967 enum reg_class
class = recog_op_alt
[opn
][alt
].class;
969 if (recog_data
.operand_type
[opn
] == OP_OUT
)
970 scan_rtx (insn
, loc
, class, mark_write
, OP_OUT
,
971 recog_op_alt
[opn
][alt
].earlyclobber
);
974 /* Step 7: Close chains for registers that were never
976 for (note
= REG_NOTES (insn
); note
; note
= XEXP (note
, 1))
977 if (REG_NOTE_KIND (note
) == REG_UNUSED
)
978 scan_rtx (insn
, &XEXP (note
, 0), NO_REGS
, terminate_dead
,
985 /* Since we close every chain when we find a REG_DEAD note, anything that
986 is still open lives past the basic block, so it can't be renamed. */
987 return closed_chains
;
990 /* Dump all def/use chains in CHAINS to RTL_DUMP_FILE. They are
991 printed in reverse order as that's how we build them. */
994 dump_def_use_chain (chains
)
995 struct du_chain
*chains
;
999 struct du_chain
*this = chains
;
1000 int r
= REGNO (*this->loc
);
1001 int nregs
= HARD_REGNO_NREGS (r
, GET_MODE (*this->loc
));
1002 fprintf (rtl_dump_file
, "Register %s (%d):", reg_names
[r
], nregs
);
1005 fprintf (rtl_dump_file
, " %d [%s]", INSN_UID (this->insn
),
1006 reg_class_names
[this->class]);
1007 this = this->next_use
;
1009 fprintf (rtl_dump_file
, "\n");
1010 chains
= chains
->next_chain
;
1014 /* The following code does forward propagation of hard register copies.
1015 The object is to eliminate as many dependencies as possible, so that
1016 we have the most scheduling freedom. As a side effect, we also clean
1017 up some silly register allocation decisions made by reload. This
1018 code may be obsoleted by a new register allocator. */
1020 /* For each register, we have a list of registers that contain the same
1021 value. The OLDEST_REGNO field points to the head of the list, and
1022 the NEXT_REGNO field runs through the list. The MODE field indicates
1023 what mode the data is known to be in; this field is VOIDmode when the
1024 register is not known to contain valid data. */
1026 struct value_data_entry
1028 enum machine_mode mode
;
1029 unsigned int oldest_regno
;
1030 unsigned int next_regno
;
1035 struct value_data_entry e
[FIRST_PSEUDO_REGISTER
];
1036 unsigned int max_value_regs
;
1039 static void kill_value_regno
PARAMS ((unsigned, struct value_data
*));
1040 static void kill_value
PARAMS ((rtx
, struct value_data
*));
1041 static void set_value_regno
PARAMS ((unsigned, enum machine_mode
,
1042 struct value_data
*));
1043 static void init_value_data
PARAMS ((struct value_data
*));
1044 static void kill_clobbered_value
PARAMS ((rtx
, rtx
, void *));
1045 static void kill_set_value
PARAMS ((rtx
, rtx
, void *));
1046 static int kill_autoinc_value
PARAMS ((rtx
*, void *));
1047 static void copy_value
PARAMS ((rtx
, rtx
, struct value_data
*));
1048 static bool mode_change_ok
PARAMS ((enum machine_mode
, enum machine_mode
,
1050 static rtx maybe_mode_change
PARAMS ((enum machine_mode
, enum machine_mode
,
1051 enum machine_mode
, unsigned int,
1053 static rtx find_oldest_value_reg
PARAMS ((enum reg_class
, rtx
,
1054 struct value_data
*));
1055 static bool replace_oldest_value_reg
PARAMS ((rtx
*, enum reg_class
, rtx
,
1056 struct value_data
*));
1057 static bool replace_oldest_value_addr
PARAMS ((rtx
*, enum reg_class
,
1058 enum machine_mode
, rtx
,
1059 struct value_data
*));
1060 static bool replace_oldest_value_mem
PARAMS ((rtx
, rtx
, struct value_data
*));
1061 static bool copyprop_hardreg_forward_1
PARAMS ((basic_block
,
1062 struct value_data
*));
1063 extern void debug_value_data
PARAMS ((struct value_data
*));
1064 #ifdef ENABLE_CHECKING
1065 static void validate_value_data
PARAMS ((struct value_data
*));
1068 /* Kill register REGNO. This involves removing it from any value lists,
1069 and resetting the value mode to VOIDmode. */
1072 kill_value_regno (regno
, vd
)
1074 struct value_data
*vd
;
1076 unsigned int i
, next
;
1078 if (vd
->e
[regno
].oldest_regno
!= regno
)
1080 for (i
= vd
->e
[regno
].oldest_regno
;
1081 vd
->e
[i
].next_regno
!= regno
;
1082 i
= vd
->e
[i
].next_regno
)
1084 vd
->e
[i
].next_regno
= vd
->e
[regno
].next_regno
;
1086 else if ((next
= vd
->e
[regno
].next_regno
) != INVALID_REGNUM
)
1088 for (i
= next
; i
!= INVALID_REGNUM
; i
= vd
->e
[i
].next_regno
)
1089 vd
->e
[i
].oldest_regno
= next
;
1092 vd
->e
[regno
].mode
= VOIDmode
;
1093 vd
->e
[regno
].oldest_regno
= regno
;
1094 vd
->e
[regno
].next_regno
= INVALID_REGNUM
;
1096 #ifdef ENABLE_CHECKING
1097 validate_value_data (vd
);
1101 /* Kill X. This is a convenience function for kill_value_regno
1102 so that we mind the mode the register is in. */
1107 struct value_data
*vd
;
1109 /* SUBREGS are supposed to have been eliminated by now. But some
1110 ports, e.g. i386 sse, use them to smuggle vector type information
1111 through to instruction selection. Each such SUBREG should simplify,
1112 so if we get a NULL we've done something wrong elsewhere. */
1114 if (GET_CODE (x
) == SUBREG
)
1115 x
= simplify_subreg (GET_MODE (x
), SUBREG_REG (x
),
1116 GET_MODE (SUBREG_REG (x
)), SUBREG_BYTE (x
));
1119 unsigned int regno
= REGNO (x
);
1120 unsigned int n
= HARD_REGNO_NREGS (regno
, GET_MODE (x
));
1123 /* Kill the value we're told to kill. */
1124 for (i
= 0; i
< n
; ++i
)
1125 kill_value_regno (regno
+ i
, vd
);
1127 /* Kill everything that overlapped what we're told to kill. */
1128 if (regno
< vd
->max_value_regs
)
1131 j
= regno
- vd
->max_value_regs
;
1132 for (; j
< regno
; ++j
)
1134 if (vd
->e
[j
].mode
== VOIDmode
)
1136 n
= HARD_REGNO_NREGS (j
, vd
->e
[j
].mode
);
1138 for (i
= 0; i
< n
; ++i
)
1139 kill_value_regno (j
+ i
, vd
);
1144 /* Remember that REGNO is valid in MODE. */
1147 set_value_regno (regno
, mode
, vd
)
1149 enum machine_mode mode
;
1150 struct value_data
*vd
;
1154 vd
->e
[regno
].mode
= mode
;
1156 nregs
= HARD_REGNO_NREGS (regno
, mode
);
1157 if (nregs
> vd
->max_value_regs
)
1158 vd
->max_value_regs
= nregs
;
1161 /* Initialize VD such that there are no known relationships between regs. */
1164 init_value_data (vd
)
1165 struct value_data
*vd
;
1168 for (i
= 0; i
< FIRST_PSEUDO_REGISTER
; ++i
)
1170 vd
->e
[i
].mode
= VOIDmode
;
1171 vd
->e
[i
].oldest_regno
= i
;
1172 vd
->e
[i
].next_regno
= INVALID_REGNUM
;
1174 vd
->max_value_regs
= 0;
1177 /* Called through note_stores. If X is clobbered, kill its value. */
1180 kill_clobbered_value (x
, set
, data
)
1185 struct value_data
*vd
= data
;
1186 if (GET_CODE (set
) == CLOBBER
)
1190 /* Called through note_stores. If X is set, not clobbered, kill its
1191 current value and install it as the root of its own value list. */
1194 kill_set_value (x
, set
, data
)
1199 struct value_data
*vd
= data
;
1200 if (GET_CODE (set
) != CLOBBER
)
1204 set_value_regno (REGNO (x
), GET_MODE (x
), vd
);
1208 /* Called through for_each_rtx. Kill any register used as the base of an
1209 auto-increment expression, and install that register as the root of its
1213 kill_autoinc_value (px
, data
)
1218 struct value_data
*vd
= data
;
1220 if (GET_RTX_CLASS (GET_CODE (x
)) == 'a')
1224 set_value_regno (REGNO (x
), Pmode
, vd
);
1231 /* Assert that SRC has been copied to DEST. Adjust the data structures
1232 to reflect that SRC contains an older copy of the shared value. */
1235 copy_value (dest
, src
, vd
)
1238 struct value_data
*vd
;
1240 unsigned int dr
= REGNO (dest
);
1241 unsigned int sr
= REGNO (src
);
1242 unsigned int dn
, sn
;
1245 /* ??? At present, it's possible to see noop sets. It'd be nice if
1246 this were cleaned up beforehand... */
1250 /* Do not propagate copies to the stack pointer, as that can leave
1251 memory accesses with no scheduling dependency on the stack update. */
1252 if (dr
== STACK_POINTER_REGNUM
)
1255 /* Likewise with the frame pointer, if we're using one. */
1256 if (frame_pointer_needed
&& dr
== HARD_FRAME_POINTER_REGNUM
)
1259 /* If SRC and DEST overlap, don't record anything. */
1260 dn
= HARD_REGNO_NREGS (dr
, GET_MODE (dest
));
1261 sn
= HARD_REGNO_NREGS (sr
, GET_MODE (dest
));
1262 if ((dr
> sr
&& dr
< sr
+ sn
)
1263 || (sr
> dr
&& sr
< dr
+ dn
))
1266 /* If SRC had no assigned mode (i.e. we didn't know it was live)
1267 assign it now and assume the value came from an input argument
1269 if (vd
->e
[sr
].mode
== VOIDmode
)
1270 set_value_regno (sr
, vd
->e
[dr
].mode
, vd
);
1272 /* If we are narrowing the input to a smaller number of hard regs,
1273 and it is in big endian, we are really extracting a high part.
1274 Since we generally associate a low part of a value with the value itself,
1275 we must not do the same for the high part.
1276 Note we can still get low parts for the same mode combination through
1277 a two-step copy involving differently sized hard regs.
1278 Assume hard regs fr* are 32 bits bits each, while r* are 64 bits each:
1279 (set (reg:DI r0) (reg:DI fr0))
1280 (set (reg:SI fr2) (reg:SI r0))
1281 loads the low part of (reg:DI fr0) - i.e. fr1 - into fr2, while:
1282 (set (reg:SI fr2) (reg:SI fr0))
1283 loads the high part of (reg:DI fr0) into fr2.
1285 We can't properly represent the latter case in our tables, so don't
1286 record anything then. */
1287 else if (sn
< (unsigned int) HARD_REGNO_NREGS (sr
, vd
->e
[sr
].mode
)
1288 && (GET_MODE_SIZE (vd
->e
[sr
].mode
) > UNITS_PER_WORD
1289 ? WORDS_BIG_ENDIAN
: BYTES_BIG_ENDIAN
))
1292 /* If SRC had been assigned a mode narrower than the copy, we can't
1293 link DEST into the chain, because not all of the pieces of the
1294 copy came from oldest_regno. */
1295 else if (sn
> (unsigned int) HARD_REGNO_NREGS (sr
, vd
->e
[sr
].mode
))
1298 /* Link DR at the end of the value chain used by SR. */
1300 vd
->e
[dr
].oldest_regno
= vd
->e
[sr
].oldest_regno
;
1302 for (i
= sr
; vd
->e
[i
].next_regno
!= INVALID_REGNUM
; i
= vd
->e
[i
].next_regno
)
1304 vd
->e
[i
].next_regno
= dr
;
1306 #ifdef ENABLE_CHECKING
1307 validate_value_data (vd
);
1311 /* Return true if a mode change from ORIG to NEW is allowed for REGNO. */
1314 mode_change_ok (orig_mode
, new_mode
, regno
)
1315 enum machine_mode orig_mode
, new_mode
;
1316 unsigned int regno ATTRIBUTE_UNUSED
;
1318 if (GET_MODE_SIZE (orig_mode
) < GET_MODE_SIZE (new_mode
))
1321 #ifdef CANNOT_CHANGE_MODE_CLASS
1322 return !REG_CANNOT_CHANGE_MODE_P (regno
, orig_mode
, new_mode
);
1328 /* Register REGNO was originally set in ORIG_MODE. It - or a copy of it -
1329 was copied in COPY_MODE to COPY_REGNO, and then COPY_REGNO was accessed
1331 Return a NEW_MODE rtx for REGNO if that's OK, otherwise return NULL_RTX. */
1334 maybe_mode_change (orig_mode
, copy_mode
, new_mode
, regno
, copy_regno
)
1335 enum machine_mode orig_mode
, copy_mode
, new_mode
;
1336 unsigned int regno
, copy_regno ATTRIBUTE_UNUSED
;
1338 if (orig_mode
== new_mode
)
1339 return gen_rtx_raw_REG (new_mode
, regno
);
1340 else if (mode_change_ok (orig_mode
, new_mode
, regno
))
1342 int copy_nregs
= HARD_REGNO_NREGS (copy_regno
, copy_mode
);
1343 int use_nregs
= HARD_REGNO_NREGS (copy_regno
, new_mode
);
1345 = GET_MODE_SIZE (copy_mode
) / copy_nregs
* (copy_nregs
- use_nregs
);
1347 = GET_MODE_SIZE (orig_mode
) - GET_MODE_SIZE (new_mode
) - copy_offset
;
1348 int byteoffset
= offset
% UNITS_PER_WORD
;
1349 int wordoffset
= offset
- byteoffset
;
1351 offset
= ((WORDS_BIG_ENDIAN
? wordoffset
: 0)
1352 + (BYTES_BIG_ENDIAN
? byteoffset
: 0));
1353 return gen_rtx_raw_REG (new_mode
,
1354 regno
+ subreg_regno_offset (regno
, orig_mode
,
1361 /* Find the oldest copy of the value contained in REGNO that is in
1362 register class CLASS and has mode MODE. If found, return an rtx
1363 of that oldest register, otherwise return NULL. */
1366 find_oldest_value_reg (class, reg
, vd
)
1367 enum reg_class
class;
1369 struct value_data
*vd
;
1371 unsigned int regno
= REGNO (reg
);
1372 enum machine_mode mode
= GET_MODE (reg
);
1375 /* If we are accessing REG in some mode other that what we set it in,
1376 make sure that the replacement is valid. In particular, consider
1377 (set (reg:DI r11) (...))
1378 (set (reg:SI r9) (reg:SI r11))
1379 (set (reg:SI r10) (...))
1380 (set (...) (reg:DI r9))
1381 Replacing r9 with r11 is invalid. */
1382 if (mode
!= vd
->e
[regno
].mode
)
1384 if (HARD_REGNO_NREGS (regno
, mode
)
1385 > HARD_REGNO_NREGS (regno
, vd
->e
[regno
].mode
))
1389 for (i
= vd
->e
[regno
].oldest_regno
; i
!= regno
; i
= vd
->e
[i
].next_regno
)
1391 enum machine_mode oldmode
= vd
->e
[i
].mode
;
1394 if (TEST_HARD_REG_BIT (reg_class_contents
[class], i
)
1395 && (new = maybe_mode_change (oldmode
, vd
->e
[regno
].mode
, mode
, i
,
1398 ORIGINAL_REGNO (new) = ORIGINAL_REGNO (reg
);
1399 REG_ATTRS (new) = REG_ATTRS (reg
);
1407 /* If possible, replace the register at *LOC with the oldest register
1408 in register class CLASS. Return true if successfully replaced. */
1411 replace_oldest_value_reg (loc
, class, insn
, vd
)
1413 enum reg_class
class;
1415 struct value_data
*vd
;
1417 rtx
new = find_oldest_value_reg (class, *loc
, vd
);
1421 fprintf (rtl_dump_file
, "insn %u: replaced reg %u with %u\n",
1422 INSN_UID (insn
), REGNO (*loc
), REGNO (new));
1430 /* Similar to replace_oldest_value_reg, but *LOC contains an address.
1431 Adapted from find_reloads_address_1. CLASS is INDEX_REG_CLASS or
1432 BASE_REG_CLASS depending on how the register is being considered. */
1435 replace_oldest_value_addr (loc
, class, mode
, insn
, vd
)
1437 enum reg_class
class;
1438 enum machine_mode mode
;
1440 struct value_data
*vd
;
1443 RTX_CODE code
= GET_CODE (x
);
1446 bool changed
= false;
1452 rtx orig_op0
= XEXP (x
, 0);
1453 rtx orig_op1
= XEXP (x
, 1);
1454 RTX_CODE code0
= GET_CODE (orig_op0
);
1455 RTX_CODE code1
= GET_CODE (orig_op1
);
1461 if (GET_CODE (op0
) == SUBREG
)
1463 op0
= SUBREG_REG (op0
);
1464 code0
= GET_CODE (op0
);
1467 if (GET_CODE (op1
) == SUBREG
)
1469 op1
= SUBREG_REG (op1
);
1470 code1
= GET_CODE (op1
);
1473 if (code0
== MULT
|| code0
== SIGN_EXTEND
|| code0
== TRUNCATE
1474 || code0
== ZERO_EXTEND
|| code1
== MEM
)
1476 locI
= &XEXP (x
, 0);
1477 locB
= &XEXP (x
, 1);
1479 else if (code1
== MULT
|| code1
== SIGN_EXTEND
|| code1
== TRUNCATE
1480 || code1
== ZERO_EXTEND
|| code0
== MEM
)
1482 locI
= &XEXP (x
, 1);
1483 locB
= &XEXP (x
, 0);
1485 else if (code0
== CONST_INT
|| code0
== CONST
1486 || code0
== SYMBOL_REF
|| code0
== LABEL_REF
)
1487 locB
= &XEXP (x
, 1);
1488 else if (code1
== CONST_INT
|| code1
== CONST
1489 || code1
== SYMBOL_REF
|| code1
== LABEL_REF
)
1490 locB
= &XEXP (x
, 0);
1491 else if (code0
== REG
&& code1
== REG
)
1495 if (REG_OK_FOR_INDEX_P (op0
)
1496 && REG_MODE_OK_FOR_BASE_P (op1
, mode
))
1498 else if (REG_OK_FOR_INDEX_P (op1
)
1499 && REG_MODE_OK_FOR_BASE_P (op0
, mode
))
1501 else if (REG_MODE_OK_FOR_BASE_P (op1
, mode
))
1503 else if (REG_MODE_OK_FOR_BASE_P (op0
, mode
))
1505 else if (REG_OK_FOR_INDEX_P (op1
))
1510 locI
= &XEXP (x
, index_op
);
1511 locB
= &XEXP (x
, !index_op
);
1513 else if (code0
== REG
)
1515 locI
= &XEXP (x
, 0);
1516 locB
= &XEXP (x
, 1);
1518 else if (code1
== REG
)
1520 locI
= &XEXP (x
, 1);
1521 locB
= &XEXP (x
, 0);
1525 changed
|= replace_oldest_value_addr (locI
, INDEX_REG_CLASS
, mode
,
1528 changed
|= replace_oldest_value_addr (locB
,
1529 MODE_BASE_REG_CLASS (mode
),
1543 return replace_oldest_value_mem (x
, insn
, vd
);
1546 return replace_oldest_value_reg (loc
, class, insn
, vd
);
1552 fmt
= GET_RTX_FORMAT (code
);
1553 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
1556 changed
|= replace_oldest_value_addr (&XEXP (x
, i
), class, mode
,
1558 else if (fmt
[i
] == 'E')
1559 for (j
= XVECLEN (x
, i
) - 1; j
>= 0; j
--)
1560 changed
|= replace_oldest_value_addr (&XVECEXP (x
, i
, j
), class,
1567 /* Similar to replace_oldest_value_reg, but X contains a memory. */
1570 replace_oldest_value_mem (x
, insn
, vd
)
1573 struct value_data
*vd
;
1575 return replace_oldest_value_addr (&XEXP (x
, 0),
1576 MODE_BASE_REG_CLASS (GET_MODE (x
)),
1577 GET_MODE (x
), insn
, vd
);
1580 /* Perform the forward copy propagation on basic block BB. */
1583 copyprop_hardreg_forward_1 (bb
, vd
)
1585 struct value_data
*vd
;
1587 bool changed
= false;
1590 for (insn
= bb
->head
; ; insn
= NEXT_INSN (insn
))
1592 int n_ops
, i
, alt
, predicated
;
1596 if (! INSN_P (insn
))
1598 if (insn
== bb
->end
)
1604 set
= single_set (insn
);
1605 extract_insn (insn
);
1606 if (! constrain_operands (1))
1607 fatal_insn_not_found (insn
);
1608 preprocess_constraints ();
1609 alt
= which_alternative
;
1610 n_ops
= recog_data
.n_operands
;
1611 is_asm
= asm_noperands (PATTERN (insn
)) >= 0;
1613 /* Simplify the code below by rewriting things to reflect
1614 matching constraints. Also promote OP_OUT to OP_INOUT
1615 in predicated instructions. */
1617 predicated
= GET_CODE (PATTERN (insn
)) == COND_EXEC
;
1618 for (i
= 0; i
< n_ops
; ++i
)
1620 int matches
= recog_op_alt
[i
][alt
].matches
;
1622 recog_op_alt
[i
][alt
].class = recog_op_alt
[matches
][alt
].class;
1623 if (matches
>= 0 || recog_op_alt
[i
][alt
].matched
>= 0
1624 || (predicated
&& recog_data
.operand_type
[i
] == OP_OUT
))
1625 recog_data
.operand_type
[i
] = OP_INOUT
;
1628 /* For each earlyclobber operand, zap the value data. */
1629 for (i
= 0; i
< n_ops
; i
++)
1630 if (recog_op_alt
[i
][alt
].earlyclobber
)
1631 kill_value (recog_data
.operand
[i
], vd
);
1633 /* Within asms, a clobber cannot overlap inputs or outputs.
1634 I wouldn't think this were true for regular insns, but
1635 scan_rtx treats them like that... */
1636 note_stores (PATTERN (insn
), kill_clobbered_value
, vd
);
1638 /* Kill all auto-incremented values. */
1639 /* ??? REG_INC is useless, since stack pushes aren't done that way. */
1640 for_each_rtx (&PATTERN (insn
), kill_autoinc_value
, vd
);
1642 /* Kill all early-clobbered operands. */
1643 for (i
= 0; i
< n_ops
; i
++)
1644 if (recog_op_alt
[i
][alt
].earlyclobber
)
1645 kill_value (recog_data
.operand
[i
], vd
);
1647 /* Special-case plain move instructions, since we may well
1648 be able to do the move from a different register class. */
1649 if (set
&& REG_P (SET_SRC (set
)))
1651 rtx src
= SET_SRC (set
);
1652 unsigned int regno
= REGNO (src
);
1653 enum machine_mode mode
= GET_MODE (src
);
1657 /* If we are accessing SRC in some mode other that what we
1658 set it in, make sure that the replacement is valid. */
1659 if (mode
!= vd
->e
[regno
].mode
)
1661 if (HARD_REGNO_NREGS (regno
, mode
)
1662 > HARD_REGNO_NREGS (regno
, vd
->e
[regno
].mode
))
1663 goto no_move_special_case
;
1666 /* If the destination is also a register, try to find a source
1667 register in the same class. */
1668 if (REG_P (SET_DEST (set
)))
1670 new = find_oldest_value_reg (REGNO_REG_CLASS (regno
), src
, vd
);
1671 if (new && validate_change (insn
, &SET_SRC (set
), new, 0))
1674 fprintf (rtl_dump_file
,
1675 "insn %u: replaced reg %u with %u\n",
1676 INSN_UID (insn
), regno
, REGNO (new));
1678 goto did_replacement
;
1682 /* Otherwise, try all valid registers and see if its valid. */
1683 for (i
= vd
->e
[regno
].oldest_regno
; i
!= regno
;
1684 i
= vd
->e
[i
].next_regno
)
1686 new = maybe_mode_change (vd
->e
[i
].mode
, vd
->e
[regno
].mode
,
1688 if (new != NULL_RTX
)
1690 if (validate_change (insn
, &SET_SRC (set
), new, 0))
1692 ORIGINAL_REGNO (new) = ORIGINAL_REGNO (src
);
1693 REG_ATTRS (new) = REG_ATTRS (src
);
1695 fprintf (rtl_dump_file
,
1696 "insn %u: replaced reg %u with %u\n",
1697 INSN_UID (insn
), regno
, REGNO (new));
1699 goto did_replacement
;
1704 no_move_special_case
:
1706 /* For each input operand, replace a hard register with the
1707 eldest live copy that's in an appropriate register class. */
1708 for (i
= 0; i
< n_ops
; i
++)
1710 bool replaced
= false;
1712 /* Don't scan match_operand here, since we've no reg class
1713 information to pass down. Any operands that we could
1714 substitute in will be represented elsewhere. */
1715 if (recog_data
.constraints
[i
][0] == '\0')
1718 /* Don't replace in asms intentionally referencing hard regs. */
1719 if (is_asm
&& GET_CODE (recog_data
.operand
[i
]) == REG
1720 && (REGNO (recog_data
.operand
[i
])
1721 == ORIGINAL_REGNO (recog_data
.operand
[i
])))
1724 if (recog_data
.operand_type
[i
] == OP_IN
)
1726 if (recog_op_alt
[i
][alt
].is_address
)
1728 = replace_oldest_value_addr (recog_data
.operand_loc
[i
],
1729 recog_op_alt
[i
][alt
].class,
1730 VOIDmode
, insn
, vd
);
1731 else if (REG_P (recog_data
.operand
[i
]))
1733 = replace_oldest_value_reg (recog_data
.operand_loc
[i
],
1734 recog_op_alt
[i
][alt
].class,
1736 else if (GET_CODE (recog_data
.operand
[i
]) == MEM
)
1737 replaced
= replace_oldest_value_mem (recog_data
.operand
[i
],
1740 else if (GET_CODE (recog_data
.operand
[i
]) == MEM
)
1741 replaced
= replace_oldest_value_mem (recog_data
.operand
[i
],
1744 /* If we performed any replacement, update match_dups. */
1752 new = *recog_data
.operand_loc
[i
];
1753 recog_data
.operand
[i
] = new;
1754 for (j
= 0; j
< recog_data
.n_dups
; j
++)
1755 if (recog_data
.dup_num
[j
] == i
)
1756 *recog_data
.dup_loc
[j
] = new;
1761 /* Clobber call-clobbered registers. */
1762 if (GET_CODE (insn
) == CALL_INSN
)
1763 for (i
= 0; i
< FIRST_PSEUDO_REGISTER
; i
++)
1764 if (TEST_HARD_REG_BIT (regs_invalidated_by_call
, i
))
1765 kill_value_regno (i
, vd
);
1767 /* Notice stores. */
1768 note_stores (PATTERN (insn
), kill_set_value
, vd
);
1770 /* Notice copies. */
1771 if (set
&& REG_P (SET_DEST (set
)) && REG_P (SET_SRC (set
)))
1772 copy_value (SET_DEST (set
), SET_SRC (set
), vd
);
1774 if (insn
== bb
->end
)
1781 /* Main entry point for the forward copy propagation optimization. */
1784 copyprop_hardreg_forward ()
1786 struct value_data
*all_vd
;
1788 basic_block bb
, bbp
= 0;
1790 need_refresh
= false;
1792 all_vd
= xmalloc (sizeof (struct value_data
) * last_basic_block
);
1796 /* If a block has a single predecessor, that we've already
1797 processed, begin with the value data that was live at
1798 the end of the predecessor block. */
1799 /* ??? Ought to use more intelligent queueing of blocks. */
1801 for (bbp
= bb
; bbp
&& bbp
!= bb
->pred
->src
; bbp
= bbp
->prev_bb
);
1803 && ! bb
->pred
->pred_next
1804 && ! (bb
->pred
->flags
& (EDGE_ABNORMAL_CALL
| EDGE_EH
))
1805 && bb
->pred
->src
!= ENTRY_BLOCK_PTR
1807 all_vd
[bb
->index
] = all_vd
[bb
->pred
->src
->index
];
1809 init_value_data (all_vd
+ bb
->index
);
1811 if (copyprop_hardreg_forward_1 (bb
, all_vd
+ bb
->index
))
1812 need_refresh
= true;
1818 fputs ("\n\n", rtl_dump_file
);
1820 /* ??? Irritatingly, delete_noop_moves does not take a set of blocks
1821 to scan, so we have to do a life update with no initial set of
1822 blocks Just In Case. */
1823 delete_noop_moves (get_insns ());
1824 update_life_info (NULL
, UPDATE_LIFE_GLOBAL_RM_NOTES
,
1826 | PROP_SCAN_DEAD_CODE
1827 | PROP_KILL_DEAD_CODE
);
1833 /* Dump the value chain data to stderr. */
1836 debug_value_data (vd
)
1837 struct value_data
*vd
;
1842 CLEAR_HARD_REG_SET (set
);
1844 for (i
= 0; i
< FIRST_PSEUDO_REGISTER
; ++i
)
1845 if (vd
->e
[i
].oldest_regno
== i
)
1847 if (vd
->e
[i
].mode
== VOIDmode
)
1849 if (vd
->e
[i
].next_regno
!= INVALID_REGNUM
)
1850 fprintf (stderr
, "[%u] Bad next_regno for empty chain (%u)\n",
1851 i
, vd
->e
[i
].next_regno
);
1855 SET_HARD_REG_BIT (set
, i
);
1856 fprintf (stderr
, "[%u %s] ", i
, GET_MODE_NAME (vd
->e
[i
].mode
));
1858 for (j
= vd
->e
[i
].next_regno
;
1859 j
!= INVALID_REGNUM
;
1860 j
= vd
->e
[j
].next_regno
)
1862 if (TEST_HARD_REG_BIT (set
, j
))
1864 fprintf (stderr
, "[%u] Loop in regno chain\n", j
);
1868 if (vd
->e
[j
].oldest_regno
!= i
)
1870 fprintf (stderr
, "[%u] Bad oldest_regno (%u)\n",
1871 j
, vd
->e
[j
].oldest_regno
);
1874 SET_HARD_REG_BIT (set
, j
);
1875 fprintf (stderr
, "[%u %s] ", j
, GET_MODE_NAME (vd
->e
[j
].mode
));
1877 fputc ('\n', stderr
);
1880 for (i
= 0; i
< FIRST_PSEUDO_REGISTER
; ++i
)
1881 if (! TEST_HARD_REG_BIT (set
, i
)
1882 && (vd
->e
[i
].mode
!= VOIDmode
1883 || vd
->e
[i
].oldest_regno
!= i
1884 || vd
->e
[i
].next_regno
!= INVALID_REGNUM
))
1885 fprintf (stderr
, "[%u] Non-empty reg in chain (%s %u %i)\n",
1886 i
, GET_MODE_NAME (vd
->e
[i
].mode
), vd
->e
[i
].oldest_regno
,
1887 vd
->e
[i
].next_regno
);
1890 #ifdef ENABLE_CHECKING
1892 validate_value_data (vd
)
1893 struct value_data
*vd
;
1898 CLEAR_HARD_REG_SET (set
);
1900 for (i
= 0; i
< FIRST_PSEUDO_REGISTER
; ++i
)
1901 if (vd
->e
[i
].oldest_regno
== i
)
1903 if (vd
->e
[i
].mode
== VOIDmode
)
1905 if (vd
->e
[i
].next_regno
!= INVALID_REGNUM
)
1906 internal_error ("validate_value_data: [%u] Bad next_regno for empty chain (%u)",
1907 i
, vd
->e
[i
].next_regno
);
1911 SET_HARD_REG_BIT (set
, i
);
1913 for (j
= vd
->e
[i
].next_regno
;
1914 j
!= INVALID_REGNUM
;
1915 j
= vd
->e
[j
].next_regno
)
1917 if (TEST_HARD_REG_BIT (set
, j
))
1918 internal_error ("validate_value_data: Loop in regno chain (%u)",
1920 if (vd
->e
[j
].oldest_regno
!= i
)
1921 internal_error ("validate_value_data: [%u] Bad oldest_regno (%u)",
1922 j
, vd
->e
[j
].oldest_regno
);
1924 SET_HARD_REG_BIT (set
, j
);
1928 for (i
= 0; i
< FIRST_PSEUDO_REGISTER
; ++i
)
1929 if (! TEST_HARD_REG_BIT (set
, i
)
1930 && (vd
->e
[i
].mode
!= VOIDmode
1931 || vd
->e
[i
].oldest_regno
!= i
1932 || vd
->e
[i
].next_regno
!= INVALID_REGNUM
))
1933 internal_error ("validate_value_data: [%u] Non-empty reg in chain (%s %u %i)",
1934 i
, GET_MODE_NAME (vd
->e
[i
].mode
), vd
->e
[i
].oldest_regno
,
1935 vd
->e
[i
].next_regno
);