* configure.in: Arrange to include defaults.h in [ht]config.h/tm.h.
[official-gcc.git] / gcc / final.c
blob3a2fc1537c5e22356364a15767c356ef9b2f8ada
1 /* Convert RTL to assembler code and output it, for GNU compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
22 /* This is the final pass of the compiler.
23 It looks at the rtl code for a function and outputs assembler code.
25 Call `final_start_function' to output the assembler code for function entry,
26 `final' to output assembler code for some RTL code,
27 `final_end_function' to output assembler code for function exit.
28 If a function is compiled in several pieces, each piece is
29 output separately with `final'.
31 Some optimizations are also done at this level.
32 Move instructions that were made unnecessary by good register allocation
33 are detected and omitted from the output. (Though most of these
34 are removed by the last jump pass.)
36 Instructions to set the condition codes are omitted when it can be
37 seen that the condition codes already had the desired values.
39 In some cases it is sufficient if the inherited condition codes
40 have related values, but this may require the following insn
41 (the one that tests the condition codes) to be modified.
43 The code for the function prologue and epilogue are generated
44 directly as assembler code by the macros FUNCTION_PROLOGUE and
45 FUNCTION_EPILOGUE. Those instructions never exist as rtl. */
47 #include "config.h"
48 #include "system.h"
50 #include "tree.h"
51 #include "rtl.h"
52 #include "tm_p.h"
53 #include "regs.h"
54 #include "insn-config.h"
55 #include "insn-flags.h"
56 #include "insn-attr.h"
57 #include "insn-codes.h"
58 #include "recog.h"
59 #include "conditions.h"
60 #include "flags.h"
61 #include "real.h"
62 #include "hard-reg-set.h"
63 #include "output.h"
64 #include "except.h"
65 #include "function.h"
66 #include "toplev.h"
67 #include "reload.h"
68 #include "intl.h"
69 #include "basic-block.h"
71 /* Get N_SLINE and N_SOL from stab.h if we can expect the file to exist. */
72 #if defined (DBX_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
73 #include "dbxout.h"
74 #if defined (USG) || !defined (HAVE_STAB_H)
75 #include "gstab.h" /* If doing DBX on sysV, use our own stab.h. */
76 #else
77 #include <stab.h>
78 #endif
80 #endif /* DBX_DEBUGGING_INFO || XCOFF_DEBUGGING_INFO */
82 #ifndef ACCUMULATE_OUTGOING_ARGS
83 #define ACCUMULATE_OUTGOING_ARGS 0
84 #endif
86 #ifdef XCOFF_DEBUGGING_INFO
87 #include "xcoffout.h"
88 #endif
90 #ifdef DWARF_DEBUGGING_INFO
91 #include "dwarfout.h"
92 #endif
94 #if defined (DWARF2_UNWIND_INFO) || defined (DWARF2_DEBUGGING_INFO)
95 #include "dwarf2out.h"
96 #endif
98 #ifdef SDB_DEBUGGING_INFO
99 #include "sdbout.h"
100 #endif
102 /* .stabd code for line number. */
103 #ifndef N_SLINE
104 #define N_SLINE 0x44
105 #endif
107 /* .stabs code for included file name. */
108 #ifndef N_SOL
109 #define N_SOL 0x84
110 #endif
112 /* If we aren't using cc0, CC_STATUS_INIT shouldn't exist. So define a
113 null default for it to save conditionalization later. */
114 #ifndef CC_STATUS_INIT
115 #define CC_STATUS_INIT
116 #endif
118 /* How to start an assembler comment. */
119 #ifndef ASM_COMMENT_START
120 #define ASM_COMMENT_START ";#"
121 #endif
123 /* Is the given character a logical line separator for the assembler? */
124 #ifndef IS_ASM_LOGICAL_LINE_SEPARATOR
125 #define IS_ASM_LOGICAL_LINE_SEPARATOR(C) ((C) == ';')
126 #endif
128 #ifndef JUMP_TABLES_IN_TEXT_SECTION
129 #define JUMP_TABLES_IN_TEXT_SECTION 0
130 #endif
132 /* Last insn processed by final_scan_insn. */
133 static rtx debug_insn;
134 rtx current_output_insn;
136 /* Line number of last NOTE. */
137 static int last_linenum;
139 /* Highest line number in current block. */
140 static int high_block_linenum;
142 /* Likewise for function. */
143 static int high_function_linenum;
145 /* Filename of last NOTE. */
146 static const char *last_filename;
148 /* Number of basic blocks seen so far;
149 used if profile_block_flag is set. */
150 static int count_basic_blocks;
152 /* Number of instrumented arcs when profile_arc_flag is set. */
153 extern int count_instrumented_edges;
155 extern int length_unit_log; /* This is defined in insn-attrtab.c. */
157 /* Nonzero while outputting an `asm' with operands.
158 This means that inconsistencies are the user's fault, so don't abort.
159 The precise value is the insn being output, to pass to error_for_asm. */
160 static rtx this_is_asm_operands;
162 /* Number of operands of this insn, for an `asm' with operands. */
163 static unsigned int insn_noperands;
165 /* Compare optimization flag. */
167 static rtx last_ignored_compare = 0;
169 /* Flag indicating this insn is the start of a new basic block. */
171 static int new_block = 1;
173 /* Assign a unique number to each insn that is output.
174 This can be used to generate unique local labels. */
176 static int insn_counter = 0;
178 #ifdef HAVE_cc0
179 /* This variable contains machine-dependent flags (defined in tm.h)
180 set and examined by output routines
181 that describe how to interpret the condition codes properly. */
183 CC_STATUS cc_status;
185 /* During output of an insn, this contains a copy of cc_status
186 from before the insn. */
188 CC_STATUS cc_prev_status;
189 #endif
191 /* Indexed by hardware reg number, is 1 if that register is ever
192 used in the current function.
194 In life_analysis, or in stupid_life_analysis, this is set
195 up to record the hard regs used explicitly. Reload adds
196 in the hard regs used for holding pseudo regs. Final uses
197 it to generate the code in the function prologue and epilogue
198 to save and restore registers as needed. */
200 char regs_ever_live[FIRST_PSEUDO_REGISTER];
202 /* Nonzero means current function must be given a frame pointer.
203 Set in stmt.c if anything is allocated on the stack there.
204 Set in reload1.c if anything is allocated on the stack there. */
206 int frame_pointer_needed;
208 /* Assign unique numbers to labels generated for profiling. */
210 int profile_label_no;
212 /* Number of unmatched NOTE_INSN_BLOCK_BEG notes we have seen. */
214 static int block_depth;
216 /* Nonzero if have enabled APP processing of our assembler output. */
218 static int app_on;
220 /* If we are outputting an insn sequence, this contains the sequence rtx.
221 Zero otherwise. */
223 rtx final_sequence;
225 #ifdef ASSEMBLER_DIALECT
227 /* Number of the assembler dialect to use, starting at 0. */
228 static int dialect_number;
229 #endif
231 /* Indexed by line number, nonzero if there is a note for that line. */
233 static char *line_note_exists;
235 #ifdef HAVE_conditional_execution
236 /* Nonnull if the insn currently being emitted was a COND_EXEC pattern. */
237 rtx current_insn_predicate;
238 #endif
240 /* Linked list to hold line numbers for each basic block. */
242 struct bb_list
244 struct bb_list *next; /* pointer to next basic block */
245 int line_num; /* line number */
246 int file_label_num; /* LPBC<n> label # for stored filename */
247 int func_label_num; /* LPBC<n> label # for stored function name */
250 static struct bb_list *bb_head = 0; /* Head of basic block list */
251 static struct bb_list **bb_tail = &bb_head; /* Ptr to store next bb ptr */
252 static int bb_file_label_num = -1; /* Current label # for file */
253 static int bb_func_label_num = -1; /* Current label # for func */
255 /* Linked list to hold the strings for each file and function name output. */
257 struct bb_str
259 struct bb_str *next; /* pointer to next string */
260 const char *string; /* string */
261 int label_num; /* label number */
262 int length; /* string length */
265 static struct bb_str *sbb_head = 0; /* Head of string list. */
266 static struct bb_str **sbb_tail = &sbb_head; /* Ptr to store next bb str */
267 static int sbb_label_num = 0; /* Last label used */
269 #ifdef HAVE_ATTR_length
270 static int asm_insn_count PARAMS ((rtx));
271 #endif
272 static void profile_function PARAMS ((FILE *));
273 static void profile_after_prologue PARAMS ((FILE *));
274 static void add_bb PARAMS ((FILE *));
275 static int add_bb_string PARAMS ((const char *, int));
276 static void output_source_line PARAMS ((FILE *, rtx));
277 static rtx walk_alter_subreg PARAMS ((rtx));
278 static void output_asm_name PARAMS ((void));
279 static void output_operand PARAMS ((rtx, int));
280 #ifdef LEAF_REGISTERS
281 static void leaf_renumber_regs PARAMS ((rtx));
282 #endif
283 #ifdef HAVE_cc0
284 static int alter_cond PARAMS ((rtx));
285 #endif
286 #ifndef ADDR_VEC_ALIGN
287 static int final_addr_vec_align PARAMS ((rtx));
288 #endif
289 #ifdef HAVE_ATTR_length
290 static int align_fuzz PARAMS ((rtx, rtx, int, unsigned));
291 #endif
293 /* Initialize data in final at the beginning of a compilation. */
295 void
296 init_final (filename)
297 const char *filename ATTRIBUTE_UNUSED;
299 app_on = 0;
300 final_sequence = 0;
302 #ifdef ASSEMBLER_DIALECT
303 dialect_number = ASSEMBLER_DIALECT;
304 #endif
307 /* Called at end of source file,
308 to output the block-profiling table for this entire compilation. */
310 void
311 end_final (filename)
312 const char *filename;
314 int i;
316 if (profile_block_flag || profile_arc_flag)
318 char name[20];
319 int align = exact_log2 (BIGGEST_ALIGNMENT / BITS_PER_UNIT);
320 int size, rounded;
321 struct bb_list *ptr;
322 struct bb_str *sptr;
323 int long_bytes = LONG_TYPE_SIZE / BITS_PER_UNIT;
324 int pointer_bytes = POINTER_SIZE / BITS_PER_UNIT;
326 if (profile_block_flag)
327 size = long_bytes * count_basic_blocks;
328 else
329 size = long_bytes * count_instrumented_edges;
330 rounded = size;
332 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
333 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
334 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
336 data_section ();
338 /* Output the main header, of 11 words:
339 0: 1 if this file is initialized, else 0.
340 1: address of file name (LPBX1).
341 2: address of table of counts (LPBX2).
342 3: number of counts in the table.
343 4: always 0, for compatibility with Sun.
345 The following are GNU extensions:
347 5: address of table of start addrs of basic blocks (LPBX3).
348 6: Number of bytes in this header.
349 7: address of table of function names (LPBX4).
350 8: address of table of line numbers (LPBX5) or 0.
351 9: address of table of file names (LPBX6) or 0.
352 10: space reserved for basic block profiling. */
354 ASM_OUTPUT_ALIGN (asm_out_file, align);
356 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 0);
357 /* zero word */
358 assemble_integer (const0_rtx, long_bytes, 1);
360 /* address of filename */
361 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 1);
362 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name), pointer_bytes, 1);
364 /* address of count table */
365 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 2);
366 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name), pointer_bytes, 1);
368 /* count of the # of basic blocks or # of instrumented arcs */
369 if (profile_block_flag)
370 assemble_integer (GEN_INT (count_basic_blocks), long_bytes, 1);
371 else
372 assemble_integer (GEN_INT (count_instrumented_edges), long_bytes, 1);
374 /* zero word (link field) */
375 assemble_integer (const0_rtx, pointer_bytes, 1);
377 /* address of basic block start address table */
378 if (profile_block_flag)
380 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 3);
381 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name), pointer_bytes,
384 else
385 assemble_integer (const0_rtx, pointer_bytes, 1);
387 /* byte count for extended structure. */
388 assemble_integer (GEN_INT (11 * UNITS_PER_WORD), long_bytes, 1);
390 /* address of function name table */
391 if (profile_block_flag)
393 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 4);
394 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name), pointer_bytes,
397 else
398 assemble_integer (const0_rtx, pointer_bytes, 1);
400 /* address of line number and filename tables if debugging. */
401 if (write_symbols != NO_DEBUG && profile_block_flag)
403 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 5);
404 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name),
405 pointer_bytes, 1);
406 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 6);
407 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name),
408 pointer_bytes, 1);
410 else
412 assemble_integer (const0_rtx, pointer_bytes, 1);
413 assemble_integer (const0_rtx, pointer_bytes, 1);
416 /* space for extension ptr (link field) */
417 assemble_integer (const0_rtx, UNITS_PER_WORD, 1);
419 /* Output the file name changing the suffix to .d for Sun tcov
420 compatibility. */
421 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 1);
423 char *cwd = getpwd ();
424 int len = strlen (filename) + strlen (cwd) + 1;
425 char *data_file = (char *) alloca (len + 4);
427 strcpy (data_file, cwd);
428 strcat (data_file, "/");
429 strcat (data_file, filename);
430 strip_off_ending (data_file, len);
431 if (profile_block_flag)
432 strcat (data_file, ".d");
433 else
434 strcat (data_file, ".da");
435 assemble_string (data_file, strlen (data_file) + 1);
438 /* Make space for the table of counts. */
439 if (size == 0)
441 /* Realign data section. */
442 ASM_OUTPUT_ALIGN (asm_out_file, align);
443 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 2);
444 if (size != 0)
445 assemble_zeros (size);
447 else
449 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 2);
450 #ifdef ASM_OUTPUT_SHARED_LOCAL
451 if (flag_shared_data)
452 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
453 else
454 #endif
455 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
456 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name,
457 size, BIGGEST_ALIGNMENT);
458 #else
459 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
460 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size,
461 BIGGEST_ALIGNMENT);
462 #else
463 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
464 #endif
465 #endif
468 /* Output any basic block strings */
469 if (profile_block_flag)
471 readonly_data_section ();
472 if (sbb_head)
474 ASM_OUTPUT_ALIGN (asm_out_file, align);
475 for (sptr = sbb_head; sptr != 0; sptr = sptr->next)
477 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBC",
478 sptr->label_num);
479 assemble_string (sptr->string, sptr->length);
484 /* Output the table of addresses. */
485 if (profile_block_flag)
487 /* Realign in new section */
488 ASM_OUTPUT_ALIGN (asm_out_file, align);
489 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 3);
490 for (i = 0; i < count_basic_blocks; i++)
492 ASM_GENERATE_INTERNAL_LABEL (name, "LPB", i);
493 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name),
494 pointer_bytes, 1);
498 /* Output the table of function names. */
499 if (profile_block_flag)
501 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 4);
502 for ((ptr = bb_head), (i = 0); ptr != 0; (ptr = ptr->next), i++)
504 if (ptr->func_label_num >= 0)
506 ASM_GENERATE_INTERNAL_LABEL (name, "LPBC",
507 ptr->func_label_num);
508 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name),
509 pointer_bytes, 1);
511 else
512 assemble_integer (const0_rtx, pointer_bytes, 1);
515 for (; i < count_basic_blocks; i++)
516 assemble_integer (const0_rtx, pointer_bytes, 1);
519 if (write_symbols != NO_DEBUG && profile_block_flag)
521 /* Output the table of line numbers. */
522 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 5);
523 for ((ptr = bb_head), (i = 0); ptr != 0; (ptr = ptr->next), i++)
524 assemble_integer (GEN_INT (ptr->line_num), long_bytes, 1);
526 for (; i < count_basic_blocks; i++)
527 assemble_integer (const0_rtx, long_bytes, 1);
529 /* Output the table of file names. */
530 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 6);
531 for ((ptr = bb_head), (i = 0); ptr != 0; (ptr = ptr->next), i++)
533 if (ptr->file_label_num >= 0)
535 ASM_GENERATE_INTERNAL_LABEL (name, "LPBC",
536 ptr->file_label_num);
537 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name),
538 pointer_bytes, 1);
540 else
541 assemble_integer (const0_rtx, pointer_bytes, 1);
544 for (; i < count_basic_blocks; i++)
545 assemble_integer (const0_rtx, pointer_bytes, 1);
548 /* End with the address of the table of addresses,
549 so we can find it easily, as the last word in the file's text. */
550 if (profile_block_flag)
552 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 3);
553 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name), pointer_bytes,
559 /* Enable APP processing of subsequent output.
560 Used before the output from an `asm' statement. */
562 void
563 app_enable ()
565 if (! app_on)
567 fputs (ASM_APP_ON, asm_out_file);
568 app_on = 1;
572 /* Disable APP processing of subsequent output.
573 Called from varasm.c before most kinds of output. */
575 void
576 app_disable ()
578 if (app_on)
580 fputs (ASM_APP_OFF, asm_out_file);
581 app_on = 0;
585 /* Return the number of slots filled in the current
586 delayed branch sequence (we don't count the insn needing the
587 delay slot). Zero if not in a delayed branch sequence. */
589 #ifdef DELAY_SLOTS
591 dbr_sequence_length ()
593 if (final_sequence != 0)
594 return XVECLEN (final_sequence, 0) - 1;
595 else
596 return 0;
598 #endif
600 /* The next two pages contain routines used to compute the length of an insn
601 and to shorten branches. */
603 /* Arrays for insn lengths, and addresses. The latter is referenced by
604 `insn_current_length'. */
606 static short *insn_lengths;
608 #ifdef HAVE_ATTR_length
609 varray_type insn_addresses_;
610 #endif
612 /* Max uid for which the above arrays are valid. */
613 static int insn_lengths_max_uid;
615 /* Address of insn being processed. Used by `insn_current_length'. */
616 int insn_current_address;
618 /* Address of insn being processed in previous iteration. */
619 int insn_last_address;
621 /* konwn invariant alignment of insn being processed. */
622 int insn_current_align;
624 /* After shorten_branches, for any insn, uid_align[INSN_UID (insn)]
625 gives the next following alignment insn that increases the known
626 alignment, or NULL_RTX if there is no such insn.
627 For any alignment obtained this way, we can again index uid_align with
628 its uid to obtain the next following align that in turn increases the
629 alignment, till we reach NULL_RTX; the sequence obtained this way
630 for each insn we'll call the alignment chain of this insn in the following
631 comments. */
633 struct label_alignment
635 short alignment;
636 short max_skip;
639 static rtx *uid_align;
640 static int *uid_shuid;
641 static struct label_alignment *label_align;
643 /* Indicate that branch shortening hasn't yet been done. */
645 void
646 init_insn_lengths ()
648 if (label_align)
650 free (label_align);
651 label_align = 0;
653 if (uid_shuid)
655 free (uid_shuid);
656 uid_shuid = 0;
658 if (insn_lengths)
660 free (insn_lengths);
661 insn_lengths = 0;
662 insn_lengths_max_uid = 0;
664 #ifdef HAVE_ATTR_length
665 INSN_ADDRESSES_FREE ();
666 #endif
667 if (uid_align)
669 free (uid_align);
670 uid_align = 0;
674 /* Obtain the current length of an insn. If branch shortening has been done,
675 get its actual length. Otherwise, get its maximum length. */
678 get_attr_length (insn)
679 rtx insn ATTRIBUTE_UNUSED;
681 #ifdef HAVE_ATTR_length
682 rtx body;
683 int i;
684 int length = 0;
686 if (insn_lengths_max_uid > INSN_UID (insn))
687 return insn_lengths[INSN_UID (insn)];
688 else
689 switch (GET_CODE (insn))
691 case NOTE:
692 case BARRIER:
693 case CODE_LABEL:
694 return 0;
696 case CALL_INSN:
697 length = insn_default_length (insn);
698 break;
700 case JUMP_INSN:
701 body = PATTERN (insn);
702 if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
704 /* Alignment is machine-dependent and should be handled by
705 ADDR_VEC_ALIGN. */
707 else
708 length = insn_default_length (insn);
709 break;
711 case INSN:
712 body = PATTERN (insn);
713 if (GET_CODE (body) == USE || GET_CODE (body) == CLOBBER)
714 return 0;
716 else if (GET_CODE (body) == ASM_INPUT || asm_noperands (body) >= 0)
717 length = asm_insn_count (body) * insn_default_length (insn);
718 else if (GET_CODE (body) == SEQUENCE)
719 for (i = 0; i < XVECLEN (body, 0); i++)
720 length += get_attr_length (XVECEXP (body, 0, i));
721 else
722 length = insn_default_length (insn);
723 break;
725 default:
726 break;
729 #ifdef ADJUST_INSN_LENGTH
730 ADJUST_INSN_LENGTH (insn, length);
731 #endif
732 return length;
733 #else /* not HAVE_ATTR_length */
734 return 0;
735 #endif /* not HAVE_ATTR_length */
738 /* Code to handle alignment inside shorten_branches. */
740 /* Here is an explanation how the algorithm in align_fuzz can give
741 proper results:
743 Call a sequence of instructions beginning with alignment point X
744 and continuing until the next alignment point `block X'. When `X'
745 is used in an expression, it means the alignment value of the
746 alignment point.
748 Call the distance between the start of the first insn of block X, and
749 the end of the last insn of block X `IX', for the `inner size of X'.
750 This is clearly the sum of the instruction lengths.
752 Likewise with the next alignment-delimited block following X, which we
753 shall call block Y.
755 Call the distance between the start of the first insn of block X, and
756 the start of the first insn of block Y `OX', for the `outer size of X'.
758 The estimated padding is then OX - IX.
760 OX can be safely estimated as
762 if (X >= Y)
763 OX = round_up(IX, Y)
764 else
765 OX = round_up(IX, X) + Y - X
767 Clearly est(IX) >= real(IX), because that only depends on the
768 instruction lengths, and those being overestimated is a given.
770 Clearly round_up(foo, Z) >= round_up(bar, Z) if foo >= bar, so
771 we needn't worry about that when thinking about OX.
773 When X >= Y, the alignment provided by Y adds no uncertainty factor
774 for branch ranges starting before X, so we can just round what we have.
775 But when X < Y, we don't know anything about the, so to speak,
776 `middle bits', so we have to assume the worst when aligning up from an
777 address mod X to one mod Y, which is Y - X. */
779 #ifndef LABEL_ALIGN
780 #define LABEL_ALIGN(LABEL) align_labels_log
781 #endif
783 #ifndef LABEL_ALIGN_MAX_SKIP
784 #define LABEL_ALIGN_MAX_SKIP (align_labels-1)
785 #endif
787 #ifndef LOOP_ALIGN
788 #define LOOP_ALIGN(LABEL) align_loops_log
789 #endif
791 #ifndef LOOP_ALIGN_MAX_SKIP
792 #define LOOP_ALIGN_MAX_SKIP (align_loops-1)
793 #endif
795 #ifndef LABEL_ALIGN_AFTER_BARRIER
796 #define LABEL_ALIGN_AFTER_BARRIER(LABEL) align_jumps_log
797 #endif
799 #ifndef LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP
800 #define LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP (align_jumps-1)
801 #endif
803 #ifndef ADDR_VEC_ALIGN
804 static int
805 final_addr_vec_align (addr_vec)
806 rtx addr_vec;
808 int align = GET_MODE_SIZE (GET_MODE (PATTERN (addr_vec)));
810 if (align > BIGGEST_ALIGNMENT / BITS_PER_UNIT)
811 align = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
812 return exact_log2 (align);
816 #define ADDR_VEC_ALIGN(ADDR_VEC) final_addr_vec_align (ADDR_VEC)
817 #endif
819 #ifndef INSN_LENGTH_ALIGNMENT
820 #define INSN_LENGTH_ALIGNMENT(INSN) length_unit_log
821 #endif
823 #define INSN_SHUID(INSN) (uid_shuid[INSN_UID (INSN)])
825 static int min_labelno, max_labelno;
827 #define LABEL_TO_ALIGNMENT(LABEL) \
828 (label_align[CODE_LABEL_NUMBER (LABEL) - min_labelno].alignment)
830 #define LABEL_TO_MAX_SKIP(LABEL) \
831 (label_align[CODE_LABEL_NUMBER (LABEL) - min_labelno].max_skip)
833 /* For the benefit of port specific code do this also as a function. */
836 label_to_alignment (label)
837 rtx label;
839 return LABEL_TO_ALIGNMENT (label);
842 #ifdef HAVE_ATTR_length
843 /* The differences in addresses
844 between a branch and its target might grow or shrink depending on
845 the alignment the start insn of the range (the branch for a forward
846 branch or the label for a backward branch) starts out on; if these
847 differences are used naively, they can even oscillate infinitely.
848 We therefore want to compute a 'worst case' address difference that
849 is independent of the alignment the start insn of the range end
850 up on, and that is at least as large as the actual difference.
851 The function align_fuzz calculates the amount we have to add to the
852 naively computed difference, by traversing the part of the alignment
853 chain of the start insn of the range that is in front of the end insn
854 of the range, and considering for each alignment the maximum amount
855 that it might contribute to a size increase.
857 For casesi tables, we also want to know worst case minimum amounts of
858 address difference, in case a machine description wants to introduce
859 some common offset that is added to all offsets in a table.
860 For this purpose, align_fuzz with a growth argument of 0 comuptes the
861 appropriate adjustment. */
863 /* Compute the maximum delta by which the difference of the addresses of
864 START and END might grow / shrink due to a different address for start
865 which changes the size of alignment insns between START and END.
866 KNOWN_ALIGN_LOG is the alignment known for START.
867 GROWTH should be ~0 if the objective is to compute potential code size
868 increase, and 0 if the objective is to compute potential shrink.
869 The return value is undefined for any other value of GROWTH. */
871 static int
872 align_fuzz (start, end, known_align_log, growth)
873 rtx start, end;
874 int known_align_log;
875 unsigned growth;
877 int uid = INSN_UID (start);
878 rtx align_label;
879 int known_align = 1 << known_align_log;
880 int end_shuid = INSN_SHUID (end);
881 int fuzz = 0;
883 for (align_label = uid_align[uid]; align_label; align_label = uid_align[uid])
885 int align_addr, new_align;
887 uid = INSN_UID (align_label);
888 align_addr = INSN_ADDRESSES (uid) - insn_lengths[uid];
889 if (uid_shuid[uid] > end_shuid)
890 break;
891 known_align_log = LABEL_TO_ALIGNMENT (align_label);
892 new_align = 1 << known_align_log;
893 if (new_align < known_align)
894 continue;
895 fuzz += (-align_addr ^ growth) & (new_align - known_align);
896 known_align = new_align;
898 return fuzz;
901 /* Compute a worst-case reference address of a branch so that it
902 can be safely used in the presence of aligned labels. Since the
903 size of the branch itself is unknown, the size of the branch is
904 not included in the range. I.e. for a forward branch, the reference
905 address is the end address of the branch as known from the previous
906 branch shortening pass, minus a value to account for possible size
907 increase due to alignment. For a backward branch, it is the start
908 address of the branch as known from the current pass, plus a value
909 to account for possible size increase due to alignment.
910 NB.: Therefore, the maximum offset allowed for backward branches needs
911 to exclude the branch size. */
914 insn_current_reference_address (branch)
915 rtx branch;
917 rtx dest, seq;
918 int seq_uid;
920 if (! INSN_ADDRESSES_SET_P ())
921 return 0;
923 seq = NEXT_INSN (PREV_INSN (branch));
924 seq_uid = INSN_UID (seq);
925 if (GET_CODE (branch) != JUMP_INSN)
926 /* This can happen for example on the PA; the objective is to know the
927 offset to address something in front of the start of the function.
928 Thus, we can treat it like a backward branch.
929 We assume here that FUNCTION_BOUNDARY / BITS_PER_UNIT is larger than
930 any alignment we'd encounter, so we skip the call to align_fuzz. */
931 return insn_current_address;
932 dest = JUMP_LABEL (branch);
934 /* BRANCH has no proper alignment chain set, so use SEQ.
935 BRANCH also has no INSN_SHUID. */
936 if (INSN_SHUID (seq) < INSN_SHUID (dest))
938 /* Forward branch. */
939 return (insn_last_address + insn_lengths[seq_uid]
940 - align_fuzz (seq, dest, length_unit_log, ~0));
942 else
944 /* Backward branch. */
945 return (insn_current_address
946 + align_fuzz (dest, seq, length_unit_log, ~0));
949 #endif /* HAVE_ATTR_length */
951 /* Make a pass over all insns and compute their actual lengths by shortening
952 any branches of variable length if possible. */
954 /* Give a default value for the lowest address in a function. */
956 #ifndef FIRST_INSN_ADDRESS
957 #define FIRST_INSN_ADDRESS 0
958 #endif
960 /* shorten_branches might be called multiple times: for example, the SH
961 port splits out-of-range conditional branches in MACHINE_DEPENDENT_REORG.
962 In order to do this, it needs proper length information, which it obtains
963 by calling shorten_branches. This cannot be collapsed with
964 shorten_branches itself into a single pass unless we also want to intergate
965 reorg.c, since the branch splitting exposes new instructions with delay
966 slots. */
968 void
969 shorten_branches (first)
970 rtx first ATTRIBUTE_UNUSED;
972 rtx insn;
973 int max_uid;
974 int i;
975 int max_log;
976 int max_skip;
977 #ifdef HAVE_ATTR_length
978 #define MAX_CODE_ALIGN 16
979 rtx seq;
980 int something_changed = 1;
981 char *varying_length;
982 rtx body;
983 int uid;
984 rtx align_tab[MAX_CODE_ALIGN];
986 /* In order to make sure that all instructions have valid length info,
987 we must split them before we compute the address/length info. */
989 for (insn = NEXT_INSN (first); insn; insn = NEXT_INSN (insn))
990 if (INSN_P (insn))
992 rtx old = insn;
993 /* Don't split the insn if it has been deleted. */
994 if (! INSN_DELETED_P (old))
995 insn = try_split (PATTERN (old), old, 1);
996 /* When not optimizing, the old insn will be still left around
997 with only the 'deleted' bit set. Transform it into a note
998 to avoid confusion of subsequent processing. */
999 if (INSN_DELETED_P (old))
1001 PUT_CODE (old, NOTE);
1002 NOTE_LINE_NUMBER (old) = NOTE_INSN_DELETED;
1003 NOTE_SOURCE_FILE (old) = 0;
1006 #endif
1008 /* We must do some computations even when not actually shortening, in
1009 order to get the alignment information for the labels. */
1011 init_insn_lengths ();
1013 /* Compute maximum UID and allocate label_align / uid_shuid. */
1014 max_uid = get_max_uid ();
1016 max_labelno = max_label_num ();
1017 min_labelno = get_first_label_num ();
1018 label_align = (struct label_alignment *)
1019 xcalloc ((max_labelno - min_labelno + 1), sizeof (struct label_alignment));
1021 uid_shuid = (int *) xmalloc (max_uid * sizeof *uid_shuid);
1023 /* Initialize label_align and set up uid_shuid to be strictly
1024 monotonically rising with insn order. */
1025 /* We use max_log here to keep track of the maximum alignment we want to
1026 impose on the next CODE_LABEL (or the current one if we are processing
1027 the CODE_LABEL itself). */
1029 max_log = 0;
1030 max_skip = 0;
1032 for (insn = get_insns (), i = 1; insn; insn = NEXT_INSN (insn))
1034 int log;
1036 INSN_SHUID (insn) = i++;
1037 if (INSN_P (insn))
1039 /* reorg might make the first insn of a loop being run once only,
1040 and delete the label in front of it. Then we want to apply
1041 the loop alignment to the new label created by reorg, which
1042 is separated by the former loop start insn from the
1043 NOTE_INSN_LOOP_BEG. */
1045 else if (GET_CODE (insn) == CODE_LABEL)
1047 rtx next;
1049 log = LABEL_ALIGN (insn);
1050 if (max_log < log)
1052 max_log = log;
1053 max_skip = LABEL_ALIGN_MAX_SKIP;
1055 next = NEXT_INSN (insn);
1056 /* ADDR_VECs only take room if read-only data goes into the text
1057 section. */
1058 if (JUMP_TABLES_IN_TEXT_SECTION
1059 #if !defined(READONLY_DATA_SECTION)
1060 || 1
1061 #endif
1063 if (next && GET_CODE (next) == JUMP_INSN)
1065 rtx nextbody = PATTERN (next);
1066 if (GET_CODE (nextbody) == ADDR_VEC
1067 || GET_CODE (nextbody) == ADDR_DIFF_VEC)
1069 log = ADDR_VEC_ALIGN (next);
1070 if (max_log < log)
1072 max_log = log;
1073 max_skip = LABEL_ALIGN_MAX_SKIP;
1077 LABEL_TO_ALIGNMENT (insn) = max_log;
1078 LABEL_TO_MAX_SKIP (insn) = max_skip;
1079 max_log = 0;
1080 max_skip = 0;
1082 else if (GET_CODE (insn) == BARRIER)
1084 rtx label;
1086 for (label = insn; label && ! INSN_P (label);
1087 label = NEXT_INSN (label))
1088 if (GET_CODE (label) == CODE_LABEL)
1090 log = LABEL_ALIGN_AFTER_BARRIER (insn);
1091 if (max_log < log)
1093 max_log = log;
1094 max_skip = LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP;
1096 break;
1099 /* Again, we allow NOTE_INSN_LOOP_BEG - INSN - CODE_LABEL
1100 sequences in order to handle reorg output efficiently. */
1101 else if (GET_CODE (insn) == NOTE
1102 && NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG)
1104 rtx label;
1105 int nest = 0;
1107 /* Search for the label that starts the loop.
1108 Don't skip past the end of the loop, since that could
1109 lead to putting an alignment where it does not belong.
1110 However, a label after a nested (non-)loop would be OK. */
1111 for (label = insn; label; label = NEXT_INSN (label))
1113 if (GET_CODE (label) == NOTE
1114 && NOTE_LINE_NUMBER (label) == NOTE_INSN_LOOP_BEG)
1115 nest++;
1116 else if (GET_CODE (label) == NOTE
1117 && NOTE_LINE_NUMBER (label) == NOTE_INSN_LOOP_END
1118 && --nest == 0)
1119 break;
1120 else if (GET_CODE (label) == CODE_LABEL)
1122 log = LOOP_ALIGN (label);
1123 if (max_log < log)
1125 max_log = log;
1126 max_skip = LOOP_ALIGN_MAX_SKIP;
1128 break;
1132 else
1133 continue;
1135 #ifdef HAVE_ATTR_length
1137 /* Allocate the rest of the arrays. */
1138 insn_lengths = (short *) xmalloc (max_uid * sizeof (short));
1139 insn_lengths_max_uid = max_uid;
1140 /* Syntax errors can lead to labels being outside of the main insn stream.
1141 Initialize insn_addresses, so that we get reproducible results. */
1142 INSN_ADDRESSES_ALLOC (max_uid);
1144 varying_length = (char *) xcalloc (max_uid, sizeof (char));
1146 /* Initialize uid_align. We scan instructions
1147 from end to start, and keep in align_tab[n] the last seen insn
1148 that does an alignment of at least n+1, i.e. the successor
1149 in the alignment chain for an insn that does / has a known
1150 alignment of n. */
1151 uid_align = (rtx *) xcalloc (max_uid, sizeof *uid_align);
1153 for (i = MAX_CODE_ALIGN; --i >= 0;)
1154 align_tab[i] = NULL_RTX;
1155 seq = get_last_insn ();
1156 for (; seq; seq = PREV_INSN (seq))
1158 int uid = INSN_UID (seq);
1159 int log;
1160 log = (GET_CODE (seq) == CODE_LABEL ? LABEL_TO_ALIGNMENT (seq) : 0);
1161 uid_align[uid] = align_tab[0];
1162 if (log)
1164 /* Found an alignment label. */
1165 uid_align[uid] = align_tab[log];
1166 for (i = log - 1; i >= 0; i--)
1167 align_tab[i] = seq;
1170 #ifdef CASE_VECTOR_SHORTEN_MODE
1171 if (optimize)
1173 /* Look for ADDR_DIFF_VECs, and initialize their minimum and maximum
1174 label fields. */
1176 int min_shuid = INSN_SHUID (get_insns ()) - 1;
1177 int max_shuid = INSN_SHUID (get_last_insn ()) + 1;
1178 int rel;
1180 for (insn = first; insn != 0; insn = NEXT_INSN (insn))
1182 rtx min_lab = NULL_RTX, max_lab = NULL_RTX, pat;
1183 int len, i, min, max, insn_shuid;
1184 int min_align;
1185 addr_diff_vec_flags flags;
1187 if (GET_CODE (insn) != JUMP_INSN
1188 || GET_CODE (PATTERN (insn)) != ADDR_DIFF_VEC)
1189 continue;
1190 pat = PATTERN (insn);
1191 len = XVECLEN (pat, 1);
1192 if (len <= 0)
1193 abort ();
1194 min_align = MAX_CODE_ALIGN;
1195 for (min = max_shuid, max = min_shuid, i = len - 1; i >= 0; i--)
1197 rtx lab = XEXP (XVECEXP (pat, 1, i), 0);
1198 int shuid = INSN_SHUID (lab);
1199 if (shuid < min)
1201 min = shuid;
1202 min_lab = lab;
1204 if (shuid > max)
1206 max = shuid;
1207 max_lab = lab;
1209 if (min_align > LABEL_TO_ALIGNMENT (lab))
1210 min_align = LABEL_TO_ALIGNMENT (lab);
1212 XEXP (pat, 2) = gen_rtx_LABEL_REF (VOIDmode, min_lab);
1213 XEXP (pat, 3) = gen_rtx_LABEL_REF (VOIDmode, max_lab);
1214 insn_shuid = INSN_SHUID (insn);
1215 rel = INSN_SHUID (XEXP (XEXP (pat, 0), 0));
1216 flags.min_align = min_align;
1217 flags.base_after_vec = rel > insn_shuid;
1218 flags.min_after_vec = min > insn_shuid;
1219 flags.max_after_vec = max > insn_shuid;
1220 flags.min_after_base = min > rel;
1221 flags.max_after_base = max > rel;
1222 ADDR_DIFF_VEC_FLAGS (pat) = flags;
1225 #endif /* CASE_VECTOR_SHORTEN_MODE */
1227 /* Compute initial lengths, addresses, and varying flags for each insn. */
1228 for (insn_current_address = FIRST_INSN_ADDRESS, insn = first;
1229 insn != 0;
1230 insn_current_address += insn_lengths[uid], insn = NEXT_INSN (insn))
1232 uid = INSN_UID (insn);
1234 insn_lengths[uid] = 0;
1236 if (GET_CODE (insn) == CODE_LABEL)
1238 int log = LABEL_TO_ALIGNMENT (insn);
1239 if (log)
1241 int align = 1 << log;
1242 int new_address = (insn_current_address + align - 1) & -align;
1243 insn_lengths[uid] = new_address - insn_current_address;
1247 INSN_ADDRESSES (uid) = insn_current_address;
1249 if (GET_CODE (insn) == NOTE || GET_CODE (insn) == BARRIER
1250 || GET_CODE (insn) == CODE_LABEL)
1251 continue;
1252 if (INSN_DELETED_P (insn))
1253 continue;
1255 body = PATTERN (insn);
1256 if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
1258 /* This only takes room if read-only data goes into the text
1259 section. */
1260 if (JUMP_TABLES_IN_TEXT_SECTION
1261 #if !defined(READONLY_DATA_SECTION)
1262 || 1
1263 #endif
1265 insn_lengths[uid] = (XVECLEN (body,
1266 GET_CODE (body) == ADDR_DIFF_VEC)
1267 * GET_MODE_SIZE (GET_MODE (body)));
1268 /* Alignment is handled by ADDR_VEC_ALIGN. */
1270 else if (GET_CODE (body) == ASM_INPUT || asm_noperands (body) >= 0)
1271 insn_lengths[uid] = asm_insn_count (body) * insn_default_length (insn);
1272 else if (GET_CODE (body) == SEQUENCE)
1274 int i;
1275 int const_delay_slots;
1276 #ifdef DELAY_SLOTS
1277 const_delay_slots = const_num_delay_slots (XVECEXP (body, 0, 0));
1278 #else
1279 const_delay_slots = 0;
1280 #endif
1281 /* Inside a delay slot sequence, we do not do any branch shortening
1282 if the shortening could change the number of delay slots
1283 of the branch. */
1284 for (i = 0; i < XVECLEN (body, 0); i++)
1286 rtx inner_insn = XVECEXP (body, 0, i);
1287 int inner_uid = INSN_UID (inner_insn);
1288 int inner_length;
1290 if (GET_CODE (body) == ASM_INPUT
1291 || asm_noperands (PATTERN (XVECEXP (body, 0, i))) >= 0)
1292 inner_length = (asm_insn_count (PATTERN (inner_insn))
1293 * insn_default_length (inner_insn));
1294 else
1295 inner_length = insn_default_length (inner_insn);
1297 insn_lengths[inner_uid] = inner_length;
1298 if (const_delay_slots)
1300 if ((varying_length[inner_uid]
1301 = insn_variable_length_p (inner_insn)) != 0)
1302 varying_length[uid] = 1;
1303 INSN_ADDRESSES (inner_uid) = (insn_current_address
1304 + insn_lengths[uid]);
1306 else
1307 varying_length[inner_uid] = 0;
1308 insn_lengths[uid] += inner_length;
1311 else if (GET_CODE (body) != USE && GET_CODE (body) != CLOBBER)
1313 insn_lengths[uid] = insn_default_length (insn);
1314 varying_length[uid] = insn_variable_length_p (insn);
1317 /* If needed, do any adjustment. */
1318 #ifdef ADJUST_INSN_LENGTH
1319 ADJUST_INSN_LENGTH (insn, insn_lengths[uid]);
1320 if (insn_lengths[uid] < 0)
1321 fatal_insn ("Negative insn length", insn);
1322 #endif
1325 /* Now loop over all the insns finding varying length insns. For each,
1326 get the current insn length. If it has changed, reflect the change.
1327 When nothing changes for a full pass, we are done. */
1329 while (something_changed)
1331 something_changed = 0;
1332 insn_current_align = MAX_CODE_ALIGN - 1;
1333 for (insn_current_address = FIRST_INSN_ADDRESS, insn = first;
1334 insn != 0;
1335 insn = NEXT_INSN (insn))
1337 int new_length;
1338 #ifdef ADJUST_INSN_LENGTH
1339 int tmp_length;
1340 #endif
1341 int length_align;
1343 uid = INSN_UID (insn);
1345 if (GET_CODE (insn) == CODE_LABEL)
1347 int log = LABEL_TO_ALIGNMENT (insn);
1348 if (log > insn_current_align)
1350 int align = 1 << log;
1351 int new_address= (insn_current_address + align - 1) & -align;
1352 insn_lengths[uid] = new_address - insn_current_address;
1353 insn_current_align = log;
1354 insn_current_address = new_address;
1356 else
1357 insn_lengths[uid] = 0;
1358 INSN_ADDRESSES (uid) = insn_current_address;
1359 continue;
1362 length_align = INSN_LENGTH_ALIGNMENT (insn);
1363 if (length_align < insn_current_align)
1364 insn_current_align = length_align;
1366 insn_last_address = INSN_ADDRESSES (uid);
1367 INSN_ADDRESSES (uid) = insn_current_address;
1369 #ifdef CASE_VECTOR_SHORTEN_MODE
1370 if (optimize && GET_CODE (insn) == JUMP_INSN
1371 && GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)
1373 rtx body = PATTERN (insn);
1374 int old_length = insn_lengths[uid];
1375 rtx rel_lab = XEXP (XEXP (body, 0), 0);
1376 rtx min_lab = XEXP (XEXP (body, 2), 0);
1377 rtx max_lab = XEXP (XEXP (body, 3), 0);
1378 addr_diff_vec_flags flags = ADDR_DIFF_VEC_FLAGS (body);
1379 int rel_addr = INSN_ADDRESSES (INSN_UID (rel_lab));
1380 int min_addr = INSN_ADDRESSES (INSN_UID (min_lab));
1381 int max_addr = INSN_ADDRESSES (INSN_UID (max_lab));
1382 rtx prev;
1383 int rel_align = 0;
1385 /* Try to find a known alignment for rel_lab. */
1386 for (prev = rel_lab;
1387 prev
1388 && ! insn_lengths[INSN_UID (prev)]
1389 && ! (varying_length[INSN_UID (prev)] & 1);
1390 prev = PREV_INSN (prev))
1391 if (varying_length[INSN_UID (prev)] & 2)
1393 rel_align = LABEL_TO_ALIGNMENT (prev);
1394 break;
1397 /* See the comment on addr_diff_vec_flags in rtl.h for the
1398 meaning of the flags values. base: REL_LAB vec: INSN */
1399 /* Anything after INSN has still addresses from the last
1400 pass; adjust these so that they reflect our current
1401 estimate for this pass. */
1402 if (flags.base_after_vec)
1403 rel_addr += insn_current_address - insn_last_address;
1404 if (flags.min_after_vec)
1405 min_addr += insn_current_address - insn_last_address;
1406 if (flags.max_after_vec)
1407 max_addr += insn_current_address - insn_last_address;
1408 /* We want to know the worst case, i.e. lowest possible value
1409 for the offset of MIN_LAB. If MIN_LAB is after REL_LAB,
1410 its offset is positive, and we have to be wary of code shrink;
1411 otherwise, it is negative, and we have to be vary of code
1412 size increase. */
1413 if (flags.min_after_base)
1415 /* If INSN is between REL_LAB and MIN_LAB, the size
1416 changes we are about to make can change the alignment
1417 within the observed offset, therefore we have to break
1418 it up into two parts that are independent. */
1419 if (! flags.base_after_vec && flags.min_after_vec)
1421 min_addr -= align_fuzz (rel_lab, insn, rel_align, 0);
1422 min_addr -= align_fuzz (insn, min_lab, 0, 0);
1424 else
1425 min_addr -= align_fuzz (rel_lab, min_lab, rel_align, 0);
1427 else
1429 if (flags.base_after_vec && ! flags.min_after_vec)
1431 min_addr -= align_fuzz (min_lab, insn, 0, ~0);
1432 min_addr -= align_fuzz (insn, rel_lab, 0, ~0);
1434 else
1435 min_addr -= align_fuzz (min_lab, rel_lab, 0, ~0);
1437 /* Likewise, determine the highest lowest possible value
1438 for the offset of MAX_LAB. */
1439 if (flags.max_after_base)
1441 if (! flags.base_after_vec && flags.max_after_vec)
1443 max_addr += align_fuzz (rel_lab, insn, rel_align, ~0);
1444 max_addr += align_fuzz (insn, max_lab, 0, ~0);
1446 else
1447 max_addr += align_fuzz (rel_lab, max_lab, rel_align, ~0);
1449 else
1451 if (flags.base_after_vec && ! flags.max_after_vec)
1453 max_addr += align_fuzz (max_lab, insn, 0, 0);
1454 max_addr += align_fuzz (insn, rel_lab, 0, 0);
1456 else
1457 max_addr += align_fuzz (max_lab, rel_lab, 0, 0);
1459 PUT_MODE (body, CASE_VECTOR_SHORTEN_MODE (min_addr - rel_addr,
1460 max_addr - rel_addr,
1461 body));
1462 if (JUMP_TABLES_IN_TEXT_SECTION
1463 #if !defined(READONLY_DATA_SECTION)
1464 || 1
1465 #endif
1468 insn_lengths[uid]
1469 = (XVECLEN (body, 1) * GET_MODE_SIZE (GET_MODE (body)));
1470 insn_current_address += insn_lengths[uid];
1471 if (insn_lengths[uid] != old_length)
1472 something_changed = 1;
1475 continue;
1477 #endif /* CASE_VECTOR_SHORTEN_MODE */
1479 if (! (varying_length[uid]))
1481 insn_current_address += insn_lengths[uid];
1482 continue;
1484 if (GET_CODE (insn) == INSN && GET_CODE (PATTERN (insn)) == SEQUENCE)
1486 int i;
1488 body = PATTERN (insn);
1489 new_length = 0;
1490 for (i = 0; i < XVECLEN (body, 0); i++)
1492 rtx inner_insn = XVECEXP (body, 0, i);
1493 int inner_uid = INSN_UID (inner_insn);
1494 int inner_length;
1496 INSN_ADDRESSES (inner_uid) = insn_current_address;
1498 /* insn_current_length returns 0 for insns with a
1499 non-varying length. */
1500 if (! varying_length[inner_uid])
1501 inner_length = insn_lengths[inner_uid];
1502 else
1503 inner_length = insn_current_length (inner_insn);
1505 if (inner_length != insn_lengths[inner_uid])
1507 insn_lengths[inner_uid] = inner_length;
1508 something_changed = 1;
1510 insn_current_address += insn_lengths[inner_uid];
1511 new_length += inner_length;
1514 else
1516 new_length = insn_current_length (insn);
1517 insn_current_address += new_length;
1520 #ifdef ADJUST_INSN_LENGTH
1521 /* If needed, do any adjustment. */
1522 tmp_length = new_length;
1523 ADJUST_INSN_LENGTH (insn, new_length);
1524 insn_current_address += (new_length - tmp_length);
1525 #endif
1527 if (new_length != insn_lengths[uid])
1529 insn_lengths[uid] = new_length;
1530 something_changed = 1;
1533 /* For a non-optimizing compile, do only a single pass. */
1534 if (!optimize)
1535 break;
1538 free (varying_length);
1540 #endif /* HAVE_ATTR_length */
1543 #ifdef HAVE_ATTR_length
1544 /* Given the body of an INSN known to be generated by an ASM statement, return
1545 the number of machine instructions likely to be generated for this insn.
1546 This is used to compute its length. */
1548 static int
1549 asm_insn_count (body)
1550 rtx body;
1552 const char *template;
1553 int count = 1;
1555 if (GET_CODE (body) == ASM_INPUT)
1556 template = XSTR (body, 0);
1557 else
1558 template = decode_asm_operands (body, NULL_PTR, NULL_PTR,
1559 NULL_PTR, NULL_PTR);
1561 for (; *template; template++)
1562 if (IS_ASM_LOGICAL_LINE_SEPARATOR (*template) || *template == '\n')
1563 count++;
1565 return count;
1567 #endif
1569 /* Output assembler code for the start of a function,
1570 and initialize some of the variables in this file
1571 for the new function. The label for the function and associated
1572 assembler pseudo-ops have already been output in `assemble_start_function'.
1574 FIRST is the first insn of the rtl for the function being compiled.
1575 FILE is the file to write assembler code to.
1576 OPTIMIZE is nonzero if we should eliminate redundant
1577 test and compare insns. */
1579 void
1580 final_start_function (first, file, optimize)
1581 rtx first;
1582 FILE *file;
1583 int optimize ATTRIBUTE_UNUSED;
1585 block_depth = 0;
1587 this_is_asm_operands = 0;
1589 #ifdef NON_SAVING_SETJMP
1590 /* A function that calls setjmp should save and restore all the
1591 call-saved registers on a system where longjmp clobbers them. */
1592 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
1594 int i;
1596 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
1597 if (!call_used_regs[i])
1598 regs_ever_live[i] = 1;
1600 #endif
1602 /* Initial line number is supposed to be output
1603 before the function's prologue and label
1604 so that the function's address will not appear to be
1605 in the last statement of the preceding function. */
1606 if (NOTE_LINE_NUMBER (first) != NOTE_INSN_DELETED)
1607 last_linenum = high_block_linenum = high_function_linenum
1608 = NOTE_LINE_NUMBER (first);
1610 #if defined (DWARF2_UNWIND_INFO) || defined (DWARF2_DEBUGGING_INFO)
1611 /* Output DWARF definition of the function. */
1612 if (dwarf2out_do_frame ())
1613 dwarf2out_begin_prologue ();
1614 else
1615 current_function_func_begin_label = 0;
1616 #endif
1618 /* For SDB and XCOFF, the function beginning must be marked between
1619 the function label and the prologue. We always need this, even when
1620 -g1 was used. Defer on MIPS systems so that parameter descriptions
1621 follow function entry. */
1622 #if defined(SDB_DEBUGGING_INFO) && !defined(MIPS_DEBUGGING_INFO)
1623 if (write_symbols == SDB_DEBUG)
1624 sdbout_begin_function (last_linenum);
1625 else
1626 #endif
1627 #ifdef XCOFF_DEBUGGING_INFO
1628 if (write_symbols == XCOFF_DEBUG)
1629 xcoffout_begin_function (file, last_linenum);
1630 else
1631 #endif
1632 /* But only output line number for other debug info types if -g2
1633 or better. */
1634 if (NOTE_LINE_NUMBER (first) != NOTE_INSN_DELETED)
1635 output_source_line (file, first);
1637 #ifdef LEAF_REG_REMAP
1638 if (current_function_uses_only_leaf_regs)
1639 leaf_renumber_regs (first);
1640 #endif
1642 /* The Sun386i and perhaps other machines don't work right
1643 if the profiling code comes after the prologue. */
1644 #ifdef PROFILE_BEFORE_PROLOGUE
1645 if (profile_flag)
1646 profile_function (file);
1647 #endif /* PROFILE_BEFORE_PROLOGUE */
1649 #if defined (DWARF2_UNWIND_INFO) && defined (HAVE_prologue)
1650 if (dwarf2out_do_frame ())
1651 dwarf2out_frame_debug (NULL_RTX);
1652 #endif
1654 /* If debugging, assign block numbers to all of the blocks in this
1655 function. */
1656 if (write_symbols)
1658 number_blocks (current_function_decl);
1659 remove_unnecessary_notes ();
1660 /* We never actually put out begin/end notes for the top-level
1661 block in the function. But, conceptually, that block is
1662 always needed. */
1663 TREE_ASM_WRITTEN (DECL_INITIAL (current_function_decl)) = 1;
1666 #ifdef FUNCTION_PROLOGUE
1667 /* First output the function prologue: code to set up the stack frame. */
1668 FUNCTION_PROLOGUE (file, get_frame_size ());
1669 #endif
1671 /* If the machine represents the prologue as RTL, the profiling code must
1672 be emitted when NOTE_INSN_PROLOGUE_END is scanned. */
1673 #ifdef HAVE_prologue
1674 if (! HAVE_prologue)
1675 #endif
1676 profile_after_prologue (file);
1678 profile_label_no++;
1680 /* If we are doing basic block profiling, remember a printable version
1681 of the function name. */
1682 if (profile_block_flag)
1684 bb_func_label_num =
1685 add_bb_string ((*decl_printable_name) (current_function_decl, 2),
1686 FALSE);
1690 static void
1691 profile_after_prologue (file)
1692 FILE *file ATTRIBUTE_UNUSED;
1694 #ifdef FUNCTION_BLOCK_PROFILER
1695 if (profile_block_flag)
1697 FUNCTION_BLOCK_PROFILER (file, count_basic_blocks);
1699 #endif /* FUNCTION_BLOCK_PROFILER */
1701 #ifndef PROFILE_BEFORE_PROLOGUE
1702 if (profile_flag)
1703 profile_function (file);
1704 #endif /* not PROFILE_BEFORE_PROLOGUE */
1707 static void
1708 profile_function (file)
1709 FILE *file;
1711 #ifndef NO_PROFILE_COUNTERS
1712 int align = MIN (BIGGEST_ALIGNMENT, LONG_TYPE_SIZE);
1713 #endif
1714 #if defined(ASM_OUTPUT_REG_PUSH)
1715 #if defined(STRUCT_VALUE_INCOMING_REGNUM) || defined(STRUCT_VALUE_REGNUM)
1716 int sval = current_function_returns_struct;
1717 #endif
1718 #if defined(STATIC_CHAIN_INCOMING_REGNUM) || defined(STATIC_CHAIN_REGNUM)
1719 int cxt = current_function_needs_context;
1720 #endif
1721 #endif /* ASM_OUTPUT_REG_PUSH */
1723 #ifndef NO_PROFILE_COUNTERS
1724 data_section ();
1725 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
1726 ASM_OUTPUT_INTERNAL_LABEL (file, "LP", profile_label_no);
1727 assemble_integer (const0_rtx, LONG_TYPE_SIZE / BITS_PER_UNIT, 1);
1728 #endif
1730 function_section (current_function_decl);
1732 #if defined(STRUCT_VALUE_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1733 if (sval)
1734 ASM_OUTPUT_REG_PUSH (file, STRUCT_VALUE_INCOMING_REGNUM);
1735 #else
1736 #if defined(STRUCT_VALUE_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1737 if (sval)
1739 ASM_OUTPUT_REG_PUSH (file, STRUCT_VALUE_REGNUM);
1741 #endif
1742 #endif
1744 #if defined(STATIC_CHAIN_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1745 if (cxt)
1746 ASM_OUTPUT_REG_PUSH (file, STATIC_CHAIN_INCOMING_REGNUM);
1747 #else
1748 #if defined(STATIC_CHAIN_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1749 if (cxt)
1751 ASM_OUTPUT_REG_PUSH (file, STATIC_CHAIN_REGNUM);
1753 #endif
1754 #endif
1756 FUNCTION_PROFILER (file, profile_label_no);
1758 #if defined(STATIC_CHAIN_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1759 if (cxt)
1760 ASM_OUTPUT_REG_POP (file, STATIC_CHAIN_INCOMING_REGNUM);
1761 #else
1762 #if defined(STATIC_CHAIN_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1763 if (cxt)
1765 ASM_OUTPUT_REG_POP (file, STATIC_CHAIN_REGNUM);
1767 #endif
1768 #endif
1770 #if defined(STRUCT_VALUE_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1771 if (sval)
1772 ASM_OUTPUT_REG_POP (file, STRUCT_VALUE_INCOMING_REGNUM);
1773 #else
1774 #if defined(STRUCT_VALUE_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1775 if (sval)
1777 ASM_OUTPUT_REG_POP (file, STRUCT_VALUE_REGNUM);
1779 #endif
1780 #endif
1783 /* Output assembler code for the end of a function.
1784 For clarity, args are same as those of `final_start_function'
1785 even though not all of them are needed. */
1787 void
1788 final_end_function (first, file, optimize)
1789 rtx first ATTRIBUTE_UNUSED;
1790 FILE *file ATTRIBUTE_UNUSED;
1791 int optimize ATTRIBUTE_UNUSED;
1793 app_disable ();
1795 #ifdef SDB_DEBUGGING_INFO
1796 if (write_symbols == SDB_DEBUG)
1797 sdbout_end_function (high_function_linenum);
1798 #endif
1800 #ifdef DWARF_DEBUGGING_INFO
1801 if (write_symbols == DWARF_DEBUG)
1802 dwarfout_end_function ();
1803 #endif
1805 #ifdef XCOFF_DEBUGGING_INFO
1806 if (write_symbols == XCOFF_DEBUG)
1807 xcoffout_end_function (file, high_function_linenum);
1808 #endif
1810 #ifdef FUNCTION_EPILOGUE
1811 /* Finally, output the function epilogue:
1812 code to restore the stack frame and return to the caller. */
1813 FUNCTION_EPILOGUE (file, get_frame_size ());
1814 #endif
1816 #ifdef SDB_DEBUGGING_INFO
1817 if (write_symbols == SDB_DEBUG)
1818 sdbout_end_epilogue ();
1819 #endif
1821 #ifdef DWARF_DEBUGGING_INFO
1822 if (write_symbols == DWARF_DEBUG)
1823 dwarfout_end_epilogue ();
1824 #endif
1826 #if defined (DWARF2_UNWIND_INFO) || defined (DWARF2_DEBUGGING_INFO)
1827 if (dwarf2out_do_frame ())
1828 dwarf2out_end_epilogue ();
1829 #endif
1831 #ifdef XCOFF_DEBUGGING_INFO
1832 if (write_symbols == XCOFF_DEBUG)
1833 xcoffout_end_epilogue (file);
1834 #endif
1836 bb_func_label_num = -1; /* not in function, nuke label # */
1838 #ifdef IA64_UNWIND_INFO
1839 output_function_exception_table ();
1840 #endif
1842 /* If FUNCTION_EPILOGUE is not defined, then the function body
1843 itself contains return instructions wherever needed. */
1846 /* Add a block to the linked list that remembers the current line/file/function
1847 for basic block profiling. Emit the label in front of the basic block and
1848 the instructions that increment the count field. */
1850 static void
1851 add_bb (file)
1852 FILE *file;
1854 struct bb_list *ptr =
1855 (struct bb_list *) permalloc (sizeof (struct bb_list));
1857 /* Add basic block to linked list. */
1858 ptr->next = 0;
1859 ptr->line_num = last_linenum;
1860 ptr->file_label_num = bb_file_label_num;
1861 ptr->func_label_num = bb_func_label_num;
1862 *bb_tail = ptr;
1863 bb_tail = &ptr->next;
1865 /* Enable the table of basic-block use counts
1866 to point at the code it applies to. */
1867 ASM_OUTPUT_INTERNAL_LABEL (file, "LPB", count_basic_blocks);
1869 /* Before first insn of this basic block, increment the
1870 count of times it was entered. */
1871 #ifdef BLOCK_PROFILER
1872 BLOCK_PROFILER (file, count_basic_blocks);
1873 #endif
1874 #ifdef HAVE_cc0
1875 CC_STATUS_INIT;
1876 #endif
1878 new_block = 0;
1879 count_basic_blocks++;
1882 /* Add a string to be used for basic block profiling. */
1884 static int
1885 add_bb_string (string, perm_p)
1886 const char *string;
1887 int perm_p;
1889 int len;
1890 struct bb_str *ptr = 0;
1892 if (!string)
1894 string = "<unknown>";
1895 perm_p = TRUE;
1898 /* Allocate a new string if the current string isn't permanent. If
1899 the string is permanent search for the same string in other
1900 allocations. */
1902 len = strlen (string) + 1;
1903 if (!perm_p)
1905 char *p = (char *) permalloc (len);
1906 memcpy (p, string, len);
1907 string = p;
1909 else
1910 for (ptr = sbb_head; ptr != (struct bb_str *) 0; ptr = ptr->next)
1911 if (ptr->string == string)
1912 break;
1914 /* Allocate a new string block if we need to. */
1915 if (!ptr)
1917 ptr = (struct bb_str *) permalloc (sizeof (*ptr));
1918 ptr->next = 0;
1919 ptr->length = len;
1920 ptr->label_num = sbb_label_num++;
1921 ptr->string = string;
1922 *sbb_tail = ptr;
1923 sbb_tail = &ptr->next;
1926 return ptr->label_num;
1929 /* Output assembler code for some insns: all or part of a function.
1930 For description of args, see `final_start_function', above.
1932 PRESCAN is 1 if we are not really outputting,
1933 just scanning as if we were outputting.
1934 Prescanning deletes and rearranges insns just like ordinary output.
1935 PRESCAN is -2 if we are outputting after having prescanned.
1936 In this case, don't try to delete or rearrange insns
1937 because that has already been done.
1938 Prescanning is done only on certain machines. */
1940 void
1941 final (first, file, optimize, prescan)
1942 rtx first;
1943 FILE *file;
1944 int optimize;
1945 int prescan;
1947 register rtx insn;
1948 int max_line = 0;
1949 int max_uid = 0;
1951 last_ignored_compare = 0;
1952 new_block = 1;
1954 check_exception_handler_labels ();
1956 /* Make a map indicating which line numbers appear in this function.
1957 When producing SDB debugging info, delete troublesome line number
1958 notes from inlined functions in other files as well as duplicate
1959 line number notes. */
1960 #ifdef SDB_DEBUGGING_INFO
1961 if (write_symbols == SDB_DEBUG)
1963 rtx last = 0;
1964 for (insn = first; insn; insn = NEXT_INSN (insn))
1965 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
1967 if ((RTX_INTEGRATED_P (insn)
1968 && strcmp (NOTE_SOURCE_FILE (insn), main_input_filename) != 0)
1969 || (last != 0
1970 && NOTE_LINE_NUMBER (insn) == NOTE_LINE_NUMBER (last)
1971 && NOTE_SOURCE_FILE (insn) == NOTE_SOURCE_FILE (last)))
1973 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
1974 NOTE_SOURCE_FILE (insn) = 0;
1975 continue;
1977 last = insn;
1978 if (NOTE_LINE_NUMBER (insn) > max_line)
1979 max_line = NOTE_LINE_NUMBER (insn);
1982 else
1983 #endif
1985 for (insn = first; insn; insn = NEXT_INSN (insn))
1986 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > max_line)
1987 max_line = NOTE_LINE_NUMBER (insn);
1990 line_note_exists = (char *) xcalloc (max_line + 1, sizeof (char));
1992 for (insn = first; insn; insn = NEXT_INSN (insn))
1994 if (INSN_UID (insn) > max_uid) /* find largest UID */
1995 max_uid = INSN_UID (insn);
1996 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
1997 line_note_exists[NOTE_LINE_NUMBER (insn)] = 1;
1998 #ifdef HAVE_cc0
1999 /* If CC tracking across branches is enabled, record the insn which
2000 jumps to each branch only reached from one place. */
2001 if (optimize && GET_CODE (insn) == JUMP_INSN)
2003 rtx lab = JUMP_LABEL (insn);
2004 if (lab && LABEL_NUSES (lab) == 1)
2006 LABEL_REFS (lab) = insn;
2009 #endif
2012 /* Initialize insn_eh_region table if eh is being used. */
2014 init_insn_eh_region (first, max_uid);
2016 init_recog ();
2018 CC_STATUS_INIT;
2020 /* Output the insns. */
2021 for (insn = NEXT_INSN (first); insn;)
2023 #ifdef HAVE_ATTR_length
2024 if (INSN_UID (insn) >= INSN_ADDRESSES_SIZE ())
2026 #ifdef STACK_REGS
2027 /* Irritatingly, the reg-stack pass is creating new instructions
2028 and because of REG_DEAD note abuse it has to run after
2029 shorten_branches. Fake address of -1 then. */
2030 insn_current_address = -1;
2031 #else
2032 /* This can be triggered by bugs elsewhere in the compiler if
2033 new insns are created after init_insn_lengths is called. */
2034 abort ();
2035 #endif
2037 else
2038 insn_current_address = INSN_ADDRESSES (INSN_UID (insn));
2039 #endif /* HAVE_ATTR_length */
2041 insn = final_scan_insn (insn, file, optimize, prescan, 0);
2044 /* Do basic-block profiling here
2045 if the last insn was a conditional branch. */
2046 if (profile_block_flag && new_block)
2047 add_bb (file);
2049 free_insn_eh_region ();
2050 free (line_note_exists);
2051 line_note_exists = NULL;
2054 const char *
2055 get_insn_template (code, insn)
2056 int code;
2057 rtx insn;
2059 const void *output = insn_data[code].output;
2060 switch (insn_data[code].output_format)
2062 case INSN_OUTPUT_FORMAT_SINGLE:
2063 return (const char *) output;
2064 case INSN_OUTPUT_FORMAT_MULTI:
2065 return ((const char *const *) output)[which_alternative];
2066 case INSN_OUTPUT_FORMAT_FUNCTION:
2067 if (insn == NULL)
2068 abort ();
2069 return (*(insn_output_fn) output) (recog_data.operand, insn);
2071 default:
2072 abort ();
2076 /* The final scan for one insn, INSN.
2077 Args are same as in `final', except that INSN
2078 is the insn being scanned.
2079 Value returned is the next insn to be scanned.
2081 NOPEEPHOLES is the flag to disallow peephole processing (currently
2082 used for within delayed branch sequence output). */
2085 final_scan_insn (insn, file, optimize, prescan, nopeepholes)
2086 rtx insn;
2087 FILE *file;
2088 int optimize ATTRIBUTE_UNUSED;
2089 int prescan;
2090 int nopeepholes ATTRIBUTE_UNUSED;
2092 #ifdef HAVE_cc0
2093 rtx set;
2094 #endif
2096 insn_counter++;
2098 /* Ignore deleted insns. These can occur when we split insns (due to a
2099 template of "#") while not optimizing. */
2100 if (INSN_DELETED_P (insn))
2101 return NEXT_INSN (insn);
2103 switch (GET_CODE (insn))
2105 case NOTE:
2106 if (prescan > 0)
2107 break;
2109 switch (NOTE_LINE_NUMBER (insn))
2111 case NOTE_INSN_DELETED:
2112 case NOTE_INSN_LOOP_BEG:
2113 case NOTE_INSN_LOOP_END:
2114 case NOTE_INSN_LOOP_CONT:
2115 case NOTE_INSN_LOOP_VTOP:
2116 case NOTE_INSN_FUNCTION_END:
2117 case NOTE_INSN_SETJMP:
2118 case NOTE_INSN_REPEATED_LINE_NUMBER:
2119 case NOTE_INSN_RANGE_BEG:
2120 case NOTE_INSN_RANGE_END:
2121 case NOTE_INSN_LIVE:
2122 case NOTE_INSN_EXPECTED_VALUE:
2123 break;
2125 case NOTE_INSN_BASIC_BLOCK:
2126 if (flag_debug_asm)
2127 fprintf (asm_out_file, "\t%s basic block %d\n",
2128 ASM_COMMENT_START, NOTE_BASIC_BLOCK (insn)->index);
2129 break;
2131 case NOTE_INSN_EH_REGION_BEG:
2132 if (! exceptions_via_longjmp)
2134 ASM_OUTPUT_INTERNAL_LABEL (file, "LEHB", NOTE_EH_HANDLER (insn));
2135 if (! flag_new_exceptions)
2136 add_eh_table_entry (NOTE_EH_HANDLER (insn));
2137 #ifdef ASM_OUTPUT_EH_REGION_BEG
2138 ASM_OUTPUT_EH_REGION_BEG (file, NOTE_EH_HANDLER (insn));
2139 #endif
2141 break;
2143 case NOTE_INSN_EH_REGION_END:
2144 if (! exceptions_via_longjmp)
2146 ASM_OUTPUT_INTERNAL_LABEL (file, "LEHE", NOTE_EH_HANDLER (insn));
2147 if (flag_new_exceptions)
2148 add_eh_table_entry (NOTE_EH_HANDLER (insn));
2149 #ifdef ASM_OUTPUT_EH_REGION_END
2150 ASM_OUTPUT_EH_REGION_END (file, NOTE_EH_HANDLER (insn));
2151 #endif
2153 break;
2155 case NOTE_INSN_PROLOGUE_END:
2156 #ifdef FUNCTION_END_PROLOGUE
2157 FUNCTION_END_PROLOGUE (file);
2158 #endif
2159 profile_after_prologue (file);
2160 break;
2162 case NOTE_INSN_EPILOGUE_BEG:
2163 #ifdef FUNCTION_BEGIN_EPILOGUE
2164 FUNCTION_BEGIN_EPILOGUE (file);
2165 #endif
2166 break;
2168 case NOTE_INSN_FUNCTION_BEG:
2169 #if defined(SDB_DEBUGGING_INFO) && defined(MIPS_DEBUGGING_INFO)
2170 /* MIPS stabs require the parameter descriptions to be after the
2171 function entry point rather than before. */
2172 if (write_symbols == SDB_DEBUG)
2174 app_disable ();
2175 sdbout_begin_function (last_linenum);
2177 #endif
2178 #ifdef DWARF_DEBUGGING_INFO
2179 /* This outputs a marker where the function body starts, so it
2180 must be after the prologue. */
2181 if (write_symbols == DWARF_DEBUG)
2183 app_disable ();
2184 dwarfout_begin_function ();
2186 #endif
2187 break;
2189 case NOTE_INSN_BLOCK_BEG:
2190 if (debug_info_level == DINFO_LEVEL_NORMAL
2191 || debug_info_level == DINFO_LEVEL_VERBOSE
2192 || write_symbols == DWARF_DEBUG
2193 || write_symbols == DWARF2_DEBUG)
2195 int n = BLOCK_NUMBER (NOTE_BLOCK (insn));
2197 app_disable ();
2198 ++block_depth;
2199 high_block_linenum = last_linenum;
2201 /* Output debugging info about the symbol-block beginning. */
2202 #ifdef SDB_DEBUGGING_INFO
2203 if (write_symbols == SDB_DEBUG)
2204 sdbout_begin_block (file, last_linenum, n);
2205 #endif
2206 #ifdef XCOFF_DEBUGGING_INFO
2207 if (write_symbols == XCOFF_DEBUG)
2208 xcoffout_begin_block (file, last_linenum, n);
2209 #endif
2210 #ifdef DBX_DEBUGGING_INFO
2211 if (write_symbols == DBX_DEBUG)
2212 ASM_OUTPUT_INTERNAL_LABEL (file, "LBB", n);
2213 #endif
2214 #ifdef DWARF_DEBUGGING_INFO
2215 if (write_symbols == DWARF_DEBUG)
2216 dwarfout_begin_block (n);
2217 #endif
2218 #ifdef DWARF2_DEBUGGING_INFO
2219 if (write_symbols == DWARF2_DEBUG)
2220 dwarf2out_begin_block (n);
2221 #endif
2223 /* Mark this block as output. */
2224 TREE_ASM_WRITTEN (NOTE_BLOCK (insn)) = 1;
2226 break;
2228 case NOTE_INSN_BLOCK_END:
2229 if (debug_info_level == DINFO_LEVEL_NORMAL
2230 || debug_info_level == DINFO_LEVEL_VERBOSE
2231 || write_symbols == DWARF_DEBUG
2232 || write_symbols == DWARF2_DEBUG)
2234 int n = BLOCK_NUMBER (NOTE_BLOCK (insn));
2236 app_disable ();
2238 /* End of a symbol-block. */
2239 --block_depth;
2240 if (block_depth < 0)
2241 abort ();
2243 #ifdef XCOFF_DEBUGGING_INFO
2244 if (write_symbols == XCOFF_DEBUG)
2245 xcoffout_end_block (file, high_block_linenum, n);
2246 #endif
2247 #ifdef DBX_DEBUGGING_INFO
2248 if (write_symbols == DBX_DEBUG)
2249 ASM_OUTPUT_INTERNAL_LABEL (file, "LBE", n);
2250 #endif
2251 #ifdef SDB_DEBUGGING_INFO
2252 if (write_symbols == SDB_DEBUG)
2253 sdbout_end_block (file, high_block_linenum, n);
2254 #endif
2255 #ifdef DWARF_DEBUGGING_INFO
2256 if (write_symbols == DWARF_DEBUG)
2257 dwarfout_end_block (n);
2258 #endif
2259 #ifdef DWARF2_DEBUGGING_INFO
2260 if (write_symbols == DWARF2_DEBUG)
2261 dwarf2out_end_block (n);
2262 #endif
2264 break;
2266 case NOTE_INSN_DELETED_LABEL:
2267 /* Emit the label. We may have deleted the CODE_LABEL because
2268 the label could be proved to be unreachable, though still
2269 referenced (in the form of having its address taken. */
2270 ASM_OUTPUT_DEBUG_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
2271 break;
2273 case 0:
2274 break;
2276 default:
2277 if (NOTE_LINE_NUMBER (insn) <= 0)
2278 abort ();
2280 /* This note is a line-number. */
2282 register rtx note;
2283 int note_after = 0;
2285 /* If there is anything real after this note, output it.
2286 If another line note follows, omit this one. */
2287 for (note = NEXT_INSN (insn); note; note = NEXT_INSN (note))
2289 if (GET_CODE (note) != NOTE && GET_CODE (note) != CODE_LABEL)
2290 break;
2292 /* These types of notes can be significant
2293 so make sure the preceding line number stays. */
2294 else if (GET_CODE (note) == NOTE
2295 && (NOTE_LINE_NUMBER (note) == NOTE_INSN_BLOCK_BEG
2296 || NOTE_LINE_NUMBER (note) == NOTE_INSN_BLOCK_END
2297 || NOTE_LINE_NUMBER (note) == NOTE_INSN_FUNCTION_BEG))
2298 break;
2299 else if (GET_CODE (note) == NOTE && NOTE_LINE_NUMBER (note) > 0)
2301 /* Another line note follows; we can delete this note
2302 if no intervening line numbers have notes elsewhere. */
2303 int num;
2304 for (num = NOTE_LINE_NUMBER (insn) + 1;
2305 num < NOTE_LINE_NUMBER (note);
2306 num++)
2307 if (line_note_exists[num])
2308 break;
2310 if (num >= NOTE_LINE_NUMBER (note))
2311 note_after = 1;
2312 break;
2316 /* Output this line note if it is the first or the last line
2317 note in a row. */
2318 if (!note_after)
2319 output_source_line (file, insn);
2321 break;
2323 break;
2325 case BARRIER:
2326 #if defined (DWARF2_UNWIND_INFO)
2327 /* If we push arguments, we need to check all insns for stack
2328 adjustments. */
2329 if (!ACCUMULATE_OUTGOING_ARGS && dwarf2out_do_frame ())
2330 dwarf2out_frame_debug (insn);
2331 #endif
2332 break;
2334 case CODE_LABEL:
2335 /* The target port might emit labels in the output function for
2336 some insn, e.g. sh.c output_branchy_insn. */
2337 if (CODE_LABEL_NUMBER (insn) <= max_labelno)
2339 int align = LABEL_TO_ALIGNMENT (insn);
2340 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
2341 int max_skip = LABEL_TO_MAX_SKIP (insn);
2342 #endif
2344 if (align && NEXT_INSN (insn))
2345 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
2346 ASM_OUTPUT_MAX_SKIP_ALIGN (file, align, max_skip);
2347 #else
2348 ASM_OUTPUT_ALIGN (file, align);
2349 #endif
2351 #ifdef HAVE_cc0
2352 CC_STATUS_INIT;
2353 /* If this label is reached from only one place, set the condition
2354 codes from the instruction just before the branch. */
2356 /* Disabled because some insns set cc_status in the C output code
2357 and NOTICE_UPDATE_CC alone can set incorrect status. */
2358 if (0 /* optimize && LABEL_NUSES (insn) == 1*/)
2360 rtx jump = LABEL_REFS (insn);
2361 rtx barrier = prev_nonnote_insn (insn);
2362 rtx prev;
2363 /* If the LABEL_REFS field of this label has been set to point
2364 at a branch, the predecessor of the branch is a regular
2365 insn, and that branch is the only way to reach this label,
2366 set the condition codes based on the branch and its
2367 predecessor. */
2368 if (barrier && GET_CODE (barrier) == BARRIER
2369 && jump && GET_CODE (jump) == JUMP_INSN
2370 && (prev = prev_nonnote_insn (jump))
2371 && GET_CODE (prev) == INSN)
2373 NOTICE_UPDATE_CC (PATTERN (prev), prev);
2374 NOTICE_UPDATE_CC (PATTERN (jump), jump);
2377 #endif
2378 if (prescan > 0)
2379 break;
2380 new_block = 1;
2382 #ifdef FINAL_PRESCAN_LABEL
2383 FINAL_PRESCAN_INSN (insn, NULL_PTR, 0);
2384 #endif
2386 #ifdef SDB_DEBUGGING_INFO
2387 if (write_symbols == SDB_DEBUG && LABEL_NAME (insn))
2388 sdbout_label (insn);
2389 #endif
2390 if (app_on)
2392 fputs (ASM_APP_OFF, file);
2393 app_on = 0;
2395 if (NEXT_INSN (insn) != 0
2396 && GET_CODE (NEXT_INSN (insn)) == JUMP_INSN)
2398 rtx nextbody = PATTERN (NEXT_INSN (insn));
2400 /* If this label is followed by a jump-table,
2401 make sure we put the label in the read-only section. Also
2402 possibly write the label and jump table together. */
2404 if (GET_CODE (nextbody) == ADDR_VEC
2405 || GET_CODE (nextbody) == ADDR_DIFF_VEC)
2407 #if defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC)
2408 /* In this case, the case vector is being moved by the
2409 target, so don't output the label at all. Leave that
2410 to the back end macros. */
2411 #else
2412 if (! JUMP_TABLES_IN_TEXT_SECTION)
2414 readonly_data_section ();
2415 #ifdef READONLY_DATA_SECTION
2416 ASM_OUTPUT_ALIGN (file,
2417 exact_log2 (BIGGEST_ALIGNMENT
2418 / BITS_PER_UNIT));
2419 #endif /* READONLY_DATA_SECTION */
2421 else
2422 function_section (current_function_decl);
2424 #ifdef ASM_OUTPUT_CASE_LABEL
2425 ASM_OUTPUT_CASE_LABEL (file, "L", CODE_LABEL_NUMBER (insn),
2426 NEXT_INSN (insn));
2427 #else
2428 if (LABEL_ALTERNATE_NAME (insn))
2429 ASM_OUTPUT_ALTERNATE_LABEL_NAME (file, insn);
2430 else
2431 ASM_OUTPUT_INTERNAL_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
2432 #endif
2433 #endif
2434 break;
2437 if (LABEL_ALTERNATE_NAME (insn))
2438 ASM_OUTPUT_ALTERNATE_LABEL_NAME (file, insn);
2439 else
2440 ASM_OUTPUT_INTERNAL_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
2441 break;
2443 default:
2445 register rtx body = PATTERN (insn);
2446 int insn_code_number;
2447 const char *template;
2448 #ifdef HAVE_cc0
2449 rtx note;
2450 #endif
2452 /* An INSN, JUMP_INSN or CALL_INSN.
2453 First check for special kinds that recog doesn't recognize. */
2455 if (GET_CODE (body) == USE /* These are just declarations */
2456 || GET_CODE (body) == CLOBBER)
2457 break;
2459 #ifdef HAVE_cc0
2460 /* If there is a REG_CC_SETTER note on this insn, it means that
2461 the setting of the condition code was done in the delay slot
2462 of the insn that branched here. So recover the cc status
2463 from the insn that set it. */
2465 note = find_reg_note (insn, REG_CC_SETTER, NULL_RTX);
2466 if (note)
2468 NOTICE_UPDATE_CC (PATTERN (XEXP (note, 0)), XEXP (note, 0));
2469 cc_prev_status = cc_status;
2471 #endif
2473 /* Detect insns that are really jump-tables
2474 and output them as such. */
2476 if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
2478 #if !(defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC))
2479 register int vlen, idx;
2480 #endif
2482 if (prescan > 0)
2483 break;
2485 if (app_on)
2487 fputs (ASM_APP_OFF, file);
2488 app_on = 0;
2491 #if defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC)
2492 if (GET_CODE (body) == ADDR_VEC)
2494 #ifdef ASM_OUTPUT_ADDR_VEC
2495 ASM_OUTPUT_ADDR_VEC (PREV_INSN (insn), body);
2496 #else
2497 abort ();
2498 #endif
2500 else
2502 #ifdef ASM_OUTPUT_ADDR_DIFF_VEC
2503 ASM_OUTPUT_ADDR_DIFF_VEC (PREV_INSN (insn), body);
2504 #else
2505 abort ();
2506 #endif
2508 #else
2509 vlen = XVECLEN (body, GET_CODE (body) == ADDR_DIFF_VEC);
2510 for (idx = 0; idx < vlen; idx++)
2512 if (GET_CODE (body) == ADDR_VEC)
2514 #ifdef ASM_OUTPUT_ADDR_VEC_ELT
2515 ASM_OUTPUT_ADDR_VEC_ELT
2516 (file, CODE_LABEL_NUMBER (XEXP (XVECEXP (body, 0, idx), 0)));
2517 #else
2518 abort ();
2519 #endif
2521 else
2523 #ifdef ASM_OUTPUT_ADDR_DIFF_ELT
2524 ASM_OUTPUT_ADDR_DIFF_ELT
2525 (file,
2526 body,
2527 CODE_LABEL_NUMBER (XEXP (XVECEXP (body, 1, idx), 0)),
2528 CODE_LABEL_NUMBER (XEXP (XEXP (body, 0), 0)));
2529 #else
2530 abort ();
2531 #endif
2534 #ifdef ASM_OUTPUT_CASE_END
2535 ASM_OUTPUT_CASE_END (file,
2536 CODE_LABEL_NUMBER (PREV_INSN (insn)),
2537 insn);
2538 #endif
2539 #endif
2541 function_section (current_function_decl);
2543 break;
2546 /* Do basic-block profiling when we reach a new block.
2547 Done here to avoid jump tables. */
2548 if (profile_block_flag && new_block)
2549 add_bb (file);
2551 if (GET_CODE (body) == ASM_INPUT)
2553 /* There's no telling what that did to the condition codes. */
2554 CC_STATUS_INIT;
2555 if (prescan > 0)
2556 break;
2557 if (! app_on)
2559 fputs (ASM_APP_ON, file);
2560 app_on = 1;
2562 fprintf (asm_out_file, "\t%s\n", XSTR (body, 0));
2563 break;
2566 /* Detect `asm' construct with operands. */
2567 if (asm_noperands (body) >= 0)
2569 unsigned int noperands = asm_noperands (body);
2570 rtx *ops = (rtx *) alloca (noperands * sizeof (rtx));
2571 const char *string;
2573 /* There's no telling what that did to the condition codes. */
2574 CC_STATUS_INIT;
2575 if (prescan > 0)
2576 break;
2578 if (! app_on)
2580 fputs (ASM_APP_ON, file);
2581 app_on = 1;
2584 /* Get out the operand values. */
2585 string = decode_asm_operands (body, ops, NULL_PTR,
2586 NULL_PTR, NULL_PTR);
2587 /* Inhibit aborts on what would otherwise be compiler bugs. */
2588 insn_noperands = noperands;
2589 this_is_asm_operands = insn;
2591 /* Output the insn using them. */
2592 output_asm_insn (string, ops);
2593 this_is_asm_operands = 0;
2594 break;
2597 if (prescan <= 0 && app_on)
2599 fputs (ASM_APP_OFF, file);
2600 app_on = 0;
2603 if (GET_CODE (body) == SEQUENCE)
2605 /* A delayed-branch sequence */
2606 register int i;
2607 rtx next;
2609 if (prescan > 0)
2610 break;
2611 final_sequence = body;
2613 /* The first insn in this SEQUENCE might be a JUMP_INSN that will
2614 force the restoration of a comparison that was previously
2615 thought unnecessary. If that happens, cancel this sequence
2616 and cause that insn to be restored. */
2618 next = final_scan_insn (XVECEXP (body, 0, 0), file, 0, prescan, 1);
2619 if (next != XVECEXP (body, 0, 1))
2621 final_sequence = 0;
2622 return next;
2625 for (i = 1; i < XVECLEN (body, 0); i++)
2627 rtx insn = XVECEXP (body, 0, i);
2628 rtx next = NEXT_INSN (insn);
2629 /* We loop in case any instruction in a delay slot gets
2630 split. */
2632 insn = final_scan_insn (insn, file, 0, prescan, 1);
2633 while (insn != next);
2635 #ifdef DBR_OUTPUT_SEQEND
2636 DBR_OUTPUT_SEQEND (file);
2637 #endif
2638 final_sequence = 0;
2640 /* If the insn requiring the delay slot was a CALL_INSN, the
2641 insns in the delay slot are actually executed before the
2642 called function. Hence we don't preserve any CC-setting
2643 actions in these insns and the CC must be marked as being
2644 clobbered by the function. */
2645 if (GET_CODE (XVECEXP (body, 0, 0)) == CALL_INSN)
2647 CC_STATUS_INIT;
2650 /* Following a conditional branch sequence, we have a new basic
2651 block. */
2652 if (profile_block_flag)
2654 rtx insn = XVECEXP (body, 0, 0);
2655 rtx body = PATTERN (insn);
2657 if ((GET_CODE (insn) == JUMP_INSN && GET_CODE (body) == SET
2658 && GET_CODE (SET_SRC (body)) != LABEL_REF)
2659 || (GET_CODE (insn) == JUMP_INSN
2660 && GET_CODE (body) == PARALLEL
2661 && GET_CODE (XVECEXP (body, 0, 0)) == SET
2662 && GET_CODE (SET_SRC (XVECEXP (body, 0, 0))) != LABEL_REF))
2663 new_block = 1;
2665 break;
2668 /* We have a real machine instruction as rtl. */
2670 body = PATTERN (insn);
2672 #ifdef HAVE_cc0
2673 set = single_set (insn);
2675 /* Check for redundant test and compare instructions
2676 (when the condition codes are already set up as desired).
2677 This is done only when optimizing; if not optimizing,
2678 it should be possible for the user to alter a variable
2679 with the debugger in between statements
2680 and the next statement should reexamine the variable
2681 to compute the condition codes. */
2683 if (optimize)
2685 #if 0
2686 rtx set = single_set (insn);
2687 #endif
2689 if (set
2690 && GET_CODE (SET_DEST (set)) == CC0
2691 && insn != last_ignored_compare)
2693 if (GET_CODE (SET_SRC (set)) == SUBREG)
2694 SET_SRC (set) = alter_subreg (SET_SRC (set));
2695 else if (GET_CODE (SET_SRC (set)) == COMPARE)
2697 if (GET_CODE (XEXP (SET_SRC (set), 0)) == SUBREG)
2698 XEXP (SET_SRC (set), 0)
2699 = alter_subreg (XEXP (SET_SRC (set), 0));
2700 if (GET_CODE (XEXP (SET_SRC (set), 1)) == SUBREG)
2701 XEXP (SET_SRC (set), 1)
2702 = alter_subreg (XEXP (SET_SRC (set), 1));
2704 if ((cc_status.value1 != 0
2705 && rtx_equal_p (SET_SRC (set), cc_status.value1))
2706 || (cc_status.value2 != 0
2707 && rtx_equal_p (SET_SRC (set), cc_status.value2)))
2709 /* Don't delete insn if it has an addressing side-effect. */
2710 if (! FIND_REG_INC_NOTE (insn, 0)
2711 /* or if anything in it is volatile. */
2712 && ! volatile_refs_p (PATTERN (insn)))
2714 /* We don't really delete the insn; just ignore it. */
2715 last_ignored_compare = insn;
2716 break;
2721 #endif
2723 /* Following a conditional branch, we have a new basic block.
2724 But if we are inside a sequence, the new block starts after the
2725 last insn of the sequence. */
2726 if (profile_block_flag && final_sequence == 0
2727 && ((GET_CODE (insn) == JUMP_INSN && GET_CODE (body) == SET
2728 && GET_CODE (SET_SRC (body)) != LABEL_REF)
2729 || (GET_CODE (insn) == JUMP_INSN && GET_CODE (body) == PARALLEL
2730 && GET_CODE (XVECEXP (body, 0, 0)) == SET
2731 && GET_CODE (SET_SRC (XVECEXP (body, 0, 0))) != LABEL_REF)))
2732 new_block = 1;
2734 #ifndef STACK_REGS
2735 /* Don't bother outputting obvious no-ops, even without -O.
2736 This optimization is fast and doesn't interfere with debugging.
2737 Don't do this if the insn is in a delay slot, since this
2738 will cause an improper number of delay insns to be written. */
2739 if (final_sequence == 0
2740 && prescan >= 0
2741 && GET_CODE (insn) == INSN && GET_CODE (body) == SET
2742 && GET_CODE (SET_SRC (body)) == REG
2743 && GET_CODE (SET_DEST (body)) == REG
2744 && REGNO (SET_SRC (body)) == REGNO (SET_DEST (body)))
2745 break;
2746 #endif
2748 #ifdef HAVE_cc0
2749 /* If this is a conditional branch, maybe modify it
2750 if the cc's are in a nonstandard state
2751 so that it accomplishes the same thing that it would
2752 do straightforwardly if the cc's were set up normally. */
2754 if (cc_status.flags != 0
2755 && GET_CODE (insn) == JUMP_INSN
2756 && GET_CODE (body) == SET
2757 && SET_DEST (body) == pc_rtx
2758 && GET_CODE (SET_SRC (body)) == IF_THEN_ELSE
2759 && GET_RTX_CLASS (GET_CODE (XEXP (SET_SRC (body), 0))) == '<'
2760 && XEXP (XEXP (SET_SRC (body), 0), 0) == cc0_rtx
2761 /* This is done during prescan; it is not done again
2762 in final scan when prescan has been done. */
2763 && prescan >= 0)
2765 /* This function may alter the contents of its argument
2766 and clear some of the cc_status.flags bits.
2767 It may also return 1 meaning condition now always true
2768 or -1 meaning condition now always false
2769 or 2 meaning condition nontrivial but altered. */
2770 register int result = alter_cond (XEXP (SET_SRC (body), 0));
2771 /* If condition now has fixed value, replace the IF_THEN_ELSE
2772 with its then-operand or its else-operand. */
2773 if (result == 1)
2774 SET_SRC (body) = XEXP (SET_SRC (body), 1);
2775 if (result == -1)
2776 SET_SRC (body) = XEXP (SET_SRC (body), 2);
2778 /* The jump is now either unconditional or a no-op.
2779 If it has become a no-op, don't try to output it.
2780 (It would not be recognized.) */
2781 if (SET_SRC (body) == pc_rtx)
2783 PUT_CODE (insn, NOTE);
2784 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2785 NOTE_SOURCE_FILE (insn) = 0;
2786 break;
2788 else if (GET_CODE (SET_SRC (body)) == RETURN)
2789 /* Replace (set (pc) (return)) with (return). */
2790 PATTERN (insn) = body = SET_SRC (body);
2792 /* Rerecognize the instruction if it has changed. */
2793 if (result != 0)
2794 INSN_CODE (insn) = -1;
2797 /* Make same adjustments to instructions that examine the
2798 condition codes without jumping and instructions that
2799 handle conditional moves (if this machine has either one). */
2801 if (cc_status.flags != 0
2802 && set != 0)
2804 rtx cond_rtx, then_rtx, else_rtx;
2806 if (GET_CODE (insn) != JUMP_INSN
2807 && GET_CODE (SET_SRC (set)) == IF_THEN_ELSE)
2809 cond_rtx = XEXP (SET_SRC (set), 0);
2810 then_rtx = XEXP (SET_SRC (set), 1);
2811 else_rtx = XEXP (SET_SRC (set), 2);
2813 else
2815 cond_rtx = SET_SRC (set);
2816 then_rtx = const_true_rtx;
2817 else_rtx = const0_rtx;
2820 switch (GET_CODE (cond_rtx))
2822 case GTU:
2823 case GT:
2824 case LTU:
2825 case LT:
2826 case GEU:
2827 case GE:
2828 case LEU:
2829 case LE:
2830 case EQ:
2831 case NE:
2833 register int result;
2834 if (XEXP (cond_rtx, 0) != cc0_rtx)
2835 break;
2836 result = alter_cond (cond_rtx);
2837 if (result == 1)
2838 validate_change (insn, &SET_SRC (set), then_rtx, 0);
2839 else if (result == -1)
2840 validate_change (insn, &SET_SRC (set), else_rtx, 0);
2841 else if (result == 2)
2842 INSN_CODE (insn) = -1;
2843 if (SET_DEST (set) == SET_SRC (set))
2845 PUT_CODE (insn, NOTE);
2846 NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
2847 NOTE_SOURCE_FILE (insn) = 0;
2850 break;
2852 default:
2853 break;
2857 #endif
2859 #ifdef HAVE_peephole
2860 /* Do machine-specific peephole optimizations if desired. */
2862 if (optimize && !flag_no_peephole && !nopeepholes)
2864 rtx next = peephole (insn);
2865 /* When peepholing, if there were notes within the peephole,
2866 emit them before the peephole. */
2867 if (next != 0 && next != NEXT_INSN (insn))
2869 rtx prev = PREV_INSN (insn);
2870 rtx note;
2872 for (note = NEXT_INSN (insn); note != next;
2873 note = NEXT_INSN (note))
2874 final_scan_insn (note, file, optimize, prescan, nopeepholes);
2876 /* In case this is prescan, put the notes
2877 in proper position for later rescan. */
2878 note = NEXT_INSN (insn);
2879 PREV_INSN (note) = prev;
2880 NEXT_INSN (prev) = note;
2881 NEXT_INSN (PREV_INSN (next)) = insn;
2882 PREV_INSN (insn) = PREV_INSN (next);
2883 NEXT_INSN (insn) = next;
2884 PREV_INSN (next) = insn;
2887 /* PEEPHOLE might have changed this. */
2888 body = PATTERN (insn);
2890 #endif
2892 /* Try to recognize the instruction.
2893 If successful, verify that the operands satisfy the
2894 constraints for the instruction. Crash if they don't,
2895 since `reload' should have changed them so that they do. */
2897 insn_code_number = recog_memoized (insn);
2898 cleanup_subreg_operands (insn);
2900 /* Dump the insn in the assembly for debugging. */
2901 if (flag_dump_rtl_in_asm)
2903 print_rtx_head = ASM_COMMENT_START;
2904 print_rtl_single (asm_out_file, insn);
2905 print_rtx_head = "";
2908 if (! constrain_operands_cached (1))
2909 fatal_insn_not_found (insn);
2911 /* Some target machines need to prescan each insn before
2912 it is output. */
2914 #ifdef FINAL_PRESCAN_INSN
2915 FINAL_PRESCAN_INSN (insn, recog_data.operand, recog_data.n_operands);
2916 #endif
2918 #ifdef HAVE_conditional_execution
2919 if (GET_CODE (PATTERN (insn)) == COND_EXEC)
2920 current_insn_predicate = COND_EXEC_TEST (PATTERN (insn));
2921 else
2922 current_insn_predicate = NULL_RTX;
2923 #endif
2925 #ifdef HAVE_cc0
2926 cc_prev_status = cc_status;
2928 /* Update `cc_status' for this instruction.
2929 The instruction's output routine may change it further.
2930 If the output routine for a jump insn needs to depend
2931 on the cc status, it should look at cc_prev_status. */
2933 NOTICE_UPDATE_CC (body, insn);
2934 #endif
2936 current_output_insn = debug_insn = insn;
2938 #if defined (DWARF2_UNWIND_INFO)
2939 /* If we push arguments, we want to know where the calls are. */
2940 if (!ACCUMULATE_OUTGOING_ARGS && GET_CODE (insn) == CALL_INSN
2941 && dwarf2out_do_frame ())
2942 dwarf2out_frame_debug (insn);
2943 #endif
2945 /* Find the proper template for this insn. */
2946 template = get_insn_template (insn_code_number, insn);
2948 /* If the C code returns 0, it means that it is a jump insn
2949 which follows a deleted test insn, and that test insn
2950 needs to be reinserted. */
2951 if (template == 0)
2953 rtx prev;
2955 if (prev_nonnote_insn (insn) != last_ignored_compare)
2956 abort ();
2957 new_block = 0;
2959 /* We have already processed the notes between the setter and
2960 the user. Make sure we don't process them again, this is
2961 particularly important if one of the notes is a block
2962 scope note or an EH note. */
2963 for (prev = insn;
2964 prev != last_ignored_compare;
2965 prev = PREV_INSN (prev))
2967 if (GET_CODE (prev) == NOTE)
2969 NOTE_LINE_NUMBER (prev) = NOTE_INSN_DELETED;
2970 NOTE_SOURCE_FILE (prev) = 0;
2974 return prev;
2977 /* If the template is the string "#", it means that this insn must
2978 be split. */
2979 if (template[0] == '#' && template[1] == '\0')
2981 rtx new = try_split (body, insn, 0);
2983 /* If we didn't split the insn, go away. */
2984 if (new == insn && PATTERN (new) == body)
2985 fatal_insn ("Could not split insn", insn);
2987 #ifdef HAVE_ATTR_length
2988 /* This instruction should have been split in shorten_branches,
2989 to ensure that we would have valid length info for the
2990 splitees. */
2991 abort ();
2992 #endif
2994 new_block = 0;
2995 return new;
2998 if (prescan > 0)
2999 break;
3001 #ifdef IA64_UNWIND_INFO
3002 IA64_UNWIND_EMIT (asm_out_file, insn);
3003 #endif
3004 /* Output assembler code from the template. */
3006 output_asm_insn (template, recog_data.operand);
3008 #if defined (DWARF2_UNWIND_INFO)
3009 /* If we push arguments, we need to check all insns for stack
3010 adjustments. */
3011 if (!ACCUMULATE_OUTGOING_ARGS)
3013 if (GET_CODE (insn) == INSN && dwarf2out_do_frame ())
3014 dwarf2out_frame_debug (insn);
3016 else
3018 #if defined (HAVE_prologue)
3019 /* If this insn is part of the prologue, emit DWARF v2
3020 call frame info. */
3021 if (RTX_FRAME_RELATED_P (insn) && dwarf2out_do_frame ())
3022 dwarf2out_frame_debug (insn);
3023 #endif
3025 #endif
3027 #if 0
3028 /* It's not at all clear why we did this and doing so interferes
3029 with tests we'd like to do to use REG_WAS_0 notes, so let's try
3030 with this out. */
3032 /* Mark this insn as having been output. */
3033 INSN_DELETED_P (insn) = 1;
3034 #endif
3036 current_output_insn = debug_insn = 0;
3039 return NEXT_INSN (insn);
3042 /* Output debugging info to the assembler file FILE
3043 based on the NOTE-insn INSN, assumed to be a line number. */
3045 static void
3046 output_source_line (file, insn)
3047 FILE *file ATTRIBUTE_UNUSED;
3048 rtx insn;
3050 register const char *filename = NOTE_SOURCE_FILE (insn);
3052 /* Remember filename for basic block profiling.
3053 Filenames are allocated on the permanent obstack
3054 or are passed in ARGV, so we don't have to save
3055 the string. */
3057 if (profile_block_flag && last_filename != filename)
3058 bb_file_label_num = add_bb_string (filename, TRUE);
3060 last_filename = filename;
3061 last_linenum = NOTE_LINE_NUMBER (insn);
3062 high_block_linenum = MAX (last_linenum, high_block_linenum);
3063 high_function_linenum = MAX (last_linenum, high_function_linenum);
3065 if (write_symbols != NO_DEBUG)
3067 #ifdef SDB_DEBUGGING_INFO
3068 if (write_symbols == SDB_DEBUG
3069 #if 0 /* People like having line numbers even in wrong file! */
3070 /* COFF can't handle multiple source files--lose, lose. */
3071 && !strcmp (filename, main_input_filename)
3072 #endif
3073 /* COFF relative line numbers must be positive. */
3074 && last_linenum > sdb_begin_function_line)
3076 #ifdef ASM_OUTPUT_SOURCE_LINE
3077 ASM_OUTPUT_SOURCE_LINE (file, last_linenum);
3078 #else
3079 fprintf (file, "\t.ln\t%d\n",
3080 ((sdb_begin_function_line > -1)
3081 ? last_linenum - sdb_begin_function_line : 1));
3082 #endif
3084 #endif
3086 #if defined (DBX_DEBUGGING_INFO)
3087 if (write_symbols == DBX_DEBUG)
3088 dbxout_source_line (file, filename, NOTE_LINE_NUMBER (insn));
3089 #endif
3091 #if defined (XCOFF_DEBUGGING_INFO)
3092 if (write_symbols == XCOFF_DEBUG)
3093 xcoffout_source_line (file, filename, insn);
3094 #endif
3096 #ifdef DWARF_DEBUGGING_INFO
3097 if (write_symbols == DWARF_DEBUG)
3098 dwarfout_line (filename, NOTE_LINE_NUMBER (insn));
3099 #endif
3101 #ifdef DWARF2_DEBUGGING_INFO
3102 if (write_symbols == DWARF2_DEBUG)
3103 dwarf2out_line (filename, NOTE_LINE_NUMBER (insn));
3104 #endif
3108 /* For each operand in INSN, simplify (subreg (reg)) so that it refers
3109 directly to the desired hard register. */
3111 void
3112 cleanup_subreg_operands (insn)
3113 rtx insn;
3115 int i;
3116 extract_insn_cached (insn);
3117 for (i = 0; i < recog_data.n_operands; i++)
3119 if (GET_CODE (recog_data.operand[i]) == SUBREG)
3120 recog_data.operand[i] = alter_subreg (recog_data.operand[i]);
3121 else if (GET_CODE (recog_data.operand[i]) == PLUS
3122 || GET_CODE (recog_data.operand[i]) == MULT)
3123 recog_data.operand[i] = walk_alter_subreg (recog_data.operand[i]);
3126 for (i = 0; i < recog_data.n_dups; i++)
3128 if (GET_CODE (*recog_data.dup_loc[i]) == SUBREG)
3129 *recog_data.dup_loc[i] = alter_subreg (*recog_data.dup_loc[i]);
3130 else if (GET_CODE (*recog_data.dup_loc[i]) == PLUS
3131 || GET_CODE (*recog_data.dup_loc[i]) == MULT)
3132 *recog_data.dup_loc[i] = walk_alter_subreg (*recog_data.dup_loc[i]);
3136 /* If X is a SUBREG, replace it with a REG or a MEM,
3137 based on the thing it is a subreg of. */
3140 alter_subreg (x)
3141 register rtx x;
3143 register rtx y = SUBREG_REG (x);
3145 if (GET_CODE (y) == SUBREG)
3146 y = alter_subreg (y);
3148 /* If reload is operating, we may be replacing inside this SUBREG.
3149 Check for that and make a new one if so. */
3150 if (reload_in_progress && find_replacement (&SUBREG_REG (x)) != 0)
3151 x = copy_rtx (x);
3153 if (GET_CODE (y) == REG)
3155 int regno;
3156 /* If the word size is larger than the size of this register,
3157 adjust the register number to compensate. */
3158 /* ??? Note that this just catches stragglers created by/for
3159 integrate. It would be better if we either caught these
3160 earlier, or kept _all_ subregs until now and eliminate
3161 gen_lowpart and friends. */
3163 #ifdef ALTER_HARD_SUBREG
3164 regno = ALTER_HARD_SUBREG (GET_MODE (x), SUBREG_WORD (x),
3165 GET_MODE (y), REGNO (y));
3166 #else
3167 regno = REGNO (y) + SUBREG_WORD (x);
3168 #endif
3169 PUT_CODE (x, REG);
3170 REGNO (x) = regno;
3171 ORIGINAL_REGNO (x) = ORIGINAL_REGNO (y);
3172 /* This field has a different meaning for REGs and SUBREGs. Make sure
3173 to clear it! */
3174 x->used = 0;
3176 else if (GET_CODE (y) == MEM)
3178 register int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
3180 if (BYTES_BIG_ENDIAN)
3181 offset -= (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (x)))
3182 - MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (y))));
3183 PUT_CODE (x, MEM);
3184 MEM_COPY_ATTRIBUTES (x, y);
3185 XEXP (x, 0) = plus_constant (XEXP (y, 0), offset);
3188 return x;
3191 /* Do alter_subreg on all the SUBREGs contained in X. */
3193 static rtx
3194 walk_alter_subreg (x)
3195 rtx x;
3197 switch (GET_CODE (x))
3199 case PLUS:
3200 case MULT:
3201 XEXP (x, 0) = walk_alter_subreg (XEXP (x, 0));
3202 XEXP (x, 1) = walk_alter_subreg (XEXP (x, 1));
3203 break;
3205 case MEM:
3206 XEXP (x, 0) = walk_alter_subreg (XEXP (x, 0));
3207 break;
3209 case SUBREG:
3210 return alter_subreg (x);
3212 default:
3213 break;
3216 return x;
3219 #ifdef HAVE_cc0
3221 /* Given BODY, the body of a jump instruction, alter the jump condition
3222 as required by the bits that are set in cc_status.flags.
3223 Not all of the bits there can be handled at this level in all cases.
3225 The value is normally 0.
3226 1 means that the condition has become always true.
3227 -1 means that the condition has become always false.
3228 2 means that COND has been altered. */
3230 static int
3231 alter_cond (cond)
3232 register rtx cond;
3234 int value = 0;
3236 if (cc_status.flags & CC_REVERSED)
3238 value = 2;
3239 PUT_CODE (cond, swap_condition (GET_CODE (cond)));
3242 if (cc_status.flags & CC_INVERTED)
3244 value = 2;
3245 PUT_CODE (cond, reverse_condition (GET_CODE (cond)));
3248 if (cc_status.flags & CC_NOT_POSITIVE)
3249 switch (GET_CODE (cond))
3251 case LE:
3252 case LEU:
3253 case GEU:
3254 /* Jump becomes unconditional. */
3255 return 1;
3257 case GT:
3258 case GTU:
3259 case LTU:
3260 /* Jump becomes no-op. */
3261 return -1;
3263 case GE:
3264 PUT_CODE (cond, EQ);
3265 value = 2;
3266 break;
3268 case LT:
3269 PUT_CODE (cond, NE);
3270 value = 2;
3271 break;
3273 default:
3274 break;
3277 if (cc_status.flags & CC_NOT_NEGATIVE)
3278 switch (GET_CODE (cond))
3280 case GE:
3281 case GEU:
3282 /* Jump becomes unconditional. */
3283 return 1;
3285 case LT:
3286 case LTU:
3287 /* Jump becomes no-op. */
3288 return -1;
3290 case LE:
3291 case LEU:
3292 PUT_CODE (cond, EQ);
3293 value = 2;
3294 break;
3296 case GT:
3297 case GTU:
3298 PUT_CODE (cond, NE);
3299 value = 2;
3300 break;
3302 default:
3303 break;
3306 if (cc_status.flags & CC_NO_OVERFLOW)
3307 switch (GET_CODE (cond))
3309 case GEU:
3310 /* Jump becomes unconditional. */
3311 return 1;
3313 case LEU:
3314 PUT_CODE (cond, EQ);
3315 value = 2;
3316 break;
3318 case GTU:
3319 PUT_CODE (cond, NE);
3320 value = 2;
3321 break;
3323 case LTU:
3324 /* Jump becomes no-op. */
3325 return -1;
3327 default:
3328 break;
3331 if (cc_status.flags & (CC_Z_IN_NOT_N | CC_Z_IN_N))
3332 switch (GET_CODE (cond))
3334 default:
3335 abort ();
3337 case NE:
3338 PUT_CODE (cond, cc_status.flags & CC_Z_IN_N ? GE : LT);
3339 value = 2;
3340 break;
3342 case EQ:
3343 PUT_CODE (cond, cc_status.flags & CC_Z_IN_N ? LT : GE);
3344 value = 2;
3345 break;
3348 if (cc_status.flags & CC_NOT_SIGNED)
3349 /* The flags are valid if signed condition operators are converted
3350 to unsigned. */
3351 switch (GET_CODE (cond))
3353 case LE:
3354 PUT_CODE (cond, LEU);
3355 value = 2;
3356 break;
3358 case LT:
3359 PUT_CODE (cond, LTU);
3360 value = 2;
3361 break;
3363 case GT:
3364 PUT_CODE (cond, GTU);
3365 value = 2;
3366 break;
3368 case GE:
3369 PUT_CODE (cond, GEU);
3370 value = 2;
3371 break;
3373 default:
3374 break;
3377 return value;
3379 #endif
3381 /* Report inconsistency between the assembler template and the operands.
3382 In an `asm', it's the user's fault; otherwise, the compiler's fault. */
3384 void
3385 output_operand_lossage (msgid)
3386 const char *msgid;
3388 if (this_is_asm_operands)
3389 error_for_asm (this_is_asm_operands, "invalid `asm': %s", _(msgid));
3390 else
3392 error ("output_operand: %s", _(msgid));
3393 abort ();
3397 /* Output of assembler code from a template, and its subroutines. */
3399 /* Output text from TEMPLATE to the assembler output file,
3400 obeying %-directions to substitute operands taken from
3401 the vector OPERANDS.
3403 %N (for N a digit) means print operand N in usual manner.
3404 %lN means require operand N to be a CODE_LABEL or LABEL_REF
3405 and print the label name with no punctuation.
3406 %cN means require operand N to be a constant
3407 and print the constant expression with no punctuation.
3408 %aN means expect operand N to be a memory address
3409 (not a memory reference!) and print a reference
3410 to that address.
3411 %nN means expect operand N to be a constant
3412 and print a constant expression for minus the value
3413 of the operand, with no other punctuation. */
3415 static void
3416 output_asm_name ()
3418 if (flag_print_asm_name)
3420 /* Annotate the assembly with a comment describing the pattern and
3421 alternative used. */
3422 if (debug_insn)
3424 register int num = INSN_CODE (debug_insn);
3425 fprintf (asm_out_file, "\t%s %d\t%s",
3426 ASM_COMMENT_START, INSN_UID (debug_insn),
3427 insn_data[num].name);
3428 if (insn_data[num].n_alternatives > 1)
3429 fprintf (asm_out_file, "/%d", which_alternative + 1);
3430 #ifdef HAVE_ATTR_length
3431 fprintf (asm_out_file, "\t[length = %d]",
3432 get_attr_length (debug_insn));
3433 #endif
3434 /* Clear this so only the first assembler insn
3435 of any rtl insn will get the special comment for -dp. */
3436 debug_insn = 0;
3441 void
3442 output_asm_insn (template, operands)
3443 const char *template;
3444 rtx *operands;
3446 register const char *p;
3447 register int c;
3449 /* An insn may return a null string template
3450 in a case where no assembler code is needed. */
3451 if (*template == 0)
3452 return;
3454 p = template;
3455 putc ('\t', asm_out_file);
3457 #ifdef ASM_OUTPUT_OPCODE
3458 ASM_OUTPUT_OPCODE (asm_out_file, p);
3459 #endif
3461 while ((c = *p++))
3462 switch (c)
3464 case '\n':
3465 output_asm_name ();
3466 putc (c, asm_out_file);
3467 #ifdef ASM_OUTPUT_OPCODE
3468 while ((c = *p) == '\t')
3470 putc (c, asm_out_file);
3471 p++;
3473 ASM_OUTPUT_OPCODE (asm_out_file, p);
3474 #endif
3475 break;
3477 #ifdef ASSEMBLER_DIALECT
3478 case '{':
3480 register int i;
3482 /* If we want the first dialect, do nothing. Otherwise, skip
3483 DIALECT_NUMBER of strings ending with '|'. */
3484 for (i = 0; i < dialect_number; i++)
3486 while (*p && *p != '}' && *p++ != '|')
3488 if (*p == '}')
3489 break;
3490 if (*p == '|')
3491 p++;
3494 break;
3496 case '|':
3497 /* Skip to close brace. */
3498 while (*p && *p++ != '}')
3500 break;
3502 case '}':
3503 break;
3504 #endif
3506 case '%':
3507 /* %% outputs a single %. */
3508 if (*p == '%')
3510 p++;
3511 putc (c, asm_out_file);
3513 /* %= outputs a number which is unique to each insn in the entire
3514 compilation. This is useful for making local labels that are
3515 referred to more than once in a given insn. */
3516 else if (*p == '=')
3518 p++;
3519 fprintf (asm_out_file, "%d", insn_counter);
3521 /* % followed by a letter and some digits
3522 outputs an operand in a special way depending on the letter.
3523 Letters `acln' are implemented directly.
3524 Other letters are passed to `output_operand' so that
3525 the PRINT_OPERAND macro can define them. */
3526 else if (ISLOWER (*p) || ISUPPER (*p))
3528 int letter = *p++;
3529 c = atoi (p);
3531 if (! (*p >= '0' && *p <= '9'))
3532 output_operand_lossage ("operand number missing after %-letter");
3533 else if (this_is_asm_operands && (c < 0 || (unsigned int) c >= insn_noperands))
3534 output_operand_lossage ("operand number out of range");
3535 else if (letter == 'l')
3536 output_asm_label (operands[c]);
3537 else if (letter == 'a')
3538 output_address (operands[c]);
3539 else if (letter == 'c')
3541 if (CONSTANT_ADDRESS_P (operands[c]))
3542 output_addr_const (asm_out_file, operands[c]);
3543 else
3544 output_operand (operands[c], 'c');
3546 else if (letter == 'n')
3548 if (GET_CODE (operands[c]) == CONST_INT)
3549 fprintf (asm_out_file, HOST_WIDE_INT_PRINT_DEC,
3550 - INTVAL (operands[c]));
3551 else
3553 putc ('-', asm_out_file);
3554 output_addr_const (asm_out_file, operands[c]);
3557 else
3558 output_operand (operands[c], letter);
3560 while ((c = *p) >= '0' && c <= '9')
3561 p++;
3563 /* % followed by a digit outputs an operand the default way. */
3564 else if (*p >= '0' && *p <= '9')
3566 c = atoi (p);
3567 if (this_is_asm_operands
3568 && (c < 0 || (unsigned int) c >= insn_noperands))
3569 output_operand_lossage ("operand number out of range");
3570 else
3571 output_operand (operands[c], 0);
3572 while ((c = *p) >= '0' && c <= '9')
3573 p++;
3575 /* % followed by punctuation: output something for that
3576 punctuation character alone, with no operand.
3577 The PRINT_OPERAND macro decides what is actually done. */
3578 #ifdef PRINT_OPERAND_PUNCT_VALID_P
3579 else if (PRINT_OPERAND_PUNCT_VALID_P ((unsigned char) *p))
3580 output_operand (NULL_RTX, *p++);
3581 #endif
3582 else
3583 output_operand_lossage ("invalid %%-code");
3584 break;
3586 default:
3587 putc (c, asm_out_file);
3590 output_asm_name ();
3592 putc ('\n', asm_out_file);
3595 /* Output a LABEL_REF, or a bare CODE_LABEL, as an assembler symbol. */
3597 void
3598 output_asm_label (x)
3599 rtx x;
3601 char buf[256];
3603 if (GET_CODE (x) == LABEL_REF)
3604 x = XEXP (x, 0);
3605 if (GET_CODE (x) == CODE_LABEL
3606 || (GET_CODE (x) == NOTE
3607 && NOTE_LINE_NUMBER (x) == NOTE_INSN_DELETED_LABEL))
3608 ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
3609 else
3610 output_operand_lossage ("`%l' operand isn't a label");
3612 assemble_name (asm_out_file, buf);
3615 /* Print operand X using machine-dependent assembler syntax.
3616 The macro PRINT_OPERAND is defined just to control this function.
3617 CODE is a non-digit that preceded the operand-number in the % spec,
3618 such as 'z' if the spec was `%z3'. CODE is 0 if there was no char
3619 between the % and the digits.
3620 When CODE is a non-letter, X is 0.
3622 The meanings of the letters are machine-dependent and controlled
3623 by PRINT_OPERAND. */
3625 static void
3626 output_operand (x, code)
3627 rtx x;
3628 int code ATTRIBUTE_UNUSED;
3630 if (x && GET_CODE (x) == SUBREG)
3631 x = alter_subreg (x);
3633 /* If X is a pseudo-register, abort now rather than writing trash to the
3634 assembler file. */
3636 if (x && GET_CODE (x) == REG && REGNO (x) >= FIRST_PSEUDO_REGISTER)
3637 abort ();
3639 PRINT_OPERAND (asm_out_file, x, code);
3642 /* Print a memory reference operand for address X
3643 using machine-dependent assembler syntax.
3644 The macro PRINT_OPERAND_ADDRESS exists just to control this function. */
3646 void
3647 output_address (x)
3648 rtx x;
3650 walk_alter_subreg (x);
3651 PRINT_OPERAND_ADDRESS (asm_out_file, x);
3654 /* Print an integer constant expression in assembler syntax.
3655 Addition and subtraction are the only arithmetic
3656 that may appear in these expressions. */
3658 void
3659 output_addr_const (file, x)
3660 FILE *file;
3661 rtx x;
3663 char buf[256];
3665 restart:
3666 switch (GET_CODE (x))
3668 case PC:
3669 if (flag_pic)
3670 putc ('.', file);
3671 else
3672 abort ();
3673 break;
3675 case SYMBOL_REF:
3676 #ifdef ASM_OUTPUT_SYMBOL_REF
3677 ASM_OUTPUT_SYMBOL_REF (file, x);
3678 #else
3679 assemble_name (file, XSTR (x, 0));
3680 #endif
3681 break;
3683 case LABEL_REF:
3684 x = XEXP (x, 0);
3685 /* Fall through. */
3686 case CODE_LABEL:
3687 ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
3688 assemble_name (file, buf);
3689 break;
3691 case CONST_INT:
3692 fprintf (file, HOST_WIDE_INT_PRINT_DEC, INTVAL (x));
3693 break;
3695 case CONST:
3696 /* This used to output parentheses around the expression,
3697 but that does not work on the 386 (either ATT or BSD assembler). */
3698 output_addr_const (file, XEXP (x, 0));
3699 break;
3701 case CONST_DOUBLE:
3702 if (GET_MODE (x) == VOIDmode)
3704 /* We can use %d if the number is one word and positive. */
3705 if (CONST_DOUBLE_HIGH (x))
3706 fprintf (file, HOST_WIDE_INT_PRINT_DOUBLE_HEX,
3707 CONST_DOUBLE_HIGH (x), CONST_DOUBLE_LOW (x));
3708 else if (CONST_DOUBLE_LOW (x) < 0)
3709 fprintf (file, HOST_WIDE_INT_PRINT_HEX, CONST_DOUBLE_LOW (x));
3710 else
3711 fprintf (file, HOST_WIDE_INT_PRINT_DEC, CONST_DOUBLE_LOW (x));
3713 else
3714 /* We can't handle floating point constants;
3715 PRINT_OPERAND must handle them. */
3716 output_operand_lossage ("floating constant misused");
3717 break;
3719 case PLUS:
3720 /* Some assemblers need integer constants to appear last (eg masm). */
3721 if (GET_CODE (XEXP (x, 0)) == CONST_INT)
3723 output_addr_const (file, XEXP (x, 1));
3724 if (INTVAL (XEXP (x, 0)) >= 0)
3725 fprintf (file, "+");
3726 output_addr_const (file, XEXP (x, 0));
3728 else
3730 output_addr_const (file, XEXP (x, 0));
3731 if (GET_CODE (XEXP (x, 1)) != CONST_INT
3732 || INTVAL (XEXP (x, 1)) >= 0)
3733 fprintf (file, "+");
3734 output_addr_const (file, XEXP (x, 1));
3736 break;
3738 case MINUS:
3739 /* Avoid outputting things like x-x or x+5-x,
3740 since some assemblers can't handle that. */
3741 x = simplify_subtraction (x);
3742 if (GET_CODE (x) != MINUS)
3743 goto restart;
3745 output_addr_const (file, XEXP (x, 0));
3746 fprintf (file, "-");
3747 if ((GET_CODE (XEXP (x, 1)) == CONST_INT
3748 && INTVAL (XEXP (x, 1)) < 0)
3749 || GET_CODE (XEXP (x, 1)) != CONST_INT)
3751 fprintf (file, "%s", ASM_OPEN_PAREN);
3752 output_addr_const (file, XEXP (x, 1));
3753 fprintf (file, "%s", ASM_CLOSE_PAREN);
3755 else
3756 output_addr_const (file, XEXP (x, 1));
3757 break;
3759 case ZERO_EXTEND:
3760 case SIGN_EXTEND:
3761 output_addr_const (file, XEXP (x, 0));
3762 break;
3764 default:
3765 #ifdef OUTPUT_ADDR_CONST_EXTRA
3766 OUTPUT_ADDR_CONST_EXTRA (file, x, fail);
3767 break;
3769 fail:
3770 #endif
3771 output_operand_lossage ("invalid expression as operand");
3775 /* A poor man's fprintf, with the added features of %I, %R, %L, and %U.
3776 %R prints the value of REGISTER_PREFIX.
3777 %L prints the value of LOCAL_LABEL_PREFIX.
3778 %U prints the value of USER_LABEL_PREFIX.
3779 %I prints the value of IMMEDIATE_PREFIX.
3780 %O runs ASM_OUTPUT_OPCODE to transform what follows in the string.
3781 Also supported are %d, %x, %s, %e, %f, %g and %%.
3783 We handle alternate assembler dialects here, just like output_asm_insn. */
3785 void
3786 asm_fprintf VPARAMS ((FILE *file, const char *p, ...))
3788 #ifndef ANSI_PROTOTYPES
3789 FILE *file;
3790 const char *p;
3791 #endif
3792 va_list argptr;
3793 char buf[10];
3794 char *q, c;
3796 VA_START (argptr, p);
3798 #ifndef ANSI_PROTOTYPES
3799 file = va_arg (argptr, FILE *);
3800 p = va_arg (argptr, const char *);
3801 #endif
3803 buf[0] = '%';
3805 while ((c = *p++))
3806 switch (c)
3808 #ifdef ASSEMBLER_DIALECT
3809 case '{':
3811 int i;
3813 /* If we want the first dialect, do nothing. Otherwise, skip
3814 DIALECT_NUMBER of strings ending with '|'. */
3815 for (i = 0; i < dialect_number; i++)
3817 while (*p && *p++ != '|')
3820 if (*p == '|')
3821 p++;
3824 break;
3826 case '|':
3827 /* Skip to close brace. */
3828 while (*p && *p++ != '}')
3830 break;
3832 case '}':
3833 break;
3834 #endif
3836 case '%':
3837 c = *p++;
3838 q = &buf[1];
3839 while ((c >= '0' && c <= '9') || c == '.')
3841 *q++ = c;
3842 c = *p++;
3844 switch (c)
3846 case '%':
3847 fprintf (file, "%%");
3848 break;
3850 case 'd': case 'i': case 'u':
3851 case 'x': case 'p': case 'X':
3852 case 'o':
3853 *q++ = c;
3854 *q = 0;
3855 fprintf (file, buf, va_arg (argptr, int));
3856 break;
3858 case 'w':
3859 /* This is a prefix to the 'd', 'i', 'u', 'x', 'p', and 'X' cases,
3860 but we do not check for those cases. It means that the value
3861 is a HOST_WIDE_INT, which may be either `int' or `long'. */
3863 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
3864 #else
3865 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
3866 *q++ = 'l';
3867 #else
3868 *q++ = 'l';
3869 *q++ = 'l';
3870 #endif
3871 #endif
3873 *q++ = *p++;
3874 *q = 0;
3875 fprintf (file, buf, va_arg (argptr, HOST_WIDE_INT));
3876 break;
3878 case 'l':
3879 *q++ = c;
3880 *q++ = *p++;
3881 *q = 0;
3882 fprintf (file, buf, va_arg (argptr, long));
3883 break;
3885 case 'e':
3886 case 'f':
3887 case 'g':
3888 *q++ = c;
3889 *q = 0;
3890 fprintf (file, buf, va_arg (argptr, double));
3891 break;
3893 case 's':
3894 *q++ = c;
3895 *q = 0;
3896 fprintf (file, buf, va_arg (argptr, char *));
3897 break;
3899 case 'O':
3900 #ifdef ASM_OUTPUT_OPCODE
3901 ASM_OUTPUT_OPCODE (asm_out_file, p);
3902 #endif
3903 break;
3905 case 'R':
3906 #ifdef REGISTER_PREFIX
3907 fprintf (file, "%s", REGISTER_PREFIX);
3908 #endif
3909 break;
3911 case 'I':
3912 #ifdef IMMEDIATE_PREFIX
3913 fprintf (file, "%s", IMMEDIATE_PREFIX);
3914 #endif
3915 break;
3917 case 'L':
3918 #ifdef LOCAL_LABEL_PREFIX
3919 fprintf (file, "%s", LOCAL_LABEL_PREFIX);
3920 #endif
3921 break;
3923 case 'U':
3924 fputs (user_label_prefix, file);
3925 break;
3927 #ifdef ASM_FPRINTF_EXTENSIONS
3928 /* Upper case letters are reserved for general use by asm_fprintf
3929 and so are not available to target specific code. In order to
3930 prevent the ASM_FPRINTF_EXTENSIONS macro from using them then,
3931 they are defined here. As they get turned into real extensions
3932 to asm_fprintf they should be removed from this list. */
3933 case 'A': case 'B': case 'C': case 'D': case 'E':
3934 case 'F': case 'G': case 'H': case 'J': case 'K':
3935 case 'M': case 'N': case 'P': case 'Q': case 'S':
3936 case 'T': case 'V': case 'W': case 'Y': case 'Z':
3937 break;
3939 ASM_FPRINTF_EXTENSIONS (file, argptr, p)
3940 #endif
3941 default:
3942 abort ();
3944 break;
3946 default:
3947 fputc (c, file);
3949 va_end (argptr);
3952 /* Split up a CONST_DOUBLE or integer constant rtx
3953 into two rtx's for single words,
3954 storing in *FIRST the word that comes first in memory in the target
3955 and in *SECOND the other. */
3957 void
3958 split_double (value, first, second)
3959 rtx value;
3960 rtx *first, *second;
3962 if (GET_CODE (value) == CONST_INT)
3964 if (HOST_BITS_PER_WIDE_INT >= (2 * BITS_PER_WORD))
3966 /* In this case the CONST_INT holds both target words.
3967 Extract the bits from it into two word-sized pieces.
3968 Sign extend each half to HOST_WIDE_INT. */
3969 unsigned HOST_WIDE_INT low, high;
3970 unsigned HOST_WIDE_INT mask, sign_bit, sign_extend;
3972 /* Set sign_bit to the most significant bit of a word. */
3973 sign_bit = 1;
3974 sign_bit <<= BITS_PER_WORD - 1;
3976 /* Set mask so that all bits of the word are set. We could
3977 have used 1 << BITS_PER_WORD instead of basing the
3978 calculation on sign_bit. However, on machines where
3979 HOST_BITS_PER_WIDE_INT == BITS_PER_WORD, it could cause a
3980 compiler warning, even though the code would never be
3981 executed. */
3982 mask = sign_bit << 1;
3983 mask--;
3985 /* Set sign_extend as any remaining bits. */
3986 sign_extend = ~mask;
3988 /* Pick the lower word and sign-extend it. */
3989 low = INTVAL (value);
3990 low &= mask;
3991 if (low & sign_bit)
3992 low |= sign_extend;
3994 /* Pick the higher word, shifted to the least significant
3995 bits, and sign-extend it. */
3996 high = INTVAL (value);
3997 high >>= BITS_PER_WORD - 1;
3998 high >>= 1;
3999 high &= mask;
4000 if (high & sign_bit)
4001 high |= sign_extend;
4003 /* Store the words in the target machine order. */
4004 if (WORDS_BIG_ENDIAN)
4006 *first = GEN_INT (high);
4007 *second = GEN_INT (low);
4009 else
4011 *first = GEN_INT (low);
4012 *second = GEN_INT (high);
4015 else
4017 /* The rule for using CONST_INT for a wider mode
4018 is that we regard the value as signed.
4019 So sign-extend it. */
4020 rtx high = (INTVAL (value) < 0 ? constm1_rtx : const0_rtx);
4021 if (WORDS_BIG_ENDIAN)
4023 *first = high;
4024 *second = value;
4026 else
4028 *first = value;
4029 *second = high;
4033 else if (GET_CODE (value) != CONST_DOUBLE)
4035 if (WORDS_BIG_ENDIAN)
4037 *first = const0_rtx;
4038 *second = value;
4040 else
4042 *first = value;
4043 *second = const0_rtx;
4046 else if (GET_MODE (value) == VOIDmode
4047 /* This is the old way we did CONST_DOUBLE integers. */
4048 || GET_MODE_CLASS (GET_MODE (value)) == MODE_INT)
4050 /* In an integer, the words are defined as most and least significant.
4051 So order them by the target's convention. */
4052 if (WORDS_BIG_ENDIAN)
4054 *first = GEN_INT (CONST_DOUBLE_HIGH (value));
4055 *second = GEN_INT (CONST_DOUBLE_LOW (value));
4057 else
4059 *first = GEN_INT (CONST_DOUBLE_LOW (value));
4060 *second = GEN_INT (CONST_DOUBLE_HIGH (value));
4063 else
4065 #ifdef REAL_ARITHMETIC
4066 REAL_VALUE_TYPE r;
4067 long l[2];
4068 REAL_VALUE_FROM_CONST_DOUBLE (r, value);
4070 /* Note, this converts the REAL_VALUE_TYPE to the target's
4071 format, splits up the floating point double and outputs
4072 exactly 32 bits of it into each of l[0] and l[1] --
4073 not necessarily BITS_PER_WORD bits. */
4074 REAL_VALUE_TO_TARGET_DOUBLE (r, l);
4076 /* If 32 bits is an entire word for the target, but not for the host,
4077 then sign-extend on the host so that the number will look the same
4078 way on the host that it would on the target. See for instance
4079 simplify_unary_operation. The #if is needed to avoid compiler
4080 warnings. */
4082 #if HOST_BITS_PER_LONG > 32
4083 if (BITS_PER_WORD < HOST_BITS_PER_LONG && BITS_PER_WORD == 32)
4085 if (l[0] & ((long) 1 << 31))
4086 l[0] |= ((long) (-1) << 32);
4087 if (l[1] & ((long) 1 << 31))
4088 l[1] |= ((long) (-1) << 32);
4090 #endif
4092 *first = GEN_INT ((HOST_WIDE_INT) l[0]);
4093 *second = GEN_INT ((HOST_WIDE_INT) l[1]);
4094 #else
4095 if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
4096 || HOST_BITS_PER_WIDE_INT != BITS_PER_WORD)
4097 && ! flag_pretend_float)
4098 abort ();
4100 if (
4101 #ifdef HOST_WORDS_BIG_ENDIAN
4102 WORDS_BIG_ENDIAN
4103 #else
4104 ! WORDS_BIG_ENDIAN
4105 #endif
4108 /* Host and target agree => no need to swap. */
4109 *first = GEN_INT (CONST_DOUBLE_LOW (value));
4110 *second = GEN_INT (CONST_DOUBLE_HIGH (value));
4112 else
4114 *second = GEN_INT (CONST_DOUBLE_LOW (value));
4115 *first = GEN_INT (CONST_DOUBLE_HIGH (value));
4117 #endif /* no REAL_ARITHMETIC */
4121 /* Return nonzero if this function has no function calls. */
4124 leaf_function_p ()
4126 rtx insn;
4127 rtx link;
4129 if (profile_flag || profile_block_flag || profile_arc_flag)
4130 return 0;
4132 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4134 if (GET_CODE (insn) == CALL_INSN
4135 && ! SIBLING_CALL_P (insn))
4136 return 0;
4137 if (GET_CODE (insn) == INSN
4138 && GET_CODE (PATTERN (insn)) == SEQUENCE
4139 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == CALL_INSN
4140 && ! SIBLING_CALL_P (XVECEXP (PATTERN (insn), 0, 0)))
4141 return 0;
4143 for (link = current_function_epilogue_delay_list;
4144 link;
4145 link = XEXP (link, 1))
4147 insn = XEXP (link, 0);
4149 if (GET_CODE (insn) == CALL_INSN
4150 && ! SIBLING_CALL_P (insn))
4151 return 0;
4152 if (GET_CODE (insn) == INSN
4153 && GET_CODE (PATTERN (insn)) == SEQUENCE
4154 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == CALL_INSN
4155 && ! SIBLING_CALL_P (XVECEXP (PATTERN (insn), 0, 0)))
4156 return 0;
4159 return 1;
4162 /* On some machines, a function with no call insns
4163 can run faster if it doesn't create its own register window.
4164 When output, the leaf function should use only the "output"
4165 registers. Ordinarily, the function would be compiled to use
4166 the "input" registers to find its arguments; it is a candidate
4167 for leaf treatment if it uses only the "input" registers.
4168 Leaf function treatment means renumbering so the function
4169 uses the "output" registers instead. */
4171 #ifdef LEAF_REGISTERS
4173 /* Return 1 if this function uses only the registers that can be
4174 safely renumbered. */
4177 only_leaf_regs_used ()
4179 int i;
4180 char *permitted_reg_in_leaf_functions = LEAF_REGISTERS;
4182 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
4183 if ((regs_ever_live[i] || global_regs[i])
4184 && ! permitted_reg_in_leaf_functions[i])
4185 return 0;
4187 if (current_function_uses_pic_offset_table
4188 && pic_offset_table_rtx != 0
4189 && GET_CODE (pic_offset_table_rtx) == REG
4190 && ! permitted_reg_in_leaf_functions[REGNO (pic_offset_table_rtx)])
4191 return 0;
4193 return 1;
4196 /* Scan all instructions and renumber all registers into those
4197 available in leaf functions. */
4199 static void
4200 leaf_renumber_regs (first)
4201 rtx first;
4203 rtx insn;
4205 /* Renumber only the actual patterns.
4206 The reg-notes can contain frame pointer refs,
4207 and renumbering them could crash, and should not be needed. */
4208 for (insn = first; insn; insn = NEXT_INSN (insn))
4209 if (INSN_P (insn))
4210 leaf_renumber_regs_insn (PATTERN (insn));
4211 for (insn = current_function_epilogue_delay_list;
4212 insn;
4213 insn = XEXP (insn, 1))
4214 if (INSN_P (XEXP (insn, 0)))
4215 leaf_renumber_regs_insn (PATTERN (XEXP (insn, 0)));
4218 /* Scan IN_RTX and its subexpressions, and renumber all regs into those
4219 available in leaf functions. */
4221 void
4222 leaf_renumber_regs_insn (in_rtx)
4223 register rtx in_rtx;
4225 register int i, j;
4226 register const char *format_ptr;
4228 if (in_rtx == 0)
4229 return;
4231 /* Renumber all input-registers into output-registers.
4232 renumbered_regs would be 1 for an output-register;
4233 they */
4235 if (GET_CODE (in_rtx) == REG)
4237 int newreg;
4239 /* Don't renumber the same reg twice. */
4240 if (in_rtx->used)
4241 return;
4243 newreg = REGNO (in_rtx);
4244 /* Don't try to renumber pseudo regs. It is possible for a pseudo reg
4245 to reach here as part of a REG_NOTE. */
4246 if (newreg >= FIRST_PSEUDO_REGISTER)
4248 in_rtx->used = 1;
4249 return;
4251 newreg = LEAF_REG_REMAP (newreg);
4252 if (newreg < 0)
4253 abort ();
4254 regs_ever_live[REGNO (in_rtx)] = 0;
4255 regs_ever_live[newreg] = 1;
4256 REGNO (in_rtx) = newreg;
4257 in_rtx->used = 1;
4260 if (INSN_P (in_rtx))
4262 /* Inside a SEQUENCE, we find insns.
4263 Renumber just the patterns of these insns,
4264 just as we do for the top-level insns. */
4265 leaf_renumber_regs_insn (PATTERN (in_rtx));
4266 return;
4269 format_ptr = GET_RTX_FORMAT (GET_CODE (in_rtx));
4271 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (in_rtx)); i++)
4272 switch (*format_ptr++)
4274 case 'e':
4275 leaf_renumber_regs_insn (XEXP (in_rtx, i));
4276 break;
4278 case 'E':
4279 if (NULL != XVEC (in_rtx, i))
4281 for (j = 0; j < XVECLEN (in_rtx, i); j++)
4282 leaf_renumber_regs_insn (XVECEXP (in_rtx, i, j));
4284 break;
4286 case 'S':
4287 case 's':
4288 case '0':
4289 case 'i':
4290 case 'w':
4291 case 'n':
4292 case 'u':
4293 break;
4295 default:
4296 abort ();
4299 #endif