Daily bump.
[official-gcc.git] / gcc / final.c
blob5f8de3035316d040b73d5db1996bdc12a1b4ece3
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, 2002 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 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 in assembler by the target functions 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-attr.h"
56 #include "recog.h"
57 #include "conditions.h"
58 #include "flags.h"
59 #include "real.h"
60 #include "hard-reg-set.h"
61 #include "output.h"
62 #include "except.h"
63 #include "function.h"
64 #include "toplev.h"
65 #include "reload.h"
66 #include "intl.h"
67 #include "basic-block.h"
68 #include "target.h"
69 #include "debug.h"
70 #include "expr.h"
72 #ifdef XCOFF_DEBUGGING_INFO
73 #include "xcoffout.h" /* Needed for external data
74 declarations for e.g. AIX 4.x. */
75 #endif
77 #if defined (DWARF2_UNWIND_INFO) || defined (DWARF2_DEBUGGING_INFO)
78 #include "dwarf2out.h"
79 #endif
81 /* If we aren't using cc0, CC_STATUS_INIT shouldn't exist. So define a
82 null default for it to save conditionalization later. */
83 #ifndef CC_STATUS_INIT
84 #define CC_STATUS_INIT
85 #endif
87 /* How to start an assembler comment. */
88 #ifndef ASM_COMMENT_START
89 #define ASM_COMMENT_START ";#"
90 #endif
92 /* Is the given character a logical line separator for the assembler? */
93 #ifndef IS_ASM_LOGICAL_LINE_SEPARATOR
94 #define IS_ASM_LOGICAL_LINE_SEPARATOR(C) ((C) == ';')
95 #endif
97 #ifndef JUMP_TABLES_IN_TEXT_SECTION
98 #define JUMP_TABLES_IN_TEXT_SECTION 0
99 #endif
101 /* Last insn processed by final_scan_insn. */
102 static rtx debug_insn;
103 rtx current_output_insn;
105 /* Line number of last NOTE. */
106 static int last_linenum;
108 /* Highest line number in current block. */
109 static int high_block_linenum;
111 /* Likewise for function. */
112 static int high_function_linenum;
114 /* Filename of last NOTE. */
115 static const char *last_filename;
117 /* Number of instrumented arcs when profile_arc_flag is set. */
118 extern int count_instrumented_edges;
120 extern int length_unit_log; /* This is defined in insn-attrtab.c. */
122 /* Nonzero while outputting an `asm' with operands.
123 This means that inconsistencies are the user's fault, so don't abort.
124 The precise value is the insn being output, to pass to error_for_asm. */
125 static rtx this_is_asm_operands;
127 /* Number of operands of this insn, for an `asm' with operands. */
128 static unsigned int insn_noperands;
130 /* Compare optimization flag. */
132 static rtx last_ignored_compare = 0;
134 /* Flag indicating this insn is the start of a new basic block. */
136 static int new_block = 1;
138 /* Assign a unique number to each insn that is output.
139 This can be used to generate unique local labels. */
141 static int insn_counter = 0;
143 #ifdef HAVE_cc0
144 /* This variable contains machine-dependent flags (defined in tm.h)
145 set and examined by output routines
146 that describe how to interpret the condition codes properly. */
148 CC_STATUS cc_status;
150 /* During output of an insn, this contains a copy of cc_status
151 from before the insn. */
153 CC_STATUS cc_prev_status;
154 #endif
156 /* Indexed by hardware reg number, is 1 if that register is ever
157 used in the current function.
159 In life_analysis, or in stupid_life_analysis, this is set
160 up to record the hard regs used explicitly. Reload adds
161 in the hard regs used for holding pseudo regs. Final uses
162 it to generate the code in the function prologue and epilogue
163 to save and restore registers as needed. */
165 char regs_ever_live[FIRST_PSEUDO_REGISTER];
167 /* Nonzero means current function must be given a frame pointer.
168 Set in stmt.c if anything is allocated on the stack there.
169 Set in reload1.c if anything is allocated on the stack there. */
171 int frame_pointer_needed;
173 /* Assign unique numbers to labels generated for profiling. */
175 int profile_label_no;
177 /* Number of unmatched NOTE_INSN_BLOCK_BEG notes we have seen. */
179 static int block_depth;
181 /* Nonzero if have enabled APP processing of our assembler output. */
183 static int app_on;
185 /* If we are outputting an insn sequence, this contains the sequence rtx.
186 Zero otherwise. */
188 rtx final_sequence;
190 #ifdef ASSEMBLER_DIALECT
192 /* Number of the assembler dialect to use, starting at 0. */
193 static int dialect_number;
194 #endif
196 /* Indexed by line number, nonzero if there is a note for that line. */
198 static char *line_note_exists;
200 #ifdef HAVE_conditional_execution
201 /* Nonnull if the insn currently being emitted was a COND_EXEC pattern. */
202 rtx current_insn_predicate;
203 #endif
205 #ifdef HAVE_ATTR_length
206 static int asm_insn_count PARAMS ((rtx));
207 #endif
208 static void profile_function PARAMS ((FILE *));
209 static void profile_after_prologue PARAMS ((FILE *));
210 static void notice_source_line PARAMS ((rtx));
211 static rtx walk_alter_subreg PARAMS ((rtx *));
212 static void output_asm_name PARAMS ((void));
213 static tree get_mem_expr_from_op PARAMS ((rtx, int *));
214 static void output_asm_operand_names PARAMS ((rtx *, int *, int));
215 static void output_operand PARAMS ((rtx, int));
216 #ifdef LEAF_REGISTERS
217 static void leaf_renumber_regs PARAMS ((rtx));
218 #endif
219 #ifdef HAVE_cc0
220 static int alter_cond PARAMS ((rtx));
221 #endif
222 #ifndef ADDR_VEC_ALIGN
223 static int final_addr_vec_align PARAMS ((rtx));
224 #endif
225 #ifdef HAVE_ATTR_length
226 static int align_fuzz PARAMS ((rtx, rtx, int, unsigned));
227 #endif
229 /* Initialize data in final at the beginning of a compilation. */
231 void
232 init_final (filename)
233 const char *filename ATTRIBUTE_UNUSED;
235 app_on = 0;
236 final_sequence = 0;
238 #ifdef ASSEMBLER_DIALECT
239 dialect_number = ASSEMBLER_DIALECT;
240 #endif
243 /* Called at end of source file,
244 to output the block-profiling table for this entire compilation. */
246 void
247 end_final (filename)
248 const char *filename;
250 if (profile_arc_flag)
252 char name[20];
253 int align = exact_log2 (BIGGEST_ALIGNMENT / BITS_PER_UNIT);
254 int size, rounded;
255 int long_bytes = LONG_TYPE_SIZE / BITS_PER_UNIT;
256 int gcov_type_bytes = GCOV_TYPE_SIZE / BITS_PER_UNIT;
257 int pointer_bytes = POINTER_SIZE / BITS_PER_UNIT;
258 unsigned int align2 = LONG_TYPE_SIZE;
260 size = gcov_type_bytes * count_instrumented_edges;
261 rounded = size;
263 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
264 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
265 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
267 /* ??? This _really_ ought to be done with a structure layout
268 and with assemble_constructor. If long_bytes != pointer_bytes
269 we'll be emitting unaligned data at some point. */
270 if (long_bytes != pointer_bytes)
271 abort ();
273 data_section ();
275 /* Output the main header, of 11 words:
276 0: 1 if this file is initialized, else 0.
277 1: address of file name (LPBX1).
278 2: address of table of counts (LPBX2).
279 3: number of counts in the table.
280 4: always 0, for compatibility with Sun.
282 The following are GNU extensions:
284 5: address of table of start addrs of basic blocks (LPBX3).
285 6: Number of bytes in this header.
286 7: address of table of function names (LPBX4).
287 8: address of table of line numbers (LPBX5) or 0.
288 9: address of table of file names (LPBX6) or 0.
289 10: space reserved for basic block profiling. */
291 ASM_OUTPUT_ALIGN (asm_out_file, align);
293 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 0);
295 /* Zero word. */
296 assemble_integer (const0_rtx, long_bytes, align2, 1);
298 /* Address of filename. */
299 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 1);
300 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name), pointer_bytes,
301 align2, 1);
303 /* Address of count table. */
304 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 2);
305 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name), pointer_bytes,
306 align2, 1);
308 /* Count of the # of instrumented arcs. */
309 assemble_integer (GEN_INT (count_instrumented_edges),
310 long_bytes, align2, 1);
312 /* Zero word (link field). */
313 assemble_integer (const0_rtx, pointer_bytes, align2, 1);
315 assemble_integer (const0_rtx, pointer_bytes, align2, 1);
317 /* Byte count for extended structure. */
318 assemble_integer (GEN_INT (11 * UNITS_PER_WORD), long_bytes, align2, 1);
320 /* Address of function name table. */
321 assemble_integer (const0_rtx, pointer_bytes, align2, 1);
323 /* Address of line number and filename tables if debugging. */
324 assemble_integer (const0_rtx, pointer_bytes, align2, 1);
325 assemble_integer (const0_rtx, pointer_bytes, align2, 1);
327 /* Space for extension ptr (link field). */
328 assemble_integer (const0_rtx, UNITS_PER_WORD, align2, 1);
330 /* Output the file name changing the suffix to .d for
331 Sun tcov compatibility. */
332 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 1);
334 char *cwd = getpwd ();
335 int len = strlen (filename) + strlen (cwd) + 1;
336 char *data_file = (char *) alloca (len + 4);
338 strcpy (data_file, cwd);
339 strcat (data_file, "/");
340 strcat (data_file, filename);
341 strip_off_ending (data_file, len);
342 strcat (data_file, ".da");
343 assemble_string (data_file, strlen (data_file) + 1);
346 /* Make space for the table of counts. */
347 if (size == 0)
349 /* Realign data section. */
350 ASM_OUTPUT_ALIGN (asm_out_file, align);
351 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 2);
352 if (size != 0)
353 assemble_zeros (size);
355 else
357 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 2);
358 #ifdef ASM_OUTPUT_SHARED_LOCAL
359 if (flag_shared_data)
360 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
361 else
362 #endif
363 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
364 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name,
365 size, BIGGEST_ALIGNMENT);
366 #else
367 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
368 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size,
369 BIGGEST_ALIGNMENT);
370 #else
371 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
372 #endif
373 #endif
378 /* Default target function prologue and epilogue assembler output.
380 If not overridden for epilogue code, then the function body itself
381 contains return instructions wherever needed. */
382 void
383 default_function_pro_epilogue (file, size)
384 FILE *file ATTRIBUTE_UNUSED;
385 HOST_WIDE_INT size ATTRIBUTE_UNUSED;
389 /* Default target hook that outputs nothing to a stream. */
390 void
391 no_asm_to_stream (file)
392 FILE *file ATTRIBUTE_UNUSED;
396 /* Enable APP processing of subsequent output.
397 Used before the output from an `asm' statement. */
399 void
400 app_enable ()
402 if (! app_on)
404 fputs (ASM_APP_ON, asm_out_file);
405 app_on = 1;
409 /* Disable APP processing of subsequent output.
410 Called from varasm.c before most kinds of output. */
412 void
413 app_disable ()
415 if (app_on)
417 fputs (ASM_APP_OFF, asm_out_file);
418 app_on = 0;
422 /* Return the number of slots filled in the current
423 delayed branch sequence (we don't count the insn needing the
424 delay slot). Zero if not in a delayed branch sequence. */
426 #ifdef DELAY_SLOTS
428 dbr_sequence_length ()
430 if (final_sequence != 0)
431 return XVECLEN (final_sequence, 0) - 1;
432 else
433 return 0;
435 #endif
437 /* The next two pages contain routines used to compute the length of an insn
438 and to shorten branches. */
440 /* Arrays for insn lengths, and addresses. The latter is referenced by
441 `insn_current_length'. */
443 static int *insn_lengths;
445 #ifdef HAVE_ATTR_length
446 varray_type insn_addresses_;
447 #endif
449 /* Max uid for which the above arrays are valid. */
450 static int insn_lengths_max_uid;
452 /* Address of insn being processed. Used by `insn_current_length'. */
453 int insn_current_address;
455 /* Address of insn being processed in previous iteration. */
456 int insn_last_address;
458 /* known invariant alignment of insn being processed. */
459 int insn_current_align;
461 /* After shorten_branches, for any insn, uid_align[INSN_UID (insn)]
462 gives the next following alignment insn that increases the known
463 alignment, or NULL_RTX if there is no such insn.
464 For any alignment obtained this way, we can again index uid_align with
465 its uid to obtain the next following align that in turn increases the
466 alignment, till we reach NULL_RTX; the sequence obtained this way
467 for each insn we'll call the alignment chain of this insn in the following
468 comments. */
470 struct label_alignment
472 short alignment;
473 short max_skip;
476 static rtx *uid_align;
477 static int *uid_shuid;
478 static struct label_alignment *label_align;
480 /* Indicate that branch shortening hasn't yet been done. */
482 void
483 init_insn_lengths ()
485 if (uid_shuid)
487 free (uid_shuid);
488 uid_shuid = 0;
490 if (insn_lengths)
492 free (insn_lengths);
493 insn_lengths = 0;
494 insn_lengths_max_uid = 0;
496 #ifdef HAVE_ATTR_length
497 INSN_ADDRESSES_FREE ();
498 #endif
499 if (uid_align)
501 free (uid_align);
502 uid_align = 0;
506 /* Obtain the current length of an insn. If branch shortening has been done,
507 get its actual length. Otherwise, get its maximum length. */
510 get_attr_length (insn)
511 rtx insn ATTRIBUTE_UNUSED;
513 #ifdef HAVE_ATTR_length
514 rtx body;
515 int i;
516 int length = 0;
518 if (insn_lengths_max_uid > INSN_UID (insn))
519 return insn_lengths[INSN_UID (insn)];
520 else
521 switch (GET_CODE (insn))
523 case NOTE:
524 case BARRIER:
525 case CODE_LABEL:
526 return 0;
528 case CALL_INSN:
529 length = insn_default_length (insn);
530 break;
532 case JUMP_INSN:
533 body = PATTERN (insn);
534 if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
536 /* Alignment is machine-dependent and should be handled by
537 ADDR_VEC_ALIGN. */
539 else
540 length = insn_default_length (insn);
541 break;
543 case INSN:
544 body = PATTERN (insn);
545 if (GET_CODE (body) == USE || GET_CODE (body) == CLOBBER)
546 return 0;
548 else if (GET_CODE (body) == ASM_INPUT || asm_noperands (body) >= 0)
549 length = asm_insn_count (body) * insn_default_length (insn);
550 else if (GET_CODE (body) == SEQUENCE)
551 for (i = 0; i < XVECLEN (body, 0); i++)
552 length += get_attr_length (XVECEXP (body, 0, i));
553 else
554 length = insn_default_length (insn);
555 break;
557 default:
558 break;
561 #ifdef ADJUST_INSN_LENGTH
562 ADJUST_INSN_LENGTH (insn, length);
563 #endif
564 return length;
565 #else /* not HAVE_ATTR_length */
566 return 0;
567 #endif /* not HAVE_ATTR_length */
570 /* Code to handle alignment inside shorten_branches. */
572 /* Here is an explanation how the algorithm in align_fuzz can give
573 proper results:
575 Call a sequence of instructions beginning with alignment point X
576 and continuing until the next alignment point `block X'. When `X'
577 is used in an expression, it means the alignment value of the
578 alignment point.
580 Call the distance between the start of the first insn of block X, and
581 the end of the last insn of block X `IX', for the `inner size of X'.
582 This is clearly the sum of the instruction lengths.
584 Likewise with the next alignment-delimited block following X, which we
585 shall call block Y.
587 Call the distance between the start of the first insn of block X, and
588 the start of the first insn of block Y `OX', for the `outer size of X'.
590 The estimated padding is then OX - IX.
592 OX can be safely estimated as
594 if (X >= Y)
595 OX = round_up(IX, Y)
596 else
597 OX = round_up(IX, X) + Y - X
599 Clearly est(IX) >= real(IX), because that only depends on the
600 instruction lengths, and those being overestimated is a given.
602 Clearly round_up(foo, Z) >= round_up(bar, Z) if foo >= bar, so
603 we needn't worry about that when thinking about OX.
605 When X >= Y, the alignment provided by Y adds no uncertainty factor
606 for branch ranges starting before X, so we can just round what we have.
607 But when X < Y, we don't know anything about the, so to speak,
608 `middle bits', so we have to assume the worst when aligning up from an
609 address mod X to one mod Y, which is Y - X. */
611 #ifndef LABEL_ALIGN
612 #define LABEL_ALIGN(LABEL) align_labels_log
613 #endif
615 #ifndef LABEL_ALIGN_MAX_SKIP
616 #define LABEL_ALIGN_MAX_SKIP align_labels_max_skip
617 #endif
619 #ifndef LOOP_ALIGN
620 #define LOOP_ALIGN(LABEL) align_loops_log
621 #endif
623 #ifndef LOOP_ALIGN_MAX_SKIP
624 #define LOOP_ALIGN_MAX_SKIP align_loops_max_skip
625 #endif
627 #ifndef LABEL_ALIGN_AFTER_BARRIER
628 #define LABEL_ALIGN_AFTER_BARRIER(LABEL) 0
629 #endif
631 #ifndef LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP
632 #define LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP 0
633 #endif
635 #ifndef JUMP_ALIGN
636 #define JUMP_ALIGN(LABEL) align_jumps_log
637 #endif
639 #ifndef JUMP_ALIGN_MAX_SKIP
640 #define JUMP_ALIGN_MAX_SKIP align_jumps_max_skip
641 #endif
643 #ifndef ADDR_VEC_ALIGN
644 static int
645 final_addr_vec_align (addr_vec)
646 rtx addr_vec;
648 int align = GET_MODE_SIZE (GET_MODE (PATTERN (addr_vec)));
650 if (align > BIGGEST_ALIGNMENT / BITS_PER_UNIT)
651 align = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
652 return exact_log2 (align);
656 #define ADDR_VEC_ALIGN(ADDR_VEC) final_addr_vec_align (ADDR_VEC)
657 #endif
659 #ifndef INSN_LENGTH_ALIGNMENT
660 #define INSN_LENGTH_ALIGNMENT(INSN) length_unit_log
661 #endif
663 #define INSN_SHUID(INSN) (uid_shuid[INSN_UID (INSN)])
665 static int min_labelno, max_labelno;
667 #define LABEL_TO_ALIGNMENT(LABEL) \
668 (label_align[CODE_LABEL_NUMBER (LABEL) - min_labelno].alignment)
670 #define LABEL_TO_MAX_SKIP(LABEL) \
671 (label_align[CODE_LABEL_NUMBER (LABEL) - min_labelno].max_skip)
673 /* For the benefit of port specific code do this also as a function. */
676 label_to_alignment (label)
677 rtx label;
679 return LABEL_TO_ALIGNMENT (label);
682 #ifdef HAVE_ATTR_length
683 /* The differences in addresses
684 between a branch and its target might grow or shrink depending on
685 the alignment the start insn of the range (the branch for a forward
686 branch or the label for a backward branch) starts out on; if these
687 differences are used naively, they can even oscillate infinitely.
688 We therefore want to compute a 'worst case' address difference that
689 is independent of the alignment the start insn of the range end
690 up on, and that is at least as large as the actual difference.
691 The function align_fuzz calculates the amount we have to add to the
692 naively computed difference, by traversing the part of the alignment
693 chain of the start insn of the range that is in front of the end insn
694 of the range, and considering for each alignment the maximum amount
695 that it might contribute to a size increase.
697 For casesi tables, we also want to know worst case minimum amounts of
698 address difference, in case a machine description wants to introduce
699 some common offset that is added to all offsets in a table.
700 For this purpose, align_fuzz with a growth argument of 0 computes the
701 appropriate adjustment. */
703 /* Compute the maximum delta by which the difference of the addresses of
704 START and END might grow / shrink due to a different address for start
705 which changes the size of alignment insns between START and END.
706 KNOWN_ALIGN_LOG is the alignment known for START.
707 GROWTH should be ~0 if the objective is to compute potential code size
708 increase, and 0 if the objective is to compute potential shrink.
709 The return value is undefined for any other value of GROWTH. */
711 static int
712 align_fuzz (start, end, known_align_log, growth)
713 rtx start, end;
714 int known_align_log;
715 unsigned growth;
717 int uid = INSN_UID (start);
718 rtx align_label;
719 int known_align = 1 << known_align_log;
720 int end_shuid = INSN_SHUID (end);
721 int fuzz = 0;
723 for (align_label = uid_align[uid]; align_label; align_label = uid_align[uid])
725 int align_addr, new_align;
727 uid = INSN_UID (align_label);
728 align_addr = INSN_ADDRESSES (uid) - insn_lengths[uid];
729 if (uid_shuid[uid] > end_shuid)
730 break;
731 known_align_log = LABEL_TO_ALIGNMENT (align_label);
732 new_align = 1 << known_align_log;
733 if (new_align < known_align)
734 continue;
735 fuzz += (-align_addr ^ growth) & (new_align - known_align);
736 known_align = new_align;
738 return fuzz;
741 /* Compute a worst-case reference address of a branch so that it
742 can be safely used in the presence of aligned labels. Since the
743 size of the branch itself is unknown, the size of the branch is
744 not included in the range. I.e. for a forward branch, the reference
745 address is the end address of the branch as known from the previous
746 branch shortening pass, minus a value to account for possible size
747 increase due to alignment. For a backward branch, it is the start
748 address of the branch as known from the current pass, plus a value
749 to account for possible size increase due to alignment.
750 NB.: Therefore, the maximum offset allowed for backward branches needs
751 to exclude the branch size. */
754 insn_current_reference_address (branch)
755 rtx branch;
757 rtx dest, seq;
758 int seq_uid;
760 if (! INSN_ADDRESSES_SET_P ())
761 return 0;
763 seq = NEXT_INSN (PREV_INSN (branch));
764 seq_uid = INSN_UID (seq);
765 if (GET_CODE (branch) != JUMP_INSN)
766 /* This can happen for example on the PA; the objective is to know the
767 offset to address something in front of the start of the function.
768 Thus, we can treat it like a backward branch.
769 We assume here that FUNCTION_BOUNDARY / BITS_PER_UNIT is larger than
770 any alignment we'd encounter, so we skip the call to align_fuzz. */
771 return insn_current_address;
772 dest = JUMP_LABEL (branch);
774 /* BRANCH has no proper alignment chain set, so use SEQ.
775 BRANCH also has no INSN_SHUID. */
776 if (INSN_SHUID (seq) < INSN_SHUID (dest))
778 /* Forward branch. */
779 return (insn_last_address + insn_lengths[seq_uid]
780 - align_fuzz (seq, dest, length_unit_log, ~0));
782 else
784 /* Backward branch. */
785 return (insn_current_address
786 + align_fuzz (dest, seq, length_unit_log, ~0));
789 #endif /* HAVE_ATTR_length */
791 void
792 compute_alignments ()
794 int i;
795 int log, max_skip, max_log;
797 if (label_align)
799 free (label_align);
800 label_align = 0;
803 max_labelno = max_label_num ();
804 min_labelno = get_first_label_num ();
805 label_align = (struct label_alignment *)
806 xcalloc (max_labelno - min_labelno + 1, sizeof (struct label_alignment));
808 /* If not optimizing or optimizing for size, don't assign any alignments. */
809 if (! optimize || optimize_size)
810 return;
812 for (i = 0; i < n_basic_blocks; i++)
814 basic_block bb = BASIC_BLOCK (i);
815 rtx label = bb->head;
816 int fallthru_frequency = 0, branch_frequency = 0, has_fallthru = 0;
817 edge e;
819 if (GET_CODE (label) != CODE_LABEL)
820 continue;
821 max_log = LABEL_ALIGN (label);
822 max_skip = LABEL_ALIGN_MAX_SKIP;
824 for (e = bb->pred; e; e = e->pred_next)
826 if (e->flags & EDGE_FALLTHRU)
827 has_fallthru = 1, fallthru_frequency += EDGE_FREQUENCY (e);
828 else
829 branch_frequency += EDGE_FREQUENCY (e);
832 /* There are two purposes to align block with no fallthru incoming edge:
833 1) to avoid fetch stalls when branch destination is near cache boundary
834 2) to improve cache efficiency in case the previous block is not executed
835 (so it does not need to be in the cache).
837 We to catch first case, we align frequently executed blocks.
838 To catch the second, we align blocks that are executed more frequently
839 than the predecessor and the predecessor is likely to not be executed
840 when function is called. */
842 if (!has_fallthru
843 && (branch_frequency > BB_FREQ_MAX / 10
844 || (bb->frequency > BASIC_BLOCK (i - 1)->frequency * 10
845 && (BASIC_BLOCK (i - 1)->frequency
846 <= ENTRY_BLOCK_PTR->frequency / 2))))
848 log = JUMP_ALIGN (label);
849 if (max_log < log)
851 max_log = log;
852 max_skip = JUMP_ALIGN_MAX_SKIP;
855 /* In case block is frequent and reached mostly by non-fallthru edge,
856 align it. It is most likely an first block of loop. */
857 if (has_fallthru
858 && branch_frequency + fallthru_frequency > BB_FREQ_MAX / 10
859 && branch_frequency > fallthru_frequency * 5)
861 log = LOOP_ALIGN (label);
862 if (max_log < log)
864 max_log = log;
865 max_skip = LOOP_ALIGN_MAX_SKIP;
868 LABEL_TO_ALIGNMENT (label) = max_log;
869 LABEL_TO_MAX_SKIP (label) = max_skip;
873 /* Make a pass over all insns and compute their actual lengths by shortening
874 any branches of variable length if possible. */
876 /* Give a default value for the lowest address in a function. */
878 #ifndef FIRST_INSN_ADDRESS
879 #define FIRST_INSN_ADDRESS 0
880 #endif
882 /* shorten_branches might be called multiple times: for example, the SH
883 port splits out-of-range conditional branches in MACHINE_DEPENDENT_REORG.
884 In order to do this, it needs proper length information, which it obtains
885 by calling shorten_branches. This cannot be collapsed with
886 shorten_branches itself into a single pass unless we also want to integrate
887 reorg.c, since the branch splitting exposes new instructions with delay
888 slots. */
890 void
891 shorten_branches (first)
892 rtx first ATTRIBUTE_UNUSED;
894 rtx insn;
895 int max_uid;
896 int i;
897 int max_log;
898 int max_skip;
899 #ifdef HAVE_ATTR_length
900 #define MAX_CODE_ALIGN 16
901 rtx seq;
902 int something_changed = 1;
903 char *varying_length;
904 rtx body;
905 int uid;
906 rtx align_tab[MAX_CODE_ALIGN];
908 #endif
910 /* Compute maximum UID and allocate label_align / uid_shuid. */
911 max_uid = get_max_uid ();
913 uid_shuid = (int *) xmalloc (max_uid * sizeof *uid_shuid);
915 if (max_labelno != max_label_num ())
917 int old = max_labelno;
918 int n_labels;
919 int n_old_labels;
921 max_labelno = max_label_num ();
923 n_labels = max_labelno - min_labelno + 1;
924 n_old_labels = old - min_labelno + 1;
926 label_align = (struct label_alignment *) xrealloc
927 (label_align, n_labels * sizeof (struct label_alignment));
929 /* Range of labels grows monotonically in the function. Abort here
930 means that the initialization of array got lost. */
931 if (n_old_labels > n_labels)
932 abort ();
934 memset (label_align + n_old_labels, 0,
935 (n_labels - n_old_labels) * sizeof (struct label_alignment));
938 /* Initialize label_align and set up uid_shuid to be strictly
939 monotonically rising with insn order. */
940 /* We use max_log here to keep track of the maximum alignment we want to
941 impose on the next CODE_LABEL (or the current one if we are processing
942 the CODE_LABEL itself). */
944 max_log = 0;
945 max_skip = 0;
947 for (insn = get_insns (), i = 1; insn; insn = NEXT_INSN (insn))
949 int log;
951 INSN_SHUID (insn) = i++;
952 if (INSN_P (insn))
954 /* reorg might make the first insn of a loop being run once only,
955 and delete the label in front of it. Then we want to apply
956 the loop alignment to the new label created by reorg, which
957 is separated by the former loop start insn from the
958 NOTE_INSN_LOOP_BEG. */
960 else if (GET_CODE (insn) == CODE_LABEL)
962 rtx next;
964 /* Merge in alignments computed by compute_alignments. */
965 log = LABEL_TO_ALIGNMENT (insn);
966 if (max_log < log)
968 max_log = log;
969 max_skip = LABEL_TO_MAX_SKIP (insn);
972 log = LABEL_ALIGN (insn);
973 if (max_log < log)
975 max_log = log;
976 max_skip = LABEL_ALIGN_MAX_SKIP;
978 next = NEXT_INSN (insn);
979 /* ADDR_VECs only take room if read-only data goes into the text
980 section. */
981 if (JUMP_TABLES_IN_TEXT_SECTION
982 #if !defined(READONLY_DATA_SECTION)
983 || 1
984 #endif
986 if (next && GET_CODE (next) == JUMP_INSN)
988 rtx nextbody = PATTERN (next);
989 if (GET_CODE (nextbody) == ADDR_VEC
990 || GET_CODE (nextbody) == ADDR_DIFF_VEC)
992 log = ADDR_VEC_ALIGN (next);
993 if (max_log < log)
995 max_log = log;
996 max_skip = LABEL_ALIGN_MAX_SKIP;
1000 LABEL_TO_ALIGNMENT (insn) = max_log;
1001 LABEL_TO_MAX_SKIP (insn) = max_skip;
1002 max_log = 0;
1003 max_skip = 0;
1005 else if (GET_CODE (insn) == BARRIER)
1007 rtx label;
1009 for (label = insn; label && ! INSN_P (label);
1010 label = NEXT_INSN (label))
1011 if (GET_CODE (label) == CODE_LABEL)
1013 log = LABEL_ALIGN_AFTER_BARRIER (insn);
1014 if (max_log < log)
1016 max_log = log;
1017 max_skip = LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP;
1019 break;
1023 #ifdef HAVE_ATTR_length
1025 /* Allocate the rest of the arrays. */
1026 insn_lengths = (int *) xmalloc (max_uid * sizeof (*insn_lengths));
1027 insn_lengths_max_uid = max_uid;
1028 /* Syntax errors can lead to labels being outside of the main insn stream.
1029 Initialize insn_addresses, so that we get reproducible results. */
1030 INSN_ADDRESSES_ALLOC (max_uid);
1032 varying_length = (char *) xcalloc (max_uid, sizeof (char));
1034 /* Initialize uid_align. We scan instructions
1035 from end to start, and keep in align_tab[n] the last seen insn
1036 that does an alignment of at least n+1, i.e. the successor
1037 in the alignment chain for an insn that does / has a known
1038 alignment of n. */
1039 uid_align = (rtx *) xcalloc (max_uid, sizeof *uid_align);
1041 for (i = MAX_CODE_ALIGN; --i >= 0;)
1042 align_tab[i] = NULL_RTX;
1043 seq = get_last_insn ();
1044 for (; seq; seq = PREV_INSN (seq))
1046 int uid = INSN_UID (seq);
1047 int log;
1048 log = (GET_CODE (seq) == CODE_LABEL ? LABEL_TO_ALIGNMENT (seq) : 0);
1049 uid_align[uid] = align_tab[0];
1050 if (log)
1052 /* Found an alignment label. */
1053 uid_align[uid] = align_tab[log];
1054 for (i = log - 1; i >= 0; i--)
1055 align_tab[i] = seq;
1058 #ifdef CASE_VECTOR_SHORTEN_MODE
1059 if (optimize)
1061 /* Look for ADDR_DIFF_VECs, and initialize their minimum and maximum
1062 label fields. */
1064 int min_shuid = INSN_SHUID (get_insns ()) - 1;
1065 int max_shuid = INSN_SHUID (get_last_insn ()) + 1;
1066 int rel;
1068 for (insn = first; insn != 0; insn = NEXT_INSN (insn))
1070 rtx min_lab = NULL_RTX, max_lab = NULL_RTX, pat;
1071 int len, i, min, max, insn_shuid;
1072 int min_align;
1073 addr_diff_vec_flags flags;
1075 if (GET_CODE (insn) != JUMP_INSN
1076 || GET_CODE (PATTERN (insn)) != ADDR_DIFF_VEC)
1077 continue;
1078 pat = PATTERN (insn);
1079 len = XVECLEN (pat, 1);
1080 if (len <= 0)
1081 abort ();
1082 min_align = MAX_CODE_ALIGN;
1083 for (min = max_shuid, max = min_shuid, i = len - 1; i >= 0; i--)
1085 rtx lab = XEXP (XVECEXP (pat, 1, i), 0);
1086 int shuid = INSN_SHUID (lab);
1087 if (shuid < min)
1089 min = shuid;
1090 min_lab = lab;
1092 if (shuid > max)
1094 max = shuid;
1095 max_lab = lab;
1097 if (min_align > LABEL_TO_ALIGNMENT (lab))
1098 min_align = LABEL_TO_ALIGNMENT (lab);
1100 XEXP (pat, 2) = gen_rtx_LABEL_REF (VOIDmode, min_lab);
1101 XEXP (pat, 3) = gen_rtx_LABEL_REF (VOIDmode, max_lab);
1102 insn_shuid = INSN_SHUID (insn);
1103 rel = INSN_SHUID (XEXP (XEXP (pat, 0), 0));
1104 flags.min_align = min_align;
1105 flags.base_after_vec = rel > insn_shuid;
1106 flags.min_after_vec = min > insn_shuid;
1107 flags.max_after_vec = max > insn_shuid;
1108 flags.min_after_base = min > rel;
1109 flags.max_after_base = max > rel;
1110 ADDR_DIFF_VEC_FLAGS (pat) = flags;
1113 #endif /* CASE_VECTOR_SHORTEN_MODE */
1115 /* Compute initial lengths, addresses, and varying flags for each insn. */
1116 for (insn_current_address = FIRST_INSN_ADDRESS, insn = first;
1117 insn != 0;
1118 insn_current_address += insn_lengths[uid], insn = NEXT_INSN (insn))
1120 uid = INSN_UID (insn);
1122 insn_lengths[uid] = 0;
1124 if (GET_CODE (insn) == CODE_LABEL)
1126 int log = LABEL_TO_ALIGNMENT (insn);
1127 if (log)
1129 int align = 1 << log;
1130 int new_address = (insn_current_address + align - 1) & -align;
1131 insn_lengths[uid] = new_address - insn_current_address;
1135 INSN_ADDRESSES (uid) = insn_current_address;
1137 if (GET_CODE (insn) == NOTE || GET_CODE (insn) == BARRIER
1138 || GET_CODE (insn) == CODE_LABEL)
1139 continue;
1140 if (INSN_DELETED_P (insn))
1141 continue;
1143 body = PATTERN (insn);
1144 if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
1146 /* This only takes room if read-only data goes into the text
1147 section. */
1148 if (JUMP_TABLES_IN_TEXT_SECTION
1149 #if !defined(READONLY_DATA_SECTION)
1150 || 1
1151 #endif
1153 insn_lengths[uid] = (XVECLEN (body,
1154 GET_CODE (body) == ADDR_DIFF_VEC)
1155 * GET_MODE_SIZE (GET_MODE (body)));
1156 /* Alignment is handled by ADDR_VEC_ALIGN. */
1158 else if (GET_CODE (body) == ASM_INPUT || asm_noperands (body) >= 0)
1159 insn_lengths[uid] = asm_insn_count (body) * insn_default_length (insn);
1160 else if (GET_CODE (body) == SEQUENCE)
1162 int i;
1163 int const_delay_slots;
1164 #ifdef DELAY_SLOTS
1165 const_delay_slots = const_num_delay_slots (XVECEXP (body, 0, 0));
1166 #else
1167 const_delay_slots = 0;
1168 #endif
1169 /* Inside a delay slot sequence, we do not do any branch shortening
1170 if the shortening could change the number of delay slots
1171 of the branch. */
1172 for (i = 0; i < XVECLEN (body, 0); i++)
1174 rtx inner_insn = XVECEXP (body, 0, i);
1175 int inner_uid = INSN_UID (inner_insn);
1176 int inner_length;
1178 if (GET_CODE (body) == ASM_INPUT
1179 || asm_noperands (PATTERN (XVECEXP (body, 0, i))) >= 0)
1180 inner_length = (asm_insn_count (PATTERN (inner_insn))
1181 * insn_default_length (inner_insn));
1182 else
1183 inner_length = insn_default_length (inner_insn);
1185 insn_lengths[inner_uid] = inner_length;
1186 if (const_delay_slots)
1188 if ((varying_length[inner_uid]
1189 = insn_variable_length_p (inner_insn)) != 0)
1190 varying_length[uid] = 1;
1191 INSN_ADDRESSES (inner_uid) = (insn_current_address
1192 + insn_lengths[uid]);
1194 else
1195 varying_length[inner_uid] = 0;
1196 insn_lengths[uid] += inner_length;
1199 else if (GET_CODE (body) != USE && GET_CODE (body) != CLOBBER)
1201 insn_lengths[uid] = insn_default_length (insn);
1202 varying_length[uid] = insn_variable_length_p (insn);
1205 /* If needed, do any adjustment. */
1206 #ifdef ADJUST_INSN_LENGTH
1207 ADJUST_INSN_LENGTH (insn, insn_lengths[uid]);
1208 if (insn_lengths[uid] < 0)
1209 fatal_insn ("negative insn length", insn);
1210 #endif
1213 /* Now loop over all the insns finding varying length insns. For each,
1214 get the current insn length. If it has changed, reflect the change.
1215 When nothing changes for a full pass, we are done. */
1217 while (something_changed)
1219 something_changed = 0;
1220 insn_current_align = MAX_CODE_ALIGN - 1;
1221 for (insn_current_address = FIRST_INSN_ADDRESS, insn = first;
1222 insn != 0;
1223 insn = NEXT_INSN (insn))
1225 int new_length;
1226 #ifdef ADJUST_INSN_LENGTH
1227 int tmp_length;
1228 #endif
1229 int length_align;
1231 uid = INSN_UID (insn);
1233 if (GET_CODE (insn) == CODE_LABEL)
1235 int log = LABEL_TO_ALIGNMENT (insn);
1236 if (log > insn_current_align)
1238 int align = 1 << log;
1239 int new_address= (insn_current_address + align - 1) & -align;
1240 insn_lengths[uid] = new_address - insn_current_address;
1241 insn_current_align = log;
1242 insn_current_address = new_address;
1244 else
1245 insn_lengths[uid] = 0;
1246 INSN_ADDRESSES (uid) = insn_current_address;
1247 continue;
1250 length_align = INSN_LENGTH_ALIGNMENT (insn);
1251 if (length_align < insn_current_align)
1252 insn_current_align = length_align;
1254 insn_last_address = INSN_ADDRESSES (uid);
1255 INSN_ADDRESSES (uid) = insn_current_address;
1257 #ifdef CASE_VECTOR_SHORTEN_MODE
1258 if (optimize && GET_CODE (insn) == JUMP_INSN
1259 && GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)
1261 rtx body = PATTERN (insn);
1262 int old_length = insn_lengths[uid];
1263 rtx rel_lab = XEXP (XEXP (body, 0), 0);
1264 rtx min_lab = XEXP (XEXP (body, 2), 0);
1265 rtx max_lab = XEXP (XEXP (body, 3), 0);
1266 int rel_addr = INSN_ADDRESSES (INSN_UID (rel_lab));
1267 int min_addr = INSN_ADDRESSES (INSN_UID (min_lab));
1268 int max_addr = INSN_ADDRESSES (INSN_UID (max_lab));
1269 rtx prev;
1270 int rel_align = 0;
1271 addr_diff_vec_flags flags;
1273 /* Avoid automatic aggregate initialization. */
1274 flags = ADDR_DIFF_VEC_FLAGS (body);
1276 /* Try to find a known alignment for rel_lab. */
1277 for (prev = rel_lab;
1278 prev
1279 && ! insn_lengths[INSN_UID (prev)]
1280 && ! (varying_length[INSN_UID (prev)] & 1);
1281 prev = PREV_INSN (prev))
1282 if (varying_length[INSN_UID (prev)] & 2)
1284 rel_align = LABEL_TO_ALIGNMENT (prev);
1285 break;
1288 /* See the comment on addr_diff_vec_flags in rtl.h for the
1289 meaning of the flags values. base: REL_LAB vec: INSN */
1290 /* Anything after INSN has still addresses from the last
1291 pass; adjust these so that they reflect our current
1292 estimate for this pass. */
1293 if (flags.base_after_vec)
1294 rel_addr += insn_current_address - insn_last_address;
1295 if (flags.min_after_vec)
1296 min_addr += insn_current_address - insn_last_address;
1297 if (flags.max_after_vec)
1298 max_addr += insn_current_address - insn_last_address;
1299 /* We want to know the worst case, i.e. lowest possible value
1300 for the offset of MIN_LAB. If MIN_LAB is after REL_LAB,
1301 its offset is positive, and we have to be wary of code shrink;
1302 otherwise, it is negative, and we have to be vary of code
1303 size increase. */
1304 if (flags.min_after_base)
1306 /* If INSN is between REL_LAB and MIN_LAB, the size
1307 changes we are about to make can change the alignment
1308 within the observed offset, therefore we have to break
1309 it up into two parts that are independent. */
1310 if (! flags.base_after_vec && flags.min_after_vec)
1312 min_addr -= align_fuzz (rel_lab, insn, rel_align, 0);
1313 min_addr -= align_fuzz (insn, min_lab, 0, 0);
1315 else
1316 min_addr -= align_fuzz (rel_lab, min_lab, rel_align, 0);
1318 else
1320 if (flags.base_after_vec && ! flags.min_after_vec)
1322 min_addr -= align_fuzz (min_lab, insn, 0, ~0);
1323 min_addr -= align_fuzz (insn, rel_lab, 0, ~0);
1325 else
1326 min_addr -= align_fuzz (min_lab, rel_lab, 0, ~0);
1328 /* Likewise, determine the highest lowest possible value
1329 for the offset of MAX_LAB. */
1330 if (flags.max_after_base)
1332 if (! flags.base_after_vec && flags.max_after_vec)
1334 max_addr += align_fuzz (rel_lab, insn, rel_align, ~0);
1335 max_addr += align_fuzz (insn, max_lab, 0, ~0);
1337 else
1338 max_addr += align_fuzz (rel_lab, max_lab, rel_align, ~0);
1340 else
1342 if (flags.base_after_vec && ! flags.max_after_vec)
1344 max_addr += align_fuzz (max_lab, insn, 0, 0);
1345 max_addr += align_fuzz (insn, rel_lab, 0, 0);
1347 else
1348 max_addr += align_fuzz (max_lab, rel_lab, 0, 0);
1350 PUT_MODE (body, CASE_VECTOR_SHORTEN_MODE (min_addr - rel_addr,
1351 max_addr - rel_addr,
1352 body));
1353 if (JUMP_TABLES_IN_TEXT_SECTION
1354 #if !defined(READONLY_DATA_SECTION)
1355 || 1
1356 #endif
1359 insn_lengths[uid]
1360 = (XVECLEN (body, 1) * GET_MODE_SIZE (GET_MODE (body)));
1361 insn_current_address += insn_lengths[uid];
1362 if (insn_lengths[uid] != old_length)
1363 something_changed = 1;
1366 continue;
1368 #endif /* CASE_VECTOR_SHORTEN_MODE */
1370 if (! (varying_length[uid]))
1372 if (GET_CODE (insn) == INSN
1373 && GET_CODE (PATTERN (insn)) == SEQUENCE)
1375 int i;
1377 body = PATTERN (insn);
1378 for (i = 0; i < XVECLEN (body, 0); i++)
1380 rtx inner_insn = XVECEXP (body, 0, i);
1381 int inner_uid = INSN_UID (inner_insn);
1383 INSN_ADDRESSES (inner_uid) = insn_current_address;
1385 insn_current_address += insn_lengths[inner_uid];
1388 else
1389 insn_current_address += insn_lengths[uid];
1391 continue;
1394 if (GET_CODE (insn) == INSN && GET_CODE (PATTERN (insn)) == SEQUENCE)
1396 int i;
1398 body = PATTERN (insn);
1399 new_length = 0;
1400 for (i = 0; i < XVECLEN (body, 0); i++)
1402 rtx inner_insn = XVECEXP (body, 0, i);
1403 int inner_uid = INSN_UID (inner_insn);
1404 int inner_length;
1406 INSN_ADDRESSES (inner_uid) = insn_current_address;
1408 /* insn_current_length returns 0 for insns with a
1409 non-varying length. */
1410 if (! varying_length[inner_uid])
1411 inner_length = insn_lengths[inner_uid];
1412 else
1413 inner_length = insn_current_length (inner_insn);
1415 if (inner_length != insn_lengths[inner_uid])
1417 insn_lengths[inner_uid] = inner_length;
1418 something_changed = 1;
1420 insn_current_address += insn_lengths[inner_uid];
1421 new_length += inner_length;
1424 else
1426 new_length = insn_current_length (insn);
1427 insn_current_address += new_length;
1430 #ifdef ADJUST_INSN_LENGTH
1431 /* If needed, do any adjustment. */
1432 tmp_length = new_length;
1433 ADJUST_INSN_LENGTH (insn, new_length);
1434 insn_current_address += (new_length - tmp_length);
1435 #endif
1437 if (new_length != insn_lengths[uid])
1439 insn_lengths[uid] = new_length;
1440 something_changed = 1;
1443 /* For a non-optimizing compile, do only a single pass. */
1444 if (!optimize)
1445 break;
1448 free (varying_length);
1450 #endif /* HAVE_ATTR_length */
1453 #ifdef HAVE_ATTR_length
1454 /* Given the body of an INSN known to be generated by an ASM statement, return
1455 the number of machine instructions likely to be generated for this insn.
1456 This is used to compute its length. */
1458 static int
1459 asm_insn_count (body)
1460 rtx body;
1462 const char *template;
1463 int count = 1;
1465 if (GET_CODE (body) == ASM_INPUT)
1466 template = XSTR (body, 0);
1467 else
1468 template = decode_asm_operands (body, NULL, NULL, NULL, NULL);
1470 for (; *template; template++)
1471 if (IS_ASM_LOGICAL_LINE_SEPARATOR (*template) || *template == '\n')
1472 count++;
1474 return count;
1476 #endif
1478 /* Output assembler code for the start of a function,
1479 and initialize some of the variables in this file
1480 for the new function. The label for the function and associated
1481 assembler pseudo-ops have already been output in `assemble_start_function'.
1483 FIRST is the first insn of the rtl for the function being compiled.
1484 FILE is the file to write assembler code to.
1485 OPTIMIZE is nonzero if we should eliminate redundant
1486 test and compare insns. */
1488 void
1489 final_start_function (first, file, optimize)
1490 rtx first;
1491 FILE *file;
1492 int optimize ATTRIBUTE_UNUSED;
1494 block_depth = 0;
1496 this_is_asm_operands = 0;
1498 #ifdef NON_SAVING_SETJMP
1499 /* A function that calls setjmp should save and restore all the
1500 call-saved registers on a system where longjmp clobbers them. */
1501 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
1503 int i;
1505 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
1506 if (!call_used_regs[i])
1507 regs_ever_live[i] = 1;
1509 #endif
1511 if (NOTE_LINE_NUMBER (first) != NOTE_INSN_DELETED)
1512 notice_source_line (first);
1513 high_block_linenum = high_function_linenum = last_linenum;
1515 (*debug_hooks->begin_prologue) (last_linenum, last_filename);
1517 #if defined (DWARF2_UNWIND_INFO) || defined (IA64_UNWIND_INFO)
1518 if (write_symbols != DWARF2_DEBUG && write_symbols != VMS_AND_DWARF2_DEBUG)
1519 dwarf2out_begin_prologue (0, NULL);
1520 #endif
1522 #ifdef LEAF_REG_REMAP
1523 if (current_function_uses_only_leaf_regs)
1524 leaf_renumber_regs (first);
1525 #endif
1527 /* The Sun386i and perhaps other machines don't work right
1528 if the profiling code comes after the prologue. */
1529 #ifdef PROFILE_BEFORE_PROLOGUE
1530 if (current_function_profile)
1531 profile_function (file);
1532 #endif /* PROFILE_BEFORE_PROLOGUE */
1534 #if defined (DWARF2_UNWIND_INFO) && defined (HAVE_prologue)
1535 if (dwarf2out_do_frame ())
1536 dwarf2out_frame_debug (NULL_RTX);
1537 #endif
1539 /* If debugging, assign block numbers to all of the blocks in this
1540 function. */
1541 if (write_symbols)
1543 remove_unnecessary_notes ();
1544 reorder_blocks ();
1545 number_blocks (current_function_decl);
1546 /* We never actually put out begin/end notes for the top-level
1547 block in the function. But, conceptually, that block is
1548 always needed. */
1549 TREE_ASM_WRITTEN (DECL_INITIAL (current_function_decl)) = 1;
1552 /* First output the function prologue: code to set up the stack frame. */
1553 (*targetm.asm_out.function_prologue) (file, get_frame_size ());
1555 #ifdef VMS_DEBUGGING_INFO
1556 /* Output label after the prologue of the function. */
1557 if (write_symbols == VMS_DEBUG || write_symbols == VMS_AND_DWARF2_DEBUG)
1558 vmsdbgout_after_prologue ();
1559 #endif
1561 /* If the machine represents the prologue as RTL, the profiling code must
1562 be emitted when NOTE_INSN_PROLOGUE_END is scanned. */
1563 #ifdef HAVE_prologue
1564 if (! HAVE_prologue)
1565 #endif
1566 profile_after_prologue (file);
1568 profile_label_no++;
1571 static void
1572 profile_after_prologue (file)
1573 FILE *file ATTRIBUTE_UNUSED;
1575 #ifndef PROFILE_BEFORE_PROLOGUE
1576 if (current_function_profile)
1577 profile_function (file);
1578 #endif /* not PROFILE_BEFORE_PROLOGUE */
1581 static void
1582 profile_function (file)
1583 FILE *file ATTRIBUTE_UNUSED;
1585 #ifndef NO_PROFILE_COUNTERS
1586 int align = MIN (BIGGEST_ALIGNMENT, LONG_TYPE_SIZE);
1587 #endif
1588 #if defined(ASM_OUTPUT_REG_PUSH)
1589 #if defined(STRUCT_VALUE_INCOMING_REGNUM) || defined(STRUCT_VALUE_REGNUM)
1590 int sval = current_function_returns_struct;
1591 #endif
1592 #if defined(STATIC_CHAIN_INCOMING_REGNUM) || defined(STATIC_CHAIN_REGNUM)
1593 int cxt = current_function_needs_context;
1594 #endif
1595 #endif /* ASM_OUTPUT_REG_PUSH */
1597 #ifndef NO_PROFILE_COUNTERS
1598 data_section ();
1599 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
1600 ASM_OUTPUT_INTERNAL_LABEL (file, "LP", profile_label_no);
1601 assemble_integer (const0_rtx, LONG_TYPE_SIZE / BITS_PER_UNIT, align, 1);
1602 #endif
1604 function_section (current_function_decl);
1606 #if defined(STRUCT_VALUE_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1607 if (sval)
1608 ASM_OUTPUT_REG_PUSH (file, STRUCT_VALUE_INCOMING_REGNUM);
1609 #else
1610 #if defined(STRUCT_VALUE_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1611 if (sval)
1613 ASM_OUTPUT_REG_PUSH (file, STRUCT_VALUE_REGNUM);
1615 #endif
1616 #endif
1618 #if defined(STATIC_CHAIN_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1619 if (cxt)
1620 ASM_OUTPUT_REG_PUSH (file, STATIC_CHAIN_INCOMING_REGNUM);
1621 #else
1622 #if defined(STATIC_CHAIN_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1623 if (cxt)
1625 ASM_OUTPUT_REG_PUSH (file, STATIC_CHAIN_REGNUM);
1627 #endif
1628 #endif
1630 FUNCTION_PROFILER (file, profile_label_no);
1632 #if defined(STATIC_CHAIN_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1633 if (cxt)
1634 ASM_OUTPUT_REG_POP (file, STATIC_CHAIN_INCOMING_REGNUM);
1635 #else
1636 #if defined(STATIC_CHAIN_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1637 if (cxt)
1639 ASM_OUTPUT_REG_POP (file, STATIC_CHAIN_REGNUM);
1641 #endif
1642 #endif
1644 #if defined(STRUCT_VALUE_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1645 if (sval)
1646 ASM_OUTPUT_REG_POP (file, STRUCT_VALUE_INCOMING_REGNUM);
1647 #else
1648 #if defined(STRUCT_VALUE_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1649 if (sval)
1651 ASM_OUTPUT_REG_POP (file, STRUCT_VALUE_REGNUM);
1653 #endif
1654 #endif
1657 /* Output assembler code for the end of a function.
1658 For clarity, args are same as those of `final_start_function'
1659 even though not all of them are needed. */
1661 void
1662 final_end_function ()
1664 app_disable ();
1666 (*debug_hooks->end_function) (high_function_linenum);
1668 /* Finally, output the function epilogue:
1669 code to restore the stack frame and return to the caller. */
1670 (*targetm.asm_out.function_epilogue) (asm_out_file, get_frame_size ());
1672 /* And debug output. */
1673 (*debug_hooks->end_epilogue) ();
1675 #if defined (DWARF2_UNWIND_INFO)
1676 if (write_symbols != DWARF2_DEBUG && write_symbols != VMS_AND_DWARF2_DEBUG
1677 && dwarf2out_do_frame ())
1678 dwarf2out_end_epilogue ();
1679 #endif
1682 /* Output assembler code for some insns: all or part of a function.
1683 For description of args, see `final_start_function', above.
1685 PRESCAN is 1 if we are not really outputting,
1686 just scanning as if we were outputting.
1687 Prescanning deletes and rearranges insns just like ordinary output.
1688 PRESCAN is -2 if we are outputting after having prescanned.
1689 In this case, don't try to delete or rearrange insns
1690 because that has already been done.
1691 Prescanning is done only on certain machines. */
1693 void
1694 final (first, file, optimize, prescan)
1695 rtx first;
1696 FILE *file;
1697 int optimize;
1698 int prescan;
1700 rtx insn;
1701 int max_line = 0;
1702 int max_uid = 0;
1704 last_ignored_compare = 0;
1705 new_block = 1;
1707 /* Make a map indicating which line numbers appear in this function.
1708 When producing SDB debugging info, delete troublesome line number
1709 notes from inlined functions in other files as well as duplicate
1710 line number notes. */
1711 #ifdef SDB_DEBUGGING_INFO
1712 if (write_symbols == SDB_DEBUG)
1714 rtx last = 0;
1715 for (insn = first; insn; insn = NEXT_INSN (insn))
1716 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
1718 if ((RTX_INTEGRATED_P (insn)
1719 && strcmp (NOTE_SOURCE_FILE (insn), main_input_filename) != 0)
1720 || (last != 0
1721 && NOTE_LINE_NUMBER (insn) == NOTE_LINE_NUMBER (last)
1722 && NOTE_SOURCE_FILE (insn) == NOTE_SOURCE_FILE (last)))
1724 delete_insn (insn); /* Use delete_note. */
1725 continue;
1727 last = insn;
1728 if (NOTE_LINE_NUMBER (insn) > max_line)
1729 max_line = NOTE_LINE_NUMBER (insn);
1732 else
1733 #endif
1735 for (insn = first; insn; insn = NEXT_INSN (insn))
1736 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > max_line)
1737 max_line = NOTE_LINE_NUMBER (insn);
1740 line_note_exists = (char *) xcalloc (max_line + 1, sizeof (char));
1742 for (insn = first; insn; insn = NEXT_INSN (insn))
1744 if (INSN_UID (insn) > max_uid) /* find largest UID */
1745 max_uid = INSN_UID (insn);
1746 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
1747 line_note_exists[NOTE_LINE_NUMBER (insn)] = 1;
1748 #ifdef HAVE_cc0
1749 /* If CC tracking across branches is enabled, record the insn which
1750 jumps to each branch only reached from one place. */
1751 if (optimize && GET_CODE (insn) == JUMP_INSN)
1753 rtx lab = JUMP_LABEL (insn);
1754 if (lab && LABEL_NUSES (lab) == 1)
1756 LABEL_REFS (lab) = insn;
1759 #endif
1762 init_recog ();
1764 CC_STATUS_INIT;
1766 /* Output the insns. */
1767 for (insn = NEXT_INSN (first); insn;)
1769 #ifdef HAVE_ATTR_length
1770 if ((unsigned) INSN_UID (insn) >= INSN_ADDRESSES_SIZE ())
1772 #ifdef STACK_REGS
1773 /* Irritatingly, the reg-stack pass is creating new instructions
1774 and because of REG_DEAD note abuse it has to run after
1775 shorten_branches. Fake address of -1 then. */
1776 insn_current_address = -1;
1777 #else
1778 /* This can be triggered by bugs elsewhere in the compiler if
1779 new insns are created after init_insn_lengths is called. */
1780 abort ();
1781 #endif
1783 else
1784 insn_current_address = INSN_ADDRESSES (INSN_UID (insn));
1785 #endif /* HAVE_ATTR_length */
1787 insn = final_scan_insn (insn, file, optimize, prescan, 0);
1790 free (line_note_exists);
1791 line_note_exists = NULL;
1794 const char *
1795 get_insn_template (code, insn)
1796 int code;
1797 rtx insn;
1799 const void *output = insn_data[code].output;
1800 switch (insn_data[code].output_format)
1802 case INSN_OUTPUT_FORMAT_SINGLE:
1803 return (const char *) output;
1804 case INSN_OUTPUT_FORMAT_MULTI:
1805 return ((const char *const *) output)[which_alternative];
1806 case INSN_OUTPUT_FORMAT_FUNCTION:
1807 if (insn == NULL)
1808 abort ();
1809 return (*(insn_output_fn) output) (recog_data.operand, insn);
1811 default:
1812 abort ();
1816 /* The final scan for one insn, INSN.
1817 Args are same as in `final', except that INSN
1818 is the insn being scanned.
1819 Value returned is the next insn to be scanned.
1821 NOPEEPHOLES is the flag to disallow peephole processing (currently
1822 used for within delayed branch sequence output). */
1825 final_scan_insn (insn, file, optimize, prescan, nopeepholes)
1826 rtx insn;
1827 FILE *file;
1828 int optimize ATTRIBUTE_UNUSED;
1829 int prescan;
1830 int nopeepholes ATTRIBUTE_UNUSED;
1832 #ifdef HAVE_cc0
1833 rtx set;
1834 #endif
1836 insn_counter++;
1838 /* Ignore deleted insns. These can occur when we split insns (due to a
1839 template of "#") while not optimizing. */
1840 if (INSN_DELETED_P (insn))
1841 return NEXT_INSN (insn);
1843 switch (GET_CODE (insn))
1845 case NOTE:
1846 if (prescan > 0)
1847 break;
1849 switch (NOTE_LINE_NUMBER (insn))
1851 case NOTE_INSN_DELETED:
1852 case NOTE_INSN_LOOP_BEG:
1853 case NOTE_INSN_LOOP_END:
1854 case NOTE_INSN_LOOP_END_TOP_COND:
1855 case NOTE_INSN_LOOP_CONT:
1856 case NOTE_INSN_LOOP_VTOP:
1857 case NOTE_INSN_FUNCTION_END:
1858 case NOTE_INSN_REPEATED_LINE_NUMBER:
1859 case NOTE_INSN_RANGE_BEG:
1860 case NOTE_INSN_RANGE_END:
1861 case NOTE_INSN_LIVE:
1862 case NOTE_INSN_EXPECTED_VALUE:
1863 break;
1865 case NOTE_INSN_BASIC_BLOCK:
1866 #ifdef IA64_UNWIND_INFO
1867 IA64_UNWIND_EMIT (asm_out_file, insn);
1868 #endif
1869 if (flag_debug_asm)
1870 fprintf (asm_out_file, "\t%s basic block %d\n",
1871 ASM_COMMENT_START, NOTE_BASIC_BLOCK (insn)->index);
1872 break;
1874 case NOTE_INSN_EH_REGION_BEG:
1875 ASM_OUTPUT_DEBUG_LABEL (asm_out_file, "LEHB",
1876 NOTE_EH_HANDLER (insn));
1877 break;
1879 case NOTE_INSN_EH_REGION_END:
1880 ASM_OUTPUT_DEBUG_LABEL (asm_out_file, "LEHE",
1881 NOTE_EH_HANDLER (insn));
1882 break;
1884 case NOTE_INSN_PROLOGUE_END:
1885 (*targetm.asm_out.function_end_prologue) (file);
1886 profile_after_prologue (file);
1887 break;
1889 case NOTE_INSN_EPILOGUE_BEG:
1890 (*targetm.asm_out.function_begin_epilogue) (file);
1891 break;
1893 case NOTE_INSN_FUNCTION_BEG:
1894 app_disable ();
1895 (*debug_hooks->end_prologue) (last_linenum);
1896 break;
1898 case NOTE_INSN_BLOCK_BEG:
1899 if (debug_info_level == DINFO_LEVEL_NORMAL
1900 || debug_info_level == DINFO_LEVEL_VERBOSE
1901 || write_symbols == DWARF_DEBUG
1902 || write_symbols == DWARF2_DEBUG
1903 || write_symbols == VMS_AND_DWARF2_DEBUG
1904 || write_symbols == VMS_DEBUG)
1906 int n = BLOCK_NUMBER (NOTE_BLOCK (insn));
1908 app_disable ();
1909 ++block_depth;
1910 high_block_linenum = last_linenum;
1912 /* Output debugging info about the symbol-block beginning. */
1913 (*debug_hooks->begin_block) (last_linenum, n);
1915 /* Mark this block as output. */
1916 TREE_ASM_WRITTEN (NOTE_BLOCK (insn)) = 1;
1918 break;
1920 case NOTE_INSN_BLOCK_END:
1921 if (debug_info_level == DINFO_LEVEL_NORMAL
1922 || debug_info_level == DINFO_LEVEL_VERBOSE
1923 || write_symbols == DWARF_DEBUG
1924 || write_symbols == DWARF2_DEBUG
1925 || write_symbols == VMS_AND_DWARF2_DEBUG
1926 || write_symbols == VMS_DEBUG)
1928 int n = BLOCK_NUMBER (NOTE_BLOCK (insn));
1930 app_disable ();
1932 /* End of a symbol-block. */
1933 --block_depth;
1934 if (block_depth < 0)
1935 abort ();
1937 (*debug_hooks->end_block) (high_block_linenum, n);
1939 break;
1941 case NOTE_INSN_DELETED_LABEL:
1942 /* Emit the label. We may have deleted the CODE_LABEL because
1943 the label could be proved to be unreachable, though still
1944 referenced (in the form of having its address taken. */
1945 ASM_OUTPUT_DEBUG_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
1946 break;
1948 case 0:
1949 break;
1951 default:
1952 if (NOTE_LINE_NUMBER (insn) <= 0)
1953 abort ();
1955 /* This note is a line-number. */
1957 rtx note;
1958 int note_after = 0;
1960 /* If there is anything real after this note, output it.
1961 If another line note follows, omit this one. */
1962 for (note = NEXT_INSN (insn); note; note = NEXT_INSN (note))
1964 if (GET_CODE (note) != NOTE && GET_CODE (note) != CODE_LABEL)
1965 break;
1967 /* These types of notes can be significant
1968 so make sure the preceding line number stays. */
1969 else if (GET_CODE (note) == NOTE
1970 && (NOTE_LINE_NUMBER (note) == NOTE_INSN_BLOCK_BEG
1971 || NOTE_LINE_NUMBER (note) == NOTE_INSN_BLOCK_END
1972 || NOTE_LINE_NUMBER (note) == NOTE_INSN_FUNCTION_BEG))
1973 break;
1974 else if (GET_CODE (note) == NOTE && NOTE_LINE_NUMBER (note) > 0)
1976 /* Another line note follows; we can delete this note
1977 if no intervening line numbers have notes elsewhere. */
1978 int num;
1979 for (num = NOTE_LINE_NUMBER (insn) + 1;
1980 num < NOTE_LINE_NUMBER (note);
1981 num++)
1982 if (line_note_exists[num])
1983 break;
1985 if (num >= NOTE_LINE_NUMBER (note))
1986 note_after = 1;
1987 break;
1991 /* Output this line note if it is the first or the last line
1992 note in a row. */
1993 if (!note_after)
1995 notice_source_line (insn);
1996 (*debug_hooks->source_line) (last_linenum, last_filename);
1999 break;
2001 break;
2003 case BARRIER:
2004 #if defined (DWARF2_UNWIND_INFO)
2005 if (dwarf2out_do_frame ())
2006 dwarf2out_frame_debug (insn);
2007 #endif
2008 break;
2010 case CODE_LABEL:
2011 /* The target port might emit labels in the output function for
2012 some insn, e.g. sh.c output_branchy_insn. */
2013 if (CODE_LABEL_NUMBER (insn) <= max_labelno)
2015 int align = LABEL_TO_ALIGNMENT (insn);
2016 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
2017 int max_skip = LABEL_TO_MAX_SKIP (insn);
2018 #endif
2020 if (align && NEXT_INSN (insn))
2022 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
2023 ASM_OUTPUT_MAX_SKIP_ALIGN (file, align, max_skip);
2024 #else
2025 ASM_OUTPUT_ALIGN (file, align);
2026 #endif
2029 #ifdef HAVE_cc0
2030 CC_STATUS_INIT;
2031 /* If this label is reached from only one place, set the condition
2032 codes from the instruction just before the branch. */
2034 /* Disabled because some insns set cc_status in the C output code
2035 and NOTICE_UPDATE_CC alone can set incorrect status. */
2036 if (0 /* optimize && LABEL_NUSES (insn) == 1*/)
2038 rtx jump = LABEL_REFS (insn);
2039 rtx barrier = prev_nonnote_insn (insn);
2040 rtx prev;
2041 /* If the LABEL_REFS field of this label has been set to point
2042 at a branch, the predecessor of the branch is a regular
2043 insn, and that branch is the only way to reach this label,
2044 set the condition codes based on the branch and its
2045 predecessor. */
2046 if (barrier && GET_CODE (barrier) == BARRIER
2047 && jump && GET_CODE (jump) == JUMP_INSN
2048 && (prev = prev_nonnote_insn (jump))
2049 && GET_CODE (prev) == INSN)
2051 NOTICE_UPDATE_CC (PATTERN (prev), prev);
2052 NOTICE_UPDATE_CC (PATTERN (jump), jump);
2055 #endif
2056 if (prescan > 0)
2057 break;
2058 new_block = 1;
2060 #ifdef FINAL_PRESCAN_LABEL
2061 FINAL_PRESCAN_INSN (insn, NULL, 0);
2062 #endif
2064 if (LABEL_NAME (insn))
2065 (*debug_hooks->label) (insn);
2067 if (app_on)
2069 fputs (ASM_APP_OFF, file);
2070 app_on = 0;
2072 if (NEXT_INSN (insn) != 0
2073 && GET_CODE (NEXT_INSN (insn)) == JUMP_INSN)
2075 rtx nextbody = PATTERN (NEXT_INSN (insn));
2077 /* If this label is followed by a jump-table,
2078 make sure we put the label in the read-only section. Also
2079 possibly write the label and jump table together. */
2081 if (GET_CODE (nextbody) == ADDR_VEC
2082 || GET_CODE (nextbody) == ADDR_DIFF_VEC)
2084 #if defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC)
2085 /* In this case, the case vector is being moved by the
2086 target, so don't output the label at all. Leave that
2087 to the back end macros. */
2088 #else
2089 if (! JUMP_TABLES_IN_TEXT_SECTION)
2091 int log_align;
2093 readonly_data_section ();
2095 #ifdef ADDR_VEC_ALIGN
2096 log_align = ADDR_VEC_ALIGN (NEXT_INSN (insn));
2097 #else
2098 log_align = exact_log2 (BIGGEST_ALIGNMENT / BITS_PER_UNIT);
2099 #endif
2100 ASM_OUTPUT_ALIGN (file, log_align);
2102 else
2103 function_section (current_function_decl);
2105 #ifdef ASM_OUTPUT_CASE_LABEL
2106 ASM_OUTPUT_CASE_LABEL (file, "L", CODE_LABEL_NUMBER (insn),
2107 NEXT_INSN (insn));
2108 #else
2109 if (LABEL_ALTERNATE_NAME (insn))
2110 ASM_OUTPUT_ALTERNATE_LABEL_NAME (file, insn);
2111 else
2112 ASM_OUTPUT_INTERNAL_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
2113 #endif
2114 #endif
2115 break;
2118 if (LABEL_ALTERNATE_NAME (insn))
2119 ASM_OUTPUT_ALTERNATE_LABEL_NAME (file, insn);
2120 else
2121 ASM_OUTPUT_INTERNAL_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
2122 break;
2124 default:
2126 rtx body = PATTERN (insn);
2127 int insn_code_number;
2128 const char *template;
2129 rtx note;
2131 /* An INSN, JUMP_INSN or CALL_INSN.
2132 First check for special kinds that recog doesn't recognize. */
2134 if (GET_CODE (body) == USE /* These are just declarations */
2135 || GET_CODE (body) == CLOBBER)
2136 break;
2138 #ifdef HAVE_cc0
2139 /* If there is a REG_CC_SETTER note on this insn, it means that
2140 the setting of the condition code was done in the delay slot
2141 of the insn that branched here. So recover the cc status
2142 from the insn that set it. */
2144 note = find_reg_note (insn, REG_CC_SETTER, NULL_RTX);
2145 if (note)
2147 NOTICE_UPDATE_CC (PATTERN (XEXP (note, 0)), XEXP (note, 0));
2148 cc_prev_status = cc_status;
2150 #endif
2152 /* Detect insns that are really jump-tables
2153 and output them as such. */
2155 if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
2157 #if !(defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC))
2158 int vlen, idx;
2159 #endif
2161 if (prescan > 0)
2162 break;
2164 if (app_on)
2166 fputs (ASM_APP_OFF, file);
2167 app_on = 0;
2170 #if defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC)
2171 if (GET_CODE (body) == ADDR_VEC)
2173 #ifdef ASM_OUTPUT_ADDR_VEC
2174 ASM_OUTPUT_ADDR_VEC (PREV_INSN (insn), body);
2175 #else
2176 abort ();
2177 #endif
2179 else
2181 #ifdef ASM_OUTPUT_ADDR_DIFF_VEC
2182 ASM_OUTPUT_ADDR_DIFF_VEC (PREV_INSN (insn), body);
2183 #else
2184 abort ();
2185 #endif
2187 #else
2188 vlen = XVECLEN (body, GET_CODE (body) == ADDR_DIFF_VEC);
2189 for (idx = 0; idx < vlen; idx++)
2191 if (GET_CODE (body) == ADDR_VEC)
2193 #ifdef ASM_OUTPUT_ADDR_VEC_ELT
2194 ASM_OUTPUT_ADDR_VEC_ELT
2195 (file, CODE_LABEL_NUMBER (XEXP (XVECEXP (body, 0, idx), 0)));
2196 #else
2197 abort ();
2198 #endif
2200 else
2202 #ifdef ASM_OUTPUT_ADDR_DIFF_ELT
2203 ASM_OUTPUT_ADDR_DIFF_ELT
2204 (file,
2205 body,
2206 CODE_LABEL_NUMBER (XEXP (XVECEXP (body, 1, idx), 0)),
2207 CODE_LABEL_NUMBER (XEXP (XEXP (body, 0), 0)));
2208 #else
2209 abort ();
2210 #endif
2213 #ifdef ASM_OUTPUT_CASE_END
2214 ASM_OUTPUT_CASE_END (file,
2215 CODE_LABEL_NUMBER (PREV_INSN (insn)),
2216 insn);
2217 #endif
2218 #endif
2220 function_section (current_function_decl);
2222 break;
2225 if (GET_CODE (body) == ASM_INPUT)
2227 const char *string = XSTR (body, 0);
2229 /* There's no telling what that did to the condition codes. */
2230 CC_STATUS_INIT;
2231 if (prescan > 0)
2232 break;
2234 if (string[0])
2236 if (! app_on)
2238 fputs (ASM_APP_ON, file);
2239 app_on = 1;
2241 fprintf (asm_out_file, "\t%s\n", string);
2243 break;
2246 /* Detect `asm' construct with operands. */
2247 if (asm_noperands (body) >= 0)
2249 unsigned int noperands = asm_noperands (body);
2250 rtx *ops = (rtx *) alloca (noperands * sizeof (rtx));
2251 const char *string;
2253 /* There's no telling what that did to the condition codes. */
2254 CC_STATUS_INIT;
2255 if (prescan > 0)
2256 break;
2258 /* Get out the operand values. */
2259 string = decode_asm_operands (body, ops, NULL, NULL, NULL);
2260 /* Inhibit aborts on what would otherwise be compiler bugs. */
2261 insn_noperands = noperands;
2262 this_is_asm_operands = insn;
2264 /* Output the insn using them. */
2265 if (string[0])
2267 if (! app_on)
2269 fputs (ASM_APP_ON, file);
2270 app_on = 1;
2272 output_asm_insn (string, ops);
2275 this_is_asm_operands = 0;
2276 break;
2279 if (prescan <= 0 && app_on)
2281 fputs (ASM_APP_OFF, file);
2282 app_on = 0;
2285 if (GET_CODE (body) == SEQUENCE)
2287 /* A delayed-branch sequence */
2288 int i;
2289 rtx next;
2291 if (prescan > 0)
2292 break;
2293 final_sequence = body;
2295 /* The first insn in this SEQUENCE might be a JUMP_INSN that will
2296 force the restoration of a comparison that was previously
2297 thought unnecessary. If that happens, cancel this sequence
2298 and cause that insn to be restored. */
2300 next = final_scan_insn (XVECEXP (body, 0, 0), file, 0, prescan, 1);
2301 if (next != XVECEXP (body, 0, 1))
2303 final_sequence = 0;
2304 return next;
2307 for (i = 1; i < XVECLEN (body, 0); i++)
2309 rtx insn = XVECEXP (body, 0, i);
2310 rtx next = NEXT_INSN (insn);
2311 /* We loop in case any instruction in a delay slot gets
2312 split. */
2314 insn = final_scan_insn (insn, file, 0, prescan, 1);
2315 while (insn != next);
2317 #ifdef DBR_OUTPUT_SEQEND
2318 DBR_OUTPUT_SEQEND (file);
2319 #endif
2320 final_sequence = 0;
2322 /* If the insn requiring the delay slot was a CALL_INSN, the
2323 insns in the delay slot are actually executed before the
2324 called function. Hence we don't preserve any CC-setting
2325 actions in these insns and the CC must be marked as being
2326 clobbered by the function. */
2327 if (GET_CODE (XVECEXP (body, 0, 0)) == CALL_INSN)
2329 CC_STATUS_INIT;
2331 break;
2334 /* We have a real machine instruction as rtl. */
2336 body = PATTERN (insn);
2338 #ifdef HAVE_cc0
2339 set = single_set (insn);
2341 /* Check for redundant test and compare instructions
2342 (when the condition codes are already set up as desired).
2343 This is done only when optimizing; if not optimizing,
2344 it should be possible for the user to alter a variable
2345 with the debugger in between statements
2346 and the next statement should reexamine the variable
2347 to compute the condition codes. */
2349 if (optimize)
2351 #if 0
2352 rtx set = single_set (insn);
2353 #endif
2355 if (set
2356 && GET_CODE (SET_DEST (set)) == CC0
2357 && insn != last_ignored_compare)
2359 if (GET_CODE (SET_SRC (set)) == SUBREG)
2360 SET_SRC (set) = alter_subreg (&SET_SRC (set));
2361 else if (GET_CODE (SET_SRC (set)) == COMPARE)
2363 if (GET_CODE (XEXP (SET_SRC (set), 0)) == SUBREG)
2364 XEXP (SET_SRC (set), 0)
2365 = alter_subreg (&XEXP (SET_SRC (set), 0));
2366 if (GET_CODE (XEXP (SET_SRC (set), 1)) == SUBREG)
2367 XEXP (SET_SRC (set), 1)
2368 = alter_subreg (&XEXP (SET_SRC (set), 1));
2370 if ((cc_status.value1 != 0
2371 && rtx_equal_p (SET_SRC (set), cc_status.value1))
2372 || (cc_status.value2 != 0
2373 && rtx_equal_p (SET_SRC (set), cc_status.value2)))
2375 /* Don't delete insn if it has an addressing side-effect. */
2376 if (! FIND_REG_INC_NOTE (insn, NULL_RTX)
2377 /* or if anything in it is volatile. */
2378 && ! volatile_refs_p (PATTERN (insn)))
2380 /* We don't really delete the insn; just ignore it. */
2381 last_ignored_compare = insn;
2382 break;
2387 #endif
2389 #ifndef STACK_REGS
2390 /* Don't bother outputting obvious no-ops, even without -O.
2391 This optimization is fast and doesn't interfere with debugging.
2392 Don't do this if the insn is in a delay slot, since this
2393 will cause an improper number of delay insns to be written. */
2394 if (final_sequence == 0
2395 && prescan >= 0
2396 && GET_CODE (insn) == INSN && GET_CODE (body) == SET
2397 && GET_CODE (SET_SRC (body)) == REG
2398 && GET_CODE (SET_DEST (body)) == REG
2399 && REGNO (SET_SRC (body)) == REGNO (SET_DEST (body)))
2400 break;
2401 #endif
2403 #ifdef HAVE_cc0
2404 /* If this is a conditional branch, maybe modify it
2405 if the cc's are in a nonstandard state
2406 so that it accomplishes the same thing that it would
2407 do straightforwardly if the cc's were set up normally. */
2409 if (cc_status.flags != 0
2410 && GET_CODE (insn) == JUMP_INSN
2411 && GET_CODE (body) == SET
2412 && SET_DEST (body) == pc_rtx
2413 && GET_CODE (SET_SRC (body)) == IF_THEN_ELSE
2414 && GET_RTX_CLASS (GET_CODE (XEXP (SET_SRC (body), 0))) == '<'
2415 && XEXP (XEXP (SET_SRC (body), 0), 0) == cc0_rtx
2416 /* This is done during prescan; it is not done again
2417 in final scan when prescan has been done. */
2418 && prescan >= 0)
2420 /* This function may alter the contents of its argument
2421 and clear some of the cc_status.flags bits.
2422 It may also return 1 meaning condition now always true
2423 or -1 meaning condition now always false
2424 or 2 meaning condition nontrivial but altered. */
2425 int result = alter_cond (XEXP (SET_SRC (body), 0));
2426 /* If condition now has fixed value, replace the IF_THEN_ELSE
2427 with its then-operand or its else-operand. */
2428 if (result == 1)
2429 SET_SRC (body) = XEXP (SET_SRC (body), 1);
2430 if (result == -1)
2431 SET_SRC (body) = XEXP (SET_SRC (body), 2);
2433 /* The jump is now either unconditional or a no-op.
2434 If it has become a no-op, don't try to output it.
2435 (It would not be recognized.) */
2436 if (SET_SRC (body) == pc_rtx)
2438 delete_insn (insn);
2439 break;
2441 else if (GET_CODE (SET_SRC (body)) == RETURN)
2442 /* Replace (set (pc) (return)) with (return). */
2443 PATTERN (insn) = body = SET_SRC (body);
2445 /* Rerecognize the instruction if it has changed. */
2446 if (result != 0)
2447 INSN_CODE (insn) = -1;
2450 /* Make same adjustments to instructions that examine the
2451 condition codes without jumping and instructions that
2452 handle conditional moves (if this machine has either one). */
2454 if (cc_status.flags != 0
2455 && set != 0)
2457 rtx cond_rtx, then_rtx, else_rtx;
2459 if (GET_CODE (insn) != JUMP_INSN
2460 && GET_CODE (SET_SRC (set)) == IF_THEN_ELSE)
2462 cond_rtx = XEXP (SET_SRC (set), 0);
2463 then_rtx = XEXP (SET_SRC (set), 1);
2464 else_rtx = XEXP (SET_SRC (set), 2);
2466 else
2468 cond_rtx = SET_SRC (set);
2469 then_rtx = const_true_rtx;
2470 else_rtx = const0_rtx;
2473 switch (GET_CODE (cond_rtx))
2475 case GTU:
2476 case GT:
2477 case LTU:
2478 case LT:
2479 case GEU:
2480 case GE:
2481 case LEU:
2482 case LE:
2483 case EQ:
2484 case NE:
2486 int result;
2487 if (XEXP (cond_rtx, 0) != cc0_rtx)
2488 break;
2489 result = alter_cond (cond_rtx);
2490 if (result == 1)
2491 validate_change (insn, &SET_SRC (set), then_rtx, 0);
2492 else if (result == -1)
2493 validate_change (insn, &SET_SRC (set), else_rtx, 0);
2494 else if (result == 2)
2495 INSN_CODE (insn) = -1;
2496 if (SET_DEST (set) == SET_SRC (set))
2497 delete_insn (insn);
2499 break;
2501 default:
2502 break;
2506 #endif
2508 #ifdef HAVE_peephole
2509 /* Do machine-specific peephole optimizations if desired. */
2511 if (optimize && !flag_no_peephole && !nopeepholes)
2513 rtx next = peephole (insn);
2514 /* When peepholing, if there were notes within the peephole,
2515 emit them before the peephole. */
2516 if (next != 0 && next != NEXT_INSN (insn))
2518 rtx prev = PREV_INSN (insn);
2520 for (note = NEXT_INSN (insn); note != next;
2521 note = NEXT_INSN (note))
2522 final_scan_insn (note, file, optimize, prescan, nopeepholes);
2524 /* In case this is prescan, put the notes
2525 in proper position for later rescan. */
2526 note = NEXT_INSN (insn);
2527 PREV_INSN (note) = prev;
2528 NEXT_INSN (prev) = note;
2529 NEXT_INSN (PREV_INSN (next)) = insn;
2530 PREV_INSN (insn) = PREV_INSN (next);
2531 NEXT_INSN (insn) = next;
2532 PREV_INSN (next) = insn;
2535 /* PEEPHOLE might have changed this. */
2536 body = PATTERN (insn);
2538 #endif
2540 /* Try to recognize the instruction.
2541 If successful, verify that the operands satisfy the
2542 constraints for the instruction. Crash if they don't,
2543 since `reload' should have changed them so that they do. */
2545 insn_code_number = recog_memoized (insn);
2546 cleanup_subreg_operands (insn);
2548 /* Dump the insn in the assembly for debugging. */
2549 if (flag_dump_rtl_in_asm)
2551 print_rtx_head = ASM_COMMENT_START;
2552 print_rtl_single (asm_out_file, insn);
2553 print_rtx_head = "";
2556 if (! constrain_operands_cached (1))
2557 fatal_insn_not_found (insn);
2559 /* Some target machines need to prescan each insn before
2560 it is output. */
2562 #ifdef FINAL_PRESCAN_INSN
2563 FINAL_PRESCAN_INSN (insn, recog_data.operand, recog_data.n_operands);
2564 #endif
2566 #ifdef HAVE_conditional_execution
2567 if (GET_CODE (PATTERN (insn)) == COND_EXEC)
2568 current_insn_predicate = COND_EXEC_TEST (PATTERN (insn));
2569 else
2570 current_insn_predicate = NULL_RTX;
2571 #endif
2573 #ifdef HAVE_cc0
2574 cc_prev_status = cc_status;
2576 /* Update `cc_status' for this instruction.
2577 The instruction's output routine may change it further.
2578 If the output routine for a jump insn needs to depend
2579 on the cc status, it should look at cc_prev_status. */
2581 NOTICE_UPDATE_CC (body, insn);
2582 #endif
2584 current_output_insn = debug_insn = insn;
2586 #if defined (DWARF2_UNWIND_INFO)
2587 if (GET_CODE (insn) == CALL_INSN && dwarf2out_do_frame ())
2588 dwarf2out_frame_debug (insn);
2589 #endif
2591 /* Find the proper template for this insn. */
2592 template = get_insn_template (insn_code_number, insn);
2594 /* If the C code returns 0, it means that it is a jump insn
2595 which follows a deleted test insn, and that test insn
2596 needs to be reinserted. */
2597 if (template == 0)
2599 rtx prev;
2601 if (prev_nonnote_insn (insn) != last_ignored_compare)
2602 abort ();
2603 new_block = 0;
2605 /* We have already processed the notes between the setter and
2606 the user. Make sure we don't process them again, this is
2607 particularly important if one of the notes is a block
2608 scope note or an EH note. */
2609 for (prev = insn;
2610 prev != last_ignored_compare;
2611 prev = PREV_INSN (prev))
2613 if (GET_CODE (prev) == NOTE)
2614 delete_insn (prev); /* Use delete_note. */
2617 return prev;
2620 /* If the template is the string "#", it means that this insn must
2621 be split. */
2622 if (template[0] == '#' && template[1] == '\0')
2624 rtx new = try_split (body, insn, 0);
2626 /* If we didn't split the insn, go away. */
2627 if (new == insn && PATTERN (new) == body)
2628 fatal_insn ("could not split insn", insn);
2630 #ifdef HAVE_ATTR_length
2631 /* This instruction should have been split in shorten_branches,
2632 to ensure that we would have valid length info for the
2633 splitees. */
2634 abort ();
2635 #endif
2637 new_block = 0;
2638 return new;
2641 if (prescan > 0)
2642 break;
2644 #ifdef IA64_UNWIND_INFO
2645 IA64_UNWIND_EMIT (asm_out_file, insn);
2646 #endif
2647 /* Output assembler code from the template. */
2649 output_asm_insn (template, recog_data.operand);
2651 #if defined (DWARF2_UNWIND_INFO)
2652 #if defined (HAVE_prologue)
2653 if (GET_CODE (insn) == INSN && dwarf2out_do_frame ())
2654 dwarf2out_frame_debug (insn);
2655 #else
2656 if (!ACCUMULATE_OUTGOING_ARGS
2657 && GET_CODE (insn) == INSN
2658 && dwarf2out_do_frame ())
2659 dwarf2out_frame_debug (insn);
2660 #endif
2661 #endif
2663 #if 0
2664 /* It's not at all clear why we did this and doing so interferes
2665 with tests we'd like to do to use REG_WAS_0 notes, so let's try
2666 with this out. */
2668 /* Mark this insn as having been output. */
2669 INSN_DELETED_P (insn) = 1;
2670 #endif
2672 /* Emit information for vtable gc. */
2673 note = find_reg_note (insn, REG_VTABLE_REF, NULL_RTX);
2674 if (note)
2675 assemble_vtable_entry (XEXP (XEXP (note, 0), 0),
2676 INTVAL (XEXP (XEXP (note, 0), 1)));
2678 current_output_insn = debug_insn = 0;
2681 return NEXT_INSN (insn);
2684 /* Output debugging info to the assembler file FILE
2685 based on the NOTE-insn INSN, assumed to be a line number. */
2687 static void
2688 notice_source_line (insn)
2689 rtx insn;
2691 const char *filename = NOTE_SOURCE_FILE (insn);
2693 last_filename = filename;
2694 last_linenum = NOTE_LINE_NUMBER (insn);
2695 high_block_linenum = MAX (last_linenum, high_block_linenum);
2696 high_function_linenum = MAX (last_linenum, high_function_linenum);
2699 /* For each operand in INSN, simplify (subreg (reg)) so that it refers
2700 directly to the desired hard register. */
2702 void
2703 cleanup_subreg_operands (insn)
2704 rtx insn;
2706 int i;
2707 extract_insn_cached (insn);
2708 for (i = 0; i < recog_data.n_operands; i++)
2710 /* The following test cannot use recog_data.operand when tesing
2711 for a SUBREG: the underlying object might have been changed
2712 already if we are inside a match_operator expression that
2713 matches the else clause. Instead we test the underlying
2714 expression directly. */
2715 if (GET_CODE (*recog_data.operand_loc[i]) == SUBREG)
2716 recog_data.operand[i] = alter_subreg (recog_data.operand_loc[i]);
2717 else if (GET_CODE (recog_data.operand[i]) == PLUS
2718 || GET_CODE (recog_data.operand[i]) == MULT
2719 || GET_CODE (recog_data.operand[i]) == MEM)
2720 recog_data.operand[i] = walk_alter_subreg (recog_data.operand_loc[i]);
2723 for (i = 0; i < recog_data.n_dups; i++)
2725 if (GET_CODE (*recog_data.dup_loc[i]) == SUBREG)
2726 *recog_data.dup_loc[i] = alter_subreg (recog_data.dup_loc[i]);
2727 else if (GET_CODE (*recog_data.dup_loc[i]) == PLUS
2728 || GET_CODE (*recog_data.dup_loc[i]) == MULT
2729 || GET_CODE (*recog_data.dup_loc[i]) == MEM)
2730 *recog_data.dup_loc[i] = walk_alter_subreg (recog_data.dup_loc[i]);
2734 /* If X is a SUBREG, replace it with a REG or a MEM,
2735 based on the thing it is a subreg of. */
2738 alter_subreg (xp)
2739 rtx *xp;
2741 rtx x = *xp;
2742 rtx y = SUBREG_REG (x);
2744 /* simplify_subreg does not remove subreg from volatile references.
2745 We are required to. */
2746 if (GET_CODE (y) == MEM)
2747 *xp = adjust_address (y, GET_MODE (x), SUBREG_BYTE (x));
2748 else
2750 rtx new = simplify_subreg (GET_MODE (x), y, GET_MODE (y),
2751 SUBREG_BYTE (x));
2753 if (new != 0)
2754 *xp = new;
2755 /* Simplify_subreg can't handle some REG cases, but we have to. */
2756 else if (GET_CODE (y) == REG)
2758 unsigned int regno = subreg_hard_regno (x, 1);
2759 PUT_CODE (x, REG);
2760 REGNO (x) = regno;
2761 ORIGINAL_REGNO (x) = ORIGINAL_REGNO (y);
2762 /* This field has a different meaning for REGs and SUBREGs. Make
2763 sure to clear it! */
2764 x->used = 0;
2766 else
2767 abort ();
2770 return *xp;
2773 /* Do alter_subreg on all the SUBREGs contained in X. */
2775 static rtx
2776 walk_alter_subreg (xp)
2777 rtx *xp;
2779 rtx x = *xp;
2780 switch (GET_CODE (x))
2782 case PLUS:
2783 case MULT:
2784 XEXP (x, 0) = walk_alter_subreg (&XEXP (x, 0));
2785 XEXP (x, 1) = walk_alter_subreg (&XEXP (x, 1));
2786 break;
2788 case MEM:
2789 XEXP (x, 0) = walk_alter_subreg (&XEXP (x, 0));
2790 break;
2792 case SUBREG:
2793 return alter_subreg (xp);
2795 default:
2796 break;
2799 return *xp;
2802 #ifdef HAVE_cc0
2804 /* Given BODY, the body of a jump instruction, alter the jump condition
2805 as required by the bits that are set in cc_status.flags.
2806 Not all of the bits there can be handled at this level in all cases.
2808 The value is normally 0.
2809 1 means that the condition has become always true.
2810 -1 means that the condition has become always false.
2811 2 means that COND has been altered. */
2813 static int
2814 alter_cond (cond)
2815 rtx cond;
2817 int value = 0;
2819 if (cc_status.flags & CC_REVERSED)
2821 value = 2;
2822 PUT_CODE (cond, swap_condition (GET_CODE (cond)));
2825 if (cc_status.flags & CC_INVERTED)
2827 value = 2;
2828 PUT_CODE (cond, reverse_condition (GET_CODE (cond)));
2831 if (cc_status.flags & CC_NOT_POSITIVE)
2832 switch (GET_CODE (cond))
2834 case LE:
2835 case LEU:
2836 case GEU:
2837 /* Jump becomes unconditional. */
2838 return 1;
2840 case GT:
2841 case GTU:
2842 case LTU:
2843 /* Jump becomes no-op. */
2844 return -1;
2846 case GE:
2847 PUT_CODE (cond, EQ);
2848 value = 2;
2849 break;
2851 case LT:
2852 PUT_CODE (cond, NE);
2853 value = 2;
2854 break;
2856 default:
2857 break;
2860 if (cc_status.flags & CC_NOT_NEGATIVE)
2861 switch (GET_CODE (cond))
2863 case GE:
2864 case GEU:
2865 /* Jump becomes unconditional. */
2866 return 1;
2868 case LT:
2869 case LTU:
2870 /* Jump becomes no-op. */
2871 return -1;
2873 case LE:
2874 case LEU:
2875 PUT_CODE (cond, EQ);
2876 value = 2;
2877 break;
2879 case GT:
2880 case GTU:
2881 PUT_CODE (cond, NE);
2882 value = 2;
2883 break;
2885 default:
2886 break;
2889 if (cc_status.flags & CC_NO_OVERFLOW)
2890 switch (GET_CODE (cond))
2892 case GEU:
2893 /* Jump becomes unconditional. */
2894 return 1;
2896 case LEU:
2897 PUT_CODE (cond, EQ);
2898 value = 2;
2899 break;
2901 case GTU:
2902 PUT_CODE (cond, NE);
2903 value = 2;
2904 break;
2906 case LTU:
2907 /* Jump becomes no-op. */
2908 return -1;
2910 default:
2911 break;
2914 if (cc_status.flags & (CC_Z_IN_NOT_N | CC_Z_IN_N))
2915 switch (GET_CODE (cond))
2917 default:
2918 abort ();
2920 case NE:
2921 PUT_CODE (cond, cc_status.flags & CC_Z_IN_N ? GE : LT);
2922 value = 2;
2923 break;
2925 case EQ:
2926 PUT_CODE (cond, cc_status.flags & CC_Z_IN_N ? LT : GE);
2927 value = 2;
2928 break;
2931 if (cc_status.flags & CC_NOT_SIGNED)
2932 /* The flags are valid if signed condition operators are converted
2933 to unsigned. */
2934 switch (GET_CODE (cond))
2936 case LE:
2937 PUT_CODE (cond, LEU);
2938 value = 2;
2939 break;
2941 case LT:
2942 PUT_CODE (cond, LTU);
2943 value = 2;
2944 break;
2946 case GT:
2947 PUT_CODE (cond, GTU);
2948 value = 2;
2949 break;
2951 case GE:
2952 PUT_CODE (cond, GEU);
2953 value = 2;
2954 break;
2956 default:
2957 break;
2960 return value;
2962 #endif
2964 /* Report inconsistency between the assembler template and the operands.
2965 In an `asm', it's the user's fault; otherwise, the compiler's fault. */
2967 void
2968 output_operand_lossage (msgid)
2969 const char *msgid;
2971 if (this_is_asm_operands)
2972 error_for_asm (this_is_asm_operands, "invalid `asm': %s", _(msgid));
2973 else
2974 internal_error ("output_operand: %s", _(msgid));
2977 /* Output of assembler code from a template, and its subroutines. */
2979 /* Annotate the assembly with a comment describing the pattern and
2980 alternative used. */
2982 static void
2983 output_asm_name ()
2985 if (debug_insn)
2987 int num = INSN_CODE (debug_insn);
2988 fprintf (asm_out_file, "\t%s %d\t%s",
2989 ASM_COMMENT_START, INSN_UID (debug_insn),
2990 insn_data[num].name);
2991 if (insn_data[num].n_alternatives > 1)
2992 fprintf (asm_out_file, "/%d", which_alternative + 1);
2993 #ifdef HAVE_ATTR_length
2994 fprintf (asm_out_file, "\t[length = %d]",
2995 get_attr_length (debug_insn));
2996 #endif
2997 /* Clear this so only the first assembler insn
2998 of any rtl insn will get the special comment for -dp. */
2999 debug_insn = 0;
3003 /* If OP is a REG or MEM and we can find a MEM_EXPR corresponding to it
3004 or its address, return that expr . Set *PADDRESSP to 1 if the expr
3005 corresponds to the address of the object and 0 if to the object. */
3007 static tree
3008 get_mem_expr_from_op (op, paddressp)
3009 rtx op;
3010 int *paddressp;
3012 tree expr;
3013 int inner_addressp;
3015 *paddressp = 0;
3017 if (GET_CODE (op) == REG && ORIGINAL_REGNO (op) >= FIRST_PSEUDO_REGISTER)
3018 return REGNO_DECL (ORIGINAL_REGNO (op));
3019 else if (GET_CODE (op) != MEM)
3020 return 0;
3022 if (MEM_EXPR (op) != 0)
3023 return MEM_EXPR (op);
3025 /* Otherwise we have an address, so indicate it and look at the address. */
3026 *paddressp = 1;
3027 op = XEXP (op, 0);
3029 /* First check if we have a decl for the address, then look at the right side
3030 if it is a PLUS. Otherwise, strip off arithmetic and keep looking.
3031 But don't allow the address to itself be indirect. */
3032 if ((expr = get_mem_expr_from_op (op, &inner_addressp)) && ! inner_addressp)
3033 return expr;
3034 else if (GET_CODE (op) == PLUS
3035 && (expr = get_mem_expr_from_op (XEXP (op, 1), &inner_addressp)))
3036 return expr;
3038 while (GET_RTX_CLASS (GET_CODE (op)) == '1'
3039 || GET_RTX_CLASS (GET_CODE (op)) == '2')
3040 op = XEXP (op, 0);
3042 expr = get_mem_expr_from_op (op, &inner_addressp);
3043 return inner_addressp ? 0 : expr;
3046 /* Output operand names for assembler instructions. OPERANDS is the
3047 operand vector, OPORDER is the order to write the operands, and NOPS
3048 is the number of operands to write. */
3050 static void
3051 output_asm_operand_names (operands, oporder, nops)
3052 rtx *operands;
3053 int *oporder;
3054 int nops;
3056 int wrote = 0;
3057 int i;
3059 for (i = 0; i < nops; i++)
3061 int addressp;
3062 tree expr = get_mem_expr_from_op (operands[oporder[i]], &addressp);
3064 if (expr)
3066 fprintf (asm_out_file, "%c%s %s",
3067 wrote ? ',' : '\t', wrote ? "" : ASM_COMMENT_START,
3068 addressp ? "*" : "");
3069 print_mem_expr (asm_out_file, expr);
3070 wrote = 1;
3075 /* Output text from TEMPLATE to the assembler output file,
3076 obeying %-directions to substitute operands taken from
3077 the vector OPERANDS.
3079 %N (for N a digit) means print operand N in usual manner.
3080 %lN means require operand N to be a CODE_LABEL or LABEL_REF
3081 and print the label name with no punctuation.
3082 %cN means require operand N to be a constant
3083 and print the constant expression with no punctuation.
3084 %aN means expect operand N to be a memory address
3085 (not a memory reference!) and print a reference
3086 to that address.
3087 %nN means expect operand N to be a constant
3088 and print a constant expression for minus the value
3089 of the operand, with no other punctuation. */
3091 void
3092 output_asm_insn (template, operands)
3093 const char *template;
3094 rtx *operands;
3096 const char *p;
3097 int c;
3098 #ifdef ASSEMBLER_DIALECT
3099 int dialect = 0;
3100 #endif
3101 int oporder[MAX_RECOG_OPERANDS];
3102 char opoutput[MAX_RECOG_OPERANDS];
3103 int ops = 0;
3105 /* An insn may return a null string template
3106 in a case where no assembler code is needed. */
3107 if (*template == 0)
3108 return;
3110 memset (opoutput, 0, sizeof opoutput);
3111 p = template;
3112 putc ('\t', asm_out_file);
3114 #ifdef ASM_OUTPUT_OPCODE
3115 ASM_OUTPUT_OPCODE (asm_out_file, p);
3116 #endif
3118 while ((c = *p++))
3119 switch (c)
3121 case '\n':
3122 if (flag_verbose_asm)
3123 output_asm_operand_names (operands, oporder, ops);
3124 if (flag_print_asm_name)
3125 output_asm_name ();
3127 ops = 0;
3128 memset (opoutput, 0, sizeof opoutput);
3130 putc (c, asm_out_file);
3131 #ifdef ASM_OUTPUT_OPCODE
3132 while ((c = *p) == '\t')
3134 putc (c, asm_out_file);
3135 p++;
3137 ASM_OUTPUT_OPCODE (asm_out_file, p);
3138 #endif
3139 break;
3141 #ifdef ASSEMBLER_DIALECT
3142 case '{':
3144 int i;
3146 if (dialect)
3147 output_operand_lossage ("nested assembly dialect alternatives");
3148 else
3149 dialect = 1;
3151 /* If we want the first dialect, do nothing. Otherwise, skip
3152 DIALECT_NUMBER of strings ending with '|'. */
3153 for (i = 0; i < dialect_number; i++)
3155 while (*p && *p != '}' && *p++ != '|')
3157 if (*p == '}')
3158 break;
3159 if (*p == '|')
3160 p++;
3163 if (*p == '\0')
3164 output_operand_lossage ("unterminated assembly dialect alternative");
3166 break;
3168 case '|':
3169 if (dialect)
3171 /* Skip to close brace. */
3174 if (*p == '\0')
3176 output_operand_lossage ("unterminated assembly dialect alternative");
3177 break;
3180 while (*p++ != '}');
3181 dialect = 0;
3183 else
3184 putc (c, asm_out_file);
3185 break;
3187 case '}':
3188 if (! dialect)
3189 putc (c, asm_out_file);
3190 dialect = 0;
3191 break;
3192 #endif
3194 case '%':
3195 /* %% outputs a single %. */
3196 if (*p == '%')
3198 p++;
3199 putc (c, asm_out_file);
3201 /* %= outputs a number which is unique to each insn in the entire
3202 compilation. This is useful for making local labels that are
3203 referred to more than once in a given insn. */
3204 else if (*p == '=')
3206 p++;
3207 fprintf (asm_out_file, "%d", insn_counter);
3209 /* % followed by a letter and some digits
3210 outputs an operand in a special way depending on the letter.
3211 Letters `acln' are implemented directly.
3212 Other letters are passed to `output_operand' so that
3213 the PRINT_OPERAND macro can define them. */
3214 else if (ISALPHA (*p))
3216 int letter = *p++;
3217 c = atoi (p);
3219 if (! ISDIGIT (*p))
3220 output_operand_lossage ("operand number missing after %-letter");
3221 else if (this_is_asm_operands
3222 && (c < 0 || (unsigned int) c >= insn_noperands))
3223 output_operand_lossage ("operand number out of range");
3224 else if (letter == 'l')
3225 output_asm_label (operands[c]);
3226 else if (letter == 'a')
3227 output_address (operands[c]);
3228 else if (letter == 'c')
3230 if (CONSTANT_ADDRESS_P (operands[c]))
3231 output_addr_const (asm_out_file, operands[c]);
3232 else
3233 output_operand (operands[c], 'c');
3235 else if (letter == 'n')
3237 if (GET_CODE (operands[c]) == CONST_INT)
3238 fprintf (asm_out_file, HOST_WIDE_INT_PRINT_DEC,
3239 - INTVAL (operands[c]));
3240 else
3242 putc ('-', asm_out_file);
3243 output_addr_const (asm_out_file, operands[c]);
3246 else
3247 output_operand (operands[c], letter);
3249 if (!opoutput[c])
3250 oporder[ops++] = c;
3251 opoutput[c] = 1;
3253 while (ISDIGIT (c = *p))
3254 p++;
3256 /* % followed by a digit outputs an operand the default way. */
3257 else if (ISDIGIT (*p))
3259 c = atoi (p);
3260 if (this_is_asm_operands
3261 && (c < 0 || (unsigned int) c >= insn_noperands))
3262 output_operand_lossage ("operand number out of range");
3263 else
3264 output_operand (operands[c], 0);
3266 if (!opoutput[c])
3267 oporder[ops++] = c;
3268 opoutput[c] = 1;
3270 while (ISDIGIT (c = *p))
3271 p++;
3273 /* % followed by punctuation: output something for that
3274 punctuation character alone, with no operand.
3275 The PRINT_OPERAND macro decides what is actually done. */
3276 #ifdef PRINT_OPERAND_PUNCT_VALID_P
3277 else if (PRINT_OPERAND_PUNCT_VALID_P ((unsigned char) *p))
3278 output_operand (NULL_RTX, *p++);
3279 #endif
3280 else
3281 output_operand_lossage ("invalid %%-code");
3282 break;
3284 default:
3285 putc (c, asm_out_file);
3288 /* Write out the variable names for operands, if we know them. */
3289 if (flag_verbose_asm)
3290 output_asm_operand_names (operands, oporder, ops);
3291 if (flag_print_asm_name)
3292 output_asm_name ();
3294 putc ('\n', asm_out_file);
3297 /* Output a LABEL_REF, or a bare CODE_LABEL, as an assembler symbol. */
3299 void
3300 output_asm_label (x)
3301 rtx x;
3303 char buf[256];
3305 if (GET_CODE (x) == LABEL_REF)
3306 x = XEXP (x, 0);
3307 if (GET_CODE (x) == CODE_LABEL
3308 || (GET_CODE (x) == NOTE
3309 && NOTE_LINE_NUMBER (x) == NOTE_INSN_DELETED_LABEL))
3310 ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
3311 else
3312 output_operand_lossage ("`%l' operand isn't a label");
3314 assemble_name (asm_out_file, buf);
3317 /* Print operand X using machine-dependent assembler syntax.
3318 The macro PRINT_OPERAND is defined just to control this function.
3319 CODE is a non-digit that preceded the operand-number in the % spec,
3320 such as 'z' if the spec was `%z3'. CODE is 0 if there was no char
3321 between the % and the digits.
3322 When CODE is a non-letter, X is 0.
3324 The meanings of the letters are machine-dependent and controlled
3325 by PRINT_OPERAND. */
3327 static void
3328 output_operand (x, code)
3329 rtx x;
3330 int code ATTRIBUTE_UNUSED;
3332 if (x && GET_CODE (x) == SUBREG)
3333 x = alter_subreg (&x);
3335 /* If X is a pseudo-register, abort now rather than writing trash to the
3336 assembler file. */
3338 if (x && GET_CODE (x) == REG && REGNO (x) >= FIRST_PSEUDO_REGISTER)
3339 abort ();
3341 PRINT_OPERAND (asm_out_file, x, code);
3344 /* Print a memory reference operand for address X
3345 using machine-dependent assembler syntax.
3346 The macro PRINT_OPERAND_ADDRESS exists just to control this function. */
3348 void
3349 output_address (x)
3350 rtx x;
3352 walk_alter_subreg (&x);
3353 PRINT_OPERAND_ADDRESS (asm_out_file, x);
3356 /* Print an integer constant expression in assembler syntax.
3357 Addition and subtraction are the only arithmetic
3358 that may appear in these expressions. */
3360 void
3361 output_addr_const (file, x)
3362 FILE *file;
3363 rtx x;
3365 char buf[256];
3367 restart:
3368 switch (GET_CODE (x))
3370 case PC:
3371 putc ('.', file);
3372 break;
3374 case SYMBOL_REF:
3375 #ifdef ASM_OUTPUT_SYMBOL_REF
3376 ASM_OUTPUT_SYMBOL_REF (file, x);
3377 #else
3378 assemble_name (file, XSTR (x, 0));
3379 #endif
3380 break;
3382 case LABEL_REF:
3383 x = XEXP (x, 0);
3384 /* Fall through. */
3385 case CODE_LABEL:
3386 ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
3387 #ifdef ASM_OUTPUT_LABEL_REF
3388 ASM_OUTPUT_LABEL_REF (file, buf);
3389 #else
3390 assemble_name (file, buf);
3391 #endif
3392 break;
3394 case CONST_INT:
3395 fprintf (file, HOST_WIDE_INT_PRINT_DEC, INTVAL (x));
3396 break;
3398 case CONST:
3399 /* This used to output parentheses around the expression,
3400 but that does not work on the 386 (either ATT or BSD assembler). */
3401 output_addr_const (file, XEXP (x, 0));
3402 break;
3404 case CONST_DOUBLE:
3405 if (GET_MODE (x) == VOIDmode)
3407 /* We can use %d if the number is one word and positive. */
3408 if (CONST_DOUBLE_HIGH (x))
3409 fprintf (file, HOST_WIDE_INT_PRINT_DOUBLE_HEX,
3410 CONST_DOUBLE_HIGH (x), CONST_DOUBLE_LOW (x));
3411 else if (CONST_DOUBLE_LOW (x) < 0)
3412 fprintf (file, HOST_WIDE_INT_PRINT_HEX, CONST_DOUBLE_LOW (x));
3413 else
3414 fprintf (file, HOST_WIDE_INT_PRINT_DEC, CONST_DOUBLE_LOW (x));
3416 else
3417 /* We can't handle floating point constants;
3418 PRINT_OPERAND must handle them. */
3419 output_operand_lossage ("floating constant misused");
3420 break;
3422 case PLUS:
3423 /* Some assemblers need integer constants to appear last (eg masm). */
3424 if (GET_CODE (XEXP (x, 0)) == CONST_INT)
3426 output_addr_const (file, XEXP (x, 1));
3427 if (INTVAL (XEXP (x, 0)) >= 0)
3428 fprintf (file, "+");
3429 output_addr_const (file, XEXP (x, 0));
3431 else
3433 output_addr_const (file, XEXP (x, 0));
3434 if (GET_CODE (XEXP (x, 1)) != CONST_INT
3435 || INTVAL (XEXP (x, 1)) >= 0)
3436 fprintf (file, "+");
3437 output_addr_const (file, XEXP (x, 1));
3439 break;
3441 case MINUS:
3442 /* Avoid outputting things like x-x or x+5-x,
3443 since some assemblers can't handle that. */
3444 x = simplify_subtraction (x);
3445 if (GET_CODE (x) != MINUS)
3446 goto restart;
3448 output_addr_const (file, XEXP (x, 0));
3449 fprintf (file, "-");
3450 if ((GET_CODE (XEXP (x, 1)) == CONST_INT && INTVAL (XEXP (x, 1)) >= 0)
3451 || GET_CODE (XEXP (x, 1)) == PC
3452 || GET_CODE (XEXP (x, 1)) == SYMBOL_REF)
3453 output_addr_const (file, XEXP (x, 1));
3454 else
3456 fputs (targetm.asm_out.open_paren, file);
3457 output_addr_const (file, XEXP (x, 1));
3458 fputs (targetm.asm_out.close_paren, file);
3460 break;
3462 case ZERO_EXTEND:
3463 case SIGN_EXTEND:
3464 case SUBREG:
3465 output_addr_const (file, XEXP (x, 0));
3466 break;
3468 default:
3469 #ifdef OUTPUT_ADDR_CONST_EXTRA
3470 OUTPUT_ADDR_CONST_EXTRA (file, x, fail);
3471 break;
3473 fail:
3474 #endif
3475 output_operand_lossage ("invalid expression as operand");
3479 /* A poor man's fprintf, with the added features of %I, %R, %L, and %U.
3480 %R prints the value of REGISTER_PREFIX.
3481 %L prints the value of LOCAL_LABEL_PREFIX.
3482 %U prints the value of USER_LABEL_PREFIX.
3483 %I prints the value of IMMEDIATE_PREFIX.
3484 %O runs ASM_OUTPUT_OPCODE to transform what follows in the string.
3485 Also supported are %d, %x, %s, %e, %f, %g and %%.
3487 We handle alternate assembler dialects here, just like output_asm_insn. */
3489 void
3490 asm_fprintf VPARAMS ((FILE *file, const char *p, ...))
3492 char buf[10];
3493 char *q, c;
3495 VA_OPEN (argptr, p);
3496 VA_FIXEDARG (argptr, FILE *, file);
3497 VA_FIXEDARG (argptr, const char *, p);
3499 buf[0] = '%';
3501 while ((c = *p++))
3502 switch (c)
3504 #ifdef ASSEMBLER_DIALECT
3505 case '{':
3507 int i;
3509 /* If we want the first dialect, do nothing. Otherwise, skip
3510 DIALECT_NUMBER of strings ending with '|'. */
3511 for (i = 0; i < dialect_number; i++)
3513 while (*p && *p++ != '|')
3516 if (*p == '|')
3517 p++;
3520 break;
3522 case '|':
3523 /* Skip to close brace. */
3524 while (*p && *p++ != '}')
3526 break;
3528 case '}':
3529 break;
3530 #endif
3532 case '%':
3533 c = *p++;
3534 q = &buf[1];
3535 while (ISDIGIT (c) || c == '.')
3537 *q++ = c;
3538 c = *p++;
3540 switch (c)
3542 case '%':
3543 fprintf (file, "%%");
3544 break;
3546 case 'd': case 'i': case 'u':
3547 case 'x': case 'p': case 'X':
3548 case 'o':
3549 *q++ = c;
3550 *q = 0;
3551 fprintf (file, buf, va_arg (argptr, int));
3552 break;
3554 case 'w':
3555 /* This is a prefix to the 'd', 'i', 'u', 'x', 'p', and 'X' cases,
3556 but we do not check for those cases. It means that the value
3557 is a HOST_WIDE_INT, which may be either `int' or `long'. */
3559 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
3560 #else
3561 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
3562 *q++ = 'l';
3563 #else
3564 *q++ = 'l';
3565 *q++ = 'l';
3566 #endif
3567 #endif
3569 *q++ = *p++;
3570 *q = 0;
3571 fprintf (file, buf, va_arg (argptr, HOST_WIDE_INT));
3572 break;
3574 case 'l':
3575 *q++ = c;
3576 *q++ = *p++;
3577 *q = 0;
3578 fprintf (file, buf, va_arg (argptr, long));
3579 break;
3581 case 'e':
3582 case 'f':
3583 case 'g':
3584 *q++ = c;
3585 *q = 0;
3586 fprintf (file, buf, va_arg (argptr, double));
3587 break;
3589 case 's':
3590 *q++ = c;
3591 *q = 0;
3592 fprintf (file, buf, va_arg (argptr, char *));
3593 break;
3595 case 'O':
3596 #ifdef ASM_OUTPUT_OPCODE
3597 ASM_OUTPUT_OPCODE (asm_out_file, p);
3598 #endif
3599 break;
3601 case 'R':
3602 #ifdef REGISTER_PREFIX
3603 fprintf (file, "%s", REGISTER_PREFIX);
3604 #endif
3605 break;
3607 case 'I':
3608 #ifdef IMMEDIATE_PREFIX
3609 fprintf (file, "%s", IMMEDIATE_PREFIX);
3610 #endif
3611 break;
3613 case 'L':
3614 #ifdef LOCAL_LABEL_PREFIX
3615 fprintf (file, "%s", LOCAL_LABEL_PREFIX);
3616 #endif
3617 break;
3619 case 'U':
3620 fputs (user_label_prefix, file);
3621 break;
3623 #ifdef ASM_FPRINTF_EXTENSIONS
3624 /* Upper case letters are reserved for general use by asm_fprintf
3625 and so are not available to target specific code. In order to
3626 prevent the ASM_FPRINTF_EXTENSIONS macro from using them then,
3627 they are defined here. As they get turned into real extensions
3628 to asm_fprintf they should be removed from this list. */
3629 case 'A': case 'B': case 'C': case 'D': case 'E':
3630 case 'F': case 'G': case 'H': case 'J': case 'K':
3631 case 'M': case 'N': case 'P': case 'Q': case 'S':
3632 case 'T': case 'V': case 'W': case 'Y': case 'Z':
3633 break;
3635 ASM_FPRINTF_EXTENSIONS (file, argptr, p)
3636 #endif
3637 default:
3638 abort ();
3640 break;
3642 default:
3643 fputc (c, file);
3645 VA_CLOSE (argptr);
3648 /* Split up a CONST_DOUBLE or integer constant rtx
3649 into two rtx's for single words,
3650 storing in *FIRST the word that comes first in memory in the target
3651 and in *SECOND the other. */
3653 void
3654 split_double (value, first, second)
3655 rtx value;
3656 rtx *first, *second;
3658 if (GET_CODE (value) == CONST_INT)
3660 if (HOST_BITS_PER_WIDE_INT >= (2 * BITS_PER_WORD))
3662 /* In this case the CONST_INT holds both target words.
3663 Extract the bits from it into two word-sized pieces.
3664 Sign extend each half to HOST_WIDE_INT. */
3665 unsigned HOST_WIDE_INT low, high;
3666 unsigned HOST_WIDE_INT mask, sign_bit, sign_extend;
3668 /* Set sign_bit to the most significant bit of a word. */
3669 sign_bit = 1;
3670 sign_bit <<= BITS_PER_WORD - 1;
3672 /* Set mask so that all bits of the word are set. We could
3673 have used 1 << BITS_PER_WORD instead of basing the
3674 calculation on sign_bit. However, on machines where
3675 HOST_BITS_PER_WIDE_INT == BITS_PER_WORD, it could cause a
3676 compiler warning, even though the code would never be
3677 executed. */
3678 mask = sign_bit << 1;
3679 mask--;
3681 /* Set sign_extend as any remaining bits. */
3682 sign_extend = ~mask;
3684 /* Pick the lower word and sign-extend it. */
3685 low = INTVAL (value);
3686 low &= mask;
3687 if (low & sign_bit)
3688 low |= sign_extend;
3690 /* Pick the higher word, shifted to the least significant
3691 bits, and sign-extend it. */
3692 high = INTVAL (value);
3693 high >>= BITS_PER_WORD - 1;
3694 high >>= 1;
3695 high &= mask;
3696 if (high & sign_bit)
3697 high |= sign_extend;
3699 /* Store the words in the target machine order. */
3700 if (WORDS_BIG_ENDIAN)
3702 *first = GEN_INT (high);
3703 *second = GEN_INT (low);
3705 else
3707 *first = GEN_INT (low);
3708 *second = GEN_INT (high);
3711 else
3713 /* The rule for using CONST_INT for a wider mode
3714 is that we regard the value as signed.
3715 So sign-extend it. */
3716 rtx high = (INTVAL (value) < 0 ? constm1_rtx : const0_rtx);
3717 if (WORDS_BIG_ENDIAN)
3719 *first = high;
3720 *second = value;
3722 else
3724 *first = value;
3725 *second = high;
3729 else if (GET_CODE (value) != CONST_DOUBLE)
3731 if (WORDS_BIG_ENDIAN)
3733 *first = const0_rtx;
3734 *second = value;
3736 else
3738 *first = value;
3739 *second = const0_rtx;
3742 else if (GET_MODE (value) == VOIDmode
3743 /* This is the old way we did CONST_DOUBLE integers. */
3744 || GET_MODE_CLASS (GET_MODE (value)) == MODE_INT)
3746 /* In an integer, the words are defined as most and least significant.
3747 So order them by the target's convention. */
3748 if (WORDS_BIG_ENDIAN)
3750 *first = GEN_INT (CONST_DOUBLE_HIGH (value));
3751 *second = GEN_INT (CONST_DOUBLE_LOW (value));
3753 else
3755 *first = GEN_INT (CONST_DOUBLE_LOW (value));
3756 *second = GEN_INT (CONST_DOUBLE_HIGH (value));
3759 else
3761 #ifdef REAL_ARITHMETIC
3762 REAL_VALUE_TYPE r;
3763 long l[2];
3764 REAL_VALUE_FROM_CONST_DOUBLE (r, value);
3766 /* Note, this converts the REAL_VALUE_TYPE to the target's
3767 format, splits up the floating point double and outputs
3768 exactly 32 bits of it into each of l[0] and l[1] --
3769 not necessarily BITS_PER_WORD bits. */
3770 REAL_VALUE_TO_TARGET_DOUBLE (r, l);
3772 /* If 32 bits is an entire word for the target, but not for the host,
3773 then sign-extend on the host so that the number will look the same
3774 way on the host that it would on the target. See for instance
3775 simplify_unary_operation. The #if is needed to avoid compiler
3776 warnings. */
3778 #if HOST_BITS_PER_LONG > 32
3779 if (BITS_PER_WORD < HOST_BITS_PER_LONG && BITS_PER_WORD == 32)
3781 if (l[0] & ((long) 1 << 31))
3782 l[0] |= ((long) (-1) << 32);
3783 if (l[1] & ((long) 1 << 31))
3784 l[1] |= ((long) (-1) << 32);
3786 #endif
3788 *first = GEN_INT ((HOST_WIDE_INT) l[0]);
3789 *second = GEN_INT ((HOST_WIDE_INT) l[1]);
3790 #else
3791 if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
3792 || HOST_BITS_PER_WIDE_INT != BITS_PER_WORD)
3793 && ! flag_pretend_float)
3794 abort ();
3796 if (
3797 #ifdef HOST_WORDS_BIG_ENDIAN
3798 WORDS_BIG_ENDIAN
3799 #else
3800 ! WORDS_BIG_ENDIAN
3801 #endif
3804 /* Host and target agree => no need to swap. */
3805 *first = GEN_INT (CONST_DOUBLE_LOW (value));
3806 *second = GEN_INT (CONST_DOUBLE_HIGH (value));
3808 else
3810 *second = GEN_INT (CONST_DOUBLE_LOW (value));
3811 *first = GEN_INT (CONST_DOUBLE_HIGH (value));
3813 #endif /* no REAL_ARITHMETIC */
3817 /* Return nonzero if this function has no function calls. */
3820 leaf_function_p ()
3822 rtx insn;
3823 rtx link;
3825 if (current_function_profile || profile_arc_flag)
3826 return 0;
3828 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3830 if (GET_CODE (insn) == CALL_INSN
3831 && ! SIBLING_CALL_P (insn))
3832 return 0;
3833 if (GET_CODE (insn) == INSN
3834 && GET_CODE (PATTERN (insn)) == SEQUENCE
3835 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == CALL_INSN
3836 && ! SIBLING_CALL_P (XVECEXP (PATTERN (insn), 0, 0)))
3837 return 0;
3839 for (link = current_function_epilogue_delay_list;
3840 link;
3841 link = XEXP (link, 1))
3843 insn = XEXP (link, 0);
3845 if (GET_CODE (insn) == CALL_INSN
3846 && ! SIBLING_CALL_P (insn))
3847 return 0;
3848 if (GET_CODE (insn) == INSN
3849 && GET_CODE (PATTERN (insn)) == SEQUENCE
3850 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == CALL_INSN
3851 && ! SIBLING_CALL_P (XVECEXP (PATTERN (insn), 0, 0)))
3852 return 0;
3855 return 1;
3858 /* Return 1 if branch is an forward branch.
3859 Uses insn_shuid array, so it works only in the final pass. May be used by
3860 output templates to customary add branch prediction hints.
3863 final_forward_branch_p (insn)
3864 rtx insn;
3866 int insn_id, label_id;
3867 if (!uid_shuid)
3868 abort ();
3869 insn_id = INSN_SHUID (insn);
3870 label_id = INSN_SHUID (JUMP_LABEL (insn));
3871 /* We've hit some insns that does not have id information available. */
3872 if (!insn_id || !label_id)
3873 abort ();
3874 return insn_id < label_id;
3877 /* On some machines, a function with no call insns
3878 can run faster if it doesn't create its own register window.
3879 When output, the leaf function should use only the "output"
3880 registers. Ordinarily, the function would be compiled to use
3881 the "input" registers to find its arguments; it is a candidate
3882 for leaf treatment if it uses only the "input" registers.
3883 Leaf function treatment means renumbering so the function
3884 uses the "output" registers instead. */
3886 #ifdef LEAF_REGISTERS
3888 /* Return 1 if this function uses only the registers that can be
3889 safely renumbered. */
3892 only_leaf_regs_used ()
3894 int i;
3895 char *permitted_reg_in_leaf_functions = LEAF_REGISTERS;
3897 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
3898 if ((regs_ever_live[i] || global_regs[i])
3899 && ! permitted_reg_in_leaf_functions[i])
3900 return 0;
3902 if (current_function_uses_pic_offset_table
3903 && pic_offset_table_rtx != 0
3904 && GET_CODE (pic_offset_table_rtx) == REG
3905 && ! permitted_reg_in_leaf_functions[REGNO (pic_offset_table_rtx)])
3906 return 0;
3908 return 1;
3911 /* Scan all instructions and renumber all registers into those
3912 available in leaf functions. */
3914 static void
3915 leaf_renumber_regs (first)
3916 rtx first;
3918 rtx insn;
3920 /* Renumber only the actual patterns.
3921 The reg-notes can contain frame pointer refs,
3922 and renumbering them could crash, and should not be needed. */
3923 for (insn = first; insn; insn = NEXT_INSN (insn))
3924 if (INSN_P (insn))
3925 leaf_renumber_regs_insn (PATTERN (insn));
3926 for (insn = current_function_epilogue_delay_list;
3927 insn;
3928 insn = XEXP (insn, 1))
3929 if (INSN_P (XEXP (insn, 0)))
3930 leaf_renumber_regs_insn (PATTERN (XEXP (insn, 0)));
3933 /* Scan IN_RTX and its subexpressions, and renumber all regs into those
3934 available in leaf functions. */
3936 void
3937 leaf_renumber_regs_insn (in_rtx)
3938 rtx in_rtx;
3940 int i, j;
3941 const char *format_ptr;
3943 if (in_rtx == 0)
3944 return;
3946 /* Renumber all input-registers into output-registers.
3947 renumbered_regs would be 1 for an output-register;
3948 they */
3950 if (GET_CODE (in_rtx) == REG)
3952 int newreg;
3954 /* Don't renumber the same reg twice. */
3955 if (in_rtx->used)
3956 return;
3958 newreg = REGNO (in_rtx);
3959 /* Don't try to renumber pseudo regs. It is possible for a pseudo reg
3960 to reach here as part of a REG_NOTE. */
3961 if (newreg >= FIRST_PSEUDO_REGISTER)
3963 in_rtx->used = 1;
3964 return;
3966 newreg = LEAF_REG_REMAP (newreg);
3967 if (newreg < 0)
3968 abort ();
3969 regs_ever_live[REGNO (in_rtx)] = 0;
3970 regs_ever_live[newreg] = 1;
3971 REGNO (in_rtx) = newreg;
3972 in_rtx->used = 1;
3975 if (INSN_P (in_rtx))
3977 /* Inside a SEQUENCE, we find insns.
3978 Renumber just the patterns of these insns,
3979 just as we do for the top-level insns. */
3980 leaf_renumber_regs_insn (PATTERN (in_rtx));
3981 return;
3984 format_ptr = GET_RTX_FORMAT (GET_CODE (in_rtx));
3986 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (in_rtx)); i++)
3987 switch (*format_ptr++)
3989 case 'e':
3990 leaf_renumber_regs_insn (XEXP (in_rtx, i));
3991 break;
3993 case 'E':
3994 if (NULL != XVEC (in_rtx, i))
3996 for (j = 0; j < XVECLEN (in_rtx, i); j++)
3997 leaf_renumber_regs_insn (XVECEXP (in_rtx, i, j));
3999 break;
4001 case 'S':
4002 case 's':
4003 case '0':
4004 case 'i':
4005 case 'w':
4006 case 'n':
4007 case 'u':
4008 break;
4010 default:
4011 abort ();
4014 #endif