2002-05-03 David S. Miller <davem@redhat.com>
[official-gcc.git] / gcc / final.c
bloba0adcbe70b4f4f4db1ceeac591f9bed2912f20b9
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 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 /* Number of unmatched NOTE_INSN_BLOCK_BEG notes we have seen. */
175 static int block_depth;
177 /* Nonzero if have enabled APP processing of our assembler output. */
179 static int app_on;
181 /* If we are outputting an insn sequence, this contains the sequence rtx.
182 Zero otherwise. */
184 rtx final_sequence;
186 #ifdef ASSEMBLER_DIALECT
188 /* Number of the assembler dialect to use, starting at 0. */
189 static int dialect_number;
190 #endif
192 /* Indexed by line number, nonzero if there is a note for that line. */
194 static char *line_note_exists;
196 #ifdef HAVE_conditional_execution
197 /* Nonnull if the insn currently being emitted was a COND_EXEC pattern. */
198 rtx current_insn_predicate;
199 #endif
201 #ifdef HAVE_ATTR_length
202 static int asm_insn_count PARAMS ((rtx));
203 #endif
204 static void profile_function PARAMS ((FILE *));
205 static void profile_after_prologue PARAMS ((FILE *));
206 static void notice_source_line PARAMS ((rtx));
207 static rtx walk_alter_subreg PARAMS ((rtx *));
208 static void output_asm_name PARAMS ((void));
209 static tree get_mem_expr_from_op PARAMS ((rtx, int *));
210 static void output_asm_operand_names PARAMS ((rtx *, int *, int));
211 static void output_operand PARAMS ((rtx, int));
212 #ifdef LEAF_REGISTERS
213 static void leaf_renumber_regs PARAMS ((rtx));
214 #endif
215 #ifdef HAVE_cc0
216 static int alter_cond PARAMS ((rtx));
217 #endif
218 #ifndef ADDR_VEC_ALIGN
219 static int final_addr_vec_align PARAMS ((rtx));
220 #endif
221 #ifdef HAVE_ATTR_length
222 static int align_fuzz PARAMS ((rtx, rtx, int, unsigned));
223 #endif
225 /* Initialize data in final at the beginning of a compilation. */
227 void
228 init_final (filename)
229 const char *filename ATTRIBUTE_UNUSED;
231 app_on = 0;
232 final_sequence = 0;
234 #ifdef ASSEMBLER_DIALECT
235 dialect_number = ASSEMBLER_DIALECT;
236 #endif
239 /* Called at end of source file,
240 to output the block-profiling table for this entire compilation. */
242 void
243 end_final (filename)
244 const char *filename;
246 if (profile_arc_flag)
248 char name[20];
249 int align = exact_log2 (BIGGEST_ALIGNMENT / BITS_PER_UNIT);
250 int size, rounded;
251 int long_bytes = LONG_TYPE_SIZE / BITS_PER_UNIT;
252 int gcov_type_bytes = GCOV_TYPE_SIZE / BITS_PER_UNIT;
253 int pointer_bytes = POINTER_SIZE / BITS_PER_UNIT;
254 unsigned int align2 = LONG_TYPE_SIZE;
256 size = gcov_type_bytes * count_instrumented_edges;
257 rounded = size;
259 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
260 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
261 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
263 /* ??? This _really_ ought to be done with a structure layout
264 and with assemble_constructor. If long_bytes != pointer_bytes
265 we'll be emitting unaligned data at some point. */
266 if (long_bytes != pointer_bytes)
267 abort ();
269 data_section ();
271 /* Output the main header, of 11 words:
272 0: 1 if this file is initialized, else 0.
273 1: address of file name (LPBX1).
274 2: address of table of counts (LPBX2).
275 3: number of counts in the table.
276 4: always 0, for compatibility with Sun.
278 The following are GNU extensions:
280 5: address of table of start addrs of basic blocks (LPBX3).
281 6: Number of bytes in this header.
282 7: address of table of function names (LPBX4).
283 8: address of table of line numbers (LPBX5) or 0.
284 9: address of table of file names (LPBX6) or 0.
285 10: space reserved for basic block profiling. */
287 ASM_OUTPUT_ALIGN (asm_out_file, align);
289 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 0);
291 /* Zero word. */
292 assemble_integer (const0_rtx, long_bytes, align2, 1);
294 /* Address of filename. */
295 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 1);
296 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name), pointer_bytes,
297 align2, 1);
299 /* Address of count table. */
300 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 2);
301 assemble_integer (gen_rtx_SYMBOL_REF (Pmode, name), pointer_bytes,
302 align2, 1);
304 /* Count of the # of instrumented arcs. */
305 assemble_integer (GEN_INT (count_instrumented_edges),
306 long_bytes, align2, 1);
308 /* Zero word (link field). */
309 assemble_integer (const0_rtx, pointer_bytes, align2, 1);
311 assemble_integer (const0_rtx, pointer_bytes, align2, 1);
313 /* Byte count for extended structure. */
314 assemble_integer (GEN_INT (11 * UNITS_PER_WORD), long_bytes, align2, 1);
316 /* Address of function name table. */
317 assemble_integer (const0_rtx, pointer_bytes, align2, 1);
319 /* Address of line number and filename tables if debugging. */
320 assemble_integer (const0_rtx, pointer_bytes, align2, 1);
321 assemble_integer (const0_rtx, pointer_bytes, align2, 1);
323 /* Space for extension ptr (link field). */
324 assemble_integer (const0_rtx, UNITS_PER_WORD, align2, 1);
326 /* Output the file name changing the suffix to .d for
327 Sun tcov compatibility. */
328 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 1);
330 char *cwd = getpwd ();
331 int len = strlen (filename) + strlen (cwd) + 1;
332 char *data_file = (char *) alloca (len + 4);
334 strcpy (data_file, cwd);
335 strcat (data_file, "/");
336 strcat (data_file, filename);
337 strip_off_ending (data_file, len);
338 strcat (data_file, ".da");
339 assemble_string (data_file, strlen (data_file) + 1);
342 /* Make space for the table of counts. */
343 if (size == 0)
345 /* Realign data section. */
346 ASM_OUTPUT_ALIGN (asm_out_file, align);
347 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LPBX", 2);
348 if (size != 0)
349 assemble_zeros (size);
351 else
353 ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 2);
354 #ifdef ASM_OUTPUT_SHARED_LOCAL
355 if (flag_shared_data)
356 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
357 else
358 #endif
359 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
360 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name,
361 size, BIGGEST_ALIGNMENT);
362 #else
363 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
364 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size,
365 BIGGEST_ALIGNMENT);
366 #else
367 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
368 #endif
369 #endif
374 /* Default target function prologue and epilogue assembler output.
376 If not overridden for epilogue code, then the function body itself
377 contains return instructions wherever needed. */
378 void
379 default_function_pro_epilogue (file, size)
380 FILE *file ATTRIBUTE_UNUSED;
381 HOST_WIDE_INT size ATTRIBUTE_UNUSED;
385 /* Default target hook that outputs nothing to a stream. */
386 void
387 no_asm_to_stream (file)
388 FILE *file ATTRIBUTE_UNUSED;
392 /* Enable APP processing of subsequent output.
393 Used before the output from an `asm' statement. */
395 void
396 app_enable ()
398 if (! app_on)
400 fputs (ASM_APP_ON, asm_out_file);
401 app_on = 1;
405 /* Disable APP processing of subsequent output.
406 Called from varasm.c before most kinds of output. */
408 void
409 app_disable ()
411 if (app_on)
413 fputs (ASM_APP_OFF, asm_out_file);
414 app_on = 0;
418 /* Return the number of slots filled in the current
419 delayed branch sequence (we don't count the insn needing the
420 delay slot). Zero if not in a delayed branch sequence. */
422 #ifdef DELAY_SLOTS
424 dbr_sequence_length ()
426 if (final_sequence != 0)
427 return XVECLEN (final_sequence, 0) - 1;
428 else
429 return 0;
431 #endif
433 /* The next two pages contain routines used to compute the length of an insn
434 and to shorten branches. */
436 /* Arrays for insn lengths, and addresses. The latter is referenced by
437 `insn_current_length'. */
439 static int *insn_lengths;
441 #ifdef HAVE_ATTR_length
442 varray_type insn_addresses_;
443 #endif
445 /* Max uid for which the above arrays are valid. */
446 static int insn_lengths_max_uid;
448 /* Address of insn being processed. Used by `insn_current_length'. */
449 int insn_current_address;
451 /* Address of insn being processed in previous iteration. */
452 int insn_last_address;
454 /* known invariant alignment of insn being processed. */
455 int insn_current_align;
457 /* After shorten_branches, for any insn, uid_align[INSN_UID (insn)]
458 gives the next following alignment insn that increases the known
459 alignment, or NULL_RTX if there is no such insn.
460 For any alignment obtained this way, we can again index uid_align with
461 its uid to obtain the next following align that in turn increases the
462 alignment, till we reach NULL_RTX; the sequence obtained this way
463 for each insn we'll call the alignment chain of this insn in the following
464 comments. */
466 struct label_alignment
468 short alignment;
469 short max_skip;
472 static rtx *uid_align;
473 static int *uid_shuid;
474 static struct label_alignment *label_align;
476 /* Indicate that branch shortening hasn't yet been done. */
478 void
479 init_insn_lengths ()
481 if (uid_shuid)
483 free (uid_shuid);
484 uid_shuid = 0;
486 if (insn_lengths)
488 free (insn_lengths);
489 insn_lengths = 0;
490 insn_lengths_max_uid = 0;
492 #ifdef HAVE_ATTR_length
493 INSN_ADDRESSES_FREE ();
494 #endif
495 if (uid_align)
497 free (uid_align);
498 uid_align = 0;
502 /* Obtain the current length of an insn. If branch shortening has been done,
503 get its actual length. Otherwise, get its maximum length. */
506 get_attr_length (insn)
507 rtx insn ATTRIBUTE_UNUSED;
509 #ifdef HAVE_ATTR_length
510 rtx body;
511 int i;
512 int length = 0;
514 if (insn_lengths_max_uid > INSN_UID (insn))
515 return insn_lengths[INSN_UID (insn)];
516 else
517 switch (GET_CODE (insn))
519 case NOTE:
520 case BARRIER:
521 case CODE_LABEL:
522 return 0;
524 case CALL_INSN:
525 length = insn_default_length (insn);
526 break;
528 case JUMP_INSN:
529 body = PATTERN (insn);
530 if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
532 /* Alignment is machine-dependent and should be handled by
533 ADDR_VEC_ALIGN. */
535 else
536 length = insn_default_length (insn);
537 break;
539 case INSN:
540 body = PATTERN (insn);
541 if (GET_CODE (body) == USE || GET_CODE (body) == CLOBBER)
542 return 0;
544 else if (GET_CODE (body) == ASM_INPUT || asm_noperands (body) >= 0)
545 length = asm_insn_count (body) * insn_default_length (insn);
546 else if (GET_CODE (body) == SEQUENCE)
547 for (i = 0; i < XVECLEN (body, 0); i++)
548 length += get_attr_length (XVECEXP (body, 0, i));
549 else
550 length = insn_default_length (insn);
551 break;
553 default:
554 break;
557 #ifdef ADJUST_INSN_LENGTH
558 ADJUST_INSN_LENGTH (insn, length);
559 #endif
560 return length;
561 #else /* not HAVE_ATTR_length */
562 return 0;
563 #endif /* not HAVE_ATTR_length */
566 /* Code to handle alignment inside shorten_branches. */
568 /* Here is an explanation how the algorithm in align_fuzz can give
569 proper results:
571 Call a sequence of instructions beginning with alignment point X
572 and continuing until the next alignment point `block X'. When `X'
573 is used in an expression, it means the alignment value of the
574 alignment point.
576 Call the distance between the start of the first insn of block X, and
577 the end of the last insn of block X `IX', for the `inner size of X'.
578 This is clearly the sum of the instruction lengths.
580 Likewise with the next alignment-delimited block following X, which we
581 shall call block Y.
583 Call the distance between the start of the first insn of block X, and
584 the start of the first insn of block Y `OX', for the `outer size of X'.
586 The estimated padding is then OX - IX.
588 OX can be safely estimated as
590 if (X >= Y)
591 OX = round_up(IX, Y)
592 else
593 OX = round_up(IX, X) + Y - X
595 Clearly est(IX) >= real(IX), because that only depends on the
596 instruction lengths, and those being overestimated is a given.
598 Clearly round_up(foo, Z) >= round_up(bar, Z) if foo >= bar, so
599 we needn't worry about that when thinking about OX.
601 When X >= Y, the alignment provided by Y adds no uncertainty factor
602 for branch ranges starting before X, so we can just round what we have.
603 But when X < Y, we don't know anything about the, so to speak,
604 `middle bits', so we have to assume the worst when aligning up from an
605 address mod X to one mod Y, which is Y - X. */
607 #ifndef LABEL_ALIGN
608 #define LABEL_ALIGN(LABEL) align_labels_log
609 #endif
611 #ifndef LABEL_ALIGN_MAX_SKIP
612 #define LABEL_ALIGN_MAX_SKIP align_labels_max_skip
613 #endif
615 #ifndef LOOP_ALIGN
616 #define LOOP_ALIGN(LABEL) align_loops_log
617 #endif
619 #ifndef LOOP_ALIGN_MAX_SKIP
620 #define LOOP_ALIGN_MAX_SKIP align_loops_max_skip
621 #endif
623 #ifndef LABEL_ALIGN_AFTER_BARRIER
624 #define LABEL_ALIGN_AFTER_BARRIER(LABEL) 0
625 #endif
627 #ifndef LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP
628 #define LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP 0
629 #endif
631 #ifndef JUMP_ALIGN
632 #define JUMP_ALIGN(LABEL) align_jumps_log
633 #endif
635 #ifndef JUMP_ALIGN_MAX_SKIP
636 #define JUMP_ALIGN_MAX_SKIP align_jumps_max_skip
637 #endif
639 #ifndef ADDR_VEC_ALIGN
640 static int
641 final_addr_vec_align (addr_vec)
642 rtx addr_vec;
644 int align = GET_MODE_SIZE (GET_MODE (PATTERN (addr_vec)));
646 if (align > BIGGEST_ALIGNMENT / BITS_PER_UNIT)
647 align = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
648 return exact_log2 (align);
652 #define ADDR_VEC_ALIGN(ADDR_VEC) final_addr_vec_align (ADDR_VEC)
653 #endif
655 #ifndef INSN_LENGTH_ALIGNMENT
656 #define INSN_LENGTH_ALIGNMENT(INSN) length_unit_log
657 #endif
659 #define INSN_SHUID(INSN) (uid_shuid[INSN_UID (INSN)])
661 static int min_labelno, max_labelno;
663 #define LABEL_TO_ALIGNMENT(LABEL) \
664 (label_align[CODE_LABEL_NUMBER (LABEL) - min_labelno].alignment)
666 #define LABEL_TO_MAX_SKIP(LABEL) \
667 (label_align[CODE_LABEL_NUMBER (LABEL) - min_labelno].max_skip)
669 /* For the benefit of port specific code do this also as a function. */
672 label_to_alignment (label)
673 rtx label;
675 return LABEL_TO_ALIGNMENT (label);
678 #ifdef HAVE_ATTR_length
679 /* The differences in addresses
680 between a branch and its target might grow or shrink depending on
681 the alignment the start insn of the range (the branch for a forward
682 branch or the label for a backward branch) starts out on; if these
683 differences are used naively, they can even oscillate infinitely.
684 We therefore want to compute a 'worst case' address difference that
685 is independent of the alignment the start insn of the range end
686 up on, and that is at least as large as the actual difference.
687 The function align_fuzz calculates the amount we have to add to the
688 naively computed difference, by traversing the part of the alignment
689 chain of the start insn of the range that is in front of the end insn
690 of the range, and considering for each alignment the maximum amount
691 that it might contribute to a size increase.
693 For casesi tables, we also want to know worst case minimum amounts of
694 address difference, in case a machine description wants to introduce
695 some common offset that is added to all offsets in a table.
696 For this purpose, align_fuzz with a growth argument of 0 computes the
697 appropriate adjustment. */
699 /* Compute the maximum delta by which the difference of the addresses of
700 START and END might grow / shrink due to a different address for start
701 which changes the size of alignment insns between START and END.
702 KNOWN_ALIGN_LOG is the alignment known for START.
703 GROWTH should be ~0 if the objective is to compute potential code size
704 increase, and 0 if the objective is to compute potential shrink.
705 The return value is undefined for any other value of GROWTH. */
707 static int
708 align_fuzz (start, end, known_align_log, growth)
709 rtx start, end;
710 int known_align_log;
711 unsigned growth;
713 int uid = INSN_UID (start);
714 rtx align_label;
715 int known_align = 1 << known_align_log;
716 int end_shuid = INSN_SHUID (end);
717 int fuzz = 0;
719 for (align_label = uid_align[uid]; align_label; align_label = uid_align[uid])
721 int align_addr, new_align;
723 uid = INSN_UID (align_label);
724 align_addr = INSN_ADDRESSES (uid) - insn_lengths[uid];
725 if (uid_shuid[uid] > end_shuid)
726 break;
727 known_align_log = LABEL_TO_ALIGNMENT (align_label);
728 new_align = 1 << known_align_log;
729 if (new_align < known_align)
730 continue;
731 fuzz += (-align_addr ^ growth) & (new_align - known_align);
732 known_align = new_align;
734 return fuzz;
737 /* Compute a worst-case reference address of a branch so that it
738 can be safely used in the presence of aligned labels. Since the
739 size of the branch itself is unknown, the size of the branch is
740 not included in the range. I.e. for a forward branch, the reference
741 address is the end address of the branch as known from the previous
742 branch shortening pass, minus a value to account for possible size
743 increase due to alignment. For a backward branch, it is the start
744 address of the branch as known from the current pass, plus a value
745 to account for possible size increase due to alignment.
746 NB.: Therefore, the maximum offset allowed for backward branches needs
747 to exclude the branch size. */
750 insn_current_reference_address (branch)
751 rtx branch;
753 rtx dest, seq;
754 int seq_uid;
756 if (! INSN_ADDRESSES_SET_P ())
757 return 0;
759 seq = NEXT_INSN (PREV_INSN (branch));
760 seq_uid = INSN_UID (seq);
761 if (GET_CODE (branch) != JUMP_INSN)
762 /* This can happen for example on the PA; the objective is to know the
763 offset to address something in front of the start of the function.
764 Thus, we can treat it like a backward branch.
765 We assume here that FUNCTION_BOUNDARY / BITS_PER_UNIT is larger than
766 any alignment we'd encounter, so we skip the call to align_fuzz. */
767 return insn_current_address;
768 dest = JUMP_LABEL (branch);
770 /* BRANCH has no proper alignment chain set, so use SEQ.
771 BRANCH also has no INSN_SHUID. */
772 if (INSN_SHUID (seq) < INSN_SHUID (dest))
774 /* Forward branch. */
775 return (insn_last_address + insn_lengths[seq_uid]
776 - align_fuzz (seq, dest, length_unit_log, ~0));
778 else
780 /* Backward branch. */
781 return (insn_current_address
782 + align_fuzz (dest, seq, length_unit_log, ~0));
785 #endif /* HAVE_ATTR_length */
787 void
788 compute_alignments ()
790 int i;
791 int log, max_skip, max_log;
793 if (label_align)
795 free (label_align);
796 label_align = 0;
799 max_labelno = max_label_num ();
800 min_labelno = get_first_label_num ();
801 label_align = (struct label_alignment *)
802 xcalloc (max_labelno - min_labelno + 1, sizeof (struct label_alignment));
804 /* If not optimizing or optimizing for size, don't assign any alignments. */
805 if (! optimize || optimize_size)
806 return;
808 for (i = 0; i < n_basic_blocks; i++)
810 basic_block bb = BASIC_BLOCK (i);
811 rtx label = bb->head;
812 int fallthru_frequency = 0, branch_frequency = 0, has_fallthru = 0;
813 edge e;
815 if (GET_CODE (label) != CODE_LABEL)
816 continue;
817 max_log = LABEL_ALIGN (label);
818 max_skip = LABEL_ALIGN_MAX_SKIP;
820 for (e = bb->pred; e; e = e->pred_next)
822 if (e->flags & EDGE_FALLTHRU)
823 has_fallthru = 1, fallthru_frequency += EDGE_FREQUENCY (e);
824 else
825 branch_frequency += EDGE_FREQUENCY (e);
828 /* There are two purposes to align block with no fallthru incoming edge:
829 1) to avoid fetch stalls when branch destination is near cache boundary
830 2) to improve cache efficiency in case the previous block is not executed
831 (so it does not need to be in the cache).
833 We to catch first case, we align frequently executed blocks.
834 To catch the second, we align blocks that are executed more frequently
835 than the predecessor and the predecessor is likely to not be executed
836 when function is called. */
838 if (!has_fallthru
839 && (branch_frequency > BB_FREQ_MAX / 10
840 || (bb->frequency > BASIC_BLOCK (i - 1)->frequency * 10
841 && (BASIC_BLOCK (i - 1)->frequency
842 <= ENTRY_BLOCK_PTR->frequency / 2))))
844 log = JUMP_ALIGN (label);
845 if (max_log < log)
847 max_log = log;
848 max_skip = JUMP_ALIGN_MAX_SKIP;
851 /* In case block is frequent and reached mostly by non-fallthru edge,
852 align it. It is most likely an first block of loop. */
853 if (has_fallthru
854 && branch_frequency + fallthru_frequency > BB_FREQ_MAX / 10
855 && branch_frequency > fallthru_frequency * 5)
857 log = LOOP_ALIGN (label);
858 if (max_log < log)
860 max_log = log;
861 max_skip = LOOP_ALIGN_MAX_SKIP;
864 LABEL_TO_ALIGNMENT (label) = max_log;
865 LABEL_TO_MAX_SKIP (label) = max_skip;
869 /* Make a pass over all insns and compute their actual lengths by shortening
870 any branches of variable length if possible. */
872 /* Give a default value for the lowest address in a function. */
874 #ifndef FIRST_INSN_ADDRESS
875 #define FIRST_INSN_ADDRESS 0
876 #endif
878 /* shorten_branches might be called multiple times: for example, the SH
879 port splits out-of-range conditional branches in MACHINE_DEPENDENT_REORG.
880 In order to do this, it needs proper length information, which it obtains
881 by calling shorten_branches. This cannot be collapsed with
882 shorten_branches itself into a single pass unless we also want to integrate
883 reorg.c, since the branch splitting exposes new instructions with delay
884 slots. */
886 void
887 shorten_branches (first)
888 rtx first ATTRIBUTE_UNUSED;
890 rtx insn;
891 int max_uid;
892 int i;
893 int max_log;
894 int max_skip;
895 #ifdef HAVE_ATTR_length
896 #define MAX_CODE_ALIGN 16
897 rtx seq;
898 int something_changed = 1;
899 char *varying_length;
900 rtx body;
901 int uid;
902 rtx align_tab[MAX_CODE_ALIGN];
904 #endif
906 /* Compute maximum UID and allocate label_align / uid_shuid. */
907 max_uid = get_max_uid ();
909 uid_shuid = (int *) xmalloc (max_uid * sizeof *uid_shuid);
911 if (max_labelno != max_label_num ())
913 int old = max_labelno;
914 int n_labels;
915 int n_old_labels;
917 max_labelno = max_label_num ();
919 n_labels = max_labelno - min_labelno + 1;
920 n_old_labels = old - min_labelno + 1;
922 label_align = (struct label_alignment *) xrealloc
923 (label_align, n_labels * sizeof (struct label_alignment));
925 /* Range of labels grows monotonically in the function. Abort here
926 means that the initialization of array got lost. */
927 if (n_old_labels > n_labels)
928 abort ();
930 memset (label_align + n_old_labels, 0,
931 (n_labels - n_old_labels) * sizeof (struct label_alignment));
934 /* Initialize label_align and set up uid_shuid to be strictly
935 monotonically rising with insn order. */
936 /* We use max_log here to keep track of the maximum alignment we want to
937 impose on the next CODE_LABEL (or the current one if we are processing
938 the CODE_LABEL itself). */
940 max_log = 0;
941 max_skip = 0;
943 for (insn = get_insns (), i = 1; insn; insn = NEXT_INSN (insn))
945 int log;
947 INSN_SHUID (insn) = i++;
948 if (INSN_P (insn))
950 /* reorg might make the first insn of a loop being run once only,
951 and delete the label in front of it. Then we want to apply
952 the loop alignment to the new label created by reorg, which
953 is separated by the former loop start insn from the
954 NOTE_INSN_LOOP_BEG. */
956 else if (GET_CODE (insn) == CODE_LABEL)
958 rtx next;
960 /* Merge in alignments computed by compute_alignments. */
961 log = LABEL_TO_ALIGNMENT (insn);
962 if (max_log < log)
964 max_log = log;
965 max_skip = LABEL_TO_MAX_SKIP (insn);
968 log = LABEL_ALIGN (insn);
969 if (max_log < log)
971 max_log = log;
972 max_skip = LABEL_ALIGN_MAX_SKIP;
974 next = NEXT_INSN (insn);
975 /* ADDR_VECs only take room if read-only data goes into the text
976 section. */
977 if (JUMP_TABLES_IN_TEXT_SECTION
978 #if !defined(READONLY_DATA_SECTION)
979 || 1
980 #endif
982 if (next && GET_CODE (next) == JUMP_INSN)
984 rtx nextbody = PATTERN (next);
985 if (GET_CODE (nextbody) == ADDR_VEC
986 || GET_CODE (nextbody) == ADDR_DIFF_VEC)
988 log = ADDR_VEC_ALIGN (next);
989 if (max_log < log)
991 max_log = log;
992 max_skip = LABEL_ALIGN_MAX_SKIP;
996 LABEL_TO_ALIGNMENT (insn) = max_log;
997 LABEL_TO_MAX_SKIP (insn) = max_skip;
998 max_log = 0;
999 max_skip = 0;
1001 else if (GET_CODE (insn) == BARRIER)
1003 rtx label;
1005 for (label = insn; label && ! INSN_P (label);
1006 label = NEXT_INSN (label))
1007 if (GET_CODE (label) == CODE_LABEL)
1009 log = LABEL_ALIGN_AFTER_BARRIER (insn);
1010 if (max_log < log)
1012 max_log = log;
1013 max_skip = LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP;
1015 break;
1019 #ifdef HAVE_ATTR_length
1021 /* Allocate the rest of the arrays. */
1022 insn_lengths = (int *) xmalloc (max_uid * sizeof (*insn_lengths));
1023 insn_lengths_max_uid = max_uid;
1024 /* Syntax errors can lead to labels being outside of the main insn stream.
1025 Initialize insn_addresses, so that we get reproducible results. */
1026 INSN_ADDRESSES_ALLOC (max_uid);
1028 varying_length = (char *) xcalloc (max_uid, sizeof (char));
1030 /* Initialize uid_align. We scan instructions
1031 from end to start, and keep in align_tab[n] the last seen insn
1032 that does an alignment of at least n+1, i.e. the successor
1033 in the alignment chain for an insn that does / has a known
1034 alignment of n. */
1035 uid_align = (rtx *) xcalloc (max_uid, sizeof *uid_align);
1037 for (i = MAX_CODE_ALIGN; --i >= 0;)
1038 align_tab[i] = NULL_RTX;
1039 seq = get_last_insn ();
1040 for (; seq; seq = PREV_INSN (seq))
1042 int uid = INSN_UID (seq);
1043 int log;
1044 log = (GET_CODE (seq) == CODE_LABEL ? LABEL_TO_ALIGNMENT (seq) : 0);
1045 uid_align[uid] = align_tab[0];
1046 if (log)
1048 /* Found an alignment label. */
1049 uid_align[uid] = align_tab[log];
1050 for (i = log - 1; i >= 0; i--)
1051 align_tab[i] = seq;
1054 #ifdef CASE_VECTOR_SHORTEN_MODE
1055 if (optimize)
1057 /* Look for ADDR_DIFF_VECs, and initialize their minimum and maximum
1058 label fields. */
1060 int min_shuid = INSN_SHUID (get_insns ()) - 1;
1061 int max_shuid = INSN_SHUID (get_last_insn ()) + 1;
1062 int rel;
1064 for (insn = first; insn != 0; insn = NEXT_INSN (insn))
1066 rtx min_lab = NULL_RTX, max_lab = NULL_RTX, pat;
1067 int len, i, min, max, insn_shuid;
1068 int min_align;
1069 addr_diff_vec_flags flags;
1071 if (GET_CODE (insn) != JUMP_INSN
1072 || GET_CODE (PATTERN (insn)) != ADDR_DIFF_VEC)
1073 continue;
1074 pat = PATTERN (insn);
1075 len = XVECLEN (pat, 1);
1076 if (len <= 0)
1077 abort ();
1078 min_align = MAX_CODE_ALIGN;
1079 for (min = max_shuid, max = min_shuid, i = len - 1; i >= 0; i--)
1081 rtx lab = XEXP (XVECEXP (pat, 1, i), 0);
1082 int shuid = INSN_SHUID (lab);
1083 if (shuid < min)
1085 min = shuid;
1086 min_lab = lab;
1088 if (shuid > max)
1090 max = shuid;
1091 max_lab = lab;
1093 if (min_align > LABEL_TO_ALIGNMENT (lab))
1094 min_align = LABEL_TO_ALIGNMENT (lab);
1096 XEXP (pat, 2) = gen_rtx_LABEL_REF (VOIDmode, min_lab);
1097 XEXP (pat, 3) = gen_rtx_LABEL_REF (VOIDmode, max_lab);
1098 insn_shuid = INSN_SHUID (insn);
1099 rel = INSN_SHUID (XEXP (XEXP (pat, 0), 0));
1100 flags.min_align = min_align;
1101 flags.base_after_vec = rel > insn_shuid;
1102 flags.min_after_vec = min > insn_shuid;
1103 flags.max_after_vec = max > insn_shuid;
1104 flags.min_after_base = min > rel;
1105 flags.max_after_base = max > rel;
1106 ADDR_DIFF_VEC_FLAGS (pat) = flags;
1109 #endif /* CASE_VECTOR_SHORTEN_MODE */
1111 /* Compute initial lengths, addresses, and varying flags for each insn. */
1112 for (insn_current_address = FIRST_INSN_ADDRESS, insn = first;
1113 insn != 0;
1114 insn_current_address += insn_lengths[uid], insn = NEXT_INSN (insn))
1116 uid = INSN_UID (insn);
1118 insn_lengths[uid] = 0;
1120 if (GET_CODE (insn) == CODE_LABEL)
1122 int log = LABEL_TO_ALIGNMENT (insn);
1123 if (log)
1125 int align = 1 << log;
1126 int new_address = (insn_current_address + align - 1) & -align;
1127 insn_lengths[uid] = new_address - insn_current_address;
1131 INSN_ADDRESSES (uid) = insn_current_address;
1133 if (GET_CODE (insn) == NOTE || GET_CODE (insn) == BARRIER
1134 || GET_CODE (insn) == CODE_LABEL)
1135 continue;
1136 if (INSN_DELETED_P (insn))
1137 continue;
1139 body = PATTERN (insn);
1140 if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
1142 /* This only takes room if read-only data goes into the text
1143 section. */
1144 if (JUMP_TABLES_IN_TEXT_SECTION
1145 #if !defined(READONLY_DATA_SECTION)
1146 || 1
1147 #endif
1149 insn_lengths[uid] = (XVECLEN (body,
1150 GET_CODE (body) == ADDR_DIFF_VEC)
1151 * GET_MODE_SIZE (GET_MODE (body)));
1152 /* Alignment is handled by ADDR_VEC_ALIGN. */
1154 else if (GET_CODE (body) == ASM_INPUT || asm_noperands (body) >= 0)
1155 insn_lengths[uid] = asm_insn_count (body) * insn_default_length (insn);
1156 else if (GET_CODE (body) == SEQUENCE)
1158 int i;
1159 int const_delay_slots;
1160 #ifdef DELAY_SLOTS
1161 const_delay_slots = const_num_delay_slots (XVECEXP (body, 0, 0));
1162 #else
1163 const_delay_slots = 0;
1164 #endif
1165 /* Inside a delay slot sequence, we do not do any branch shortening
1166 if the shortening could change the number of delay slots
1167 of the branch. */
1168 for (i = 0; i < XVECLEN (body, 0); i++)
1170 rtx inner_insn = XVECEXP (body, 0, i);
1171 int inner_uid = INSN_UID (inner_insn);
1172 int inner_length;
1174 if (GET_CODE (body) == ASM_INPUT
1175 || asm_noperands (PATTERN (XVECEXP (body, 0, i))) >= 0)
1176 inner_length = (asm_insn_count (PATTERN (inner_insn))
1177 * insn_default_length (inner_insn));
1178 else
1179 inner_length = insn_default_length (inner_insn);
1181 insn_lengths[inner_uid] = inner_length;
1182 if (const_delay_slots)
1184 if ((varying_length[inner_uid]
1185 = insn_variable_length_p (inner_insn)) != 0)
1186 varying_length[uid] = 1;
1187 INSN_ADDRESSES (inner_uid) = (insn_current_address
1188 + insn_lengths[uid]);
1190 else
1191 varying_length[inner_uid] = 0;
1192 insn_lengths[uid] += inner_length;
1195 else if (GET_CODE (body) != USE && GET_CODE (body) != CLOBBER)
1197 insn_lengths[uid] = insn_default_length (insn);
1198 varying_length[uid] = insn_variable_length_p (insn);
1201 /* If needed, do any adjustment. */
1202 #ifdef ADJUST_INSN_LENGTH
1203 ADJUST_INSN_LENGTH (insn, insn_lengths[uid]);
1204 if (insn_lengths[uid] < 0)
1205 fatal_insn ("negative insn length", insn);
1206 #endif
1209 /* Now loop over all the insns finding varying length insns. For each,
1210 get the current insn length. If it has changed, reflect the change.
1211 When nothing changes for a full pass, we are done. */
1213 while (something_changed)
1215 something_changed = 0;
1216 insn_current_align = MAX_CODE_ALIGN - 1;
1217 for (insn_current_address = FIRST_INSN_ADDRESS, insn = first;
1218 insn != 0;
1219 insn = NEXT_INSN (insn))
1221 int new_length;
1222 #ifdef ADJUST_INSN_LENGTH
1223 int tmp_length;
1224 #endif
1225 int length_align;
1227 uid = INSN_UID (insn);
1229 if (GET_CODE (insn) == CODE_LABEL)
1231 int log = LABEL_TO_ALIGNMENT (insn);
1232 if (log > insn_current_align)
1234 int align = 1 << log;
1235 int new_address= (insn_current_address + align - 1) & -align;
1236 insn_lengths[uid] = new_address - insn_current_address;
1237 insn_current_align = log;
1238 insn_current_address = new_address;
1240 else
1241 insn_lengths[uid] = 0;
1242 INSN_ADDRESSES (uid) = insn_current_address;
1243 continue;
1246 length_align = INSN_LENGTH_ALIGNMENT (insn);
1247 if (length_align < insn_current_align)
1248 insn_current_align = length_align;
1250 insn_last_address = INSN_ADDRESSES (uid);
1251 INSN_ADDRESSES (uid) = insn_current_address;
1253 #ifdef CASE_VECTOR_SHORTEN_MODE
1254 if (optimize && GET_CODE (insn) == JUMP_INSN
1255 && GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)
1257 rtx body = PATTERN (insn);
1258 int old_length = insn_lengths[uid];
1259 rtx rel_lab = XEXP (XEXP (body, 0), 0);
1260 rtx min_lab = XEXP (XEXP (body, 2), 0);
1261 rtx max_lab = XEXP (XEXP (body, 3), 0);
1262 int rel_addr = INSN_ADDRESSES (INSN_UID (rel_lab));
1263 int min_addr = INSN_ADDRESSES (INSN_UID (min_lab));
1264 int max_addr = INSN_ADDRESSES (INSN_UID (max_lab));
1265 rtx prev;
1266 int rel_align = 0;
1267 addr_diff_vec_flags flags;
1269 /* Avoid automatic aggregate initialization. */
1270 flags = ADDR_DIFF_VEC_FLAGS (body);
1272 /* Try to find a known alignment for rel_lab. */
1273 for (prev = rel_lab;
1274 prev
1275 && ! insn_lengths[INSN_UID (prev)]
1276 && ! (varying_length[INSN_UID (prev)] & 1);
1277 prev = PREV_INSN (prev))
1278 if (varying_length[INSN_UID (prev)] & 2)
1280 rel_align = LABEL_TO_ALIGNMENT (prev);
1281 break;
1284 /* See the comment on addr_diff_vec_flags in rtl.h for the
1285 meaning of the flags values. base: REL_LAB vec: INSN */
1286 /* Anything after INSN has still addresses from the last
1287 pass; adjust these so that they reflect our current
1288 estimate for this pass. */
1289 if (flags.base_after_vec)
1290 rel_addr += insn_current_address - insn_last_address;
1291 if (flags.min_after_vec)
1292 min_addr += insn_current_address - insn_last_address;
1293 if (flags.max_after_vec)
1294 max_addr += insn_current_address - insn_last_address;
1295 /* We want to know the worst case, i.e. lowest possible value
1296 for the offset of MIN_LAB. If MIN_LAB is after REL_LAB,
1297 its offset is positive, and we have to be wary of code shrink;
1298 otherwise, it is negative, and we have to be vary of code
1299 size increase. */
1300 if (flags.min_after_base)
1302 /* If INSN is between REL_LAB and MIN_LAB, the size
1303 changes we are about to make can change the alignment
1304 within the observed offset, therefore we have to break
1305 it up into two parts that are independent. */
1306 if (! flags.base_after_vec && flags.min_after_vec)
1308 min_addr -= align_fuzz (rel_lab, insn, rel_align, 0);
1309 min_addr -= align_fuzz (insn, min_lab, 0, 0);
1311 else
1312 min_addr -= align_fuzz (rel_lab, min_lab, rel_align, 0);
1314 else
1316 if (flags.base_after_vec && ! flags.min_after_vec)
1318 min_addr -= align_fuzz (min_lab, insn, 0, ~0);
1319 min_addr -= align_fuzz (insn, rel_lab, 0, ~0);
1321 else
1322 min_addr -= align_fuzz (min_lab, rel_lab, 0, ~0);
1324 /* Likewise, determine the highest lowest possible value
1325 for the offset of MAX_LAB. */
1326 if (flags.max_after_base)
1328 if (! flags.base_after_vec && flags.max_after_vec)
1330 max_addr += align_fuzz (rel_lab, insn, rel_align, ~0);
1331 max_addr += align_fuzz (insn, max_lab, 0, ~0);
1333 else
1334 max_addr += align_fuzz (rel_lab, max_lab, rel_align, ~0);
1336 else
1338 if (flags.base_after_vec && ! flags.max_after_vec)
1340 max_addr += align_fuzz (max_lab, insn, 0, 0);
1341 max_addr += align_fuzz (insn, rel_lab, 0, 0);
1343 else
1344 max_addr += align_fuzz (max_lab, rel_lab, 0, 0);
1346 PUT_MODE (body, CASE_VECTOR_SHORTEN_MODE (min_addr - rel_addr,
1347 max_addr - rel_addr,
1348 body));
1349 if (JUMP_TABLES_IN_TEXT_SECTION
1350 #if !defined(READONLY_DATA_SECTION)
1351 || 1
1352 #endif
1355 insn_lengths[uid]
1356 = (XVECLEN (body, 1) * GET_MODE_SIZE (GET_MODE (body)));
1357 insn_current_address += insn_lengths[uid];
1358 if (insn_lengths[uid] != old_length)
1359 something_changed = 1;
1362 continue;
1364 #endif /* CASE_VECTOR_SHORTEN_MODE */
1366 if (! (varying_length[uid]))
1368 if (GET_CODE (insn) == INSN
1369 && GET_CODE (PATTERN (insn)) == SEQUENCE)
1371 int i;
1373 body = PATTERN (insn);
1374 for (i = 0; i < XVECLEN (body, 0); i++)
1376 rtx inner_insn = XVECEXP (body, 0, i);
1377 int inner_uid = INSN_UID (inner_insn);
1379 INSN_ADDRESSES (inner_uid) = insn_current_address;
1381 insn_current_address += insn_lengths[inner_uid];
1384 else
1385 insn_current_address += insn_lengths[uid];
1387 continue;
1390 if (GET_CODE (insn) == INSN && GET_CODE (PATTERN (insn)) == SEQUENCE)
1392 int i;
1394 body = PATTERN (insn);
1395 new_length = 0;
1396 for (i = 0; i < XVECLEN (body, 0); i++)
1398 rtx inner_insn = XVECEXP (body, 0, i);
1399 int inner_uid = INSN_UID (inner_insn);
1400 int inner_length;
1402 INSN_ADDRESSES (inner_uid) = insn_current_address;
1404 /* insn_current_length returns 0 for insns with a
1405 non-varying length. */
1406 if (! varying_length[inner_uid])
1407 inner_length = insn_lengths[inner_uid];
1408 else
1409 inner_length = insn_current_length (inner_insn);
1411 if (inner_length != insn_lengths[inner_uid])
1413 insn_lengths[inner_uid] = inner_length;
1414 something_changed = 1;
1416 insn_current_address += insn_lengths[inner_uid];
1417 new_length += inner_length;
1420 else
1422 new_length = insn_current_length (insn);
1423 insn_current_address += new_length;
1426 #ifdef ADJUST_INSN_LENGTH
1427 /* If needed, do any adjustment. */
1428 tmp_length = new_length;
1429 ADJUST_INSN_LENGTH (insn, new_length);
1430 insn_current_address += (new_length - tmp_length);
1431 #endif
1433 if (new_length != insn_lengths[uid])
1435 insn_lengths[uid] = new_length;
1436 something_changed = 1;
1439 /* For a non-optimizing compile, do only a single pass. */
1440 if (!optimize)
1441 break;
1444 free (varying_length);
1446 #endif /* HAVE_ATTR_length */
1449 #ifdef HAVE_ATTR_length
1450 /* Given the body of an INSN known to be generated by an ASM statement, return
1451 the number of machine instructions likely to be generated for this insn.
1452 This is used to compute its length. */
1454 static int
1455 asm_insn_count (body)
1456 rtx body;
1458 const char *template;
1459 int count = 1;
1461 if (GET_CODE (body) == ASM_INPUT)
1462 template = XSTR (body, 0);
1463 else
1464 template = decode_asm_operands (body, NULL, NULL, NULL, NULL);
1466 for (; *template; template++)
1467 if (IS_ASM_LOGICAL_LINE_SEPARATOR (*template) || *template == '\n')
1468 count++;
1470 return count;
1472 #endif
1474 /* Output assembler code for the start of a function,
1475 and initialize some of the variables in this file
1476 for the new function. The label for the function and associated
1477 assembler pseudo-ops have already been output in `assemble_start_function'.
1479 FIRST is the first insn of the rtl for the function being compiled.
1480 FILE is the file to write assembler code to.
1481 OPTIMIZE is nonzero if we should eliminate redundant
1482 test and compare insns. */
1484 void
1485 final_start_function (first, file, optimize)
1486 rtx first;
1487 FILE *file;
1488 int optimize ATTRIBUTE_UNUSED;
1490 block_depth = 0;
1492 this_is_asm_operands = 0;
1494 #ifdef NON_SAVING_SETJMP
1495 /* A function that calls setjmp should save and restore all the
1496 call-saved registers on a system where longjmp clobbers them. */
1497 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
1499 int i;
1501 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
1502 if (!call_used_regs[i])
1503 regs_ever_live[i] = 1;
1505 #endif
1507 if (NOTE_LINE_NUMBER (first) != NOTE_INSN_DELETED)
1508 notice_source_line (first);
1509 high_block_linenum = high_function_linenum = last_linenum;
1511 (*debug_hooks->begin_prologue) (last_linenum, last_filename);
1513 #if defined (DWARF2_UNWIND_INFO) || defined (IA64_UNWIND_INFO)
1514 if (write_symbols != DWARF2_DEBUG && write_symbols != VMS_AND_DWARF2_DEBUG)
1515 dwarf2out_begin_prologue (0, NULL);
1516 #endif
1518 #ifdef LEAF_REG_REMAP
1519 if (current_function_uses_only_leaf_regs)
1520 leaf_renumber_regs (first);
1521 #endif
1523 /* The Sun386i and perhaps other machines don't work right
1524 if the profiling code comes after the prologue. */
1525 #ifdef PROFILE_BEFORE_PROLOGUE
1526 if (current_function_profile)
1527 profile_function (file);
1528 #endif /* PROFILE_BEFORE_PROLOGUE */
1530 #if defined (DWARF2_UNWIND_INFO) && defined (HAVE_prologue)
1531 if (dwarf2out_do_frame ())
1532 dwarf2out_frame_debug (NULL_RTX);
1533 #endif
1535 /* If debugging, assign block numbers to all of the blocks in this
1536 function. */
1537 if (write_symbols)
1539 remove_unnecessary_notes ();
1540 reorder_blocks ();
1541 number_blocks (current_function_decl);
1542 /* We never actually put out begin/end notes for the top-level
1543 block in the function. But, conceptually, that block is
1544 always needed. */
1545 TREE_ASM_WRITTEN (DECL_INITIAL (current_function_decl)) = 1;
1548 /* First output the function prologue: code to set up the stack frame. */
1549 (*targetm.asm_out.function_prologue) (file, get_frame_size ());
1551 #ifdef VMS_DEBUGGING_INFO
1552 /* Output label after the prologue of the function. */
1553 if (write_symbols == VMS_DEBUG || write_symbols == VMS_AND_DWARF2_DEBUG)
1554 vmsdbgout_after_prologue ();
1555 #endif
1557 /* If the machine represents the prologue as RTL, the profiling code must
1558 be emitted when NOTE_INSN_PROLOGUE_END is scanned. */
1559 #ifdef HAVE_prologue
1560 if (! HAVE_prologue)
1561 #endif
1562 profile_after_prologue (file);
1565 static void
1566 profile_after_prologue (file)
1567 FILE *file ATTRIBUTE_UNUSED;
1569 #ifndef PROFILE_BEFORE_PROLOGUE
1570 if (current_function_profile)
1571 profile_function (file);
1572 #endif /* not PROFILE_BEFORE_PROLOGUE */
1575 static void
1576 profile_function (file)
1577 FILE *file ATTRIBUTE_UNUSED;
1579 #ifndef NO_PROFILE_COUNTERS
1580 int align = MIN (BIGGEST_ALIGNMENT, LONG_TYPE_SIZE);
1581 #endif
1582 #if defined(ASM_OUTPUT_REG_PUSH)
1583 #if defined(STRUCT_VALUE_INCOMING_REGNUM) || defined(STRUCT_VALUE_REGNUM)
1584 int sval = current_function_returns_struct;
1585 #endif
1586 #if defined(STATIC_CHAIN_INCOMING_REGNUM) || defined(STATIC_CHAIN_REGNUM)
1587 int cxt = current_function_needs_context;
1588 #endif
1589 #endif /* ASM_OUTPUT_REG_PUSH */
1591 #ifndef NO_PROFILE_COUNTERS
1592 data_section ();
1593 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
1594 ASM_OUTPUT_INTERNAL_LABEL (file, "LP", current_function_profile_label_no);
1595 assemble_integer (const0_rtx, LONG_TYPE_SIZE / BITS_PER_UNIT, align, 1);
1596 #endif
1598 function_section (current_function_decl);
1600 #if defined(STRUCT_VALUE_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1601 if (sval)
1602 ASM_OUTPUT_REG_PUSH (file, STRUCT_VALUE_INCOMING_REGNUM);
1603 #else
1604 #if defined(STRUCT_VALUE_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1605 if (sval)
1607 ASM_OUTPUT_REG_PUSH (file, STRUCT_VALUE_REGNUM);
1609 #endif
1610 #endif
1612 #if defined(STATIC_CHAIN_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1613 if (cxt)
1614 ASM_OUTPUT_REG_PUSH (file, STATIC_CHAIN_INCOMING_REGNUM);
1615 #else
1616 #if defined(STATIC_CHAIN_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1617 if (cxt)
1619 ASM_OUTPUT_REG_PUSH (file, STATIC_CHAIN_REGNUM);
1621 #endif
1622 #endif
1624 FUNCTION_PROFILER (file, current_function_profile_label_no);
1626 #if defined(STATIC_CHAIN_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1627 if (cxt)
1628 ASM_OUTPUT_REG_POP (file, STATIC_CHAIN_INCOMING_REGNUM);
1629 #else
1630 #if defined(STATIC_CHAIN_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1631 if (cxt)
1633 ASM_OUTPUT_REG_POP (file, STATIC_CHAIN_REGNUM);
1635 #endif
1636 #endif
1638 #if defined(STRUCT_VALUE_INCOMING_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1639 if (sval)
1640 ASM_OUTPUT_REG_POP (file, STRUCT_VALUE_INCOMING_REGNUM);
1641 #else
1642 #if defined(STRUCT_VALUE_REGNUM) && defined(ASM_OUTPUT_REG_PUSH)
1643 if (sval)
1645 ASM_OUTPUT_REG_POP (file, STRUCT_VALUE_REGNUM);
1647 #endif
1648 #endif
1651 /* Output assembler code for the end of a function.
1652 For clarity, args are same as those of `final_start_function'
1653 even though not all of them are needed. */
1655 void
1656 final_end_function ()
1658 app_disable ();
1660 (*debug_hooks->end_function) (high_function_linenum);
1662 /* Finally, output the function epilogue:
1663 code to restore the stack frame and return to the caller. */
1664 (*targetm.asm_out.function_epilogue) (asm_out_file, get_frame_size ());
1666 /* And debug output. */
1667 (*debug_hooks->end_epilogue) ();
1669 #if defined (DWARF2_UNWIND_INFO)
1670 if (write_symbols != DWARF2_DEBUG && write_symbols != VMS_AND_DWARF2_DEBUG
1671 && dwarf2out_do_frame ())
1672 dwarf2out_end_epilogue ();
1673 #endif
1676 /* Output assembler code for some insns: all or part of a function.
1677 For description of args, see `final_start_function', above.
1679 PRESCAN is 1 if we are not really outputting,
1680 just scanning as if we were outputting.
1681 Prescanning deletes and rearranges insns just like ordinary output.
1682 PRESCAN is -2 if we are outputting after having prescanned.
1683 In this case, don't try to delete or rearrange insns
1684 because that has already been done.
1685 Prescanning is done only on certain machines. */
1687 void
1688 final (first, file, optimize, prescan)
1689 rtx first;
1690 FILE *file;
1691 int optimize;
1692 int prescan;
1694 rtx insn;
1695 int max_line = 0;
1696 int max_uid = 0;
1698 last_ignored_compare = 0;
1699 new_block = 1;
1701 /* Make a map indicating which line numbers appear in this function.
1702 When producing SDB debugging info, delete troublesome line number
1703 notes from inlined functions in other files as well as duplicate
1704 line number notes. */
1705 #ifdef SDB_DEBUGGING_INFO
1706 if (write_symbols == SDB_DEBUG)
1708 rtx last = 0;
1709 for (insn = first; insn; insn = NEXT_INSN (insn))
1710 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
1712 if ((RTX_INTEGRATED_P (insn)
1713 && strcmp (NOTE_SOURCE_FILE (insn), main_input_filename) != 0)
1714 || (last != 0
1715 && NOTE_LINE_NUMBER (insn) == NOTE_LINE_NUMBER (last)
1716 && NOTE_SOURCE_FILE (insn) == NOTE_SOURCE_FILE (last)))
1718 delete_insn (insn); /* Use delete_note. */
1719 continue;
1721 last = insn;
1722 if (NOTE_LINE_NUMBER (insn) > max_line)
1723 max_line = NOTE_LINE_NUMBER (insn);
1726 else
1727 #endif
1729 for (insn = first; insn; insn = NEXT_INSN (insn))
1730 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > max_line)
1731 max_line = NOTE_LINE_NUMBER (insn);
1734 line_note_exists = (char *) xcalloc (max_line + 1, sizeof (char));
1736 for (insn = first; insn; insn = NEXT_INSN (insn))
1738 if (INSN_UID (insn) > max_uid) /* find largest UID */
1739 max_uid = INSN_UID (insn);
1740 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
1741 line_note_exists[NOTE_LINE_NUMBER (insn)] = 1;
1742 #ifdef HAVE_cc0
1743 /* If CC tracking across branches is enabled, record the insn which
1744 jumps to each branch only reached from one place. */
1745 if (optimize && GET_CODE (insn) == JUMP_INSN)
1747 rtx lab = JUMP_LABEL (insn);
1748 if (lab && LABEL_NUSES (lab) == 1)
1750 LABEL_REFS (lab) = insn;
1753 #endif
1756 init_recog ();
1758 CC_STATUS_INIT;
1760 /* Output the insns. */
1761 for (insn = NEXT_INSN (first); insn;)
1763 #ifdef HAVE_ATTR_length
1764 if ((unsigned) INSN_UID (insn) >= INSN_ADDRESSES_SIZE ())
1766 #ifdef STACK_REGS
1767 /* Irritatingly, the reg-stack pass is creating new instructions
1768 and because of REG_DEAD note abuse it has to run after
1769 shorten_branches. Fake address of -1 then. */
1770 insn_current_address = -1;
1771 #else
1772 /* This can be triggered by bugs elsewhere in the compiler if
1773 new insns are created after init_insn_lengths is called. */
1774 abort ();
1775 #endif
1777 else
1778 insn_current_address = INSN_ADDRESSES (INSN_UID (insn));
1779 #endif /* HAVE_ATTR_length */
1781 insn = final_scan_insn (insn, file, optimize, prescan, 0);
1784 free (line_note_exists);
1785 line_note_exists = NULL;
1788 const char *
1789 get_insn_template (code, insn)
1790 int code;
1791 rtx insn;
1793 const void *output = insn_data[code].output;
1794 switch (insn_data[code].output_format)
1796 case INSN_OUTPUT_FORMAT_SINGLE:
1797 return (const char *) output;
1798 case INSN_OUTPUT_FORMAT_MULTI:
1799 return ((const char *const *) output)[which_alternative];
1800 case INSN_OUTPUT_FORMAT_FUNCTION:
1801 if (insn == NULL)
1802 abort ();
1803 return (*(insn_output_fn) output) (recog_data.operand, insn);
1805 default:
1806 abort ();
1810 /* The final scan for one insn, INSN.
1811 Args are same as in `final', except that INSN
1812 is the insn being scanned.
1813 Value returned is the next insn to be scanned.
1815 NOPEEPHOLES is the flag to disallow peephole processing (currently
1816 used for within delayed branch sequence output). */
1819 final_scan_insn (insn, file, optimize, prescan, nopeepholes)
1820 rtx insn;
1821 FILE *file;
1822 int optimize ATTRIBUTE_UNUSED;
1823 int prescan;
1824 int nopeepholes ATTRIBUTE_UNUSED;
1826 #ifdef HAVE_cc0
1827 rtx set;
1828 #endif
1830 insn_counter++;
1832 /* Ignore deleted insns. These can occur when we split insns (due to a
1833 template of "#") while not optimizing. */
1834 if (INSN_DELETED_P (insn))
1835 return NEXT_INSN (insn);
1837 switch (GET_CODE (insn))
1839 case NOTE:
1840 if (prescan > 0)
1841 break;
1843 switch (NOTE_LINE_NUMBER (insn))
1845 case NOTE_INSN_DELETED:
1846 case NOTE_INSN_LOOP_BEG:
1847 case NOTE_INSN_LOOP_END:
1848 case NOTE_INSN_LOOP_END_TOP_COND:
1849 case NOTE_INSN_LOOP_CONT:
1850 case NOTE_INSN_LOOP_VTOP:
1851 case NOTE_INSN_FUNCTION_END:
1852 case NOTE_INSN_REPEATED_LINE_NUMBER:
1853 case NOTE_INSN_RANGE_BEG:
1854 case NOTE_INSN_RANGE_END:
1855 case NOTE_INSN_LIVE:
1856 case NOTE_INSN_EXPECTED_VALUE:
1857 break;
1859 case NOTE_INSN_BASIC_BLOCK:
1860 #ifdef IA64_UNWIND_INFO
1861 IA64_UNWIND_EMIT (asm_out_file, insn);
1862 #endif
1863 if (flag_debug_asm)
1864 fprintf (asm_out_file, "\t%s basic block %d\n",
1865 ASM_COMMENT_START, NOTE_BASIC_BLOCK (insn)->index);
1866 break;
1868 case NOTE_INSN_EH_REGION_BEG:
1869 ASM_OUTPUT_DEBUG_LABEL (asm_out_file, "LEHB",
1870 NOTE_EH_HANDLER (insn));
1871 break;
1873 case NOTE_INSN_EH_REGION_END:
1874 ASM_OUTPUT_DEBUG_LABEL (asm_out_file, "LEHE",
1875 NOTE_EH_HANDLER (insn));
1876 break;
1878 case NOTE_INSN_PROLOGUE_END:
1879 (*targetm.asm_out.function_end_prologue) (file);
1880 profile_after_prologue (file);
1881 break;
1883 case NOTE_INSN_EPILOGUE_BEG:
1884 (*targetm.asm_out.function_begin_epilogue) (file);
1885 break;
1887 case NOTE_INSN_FUNCTION_BEG:
1888 app_disable ();
1889 (*debug_hooks->end_prologue) (last_linenum);
1890 break;
1892 case NOTE_INSN_BLOCK_BEG:
1893 if (debug_info_level == DINFO_LEVEL_NORMAL
1894 || debug_info_level == DINFO_LEVEL_VERBOSE
1895 || write_symbols == DWARF_DEBUG
1896 || write_symbols == DWARF2_DEBUG
1897 || write_symbols == VMS_AND_DWARF2_DEBUG
1898 || write_symbols == VMS_DEBUG)
1900 int n = BLOCK_NUMBER (NOTE_BLOCK (insn));
1902 app_disable ();
1903 ++block_depth;
1904 high_block_linenum = last_linenum;
1906 /* Output debugging info about the symbol-block beginning. */
1907 (*debug_hooks->begin_block) (last_linenum, n);
1909 /* Mark this block as output. */
1910 TREE_ASM_WRITTEN (NOTE_BLOCK (insn)) = 1;
1912 break;
1914 case NOTE_INSN_BLOCK_END:
1915 if (debug_info_level == DINFO_LEVEL_NORMAL
1916 || debug_info_level == DINFO_LEVEL_VERBOSE
1917 || write_symbols == DWARF_DEBUG
1918 || write_symbols == DWARF2_DEBUG
1919 || write_symbols == VMS_AND_DWARF2_DEBUG
1920 || write_symbols == VMS_DEBUG)
1922 int n = BLOCK_NUMBER (NOTE_BLOCK (insn));
1924 app_disable ();
1926 /* End of a symbol-block. */
1927 --block_depth;
1928 if (block_depth < 0)
1929 abort ();
1931 (*debug_hooks->end_block) (high_block_linenum, n);
1933 break;
1935 case NOTE_INSN_DELETED_LABEL:
1936 /* Emit the label. We may have deleted the CODE_LABEL because
1937 the label could be proved to be unreachable, though still
1938 referenced (in the form of having its address taken. */
1939 ASM_OUTPUT_DEBUG_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
1940 break;
1942 case 0:
1943 break;
1945 default:
1946 if (NOTE_LINE_NUMBER (insn) <= 0)
1947 abort ();
1949 /* This note is a line-number. */
1951 rtx note;
1952 int note_after = 0;
1954 /* If there is anything real after this note, output it.
1955 If another line note follows, omit this one. */
1956 for (note = NEXT_INSN (insn); note; note = NEXT_INSN (note))
1958 if (GET_CODE (note) != NOTE && GET_CODE (note) != CODE_LABEL)
1959 break;
1961 /* These types of notes can be significant
1962 so make sure the preceding line number stays. */
1963 else if (GET_CODE (note) == NOTE
1964 && (NOTE_LINE_NUMBER (note) == NOTE_INSN_BLOCK_BEG
1965 || NOTE_LINE_NUMBER (note) == NOTE_INSN_BLOCK_END
1966 || NOTE_LINE_NUMBER (note) == NOTE_INSN_FUNCTION_BEG))
1967 break;
1968 else if (GET_CODE (note) == NOTE && NOTE_LINE_NUMBER (note) > 0)
1970 /* Another line note follows; we can delete this note
1971 if no intervening line numbers have notes elsewhere. */
1972 int num;
1973 for (num = NOTE_LINE_NUMBER (insn) + 1;
1974 num < NOTE_LINE_NUMBER (note);
1975 num++)
1976 if (line_note_exists[num])
1977 break;
1979 if (num >= NOTE_LINE_NUMBER (note))
1980 note_after = 1;
1981 break;
1985 /* Output this line note if it is the first or the last line
1986 note in a row. */
1987 if (!note_after)
1989 notice_source_line (insn);
1990 (*debug_hooks->source_line) (last_linenum, last_filename);
1993 break;
1995 break;
1997 case BARRIER:
1998 #if defined (DWARF2_UNWIND_INFO)
1999 if (dwarf2out_do_frame ())
2000 dwarf2out_frame_debug (insn);
2001 #endif
2002 break;
2004 case CODE_LABEL:
2005 /* The target port might emit labels in the output function for
2006 some insn, e.g. sh.c output_branchy_insn. */
2007 if (CODE_LABEL_NUMBER (insn) <= max_labelno)
2009 int align = LABEL_TO_ALIGNMENT (insn);
2010 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
2011 int max_skip = LABEL_TO_MAX_SKIP (insn);
2012 #endif
2014 if (align && NEXT_INSN (insn))
2016 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
2017 ASM_OUTPUT_MAX_SKIP_ALIGN (file, align, max_skip);
2018 #else
2019 ASM_OUTPUT_ALIGN (file, align);
2020 #endif
2023 #ifdef HAVE_cc0
2024 CC_STATUS_INIT;
2025 /* If this label is reached from only one place, set the condition
2026 codes from the instruction just before the branch. */
2028 /* Disabled because some insns set cc_status in the C output code
2029 and NOTICE_UPDATE_CC alone can set incorrect status. */
2030 if (0 /* optimize && LABEL_NUSES (insn) == 1*/)
2032 rtx jump = LABEL_REFS (insn);
2033 rtx barrier = prev_nonnote_insn (insn);
2034 rtx prev;
2035 /* If the LABEL_REFS field of this label has been set to point
2036 at a branch, the predecessor of the branch is a regular
2037 insn, and that branch is the only way to reach this label,
2038 set the condition codes based on the branch and its
2039 predecessor. */
2040 if (barrier && GET_CODE (barrier) == BARRIER
2041 && jump && GET_CODE (jump) == JUMP_INSN
2042 && (prev = prev_nonnote_insn (jump))
2043 && GET_CODE (prev) == INSN)
2045 NOTICE_UPDATE_CC (PATTERN (prev), prev);
2046 NOTICE_UPDATE_CC (PATTERN (jump), jump);
2049 #endif
2050 if (prescan > 0)
2051 break;
2052 new_block = 1;
2054 #ifdef FINAL_PRESCAN_LABEL
2055 FINAL_PRESCAN_INSN (insn, NULL, 0);
2056 #endif
2058 if (LABEL_NAME (insn))
2059 (*debug_hooks->label) (insn);
2061 if (app_on)
2063 fputs (ASM_APP_OFF, file);
2064 app_on = 0;
2066 if (NEXT_INSN (insn) != 0
2067 && GET_CODE (NEXT_INSN (insn)) == JUMP_INSN)
2069 rtx nextbody = PATTERN (NEXT_INSN (insn));
2071 /* If this label is followed by a jump-table,
2072 make sure we put the label in the read-only section. Also
2073 possibly write the label and jump table together. */
2075 if (GET_CODE (nextbody) == ADDR_VEC
2076 || GET_CODE (nextbody) == ADDR_DIFF_VEC)
2078 #if defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC)
2079 /* In this case, the case vector is being moved by the
2080 target, so don't output the label at all. Leave that
2081 to the back end macros. */
2082 #else
2083 if (! JUMP_TABLES_IN_TEXT_SECTION)
2085 int log_align;
2087 readonly_data_section ();
2089 #ifdef ADDR_VEC_ALIGN
2090 log_align = ADDR_VEC_ALIGN (NEXT_INSN (insn));
2091 #else
2092 log_align = exact_log2 (BIGGEST_ALIGNMENT / BITS_PER_UNIT);
2093 #endif
2094 ASM_OUTPUT_ALIGN (file, log_align);
2096 else
2097 function_section (current_function_decl);
2099 #ifdef ASM_OUTPUT_CASE_LABEL
2100 ASM_OUTPUT_CASE_LABEL (file, "L", CODE_LABEL_NUMBER (insn),
2101 NEXT_INSN (insn));
2102 #else
2103 if (LABEL_ALTERNATE_NAME (insn))
2104 ASM_OUTPUT_ALTERNATE_LABEL_NAME (file, insn);
2105 else
2106 ASM_OUTPUT_INTERNAL_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
2107 #endif
2108 #endif
2109 break;
2112 if (LABEL_ALTERNATE_NAME (insn))
2113 ASM_OUTPUT_ALTERNATE_LABEL_NAME (file, insn);
2114 else
2115 ASM_OUTPUT_INTERNAL_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
2116 break;
2118 default:
2120 rtx body = PATTERN (insn);
2121 int insn_code_number;
2122 const char *template;
2123 rtx note;
2125 /* An INSN, JUMP_INSN or CALL_INSN.
2126 First check for special kinds that recog doesn't recognize. */
2128 if (GET_CODE (body) == USE /* These are just declarations */
2129 || GET_CODE (body) == CLOBBER)
2130 break;
2132 #ifdef HAVE_cc0
2133 /* If there is a REG_CC_SETTER note on this insn, it means that
2134 the setting of the condition code was done in the delay slot
2135 of the insn that branched here. So recover the cc status
2136 from the insn that set it. */
2138 note = find_reg_note (insn, REG_CC_SETTER, NULL_RTX);
2139 if (note)
2141 NOTICE_UPDATE_CC (PATTERN (XEXP (note, 0)), XEXP (note, 0));
2142 cc_prev_status = cc_status;
2144 #endif
2146 /* Detect insns that are really jump-tables
2147 and output them as such. */
2149 if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
2151 #if !(defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC))
2152 int vlen, idx;
2153 #endif
2155 if (prescan > 0)
2156 break;
2158 if (app_on)
2160 fputs (ASM_APP_OFF, file);
2161 app_on = 0;
2164 #if defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC)
2165 if (GET_CODE (body) == ADDR_VEC)
2167 #ifdef ASM_OUTPUT_ADDR_VEC
2168 ASM_OUTPUT_ADDR_VEC (PREV_INSN (insn), body);
2169 #else
2170 abort ();
2171 #endif
2173 else
2175 #ifdef ASM_OUTPUT_ADDR_DIFF_VEC
2176 ASM_OUTPUT_ADDR_DIFF_VEC (PREV_INSN (insn), body);
2177 #else
2178 abort ();
2179 #endif
2181 #else
2182 vlen = XVECLEN (body, GET_CODE (body) == ADDR_DIFF_VEC);
2183 for (idx = 0; idx < vlen; idx++)
2185 if (GET_CODE (body) == ADDR_VEC)
2187 #ifdef ASM_OUTPUT_ADDR_VEC_ELT
2188 ASM_OUTPUT_ADDR_VEC_ELT
2189 (file, CODE_LABEL_NUMBER (XEXP (XVECEXP (body, 0, idx), 0)));
2190 #else
2191 abort ();
2192 #endif
2194 else
2196 #ifdef ASM_OUTPUT_ADDR_DIFF_ELT
2197 ASM_OUTPUT_ADDR_DIFF_ELT
2198 (file,
2199 body,
2200 CODE_LABEL_NUMBER (XEXP (XVECEXP (body, 1, idx), 0)),
2201 CODE_LABEL_NUMBER (XEXP (XEXP (body, 0), 0)));
2202 #else
2203 abort ();
2204 #endif
2207 #ifdef ASM_OUTPUT_CASE_END
2208 ASM_OUTPUT_CASE_END (file,
2209 CODE_LABEL_NUMBER (PREV_INSN (insn)),
2210 insn);
2211 #endif
2212 #endif
2214 function_section (current_function_decl);
2216 break;
2219 if (GET_CODE (body) == ASM_INPUT)
2221 const char *string = XSTR (body, 0);
2223 /* There's no telling what that did to the condition codes. */
2224 CC_STATUS_INIT;
2225 if (prescan > 0)
2226 break;
2228 if (string[0])
2230 if (! app_on)
2232 fputs (ASM_APP_ON, file);
2233 app_on = 1;
2235 fprintf (asm_out_file, "\t%s\n", string);
2237 break;
2240 /* Detect `asm' construct with operands. */
2241 if (asm_noperands (body) >= 0)
2243 unsigned int noperands = asm_noperands (body);
2244 rtx *ops = (rtx *) alloca (noperands * sizeof (rtx));
2245 const char *string;
2247 /* There's no telling what that did to the condition codes. */
2248 CC_STATUS_INIT;
2249 if (prescan > 0)
2250 break;
2252 /* Get out the operand values. */
2253 string = decode_asm_operands (body, ops, NULL, NULL, NULL);
2254 /* Inhibit aborts on what would otherwise be compiler bugs. */
2255 insn_noperands = noperands;
2256 this_is_asm_operands = insn;
2258 /* Output the insn using them. */
2259 if (string[0])
2261 if (! app_on)
2263 fputs (ASM_APP_ON, file);
2264 app_on = 1;
2266 output_asm_insn (string, ops);
2269 this_is_asm_operands = 0;
2270 break;
2273 if (prescan <= 0 && app_on)
2275 fputs (ASM_APP_OFF, file);
2276 app_on = 0;
2279 if (GET_CODE (body) == SEQUENCE)
2281 /* A delayed-branch sequence */
2282 int i;
2283 rtx next;
2285 if (prescan > 0)
2286 break;
2287 final_sequence = body;
2289 /* The first insn in this SEQUENCE might be a JUMP_INSN that will
2290 force the restoration of a comparison that was previously
2291 thought unnecessary. If that happens, cancel this sequence
2292 and cause that insn to be restored. */
2294 next = final_scan_insn (XVECEXP (body, 0, 0), file, 0, prescan, 1);
2295 if (next != XVECEXP (body, 0, 1))
2297 final_sequence = 0;
2298 return next;
2301 for (i = 1; i < XVECLEN (body, 0); i++)
2303 rtx insn = XVECEXP (body, 0, i);
2304 rtx next = NEXT_INSN (insn);
2305 /* We loop in case any instruction in a delay slot gets
2306 split. */
2308 insn = final_scan_insn (insn, file, 0, prescan, 1);
2309 while (insn != next);
2311 #ifdef DBR_OUTPUT_SEQEND
2312 DBR_OUTPUT_SEQEND (file);
2313 #endif
2314 final_sequence = 0;
2316 /* If the insn requiring the delay slot was a CALL_INSN, the
2317 insns in the delay slot are actually executed before the
2318 called function. Hence we don't preserve any CC-setting
2319 actions in these insns and the CC must be marked as being
2320 clobbered by the function. */
2321 if (GET_CODE (XVECEXP (body, 0, 0)) == CALL_INSN)
2323 CC_STATUS_INIT;
2325 break;
2328 /* We have a real machine instruction as rtl. */
2330 body = PATTERN (insn);
2332 #ifdef HAVE_cc0
2333 set = single_set (insn);
2335 /* Check for redundant test and compare instructions
2336 (when the condition codes are already set up as desired).
2337 This is done only when optimizing; if not optimizing,
2338 it should be possible for the user to alter a variable
2339 with the debugger in between statements
2340 and the next statement should reexamine the variable
2341 to compute the condition codes. */
2343 if (optimize)
2345 #if 0
2346 rtx set = single_set (insn);
2347 #endif
2349 if (set
2350 && GET_CODE (SET_DEST (set)) == CC0
2351 && insn != last_ignored_compare)
2353 if (GET_CODE (SET_SRC (set)) == SUBREG)
2354 SET_SRC (set) = alter_subreg (&SET_SRC (set));
2355 else if (GET_CODE (SET_SRC (set)) == COMPARE)
2357 if (GET_CODE (XEXP (SET_SRC (set), 0)) == SUBREG)
2358 XEXP (SET_SRC (set), 0)
2359 = alter_subreg (&XEXP (SET_SRC (set), 0));
2360 if (GET_CODE (XEXP (SET_SRC (set), 1)) == SUBREG)
2361 XEXP (SET_SRC (set), 1)
2362 = alter_subreg (&XEXP (SET_SRC (set), 1));
2364 if ((cc_status.value1 != 0
2365 && rtx_equal_p (SET_SRC (set), cc_status.value1))
2366 || (cc_status.value2 != 0
2367 && rtx_equal_p (SET_SRC (set), cc_status.value2)))
2369 /* Don't delete insn if it has an addressing side-effect. */
2370 if (! FIND_REG_INC_NOTE (insn, NULL_RTX)
2371 /* or if anything in it is volatile. */
2372 && ! volatile_refs_p (PATTERN (insn)))
2374 /* We don't really delete the insn; just ignore it. */
2375 last_ignored_compare = insn;
2376 break;
2381 #endif
2383 #ifndef STACK_REGS
2384 /* Don't bother outputting obvious no-ops, even without -O.
2385 This optimization is fast and doesn't interfere with debugging.
2386 Don't do this if the insn is in a delay slot, since this
2387 will cause an improper number of delay insns to be written. */
2388 if (final_sequence == 0
2389 && prescan >= 0
2390 && GET_CODE (insn) == INSN && GET_CODE (body) == SET
2391 && GET_CODE (SET_SRC (body)) == REG
2392 && GET_CODE (SET_DEST (body)) == REG
2393 && REGNO (SET_SRC (body)) == REGNO (SET_DEST (body)))
2394 break;
2395 #endif
2397 #ifdef HAVE_cc0
2398 /* If this is a conditional branch, maybe modify it
2399 if the cc's are in a nonstandard state
2400 so that it accomplishes the same thing that it would
2401 do straightforwardly if the cc's were set up normally. */
2403 if (cc_status.flags != 0
2404 && GET_CODE (insn) == JUMP_INSN
2405 && GET_CODE (body) == SET
2406 && SET_DEST (body) == pc_rtx
2407 && GET_CODE (SET_SRC (body)) == IF_THEN_ELSE
2408 && GET_RTX_CLASS (GET_CODE (XEXP (SET_SRC (body), 0))) == '<'
2409 && XEXP (XEXP (SET_SRC (body), 0), 0) == cc0_rtx
2410 /* This is done during prescan; it is not done again
2411 in final scan when prescan has been done. */
2412 && prescan >= 0)
2414 /* This function may alter the contents of its argument
2415 and clear some of the cc_status.flags bits.
2416 It may also return 1 meaning condition now always true
2417 or -1 meaning condition now always false
2418 or 2 meaning condition nontrivial but altered. */
2419 int result = alter_cond (XEXP (SET_SRC (body), 0));
2420 /* If condition now has fixed value, replace the IF_THEN_ELSE
2421 with its then-operand or its else-operand. */
2422 if (result == 1)
2423 SET_SRC (body) = XEXP (SET_SRC (body), 1);
2424 if (result == -1)
2425 SET_SRC (body) = XEXP (SET_SRC (body), 2);
2427 /* The jump is now either unconditional or a no-op.
2428 If it has become a no-op, don't try to output it.
2429 (It would not be recognized.) */
2430 if (SET_SRC (body) == pc_rtx)
2432 delete_insn (insn);
2433 break;
2435 else if (GET_CODE (SET_SRC (body)) == RETURN)
2436 /* Replace (set (pc) (return)) with (return). */
2437 PATTERN (insn) = body = SET_SRC (body);
2439 /* Rerecognize the instruction if it has changed. */
2440 if (result != 0)
2441 INSN_CODE (insn) = -1;
2444 /* Make same adjustments to instructions that examine the
2445 condition codes without jumping and instructions that
2446 handle conditional moves (if this machine has either one). */
2448 if (cc_status.flags != 0
2449 && set != 0)
2451 rtx cond_rtx, then_rtx, else_rtx;
2453 if (GET_CODE (insn) != JUMP_INSN
2454 && GET_CODE (SET_SRC (set)) == IF_THEN_ELSE)
2456 cond_rtx = XEXP (SET_SRC (set), 0);
2457 then_rtx = XEXP (SET_SRC (set), 1);
2458 else_rtx = XEXP (SET_SRC (set), 2);
2460 else
2462 cond_rtx = SET_SRC (set);
2463 then_rtx = const_true_rtx;
2464 else_rtx = const0_rtx;
2467 switch (GET_CODE (cond_rtx))
2469 case GTU:
2470 case GT:
2471 case LTU:
2472 case LT:
2473 case GEU:
2474 case GE:
2475 case LEU:
2476 case LE:
2477 case EQ:
2478 case NE:
2480 int result;
2481 if (XEXP (cond_rtx, 0) != cc0_rtx)
2482 break;
2483 result = alter_cond (cond_rtx);
2484 if (result == 1)
2485 validate_change (insn, &SET_SRC (set), then_rtx, 0);
2486 else if (result == -1)
2487 validate_change (insn, &SET_SRC (set), else_rtx, 0);
2488 else if (result == 2)
2489 INSN_CODE (insn) = -1;
2490 if (SET_DEST (set) == SET_SRC (set))
2491 delete_insn (insn);
2493 break;
2495 default:
2496 break;
2500 #endif
2502 #ifdef HAVE_peephole
2503 /* Do machine-specific peephole optimizations if desired. */
2505 if (optimize && !flag_no_peephole && !nopeepholes)
2507 rtx next = peephole (insn);
2508 /* When peepholing, if there were notes within the peephole,
2509 emit them before the peephole. */
2510 if (next != 0 && next != NEXT_INSN (insn))
2512 rtx prev = PREV_INSN (insn);
2514 for (note = NEXT_INSN (insn); note != next;
2515 note = NEXT_INSN (note))
2516 final_scan_insn (note, file, optimize, prescan, nopeepholes);
2518 /* In case this is prescan, put the notes
2519 in proper position for later rescan. */
2520 note = NEXT_INSN (insn);
2521 PREV_INSN (note) = prev;
2522 NEXT_INSN (prev) = note;
2523 NEXT_INSN (PREV_INSN (next)) = insn;
2524 PREV_INSN (insn) = PREV_INSN (next);
2525 NEXT_INSN (insn) = next;
2526 PREV_INSN (next) = insn;
2529 /* PEEPHOLE might have changed this. */
2530 body = PATTERN (insn);
2532 #endif
2534 /* Try to recognize the instruction.
2535 If successful, verify that the operands satisfy the
2536 constraints for the instruction. Crash if they don't,
2537 since `reload' should have changed them so that they do. */
2539 insn_code_number = recog_memoized (insn);
2540 cleanup_subreg_operands (insn);
2542 /* Dump the insn in the assembly for debugging. */
2543 if (flag_dump_rtl_in_asm)
2545 print_rtx_head = ASM_COMMENT_START;
2546 print_rtl_single (asm_out_file, insn);
2547 print_rtx_head = "";
2550 if (! constrain_operands_cached (1))
2551 fatal_insn_not_found (insn);
2553 /* Some target machines need to prescan each insn before
2554 it is output. */
2556 #ifdef FINAL_PRESCAN_INSN
2557 FINAL_PRESCAN_INSN (insn, recog_data.operand, recog_data.n_operands);
2558 #endif
2560 #ifdef HAVE_conditional_execution
2561 if (GET_CODE (PATTERN (insn)) == COND_EXEC)
2562 current_insn_predicate = COND_EXEC_TEST (PATTERN (insn));
2563 else
2564 current_insn_predicate = NULL_RTX;
2565 #endif
2567 #ifdef HAVE_cc0
2568 cc_prev_status = cc_status;
2570 /* Update `cc_status' for this instruction.
2571 The instruction's output routine may change it further.
2572 If the output routine for a jump insn needs to depend
2573 on the cc status, it should look at cc_prev_status. */
2575 NOTICE_UPDATE_CC (body, insn);
2576 #endif
2578 current_output_insn = debug_insn = insn;
2580 #if defined (DWARF2_UNWIND_INFO)
2581 if (GET_CODE (insn) == CALL_INSN && dwarf2out_do_frame ())
2582 dwarf2out_frame_debug (insn);
2583 #endif
2585 /* Find the proper template for this insn. */
2586 template = get_insn_template (insn_code_number, insn);
2588 /* If the C code returns 0, it means that it is a jump insn
2589 which follows a deleted test insn, and that test insn
2590 needs to be reinserted. */
2591 if (template == 0)
2593 rtx prev;
2595 if (prev_nonnote_insn (insn) != last_ignored_compare)
2596 abort ();
2597 new_block = 0;
2599 /* We have already processed the notes between the setter and
2600 the user. Make sure we don't process them again, this is
2601 particularly important if one of the notes is a block
2602 scope note or an EH note. */
2603 for (prev = insn;
2604 prev != last_ignored_compare;
2605 prev = PREV_INSN (prev))
2607 if (GET_CODE (prev) == NOTE)
2608 delete_insn (prev); /* Use delete_note. */
2611 return prev;
2614 /* If the template is the string "#", it means that this insn must
2615 be split. */
2616 if (template[0] == '#' && template[1] == '\0')
2618 rtx new = try_split (body, insn, 0);
2620 /* If we didn't split the insn, go away. */
2621 if (new == insn && PATTERN (new) == body)
2622 fatal_insn ("could not split insn", insn);
2624 #ifdef HAVE_ATTR_length
2625 /* This instruction should have been split in shorten_branches,
2626 to ensure that we would have valid length info for the
2627 splitees. */
2628 abort ();
2629 #endif
2631 new_block = 0;
2632 return new;
2635 if (prescan > 0)
2636 break;
2638 #ifdef IA64_UNWIND_INFO
2639 IA64_UNWIND_EMIT (asm_out_file, insn);
2640 #endif
2641 /* Output assembler code from the template. */
2643 output_asm_insn (template, recog_data.operand);
2645 #if defined (DWARF2_UNWIND_INFO)
2646 #if defined (HAVE_prologue)
2647 if (GET_CODE (insn) == INSN && dwarf2out_do_frame ())
2648 dwarf2out_frame_debug (insn);
2649 #else
2650 if (!ACCUMULATE_OUTGOING_ARGS
2651 && GET_CODE (insn) == INSN
2652 && dwarf2out_do_frame ())
2653 dwarf2out_frame_debug (insn);
2654 #endif
2655 #endif
2657 #if 0
2658 /* It's not at all clear why we did this and doing so interferes
2659 with tests we'd like to do to use REG_WAS_0 notes, so let's try
2660 with this out. */
2662 /* Mark this insn as having been output. */
2663 INSN_DELETED_P (insn) = 1;
2664 #endif
2666 /* Emit information for vtable gc. */
2667 note = find_reg_note (insn, REG_VTABLE_REF, NULL_RTX);
2668 if (note)
2669 assemble_vtable_entry (XEXP (XEXP (note, 0), 0),
2670 INTVAL (XEXP (XEXP (note, 0), 1)));
2672 current_output_insn = debug_insn = 0;
2675 return NEXT_INSN (insn);
2678 /* Output debugging info to the assembler file FILE
2679 based on the NOTE-insn INSN, assumed to be a line number. */
2681 static void
2682 notice_source_line (insn)
2683 rtx insn;
2685 const char *filename = NOTE_SOURCE_FILE (insn);
2687 last_filename = filename;
2688 last_linenum = NOTE_LINE_NUMBER (insn);
2689 high_block_linenum = MAX (last_linenum, high_block_linenum);
2690 high_function_linenum = MAX (last_linenum, high_function_linenum);
2693 /* For each operand in INSN, simplify (subreg (reg)) so that it refers
2694 directly to the desired hard register. */
2696 void
2697 cleanup_subreg_operands (insn)
2698 rtx insn;
2700 int i;
2701 extract_insn_cached (insn);
2702 for (i = 0; i < recog_data.n_operands; i++)
2704 /* The following test cannot use recog_data.operand when tesing
2705 for a SUBREG: the underlying object might have been changed
2706 already if we are inside a match_operator expression that
2707 matches the else clause. Instead we test the underlying
2708 expression directly. */
2709 if (GET_CODE (*recog_data.operand_loc[i]) == SUBREG)
2710 recog_data.operand[i] = alter_subreg (recog_data.operand_loc[i]);
2711 else if (GET_CODE (recog_data.operand[i]) == PLUS
2712 || GET_CODE (recog_data.operand[i]) == MULT
2713 || GET_CODE (recog_data.operand[i]) == MEM)
2714 recog_data.operand[i] = walk_alter_subreg (recog_data.operand_loc[i]);
2717 for (i = 0; i < recog_data.n_dups; i++)
2719 if (GET_CODE (*recog_data.dup_loc[i]) == SUBREG)
2720 *recog_data.dup_loc[i] = alter_subreg (recog_data.dup_loc[i]);
2721 else if (GET_CODE (*recog_data.dup_loc[i]) == PLUS
2722 || GET_CODE (*recog_data.dup_loc[i]) == MULT
2723 || GET_CODE (*recog_data.dup_loc[i]) == MEM)
2724 *recog_data.dup_loc[i] = walk_alter_subreg (recog_data.dup_loc[i]);
2728 /* If X is a SUBREG, replace it with a REG or a MEM,
2729 based on the thing it is a subreg of. */
2732 alter_subreg (xp)
2733 rtx *xp;
2735 rtx x = *xp;
2736 rtx y = SUBREG_REG (x);
2738 /* simplify_subreg does not remove subreg from volatile references.
2739 We are required to. */
2740 if (GET_CODE (y) == MEM)
2741 *xp = adjust_address (y, GET_MODE (x), SUBREG_BYTE (x));
2742 else
2744 rtx new = simplify_subreg (GET_MODE (x), y, GET_MODE (y),
2745 SUBREG_BYTE (x));
2747 if (new != 0)
2748 *xp = new;
2749 /* Simplify_subreg can't handle some REG cases, but we have to. */
2750 else if (GET_CODE (y) == REG)
2752 unsigned int regno = subreg_hard_regno (x, 1);
2753 PUT_CODE (x, REG);
2754 REGNO (x) = regno;
2755 ORIGINAL_REGNO (x) = ORIGINAL_REGNO (y);
2756 /* This field has a different meaning for REGs and SUBREGs. Make
2757 sure to clear it! */
2758 RTX_FLAG (x, used) = 0;
2760 else
2761 abort ();
2764 return *xp;
2767 /* Do alter_subreg on all the SUBREGs contained in X. */
2769 static rtx
2770 walk_alter_subreg (xp)
2771 rtx *xp;
2773 rtx x = *xp;
2774 switch (GET_CODE (x))
2776 case PLUS:
2777 case MULT:
2778 XEXP (x, 0) = walk_alter_subreg (&XEXP (x, 0));
2779 XEXP (x, 1) = walk_alter_subreg (&XEXP (x, 1));
2780 break;
2782 case MEM:
2783 XEXP (x, 0) = walk_alter_subreg (&XEXP (x, 0));
2784 break;
2786 case SUBREG:
2787 return alter_subreg (xp);
2789 default:
2790 break;
2793 return *xp;
2796 #ifdef HAVE_cc0
2798 /* Given BODY, the body of a jump instruction, alter the jump condition
2799 as required by the bits that are set in cc_status.flags.
2800 Not all of the bits there can be handled at this level in all cases.
2802 The value is normally 0.
2803 1 means that the condition has become always true.
2804 -1 means that the condition has become always false.
2805 2 means that COND has been altered. */
2807 static int
2808 alter_cond (cond)
2809 rtx cond;
2811 int value = 0;
2813 if (cc_status.flags & CC_REVERSED)
2815 value = 2;
2816 PUT_CODE (cond, swap_condition (GET_CODE (cond)));
2819 if (cc_status.flags & CC_INVERTED)
2821 value = 2;
2822 PUT_CODE (cond, reverse_condition (GET_CODE (cond)));
2825 if (cc_status.flags & CC_NOT_POSITIVE)
2826 switch (GET_CODE (cond))
2828 case LE:
2829 case LEU:
2830 case GEU:
2831 /* Jump becomes unconditional. */
2832 return 1;
2834 case GT:
2835 case GTU:
2836 case LTU:
2837 /* Jump becomes no-op. */
2838 return -1;
2840 case GE:
2841 PUT_CODE (cond, EQ);
2842 value = 2;
2843 break;
2845 case LT:
2846 PUT_CODE (cond, NE);
2847 value = 2;
2848 break;
2850 default:
2851 break;
2854 if (cc_status.flags & CC_NOT_NEGATIVE)
2855 switch (GET_CODE (cond))
2857 case GE:
2858 case GEU:
2859 /* Jump becomes unconditional. */
2860 return 1;
2862 case LT:
2863 case LTU:
2864 /* Jump becomes no-op. */
2865 return -1;
2867 case LE:
2868 case LEU:
2869 PUT_CODE (cond, EQ);
2870 value = 2;
2871 break;
2873 case GT:
2874 case GTU:
2875 PUT_CODE (cond, NE);
2876 value = 2;
2877 break;
2879 default:
2880 break;
2883 if (cc_status.flags & CC_NO_OVERFLOW)
2884 switch (GET_CODE (cond))
2886 case GEU:
2887 /* Jump becomes unconditional. */
2888 return 1;
2890 case LEU:
2891 PUT_CODE (cond, EQ);
2892 value = 2;
2893 break;
2895 case GTU:
2896 PUT_CODE (cond, NE);
2897 value = 2;
2898 break;
2900 case LTU:
2901 /* Jump becomes no-op. */
2902 return -1;
2904 default:
2905 break;
2908 if (cc_status.flags & (CC_Z_IN_NOT_N | CC_Z_IN_N))
2909 switch (GET_CODE (cond))
2911 default:
2912 abort ();
2914 case NE:
2915 PUT_CODE (cond, cc_status.flags & CC_Z_IN_N ? GE : LT);
2916 value = 2;
2917 break;
2919 case EQ:
2920 PUT_CODE (cond, cc_status.flags & CC_Z_IN_N ? LT : GE);
2921 value = 2;
2922 break;
2925 if (cc_status.flags & CC_NOT_SIGNED)
2926 /* The flags are valid if signed condition operators are converted
2927 to unsigned. */
2928 switch (GET_CODE (cond))
2930 case LE:
2931 PUT_CODE (cond, LEU);
2932 value = 2;
2933 break;
2935 case LT:
2936 PUT_CODE (cond, LTU);
2937 value = 2;
2938 break;
2940 case GT:
2941 PUT_CODE (cond, GTU);
2942 value = 2;
2943 break;
2945 case GE:
2946 PUT_CODE (cond, GEU);
2947 value = 2;
2948 break;
2950 default:
2951 break;
2954 return value;
2956 #endif
2958 /* Report inconsistency between the assembler template and the operands.
2959 In an `asm', it's the user's fault; otherwise, the compiler's fault. */
2961 void
2962 output_operand_lossage VPARAMS ((const char *msgid, ...))
2964 char *fmt_string;
2965 char *new_message;
2966 const char *pfx_str;
2967 VA_OPEN (ap, msgid);
2968 VA_FIXEDARG (ap, const char *, msgid);
2970 pfx_str = this_is_asm_operands ? _("invalid `asm': ") : "output_operand: ";
2971 asprintf (&fmt_string, "%s%s", pfx_str, _(msgid));
2972 vasprintf (&new_message, fmt_string, ap);
2974 if (this_is_asm_operands)
2975 error_for_asm (this_is_asm_operands, "%s", new_message);
2976 else
2977 internal_error ("%s", new_message);
2979 free (fmt_string);
2980 free (new_message);
2981 VA_CLOSE (ap);
2984 /* Output of assembler code from a template, and its subroutines. */
2986 /* Annotate the assembly with a comment describing the pattern and
2987 alternative used. */
2989 static void
2990 output_asm_name ()
2992 if (debug_insn)
2994 int num = INSN_CODE (debug_insn);
2995 fprintf (asm_out_file, "\t%s %d\t%s",
2996 ASM_COMMENT_START, INSN_UID (debug_insn),
2997 insn_data[num].name);
2998 if (insn_data[num].n_alternatives > 1)
2999 fprintf (asm_out_file, "/%d", which_alternative + 1);
3000 #ifdef HAVE_ATTR_length
3001 fprintf (asm_out_file, "\t[length = %d]",
3002 get_attr_length (debug_insn));
3003 #endif
3004 /* Clear this so only the first assembler insn
3005 of any rtl insn will get the special comment for -dp. */
3006 debug_insn = 0;
3010 /* If OP is a REG or MEM and we can find a MEM_EXPR corresponding to it
3011 or its address, return that expr . Set *PADDRESSP to 1 if the expr
3012 corresponds to the address of the object and 0 if to the object. */
3014 static tree
3015 get_mem_expr_from_op (op, paddressp)
3016 rtx op;
3017 int *paddressp;
3019 tree expr;
3020 int inner_addressp;
3022 *paddressp = 0;
3024 if (GET_CODE (op) == REG && ORIGINAL_REGNO (op) >= FIRST_PSEUDO_REGISTER)
3025 return REGNO_DECL (ORIGINAL_REGNO (op));
3026 else if (GET_CODE (op) != MEM)
3027 return 0;
3029 if (MEM_EXPR (op) != 0)
3030 return MEM_EXPR (op);
3032 /* Otherwise we have an address, so indicate it and look at the address. */
3033 *paddressp = 1;
3034 op = XEXP (op, 0);
3036 /* First check if we have a decl for the address, then look at the right side
3037 if it is a PLUS. Otherwise, strip off arithmetic and keep looking.
3038 But don't allow the address to itself be indirect. */
3039 if ((expr = get_mem_expr_from_op (op, &inner_addressp)) && ! inner_addressp)
3040 return expr;
3041 else if (GET_CODE (op) == PLUS
3042 && (expr = get_mem_expr_from_op (XEXP (op, 1), &inner_addressp)))
3043 return expr;
3045 while (GET_RTX_CLASS (GET_CODE (op)) == '1'
3046 || GET_RTX_CLASS (GET_CODE (op)) == '2')
3047 op = XEXP (op, 0);
3049 expr = get_mem_expr_from_op (op, &inner_addressp);
3050 return inner_addressp ? 0 : expr;
3053 /* Output operand names for assembler instructions. OPERANDS is the
3054 operand vector, OPORDER is the order to write the operands, and NOPS
3055 is the number of operands to write. */
3057 static void
3058 output_asm_operand_names (operands, oporder, nops)
3059 rtx *operands;
3060 int *oporder;
3061 int nops;
3063 int wrote = 0;
3064 int i;
3066 for (i = 0; i < nops; i++)
3068 int addressp;
3069 tree expr = get_mem_expr_from_op (operands[oporder[i]], &addressp);
3071 if (expr)
3073 fprintf (asm_out_file, "%c%s %s",
3074 wrote ? ',' : '\t', wrote ? "" : ASM_COMMENT_START,
3075 addressp ? "*" : "");
3076 print_mem_expr (asm_out_file, expr);
3077 wrote = 1;
3082 /* Output text from TEMPLATE to the assembler output file,
3083 obeying %-directions to substitute operands taken from
3084 the vector OPERANDS.
3086 %N (for N a digit) means print operand N in usual manner.
3087 %lN means require operand N to be a CODE_LABEL or LABEL_REF
3088 and print the label name with no punctuation.
3089 %cN means require operand N to be a constant
3090 and print the constant expression with no punctuation.
3091 %aN means expect operand N to be a memory address
3092 (not a memory reference!) and print a reference
3093 to that address.
3094 %nN means expect operand N to be a constant
3095 and print a constant expression for minus the value
3096 of the operand, with no other punctuation. */
3098 void
3099 output_asm_insn (template, operands)
3100 const char *template;
3101 rtx *operands;
3103 const char *p;
3104 int c;
3105 #ifdef ASSEMBLER_DIALECT
3106 int dialect = 0;
3107 #endif
3108 int oporder[MAX_RECOG_OPERANDS];
3109 char opoutput[MAX_RECOG_OPERANDS];
3110 int ops = 0;
3112 /* An insn may return a null string template
3113 in a case where no assembler code is needed. */
3114 if (*template == 0)
3115 return;
3117 memset (opoutput, 0, sizeof opoutput);
3118 p = template;
3119 putc ('\t', asm_out_file);
3121 #ifdef ASM_OUTPUT_OPCODE
3122 ASM_OUTPUT_OPCODE (asm_out_file, p);
3123 #endif
3125 while ((c = *p++))
3126 switch (c)
3128 case '\n':
3129 if (flag_verbose_asm)
3130 output_asm_operand_names (operands, oporder, ops);
3131 if (flag_print_asm_name)
3132 output_asm_name ();
3134 ops = 0;
3135 memset (opoutput, 0, sizeof opoutput);
3137 putc (c, asm_out_file);
3138 #ifdef ASM_OUTPUT_OPCODE
3139 while ((c = *p) == '\t')
3141 putc (c, asm_out_file);
3142 p++;
3144 ASM_OUTPUT_OPCODE (asm_out_file, p);
3145 #endif
3146 break;
3148 #ifdef ASSEMBLER_DIALECT
3149 case '{':
3151 int i;
3153 if (dialect)
3154 output_operand_lossage ("nested assembly dialect alternatives");
3155 else
3156 dialect = 1;
3158 /* If we want the first dialect, do nothing. Otherwise, skip
3159 DIALECT_NUMBER of strings ending with '|'. */
3160 for (i = 0; i < dialect_number; i++)
3162 while (*p && *p != '}' && *p++ != '|')
3164 if (*p == '}')
3165 break;
3166 if (*p == '|')
3167 p++;
3170 if (*p == '\0')
3171 output_operand_lossage ("unterminated assembly dialect alternative");
3173 break;
3175 case '|':
3176 if (dialect)
3178 /* Skip to close brace. */
3181 if (*p == '\0')
3183 output_operand_lossage ("unterminated assembly dialect alternative");
3184 break;
3187 while (*p++ != '}');
3188 dialect = 0;
3190 else
3191 putc (c, asm_out_file);
3192 break;
3194 case '}':
3195 if (! dialect)
3196 putc (c, asm_out_file);
3197 dialect = 0;
3198 break;
3199 #endif
3201 case '%':
3202 /* %% outputs a single %. */
3203 if (*p == '%')
3205 p++;
3206 putc (c, asm_out_file);
3208 /* %= outputs a number which is unique to each insn in the entire
3209 compilation. This is useful for making local labels that are
3210 referred to more than once in a given insn. */
3211 else if (*p == '=')
3213 p++;
3214 fprintf (asm_out_file, "%d", insn_counter);
3216 /* % followed by a letter and some digits
3217 outputs an operand in a special way depending on the letter.
3218 Letters `acln' are implemented directly.
3219 Other letters are passed to `output_operand' so that
3220 the PRINT_OPERAND macro can define them. */
3221 else if (ISALPHA (*p))
3223 int letter = *p++;
3224 c = atoi (p);
3226 if (! ISDIGIT (*p))
3227 output_operand_lossage ("operand number missing after %%-letter");
3228 else if (this_is_asm_operands
3229 && (c < 0 || (unsigned int) c >= insn_noperands))
3230 output_operand_lossage ("operand number out of range");
3231 else if (letter == 'l')
3232 output_asm_label (operands[c]);
3233 else if (letter == 'a')
3234 output_address (operands[c]);
3235 else if (letter == 'c')
3237 if (CONSTANT_ADDRESS_P (operands[c]))
3238 output_addr_const (asm_out_file, operands[c]);
3239 else
3240 output_operand (operands[c], 'c');
3242 else if (letter == 'n')
3244 if (GET_CODE (operands[c]) == CONST_INT)
3245 fprintf (asm_out_file, HOST_WIDE_INT_PRINT_DEC,
3246 - INTVAL (operands[c]));
3247 else
3249 putc ('-', asm_out_file);
3250 output_addr_const (asm_out_file, operands[c]);
3253 else
3254 output_operand (operands[c], letter);
3256 if (!opoutput[c])
3257 oporder[ops++] = c;
3258 opoutput[c] = 1;
3260 while (ISDIGIT (c = *p))
3261 p++;
3263 /* % followed by a digit outputs an operand the default way. */
3264 else if (ISDIGIT (*p))
3266 c = atoi (p);
3267 if (this_is_asm_operands
3268 && (c < 0 || (unsigned int) c >= insn_noperands))
3269 output_operand_lossage ("operand number out of range");
3270 else
3271 output_operand (operands[c], 0);
3273 if (!opoutput[c])
3274 oporder[ops++] = c;
3275 opoutput[c] = 1;
3277 while (ISDIGIT (c = *p))
3278 p++;
3280 /* % followed by punctuation: output something for that
3281 punctuation character alone, with no operand.
3282 The PRINT_OPERAND macro decides what is actually done. */
3283 #ifdef PRINT_OPERAND_PUNCT_VALID_P
3284 else if (PRINT_OPERAND_PUNCT_VALID_P ((unsigned char) *p))
3285 output_operand (NULL_RTX, *p++);
3286 #endif
3287 else
3288 output_operand_lossage ("invalid %%-code");
3289 break;
3291 default:
3292 putc (c, asm_out_file);
3295 /* Write out the variable names for operands, if we know them. */
3296 if (flag_verbose_asm)
3297 output_asm_operand_names (operands, oporder, ops);
3298 if (flag_print_asm_name)
3299 output_asm_name ();
3301 putc ('\n', asm_out_file);
3304 /* Output a LABEL_REF, or a bare CODE_LABEL, as an assembler symbol. */
3306 void
3307 output_asm_label (x)
3308 rtx x;
3310 char buf[256];
3312 if (GET_CODE (x) == LABEL_REF)
3313 x = XEXP (x, 0);
3314 if (GET_CODE (x) == CODE_LABEL
3315 || (GET_CODE (x) == NOTE
3316 && NOTE_LINE_NUMBER (x) == NOTE_INSN_DELETED_LABEL))
3317 ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
3318 else
3319 output_operand_lossage ("`%%l' operand isn't a label");
3321 assemble_name (asm_out_file, buf);
3324 /* Print operand X using machine-dependent assembler syntax.
3325 The macro PRINT_OPERAND is defined just to control this function.
3326 CODE is a non-digit that preceded the operand-number in the % spec,
3327 such as 'z' if the spec was `%z3'. CODE is 0 if there was no char
3328 between the % and the digits.
3329 When CODE is a non-letter, X is 0.
3331 The meanings of the letters are machine-dependent and controlled
3332 by PRINT_OPERAND. */
3334 static void
3335 output_operand (x, code)
3336 rtx x;
3337 int code ATTRIBUTE_UNUSED;
3339 if (x && GET_CODE (x) == SUBREG)
3340 x = alter_subreg (&x);
3342 /* If X is a pseudo-register, abort now rather than writing trash to the
3343 assembler file. */
3345 if (x && GET_CODE (x) == REG && REGNO (x) >= FIRST_PSEUDO_REGISTER)
3346 abort ();
3348 PRINT_OPERAND (asm_out_file, x, code);
3351 /* Print a memory reference operand for address X
3352 using machine-dependent assembler syntax.
3353 The macro PRINT_OPERAND_ADDRESS exists just to control this function. */
3355 void
3356 output_address (x)
3357 rtx x;
3359 walk_alter_subreg (&x);
3360 PRINT_OPERAND_ADDRESS (asm_out_file, x);
3363 /* Print an integer constant expression in assembler syntax.
3364 Addition and subtraction are the only arithmetic
3365 that may appear in these expressions. */
3367 void
3368 output_addr_const (file, x)
3369 FILE *file;
3370 rtx x;
3372 char buf[256];
3374 restart:
3375 switch (GET_CODE (x))
3377 case PC:
3378 putc ('.', file);
3379 break;
3381 case SYMBOL_REF:
3382 #ifdef ASM_OUTPUT_SYMBOL_REF
3383 ASM_OUTPUT_SYMBOL_REF (file, x);
3384 #else
3385 assemble_name (file, XSTR (x, 0));
3386 #endif
3387 break;
3389 case LABEL_REF:
3390 x = XEXP (x, 0);
3391 /* Fall through. */
3392 case CODE_LABEL:
3393 ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
3394 #ifdef ASM_OUTPUT_LABEL_REF
3395 ASM_OUTPUT_LABEL_REF (file, buf);
3396 #else
3397 assemble_name (file, buf);
3398 #endif
3399 break;
3401 case CONST_INT:
3402 fprintf (file, HOST_WIDE_INT_PRINT_DEC, INTVAL (x));
3403 break;
3405 case CONST:
3406 /* This used to output parentheses around the expression,
3407 but that does not work on the 386 (either ATT or BSD assembler). */
3408 output_addr_const (file, XEXP (x, 0));
3409 break;
3411 case CONST_DOUBLE:
3412 if (GET_MODE (x) == VOIDmode)
3414 /* We can use %d if the number is one word and positive. */
3415 if (CONST_DOUBLE_HIGH (x))
3416 fprintf (file, HOST_WIDE_INT_PRINT_DOUBLE_HEX,
3417 CONST_DOUBLE_HIGH (x), CONST_DOUBLE_LOW (x));
3418 else if (CONST_DOUBLE_LOW (x) < 0)
3419 fprintf (file, HOST_WIDE_INT_PRINT_HEX, CONST_DOUBLE_LOW (x));
3420 else
3421 fprintf (file, HOST_WIDE_INT_PRINT_DEC, CONST_DOUBLE_LOW (x));
3423 else
3424 /* We can't handle floating point constants;
3425 PRINT_OPERAND must handle them. */
3426 output_operand_lossage ("floating constant misused");
3427 break;
3429 case PLUS:
3430 /* Some assemblers need integer constants to appear last (eg masm). */
3431 if (GET_CODE (XEXP (x, 0)) == CONST_INT)
3433 output_addr_const (file, XEXP (x, 1));
3434 if (INTVAL (XEXP (x, 0)) >= 0)
3435 fprintf (file, "+");
3436 output_addr_const (file, XEXP (x, 0));
3438 else
3440 output_addr_const (file, XEXP (x, 0));
3441 if (GET_CODE (XEXP (x, 1)) != CONST_INT
3442 || INTVAL (XEXP (x, 1)) >= 0)
3443 fprintf (file, "+");
3444 output_addr_const (file, XEXP (x, 1));
3446 break;
3448 case MINUS:
3449 /* Avoid outputting things like x-x or x+5-x,
3450 since some assemblers can't handle that. */
3451 x = simplify_subtraction (x);
3452 if (GET_CODE (x) != MINUS)
3453 goto restart;
3455 output_addr_const (file, XEXP (x, 0));
3456 fprintf (file, "-");
3457 if ((GET_CODE (XEXP (x, 1)) == CONST_INT && INTVAL (XEXP (x, 1)) >= 0)
3458 || GET_CODE (XEXP (x, 1)) == PC
3459 || GET_CODE (XEXP (x, 1)) == SYMBOL_REF)
3460 output_addr_const (file, XEXP (x, 1));
3461 else
3463 fputs (targetm.asm_out.open_paren, file);
3464 output_addr_const (file, XEXP (x, 1));
3465 fputs (targetm.asm_out.close_paren, file);
3467 break;
3469 case ZERO_EXTEND:
3470 case SIGN_EXTEND:
3471 case SUBREG:
3472 output_addr_const (file, XEXP (x, 0));
3473 break;
3475 default:
3476 #ifdef OUTPUT_ADDR_CONST_EXTRA
3477 OUTPUT_ADDR_CONST_EXTRA (file, x, fail);
3478 break;
3480 fail:
3481 #endif
3482 output_operand_lossage ("invalid expression as operand");
3486 /* A poor man's fprintf, with the added features of %I, %R, %L, and %U.
3487 %R prints the value of REGISTER_PREFIX.
3488 %L prints the value of LOCAL_LABEL_PREFIX.
3489 %U prints the value of USER_LABEL_PREFIX.
3490 %I prints the value of IMMEDIATE_PREFIX.
3491 %O runs ASM_OUTPUT_OPCODE to transform what follows in the string.
3492 Also supported are %d, %x, %s, %e, %f, %g and %%.
3494 We handle alternate assembler dialects here, just like output_asm_insn. */
3496 void
3497 asm_fprintf VPARAMS ((FILE *file, const char *p, ...))
3499 char buf[10];
3500 char *q, c;
3502 VA_OPEN (argptr, p);
3503 VA_FIXEDARG (argptr, FILE *, file);
3504 VA_FIXEDARG (argptr, const char *, p);
3506 buf[0] = '%';
3508 while ((c = *p++))
3509 switch (c)
3511 #ifdef ASSEMBLER_DIALECT
3512 case '{':
3514 int i;
3516 /* If we want the first dialect, do nothing. Otherwise, skip
3517 DIALECT_NUMBER of strings ending with '|'. */
3518 for (i = 0; i < dialect_number; i++)
3520 while (*p && *p++ != '|')
3523 if (*p == '|')
3524 p++;
3527 break;
3529 case '|':
3530 /* Skip to close brace. */
3531 while (*p && *p++ != '}')
3533 break;
3535 case '}':
3536 break;
3537 #endif
3539 case '%':
3540 c = *p++;
3541 q = &buf[1];
3542 while (ISDIGIT (c) || c == '.')
3544 *q++ = c;
3545 c = *p++;
3547 switch (c)
3549 case '%':
3550 fprintf (file, "%%");
3551 break;
3553 case 'd': case 'i': case 'u':
3554 case 'x': case 'p': case 'X':
3555 case 'o':
3556 *q++ = c;
3557 *q = 0;
3558 fprintf (file, buf, va_arg (argptr, int));
3559 break;
3561 case 'w':
3562 /* This is a prefix to the 'd', 'i', 'u', 'x', 'p', and 'X' cases,
3563 but we do not check for those cases. It means that the value
3564 is a HOST_WIDE_INT, which may be either `int' or `long'. */
3566 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
3567 #else
3568 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
3569 *q++ = 'l';
3570 #else
3571 *q++ = 'l';
3572 *q++ = 'l';
3573 #endif
3574 #endif
3576 *q++ = *p++;
3577 *q = 0;
3578 fprintf (file, buf, va_arg (argptr, HOST_WIDE_INT));
3579 break;
3581 case 'l':
3582 *q++ = c;
3583 *q++ = *p++;
3584 *q = 0;
3585 fprintf (file, buf, va_arg (argptr, long));
3586 break;
3588 case 'e':
3589 case 'f':
3590 case 'g':
3591 *q++ = c;
3592 *q = 0;
3593 fprintf (file, buf, va_arg (argptr, double));
3594 break;
3596 case 's':
3597 *q++ = c;
3598 *q = 0;
3599 fprintf (file, buf, va_arg (argptr, char *));
3600 break;
3602 case 'O':
3603 #ifdef ASM_OUTPUT_OPCODE
3604 ASM_OUTPUT_OPCODE (asm_out_file, p);
3605 #endif
3606 break;
3608 case 'R':
3609 #ifdef REGISTER_PREFIX
3610 fprintf (file, "%s", REGISTER_PREFIX);
3611 #endif
3612 break;
3614 case 'I':
3615 #ifdef IMMEDIATE_PREFIX
3616 fprintf (file, "%s", IMMEDIATE_PREFIX);
3617 #endif
3618 break;
3620 case 'L':
3621 #ifdef LOCAL_LABEL_PREFIX
3622 fprintf (file, "%s", LOCAL_LABEL_PREFIX);
3623 #endif
3624 break;
3626 case 'U':
3627 fputs (user_label_prefix, file);
3628 break;
3630 #ifdef ASM_FPRINTF_EXTENSIONS
3631 /* Upper case letters are reserved for general use by asm_fprintf
3632 and so are not available to target specific code. In order to
3633 prevent the ASM_FPRINTF_EXTENSIONS macro from using them then,
3634 they are defined here. As they get turned into real extensions
3635 to asm_fprintf they should be removed from this list. */
3636 case 'A': case 'B': case 'C': case 'D': case 'E':
3637 case 'F': case 'G': case 'H': case 'J': case 'K':
3638 case 'M': case 'N': case 'P': case 'Q': case 'S':
3639 case 'T': case 'V': case 'W': case 'Y': case 'Z':
3640 break;
3642 ASM_FPRINTF_EXTENSIONS (file, argptr, p)
3643 #endif
3644 default:
3645 abort ();
3647 break;
3649 default:
3650 fputc (c, file);
3652 VA_CLOSE (argptr);
3655 /* Split up a CONST_DOUBLE or integer constant rtx
3656 into two rtx's for single words,
3657 storing in *FIRST the word that comes first in memory in the target
3658 and in *SECOND the other. */
3660 void
3661 split_double (value, first, second)
3662 rtx value;
3663 rtx *first, *second;
3665 if (GET_CODE (value) == CONST_INT)
3667 if (HOST_BITS_PER_WIDE_INT >= (2 * BITS_PER_WORD))
3669 /* In this case the CONST_INT holds both target words.
3670 Extract the bits from it into two word-sized pieces.
3671 Sign extend each half to HOST_WIDE_INT. */
3672 unsigned HOST_WIDE_INT low, high;
3673 unsigned HOST_WIDE_INT mask, sign_bit, sign_extend;
3675 /* Set sign_bit to the most significant bit of a word. */
3676 sign_bit = 1;
3677 sign_bit <<= BITS_PER_WORD - 1;
3679 /* Set mask so that all bits of the word are set. We could
3680 have used 1 << BITS_PER_WORD instead of basing the
3681 calculation on sign_bit. However, on machines where
3682 HOST_BITS_PER_WIDE_INT == BITS_PER_WORD, it could cause a
3683 compiler warning, even though the code would never be
3684 executed. */
3685 mask = sign_bit << 1;
3686 mask--;
3688 /* Set sign_extend as any remaining bits. */
3689 sign_extend = ~mask;
3691 /* Pick the lower word and sign-extend it. */
3692 low = INTVAL (value);
3693 low &= mask;
3694 if (low & sign_bit)
3695 low |= sign_extend;
3697 /* Pick the higher word, shifted to the least significant
3698 bits, and sign-extend it. */
3699 high = INTVAL (value);
3700 high >>= BITS_PER_WORD - 1;
3701 high >>= 1;
3702 high &= mask;
3703 if (high & sign_bit)
3704 high |= sign_extend;
3706 /* Store the words in the target machine order. */
3707 if (WORDS_BIG_ENDIAN)
3709 *first = GEN_INT (high);
3710 *second = GEN_INT (low);
3712 else
3714 *first = GEN_INT (low);
3715 *second = GEN_INT (high);
3718 else
3720 /* The rule for using CONST_INT for a wider mode
3721 is that we regard the value as signed.
3722 So sign-extend it. */
3723 rtx high = (INTVAL (value) < 0 ? constm1_rtx : const0_rtx);
3724 if (WORDS_BIG_ENDIAN)
3726 *first = high;
3727 *second = value;
3729 else
3731 *first = value;
3732 *second = high;
3736 else if (GET_CODE (value) != CONST_DOUBLE)
3738 if (WORDS_BIG_ENDIAN)
3740 *first = const0_rtx;
3741 *second = value;
3743 else
3745 *first = value;
3746 *second = const0_rtx;
3749 else if (GET_MODE (value) == VOIDmode
3750 /* This is the old way we did CONST_DOUBLE integers. */
3751 || GET_MODE_CLASS (GET_MODE (value)) == MODE_INT)
3753 /* In an integer, the words are defined as most and least significant.
3754 So order them by the target's convention. */
3755 if (WORDS_BIG_ENDIAN)
3757 *first = GEN_INT (CONST_DOUBLE_HIGH (value));
3758 *second = GEN_INT (CONST_DOUBLE_LOW (value));
3760 else
3762 *first = GEN_INT (CONST_DOUBLE_LOW (value));
3763 *second = GEN_INT (CONST_DOUBLE_HIGH (value));
3766 else
3768 REAL_VALUE_TYPE r;
3769 long l[2];
3770 REAL_VALUE_FROM_CONST_DOUBLE (r, value);
3772 /* Note, this converts the REAL_VALUE_TYPE to the target's
3773 format, splits up the floating point double and outputs
3774 exactly 32 bits of it into each of l[0] and l[1] --
3775 not necessarily BITS_PER_WORD bits. */
3776 REAL_VALUE_TO_TARGET_DOUBLE (r, l);
3778 /* If 32 bits is an entire word for the target, but not for the host,
3779 then sign-extend on the host so that the number will look the same
3780 way on the host that it would on the target. See for instance
3781 simplify_unary_operation. The #if is needed to avoid compiler
3782 warnings. */
3784 #if HOST_BITS_PER_LONG > 32
3785 if (BITS_PER_WORD < HOST_BITS_PER_LONG && BITS_PER_WORD == 32)
3787 if (l[0] & ((long) 1 << 31))
3788 l[0] |= ((long) (-1) << 32);
3789 if (l[1] & ((long) 1 << 31))
3790 l[1] |= ((long) (-1) << 32);
3792 #endif
3794 *first = GEN_INT ((HOST_WIDE_INT) l[0]);
3795 *second = GEN_INT ((HOST_WIDE_INT) l[1]);
3799 /* Return nonzero if this function has no function calls. */
3802 leaf_function_p ()
3804 rtx insn;
3805 rtx link;
3807 if (current_function_profile || profile_arc_flag)
3808 return 0;
3810 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3812 if (GET_CODE (insn) == CALL_INSN
3813 && ! SIBLING_CALL_P (insn))
3814 return 0;
3815 if (GET_CODE (insn) == INSN
3816 && GET_CODE (PATTERN (insn)) == SEQUENCE
3817 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == CALL_INSN
3818 && ! SIBLING_CALL_P (XVECEXP (PATTERN (insn), 0, 0)))
3819 return 0;
3821 for (link = current_function_epilogue_delay_list;
3822 link;
3823 link = XEXP (link, 1))
3825 insn = XEXP (link, 0);
3827 if (GET_CODE (insn) == CALL_INSN
3828 && ! SIBLING_CALL_P (insn))
3829 return 0;
3830 if (GET_CODE (insn) == INSN
3831 && GET_CODE (PATTERN (insn)) == SEQUENCE
3832 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == CALL_INSN
3833 && ! SIBLING_CALL_P (XVECEXP (PATTERN (insn), 0, 0)))
3834 return 0;
3837 return 1;
3840 /* Return 1 if branch is an forward branch.
3841 Uses insn_shuid array, so it works only in the final pass. May be used by
3842 output templates to customary add branch prediction hints.
3845 final_forward_branch_p (insn)
3846 rtx insn;
3848 int insn_id, label_id;
3849 if (!uid_shuid)
3850 abort ();
3851 insn_id = INSN_SHUID (insn);
3852 label_id = INSN_SHUID (JUMP_LABEL (insn));
3853 /* We've hit some insns that does not have id information available. */
3854 if (!insn_id || !label_id)
3855 abort ();
3856 return insn_id < label_id;
3859 /* On some machines, a function with no call insns
3860 can run faster if it doesn't create its own register window.
3861 When output, the leaf function should use only the "output"
3862 registers. Ordinarily, the function would be compiled to use
3863 the "input" registers to find its arguments; it is a candidate
3864 for leaf treatment if it uses only the "input" registers.
3865 Leaf function treatment means renumbering so the function
3866 uses the "output" registers instead. */
3868 #ifdef LEAF_REGISTERS
3870 /* Return 1 if this function uses only the registers that can be
3871 safely renumbered. */
3874 only_leaf_regs_used ()
3876 int i;
3877 char *permitted_reg_in_leaf_functions = LEAF_REGISTERS;
3879 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
3880 if ((regs_ever_live[i] || global_regs[i])
3881 && ! permitted_reg_in_leaf_functions[i])
3882 return 0;
3884 if (current_function_uses_pic_offset_table
3885 && pic_offset_table_rtx != 0
3886 && GET_CODE (pic_offset_table_rtx) == REG
3887 && ! permitted_reg_in_leaf_functions[REGNO (pic_offset_table_rtx)])
3888 return 0;
3890 return 1;
3893 /* Scan all instructions and renumber all registers into those
3894 available in leaf functions. */
3896 static void
3897 leaf_renumber_regs (first)
3898 rtx first;
3900 rtx insn;
3902 /* Renumber only the actual patterns.
3903 The reg-notes can contain frame pointer refs,
3904 and renumbering them could crash, and should not be needed. */
3905 for (insn = first; insn; insn = NEXT_INSN (insn))
3906 if (INSN_P (insn))
3907 leaf_renumber_regs_insn (PATTERN (insn));
3908 for (insn = current_function_epilogue_delay_list;
3909 insn;
3910 insn = XEXP (insn, 1))
3911 if (INSN_P (XEXP (insn, 0)))
3912 leaf_renumber_regs_insn (PATTERN (XEXP (insn, 0)));
3915 /* Scan IN_RTX and its subexpressions, and renumber all regs into those
3916 available in leaf functions. */
3918 void
3919 leaf_renumber_regs_insn (in_rtx)
3920 rtx in_rtx;
3922 int i, j;
3923 const char *format_ptr;
3925 if (in_rtx == 0)
3926 return;
3928 /* Renumber all input-registers into output-registers.
3929 renumbered_regs would be 1 for an output-register;
3930 they */
3932 if (GET_CODE (in_rtx) == REG)
3934 int newreg;
3936 /* Don't renumber the same reg twice. */
3937 if (in_rtx->used)
3938 return;
3940 newreg = REGNO (in_rtx);
3941 /* Don't try to renumber pseudo regs. It is possible for a pseudo reg
3942 to reach here as part of a REG_NOTE. */
3943 if (newreg >= FIRST_PSEUDO_REGISTER)
3945 in_rtx->used = 1;
3946 return;
3948 newreg = LEAF_REG_REMAP (newreg);
3949 if (newreg < 0)
3950 abort ();
3951 regs_ever_live[REGNO (in_rtx)] = 0;
3952 regs_ever_live[newreg] = 1;
3953 REGNO (in_rtx) = newreg;
3954 in_rtx->used = 1;
3957 if (INSN_P (in_rtx))
3959 /* Inside a SEQUENCE, we find insns.
3960 Renumber just the patterns of these insns,
3961 just as we do for the top-level insns. */
3962 leaf_renumber_regs_insn (PATTERN (in_rtx));
3963 return;
3966 format_ptr = GET_RTX_FORMAT (GET_CODE (in_rtx));
3968 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (in_rtx)); i++)
3969 switch (*format_ptr++)
3971 case 'e':
3972 leaf_renumber_regs_insn (XEXP (in_rtx, i));
3973 break;
3975 case 'E':
3976 if (NULL != XVEC (in_rtx, i))
3978 for (j = 0; j < XVECLEN (in_rtx, i); j++)
3979 leaf_renumber_regs_insn (XVECEXP (in_rtx, i, j));
3981 break;
3983 case 'S':
3984 case 's':
3985 case '0':
3986 case 'i':
3987 case 'w':
3988 case 'n':
3989 case 'u':
3990 break;
3992 default:
3993 abort ();
3996 #endif