aboutsummaryrefslogtreecommitdiffstats
path: root/gcc-4.9/gcc/rtl.def
blob: 56418c792e053dcdef3f804d7044af1fa0dc72f8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
/* This file contains the definitions and documentation for the
   Register Transfer Expressions (rtx's) that make up the
   Register Transfer Language (rtl) used in the Back End of the GNU compiler.
   Copyright (C) 1987-2014 Free Software Foundation, Inc.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */


/* Expression definitions and descriptions for all targets are in this file.
   Some will not be used for some targets.

   The fields in the cpp macro call "DEF_RTL_EXPR()"
   are used to create declarations in the C source of the compiler.

   The fields are:

   1.  The internal name of the rtx used in the C source.
   It is a tag in the enumeration "enum rtx_code" defined in "rtl.h".
   By convention these are in UPPER_CASE.

   2.  The name of the rtx in the external ASCII format read by
   read_rtx(), and printed by print_rtx().
   These names are stored in rtx_name[].
   By convention these are the internal (field 1) names in lower_case.

   3.  The print format, and type of each rtx->u.fld[] (field) in this rtx.
   These formats are stored in rtx_format[].
   The meaning of the formats is documented in front of this array in rtl.c

   4.  The class of the rtx.  These are stored in rtx_class and are accessed
   via the GET_RTX_CLASS macro.  They are defined as follows:

     RTX_CONST_OBJ
         an rtx code that can be used to represent a constant object
         (e.g, CONST_INT)
     RTX_OBJ
         an rtx code that can be used to represent an object (e.g, REG, MEM)
     RTX_COMPARE
         an rtx code for a comparison (e.g, LT, GT)
     RTX_COMM_COMPARE
         an rtx code for a commutative comparison (e.g, EQ, NE, ORDERED)
     RTX_UNARY
         an rtx code for a unary arithmetic expression (e.g, NEG, NOT)
     RTX_COMM_ARITH
         an rtx code for a commutative binary operation (e.g,, PLUS, MULT)
     RTX_TERNARY
         an rtx code for a non-bitfield three input operation (IF_THEN_ELSE)
     RTX_BIN_ARITH
         an rtx code for a non-commutative binary operation (e.g., MINUS, DIV)
     RTX_BITFIELD_OPS
         an rtx code for a bit-field operation (ZERO_EXTRACT, SIGN_EXTRACT)
     RTX_INSN
         an rtx code for a machine insn (INSN, JUMP_INSN, CALL_INSN) or
	 data that will be output as assembly pseudo-ops (DEBUG_INSN)
     RTX_MATCH
         an rtx code for something that matches in insns (e.g, MATCH_DUP)
     RTX_AUTOINC
         an rtx code for autoincrement addressing modes (e.g. POST_DEC)
     RTX_EXTRA
         everything else

   All of the expressions that appear only in machine descriptions,
   not in RTL used by the compiler itself, are at the end of the file.  */

/* Unknown, or no such operation; the enumeration constant should have
   value zero.  */
DEF_RTL_EXPR(UNKNOWN, "UnKnown", "*", RTX_EXTRA)

/* Used in the cselib routines to describe a value.  Objects of this
   kind are only allocated in cselib.c, in an alloc pool instead of in
   GC memory.  The only operand of a VALUE is a cselib_val.
   var-tracking requires this to have a distinct integral value from
   DECL codes in trees.  */
DEF_RTL_EXPR(VALUE, "value", "0", RTX_OBJ)

/* The RTL generated for a DEBUG_EXPR_DECL.  It links back to the
   DEBUG_EXPR_DECL in the first operand.  */
DEF_RTL_EXPR(DEBUG_EXPR, "debug_expr", "0", RTX_OBJ)

/* ---------------------------------------------------------------------
   Expressions used in constructing lists.
   --------------------------------------------------------------------- */

/* A linked list of expressions.  */
DEF_RTL_EXPR(EXPR_LIST, "expr_list", "ee", RTX_EXTRA)

/* A linked list of instructions.
   The insns are represented in print by their uids.  */
DEF_RTL_EXPR(INSN_LIST, "insn_list", "ue", RTX_EXTRA)

/* A linked list of integers.  */
DEF_RTL_EXPR(INT_LIST, "int_list", "ie", RTX_EXTRA)

/* SEQUENCE is used in late passes of the compiler to group insns for
   one reason or another.

   For example, after delay slot filling, branch instructions with filled
   delay slots are represented as a SEQUENCE of length 1 + n_delay_slots,
   with the branch instruction in XEXPVEC(seq, 0, 0) and the instructions
   occupying the delay slots in the remaining XEXPVEC slots.

   Another place where a SEQUENCE may appear, is in REG_FRAME_RELATED_EXPR
   notes, to express complex operations that are not obvious from the insn
   to which the REG_FRAME_RELATED_EXPR note is attached.  In this usage of
   SEQUENCE, the sequence vector slots do not hold real instructions but
   only pseudo-instructions that can be translated to DWARF CFA expressions.

   Some back ends also use SEQUENCE to group insns in bundles.

   Much of the compiler infrastructure is not prepared to handle SEQUENCE
   objects.  Only passes after pass_free_cfg are expected to handle them.  */
DEF_RTL_EXPR(SEQUENCE, "sequence", "E", RTX_EXTRA)

/* Represents a non-global base address.  This is only used in alias.c.  */
DEF_RTL_EXPR(ADDRESS, "address", "i", RTX_EXTRA)

/* ----------------------------------------------------------------------
   Expression types used for things in the instruction chain.

   All formats must start with "iuu" to handle the chain.
   Each insn expression holds an rtl instruction and its semantics
   during back-end processing.
   See macros's in "rtl.h" for the meaning of each rtx->u.fld[].

   ---------------------------------------------------------------------- */

/* An annotation for variable assignment tracking.  */
DEF_RTL_EXPR(DEBUG_INSN, "debug_insn", "iuuBeiie", RTX_INSN)

/* An instruction that cannot jump.  */
DEF_RTL_EXPR(INSN, "insn", "iuuBeiie", RTX_INSN)

/* An instruction that can possibly jump.
   Fields ( rtx->u.fld[] ) have exact same meaning as INSN's.  */
DEF_RTL_EXPR(JUMP_INSN, "jump_insn", "iuuBeiie0", RTX_INSN)

/* An instruction that can possibly call a subroutine
   but which will not change which instruction comes next
   in the current function.
   Field ( rtx->u.fld[8] ) is CALL_INSN_FUNCTION_USAGE.
   All other fields ( rtx->u.fld[] ) have exact same meaning as INSN's.  */
DEF_RTL_EXPR(CALL_INSN, "call_insn", "iuuBeiiee", RTX_INSN)

/* Placeholder for tablejump JUMP_INSNs.  The pattern of this kind
   of rtx is always either an ADDR_VEC or an ADDR_DIFF_VEC.  These
   placeholders do not appear as real instructions inside a basic
   block, but are considered active_insn_p instructions for historical
   reasons, when jump table data was represented with JUMP_INSNs.  */
DEF_RTL_EXPR(JUMP_TABLE_DATA, "jump_table_data", "iuuBe0000", RTX_INSN)

/* A marker that indicates that control will not flow through.  */
DEF_RTL_EXPR(BARRIER, "barrier", "iuu00000", RTX_EXTRA)

/* Holds a label that is followed by instructions.
   Operand:
   4: is used in jump.c for the use-count of the label.
   5: is used in the sh backend.
   6: is a number that is unique in the entire compilation.
   7: is the user-given name of the label, if any.  */
DEF_RTL_EXPR(CODE_LABEL, "code_label", "iuuB00is", RTX_EXTRA)

/* Say where in the code a source line starts, for symbol table's sake.
   Operand:
   4: note-specific data
   5: enum insn_note
   6: unique number if insn_note == note_insn_deleted_label.  */
DEF_RTL_EXPR(NOTE, "note", "iuuB0ni", RTX_EXTRA)

/* ----------------------------------------------------------------------
   Top level constituents of INSN, JUMP_INSN and CALL_INSN.
   ---------------------------------------------------------------------- */

/* Conditionally execute code.
   Operand 0 is the condition that if true, the code is executed.
   Operand 1 is the code to be executed (typically a SET).

   Semantics are that there are no side effects if the condition
   is false.  This pattern is created automatically by the if_convert
   pass run after reload or by target-specific splitters.  */
DEF_RTL_EXPR(COND_EXEC, "cond_exec", "ee", RTX_EXTRA)

/* Several operations to be done in parallel (perhaps under COND_EXEC).  */
DEF_RTL_EXPR(PARALLEL, "parallel", "E", RTX_EXTRA)

/* A string that is passed through to the assembler as input.
     One can obviously pass comments through by using the
     assembler comment syntax.
     These occur in an insn all by themselves as the PATTERN.
     They also appear inside an ASM_OPERANDS
     as a convenient way to hold a string.  */
DEF_RTL_EXPR(ASM_INPUT, "asm_input", "si", RTX_EXTRA)

/* An assembler instruction with operands.
   1st operand is the instruction template.
   2nd operand is the constraint for the output.
   3rd operand is the number of the output this expression refers to.
     When an insn stores more than one value, a separate ASM_OPERANDS
     is made for each output; this integer distinguishes them.
   4th is a vector of values of input operands.
   5th is a vector of modes and constraints for the input operands.
     Each element is an ASM_INPUT containing a constraint string
     and whose mode indicates the mode of the input operand.
   6th is a vector of labels that may be branched to by the asm.
   7th is the source line number.  */
DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEEi", RTX_EXTRA)

/* A machine-specific operation.
   1st operand is a vector of operands being used by the operation so that
     any needed reloads can be done.
   2nd operand is a unique value saying which of a number of machine-specific
     operations is to be performed.
   (Note that the vector must be the first operand because of the way that
   genrecog.c record positions within an insn.)

   UNSPEC can occur all by itself in a PATTERN, as a component of a PARALLEL,
   or inside an expression.
   UNSPEC by itself or as a component of a PARALLEL
   is currently considered not deletable.

   FIXME: Replace all uses of UNSPEC that appears by itself or as a component
   of a PARALLEL with USE.
   */
DEF_RTL_EXPR(UNSPEC, "unspec", "Ei", RTX_EXTRA)

/* Similar, but a volatile operation and one which may trap.  */
DEF_RTL_EXPR(UNSPEC_VOLATILE, "unspec_volatile", "Ei", RTX_EXTRA)

/* ----------------------------------------------------------------------
   Table jump addresses.
   ---------------------------------------------------------------------- */

/* Vector of addresses, stored as full words.
   Each element is a LABEL_REF to a CODE_LABEL whose address we want.  */
DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", RTX_EXTRA)

/* Vector of address differences X0 - BASE, X1 - BASE, ...
   First operand is BASE; the vector contains the X's.
   The machine mode of this rtx says how much space to leave
   for each difference and is adjusted by branch shortening if
   CASE_VECTOR_SHORTEN_MODE is defined.
   The third and fourth operands store the target labels with the
   minimum and maximum addresses respectively.
   The fifth operand stores flags for use by branch shortening.
  Set at the start of shorten_branches:
   min_align: the minimum alignment for any of the target labels.
   base_after_vec: true iff BASE is after the ADDR_DIFF_VEC.
   min_after_vec: true iff minimum addr target label is after the ADDR_DIFF_VEC.
   max_after_vec: true iff maximum addr target label is after the ADDR_DIFF_VEC.
   min_after_base: true iff minimum address target label is after BASE.
   max_after_base: true iff maximum address target label is after BASE.
  Set by the actual branch shortening process:
   offset_unsigned: true iff offsets have to be treated as unsigned.
   scale: scaling that is necessary to make offsets fit into the mode.

   The third, fourth and fifth operands are only valid when
   CASE_VECTOR_SHORTEN_MODE is defined, and only in an optimizing
   compilation.  */
DEF_RTL_EXPR(ADDR_DIFF_VEC, "addr_diff_vec", "eEee0", RTX_EXTRA)

/* Memory prefetch, with attributes supported on some targets.
   Operand 1 is the address of the memory to fetch.
   Operand 2 is 1 for a write access, 0 otherwise.
   Operand 3 is the level of temporal locality; 0 means there is no
   temporal locality and 1, 2, and 3 are for increasing levels of temporal
   locality.

   The attributes specified by operands 2 and 3 are ignored for targets
   whose prefetch instructions do not support them.  */
DEF_RTL_EXPR(PREFETCH, "prefetch", "eee", RTX_EXTRA)

/* ----------------------------------------------------------------------
   At the top level of an instruction (perhaps under PARALLEL).
   ---------------------------------------------------------------------- */

/* Assignment.
   Operand 1 is the location (REG, MEM, PC, CC0 or whatever) assigned to.
   Operand 2 is the value stored there.
   ALL assignment must use SET.
   Instructions that do multiple assignments must use multiple SET,
   under PARALLEL.  */
DEF_RTL_EXPR(SET, "set", "ee", RTX_EXTRA)

/* Indicate something is used in a way that we don't want to explain.
   For example, subroutine calls will use the register
   in which the static chain is passed.

   USE can not appear as an operand of other rtx except for PARALLEL.
   USE is not deletable, as it indicates that the operand
   is used in some unknown way.  */
DEF_RTL_EXPR(USE, "use", "e", RTX_EXTRA)

/* Indicate something is clobbered in a way that we don't want to explain.
   For example, subroutine calls will clobber some physical registers
   (the ones that are by convention not saved).

   CLOBBER can not appear as an operand of other rtx except for PARALLEL.
   CLOBBER of a hard register appearing by itself (not within PARALLEL)
   is considered undeletable before reload.  */
DEF_RTL_EXPR(CLOBBER, "clobber", "e", RTX_EXTRA)

/* Call a subroutine.
   Operand 1 is the address to call.
   Operand 2 is the number of arguments.  */

DEF_RTL_EXPR(CALL, "call", "ee", RTX_EXTRA)

/* Return from a subroutine.  */

DEF_RTL_EXPR(RETURN, "return", "", RTX_EXTRA)

/* Like RETURN, but truly represents only a function return, while
   RETURN may represent an insn that also performs other functions
   of the function epilogue.  Like RETURN, this may also occur in
   conditional jumps.  */
DEF_RTL_EXPR(SIMPLE_RETURN, "simple_return", "", RTX_EXTRA)

/* Special for EH return from subroutine.  */

DEF_RTL_EXPR(EH_RETURN, "eh_return", "", RTX_EXTRA)

/* Conditional trap.
   Operand 1 is the condition.
   Operand 2 is the trap code.
   For an unconditional trap, make the condition (const_int 1).  */
DEF_RTL_EXPR(TRAP_IF, "trap_if", "ee", RTX_EXTRA)

/* ----------------------------------------------------------------------
   Primitive values for use in expressions.
   ---------------------------------------------------------------------- */

/* numeric integer constant */
DEF_RTL_EXPR(CONST_INT, "const_int", "w", RTX_CONST_OBJ)

/* fixed-point constant */
DEF_RTL_EXPR(CONST_FIXED, "const_fixed", "www", RTX_CONST_OBJ)

/* numeric floating point or integer constant.  If the mode is
   VOIDmode it is an int otherwise it has a floating point mode and a
   floating point value.  Operands hold the value.  They are all 'w'
   and there may be from 2 to 6; see real.h.  */
DEF_RTL_EXPR(CONST_DOUBLE, "const_double", CONST_DOUBLE_FORMAT, RTX_CONST_OBJ)

/* Describes a vector constant.  */
DEF_RTL_EXPR(CONST_VECTOR, "const_vector", "E", RTX_CONST_OBJ)

/* String constant.  Used for attributes in machine descriptions and
   for special cases in DWARF2 debug output.  NOT used for source-
   language string constants.  */
DEF_RTL_EXPR(CONST_STRING, "const_string", "s", RTX_OBJ)

/* This is used to encapsulate an expression whose value is constant
   (such as the sum of a SYMBOL_REF and a CONST_INT) so that it will be
   recognized as a constant operand rather than by arithmetic instructions.  */

DEF_RTL_EXPR(CONST, "const", "e", RTX_CONST_OBJ)

/* program counter.  Ordinary jumps are represented
   by a SET whose first operand is (PC).  */
DEF_RTL_EXPR(PC, "pc", "", RTX_OBJ)

/* A register.  The "operand" is the register number, accessed with
   the REGNO macro.  If this number is less than FIRST_PSEUDO_REGISTER
   than a hardware register is being referred to.  The second operand
   holds the original register number - this will be different for a
   pseudo register that got turned into a hard register.  The third
   operand points to a reg_attrs structure.
   This rtx needs to have as many (or more) fields as a MEM, since we
   can change REG rtx's into MEMs during reload.  */
DEF_RTL_EXPR(REG, "reg", "i00", RTX_OBJ)

/* A scratch register.  This represents a register used only within a
   single insn.  It will be turned into a REG during register allocation
   or reload unless the constraint indicates that the register won't be
   needed, in which case it can remain a SCRATCH.  This code is
   marked as having one operand so it can be turned into a REG.  */
DEF_RTL_EXPR(SCRATCH, "scratch", "0", RTX_OBJ)

/* A reference to a part of another value.  The first operand is the
   complete value and the second is the byte offset of the selected part.   */
DEF_RTL_EXPR(SUBREG, "subreg", "ei", RTX_EXTRA)

/* This one-argument rtx is used for move instructions
   that are guaranteed to alter only the low part of a destination.
   Thus, (SET (SUBREG:HI (REG...)) (MEM:HI ...))
   has an unspecified effect on the high part of REG,
   but (SET (STRICT_LOW_PART (SUBREG:HI (REG...))) (MEM:HI ...))
   is guaranteed to alter only the bits of REG that are in HImode.

   The actual instruction used is probably the same in both cases,
   but the register constraints may be tighter when STRICT_LOW_PART
   is in use.  */

DEF_RTL_EXPR(STRICT_LOW_PART, "strict_low_part", "e", RTX_EXTRA)

/* (CONCAT a b) represents the virtual concatenation of a and b
   to make a value that has as many bits as a and b put together.
   This is used for complex values.  Normally it appears only
   in DECL_RTLs and during RTL generation, but not in the insn chain.  */
DEF_RTL_EXPR(CONCAT, "concat", "ee", RTX_OBJ)

/* (CONCATN [a1 a2 ... an]) represents the virtual concatenation of
   all An to make a value.  This is an extension of CONCAT to larger
   number of components.  Like CONCAT, it should not appear in the
   insn chain.  Every element of the CONCATN is the same size.  */
DEF_RTL_EXPR(CONCATN, "concatn", "E", RTX_OBJ)

/* A memory location; operand is the address.  The second operand is the
   alias set to which this MEM belongs.  We use `0' instead of `w' for this
   field so that the field need not be specified in machine descriptions.  */
DEF_RTL_EXPR(MEM, "mem", "e0", RTX_OBJ)

/* Reference to an assembler label in the code for this function.
   The operand is a CODE_LABEL found in the insn chain.  */
DEF_RTL_EXPR(LABEL_REF, "label_ref", "u", RTX_CONST_OBJ)

/* Reference to a named label:
   Operand 0: label name
   Operand 1: flags (see SYMBOL_FLAG_* in rtl.h)
   Operand 2: tree from which this symbol is derived, or null.
   This is either a DECL node, or some kind of constant.  */
DEF_RTL_EXPR(SYMBOL_REF, "symbol_ref", "s00", RTX_CONST_OBJ)

/* The condition code register is represented, in our imagination,
   as a register holding a value that can be compared to zero.
   In fact, the machine has already compared them and recorded the
   results; but instructions that look at the condition code
   pretend to be looking at the entire value and comparing it.  */
DEF_RTL_EXPR(CC0, "cc0", "", RTX_OBJ)

/* ----------------------------------------------------------------------
   Expressions for operators in an rtl pattern
   ---------------------------------------------------------------------- */

/* if_then_else.  This is used in representing ordinary
   conditional jump instructions.
     Operand:
     0:  condition
     1:  then expr
     2:  else expr */
DEF_RTL_EXPR(IF_THEN_ELSE, "if_then_else", "eee", RTX_TERNARY)

/* Comparison, produces a condition code result.  */
DEF_RTL_EXPR(COMPARE, "compare", "ee", RTX_BIN_ARITH)

/* plus */
DEF_RTL_EXPR(PLUS, "plus", "ee", RTX_COMM_ARITH)

/* Operand 0 minus operand 1.  */
DEF_RTL_EXPR(MINUS, "minus", "ee", RTX_BIN_ARITH)

/* Minus operand 0.  */
DEF_RTL_EXPR(NEG, "neg", "e", RTX_UNARY)

DEF_RTL_EXPR(MULT, "mult", "ee", RTX_COMM_ARITH)

/* Multiplication with signed saturation */
DEF_RTL_EXPR(SS_MULT, "ss_mult", "ee", RTX_COMM_ARITH)
/* Multiplication with unsigned saturation */
DEF_RTL_EXPR(US_MULT, "us_mult", "ee", RTX_COMM_ARITH)

/* Operand 0 divided by operand 1.  */
DEF_RTL_EXPR(DIV, "div", "ee", RTX_BIN_ARITH)
/* Division with signed saturation */
DEF_RTL_EXPR(SS_DIV, "ss_div", "ee", RTX_BIN_ARITH)
/* Division with unsigned saturation */
DEF_RTL_EXPR(US_DIV, "us_div", "ee", RTX_BIN_ARITH)

/* Remainder of operand 0 divided by operand 1.  */
DEF_RTL_EXPR(MOD, "mod", "ee", RTX_BIN_ARITH)

/* Unsigned divide and remainder.  */
DEF_RTL_EXPR(UDIV, "udiv", "ee", RTX_BIN_ARITH)
DEF_RTL_EXPR(UMOD, "umod", "ee", RTX_BIN_ARITH)

/* Bitwise operations.  */
DEF_RTL_EXPR(AND, "and", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(IOR, "ior", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(XOR, "xor", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(NOT, "not", "e", RTX_UNARY)

/* Operand:
     0:  value to be shifted.
     1:  number of bits.  */
DEF_RTL_EXPR(ASHIFT, "ashift", "ee", RTX_BIN_ARITH) /* shift left */
DEF_RTL_EXPR(ROTATE, "rotate", "ee", RTX_BIN_ARITH) /* rotate left */
DEF_RTL_EXPR(ASHIFTRT, "ashiftrt", "ee", RTX_BIN_ARITH) /* arithmetic shift right */
DEF_RTL_EXPR(LSHIFTRT, "lshiftrt", "ee", RTX_BIN_ARITH) /* logical shift right */
DEF_RTL_EXPR(ROTATERT, "rotatert", "ee", RTX_BIN_ARITH) /* rotate right */

/* Minimum and maximum values of two operands.  We need both signed and
   unsigned forms.  (We cannot use MIN for SMIN because it conflicts
   with a macro of the same name.)   The signed variants should be used
   with floating point.  Further, if both operands are zeros, or if either
   operand is NaN, then it is unspecified which of the two operands is
   returned as the result.  */

DEF_RTL_EXPR(SMIN, "smin", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(SMAX, "smax", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(UMIN, "umin", "ee", RTX_COMM_ARITH)
DEF_RTL_EXPR(UMAX, "umax", "ee", RTX_COMM_ARITH)

/* These unary operations are used to represent incrementation
   and decrementation as they occur in memory addresses.
   The amount of increment or decrement are not represented
   because they can be understood from the machine-mode of the
   containing MEM.  These operations exist in only two cases:
   1. pushes onto the stack.
   2. created automatically by the auto-inc-dec pass.  */
DEF_RTL_EXPR(PRE_DEC, "pre_dec", "e", RTX_AUTOINC)
DEF_RTL_EXPR(PRE_INC, "pre_inc", "e", RTX_AUTOINC)
DEF_RTL_EXPR(POST_DEC, "post_dec", "e", RTX_AUTOINC)
DEF_RTL_EXPR(POST_INC, "post_inc", "e", RTX_AUTOINC)

/* These binary operations are used to represent generic address
   side-effects in memory addresses, except for simple incrementation
   or decrementation which use the above operations.  They are
   created automatically by the life_analysis pass in flow.c.
   The first operand is a REG which is used as the address.
   The second operand is an expression that is assigned to the
   register, either before (PRE_MODIFY) or after (POST_MODIFY)
   evaluating the address.
   Currently, the compiler can only handle second operands of the
   form (plus (reg) (reg)) and (plus (reg) (const_int)), where
   the first operand of the PLUS has to be the same register as
   the first operand of the *_MODIFY.  */
DEF_RTL_EXPR(PRE_MODIFY, "pre_modify", "ee", RTX_AUTOINC)
DEF_RTL_EXPR(POST_MODIFY, "post_modify", "ee", RTX_AUTOINC)

/* Comparison operations.  The ordered comparisons exist in two
   flavors, signed and unsigned.  */
DEF_RTL_EXPR(NE, "ne", "ee", RTX_COMM_COMPARE)
DEF_RTL_EXPR(EQ, "eq", "ee", RTX_COMM_COMPARE)
DEF_RTL_EXPR(GE, "ge", "ee", RTX_COMPARE)
DEF_RTL_EXPR(GT, "gt", "ee", RTX_COMPARE)
DEF_RTL_EXPR(LE, "le", "ee", RTX_COMPARE)
DEF_RTL_EXPR(LT, "lt", "ee", RTX_COMPARE)
DEF_RTL_EXPR(GEU, "geu", "ee", RTX_COMPARE)
DEF_RTL_EXPR(GTU, "gtu", "ee", RTX_COMPARE)
DEF_RTL_EXPR(LEU, "leu", "ee", RTX_COMPARE)
DEF_RTL_EXPR(LTU, "ltu", "ee", RTX_COMPARE)

/* Additional floating point unordered comparison flavors.  */
DEF_RTL_EXPR(UNORDERED, "unordered", "ee", RTX_COMM_COMPARE)
DEF_RTL_EXPR(ORDERED, "ordered", "ee", RTX_COMM_COMPARE)

/* These are equivalent to unordered or ...  */
DEF_RTL_EXPR(UNEQ, "uneq", "ee", RTX_COMM_COMPARE)
DEF_RTL_EXPR(UNGE, "unge", "ee", RTX_COMPARE)
DEF_RTL_EXPR(UNGT, "ungt", "ee", RTX_COMPARE)
DEF_RTL_EXPR(UNLE, "unle", "ee", RTX_COMPARE)
DEF_RTL_EXPR(UNLT, "unlt", "ee", RTX_COMPARE)

/* This is an ordered NE, ie !UNEQ, ie false for NaN.  */
DEF_RTL_EXPR(LTGT, "ltgt", "ee", RTX_COMM_COMPARE)

/* Represents the result of sign-extending the sole operand.
   The machine modes of the operand and of the SIGN_EXTEND expression
   determine how much sign-extension is going on.  */
DEF_RTL_EXPR(SIGN_EXTEND, "sign_extend", "e", RTX_UNARY)

/* Similar for zero-extension (such as unsigned short to int).  */
DEF_RTL_EXPR(ZERO_EXTEND, "zero_extend", "e", RTX_UNARY)

/* Similar but here the operand has a wider mode.  */
DEF_RTL_EXPR(TRUNCATE, "truncate", "e", RTX_UNARY)

/* Similar for extending floating-point values (such as SFmode to DFmode).  */
DEF_RTL_EXPR(FLOAT_EXTEND, "float_extend", "e", RTX_UNARY)
DEF_RTL_EXPR(FLOAT_TRUNCATE, "float_truncate", "e", RTX_UNARY)

/* Conversion of fixed point operand to floating point value.  */
DEF_RTL_EXPR(FLOAT, "float", "e", RTX_UNARY)

/* With fixed-point machine mode:
   Conversion of floating point operand to fixed point value.
   Value is defined only when the operand's value is an integer.
   With floating-point machine mode (and operand with same mode):
   Operand is rounded toward zero to produce an integer value
   represented in floating point.  */
DEF_RTL_EXPR(FIX, "fix", "e", RTX_UNARY)

/* Conversion of unsigned fixed point operand to floating point value.  */
DEF_RTL_EXPR(UNSIGNED_FLOAT, "unsigned_float", "e", RTX_UNARY)

/* With fixed-point machine mode:
   Conversion of floating point operand to *unsigned* fixed point value.
   Value is defined only when the operand's value is an integer.  */
DEF_RTL_EXPR(UNSIGNED_FIX, "unsigned_fix", "e", RTX_UNARY)

/* Conversions involving fractional fixed-point types without saturation,
   including:
     fractional to fractional (of different precision),
     signed integer to fractional,
     fractional to signed integer,
     floating point to fractional,
     fractional to floating point.
   NOTE: fractional can be either signed or unsigned for conversions.  */
DEF_RTL_EXPR(FRACT_CONVERT, "fract_convert", "e", RTX_UNARY)

/* Conversions involving fractional fixed-point types and unsigned integer
   without saturation, including:
     unsigned integer to fractional,
     fractional to unsigned integer.
   NOTE: fractional can be either signed or unsigned for conversions.  */
DEF_RTL_EXPR(UNSIGNED_FRACT_CONVERT, "unsigned_fract_convert", "e", RTX_UNARY)

/* Conversions involving fractional fixed-point types with saturation,
   including:
     fractional to fractional (of different precision),
     signed integer to fractional,
     floating point to fractional.
   NOTE: fractional can be either signed or unsigned for conversions.  */
DEF_RTL_EXPR(SAT_FRACT, "sat_fract", "e", RTX_UNARY)

/* Conversions involving fractional fixed-point types and unsigned integer
   with saturation, including:
     unsigned integer to fractional.
   NOTE: fractional can be either signed or unsigned for conversions.  */
DEF_RTL_EXPR(UNSIGNED_SAT_FRACT, "unsigned_sat_fract", "e", RTX_UNARY)

/* Absolute value */
DEF_RTL_EXPR(ABS, "abs", "e", RTX_UNARY)

/* Square root */
DEF_RTL_EXPR(SQRT, "sqrt", "e", RTX_UNARY)

/* Swap bytes.  */
DEF_RTL_EXPR(BSWAP, "bswap", "e", RTX_UNARY)

/* Find first bit that is set.
   Value is 1 + number of trailing zeros in the arg.,
   or 0 if arg is 0.  */
DEF_RTL_EXPR(FFS, "ffs", "e", RTX_UNARY)

/* Count number of leading redundant sign bits (number of leading
   sign bits minus one).  */
DEF_RTL_EXPR(CLRSB, "clrsb", "e", RTX_UNARY)

/* Count leading zeros.  */
DEF_RTL_EXPR(CLZ, "clz", "e", RTX_UNARY)

/* Count trailing zeros.  */
DEF_RTL_EXPR(CTZ, "ctz", "e", RTX_UNARY)

/* Population count (number of 1 bits).  */
DEF_RTL_EXPR(POPCOUNT, "popcount", "e", RTX_UNARY)

/* Population parity (number of 1 bits modulo 2).  */
DEF_RTL_EXPR(PARITY, "parity", "e", RTX_UNARY)

/* Reference to a signed bit-field of specified size and position.
   Operand 0 is the memory unit (usually SImode or QImode) which
   contains the field's first bit.  Operand 1 is the width, in bits.
   Operand 2 is the number of bits in the memory unit before the
   first bit of this field.
   If BITS_BIG_ENDIAN is defined, the first bit is the msb and
   operand 2 counts from the msb of the memory unit.
   Otherwise, the first bit is the lsb and operand 2 counts from
   the lsb of the memory unit.
   This kind of expression can not appear as an lvalue in RTL.  */
DEF_RTL_EXPR(SIGN_EXTRACT, "sign_extract", "eee", RTX_BITFIELD_OPS)

/* Similar for unsigned bit-field.
   But note!  This kind of expression _can_ appear as an lvalue.  */
DEF_RTL_EXPR(ZERO_EXTRACT, "zero_extract", "eee", RTX_BITFIELD_OPS)

/* For RISC machines.  These save memory when splitting insns.  */

/* HIGH are the high-order bits of a constant expression.  */
DEF_RTL_EXPR(HIGH, "high", "e", RTX_CONST_OBJ)

/* LO_SUM is the sum of a register and the low-order bits
   of a constant expression.  */
DEF_RTL_EXPR(LO_SUM, "lo_sum", "ee", RTX_OBJ)

/* Describes a merge operation between two vector values.
   Operands 0 and 1 are the vectors to be merged, operand 2 is a bitmask
   that specifies where the parts of the result are taken from.  Set bits
   indicate operand 0, clear bits indicate operand 1.  The parts are defined
   by the mode of the vectors.  */
DEF_RTL_EXPR(VEC_MERGE, "vec_merge", "eee", RTX_TERNARY)

/* Describes an operation that selects parts of a vector.
   Operands 0 is the source vector, operand 1 is a PARALLEL that contains
   a CONST_INT for each of the subparts of the result vector, giving the
   number of the source subpart that should be stored into it.  */
DEF_RTL_EXPR(VEC_SELECT, "vec_select", "ee", RTX_BIN_ARITH)

/* Describes a vector concat operation.  Operands 0 and 1 are the source
   vectors, the result is a vector that is as long as operands 0 and 1
   combined and is the concatenation of the two source vectors.  */
DEF_RTL_EXPR(VEC_CONCAT, "vec_concat", "ee", RTX_BIN_ARITH)

/* Describes an operation that converts a small vector into a larger one by
   duplicating the input values.  The output vector mode must have the same
   submodes as the input vector mode, and the number of output parts must be
   an integer multiple of the number of input parts.  */
DEF_RTL_EXPR(VEC_DUPLICATE, "vec_duplicate", "e", RTX_UNARY)

/* Addition with signed saturation */
DEF_RTL_EXPR(SS_PLUS, "ss_plus", "ee", RTX_COMM_ARITH)

/* Addition with unsigned saturation */
DEF_RTL_EXPR(US_PLUS, "us_plus", "ee", RTX_COMM_ARITH)

/* Operand 0 minus operand 1, with signed saturation.  */
DEF_RTL_EXPR(SS_MINUS, "ss_minus", "ee", RTX_BIN_ARITH)

/* Negation with signed saturation.  */
DEF_RTL_EXPR(SS_NEG, "ss_neg", "e", RTX_UNARY)
/* Negation with unsigned saturation.  */
DEF_RTL_EXPR(US_NEG, "us_neg", "e", RTX_UNARY)

/* Absolute value with signed saturation.  */
DEF_RTL_EXPR(SS_ABS, "ss_abs", "e", RTX_UNARY)

/* Shift left with signed saturation.  */
DEF_RTL_EXPR(SS_ASHIFT, "ss_ashift", "ee", RTX_BIN_ARITH)

/* Shift left with unsigned saturation.  */
DEF_RTL_EXPR(US_ASHIFT, "us_ashift", "ee", RTX_BIN_ARITH)

/* Operand 0 minus operand 1, with unsigned saturation.  */
DEF_RTL_EXPR(US_MINUS, "us_minus", "ee", RTX_BIN_ARITH)

/* Signed saturating truncate.  */
DEF_RTL_EXPR(SS_TRUNCATE, "ss_truncate", "e", RTX_UNARY)

/* Unsigned saturating truncate.  */
DEF_RTL_EXPR(US_TRUNCATE, "us_truncate", "e", RTX_UNARY)

/* Floating point multiply/add combined instruction.  */
DEF_RTL_EXPR(FMA, "fma", "eee", RTX_TERNARY)

/* Information about the variable and its location.  */
/* Changed 'te' to 'tei'; the 'i' field is for recording
   initialization status of variables.  */
DEF_RTL_EXPR(VAR_LOCATION, "var_location", "tei", RTX_EXTRA)

/* Used in VAR_LOCATION for a pointer to a decl that is no longer
   addressable.  */
DEF_RTL_EXPR(DEBUG_IMPLICIT_PTR, "debug_implicit_ptr", "t", RTX_OBJ)

/* Represents value that argument had on function entry.  The
   single argument is the DECL_INCOMING_RTL of the corresponding
   parameter.  */
DEF_RTL_EXPR(ENTRY_VALUE, "entry_value", "0", RTX_OBJ)

/* Used in VAR_LOCATION for a reference to a parameter that has
   been optimized away completely.  */
DEF_RTL_EXPR(DEBUG_PARAMETER_REF, "debug_parameter_ref", "t", RTX_OBJ)

/* All expressions from this point forward appear only in machine
   descriptions.  */
#ifdef GENERATOR_FILE

/* Pattern-matching operators:  */

/* Use the function named by the second arg (the string)
   as a predicate; if matched, store the structure that was matched
   in the operand table at index specified by the first arg (the integer).
   If the second arg is the null string, the structure is just stored.

   A third string argument indicates to the register allocator restrictions
   on where the operand can be allocated.

   If the target needs no restriction on any instruction this field should
   be the null string.

   The string is prepended by:
   '=' to indicate the operand is only written to.
   '+' to indicate the operand is both read and written to.

   Each character in the string represents an allocable class for an operand.
   'g' indicates the operand can be any valid class.
   'i' indicates the operand can be immediate (in the instruction) data.
   'r' indicates the operand can be in a register.
   'm' indicates the operand can be in memory.
   'o' a subset of the 'm' class.  Those memory addressing modes that
       can be offset at compile time (have a constant added to them).

   Other characters indicate target dependent operand classes and
   are described in each target's machine description.

   For instructions with more than one operand, sets of classes can be
   separated by a comma to indicate the appropriate multi-operand constraints.
   There must be a 1 to 1 correspondence between these sets of classes in
   all operands for an instruction.
   */
DEF_RTL_EXPR(MATCH_OPERAND, "match_operand", "iss", RTX_MATCH)

/* Match a SCRATCH or a register.  When used to generate rtl, a
   SCRATCH is generated.  As for MATCH_OPERAND, the mode specifies
   the desired mode and the first argument is the operand number.
   The second argument is the constraint.  */
DEF_RTL_EXPR(MATCH_SCRATCH, "match_scratch", "is", RTX_MATCH)

/* Apply a predicate, AND match recursively the operands of the rtx.
   Operand 0 is the operand-number, as in match_operand.
   Operand 1 is a predicate to apply (as a string, a function name).
   Operand 2 is a vector of expressions, each of which must match
   one subexpression of the rtx this construct is matching.  */
DEF_RTL_EXPR(MATCH_OPERATOR, "match_operator", "isE", RTX_MATCH)

/* Match a PARALLEL of arbitrary length.  The predicate is applied
   to the PARALLEL and the initial expressions in the PARALLEL are matched.
   Operand 0 is the operand-number, as in match_operand.
   Operand 1 is a predicate to apply to the PARALLEL.
   Operand 2 is a vector of expressions, each of which must match the
   corresponding element in the PARALLEL.  */
DEF_RTL_EXPR(MATCH_PARALLEL, "match_parallel", "isE", RTX_MATCH)

/* Match only something equal to what is stored in the operand table
   at the index specified by the argument.  Use with MATCH_OPERAND.  */
DEF_RTL_EXPR(MATCH_DUP, "match_dup", "i", RTX_MATCH)

/* Match only something equal to what is stored in the operand table
   at the index specified by the argument.  Use with MATCH_OPERATOR.  */
DEF_RTL_EXPR(MATCH_OP_DUP, "match_op_dup", "iE", RTX_MATCH)

/* Match only something equal to what is stored in the operand table
   at the index specified by the argument.  Use with MATCH_PARALLEL.  */
DEF_RTL_EXPR(MATCH_PAR_DUP, "match_par_dup", "iE", RTX_MATCH)

/* Appears only in define_predicate/define_special_predicate
   expressions.  Evaluates true only if the operand has an RTX code
   from the set given by the argument (a comma-separated list).  If the
   second argument is present and nonempty, it is a sequence of digits
   and/or letters which indicates the subexpression to test, using the
   same syntax as genextract/genrecog's location strings: 0-9 for
   XEXP (op, n), a-z for XVECEXP (op, 0, n); each character applies to
   the result of the one before it.  */
DEF_RTL_EXPR(MATCH_CODE, "match_code", "ss", RTX_MATCH)

/* Used to inject a C conditional expression into an .md file.  It can
   appear in a predicate definition or an attribute expression.  */
DEF_RTL_EXPR(MATCH_TEST, "match_test", "s", RTX_MATCH)

/* Insn (and related) definitions.  */

/* Definition of the pattern for one kind of instruction.
   Operand:
   0: names this instruction.
      If the name is the null string, the instruction is in the
      machine description just to be recognized, and will never be emitted by
      the tree to rtl expander.
   1: is the pattern.
   2: is a string which is a C expression
      giving an additional condition for recognizing this pattern.
      A null string means no extra condition.
   3: is the action to execute if this pattern is matched.
      If this assembler code template starts with a * then it is a fragment of
      C code to run to decide on a template to use.  Otherwise, it is the
      template to use.
   4: optionally, a vector of attributes for this insn.
     */
DEF_RTL_EXPR(DEFINE_INSN, "define_insn", "sEsTV", RTX_EXTRA)

/* Definition of a peephole optimization.
   1st operand: vector of insn patterns to match
   2nd operand: C expression that must be true
   3rd operand: template or C code to produce assembler output.
   4: optionally, a vector of attributes for this insn.

   This form is deprecated; use define_peephole2 instead.  */
DEF_RTL_EXPR(DEFINE_PEEPHOLE, "define_peephole", "EsTV", RTX_EXTRA)

/* Definition of a split operation.
   1st operand: insn pattern to match
   2nd operand: C expression that must be true
   3rd operand: vector of insn patterns to place into a SEQUENCE
   4th operand: optionally, some C code to execute before generating the
	insns.  This might, for example, create some RTX's and store them in
	elements of `recog_data.operand' for use by the vector of
	insn-patterns.
	(`operands' is an alias here for `recog_data.operand').  */
DEF_RTL_EXPR(DEFINE_SPLIT, "define_split", "EsES", RTX_EXTRA)

/* Definition of an insn and associated split.
   This is the concatenation, with a few modifications, of a define_insn
   and a define_split which share the same pattern.
   Operand:
   0: names this instruction.
      If the name is the null string, the instruction is in the
      machine description just to be recognized, and will never be emitted by
      the tree to rtl expander.
   1: is the pattern.
   2: is a string which is a C expression
      giving an additional condition for recognizing this pattern.
      A null string means no extra condition.
   3: is the action to execute if this pattern is matched.
      If this assembler code template starts with a * then it is a fragment of
      C code to run to decide on a template to use.  Otherwise, it is the
      template to use.
   4: C expression that must be true for split.  This may start with "&&"
      in which case the split condition is the logical and of the insn
      condition and what follows the "&&" of this operand.
   5: vector of insn patterns to place into a SEQUENCE
   6: optionally, some C code to execute before generating the
	insns.  This might, for example, create some RTX's and store them in
	elements of `recog_data.operand' for use by the vector of
	insn-patterns.
	(`operands' is an alias here for `recog_data.operand').
   7: optionally, a vector of attributes for this insn.  */
DEF_RTL_EXPR(DEFINE_INSN_AND_SPLIT, "define_insn_and_split", "sEsTsESV", RTX_EXTRA)

/* Definition of an RTL peephole operation.
   Follows the same arguments as define_split.  */
DEF_RTL_EXPR(DEFINE_PEEPHOLE2, "define_peephole2", "EsES", RTX_EXTRA)

/* Define how to generate multiple insns for a standard insn name.
   1st operand: the insn name.
   2nd operand: vector of insn-patterns.
	Use match_operand to substitute an element of `recog_data.operand'.
   3rd operand: C expression that must be true for this to be available.
	This may not test any operands.
   4th operand: Extra C code to execute before generating the insns.
	This might, for example, create some RTX's and store them in
	elements of `recog_data.operand' for use by the vector of
	insn-patterns.
	(`operands' is an alias here for `recog_data.operand').
   5th: optionally, a vector of attributes for this expand.  */
DEF_RTL_EXPR(DEFINE_EXPAND, "define_expand", "sEssV", RTX_EXTRA)

/* Define a requirement for delay slots.
   1st operand: Condition involving insn attributes that, if true,
	        indicates that the insn requires the number of delay slots
		shown.
   2nd operand: Vector whose length is the three times the number of delay
		slots required.
	        Each entry gives three conditions, each involving attributes.
		The first must be true for an insn to occupy that delay slot
		location.  The second is true for all insns that can be
		annulled if the branch is true and the third is true for all
		insns that can be annulled if the branch is false.

   Multiple DEFINE_DELAYs may be present.  They indicate differing
   requirements for delay slots.  */
DEF_RTL_EXPR(DEFINE_DELAY, "define_delay", "eE", RTX_EXTRA)

/* Define attribute computation for `asm' instructions.  */
DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES, "define_asm_attributes", "V", RTX_EXTRA)

/* Definition of a conditional execution meta operation.  Automatically
   generates new instances of DEFINE_INSN, selected by having attribute
   "predicable" true.  The new pattern will contain a COND_EXEC and the
   predicate at top-level.

   Operand:
   0: The predicate pattern.  The top-level form should match a
      relational operator.  Operands should have only one alternative.
   1: A C expression giving an additional condition for recognizing
      the generated pattern.
   2: A template or C code to produce assembler output.
   3: A vector of attributes to append to the resulting cond_exec insn.  */
DEF_RTL_EXPR(DEFINE_COND_EXEC, "define_cond_exec", "EssV", RTX_EXTRA)

/* Definition of an operand predicate.  The difference between
   DEFINE_PREDICATE and DEFINE_SPECIAL_PREDICATE is that genrecog will
   not warn about a match_operand with no mode if it has a predicate
   defined with DEFINE_SPECIAL_PREDICATE.

   Operand:
   0: The name of the predicate.
   1: A boolean expression which computes whether or not the predicate
      matches.  This expression can use IOR, AND, NOT, MATCH_OPERAND,
      MATCH_CODE, and MATCH_TEST.  It must be specific enough that genrecog
      can calculate the set of RTX codes that can possibly match.
   2: A C function body which must return true for the predicate to match.
      Optional.  Use this when the test is too complicated to fit into a
      match_test expression.  */
DEF_RTL_EXPR(DEFINE_PREDICATE, "define_predicate", "ses", RTX_EXTRA)
DEF_RTL_EXPR(DEFINE_SPECIAL_PREDICATE, "define_special_predicate", "ses", RTX_EXTRA)

/* Definition of a register operand constraint.  This simply maps the
   constraint string to a register class.

   Operand:
   0: The name of the constraint (often, but not always, a single letter).
   1: A C expression which evaluates to the appropriate register class for
      this constraint.  If this is not just a constant, it should look only
      at -m switches and the like.
   2: A docstring for this constraint, in Texinfo syntax; not currently
      used, in future will be incorporated into the manual's list of
      machine-specific operand constraints.  */
DEF_RTL_EXPR(DEFINE_REGISTER_CONSTRAINT, "define_register_constraint", "sss", RTX_EXTRA)

/* Definition of a non-register operand constraint.  These look at the
   operand and decide whether it fits the constraint.

   DEFINE_CONSTRAINT gets no special treatment if it fails to match.
   It is appropriate for constant-only constraints, and most others.

   DEFINE_MEMORY_CONSTRAINT tells reload that this constraint can be made
   to match, if it doesn't already, by converting the operand to the form
   (mem (reg X)) where X is a base register.  It is suitable for constraints
   that describe a subset of all memory references.

   DEFINE_ADDRESS_CONSTRAINT tells reload that this constraint can be made
   to match, if it doesn't already, by converting the operand to the form
   (reg X) where X is a base register.  It is suitable for constraints that
   describe a subset of all address references.

   When in doubt, use plain DEFINE_CONSTRAINT.

   Operand:
   0: The name of the constraint (often, but not always, a single letter).
   1: A docstring for this constraint, in Texinfo syntax; not currently
      used, in future will be incorporated into the manual's list of
      machine-specific operand constraints.
   2: A boolean expression which computes whether or not the constraint
      matches.  It should follow the same rules as a define_predicate
      expression, including the bit about specifying the set of RTX codes
      that could possibly match.  MATCH_TEST subexpressions may make use of
      these variables:
        `op'    - the RTL object defining the operand.
        `mode'  - the mode of `op'.
	`ival'  - INTVAL(op), if op is a CONST_INT.
        `hval'  - CONST_DOUBLE_HIGH(op), if op is an integer CONST_DOUBLE.
        `lval'  - CONST_DOUBLE_LOW(op), if op is an integer CONST_DOUBLE.
        `rval'  - CONST_DOUBLE_REAL_VALUE(op), if op is a floating-point
                  CONST_DOUBLE.
      Do not use ival/hval/lval/rval if op is not the appropriate kind of
      RTL object.  */
DEF_RTL_EXPR(DEFINE_CONSTRAINT, "define_constraint", "sse", RTX_EXTRA)
DEF_RTL_EXPR(DEFINE_MEMORY_CONSTRAINT, "define_memory_constraint", "sse", RTX_EXTRA)
DEF_RTL_EXPR(DEFINE_ADDRESS_CONSTRAINT, "define_address_constraint", "sse", RTX_EXTRA)


/* Constructions for CPU pipeline description described by NDFAs.  */

/* (define_cpu_unit string [string]) describes cpu functional
   units (separated by comma).

   1st operand: Names of cpu functional units.
   2nd operand: Name of automaton (see comments for DEFINE_AUTOMATON).

   All define_reservations, define_cpu_units, and
   define_query_cpu_units should have unique names which may not be
   "nothing".  */
DEF_RTL_EXPR(DEFINE_CPU_UNIT, "define_cpu_unit", "sS", RTX_EXTRA)

/* (define_query_cpu_unit string [string]) describes cpu functional
   units analogously to define_cpu_unit.  The reservation of such
   units can be queried for automaton state.  */
DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT, "define_query_cpu_unit", "sS", RTX_EXTRA)

/* (exclusion_set string string) means that each CPU functional unit
   in the first string can not be reserved simultaneously with any
   unit whose name is in the second string and vise versa.  CPU units
   in the string are separated by commas.  For example, it is useful
   for description CPU with fully pipelined floating point functional
   unit which can execute simultaneously only single floating point
   insns or only double floating point insns.  All CPU functional
   units in a set should belong to the same automaton.  */
DEF_RTL_EXPR(EXCLUSION_SET, "exclusion_set", "ss", RTX_EXTRA)

/* (presence_set string string) means that each CPU functional unit in
   the first string can not be reserved unless at least one of pattern
   of units whose names are in the second string is reserved.  This is
   an asymmetric relation.  CPU units or unit patterns in the strings
   are separated by commas.  Pattern is one unit name or unit names
   separated by white-spaces.

   For example, it is useful for description that slot1 is reserved
   after slot0 reservation for a VLIW processor.  We could describe it
   by the following construction

      (presence_set "slot1" "slot0")

   Or slot1 is reserved only after slot0 and unit b0 reservation.  In
   this case we could write

      (presence_set "slot1" "slot0 b0")

   All CPU functional units in a set should belong to the same
   automaton.  */
DEF_RTL_EXPR(PRESENCE_SET, "presence_set", "ss", RTX_EXTRA)

/* (final_presence_set string string) is analogous to `presence_set'.
   The difference between them is when checking is done.  When an
   instruction is issued in given automaton state reflecting all
   current and planned unit reservations, the automaton state is
   changed.  The first state is a source state, the second one is a
   result state.  Checking for `presence_set' is done on the source
   state reservation, checking for `final_presence_set' is done on the
   result reservation.  This construction is useful to describe a
   reservation which is actually two subsequent reservations.  For
   example, if we use

      (presence_set "slot1" "slot0")

   the following insn will be never issued (because slot1 requires
   slot0 which is absent in the source state).

      (define_reservation "insn_and_nop" "slot0 + slot1")

   but it can be issued if we use analogous `final_presence_set'.  */
DEF_RTL_EXPR(FINAL_PRESENCE_SET, "final_presence_set", "ss", RTX_EXTRA)

/* (absence_set string string) means that each CPU functional unit in
   the first string can be reserved only if each pattern of units
   whose names are in the second string is not reserved.  This is an
   asymmetric relation (actually exclusion set is analogous to this
   one but it is symmetric).  CPU units or unit patterns in the string
   are separated by commas.  Pattern is one unit name or unit names
   separated by white-spaces.

   For example, it is useful for description that slot0 can not be
   reserved after slot1 or slot2 reservation for a VLIW processor.  We
   could describe it by the following construction

      (absence_set "slot2" "slot0, slot1")

   Or slot2 can not be reserved if slot0 and unit b0 are reserved or
   slot1 and unit b1 are reserved .  In this case we could write

      (absence_set "slot2" "slot0 b0, slot1 b1")

   All CPU functional units in a set should to belong the same
   automaton.  */
DEF_RTL_EXPR(ABSENCE_SET, "absence_set", "ss", RTX_EXTRA)

/* (final_absence_set string string) is analogous to `absence_set' but
   checking is done on the result (state) reservation.  See comments
   for `final_presence_set'.  */
DEF_RTL_EXPR(FINAL_ABSENCE_SET, "final_absence_set", "ss", RTX_EXTRA)

/* (define_bypass number out_insn_names in_insn_names) names bypass
   with given latency (the first number) from insns given by the first
   string (see define_insn_reservation) into insns given by the second
   string.  Insn names in the strings are separated by commas.  The
   third operand is optional name of function which is additional
   guard for the bypass.  The function will get the two insns as
   parameters.  If the function returns zero the bypass will be
   ignored for this case.  Additional guard is necessary to recognize
   complicated bypasses, e.g. when consumer is load address.  If there
   are more one bypass with the same output and input insns, the
   chosen bypass is the first bypass with a guard in description whose
   guard function returns nonzero.  If there is no such bypass, then
   bypass without the guard function is chosen.  */
DEF_RTL_EXPR(DEFINE_BYPASS, "define_bypass", "issS", RTX_EXTRA)

/* (define_automaton string) describes names of automata generated and
   used for pipeline hazards recognition.  The names are separated by
   comma.  Actually it is possibly to generate the single automaton
   but unfortunately it can be very large.  If we use more one
   automata, the summary size of the automata usually is less than the
   single one.  The automaton name is used in define_cpu_unit and
   define_query_cpu_unit.  All automata should have unique names.  */
DEF_RTL_EXPR(DEFINE_AUTOMATON, "define_automaton", "s", RTX_EXTRA)

/* (automata_option string) describes option for generation of
   automata.  Currently there are the following options:

   o "no-minimization" which makes no minimization of automata.  This
     is only worth to do when we are debugging the description and
     need to look more accurately at reservations of states.

   o "time" which means printing additional time statistics about
      generation of automata.

   o "v" which means generation of file describing the result
     automata.  The file has suffix `.dfa' and can be used for the
     description verification and debugging.

   o "w" which means generation of warning instead of error for
     non-critical errors.

   o "ndfa" which makes nondeterministic finite state automata.

   o "progress" which means output of a progress bar showing how many
     states were generated so far for automaton being processed.  */
DEF_RTL_EXPR(AUTOMATA_OPTION, "automata_option", "s", RTX_EXTRA)

/* (define_reservation string string) names reservation (the first
   string) of cpu functional units (the 2nd string).  Sometimes unit
   reservations for different insns contain common parts.  In such
   case, you can describe common part and use its name (the 1st
   parameter) in regular expression in define_insn_reservation.  All
   define_reservations, define_cpu_units, and define_query_cpu_units
   should have unique names which may not be "nothing".  */
DEF_RTL_EXPR(DEFINE_RESERVATION, "define_reservation", "ss", RTX_EXTRA)

/* (define_insn_reservation name default_latency condition regexpr)
   describes reservation of cpu functional units (the 3nd operand) for
   instruction which is selected by the condition (the 2nd parameter).
   The first parameter is used for output of debugging information.
   The reservations are described by a regular expression according
   the following syntax:

       regexp = regexp "," oneof
              | oneof

       oneof = oneof "|" allof
             | allof

       allof = allof "+" repeat
             | repeat

       repeat = element "*" number
              | element

       element = cpu_function_unit_name
               | reservation_name
               | result_name
               | "nothing"
               | "(" regexp ")"

       1. "," is used for describing start of the next cycle in
       reservation.

       2. "|" is used for describing the reservation described by the
       first regular expression *or* the reservation described by the
       second regular expression *or* etc.

       3. "+" is used for describing the reservation described by the
       first regular expression *and* the reservation described by the
       second regular expression *and* etc.

       4. "*" is used for convenience and simply means sequence in
       which the regular expression are repeated NUMBER times with
       cycle advancing (see ",").

       5. cpu functional unit name which means its reservation.

       6. reservation name -- see define_reservation.

       7. string "nothing" means no units reservation.  */

DEF_RTL_EXPR(DEFINE_INSN_RESERVATION, "define_insn_reservation", "sies", RTX_EXTRA)

/* Expressions used for insn attributes.  */

/* Definition of an insn attribute.
   1st operand: name of the attribute
   2nd operand: comma-separated list of possible attribute values
   3rd operand: expression for the default value of the attribute.  */
DEF_RTL_EXPR(DEFINE_ATTR, "define_attr", "sse", RTX_EXTRA)

/* Definition of an insn attribute that uses an existing enumerated type.
   1st operand: name of the attribute
   2nd operand: the name of the enumerated type
   3rd operand: expression for the default value of the attribute.  */
DEF_RTL_EXPR(DEFINE_ENUM_ATTR, "define_enum_attr", "sse", RTX_EXTRA)

/* Marker for the name of an attribute.  */
DEF_RTL_EXPR(ATTR, "attr", "s", RTX_EXTRA)

/* For use in the last (optional) operand of DEFINE_INSN or DEFINE_PEEPHOLE and
   in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that
   pattern.

   (set_attr "name" "value") is equivalent to
   (set (attr "name") (const_string "value"))  */
DEF_RTL_EXPR(SET_ATTR, "set_attr", "ss", RTX_EXTRA)

/* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE, this can be used to
   specify that attribute values are to be assigned according to the
   alternative matched.

   The following three expressions are equivalent:

   (set (attr "att") (cond [(eq_attrq "alternative" "1") (const_string "a1")
			    (eq_attrq "alternative" "2") (const_string "a2")]
			   (const_string "a3")))
   (set_attr_alternative "att" [(const_string "a1") (const_string "a2")
				 (const_string "a3")])
   (set_attr "att" "a1,a2,a3")
 */
DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE, "set_attr_alternative", "sE", RTX_EXTRA)

/* A conditional expression true if the value of the specified attribute of
   the current insn equals the specified value.  The first operand is the
   attribute name and the second is the comparison value.  */
DEF_RTL_EXPR(EQ_ATTR, "eq_attr", "ss", RTX_EXTRA)

/* A special case of the above representing a set of alternatives.  The first
   operand is bitmap of the set, the second one is the default value.  */
DEF_RTL_EXPR(EQ_ATTR_ALT, "eq_attr_alt", "ii", RTX_EXTRA)

/* A conditional expression which is true if the specified flag is
   true for the insn being scheduled in reorg.

   genattr.c defines the following flags which can be tested by
   (attr_flag "foo") expressions in eligible_for_delay: forward, backward.  */

DEF_RTL_EXPR (ATTR_FLAG, "attr_flag", "s", RTX_EXTRA)

/* General conditional. The first operand is a vector composed of pairs of
   expressions.  The first element of each pair is evaluated, in turn.
   The value of the conditional is the second expression of the first pair
   whose first expression evaluates nonzero.  If none of the expressions is
   true, the second operand will be used as the value of the conditional.  */
DEF_RTL_EXPR(COND, "cond", "Ee", RTX_EXTRA)

/* Definition of a pattern substitution meta operation on a DEFINE_EXPAND
   or a DEFINE_INSN.  Automatically generates new instances of DEFINE_INSNs
   that match the substitution pattern.

   Operand:
   0: The name of the substitition template.
   1: Input template to match to see if a substitution is applicable.
   2: A C expression giving an additional condition for the generated
      new define_expand or define_insn.
   3: Output tempalate to generate via substitution.

   Within a DEFINE_SUBST template, the meaning of some RTL expressions is
   different from their usual interpretation: a MATCH_OPERAND matches any
   expression tree with matching machine mode or with VOIDmode.  Likewise,
   MATCH_OP_DUP and MATCH_DUP match more liberally in a DEFINE_SUBST than
   in other RTL expressions.  MATCH_OPERATOR matches all common operators
   but also UNSPEC, UNSPEC_VOLATILE, and MATCH_OPERATORS from the input
   DEFINE_EXPAND or DEFINE_INSN.  */
DEF_RTL_EXPR(DEFINE_SUBST, "define_subst", "sEsE", RTX_EXTRA)

/* Substitution attribute to apply a DEFINE_SUBST to a pattern.

   Operand:
   0: The name of the subst-attribute.
   1: The name of the DEFINE_SUBST to be applied for this attribute.
   2: String to substitute for the subst-attribute name in the pattern
      name, for the case that the DEFINE_SUBST is not applied (i.e. the
      unmodified version of the pattern).
   3: String to substitute for the subst-attribute name in the pattern
      name, for the case that the DEFINE_SUBST is applied to the patten.
      
   The use of DEFINE_SUBST and DEFINE_SUBST_ATTR is explained in the
   GCC internals manual, under "RTL Templates Transformations".  */
DEF_RTL_EXPR(DEFINE_SUBST_ATTR, "define_subst_attr", "ssss", RTX_EXTRA)

#endif /* GENERATOR_FILE */

/*
Local variables:
mode:c
End:
*/