combine.c (expand_compound_operation): Add comment that we fall through after case.
[gcc.git] / gcc / rtl.def
1 /* This file contains the definitions and documentation for the
2 Register Transfer Expressions (rtx's) that make up the
3 Register Transfer Language (rtl) used in the Back End of the GNU compiler.
4 Copyright (C) 1987, 1988, 1992, 1994, 1995, 1997, 1998, 1999, 2000, 2004
5 Free Software Foundation, Inc.
6
7 This file is part of GCC.
8
9 GCC is free software; you can redistribute it and/or modify it under
10 the terms of the GNU General Public License as published by the Free
11 Software Foundation; either version 2, or (at your option) any later
12 version.
13
14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to the Free
21 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 02111-1307, USA. */
23
24
25 /* Expression definitions and descriptions for all targets are in this file.
26 Some will not be used for some targets.
27
28 The fields in the cpp macro call "DEF_RTL_EXPR()"
29 are used to create declarations in the C source of the compiler.
30
31 The fields are:
32
33 1. The internal name of the rtx used in the C source.
34 It is a tag in the enumeration "enum rtx_code" defined in "rtl.h".
35 By convention these are in UPPER_CASE.
36
37 2. The name of the rtx in the external ASCII format read by
38 read_rtx(), and printed by print_rtx().
39 These names are stored in rtx_name[].
40 By convention these are the internal (field 1) names in lower_case.
41
42 3. The print format, and type of each rtx->u.fld[] (field) in this rtx.
43 These formats are stored in rtx_format[].
44 The meaning of the formats is documented in front of this array in rtl.c
45
46 4. The class of the rtx. These are stored in rtx_class and are accessed
47 via the GET_RTX_CLASS macro. They are defined as follows:
48
49 RTX_CONST_OBJ
50 an rtx code that can be used to represent a constant object
51 (e.g, CONST_INT)
52 RTX_OBJ
53 an rtx code that can be used to represent an object (e.g, REG, MEM)
54 RTX_COMPARE
55 an rtx code for a comparison (e.g, LT, GT)
56 RTX_COMM_COMPARE
57 an rtx code for a commutative comparison (e.g, EQ, NE, ORDERED)
58 RTX_UNARY
59 an rtx code for a unary arithmetic expression (e.g, NEG, NOT)
60 RTX_COMM_ARITH
61 an rtx code for a commutative binary operation (e.g,, PLUS, MULT)
62 RTX_TERNARY
63 an rtx code for a non-bitfield three input operation (IF_THEN_ELSE)
64 RTX_BIN_ARITH
65 an rtx code for a non-commutative binary operation (e.g., MINUS, DIV)
66 RTX_BITFIELD_OPS
67 an rtx code for a bit-field operation (ZERO_EXTRACT, SIGN_EXTRACT)
68 RTX_INSN
69 an rtx code for a machine insn (INSN, JUMP_INSN, CALL_INSN)
70 RTX_MATCH
71 an rtx code for something that matches in insns (e.g, MATCH_DUP)
72 RTX_AUTOINC
73 an rtx code for autoincrement addressing modes (e.g. POST_DEC)
74 RTX_EXTRA
75 everything else
76
77 All of the expressions that appear only in machine descriptions,
78 not in RTL used by the compiler itself, are at the end of the file. */
79
80 /* Unknown, or no such operation; the enumeration constant should have
81 value zero. */
82 DEF_RTL_EXPR(UNKNOWN, "UnKnown", "*", RTX_EXTRA)
83
84 /* ---------------------------------------------------------------------
85 Expressions used in constructing lists.
86 --------------------------------------------------------------------- */
87
88 /* a linked list of expressions */
89 DEF_RTL_EXPR(EXPR_LIST, "expr_list", "ee", RTX_EXTRA)
90
91 /* a linked list of instructions.
92 The insns are represented in print by their uids. */
93 DEF_RTL_EXPR(INSN_LIST, "insn_list", "ue", RTX_EXTRA)
94
95 /* SEQUENCE appears in the result of a `gen_...' function
96 for a DEFINE_EXPAND that wants to make several insns.
97 Its elements are the bodies of the insns that should be made.
98 `emit_insn' takes the SEQUENCE apart and makes separate insns. */
99 DEF_RTL_EXPR(SEQUENCE, "sequence", "E", RTX_EXTRA)
100
101 /* Refers to the address of its argument. This is only used in alias.c. */
102 DEF_RTL_EXPR(ADDRESS, "address", "e", RTX_MATCH)
103
104 /* ----------------------------------------------------------------------
105 Expression types used for things in the instruction chain.
106
107 All formats must start with "iuu" to handle the chain.
108 Each insn expression holds an rtl instruction and its semantics
109 during back-end processing.
110 See macros's in "rtl.h" for the meaning of each rtx->u.fld[].
111
112 ---------------------------------------------------------------------- */
113
114 /* An instruction that cannot jump. */
115 DEF_RTL_EXPR(INSN, "insn", "iuuBieiee", RTX_INSN)
116
117 /* An instruction that can possibly jump.
118 Fields ( rtx->u.fld[] ) have exact same meaning as INSN's. */
119 DEF_RTL_EXPR(JUMP_INSN, "jump_insn", "iuuBieiee0", RTX_INSN)
120
121 /* An instruction that can possibly call a subroutine
122 but which will not change which instruction comes next
123 in the current function.
124 Field ( rtx->u.fld[9] ) is CALL_INSN_FUNCTION_USAGE.
125 All other fields ( rtx->u.fld[] ) have exact same meaning as INSN's. */
126 DEF_RTL_EXPR(CALL_INSN, "call_insn", "iuuBieieee", RTX_INSN)
127
128 /* A marker that indicates that control will not flow through. */
129 DEF_RTL_EXPR(BARRIER, "barrier", "iuu000000", RTX_EXTRA)
130
131 /* Holds a label that is followed by instructions.
132 Operand:
133 4: is used in jump.c for the use-count of the label.
134 5: is used in flow.c to point to the chain of label_ref's to this label.
135 6: is a number that is unique in the entire compilation.
136 7: is the user-given name of the label, if any. */
137 DEF_RTL_EXPR(CODE_LABEL, "code_label", "iuuB00is", RTX_EXTRA)
138
139 #ifdef USE_MAPPED_LOCATION
140 /* Say where in the code a source line starts, for symbol table's sake.
141 Operand:
142 4: unused if line number > 0, note-specific data otherwise.
143 5: line number if > 0, enum note_insn otherwise.
144 6: CODE_LABEL_NUMBER if line number == NOTE_INSN_DELETED_LABEL. */
145 #else
146 /* Say where in the code a source line starts, for symbol table's sake.
147 Operand:
148 4: filename, if line number > 0, note-specific data otherwise.
149 5: line number if > 0, enum note_insn otherwise.
150 6: unique number if line number == note_insn_deleted_label. */
151 #endif
152 DEF_RTL_EXPR(NOTE, "note", "iuuB0ni", RTX_EXTRA)
153
154 /* ----------------------------------------------------------------------
155 Top level constituents of INSN, JUMP_INSN and CALL_INSN.
156 ---------------------------------------------------------------------- */
157
158 /* Conditionally execute code.
159 Operand 0 is the condition that if true, the code is executed.
160 Operand 1 is the code to be executed (typically a SET).
161
162 Semantics are that there are no side effects if the condition
163 is false. This pattern is created automatically by the if_convert
164 pass run after reload or by target-specific splitters. */
165 DEF_RTL_EXPR(COND_EXEC, "cond_exec", "ee", RTX_EXTRA)
166
167 /* Several operations to be done in parallel (perhaps under COND_EXEC). */
168 DEF_RTL_EXPR(PARALLEL, "parallel", "E", RTX_EXTRA)
169
170 /* A string that is passed through to the assembler as input.
171 One can obviously pass comments through by using the
172 assembler comment syntax.
173 These occur in an insn all by themselves as the PATTERN.
174 They also appear inside an ASM_OPERANDS
175 as a convenient way to hold a string. */
176 DEF_RTL_EXPR(ASM_INPUT, "asm_input", "s", RTX_EXTRA)
177
178 #ifdef USE_MAPPED_LOCATION
179 /* An assembler instruction with operands.
180 1st operand is the instruction template.
181 2nd operand is the constraint for the output.
182 3rd operand is the number of the output this expression refers to.
183 When an insn stores more than one value, a separate ASM_OPERANDS
184 is made for each output; this integer distinguishes them.
185 4th is a vector of values of input operands.
186 5th is a vector of modes and constraints for the input operands.
187 Each element is an ASM_INPUT containing a constraint string
188 and whose mode indicates the mode of the input operand.
189 6th is the source line number. */
190 DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEi", RTX_EXTRA)
191 #else
192 /* An assembler instruction with operands.
193 1st operand is the instruction template.
194 2nd operand is the constraint for the output.
195 3rd operand is the number of the output this expression refers to.
196 When an insn stores more than one value, a separate ASM_OPERANDS
197 is made for each output; this integer distinguishes them.
198 4th is a vector of values of input operands.
199 5th is a vector of modes and constraints for the input operands.
200 Each element is an ASM_INPUT containing a constraint string
201 and whose mode indicates the mode of the input operand.
202 6th is the name of the containing source file.
203 7th is the source line number. */
204 DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEsi", RTX_EXTRA)
205 #endif
206
207 /* A machine-specific operation.
208 1st operand is a vector of operands being used by the operation so that
209 any needed reloads can be done.
210 2nd operand is a unique value saying which of a number of machine-specific
211 operations is to be performed.
212 (Note that the vector must be the first operand because of the way that
213 genrecog.c record positions within an insn.)
214 This can occur all by itself in a PATTERN, as a component of a PARALLEL,
215 or inside an expression. */
216 DEF_RTL_EXPR(UNSPEC, "unspec", "Ei", RTX_EXTRA)
217
218 /* Similar, but a volatile operation and one which may trap. */
219 DEF_RTL_EXPR(UNSPEC_VOLATILE, "unspec_volatile", "Ei", RTX_EXTRA)
220
221 /* Vector of addresses, stored as full words. */
222 /* Each element is a LABEL_REF to a CODE_LABEL whose address we want. */
223 DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", RTX_EXTRA)
224
225 /* Vector of address differences X0 - BASE, X1 - BASE, ...
226 First operand is BASE; the vector contains the X's.
227 The machine mode of this rtx says how much space to leave
228 for each difference and is adjusted by branch shortening if
229 CASE_VECTOR_SHORTEN_MODE is defined.
230 The third and fourth operands store the target labels with the
231 minimum and maximum addresses respectively.
232 The fifth operand stores flags for use by branch shortening.
233 Set at the start of shorten_branches:
234 min_align: the minimum alignment for any of the target labels.
235 base_after_vec: true iff BASE is after the ADDR_DIFF_VEC.
236 min_after_vec: true iff minimum addr target label is after the ADDR_DIFF_VEC.
237 max_after_vec: true iff maximum addr target label is after the ADDR_DIFF_VEC.
238 min_after_base: true iff minimum address target label is after BASE.
239 max_after_base: true iff maximum address target label is after BASE.
240 Set by the actual branch shortening process:
241 offset_unsigned: true iff offsets have to be treated as unsigned.
242 scale: scaling that is necessary to make offsets fit into the mode.
243
244 The third, fourth and fifth operands are only valid when
245 CASE_VECTOR_SHORTEN_MODE is defined, and only in an optimizing
246 compilations. */
247
248 DEF_RTL_EXPR(ADDR_DIFF_VEC, "addr_diff_vec", "eEee0", RTX_EXTRA)
249
250 /* Memory prefetch, with attributes supported on some targets.
251 Operand 1 is the address of the memory to fetch.
252 Operand 2 is 1 for a write access, 0 otherwise.
253 Operand 3 is the level of temporal locality; 0 means there is no
254 temporal locality and 1, 2, and 3 are for increasing levels of temporal
255 locality.
256
257 The attributes specified by operands 2 and 3 are ignored for targets
258 whose prefetch instructions do not support them. */
259 DEF_RTL_EXPR(PREFETCH, "prefetch", "eee", RTX_EXTRA)
260
261 /* ----------------------------------------------------------------------
262 At the top level of an instruction (perhaps under PARALLEL).
263 ---------------------------------------------------------------------- */
264
265 /* Assignment.
266 Operand 1 is the location (REG, MEM, PC, CC0 or whatever) assigned to.
267 Operand 2 is the value stored there.
268 ALL assignment must use SET.
269 Instructions that do multiple assignments must use multiple SET,
270 under PARALLEL. */
271 DEF_RTL_EXPR(SET, "set", "ee", RTX_EXTRA)
272
273 /* Indicate something is used in a way that we don't want to explain.
274 For example, subroutine calls will use the register
275 in which the static chain is passed. */
276 DEF_RTL_EXPR(USE, "use", "e", RTX_EXTRA)
277
278 /* Indicate something is clobbered in a way that we don't want to explain.
279 For example, subroutine calls will clobber some physical registers
280 (the ones that are by convention not saved). */
281 DEF_RTL_EXPR(CLOBBER, "clobber", "e", RTX_EXTRA)
282
283 /* Call a subroutine.
284 Operand 1 is the address to call.
285 Operand 2 is the number of arguments. */
286
287 DEF_RTL_EXPR(CALL, "call", "ee", RTX_EXTRA)
288
289 /* Return from a subroutine. */
290
291 DEF_RTL_EXPR(RETURN, "return", "", RTX_EXTRA)
292
293 /* Conditional trap.
294 Operand 1 is the condition.
295 Operand 2 is the trap code.
296 For an unconditional trap, make the condition (const_int 1). */
297 DEF_RTL_EXPR(TRAP_IF, "trap_if", "ee", RTX_EXTRA)
298
299 /* Placeholder for _Unwind_Resume before we know if a function call
300 or a branch is needed. Operand 1 is the exception region from
301 which control is flowing. */
302 DEF_RTL_EXPR(RESX, "resx", "i", RTX_EXTRA)
303
304 /* ----------------------------------------------------------------------
305 Primitive values for use in expressions.
306 ---------------------------------------------------------------------- */
307
308 /* numeric integer constant */
309 DEF_RTL_EXPR(CONST_INT, "const_int", "w", RTX_CONST_OBJ)
310
311 /* numeric floating point constant.
312 Operands hold the value. They are all 'w' and there may be from 2 to 6;
313 see real.h. */
314 DEF_RTL_EXPR(CONST_DOUBLE, "const_double", CONST_DOUBLE_FORMAT, RTX_CONST_OBJ)
315
316 /* Describes a vector constant. */
317 DEF_RTL_EXPR(CONST_VECTOR, "const_vector", "E", RTX_EXTRA)
318
319 /* String constant. Used for attributes in machine descriptions and
320 for special cases in DWARF2 debug output. NOT used for source-
321 language string constants. */
322 DEF_RTL_EXPR(CONST_STRING, "const_string", "s", RTX_OBJ)
323
324 /* This is used to encapsulate an expression whose value is constant
325 (such as the sum of a SYMBOL_REF and a CONST_INT) so that it will be
326 recognized as a constant operand rather than by arithmetic instructions. */
327
328 DEF_RTL_EXPR(CONST, "const", "e", RTX_CONST_OBJ)
329
330 /* program counter. Ordinary jumps are represented
331 by a SET whose first operand is (PC). */
332 DEF_RTL_EXPR(PC, "pc", "", RTX_OBJ)
333
334 /* Used in the cselib routines to describe a value. Objects of this
335 kind are only allocated in cselib.c, in an alloc pool instead of
336 in GC memory. The only operand of a VALUE is a cselib_val_struct. */
337 DEF_RTL_EXPR(VALUE, "value", "0", RTX_OBJ)
338
339 /* A register. The "operand" is the register number, accessed with
340 the REGNO macro. If this number is less than FIRST_PSEUDO_REGISTER
341 than a hardware register is being referred to. The second operand
342 holds the original register number - this will be different for a
343 pseudo register that got turned into a hard register. The third
344 operand points to a reg_attrs structure.
345 This rtx needs to have as many (or more) fields as a MEM, since we
346 can change REG rtx's into MEMs during reload. */
347 DEF_RTL_EXPR(REG, "reg", "i00", RTX_OBJ)
348
349 /* A scratch register. This represents a register used only within a
350 single insn. It will be turned into a REG during register allocation
351 or reload unless the constraint indicates that the register won't be
352 needed, in which case it can remain a SCRATCH. This code is
353 marked as having one operand so it can be turned into a REG. */
354 DEF_RTL_EXPR(SCRATCH, "scratch", "0", RTX_OBJ)
355
356 /* One word of a multi-word value.
357 The first operand is the complete value; the second says which word.
358 The WORDS_BIG_ENDIAN flag controls whether word number 0
359 (as numbered in a SUBREG) is the most or least significant word.
360
361 This is also used to refer to a value in a different machine mode.
362 For example, it can be used to refer to a SImode value as if it were
363 Qimode, or vice versa. Then the word number is always 0. */
364 DEF_RTL_EXPR(SUBREG, "subreg", "ei", RTX_EXTRA)
365
366 /* This one-argument rtx is used for move instructions
367 that are guaranteed to alter only the low part of a destination.
368 Thus, (SET (SUBREG:HI (REG...)) (MEM:HI ...))
369 has an unspecified effect on the high part of REG,
370 but (SET (STRICT_LOW_PART (SUBREG:HI (REG...))) (MEM:HI ...))
371 is guaranteed to alter only the bits of REG that are in HImode.
372
373 The actual instruction used is probably the same in both cases,
374 but the register constraints may be tighter when STRICT_LOW_PART
375 is in use. */
376
377 DEF_RTL_EXPR(STRICT_LOW_PART, "strict_low_part", "e", RTX_EXTRA)
378
379 /* (CONCAT a b) represents the virtual concatenation of a and b
380 to make a value that has as many bits as a and b put together.
381 This is used for complex values. Normally it appears only
382 in DECL_RTLs and during RTL generation, but not in the insn chain. */
383 DEF_RTL_EXPR(CONCAT, "concat", "ee", RTX_OBJ)
384
385 /* A memory location; operand is the address. The second operand is the
386 alias set to which this MEM belongs. We use `0' instead of `w' for this
387 field so that the field need not be specified in machine descriptions. */
388 DEF_RTL_EXPR(MEM, "mem", "e0", RTX_OBJ)
389
390 /* Reference to an assembler label in the code for this function.
391 The operand is a CODE_LABEL found in the insn chain.
392 The unprinted field 1 is used in flow.c for the LABEL_NEXTREF. */
393 DEF_RTL_EXPR(LABEL_REF, "label_ref", "u0", RTX_CONST_OBJ)
394
395 /* Reference to a named label:
396 Operand 0: label name
397 Operand 1: flags (see SYMBOL_FLAG_* in rtl.h)
398 Operand 2: tree from which this symbol is derived, or null.
399 This is either a DECL node, or some kind of constant. */
400 DEF_RTL_EXPR(SYMBOL_REF, "symbol_ref", "s00", RTX_CONST_OBJ)
401
402 /* The condition code register is represented, in our imagination,
403 as a register holding a value that can be compared to zero.
404 In fact, the machine has already compared them and recorded the
405 results; but instructions that look at the condition code
406 pretend to be looking at the entire value and comparing it. */
407 DEF_RTL_EXPR(CC0, "cc0", "", RTX_OBJ)
408
409 /* ----------------------------------------------------------------------
410 Expressions for operators in an rtl pattern
411 ---------------------------------------------------------------------- */
412
413 /* if_then_else. This is used in representing ordinary
414 conditional jump instructions.
415 Operand:
416 0: condition
417 1: then expr
418 2: else expr */
419 DEF_RTL_EXPR(IF_THEN_ELSE, "if_then_else", "eee", RTX_TERNARY)
420
421 /* Comparison, produces a condition code result. */
422 DEF_RTL_EXPR(COMPARE, "compare", "ee", RTX_BIN_ARITH)
423
424 /* plus */
425 DEF_RTL_EXPR(PLUS, "plus", "ee", RTX_COMM_ARITH)
426
427 /* Operand 0 minus operand 1. */
428 DEF_RTL_EXPR(MINUS, "minus", "ee", RTX_BIN_ARITH)
429
430 /* Minus operand 0. */
431 DEF_RTL_EXPR(NEG, "neg", "e", RTX_UNARY)
432
433 DEF_RTL_EXPR(MULT, "mult", "ee", RTX_COMM_ARITH)
434
435 /* Operand 0 divided by operand 1. */
436 DEF_RTL_EXPR(DIV, "div", "ee", RTX_BIN_ARITH)
437 /* Remainder of operand 0 divided by operand 1. */
438 DEF_RTL_EXPR(MOD, "mod", "ee", RTX_BIN_ARITH)
439
440 /* Unsigned divide and remainder. */
441 DEF_RTL_EXPR(UDIV, "udiv", "ee", RTX_BIN_ARITH)
442 DEF_RTL_EXPR(UMOD, "umod", "ee", RTX_BIN_ARITH)
443
444 /* Bitwise operations. */
445 DEF_RTL_EXPR(AND, "and", "ee", RTX_COMM_ARITH)
446
447 DEF_RTL_EXPR(IOR, "ior", "ee", RTX_COMM_ARITH)
448
449 DEF_RTL_EXPR(XOR, "xor", "ee", RTX_COMM_ARITH)
450
451 DEF_RTL_EXPR(NOT, "not", "e", RTX_UNARY)
452
453 /* Operand:
454 0: value to be shifted.
455 1: number of bits. */
456 DEF_RTL_EXPR(ASHIFT, "ashift", "ee", RTX_BIN_ARITH) /* shift left */
457 DEF_RTL_EXPR(ROTATE, "rotate", "ee", RTX_BIN_ARITH) /* rotate left */
458 DEF_RTL_EXPR(ASHIFTRT, "ashiftrt", "ee", RTX_BIN_ARITH) /* arithmetic shift right */
459 DEF_RTL_EXPR(LSHIFTRT, "lshiftrt", "ee", RTX_BIN_ARITH) /* logical shift right */
460 DEF_RTL_EXPR(ROTATERT, "rotatert", "ee", RTX_BIN_ARITH) /* rotate right */
461
462 /* Minimum and maximum values of two operands. We need both signed and
463 unsigned forms. (We cannot use MIN for SMIN because it conflicts
464 with a macro of the same name.) */
465
466 DEF_RTL_EXPR(SMIN, "smin", "ee", RTX_COMM_ARITH)
467 DEF_RTL_EXPR(SMAX, "smax", "ee", RTX_COMM_ARITH)
468 DEF_RTL_EXPR(UMIN, "umin", "ee", RTX_COMM_ARITH)
469 DEF_RTL_EXPR(UMAX, "umax", "ee", RTX_COMM_ARITH)
470
471 /* These unary operations are used to represent incrementation
472 and decrementation as they occur in memory addresses.
473 The amount of increment or decrement are not represented
474 because they can be understood from the machine-mode of the
475 containing MEM. These operations exist in only two cases:
476 1. pushes onto the stack.
477 2. created automatically by the life_analysis pass in flow.c. */
478 DEF_RTL_EXPR(PRE_DEC, "pre_dec", "e", RTX_AUTOINC)
479 DEF_RTL_EXPR(PRE_INC, "pre_inc", "e", RTX_AUTOINC)
480 DEF_RTL_EXPR(POST_DEC, "post_dec", "e", RTX_AUTOINC)
481 DEF_RTL_EXPR(POST_INC, "post_inc", "e", RTX_AUTOINC)
482
483 /* These binary operations are used to represent generic address
484 side-effects in memory addresses, except for simple incrementation
485 or decrementation which use the above operations. They are
486 created automatically by the life_analysis pass in flow.c.
487 The first operand is a REG which is used as the address.
488 The second operand is an expression that is assigned to the
489 register, either before (PRE_MODIFY) or after (POST_MODIFY)
490 evaluating the address.
491 Currently, the compiler can only handle second operands of the
492 form (plus (reg) (reg)) and (plus (reg) (const_int)), where
493 the first operand of the PLUS has to be the same register as
494 the first operand of the *_MODIFY. */
495 DEF_RTL_EXPR(PRE_MODIFY, "pre_modify", "ee", RTX_AUTOINC)
496 DEF_RTL_EXPR(POST_MODIFY, "post_modify", "ee", RTX_AUTOINC)
497
498 /* Comparison operations. The ordered comparisons exist in two
499 flavors, signed and unsigned. */
500 DEF_RTL_EXPR(NE, "ne", "ee", RTX_COMM_COMPARE)
501 DEF_RTL_EXPR(EQ, "eq", "ee", RTX_COMM_COMPARE)
502 DEF_RTL_EXPR(GE, "ge", "ee", RTX_COMPARE)
503 DEF_RTL_EXPR(GT, "gt", "ee", RTX_COMPARE)
504 DEF_RTL_EXPR(LE, "le", "ee", RTX_COMPARE)
505 DEF_RTL_EXPR(LT, "lt", "ee", RTX_COMPARE)
506 DEF_RTL_EXPR(GEU, "geu", "ee", RTX_COMPARE)
507 DEF_RTL_EXPR(GTU, "gtu", "ee", RTX_COMPARE)
508 DEF_RTL_EXPR(LEU, "leu", "ee", RTX_COMPARE)
509 DEF_RTL_EXPR(LTU, "ltu", "ee", RTX_COMPARE)
510
511 /* Additional floating point unordered comparison flavors. */
512 DEF_RTL_EXPR(UNORDERED, "unordered", "ee", RTX_COMM_COMPARE)
513 DEF_RTL_EXPR(ORDERED, "ordered", "ee", RTX_COMM_COMPARE)
514
515 /* These are equivalent to unordered or ... */
516 DEF_RTL_EXPR(UNEQ, "uneq", "ee", RTX_COMM_COMPARE)
517 DEF_RTL_EXPR(UNGE, "unge", "ee", RTX_COMPARE)
518 DEF_RTL_EXPR(UNGT, "ungt", "ee", RTX_COMPARE)
519 DEF_RTL_EXPR(UNLE, "unle", "ee", RTX_COMPARE)
520 DEF_RTL_EXPR(UNLT, "unlt", "ee", RTX_COMPARE)
521
522 /* This is an ordered NE, ie !UNEQ, ie false for NaN. */
523 DEF_RTL_EXPR(LTGT, "ltgt", "ee", RTX_COMM_COMPARE)
524
525 /* Represents the result of sign-extending the sole operand.
526 The machine modes of the operand and of the SIGN_EXTEND expression
527 determine how much sign-extension is going on. */
528 DEF_RTL_EXPR(SIGN_EXTEND, "sign_extend", "e", RTX_UNARY)
529
530 /* Similar for zero-extension (such as unsigned short to int). */
531 DEF_RTL_EXPR(ZERO_EXTEND, "zero_extend", "e", RTX_UNARY)
532
533 /* Similar but here the operand has a wider mode. */
534 DEF_RTL_EXPR(TRUNCATE, "truncate", "e", RTX_UNARY)
535
536 /* Similar for extending floating-point values (such as SFmode to DFmode). */
537 DEF_RTL_EXPR(FLOAT_EXTEND, "float_extend", "e", RTX_UNARY)
538 DEF_RTL_EXPR(FLOAT_TRUNCATE, "float_truncate", "e", RTX_UNARY)
539
540 /* Conversion of fixed point operand to floating point value. */
541 DEF_RTL_EXPR(FLOAT, "float", "e", RTX_UNARY)
542
543 /* With fixed-point machine mode:
544 Conversion of floating point operand to fixed point value.
545 Value is defined only when the operand's value is an integer.
546 With floating-point machine mode (and operand with same mode):
547 Operand is rounded toward zero to produce an integer value
548 represented in floating point. */
549 DEF_RTL_EXPR(FIX, "fix", "e", RTX_UNARY)
550
551 /* Conversion of unsigned fixed point operand to floating point value. */
552 DEF_RTL_EXPR(UNSIGNED_FLOAT, "unsigned_float", "e", RTX_UNARY)
553
554 /* With fixed-point machine mode:
555 Conversion of floating point operand to *unsigned* fixed point value.
556 Value is defined only when the operand's value is an integer. */
557 DEF_RTL_EXPR(UNSIGNED_FIX, "unsigned_fix", "e", RTX_UNARY)
558
559 /* Absolute value */
560 DEF_RTL_EXPR(ABS, "abs", "e", RTX_UNARY)
561
562 /* Square root */
563 DEF_RTL_EXPR(SQRT, "sqrt", "e", RTX_UNARY)
564
565 /* Find first bit that is set.
566 Value is 1 + number of trailing zeros in the arg.,
567 or 0 if arg is 0. */
568 DEF_RTL_EXPR(FFS, "ffs", "e", RTX_UNARY)
569
570 /* Count leading zeros. */
571 DEF_RTL_EXPR(CLZ, "clz", "e", RTX_UNARY)
572
573 /* Count trailing zeros. */
574 DEF_RTL_EXPR(CTZ, "ctz", "e", RTX_UNARY)
575
576 /* Population count (number of 1 bits). */
577 DEF_RTL_EXPR(POPCOUNT, "popcount", "e", RTX_UNARY)
578
579 /* Population parity (number of 1 bits modulo 2). */
580 DEF_RTL_EXPR(PARITY, "parity", "e", RTX_UNARY)
581
582 /* Reference to a signed bit-field of specified size and position.
583 Operand 0 is the memory unit (usually SImode or QImode) which
584 contains the field's first bit. Operand 1 is the width, in bits.
585 Operand 2 is the number of bits in the memory unit before the
586 first bit of this field.
587 If BITS_BIG_ENDIAN is defined, the first bit is the msb and
588 operand 2 counts from the msb of the memory unit.
589 Otherwise, the first bit is the lsb and operand 2 counts from
590 the lsb of the memory unit.
591 This kind of expression can not appear as an lvalue in RTL. */
592 DEF_RTL_EXPR(SIGN_EXTRACT, "sign_extract", "eee", RTX_BITFIELD_OPS)
593
594 /* Similar for unsigned bit-field.
595 But note! This kind of expression _can_ appear as an lvalue. */
596 DEF_RTL_EXPR(ZERO_EXTRACT, "zero_extract", "eee", RTX_BITFIELD_OPS)
597
598 /* For RISC machines. These save memory when splitting insns. */
599
600 /* HIGH are the high-order bits of a constant expression. */
601 DEF_RTL_EXPR(HIGH, "high", "e", RTX_CONST_OBJ)
602
603 /* LO_SUM is the sum of a register and the low-order bits
604 of a constant expression. */
605 DEF_RTL_EXPR(LO_SUM, "lo_sum", "ee", RTX_OBJ)
606
607 /* Describes a merge operation between two vector values.
608 Operands 0 and 1 are the vectors to be merged, operand 2 is a bitmask
609 that specifies where the parts of the result are taken from. Set bits
610 indicate operand 0, clear bits indicate operand 1. The parts are defined
611 by the mode of the vectors. */
612 DEF_RTL_EXPR(VEC_MERGE, "vec_merge", "eee", RTX_TERNARY)
613
614 /* Describes an operation that selects parts of a vector.
615 Operands 0 is the source vector, operand 1 is a PARALLEL that contains
616 a CONST_INT for each of the subparts of the result vector, giving the
617 number of the source subpart that should be stored into it. */
618 DEF_RTL_EXPR(VEC_SELECT, "vec_select", "ee", RTX_BIN_ARITH)
619
620 /* Describes a vector concat operation. Operands 0 and 1 are the source
621 vectors, the result is a vector that is as long as operands 0 and 1
622 combined and is the concatenation of the two source vectors. */
623 DEF_RTL_EXPR(VEC_CONCAT, "vec_concat", "ee", RTX_BIN_ARITH)
624
625 /* Describes an operation that converts a small vector into a larger one by
626 duplicating the input values. The output vector mode must have the same
627 submodes as the input vector mode, and the number of output parts must be
628 an integer multiple of the number of input parts. */
629 DEF_RTL_EXPR(VEC_DUPLICATE, "vec_duplicate", "e", RTX_UNARY)
630
631 /* Addition with signed saturation */
632 DEF_RTL_EXPR(SS_PLUS, "ss_plus", "ee", RTX_COMM_ARITH)
633
634 /* Addition with unsigned saturation */
635 DEF_RTL_EXPR(US_PLUS, "us_plus", "ee", RTX_COMM_ARITH)
636
637 /* Operand 0 minus operand 1, with signed saturation. */
638 DEF_RTL_EXPR(SS_MINUS, "ss_minus", "ee", RTX_BIN_ARITH)
639
640 /* Operand 0 minus operand 1, with unsigned saturation. */
641 DEF_RTL_EXPR(US_MINUS, "us_minus", "ee", RTX_BIN_ARITH)
642
643 /* Signed saturating truncate. */
644 DEF_RTL_EXPR(SS_TRUNCATE, "ss_truncate", "e", RTX_UNARY)
645
646 /* Unsigned saturating truncate. */
647 DEF_RTL_EXPR(US_TRUNCATE, "us_truncate", "e", RTX_UNARY)
648
649 /* Information about the variable and its location. */
650 DEF_RTL_EXPR(VAR_LOCATION, "var_location", "te", RTX_EXTRA)
651
652 /* All expressions from this point forward appear only in machine
653 descriptions. */
654 #ifdef GENERATOR_FILE
655
656 /* Include a secondary machine-description file at this point. */
657 DEF_RTL_EXPR(INCLUDE, "include", "s", RTX_EXTRA)
658
659 /* Pattern-matching operators: */
660
661 /* Use the function named by the second arg (the string)
662 as a predicate; if matched, store the structure that was matched
663 in the operand table at index specified by the first arg (the integer).
664 If the second arg is the null string, the structure is just stored.
665
666 A third string argument indicates to the register allocator restrictions
667 on where the operand can be allocated.
668
669 If the target needs no restriction on any instruction this field should
670 be the null string.
671
672 The string is prepended by:
673 '=' to indicate the operand is only written to.
674 '+' to indicate the operand is both read and written to.
675
676 Each character in the string represents an allocable class for an operand.
677 'g' indicates the operand can be any valid class.
678 'i' indicates the operand can be immediate (in the instruction) data.
679 'r' indicates the operand can be in a register.
680 'm' indicates the operand can be in memory.
681 'o' a subset of the 'm' class. Those memory addressing modes that
682 can be offset at compile time (have a constant added to them).
683
684 Other characters indicate target dependent operand classes and
685 are described in each target's machine description.
686
687 For instructions with more than one operand, sets of classes can be
688 separated by a comma to indicate the appropriate multi-operand constraints.
689 There must be a 1 to 1 correspondence between these sets of classes in
690 all operands for an instruction.
691 */
692 DEF_RTL_EXPR(MATCH_OPERAND, "match_operand", "iss", RTX_MATCH)
693
694 /* Match a SCRATCH or a register. When used to generate rtl, a
695 SCRATCH is generated. As for MATCH_OPERAND, the mode specifies
696 the desired mode and the first argument is the operand number.
697 The second argument is the constraint. */
698 DEF_RTL_EXPR(MATCH_SCRATCH, "match_scratch", "is", RTX_MATCH)
699
700 /* Apply a predicate, AND match recursively the operands of the rtx.
701 Operand 0 is the operand-number, as in match_operand.
702 Operand 1 is a predicate to apply (as a string, a function name).
703 Operand 2 is a vector of expressions, each of which must match
704 one subexpression of the rtx this construct is matching. */
705 DEF_RTL_EXPR(MATCH_OPERATOR, "match_operator", "isE", RTX_MATCH)
706
707 /* Match a PARALLEL of arbitrary length. The predicate is applied
708 to the PARALLEL and the initial expressions in the PARALLEL are matched.
709 Operand 0 is the operand-number, as in match_operand.
710 Operand 1 is a predicate to apply to the PARALLEL.
711 Operand 2 is a vector of expressions, each of which must match the
712 corresponding element in the PARALLEL. */
713 DEF_RTL_EXPR(MATCH_PARALLEL, "match_parallel", "isE", RTX_MATCH)
714
715 /* Match only something equal to what is stored in the operand table
716 at the index specified by the argument. Use with MATCH_OPERAND. */
717 DEF_RTL_EXPR(MATCH_DUP, "match_dup", "i", RTX_MATCH)
718
719 /* Match only something equal to what is stored in the operand table
720 at the index specified by the argument. Use with MATCH_OPERATOR. */
721 DEF_RTL_EXPR(MATCH_OP_DUP, "match_op_dup", "iE", RTX_MATCH)
722
723 /* Match only something equal to what is stored in the operand table
724 at the index specified by the argument. Use with MATCH_PARALLEL. */
725 DEF_RTL_EXPR(MATCH_PAR_DUP, "match_par_dup", "iE", RTX_MATCH)
726
727 /* Appears only in define_predicate/define_special_predicate
728 expressions. Evaluates true only if the operand has an RTX code
729 from the set given by the argument (a comma-separated list). */
730 DEF_RTL_EXPR(MATCH_CODE, "match_code", "s", RTX_MATCH)
731
732 /* Appears only in define_predicate/define_special_predicate
733 expressions. The argument is a C expression to be injected at this
734 point in the predicate formula. */
735 DEF_RTL_EXPR(MATCH_TEST, "match_test", "s", RTX_MATCH)
736
737 /* Insn (and related) definitions. */
738
739 /* Definition of the pattern for one kind of instruction.
740 Operand:
741 0: names this instruction.
742 If the name is the null string, the instruction is in the
743 machine description just to be recognized, and will never be emitted by
744 the tree to rtl expander.
745 1: is the pattern.
746 2: is a string which is a C expression
747 giving an additional condition for recognizing this pattern.
748 A null string means no extra condition.
749 3: is the action to execute if this pattern is matched.
750 If this assembler code template starts with a * then it is a fragment of
751 C code to run to decide on a template to use. Otherwise, it is the
752 template to use.
753 4: optionally, a vector of attributes for this insn.
754 */
755 DEF_RTL_EXPR(DEFINE_INSN, "define_insn", "sEsTV", RTX_EXTRA)
756
757 /* Definition of a peephole optimization.
758 1st operand: vector of insn patterns to match
759 2nd operand: C expression that must be true
760 3rd operand: template or C code to produce assembler output.
761 4: optionally, a vector of attributes for this insn.
762
763 This form is deprecated; use define_peephole2 instead. */
764 DEF_RTL_EXPR(DEFINE_PEEPHOLE, "define_peephole", "EsTV", RTX_EXTRA)
765
766 /* Definition of a split operation.
767 1st operand: insn pattern to match
768 2nd operand: C expression that must be true
769 3rd operand: vector of insn patterns to place into a SEQUENCE
770 4th operand: optionally, some C code to execute before generating the
771 insns. This might, for example, create some RTX's and store them in
772 elements of `recog_data.operand' for use by the vector of
773 insn-patterns.
774 (`operands' is an alias here for `recog_data.operand'). */
775 DEF_RTL_EXPR(DEFINE_SPLIT, "define_split", "EsES", RTX_EXTRA)
776
777 /* Definition of an insn and associated split.
778 This is the concatenation, with a few modifications, of a define_insn
779 and a define_split which share the same pattern.
780 Operand:
781 0: names this instruction.
782 If the name is the null string, the instruction is in the
783 machine description just to be recognized, and will never be emitted by
784 the tree to rtl expander.
785 1: is the pattern.
786 2: is a string which is a C expression
787 giving an additional condition for recognizing this pattern.
788 A null string means no extra condition.
789 3: is the action to execute if this pattern is matched.
790 If this assembler code template starts with a * then it is a fragment of
791 C code to run to decide on a template to use. Otherwise, it is the
792 template to use.
793 4: C expression that must be true for split. This may start with "&&"
794 in which case the split condition is the logical and of the insn
795 condition and what follows the "&&" of this operand.
796 5: vector of insn patterns to place into a SEQUENCE
797 6: optionally, some C code to execute before generating the
798 insns. This might, for example, create some RTX's and store them in
799 elements of `recog_data.operand' for use by the vector of
800 insn-patterns.
801 (`operands' is an alias here for `recog_data.operand').
802 7: optionally, a vector of attributes for this insn. */
803 DEF_RTL_EXPR(DEFINE_INSN_AND_SPLIT, "define_insn_and_split", "sEsTsESV", RTX_EXTRA)
804
805 /* Definition of an RTL peephole operation.
806 Follows the same arguments as define_split. */
807 DEF_RTL_EXPR(DEFINE_PEEPHOLE2, "define_peephole2", "EsES", RTX_EXTRA)
808
809 /* Define how to generate multiple insns for a standard insn name.
810 1st operand: the insn name.
811 2nd operand: vector of insn-patterns.
812 Use match_operand to substitute an element of `recog_data.operand'.
813 3rd operand: C expression that must be true for this to be available.
814 This may not test any operands.
815 4th operand: Extra C code to execute before generating the insns.
816 This might, for example, create some RTX's and store them in
817 elements of `recog_data.operand' for use by the vector of
818 insn-patterns.
819 (`operands' is an alias here for `recog_data.operand'). */
820 DEF_RTL_EXPR(DEFINE_EXPAND, "define_expand", "sEss", RTX_EXTRA)
821
822 /* Define a requirement for delay slots.
823 1st operand: Condition involving insn attributes that, if true,
824 indicates that the insn requires the number of delay slots
825 shown.
826 2nd operand: Vector whose length is the three times the number of delay
827 slots required.
828 Each entry gives three conditions, each involving attributes.
829 The first must be true for an insn to occupy that delay slot
830 location. The second is true for all insns that can be
831 annulled if the branch is true and the third is true for all
832 insns that can be annulled if the branch is false.
833
834 Multiple DEFINE_DELAYs may be present. They indicate differing
835 requirements for delay slots. */
836 DEF_RTL_EXPR(DEFINE_DELAY, "define_delay", "eE", RTX_EXTRA)
837
838 /* Define attribute computation for `asm' instructions. */
839 DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES, "define_asm_attributes", "V", RTX_EXTRA)
840
841 /* Definition of a conditional execution meta operation. Automatically
842 generates new instances of DEFINE_INSN, selected by having attribute
843 "predicable" true. The new pattern will contain a COND_EXEC and the
844 predicate at top-level.
845
846 Operand:
847 0: The predicate pattern. The top-level form should match a
848 relational operator. Operands should have only one alternative.
849 1: A C expression giving an additional condition for recognizing
850 the generated pattern.
851 2: A template or C code to produce assembler output. */
852 DEF_RTL_EXPR(DEFINE_COND_EXEC, "define_cond_exec", "Ess", RTX_EXTRA)
853
854 /* Definition of an operand predicate. The difference between
855 DEFINE_PREDICATE and DEFINE_SPECIAL_PREDICATE is that genrecog will
856 not warn about a match_operand with no mode if it has a predicate
857 defined with DEFINE_SPECIAL_PREDICATE.
858
859 Operand:
860 0: The name of the predicate.
861 1: A boolean expression which computes whether or not the predicate
862 matches. This expression can use IOR, AND, NOT, MATCH_OPERAND,
863 MATCH_CODE, and MATCH_TEST. It must be specific enough that genrecog
864 can calculate the set of RTX codes that can possibly match.
865 2: A C function body which must return true for the predicate to match.
866 Optional. Use this when the test is too complicated to fit into a
867 match_test expression. */
868 DEF_RTL_EXPR(DEFINE_PREDICATE, "define_predicate", "ses", RTX_EXTRA)
869 DEF_RTL_EXPR(DEFINE_SPECIAL_PREDICATE, "define_special_predicate", "ses", RTX_EXTRA)
870
871 /* Constructions for CPU pipeline description described by NDFAs. */
872
873 /* (define_cpu_unit string [string]) describes cpu functional
874 units (separated by comma).
875
876 1st operand: Names of cpu functional units.
877 2nd operand: Name of automaton (see comments for DEFINE_AUTOMATON).
878
879 All define_reservations, define_cpu_units, and
880 define_query_cpu_units should have unique names which may not be
881 "nothing". */
882 DEF_RTL_EXPR(DEFINE_CPU_UNIT, "define_cpu_unit", "sS", RTX_EXTRA)
883
884 /* (define_query_cpu_unit string [string]) describes cpu functional
885 units analogously to define_cpu_unit. The reservation of such
886 units can be queried for automaton state. */
887 DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT, "define_query_cpu_unit", "sS", RTX_EXTRA)
888
889 /* (exclusion_set string string) means that each CPU functional unit
890 in the first string can not be reserved simultaneously with any
891 unit whose name is in the second string and vise versa. CPU units
892 in the string are separated by commas. For example, it is useful
893 for description CPU with fully pipelined floating point functional
894 unit which can execute simultaneously only single floating point
895 insns or only double floating point insns. All CPU functional
896 units in a set should belong to the same automaton. */
897 DEF_RTL_EXPR(EXCLUSION_SET, "exclusion_set", "ss", RTX_EXTRA)
898
899 /* (presence_set string string) means that each CPU functional unit in
900 the first string can not be reserved unless at least one of pattern
901 of units whose names are in the second string is reserved. This is
902 an asymmetric relation. CPU units or unit patterns in the strings
903 are separated by commas. Pattern is one unit name or unit names
904 separated by white-spaces.
905
906 For example, it is useful for description that slot1 is reserved
907 after slot0 reservation for a VLIW processor. We could describe it
908 by the following construction
909
910 (presence_set "slot1" "slot0")
911
912 Or slot1 is reserved only after slot0 and unit b0 reservation. In
913 this case we could write
914
915 (presence_set "slot1" "slot0 b0")
916
917 All CPU functional units in a set should belong to the same
918 automaton. */
919 DEF_RTL_EXPR(PRESENCE_SET, "presence_set", "ss", RTX_EXTRA)
920
921 /* (final_presence_set string string) is analogous to `presence_set'.
922 The difference between them is when checking is done. When an
923 instruction is issued in given automaton state reflecting all
924 current and planned unit reservations, the automaton state is
925 changed. The first state is a source state, the second one is a
926 result state. Checking for `presence_set' is done on the source
927 state reservation, checking for `final_presence_set' is done on the
928 result reservation. This construction is useful to describe a
929 reservation which is actually two subsequent reservations. For
930 example, if we use
931
932 (presence_set "slot1" "slot0")
933
934 the following insn will be never issued (because slot1 requires
935 slot0 which is absent in the source state).
936
937 (define_reservation "insn_and_nop" "slot0 + slot1")
938
939 but it can be issued if we use analogous `final_presence_set'. */
940 DEF_RTL_EXPR(FINAL_PRESENCE_SET, "final_presence_set", "ss", RTX_EXTRA)
941
942 /* (absence_set string string) means that each CPU functional unit in
943 the first string can be reserved only if each pattern of units
944 whose names are in the second string is not reserved. This is an
945 asymmetric relation (actually exclusion set is analogous to this
946 one but it is symmetric). CPU units or unit patterns in the string
947 are separated by commas. Pattern is one unit name or unit names
948 separated by white-spaces.
949
950 For example, it is useful for description that slot0 can not be
951 reserved after slot1 or slot2 reservation for a VLIW processor. We
952 could describe it by the following construction
953
954 (absence_set "slot2" "slot0, slot1")
955
956 Or slot2 can not be reserved if slot0 and unit b0 are reserved or
957 slot1 and unit b1 are reserved . In this case we could write
958
959 (absence_set "slot2" "slot0 b0, slot1 b1")
960
961 All CPU functional units in a set should to belong the same
962 automaton. */
963 DEF_RTL_EXPR(ABSENCE_SET, "absence_set", "ss", RTX_EXTRA)
964
965 /* (final_absence_set string string) is analogous to `absence_set' but
966 checking is done on the result (state) reservation. See comments
967 for `final_presence_set'. */
968 DEF_RTL_EXPR(FINAL_ABSENCE_SET, "final_absence_set", "ss", RTX_EXTRA)
969
970 /* (define_bypass number out_insn_names in_insn_names) names bypass
971 with given latency (the first number) from insns given by the first
972 string (see define_insn_reservation) into insns given by the second
973 string. Insn names in the strings are separated by commas. The
974 third operand is optional name of function which is additional
975 guard for the bypass. The function will get the two insns as
976 parameters. If the function returns zero the bypass will be
977 ignored for this case. Additional guard is necessary to recognize
978 complicated bypasses, e.g. when consumer is load address. */
979 DEF_RTL_EXPR(DEFINE_BYPASS, "define_bypass", "issS", RTX_EXTRA)
980
981 /* (define_automaton string) describes names of automata generated and
982 used for pipeline hazards recognition. The names are separated by
983 comma. Actually it is possibly to generate the single automaton
984 but unfortunately it can be very large. If we use more one
985 automata, the summary size of the automata usually is less than the
986 single one. The automaton name is used in define_cpu_unit and
987 define_query_cpu_unit. All automata should have unique names. */
988 DEF_RTL_EXPR(DEFINE_AUTOMATON, "define_automaton", "s", RTX_EXTRA)
989
990 /* (automata_option string) describes option for generation of
991 automata. Currently there are the following options:
992
993 o "no-minimization" which makes no minimization of automata. This
994 is only worth to do when we are debugging the description and
995 need to look more accurately at reservations of states.
996
997 o "time" which means printing additional time statistics about
998 generation of automata.
999
1000 o "v" which means generation of file describing the result
1001 automata. The file has suffix `.dfa' and can be used for the
1002 description verification and debugging.
1003
1004 o "w" which means generation of warning instead of error for
1005 non-critical errors.
1006
1007 o "ndfa" which makes nondeterministic finite state automata.
1008
1009 o "progress" which means output of a progress bar showing how many
1010 states were generated so far for automaton being processed. */
1011 DEF_RTL_EXPR(AUTOMATA_OPTION, "automata_option", "s", RTX_EXTRA)
1012
1013 /* (define_reservation string string) names reservation (the first
1014 string) of cpu functional units (the 2nd string). Sometimes unit
1015 reservations for different insns contain common parts. In such
1016 case, you can describe common part and use its name (the 1st
1017 parameter) in regular expression in define_insn_reservation. All
1018 define_reservations, define_cpu_units, and define_query_cpu_units
1019 should have unique names which may not be "nothing". */
1020 DEF_RTL_EXPR(DEFINE_RESERVATION, "define_reservation", "ss", RTX_EXTRA)
1021
1022 /* (define_insn_reservation name default_latency condition regexpr)
1023 describes reservation of cpu functional units (the 3nd operand) for
1024 instruction which is selected by the condition (the 2nd parameter).
1025 The first parameter is used for output of debugging information.
1026 The reservations are described by a regular expression according
1027 the following syntax:
1028
1029 regexp = regexp "," oneof
1030 | oneof
1031
1032 oneof = oneof "|" allof
1033 | allof
1034
1035 allof = allof "+" repeat
1036 | repeat
1037
1038 repeat = element "*" number
1039 | element
1040
1041 element = cpu_function_unit_name
1042 | reservation_name
1043 | result_name
1044 | "nothing"
1045 | "(" regexp ")"
1046
1047 1. "," is used for describing start of the next cycle in
1048 reservation.
1049
1050 2. "|" is used for describing the reservation described by the
1051 first regular expression *or* the reservation described by the
1052 second regular expression *or* etc.
1053
1054 3. "+" is used for describing the reservation described by the
1055 first regular expression *and* the reservation described by the
1056 second regular expression *and* etc.
1057
1058 4. "*" is used for convenience and simply means sequence in
1059 which the regular expression are repeated NUMBER times with
1060 cycle advancing (see ",").
1061
1062 5. cpu functional unit name which means its reservation.
1063
1064 6. reservation name -- see define_reservation.
1065
1066 7. string "nothing" means no units reservation. */
1067
1068 DEF_RTL_EXPR(DEFINE_INSN_RESERVATION, "define_insn_reservation", "sies", RTX_EXTRA)
1069
1070 /* Expressions used for insn attributes. */
1071
1072 /* Definition of an insn attribute.
1073 1st operand: name of the attribute
1074 2nd operand: comma-separated list of possible attribute values
1075 3rd operand: expression for the default value of the attribute. */
1076 DEF_RTL_EXPR(DEFINE_ATTR, "define_attr", "sse", RTX_EXTRA)
1077
1078 /* Marker for the name of an attribute. */
1079 DEF_RTL_EXPR(ATTR, "attr", "s", RTX_EXTRA)
1080
1081 /* For use in the last (optional) operand of DEFINE_INSN or DEFINE_PEEPHOLE and
1082 in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that
1083 pattern.
1084
1085 (set_attr "name" "value") is equivalent to
1086 (set (attr "name") (const_string "value")) */
1087 DEF_RTL_EXPR(SET_ATTR, "set_attr", "ss", RTX_EXTRA)
1088
1089 /* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE, this can be used to
1090 specify that attribute values are to be assigned according to the
1091 alternative matched.
1092
1093 The following three expressions are equivalent:
1094
1095 (set (attr "att") (cond [(eq_attrq "alternative" "1") (const_string "a1")
1096 (eq_attrq "alternative" "2") (const_string "a2")]
1097 (const_string "a3")))
1098 (set_attr_alternative "att" [(const_string "a1") (const_string "a2")
1099 (const_string "a3")])
1100 (set_attr "att" "a1,a2,a3")
1101 */
1102 DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE, "set_attr_alternative", "sE", RTX_EXTRA)
1103
1104 /* A conditional expression true if the value of the specified attribute of
1105 the current insn equals the specified value. The first operand is the
1106 attribute name and the second is the comparison value. */
1107 DEF_RTL_EXPR(EQ_ATTR, "eq_attr", "ss", RTX_EXTRA)
1108
1109 /* A special case of the above representing a set of alternatives. The first
1110 operand is bitmap of the set, the second one is the default value. */
1111 DEF_RTL_EXPR(EQ_ATTR_ALT, "eq_attr_alt", "ii", RTX_EXTRA)
1112
1113 /* A conditional expression which is true if the specified flag is
1114 true for the insn being scheduled in reorg.
1115
1116 genattr.c defines the following flags which can be tested by
1117 (attr_flag "foo") expressions in eligible_for_delay.
1118
1119 forward, backward, very_likely, likely, very_unlikely, and unlikely. */
1120
1121 DEF_RTL_EXPR (ATTR_FLAG, "attr_flag", "s", RTX_EXTRA)
1122
1123 /* General conditional. The first operand is a vector composed of pairs of
1124 expressions. The first element of each pair is evaluated, in turn.
1125 The value of the conditional is the second expression of the first pair
1126 whose first expression evaluates nonzero. If none of the expressions is
1127 true, the second operand will be used as the value of the conditional. */
1128 DEF_RTL_EXPR(COND, "cond", "Ee", RTX_EXTRA)
1129
1130 #endif /* GENERATOR_FILE */
1131
1132 /*
1133 Local variables:
1134 mode:c
1135 End:
1136 */