rtl.def (LABEL_REF): Remove the field for LABEL_NEXTREF.
[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 2005
6 Free Software Foundation, Inc.
7
8 This file is part of GCC.
9
10 GCC is free software; you can redistribute it and/or modify it under
11 the terms of the GNU General Public License as published by the Free
12 Software Foundation; either version 2, or (at your option) any later
13 version.
14
15 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
16 WARRANTY; without even the implied warranty of MERCHANTABILITY or
17 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 for more details.
19
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING. If not, write to the Free
22 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
23 02110-1301, USA. */
24
25
26 /* Expression definitions and descriptions for all targets are in this file.
27 Some will not be used for some targets.
28
29 The fields in the cpp macro call "DEF_RTL_EXPR()"
30 are used to create declarations in the C source of the compiler.
31
32 The fields are:
33
34 1. The internal name of the rtx used in the C source.
35 It is a tag in the enumeration "enum rtx_code" defined in "rtl.h".
36 By convention these are in UPPER_CASE.
37
38 2. The name of the rtx in the external ASCII format read by
39 read_rtx(), and printed by print_rtx().
40 These names are stored in rtx_name[].
41 By convention these are the internal (field 1) names in lower_case.
42
43 3. The print format, and type of each rtx->u.fld[] (field) in this rtx.
44 These formats are stored in rtx_format[].
45 The meaning of the formats is documented in front of this array in rtl.c
46
47 4. The class of the rtx. These are stored in rtx_class and are accessed
48 via the GET_RTX_CLASS macro. They are defined as follows:
49
50 RTX_CONST_OBJ
51 an rtx code that can be used to represent a constant object
52 (e.g, CONST_INT)
53 RTX_OBJ
54 an rtx code that can be used to represent an object (e.g, REG, MEM)
55 RTX_COMPARE
56 an rtx code for a comparison (e.g, LT, GT)
57 RTX_COMM_COMPARE
58 an rtx code for a commutative comparison (e.g, EQ, NE, ORDERED)
59 RTX_UNARY
60 an rtx code for a unary arithmetic expression (e.g, NEG, NOT)
61 RTX_COMM_ARITH
62 an rtx code for a commutative binary operation (e.g,, PLUS, MULT)
63 RTX_TERNARY
64 an rtx code for a non-bitfield three input operation (IF_THEN_ELSE)
65 RTX_BIN_ARITH
66 an rtx code for a non-commutative binary operation (e.g., MINUS, DIV)
67 RTX_BITFIELD_OPS
68 an rtx code for a bit-field operation (ZERO_EXTRACT, SIGN_EXTRACT)
69 RTX_INSN
70 an rtx code for a machine insn (INSN, JUMP_INSN, CALL_INSN)
71 RTX_MATCH
72 an rtx code for something that matches in insns (e.g, MATCH_DUP)
73 RTX_AUTOINC
74 an rtx code for autoincrement addressing modes (e.g. POST_DEC)
75 RTX_EXTRA
76 everything else
77
78 All of the expressions that appear only in machine descriptions,
79 not in RTL used by the compiler itself, are at the end of the file. */
80
81 /* Unknown, or no such operation; the enumeration constant should have
82 value zero. */
83 DEF_RTL_EXPR(UNKNOWN, "UnKnown", "*", RTX_EXTRA)
84
85 /* ---------------------------------------------------------------------
86 Expressions used in constructing lists.
87 --------------------------------------------------------------------- */
88
89 /* a linked list of expressions */
90 DEF_RTL_EXPR(EXPR_LIST, "expr_list", "ee", RTX_EXTRA)
91
92 /* a linked list of instructions.
93 The insns are represented in print by their uids. */
94 DEF_RTL_EXPR(INSN_LIST, "insn_list", "ue", RTX_EXTRA)
95
96 /* SEQUENCE appears in the result of a `gen_...' function
97 for a DEFINE_EXPAND that wants to make several insns.
98 Its elements are the bodies of the insns that should be made.
99 `emit_insn' takes the SEQUENCE apart and makes separate insns. */
100 DEF_RTL_EXPR(SEQUENCE, "sequence", "E", RTX_EXTRA)
101
102 /* Refers to the address of its argument. This is only used in alias.c. */
103 DEF_RTL_EXPR(ADDRESS, "address", "e", RTX_MATCH)
104
105 /* ----------------------------------------------------------------------
106 Expression types used for things in the instruction chain.
107
108 All formats must start with "iuu" to handle the chain.
109 Each insn expression holds an rtl instruction and its semantics
110 during back-end processing.
111 See macros's in "rtl.h" for the meaning of each rtx->u.fld[].
112
113 ---------------------------------------------------------------------- */
114
115 /* An instruction that cannot jump. */
116 DEF_RTL_EXPR(INSN, "insn", "iuuBieiee", RTX_INSN)
117
118 /* An instruction that can possibly jump.
119 Fields ( rtx->u.fld[] ) have exact same meaning as INSN's. */
120 DEF_RTL_EXPR(JUMP_INSN, "jump_insn", "iuuBieiee0", RTX_INSN)
121
122 /* An instruction that can possibly call a subroutine
123 but which will not change which instruction comes next
124 in the current function.
125 Field ( rtx->u.fld[9] ) is CALL_INSN_FUNCTION_USAGE.
126 All other fields ( rtx->u.fld[] ) have exact same meaning as INSN's. */
127 DEF_RTL_EXPR(CALL_INSN, "call_insn", "iuuBieieee", RTX_INSN)
128
129 /* A marker that indicates that control will not flow through. */
130 DEF_RTL_EXPR(BARRIER, "barrier", "iuu000000", RTX_EXTRA)
131
132 /* Holds a label that is followed by instructions.
133 Operand:
134 4: is used in jump.c for the use-count of the label.
135 5: is used in flow.c to point to the chain of label_ref's to this label.
136 6: is a number that is unique in the entire compilation.
137 7: is the user-given name of the label, if any. */
138 DEF_RTL_EXPR(CODE_LABEL, "code_label", "iuuB00is", RTX_EXTRA)
139
140 #ifdef USE_MAPPED_LOCATION
141 /* Say where in the code a source line starts, for symbol table's sake.
142 Operand:
143 4: unused if line number > 0, note-specific data otherwise.
144 5: line number if > 0, enum note_insn otherwise.
145 6: CODE_LABEL_NUMBER if line number == NOTE_INSN_DELETED_LABEL. */
146 #else
147 /* Say where in the code a source line starts, for symbol table's sake.
148 Operand:
149 4: filename, if line number > 0, note-specific data otherwise.
150 5: line number if > 0, enum note_insn otherwise.
151 6: unique number if line number == note_insn_deleted_label. */
152 #endif
153 DEF_RTL_EXPR(NOTE, "note", "iuuB0ni", RTX_EXTRA)
154
155 /* ----------------------------------------------------------------------
156 Top level constituents of INSN, JUMP_INSN and CALL_INSN.
157 ---------------------------------------------------------------------- */
158
159 /* Conditionally execute code.
160 Operand 0 is the condition that if true, the code is executed.
161 Operand 1 is the code to be executed (typically a SET).
162
163 Semantics are that there are no side effects if the condition
164 is false. This pattern is created automatically by the if_convert
165 pass run after reload or by target-specific splitters. */
166 DEF_RTL_EXPR(COND_EXEC, "cond_exec", "ee", RTX_EXTRA)
167
168 /* Several operations to be done in parallel (perhaps under COND_EXEC). */
169 DEF_RTL_EXPR(PARALLEL, "parallel", "E", RTX_EXTRA)
170
171 /* A string that is passed through to the assembler as input.
172 One can obviously pass comments through by using the
173 assembler comment syntax.
174 These occur in an insn all by themselves as the PATTERN.
175 They also appear inside an ASM_OPERANDS
176 as a convenient way to hold a string. */
177 DEF_RTL_EXPR(ASM_INPUT, "asm_input", "s", RTX_EXTRA)
178
179 #ifdef USE_MAPPED_LOCATION
180 /* An assembler instruction with operands.
181 1st operand is the instruction template.
182 2nd operand is the constraint for the output.
183 3rd operand is the number of the output this expression refers to.
184 When an insn stores more than one value, a separate ASM_OPERANDS
185 is made for each output; this integer distinguishes them.
186 4th is a vector of values of input operands.
187 5th is a vector of modes and constraints for the input operands.
188 Each element is an ASM_INPUT containing a constraint string
189 and whose mode indicates the mode of the input operand.
190 6th is the source line number. */
191 DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEi", RTX_EXTRA)
192 #else
193 /* An assembler instruction with operands.
194 1st operand is the instruction template.
195 2nd operand is the constraint for the output.
196 3rd operand is the number of the output this expression refers to.
197 When an insn stores more than one value, a separate ASM_OPERANDS
198 is made for each output; this integer distinguishes them.
199 4th is a vector of values of input operands.
200 5th is a vector of modes and constraints for the input operands.
201 Each element is an ASM_INPUT containing a constraint string
202 and whose mode indicates the mode of the input operand.
203 6th is the name of the containing source file.
204 7th is the source line number. */
205 DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEsi", RTX_EXTRA)
206 #endif
207
208 /* A machine-specific operation.
209 1st operand is a vector of operands being used by the operation so that
210 any needed reloads can be done.
211 2nd operand is a unique value saying which of a number of machine-specific
212 operations is to be performed.
213 (Note that the vector must be the first operand because of the way that
214 genrecog.c record positions within an insn.)
215 This can occur all by itself in a PATTERN, as a component of a PARALLEL,
216 or inside an expression. */
217 DEF_RTL_EXPR(UNSPEC, "unspec", "Ei", RTX_EXTRA)
218
219 /* Similar, but a volatile operation and one which may trap. */
220 DEF_RTL_EXPR(UNSPEC_VOLATILE, "unspec_volatile", "Ei", RTX_EXTRA)
221
222 /* Vector of addresses, stored as full words. */
223 /* Each element is a LABEL_REF to a CODE_LABEL whose address we want. */
224 DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", RTX_EXTRA)
225
226 /* Vector of address differences X0 - BASE, X1 - BASE, ...
227 First operand is BASE; the vector contains the X's.
228 The machine mode of this rtx says how much space to leave
229 for each difference and is adjusted by branch shortening if
230 CASE_VECTOR_SHORTEN_MODE is defined.
231 The third and fourth operands store the target labels with the
232 minimum and maximum addresses respectively.
233 The fifth operand stores flags for use by branch shortening.
234 Set at the start of shorten_branches:
235 min_align: the minimum alignment for any of the target labels.
236 base_after_vec: true iff BASE is after the ADDR_DIFF_VEC.
237 min_after_vec: true iff minimum addr target label is after the ADDR_DIFF_VEC.
238 max_after_vec: true iff maximum addr target label is after the ADDR_DIFF_VEC.
239 min_after_base: true iff minimum address target label is after BASE.
240 max_after_base: true iff maximum address target label is after BASE.
241 Set by the actual branch shortening process:
242 offset_unsigned: true iff offsets have to be treated as unsigned.
243 scale: scaling that is necessary to make offsets fit into the mode.
244
245 The third, fourth and fifth operands are only valid when
246 CASE_VECTOR_SHORTEN_MODE is defined, and only in an optimizing
247 compilations. */
248
249 DEF_RTL_EXPR(ADDR_DIFF_VEC, "addr_diff_vec", "eEee0", RTX_EXTRA)
250
251 /* Memory prefetch, with attributes supported on some targets.
252 Operand 1 is the address of the memory to fetch.
253 Operand 2 is 1 for a write access, 0 otherwise.
254 Operand 3 is the level of temporal locality; 0 means there is no
255 temporal locality and 1, 2, and 3 are for increasing levels of temporal
256 locality.
257
258 The attributes specified by operands 2 and 3 are ignored for targets
259 whose prefetch instructions do not support them. */
260 DEF_RTL_EXPR(PREFETCH, "prefetch", "eee", RTX_EXTRA)
261
262 /* ----------------------------------------------------------------------
263 At the top level of an instruction (perhaps under PARALLEL).
264 ---------------------------------------------------------------------- */
265
266 /* Assignment.
267 Operand 1 is the location (REG, MEM, PC, CC0 or whatever) assigned to.
268 Operand 2 is the value stored there.
269 ALL assignment must use SET.
270 Instructions that do multiple assignments must use multiple SET,
271 under PARALLEL. */
272 DEF_RTL_EXPR(SET, "set", "ee", RTX_EXTRA)
273
274 /* Indicate something is used in a way that we don't want to explain.
275 For example, subroutine calls will use the register
276 in which the static chain is passed. */
277 DEF_RTL_EXPR(USE, "use", "e", RTX_EXTRA)
278
279 /* Indicate something is clobbered in a way that we don't want to explain.
280 For example, subroutine calls will clobber some physical registers
281 (the ones that are by convention not saved). */
282 DEF_RTL_EXPR(CLOBBER, "clobber", "e", RTX_EXTRA)
283
284 /* Call a subroutine.
285 Operand 1 is the address to call.
286 Operand 2 is the number of arguments. */
287
288 DEF_RTL_EXPR(CALL, "call", "ee", RTX_EXTRA)
289
290 /* Return from a subroutine. */
291
292 DEF_RTL_EXPR(RETURN, "return", "", RTX_EXTRA)
293
294 /* Conditional trap.
295 Operand 1 is the condition.
296 Operand 2 is the trap code.
297 For an unconditional trap, make the condition (const_int 1). */
298 DEF_RTL_EXPR(TRAP_IF, "trap_if", "ee", RTX_EXTRA)
299
300 /* Placeholder for _Unwind_Resume before we know if a function call
301 or a branch is needed. Operand 1 is the exception region from
302 which control is flowing. */
303 DEF_RTL_EXPR(RESX, "resx", "i", RTX_EXTRA)
304
305 /* ----------------------------------------------------------------------
306 Primitive values for use in expressions.
307 ---------------------------------------------------------------------- */
308
309 /* numeric integer constant */
310 DEF_RTL_EXPR(CONST_INT, "const_int", "w", RTX_CONST_OBJ)
311
312 /* numeric floating point constant.
313 Operands hold the value. They are all 'w' and there may be from 2 to 6;
314 see real.h. */
315 DEF_RTL_EXPR(CONST_DOUBLE, "const_double", CONST_DOUBLE_FORMAT, RTX_CONST_OBJ)
316
317 /* Describes a vector constant. */
318 DEF_RTL_EXPR(CONST_VECTOR, "const_vector", "E", RTX_CONST_OBJ)
319
320 /* String constant. Used for attributes in machine descriptions and
321 for special cases in DWARF2 debug output. NOT used for source-
322 language string constants. */
323 DEF_RTL_EXPR(CONST_STRING, "const_string", "s", RTX_OBJ)
324
325 /* This is used to encapsulate an expression whose value is constant
326 (such as the sum of a SYMBOL_REF and a CONST_INT) so that it will be
327 recognized as a constant operand rather than by arithmetic instructions. */
328
329 DEF_RTL_EXPR(CONST, "const", "e", RTX_CONST_OBJ)
330
331 /* program counter. Ordinary jumps are represented
332 by a SET whose first operand is (PC). */
333 DEF_RTL_EXPR(PC, "pc", "", RTX_OBJ)
334
335 /* Used in the cselib routines to describe a value. Objects of this
336 kind are only allocated in cselib.c, in an alloc pool instead of
337 in GC memory. The only operand of a VALUE is a cselib_val_struct. */
338 DEF_RTL_EXPR(VALUE, "value", "0", RTX_OBJ)
339
340 /* A register. The "operand" is the register number, accessed with
341 the REGNO macro. If this number is less than FIRST_PSEUDO_REGISTER
342 than a hardware register is being referred to. The second operand
343 holds the original register number - this will be different for a
344 pseudo register that got turned into a hard register. The third
345 operand points to a reg_attrs structure.
346 This rtx needs to have as many (or more) fields as a MEM, since we
347 can change REG rtx's into MEMs during reload. */
348 DEF_RTL_EXPR(REG, "reg", "i00", RTX_OBJ)
349
350 /* A scratch register. This represents a register used only within a
351 single insn. It will be turned into a REG during register allocation
352 or reload unless the constraint indicates that the register won't be
353 needed, in which case it can remain a SCRATCH. This code is
354 marked as having one operand so it can be turned into a REG. */
355 DEF_RTL_EXPR(SCRATCH, "scratch", "0", RTX_OBJ)
356
357 /* One word of a multi-word value.
358 The first operand is the complete value; the second says which word.
359 The WORDS_BIG_ENDIAN flag controls whether word number 0
360 (as numbered in a SUBREG) is the most or least significant word.
361
362 This is also used to refer to a value in a different machine mode.
363 For example, it can be used to refer to a SImode value as if it were
364 Qimode, or vice versa. Then the word number is always 0. */
365 DEF_RTL_EXPR(SUBREG, "subreg", "ei", RTX_EXTRA)
366
367 /* This one-argument rtx is used for move instructions
368 that are guaranteed to alter only the low part of a destination.
369 Thus, (SET (SUBREG:HI (REG...)) (MEM:HI ...))
370 has an unspecified effect on the high part of REG,
371 but (SET (STRICT_LOW_PART (SUBREG:HI (REG...))) (MEM:HI ...))
372 is guaranteed to alter only the bits of REG that are in HImode.
373
374 The actual instruction used is probably the same in both cases,
375 but the register constraints may be tighter when STRICT_LOW_PART
376 is in use. */
377
378 DEF_RTL_EXPR(STRICT_LOW_PART, "strict_low_part", "e", RTX_EXTRA)
379
380 /* (CONCAT a b) represents the virtual concatenation of a and b
381 to make a value that has as many bits as a and b put together.
382 This is used for complex values. Normally it appears only
383 in DECL_RTLs and during RTL generation, but not in the insn chain. */
384 DEF_RTL_EXPR(CONCAT, "concat", "ee", RTX_OBJ)
385
386 /* A memory location; operand is the address. The second operand is the
387 alias set to which this MEM belongs. We use `0' instead of `w' for this
388 field so that the field need not be specified in machine descriptions. */
389 DEF_RTL_EXPR(MEM, "mem", "e0", RTX_OBJ)
390
391 /* Reference to an assembler label in the code for this function.
392 The operand is a CODE_LABEL found in the insn chain. */
393 DEF_RTL_EXPR(LABEL_REF, "label_ref", "u", 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 DEF_RTL_EXPR(IOR, "ior", "ee", RTX_COMM_ARITH)
447 DEF_RTL_EXPR(XOR, "xor", "ee", RTX_COMM_ARITH)
448 DEF_RTL_EXPR(NOT, "not", "e", RTX_UNARY)
449
450 /* Operand:
451 0: value to be shifted.
452 1: number of bits. */
453 DEF_RTL_EXPR(ASHIFT, "ashift", "ee", RTX_BIN_ARITH) /* shift left */
454 DEF_RTL_EXPR(ROTATE, "rotate", "ee", RTX_BIN_ARITH) /* rotate left */
455 DEF_RTL_EXPR(ASHIFTRT, "ashiftrt", "ee", RTX_BIN_ARITH) /* arithmetic shift right */
456 DEF_RTL_EXPR(LSHIFTRT, "lshiftrt", "ee", RTX_BIN_ARITH) /* logical shift right */
457 DEF_RTL_EXPR(ROTATERT, "rotatert", "ee", RTX_BIN_ARITH) /* rotate right */
458
459 /* Minimum and maximum values of two operands. We need both signed and
460 unsigned forms. (We cannot use MIN for SMIN because it conflicts
461 with a macro of the same name.) The signed variants should be used
462 with floating point. Further, if both operands are zeros, or if either
463 operand is NaN, then it is unspecified which of the two operands is
464 returned as the result. */
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). If the
730 second argument is present and nonempty, it is a sequence of digits
731 and/or letters which indicates the subexpression to test, using the
732 same syntax as genextract/genrecog's location strings: 0-9 for
733 XEXP (op, n), a-z for XVECEXP (op, 0, n); each character applies to
734 the result of the one before it. */
735 DEF_RTL_EXPR(MATCH_CODE, "match_code", "ss", RTX_MATCH)
736
737 /* Appears only in define_predicate/define_special_predicate
738 expressions. The argument is a C expression to be injected at this
739 point in the predicate formula. */
740 DEF_RTL_EXPR(MATCH_TEST, "match_test", "s", RTX_MATCH)
741
742 /* Insn (and related) definitions. */
743
744 /* Definition of the pattern for one kind of instruction.
745 Operand:
746 0: names this instruction.
747 If the name is the null string, the instruction is in the
748 machine description just to be recognized, and will never be emitted by
749 the tree to rtl expander.
750 1: is the pattern.
751 2: is a string which is a C expression
752 giving an additional condition for recognizing this pattern.
753 A null string means no extra condition.
754 3: is the action to execute if this pattern is matched.
755 If this assembler code template starts with a * then it is a fragment of
756 C code to run to decide on a template to use. Otherwise, it is the
757 template to use.
758 4: optionally, a vector of attributes for this insn.
759 */
760 DEF_RTL_EXPR(DEFINE_INSN, "define_insn", "sEsTV", RTX_EXTRA)
761
762 /* Definition of a peephole optimization.
763 1st operand: vector of insn patterns to match
764 2nd operand: C expression that must be true
765 3rd operand: template or C code to produce assembler output.
766 4: optionally, a vector of attributes for this insn.
767
768 This form is deprecated; use define_peephole2 instead. */
769 DEF_RTL_EXPR(DEFINE_PEEPHOLE, "define_peephole", "EsTV", RTX_EXTRA)
770
771 /* Definition of a split operation.
772 1st operand: insn pattern to match
773 2nd operand: C expression that must be true
774 3rd operand: vector of insn patterns to place into a SEQUENCE
775 4th operand: optionally, some C code to execute before generating the
776 insns. This might, for example, create some RTX's and store them in
777 elements of `recog_data.operand' for use by the vector of
778 insn-patterns.
779 (`operands' is an alias here for `recog_data.operand'). */
780 DEF_RTL_EXPR(DEFINE_SPLIT, "define_split", "EsES", RTX_EXTRA)
781
782 /* Definition of an insn and associated split.
783 This is the concatenation, with a few modifications, of a define_insn
784 and a define_split which share the same pattern.
785 Operand:
786 0: names this instruction.
787 If the name is the null string, the instruction is in the
788 machine description just to be recognized, and will never be emitted by
789 the tree to rtl expander.
790 1: is the pattern.
791 2: is a string which is a C expression
792 giving an additional condition for recognizing this pattern.
793 A null string means no extra condition.
794 3: is the action to execute if this pattern is matched.
795 If this assembler code template starts with a * then it is a fragment of
796 C code to run to decide on a template to use. Otherwise, it is the
797 template to use.
798 4: C expression that must be true for split. This may start with "&&"
799 in which case the split condition is the logical and of the insn
800 condition and what follows the "&&" of this operand.
801 5: vector of insn patterns to place into a SEQUENCE
802 6: optionally, some C code to execute before generating the
803 insns. This might, for example, create some RTX's and store them in
804 elements of `recog_data.operand' for use by the vector of
805 insn-patterns.
806 (`operands' is an alias here for `recog_data.operand').
807 7: optionally, a vector of attributes for this insn. */
808 DEF_RTL_EXPR(DEFINE_INSN_AND_SPLIT, "define_insn_and_split", "sEsTsESV", RTX_EXTRA)
809
810 /* Definition of an RTL peephole operation.
811 Follows the same arguments as define_split. */
812 DEF_RTL_EXPR(DEFINE_PEEPHOLE2, "define_peephole2", "EsES", RTX_EXTRA)
813
814 /* Define how to generate multiple insns for a standard insn name.
815 1st operand: the insn name.
816 2nd operand: vector of insn-patterns.
817 Use match_operand to substitute an element of `recog_data.operand'.
818 3rd operand: C expression that must be true for this to be available.
819 This may not test any operands.
820 4th operand: Extra C code to execute before generating the insns.
821 This might, for example, create some RTX's and store them in
822 elements of `recog_data.operand' for use by the vector of
823 insn-patterns.
824 (`operands' is an alias here for `recog_data.operand'). */
825 DEF_RTL_EXPR(DEFINE_EXPAND, "define_expand", "sEss", RTX_EXTRA)
826
827 /* Define a requirement for delay slots.
828 1st operand: Condition involving insn attributes that, if true,
829 indicates that the insn requires the number of delay slots
830 shown.
831 2nd operand: Vector whose length is the three times the number of delay
832 slots required.
833 Each entry gives three conditions, each involving attributes.
834 The first must be true for an insn to occupy that delay slot
835 location. The second is true for all insns that can be
836 annulled if the branch is true and the third is true for all
837 insns that can be annulled if the branch is false.
838
839 Multiple DEFINE_DELAYs may be present. They indicate differing
840 requirements for delay slots. */
841 DEF_RTL_EXPR(DEFINE_DELAY, "define_delay", "eE", RTX_EXTRA)
842
843 /* Define attribute computation for `asm' instructions. */
844 DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES, "define_asm_attributes", "V", RTX_EXTRA)
845
846 /* Definition of a conditional execution meta operation. Automatically
847 generates new instances of DEFINE_INSN, selected by having attribute
848 "predicable" true. The new pattern will contain a COND_EXEC and the
849 predicate at top-level.
850
851 Operand:
852 0: The predicate pattern. The top-level form should match a
853 relational operator. Operands should have only one alternative.
854 1: A C expression giving an additional condition for recognizing
855 the generated pattern.
856 2: A template or C code to produce assembler output. */
857 DEF_RTL_EXPR(DEFINE_COND_EXEC, "define_cond_exec", "Ess", RTX_EXTRA)
858
859 /* Definition of an operand predicate. The difference between
860 DEFINE_PREDICATE and DEFINE_SPECIAL_PREDICATE is that genrecog will
861 not warn about a match_operand with no mode if it has a predicate
862 defined with DEFINE_SPECIAL_PREDICATE.
863
864 Operand:
865 0: The name of the predicate.
866 1: A boolean expression which computes whether or not the predicate
867 matches. This expression can use IOR, AND, NOT, MATCH_OPERAND,
868 MATCH_CODE, and MATCH_TEST. It must be specific enough that genrecog
869 can calculate the set of RTX codes that can possibly match.
870 2: A C function body which must return true for the predicate to match.
871 Optional. Use this when the test is too complicated to fit into a
872 match_test expression. */
873 DEF_RTL_EXPR(DEFINE_PREDICATE, "define_predicate", "ses", RTX_EXTRA)
874 DEF_RTL_EXPR(DEFINE_SPECIAL_PREDICATE, "define_special_predicate", "ses", RTX_EXTRA)
875
876 /* Definition of a register operand constraint. This simply maps the
877 constraint string to a register class.
878
879 Operand:
880 0: The name of the constraint (often, but not always, a single letter).
881 1: A C expression which evaluates to the appropriate register class for
882 this constraint. If this is not just a constant, it should look only
883 at -m switches and the like.
884 2: A docstring for this constraint, in Texinfo syntax; not currently
885 used, in future will be incorporated into the manual's list of
886 machine-specific operand constraints. */
887 DEF_RTL_EXPR(DEFINE_REGISTER_CONSTRAINT, "define_register_constraint", "sss", RTX_EXTRA)
888
889 /* Definition of a non-register operand constraint. These look at the
890 operand and decide whether it fits the constraint.
891
892 DEFINE_CONSTRAINT gets no special treatment if it fails to match.
893 It is appropriate for constant-only constraints, and most others.
894
895 DEFINE_MEMORY_CONSTRAINT tells reload that this constraint can be made
896 to match, if it doesn't already, by converting the operand to the form
897 (mem (reg X)) where X is a base register. It is suitable for constraints
898 that describe a subset of all memory references.
899
900 DEFINE_ADDRESS_CONSTRAINT tells reload that this constraint can be made
901 to match, if it doesn't already, by converting the operand to the form
902 (reg X) where X is a base register. It is suitable for constraints that
903 describe a subset of all address references.
904
905 When in doubt, use plain DEFINE_CONSTRAINT.
906
907 Operand:
908 0: The name of the constraint (often, but not always, a single letter).
909 1: A docstring for this constraint, in Texinfo syntax; not currently
910 used, in future will be incorporated into the manual's list of
911 machine-specific operand constraints.
912 2: A boolean expression which computes whether or not the constraint
913 matches. It should follow the same rules as a define_predicate
914 expression, including the bit about specifying the set of RTX codes
915 that could possibly match. MATCH_TEST subexpressions may make use of
916 these variables:
917 `op' - the RTL object defining the operand.
918 `mode' - the mode of `op'.
919 `ival' - INTVAL(op), if op is a CONST_INT.
920 `hval' - CONST_DOUBLE_HIGH(op), if op is an integer CONST_DOUBLE.
921 `lval' - CONST_DOUBLE_LOW(op), if op is an integer CONST_DOUBLE.
922 `rval' - CONST_DOUBLE_REAL_VALUE(op), if op is a floating-point
923 CONST_DOUBLE.
924 Do not use ival/hval/lval/rval if op is not the appropriate kind of
925 RTL object. */
926 DEF_RTL_EXPR(DEFINE_CONSTRAINT, "define_constraint", "sse", RTX_EXTRA)
927 DEF_RTL_EXPR(DEFINE_MEMORY_CONSTRAINT, "define_memory_constraint", "sse", RTX_EXTRA)
928 DEF_RTL_EXPR(DEFINE_ADDRESS_CONSTRAINT, "define_address_constraint", "sse", RTX_EXTRA)
929
930
931 /* Constructions for CPU pipeline description described by NDFAs. */
932
933 /* (define_cpu_unit string [string]) describes cpu functional
934 units (separated by comma).
935
936 1st operand: Names of cpu functional units.
937 2nd operand: Name of automaton (see comments for DEFINE_AUTOMATON).
938
939 All define_reservations, define_cpu_units, and
940 define_query_cpu_units should have unique names which may not be
941 "nothing". */
942 DEF_RTL_EXPR(DEFINE_CPU_UNIT, "define_cpu_unit", "sS", RTX_EXTRA)
943
944 /* (define_query_cpu_unit string [string]) describes cpu functional
945 units analogously to define_cpu_unit. The reservation of such
946 units can be queried for automaton state. */
947 DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT, "define_query_cpu_unit", "sS", RTX_EXTRA)
948
949 /* (exclusion_set string string) means that each CPU functional unit
950 in the first string can not be reserved simultaneously with any
951 unit whose name is in the second string and vise versa. CPU units
952 in the string are separated by commas. For example, it is useful
953 for description CPU with fully pipelined floating point functional
954 unit which can execute simultaneously only single floating point
955 insns or only double floating point insns. All CPU functional
956 units in a set should belong to the same automaton. */
957 DEF_RTL_EXPR(EXCLUSION_SET, "exclusion_set", "ss", RTX_EXTRA)
958
959 /* (presence_set string string) means that each CPU functional unit in
960 the first string can not be reserved unless at least one of pattern
961 of units whose names are in the second string is reserved. This is
962 an asymmetric relation. CPU units or unit patterns in the strings
963 are separated by commas. Pattern is one unit name or unit names
964 separated by white-spaces.
965
966 For example, it is useful for description that slot1 is reserved
967 after slot0 reservation for a VLIW processor. We could describe it
968 by the following construction
969
970 (presence_set "slot1" "slot0")
971
972 Or slot1 is reserved only after slot0 and unit b0 reservation. In
973 this case we could write
974
975 (presence_set "slot1" "slot0 b0")
976
977 All CPU functional units in a set should belong to the same
978 automaton. */
979 DEF_RTL_EXPR(PRESENCE_SET, "presence_set", "ss", RTX_EXTRA)
980
981 /* (final_presence_set string string) is analogous to `presence_set'.
982 The difference between them is when checking is done. When an
983 instruction is issued in given automaton state reflecting all
984 current and planned unit reservations, the automaton state is
985 changed. The first state is a source state, the second one is a
986 result state. Checking for `presence_set' is done on the source
987 state reservation, checking for `final_presence_set' is done on the
988 result reservation. This construction is useful to describe a
989 reservation which is actually two subsequent reservations. For
990 example, if we use
991
992 (presence_set "slot1" "slot0")
993
994 the following insn will be never issued (because slot1 requires
995 slot0 which is absent in the source state).
996
997 (define_reservation "insn_and_nop" "slot0 + slot1")
998
999 but it can be issued if we use analogous `final_presence_set'. */
1000 DEF_RTL_EXPR(FINAL_PRESENCE_SET, "final_presence_set", "ss", RTX_EXTRA)
1001
1002 /* (absence_set string string) means that each CPU functional unit in
1003 the first string can be reserved only if each pattern of units
1004 whose names are in the second string is not reserved. This is an
1005 asymmetric relation (actually exclusion set is analogous to this
1006 one but it is symmetric). CPU units or unit patterns in the string
1007 are separated by commas. Pattern is one unit name or unit names
1008 separated by white-spaces.
1009
1010 For example, it is useful for description that slot0 can not be
1011 reserved after slot1 or slot2 reservation for a VLIW processor. We
1012 could describe it by the following construction
1013
1014 (absence_set "slot2" "slot0, slot1")
1015
1016 Or slot2 can not be reserved if slot0 and unit b0 are reserved or
1017 slot1 and unit b1 are reserved . In this case we could write
1018
1019 (absence_set "slot2" "slot0 b0, slot1 b1")
1020
1021 All CPU functional units in a set should to belong the same
1022 automaton. */
1023 DEF_RTL_EXPR(ABSENCE_SET, "absence_set", "ss", RTX_EXTRA)
1024
1025 /* (final_absence_set string string) is analogous to `absence_set' but
1026 checking is done on the result (state) reservation. See comments
1027 for `final_presence_set'. */
1028 DEF_RTL_EXPR(FINAL_ABSENCE_SET, "final_absence_set", "ss", RTX_EXTRA)
1029
1030 /* (define_bypass number out_insn_names in_insn_names) names bypass
1031 with given latency (the first number) from insns given by the first
1032 string (see define_insn_reservation) into insns given by the second
1033 string. Insn names in the strings are separated by commas. The
1034 third operand is optional name of function which is additional
1035 guard for the bypass. The function will get the two insns as
1036 parameters. If the function returns zero the bypass will be
1037 ignored for this case. Additional guard is necessary to recognize
1038 complicated bypasses, e.g. when consumer is load address. */
1039 DEF_RTL_EXPR(DEFINE_BYPASS, "define_bypass", "issS", RTX_EXTRA)
1040
1041 /* (define_automaton string) describes names of automata generated and
1042 used for pipeline hazards recognition. The names are separated by
1043 comma. Actually it is possibly to generate the single automaton
1044 but unfortunately it can be very large. If we use more one
1045 automata, the summary size of the automata usually is less than the
1046 single one. The automaton name is used in define_cpu_unit and
1047 define_query_cpu_unit. All automata should have unique names. */
1048 DEF_RTL_EXPR(DEFINE_AUTOMATON, "define_automaton", "s", RTX_EXTRA)
1049
1050 /* (automata_option string) describes option for generation of
1051 automata. Currently there are the following options:
1052
1053 o "no-minimization" which makes no minimization of automata. This
1054 is only worth to do when we are debugging the description and
1055 need to look more accurately at reservations of states.
1056
1057 o "time" which means printing additional time statistics about
1058 generation of automata.
1059
1060 o "v" which means generation of file describing the result
1061 automata. The file has suffix `.dfa' and can be used for the
1062 description verification and debugging.
1063
1064 o "w" which means generation of warning instead of error for
1065 non-critical errors.
1066
1067 o "ndfa" which makes nondeterministic finite state automata.
1068
1069 o "progress" which means output of a progress bar showing how many
1070 states were generated so far for automaton being processed. */
1071 DEF_RTL_EXPR(AUTOMATA_OPTION, "automata_option", "s", RTX_EXTRA)
1072
1073 /* (define_reservation string string) names reservation (the first
1074 string) of cpu functional units (the 2nd string). Sometimes unit
1075 reservations for different insns contain common parts. In such
1076 case, you can describe common part and use its name (the 1st
1077 parameter) in regular expression in define_insn_reservation. All
1078 define_reservations, define_cpu_units, and define_query_cpu_units
1079 should have unique names which may not be "nothing". */
1080 DEF_RTL_EXPR(DEFINE_RESERVATION, "define_reservation", "ss", RTX_EXTRA)
1081
1082 /* (define_insn_reservation name default_latency condition regexpr)
1083 describes reservation of cpu functional units (the 3nd operand) for
1084 instruction which is selected by the condition (the 2nd parameter).
1085 The first parameter is used for output of debugging information.
1086 The reservations are described by a regular expression according
1087 the following syntax:
1088
1089 regexp = regexp "," oneof
1090 | oneof
1091
1092 oneof = oneof "|" allof
1093 | allof
1094
1095 allof = allof "+" repeat
1096 | repeat
1097
1098 repeat = element "*" number
1099 | element
1100
1101 element = cpu_function_unit_name
1102 | reservation_name
1103 | result_name
1104 | "nothing"
1105 | "(" regexp ")"
1106
1107 1. "," is used for describing start of the next cycle in
1108 reservation.
1109
1110 2. "|" is used for describing the reservation described by the
1111 first regular expression *or* the reservation described by the
1112 second regular expression *or* etc.
1113
1114 3. "+" is used for describing the reservation described by the
1115 first regular expression *and* the reservation described by the
1116 second regular expression *and* etc.
1117
1118 4. "*" is used for convenience and simply means sequence in
1119 which the regular expression are repeated NUMBER times with
1120 cycle advancing (see ",").
1121
1122 5. cpu functional unit name which means its reservation.
1123
1124 6. reservation name -- see define_reservation.
1125
1126 7. string "nothing" means no units reservation. */
1127
1128 DEF_RTL_EXPR(DEFINE_INSN_RESERVATION, "define_insn_reservation", "sies", RTX_EXTRA)
1129
1130 /* Expressions used for insn attributes. */
1131
1132 /* Definition of an insn attribute.
1133 1st operand: name of the attribute
1134 2nd operand: comma-separated list of possible attribute values
1135 3rd operand: expression for the default value of the attribute. */
1136 DEF_RTL_EXPR(DEFINE_ATTR, "define_attr", "sse", RTX_EXTRA)
1137
1138 /* Marker for the name of an attribute. */
1139 DEF_RTL_EXPR(ATTR, "attr", "s", RTX_EXTRA)
1140
1141 /* For use in the last (optional) operand of DEFINE_INSN or DEFINE_PEEPHOLE and
1142 in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that
1143 pattern.
1144
1145 (set_attr "name" "value") is equivalent to
1146 (set (attr "name") (const_string "value")) */
1147 DEF_RTL_EXPR(SET_ATTR, "set_attr", "ss", RTX_EXTRA)
1148
1149 /* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE, this can be used to
1150 specify that attribute values are to be assigned according to the
1151 alternative matched.
1152
1153 The following three expressions are equivalent:
1154
1155 (set (attr "att") (cond [(eq_attrq "alternative" "1") (const_string "a1")
1156 (eq_attrq "alternative" "2") (const_string "a2")]
1157 (const_string "a3")))
1158 (set_attr_alternative "att" [(const_string "a1") (const_string "a2")
1159 (const_string "a3")])
1160 (set_attr "att" "a1,a2,a3")
1161 */
1162 DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE, "set_attr_alternative", "sE", RTX_EXTRA)
1163
1164 /* A conditional expression true if the value of the specified attribute of
1165 the current insn equals the specified value. The first operand is the
1166 attribute name and the second is the comparison value. */
1167 DEF_RTL_EXPR(EQ_ATTR, "eq_attr", "ss", RTX_EXTRA)
1168
1169 /* A special case of the above representing a set of alternatives. The first
1170 operand is bitmap of the set, the second one is the default value. */
1171 DEF_RTL_EXPR(EQ_ATTR_ALT, "eq_attr_alt", "ii", RTX_EXTRA)
1172
1173 /* A conditional expression which is true if the specified flag is
1174 true for the insn being scheduled in reorg.
1175
1176 genattr.c defines the following flags which can be tested by
1177 (attr_flag "foo") expressions in eligible_for_delay.
1178
1179 forward, backward, very_likely, likely, very_unlikely, and unlikely. */
1180
1181 DEF_RTL_EXPR (ATTR_FLAG, "attr_flag", "s", RTX_EXTRA)
1182
1183 /* General conditional. The first operand is a vector composed of pairs of
1184 expressions. The first element of each pair is evaluated, in turn.
1185 The value of the conditional is the second expression of the first pair
1186 whose first expression evaluates nonzero. If none of the expressions is
1187 true, the second operand will be used as the value of the conditional. */
1188 DEF_RTL_EXPR(COND, "cond", "Ee", RTX_EXTRA)
1189
1190 #endif /* GENERATOR_FILE */
1191
1192 /*
1193 Local variables:
1194 mode:c
1195 End:
1196 */