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, 88, 92, 94, 95, 97, 98, 1999, 2000
5 Free Software Foundation, Inc.
7 This file is part of GCC.
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
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
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
25 /* Expression definitions and descriptions for all targets are in this file.
26 Some will not be used for some targets.
28 The fields in the cpp macro call "DEF_RTL_EXPR()"
29 are used to create declarations in the C source of the compiler.
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.
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.
42 3. The print format, and type of each rtx->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
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:
49 "o" an rtx code that can be used to represent an object (e.g, REG, MEM)
50 "<" an rtx code for a comparison (e.g, EQ, NE, LT)
51 "1" an rtx code for a unary arithmetic expression (e.g, NEG, NOT)
52 "c" an rtx code for a commutative binary operation (e.g,, PLUS, MULT)
53 "3" an rtx code for a non-bitfield three input operation (IF_THEN_ELSE)
54 "2" an rtx code for a non-commutative binary operation (e.g., MINUS, DIV)
55 "b" an rtx code for a bit-field operation (ZERO_EXTRACT, SIGN_EXTRACT)
56 "i" an rtx code for a machine insn (INSN, JUMP_INSN, CALL_INSN)
57 "m" an rtx code for something that matches in insns (e.g, MATCH_DUP)
58 "g" an rtx code for grouping insns together (e.g, GROUP_PARALLEL)
59 "a" an rtx code for autoincrement addressing modes (e.g. POST_DEC)
64 /* ---------------------------------------------------------------------
65 Expressions (and "meta" expressions) used for structuring the
66 rtl representation of a program.
67 --------------------------------------------------------------------- */
69 /* an expression code name unknown to the reader */
70 DEF_RTL_EXPR(UNKNOWN, "UnKnown", "*", 'x
')
72 /* (NIL) is used by rtl reader and printer to represent a null pointer. */
74 DEF_RTL_EXPR(NIL, "nil", "*", 'x
')
79 DEF_RTL_EXPR(INCLUDE, "include", "s", 'x
')
81 /* ---------------------------------------------------------------------
82 Expressions used in constructing lists.
83 --------------------------------------------------------------------- */
85 /* a linked list of expressions */
86 DEF_RTL_EXPR(EXPR_LIST, "expr_list", "ee", 'x
')
88 /* a linked list of instructions.
89 The insns are represented in print by their uids. */
90 DEF_RTL_EXPR(INSN_LIST, "insn_list", "ue", 'x
')
92 /* ----------------------------------------------------------------------
93 Expression types for machine descriptions.
94 These do not appear in actual rtl code in the compiler.
95 ---------------------------------------------------------------------- */
97 /* Appears only in machine descriptions.
98 Means use the function named by the second arg (the string)
99 as a predicate; if matched, store the structure that was matched
100 in the operand table at index specified by the first arg (the integer).
101 If the second arg is the null string, the structure is just stored.
103 A third string argument indicates to the register allocator restrictions
104 on where the operand can be allocated.
106 If the target needs no restriction on any instruction this field should
109 The string is prepended by:
110 '=' to indicate the operand is only written to.
111 '+' to indicate the operand is both read and written to.
113 Each character in the string represents an allocable class for an operand.
114 'g
' indicates the operand can be any valid class.
115 'i
' indicates the operand can be immediate (in the instruction) data.
116 'r
' indicates the operand can be in a register.
117 'm
' indicates the operand can be in memory.
118 'o
' a subset of the 'm
' class. Those memory addressing modes that
119 can be offset at compile time (have a constant added to them).
121 Other characters indicate target dependent operand classes and
122 are described in each target's machine description.
124 For instructions with more than one operand
, sets of classes can be
125 separated by a comma to indicate the appropriate multi
-operand constraints.
126 There must be a
1 to
1 correspondence between these sets of classes in
127 all operands for an instruction.
129 DEF_RTL_EXPR(MATCH_OPERAND
, "match_operand", "iss", 'm')
131 /* Appears only in machine descriptions.
132 Means match a SCRATCH or a register. When used to generate rtl
, a
133 SCRATCH is generated. As for MATCH_OPERAND
, the mode specifies
134 the desired mode and the first argument is the operand number.
135 The second argument is the constraint.
*/
136 DEF_RTL_EXPR(MATCH_SCRATCH
, "match_scratch", "is", 'm')
138 /* Appears only in machine descriptions.
139 Means match only something equal to what is stored in the operand table
140 at the index specified by the argument.
*/
141 DEF_RTL_EXPR(MATCH_DUP
, "match_dup", "i", 'm')
143 /* Appears only in machine descriptions.
144 Means apply a predicate
, AND match recursively the operands of the rtx.
145 Operand
0 is the operand
-number
, as in match_operand.
146 Operand
1 is a predicate to
apply (as a string
, a function name
).
147 Operand
2 is a vector of expressions
, each of which must match
148 one subexpression of the rtx this construct is matching.
*/
149 DEF_RTL_EXPR(MATCH_OPERATOR
, "match_operator", "isE", 'm')
151 /* Appears only in machine descriptions.
152 Means to match a PARALLEL of arbitrary length. The predicate is applied
153 to the PARALLEL and the initial expressions in the PARALLEL are matched.
154 Operand
0 is the operand
-number
, as in match_operand.
155 Operand
1 is a predicate to apply to the PARALLEL.
156 Operand
2 is a vector of expressions
, each of which must match the
157 corresponding element in the PARALLEL.
*/
158 DEF_RTL_EXPR(MATCH_PARALLEL
, "match_parallel", "isE", 'm')
160 /* Appears only in machine descriptions.
161 Means match only something equal to what is stored in the operand table
162 at the index specified by the argument. For MATCH_OPERATOR.
*/
163 DEF_RTL_EXPR(MATCH_OP_DUP
, "match_op_dup", "iE", 'm')
165 /* Appears only in machine descriptions.
166 Means match only something equal to what is stored in the operand table
167 at the index specified by the argument. For MATCH_PARALLEL.
*/
168 DEF_RTL_EXPR(MATCH_PAR_DUP
, "match_par_dup", "iE", 'm')
170 /* Appears only in machine descriptions.
171 Operand
0 is the operand number
, as in match_operand.
172 Operand
1 is the predicate to apply to the insn.
*/
173 DEF_RTL_EXPR(MATCH_INSN
, "match_insn", "is", 'm')
175 /* Appears only in machine descriptions.
176 Defines the pattern for one kind of instruction.
178 0: names this instruction.
179 If the name is the null string
, the instruction is in the
180 machine description just to be recognized
, and will never be emitted by
181 the tree to rtl expander.
183 2: is a string which is a C expression
184 giving an additional condition for recognizing this pattern.
185 A null string means no extra condition.
186 3: is the action to execute if this pattern is matched.
187 If this assembler code template starts with a
* then it is a fragment of
188 C code to run to decide on a template to use. Otherwise
, it is the
190 4: optionally
, a vector of attributes for this insn.
192 DEF_RTL_EXPR(DEFINE_INSN
, "define_insn", "sEsTV", 'x')
194 /* Definition of a peephole optimization.
195 1st operand
: vector of insn patterns to match
196 2nd operand
: C expression that must be true
197 3rd operand
: template or C code to produce assembler output.
198 4: optionally
, a vector of attributes for this insn.
200 DEF_RTL_EXPR(DEFINE_PEEPHOLE
, "define_peephole", "EsTV", 'x')
202 /* Definition of a split operation.
203 1st operand
: insn pattern to match
204 2nd operand
: C expression that must be true
205 3rd operand
: vector of insn patterns to place into a SEQUENCE
206 4th operand
: optionally
, some C code to execute before generating the
207 insns. This might
, for example
, create some RTX
's and store them in
208 elements of `recog_data.operand' for use by the vector of
210 (`operands
' is an alias here for `recog_data.operand').
*/
211 DEF_RTL_EXPR(DEFINE_SPLIT
, "define_split", "EsES", 'x')
213 /* Definition of an insn and associated split.
214 This is the concatenation
, with a few modifications
, of a define_insn
215 and a define_split which share the same pattern.
217 0: names this instruction.
218 If the name is the null string
, the instruction is in the
219 machine description just to be recognized
, and will never be emitted by
220 the tree to rtl expander.
222 2: is a string which is a C expression
223 giving an additional condition for recognizing this pattern.
224 A null string means no extra condition.
225 3: is the action to execute if this pattern is matched.
226 If this assembler code template starts with a
* then it is a fragment of
227 C code to run to decide on a template to use. Otherwise
, it is the
229 4: C expression that must be true for split. This may start with
"&&"
230 in which case the split condition is the logical and of the insn
231 condition and what follows the
"&&" of this operand.
232 5: vector of insn patterns to place into a SEQUENCE
233 6: optionally
, some C code to execute before generating the
234 insns. This might
, for example
, create some RTX
's and store them in
235 elements of `recog_data.operand' for use by the vector of
237 (`operands
' is an alias here for `recog_data.operand').
238 7: optionally
, a vector of attributes for this insn.
*/
239 DEF_RTL_EXPR(DEFINE_INSN_AND_SPLIT
, "define_insn_and_split", "sEsTsESV", 'x')
241 /* Definition of an RTL peephole operation.
242 Follows the same arguments as define_split.
*/
243 DEF_RTL_EXPR(DEFINE_PEEPHOLE2
, "define_peephole2", "EsES", 'x')
245 /* Definition of a combiner pattern.
246 Operands not defined yet.
*/
247 DEF_RTL_EXPR(DEFINE_COMBINE
, "define_combine", "Ess", 'x')
249 /* Define how to generate multiple insns for a standard insn name.
250 1st operand
: the insn name.
251 2nd operand
: vector of insn
-patterns.
252 Use match_operand to substitute an element of `recog_data.operand
'.
253 3rd operand: C expression that must be true for this to be available.
254 This may not test any operands.
255 4th operand: Extra C code to execute before generating the insns.
256 This might, for example, create some RTX's and store them in
257 elements of `recog_data.operand
' for use by the vector of
259 (`operands' is an alias here for `recog_data.operand
'). */
260 DEF_RTL_EXPR(DEFINE_EXPAND, "define_expand", "sEss", 'x
')
262 /* Define a requirement for delay slots.
263 1st operand: Condition involving insn attributes that, if true,
264 indicates that the insn requires the number of delay slots
266 2nd operand: Vector whose length is the three times the number of delay
268 Each entry gives three conditions, each involving attributes.
269 The first must be true for an insn to occupy that delay slot
270 location. The second is true for all insns that can be
271 annulled if the branch is true and the third is true for all
272 insns that can be annulled if the branch is false.
274 Multiple DEFINE_DELAYs may be present. They indicate differing
275 requirements for delay slots. */
276 DEF_RTL_EXPR(DEFINE_DELAY, "define_delay", "eE", 'x
')
278 /* Define a set of insns that requires a function unit. This means that
279 these insns produce their result after a delay and that there may be
280 restrictions on the number of insns of this type that can be scheduled
283 More than one DEFINE_FUNCTION_UNIT can be specified for a function unit.
284 Each gives a set of operations and associated delays. The first three
285 operands must be the same for each operation for the same function unit.
287 All delays are specified in cycles.
289 1st operand: Name of function unit (mostly for documentation)
290 2nd operand: Number of identical function units in CPU
291 3rd operand: Total number of simultaneous insns that can execute on this
292 function unit; 0 if unlimited.
293 4th operand: Condition involving insn attribute, that, if true, specifies
294 those insns that this expression applies to.
295 5th operand: Constant delay after which insn result will be
297 6th operand: Delay until next insn can be scheduled on the function unit
298 executing this operation. The meaning depends on whether or
299 not the next operand is supplied.
300 7th operand: If this operand is not specified, the 6th operand gives the
301 number of cycles after the instruction matching the 4th
302 operand begins using the function unit until a subsequent
303 insn can begin. A value of zero should be used for a
304 unit with no issue constraints. If only one operation can
305 be executed a time and the unit is busy for the entire time,
306 the 3rd operand should be specified as 1, the 6th operand
307 should be specified as 0, and the 7th operand should not
310 If this operand is specified, it is a list of attribute
311 expressions. If an insn for which any of these expressions
312 is true is currently executing on the function unit, the
313 issue delay will be given by the 6th operand. Otherwise,
314 the insn can be immediately scheduled (subject to the limit
315 on the number of simultaneous operations executing on the
317 DEF_RTL_EXPR(DEFINE_FUNCTION_UNIT, "define_function_unit", "siieiiV", 'x
')
319 /* Define attribute computation for `asm' instructions.
*/
320 DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES
, "define_asm_attributes", "V", 'x' )
322 /* Definition of a conditional execution meta operation. Automatically
323 generates new instances of DEFINE_INSN
, selected by having attribute
324 "predicable" true. The new pattern will contain a COND_EXEC and the
325 predicate at top
-level.
328 0: The predicate pattern. The top
-level form should match a
329 relational operator. Operands should have only one alternative.
330 1: A C expression giving an additional condition for recognizing
331 the generated pattern.
332 2: A template or C code to produce assembler output.
*/
333 DEF_RTL_EXPR(DEFINE_COND_EXEC
, "define_cond_exec", "Ess", 'x')
335 /* SEQUENCE appears in the result of a `gen_...
' function
336 for a DEFINE_EXPAND that wants to make several insns.
337 Its elements are the bodies of the insns that should be made.
338 `emit_insn' takes the SEQUENCE apart and makes separate insns.
*/
339 DEF_RTL_EXPR(SEQUENCE
, "sequence", "E", 'x')
341 /* Refers to the address of its argument. This is only used in alias.c.
*/
342 DEF_RTL_EXPR(ADDRESS
, "address", "e", 'm')
344 /* ----------------------------------------------------------------------
345 Constructions for CPU pipeline description described by NDFAs.
346 These do not appear in actual rtl code in the compiler.
347 ---------------------------------------------------------------------- */
349 /* (define_cpu_unit string
[string
]) describes cpu functional
350 units (separated by comma
).
352 1st operand
: Names of cpu functional units.
353 2nd operand
: Name of
automaton (see comments for DEFINE_AUTOMATON
).
355 All define_reservations
, define_cpu_units
, and
356 define_query_cpu_units should have unique names which may not be
358 DEF_RTL_EXPR(DEFINE_CPU_UNIT
, "define_cpu_unit", "sS", 'x')
360 /* (define_query_cpu_unit string
[string
]) describes cpu functional
361 units analogously to define_cpu_unit. If we use automaton without
362 minimization
, the reservation of such units can be queried for
364 DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT
, "define_query_cpu_unit", "sS", 'x')
366 /* (exclusion_set string string
) means that each CPU functional unit
367 in the first string can not be reserved simultaneously with any
368 unit whose name is in the second string and vise versa. CPU units
369 in the string are separated by commas. For example
, it is useful
370 for description CPU with fully pipelined floating point functional
371 unit which can execute simultaneously only single floating point
372 insns or only double floating point insns. All CPU functional
373 units in a set should belong the same automaton.
*/
374 DEF_RTL_EXPR(EXCLUSION_SET
, "exclusion_set", "ss", 'x')
376 /* (presence_set string string
) means that each CPU functional unit in
377 the first string can not be reserved unless at least one of units
378 whose names are in the second string is reserved. This is an
379 asymmetric relation. CPU units in the string are separated by
380 commas. For example
, it is useful for description that slot1 is
381 reserved after slot0 reservation for VLIW processor. All CPU
382 functional units in a set should belong the same automaton.
*/
383 DEF_RTL_EXPR(PRESENCE_SET
, "presence_set", "ss", 'x')
385 /* (absence_set string string
) means that each CPU functional unit in
386 the first string can not be reserved only if each unit whose name
387 is in the second string is not reserved. This is an asymmetric
388 relation (actually exclusion set is analogous to this one but it is
389 symmetric
). CPU units in the string are separated by commas. For
390 example
, it is useful for description that slot0 can not be
391 reserved after slot1 or slot2 reservation for VLIW processor. All
392 CPU functional units in a set should belong the same automaton.
*/
393 DEF_RTL_EXPR(ABSENCE_SET
, "absence_set", "ss", 'x')
395 /* (define_bypass number out_insn_names in_insn_names
) names bypass
396 with given
latency (the first number
) from insns given by the first
397 string (see define_insn_reservation
) into insns given by the second
398 string. Insn names in the strings are separated by commas. The
399 third operand is optional name of function which is additional
400 guard for the bypass. The function will get the two insns as
401 parameters. If the function returns zero the bypass will be
402 ignored for this case. Additional guard is necessary to recognize
403 complicated bypasses
, e.g. when consumer is load address.
*/
404 DEF_RTL_EXPR(DEFINE_BYPASS
, "define_bypass", "issS", 'x')
406 /* (define_automaton string
) describes names of automata generated and
407 used for pipeline hazards recognition. The names are separated by
408 comma. Actually it is possibly to generate the single automaton
409 but unfortunately it can be very large. If we use more one
410 automata
, the summary size of the automata usually is less than the
411 single one. The automaton name is used in define_cpu_unit and
412 define_query_cpu_unit. All automata should have unique names.
*/
413 DEF_RTL_EXPR(DEFINE_AUTOMATON
, "define_automaton", "s", 'x')
415 /* (automata_option string
) describes option for generation of
416 automata. Currently there are the following options
:
418 o
"no-minimization" which makes no minimization of automata. This
419 is only worth to do when we are going to query CPU functional
420 unit reservations in an automaton state.
422 o
"w" which means generation of file describing the result
423 automaton. The file can be used for the description verification.
425 o
"ndfa" which makes nondeterministic finite state automata.
*/
426 DEF_RTL_EXPR(AUTOMATA_OPTION
, "automata_option", "s", 'x')
428 /* (define_reservation string string
) names
reservation (the first
429 string
) of cpu functional
units (the
2nd string
). Sometimes unit
430 reservations for different insns contain common parts. In such
431 case
, you can describe common part and use its
name (the
1st
432 parameter
) in regular expression in define_insn_reservation. All
433 define_reservations
, define_cpu_units
, and define_query_cpu_units
434 should have unique names which may not be
"nothing".
*/
435 DEF_RTL_EXPR(DEFINE_RESERVATION
, "define_reservation", "ss", 'x')
437 /* (define_insn_reservation name default_latency condition regexpr
)
438 describes reservation of cpu functional
units (the
3nd operand
) for
439 instruction which is selected by the
condition (the
2nd parameter
).
440 The first parameter is used for output of debugging information.
441 The reservations are described by a regular expression according
442 the following syntax
:
444 regexp
= regexp
"," oneof
447 oneof
= oneof
"|" allof
450 allof
= allof
"+" repeat
453 repeat
= element
"*" number
456 element
= cpu_function_unit_name
462 1.
"," is used for describing start of the next cycle in
465 2.
"|" is used for describing the reservation described by the
466 first regular expression
*or
* the reservation described by the
467 second regular expression
*or
* etc.
469 3.
"+" is used for describing the reservation described by the
470 first regular expression
*and
* the reservation described by the
471 second regular expression
*and
* etc.
473 4.
"*" is used for convinience and simply means sequence in
474 which the regular expression are repeated NUMBER times with
475 cycle
advancing (see
",").
477 5. cpu functional unit name which means its reservation.
479 6. reservation name
-- see define_reservation.
481 7. string
"nothing" means no units reservation.
*/
483 DEF_RTL_EXPR(DEFINE_INSN_RESERVATION
, "define_insn_reservation", "sies", 'x')
485 /* ----------------------------------------------------------------------
486 Expressions used for insn attributes. These also do not appear in
487 actual rtl code in the compiler.
488 ---------------------------------------------------------------------- */
490 /* Definition of an insn attribute.
491 1st operand
: name of the attribute
492 2nd operand
: comma
-separated list of possible attribute values
493 3rd operand
: expression for the default value of the attribute.
*/
494 DEF_RTL_EXPR(DEFINE_ATTR
, "define_attr", "sse", 'x')
496 /* Marker for the name of an attribute.
*/
497 DEF_RTL_EXPR(ATTR
, "attr", "s", 'x')
499 /* For use in the
last (optional
) operand of DEFINE_INSN or DEFINE_PEEPHOLE and
500 in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that
503 (set_attr
"name" "value") is equivalent to
504 (set (attr
"name") (const_string
"value")) */
505 DEF_RTL_EXPR(SET_ATTR
, "set_attr", "ss", 'x')
507 /* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE
, this can be used to
508 specify that attribute values are to be assigned according to the
511 The following three expressions are equivalent
:
513 (set (attr
"att") (cond
[(eq_attrq
"alternative" "1") (const_string
"a1")
514 (eq_attrq
"alternative" "2") (const_string
"a2")]
515 (const_string
"a3")))
516 (set_attr_alternative
"att" [(const_string
"a1") (const_string
"a2")
517 (const_string
"a3")])
518 (set_attr
"att" "a1,a2,a3")
520 DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE
, "set_attr_alternative", "sE", 'x')
522 /* A conditional expression true if the value of the specified attribute of
523 the current insn equals the specified value. The first operand is the
524 attribute name and the second is the comparison value.
*/
525 DEF_RTL_EXPR(EQ_ATTR
, "eq_attr", "ss", 'x')
527 /* A conditional expression which is true if the specified flag is
528 true for the insn being scheduled in reorg.
530 genattr.c defines the following flags which can be tested by
531 (attr_flag
"foo") expressions in eligible_for_delay.
533 forward
, backward
, very_likely
, likely
, very_unlikely
, and unlikely.
*/
535 DEF_RTL_EXPR (ATTR_FLAG
, "attr_flag", "s", 'x')
537 /* ----------------------------------------------------------------------
538 Expression types used for things in the instruction chain.
540 All formats must start with
"iuu" to handle the chain.
541 Each insn expression holds an rtl instruction and its semantics
542 during back
-end processing.
543 See macros
's in "rtl.h" for the meaning of each rtx->fld[].
545 ---------------------------------------------------------------------- */
547 /* An instruction that cannot jump. */
548 DEF_RTL_EXPR(INSN, "insn", "iuueiee", 'i
')
550 /* An instruction that can possibly jump.
551 Fields ( rtx->fld[] ) have exact same meaning as INSN's.
*/
552 DEF_RTL_EXPR(JUMP_INSN
, "jump_insn", "iuueiee0", 'i')
554 /* An instruction that can possibly call a subroutine
555 but which will not change which instruction comes next
556 in the current function.
557 Field ( rtx
->fld
[7] ) is CALL_INSN_FUNCTION_USAGE.
558 All other
fields ( rtx
->fld
[] ) have exact same meaning as INSN
's. */
559 DEF_RTL_EXPR(CALL_INSN, "call_insn", "iuueieee", 'i
')
561 /* A marker that indicates that control will not flow through. */
562 DEF_RTL_EXPR(BARRIER, "barrier", "iuu", 'x
')
564 /* Holds a label that is followed by instructions.
566 3: is used in jump.c for the use-count of the label.
567 4: is used in flow.c to point to the chain of label_ref's to this label.
568 5: is a number that is unique in the entire compilation.
569 6: is the user
-given name of the label
, if any.
570 7: is the alternate label name.
*/
571 DEF_RTL_EXPR(CODE_LABEL
, "code_label", "iuu00iss", 'x')
573 /* Say where in the code a source line starts
, for symbol table
's sake.
575 3: filename, if line number > 0, note-specific data otherwise.
576 4: line number if > 0, enum note_insn otherwise.
577 5: unique number if line number == note_insn_deleted_label. */
578 DEF_RTL_EXPR(NOTE, "note", "iuu0ni", 'x
')
580 /* ----------------------------------------------------------------------
581 Top level constituents of INSN, JUMP_INSN and CALL_INSN.
582 ---------------------------------------------------------------------- */
584 /* Conditionally execute code.
585 Operand 0 is the condition that if true, the code is executed.
586 Operand 1 is the code to be executed (typically a SET).
588 Semantics are that there are no side effects if the condition
589 is false. This pattern is created automatically by the if_convert
590 pass run after reload or by target-specific splitters. */
591 DEF_RTL_EXPR(COND_EXEC, "cond_exec", "ee", 'x
')
593 /* Several operations to be done in parallel (perhaps under COND_EXEC). */
594 DEF_RTL_EXPR(PARALLEL, "parallel", "E", 'x
')
596 /* A string that is passed through to the assembler as input.
597 One can obviously pass comments through by using the
598 assembler comment syntax.
599 These occur in an insn all by themselves as the PATTERN.
600 They also appear inside an ASM_OPERANDS
601 as a convenient way to hold a string. */
602 DEF_RTL_EXPR(ASM_INPUT, "asm_input", "s", 'x
')
604 /* An assembler instruction with operands.
605 1st operand is the instruction template.
606 2nd operand is the constraint for the output.
607 3rd operand is the number of the output this expression refers to.
608 When an insn stores more than one value, a separate ASM_OPERANDS
609 is made for each output; this integer distinguishes them.
610 4th is a vector of values of input operands.
611 5th is a vector of modes and constraints for the input operands.
612 Each element is an ASM_INPUT containing a constraint string
613 and whose mode indicates the mode of the input operand.
614 6th is the name of the containing source file.
615 7th is the source line number. */
616 DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEsi", 'x
')
618 /* A machine-specific operation.
619 1st operand is a vector of operands being used by the operation so that
620 any needed reloads can be done.
621 2nd operand is a unique value saying which of a number of machine-specific
622 operations is to be performed.
623 (Note that the vector must be the first operand because of the way that
624 genrecog.c record positions within an insn.)
625 This can occur all by itself in a PATTERN, as a component of a PARALLEL,
626 or inside an expression. */
627 DEF_RTL_EXPR(UNSPEC, "unspec", "Ei", 'x
')
629 /* Similar, but a volatile operation and one which may trap. */
630 DEF_RTL_EXPR(UNSPEC_VOLATILE, "unspec_volatile", "Ei", 'x
')
632 /* Vector of addresses, stored as full words. */
633 /* Each element is a LABEL_REF to a CODE_LABEL whose address we want. */
634 DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", 'x
')
636 /* Vector of address differences X0 - BASE, X1 - BASE, ...
637 First operand is BASE; the vector contains the X's.
638 The machine mode of this rtx says how much space to leave
639 for each difference and is adjusted by branch shortening if
640 CASE_VECTOR_SHORTEN_MODE is defined.
641 The third and fourth operands store the target labels with the
642 minimum and maximum addresses respectively.
643 The fifth operand stores flags for use by branch shortening.
644 Set at the start of shorten_branches
:
645 min_align
: the minimum alignment for any of the target labels.
646 base_after_vec
: true iff BASE is after the ADDR_DIFF_VEC.
647 min_after_vec
: true iff minimum addr target label is after the ADDR_DIFF_VEC.
648 max_after_vec
: true iff maximum addr target label is after the ADDR_DIFF_VEC.
649 min_after_base
: true iff minimum address target label is after BASE.
650 max_after_base
: true iff maximum address target label is after BASE.
651 Set by the actual branch shortening process
:
652 offset_unsigned
: true iff offsets have to be treated as unsigned.
653 scale
: scaling that is necessary to make offsets fit into the mode.
655 The third
, fourth and fifth operands are only valid when
656 CASE_VECTOR_SHORTEN_MODE is defined
, and only in an optimizing
659 DEF_RTL_EXPR(ADDR_DIFF_VEC
, "addr_diff_vec", "eEee0", 'x')
661 /* Memory prefetch
, with attributes supported on some targets.
662 Operand
1 is the address of the memory to fetch.
663 Operand
2 is
1 for a write access
, 0 otherwise.
664 Operand
3 is the level of temporal locality
; 0 means there is no
665 temporal locality and
1, 2, and
3 are for increasing levels of temporal
668 The attributes specified by operands
2 and
3 are ignored for targets
669 whose prefetch instructions do not support them.
*/
670 DEF_RTL_EXPR(PREFETCH
, "prefetch", "eee", 'x')
672 /* ----------------------------------------------------------------------
673 At the top level of an
instruction (perhaps under PARALLEL
).
674 ---------------------------------------------------------------------- */
677 Operand
1 is the
location (REG
, MEM
, PC
, CC0 or whatever
) assigned to.
678 Operand
2 is the value stored there.
679 ALL assignment must use
SET.
680 Instructions that do multiple assignments must use multiple
SET,
682 DEF_RTL_EXPR(SET, "set", "ee", 'x')
684 /* Indicate something is used in a way that we don
't want to explain.
685 For example, subroutine calls will use the register
686 in which the static chain is passed. */
687 DEF_RTL_EXPR(USE, "use", "e", 'x
')
689 /* Indicate something is clobbered in a way that we don't want to explain.
690 For example
, subroutine calls will clobber some physical registers
691 (the ones that are by convention not saved
).
*/
692 DEF_RTL_EXPR(CLOBBER
, "clobber", "e", 'x')
694 /* Call a subroutine.
695 Operand
1 is the address to call.
696 Operand
2 is the number of arguments.
*/
698 DEF_RTL_EXPR(CALL
, "call", "ee", 'x')
700 /* Return from a subroutine.
*/
702 DEF_RTL_EXPR(RETURN, "return", "", 'x')
705 Operand
1 is the condition.
706 Operand
2 is the trap code.
707 For an unconditional trap
, make the
condition (const_int
1).
*/
708 DEF_RTL_EXPR(TRAP_IF
, "trap_if", "ee", 'x')
710 /* Placeholder for _Unwind_Resume before we know if a function call
711 or a branch is needed. Operand
1 is the exception region from
712 which control is flowing.
*/
713 DEF_RTL_EXPR(RESX
, "resx", "i", 'x')
715 /* ----------------------------------------------------------------------
716 Primitive values for use in expressions.
717 ---------------------------------------------------------------------- */
719 /* numeric integer constant
*/
720 DEF_RTL_EXPR(CONST_INT
, "const_int", "w", 'o')
722 /* numeric floating point constant.
723 Operand
0 ('0') is a chain of all CONST_DOUBLEs in use in the
725 Remaining operands hold the actual value. They are all
'w' and
726 there may be from
1 to
4; see rtl.c.
*/
727 DEF_RTL_EXPR(CONST_DOUBLE
, "const_double", CONST_DOUBLE_FORMAT
, 'o')
729 /* Describes a vector constant.
*/
730 DEF_RTL_EXPR(CONST_VECTOR
, "const_vector", "E", 'x')
732 /* String constant. Used only for attributes right now.
*/
733 DEF_RTL_EXPR(CONST_STRING
, "const_string", "s", 'o')
735 /* This is used to encapsulate an expression whose value is constant
736 (such as the sum of a SYMBOL_REF and a CONST_INT
) so that it will be
737 recognized as a constant operand rather than by arithmetic instructions.
*/
739 DEF_RTL_EXPR(CONST, "const", "e", 'o')
741 /* program counter. Ordinary jumps are represented
742 by a
SET whose first operand
is (PC
).
*/
743 DEF_RTL_EXPR(PC
, "pc", "", 'o')
745 /* Used in the cselib routines to describe a value.
*/
746 DEF_RTL_EXPR(VALUE
, "value", "0", 'o')
748 /* A register. The
"operand" is the register number
, accessed with
749 the REGNO macro. If this number is less than FIRST_PSEUDO_REGISTER
750 than a hardware register is being referred to. The second operand
751 holds the original register number
- this will be different for a
752 pseudo register that got turned into a hard register.
753 This rtx needs to have as
many (or more
) fields as a MEM
, since we
754 can change REG rtx
's into MEMs during reload. */
755 DEF_RTL_EXPR(REG, "reg", "i0", 'o
')
757 /* A scratch register. This represents a register used only within a
758 single insn. It will be turned into a REG during register allocation
759 or reload unless the constraint indicates that the register won't be
760 needed
, in which case it can remain a SCRATCH. This code is
761 marked as having one operand so it can be turned into a REG.
*/
762 DEF_RTL_EXPR(SCRATCH
, "scratch", "0", 'o')
764 /* One word of a multi
-word value.
765 The first operand is the complete value
; the second says which word.
766 The WORDS_BIG_ENDIAN flag controls whether word number
0
767 (as numbered in a SUBREG
) is the most or least significant word.
769 This is also used to refer to a value in a different machine mode.
770 For example
, it can be used to refer to a SImode value as if it were
771 Qimode
, or vice versa. Then the word number is always
0.
*/
772 DEF_RTL_EXPR(SUBREG
, "subreg", "ei", 'x')
774 /* This one
-argument rtx is used for move instructions
775 that are guaranteed to alter only the low part of a destination.
776 Thus
, (SET (SUBREG
:HI (REG...
)) (MEM
:HI ...
))
777 has an unspecified effect on the high part of REG
,
778 but (SET (STRICT_LOW_PART (SUBREG
:HI (REG...
))) (MEM
:HI ...
))
779 is guaranteed to alter only the bits of REG that are in HImode.
781 The actual instruction used is probably the same in both cases
,
782 but the register constraints may be tighter when STRICT_LOW_PART
785 DEF_RTL_EXPR(STRICT_LOW_PART
, "strict_low_part", "e", 'x')
787 /* (CONCAT a b
) represents the virtual concatenation of a and b
788 to make a value that has as many bits as a and b put together.
789 This is used for complex values. Normally it appears only
790 in DECL_RTLs and during RTL generation
, but not in the insn chain.
*/
791 DEF_RTL_EXPR(CONCAT
, "concat", "ee", 'o')
793 /* A memory location
; operand is the address. The second operand is the
794 alias set to which this MEM belongs. We use `
0' instead of `w' for this
795 field so that the field need not be specified in machine descriptions.
*/
796 DEF_RTL_EXPR(MEM
, "mem", "e0", 'o')
798 /* Reference to an assembler label in the code for this function.
799 The operand is a CODE_LABEL found in the insn chain.
800 The unprinted fields
1 and
2 are used in flow.c for the
801 LABEL_NEXTREF and CONTAINING_INSN.
*/
802 DEF_RTL_EXPR(LABEL_REF
, "label_ref", "u00", 'o')
804 /* Reference to a named label
: the string that is the first operand
,
805 with `_
' added implicitly in front.
806 Exception: if the first character explicitly given is `*',
807 to give it to the assembler
, remove the `
*' and do not add `_'.
*/
808 DEF_RTL_EXPR(SYMBOL_REF
, "symbol_ref", "s", 'o')
810 /* The condition code register is represented
, in our imagination
,
811 as a register holding a value that can be compared to zero.
812 In fact
, the machine has already compared them and recorded the
813 results
; but instructions that look at the condition code
814 pretend to be looking at the entire value and comparing it.
*/
815 DEF_RTL_EXPR(CC0
, "cc0", "", 'o')
817 /* Reference to the address of a register. Removed by purge_addressof after
818 CSE has elided as many as possible.
819 1st operand
: the register we may need the address of.
820 2nd operand
: the original pseudo regno we were generated for.
821 3rd operand
: the decl for the object in the register
, for
824 DEF_RTL_EXPR(ADDRESSOF
, "addressof", "eit", 'o')
826 /* =====================================================================
827 A QUEUED expression really points to a member of the queue of instructions
828 to be output later for postincrement
/postdecrement.
829 QUEUED expressions never become part of instructions.
830 When a QUEUED expression would be put into an instruction
,
831 instead either the incremented variable or a copy of its previous
835 0. the variable to be
incremented (a REG rtx
).
836 1. the incrementing instruction
, or
0 if it hasn
't been output yet.
837 2. A REG rtx for a copy of the old value of the variable, or 0 if none yet.
838 3. the body to use for the incrementing instruction
839 4. the next QUEUED expression in the queue.
840 ====================================================================== */
842 DEF_RTL_EXPR(QUEUED, "queued", "eeeee", 'x
')
844 /* ----------------------------------------------------------------------
845 Expressions for operators in an rtl pattern
846 ---------------------------------------------------------------------- */
848 /* if_then_else. This is used in representing ordinary
849 conditional jump instructions.
854 DEF_RTL_EXPR(IF_THEN_ELSE, "if_then_else", "eee", '3')
856 /* General conditional. The first operand is a vector composed of pairs of
857 expressions. The first element of each pair is evaluated, in turn.
858 The value of the conditional is the second expression of the first pair
859 whose first expression evaluates non-zero. If none of the expressions is
860 true, the second operand will be used as the value of the conditional.
862 This should be replaced with use of IF_THEN_ELSE. */
863 DEF_RTL_EXPR(COND, "cond", "Ee", 'x
')
865 /* Comparison, produces a condition code result. */
866 DEF_RTL_EXPR(COMPARE, "compare", "ee", '2')
869 DEF_RTL_EXPR(PLUS, "plus", "ee", 'c
')
871 /* Operand 0 minus operand 1. */
872 DEF_RTL_EXPR(MINUS, "minus", "ee", '2')
874 /* Minus operand 0. */
875 DEF_RTL_EXPR(NEG, "neg", "e", '1')
877 DEF_RTL_EXPR(MULT, "mult", "ee", 'c
')
879 /* Operand 0 divided by operand 1. */
880 DEF_RTL_EXPR(DIV, "div", "ee", '2')
881 /* Remainder of operand 0 divided by operand 1. */
882 DEF_RTL_EXPR(MOD, "mod", "ee", '2')
884 /* Unsigned divide and remainder. */
885 DEF_RTL_EXPR(UDIV, "udiv", "ee", '2')
886 DEF_RTL_EXPR(UMOD, "umod", "ee", '2')
888 /* Bitwise operations. */
889 DEF_RTL_EXPR(AND, "and", "ee", 'c
')
891 DEF_RTL_EXPR(IOR, "ior", "ee", 'c
')
893 DEF_RTL_EXPR(XOR, "xor", "ee", 'c
')
895 DEF_RTL_EXPR(NOT, "not", "e", '1')
898 0: value to be shifted.
899 1: number of bits. */
900 DEF_RTL_EXPR(ASHIFT, "ashift", "ee", '2') /* shift left */
901 DEF_RTL_EXPR(ROTATE, "rotate", "ee", '2') /* rotate left */
902 DEF_RTL_EXPR(ASHIFTRT, "ashiftrt", "ee", '2') /* arithmetic shift right */
903 DEF_RTL_EXPR(LSHIFTRT, "lshiftrt", "ee", '2') /* logical shift right */
904 DEF_RTL_EXPR(ROTATERT, "rotatert", "ee", '2') /* rotate right */
906 /* Minimum and maximum values of two operands. We need both signed and
907 unsigned forms. (We cannot use MIN for SMIN because it conflicts
908 with a macro of the same name.) */
910 DEF_RTL_EXPR(SMIN, "smin", "ee", 'c
')
911 DEF_RTL_EXPR(SMAX, "smax", "ee", 'c
')
912 DEF_RTL_EXPR(UMIN, "umin", "ee", 'c
')
913 DEF_RTL_EXPR(UMAX, "umax", "ee", 'c
')
915 /* These unary operations are used to represent incrementation
916 and decrementation as they occur in memory addresses.
917 The amount of increment or decrement are not represented
918 because they can be understood from the machine-mode of the
919 containing MEM. These operations exist in only two cases:
920 1. pushes onto the stack.
921 2. created automatically by the life_analysis pass in flow.c. */
922 DEF_RTL_EXPR(PRE_DEC, "pre_dec", "e", 'a
')
923 DEF_RTL_EXPR(PRE_INC, "pre_inc", "e", 'a
')
924 DEF_RTL_EXPR(POST_DEC, "post_dec", "e", 'a
')
925 DEF_RTL_EXPR(POST_INC, "post_inc", "e", 'a
')
927 /* These binary operations are used to represent generic address
928 side-effects in memory addresses, except for simple incrementation
929 or decrementation which use the above operations. They are
930 created automatically by the life_analysis pass in flow.c.
931 The first operand is a REG which is used as the address.
932 The second operand is an expression that is assigned to the
933 register, either before (PRE_MODIFY) or after (POST_MODIFY)
934 evaluating the address.
935 Currently, the compiler can only handle second operands of the
936 form (plus (reg) (reg)) and (plus (reg) (const_int)), where
937 the first operand of the PLUS has to be the same register as
938 the first operand of the *_MODIFY. */
939 DEF_RTL_EXPR(PRE_MODIFY, "pre_modify", "ee", 'a
')
940 DEF_RTL_EXPR(POST_MODIFY, "post_modify", "ee", 'a
')
942 /* Comparison operations. The ordered comparisons exist in two
943 flavors, signed and unsigned. */
944 DEF_RTL_EXPR(NE, "ne", "ee", '<')
945 DEF_RTL_EXPR(EQ, "eq", "ee", '<')
946 DEF_RTL_EXPR(GE, "ge", "ee", '<')
947 DEF_RTL_EXPR(GT, "gt", "ee", '<')
948 DEF_RTL_EXPR(LE, "le", "ee", '<')
949 DEF_RTL_EXPR(LT, "lt", "ee", '<')
950 DEF_RTL_EXPR(GEU, "geu", "ee", '<')
951 DEF_RTL_EXPR(GTU, "gtu", "ee", '<')
952 DEF_RTL_EXPR(LEU, "leu", "ee", '<')
953 DEF_RTL_EXPR(LTU, "ltu", "ee", '<')
955 /* Additional floating point unordered comparision flavors. */
956 DEF_RTL_EXPR(UNORDERED, "unordered", "ee", '<')
957 DEF_RTL_EXPR(ORDERED, "ordered", "ee", '<')
959 /* These are equivalent to unordered or ... */
960 DEF_RTL_EXPR(UNEQ, "uneq", "ee", '<')
961 DEF_RTL_EXPR(UNGE, "unge", "ee", '<')
962 DEF_RTL_EXPR(UNGT, "ungt", "ee", '<')
963 DEF_RTL_EXPR(UNLE, "unle", "ee", '<')
964 DEF_RTL_EXPR(UNLT, "unlt", "ee", '<')
966 /* This is an ordered NE, ie !UNEQ, ie false for NaN. */
967 DEF_RTL_EXPR(LTGT, "ltgt", "ee", '<')
969 /* Represents the result of sign-extending the sole operand.
970 The machine modes of the operand and of the SIGN_EXTEND expression
971 determine how much sign-extension is going on. */
972 DEF_RTL_EXPR(SIGN_EXTEND, "sign_extend", "e", '1')
974 /* Similar for zero-extension (such as unsigned short to int). */
975 DEF_RTL_EXPR(ZERO_EXTEND, "zero_extend", "e", '1')
977 /* Similar but here the operand has a wider mode. */
978 DEF_RTL_EXPR(TRUNCATE, "truncate", "e", '1')
980 /* Similar for extending floating-point values (such as SFmode to DFmode). */
981 DEF_RTL_EXPR(FLOAT_EXTEND, "float_extend", "e", '1')
982 DEF_RTL_EXPR(FLOAT_TRUNCATE, "float_truncate", "e", '1')
984 /* Conversion of fixed point operand to floating point value. */
985 DEF_RTL_EXPR(FLOAT, "float", "e", '1')
987 /* With fixed-point machine mode:
988 Conversion of floating point operand to fixed point value.
989 Value is defined only when the operand's value is an integer.
990 With floating
-point machine
mode (and operand with same mode
):
991 Operand is rounded toward zero to produce an integer value
992 represented in floating point.
*/
993 DEF_RTL_EXPR(FIX
, "fix", "e", '1')
995 /* Conversion of unsigned fixed point operand to floating point value.
*/
996 DEF_RTL_EXPR(UNSIGNED_FLOAT
, "unsigned_float", "e", '1')
998 /* With fixed
-point machine mode
:
999 Conversion of floating point operand to
*unsigned
* fixed point value.
1000 Value is defined only when the operand
's value is an integer. */
1001 DEF_RTL_EXPR(UNSIGNED_FIX, "unsigned_fix", "e", '1')
1003 /* Absolute value */
1004 DEF_RTL_EXPR(ABS, "abs", "e", '1')
1007 DEF_RTL_EXPR(SQRT, "sqrt", "e", '1')
1009 /* Find first bit that is set.
1010 Value is 1 + number of trailing zeros in the arg.,
1011 or 0 if arg is 0. */
1012 DEF_RTL_EXPR(FFS, "ffs", "e", '1')
1014 /* Reference to a signed bit-field of specified size and position.
1015 Operand 0 is the memory unit (usually SImode or QImode) which
1016 contains the field's first bit. Operand
1 is the width
, in bits.
1017 Operand
2 is the number of bits in the memory unit before the
1018 first bit of this field.
1019 If BITS_BIG_ENDIAN is defined
, the first bit is the msb and
1020 operand
2 counts from the msb of the memory unit.
1021 Otherwise
, the first bit is the lsb and operand
2 counts from
1022 the lsb of the memory unit.
*/
1023 DEF_RTL_EXPR(SIGN_EXTRACT
, "sign_extract", "eee", 'b')
1025 /* Similar for unsigned bit
-field.
*/
1026 DEF_RTL_EXPR(ZERO_EXTRACT
, "zero_extract", "eee", 'b')
1028 /* For RISC machines. These save memory when splitting insns.
*/
1030 /* HIGH are the high
-order bits of a constant expression.
*/
1031 DEF_RTL_EXPR(HIGH, "high", "e", 'o')
1033 /* LO_SUM is the sum of a register and the low
-order bits
1034 of a constant expression.
*/
1035 DEF_RTL_EXPR(LO_SUM
, "lo_sum", "ee", 'o')
1037 /* Header for range information. Operand
0 is the NOTE_INSN_RANGE_BEG insn.
1038 Operand
1 is the NOTE_INSN_RANGE_END insn. Operand
2 is a vector of all of
1039 the registers that can be substituted within this range. Operand
3 is the
1040 number of calls in the range. Operand
4 is the number of insns in the
1041 range. Operand
5 is the unique range number for this range. Operand
6 is
1042 the basic block # of the start of the live range. Operand
7 is the basic
1043 block # of the end of the live range. Operand
8 is the loop depth. Operand
1044 9 is a bitmap of the registers live at the start of the range. Operand
10
1045 is a bitmap of the registers live at the end of the range. Operand
11 is
1046 marker number for the start of the range. Operand
12 is the marker number
1047 for the end of the range.
*/
1048 DEF_RTL_EXPR(RANGE_INFO
, "range_info", "uuEiiiiiibbii", 'x')
1050 /* Registers that can be substituted within the range. Operand
0 is the
1051 original pseudo register number. Operand
1 will be filled in with the
1052 pseudo register the value is copied for the duration of the range. Operand
1053 2 is the number of references within the range to the register. Operand
3
1054 is the number of sets or clobbers of the register in the range. Operand
4
1055 is the number of deaths the register has. Operand
5 is the copy flags that
1056 give the status of whether a copy is needed from the original register to
1057 the new register at the beginning of the range
, or whether a copy from the
1058 new register back to the original at the end of the range. Operand
6 is the
1059 live length. Operand
7 is the number of calls that this register is live
1060 across. Operand
8 is the symbol node of the variable if the register is a
1061 user variable. Operand
9 is the block node that the variable is declared
1062 in if the register is a user variable.
*/
1063 DEF_RTL_EXPR(RANGE_REG
, "range_reg", "iiiiiiiitt", 'x')
1065 /* Information about a local variable
's ranges. Operand 0 is an EXPR_LIST of
1066 the different ranges a variable is in where it is copied to a different
1067 pseudo register. Operand 1 is the block that the variable is declared in.
1068 Operand 2 is the number of distinct ranges. */
1069 DEF_RTL_EXPR(RANGE_VAR, "range_var", "eti", 'x
')
1071 /* Information about the registers that are live at the current point. Operand
1072 0 is the live bitmap. Operand 1 is the original block number. */
1073 DEF_RTL_EXPR(RANGE_LIVE, "range_live", "bi", 'x
')
1075 /* A unary `__builtin_constant_p' expression. These are only emitted
1076 during RTL generation
, and then only if optimize
> 0. They are
1077 eliminated by the first CSE pass.
*/
1078 DEF_RTL_EXPR(CONSTANT_P_RTX
, "constant_p_rtx", "e", 'x')
1080 /* A placeholder for a CALL_INSN which may be turned into a normal call
,
1081 a
sibling (tail
) call or tail recursion.
1083 Immediately after RTL generation
, this placeholder will be replaced
1084 by the insns to perform the call
, sibcall or tail recursion.
1086 This RTX has
4 operands. The first three are lists of instructions to
1087 perform the call as a normal call
, sibling call and tail recursion
1088 respectively. The latter two lists may be NULL
, the first may never
1091 The last operand is the tail recursion CODE_LABEL
, which may be NULL if no
1092 potential tail recursive calls were found.
1094 The tail recursion label is needed so that we can clear LABEL_PRESERVE_P
1095 after we select a call method.
1097 This method of tail
-call elimination is intended to be replaced by
1098 tree
-based optimizations once front
-end conversions are complete.
*/
1099 DEF_RTL_EXPR(CALL_PLACEHOLDER
, "call_placeholder", "uuuu", 'x')
1101 /* Describes a merge operation between two vector values.
1102 Operands
0 and
1 are the vectors to be merged
, operand
2 is a bitmask
1103 that specifies where the parts of the result are taken from. Set bits
1104 indicate operand
0, clear bits indicate operand
1. The parts are defined
1105 by the mode of the vectors.
*/
1106 DEF_RTL_EXPR(VEC_MERGE
, "vec_merge", "eee", 'x')
1108 /* Describes an operation that selects parts of a vector.
1109 Operands
0 is the source vector
, operand
1 is a PARALLEL that contains
1110 a CONST_INT for each of the subparts of the result vector
, giving the
1111 number of the source subpart that should be stored into it.
*/
1112 DEF_RTL_EXPR(VEC_SELECT
, "vec_select", "ee", 'x')
1114 /* Describes a vector concat operation. Operands
0 and
1 are the source
1115 vectors
, the result is a vector that is as long as operands
0 and
1
1116 combined and is the concatenation of the two source vectors.
*/
1117 DEF_RTL_EXPR(VEC_CONCAT
, "vec_concat", "ee", 'x')
1119 /* Describes an operation that converts a small vector into a larger one by
1120 duplicating the input values. The output vector mode must have the same
1121 submodes as the input vector mode
, and the number of output parts must be
1122 an integer multiple of the number of input parts.
*/
1123 DEF_RTL_EXPR(VEC_DUPLICATE
, "vec_duplicate", "e", 'x')
1125 /* Addition with signed saturation
*/
1126 DEF_RTL_EXPR(SS_PLUS
, "ss_plus", "ee", 'c')
1128 /* Addition with unsigned saturation
*/
1129 DEF_RTL_EXPR(US_PLUS
, "us_plus", "ee", 'c')
1131 /* Operand
0 minus operand
1, with signed saturation.
*/
1132 DEF_RTL_EXPR(SS_MINUS
, "ss_minus", "ee", '2')
1134 /* Operand
0 minus operand
1, with unsigned saturation.
*/
1135 DEF_RTL_EXPR(US_MINUS
, "us_minus", "ee", '2')
1137 /* Signed saturating truncate.
*/
1138 DEF_RTL_EXPR(SS_TRUNCATE
, "ss_truncate", "e", '1')
1140 /* Unsigned saturating truncate.
*/
1141 DEF_RTL_EXPR(US_TRUNCATE
, "us_truncate", "e", '1')
1143 /* The SSA phi operator.
1145 The argument is a vector of
2N rtxes. Element
2N
+1 is a CONST_INT
1146 containing the block number of the predecessor through which control
1147 has passed when the register at element
2N is used.
1149 Note that PHI may only appear at the beginning of a basic block.
1151 ??? There may be multiple PHI insns
, but they are all evaluated
1152 in parallel. This probably ought to be changed to use a real
1153 PARALLEL
, as that would be less confusing and more in the spirit
1154 of canonical RTL. It is
, however
, easier to manipulate this way.
*/
1155 DEF_RTL_EXPR(PHI
, "phi", "E", 'x')