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,
6 Free Software Foundation, Inc.
8 This file is part of GCC.
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
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
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
26 /* Expression definitions and descriptions for all targets are in this file.
27 Some will not be used for some targets.
29 The fields in the cpp macro call "DEF_RTL_EXPR()"
30 are used to create declarations in the C source of the compiler.
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.
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.
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
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:
51 an rtx code that can be used to represent a constant object
54 an rtx code that can be used to represent an object (e.g, REG, MEM)
56 an rtx code for a comparison (e.g, LT, GT)
58 an rtx code for a commutative comparison (e.g, EQ, NE, ORDERED)
60 an rtx code for a unary arithmetic expression (e.g, NEG, NOT)
62 an rtx code for a commutative binary operation (e.g,, PLUS, MULT)
64 an rtx code for a non-bitfield three input operation (IF_THEN_ELSE)
66 an rtx code for a non-commutative binary operation (e.g., MINUS, DIV)
68 an rtx code for a bit-field operation (ZERO_EXTRACT, SIGN_EXTRACT)
70 an rtx code for a machine insn (INSN, JUMP_INSN, CALL_INSN)
72 an rtx code for something that matches in insns (e.g, MATCH_DUP)
74 an rtx code for autoincrement addressing modes (e.g. POST_DEC)
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. */
81 /* Unknown, or no such operation; the enumeration constant should have
83 DEF_RTL_EXPR(UNKNOWN, "UnKnown", "*", RTX_EXTRA)
85 /* ---------------------------------------------------------------------
86 Expressions used in constructing lists.
87 --------------------------------------------------------------------- */
89 /* a linked list of expressions */
90 DEF_RTL_EXPR(EXPR_LIST, "expr_list", "ee", RTX_EXTRA)
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)
96 /* a linked list of dependencies.
97 The insns are represented in print by their uids.
98 Operand 2 is the status of a dependence (see sched-int.h for more). */
99 DEF_RTL_EXPR(DEPS_LIST, "deps_list", "uei", RTX_EXTRA)
101 /* SEQUENCE appears in the result of a `gen_...' function
102 for a DEFINE_EXPAND that wants to make several insns.
103 Its elements are the bodies of the insns that should be made.
104 `emit_insn
' takes the SEQUENCE apart and makes separate insns. */
105 DEF_RTL_EXPR(SEQUENCE, "sequence", "E", RTX_EXTRA)
107 /* Refers to the address of its argument. This is only used in alias.c. */
108 DEF_RTL_EXPR(ADDRESS, "address", "e", RTX_MATCH)
110 /* ----------------------------------------------------------------------
111 Expression types used for things in the instruction chain.
113 All formats must start with "iuu" to handle the chain.
114 Each insn expression holds an rtl instruction and its semantics
115 during back-end processing.
116 See macros's in
"rtl.h" for the meaning of each rtx
->u.fld
[].
118 ---------------------------------------------------------------------- */
120 /* An instruction that cannot jump.
*/
121 DEF_RTL_EXPR(INSN
, "insn", "iuuBieiee", RTX_INSN
)
123 /* An instruction that can possibly jump.
124 Fields ( rtx
->u.fld
[] ) have exact same meaning as INSN
's. */
125 DEF_RTL_EXPR(JUMP_INSN, "jump_insn", "iuuBieiee0", RTX_INSN)
127 /* An instruction that can possibly call a subroutine
128 but which will not change which instruction comes next
129 in the current function.
130 Field ( rtx->u.fld[9] ) is CALL_INSN_FUNCTION_USAGE.
131 All other fields ( rtx->u.fld[] ) have exact same meaning as INSN's.
*/
132 DEF_RTL_EXPR(CALL_INSN
, "call_insn", "iuuBieieee", RTX_INSN
)
134 /* A marker that indicates that control will not flow through.
*/
135 DEF_RTL_EXPR(BARRIER
, "barrier", "iuu000000", RTX_EXTRA
)
137 /* Holds a label that is followed by instructions.
139 4: is used in jump.c for the use
-count of the label.
140 5: is used in flow.c to point to the chain of label_ref
's to this label.
141 6: is a number that is unique in the entire compilation.
142 APPLE LOCAL begin for-fsf-4_4 3274130 5295549
143 7: is the user-given name of the label, if any.
144 8: is the alignment of the label, made up of two parts,
145 LABEL_ALIGNMENT and LABEL_MAX_SKIP. */
146 DEF_RTL_EXPR(CODE_LABEL, "code_label", "iuuB00isi", RTX_EXTRA)
148 /* APPLE LOCAL end for-fsf-4_4 3274130 5295549 */ \
149 #ifdef USE_MAPPED_LOCATION
150 /* Say where in the code a source line starts, for symbol table's sake.
152 4: unused if line number
> 0, note
-specific data otherwise.
153 5: line number if
> 0, enum note_insn otherwise.
154 6: CODE_LABEL_NUMBER if line number
== NOTE_INSN_DELETED_LABEL.
*/
156 /* Say where in the code a source line starts
, for symbol table
's sake.
158 4: filename, if line number > 0, note-specific data otherwise.
159 5: line number if > 0, enum note_insn otherwise.
160 6: unique number if line number == note_insn_deleted_label. */
162 DEF_RTL_EXPR(NOTE, "note", "iuuB0ni", RTX_EXTRA)
164 /* ----------------------------------------------------------------------
165 Top level constituents of INSN, JUMP_INSN and CALL_INSN.
166 ---------------------------------------------------------------------- */
168 /* Conditionally execute code.
169 Operand 0 is the condition that if true, the code is executed.
170 Operand 1 is the code to be executed (typically a SET).
172 Semantics are that there are no side effects if the condition
173 is false. This pattern is created automatically by the if_convert
174 pass run after reload or by target-specific splitters. */
175 DEF_RTL_EXPR(COND_EXEC, "cond_exec", "ee", RTX_EXTRA)
177 /* Several operations to be done in parallel (perhaps under COND_EXEC). */
178 DEF_RTL_EXPR(PARALLEL, "parallel", "E", RTX_EXTRA)
180 /* A string that is passed through to the assembler as input.
181 One can obviously pass comments through by using the
182 assembler comment syntax.
183 These occur in an insn all by themselves as the PATTERN.
184 They also appear inside an ASM_OPERANDS
185 as a convenient way to hold a string. */
186 DEF_RTL_EXPR(ASM_INPUT, "asm_input", "s", RTX_EXTRA)
188 #ifdef USE_MAPPED_LOCATION
189 /* An assembler instruction with operands.
190 1st operand is the instruction template.
191 2nd operand is the constraint for the output.
192 3rd operand is the number of the output this expression refers to.
193 When an insn stores more than one value, a separate ASM_OPERANDS
194 is made for each output; this integer distinguishes them.
195 4th is a vector of values of input operands.
196 5th is a vector of modes and constraints for the input operands.
197 Each element is an ASM_INPUT containing a constraint string
198 and whose mode indicates the mode of the input operand.
199 6th is the source line number. */
200 DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEi", RTX_EXTRA)
202 /* An assembler instruction with operands.
203 1st operand is the instruction template.
204 2nd operand is the constraint for the output.
205 3rd operand is the number of the output this expression refers to.
206 When an insn stores more than one value, a separate ASM_OPERANDS
207 is made for each output; this integer distinguishes them.
208 4th is a vector of values of input operands.
209 5th is a vector of modes and constraints for the input operands.
210 Each element is an ASM_INPUT containing a constraint string
211 and whose mode indicates the mode of the input operand.
212 6th is the name of the containing source file.
213 7th is the source line number. */
214 DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEsi", RTX_EXTRA)
217 /* A machine-specific operation.
218 1st operand is a vector of operands being used by the operation so that
219 any needed reloads can be done.
220 2nd operand is a unique value saying which of a number of machine-specific
221 operations is to be performed.
222 (Note that the vector must be the first operand because of the way that
223 genrecog.c record positions within an insn.)
224 This can occur all by itself in a PATTERN, as a component of a PARALLEL,
225 or inside an expression. */
226 DEF_RTL_EXPR(UNSPEC, "unspec", "Ei", RTX_EXTRA)
228 /* Similar, but a volatile operation and one which may trap. */
229 DEF_RTL_EXPR(UNSPEC_VOLATILE, "unspec_volatile", "Ei", RTX_EXTRA)
231 /* Vector of addresses, stored as full words. */
232 /* Each element is a LABEL_REF to a CODE_LABEL whose address we want. */
233 DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", RTX_EXTRA)
235 /* Vector of address differences X0 - BASE, X1 - BASE, ...
236 First operand is BASE; the vector contains the X's.
237 The machine mode of this rtx says how much space to leave
238 for each difference and is adjusted by branch shortening if
239 CASE_VECTOR_SHORTEN_MODE is defined.
240 The third and fourth operands store the target labels with the
241 minimum and maximum addresses respectively.
242 The fifth operand stores flags for use by branch shortening.
243 Set at the start of shorten_branches
:
244 min_align
: the minimum alignment for any of the target labels.
245 base_after_vec
: true iff BASE is after the ADDR_DIFF_VEC.
246 min_after_vec
: true iff minimum addr target label is after the ADDR_DIFF_VEC.
247 max_after_vec
: true iff maximum addr target label is after the ADDR_DIFF_VEC.
248 min_after_base
: true iff minimum address target label is after BASE.
249 max_after_base
: true iff maximum address target label is after BASE.
250 Set by the actual branch shortening process
:
251 offset_unsigned
: true iff offsets have to be treated as unsigned.
252 scale
: scaling that is necessary to make offsets fit into the mode.
254 The third
, fourth and fifth operands are only valid when
255 CASE_VECTOR_SHORTEN_MODE is defined
, and only in an optimizing
258 DEF_RTL_EXPR(ADDR_DIFF_VEC
, "addr_diff_vec", "eEee0", RTX_EXTRA
)
260 /* Memory prefetch
, with attributes supported on some targets.
261 Operand
1 is the address of the memory to fetch.
262 Operand
2 is
1 for a write access
, 0 otherwise.
263 Operand
3 is the level of temporal locality
; 0 means there is no
264 temporal locality and
1, 2, and
3 are for increasing levels of temporal
267 The attributes specified by operands
2 and
3 are ignored for targets
268 whose prefetch instructions do not support them.
*/
269 DEF_RTL_EXPR(PREFETCH
, "prefetch", "eee", RTX_EXTRA
)
271 /* ----------------------------------------------------------------------
272 At the top level of an
instruction (perhaps under PARALLEL
).
273 ---------------------------------------------------------------------- */
276 Operand
1 is the
location (REG
, MEM
, PC
, CC0 or whatever
) assigned to.
277 Operand
2 is the value stored there.
278 ALL assignment must use
SET.
279 Instructions that do multiple assignments must use multiple
SET,
281 DEF_RTL_EXPR(SET, "set", "ee", RTX_EXTRA
)
283 /* Indicate something is used in a way that we don
't want to explain.
284 For example, subroutine calls will use the register
285 in which the static chain is passed. */
286 DEF_RTL_EXPR(USE, "use", "e", RTX_EXTRA)
288 /* Indicate something is clobbered in a way that we don't want to explain.
289 For example
, subroutine calls will clobber some physical registers
290 (the ones that are by convention not saved
).
*/
291 DEF_RTL_EXPR(CLOBBER
, "clobber", "e", RTX_EXTRA
)
293 /* Call a subroutine.
294 Operand
1 is the address to call.
295 Operand
2 is the number of arguments.
*/
297 DEF_RTL_EXPR(CALL
, "call", "ee", RTX_EXTRA
)
299 /* Return from a subroutine.
*/
301 DEF_RTL_EXPR(RETURN, "return", "", RTX_EXTRA
)
304 Operand
1 is the condition.
305 Operand
2 is the trap code.
306 For an unconditional trap
, make the
condition (const_int
1).
*/
307 DEF_RTL_EXPR(TRAP_IF
, "trap_if", "ee", RTX_EXTRA
)
309 /* Placeholder for _Unwind_Resume before we know if a function call
310 or a branch is needed. Operand
1 is the exception region from
311 which control is flowing.
*/
312 DEF_RTL_EXPR(RESX
, "resx", "i", RTX_EXTRA
)
314 /* ----------------------------------------------------------------------
315 Primitive values for use in expressions.
316 ---------------------------------------------------------------------- */
318 /* numeric integer constant
*/
319 DEF_RTL_EXPR(CONST_INT
, "const_int", "w", RTX_CONST_OBJ
)
321 /* numeric floating point constant.
322 Operands hold the value. They are all
'w' and there may be from
2 to
6;
324 DEF_RTL_EXPR(CONST_DOUBLE
, "const_double", CONST_DOUBLE_FORMAT
, RTX_CONST_OBJ
)
326 /* Describes a vector constant.
*/
327 DEF_RTL_EXPR(CONST_VECTOR
, "const_vector", "E", RTX_CONST_OBJ
)
329 /* String constant. Used for attributes in machine descriptions and
330 for special cases in DWARF2 debug output.
NOT used for source
-
331 language string constants.
*/
332 DEF_RTL_EXPR(CONST_STRING
, "const_string", "s", RTX_OBJ
)
334 /* This is used to encapsulate an expression whose value is constant
335 (such as the sum of a SYMBOL_REF and a CONST_INT
) so that it will be
336 recognized as a constant operand rather than by arithmetic instructions.
*/
338 DEF_RTL_EXPR(CONST, "const", "e", RTX_CONST_OBJ
)
340 /* program counter. Ordinary jumps are represented
341 by a
SET whose first operand
is (PC
).
*/
342 DEF_RTL_EXPR(PC
, "pc", "", RTX_OBJ
)
344 /* Used in the cselib routines to describe a value. Objects of this
345 kind are only allocated in cselib.c
, in an alloc pool instead of
346 in GC memory. The only operand of a VALUE is a cselib_val_struct.
*/
347 DEF_RTL_EXPR(VALUE
, "value", "0", RTX_OBJ
)
349 /* A register. The
"operand" is the register number
, accessed with
350 the REGNO macro. If this number is less than FIRST_PSEUDO_REGISTER
351 than a hardware register is being referred to. The second operand
352 holds the original register number
- this will be different for a
353 pseudo register that got turned into a hard register. The third
354 operand points to a reg_attrs structure.
355 This rtx needs to have as
many (or more
) fields as a MEM
, since we
356 can change REG rtx
's into MEMs during reload. */
357 DEF_RTL_EXPR(REG, "reg", "i00", RTX_OBJ)
359 /* A scratch register. This represents a register used only within a
360 single insn. It will be turned into a REG during register allocation
361 or reload unless the constraint indicates that the register won't be
362 needed
, in which case it can remain a SCRATCH. This code is
363 marked as having one operand so it can be turned into a REG.
*/
364 DEF_RTL_EXPR(SCRATCH
, "scratch", "0", RTX_OBJ
)
366 /* One word of a multi
-word value.
367 The first operand is the complete value
; the second says which word.
368 The WORDS_BIG_ENDIAN flag controls whether word number
0
369 (as numbered in a SUBREG
) is the most or least significant word.
371 This is also used to refer to a value in a different machine mode.
372 For example
, it can be used to refer to a SImode value as if it were
373 Qimode
, or vice versa. Then the word number is always
0.
*/
374 DEF_RTL_EXPR(SUBREG
, "subreg", "ei", RTX_EXTRA
)
376 /* This one
-argument rtx is used for move instructions
377 that are guaranteed to alter only the low part of a destination.
378 Thus
, (SET (SUBREG
:HI (REG...
)) (MEM
:HI ...
))
379 has an unspecified effect on the high part of REG
,
380 but (SET (STRICT_LOW_PART (SUBREG
:HI (REG...
))) (MEM
:HI ...
))
381 is guaranteed to alter only the bits of REG that are in HImode.
383 The actual instruction used is probably the same in both cases
,
384 but the register constraints may be tighter when STRICT_LOW_PART
387 DEF_RTL_EXPR(STRICT_LOW_PART
, "strict_low_part", "e", RTX_EXTRA
)
389 /* (CONCAT a b
) represents the virtual concatenation of a and b
390 to make a value that has as many bits as a and b put together.
391 This is used for complex values. Normally it appears only
392 in DECL_RTLs and during RTL generation
, but not in the insn chain.
*/
393 DEF_RTL_EXPR(CONCAT
, "concat", "ee", RTX_OBJ
)
395 /* A memory location
; operand is the address. The second operand is the
396 alias set to which this MEM belongs. We use `
0' instead of `w' for this
397 field so that the field need not be specified in machine descriptions.
*/
398 DEF_RTL_EXPR(MEM
, "mem", "e0", RTX_OBJ
)
400 /* Reference to an assembler label in the code for this function.
401 The operand is a CODE_LABEL found in the insn chain.
*/
402 DEF_RTL_EXPR(LABEL_REF
, "label_ref", "u", RTX_CONST_OBJ
)
404 /* Reference to a named label
:
405 Operand
0: label name
406 Operand
1: flags (see SYMBOL_FLAG_
* in rtl.h
)
407 Operand
2: tree from which this symbol is derived
, or null.
408 This is either a DECL node
, or some kind of constant.
*/
409 DEF_RTL_EXPR(SYMBOL_REF
, "symbol_ref", "s00", RTX_CONST_OBJ
)
411 /* The condition code register is represented
, in our imagination
,
412 as a register holding a value that can be compared to zero.
413 In fact
, the machine has already compared them and recorded the
414 results
; but instructions that look at the condition code
415 pretend to be looking at the entire value and comparing it.
*/
416 DEF_RTL_EXPR(CC0
, "cc0", "", RTX_OBJ
)
418 /* ----------------------------------------------------------------------
419 Expressions for operators in an rtl pattern
420 ---------------------------------------------------------------------- */
422 /* if_then_else. This is used in representing ordinary
423 conditional jump instructions.
428 DEF_RTL_EXPR(IF_THEN_ELSE
, "if_then_else", "eee", RTX_TERNARY
)
430 /* Comparison
, produces a condition code result.
*/
431 DEF_RTL_EXPR(COMPARE
, "compare", "ee", RTX_BIN_ARITH
)
434 DEF_RTL_EXPR(PLUS
, "plus", "ee", RTX_COMM_ARITH
)
436 /* Operand
0 minus operand
1.
*/
437 DEF_RTL_EXPR(MINUS
, "minus", "ee", RTX_BIN_ARITH
)
439 /* Minus operand
0.
*/
440 DEF_RTL_EXPR(NEG
, "neg", "e", RTX_UNARY
)
442 DEF_RTL_EXPR(MULT
, "mult", "ee", RTX_COMM_ARITH
)
444 /* Operand
0 divided by operand
1.
*/
445 DEF_RTL_EXPR(DIV, "div", "ee", RTX_BIN_ARITH
)
446 /* Remainder of operand
0 divided by operand
1.
*/
447 DEF_RTL_EXPR(MOD, "mod", "ee", RTX_BIN_ARITH
)
449 /* Unsigned divide and remainder.
*/
450 DEF_RTL_EXPR(UDIV
, "udiv", "ee", RTX_BIN_ARITH
)
451 DEF_RTL_EXPR(UMOD
, "umod", "ee", RTX_BIN_ARITH
)
453 /* Bitwise operations.
*/
454 DEF_RTL_EXPR(AND, "and", "ee", RTX_COMM_ARITH
)
455 DEF_RTL_EXPR(IOR
, "ior", "ee", RTX_COMM_ARITH
)
456 DEF_RTL_EXPR(XOR
, "xor", "ee", RTX_COMM_ARITH
)
457 DEF_RTL_EXPR(NOT, "not", "e", RTX_UNARY
)
460 0: value to be shifted.
461 1: number of bits.
*/
462 DEF_RTL_EXPR(ASHIFT
, "ashift", "ee", RTX_BIN_ARITH
) /* shift left
*/
463 DEF_RTL_EXPR(ROTATE
, "rotate", "ee", RTX_BIN_ARITH
) /* rotate left
*/
464 DEF_RTL_EXPR(ASHIFTRT
, "ashiftrt", "ee", RTX_BIN_ARITH
) /* arithmetic shift right
*/
465 DEF_RTL_EXPR(LSHIFTRT
, "lshiftrt", "ee", RTX_BIN_ARITH
) /* logical shift right
*/
466 DEF_RTL_EXPR(ROTATERT
, "rotatert", "ee", RTX_BIN_ARITH
) /* rotate right
*/
468 /* Minimum and maximum values of two operands. We need both signed and
469 unsigned forms.
(We cannot use
MIN for SMIN because it conflicts
470 with a macro of the same name.
) The signed variants should be used
471 with floating point. Further
, if both operands are zeros
, or if either
472 operand is NaN
, then it is unspecified which of the two operands is
473 returned as the result.
*/
475 DEF_RTL_EXPR(SMIN
, "smin", "ee", RTX_COMM_ARITH
)
476 DEF_RTL_EXPR(SMAX
, "smax", "ee", RTX_COMM_ARITH
)
477 DEF_RTL_EXPR(UMIN
, "umin", "ee", RTX_COMM_ARITH
)
478 DEF_RTL_EXPR(UMAX
, "umax", "ee", RTX_COMM_ARITH
)
480 /* These unary operations are used to represent incrementation
481 and decrementation as they occur in memory addresses.
482 The amount of increment or decrement are not represented
483 because they can be understood from the machine
-mode of the
484 containing MEM. These operations exist in only two cases
:
485 1. pushes onto the stack.
486 2. created automatically by the life_analysis pass in flow.c.
*/
487 DEF_RTL_EXPR(PRE_DEC
, "pre_dec", "e", RTX_AUTOINC
)
488 DEF_RTL_EXPR(PRE_INC
, "pre_inc", "e", RTX_AUTOINC
)
489 DEF_RTL_EXPR(POST_DEC
, "post_dec", "e", RTX_AUTOINC
)
490 DEF_RTL_EXPR(POST_INC
, "post_inc", "e", RTX_AUTOINC
)
492 /* These binary operations are used to represent generic address
493 side
-effects in memory addresses
, except for simple incrementation
494 or decrementation which use the above operations. They are
495 created automatically by the life_analysis pass in flow.c.
496 The first operand is a REG which is used as the address.
497 The second operand is an expression that is assigned to the
498 register
, either
before (PRE_MODIFY
) or
after (POST_MODIFY
)
499 evaluating the address.
500 Currently
, the compiler can only handle second operands of the
501 form (plus (reg
) (reg
)) and (plus (reg
) (const_int
)), where
502 the first operand of the PLUS has to be the same register as
503 the first operand of the
*_MODIFY.
*/
504 DEF_RTL_EXPR(PRE_MODIFY
, "pre_modify", "ee", RTX_AUTOINC
)
505 DEF_RTL_EXPR(POST_MODIFY
, "post_modify", "ee", RTX_AUTOINC
)
507 /* Comparison operations. The ordered comparisons exist in two
508 flavors
, signed and unsigned.
*/
509 DEF_RTL_EXPR(NE
, "ne", "ee", RTX_COMM_COMPARE
)
510 DEF_RTL_EXPR(EQ
, "eq", "ee", RTX_COMM_COMPARE
)
511 DEF_RTL_EXPR(GE
, "ge", "ee", RTX_COMPARE
)
512 DEF_RTL_EXPR(GT
, "gt", "ee", RTX_COMPARE
)
513 DEF_RTL_EXPR(LE
, "le", "ee", RTX_COMPARE
)
514 DEF_RTL_EXPR(LT
, "lt", "ee", RTX_COMPARE
)
515 DEF_RTL_EXPR(GEU
, "geu", "ee", RTX_COMPARE
)
516 DEF_RTL_EXPR(GTU
, "gtu", "ee", RTX_COMPARE
)
517 DEF_RTL_EXPR(LEU
, "leu", "ee", RTX_COMPARE
)
518 DEF_RTL_EXPR(LTU
, "ltu", "ee", RTX_COMPARE
)
520 /* Additional floating point unordered comparison flavors.
*/
521 DEF_RTL_EXPR(UNORDERED
, "unordered", "ee", RTX_COMM_COMPARE
)
522 DEF_RTL_EXPR(ORDERED
, "ordered", "ee", RTX_COMM_COMPARE
)
524 /* These are equivalent to unordered or ...
*/
525 DEF_RTL_EXPR(UNEQ
, "uneq", "ee", RTX_COMM_COMPARE
)
526 DEF_RTL_EXPR(UNGE
, "unge", "ee", RTX_COMPARE
)
527 DEF_RTL_EXPR(UNGT
, "ungt", "ee", RTX_COMPARE
)
528 DEF_RTL_EXPR(UNLE
, "unle", "ee", RTX_COMPARE
)
529 DEF_RTL_EXPR(UNLT
, "unlt", "ee", RTX_COMPARE
)
531 /* This is an ordered NE
, ie
!UNEQ
, ie false for NaN.
*/
532 DEF_RTL_EXPR(LTGT
, "ltgt", "ee", RTX_COMM_COMPARE
)
534 /* Represents the result of sign
-extending the sole operand.
535 The machine modes of the operand and of the SIGN_EXTEND expression
536 determine how much sign
-extension is going on.
*/
537 DEF_RTL_EXPR(SIGN_EXTEND
, "sign_extend", "e", RTX_UNARY
)
539 /* Similar for zero
-extension (such as unsigned short to int
).
*/
540 DEF_RTL_EXPR(ZERO_EXTEND
, "zero_extend", "e", RTX_UNARY
)
542 /* Similar but here the operand has a wider mode.
*/
543 DEF_RTL_EXPR(TRUNCATE
, "truncate", "e", RTX_UNARY
)
545 /* Similar for extending floating
-point
values (such as SFmode to DFmode
).
*/
546 DEF_RTL_EXPR(FLOAT_EXTEND
, "float_extend", "e", RTX_UNARY
)
547 DEF_RTL_EXPR(FLOAT_TRUNCATE
, "float_truncate", "e", RTX_UNARY
)
549 /* Conversion of fixed point operand to floating point value.
*/
550 DEF_RTL_EXPR(FLOAT, "float", "e", RTX_UNARY
)
552 /* With fixed
-point machine mode
:
553 Conversion of floating point operand to fixed point value.
554 Value is defined only when the operand
's value is an integer.
555 With floating-point machine mode (and operand with same mode):
556 Operand is rounded toward zero to produce an integer value
557 represented in floating point. */
558 DEF_RTL_EXPR(FIX, "fix", "e", RTX_UNARY)
560 /* Conversion of unsigned fixed point operand to floating point value. */
561 DEF_RTL_EXPR(UNSIGNED_FLOAT, "unsigned_float", "e", RTX_UNARY)
563 /* With fixed-point machine mode:
564 Conversion of floating point operand to *unsigned* fixed point value.
565 Value is defined only when the operand's value is an integer.
*/
566 DEF_RTL_EXPR(UNSIGNED_FIX
, "unsigned_fix", "e", RTX_UNARY
)
569 DEF_RTL_EXPR(ABS, "abs", "e", RTX_UNARY
)
572 DEF_RTL_EXPR(SQRT
, "sqrt", "e", RTX_UNARY
)
575 DEF_RTL_EXPR(BSWAP
, "bswap", "e", RTX_UNARY
)
577 /* Find first bit that is set.
578 Value is
1 + number of trailing zeros in the arg.
,
580 DEF_RTL_EXPR(FFS
, "ffs", "e", RTX_UNARY
)
582 /* Count leading zeros.
*/
583 DEF_RTL_EXPR(CLZ
, "clz", "e", RTX_UNARY
)
585 /* Count trailing zeros.
*/
586 DEF_RTL_EXPR(CTZ
, "ctz", "e", RTX_UNARY
)
588 /* Population
count (number of
1 bits
).
*/
589 DEF_RTL_EXPR(POPCOUNT
, "popcount", "e", RTX_UNARY
)
591 /* Population
parity (number of
1 bits modulo
2).
*/
592 DEF_RTL_EXPR(PARITY
, "parity", "e", RTX_UNARY
)
594 /* Reference to a signed bit
-field of specified size and position.
595 Operand
0 is the memory
unit (usually SImode or QImode
) which
596 contains the field
's first bit. Operand 1 is the width, in bits.
597 Operand 2 is the number of bits in the memory unit before the
598 first bit of this field.
599 If BITS_BIG_ENDIAN is defined, the first bit is the msb and
600 operand 2 counts from the msb of the memory unit.
601 Otherwise, the first bit is the lsb and operand 2 counts from
602 the lsb of the memory unit.
603 This kind of expression can not appear as an lvalue in RTL. */
604 DEF_RTL_EXPR(SIGN_EXTRACT, "sign_extract", "eee", RTX_BITFIELD_OPS)
606 /* Similar for unsigned bit-field.
607 But note! This kind of expression _can_ appear as an lvalue. */
608 DEF_RTL_EXPR(ZERO_EXTRACT, "zero_extract", "eee", RTX_BITFIELD_OPS)
610 /* For RISC machines. These save memory when splitting insns. */
612 /* HIGH are the high-order bits of a constant expression. */
613 DEF_RTL_EXPR(HIGH, "high", "e", RTX_CONST_OBJ)
615 /* LO_SUM is the sum of a register and the low-order bits
616 of a constant expression. */
617 DEF_RTL_EXPR(LO_SUM, "lo_sum", "ee", RTX_OBJ)
619 /* Describes a merge operation between two vector values.
620 Operands 0 and 1 are the vectors to be merged, operand 2 is a bitmask
621 that specifies where the parts of the result are taken from. Set bits
622 indicate operand 0, clear bits indicate operand 1. The parts are defined
623 by the mode of the vectors. */
624 DEF_RTL_EXPR(VEC_MERGE, "vec_merge", "eee", RTX_TERNARY)
626 /* Describes an operation that selects parts of a vector.
627 Operands 0 is the source vector, operand 1 is a PARALLEL that contains
628 a CONST_INT for each of the subparts of the result vector, giving the
629 number of the source subpart that should be stored into it. */
630 DEF_RTL_EXPR(VEC_SELECT, "vec_select", "ee", RTX_BIN_ARITH)
632 /* Describes a vector concat operation. Operands 0 and 1 are the source
633 vectors, the result is a vector that is as long as operands 0 and 1
634 combined and is the concatenation of the two source vectors. */
635 DEF_RTL_EXPR(VEC_CONCAT, "vec_concat", "ee", RTX_BIN_ARITH)
637 /* Describes an operation that converts a small vector into a larger one by
638 duplicating the input values. The output vector mode must have the same
639 submodes as the input vector mode, and the number of output parts must be
640 an integer multiple of the number of input parts. */
641 DEF_RTL_EXPR(VEC_DUPLICATE, "vec_duplicate", "e", RTX_UNARY)
643 /* Addition with signed saturation */
644 DEF_RTL_EXPR(SS_PLUS, "ss_plus", "ee", RTX_COMM_ARITH)
646 /* Addition with unsigned saturation */
647 DEF_RTL_EXPR(US_PLUS, "us_plus", "ee", RTX_COMM_ARITH)
649 /* Operand 0 minus operand 1, with signed saturation. */
650 DEF_RTL_EXPR(SS_MINUS, "ss_minus", "ee", RTX_BIN_ARITH)
652 /* Negation with signed saturation. */
653 DEF_RTL_EXPR(SS_NEG, "ss_neg", "e", RTX_UNARY)
655 /* Shift left with signed saturation. */
656 DEF_RTL_EXPR(SS_ASHIFT, "ss_ashift", "ee", RTX_BIN_ARITH)
658 /* Operand 0 minus operand 1, with unsigned saturation. */
659 DEF_RTL_EXPR(US_MINUS, "us_minus", "ee", RTX_BIN_ARITH)
661 /* Signed saturating truncate. */
662 DEF_RTL_EXPR(SS_TRUNCATE, "ss_truncate", "e", RTX_UNARY)
664 /* Unsigned saturating truncate. */
665 DEF_RTL_EXPR(US_TRUNCATE, "us_truncate", "e", RTX_UNARY)
667 /* Information about the variable and its location. */
668 DEF_RTL_EXPR(VAR_LOCATION, "var_location", "te", RTX_EXTRA)
670 /* All expressions from this point forward appear only in machine
672 #ifdef GENERATOR_FILE
674 /* Include a secondary machine-description file at this point. */
675 DEF_RTL_EXPR(INCLUDE, "include", "s", RTX_EXTRA)
677 /* Pattern-matching operators: */
679 /* Use the function named by the second arg (the string)
680 as a predicate; if matched, store the structure that was matched
681 in the operand table at index specified by the first arg (the integer).
682 If the second arg is the null string, the structure is just stored.
684 A third string argument indicates to the register allocator restrictions
685 on where the operand can be allocated.
687 If the target needs no restriction on any instruction this field should
690 The string is prepended by:
691 '=' to indicate the operand is only written to.
692 '+' to indicate the operand is both read and written to.
694 Each character in the string represents an allocable class for an operand.
695 'g
' indicates the operand can be any valid class.
696 'i
' indicates the operand can be immediate (in the instruction) data.
697 'r
' indicates the operand can be in a register.
698 'm
' indicates the operand can be in memory.
699 'o
' a subset of the 'm
' class. Those memory addressing modes that
700 can be offset at compile time (have a constant added to them).
702 Other characters indicate target dependent operand classes and
703 are described in each target's machine description.
705 For instructions with more than one operand
, sets of classes can be
706 separated by a comma to indicate the appropriate multi
-operand constraints.
707 There must be a
1 to
1 correspondence between these sets of classes in
708 all operands for an instruction.
710 DEF_RTL_EXPR(MATCH_OPERAND
, "match_operand", "iss", RTX_MATCH
)
712 /* Match a SCRATCH or a register. When used to generate rtl
, a
713 SCRATCH is generated. As for MATCH_OPERAND
, the mode specifies
714 the desired mode and the first argument is the operand number.
715 The second argument is the constraint.
*/
716 DEF_RTL_EXPR(MATCH_SCRATCH
, "match_scratch", "is", RTX_MATCH
)
718 /* Apply a predicate
, AND match recursively the operands of the rtx.
719 Operand
0 is the operand
-number
, as in match_operand.
720 Operand
1 is a predicate to
apply (as a string
, a function name
).
721 Operand
2 is a vector of expressions
, each of which must match
722 one subexpression of the rtx this construct is matching.
*/
723 DEF_RTL_EXPR(MATCH_OPERATOR
, "match_operator", "isE", RTX_MATCH
)
725 /* Match a PARALLEL of arbitrary length. The predicate is applied
726 to the PARALLEL and the initial expressions in the PARALLEL are matched.
727 Operand
0 is the operand
-number
, as in match_operand.
728 Operand
1 is a predicate to apply to the PARALLEL.
729 Operand
2 is a vector of expressions
, each of which must match the
730 corresponding element in the PARALLEL.
*/
731 DEF_RTL_EXPR(MATCH_PARALLEL
, "match_parallel", "isE", RTX_MATCH
)
733 /* Match only something equal to what is stored in the operand table
734 at the index specified by the argument. Use with MATCH_OPERAND.
*/
735 DEF_RTL_EXPR(MATCH_DUP
, "match_dup", "i", RTX_MATCH
)
737 /* Match only something equal to what is stored in the operand table
738 at the index specified by the argument. Use with MATCH_OPERATOR.
*/
739 DEF_RTL_EXPR(MATCH_OP_DUP
, "match_op_dup", "iE", RTX_MATCH
)
741 /* Match only something equal to what is stored in the operand table
742 at the index specified by the argument. Use with MATCH_PARALLEL.
*/
743 DEF_RTL_EXPR(MATCH_PAR_DUP
, "match_par_dup", "iE", RTX_MATCH
)
745 /* Appears only in define_predicate
/define_special_predicate
746 expressions. Evaluates true only if the operand has an RTX code
747 from the set given by the
argument (a comma
-separated list
). If the
748 second argument is present and nonempty
, it is a sequence of digits
749 and
/or letters which indicates the subexpression to test
, using the
750 same syntax as genextract
/genrecog
's location strings: 0-9 for
751 XEXP (op, n), a-z for XVECEXP (op, 0, n); each character applies to
752 the result of the one before it. */
753 DEF_RTL_EXPR(MATCH_CODE, "match_code", "ss", RTX_MATCH)
755 /* Appears only in define_predicate/define_special_predicate
756 expressions. The argument is a C expression to be injected at this
757 point in the predicate formula. */
758 DEF_RTL_EXPR(MATCH_TEST, "match_test", "s", RTX_MATCH)
760 /* Insn (and related) definitions. */
762 /* Definition of the pattern for one kind of instruction.
764 0: names this instruction.
765 If the name is the null string, the instruction is in the
766 machine description just to be recognized, and will never be emitted by
767 the tree to rtl expander.
769 2: is a string which is a C expression
770 giving an additional condition for recognizing this pattern.
771 A null string means no extra condition.
772 3: is the action to execute if this pattern is matched.
773 If this assembler code template starts with a * then it is a fragment of
774 C code to run to decide on a template to use. Otherwise, it is the
776 4: optionally, a vector of attributes for this insn.
778 DEF_RTL_EXPR(DEFINE_INSN, "define_insn", "sEsTV", RTX_EXTRA)
780 /* Definition of a peephole optimization.
781 1st operand: vector of insn patterns to match
782 2nd operand: C expression that must be true
783 3rd operand: template or C code to produce assembler output.
784 4: optionally, a vector of attributes for this insn.
786 This form is deprecated; use define_peephole2 instead. */
787 DEF_RTL_EXPR(DEFINE_PEEPHOLE, "define_peephole", "EsTV", RTX_EXTRA)
789 /* Definition of a split operation.
790 1st operand: insn pattern to match
791 2nd operand: C expression that must be true
792 3rd operand: vector of insn patterns to place into a SEQUENCE
793 4th operand: optionally, some C code to execute before generating the
794 insns. This might, for example, create some RTX's and store them in
795 elements of `recog_data.operand
' for use by the vector of
797 (`operands' is an alias here for `recog_data.operand
'). */
798 DEF_RTL_EXPR(DEFINE_SPLIT, "define_split", "EsES", RTX_EXTRA)
800 /* Definition of an insn and associated split.
801 This is the concatenation, with a few modifications, of a define_insn
802 and a define_split which share the same pattern.
804 0: names this instruction.
805 If the name is the null string, the instruction is in the
806 machine description just to be recognized, and will never be emitted by
807 the tree to rtl expander.
809 2: is a string which is a C expression
810 giving an additional condition for recognizing this pattern.
811 A null string means no extra condition.
812 3: is the action to execute if this pattern is matched.
813 If this assembler code template starts with a * then it is a fragment of
814 C code to run to decide on a template to use. Otherwise, it is the
816 4: C expression that must be true for split. This may start with "&&"
817 in which case the split condition is the logical and of the insn
818 condition and what follows the "&&" of this operand.
819 5: vector of insn patterns to place into a SEQUENCE
820 6: optionally, some C code to execute before generating the
821 insns. This might, for example, create some RTX's and store them in
822 elements of `recog_data.operand
' for use by the vector of
824 (`operands' is an alias here for `recog_data.operand
').
825 7: optionally, a vector of attributes for this insn. */
826 DEF_RTL_EXPR(DEFINE_INSN_AND_SPLIT, "define_insn_and_split", "sEsTsESV", RTX_EXTRA)
828 /* Definition of an RTL peephole operation.
829 Follows the same arguments as define_split. */
830 DEF_RTL_EXPR(DEFINE_PEEPHOLE2, "define_peephole2", "EsES", RTX_EXTRA)
832 /* Define how to generate multiple insns for a standard insn name.
833 1st operand: the insn name.
834 2nd operand: vector of insn-patterns.
835 Use match_operand to substitute an element of `recog_data.operand'.
836 3rd operand
: C expression that must be true for this to be available.
837 This may not test any operands.
838 4th operand
: Extra C code to execute before generating the insns.
839 This might
, for example
, create some RTX
's and store them in
840 elements of `recog_data.operand' for use by the vector of
842 (`operands
' is an alias here for `recog_data.operand').
*/
843 DEF_RTL_EXPR(DEFINE_EXPAND
, "define_expand", "sEss", RTX_EXTRA
)
845 /* Define a requirement for delay slots.
846 1st operand
: Condition involving insn attributes that
, if true
,
847 indicates that the insn requires the number of delay slots
849 2nd operand
: Vector whose length is the three times the number of delay
851 Each entry gives three conditions
, each involving attributes.
852 The first must be true for an insn to occupy that delay slot
853 location. The second is true for all insns that can be
854 annulled if the branch is true and the third is true for all
855 insns that can be annulled if the branch is false.
857 Multiple DEFINE_DELAYs may be present. They indicate differing
858 requirements for delay slots.
*/
859 DEF_RTL_EXPR(DEFINE_DELAY
, "define_delay", "eE", RTX_EXTRA
)
861 /* Define attribute computation for `asm
' instructions. */
862 DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES, "define_asm_attributes", "V", RTX_EXTRA)
864 /* Definition of a conditional execution meta operation. Automatically
865 generates new instances of DEFINE_INSN, selected by having attribute
866 "predicable" true. The new pattern will contain a COND_EXEC and the
867 predicate at top-level.
870 0: The predicate pattern. The top-level form should match a
871 relational operator. Operands should have only one alternative.
872 1: A C expression giving an additional condition for recognizing
873 the generated pattern.
874 2: A template or C code to produce assembler output. */
875 DEF_RTL_EXPR(DEFINE_COND_EXEC, "define_cond_exec", "Ess", RTX_EXTRA)
877 /* Definition of an operand predicate. The difference between
878 DEFINE_PREDICATE and DEFINE_SPECIAL_PREDICATE is that genrecog will
879 not warn about a match_operand with no mode if it has a predicate
880 defined with DEFINE_SPECIAL_PREDICATE.
883 0: The name of the predicate.
884 1: A boolean expression which computes whether or not the predicate
885 matches. This expression can use IOR, AND, NOT, MATCH_OPERAND,
886 MATCH_CODE, and MATCH_TEST. It must be specific enough that genrecog
887 can calculate the set of RTX codes that can possibly match.
888 2: A C function body which must return true for the predicate to match.
889 Optional. Use this when the test is too complicated to fit into a
890 match_test expression. */
891 DEF_RTL_EXPR(DEFINE_PREDICATE, "define_predicate", "ses", RTX_EXTRA)
892 DEF_RTL_EXPR(DEFINE_SPECIAL_PREDICATE, "define_special_predicate", "ses", RTX_EXTRA)
894 /* Definition of a register operand constraint. This simply maps the
895 constraint string to a register class.
898 0: The name of the constraint (often, but not always, a single letter).
899 1: A C expression which evaluates to the appropriate register class for
900 this constraint. If this is not just a constant, it should look only
901 at -m switches and the like.
902 2: A docstring for this constraint, in Texinfo syntax; not currently
903 used, in future will be incorporated into the manual's list of
904 machine
-specific operand constraints.
*/
905 DEF_RTL_EXPR(DEFINE_REGISTER_CONSTRAINT
, "define_register_constraint", "sss", RTX_EXTRA
)
907 /* Definition of a non
-register operand constraint. These look at the
908 operand and decide whether it fits the constraint.
910 DEFINE_CONSTRAINT gets no special treatment if it fails to match.
911 It is appropriate for constant
-only constraints
, and most others.
913 DEFINE_MEMORY_CONSTRAINT tells reload that this constraint can be made
914 to match
, if it doesn
't already, by converting the operand to the form
915 (mem (reg X)) where X is a base register. It is suitable for constraints
916 that describe a subset of all memory references.
918 DEFINE_ADDRESS_CONSTRAINT tells reload that this constraint can be made
919 to match, if it doesn't already
, by converting the operand to the form
920 (reg X
) where X is a base register. It is suitable for constraints that
921 describe a subset of all address references.
923 When in doubt
, use plain DEFINE_CONSTRAINT.
926 0: The name of the
constraint (often
, but not always
, a single letter
).
927 1: A docstring for this constraint
, in Texinfo syntax
; not currently
928 used
, in future will be incorporated into the manual
's list of
929 machine-specific operand constraints.
930 2: A boolean expression which computes whether or not the constraint
931 matches. It should follow the same rules as a define_predicate
932 expression, including the bit about specifying the set of RTX codes
933 that could possibly match. MATCH_TEST subexpressions may make use of
935 `op' - the RTL object defining the operand.
936 `mode
' - the mode of `op'.
937 `ival
' - INTVAL(op), if op is a CONST_INT.
938 `hval' - CONST_DOUBLE_HIGH(op
), if op is an integer CONST_DOUBLE.
939 `lval
' - CONST_DOUBLE_LOW(op), if op is an integer CONST_DOUBLE.
940 `rval' - CONST_DOUBLE_REAL_VALUE(op
), if op is a floating
-point
942 Do not use ival
/hval
/lval
/rval if op is not the appropriate kind of
944 DEF_RTL_EXPR(DEFINE_CONSTRAINT
, "define_constraint", "sse", RTX_EXTRA
)
945 DEF_RTL_EXPR(DEFINE_MEMORY_CONSTRAINT
, "define_memory_constraint", "sse", RTX_EXTRA
)
946 DEF_RTL_EXPR(DEFINE_ADDRESS_CONSTRAINT
, "define_address_constraint", "sse", RTX_EXTRA
)
949 /* Constructions for CPU pipeline description described by NDFAs.
*/
951 /* (define_cpu_unit string
[string
]) describes cpu functional
952 units (separated by comma
).
954 1st operand
: Names of cpu functional units.
955 2nd operand
: Name of
automaton (see comments for DEFINE_AUTOMATON
).
957 All define_reservations
, define_cpu_units
, and
958 define_query_cpu_units should have unique names which may not be
960 DEF_RTL_EXPR(DEFINE_CPU_UNIT
, "define_cpu_unit", "sS", RTX_EXTRA
)
962 /* (define_query_cpu_unit string
[string
]) describes cpu functional
963 units analogously to define_cpu_unit. The reservation of such
964 units can be queried for automaton state.
*/
965 DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT
, "define_query_cpu_unit", "sS", RTX_EXTRA
)
967 /* (exclusion_set string string
) means that each CPU functional unit
968 in the first string can not be reserved simultaneously with any
969 unit whose name is in the second string and vise versa. CPU units
970 in the string are separated by commas. For example
, it is useful
971 for description CPU with fully pipelined floating point functional
972 unit which can execute simultaneously only single floating point
973 insns or only double floating point insns. All CPU functional
974 units in a set should belong to the same automaton.
*/
975 DEF_RTL_EXPR(EXCLUSION_SET
, "exclusion_set", "ss", RTX_EXTRA
)
977 /* (presence_set string string
) means that each CPU functional unit in
978 the first string can not be reserved unless at least one of pattern
979 of units whose names are in the second string is reserved. This is
980 an asymmetric relation. CPU units or unit patterns in the strings
981 are separated by commas. Pattern is one unit name or unit names
982 separated by white
-spaces.
984 For example
, it is useful for description that slot1 is reserved
985 after slot0 reservation for a VLIW processor. We could describe it
986 by the following construction
988 (presence_set
"slot1" "slot0")
990 Or slot1 is reserved only after slot0 and unit b0 reservation. In
991 this case we could write
993 (presence_set
"slot1" "slot0 b0")
995 All CPU functional units in a set should belong to the same
997 DEF_RTL_EXPR(PRESENCE_SET
, "presence_set", "ss", RTX_EXTRA
)
999 /* (final_presence_set string string
) is analogous to `presence_set
'.
1000 The difference between them is when checking is done. When an
1001 instruction is issued in given automaton state reflecting all
1002 current and planned unit reservations, the automaton state is
1003 changed. The first state is a source state, the second one is a
1004 result state. Checking for `presence_set' is done on the source
1005 state reservation
, checking for `final_presence_set
' is done on the
1006 result reservation. This construction is useful to describe a
1007 reservation which is actually two subsequent reservations. For
1010 (presence_set "slot1" "slot0")
1012 the following insn will be never issued (because slot1 requires
1013 slot0 which is absent in the source state).
1015 (define_reservation "insn_and_nop" "slot0 + slot1")
1017 but it can be issued if we use analogous `final_presence_set'.
*/
1018 DEF_RTL_EXPR(FINAL_PRESENCE_SET
, "final_presence_set", "ss", RTX_EXTRA
)
1020 /* (absence_set string string
) means that each CPU functional unit in
1021 the first string can be reserved only if each pattern of units
1022 whose names are in the second string is not reserved. This is an
1023 asymmetric
relation (actually exclusion set is analogous to this
1024 one but it is symmetric
). CPU units or unit patterns in the string
1025 are separated by commas. Pattern is one unit name or unit names
1026 separated by white
-spaces.
1028 For example
, it is useful for description that slot0 can not be
1029 reserved after slot1 or slot2 reservation for a VLIW processor. We
1030 could describe it by the following construction
1032 (absence_set
"slot2" "slot0, slot1")
1034 Or slot2 can not be reserved if slot0 and unit b0 are reserved or
1035 slot1 and unit b1 are reserved . In this case we could write
1037 (absence_set
"slot2" "slot0 b0, slot1 b1")
1039 All CPU functional units in a set should to belong the same
1041 DEF_RTL_EXPR(ABSENCE_SET
, "absence_set", "ss", RTX_EXTRA
)
1043 /* (final_absence_set string string
) is analogous to `absence_set
' but
1044 checking is done on the result (state) reservation. See comments
1045 for `final_presence_set'.
*/
1046 DEF_RTL_EXPR(FINAL_ABSENCE_SET
, "final_absence_set", "ss", RTX_EXTRA
)
1048 /* (define_bypass number out_insn_names in_insn_names
) names bypass
1049 with given
latency (the first number
) from insns given by the first
1050 string (see define_insn_reservation
) into insns given by the second
1051 string. Insn names in the strings are separated by commas. The
1052 third operand is optional name of function which is additional
1053 guard for the bypass. The function will get the two insns as
1054 parameters. If the function returns zero the bypass will be
1055 ignored for this case. Additional guard is necessary to recognize
1056 complicated bypasses
, e.g. when consumer is load address.
*/
1057 DEF_RTL_EXPR(DEFINE_BYPASS
, "define_bypass", "issS", RTX_EXTRA
)
1059 /* (define_automaton string
) describes names of automata generated and
1060 used for pipeline hazards recognition. The names are separated by
1061 comma. Actually it is possibly to generate the single automaton
1062 but unfortunately it can be very large. If we use more one
1063 automata
, the summary size of the automata usually is less than the
1064 single one. The automaton name is used in define_cpu_unit and
1065 define_query_cpu_unit. All automata should have unique names.
*/
1066 DEF_RTL_EXPR(DEFINE_AUTOMATON
, "define_automaton", "s", RTX_EXTRA
)
1068 /* (automata_option string
) describes option for generation of
1069 automata. Currently there are the following options
:
1071 o
"no-minimization" which makes no minimization of automata. This
1072 is only worth to do when we are debugging the description and
1073 need to look more accurately at reservations of states.
1075 o
"time" which means printing additional time statistics about
1076 generation of automata.
1078 o
"v" which means generation of file describing the result
1079 automata. The file has suffix `.dfa
' and can be used for the
1080 description verification and debugging.
1082 o "w" which means generation of warning instead of error for
1083 non-critical errors.
1085 o "ndfa" which makes nondeterministic finite state automata.
1087 o "progress" which means output of a progress bar showing how many
1088 states were generated so far for automaton being processed. */
1089 DEF_RTL_EXPR(AUTOMATA_OPTION, "automata_option", "s", RTX_EXTRA)
1091 /* (define_reservation string string) names reservation (the first
1092 string) of cpu functional units (the 2nd string). Sometimes unit
1093 reservations for different insns contain common parts. In such
1094 case, you can describe common part and use its name (the 1st
1095 parameter) in regular expression in define_insn_reservation. All
1096 define_reservations, define_cpu_units, and define_query_cpu_units
1097 should have unique names which may not be "nothing". */
1098 DEF_RTL_EXPR(DEFINE_RESERVATION, "define_reservation", "ss", RTX_EXTRA)
1100 /* (define_insn_reservation name default_latency condition regexpr)
1101 describes reservation of cpu functional units (the 3nd operand) for
1102 instruction which is selected by the condition (the 2nd parameter).
1103 The first parameter is used for output of debugging information.
1104 The reservations are described by a regular expression according
1105 the following syntax:
1107 regexp = regexp "," oneof
1110 oneof = oneof "|" allof
1113 allof = allof "+" repeat
1116 repeat = element "*" number
1119 element = cpu_function_unit_name
1125 1. "," is used for describing start of the next cycle in
1128 2. "|" is used for describing the reservation described by the
1129 first regular expression *or* the reservation described by the
1130 second regular expression *or* etc.
1132 3. "+" is used for describing the reservation described by the
1133 first regular expression *and* the reservation described by the
1134 second regular expression *and* etc.
1136 4. "*" is used for convenience and simply means sequence in
1137 which the regular expression are repeated NUMBER times with
1138 cycle advancing (see ",").
1140 5. cpu functional unit name which means its reservation.
1142 6. reservation name -- see define_reservation.
1144 7. string "nothing" means no units reservation. */
1146 DEF_RTL_EXPR(DEFINE_INSN_RESERVATION, "define_insn_reservation", "sies", RTX_EXTRA)
1148 /* Expressions used for insn attributes. */
1150 /* Definition of an insn attribute.
1151 1st operand: name of the attribute
1152 2nd operand: comma-separated list of possible attribute values
1153 3rd operand: expression for the default value of the attribute. */
1154 DEF_RTL_EXPR(DEFINE_ATTR, "define_attr", "sse", RTX_EXTRA)
1156 /* Marker for the name of an attribute. */
1157 DEF_RTL_EXPR(ATTR, "attr", "s", RTX_EXTRA)
1159 /* For use in the last (optional) operand of DEFINE_INSN or DEFINE_PEEPHOLE and
1160 in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that
1163 (set_attr "name" "value") is equivalent to
1164 (set (attr "name") (const_string "value")) */
1165 DEF_RTL_EXPR(SET_ATTR, "set_attr", "ss", RTX_EXTRA)
1167 /* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE, this can be used to
1168 specify that attribute values are to be assigned according to the
1169 alternative matched.
1171 The following three expressions are equivalent:
1173 (set (attr "att") (cond [(eq_attrq "alternative" "1") (const_string "a1")
1174 (eq_attrq "alternative" "2") (const_string "a2")]
1175 (const_string "a3")))
1176 (set_attr_alternative "att" [(const_string "a1") (const_string "a2")
1177 (const_string "a3")])
1178 (set_attr "att" "a1,a2,a3")
1180 DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE, "set_attr_alternative", "sE", RTX_EXTRA)
1182 /* A conditional expression true if the value of the specified attribute of
1183 the current insn equals the specified value. The first operand is the
1184 attribute name and the second is the comparison value. */
1185 DEF_RTL_EXPR(EQ_ATTR, "eq_attr", "ss", RTX_EXTRA)
1187 /* A special case of the above representing a set of alternatives. The first
1188 operand is bitmap of the set, the second one is the default value. */
1189 DEF_RTL_EXPR(EQ_ATTR_ALT, "eq_attr_alt", "ii", RTX_EXTRA)
1191 /* A conditional expression which is true if the specified flag is
1192 true for the insn being scheduled in reorg.
1194 genattr.c defines the following flags which can be tested by
1195 (attr_flag "foo") expressions in eligible_for_delay.
1197 forward, backward, very_likely, likely, very_unlikely, and unlikely. */
1199 DEF_RTL_EXPR (ATTR_FLAG, "attr_flag", "s", RTX_EXTRA)
1201 /* General conditional. The first operand is a vector composed of pairs of
1202 expressions. The first element of each pair is evaluated, in turn.
1203 The value of the conditional is the second expression of the first pair
1204 whose first expression evaluates nonzero. If none of the expressions is
1205 true, the second operand will be used as the value of the conditional. */
1206 DEF_RTL_EXPR(COND, "cond", "Ee", RTX_EXTRA)
1208 #endif /* GENERATOR_FILE */