1 /* This file contains the definitions and documentation for the
2 Register Transfer
Expressions (rtx
's) that make up the
3 Register Transfer Language (rtl) used in the Back End of the GNU compiler.
4 Copyright (C) 1987, 1988, 1992, 1994, 1995, 1997, 1998, 1999, 2000, 2004,
5 2005, 2006, 2007, 2008, 2009, 2010
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 3, 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 COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
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->u.fld[] (field) in this rtx.
43 These formats are stored in rtx_format[].
44 The meaning of the formats is documented in front of this array in rtl.c
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:
50 an rtx code that can be used to represent a constant object
53 an rtx code that can be used to represent an object (e.g, REG, MEM)
55 an rtx code for a comparison (e.g, LT, GT)
57 an rtx code for a commutative comparison (e.g, EQ, NE, ORDERED)
59 an rtx code for a unary arithmetic expression (e.g, NEG, NOT)
61 an rtx code for a commutative binary operation (e.g,, PLUS, MULT)
63 an rtx code for a non-bitfield three input operation (IF_THEN_ELSE)
65 an rtx code for a non-commutative binary operation (e.g., MINUS, DIV)
67 an rtx code for a bit-field operation (ZERO_EXTRACT, SIGN_EXTRACT)
69 an rtx code for a machine insn (INSN, JUMP_INSN, CALL_INSN)
71 an rtx code for something that matches in insns (e.g, MATCH_DUP)
73 an rtx code for autoincrement addressing modes (e.g. POST_DEC)
77 All of the expressions that appear only in machine descriptions,
78 not in RTL used by the compiler itself, are at the end of the file. */
80 /* Unknown, or no such operation; the enumeration constant should have
82 DEF_RTL_EXPR(UNKNOWN, "UnKnown", "*", RTX_EXTRA)
84 /* Used in the cselib routines to describe a value. Objects of this
85 kind are only allocated in cselib.c, in an alloc pool instead of in
86 GC memory. The only operand of a VALUE is a cselib_val_struct.
87 var-tracking requires this to have a distinct integral value from
88 DECL codes in trees. */
89 DEF_RTL_EXPR(VALUE, "value", "0", RTX_OBJ)
91 /* The RTL generated for a DEBUG_EXPR_DECL. It links back to the
92 DEBUG_EXPR_DECL in the first operand. */
93 DEF_RTL_EXPR(DEBUG_EXPR, "debug_expr", "0", RTX_OBJ)
95 /* ---------------------------------------------------------------------
96 Expressions used in constructing lists.
97 --------------------------------------------------------------------- */
99 /* a linked list of expressions */
100 DEF_RTL_EXPR(EXPR_LIST, "expr_list", "ee", RTX_EXTRA)
102 /* a linked list of instructions.
103 The insns are represented in print by their uids. */
104 DEF_RTL_EXPR(INSN_LIST, "insn_list", "ue", RTX_EXTRA)
106 /* SEQUENCE appears in the result of a `gen_...' function
107 for a DEFINE_EXPAND that wants to make several insns.
108 Its elements are the bodies of the insns that should be made.
109 `emit_insn
' takes the SEQUENCE apart and makes separate insns. */
110 DEF_RTL_EXPR(SEQUENCE, "sequence", "E", RTX_EXTRA)
112 /* Refers to the address of its argument. This is only used in alias.c. */
113 DEF_RTL_EXPR(ADDRESS, "address", "e", RTX_MATCH)
115 /* ----------------------------------------------------------------------
116 Expression types used for things in the instruction chain.
118 All formats must start with "iuu" to handle the chain.
119 Each insn expression holds an rtl instruction and its semantics
120 during back-end processing.
121 See macros's in
"rtl.h" for the meaning of each rtx
->u.fld
[].
123 ---------------------------------------------------------------------- */
125 /* An annotation for variable assignment tracking.
*/
126 DEF_RTL_EXPR(DEBUG_INSN
, "debug_insn", "iuuBeiie", RTX_INSN
)
128 /* An instruction that cannot jump.
*/
129 DEF_RTL_EXPR(INSN
, "insn", "iuuBeiie", RTX_INSN
)
131 /* An instruction that can possibly jump.
132 Fields ( rtx
->u.fld
[] ) have exact same meaning as INSN
's. */
133 DEF_RTL_EXPR(JUMP_INSN, "jump_insn", "iuuBeiie0", RTX_INSN)
135 /* An instruction that can possibly call a subroutine
136 but which will not change which instruction comes next
137 in the current function.
138 Field ( rtx->u.fld[8] ) is CALL_INSN_FUNCTION_USAGE.
139 All other fields ( rtx->u.fld[] ) have exact same meaning as INSN's.
*/
140 DEF_RTL_EXPR(CALL_INSN
, "call_insn", "iuuBeiiee", RTX_INSN
)
142 /* A marker that indicates that control will not flow through.
*/
143 DEF_RTL_EXPR(BARRIER
, "barrier", "iuu00000", RTX_EXTRA
)
145 /* Holds a label that is followed by instructions.
147 4: is used in jump.c for the use
-count of the label.
148 5: is used in the sh backend.
149 6: is a number that is unique in the entire compilation.
150 7: is the user
-given name of the label
, if any.
*/
151 DEF_RTL_EXPR(CODE_LABEL
, "code_label", "iuuB00is", RTX_EXTRA
)
153 /* Say where in the code a source line starts
, for symbol table
's sake.
155 4: note-specific data
157 6: unique number if insn_note == note_insn_deleted_label. */
158 DEF_RTL_EXPR(NOTE, "note", "iuuB0ni", RTX_EXTRA)
160 /* ----------------------------------------------------------------------
161 Top level constituents of INSN, JUMP_INSN and CALL_INSN.
162 ---------------------------------------------------------------------- */
164 /* Conditionally execute code.
165 Operand 0 is the condition that if true, the code is executed.
166 Operand 1 is the code to be executed (typically a SET).
168 Semantics are that there are no side effects if the condition
169 is false. This pattern is created automatically by the if_convert
170 pass run after reload or by target-specific splitters. */
171 DEF_RTL_EXPR(COND_EXEC, "cond_exec", "ee", RTX_EXTRA)
173 /* Several operations to be done in parallel (perhaps under COND_EXEC). */
174 DEF_RTL_EXPR(PARALLEL, "parallel", "E", RTX_EXTRA)
176 /* A string that is passed through to the assembler as input.
177 One can obviously pass comments through by using the
178 assembler comment syntax.
179 These occur in an insn all by themselves as the PATTERN.
180 They also appear inside an ASM_OPERANDS
181 as a convenient way to hold a string. */
182 DEF_RTL_EXPR(ASM_INPUT, "asm_input", "si", RTX_EXTRA)
184 /* An assembler instruction with operands.
185 1st operand is the instruction template.
186 2nd operand is the constraint for the output.
187 3rd operand is the number of the output this expression refers to.
188 When an insn stores more than one value, a separate ASM_OPERANDS
189 is made for each output; this integer distinguishes them.
190 4th is a vector of values of input operands.
191 5th is a vector of modes and constraints for the input operands.
192 Each element is an ASM_INPUT containing a constraint string
193 and whose mode indicates the mode of the input operand.
194 6th is a vector of labels that may be branched to by the asm.
195 7th is the source line number. */
196 DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEEi", RTX_EXTRA)
198 /* A machine-specific operation.
199 1st operand is a vector of operands being used by the operation so that
200 any needed reloads can be done.
201 2nd operand is a unique value saying which of a number of machine-specific
202 operations is to be performed.
203 (Note that the vector must be the first operand because of the way that
204 genrecog.c record positions within an insn.)
206 UNSPEC can occur all by itself in a PATTERN, as a component of a PARALLEL,
207 or inside an expression.
208 UNSPEC by itself or as a component of a PARALLEL
209 is currently considered not deletable.
211 FIXME: Replace all uses of UNSPEC that appears by itself or as a component
212 of a PARALLEL with USE.
214 DEF_RTL_EXPR(UNSPEC, "unspec", "Ei", RTX_EXTRA)
216 /* Similar, but a volatile operation and one which may trap. */
217 DEF_RTL_EXPR(UNSPEC_VOLATILE, "unspec_volatile", "Ei", RTX_EXTRA)
219 /* Vector of addresses, stored as full words. */
220 /* Each element is a LABEL_REF to a CODE_LABEL whose address we want. */
221 DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", RTX_EXTRA)
223 /* Vector of address differences X0 - BASE, X1 - BASE, ...
224 First operand is BASE; the vector contains the X's.
225 The machine mode of this rtx says how much space to leave
226 for each difference and is adjusted by branch shortening if
227 CASE_VECTOR_SHORTEN_MODE is defined.
228 The third and fourth operands store the target labels with the
229 minimum and maximum addresses respectively.
230 The fifth operand stores flags for use by branch shortening.
231 Set at the start of shorten_branches
:
232 min_align
: the minimum alignment for any of the target labels.
233 base_after_vec
: true iff BASE is after the ADDR_DIFF_VEC.
234 min_after_vec
: true iff minimum addr target label is after the ADDR_DIFF_VEC.
235 max_after_vec
: true iff maximum addr target label is after the ADDR_DIFF_VEC.
236 min_after_base
: true iff minimum address target label is after BASE.
237 max_after_base
: true iff maximum address target label is after BASE.
238 Set by the actual branch shortening process
:
239 offset_unsigned
: true iff offsets have to be treated as unsigned.
240 scale
: scaling that is necessary to make offsets fit into the mode.
242 The third
, fourth and fifth operands are only valid when
243 CASE_VECTOR_SHORTEN_MODE is defined
, and only in an optimizing
246 DEF_RTL_EXPR(ADDR_DIFF_VEC
, "addr_diff_vec", "eEee0", RTX_EXTRA
)
248 /* Memory prefetch
, with attributes supported on some targets.
249 Operand
1 is the address of the memory to fetch.
250 Operand
2 is
1 for a write access
, 0 otherwise.
251 Operand
3 is the level of temporal locality
; 0 means there is no
252 temporal locality and
1, 2, and
3 are for increasing levels of temporal
255 The attributes specified by operands
2 and
3 are ignored for targets
256 whose prefetch instructions do not support them.
*/
257 DEF_RTL_EXPR(PREFETCH
, "prefetch", "eee", RTX_EXTRA
)
259 /* ----------------------------------------------------------------------
260 At the top level of an
instruction (perhaps under PARALLEL
).
261 ---------------------------------------------------------------------- */
264 Operand
1 is the
location (REG
, MEM
, PC
, CC0 or whatever
) assigned to.
265 Operand
2 is the value stored there.
266 ALL assignment must use
SET.
267 Instructions that do multiple assignments must use multiple
SET,
269 DEF_RTL_EXPR(SET, "set", "ee", RTX_EXTRA
)
271 /* Indicate something is used in a way that we don
't want to explain.
272 For example, subroutine calls will use the register
273 in which the static chain is passed.
275 USE can not appear as an operand of other rtx except for PARALLEL.
276 USE is not deletable, as it indicates that the operand
277 is used in some unknown way. */
278 DEF_RTL_EXPR(USE, "use", "e", RTX_EXTRA)
280 /* Indicate something is clobbered in a way that we don't want to explain.
281 For example
, subroutine calls will clobber some physical registers
282 (the ones that are by convention not saved
).
284 CLOBBER can not appear as an operand of other rtx except for PARALLEL.
285 CLOBBER of a hard register appearing by
itself (not within PARALLEL
)
286 is considered undeletable before reload.
*/
287 DEF_RTL_EXPR(CLOBBER
, "clobber", "e", RTX_EXTRA
)
289 /* Call a subroutine.
290 Operand
1 is the address to call.
291 Operand
2 is the number of arguments.
*/
293 DEF_RTL_EXPR(CALL
, "call", "ee", RTX_EXTRA
)
295 /* Return from a subroutine.
*/
297 DEF_RTL_EXPR(RETURN, "return", "", RTX_EXTRA
)
299 /* Special for EH return from subroutine.
*/
301 DEF_RTL_EXPR(EH_RETURN
, "eh_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 /* ----------------------------------------------------------------------
310 Primitive values for use in expressions.
311 ---------------------------------------------------------------------- */
313 /* numeric integer constant
*/
314 DEF_RTL_EXPR(CONST_INT
, "const_int", "w", RTX_CONST_OBJ
)
316 /* fixed
-point constant
*/
317 DEF_RTL_EXPR(CONST_FIXED
, "const_fixed", "www", RTX_CONST_OBJ
)
319 /* numeric floating point constant.
320 Operands hold the value. They are all
'w' and there may be from
2 to
6;
322 DEF_RTL_EXPR(CONST_DOUBLE
, "const_double", CONST_DOUBLE_FORMAT
, RTX_CONST_OBJ
)
324 /* Describes a vector constant.
*/
325 DEF_RTL_EXPR(CONST_VECTOR
, "const_vector", "E", RTX_CONST_OBJ
)
327 /* String constant. Used for attributes in machine descriptions and
328 for special cases in DWARF2 debug output.
NOT used for source
-
329 language string constants.
*/
330 DEF_RTL_EXPR(CONST_STRING
, "const_string", "s", RTX_OBJ
)
332 /* This is used to encapsulate an expression whose value is constant
333 (such as the sum of a SYMBOL_REF and a CONST_INT
) so that it will be
334 recognized as a constant operand rather than by arithmetic instructions.
*/
336 DEF_RTL_EXPR(CONST, "const", "e", RTX_CONST_OBJ
)
338 /* program counter. Ordinary jumps are represented
339 by a
SET whose first operand
is (PC
).
*/
340 DEF_RTL_EXPR(PC
, "pc", "", RTX_OBJ
)
342 /* A register. The
"operand" is the register number
, accessed with
343 the REGNO macro. If this number is less than FIRST_PSEUDO_REGISTER
344 than a hardware register is being referred to. The second operand
345 holds the original register number
- this will be different for a
346 pseudo register that got turned into a hard register. The third
347 operand points to a reg_attrs structure.
348 This rtx needs to have as
many (or more
) fields as a MEM
, since we
349 can change REG rtx
's into MEMs during reload. */
350 DEF_RTL_EXPR(REG, "reg", "i00", RTX_OBJ)
352 /* A scratch register. This represents a register used only within a
353 single insn. It will be turned into a REG during register allocation
354 or reload unless the constraint indicates that the register won't be
355 needed
, in which case it can remain a SCRATCH. This code is
356 marked as having one operand so it can be turned into a REG.
*/
357 DEF_RTL_EXPR(SCRATCH
, "scratch", "0", RTX_OBJ
)
359 /* A reference to a part of another value. The first operand is the
360 complete value and the second is the byte offset of the selected part.
*/
361 DEF_RTL_EXPR(SUBREG
, "subreg", "ei", RTX_EXTRA
)
363 /* This one
-argument rtx is used for move instructions
364 that are guaranteed to alter only the low part of a destination.
365 Thus
, (SET (SUBREG
:HI (REG...
)) (MEM
:HI ...
))
366 has an unspecified effect on the high part of REG
,
367 but (SET (STRICT_LOW_PART (SUBREG
:HI (REG...
))) (MEM
:HI ...
))
368 is guaranteed to alter only the bits of REG that are in HImode.
370 The actual instruction used is probably the same in both cases
,
371 but the register constraints may be tighter when STRICT_LOW_PART
374 DEF_RTL_EXPR(STRICT_LOW_PART
, "strict_low_part", "e", RTX_EXTRA
)
376 /* (CONCAT a b
) represents the virtual concatenation of a and b
377 to make a value that has as many bits as a and b put together.
378 This is used for complex values. Normally it appears only
379 in DECL_RTLs and during RTL generation
, but not in the insn chain.
*/
380 DEF_RTL_EXPR(CONCAT
, "concat", "ee", RTX_OBJ
)
382 /* (CONCATN
[a1 a2 ... an
]) represents the virtual concatenation of
383 all An to make a value. This is an extension of CONCAT to larger
384 number of components. Like CONCAT
, it should not appear in the
385 insn chain. Every element of the CONCATN is the same size.
*/
386 DEF_RTL_EXPR(CONCATN
, "concatn", "E", RTX_OBJ
)
388 /* A memory location
; operand is the address. The second operand is the
389 alias set to which this MEM belongs. We use `
0' instead of `w' for this
390 field so that the field need not be specified in machine descriptions.
*/
391 DEF_RTL_EXPR(MEM
, "mem", "e0", RTX_OBJ
)
393 /* Reference to an assembler label in the code for this function.
394 The operand is a CODE_LABEL found in the insn chain.
*/
395 DEF_RTL_EXPR(LABEL_REF
, "label_ref", "u", RTX_CONST_OBJ
)
397 /* Reference to a named label
:
398 Operand
0: label name
399 Operand
1: flags (see SYMBOL_FLAG_
* in rtl.h
)
400 Operand
2: tree from which this symbol is derived
, or null.
401 This is either a DECL node
, or some kind of constant.
*/
402 DEF_RTL_EXPR(SYMBOL_REF
, "symbol_ref", "s00", RTX_CONST_OBJ
)
404 /* The condition code register is represented
, in our imagination
,
405 as a register holding a value that can be compared to zero.
406 In fact
, the machine has already compared them and recorded the
407 results
; but instructions that look at the condition code
408 pretend to be looking at the entire value and comparing it.
*/
409 DEF_RTL_EXPR(CC0
, "cc0", "", RTX_OBJ
)
411 /* ----------------------------------------------------------------------
412 Expressions for operators in an rtl pattern
413 ---------------------------------------------------------------------- */
415 /* if_then_else. This is used in representing ordinary
416 conditional jump instructions.
421 DEF_RTL_EXPR(IF_THEN_ELSE
, "if_then_else", "eee", RTX_TERNARY
)
423 /* Comparison
, produces a condition code result.
*/
424 DEF_RTL_EXPR(COMPARE
, "compare", "ee", RTX_BIN_ARITH
)
427 DEF_RTL_EXPR(PLUS
, "plus", "ee", RTX_COMM_ARITH
)
429 /* Operand
0 minus operand
1.
*/
430 DEF_RTL_EXPR(MINUS
, "minus", "ee", RTX_BIN_ARITH
)
432 /* Minus operand
0.
*/
433 DEF_RTL_EXPR(NEG
, "neg", "e", RTX_UNARY
)
435 DEF_RTL_EXPR(MULT
, "mult", "ee", RTX_COMM_ARITH
)
437 /* Multiplication with signed saturation
*/
438 DEF_RTL_EXPR(SS_MULT
, "ss_mult", "ee", RTX_COMM_ARITH
)
439 /* Multiplication with unsigned saturation
*/
440 DEF_RTL_EXPR(US_MULT
, "us_mult", "ee", RTX_COMM_ARITH
)
442 /* Operand
0 divided by operand
1.
*/
443 DEF_RTL_EXPR(DIV, "div", "ee", RTX_BIN_ARITH
)
444 /* Division with signed saturation
*/
445 DEF_RTL_EXPR(SS_DIV
, "ss_div", "ee", RTX_BIN_ARITH
)
446 /* Division with unsigned saturation
*/
447 DEF_RTL_EXPR(US_DIV
, "us_div", "ee", RTX_BIN_ARITH
)
449 /* Remainder of operand
0 divided by operand
1.
*/
450 DEF_RTL_EXPR(MOD, "mod", "ee", RTX_BIN_ARITH
)
452 /* Unsigned divide and remainder.
*/
453 DEF_RTL_EXPR(UDIV
, "udiv", "ee", RTX_BIN_ARITH
)
454 DEF_RTL_EXPR(UMOD
, "umod", "ee", RTX_BIN_ARITH
)
456 /* Bitwise operations.
*/
457 DEF_RTL_EXPR(AND, "and", "ee", RTX_COMM_ARITH
)
458 DEF_RTL_EXPR(IOR
, "ior", "ee", RTX_COMM_ARITH
)
459 DEF_RTL_EXPR(XOR
, "xor", "ee", RTX_COMM_ARITH
)
460 DEF_RTL_EXPR(NOT, "not", "e", RTX_UNARY
)
463 0: value to be shifted.
464 1: number of bits.
*/
465 DEF_RTL_EXPR(ASHIFT
, "ashift", "ee", RTX_BIN_ARITH
) /* shift left
*/
466 DEF_RTL_EXPR(ROTATE
, "rotate", "ee", RTX_BIN_ARITH
) /* rotate left
*/
467 DEF_RTL_EXPR(ASHIFTRT
, "ashiftrt", "ee", RTX_BIN_ARITH
) /* arithmetic shift right
*/
468 DEF_RTL_EXPR(LSHIFTRT
, "lshiftrt", "ee", RTX_BIN_ARITH
) /* logical shift right
*/
469 DEF_RTL_EXPR(ROTATERT
, "rotatert", "ee", RTX_BIN_ARITH
) /* rotate right
*/
471 /* Minimum and maximum values of two operands. We need both signed and
472 unsigned forms.
(We cannot use
MIN for SMIN because it conflicts
473 with a macro of the same name.
) The signed variants should be used
474 with floating point. Further
, if both operands are zeros
, or if either
475 operand is NaN
, then it is unspecified which of the two operands is
476 returned as the result.
*/
478 DEF_RTL_EXPR(SMIN
, "smin", "ee", RTX_COMM_ARITH
)
479 DEF_RTL_EXPR(SMAX
, "smax", "ee", RTX_COMM_ARITH
)
480 DEF_RTL_EXPR(UMIN
, "umin", "ee", RTX_COMM_ARITH
)
481 DEF_RTL_EXPR(UMAX
, "umax", "ee", RTX_COMM_ARITH
)
483 /* These unary operations are used to represent incrementation
484 and decrementation as they occur in memory addresses.
485 The amount of increment or decrement are not represented
486 because they can be understood from the machine
-mode of the
487 containing MEM. These operations exist in only two cases
:
488 1. pushes onto the stack.
489 2. created automatically by the auto
-inc
-dec pass.
*/
490 DEF_RTL_EXPR(PRE_DEC
, "pre_dec", "e", RTX_AUTOINC
)
491 DEF_RTL_EXPR(PRE_INC
, "pre_inc", "e", RTX_AUTOINC
)
492 DEF_RTL_EXPR(POST_DEC
, "post_dec", "e", RTX_AUTOINC
)
493 DEF_RTL_EXPR(POST_INC
, "post_inc", "e", RTX_AUTOINC
)
495 /* These binary operations are used to represent generic address
496 side
-effects in memory addresses
, except for simple incrementation
497 or decrementation which use the above operations. They are
498 created automatically by the life_analysis pass in flow.c.
499 The first operand is a REG which is used as the address.
500 The second operand is an expression that is assigned to the
501 register
, either
before (PRE_MODIFY
) or
after (POST_MODIFY
)
502 evaluating the address.
503 Currently
, the compiler can only handle second operands of the
504 form (plus (reg
) (reg
)) and (plus (reg
) (const_int
)), where
505 the first operand of the PLUS has to be the same register as
506 the first operand of the
*_MODIFY.
*/
507 DEF_RTL_EXPR(PRE_MODIFY
, "pre_modify", "ee", RTX_AUTOINC
)
508 DEF_RTL_EXPR(POST_MODIFY
, "post_modify", "ee", RTX_AUTOINC
)
510 /* Comparison operations. The ordered comparisons exist in two
511 flavors
, signed and unsigned.
*/
512 DEF_RTL_EXPR(NE
, "ne", "ee", RTX_COMM_COMPARE
)
513 DEF_RTL_EXPR(EQ
, "eq", "ee", RTX_COMM_COMPARE
)
514 DEF_RTL_EXPR(GE
, "ge", "ee", RTX_COMPARE
)
515 DEF_RTL_EXPR(GT
, "gt", "ee", RTX_COMPARE
)
516 DEF_RTL_EXPR(LE
, "le", "ee", RTX_COMPARE
)
517 DEF_RTL_EXPR(LT
, "lt", "ee", RTX_COMPARE
)
518 DEF_RTL_EXPR(GEU
, "geu", "ee", RTX_COMPARE
)
519 DEF_RTL_EXPR(GTU
, "gtu", "ee", RTX_COMPARE
)
520 DEF_RTL_EXPR(LEU
, "leu", "ee", RTX_COMPARE
)
521 DEF_RTL_EXPR(LTU
, "ltu", "ee", RTX_COMPARE
)
523 /* Additional floating point unordered comparison flavors.
*/
524 DEF_RTL_EXPR(UNORDERED
, "unordered", "ee", RTX_COMM_COMPARE
)
525 DEF_RTL_EXPR(ORDERED
, "ordered", "ee", RTX_COMM_COMPARE
)
527 /* These are equivalent to unordered or ...
*/
528 DEF_RTL_EXPR(UNEQ
, "uneq", "ee", RTX_COMM_COMPARE
)
529 DEF_RTL_EXPR(UNGE
, "unge", "ee", RTX_COMPARE
)
530 DEF_RTL_EXPR(UNGT
, "ungt", "ee", RTX_COMPARE
)
531 DEF_RTL_EXPR(UNLE
, "unle", "ee", RTX_COMPARE
)
532 DEF_RTL_EXPR(UNLT
, "unlt", "ee", RTX_COMPARE
)
534 /* This is an ordered NE
, ie
!UNEQ
, ie false for NaN.
*/
535 DEF_RTL_EXPR(LTGT
, "ltgt", "ee", RTX_COMM_COMPARE
)
537 /* Represents the result of sign
-extending the sole operand.
538 The machine modes of the operand and of the SIGN_EXTEND expression
539 determine how much sign
-extension is going on.
*/
540 DEF_RTL_EXPR(SIGN_EXTEND
, "sign_extend", "e", RTX_UNARY
)
542 /* Similar for zero
-extension (such as unsigned short to int
).
*/
543 DEF_RTL_EXPR(ZERO_EXTEND
, "zero_extend", "e", RTX_UNARY
)
545 /* Similar but here the operand has a wider mode.
*/
546 DEF_RTL_EXPR(TRUNCATE
, "truncate", "e", RTX_UNARY
)
548 /* Similar for extending floating
-point
values (such as SFmode to DFmode
).
*/
549 DEF_RTL_EXPR(FLOAT_EXTEND
, "float_extend", "e", RTX_UNARY
)
550 DEF_RTL_EXPR(FLOAT_TRUNCATE
, "float_truncate", "e", RTX_UNARY
)
552 /* Conversion of fixed point operand to floating point value.
*/
553 DEF_RTL_EXPR(FLOAT, "float", "e", RTX_UNARY
)
555 /* With fixed
-point machine mode
:
556 Conversion of floating point operand to fixed point value.
557 Value is defined only when the operand
's value is an integer.
558 With floating-point machine mode (and operand with same mode):
559 Operand is rounded toward zero to produce an integer value
560 represented in floating point. */
561 DEF_RTL_EXPR(FIX, "fix", "e", RTX_UNARY)
563 /* Conversion of unsigned fixed point operand to floating point value. */
564 DEF_RTL_EXPR(UNSIGNED_FLOAT, "unsigned_float", "e", RTX_UNARY)
566 /* With fixed-point machine mode:
567 Conversion of floating point operand to *unsigned* fixed point value.
568 Value is defined only when the operand's value is an integer.
*/
569 DEF_RTL_EXPR(UNSIGNED_FIX
, "unsigned_fix", "e", RTX_UNARY
)
571 /* Conversions involving fractional fixed
-point types without saturation
,
573 fractional to
fractional (of different precision
),
574 signed integer to fractional
,
575 fractional to signed integer
,
576 floating point to fractional
,
577 fractional to floating point.
578 NOTE
: fractional can be either signed or unsigned for conversions.
*/
579 DEF_RTL_EXPR(FRACT_CONVERT
, "fract_convert", "e", RTX_UNARY
)
581 /* Conversions involving fractional fixed
-point types and unsigned integer
582 without saturation
, including
:
583 unsigned integer to fractional
,
584 fractional to unsigned integer.
585 NOTE
: fractional can be either signed or unsigned for conversions.
*/
586 DEF_RTL_EXPR(UNSIGNED_FRACT_CONVERT
, "unsigned_fract_convert", "e", RTX_UNARY
)
588 /* Conversions involving fractional fixed
-point types with saturation
,
590 fractional to
fractional (of different precision
),
591 signed integer to fractional
,
592 floating point to fractional.
593 NOTE
: fractional can be either signed or unsigned for conversions.
*/
594 DEF_RTL_EXPR(SAT_FRACT
, "sat_fract", "e", RTX_UNARY
)
596 /* Conversions involving fractional fixed
-point types and unsigned integer
597 with saturation
, including
:
598 unsigned integer to fractional.
599 NOTE
: fractional can be either signed or unsigned for conversions.
*/
600 DEF_RTL_EXPR(UNSIGNED_SAT_FRACT
, "unsigned_sat_fract", "e", RTX_UNARY
)
603 DEF_RTL_EXPR(ABS, "abs", "e", RTX_UNARY
)
606 DEF_RTL_EXPR(SQRT
, "sqrt", "e", RTX_UNARY
)
609 DEF_RTL_EXPR(BSWAP
, "bswap", "e", RTX_UNARY
)
611 /* Find first bit that is set.
612 Value is
1 + number of trailing zeros in the arg.
,
614 DEF_RTL_EXPR(FFS
, "ffs", "e", RTX_UNARY
)
616 /* Count leading zeros.
*/
617 DEF_RTL_EXPR(CLZ
, "clz", "e", RTX_UNARY
)
619 /* Count trailing zeros.
*/
620 DEF_RTL_EXPR(CTZ
, "ctz", "e", RTX_UNARY
)
622 /* Population
count (number of
1 bits
).
*/
623 DEF_RTL_EXPR(POPCOUNT
, "popcount", "e", RTX_UNARY
)
625 /* Population
parity (number of
1 bits modulo
2).
*/
626 DEF_RTL_EXPR(PARITY
, "parity", "e", RTX_UNARY
)
628 /* Reference to a signed bit
-field of specified size and position.
629 Operand
0 is the memory
unit (usually SImode or QImode
) which
630 contains the field
's first bit. Operand 1 is the width, in bits.
631 Operand 2 is the number of bits in the memory unit before the
632 first bit of this field.
633 If BITS_BIG_ENDIAN is defined, the first bit is the msb and
634 operand 2 counts from the msb of the memory unit.
635 Otherwise, the first bit is the lsb and operand 2 counts from
636 the lsb of the memory unit.
637 This kind of expression can not appear as an lvalue in RTL. */
638 DEF_RTL_EXPR(SIGN_EXTRACT, "sign_extract", "eee", RTX_BITFIELD_OPS)
640 /* Similar for unsigned bit-field.
641 But note! This kind of expression _can_ appear as an lvalue. */
642 DEF_RTL_EXPR(ZERO_EXTRACT, "zero_extract", "eee", RTX_BITFIELD_OPS)
644 /* For RISC machines. These save memory when splitting insns. */
646 /* HIGH are the high-order bits of a constant expression. */
647 DEF_RTL_EXPR(HIGH, "high", "e", RTX_CONST_OBJ)
649 /* LO_SUM is the sum of a register and the low-order bits
650 of a constant expression. */
651 DEF_RTL_EXPR(LO_SUM, "lo_sum", "ee", RTX_OBJ)
653 /* Describes a merge operation between two vector values.
654 Operands 0 and 1 are the vectors to be merged, operand 2 is a bitmask
655 that specifies where the parts of the result are taken from. Set bits
656 indicate operand 0, clear bits indicate operand 1. The parts are defined
657 by the mode of the vectors. */
658 DEF_RTL_EXPR(VEC_MERGE, "vec_merge", "eee", RTX_TERNARY)
660 /* Describes an operation that selects parts of a vector.
661 Operands 0 is the source vector, operand 1 is a PARALLEL that contains
662 a CONST_INT for each of the subparts of the result vector, giving the
663 number of the source subpart that should be stored into it. */
664 DEF_RTL_EXPR(VEC_SELECT, "vec_select", "ee", RTX_BIN_ARITH)
666 /* Describes a vector concat operation. Operands 0 and 1 are the source
667 vectors, the result is a vector that is as long as operands 0 and 1
668 combined and is the concatenation of the two source vectors. */
669 DEF_RTL_EXPR(VEC_CONCAT, "vec_concat", "ee", RTX_BIN_ARITH)
671 /* Describes an operation that converts a small vector into a larger one by
672 duplicating the input values. The output vector mode must have the same
673 submodes as the input vector mode, and the number of output parts must be
674 an integer multiple of the number of input parts. */
675 DEF_RTL_EXPR(VEC_DUPLICATE, "vec_duplicate", "e", RTX_UNARY)
677 /* Addition with signed saturation */
678 DEF_RTL_EXPR(SS_PLUS, "ss_plus", "ee", RTX_COMM_ARITH)
680 /* Addition with unsigned saturation */
681 DEF_RTL_EXPR(US_PLUS, "us_plus", "ee", RTX_COMM_ARITH)
683 /* Operand 0 minus operand 1, with signed saturation. */
684 DEF_RTL_EXPR(SS_MINUS, "ss_minus", "ee", RTX_BIN_ARITH)
686 /* Negation with signed saturation. */
687 DEF_RTL_EXPR(SS_NEG, "ss_neg", "e", RTX_UNARY)
688 /* Negation with unsigned saturation. */
689 DEF_RTL_EXPR(US_NEG, "us_neg", "e", RTX_UNARY)
691 /* Absolute value with signed saturation. */
692 DEF_RTL_EXPR(SS_ABS, "ss_abs", "e", RTX_UNARY)
694 /* Shift left with signed saturation. */
695 DEF_RTL_EXPR(SS_ASHIFT, "ss_ashift", "ee", RTX_BIN_ARITH)
697 /* Shift left with unsigned saturation. */
698 DEF_RTL_EXPR(US_ASHIFT, "us_ashift", "ee", RTX_BIN_ARITH)
700 /* Operand 0 minus operand 1, with unsigned saturation. */
701 DEF_RTL_EXPR(US_MINUS, "us_minus", "ee", RTX_BIN_ARITH)
703 /* Signed saturating truncate. */
704 DEF_RTL_EXPR(SS_TRUNCATE, "ss_truncate", "e", RTX_UNARY)
706 /* Unsigned saturating truncate. */
707 DEF_RTL_EXPR(US_TRUNCATE, "us_truncate", "e", RTX_UNARY)
709 /* Floating point multiply/add combined instruction. */
710 DEF_RTL_EXPR(FMA, "fma", "eee", RTX_TERNARY)
712 /* Information about the variable and its location. */
713 /* Changed 'te
' to 'tei
'; the 'i
' field is for recording
714 initialization status of variables. */
715 DEF_RTL_EXPR(VAR_LOCATION, "var_location", "tei", RTX_EXTRA)
717 /* Used in VAR_LOCATION for a pointer to a decl that is no longer
719 DEF_RTL_EXPR(DEBUG_IMPLICIT_PTR, "debug_implicit_ptr", "t", RTX_OBJ)
721 /* All expressions from this point forward appear only in machine
723 #ifdef GENERATOR_FILE
725 /* Pattern-matching operators: */
727 /* Use the function named by the second arg (the string)
728 as a predicate; if matched, store the structure that was matched
729 in the operand table at index specified by the first arg (the integer).
730 If the second arg is the null string, the structure is just stored.
732 A third string argument indicates to the register allocator restrictions
733 on where the operand can be allocated.
735 If the target needs no restriction on any instruction this field should
738 The string is prepended by:
739 '=' to indicate the operand is only written to.
740 '+' to indicate the operand is both read and written to.
742 Each character in the string represents an allocable class for an operand.
743 'g
' indicates the operand can be any valid class.
744 'i
' indicates the operand can be immediate (in the instruction) data.
745 'r
' indicates the operand can be in a register.
746 'm
' indicates the operand can be in memory.
747 'o
' a subset of the 'm
' class. Those memory addressing modes that
748 can be offset at compile time (have a constant added to them).
750 Other characters indicate target dependent operand classes and
751 are described in each target's machine description.
753 For instructions with more than one operand
, sets of classes can be
754 separated by a comma to indicate the appropriate multi
-operand constraints.
755 There must be a
1 to
1 correspondence between these sets of classes in
756 all operands for an instruction.
758 DEF_RTL_EXPR(MATCH_OPERAND
, "match_operand", "iss", RTX_MATCH
)
760 /* Match a SCRATCH or a register. When used to generate rtl
, a
761 SCRATCH is generated. As for MATCH_OPERAND
, the mode specifies
762 the desired mode and the first argument is the operand number.
763 The second argument is the constraint.
*/
764 DEF_RTL_EXPR(MATCH_SCRATCH
, "match_scratch", "is", RTX_MATCH
)
766 /* Apply a predicate
, AND match recursively the operands of the rtx.
767 Operand
0 is the operand
-number
, as in match_operand.
768 Operand
1 is a predicate to
apply (as a string
, a function name
).
769 Operand
2 is a vector of expressions
, each of which must match
770 one subexpression of the rtx this construct is matching.
*/
771 DEF_RTL_EXPR(MATCH_OPERATOR
, "match_operator", "isE", RTX_MATCH
)
773 /* Match a PARALLEL of arbitrary length. The predicate is applied
774 to the PARALLEL and the initial expressions in the PARALLEL are matched.
775 Operand
0 is the operand
-number
, as in match_operand.
776 Operand
1 is a predicate to apply to the PARALLEL.
777 Operand
2 is a vector of expressions
, each of which must match the
778 corresponding element in the PARALLEL.
*/
779 DEF_RTL_EXPR(MATCH_PARALLEL
, "match_parallel", "isE", RTX_MATCH
)
781 /* Match only something equal to what is stored in the operand table
782 at the index specified by the argument. Use with MATCH_OPERAND.
*/
783 DEF_RTL_EXPR(MATCH_DUP
, "match_dup", "i", RTX_MATCH
)
785 /* Match only something equal to what is stored in the operand table
786 at the index specified by the argument. Use with MATCH_OPERATOR.
*/
787 DEF_RTL_EXPR(MATCH_OP_DUP
, "match_op_dup", "iE", RTX_MATCH
)
789 /* Match only something equal to what is stored in the operand table
790 at the index specified by the argument. Use with MATCH_PARALLEL.
*/
791 DEF_RTL_EXPR(MATCH_PAR_DUP
, "match_par_dup", "iE", RTX_MATCH
)
793 /* Appears only in define_predicate
/define_special_predicate
794 expressions. Evaluates true only if the operand has an RTX code
795 from the set given by the
argument (a comma
-separated list
). If the
796 second argument is present and nonempty
, it is a sequence of digits
797 and
/or letters which indicates the subexpression to test
, using the
798 same syntax as genextract
/genrecog
's location strings: 0-9 for
799 XEXP (op, n), a-z for XVECEXP (op, 0, n); each character applies to
800 the result of the one before it. */
801 DEF_RTL_EXPR(MATCH_CODE, "match_code", "ss", RTX_MATCH)
803 /* Appears only in define_predicate/define_special_predicate
804 expressions. The argument is a C expression to be injected at this
805 point in the predicate formula. */
806 DEF_RTL_EXPR(MATCH_TEST, "match_test", "s", RTX_MATCH)
808 /* Insn (and related) definitions. */
810 /* Definition of the pattern for one kind of instruction.
812 0: names this instruction.
813 If the name is the null string, the instruction is in the
814 machine description just to be recognized, and will never be emitted by
815 the tree to rtl expander.
817 2: is a string which is a C expression
818 giving an additional condition for recognizing this pattern.
819 A null string means no extra condition.
820 3: is the action to execute if this pattern is matched.
821 If this assembler code template starts with a * then it is a fragment of
822 C code to run to decide on a template to use. Otherwise, it is the
824 4: optionally, a vector of attributes for this insn.
826 DEF_RTL_EXPR(DEFINE_INSN, "define_insn", "sEsTV", RTX_EXTRA)
828 /* Definition of a peephole optimization.
829 1st operand: vector of insn patterns to match
830 2nd operand: C expression that must be true
831 3rd operand: template or C code to produce assembler output.
832 4: optionally, a vector of attributes for this insn.
834 This form is deprecated; use define_peephole2 instead. */
835 DEF_RTL_EXPR(DEFINE_PEEPHOLE, "define_peephole", "EsTV", RTX_EXTRA)
837 /* Definition of a split operation.
838 1st operand: insn pattern to match
839 2nd operand: C expression that must be true
840 3rd operand: vector of insn patterns to place into a SEQUENCE
841 4th operand: optionally, some C code to execute before generating the
842 insns. This might, for example, create some RTX's and store them in
843 elements of `recog_data.operand
' for use by the vector of
845 (`operands' is an alias here for `recog_data.operand
'). */
846 DEF_RTL_EXPR(DEFINE_SPLIT, "define_split", "EsES", RTX_EXTRA)
848 /* Definition of an insn and associated split.
849 This is the concatenation, with a few modifications, of a define_insn
850 and a define_split which share the same pattern.
852 0: names this instruction.
853 If the name is the null string, the instruction is in the
854 machine description just to be recognized, and will never be emitted by
855 the tree to rtl expander.
857 2: is a string which is a C expression
858 giving an additional condition for recognizing this pattern.
859 A null string means no extra condition.
860 3: is the action to execute if this pattern is matched.
861 If this assembler code template starts with a * then it is a fragment of
862 C code to run to decide on a template to use. Otherwise, it is the
864 4: C expression that must be true for split. This may start with "&&"
865 in which case the split condition is the logical and of the insn
866 condition and what follows the "&&" of this operand.
867 5: vector of insn patterns to place into a SEQUENCE
868 6: optionally, some C code to execute before generating the
869 insns. This might, for example, create some RTX's and store them in
870 elements of `recog_data.operand
' for use by the vector of
872 (`operands' is an alias here for `recog_data.operand
').
873 7: optionally, a vector of attributes for this insn. */
874 DEF_RTL_EXPR(DEFINE_INSN_AND_SPLIT, "define_insn_and_split", "sEsTsESV", RTX_EXTRA)
876 /* Definition of an RTL peephole operation.
877 Follows the same arguments as define_split. */
878 DEF_RTL_EXPR(DEFINE_PEEPHOLE2, "define_peephole2", "EsES", RTX_EXTRA)
880 /* Define how to generate multiple insns for a standard insn name.
881 1st operand: the insn name.
882 2nd operand: vector of insn-patterns.
883 Use match_operand to substitute an element of `recog_data.operand'.
884 3rd operand
: C expression that must be true for this to be available.
885 This may not test any operands.
886 4th operand
: Extra C code to execute before generating the insns.
887 This might
, for example
, create some RTX
's and store them in
888 elements of `recog_data.operand' for use by the vector of
890 (`operands
' is an alias here for `recog_data.operand').
*/
891 DEF_RTL_EXPR(DEFINE_EXPAND
, "define_expand", "sEss", RTX_EXTRA
)
893 /* Define a requirement for delay slots.
894 1st operand
: Condition involving insn attributes that
, if true
,
895 indicates that the insn requires the number of delay slots
897 2nd operand
: Vector whose length is the three times the number of delay
899 Each entry gives three conditions
, each involving attributes.
900 The first must be true for an insn to occupy that delay slot
901 location. The second is true for all insns that can be
902 annulled if the branch is true and the third is true for all
903 insns that can be annulled if the branch is false.
905 Multiple DEFINE_DELAYs may be present. They indicate differing
906 requirements for delay slots.
*/
907 DEF_RTL_EXPR(DEFINE_DELAY
, "define_delay", "eE", RTX_EXTRA
)
909 /* Define attribute computation for `asm
' instructions. */
910 DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES, "define_asm_attributes", "V", RTX_EXTRA)
912 /* Definition of a conditional execution meta operation. Automatically
913 generates new instances of DEFINE_INSN, selected by having attribute
914 "predicable" true. The new pattern will contain a COND_EXEC and the
915 predicate at top-level.
918 0: The predicate pattern. The top-level form should match a
919 relational operator. Operands should have only one alternative.
920 1: A C expression giving an additional condition for recognizing
921 the generated pattern.
922 2: A template or C code to produce assembler output. */
923 DEF_RTL_EXPR(DEFINE_COND_EXEC, "define_cond_exec", "Ess", RTX_EXTRA)
925 /* Definition of an operand predicate. The difference between
926 DEFINE_PREDICATE and DEFINE_SPECIAL_PREDICATE is that genrecog will
927 not warn about a match_operand with no mode if it has a predicate
928 defined with DEFINE_SPECIAL_PREDICATE.
931 0: The name of the predicate.
932 1: A boolean expression which computes whether or not the predicate
933 matches. This expression can use IOR, AND, NOT, MATCH_OPERAND,
934 MATCH_CODE, and MATCH_TEST. It must be specific enough that genrecog
935 can calculate the set of RTX codes that can possibly match.
936 2: A C function body which must return true for the predicate to match.
937 Optional. Use this when the test is too complicated to fit into a
938 match_test expression. */
939 DEF_RTL_EXPR(DEFINE_PREDICATE, "define_predicate", "ses", RTX_EXTRA)
940 DEF_RTL_EXPR(DEFINE_SPECIAL_PREDICATE, "define_special_predicate", "ses", RTX_EXTRA)
942 /* Definition of a register operand constraint. This simply maps the
943 constraint string to a register class.
946 0: The name of the constraint (often, but not always, a single letter).
947 1: A C expression which evaluates to the appropriate register class for
948 this constraint. If this is not just a constant, it should look only
949 at -m switches and the like.
950 2: A docstring for this constraint, in Texinfo syntax; not currently
951 used, in future will be incorporated into the manual's list of
952 machine
-specific operand constraints.
*/
953 DEF_RTL_EXPR(DEFINE_REGISTER_CONSTRAINT
, "define_register_constraint", "sss", RTX_EXTRA
)
955 /* Definition of a non
-register operand constraint. These look at the
956 operand and decide whether it fits the constraint.
958 DEFINE_CONSTRAINT gets no special treatment if it fails to match.
959 It is appropriate for constant
-only constraints
, and most others.
961 DEFINE_MEMORY_CONSTRAINT tells reload that this constraint can be made
962 to match
, if it doesn
't already, by converting the operand to the form
963 (mem (reg X)) where X is a base register. It is suitable for constraints
964 that describe a subset of all memory references.
966 DEFINE_ADDRESS_CONSTRAINT tells reload that this constraint can be made
967 to match, if it doesn't already
, by converting the operand to the form
968 (reg X
) where X is a base register. It is suitable for constraints that
969 describe a subset of all address references.
971 When in doubt
, use plain DEFINE_CONSTRAINT.
974 0: The name of the
constraint (often
, but not always
, a single letter
).
975 1: A docstring for this constraint
, in Texinfo syntax
; not currently
976 used
, in future will be incorporated into the manual
's list of
977 machine-specific operand constraints.
978 2: A boolean expression which computes whether or not the constraint
979 matches. It should follow the same rules as a define_predicate
980 expression, including the bit about specifying the set of RTX codes
981 that could possibly match. MATCH_TEST subexpressions may make use of
983 `op' - the RTL object defining the operand.
984 `mode
' - the mode of `op'.
985 `ival
' - INTVAL(op), if op is a CONST_INT.
986 `hval' - CONST_DOUBLE_HIGH(op
), if op is an integer CONST_DOUBLE.
987 `lval
' - CONST_DOUBLE_LOW(op), if op is an integer CONST_DOUBLE.
988 `rval' - CONST_DOUBLE_REAL_VALUE(op
), if op is a floating
-point
990 Do not use ival
/hval
/lval
/rval if op is not the appropriate kind of
992 DEF_RTL_EXPR(DEFINE_CONSTRAINT
, "define_constraint", "sse", RTX_EXTRA
)
993 DEF_RTL_EXPR(DEFINE_MEMORY_CONSTRAINT
, "define_memory_constraint", "sse", RTX_EXTRA
)
994 DEF_RTL_EXPR(DEFINE_ADDRESS_CONSTRAINT
, "define_address_constraint", "sse", RTX_EXTRA
)
997 /* Constructions for CPU pipeline description described by NDFAs.
*/
999 /* (define_cpu_unit string
[string
]) describes cpu functional
1000 units (separated by comma
).
1002 1st operand
: Names of cpu functional units.
1003 2nd operand
: Name of
automaton (see comments for DEFINE_AUTOMATON
).
1005 All define_reservations
, define_cpu_units
, and
1006 define_query_cpu_units should have unique names which may not be
1008 DEF_RTL_EXPR(DEFINE_CPU_UNIT
, "define_cpu_unit", "sS", RTX_EXTRA
)
1010 /* (define_query_cpu_unit string
[string
]) describes cpu functional
1011 units analogously to define_cpu_unit. The reservation of such
1012 units can be queried for automaton state.
*/
1013 DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT
, "define_query_cpu_unit", "sS", RTX_EXTRA
)
1015 /* (exclusion_set string string
) means that each CPU functional unit
1016 in the first string can not be reserved simultaneously with any
1017 unit whose name is in the second string and vise versa. CPU units
1018 in the string are separated by commas. For example
, it is useful
1019 for description CPU with fully pipelined floating point functional
1020 unit which can execute simultaneously only single floating point
1021 insns or only double floating point insns. All CPU functional
1022 units in a set should belong to the same automaton.
*/
1023 DEF_RTL_EXPR(EXCLUSION_SET
, "exclusion_set", "ss", RTX_EXTRA
)
1025 /* (presence_set string string
) means that each CPU functional unit in
1026 the first string can not be reserved unless at least one of pattern
1027 of units whose names are in the second string is reserved. This is
1028 an asymmetric relation. CPU units or unit patterns in the strings
1029 are separated by commas. Pattern is one unit name or unit names
1030 separated by white
-spaces.
1032 For example
, it is useful for description that slot1 is reserved
1033 after slot0 reservation for a VLIW processor. We could describe it
1034 by the following construction
1036 (presence_set
"slot1" "slot0")
1038 Or slot1 is reserved only after slot0 and unit b0 reservation. In
1039 this case we could write
1041 (presence_set
"slot1" "slot0 b0")
1043 All CPU functional units in a set should belong to the same
1045 DEF_RTL_EXPR(PRESENCE_SET
, "presence_set", "ss", RTX_EXTRA
)
1047 /* (final_presence_set string string
) is analogous to `presence_set
'.
1048 The difference between them is when checking is done. When an
1049 instruction is issued in given automaton state reflecting all
1050 current and planned unit reservations, the automaton state is
1051 changed. The first state is a source state, the second one is a
1052 result state. Checking for `presence_set' is done on the source
1053 state reservation
, checking for `final_presence_set
' is done on the
1054 result reservation. This construction is useful to describe a
1055 reservation which is actually two subsequent reservations. For
1058 (presence_set "slot1" "slot0")
1060 the following insn will be never issued (because slot1 requires
1061 slot0 which is absent in the source state).
1063 (define_reservation "insn_and_nop" "slot0 + slot1")
1065 but it can be issued if we use analogous `final_presence_set'.
*/
1066 DEF_RTL_EXPR(FINAL_PRESENCE_SET
, "final_presence_set", "ss", RTX_EXTRA
)
1068 /* (absence_set string string
) means that each CPU functional unit in
1069 the first string can be reserved only if each pattern of units
1070 whose names are in the second string is not reserved. This is an
1071 asymmetric
relation (actually exclusion set is analogous to this
1072 one but it is symmetric
). CPU units or unit patterns in the string
1073 are separated by commas. Pattern is one unit name or unit names
1074 separated by white
-spaces.
1076 For example
, it is useful for description that slot0 can not be
1077 reserved after slot1 or slot2 reservation for a VLIW processor. We
1078 could describe it by the following construction
1080 (absence_set
"slot2" "slot0, slot1")
1082 Or slot2 can not be reserved if slot0 and unit b0 are reserved or
1083 slot1 and unit b1 are reserved . In this case we could write
1085 (absence_set
"slot2" "slot0 b0, slot1 b1")
1087 All CPU functional units in a set should to belong the same
1089 DEF_RTL_EXPR(ABSENCE_SET
, "absence_set", "ss", RTX_EXTRA
)
1091 /* (final_absence_set string string
) is analogous to `absence_set
' but
1092 checking is done on the result (state) reservation. See comments
1093 for `final_presence_set'.
*/
1094 DEF_RTL_EXPR(FINAL_ABSENCE_SET
, "final_absence_set", "ss", RTX_EXTRA
)
1096 /* (define_bypass number out_insn_names in_insn_names
) names bypass
1097 with given
latency (the first number
) from insns given by the first
1098 string (see define_insn_reservation
) into insns given by the second
1099 string. Insn names in the strings are separated by commas. The
1100 third operand is optional name of function which is additional
1101 guard for the bypass. The function will get the two insns as
1102 parameters. If the function returns zero the bypass will be
1103 ignored for this case. Additional guard is necessary to recognize
1104 complicated bypasses
, e.g. when consumer is load address. If there
1105 are more one bypass with the same output and input insns
, the
1106 chosen bypass is the first bypass with a guard in description whose
1107 guard function returns nonzero. If there is no such bypass
, then
1108 bypass without the guard function is chosen.
*/
1109 DEF_RTL_EXPR(DEFINE_BYPASS
, "define_bypass", "issS", RTX_EXTRA
)
1111 /* (define_automaton string
) describes names of automata generated and
1112 used for pipeline hazards recognition. The names are separated by
1113 comma. Actually it is possibly to generate the single automaton
1114 but unfortunately it can be very large. If we use more one
1115 automata
, the summary size of the automata usually is less than the
1116 single one. The automaton name is used in define_cpu_unit and
1117 define_query_cpu_unit. All automata should have unique names.
*/
1118 DEF_RTL_EXPR(DEFINE_AUTOMATON
, "define_automaton", "s", RTX_EXTRA
)
1120 /* (automata_option string
) describes option for generation of
1121 automata. Currently there are the following options
:
1123 o
"no-minimization" which makes no minimization of automata. This
1124 is only worth to do when we are debugging the description and
1125 need to look more accurately at reservations of states.
1127 o
"time" which means printing additional time statistics about
1128 generation of automata.
1130 o
"v" which means generation of file describing the result
1131 automata. The file has suffix `.dfa
' and can be used for the
1132 description verification and debugging.
1134 o "w" which means generation of warning instead of error for
1135 non-critical errors.
1137 o "ndfa" which makes nondeterministic finite state automata.
1139 o "progress" which means output of a progress bar showing how many
1140 states were generated so far for automaton being processed. */
1141 DEF_RTL_EXPR(AUTOMATA_OPTION, "automata_option", "s", RTX_EXTRA)
1143 /* (define_reservation string string) names reservation (the first
1144 string) of cpu functional units (the 2nd string). Sometimes unit
1145 reservations for different insns contain common parts. In such
1146 case, you can describe common part and use its name (the 1st
1147 parameter) in regular expression in define_insn_reservation. All
1148 define_reservations, define_cpu_units, and define_query_cpu_units
1149 should have unique names which may not be "nothing". */
1150 DEF_RTL_EXPR(DEFINE_RESERVATION, "define_reservation", "ss", RTX_EXTRA)
1152 /* (define_insn_reservation name default_latency condition regexpr)
1153 describes reservation of cpu functional units (the 3nd operand) for
1154 instruction which is selected by the condition (the 2nd parameter).
1155 The first parameter is used for output of debugging information.
1156 The reservations are described by a regular expression according
1157 the following syntax:
1159 regexp = regexp "," oneof
1162 oneof = oneof "|" allof
1165 allof = allof "+" repeat
1168 repeat = element "*" number
1171 element = cpu_function_unit_name
1177 1. "," is used for describing start of the next cycle in
1180 2. "|" is used for describing the reservation described by the
1181 first regular expression *or* the reservation described by the
1182 second regular expression *or* etc.
1184 3. "+" is used for describing the reservation described by the
1185 first regular expression *and* the reservation described by the
1186 second regular expression *and* etc.
1188 4. "*" is used for convenience and simply means sequence in
1189 which the regular expression are repeated NUMBER times with
1190 cycle advancing (see ",").
1192 5. cpu functional unit name which means its reservation.
1194 6. reservation name -- see define_reservation.
1196 7. string "nothing" means no units reservation. */
1198 DEF_RTL_EXPR(DEFINE_INSN_RESERVATION, "define_insn_reservation", "sies", RTX_EXTRA)
1200 /* Expressions used for insn attributes. */
1202 /* Definition of an insn attribute.
1203 1st operand: name of the attribute
1204 2nd operand: comma-separated list of possible attribute values
1205 3rd operand: expression for the default value of the attribute. */
1206 DEF_RTL_EXPR(DEFINE_ATTR, "define_attr", "sse", RTX_EXTRA)
1208 /* Definition of an insn attribute that uses an existing enumerated type.
1209 1st operand: name of the attribute
1210 2nd operand: the name of the enumerated type
1211 3rd operand: expression for the default value of the attribute. */
1212 DEF_RTL_EXPR(DEFINE_ENUM_ATTR, "define_enum_attr", "sse", RTX_EXTRA)
1214 /* Marker for the name of an attribute. */
1215 DEF_RTL_EXPR(ATTR, "attr", "s", RTX_EXTRA)
1217 /* For use in the last (optional) operand of DEFINE_INSN or DEFINE_PEEPHOLE and
1218 in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that
1221 (set_attr "name" "value") is equivalent to
1222 (set (attr "name") (const_string "value")) */
1223 DEF_RTL_EXPR(SET_ATTR, "set_attr", "ss", RTX_EXTRA)
1225 /* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE, this can be used to
1226 specify that attribute values are to be assigned according to the
1227 alternative matched.
1229 The following three expressions are equivalent:
1231 (set (attr "att") (cond [(eq_attrq "alternative" "1") (const_string "a1")
1232 (eq_attrq "alternative" "2") (const_string "a2")]
1233 (const_string "a3")))
1234 (set_attr_alternative "att" [(const_string "a1") (const_string "a2")
1235 (const_string "a3")])
1236 (set_attr "att" "a1,a2,a3")
1238 DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE, "set_attr_alternative", "sE", RTX_EXTRA)
1240 /* A conditional expression true if the value of the specified attribute of
1241 the current insn equals the specified value. The first operand is the
1242 attribute name and the second is the comparison value. */
1243 DEF_RTL_EXPR(EQ_ATTR, "eq_attr", "ss", RTX_EXTRA)
1245 /* A special case of the above representing a set of alternatives. The first
1246 operand is bitmap of the set, the second one is the default value. */
1247 DEF_RTL_EXPR(EQ_ATTR_ALT, "eq_attr_alt", "ii", RTX_EXTRA)
1249 /* A conditional expression which is true if the specified flag is
1250 true for the insn being scheduled in reorg.
1252 genattr.c defines the following flags which can be tested by
1253 (attr_flag "foo") expressions in eligible_for_delay.
1255 forward, backward, very_likely, likely, very_unlikely, and unlikely. */
1257 DEF_RTL_EXPR (ATTR_FLAG, "attr_flag", "s", RTX_EXTRA)
1259 /* General conditional. The first operand is a vector composed of pairs of
1260 expressions. The first element of each pair is evaluated, in turn.
1261 The value of the conditional is the second expression of the first pair
1262 whose first expression evaluates nonzero. If none of the expressions is
1263 true, the second operand will be used as the value of the conditional. */
1264 DEF_RTL_EXPR(COND, "cond", "Ee", RTX_EXTRA)
1266 #endif /* GENERATOR_FILE */