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
6   Free Software Foundation, Inc.
7
8This file is part of GCC.
9
10GCC is free software; you can redistribute it and/or modify it under
11the terms of the GNU General Public License as published by the Free
12Software Foundation; either version 2, or (at your option) any later
13version.
14
15GCC is distributed in the hope that it will be useful, but WITHOUT ANY
16WARRANTY; without even the implied warranty of MERCHANTABILITY or
17FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
18for more details.
19
20You should have received a copy of the GNU General Public License
21along with GCC; see the file COPYING.  If not, write to the Free
22Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
2302110-1301, USA.  */
24
25
26/* Expression definitions and descriptions for all targets are in this file.
27   Some will not be used for some targets.
28
29   The fields in the cpp macro call "DEF_RTL_EXPR()"
30   are used to create declarations in the C source of the compiler.
31
32   The fields are:
33
34   1.  The internal name of the rtx used in the C source.
35   It is a tag in the enumeration "enum rtx_code" defined in "rtl.h".
36   By convention these are in UPPER_CASE.
37
38   2.  The name of the rtx in the external ASCII format read by
39   read_rtx(), and printed by print_rtx().
40   These names are stored in rtx_name[].
41   By convention these are the internal (field 1) names in lower_case.
42
43   3.  The print format, and type of each rtx->u.fld[] (field) in this rtx.
44   These formats are stored in rtx_format[].
45   The meaning of the formats is documented in front of this array in rtl.c
46
47   4.  The class of the rtx.  These are stored in rtx_class and are accessed
48   via the GET_RTX_CLASS macro.  They are defined as follows:
49
50     RTX_CONST_OBJ
51         an rtx code that can be used to represent a constant object
52         (e.g, CONST_INT)
53     RTX_OBJ
54         an rtx code that can be used to represent an object (e.g, REG, MEM)
55     RTX_COMPARE
56         an rtx code for a comparison (e.g, LT, GT)
57     RTX_COMM_COMPARE
58         an rtx code for a commutative comparison (e.g, EQ, NE, ORDERED)
59     RTX_UNARY
60         an rtx code for a unary arithmetic expression (e.g, NEG, NOT)
61     RTX_COMM_ARITH
62         an rtx code for a commutative binary operation (e.g,, PLUS, MULT)
63     RTX_TERNARY
64         an rtx code for a non-bitfield three input operation (IF_THEN_ELSE)
65     RTX_BIN_ARITH
66         an rtx code for a non-commutative binary operation (e.g., MINUS, DIV)
67     RTX_BITFIELD_OPS
68         an rtx code for a bit-field operation (ZERO_EXTRACT, SIGN_EXTRACT)
69     RTX_INSN
70         an rtx code for a machine insn (INSN, JUMP_INSN, CALL_INSN)
71     RTX_MATCH
72         an rtx code for something that matches in insns (e.g, MATCH_DUP)
73     RTX_AUTOINC
74         an rtx code for autoincrement addressing modes (e.g. POST_DEC)
75     RTX_EXTRA
76         everything else
77
78   All of the expressions that appear only in machine descriptions,
79   not in RTL used by the compiler itself, are at the end of the file.  */
80
81/* Unknown, or no such operation; the enumeration constant should have
82   value zero.  */
83DEF_RTL_EXPR(UNKNOWN, "UnKnown", "*", RTX_EXTRA)
84
85/* ---------------------------------------------------------------------
86   Expressions used in constructing lists.
87   --------------------------------------------------------------------- */
88
89/* a linked list of expressions */
90DEF_RTL_EXPR(EXPR_LIST, "expr_list", "ee", RTX_EXTRA)
91
92/* a linked list of instructions.
93   The insns are represented in print by their uids.  */
94DEF_RTL_EXPR(INSN_LIST, "insn_list", "ue", RTX_EXTRA)
95
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).  */
99DEF_RTL_EXPR(DEPS_LIST, "deps_list", "uei", RTX_EXTRA)
100
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.  */
105DEF_RTL_EXPR(SEQUENCE, "sequence", "E", RTX_EXTRA)
106
107/* Refers to the address of its argument.  This is only used in alias.c.  */
108DEF_RTL_EXPR(ADDRESS, "address", "e", RTX_MATCH)
109
110/* ----------------------------------------------------------------------
111   Expression types used for things in the instruction chain.
112
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[].
117
118   ---------------------------------------------------------------------- */
119
120/* An instruction that cannot jump.  */
121DEF_RTL_EXPR(INSN, "insn", "iuuBieiee", RTX_INSN)
122
123/* An instruction that can possibly jump.
124   Fields ( rtx->u.fld[] ) have exact same meaning as INSN's.  */
125DEF_RTL_EXPR(JUMP_INSN, "jump_insn", "iuuBieiee0", RTX_INSN)
126
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.  */
132DEF_RTL_EXPR(CALL_INSN, "call_insn", "iuuBieieee", RTX_INSN)
133
134/* A marker that indicates that control will not flow through.  */
135DEF_RTL_EXPR(BARRIER, "barrier", "iuu000000", RTX_EXTRA)
136
137/* Holds a label that is followed by instructions.
138   Operand:
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   7: is the user-given name of the label, if any.  */
143DEF_RTL_EXPR(CODE_LABEL, "code_label", "iuuB00is", RTX_EXTRA)
144
145#ifdef USE_MAPPED_LOCATION
146/* Say where in the code a source line starts, for symbol table's sake.
147   Operand:
148   4: unused if line number > 0, note-specific data otherwise.
149   5: line number if > 0, enum note_insn otherwise.
150   6: CODE_LABEL_NUMBER if line number == NOTE_INSN_DELETED_LABEL.  */
151#else
152/* Say where in the code a source line starts, for symbol table's sake.
153   Operand:
154   4: filename, if line number > 0, note-specific data otherwise.
155   5: line number if > 0, enum note_insn otherwise.
156   6: unique number if line number == note_insn_deleted_label.  */
157#endif
158DEF_RTL_EXPR(NOTE, "note", "iuuB0ni", RTX_EXTRA)
159
160/* ----------------------------------------------------------------------
161   Top level constituents of INSN, JUMP_INSN and CALL_INSN.
162   ---------------------------------------------------------------------- */
163
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).
167
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.  */
171DEF_RTL_EXPR(COND_EXEC, "cond_exec", "ee", RTX_EXTRA)
172
173/* Several operations to be done in parallel (perhaps under COND_EXEC).  */
174DEF_RTL_EXPR(PARALLEL, "parallel", "E", RTX_EXTRA)
175
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.  */
182DEF_RTL_EXPR(ASM_INPUT, "asm_input", "s", RTX_EXTRA)
183
184#ifdef USE_MAPPED_LOCATION
185/* An assembler instruction with operands.
186   1st operand is the instruction template.
187   2nd operand is the constraint for the output.
188   3rd operand is the number of the output this expression refers to.
189     When an insn stores more than one value, a separate ASM_OPERANDS
190     is made for each output; this integer distinguishes them.
191   4th is a vector of values of input operands.
192   5th is a vector of modes and constraints for the input operands.
193     Each element is an ASM_INPUT containing a constraint string
194     and whose mode indicates the mode of the input operand.
195   6th is the source line number.  */
196DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEi", RTX_EXTRA)
197#else
198/* An assembler instruction with operands.
199   1st operand is the instruction template.
200   2nd operand is the constraint for the output.
201   3rd operand is the number of the output this expression refers to.
202     When an insn stores more than one value, a separate ASM_OPERANDS
203     is made for each output; this integer distinguishes them.
204   4th is a vector of values of input operands.
205   5th is a vector of modes and constraints for the input operands.
206     Each element is an ASM_INPUT containing a constraint string
207     and whose mode indicates the mode of the input operand.
208   6th is the name of the containing source file.
209   7th is the source line number.  */
210DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEsi", RTX_EXTRA)
211#endif
212
213/* A machine-specific operation.
214   1st operand is a vector of operands being used by the operation so that
215     any needed reloads can be done.
216   2nd operand is a unique value saying which of a number of machine-specific
217     operations is to be performed.
218   (Note that the vector must be the first operand because of the way that
219   genrecog.c record positions within an insn.)
220   This can occur all by itself in a PATTERN, as a component of a PARALLEL,
221   or inside an expression.  */
222DEF_RTL_EXPR(UNSPEC, "unspec", "Ei", RTX_EXTRA)
223
224/* Similar, but a volatile operation and one which may trap.  */
225DEF_RTL_EXPR(UNSPEC_VOLATILE, "unspec_volatile", "Ei", RTX_EXTRA)
226
227/* Vector of addresses, stored as full words.  */
228/* Each element is a LABEL_REF to a CODE_LABEL whose address we want.  */
229DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", RTX_EXTRA)
230
231/* Vector of address differences X0 - BASE, X1 - BASE, ...
232   First operand is BASE; the vector contains the X's.
233   The machine mode of this rtx says how much space to leave
234   for each difference and is adjusted by branch shortening if
235   CASE_VECTOR_SHORTEN_MODE is defined.
236   The third and fourth operands store the target labels with the
237   minimum and maximum addresses respectively.
238   The fifth operand stores flags for use by branch shortening.
239  Set at the start of shorten_branches:
240   min_align: the minimum alignment for any of the target labels.
241   base_after_vec: true iff BASE is after the ADDR_DIFF_VEC.
242   min_after_vec: true iff minimum addr target label is after the ADDR_DIFF_VEC.
243   max_after_vec: true iff maximum addr target label is after the ADDR_DIFF_VEC.
244   min_after_base: true iff minimum address target label is after BASE.
245   max_after_base: true iff maximum address target label is after BASE.
246  Set by the actual branch shortening process:
247   offset_unsigned: true iff offsets have to be treated as unsigned.
248   scale: scaling that is necessary to make offsets fit into the mode.
249
250   The third, fourth and fifth operands are only valid when
251   CASE_VECTOR_SHORTEN_MODE is defined, and only in an optimizing
252   compilations.  */
253
254DEF_RTL_EXPR(ADDR_DIFF_VEC, "addr_diff_vec", "eEee0", RTX_EXTRA)
255
256/* Memory prefetch, with attributes supported on some targets.
257   Operand 1 is the address of the memory to fetch.
258   Operand 2 is 1 for a write access, 0 otherwise.
259   Operand 3 is the level of temporal locality; 0 means there is no
260   temporal locality and 1, 2, and 3 are for increasing levels of temporal
261   locality.
262
263   The attributes specified by operands 2 and 3 are ignored for targets
264   whose prefetch instructions do not support them.  */
265DEF_RTL_EXPR(PREFETCH, "prefetch", "eee", RTX_EXTRA)
266
267/* ----------------------------------------------------------------------
268   At the top level of an instruction (perhaps under PARALLEL).
269   ---------------------------------------------------------------------- */
270
271/* Assignment.
272   Operand 1 is the location (REG, MEM, PC, CC0 or whatever) assigned to.
273   Operand 2 is the value stored there.
274   ALL assignment must use SET.
275   Instructions that do multiple assignments must use multiple SET,
276   under PARALLEL.  */
277DEF_RTL_EXPR(SET, "set", "ee", RTX_EXTRA)
278
279/* Indicate something is used in a way that we don't want to explain.
280   For example, subroutine calls will use the register
281   in which the static chain is passed.  */
282DEF_RTL_EXPR(USE, "use", "e", RTX_EXTRA)
283
284/* Indicate something is clobbered in a way that we don't want to explain.
285   For example, subroutine calls will clobber some physical registers
286   (the ones that are by convention not saved).  */
287DEF_RTL_EXPR(CLOBBER, "clobber", "e", RTX_EXTRA)
288
289/* Call a subroutine.
290   Operand 1 is the address to call.
291   Operand 2 is the number of arguments.  */
292
293DEF_RTL_EXPR(CALL, "call", "ee", RTX_EXTRA)
294
295/* Return from a subroutine.  */
296
297DEF_RTL_EXPR(RETURN, "return", "", RTX_EXTRA)
298
299/* Conditional trap.
300   Operand 1 is the condition.
301   Operand 2 is the trap code.
302   For an unconditional trap, make the condition (const_int 1).  */
303DEF_RTL_EXPR(TRAP_IF, "trap_if", "ee", RTX_EXTRA)
304
305/* Placeholder for _Unwind_Resume before we know if a function call
306   or a branch is needed.  Operand 1 is the exception region from
307   which control is flowing.  */
308DEF_RTL_EXPR(RESX, "resx", "i", RTX_EXTRA)
309
310/* ----------------------------------------------------------------------
311   Primitive values for use in expressions.
312   ---------------------------------------------------------------------- */
313
314/* numeric integer constant */
315DEF_RTL_EXPR(CONST_INT, "const_int", "w", RTX_CONST_OBJ)
316
317/* numeric floating point constant.
318   Operands hold the value.  They are all 'w' and there may be from 2 to 6;
319   see real.h.  */
320DEF_RTL_EXPR(CONST_DOUBLE, "const_double", CONST_DOUBLE_FORMAT, RTX_CONST_OBJ)
321
322/* Describes a vector constant.  */
323DEF_RTL_EXPR(CONST_VECTOR, "const_vector", "E", RTX_CONST_OBJ)
324
325/* String constant.  Used for attributes in machine descriptions and
326   for special cases in DWARF2 debug output.  NOT used for source-
327   language string constants.  */
328DEF_RTL_EXPR(CONST_STRING, "const_string", "s", RTX_OBJ)
329
330/* This is used to encapsulate an expression whose value is constant
331   (such as the sum of a SYMBOL_REF and a CONST_INT) so that it will be
332   recognized as a constant operand rather than by arithmetic instructions.  */
333
334DEF_RTL_EXPR(CONST, "const", "e", RTX_CONST_OBJ)
335
336/* program counter.  Ordinary jumps are represented
337   by a SET whose first operand is (PC).  */
338DEF_RTL_EXPR(PC, "pc", "", RTX_OBJ)
339
340/* Used in the cselib routines to describe a value.  Objects of this
341   kind are only allocated in cselib.c, in an alloc pool instead of
342   in GC memory.  The only operand of a VALUE is a cselib_val_struct.  */
343DEF_RTL_EXPR(VALUE, "value", "0", RTX_OBJ)
344
345/* A register.  The "operand" is the register number, accessed with
346   the REGNO macro.  If this number is less than FIRST_PSEUDO_REGISTER
347   than a hardware register is being referred to.  The second operand
348   holds the original register number - this will be different for a
349   pseudo register that got turned into a hard register.  The third
350   operand points to a reg_attrs structure.
351   This rtx needs to have as many (or more) fields as a MEM, since we
352   can change REG rtx's into MEMs during reload.  */
353DEF_RTL_EXPR(REG, "reg", "i00", RTX_OBJ)
354
355/* A scratch register.  This represents a register used only within a
356   single insn.  It will be turned into a REG during register allocation
357   or reload unless the constraint indicates that the register won't be
358   needed, in which case it can remain a SCRATCH.  This code is
359   marked as having one operand so it can be turned into a REG.  */
360DEF_RTL_EXPR(SCRATCH, "scratch", "0", RTX_OBJ)
361
362/* One word of a multi-word value.
363   The first operand is the complete value; the second says which word.
364   The WORDS_BIG_ENDIAN flag controls whether word number 0
365   (as numbered in a SUBREG) is the most or least significant word.
366
367   This is also used to refer to a value in a different machine mode.
368   For example, it can be used to refer to a SImode value as if it were
369   Qimode, or vice versa.  Then the word number is always 0.  */
370DEF_RTL_EXPR(SUBREG, "subreg", "ei", RTX_EXTRA)
371
372/* This one-argument rtx is used for move instructions
373   that are guaranteed to alter only the low part of a destination.
374   Thus, (SET (SUBREG:HI (REG...)) (MEM:HI ...))
375   has an unspecified effect on the high part of REG,
376   but (SET (STRICT_LOW_PART (SUBREG:HI (REG...))) (MEM:HI ...))
377   is guaranteed to alter only the bits of REG that are in HImode.
378
379   The actual instruction used is probably the same in both cases,
380   but the register constraints may be tighter when STRICT_LOW_PART
381   is in use.  */
382
383DEF_RTL_EXPR(STRICT_LOW_PART, "strict_low_part", "e", RTX_EXTRA)
384
385/* (CONCAT a b) represents the virtual concatenation of a and b
386   to make a value that has as many bits as a and b put together.
387   This is used for complex values.  Normally it appears only
388   in DECL_RTLs and during RTL generation, but not in the insn chain.  */
389DEF_RTL_EXPR(CONCAT, "concat", "ee", RTX_OBJ)
390
391/* A memory location; operand is the address.  The second operand is the
392   alias set to which this MEM belongs.  We use `0' instead of `w' for this
393   field so that the field need not be specified in machine descriptions.  */
394DEF_RTL_EXPR(MEM, "mem", "e0", RTX_OBJ)
395
396/* Reference to an assembler label in the code for this function.
397   The operand is a CODE_LABEL found in the insn chain.  */
398DEF_RTL_EXPR(LABEL_REF, "label_ref", "u", RTX_CONST_OBJ)
399
400/* Reference to a named label:
401   Operand 0: label name
402   Operand 1: flags (see SYMBOL_FLAG_* in rtl.h)
403   Operand 2: tree from which this symbol is derived, or null.
404   This is either a DECL node, or some kind of constant.  */
405DEF_RTL_EXPR(SYMBOL_REF, "symbol_ref", "s00", RTX_CONST_OBJ)
406
407/* The condition code register is represented, in our imagination,
408   as a register holding a value that can be compared to zero.
409   In fact, the machine has already compared them and recorded the
410   results; but instructions that look at the condition code
411   pretend to be looking at the entire value and comparing it.  */
412DEF_RTL_EXPR(CC0, "cc0", "", RTX_OBJ)
413
414/* ----------------------------------------------------------------------
415   Expressions for operators in an rtl pattern
416   ---------------------------------------------------------------------- */
417
418/* if_then_else.  This is used in representing ordinary
419   conditional jump instructions.
420     Operand:
421     0:  condition
422     1:  then expr
423     2:  else expr */
424DEF_RTL_EXPR(IF_THEN_ELSE, "if_then_else", "eee", RTX_TERNARY)
425
426/* Comparison, produces a condition code result.  */
427DEF_RTL_EXPR(COMPARE, "compare", "ee", RTX_BIN_ARITH)
428
429/* plus */
430DEF_RTL_EXPR(PLUS, "plus", "ee", RTX_COMM_ARITH)
431
432/* Operand 0 minus operand 1.  */
433DEF_RTL_EXPR(MINUS, "minus", "ee", RTX_BIN_ARITH)
434
435/* Minus operand 0.  */
436DEF_RTL_EXPR(NEG, "neg", "e", RTX_UNARY)
437
438DEF_RTL_EXPR(MULT, "mult", "ee", RTX_COMM_ARITH)
439
440/* Operand 0 divided by operand 1.  */
441DEF_RTL_EXPR(DIV, "div", "ee", RTX_BIN_ARITH)
442/* Remainder of operand 0 divided by operand 1.  */
443DEF_RTL_EXPR(MOD, "mod", "ee", RTX_BIN_ARITH)
444
445/* Unsigned divide and remainder.  */
446DEF_RTL_EXPR(UDIV, "udiv", "ee", RTX_BIN_ARITH)
447DEF_RTL_EXPR(UMOD, "umod", "ee", RTX_BIN_ARITH)
448
449/* Bitwise operations.  */
450DEF_RTL_EXPR(AND, "and", "ee", RTX_COMM_ARITH)
451DEF_RTL_EXPR(IOR, "ior", "ee", RTX_COMM_ARITH)
452DEF_RTL_EXPR(XOR, "xor", "ee", RTX_COMM_ARITH)
453DEF_RTL_EXPR(NOT, "not", "e", RTX_UNARY)
454
455/* Operand:
456     0:  value to be shifted.
457     1:  number of bits.  */
458DEF_RTL_EXPR(ASHIFT, "ashift", "ee", RTX_BIN_ARITH) /* shift left */
459DEF_RTL_EXPR(ROTATE, "rotate", "ee", RTX_BIN_ARITH) /* rotate left */
460DEF_RTL_EXPR(ASHIFTRT, "ashiftrt", "ee", RTX_BIN_ARITH) /* arithmetic shift right */
461DEF_RTL_EXPR(LSHIFTRT, "lshiftrt", "ee", RTX_BIN_ARITH) /* logical shift right */
462DEF_RTL_EXPR(ROTATERT, "rotatert", "ee", RTX_BIN_ARITH) /* rotate right */
463
464/* Minimum and maximum values of two operands.  We need both signed and
465   unsigned forms.  (We cannot use MIN for SMIN because it conflicts
466   with a macro of the same name.)   The signed variants should be used
467   with floating point.  Further, if both operands are zeros, or if either
468   operand is NaN, then it is unspecified which of the two operands is
469   returned as the result.  */
470
471DEF_RTL_EXPR(SMIN, "smin", "ee", RTX_COMM_ARITH)
472DEF_RTL_EXPR(SMAX, "smax", "ee", RTX_COMM_ARITH)
473DEF_RTL_EXPR(UMIN, "umin", "ee", RTX_COMM_ARITH)
474DEF_RTL_EXPR(UMAX, "umax", "ee", RTX_COMM_ARITH)
475
476/* These unary operations are used to represent incrementation
477   and decrementation as they occur in memory addresses.
478   The amount of increment or decrement are not represented
479   because they can be understood from the machine-mode of the
480   containing MEM.  These operations exist in only two cases:
481   1. pushes onto the stack.
482   2. created automatically by the life_analysis pass in flow.c.  */
483DEF_RTL_EXPR(PRE_DEC, "pre_dec", "e", RTX_AUTOINC)
484DEF_RTL_EXPR(PRE_INC, "pre_inc", "e", RTX_AUTOINC)
485DEF_RTL_EXPR(POST_DEC, "post_dec", "e", RTX_AUTOINC)
486DEF_RTL_EXPR(POST_INC, "post_inc", "e", RTX_AUTOINC)
487
488/* These binary operations are used to represent generic address
489   side-effects in memory addresses, except for simple incrementation
490   or decrementation which use the above operations.  They are
491   created automatically by the life_analysis pass in flow.c.
492   The first operand is a REG which is used as the address.
493   The second operand is an expression that is assigned to the
494   register, either before (PRE_MODIFY) or after (POST_MODIFY)
495   evaluating the address.
496   Currently, the compiler can only handle second operands of the
497   form (plus (reg) (reg)) and (plus (reg) (const_int)), where
498   the first operand of the PLUS has to be the same register as
499   the first operand of the *_MODIFY.  */
500DEF_RTL_EXPR(PRE_MODIFY, "pre_modify", "ee", RTX_AUTOINC)
501DEF_RTL_EXPR(POST_MODIFY, "post_modify", "ee", RTX_AUTOINC)
502
503/* Comparison operations.  The ordered comparisons exist in two
504   flavors, signed and unsigned.  */
505DEF_RTL_EXPR(NE, "ne", "ee", RTX_COMM_COMPARE)
506DEF_RTL_EXPR(EQ, "eq", "ee", RTX_COMM_COMPARE)
507DEF_RTL_EXPR(GE, "ge", "ee", RTX_COMPARE)
508DEF_RTL_EXPR(GT, "gt", "ee", RTX_COMPARE)
509DEF_RTL_EXPR(LE, "le", "ee", RTX_COMPARE)
510DEF_RTL_EXPR(LT, "lt", "ee", RTX_COMPARE)
511DEF_RTL_EXPR(GEU, "geu", "ee", RTX_COMPARE)
512DEF_RTL_EXPR(GTU, "gtu", "ee", RTX_COMPARE)
513DEF_RTL_EXPR(LEU, "leu", "ee", RTX_COMPARE)
514DEF_RTL_EXPR(LTU, "ltu", "ee", RTX_COMPARE)
515
516/* Additional floating point unordered comparison flavors.  */
517DEF_RTL_EXPR(UNORDERED, "unordered", "ee", RTX_COMM_COMPARE)
518DEF_RTL_EXPR(ORDERED, "ordered", "ee", RTX_COMM_COMPARE)
519
520/* These are equivalent to unordered or ...  */
521DEF_RTL_EXPR(UNEQ, "uneq", "ee", RTX_COMM_COMPARE)
522DEF_RTL_EXPR(UNGE, "unge", "ee", RTX_COMPARE)
523DEF_RTL_EXPR(UNGT, "ungt", "ee", RTX_COMPARE)
524DEF_RTL_EXPR(UNLE, "unle", "ee", RTX_COMPARE)
525DEF_RTL_EXPR(UNLT, "unlt", "ee", RTX_COMPARE)
526
527/* This is an ordered NE, ie !UNEQ, ie false for NaN.  */
528DEF_RTL_EXPR(LTGT, "ltgt", "ee", RTX_COMM_COMPARE)
529
530/* Represents the result of sign-extending the sole operand.
531   The machine modes of the operand and of the SIGN_EXTEND expression
532   determine how much sign-extension is going on.  */
533DEF_RTL_EXPR(SIGN_EXTEND, "sign_extend", "e", RTX_UNARY)
534
535/* Similar for zero-extension (such as unsigned short to int).  */
536DEF_RTL_EXPR(ZERO_EXTEND, "zero_extend", "e", RTX_UNARY)
537
538/* Similar but here the operand has a wider mode.  */
539DEF_RTL_EXPR(TRUNCATE, "truncate", "e", RTX_UNARY)
540
541/* Similar for extending floating-point values (such as SFmode to DFmode).  */
542DEF_RTL_EXPR(FLOAT_EXTEND, "float_extend", "e", RTX_UNARY)
543DEF_RTL_EXPR(FLOAT_TRUNCATE, "float_truncate", "e", RTX_UNARY)
544
545/* Conversion of fixed point operand to floating point value.  */
546DEF_RTL_EXPR(FLOAT, "float", "e", RTX_UNARY)
547
548/* With fixed-point machine mode:
549   Conversion of floating point operand to fixed point value.
550   Value is defined only when the operand's value is an integer.
551   With floating-point machine mode (and operand with same mode):
552   Operand is rounded toward zero to produce an integer value
553   represented in floating point.  */
554DEF_RTL_EXPR(FIX, "fix", "e", RTX_UNARY)
555
556/* Conversion of unsigned fixed point operand to floating point value.  */
557DEF_RTL_EXPR(UNSIGNED_FLOAT, "unsigned_float", "e", RTX_UNARY)
558
559/* With fixed-point machine mode:
560   Conversion of floating point operand to *unsigned* fixed point value.
561   Value is defined only when the operand's value is an integer.  */
562DEF_RTL_EXPR(UNSIGNED_FIX, "unsigned_fix", "e", RTX_UNARY)
563
564/* Absolute value */
565DEF_RTL_EXPR(ABS, "abs", "e", RTX_UNARY)
566
567/* Square root */
568DEF_RTL_EXPR(SQRT, "sqrt", "e", RTX_UNARY)
569
570/* Find first bit that is set.
571   Value is 1 + number of trailing zeros in the arg.,
572   or 0 if arg is 0.  */
573DEF_RTL_EXPR(FFS, "ffs", "e", RTX_UNARY)
574
575/* Count leading zeros.  */
576DEF_RTL_EXPR(CLZ, "clz", "e", RTX_UNARY)
577
578/* Count trailing zeros.  */
579DEF_RTL_EXPR(CTZ, "ctz", "e", RTX_UNARY)
580
581/* Population count (number of 1 bits).  */
582DEF_RTL_EXPR(POPCOUNT, "popcount", "e", RTX_UNARY)
583
584/* Population parity (number of 1 bits modulo 2).  */
585DEF_RTL_EXPR(PARITY, "parity", "e", RTX_UNARY)
586
587/* Reference to a signed bit-field of specified size and position.
588   Operand 0 is the memory unit (usually SImode or QImode) which
589   contains the field's first bit.  Operand 1 is the width, in bits.
590   Operand 2 is the number of bits in the memory unit before the
591   first bit of this field.
592   If BITS_BIG_ENDIAN is defined, the first bit is the msb and
593   operand 2 counts from the msb of the memory unit.
594   Otherwise, the first bit is the lsb and operand 2 counts from
595   the lsb of the memory unit.
596   This kind of expression can not appear as an lvalue in RTL.  */
597DEF_RTL_EXPR(SIGN_EXTRACT, "sign_extract", "eee", RTX_BITFIELD_OPS)
598
599/* Similar for unsigned bit-field.
600   But note!  This kind of expression _can_ appear as an lvalue.  */
601DEF_RTL_EXPR(ZERO_EXTRACT, "zero_extract", "eee", RTX_BITFIELD_OPS)
602
603/* For RISC machines.  These save memory when splitting insns.  */
604
605/* HIGH are the high-order bits of a constant expression.  */
606DEF_RTL_EXPR(HIGH, "high", "e", RTX_CONST_OBJ)
607
608/* LO_SUM is the sum of a register and the low-order bits
609   of a constant expression.  */
610DEF_RTL_EXPR(LO_SUM, "lo_sum", "ee", RTX_OBJ)
611
612/* Describes a merge operation between two vector values.
613   Operands 0 and 1 are the vectors to be merged, operand 2 is a bitmask
614   that specifies where the parts of the result are taken from.  Set bits
615   indicate operand 0, clear bits indicate operand 1.  The parts are defined
616   by the mode of the vectors.  */
617DEF_RTL_EXPR(VEC_MERGE, "vec_merge", "eee", RTX_TERNARY)
618
619/* Describes an operation that selects parts of a vector.
620   Operands 0 is the source vector, operand 1 is a PARALLEL that contains
621   a CONST_INT for each of the subparts of the result vector, giving the
622   number of the source subpart that should be stored into it.  */
623DEF_RTL_EXPR(VEC_SELECT, "vec_select", "ee", RTX_BIN_ARITH)
624
625/* Describes a vector concat operation.  Operands 0 and 1 are the source
626   vectors, the result is a vector that is as long as operands 0 and 1
627   combined and is the concatenation of the two source vectors.  */
628DEF_RTL_EXPR(VEC_CONCAT, "vec_concat", "ee", RTX_BIN_ARITH)
629
630/* Describes an operation that converts a small vector into a larger one by
631   duplicating the input values.  The output vector mode must have the same
632   submodes as the input vector mode, and the number of output parts must be
633   an integer multiple of the number of input parts.  */
634DEF_RTL_EXPR(VEC_DUPLICATE, "vec_duplicate", "e", RTX_UNARY)
635
636/* Addition with signed saturation */
637DEF_RTL_EXPR(SS_PLUS, "ss_plus", "ee", RTX_COMM_ARITH)
638
639/* Addition with unsigned saturation */
640DEF_RTL_EXPR(US_PLUS, "us_plus", "ee", RTX_COMM_ARITH)
641
642/* Operand 0 minus operand 1, with signed saturation.  */
643DEF_RTL_EXPR(SS_MINUS, "ss_minus", "ee", RTX_BIN_ARITH)
644
645/* Negation with signed saturation.  */
646DEF_RTL_EXPR(SS_NEG, "ss_neg", "e", RTX_UNARY)
647
648/* Shift left with signed saturation.  */
649DEF_RTL_EXPR(SS_ASHIFT, "ss_ashift", "ee", RTX_BIN_ARITH)
650
651/* Operand 0 minus operand 1, with unsigned saturation.  */
652DEF_RTL_EXPR(US_MINUS, "us_minus", "ee", RTX_BIN_ARITH)
653
654/* Signed saturating truncate.  */
655DEF_RTL_EXPR(SS_TRUNCATE, "ss_truncate", "e", RTX_UNARY)
656
657/* Unsigned saturating truncate.  */
658DEF_RTL_EXPR(US_TRUNCATE, "us_truncate", "e", RTX_UNARY)
659
660/* Information about the variable and its location.  */
661DEF_RTL_EXPR(VAR_LOCATION, "var_location", "te", RTX_EXTRA)
662
663/* All expressions from this point forward appear only in machine
664   descriptions.  */
665#ifdef GENERATOR_FILE
666
667/* Include a secondary machine-description file at this point.  */
668DEF_RTL_EXPR(INCLUDE, "include", "s", RTX_EXTRA)
669
670/* Pattern-matching operators:  */
671
672/* Use the function named by the second arg (the string)
673   as a predicate; if matched, store the structure that was matched
674   in the operand table at index specified by the first arg (the integer).
675   If the second arg is the null string, the structure is just stored.
676
677   A third string argument indicates to the register allocator restrictions
678   on where the operand can be allocated.
679
680   If the target needs no restriction on any instruction this field should
681   be the null string.
682
683   The string is prepended by:
684   '=' to indicate the operand is only written to.
685   '+' to indicate the operand is both read and written to.
686
687   Each character in the string represents an allocable class for an operand.
688   'g' indicates the operand can be any valid class.
689   'i' indicates the operand can be immediate (in the instruction) data.
690   'r' indicates the operand can be in a register.
691   'm' indicates the operand can be in memory.
692   'o' a subset of the 'm' class.  Those memory addressing modes that
693       can be offset at compile time (have a constant added to them).
694
695   Other characters indicate target dependent operand classes and
696   are described in each target's machine description.
697
698   For instructions with more than one operand, sets of classes can be
699   separated by a comma to indicate the appropriate multi-operand constraints.
700   There must be a 1 to 1 correspondence between these sets of classes in
701   all operands for an instruction.
702   */
703DEF_RTL_EXPR(MATCH_OPERAND, "match_operand", "iss", RTX_MATCH)
704
705/* Match a SCRATCH or a register.  When used to generate rtl, a
706   SCRATCH is generated.  As for MATCH_OPERAND, the mode specifies
707   the desired mode and the first argument is the operand number.
708   The second argument is the constraint.  */
709DEF_RTL_EXPR(MATCH_SCRATCH, "match_scratch", "is", RTX_MATCH)
710
711/* Apply a predicate, AND match recursively the operands of the rtx.
712   Operand 0 is the operand-number, as in match_operand.
713   Operand 1 is a predicate to apply (as a string, a function name).
714   Operand 2 is a vector of expressions, each of which must match
715   one subexpression of the rtx this construct is matching.  */
716DEF_RTL_EXPR(MATCH_OPERATOR, "match_operator", "isE", RTX_MATCH)
717
718/* Match a PARALLEL of arbitrary length.  The predicate is applied
719   to the PARALLEL and the initial expressions in the PARALLEL are matched.
720   Operand 0 is the operand-number, as in match_operand.
721   Operand 1 is a predicate to apply to the PARALLEL.
722   Operand 2 is a vector of expressions, each of which must match the
723   corresponding element in the PARALLEL.  */
724DEF_RTL_EXPR(MATCH_PARALLEL, "match_parallel", "isE", RTX_MATCH)
725
726/* Match only something equal to what is stored in the operand table
727   at the index specified by the argument.  Use with MATCH_OPERAND.  */
728DEF_RTL_EXPR(MATCH_DUP, "match_dup", "i", RTX_MATCH)
729
730/* Match only something equal to what is stored in the operand table
731   at the index specified by the argument.  Use with MATCH_OPERATOR.  */
732DEF_RTL_EXPR(MATCH_OP_DUP, "match_op_dup", "iE", RTX_MATCH)
733
734/* Match only something equal to what is stored in the operand table
735   at the index specified by the argument.  Use with MATCH_PARALLEL.  */
736DEF_RTL_EXPR(MATCH_PAR_DUP, "match_par_dup", "iE", RTX_MATCH)
737
738/* Appears only in define_predicate/define_special_predicate
739   expressions.  Evaluates true only if the operand has an RTX code
740   from the set given by the argument (a comma-separated list).  If the
741   second argument is present and nonempty, it is a sequence of digits
742   and/or letters which indicates the subexpression to test, using the
743   same syntax as genextract/genrecog's location strings: 0-9 for
744   XEXP (op, n), a-z for XVECEXP (op, 0, n); each character applies to
745   the result of the one before it.  */
746DEF_RTL_EXPR(MATCH_CODE, "match_code", "ss", RTX_MATCH)
747
748/* Appears only in define_predicate/define_special_predicate
749    expressions.  The argument is a C expression to be injected at this
750    point in the predicate formula.  */
751DEF_RTL_EXPR(MATCH_TEST, "match_test", "s", RTX_MATCH)
752
753/* Insn (and related) definitions.  */
754
755/* Definition of the pattern for one kind of instruction.
756   Operand:
757   0: names this instruction.
758      If the name is the null string, the instruction is in the
759      machine description just to be recognized, and will never be emitted by
760      the tree to rtl expander.
761   1: is the pattern.
762   2: is a string which is a C expression
763      giving an additional condition for recognizing this pattern.
764      A null string means no extra condition.
765   3: is the action to execute if this pattern is matched.
766      If this assembler code template starts with a * then it is a fragment of
767      C code to run to decide on a template to use.  Otherwise, it is the
768      template to use.
769   4: optionally, a vector of attributes for this insn.
770     */
771DEF_RTL_EXPR(DEFINE_INSN, "define_insn", "sEsTV", RTX_EXTRA)
772
773/* Definition of a peephole optimization.
774   1st operand: vector of insn patterns to match
775   2nd operand: C expression that must be true
776   3rd operand: template or C code to produce assembler output.
777   4: optionally, a vector of attributes for this insn.
778
779   This form is deprecated; use define_peephole2 instead.  */
780DEF_RTL_EXPR(DEFINE_PEEPHOLE, "define_peephole", "EsTV", RTX_EXTRA)
781
782/* Definition of a split operation.
783   1st operand: insn pattern to match
784   2nd operand: C expression that must be true
785   3rd operand: vector of insn patterns to place into a SEQUENCE
786   4th operand: optionally, some C code to execute before generating the
787	insns.  This might, for example, create some RTX's and store them in
788	elements of `recog_data.operand' for use by the vector of
789	insn-patterns.
790	(`operands' is an alias here for `recog_data.operand').  */
791DEF_RTL_EXPR(DEFINE_SPLIT, "define_split", "EsES", RTX_EXTRA)
792
793/* Definition of an insn and associated split.
794   This is the concatenation, with a few modifications, of a define_insn
795   and a define_split which share the same pattern.
796   Operand:
797   0: names this instruction.
798      If the name is the null string, the instruction is in the
799      machine description just to be recognized, and will never be emitted by
800      the tree to rtl expander.
801   1: is the pattern.
802   2: is a string which is a C expression
803      giving an additional condition for recognizing this pattern.
804      A null string means no extra condition.
805   3: is the action to execute if this pattern is matched.
806      If this assembler code template starts with a * then it is a fragment of
807      C code to run to decide on a template to use.  Otherwise, it is the
808      template to use.
809   4: C expression that must be true for split.  This may start with "&&"
810      in which case the split condition is the logical and of the insn
811      condition and what follows the "&&" of this operand.
812   5: vector of insn patterns to place into a SEQUENCE
813   6: optionally, some C code to execute before generating the
814	insns.  This might, for example, create some RTX's and store them in
815	elements of `recog_data.operand' for use by the vector of
816	insn-patterns.
817	(`operands' is an alias here for `recog_data.operand').
818   7: optionally, a vector of attributes for this insn.  */
819DEF_RTL_EXPR(DEFINE_INSN_AND_SPLIT, "define_insn_and_split", "sEsTsESV", RTX_EXTRA)
820
821/* Definition of an RTL peephole operation.
822   Follows the same arguments as define_split.  */
823DEF_RTL_EXPR(DEFINE_PEEPHOLE2, "define_peephole2", "EsES", RTX_EXTRA)
824
825/* Define how to generate multiple insns for a standard insn name.
826   1st operand: the insn name.
827   2nd operand: vector of insn-patterns.
828	Use match_operand to substitute an element of `recog_data.operand'.
829   3rd operand: C expression that must be true for this to be available.
830	This may not test any operands.
831   4th operand: Extra C code to execute before generating the insns.
832	This might, for example, create some RTX's and store them in
833	elements of `recog_data.operand' for use by the vector of
834	insn-patterns.
835	(`operands' is an alias here for `recog_data.operand').  */
836DEF_RTL_EXPR(DEFINE_EXPAND, "define_expand", "sEss", RTX_EXTRA)
837
838/* Define a requirement for delay slots.
839   1st operand: Condition involving insn attributes that, if true,
840	        indicates that the insn requires the number of delay slots
841		shown.
842   2nd operand: Vector whose length is the three times the number of delay
843		slots required.
844	        Each entry gives three conditions, each involving attributes.
845		The first must be true for an insn to occupy that delay slot
846		location.  The second is true for all insns that can be
847		annulled if the branch is true and the third is true for all
848		insns that can be annulled if the branch is false.
849
850   Multiple DEFINE_DELAYs may be present.  They indicate differing
851   requirements for delay slots.  */
852DEF_RTL_EXPR(DEFINE_DELAY, "define_delay", "eE", RTX_EXTRA)
853
854/* Define attribute computation for `asm' instructions.  */
855DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES, "define_asm_attributes", "V", RTX_EXTRA)
856
857/* Definition of a conditional execution meta operation.  Automatically
858   generates new instances of DEFINE_INSN, selected by having attribute
859   "predicable" true.  The new pattern will contain a COND_EXEC and the
860   predicate at top-level.
861
862   Operand:
863   0: The predicate pattern.  The top-level form should match a
864      relational operator.  Operands should have only one alternative.
865   1: A C expression giving an additional condition for recognizing
866      the generated pattern.
867   2: A template or C code to produce assembler output.  */
868DEF_RTL_EXPR(DEFINE_COND_EXEC, "define_cond_exec", "Ess", RTX_EXTRA)
869
870/* Definition of an operand predicate.  The difference between
871   DEFINE_PREDICATE and DEFINE_SPECIAL_PREDICATE is that genrecog will
872   not warn about a match_operand with no mode if it has a predicate
873   defined with DEFINE_SPECIAL_PREDICATE.
874
875   Operand:
876   0: The name of the predicate.
877   1: A boolean expression which computes whether or not the predicate
878      matches.  This expression can use IOR, AND, NOT, MATCH_OPERAND,
879      MATCH_CODE, and MATCH_TEST.  It must be specific enough that genrecog
880      can calculate the set of RTX codes that can possibly match.
881   2: A C function body which must return true for the predicate to match.
882      Optional.  Use this when the test is too complicated to fit into a
883      match_test expression.  */
884DEF_RTL_EXPR(DEFINE_PREDICATE, "define_predicate", "ses", RTX_EXTRA)
885DEF_RTL_EXPR(DEFINE_SPECIAL_PREDICATE, "define_special_predicate", "ses", RTX_EXTRA)
886
887/* Definition of a register operand constraint.  This simply maps the
888   constraint string to a register class.
889
890   Operand:
891   0: The name of the constraint (often, but not always, a single letter).
892   1: A C expression which evaluates to the appropriate register class for
893      this constraint.  If this is not just a constant, it should look only
894      at -m switches and the like.
895   2: A docstring for this constraint, in Texinfo syntax; not currently
896      used, in future will be incorporated into the manual's list of
897      machine-specific operand constraints.  */
898DEF_RTL_EXPR(DEFINE_REGISTER_CONSTRAINT, "define_register_constraint", "sss", RTX_EXTRA)
899
900/* Definition of a non-register operand constraint.  These look at the
901   operand and decide whether it fits the constraint.
902
903   DEFINE_CONSTRAINT gets no special treatment if it fails to match.
904   It is appropriate for constant-only constraints, and most others.
905
906   DEFINE_MEMORY_CONSTRAINT tells reload that this constraint can be made
907   to match, if it doesn't already, by converting the operand to the form
908   (mem (reg X)) where X is a base register.  It is suitable for constraints
909   that describe a subset of all memory references.
910
911   DEFINE_ADDRESS_CONSTRAINT tells reload that this constraint can be made
912   to match, if it doesn't already, by converting the operand to the form
913   (reg X) where X is a base register.  It is suitable for constraints that
914   describe a subset of all address references.
915
916   When in doubt, use plain DEFINE_CONSTRAINT.
917
918   Operand:
919   0: The name of the constraint (often, but not always, a single letter).
920   1: A docstring for this constraint, in Texinfo syntax; not currently
921      used, in future will be incorporated into the manual's list of
922      machine-specific operand constraints.
923   2: A boolean expression which computes whether or not the constraint
924      matches.  It should follow the same rules as a define_predicate
925      expression, including the bit about specifying the set of RTX codes
926      that could possibly match.  MATCH_TEST subexpressions may make use of
927      these variables:
928        `op'    - the RTL object defining the operand.
929        `mode'  - the mode of `op'.
930	`ival'  - INTVAL(op), if op is a CONST_INT.
931        `hval'  - CONST_DOUBLE_HIGH(op), if op is an integer CONST_DOUBLE.
932        `lval'  - CONST_DOUBLE_LOW(op), if op is an integer CONST_DOUBLE.
933        `rval'  - CONST_DOUBLE_REAL_VALUE(op), if op is a floating-point
934                  CONST_DOUBLE.
935      Do not use ival/hval/lval/rval if op is not the appropriate kind of
936      RTL object.  */
937DEF_RTL_EXPR(DEFINE_CONSTRAINT, "define_constraint", "sse", RTX_EXTRA)
938DEF_RTL_EXPR(DEFINE_MEMORY_CONSTRAINT, "define_memory_constraint", "sse", RTX_EXTRA)
939DEF_RTL_EXPR(DEFINE_ADDRESS_CONSTRAINT, "define_address_constraint", "sse", RTX_EXTRA)
940
941
942/* Constructions for CPU pipeline description described by NDFAs.  */
943
944/* (define_cpu_unit string [string]) describes cpu functional
945   units (separated by comma).
946
947   1st operand: Names of cpu functional units.
948   2nd operand: Name of automaton (see comments for DEFINE_AUTOMATON).
949
950   All define_reservations, define_cpu_units, and
951   define_query_cpu_units should have unique names which may not be
952   "nothing".  */
953DEF_RTL_EXPR(DEFINE_CPU_UNIT, "define_cpu_unit", "sS", RTX_EXTRA)
954
955/* (define_query_cpu_unit string [string]) describes cpu functional
956   units analogously to define_cpu_unit.  The reservation of such
957   units can be queried for automaton state.  */
958DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT, "define_query_cpu_unit", "sS", RTX_EXTRA)
959
960/* (exclusion_set string string) means that each CPU functional unit
961   in the first string can not be reserved simultaneously with any
962   unit whose name is in the second string and vise versa.  CPU units
963   in the string are separated by commas.  For example, it is useful
964   for description CPU with fully pipelined floating point functional
965   unit which can execute simultaneously only single floating point
966   insns or only double floating point insns.  All CPU functional
967   units in a set should belong to the same automaton.  */
968DEF_RTL_EXPR(EXCLUSION_SET, "exclusion_set", "ss", RTX_EXTRA)
969
970/* (presence_set string string) means that each CPU functional unit in
971   the first string can not be reserved unless at least one of pattern
972   of units whose names are in the second string is reserved.  This is
973   an asymmetric relation.  CPU units or unit patterns in the strings
974   are separated by commas.  Pattern is one unit name or unit names
975   separated by white-spaces.
976
977   For example, it is useful for description that slot1 is reserved
978   after slot0 reservation for a VLIW processor.  We could describe it
979   by the following construction
980
981      (presence_set "slot1" "slot0")
982
983   Or slot1 is reserved only after slot0 and unit b0 reservation.  In
984   this case we could write
985
986      (presence_set "slot1" "slot0 b0")
987
988   All CPU functional units in a set should belong to the same
989   automaton.  */
990DEF_RTL_EXPR(PRESENCE_SET, "presence_set", "ss", RTX_EXTRA)
991
992/* (final_presence_set string string) is analogous to `presence_set'.
993   The difference between them is when checking is done.  When an
994   instruction is issued in given automaton state reflecting all
995   current and planned unit reservations, the automaton state is
996   changed.  The first state is a source state, the second one is a
997   result state.  Checking for `presence_set' is done on the source
998   state reservation, checking for `final_presence_set' is done on the
999   result reservation.  This construction is useful to describe a
1000   reservation which is actually two subsequent reservations.  For
1001   example, if we use
1002
1003      (presence_set "slot1" "slot0")
1004
1005   the following insn will be never issued (because slot1 requires
1006   slot0 which is absent in the source state).
1007
1008      (define_reservation "insn_and_nop" "slot0 + slot1")
1009
1010   but it can be issued if we use analogous `final_presence_set'.  */
1011DEF_RTL_EXPR(FINAL_PRESENCE_SET, "final_presence_set", "ss", RTX_EXTRA)
1012
1013/* (absence_set string string) means that each CPU functional unit in
1014   the first string can be reserved only if each pattern of units
1015   whose names are in the second string is not reserved.  This is an
1016   asymmetric relation (actually exclusion set is analogous to this
1017   one but it is symmetric).  CPU units or unit patterns in the string
1018   are separated by commas.  Pattern is one unit name or unit names
1019   separated by white-spaces.
1020
1021   For example, it is useful for description that slot0 can not be
1022   reserved after slot1 or slot2 reservation for a VLIW processor.  We
1023   could describe it by the following construction
1024
1025      (absence_set "slot2" "slot0, slot1")
1026
1027   Or slot2 can not be reserved if slot0 and unit b0 are reserved or
1028   slot1 and unit b1 are reserved .  In this case we could write
1029
1030      (absence_set "slot2" "slot0 b0, slot1 b1")
1031
1032   All CPU functional units in a set should to belong the same
1033   automaton.  */
1034DEF_RTL_EXPR(ABSENCE_SET, "absence_set", "ss", RTX_EXTRA)
1035
1036/* (final_absence_set string string) is analogous to `absence_set' but
1037   checking is done on the result (state) reservation.  See comments
1038   for `final_presence_set'.  */
1039DEF_RTL_EXPR(FINAL_ABSENCE_SET, "final_absence_set", "ss", RTX_EXTRA)
1040
1041/* (define_bypass number out_insn_names in_insn_names) names bypass
1042   with given latency (the first number) from insns given by the first
1043   string (see define_insn_reservation) into insns given by the second
1044   string.  Insn names in the strings are separated by commas.  The
1045   third operand is optional name of function which is additional
1046   guard for the bypass.  The function will get the two insns as
1047   parameters.  If the function returns zero the bypass will be
1048   ignored for this case.  Additional guard is necessary to recognize
1049   complicated bypasses, e.g. when consumer is load address.  */
1050DEF_RTL_EXPR(DEFINE_BYPASS, "define_bypass", "issS", RTX_EXTRA)
1051
1052/* (define_automaton string) describes names of automata generated and
1053   used for pipeline hazards recognition.  The names are separated by
1054   comma.  Actually it is possibly to generate the single automaton
1055   but unfortunately it can be very large.  If we use more one
1056   automata, the summary size of the automata usually is less than the
1057   single one.  The automaton name is used in define_cpu_unit and
1058   define_query_cpu_unit.  All automata should have unique names.  */
1059DEF_RTL_EXPR(DEFINE_AUTOMATON, "define_automaton", "s", RTX_EXTRA)
1060
1061/* (automata_option string) describes option for generation of
1062   automata.  Currently there are the following options:
1063
1064   o "no-minimization" which makes no minimization of automata.  This
1065     is only worth to do when we are debugging the description and
1066     need to look more accurately at reservations of states.
1067
1068   o "time" which means printing additional time statistics about
1069      generation of automata.
1070
1071   o "v" which means generation of file describing the result
1072     automata.  The file has suffix `.dfa' and can be used for the
1073     description verification and debugging.
1074
1075   o "w" which means generation of warning instead of error for
1076     non-critical errors.
1077
1078   o "ndfa" which makes nondeterministic finite state automata.
1079
1080   o "progress" which means output of a progress bar showing how many
1081     states were generated so far for automaton being processed.  */
1082DEF_RTL_EXPR(AUTOMATA_OPTION, "automata_option", "s", RTX_EXTRA)
1083
1084/* (define_reservation string string) names reservation (the first
1085   string) of cpu functional units (the 2nd string).  Sometimes unit
1086   reservations for different insns contain common parts.  In such
1087   case, you can describe common part and use its name (the 1st
1088   parameter) in regular expression in define_insn_reservation.  All
1089   define_reservations, define_cpu_units, and define_query_cpu_units
1090   should have unique names which may not be "nothing".  */
1091DEF_RTL_EXPR(DEFINE_RESERVATION, "define_reservation", "ss", RTX_EXTRA)
1092
1093/* (define_insn_reservation name default_latency condition regexpr)
1094   describes reservation of cpu functional units (the 3nd operand) for
1095   instruction which is selected by the condition (the 2nd parameter).
1096   The first parameter is used for output of debugging information.
1097   The reservations are described by a regular expression according
1098   the following syntax:
1099
1100       regexp = regexp "," oneof
1101              | oneof
1102
1103       oneof = oneof "|" allof
1104             | allof
1105
1106       allof = allof "+" repeat
1107             | repeat
1108
1109       repeat = element "*" number
1110              | element
1111
1112       element = cpu_function_unit_name
1113               | reservation_name
1114               | result_name
1115               | "nothing"
1116               | "(" regexp ")"
1117
1118       1. "," is used for describing start of the next cycle in
1119       reservation.
1120
1121       2. "|" is used for describing the reservation described by the
1122       first regular expression *or* the reservation described by the
1123       second regular expression *or* etc.
1124
1125       3. "+" is used for describing the reservation described by the
1126       first regular expression *and* the reservation described by the
1127       second regular expression *and* etc.
1128
1129       4. "*" is used for convenience and simply means sequence in
1130       which the regular expression are repeated NUMBER times with
1131       cycle advancing (see ",").
1132
1133       5. cpu functional unit name which means its reservation.
1134
1135       6. reservation name -- see define_reservation.
1136
1137       7. string "nothing" means no units reservation.  */
1138
1139DEF_RTL_EXPR(DEFINE_INSN_RESERVATION, "define_insn_reservation", "sies", RTX_EXTRA)
1140
1141/* Expressions used for insn attributes.  */
1142
1143/* Definition of an insn attribute.
1144   1st operand: name of the attribute
1145   2nd operand: comma-separated list of possible attribute values
1146   3rd operand: expression for the default value of the attribute.  */
1147DEF_RTL_EXPR(DEFINE_ATTR, "define_attr", "sse", RTX_EXTRA)
1148
1149/* Marker for the name of an attribute.  */
1150DEF_RTL_EXPR(ATTR, "attr", "s", RTX_EXTRA)
1151
1152/* For use in the last (optional) operand of DEFINE_INSN or DEFINE_PEEPHOLE and
1153   in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that
1154   pattern.
1155
1156   (set_attr "name" "value") is equivalent to
1157   (set (attr "name") (const_string "value"))  */
1158DEF_RTL_EXPR(SET_ATTR, "set_attr", "ss", RTX_EXTRA)
1159
1160/* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE, this can be used to
1161   specify that attribute values are to be assigned according to the
1162   alternative matched.
1163
1164   The following three expressions are equivalent:
1165
1166   (set (attr "att") (cond [(eq_attrq "alternative" "1") (const_string "a1")
1167			    (eq_attrq "alternative" "2") (const_string "a2")]
1168			   (const_string "a3")))
1169   (set_attr_alternative "att" [(const_string "a1") (const_string "a2")
1170				 (const_string "a3")])
1171   (set_attr "att" "a1,a2,a3")
1172 */
1173DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE, "set_attr_alternative", "sE", RTX_EXTRA)
1174
1175/* A conditional expression true if the value of the specified attribute of
1176   the current insn equals the specified value.  The first operand is the
1177   attribute name and the second is the comparison value.  */
1178DEF_RTL_EXPR(EQ_ATTR, "eq_attr", "ss", RTX_EXTRA)
1179
1180/* A special case of the above representing a set of alternatives.  The first
1181   operand is bitmap of the set, the second one is the default value.  */
1182DEF_RTL_EXPR(EQ_ATTR_ALT, "eq_attr_alt", "ii", RTX_EXTRA)
1183
1184/* A conditional expression which is true if the specified flag is
1185   true for the insn being scheduled in reorg.
1186
1187   genattr.c defines the following flags which can be tested by
1188   (attr_flag "foo") expressions in eligible_for_delay.
1189
1190   forward, backward, very_likely, likely, very_unlikely, and unlikely.  */
1191
1192DEF_RTL_EXPR (ATTR_FLAG, "attr_flag", "s", RTX_EXTRA)
1193
1194/* General conditional. The first operand is a vector composed of pairs of
1195   expressions.  The first element of each pair is evaluated, in turn.
1196   The value of the conditional is the second expression of the first pair
1197   whose first expression evaluates nonzero.  If none of the expressions is
1198   true, the second operand will be used as the value of the conditional.  */
1199DEF_RTL_EXPR(COND, "cond", "Ee", RTX_EXTRA)
1200
1201#endif /* GENERATOR_FILE */
1202
1203/*
1204Local variables:
1205mode:c
1206End:
1207*/
1208