1/* This file contains the definitions and documentation for the
2   Register Transfer Expressions (rtx's) that make up the
3   Register Transfer Language (rtl) used in the Back End of the GNU compiler.
4   Copyright (C) 1987, 1988, 1992, 1994, 1995, 1997, 1998, 1999, 2000, 2004,
5   2005
6   Free Software Foundation, Inc.
7
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/* SEQUENCE appears in the result of a `gen_...' function
97   for a DEFINE_EXPAND that wants to make several insns.
98   Its elements are the bodies of the insns that should be made.
99   `emit_insn' takes the SEQUENCE apart and makes separate insns.  */
100DEF_RTL_EXPR(SEQUENCE, "sequence", "E", RTX_EXTRA)
101
102/* Refers to the address of its argument.  This is only used in alias.c.  */
103DEF_RTL_EXPR(ADDRESS, "address", "e", RTX_MATCH)
104
105/* ----------------------------------------------------------------------
106   Expression types used for things in the instruction chain.
107
108   All formats must start with "iuu" to handle the chain.
109   Each insn expression holds an rtl instruction and its semantics
110   during back-end processing.
111   See macros's in "rtl.h" for the meaning of each rtx->u.fld[].
112
113   ---------------------------------------------------------------------- */
114
115/* An instruction that cannot jump.  */
116DEF_RTL_EXPR(INSN, "insn", "iuuBieiee", RTX_INSN)
117
118/* An instruction that can possibly jump.
119   Fields ( rtx->u.fld[] ) have exact same meaning as INSN's.  */
120DEF_RTL_EXPR(JUMP_INSN, "jump_insn", "iuuBieiee0", RTX_INSN)
121
122/* An instruction that can possibly call a subroutine
123   but which will not change which instruction comes next
124   in the current function.
125   Field ( rtx->u.fld[9] ) is CALL_INSN_FUNCTION_USAGE.
126   All other fields ( rtx->u.fld[] ) have exact same meaning as INSN's.  */
127DEF_RTL_EXPR(CALL_INSN, "call_insn", "iuuBieieee", RTX_INSN)
128
129/* A marker that indicates that control will not flow through.  */
130DEF_RTL_EXPR(BARRIER, "barrier", "iuu000000", RTX_EXTRA)
131
132/* Holds a label that is followed by instructions.
133   Operand:
134   4: is used in jump.c for the use-count of the label.
135   5: is used in flow.c to point to the chain of label_ref's to this label.
136   6: is a number that is unique in the entire compilation.
137   7: is the user-given name of the label, if any.  */
138DEF_RTL_EXPR(CODE_LABEL, "code_label", "iuuB00is", RTX_EXTRA)
139
140#ifdef USE_MAPPED_LOCATION
141/* Say where in the code a source line starts, for symbol table's sake.
142   Operand:
143   4: unused if line number > 0, note-specific data otherwise.
144   5: line number if > 0, enum note_insn otherwise.
145   6: CODE_LABEL_NUMBER if line number == NOTE_INSN_DELETED_LABEL.  */
146#else
147/* Say where in the code a source line starts, for symbol table's sake.
148   Operand:
149   4: filename, if line number > 0, note-specific data otherwise.
150   5: line number if > 0, enum note_insn otherwise.
151   6: unique number if line number == note_insn_deleted_label.  */
152#endif
153DEF_RTL_EXPR(NOTE, "note", "iuuB0ni", RTX_EXTRA)
154
155/* ----------------------------------------------------------------------
156   Top level constituents of INSN, JUMP_INSN and CALL_INSN.
157   ---------------------------------------------------------------------- */
158   
159/* Conditionally execute code.
160   Operand 0 is the condition that if true, the code is executed.
161   Operand 1 is the code to be executed (typically a SET). 
162
163   Semantics are that there are no side effects if the condition
164   is false.  This pattern is created automatically by the if_convert
165   pass run after reload or by target-specific splitters.  */
166DEF_RTL_EXPR(COND_EXEC, "cond_exec", "ee", RTX_EXTRA)
167
168/* Several operations to be done in parallel (perhaps under COND_EXEC).  */
169DEF_RTL_EXPR(PARALLEL, "parallel", "E", RTX_EXTRA)
170
171/* A string that is passed through to the assembler as input.
172     One can obviously pass comments through by using the
173     assembler comment syntax.
174     These occur in an insn all by themselves as the PATTERN.
175     They also appear inside an ASM_OPERANDS
176     as a convenient way to hold a string.  */
177DEF_RTL_EXPR(ASM_INPUT, "asm_input", "s", RTX_EXTRA)
178
179#ifdef USE_MAPPED_LOCATION
180/* An assembler instruction with operands.
181   1st operand is the instruction template.
182   2nd operand is the constraint for the output.
183   3rd operand is the number of the output this expression refers to.
184     When an insn stores more than one value, a separate ASM_OPERANDS
185     is made for each output; this integer distinguishes them.
186   4th is a vector of values of input operands.
187   5th is a vector of modes and constraints for the input operands.
188     Each element is an ASM_INPUT containing a constraint string
189     and whose mode indicates the mode of the input operand.
190   6th is the source line number.  */
191DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEi", RTX_EXTRA)
192#else
193/* An assembler instruction with operands.
194   1st operand is the instruction template.
195   2nd operand is the constraint for the output.
196   3rd operand is the number of the output this expression refers to.
197     When an insn stores more than one value, a separate ASM_OPERANDS
198     is made for each output; this integer distinguishes them.
199   4th is a vector of values of input operands.
200   5th is a vector of modes and constraints for the input operands.
201     Each element is an ASM_INPUT containing a constraint string
202     and whose mode indicates the mode of the input operand.
203   6th is the name of the containing source file.
204   7th is the source line number.  */
205DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEsi", RTX_EXTRA)
206#endif
207
208/* A machine-specific operation.
209   1st operand is a vector of operands being used by the operation so that
210     any needed reloads can be done.
211   2nd operand is a unique value saying which of a number of machine-specific
212     operations is to be performed.
213   (Note that the vector must be the first operand because of the way that
214   genrecog.c record positions within an insn.)
215   This can occur all by itself in a PATTERN, as a component of a PARALLEL,
216   or inside an expression.  */
217DEF_RTL_EXPR(UNSPEC, "unspec", "Ei", RTX_EXTRA)
218
219/* Similar, but a volatile operation and one which may trap.  */
220DEF_RTL_EXPR(UNSPEC_VOLATILE, "unspec_volatile", "Ei", RTX_EXTRA)
221
222/* Vector of addresses, stored as full words.  */
223/* Each element is a LABEL_REF to a CODE_LABEL whose address we want.  */
224DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", RTX_EXTRA)
225
226/* Vector of address differences X0 - BASE, X1 - BASE, ...
227   First operand is BASE; the vector contains the X's.
228   The machine mode of this rtx says how much space to leave
229   for each difference and is adjusted by branch shortening if
230   CASE_VECTOR_SHORTEN_MODE is defined.
231   The third and fourth operands store the target labels with the
232   minimum and maximum addresses respectively.
233   The fifth operand stores flags for use by branch shortening.
234  Set at the start of shorten_branches:
235   min_align: the minimum alignment for any of the target labels.
236   base_after_vec: true iff BASE is after the ADDR_DIFF_VEC.
237   min_after_vec: true iff minimum addr target label is after the ADDR_DIFF_VEC.
238   max_after_vec: true iff maximum addr target label is after the ADDR_DIFF_VEC.
239   min_after_base: true iff minimum address target label is after BASE.
240   max_after_base: true iff maximum address target label is after BASE.
241  Set by the actual branch shortening process:
242   offset_unsigned: true iff offsets have to be treated as unsigned.
243   scale: scaling that is necessary to make offsets fit into the mode.
244
245   The third, fourth and fifth operands are only valid when
246   CASE_VECTOR_SHORTEN_MODE is defined, and only in an optimizing
247   compilations.  */
248     
249DEF_RTL_EXPR(ADDR_DIFF_VEC, "addr_diff_vec", "eEee0", RTX_EXTRA)
250
251/* Memory prefetch, with attributes supported on some targets.
252   Operand 1 is the address of the memory to fetch.
253   Operand 2 is 1 for a write access, 0 otherwise.
254   Operand 3 is the level of temporal locality; 0 means there is no
255   temporal locality and 1, 2, and 3 are for increasing levels of temporal
256   locality.
257
258   The attributes specified by operands 2 and 3 are ignored for targets
259   whose prefetch instructions do not support them.  */
260DEF_RTL_EXPR(PREFETCH, "prefetch", "eee", RTX_EXTRA)
261
262/* ----------------------------------------------------------------------
263   At the top level of an instruction (perhaps under PARALLEL).
264   ---------------------------------------------------------------------- */
265
266/* Assignment.
267   Operand 1 is the location (REG, MEM, PC, CC0 or whatever) assigned to.
268   Operand 2 is the value stored there.
269   ALL assignment must use SET.
270   Instructions that do multiple assignments must use multiple SET,
271   under PARALLEL.  */
272DEF_RTL_EXPR(SET, "set", "ee", RTX_EXTRA)
273
274/* Indicate something is used in a way that we don't want to explain.
275   For example, subroutine calls will use the register
276   in which the static chain is passed.  */
277DEF_RTL_EXPR(USE, "use", "e", RTX_EXTRA)
278
279/* Indicate something is clobbered in a way that we don't want to explain.
280   For example, subroutine calls will clobber some physical registers
281   (the ones that are by convention not saved).  */
282DEF_RTL_EXPR(CLOBBER, "clobber", "e", RTX_EXTRA)
283
284/* Call a subroutine.
285   Operand 1 is the address to call.
286   Operand 2 is the number of arguments.  */
287
288DEF_RTL_EXPR(CALL, "call", "ee", RTX_EXTRA)
289
290/* Return from a subroutine.  */
291
292DEF_RTL_EXPR(RETURN, "return", "", RTX_EXTRA)
293
294/* Conditional trap.
295   Operand 1 is the condition.
296   Operand 2 is the trap code.
297   For an unconditional trap, make the condition (const_int 1).  */
298DEF_RTL_EXPR(TRAP_IF, "trap_if", "ee", RTX_EXTRA)
299
300/* Placeholder for _Unwind_Resume before we know if a function call
301   or a branch is needed.  Operand 1 is the exception region from
302   which control is flowing.  */
303DEF_RTL_EXPR(RESX, "resx", "i", RTX_EXTRA)
304
305/* ----------------------------------------------------------------------
306   Primitive values for use in expressions.
307   ---------------------------------------------------------------------- */
308
309/* numeric integer constant */
310DEF_RTL_EXPR(CONST_INT, "const_int", "w", RTX_CONST_OBJ)
311
312/* numeric floating point constant.
313   Operands hold the value.  They are all 'w' and there may be from 2 to 6;
314   see real.h.  */
315DEF_RTL_EXPR(CONST_DOUBLE, "const_double", CONST_DOUBLE_FORMAT, RTX_CONST_OBJ)
316
317/* Describes a vector constant.  */
318DEF_RTL_EXPR(CONST_VECTOR, "const_vector", "E", RTX_CONST_OBJ)
319
320/* String constant.  Used for attributes in machine descriptions and
321   for special cases in DWARF2 debug output.  NOT used for source-
322   language string constants.  */
323DEF_RTL_EXPR(CONST_STRING, "const_string", "s", RTX_OBJ)
324
325/* This is used to encapsulate an expression whose value is constant
326   (such as the sum of a SYMBOL_REF and a CONST_INT) so that it will be
327   recognized as a constant operand rather than by arithmetic instructions.  */
328
329DEF_RTL_EXPR(CONST, "const", "e", RTX_CONST_OBJ)
330
331/* program counter.  Ordinary jumps are represented
332   by a SET whose first operand is (PC).  */
333DEF_RTL_EXPR(PC, "pc", "", RTX_OBJ)
334
335/* Used in the cselib routines to describe a value.  Objects of this
336   kind are only allocated in cselib.c, in an alloc pool instead of
337   in GC memory.  The only operand of a VALUE is a cselib_val_struct.  */
338DEF_RTL_EXPR(VALUE, "value", "0", RTX_OBJ)
339
340/* A register.  The "operand" is the register number, accessed with
341   the REGNO macro.  If this number is less than FIRST_PSEUDO_REGISTER
342   than a hardware register is being referred to.  The second operand
343   holds the original register number - this will be different for a
344   pseudo register that got turned into a hard register.  The third
345   operand points to a reg_attrs structure.
346   This rtx needs to have as many (or more) fields as a MEM, since we
347   can change REG rtx's into MEMs during reload.  */
348DEF_RTL_EXPR(REG, "reg", "i00", RTX_OBJ)
349
350/* A scratch register.  This represents a register used only within a
351   single insn.  It will be turned into a REG during register allocation
352   or reload unless the constraint indicates that the register won't be
353   needed, in which case it can remain a SCRATCH.  This code is
354   marked as having one operand so it can be turned into a REG.  */
355DEF_RTL_EXPR(SCRATCH, "scratch", "0", RTX_OBJ)
356
357/* One word of a multi-word value.
358   The first operand is the complete value; the second says which word.
359   The WORDS_BIG_ENDIAN flag controls whether word number 0
360   (as numbered in a SUBREG) is the most or least significant word.
361
362   This is also used to refer to a value in a different machine mode.
363   For example, it can be used to refer to a SImode value as if it were
364   Qimode, or vice versa.  Then the word number is always 0.  */
365DEF_RTL_EXPR(SUBREG, "subreg", "ei", RTX_EXTRA)
366
367/* This one-argument rtx is used for move instructions
368   that are guaranteed to alter only the low part of a destination.
369   Thus, (SET (SUBREG:HI (REG...)) (MEM:HI ...))
370   has an unspecified effect on the high part of REG,
371   but (SET (STRICT_LOW_PART (SUBREG:HI (REG...))) (MEM:HI ...))
372   is guaranteed to alter only the bits of REG that are in HImode.
373
374   The actual instruction used is probably the same in both cases,
375   but the register constraints may be tighter when STRICT_LOW_PART
376   is in use.  */
377
378DEF_RTL_EXPR(STRICT_LOW_PART, "strict_low_part", "e", RTX_EXTRA)
379
380/* (CONCAT a b) represents the virtual concatenation of a and b
381   to make a value that has as many bits as a and b put together.
382   This is used for complex values.  Normally it appears only
383   in DECL_RTLs and during RTL generation, but not in the insn chain.  */
384DEF_RTL_EXPR(CONCAT, "concat", "ee", RTX_OBJ)
385
386/* A memory location; operand is the address.  The second operand is the
387   alias set to which this MEM belongs.  We use `0' instead of `w' for this
388   field so that the field need not be specified in machine descriptions.  */
389DEF_RTL_EXPR(MEM, "mem", "e0", RTX_OBJ)
390
391/* Reference to an assembler label in the code for this function.
392   The operand is a CODE_LABEL found in the insn chain.
393   The unprinted field 1 is used in flow.c for the LABEL_NEXTREF.  */
394DEF_RTL_EXPR(LABEL_REF, "label_ref", "u0", RTX_CONST_OBJ)
395
396/* Reference to a named label: 
397   Operand 0: label name
398   Operand 1: flags (see SYMBOL_FLAG_* in rtl.h)
399   Operand 2: tree from which this symbol is derived, or null.
400   This is either a DECL node, or some kind of constant.  */
401DEF_RTL_EXPR(SYMBOL_REF, "symbol_ref", "s00", RTX_CONST_OBJ)
402
403/* The condition code register is represented, in our imagination,
404   as a register holding a value that can be compared to zero.
405   In fact, the machine has already compared them and recorded the
406   results; but instructions that look at the condition code
407   pretend to be looking at the entire value and comparing it.  */
408DEF_RTL_EXPR(CC0, "cc0", "", RTX_OBJ)
409
410/* ----------------------------------------------------------------------
411   Expressions for operators in an rtl pattern
412   ---------------------------------------------------------------------- */
413
414/* if_then_else.  This is used in representing ordinary
415   conditional jump instructions.
416     Operand:
417     0:  condition
418     1:  then expr
419     2:  else expr */
420DEF_RTL_EXPR(IF_THEN_ELSE, "if_then_else", "eee", RTX_TERNARY)
421
422/* Comparison, produces a condition code result.  */
423DEF_RTL_EXPR(COMPARE, "compare", "ee", RTX_BIN_ARITH)
424
425/* plus */
426DEF_RTL_EXPR(PLUS, "plus", "ee", RTX_COMM_ARITH)
427
428/* Operand 0 minus operand 1.  */
429DEF_RTL_EXPR(MINUS, "minus", "ee", RTX_BIN_ARITH)
430
431/* Minus operand 0.  */
432DEF_RTL_EXPR(NEG, "neg", "e", RTX_UNARY)
433
434DEF_RTL_EXPR(MULT, "mult", "ee", RTX_COMM_ARITH)
435
436/* Operand 0 divided by operand 1.  */
437DEF_RTL_EXPR(DIV, "div", "ee", RTX_BIN_ARITH)
438/* Remainder of operand 0 divided by operand 1.  */
439DEF_RTL_EXPR(MOD, "mod", "ee", RTX_BIN_ARITH)
440
441/* Unsigned divide and remainder.  */
442DEF_RTL_EXPR(UDIV, "udiv", "ee", RTX_BIN_ARITH)
443DEF_RTL_EXPR(UMOD, "umod", "ee", RTX_BIN_ARITH)
444
445/* Bitwise operations.  */
446DEF_RTL_EXPR(AND, "and", "ee", RTX_COMM_ARITH)
447DEF_RTL_EXPR(IOR, "ior", "ee", RTX_COMM_ARITH)
448DEF_RTL_EXPR(XOR, "xor", "ee", RTX_COMM_ARITH)
449DEF_RTL_EXPR(NOT, "not", "e", RTX_UNARY)
450
451/* Operand:
452     0:  value to be shifted.
453     1:  number of bits.  */
454DEF_RTL_EXPR(ASHIFT, "ashift", "ee", RTX_BIN_ARITH) /* shift left */
455DEF_RTL_EXPR(ROTATE, "rotate", "ee", RTX_BIN_ARITH) /* rotate left */
456DEF_RTL_EXPR(ASHIFTRT, "ashiftrt", "ee", RTX_BIN_ARITH) /* arithmetic shift right */
457DEF_RTL_EXPR(LSHIFTRT, "lshiftrt", "ee", RTX_BIN_ARITH) /* logical shift right */
458DEF_RTL_EXPR(ROTATERT, "rotatert", "ee", RTX_BIN_ARITH) /* rotate right */
459
460/* Minimum and maximum values of two operands.  We need both signed and
461   unsigned forms.  (We cannot use MIN for SMIN because it conflicts
462   with a macro of the same name.)   The signed variants should be used
463   with floating point.  Further, if both operands are zeros, or if either
464   operand is NaN, then it is unspecified which of the two operands is
465   returned as the result.  */
466
467DEF_RTL_EXPR(SMIN, "smin", "ee", RTX_COMM_ARITH)
468DEF_RTL_EXPR(SMAX, "smax", "ee", RTX_COMM_ARITH)
469DEF_RTL_EXPR(UMIN, "umin", "ee", RTX_COMM_ARITH)
470DEF_RTL_EXPR(UMAX, "umax", "ee", RTX_COMM_ARITH)
471
472/* These unary operations are used to represent incrementation
473   and decrementation as they occur in memory addresses.
474   The amount of increment or decrement are not represented
475   because they can be understood from the machine-mode of the
476   containing MEM.  These operations exist in only two cases:
477   1. pushes onto the stack.
478   2. created automatically by the life_analysis pass in flow.c.  */
479DEF_RTL_EXPR(PRE_DEC, "pre_dec", "e", RTX_AUTOINC)
480DEF_RTL_EXPR(PRE_INC, "pre_inc", "e", RTX_AUTOINC)
481DEF_RTL_EXPR(POST_DEC, "post_dec", "e", RTX_AUTOINC)
482DEF_RTL_EXPR(POST_INC, "post_inc", "e", RTX_AUTOINC)
483
484/* These binary operations are used to represent generic address
485   side-effects in memory addresses, except for simple incrementation
486   or decrementation which use the above operations.  They are
487   created automatically by the life_analysis pass in flow.c.
488   The first operand is a REG which is used as the address.
489   The second operand is an expression that is assigned to the
490   register, either before (PRE_MODIFY) or after (POST_MODIFY)
491   evaluating the address.
492   Currently, the compiler can only handle second operands of the
493   form (plus (reg) (reg)) and (plus (reg) (const_int)), where
494   the first operand of the PLUS has to be the same register as
495   the first operand of the *_MODIFY.  */
496DEF_RTL_EXPR(PRE_MODIFY, "pre_modify", "ee", RTX_AUTOINC)
497DEF_RTL_EXPR(POST_MODIFY, "post_modify", "ee", RTX_AUTOINC)
498
499/* Comparison operations.  The ordered comparisons exist in two
500   flavors, signed and unsigned.  */
501DEF_RTL_EXPR(NE, "ne", "ee", RTX_COMM_COMPARE)
502DEF_RTL_EXPR(EQ, "eq", "ee", RTX_COMM_COMPARE)
503DEF_RTL_EXPR(GE, "ge", "ee", RTX_COMPARE)
504DEF_RTL_EXPR(GT, "gt", "ee", RTX_COMPARE)
505DEF_RTL_EXPR(LE, "le", "ee", RTX_COMPARE)
506DEF_RTL_EXPR(LT, "lt", "ee", RTX_COMPARE)
507DEF_RTL_EXPR(GEU, "geu", "ee", RTX_COMPARE)
508DEF_RTL_EXPR(GTU, "gtu", "ee", RTX_COMPARE)
509DEF_RTL_EXPR(LEU, "leu", "ee", RTX_COMPARE)
510DEF_RTL_EXPR(LTU, "ltu", "ee", RTX_COMPARE)
511
512/* Additional floating point unordered comparison flavors.  */
513DEF_RTL_EXPR(UNORDERED, "unordered", "ee", RTX_COMM_COMPARE)
514DEF_RTL_EXPR(ORDERED, "ordered", "ee", RTX_COMM_COMPARE)
515
516/* These are equivalent to unordered or ...  */
517DEF_RTL_EXPR(UNEQ, "uneq", "ee", RTX_COMM_COMPARE)
518DEF_RTL_EXPR(UNGE, "unge", "ee", RTX_COMPARE)
519DEF_RTL_EXPR(UNGT, "ungt", "ee", RTX_COMPARE)
520DEF_RTL_EXPR(UNLE, "unle", "ee", RTX_COMPARE)
521DEF_RTL_EXPR(UNLT, "unlt", "ee", RTX_COMPARE)
522
523/* This is an ordered NE, ie !UNEQ, ie false for NaN.  */
524DEF_RTL_EXPR(LTGT, "ltgt", "ee", RTX_COMM_COMPARE)
525
526/* Represents the result of sign-extending the sole operand.
527   The machine modes of the operand and of the SIGN_EXTEND expression
528   determine how much sign-extension is going on.  */
529DEF_RTL_EXPR(SIGN_EXTEND, "sign_extend", "e", RTX_UNARY)
530
531/* Similar for zero-extension (such as unsigned short to int).  */
532DEF_RTL_EXPR(ZERO_EXTEND, "zero_extend", "e", RTX_UNARY)
533
534/* Similar but here the operand has a wider mode.  */
535DEF_RTL_EXPR(TRUNCATE, "truncate", "e", RTX_UNARY)
536
537/* Similar for extending floating-point values (such as SFmode to DFmode).  */
538DEF_RTL_EXPR(FLOAT_EXTEND, "float_extend", "e", RTX_UNARY)
539DEF_RTL_EXPR(FLOAT_TRUNCATE, "float_truncate", "e", RTX_UNARY)
540
541/* Conversion of fixed point operand to floating point value.  */
542DEF_RTL_EXPR(FLOAT, "float", "e", RTX_UNARY)
543
544/* With fixed-point machine mode:
545   Conversion of floating point operand to fixed point value.
546   Value is defined only when the operand's value is an integer.
547   With floating-point machine mode (and operand with same mode):
548   Operand is rounded toward zero to produce an integer value
549   represented in floating point.  */
550DEF_RTL_EXPR(FIX, "fix", "e", RTX_UNARY)
551
552/* Conversion of unsigned fixed point operand to floating point value.  */
553DEF_RTL_EXPR(UNSIGNED_FLOAT, "unsigned_float", "e", RTX_UNARY)
554
555/* With fixed-point machine mode:
556   Conversion of floating point operand to *unsigned* fixed point value.
557   Value is defined only when the operand's value is an integer.  */
558DEF_RTL_EXPR(UNSIGNED_FIX, "unsigned_fix", "e", RTX_UNARY)
559
560/* Absolute value */
561DEF_RTL_EXPR(ABS, "abs", "e", RTX_UNARY)
562
563/* Square root */
564DEF_RTL_EXPR(SQRT, "sqrt", "e", RTX_UNARY)
565
566/* Find first bit that is set.
567   Value is 1 + number of trailing zeros in the arg.,
568   or 0 if arg is 0.  */
569DEF_RTL_EXPR(FFS, "ffs", "e", RTX_UNARY)
570
571/* Count leading zeros.  */
572DEF_RTL_EXPR(CLZ, "clz", "e", RTX_UNARY)
573
574/* Count trailing zeros.  */
575DEF_RTL_EXPR(CTZ, "ctz", "e", RTX_UNARY)
576
577/* Population count (number of 1 bits).  */
578DEF_RTL_EXPR(POPCOUNT, "popcount", "e", RTX_UNARY)
579
580/* Population parity (number of 1 bits modulo 2).  */
581DEF_RTL_EXPR(PARITY, "parity", "e", RTX_UNARY)
582
583/* Reference to a signed bit-field of specified size and position.
584   Operand 0 is the memory unit (usually SImode or QImode) which
585   contains the field's first bit.  Operand 1 is the width, in bits.
586   Operand 2 is the number of bits in the memory unit before the
587   first bit of this field.
588   If BITS_BIG_ENDIAN is defined, the first bit is the msb and
589   operand 2 counts from the msb of the memory unit.
590   Otherwise, the first bit is the lsb and operand 2 counts from
591   the lsb of the memory unit.
592   This kind of expression can not appear as an lvalue in RTL.  */
593DEF_RTL_EXPR(SIGN_EXTRACT, "sign_extract", "eee", RTX_BITFIELD_OPS)
594
595/* Similar for unsigned bit-field.
596   But note!  This kind of expression _can_ appear as an lvalue.  */
597DEF_RTL_EXPR(ZERO_EXTRACT, "zero_extract", "eee", RTX_BITFIELD_OPS)
598
599/* For RISC machines.  These save memory when splitting insns.  */
600
601/* HIGH are the high-order bits of a constant expression.  */
602DEF_RTL_EXPR(HIGH, "high", "e", RTX_CONST_OBJ)
603
604/* LO_SUM is the sum of a register and the low-order bits
605   of a constant expression.  */
606DEF_RTL_EXPR(LO_SUM, "lo_sum", "ee", RTX_OBJ)
607
608/* Describes a merge operation between two vector values.
609   Operands 0 and 1 are the vectors to be merged, operand 2 is a bitmask
610   that specifies where the parts of the result are taken from.  Set bits
611   indicate operand 0, clear bits indicate operand 1.  The parts are defined
612   by the mode of the vectors.  */
613DEF_RTL_EXPR(VEC_MERGE, "vec_merge", "eee", RTX_TERNARY)
614
615/* Describes an operation that selects parts of a vector.
616   Operands 0 is the source vector, operand 1 is a PARALLEL that contains
617   a CONST_INT for each of the subparts of the result vector, giving the
618   number of the source subpart that should be stored into it.  */
619DEF_RTL_EXPR(VEC_SELECT, "vec_select", "ee", RTX_BIN_ARITH)
620
621/* Describes a vector concat operation.  Operands 0 and 1 are the source
622   vectors, the result is a vector that is as long as operands 0 and 1
623   combined and is the concatenation of the two source vectors.  */
624DEF_RTL_EXPR(VEC_CONCAT, "vec_concat", "ee", RTX_BIN_ARITH)
625
626/* Describes an operation that converts a small vector into a larger one by
627   duplicating the input values.  The output vector mode must have the same
628   submodes as the input vector mode, and the number of output parts must be
629   an integer multiple of the number of input parts.  */
630DEF_RTL_EXPR(VEC_DUPLICATE, "vec_duplicate", "e", RTX_UNARY)
631     
632/* Addition with signed saturation */
633DEF_RTL_EXPR(SS_PLUS, "ss_plus", "ee", RTX_COMM_ARITH)
634
635/* Addition with unsigned saturation */
636DEF_RTL_EXPR(US_PLUS, "us_plus", "ee", RTX_COMM_ARITH)
637
638/* Operand 0 minus operand 1, with signed saturation.  */
639DEF_RTL_EXPR(SS_MINUS, "ss_minus", "ee", RTX_BIN_ARITH)
640
641/* Operand 0 minus operand 1, with unsigned saturation.  */
642DEF_RTL_EXPR(US_MINUS, "us_minus", "ee", RTX_BIN_ARITH)
643
644/* Signed saturating truncate.  */
645DEF_RTL_EXPR(SS_TRUNCATE, "ss_truncate", "e", RTX_UNARY)
646
647/* Unsigned saturating truncate.  */
648DEF_RTL_EXPR(US_TRUNCATE, "us_truncate", "e", RTX_UNARY)
649
650/* Information about the variable and its location.  */
651DEF_RTL_EXPR(VAR_LOCATION, "var_location", "te", RTX_EXTRA)
652
653/* All expressions from this point forward appear only in machine
654   descriptions.  */
655#ifdef GENERATOR_FILE
656
657/* Include a secondary machine-description file at this point.  */
658DEF_RTL_EXPR(INCLUDE, "include", "s", RTX_EXTRA)
659
660/* Pattern-matching operators:  */
661
662/* Use the function named by the second arg (the string)
663   as a predicate; if matched, store the structure that was matched
664   in the operand table at index specified by the first arg (the integer).
665   If the second arg is the null string, the structure is just stored.
666
667   A third string argument indicates to the register allocator restrictions
668   on where the operand can be allocated.
669
670   If the target needs no restriction on any instruction this field should
671   be the null string.
672
673   The string is prepended by:
674   '=' to indicate the operand is only written to.
675   '+' to indicate the operand is both read and written to.
676
677   Each character in the string represents an allocable class for an operand.
678   'g' indicates the operand can be any valid class.
679   'i' indicates the operand can be immediate (in the instruction) data.
680   'r' indicates the operand can be in a register.
681   'm' indicates the operand can be in memory.
682   'o' a subset of the 'm' class.  Those memory addressing modes that
683       can be offset at compile time (have a constant added to them).
684
685   Other characters indicate target dependent operand classes and
686   are described in each target's machine description.
687
688   For instructions with more than one operand, sets of classes can be
689   separated by a comma to indicate the appropriate multi-operand constraints.
690   There must be a 1 to 1 correspondence between these sets of classes in
691   all operands for an instruction.
692   */
693DEF_RTL_EXPR(MATCH_OPERAND, "match_operand", "iss", RTX_MATCH)
694
695/* Match a SCRATCH or a register.  When used to generate rtl, a
696   SCRATCH is generated.  As for MATCH_OPERAND, the mode specifies
697   the desired mode and the first argument is the operand number.
698   The second argument is the constraint.  */
699DEF_RTL_EXPR(MATCH_SCRATCH, "match_scratch", "is", RTX_MATCH)
700
701/* Apply a predicate, AND match recursively the operands of the rtx.
702   Operand 0 is the operand-number, as in match_operand.
703   Operand 1 is a predicate to apply (as a string, a function name).
704   Operand 2 is a vector of expressions, each of which must match
705   one subexpression of the rtx this construct is matching.  */
706DEF_RTL_EXPR(MATCH_OPERATOR, "match_operator", "isE", RTX_MATCH)
707
708/* Match a PARALLEL of arbitrary length.  The predicate is applied
709   to the PARALLEL and the initial expressions in the PARALLEL are matched.
710   Operand 0 is the operand-number, as in match_operand.
711   Operand 1 is a predicate to apply to the PARALLEL.
712   Operand 2 is a vector of expressions, each of which must match the 
713   corresponding element in the PARALLEL.  */
714DEF_RTL_EXPR(MATCH_PARALLEL, "match_parallel", "isE", RTX_MATCH)
715
716/* Match only something equal to what is stored in the operand table
717   at the index specified by the argument.  Use with MATCH_OPERAND.  */
718DEF_RTL_EXPR(MATCH_DUP, "match_dup", "i", RTX_MATCH)
719
720/* Match only something equal to what is stored in the operand table
721   at the index specified by the argument.  Use with MATCH_OPERATOR.  */
722DEF_RTL_EXPR(MATCH_OP_DUP, "match_op_dup", "iE", RTX_MATCH)
723
724/* Match only something equal to what is stored in the operand table
725   at the index specified by the argument.  Use with MATCH_PARALLEL.  */
726DEF_RTL_EXPR(MATCH_PAR_DUP, "match_par_dup", "iE", RTX_MATCH)
727
728/* Appears only in define_predicate/define_special_predicate
729   expressions.  Evaluates true only if the operand has an RTX code
730   from the set given by the argument (a comma-separated list).  */
731DEF_RTL_EXPR(MATCH_CODE, "match_code", "s", RTX_MATCH)
732
733/* Appears only in define_predicate/define_special_predicate
734    expressions.  The argument is a C expression to be injected at this
735    point in the predicate formula.  */
736DEF_RTL_EXPR(MATCH_TEST, "match_test", "s", RTX_MATCH)
737
738/* Insn (and related) definitions.  */
739
740/* Definition of the pattern for one kind of instruction.
741   Operand:
742   0: names this instruction.
743      If the name is the null string, the instruction is in the
744      machine description just to be recognized, and will never be emitted by
745      the tree to rtl expander.
746   1: is the pattern.
747   2: is a string which is a C expression
748      giving an additional condition for recognizing this pattern.
749      A null string means no extra condition.
750   3: is the action to execute if this pattern is matched.
751      If this assembler code template starts with a * then it is a fragment of
752      C code to run to decide on a template to use.  Otherwise, it is the
753      template to use.
754   4: optionally, a vector of attributes for this insn.
755     */
756DEF_RTL_EXPR(DEFINE_INSN, "define_insn", "sEsTV", RTX_EXTRA)
757
758/* Definition of a peephole optimization.
759   1st operand: vector of insn patterns to match
760   2nd operand: C expression that must be true
761   3rd operand: template or C code to produce assembler output.
762   4: optionally, a vector of attributes for this insn.
763
764   This form is deprecated; use define_peephole2 instead.  */
765DEF_RTL_EXPR(DEFINE_PEEPHOLE, "define_peephole", "EsTV", RTX_EXTRA)
766
767/* Definition of a split operation.
768   1st operand: insn pattern to match
769   2nd operand: C expression that must be true
770   3rd operand: vector of insn patterns to place into a SEQUENCE
771   4th operand: optionally, some C code to execute before generating the
772	insns.  This might, for example, create some RTX's and store them in
773	elements of `recog_data.operand' for use by the vector of
774	insn-patterns.
775	(`operands' is an alias here for `recog_data.operand').  */
776DEF_RTL_EXPR(DEFINE_SPLIT, "define_split", "EsES", RTX_EXTRA)
777
778/* Definition of an insn and associated split.
779   This is the concatenation, with a few modifications, of a define_insn
780   and a define_split which share the same pattern.
781   Operand:
782   0: names this instruction.
783      If the name is the null string, the instruction is in the
784      machine description just to be recognized, and will never be emitted by
785      the tree to rtl expander.
786   1: is the pattern.
787   2: is a string which is a C expression
788      giving an additional condition for recognizing this pattern.
789      A null string means no extra condition.
790   3: is the action to execute if this pattern is matched.
791      If this assembler code template starts with a * then it is a fragment of
792      C code to run to decide on a template to use.  Otherwise, it is the
793      template to use.
794   4: C expression that must be true for split.  This may start with "&&"
795      in which case the split condition is the logical and of the insn 
796      condition and what follows the "&&" of this operand.
797   5: vector of insn patterns to place into a SEQUENCE
798   6: optionally, some C code to execute before generating the
799	insns.  This might, for example, create some RTX's and store them in
800	elements of `recog_data.operand' for use by the vector of
801	insn-patterns.
802	(`operands' is an alias here for `recog_data.operand').  
803   7: optionally, a vector of attributes for this insn.  */
804DEF_RTL_EXPR(DEFINE_INSN_AND_SPLIT, "define_insn_and_split", "sEsTsESV", RTX_EXTRA)
805
806/* Definition of an RTL peephole operation.
807   Follows the same arguments as define_split.  */
808DEF_RTL_EXPR(DEFINE_PEEPHOLE2, "define_peephole2", "EsES", RTX_EXTRA)
809
810/* Define how to generate multiple insns for a standard insn name.
811   1st operand: the insn name.
812   2nd operand: vector of insn-patterns.
813	Use match_operand to substitute an element of `recog_data.operand'.
814   3rd operand: C expression that must be true for this to be available.
815	This may not test any operands.
816   4th operand: Extra C code to execute before generating the insns.
817	This might, for example, create some RTX's and store them in
818	elements of `recog_data.operand' for use by the vector of
819	insn-patterns.
820	(`operands' is an alias here for `recog_data.operand').  */
821DEF_RTL_EXPR(DEFINE_EXPAND, "define_expand", "sEss", RTX_EXTRA)
822   
823/* Define a requirement for delay slots.
824   1st operand: Condition involving insn attributes that, if true,
825	        indicates that the insn requires the number of delay slots
826		shown.
827   2nd operand: Vector whose length is the three times the number of delay
828		slots required.
829	        Each entry gives three conditions, each involving attributes.
830		The first must be true for an insn to occupy that delay slot
831		location.  The second is true for all insns that can be
832		annulled if the branch is true and the third is true for all
833		insns that can be annulled if the branch is false. 
834
835   Multiple DEFINE_DELAYs may be present.  They indicate differing
836   requirements for delay slots.  */
837DEF_RTL_EXPR(DEFINE_DELAY, "define_delay", "eE", RTX_EXTRA)
838
839/* Define attribute computation for `asm' instructions.  */
840DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES, "define_asm_attributes", "V", RTX_EXTRA)
841
842/* Definition of a conditional execution meta operation.  Automatically
843   generates new instances of DEFINE_INSN, selected by having attribute
844   "predicable" true.  The new pattern will contain a COND_EXEC and the
845   predicate at top-level.
846
847   Operand:
848   0: The predicate pattern.  The top-level form should match a
849      relational operator.  Operands should have only one alternative.
850   1: A C expression giving an additional condition for recognizing
851      the generated pattern.
852   2: A template or C code to produce assembler output.  */
853DEF_RTL_EXPR(DEFINE_COND_EXEC, "define_cond_exec", "Ess", RTX_EXTRA)
854
855/* Definition of an operand predicate.  The difference between
856   DEFINE_PREDICATE and DEFINE_SPECIAL_PREDICATE is that genrecog will
857   not warn about a match_operand with no mode if it has a predicate
858   defined with DEFINE_SPECIAL_PREDICATE.
859
860   Operand:
861   0: The name of the predicate.
862   1: A boolean expression which computes whether or not the predicate
863      matches.  This expression can use IOR, AND, NOT, MATCH_OPERAND,
864      MATCH_CODE, and MATCH_TEST.  It must be specific enough that genrecog
865      can calculate the set of RTX codes that can possibly match.
866   2: A C function body which must return true for the predicate to match.
867      Optional.  Use this when the test is too complicated to fit into a
868      match_test expression.  */
869DEF_RTL_EXPR(DEFINE_PREDICATE, "define_predicate", "ses", RTX_EXTRA)
870DEF_RTL_EXPR(DEFINE_SPECIAL_PREDICATE, "define_special_predicate", "ses", RTX_EXTRA)
871
872/* Constructions for CPU pipeline description described by NDFAs.  */
873
874/* (define_cpu_unit string [string]) describes cpu functional
875   units (separated by comma).
876
877   1st operand: Names of cpu functional units.
878   2nd operand: Name of automaton (see comments for DEFINE_AUTOMATON).
879
880   All define_reservations, define_cpu_units, and
881   define_query_cpu_units should have unique names which may not be
882   "nothing".  */
883DEF_RTL_EXPR(DEFINE_CPU_UNIT, "define_cpu_unit", "sS", RTX_EXTRA)
884
885/* (define_query_cpu_unit string [string]) describes cpu functional
886   units analogously to define_cpu_unit.  The reservation of such
887   units can be queried for automaton state.  */
888DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT, "define_query_cpu_unit", "sS", RTX_EXTRA)
889
890/* (exclusion_set string string) means that each CPU functional unit
891   in the first string can not be reserved simultaneously with any
892   unit whose name is in the second string and vise versa.  CPU units
893   in the string are separated by commas.  For example, it is useful
894   for description CPU with fully pipelined floating point functional
895   unit which can execute simultaneously only single floating point
896   insns or only double floating point insns.  All CPU functional
897   units in a set should belong to the same automaton.  */
898DEF_RTL_EXPR(EXCLUSION_SET, "exclusion_set", "ss", RTX_EXTRA)
899
900/* (presence_set string string) means that each CPU functional unit in
901   the first string can not be reserved unless at least one of pattern
902   of units whose names are in the second string is reserved.  This is
903   an asymmetric relation.  CPU units or unit patterns in the strings
904   are separated by commas.  Pattern is one unit name or unit names
905   separated by white-spaces.
906 
907   For example, it is useful for description that slot1 is reserved
908   after slot0 reservation for a VLIW processor.  We could describe it
909   by the following construction
910
911      (presence_set "slot1" "slot0")
912
913   Or slot1 is reserved only after slot0 and unit b0 reservation.  In
914   this case we could write
915
916      (presence_set "slot1" "slot0 b0")
917
918   All CPU functional units in a set should belong to the same
919   automaton.  */
920DEF_RTL_EXPR(PRESENCE_SET, "presence_set", "ss", RTX_EXTRA)
921
922/* (final_presence_set string string) is analogous to `presence_set'.
923   The difference between them is when checking is done.  When an
924   instruction is issued in given automaton state reflecting all
925   current and planned unit reservations, the automaton state is
926   changed.  The first state is a source state, the second one is a
927   result state.  Checking for `presence_set' is done on the source
928   state reservation, checking for `final_presence_set' is done on the
929   result reservation.  This construction is useful to describe a
930   reservation which is actually two subsequent reservations.  For
931   example, if we use 
932
933      (presence_set "slot1" "slot0")
934
935   the following insn will be never issued (because slot1 requires
936   slot0 which is absent in the source state).
937
938      (define_reservation "insn_and_nop" "slot0 + slot1")
939
940   but it can be issued if we use analogous `final_presence_set'.  */
941DEF_RTL_EXPR(FINAL_PRESENCE_SET, "final_presence_set", "ss", RTX_EXTRA)
942
943/* (absence_set string string) means that each CPU functional unit in
944   the first string can be reserved only if each pattern of units
945   whose names are in the second string is not reserved.  This is an
946   asymmetric relation (actually exclusion set is analogous to this
947   one but it is symmetric).  CPU units or unit patterns in the string
948   are separated by commas.  Pattern is one unit name or unit names
949   separated by white-spaces.
950
951   For example, it is useful for description that slot0 can not be
952   reserved after slot1 or slot2 reservation for a VLIW processor.  We
953   could describe it by the following construction
954
955      (absence_set "slot2" "slot0, slot1")
956
957   Or slot2 can not be reserved if slot0 and unit b0 are reserved or
958   slot1 and unit b1 are reserved .  In this case we could write
959
960      (absence_set "slot2" "slot0 b0, slot1 b1")
961
962   All CPU functional units in a set should to belong the same
963   automaton.  */
964DEF_RTL_EXPR(ABSENCE_SET, "absence_set", "ss", RTX_EXTRA)
965
966/* (final_absence_set string string) is analogous to `absence_set' but
967   checking is done on the result (state) reservation.  See comments
968   for `final_presence_set'.  */
969DEF_RTL_EXPR(FINAL_ABSENCE_SET, "final_absence_set", "ss", RTX_EXTRA)
970
971/* (define_bypass number out_insn_names in_insn_names) names bypass
972   with given latency (the first number) from insns given by the first
973   string (see define_insn_reservation) into insns given by the second
974   string.  Insn names in the strings are separated by commas.  The
975   third operand is optional name of function which is additional
976   guard for the bypass.  The function will get the two insns as
977   parameters.  If the function returns zero the bypass will be
978   ignored for this case.  Additional guard is necessary to recognize
979   complicated bypasses, e.g. when consumer is load address.  */
980DEF_RTL_EXPR(DEFINE_BYPASS, "define_bypass", "issS", RTX_EXTRA)
981
982/* (define_automaton string) describes names of automata generated and
983   used for pipeline hazards recognition.  The names are separated by
984   comma.  Actually it is possibly to generate the single automaton
985   but unfortunately it can be very large.  If we use more one
986   automata, the summary size of the automata usually is less than the
987   single one.  The automaton name is used in define_cpu_unit and
988   define_query_cpu_unit.  All automata should have unique names.  */
989DEF_RTL_EXPR(DEFINE_AUTOMATON, "define_automaton", "s", RTX_EXTRA)
990
991/* (automata_option string) describes option for generation of
992   automata.  Currently there are the following options:
993
994   o "no-minimization" which makes no minimization of automata.  This
995     is only worth to do when we are debugging the description and
996     need to look more accurately at reservations of states.
997
998   o "time" which means printing additional time statistics about
999      generation of automata.
1000  
1001   o "v" which means generation of file describing the result
1002     automata.  The file has suffix `.dfa' and can be used for the
1003     description verification and debugging.
1004
1005   o "w" which means generation of warning instead of error for
1006     non-critical errors.
1007
1008   o "ndfa" which makes nondeterministic finite state automata.
1009
1010   o "progress" which means output of a progress bar showing how many
1011     states were generated so far for automaton being processed.  */
1012DEF_RTL_EXPR(AUTOMATA_OPTION, "automata_option", "s", RTX_EXTRA)
1013
1014/* (define_reservation string string) names reservation (the first
1015   string) of cpu functional units (the 2nd string).  Sometimes unit
1016   reservations for different insns contain common parts.  In such
1017   case, you can describe common part and use its name (the 1st
1018   parameter) in regular expression in define_insn_reservation.  All
1019   define_reservations, define_cpu_units, and define_query_cpu_units
1020   should have unique names which may not be "nothing".  */
1021DEF_RTL_EXPR(DEFINE_RESERVATION, "define_reservation", "ss", RTX_EXTRA)
1022
1023/* (define_insn_reservation name default_latency condition regexpr)
1024   describes reservation of cpu functional units (the 3nd operand) for
1025   instruction which is selected by the condition (the 2nd parameter).
1026   The first parameter is used for output of debugging information.
1027   The reservations are described by a regular expression according
1028   the following syntax:
1029
1030       regexp = regexp "," oneof
1031              | oneof
1032
1033       oneof = oneof "|" allof
1034             | allof
1035
1036       allof = allof "+" repeat
1037             | repeat
1038 
1039       repeat = element "*" number
1040              | element
1041
1042       element = cpu_function_unit_name
1043               | reservation_name
1044               | result_name
1045               | "nothing"
1046               | "(" regexp ")"
1047
1048       1. "," is used for describing start of the next cycle in
1049       reservation.
1050
1051       2. "|" is used for describing the reservation described by the
1052       first regular expression *or* the reservation described by the
1053       second regular expression *or* etc.
1054
1055       3. "+" is used for describing the reservation described by the
1056       first regular expression *and* the reservation described by the
1057       second regular expression *and* etc.
1058
1059       4. "*" is used for convenience and simply means sequence in
1060       which the regular expression are repeated NUMBER times with
1061       cycle advancing (see ",").
1062
1063       5. cpu functional unit name which means its reservation.
1064
1065       6. reservation name -- see define_reservation.
1066
1067       7. string "nothing" means no units reservation.  */
1068
1069DEF_RTL_EXPR(DEFINE_INSN_RESERVATION, "define_insn_reservation", "sies", RTX_EXTRA)
1070
1071/* Expressions used for insn attributes.  */
1072
1073/* Definition of an insn attribute.
1074   1st operand: name of the attribute
1075   2nd operand: comma-separated list of possible attribute values
1076   3rd operand: expression for the default value of the attribute.  */
1077DEF_RTL_EXPR(DEFINE_ATTR, "define_attr", "sse", RTX_EXTRA)
1078
1079/* Marker for the name of an attribute.  */
1080DEF_RTL_EXPR(ATTR, "attr", "s", RTX_EXTRA)
1081
1082/* For use in the last (optional) operand of DEFINE_INSN or DEFINE_PEEPHOLE and
1083   in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that
1084   pattern.
1085
1086   (set_attr "name" "value") is equivalent to
1087   (set (attr "name") (const_string "value"))  */
1088DEF_RTL_EXPR(SET_ATTR, "set_attr", "ss", RTX_EXTRA)
1089
1090/* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE, this can be used to
1091   specify that attribute values are to be assigned according to the
1092   alternative matched.
1093
1094   The following three expressions are equivalent:
1095
1096   (set (attr "att") (cond [(eq_attrq "alternative" "1") (const_string "a1")
1097			    (eq_attrq "alternative" "2") (const_string "a2")]
1098			   (const_string "a3")))
1099   (set_attr_alternative "att" [(const_string "a1") (const_string "a2")
1100				 (const_string "a3")])
1101   (set_attr "att" "a1,a2,a3")
1102 */
1103DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE, "set_attr_alternative", "sE", RTX_EXTRA)
1104
1105/* A conditional expression true if the value of the specified attribute of
1106   the current insn equals the specified value.  The first operand is the
1107   attribute name and the second is the comparison value.  */
1108DEF_RTL_EXPR(EQ_ATTR, "eq_attr", "ss", RTX_EXTRA)
1109
1110/* A special case of the above representing a set of alternatives.  The first
1111   operand is bitmap of the set, the second one is the default value.  */
1112DEF_RTL_EXPR(EQ_ATTR_ALT, "eq_attr_alt", "ii", RTX_EXTRA)
1113
1114/* A conditional expression which is true if the specified flag is
1115   true for the insn being scheduled in reorg.
1116
1117   genattr.c defines the following flags which can be tested by
1118   (attr_flag "foo") expressions in eligible_for_delay.
1119
1120   forward, backward, very_likely, likely, very_unlikely, and unlikely.  */
1121
1122DEF_RTL_EXPR (ATTR_FLAG, "attr_flag", "s", RTX_EXTRA)
1123
1124/* General conditional. The first operand is a vector composed of pairs of
1125   expressions.  The first element of each pair is evaluated, in turn.
1126   The value of the conditional is the second expression of the first pair
1127   whose first expression evaluates nonzero.  If none of the expressions is
1128   true, the second operand will be used as the value of the conditional.  */
1129DEF_RTL_EXPR(COND, "cond", "Ee", RTX_EXTRA)
1130
1131#endif /* GENERATOR_FILE */
1132
1133/*
1134Local variables:
1135mode:c
1136End:
1137*/
1138