gcc/rtl.def

   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) 1987-2014 Free Software Foundation, Inc.
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22
  23 /* Expression definitions and descriptions for all targets are in this file.
  24    Some will not be used for some targets.
  25
  26    The fields in the cpp macro call "DEF_RTL_EXPR()"
  27    are used to create declarations in the C source of the compiler.
  28
  29    The fields are:
  30
  31    1.  The internal name of the rtx used in the C source.
  32    It is a tag in the enumeration "enum rtx_code" defined in "rtl.h".
  33    By convention these are in UPPER_CASE.
  34
  35    2.  The name of the rtx in the external ASCII format read by
  36    read_rtx(), and printed by print_rtx().
  37    These names are stored in rtx_name[].
  38    By convention these are the internal (field 1) names in lower_case.
  39
  40    3.  The print format, and type of each rtx->u.fld[] (field) in this rtx.
  41    These formats are stored in rtx_format[].
  42    The meaning of the formats is documented in front of this array in rtl.c
  43
  44    4.  The class of the rtx.  These are stored in rtx_class and are accessed
  45    via the GET_RTX_CLASS macro.  They are defined as follows:
  46
  47      RTX_CONST_OBJ
  48          an rtx code that can be used to represent a constant object
  49          (e.g, CONST_INT)
  50      RTX_OBJ
  51          an rtx code that can be used to represent an object (e.g, REG, MEM)
  52      RTX_COMPARE
  53          an rtx code for a comparison (e.g, LT, GT)
  54      RTX_COMM_COMPARE
  55          an rtx code for a commutative comparison (e.g, EQ, NE, ORDERED)
  56      RTX_UNARY
  57          an rtx code for a unary arithmetic expression (e.g, NEG, NOT)
  58      RTX_COMM_ARITH
  59          an rtx code for a commutative binary operation (e.g,, PLUS, MULT)
  60      RTX_TERNARY
  61          an rtx code for a non-bitfield three input operation (IF_THEN_ELSE)
  62      RTX_BIN_ARITH
  63          an rtx code for a non-commutative binary operation (e.g., MINUS, DIV)
  64      RTX_BITFIELD_OPS
  65          an rtx code for a bit-field operation (ZERO_EXTRACT, SIGN_EXTRACT)
  66      RTX_INSN
  67          an rtx code for a machine insn (INSN, JUMP_INSN, CALL_INSN) or
  68          data that will be output as assembly pseudo-ops (DEBUG_INSN)
  69      RTX_MATCH
  70          an rtx code for something that matches in insns (e.g, MATCH_DUP)
  71      RTX_AUTOINC
  72          an rtx code for autoincrement addressing modes (e.g. POST_DEC)
  73      RTX_EXTRA
  74          everything else
  75
  76    All of the expressions that appear only in machine descriptions,
  77    not in RTL used by the compiler itself, are at the end of the file.  */
  78
  79 /* Unknown, or no such operation; the enumeration constant should have
  80    value zero.  */
  81 DEF_RTL_EXPR(UNKNOWN, "UnKnown", "*", RTX_EXTRA)
  82
  83 /* Used in the cselib routines to describe a value.  Objects of this
  84    kind are only allocated in cselib.c, in an alloc pool instead of in
  85    GC memory.  The only operand of a VALUE is a cselib_val.
  86    var-tracking requires this to have a distinct integral value from
  87    DECL codes in trees.  */
  88 DEF_RTL_EXPR(VALUE, "value", "0", RTX_OBJ)
  89
  90 /* The RTL generated for a DEBUG_EXPR_DECL.  It links back to the
  91    DEBUG_EXPR_DECL in the first operand.  */
  92 DEF_RTL_EXPR(DEBUG_EXPR, "debug_expr", "0", RTX_OBJ)
  93
  94 /* ---------------------------------------------------------------------
  95    Expressions used in constructing lists.
  96    --------------------------------------------------------------------- */
  97
  98 /* A linked list of expressions.  */
  99 DEF_RTL_EXPR(EXPR_LIST, "expr_list", "ee", RTX_EXTRA)
 100
 101 /* A linked list of instructions.
 102    The insns are represented in print by their uids.  */
 103 DEF_RTL_EXPR(INSN_LIST, "insn_list", "ue", RTX_EXTRA)
 104
 105 /* A linked list of integers.  */
 106 DEF_RTL_EXPR(INT_LIST, "int_list", "ie", RTX_EXTRA)
 107
 108 /* SEQUENCE is used in late passes of the compiler to group insns for
 109    one reason or another.
 110
 111    For example, after delay slot filling, branch instructions with filled
 112    delay slots are represented as a SEQUENCE of length 1 + n_delay_slots,
 113    with the branch instruction in XEXPVEC(seq, 0, 0) and the instructions
 114    occupying the delay slots in the remaining XEXPVEC slots.
 115
 116    Another place where a SEQUENCE may appear, is in REG_FRAME_RELATED_EXPR
 117    notes, to express complex operations that are not obvious from the insn
 118    to which the REG_FRAME_RELATED_EXPR note is attached.  In this usage of
 119    SEQUENCE, the sequence vector slots do not hold real instructions but
 120    only pseudo-instructions that can be translated to DWARF CFA expressions.
 121
 122    Some back ends also use SEQUENCE to group insns in bundles.
 123
 124    Much of the compiler infrastructure is not prepared to handle SEQUENCE
 125    objects.  Only passes after pass_free_cfg are expected to handle them.  */
 126 DEF_RTL_EXPR(SEQUENCE, "sequence", "E", RTX_EXTRA)
 127
 128 /* Represents a non-global base address.  This is only used in alias.c.  */
 129 DEF_RTL_EXPR(ADDRESS, "address", "i", RTX_EXTRA)
 130
 131 /* ----------------------------------------------------------------------
 132    Expression types used for things in the instruction chain.
 133
 134    All formats must start with "iuu" to handle the chain.
 135    Each insn expression holds an rtl instruction and its semantics
 136    during back-end processing.
 137    See macros's in "rtl.h" for the meaning of each rtx->u.fld[].
 138
 139    ---------------------------------------------------------------------- */
 140
 141 /* An annotation for variable assignment tracking.  */
 142 DEF_RTL_EXPR(DEBUG_INSN, "debug_insn", "uuBeiie", RTX_INSN)
 143
 144 /* An instruction that cannot jump.  */
 145 DEF_RTL_EXPR(INSN, "insn", "uuBeiie", RTX_INSN)
 146
 147 /* An instruction that can possibly jump.
 148    Fields ( rtx->u.fld[] ) have exact same meaning as INSN's.  */
 149 DEF_RTL_EXPR(JUMP_INSN, "jump_insn", "uuBeiie0", RTX_INSN)
 150
 151 /* An instruction that can possibly call a subroutine
 152    but which will not change which instruction comes next
 153    in the current function.
 154    Field ( rtx->u.fld[8] ) is CALL_INSN_FUNCTION_USAGE.
 155    All other fields ( rtx->u.fld[] ) have exact same meaning as INSN's.  */
 156 DEF_RTL_EXPR(CALL_INSN, "call_insn", "uuBeiiee", RTX_INSN)
 157
 158 /* Placeholder for tablejump JUMP_INSNs.  The pattern of this kind
 159    of rtx is always either an ADDR_VEC or an ADDR_DIFF_VEC.  These
 160    placeholders do not appear as real instructions inside a basic
 161    block, but are considered active_insn_p instructions for historical
 162    reasons, when jump table data was represented with JUMP_INSNs.  */
 163 DEF_RTL_EXPR(JUMP_TABLE_DATA, "jump_table_data", "uuBe0000", RTX_INSN)
 164
 165 /* A marker that indicates that control will not flow through.  */
 166 DEF_RTL_EXPR(BARRIER, "barrier", "uu00000", RTX_EXTRA)
 167
 168 /* Holds a label that is followed by instructions.
 169    Operand:
 170    3: is used in jump.c for the use-count of the label.
 171    4: is used in the sh backend.
 172    5: is a number that is unique in the entire compilation.
 173    6: is the user-given name of the label, if any.  */
 174 DEF_RTL_EXPR(CODE_LABEL, "code_label", "uuB00is", RTX_EXTRA)
 175
 176 /* Say where in the code a source line starts, for symbol table's sake.
 177    Operand:
 178    3: note-specific data
 179    4: enum insn_note
 180    5: unique number if insn_note == note_insn_deleted_label.  */
 181 DEF_RTL_EXPR(NOTE, "note", "uuB0ni", RTX_EXTRA)
 182
 183 /* ----------------------------------------------------------------------
 184    Top level constituents of INSN, JUMP_INSN and CALL_INSN.
 185    ---------------------------------------------------------------------- */
 186
 187 /* Conditionally execute code.
 188    Operand 0 is the condition that if true, the code is executed.
 189    Operand 1 is the code to be executed (typically a SET).
 190
 191    Semantics are that there are no side effects if the condition
 192    is false.  This pattern is created automatically by the if_convert
 193    pass run after reload or by target-specific splitters.  */
 194 DEF_RTL_EXPR(COND_EXEC, "cond_exec", "ee", RTX_EXTRA)
 195
 196 /* Several operations to be done in parallel (perhaps under COND_EXEC).  */
 197 DEF_RTL_EXPR(PARALLEL, "parallel", "E", RTX_EXTRA)
 198
 199 /* A string that is passed through to the assembler as input.
 200      One can obviously pass comments through by using the
 201      assembler comment syntax.
 202      These occur in an insn all by themselves as the PATTERN.
 203      They also appear inside an ASM_OPERANDS
 204      as a convenient way to hold a string.  */
 205 DEF_RTL_EXPR(ASM_INPUT, "asm_input", "si", RTX_EXTRA)
 206
 207 /* An assembler instruction with operands.
 208    1st operand is the instruction template.
 209    2nd operand is the constraint for the output.
 210    3rd operand is the number of the output this expression refers to.
 211      When an insn stores more than one value, a separate ASM_OPERANDS
 212      is made for each output; this integer distinguishes them.
 213    4th is a vector of values of input operands.
 214    5th is a vector of modes and constraints for the input operands.
 215      Each element is an ASM_INPUT containing a constraint string
 216      and whose mode indicates the mode of the input operand.
 217    6th is a vector of labels that may be branched to by the asm.
 218    7th is the source line number.  */
 219 DEF_RTL_EXPR(ASM_OPERANDS, "asm_operands", "ssiEEEi", RTX_EXTRA)
 220
 221 /* A machine-specific operation.
 222    1st operand is a vector of operands being used by the operation so that
 223      any needed reloads can be done.
 224    2nd operand is a unique value saying which of a number of machine-specific
 225      operations is to be performed.
 226    (Note that the vector must be the first operand because of the way that
 227    genrecog.c record positions within an insn.)
 228
 229    UNSPEC can occur all by itself in a PATTERN, as a component of a PARALLEL,
 230    or inside an expression.
 231    UNSPEC by itself or as a component of a PARALLEL
 232    is currently considered not deletable.
 233
 234    FIXME: Replace all uses of UNSPEC that appears by itself or as a component
 235    of a PARALLEL with USE.
 236    */
 237 DEF_RTL_EXPR(UNSPEC, "unspec", "Ei", RTX_EXTRA)
 238
 239 /* Similar, but a volatile operation and one which may trap.  */
 240 DEF_RTL_EXPR(UNSPEC_VOLATILE, "unspec_volatile", "Ei", RTX_EXTRA)
 241
 242 /* ----------------------------------------------------------------------
 243    Table jump addresses.
 244    ---------------------------------------------------------------------- */
 245
 246 /* Vector of addresses, stored as full words.
 247    Each element is a LABEL_REF to a CODE_LABEL whose address we want.  */
 248 DEF_RTL_EXPR(ADDR_VEC, "addr_vec", "E", RTX_EXTRA)
 249
 250 /* Vector of address differences X0 - BASE, X1 - BASE, ...
 251    First operand is BASE; the vector contains the X's.
 252    The machine mode of this rtx says how much space to leave
 253    for each difference and is adjusted by branch shortening if
 254    CASE_VECTOR_SHORTEN_MODE is defined.
 255    The third and fourth operands store the target labels with the
 256    minimum and maximum addresses respectively.
 257    The fifth operand stores flags for use by branch shortening.
 258   Set at the start of shorten_branches:
 259    min_align: the minimum alignment for any of the target labels.
 260    base_after_vec: true iff BASE is after the ADDR_DIFF_VEC.
 261    min_after_vec: true iff minimum addr target label is after the ADDR_DIFF_VEC.
 262    max_after_vec: true iff maximum addr target label is after the ADDR_DIFF_VEC.
 263    min_after_base: true iff minimum address target label is after BASE.
 264    max_after_base: true iff maximum address target label is after BASE.
 265   Set by the actual branch shortening process:
 266    offset_unsigned: true iff offsets have to be treated as unsigned.
 267    scale: scaling that is necessary to make offsets fit into the mode.
 268
 269    The third, fourth and fifth operands are only valid when
 270    CASE_VECTOR_SHORTEN_MODE is defined, and only in an optimizing
 271    compilation.  */
 272 DEF_RTL_EXPR(ADDR_DIFF_VEC, "addr_diff_vec", "eEee0", RTX_EXTRA)
 273
 274 /* Memory prefetch, with attributes supported on some targets.
 275    Operand 1 is the address of the memory to fetch.
 276    Operand 2 is 1 for a write access, 0 otherwise.
 277    Operand 3 is the level of temporal locality; 0 means there is no
 278    temporal locality and 1, 2, and 3 are for increasing levels of temporal
 279    locality.
 280
 281    The attributes specified by operands 2 and 3 are ignored for targets
 282    whose prefetch instructions do not support them.  */
 283 DEF_RTL_EXPR(PREFETCH, "prefetch", "eee", RTX_EXTRA)
 284
 285 /* ----------------------------------------------------------------------
 286    At the top level of an instruction (perhaps under PARALLEL).
 287    ---------------------------------------------------------------------- */
 288
 289 /* Assignment.
 290    Operand 1 is the location (REG, MEM, PC, CC0 or whatever) assigned to.
 291    Operand 2 is the value stored there.
 292    ALL assignment must use SET.
 293    Instructions that do multiple assignments must use multiple SET,
 294    under PARALLEL.  */
 295 DEF_RTL_EXPR(SET, "set", "ee", RTX_EXTRA)
 296
 297 /* Indicate something is used in a way that we don't want to explain.
 298    For example, subroutine calls will use the register
 299    in which the static chain is passed.
 300
 301    USE can not appear as an operand of other rtx except for PARALLEL.
 302    USE is not deletable, as it indicates that the operand
 303    is used in some unknown way.  */
 304 DEF_RTL_EXPR(USE, "use", "e", RTX_EXTRA)
 305
 306 /* Indicate something is clobbered in a way that we don't want to explain.
 307    For example, subroutine calls will clobber some physical registers
 308    (the ones that are by convention not saved).
 309
 310    CLOBBER can not appear as an operand of other rtx except for PARALLEL.
 311    CLOBBER of a hard register appearing by itself (not within PARALLEL)
 312    is considered undeletable before reload.  */
 313 DEF_RTL_EXPR(CLOBBER, "clobber", "e", RTX_EXTRA)
 314
 315 /* Call a subroutine.
 316    Operand 1 is the address to call.
 317    Operand 2 is the number of arguments.  */
 318
 319 DEF_RTL_EXPR(CALL, "call", "ee", RTX_EXTRA)
 320
 321 /* Return from a subroutine.  */
 322
 323 DEF_RTL_EXPR(RETURN, "return", "", RTX_EXTRA)
 324
 325 /* Like RETURN, but truly represents only a function return, while
 326    RETURN may represent an insn that also performs other functions
 327    of the function epilogue.  Like RETURN, this may also occur in
 328    conditional jumps.  */
 329 DEF_RTL_EXPR(SIMPLE_RETURN, "simple_return", "", RTX_EXTRA)
 330
 331 /* Special for EH return from subroutine.  */
 332
 333 DEF_RTL_EXPR(EH_RETURN, "eh_return", "", RTX_EXTRA)
 334
 335 /* Conditional trap.
 336    Operand 1 is the condition.
 337    Operand 2 is the trap code.
 338    For an unconditional trap, make the condition (const_int 1).  */
 339 DEF_RTL_EXPR(TRAP_IF, "trap_if", "ee", RTX_EXTRA)
 340
 341 /* ----------------------------------------------------------------------
 342    Primitive values for use in expressions.
 343    ---------------------------------------------------------------------- */
 344
 345 /* numeric integer constant */
 346 DEF_RTL_EXPR(CONST_INT, "const_int", "w", RTX_CONST_OBJ)
 347
 348 /* numeric integer constant */
 349 DEF_RTL_EXPR(CONST_WIDE_INT, "const_wide_int", "", RTX_CONST_OBJ)
 350
 351 /* fixed-point constant */
 352 DEF_RTL_EXPR(CONST_FIXED, "const_fixed", "www", RTX_CONST_OBJ)
 353
 354 /* numeric floating point or integer constant.  If the mode is
 355    VOIDmode it is an int otherwise it has a floating point mode and a
 356    floating point value.  Operands hold the value.  They are all 'w'
 357    and there may be from 2 to 6; see real.h.  */
 358 DEF_RTL_EXPR(CONST_DOUBLE, "const_double", CONST_DOUBLE_FORMAT, RTX_CONST_OBJ)
 359
 360 /* Describes a vector constant.  */
 361 DEF_RTL_EXPR(CONST_VECTOR, "const_vector", "E", RTX_CONST_OBJ)
 362
 363 /* String constant.  Used for attributes in machine descriptions and
 364    for special cases in DWARF2 debug output.  NOT used for source-
 365    language string constants.  */
 366 DEF_RTL_EXPR(CONST_STRING, "const_string", "s", RTX_OBJ)
 367
 368 /* This is used to encapsulate an expression whose value is constant
 369    (such as the sum of a SYMBOL_REF and a CONST_INT) so that it will be
 370    recognized as a constant operand rather than by arithmetic instructions.  */
 371
 372 DEF_RTL_EXPR(CONST, "const", "e", RTX_CONST_OBJ)
 373
 374 /* program counter.  Ordinary jumps are represented
 375    by a SET whose first operand is (PC).  */
 376 DEF_RTL_EXPR(PC, "pc", "", RTX_OBJ)
 377
 378 /* A register.  The "operand" is the register number, accessed with
 379    the REGNO macro.  If this number is less than FIRST_PSEUDO_REGISTER
 380    than a hardware register is being referred to.  The second operand
 381    points to a reg_attrs structure.
 382    This rtx needs to have as many (or more) fields as a MEM, since we
 383    can change REG rtx's into MEMs during reload.  */
 384 DEF_RTL_EXPR(REG, "reg", "i0", RTX_OBJ)
 385
 386 /* A scratch register.  This represents a register used only within a
 387    single insn.  It will be replaced by a REG during register allocation
 388    or reload unless the constraint indicates that the register won't be
 389    needed, in which case it can remain a SCRATCH.  */
 390 DEF_RTL_EXPR(SCRATCH, "scratch", "", RTX_OBJ)
 391
 392 /* A reference to a part of another value.  The first operand is the
 393    complete value and the second is the byte offset of the selected part.   */
 394 DEF_RTL_EXPR(SUBREG, "subreg", "ei", RTX_EXTRA)
 395
 396 /* This one-argument rtx is used for move instructions
 397    that are guaranteed to alter only the low part of a destination.
 398    Thus, (SET (SUBREG:HI (REG...)) (MEM:HI ...))
 399    has an unspecified effect on the high part of REG,
 400    but (SET (STRICT_LOW_PART (SUBREG:HI (REG...))) (MEM:HI ...))
 401    is guaranteed to alter only the bits of REG that are in HImode.
 402
 403    The actual instruction used is probably the same in both cases,
 404    but the register constraints may be tighter when STRICT_LOW_PART
 405    is in use.  */
 406
 407 DEF_RTL_EXPR(STRICT_LOW_PART, "strict_low_part", "e", RTX_EXTRA)
 408
 409 /* (CONCAT a b) represents the virtual concatenation of a and b
 410    to make a value that has as many bits as a and b put together.
 411    This is used for complex values.  Normally it appears only
 412    in DECL_RTLs and during RTL generation, but not in the insn chain.  */
 413 DEF_RTL_EXPR(CONCAT, "concat", "ee", RTX_OBJ)
 414
 415 /* (CONCATN [a1 a2 ... an]) represents the virtual concatenation of
 416    all An to make a value.  This is an extension of CONCAT to larger
 417    number of components.  Like CONCAT, it should not appear in the
 418    insn chain.  Every element of the CONCATN is the same size.  */
 419 DEF_RTL_EXPR(CONCATN, "concatn", "E", RTX_OBJ)
 420
 421 /* A memory location; operand is the address.  The second operand is the
 422    alias set to which this MEM belongs.  We use `0' instead of `w' for this
 423    field so that the field need not be specified in machine descriptions.  */
 424 DEF_RTL_EXPR(MEM, "mem", "e0", RTX_OBJ)
 425
 426 /* Reference to an assembler label in the code for this function.
 427    The operand is a CODE_LABEL found in the insn chain.  */
 428 DEF_RTL_EXPR(LABEL_REF, "label_ref", "u", RTX_CONST_OBJ)
 429
 430 /* Reference to a named label:
 431    Operand 0: label name
 432    Operand 1: tree from which this symbol is derived, or null.
 433    This is either a DECL node, or some kind of constant.  */
 434 DEF_RTL_EXPR(SYMBOL_REF, "symbol_ref", "s0", RTX_CONST_OBJ)
 435
 436 /* The condition code register is represented, in our imagination,
 437    as a register holding a value that can be compared to zero.
 438    In fact, the machine has already compared them and recorded the
 439    results; but instructions that look at the condition code
 440    pretend to be looking at the entire value and comparing it.  */
 441 DEF_RTL_EXPR(CC0, "cc0", "", RTX_OBJ)
 442
 443 /* ----------------------------------------------------------------------
 444    Expressions for operators in an rtl pattern
 445    ---------------------------------------------------------------------- */
 446
 447 /* if_then_else.  This is used in representing ordinary
 448    conditional jump instructions.
 449      Operand:
 450      0:  condition
 451      1:  then expr
 452      2:  else expr */
 453 DEF_RTL_EXPR(IF_THEN_ELSE, "if_then_else", "eee", RTX_TERNARY)
 454
 455 /* Comparison, produces a condition code result.  */
 456 DEF_RTL_EXPR(COMPARE, "compare", "ee", RTX_BIN_ARITH)
 457
 458 /* plus */
 459 DEF_RTL_EXPR(PLUS, "plus", "ee", RTX_COMM_ARITH)
 460
 461 /* Operand 0 minus operand 1.  */
 462 DEF_RTL_EXPR(MINUS, "minus", "ee", RTX_BIN_ARITH)
 463
 464 /* Minus operand 0.  */
 465 DEF_RTL_EXPR(NEG, "neg", "e", RTX_UNARY)
 466
 467 DEF_RTL_EXPR(MULT, "mult", "ee", RTX_COMM_ARITH)
 468
 469 /* Multiplication with signed saturation */
 470 DEF_RTL_EXPR(SS_MULT, "ss_mult", "ee", RTX_COMM_ARITH)
 471 /* Multiplication with unsigned saturation */
 472 DEF_RTL_EXPR(US_MULT, "us_mult", "ee", RTX_COMM_ARITH)
 473
 474 /* Operand 0 divided by operand 1.  */
 475 DEF_RTL_EXPR(DIV, "div", "ee", RTX_BIN_ARITH)
 476 /* Division with signed saturation */
 477 DEF_RTL_EXPR(SS_DIV, "ss_div", "ee", RTX_BIN_ARITH)
 478 /* Division with unsigned saturation */
 479 DEF_RTL_EXPR(US_DIV, "us_div", "ee", RTX_BIN_ARITH)
 480
 481 /* Remainder of operand 0 divided by operand 1.  */
 482 DEF_RTL_EXPR(MOD, "mod", "ee", RTX_BIN_ARITH)
 483
 484 /* Unsigned divide and remainder.  */
 485 DEF_RTL_EXPR(UDIV, "udiv", "ee", RTX_BIN_ARITH)
 486 DEF_RTL_EXPR(UMOD, "umod", "ee", RTX_BIN_ARITH)
 487
 488 /* Bitwise operations.  */
 489 DEF_RTL_EXPR(AND, "and", "ee", RTX_COMM_ARITH)
 490 DEF_RTL_EXPR(IOR, "ior", "ee", RTX_COMM_ARITH)
 491 DEF_RTL_EXPR(XOR, "xor", "ee", RTX_COMM_ARITH)
 492 DEF_RTL_EXPR(NOT, "not", "e", RTX_UNARY)
 493
 494 /* Operand:
 495      0:  value to be shifted.
 496      1:  number of bits.  */
 497 DEF_RTL_EXPR(ASHIFT, "ashift", "ee", RTX_BIN_ARITH) /* shift left */
 498 DEF_RTL_EXPR(ROTATE, "rotate", "ee", RTX_BIN_ARITH) /* rotate left */
 499 DEF_RTL_EXPR(ASHIFTRT, "ashiftrt", "ee", RTX_BIN_ARITH) /* arithmetic shift right */
 500 DEF_RTL_EXPR(LSHIFTRT, "lshiftrt", "ee", RTX_BIN_ARITH) /* logical shift right */
 501 DEF_RTL_EXPR(ROTATERT, "rotatert", "ee", RTX_BIN_ARITH) /* rotate right */
 502
 503 /* Minimum and maximum values of two operands.  We need both signed and
 504    unsigned forms.  (We cannot use MIN for SMIN because it conflicts
 505    with a macro of the same name.)   The signed variants should be used
 506    with floating point.  Further, if both operands are zeros, or if either
 507    operand is NaN, then it is unspecified which of the two operands is
 508    returned as the result.  */
 509
 510 DEF_RTL_EXPR(SMIN, "smin", "ee", RTX_COMM_ARITH)
 511 DEF_RTL_EXPR(SMAX, "smax", "ee", RTX_COMM_ARITH)
 512 DEF_RTL_EXPR(UMIN, "umin", "ee", RTX_COMM_ARITH)
 513 DEF_RTL_EXPR(UMAX, "umax", "ee", RTX_COMM_ARITH)
 514
 515 /* These unary operations are used to represent incrementation
 516    and decrementation as they occur in memory addresses.
 517    The amount of increment or decrement are not represented
 518    because they can be understood from the machine-mode of the
 519    containing MEM.  These operations exist in only two cases:
 520    1. pushes onto the stack.
 521    2. created automatically by the auto-inc-dec pass.  */
 522 DEF_RTL_EXPR(PRE_DEC, "pre_dec", "e", RTX_AUTOINC)
 523 DEF_RTL_EXPR(PRE_INC, "pre_inc", "e", RTX_AUTOINC)
 524 DEF_RTL_EXPR(POST_DEC, "post_dec", "e", RTX_AUTOINC)
 525 DEF_RTL_EXPR(POST_INC, "post_inc", "e", RTX_AUTOINC)
 526
 527 /* These binary operations are used to represent generic address
 528    side-effects in memory addresses, except for simple incrementation
 529    or decrementation which use the above operations.  They are
 530    created automatically by the life_analysis pass in flow.c.
 531    The first operand is a REG which is used as the address.
 532    The second operand is an expression that is assigned to the
 533    register, either before (PRE_MODIFY) or after (POST_MODIFY)
 534    evaluating the address.
 535    Currently, the compiler can only handle second operands of the
 536    form (plus (reg) (reg)) and (plus (reg) (const_int)), where
 537    the first operand of the PLUS has to be the same register as
 538    the first operand of the *_MODIFY.  */
 539 DEF_RTL_EXPR(PRE_MODIFY, "pre_modify", "ee", RTX_AUTOINC)
 540 DEF_RTL_EXPR(POST_MODIFY, "post_modify", "ee", RTX_AUTOINC)
 541
 542 /* Comparison operations.  The ordered comparisons exist in two
 543    flavors, signed and unsigned.  */
 544 DEF_RTL_EXPR(NE, "ne", "ee", RTX_COMM_COMPARE)
 545 DEF_RTL_EXPR(EQ, "eq", "ee", RTX_COMM_COMPARE)
 546 DEF_RTL_EXPR(GE, "ge", "ee", RTX_COMPARE)
 547 DEF_RTL_EXPR(GT, "gt", "ee", RTX_COMPARE)
 548 DEF_RTL_EXPR(LE, "le", "ee", RTX_COMPARE)
 549 DEF_RTL_EXPR(LT, "lt", "ee", RTX_COMPARE)
 550 DEF_RTL_EXPR(GEU, "geu", "ee", RTX_COMPARE)
 551 DEF_RTL_EXPR(GTU, "gtu", "ee", RTX_COMPARE)
 552 DEF_RTL_EXPR(LEU, "leu", "ee", RTX_COMPARE)
 553 DEF_RTL_EXPR(LTU, "ltu", "ee", RTX_COMPARE)
 554
 555 /* Additional floating point unordered comparison flavors.  */
 556 DEF_RTL_EXPR(UNORDERED, "unordered", "ee", RTX_COMM_COMPARE)
 557 DEF_RTL_EXPR(ORDERED, "ordered", "ee", RTX_COMM_COMPARE)
 558
 559 /* These are equivalent to unordered or ...  */
 560 DEF_RTL_EXPR(UNEQ, "uneq", "ee", RTX_COMM_COMPARE)
 561 DEF_RTL_EXPR(UNGE, "unge", "ee", RTX_COMPARE)
 562 DEF_RTL_EXPR(UNGT, "ungt", "ee", RTX_COMPARE)
 563 DEF_RTL_EXPR(UNLE, "unle", "ee", RTX_COMPARE)
 564 DEF_RTL_EXPR(UNLT, "unlt", "ee", RTX_COMPARE)
 565
 566 /* This is an ordered NE, ie !UNEQ, ie false for NaN.  */
 567 DEF_RTL_EXPR(LTGT, "ltgt", "ee", RTX_COMM_COMPARE)
 568
 569 /* Represents the result of sign-extending the sole operand.
 570    The machine modes of the operand and of the SIGN_EXTEND expression
 571    determine how much sign-extension is going on.  */
 572 DEF_RTL_EXPR(SIGN_EXTEND, "sign_extend", "e", RTX_UNARY)
 573
 574 /* Similar for zero-extension (such as unsigned short to int).  */
 575 DEF_RTL_EXPR(ZERO_EXTEND, "zero_extend", "e", RTX_UNARY)
 576
 577 /* Similar but here the operand has a wider mode.  */
 578 DEF_RTL_EXPR(TRUNCATE, "truncate", "e", RTX_UNARY)
 579
 580 /* Similar for extending floating-point values (such as SFmode to DFmode).  */
 581 DEF_RTL_EXPR(FLOAT_EXTEND, "float_extend", "e", RTX_UNARY)
 582 DEF_RTL_EXPR(FLOAT_TRUNCATE, "float_truncate", "e", RTX_UNARY)
 583
 584 /* Conversion of fixed point operand to floating point value.  */
 585 DEF_RTL_EXPR(FLOAT, "float", "e", RTX_UNARY)
 586
 587 /* With fixed-point machine mode:
 588    Conversion of floating point operand to fixed point value.
 589    Value is defined only when the operand's value is an integer.
 590    With floating-point machine mode (and operand with same mode):
 591    Operand is rounded toward zero to produce an integer value
 592    represented in floating point.  */
 593 DEF_RTL_EXPR(FIX, "fix", "e", RTX_UNARY)
 594
 595 /* Conversion of unsigned fixed point operand to floating point value.  */
 596 DEF_RTL_EXPR(UNSIGNED_FLOAT, "unsigned_float", "e", RTX_UNARY)
 597
 598 /* With fixed-point machine mode:
 599    Conversion of floating point operand to *unsigned* fixed point value.
 600    Value is defined only when the operand's value is an integer.  */
 601 DEF_RTL_EXPR(UNSIGNED_FIX, "unsigned_fix", "e", RTX_UNARY)
 602
 603 /* Conversions involving fractional fixed-point types without saturation,
 604    including:
 605      fractional to fractional (of different precision),
 606      signed integer to fractional,
 607      fractional to signed integer,
 608      floating point to fractional,
 609      fractional to floating point.
 610    NOTE: fractional can be either signed or unsigned for conversions.  */
 611 DEF_RTL_EXPR(FRACT_CONVERT, "fract_convert", "e", RTX_UNARY)
 612
 613 /* Conversions involving fractional fixed-point types and unsigned integer
 614    without saturation, including:
 615      unsigned integer to fractional,
 616      fractional to unsigned integer.
 617    NOTE: fractional can be either signed or unsigned for conversions.  */
 618 DEF_RTL_EXPR(UNSIGNED_FRACT_CONVERT, "unsigned_fract_convert", "e", RTX_UNARY)
 619
 620 /* Conversions involving fractional fixed-point types with saturation,
 621    including:
 622      fractional to fractional (of different precision),
 623      signed integer to fractional,
 624      floating point to fractional.
 625    NOTE: fractional can be either signed or unsigned for conversions.  */
 626 DEF_RTL_EXPR(SAT_FRACT, "sat_fract", "e", RTX_UNARY)
 627
 628 /* Conversions involving fractional fixed-point types and unsigned integer
 629    with saturation, including:
 630      unsigned integer to fractional.
 631    NOTE: fractional can be either signed or unsigned for conversions.  */
 632 DEF_RTL_EXPR(UNSIGNED_SAT_FRACT, "unsigned_sat_fract", "e", RTX_UNARY)
 633
 634 /* Absolute value */
 635 DEF_RTL_EXPR(ABS, "abs", "e", RTX_UNARY)
 636
 637 /* Square root */
 638 DEF_RTL_EXPR(SQRT, "sqrt", "e", RTX_UNARY)
 639
 640 /* Swap bytes.  */
 641 DEF_RTL_EXPR(BSWAP, "bswap", "e", RTX_UNARY)
 642
 643 /* Find first bit that is set.
 644    Value is 1 + number of trailing zeros in the arg.,
 645    or 0 if arg is 0.  */
 646 DEF_RTL_EXPR(FFS, "ffs", "e", RTX_UNARY)
 647
 648 /* Count number of leading redundant sign bits (number of leading
 649    sign bits minus one).  */
 650 DEF_RTL_EXPR(CLRSB, "clrsb", "e", RTX_UNARY)
 651
 652 /* Count leading zeros.  */
 653 DEF_RTL_EXPR(CLZ, "clz", "e", RTX_UNARY)
 654
 655 /* Count trailing zeros.  */
 656 DEF_RTL_EXPR(CTZ, "ctz", "e", RTX_UNARY)
 657
 658 /* Population count (number of 1 bits).  */
 659 DEF_RTL_EXPR(POPCOUNT, "popcount", "e", RTX_UNARY)
 660
 661 /* Population parity (number of 1 bits modulo 2).  */
 662 DEF_RTL_EXPR(PARITY, "parity", "e", RTX_UNARY)
 663
 664 /* Reference to a signed bit-field of specified size and position.
 665    Operand 0 is the memory unit (usually SImode or QImode) which
 666    contains the field's first bit.  Operand 1 is the width, in bits.
 667    Operand 2 is the number of bits in the memory unit before the
 668    first bit of this field.
 669    If BITS_BIG_ENDIAN is defined, the first bit is the msb and
 670    operand 2 counts from the msb of the memory unit.
 671    Otherwise, the first bit is the lsb and operand 2 counts from
 672    the lsb of the memory unit.
 673    This kind of expression can not appear as an lvalue in RTL.  */
 674 DEF_RTL_EXPR(SIGN_EXTRACT, "sign_extract", "eee", RTX_BITFIELD_OPS)
 675
 676 /* Similar for unsigned bit-field.
 677    But note!  This kind of expression _can_ appear as an lvalue.  */
 678 DEF_RTL_EXPR(ZERO_EXTRACT, "zero_extract", "eee", RTX_BITFIELD_OPS)
 679
 680 /* For RISC machines.  These save memory when splitting insns.  */
 681
 682 /* HIGH are the high-order bits of a constant expression.  */
 683 DEF_RTL_EXPR(HIGH, "high", "e", RTX_CONST_OBJ)
 684
 685 /* LO_SUM is the sum of a register and the low-order bits
 686    of a constant expression.  */
 687 DEF_RTL_EXPR(LO_SUM, "lo_sum", "ee", RTX_OBJ)
 688
 689 /* Describes a merge operation between two vector values.
 690    Operands 0 and 1 are the vectors to be merged, operand 2 is a bitmask
 691    that specifies where the parts of the result are taken from.  Set bits
 692    indicate operand 0, clear bits indicate operand 1.  The parts are defined
 693    by the mode of the vectors.  */
 694 DEF_RTL_EXPR(VEC_MERGE, "vec_merge", "eee", RTX_TERNARY)
 695
 696 /* Describes an operation that selects parts of a vector.
 697    Operands 0 is the source vector, operand 1 is a PARALLEL that contains
 698    a CONST_INT for each of the subparts of the result vector, giving the
 699    number of the source subpart that should be stored into it.  */
 700 DEF_RTL_EXPR(VEC_SELECT, "vec_select", "ee", RTX_BIN_ARITH)
 701
 702 /* Describes a vector concat operation.  Operands 0 and 1 are the source
 703    vectors, the result is a vector that is as long as operands 0 and 1
 704    combined and is the concatenation of the two source vectors.  */
 705 DEF_RTL_EXPR(VEC_CONCAT, "vec_concat", "ee", RTX_BIN_ARITH)
 706
 707 /* Describes an operation that converts a small vector into a larger one by
 708    duplicating the input values.  The output vector mode must have the same
 709    submodes as the input vector mode, and the number of output parts must be
 710    an integer multiple of the number of input parts.  */
 711 DEF_RTL_EXPR(VEC_DUPLICATE, "vec_duplicate", "e", RTX_UNARY)
 712
 713 /* Addition with signed saturation */
 714 DEF_RTL_EXPR(SS_PLUS, "ss_plus", "ee", RTX_COMM_ARITH)
 715
 716 /* Addition with unsigned saturation */
 717 DEF_RTL_EXPR(US_PLUS, "us_plus", "ee", RTX_COMM_ARITH)
 718
 719 /* Operand 0 minus operand 1, with signed saturation.  */
 720 DEF_RTL_EXPR(SS_MINUS, "ss_minus", "ee", RTX_BIN_ARITH)
 721
 722 /* Negation with signed saturation.  */
 723 DEF_RTL_EXPR(SS_NEG, "ss_neg", "e", RTX_UNARY)
 724 /* Negation with unsigned saturation.  */
 725 DEF_RTL_EXPR(US_NEG, "us_neg", "e", RTX_UNARY)
 726
 727 /* Absolute value with signed saturation.  */
 728 DEF_RTL_EXPR(SS_ABS, "ss_abs", "e", RTX_UNARY)
 729
 730 /* Shift left with signed saturation.  */
 731 DEF_RTL_EXPR(SS_ASHIFT, "ss_ashift", "ee", RTX_BIN_ARITH)
 732
 733 /* Shift left with unsigned saturation.  */
 734 DEF_RTL_EXPR(US_ASHIFT, "us_ashift", "ee", RTX_BIN_ARITH)
 735
 736 /* Operand 0 minus operand 1, with unsigned saturation.  */
 737 DEF_RTL_EXPR(US_MINUS, "us_minus", "ee", RTX_BIN_ARITH)
 738
 739 /* Signed saturating truncate.  */
 740 DEF_RTL_EXPR(SS_TRUNCATE, "ss_truncate", "e", RTX_UNARY)
 741
 742 /* Unsigned saturating truncate.  */
 743 DEF_RTL_EXPR(US_TRUNCATE, "us_truncate", "e", RTX_UNARY)
 744
 745 /* Floating point multiply/add combined instruction.  */
 746 DEF_RTL_EXPR(FMA, "fma", "eee", RTX_TERNARY)
 747
 748 /* Information about the variable and its location.  */
 749 DEF_RTL_EXPR(VAR_LOCATION, "var_location", "te", RTX_EXTRA)
 750
 751 /* Used in VAR_LOCATION for a pointer to a decl that is no longer
 752    addressable.  */
 753 DEF_RTL_EXPR(DEBUG_IMPLICIT_PTR, "debug_implicit_ptr", "t", RTX_OBJ)
 754
 755 /* Represents value that argument had on function entry.  The
 756    single argument is the DECL_INCOMING_RTL of the corresponding
 757    parameter.  */
 758 DEF_RTL_EXPR(ENTRY_VALUE, "entry_value", "0", RTX_OBJ)
 759
 760 /* Used in VAR_LOCATION for a reference to a parameter that has
 761    been optimized away completely.  */
 762 DEF_RTL_EXPR(DEBUG_PARAMETER_REF, "debug_parameter_ref", "t", RTX_OBJ)
 763
 764 /* All expressions from this point forward appear only in machine
 765    descriptions.  */
 766 #ifdef GENERATOR_FILE
 767
 768 /* Pattern-matching operators:  */
 769
 770 /* Use the function named by the second arg (the string)
 771    as a predicate; if matched, store the structure that was matched
 772    in the operand table at index specified by the first arg (the integer).
 773    If the second arg is the null string, the structure is just stored.
 774
 775    A third string argument indicates to the register allocator restrictions
 776    on where the operand can be allocated.
 777
 778    If the target needs no restriction on any instruction this field should
 779    be the null string.
 780
 781    The string is prepended by:
 782    '=' to indicate the operand is only written to.
 783    '+' to indicate the operand is both read and written to.
 784
 785    Each character in the string represents an allocable class for an operand.
 786    'g' indicates the operand can be any valid class.
 787    'i' indicates the operand can be immediate (in the instruction) data.
 788    'r' indicates the operand can be in a register.
 789    'm' indicates the operand can be in memory.
 790    'o' a subset of the 'm' class.  Those memory addressing modes that
 791        can be offset at compile time (have a constant added to them).
 792
 793    Other characters indicate target dependent operand classes and
 794    are described in each target's machine description.
 795
 796    For instructions with more than one operand, sets of classes can be
 797    separated by a comma to indicate the appropriate multi-operand constraints.
 798    There must be a 1 to 1 correspondence between these sets of classes in
 799    all operands for an instruction.
 800    */
 801 DEF_RTL_EXPR(MATCH_OPERAND, "match_operand", "iss", RTX_MATCH)
 802
 803 /* Match a SCRATCH or a register.  When used to generate rtl, a
 804    SCRATCH is generated.  As for MATCH_OPERAND, the mode specifies
 805    the desired mode and the first argument is the operand number.
 806    The second argument is the constraint.  */
 807 DEF_RTL_EXPR(MATCH_SCRATCH, "match_scratch", "is", RTX_MATCH)
 808
 809 /* Apply a predicate, AND match recursively the operands of the rtx.
 810    Operand 0 is the operand-number, as in match_operand.
 811    Operand 1 is a predicate to apply (as a string, a function name).
 812    Operand 2 is a vector of expressions, each of which must match
 813    one subexpression of the rtx this construct is matching.  */
 814 DEF_RTL_EXPR(MATCH_OPERATOR, "match_operator", "isE", RTX_MATCH)
 815
 816 /* Match a PARALLEL of arbitrary length.  The predicate is applied
 817    to the PARALLEL and the initial expressions in the PARALLEL are matched.
 818    Operand 0 is the operand-number, as in match_operand.
 819    Operand 1 is a predicate to apply to the PARALLEL.
 820    Operand 2 is a vector of expressions, each of which must match the
 821    corresponding element in the PARALLEL.  */
 822 DEF_RTL_EXPR(MATCH_PARALLEL, "match_parallel", "isE", RTX_MATCH)
 823
 824 /* Match only something equal to what is stored in the operand table
 825    at the index specified by the argument.  Use with MATCH_OPERAND.  */
 826 DEF_RTL_EXPR(MATCH_DUP, "match_dup", "i", RTX_MATCH)
 827
 828 /* Match only something equal to what is stored in the operand table
 829    at the index specified by the argument.  Use with MATCH_OPERATOR.  */
 830 DEF_RTL_EXPR(MATCH_OP_DUP, "match_op_dup", "iE", RTX_MATCH)
 831
 832 /* Match only something equal to what is stored in the operand table
 833    at the index specified by the argument.  Use with MATCH_PARALLEL.  */
 834 DEF_RTL_EXPR(MATCH_PAR_DUP, "match_par_dup", "iE", RTX_MATCH)
 835
 836 /* Appears only in define_predicate/define_special_predicate
 837    expressions.  Evaluates true only if the operand has an RTX code
 838    from the set given by the argument (a comma-separated list).  If the
 839    second argument is present and nonempty, it is a sequence of digits
 840    and/or letters which indicates the subexpression to test, using the
 841    same syntax as genextract/genrecog's location strings: 0-9 for
 842    XEXP (op, n), a-z for XVECEXP (op, 0, n); each character applies to
 843    the result of the one before it.  */
 844 DEF_RTL_EXPR(MATCH_CODE, "match_code", "ss", RTX_MATCH)
 845
 846 /* Used to inject a C conditional expression into an .md file.  It can
 847    appear in a predicate definition or an attribute expression.  */
 848 DEF_RTL_EXPR(MATCH_TEST, "match_test", "s", RTX_MATCH)
 849
 850 /* Insn (and related) definitions.  */
 851
 852 /* Definition of the pattern for one kind of instruction.
 853    Operand:
 854    0: names this instruction.
 855       If the name is the null string, the instruction is in the
 856       machine description just to be recognized, and will never be emitted by
 857       the tree to rtl expander.
 858    1: is the pattern.
 859    2: is a string which is a C expression
 860       giving an additional condition for recognizing this pattern.
 861       A null string means no extra condition.
 862    3: is the action to execute if this pattern is matched.
 863       If this assembler code template starts with a * then it is a fragment of
 864       C code to run to decide on a template to use.  Otherwise, it is the
 865       template to use.
 866    4: optionally, a vector of attributes for this insn.
 867      */
 868 DEF_RTL_EXPR(DEFINE_INSN, "define_insn", "sEsTV", RTX_EXTRA)
 869
 870 /* Definition of a peephole optimization.
 871    1st operand: vector of insn patterns to match
 872    2nd operand: C expression that must be true
 873    3rd operand: template or C code to produce assembler output.
 874    4: optionally, a vector of attributes for this insn.
 875
 876    This form is deprecated; use define_peephole2 instead.  */
 877 DEF_RTL_EXPR(DEFINE_PEEPHOLE, "define_peephole", "EsTV", RTX_EXTRA)
 878
 879 /* Definition of a split operation.
 880    1st operand: insn pattern to match
 881    2nd operand: C expression that must be true
 882    3rd operand: vector of insn patterns to place into a SEQUENCE
 883    4th operand: optionally, some C code to execute before generating the
 884         insns.  This might, for example, create some RTX's and store them in
 885         elements of `recog_data.operand' for use by the vector of
 886         insn-patterns.
 887         (`operands' is an alias here for `recog_data.operand').  */
 888 DEF_RTL_EXPR(DEFINE_SPLIT, "define_split", "EsES", RTX_EXTRA)
 889
 890 /* Definition of an insn and associated split.
 891    This is the concatenation, with a few modifications, of a define_insn
 892    and a define_split which share the same pattern.
 893    Operand:
 894    0: names this instruction.
 895       If the name is the null string, the instruction is in the
 896       machine description just to be recognized, and will never be emitted by
 897       the tree to rtl expander.
 898    1: is the pattern.
 899    2: is a string which is a C expression
 900       giving an additional condition for recognizing this pattern.
 901       A null string means no extra condition.
 902    3: is the action to execute if this pattern is matched.
 903       If this assembler code template starts with a * then it is a fragment of
 904       C code to run to decide on a template to use.  Otherwise, it is the
 905       template to use.
 906    4: C expression that must be true for split.  This may start with "&&"
 907       in which case the split condition is the logical and of the insn
 908       condition and what follows the "&&" of this operand.
 909    5: vector of insn patterns to place into a SEQUENCE
 910    6: optionally, some C code to execute before generating the
 911         insns.  This might, for example, create some RTX's and store them in
 912         elements of `recog_data.operand' for use by the vector of
 913         insn-patterns.
 914         (`operands' is an alias here for `recog_data.operand').
 915    7: optionally, a vector of attributes for this insn.  */
 916 DEF_RTL_EXPR(DEFINE_INSN_AND_SPLIT, "define_insn_and_split", "sEsTsESV", RTX_EXTRA)
 917
 918 /* Definition of an RTL peephole operation.
 919    Follows the same arguments as define_split.  */
 920 DEF_RTL_EXPR(DEFINE_PEEPHOLE2, "define_peephole2", "EsES", RTX_EXTRA)
 921
 922 /* Define how to generate multiple insns for a standard insn name.
 923    1st operand: the insn name.
 924    2nd operand: vector of insn-patterns.
 925         Use match_operand to substitute an element of `recog_data.operand'.
 926    3rd operand: C expression that must be true for this to be available.
 927         This may not test any operands.
 928    4th operand: Extra C code to execute before generating the insns.
 929         This might, for example, create some RTX's and store them in
 930         elements of `recog_data.operand' for use by the vector of
 931         insn-patterns.
 932         (`operands' is an alias here for `recog_data.operand').
 933    5th: optionally, a vector of attributes for this expand.  */
 934 DEF_RTL_EXPR(DEFINE_EXPAND, "define_expand", "sEssV", RTX_EXTRA)
 935
 936 /* Define a requirement for delay slots.
 937    1st operand: Condition involving insn attributes that, if true,
 938                 indicates that the insn requires the number of delay slots
 939                 shown.
 940    2nd operand: Vector whose length is the three times the number of delay
 941                 slots required.
 942                 Each entry gives three conditions, each involving attributes.
 943                 The first must be true for an insn to occupy that delay slot
 944                 location.  The second is true for all insns that can be
 945                 annulled if the branch is true and the third is true for all
 946                 insns that can be annulled if the branch is false.
 947
 948    Multiple DEFINE_DELAYs may be present.  They indicate differing
 949    requirements for delay slots.  */
 950 DEF_RTL_EXPR(DEFINE_DELAY, "define_delay", "eE", RTX_EXTRA)
 951
 952 /* Define attribute computation for `asm' instructions.  */
 953 DEF_RTL_EXPR(DEFINE_ASM_ATTRIBUTES, "define_asm_attributes", "V", RTX_EXTRA)
 954
 955 /* Definition of a conditional execution meta operation.  Automatically
 956    generates new instances of DEFINE_INSN, selected by having attribute
 957    "predicable" true.  The new pattern will contain a COND_EXEC and the
 958    predicate at top-level.
 959
 960    Operand:
 961    0: The predicate pattern.  The top-level form should match a
 962       relational operator.  Operands should have only one alternative.
 963    1: A C expression giving an additional condition for recognizing
 964       the generated pattern.
 965    2: A template or C code to produce assembler output.
 966    3: A vector of attributes to append to the resulting cond_exec insn.  */
 967 DEF_RTL_EXPR(DEFINE_COND_EXEC, "define_cond_exec", "EssV", RTX_EXTRA)
 968
 969 /* Definition of an operand predicate.  The difference between
 970    DEFINE_PREDICATE and DEFINE_SPECIAL_PREDICATE is that genrecog will
 971    not warn about a match_operand with no mode if it has a predicate
 972    defined with DEFINE_SPECIAL_PREDICATE.
 973
 974    Operand:
 975    0: The name of the predicate.
 976    1: A boolean expression which computes whether or not the predicate
 977       matches.  This expression can use IOR, AND, NOT, MATCH_OPERAND,
 978       MATCH_CODE, and MATCH_TEST.  It must be specific enough that genrecog
 979       can calculate the set of RTX codes that can possibly match.
 980    2: A C function body which must return true for the predicate to match.
 981       Optional.  Use this when the test is too complicated to fit into a
 982       match_test expression.  */
 983 DEF_RTL_EXPR(DEFINE_PREDICATE, "define_predicate", "ses", RTX_EXTRA)
 984 DEF_RTL_EXPR(DEFINE_SPECIAL_PREDICATE, "define_special_predicate", "ses", RTX_EXTRA)
 985
 986 /* Definition of a register operand constraint.  This simply maps the
 987    constraint string to a register class.
 988
 989    Operand:
 990    0: The name of the constraint (often, but not always, a single letter).
 991    1: A C expression which evaluates to the appropriate register class for
 992       this constraint.  If this is not just a constant, it should look only
 993       at -m switches and the like.
 994    2: A docstring for this constraint, in Texinfo syntax; not currently
 995       used, in future will be incorporated into the manual's list of
 996       machine-specific operand constraints.  */
 997 DEF_RTL_EXPR(DEFINE_REGISTER_CONSTRAINT, "define_register_constraint", "sss", RTX_EXTRA)
 998
 999 /* Definition of a non-register operand constraint.  These look at the
1000    operand and decide whether it fits the constraint.
1001
1002    DEFINE_CONSTRAINT gets no special treatment if it fails to match.
1003    It is appropriate for constant-only constraints, and most others.
1004
1005    DEFINE_MEMORY_CONSTRAINT tells reload that this constraint can be made
1006    to match, if it doesn't already, by converting the operand to the form
1007    (mem (reg X)) where X is a base register.  It is suitable for constraints
1008    that describe a subset of all memory references.
1009
1010    DEFINE_ADDRESS_CONSTRAINT tells reload that this constraint can be made
1011    to match, if it doesn't already, by converting the operand to the form
1012    (reg X) where X is a base register.  It is suitable for constraints that
1013    describe a subset of all address references.
1014
1015    When in doubt, use plain DEFINE_CONSTRAINT.
1016
1017    Operand:
1018    0: The name of the constraint (often, but not always, a single letter).
1019    1: A docstring for this constraint, in Texinfo syntax; not currently
1020       used, in future will be incorporated into the manual's list of
1021       machine-specific operand constraints.
1022    2: A boolean expression which computes whether or not the constraint
1023       matches.  It should follow the same rules as a define_predicate
1024       expression, including the bit about specifying the set of RTX codes
1025       that could possibly match.  MATCH_TEST subexpressions may make use of
1026       these variables:
1027         `op'    - the RTL object defining the operand.
1028         `mode'  - the mode of `op'.
1029         `ival'  - INTVAL(op), if op is a CONST_INT.
1030         `hval'  - CONST_DOUBLE_HIGH(op), if op is an integer CONST_DOUBLE.
1031         `lval'  - CONST_DOUBLE_LOW(op), if op is an integer CONST_DOUBLE.
1032         `rval'  - CONST_DOUBLE_REAL_VALUE(op), if op is a floating-point
1033                   CONST_DOUBLE.
1034       Do not use ival/hval/lval/rval if op is not the appropriate kind of
1035       RTL object.  */
1036 DEF_RTL_EXPR(DEFINE_CONSTRAINT, "define_constraint", "sse", RTX_EXTRA)
1037 DEF_RTL_EXPR(DEFINE_MEMORY_CONSTRAINT, "define_memory_constraint", "sse", RTX_EXTRA)
1038 DEF_RTL_EXPR(DEFINE_ADDRESS_CONSTRAINT, "define_address_constraint", "sse", RTX_EXTRA)
1039
1040
1041 /* Constructions for CPU pipeline description described by NDFAs.  */
1042
1043 /* (define_cpu_unit string [string]) describes cpu functional
1044    units (separated by comma).
1045
1046    1st operand: Names of cpu functional units.
1047    2nd operand: Name of automaton (see comments for DEFINE_AUTOMATON).
1048
1049    All define_reservations, define_cpu_units, and
1050    define_query_cpu_units should have unique names which may not be
1051    "nothing".  */
1052 DEF_RTL_EXPR(DEFINE_CPU_UNIT, "define_cpu_unit", "sS", RTX_EXTRA)
1053
1054 /* (define_query_cpu_unit string [string]) describes cpu functional
1055    units analogously to define_cpu_unit.  The reservation of such
1056    units can be queried for automaton state.  */
1057 DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT, "define_query_cpu_unit", "sS", RTX_EXTRA)
1058
1059 /* (exclusion_set string string) means that each CPU functional unit
1060    in the first string can not be reserved simultaneously with any
1061    unit whose name is in the second string and vise versa.  CPU units
1062    in the string are separated by commas.  For example, it is useful
1063    for description CPU with fully pipelined floating point functional
1064    unit which can execute simultaneously only single floating point
1065    insns or only double floating point insns.  All CPU functional
1066    units in a set should belong to the same automaton.  */
1067 DEF_RTL_EXPR(EXCLUSION_SET, "exclusion_set", "ss", RTX_EXTRA)
1068
1069 /* (presence_set string string) means that each CPU functional unit in
1070    the first string can not be reserved unless at least one of pattern
1071    of units whose names are in the second string is reserved.  This is
1072    an asymmetric relation.  CPU units or unit patterns in the strings
1073    are separated by commas.  Pattern is one unit name or unit names
1074    separated by white-spaces.
1075
1076    For example, it is useful for description that slot1 is reserved
1077    after slot0 reservation for a VLIW processor.  We could describe it
1078    by the following construction
1079
1080       (presence_set "slot1" "slot0")
1081
1082    Or slot1 is reserved only after slot0 and unit b0 reservation.  In
1083    this case we could write
1084
1085       (presence_set "slot1" "slot0 b0")
1086
1087    All CPU functional units in a set should belong to the same
1088    automaton.  */
1089 DEF_RTL_EXPR(PRESENCE_SET, "presence_set", "ss", RTX_EXTRA)
1090
1091 /* (final_presence_set string string) is analogous to `presence_set'.
1092    The difference between them is when checking is done.  When an
1093    instruction is issued in given automaton state reflecting all
1094    current and planned unit reservations, the automaton state is
1095    changed.  The first state is a source state, the second one is a
1096    result state.  Checking for `presence_set' is done on the source
1097    state reservation, checking for `final_presence_set' is done on the
1098    result reservation.  This construction is useful to describe a
1099    reservation which is actually two subsequent reservations.  For
1100    example, if we use
1101
1102       (presence_set "slot1" "slot0")
1103
1104    the following insn will be never issued (because slot1 requires
1105    slot0 which is absent in the source state).
1106
1107       (define_reservation "insn_and_nop" "slot0 + slot1")
1108
1109    but it can be issued if we use analogous `final_presence_set'.  */
1110 DEF_RTL_EXPR(FINAL_PRESENCE_SET, "final_presence_set", "ss", RTX_EXTRA)
1111
1112 /* (absence_set string string) means that each CPU functional unit in
1113    the first string can be reserved only if each pattern of units
1114    whose names are in the second string is not reserved.  This is an
1115    asymmetric relation (actually exclusion set is analogous to this
1116    one but it is symmetric).  CPU units or unit patterns in the string
1117    are separated by commas.  Pattern is one unit name or unit names
1118    separated by white-spaces.
1119
1120    For example, it is useful for description that slot0 can not be
1121    reserved after slot1 or slot2 reservation for a VLIW processor.  We
1122    could describe it by the following construction
1123
1124       (absence_set "slot2" "slot0, slot1")
1125
1126    Or slot2 can not be reserved if slot0 and unit b0 are reserved or
1127    slot1 and unit b1 are reserved .  In this case we could write
1128
1129       (absence_set "slot2" "slot0 b0, slot1 b1")
1130
1131    All CPU functional units in a set should to belong the same
1132    automaton.  */
1133 DEF_RTL_EXPR(ABSENCE_SET, "absence_set", "ss", RTX_EXTRA)
1134
1135 /* (final_absence_set string string) is analogous to `absence_set' but
1136    checking is done on the result (state) reservation.  See comments
1137    for `final_presence_set'.  */
1138 DEF_RTL_EXPR(FINAL_ABSENCE_SET, "final_absence_set", "ss", RTX_EXTRA)
1139
1140 /* (define_bypass number out_insn_names in_insn_names) names bypass
1141    with given latency (the first number) from insns given by the first
1142    string (see define_insn_reservation) into insns given by the second
1143    string.  Insn names in the strings are separated by commas.  The
1144    third operand is optional name of function which is additional
1145    guard for the bypass.  The function will get the two insns as
1146    parameters.  If the function returns zero the bypass will be
1147    ignored for this case.  Additional guard is necessary to recognize
1148    complicated bypasses, e.g. when consumer is load address.  If there
1149    are more one bypass with the same output and input insns, the
1150    chosen bypass is the first bypass with a guard in description whose
1151    guard function returns nonzero.  If there is no such bypass, then
1152    bypass without the guard function is chosen.  */
1153 DEF_RTL_EXPR(DEFINE_BYPASS, "define_bypass", "issS", RTX_EXTRA)
1154
1155 /* (define_automaton string) describes names of automata generated and
1156    used for pipeline hazards recognition.  The names are separated by
1157    comma.  Actually it is possibly to generate the single automaton
1158    but unfortunately it can be very large.  If we use more one
1159    automata, the summary size of the automata usually is less than the
1160    single one.  The automaton name is used in define_cpu_unit and
1161    define_query_cpu_unit.  All automata should have unique names.  */
1162 DEF_RTL_EXPR(DEFINE_AUTOMATON, "define_automaton", "s", RTX_EXTRA)
1163
1164 /* (automata_option string) describes option for generation of
1165    automata.  Currently there are the following options:
1166
1167    o "no-minimization" which makes no minimization of automata.  This
1168      is only worth to do when we are debugging the description and
1169      need to look more accurately at reservations of states.
1170
1171    o "time" which means printing additional time statistics about
1172       generation of automata.
1173
1174    o "v" which means generation of file describing the result
1175      automata.  The file has suffix `.dfa' and can be used for the
1176      description verification and debugging.
1177
1178    o "w" which means generation of warning instead of error for
1179      non-critical errors.
1180
1181    o "ndfa" which makes nondeterministic finite state automata.
1182
1183    o "progress" which means output of a progress bar showing how many
1184      states were generated so far for automaton being processed.  */
1185 DEF_RTL_EXPR(AUTOMATA_OPTION, "automata_option", "s", RTX_EXTRA)
1186
1187 /* (define_reservation string string) names reservation (the first
1188    string) of cpu functional units (the 2nd string).  Sometimes unit
1189    reservations for different insns contain common parts.  In such
1190    case, you can describe common part and use its name (the 1st
1191    parameter) in regular expression in define_insn_reservation.  All
1192    define_reservations, define_cpu_units, and define_query_cpu_units
1193    should have unique names which may not be "nothing".  */
1194 DEF_RTL_EXPR(DEFINE_RESERVATION, "define_reservation", "ss", RTX_EXTRA)
1195
1196 /* (define_insn_reservation name default_latency condition regexpr)
1197    describes reservation of cpu functional units (the 3nd operand) for
1198    instruction which is selected by the condition (the 2nd parameter).
1199    The first parameter is used for output of debugging information.
1200    The reservations are described by a regular expression according
1201    the following syntax:
1202
1203        regexp = regexp "," oneof
1204               | oneof
1205
1206        oneof = oneof "|" allof
1207              | allof
1208
1209        allof = allof "+" repeat
1210              | repeat
1211
1212        repeat = element "*" number
1213               | element
1214
1215        element = cpu_function_unit_name
1216                | reservation_name
1217                | result_name
1218                | "nothing"
1219                | "(" regexp ")"
1220
1221        1. "," is used for describing start of the next cycle in
1222        reservation.
1223
1224        2. "|" is used for describing the reservation described by the
1225        first regular expression *or* the reservation described by the
1226        second regular expression *or* etc.
1227
1228        3. "+" is used for describing the reservation described by the
1229        first regular expression *and* the reservation described by the
1230        second regular expression *and* etc.
1231
1232        4. "*" is used for convenience and simply means sequence in
1233        which the regular expression are repeated NUMBER times with
1234        cycle advancing (see ",").
1235
1236        5. cpu functional unit name which means its reservation.
1237
1238        6. reservation name -- see define_reservation.
1239
1240        7. string "nothing" means no units reservation.  */
1241
1242 DEF_RTL_EXPR(DEFINE_INSN_RESERVATION, "define_insn_reservation", "sies", RTX_EXTRA)
1243
1244 /* Expressions used for insn attributes.  */
1245
1246 /* Definition of an insn attribute.
1247    1st operand: name of the attribute
1248    2nd operand: comma-separated list of possible attribute values
1249    3rd operand: expression for the default value of the attribute.  */
1250 DEF_RTL_EXPR(DEFINE_ATTR, "define_attr", "sse", RTX_EXTRA)
1251
1252 /* Definition of an insn attribute that uses an existing enumerated type.
1253    1st operand: name of the attribute
1254    2nd operand: the name of the enumerated type
1255    3rd operand: expression for the default value of the attribute.  */
1256 DEF_RTL_EXPR(DEFINE_ENUM_ATTR, "define_enum_attr", "sse", RTX_EXTRA)
1257
1258 /* Marker for the name of an attribute.  */
1259 DEF_RTL_EXPR(ATTR, "attr", "s", RTX_EXTRA)
1260
1261 /* For use in the last (optional) operand of DEFINE_INSN or DEFINE_PEEPHOLE and
1262    in DEFINE_ASM_INSN to specify an attribute to assign to insns matching that
1263    pattern.
1264
1265    (set_attr "name" "value") is equivalent to
1266    (set (attr "name") (const_string "value"))  */
1267 DEF_RTL_EXPR(SET_ATTR, "set_attr", "ss", RTX_EXTRA)
1268
1269 /* In the last operand of DEFINE_INSN and DEFINE_PEEPHOLE, this can be used to
1270    specify that attribute values are to be assigned according to the
1271    alternative matched.
1272
1273    The following three expressions are equivalent:
1274
1275    (set (attr "att") (cond [(eq_attrq "alternative" "1") (const_string "a1")
1276                             (eq_attrq "alternative" "2") (const_string "a2")]
1277                            (const_string "a3")))
1278    (set_attr_alternative "att" [(const_string "a1") (const_string "a2")
1279                                  (const_string "a3")])
1280    (set_attr "att" "a1,a2,a3")
1281  */
1282 DEF_RTL_EXPR(SET_ATTR_ALTERNATIVE, "set_attr_alternative", "sE", RTX_EXTRA)
1283
1284 /* A conditional expression true if the value of the specified attribute of
1285    the current insn equals the specified value.  The first operand is the
1286    attribute name and the second is the comparison value.  */
1287 DEF_RTL_EXPR(EQ_ATTR, "eq_attr", "ss", RTX_EXTRA)
1288
1289 /* A special case of the above representing a set of alternatives.  The first
1290    operand is bitmap of the set, the second one is the default value.  */
1291 DEF_RTL_EXPR(EQ_ATTR_ALT, "eq_attr_alt", "ii", RTX_EXTRA)
1292
1293 /* A conditional expression which is true if the specified flag is
1294    true for the insn being scheduled in reorg.
1295
1296    genattr.c defines the following flags which can be tested by
1297    (attr_flag "foo") expressions in eligible_for_delay: forward, backward.  */
1298
1299 DEF_RTL_EXPR (ATTR_FLAG, "attr_flag", "s", RTX_EXTRA)
1300
1301 /* General conditional. The first operand is a vector composed of pairs of
1302    expressions.  The first element of each pair is evaluated, in turn.
1303    The value of the conditional is the second expression of the first pair
1304    whose first expression evaluates nonzero.  If none of the expressions is
1305    true, the second operand will be used as the value of the conditional.  */
1306 DEF_RTL_EXPR(COND, "cond", "Ee", RTX_EXTRA)
1307
1308 /* Definition of a pattern substitution meta operation on a DEFINE_EXPAND
1309    or a DEFINE_INSN.  Automatically generates new instances of DEFINE_INSNs
1310    that match the substitution pattern.
1311
1312    Operand:
1313    0: The name of the substitition template.
1314    1: Input template to match to see if a substitution is applicable.
1315    2: A C expression giving an additional condition for the generated
1316       new define_expand or define_insn.
1317    3: Output tempalate to generate via substitution.
1318
1319    Within a DEFINE_SUBST template, the meaning of some RTL expressions is
1320    different from their usual interpretation: a MATCH_OPERAND matches any
1321    expression tree with matching machine mode or with VOIDmode.  Likewise,
1322    MATCH_OP_DUP and MATCH_DUP match more liberally in a DEFINE_SUBST than
1323    in other RTL expressions.  MATCH_OPERATOR matches all common operators
1324    but also UNSPEC, UNSPEC_VOLATILE, and MATCH_OPERATORS from the input
1325    DEFINE_EXPAND or DEFINE_INSN.  */
1326 DEF_RTL_EXPR(DEFINE_SUBST, "define_subst", "sEsE", RTX_EXTRA)
1327
1328 /* Substitution attribute to apply a DEFINE_SUBST to a pattern.
1329
1330    Operand:
1331    0: The name of the subst-attribute.
1332    1: The name of the DEFINE_SUBST to be applied for this attribute.
1333    2: String to substitute for the subst-attribute name in the pattern
1334       name, for the case that the DEFINE_SUBST is not applied (i.e. the
1335       unmodified version of the pattern).
1336    3: String to substitute for the subst-attribute name in the pattern
1337       name, for the case that the DEFINE_SUBST is applied to the patten.
1338
1339    The use of DEFINE_SUBST and DEFINE_SUBST_ATTR is explained in the
1340    GCC internals manual, under "RTL Templates Transformations".  */
1341 DEF_RTL_EXPR(DEFINE_SUBST_ATTR, "define_subst_attr", "ssss", RTX_EXTRA)
1342
1343 #endif /* GENERATOR_FILE */
1344
1345 /*
1346 Local variables:
1347 mode:c
1348 End:
1349 */