gcc/expr.h

   1 /* Definitions for code generation pass of GNU compiler.
   2    Copyright (C) 1987, 1991, 1992, 1993, 1994 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU CC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20
  21 #ifndef __STDC__
  22 #ifndef const
  23 #define const
  24 #endif
  25 #endif
  26
  27 /* The default branch cost is 1.  */
  28 #ifndef BRANCH_COST
  29 #define BRANCH_COST 1
  30 #endif
  31
  32 /* Macros to access the slots of a QUEUED rtx.
  33    Here rather than in rtl.h because only the expansion pass
  34    should ever encounter a QUEUED.  */
  35
  36 /* The variable for which an increment is queued.  */
  37 #define QUEUED_VAR(P) XEXP (P, 0)
  38 /* If the increment has been emitted, this is the insn
  39    that does the increment.  It is zero before the increment is emitted.  */
  40 #define QUEUED_INSN(P) XEXP (P, 1)
  41 /* If a pre-increment copy has been generated, this is the copy
  42    (it is a temporary reg).  Zero if no copy made yet.  */
  43 #define QUEUED_COPY(P) XEXP (P, 2)
  44 /* This is the body to use for the insn to do the increment.
  45    It is used to emit the increment.  */
  46 #define QUEUED_BODY(P) XEXP (P, 3)
  47 /* Next QUEUED in the queue.  */
  48 #define QUEUED_NEXT(P) XEXP (P, 4)
  49
  50 /* This is the 4th arg to `expand_expr'.
  51    EXPAND_SUM means it is ok to return a PLUS rtx or MULT rtx.
  52    EXPAND_INITIALIZER is similar but also record any labels on forced_labels.
  53    EXPAND_CONST_ADDRESS means it is ok to return a MEM whose address
  54     is a constant that is not a legitimate address.  */
  55 enum expand_modifier {EXPAND_NORMAL, EXPAND_SUM,
  56                       EXPAND_CONST_ADDRESS, EXPAND_INITIALIZER};
  57
  58 /* List of labels that must never be deleted.  */
  59 extern rtx forced_labels;
  60
  61 /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
  62    So we can mark them all live at the end of the function, if stupid.  */
  63 extern rtx save_expr_regs;
  64
  65 extern int current_function_calls_alloca;
  66 extern int current_function_outgoing_args_size;
  67
  68 /* This is the offset from the arg pointer to the place where the first
  69    anonymous arg can be found, if there is one.  */
  70 extern rtx current_function_arg_offset_rtx;
  71
  72 /* This is nonzero if the current function uses the constant pool.  */
  73 extern int current_function_uses_const_pool;
  74
  75 /* This is nonzero if the current function uses pic_offset_table_rtx.  */
  76 extern int current_function_uses_pic_offset_table;
  77
  78 /* The arg pointer hard register, or the pseudo into which it was copied.  */
  79 extern rtx current_function_internal_arg_pointer;
  80
  81 /* Nonzero means stack pops must not be deferred, and deferred stack
  82    pops must not be output.  It is nonzero inside a function call,
  83    inside a conditional expression, inside a statement expression,
  84    and in other cases as well.  */
  85 extern int inhibit_defer_pop;
  86
  87 /* Number of function calls seen so far in current function.  */
  88
  89 extern int function_call_count;
  90
  91 /* RTX for stack slot that holds the current handler for nonlocal gotos.
  92    Zero when function does not have nonlocal labels.  */
  93
  94 extern rtx nonlocal_goto_handler_slot;
  95
  96 /* RTX for stack slot that holds the stack pointer value to restore
  97    for a nonlocal goto.
  98    Zero when function does not have nonlocal labels.  */
  99
 100 extern rtx nonlocal_goto_stack_level;
 101
 102 /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
 103    (labels to which there can be nonlocal gotos from nested functions)
 104    in this function.  */
 105
 106 #ifdef TREE_CODE   /* Don't lose if tree.h not included.  */
 107 extern tree nonlocal_labels;
 108 #endif
 109
 110 #define NO_DEFER_POP (inhibit_defer_pop += 1)
 111 #define OK_DEFER_POP (inhibit_defer_pop -= 1)
 112
 113 /* Number of units that we should eventually pop off the stack.
 114    These are the arguments to function calls that have already returned.  */
 115 extern int pending_stack_adjust;
 116
 117 /* A list of all cleanups which belong to the arguments of
 118    function calls being expanded by expand_call.  */
 119 #ifdef TREE_CODE   /* Don't lose if tree.h not included.  */
 120 extern tree cleanups_this_call;
 121 #endif
 122
 123 /* When temporaries are created by TARGET_EXPRs, they are created at
 124    this level of temp_slot_level, so that they can remain allocated
 125    until no longer needed.  CLEANUP_POINT_EXPRs define the lifetime
 126    of TARGET_EXPRs.  */
 127 extern int target_temp_slot_level;
 128 \f
 129 #ifdef TREE_CODE /* Don't lose if tree.h not included.  */
 130 /* Structure to record the size of a sequence of arguments
 131    as the sum of a tree-expression and a constant.  */
 132
 133 struct args_size
 134 {
 135   int constant;
 136   tree var;
 137 };
 138 #endif
 139
 140 /* Add the value of the tree INC to the `struct args_size' TO.  */
 141
 142 #define ADD_PARM_SIZE(TO, INC)  \
 143 { tree inc = (INC);                             \
 144   if (TREE_CODE (inc) == INTEGER_CST)           \
 145     (TO).constant += TREE_INT_CST_LOW (inc);    \
 146   else if ((TO).var == 0)                       \
 147     (TO).var = inc;                             \
 148   else                                          \
 149     (TO).var = size_binop (PLUS_EXPR, (TO).var, inc); }
 150
 151 #define SUB_PARM_SIZE(TO, DEC)  \
 152 { tree dec = (DEC);                             \
 153   if (TREE_CODE (dec) == INTEGER_CST)           \
 154     (TO).constant -= TREE_INT_CST_LOW (dec);    \
 155   else if ((TO).var == 0)                       \
 156     (TO).var = size_binop (MINUS_EXPR, integer_zero_node, dec); \
 157   else                                          \
 158     (TO).var = size_binop (MINUS_EXPR, (TO).var, dec); }
 159
 160 /* Convert the implicit sum in a `struct args_size' into an rtx.  */
 161 #define ARGS_SIZE_RTX(SIZE)                                             \
 162 ((SIZE).var == 0 ? GEN_INT ((SIZE).constant)    \
 163  : expand_expr (size_binop (PLUS_EXPR, (SIZE).var,                      \
 164                             size_int ((SIZE).constant)),                \
 165                 NULL_RTX, VOIDmode, 0))
 166
 167 /* Convert the implicit sum in a `struct args_size' into a tree.  */
 168 #define ARGS_SIZE_TREE(SIZE)                                            \
 169 ((SIZE).var == 0 ? size_int ((SIZE).constant)                           \
 170  : size_binop (PLUS_EXPR, (SIZE).var, size_int ((SIZE).constant)))
 171
 172 /* Supply a default definition for FUNCTION_ARG_PADDING:
 173    usually pad upward, but pad short args downward on
 174    big-endian machines.  */
 175
 176 enum direction {none, upward, downward};  /* Value has this type.  */
 177
 178 #ifndef FUNCTION_ARG_PADDING
 179 #if BYTES_BIG_ENDIAN
 180 #define FUNCTION_ARG_PADDING(MODE, TYPE)                                \
 181   (((MODE) == BLKmode                                                   \
 182     ? ((TYPE) && TREE_CODE (TYPE_SIZE (TYPE)) == INTEGER_CST            \
 183        && int_size_in_bytes (TYPE) < (PARM_BOUNDARY / BITS_PER_UNIT))   \
 184     : GET_MODE_BITSIZE (MODE) < PARM_BOUNDARY)                          \
 185    ? downward : upward)
 186 #else
 187 #define FUNCTION_ARG_PADDING(MODE, TYPE) upward
 188 #endif
 189 #endif
 190
 191 /* Supply a default definition for FUNCTION_ARG_BOUNDARY.  Normally, we let
 192    FUNCTION_ARG_PADDING, which also pads the length, handle any needed
 193    alignment.  */
 194
 195 #ifndef FUNCTION_ARG_BOUNDARY
 196 #define FUNCTION_ARG_BOUNDARY(MODE, TYPE)       PARM_BOUNDARY
 197 #endif
 198
 199 /* Nonzero if we do not know how to pass TYPE solely in registers.
 200    We cannot do so in the following cases:
 201
 202    - if the type has variable size
 203    - if the type is marked as addressable (it is required to be constructed
 204      into the stack)
 205    - if the padding and mode of the type is such that a copy into a register
 206      would put it into the wrong part of the register.
 207
 208    Which padding can't be supported depends on the byte endianness.
 209
 210    A value in a register is implicitly padded at the most significant end.
 211    On a big-endian machine, that is the lower end in memory.
 212    So a value padded in memory at the upper end can't go in a register.
 213    For a little-endian machine, the reverse is true.  */
 214
 215 #if BYTES_BIG_ENDIAN
 216 #define MUST_PASS_IN_STACK_BAD_PADDING  upward
 217 #else
 218 #define MUST_PASS_IN_STACK_BAD_PADDING  downward
 219 #endif
 220
 221 #define MUST_PASS_IN_STACK(MODE,TYPE)                   \
 222   ((TYPE) != 0                                          \
 223    && (TREE_CODE (TYPE_SIZE (TYPE)) != INTEGER_CST      \
 224        || TREE_ADDRESSABLE (TYPE)                       \
 225        || ((MODE) == BLKmode                            \
 226            && ! ((TYPE) != 0 && TREE_CODE (TYPE_SIZE (TYPE)) == INTEGER_CST \
 227                  && 0 == (int_size_in_bytes (TYPE)      \
 228                           % (PARM_BOUNDARY / BITS_PER_UNIT))) \
 229            && (FUNCTION_ARG_PADDING (MODE, TYPE)        \
 230                == MUST_PASS_IN_STACK_BAD_PADDING))))
 231
 232 /* Nonzero if type TYPE should be returned in memory.
 233    Most machines can use the following default definition.  */
 234
 235 #ifndef RETURN_IN_MEMORY
 236 #define RETURN_IN_MEMORY(TYPE) (TYPE_MODE (TYPE) == BLKmode)
 237 #endif
 238 \f
 239 /* Optabs are tables saying how to generate insn bodies
 240    for various machine modes and numbers of operands.
 241    Each optab applies to one operation.
 242    For example, add_optab applies to addition.
 243
 244    The insn_code slot is the enum insn_code that says how to
 245    generate an insn for this operation on a particular machine mode.
 246    It is CODE_FOR_nothing if there is no such insn on the target machine.
 247
 248    The `lib_call' slot is the name of the library function that
 249    can be used to perform the operation.
 250
 251    A few optabs, such as move_optab and cmp_optab, are used
 252    by special code.  */
 253
 254 /* Everything that uses expr.h needs to define enum insn_code
 255    but we don't list it in the Makefile dependencies just for that.  */
 256 #include "insn-codes.h"
 257
 258 typedef struct optab
 259 {
 260   enum rtx_code code;
 261   struct {
 262     enum insn_code insn_code;
 263     rtx libfunc;
 264   } handlers [NUM_MACHINE_MODES];
 265 } * optab;
 266
 267 /* Given an enum insn_code, access the function to construct
 268    the body of that kind of insn.  */
 269 #ifdef FUNCTION_CONVERSION_BUG
 270 /* Some compilers fail to convert a function properly to a
 271    pointer-to-function when used as an argument.
 272    So produce the pointer-to-function directly.
 273    Luckily, these compilers seem to work properly when you
 274    call the pointer-to-function.  */
 275 #define GEN_FCN(CODE) (insn_gen_function[(int) (CODE)])
 276 #else
 277 #define GEN_FCN(CODE) (*insn_gen_function[(int) (CODE)])
 278 #endif
 279
 280 extern rtx (*const insn_gen_function[]) ();
 281
 282 extern optab add_optab;
 283 extern optab sub_optab;
 284 extern optab smul_optab;        /* Signed and floating-point multiply */
 285 extern optab smul_highpart_optab; /* Signed multiply, return high word */
 286 extern optab umul_highpart_optab;
 287 extern optab smul_widen_optab;  /* Signed multiply with result
 288                                    one machine mode wider than args */
 289 extern optab umul_widen_optab;
 290 extern optab sdiv_optab;        /* Signed divide */
 291 extern optab sdivmod_optab;     /* Signed divide-and-remainder in one */
 292 extern optab udiv_optab;
 293 extern optab udivmod_optab;
 294 extern optab smod_optab;        /* Signed remainder */
 295 extern optab umod_optab;
 296 extern optab flodiv_optab;      /* Optab for floating divide. */
 297 extern optab ftrunc_optab;      /* Convert float to integer in float fmt */
 298 extern optab and_optab;         /* Logical and */
 299 extern optab ior_optab;         /* Logical or */
 300 extern optab xor_optab;         /* Logical xor */
 301 extern optab ashl_optab;        /* Arithmetic shift left */
 302 extern optab ashr_optab;        /* Arithmetic shift right */
 303 extern optab lshr_optab;        /* Logical shift right */
 304 extern optab rotl_optab;        /* Rotate left */
 305 extern optab rotr_optab;        /* Rotate right */
 306 extern optab smin_optab;        /* Signed and floating-point minimum value */
 307 extern optab smax_optab;        /* Signed and floating-point maximum value */
 308 extern optab umin_optab;        /* Unsigned minimum value */
 309 extern optab umax_optab;        /* Unsigned maximum value */
 310
 311 extern optab mov_optab;         /* Move instruction.  */
 312 extern optab movstrict_optab;   /* Move, preserving high part of register.  */
 313
 314 extern optab cmp_optab;         /* Compare insn; two operands.  */
 315 extern optab tst_optab;         /* tst insn; compare one operand against 0 */
 316
 317 /* Unary operations */
 318 extern optab neg_optab;         /* Negation */
 319 extern optab abs_optab;         /* Abs value */
 320 extern optab one_cmpl_optab;    /* Bitwise not */
 321 extern optab ffs_optab;         /* Find first bit set */
 322 extern optab sqrt_optab;        /* Square root */
 323 extern optab sin_optab;         /* Sine */
 324 extern optab cos_optab;         /* Cosine */
 325 extern optab strlen_optab;      /* String length */
 326
 327 /* Tables of patterns for extending one integer mode to another.  */
 328 extern enum insn_code extendtab[MAX_MACHINE_MODE][MAX_MACHINE_MODE][2];
 329
 330 /* Tables of patterns for converting between fixed and floating point. */
 331 extern enum insn_code fixtab[NUM_MACHINE_MODES][NUM_MACHINE_MODES][2];
 332 extern enum insn_code fixtrunctab[NUM_MACHINE_MODES][NUM_MACHINE_MODES][2];
 333 extern enum insn_code floattab[NUM_MACHINE_MODES][NUM_MACHINE_MODES][2];
 334
 335 /* Contains the optab used for each rtx code.  */
 336 extern optab code_to_optab[NUM_RTX_CODE + 1];
 337
 338 /* Passed to expand_binop and expand_unop to say which options to try to use
 339    if the requested operation can't be open-coded on the requisite mode.
 340    Either OPTAB_LIB or OPTAB_LIB_WIDEN says try using a library call.
 341    Either OPTAB_WIDEN or OPTAB_LIB_WIDEN says try using a wider mode.
 342    OPTAB_MUST_WIDEN says try widening and don't try anything else.  */
 343
 344 enum optab_methods
 345 {
 346   OPTAB_DIRECT,
 347   OPTAB_LIB,
 348   OPTAB_WIDEN,
 349   OPTAB_LIB_WIDEN,
 350   OPTAB_MUST_WIDEN
 351 };
 352
 353 /* SYMBOL_REF rtx's for the library functions that are called
 354    implicitly and not via optabs.  */
 355
 356 extern rtx extendsfdf2_libfunc;
 357 extern rtx extendsfxf2_libfunc;
 358 extern rtx extendsftf2_libfunc;
 359 extern rtx extenddfxf2_libfunc;
 360 extern rtx extenddftf2_libfunc;
 361
 362 extern rtx truncdfsf2_libfunc;
 363 extern rtx truncxfsf2_libfunc;
 364 extern rtx trunctfsf2_libfunc;
 365 extern rtx truncxfdf2_libfunc;
 366 extern rtx trunctfdf2_libfunc;
 367
 368 extern rtx memcpy_libfunc;
 369 extern rtx bcopy_libfunc;
 370 extern rtx memcmp_libfunc;
 371 extern rtx bcmp_libfunc;
 372 extern rtx memset_libfunc;
 373 extern rtx bzero_libfunc;
 374
 375 extern rtx eqsf2_libfunc;
 376 extern rtx nesf2_libfunc;
 377 extern rtx gtsf2_libfunc;
 378 extern rtx gesf2_libfunc;
 379 extern rtx ltsf2_libfunc;
 380 extern rtx lesf2_libfunc;
 381
 382 extern rtx eqdf2_libfunc;
 383 extern rtx nedf2_libfunc;
 384 extern rtx gtdf2_libfunc;
 385 extern rtx gedf2_libfunc;
 386 extern rtx ltdf2_libfunc;
 387 extern rtx ledf2_libfunc;
 388
 389 extern rtx eqxf2_libfunc;
 390 extern rtx nexf2_libfunc;
 391 extern rtx gtxf2_libfunc;
 392 extern rtx gexf2_libfunc;
 393 extern rtx ltxf2_libfunc;
 394 extern rtx lexf2_libfunc;
 395
 396 extern rtx eqtf2_libfunc;
 397 extern rtx netf2_libfunc;
 398 extern rtx gttf2_libfunc;
 399 extern rtx getf2_libfunc;
 400 extern rtx lttf2_libfunc;
 401 extern rtx letf2_libfunc;
 402
 403 extern rtx floatsisf_libfunc;
 404 extern rtx floatdisf_libfunc;
 405 extern rtx floattisf_libfunc;
 406
 407 extern rtx floatsidf_libfunc;
 408 extern rtx floatdidf_libfunc;
 409 extern rtx floattidf_libfunc;
 410
 411 extern rtx floatsixf_libfunc;
 412 extern rtx floatdixf_libfunc;
 413 extern rtx floattixf_libfunc;
 414
 415 extern rtx floatsitf_libfunc;
 416 extern rtx floatditf_libfunc;
 417 extern rtx floattitf_libfunc;
 418
 419 extern rtx fixsfsi_libfunc;
 420 extern rtx fixsfdi_libfunc;
 421 extern rtx fixsfti_libfunc;
 422
 423 extern rtx fixdfsi_libfunc;
 424 extern rtx fixdfdi_libfunc;
 425 extern rtx fixdfti_libfunc;
 426
 427 extern rtx fixxfsi_libfunc;
 428 extern rtx fixxfdi_libfunc;
 429 extern rtx fixxfti_libfunc;
 430
 431 extern rtx fixtfsi_libfunc;
 432 extern rtx fixtfdi_libfunc;
 433 extern rtx fixtfti_libfunc;
 434
 435 extern rtx fixunssfsi_libfunc;
 436 extern rtx fixunssfdi_libfunc;
 437 extern rtx fixunssfti_libfunc;
 438
 439 extern rtx fixunsdfsi_libfunc;
 440 extern rtx fixunsdfdi_libfunc;
 441 extern rtx fixunsdfti_libfunc;
 442
 443 extern rtx fixunsxfsi_libfunc;
 444 extern rtx fixunsxfdi_libfunc;
 445 extern rtx fixunsxfti_libfunc;
 446
 447 extern rtx fixunstfsi_libfunc;
 448 extern rtx fixunstfdi_libfunc;
 449 extern rtx fixunstfti_libfunc;
 450 \f
 451 typedef rtx (*rtxfun) ();
 452
 453 /* Indexed by the rtx-code for a conditional (eg. EQ, LT,...)
 454    gives the gen_function to make a branch to test that condition.  */
 455
 456 extern rtxfun bcc_gen_fctn[NUM_RTX_CODE];
 457
 458 /* Indexed by the rtx-code for a conditional (eg. EQ, LT,...)
 459    gives the insn code to make a store-condition insn
 460    to test that condition.  */
 461
 462 extern enum insn_code setcc_gen_code[NUM_RTX_CODE];
 463
 464 /* This array records the insn_code of insns to perform block moves.  */
 465 extern enum insn_code movstr_optab[NUM_MACHINE_MODES];
 466
 467 /* Define functions given in optabs.c.  */
 468
 469 /* Expand a binary operation given optab and rtx operands.  */
 470 extern rtx expand_binop PROTO((enum machine_mode, optab, rtx, rtx, rtx,
 471                                int, enum optab_methods));
 472
 473 /* Expand a binary operation with both signed and unsigned forms.  */
 474 extern rtx sign_expand_binop PROTO((enum machine_mode, optab, optab, rtx,
 475                                     rtx, rtx, int, enum optab_methods));
 476
 477 /* Generate code to perform an operation on two operands with two results.  */
 478 extern int expand_twoval_binop PROTO((optab, rtx, rtx, rtx, rtx, int));
 479
 480 /* Expand a unary arithmetic operation given optab rtx operand.  */
 481 extern rtx expand_unop PROTO((enum machine_mode, optab, rtx, rtx, int));
 482
 483 /* Expand the complex absolute value operation.  */
 484 extern rtx expand_complex_abs PROTO((enum machine_mode, rtx, rtx, int));
 485
 486 /* Generate an instruction with a given INSN_CODE with an output and
 487    an input.  */
 488 extern void emit_unop_insn PROTO((int, rtx, rtx, enum rtx_code));
 489
 490 /* Emit code to perform a series of operations on a multi-word quantity, one
 491    word at a time.  */
 492 extern rtx emit_no_conflict_block PROTO((rtx, rtx, rtx, rtx, rtx));
 493
 494 /* Emit code to make a call to a constant function or a library call. */
 495 extern void emit_libcall_block PROTO((rtx, rtx, rtx, rtx));
 496
 497 /* Emit one rtl instruction to store zero in specified rtx.  */
 498 extern void emit_clr_insn PROTO((rtx));
 499
 500 /* Emit one rtl insn to store 1 in specified rtx assuming it contains 0.  */
 501 extern void emit_0_to_1_insn PROTO((rtx));
 502
 503 /* Emit one rtl insn to compare two rtx's.  */
 504 extern void emit_cmp_insn PROTO((rtx, rtx, enum rtx_code, rtx,
 505                                  enum machine_mode, int, int));
 506
 507 /* Nonzero if a compare of mode MODE can be done straightforwardly
 508    (without splitting it into pieces).  */
 509 extern int can_compare_p PROTO((enum machine_mode));
 510
 511 /* Emit a library call comparison between floating point X and Y.
 512    COMPARISON is the rtl operator to compare with (EQ, NE, GT, etc.).  */
 513 extern void emit_float_lib_cmp PROTO((rtx, rtx, enum rtx_code));
 514
 515 /* Generate code to indirectly jump to a location given in the rtx LOC.  */
 516 extern void emit_indirect_jump PROTO((rtx));
 517
 518 /* Create but don't emit one rtl instruction to add one rtx into another.
 519    Modes must match; operands must meet the operation's predicates.
 520    Likewise for subtraction and for just copying.
 521    These do not call protect_from_queue; caller must do so.  */
 522 extern rtx gen_add2_insn PROTO((rtx, rtx));
 523 extern rtx gen_sub2_insn PROTO((rtx, rtx));
 524 extern rtx gen_move_insn PROTO((rtx, rtx));
 525 extern int have_add2_insn PROTO((enum machine_mode));
 526 extern int have_sub2_insn PROTO((enum machine_mode));
 527
 528 /* Return the INSN_CODE to use for an extend operation.  */
 529 extern enum insn_code can_extend_p PROTO((enum machine_mode,
 530                                           enum machine_mode, int));
 531
 532 /* Generate the body of an insn to extend Y (with mode MFROM)
 533    into X (with mode MTO).  Do zero-extension if UNSIGNEDP is nonzero.  */
 534 extern rtx gen_extend_insn PROTO((rtx, rtx, enum machine_mode,
 535                                   enum machine_mode, int));
 536
 537 /* Initialize the tables that control conversion between fixed and
 538    floating values.  */
 539 extern void init_fixtab PROTO((void));
 540 extern void init_floattab PROTO((void));
 541
 542 /* Generate code for a FLOAT_EXPR.  */
 543 extern void expand_float PROTO((rtx, rtx, int));
 544
 545 /* Generate code for a FIX_EXPR.  */
 546 extern void expand_fix PROTO((rtx, rtx, int));
 547
 548 /* Call this once to initialize the contents of the optabs
 549    appropriately for the current target machine.  */
 550 extern void init_optabs PROTO((void));
 551 \f
 552 /* Functions from expmed.c:  */
 553
 554 /* Arguments MODE, RTX: return an rtx for the negation of that value.
 555    May emit insns.  */
 556 extern rtx negate_rtx PROTO((enum machine_mode, rtx));
 557
 558 /* Expand a logical AND operation.  */
 559 extern rtx expand_and PROTO((rtx, rtx, rtx));
 560
 561 /* Emit a store-flag operation.  */
 562 extern rtx emit_store_flag PROTO((rtx, enum rtx_code, rtx, rtx,
 563                                   enum machine_mode, int, int));
 564
 565 /* Functions from loop.c:  */
 566
 567 /* Given a JUMP_INSN, return a description of the test being made.  */
 568 extern rtx get_condition PROTO((rtx, rtx *));
 569 \f
 570 /* Functions from expr.c:  */
 571
 572 /* This is run once per compilation to set up which modes can be used
 573    directly in memory and to initialize the block move optab.  */
 574 extern void init_expr_once PROTO((void));
 575
 576 /* This is run at the start of compiling a function.  */
 577 extern void init_expr PROTO((void));
 578
 579 /* Use protect_from_queue to convert a QUEUED expression
 580    into something that you can put immediately into an instruction.  */
 581 extern rtx protect_from_queue PROTO((rtx, int));
 582
 583 /* Perform all the pending incrementations.  */
 584 extern void emit_queue PROTO((void));
 585
 586 /* Emit some rtl insns to move data between rtx's, converting machine modes.
 587    Both modes must be floating or both fixed.  */
 588 extern void convert_move PROTO((rtx, rtx, int));
 589
 590 /* Convert an rtx to specified machine mode and return the result.  */
 591 extern rtx convert_to_mode PROTO((enum machine_mode, rtx, int));
 592
 593 /* Convert an rtx to MODE from OLDMODE and return the result.  */
 594 extern rtx convert_modes PROTO((enum machine_mode, enum machine_mode, rtx, int));
 595
 596 /* Emit code to move a block Y to a block X.  */
 597 extern void emit_block_move PROTO((rtx, rtx, rtx, int));
 598
 599 /* Copy all or part of a value X into registers starting at REGNO.
 600    The number of registers to be filled is NREGS.  */
 601 extern void move_block_to_reg PROTO((int, rtx, int, enum machine_mode));
 602
 603 /* Copy all or part of a BLKmode value X out of registers starting at REGNO.
 604    The number of registers to be filled is NREGS.  */
 605 extern void move_block_from_reg PROTO((int, rtx, int, int));
 606
 607 /* Mark REG as holding a parameter for the next CALL_INSN.  */
 608 extern void use_reg PROTO((rtx*, rtx));
 609 /* Mark NREGS consecutive regs, starting at REGNO, as holding parameters
 610    for the next CALL_INSN.  */
 611 extern void use_regs PROTO((rtx*, int, int));
 612
 613 /* Write zeros through the storage of OBJECT.
 614    If OBJECT has BLKmode, SIZE is its length in bytes.  */
 615 extern void clear_storage PROTO((rtx, int));
 616
 617 /* Emit insns to set X from Y.  */
 618 extern rtx emit_move_insn PROTO((rtx, rtx));
 619
 620 /* Emit insns to set X from Y, with no frills.  */
 621 extern rtx emit_move_insn_1 PROTO ((rtx, rtx));
 622
 623 /* Push a block of length SIZE (perhaps variable)
 624    and return an rtx to address the beginning of the block.  */
 625 extern rtx push_block PROTO((rtx, int, int));
 626
 627 /* Make an operand to push someting on the stack.  */
 628 extern rtx gen_push_operand PROTO((void));
 629
 630 #ifdef TREE_CODE
 631 /* Generate code to push something onto the stack, given its mode and type.  */
 632 extern void emit_push_insn PROTO((rtx, enum machine_mode, tree, rtx, int,
 633                                   int, rtx, int, rtx, rtx));
 634
 635 /* Emit library call.  */
 636 extern void emit_library_call PVPROTO((rtx orgfun, int no_queue,
 637   enum machine_mode outmode, int nargs, ...));
 638 extern rtx emit_library_call_value PVPROTO((rtx orgfun, rtx value, int no_queue,
 639   enum machine_mode outmode, int nargs, ...));
 640
 641 /* Expand an assignment that stores the value of FROM into TO. */
 642 extern rtx expand_assignment PROTO((tree, tree, int, int));
 643
 644 /* Generate code for computing expression EXP,
 645    and storing the value into TARGET.
 646    If SUGGEST_REG is nonzero, copy the value through a register
 647    and return that register, if that is possible.  */
 648 extern rtx store_expr PROTO((tree, rtx, int));
 649 #endif
 650
 651 /* Given an rtx that may include add and multiply operations,
 652    generate them as insns and return a pseudo-reg containing the value.
 653    Useful after calling expand_expr with 1 as sum_ok.  */
 654 extern rtx force_operand PROTO((rtx, rtx));
 655
 656 #ifdef TREE_CODE
 657 /* Generate code for computing expression EXP.
 658    An rtx for the computed value is returned.  The value is never null.
 659    In the case of a void EXP, const0_rtx is returned.  */
 660 extern rtx expand_expr PROTO((tree, rtx, enum machine_mode,
 661                               enum expand_modifier));
 662 #endif
 663
 664 /* At the start of a function, record that we have no previously-pushed
 665    arguments waiting to be popped.  */
 666 extern void init_pending_stack_adjust PROTO((void));
 667
 668 /* When exiting from function, if safe, clear out any pending stack adjust
 669    so the adjustment won't get done.  */
 670 extern void clear_pending_stack_adjust PROTO((void));
 671
 672 /* Pop any previously-pushed arguments that have not been popped yet.  */
 673 extern void do_pending_stack_adjust PROTO((void));
 674
 675 #ifdef TREE_CODE
 676 /* Expand all cleanups up to OLD_CLEANUPS.  */
 677 extern void expand_cleanups_to PROTO((tree));
 678
 679 /* Generate code to evaluate EXP and jump to LABEL if the value is zero.  */
 680 extern void jumpifnot PROTO((tree, rtx));
 681
 682 /* Generate code to evaluate EXP and jump to LABEL if the value is nonzero.  */
 683 extern void jumpif PROTO((tree, rtx));
 684
 685 /* Generate code to evaluate EXP and jump to IF_FALSE_LABEL if
 686    the result is zero, or IF_TRUE_LABEL if the result is one.  */
 687 extern void do_jump PROTO((tree, rtx, rtx));
 688 #endif
 689
 690 /* Generate rtl to compare two rtx's, will call emit_cmp_insn.  */
 691 extern rtx compare_from_rtx PROTO((rtx, rtx, enum rtx_code, int,
 692                                    enum machine_mode, rtx, int));
 693
 694 /* Generate a tablejump instruction (used for switch statements).  */
 695 extern void do_tablejump PROTO((rtx, enum machine_mode, rtx, rtx, rtx));
 696 \f
 697 #ifdef TREE_CODE
 698 /* rtl.h and tree.h were included.  */
 699 /* Return an rtx for the size in bytes of the value of an expr.  */
 700 extern rtx expr_size PROTO((tree));
 701
 702 extern rtx lookup_static_chain PROTO((tree));
 703
 704 /* Convert a stack slot address ADDR valid in function FNDECL
 705    into an address valid in this function (using a static chain).  */
 706 extern rtx fix_lexical_addr PROTO((rtx, tree));
 707
 708 /* Return the address of the trampoline for entering nested fn FUNCTION.  */
 709 extern rtx trampoline_address PROTO((tree));
 710
 711 /* Return an rtx that refers to the value returned by a function
 712    in its original home.  This becomes invalid if any more code is emitted.  */
 713 extern rtx hard_function_value PROTO((tree, tree));
 714
 715 extern rtx prepare_call_address PROTO((rtx, tree, rtx *, int));
 716
 717 extern rtx expand_call PROTO((tree, rtx, int));
 718
 719 extern rtx expand_shift PROTO((enum tree_code, enum machine_mode, rtx, tree, rtx, int));
 720 extern rtx expand_divmod PROTO((int, enum tree_code, enum machine_mode, rtx, rtx, rtx, int));
 721 extern void locate_and_pad_parm PROTO((enum machine_mode, tree, int, tree, struct args_size *, struct args_size *, struct args_size *));
 722 extern rtx expand_inline_function PROTO((tree, tree, rtx, int, tree, rtx));
 723 /* Return the CODE_LABEL rtx for a LABEL_DECL, creating it if necessary.  */
 724 extern rtx label_rtx PROTO((tree));
 725 #endif
 726
 727 /* Indicate how an input argument register was promoted.  */
 728 extern rtx promoted_input_arg PROTO((int, enum machine_mode *, int *));
 729
 730 /* Return an rtx like arg but sans any constant terms.
 731    Returns the original rtx if it has no constant terms.
 732    The constant terms are added and stored via a second arg.  */
 733 extern rtx eliminate_constant_term PROTO((rtx, rtx *));
 734
 735 /* Convert arg to a valid memory address for specified machine mode,
 736    by emitting insns to perform arithmetic if nec.  */
 737 extern rtx memory_address PROTO((enum machine_mode, rtx));
 738
 739 /* Like `memory_address' but pretent `flag_force_addr' is 0.  */
 740 extern rtx memory_address_noforce PROTO((enum machine_mode, rtx));
 741
 742 /* Return a memory reference like MEMREF, but with its mode changed
 743    to MODE and its address changed to ADDR.
 744    (VOIDmode means don't change the mode.
 745    NULL for ADDR means don't change the address.)  */
 746 extern rtx change_address PROTO((rtx, enum machine_mode, rtx));
 747
 748 /* Return a memory reference like MEMREF, but which is known to have a
 749    valid address.  */
 750
 751 extern rtx validize_mem PROTO((rtx));
 752
 753 /* Assemble the static constant template for function entry trampolines.  */
 754 extern rtx assemble_trampoline_template PROTO((void));
 755
 756 /* Return 1 if two rtx's are equivalent in structure and elements.  */
 757 extern int rtx_equal_p PROTO((rtx, rtx));
 758
 759 /* Given rtx, return new rtx whose address won't be affected by
 760    any side effects.  It has been copied to a new temporary reg.  */
 761 extern rtx stabilize PROTO((rtx));
 762
 763 /* Given an rtx, copy all regs it refers to into new temps
 764    and return a modified copy that refers to the new temps.  */
 765 extern rtx copy_all_regs PROTO((rtx));
 766
 767 /* Copy given rtx to a new temp reg and return that.  */
 768 extern rtx copy_to_reg PROTO((rtx));
 769
 770 /* Like copy_to_reg but always make the reg Pmode.  */
 771 extern rtx copy_addr_to_reg PROTO((rtx));
 772
 773 /* Like copy_to_reg but always make the reg the specified mode MODE.  */
 774 extern rtx copy_to_mode_reg PROTO((enum machine_mode, rtx));
 775
 776 /* Copy given rtx to given temp reg and return that.  */
 777 extern rtx copy_to_suggested_reg PROTO((rtx, rtx, enum machine_mode));
 778
 779 /* Copy a value to a register if it isn't already a register.
 780    Args are mode (in case value is a constant) and the value.  */
 781 extern rtx force_reg PROTO((enum machine_mode, rtx));
 782
 783 /* Return given rtx, copied into a new temp reg if it was in memory.  */
 784 extern rtx force_not_mem PROTO((rtx));
 785
 786 #ifdef TREE_CODE
 787 /* Return mode and signedness to use when object is promoted.  */
 788 extern enum machine_mode promote_mode PROTO((tree, enum machine_mode,
 789                                              int *, int));
 790 #endif
 791
 792 /* Remove some bytes from the stack.  An rtx says how many.  */
 793 extern void adjust_stack PROTO((rtx));
 794
 795 /* Add some bytes to the stack.  An rtx says how many.  */
 796 extern void anti_adjust_stack PROTO((rtx));
 797
 798 /* This enum is used for the following two functions.  */
 799 enum save_level {SAVE_BLOCK, SAVE_FUNCTION, SAVE_NONLOCAL};
 800
 801 /* Save the stack pointer at the specified level.  */
 802 extern void emit_stack_save PROTO((enum save_level, rtx *, rtx));
 803
 804 /* Restore the stack pointer from a save area of the specified level.  */
 805 extern void emit_stack_restore PROTO((enum save_level, rtx, rtx));
 806
 807 /* Allocate some space on the stack dynamically and return its address.  An rtx
 808    says how many bytes.  */
 809 extern rtx allocate_dynamic_stack_space PROTO((rtx, rtx, int));
 810
 811 /* Emit code to copy function value to a new temp reg and return that reg.  */
 812 extern rtx function_value ();
 813
 814 /* Return an rtx that refers to the value returned by a library call
 815    in its original home.  This becomes invalid if any more code is emitted.  */
 816 extern rtx hard_libcall_value PROTO((enum machine_mode));
 817
 818 /* Given an rtx, return an rtx for a value rounded up to a multiple
 819    of STACK_BOUNDARY / BITS_PER_UNIT.  */
 820 extern rtx round_push PROTO((rtx));
 821
 822 extern void emit_block_move PROTO((rtx, rtx, rtx, int));
 823
 824 extern rtx store_bit_field PROTO((rtx, int, int, enum machine_mode, rtx, int, int));
 825 extern rtx extract_bit_field PROTO((rtx, int, int, int, rtx, enum machine_mode, enum machine_mode, int, int));
 826 extern rtx expand_mult PROTO((enum machine_mode, rtx, rtx, rtx, int));
 827 extern rtx expand_mult_add PROTO((rtx, rtx, rtx, rtx,enum machine_mode, int));
 828
 829 extern rtx assemble_static_space PROTO((int));
 830
 831 /* Hook called by expand_expr for language-specific tree codes.
 832    It is up to the language front end to install a hook
 833    if it has any such codes that expand_expr needs to know about.  */
 834 extern rtx (*lang_expand_expr) ();