gcc/expr.h

   1 /* Definitions for code generation pass of GNU compiler.
   2    Copyright (C) 1987-2013 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef GCC_EXPR_H
  21 #define GCC_EXPR_H
  22
  23 /* For inhibit_defer_pop */
  24 #include "function.h"
  25 /* For XEXP, GEN_INT, rtx_code */
  26 #include "rtl.h"
  27 /* For optimize_size */
  28 #include "flags.h"
  29 /* For host_integerp, tree_low_cst, fold_convert, size_binop, ssize_int,
  30    TREE_CODE, TYPE_SIZE, int_size_in_bytes,    */
  31 #include "tree.h"
  32 /* For GET_MODE_BITSIZE, word_mode */
  33 #include "machmode.h"
  34
  35 /* This is the 4th arg to `expand_expr'.
  36    EXPAND_STACK_PARM means we are possibly expanding a call param onto
  37    the stack.
  38    EXPAND_SUM means it is ok to return a PLUS rtx or MULT rtx.
  39    EXPAND_INITIALIZER is similar but also record any labels on forced_labels.
  40    EXPAND_CONST_ADDRESS means it is ok to return a MEM whose address
  41     is a constant that is not a legitimate address.
  42    EXPAND_WRITE means we are only going to write to the resulting rtx.
  43    EXPAND_MEMORY means we are interested in a memory result, even if
  44     the memory is constant and we could have propagated a constant value.  */
  45 enum expand_modifier {EXPAND_NORMAL = 0, EXPAND_STACK_PARM, EXPAND_SUM,
  46                       EXPAND_CONST_ADDRESS, EXPAND_INITIALIZER, EXPAND_WRITE,
  47                       EXPAND_MEMORY};
  48
  49 /* Prevent the compiler from deferring stack pops.  See
  50    inhibit_defer_pop for more information.  */
  51 #define NO_DEFER_POP (inhibit_defer_pop += 1)
  52
  53 /* Allow the compiler to defer stack pops.  See inhibit_defer_pop for
  54    more information.  */
  55 #define OK_DEFER_POP (inhibit_defer_pop -= 1)
  56 \f
  57 enum direction {none, upward, downward};
  58
  59 /* Structure to record the size of a sequence of arguments
  60    as the sum of a tree-expression and a constant.  This structure is
  61    also used to store offsets from the stack, which might be negative,
  62    so the variable part must be ssizetype, not sizetype.  */
  63
  64 struct args_size
  65 {
  66   HOST_WIDE_INT constant;
  67   tree var;
  68 };
  69
  70 /* Package up various arg related fields of struct args for
  71    locate_and_pad_parm.  */
  72 struct locate_and_pad_arg_data
  73 {
  74   /* Size of this argument on the stack, rounded up for any padding it
  75      gets.  If REG_PARM_STACK_SPACE is defined, then register parms are
  76      counted here, otherwise they aren't.  */
  77   struct args_size size;
  78   /* Offset of this argument from beginning of stack-args.  */
  79   struct args_size offset;
  80   /* Offset to the start of the stack slot.  Different from OFFSET
  81      if this arg pads downward.  */
  82   struct args_size slot_offset;
  83   /* The amount that the stack pointer needs to be adjusted to
  84      force alignment for the next argument.  */
  85   struct args_size alignment_pad;
  86   /* Which way we should pad this arg.  */
  87   enum direction where_pad;
  88   /* slot_offset is at least this aligned.  */
  89   unsigned int boundary;
  90 };
  91
  92 /* Add the value of the tree INC to the `struct args_size' TO.  */
  93
  94 #define ADD_PARM_SIZE(TO, INC)                                  \
  95 do {                                                            \
  96   tree inc = (INC);                                             \
  97   if (host_integerp (inc, 0))                                   \
  98     (TO).constant += tree_low_cst (inc, 0);                     \
  99   else if ((TO).var == 0)                                       \
 100     (TO).var = fold_convert (ssizetype, inc);                   \
 101   else                                                          \
 102     (TO).var = size_binop (PLUS_EXPR, (TO).var,                 \
 103                            fold_convert (ssizetype, inc));      \
 104 } while (0)
 105
 106 #define SUB_PARM_SIZE(TO, DEC)                                  \
 107 do {                                                            \
 108   tree dec = (DEC);                                             \
 109   if (host_integerp (dec, 0))                                   \
 110     (TO).constant -= tree_low_cst (dec, 0);                     \
 111   else if ((TO).var == 0)                                       \
 112     (TO).var = size_binop (MINUS_EXPR, ssize_int (0),           \
 113                            fold_convert (ssizetype, dec));      \
 114   else                                                          \
 115     (TO).var = size_binop (MINUS_EXPR, (TO).var,                \
 116                            fold_convert (ssizetype, dec));      \
 117 } while (0)
 118
 119 /* Convert the implicit sum in a `struct args_size' into a tree
 120    of type ssizetype.  */
 121 #define ARGS_SIZE_TREE(SIZE)                                    \
 122 ((SIZE).var == 0 ? ssize_int ((SIZE).constant)                  \
 123  : size_binop (PLUS_EXPR, fold_convert (ssizetype, (SIZE).var), \
 124                ssize_int ((SIZE).constant)))
 125
 126 /* Convert the implicit sum in a `struct args_size' into an rtx.  */
 127 #define ARGS_SIZE_RTX(SIZE)                                     \
 128 ((SIZE).var == 0 ? GEN_INT ((SIZE).constant)                    \
 129  : expand_normal (ARGS_SIZE_TREE (SIZE)))
 130
 131 \f
 132 /* This structure is used to pass around information about exploded
 133    unary, binary and trinary expressions between expand_expr_real_1 and
 134    friends.  */
 135 typedef struct separate_ops
 136 {
 137   enum tree_code code;
 138   location_t location;
 139   tree type;
 140   tree op0, op1, op2;
 141 } *sepops;
 142 \f
 143 /* Functions from optabs.c, commonly used, and without need for the optabs
 144    tables:  */
 145
 146 /* Passed to expand_simple_binop and expand_binop to say which options
 147    to try to use if the requested operation can't be open-coded on the
 148    requisite mode.  Either OPTAB_LIB or OPTAB_LIB_WIDEN says try using
 149    a library call.  Either OPTAB_WIDEN or OPTAB_LIB_WIDEN says try
 150    using a wider mode.  OPTAB_MUST_WIDEN says try widening and don't
 151    try anything else.  */
 152
 153 enum optab_methods
 154 {
 155   OPTAB_DIRECT,
 156   OPTAB_LIB,
 157   OPTAB_WIDEN,
 158   OPTAB_LIB_WIDEN,
 159   OPTAB_MUST_WIDEN
 160 };
 161
 162 /* Generate code for a simple binary or unary operation.  "Simple" in
 163    this case means "can be unambiguously described by a (mode, code)
 164    pair and mapped to a single optab."  */
 165 extern rtx expand_simple_binop (enum machine_mode, enum rtx_code, rtx,
 166                                 rtx, rtx, int, enum optab_methods);
 167 extern rtx expand_simple_unop (enum machine_mode, enum rtx_code, rtx, rtx,
 168                                int);
 169
 170 /* Report whether the machine description contains an insn which can
 171    perform the operation described by CODE and MODE.  */
 172 extern int have_insn_for (enum rtx_code, enum machine_mode);
 173
 174 /* Emit code to make a call to a constant function or a library call.  */
 175 extern void emit_libcall_block (rtx, rtx, rtx, rtx);
 176
 177 /* Create but don't emit one rtl instruction to perform certain operations.
 178    Modes must match; operands must meet the operation's predicates.
 179    Likewise for subtraction and for just copying.  */
 180 extern rtx gen_add2_insn (rtx, rtx);
 181 extern rtx gen_add3_insn (rtx, rtx, rtx);
 182 extern rtx gen_sub2_insn (rtx, rtx);
 183 extern rtx gen_sub3_insn (rtx, rtx, rtx);
 184 extern rtx gen_move_insn (rtx, rtx);
 185 extern int have_add2_insn (rtx, rtx);
 186 extern int have_sub2_insn (rtx, rtx);
 187
 188 /* Emit a pair of rtl insns to compare two rtx's and to jump
 189    to a label if the comparison is true.  */
 190 extern void emit_cmp_and_jump_insns (rtx, rtx, enum rtx_code, rtx,
 191                                      enum machine_mode, int, rtx, int prob=-1);
 192
 193 /* Generate code to indirectly jump to a location given in the rtx LOC.  */
 194 extern void emit_indirect_jump (rtx);
 195
 196 /* Generate a conditional trap instruction.  */
 197 extern rtx gen_cond_trap (enum rtx_code, rtx, rtx, rtx);
 198
 199 #include "insn-config.h"
 200
 201 #ifdef HAVE_conditional_move
 202 /* Emit a conditional move operation.  */
 203 rtx emit_conditional_move (rtx, enum rtx_code, rtx, rtx, enum machine_mode,
 204                            rtx, rtx, enum machine_mode, int);
 205
 206 /* Return nonzero if the conditional move is supported.  */
 207 int can_conditionally_move_p (enum machine_mode mode);
 208
 209 #endif
 210 rtx emit_conditional_add (rtx, enum rtx_code, rtx, rtx, enum machine_mode,
 211                           rtx, rtx, enum machine_mode, int);
 212
 213 rtx expand_sync_operation (rtx, rtx, enum rtx_code);
 214 rtx expand_sync_fetch_operation (rtx, rtx, enum rtx_code, bool, rtx);
 215 rtx expand_sync_lock_test_and_set (rtx, rtx, rtx);
 216
 217 rtx expand_atomic_exchange (rtx, rtx, rtx, enum memmodel);
 218 rtx expand_atomic_load (rtx, rtx, enum memmodel);
 219 rtx expand_atomic_store (rtx, rtx, enum memmodel, bool);
 220 rtx expand_atomic_fetch_op (rtx, rtx, rtx, enum rtx_code, enum memmodel,
 221                               bool);
 222 rtx expand_atomic_test_and_set (rtx, rtx, enum memmodel);
 223 rtx expand_atomic_clear (rtx, enum memmodel);
 224 void expand_atomic_thread_fence (enum memmodel);
 225 void expand_atomic_signal_fence (enum memmodel);
 226
 227 \f
 228 /* Functions from expmed.c:  */
 229
 230 /* Arguments MODE, RTX: return an rtx for the negation of that value.
 231    May emit insns.  */
 232 extern rtx negate_rtx (enum machine_mode, rtx);
 233
 234 /* Expand a logical AND operation.  */
 235 extern rtx expand_and (enum machine_mode, rtx, rtx, rtx);
 236
 237 /* Emit a store-flag operation.  */
 238 extern rtx emit_store_flag (rtx, enum rtx_code, rtx, rtx, enum machine_mode,
 239                             int, int);
 240
 241 /* Like emit_store_flag, but always succeeds.  */
 242 extern rtx emit_store_flag_force (rtx, enum rtx_code, rtx, rtx,
 243                                   enum machine_mode, int, int);
 244
 245 /* Choose a minimal N + 1 bit approximation to 1/D that can be used to
 246    replace division by D, and put the least significant N bits of the result
 247    in *MULTIPLIER_PTR and return the most significant bit.  */
 248 extern unsigned HOST_WIDE_INT choose_multiplier (unsigned HOST_WIDE_INT, int,
 249                                                  int, unsigned HOST_WIDE_INT *,
 250                                                  int *, int *);
 251 \f
 252 /* Functions from builtins.c:  */
 253 extern rtx expand_builtin (tree, rtx, rtx, enum machine_mode, int);
 254 extern tree std_build_builtin_va_list (void);
 255 extern tree std_fn_abi_va_list (tree);
 256 extern tree std_canonical_va_list_type (tree);
 257
 258 extern void std_expand_builtin_va_start (tree, rtx);
 259 extern rtx default_expand_builtin (tree, rtx, rtx, enum machine_mode, int);
 260 extern void expand_builtin_setjmp_setup (rtx, rtx);
 261 extern void expand_builtin_setjmp_receiver (rtx);
 262 extern rtx expand_builtin_saveregs (void);
 263 extern void expand_builtin_trap (void);
 264 extern rtx builtin_strncpy_read_str (void *, HOST_WIDE_INT, enum machine_mode);
 265 \f
 266 /* Functions from expr.c:  */
 267
 268 /* This is run during target initialization to set up which modes can be
 269    used directly in memory and to initialize the block move optab.  */
 270 extern void init_expr_target (void);
 271
 272 /* This is run at the start of compiling a function.  */
 273 extern void init_expr (void);
 274
 275 /* Emit some rtl insns to move data between rtx's, converting machine modes.
 276    Both modes must be floating or both fixed.  */
 277 extern void convert_move (rtx, rtx, int);
 278
 279 /* Convert an rtx to specified machine mode and return the result.  */
 280 extern rtx convert_to_mode (enum machine_mode, rtx, int);
 281
 282 /* Convert an rtx to MODE from OLDMODE and return the result.  */
 283 extern rtx convert_modes (enum machine_mode, enum machine_mode, rtx, int);
 284
 285 /* Emit code to move a block Y to a block X.  */
 286
 287 enum block_op_methods
 288 {
 289   BLOCK_OP_NORMAL,
 290   BLOCK_OP_NO_LIBCALL,
 291   BLOCK_OP_CALL_PARM,
 292   /* Like BLOCK_OP_NORMAL, but the libcall can be tail call optimized.  */
 293   BLOCK_OP_TAILCALL
 294 };
 295
 296 extern GTY(()) tree block_clear_fn;
 297 extern void init_block_move_fn (const char *);
 298 extern void init_block_clear_fn (const char *);
 299
 300 extern rtx emit_block_move (rtx, rtx, rtx, enum block_op_methods);
 301 extern rtx emit_block_move_via_libcall (rtx, rtx, rtx, bool);
 302 extern rtx emit_block_move_hints (rtx, rtx, rtx, enum block_op_methods,
 303                                   unsigned int, HOST_WIDE_INT);
 304 extern bool emit_storent_insn (rtx to, rtx from);
 305
 306 /* Copy all or part of a value X into registers starting at REGNO.
 307    The number of registers to be filled is NREGS.  */
 308 extern void move_block_to_reg (int, rtx, int, enum machine_mode);
 309
 310 /* Copy all or part of a BLKmode value X out of registers starting at REGNO.
 311    The number of registers to be filled is NREGS.  */
 312 extern void move_block_from_reg (int, rtx, int);
 313
 314 /* Generate a non-consecutive group of registers represented by a PARALLEL.  */
 315 extern rtx gen_group_rtx (rtx);
 316
 317 /* Load a BLKmode value into non-consecutive registers represented by a
 318    PARALLEL.  */
 319 extern void emit_group_load (rtx, rtx, tree, int);
 320
 321 /* Similarly, but load into new temporaries.  */
 322 extern rtx emit_group_load_into_temps (rtx, rtx, tree, int);
 323
 324 /* Move a non-consecutive group of registers represented by a PARALLEL into
 325    a non-consecutive group of registers represented by a PARALLEL.  */
 326 extern void emit_group_move (rtx, rtx);
 327
 328 /* Move a group of registers represented by a PARALLEL into pseudos.  */
 329 extern rtx emit_group_move_into_temps (rtx);
 330
 331 /* Store a BLKmode value from non-consecutive registers represented by a
 332    PARALLEL.  */
 333 extern void emit_group_store (rtx, rtx, tree, int);
 334
 335 extern rtx maybe_emit_group_store (rtx, tree);
 336
 337 /* Copy BLKmode object from a set of registers.  */
 338 extern void copy_blkmode_from_reg (rtx, rtx, tree);
 339
 340 /* Mark REG as holding a parameter for the next CALL_INSN.
 341    Mode is TYPE_MODE of the non-promoted parameter, or VOIDmode.  */
 342 extern void use_reg_mode (rtx *, rtx, enum machine_mode);
 343
 344 extern rtx copy_blkmode_to_reg (enum machine_mode, tree);
 345
 346 /* Mark REG as holding a parameter for the next CALL_INSN.  */
 347 static inline void
 348 use_reg (rtx *fusage, rtx reg)
 349 {
 350   use_reg_mode (fusage, reg, VOIDmode);
 351 }
 352
 353 /* Mark NREGS consecutive regs, starting at REGNO, as holding parameters
 354    for the next CALL_INSN.  */
 355 extern void use_regs (rtx *, int, int);
 356
 357 /* Mark a PARALLEL as holding a parameter for the next CALL_INSN.  */
 358 extern void use_group_regs (rtx *, rtx);
 359
 360 /* Write zeros through the storage of OBJECT.
 361    If OBJECT has BLKmode, SIZE is its length in bytes.  */
 362 extern rtx clear_storage (rtx, rtx, enum block_op_methods);
 363 extern rtx clear_storage_hints (rtx, rtx, enum block_op_methods,
 364                                 unsigned int, HOST_WIDE_INT);
 365 /* The same, but always output an library call.  */
 366 rtx set_storage_via_libcall (rtx, rtx, rtx, bool);
 367
 368 /* Expand a setmem pattern; return true if successful.  */
 369 extern bool set_storage_via_setmem (rtx, rtx, rtx, unsigned int,
 370                                     unsigned int, HOST_WIDE_INT);
 371
 372 extern unsigned HOST_WIDE_INT move_by_pieces_ninsns (unsigned HOST_WIDE_INT,
 373                                                      unsigned int,
 374                                                      unsigned int);
 375
 376 /* Return nonzero if it is desirable to store LEN bytes generated by
 377    CONSTFUN with several move instructions by store_by_pieces
 378    function.  CONSTFUNDATA is a pointer which will be passed as argument
 379    in every CONSTFUN call.
 380    ALIGN is maximum alignment we can assume.
 381    MEMSETP is true if this is a real memset/bzero, not a copy
 382    of a const string.  */
 383 extern int can_store_by_pieces (unsigned HOST_WIDE_INT,
 384                                 rtx (*) (void *, HOST_WIDE_INT,
 385                                          enum machine_mode),
 386                                 void *, unsigned int, bool);
 387
 388 /* Generate several move instructions to store LEN bytes generated by
 389    CONSTFUN to block TO.  (A MEM rtx with BLKmode).  CONSTFUNDATA is a
 390    pointer which will be passed as argument in every CONSTFUN call.
 391    ALIGN is maximum alignment we can assume.
 392    MEMSETP is true if this is a real memset/bzero, not a copy.
 393    Returns TO + LEN.  */
 394 extern rtx store_by_pieces (rtx, unsigned HOST_WIDE_INT,
 395                             rtx (*) (void *, HOST_WIDE_INT, enum machine_mode),
 396                             void *, unsigned int, bool, int);
 397
 398 /* Emit insns to set X from Y.  */
 399 extern rtx emit_move_insn (rtx, rtx);
 400
 401 /* Emit insns to set X from Y, with no frills.  */
 402 extern rtx emit_move_insn_1 (rtx, rtx);
 403
 404 extern rtx emit_move_complex_push (enum machine_mode, rtx, rtx);
 405 extern rtx emit_move_complex_parts (rtx, rtx);
 406
 407 /* Push a block of length SIZE (perhaps variable)
 408    and return an rtx to address the beginning of the block.  */
 409 extern rtx push_block (rtx, int, int);
 410
 411 /* Generate code to push something onto the stack, given its mode and type.  */
 412 extern void emit_push_insn (rtx, enum machine_mode, tree, rtx, unsigned int,
 413                             int, rtx, int, rtx, rtx, int, rtx);
 414
 415 /* Expand an assignment that stores the value of FROM into TO.  */
 416 extern void expand_assignment (tree, tree, bool);
 417
 418 /* Generate code for computing expression EXP,
 419    and storing the value into TARGET.
 420    If SUGGEST_REG is nonzero, copy the value through a register
 421    and return that register, if that is possible.  */
 422 extern rtx store_expr (tree, rtx, int, bool);
 423
 424 /* Given an rtx that may include add and multiply operations,
 425    generate them as insns and return a pseudo-reg containing the value.
 426    Useful after calling expand_expr with 1 as sum_ok.  */
 427 extern rtx force_operand (rtx, rtx);
 428
 429 /* Work horses for expand_expr.  */
 430 extern rtx expand_expr_real (tree, rtx, enum machine_mode,
 431                              enum expand_modifier, rtx *);
 432 extern rtx expand_expr_real_1 (tree, rtx, enum machine_mode,
 433                                enum expand_modifier, rtx *);
 434 extern rtx expand_expr_real_2 (sepops, rtx, enum machine_mode,
 435                                enum expand_modifier);
 436
 437 /* Generate code for computing expression EXP.
 438    An rtx for the computed value is returned.  The value is never null.
 439    In the case of a void EXP, const0_rtx is returned.  */
 440 static inline rtx
 441 expand_expr (tree exp, rtx target, enum machine_mode mode,
 442              enum expand_modifier modifier)
 443 {
 444   return expand_expr_real (exp, target, mode, modifier, NULL);
 445 }
 446
 447 static inline rtx
 448 expand_normal (tree exp)
 449 {
 450   return expand_expr_real (exp, NULL_RTX, VOIDmode, EXPAND_NORMAL, NULL);
 451 }
 452
 453 /* At the start of a function, record that we have no previously-pushed
 454    arguments waiting to be popped.  */
 455 extern void init_pending_stack_adjust (void);
 456
 457 /* Discard any pending stack adjustment.  */
 458 extern void discard_pending_stack_adjust (void);
 459
 460 /* When exiting from function, if safe, clear out any pending stack adjust
 461    so the adjustment won't get done.  */
 462 extern void clear_pending_stack_adjust (void);
 463
 464 /* Pop any previously-pushed arguments that have not been popped yet.  */
 465 extern void do_pending_stack_adjust (void);
 466
 467 /* Return the tree node and offset if a given argument corresponds to
 468    a string constant.  */
 469 extern tree string_constant (tree, tree *);
 470
 471 /* Generate code to evaluate EXP and jump to LABEL if the value is zero.  */
 472 extern void jumpifnot (tree, rtx, int);
 473 extern void jumpifnot_1 (enum tree_code, tree, tree, rtx, int);
 474
 475 /* Generate code to evaluate EXP and jump to LABEL if the value is nonzero.  */
 476 extern void jumpif (tree, rtx, int);
 477 extern void jumpif_1 (enum tree_code, tree, tree, rtx, int);
 478
 479 /* Generate code to evaluate EXP and jump to IF_FALSE_LABEL if
 480    the result is zero, or IF_TRUE_LABEL if the result is one.  */
 481 extern void do_jump (tree, rtx, rtx, int);
 482 extern void do_jump_1 (enum tree_code, tree, tree, rtx, rtx, int);
 483
 484 extern void do_compare_rtx_and_jump (rtx, rtx, enum rtx_code, int,
 485                                      enum machine_mode, rtx, rtx, rtx, int);
 486
 487 /* Two different ways of generating switch statements.  */
 488 extern int try_casesi (tree, tree, tree, tree, rtx, rtx, rtx, int);
 489 extern int try_tablejump (tree, tree, tree, tree, rtx, rtx, int);
 490
 491 /* Functions from alias.c */
 492 #include "alias.h"
 493
 494 \f
 495 /* rtl.h and tree.h were included.  */
 496 /* Return an rtx for the size in bytes of the value of an expr.  */
 497 extern rtx expr_size (tree);
 498
 499 /* Return a wide integer for the size in bytes of the value of EXP, or -1
 500    if the size can vary or is larger than an integer.  */
 501 extern HOST_WIDE_INT int_expr_size (tree);
 502
 503 /* Return an rtx that refers to the value returned by a function
 504    in its original home.  This becomes invalid if any more code is emitted.  */
 505 extern rtx hard_function_value (const_tree, const_tree, const_tree, int);
 506
 507 extern rtx prepare_call_address (tree, rtx, rtx, rtx *, int, int);
 508
 509 extern bool shift_return_value (enum machine_mode, bool, rtx);
 510
 511 extern rtx expand_call (tree, rtx, int);
 512
 513 extern void fixup_tail_calls (void);
 514
 515 #ifdef TREE_CODE
 516 extern rtx expand_variable_shift (enum tree_code, enum machine_mode,
 517                                   rtx, tree, rtx, int);
 518 extern rtx expand_shift (enum tree_code, enum machine_mode, rtx, int, rtx,
 519                              int);
 520 extern rtx expand_divmod (int, enum tree_code, enum machine_mode, rtx, rtx,
 521                           rtx, int);
 522 #endif
 523
 524 extern void locate_and_pad_parm (enum machine_mode, tree, int, int, tree,
 525                                  struct args_size *,
 526                                  struct locate_and_pad_arg_data *);
 527
 528 /* Return the CODE_LABEL rtx for a LABEL_DECL, creating it if necessary.  */
 529 extern rtx label_rtx (tree);
 530
 531 /* As label_rtx, but additionally the label is placed on the forced label
 532    list of its containing function (i.e. it is treated as reachable even
 533    if how is not obvious).  */
 534 extern rtx force_label_rtx (tree);
 535
 536 /* Return an rtx like arg but sans any constant terms.
 537    Returns the original rtx if it has no constant terms.
 538    The constant terms are added and stored via a second arg.  */
 539 extern rtx eliminate_constant_term (rtx, rtx *);
 540
 541 /* Convert arg to a valid memory address for specified machine mode that points
 542    to a specific named address space, by emitting insns to perform arithmetic
 543    if necessary.  */
 544 extern rtx memory_address_addr_space (enum machine_mode, rtx, addr_space_t);
 545
 546 /* Like memory_address_addr_space, except assume the memory address points to
 547    the generic named address space.  */
 548 #define memory_address(MODE,RTX) \
 549         memory_address_addr_space ((MODE), (RTX), ADDR_SPACE_GENERIC)
 550
 551 /* Return a memory reference like MEMREF, but with its mode changed
 552    to MODE and its address changed to ADDR.
 553    (VOIDmode means don't change the mode.
 554    NULL for ADDR means don't change the address.)  */
 555 extern rtx change_address (rtx, enum machine_mode, rtx);
 556
 557 /* Return a memory reference like MEMREF, but with its mode changed
 558    to MODE and its address offset by OFFSET bytes.  */
 559 #define adjust_address(MEMREF, MODE, OFFSET) \
 560   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 0, 0)
 561
 562 /* Likewise, but the reference is not required to be valid.  */
 563 #define adjust_address_nv(MEMREF, MODE, OFFSET) \
 564   adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 0, 0)
 565
 566 /* Return a memory reference like MEMREF, but with its mode changed
 567    to MODE and its address offset by OFFSET bytes.  Assume that it's
 568    for a bitfield and conservatively drop the underlying object if we
 569    cannot be sure to stay within its bounds.  */
 570 #define adjust_bitfield_address(MEMREF, MODE, OFFSET) \
 571   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, 0)
 572
 573 /* As for adjust_bitfield_address, but specify that the width of
 574    BLKmode accesses is SIZE bytes.  */
 575 #define adjust_bitfield_address_size(MEMREF, MODE, OFFSET, SIZE) \
 576   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, SIZE)
 577
 578 /* Likewise, but the reference is not required to be valid.  */
 579 #define adjust_bitfield_address_nv(MEMREF, MODE, OFFSET) \
 580   adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 1, 0)
 581
 582 /* Return a memory reference like MEMREF, but with its mode changed
 583    to MODE and its address changed to ADDR, which is assumed to be
 584    increased by OFFSET bytes from MEMREF.  */
 585 #define adjust_automodify_address(MEMREF, MODE, ADDR, OFFSET) \
 586   adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 1)
 587
 588 /* Likewise, but the reference is not required to be valid.  */
 589 #define adjust_automodify_address_nv(MEMREF, MODE, ADDR, OFFSET) \
 590   adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 0)
 591
 592 extern rtx adjust_address_1 (rtx, enum machine_mode, HOST_WIDE_INT, int, int,
 593                              int, HOST_WIDE_INT);
 594 extern rtx adjust_automodify_address_1 (rtx, enum machine_mode, rtx,
 595                                         HOST_WIDE_INT, int);
 596
 597 /* Return a memory reference like MEMREF, but whose address is changed by
 598    adding OFFSET, an RTX, to it.  POW2 is the highest power of two factor
 599    known to be in OFFSET (possibly 1).  */
 600 extern rtx offset_address (rtx, rtx, unsigned HOST_WIDE_INT);
 601
 602 /* Definitions from emit-rtl.c */
 603 #include "emit-rtl.h"
 604
 605 /* Return a memory reference like MEMREF, but with its mode widened to
 606    MODE and adjusted by OFFSET.  */
 607 extern rtx widen_memory_access (rtx, enum machine_mode, HOST_WIDE_INT);
 608
 609 /* Return a memory reference like MEMREF, but which is known to have a
 610    valid address.  */
 611 extern rtx validize_mem (rtx);
 612
 613 extern rtx use_anchored_address (rtx);
 614
 615 /* Given REF, a MEM, and T, either the type of X or the expression
 616    corresponding to REF, set the memory attributes.  OBJECTP is nonzero
 617    if we are making a new object of this type.  */
 618 extern void set_mem_attributes (rtx, tree, int);
 619
 620 /* Similar, except that BITPOS has not yet been applied to REF, so if
 621    we alter MEM_OFFSET according to T then we should subtract BITPOS
 622    expecting that it'll be added back in later.  */
 623 extern void set_mem_attributes_minus_bitpos (rtx, tree, int, HOST_WIDE_INT);
 624
 625 /* Return OFFSET if XEXP (MEM, 0) - OFFSET is known to be ALIGN
 626    bits aligned for 0 <= OFFSET < ALIGN / BITS_PER_UNIT, or
 627    -1 if not known.  */
 628 extern int get_mem_align_offset (rtx, unsigned int);
 629
 630 /* Assemble the static constant template for function entry trampolines.  */
 631 extern rtx assemble_trampoline_template (void);
 632
 633 /* Copy given rtx to a new temp reg and return that.  */
 634 extern rtx copy_to_reg (rtx);
 635
 636 /* Like copy_to_reg but always make the reg Pmode.  */
 637 extern rtx copy_addr_to_reg (rtx);
 638
 639 /* Like copy_to_reg but always make the reg the specified mode MODE.  */
 640 extern rtx copy_to_mode_reg (enum machine_mode, rtx);
 641
 642 /* Copy given rtx to given temp reg and return that.  */
 643 extern rtx copy_to_suggested_reg (rtx, rtx, enum machine_mode);
 644
 645 /* Copy a value to a register if it isn't already a register.
 646    Args are mode (in case value is a constant) and the value.  */
 647 extern rtx force_reg (enum machine_mode, rtx);
 648
 649 /* Return given rtx, copied into a new temp reg if it was in memory.  */
 650 extern rtx force_not_mem (rtx);
 651
 652 /* Return mode and signedness to use when an argument or result in the
 653    given mode is promoted.  */
 654 extern enum machine_mode promote_function_mode (const_tree, enum machine_mode, int *,
 655                                                 const_tree, int);
 656
 657 /* Return mode and signedness to use when an object in the given mode
 658    is promoted.  */
 659 extern enum machine_mode promote_mode (const_tree, enum machine_mode, int *);
 660
 661 /* Return mode and signedness to use when object is promoted.  */
 662 enum machine_mode promote_decl_mode (const_tree, int *);
 663
 664 /* Remove some bytes from the stack.  An rtx says how many.  */
 665 extern void adjust_stack (rtx);
 666
 667 /* Add some bytes to the stack.  An rtx says how many.  */
 668 extern void anti_adjust_stack (rtx);
 669
 670 /* Add some bytes to the stack while probing it.  An rtx says how many. */
 671 extern void anti_adjust_stack_and_probe (rtx, bool);
 672
 673 /* This enum is used for the following two functions.  */
 674 enum save_level {SAVE_BLOCK, SAVE_FUNCTION, SAVE_NONLOCAL};
 675
 676 /* Save the stack pointer at the specified level.  */
 677 extern void emit_stack_save (enum save_level, rtx *);
 678
 679 /* Restore the stack pointer from a save area of the specified level.  */
 680 extern void emit_stack_restore (enum save_level, rtx);
 681
 682 /* Invoke emit_stack_save for the nonlocal_goto_save_area.  */
 683 extern void update_nonlocal_goto_save_area (void);
 684
 685 /* Allocate some space on the stack dynamically and return its address.  */
 686 extern rtx allocate_dynamic_stack_space (rtx, unsigned, unsigned, bool);
 687
 688 /* Emit one stack probe at ADDRESS, an address within the stack.  */
 689 extern void emit_stack_probe (rtx);
 690
 691 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
 692    FIRST is a constant and size is a Pmode RTX.  These are offsets from
 693    the current stack pointer.  STACK_GROWS_DOWNWARD says whether to add
 694    or subtract them from the stack pointer.  */
 695 extern void probe_stack_range (HOST_WIDE_INT, rtx);
 696
 697 /* Return an rtx that refers to the value returned by a library call
 698    in its original home.  This becomes invalid if any more code is emitted.  */
 699 extern rtx hard_libcall_value (enum machine_mode, rtx);
 700
 701 extern void store_bit_field (rtx, unsigned HOST_WIDE_INT,
 702                              unsigned HOST_WIDE_INT,
 703                              unsigned HOST_WIDE_INT,
 704                              unsigned HOST_WIDE_INT,
 705                              enum machine_mode, rtx);
 706 extern rtx extract_bit_field (rtx, unsigned HOST_WIDE_INT,
 707                               unsigned HOST_WIDE_INT, int, bool, rtx,
 708                               enum machine_mode, enum machine_mode);
 709 extern rtx extract_low_bits (enum machine_mode, enum machine_mode, rtx);
 710 extern rtx expand_mult (enum machine_mode, rtx, rtx, rtx, int);
 711 extern rtx expand_mult_highpart_adjust (enum machine_mode, rtx, rtx, rtx, rtx, int);
 712
 713 extern rtx assemble_static_space (unsigned HOST_WIDE_INT);
 714 extern int safe_from_p (const_rtx, tree, int);
 715 extern bool split_comparison (enum rtx_code, enum machine_mode,
 716                               enum rtx_code *, enum rtx_code *);
 717
 718 /* Call this once to initialize the contents of the optabs
 719    appropriately for the current target machine.  */
 720 extern void init_optabs (void);
 721 extern void init_all_optabs (struct target_optabs *);
 722
 723 /* Call this to initialize an optab function entry.  */
 724 extern rtx init_one_libfunc (const char *);
 725 extern rtx set_user_assembler_libfunc (const char *, const char *);
 726
 727 /* Build a decl for a libfunc named NAME. */
 728 extern tree build_libfunc_function (const char *);
 729
 730 /* Get the personality libfunc for a function decl.  */
 731 rtx get_personality_function (tree);
 732
 733
 734 /* In stmt.c */
 735
 736 /* Expand a GIMPLE_SWITCH statement.  */
 737 extern void expand_case (gimple);
 738
 739 /* Like expand_case but special-case for SJLJ exception dispatching.  */
 740 extern void expand_sjlj_dispatch_table (rtx, vec<tree> );
 741
 742 #endif /* GCC_EXPR_H */