gcc/expr.h

   1 /* Definitions for code generation pass of GNU compiler.
   2    Copyright (C) 1987-2014 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 tree_fits_[su]hwi_p, tree_to_[su]hwi, fold_convert, size_binop,
  30    ssize_int, TREE_CODE, TYPE_SIZE, int_size_in_bytes,    */
  31 #include "tree-core.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     or the memory is unaligned on a STRICT_ALIGNMENT target.  */
  46 enum expand_modifier {EXPAND_NORMAL = 0, EXPAND_STACK_PARM, EXPAND_SUM,
  47                       EXPAND_CONST_ADDRESS, EXPAND_INITIALIZER, EXPAND_WRITE,
  48                       EXPAND_MEMORY};
  49
  50 /* Prevent the compiler from deferring stack pops.  See
  51    inhibit_defer_pop for more information.  */
  52 #define NO_DEFER_POP (inhibit_defer_pop += 1)
  53
  54 /* Allow the compiler to defer stack pops.  See inhibit_defer_pop for
  55    more information.  */
  56 #define OK_DEFER_POP (inhibit_defer_pop -= 1)
  57 \f
  58 enum direction {none, upward, downward};
  59
  60 /* Structure to record the size of a sequence of arguments
  61    as the sum of a tree-expression and a constant.  This structure is
  62    also used to store offsets from the stack, which might be negative,
  63    so the variable part must be ssizetype, not sizetype.  */
  64
  65 struct args_size
  66 {
  67   HOST_WIDE_INT constant;
  68   tree var;
  69 };
  70
  71 /* Package up various arg related fields of struct args for
  72    locate_and_pad_parm.  */
  73 struct locate_and_pad_arg_data
  74 {
  75   /* Size of this argument on the stack, rounded up for any padding it
  76      gets.  If REG_PARM_STACK_SPACE is defined, then register parms are
  77      counted here, otherwise they aren't.  */
  78   struct args_size size;
  79   /* Offset of this argument from beginning of stack-args.  */
  80   struct args_size offset;
  81   /* Offset to the start of the stack slot.  Different from OFFSET
  82      if this arg pads downward.  */
  83   struct args_size slot_offset;
  84   /* The amount that the stack pointer needs to be adjusted to
  85      force alignment for the next argument.  */
  86   struct args_size alignment_pad;
  87   /* Which way we should pad this arg.  */
  88   enum direction where_pad;
  89   /* slot_offset is at least this aligned.  */
  90   unsigned int boundary;
  91 };
  92
  93 /* Add the value of the tree INC to the `struct args_size' TO.  */
  94
  95 #define ADD_PARM_SIZE(TO, INC)                                  \
  96 do {                                                            \
  97   tree inc = (INC);                                             \
  98   if (tree_fits_shwi_p (inc))                                   \
  99     (TO).constant += tree_to_shwi (inc);                        \
 100   else if ((TO).var == 0)                                       \
 101     (TO).var = fold_convert (ssizetype, inc);                   \
 102   else                                                          \
 103     (TO).var = size_binop (PLUS_EXPR, (TO).var,                 \
 104                            fold_convert (ssizetype, inc));      \
 105 } while (0)
 106
 107 #define SUB_PARM_SIZE(TO, DEC)                                  \
 108 do {                                                            \
 109   tree dec = (DEC);                                             \
 110   if (tree_fits_shwi_p (dec))                                   \
 111     (TO).constant -= tree_to_shwi (dec);                        \
 112   else if ((TO).var == 0)                                       \
 113     (TO).var = size_binop (MINUS_EXPR, ssize_int (0),           \
 114                            fold_convert (ssizetype, dec));      \
 115   else                                                          \
 116     (TO).var = size_binop (MINUS_EXPR, (TO).var,                \
 117                            fold_convert (ssizetype, dec));      \
 118 } while (0)
 119
 120 /* Convert the implicit sum in a `struct args_size' into a tree
 121    of type ssizetype.  */
 122 #define ARGS_SIZE_TREE(SIZE)                                    \
 123 ((SIZE).var == 0 ? ssize_int ((SIZE).constant)                  \
 124  : size_binop (PLUS_EXPR, fold_convert (ssizetype, (SIZE).var), \
 125                ssize_int ((SIZE).constant)))
 126
 127 /* Convert the implicit sum in a `struct args_size' into an rtx.  */
 128 #define ARGS_SIZE_RTX(SIZE)                                     \
 129 ((SIZE).var == 0 ? GEN_INT ((SIZE).constant)                    \
 130  : expand_normal (ARGS_SIZE_TREE (SIZE)))
 131
 132 \f
 133 /* This structure is used to pass around information about exploded
 134    unary, binary and trinary expressions between expand_expr_real_1 and
 135    friends.  */
 136 typedef struct separate_ops
 137 {
 138   enum tree_code code;
 139   location_t location;
 140   tree type;
 141   tree op0, op1, op2;
 142 } *sepops;
 143 \f
 144 /* Functions from optabs.c, commonly used, and without need for the optabs
 145    tables:  */
 146
 147 /* Passed to expand_simple_binop and expand_binop to say which options
 148    to try to use if the requested operation can't be open-coded on the
 149    requisite mode.  Either OPTAB_LIB or OPTAB_LIB_WIDEN says try using
 150    a library call.  Either OPTAB_WIDEN or OPTAB_LIB_WIDEN says try
 151    using a wider mode.  OPTAB_MUST_WIDEN says try widening and don't
 152    try anything else.  */
 153
 154 enum optab_methods
 155 {
 156   OPTAB_DIRECT,
 157   OPTAB_LIB,
 158   OPTAB_WIDEN,
 159   OPTAB_LIB_WIDEN,
 160   OPTAB_MUST_WIDEN
 161 };
 162
 163 /* Generate code for a simple binary or unary operation.  "Simple" in
 164    this case means "can be unambiguously described by a (mode, code)
 165    pair and mapped to a single optab."  */
 166 extern rtx expand_simple_binop (enum machine_mode, enum rtx_code, rtx,
 167                                 rtx, rtx, int, enum optab_methods);
 168 extern rtx expand_simple_unop (enum machine_mode, enum rtx_code, rtx, rtx,
 169                                int);
 170
 171 /* Report whether the machine description contains an insn which can
 172    perform the operation described by CODE and MODE.  */
 173 extern int have_insn_for (enum rtx_code, enum machine_mode);
 174
 175 /* Emit code to make a call to a constant function or a library call.  */
 176 extern void emit_libcall_block (rtx, rtx, rtx, rtx);
 177
 178 /* Create but don't emit one rtl instruction to perform certain operations.
 179    Modes must match; operands must meet the operation's predicates.
 180    Likewise for subtraction and for just copying.  */
 181 extern rtx gen_add2_insn (rtx, rtx);
 182 extern rtx gen_add3_insn (rtx, rtx, rtx);
 183 extern rtx gen_addptr3_insn (rtx, rtx, rtx);
 184 extern rtx gen_sub2_insn (rtx, rtx);
 185 extern rtx gen_sub3_insn (rtx, rtx, rtx);
 186 extern rtx gen_move_insn (rtx, rtx);
 187 extern int have_add2_insn (rtx, rtx);
 188 extern int have_addptr3_insn (rtx, rtx, rtx);
 189 extern int have_sub2_insn (rtx, rtx);
 190
 191 /* Emit a pair of rtl insns to compare two rtx's and to jump
 192    to a label if the comparison is true.  */
 193 extern void emit_cmp_and_jump_insns (rtx, rtx, enum rtx_code, rtx,
 194                                      enum machine_mode, int, rtx, int prob=-1);
 195
 196 /* Generate code to indirectly jump to a location given in the rtx LOC.  */
 197 extern void emit_indirect_jump (rtx);
 198
 199 /* Generate a conditional trap instruction.  */
 200 extern rtx gen_cond_trap (enum rtx_code, rtx, rtx, rtx);
 201
 202 #include "insn-config.h"
 203
 204 #ifdef HAVE_conditional_move
 205 /* Emit a conditional move operation.  */
 206 rtx emit_conditional_move (rtx, enum rtx_code, rtx, rtx, enum machine_mode,
 207                            rtx, rtx, enum machine_mode, int);
 208
 209 /* Return nonzero if the conditional move is supported.  */
 210 int can_conditionally_move_p (enum machine_mode mode);
 211
 212 #endif
 213 rtx emit_conditional_add (rtx, enum rtx_code, rtx, rtx, enum machine_mode,
 214                           rtx, rtx, enum machine_mode, int);
 215
 216 rtx expand_sync_operation (rtx, rtx, enum rtx_code);
 217 rtx expand_sync_fetch_operation (rtx, rtx, enum rtx_code, bool, rtx);
 218 rtx expand_sync_lock_test_and_set (rtx, rtx, rtx);
 219
 220 rtx expand_atomic_exchange (rtx, rtx, rtx, enum memmodel);
 221 rtx expand_atomic_load (rtx, rtx, enum memmodel);
 222 rtx expand_atomic_store (rtx, rtx, enum memmodel, bool);
 223 rtx expand_atomic_fetch_op (rtx, rtx, rtx, enum rtx_code, enum memmodel,
 224                               bool);
 225 rtx expand_atomic_test_and_set (rtx, rtx, enum memmodel);
 226 rtx expand_atomic_clear (rtx, enum memmodel);
 227 void expand_atomic_thread_fence (enum memmodel);
 228 void expand_atomic_signal_fence (enum memmodel);
 229
 230 \f
 231 /* Functions from expmed.c:  */
 232
 233 /* Arguments MODE, RTX: return an rtx for the negation of that value.
 234    May emit insns.  */
 235 extern rtx negate_rtx (enum machine_mode, rtx);
 236
 237 /* Expand a logical AND operation.  */
 238 extern rtx expand_and (enum machine_mode, rtx, rtx, rtx);
 239
 240 /* Emit a store-flag operation.  */
 241 extern rtx emit_store_flag (rtx, enum rtx_code, rtx, rtx, enum machine_mode,
 242                             int, int);
 243
 244 /* Like emit_store_flag, but always succeeds.  */
 245 extern rtx emit_store_flag_force (rtx, enum rtx_code, rtx, rtx,
 246                                   enum machine_mode, int, int);
 247
 248 /* Choose a minimal N + 1 bit approximation to 1/D that can be used to
 249    replace division by D, and put the least significant N bits of the result
 250    in *MULTIPLIER_PTR and return the most significant bit.  */
 251 extern unsigned HOST_WIDE_INT choose_multiplier (unsigned HOST_WIDE_INT, int,
 252                                                  int, unsigned HOST_WIDE_INT *,
 253                                                  int *, int *);
 254 \f
 255 /* Functions from expr.c:  */
 256
 257 /* This is run during target initialization to set up which modes can be
 258    used directly in memory and to initialize the block move optab.  */
 259 extern void init_expr_target (void);
 260
 261 /* This is run at the start of compiling a function.  */
 262 extern void init_expr (void);
 263
 264 /* Emit some rtl insns to move data between rtx's, converting machine modes.
 265    Both modes must be floating or both fixed.  */
 266 extern void convert_move (rtx, rtx, int);
 267
 268 /* Convert an rtx to specified machine mode and return the result.  */
 269 extern rtx convert_to_mode (enum machine_mode, rtx, int);
 270
 271 /* Convert an rtx to MODE from OLDMODE and return the result.  */
 272 extern rtx convert_modes (enum machine_mode, enum machine_mode, rtx, int);
 273
 274 /* Emit code to move a block Y to a block X.  */
 275
 276 enum block_op_methods
 277 {
 278   BLOCK_OP_NORMAL,
 279   BLOCK_OP_NO_LIBCALL,
 280   BLOCK_OP_CALL_PARM,
 281   /* Like BLOCK_OP_NORMAL, but the libcall can be tail call optimized.  */
 282   BLOCK_OP_TAILCALL
 283 };
 284
 285 extern GTY(()) tree block_clear_fn;
 286 extern void init_block_move_fn (const char *);
 287 extern void init_block_clear_fn (const char *);
 288
 289 extern rtx emit_block_move (rtx, rtx, rtx, enum block_op_methods);
 290 extern rtx emit_block_move_via_libcall (rtx, rtx, rtx, bool);
 291 extern rtx emit_block_move_hints (rtx, rtx, rtx, enum block_op_methods,
 292                                   unsigned int, HOST_WIDE_INT,
 293                                   unsigned HOST_WIDE_INT,
 294                                   unsigned HOST_WIDE_INT,
 295                                   unsigned HOST_WIDE_INT);
 296 extern bool emit_storent_insn (rtx to, rtx from);
 297
 298 /* Copy all or part of a value X into registers starting at REGNO.
 299    The number of registers to be filled is NREGS.  */
 300 extern void move_block_to_reg (int, rtx, int, enum machine_mode);
 301
 302 /* Copy all or part of a BLKmode value X out of registers starting at REGNO.
 303    The number of registers to be filled is NREGS.  */
 304 extern void move_block_from_reg (int, rtx, int);
 305
 306 /* Generate a non-consecutive group of registers represented by a PARALLEL.  */
 307 extern rtx gen_group_rtx (rtx);
 308
 309 /* Load a BLKmode value into non-consecutive registers represented by a
 310    PARALLEL.  */
 311 extern void emit_group_load (rtx, rtx, tree, int);
 312
 313 /* Similarly, but load into new temporaries.  */
 314 extern rtx emit_group_load_into_temps (rtx, rtx, tree, int);
 315
 316 /* Move a non-consecutive group of registers represented by a PARALLEL into
 317    a non-consecutive group of registers represented by a PARALLEL.  */
 318 extern void emit_group_move (rtx, rtx);
 319
 320 /* Move a group of registers represented by a PARALLEL into pseudos.  */
 321 extern rtx emit_group_move_into_temps (rtx);
 322
 323 /* Store a BLKmode value from non-consecutive registers represented by a
 324    PARALLEL.  */
 325 extern void emit_group_store (rtx, rtx, tree, int);
 326
 327 extern rtx maybe_emit_group_store (rtx, tree);
 328
 329 /* Copy BLKmode object from a set of registers.  */
 330 extern void copy_blkmode_from_reg (rtx, rtx, tree);
 331
 332 /* Mark REG as holding a parameter for the next CALL_INSN.
 333    Mode is TYPE_MODE of the non-promoted parameter, or VOIDmode.  */
 334 extern void use_reg_mode (rtx *, rtx, enum machine_mode);
 335 extern void clobber_reg_mode (rtx *, rtx, enum machine_mode);
 336
 337 extern rtx copy_blkmode_to_reg (enum machine_mode, tree);
 338
 339 /* Mark REG as holding a parameter for the next CALL_INSN.  */
 340 static inline void
 341 use_reg (rtx *fusage, rtx reg)
 342 {
 343   use_reg_mode (fusage, reg, VOIDmode);
 344 }
 345
 346 /* Mark REG as clobbered by the call with FUSAGE as CALL_INSN_FUNCTION_USAGE.  */
 347 static inline void
 348 clobber_reg (rtx *fusage, rtx reg)
 349 {
 350   clobber_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                                 unsigned HOST_WIDE_INT,
 366                                 unsigned HOST_WIDE_INT,
 367                                 unsigned HOST_WIDE_INT);
 368 /* The same, but always output an library call.  */
 369 rtx set_storage_via_libcall (rtx, rtx, rtx, bool);
 370
 371 /* Expand a setmem pattern; return true if successful.  */
 372 extern bool set_storage_via_setmem (rtx, rtx, rtx, unsigned int,
 373                                     unsigned int, HOST_WIDE_INT,
 374                                     unsigned HOST_WIDE_INT,
 375                                     unsigned HOST_WIDE_INT,
 376                                     unsigned HOST_WIDE_INT);
 377
 378 extern unsigned HOST_WIDE_INT move_by_pieces_ninsns (unsigned HOST_WIDE_INT,
 379                                                      unsigned int,
 380                                                      unsigned int);
 381
 382 /* Return nonzero if it is desirable to store LEN bytes generated by
 383    CONSTFUN with several move instructions by store_by_pieces
 384    function.  CONSTFUNDATA is a pointer which will be passed as argument
 385    in every CONSTFUN call.
 386    ALIGN is maximum alignment we can assume.
 387    MEMSETP is true if this is a real memset/bzero, not a copy
 388    of a const string.  */
 389 extern int can_store_by_pieces (unsigned HOST_WIDE_INT,
 390                                 rtx (*) (void *, HOST_WIDE_INT,
 391                                          enum machine_mode),
 392                                 void *, unsigned int, bool);
 393
 394 /* Generate several move instructions to store LEN bytes generated by
 395    CONSTFUN to block TO.  (A MEM rtx with BLKmode).  CONSTFUNDATA is a
 396    pointer which will be passed as argument in every CONSTFUN call.
 397    ALIGN is maximum alignment we can assume.
 398    MEMSETP is true if this is a real memset/bzero, not a copy.
 399    Returns TO + LEN.  */
 400 extern rtx store_by_pieces (rtx, unsigned HOST_WIDE_INT,
 401                             rtx (*) (void *, HOST_WIDE_INT, enum machine_mode),
 402                             void *, unsigned int, bool, int);
 403
 404 /* Emit insns to set X from Y.  */
 405 extern rtx emit_move_insn (rtx, rtx);
 406
 407 /* Emit insns to set X from Y, with no frills.  */
 408 extern rtx emit_move_insn_1 (rtx, rtx);
 409
 410 extern rtx emit_move_complex_push (enum machine_mode, rtx, rtx);
 411 extern rtx emit_move_complex_parts (rtx, rtx);
 412 extern rtx emit_move_resolve_push (enum machine_mode, rtx);
 413
 414 /* Push a block of length SIZE (perhaps variable)
 415    and return an rtx to address the beginning of the block.  */
 416 extern rtx push_block (rtx, int, int);
 417
 418 /* Generate code to push something onto the stack, given its mode and type.  */
 419 extern void emit_push_insn (rtx, enum machine_mode, tree, rtx, unsigned int,
 420                             int, rtx, int, rtx, rtx, int, rtx);
 421
 422 /* Expand an assignment that stores the value of FROM into TO.  */
 423 extern void expand_assignment (tree, tree, bool);
 424
 425 /* Generate code for computing expression EXP,
 426    and storing the value into TARGET.
 427    If SUGGEST_REG is nonzero, copy the value through a register
 428    and return that register, if that is possible.  */
 429 extern rtx store_expr (tree, rtx, int, bool);
 430
 431 /* Given an rtx that may include add and multiply operations,
 432    generate them as insns and return a pseudo-reg containing the value.
 433    Useful after calling expand_expr with 1 as sum_ok.  */
 434 extern rtx force_operand (rtx, rtx);
 435
 436 /* Work horses for expand_expr.  */
 437 extern rtx expand_expr_real (tree, rtx, enum machine_mode,
 438                              enum expand_modifier, rtx *, bool);
 439 extern rtx expand_expr_real_1 (tree, rtx, enum machine_mode,
 440                                enum expand_modifier, rtx *, bool);
 441 extern rtx expand_expr_real_2 (sepops, rtx, enum machine_mode,
 442                                enum expand_modifier);
 443
 444 /* Generate code for computing expression EXP.
 445    An rtx for the computed value is returned.  The value is never null.
 446    In the case of a void EXP, const0_rtx is returned.  */
 447 static inline rtx
 448 expand_expr (tree exp, rtx target, enum machine_mode mode,
 449              enum expand_modifier modifier)
 450 {
 451   return expand_expr_real (exp, target, mode, modifier, NULL, false);
 452 }
 453
 454 static inline rtx
 455 expand_normal (tree exp)
 456 {
 457   return expand_expr_real (exp, NULL_RTX, VOIDmode, EXPAND_NORMAL, NULL, false);
 458 }
 459
 460 /* At the start of a function, record that we have no previously-pushed
 461    arguments waiting to be popped.  */
 462 extern void init_pending_stack_adjust (void);
 463
 464 /* Discard any pending stack adjustment.  */
 465 extern void discard_pending_stack_adjust (void);
 466
 467 /* When exiting from function, if safe, clear out any pending stack adjust
 468    so the adjustment won't get done.  */
 469 extern void clear_pending_stack_adjust (void);
 470
 471 /* Pop any previously-pushed arguments that have not been popped yet.  */
 472 extern void do_pending_stack_adjust (void);
 473
 474 /* Struct for saving/restoring of pending_stack_adjust/stack_pointer_delta
 475    values.  */
 476
 477 struct saved_pending_stack_adjust
 478 {
 479   /* Saved value of pending_stack_adjust.  */
 480   int x_pending_stack_adjust;
 481
 482   /* Saved value of stack_pointer_delta.  */
 483   int x_stack_pointer_delta;
 484 };
 485
 486 /* Remember pending_stack_adjust/stack_pointer_delta.
 487    To be used around code that may call do_pending_stack_adjust (),
 488    but the generated code could be discarded e.g. using delete_insns_since.  */
 489
 490 extern void save_pending_stack_adjust (saved_pending_stack_adjust *);
 491
 492 /* Restore the saved pending_stack_adjust/stack_pointer_delta.  */
 493
 494 extern void restore_pending_stack_adjust (saved_pending_stack_adjust *);
 495
 496 /* Return the tree node and offset if a given argument corresponds to
 497    a string constant.  */
 498 extern tree string_constant (tree, tree *);
 499
 500 /* Generate code to evaluate EXP and jump to LABEL if the value is zero.  */
 501 extern void jumpifnot (tree, rtx, int);
 502 extern void jumpifnot_1 (enum tree_code, tree, tree, rtx, int);
 503
 504 /* Generate code to evaluate EXP and jump to LABEL if the value is nonzero.  */
 505 extern void jumpif (tree, rtx, int);
 506 extern void jumpif_1 (enum tree_code, tree, tree, rtx, int);
 507
 508 /* Generate code to evaluate EXP and jump to IF_FALSE_LABEL if
 509    the result is zero, or IF_TRUE_LABEL if the result is one.  */
 510 extern void do_jump (tree, rtx, rtx, int);
 511 extern void do_jump_1 (enum tree_code, tree, tree, rtx, rtx, int);
 512
 513 extern void do_compare_rtx_and_jump (rtx, rtx, enum rtx_code, int,
 514                                      enum machine_mode, rtx, rtx, rtx, int);
 515
 516 /* Two different ways of generating switch statements.  */
 517 extern int try_casesi (tree, tree, tree, tree, rtx, rtx, rtx, int);
 518 extern int try_tablejump (tree, tree, tree, tree, rtx, rtx, int);
 519
 520 /* Functions from alias.c */
 521 #include "alias.h"
 522
 523 \f
 524 /* rtl.h and tree.h were included.  */
 525 /* Return an rtx for the size in bytes of the value of an expr.  */
 526 extern rtx expr_size (tree);
 527
 528 /* Return a wide integer for the size in bytes of the value of EXP, or -1
 529    if the size can vary or is larger than an integer.  */
 530 extern HOST_WIDE_INT int_expr_size (tree);
 531
 532 /* Return an rtx that refers to the value returned by a function
 533    in its original home.  This becomes invalid if any more code is emitted.  */
 534 extern rtx hard_function_value (const_tree, const_tree, const_tree, int);
 535
 536 extern rtx prepare_call_address (tree, rtx, rtx, rtx *, int, int);
 537
 538 extern bool shift_return_value (enum machine_mode, bool, rtx);
 539
 540 extern rtx expand_call (tree, rtx, int);
 541
 542 extern void fixup_tail_calls (void);
 543
 544 #ifdef TREE_CODE
 545 extern rtx expand_variable_shift (enum tree_code, enum machine_mode,
 546                                   rtx, tree, rtx, int);
 547 extern rtx expand_shift (enum tree_code, enum machine_mode, rtx, int, rtx,
 548                              int);
 549 extern rtx expand_divmod (int, enum tree_code, enum machine_mode, rtx, rtx,
 550                           rtx, int);
 551 #endif
 552
 553 extern void locate_and_pad_parm (enum machine_mode, tree, int, int, int,
 554                                  tree, struct args_size *,
 555                                  struct locate_and_pad_arg_data *);
 556
 557 /* Return the CODE_LABEL rtx for a LABEL_DECL, creating it if necessary.  */
 558 extern rtx label_rtx (tree);
 559
 560 /* As label_rtx, but additionally the label is placed on the forced label
 561    list of its containing function (i.e. it is treated as reachable even
 562    if how is not obvious).  */
 563 extern rtx force_label_rtx (tree);
 564
 565 /* Return an rtx like arg but sans any constant terms.
 566    Returns the original rtx if it has no constant terms.
 567    The constant terms are added and stored via a second arg.  */
 568 extern rtx eliminate_constant_term (rtx, rtx *);
 569
 570 /* Convert arg to a valid memory address for specified machine mode that points
 571    to a specific named address space, by emitting insns to perform arithmetic
 572    if necessary.  */
 573 extern rtx memory_address_addr_space (enum machine_mode, rtx, addr_space_t);
 574
 575 /* Like memory_address_addr_space, except assume the memory address points to
 576    the generic named address space.  */
 577 #define memory_address(MODE,RTX) \
 578         memory_address_addr_space ((MODE), (RTX), ADDR_SPACE_GENERIC)
 579
 580 /* Return a memory reference like MEMREF, but with its mode changed
 581    to MODE and its address changed to ADDR.
 582    (VOIDmode means don't change the mode.
 583    NULL for ADDR means don't change the address.)  */
 584 extern rtx change_address (rtx, enum machine_mode, rtx);
 585
 586 /* Return a memory reference like MEMREF, but with its mode changed
 587    to MODE and its address offset by OFFSET bytes.  */
 588 #define adjust_address(MEMREF, MODE, OFFSET) \
 589   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 0, 0)
 590
 591 /* Likewise, but the reference is not required to be valid.  */
 592 #define adjust_address_nv(MEMREF, MODE, OFFSET) \
 593   adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 0, 0)
 594
 595 /* Return a memory reference like MEMREF, but with its mode changed
 596    to MODE and its address offset by OFFSET bytes.  Assume that it's
 597    for a bitfield and conservatively drop the underlying object if we
 598    cannot be sure to stay within its bounds.  */
 599 #define adjust_bitfield_address(MEMREF, MODE, OFFSET) \
 600   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, 0)
 601
 602 /* As for adjust_bitfield_address, but specify that the width of
 603    BLKmode accesses is SIZE bytes.  */
 604 #define adjust_bitfield_address_size(MEMREF, MODE, OFFSET, SIZE) \
 605   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, SIZE)
 606
 607 /* Likewise, but the reference is not required to be valid.  */
 608 #define adjust_bitfield_address_nv(MEMREF, MODE, OFFSET) \
 609   adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 1, 0)
 610
 611 /* Return a memory reference like MEMREF, but with its mode changed
 612    to MODE and its address changed to ADDR, which is assumed to be
 613    increased by OFFSET bytes from MEMREF.  */
 614 #define adjust_automodify_address(MEMREF, MODE, ADDR, OFFSET) \
 615   adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 1)
 616
 617 /* Likewise, but the reference is not required to be valid.  */
 618 #define adjust_automodify_address_nv(MEMREF, MODE, ADDR, OFFSET) \
 619   adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 0)
 620
 621 extern rtx adjust_address_1 (rtx, enum machine_mode, HOST_WIDE_INT, int, int,
 622                              int, HOST_WIDE_INT);
 623 extern rtx adjust_automodify_address_1 (rtx, enum machine_mode, rtx,
 624                                         HOST_WIDE_INT, int);
 625
 626 /* Return a memory reference like MEMREF, but whose address is changed by
 627    adding OFFSET, an RTX, to it.  POW2 is the highest power of two factor
 628    known to be in OFFSET (possibly 1).  */
 629 extern rtx offset_address (rtx, rtx, unsigned HOST_WIDE_INT);
 630
 631 /* Definitions from emit-rtl.c */
 632 #include "emit-rtl.h"
 633
 634 /* Return a memory reference like MEMREF, but with its mode widened to
 635    MODE and adjusted by OFFSET.  */
 636 extern rtx widen_memory_access (rtx, enum machine_mode, HOST_WIDE_INT);
 637
 638 /* Return a memory reference like MEMREF, but which is known to have a
 639    valid address.  */
 640 extern rtx validize_mem (rtx);
 641
 642 extern rtx use_anchored_address (rtx);
 643
 644 /* Given REF, a MEM, and T, either the type of X or the expression
 645    corresponding to REF, set the memory attributes.  OBJECTP is nonzero
 646    if we are making a new object of this type.  */
 647 extern void set_mem_attributes (rtx, tree, int);
 648
 649 /* Similar, except that BITPOS has not yet been applied to REF, so if
 650    we alter MEM_OFFSET according to T then we should subtract BITPOS
 651    expecting that it'll be added back in later.  */
 652 extern void set_mem_attributes_minus_bitpos (rtx, tree, int, HOST_WIDE_INT);
 653
 654 /* Return OFFSET if XEXP (MEM, 0) - OFFSET is known to be ALIGN
 655    bits aligned for 0 <= OFFSET < ALIGN / BITS_PER_UNIT, or
 656    -1 if not known.  */
 657 extern int get_mem_align_offset (rtx, unsigned int);
 658
 659 /* Assemble the static constant template for function entry trampolines.  */
 660 extern rtx assemble_trampoline_template (void);
 661
 662 /* Copy given rtx to a new temp reg and return that.  */
 663 extern rtx copy_to_reg (rtx);
 664
 665 /* Like copy_to_reg but always make the reg Pmode.  */
 666 extern rtx copy_addr_to_reg (rtx);
 667
 668 /* Like copy_to_reg but always make the reg the specified mode MODE.  */
 669 extern rtx copy_to_mode_reg (enum machine_mode, rtx);
 670
 671 /* Copy given rtx to given temp reg and return that.  */
 672 extern rtx copy_to_suggested_reg (rtx, rtx, enum machine_mode);
 673
 674 /* Copy a value to a register if it isn't already a register.
 675    Args are mode (in case value is a constant) and the value.  */
 676 extern rtx force_reg (enum machine_mode, rtx);
 677
 678 /* Return given rtx, copied into a new temp reg if it was in memory.  */
 679 extern rtx force_not_mem (rtx);
 680
 681 /* Return mode and signedness to use when an argument or result in the
 682    given mode is promoted.  */
 683 extern enum machine_mode promote_function_mode (const_tree, enum machine_mode, int *,
 684                                                 const_tree, int);
 685
 686 /* Return mode and signedness to use when an object in the given mode
 687    is promoted.  */
 688 extern enum machine_mode promote_mode (const_tree, enum machine_mode, int *);
 689
 690 /* Return mode and signedness to use when object is promoted.  */
 691 enum machine_mode promote_decl_mode (const_tree, int *);
 692
 693 /* Remove some bytes from the stack.  An rtx says how many.  */
 694 extern void adjust_stack (rtx);
 695
 696 /* Add some bytes to the stack.  An rtx says how many.  */
 697 extern void anti_adjust_stack (rtx);
 698
 699 /* Add some bytes to the stack while probing it.  An rtx says how many. */
 700 extern void anti_adjust_stack_and_probe (rtx, bool);
 701
 702 /* This enum is used for the following two functions.  */
 703 enum save_level {SAVE_BLOCK, SAVE_FUNCTION, SAVE_NONLOCAL};
 704
 705 /* Save the stack pointer at the specified level.  */
 706 extern void emit_stack_save (enum save_level, rtx *);
 707
 708 /* Restore the stack pointer from a save area of the specified level.  */
 709 extern void emit_stack_restore (enum save_level, rtx);
 710
 711 /* Invoke emit_stack_save for the nonlocal_goto_save_area.  */
 712 extern void update_nonlocal_goto_save_area (void);
 713
 714 /* Allocate some space on the stack dynamically and return its address.  */
 715 extern rtx allocate_dynamic_stack_space (rtx, unsigned, unsigned, bool);
 716
 717 /* Emit one stack probe at ADDRESS, an address within the stack.  */
 718 extern void emit_stack_probe (rtx);
 719
 720 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
 721    FIRST is a constant and size is a Pmode RTX.  These are offsets from
 722    the current stack pointer.  STACK_GROWS_DOWNWARD says whether to add
 723    or subtract them from the stack pointer.  */
 724 extern void probe_stack_range (HOST_WIDE_INT, rtx);
 725
 726 /* Return an rtx that refers to the value returned by a library call
 727    in its original home.  This becomes invalid if any more code is emitted.  */
 728 extern rtx hard_libcall_value (enum machine_mode, rtx);
 729
 730 extern void store_bit_field (rtx, unsigned HOST_WIDE_INT,
 731                              unsigned HOST_WIDE_INT,
 732                              unsigned HOST_WIDE_INT,
 733                              unsigned HOST_WIDE_INT,
 734                              enum machine_mode, rtx);
 735 extern rtx extract_bit_field (rtx, unsigned HOST_WIDE_INT,
 736                               unsigned HOST_WIDE_INT, int, rtx,
 737                               enum machine_mode, enum machine_mode);
 738 extern rtx extract_low_bits (enum machine_mode, enum machine_mode, rtx);
 739 extern rtx expand_mult (enum machine_mode, rtx, rtx, rtx, int);
 740 extern rtx expand_mult_highpart_adjust (enum machine_mode, rtx, rtx, rtx, rtx, int);
 741
 742 extern rtx assemble_static_space (unsigned HOST_WIDE_INT);
 743 extern int safe_from_p (const_rtx, tree, int);
 744 extern bool split_comparison (enum rtx_code, enum machine_mode,
 745                               enum rtx_code *, enum rtx_code *);
 746
 747 /* Call this once to initialize the contents of the optabs
 748    appropriately for the current target machine.  */
 749 extern void init_optabs (void);
 750 extern void init_all_optabs (struct target_optabs *);
 751
 752 /* Call this to initialize an optab function entry.  */
 753 extern rtx init_one_libfunc (const char *);
 754 extern rtx set_user_assembler_libfunc (const char *, const char *);
 755
 756 /* Build a decl for a libfunc named NAME. */
 757 extern tree build_libfunc_function (const char *);
 758
 759 /* Get the personality libfunc for a function decl.  */
 760 rtx get_personality_function (tree);
 761
 762
 763 /* In stmt.c */
 764
 765 /* Expand a GIMPLE_SWITCH statement.  */
 766 extern void expand_case (gimple);
 767
 768 /* Like expand_case but special-case for SJLJ exception dispatching.  */
 769 extern void expand_sjlj_dispatch_table (rtx, vec<tree> );
 770
 771 /* Determine whether the LEN bytes can be moved by using several move
 772    instructions.  Return nonzero if a call to move_by_pieces should
 773    succeed.  */
 774 extern int can_move_by_pieces (unsigned HOST_WIDE_INT, unsigned int);
 775
 776 extern unsigned HOST_WIDE_INT highest_pow2_factor (const_tree);
 777 bool array_at_struct_end_p (tree);
 778
 779 /* Return a tree of sizetype representing the size, in bytes, of the element
 780    of EXP, an ARRAY_REF or an ARRAY_RANGE_REF.  */
 781 extern tree array_ref_element_size (tree);
 782
 783 extern bool categorize_ctor_elements (const_tree, HOST_WIDE_INT *,
 784                                       HOST_WIDE_INT *, bool *);
 785
 786 /* Return a tree representing the offset, in bytes, of the field referenced
 787    by EXP.  This does not include any offset in DECL_FIELD_BIT_OFFSET.  */
 788 extern tree component_ref_field_offset (tree);
 789
 790 #endif /* GCC_EXPR_H */