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 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 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 (tree_fits_shwi_p (inc))                                   \
  98     (TO).constant += tree_to_shwi (inc);                        \
  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 (tree_fits_shwi_p (dec))                                   \
 110     (TO).constant -= tree_to_shwi (dec);                        \
 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                                   unsigned HOST_WIDE_INT,
 305                                   unsigned HOST_WIDE_INT,
 306                                   unsigned HOST_WIDE_INT);
 307 extern bool emit_storent_insn (rtx to, rtx from);
 308
 309 /* Copy all or part of a value X into registers starting at REGNO.
 310    The number of registers to be filled is NREGS.  */
 311 extern void move_block_to_reg (int, rtx, int, enum machine_mode);
 312
 313 /* Copy all or part of a BLKmode value X out of registers starting at REGNO.
 314    The number of registers to be filled is NREGS.  */
 315 extern void move_block_from_reg (int, rtx, int);
 316
 317 /* Generate a non-consecutive group of registers represented by a PARALLEL.  */
 318 extern rtx gen_group_rtx (rtx);
 319
 320 /* Load a BLKmode value into non-consecutive registers represented by a
 321    PARALLEL.  */
 322 extern void emit_group_load (rtx, rtx, tree, int);
 323
 324 /* Similarly, but load into new temporaries.  */
 325 extern rtx emit_group_load_into_temps (rtx, rtx, tree, int);
 326
 327 /* Move a non-consecutive group of registers represented by a PARALLEL into
 328    a non-consecutive group of registers represented by a PARALLEL.  */
 329 extern void emit_group_move (rtx, rtx);
 330
 331 /* Move a group of registers represented by a PARALLEL into pseudos.  */
 332 extern rtx emit_group_move_into_temps (rtx);
 333
 334 /* Store a BLKmode value from non-consecutive registers represented by a
 335    PARALLEL.  */
 336 extern void emit_group_store (rtx, rtx, tree, int);
 337
 338 extern rtx maybe_emit_group_store (rtx, tree);
 339
 340 /* Copy BLKmode object from a set of registers.  */
 341 extern void copy_blkmode_from_reg (rtx, rtx, tree);
 342
 343 /* Mark REG as holding a parameter for the next CALL_INSN.
 344    Mode is TYPE_MODE of the non-promoted parameter, or VOIDmode.  */
 345 extern void use_reg_mode (rtx *, rtx, enum machine_mode);
 346
 347 extern rtx copy_blkmode_to_reg (enum machine_mode, tree);
 348
 349 /* Mark REG as holding a parameter for the next CALL_INSN.  */
 350 static inline void
 351 use_reg (rtx *fusage, rtx reg)
 352 {
 353   use_reg_mode (fusage, reg, VOIDmode);
 354 }
 355
 356 /* Mark NREGS consecutive regs, starting at REGNO, as holding parameters
 357    for the next CALL_INSN.  */
 358 extern void use_regs (rtx *, int, int);
 359
 360 /* Mark a PARALLEL as holding a parameter for the next CALL_INSN.  */
 361 extern void use_group_regs (rtx *, rtx);
 362
 363 /* Write zeros through the storage of OBJECT.
 364    If OBJECT has BLKmode, SIZE is its length in bytes.  */
 365 extern rtx clear_storage (rtx, rtx, enum block_op_methods);
 366 extern rtx clear_storage_hints (rtx, rtx, enum block_op_methods,
 367                                 unsigned int, HOST_WIDE_INT,
 368                                 unsigned HOST_WIDE_INT,
 369                                 unsigned HOST_WIDE_INT,
 370                                 unsigned HOST_WIDE_INT);
 371 /* The same, but always output an library call.  */
 372 rtx set_storage_via_libcall (rtx, rtx, rtx, bool);
 373
 374 /* Expand a setmem pattern; return true if successful.  */
 375 extern bool set_storage_via_setmem (rtx, rtx, rtx, unsigned int,
 376                                     unsigned int, HOST_WIDE_INT,
 377                                     unsigned HOST_WIDE_INT,
 378                                     unsigned HOST_WIDE_INT,
 379                                     unsigned HOST_WIDE_INT);
 380
 381 extern unsigned HOST_WIDE_INT move_by_pieces_ninsns (unsigned HOST_WIDE_INT,
 382                                                      unsigned int,
 383                                                      unsigned int);
 384
 385 /* Return nonzero if it is desirable to store LEN bytes generated by
 386    CONSTFUN with several move instructions by store_by_pieces
 387    function.  CONSTFUNDATA is a pointer which will be passed as argument
 388    in every CONSTFUN call.
 389    ALIGN is maximum alignment we can assume.
 390    MEMSETP is true if this is a real memset/bzero, not a copy
 391    of a const string.  */
 392 extern int can_store_by_pieces (unsigned HOST_WIDE_INT,
 393                                 rtx (*) (void *, HOST_WIDE_INT,
 394                                          enum machine_mode),
 395                                 void *, unsigned int, bool);
 396
 397 /* Generate several move instructions to store LEN bytes generated by
 398    CONSTFUN to block TO.  (A MEM rtx with BLKmode).  CONSTFUNDATA is a
 399    pointer which will be passed as argument in every CONSTFUN call.
 400    ALIGN is maximum alignment we can assume.
 401    MEMSETP is true if this is a real memset/bzero, not a copy.
 402    Returns TO + LEN.  */
 403 extern rtx store_by_pieces (rtx, unsigned HOST_WIDE_INT,
 404                             rtx (*) (void *, HOST_WIDE_INT, enum machine_mode),
 405                             void *, unsigned int, bool, int);
 406
 407 /* Emit insns to set X from Y.  */
 408 extern rtx emit_move_insn (rtx, rtx);
 409
 410 /* Emit insns to set X from Y, with no frills.  */
 411 extern rtx emit_move_insn_1 (rtx, rtx);
 412
 413 extern rtx emit_move_complex_push (enum machine_mode, rtx, rtx);
 414 extern rtx emit_move_complex_parts (rtx, rtx);
 415
 416 /* Push a block of length SIZE (perhaps variable)
 417    and return an rtx to address the beginning of the block.  */
 418 extern rtx push_block (rtx, int, int);
 419
 420 /* Generate code to push something onto the stack, given its mode and type.  */
 421 extern void emit_push_insn (rtx, enum machine_mode, tree, rtx, unsigned int,
 422                             int, rtx, int, rtx, rtx, int, rtx);
 423
 424 /* Expand an assignment that stores the value of FROM into TO.  */
 425 extern void expand_assignment (tree, tree, bool);
 426
 427 /* Generate code for computing expression EXP,
 428    and storing the value into TARGET.
 429    If SUGGEST_REG is nonzero, copy the value through a register
 430    and return that register, if that is possible.  */
 431 extern rtx store_expr (tree, rtx, int, bool);
 432
 433 /* Given an rtx that may include add and multiply operations,
 434    generate them as insns and return a pseudo-reg containing the value.
 435    Useful after calling expand_expr with 1 as sum_ok.  */
 436 extern rtx force_operand (rtx, rtx);
 437
 438 /* Work horses for expand_expr.  */
 439 extern rtx expand_expr_real (tree, rtx, enum machine_mode,
 440                              enum expand_modifier, rtx *);
 441 extern rtx expand_expr_real_1 (tree, rtx, enum machine_mode,
 442                                enum expand_modifier, rtx *);
 443 extern rtx expand_expr_real_2 (sepops, rtx, enum machine_mode,
 444                                enum expand_modifier);
 445
 446 /* Generate code for computing expression EXP.
 447    An rtx for the computed value is returned.  The value is never null.
 448    In the case of a void EXP, const0_rtx is returned.  */
 449 static inline rtx
 450 expand_expr (tree exp, rtx target, enum machine_mode mode,
 451              enum expand_modifier modifier)
 452 {
 453   return expand_expr_real (exp, target, mode, modifier, NULL);
 454 }
 455
 456 static inline rtx
 457 expand_normal (tree exp)
 458 {
 459   return expand_expr_real (exp, NULL_RTX, VOIDmode, EXPAND_NORMAL, NULL);
 460 }
 461
 462 /* At the start of a function, record that we have no previously-pushed
 463    arguments waiting to be popped.  */
 464 extern void init_pending_stack_adjust (void);
 465
 466 /* Discard any pending stack adjustment.  */
 467 extern void discard_pending_stack_adjust (void);
 468
 469 /* When exiting from function, if safe, clear out any pending stack adjust
 470    so the adjustment won't get done.  */
 471 extern void clear_pending_stack_adjust (void);
 472
 473 /* Pop any previously-pushed arguments that have not been popped yet.  */
 474 extern void do_pending_stack_adjust (void);
 475
 476 /* Struct for saving/restoring of pending_stack_adjust/stack_pointer_delta
 477    values.  */
 478
 479 struct saved_pending_stack_adjust
 480 {
 481   /* Saved value of pending_stack_adjust.  */
 482   int x_pending_stack_adjust;
 483
 484   /* Saved value of stack_pointer_delta.  */
 485   int x_stack_pointer_delta;
 486 };
 487
 488 /* Remember pending_stack_adjust/stack_pointer_delta.
 489    To be used around code that may call do_pending_stack_adjust (),
 490    but the generated code could be discarded e.g. using delete_insns_since.  */
 491
 492 extern void save_pending_stack_adjust (saved_pending_stack_adjust *);
 493
 494 /* Restore the saved pending_stack_adjust/stack_pointer_delta.  */
 495
 496 extern void restore_pending_stack_adjust (saved_pending_stack_adjust *);
 497
 498 /* Return the tree node and offset if a given argument corresponds to
 499    a string constant.  */
 500 extern tree string_constant (tree, tree *);
 501
 502 /* If X is a sum, return a new sum like X but lacking any constant terms.  */
 503 extern tree tree_expr_size (const_tree);
 504
 505 /* Generate code to evaluate EXP and jump to LABEL if the value is zero.  */
 506 extern void jumpifnot (tree, rtx, int);
 507 extern void jumpifnot_1 (enum tree_code, tree, tree, rtx, int);
 508
 509 /* Generate code to evaluate EXP and jump to LABEL if the value is nonzero.  */
 510 extern void jumpif (tree, rtx, int);
 511 extern void jumpif_1 (enum tree_code, tree, tree, rtx, int);
 512
 513 /* Generate code to evaluate EXP and jump to IF_FALSE_LABEL if
 514    the result is zero, or IF_TRUE_LABEL if the result is one.  */
 515 extern void do_jump (tree, rtx, rtx, int);
 516 extern void do_jump_1 (enum tree_code, tree, tree, rtx, rtx, int);
 517
 518 extern void do_compare_rtx_and_jump (rtx, rtx, enum rtx_code, int,
 519                                      enum machine_mode, rtx, rtx, rtx, int);
 520
 521 /* Two different ways of generating switch statements.  */
 522 extern int try_casesi (tree, tree, tree, tree, rtx, rtx, rtx, int);
 523 extern int try_tablejump (tree, tree, tree, tree, rtx, rtx, int);
 524
 525 /* Functions from alias.c */
 526 #include "alias.h"
 527
 528 \f
 529 /* rtl.h and tree.h were included.  */
 530 /* Return an rtx for the size in bytes of the value of an expr.  */
 531 extern rtx expr_size (tree);
 532
 533 /* Return a wide integer for the size in bytes of the value of EXP, or -1
 534    if the size can vary or is larger than an integer.  */
 535 extern HOST_WIDE_INT int_expr_size (tree);
 536
 537 /* Return an rtx that refers to the value returned by a function
 538    in its original home.  This becomes invalid if any more code is emitted.  */
 539 extern rtx hard_function_value (const_tree, const_tree, const_tree, int);
 540
 541 extern rtx prepare_call_address (tree, rtx, rtx, rtx *, int, int);
 542
 543 extern bool shift_return_value (enum machine_mode, bool, rtx);
 544
 545 extern rtx expand_call (tree, rtx, int);
 546
 547 extern void fixup_tail_calls (void);
 548
 549 #ifdef TREE_CODE
 550 extern rtx expand_variable_shift (enum tree_code, enum machine_mode,
 551                                   rtx, tree, rtx, int);
 552 extern rtx expand_shift (enum tree_code, enum machine_mode, rtx, int, rtx,
 553                              int);
 554 extern rtx expand_divmod (int, enum tree_code, enum machine_mode, rtx, rtx,
 555                           rtx, int);
 556 #endif
 557
 558 extern void locate_and_pad_parm (enum machine_mode, tree, int, int, int,
 559                                  tree, struct args_size *,
 560                                  struct locate_and_pad_arg_data *);
 561
 562 /* Return the CODE_LABEL rtx for a LABEL_DECL, creating it if necessary.  */
 563 extern rtx label_rtx (tree);
 564
 565 /* As label_rtx, but additionally the label is placed on the forced label
 566    list of its containing function (i.e. it is treated as reachable even
 567    if how is not obvious).  */
 568 extern rtx force_label_rtx (tree);
 569
 570 /* Return an rtx like arg but sans any constant terms.
 571    Returns the original rtx if it has no constant terms.
 572    The constant terms are added and stored via a second arg.  */
 573 extern rtx eliminate_constant_term (rtx, rtx *);
 574
 575 /* Convert arg to a valid memory address for specified machine mode that points
 576    to a specific named address space, by emitting insns to perform arithmetic
 577    if necessary.  */
 578 extern rtx memory_address_addr_space (enum machine_mode, rtx, addr_space_t);
 579
 580 /* Like memory_address_addr_space, except assume the memory address points to
 581    the generic named address space.  */
 582 #define memory_address(MODE,RTX) \
 583         memory_address_addr_space ((MODE), (RTX), ADDR_SPACE_GENERIC)
 584
 585 /* Return a memory reference like MEMREF, but with its mode changed
 586    to MODE and its address changed to ADDR.
 587    (VOIDmode means don't change the mode.
 588    NULL for ADDR means don't change the address.)  */
 589 extern rtx change_address (rtx, enum machine_mode, rtx);
 590
 591 /* Return a memory reference like MEMREF, but with its mode changed
 592    to MODE and its address offset by OFFSET bytes.  */
 593 #define adjust_address(MEMREF, MODE, OFFSET) \
 594   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 0, 0)
 595
 596 /* Likewise, but the reference is not required to be valid.  */
 597 #define adjust_address_nv(MEMREF, MODE, OFFSET) \
 598   adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 0, 0)
 599
 600 /* Return a memory reference like MEMREF, but with its mode changed
 601    to MODE and its address offset by OFFSET bytes.  Assume that it's
 602    for a bitfield and conservatively drop the underlying object if we
 603    cannot be sure to stay within its bounds.  */
 604 #define adjust_bitfield_address(MEMREF, MODE, OFFSET) \
 605   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, 0)
 606
 607 /* As for adjust_bitfield_address, but specify that the width of
 608    BLKmode accesses is SIZE bytes.  */
 609 #define adjust_bitfield_address_size(MEMREF, MODE, OFFSET, SIZE) \
 610   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, SIZE)
 611
 612 /* Likewise, but the reference is not required to be valid.  */
 613 #define adjust_bitfield_address_nv(MEMREF, MODE, OFFSET) \
 614   adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 1, 0)
 615
 616 /* Return a memory reference like MEMREF, but with its mode changed
 617    to MODE and its address changed to ADDR, which is assumed to be
 618    increased by OFFSET bytes from MEMREF.  */
 619 #define adjust_automodify_address(MEMREF, MODE, ADDR, OFFSET) \
 620   adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 1)
 621
 622 /* Likewise, but the reference is not required to be valid.  */
 623 #define adjust_automodify_address_nv(MEMREF, MODE, ADDR, OFFSET) \
 624   adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 0)
 625
 626 extern rtx adjust_address_1 (rtx, enum machine_mode, HOST_WIDE_INT, int, int,
 627                              int, HOST_WIDE_INT);
 628 extern rtx adjust_automodify_address_1 (rtx, enum machine_mode, rtx,
 629                                         HOST_WIDE_INT, int);
 630
 631 /* Return a memory reference like MEMREF, but whose address is changed by
 632    adding OFFSET, an RTX, to it.  POW2 is the highest power of two factor
 633    known to be in OFFSET (possibly 1).  */
 634 extern rtx offset_address (rtx, rtx, unsigned HOST_WIDE_INT);
 635
 636 /* Definitions from emit-rtl.c */
 637 #include "emit-rtl.h"
 638
 639 /* Return a memory reference like MEMREF, but with its mode widened to
 640    MODE and adjusted by OFFSET.  */
 641 extern rtx widen_memory_access (rtx, enum machine_mode, HOST_WIDE_INT);
 642
 643 /* Return a memory reference like MEMREF, but which is known to have a
 644    valid address.  */
 645 extern rtx validize_mem (rtx);
 646
 647 extern rtx use_anchored_address (rtx);
 648
 649 /* Given REF, a MEM, and T, either the type of X or the expression
 650    corresponding to REF, set the memory attributes.  OBJECTP is nonzero
 651    if we are making a new object of this type.  */
 652 extern void set_mem_attributes (rtx, tree, int);
 653
 654 /* Similar, except that BITPOS has not yet been applied to REF, so if
 655    we alter MEM_OFFSET according to T then we should subtract BITPOS
 656    expecting that it'll be added back in later.  */
 657 extern void set_mem_attributes_minus_bitpos (rtx, tree, int, HOST_WIDE_INT);
 658
 659 /* Return OFFSET if XEXP (MEM, 0) - OFFSET is known to be ALIGN
 660    bits aligned for 0 <= OFFSET < ALIGN / BITS_PER_UNIT, or
 661    -1 if not known.  */
 662 extern int get_mem_align_offset (rtx, unsigned int);
 663
 664 /* Assemble the static constant template for function entry trampolines.  */
 665 extern rtx assemble_trampoline_template (void);
 666
 667 /* Copy given rtx to a new temp reg and return that.  */
 668 extern rtx copy_to_reg (rtx);
 669
 670 /* Like copy_to_reg but always make the reg Pmode.  */
 671 extern rtx copy_addr_to_reg (rtx);
 672
 673 /* Like copy_to_reg but always make the reg the specified mode MODE.  */
 674 extern rtx copy_to_mode_reg (enum machine_mode, rtx);
 675
 676 /* Copy given rtx to given temp reg and return that.  */
 677 extern rtx copy_to_suggested_reg (rtx, rtx, enum machine_mode);
 678
 679 /* Copy a value to a register if it isn't already a register.
 680    Args are mode (in case value is a constant) and the value.  */
 681 extern rtx force_reg (enum machine_mode, rtx);
 682
 683 /* Return given rtx, copied into a new temp reg if it was in memory.  */
 684 extern rtx force_not_mem (rtx);
 685
 686 /* Return mode and signedness to use when an argument or result in the
 687    given mode is promoted.  */
 688 extern enum machine_mode promote_function_mode (const_tree, enum machine_mode, int *,
 689                                                 const_tree, int);
 690
 691 /* Return mode and signedness to use when an object in the given mode
 692    is promoted.  */
 693 extern enum machine_mode promote_mode (const_tree, enum machine_mode, int *);
 694
 695 /* Return mode and signedness to use when object is promoted.  */
 696 enum machine_mode promote_decl_mode (const_tree, int *);
 697
 698 /* Remove some bytes from the stack.  An rtx says how many.  */
 699 extern void adjust_stack (rtx);
 700
 701 /* Add some bytes to the stack.  An rtx says how many.  */
 702 extern void anti_adjust_stack (rtx);
 703
 704 /* Add some bytes to the stack while probing it.  An rtx says how many. */
 705 extern void anti_adjust_stack_and_probe (rtx, bool);
 706
 707 /* This enum is used for the following two functions.  */
 708 enum save_level {SAVE_BLOCK, SAVE_FUNCTION, SAVE_NONLOCAL};
 709
 710 /* Save the stack pointer at the specified level.  */
 711 extern void emit_stack_save (enum save_level, rtx *);
 712
 713 /* Restore the stack pointer from a save area of the specified level.  */
 714 extern void emit_stack_restore (enum save_level, rtx);
 715
 716 /* Invoke emit_stack_save for the nonlocal_goto_save_area.  */
 717 extern void update_nonlocal_goto_save_area (void);
 718
 719 /* Allocate some space on the stack dynamically and return its address.  */
 720 extern rtx allocate_dynamic_stack_space (rtx, unsigned, unsigned, bool);
 721
 722 /* Emit one stack probe at ADDRESS, an address within the stack.  */
 723 extern void emit_stack_probe (rtx);
 724
 725 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
 726    FIRST is a constant and size is a Pmode RTX.  These are offsets from
 727    the current stack pointer.  STACK_GROWS_DOWNWARD says whether to add
 728    or subtract them from the stack pointer.  */
 729 extern void probe_stack_range (HOST_WIDE_INT, rtx);
 730
 731 /* Return an rtx that refers to the value returned by a library call
 732    in its original home.  This becomes invalid if any more code is emitted.  */
 733 extern rtx hard_libcall_value (enum machine_mode, rtx);
 734
 735 extern void store_bit_field (rtx, unsigned HOST_WIDE_INT,
 736                              unsigned HOST_WIDE_INT,
 737                              unsigned HOST_WIDE_INT,
 738                              unsigned HOST_WIDE_INT,
 739                              enum machine_mode, rtx);
 740 extern rtx extract_bit_field (rtx, unsigned HOST_WIDE_INT,
 741                               unsigned HOST_WIDE_INT, int, rtx,
 742                               enum machine_mode, enum machine_mode);
 743 extern rtx extract_low_bits (enum machine_mode, enum machine_mode, rtx);
 744 extern rtx expand_mult (enum machine_mode, rtx, rtx, rtx, int);
 745 extern rtx expand_mult_highpart_adjust (enum machine_mode, rtx, rtx, rtx, rtx, int);
 746
 747 extern rtx assemble_static_space (unsigned HOST_WIDE_INT);
 748 extern int safe_from_p (const_rtx, tree, int);
 749 extern bool split_comparison (enum rtx_code, enum machine_mode,
 750                               enum rtx_code *, enum rtx_code *);
 751
 752 /* Call this once to initialize the contents of the optabs
 753    appropriately for the current target machine.  */
 754 extern void init_optabs (void);
 755 extern void init_all_optabs (struct target_optabs *);
 756
 757 /* Call this to initialize an optab function entry.  */
 758 extern rtx init_one_libfunc (const char *);
 759 extern rtx set_user_assembler_libfunc (const char *, const char *);
 760
 761 /* Build a decl for a libfunc named NAME. */
 762 extern tree build_libfunc_function (const char *);
 763
 764 /* Get the personality libfunc for a function decl.  */
 765 rtx get_personality_function (tree);
 766
 767
 768 /* In stmt.c */
 769
 770 /* Expand a GIMPLE_SWITCH statement.  */
 771 extern void expand_case (gimple);
 772
 773 /* Like expand_case but special-case for SJLJ exception dispatching.  */
 774 extern void expand_sjlj_dispatch_table (rtx, vec<tree> );
 775
 776 /* Determine whether the LEN bytes can be moved by using several move
 777    instructions.  Return nonzero if a call to move_by_pieces should
 778    succeed.  */
 779 extern int can_move_by_pieces (unsigned HOST_WIDE_INT, unsigned int);
 780
 781 extern unsigned HOST_WIDE_INT highest_pow2_factor (const_tree);
 782 bool array_at_struct_end_p (tree);
 783
 784 /* Return a tree of sizetype representing the size, in bytes, of the element
 785    of EXP, an ARRAY_REF or an ARRAY_RANGE_REF.  */
 786 extern tree array_ref_element_size (tree);
 787
 788 extern bool categorize_ctor_elements (const_tree, HOST_WIDE_INT *,
 789                                       HOST_WIDE_INT *, bool *);
 790
 791 /* Return a tree representing the offset, in bytes, of the field referenced
 792    by EXP.  This does not include any offset in DECL_FIELD_BIT_OFFSET.  */
 793 extern tree component_ref_field_offset (tree);
 794
 795 #endif /* GCC_EXPR_H */