gcc/function.h

   1 /* Structure for saving state for a nested function.
   2    Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   3    1999, 2000 Free Software Foundation, Inc.
   4
   5 This file is part of GNU CC.
   6
   7 GNU CC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU CC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU CC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22
  23 #if !defined(NULL_TREE) && !defined(tree)
  24 typedef union union_node *_function_tree;
  25 #define tree _function_tree
  26 #endif
  27 #if !defined(NULL_RTX) && !defined(rtx)
  28 typedef struct rtx_def *_function_rtx;
  29 #define rtx _function_rtx
  30 #endif
  31
  32 struct var_refs_queue
  33 {
  34   rtx modified;
  35   enum machine_mode promoted_mode;
  36   int unsignedp;
  37   struct var_refs_queue *next;
  38 };
  39
  40 /* Stack of pending (incomplete) sequences saved by `start_sequence'.
  41    Each element describes one pending sequence.
  42    The main insn-chain is saved in the last element of the chain,
  43    unless the chain is empty.  */
  44
  45 struct sequence_stack
  46 {
  47   /* First and last insns in the chain of the saved sequence.  */
  48   rtx first, last;
  49   tree sequence_rtl_expr;
  50   struct sequence_stack *next;
  51 };
  52
  53 extern struct sequence_stack *sequence_stack;
  54
  55 /* Stack of single obstacks.  */
  56
  57 struct simple_obstack_stack
  58 {
  59   struct obstack *obstack;
  60   struct simple_obstack_stack *next;
  61 };
  62 \f
  63 struct emit_status
  64 {
  65   /* This is reset to LAST_VIRTUAL_REGISTER + 1 at the start of each function.
  66      After rtl generation, it is 1 plus the largest register number used.  */
  67   int x_reg_rtx_no;
  68
  69   /* Lowest label number in current function.  */
  70   int x_first_label_num;
  71
  72   /* The ends of the doubly-linked chain of rtl for the current function.
  73      Both are reset to null at the start of rtl generation for the function.
  74
  75      start_sequence saves both of these on `sequence_stack' along with
  76      `sequence_rtl_expr' and then starts a new, nested sequence of insns.  */
  77   rtx x_first_insn;
  78   rtx x_last_insn;
  79
  80   /* RTL_EXPR within which the current sequence will be placed.  Use to
  81      prevent reuse of any temporaries within the sequence until after the
  82      RTL_EXPR is emitted.  */
  83   tree sequence_rtl_expr;
  84
  85   /* Stack of pending (incomplete) sequences saved by `start_sequence'.
  86      Each element describes one pending sequence.
  87      The main insn-chain is saved in the last element of the chain,
  88      unless the chain is empty.  */
  89   struct sequence_stack *sequence_stack;
  90
  91   /* INSN_UID for next insn emitted.
  92      Reset to 1 for each function compiled.  */
  93   int x_cur_insn_uid;
  94
  95   /* Line number and source file of the last line-number NOTE emitted.
  96      This is used to avoid generating duplicates.  */
  97   int x_last_linenum;
  98   const char *x_last_filename;
  99
 100   /* The length of the regno_pointer_align and x_regno_reg_rtx vectors.
 101      Since these vectors are needed during the expansion phase when
 102      the total number of registers in the function is not yet known,
 103      the vectors are copied and made bigger when necessary.  */
 104   int regno_pointer_align_length;
 105
 106   /* Indexed by pseudo register number, if nonzero gives the known alignment
 107      for that pseudo (if REG_POINTER is set in x_regno_reg_rtx).
 108      Allocated in parallel with x_regno_reg_rtx.  */
 109   unsigned char *regno_pointer_align;
 110
 111   /* Indexed by pseudo register number, gives the rtx for that pseudo.
 112      Allocated in parallel with regno_pointer_align.  */
 113   rtx *x_regno_reg_rtx;
 114 };
 115
 116 /* For backward compatibility... eventually these should all go away.  */
 117 #define reg_rtx_no (cfun->emit->x_reg_rtx_no)
 118 #define seq_rtl_expr (cfun->emit->sequence_rtl_expr)
 119 #define regno_reg_rtx (cfun->emit->x_regno_reg_rtx)
 120 #define seq_stack (cfun->emit->sequence_stack)
 121
 122 #define REGNO_POINTER_ALIGN(REGNO) (cfun->emit->regno_pointer_align[REGNO])
 123
 124 struct expr_status
 125 {
 126   /* Number of units that we should eventually pop off the stack.
 127      These are the arguments to function calls that have already returned.  */
 128   int x_pending_stack_adjust;
 129
 130   /* Under some ABIs, it is the caller's responsibility to pop arguments
 131      pushed for function calls.  A naive implementation would simply pop
 132      the arguments immediately after each call.  However, if several
 133      function calls are made in a row, it is typically cheaper to pop
 134      all the arguments after all of the calls are complete since a
 135      single pop instruction can be used.  Therefore, GCC attempts to
 136      defer popping the arguments until absolutely necessary.  (For
 137      example, at the end of a conditional, the arguments must be popped,
 138      since code outside the conditional won't know whether or not the
 139      arguments need to be popped.)
 140
 141      When INHIBIT_DEFER_POP is non-zero, however, the compiler does not
 142      attempt to defer pops.  Instead, the stack is popped immediately
 143      after each call.  Rather then setting this variable directly, use
 144      NO_DEFER_POP and OK_DEFER_POP.  */
 145   int x_inhibit_defer_pop;
 146
 147   /* If PREFERRED_STACK_BOUNDARY and PUSH_ROUNDING are defined, the stack
 148      boundary can be momentairly unaligned while pushing the arguments.
 149      Record the delta since last aligned boundary here in order to get
 150      stack alignment in the nested function calls working right.  */
 151   int x_stack_pointer_delta;
 152
 153   /* Nonzero means __builtin_saveregs has already been done in this function.
 154      The value is the pseudoreg containing the value __builtin_saveregs
 155      returned.  */
 156   rtx x_saveregs_value;
 157
 158   /* Similarly for __builtin_apply_args.  */
 159   rtx x_apply_args_value;
 160
 161   /* List of labels that must never be deleted.  */
 162   rtx x_forced_labels;
 163
 164   /* Postincrements that still need to be expanded.  */
 165   rtx x_pending_chain;
 166 };
 167
 168 #define pending_stack_adjust (cfun->expr->x_pending_stack_adjust)
 169 #define inhibit_defer_pop (cfun->expr->x_inhibit_defer_pop)
 170 #define saveregs_value (cfun->expr->x_saveregs_value)
 171 #define apply_args_value (cfun->expr->x_apply_args_value)
 172 #define forced_labels (cfun->expr->x_forced_labels)
 173 #define pending_chain (cfun->expr->x_pending_chain)
 174 #define stack_pointer_delta (cfun->expr->x_stack_pointer_delta)
 175
 176 /* This structure can save all the important global and static variables
 177    describing the status of the current function.  */
 178
 179 struct function
 180 {
 181   struct function *next_global;
 182   struct function *next;
 183
 184   struct eh_status *eh;
 185   struct stmt_status *stmt;
 186   struct expr_status *expr;
 187   struct emit_status *emit;
 188   struct varasm_status *varasm;
 189
 190   /* For function.c.  */
 191
 192   /* Name of this function.  */
 193   const char *name;
 194   /* Points to the FUNCTION_DECL of this function. */
 195   tree decl;
 196
 197   /* Number of bytes of args popped by function being compiled on its return.
 198      Zero if no bytes are to be popped.
 199      May affect compilation of return insn or of function epilogue.  */
 200   int pops_args;
 201
 202   /* Nonzero if function being compiled needs to be given an address
 203      where the value should be stored.  */
 204   int returns_struct;
 205
 206   /* Nonzero if function being compiled needs to
 207      return the address of where it has put a structure value.  */
 208   int returns_pcc_struct;
 209
 210   /* Nonzero if the current function returns a pointer type.  */
 211   int returns_pointer;
 212
 213   /* Nonzero if function being compiled needs to be passed a static chain.  */
 214   int needs_context;
 215
 216   /* Nonzero if function being compiled can call setjmp.  */
 217   int calls_setjmp;
 218
 219   /* Nonzero if function being compiled can call longjmp.  */
 220   int calls_longjmp;
 221
 222   /* Nonzero if function being compiled can call alloca,
 223      either as a subroutine or builtin.  */
 224   int calls_alloca;
 225
 226   /* Nonzero if function being compiled receives nonlocal gotos
 227      from nested functions.  */
 228
 229   int has_nonlocal_label;
 230
 231   /* Nonzero if function being compiled has nonlocal gotos to parent
 232      function.  */
 233   int has_nonlocal_goto;
 234
 235   /* Nonzero if function being compiled contains nested functions.  */
 236   int contains_functions;
 237
 238   /* Nonzero if the function being compiled issues a computed jump.  */
 239   int has_computed_jump;
 240
 241   /* Nonzero if the current function is a thunk (a lightweight function that
 242      just adjusts one of its arguments and forwards to another function), so
 243      we should try to cut corners where we can.  */
 244   int is_thunk;
 245
 246   /* If function's args have a fixed size, this is that size, in bytes.
 247      Otherwise, it is -1.
 248      May affect compilation of return insn or of function epilogue.  */
 249   int args_size;
 250
 251   /* # bytes the prologue should push and pretend that the caller pushed them.
 252      The prologue must do this, but only if parms can be passed in
 253      registers.  */
 254   int pretend_args_size;
 255
 256   /* # of bytes of outgoing arguments.  If ACCUMULATE_OUTGOING_ARGS is
 257      defined, the needed space is pushed by the prologue.  */
 258   int outgoing_args_size;
 259
 260   /* This is the offset from the arg pointer to the place where the first
 261      anonymous arg can be found, if there is one.  */
 262   rtx arg_offset_rtx;
 263
 264   /* Nonzero if current function uses varargs.h or equivalent.
 265      Zero for functions that use stdarg.h.  */
 266   int varargs;
 267
 268   /* Nonzero if current function uses stdarg.h or equivalent.
 269      Zero for functions that use varargs.h.  */
 270   int stdarg;
 271
 272   /* Quantities of various kinds of registers
 273      used for the current function's args.  */
 274   CUMULATIVE_ARGS args_info;
 275
 276   /* If non-zero, an RTL expression for the location at which the current
 277      function returns its result.  If the current function returns its
 278      result in a register, current_function_return_rtx will always be
 279      the hard register containing the result.  */
 280   rtx return_rtx;
 281
 282   /* The arg pointer hard register, or the pseudo into which it was copied.  */
 283   rtx internal_arg_pointer;
 284
 285   /* Language-specific reason why the current function cannot be made
 286      inline.  */
 287   const char *cannot_inline;
 288
 289   /* Nonzero if instrumentation calls for function entry and exit should be
 290      generated.  */
 291   int instrument_entry_exit;
 292
 293   /* Nonzero if memory access checking be enabled in the current function.  */
 294   int check_memory_usage;
 295
 296   /* Nonzero if stack limit checking should be enabled in the current
 297      function.  */
 298   int limit_stack;
 299
 300   /* Number of function calls seen so far in current function.  */
 301   int x_function_call_count;
 302
 303   /* Nonzero if this function is being processed in function-at-a-time
 304      mode.  In other words, if all tree structure for this function,
 305      including the BLOCK tree, is created before RTL generation
 306      commences.  */
 307   int x_whole_function_mode_p;
 308
 309   /* Nonzero if the back-end should not keep track of expressions that
 310      determine the size of variable-sized objects.  Normally, such
 311      expressions are saved away, and then expanded when the next
 312      function is started.  For example, if a parameter has a
 313      variable-sized type, then the size of the parameter is computed
 314      when the function body is entered.  However, some front-ends do
 315      not desire this behavior.  */
 316   int x_dont_save_pending_sizes_p;
 317
 318   /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
 319      (labels to which there can be nonlocal gotos from nested functions)
 320      in this function.  */
 321   tree x_nonlocal_labels;
 322
 323   /* List (chain of EXPR_LIST) of stack slots that hold the current handlers
 324      for nonlocal gotos.  There is one for every nonlocal label in the
 325      function; this list matches the one in nonlocal_labels.
 326      Zero when function does not have nonlocal labels.  */
 327   rtx x_nonlocal_goto_handler_slots;
 328
 329   /* List (chain of EXPR_LIST) of labels heading the current handlers for
 330      nonlocal gotos.  */
 331   rtx x_nonlocal_goto_handler_labels;
 332
 333   /* RTX for stack slot that holds the stack pointer value to restore
 334      for a nonlocal goto.
 335      Zero when function does not have nonlocal labels.  */
 336   rtx x_nonlocal_goto_stack_level;
 337
 338   /* Label that will go on parm cleanup code, if any.
 339      Jumping to this label runs cleanup code for parameters, if
 340      such code must be run.  Following this code is the logical return
 341      label.  */
 342   rtx x_cleanup_label;
 343
 344   /* Label that will go on function epilogue.
 345      Jumping to this label serves as a "return" instruction
 346      on machines which require execution of the epilogue on all returns.  */
 347   rtx x_return_label;
 348
 349   /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
 350      So we can mark them all live at the end of the function, if nonopt.  */
 351   rtx x_save_expr_regs;
 352
 353   /* List (chain of EXPR_LISTs) of all stack slots in this function.
 354      Made for the sake of unshare_all_rtl.  */
 355   rtx x_stack_slot_list;
 356
 357   /* Chain of all RTL_EXPRs that have insns in them.  */
 358   tree x_rtl_expr_chain;
 359
 360   /* Label to jump back to for tail recursion, or 0 if we have
 361      not yet needed one for this function.  */
 362   rtx x_tail_recursion_label;
 363
 364   /* Place after which to insert the tail_recursion_label if we need one.  */
 365   rtx x_tail_recursion_reentry;
 366
 367   /* Location at which to save the argument pointer if it will need to be
 368      referenced.  There are two cases where this is done: if nonlocal gotos
 369      exist, or if vars stored at an offset from the argument pointer will be
 370      needed by inner routines.  */
 371   rtx x_arg_pointer_save_area;
 372
 373   /* If the function returns non-void, we will emit a clobber of the
 374      return registers just in case the user fell off the end without
 375      returning a proper value.  This is that insn.  */
 376   rtx x_clobber_return_insn;
 377
 378   /* Offset to end of allocated area of stack frame.
 379      If stack grows down, this is the address of the last stack slot allocated.
 380      If stack grows up, this is the address for the next slot.  */
 381   HOST_WIDE_INT x_frame_offset;
 382
 383   /* List (chain of TREE_LISTs) of static chains for containing functions.
 384      Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
 385      in an RTL_EXPR in the TREE_VALUE.  */
 386   tree x_context_display;
 387
 388   /* List (chain of TREE_LISTs) of trampolines for nested functions.
 389      The trampoline sets up the static chain and jumps to the function.
 390      We supply the trampoline's address when the function's address is
 391      requested.
 392
 393      Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
 394      in an RTL_EXPR in the TREE_VALUE.  */
 395   tree x_trampoline_list;
 396
 397   /* Insn after which register parms and SAVE_EXPRs are born, if nonopt.  */
 398   rtx x_parm_birth_insn;
 399
 400   /* Last insn of those whose job was to put parms into their nominal
 401      homes.  */
 402   rtx x_last_parm_insn;
 403
 404   /* 1 + last pseudo register number possibly used for loading a copy
 405      of a parameter of this function. */
 406   unsigned int x_max_parm_reg;
 407
 408   /* Vector indexed by REGNO, containing location on stack in which
 409      to put the parm which is nominally in pseudo register REGNO,
 410      if we discover that that parm must go in the stack.  The highest
 411      element in this vector is one less than MAX_PARM_REG, above.  */
 412   rtx *x_parm_reg_stack_loc;
 413
 414   /* List of all temporaries allocated, both available and in use.  */
 415   struct temp_slot *x_temp_slots;
 416
 417   /* Current nesting level for temporaries.  */
 418   int x_temp_slot_level;
 419
 420   /* Current nesting level for variables in a block.  */
 421   int x_var_temp_slot_level;
 422
 423   /* When temporaries are created by TARGET_EXPRs, they are created at
 424      this level of temp_slot_level, so that they can remain allocated
 425      until no longer needed.  CLEANUP_POINT_EXPRs define the lifetime
 426      of TARGET_EXPRs.  */
 427   int x_target_temp_slot_level;
 428
 429   /* This slot is initialized as 0 and is added to
 430      during the nested function.  */
 431   struct var_refs_queue *fixup_var_refs_queue;
 432
 433   /* For integrate.c.  */
 434   int inlinable;
 435   int no_debugging_symbols;
 436   /* This is in fact an rtvec.  */
 437   void *original_arg_vector;
 438   tree original_decl_initial;
 439   /* Last insn of those whose job was to put parms into their nominal
 440      homes.  */
 441   rtx inl_last_parm_insn;
 442   /* Highest label number in current function.  */
 443   int inl_max_label_num;
 444
 445   /* Nonzero if the current function uses the constant pool.  */
 446   int uses_const_pool;
 447
 448   /* For md files.  */
 449
 450   /* Nonzero if the current function uses pic_offset_table_rtx.  */
 451   int uses_pic_offset_table;
 452   /* tm.h can use this to store whatever it likes.  */
 453   struct machine_function *machine;
 454   /* The largest alignment of slot allocated on the stack.  */
 455   int stack_alignment_needed;
 456   /* Preferred alignment of the end of stack frame.  */
 457   int preferred_stack_boundary;
 458
 459   /* Language-specific code can use this to store whatever it likes.  */
 460   struct language_function *language;
 461
 462   /* For reorg.  */
 463
 464   /* If some insns can be deferred to the delay slots of the epilogue, the
 465      delay list for them is recorded here.  */
 466   rtx epilogue_delay_list;
 467 };
 468
 469 /* The function currently being compiled.  */
 470 extern struct function *cfun;
 471
 472 /* A list of all functions we have compiled so far.  */
 473 extern struct function *all_functions;
 474
 475 /* For backward compatibility... eventually these should all go away.  */
 476 #define current_function_name (cfun->name)
 477 #define current_function_pops_args (cfun->pops_args)
 478 #define current_function_returns_struct (cfun->returns_struct)
 479 #define current_function_returns_pcc_struct (cfun->returns_pcc_struct)
 480 #define current_function_returns_pointer (cfun->returns_pointer)
 481 #define current_function_needs_context (cfun->needs_context)
 482 #define current_function_calls_setjmp (cfun->calls_setjmp)
 483 #define current_function_calls_alloca (cfun->calls_alloca)
 484 #define current_function_calls_longjmp (cfun->calls_longjmp)
 485 #define current_function_has_computed_jump (cfun->has_computed_jump)
 486 #define current_function_contains_functions (cfun->contains_functions)
 487 #define current_function_is_thunk (cfun->is_thunk)
 488 #define current_function_args_info (cfun->args_info)
 489 #define current_function_args_size (cfun->args_size)
 490 #define current_function_pretend_args_size (cfun->pretend_args_size)
 491 #define current_function_outgoing_args_size (cfun->outgoing_args_size)
 492 #define current_function_arg_offset_rtx (cfun->arg_offset_rtx)
 493 #define current_function_varargs (cfun->varargs)
 494 #define current_function_stdarg (cfun->stdarg)
 495 #define current_function_internal_arg_pointer (cfun->internal_arg_pointer)
 496 #define current_function_return_rtx (cfun->return_rtx)
 497 #define current_function_instrument_entry_exit (cfun->instrument_entry_exit)
 498 #define current_function_check_memory_usage (cfun->check_memory_usage)
 499 #define current_function_limit_stack (cfun->limit_stack)
 500 #define current_function_uses_pic_offset_table (cfun->uses_pic_offset_table)
 501 #define current_function_uses_const_pool (cfun->uses_const_pool)
 502 #define current_function_cannot_inline (cfun->cannot_inline)
 503 #define current_function_epilogue_delay_list (cfun->epilogue_delay_list)
 504 #define current_function_has_nonlocal_label (cfun->has_nonlocal_label)
 505 #define current_function_has_nonlocal_goto (cfun->has_nonlocal_goto)
 506
 507 #define max_parm_reg (cfun->x_max_parm_reg)
 508 #define parm_reg_stack_loc (cfun->x_parm_reg_stack_loc)
 509 #define cleanup_label (cfun->x_cleanup_label)
 510 #define return_label (cfun->x_return_label)
 511 #define save_expr_regs (cfun->x_save_expr_regs)
 512 #define stack_slot_list (cfun->x_stack_slot_list)
 513 #define parm_birth_insn (cfun->x_parm_birth_insn)
 514 #define frame_offset (cfun->x_frame_offset)
 515 #define tail_recursion_label (cfun->x_tail_recursion_label)
 516 #define tail_recursion_reentry (cfun->x_tail_recursion_reentry)
 517 #define arg_pointer_save_area (cfun->x_arg_pointer_save_area)
 518 #define rtl_expr_chain (cfun->x_rtl_expr_chain)
 519 #define last_parm_insn (cfun->x_last_parm_insn)
 520 #define context_display (cfun->x_context_display)
 521 #define trampoline_list (cfun->x_trampoline_list)
 522 #define function_call_count (cfun->x_function_call_count)
 523 #define temp_slots (cfun->x_temp_slots)
 524 #define temp_slot_level (cfun->x_temp_slot_level)
 525 #define target_temp_slot_level (cfun->x_target_temp_slot_level)
 526 #define var_temp_slot_level (cfun->x_var_temp_slot_level)
 527 #define nonlocal_labels (cfun->x_nonlocal_labels)
 528 #define nonlocal_goto_handler_slots (cfun->x_nonlocal_goto_handler_slots)
 529 #define nonlocal_goto_handler_labels (cfun->x_nonlocal_goto_handler_labels)
 530 #define nonlocal_goto_stack_level (cfun->x_nonlocal_goto_stack_level)
 531
 532 /* The FUNCTION_DECL for an inline function currently being expanded.  */
 533 extern tree inline_function_decl;
 534
 535 /* Given a function decl for a containing function,
 536    return the `struct function' for it.  */
 537 struct function *find_function_data PARAMS ((tree));
 538
 539 /* Pointer to chain of `struct function' for containing functions.  */
 540 extern struct function *outer_function_chain;
 541
 542 /* Set NOTE_BLOCK for each block note in the current function.  */
 543 extern void identify_blocks PARAMS ((void));
 544
 545 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
 546    and create duplicate blocks.  */
 547 extern void reorder_blocks PARAMS ((void));
 548
 549 /* Set BLOCK_NUMBER for all the blocks in FN.  */
 550 extern void number_blocks PARAMS ((tree));
 551
 552 /* Return size needed for stack frame based on slots so far allocated.
 553    This size counts from zero.  It is not rounded to STACK_BOUNDARY;
 554    the caller may have to do that.  */
 555 extern HOST_WIDE_INT get_frame_size     PARAMS ((void));
 556 /* Likewise, but for a different than the current function.  */
 557 extern HOST_WIDE_INT get_func_frame_size        PARAMS ((struct function *));
 558
 559 /* These variables hold pointers to functions to
 560    save and restore machine-specific data,
 561    in push_function_context and pop_function_context.  */
 562 extern void (*init_machine_status)      PARAMS ((struct function *));
 563 extern void (*mark_machine_status)      PARAMS ((struct function *));
 564 extern void (*save_machine_status)      PARAMS ((struct function *));
 565 extern void (*restore_machine_status)   PARAMS ((struct function *));
 566 extern void (*free_machine_status)      PARAMS ((struct function *));
 567
 568 /* Likewise, but for language-specific data.  */
 569 extern void (*init_lang_status)         PARAMS ((struct function *));
 570 extern void (*mark_lang_status)         PARAMS ((struct function *));
 571 extern void (*save_lang_status)         PARAMS ((struct function *));
 572 extern void (*restore_lang_status)      PARAMS ((struct function *));
 573 extern void (*free_lang_status)         PARAMS ((struct function *));
 574
 575 /* Save and restore status information for a nested function.  */
 576 extern void restore_emit_status         PARAMS ((struct function *));
 577 extern void free_after_parsing          PARAMS ((struct function *));
 578 extern void free_after_compilation      PARAMS ((struct function *));
 579
 580 extern void init_varasm_status          PARAMS ((struct function *));
 581 extern void free_varasm_status          PARAMS ((struct function *));
 582 extern void free_emit_status            PARAMS ((struct function *));
 583 extern void free_stmt_status            PARAMS ((struct function *));
 584 extern void free_eh_status              PARAMS ((struct function *));
 585 extern void free_expr_status            PARAMS ((struct function *));
 586
 587 extern rtx get_first_block_beg          PARAMS ((void));
 588
 589 #ifdef RTX_CODE
 590 extern void diddle_return_value         PARAMS ((void (*)(rtx, void*), void*));
 591 extern void clobber_return_register     PARAMS ((void));
 592 extern void use_return_register         PARAMS ((void));
 593 #endif
 594
 595 extern void init_virtual_regs           PARAMS ((struct emit_status *));
 596
 597 /* Called once, at initialization, to initialize function.c.  */
 598 extern void init_function_once          PARAMS ((void));
 599
 600 #ifdef rtx
 601 #undef rtx
 602 #endif
 603
 604 #ifdef tree
 605 #undef tree
 606 #endif