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   /* A vector indexed by pseudo reg number.  The allocated length
 101      of this vector is regno_pointer_flag_length.  Since this
 102      vector is needed during the expansion phase when the total
 103      number of registers in the function is not yet known,
 104      it is copied and made bigger when necessary.  */
 105   char *regno_pointer_flag;
 106   int regno_pointer_flag_length;
 107
 108   /* Indexed by pseudo register number, if nonzero gives the known alignment
 109      for that pseudo (if regno_pointer_flag is set).
 110      Allocated in parallel with regno_pointer_flag.  */
 111   char *regno_pointer_align;
 112
 113   /* Indexed by pseudo register number, gives the rtx for that pseudo.
 114      Allocated in parallel with regno_pointer_flag.  */
 115   rtx *x_regno_reg_rtx;
 116 };
 117
 118 /* For backward compatibility... eventually these should all go away.  */
 119 #define reg_rtx_no (cfun->emit->x_reg_rtx_no)
 120 #define seq_rtl_expr (cfun->emit->sequence_rtl_expr)
 121 #define regno_reg_rtx (cfun->emit->x_regno_reg_rtx)
 122 #define seq_stack (cfun->emit->sequence_stack)
 123
 124 #define REGNO_POINTER_ALIGN(REGNO) (cfun->emit->regno_pointer_align[REGNO])
 125 #define REGNO_POINTER_FLAG(REGNO) (cfun->emit->regno_pointer_flag[REGNO])
 126
 127 struct expr_status
 128 {
 129   /* Number of units that we should eventually pop off the stack.
 130      These are the arguments to function calls that have already returned.  */
 131   int x_pending_stack_adjust;
 132
 133   /* Number of units that we should eventually pop off the stack.
 134      These are the arguments to function calls that have not happened yet.  */
 135   int x_arg_space_so_far;
 136
 137   /* Under some ABIs, it is the caller's responsibility to pop arguments
 138      pushed for function calls.  A naive implementation would simply pop
 139      the arguments immediately after each call.  However, if several
 140      function calls are made in a row, it is typically cheaper to pop
 141      all the arguments after all of the calls are complete since a
 142      single pop instruction can be used.  Therefore, GCC attempts to
 143      defer popping the arguments until absolutely necessary.  (For
 144      example, at the end of a conditional, the arguments must be popped,
 145      since code outside the conditional won't know whether or not the
 146      arguments need to be popped.)
 147
 148      When INHIBIT_DEFER_POP is non-zero, however, the compiler does not
 149      attempt to defer pops.  Instead, the stack is popped immediately
 150      after each call.  Rather then setting this variable directly, use
 151      NO_DEFER_POP and OK_DEFER_POP.  */
 152   int x_inhibit_defer_pop;
 153
 154   /* Nonzero means __builtin_saveregs has already been done in this function.
 155      The value is the pseudoreg containing the value __builtin_saveregs
 156      returned.  */
 157   rtx x_saveregs_value;
 158
 159   /* Similarly for __builtin_apply_args.  */
 160   rtx x_apply_args_value;
 161
 162   /* List of labels that must never be deleted.  */
 163   rtx x_forced_labels;
 164
 165   /* Postincrements that still need to be expanded.  */
 166   rtx x_pending_chain;
 167 };
 168
 169 #define pending_stack_adjust (cfun->expr->x_pending_stack_adjust)
 170 #define arg_space_so_far (cfun->expr->x_arg_space_so_far)
 171 #define inhibit_defer_pop (cfun->expr->x_inhibit_defer_pop)
 172 #define saveregs_value (cfun->expr->x_saveregs_value)
 173 #define apply_args_value (cfun->expr->x_apply_args_value)
 174 #define forced_labels (cfun->expr->x_forced_labels)
 175 #define pending_chain (cfun->expr->x_pending_chain)
 176
 177 /* This structure can save all the important global and static variables
 178    describing the status of the current function.  */
 179
 180 struct function
 181 {
 182   struct function *next_global;
 183   struct function *next;
 184
 185   struct eh_status *eh;
 186   struct stmt_status *stmt;
 187   struct expr_status *expr;
 188   struct emit_status *emit;
 189   struct varasm_status *varasm;
 190
 191   /* For function.c.  */
 192
 193   /* Name of this function.  */
 194   const char *name;
 195   /* Points to the FUNCTION_DECL of this function. */
 196   tree decl;
 197
 198   /* Number of bytes of args popped by function being compiled on its return.
 199      Zero if no bytes are to be popped.
 200      May affect compilation of return insn or of function epilogue.  */
 201   int pops_args;
 202
 203   /* Nonzero if function being compiled needs to be given an address
 204      where the value should be stored.  */
 205   int returns_struct;
 206
 207   /* Nonzero if function being compiled needs to
 208      return the address of where it has put a structure value.  */
 209   int returns_pcc_struct;
 210
 211   /* Nonzero if the current function returns a pointer type.  */
 212   int returns_pointer;
 213
 214   /* Nonzero if function being compiled needs to be passed a static chain.  */
 215   int needs_context;
 216
 217   /* Nonzero if function being compiled can call setjmp.  */
 218   int calls_setjmp;
 219
 220   /* Nonzero if function being compiled can call longjmp.  */
 221   int calls_longjmp;
 222
 223   /* Nonzero if function being compiled can call alloca,
 224      either as a subroutine or builtin.  */
 225   int calls_alloca;
 226
 227   /* Nonzero if function being compiled receives nonlocal gotos
 228      from nested functions.  */
 229
 230   int has_nonlocal_label;
 231
 232   /* Nonzero if function being compiled has nonlocal gotos to parent
 233      function.  */
 234   int has_nonlocal_goto;
 235
 236   /* Nonzero if function being compiled contains nested functions.  */
 237   int contains_functions;
 238
 239   /* Nonzero if the function being compiled issues a computed jump.  */
 240   int has_computed_jump;
 241
 242   /* Nonzero if the current function is a thunk (a lightweight function that
 243      just adjusts one of its arguments and forwards to another function), so
 244      we should try to cut corners where we can.  */
 245   int is_thunk;
 246
 247   /* If function's args have a fixed size, this is that size, in bytes.
 248      Otherwise, it is -1.
 249      May affect compilation of return insn or of function epilogue.  */
 250   int args_size;
 251
 252   /* # bytes the prologue should push and pretend that the caller pushed them.
 253      The prologue must do this, but only if parms can be passed in
 254      registers.  */
 255   int pretend_args_size;
 256
 257   /* # of bytes of outgoing arguments.  If ACCUMULATE_OUTGOING_ARGS is
 258      defined, the needed space is pushed by the prologue.  */
 259   int outgoing_args_size;
 260
 261   /* This is the offset from the arg pointer to the place where the first
 262      anonymous arg can be found, if there is one.  */
 263   rtx arg_offset_rtx;
 264
 265   /* Nonzero if current function uses varargs.h or equivalent.
 266      Zero for functions that use stdarg.h.  */
 267   int varargs;
 268
 269   /* Nonzero if current function uses stdarg.h or equivalent.
 270      Zero for functions that use varargs.h.  */
 271   int stdarg;
 272
 273   /* Quantities of various kinds of registers
 274      used for the current function's args.  */
 275   CUMULATIVE_ARGS args_info;
 276
 277   /* If non-zero, an RTL expression for the location at which the current
 278      function returns its result.  If the current function returns its
 279      result in a register, current_function_return_rtx will always be
 280      the hard register containing the result.  */
 281   rtx return_rtx;
 282
 283   /* The arg pointer hard register, or the pseudo into which it was copied.  */
 284   rtx internal_arg_pointer;
 285
 286   /* Language-specific reason why the current function cannot be made
 287      inline.  */
 288   const char *cannot_inline;
 289
 290   /* Nonzero if instrumentation calls for function entry and exit should be
 291      generated.  */
 292   int instrument_entry_exit;
 293
 294   /* Nonzero if memory access checking be enabled in the current function.  */
 295   int check_memory_usage;
 296
 297   /* Nonzero if stack limit checking should be enabled in the current
 298      function.  */
 299   int limit_stack;
 300
 301   /* Number of function calls seen so far in current function.  */
 302   int x_function_call_count;
 303
 304   /* Nonzero if this function is being processed in function-at-a-time
 305      mode.  In other words, if all tree structure for this function,
 306      including the BLOCK tree is created, before RTL generation
 307      commences.  */
 308   int x_whole_function_mode_p;
 309
 310   /* Nonzero if the back-end should not keep track of expressions that
 311      determine the size of variable-sized objects.  Normally, such
 312      expressions are saved away, and then expanded when the next
 313      function is started.  For example, if a parameter has a
 314      variable-sized type, then the size of the parameter is computed
 315      when the function body is entered.  However, some front-ends do
 316      not desire this behavior.  */
 317   int x_dont_save_pending_sizes_p;
 318
 319   /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
 320      (labels to which there can be nonlocal gotos from nested functions)
 321      in this function.  */
 322   tree x_nonlocal_labels;
 323
 324   /* List (chain of EXPR_LIST) of stack slots that hold the current handlers
 325      for nonlocal gotos.  There is one for every nonlocal label in the
 326      function; this list matches the one in nonlocal_labels.
 327      Zero when function does not have nonlocal labels.  */
 328   rtx x_nonlocal_goto_handler_slots;
 329
 330   /* List (chain of EXPR_LIST) of labels heading the current handlers for
 331      nonlocal gotos.  */
 332   rtx x_nonlocal_goto_handler_labels;
 333
 334   /* RTX for stack slot that holds the stack pointer value to restore
 335      for a nonlocal goto.
 336      Zero when function does not have nonlocal labels.  */
 337   rtx x_nonlocal_goto_stack_level;
 338
 339   /* Label that will go on parm cleanup code, if any.
 340      Jumping to this label runs cleanup code for parameters, if
 341      such code must be run.  Following this code is the logical return
 342      label.  */
 343   rtx x_cleanup_label;
 344
 345   /* Label that will go on function epilogue.
 346      Jumping to this label serves as a "return" instruction
 347      on machines which require execution of the epilogue on all returns.  */
 348   rtx x_return_label;
 349
 350   /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
 351      So we can mark them all live at the end of the function, if nonopt.  */
 352   rtx x_save_expr_regs;
 353
 354   /* List (chain of EXPR_LISTs) of all stack slots in this function.
 355      Made for the sake of unshare_all_rtl.  */
 356   rtx x_stack_slot_list;
 357
 358   /* Chain of all RTL_EXPRs that have insns in them.  */
 359   tree x_rtl_expr_chain;
 360
 361   /* Label to jump back to for tail recursion, or 0 if we have
 362      not yet needed one for this function.  */
 363   rtx x_tail_recursion_label;
 364
 365   /* Place after which to insert the tail_recursion_label if we need one.  */
 366   rtx x_tail_recursion_reentry;
 367
 368   /* Location at which to save the argument pointer if it will need to be
 369      referenced.  There are two cases where this is done: if nonlocal gotos
 370      exist, or if vars stored at an offset from the argument pointer will be
 371      needed by inner routines.  */
 372   rtx x_arg_pointer_save_area;
 373
 374   /* Offset to end of allocated area of stack frame.
 375      If stack grows down, this is the address of the last stack slot allocated.
 376      If stack grows up, this is the address for the next slot.  */
 377   HOST_WIDE_INT x_frame_offset;
 378
 379   /* List (chain of TREE_LISTs) of static chains for containing functions.
 380      Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
 381      in an RTL_EXPR in the TREE_VALUE.  */
 382   tree x_context_display;
 383
 384   /* List (chain of TREE_LISTs) of trampolines for nested functions.
 385      The trampoline sets up the static chain and jumps to the function.
 386      We supply the trampoline's address when the function's address is
 387      requested.
 388
 389      Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
 390      in an RTL_EXPR in the TREE_VALUE.  */
 391   tree x_trampoline_list;
 392
 393   /* Insn after which register parms and SAVE_EXPRs are born, if nonopt.  */
 394   rtx x_parm_birth_insn;
 395
 396   /* Last insn of those whose job was to put parms into their nominal
 397      homes.  */
 398   rtx x_last_parm_insn;
 399
 400   /* 1 + last pseudo register number possibly used for loading a copy
 401      of a parameter of this function. */
 402   int x_max_parm_reg;
 403
 404   /* Vector indexed by REGNO, containing location on stack in which
 405      to put the parm which is nominally in pseudo register REGNO,
 406      if we discover that that parm must go in the stack.  The highest
 407      element in this vector is one less than MAX_PARM_REG, above.  */
 408   rtx *x_parm_reg_stack_loc;
 409
 410   /* List of all temporaries allocated, both available and in use.  */
 411   struct temp_slot *x_temp_slots;
 412
 413   /* Current nesting level for temporaries.  */
 414   int x_temp_slot_level;
 415
 416   /* Current nesting level for variables in a block.  */
 417   int x_var_temp_slot_level;
 418
 419   /* When temporaries are created by TARGET_EXPRs, they are created at
 420      this level of temp_slot_level, so that they can remain allocated
 421      until no longer needed.  CLEANUP_POINT_EXPRs define the lifetime
 422      of TARGET_EXPRs.  */
 423   int x_target_temp_slot_level;
 424
 425   /* This slot is initialized as 0 and is added to
 426      during the nested function.  */
 427   struct var_refs_queue *fixup_var_refs_queue;
 428
 429   /* For tree.c.  */
 430   int all_types_permanent;
 431   struct momentary_level *momentary_stack;
 432   char *maybepermanent_firstobj;
 433   char *temporary_firstobj;
 434   char *momentary_firstobj;
 435   char *momentary_function_firstobj;
 436   struct obstack *current_obstack;
 437   struct obstack *function_obstack;
 438   struct obstack *function_maybepermanent_obstack;
 439   struct obstack *expression_obstack;
 440   struct obstack *saveable_obstack;
 441   struct obstack *rtl_obstack;
 442
 443   /* For integrate.c.  */
 444   int inlinable;
 445   /* This is in fact an rtvec.  */
 446   void *original_arg_vector;
 447   tree original_decl_initial;
 448   /* Last insn of those whose job was to put parms into their nominal
 449      homes.  */
 450   rtx inl_last_parm_insn;
 451   /* Highest label number in current function.  */
 452   int inl_max_label_num;
 453
 454   /* Nonzero if the current function uses the constant pool.  */
 455   int uses_const_pool;
 456
 457   /* For md files.  */
 458
 459   /* Nonzero if the current function uses pic_offset_table_rtx.  */
 460   int uses_pic_offset_table;
 461   /* tm.h can use this to store whatever it likes.  */
 462   struct machine_function *machine;
 463   /* The largest alignment of slot allocated on the stack.  */
 464   int stack_alignment_needed;
 465   /* Preferred alignment of the end of stack frame.  */
 466   int preferred_stack_boundary;
 467
 468   /* Language-specific code can use this to store whatever it likes.  */
 469   struct language_function *language;
 470
 471   /* For reorg.  */
 472
 473   /* If some insns can be deferred to the delay slots of the epilogue, the
 474      delay list for them is recorded here.  */
 475   rtx epilogue_delay_list;
 476 };
 477
 478 /* The function currently being compiled.  */
 479 extern struct function *cfun;
 480
 481 /* A list of all functions we have compiled so far.  */
 482 extern struct function *all_functions;
 483
 484 /* For backward compatibility... eventually these should all go away.  */
 485 #define current_function_name (cfun->name)
 486 #define current_function_pops_args (cfun->pops_args)
 487 #define current_function_returns_struct (cfun->returns_struct)
 488 #define current_function_returns_pcc_struct (cfun->returns_pcc_struct)
 489 #define current_function_returns_pointer (cfun->returns_pointer)
 490 #define current_function_needs_context (cfun->needs_context)
 491 #define current_function_calls_setjmp (cfun->calls_setjmp)
 492 #define current_function_calls_alloca (cfun->calls_alloca)
 493 #define current_function_calls_longjmp (cfun->calls_longjmp)
 494 #define current_function_has_computed_jump (cfun->has_computed_jump)
 495 #define current_function_contains_functions (cfun->contains_functions)
 496 #define current_function_is_thunk (cfun->is_thunk)
 497 #define current_function_args_info (cfun->args_info)
 498 #define current_function_args_size (cfun->args_size)
 499 #define current_function_pretend_args_size (cfun->pretend_args_size)
 500 #define current_function_outgoing_args_size (cfun->outgoing_args_size)
 501 #define current_function_arg_offset_rtx (cfun->arg_offset_rtx)
 502 #define current_function_varargs (cfun->varargs)
 503 #define current_function_stdarg (cfun->stdarg)
 504 #define current_function_internal_arg_pointer (cfun->internal_arg_pointer)
 505 #define current_function_return_rtx (cfun->return_rtx)
 506 #define current_function_instrument_entry_exit (cfun->instrument_entry_exit)
 507 #define current_function_check_memory_usage (cfun->check_memory_usage)
 508 #define current_function_limit_stack (cfun->limit_stack)
 509 #define current_function_uses_pic_offset_table (cfun->uses_pic_offset_table)
 510 #define current_function_uses_const_pool (cfun->uses_const_pool)
 511 #define current_function_cannot_inline (cfun->cannot_inline)
 512 #define current_function_epilogue_delay_list (cfun->epilogue_delay_list)
 513 #define current_function_has_nonlocal_label (cfun->has_nonlocal_label)
 514 #define current_function_has_nonlocal_goto (cfun->has_nonlocal_goto)
 515
 516 #define max_parm_reg (cfun->x_max_parm_reg)
 517 #define parm_reg_stack_loc (cfun->x_parm_reg_stack_loc)
 518 #define cleanup_label (cfun->x_cleanup_label)
 519 #define return_label (cfun->x_return_label)
 520 #define save_expr_regs (cfun->x_save_expr_regs)
 521 #define stack_slot_list (cfun->x_stack_slot_list)
 522 #define parm_birth_insn (cfun->x_parm_birth_insn)
 523 #define frame_offset (cfun->x_frame_offset)
 524 #define tail_recursion_label (cfun->x_tail_recursion_label)
 525 #define tail_recursion_reentry (cfun->x_tail_recursion_reentry)
 526 #define arg_pointer_save_area (cfun->x_arg_pointer_save_area)
 527 #define rtl_expr_chain (cfun->x_rtl_expr_chain)
 528 #define last_parm_insn (cfun->x_last_parm_insn)
 529 #define context_display (cfun->x_context_display)
 530 #define trampoline_list (cfun->x_trampoline_list)
 531 #define function_call_count (cfun->x_function_call_count)
 532 #define temp_slots (cfun->x_temp_slots)
 533 #define temp_slot_level (cfun->x_temp_slot_level)
 534 #define target_temp_slot_level (cfun->x_target_temp_slot_level)
 535 #define var_temp_slot_level (cfun->x_var_temp_slot_level)
 536 #define nonlocal_labels (cfun->x_nonlocal_labels)
 537 #define nonlocal_goto_handler_slots (cfun->x_nonlocal_goto_handler_slots)
 538 #define nonlocal_goto_handler_labels (cfun->x_nonlocal_goto_handler_labels)
 539 #define nonlocal_goto_stack_level (cfun->x_nonlocal_goto_stack_level)
 540
 541 /* The FUNCTION_DECL for an inline function currently being expanded.  */
 542 extern tree inline_function_decl;
 543
 544 /* Given a function decl for a containing function,
 545    return the `struct function' for it.  */
 546 struct function *find_function_data PARAMS ((tree));
 547
 548 /* Pointer to chain of `struct function' for containing functions.  */
 549 extern struct function *outer_function_chain;
 550
 551 /* Put all this function's BLOCK nodes into a vector and return it.
 552    Also store in each NOTE for the beginning or end of a block
 553    the index of that block in the vector.  */
 554 extern void identify_blocks PARAMS ((tree, rtx));
 555
 556 /* Set BLOCK_NUMBER for all the blocks in FN.  */
 557 extern void number_blocks PARAMS ((tree));
 558
 559 /* Return size needed for stack frame based on slots so far allocated.
 560    This size counts from zero.  It is not rounded to STACK_BOUNDARY;
 561    the caller may have to do that.  */
 562 extern HOST_WIDE_INT get_frame_size     PARAMS ((void));
 563 /* Likewise, but for a different than the current function.  */
 564 extern HOST_WIDE_INT get_func_frame_size        PARAMS ((struct function *));
 565
 566 /* These variables hold pointers to functions to
 567    save and restore machine-specific data,
 568    in push_function_context and pop_function_context.  */
 569 extern void (*init_machine_status)      PARAMS ((struct function *));
 570 extern void (*mark_machine_status)      PARAMS ((struct function *));
 571 extern void (*save_machine_status)      PARAMS ((struct function *));
 572 extern void (*restore_machine_status)   PARAMS ((struct function *));
 573 extern void (*free_machine_status)      PARAMS ((struct function *));
 574
 575 /* Likewise, but for language-specific data.  */
 576 extern void (*init_lang_status)         PARAMS ((struct function *));
 577 extern void (*mark_lang_status)         PARAMS ((struct function *));
 578 extern void (*save_lang_status)         PARAMS ((struct function *));
 579 extern void (*restore_lang_status)      PARAMS ((struct function *));
 580 extern void (*free_lang_status)         PARAMS ((struct function *));
 581
 582 /* Save and restore status information for a nested function.  */
 583 extern void save_tree_status            PARAMS ((struct function *));
 584 extern void restore_tree_status         PARAMS ((struct function *));
 585 extern void restore_emit_status         PARAMS ((struct function *));
 586 extern void free_after_parsing          PARAMS ((struct function *));
 587 extern void free_after_compilation      PARAMS ((struct function *));
 588
 589 extern void init_varasm_status          PARAMS ((struct function *));
 590 extern void free_varasm_status          PARAMS ((struct function *));
 591 extern void free_emit_status            PARAMS ((struct function *));
 592 extern void free_stmt_status            PARAMS ((struct function *));
 593 extern void free_eh_status              PARAMS ((struct function *));
 594 extern void free_expr_status            PARAMS ((struct function *));
 595
 596 extern rtx get_first_block_beg          PARAMS ((void));
 597
 598 #ifdef RTX_CODE
 599 extern void diddle_return_value         PARAMS ((void (*)(rtx, void*), void*));
 600 extern void clobber_return_register     PARAMS ((void));
 601 extern void use_return_register         PARAMS ((void));
 602 #endif
 603
 604 extern void init_virtual_regs           PARAMS ((struct emit_status *));
 605
 606 /* Called once, at initialization, to initialize function.c.  */
 607 extern void init_function_once          PARAMS ((void));
 608
 609 #ifdef rtx
 610 #undef rtx
 611 #endif
 612
 613 #ifdef tree
 614 #undef tree
 615 #endif