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 GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22 struct var_refs_queue
  23 {
  24   rtx modified;
  25   enum machine_mode promoted_mode;
  26   int unsignedp;
  27   struct var_refs_queue *next;
  28 };
  29
  30 /* Stack of pending (incomplete) sequences saved by `start_sequence'.
  31    Each element describes one pending sequence.
  32    The main insn-chain is saved in the last element of the chain,
  33    unless the chain is empty.  */
  34
  35 struct sequence_stack
  36 {
  37   /* First and last insns in the chain of the saved sequence.  */
  38   rtx first, last;
  39   tree sequence_rtl_expr;
  40   struct sequence_stack *next;
  41 };
  42
  43 extern struct sequence_stack *sequence_stack;
  44
  45 /* Stack of single obstacks.  */
  46
  47 struct simple_obstack_stack
  48 {
  49   struct obstack *obstack;
  50   struct simple_obstack_stack *next;
  51 };
  52 \f
  53 struct emit_status
  54 {
  55   /* This is reset to LAST_VIRTUAL_REGISTER + 1 at the start of each function.
  56      After rtl generation, it is 1 plus the largest register number used.  */
  57   int x_reg_rtx_no;
  58
  59   /* Lowest label number in current function.  */
  60   int x_first_label_num;
  61
  62   /* The ends of the doubly-linked chain of rtl for the current function.
  63      Both are reset to null at the start of rtl generation for the function.
  64
  65      start_sequence saves both of these on `sequence_stack' along with
  66      `sequence_rtl_expr' and then starts a new, nested sequence of insns.  */
  67   rtx x_first_insn;
  68   rtx x_last_insn;
  69
  70   /* RTL_EXPR within which the current sequence will be placed.  Use to
  71      prevent reuse of any temporaries within the sequence until after the
  72      RTL_EXPR is emitted.  */
  73   tree sequence_rtl_expr;
  74
  75   /* Stack of pending (incomplete) sequences saved by `start_sequence'.
  76      Each element describes one pending sequence.
  77      The main insn-chain is saved in the last element of the chain,
  78      unless the chain is empty.  */
  79   struct sequence_stack *sequence_stack;
  80
  81   /* INSN_UID for next insn emitted.
  82      Reset to 1 for each function compiled.  */
  83   int x_cur_insn_uid;
  84
  85   /* Line number and source file of the last line-number NOTE emitted.
  86      This is used to avoid generating duplicates.  */
  87   int x_last_linenum;
  88   const char *x_last_filename;
  89
  90   /* The length of the regno_pointer_align, regno_decl, and x_regno_reg_rtx
  91      vectors.  Since these vectors are needed during the expansion phase when
  92      the total number of registers in the function is not yet known, the
  93      vectors are copied and made bigger when necessary.  */
  94   int regno_pointer_align_length;
  95
  96   /* Indexed by pseudo register number, if nonzero gives the known alignment
  97      for that pseudo (if REG_POINTER is set in x_regno_reg_rtx).
  98      Allocated in parallel with x_regno_reg_rtx.  */
  99   unsigned char *regno_pointer_align;
 100
 101   /* Indexed by pseudo register number, if nonzero gives the decl
 102      corresponding to that register.  */
 103   tree *regno_decl;
 104
 105   /* Indexed by pseudo register number, gives the rtx for that pseudo.
 106      Allocated in parallel with regno_pointer_align.  */
 107   rtx *x_regno_reg_rtx;
 108 };
 109
 110 /* For backward compatibility... eventually these should all go away.  */
 111 #define reg_rtx_no (cfun->emit->x_reg_rtx_no)
 112 #define seq_rtl_expr (cfun->emit->sequence_rtl_expr)
 113 #define regno_reg_rtx (cfun->emit->x_regno_reg_rtx)
 114 #define seq_stack (cfun->emit->sequence_stack)
 115
 116 #define REGNO_POINTER_ALIGN(REGNO) (cfun->emit->regno_pointer_align[REGNO])
 117 #define REGNO_DECL(REGNO) (cfun->emit->regno_decl[REGNO])
 118
 119 struct expr_status
 120 {
 121   /* Number of units that we should eventually pop off the stack.
 122      These are the arguments to function calls that have already returned.  */
 123   int x_pending_stack_adjust;
 124
 125   /* Under some ABIs, it is the caller's responsibility to pop arguments
 126      pushed for function calls.  A naive implementation would simply pop
 127      the arguments immediately after each call.  However, if several
 128      function calls are made in a row, it is typically cheaper to pop
 129      all the arguments after all of the calls are complete since a
 130      single pop instruction can be used.  Therefore, GCC attempts to
 131      defer popping the arguments until absolutely necessary.  (For
 132      example, at the end of a conditional, the arguments must be popped,
 133      since code outside the conditional won't know whether or not the
 134      arguments need to be popped.)
 135
 136      When INHIBIT_DEFER_POP is non-zero, however, the compiler does not
 137      attempt to defer pops.  Instead, the stack is popped immediately
 138      after each call.  Rather then setting this variable directly, use
 139      NO_DEFER_POP and OK_DEFER_POP.  */
 140   int x_inhibit_defer_pop;
 141
 142   /* If PREFERRED_STACK_BOUNDARY and PUSH_ROUNDING are defined, the stack
 143      boundary can be momentairly unaligned while pushing the arguments.
 144      Record the delta since last aligned boundary here in order to get
 145      stack alignment in the nested function calls working right.  */
 146   int x_stack_pointer_delta;
 147
 148   /* Nonzero means __builtin_saveregs has already been done in this function.
 149      The value is the pseudoreg containing the value __builtin_saveregs
 150      returned.  */
 151   rtx x_saveregs_value;
 152
 153   /* Similarly for __builtin_apply_args.  */
 154   rtx x_apply_args_value;
 155
 156   /* List of labels that must never be deleted.  */
 157   rtx x_forced_labels;
 158
 159   /* Postincrements that still need to be expanded.  */
 160   rtx x_pending_chain;
 161 };
 162
 163 #define pending_stack_adjust (cfun->expr->x_pending_stack_adjust)
 164 #define inhibit_defer_pop (cfun->expr->x_inhibit_defer_pop)
 165 #define saveregs_value (cfun->expr->x_saveregs_value)
 166 #define apply_args_value (cfun->expr->x_apply_args_value)
 167 #define forced_labels (cfun->expr->x_forced_labels)
 168 #define pending_chain (cfun->expr->x_pending_chain)
 169 #define stack_pointer_delta (cfun->expr->x_stack_pointer_delta)
 170
 171 /* This structure can save all the important global and static variables
 172    describing the status of the current function.  */
 173
 174 struct function
 175 {
 176   struct eh_status *eh;
 177   struct stmt_status *stmt;
 178   struct expr_status *expr;
 179   struct emit_status *emit;
 180   struct varasm_status *varasm;
 181
 182   /* For function.c.  */
 183
 184   /* Name of this function.  */
 185   const char *name;
 186
 187   /* Points to the FUNCTION_DECL of this function.  */
 188   tree decl;
 189
 190   /* Function containing this function, if any.  */
 191   struct function *outer;
 192
 193   /* Number of bytes of args popped by function being compiled on its return.
 194      Zero if no bytes are to be popped.
 195      May affect compilation of return insn or of function epilogue.  */
 196   int pops_args;
 197
 198   /* If function's args have a fixed size, this is that size, in bytes.
 199      Otherwise, it is -1.
 200      May affect compilation of return insn or of function epilogue.  */
 201   int args_size;
 202
 203   /* # bytes the prologue should push and pretend that the caller pushed them.
 204      The prologue must do this, but only if parms can be passed in
 205      registers.  */
 206   int pretend_args_size;
 207
 208   /* # of bytes of outgoing arguments.  If ACCUMULATE_OUTGOING_ARGS is
 209      defined, the needed space is pushed by the prologue.  */
 210   int outgoing_args_size;
 211
 212   /* This is the offset from the arg pointer to the place where the first
 213      anonymous arg can be found, if there is one.  */
 214   rtx arg_offset_rtx;
 215
 216   /* Quantities of various kinds of registers
 217      used for the current function's args.  */
 218   CUMULATIVE_ARGS args_info;
 219
 220   /* If non-zero, an RTL expression for the location at which the current
 221      function returns its result.  If the current function returns its
 222      result in a register, current_function_return_rtx will always be
 223      the hard register containing the result.  */
 224   rtx return_rtx;
 225
 226   /* The arg pointer hard register, or the pseudo into which it was copied.  */
 227   rtx internal_arg_pointer;
 228
 229   /* Language-specific reason why the current function cannot be made
 230      inline.  */
 231   const char *cannot_inline;
 232
 233   /* Opaque pointer used by get_hard_reg_initial_val and
 234      has_hard_reg_initial_val (see integrate.[hc]).  */
 235   struct initial_value_struct *hard_reg_initial_vals;
 236
 237   /* Number of function calls seen so far in current function.  */
 238   int x_function_call_count;
 239
 240   /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
 241      (labels to which there can be nonlocal gotos from nested functions)
 242      in this function.  */
 243   tree x_nonlocal_labels;
 244
 245   /* List (chain of EXPR_LIST) of stack slots that hold the current handlers
 246      for nonlocal gotos.  There is one for every nonlocal label in the
 247      function; this list matches the one in nonlocal_labels.
 248      Zero when function does not have nonlocal labels.  */
 249   rtx x_nonlocal_goto_handler_slots;
 250
 251   /* List (chain of EXPR_LIST) of labels heading the current handlers for
 252      nonlocal gotos.  */
 253   rtx x_nonlocal_goto_handler_labels;
 254
 255   /* RTX for stack slot that holds the stack pointer value to restore
 256      for a nonlocal goto.
 257      Zero when function does not have nonlocal labels.  */
 258   rtx x_nonlocal_goto_stack_level;
 259
 260   /* Label that will go on parm cleanup code, if any.
 261      Jumping to this label runs cleanup code for parameters, if
 262      such code must be run.  Following this code is the logical return
 263      label.  */
 264   rtx x_cleanup_label;
 265
 266   /* Label that will go on function epilogue.
 267      Jumping to this label serves as a "return" instruction
 268      on machines which require execution of the epilogue on all returns.  */
 269   rtx x_return_label;
 270
 271   /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
 272      So we can mark them all live at the end of the function, if nonopt.  */
 273   rtx x_save_expr_regs;
 274
 275   /* List (chain of EXPR_LISTs) of all stack slots in this function.
 276      Made for the sake of unshare_all_rtl.  */
 277   rtx x_stack_slot_list;
 278
 279   /* Chain of all RTL_EXPRs that have insns in them.  */
 280   tree x_rtl_expr_chain;
 281
 282   /* Label to jump back to for tail recursion, or 0 if we have
 283      not yet needed one for this function.  */
 284   rtx x_tail_recursion_label;
 285
 286   /* Place after which to insert the tail_recursion_label if we need one.  */
 287   rtx x_tail_recursion_reentry;
 288
 289   /* Location at which to save the argument pointer if it will need to be
 290      referenced.  There are two cases where this is done: if nonlocal gotos
 291      exist, or if vars stored at an offset from the argument pointer will be
 292      needed by inner routines.  */
 293   rtx x_arg_pointer_save_area;
 294
 295   /* If the function returns non-void, we will emit a clobber of the
 296      return registers just in case the user fell off the end without
 297      returning a proper value.  This is that insn.  */
 298   rtx x_clobber_return_insn;
 299
 300   /* Offset to end of allocated area of stack frame.
 301      If stack grows down, this is the address of the last stack slot allocated.
 302      If stack grows up, this is the address for the next slot.  */
 303   HOST_WIDE_INT x_frame_offset;
 304
 305   /* List (chain of TREE_LISTs) of static chains for containing functions.
 306      Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
 307      in an RTL_EXPR in the TREE_VALUE.  */
 308   tree x_context_display;
 309
 310   /* List (chain of TREE_LISTs) of trampolines for nested functions.
 311      The trampoline sets up the static chain and jumps to the function.
 312      We supply the trampoline's address when the function's address is
 313      requested.
 314
 315      Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
 316      in an RTL_EXPR in the TREE_VALUE.  */
 317   tree x_trampoline_list;
 318
 319   /* Insn after which register parms and SAVE_EXPRs are born, if nonopt.  */
 320   rtx x_parm_birth_insn;
 321
 322   /* Last insn of those whose job was to put parms into their nominal
 323      homes.  */
 324   rtx x_last_parm_insn;
 325
 326   /* 1 + last pseudo register number possibly used for loading a copy
 327      of a parameter of this function.  */
 328   unsigned int x_max_parm_reg;
 329
 330   /* Vector indexed by REGNO, containing location on stack in which
 331      to put the parm which is nominally in pseudo register REGNO,
 332      if we discover that that parm must go in the stack.  The highest
 333      element in this vector is one less than MAX_PARM_REG, above.  */
 334   rtx *x_parm_reg_stack_loc;
 335
 336   /* List of all temporaries allocated, both available and in use.  */
 337   struct temp_slot *x_temp_slots;
 338
 339   /* Current nesting level for temporaries.  */
 340   int x_temp_slot_level;
 341
 342   /* Current nesting level for variables in a block.  */
 343   int x_var_temp_slot_level;
 344
 345   /* When temporaries are created by TARGET_EXPRs, they are created at
 346      this level of temp_slot_level, so that they can remain allocated
 347      until no longer needed.  CLEANUP_POINT_EXPRs define the lifetime
 348      of TARGET_EXPRs.  */
 349   int x_target_temp_slot_level;
 350
 351   /* This slot is initialized as 0 and is added to
 352      during the nested function.  */
 353   struct var_refs_queue *fixup_var_refs_queue;
 354
 355   /* For integrate.c.  */
 356   int inlinable;
 357   int no_debugging_symbols;
 358   /* This is in fact an rtvec.  */
 359   void *original_arg_vector;
 360   tree original_decl_initial;
 361   /* Last insn of those whose job was to put parms into their nominal
 362      homes.  */
 363   rtx inl_last_parm_insn;
 364   /* Highest label number in current function.  */
 365   int inl_max_label_num;
 366
 367   /* For md files.  */
 368
 369   /* tm.h can use this to store whatever it likes.  */
 370   struct machine_function *machine;
 371   /* The largest alignment of slot allocated on the stack.  */
 372   int stack_alignment_needed;
 373   /* Preferred alignment of the end of stack frame.  */
 374   int preferred_stack_boundary;
 375
 376   /* Language-specific code can use this to store whatever it likes.  */
 377   struct language_function *language;
 378
 379   /* For reorg.  */
 380
 381   /* If some insns can be deferred to the delay slots of the epilogue, the
 382      delay list for them is recorded here.  */
 383   rtx epilogue_delay_list;
 384
 385   /* Collected bit flags.  */
 386
 387   /* Nonzero if function being compiled needs to be given an address
 388      where the value should be stored.  */
 389   unsigned int returns_struct : 1;
 390
 391   /* Nonzero if function being compiled needs to
 392      return the address of where it has put a structure value.  */
 393   unsigned int returns_pcc_struct : 1;
 394
 395   /* Nonzero if the current function returns a pointer type.  */
 396   unsigned int returns_pointer : 1;
 397
 398   /* Nonzero if function being compiled needs to be passed a static chain.  */
 399   unsigned int needs_context : 1;
 400
 401   /* Nonzero if function being compiled can call setjmp.  */
 402   unsigned int calls_setjmp : 1;
 403
 404   /* Nonzero if function being compiled can call longjmp.  */
 405   unsigned int calls_longjmp : 1;
 406
 407   /* Nonzero if function being compiled can call alloca,
 408      either as a subroutine or builtin.  */
 409   unsigned int calls_alloca : 1;
 410
 411   /* Nonzero if the function calls __builtin_eh_return.  */
 412   unsigned int calls_eh_return : 1;
 413
 414   /* Nonzero if function being compiled receives nonlocal gotos
 415      from nested functions.  */
 416   unsigned int has_nonlocal_label : 1;
 417
 418   /* Nonzero if function being compiled has nonlocal gotos to parent
 419      function.  */
 420   unsigned int has_nonlocal_goto : 1;
 421
 422   /* Nonzero if function being compiled contains nested functions.  */
 423   unsigned int contains_functions : 1;
 424
 425   /* Nonzero if the function being compiled issues a computed jump.  */
 426   unsigned int has_computed_jump : 1;
 427
 428   /* Nonzero if the current function is a thunk (a lightweight function that
 429      just adjusts one of its arguments and forwards to another function), so
 430      we should try to cut corners where we can.  */
 431   unsigned int is_thunk : 1;
 432
 433   /* Nonzero if instrumentation calls for function entry and exit should be
 434      generated.  */
 435   unsigned int instrument_entry_exit : 1;
 436
 437   /* Nonzero if profiling code should be generated.  */
 438   unsigned int profile : 1;
 439
 440   /* Nonzero if stack limit checking should be enabled in the current
 441      function.  */
 442   unsigned int limit_stack : 1;
 443
 444   /* Nonzero if current function uses varargs.h or equivalent.
 445      Zero for functions that use stdarg.h.  */
 446   unsigned int varargs : 1;
 447
 448   /* Nonzero if current function uses stdarg.h or equivalent.
 449      Zero for functions that use varargs.h.  */
 450   unsigned int stdarg : 1;
 451
 452   /* Nonzero if this function is being processed in function-at-a-time
 453      mode.  In other words, if all tree structure for this function,
 454      including the BLOCK tree, is created before RTL generation
 455      commences.  */
 456   unsigned int x_whole_function_mode_p : 1;
 457
 458   /* Nonzero if the back-end should not keep track of expressions that
 459      determine the size of variable-sized objects.  Normally, such
 460      expressions are saved away, and then expanded when the next
 461      function is started.  For example, if a parameter has a
 462      variable-sized type, then the size of the parameter is computed
 463      when the function body is entered.  However, some front-ends do
 464      not desire this behavior.  */
 465   unsigned int x_dont_save_pending_sizes_p : 1;
 466
 467   /* Nonzero if the current function uses the constant pool.  */
 468   unsigned int uses_const_pool : 1;
 469
 470   /* Nonzero if the current function uses pic_offset_table_rtx.  */
 471   unsigned int uses_pic_offset_table : 1;
 472
 473   /* Nonzero if the current function needs an lsda for exception handling.  */
 474   unsigned int uses_eh_lsda : 1;
 475
 476   /* Nonzero if code to initialize arg_pointer_save_area has been emited.  */
 477   unsigned int arg_pointer_save_area_init : 1;
 478 };
 479
 480 /* The function currently being compiled.  */
 481 extern struct function *cfun;
 482
 483 /* Nonzero if we've already converted virtual regs to hard regs.  */
 484 extern int virtuals_instantiated;
 485
 486 /* For backward compatibility... eventually these should all go away.  */
 487 #define current_function_name (cfun->name)
 488 #define current_function_pops_args (cfun->pops_args)
 489 #define current_function_returns_struct (cfun->returns_struct)
 490 #define current_function_returns_pcc_struct (cfun->returns_pcc_struct)
 491 #define current_function_returns_pointer (cfun->returns_pointer)
 492 #define current_function_needs_context (cfun->needs_context)
 493 #define current_function_calls_setjmp (cfun->calls_setjmp)
 494 #define current_function_calls_alloca (cfun->calls_alloca)
 495 #define current_function_calls_longjmp (cfun->calls_longjmp)
 496 #define current_function_calls_eh_return (cfun->calls_eh_return)
 497 #define current_function_has_computed_jump (cfun->has_computed_jump)
 498 #define current_function_contains_functions (cfun->contains_functions)
 499 #define current_function_is_thunk (cfun->is_thunk)
 500 #define current_function_args_info (cfun->args_info)
 501 #define current_function_args_size (cfun->args_size)
 502 #define current_function_pretend_args_size (cfun->pretend_args_size)
 503 #define current_function_outgoing_args_size (cfun->outgoing_args_size)
 504 #define current_function_arg_offset_rtx (cfun->arg_offset_rtx)
 505 #define current_function_varargs (cfun->varargs)
 506 #define current_function_stdarg (cfun->stdarg)
 507 #define current_function_internal_arg_pointer (cfun->internal_arg_pointer)
 508 #define current_function_return_rtx (cfun->return_rtx)
 509 #define current_function_instrument_entry_exit (cfun->instrument_entry_exit)
 510 #define current_function_profile (cfun->profile)
 511 #define current_function_limit_stack (cfun->limit_stack)
 512 #define current_function_uses_pic_offset_table (cfun->uses_pic_offset_table)
 513 #define current_function_uses_const_pool (cfun->uses_const_pool)
 514 #define current_function_cannot_inline (cfun->cannot_inline)
 515 #define current_function_epilogue_delay_list (cfun->epilogue_delay_list)
 516 #define current_function_has_nonlocal_label (cfun->has_nonlocal_label)
 517 #define current_function_has_nonlocal_goto (cfun->has_nonlocal_goto)
 518
 519 #define max_parm_reg (cfun->x_max_parm_reg)
 520 #define parm_reg_stack_loc (cfun->x_parm_reg_stack_loc)
 521 #define cleanup_label (cfun->x_cleanup_label)
 522 #define return_label (cfun->x_return_label)
 523 #define save_expr_regs (cfun->x_save_expr_regs)
 524 #define stack_slot_list (cfun->x_stack_slot_list)
 525 #define parm_birth_insn (cfun->x_parm_birth_insn)
 526 #define frame_offset (cfun->x_frame_offset)
 527 #define tail_recursion_label (cfun->x_tail_recursion_label)
 528 #define tail_recursion_reentry (cfun->x_tail_recursion_reentry)
 529 #define arg_pointer_save_area (cfun->x_arg_pointer_save_area)
 530 #define rtl_expr_chain (cfun->x_rtl_expr_chain)
 531 #define last_parm_insn (cfun->x_last_parm_insn)
 532 #define context_display (cfun->x_context_display)
 533 #define trampoline_list (cfun->x_trampoline_list)
 534 #define function_call_count (cfun->x_function_call_count)
 535 #define temp_slots (cfun->x_temp_slots)
 536 #define temp_slot_level (cfun->x_temp_slot_level)
 537 #define target_temp_slot_level (cfun->x_target_temp_slot_level)
 538 #define var_temp_slot_level (cfun->x_var_temp_slot_level)
 539 #define nonlocal_labels (cfun->x_nonlocal_labels)
 540 #define nonlocal_goto_handler_slots (cfun->x_nonlocal_goto_handler_slots)
 541 #define nonlocal_goto_handler_labels (cfun->x_nonlocal_goto_handler_labels)
 542 #define nonlocal_goto_stack_level (cfun->x_nonlocal_goto_stack_level)
 543
 544 /* The FUNCTION_DECL for an inline function currently being expanded.  */
 545 extern tree inline_function_decl;
 546
 547 /* Given a function decl for a containing function,
 548    return the `struct function' for it.  */
 549 struct function *find_function_data PARAMS ((tree));
 550
 551 /* Set NOTE_BLOCK for each block note in the current function.  */
 552 extern void identify_blocks PARAMS ((void));
 553
 554 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
 555    and create duplicate blocks.  */
 556 extern void reorder_blocks PARAMS ((void));
 557
 558 /* Set BLOCK_NUMBER for all the blocks in FN.  */
 559 extern void number_blocks PARAMS ((tree));
 560
 561 /* Return size needed for stack frame based on slots so far allocated.
 562    This size counts from zero.  It is not rounded to STACK_BOUNDARY;
 563    the caller may have to do that.  */
 564 extern HOST_WIDE_INT get_frame_size     PARAMS ((void));
 565 /* Likewise, but for a different than the current function.  */
 566 extern HOST_WIDE_INT get_func_frame_size        PARAMS ((struct function *));
 567
 568 /* These variables hold pointers to functions to create and destroy
 569    target specific, per-function data structures.  */
 570 extern void (*init_machine_status)      PARAMS ((struct function *));
 571 extern void (*free_machine_status)      PARAMS ((struct function *));
 572 /* This variable holds a pointer to a function to register any
 573    data items in the target specific, per-function data structure
 574    that will need garbage collection.  */
 575 extern void (*mark_machine_status)      PARAMS ((struct function *));
 576
 577 /* Likewise, but for language-specific data.  */
 578 extern void (*init_lang_status)         PARAMS ((struct function *));
 579 extern void (*mark_lang_status)         PARAMS ((struct function *));
 580 extern void (*save_lang_status)         PARAMS ((struct function *));
 581 extern void (*restore_lang_status)      PARAMS ((struct function *));
 582 extern void (*free_lang_status)         PARAMS ((struct function *));
 583
 584 /* Save and restore status information for a nested 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 rtx get_arg_pointer_save_area    PARAMS ((struct function *));
 605
 606 extern void init_virtual_regs           PARAMS ((struct emit_status *));
 607
 608 /* Called once, at initialization, to initialize function.c.  */
 609 extern void init_function_once          PARAMS ((void));