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
  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, regno_decl, and x_regno_reg_rtx
 101      vectors.  Since these vectors are needed during the expansion phase when
 102      the total number of registers in the function is not yet known, the
 103      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, if nonzero gives the decl
 112      corresponding to that register.  */
 113   tree *regno_decl;
 114
 115   /* Indexed by pseudo register number, gives the rtx for that pseudo.
 116      Allocated in parallel with regno_pointer_align.  */
 117   rtx *x_regno_reg_rtx;
 118 };
 119
 120 /* For backward compatibility... eventually these should all go away.  */
 121 #define reg_rtx_no (cfun->emit->x_reg_rtx_no)
 122 #define seq_rtl_expr (cfun->emit->sequence_rtl_expr)
 123 #define regno_reg_rtx (cfun->emit->x_regno_reg_rtx)
 124 #define seq_stack (cfun->emit->sequence_stack)
 125
 126 #define REGNO_POINTER_ALIGN(REGNO) (cfun->emit->regno_pointer_align[REGNO])
 127 #define REGNO_DECL(REGNO) (cfun->emit->regno_decl[REGNO])
 128
 129 struct expr_status
 130 {
 131   /* Number of units that we should eventually pop off the stack.
 132      These are the arguments to function calls that have already returned.  */
 133   int x_pending_stack_adjust;
 134
 135   /* Under some ABIs, it is the caller's responsibility to pop arguments
 136      pushed for function calls.  A naive implementation would simply pop
 137      the arguments immediately after each call.  However, if several
 138      function calls are made in a row, it is typically cheaper to pop
 139      all the arguments after all of the calls are complete since a
 140      single pop instruction can be used.  Therefore, GCC attempts to
 141      defer popping the arguments until absolutely necessary.  (For
 142      example, at the end of a conditional, the arguments must be popped,
 143      since code outside the conditional won't know whether or not the
 144      arguments need to be popped.)
 145
 146      When INHIBIT_DEFER_POP is non-zero, however, the compiler does not
 147      attempt to defer pops.  Instead, the stack is popped immediately
 148      after each call.  Rather then setting this variable directly, use
 149      NO_DEFER_POP and OK_DEFER_POP.  */
 150   int x_inhibit_defer_pop;
 151
 152   /* If PREFERRED_STACK_BOUNDARY and PUSH_ROUNDING are defined, the stack
 153      boundary can be momentairly unaligned while pushing the arguments.
 154      Record the delta since last aligned boundary here in order to get
 155      stack alignment in the nested function calls working right.  */
 156   int x_stack_pointer_delta;
 157
 158   /* Nonzero means __builtin_saveregs has already been done in this function.
 159      The value is the pseudoreg containing the value __builtin_saveregs
 160      returned.  */
 161   rtx x_saveregs_value;
 162
 163   /* Similarly for __builtin_apply_args.  */
 164   rtx x_apply_args_value;
 165
 166   /* List of labels that must never be deleted.  */
 167   rtx x_forced_labels;
 168
 169   /* Postincrements that still need to be expanded.  */
 170   rtx x_pending_chain;
 171 };
 172
 173 #define pending_stack_adjust (cfun->expr->x_pending_stack_adjust)
 174 #define inhibit_defer_pop (cfun->expr->x_inhibit_defer_pop)
 175 #define saveregs_value (cfun->expr->x_saveregs_value)
 176 #define apply_args_value (cfun->expr->x_apply_args_value)
 177 #define forced_labels (cfun->expr->x_forced_labels)
 178 #define pending_chain (cfun->expr->x_pending_chain)
 179 #define stack_pointer_delta (cfun->expr->x_stack_pointer_delta)
 180
 181 /* This structure can save all the important global and static variables
 182    describing the status of the current function.  */
 183
 184 struct function
 185 {
 186   struct eh_status *eh;
 187   struct stmt_status *stmt;
 188   struct expr_status *expr;
 189   struct emit_status *emit;
 190   struct varasm_status *varasm;
 191
 192   /* For function.c.  */
 193
 194   /* Name of this function.  */
 195   const char *name;
 196
 197   /* Points to the FUNCTION_DECL of this function.  */
 198   tree decl;
 199
 200   /* Function containing this function, if any.  */
 201   struct function *outer;
 202
 203   /* Number of bytes of args popped by function being compiled on its return.
 204      Zero if no bytes are to be popped.
 205      May affect compilation of return insn or of function epilogue.  */
 206   int pops_args;
 207
 208   /* If function's args have a fixed size, this is that size, in bytes.
 209      Otherwise, it is -1.
 210      May affect compilation of return insn or of function epilogue.  */
 211   int args_size;
 212
 213   /* # bytes the prologue should push and pretend that the caller pushed them.
 214      The prologue must do this, but only if parms can be passed in
 215      registers.  */
 216   int pretend_args_size;
 217
 218   /* # of bytes of outgoing arguments.  If ACCUMULATE_OUTGOING_ARGS is
 219      defined, the needed space is pushed by the prologue.  */
 220   int outgoing_args_size;
 221
 222   /* This is the offset from the arg pointer to the place where the first
 223      anonymous arg can be found, if there is one.  */
 224   rtx arg_offset_rtx;
 225
 226   /* Quantities of various kinds of registers
 227      used for the current function's args.  */
 228   CUMULATIVE_ARGS args_info;
 229
 230   /* If non-zero, an RTL expression for the location at which the current
 231      function returns its result.  If the current function returns its
 232      result in a register, current_function_return_rtx will always be
 233      the hard register containing the result.  */
 234   rtx return_rtx;
 235
 236   /* The arg pointer hard register, or the pseudo into which it was copied.  */
 237   rtx internal_arg_pointer;
 238
 239   /* Language-specific reason why the current function cannot be made
 240      inline.  */
 241   const char *cannot_inline;
 242
 243   /* Opaque pointer used by get_hard_reg_initial_val and
 244      has_hard_reg_initial_val (see integrate.[hc]).  */
 245   struct initial_value_struct *hard_reg_initial_vals;
 246
 247   /* Number of function calls seen so far in current function.  */
 248   int x_function_call_count;
 249
 250   /* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
 251      (labels to which there can be nonlocal gotos from nested functions)
 252      in this function.  */
 253   tree x_nonlocal_labels;
 254
 255   /* List (chain of EXPR_LIST) of stack slots that hold the current handlers
 256      for nonlocal gotos.  There is one for every nonlocal label in the
 257      function; this list matches the one in nonlocal_labels.
 258      Zero when function does not have nonlocal labels.  */
 259   rtx x_nonlocal_goto_handler_slots;
 260
 261   /* List (chain of EXPR_LIST) of labels heading the current handlers for
 262      nonlocal gotos.  */
 263   rtx x_nonlocal_goto_handler_labels;
 264
 265   /* RTX for stack slot that holds the stack pointer value to restore
 266      for a nonlocal goto.
 267      Zero when function does not have nonlocal labels.  */
 268   rtx x_nonlocal_goto_stack_level;
 269
 270   /* Label that will go on parm cleanup code, if any.
 271      Jumping to this label runs cleanup code for parameters, if
 272      such code must be run.  Following this code is the logical return
 273      label.  */
 274   rtx x_cleanup_label;
 275
 276   /* Label that will go on function epilogue.
 277      Jumping to this label serves as a "return" instruction
 278      on machines which require execution of the epilogue on all returns.  */
 279   rtx x_return_label;
 280
 281   /* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
 282      So we can mark them all live at the end of the function, if nonopt.  */
 283   rtx x_save_expr_regs;
 284
 285   /* List (chain of EXPR_LISTs) of all stack slots in this function.
 286      Made for the sake of unshare_all_rtl.  */
 287   rtx x_stack_slot_list;
 288
 289   /* Chain of all RTL_EXPRs that have insns in them.  */
 290   tree x_rtl_expr_chain;
 291
 292   /* Label to jump back to for tail recursion, or 0 if we have
 293      not yet needed one for this function.  */
 294   rtx x_tail_recursion_label;
 295
 296   /* Place after which to insert the tail_recursion_label if we need one.  */
 297   rtx x_tail_recursion_reentry;
 298
 299   /* Location at which to save the argument pointer if it will need to be
 300      referenced.  There are two cases where this is done: if nonlocal gotos
 301      exist, or if vars stored at an offset from the argument pointer will be
 302      needed by inner routines.  */
 303   rtx x_arg_pointer_save_area;
 304
 305   /* If the function returns non-void, we will emit a clobber of the
 306      return registers just in case the user fell off the end without
 307      returning a proper value.  This is that insn.  */
 308   rtx x_clobber_return_insn;
 309
 310   /* Offset to end of allocated area of stack frame.
 311      If stack grows down, this is the address of the last stack slot allocated.
 312      If stack grows up, this is the address for the next slot.  */
 313   HOST_WIDE_INT x_frame_offset;
 314
 315   /* List (chain of TREE_LISTs) of static chains for containing functions.
 316      Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
 317      in an RTL_EXPR in the TREE_VALUE.  */
 318   tree x_context_display;
 319
 320   /* List (chain of TREE_LISTs) of trampolines for nested functions.
 321      The trampoline sets up the static chain and jumps to the function.
 322      We supply the trampoline's address when the function's address is
 323      requested.
 324
 325      Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
 326      in an RTL_EXPR in the TREE_VALUE.  */
 327   tree x_trampoline_list;
 328
 329   /* Insn after which register parms and SAVE_EXPRs are born, if nonopt.  */
 330   rtx x_parm_birth_insn;
 331
 332   /* Last insn of those whose job was to put parms into their nominal
 333      homes.  */
 334   rtx x_last_parm_insn;
 335
 336   /* 1 + last pseudo register number possibly used for loading a copy
 337      of a parameter of this function.  */
 338   unsigned int x_max_parm_reg;
 339
 340   /* Vector indexed by REGNO, containing location on stack in which
 341      to put the parm which is nominally in pseudo register REGNO,
 342      if we discover that that parm must go in the stack.  The highest
 343      element in this vector is one less than MAX_PARM_REG, above.  */
 344   rtx *x_parm_reg_stack_loc;
 345
 346   /* List of all temporaries allocated, both available and in use.  */
 347   struct temp_slot *x_temp_slots;
 348
 349   /* Current nesting level for temporaries.  */
 350   int x_temp_slot_level;
 351
 352   /* Current nesting level for variables in a block.  */
 353   int x_var_temp_slot_level;
 354
 355   /* When temporaries are created by TARGET_EXPRs, they are created at
 356      this level of temp_slot_level, so that they can remain allocated
 357      until no longer needed.  CLEANUP_POINT_EXPRs define the lifetime
 358      of TARGET_EXPRs.  */
 359   int x_target_temp_slot_level;
 360
 361   /* This slot is initialized as 0 and is added to
 362      during the nested function.  */
 363   struct var_refs_queue *fixup_var_refs_queue;
 364
 365   /* For integrate.c.  */
 366   int inlinable;
 367   int no_debugging_symbols;
 368   /* This is in fact an rtvec.  */
 369   void *original_arg_vector;
 370   tree original_decl_initial;
 371   /* Last insn of those whose job was to put parms into their nominal
 372      homes.  */
 373   rtx inl_last_parm_insn;
 374   /* Highest label number in current function.  */
 375   int inl_max_label_num;
 376
 377   /* For md files.  */
 378
 379   /* tm.h can use this to store whatever it likes.  */
 380   struct machine_function *machine;
 381   /* The largest alignment of slot allocated on the stack.  */
 382   int stack_alignment_needed;
 383   /* Preferred alignment of the end of stack frame.  */
 384   int preferred_stack_boundary;
 385
 386   /* Language-specific code can use this to store whatever it likes.  */
 387   struct language_function *language;
 388
 389   /* For reorg.  */
 390
 391   /* If some insns can be deferred to the delay slots of the epilogue, the
 392      delay list for them is recorded here.  */
 393   rtx epilogue_delay_list;
 394
 395   /* Collected bit flags.  */
 396
 397   /* Nonzero if function being compiled needs to be given an address
 398      where the value should be stored.  */
 399   unsigned int returns_struct : 1;
 400
 401   /* Nonzero if function being compiled needs to
 402      return the address of where it has put a structure value.  */
 403   unsigned int returns_pcc_struct : 1;
 404
 405   /* Nonzero if the current function returns a pointer type.  */
 406   unsigned int returns_pointer : 1;
 407
 408   /* Nonzero if function being compiled needs to be passed a static chain.  */
 409   unsigned int needs_context : 1;
 410
 411   /* Nonzero if function being compiled can call setjmp.  */
 412   unsigned int calls_setjmp : 1;
 413
 414   /* Nonzero if function being compiled can call longjmp.  */
 415   unsigned int calls_longjmp : 1;
 416
 417   /* Nonzero if function being compiled can call alloca,
 418      either as a subroutine or builtin.  */
 419   unsigned int calls_alloca : 1;
 420
 421   /* Nonzero if the function calls __builtin_eh_return.  */
 422   unsigned int calls_eh_return : 1;
 423
 424   /* Nonzero if function being compiled receives nonlocal gotos
 425      from nested functions.  */
 426   unsigned int has_nonlocal_label : 1;
 427
 428   /* Nonzero if function being compiled has nonlocal gotos to parent
 429      function.  */
 430   unsigned int has_nonlocal_goto : 1;
 431
 432   /* Nonzero if function being compiled contains nested functions.  */
 433   unsigned int contains_functions : 1;
 434
 435   /* Nonzero if the function being compiled issues a computed jump.  */
 436   unsigned int has_computed_jump : 1;
 437
 438   /* Nonzero if the current function is a thunk (a lightweight function that
 439      just adjusts one of its arguments and forwards to another function), so
 440      we should try to cut corners where we can.  */
 441   unsigned int is_thunk : 1;
 442
 443   /* Nonzero if instrumentation calls for function entry and exit should be
 444      generated.  */
 445   unsigned int instrument_entry_exit : 1;
 446
 447   /* Nonzero if memory access checking be enabled in the current function.  */
 448   unsigned int check_memory_usage : 1;
 449
 450   /* Nonzero if stack limit checking should be enabled in the current
 451      function.  */
 452   unsigned int limit_stack : 1;
 453
 454   /* Nonzero if current function uses varargs.h or equivalent.
 455      Zero for functions that use stdarg.h.  */
 456   unsigned int varargs : 1;
 457
 458   /* Nonzero if current function uses stdarg.h or equivalent.
 459      Zero for functions that use varargs.h.  */
 460   unsigned int stdarg : 1;
 461
 462   /* Nonzero if this function is being processed in function-at-a-time
 463      mode.  In other words, if all tree structure for this function,
 464      including the BLOCK tree, is created before RTL generation
 465      commences.  */
 466   unsigned int x_whole_function_mode_p : 1;
 467
 468   /* Nonzero if the back-end should not keep track of expressions that
 469      determine the size of variable-sized objects.  Normally, such
 470      expressions are saved away, and then expanded when the next
 471      function is started.  For example, if a parameter has a
 472      variable-sized type, then the size of the parameter is computed
 473      when the function body is entered.  However, some front-ends do
 474      not desire this behavior.  */
 475   unsigned int x_dont_save_pending_sizes_p : 1;
 476
 477   /* Nonzero if the current function uses the constant pool.  */
 478   unsigned int uses_const_pool : 1;
 479
 480   /* Nonzero if the current function uses pic_offset_table_rtx.  */
 481   unsigned int uses_pic_offset_table : 1;
 482
 483   /* Nonzero if the current function needs an lsda for exception handling.  */
 484   unsigned int uses_eh_lsda : 1;
 485
 486   /* Nonzero if code to initialize arg_pointer_save_area has been emited.  */
 487   unsigned int arg_pointer_save_area_init : 1;
 488 };
 489
 490 /* The function currently being compiled.  */
 491 extern struct function *cfun;
 492
 493 /* Nonzero if we've already converted virtual regs to hard regs.  */
 494 extern int virtuals_instantiated;
 495
 496 /* For backward compatibility... eventually these should all go away.  */
 497 #define current_function_name (cfun->name)
 498 #define current_function_pops_args (cfun->pops_args)
 499 #define current_function_returns_struct (cfun->returns_struct)
 500 #define current_function_returns_pcc_struct (cfun->returns_pcc_struct)
 501 #define current_function_returns_pointer (cfun->returns_pointer)
 502 #define current_function_needs_context (cfun->needs_context)
 503 #define current_function_calls_setjmp (cfun->calls_setjmp)
 504 #define current_function_calls_alloca (cfun->calls_alloca)
 505 #define current_function_calls_longjmp (cfun->calls_longjmp)
 506 #define current_function_calls_eh_return (cfun->calls_eh_return)
 507 #define current_function_has_computed_jump (cfun->has_computed_jump)
 508 #define current_function_contains_functions (cfun->contains_functions)
 509 #define current_function_is_thunk (cfun->is_thunk)
 510 #define current_function_args_info (cfun->args_info)
 511 #define current_function_args_size (cfun->args_size)
 512 #define current_function_pretend_args_size (cfun->pretend_args_size)
 513 #define current_function_outgoing_args_size (cfun->outgoing_args_size)
 514 #define current_function_arg_offset_rtx (cfun->arg_offset_rtx)
 515 #define current_function_varargs (cfun->varargs)
 516 #define current_function_stdarg (cfun->stdarg)
 517 #define current_function_internal_arg_pointer (cfun->internal_arg_pointer)
 518 #define current_function_return_rtx (cfun->return_rtx)
 519 #define current_function_instrument_entry_exit (cfun->instrument_entry_exit)
 520 #define current_function_check_memory_usage (cfun->check_memory_usage)
 521 #define current_function_limit_stack (cfun->limit_stack)
 522 #define current_function_uses_pic_offset_table (cfun->uses_pic_offset_table)
 523 #define current_function_uses_const_pool (cfun->uses_const_pool)
 524 #define current_function_cannot_inline (cfun->cannot_inline)
 525 #define current_function_epilogue_delay_list (cfun->epilogue_delay_list)
 526 #define current_function_has_nonlocal_label (cfun->has_nonlocal_label)
 527 #define current_function_has_nonlocal_goto (cfun->has_nonlocal_goto)
 528
 529 #define max_parm_reg (cfun->x_max_parm_reg)
 530 #define parm_reg_stack_loc (cfun->x_parm_reg_stack_loc)
 531 #define cleanup_label (cfun->x_cleanup_label)
 532 #define return_label (cfun->x_return_label)
 533 #define save_expr_regs (cfun->x_save_expr_regs)
 534 #define stack_slot_list (cfun->x_stack_slot_list)
 535 #define parm_birth_insn (cfun->x_parm_birth_insn)
 536 #define frame_offset (cfun->x_frame_offset)
 537 #define tail_recursion_label (cfun->x_tail_recursion_label)
 538 #define tail_recursion_reentry (cfun->x_tail_recursion_reentry)
 539 #define arg_pointer_save_area (cfun->x_arg_pointer_save_area)
 540 #define rtl_expr_chain (cfun->x_rtl_expr_chain)
 541 #define last_parm_insn (cfun->x_last_parm_insn)
 542 #define context_display (cfun->x_context_display)
 543 #define trampoline_list (cfun->x_trampoline_list)
 544 #define function_call_count (cfun->x_function_call_count)
 545 #define temp_slots (cfun->x_temp_slots)
 546 #define temp_slot_level (cfun->x_temp_slot_level)
 547 #define target_temp_slot_level (cfun->x_target_temp_slot_level)
 548 #define var_temp_slot_level (cfun->x_var_temp_slot_level)
 549 #define nonlocal_labels (cfun->x_nonlocal_labels)
 550 #define nonlocal_goto_handler_slots (cfun->x_nonlocal_goto_handler_slots)
 551 #define nonlocal_goto_handler_labels (cfun->x_nonlocal_goto_handler_labels)
 552 #define nonlocal_goto_stack_level (cfun->x_nonlocal_goto_stack_level)
 553
 554 /* The FUNCTION_DECL for an inline function currently being expanded.  */
 555 extern tree inline_function_decl;
 556
 557 /* Given a function decl for a containing function,
 558    return the `struct function' for it.  */
 559 struct function *find_function_data PARAMS ((tree));
 560
 561 /* Set NOTE_BLOCK for each block note in the current function.  */
 562 extern void identify_blocks PARAMS ((void));
 563
 564 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
 565    and create duplicate blocks.  */
 566 extern void reorder_blocks PARAMS ((void));
 567
 568 /* Set BLOCK_NUMBER for all the blocks in FN.  */
 569 extern void number_blocks PARAMS ((tree));
 570
 571 /* Return size needed for stack frame based on slots so far allocated.
 572    This size counts from zero.  It is not rounded to STACK_BOUNDARY;
 573    the caller may have to do that.  */
 574 extern HOST_WIDE_INT get_frame_size     PARAMS ((void));
 575 /* Likewise, but for a different than the current function.  */
 576 extern HOST_WIDE_INT get_func_frame_size        PARAMS ((struct function *));
 577
 578 /* These variables hold pointers to functions to create and destroy
 579    target specific, per-function data structures.  */
 580 extern void (*init_machine_status)      PARAMS ((struct function *));
 581 extern void (*free_machine_status)      PARAMS ((struct function *));
 582 /* This variable holds a pointer to a function to register any
 583    data items in the target specific, per-function data structure
 584    that will need garbage collection.  */
 585 extern void (*mark_machine_status)      PARAMS ((struct function *));
 586
 587 /* Likewise, but for language-specific data.  */
 588 extern void (*init_lang_status)         PARAMS ((struct function *));
 589 extern void (*mark_lang_status)         PARAMS ((struct function *));
 590 extern void (*save_lang_status)         PARAMS ((struct function *));
 591 extern void (*restore_lang_status)      PARAMS ((struct function *));
 592 extern void (*free_lang_status)         PARAMS ((struct function *));
 593
 594 /* Save and restore status information for a nested function.  */
 595 extern void restore_emit_status         PARAMS ((struct function *));
 596 extern void free_after_parsing          PARAMS ((struct function *));
 597 extern void free_after_compilation      PARAMS ((struct function *));
 598
 599 extern void init_varasm_status          PARAMS ((struct function *));
 600 extern void restore_varasm_status       PARAMS ((struct function *));
 601 extern void free_varasm_status          PARAMS ((struct function *));
 602 extern void free_emit_status            PARAMS ((struct function *));
 603 extern void free_stmt_status            PARAMS ((struct function *));
 604 extern void free_eh_status              PARAMS ((struct function *));
 605 extern void free_expr_status            PARAMS ((struct function *));
 606
 607 extern rtx get_first_block_beg          PARAMS ((void));
 608
 609 #ifdef RTX_CODE
 610 extern void diddle_return_value         PARAMS ((void (*)(rtx, void*), void*));
 611 extern void clobber_return_register     PARAMS ((void));
 612 extern void use_return_register         PARAMS ((void));
 613 #endif
 614
 615 extern rtx get_arg_pointer_save_area    PARAMS ((struct function *));
 616
 617 extern void init_virtual_regs           PARAMS ((struct emit_status *));
 618
 619 /* Called once, at initialization, to initialize function.c.  */
 620 extern void init_function_once          PARAMS ((void));
 621
 622 #ifdef rtx
 623 #undef rtx
 624 #endif
 625
 626 #ifdef tree
 627 #undef tree
 628 #endif