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1 /* Structure for saving state for a nested function.
2 Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
5
6 This file is part of GCC.
7
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
12
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
21
22 #ifndef GCC_FUNCTION_H
23 #define GCC_FUNCTION_H
24
25 #include "tree.h"
26 #include "hashtab.h"
27 #include "vecprim.h"
28 #include "tm.h" /* For CUMULATIVE_ARGS. */
29 #include "hard-reg-set.h"
30
31 /* Stack of pending (incomplete) sequences saved by `start_sequence'.
32 Each element describes one pending sequence.
33 The main insn-chain is saved in the last element of the chain,
34 unless the chain is empty. */
35
36 struct GTY(()) sequence_stack {
37 /* First and last insns in the chain of the saved sequence. */
38 rtx first;
39 rtx last;
40 struct sequence_stack *next;
41 };
42 \f
43 struct GTY(()) emit_status {
44 /* This is reset to LAST_VIRTUAL_REGISTER + 1 at the start of each function.
45 After rtl generation, it is 1 plus the largest register number used. */
46 int x_reg_rtx_no;
47
48 /* Lowest label number in current function. */
49 int x_first_label_num;
50
51 /* The ends of the doubly-linked chain of rtl for the current function.
52 Both are reset to null at the start of rtl generation for the function.
53
54 start_sequence saves both of these on `sequence_stack' and then starts
55 a new, nested sequence of insns. */
56 rtx x_first_insn;
57 rtx x_last_insn;
58
59 /* Stack of pending (incomplete) sequences saved by `start_sequence'.
60 Each element describes one pending sequence.
61 The main insn-chain is saved in the last element of the chain,
62 unless the chain is empty. */
63 struct sequence_stack *sequence_stack;
64
65 /* INSN_UID for next insn emitted.
66 Reset to 1 for each function compiled. */
67 int x_cur_insn_uid;
68
69 /* INSN_UID for next debug insn emitted. Only used if
70 --param min-nondebug-insn-uid=<value> is given with nonzero value. */
71 int x_cur_debug_insn_uid;
72
73 /* Location the last line-number NOTE emitted.
74 This is used to avoid generating duplicates. */
75 location_t x_last_location;
76
77 /* The length of the regno_pointer_align, regno_decl, and x_regno_reg_rtx
78 vectors. Since these vectors are needed during the expansion phase when
79 the total number of registers in the function is not yet known, the
80 vectors are copied and made bigger when necessary. */
81 int regno_pointer_align_length;
82
83 /* Indexed by pseudo register number, if nonzero gives the known alignment
84 for that pseudo (if REG_POINTER is set in x_regno_reg_rtx).
85 Allocated in parallel with x_regno_reg_rtx. */
86 unsigned char * GTY((skip)) regno_pointer_align;
87 };
88
89
90 /* Indexed by pseudo register number, gives the rtx for that pseudo.
91 Allocated in parallel with regno_pointer_align.
92 FIXME: We could put it into emit_status struct, but gengtype is not able to deal
93 with length attribute nested in top level structures. */
94
95 extern GTY ((length ("crtl->emit.x_reg_rtx_no"))) rtx * regno_reg_rtx;
96
97 /* For backward compatibility... eventually these should all go away. */
98 #define reg_rtx_no (crtl->emit.x_reg_rtx_no)
99 #define seq_stack (crtl->emit.sequence_stack)
100
101 #define REGNO_POINTER_ALIGN(REGNO) (crtl->emit.regno_pointer_align[REGNO])
102
103 struct GTY(()) expr_status {
104 /* Number of units that we should eventually pop off the stack.
105 These are the arguments to function calls that have already returned. */
106 int x_pending_stack_adjust;
107
108 /* Under some ABIs, it is the caller's responsibility to pop arguments
109 pushed for function calls. A naive implementation would simply pop
110 the arguments immediately after each call. However, if several
111 function calls are made in a row, it is typically cheaper to pop
112 all the arguments after all of the calls are complete since a
113 single pop instruction can be used. Therefore, GCC attempts to
114 defer popping the arguments until absolutely necessary. (For
115 example, at the end of a conditional, the arguments must be popped,
116 since code outside the conditional won't know whether or not the
117 arguments need to be popped.)
118
119 When INHIBIT_DEFER_POP is nonzero, however, the compiler does not
120 attempt to defer pops. Instead, the stack is popped immediately
121 after each call. Rather then setting this variable directly, use
122 NO_DEFER_POP and OK_DEFER_POP. */
123 int x_inhibit_defer_pop;
124
125 /* If PREFERRED_STACK_BOUNDARY and PUSH_ROUNDING are defined, the stack
126 boundary can be momentarily unaligned while pushing the arguments.
127 Record the delta since last aligned boundary here in order to get
128 stack alignment in the nested function calls working right. */
129 int x_stack_pointer_delta;
130
131 /* Nonzero means __builtin_saveregs has already been done in this function.
132 The value is the pseudoreg containing the value __builtin_saveregs
133 returned. */
134 rtx x_saveregs_value;
135
136 /* Similarly for __builtin_apply_args. */
137 rtx x_apply_args_value;
138
139 /* List of labels that must never be deleted. */
140 rtx x_forced_labels;
141 };
142
143 typedef struct call_site_record_d *call_site_record;
144 DEF_VEC_P(call_site_record);
145 DEF_VEC_ALLOC_P(call_site_record, gc);
146
147 /* RTL representation of exception handling. */
148 struct GTY(()) rtl_eh {
149 rtx ehr_stackadj;
150 rtx ehr_handler;
151 rtx ehr_label;
152
153 rtx sjlj_fc;
154 rtx sjlj_exit_after;
155
156 VEC(uchar,gc) *action_record_data;
157
158 VEC(call_site_record,gc) *call_site_record[2];
159 };
160
161 #define pending_stack_adjust (crtl->expr.x_pending_stack_adjust)
162 #define inhibit_defer_pop (crtl->expr.x_inhibit_defer_pop)
163 #define saveregs_value (crtl->expr.x_saveregs_value)
164 #define apply_args_value (crtl->expr.x_apply_args_value)
165 #define forced_labels (crtl->expr.x_forced_labels)
166 #define stack_pointer_delta (crtl->expr.x_stack_pointer_delta)
167
168 struct gimple_df;
169 struct temp_slot;
170 typedef struct temp_slot *temp_slot_p;
171 struct call_site_record_d;
172
173 DEF_VEC_P(temp_slot_p);
174 DEF_VEC_ALLOC_P(temp_slot_p,gc);
175 struct ipa_opt_pass_d;
176 typedef struct ipa_opt_pass_d *ipa_opt_pass;
177
178 DEF_VEC_P(ipa_opt_pass);
179 DEF_VEC_ALLOC_P(ipa_opt_pass,heap);
180
181 struct GTY(()) varasm_status {
182 /* If we're using a per-function constant pool, this is it. */
183 struct rtx_constant_pool *pool;
184
185 /* Number of tree-constants deferred during the expansion of this
186 function. */
187 unsigned int deferred_constants;
188 };
189
190 /* Information mainlined about RTL representation of incoming arguments. */
191 struct GTY(()) incoming_args {
192 /* Number of bytes of args popped by function being compiled on its return.
193 Zero if no bytes are to be popped.
194 May affect compilation of return insn or of function epilogue. */
195 int pops_args;
196
197 /* If function's args have a fixed size, this is that size, in bytes.
198 Otherwise, it is -1.
199 May affect compilation of return insn or of function epilogue. */
200 int size;
201
202 /* # bytes the prologue should push and pretend that the caller pushed them.
203 The prologue must do this, but only if parms can be passed in
204 registers. */
205 int pretend_args_size;
206
207 /* This is the offset from the arg pointer to the place where the first
208 anonymous arg can be found, if there is one. */
209 rtx arg_offset_rtx;
210
211 /* Quantities of various kinds of registers
212 used for the current function's args. */
213 CUMULATIVE_ARGS info;
214
215 /* The arg pointer hard register, or the pseudo into which it was copied. */
216 rtx internal_arg_pointer;
217 };
218
219 /* Data for function partitioning. */
220 struct GTY(()) function_subsections {
221 /* Assembly labels for the hot and cold text sections, to
222 be used by debugger functions for determining the size of text
223 sections. */
224
225 const char *hot_section_label;
226 const char *cold_section_label;
227 const char *hot_section_end_label;
228 const char *cold_section_end_label;
229 };
230
231 /* Describe an empty area of space in the stack frame. These can be chained
232 into a list; this is used to keep track of space wasted for alignment
233 reasons. */
234 struct GTY(()) frame_space
235 {
236 struct frame_space *next;
237
238 HOST_WIDE_INT start;
239 HOST_WIDE_INT length;
240 };
241
242 /* Datastructures maintained for currently processed function in RTL form. */
243 struct GTY(()) rtl_data {
244 struct expr_status expr;
245 struct emit_status emit;
246 struct varasm_status varasm;
247 struct incoming_args args;
248 struct function_subsections subsections;
249 struct rtl_eh eh;
250
251 /* For function.c */
252
253 /* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is
254 defined, the needed space is pushed by the prologue. */
255 int outgoing_args_size;
256
257 /* If nonzero, an RTL expression for the location at which the current
258 function returns its result. If the current function returns its
259 result in a register, current_function_return_rtx will always be
260 the hard register containing the result. */
261 rtx return_rtx;
262
263 /* Opaque pointer used by get_hard_reg_initial_val and
264 has_hard_reg_initial_val (see integrate.[hc]). */
265 struct initial_value_struct *hard_reg_initial_vals;
266
267 /* A variable living at the top of the frame that holds a known value.
268 Used for detecting stack clobbers. */
269 tree stack_protect_guard;
270
271 /* List (chain of EXPR_LIST) of labels heading the current handlers for
272 nonlocal gotos. */
273 rtx x_nonlocal_goto_handler_labels;
274
275 /* Label that will go on function epilogue.
276 Jumping to this label serves as a "return" instruction
277 on machines which require execution of the epilogue on all returns. */
278 rtx x_return_label;
279
280 /* Label that will go on the end of function epilogue.
281 Jumping to this label serves as a "naked return" instruction
282 on machines which require execution of the epilogue on all returns. */
283 rtx x_naked_return_label;
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 /* List of empty areas in the stack frame. */
290 struct frame_space *frame_space_list;
291
292 /* Place after which to insert the tail_recursion_label if we need one. */
293 rtx x_stack_check_probe_note;
294
295 /* Location at which to save the argument pointer if it will need to be
296 referenced. There are two cases where this is done: if nonlocal gotos
297 exist, or if vars stored at an offset from the argument pointer will be
298 needed by inner routines. */
299 rtx x_arg_pointer_save_area;
300
301 /* Dynamic Realign Argument Pointer used for realigning stack. */
302 rtx drap_reg;
303
304 /* Offset to end of allocated area of stack frame.
305 If stack grows down, this is the address of the last stack slot allocated.
306 If stack grows up, this is the address for the next slot. */
307 HOST_WIDE_INT x_frame_offset;
308
309 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */
310 rtx x_parm_birth_insn;
311
312 /* List of all used temporaries allocated, by level. */
313 VEC(temp_slot_p,gc) *x_used_temp_slots;
314
315 /* List of available temp slots. */
316 struct temp_slot *x_avail_temp_slots;
317
318 /* Current nesting level for temporaries. */
319 int x_temp_slot_level;
320
321 /* The largest alignment needed on the stack, including requirement
322 for outgoing stack alignment. */
323 unsigned int stack_alignment_needed;
324
325 /* Preferred alignment of the end of stack frame, which is preferred
326 to call other functions. */
327 unsigned int preferred_stack_boundary;
328
329 /* The minimum alignment of parameter stack. */
330 unsigned int parm_stack_boundary;
331
332 /* The largest alignment of slot allocated on the stack. */
333 unsigned int max_used_stack_slot_alignment;
334
335 /* The stack alignment estimated before reload, with consideration of
336 following factors:
337 1. Alignment of local stack variables (max_used_stack_slot_alignment)
338 2. Alignment requirement to call other functions
339 (preferred_stack_boundary)
340 3. Alignment of non-local stack variables but might be spilled in
341 local stack. */
342 unsigned int stack_alignment_estimated;
343
344 /* For reorg. */
345
346 /* If some insns can be deferred to the delay slots of the epilogue, the
347 delay list for them is recorded here. */
348 rtx epilogue_delay_list;
349
350 /* Nonzero if function being compiled called builtin_return_addr or
351 builtin_frame_address with nonzero count. */
352 bool accesses_prior_frames;
353
354 /* Nonzero if the function calls __builtin_eh_return. */
355 bool calls_eh_return;
356
357 /* Nonzero if function saves all registers, e.g. if it has a nonlocal
358 label that can reach the exit block via non-exceptional paths. */
359 bool saves_all_registers;
360
361 /* Nonzero if function being compiled has nonlocal gotos to parent
362 function. */
363 bool has_nonlocal_goto;
364
365 /* Nonzero if function being compiled has an asm statement. */
366 bool has_asm_statement;
367
368 /* This bit is used by the exception handling logic. It is set if all
369 calls (if any) are sibling calls. Such functions do not have to
370 have EH tables generated, as they cannot throw. A call to such a
371 function, however, should be treated as throwing if any of its callees
372 can throw. */
373 bool all_throwers_are_sibcalls;
374
375 /* Nonzero if stack limit checking should be enabled in the current
376 function. */
377 bool limit_stack;
378
379 /* Nonzero if profiling code should be generated. */
380 bool profile;
381
382 /* Nonzero if the current function uses the constant pool. */
383 bool uses_const_pool;
384
385 /* Nonzero if the current function uses pic_offset_table_rtx. */
386 bool uses_pic_offset_table;
387
388 /* Nonzero if the current function needs an lsda for exception handling. */
389 bool uses_eh_lsda;
390
391 /* Set when the tail call has been produced. */
392 bool tail_call_emit;
393
394 /* Nonzero if code to initialize arg_pointer_save_area has been emitted. */
395 bool arg_pointer_save_area_init;
396
397 /* Nonzero if current function must be given a frame pointer.
398 Set in global.c if anything is allocated on the stack there. */
399 bool frame_pointer_needed;
400
401 /* When set, expand should optimize for speed. */
402 bool maybe_hot_insn_p;
403
404 /* Nonzero if function stack realignment is needed. This flag may be
405 set twice: before and after reload. It is set before reload wrt
406 stack alignment estimation before reload. It will be changed after
407 reload if by then criteria of stack realignment is different.
408 The value set after reload is the accurate one and is finalized. */
409 bool stack_realign_needed;
410
411 /* Nonzero if function stack realignment is tried. This flag is set
412 only once before reload. It affects register elimination. This
413 is used to generate DWARF debug info for stack variables. */
414 bool stack_realign_tried;
415
416 /* Nonzero if function being compiled needs dynamic realigned
417 argument pointer (drap) if stack needs realigning. */
418 bool need_drap;
419
420 /* Nonzero if function stack realignment estimation is done, namely
421 stack_realign_needed flag has been set before reload wrt estimated
422 stack alignment info. */
423 bool stack_realign_processed;
424
425 /* Nonzero if function stack realignment has been finalized, namely
426 stack_realign_needed flag has been set and finalized after reload. */
427 bool stack_realign_finalized;
428
429 /* True if dbr_schedule has already been called for this function. */
430 bool dbr_scheduled_p;
431
432 /* True if current function can not throw. Unlike
433 TREE_NOTHROW (current_function_decl) it is set even for overwritable
434 function where currently compiled version of it is nothrow. */
435 bool nothrow;
436
437 /* Like regs_ever_live, but 1 if a reg is set or clobbered from an
438 asm. Unlike regs_ever_live, elements of this array corresponding
439 to eliminable regs (like the frame pointer) are set if an asm
440 sets them. */
441 HARD_REG_SET asm_clobbers;
442 };
443
444 #define return_label (crtl->x_return_label)
445 #define naked_return_label (crtl->x_naked_return_label)
446 #define stack_slot_list (crtl->x_stack_slot_list)
447 #define parm_birth_insn (crtl->x_parm_birth_insn)
448 #define frame_offset (crtl->x_frame_offset)
449 #define stack_check_probe_note (crtl->x_stack_check_probe_note)
450 #define arg_pointer_save_area (crtl->x_arg_pointer_save_area)
451 #define used_temp_slots (crtl->x_used_temp_slots)
452 #define avail_temp_slots (crtl->x_avail_temp_slots)
453 #define temp_slot_level (crtl->x_temp_slot_level)
454 #define nonlocal_goto_handler_labels (crtl->x_nonlocal_goto_handler_labels)
455 #define frame_pointer_needed (crtl->frame_pointer_needed)
456 #define stack_realign_fp (crtl->stack_realign_needed && !crtl->need_drap)
457 #define stack_realign_drap (crtl->stack_realign_needed && crtl->need_drap)
458
459 extern GTY(()) struct rtl_data x_rtl;
460
461 /* Accessor to RTL datastructures. We keep them statically allocated now since
462 we never keep multiple functions. For threaded compiler we might however
463 want to do differently. */
464 #define crtl (&x_rtl)
465
466 struct GTY(()) stack_usage
467 {
468 /* # of bytes of static stack space allocated by the function. */
469 HOST_WIDE_INT static_stack_size;
470
471 /* # of bytes of dynamic stack space allocated by the function. This is
472 meaningful only if has_unbounded_dynamic_stack_size is zero. */
473 HOST_WIDE_INT dynamic_stack_size;
474
475 /* # of bytes of space pushed onto the stack after the prologue. If
476 !ACCUMULATE_OUTGOING_ARGS, it contains the outgoing arguments. */
477 int pushed_stack_size;
478
479 /* # of dynamic allocations in the function. */
480 unsigned int dynamic_alloc_count : 31;
481
482 /* Nonzero if the amount of stack space allocated dynamically cannot
483 be bounded at compile-time. */
484 unsigned int has_unbounded_dynamic_stack_size : 1;
485 };
486
487 #define current_function_static_stack_size (cfun->su->static_stack_size)
488 #define current_function_dynamic_stack_size (cfun->su->dynamic_stack_size)
489 #define current_function_pushed_stack_size (cfun->su->pushed_stack_size)
490 #define current_function_dynamic_alloc_count (cfun->su->dynamic_alloc_count)
491 #define current_function_has_unbounded_dynamic_stack_size \
492 (cfun->su->has_unbounded_dynamic_stack_size)
493 #define current_function_allocates_dynamic_stack_space \
494 (current_function_dynamic_stack_size != 0 \
495 || current_function_has_unbounded_dynamic_stack_size)
496
497 /* This structure can save all the important global and static variables
498 describing the status of the current function. */
499
500 struct GTY(()) function {
501 struct eh_status *eh;
502
503 /* The control flow graph for this function. */
504 struct control_flow_graph *cfg;
505
506 /* GIMPLE body for this function. */
507 struct gimple_seq_d *gimple_body;
508
509 /* SSA and dataflow information. */
510 struct gimple_df *gimple_df;
511
512 /* The loops in this function. */
513 struct loops *x_current_loops;
514
515 /* The stack usage of this function. */
516 struct stack_usage *su;
517
518 /* Value histograms attached to particular statements. */
519 htab_t GTY((skip)) value_histograms;
520
521 /* For function.c. */
522
523 /* Points to the FUNCTION_DECL of this function. */
524 tree decl;
525
526 /* A PARM_DECL that should contain the static chain for this function.
527 It will be initialized at the beginning of the function. */
528 tree static_chain_decl;
529
530 /* An expression that contains the non-local goto save area. The first
531 word is the saved frame pointer and the second is the saved stack
532 pointer. */
533 tree nonlocal_goto_save_area;
534
535 /* Vector of function local variables, functions, types and constants. */
536 VEC(tree,gc) *local_decls;
537
538 /* For md files. */
539
540 /* tm.h can use this to store whatever it likes. */
541 struct machine_function * GTY ((maybe_undef)) machine;
542
543 /* Language-specific code can use this to store whatever it likes. */
544 struct language_function * language;
545
546 /* Used types hash table. */
547 htab_t GTY ((param_is (union tree_node))) used_types_hash;
548
549 /* Last statement uid. */
550 int last_stmt_uid;
551
552 /* Function sequence number for profiling, debugging, etc. */
553 int funcdef_no;
554
555 /* Line number of the start of the function for debugging purposes. */
556 location_t function_start_locus;
557
558 /* Line number of the end of the function. */
559 location_t function_end_locus;
560
561 /* Properties used by the pass manager. */
562 unsigned int curr_properties;
563 unsigned int last_verified;
564
565 /* Non-null if the function does something that would prevent it from
566 being copied; this applies to both versioning and inlining. Set to
567 a string describing the reason for failure. */
568 const char * GTY((skip)) cannot_be_copied_reason;
569
570 /* Collected bit flags. */
571
572 /* Number of units of general registers that need saving in stdarg
573 function. What unit is depends on the backend, either it is number
574 of bytes, or it can be number of registers. */
575 unsigned int va_list_gpr_size : 8;
576
577 /* Number of units of floating point registers that need saving in stdarg
578 function. */
579 unsigned int va_list_fpr_size : 8;
580
581 /* Nonzero if function being compiled can call setjmp. */
582 unsigned int calls_setjmp : 1;
583
584 /* Nonzero if function being compiled can call alloca,
585 either as a subroutine or builtin. */
586 unsigned int calls_alloca : 1;
587
588 /* Nonzero if function being compiled receives nonlocal gotos
589 from nested functions. */
590 unsigned int has_nonlocal_label : 1;
591
592 /* Nonzero if we've set cannot_be_copied_reason. I.e. if
593 (cannot_be_copied_set && !cannot_be_copied_reason), the function
594 can in fact be copied. */
595 unsigned int cannot_be_copied_set : 1;
596
597 /* Nonzero if current function uses stdarg.h or equivalent. */
598 unsigned int stdarg : 1;
599
600 unsigned int after_inlining : 1;
601 unsigned int always_inline_functions_inlined : 1;
602
603 /* Nonzero if function being compiled can throw synchronous non-call
604 exceptions. */
605 unsigned int can_throw_non_call_exceptions : 1;
606
607 /* Fields below this point are not set for abstract functions; see
608 allocate_struct_function. */
609
610 /* Nonzero if function being compiled needs to be given an address
611 where the value should be stored. */
612 unsigned int returns_struct : 1;
613
614 /* Nonzero if function being compiled needs to
615 return the address of where it has put a structure value. */
616 unsigned int returns_pcc_struct : 1;
617
618 /* Nonzero if pass_tree_profile was run on this function. */
619 unsigned int after_tree_profile : 1;
620
621 /* Nonzero if this function has local DECL_HARD_REGISTER variables.
622 In this case code motion has to be done more carefully. */
623 unsigned int has_local_explicit_reg_vars : 1;
624
625 /* Nonzero if the current function is a thunk, i.e., a lightweight
626 function implemented by the output_mi_thunk hook) that just
627 adjusts one of its arguments and forwards to another
628 function. */
629 unsigned int is_thunk : 1;
630 };
631
632 /* Add the decl D to the local_decls list of FUN. */
633
634 static inline void
635 add_local_decl (struct function *fun, tree d)
636 {
637 VEC_safe_push (tree, gc, fun->local_decls, d);
638 }
639
640 #define FOR_EACH_LOCAL_DECL(FUN, I, D) \
641 FOR_EACH_VEC_ELT_REVERSE (tree, (FUN)->local_decls, I, D)
642
643 /* If va_list_[gf]pr_size is set to this, it means we don't know how
644 many units need to be saved. */
645 #define VA_LIST_MAX_GPR_SIZE 255
646 #define VA_LIST_MAX_FPR_SIZE 255
647
648 /* The function currently being compiled. */
649 extern GTY(()) struct function *cfun;
650
651 /* In order to ensure that cfun is not set directly, we redefine it so
652 that it is not an lvalue. Rather than assign to cfun, use
653 push_cfun or set_cfun. */
654 #define cfun (cfun + 0)
655
656 /* Nonzero if we've already converted virtual regs to hard regs. */
657 extern int virtuals_instantiated;
658
659 /* Nonzero if at least one trampoline has been created. */
660 extern int trampolines_created;
661
662 struct GTY(()) types_used_by_vars_entry {
663 tree type;
664 tree var_decl;
665 };
666
667 /* Hash table making the relationship between a global variable
668 and the types it references in its initializer. The key of the
669 entry is a referenced type, and the value is the DECL of the global
670 variable. types_use_by_vars_do_hash and types_used_by_vars_eq below are
671 the hash and equality functions to use for this hash table. */
672 extern GTY((param_is (struct types_used_by_vars_entry))) htab_t
673 types_used_by_vars_hash;
674
675 hashval_t types_used_by_vars_do_hash (const void*);
676 int types_used_by_vars_eq (const void *, const void *);
677 void types_used_by_var_decl_insert (tree type, tree var_decl);
678
679 /* During parsing of a global variable, this vector contains the types
680 referenced by the global variable. */
681 extern GTY(()) VEC(tree,gc) *types_used_by_cur_var_decl;
682
683
684 /* cfun shouldn't be set directly; use one of these functions instead. */
685 extern void set_cfun (struct function *new_cfun);
686 extern void push_cfun (struct function *new_cfun);
687 extern void pop_cfun (void);
688 extern void instantiate_decl_rtl (rtx x);
689
690 /* For backward compatibility... eventually these should all go away. */
691 #define current_function_funcdef_no (cfun->funcdef_no)
692
693 #define current_loops (cfun->x_current_loops)
694 #define dom_computed (cfun->cfg->x_dom_computed)
695 #define n_bbs_in_dom_tree (cfun->cfg->x_n_bbs_in_dom_tree)
696 #define VALUE_HISTOGRAMS(fun) (fun)->value_histograms
697
698 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
699 and create duplicate blocks. */
700 extern void reorder_blocks (void);
701
702 /* Set BLOCK_NUMBER for all the blocks in FN. */
703 extern void number_blocks (tree);
704
705 extern void clear_block_marks (tree);
706 extern tree blocks_nreverse (tree);
707 extern tree block_chainon (tree, tree);
708
709 /* Return size needed for stack frame based on slots so far allocated.
710 This size counts from zero. It is not rounded to STACK_BOUNDARY;
711 the caller may have to do that. */
712 extern HOST_WIDE_INT get_frame_size (void);
713
714 /* Issue an error message and return TRUE if frame OFFSET overflows in
715 the signed target pointer arithmetics for function FUNC. Otherwise
716 return FALSE. */
717 extern bool frame_offset_overflow (HOST_WIDE_INT, tree);
718
719 /* A pointer to a function to create target specific, per-function
720 data structures. */
721 extern struct machine_function * (*init_machine_status) (void);
722
723 /* Save and restore status information for a nested function. */
724 extern void free_after_parsing (struct function *);
725 extern void free_after_compilation (struct function *);
726
727 extern void init_varasm_status (void);
728
729 #ifdef RTX_CODE
730 extern void diddle_return_value (void (*)(rtx, void*), void*);
731 extern void clobber_return_register (void);
732 #endif
733
734 extern rtx get_arg_pointer_save_area (void);
735
736 /* Returns the name of the current function. */
737 extern const char *current_function_name (void);
738
739 extern void do_warn_unused_parameter (tree);
740
741 extern bool pass_by_reference (CUMULATIVE_ARGS *, enum machine_mode,
742 tree, bool);
743 extern bool reference_callee_copied (CUMULATIVE_ARGS *, enum machine_mode,
744 tree, bool);
745
746 extern void used_types_insert (tree);
747
748 extern int get_next_funcdef_no (void);
749 extern int get_last_funcdef_no (void);
750
751 /* In predict.c */
752 extern bool optimize_function_for_size_p (struct function *);
753 extern bool optimize_function_for_speed_p (struct function *);
754
755 #endif /* GCC_FUNCTION_H */