]> git.ipfire.org Git - thirdparty/gcc.git/blob - gcc/function.h
81d76bf55e83ae252322672b15735be1eee4968a
[thirdparty/gcc.git] / gcc / function.h
1 /* Structure for saving state for a nested function.
2 Copyright (C) 1989-2015 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20 #ifndef GCC_FUNCTION_H
21 #define GCC_FUNCTION_H
22
23
24 /* Stack of pending (incomplete) sequences saved by `start_sequence'.
25 Each element describes one pending sequence.
26 The main insn-chain is saved in the last element of the chain,
27 unless the chain is empty. */
28
29 struct GTY(()) sequence_stack {
30 /* First and last insns in the chain of the saved sequence. */
31 rtx_insn *first;
32 rtx_insn *last;
33 struct sequence_stack *next;
34 };
35 \f
36 struct GTY(()) emit_status {
37 /* This is reset to LAST_VIRTUAL_REGISTER + 1 at the start of each function.
38 After rtl generation, it is 1 plus the largest register number used. */
39 int x_reg_rtx_no;
40
41 /* Lowest label number in current function. */
42 int x_first_label_num;
43
44 /* seq.first and seq.last are the ends of the doubly-linked chain of
45 rtl for the current function. Both are reset to null at the
46 start of rtl generation for the function.
47
48 start_sequence saves both of these on seq.next and then starts
49 a new, nested sequence of insns.
50
51 seq.next is a stack of pending (incomplete) sequences saved by
52 start_sequence. Each element describes one pending sequence.
53 The main insn-chain is the last element of the chain. */
54 struct sequence_stack seq;
55
56 /* INSN_UID for next insn emitted.
57 Reset to 1 for each function compiled. */
58 int x_cur_insn_uid;
59
60 /* INSN_UID for next debug insn emitted. Only used if
61 --param min-nondebug-insn-uid=<value> is given with nonzero value. */
62 int x_cur_debug_insn_uid;
63
64 /* The length of the regno_pointer_align, regno_decl, and x_regno_reg_rtx
65 vectors. Since these vectors are needed during the expansion phase when
66 the total number of registers in the function is not yet known, the
67 vectors are copied and made bigger when necessary. */
68 int regno_pointer_align_length;
69
70 /* Indexed by pseudo register number, if nonzero gives the known alignment
71 for that pseudo (if REG_POINTER is set in x_regno_reg_rtx).
72 Allocated in parallel with x_regno_reg_rtx. */
73 unsigned char * GTY((skip)) regno_pointer_align;
74 };
75
76
77 /* Indexed by register number, gives an rtx for that register (and only
78 that register). For pseudo registers, it is the unique rtx for
79 that pseudo. For hard registers, it is an rtx of the mode specified
80 by reg_raw_mode.
81
82 FIXME: We could put it into emit_status struct, but gengtype is not
83 able to deal with length attribute nested in top level structures. */
84
85 extern GTY ((length ("crtl->emit.x_reg_rtx_no"))) rtx * regno_reg_rtx;
86
87 /* For backward compatibility... eventually these should all go away. */
88 #define reg_rtx_no (crtl->emit.x_reg_rtx_no)
89
90 #define REGNO_POINTER_ALIGN(REGNO) (crtl->emit.regno_pointer_align[REGNO])
91
92 struct GTY(()) expr_status {
93 /* Number of units that we should eventually pop off the stack.
94 These are the arguments to function calls that have already returned. */
95 int x_pending_stack_adjust;
96
97 /* Under some ABIs, it is the caller's responsibility to pop arguments
98 pushed for function calls. A naive implementation would simply pop
99 the arguments immediately after each call. However, if several
100 function calls are made in a row, it is typically cheaper to pop
101 all the arguments after all of the calls are complete since a
102 single pop instruction can be used. Therefore, GCC attempts to
103 defer popping the arguments until absolutely necessary. (For
104 example, at the end of a conditional, the arguments must be popped,
105 since code outside the conditional won't know whether or not the
106 arguments need to be popped.)
107
108 When INHIBIT_DEFER_POP is nonzero, however, the compiler does not
109 attempt to defer pops. Instead, the stack is popped immediately
110 after each call. Rather then setting this variable directly, use
111 NO_DEFER_POP and OK_DEFER_POP. */
112 int x_inhibit_defer_pop;
113
114 /* If PREFERRED_STACK_BOUNDARY and PUSH_ROUNDING are defined, the stack
115 boundary can be momentarily unaligned while pushing the arguments.
116 Record the delta since last aligned boundary here in order to get
117 stack alignment in the nested function calls working right. */
118 int x_stack_pointer_delta;
119
120 /* Nonzero means __builtin_saveregs has already been done in this function.
121 The value is the pseudoreg containing the value __builtin_saveregs
122 returned. */
123 rtx x_saveregs_value;
124
125 /* Similarly for __builtin_apply_args. */
126 rtx x_apply_args_value;
127
128 /* List of labels that must never be deleted. */
129 rtx_insn_list *x_forced_labels;
130 };
131
132 typedef struct call_site_record_d *call_site_record;
133
134 /* RTL representation of exception handling. */
135 struct GTY(()) rtl_eh {
136 rtx ehr_stackadj;
137 rtx ehr_handler;
138 rtx_code_label *ehr_label;
139
140 rtx sjlj_fc;
141 rtx_insn *sjlj_exit_after;
142
143 vec<uchar, va_gc> *action_record_data;
144
145 vec<call_site_record, va_gc> *call_site_record_v[2];
146 };
147
148 #define pending_stack_adjust (crtl->expr.x_pending_stack_adjust)
149 #define inhibit_defer_pop (crtl->expr.x_inhibit_defer_pop)
150 #define saveregs_value (crtl->expr.x_saveregs_value)
151 #define apply_args_value (crtl->expr.x_apply_args_value)
152 #define forced_labels (crtl->expr.x_forced_labels)
153 #define stack_pointer_delta (crtl->expr.x_stack_pointer_delta)
154
155 struct gimple_df;
156 struct temp_slot;
157 typedef struct temp_slot *temp_slot_p;
158 struct call_site_record_d;
159 struct dw_fde_node;
160
161 class ipa_opt_pass_d;
162 typedef ipa_opt_pass_d *ipa_opt_pass;
163
164
165 struct GTY(()) varasm_status {
166 /* If we're using a per-function constant pool, this is it. */
167 struct rtx_constant_pool *pool;
168
169 /* Number of tree-constants deferred during the expansion of this
170 function. */
171 unsigned int deferred_constants;
172 };
173
174 /* Information mainlined about RTL representation of incoming arguments. */
175 struct GTY(()) incoming_args {
176 /* Number of bytes of args popped by function being compiled on its return.
177 Zero if no bytes are to be popped.
178 May affect compilation of return insn or of function epilogue. */
179 int pops_args;
180
181 /* If function's args have a fixed size, this is that size, in bytes.
182 Otherwise, it is -1.
183 May affect compilation of return insn or of function epilogue. */
184 int size;
185
186 /* # bytes the prologue should push and pretend that the caller pushed them.
187 The prologue must do this, but only if parms can be passed in
188 registers. */
189 int pretend_args_size;
190
191 /* This is the offset from the arg pointer to the place where the first
192 anonymous arg can be found, if there is one. */
193 rtx arg_offset_rtx;
194
195 /* Quantities of various kinds of registers
196 used for the current function's args. */
197 CUMULATIVE_ARGS info;
198
199 /* The arg pointer hard register, or the pseudo into which it was copied. */
200 rtx internal_arg_pointer;
201 };
202
203 /* Data for function partitioning. */
204 struct GTY(()) function_subsections {
205 /* Assembly labels for the hot and cold text sections, to
206 be used by debugger functions for determining the size of text
207 sections. */
208
209 const char *hot_section_label;
210 const char *cold_section_label;
211 const char *hot_section_end_label;
212 const char *cold_section_end_label;
213 };
214
215 /* Describe an empty area of space in the stack frame. These can be chained
216 into a list; this is used to keep track of space wasted for alignment
217 reasons. */
218 struct GTY(()) frame_space
219 {
220 struct frame_space *next;
221
222 HOST_WIDE_INT start;
223 HOST_WIDE_INT length;
224 };
225
226 /* Datastructures maintained for currently processed function in RTL form. */
227 struct GTY(()) rtl_data {
228 struct expr_status expr;
229 struct emit_status emit;
230 struct varasm_status varasm;
231 struct incoming_args args;
232 struct function_subsections subsections;
233 struct rtl_eh eh;
234
235 /* For function.c */
236
237 /* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is
238 defined, the needed space is pushed by the prologue. */
239 int outgoing_args_size;
240
241 /* If nonzero, an RTL expression for the location at which the current
242 function returns its result. If the current function returns its
243 result in a register, current_function_return_rtx will always be
244 the hard register containing the result. */
245 rtx return_rtx;
246 /* If nonxero, an RTL expression for the lcoation at which the current
247 function returns bounds for its result. */
248 rtx return_bnd;
249
250 /* Vector of initial-value pairs. Each pair consists of a pseudo
251 register of approprite mode that stores the initial value a hard
252 register REGNO, and that hard register itself. */
253 /* ??? This could be a VEC but there is currently no way to define an
254 opaque VEC type. */
255 struct initial_value_struct *hard_reg_initial_vals;
256
257 /* A variable living at the top of the frame that holds a known value.
258 Used for detecting stack clobbers. */
259 tree stack_protect_guard;
260
261 /* List (chain of INSN_LIST) of labels heading the current handlers for
262 nonlocal gotos. */
263 rtx_insn_list *x_nonlocal_goto_handler_labels;
264
265 /* Label that will go on function epilogue.
266 Jumping to this label serves as a "return" instruction
267 on machines which require execution of the epilogue on all returns. */
268 rtx_code_label *x_return_label;
269
270 /* Label that will go on the end of function epilogue.
271 Jumping to this label serves as a "naked return" instruction
272 on machines which require execution of the epilogue on all returns. */
273 rtx_code_label *x_naked_return_label;
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_expr_list *x_stack_slot_list;
278
279 /* List of empty areas in the stack frame. */
280 struct frame_space *frame_space_list;
281
282 /* Place after which to insert the tail_recursion_label if we need one. */
283 rtx_note *x_stack_check_probe_note;
284
285 /* Location at which to save the argument pointer if it will need to be
286 referenced. There are two cases where this is done: if nonlocal gotos
287 exist, or if vars stored at an offset from the argument pointer will be
288 needed by inner routines. */
289 rtx x_arg_pointer_save_area;
290
291 /* Dynamic Realign Argument Pointer used for realigning stack. */
292 rtx drap_reg;
293
294 /* Offset to end of allocated area of stack frame.
295 If stack grows down, this is the address of the last stack slot allocated.
296 If stack grows up, this is the address for the next slot. */
297 HOST_WIDE_INT x_frame_offset;
298
299 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */
300 rtx_insn *x_parm_birth_insn;
301
302 /* List of all used temporaries allocated, by level. */
303 vec<temp_slot_p, va_gc> *x_used_temp_slots;
304
305 /* List of available temp slots. */
306 struct temp_slot *x_avail_temp_slots;
307
308 /* Current nesting level for temporaries. */
309 int x_temp_slot_level;
310
311 /* The largest alignment needed on the stack, including requirement
312 for outgoing stack alignment. */
313 unsigned int stack_alignment_needed;
314
315 /* Preferred alignment of the end of stack frame, which is preferred
316 to call other functions. */
317 unsigned int preferred_stack_boundary;
318
319 /* The minimum alignment of parameter stack. */
320 unsigned int parm_stack_boundary;
321
322 /* The largest alignment of slot allocated on the stack. */
323 unsigned int max_used_stack_slot_alignment;
324
325 /* The stack alignment estimated before reload, with consideration of
326 following factors:
327 1. Alignment of local stack variables (max_used_stack_slot_alignment)
328 2. Alignment requirement to call other functions
329 (preferred_stack_boundary)
330 3. Alignment of non-local stack variables but might be spilled in
331 local stack. */
332 unsigned int stack_alignment_estimated;
333
334 /* For reorg. */
335
336 /* Nonzero if function being compiled called builtin_return_addr or
337 builtin_frame_address with nonzero count. */
338 bool accesses_prior_frames;
339
340 /* Nonzero if the function calls __builtin_eh_return. */
341 bool calls_eh_return;
342
343 /* Nonzero if function saves all registers, e.g. if it has a nonlocal
344 label that can reach the exit block via non-exceptional paths. */
345 bool saves_all_registers;
346
347 /* Nonzero if function being compiled has nonlocal gotos to parent
348 function. */
349 bool has_nonlocal_goto;
350
351 /* Nonzero if function being compiled has an asm statement. */
352 bool has_asm_statement;
353
354 /* This bit is used by the exception handling logic. It is set if all
355 calls (if any) are sibling calls. Such functions do not have to
356 have EH tables generated, as they cannot throw. A call to such a
357 function, however, should be treated as throwing if any of its callees
358 can throw. */
359 bool all_throwers_are_sibcalls;
360
361 /* Nonzero if stack limit checking should be enabled in the current
362 function. */
363 bool limit_stack;
364
365 /* Nonzero if profiling code should be generated. */
366 bool profile;
367
368 /* Nonzero if the current function uses the constant pool. */
369 bool uses_const_pool;
370
371 /* Nonzero if the current function uses pic_offset_table_rtx. */
372 bool uses_pic_offset_table;
373
374 /* Nonzero if the current function needs an lsda for exception handling. */
375 bool uses_eh_lsda;
376
377 /* Set when the tail call has been produced. */
378 bool tail_call_emit;
379
380 /* Nonzero if code to initialize arg_pointer_save_area has been emitted. */
381 bool arg_pointer_save_area_init;
382
383 /* Nonzero if current function must be given a frame pointer.
384 Set in reload1.c or lra-eliminations.c if anything is allocated
385 on the stack there. */
386 bool frame_pointer_needed;
387
388 /* When set, expand should optimize for speed. */
389 bool maybe_hot_insn_p;
390
391 /* Nonzero if function stack realignment is needed. This flag may be
392 set twice: before and after reload. It is set before reload wrt
393 stack alignment estimation before reload. It will be changed after
394 reload if by then criteria of stack realignment is different.
395 The value set after reload is the accurate one and is finalized. */
396 bool stack_realign_needed;
397
398 /* Nonzero if function stack realignment is tried. This flag is set
399 only once before reload. It affects register elimination. This
400 is used to generate DWARF debug info for stack variables. */
401 bool stack_realign_tried;
402
403 /* Nonzero if function being compiled needs dynamic realigned
404 argument pointer (drap) if stack needs realigning. */
405 bool need_drap;
406
407 /* Nonzero if function stack realignment estimation is done, namely
408 stack_realign_needed flag has been set before reload wrt estimated
409 stack alignment info. */
410 bool stack_realign_processed;
411
412 /* Nonzero if function stack realignment has been finalized, namely
413 stack_realign_needed flag has been set and finalized after reload. */
414 bool stack_realign_finalized;
415
416 /* True if dbr_schedule has already been called for this function. */
417 bool dbr_scheduled_p;
418
419 /* True if current function can not throw. Unlike
420 TREE_NOTHROW (current_function_decl) it is set even for overwritable
421 function where currently compiled version of it is nothrow. */
422 bool nothrow;
423
424 /* True if we performed shrink-wrapping for the current function. */
425 bool shrink_wrapped;
426
427 /* Nonzero if function being compiled doesn't modify the stack pointer
428 (ignoring the prologue and epilogue). This is only valid after
429 pass_stack_ptr_mod has run. */
430 bool sp_is_unchanging;
431
432 /* Nonzero if function being compiled doesn't contain any calls
433 (ignoring the prologue and epilogue). This is set prior to
434 local register allocation and is valid for the remaining
435 compiler passes. */
436 bool is_leaf;
437
438 /* Nonzero if the function being compiled is a leaf function which only
439 uses leaf registers. This is valid after reload (specifically after
440 sched2) and is useful only if the port defines LEAF_REGISTERS. */
441 bool uses_only_leaf_regs;
442
443 /* Nonzero if the function being compiled has undergone hot/cold partitioning
444 (under flag_reorder_blocks_and_partition) and has at least one cold
445 block. */
446 bool has_bb_partition;
447
448 /* Nonzero if the function being compiled has completed the bb reordering
449 pass. */
450 bool bb_reorder_complete;
451
452 /* Like regs_ever_live, but 1 if a reg is set or clobbered from an
453 asm. Unlike regs_ever_live, elements of this array corresponding
454 to eliminable regs (like the frame pointer) are set if an asm
455 sets them. */
456 HARD_REG_SET asm_clobbers;
457 };
458
459 #define return_label (crtl->x_return_label)
460 #define naked_return_label (crtl->x_naked_return_label)
461 #define stack_slot_list (crtl->x_stack_slot_list)
462 #define parm_birth_insn (crtl->x_parm_birth_insn)
463 #define frame_offset (crtl->x_frame_offset)
464 #define stack_check_probe_note (crtl->x_stack_check_probe_note)
465 #define arg_pointer_save_area (crtl->x_arg_pointer_save_area)
466 #define used_temp_slots (crtl->x_used_temp_slots)
467 #define avail_temp_slots (crtl->x_avail_temp_slots)
468 #define temp_slot_level (crtl->x_temp_slot_level)
469 #define nonlocal_goto_handler_labels (crtl->x_nonlocal_goto_handler_labels)
470 #define frame_pointer_needed (crtl->frame_pointer_needed)
471 #define stack_realign_fp (crtl->stack_realign_needed && !crtl->need_drap)
472 #define stack_realign_drap (crtl->stack_realign_needed && crtl->need_drap)
473
474 extern GTY(()) struct rtl_data x_rtl;
475
476 /* Accessor to RTL datastructures. We keep them statically allocated now since
477 we never keep multiple functions. For threaded compiler we might however
478 want to do differently. */
479 #define crtl (&x_rtl)
480
481 struct GTY(()) stack_usage
482 {
483 /* # of bytes of static stack space allocated by the function. */
484 HOST_WIDE_INT static_stack_size;
485
486 /* # of bytes of dynamic stack space allocated by the function. This is
487 meaningful only if has_unbounded_dynamic_stack_size is zero. */
488 HOST_WIDE_INT dynamic_stack_size;
489
490 /* # of bytes of space pushed onto the stack after the prologue. If
491 !ACCUMULATE_OUTGOING_ARGS, it contains the outgoing arguments. */
492 int pushed_stack_size;
493
494 /* Nonzero if the amount of stack space allocated dynamically cannot
495 be bounded at compile-time. */
496 unsigned int has_unbounded_dynamic_stack_size : 1;
497 };
498
499 #define current_function_static_stack_size (cfun->su->static_stack_size)
500 #define current_function_dynamic_stack_size (cfun->su->dynamic_stack_size)
501 #define current_function_pushed_stack_size (cfun->su->pushed_stack_size)
502 #define current_function_has_unbounded_dynamic_stack_size \
503 (cfun->su->has_unbounded_dynamic_stack_size)
504 #define current_function_allocates_dynamic_stack_space \
505 (current_function_dynamic_stack_size != 0 \
506 || current_function_has_unbounded_dynamic_stack_size)
507
508 /* This structure can save all the important global and static variables
509 describing the status of the current function. */
510
511 struct GTY(()) function {
512 struct eh_status *eh;
513
514 /* The control flow graph for this function. */
515 struct control_flow_graph *cfg;
516
517 /* GIMPLE body for this function. */
518 gimple_seq gimple_body;
519
520 /* SSA and dataflow information. */
521 struct gimple_df *gimple_df;
522
523 /* The loops in this function. */
524 struct loops *x_current_loops;
525
526 /* The stack usage of this function. */
527 struct stack_usage *su;
528
529 /* Value histograms attached to particular statements. */
530 htab_t GTY((skip)) value_histograms;
531
532 /* For function.c. */
533
534 /* Points to the FUNCTION_DECL of this function. */
535 tree decl;
536
537 /* A PARM_DECL that should contain the static chain for this function.
538 It will be initialized at the beginning of the function. */
539 tree static_chain_decl;
540
541 /* An expression that contains the non-local goto save area. The first
542 word is the saved frame pointer and the second is the saved stack
543 pointer. */
544 tree nonlocal_goto_save_area;
545
546 /* Vector of function local variables, functions, types and constants. */
547 vec<tree, va_gc> *local_decls;
548
549 /* In a Cilk function, the VAR_DECL for the frame descriptor. */
550 tree cilk_frame_decl;
551
552 /* For md files. */
553
554 /* tm.h can use this to store whatever it likes. */
555 struct machine_function * GTY ((maybe_undef)) machine;
556
557 /* Language-specific code can use this to store whatever it likes. */
558 struct language_function * language;
559
560 /* Used types hash table. */
561 hash_set<tree> *GTY (()) used_types_hash;
562
563 /* Dwarf2 Frame Description Entry, containing the Call Frame Instructions
564 used for unwinding. Only set when either dwarf2 unwinding or dwarf2
565 debugging is enabled. */
566 struct dw_fde_node *fde;
567
568 /* Last statement uid. */
569 int last_stmt_uid;
570
571 /* Function sequence number for profiling, debugging, etc. */
572 int funcdef_no;
573
574 /* Line number of the start of the function for debugging purposes. */
575 location_t function_start_locus;
576
577 /* Line number of the end of the function. */
578 location_t function_end_locus;
579
580 /* Properties used by the pass manager. */
581 unsigned int curr_properties;
582 unsigned int last_verified;
583
584 /* Non-null if the function does something that would prevent it from
585 being copied; this applies to both versioning and inlining. Set to
586 a string describing the reason for failure. */
587 const char * GTY((skip)) cannot_be_copied_reason;
588
589 /* Last assigned dependence info clique. */
590 unsigned short last_clique;
591
592 /* Collected bit flags. */
593
594 /* Number of units of general registers that need saving in stdarg
595 function. What unit is depends on the backend, either it is number
596 of bytes, or it can be number of registers. */
597 unsigned int va_list_gpr_size : 8;
598
599 /* Number of units of floating point registers that need saving in stdarg
600 function. */
601 unsigned int va_list_fpr_size : 8;
602
603 /* Nonzero if function being compiled can call setjmp. */
604 unsigned int calls_setjmp : 1;
605
606 /* Nonzero if function being compiled can call alloca,
607 either as a subroutine or builtin. */
608 unsigned int calls_alloca : 1;
609
610 /* This will indicate whether a function is a cilk function */
611 unsigned int is_cilk_function : 1;
612
613 /* Nonzero if this is a Cilk function that spawns. */
614 unsigned int calls_cilk_spawn : 1;
615
616 /* Nonzero if function being compiled receives nonlocal gotos
617 from nested functions. */
618 unsigned int has_nonlocal_label : 1;
619
620 /* Nonzero if we've set cannot_be_copied_reason. I.e. if
621 (cannot_be_copied_set && !cannot_be_copied_reason), the function
622 can in fact be copied. */
623 unsigned int cannot_be_copied_set : 1;
624
625 /* Nonzero if current function uses stdarg.h or equivalent. */
626 unsigned int stdarg : 1;
627
628 unsigned int after_inlining : 1;
629 unsigned int always_inline_functions_inlined : 1;
630
631 /* Nonzero if function being compiled can throw synchronous non-call
632 exceptions. */
633 unsigned int can_throw_non_call_exceptions : 1;
634
635 /* Nonzero if instructions that may throw exceptions but don't otherwise
636 contribute to the execution of the program can be deleted. */
637 unsigned int can_delete_dead_exceptions : 1;
638
639 /* Fields below this point are not set for abstract functions; see
640 allocate_struct_function. */
641
642 /* Nonzero if function being compiled needs to be given an address
643 where the value should be stored. */
644 unsigned int returns_struct : 1;
645
646 /* Nonzero if function being compiled needs to
647 return the address of where it has put a structure value. */
648 unsigned int returns_pcc_struct : 1;
649
650 /* Nonzero if this function has local DECL_HARD_REGISTER variables.
651 In this case code motion has to be done more carefully. */
652 unsigned int has_local_explicit_reg_vars : 1;
653
654 /* Nonzero if the current function is a thunk, i.e., a lightweight
655 function implemented by the output_mi_thunk hook) that just
656 adjusts one of its arguments and forwards to another
657 function. */
658 unsigned int is_thunk : 1;
659
660 /* Nonzero if the current function contains any loops with
661 loop->force_vectorize set. */
662 unsigned int has_force_vectorize_loops : 1;
663
664 /* Nonzero if the current function contains any loops with
665 nonzero value in loop->simduid. */
666 unsigned int has_simduid_loops : 1;
667
668 /* Set when the tail call has been identified. */
669 unsigned int tail_call_marked : 1;
670 };
671
672 /* Add the decl D to the local_decls list of FUN. */
673
674 void add_local_decl (struct function *fun, tree d);
675
676 #define FOR_EACH_LOCAL_DECL(FUN, I, D) \
677 FOR_EACH_VEC_SAFE_ELT_REVERSE ((FUN)->local_decls, I, D)
678
679 /* If va_list_[gf]pr_size is set to this, it means we don't know how
680 many units need to be saved. */
681 #define VA_LIST_MAX_GPR_SIZE 255
682 #define VA_LIST_MAX_FPR_SIZE 255
683
684 /* The function currently being compiled. */
685 extern GTY(()) struct function *cfun;
686
687 /* In order to ensure that cfun is not set directly, we redefine it so
688 that it is not an lvalue. Rather than assign to cfun, use
689 push_cfun or set_cfun. */
690 #define cfun (cfun + 0)
691
692 /* Nonzero if we've already converted virtual regs to hard regs. */
693 extern int virtuals_instantiated;
694
695 /* Nonzero if at least one trampoline has been created. */
696 extern int trampolines_created;
697
698 struct GTY((for_user)) types_used_by_vars_entry {
699 tree type;
700 tree var_decl;
701 };
702
703 struct used_type_hasher : ggc_hasher<types_used_by_vars_entry *>
704 {
705 static hashval_t hash (types_used_by_vars_entry *);
706 static bool equal (types_used_by_vars_entry *, types_used_by_vars_entry *);
707 };
708
709 /* Hash table making the relationship between a global variable
710 and the types it references in its initializer. The key of the
711 entry is a referenced type, and the value is the DECL of the global
712 variable. types_use_by_vars_do_hash and types_used_by_vars_eq below are
713 the hash and equality functions to use for this hash table. */
714 extern GTY(()) hash_table<used_type_hasher> *types_used_by_vars_hash;
715
716 void types_used_by_var_decl_insert (tree type, tree var_decl);
717
718 /* During parsing of a global variable, this vector contains the types
719 referenced by the global variable. */
720 extern GTY(()) vec<tree, va_gc> *types_used_by_cur_var_decl;
721
722
723 /* Return the loop tree of FN. */
724
725 inline struct loops *
726 loops_for_fn (struct function *fn)
727 {
728 return fn->x_current_loops;
729 }
730
731 /* Set the loop tree of FN to LOOPS. */
732
733 inline void
734 set_loops_for_fn (struct function *fn, struct loops *loops)
735 {
736 gcc_checking_assert (fn->x_current_loops == NULL || loops == NULL);
737 fn->x_current_loops = loops;
738 }
739
740 /* For backward compatibility... eventually these should all go away. */
741 #define current_function_funcdef_no (cfun->funcdef_no)
742
743 #define current_loops (cfun->x_current_loops)
744 #define dom_computed (cfun->cfg->x_dom_computed)
745 #define n_bbs_in_dom_tree (cfun->cfg->x_n_bbs_in_dom_tree)
746 #define VALUE_HISTOGRAMS(fun) (fun)->value_histograms
747
748 /* A pointer to a function to create target specific, per-function
749 data structures. */
750 extern struct machine_function * (*init_machine_status) (void);
751
752 enum direction {none, upward, downward};
753
754 /* Structure to record the size of a sequence of arguments
755 as the sum of a tree-expression and a constant. This structure is
756 also used to store offsets from the stack, which might be negative,
757 so the variable part must be ssizetype, not sizetype. */
758
759 struct args_size
760 {
761 HOST_WIDE_INT constant;
762 tree var;
763 };
764
765 /* Package up various arg related fields of struct args for
766 locate_and_pad_parm. */
767 struct locate_and_pad_arg_data
768 {
769 /* Size of this argument on the stack, rounded up for any padding it
770 gets. If REG_PARM_STACK_SPACE is defined, then register parms are
771 counted here, otherwise they aren't. */
772 struct args_size size;
773 /* Offset of this argument from beginning of stack-args. */
774 struct args_size offset;
775 /* Offset to the start of the stack slot. Different from OFFSET
776 if this arg pads downward. */
777 struct args_size slot_offset;
778 /* The amount that the stack pointer needs to be adjusted to
779 force alignment for the next argument. */
780 struct args_size alignment_pad;
781 /* Which way we should pad this arg. */
782 enum direction where_pad;
783 /* slot_offset is at least this aligned. */
784 unsigned int boundary;
785 };
786
787 /* Add the value of the tree INC to the `struct args_size' TO. */
788
789 #define ADD_PARM_SIZE(TO, INC) \
790 do { \
791 tree inc = (INC); \
792 if (tree_fits_shwi_p (inc)) \
793 (TO).constant += tree_to_shwi (inc); \
794 else if ((TO).var == 0) \
795 (TO).var = fold_convert (ssizetype, inc); \
796 else \
797 (TO).var = size_binop (PLUS_EXPR, (TO).var, \
798 fold_convert (ssizetype, inc)); \
799 } while (0)
800
801 #define SUB_PARM_SIZE(TO, DEC) \
802 do { \
803 tree dec = (DEC); \
804 if (tree_fits_shwi_p (dec)) \
805 (TO).constant -= tree_to_shwi (dec); \
806 else if ((TO).var == 0) \
807 (TO).var = size_binop (MINUS_EXPR, ssize_int (0), \
808 fold_convert (ssizetype, dec)); \
809 else \
810 (TO).var = size_binop (MINUS_EXPR, (TO).var, \
811 fold_convert (ssizetype, dec)); \
812 } while (0)
813
814 /* Convert the implicit sum in a `struct args_size' into a tree
815 of type ssizetype. */
816 #define ARGS_SIZE_TREE(SIZE) \
817 ((SIZE).var == 0 ? ssize_int ((SIZE).constant) \
818 : size_binop (PLUS_EXPR, fold_convert (ssizetype, (SIZE).var), \
819 ssize_int ((SIZE).constant)))
820
821 /* Convert the implicit sum in a `struct args_size' into an rtx. */
822 #define ARGS_SIZE_RTX(SIZE) \
823 ((SIZE).var == 0 ? GEN_INT ((SIZE).constant) \
824 : expand_normal (ARGS_SIZE_TREE (SIZE)))
825
826 #define ASLK_REDUCE_ALIGN 1
827 #define ASLK_RECORD_PAD 2
828
829 \f
830
831 extern void push_function_context (void);
832 extern void pop_function_context (void);
833
834 /* Save and restore status information for a nested function. */
835 extern void free_after_parsing (struct function *);
836 extern void free_after_compilation (struct function *);
837
838 /* Return size needed for stack frame based on slots so far allocated.
839 This size counts from zero. It is not rounded to STACK_BOUNDARY;
840 the caller may have to do that. */
841 extern HOST_WIDE_INT get_frame_size (void);
842
843 /* Issue an error message and return TRUE if frame OFFSET overflows in
844 the signed target pointer arithmetics for function FUNC. Otherwise
845 return FALSE. */
846 extern bool frame_offset_overflow (HOST_WIDE_INT, tree);
847
848 extern rtx assign_stack_local_1 (machine_mode, HOST_WIDE_INT, int, int);
849 extern rtx assign_stack_local (machine_mode, HOST_WIDE_INT, int);
850 extern rtx assign_stack_temp_for_type (machine_mode, HOST_WIDE_INT, tree);
851 extern rtx assign_stack_temp (machine_mode, HOST_WIDE_INT);
852 extern rtx assign_temp (tree, int, int);
853 extern void update_temp_slot_address (rtx, rtx);
854 extern void preserve_temp_slots (rtx);
855 extern void free_temp_slots (void);
856 extern void push_temp_slots (void);
857 extern void pop_temp_slots (void);
858 extern void init_temp_slots (void);
859 extern rtx get_hard_reg_initial_reg (rtx);
860 extern rtx get_hard_reg_initial_val (machine_mode, unsigned int);
861 extern rtx has_hard_reg_initial_val (machine_mode, unsigned int);
862
863 /* Called from gimple_expand_cfg. */
864 extern unsigned int emit_initial_value_sets (void);
865
866 extern bool initial_value_entry (int i, rtx *, rtx *);
867 extern void instantiate_decl_rtl (rtx x);
868 extern int aggregate_value_p (const_tree, const_tree);
869 extern bool use_register_for_decl (const_tree);
870 extern bool pass_by_reference (CUMULATIVE_ARGS *, machine_mode,
871 tree, bool);
872 extern bool reference_callee_copied (CUMULATIVE_ARGS *, machine_mode,
873 tree, bool);
874 extern gimple_seq gimplify_parameters (void);
875 extern void locate_and_pad_parm (machine_mode, tree, int, int, int,
876 tree, struct args_size *,
877 struct locate_and_pad_arg_data *);
878 extern void generate_setjmp_warnings (void);
879
880 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
881 and create duplicate blocks. */
882 extern void reorder_blocks (void);
883 extern void clear_block_marks (tree);
884 extern tree blocks_nreverse (tree);
885 extern tree block_chainon (tree, tree);
886
887 /* Set BLOCK_NUMBER for all the blocks in FN. */
888 extern void number_blocks (tree);
889
890 /* cfun shouldn't be set directly; use one of these functions instead. */
891 extern void set_cfun (struct function *new_cfun);
892 extern void push_cfun (struct function *new_cfun);
893 extern void pop_cfun (void);
894
895 extern int get_next_funcdef_no (void);
896 extern int get_last_funcdef_no (void);
897 extern void allocate_struct_function (tree, bool);
898 extern void push_struct_function (tree fndecl);
899 extern void push_dummy_function (bool);
900 extern void pop_dummy_function (void);
901 extern void init_dummy_function_start (void);
902 extern void init_function_start (tree);
903 extern void stack_protect_epilogue (void);
904 extern void expand_function_start (tree);
905 extern void expand_dummy_function_end (void);
906
907 extern void thread_prologue_and_epilogue_insns (void);
908
909 #ifdef RTX_CODE
910 extern void diddle_return_value (void (*)(rtx, void*), void*);
911 extern void clobber_return_register (void);
912 #endif
913
914 extern void do_warn_unused_parameter (tree);
915 extern void expand_function_end (void);
916 extern rtx get_arg_pointer_save_area (void);
917 extern void maybe_copy_prologue_epilogue_insn (rtx, rtx);
918 extern int prologue_epilogue_contains (const_rtx);
919 extern void emit_return_into_block (bool simple_p, basic_block bb);
920 extern void set_return_jump_label (rtx_insn *);
921 extern bool active_insn_between (rtx_insn *head, rtx_insn *tail);
922 extern vec<edge> convert_jumps_to_returns (basic_block last_bb, bool simple_p,
923 vec<edge> unconverted);
924 extern basic_block emit_return_for_exit (edge exit_fallthru_edge,
925 bool simple_p);
926 extern void reposition_prologue_and_epilogue_notes (void);
927
928 /* Returns the name of the current function. */
929 extern const char *fndecl_name (tree);
930 extern const char *function_name (struct function *);
931 extern const char *current_function_name (void);
932
933 extern void used_types_insert (tree);
934
935 #endif /* GCC_FUNCTION_H */