1/* Structure for saving state for a nested function. 2 Copyright (C) 1989-2015 Free Software Foundation, Inc. 3 4This file is part of GCC. 5 6GCC is free software; you can redistribute it and/or modify it under 7the terms of the GNU General Public License as published by the Free 8Software Foundation; either version 3, or (at your option) any later 9version. 10 11GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12WARRANTY; without even the implied warranty of MERCHANTABILITY or 13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14for more details. 15 16You should have received a copy of the GNU General Public License 17along 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 29struct 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 36struct 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 /* The ends of the doubly-linked chain of rtl for the current function. 45 Both are reset to null at the start of rtl generation for the function. 46 47 start_sequence saves both of these on `sequence_stack' and then starts 48 a new, nested sequence of insns. */ 49 rtx_insn *x_first_insn; 50 rtx_insn *x_last_insn; 51 52 /* Stack of pending (incomplete) sequences saved by `start_sequence'. 53 Each element describes one pending sequence. 54 The main insn-chain is saved in the last element of the chain, 55 unless the chain is empty. */ 56 struct sequence_stack *sequence_stack; 57 58 /* INSN_UID for next insn emitted. 59 Reset to 1 for each function compiled. */ 60 int x_cur_insn_uid; 61 62 /* INSN_UID for next debug insn emitted. Only used if 63 --param min-nondebug-insn-uid=<value> is given with nonzero value. */ 64 int x_cur_debug_insn_uid; 65 66 /* The length of the regno_pointer_align, regno_decl, and x_regno_reg_rtx 67 vectors. Since these vectors are needed during the expansion phase when 68 the total number of registers in the function is not yet known, the 69 vectors are copied and made bigger when necessary. */ 70 int regno_pointer_align_length; 71 72 /* Indexed by pseudo register number, if nonzero gives the known alignment 73 for that pseudo (if REG_POINTER is set in x_regno_reg_rtx). 74 Allocated in parallel with x_regno_reg_rtx. */ 75 unsigned char * GTY((skip)) regno_pointer_align; 76}; 77 78 79/* Indexed by register number, gives an rtx for that register (and only 80 that register). For pseudo registers, it is the unique rtx for 81 that pseudo. For hard registers, it is an rtx of the mode specified 82 by reg_raw_mode. 83 84 FIXME: We could put it into emit_status struct, but gengtype is not 85 able to deal with length attribute nested in top level structures. */ 86 87extern GTY ((length ("crtl->emit.x_reg_rtx_no"))) rtx * regno_reg_rtx; 88 89/* For backward compatibility... eventually these should all go away. */ 90#define reg_rtx_no (crtl->emit.x_reg_rtx_no) 91#define seq_stack (crtl->emit.sequence_stack) 92 93#define REGNO_POINTER_ALIGN(REGNO) (crtl->emit.regno_pointer_align[REGNO]) 94 95struct GTY(()) expr_status { 96 /* Number of units that we should eventually pop off the stack. 97 These are the arguments to function calls that have already returned. */ 98 int x_pending_stack_adjust; 99 100 /* Under some ABIs, it is the caller's responsibility to pop arguments 101 pushed for function calls. A naive implementation would simply pop 102 the arguments immediately after each call. However, if several 103 function calls are made in a row, it is typically cheaper to pop 104 all the arguments after all of the calls are complete since a 105 single pop instruction can be used. Therefore, GCC attempts to 106 defer popping the arguments until absolutely necessary. (For 107 example, at the end of a conditional, the arguments must be popped, 108 since code outside the conditional won't know whether or not the 109 arguments need to be popped.) 110 111 When INHIBIT_DEFER_POP is nonzero, however, the compiler does not 112 attempt to defer pops. Instead, the stack is popped immediately 113 after each call. Rather then setting this variable directly, use 114 NO_DEFER_POP and OK_DEFER_POP. */ 115 int x_inhibit_defer_pop; 116 117 /* If PREFERRED_STACK_BOUNDARY and PUSH_ROUNDING are defined, the stack 118 boundary can be momentarily unaligned while pushing the arguments. 119 Record the delta since last aligned boundary here in order to get 120 stack alignment in the nested function calls working right. */ 121 int x_stack_pointer_delta; 122 123 /* Nonzero means __builtin_saveregs has already been done in this function. 124 The value is the pseudoreg containing the value __builtin_saveregs 125 returned. */ 126 rtx x_saveregs_value; 127 128 /* Similarly for __builtin_apply_args. */ 129 rtx x_apply_args_value; 130 131 /* List of labels that must never be deleted. */ 132 rtx_insn_list *x_forced_labels; 133}; 134 135typedef struct call_site_record_d *call_site_record; 136 137/* RTL representation of exception handling. */ 138struct GTY(()) rtl_eh { 139 rtx ehr_stackadj; 140 rtx ehr_handler; 141 rtx_code_label *ehr_label; 142 143 rtx sjlj_fc; 144 rtx_insn *sjlj_exit_after; 145 146 vec<uchar, va_gc> *action_record_data; 147 148 vec<call_site_record, va_gc> *call_site_record_v[2]; 149}; 150 151#define pending_stack_adjust (crtl->expr.x_pending_stack_adjust) 152#define inhibit_defer_pop (crtl->expr.x_inhibit_defer_pop) 153#define saveregs_value (crtl->expr.x_saveregs_value) 154#define apply_args_value (crtl->expr.x_apply_args_value) 155#define forced_labels (crtl->expr.x_forced_labels) 156#define stack_pointer_delta (crtl->expr.x_stack_pointer_delta) 157 158struct gimple_df; 159struct temp_slot; 160typedef struct temp_slot *temp_slot_p; 161struct call_site_record_d; 162struct dw_fde_node; 163 164class ipa_opt_pass_d; 165typedef ipa_opt_pass_d *ipa_opt_pass; 166 167 168struct GTY(()) varasm_status { 169 /* If we're using a per-function constant pool, this is it. */ 170 struct rtx_constant_pool *pool; 171 172 /* Number of tree-constants deferred during the expansion of this 173 function. */ 174 unsigned int deferred_constants; 175}; 176 177/* Information mainlined about RTL representation of incoming arguments. */ 178struct GTY(()) incoming_args { 179 /* Number of bytes of args popped by function being compiled on its return. 180 Zero if no bytes are to be popped. 181 May affect compilation of return insn or of function epilogue. */ 182 int pops_args; 183 184 /* If function's args have a fixed size, this is that size, in bytes. 185 Otherwise, it is -1. 186 May affect compilation of return insn or of function epilogue. */ 187 int size; 188 189 /* # bytes the prologue should push and pretend that the caller pushed them. 190 The prologue must do this, but only if parms can be passed in 191 registers. */ 192 int pretend_args_size; 193 194 /* This is the offset from the arg pointer to the place where the first 195 anonymous arg can be found, if there is one. */ 196 rtx arg_offset_rtx; 197 198 /* Quantities of various kinds of registers 199 used for the current function's args. */ 200 CUMULATIVE_ARGS info; 201 202 /* The arg pointer hard register, or the pseudo into which it was copied. */ 203 rtx internal_arg_pointer; 204}; 205 206/* Data for function partitioning. */ 207struct GTY(()) function_subsections { 208 /* Assembly labels for the hot and cold text sections, to 209 be used by debugger functions for determining the size of text 210 sections. */ 211 212 const char *hot_section_label; 213 const char *cold_section_label; 214 const char *hot_section_end_label; 215 const char *cold_section_end_label; 216}; 217 218/* Describe an empty area of space in the stack frame. These can be chained 219 into a list; this is used to keep track of space wasted for alignment 220 reasons. */ 221struct GTY(()) frame_space 222{ 223 struct frame_space *next; 224 225 HOST_WIDE_INT start; 226 HOST_WIDE_INT length; 227}; 228 229/* Datastructures maintained for currently processed function in RTL form. */ 230struct GTY(()) rtl_data { 231 struct expr_status expr; 232 struct emit_status emit; 233 struct varasm_status varasm; 234 struct incoming_args args; 235 struct function_subsections subsections; 236 struct rtl_eh eh; 237 238 /* For function.c */ 239 240 /* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is 241 defined, the needed space is pushed by the prologue. */ 242 int outgoing_args_size; 243 244 /* If nonzero, an RTL expression for the location at which the current 245 function returns its result. If the current function returns its 246 result in a register, current_function_return_rtx will always be 247 the hard register containing the result. */ 248 rtx return_rtx; 249 /* If nonxero, an RTL expression for the lcoation at which the current 250 function returns bounds for its result. */ 251 rtx return_bnd; 252 253 /* Vector of initial-value pairs. Each pair consists of a pseudo 254 register of approprite mode that stores the initial value a hard 255 register REGNO, and that hard register itself. */ 256 /* ??? This could be a VEC but there is currently no way to define an 257 opaque VEC type. */ 258 struct initial_value_struct *hard_reg_initial_vals; 259 260 /* A variable living at the top of the frame that holds a known value. 261 Used for detecting stack clobbers. */ 262 tree stack_protect_guard; 263 264 /* List (chain of INSN_LIST) of labels heading the current handlers for 265 nonlocal gotos. */ 266 rtx_insn_list *x_nonlocal_goto_handler_labels; 267 268 /* Label that will go on function epilogue. 269 Jumping to this label serves as a "return" instruction 270 on machines which require execution of the epilogue on all returns. */ 271 rtx_code_label *x_return_label; 272 273 /* Label that will go on the end of function epilogue. 274 Jumping to this label serves as a "naked return" instruction 275 on machines which require execution of the epilogue on all returns. */ 276 rtx_code_label *x_naked_return_label; 277 278 /* List (chain of EXPR_LISTs) of all stack slots in this function. 279 Made for the sake of unshare_all_rtl. */ 280 rtx_expr_list *x_stack_slot_list; 281 282 /* List of empty areas in the stack frame. */ 283 struct frame_space *frame_space_list; 284 285 /* Place after which to insert the tail_recursion_label if we need one. */ 286 rtx_note *x_stack_check_probe_note; 287 288 /* Location at which to save the argument pointer if it will need to be 289 referenced. There are two cases where this is done: if nonlocal gotos 290 exist, or if vars stored at an offset from the argument pointer will be 291 needed by inner routines. */ 292 rtx x_arg_pointer_save_area; 293 294 /* Dynamic Realign Argument Pointer used for realigning stack. */ 295 rtx drap_reg; 296 297 /* Offset to end of allocated area of stack frame. 298 If stack grows down, this is the address of the last stack slot allocated. 299 If stack grows up, this is the address for the next slot. */ 300 HOST_WIDE_INT x_frame_offset; 301 302 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */ 303 rtx_insn *x_parm_birth_insn; 304 305 /* List of all used temporaries allocated, by level. */ 306 vec<temp_slot_p, va_gc> *x_used_temp_slots; 307 308 /* List of available temp slots. */ 309 struct temp_slot *x_avail_temp_slots; 310 311 /* Current nesting level for temporaries. */ 312 int x_temp_slot_level; 313 314 /* The largest alignment needed on the stack, including requirement 315 for outgoing stack alignment. */ 316 unsigned int stack_alignment_needed; 317 318 /* Preferred alignment of the end of stack frame, which is preferred 319 to call other functions. */ 320 unsigned int preferred_stack_boundary; 321 322 /* The minimum alignment of parameter stack. */ 323 unsigned int parm_stack_boundary; 324 325 /* The largest alignment of slot allocated on the stack. */ 326 unsigned int max_used_stack_slot_alignment; 327 328 /* The stack alignment estimated before reload, with consideration of 329 following factors: 330 1. Alignment of local stack variables (max_used_stack_slot_alignment) 331 2. Alignment requirement to call other functions 332 (preferred_stack_boundary) 333 3. Alignment of non-local stack variables but might be spilled in 334 local stack. */ 335 unsigned int stack_alignment_estimated; 336 337 /* For reorg. */ 338 339 /* Nonzero if function being compiled called builtin_return_addr or 340 builtin_frame_address with nonzero count. */ 341 bool accesses_prior_frames; 342 343 /* Nonzero if the function calls __builtin_eh_return. */ 344 bool calls_eh_return; 345 346 /* Nonzero if function saves all registers, e.g. if it has a nonlocal 347 label that can reach the exit block via non-exceptional paths. */ 348 bool saves_all_registers; 349 350 /* Nonzero if function being compiled has nonlocal gotos to parent 351 function. */ 352 bool has_nonlocal_goto; 353 354 /* Nonzero if function being compiled has an asm statement. */ 355 bool has_asm_statement; 356 357 /* This bit is used by the exception handling logic. It is set if all 358 calls (if any) are sibling calls. Such functions do not have to 359 have EH tables generated, as they cannot throw. A call to such a 360 function, however, should be treated as throwing if any of its callees 361 can throw. */ 362 bool all_throwers_are_sibcalls; 363 364 /* Nonzero if stack limit checking should be enabled in the current 365 function. */ 366 bool limit_stack; 367 368 /* Nonzero if profiling code should be generated. */ 369 bool profile; 370 371 /* Nonzero if the current function uses the constant pool. */ 372 bool uses_const_pool; 373 374 /* Nonzero if the current function uses pic_offset_table_rtx. */ 375 bool uses_pic_offset_table; 376 377 /* Nonzero if the current function needs an lsda for exception handling. */ 378 bool uses_eh_lsda; 379 380 /* Set when the tail call has been produced. */ 381 bool tail_call_emit; 382 383 /* Nonzero if code to initialize arg_pointer_save_area has been emitted. */ 384 bool arg_pointer_save_area_init; 385 386 /* Nonzero if current function must be given a frame pointer. 387 Set in reload1.c or lra-eliminations.c if anything is allocated 388 on the stack there. */ 389 bool frame_pointer_needed; 390 391 /* When set, expand should optimize for speed. */ 392 bool maybe_hot_insn_p; 393 394 /* Nonzero if function stack realignment is needed. This flag may be 395 set twice: before and after reload. It is set before reload wrt 396 stack alignment estimation before reload. It will be changed after 397 reload if by then criteria of stack realignment is different. 398 The value set after reload is the accurate one and is finalized. */ 399 bool stack_realign_needed; 400 401 /* Nonzero if function stack realignment is tried. This flag is set 402 only once before reload. It affects register elimination. This 403 is used to generate DWARF debug info for stack variables. */ 404 bool stack_realign_tried; 405 406 /* Nonzero if function being compiled needs dynamic realigned 407 argument pointer (drap) if stack needs realigning. */ 408 bool need_drap; 409 410 /* Nonzero if function stack realignment estimation is done, namely 411 stack_realign_needed flag has been set before reload wrt estimated 412 stack alignment info. */ 413 bool stack_realign_processed; 414 415 /* Nonzero if function stack realignment has been finalized, namely 416 stack_realign_needed flag has been set and finalized after reload. */ 417 bool stack_realign_finalized; 418 419 /* True if dbr_schedule has already been called for this function. */ 420 bool dbr_scheduled_p; 421 422 /* True if current function can not throw. Unlike 423 TREE_NOTHROW (current_function_decl) it is set even for overwritable 424 function where currently compiled version of it is nothrow. */ 425 bool nothrow; 426 427 /* True if we performed shrink-wrapping for the current function. */ 428 bool shrink_wrapped; 429 430 /* Nonzero if function being compiled doesn't modify the stack pointer 431 (ignoring the prologue and epilogue). This is only valid after 432 pass_stack_ptr_mod has run. */ 433 bool sp_is_unchanging; 434 435 /* Nonzero if function being compiled doesn't contain any calls 436 (ignoring the prologue and epilogue). This is set prior to 437 local register allocation and is valid for the remaining 438 compiler passes. */ 439 bool is_leaf; 440 441 /* Nonzero if the function being compiled is a leaf function which only 442 uses leaf registers. This is valid after reload (specifically after 443 sched2) and is useful only if the port defines LEAF_REGISTERS. */ 444 bool uses_only_leaf_regs; 445 446 /* Nonzero if the function being compiled has undergone hot/cold partitioning 447 (under flag_reorder_blocks_and_partition) and has at least one cold 448 block. */ 449 bool has_bb_partition; 450 451 /* Nonzero if the function being compiled has completed the bb reordering 452 pass. */ 453 bool bb_reorder_complete; 454 455 /* Like regs_ever_live, but 1 if a reg is set or clobbered from an 456 asm. Unlike regs_ever_live, elements of this array corresponding 457 to eliminable regs (like the frame pointer) are set if an asm 458 sets them. */ 459 HARD_REG_SET asm_clobbers; 460}; 461 462#define return_label (crtl->x_return_label) 463#define naked_return_label (crtl->x_naked_return_label) 464#define stack_slot_list (crtl->x_stack_slot_list) 465#define parm_birth_insn (crtl->x_parm_birth_insn) 466#define frame_offset (crtl->x_frame_offset) 467#define stack_check_probe_note (crtl->x_stack_check_probe_note) 468#define arg_pointer_save_area (crtl->x_arg_pointer_save_area) 469#define used_temp_slots (crtl->x_used_temp_slots) 470#define avail_temp_slots (crtl->x_avail_temp_slots) 471#define temp_slot_level (crtl->x_temp_slot_level) 472#define nonlocal_goto_handler_labels (crtl->x_nonlocal_goto_handler_labels) 473#define frame_pointer_needed (crtl->frame_pointer_needed) 474#define stack_realign_fp (crtl->stack_realign_needed && !crtl->need_drap) 475#define stack_realign_drap (crtl->stack_realign_needed && crtl->need_drap) 476 477extern GTY(()) struct rtl_data x_rtl; 478 479/* Accessor to RTL datastructures. We keep them statically allocated now since 480 we never keep multiple functions. For threaded compiler we might however 481 want to do differently. */ 482#define crtl (&x_rtl) 483 484struct GTY(()) stack_usage 485{ 486 /* # of bytes of static stack space allocated by the function. */ 487 HOST_WIDE_INT static_stack_size; 488 489 /* # of bytes of dynamic stack space allocated by the function. This is 490 meaningful only if has_unbounded_dynamic_stack_size is zero. */ 491 HOST_WIDE_INT dynamic_stack_size; 492 493 /* # of bytes of space pushed onto the stack after the prologue. If 494 !ACCUMULATE_OUTGOING_ARGS, it contains the outgoing arguments. */ 495 int pushed_stack_size; 496 497 /* Nonzero if the amount of stack space allocated dynamically cannot 498 be bounded at compile-time. */ 499 unsigned int has_unbounded_dynamic_stack_size : 1; 500}; 501 502#define current_function_static_stack_size (cfun->su->static_stack_size) 503#define current_function_dynamic_stack_size (cfun->su->dynamic_stack_size) 504#define current_function_pushed_stack_size (cfun->su->pushed_stack_size) 505#define current_function_has_unbounded_dynamic_stack_size \ 506 (cfun->su->has_unbounded_dynamic_stack_size) 507#define current_function_allocates_dynamic_stack_space \ 508 (current_function_dynamic_stack_size != 0 \ 509 || current_function_has_unbounded_dynamic_stack_size) 510 511/* This structure can save all the important global and static variables 512 describing the status of the current function. */ 513 514struct GTY(()) function { 515 struct eh_status *eh; 516 517 /* The control flow graph for this function. */ 518 struct control_flow_graph *cfg; 519 520 /* GIMPLE body for this function. */ 521 gimple_seq gimple_body; 522 523 /* SSA and dataflow information. */ 524 struct gimple_df *gimple_df; 525 526 /* The loops in this function. */ 527 struct loops *x_current_loops; 528 529 /* The stack usage of this function. */ 530 struct stack_usage *su; 531 532 /* Value histograms attached to particular statements. */ 533 htab_t GTY((skip)) value_histograms; 534 535 /* For function.c. */ 536 537 /* Points to the FUNCTION_DECL of this function. */ 538 tree decl; 539 540 /* A PARM_DECL that should contain the static chain for this function. 541 It will be initialized at the beginning of the function. */ 542 tree static_chain_decl; 543 544 /* An expression that contains the non-local goto save area. The first 545 word is the saved frame pointer and the second is the saved stack 546 pointer. */ 547 tree nonlocal_goto_save_area; 548 549 /* Vector of function local variables, functions, types and constants. */ 550 vec<tree, va_gc> *local_decls; 551 552 /* In a Cilk function, the VAR_DECL for the frame descriptor. */ 553 tree cilk_frame_decl; 554 555 /* For md files. */ 556 557 /* tm.h can use this to store whatever it likes. */ 558 struct machine_function * GTY ((maybe_undef)) machine; 559 560 /* Language-specific code can use this to store whatever it likes. */ 561 struct language_function * language; 562 563 /* Used types hash table. */ 564 hash_set<tree> *GTY (()) used_types_hash; 565 566 /* Dwarf2 Frame Description Entry, containing the Call Frame Instructions 567 used for unwinding. Only set when either dwarf2 unwinding or dwarf2 568 debugging is enabled. */ 569 struct dw_fde_node *fde; 570 571 /* Last statement uid. */ 572 int last_stmt_uid; 573 574 /* Function sequence number for profiling, debugging, etc. */ 575 int funcdef_no; 576 577 /* Line number of the start of the function for debugging purposes. */ 578 location_t function_start_locus; 579 580 /* Line number of the end of the function. */ 581 location_t function_end_locus; 582 583 /* Properties used by the pass manager. */ 584 unsigned int curr_properties; 585 unsigned int last_verified; 586 587 /* Non-null if the function does something that would prevent it from 588 being copied; this applies to both versioning and inlining. Set to 589 a string describing the reason for failure. */ 590 const char * GTY((skip)) cannot_be_copied_reason; 591 592 /* Last assigned dependence info clique. */ 593 unsigned short last_clique; 594 595 /* Collected bit flags. */ 596 597 /* Number of units of general registers that need saving in stdarg 598 function. What unit is depends on the backend, either it is number 599 of bytes, or it can be number of registers. */ 600 unsigned int va_list_gpr_size : 8; 601 602 /* Number of units of floating point registers that need saving in stdarg 603 function. */ 604 unsigned int va_list_fpr_size : 8; 605 606 /* Nonzero if function being compiled can call setjmp. */ 607 unsigned int calls_setjmp : 1; 608 609 /* Nonzero if function being compiled can call alloca, 610 either as a subroutine or builtin. */ 611 unsigned int calls_alloca : 1; 612 613 /* This will indicate whether a function is a cilk function */ 614 unsigned int is_cilk_function : 1; 615 616 /* Nonzero if this is a Cilk function that spawns. */ 617 unsigned int calls_cilk_spawn : 1; 618 619 /* Nonzero if function being compiled receives nonlocal gotos 620 from nested functions. */ 621 unsigned int has_nonlocal_label : 1; 622 623 /* Nonzero if we've set cannot_be_copied_reason. I.e. if 624 (cannot_be_copied_set && !cannot_be_copied_reason), the function 625 can in fact be copied. */ 626 unsigned int cannot_be_copied_set : 1; 627 628 /* Nonzero if current function uses stdarg.h or equivalent. */ 629 unsigned int stdarg : 1; 630 631 unsigned int after_inlining : 1; 632 unsigned int always_inline_functions_inlined : 1; 633 634 /* Nonzero if function being compiled can throw synchronous non-call 635 exceptions. */ 636 unsigned int can_throw_non_call_exceptions : 1; 637 638 /* Nonzero if instructions that may throw exceptions but don't otherwise 639 contribute to the execution of the program can be deleted. */ 640 unsigned int can_delete_dead_exceptions : 1; 641 642 /* Fields below this point are not set for abstract functions; see 643 allocate_struct_function. */ 644 645 /* Nonzero if function being compiled needs to be given an address 646 where the value should be stored. */ 647 unsigned int returns_struct : 1; 648 649 /* Nonzero if function being compiled needs to 650 return the address of where it has put a structure value. */ 651 unsigned int returns_pcc_struct : 1; 652 653 /* Nonzero if this function has local DECL_HARD_REGISTER variables. 654 In this case code motion has to be done more carefully. */ 655 unsigned int has_local_explicit_reg_vars : 1; 656 657 /* Nonzero if the current function is a thunk, i.e., a lightweight 658 function implemented by the output_mi_thunk hook) that just 659 adjusts one of its arguments and forwards to another 660 function. */ 661 unsigned int is_thunk : 1; 662 663 /* Nonzero if the current function contains any loops with 664 loop->force_vectorize set. */ 665 unsigned int has_force_vectorize_loops : 1; 666 667 /* Nonzero if the current function contains any loops with 668 nonzero value in loop->simduid. */ 669 unsigned int has_simduid_loops : 1; 670 671 /* Set when the tail call has been identified. */ 672 unsigned int tail_call_marked : 1; 673}; 674 675/* Add the decl D to the local_decls list of FUN. */ 676 677void add_local_decl (struct function *fun, tree d); 678 679#define FOR_EACH_LOCAL_DECL(FUN, I, D) \ 680 FOR_EACH_VEC_SAFE_ELT_REVERSE ((FUN)->local_decls, I, D) 681 682/* If va_list_[gf]pr_size is set to this, it means we don't know how 683 many units need to be saved. */ 684#define VA_LIST_MAX_GPR_SIZE 255 685#define VA_LIST_MAX_FPR_SIZE 255 686 687/* The function currently being compiled. */ 688extern GTY(()) struct function *cfun; 689 690/* In order to ensure that cfun is not set directly, we redefine it so 691 that it is not an lvalue. Rather than assign to cfun, use 692 push_cfun or set_cfun. */ 693#define cfun (cfun + 0) 694 695/* Nonzero if we've already converted virtual regs to hard regs. */ 696extern int virtuals_instantiated; 697 698/* Nonzero if at least one trampoline has been created. */ 699extern int trampolines_created; 700 701struct GTY((for_user)) types_used_by_vars_entry { 702 tree type; 703 tree var_decl; 704}; 705 706struct used_type_hasher : ggc_hasher<types_used_by_vars_entry *> 707{ 708 static hashval_t hash (types_used_by_vars_entry *); 709 static bool equal (types_used_by_vars_entry *, types_used_by_vars_entry *); 710}; 711 712/* Hash table making the relationship between a global variable 713 and the types it references in its initializer. The key of the 714 entry is a referenced type, and the value is the DECL of the global 715 variable. types_use_by_vars_do_hash and types_used_by_vars_eq below are 716 the hash and equality functions to use for this hash table. */ 717extern GTY(()) hash_table<used_type_hasher> *types_used_by_vars_hash; 718 719void types_used_by_var_decl_insert (tree type, tree var_decl); 720 721/* During parsing of a global variable, this vector contains the types 722 referenced by the global variable. */ 723extern GTY(()) vec<tree, va_gc> *types_used_by_cur_var_decl; 724 725 726/* Return the loop tree of FN. */ 727 728inline struct loops * 729loops_for_fn (struct function *fn) 730{ 731 return fn->x_current_loops; 732} 733 734/* Set the loop tree of FN to LOOPS. */ 735 736inline void 737set_loops_for_fn (struct function *fn, struct loops *loops) 738{ 739 gcc_checking_assert (fn->x_current_loops == NULL || loops == NULL); 740 fn->x_current_loops = loops; 741} 742 743/* For backward compatibility... eventually these should all go away. */ 744#define current_function_funcdef_no (cfun->funcdef_no) 745 746#define current_loops (cfun->x_current_loops) 747#define dom_computed (cfun->cfg->x_dom_computed) 748#define n_bbs_in_dom_tree (cfun->cfg->x_n_bbs_in_dom_tree) 749#define VALUE_HISTOGRAMS(fun) (fun)->value_histograms 750 751/* A pointer to a function to create target specific, per-function 752 data structures. */ 753extern struct machine_function * (*init_machine_status) (void); 754 755enum direction {none, upward, downward}; 756 757/* Structure to record the size of a sequence of arguments 758 as the sum of a tree-expression and a constant. This structure is 759 also used to store offsets from the stack, which might be negative, 760 so the variable part must be ssizetype, not sizetype. */ 761 762struct args_size 763{ 764 HOST_WIDE_INT constant; 765 tree var; 766}; 767 768/* Package up various arg related fields of struct args for 769 locate_and_pad_parm. */ 770struct locate_and_pad_arg_data 771{ 772 /* Size of this argument on the stack, rounded up for any padding it 773 gets. If REG_PARM_STACK_SPACE is defined, then register parms are 774 counted here, otherwise they aren't. */ 775 struct args_size size; 776 /* Offset of this argument from beginning of stack-args. */ 777 struct args_size offset; 778 /* Offset to the start of the stack slot. Different from OFFSET 779 if this arg pads downward. */ 780 struct args_size slot_offset; 781 /* The amount that the stack pointer needs to be adjusted to 782 force alignment for the next argument. */ 783 struct args_size alignment_pad; 784 /* Which way we should pad this arg. */ 785 enum direction where_pad; 786 /* slot_offset is at least this aligned. */ 787 unsigned int boundary; 788}; 789 790/* Add the value of the tree INC to the `struct args_size' TO. */ 791 792#define ADD_PARM_SIZE(TO, INC) \ 793do { \ 794 tree inc = (INC); \ 795 if (tree_fits_shwi_p (inc)) \ 796 (TO).constant += tree_to_shwi (inc); \ 797 else if ((TO).var == 0) \ 798 (TO).var = fold_convert (ssizetype, inc); \ 799 else \ 800 (TO).var = size_binop (PLUS_EXPR, (TO).var, \ 801 fold_convert (ssizetype, inc)); \ 802} while (0) 803 804#define SUB_PARM_SIZE(TO, DEC) \ 805do { \ 806 tree dec = (DEC); \ 807 if (tree_fits_shwi_p (dec)) \ 808 (TO).constant -= tree_to_shwi (dec); \ 809 else if ((TO).var == 0) \ 810 (TO).var = size_binop (MINUS_EXPR, ssize_int (0), \ 811 fold_convert (ssizetype, dec)); \ 812 else \ 813 (TO).var = size_binop (MINUS_EXPR, (TO).var, \ 814 fold_convert (ssizetype, dec)); \ 815} while (0) 816 817/* Convert the implicit sum in a `struct args_size' into a tree 818 of type ssizetype. */ 819#define ARGS_SIZE_TREE(SIZE) \ 820((SIZE).var == 0 ? ssize_int ((SIZE).constant) \ 821 : size_binop (PLUS_EXPR, fold_convert (ssizetype, (SIZE).var), \ 822 ssize_int ((SIZE).constant))) 823 824/* Convert the implicit sum in a `struct args_size' into an rtx. */ 825#define ARGS_SIZE_RTX(SIZE) \ 826((SIZE).var == 0 ? GEN_INT ((SIZE).constant) \ 827 : expand_normal (ARGS_SIZE_TREE (SIZE))) 828 829#define ASLK_REDUCE_ALIGN 1 830#define ASLK_RECORD_PAD 2 831 832 833 834extern void push_function_context (void); 835extern void pop_function_context (void); 836 837/* Save and restore status information for a nested function. */ 838extern void free_after_parsing (struct function *); 839extern void free_after_compilation (struct function *); 840 841/* Return size needed for stack frame based on slots so far allocated. 842 This size counts from zero. It is not rounded to STACK_BOUNDARY; 843 the caller may have to do that. */ 844extern HOST_WIDE_INT get_frame_size (void); 845 846/* Issue an error message and return TRUE if frame OFFSET overflows in 847 the signed target pointer arithmetics for function FUNC. Otherwise 848 return FALSE. */ 849extern bool frame_offset_overflow (HOST_WIDE_INT, tree); 850 851extern rtx assign_stack_local_1 (machine_mode, HOST_WIDE_INT, int, int); 852extern rtx assign_stack_local (machine_mode, HOST_WIDE_INT, int); 853extern rtx assign_stack_temp_for_type (machine_mode, HOST_WIDE_INT, tree); 854extern rtx assign_stack_temp (machine_mode, HOST_WIDE_INT); 855extern rtx assign_temp (tree, int, int); 856extern void update_temp_slot_address (rtx, rtx); 857extern void preserve_temp_slots (rtx); 858extern void free_temp_slots (void); 859extern void push_temp_slots (void); 860extern void pop_temp_slots (void); 861extern void init_temp_slots (void); 862extern rtx get_hard_reg_initial_reg (rtx); 863extern rtx get_hard_reg_initial_val (machine_mode, unsigned int); 864extern rtx has_hard_reg_initial_val (machine_mode, unsigned int); 865 866/* Called from gimple_expand_cfg. */ 867extern unsigned int emit_initial_value_sets (void); 868 869extern bool initial_value_entry (int i, rtx *, rtx *); 870extern void instantiate_decl_rtl (rtx x); 871extern int aggregate_value_p (const_tree, const_tree); 872extern bool use_register_for_decl (const_tree); 873extern bool pass_by_reference (CUMULATIVE_ARGS *, machine_mode, 874 tree, bool); 875extern bool reference_callee_copied (CUMULATIVE_ARGS *, machine_mode, 876 tree, bool); 877extern gimple_seq gimplify_parameters (void); 878extern void locate_and_pad_parm (machine_mode, tree, int, int, int, 879 tree, struct args_size *, 880 struct locate_and_pad_arg_data *); 881extern void generate_setjmp_warnings (void); 882 883/* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END}, 884 and create duplicate blocks. */ 885extern void reorder_blocks (void); 886extern void clear_block_marks (tree); 887extern tree blocks_nreverse (tree); 888extern tree block_chainon (tree, tree); 889 890/* Set BLOCK_NUMBER for all the blocks in FN. */ 891extern void number_blocks (tree); 892 893/* cfun shouldn't be set directly; use one of these functions instead. */ 894extern void set_cfun (struct function *new_cfun); 895extern void push_cfun (struct function *new_cfun); 896extern void pop_cfun (void); 897 898extern int get_next_funcdef_no (void); 899extern int get_last_funcdef_no (void); 900extern void allocate_struct_function (tree, bool); 901extern void push_struct_function (tree fndecl); 902extern void init_dummy_function_start (void); 903extern void init_function_start (tree); 904extern void stack_protect_epilogue (void); 905extern void expand_function_start (tree); 906extern void expand_dummy_function_end (void); 907 908extern void thread_prologue_and_epilogue_insns (void); 909 910#ifdef RTX_CODE 911extern void diddle_return_value (void (*)(rtx, void*), void*); 912extern void clobber_return_register (void); 913#endif 914 915extern void do_warn_unused_parameter (tree); 916extern void expand_function_end (void); 917extern rtx get_arg_pointer_save_area (void); 918extern void maybe_copy_prologue_epilogue_insn (rtx, rtx); 919extern int prologue_epilogue_contains (const_rtx); 920extern void emit_return_into_block (bool simple_p, basic_block bb); 921extern void set_return_jump_label (rtx); 922extern bool active_insn_between (rtx_insn *head, rtx_insn *tail); 923extern vec<edge> convert_jumps_to_returns (basic_block last_bb, bool simple_p, 924 vec<edge> unconverted); 925extern basic_block emit_return_for_exit (edge exit_fallthru_edge, 926 bool simple_p); 927extern void reposition_prologue_and_epilogue_notes (void); 928 929/* Returns the name of the current function. */ 930extern const char *fndecl_name (tree); 931extern const char *function_name (struct function *); 932extern const char *current_function_name (void); 933 934extern void used_types_insert (tree); 935 936#endif /* GCC_FUNCTION_H */ 937