1 /* Exported functions from emit-rtl.c 2 Copyright (C) 2004-2019 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_EMIT_RTL_H 21 #define GCC_EMIT_RTL_H 22 23 struct temp_slot; 24 typedef struct temp_slot *temp_slot_p; 25 26 /* Information mainlined about RTL representation of incoming arguments. */ 27 struct GTY(()) incoming_args { 28 /* Number of bytes of args popped by function being compiled on its return. 29 Zero if no bytes are to be popped. 30 May affect compilation of return insn or of function epilogue. */ 31 poly_int64_pod pops_args; 32 33 /* If function's args have a fixed size, this is that size, in bytes. 34 Otherwise, it is -1. 35 May affect compilation of return insn or of function epilogue. */ 36 poly_int64_pod size; 37 38 /* # bytes the prologue should push and pretend that the caller pushed them. 39 The prologue must do this, but only if parms can be passed in 40 registers. */ 41 int pretend_args_size; 42 43 /* This is the offset from the arg pointer to the place where the first 44 anonymous arg can be found, if there is one. */ 45 rtx arg_offset_rtx; 46 47 /* Quantities of various kinds of registers 48 used for the current function's args. */ 49 CUMULATIVE_ARGS info; 50 51 /* The arg pointer hard register, or the pseudo into which it was copied. */ 52 rtx internal_arg_pointer; 53 }; 54 55 56 /* Datastructures maintained for currently processed function in RTL form. */ 57 struct GTY(()) rtl_data { 58 void init_stack_alignment (); 59 60 struct expr_status expr; 61 struct emit_status emit; 62 struct varasm_status varasm; 63 struct incoming_args args; 64 struct function_subsections subsections; 65 struct rtl_eh eh; 66 67 /* For function.c */ 68 69 /* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is 70 defined, the needed space is pushed by the prologue. */ 71 poly_int64_pod outgoing_args_size; 72 73 /* If nonzero, an RTL expression for the location at which the current 74 function returns its result. If the current function returns its 75 result in a register, current_function_return_rtx will always be 76 the hard register containing the result. */ 77 rtx return_rtx; 78 79 /* Vector of initial-value pairs. Each pair consists of a pseudo 80 register of approprite mode that stores the initial value a hard 81 register REGNO, and that hard register itself. */ 82 /* ??? This could be a VEC but there is currently no way to define an 83 opaque VEC type. */ 84 struct initial_value_struct *hard_reg_initial_vals; 85 86 /* A variable living at the top of the frame that holds a known value. 87 Used for detecting stack clobbers. */ 88 tree stack_protect_guard; 89 90 /* The __stack_chk_guard variable or expression holding the stack 91 protector canary value. */ 92 tree stack_protect_guard_decl; 93 94 /* List (chain of INSN_LIST) of labels heading the current handlers for 95 nonlocal gotos. */ 96 rtx_insn_list *x_nonlocal_goto_handler_labels; 97 98 /* Label that will go on function epilogue. 99 Jumping to this label serves as a "return" instruction 100 on machines which require execution of the epilogue on all returns. */ 101 rtx_code_label *x_return_label; 102 103 /* Label that will go on the end of function epilogue. 104 Jumping to this label serves as a "naked return" instruction 105 on machines which require execution of the epilogue on all returns. */ 106 rtx_code_label *x_naked_return_label; 107 108 /* List (chain of EXPR_LISTs) of all stack slots in this function. 109 Made for the sake of unshare_all_rtl. */ 110 vec<rtx, va_gc> *x_stack_slot_list; 111 112 /* List of empty areas in the stack frame. */ 113 struct frame_space *frame_space_list; 114 115 /* Place after which to insert the tail_recursion_label if we need one. */ 116 rtx_note *x_stack_check_probe_note; 117 118 /* Location at which to save the argument pointer if it will need to be 119 referenced. There are two cases where this is done: if nonlocal gotos 120 exist, or if vars stored at an offset from the argument pointer will be 121 needed by inner routines. */ 122 rtx x_arg_pointer_save_area; 123 124 /* Dynamic Realign Argument Pointer used for realigning stack. */ 125 rtx drap_reg; 126 127 /* Offset to end of allocated area of stack frame. 128 If stack grows down, this is the address of the last stack slot allocated. 129 If stack grows up, this is the address for the next slot. */ 130 poly_int64_pod x_frame_offset; 131 132 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */ 133 rtx_insn *x_parm_birth_insn; 134 135 /* List of all used temporaries allocated, by level. */ 136 vec<temp_slot_p, va_gc> *x_used_temp_slots; 137 138 /* List of available temp slots. */ 139 struct temp_slot *x_avail_temp_slots; 140 141 /* Current nesting level for temporaries. */ 142 int x_temp_slot_level; 143 144 /* The largest alignment needed on the stack, including requirement 145 for outgoing stack alignment. */ 146 unsigned int stack_alignment_needed; 147 148 /* Preferred alignment of the end of stack frame, which is preferred 149 to call other functions. */ 150 unsigned int preferred_stack_boundary; 151 152 /* The minimum alignment of parameter stack. */ 153 unsigned int parm_stack_boundary; 154 155 /* The largest alignment of slot allocated on the stack. */ 156 unsigned int max_used_stack_slot_alignment; 157 158 /* The stack alignment estimated before reload, with consideration of 159 following factors: 160 1. Alignment of local stack variables (max_used_stack_slot_alignment) 161 2. Alignment requirement to call other functions 162 (preferred_stack_boundary) 163 3. Alignment of non-local stack variables but might be spilled in 164 local stack. */ 165 unsigned int stack_alignment_estimated; 166 167 /* For reorg. */ 168 169 /* Nonzero if function being compiled called builtin_return_addr or 170 builtin_frame_address with nonzero count. */ 171 bool accesses_prior_frames; 172 173 /* Nonzero if the function calls __builtin_eh_return. */ 174 bool calls_eh_return; 175 176 /* Nonzero if function saves all registers, e.g. if it has a nonlocal 177 label that can reach the exit block via non-exceptional paths. */ 178 bool saves_all_registers; 179 180 /* Nonzero if function being compiled has nonlocal gotos to parent 181 function. */ 182 bool has_nonlocal_goto; 183 184 /* Nonzero if function being compiled has an asm statement. */ 185 bool has_asm_statement; 186 187 /* This bit is used by the exception handling logic. It is set if all 188 calls (if any) are sibling calls. Such functions do not have to 189 have EH tables generated, as they cannot throw. A call to such a 190 function, however, should be treated as throwing if any of its callees 191 can throw. */ 192 bool all_throwers_are_sibcalls; 193 194 /* Nonzero if stack limit checking should be enabled in the current 195 function. */ 196 bool limit_stack; 197 198 /* Nonzero if profiling code should be generated. */ 199 bool profile; 200 201 /* Nonzero if the current function uses the constant pool. */ 202 bool uses_const_pool; 203 204 /* Nonzero if the current function uses pic_offset_table_rtx. */ 205 bool uses_pic_offset_table; 206 207 /* Nonzero if the current function needs an lsda for exception handling. */ 208 bool uses_eh_lsda; 209 210 /* Set when the tail call has been produced. */ 211 bool tail_call_emit; 212 213 /* Nonzero if code to initialize arg_pointer_save_area has been emitted. */ 214 bool arg_pointer_save_area_init; 215 216 /* Nonzero if current function must be given a frame pointer. 217 Set in reload1.c or lra-eliminations.c if anything is allocated 218 on the stack there. */ 219 bool frame_pointer_needed; 220 221 /* When set, expand should optimize for speed. */ 222 bool maybe_hot_insn_p; 223 224 /* Nonzero if function stack realignment is needed. This flag may be 225 set twice: before and after reload. It is set before reload wrt 226 stack alignment estimation before reload. It will be changed after 227 reload if by then criteria of stack realignment is different. 228 The value set after reload is the accurate one and is finalized. */ 229 bool stack_realign_needed; 230 231 /* Nonzero if function stack realignment is tried. This flag is set 232 only once before reload. It affects register elimination. This 233 is used to generate DWARF debug info for stack variables. */ 234 bool stack_realign_tried; 235 236 /* Nonzero if function being compiled needs dynamic realigned 237 argument pointer (drap) if stack needs realigning. */ 238 bool need_drap; 239 240 /* Nonzero if function stack realignment estimation is done, namely 241 stack_realign_needed flag has been set before reload wrt estimated 242 stack alignment info. */ 243 bool stack_realign_processed; 244 245 /* Nonzero if function stack realignment has been finalized, namely 246 stack_realign_needed flag has been set and finalized after reload. */ 247 bool stack_realign_finalized; 248 249 /* True if dbr_schedule has already been called for this function. */ 250 bool dbr_scheduled_p; 251 252 /* True if current function cannot throw. Unlike 253 TREE_NOTHROW (current_function_decl) it is set even for overwritable 254 function where currently compiled version of it is nothrow. */ 255 bool nothrow; 256 257 /* True if we performed shrink-wrapping for the current function. */ 258 bool shrink_wrapped; 259 260 /* True if we performed shrink-wrapping for separate components for 261 the current function. */ 262 bool shrink_wrapped_separate; 263 264 /* Nonzero if function being compiled doesn't modify the stack pointer 265 (ignoring the prologue and epilogue). This is only valid after 266 pass_stack_ptr_mod has run. */ 267 bool sp_is_unchanging; 268 269 /* Nonzero if function being compiled doesn't contain any calls 270 (ignoring the prologue and epilogue). This is set prior to 271 register allocation in IRA and is valid for the remaining 272 compiler passes. */ 273 bool is_leaf; 274 275 /* Nonzero if the function being compiled is a leaf function which only 276 uses leaf registers. This is valid after reload (specifically after 277 sched2) and is useful only if the port defines LEAF_REGISTERS. */ 278 bool uses_only_leaf_regs; 279 280 /* Nonzero if the function being compiled has undergone hot/cold partitioning 281 (under flag_reorder_blocks_and_partition) and has at least one cold 282 block. */ 283 bool has_bb_partition; 284 285 /* Nonzero if the function being compiled has completed the bb reordering 286 pass. */ 287 bool bb_reorder_complete; 288 289 /* Like regs_ever_live, but 1 if a reg is set or clobbered from an 290 asm. Unlike regs_ever_live, elements of this array corresponding 291 to eliminable regs (like the frame pointer) are set if an asm 292 sets them. */ 293 HARD_REG_SET asm_clobbers; 294 295 /* The highest address seen during shorten_branches. */ 296 int max_insn_address; 297 }; 298 299 #define return_label (crtl->x_return_label) 300 #define naked_return_label (crtl->x_naked_return_label) 301 #define stack_slot_list (crtl->x_stack_slot_list) 302 #define parm_birth_insn (crtl->x_parm_birth_insn) 303 #define frame_offset (crtl->x_frame_offset) 304 #define stack_check_probe_note (crtl->x_stack_check_probe_note) 305 #define arg_pointer_save_area (crtl->x_arg_pointer_save_area) 306 #define used_temp_slots (crtl->x_used_temp_slots) 307 #define avail_temp_slots (crtl->x_avail_temp_slots) 308 #define temp_slot_level (crtl->x_temp_slot_level) 309 #define nonlocal_goto_handler_labels (crtl->x_nonlocal_goto_handler_labels) 310 #define frame_pointer_needed (crtl->frame_pointer_needed) 311 #define stack_realign_fp (crtl->stack_realign_needed && !crtl->need_drap) 312 #define stack_realign_drap (crtl->stack_realign_needed && crtl->need_drap) 313 314 extern GTY(()) struct rtl_data x_rtl; 315 316 /* Accessor to RTL datastructures. We keep them statically allocated now since 317 we never keep multiple functions. For threaded compiler we might however 318 want to do differently. */ 319 #define crtl (&x_rtl) 320 321 /* Return whether two MEM_ATTRs are equal. */ 322 bool mem_attrs_eq_p (const struct mem_attrs *, const struct mem_attrs *); 323 324 /* Set the alias set of MEM to SET. */ 325 extern void set_mem_alias_set (rtx, alias_set_type); 326 327 /* Set the alignment of MEM to ALIGN bits. */ 328 extern void set_mem_align (rtx, unsigned int); 329 330 /* Set the address space of MEM to ADDRSPACE. */ 331 extern void set_mem_addr_space (rtx, addr_space_t); 332 333 /* Set the expr for MEM to EXPR. */ 334 extern void set_mem_expr (rtx, tree); 335 336 /* Set the offset for MEM to OFFSET. */ 337 extern void set_mem_offset (rtx, poly_int64); 338 339 /* Clear the offset recorded for MEM. */ 340 extern void clear_mem_offset (rtx); 341 342 /* Set the size for MEM to SIZE. */ 343 extern void set_mem_size (rtx, poly_int64); 344 345 /* Clear the size recorded for MEM. */ 346 extern void clear_mem_size (rtx); 347 348 /* Set the attributes for MEM appropriate for a spill slot. */ 349 extern void set_mem_attrs_for_spill (rtx); 350 extern tree get_spill_slot_decl (bool); 351 352 /* Return a memory reference like MEMREF, but with its address changed to 353 ADDR. The caller is asserting that the actual piece of memory pointed 354 to is the same, just the form of the address is being changed, such as 355 by putting something into a register. */ 356 extern rtx replace_equiv_address (rtx, rtx, bool = false); 357 358 /* Likewise, but the reference is not required to be valid. */ 359 extern rtx replace_equiv_address_nv (rtx, rtx, bool = false); 360 361 extern rtx gen_blockage (void); 362 extern rtvec gen_rtvec (int, ...); 363 extern rtx copy_insn_1 (rtx); 364 extern rtx copy_insn (rtx); 365 extern rtx_insn *copy_delay_slot_insn (rtx_insn *); 366 extern rtx gen_int_mode (poly_int64, machine_mode); 367 extern rtx_insn *emit_copy_of_insn_after (rtx_insn *, rtx_insn *); 368 extern void set_reg_attrs_from_value (rtx, rtx); 369 extern void set_reg_attrs_for_parm (rtx, rtx); 370 extern void set_reg_attrs_for_decl_rtl (tree t, rtx x); 371 extern void adjust_reg_mode (rtx, machine_mode); 372 extern int mem_expr_equal_p (const_tree, const_tree); 373 extern rtx gen_int_shift_amount (machine_mode, poly_int64); 374 375 extern bool need_atomic_barrier_p (enum memmodel, bool); 376 377 /* Return the current sequence. */ 378 379 static inline struct sequence_stack * 380 get_current_sequence (void) 381 { 382 return &crtl->emit.seq; 383 } 384 385 /* Return the outermost sequence. */ 386 387 static inline struct sequence_stack * 388 get_topmost_sequence (void) 389 { 390 struct sequence_stack *seq, *top; 391 392 seq = get_current_sequence (); 393 do 394 { 395 top = seq; 396 seq = seq->next; 397 } while (seq); 398 return top; 399 } 400 401 /* Return the first insn of the current sequence or current function. */ 402 403 static inline rtx_insn * 404 get_insns (void) 405 { 406 return get_current_sequence ()->first; 407 } 408 409 /* Specify a new insn as the first in the chain. */ 410 411 static inline void 412 set_first_insn (rtx_insn *insn) 413 { 414 gcc_checking_assert (!insn || !PREV_INSN (insn)); 415 get_current_sequence ()->first = insn; 416 } 417 418 /* Return the last insn emitted in current sequence or current function. */ 419 420 static inline rtx_insn * 421 get_last_insn (void) 422 { 423 return get_current_sequence ()->last; 424 } 425 426 /* Specify a new insn as the last in the chain. */ 427 428 static inline void 429 set_last_insn (rtx_insn *insn) 430 { 431 gcc_checking_assert (!insn || !NEXT_INSN (insn)); 432 get_current_sequence ()->last = insn; 433 } 434 435 /* Return a number larger than any instruction's uid in this function. */ 436 437 static inline int 438 get_max_uid (void) 439 { 440 return crtl->emit.x_cur_insn_uid; 441 } 442 443 extern bool valid_for_const_vector_p (machine_mode, rtx); 444 extern rtx gen_const_vec_duplicate (machine_mode, rtx); 445 extern rtx gen_vec_duplicate (machine_mode, rtx); 446 447 extern rtx gen_const_vec_series (machine_mode, rtx, rtx); 448 extern rtx gen_vec_series (machine_mode, rtx, rtx); 449 450 extern void set_decl_incoming_rtl (tree, rtx, bool); 451 452 /* Return a memory reference like MEMREF, but with its mode changed 453 to MODE and its address changed to ADDR. 454 (VOIDmode means don't change the mode. 455 NULL for ADDR means don't change the address.) */ 456 extern rtx change_address (rtx, machine_mode, rtx); 457 458 /* Return a memory reference like MEMREF, but with its mode changed 459 to MODE and its address offset by OFFSET bytes. */ 460 #define adjust_address(MEMREF, MODE, OFFSET) \ 461 adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 0, 0) 462 463 /* Likewise, but the reference is not required to be valid. */ 464 #define adjust_address_nv(MEMREF, MODE, OFFSET) \ 465 adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 0, 0) 466 467 /* Return a memory reference like MEMREF, but with its mode changed 468 to MODE and its address offset by OFFSET bytes. Assume that it's 469 for a bitfield and conservatively drop the underlying object if we 470 cannot be sure to stay within its bounds. */ 471 #define adjust_bitfield_address(MEMREF, MODE, OFFSET) \ 472 adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, 0) 473 474 /* As for adjust_bitfield_address, but specify that the width of 475 BLKmode accesses is SIZE bytes. */ 476 #define adjust_bitfield_address_size(MEMREF, MODE, OFFSET, SIZE) \ 477 adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, SIZE) 478 479 /* Likewise, but the reference is not required to be valid. */ 480 #define adjust_bitfield_address_nv(MEMREF, MODE, OFFSET) \ 481 adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 1, 0) 482 483 /* Return a memory reference like MEMREF, but with its mode changed 484 to MODE and its address changed to ADDR, which is assumed to be 485 increased by OFFSET bytes from MEMREF. */ 486 #define adjust_automodify_address(MEMREF, MODE, ADDR, OFFSET) \ 487 adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 1) 488 489 /* Likewise, but the reference is not required to be valid. */ 490 #define adjust_automodify_address_nv(MEMREF, MODE, ADDR, OFFSET) \ 491 adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 0) 492 493 extern rtx adjust_address_1 (rtx, machine_mode, poly_int64, int, int, 494 int, poly_int64); 495 extern rtx adjust_automodify_address_1 (rtx, machine_mode, rtx, 496 poly_int64, int); 497 498 /* Return a memory reference like MEMREF, but whose address is changed by 499 adding OFFSET, an RTX, to it. POW2 is the highest power of two factor 500 known to be in OFFSET (possibly 1). */ 501 extern rtx offset_address (rtx, rtx, unsigned HOST_WIDE_INT); 502 503 /* Given REF, a MEM, and T, either the type of X or the expression 504 corresponding to REF, set the memory attributes. OBJECTP is nonzero 505 if we are making a new object of this type. */ 506 extern void set_mem_attributes (rtx, tree, int); 507 508 /* Similar, except that BITPOS has not yet been applied to REF, so if 509 we alter MEM_OFFSET according to T then we should subtract BITPOS 510 expecting that it'll be added back in later. */ 511 extern void set_mem_attributes_minus_bitpos (rtx, tree, int, poly_int64); 512 513 /* Return OFFSET if XEXP (MEM, 0) - OFFSET is known to be ALIGN 514 bits aligned for 0 <= OFFSET < ALIGN / BITS_PER_UNIT, or 515 -1 if not known. */ 516 extern int get_mem_align_offset (rtx, unsigned int); 517 518 /* Return a memory reference like MEMREF, but with its mode widened to 519 MODE and adjusted by OFFSET. */ 520 extern rtx widen_memory_access (rtx, machine_mode, poly_int64); 521 522 extern void maybe_set_max_label_num (rtx_code_label *x); 523 524 #endif /* GCC_EMIT_RTL_H */ 525