1 /* Exported functions from emit-rtl.c 2 Copyright (C) 2004-2018 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 /* If nonxero, an RTL expression for the lcoation at which the current 79 function returns bounds for its result. */ 80 rtx return_bnd; 81 82 /* Vector of initial-value pairs. Each pair consists of a pseudo 83 register of approprite mode that stores the initial value a hard 84 register REGNO, and that hard register itself. */ 85 /* ??? This could be a VEC but there is currently no way to define an 86 opaque VEC type. */ 87 struct initial_value_struct *hard_reg_initial_vals; 88 89 /* A variable living at the top of the frame that holds a known value. 90 Used for detecting stack clobbers. */ 91 tree stack_protect_guard; 92 93 /* List (chain of INSN_LIST) of labels heading the current handlers for 94 nonlocal gotos. */ 95 rtx_insn_list *x_nonlocal_goto_handler_labels; 96 97 /* Label that will go on function epilogue. 98 Jumping to this label serves as a "return" instruction 99 on machines which require execution of the epilogue on all returns. */ 100 rtx_code_label *x_return_label; 101 102 /* Label that will go on the end of function epilogue. 103 Jumping to this label serves as a "naked return" instruction 104 on machines which require execution of the epilogue on all returns. */ 105 rtx_code_label *x_naked_return_label; 106 107 /* List (chain of EXPR_LISTs) of all stack slots in this function. 108 Made for the sake of unshare_all_rtl. */ 109 vec<rtx, va_gc> *x_stack_slot_list; 110 111 /* List of empty areas in the stack frame. */ 112 struct frame_space *frame_space_list; 113 114 /* Place after which to insert the tail_recursion_label if we need one. */ 115 rtx_note *x_stack_check_probe_note; 116 117 /* Location at which to save the argument pointer if it will need to be 118 referenced. There are two cases where this is done: if nonlocal gotos 119 exist, or if vars stored at an offset from the argument pointer will be 120 needed by inner routines. */ 121 rtx x_arg_pointer_save_area; 122 123 /* Dynamic Realign Argument Pointer used for realigning stack. */ 124 rtx drap_reg; 125 126 /* Offset to end of allocated area of stack frame. 127 If stack grows down, this is the address of the last stack slot allocated. 128 If stack grows up, this is the address for the next slot. */ 129 poly_int64_pod x_frame_offset; 130 131 /* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */ 132 rtx_insn *x_parm_birth_insn; 133 134 /* List of all used temporaries allocated, by level. */ 135 vec<temp_slot_p, va_gc> *x_used_temp_slots; 136 137 /* List of available temp slots. */ 138 struct temp_slot *x_avail_temp_slots; 139 140 /* Current nesting level for temporaries. */ 141 int x_temp_slot_level; 142 143 /* The largest alignment needed on the stack, including requirement 144 for outgoing stack alignment. */ 145 unsigned int stack_alignment_needed; 146 147 /* Preferred alignment of the end of stack frame, which is preferred 148 to call other functions. */ 149 unsigned int preferred_stack_boundary; 150 151 /* The minimum alignment of parameter stack. */ 152 unsigned int parm_stack_boundary; 153 154 /* The largest alignment of slot allocated on the stack. */ 155 unsigned int max_used_stack_slot_alignment; 156 157 /* The stack alignment estimated before reload, with consideration of 158 following factors: 159 1. Alignment of local stack variables (max_used_stack_slot_alignment) 160 2. Alignment requirement to call other functions 161 (preferred_stack_boundary) 162 3. Alignment of non-local stack variables but might be spilled in 163 local stack. */ 164 unsigned int stack_alignment_estimated; 165 166 /* For reorg. */ 167 168 /* Nonzero if function being compiled called builtin_return_addr or 169 builtin_frame_address with nonzero count. */ 170 bool accesses_prior_frames; 171 172 /* Nonzero if the function calls __builtin_eh_return. */ 173 bool calls_eh_return; 174 175 /* Nonzero if function saves all registers, e.g. if it has a nonlocal 176 label that can reach the exit block via non-exceptional paths. */ 177 bool saves_all_registers; 178 179 /* Nonzero if function being compiled has nonlocal gotos to parent 180 function. */ 181 bool has_nonlocal_goto; 182 183 /* Nonzero if function being compiled has an asm statement. */ 184 bool has_asm_statement; 185 186 /* This bit is used by the exception handling logic. It is set if all 187 calls (if any) are sibling calls. Such functions do not have to 188 have EH tables generated, as they cannot throw. A call to such a 189 function, however, should be treated as throwing if any of its callees 190 can throw. */ 191 bool all_throwers_are_sibcalls; 192 193 /* Nonzero if stack limit checking should be enabled in the current 194 function. */ 195 bool limit_stack; 196 197 /* Nonzero if profiling code should be generated. */ 198 bool profile; 199 200 /* Nonzero if the current function uses the constant pool. */ 201 bool uses_const_pool; 202 203 /* Nonzero if the current function uses pic_offset_table_rtx. */ 204 bool uses_pic_offset_table; 205 206 /* Nonzero if the current function needs an lsda for exception handling. */ 207 bool uses_eh_lsda; 208 209 /* Set when the tail call has been produced. */ 210 bool tail_call_emit; 211 212 /* Nonzero if code to initialize arg_pointer_save_area has been emitted. */ 213 bool arg_pointer_save_area_init; 214 215 /* Nonzero if current function must be given a frame pointer. 216 Set in reload1.c or lra-eliminations.c if anything is allocated 217 on the stack there. */ 218 bool frame_pointer_needed; 219 220 /* When set, expand should optimize for speed. */ 221 bool maybe_hot_insn_p; 222 223 /* Nonzero if function stack realignment is needed. This flag may be 224 set twice: before and after reload. It is set before reload wrt 225 stack alignment estimation before reload. It will be changed after 226 reload if by then criteria of stack realignment is different. 227 The value set after reload is the accurate one and is finalized. */ 228 bool stack_realign_needed; 229 230 /* Nonzero if function stack realignment is tried. This flag is set 231 only once before reload. It affects register elimination. This 232 is used to generate DWARF debug info for stack variables. */ 233 bool stack_realign_tried; 234 235 /* Nonzero if function being compiled needs dynamic realigned 236 argument pointer (drap) if stack needs realigning. */ 237 bool need_drap; 238 239 /* Nonzero if function stack realignment estimation is done, namely 240 stack_realign_needed flag has been set before reload wrt estimated 241 stack alignment info. */ 242 bool stack_realign_processed; 243 244 /* Nonzero if function stack realignment has been finalized, namely 245 stack_realign_needed flag has been set and finalized after reload. */ 246 bool stack_realign_finalized; 247 248 /* True if dbr_schedule has already been called for this function. */ 249 bool dbr_scheduled_p; 250 251 /* True if current function can not throw. Unlike 252 TREE_NOTHROW (current_function_decl) it is set even for overwritable 253 function where currently compiled version of it is nothrow. */ 254 bool nothrow; 255 256 /* True if we performed shrink-wrapping for the current function. */ 257 bool shrink_wrapped; 258 259 /* True if we performed shrink-wrapping for separate components for 260 the current function. */ 261 bool shrink_wrapped_separate; 262 263 /* Nonzero if function being compiled doesn't modify the stack pointer 264 (ignoring the prologue and epilogue). This is only valid after 265 pass_stack_ptr_mod has run. */ 266 bool sp_is_unchanging; 267 268 /* Nonzero if function being compiled doesn't contain any calls 269 (ignoring the prologue and epilogue). This is set prior to 270 register allocation in IRA and is valid for the remaining 271 compiler passes. */ 272 bool is_leaf; 273 274 /* Nonzero if the function being compiled is a leaf function which only 275 uses leaf registers. This is valid after reload (specifically after 276 sched2) and is useful only if the port defines LEAF_REGISTERS. */ 277 bool uses_only_leaf_regs; 278 279 /* Nonzero if the function being compiled has undergone hot/cold partitioning 280 (under flag_reorder_blocks_and_partition) and has at least one cold 281 block. */ 282 bool has_bb_partition; 283 284 /* Nonzero if the function being compiled has completed the bb reordering 285 pass. */ 286 bool bb_reorder_complete; 287 288 /* Like regs_ever_live, but 1 if a reg is set or clobbered from an 289 asm. Unlike regs_ever_live, elements of this array corresponding 290 to eliminable regs (like the frame pointer) are set if an asm 291 sets them. */ 292 HARD_REG_SET asm_clobbers; 293 294 /* The highest address seen during shorten_branches. */ 295 int max_insn_address; 296 }; 297 298 #define return_label (crtl->x_return_label) 299 #define naked_return_label (crtl->x_naked_return_label) 300 #define stack_slot_list (crtl->x_stack_slot_list) 301 #define parm_birth_insn (crtl->x_parm_birth_insn) 302 #define frame_offset (crtl->x_frame_offset) 303 #define stack_check_probe_note (crtl->x_stack_check_probe_note) 304 #define arg_pointer_save_area (crtl->x_arg_pointer_save_area) 305 #define used_temp_slots (crtl->x_used_temp_slots) 306 #define avail_temp_slots (crtl->x_avail_temp_slots) 307 #define temp_slot_level (crtl->x_temp_slot_level) 308 #define nonlocal_goto_handler_labels (crtl->x_nonlocal_goto_handler_labels) 309 #define frame_pointer_needed (crtl->frame_pointer_needed) 310 #define stack_realign_fp (crtl->stack_realign_needed && !crtl->need_drap) 311 #define stack_realign_drap (crtl->stack_realign_needed && crtl->need_drap) 312 313 extern GTY(()) struct rtl_data x_rtl; 314 315 /* Accessor to RTL datastructures. We keep them statically allocated now since 316 we never keep multiple functions. For threaded compiler we might however 317 want to do differently. */ 318 #define crtl (&x_rtl) 319 320 /* Return whether two MEM_ATTRs are equal. */ 321 bool mem_attrs_eq_p (const struct mem_attrs *, const struct mem_attrs *); 322 323 /* Set the alias set of MEM to SET. */ 324 extern void set_mem_alias_set (rtx, alias_set_type); 325 326 /* Set the alignment of MEM to ALIGN bits. */ 327 extern void set_mem_align (rtx, unsigned int); 328 329 /* Set the address space of MEM to ADDRSPACE. */ 330 extern void set_mem_addr_space (rtx, addr_space_t); 331 332 /* Set the expr for MEM to EXPR. */ 333 extern void set_mem_expr (rtx, tree); 334 335 /* Set the offset for MEM to OFFSET. */ 336 extern void set_mem_offset (rtx, poly_int64); 337 338 /* Clear the offset recorded for MEM. */ 339 extern void clear_mem_offset (rtx); 340 341 /* Set the size for MEM to SIZE. */ 342 extern void set_mem_size (rtx, poly_int64); 343 344 /* Clear the size recorded for MEM. */ 345 extern void clear_mem_size (rtx); 346 347 /* Set the attributes for MEM appropriate for a spill slot. */ 348 extern void set_mem_attrs_for_spill (rtx); 349 extern tree get_spill_slot_decl (bool); 350 351 /* Return a memory reference like MEMREF, but with its address changed to 352 ADDR. The caller is asserting that the actual piece of memory pointed 353 to is the same, just the form of the address is being changed, such as 354 by putting something into a register. */ 355 extern rtx replace_equiv_address (rtx, rtx, bool = false); 356 357 /* Likewise, but the reference is not required to be valid. */ 358 extern rtx replace_equiv_address_nv (rtx, rtx, bool = false); 359 360 extern rtx gen_blockage (void); 361 extern rtvec gen_rtvec (int, ...); 362 extern rtx copy_insn_1 (rtx); 363 extern rtx copy_insn (rtx); 364 extern rtx_insn *copy_delay_slot_insn (rtx_insn *); 365 extern rtx gen_int_mode (poly_int64, machine_mode); 366 extern rtx_insn *emit_copy_of_insn_after (rtx_insn *, rtx_insn *); 367 extern void set_reg_attrs_from_value (rtx, rtx); 368 extern void set_reg_attrs_for_parm (rtx, rtx); 369 extern void set_reg_attrs_for_decl_rtl (tree t, rtx x); 370 extern void adjust_reg_mode (rtx, machine_mode); 371 extern int mem_expr_equal_p (const_tree, const_tree); 372 extern rtx gen_int_shift_amount (machine_mode, poly_int64); 373 374 extern bool need_atomic_barrier_p (enum memmodel, bool); 375 376 /* Return the current sequence. */ 377 378 static inline struct sequence_stack * 379 get_current_sequence (void) 380 { 381 return &crtl->emit.seq; 382 } 383 384 /* Return the outermost sequence. */ 385 386 static inline struct sequence_stack * 387 get_topmost_sequence (void) 388 { 389 struct sequence_stack *seq, *top; 390 391 seq = get_current_sequence (); 392 do 393 { 394 top = seq; 395 seq = seq->next; 396 } while (seq); 397 return top; 398 } 399 400 /* Return the first insn of the current sequence or current function. */ 401 402 static inline rtx_insn * 403 get_insns (void) 404 { 405 return get_current_sequence ()->first; 406 } 407 408 /* Specify a new insn as the first in the chain. */ 409 410 static inline void 411 set_first_insn (rtx_insn *insn) 412 { 413 gcc_checking_assert (!insn || !PREV_INSN (insn)); 414 get_current_sequence ()->first = insn; 415 } 416 417 /* Return the last insn emitted in current sequence or current function. */ 418 419 static inline rtx_insn * 420 get_last_insn (void) 421 { 422 return get_current_sequence ()->last; 423 } 424 425 /* Specify a new insn as the last in the chain. */ 426 427 static inline void 428 set_last_insn (rtx_insn *insn) 429 { 430 gcc_checking_assert (!insn || !NEXT_INSN (insn)); 431 get_current_sequence ()->last = insn; 432 } 433 434 /* Return a number larger than any instruction's uid in this function. */ 435 436 static inline int 437 get_max_uid (void) 438 { 439 return crtl->emit.x_cur_insn_uid; 440 } 441 442 extern bool valid_for_const_vector_p (machine_mode, rtx); 443 extern rtx gen_const_vec_duplicate (machine_mode, rtx); 444 extern rtx gen_vec_duplicate (machine_mode, rtx); 445 446 extern rtx gen_const_vec_series (machine_mode, rtx, rtx); 447 extern rtx gen_vec_series (machine_mode, rtx, rtx); 448 449 extern void set_decl_incoming_rtl (tree, rtx, bool); 450 451 /* Return a memory reference like MEMREF, but with its mode changed 452 to MODE and its address changed to ADDR. 453 (VOIDmode means don't change the mode. 454 NULL for ADDR means don't change the address.) */ 455 extern rtx change_address (rtx, machine_mode, rtx); 456 457 /* Return a memory reference like MEMREF, but with its mode changed 458 to MODE and its address offset by OFFSET bytes. */ 459 #define adjust_address(MEMREF, MODE, OFFSET) \ 460 adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 0, 0) 461 462 /* Likewise, but the reference is not required to be valid. */ 463 #define adjust_address_nv(MEMREF, MODE, OFFSET) \ 464 adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 0, 0) 465 466 /* Return a memory reference like MEMREF, but with its mode changed 467 to MODE and its address offset by OFFSET bytes. Assume that it's 468 for a bitfield and conservatively drop the underlying object if we 469 cannot be sure to stay within its bounds. */ 470 #define adjust_bitfield_address(MEMREF, MODE, OFFSET) \ 471 adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, 0) 472 473 /* As for adjust_bitfield_address, but specify that the width of 474 BLKmode accesses is SIZE bytes. */ 475 #define adjust_bitfield_address_size(MEMREF, MODE, OFFSET, SIZE) \ 476 adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, SIZE) 477 478 /* Likewise, but the reference is not required to be valid. */ 479 #define adjust_bitfield_address_nv(MEMREF, MODE, OFFSET) \ 480 adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 1, 0) 481 482 /* Return a memory reference like MEMREF, but with its mode changed 483 to MODE and its address changed to ADDR, which is assumed to be 484 increased by OFFSET bytes from MEMREF. */ 485 #define adjust_automodify_address(MEMREF, MODE, ADDR, OFFSET) \ 486 adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 1) 487 488 /* Likewise, but the reference is not required to be valid. */ 489 #define adjust_automodify_address_nv(MEMREF, MODE, ADDR, OFFSET) \ 490 adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 0) 491 492 extern rtx adjust_address_1 (rtx, machine_mode, poly_int64, int, int, 493 int, poly_int64); 494 extern rtx adjust_automodify_address_1 (rtx, machine_mode, rtx, 495 poly_int64, int); 496 497 /* Return a memory reference like MEMREF, but whose address is changed by 498 adding OFFSET, an RTX, to it. POW2 is the highest power of two factor 499 known to be in OFFSET (possibly 1). */ 500 extern rtx offset_address (rtx, rtx, unsigned HOST_WIDE_INT); 501 502 /* Given REF, a MEM, and T, either the type of X or the expression 503 corresponding to REF, set the memory attributes. OBJECTP is nonzero 504 if we are making a new object of this type. */ 505 extern void set_mem_attributes (rtx, tree, int); 506 507 /* Similar, except that BITPOS has not yet been applied to REF, so if 508 we alter MEM_OFFSET according to T then we should subtract BITPOS 509 expecting that it'll be added back in later. */ 510 extern void set_mem_attributes_minus_bitpos (rtx, tree, int, poly_int64); 511 512 /* Return OFFSET if XEXP (MEM, 0) - OFFSET is known to be ALIGN 513 bits aligned for 0 <= OFFSET < ALIGN / BITS_PER_UNIT, or 514 -1 if not known. */ 515 extern int get_mem_align_offset (rtx, unsigned int); 516 517 /* Return a memory reference like MEMREF, but with its mode widened to 518 MODE and adjusted by OFFSET. */ 519 extern rtx widen_memory_access (rtx, machine_mode, poly_int64); 520 521 extern void maybe_set_max_label_num (rtx_code_label *x); 522 523 #endif /* GCC_EMIT_RTL_H */ 524