1 /* Expands front end tree to back end RTL for GCC. 2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 3 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc. 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify it under 8 the terms of the GNU General Public License as published by the Free 9 Software Foundation; either version 2, or (at your option) any later 10 version. 11 12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13 WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15 for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING. If not, write to the Free 19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA 20 02111-1307, USA. */ 21 22 /* $FreeBSD$ */ 23 24 /* This file handles the generation of rtl code from tree structure 25 at the level of the function as a whole. 26 It creates the rtl expressions for parameters and auto variables 27 and has full responsibility for allocating stack slots. 28 29 `expand_function_start' is called at the beginning of a function, 30 before the function body is parsed, and `expand_function_end' is 31 called after parsing the body. 32 33 Call `assign_stack_local' to allocate a stack slot for a local variable. 34 This is usually done during the RTL generation for the function body, 35 but it can also be done in the reload pass when a pseudo-register does 36 not get a hard register. 37 38 Call `put_var_into_stack' when you learn, belatedly, that a variable 39 previously given a pseudo-register must in fact go in the stack. 40 This function changes the DECL_RTL to be a stack slot instead of a reg 41 then scans all the RTL instructions so far generated to correct them. */ 42 43 #include "config.h" 44 #include "system.h" 45 #include "coretypes.h" 46 #include "tm.h" 47 #include "rtl.h" 48 #include "tree.h" 49 #include "flags.h" 50 #include "except.h" 51 #include "function.h" 52 #include "expr.h" 53 #include "optabs.h" 54 #include "libfuncs.h" 55 #include "regs.h" 56 #include "hard-reg-set.h" 57 #include "insn-config.h" 58 #include "recog.h" 59 #include "output.h" 60 #include "basic-block.h" 61 #include "toplev.h" 62 #include "hashtab.h" 63 #include "ggc.h" 64 #include "tm_p.h" 65 #include "integrate.h" 66 #include "langhooks.h" 67 #include "target.h" 68 69 #ifndef TRAMPOLINE_ALIGNMENT 70 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY 71 #endif 72 73 #ifndef LOCAL_ALIGNMENT 74 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT 75 #endif 76 77 #ifndef STACK_ALIGNMENT_NEEDED 78 #define STACK_ALIGNMENT_NEEDED 1 79 #endif 80 81 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT) 82 83 /* Some systems use __main in a way incompatible with its use in gcc, in these 84 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to 85 give the same symbol without quotes for an alternative entry point. You 86 must define both, or neither. */ 87 #ifndef NAME__MAIN 88 #define NAME__MAIN "__main" 89 #endif 90 91 /* Round a value to the lowest integer less than it that is a multiple of 92 the required alignment. Avoid using division in case the value is 93 negative. Assume the alignment is a power of two. */ 94 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1)) 95 96 /* Similar, but round to the next highest integer that meets the 97 alignment. */ 98 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1)) 99 100 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp 101 during rtl generation. If they are different register numbers, this is 102 always true. It may also be true if 103 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl 104 generation. See fix_lexical_addr for details. */ 105 106 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM 107 #define NEED_SEPARATE_AP 108 #endif 109 110 /* Nonzero if function being compiled doesn't contain any calls 111 (ignoring the prologue and epilogue). This is set prior to 112 local register allocation and is valid for the remaining 113 compiler passes. */ 114 int current_function_is_leaf; 115 116 /* Nonzero if function being compiled doesn't contain any instructions 117 that can throw an exception. This is set prior to final. */ 118 119 int current_function_nothrow; 120 121 /* Nonzero if function being compiled doesn't modify the stack pointer 122 (ignoring the prologue and epilogue). This is only valid after 123 life_analysis has run. */ 124 int current_function_sp_is_unchanging; 125 126 /* Nonzero if the function being compiled is a leaf function which only 127 uses leaf registers. This is valid after reload (specifically after 128 sched2) and is useful only if the port defines LEAF_REGISTERS. */ 129 int current_function_uses_only_leaf_regs; 130 131 /* Nonzero once virtual register instantiation has been done. 132 assign_stack_local uses frame_pointer_rtx when this is nonzero. 133 calls.c:emit_library_call_value_1 uses it to set up 134 post-instantiation libcalls. */ 135 int virtuals_instantiated; 136 137 /* Nonzero if at least one trampoline has been created. */ 138 int trampolines_created; 139 140 /* Assign unique numbers to labels generated for profiling, debugging, etc. */ 141 static GTY(()) int funcdef_no; 142 143 /* These variables hold pointers to functions to create and destroy 144 target specific, per-function data structures. */ 145 struct machine_function * (*init_machine_status) (void); 146 147 /* The FUNCTION_DECL for an inline function currently being expanded. */ 148 tree inline_function_decl; 149 150 /* The currently compiled function. */ 151 struct function *cfun = 0; 152 153 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */ 154 static GTY(()) varray_type prologue; 155 static GTY(()) varray_type epilogue; 156 157 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue 158 in this function. */ 159 static GTY(()) varray_type sibcall_epilogue; 160 161 /* In order to evaluate some expressions, such as function calls returning 162 structures in memory, we need to temporarily allocate stack locations. 163 We record each allocated temporary in the following structure. 164 165 Associated with each temporary slot is a nesting level. When we pop up 166 one level, all temporaries associated with the previous level are freed. 167 Normally, all temporaries are freed after the execution of the statement 168 in which they were created. However, if we are inside a ({...}) grouping, 169 the result may be in a temporary and hence must be preserved. If the 170 result could be in a temporary, we preserve it if we can determine which 171 one it is in. If we cannot determine which temporary may contain the 172 result, all temporaries are preserved. A temporary is preserved by 173 pretending it was allocated at the previous nesting level. 174 175 Automatic variables are also assigned temporary slots, at the nesting 176 level where they are defined. They are marked a "kept" so that 177 free_temp_slots will not free them. */ 178 179 struct temp_slot GTY(()) 180 { 181 /* Points to next temporary slot. */ 182 struct temp_slot *next; 183 /* The rtx to used to reference the slot. */ 184 rtx slot; 185 /* The rtx used to represent the address if not the address of the 186 slot above. May be an EXPR_LIST if multiple addresses exist. */ 187 rtx address; 188 /* The alignment (in bits) of the slot. */ 189 unsigned int align; 190 /* The size, in units, of the slot. */ 191 HOST_WIDE_INT size; 192 /* The type of the object in the slot, or zero if it doesn't correspond 193 to a type. We use this to determine whether a slot can be reused. 194 It can be reused if objects of the type of the new slot will always 195 conflict with objects of the type of the old slot. */ 196 tree type; 197 /* The value of `sequence_rtl_expr' when this temporary is allocated. */ 198 tree rtl_expr; 199 /* Nonzero if this temporary is currently in use. */ 200 char in_use; 201 /* Nonzero if this temporary has its address taken. */ 202 char addr_taken; 203 /* Nesting level at which this slot is being used. */ 204 int level; 205 /* Nonzero if this should survive a call to free_temp_slots. */ 206 int keep; 207 /* The offset of the slot from the frame_pointer, including extra space 208 for alignment. This info is for combine_temp_slots. */ 209 HOST_WIDE_INT base_offset; 210 /* The size of the slot, including extra space for alignment. This 211 info is for combine_temp_slots. */ 212 HOST_WIDE_INT full_size; 213 }; 214 215 /* This structure is used to record MEMs or pseudos used to replace VAR, any 216 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to 217 maintain this list in case two operands of an insn were required to match; 218 in that case we must ensure we use the same replacement. */ 219 220 struct fixup_replacement GTY(()) 221 { 222 rtx old; 223 rtx new; 224 struct fixup_replacement *next; 225 }; 226 227 struct insns_for_mem_entry 228 { 229 /* A MEM. */ 230 rtx key; 231 /* These are the INSNs which reference the MEM. */ 232 rtx insns; 233 }; 234 235 /* Forward declarations. */ 236 237 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int, 238 struct function *); 239 static struct temp_slot *find_temp_slot_from_address (rtx); 240 static void put_reg_into_stack (struct function *, rtx, tree, enum machine_mode, 241 unsigned int, bool, bool, bool, htab_t); 242 static void schedule_fixup_var_refs (struct function *, rtx, tree, enum machine_mode, 243 htab_t); 244 static void fixup_var_refs (rtx, enum machine_mode, int, rtx, htab_t); 245 static struct fixup_replacement 246 *find_fixup_replacement (struct fixup_replacement **, rtx); 247 static void fixup_var_refs_insns (rtx, rtx, enum machine_mode, int, int, rtx); 248 static void fixup_var_refs_insns_with_hash (htab_t, rtx, enum machine_mode, int, rtx); 249 static void fixup_var_refs_insn (rtx, rtx, enum machine_mode, int, int, rtx); 250 static void fixup_var_refs_1 (rtx, enum machine_mode, rtx *, rtx, 251 struct fixup_replacement **, rtx); 252 static rtx fixup_memory_subreg (rtx, rtx, enum machine_mode, int); 253 static rtx walk_fixup_memory_subreg (rtx, rtx, enum machine_mode, int); 254 static rtx fixup_stack_1 (rtx, rtx); 255 static void optimize_bit_field (rtx, rtx, rtx *); 256 static void instantiate_decls (tree, int); 257 static void instantiate_decls_1 (tree, int); 258 static void instantiate_decl (rtx, HOST_WIDE_INT, int); 259 static rtx instantiate_new_reg (rtx, HOST_WIDE_INT *); 260 static int instantiate_virtual_regs_1 (rtx *, rtx, int); 261 static void delete_handlers (void); 262 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *); 263 static void pad_below (struct args_size *, enum machine_mode, tree); 264 static rtx round_trampoline_addr (rtx); 265 static rtx adjust_trampoline_addr (rtx); 266 static tree *identify_blocks_1 (rtx, tree *, tree *, tree *); 267 static void reorder_blocks_0 (tree); 268 static void reorder_blocks_1 (rtx, tree, varray_type *); 269 static void reorder_fix_fragments (tree); 270 static tree blocks_nreverse (tree); 271 static int all_blocks (tree, tree *); 272 static tree *get_block_vector (tree, int *); 273 extern tree debug_find_var_in_block_tree (tree, tree); 274 /* We always define `record_insns' even if its not used so that we 275 can always export `prologue_epilogue_contains'. */ 276 static void record_insns (rtx, varray_type *) ATTRIBUTE_UNUSED; 277 static int contains (rtx, varray_type); 278 #ifdef HAVE_return 279 static void emit_return_into_block (basic_block, rtx); 280 #endif 281 static void put_addressof_into_stack (rtx, htab_t); 282 static bool purge_addressof_1 (rtx *, rtx, int, int, int, htab_t); 283 static void purge_single_hard_subreg_set (rtx); 284 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX) 285 static rtx keep_stack_depressed (rtx); 286 #endif 287 static int is_addressof (rtx *, void *); 288 static hashval_t insns_for_mem_hash (const void *); 289 static int insns_for_mem_comp (const void *, const void *); 290 static int insns_for_mem_walk (rtx *, void *); 291 static void compute_insns_for_mem (rtx, rtx, htab_t); 292 static void prepare_function_start (tree); 293 static void do_clobber_return_reg (rtx, void *); 294 static void do_use_return_reg (rtx, void *); 295 static void instantiate_virtual_regs_lossage (rtx); 296 static tree split_complex_args (tree); 297 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED; 298 299 /* Pointer to chain of `struct function' for containing functions. */ 300 struct function *outer_function_chain; 301 302 /* List of insns that were postponed by purge_addressof_1. */ 303 static rtx postponed_insns; 304 305 /* Given a function decl for a containing function, 306 return the `struct function' for it. */ 307 308 struct function * 309 find_function_data (tree decl) 310 { 311 struct function *p; 312 313 for (p = outer_function_chain; p; p = p->outer) 314 if (p->decl == decl) 315 return p; 316 317 abort (); 318 } 319 320 /* Save the current context for compilation of a nested function. 321 This is called from language-specific code. The caller should use 322 the enter_nested langhook to save any language-specific state, 323 since this function knows only about language-independent 324 variables. */ 325 326 void 327 push_function_context_to (tree context) 328 { 329 struct function *p; 330 331 if (context) 332 { 333 if (context == current_function_decl) 334 cfun->contains_functions = 1; 335 else 336 { 337 struct function *containing = find_function_data (context); 338 containing->contains_functions = 1; 339 } 340 } 341 342 if (cfun == 0) 343 init_dummy_function_start (); 344 p = cfun; 345 346 p->outer = outer_function_chain; 347 outer_function_chain = p; 348 p->fixup_var_refs_queue = 0; 349 350 (*lang_hooks.function.enter_nested) (p); 351 352 cfun = 0; 353 } 354 355 void 356 push_function_context (void) 357 { 358 push_function_context_to (current_function_decl); 359 } 360 361 /* Restore the last saved context, at the end of a nested function. 362 This function is called from language-specific code. */ 363 364 void 365 pop_function_context_from (tree context ATTRIBUTE_UNUSED) 366 { 367 struct function *p = outer_function_chain; 368 struct var_refs_queue *queue; 369 370 cfun = p; 371 outer_function_chain = p->outer; 372 373 current_function_decl = p->decl; 374 reg_renumber = 0; 375 376 restore_emit_status (p); 377 378 (*lang_hooks.function.leave_nested) (p); 379 380 /* Finish doing put_var_into_stack for any of our variables which became 381 addressable during the nested function. If only one entry has to be 382 fixed up, just do that one. Otherwise, first make a list of MEMs that 383 are not to be unshared. */ 384 if (p->fixup_var_refs_queue == 0) 385 ; 386 else if (p->fixup_var_refs_queue->next == 0) 387 fixup_var_refs (p->fixup_var_refs_queue->modified, 388 p->fixup_var_refs_queue->promoted_mode, 389 p->fixup_var_refs_queue->unsignedp, 390 p->fixup_var_refs_queue->modified, 0); 391 else 392 { 393 rtx list = 0; 394 395 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next) 396 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list); 397 398 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next) 399 fixup_var_refs (queue->modified, queue->promoted_mode, 400 queue->unsignedp, list, 0); 401 402 } 403 404 p->fixup_var_refs_queue = 0; 405 406 /* Reset variables that have known state during rtx generation. */ 407 rtx_equal_function_value_matters = 1; 408 virtuals_instantiated = 0; 409 generating_concat_p = 1; 410 } 411 412 void 413 pop_function_context (void) 414 { 415 pop_function_context_from (current_function_decl); 416 } 417 418 /* Clear out all parts of the state in F that can safely be discarded 419 after the function has been parsed, but not compiled, to let 420 garbage collection reclaim the memory. */ 421 422 void 423 free_after_parsing (struct function *f) 424 { 425 /* f->expr->forced_labels is used by code generation. */ 426 /* f->emit->regno_reg_rtx is used by code generation. */ 427 /* f->varasm is used by code generation. */ 428 /* f->eh->eh_return_stub_label is used by code generation. */ 429 430 (*lang_hooks.function.final) (f); 431 f->stmt = NULL; 432 } 433 434 /* Clear out all parts of the state in F that can safely be discarded 435 after the function has been compiled, to let garbage collection 436 reclaim the memory. */ 437 438 void 439 free_after_compilation (struct function *f) 440 { 441 f->eh = NULL; 442 f->expr = NULL; 443 f->emit = NULL; 444 f->varasm = NULL; 445 f->machine = NULL; 446 447 f->x_temp_slots = NULL; 448 f->arg_offset_rtx = NULL; 449 f->return_rtx = NULL; 450 f->internal_arg_pointer = NULL; 451 f->x_nonlocal_labels = NULL; 452 f->x_nonlocal_goto_handler_slots = NULL; 453 f->x_nonlocal_goto_handler_labels = NULL; 454 f->x_nonlocal_goto_stack_level = NULL; 455 f->x_cleanup_label = NULL; 456 f->x_return_label = NULL; 457 f->x_naked_return_label = NULL; 458 f->computed_goto_common_label = NULL; 459 f->computed_goto_common_reg = NULL; 460 f->x_save_expr_regs = NULL; 461 f->x_stack_slot_list = NULL; 462 f->x_rtl_expr_chain = NULL; 463 f->x_tail_recursion_label = NULL; 464 f->x_tail_recursion_reentry = NULL; 465 f->x_arg_pointer_save_area = NULL; 466 f->x_clobber_return_insn = NULL; 467 f->x_context_display = NULL; 468 f->x_trampoline_list = NULL; 469 f->x_parm_birth_insn = NULL; 470 f->x_last_parm_insn = NULL; 471 f->x_parm_reg_stack_loc = NULL; 472 f->fixup_var_refs_queue = NULL; 473 f->original_arg_vector = NULL; 474 f->original_decl_initial = NULL; 475 f->inl_last_parm_insn = NULL; 476 f->epilogue_delay_list = NULL; 477 } 478 479 /* Allocate fixed slots in the stack frame of the current function. */ 480 481 /* Return size needed for stack frame based on slots so far allocated in 482 function F. 483 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY; 484 the caller may have to do that. */ 485 486 HOST_WIDE_INT 487 get_func_frame_size (struct function *f) 488 { 489 #ifdef FRAME_GROWS_DOWNWARD 490 return -f->x_frame_offset; 491 #else 492 return f->x_frame_offset; 493 #endif 494 } 495 496 /* Return size needed for stack frame based on slots so far allocated. 497 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY; 498 the caller may have to do that. */ 499 HOST_WIDE_INT 500 get_frame_size (void) 501 { 502 return get_func_frame_size (cfun); 503 } 504 505 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it 506 with machine mode MODE. 507 508 ALIGN controls the amount of alignment for the address of the slot: 509 0 means according to MODE, 510 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that, 511 -2 means use BITS_PER_UNIT, 512 positive specifies alignment boundary in bits. 513 514 We do not round to stack_boundary here. 515 516 FUNCTION specifies the function to allocate in. */ 517 518 static rtx 519 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align, 520 struct function *function) 521 { 522 rtx x, addr; 523 int bigend_correction = 0; 524 int alignment; 525 int frame_off, frame_alignment, frame_phase; 526 527 if (align == 0) 528 { 529 tree type; 530 531 if (mode == BLKmode) 532 alignment = BIGGEST_ALIGNMENT; 533 else 534 alignment = GET_MODE_ALIGNMENT (mode); 535 536 /* Allow the target to (possibly) increase the alignment of this 537 stack slot. */ 538 type = (*lang_hooks.types.type_for_mode) (mode, 0); 539 if (type) 540 alignment = LOCAL_ALIGNMENT (type, alignment); 541 542 alignment /= BITS_PER_UNIT; 543 } 544 else if (align == -1) 545 { 546 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT; 547 size = CEIL_ROUND (size, alignment); 548 } 549 else if (align == -2) 550 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */ 551 else 552 alignment = align / BITS_PER_UNIT; 553 554 #ifdef FRAME_GROWS_DOWNWARD 555 function->x_frame_offset -= size; 556 #endif 557 558 /* Ignore alignment we can't do with expected alignment of the boundary. */ 559 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY) 560 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT; 561 562 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT) 563 function->stack_alignment_needed = alignment * BITS_PER_UNIT; 564 565 /* Calculate how many bytes the start of local variables is off from 566 stack alignment. */ 567 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT; 568 frame_off = STARTING_FRAME_OFFSET % frame_alignment; 569 frame_phase = frame_off ? frame_alignment - frame_off : 0; 570 571 /* Round the frame offset to the specified alignment. The default is 572 to always honor requests to align the stack but a port may choose to 573 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */ 574 if (STACK_ALIGNMENT_NEEDED 575 || mode != BLKmode 576 || size != 0) 577 { 578 /* We must be careful here, since FRAME_OFFSET might be negative and 579 division with a negative dividend isn't as well defined as we might 580 like. So we instead assume that ALIGNMENT is a power of two and 581 use logical operations which are unambiguous. */ 582 #ifdef FRAME_GROWS_DOWNWARD 583 function->x_frame_offset 584 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment) 585 + frame_phase); 586 #else 587 function->x_frame_offset 588 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment) 589 + frame_phase); 590 #endif 591 } 592 593 /* On a big-endian machine, if we are allocating more space than we will use, 594 use the least significant bytes of those that are allocated. */ 595 if (BYTES_BIG_ENDIAN && mode != BLKmode) 596 bigend_correction = size - GET_MODE_SIZE (mode); 597 598 /* If we have already instantiated virtual registers, return the actual 599 address relative to the frame pointer. */ 600 if (function == cfun && virtuals_instantiated) 601 addr = plus_constant (frame_pointer_rtx, 602 trunc_int_for_mode 603 (frame_offset + bigend_correction 604 + STARTING_FRAME_OFFSET, Pmode)); 605 else 606 addr = plus_constant (virtual_stack_vars_rtx, 607 trunc_int_for_mode 608 (function->x_frame_offset + bigend_correction, 609 Pmode)); 610 611 #ifndef FRAME_GROWS_DOWNWARD 612 function->x_frame_offset += size; 613 #endif 614 615 x = gen_rtx_MEM (mode, addr); 616 617 function->x_stack_slot_list 618 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list); 619 620 return x; 621 } 622 623 /* Wrapper around assign_stack_local_1; assign a local stack slot for the 624 current function. */ 625 626 rtx 627 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align) 628 { 629 return assign_stack_local_1 (mode, size, align, cfun); 630 } 631 632 /* Allocate a temporary stack slot and record it for possible later 633 reuse. 634 635 MODE is the machine mode to be given to the returned rtx. 636 637 SIZE is the size in units of the space required. We do no rounding here 638 since assign_stack_local will do any required rounding. 639 640 KEEP is 1 if this slot is to be retained after a call to 641 free_temp_slots. Automatic variables for a block are allocated 642 with this flag. KEEP is 2 if we allocate a longer term temporary, 643 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3 644 if we are to allocate something at an inner level to be treated as 645 a variable in the block (e.g., a SAVE_EXPR). 646 647 TYPE is the type that will be used for the stack slot. */ 648 649 rtx 650 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, int keep, 651 tree type) 652 { 653 unsigned int align; 654 struct temp_slot *p, *best_p = 0; 655 rtx slot; 656 657 /* If SIZE is -1 it means that somebody tried to allocate a temporary 658 of a variable size. */ 659 if (size == -1) 660 abort (); 661 662 if (mode == BLKmode) 663 align = BIGGEST_ALIGNMENT; 664 else 665 align = GET_MODE_ALIGNMENT (mode); 666 667 if (! type) 668 type = (*lang_hooks.types.type_for_mode) (mode, 0); 669 670 if (type) 671 align = LOCAL_ALIGNMENT (type, align); 672 673 /* Try to find an available, already-allocated temporary of the proper 674 mode which meets the size and alignment requirements. Choose the 675 smallest one with the closest alignment. */ 676 for (p = temp_slots; p; p = p->next) 677 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode 678 && ! p->in_use 679 && objects_must_conflict_p (p->type, type) 680 && (best_p == 0 || best_p->size > p->size 681 || (best_p->size == p->size && best_p->align > p->align))) 682 { 683 if (p->align == align && p->size == size) 684 { 685 best_p = 0; 686 break; 687 } 688 best_p = p; 689 } 690 691 /* Make our best, if any, the one to use. */ 692 if (best_p) 693 { 694 /* If there are enough aligned bytes left over, make them into a new 695 temp_slot so that the extra bytes don't get wasted. Do this only 696 for BLKmode slots, so that we can be sure of the alignment. */ 697 if (GET_MODE (best_p->slot) == BLKmode) 698 { 699 int alignment = best_p->align / BITS_PER_UNIT; 700 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment); 701 702 if (best_p->size - rounded_size >= alignment) 703 { 704 p = ggc_alloc (sizeof (struct temp_slot)); 705 p->in_use = p->addr_taken = 0; 706 p->size = best_p->size - rounded_size; 707 p->base_offset = best_p->base_offset + rounded_size; 708 p->full_size = best_p->full_size - rounded_size; 709 p->slot = gen_rtx_MEM (BLKmode, 710 plus_constant (XEXP (best_p->slot, 0), 711 rounded_size)); 712 p->align = best_p->align; 713 p->address = 0; 714 p->rtl_expr = 0; 715 p->type = best_p->type; 716 p->next = temp_slots; 717 temp_slots = p; 718 719 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot, 720 stack_slot_list); 721 722 best_p->size = rounded_size; 723 best_p->full_size = rounded_size; 724 } 725 } 726 727 p = best_p; 728 } 729 730 /* If we still didn't find one, make a new temporary. */ 731 if (p == 0) 732 { 733 HOST_WIDE_INT frame_offset_old = frame_offset; 734 735 p = ggc_alloc (sizeof (struct temp_slot)); 736 737 /* We are passing an explicit alignment request to assign_stack_local. 738 One side effect of that is assign_stack_local will not round SIZE 739 to ensure the frame offset remains suitably aligned. 740 741 So for requests which depended on the rounding of SIZE, we go ahead 742 and round it now. We also make sure ALIGNMENT is at least 743 BIGGEST_ALIGNMENT. */ 744 if (mode == BLKmode && align < BIGGEST_ALIGNMENT) 745 abort (); 746 p->slot = assign_stack_local (mode, 747 (mode == BLKmode 748 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT) 749 : size), 750 align); 751 752 p->align = align; 753 754 /* The following slot size computation is necessary because we don't 755 know the actual size of the temporary slot until assign_stack_local 756 has performed all the frame alignment and size rounding for the 757 requested temporary. Note that extra space added for alignment 758 can be either above or below this stack slot depending on which 759 way the frame grows. We include the extra space if and only if it 760 is above this slot. */ 761 #ifdef FRAME_GROWS_DOWNWARD 762 p->size = frame_offset_old - frame_offset; 763 #else 764 p->size = size; 765 #endif 766 767 /* Now define the fields used by combine_temp_slots. */ 768 #ifdef FRAME_GROWS_DOWNWARD 769 p->base_offset = frame_offset; 770 p->full_size = frame_offset_old - frame_offset; 771 #else 772 p->base_offset = frame_offset_old; 773 p->full_size = frame_offset - frame_offset_old; 774 #endif 775 p->address = 0; 776 p->next = temp_slots; 777 temp_slots = p; 778 } 779 780 p->in_use = 1; 781 p->addr_taken = 0; 782 p->rtl_expr = seq_rtl_expr; 783 p->type = type; 784 785 if (keep == 2) 786 { 787 p->level = target_temp_slot_level; 788 p->keep = 1; 789 } 790 else if (keep == 3) 791 { 792 p->level = var_temp_slot_level; 793 p->keep = 0; 794 } 795 else 796 { 797 p->level = temp_slot_level; 798 p->keep = keep; 799 } 800 801 802 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */ 803 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0)); 804 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list); 805 806 /* If we know the alias set for the memory that will be used, use 807 it. If there's no TYPE, then we don't know anything about the 808 alias set for the memory. */ 809 set_mem_alias_set (slot, type ? get_alias_set (type) : 0); 810 set_mem_align (slot, align); 811 812 /* If a type is specified, set the relevant flags. */ 813 if (type != 0) 814 { 815 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly 816 && TYPE_READONLY (type)); 817 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type); 818 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type)); 819 } 820 821 return slot; 822 } 823 824 /* Allocate a temporary stack slot and record it for possible later 825 reuse. First three arguments are same as in preceding function. */ 826 827 rtx 828 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep) 829 { 830 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE); 831 } 832 833 /* Assign a temporary. 834 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl 835 and so that should be used in error messages. In either case, we 836 allocate of the given type. 837 KEEP is as for assign_stack_temp. 838 MEMORY_REQUIRED is 1 if the result must be addressable stack memory; 839 it is 0 if a register is OK. 840 DONT_PROMOTE is 1 if we should not promote values in register 841 to wider modes. */ 842 843 rtx 844 assign_temp (tree type_or_decl, int keep, int memory_required, 845 int dont_promote ATTRIBUTE_UNUSED) 846 { 847 tree type, decl; 848 enum machine_mode mode; 849 #ifndef PROMOTE_FOR_CALL_ONLY 850 int unsignedp; 851 #endif 852 853 if (DECL_P (type_or_decl)) 854 decl = type_or_decl, type = TREE_TYPE (decl); 855 else 856 decl = NULL, type = type_or_decl; 857 858 mode = TYPE_MODE (type); 859 #ifndef PROMOTE_FOR_CALL_ONLY 860 unsignedp = TREE_UNSIGNED (type); 861 #endif 862 863 if (mode == BLKmode || memory_required) 864 { 865 HOST_WIDE_INT size = int_size_in_bytes (type); 866 rtx tmp; 867 868 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid 869 problems with allocating the stack space. */ 870 if (size == 0) 871 size = 1; 872 873 /* Unfortunately, we don't yet know how to allocate variable-sized 874 temporaries. However, sometimes we have a fixed upper limit on 875 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that 876 instead. This is the case for Chill variable-sized strings. */ 877 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE 878 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE 879 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1)) 880 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1); 881 882 /* The size of the temporary may be too large to fit into an integer. */ 883 /* ??? Not sure this should happen except for user silliness, so limit 884 this to things that aren't compiler-generated temporaries. The 885 rest of the time we'll abort in assign_stack_temp_for_type. */ 886 if (decl && size == -1 887 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST) 888 { 889 error ("%Jsize of variable '%D' is too large", decl, decl); 890 size = 1; 891 } 892 893 tmp = assign_stack_temp_for_type (mode, size, keep, type); 894 return tmp; 895 } 896 897 #ifndef PROMOTE_FOR_CALL_ONLY 898 if (! dont_promote) 899 mode = promote_mode (type, mode, &unsignedp, 0); 900 #endif 901 902 return gen_reg_rtx (mode); 903 } 904 905 /* Combine temporary stack slots which are adjacent on the stack. 906 907 This allows for better use of already allocated stack space. This is only 908 done for BLKmode slots because we can be sure that we won't have alignment 909 problems in this case. */ 910 911 void 912 combine_temp_slots (void) 913 { 914 struct temp_slot *p, *q; 915 struct temp_slot *prev_p, *prev_q; 916 int num_slots; 917 918 /* We can't combine slots, because the information about which slot 919 is in which alias set will be lost. */ 920 if (flag_strict_aliasing) 921 return; 922 923 /* If there are a lot of temp slots, don't do anything unless 924 high levels of optimization. */ 925 if (! flag_expensive_optimizations) 926 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++) 927 if (num_slots > 100 || (num_slots > 10 && optimize == 0)) 928 return; 929 930 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots) 931 { 932 int delete_p = 0; 933 934 if (! p->in_use && GET_MODE (p->slot) == BLKmode) 935 for (q = p->next, prev_q = p; q; q = prev_q->next) 936 { 937 int delete_q = 0; 938 if (! q->in_use && GET_MODE (q->slot) == BLKmode) 939 { 940 if (p->base_offset + p->full_size == q->base_offset) 941 { 942 /* Q comes after P; combine Q into P. */ 943 p->size += q->size; 944 p->full_size += q->full_size; 945 delete_q = 1; 946 } 947 else if (q->base_offset + q->full_size == p->base_offset) 948 { 949 /* P comes after Q; combine P into Q. */ 950 q->size += p->size; 951 q->full_size += p->full_size; 952 delete_p = 1; 953 break; 954 } 955 } 956 /* Either delete Q or advance past it. */ 957 if (delete_q) 958 prev_q->next = q->next; 959 else 960 prev_q = q; 961 } 962 /* Either delete P or advance past it. */ 963 if (delete_p) 964 { 965 if (prev_p) 966 prev_p->next = p->next; 967 else 968 temp_slots = p->next; 969 } 970 else 971 prev_p = p; 972 } 973 } 974 975 /* Find the temp slot corresponding to the object at address X. */ 976 977 static struct temp_slot * 978 find_temp_slot_from_address (rtx x) 979 { 980 struct temp_slot *p; 981 rtx next; 982 983 for (p = temp_slots; p; p = p->next) 984 { 985 if (! p->in_use) 986 continue; 987 988 else if (XEXP (p->slot, 0) == x 989 || p->address == x 990 || (GET_CODE (x) == PLUS 991 && XEXP (x, 0) == virtual_stack_vars_rtx 992 && GET_CODE (XEXP (x, 1)) == CONST_INT 993 && INTVAL (XEXP (x, 1)) >= p->base_offset 994 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)) 995 return p; 996 997 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST) 998 for (next = p->address; next; next = XEXP (next, 1)) 999 if (XEXP (next, 0) == x) 1000 return p; 1001 } 1002 1003 /* If we have a sum involving a register, see if it points to a temp 1004 slot. */ 1005 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG 1006 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0) 1007 return p; 1008 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG 1009 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0) 1010 return p; 1011 1012 return 0; 1013 } 1014 1015 /* Indicate that NEW is an alternate way of referring to the temp slot 1016 that previously was known by OLD. */ 1017 1018 void 1019 update_temp_slot_address (rtx old, rtx new) 1020 { 1021 struct temp_slot *p; 1022 1023 if (rtx_equal_p (old, new)) 1024 return; 1025 1026 p = find_temp_slot_from_address (old); 1027 1028 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW 1029 is a register, see if one operand of the PLUS is a temporary 1030 location. If so, NEW points into it. Otherwise, if both OLD and 1031 NEW are a PLUS and if there is a register in common between them. 1032 If so, try a recursive call on those values. */ 1033 if (p == 0) 1034 { 1035 if (GET_CODE (old) != PLUS) 1036 return; 1037 1038 if (GET_CODE (new) == REG) 1039 { 1040 update_temp_slot_address (XEXP (old, 0), new); 1041 update_temp_slot_address (XEXP (old, 1), new); 1042 return; 1043 } 1044 else if (GET_CODE (new) != PLUS) 1045 return; 1046 1047 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0))) 1048 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1)); 1049 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0))) 1050 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1)); 1051 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1))) 1052 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0)); 1053 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1))) 1054 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0)); 1055 1056 return; 1057 } 1058 1059 /* Otherwise add an alias for the temp's address. */ 1060 else if (p->address == 0) 1061 p->address = new; 1062 else 1063 { 1064 if (GET_CODE (p->address) != EXPR_LIST) 1065 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX); 1066 1067 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address); 1068 } 1069 } 1070 1071 /* If X could be a reference to a temporary slot, mark the fact that its 1072 address was taken. */ 1073 1074 void 1075 mark_temp_addr_taken (rtx x) 1076 { 1077 struct temp_slot *p; 1078 1079 if (x == 0) 1080 return; 1081 1082 /* If X is not in memory or is at a constant address, it cannot be in 1083 a temporary slot. */ 1084 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))) 1085 return; 1086 1087 p = find_temp_slot_from_address (XEXP (x, 0)); 1088 if (p != 0) 1089 p->addr_taken = 1; 1090 } 1091 1092 /* If X could be a reference to a temporary slot, mark that slot as 1093 belonging to the to one level higher than the current level. If X 1094 matched one of our slots, just mark that one. Otherwise, we can't 1095 easily predict which it is, so upgrade all of them. Kept slots 1096 need not be touched. 1097 1098 This is called when an ({...}) construct occurs and a statement 1099 returns a value in memory. */ 1100 1101 void 1102 preserve_temp_slots (rtx x) 1103 { 1104 struct temp_slot *p = 0; 1105 1106 /* If there is no result, we still might have some objects whose address 1107 were taken, so we need to make sure they stay around. */ 1108 if (x == 0) 1109 { 1110 for (p = temp_slots; p; p = p->next) 1111 if (p->in_use && p->level == temp_slot_level && p->addr_taken) 1112 p->level--; 1113 1114 return; 1115 } 1116 1117 /* If X is a register that is being used as a pointer, see if we have 1118 a temporary slot we know it points to. To be consistent with 1119 the code below, we really should preserve all non-kept slots 1120 if we can't find a match, but that seems to be much too costly. */ 1121 if (GET_CODE (x) == REG && REG_POINTER (x)) 1122 p = find_temp_slot_from_address (x); 1123 1124 /* If X is not in memory or is at a constant address, it cannot be in 1125 a temporary slot, but it can contain something whose address was 1126 taken. */ 1127 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))) 1128 { 1129 for (p = temp_slots; p; p = p->next) 1130 if (p->in_use && p->level == temp_slot_level && p->addr_taken) 1131 p->level--; 1132 1133 return; 1134 } 1135 1136 /* First see if we can find a match. */ 1137 if (p == 0) 1138 p = find_temp_slot_from_address (XEXP (x, 0)); 1139 1140 if (p != 0) 1141 { 1142 /* Move everything at our level whose address was taken to our new 1143 level in case we used its address. */ 1144 struct temp_slot *q; 1145 1146 if (p->level == temp_slot_level) 1147 { 1148 for (q = temp_slots; q; q = q->next) 1149 if (q != p && q->addr_taken && q->level == p->level) 1150 q->level--; 1151 1152 p->level--; 1153 p->addr_taken = 0; 1154 } 1155 return; 1156 } 1157 1158 /* Otherwise, preserve all non-kept slots at this level. */ 1159 for (p = temp_slots; p; p = p->next) 1160 if (p->in_use && p->level == temp_slot_level && ! p->keep) 1161 p->level--; 1162 } 1163 1164 /* X is the result of an RTL_EXPR. If it is a temporary slot associated 1165 with that RTL_EXPR, promote it into a temporary slot at the present 1166 level so it will not be freed when we free slots made in the 1167 RTL_EXPR. */ 1168 1169 void 1170 preserve_rtl_expr_result (rtx x) 1171 { 1172 struct temp_slot *p; 1173 1174 /* If X is not in memory or is at a constant address, it cannot be in 1175 a temporary slot. */ 1176 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))) 1177 return; 1178 1179 /* If we can find a match, move it to our level unless it is already at 1180 an upper level. */ 1181 p = find_temp_slot_from_address (XEXP (x, 0)); 1182 if (p != 0) 1183 { 1184 p->level = MIN (p->level, temp_slot_level); 1185 p->rtl_expr = 0; 1186 } 1187 1188 return; 1189 } 1190 1191 /* Free all temporaries used so far. This is normally called at the end 1192 of generating code for a statement. Don't free any temporaries 1193 currently in use for an RTL_EXPR that hasn't yet been emitted. 1194 We could eventually do better than this since it can be reused while 1195 generating the same RTL_EXPR, but this is complex and probably not 1196 worthwhile. */ 1197 1198 void 1199 free_temp_slots (void) 1200 { 1201 struct temp_slot *p; 1202 1203 for (p = temp_slots; p; p = p->next) 1204 if (p->in_use && p->level == temp_slot_level && ! p->keep 1205 && p->rtl_expr == 0) 1206 p->in_use = 0; 1207 1208 combine_temp_slots (); 1209 } 1210 1211 /* Free all temporary slots used in T, an RTL_EXPR node. */ 1212 1213 void 1214 free_temps_for_rtl_expr (tree t) 1215 { 1216 struct temp_slot *p; 1217 1218 for (p = temp_slots; p; p = p->next) 1219 if (p->rtl_expr == t) 1220 { 1221 /* If this slot is below the current TEMP_SLOT_LEVEL, then it 1222 needs to be preserved. This can happen if a temporary in 1223 the RTL_EXPR was addressed; preserve_temp_slots will move 1224 the temporary into a higher level. */ 1225 if (temp_slot_level <= p->level) 1226 p->in_use = 0; 1227 else 1228 p->rtl_expr = NULL_TREE; 1229 } 1230 1231 combine_temp_slots (); 1232 } 1233 1234 /* Mark all temporaries ever allocated in this function as not suitable 1235 for reuse until the current level is exited. */ 1236 1237 void 1238 mark_all_temps_used (void) 1239 { 1240 struct temp_slot *p; 1241 1242 for (p = temp_slots; p; p = p->next) 1243 { 1244 p->in_use = p->keep = 1; 1245 p->level = MIN (p->level, temp_slot_level); 1246 } 1247 } 1248 1249 /* Push deeper into the nesting level for stack temporaries. */ 1250 1251 void 1252 push_temp_slots (void) 1253 { 1254 temp_slot_level++; 1255 } 1256 1257 /* Pop a temporary nesting level. All slots in use in the current level 1258 are freed. */ 1259 1260 void 1261 pop_temp_slots (void) 1262 { 1263 struct temp_slot *p; 1264 1265 for (p = temp_slots; p; p = p->next) 1266 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0) 1267 p->in_use = 0; 1268 1269 combine_temp_slots (); 1270 1271 temp_slot_level--; 1272 } 1273 1274 /* Initialize temporary slots. */ 1275 1276 void 1277 init_temp_slots (void) 1278 { 1279 /* We have not allocated any temporaries yet. */ 1280 temp_slots = 0; 1281 temp_slot_level = 0; 1282 var_temp_slot_level = 0; 1283 target_temp_slot_level = 0; 1284 } 1285 1286 /* Retroactively move an auto variable from a register to a stack 1287 slot. This is done when an address-reference to the variable is 1288 seen. If RESCAN is true, all previously emitted instructions are 1289 examined and modified to handle the fact that DECL is now 1290 addressable. */ 1291 1292 void 1293 put_var_into_stack (tree decl, int rescan) 1294 { 1295 rtx reg; 1296 enum machine_mode promoted_mode, decl_mode; 1297 struct function *function = 0; 1298 tree context; 1299 bool can_use_addressof_p; 1300 bool volatile_p = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl); 1301 bool used_p = (TREE_USED (decl) 1302 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0)); 1303 1304 context = decl_function_context (decl); 1305 1306 /* Get the current rtl used for this object and its original mode. */ 1307 reg = (TREE_CODE (decl) == SAVE_EXPR 1308 ? SAVE_EXPR_RTL (decl) 1309 : DECL_RTL_IF_SET (decl)); 1310 1311 /* No need to do anything if decl has no rtx yet 1312 since in that case caller is setting TREE_ADDRESSABLE 1313 and a stack slot will be assigned when the rtl is made. */ 1314 if (reg == 0) 1315 return; 1316 1317 /* Get the declared mode for this object. */ 1318 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl)) 1319 : DECL_MODE (decl)); 1320 /* Get the mode it's actually stored in. */ 1321 promoted_mode = GET_MODE (reg); 1322 1323 /* If this variable comes from an outer function, find that 1324 function's saved context. Don't use find_function_data here, 1325 because it might not be in any active function. 1326 FIXME: Is that really supposed to happen? 1327 It does in ObjC at least. */ 1328 if (context != current_function_decl && context != inline_function_decl) 1329 for (function = outer_function_chain; function; function = function->outer) 1330 if (function->decl == context) 1331 break; 1332 1333 /* If this is a variable-sized object or a structure passed by invisible 1334 reference, with a pseudo to address it, put that pseudo into the stack 1335 if the var is non-local. */ 1336 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl) 1337 && GET_CODE (reg) == MEM 1338 && GET_CODE (XEXP (reg, 0)) == REG 1339 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER) 1340 { 1341 reg = XEXP (reg, 0); 1342 decl_mode = promoted_mode = GET_MODE (reg); 1343 } 1344 1345 /* If this variable lives in the current function and we don't need to put it 1346 in the stack for the sake of setjmp or the non-locality, try to keep it in 1347 a register until we know we actually need the address. */ 1348 can_use_addressof_p 1349 = (function == 0 1350 && ! (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)) 1351 && optimize > 0 1352 /* FIXME make it work for promoted modes too */ 1353 && decl_mode == promoted_mode 1354 #ifdef NON_SAVING_SETJMP 1355 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp) 1356 #endif 1357 ); 1358 1359 /* If we can't use ADDRESSOF, make sure we see through one we already 1360 generated. */ 1361 if (! can_use_addressof_p 1362 && GET_CODE (reg) == MEM 1363 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF) 1364 reg = XEXP (XEXP (reg, 0), 0); 1365 1366 /* Now we should have a value that resides in one or more pseudo regs. */ 1367 1368 if (GET_CODE (reg) == REG) 1369 { 1370 if (can_use_addressof_p) 1371 gen_mem_addressof (reg, decl, rescan); 1372 else 1373 put_reg_into_stack (function, reg, TREE_TYPE (decl), decl_mode, 1374 0, volatile_p, used_p, false, 0); 1375 } 1376 else if (GET_CODE (reg) == CONCAT) 1377 { 1378 /* A CONCAT contains two pseudos; put them both in the stack. 1379 We do it so they end up consecutive. 1380 We fixup references to the parts only after we fixup references 1381 to the whole CONCAT, lest we do double fixups for the latter 1382 references. */ 1383 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0)); 1384 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0); 1385 rtx lopart = XEXP (reg, 0); 1386 rtx hipart = XEXP (reg, 1); 1387 #ifdef FRAME_GROWS_DOWNWARD 1388 /* Since part 0 should have a lower address, do it second. */ 1389 put_reg_into_stack (function, hipart, part_type, part_mode, 1390 0, volatile_p, false, false, 0); 1391 put_reg_into_stack (function, lopart, part_type, part_mode, 1392 0, volatile_p, false, true, 0); 1393 #else 1394 put_reg_into_stack (function, lopart, part_type, part_mode, 1395 0, volatile_p, false, false, 0); 1396 put_reg_into_stack (function, hipart, part_type, part_mode, 1397 0, volatile_p, false, true, 0); 1398 #endif 1399 1400 /* Change the CONCAT into a combined MEM for both parts. */ 1401 PUT_CODE (reg, MEM); 1402 MEM_ATTRS (reg) = 0; 1403 1404 /* set_mem_attributes uses DECL_RTL to avoid re-generating of 1405 already computed alias sets. Here we want to re-generate. */ 1406 if (DECL_P (decl)) 1407 SET_DECL_RTL (decl, NULL); 1408 set_mem_attributes (reg, decl, 1); 1409 if (DECL_P (decl)) 1410 SET_DECL_RTL (decl, reg); 1411 1412 /* The two parts are in memory order already. 1413 Use the lower parts address as ours. */ 1414 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0); 1415 /* Prevent sharing of rtl that might lose. */ 1416 if (GET_CODE (XEXP (reg, 0)) == PLUS) 1417 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0)); 1418 if (used_p && rescan) 1419 { 1420 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl), 1421 promoted_mode, 0); 1422 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0); 1423 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0); 1424 } 1425 } 1426 else 1427 return; 1428 } 1429 1430 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG 1431 into the stack frame of FUNCTION (0 means the current function). 1432 TYPE is the user-level data type of the value hold in the register. 1433 DECL_MODE is the machine mode of the user-level data type. 1434 ORIGINAL_REGNO must be set if the real regno is not visible in REG. 1435 VOLATILE_P is true if this is for a "volatile" decl. 1436 USED_P is true if this reg might have already been used in an insn. 1437 CONSECUTIVE_P is true if the stack slot assigned to reg must be 1438 consecutive with the previous stack slot. */ 1439 1440 static void 1441 put_reg_into_stack (struct function *function, rtx reg, tree type, 1442 enum machine_mode decl_mode, unsigned int original_regno, 1443 bool volatile_p, bool used_p, bool consecutive_p, 1444 htab_t ht) 1445 { 1446 struct function *func = function ? function : cfun; 1447 enum machine_mode mode = GET_MODE (reg); 1448 unsigned int regno = original_regno; 1449 rtx new = 0; 1450 1451 if (regno == 0) 1452 regno = REGNO (reg); 1453 1454 if (regno < func->x_max_parm_reg) 1455 { 1456 if (!func->x_parm_reg_stack_loc) 1457 abort (); 1458 new = func->x_parm_reg_stack_loc[regno]; 1459 } 1460 1461 if (new == 0) 1462 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 1463 consecutive_p ? -2 : 0, func); 1464 1465 PUT_CODE (reg, MEM); 1466 PUT_MODE (reg, decl_mode); 1467 XEXP (reg, 0) = XEXP (new, 0); 1468 MEM_ATTRS (reg) = 0; 1469 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */ 1470 MEM_VOLATILE_P (reg) = volatile_p; 1471 1472 /* If this is a memory ref that contains aggregate components, 1473 mark it as such for cse and loop optimize. If we are reusing a 1474 previously generated stack slot, then we need to copy the bit in 1475 case it was set for other reasons. For instance, it is set for 1476 __builtin_va_alist. */ 1477 if (type) 1478 { 1479 MEM_SET_IN_STRUCT_P (reg, 1480 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new)); 1481 set_mem_alias_set (reg, get_alias_set (type)); 1482 } 1483 1484 if (used_p) 1485 schedule_fixup_var_refs (function, reg, type, mode, ht); 1486 } 1487 1488 /* Make sure that all refs to the variable, previously made 1489 when it was a register, are fixed up to be valid again. 1490 See function above for meaning of arguments. */ 1491 1492 static void 1493 schedule_fixup_var_refs (struct function *function, rtx reg, tree type, 1494 enum machine_mode promoted_mode, htab_t ht) 1495 { 1496 int unsigned_p = type ? TREE_UNSIGNED (type) : 0; 1497 1498 if (function != 0) 1499 { 1500 struct var_refs_queue *temp; 1501 1502 temp = ggc_alloc (sizeof (struct var_refs_queue)); 1503 temp->modified = reg; 1504 temp->promoted_mode = promoted_mode; 1505 temp->unsignedp = unsigned_p; 1506 temp->next = function->fixup_var_refs_queue; 1507 function->fixup_var_refs_queue = temp; 1508 } 1509 else 1510 /* Variable is local; fix it up now. */ 1511 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht); 1512 } 1513 1514 static void 1515 fixup_var_refs (rtx var, enum machine_mode promoted_mode, int unsignedp, 1516 rtx may_share, htab_t ht) 1517 { 1518 tree pending; 1519 rtx first_insn = get_insns (); 1520 struct sequence_stack *stack = seq_stack; 1521 tree rtl_exps = rtl_expr_chain; 1522 1523 /* If there's a hash table, it must record all uses of VAR. */ 1524 if (ht) 1525 { 1526 if (stack != 0) 1527 abort (); 1528 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp, 1529 may_share); 1530 return; 1531 } 1532 1533 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp, 1534 stack == 0, may_share); 1535 1536 /* Scan all pending sequences too. */ 1537 for (; stack; stack = stack->next) 1538 { 1539 push_to_full_sequence (stack->first, stack->last); 1540 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp, 1541 stack->next != 0, may_share); 1542 /* Update remembered end of sequence 1543 in case we added an insn at the end. */ 1544 stack->last = get_last_insn (); 1545 end_sequence (); 1546 } 1547 1548 /* Scan all waiting RTL_EXPRs too. */ 1549 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending)) 1550 { 1551 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending)); 1552 if (seq != const0_rtx && seq != 0) 1553 { 1554 push_to_sequence (seq); 1555 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0, 1556 may_share); 1557 end_sequence (); 1558 } 1559 } 1560 } 1561 1562 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is 1563 some part of an insn. Return a struct fixup_replacement whose OLD 1564 value is equal to X. Allocate a new structure if no such entry exists. */ 1565 1566 static struct fixup_replacement * 1567 find_fixup_replacement (struct fixup_replacement **replacements, rtx x) 1568 { 1569 struct fixup_replacement *p; 1570 1571 /* See if we have already replaced this. */ 1572 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next) 1573 ; 1574 1575 if (p == 0) 1576 { 1577 p = xmalloc (sizeof (struct fixup_replacement)); 1578 p->old = x; 1579 p->new = 0; 1580 p->next = *replacements; 1581 *replacements = p; 1582 } 1583 1584 return p; 1585 } 1586 1587 /* Scan the insn-chain starting with INSN for refs to VAR and fix them 1588 up. TOPLEVEL is nonzero if this chain is the main chain of insns 1589 for the current function. MAY_SHARE is either a MEM that is not 1590 to be unshared or a list of them. */ 1591 1592 static void 1593 fixup_var_refs_insns (rtx insn, rtx var, enum machine_mode promoted_mode, 1594 int unsignedp, int toplevel, rtx may_share) 1595 { 1596 while (insn) 1597 { 1598 /* fixup_var_refs_insn might modify insn, so save its next 1599 pointer now. */ 1600 rtx next = NEXT_INSN (insn); 1601 1602 /* CALL_PLACEHOLDERs are special; we have to switch into each of 1603 the three sequences they (potentially) contain, and process 1604 them recursively. The CALL_INSN itself is not interesting. */ 1605 1606 if (GET_CODE (insn) == CALL_INSN 1607 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER) 1608 { 1609 int i; 1610 1611 /* Look at the Normal call, sibling call and tail recursion 1612 sequences attached to the CALL_PLACEHOLDER. */ 1613 for (i = 0; i < 3; i++) 1614 { 1615 rtx seq = XEXP (PATTERN (insn), i); 1616 if (seq) 1617 { 1618 push_to_sequence (seq); 1619 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0, 1620 may_share); 1621 XEXP (PATTERN (insn), i) = get_insns (); 1622 end_sequence (); 1623 } 1624 } 1625 } 1626 1627 else if (INSN_P (insn)) 1628 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel, 1629 may_share); 1630 1631 insn = next; 1632 } 1633 } 1634 1635 /* Look up the insns which reference VAR in HT and fix them up. Other 1636 arguments are the same as fixup_var_refs_insns. 1637 1638 N.B. No need for special processing of CALL_PLACEHOLDERs here, 1639 because the hash table will point straight to the interesting insn 1640 (inside the CALL_PLACEHOLDER). */ 1641 1642 static void 1643 fixup_var_refs_insns_with_hash (htab_t ht, rtx var, enum machine_mode promoted_mode, 1644 int unsignedp, rtx may_share) 1645 { 1646 struct insns_for_mem_entry tmp; 1647 struct insns_for_mem_entry *ime; 1648 rtx insn_list; 1649 1650 tmp.key = var; 1651 ime = htab_find (ht, &tmp); 1652 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1)) 1653 if (INSN_P (XEXP (insn_list, 0)) && !INSN_DELETED_P (XEXP (insn_list, 0))) 1654 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode, 1655 unsignedp, 1, may_share); 1656 } 1657 1658 1659 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is 1660 the insn under examination, VAR is the variable to fix up 1661 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and 1662 TOPLEVEL is nonzero if this is the main insn chain for this 1663 function. */ 1664 1665 static void 1666 fixup_var_refs_insn (rtx insn, rtx var, enum machine_mode promoted_mode, 1667 int unsignedp, int toplevel, rtx no_share) 1668 { 1669 rtx call_dest = 0; 1670 rtx set, prev, prev_set; 1671 rtx note; 1672 1673 /* Remember the notes in case we delete the insn. */ 1674 note = REG_NOTES (insn); 1675 1676 /* If this is a CLOBBER of VAR, delete it. 1677 1678 If it has a REG_LIBCALL note, delete the REG_LIBCALL 1679 and REG_RETVAL notes too. */ 1680 if (GET_CODE (PATTERN (insn)) == CLOBBER 1681 && (XEXP (PATTERN (insn), 0) == var 1682 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT 1683 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var 1684 || XEXP (XEXP (PATTERN (insn), 0), 1) == var)))) 1685 { 1686 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0) 1687 /* The REG_LIBCALL note will go away since we are going to 1688 turn INSN into a NOTE, so just delete the 1689 corresponding REG_RETVAL note. */ 1690 remove_note (XEXP (note, 0), 1691 find_reg_note (XEXP (note, 0), REG_RETVAL, 1692 NULL_RTX)); 1693 1694 delete_insn (insn); 1695 } 1696 1697 /* The insn to load VAR from a home in the arglist 1698 is now a no-op. When we see it, just delete it. 1699 Similarly if this is storing VAR from a register from which 1700 it was loaded in the previous insn. This will occur 1701 when an ADDRESSOF was made for an arglist slot. */ 1702 else if (toplevel 1703 && (set = single_set (insn)) != 0 1704 && SET_DEST (set) == var 1705 /* If this represents the result of an insn group, 1706 don't delete the insn. */ 1707 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0 1708 && (rtx_equal_p (SET_SRC (set), var) 1709 || (GET_CODE (SET_SRC (set)) == REG 1710 && (prev = prev_nonnote_insn (insn)) != 0 1711 && (prev_set = single_set (prev)) != 0 1712 && SET_DEST (prev_set) == SET_SRC (set) 1713 && rtx_equal_p (SET_SRC (prev_set), var)))) 1714 { 1715 delete_insn (insn); 1716 } 1717 else 1718 { 1719 struct fixup_replacement *replacements = 0; 1720 rtx next_insn = NEXT_INSN (insn); 1721 1722 if (SMALL_REGISTER_CLASSES) 1723 { 1724 /* If the insn that copies the results of a CALL_INSN 1725 into a pseudo now references VAR, we have to use an 1726 intermediate pseudo since we want the life of the 1727 return value register to be only a single insn. 1728 1729 If we don't use an intermediate pseudo, such things as 1730 address computations to make the address of VAR valid 1731 if it is not can be placed between the CALL_INSN and INSN. 1732 1733 To make sure this doesn't happen, we record the destination 1734 of the CALL_INSN and see if the next insn uses both that 1735 and VAR. */ 1736 1737 if (call_dest != 0 && GET_CODE (insn) == INSN 1738 && reg_mentioned_p (var, PATTERN (insn)) 1739 && reg_mentioned_p (call_dest, PATTERN (insn))) 1740 { 1741 rtx temp = gen_reg_rtx (GET_MODE (call_dest)); 1742 1743 emit_insn_before (gen_move_insn (temp, call_dest), insn); 1744 1745 PATTERN (insn) = replace_rtx (PATTERN (insn), 1746 call_dest, temp); 1747 } 1748 1749 if (GET_CODE (insn) == CALL_INSN 1750 && GET_CODE (PATTERN (insn)) == SET) 1751 call_dest = SET_DEST (PATTERN (insn)); 1752 else if (GET_CODE (insn) == CALL_INSN 1753 && GET_CODE (PATTERN (insn)) == PARALLEL 1754 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET) 1755 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0)); 1756 else 1757 call_dest = 0; 1758 } 1759 1760 /* See if we have to do anything to INSN now that VAR is in 1761 memory. If it needs to be loaded into a pseudo, use a single 1762 pseudo for the entire insn in case there is a MATCH_DUP 1763 between two operands. We pass a pointer to the head of 1764 a list of struct fixup_replacements. If fixup_var_refs_1 1765 needs to allocate pseudos or replacement MEMs (for SUBREGs), 1766 it will record them in this list. 1767 1768 If it allocated a pseudo for any replacement, we copy into 1769 it here. */ 1770 1771 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn, 1772 &replacements, no_share); 1773 1774 /* If this is last_parm_insn, and any instructions were output 1775 after it to fix it up, then we must set last_parm_insn to 1776 the last such instruction emitted. */ 1777 if (insn == last_parm_insn) 1778 last_parm_insn = PREV_INSN (next_insn); 1779 1780 while (replacements) 1781 { 1782 struct fixup_replacement *next; 1783 1784 if (GET_CODE (replacements->new) == REG) 1785 { 1786 rtx insert_before; 1787 rtx seq; 1788 1789 /* OLD might be a (subreg (mem)). */ 1790 if (GET_CODE (replacements->old) == SUBREG) 1791 replacements->old 1792 = fixup_memory_subreg (replacements->old, insn, 1793 promoted_mode, 0); 1794 else 1795 replacements->old 1796 = fixup_stack_1 (replacements->old, insn); 1797 1798 insert_before = insn; 1799 1800 /* If we are changing the mode, do a conversion. 1801 This might be wasteful, but combine.c will 1802 eliminate much of the waste. */ 1803 1804 if (GET_MODE (replacements->new) 1805 != GET_MODE (replacements->old)) 1806 { 1807 start_sequence (); 1808 convert_move (replacements->new, 1809 replacements->old, unsignedp); 1810 seq = get_insns (); 1811 end_sequence (); 1812 } 1813 else 1814 seq = gen_move_insn (replacements->new, 1815 replacements->old); 1816 1817 emit_insn_before (seq, insert_before); 1818 } 1819 1820 next = replacements->next; 1821 free (replacements); 1822 replacements = next; 1823 } 1824 } 1825 1826 /* Also fix up any invalid exprs in the REG_NOTES of this insn. 1827 But don't touch other insns referred to by reg-notes; 1828 we will get them elsewhere. */ 1829 while (note) 1830 { 1831 if (GET_CODE (note) != INSN_LIST) 1832 XEXP (note, 0) 1833 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1834 promoted_mode, 1); 1835 note = XEXP (note, 1); 1836 } 1837 } 1838 1839 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE. 1840 See if the rtx expression at *LOC in INSN needs to be changed. 1841 1842 REPLACEMENTS is a pointer to a list head that starts out zero, but may 1843 contain a list of original rtx's and replacements. If we find that we need 1844 to modify this insn by replacing a memory reference with a pseudo or by 1845 making a new MEM to implement a SUBREG, we consult that list to see if 1846 we have already chosen a replacement. If none has already been allocated, 1847 we allocate it and update the list. fixup_var_refs_insn will copy VAR 1848 or the SUBREG, as appropriate, to the pseudo. */ 1849 1850 static void 1851 fixup_var_refs_1 (rtx var, enum machine_mode promoted_mode, rtx *loc, rtx insn, 1852 struct fixup_replacement **replacements, rtx no_share) 1853 { 1854 int i; 1855 rtx x = *loc; 1856 RTX_CODE code = GET_CODE (x); 1857 const char *fmt; 1858 rtx tem, tem1; 1859 struct fixup_replacement *replacement; 1860 1861 switch (code) 1862 { 1863 case ADDRESSOF: 1864 if (XEXP (x, 0) == var) 1865 { 1866 /* Prevent sharing of rtl that might lose. */ 1867 rtx sub = copy_rtx (XEXP (var, 0)); 1868 1869 if (! validate_change (insn, loc, sub, 0)) 1870 { 1871 rtx y = gen_reg_rtx (GET_MODE (sub)); 1872 rtx seq, new_insn; 1873 1874 /* We should be able to replace with a register or all is lost. 1875 Note that we can't use validate_change to verify this, since 1876 we're not caring for replacing all dups simultaneously. */ 1877 if (! validate_replace_rtx (*loc, y, insn)) 1878 abort (); 1879 1880 /* Careful! First try to recognize a direct move of the 1881 value, mimicking how things are done in gen_reload wrt 1882 PLUS. Consider what happens when insn is a conditional 1883 move instruction and addsi3 clobbers flags. */ 1884 1885 start_sequence (); 1886 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub)); 1887 seq = get_insns (); 1888 end_sequence (); 1889 1890 if (recog_memoized (new_insn) < 0) 1891 { 1892 /* That failed. Fall back on force_operand and hope. */ 1893 1894 start_sequence (); 1895 sub = force_operand (sub, y); 1896 if (sub != y) 1897 emit_insn (gen_move_insn (y, sub)); 1898 seq = get_insns (); 1899 end_sequence (); 1900 } 1901 1902 #ifdef HAVE_cc0 1903 /* Don't separate setter from user. */ 1904 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn))) 1905 insn = PREV_INSN (insn); 1906 #endif 1907 1908 emit_insn_before (seq, insn); 1909 } 1910 } 1911 return; 1912 1913 case MEM: 1914 if (var == x) 1915 { 1916 /* If we already have a replacement, use it. Otherwise, 1917 try to fix up this address in case it is invalid. */ 1918 1919 replacement = find_fixup_replacement (replacements, var); 1920 if (replacement->new) 1921 { 1922 *loc = replacement->new; 1923 return; 1924 } 1925 1926 *loc = replacement->new = x = fixup_stack_1 (x, insn); 1927 1928 /* Unless we are forcing memory to register or we changed the mode, 1929 we can leave things the way they are if the insn is valid. */ 1930 1931 INSN_CODE (insn) = -1; 1932 if (! flag_force_mem && GET_MODE (x) == promoted_mode 1933 && recog_memoized (insn) >= 0) 1934 return; 1935 1936 *loc = replacement->new = gen_reg_rtx (promoted_mode); 1937 return; 1938 } 1939 1940 /* If X contains VAR, we need to unshare it here so that we update 1941 each occurrence separately. But all identical MEMs in one insn 1942 must be replaced with the same rtx because of the possibility of 1943 MATCH_DUPs. */ 1944 1945 if (reg_mentioned_p (var, x)) 1946 { 1947 replacement = find_fixup_replacement (replacements, x); 1948 if (replacement->new == 0) 1949 replacement->new = copy_most_rtx (x, no_share); 1950 1951 *loc = x = replacement->new; 1952 code = GET_CODE (x); 1953 } 1954 break; 1955 1956 case REG: 1957 case CC0: 1958 case PC: 1959 case CONST_INT: 1960 case CONST: 1961 case SYMBOL_REF: 1962 case LABEL_REF: 1963 case CONST_DOUBLE: 1964 case CONST_VECTOR: 1965 return; 1966 1967 case SIGN_EXTRACT: 1968 case ZERO_EXTRACT: 1969 /* Note that in some cases those types of expressions are altered 1970 by optimize_bit_field, and do not survive to get here. */ 1971 if (XEXP (x, 0) == var 1972 || (GET_CODE (XEXP (x, 0)) == SUBREG 1973 && SUBREG_REG (XEXP (x, 0)) == var)) 1974 { 1975 /* Get TEM as a valid MEM in the mode presently in the insn. 1976 1977 We don't worry about the possibility of MATCH_DUP here; it 1978 is highly unlikely and would be tricky to handle. */ 1979 1980 tem = XEXP (x, 0); 1981 if (GET_CODE (tem) == SUBREG) 1982 { 1983 if (GET_MODE_BITSIZE (GET_MODE (tem)) 1984 > GET_MODE_BITSIZE (GET_MODE (var))) 1985 { 1986 replacement = find_fixup_replacement (replacements, var); 1987 if (replacement->new == 0) 1988 replacement->new = gen_reg_rtx (GET_MODE (var)); 1989 SUBREG_REG (tem) = replacement->new; 1990 1991 /* The following code works only if we have a MEM, so we 1992 need to handle the subreg here. We directly substitute 1993 it assuming that a subreg must be OK here. We already 1994 scheduled a replacement to copy the mem into the 1995 subreg. */ 1996 XEXP (x, 0) = tem; 1997 return; 1998 } 1999 else 2000 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0); 2001 } 2002 else 2003 tem = fixup_stack_1 (tem, insn); 2004 2005 /* Unless we want to load from memory, get TEM into the proper mode 2006 for an extract from memory. This can only be done if the 2007 extract is at a constant position and length. */ 2008 2009 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT 2010 && GET_CODE (XEXP (x, 2)) == CONST_INT 2011 && ! mode_dependent_address_p (XEXP (tem, 0)) 2012 && ! MEM_VOLATILE_P (tem)) 2013 { 2014 enum machine_mode wanted_mode = VOIDmode; 2015 enum machine_mode is_mode = GET_MODE (tem); 2016 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2)); 2017 2018 if (GET_CODE (x) == ZERO_EXTRACT) 2019 { 2020 enum machine_mode new_mode 2021 = mode_for_extraction (EP_extzv, 1); 2022 if (new_mode != MAX_MACHINE_MODE) 2023 wanted_mode = new_mode; 2024 } 2025 else if (GET_CODE (x) == SIGN_EXTRACT) 2026 { 2027 enum machine_mode new_mode 2028 = mode_for_extraction (EP_extv, 1); 2029 if (new_mode != MAX_MACHINE_MODE) 2030 wanted_mode = new_mode; 2031 } 2032 2033 /* If we have a narrower mode, we can do something. */ 2034 if (wanted_mode != VOIDmode 2035 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode)) 2036 { 2037 HOST_WIDE_INT offset = pos / BITS_PER_UNIT; 2038 rtx old_pos = XEXP (x, 2); 2039 rtx newmem; 2040 2041 /* If the bytes and bits are counted differently, we 2042 must adjust the offset. */ 2043 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN) 2044 offset = (GET_MODE_SIZE (is_mode) 2045 - GET_MODE_SIZE (wanted_mode) - offset); 2046 2047 pos %= GET_MODE_BITSIZE (wanted_mode); 2048 2049 newmem = adjust_address_nv (tem, wanted_mode, offset); 2050 2051 /* Make the change and see if the insn remains valid. */ 2052 INSN_CODE (insn) = -1; 2053 XEXP (x, 0) = newmem; 2054 XEXP (x, 2) = GEN_INT (pos); 2055 2056 if (recog_memoized (insn) >= 0) 2057 return; 2058 2059 /* Otherwise, restore old position. XEXP (x, 0) will be 2060 restored later. */ 2061 XEXP (x, 2) = old_pos; 2062 } 2063 } 2064 2065 /* If we get here, the bitfield extract insn can't accept a memory 2066 reference. Copy the input into a register. */ 2067 2068 tem1 = gen_reg_rtx (GET_MODE (tem)); 2069 emit_insn_before (gen_move_insn (tem1, tem), insn); 2070 XEXP (x, 0) = tem1; 2071 return; 2072 } 2073 break; 2074 2075 case SUBREG: 2076 if (SUBREG_REG (x) == var) 2077 { 2078 /* If this is a special SUBREG made because VAR was promoted 2079 from a wider mode, replace it with VAR and call ourself 2080 recursively, this time saying that the object previously 2081 had its current mode (by virtue of the SUBREG). */ 2082 2083 if (SUBREG_PROMOTED_VAR_P (x)) 2084 { 2085 *loc = var; 2086 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements, 2087 no_share); 2088 return; 2089 } 2090 2091 /* If this SUBREG makes VAR wider, it has become a paradoxical 2092 SUBREG with VAR in memory, but these aren't allowed at this 2093 stage of the compilation. So load VAR into a pseudo and take 2094 a SUBREG of that pseudo. */ 2095 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var))) 2096 { 2097 replacement = find_fixup_replacement (replacements, var); 2098 if (replacement->new == 0) 2099 replacement->new = gen_reg_rtx (promoted_mode); 2100 SUBREG_REG (x) = replacement->new; 2101 return; 2102 } 2103 2104 /* See if we have already found a replacement for this SUBREG. 2105 If so, use it. Otherwise, make a MEM and see if the insn 2106 is recognized. If not, or if we should force MEM into a register, 2107 make a pseudo for this SUBREG. */ 2108 replacement = find_fixup_replacement (replacements, x); 2109 if (replacement->new) 2110 { 2111 enum machine_mode mode = GET_MODE (x); 2112 *loc = replacement->new; 2113 2114 /* Careful! We may have just replaced a SUBREG by a MEM, which 2115 means that the insn may have become invalid again. We can't 2116 in this case make a new replacement since we already have one 2117 and we must deal with MATCH_DUPs. */ 2118 if (GET_CODE (replacement->new) == MEM) 2119 { 2120 INSN_CODE (insn) = -1; 2121 if (recog_memoized (insn) >= 0) 2122 return; 2123 2124 fixup_var_refs_1 (replacement->new, mode, &PATTERN (insn), 2125 insn, replacements, no_share); 2126 } 2127 2128 return; 2129 } 2130 2131 replacement->new = *loc = fixup_memory_subreg (x, insn, 2132 promoted_mode, 0); 2133 2134 INSN_CODE (insn) = -1; 2135 if (! flag_force_mem && recog_memoized (insn) >= 0) 2136 return; 2137 2138 *loc = replacement->new = gen_reg_rtx (GET_MODE (x)); 2139 return; 2140 } 2141 break; 2142 2143 case SET: 2144 /* First do special simplification of bit-field references. */ 2145 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT 2146 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT) 2147 optimize_bit_field (x, insn, 0); 2148 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT 2149 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT) 2150 optimize_bit_field (x, insn, 0); 2151 2152 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object 2153 into a register and then store it back out. */ 2154 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT 2155 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG 2156 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var 2157 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0))) 2158 > GET_MODE_SIZE (GET_MODE (var)))) 2159 { 2160 replacement = find_fixup_replacement (replacements, var); 2161 if (replacement->new == 0) 2162 replacement->new = gen_reg_rtx (GET_MODE (var)); 2163 2164 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new; 2165 emit_insn_after (gen_move_insn (var, replacement->new), insn); 2166 } 2167 2168 /* If SET_DEST is now a paradoxical SUBREG, put the result of this 2169 insn into a pseudo and store the low part of the pseudo into VAR. */ 2170 if (GET_CODE (SET_DEST (x)) == SUBREG 2171 && SUBREG_REG (SET_DEST (x)) == var 2172 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x))) 2173 > GET_MODE_SIZE (GET_MODE (var)))) 2174 { 2175 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x))); 2176 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var), 2177 tem)), 2178 insn); 2179 break; 2180 } 2181 2182 { 2183 rtx dest = SET_DEST (x); 2184 rtx src = SET_SRC (x); 2185 rtx outerdest = dest; 2186 2187 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART 2188 || GET_CODE (dest) == SIGN_EXTRACT 2189 || GET_CODE (dest) == ZERO_EXTRACT) 2190 dest = XEXP (dest, 0); 2191 2192 if (GET_CODE (src) == SUBREG) 2193 src = SUBREG_REG (src); 2194 2195 /* If VAR does not appear at the top level of the SET 2196 just scan the lower levels of the tree. */ 2197 2198 if (src != var && dest != var) 2199 break; 2200 2201 /* We will need to rerecognize this insn. */ 2202 INSN_CODE (insn) = -1; 2203 2204 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var 2205 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE) 2206 { 2207 /* Since this case will return, ensure we fixup all the 2208 operands here. */ 2209 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1), 2210 insn, replacements, no_share); 2211 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2), 2212 insn, replacements, no_share); 2213 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x), 2214 insn, replacements, no_share); 2215 2216 tem = XEXP (outerdest, 0); 2217 2218 /* Clean up (SUBREG:SI (MEM:mode ...) 0) 2219 that may appear inside a ZERO_EXTRACT. 2220 This was legitimate when the MEM was a REG. */ 2221 if (GET_CODE (tem) == SUBREG 2222 && SUBREG_REG (tem) == var) 2223 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0); 2224 else 2225 tem = fixup_stack_1 (tem, insn); 2226 2227 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT 2228 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT 2229 && ! mode_dependent_address_p (XEXP (tem, 0)) 2230 && ! MEM_VOLATILE_P (tem)) 2231 { 2232 enum machine_mode wanted_mode; 2233 enum machine_mode is_mode = GET_MODE (tem); 2234 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2)); 2235 2236 wanted_mode = mode_for_extraction (EP_insv, 0); 2237 2238 /* If we have a narrower mode, we can do something. */ 2239 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode)) 2240 { 2241 HOST_WIDE_INT offset = pos / BITS_PER_UNIT; 2242 rtx old_pos = XEXP (outerdest, 2); 2243 rtx newmem; 2244 2245 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN) 2246 offset = (GET_MODE_SIZE (is_mode) 2247 - GET_MODE_SIZE (wanted_mode) - offset); 2248 2249 pos %= GET_MODE_BITSIZE (wanted_mode); 2250 2251 newmem = adjust_address_nv (tem, wanted_mode, offset); 2252 2253 /* Make the change and see if the insn remains valid. */ 2254 INSN_CODE (insn) = -1; 2255 XEXP (outerdest, 0) = newmem; 2256 XEXP (outerdest, 2) = GEN_INT (pos); 2257 2258 if (recog_memoized (insn) >= 0) 2259 return; 2260 2261 /* Otherwise, restore old position. XEXP (x, 0) will be 2262 restored later. */ 2263 XEXP (outerdest, 2) = old_pos; 2264 } 2265 } 2266 2267 /* If we get here, the bit-field store doesn't allow memory 2268 or isn't located at a constant position. Load the value into 2269 a register, do the store, and put it back into memory. */ 2270 2271 tem1 = gen_reg_rtx (GET_MODE (tem)); 2272 emit_insn_before (gen_move_insn (tem1, tem), insn); 2273 emit_insn_after (gen_move_insn (tem, tem1), insn); 2274 XEXP (outerdest, 0) = tem1; 2275 return; 2276 } 2277 2278 /* STRICT_LOW_PART is a no-op on memory references 2279 and it can cause combinations to be unrecognizable, 2280 so eliminate it. */ 2281 2282 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART) 2283 SET_DEST (x) = XEXP (SET_DEST (x), 0); 2284 2285 /* A valid insn to copy VAR into or out of a register 2286 must be left alone, to avoid an infinite loop here. 2287 If the reference to VAR is by a subreg, fix that up, 2288 since SUBREG is not valid for a memref. 2289 Also fix up the address of the stack slot. 2290 2291 Note that we must not try to recognize the insn until 2292 after we know that we have valid addresses and no 2293 (subreg (mem ...) ...) constructs, since these interfere 2294 with determining the validity of the insn. */ 2295 2296 if ((SET_SRC (x) == var 2297 || (GET_CODE (SET_SRC (x)) == SUBREG 2298 && SUBREG_REG (SET_SRC (x)) == var)) 2299 && (GET_CODE (SET_DEST (x)) == REG 2300 || (GET_CODE (SET_DEST (x)) == SUBREG 2301 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG)) 2302 && GET_MODE (var) == promoted_mode 2303 && x == single_set (insn)) 2304 { 2305 rtx pat, last; 2306 2307 if (GET_CODE (SET_SRC (x)) == SUBREG 2308 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x))) 2309 > GET_MODE_SIZE (GET_MODE (var)))) 2310 { 2311 /* This (subreg VAR) is now a paradoxical subreg. We need 2312 to replace VAR instead of the subreg. */ 2313 replacement = find_fixup_replacement (replacements, var); 2314 if (replacement->new == NULL_RTX) 2315 replacement->new = gen_reg_rtx (GET_MODE (var)); 2316 SUBREG_REG (SET_SRC (x)) = replacement->new; 2317 } 2318 else 2319 { 2320 replacement = find_fixup_replacement (replacements, SET_SRC (x)); 2321 if (replacement->new) 2322 SET_SRC (x) = replacement->new; 2323 else if (GET_CODE (SET_SRC (x)) == SUBREG) 2324 SET_SRC (x) = replacement->new 2325 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode, 2326 0); 2327 else 2328 SET_SRC (x) = replacement->new 2329 = fixup_stack_1 (SET_SRC (x), insn); 2330 } 2331 2332 if (recog_memoized (insn) >= 0) 2333 return; 2334 2335 /* INSN is not valid, but we know that we want to 2336 copy SET_SRC (x) to SET_DEST (x) in some way. So 2337 we generate the move and see whether it requires more 2338 than one insn. If it does, we emit those insns and 2339 delete INSN. Otherwise, we can just replace the pattern 2340 of INSN; we have already verified above that INSN has 2341 no other function that to do X. */ 2342 2343 pat = gen_move_insn (SET_DEST (x), SET_SRC (x)); 2344 if (NEXT_INSN (pat) != NULL_RTX) 2345 { 2346 last = emit_insn_before (pat, insn); 2347 2348 /* INSN might have REG_RETVAL or other important notes, so 2349 we need to store the pattern of the last insn in the 2350 sequence into INSN similarly to the normal case. LAST 2351 should not have REG_NOTES, but we allow them if INSN has 2352 no REG_NOTES. */ 2353 if (REG_NOTES (last) && REG_NOTES (insn)) 2354 abort (); 2355 if (REG_NOTES (last)) 2356 REG_NOTES (insn) = REG_NOTES (last); 2357 PATTERN (insn) = PATTERN (last); 2358 2359 delete_insn (last); 2360 } 2361 else 2362 PATTERN (insn) = PATTERN (pat); 2363 2364 return; 2365 } 2366 2367 if ((SET_DEST (x) == var 2368 || (GET_CODE (SET_DEST (x)) == SUBREG 2369 && SUBREG_REG (SET_DEST (x)) == var)) 2370 && (GET_CODE (SET_SRC (x)) == REG 2371 || (GET_CODE (SET_SRC (x)) == SUBREG 2372 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG)) 2373 && GET_MODE (var) == promoted_mode 2374 && x == single_set (insn)) 2375 { 2376 rtx pat, last; 2377 2378 if (GET_CODE (SET_DEST (x)) == SUBREG) 2379 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 2380 promoted_mode, 0); 2381 else 2382 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn); 2383 2384 if (recog_memoized (insn) >= 0) 2385 return; 2386 2387 pat = gen_move_insn (SET_DEST (x), SET_SRC (x)); 2388 if (NEXT_INSN (pat) != NULL_RTX) 2389 { 2390 last = emit_insn_before (pat, insn); 2391 2392 /* INSN might have REG_RETVAL or other important notes, so 2393 we need to store the pattern of the last insn in the 2394 sequence into INSN similarly to the normal case. LAST 2395 should not have REG_NOTES, but we allow them if INSN has 2396 no REG_NOTES. */ 2397 if (REG_NOTES (last) && REG_NOTES (insn)) 2398 abort (); 2399 if (REG_NOTES (last)) 2400 REG_NOTES (insn) = REG_NOTES (last); 2401 PATTERN (insn) = PATTERN (last); 2402 2403 delete_insn (last); 2404 } 2405 else 2406 PATTERN (insn) = PATTERN (pat); 2407 2408 return; 2409 } 2410 2411 /* Otherwise, storing into VAR must be handled specially 2412 by storing into a temporary and copying that into VAR 2413 with a new insn after this one. Note that this case 2414 will be used when storing into a promoted scalar since 2415 the insn will now have different modes on the input 2416 and output and hence will be invalid (except for the case 2417 of setting it to a constant, which does not need any 2418 change if it is valid). We generate extra code in that case, 2419 but combine.c will eliminate it. */ 2420 2421 if (dest == var) 2422 { 2423 rtx temp; 2424 rtx fixeddest = SET_DEST (x); 2425 enum machine_mode temp_mode; 2426 2427 /* STRICT_LOW_PART can be discarded, around a MEM. */ 2428 if (GET_CODE (fixeddest) == STRICT_LOW_PART) 2429 fixeddest = XEXP (fixeddest, 0); 2430 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */ 2431 if (GET_CODE (fixeddest) == SUBREG) 2432 { 2433 fixeddest = fixup_memory_subreg (fixeddest, insn, 2434 promoted_mode, 0); 2435 temp_mode = GET_MODE (fixeddest); 2436 } 2437 else 2438 { 2439 fixeddest = fixup_stack_1 (fixeddest, insn); 2440 temp_mode = promoted_mode; 2441 } 2442 2443 temp = gen_reg_rtx (temp_mode); 2444 2445 emit_insn_after (gen_move_insn (fixeddest, 2446 gen_lowpart (GET_MODE (fixeddest), 2447 temp)), 2448 insn); 2449 2450 SET_DEST (x) = temp; 2451 } 2452 } 2453 2454 default: 2455 break; 2456 } 2457 2458 /* Nothing special about this RTX; fix its operands. */ 2459 2460 fmt = GET_RTX_FORMAT (code); 2461 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 2462 { 2463 if (fmt[i] == 'e') 2464 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements, 2465 no_share); 2466 else if (fmt[i] == 'E') 2467 { 2468 int j; 2469 for (j = 0; j < XVECLEN (x, i); j++) 2470 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j), 2471 insn, replacements, no_share); 2472 } 2473 } 2474 } 2475 2476 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)). 2477 The REG was placed on the stack, so X now has the form (SUBREG:m1 2478 (MEM:m2 ...)). 2479 2480 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns 2481 must be emitted to compute NEWADDR, put them before INSN. 2482 2483 UNCRITICAL nonzero means accept paradoxical subregs. 2484 This is used for subregs found inside REG_NOTES. */ 2485 2486 static rtx 2487 fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode, int uncritical) 2488 { 2489 int offset; 2490 rtx mem = SUBREG_REG (x); 2491 rtx addr = XEXP (mem, 0); 2492 enum machine_mode mode = GET_MODE (x); 2493 rtx result, seq; 2494 2495 /* Paradoxical SUBREGs are usually invalid during RTL generation. */ 2496 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical) 2497 abort (); 2498 2499 offset = SUBREG_BYTE (x); 2500 if (BYTES_BIG_ENDIAN) 2501 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust 2502 the offset so that it points to the right location within the 2503 MEM. */ 2504 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem))); 2505 2506 if (!flag_force_addr 2507 && memory_address_p (mode, plus_constant (addr, offset))) 2508 /* Shortcut if no insns need be emitted. */ 2509 return adjust_address (mem, mode, offset); 2510 2511 start_sequence (); 2512 result = adjust_address (mem, mode, offset); 2513 seq = get_insns (); 2514 end_sequence (); 2515 2516 emit_insn_before (seq, insn); 2517 return result; 2518 } 2519 2520 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X. 2521 Replace subexpressions of X in place. 2522 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression. 2523 Otherwise return X, with its contents possibly altered. 2524 2525 INSN, PROMOTED_MODE and UNCRITICAL are as for 2526 fixup_memory_subreg. */ 2527 2528 static rtx 2529 walk_fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode, 2530 int uncritical) 2531 { 2532 enum rtx_code code; 2533 const char *fmt; 2534 int i; 2535 2536 if (x == 0) 2537 return 0; 2538 2539 code = GET_CODE (x); 2540 2541 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM) 2542 return fixup_memory_subreg (x, insn, promoted_mode, uncritical); 2543 2544 /* Nothing special about this RTX; fix its operands. */ 2545 2546 fmt = GET_RTX_FORMAT (code); 2547 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 2548 { 2549 if (fmt[i] == 'e') 2550 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, 2551 promoted_mode, uncritical); 2552 else if (fmt[i] == 'E') 2553 { 2554 int j; 2555 for (j = 0; j < XVECLEN (x, i); j++) 2556 XVECEXP (x, i, j) 2557 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, 2558 promoted_mode, uncritical); 2559 } 2560 } 2561 return x; 2562 } 2563 2564 /* For each memory ref within X, if it refers to a stack slot 2565 with an out of range displacement, put the address in a temp register 2566 (emitting new insns before INSN to load these registers) 2567 and alter the memory ref to use that register. 2568 Replace each such MEM rtx with a copy, to avoid clobberage. */ 2569 2570 static rtx 2571 fixup_stack_1 (rtx x, rtx insn) 2572 { 2573 int i; 2574 RTX_CODE code = GET_CODE (x); 2575 const char *fmt; 2576 2577 if (code == MEM) 2578 { 2579 rtx ad = XEXP (x, 0); 2580 /* If we have address of a stack slot but it's not valid 2581 (displacement is too large), compute the sum in a register. */ 2582 if (GET_CODE (ad) == PLUS 2583 && GET_CODE (XEXP (ad, 0)) == REG 2584 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER 2585 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER) 2586 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM 2587 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM 2588 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM 2589 #endif 2590 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM 2591 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM 2592 || XEXP (ad, 0) == current_function_internal_arg_pointer) 2593 && GET_CODE (XEXP (ad, 1)) == CONST_INT) 2594 { 2595 rtx temp, seq; 2596 if (memory_address_p (GET_MODE (x), ad)) 2597 return x; 2598 2599 start_sequence (); 2600 temp = copy_to_reg (ad); 2601 seq = get_insns (); 2602 end_sequence (); 2603 emit_insn_before (seq, insn); 2604 return replace_equiv_address (x, temp); 2605 } 2606 return x; 2607 } 2608 2609 fmt = GET_RTX_FORMAT (code); 2610 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 2611 { 2612 if (fmt[i] == 'e') 2613 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn); 2614 else if (fmt[i] == 'E') 2615 { 2616 int j; 2617 for (j = 0; j < XVECLEN (x, i); j++) 2618 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn); 2619 } 2620 } 2621 return x; 2622 } 2623 2624 /* Optimization: a bit-field instruction whose field 2625 happens to be a byte or halfword in memory 2626 can be changed to a move instruction. 2627 2628 We call here when INSN is an insn to examine or store into a bit-field. 2629 BODY is the SET-rtx to be altered. 2630 2631 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0. 2632 (Currently this is called only from function.c, and EQUIV_MEM 2633 is always 0.) */ 2634 2635 static void 2636 optimize_bit_field (rtx body, rtx insn, rtx *equiv_mem) 2637 { 2638 rtx bitfield; 2639 int destflag; 2640 rtx seq = 0; 2641 enum machine_mode mode; 2642 2643 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT 2644 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT) 2645 bitfield = SET_DEST (body), destflag = 1; 2646 else 2647 bitfield = SET_SRC (body), destflag = 0; 2648 2649 /* First check that the field being stored has constant size and position 2650 and is in fact a byte or halfword suitably aligned. */ 2651 2652 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT 2653 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT 2654 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1)) 2655 != BLKmode) 2656 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0) 2657 { 2658 rtx memref = 0; 2659 2660 /* Now check that the containing word is memory, not a register, 2661 and that it is safe to change the machine mode. */ 2662 2663 if (GET_CODE (XEXP (bitfield, 0)) == MEM) 2664 memref = XEXP (bitfield, 0); 2665 else if (GET_CODE (XEXP (bitfield, 0)) == REG 2666 && equiv_mem != 0) 2667 memref = equiv_mem[REGNO (XEXP (bitfield, 0))]; 2668 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG 2669 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM) 2670 memref = SUBREG_REG (XEXP (bitfield, 0)); 2671 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG 2672 && equiv_mem != 0 2673 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG) 2674 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))]; 2675 2676 if (memref 2677 && ! mode_dependent_address_p (XEXP (memref, 0)) 2678 && ! MEM_VOLATILE_P (memref)) 2679 { 2680 /* Now adjust the address, first for any subreg'ing 2681 that we are now getting rid of, 2682 and then for which byte of the word is wanted. */ 2683 2684 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2)); 2685 rtx insns; 2686 2687 /* Adjust OFFSET to count bits from low-address byte. */ 2688 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN) 2689 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0))) 2690 - offset - INTVAL (XEXP (bitfield, 1))); 2691 2692 /* Adjust OFFSET to count bytes from low-address byte. */ 2693 offset /= BITS_PER_UNIT; 2694 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG) 2695 { 2696 offset += (SUBREG_BYTE (XEXP (bitfield, 0)) 2697 / UNITS_PER_WORD) * UNITS_PER_WORD; 2698 if (BYTES_BIG_ENDIAN) 2699 offset -= (MIN (UNITS_PER_WORD, 2700 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0)))) 2701 - MIN (UNITS_PER_WORD, 2702 GET_MODE_SIZE (GET_MODE (memref)))); 2703 } 2704 2705 start_sequence (); 2706 memref = adjust_address (memref, mode, offset); 2707 insns = get_insns (); 2708 end_sequence (); 2709 emit_insn_before (insns, insn); 2710 2711 /* Store this memory reference where 2712 we found the bit field reference. */ 2713 2714 if (destflag) 2715 { 2716 validate_change (insn, &SET_DEST (body), memref, 1); 2717 if (! CONSTANT_ADDRESS_P (SET_SRC (body))) 2718 { 2719 rtx src = SET_SRC (body); 2720 while (GET_CODE (src) == SUBREG 2721 && SUBREG_BYTE (src) == 0) 2722 src = SUBREG_REG (src); 2723 if (GET_MODE (src) != GET_MODE (memref)) 2724 src = gen_lowpart (GET_MODE (memref), SET_SRC (body)); 2725 validate_change (insn, &SET_SRC (body), src, 1); 2726 } 2727 else if (GET_MODE (SET_SRC (body)) != VOIDmode 2728 && GET_MODE (SET_SRC (body)) != GET_MODE (memref)) 2729 /* This shouldn't happen because anything that didn't have 2730 one of these modes should have got converted explicitly 2731 and then referenced through a subreg. 2732 This is so because the original bit-field was 2733 handled by agg_mode and so its tree structure had 2734 the same mode that memref now has. */ 2735 abort (); 2736 } 2737 else 2738 { 2739 rtx dest = SET_DEST (body); 2740 2741 while (GET_CODE (dest) == SUBREG 2742 && SUBREG_BYTE (dest) == 0 2743 && (GET_MODE_CLASS (GET_MODE (dest)) 2744 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest)))) 2745 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest))) 2746 <= UNITS_PER_WORD)) 2747 dest = SUBREG_REG (dest); 2748 2749 validate_change (insn, &SET_DEST (body), dest, 1); 2750 2751 if (GET_MODE (dest) == GET_MODE (memref)) 2752 validate_change (insn, &SET_SRC (body), memref, 1); 2753 else 2754 { 2755 /* Convert the mem ref to the destination mode. */ 2756 rtx newreg = gen_reg_rtx (GET_MODE (dest)); 2757 2758 start_sequence (); 2759 convert_move (newreg, memref, 2760 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT); 2761 seq = get_insns (); 2762 end_sequence (); 2763 2764 validate_change (insn, &SET_SRC (body), newreg, 1); 2765 } 2766 } 2767 2768 /* See if we can convert this extraction or insertion into 2769 a simple move insn. We might not be able to do so if this 2770 was, for example, part of a PARALLEL. 2771 2772 If we succeed, write out any needed conversions. If we fail, 2773 it is hard to guess why we failed, so don't do anything 2774 special; just let the optimization be suppressed. */ 2775 2776 if (apply_change_group () && seq) 2777 emit_insn_before (seq, insn); 2778 } 2779 } 2780 } 2781 2782 /* These routines are responsible for converting virtual register references 2783 to the actual hard register references once RTL generation is complete. 2784 2785 The following four variables are used for communication between the 2786 routines. They contain the offsets of the virtual registers from their 2787 respective hard registers. */ 2788 2789 static int in_arg_offset; 2790 static int var_offset; 2791 static int dynamic_offset; 2792 static int out_arg_offset; 2793 static int cfa_offset; 2794 2795 /* In most machines, the stack pointer register is equivalent to the bottom 2796 of the stack. */ 2797 2798 #ifndef STACK_POINTER_OFFSET 2799 #define STACK_POINTER_OFFSET 0 2800 #endif 2801 2802 /* If not defined, pick an appropriate default for the offset of dynamically 2803 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS, 2804 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */ 2805 2806 #ifndef STACK_DYNAMIC_OFFSET 2807 2808 /* The bottom of the stack points to the actual arguments. If 2809 REG_PARM_STACK_SPACE is defined, this includes the space for the register 2810 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined, 2811 stack space for register parameters is not pushed by the caller, but 2812 rather part of the fixed stack areas and hence not included in 2813 `current_function_outgoing_args_size'. Nevertheless, we must allow 2814 for it when allocating stack dynamic objects. */ 2815 2816 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE) 2817 #define STACK_DYNAMIC_OFFSET(FNDECL) \ 2818 ((ACCUMULATE_OUTGOING_ARGS \ 2819 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\ 2820 + (STACK_POINTER_OFFSET)) \ 2821 2822 #else 2823 #define STACK_DYNAMIC_OFFSET(FNDECL) \ 2824 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \ 2825 + (STACK_POINTER_OFFSET)) 2826 #endif 2827 #endif 2828 2829 /* On most machines, the CFA coincides with the first incoming parm. */ 2830 2831 #ifndef ARG_POINTER_CFA_OFFSET 2832 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL) 2833 #endif 2834 2835 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just 2836 had its address taken. DECL is the decl or SAVE_EXPR for the 2837 object stored in the register, for later use if we do need to force 2838 REG into the stack. REG is overwritten by the MEM like in 2839 put_reg_into_stack. RESCAN is true if previously emitted 2840 instructions must be rescanned and modified now that the REG has 2841 been transformed. */ 2842 2843 rtx 2844 gen_mem_addressof (rtx reg, tree decl, int rescan) 2845 { 2846 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)), 2847 REGNO (reg), decl); 2848 2849 /* Calculate this before we start messing with decl's RTL. */ 2850 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0; 2851 2852 /* If the original REG was a user-variable, then so is the REG whose 2853 address is being taken. Likewise for unchanging. */ 2854 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg); 2855 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg); 2856 2857 PUT_CODE (reg, MEM); 2858 MEM_ATTRS (reg) = 0; 2859 XEXP (reg, 0) = r; 2860 2861 if (decl) 2862 { 2863 tree type = TREE_TYPE (decl); 2864 enum machine_mode decl_mode 2865 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl))); 2866 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) 2867 : DECL_RTL_IF_SET (decl)); 2868 2869 PUT_MODE (reg, decl_mode); 2870 2871 /* Clear DECL_RTL momentarily so functions below will work 2872 properly, then set it again. */ 2873 if (DECL_P (decl) && decl_rtl == reg) 2874 SET_DECL_RTL (decl, 0); 2875 2876 set_mem_attributes (reg, decl, 1); 2877 set_mem_alias_set (reg, set); 2878 2879 if (DECL_P (decl) && decl_rtl == reg) 2880 SET_DECL_RTL (decl, reg); 2881 2882 if (rescan 2883 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0))) 2884 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0); 2885 } 2886 else if (rescan) 2887 { 2888 /* This can only happen during reload. Clear the same flag bits as 2889 reload. */ 2890 MEM_VOLATILE_P (reg) = 0; 2891 RTX_UNCHANGING_P (reg) = 0; 2892 MEM_IN_STRUCT_P (reg) = 0; 2893 MEM_SCALAR_P (reg) = 0; 2894 MEM_ATTRS (reg) = 0; 2895 2896 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0); 2897 } 2898 2899 return reg; 2900 } 2901 2902 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */ 2903 2904 void 2905 flush_addressof (tree decl) 2906 { 2907 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL) 2908 && DECL_RTL (decl) != 0 2909 && GET_CODE (DECL_RTL (decl)) == MEM 2910 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF 2911 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG) 2912 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0); 2913 } 2914 2915 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */ 2916 2917 static void 2918 put_addressof_into_stack (rtx r, htab_t ht) 2919 { 2920 tree decl, type; 2921 bool volatile_p, used_p; 2922 2923 rtx reg = XEXP (r, 0); 2924 2925 if (GET_CODE (reg) != REG) 2926 abort (); 2927 2928 decl = ADDRESSOF_DECL (r); 2929 if (decl) 2930 { 2931 type = TREE_TYPE (decl); 2932 volatile_p = (TREE_CODE (decl) != SAVE_EXPR 2933 && TREE_THIS_VOLATILE (decl)); 2934 used_p = (TREE_USED (decl) 2935 || (DECL_P (decl) && DECL_INITIAL (decl) != 0)); 2936 } 2937 else 2938 { 2939 type = NULL_TREE; 2940 volatile_p = false; 2941 used_p = true; 2942 } 2943 2944 put_reg_into_stack (0, reg, type, GET_MODE (reg), ADDRESSOF_REGNO (r), 2945 volatile_p, used_p, false, ht); 2946 } 2947 2948 /* List of replacements made below in purge_addressof_1 when creating 2949 bitfield insertions. */ 2950 static rtx purge_bitfield_addressof_replacements; 2951 2952 /* List of replacements made below in purge_addressof_1 for patterns 2953 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the 2954 corresponding (ADDRESSOF (REG ...)) and value is a substitution for 2955 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not 2956 enough in complex cases, e.g. when some field values can be 2957 extracted by usage MEM with narrower mode. */ 2958 static rtx purge_addressof_replacements; 2959 2960 /* Helper function for purge_addressof. See if the rtx expression at *LOC 2961 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into 2962 the stack. If the function returns FALSE then the replacement could not 2963 be made. If MAY_POSTPONE is true and we would not put the addressof 2964 to stack, postpone processing of the insn. */ 2965 2966 static bool 2967 purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone, 2968 htab_t ht) 2969 { 2970 rtx x; 2971 RTX_CODE code; 2972 int i, j; 2973 const char *fmt; 2974 bool result = true; 2975 bool libcall = false; 2976 2977 /* Re-start here to avoid recursion in common cases. */ 2978 restart: 2979 2980 x = *loc; 2981 if (x == 0) 2982 return true; 2983 2984 /* Is this a libcall? */ 2985 if (!insn) 2986 libcall = REG_NOTE_KIND (*loc) == REG_RETVAL; 2987 2988 code = GET_CODE (x); 2989 2990 /* If we don't return in any of the cases below, we will recurse inside 2991 the RTX, which will normally result in any ADDRESSOF being forced into 2992 memory. */ 2993 if (code == SET) 2994 { 2995 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, 2996 may_postpone, ht); 2997 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, 2998 may_postpone, ht); 2999 return result; 3000 } 3001 else if (code == ADDRESSOF) 3002 { 3003 rtx sub, insns; 3004 3005 if (GET_CODE (XEXP (x, 0)) != MEM) 3006 put_addressof_into_stack (x, ht); 3007 3008 /* We must create a copy of the rtx because it was created by 3009 overwriting a REG rtx which is always shared. */ 3010 sub = copy_rtx (XEXP (XEXP (x, 0), 0)); 3011 if (validate_change (insn, loc, sub, 0) 3012 || validate_replace_rtx (x, sub, insn)) 3013 return true; 3014 3015 start_sequence (); 3016 3017 /* If SUB is a hard or virtual register, try it as a pseudo-register. 3018 Otherwise, perhaps SUB is an expression, so generate code to compute 3019 it. */ 3020 if (GET_CODE (sub) == REG && REGNO (sub) <= LAST_VIRTUAL_REGISTER) 3021 sub = copy_to_reg (sub); 3022 else 3023 sub = force_operand (sub, NULL_RTX); 3024 3025 if (! validate_change (insn, loc, sub, 0) 3026 && ! validate_replace_rtx (x, sub, insn)) 3027 abort (); 3028 3029 insns = get_insns (); 3030 end_sequence (); 3031 emit_insn_before (insns, insn); 3032 return true; 3033 } 3034 3035 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force) 3036 { 3037 rtx sub = XEXP (XEXP (x, 0), 0); 3038 3039 if (GET_CODE (sub) == MEM) 3040 sub = adjust_address_nv (sub, GET_MODE (x), 0); 3041 else if (GET_CODE (sub) == REG 3042 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode)) 3043 ; 3044 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub)) 3045 { 3046 int size_x, size_sub; 3047 3048 if (may_postpone) 3049 { 3050 /* Postpone for now, so that we do not emit bitfield arithmetics 3051 unless there is some benefit from it. */ 3052 if (!postponed_insns || XEXP (postponed_insns, 0) != insn) 3053 postponed_insns = alloc_INSN_LIST (insn, postponed_insns); 3054 return true; 3055 } 3056 3057 if (!insn) 3058 { 3059 /* When processing REG_NOTES look at the list of 3060 replacements done on the insn to find the register that X 3061 was replaced by. */ 3062 rtx tem; 3063 3064 for (tem = purge_bitfield_addressof_replacements; 3065 tem != NULL_RTX; 3066 tem = XEXP (XEXP (tem, 1), 1)) 3067 if (rtx_equal_p (x, XEXP (tem, 0))) 3068 { 3069 *loc = XEXP (XEXP (tem, 1), 0); 3070 return true; 3071 } 3072 3073 /* See comment for purge_addressof_replacements. */ 3074 for (tem = purge_addressof_replacements; 3075 tem != NULL_RTX; 3076 tem = XEXP (XEXP (tem, 1), 1)) 3077 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0))) 3078 { 3079 rtx z = XEXP (XEXP (tem, 1), 0); 3080 3081 if (GET_MODE (x) == GET_MODE (z) 3082 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG 3083 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG)) 3084 abort (); 3085 3086 /* It can happen that the note may speak of things 3087 in a wider (or just different) mode than the 3088 code did. This is especially true of 3089 REG_RETVAL. */ 3090 3091 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0) 3092 z = SUBREG_REG (z); 3093 3094 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD 3095 && (GET_MODE_SIZE (GET_MODE (x)) 3096 > GET_MODE_SIZE (GET_MODE (z)))) 3097 { 3098 /* This can occur as a result in invalid 3099 pointer casts, e.g. float f; ... 3100 *(long long int *)&f. 3101 ??? We could emit a warning here, but 3102 without a line number that wouldn't be 3103 very helpful. */ 3104 z = gen_rtx_SUBREG (GET_MODE (x), z, 0); 3105 } 3106 else 3107 z = gen_lowpart (GET_MODE (x), z); 3108 3109 *loc = z; 3110 return true; 3111 } 3112 3113 /* When we are processing the REG_NOTES of the last instruction 3114 of a libcall, there will be typically no replacements 3115 for that insn; the replacements happened before, piecemeal 3116 fashion. OTOH we are not interested in the details of 3117 this for the REG_EQUAL note, we want to know the big picture, 3118 which can be succinctly described with a simple SUBREG. 3119 Note that removing the REG_EQUAL note is not an option 3120 on the last insn of a libcall, so we must do a replacement. */ 3121 3122 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf, 3123 we got 3124 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510) 3125 [0 S8 A32]), which can be expressed with a simple 3126 same-size subreg */ 3127 if ((GET_MODE_SIZE (GET_MODE (x)) 3128 <= GET_MODE_SIZE (GET_MODE (sub))) 3129 /* Again, invalid pointer casts (as in 3130 compile/990203-1.c) can require paradoxical 3131 subregs. */ 3132 || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD 3133 && (GET_MODE_SIZE (GET_MODE (x)) 3134 > GET_MODE_SIZE (GET_MODE (sub))) 3135 && libcall)) 3136 { 3137 *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0); 3138 return true; 3139 } 3140 /* ??? Are there other cases we should handle? */ 3141 3142 /* Sometimes we may not be able to find the replacement. For 3143 example when the original insn was a MEM in a wider mode, 3144 and the note is part of a sign extension of a narrowed 3145 version of that MEM. Gcc testcase compile/990829-1.c can 3146 generate an example of this situation. Rather than complain 3147 we return false, which will prompt our caller to remove the 3148 offending note. */ 3149 return false; 3150 } 3151 3152 size_x = GET_MODE_BITSIZE (GET_MODE (x)); 3153 size_sub = GET_MODE_BITSIZE (GET_MODE (sub)); 3154 3155 /* Do not frob unchanging MEMs. If a later reference forces the 3156 pseudo to the stack, we can wind up with multiple writes to 3157 an unchanging memory, which is invalid. */ 3158 if (RTX_UNCHANGING_P (x) && size_x != size_sub) 3159 ; 3160 3161 /* Don't even consider working with paradoxical subregs, 3162 or the moral equivalent seen here. */ 3163 else if (size_x <= size_sub 3164 && int_mode_for_mode (GET_MODE (sub)) != BLKmode) 3165 { 3166 /* Do a bitfield insertion to mirror what would happen 3167 in memory. */ 3168 3169 rtx val, seq; 3170 3171 if (store) 3172 { 3173 rtx p = PREV_INSN (insn); 3174 3175 start_sequence (); 3176 val = gen_reg_rtx (GET_MODE (x)); 3177 if (! validate_change (insn, loc, val, 0)) 3178 { 3179 /* Discard the current sequence and put the 3180 ADDRESSOF on stack. */ 3181 end_sequence (); 3182 goto give_up; 3183 } 3184 seq = get_insns (); 3185 end_sequence (); 3186 emit_insn_before (seq, insn); 3187 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (), 3188 insn, ht); 3189 3190 start_sequence (); 3191 store_bit_field (sub, size_x, 0, GET_MODE (x), 3192 val, GET_MODE_SIZE (GET_MODE (sub))); 3193 3194 /* Make sure to unshare any shared rtl that store_bit_field 3195 might have created. */ 3196 unshare_all_rtl_again (get_insns ()); 3197 3198 seq = get_insns (); 3199 end_sequence (); 3200 p = emit_insn_after (seq, insn); 3201 if (NEXT_INSN (insn)) 3202 compute_insns_for_mem (NEXT_INSN (insn), 3203 p ? NEXT_INSN (p) : NULL_RTX, 3204 ht); 3205 } 3206 else 3207 { 3208 rtx p = PREV_INSN (insn); 3209 3210 start_sequence (); 3211 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX, 3212 GET_MODE (x), GET_MODE (x), 3213 GET_MODE_SIZE (GET_MODE (sub))); 3214 3215 if (! validate_change (insn, loc, val, 0)) 3216 { 3217 /* Discard the current sequence and put the 3218 ADDRESSOF on stack. */ 3219 end_sequence (); 3220 goto give_up; 3221 } 3222 3223 seq = get_insns (); 3224 end_sequence (); 3225 emit_insn_before (seq, insn); 3226 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (), 3227 insn, ht); 3228 } 3229 3230 /* Remember the replacement so that the same one can be done 3231 on the REG_NOTES. */ 3232 purge_bitfield_addressof_replacements 3233 = gen_rtx_EXPR_LIST (VOIDmode, x, 3234 gen_rtx_EXPR_LIST 3235 (VOIDmode, val, 3236 purge_bitfield_addressof_replacements)); 3237 3238 /* We replaced with a reg -- all done. */ 3239 return true; 3240 } 3241 } 3242 3243 else if (validate_change (insn, loc, sub, 0)) 3244 { 3245 /* Remember the replacement so that the same one can be done 3246 on the REG_NOTES. */ 3247 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG) 3248 { 3249 rtx tem; 3250 3251 for (tem = purge_addressof_replacements; 3252 tem != NULL_RTX; 3253 tem = XEXP (XEXP (tem, 1), 1)) 3254 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0))) 3255 { 3256 XEXP (XEXP (tem, 1), 0) = sub; 3257 return true; 3258 } 3259 purge_addressof_replacements 3260 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0), 3261 gen_rtx_EXPR_LIST (VOIDmode, sub, 3262 purge_addressof_replacements)); 3263 return true; 3264 } 3265 goto restart; 3266 } 3267 } 3268 3269 give_up: 3270 /* Scan all subexpressions. */ 3271 fmt = GET_RTX_FORMAT (code); 3272 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++) 3273 { 3274 if (*fmt == 'e') 3275 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, 3276 may_postpone, ht); 3277 else if (*fmt == 'E') 3278 for (j = 0; j < XVECLEN (x, i); j++) 3279 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, 3280 may_postpone, ht); 3281 } 3282 3283 return result; 3284 } 3285 3286 /* Return a hash value for K, a REG. */ 3287 3288 static hashval_t 3289 insns_for_mem_hash (const void *k) 3290 { 3291 /* Use the address of the key for the hash value. */ 3292 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k; 3293 return htab_hash_pointer (m->key); 3294 } 3295 3296 /* Return nonzero if K1 and K2 (two REGs) are the same. */ 3297 3298 static int 3299 insns_for_mem_comp (const void *k1, const void *k2) 3300 { 3301 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1; 3302 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2; 3303 return m1->key == m2->key; 3304 } 3305 3306 struct insns_for_mem_walk_info 3307 { 3308 /* The hash table that we are using to record which INSNs use which 3309 MEMs. */ 3310 htab_t ht; 3311 3312 /* The INSN we are currently processing. */ 3313 rtx insn; 3314 3315 /* Zero if we are walking to find ADDRESSOFs, one if we are walking 3316 to find the insns that use the REGs in the ADDRESSOFs. */ 3317 int pass; 3318 }; 3319 3320 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG 3321 that might be used in an ADDRESSOF expression, record this INSN in 3322 the hash table given by DATA (which is really a pointer to an 3323 insns_for_mem_walk_info structure). */ 3324 3325 static int 3326 insns_for_mem_walk (rtx *r, void *data) 3327 { 3328 struct insns_for_mem_walk_info *ifmwi 3329 = (struct insns_for_mem_walk_info *) data; 3330 struct insns_for_mem_entry tmp; 3331 tmp.insns = NULL_RTX; 3332 3333 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF 3334 && GET_CODE (XEXP (*r, 0)) == REG) 3335 { 3336 void **e; 3337 tmp.key = XEXP (*r, 0); 3338 e = htab_find_slot (ifmwi->ht, &tmp, INSERT); 3339 if (*e == NULL) 3340 { 3341 *e = ggc_alloc (sizeof (tmp)); 3342 memcpy (*e, &tmp, sizeof (tmp)); 3343 } 3344 } 3345 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG) 3346 { 3347 struct insns_for_mem_entry *ifme; 3348 tmp.key = *r; 3349 ifme = htab_find (ifmwi->ht, &tmp); 3350 3351 /* If we have not already recorded this INSN, do so now. Since 3352 we process the INSNs in order, we know that if we have 3353 recorded it it must be at the front of the list. */ 3354 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn)) 3355 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn, 3356 ifme->insns); 3357 } 3358 3359 return 0; 3360 } 3361 3362 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use 3363 which REGs in HT. */ 3364 3365 static void 3366 compute_insns_for_mem (rtx insns, rtx last_insn, htab_t ht) 3367 { 3368 rtx insn; 3369 struct insns_for_mem_walk_info ifmwi; 3370 ifmwi.ht = ht; 3371 3372 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass) 3373 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn)) 3374 if (INSN_P (insn)) 3375 { 3376 ifmwi.insn = insn; 3377 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi); 3378 } 3379 } 3380 3381 /* Helper function for purge_addressof called through for_each_rtx. 3382 Returns true iff the rtl is an ADDRESSOF. */ 3383 3384 static int 3385 is_addressof (rtx *rtl, void *data ATTRIBUTE_UNUSED) 3386 { 3387 return GET_CODE (*rtl) == ADDRESSOF; 3388 } 3389 3390 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining 3391 (MEM (ADDRESSOF)) patterns, and force any needed registers into the 3392 stack. */ 3393 3394 void 3395 purge_addressof (rtx insns) 3396 { 3397 rtx insn, tmp; 3398 htab_t ht; 3399 3400 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That 3401 requires a fixup pass over the instruction stream to correct 3402 INSNs that depended on the REG being a REG, and not a MEM. But, 3403 these fixup passes are slow. Furthermore, most MEMs are not 3404 mentioned in very many instructions. So, we speed up the process 3405 by pre-calculating which REGs occur in which INSNs; that allows 3406 us to perform the fixup passes much more quickly. */ 3407 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL); 3408 compute_insns_for_mem (insns, NULL_RTX, ht); 3409 3410 postponed_insns = NULL; 3411 3412 for (insn = insns; insn; insn = NEXT_INSN (insn)) 3413 if (INSN_P (insn)) 3414 { 3415 if (! purge_addressof_1 (&PATTERN (insn), insn, 3416 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht)) 3417 /* If we could not replace the ADDRESSOFs in the insn, 3418 something is wrong. */ 3419 abort (); 3420 3421 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht)) 3422 { 3423 /* If we could not replace the ADDRESSOFs in the insn's notes, 3424 we can just remove the offending notes instead. */ 3425 rtx note; 3426 3427 for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) 3428 { 3429 /* If we find a REG_RETVAL note then the insn is a libcall. 3430 Such insns must have REG_EQUAL notes as well, in order 3431 for later passes of the compiler to work. So it is not 3432 safe to delete the notes here, and instead we abort. */ 3433 if (REG_NOTE_KIND (note) == REG_RETVAL) 3434 abort (); 3435 if (for_each_rtx (¬e, is_addressof, NULL)) 3436 remove_note (insn, note); 3437 } 3438 } 3439 } 3440 3441 /* Process the postponed insns. */ 3442 while (postponed_insns) 3443 { 3444 insn = XEXP (postponed_insns, 0); 3445 tmp = postponed_insns; 3446 postponed_insns = XEXP (postponed_insns, 1); 3447 free_INSN_LIST_node (tmp); 3448 3449 if (! purge_addressof_1 (&PATTERN (insn), insn, 3450 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht)) 3451 abort (); 3452 } 3453 3454 /* Clean up. */ 3455 purge_bitfield_addressof_replacements = 0; 3456 purge_addressof_replacements = 0; 3457 3458 /* REGs are shared. purge_addressof will destructively replace a REG 3459 with a MEM, which creates shared MEMs. 3460 3461 Unfortunately, the children of put_reg_into_stack assume that MEMs 3462 referring to the same stack slot are shared (fixup_var_refs and 3463 the associated hash table code). 3464 3465 So, we have to do another unsharing pass after we have flushed any 3466 REGs that had their address taken into the stack. 3467 3468 It may be worth tracking whether or not we converted any REGs into 3469 MEMs to avoid this overhead when it is not needed. */ 3470 unshare_all_rtl_again (get_insns ()); 3471 } 3472 3473 /* Convert a SET of a hard subreg to a set of the appropriate hard 3474 register. A subroutine of purge_hard_subreg_sets. */ 3475 3476 static void 3477 purge_single_hard_subreg_set (rtx pattern) 3478 { 3479 rtx reg = SET_DEST (pattern); 3480 enum machine_mode mode = GET_MODE (SET_DEST (pattern)); 3481 int offset = 0; 3482 3483 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG 3484 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER) 3485 { 3486 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)), 3487 GET_MODE (SUBREG_REG (reg)), 3488 SUBREG_BYTE (reg), 3489 GET_MODE (reg)); 3490 reg = SUBREG_REG (reg); 3491 } 3492 3493 3494 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER) 3495 { 3496 reg = gen_rtx_REG (mode, REGNO (reg) + offset); 3497 SET_DEST (pattern) = reg; 3498 } 3499 } 3500 3501 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The 3502 only such SETs that we expect to see are those left in because 3503 integrate can't handle sets of parts of a return value register. 3504 3505 We don't use alter_subreg because we only want to eliminate subregs 3506 of hard registers. */ 3507 3508 void 3509 purge_hard_subreg_sets (rtx insn) 3510 { 3511 for (; insn; insn = NEXT_INSN (insn)) 3512 { 3513 if (INSN_P (insn)) 3514 { 3515 rtx pattern = PATTERN (insn); 3516 switch (GET_CODE (pattern)) 3517 { 3518 case SET: 3519 if (GET_CODE (SET_DEST (pattern)) == SUBREG) 3520 purge_single_hard_subreg_set (pattern); 3521 break; 3522 case PARALLEL: 3523 { 3524 int j; 3525 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--) 3526 { 3527 rtx inner_pattern = XVECEXP (pattern, 0, j); 3528 if (GET_CODE (inner_pattern) == SET 3529 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG) 3530 purge_single_hard_subreg_set (inner_pattern); 3531 } 3532 } 3533 break; 3534 default: 3535 break; 3536 } 3537 } 3538 } 3539 } 3540 3541 /* Pass through the INSNS of function FNDECL and convert virtual register 3542 references to hard register references. */ 3543 3544 void 3545 instantiate_virtual_regs (tree fndecl, rtx insns) 3546 { 3547 rtx insn; 3548 unsigned int i; 3549 3550 /* Compute the offsets to use for this function. */ 3551 in_arg_offset = FIRST_PARM_OFFSET (fndecl); 3552 var_offset = STARTING_FRAME_OFFSET; 3553 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl); 3554 out_arg_offset = STACK_POINTER_OFFSET; 3555 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl); 3556 3557 /* Scan all variables and parameters of this function. For each that is 3558 in memory, instantiate all virtual registers if the result is a valid 3559 address. If not, we do it later. That will handle most uses of virtual 3560 regs on many machines. */ 3561 instantiate_decls (fndecl, 1); 3562 3563 /* Initialize recognition, indicating that volatile is OK. */ 3564 init_recog (); 3565 3566 /* Scan through all the insns, instantiating every virtual register still 3567 present. */ 3568 for (insn = insns; insn; insn = NEXT_INSN (insn)) 3569 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN 3570 || GET_CODE (insn) == CALL_INSN) 3571 { 3572 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1); 3573 if (INSN_DELETED_P (insn)) 3574 continue; 3575 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0); 3576 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */ 3577 if (GET_CODE (insn) == CALL_INSN) 3578 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn), 3579 NULL_RTX, 0); 3580 3581 /* Past this point all ASM statements should match. Verify that 3582 to avoid failures later in the compilation process. */ 3583 if (asm_noperands (PATTERN (insn)) >= 0 3584 && ! check_asm_operands (PATTERN (insn))) 3585 instantiate_virtual_regs_lossage (insn); 3586 } 3587 3588 /* Instantiate the stack slots for the parm registers, for later use in 3589 addressof elimination. */ 3590 for (i = 0; i < max_parm_reg; ++i) 3591 if (parm_reg_stack_loc[i]) 3592 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0); 3593 3594 /* Now instantiate the remaining register equivalences for debugging info. 3595 These will not be valid addresses. */ 3596 instantiate_decls (fndecl, 0); 3597 3598 /* Indicate that, from now on, assign_stack_local should use 3599 frame_pointer_rtx. */ 3600 virtuals_instantiated = 1; 3601 } 3602 3603 /* Scan all decls in FNDECL (both variables and parameters) and instantiate 3604 all virtual registers in their DECL_RTL's. 3605 3606 If VALID_ONLY, do this only if the resulting address is still valid. 3607 Otherwise, always do it. */ 3608 3609 static void 3610 instantiate_decls (tree fndecl, int valid_only) 3611 { 3612 tree decl; 3613 3614 /* Process all parameters of the function. */ 3615 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl)) 3616 { 3617 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl)); 3618 HOST_WIDE_INT size_rtl; 3619 3620 instantiate_decl (DECL_RTL (decl), size, valid_only); 3621 3622 /* If the parameter was promoted, then the incoming RTL mode may be 3623 larger than the declared type size. We must use the larger of 3624 the two sizes. */ 3625 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))); 3626 size = MAX (size_rtl, size); 3627 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only); 3628 } 3629 3630 /* Now process all variables defined in the function or its subblocks. */ 3631 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only); 3632 } 3633 3634 /* Subroutine of instantiate_decls: Process all decls in the given 3635 BLOCK node and all its subblocks. */ 3636 3637 static void 3638 instantiate_decls_1 (tree let, int valid_only) 3639 { 3640 tree t; 3641 3642 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t)) 3643 if (DECL_RTL_SET_P (t)) 3644 instantiate_decl (DECL_RTL (t), 3645 int_size_in_bytes (TREE_TYPE (t)), 3646 valid_only); 3647 3648 /* Process all subblocks. */ 3649 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t)) 3650 instantiate_decls_1 (t, valid_only); 3651 } 3652 3653 /* Subroutine of the preceding procedures: Given RTL representing a 3654 decl and the size of the object, do any instantiation required. 3655 3656 If VALID_ONLY is nonzero, it means that the RTL should only be 3657 changed if the new address is valid. */ 3658 3659 static void 3660 instantiate_decl (rtx x, HOST_WIDE_INT size, int valid_only) 3661 { 3662 enum machine_mode mode; 3663 rtx addr; 3664 3665 if (x == 0) 3666 return; 3667 3668 /* If this is a CONCAT, recurse for the pieces. */ 3669 if (GET_CODE (x) == CONCAT) 3670 { 3671 instantiate_decl (XEXP (x, 0), size / 2, valid_only); 3672 instantiate_decl (XEXP (x, 1), size / 2, valid_only); 3673 return; 3674 } 3675 3676 /* If this is not a MEM, no need to do anything. Similarly if the 3677 address is a constant or a register that is not a virtual register. */ 3678 if (GET_CODE (x) != MEM) 3679 return; 3680 3681 addr = XEXP (x, 0); 3682 if (CONSTANT_P (addr) 3683 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG) 3684 || (GET_CODE (addr) == REG 3685 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER 3686 || REGNO (addr) > LAST_VIRTUAL_REGISTER))) 3687 return; 3688 3689 /* If we should only do this if the address is valid, copy the address. 3690 We need to do this so we can undo any changes that might make the 3691 address invalid. This copy is unfortunate, but probably can't be 3692 avoided. */ 3693 3694 if (valid_only) 3695 addr = copy_rtx (addr); 3696 3697 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0); 3698 3699 if (valid_only && size >= 0) 3700 { 3701 unsigned HOST_WIDE_INT decl_size = size; 3702 3703 /* Now verify that the resulting address is valid for every integer or 3704 floating-point mode up to and including SIZE bytes long. We do this 3705 since the object might be accessed in any mode and frame addresses 3706 are shared. */ 3707 3708 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); 3709 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size; 3710 mode = GET_MODE_WIDER_MODE (mode)) 3711 if (! memory_address_p (mode, addr)) 3712 return; 3713 3714 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT); 3715 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size; 3716 mode = GET_MODE_WIDER_MODE (mode)) 3717 if (! memory_address_p (mode, addr)) 3718 return; 3719 } 3720 3721 /* Put back the address now that we have updated it and we either know 3722 it is valid or we don't care whether it is valid. */ 3723 3724 XEXP (x, 0) = addr; 3725 } 3726 3727 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX 3728 is a virtual register, return the equivalent hard register and set the 3729 offset indirectly through the pointer. Otherwise, return 0. */ 3730 3731 static rtx 3732 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset) 3733 { 3734 rtx new; 3735 HOST_WIDE_INT offset; 3736 3737 if (x == virtual_incoming_args_rtx) 3738 new = arg_pointer_rtx, offset = in_arg_offset; 3739 else if (x == virtual_stack_vars_rtx) 3740 new = frame_pointer_rtx, offset = var_offset; 3741 else if (x == virtual_stack_dynamic_rtx) 3742 new = stack_pointer_rtx, offset = dynamic_offset; 3743 else if (x == virtual_outgoing_args_rtx) 3744 new = stack_pointer_rtx, offset = out_arg_offset; 3745 else if (x == virtual_cfa_rtx) 3746 new = arg_pointer_rtx, offset = cfa_offset; 3747 else 3748 return 0; 3749 3750 *poffset = offset; 3751 return new; 3752 } 3753 3754 3755 /* Called when instantiate_virtual_regs has failed to update the instruction. 3756 Usually this means that non-matching instruction has been emit, however for 3757 asm statements it may be the problem in the constraints. */ 3758 static void 3759 instantiate_virtual_regs_lossage (rtx insn) 3760 { 3761 if (asm_noperands (PATTERN (insn)) >= 0) 3762 { 3763 error_for_asm (insn, "impossible constraint in `asm'"); 3764 delete_insn (insn); 3765 } 3766 else 3767 abort (); 3768 } 3769 /* Given a pointer to a piece of rtx and an optional pointer to the 3770 containing object, instantiate any virtual registers present in it. 3771 3772 If EXTRA_INSNS, we always do the replacement and generate 3773 any extra insns before OBJECT. If it zero, we do nothing if replacement 3774 is not valid. 3775 3776 Return 1 if we either had nothing to do or if we were able to do the 3777 needed replacement. Return 0 otherwise; we only return zero if 3778 EXTRA_INSNS is zero. 3779 3780 We first try some simple transformations to avoid the creation of extra 3781 pseudos. */ 3782 3783 static int 3784 instantiate_virtual_regs_1 (rtx *loc, rtx object, int extra_insns) 3785 { 3786 rtx x; 3787 RTX_CODE code; 3788 rtx new = 0; 3789 HOST_WIDE_INT offset = 0; 3790 rtx temp; 3791 rtx seq; 3792 int i, j; 3793 const char *fmt; 3794 3795 /* Re-start here to avoid recursion in common cases. */ 3796 restart: 3797 3798 x = *loc; 3799 if (x == 0) 3800 return 1; 3801 3802 /* We may have detected and deleted invalid asm statements. */ 3803 if (object && INSN_P (object) && INSN_DELETED_P (object)) 3804 return 1; 3805 3806 code = GET_CODE (x); 3807 3808 /* Check for some special cases. */ 3809 switch (code) 3810 { 3811 case CONST_INT: 3812 case CONST_DOUBLE: 3813 case CONST_VECTOR: 3814 case CONST: 3815 case SYMBOL_REF: 3816 case CODE_LABEL: 3817 case PC: 3818 case CC0: 3819 case ASM_INPUT: 3820 case ADDR_VEC: 3821 case ADDR_DIFF_VEC: 3822 case RETURN: 3823 return 1; 3824 3825 case SET: 3826 /* We are allowed to set the virtual registers. This means that 3827 the actual register should receive the source minus the 3828 appropriate offset. This is used, for example, in the handling 3829 of non-local gotos. */ 3830 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0) 3831 { 3832 rtx src = SET_SRC (x); 3833 3834 /* We are setting the register, not using it, so the relevant 3835 offset is the negative of the offset to use were we using 3836 the register. */ 3837 offset = - offset; 3838 instantiate_virtual_regs_1 (&src, NULL_RTX, 0); 3839 3840 /* The only valid sources here are PLUS or REG. Just do 3841 the simplest possible thing to handle them. */ 3842 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS) 3843 { 3844 instantiate_virtual_regs_lossage (object); 3845 return 1; 3846 } 3847 3848 start_sequence (); 3849 if (GET_CODE (src) != REG) 3850 temp = force_operand (src, NULL_RTX); 3851 else 3852 temp = src; 3853 temp = force_operand (plus_constant (temp, offset), NULL_RTX); 3854 seq = get_insns (); 3855 end_sequence (); 3856 3857 emit_insn_before (seq, object); 3858 SET_DEST (x) = new; 3859 3860 if (! validate_change (object, &SET_SRC (x), temp, 0) 3861 || ! extra_insns) 3862 instantiate_virtual_regs_lossage (object); 3863 3864 return 1; 3865 } 3866 3867 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns); 3868 loc = &SET_SRC (x); 3869 goto restart; 3870 3871 case PLUS: 3872 /* Handle special case of virtual register plus constant. */ 3873 if (CONSTANT_P (XEXP (x, 1))) 3874 { 3875 rtx old, new_offset; 3876 3877 /* Check for (plus (plus VIRT foo) (const_int)) first. */ 3878 if (GET_CODE (XEXP (x, 0)) == PLUS) 3879 { 3880 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset))) 3881 { 3882 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object, 3883 extra_insns); 3884 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1)); 3885 } 3886 else 3887 { 3888 loc = &XEXP (x, 0); 3889 goto restart; 3890 } 3891 } 3892 3893 #ifdef POINTERS_EXTEND_UNSIGNED 3894 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know 3895 we can commute the PLUS and SUBREG because pointers into the 3896 frame are well-behaved. */ 3897 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode 3898 && GET_CODE (XEXP (x, 1)) == CONST_INT 3899 && 0 != (new 3900 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)), 3901 &offset)) 3902 && validate_change (object, loc, 3903 plus_constant (gen_lowpart (ptr_mode, 3904 new), 3905 offset 3906 + INTVAL (XEXP (x, 1))), 3907 0)) 3908 return 1; 3909 #endif 3910 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0) 3911 { 3912 /* We know the second operand is a constant. Unless the 3913 first operand is a REG (which has been already checked), 3914 it needs to be checked. */ 3915 if (GET_CODE (XEXP (x, 0)) != REG) 3916 { 3917 loc = &XEXP (x, 0); 3918 goto restart; 3919 } 3920 return 1; 3921 } 3922 3923 new_offset = plus_constant (XEXP (x, 1), offset); 3924 3925 /* If the new constant is zero, try to replace the sum with just 3926 the register. */ 3927 if (new_offset == const0_rtx 3928 && validate_change (object, loc, new, 0)) 3929 return 1; 3930 3931 /* Next try to replace the register and new offset. 3932 There are two changes to validate here and we can't assume that 3933 in the case of old offset equals new just changing the register 3934 will yield a valid insn. In the interests of a little efficiency, 3935 however, we only call validate change once (we don't queue up the 3936 changes and then call apply_change_group). */ 3937 3938 old = XEXP (x, 0); 3939 if (offset == 0 3940 ? ! validate_change (object, &XEXP (x, 0), new, 0) 3941 : (XEXP (x, 0) = new, 3942 ! validate_change (object, &XEXP (x, 1), new_offset, 0))) 3943 { 3944 if (! extra_insns) 3945 { 3946 XEXP (x, 0) = old; 3947 return 0; 3948 } 3949 3950 /* Otherwise copy the new constant into a register and replace 3951 constant with that register. */ 3952 temp = gen_reg_rtx (Pmode); 3953 XEXP (x, 0) = new; 3954 if (validate_change (object, &XEXP (x, 1), temp, 0)) 3955 emit_insn_before (gen_move_insn (temp, new_offset), object); 3956 else 3957 { 3958 /* If that didn't work, replace this expression with a 3959 register containing the sum. */ 3960 3961 XEXP (x, 0) = old; 3962 new = gen_rtx_PLUS (Pmode, new, new_offset); 3963 3964 start_sequence (); 3965 temp = force_operand (new, NULL_RTX); 3966 seq = get_insns (); 3967 end_sequence (); 3968 3969 emit_insn_before (seq, object); 3970 if (! validate_change (object, loc, temp, 0) 3971 && ! validate_replace_rtx (x, temp, object)) 3972 { 3973 instantiate_virtual_regs_lossage (object); 3974 return 1; 3975 } 3976 } 3977 } 3978 3979 return 1; 3980 } 3981 3982 /* Fall through to generic two-operand expression case. */ 3983 case EXPR_LIST: 3984 case CALL: 3985 case COMPARE: 3986 case MINUS: 3987 case MULT: 3988 case DIV: case UDIV: 3989 case MOD: case UMOD: 3990 case AND: case IOR: case XOR: 3991 case ROTATERT: case ROTATE: 3992 case ASHIFTRT: case LSHIFTRT: case ASHIFT: 3993 case NE: case EQ: 3994 case GE: case GT: case GEU: case GTU: 3995 case LE: case LT: case LEU: case LTU: 3996 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1))) 3997 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns); 3998 loc = &XEXP (x, 0); 3999 goto restart; 4000 4001 case MEM: 4002 /* Most cases of MEM that convert to valid addresses have already been 4003 handled by our scan of decls. The only special handling we 4004 need here is to make a copy of the rtx to ensure it isn't being 4005 shared if we have to change it to a pseudo. 4006 4007 If the rtx is a simple reference to an address via a virtual register, 4008 it can potentially be shared. In such cases, first try to make it 4009 a valid address, which can also be shared. Otherwise, copy it and 4010 proceed normally. 4011 4012 First check for common cases that need no processing. These are 4013 usually due to instantiation already being done on a previous instance 4014 of a shared rtx. */ 4015 4016 temp = XEXP (x, 0); 4017 if (CONSTANT_ADDRESS_P (temp) 4018 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM 4019 || temp == arg_pointer_rtx 4020 #endif 4021 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM 4022 || temp == hard_frame_pointer_rtx 4023 #endif 4024 || temp == frame_pointer_rtx) 4025 return 1; 4026 4027 if (GET_CODE (temp) == PLUS 4028 && CONSTANT_ADDRESS_P (XEXP (temp, 1)) 4029 && (XEXP (temp, 0) == frame_pointer_rtx 4030 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM 4031 || XEXP (temp, 0) == hard_frame_pointer_rtx 4032 #endif 4033 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM 4034 || XEXP (temp, 0) == arg_pointer_rtx 4035 #endif 4036 )) 4037 return 1; 4038 4039 if (temp == virtual_stack_vars_rtx 4040 || temp == virtual_incoming_args_rtx 4041 || (GET_CODE (temp) == PLUS 4042 && CONSTANT_ADDRESS_P (XEXP (temp, 1)) 4043 && (XEXP (temp, 0) == virtual_stack_vars_rtx 4044 || XEXP (temp, 0) == virtual_incoming_args_rtx))) 4045 { 4046 /* This MEM may be shared. If the substitution can be done without 4047 the need to generate new pseudos, we want to do it in place 4048 so all copies of the shared rtx benefit. The call below will 4049 only make substitutions if the resulting address is still 4050 valid. 4051 4052 Note that we cannot pass X as the object in the recursive call 4053 since the insn being processed may not allow all valid 4054 addresses. However, if we were not passed on object, we can 4055 only modify X without copying it if X will have a valid 4056 address. 4057 4058 ??? Also note that this can still lose if OBJECT is an insn that 4059 has less restrictions on an address that some other insn. 4060 In that case, we will modify the shared address. This case 4061 doesn't seem very likely, though. One case where this could 4062 happen is in the case of a USE or CLOBBER reference, but we 4063 take care of that below. */ 4064 4065 if (instantiate_virtual_regs_1 (&XEXP (x, 0), 4066 object ? object : x, 0)) 4067 return 1; 4068 4069 /* Otherwise make a copy and process that copy. We copy the entire 4070 RTL expression since it might be a PLUS which could also be 4071 shared. */ 4072 *loc = x = copy_rtx (x); 4073 } 4074 4075 /* Fall through to generic unary operation case. */ 4076 case PREFETCH: 4077 case SUBREG: 4078 case STRICT_LOW_PART: 4079 case NEG: case NOT: 4080 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC: 4081 case SIGN_EXTEND: case ZERO_EXTEND: 4082 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE: 4083 case FLOAT: case FIX: 4084 case UNSIGNED_FIX: case UNSIGNED_FLOAT: 4085 case ABS: 4086 case SQRT: 4087 case FFS: 4088 case CLZ: case CTZ: 4089 case POPCOUNT: case PARITY: 4090 /* These case either have just one operand or we know that we need not 4091 check the rest of the operands. */ 4092 loc = &XEXP (x, 0); 4093 goto restart; 4094 4095 case USE: 4096 case CLOBBER: 4097 /* If the operand is a MEM, see if the change is a valid MEM. If not, 4098 go ahead and make the invalid one, but do it to a copy. For a REG, 4099 just make the recursive call, since there's no chance of a problem. */ 4100 4101 if ((GET_CODE (XEXP (x, 0)) == MEM 4102 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0), 4103 0)) 4104 || (GET_CODE (XEXP (x, 0)) == REG 4105 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0))) 4106 return 1; 4107 4108 XEXP (x, 0) = copy_rtx (XEXP (x, 0)); 4109 loc = &XEXP (x, 0); 4110 goto restart; 4111 4112 case REG: 4113 /* Try to replace with a PLUS. If that doesn't work, compute the sum 4114 in front of this insn and substitute the temporary. */ 4115 if ((new = instantiate_new_reg (x, &offset)) != 0) 4116 { 4117 temp = plus_constant (new, offset); 4118 if (!validate_change (object, loc, temp, 0)) 4119 { 4120 if (! extra_insns) 4121 return 0; 4122 4123 start_sequence (); 4124 temp = force_operand (temp, NULL_RTX); 4125 seq = get_insns (); 4126 end_sequence (); 4127 4128 emit_insn_before (seq, object); 4129 if (! validate_change (object, loc, temp, 0) 4130 && ! validate_replace_rtx (x, temp, object)) 4131 instantiate_virtual_regs_lossage (object); 4132 } 4133 } 4134 4135 return 1; 4136 4137 case ADDRESSOF: 4138 if (GET_CODE (XEXP (x, 0)) == REG) 4139 return 1; 4140 4141 else if (GET_CODE (XEXP (x, 0)) == MEM) 4142 { 4143 /* If we have a (addressof (mem ..)), do any instantiation inside 4144 since we know we'll be making the inside valid when we finally 4145 remove the ADDRESSOF. */ 4146 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0); 4147 return 1; 4148 } 4149 break; 4150 4151 default: 4152 break; 4153 } 4154 4155 /* Scan all subexpressions. */ 4156 fmt = GET_RTX_FORMAT (code); 4157 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++) 4158 if (*fmt == 'e') 4159 { 4160 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns)) 4161 return 0; 4162 } 4163 else if (*fmt == 'E') 4164 for (j = 0; j < XVECLEN (x, i); j++) 4165 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object, 4166 extra_insns)) 4167 return 0; 4168 4169 return 1; 4170 } 4171 4172 /* Optimization: assuming this function does not receive nonlocal gotos, 4173 delete the handlers for such, as well as the insns to establish 4174 and disestablish them. */ 4175 4176 static void 4177 delete_handlers (void) 4178 { 4179 rtx insn; 4180 for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) 4181 { 4182 /* Delete the handler by turning off the flag that would 4183 prevent jump_optimize from deleting it. 4184 Also permit deletion of the nonlocal labels themselves 4185 if nothing local refers to them. */ 4186 if (GET_CODE (insn) == CODE_LABEL) 4187 { 4188 tree t, last_t; 4189 4190 LABEL_PRESERVE_P (insn) = 0; 4191 4192 /* Remove it from the nonlocal_label list, to avoid confusing 4193 flow. */ 4194 for (t = nonlocal_labels, last_t = 0; t; 4195 last_t = t, t = TREE_CHAIN (t)) 4196 if (DECL_RTL (TREE_VALUE (t)) == insn) 4197 break; 4198 if (t) 4199 { 4200 if (! last_t) 4201 nonlocal_labels = TREE_CHAIN (nonlocal_labels); 4202 else 4203 TREE_CHAIN (last_t) = TREE_CHAIN (t); 4204 } 4205 } 4206 if (GET_CODE (insn) == INSN) 4207 { 4208 int can_delete = 0; 4209 rtx t; 4210 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1)) 4211 if (reg_mentioned_p (t, PATTERN (insn))) 4212 { 4213 can_delete = 1; 4214 break; 4215 } 4216 if (can_delete 4217 || (nonlocal_goto_stack_level != 0 4218 && reg_mentioned_p (nonlocal_goto_stack_level, 4219 PATTERN (insn)))) 4220 delete_related_insns (insn); 4221 } 4222 } 4223 } 4224 4225 /* Return the first insn following those generated by `assign_parms'. */ 4226 4227 rtx 4228 get_first_nonparm_insn (void) 4229 { 4230 if (last_parm_insn) 4231 return NEXT_INSN (last_parm_insn); 4232 return get_insns (); 4233 } 4234 4235 /* Return 1 if EXP is an aggregate type (or a value with aggregate type). 4236 This means a type for which function calls must pass an address to the 4237 function or get an address back from the function. 4238 EXP may be a type node or an expression (whose type is tested). */ 4239 4240 int 4241 aggregate_value_p (tree exp, tree fntype) 4242 { 4243 int i, regno, nregs; 4244 rtx reg; 4245 4246 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp); 4247 4248 if (fntype) 4249 switch (TREE_CODE (fntype)) 4250 { 4251 case CALL_EXPR: 4252 fntype = get_callee_fndecl (fntype); 4253 fntype = fntype ? TREE_TYPE (fntype) : 0; 4254 break; 4255 case FUNCTION_DECL: 4256 fntype = TREE_TYPE (fntype); 4257 break; 4258 case FUNCTION_TYPE: 4259 case METHOD_TYPE: 4260 break; 4261 case IDENTIFIER_NODE: 4262 fntype = 0; 4263 break; 4264 default: 4265 /* We don't expect other rtl types here. */ 4266 abort(); 4267 } 4268 4269 if (TREE_CODE (type) == VOID_TYPE) 4270 return 0; 4271 if (targetm.calls.return_in_memory (type, fntype)) 4272 return 1; 4273 /* Types that are TREE_ADDRESSABLE must be constructed in memory, 4274 and thus can't be returned in registers. */ 4275 if (TREE_ADDRESSABLE (type)) 4276 return 1; 4277 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type)) 4278 return 1; 4279 /* Make sure we have suitable call-clobbered regs to return 4280 the value in; if not, we must return it in memory. */ 4281 reg = hard_function_value (type, 0, 0); 4282 4283 /* If we have something other than a REG (e.g. a PARALLEL), then assume 4284 it is OK. */ 4285 if (GET_CODE (reg) != REG) 4286 return 0; 4287 4288 regno = REGNO (reg); 4289 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type)); 4290 for (i = 0; i < nregs; i++) 4291 if (! call_used_regs[regno + i]) 4292 return 1; 4293 return 0; 4294 } 4295 4296 /* Assign RTL expressions to the function's parameters. 4297 This may involve copying them into registers and using 4298 those registers as the RTL for them. */ 4299 4300 void 4301 assign_parms (tree fndecl) 4302 { 4303 tree parm; 4304 CUMULATIVE_ARGS args_so_far; 4305 /* Total space needed so far for args on the stack, 4306 given as a constant and a tree-expression. */ 4307 struct args_size stack_args_size; 4308 tree fntype = TREE_TYPE (fndecl); 4309 tree fnargs = DECL_ARGUMENTS (fndecl), orig_fnargs; 4310 /* This is used for the arg pointer when referring to stack args. */ 4311 rtx internal_arg_pointer; 4312 /* This is a dummy PARM_DECL that we used for the function result if 4313 the function returns a structure. */ 4314 tree function_result_decl = 0; 4315 int varargs_setup = 0; 4316 int reg_parm_stack_space ATTRIBUTE_UNUSED = 0; 4317 rtx conversion_insns = 0; 4318 4319 /* Nonzero if function takes extra anonymous args. 4320 This means the last named arg must be on the stack 4321 right before the anonymous ones. */ 4322 int stdarg 4323 = (TYPE_ARG_TYPES (fntype) != 0 4324 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype))) 4325 != void_type_node)); 4326 4327 current_function_stdarg = stdarg; 4328 4329 /* If the reg that the virtual arg pointer will be translated into is 4330 not a fixed reg or is the stack pointer, make a copy of the virtual 4331 arg pointer, and address parms via the copy. The frame pointer is 4332 considered fixed even though it is not marked as such. 4333 4334 The second time through, simply use ap to avoid generating rtx. */ 4335 4336 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM 4337 || ! (fixed_regs[ARG_POINTER_REGNUM] 4338 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM))) 4339 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx); 4340 else 4341 internal_arg_pointer = virtual_incoming_args_rtx; 4342 current_function_internal_arg_pointer = internal_arg_pointer; 4343 4344 stack_args_size.constant = 0; 4345 stack_args_size.var = 0; 4346 4347 /* If struct value address is treated as the first argument, make it so. */ 4348 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl) 4349 && ! current_function_returns_pcc_struct 4350 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0) 4351 { 4352 tree type = build_pointer_type (TREE_TYPE (fntype)); 4353 4354 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type); 4355 4356 DECL_ARG_TYPE (function_result_decl) = type; 4357 TREE_CHAIN (function_result_decl) = fnargs; 4358 fnargs = function_result_decl; 4359 } 4360 4361 orig_fnargs = fnargs; 4362 4363 max_parm_reg = LAST_VIRTUAL_REGISTER + 1; 4364 parm_reg_stack_loc = ggc_alloc_cleared (max_parm_reg * sizeof (rtx)); 4365 4366 /* If the target wants to split complex arguments into scalars, do so. */ 4367 if (targetm.calls.split_complex_arg) 4368 fnargs = split_complex_args (fnargs); 4369 4370 #ifdef REG_PARM_STACK_SPACE 4371 #ifdef MAYBE_REG_PARM_STACK_SPACE 4372 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE; 4373 #else 4374 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl); 4375 #endif 4376 #endif 4377 4378 #ifdef INIT_CUMULATIVE_INCOMING_ARGS 4379 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX); 4380 #else 4381 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl, -1); 4382 #endif 4383 4384 /* We haven't yet found an argument that we must push and pretend the 4385 caller did. */ 4386 current_function_pretend_args_size = 0; 4387 4388 for (parm = fnargs; parm; parm = TREE_CHAIN (parm)) 4389 { 4390 rtx entry_parm; 4391 rtx stack_parm; 4392 enum machine_mode promoted_mode, passed_mode; 4393 enum machine_mode nominal_mode, promoted_nominal_mode; 4394 int unsignedp; 4395 struct locate_and_pad_arg_data locate; 4396 int passed_pointer = 0; 4397 int did_conversion = 0; 4398 tree passed_type = DECL_ARG_TYPE (parm); 4399 tree nominal_type = TREE_TYPE (parm); 4400 int last_named = 0, named_arg; 4401 int in_regs; 4402 int partial = 0; 4403 int pretend_bytes = 0; 4404 4405 /* Set LAST_NAMED if this is last named arg before last 4406 anonymous args. */ 4407 if (stdarg) 4408 { 4409 tree tem; 4410 4411 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem)) 4412 if (DECL_NAME (tem)) 4413 break; 4414 4415 if (tem == 0) 4416 last_named = 1; 4417 } 4418 /* Set NAMED_ARG if this arg should be treated as a named arg. For 4419 most machines, if this is a varargs/stdarg function, then we treat 4420 the last named arg as if it were anonymous too. */ 4421 named_arg = targetm.calls.strict_argument_naming (&args_so_far) ? 1 : ! last_named; 4422 4423 if (TREE_TYPE (parm) == error_mark_node 4424 /* This can happen after weird syntax errors 4425 or if an enum type is defined among the parms. */ 4426 || TREE_CODE (parm) != PARM_DECL 4427 || passed_type == NULL) 4428 { 4429 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx)); 4430 DECL_INCOMING_RTL (parm) = DECL_RTL (parm); 4431 TREE_USED (parm) = 1; 4432 continue; 4433 } 4434 4435 /* Find mode of arg as it is passed, and mode of arg 4436 as it should be during execution of this function. */ 4437 passed_mode = TYPE_MODE (passed_type); 4438 nominal_mode = TYPE_MODE (nominal_type); 4439 4440 /* If the parm's mode is VOID, its value doesn't matter, 4441 and avoid the usual things like emit_move_insn that could crash. */ 4442 if (nominal_mode == VOIDmode) 4443 { 4444 SET_DECL_RTL (parm, const0_rtx); 4445 DECL_INCOMING_RTL (parm) = DECL_RTL (parm); 4446 continue; 4447 } 4448 4449 /* If the parm is to be passed as a transparent union, use the 4450 type of the first field for the tests below. We have already 4451 verified that the modes are the same. */ 4452 if (DECL_TRANSPARENT_UNION (parm) 4453 || (TREE_CODE (passed_type) == UNION_TYPE 4454 && TYPE_TRANSPARENT_UNION (passed_type))) 4455 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type)); 4456 4457 /* See if this arg was passed by invisible reference. It is if 4458 it is an object whose size depends on the contents of the 4459 object itself or if the machine requires these objects be passed 4460 that way. */ 4461 4462 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type)) 4463 || TREE_ADDRESSABLE (passed_type) 4464 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE 4465 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode, 4466 passed_type, named_arg) 4467 #endif 4468 ) 4469 { 4470 passed_type = nominal_type = build_pointer_type (passed_type); 4471 passed_pointer = 1; 4472 passed_mode = nominal_mode = Pmode; 4473 } 4474 /* See if the frontend wants to pass this by invisible reference. */ 4475 else if (passed_type != nominal_type 4476 && POINTER_TYPE_P (passed_type) 4477 && TREE_TYPE (passed_type) == nominal_type) 4478 { 4479 nominal_type = passed_type; 4480 passed_pointer = 1; 4481 passed_mode = nominal_mode = Pmode; 4482 } 4483 4484 promoted_mode = passed_mode; 4485 4486 if (targetm.calls.promote_function_args (TREE_TYPE (fndecl))) 4487 { 4488 /* Compute the mode in which the arg is actually extended to. */ 4489 unsignedp = TREE_UNSIGNED (passed_type); 4490 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1); 4491 } 4492 4493 /* Let machine desc say which reg (if any) the parm arrives in. 4494 0 means it arrives on the stack. */ 4495 #ifdef FUNCTION_INCOMING_ARG 4496 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode, 4497 passed_type, named_arg); 4498 #else 4499 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode, 4500 passed_type, named_arg); 4501 #endif 4502 4503 if (entry_parm == 0) 4504 promoted_mode = passed_mode; 4505 4506 /* If this is the last named parameter, do any required setup for 4507 varargs or stdargs. We need to know about the case of this being an 4508 addressable type, in which case we skip the registers it 4509 would have arrived in. 4510 4511 For stdargs, LAST_NAMED will be set for two parameters, the one that 4512 is actually the last named, and the dummy parameter. We only 4513 want to do this action once. 4514 4515 Also, indicate when RTL generation is to be suppressed. */ 4516 if (last_named && !varargs_setup) 4517 { 4518 int varargs_pretend_bytes = 0; 4519 targetm.calls.setup_incoming_varargs (&args_so_far, promoted_mode, 4520 passed_type, 4521 &varargs_pretend_bytes, 0); 4522 varargs_setup = 1; 4523 4524 /* If the back-end has requested extra stack space, record how 4525 much is needed. Do not change pretend_args_size otherwise 4526 since it may be nonzero from an earlier partial argument. */ 4527 if (varargs_pretend_bytes > 0) 4528 current_function_pretend_args_size = varargs_pretend_bytes; 4529 } 4530 4531 /* Determine parm's home in the stack, 4532 in case it arrives in the stack or we should pretend it did. 4533 4534 Compute the stack position and rtx where the argument arrives 4535 and its size. 4536 4537 There is one complexity here: If this was a parameter that would 4538 have been passed in registers, but wasn't only because it is 4539 __builtin_va_alist, we want locate_and_pad_parm to treat it as if 4540 it came in a register so that REG_PARM_STACK_SPACE isn't skipped. 4541 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 4542 0 as it was the previous time. */ 4543 in_regs = entry_parm != 0; 4544 #ifdef STACK_PARMS_IN_REG_PARM_AREA 4545 in_regs = 1; 4546 #endif 4547 if (!in_regs && !named_arg) 4548 { 4549 int pretend_named = 4550 targetm.calls.pretend_outgoing_varargs_named (&args_so_far); 4551 if (pretend_named) 4552 { 4553 #ifdef FUNCTION_INCOMING_ARG 4554 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode, 4555 passed_type, 4556 pretend_named) != 0; 4557 #else 4558 in_regs = FUNCTION_ARG (args_so_far, promoted_mode, 4559 passed_type, 4560 pretend_named) != 0; 4561 #endif 4562 } 4563 } 4564 4565 /* If this parameter was passed both in registers and in the stack, 4566 use the copy on the stack. */ 4567 if (MUST_PASS_IN_STACK (promoted_mode, passed_type)) 4568 entry_parm = 0; 4569 4570 #ifdef FUNCTION_ARG_PARTIAL_NREGS 4571 if (entry_parm) 4572 { 4573 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode, 4574 passed_type, named_arg); 4575 if (partial 4576 #ifndef MAYBE_REG_PARM_STACK_SPACE 4577 /* The caller might already have allocated stack space 4578 for the register parameters. */ 4579 && reg_parm_stack_space == 0 4580 #endif 4581 ) 4582 { 4583 /* Part of this argument is passed in registers and part 4584 is passed on the stack. Ask the prologue code to extend 4585 the stack part so that we can recreate the full value. 4586 4587 PRETEND_BYTES is the size of the registers we need to store. 4588 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra 4589 stack space that the prologue should allocate. 4590 4591 Internally, gcc assumes that the argument pointer is 4592 aligned to STACK_BOUNDARY bits. This is used both for 4593 alignment optimizations (see init_emit) and to locate 4594 arguments that are aligned to more than PARM_BOUNDARY 4595 bits. We must preserve this invariant by rounding 4596 CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to a stack 4597 boundary. */ 4598 pretend_bytes = partial * UNITS_PER_WORD; 4599 current_function_pretend_args_size 4600 = CEIL_ROUND (pretend_bytes, STACK_BYTES); 4601 4602 /* If PRETEND_BYTES != CURRENT_FUNCTION_PRETEND_ARGS_SIZE, 4603 insert the padding before the start of the first pretend 4604 argument. */ 4605 stack_args_size.constant 4606 = (current_function_pretend_args_size - pretend_bytes); 4607 } 4608 } 4609 #endif 4610 4611 memset (&locate, 0, sizeof (locate)); 4612 locate_and_pad_parm (promoted_mode, passed_type, in_regs, 4613 entry_parm ? partial : 0, fndecl, 4614 &stack_args_size, &locate); 4615 4616 { 4617 rtx offset_rtx; 4618 unsigned int align, boundary; 4619 4620 /* If we're passing this arg using a reg, make its stack home 4621 the aligned stack slot. */ 4622 if (entry_parm) 4623 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset); 4624 else 4625 offset_rtx = ARGS_SIZE_RTX (locate.offset); 4626 4627 if (offset_rtx == const0_rtx) 4628 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer); 4629 else 4630 stack_parm = gen_rtx_MEM (promoted_mode, 4631 gen_rtx_PLUS (Pmode, 4632 internal_arg_pointer, 4633 offset_rtx)); 4634 4635 set_mem_attributes (stack_parm, parm, 1); 4636 4637 boundary = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type); 4638 align = 0; 4639 4640 /* If we're padding upward, we know that the alignment of the slot 4641 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're 4642 intentionally forcing upward padding. Otherwise we have to come 4643 up with a guess at the alignment based on OFFSET_RTX. */ 4644 if (locate.where_pad == upward || entry_parm) 4645 align = boundary; 4646 else if (GET_CODE (offset_rtx) == CONST_INT) 4647 { 4648 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary; 4649 align = align & -align; 4650 } 4651 if (align > 0) 4652 set_mem_align (stack_parm, align); 4653 4654 if (entry_parm) 4655 set_reg_attrs_for_parm (entry_parm, stack_parm); 4656 } 4657 4658 /* If this parm was passed part in regs and part in memory, 4659 pretend it arrived entirely in memory 4660 by pushing the register-part onto the stack. 4661 4662 In the special case of a DImode or DFmode that is split, 4663 we could put it together in a pseudoreg directly, 4664 but for now that's not worth bothering with. */ 4665 4666 if (partial) 4667 { 4668 /* Handle calls that pass values in multiple non-contiguous 4669 locations. The Irix 6 ABI has examples of this. */ 4670 if (GET_CODE (entry_parm) == PARALLEL) 4671 emit_group_store (validize_mem (stack_parm), entry_parm, 4672 TREE_TYPE (parm), 4673 int_size_in_bytes (TREE_TYPE (parm))); 4674 4675 else 4676 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm), 4677 partial); 4678 4679 entry_parm = stack_parm; 4680 } 4681 4682 /* If we didn't decide this parm came in a register, 4683 by default it came on the stack. */ 4684 if (entry_parm == 0) 4685 entry_parm = stack_parm; 4686 4687 /* Record permanently how this parm was passed. */ 4688 DECL_INCOMING_RTL (parm) = entry_parm; 4689 4690 /* If there is actually space on the stack for this parm, 4691 count it in stack_args_size; otherwise set stack_parm to 0 4692 to indicate there is no preallocated stack slot for the parm. */ 4693 4694 if (entry_parm == stack_parm 4695 || (GET_CODE (entry_parm) == PARALLEL 4696 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX) 4697 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE) 4698 /* On some machines, even if a parm value arrives in a register 4699 there is still an (uninitialized) stack slot allocated for it. 4700 4701 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell 4702 whether this parameter already has a stack slot allocated, 4703 because an arg block exists only if current_function_args_size 4704 is larger than some threshold, and we haven't calculated that 4705 yet. So, for now, we just assume that stack slots never exist 4706 in this case. */ 4707 || REG_PARM_STACK_SPACE (fndecl) > 0 4708 #endif 4709 ) 4710 { 4711 stack_args_size.constant += pretend_bytes + locate.size.constant; 4712 if (locate.size.var) 4713 ADD_PARM_SIZE (stack_args_size, locate.size.var); 4714 } 4715 else 4716 /* No stack slot was pushed for this parm. */ 4717 stack_parm = 0; 4718 4719 /* Update info on where next arg arrives in registers. */ 4720 4721 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode, 4722 passed_type, named_arg); 4723 4724 /* If we can't trust the parm stack slot to be aligned enough 4725 for its ultimate type, don't use that slot after entry. 4726 We'll make another stack slot, if we need one. */ 4727 if (STRICT_ALIGNMENT && stack_parm 4728 && GET_MODE_ALIGNMENT (nominal_mode) > MEM_ALIGN (stack_parm)) 4729 stack_parm = 0; 4730 4731 /* If parm was passed in memory, and we need to convert it on entry, 4732 don't store it back in that same slot. */ 4733 if (entry_parm == stack_parm 4734 && nominal_mode != BLKmode && nominal_mode != passed_mode) 4735 stack_parm = 0; 4736 4737 /* When an argument is passed in multiple locations, we can't 4738 make use of this information, but we can save some copying if 4739 the whole argument is passed in a single register. */ 4740 if (GET_CODE (entry_parm) == PARALLEL 4741 && nominal_mode != BLKmode && passed_mode != BLKmode) 4742 { 4743 int i, len = XVECLEN (entry_parm, 0); 4744 4745 for (i = 0; i < len; i++) 4746 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX 4747 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG 4748 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) 4749 == passed_mode) 4750 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0) 4751 { 4752 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0); 4753 DECL_INCOMING_RTL (parm) = entry_parm; 4754 break; 4755 } 4756 } 4757 4758 /* ENTRY_PARM is an RTX for the parameter as it arrives, 4759 in the mode in which it arrives. 4760 STACK_PARM is an RTX for a stack slot where the parameter can live 4761 during the function (in case we want to put it there). 4762 STACK_PARM is 0 if no stack slot was pushed for it. 4763 4764 Now output code if necessary to convert ENTRY_PARM to 4765 the type in which this function declares it, 4766 and store that result in an appropriate place, 4767 which may be a pseudo reg, may be STACK_PARM, 4768 or may be a local stack slot if STACK_PARM is 0. 4769 4770 Set DECL_RTL to that place. */ 4771 4772 if (GET_CODE (entry_parm) == PARALLEL && nominal_mode != BLKmode 4773 && XVECLEN (entry_parm, 0) > 1) 4774 { 4775 /* Reconstitute objects the size of a register or larger using 4776 register operations instead of the stack. */ 4777 rtx parmreg = gen_reg_rtx (nominal_mode); 4778 4779 if (REG_P (parmreg)) 4780 { 4781 unsigned int regno = REGNO (parmreg); 4782 4783 emit_group_store (parmreg, entry_parm, TREE_TYPE (parm), 4784 int_size_in_bytes (TREE_TYPE (parm))); 4785 SET_DECL_RTL (parm, parmreg); 4786 4787 if (regno >= max_parm_reg) 4788 { 4789 rtx *new; 4790 int old_max_parm_reg = max_parm_reg; 4791 4792 /* It's slow to expand this one register at a time, 4793 but it's also rare and we need max_parm_reg to be 4794 precisely correct. */ 4795 max_parm_reg = regno + 1; 4796 new = ggc_realloc (parm_reg_stack_loc, 4797 max_parm_reg * sizeof (rtx)); 4798 memset (new + old_max_parm_reg, 0, 4799 (max_parm_reg - old_max_parm_reg) * sizeof (rtx)); 4800 parm_reg_stack_loc = new; 4801 parm_reg_stack_loc[regno] = stack_parm; 4802 } 4803 } 4804 } 4805 4806 if (nominal_mode == BLKmode 4807 #ifdef BLOCK_REG_PADDING 4808 || (locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward) 4809 && GET_MODE_SIZE (promoted_mode) < UNITS_PER_WORD) 4810 #endif 4811 || GET_CODE (entry_parm) == PARALLEL) 4812 { 4813 /* If a BLKmode arrives in registers, copy it to a stack slot. 4814 Handle calls that pass values in multiple non-contiguous 4815 locations. The Irix 6 ABI has examples of this. */ 4816 if (GET_CODE (entry_parm) == REG 4817 || GET_CODE (entry_parm) == PARALLEL) 4818 { 4819 int size = int_size_in_bytes (TREE_TYPE (parm)); 4820 int size_stored = CEIL_ROUND (size, UNITS_PER_WORD); 4821 rtx mem; 4822 4823 /* Note that we will be storing an integral number of words. 4824 So we have to be careful to ensure that we allocate an 4825 integral number of words. We do this below in the 4826 assign_stack_local if space was not allocated in the argument 4827 list. If it was, this will not work if PARM_BOUNDARY is not 4828 a multiple of BITS_PER_WORD. It isn't clear how to fix this 4829 if it becomes a problem. Exception is when BLKmode arrives 4830 with arguments not conforming to word_mode. */ 4831 4832 if (stack_parm == 0) 4833 { 4834 stack_parm = assign_stack_local (BLKmode, size_stored, 0); 4835 PUT_MODE (stack_parm, GET_MODE (entry_parm)); 4836 set_mem_attributes (stack_parm, parm, 1); 4837 } 4838 else if (GET_CODE (entry_parm) == PARALLEL) 4839 ; 4840 else if (PARM_BOUNDARY % BITS_PER_WORD != 0) 4841 abort (); 4842 4843 mem = validize_mem (stack_parm); 4844 4845 /* Handle calls that pass values in multiple non-contiguous 4846 locations. The Irix 6 ABI has examples of this. */ 4847 if (GET_CODE (entry_parm) == PARALLEL) 4848 emit_group_store (mem, entry_parm, TREE_TYPE (parm), size); 4849 4850 else if (size == 0) 4851 ; 4852 4853 /* If SIZE is that of a mode no bigger than a word, just use 4854 that mode's store operation. */ 4855 else if (size <= UNITS_PER_WORD) 4856 { 4857 enum machine_mode mode 4858 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0); 4859 4860 if (mode != BLKmode 4861 #ifdef BLOCK_REG_PADDING 4862 && (size == UNITS_PER_WORD 4863 || (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1) 4864 != (BYTES_BIG_ENDIAN ? upward : downward))) 4865 #endif 4866 ) 4867 { 4868 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm)); 4869 emit_move_insn (change_address (mem, mode, 0), reg); 4870 } 4871 4872 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN 4873 machine must be aligned to the left before storing 4874 to memory. Note that the previous test doesn't 4875 handle all cases (e.g. SIZE == 3). */ 4876 else if (size != UNITS_PER_WORD 4877 #ifdef BLOCK_REG_PADDING 4878 && (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1) 4879 == downward) 4880 #else 4881 && BYTES_BIG_ENDIAN 4882 #endif 4883 ) 4884 { 4885 rtx tem, x; 4886 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT; 4887 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm)); 4888 4889 x = expand_binop (word_mode, ashl_optab, reg, 4890 GEN_INT (by), 0, 1, OPTAB_WIDEN); 4891 tem = change_address (mem, word_mode, 0); 4892 emit_move_insn (tem, x); 4893 } 4894 else 4895 move_block_from_reg (REGNO (entry_parm), mem, 4896 size_stored / UNITS_PER_WORD); 4897 } 4898 else 4899 move_block_from_reg (REGNO (entry_parm), mem, 4900 size_stored / UNITS_PER_WORD); 4901 } 4902 /* If parm is already bound to register pair, don't change 4903 this binding. */ 4904 if (! DECL_RTL_SET_P (parm)) 4905 SET_DECL_RTL (parm, stack_parm); 4906 } 4907 else if (! ((! optimize 4908 && ! DECL_REGISTER (parm)) 4909 || TREE_SIDE_EFFECTS (parm) 4910 /* If -ffloat-store specified, don't put explicit 4911 float variables into registers. */ 4912 || (flag_float_store 4913 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)) 4914 /* Always assign pseudo to structure return or item passed 4915 by invisible reference. */ 4916 || passed_pointer || parm == function_result_decl) 4917 { 4918 /* Store the parm in a pseudoregister during the function, but we 4919 may need to do it in a wider mode. */ 4920 4921 rtx parmreg; 4922 unsigned int regno, regnoi = 0, regnor = 0; 4923 4924 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm)); 4925 4926 promoted_nominal_mode 4927 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0); 4928 4929 parmreg = gen_reg_rtx (promoted_nominal_mode); 4930 mark_user_reg (parmreg); 4931 4932 /* If this was an item that we received a pointer to, set DECL_RTL 4933 appropriately. */ 4934 if (passed_pointer) 4935 { 4936 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)), 4937 parmreg); 4938 set_mem_attributes (x, parm, 1); 4939 SET_DECL_RTL (parm, x); 4940 } 4941 else 4942 { 4943 SET_DECL_RTL (parm, parmreg); 4944 maybe_set_unchanging (DECL_RTL (parm), parm); 4945 } 4946 4947 /* Copy the value into the register. */ 4948 if (nominal_mode != passed_mode 4949 || promoted_nominal_mode != promoted_mode) 4950 { 4951 int save_tree_used; 4952 /* ENTRY_PARM has been converted to PROMOTED_MODE, its 4953 mode, by the caller. We now have to convert it to 4954 NOMINAL_MODE, if different. However, PARMREG may be in 4955 a different mode than NOMINAL_MODE if it is being stored 4956 promoted. 4957 4958 If ENTRY_PARM is a hard register, it might be in a register 4959 not valid for operating in its mode (e.g., an odd-numbered 4960 register for a DFmode). In that case, moves are the only 4961 thing valid, so we can't do a convert from there. This 4962 occurs when the calling sequence allow such misaligned 4963 usages. 4964 4965 In addition, the conversion may involve a call, which could 4966 clobber parameters which haven't been copied to pseudo 4967 registers yet. Therefore, we must first copy the parm to 4968 a pseudo reg here, and save the conversion until after all 4969 parameters have been moved. */ 4970 4971 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm)); 4972 4973 emit_move_insn (tempreg, validize_mem (entry_parm)); 4974 4975 push_to_sequence (conversion_insns); 4976 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp); 4977 4978 if (GET_CODE (tempreg) == SUBREG 4979 && GET_MODE (tempreg) == nominal_mode 4980 && GET_CODE (SUBREG_REG (tempreg)) == REG 4981 && nominal_mode == passed_mode 4982 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm) 4983 && GET_MODE_SIZE (GET_MODE (tempreg)) 4984 < GET_MODE_SIZE (GET_MODE (entry_parm))) 4985 { 4986 /* The argument is already sign/zero extended, so note it 4987 into the subreg. */ 4988 SUBREG_PROMOTED_VAR_P (tempreg) = 1; 4989 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp); 4990 } 4991 4992 /* TREE_USED gets set erroneously during expand_assignment. */ 4993 save_tree_used = TREE_USED (parm); 4994 expand_assignment (parm, 4995 make_tree (nominal_type, tempreg), 0); 4996 TREE_USED (parm) = save_tree_used; 4997 conversion_insns = get_insns (); 4998 did_conversion = 1; 4999 end_sequence (); 5000 } 5001 else 5002 emit_move_insn (parmreg, validize_mem (entry_parm)); 5003 5004 /* If we were passed a pointer but the actual value 5005 can safely live in a register, put it in one. */ 5006 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode 5007 /* If by-reference argument was promoted, demote it. */ 5008 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm)) 5009 || ! ((! optimize 5010 && ! DECL_REGISTER (parm)) 5011 || TREE_SIDE_EFFECTS (parm) 5012 /* If -ffloat-store specified, don't put explicit 5013 float variables into registers. */ 5014 || (flag_float_store 5015 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))) 5016 { 5017 /* We can't use nominal_mode, because it will have been set to 5018 Pmode above. We must use the actual mode of the parm. */ 5019 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm))); 5020 mark_user_reg (parmreg); 5021 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm))) 5022 { 5023 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm))); 5024 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm)); 5025 push_to_sequence (conversion_insns); 5026 emit_move_insn (tempreg, DECL_RTL (parm)); 5027 SET_DECL_RTL (parm, 5028 convert_to_mode (GET_MODE (parmreg), 5029 tempreg, 5030 unsigned_p)); 5031 emit_move_insn (parmreg, DECL_RTL (parm)); 5032 conversion_insns = get_insns(); 5033 did_conversion = 1; 5034 end_sequence (); 5035 } 5036 else 5037 emit_move_insn (parmreg, DECL_RTL (parm)); 5038 SET_DECL_RTL (parm, parmreg); 5039 /* STACK_PARM is the pointer, not the parm, and PARMREG is 5040 now the parm. */ 5041 stack_parm = 0; 5042 } 5043 #ifdef FUNCTION_ARG_CALLEE_COPIES 5044 /* If we are passed an arg by reference and it is our responsibility 5045 to make a copy, do it now. 5046 PASSED_TYPE and PASSED mode now refer to the pointer, not the 5047 original argument, so we must recreate them in the call to 5048 FUNCTION_ARG_CALLEE_COPIES. */ 5049 /* ??? Later add code to handle the case that if the argument isn't 5050 modified, don't do the copy. */ 5051 5052 else if (passed_pointer 5053 && FUNCTION_ARG_CALLEE_COPIES (args_so_far, 5054 TYPE_MODE (TREE_TYPE (passed_type)), 5055 TREE_TYPE (passed_type), 5056 named_arg) 5057 && ! TREE_ADDRESSABLE (TREE_TYPE (passed_type))) 5058 { 5059 rtx copy; 5060 tree type = TREE_TYPE (passed_type); 5061 5062 /* This sequence may involve a library call perhaps clobbering 5063 registers that haven't been copied to pseudos yet. */ 5064 5065 push_to_sequence (conversion_insns); 5066 5067 if (!COMPLETE_TYPE_P (type) 5068 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) 5069 /* This is a variable sized object. */ 5070 copy = gen_rtx_MEM (BLKmode, 5071 allocate_dynamic_stack_space 5072 (expr_size (parm), NULL_RTX, 5073 TYPE_ALIGN (type))); 5074 else 5075 copy = assign_stack_temp (TYPE_MODE (type), 5076 int_size_in_bytes (type), 1); 5077 set_mem_attributes (copy, parm, 1); 5078 5079 store_expr (parm, copy, 0); 5080 emit_move_insn (parmreg, XEXP (copy, 0)); 5081 conversion_insns = get_insns (); 5082 did_conversion = 1; 5083 end_sequence (); 5084 } 5085 #endif /* FUNCTION_ARG_CALLEE_COPIES */ 5086 5087 /* In any case, record the parm's desired stack location 5088 in case we later discover it must live in the stack. 5089 5090 If it is a COMPLEX value, store the stack location for both 5091 halves. */ 5092 5093 if (GET_CODE (parmreg) == CONCAT) 5094 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1))); 5095 else 5096 regno = REGNO (parmreg); 5097 5098 if (regno >= max_parm_reg) 5099 { 5100 rtx *new; 5101 int old_max_parm_reg = max_parm_reg; 5102 5103 /* It's slow to expand this one register at a time, 5104 but it's also rare and we need max_parm_reg to be 5105 precisely correct. */ 5106 max_parm_reg = regno + 1; 5107 new = ggc_realloc (parm_reg_stack_loc, 5108 max_parm_reg * sizeof (rtx)); 5109 memset (new + old_max_parm_reg, 0, 5110 (max_parm_reg - old_max_parm_reg) * sizeof (rtx)); 5111 parm_reg_stack_loc = new; 5112 } 5113 5114 if (GET_CODE (parmreg) == CONCAT) 5115 { 5116 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0)); 5117 5118 regnor = REGNO (gen_realpart (submode, parmreg)); 5119 regnoi = REGNO (gen_imagpart (submode, parmreg)); 5120 5121 if (stack_parm != 0) 5122 { 5123 parm_reg_stack_loc[regnor] 5124 = gen_realpart (submode, stack_parm); 5125 parm_reg_stack_loc[regnoi] 5126 = gen_imagpart (submode, stack_parm); 5127 } 5128 else 5129 { 5130 parm_reg_stack_loc[regnor] = 0; 5131 parm_reg_stack_loc[regnoi] = 0; 5132 } 5133 } 5134 else 5135 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm; 5136 5137 /* Mark the register as eliminable if we did no conversion 5138 and it was copied from memory at a fixed offset, 5139 and the arg pointer was not copied to a pseudo-reg. 5140 If the arg pointer is a pseudo reg or the offset formed 5141 an invalid address, such memory-equivalences 5142 as we make here would screw up life analysis for it. */ 5143 if (nominal_mode == passed_mode 5144 && ! did_conversion 5145 && stack_parm != 0 5146 && GET_CODE (stack_parm) == MEM 5147 && locate.offset.var == 0 5148 && reg_mentioned_p (virtual_incoming_args_rtx, 5149 XEXP (stack_parm, 0))) 5150 { 5151 rtx linsn = get_last_insn (); 5152 rtx sinsn, set; 5153 5154 /* Mark complex types separately. */ 5155 if (GET_CODE (parmreg) == CONCAT) 5156 /* Scan backwards for the set of the real and 5157 imaginary parts. */ 5158 for (sinsn = linsn; sinsn != 0; 5159 sinsn = prev_nonnote_insn (sinsn)) 5160 { 5161 set = single_set (sinsn); 5162 if (set != 0 5163 && SET_DEST (set) == regno_reg_rtx [regnoi]) 5164 REG_NOTES (sinsn) 5165 = gen_rtx_EXPR_LIST (REG_EQUIV, 5166 parm_reg_stack_loc[regnoi], 5167 REG_NOTES (sinsn)); 5168 else if (set != 0 5169 && SET_DEST (set) == regno_reg_rtx [regnor]) 5170 REG_NOTES (sinsn) 5171 = gen_rtx_EXPR_LIST (REG_EQUIV, 5172 parm_reg_stack_loc[regnor], 5173 REG_NOTES (sinsn)); 5174 } 5175 else if ((set = single_set (linsn)) != 0 5176 && SET_DEST (set) == parmreg) 5177 REG_NOTES (linsn) 5178 = gen_rtx_EXPR_LIST (REG_EQUIV, 5179 stack_parm, REG_NOTES (linsn)); 5180 } 5181 5182 /* For pointer data type, suggest pointer register. */ 5183 if (POINTER_TYPE_P (TREE_TYPE (parm))) 5184 mark_reg_pointer (parmreg, 5185 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm)))); 5186 5187 /* If something wants our address, try to use ADDRESSOF. */ 5188 if (TREE_ADDRESSABLE (parm)) 5189 { 5190 /* If we end up putting something into the stack, 5191 fixup_var_refs_insns will need to make a pass over 5192 all the instructions. It looks through the pending 5193 sequences -- but it can't see the ones in the 5194 CONVERSION_INSNS, if they're not on the sequence 5195 stack. So, we go back to that sequence, just so that 5196 the fixups will happen. */ 5197 push_to_sequence (conversion_insns); 5198 put_var_into_stack (parm, /*rescan=*/true); 5199 conversion_insns = get_insns (); 5200 end_sequence (); 5201 } 5202 } 5203 else 5204 { 5205 /* Value must be stored in the stack slot STACK_PARM 5206 during function execution. */ 5207 5208 if (promoted_mode != nominal_mode) 5209 { 5210 /* Conversion is required. */ 5211 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm)); 5212 5213 emit_move_insn (tempreg, validize_mem (entry_parm)); 5214 5215 push_to_sequence (conversion_insns); 5216 entry_parm = convert_to_mode (nominal_mode, tempreg, 5217 TREE_UNSIGNED (TREE_TYPE (parm))); 5218 if (stack_parm) 5219 /* ??? This may need a big-endian conversion on sparc64. */ 5220 stack_parm = adjust_address (stack_parm, nominal_mode, 0); 5221 5222 conversion_insns = get_insns (); 5223 did_conversion = 1; 5224 end_sequence (); 5225 } 5226 5227 if (entry_parm != stack_parm) 5228 { 5229 if (stack_parm == 0) 5230 { 5231 stack_parm 5232 = assign_stack_local (GET_MODE (entry_parm), 5233 GET_MODE_SIZE (GET_MODE (entry_parm)), 5234 0); 5235 set_mem_attributes (stack_parm, parm, 1); 5236 } 5237 5238 if (promoted_mode != nominal_mode) 5239 { 5240 push_to_sequence (conversion_insns); 5241 emit_move_insn (validize_mem (stack_parm), 5242 validize_mem (entry_parm)); 5243 conversion_insns = get_insns (); 5244 end_sequence (); 5245 } 5246 else 5247 emit_move_insn (validize_mem (stack_parm), 5248 validize_mem (entry_parm)); 5249 } 5250 5251 SET_DECL_RTL (parm, stack_parm); 5252 } 5253 } 5254 5255 if (targetm.calls.split_complex_arg && fnargs != orig_fnargs) 5256 { 5257 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm)) 5258 { 5259 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE 5260 && targetm.calls.split_complex_arg (TREE_TYPE (parm))) 5261 { 5262 rtx tmp, real, imag; 5263 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm)); 5264 5265 real = DECL_RTL (fnargs); 5266 imag = DECL_RTL (TREE_CHAIN (fnargs)); 5267 if (inner != GET_MODE (real)) 5268 { 5269 real = gen_lowpart_SUBREG (inner, real); 5270 imag = gen_lowpart_SUBREG (inner, imag); 5271 } 5272 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag); 5273 SET_DECL_RTL (parm, tmp); 5274 5275 real = DECL_INCOMING_RTL (fnargs); 5276 imag = DECL_INCOMING_RTL (TREE_CHAIN (fnargs)); 5277 if (inner != GET_MODE (real)) 5278 { 5279 real = gen_lowpart_SUBREG (inner, real); 5280 imag = gen_lowpart_SUBREG (inner, imag); 5281 } 5282 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag); 5283 DECL_INCOMING_RTL (parm) = tmp; 5284 fnargs = TREE_CHAIN (fnargs); 5285 } 5286 else 5287 { 5288 SET_DECL_RTL (parm, DECL_RTL (fnargs)); 5289 DECL_INCOMING_RTL (parm) = DECL_INCOMING_RTL (fnargs); 5290 } 5291 fnargs = TREE_CHAIN (fnargs); 5292 } 5293 } 5294 5295 /* Output all parameter conversion instructions (possibly including calls) 5296 now that all parameters have been copied out of hard registers. */ 5297 emit_insn (conversion_insns); 5298 5299 /* If we are receiving a struct value address as the first argument, set up 5300 the RTL for the function result. As this might require code to convert 5301 the transmitted address to Pmode, we do this here to ensure that possible 5302 preliminary conversions of the address have been emitted already. */ 5303 if (function_result_decl) 5304 { 5305 tree result = DECL_RESULT (fndecl); 5306 rtx addr = DECL_RTL (function_result_decl); 5307 rtx x; 5308 5309 addr = convert_memory_address (Pmode, addr); 5310 x = gen_rtx_MEM (DECL_MODE (result), addr); 5311 set_mem_attributes (x, result, 1); 5312 SET_DECL_RTL (result, x); 5313 } 5314 5315 last_parm_insn = get_last_insn (); 5316 5317 current_function_args_size = stack_args_size.constant; 5318 5319 /* Adjust function incoming argument size for alignment and 5320 minimum length. */ 5321 5322 #ifdef REG_PARM_STACK_SPACE 5323 #ifndef MAYBE_REG_PARM_STACK_SPACE 5324 current_function_args_size = MAX (current_function_args_size, 5325 REG_PARM_STACK_SPACE (fndecl)); 5326 #endif 5327 #endif 5328 5329 current_function_args_size 5330 = ((current_function_args_size + STACK_BYTES - 1) 5331 / STACK_BYTES) * STACK_BYTES; 5332 5333 #ifdef ARGS_GROW_DOWNWARD 5334 current_function_arg_offset_rtx 5335 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant) 5336 : expand_expr (size_diffop (stack_args_size.var, 5337 size_int (-stack_args_size.constant)), 5338 NULL_RTX, VOIDmode, 0)); 5339 #else 5340 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size); 5341 #endif 5342 5343 /* See how many bytes, if any, of its args a function should try to pop 5344 on return. */ 5345 5346 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl), 5347 current_function_args_size); 5348 5349 /* For stdarg.h function, save info about 5350 regs and stack space used by the named args. */ 5351 5352 current_function_args_info = args_so_far; 5353 5354 /* Set the rtx used for the function return value. Put this in its 5355 own variable so any optimizers that need this information don't have 5356 to include tree.h. Do this here so it gets done when an inlined 5357 function gets output. */ 5358 5359 current_function_return_rtx 5360 = (DECL_RTL_SET_P (DECL_RESULT (fndecl)) 5361 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX); 5362 5363 /* If scalar return value was computed in a pseudo-reg, or was a named 5364 return value that got dumped to the stack, copy that to the hard 5365 return register. */ 5366 if (DECL_RTL_SET_P (DECL_RESULT (fndecl))) 5367 { 5368 tree decl_result = DECL_RESULT (fndecl); 5369 rtx decl_rtl = DECL_RTL (decl_result); 5370 5371 if (REG_P (decl_rtl) 5372 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER 5373 : DECL_REGISTER (decl_result)) 5374 { 5375 rtx real_decl_rtl; 5376 5377 #ifdef FUNCTION_OUTGOING_VALUE 5378 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result), 5379 fndecl); 5380 #else 5381 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result), 5382 fndecl); 5383 #endif 5384 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1; 5385 /* The delay slot scheduler assumes that current_function_return_rtx 5386 holds the hard register containing the return value, not a 5387 temporary pseudo. */ 5388 current_function_return_rtx = real_decl_rtl; 5389 } 5390 } 5391 } 5392 5393 /* If ARGS contains entries with complex types, split the entry into two 5394 entries of the component type. Return a new list of substitutions are 5395 needed, else the old list. */ 5396 5397 static tree 5398 split_complex_args (tree args) 5399 { 5400 tree p; 5401 5402 /* Before allocating memory, check for the common case of no complex. */ 5403 for (p = args; p; p = TREE_CHAIN (p)) 5404 { 5405 tree type = TREE_TYPE (p); 5406 if (TREE_CODE (type) == COMPLEX_TYPE 5407 && targetm.calls.split_complex_arg (type)) 5408 goto found; 5409 } 5410 return args; 5411 5412 found: 5413 args = copy_list (args); 5414 5415 for (p = args; p; p = TREE_CHAIN (p)) 5416 { 5417 tree type = TREE_TYPE (p); 5418 if (TREE_CODE (type) == COMPLEX_TYPE 5419 && targetm.calls.split_complex_arg (type)) 5420 { 5421 tree decl; 5422 tree subtype = TREE_TYPE (type); 5423 5424 /* Rewrite the PARM_DECL's type with its component. */ 5425 TREE_TYPE (p) = subtype; 5426 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p)); 5427 DECL_MODE (p) = VOIDmode; 5428 DECL_SIZE (p) = NULL; 5429 DECL_SIZE_UNIT (p) = NULL; 5430 layout_decl (p, 0); 5431 5432 /* Build a second synthetic decl. */ 5433 decl = build_decl (PARM_DECL, NULL_TREE, subtype); 5434 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p); 5435 layout_decl (decl, 0); 5436 5437 /* Splice it in; skip the new decl. */ 5438 TREE_CHAIN (decl) = TREE_CHAIN (p); 5439 TREE_CHAIN (p) = decl; 5440 p = decl; 5441 } 5442 } 5443 5444 return args; 5445 } 5446 5447 /* Indicate whether REGNO is an incoming argument to the current function 5448 that was promoted to a wider mode. If so, return the RTX for the 5449 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode 5450 that REGNO is promoted from and whether the promotion was signed or 5451 unsigned. */ 5452 5453 rtx 5454 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp) 5455 { 5456 tree arg; 5457 5458 for (arg = DECL_ARGUMENTS (current_function_decl); arg; 5459 arg = TREE_CHAIN (arg)) 5460 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG 5461 && REGNO (DECL_INCOMING_RTL (arg)) == regno 5462 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg))) 5463 { 5464 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg)); 5465 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg)); 5466 5467 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1); 5468 if (mode == GET_MODE (DECL_INCOMING_RTL (arg)) 5469 && mode != DECL_MODE (arg)) 5470 { 5471 *pmode = DECL_MODE (arg); 5472 *punsignedp = unsignedp; 5473 return DECL_INCOMING_RTL (arg); 5474 } 5475 } 5476 5477 return 0; 5478 } 5479 5480 5481 /* Compute the size and offset from the start of the stacked arguments for a 5482 parm passed in mode PASSED_MODE and with type TYPE. 5483 5484 INITIAL_OFFSET_PTR points to the current offset into the stacked 5485 arguments. 5486 5487 The starting offset and size for this parm are returned in 5488 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is 5489 nonzero, the offset is that of stack slot, which is returned in 5490 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of 5491 padding required from the initial offset ptr to the stack slot. 5492 5493 IN_REGS is nonzero if the argument will be passed in registers. It will 5494 never be set if REG_PARM_STACK_SPACE is not defined. 5495 5496 FNDECL is the function in which the argument was defined. 5497 5498 There are two types of rounding that are done. The first, controlled by 5499 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument 5500 list to be aligned to the specific boundary (in bits). This rounding 5501 affects the initial and starting offsets, but not the argument size. 5502 5503 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY, 5504 optionally rounds the size of the parm to PARM_BOUNDARY. The 5505 initial offset is not affected by this rounding, while the size always 5506 is and the starting offset may be. */ 5507 5508 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case; 5509 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's 5510 callers pass in the total size of args so far as 5511 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */ 5512 5513 void 5514 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs, 5515 int partial, tree fndecl ATTRIBUTE_UNUSED, 5516 struct args_size *initial_offset_ptr, 5517 struct locate_and_pad_arg_data *locate) 5518 { 5519 tree sizetree; 5520 enum direction where_pad; 5521 int boundary; 5522 int reg_parm_stack_space = 0; 5523 int part_size_in_regs; 5524 5525 #ifdef REG_PARM_STACK_SPACE 5526 #ifdef MAYBE_REG_PARM_STACK_SPACE 5527 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE; 5528 #else 5529 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl); 5530 #endif 5531 5532 /* If we have found a stack parm before we reach the end of the 5533 area reserved for registers, skip that area. */ 5534 if (! in_regs) 5535 { 5536 if (reg_parm_stack_space > 0) 5537 { 5538 if (initial_offset_ptr->var) 5539 { 5540 initial_offset_ptr->var 5541 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr), 5542 ssize_int (reg_parm_stack_space)); 5543 initial_offset_ptr->constant = 0; 5544 } 5545 else if (initial_offset_ptr->constant < reg_parm_stack_space) 5546 initial_offset_ptr->constant = reg_parm_stack_space; 5547 } 5548 } 5549 #endif /* REG_PARM_STACK_SPACE */ 5550 5551 part_size_in_regs = 0; 5552 if (reg_parm_stack_space == 0) 5553 part_size_in_regs = ((partial * UNITS_PER_WORD) 5554 / (PARM_BOUNDARY / BITS_PER_UNIT) 5555 * (PARM_BOUNDARY / BITS_PER_UNIT)); 5556 5557 sizetree 5558 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode)); 5559 where_pad = FUNCTION_ARG_PADDING (passed_mode, type); 5560 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type); 5561 locate->where_pad = where_pad; 5562 5563 #ifdef ARGS_GROW_DOWNWARD 5564 locate->slot_offset.constant = -initial_offset_ptr->constant; 5565 if (initial_offset_ptr->var) 5566 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0), 5567 initial_offset_ptr->var); 5568 5569 { 5570 tree s2 = sizetree; 5571 if (where_pad != none 5572 && (!host_integerp (sizetree, 1) 5573 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY)) 5574 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT); 5575 SUB_PARM_SIZE (locate->slot_offset, s2); 5576 } 5577 5578 locate->slot_offset.constant += part_size_in_regs; 5579 5580 if (!in_regs 5581 #ifdef REG_PARM_STACK_SPACE 5582 || REG_PARM_STACK_SPACE (fndecl) > 0 5583 #endif 5584 ) 5585 pad_to_arg_alignment (&locate->slot_offset, boundary, 5586 &locate->alignment_pad); 5587 5588 locate->size.constant = (-initial_offset_ptr->constant 5589 - locate->slot_offset.constant); 5590 if (initial_offset_ptr->var) 5591 locate->size.var = size_binop (MINUS_EXPR, 5592 size_binop (MINUS_EXPR, 5593 ssize_int (0), 5594 initial_offset_ptr->var), 5595 locate->slot_offset.var); 5596 5597 /* Pad_below needs the pre-rounded size to know how much to pad 5598 below. */ 5599 locate->offset = locate->slot_offset; 5600 if (where_pad == downward) 5601 pad_below (&locate->offset, passed_mode, sizetree); 5602 5603 #else /* !ARGS_GROW_DOWNWARD */ 5604 if (!in_regs 5605 #ifdef REG_PARM_STACK_SPACE 5606 || REG_PARM_STACK_SPACE (fndecl) > 0 5607 #endif 5608 ) 5609 pad_to_arg_alignment (initial_offset_ptr, boundary, 5610 &locate->alignment_pad); 5611 locate->slot_offset = *initial_offset_ptr; 5612 5613 #ifdef PUSH_ROUNDING 5614 if (passed_mode != BLKmode) 5615 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree))); 5616 #endif 5617 5618 /* Pad_below needs the pre-rounded size to know how much to pad below 5619 so this must be done before rounding up. */ 5620 locate->offset = locate->slot_offset; 5621 if (where_pad == downward) 5622 pad_below (&locate->offset, passed_mode, sizetree); 5623 5624 if (where_pad != none 5625 && (!host_integerp (sizetree, 1) 5626 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY)) 5627 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT); 5628 5629 ADD_PARM_SIZE (locate->size, sizetree); 5630 5631 locate->size.constant -= part_size_in_regs; 5632 #endif /* ARGS_GROW_DOWNWARD */ 5633 } 5634 5635 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY. 5636 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */ 5637 5638 static void 5639 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary, 5640 struct args_size *alignment_pad) 5641 { 5642 tree save_var = NULL_TREE; 5643 HOST_WIDE_INT save_constant = 0; 5644 int boundary_in_bytes = boundary / BITS_PER_UNIT; 5645 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET; 5646 5647 #ifdef SPARC_STACK_BOUNDARY_HACK 5648 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY 5649 higher than the real alignment of %sp. However, when it does this, 5650 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY. 5651 This is a temporary hack while the sparc port is fixed. */ 5652 if (SPARC_STACK_BOUNDARY_HACK) 5653 sp_offset = 0; 5654 #endif 5655 5656 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY) 5657 { 5658 save_var = offset_ptr->var; 5659 save_constant = offset_ptr->constant; 5660 } 5661 5662 alignment_pad->var = NULL_TREE; 5663 alignment_pad->constant = 0; 5664 5665 if (boundary > BITS_PER_UNIT) 5666 { 5667 if (offset_ptr->var) 5668 { 5669 tree sp_offset_tree = ssize_int (sp_offset); 5670 tree offset = size_binop (PLUS_EXPR, 5671 ARGS_SIZE_TREE (*offset_ptr), 5672 sp_offset_tree); 5673 #ifdef ARGS_GROW_DOWNWARD 5674 tree rounded = round_down (offset, boundary / BITS_PER_UNIT); 5675 #else 5676 tree rounded = round_up (offset, boundary / BITS_PER_UNIT); 5677 #endif 5678 5679 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree); 5680 /* ARGS_SIZE_TREE includes constant term. */ 5681 offset_ptr->constant = 0; 5682 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY) 5683 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var, 5684 save_var); 5685 } 5686 else 5687 { 5688 offset_ptr->constant = -sp_offset + 5689 #ifdef ARGS_GROW_DOWNWARD 5690 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes); 5691 #else 5692 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes); 5693 #endif 5694 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY) 5695 alignment_pad->constant = offset_ptr->constant - save_constant; 5696 } 5697 } 5698 } 5699 5700 static void 5701 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree) 5702 { 5703 if (passed_mode != BLKmode) 5704 { 5705 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY) 5706 offset_ptr->constant 5707 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1) 5708 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT) 5709 - GET_MODE_SIZE (passed_mode)); 5710 } 5711 else 5712 { 5713 if (TREE_CODE (sizetree) != INTEGER_CST 5714 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY) 5715 { 5716 /* Round the size up to multiple of PARM_BOUNDARY bits. */ 5717 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT); 5718 /* Add it in. */ 5719 ADD_PARM_SIZE (*offset_ptr, s2); 5720 SUB_PARM_SIZE (*offset_ptr, sizetree); 5721 } 5722 } 5723 } 5724 5725 /* Walk the tree of blocks describing the binding levels within a function 5726 and warn about uninitialized variables. 5727 This is done after calling flow_analysis and before global_alloc 5728 clobbers the pseudo-regs to hard regs. */ 5729 5730 void 5731 uninitialized_vars_warning (tree block) 5732 { 5733 tree decl, sub; 5734 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl)) 5735 { 5736 if (warn_uninitialized 5737 && TREE_CODE (decl) == VAR_DECL 5738 /* These warnings are unreliable for and aggregates 5739 because assigning the fields one by one can fail to convince 5740 flow.c that the entire aggregate was initialized. 5741 Unions are troublesome because members may be shorter. */ 5742 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl)) 5743 && DECL_RTL_SET_P (decl) 5744 && GET_CODE (DECL_RTL (decl)) == REG 5745 /* Global optimizations can make it difficult to determine if a 5746 particular variable has been initialized. However, a VAR_DECL 5747 with a nonzero DECL_INITIAL had an initializer, so do not 5748 claim it is potentially uninitialized. 5749 5750 When the DECL_INITIAL is NULL call the language hook to tell us 5751 if we want to warn. */ 5752 && (DECL_INITIAL (decl) == NULL_TREE || lang_hooks.decl_uninit (decl)) 5753 && regno_uninitialized (REGNO (DECL_RTL (decl)))) 5754 warning ("%J'%D' might be used uninitialized in this function", 5755 decl, decl); 5756 if (extra_warnings 5757 && TREE_CODE (decl) == VAR_DECL 5758 && DECL_RTL_SET_P (decl) 5759 && GET_CODE (DECL_RTL (decl)) == REG 5760 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl)))) 5761 warning ("%Jvariable '%D' might be clobbered by `longjmp' or `vfork'", 5762 decl, decl); 5763 } 5764 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub)) 5765 uninitialized_vars_warning (sub); 5766 } 5767 5768 /* Do the appropriate part of uninitialized_vars_warning 5769 but for arguments instead of local variables. */ 5770 5771 void 5772 setjmp_args_warning (void) 5773 { 5774 tree decl; 5775 for (decl = DECL_ARGUMENTS (current_function_decl); 5776 decl; decl = TREE_CHAIN (decl)) 5777 if (DECL_RTL (decl) != 0 5778 && GET_CODE (DECL_RTL (decl)) == REG 5779 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl)))) 5780 warning ("%Jargument '%D' might be clobbered by `longjmp' or `vfork'", 5781 decl, decl); 5782 } 5783 5784 /* If this function call setjmp, put all vars into the stack 5785 unless they were declared `register'. */ 5786 5787 void 5788 setjmp_protect (tree block) 5789 { 5790 tree decl, sub; 5791 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl)) 5792 if ((TREE_CODE (decl) == VAR_DECL 5793 || TREE_CODE (decl) == PARM_DECL) 5794 && DECL_RTL (decl) != 0 5795 && (GET_CODE (DECL_RTL (decl)) == REG 5796 || (GET_CODE (DECL_RTL (decl)) == MEM 5797 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF)) 5798 /* If this variable came from an inline function, it must be 5799 that its life doesn't overlap the setjmp. If there was a 5800 setjmp in the function, it would already be in memory. We 5801 must exclude such variable because their DECL_RTL might be 5802 set to strange things such as virtual_stack_vars_rtx. */ 5803 && ! DECL_FROM_INLINE (decl) 5804 && ( 5805 #ifdef NON_SAVING_SETJMP 5806 /* If longjmp doesn't restore the registers, 5807 don't put anything in them. */ 5808 NON_SAVING_SETJMP 5809 || 5810 #endif 5811 ! DECL_REGISTER (decl))) 5812 put_var_into_stack (decl, /*rescan=*/true); 5813 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub)) 5814 setjmp_protect (sub); 5815 } 5816 5817 /* Like the previous function, but for args instead of local variables. */ 5818 5819 void 5820 setjmp_protect_args (void) 5821 { 5822 tree decl; 5823 for (decl = DECL_ARGUMENTS (current_function_decl); 5824 decl; decl = TREE_CHAIN (decl)) 5825 if ((TREE_CODE (decl) == VAR_DECL 5826 || TREE_CODE (decl) == PARM_DECL) 5827 && DECL_RTL (decl) != 0 5828 && (GET_CODE (DECL_RTL (decl)) == REG 5829 || (GET_CODE (DECL_RTL (decl)) == MEM 5830 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF)) 5831 && ( 5832 /* If longjmp doesn't restore the registers, 5833 don't put anything in them. */ 5834 #ifdef NON_SAVING_SETJMP 5835 NON_SAVING_SETJMP 5836 || 5837 #endif 5838 ! DECL_REGISTER (decl))) 5839 put_var_into_stack (decl, /*rescan=*/true); 5840 } 5841 5842 /* Return the context-pointer register corresponding to DECL, 5843 or 0 if it does not need one. */ 5844 5845 rtx 5846 lookup_static_chain (tree decl) 5847 { 5848 tree context = decl_function_context (decl); 5849 tree link; 5850 5851 if (context == 0 5852 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl))) 5853 return 0; 5854 5855 /* We treat inline_function_decl as an alias for the current function 5856 because that is the inline function whose vars, types, etc. 5857 are being merged into the current function. 5858 See expand_inline_function. */ 5859 if (context == current_function_decl || context == inline_function_decl) 5860 return virtual_stack_vars_rtx; 5861 5862 for (link = context_display; link; link = TREE_CHAIN (link)) 5863 if (TREE_PURPOSE (link) == context) 5864 return RTL_EXPR_RTL (TREE_VALUE (link)); 5865 5866 abort (); 5867 } 5868 5869 /* Convert a stack slot address ADDR for variable VAR 5870 (from a containing function) 5871 into an address valid in this function (using a static chain). */ 5872 5873 rtx 5874 fix_lexical_addr (rtx addr, tree var) 5875 { 5876 rtx basereg; 5877 HOST_WIDE_INT displacement; 5878 tree context = decl_function_context (var); 5879 struct function *fp; 5880 rtx base = 0; 5881 5882 /* If this is the present function, we need not do anything. */ 5883 if (context == current_function_decl || context == inline_function_decl) 5884 return addr; 5885 5886 fp = find_function_data (context); 5887 5888 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM) 5889 addr = XEXP (XEXP (addr, 0), 0); 5890 5891 /* Decode given address as base reg plus displacement. */ 5892 if (GET_CODE (addr) == REG) 5893 basereg = addr, displacement = 0; 5894 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT) 5895 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1)); 5896 else 5897 abort (); 5898 5899 /* We accept vars reached via the containing function's 5900 incoming arg pointer and via its stack variables pointer. */ 5901 if (basereg == fp->internal_arg_pointer) 5902 { 5903 /* If reached via arg pointer, get the arg pointer value 5904 out of that function's stack frame. 5905 5906 There are two cases: If a separate ap is needed, allocate a 5907 slot in the outer function for it and dereference it that way. 5908 This is correct even if the real ap is actually a pseudo. 5909 Otherwise, just adjust the offset from the frame pointer to 5910 compensate. */ 5911 5912 #ifdef NEED_SEPARATE_AP 5913 rtx addr; 5914 5915 addr = get_arg_pointer_save_area (fp); 5916 addr = fix_lexical_addr (XEXP (addr, 0), var); 5917 addr = memory_address (Pmode, addr); 5918 5919 base = gen_rtx_MEM (Pmode, addr); 5920 set_mem_alias_set (base, get_frame_alias_set ()); 5921 base = copy_to_reg (base); 5922 #else 5923 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET); 5924 base = lookup_static_chain (var); 5925 #endif 5926 } 5927 5928 else if (basereg == virtual_stack_vars_rtx) 5929 { 5930 /* This is the same code as lookup_static_chain, duplicated here to 5931 avoid an extra call to decl_function_context. */ 5932 tree link; 5933 5934 for (link = context_display; link; link = TREE_CHAIN (link)) 5935 if (TREE_PURPOSE (link) == context) 5936 { 5937 base = RTL_EXPR_RTL (TREE_VALUE (link)); 5938 break; 5939 } 5940 } 5941 5942 if (base == 0) 5943 abort (); 5944 5945 /* Use same offset, relative to appropriate static chain or argument 5946 pointer. */ 5947 return plus_constant (base, displacement); 5948 } 5949 5950 /* Return the address of the trampoline for entering nested fn FUNCTION. 5951 If necessary, allocate a trampoline (in the stack frame) 5952 and emit rtl to initialize its contents (at entry to this function). */ 5953 5954 rtx 5955 trampoline_address (tree function) 5956 { 5957 tree link; 5958 tree rtlexp; 5959 rtx tramp; 5960 struct function *fp; 5961 tree fn_context; 5962 5963 /* Find an existing trampoline and return it. */ 5964 for (link = trampoline_list; link; link = TREE_CHAIN (link)) 5965 if (TREE_PURPOSE (link) == function) 5966 return 5967 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0)); 5968 5969 for (fp = outer_function_chain; fp; fp = fp->outer) 5970 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link)) 5971 if (TREE_PURPOSE (link) == function) 5972 { 5973 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0), 5974 function); 5975 return adjust_trampoline_addr (tramp); 5976 } 5977 5978 /* None exists; we must make one. */ 5979 5980 /* Find the `struct function' for the function containing FUNCTION. */ 5981 fp = 0; 5982 fn_context = decl_function_context (function); 5983 if (fn_context != current_function_decl 5984 && fn_context != inline_function_decl) 5985 fp = find_function_data (fn_context); 5986 5987 /* Allocate run-time space for this trampoline. */ 5988 /* If rounding needed, allocate extra space 5989 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */ 5990 #define TRAMPOLINE_REAL_SIZE \ 5991 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1) 5992 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0, 5993 fp ? fp : cfun); 5994 /* Record the trampoline for reuse and note it for later initialization 5995 by expand_function_end. */ 5996 if (fp != 0) 5997 { 5998 rtlexp = make_node (RTL_EXPR); 5999 RTL_EXPR_RTL (rtlexp) = tramp; 6000 fp->x_trampoline_list = tree_cons (function, rtlexp, 6001 fp->x_trampoline_list); 6002 } 6003 else 6004 { 6005 /* Make the RTL_EXPR node temporary, not momentary, so that the 6006 trampoline_list doesn't become garbage. */ 6007 rtlexp = make_node (RTL_EXPR); 6008 6009 RTL_EXPR_RTL (rtlexp) = tramp; 6010 trampoline_list = tree_cons (function, rtlexp, trampoline_list); 6011 } 6012 6013 tramp = fix_lexical_addr (XEXP (tramp, 0), function); 6014 return adjust_trampoline_addr (tramp); 6015 } 6016 6017 /* Given a trampoline address, 6018 round it to multiple of TRAMPOLINE_ALIGNMENT. */ 6019 6020 static rtx 6021 round_trampoline_addr (rtx tramp) 6022 { 6023 /* Round address up to desired boundary. */ 6024 rtx temp = gen_reg_rtx (Pmode); 6025 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1); 6026 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT); 6027 6028 temp = expand_simple_binop (Pmode, PLUS, tramp, addend, 6029 temp, 0, OPTAB_LIB_WIDEN); 6030 tramp = expand_simple_binop (Pmode, AND, temp, mask, 6031 temp, 0, OPTAB_LIB_WIDEN); 6032 6033 return tramp; 6034 } 6035 6036 /* Given a trampoline address, round it then apply any 6037 platform-specific adjustments so that the result can be used for a 6038 function call . */ 6039 6040 static rtx 6041 adjust_trampoline_addr (rtx tramp) 6042 { 6043 tramp = round_trampoline_addr (tramp); 6044 #ifdef TRAMPOLINE_ADJUST_ADDRESS 6045 TRAMPOLINE_ADJUST_ADDRESS (tramp); 6046 #endif 6047 return tramp; 6048 } 6049 6050 /* Put all this function's BLOCK nodes including those that are chained 6051 onto the first block into a vector, and return it. 6052 Also store in each NOTE for the beginning or end of a block 6053 the index of that block in the vector. 6054 The arguments are BLOCK, the chain of top-level blocks of the function, 6055 and INSNS, the insn chain of the function. */ 6056 6057 void 6058 identify_blocks (void) 6059 { 6060 int n_blocks; 6061 tree *block_vector, *last_block_vector; 6062 tree *block_stack; 6063 tree block = DECL_INITIAL (current_function_decl); 6064 6065 if (block == 0) 6066 return; 6067 6068 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in 6069 depth-first order. */ 6070 block_vector = get_block_vector (block, &n_blocks); 6071 block_stack = xmalloc (n_blocks * sizeof (tree)); 6072 6073 last_block_vector = identify_blocks_1 (get_insns (), 6074 block_vector + 1, 6075 block_vector + n_blocks, 6076 block_stack); 6077 6078 /* If we didn't use all of the subblocks, we've misplaced block notes. */ 6079 /* ??? This appears to happen all the time. Latent bugs elsewhere? */ 6080 if (0 && last_block_vector != block_vector + n_blocks) 6081 abort (); 6082 6083 free (block_vector); 6084 free (block_stack); 6085 } 6086 6087 /* Subroutine of identify_blocks. Do the block substitution on the 6088 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains. 6089 6090 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair. 6091 BLOCK_VECTOR is incremented for each block seen. */ 6092 6093 static tree * 6094 identify_blocks_1 (rtx insns, tree *block_vector, tree *end_block_vector, 6095 tree *orig_block_stack) 6096 { 6097 rtx insn; 6098 tree *block_stack = orig_block_stack; 6099 6100 for (insn = insns; insn; insn = NEXT_INSN (insn)) 6101 { 6102 if (GET_CODE (insn) == NOTE) 6103 { 6104 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG) 6105 { 6106 tree b; 6107 6108 /* If there are more block notes than BLOCKs, something 6109 is badly wrong. */ 6110 if (block_vector == end_block_vector) 6111 abort (); 6112 6113 b = *block_vector++; 6114 NOTE_BLOCK (insn) = b; 6115 *block_stack++ = b; 6116 } 6117 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END) 6118 { 6119 /* If there are more NOTE_INSN_BLOCK_ENDs than 6120 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */ 6121 if (block_stack == orig_block_stack) 6122 abort (); 6123 6124 NOTE_BLOCK (insn) = *--block_stack; 6125 } 6126 } 6127 else if (GET_CODE (insn) == CALL_INSN 6128 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER) 6129 { 6130 rtx cp = PATTERN (insn); 6131 6132 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector, 6133 end_block_vector, block_stack); 6134 if (XEXP (cp, 1)) 6135 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector, 6136 end_block_vector, block_stack); 6137 if (XEXP (cp, 2)) 6138 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector, 6139 end_block_vector, block_stack); 6140 } 6141 } 6142 6143 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs, 6144 something is badly wrong. */ 6145 if (block_stack != orig_block_stack) 6146 abort (); 6147 6148 return block_vector; 6149 } 6150 6151 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END}, 6152 and create duplicate blocks. */ 6153 /* ??? Need an option to either create block fragments or to create 6154 abstract origin duplicates of a source block. It really depends 6155 on what optimization has been performed. */ 6156 6157 void 6158 reorder_blocks (void) 6159 { 6160 tree block = DECL_INITIAL (current_function_decl); 6161 varray_type block_stack; 6162 6163 if (block == NULL_TREE) 6164 return; 6165 6166 VARRAY_TREE_INIT (block_stack, 10, "block_stack"); 6167 6168 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */ 6169 reorder_blocks_0 (block); 6170 6171 /* Prune the old trees away, so that they don't get in the way. */ 6172 BLOCK_SUBBLOCKS (block) = NULL_TREE; 6173 BLOCK_CHAIN (block) = NULL_TREE; 6174 6175 /* Recreate the block tree from the note nesting. */ 6176 reorder_blocks_1 (get_insns (), block, &block_stack); 6177 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block)); 6178 6179 /* Remove deleted blocks from the block fragment chains. */ 6180 reorder_fix_fragments (block); 6181 } 6182 6183 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */ 6184 6185 static void 6186 reorder_blocks_0 (tree block) 6187 { 6188 while (block) 6189 { 6190 TREE_ASM_WRITTEN (block) = 0; 6191 reorder_blocks_0 (BLOCK_SUBBLOCKS (block)); 6192 block = BLOCK_CHAIN (block); 6193 } 6194 } 6195 6196 static void 6197 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack) 6198 { 6199 rtx insn; 6200 6201 for (insn = insns; insn; insn = NEXT_INSN (insn)) 6202 { 6203 if (GET_CODE (insn) == NOTE) 6204 { 6205 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG) 6206 { 6207 tree block = NOTE_BLOCK (insn); 6208 6209 /* If we have seen this block before, that means it now 6210 spans multiple address regions. Create a new fragment. */ 6211 if (TREE_ASM_WRITTEN (block)) 6212 { 6213 tree new_block = copy_node (block); 6214 tree origin; 6215 6216 origin = (BLOCK_FRAGMENT_ORIGIN (block) 6217 ? BLOCK_FRAGMENT_ORIGIN (block) 6218 : block); 6219 BLOCK_FRAGMENT_ORIGIN (new_block) = origin; 6220 BLOCK_FRAGMENT_CHAIN (new_block) 6221 = BLOCK_FRAGMENT_CHAIN (origin); 6222 BLOCK_FRAGMENT_CHAIN (origin) = new_block; 6223 6224 NOTE_BLOCK (insn) = new_block; 6225 block = new_block; 6226 } 6227 6228 BLOCK_SUBBLOCKS (block) = 0; 6229 TREE_ASM_WRITTEN (block) = 1; 6230 /* When there's only one block for the entire function, 6231 current_block == block and we mustn't do this, it 6232 will cause infinite recursion. */ 6233 if (block != current_block) 6234 { 6235 BLOCK_SUPERCONTEXT (block) = current_block; 6236 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block); 6237 BLOCK_SUBBLOCKS (current_block) = block; 6238 current_block = block; 6239 } 6240 VARRAY_PUSH_TREE (*p_block_stack, block); 6241 } 6242 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END) 6243 { 6244 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack); 6245 VARRAY_POP (*p_block_stack); 6246 BLOCK_SUBBLOCKS (current_block) 6247 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block)); 6248 current_block = BLOCK_SUPERCONTEXT (current_block); 6249 } 6250 } 6251 else if (GET_CODE (insn) == CALL_INSN 6252 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER) 6253 { 6254 rtx cp = PATTERN (insn); 6255 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack); 6256 if (XEXP (cp, 1)) 6257 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack); 6258 if (XEXP (cp, 2)) 6259 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack); 6260 } 6261 } 6262 } 6263 6264 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer 6265 appears in the block tree, select one of the fragments to become 6266 the new origin block. */ 6267 6268 static void 6269 reorder_fix_fragments (tree block) 6270 { 6271 while (block) 6272 { 6273 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block); 6274 tree new_origin = NULL_TREE; 6275 6276 if (dup_origin) 6277 { 6278 if (! TREE_ASM_WRITTEN (dup_origin)) 6279 { 6280 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin); 6281 6282 /* Find the first of the remaining fragments. There must 6283 be at least one -- the current block. */ 6284 while (! TREE_ASM_WRITTEN (new_origin)) 6285 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin); 6286 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE; 6287 } 6288 } 6289 else if (! dup_origin) 6290 new_origin = block; 6291 6292 /* Re-root the rest of the fragments to the new origin. In the 6293 case that DUP_ORIGIN was null, that means BLOCK was the origin 6294 of a chain of fragments and we want to remove those fragments 6295 that didn't make it to the output. */ 6296 if (new_origin) 6297 { 6298 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin); 6299 tree chain = *pp; 6300 6301 while (chain) 6302 { 6303 if (TREE_ASM_WRITTEN (chain)) 6304 { 6305 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin; 6306 *pp = chain; 6307 pp = &BLOCK_FRAGMENT_CHAIN (chain); 6308 } 6309 chain = BLOCK_FRAGMENT_CHAIN (chain); 6310 } 6311 *pp = NULL_TREE; 6312 } 6313 6314 reorder_fix_fragments (BLOCK_SUBBLOCKS (block)); 6315 block = BLOCK_CHAIN (block); 6316 } 6317 } 6318 6319 /* Reverse the order of elements in the chain T of blocks, 6320 and return the new head of the chain (old last element). */ 6321 6322 static tree 6323 blocks_nreverse (tree t) 6324 { 6325 tree prev = 0, decl, next; 6326 for (decl = t; decl; decl = next) 6327 { 6328 next = BLOCK_CHAIN (decl); 6329 BLOCK_CHAIN (decl) = prev; 6330 prev = decl; 6331 } 6332 return prev; 6333 } 6334 6335 /* Count the subblocks of the list starting with BLOCK. If VECTOR is 6336 non-NULL, list them all into VECTOR, in a depth-first preorder 6337 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all 6338 blocks. */ 6339 6340 static int 6341 all_blocks (tree block, tree *vector) 6342 { 6343 int n_blocks = 0; 6344 6345 while (block) 6346 { 6347 TREE_ASM_WRITTEN (block) = 0; 6348 6349 /* Record this block. */ 6350 if (vector) 6351 vector[n_blocks] = block; 6352 6353 ++n_blocks; 6354 6355 /* Record the subblocks, and their subblocks... */ 6356 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block), 6357 vector ? vector + n_blocks : 0); 6358 block = BLOCK_CHAIN (block); 6359 } 6360 6361 return n_blocks; 6362 } 6363 6364 /* Return a vector containing all the blocks rooted at BLOCK. The 6365 number of elements in the vector is stored in N_BLOCKS_P. The 6366 vector is dynamically allocated; it is the caller's responsibility 6367 to call `free' on the pointer returned. */ 6368 6369 static tree * 6370 get_block_vector (tree block, int *n_blocks_p) 6371 { 6372 tree *block_vector; 6373 6374 *n_blocks_p = all_blocks (block, NULL); 6375 block_vector = xmalloc (*n_blocks_p * sizeof (tree)); 6376 all_blocks (block, block_vector); 6377 6378 return block_vector; 6379 } 6380 6381 static GTY(()) int next_block_index = 2; 6382 6383 /* Set BLOCK_NUMBER for all the blocks in FN. */ 6384 6385 void 6386 number_blocks (tree fn) 6387 { 6388 int i; 6389 int n_blocks; 6390 tree *block_vector; 6391 6392 /* For SDB and XCOFF debugging output, we start numbering the blocks 6393 from 1 within each function, rather than keeping a running 6394 count. */ 6395 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO) 6396 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG) 6397 next_block_index = 1; 6398 #endif 6399 6400 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks); 6401 6402 /* The top-level BLOCK isn't numbered at all. */ 6403 for (i = 1; i < n_blocks; ++i) 6404 /* We number the blocks from two. */ 6405 BLOCK_NUMBER (block_vector[i]) = next_block_index++; 6406 6407 free (block_vector); 6408 6409 return; 6410 } 6411 6412 /* If VAR is present in a subblock of BLOCK, return the subblock. */ 6413 6414 tree 6415 debug_find_var_in_block_tree (tree var, tree block) 6416 { 6417 tree t; 6418 6419 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t)) 6420 if (t == var) 6421 return block; 6422 6423 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t)) 6424 { 6425 tree ret = debug_find_var_in_block_tree (var, t); 6426 if (ret) 6427 return ret; 6428 } 6429 6430 return NULL_TREE; 6431 } 6432 6433 /* Allocate a function structure for FNDECL and set its contents 6434 to the defaults. */ 6435 6436 void 6437 allocate_struct_function (tree fndecl) 6438 { 6439 tree result; 6440 6441 cfun = ggc_alloc_cleared (sizeof (struct function)); 6442 6443 max_parm_reg = LAST_VIRTUAL_REGISTER + 1; 6444 6445 cfun->stack_alignment_needed = STACK_BOUNDARY; 6446 cfun->preferred_stack_boundary = STACK_BOUNDARY; 6447 6448 current_function_funcdef_no = funcdef_no++; 6449 6450 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL; 6451 6452 init_stmt_for_function (); 6453 init_eh_for_function (); 6454 6455 (*lang_hooks.function.init) (cfun); 6456 if (init_machine_status) 6457 cfun->machine = (*init_machine_status) (); 6458 6459 if (fndecl == NULL) 6460 return; 6461 6462 DECL_SAVED_INSNS (fndecl) = cfun; 6463 cfun->decl = fndecl; 6464 6465 result = DECL_RESULT (fndecl); 6466 if (aggregate_value_p (result, fndecl)) 6467 { 6468 #ifdef PCC_STATIC_STRUCT_RETURN 6469 current_function_returns_pcc_struct = 1; 6470 #endif 6471 current_function_returns_struct = 1; 6472 } 6473 6474 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result)); 6475 6476 current_function_needs_context 6477 = (decl_function_context (current_function_decl) != 0 6478 && ! DECL_NO_STATIC_CHAIN (current_function_decl)); 6479 } 6480 6481 /* Reset cfun, and other non-struct-function variables to defaults as 6482 appropriate for emitting rtl at the start of a function. */ 6483 6484 static void 6485 prepare_function_start (tree fndecl) 6486 { 6487 if (fndecl && DECL_SAVED_INSNS (fndecl)) 6488 cfun = DECL_SAVED_INSNS (fndecl); 6489 else 6490 allocate_struct_function (fndecl); 6491 init_emit (); 6492 init_varasm_status (cfun); 6493 init_expr (); 6494 6495 cse_not_expected = ! optimize; 6496 6497 /* Caller save not needed yet. */ 6498 caller_save_needed = 0; 6499 6500 /* We haven't done register allocation yet. */ 6501 reg_renumber = 0; 6502 6503 /* Indicate that we need to distinguish between the return value of the 6504 present function and the return value of a function being called. */ 6505 rtx_equal_function_value_matters = 1; 6506 6507 /* Indicate that we have not instantiated virtual registers yet. */ 6508 virtuals_instantiated = 0; 6509 6510 /* Indicate that we want CONCATs now. */ 6511 generating_concat_p = 1; 6512 6513 /* Indicate we have no need of a frame pointer yet. */ 6514 frame_pointer_needed = 0; 6515 } 6516 6517 /* Initialize the rtl expansion mechanism so that we can do simple things 6518 like generate sequences. This is used to provide a context during global 6519 initialization of some passes. */ 6520 void 6521 init_dummy_function_start (void) 6522 { 6523 prepare_function_start (NULL); 6524 } 6525 6526 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node) 6527 and initialize static variables for generating RTL for the statements 6528 of the function. */ 6529 6530 void 6531 init_function_start (tree subr) 6532 { 6533 prepare_function_start (subr); 6534 6535 /* Within function body, compute a type's size as soon it is laid out. */ 6536 immediate_size_expand++; 6537 6538 /* Prevent ever trying to delete the first instruction of a 6539 function. Also tell final how to output a linenum before the 6540 function prologue. Note linenums could be missing, e.g. when 6541 compiling a Java .class file. */ 6542 if (DECL_SOURCE_LINE (subr)) 6543 emit_line_note (DECL_SOURCE_LOCATION (subr)); 6544 6545 /* Make sure first insn is a note even if we don't want linenums. 6546 This makes sure the first insn will never be deleted. 6547 Also, final expects a note to appear there. */ 6548 emit_note (NOTE_INSN_DELETED); 6549 6550 /* Warn if this value is an aggregate type, 6551 regardless of which calling convention we are using for it. */ 6552 if (warn_aggregate_return 6553 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr)))) 6554 warning ("function returns an aggregate"); 6555 } 6556 6557 /* Make sure all values used by the optimization passes have sane 6558 defaults. */ 6559 void 6560 init_function_for_compilation (void) 6561 { 6562 reg_renumber = 0; 6563 6564 /* No prologue/epilogue insns yet. */ 6565 VARRAY_GROW (prologue, 0); 6566 VARRAY_GROW (epilogue, 0); 6567 VARRAY_GROW (sibcall_epilogue, 0); 6568 } 6569 6570 /* Expand a call to __main at the beginning of a possible main function. */ 6571 6572 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main) 6573 #undef HAS_INIT_SECTION 6574 #define HAS_INIT_SECTION 6575 #endif 6576 6577 void 6578 expand_main_function (void) 6579 { 6580 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN 6581 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN) 6582 { 6583 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT; 6584 rtx tmp, seq; 6585 6586 start_sequence (); 6587 /* Forcibly align the stack. */ 6588 #ifdef STACK_GROWS_DOWNWARD 6589 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align), 6590 stack_pointer_rtx, 1, OPTAB_WIDEN); 6591 #else 6592 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx, 6593 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN); 6594 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align), 6595 stack_pointer_rtx, 1, OPTAB_WIDEN); 6596 #endif 6597 if (tmp != stack_pointer_rtx) 6598 emit_move_insn (stack_pointer_rtx, tmp); 6599 6600 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */ 6601 tmp = force_reg (Pmode, const0_rtx); 6602 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT); 6603 seq = get_insns (); 6604 end_sequence (); 6605 6606 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp)) 6607 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG) 6608 break; 6609 if (tmp) 6610 emit_insn_before (seq, tmp); 6611 else 6612 emit_insn (seq); 6613 } 6614 #endif 6615 6616 #ifndef HAS_INIT_SECTION 6617 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0); 6618 #endif 6619 } 6620 6621 /* The PENDING_SIZES represent the sizes of variable-sized types. 6622 Create RTL for the various sizes now (using temporary variables), 6623 so that we can refer to the sizes from the RTL we are generating 6624 for the current function. The PENDING_SIZES are a TREE_LIST. The 6625 TREE_VALUE of each node is a SAVE_EXPR. */ 6626 6627 void 6628 expand_pending_sizes (tree pending_sizes) 6629 { 6630 tree tem; 6631 6632 /* Evaluate now the sizes of any types declared among the arguments. */ 6633 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem)) 6634 { 6635 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0); 6636 /* Flush the queue in case this parameter declaration has 6637 side-effects. */ 6638 emit_queue (); 6639 } 6640 } 6641 6642 /* Start the RTL for a new function, and set variables used for 6643 emitting RTL. 6644 SUBR is the FUNCTION_DECL node. 6645 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with 6646 the function's parameters, which must be run at any return statement. */ 6647 6648 void 6649 expand_function_start (tree subr, int parms_have_cleanups) 6650 { 6651 tree tem; 6652 rtx last_ptr = NULL_RTX; 6653 6654 /* Make sure volatile mem refs aren't considered 6655 valid operands of arithmetic insns. */ 6656 init_recog_no_volatile (); 6657 6658 current_function_instrument_entry_exit 6659 = (flag_instrument_function_entry_exit 6660 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr)); 6661 6662 current_function_profile 6663 = (profile_flag 6664 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr)); 6665 6666 current_function_limit_stack 6667 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr)); 6668 6669 /* If function gets a static chain arg, store it in the stack frame. 6670 Do this first, so it gets the first stack slot offset. */ 6671 if (current_function_needs_context) 6672 { 6673 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0); 6674 6675 /* Delay copying static chain if it is not a register to avoid 6676 conflicts with regs used for parameters. */ 6677 if (! SMALL_REGISTER_CLASSES 6678 || GET_CODE (static_chain_incoming_rtx) == REG) 6679 emit_move_insn (last_ptr, static_chain_incoming_rtx); 6680 } 6681 6682 /* If the parameters of this function need cleaning up, get a label 6683 for the beginning of the code which executes those cleanups. This must 6684 be done before doing anything with return_label. */ 6685 if (parms_have_cleanups) 6686 cleanup_label = gen_label_rtx (); 6687 else 6688 cleanup_label = 0; 6689 6690 /* Make the label for return statements to jump to. Do not special 6691 case machines with special return instructions -- they will be 6692 handled later during jump, ifcvt, or epilogue creation. */ 6693 return_label = gen_label_rtx (); 6694 6695 /* Initialize rtx used to return the value. */ 6696 /* Do this before assign_parms so that we copy the struct value address 6697 before any library calls that assign parms might generate. */ 6698 6699 /* Decide whether to return the value in memory or in a register. */ 6700 if (aggregate_value_p (DECL_RESULT (subr), subr)) 6701 { 6702 /* Returning something that won't go in a register. */ 6703 rtx value_address = 0; 6704 6705 #ifdef PCC_STATIC_STRUCT_RETURN 6706 if (current_function_returns_pcc_struct) 6707 { 6708 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr))); 6709 value_address = assemble_static_space (size); 6710 } 6711 else 6712 #endif 6713 { 6714 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1); 6715 /* Expect to be passed the address of a place to store the value. 6716 If it is passed as an argument, assign_parms will take care of 6717 it. */ 6718 if (sv) 6719 { 6720 value_address = gen_reg_rtx (Pmode); 6721 emit_move_insn (value_address, sv); 6722 } 6723 } 6724 if (value_address) 6725 { 6726 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address); 6727 set_mem_attributes (x, DECL_RESULT (subr), 1); 6728 SET_DECL_RTL (DECL_RESULT (subr), x); 6729 } 6730 } 6731 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode) 6732 /* If return mode is void, this decl rtl should not be used. */ 6733 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX); 6734 else 6735 { 6736 /* Compute the return values into a pseudo reg, which we will copy 6737 into the true return register after the cleanups are done. */ 6738 6739 /* In order to figure out what mode to use for the pseudo, we 6740 figure out what the mode of the eventual return register will 6741 actually be, and use that. */ 6742 rtx hard_reg 6743 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)), 6744 subr, 1); 6745 6746 /* Structures that are returned in registers are not aggregate_value_p, 6747 so we may see a PARALLEL or a REG. */ 6748 if (REG_P (hard_reg)) 6749 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg))); 6750 else if (GET_CODE (hard_reg) == PARALLEL) 6751 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg)); 6752 else 6753 abort (); 6754 6755 /* Set DECL_REGISTER flag so that expand_function_end will copy the 6756 result to the real return register(s). */ 6757 DECL_REGISTER (DECL_RESULT (subr)) = 1; 6758 } 6759 6760 /* Initialize rtx for parameters and local variables. 6761 In some cases this requires emitting insns. */ 6762 6763 assign_parms (subr); 6764 6765 /* Copy the static chain now if it wasn't a register. The delay is to 6766 avoid conflicts with the parameter passing registers. */ 6767 6768 if (SMALL_REGISTER_CLASSES && current_function_needs_context) 6769 if (GET_CODE (static_chain_incoming_rtx) != REG) 6770 emit_move_insn (last_ptr, static_chain_incoming_rtx); 6771 6772 /* The following was moved from init_function_start. 6773 The move is supposed to make sdb output more accurate. */ 6774 /* Indicate the beginning of the function body, 6775 as opposed to parm setup. */ 6776 emit_note (NOTE_INSN_FUNCTION_BEG); 6777 6778 if (GET_CODE (get_last_insn ()) != NOTE) 6779 emit_note (NOTE_INSN_DELETED); 6780 parm_birth_insn = get_last_insn (); 6781 6782 context_display = 0; 6783 if (current_function_needs_context) 6784 { 6785 /* Fetch static chain values for containing functions. */ 6786 tem = decl_function_context (current_function_decl); 6787 /* Copy the static chain pointer into a pseudo. If we have 6788 small register classes, copy the value from memory if 6789 static_chain_incoming_rtx is a REG. */ 6790 if (tem) 6791 { 6792 /* If the static chain originally came in a register, put it back 6793 there, then move it out in the next insn. The reason for 6794 this peculiar code is to satisfy function integration. */ 6795 if (SMALL_REGISTER_CLASSES 6796 && GET_CODE (static_chain_incoming_rtx) == REG) 6797 emit_move_insn (static_chain_incoming_rtx, last_ptr); 6798 last_ptr = copy_to_reg (static_chain_incoming_rtx); 6799 } 6800 6801 while (tem) 6802 { 6803 tree rtlexp = make_node (RTL_EXPR); 6804 6805 RTL_EXPR_RTL (rtlexp) = last_ptr; 6806 context_display = tree_cons (tem, rtlexp, context_display); 6807 tem = decl_function_context (tem); 6808 if (tem == 0) 6809 break; 6810 /* Chain through stack frames, assuming pointer to next lexical frame 6811 is found at the place we always store it. */ 6812 #ifdef FRAME_GROWS_DOWNWARD 6813 last_ptr = plus_constant (last_ptr, 6814 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode)); 6815 #endif 6816 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr)); 6817 set_mem_alias_set (last_ptr, get_frame_alias_set ()); 6818 last_ptr = copy_to_reg (last_ptr); 6819 6820 /* If we are not optimizing, ensure that we know that this 6821 piece of context is live over the entire function. */ 6822 if (! optimize) 6823 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr, 6824 save_expr_regs); 6825 } 6826 } 6827 6828 if (current_function_instrument_entry_exit) 6829 { 6830 rtx fun = DECL_RTL (current_function_decl); 6831 if (GET_CODE (fun) == MEM) 6832 fun = XEXP (fun, 0); 6833 else 6834 abort (); 6835 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode, 6836 2, fun, Pmode, 6837 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS, 6838 0, 6839 hard_frame_pointer_rtx), 6840 Pmode); 6841 } 6842 6843 if (current_function_profile) 6844 { 6845 #ifdef PROFILE_HOOK 6846 PROFILE_HOOK (current_function_funcdef_no); 6847 #endif 6848 } 6849 6850 /* After the display initializations is where the tail-recursion label 6851 should go, if we end up needing one. Ensure we have a NOTE here 6852 since some things (like trampolines) get placed before this. */ 6853 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED); 6854 6855 /* Evaluate now the sizes of any types declared among the arguments. */ 6856 expand_pending_sizes (nreverse (get_pending_sizes ())); 6857 6858 /* Make sure there is a line number after the function entry setup code. */ 6859 force_next_line_note (); 6860 } 6861 6862 /* Undo the effects of init_dummy_function_start. */ 6863 void 6864 expand_dummy_function_end (void) 6865 { 6866 /* End any sequences that failed to be closed due to syntax errors. */ 6867 while (in_sequence_p ()) 6868 end_sequence (); 6869 6870 /* Outside function body, can't compute type's actual size 6871 until next function's body starts. */ 6872 6873 free_after_parsing (cfun); 6874 free_after_compilation (cfun); 6875 cfun = 0; 6876 } 6877 6878 /* Call DOIT for each hard register used as a return value from 6879 the current function. */ 6880 6881 void 6882 diddle_return_value (void (*doit) (rtx, void *), void *arg) 6883 { 6884 rtx outgoing = current_function_return_rtx; 6885 6886 if (! outgoing) 6887 return; 6888 6889 if (GET_CODE (outgoing) == REG) 6890 (*doit) (outgoing, arg); 6891 else if (GET_CODE (outgoing) == PARALLEL) 6892 { 6893 int i; 6894 6895 for (i = 0; i < XVECLEN (outgoing, 0); i++) 6896 { 6897 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0); 6898 6899 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER) 6900 (*doit) (x, arg); 6901 } 6902 } 6903 } 6904 6905 static void 6906 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED) 6907 { 6908 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg)); 6909 } 6910 6911 void 6912 clobber_return_register (void) 6913 { 6914 diddle_return_value (do_clobber_return_reg, NULL); 6915 6916 /* In case we do use pseudo to return value, clobber it too. */ 6917 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl))) 6918 { 6919 tree decl_result = DECL_RESULT (current_function_decl); 6920 rtx decl_rtl = DECL_RTL (decl_result); 6921 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER) 6922 { 6923 do_clobber_return_reg (decl_rtl, NULL); 6924 } 6925 } 6926 } 6927 6928 static void 6929 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED) 6930 { 6931 emit_insn (gen_rtx_USE (VOIDmode, reg)); 6932 } 6933 6934 void 6935 use_return_register (void) 6936 { 6937 diddle_return_value (do_use_return_reg, NULL); 6938 } 6939 6940 /* Possibly warn about unused parameters. */ 6941 void 6942 do_warn_unused_parameter (tree fn) 6943 { 6944 tree decl; 6945 6946 for (decl = DECL_ARGUMENTS (fn); 6947 decl; decl = TREE_CHAIN (decl)) 6948 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL 6949 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)) 6950 warning ("%Junused parameter '%D'", decl, decl); 6951 } 6952 6953 static GTY(()) rtx initial_trampoline; 6954 6955 /* Generate RTL for the end of the current function. */ 6956 6957 void 6958 expand_function_end (void) 6959 { 6960 tree link; 6961 rtx clobber_after; 6962 6963 finish_expr_for_function (); 6964 6965 /* If arg_pointer_save_area was referenced only from a nested 6966 function, we will not have initialized it yet. Do that now. */ 6967 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init) 6968 get_arg_pointer_save_area (cfun); 6969 6970 #ifdef NON_SAVING_SETJMP 6971 /* Don't put any variables in registers if we call setjmp 6972 on a machine that fails to restore the registers. */ 6973 if (NON_SAVING_SETJMP && current_function_calls_setjmp) 6974 { 6975 if (DECL_INITIAL (current_function_decl) != error_mark_node) 6976 setjmp_protect (DECL_INITIAL (current_function_decl)); 6977 6978 setjmp_protect_args (); 6979 } 6980 #endif 6981 6982 /* Initialize any trampolines required by this function. */ 6983 for (link = trampoline_list; link; link = TREE_CHAIN (link)) 6984 { 6985 tree function = TREE_PURPOSE (link); 6986 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function); 6987 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link)); 6988 #ifdef TRAMPOLINE_TEMPLATE 6989 rtx blktramp; 6990 #endif 6991 rtx seq; 6992 6993 #ifdef TRAMPOLINE_TEMPLATE 6994 /* First make sure this compilation has a template for 6995 initializing trampolines. */ 6996 if (initial_trampoline == 0) 6997 { 6998 initial_trampoline 6999 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ()); 7000 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT); 7001 } 7002 #endif 7003 7004 /* Generate insns to initialize the trampoline. */ 7005 start_sequence (); 7006 tramp = round_trampoline_addr (XEXP (tramp, 0)); 7007 #ifdef TRAMPOLINE_TEMPLATE 7008 blktramp = replace_equiv_address (initial_trampoline, tramp); 7009 emit_block_move (blktramp, initial_trampoline, 7010 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL); 7011 #endif 7012 trampolines_created = 1; 7013 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context); 7014 seq = get_insns (); 7015 end_sequence (); 7016 7017 /* Put those insns at entry to the containing function (this one). */ 7018 emit_insn_before (seq, tail_recursion_reentry); 7019 } 7020 7021 /* If we are doing stack checking and this function makes calls, 7022 do a stack probe at the start of the function to ensure we have enough 7023 space for another stack frame. */ 7024 if (flag_stack_check && ! STACK_CHECK_BUILTIN) 7025 { 7026 rtx insn, seq; 7027 7028 for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) 7029 if (GET_CODE (insn) == CALL_INSN) 7030 { 7031 start_sequence (); 7032 probe_stack_range (STACK_CHECK_PROTECT, 7033 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE)); 7034 seq = get_insns (); 7035 end_sequence (); 7036 emit_insn_before (seq, tail_recursion_reentry); 7037 break; 7038 } 7039 } 7040 7041 /* Possibly warn about unused parameters. 7042 When frontend does unit-at-a-time, the warning is already 7043 issued at finalization time. */ 7044 if (warn_unused_parameter 7045 && !lang_hooks.callgraph.expand_function) 7046 do_warn_unused_parameter (current_function_decl); 7047 7048 /* Delete handlers for nonlocal gotos if nothing uses them. */ 7049 if (nonlocal_goto_handler_slots != 0 7050 && ! current_function_has_nonlocal_label) 7051 delete_handlers (); 7052 7053 /* End any sequences that failed to be closed due to syntax errors. */ 7054 while (in_sequence_p ()) 7055 end_sequence (); 7056 7057 /* Outside function body, can't compute type's actual size 7058 until next function's body starts. */ 7059 immediate_size_expand--; 7060 7061 clear_pending_stack_adjust (); 7062 do_pending_stack_adjust (); 7063 7064 /* ??? This is a kludge. We want to ensure that instructions that 7065 may trap are not moved into the epilogue by scheduling, because 7066 we don't always emit unwind information for the epilogue. 7067 However, not all machine descriptions define a blockage insn, so 7068 emit an ASM_INPUT to act as one. */ 7069 if (flag_non_call_exceptions) 7070 emit_insn (gen_rtx_ASM_INPUT (VOIDmode, "")); 7071 7072 /* Mark the end of the function body. 7073 If control reaches this insn, the function can drop through 7074 without returning a value. */ 7075 emit_note (NOTE_INSN_FUNCTION_END); 7076 7077 /* Must mark the last line number note in the function, so that the test 7078 coverage code can avoid counting the last line twice. This just tells 7079 the code to ignore the immediately following line note, since there 7080 already exists a copy of this note somewhere above. This line number 7081 note is still needed for debugging though, so we can't delete it. */ 7082 if (flag_test_coverage) 7083 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER); 7084 7085 /* Output a linenumber for the end of the function. 7086 SDB depends on this. */ 7087 force_next_line_note (); 7088 emit_line_note (input_location); 7089 7090 /* Before the return label (if any), clobber the return 7091 registers so that they are not propagated live to the rest of 7092 the function. This can only happen with functions that drop 7093 through; if there had been a return statement, there would 7094 have either been a return rtx, or a jump to the return label. 7095 7096 We delay actual code generation after the current_function_value_rtx 7097 is computed. */ 7098 clobber_after = get_last_insn (); 7099 7100 /* Output the label for the actual return from the function, 7101 if one is expected. This happens either because a function epilogue 7102 is used instead of a return instruction, or because a return was done 7103 with a goto in order to run local cleanups, or because of pcc-style 7104 structure returning. */ 7105 if (return_label) 7106 emit_label (return_label); 7107 7108 if (current_function_instrument_entry_exit) 7109 { 7110 rtx fun = DECL_RTL (current_function_decl); 7111 if (GET_CODE (fun) == MEM) 7112 fun = XEXP (fun, 0); 7113 else 7114 abort (); 7115 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode, 7116 2, fun, Pmode, 7117 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS, 7118 0, 7119 hard_frame_pointer_rtx), 7120 Pmode); 7121 } 7122 7123 #ifdef TARGET_PROFILER_EPILOGUE 7124 if (current_function_profile && TARGET_PROFILER_EPILOGUE) 7125 { 7126 static rtx mexitcount_libfunc; 7127 static int initialized; 7128 7129 if (!initialized) 7130 { 7131 mexitcount_libfunc = init_one_libfunc (".mexitcount"); 7132 initialized = 1; 7133 } 7134 emit_library_call (mexitcount_libfunc, LCT_NORMAL, VOIDmode, 0); 7135 } 7136 #endif 7137 7138 /* Let except.c know where it should emit the call to unregister 7139 the function context for sjlj exceptions. */ 7140 if (flag_exceptions && USING_SJLJ_EXCEPTIONS) 7141 sjlj_emit_function_exit_after (get_last_insn ()); 7142 7143 /* If we had calls to alloca, and this machine needs 7144 an accurate stack pointer to exit the function, 7145 insert some code to save and restore the stack pointer. */ 7146 if (! EXIT_IGNORE_STACK 7147 && current_function_calls_alloca) 7148 { 7149 rtx tem = 0; 7150 7151 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn); 7152 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX); 7153 } 7154 7155 /* If scalar return value was computed in a pseudo-reg, or was a named 7156 return value that got dumped to the stack, copy that to the hard 7157 return register. */ 7158 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl))) 7159 { 7160 tree decl_result = DECL_RESULT (current_function_decl); 7161 rtx decl_rtl = DECL_RTL (decl_result); 7162 7163 if (REG_P (decl_rtl) 7164 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER 7165 : DECL_REGISTER (decl_result)) 7166 { 7167 rtx real_decl_rtl = current_function_return_rtx; 7168 7169 /* This should be set in assign_parms. */ 7170 if (! REG_FUNCTION_VALUE_P (real_decl_rtl)) 7171 abort (); 7172 7173 /* If this is a BLKmode structure being returned in registers, 7174 then use the mode computed in expand_return. Note that if 7175 decl_rtl is memory, then its mode may have been changed, 7176 but that current_function_return_rtx has not. */ 7177 if (GET_MODE (real_decl_rtl) == BLKmode) 7178 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl)); 7179 7180 /* If a named return value dumped decl_return to memory, then 7181 we may need to re-do the PROMOTE_MODE signed/unsigned 7182 extension. */ 7183 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl)) 7184 { 7185 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result)); 7186 7187 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl))) 7188 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl), 7189 &unsignedp, 1); 7190 7191 convert_move (real_decl_rtl, decl_rtl, unsignedp); 7192 } 7193 else if (GET_CODE (real_decl_rtl) == PARALLEL) 7194 { 7195 /* If expand_function_start has created a PARALLEL for decl_rtl, 7196 move the result to the real return registers. Otherwise, do 7197 a group load from decl_rtl for a named return. */ 7198 if (GET_CODE (decl_rtl) == PARALLEL) 7199 emit_group_move (real_decl_rtl, decl_rtl); 7200 else 7201 emit_group_load (real_decl_rtl, decl_rtl, 7202 TREE_TYPE (decl_result), 7203 int_size_in_bytes (TREE_TYPE (decl_result))); 7204 } 7205 else 7206 emit_move_insn (real_decl_rtl, decl_rtl); 7207 } 7208 } 7209 7210 /* If returning a structure, arrange to return the address of the value 7211 in a place where debuggers expect to find it. 7212 7213 If returning a structure PCC style, 7214 the caller also depends on this value. 7215 And current_function_returns_pcc_struct is not necessarily set. */ 7216 if (current_function_returns_struct 7217 || current_function_returns_pcc_struct) 7218 { 7219 rtx value_address 7220 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0); 7221 tree type = TREE_TYPE (DECL_RESULT (current_function_decl)); 7222 #ifdef FUNCTION_OUTGOING_VALUE 7223 rtx outgoing 7224 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type), 7225 current_function_decl); 7226 #else 7227 rtx outgoing 7228 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl); 7229 #endif 7230 7231 /* Mark this as a function return value so integrate will delete the 7232 assignment and USE below when inlining this function. */ 7233 REG_FUNCTION_VALUE_P (outgoing) = 1; 7234 7235 /* The address may be ptr_mode and OUTGOING may be Pmode. */ 7236 value_address = convert_memory_address (GET_MODE (outgoing), 7237 value_address); 7238 7239 emit_move_insn (outgoing, value_address); 7240 7241 /* Show return register used to hold result (in this case the address 7242 of the result. */ 7243 current_function_return_rtx = outgoing; 7244 } 7245 7246 /* If this is an implementation of throw, do what's necessary to 7247 communicate between __builtin_eh_return and the epilogue. */ 7248 expand_eh_return (); 7249 7250 /* Emit the actual code to clobber return register. */ 7251 { 7252 rtx seq, after; 7253 7254 start_sequence (); 7255 clobber_return_register (); 7256 seq = get_insns (); 7257 end_sequence (); 7258 7259 after = emit_insn_after (seq, clobber_after); 7260 7261 if (clobber_after != after) 7262 cfun->x_clobber_return_insn = after; 7263 } 7264 7265 /* Output the label for the naked return from the function, if one is 7266 expected. This is currently used only by __builtin_return. */ 7267 if (naked_return_label) 7268 emit_label (naked_return_label); 7269 7270 /* ??? This should no longer be necessary since stupid is no longer with 7271 us, but there are some parts of the compiler (eg reload_combine, and 7272 sh mach_dep_reorg) that still try and compute their own lifetime info 7273 instead of using the general framework. */ 7274 use_return_register (); 7275 7276 /* Fix up any gotos that jumped out to the outermost 7277 binding level of the function. 7278 Must follow emitting RETURN_LABEL. */ 7279 7280 /* If you have any cleanups to do at this point, 7281 and they need to create temporary variables, 7282 then you will lose. */ 7283 expand_fixups (get_insns ()); 7284 } 7285 7286 rtx 7287 get_arg_pointer_save_area (struct function *f) 7288 { 7289 rtx ret = f->x_arg_pointer_save_area; 7290 7291 if (! ret) 7292 { 7293 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f); 7294 f->x_arg_pointer_save_area = ret; 7295 } 7296 7297 if (f == cfun && ! f->arg_pointer_save_area_init) 7298 { 7299 rtx seq; 7300 7301 /* Save the arg pointer at the beginning of the function. The 7302 generated stack slot may not be a valid memory address, so we 7303 have to check it and fix it if necessary. */ 7304 start_sequence (); 7305 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx); 7306 seq = get_insns (); 7307 end_sequence (); 7308 7309 push_topmost_sequence (); 7310 emit_insn_after (seq, get_insns ()); 7311 pop_topmost_sequence (); 7312 } 7313 7314 return ret; 7315 } 7316 7317 /* Extend a vector that records the INSN_UIDs of INSNS 7318 (a list of one or more insns). */ 7319 7320 static void 7321 record_insns (rtx insns, varray_type *vecp) 7322 { 7323 int i, len; 7324 rtx tmp; 7325 7326 tmp = insns; 7327 len = 0; 7328 while (tmp != NULL_RTX) 7329 { 7330 len++; 7331 tmp = NEXT_INSN (tmp); 7332 } 7333 7334 i = VARRAY_SIZE (*vecp); 7335 VARRAY_GROW (*vecp, i + len); 7336 tmp = insns; 7337 while (tmp != NULL_RTX) 7338 { 7339 VARRAY_INT (*vecp, i) = INSN_UID (tmp); 7340 i++; 7341 tmp = NEXT_INSN (tmp); 7342 } 7343 } 7344 7345 /* Set the locator of the insn chain starting at INSN to LOC. */ 7346 static void 7347 set_insn_locators (rtx insn, int loc) 7348 { 7349 while (insn != NULL_RTX) 7350 { 7351 if (INSN_P (insn)) 7352 INSN_LOCATOR (insn) = loc; 7353 insn = NEXT_INSN (insn); 7354 } 7355 } 7356 7357 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can 7358 be running after reorg, SEQUENCE rtl is possible. */ 7359 7360 static int 7361 contains (rtx insn, varray_type vec) 7362 { 7363 int i, j; 7364 7365 if (GET_CODE (insn) == INSN 7366 && GET_CODE (PATTERN (insn)) == SEQUENCE) 7367 { 7368 int count = 0; 7369 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--) 7370 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j) 7371 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j)) 7372 count++; 7373 return count; 7374 } 7375 else 7376 { 7377 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j) 7378 if (INSN_UID (insn) == VARRAY_INT (vec, j)) 7379 return 1; 7380 } 7381 return 0; 7382 } 7383 7384 int 7385 prologue_epilogue_contains (rtx insn) 7386 { 7387 if (contains (insn, prologue)) 7388 return 1; 7389 if (contains (insn, epilogue)) 7390 return 1; 7391 return 0; 7392 } 7393 7394 int 7395 sibcall_epilogue_contains (rtx insn) 7396 { 7397 if (sibcall_epilogue) 7398 return contains (insn, sibcall_epilogue); 7399 return 0; 7400 } 7401 7402 #ifdef HAVE_return 7403 /* Insert gen_return at the end of block BB. This also means updating 7404 block_for_insn appropriately. */ 7405 7406 static void 7407 emit_return_into_block (basic_block bb, rtx line_note) 7408 { 7409 emit_jump_insn_after (gen_return (), BB_END (bb)); 7410 if (line_note) 7411 emit_note_copy_after (line_note, PREV_INSN (BB_END (bb))); 7412 } 7413 #endif /* HAVE_return */ 7414 7415 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX) 7416 7417 /* These functions convert the epilogue into a variant that does not modify the 7418 stack pointer. This is used in cases where a function returns an object 7419 whose size is not known until it is computed. The called function leaves the 7420 object on the stack, leaves the stack depressed, and returns a pointer to 7421 the object. 7422 7423 What we need to do is track all modifications and references to the stack 7424 pointer, deleting the modifications and changing the references to point to 7425 the location the stack pointer would have pointed to had the modifications 7426 taken place. 7427 7428 These functions need to be portable so we need to make as few assumptions 7429 about the epilogue as we can. However, the epilogue basically contains 7430 three things: instructions to reset the stack pointer, instructions to 7431 reload registers, possibly including the frame pointer, and an 7432 instruction to return to the caller. 7433 7434 If we can't be sure of what a relevant epilogue insn is doing, we abort. 7435 We also make no attempt to validate the insns we make since if they are 7436 invalid, we probably can't do anything valid. The intent is that these 7437 routines get "smarter" as more and more machines start to use them and 7438 they try operating on different epilogues. 7439 7440 We use the following structure to track what the part of the epilogue that 7441 we've already processed has done. We keep two copies of the SP equivalence, 7442 one for use during the insn we are processing and one for use in the next 7443 insn. The difference is because one part of a PARALLEL may adjust SP 7444 and the other may use it. */ 7445 7446 struct epi_info 7447 { 7448 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */ 7449 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */ 7450 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */ 7451 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */ 7452 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG 7453 should be set to once we no longer need 7454 its value. */ 7455 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences 7456 for registers. */ 7457 }; 7458 7459 static void handle_epilogue_set (rtx, struct epi_info *); 7460 static void update_epilogue_consts (rtx, rtx, void *); 7461 static void emit_equiv_load (struct epi_info *); 7462 7463 /* Modify INSN, a list of one or more insns that is part of the epilogue, to 7464 no modifications to the stack pointer. Return the new list of insns. */ 7465 7466 static rtx 7467 keep_stack_depressed (rtx insns) 7468 { 7469 int j; 7470 struct epi_info info; 7471 rtx insn, next; 7472 7473 /* If the epilogue is just a single instruction, it must be OK as is. */ 7474 if (NEXT_INSN (insns) == NULL_RTX) 7475 return insns; 7476 7477 /* Otherwise, start a sequence, initialize the information we have, and 7478 process all the insns we were given. */ 7479 start_sequence (); 7480 7481 info.sp_equiv_reg = stack_pointer_rtx; 7482 info.sp_offset = 0; 7483 info.equiv_reg_src = 0; 7484 7485 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++) 7486 info.const_equiv[j] = 0; 7487 7488 insn = insns; 7489 next = NULL_RTX; 7490 while (insn != NULL_RTX) 7491 { 7492 next = NEXT_INSN (insn); 7493 7494 if (!INSN_P (insn)) 7495 { 7496 add_insn (insn); 7497 insn = next; 7498 continue; 7499 } 7500 7501 /* If this insn references the register that SP is equivalent to and 7502 we have a pending load to that register, we must force out the load 7503 first and then indicate we no longer know what SP's equivalent is. */ 7504 if (info.equiv_reg_src != 0 7505 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn))) 7506 { 7507 emit_equiv_load (&info); 7508 info.sp_equiv_reg = 0; 7509 } 7510 7511 info.new_sp_equiv_reg = info.sp_equiv_reg; 7512 info.new_sp_offset = info.sp_offset; 7513 7514 /* If this is a (RETURN) and the return address is on the stack, 7515 update the address and change to an indirect jump. */ 7516 if (GET_CODE (PATTERN (insn)) == RETURN 7517 || (GET_CODE (PATTERN (insn)) == PARALLEL 7518 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN)) 7519 { 7520 rtx retaddr = INCOMING_RETURN_ADDR_RTX; 7521 rtx base = 0; 7522 HOST_WIDE_INT offset = 0; 7523 rtx jump_insn, jump_set; 7524 7525 /* If the return address is in a register, we can emit the insn 7526 unchanged. Otherwise, it must be a MEM and we see what the 7527 base register and offset are. In any case, we have to emit any 7528 pending load to the equivalent reg of SP, if any. */ 7529 if (GET_CODE (retaddr) == REG) 7530 { 7531 emit_equiv_load (&info); 7532 add_insn (insn); 7533 insn = next; 7534 continue; 7535 } 7536 else if (GET_CODE (retaddr) == MEM 7537 && GET_CODE (XEXP (retaddr, 0)) == REG) 7538 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0; 7539 else if (GET_CODE (retaddr) == MEM 7540 && GET_CODE (XEXP (retaddr, 0)) == PLUS 7541 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG 7542 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT) 7543 { 7544 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0))); 7545 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1)); 7546 } 7547 else 7548 abort (); 7549 7550 /* If the base of the location containing the return pointer 7551 is SP, we must update it with the replacement address. Otherwise, 7552 just build the necessary MEM. */ 7553 retaddr = plus_constant (base, offset); 7554 if (base == stack_pointer_rtx) 7555 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx, 7556 plus_constant (info.sp_equiv_reg, 7557 info.sp_offset)); 7558 7559 retaddr = gen_rtx_MEM (Pmode, retaddr); 7560 7561 /* If there is a pending load to the equivalent register for SP 7562 and we reference that register, we must load our address into 7563 a scratch register and then do that load. */ 7564 if (info.equiv_reg_src 7565 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr)) 7566 { 7567 unsigned int regno; 7568 rtx reg; 7569 7570 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++) 7571 if (HARD_REGNO_MODE_OK (regno, Pmode) 7572 && !fixed_regs[regno] 7573 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno) 7574 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start, 7575 regno) 7576 && !refers_to_regno_p (regno, 7577 regno + HARD_REGNO_NREGS (regno, 7578 Pmode), 7579 info.equiv_reg_src, NULL) 7580 && info.const_equiv[regno] == 0) 7581 break; 7582 7583 if (regno == FIRST_PSEUDO_REGISTER) 7584 abort (); 7585 7586 reg = gen_rtx_REG (Pmode, regno); 7587 emit_move_insn (reg, retaddr); 7588 retaddr = reg; 7589 } 7590 7591 emit_equiv_load (&info); 7592 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr)); 7593 7594 /* Show the SET in the above insn is a RETURN. */ 7595 jump_set = single_set (jump_insn); 7596 if (jump_set == 0) 7597 abort (); 7598 else 7599 SET_IS_RETURN_P (jump_set) = 1; 7600 } 7601 7602 /* If SP is not mentioned in the pattern and its equivalent register, if 7603 any, is not modified, just emit it. Otherwise, if neither is set, 7604 replace the reference to SP and emit the insn. If none of those are 7605 true, handle each SET individually. */ 7606 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn)) 7607 && (info.sp_equiv_reg == stack_pointer_rtx 7608 || !reg_set_p (info.sp_equiv_reg, insn))) 7609 add_insn (insn); 7610 else if (! reg_set_p (stack_pointer_rtx, insn) 7611 && (info.sp_equiv_reg == stack_pointer_rtx 7612 || !reg_set_p (info.sp_equiv_reg, insn))) 7613 { 7614 if (! validate_replace_rtx (stack_pointer_rtx, 7615 plus_constant (info.sp_equiv_reg, 7616 info.sp_offset), 7617 insn)) 7618 abort (); 7619 7620 add_insn (insn); 7621 } 7622 else if (GET_CODE (PATTERN (insn)) == SET) 7623 handle_epilogue_set (PATTERN (insn), &info); 7624 else if (GET_CODE (PATTERN (insn)) == PARALLEL) 7625 { 7626 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++) 7627 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET) 7628 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info); 7629 } 7630 else 7631 add_insn (insn); 7632 7633 info.sp_equiv_reg = info.new_sp_equiv_reg; 7634 info.sp_offset = info.new_sp_offset; 7635 7636 /* Now update any constants this insn sets. */ 7637 note_stores (PATTERN (insn), update_epilogue_consts, &info); 7638 insn = next; 7639 } 7640 7641 insns = get_insns (); 7642 end_sequence (); 7643 return insns; 7644 } 7645 7646 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info 7647 structure that contains information about what we've seen so far. We 7648 process this SET by either updating that data or by emitting one or 7649 more insns. */ 7650 7651 static void 7652 handle_epilogue_set (rtx set, struct epi_info *p) 7653 { 7654 /* First handle the case where we are setting SP. Record what it is being 7655 set from. If unknown, abort. */ 7656 if (reg_set_p (stack_pointer_rtx, set)) 7657 { 7658 if (SET_DEST (set) != stack_pointer_rtx) 7659 abort (); 7660 7661 if (GET_CODE (SET_SRC (set)) == PLUS) 7662 { 7663 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0); 7664 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT) 7665 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1)); 7666 else if (GET_CODE (XEXP (SET_SRC (set), 1)) == REG 7667 && REGNO (XEXP (SET_SRC (set), 1)) < FIRST_PSEUDO_REGISTER 7668 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))] != 0) 7669 p->new_sp_offset 7670 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]); 7671 else 7672 abort (); 7673 } 7674 else 7675 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0; 7676 7677 /* If we are adjusting SP, we adjust from the old data. */ 7678 if (p->new_sp_equiv_reg == stack_pointer_rtx) 7679 { 7680 p->new_sp_equiv_reg = p->sp_equiv_reg; 7681 p->new_sp_offset += p->sp_offset; 7682 } 7683 7684 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG) 7685 abort (); 7686 7687 return; 7688 } 7689 7690 /* Next handle the case where we are setting SP's equivalent register. 7691 If we already have a value to set it to, abort. We could update, but 7692 there seems little point in handling that case. Note that we have 7693 to allow for the case where we are setting the register set in 7694 the previous part of a PARALLEL inside a single insn. But use the 7695 old offset for any updates within this insn. We must allow for the case 7696 where the register is being set in a different (usually wider) mode than 7697 Pmode). */ 7698 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set)) 7699 { 7700 if (p->equiv_reg_src != 0 7701 || GET_CODE (p->new_sp_equiv_reg) != REG 7702 || GET_CODE (SET_DEST (set)) != REG 7703 || GET_MODE_BITSIZE (GET_MODE (SET_DEST (set))) > BITS_PER_WORD 7704 || REGNO (p->new_sp_equiv_reg) != REGNO (SET_DEST (set))) 7705 abort (); 7706 else 7707 p->equiv_reg_src 7708 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx, 7709 plus_constant (p->sp_equiv_reg, 7710 p->sp_offset)); 7711 } 7712 7713 /* Otherwise, replace any references to SP in the insn to its new value 7714 and emit the insn. */ 7715 else 7716 { 7717 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx, 7718 plus_constant (p->sp_equiv_reg, 7719 p->sp_offset)); 7720 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx, 7721 plus_constant (p->sp_equiv_reg, 7722 p->sp_offset)); 7723 emit_insn (set); 7724 } 7725 } 7726 7727 /* Update the tracking information for registers set to constants. */ 7728 7729 static void 7730 update_epilogue_consts (rtx dest, rtx x, void *data) 7731 { 7732 struct epi_info *p = (struct epi_info *) data; 7733 7734 if (GET_CODE (dest) != REG || REGNO (dest) >= FIRST_PSEUDO_REGISTER) 7735 return; 7736 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x)) 7737 || GET_CODE (SET_SRC (x)) != CONST_INT) 7738 p->const_equiv[REGNO (dest)] = 0; 7739 else 7740 p->const_equiv[REGNO (dest)] = SET_SRC (x); 7741 } 7742 7743 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */ 7744 7745 static void 7746 emit_equiv_load (struct epi_info *p) 7747 { 7748 if (p->equiv_reg_src != 0) 7749 { 7750 rtx dest = p->sp_equiv_reg; 7751 7752 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest)) 7753 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src), 7754 REGNO (p->sp_equiv_reg)); 7755 7756 emit_move_insn (dest, p->equiv_reg_src); 7757 p->equiv_reg_src = 0; 7758 } 7759 } 7760 #endif 7761 7762 /* Generate the prologue and epilogue RTL if the machine supports it. Thread 7763 this into place with notes indicating where the prologue ends and where 7764 the epilogue begins. Update the basic block information when possible. */ 7765 7766 void 7767 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED) 7768 { 7769 int inserted = 0; 7770 edge e; 7771 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue) 7772 rtx seq; 7773 #endif 7774 #ifdef HAVE_prologue 7775 rtx prologue_end = NULL_RTX; 7776 #endif 7777 #if defined (HAVE_epilogue) || defined(HAVE_return) 7778 rtx epilogue_end = NULL_RTX; 7779 #endif 7780 7781 #ifdef HAVE_prologue 7782 if (HAVE_prologue) 7783 { 7784 start_sequence (); 7785 seq = gen_prologue (); 7786 emit_insn (seq); 7787 7788 /* Retain a map of the prologue insns. */ 7789 record_insns (seq, &prologue); 7790 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END); 7791 7792 seq = get_insns (); 7793 end_sequence (); 7794 set_insn_locators (seq, prologue_locator); 7795 7796 /* Can't deal with multiple successors of the entry block 7797 at the moment. Function should always have at least one 7798 entry point. */ 7799 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next) 7800 abort (); 7801 7802 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ); 7803 inserted = 1; 7804 } 7805 #endif 7806 7807 /* If the exit block has no non-fake predecessors, we don't need 7808 an epilogue. */ 7809 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next) 7810 if ((e->flags & EDGE_FAKE) == 0) 7811 break; 7812 if (e == NULL) 7813 goto epilogue_done; 7814 7815 #ifdef HAVE_return 7816 if (optimize && HAVE_return) 7817 { 7818 /* If we're allowed to generate a simple return instruction, 7819 then by definition we don't need a full epilogue. Examine 7820 the block that falls through to EXIT. If it does not 7821 contain any code, examine its predecessors and try to 7822 emit (conditional) return instructions. */ 7823 7824 basic_block last; 7825 edge e_next; 7826 rtx label; 7827 7828 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next) 7829 if (e->flags & EDGE_FALLTHRU) 7830 break; 7831 if (e == NULL) 7832 goto epilogue_done; 7833 last = e->src; 7834 7835 /* Verify that there are no active instructions in the last block. */ 7836 label = BB_END (last); 7837 while (label && GET_CODE (label) != CODE_LABEL) 7838 { 7839 if (active_insn_p (label)) 7840 break; 7841 label = PREV_INSN (label); 7842 } 7843 7844 if (BB_HEAD (last) == label && GET_CODE (label) == CODE_LABEL) 7845 { 7846 rtx epilogue_line_note = NULL_RTX; 7847 7848 /* Locate the line number associated with the closing brace, 7849 if we can find one. */ 7850 for (seq = get_last_insn (); 7851 seq && ! active_insn_p (seq); 7852 seq = PREV_INSN (seq)) 7853 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0) 7854 { 7855 epilogue_line_note = seq; 7856 break; 7857 } 7858 7859 for (e = last->pred; e; e = e_next) 7860 { 7861 basic_block bb = e->src; 7862 rtx jump; 7863 7864 e_next = e->pred_next; 7865 if (bb == ENTRY_BLOCK_PTR) 7866 continue; 7867 7868 jump = BB_END (bb); 7869 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label) 7870 continue; 7871 7872 /* If we have an unconditional jump, we can replace that 7873 with a simple return instruction. */ 7874 if (simplejump_p (jump)) 7875 { 7876 emit_return_into_block (bb, epilogue_line_note); 7877 delete_insn (jump); 7878 } 7879 7880 /* If we have a conditional jump, we can try to replace 7881 that with a conditional return instruction. */ 7882 else if (condjump_p (jump)) 7883 { 7884 if (! redirect_jump (jump, 0, 0)) 7885 continue; 7886 7887 /* If this block has only one successor, it both jumps 7888 and falls through to the fallthru block, so we can't 7889 delete the edge. */ 7890 if (bb->succ->succ_next == NULL) 7891 continue; 7892 } 7893 else 7894 continue; 7895 7896 /* Fix up the CFG for the successful change we just made. */ 7897 redirect_edge_succ (e, EXIT_BLOCK_PTR); 7898 } 7899 7900 /* Emit a return insn for the exit fallthru block. Whether 7901 this is still reachable will be determined later. */ 7902 7903 emit_barrier_after (BB_END (last)); 7904 emit_return_into_block (last, epilogue_line_note); 7905 epilogue_end = BB_END (last); 7906 last->succ->flags &= ~EDGE_FALLTHRU; 7907 goto epilogue_done; 7908 } 7909 } 7910 #endif 7911 #ifdef HAVE_epilogue 7912 if (HAVE_epilogue) 7913 { 7914 /* Find the edge that falls through to EXIT. Other edges may exist 7915 due to RETURN instructions, but those don't need epilogues. 7916 There really shouldn't be a mixture -- either all should have 7917 been converted or none, however... */ 7918 7919 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next) 7920 if (e->flags & EDGE_FALLTHRU) 7921 break; 7922 if (e == NULL) 7923 goto epilogue_done; 7924 7925 start_sequence (); 7926 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG); 7927 7928 seq = gen_epilogue (); 7929 7930 #ifdef INCOMING_RETURN_ADDR_RTX 7931 /* If this function returns with the stack depressed and we can support 7932 it, massage the epilogue to actually do that. */ 7933 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE 7934 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl))) 7935 seq = keep_stack_depressed (seq); 7936 #endif 7937 7938 emit_jump_insn (seq); 7939 7940 /* Retain a map of the epilogue insns. */ 7941 record_insns (seq, &epilogue); 7942 set_insn_locators (seq, epilogue_locator); 7943 7944 seq = get_insns (); 7945 end_sequence (); 7946 7947 insert_insn_on_edge (seq, e); 7948 inserted = 1; 7949 } 7950 #endif 7951 epilogue_done: 7952 7953 if (inserted) 7954 commit_edge_insertions (); 7955 7956 #ifdef HAVE_sibcall_epilogue 7957 /* Emit sibling epilogues before any sibling call sites. */ 7958 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next) 7959 { 7960 basic_block bb = e->src; 7961 rtx insn = BB_END (bb); 7962 rtx i; 7963 rtx newinsn; 7964 7965 if (GET_CODE (insn) != CALL_INSN 7966 || ! SIBLING_CALL_P (insn)) 7967 continue; 7968 7969 start_sequence (); 7970 emit_insn (gen_sibcall_epilogue ()); 7971 seq = get_insns (); 7972 end_sequence (); 7973 7974 /* Retain a map of the epilogue insns. Used in life analysis to 7975 avoid getting rid of sibcall epilogue insns. Do this before we 7976 actually emit the sequence. */ 7977 record_insns (seq, &sibcall_epilogue); 7978 set_insn_locators (seq, epilogue_locator); 7979 7980 i = PREV_INSN (insn); 7981 newinsn = emit_insn_before (seq, insn); 7982 } 7983 #endif 7984 7985 #ifdef HAVE_prologue 7986 /* This is probably all useless now that we use locators. */ 7987 if (prologue_end) 7988 { 7989 rtx insn, prev; 7990 7991 /* GDB handles `break f' by setting a breakpoint on the first 7992 line note after the prologue. Which means (1) that if 7993 there are line number notes before where we inserted the 7994 prologue we should move them, and (2) we should generate a 7995 note before the end of the first basic block, if there isn't 7996 one already there. 7997 7998 ??? This behavior is completely broken when dealing with 7999 multiple entry functions. We simply place the note always 8000 into first basic block and let alternate entry points 8001 to be missed. 8002 */ 8003 8004 for (insn = prologue_end; insn; insn = prev) 8005 { 8006 prev = PREV_INSN (insn); 8007 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0) 8008 { 8009 /* Note that we cannot reorder the first insn in the 8010 chain, since rest_of_compilation relies on that 8011 remaining constant. */ 8012 if (prev == NULL) 8013 break; 8014 reorder_insns (insn, insn, prologue_end); 8015 } 8016 } 8017 8018 /* Find the last line number note in the first block. */ 8019 for (insn = BB_END (ENTRY_BLOCK_PTR->next_bb); 8020 insn != prologue_end && insn; 8021 insn = PREV_INSN (insn)) 8022 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0) 8023 break; 8024 8025 /* If we didn't find one, make a copy of the first line number 8026 we run across. */ 8027 if (! insn) 8028 { 8029 for (insn = next_active_insn (prologue_end); 8030 insn; 8031 insn = PREV_INSN (insn)) 8032 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0) 8033 { 8034 emit_note_copy_after (insn, prologue_end); 8035 break; 8036 } 8037 } 8038 } 8039 #endif 8040 #ifdef HAVE_epilogue 8041 if (epilogue_end) 8042 { 8043 rtx insn, next; 8044 8045 /* Similarly, move any line notes that appear after the epilogue. 8046 There is no need, however, to be quite so anal about the existence 8047 of such a note. Also move the NOTE_INSN_FUNCTION_END and (possibly) 8048 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug 8049 info generation. */ 8050 for (insn = epilogue_end; insn; insn = next) 8051 { 8052 next = NEXT_INSN (insn); 8053 if (GET_CODE (insn) == NOTE 8054 && (NOTE_LINE_NUMBER (insn) > 0 8055 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG 8056 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_END)) 8057 reorder_insns (insn, insn, PREV_INSN (epilogue_end)); 8058 } 8059 } 8060 #endif 8061 } 8062 8063 /* Reposition the prologue-end and epilogue-begin notes after instruction 8064 scheduling and delayed branch scheduling. */ 8065 8066 void 8067 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED) 8068 { 8069 #if defined (HAVE_prologue) || defined (HAVE_epilogue) 8070 rtx insn, last, note; 8071 int len; 8072 8073 if ((len = VARRAY_SIZE (prologue)) > 0) 8074 { 8075 last = 0, note = 0; 8076 8077 /* Scan from the beginning until we reach the last prologue insn. 8078 We apparently can't depend on basic_block_{head,end} after 8079 reorg has run. */ 8080 for (insn = f; insn; insn = NEXT_INSN (insn)) 8081 { 8082 if (GET_CODE (insn) == NOTE) 8083 { 8084 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END) 8085 note = insn; 8086 } 8087 else if (contains (insn, prologue)) 8088 { 8089 last = insn; 8090 if (--len == 0) 8091 break; 8092 } 8093 } 8094 8095 if (last) 8096 { 8097 /* Find the prologue-end note if we haven't already, and 8098 move it to just after the last prologue insn. */ 8099 if (note == 0) 8100 { 8101 for (note = last; (note = NEXT_INSN (note));) 8102 if (GET_CODE (note) == NOTE 8103 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END) 8104 break; 8105 } 8106 8107 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */ 8108 if (GET_CODE (last) == CODE_LABEL) 8109 last = NEXT_INSN (last); 8110 reorder_insns (note, note, last); 8111 } 8112 } 8113 8114 if ((len = VARRAY_SIZE (epilogue)) > 0) 8115 { 8116 last = 0, note = 0; 8117 8118 /* Scan from the end until we reach the first epilogue insn. 8119 We apparently can't depend on basic_block_{head,end} after 8120 reorg has run. */ 8121 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn)) 8122 { 8123 if (GET_CODE (insn) == NOTE) 8124 { 8125 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG) 8126 note = insn; 8127 } 8128 else if (contains (insn, epilogue)) 8129 { 8130 last = insn; 8131 if (--len == 0) 8132 break; 8133 } 8134 } 8135 8136 if (last) 8137 { 8138 /* Find the epilogue-begin note if we haven't already, and 8139 move it to just before the first epilogue insn. */ 8140 if (note == 0) 8141 { 8142 for (note = insn; (note = PREV_INSN (note));) 8143 if (GET_CODE (note) == NOTE 8144 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG) 8145 break; 8146 } 8147 8148 if (PREV_INSN (last) != note) 8149 reorder_insns (note, note, PREV_INSN (last)); 8150 } 8151 } 8152 #endif /* HAVE_prologue or HAVE_epilogue */ 8153 } 8154 8155 /* Called once, at initialization, to initialize function.c. */ 8156 8157 void 8158 init_function_once (void) 8159 { 8160 VARRAY_INT_INIT (prologue, 0, "prologue"); 8161 VARRAY_INT_INIT (epilogue, 0, "epilogue"); 8162 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue"); 8163 } 8164 8165 /* Returns the name of the current function. */ 8166 const char * 8167 current_function_name (void) 8168 { 8169 return (*lang_hooks.decl_printable_name) (cfun->decl, 2); 8170 } 8171 8172 #include "gt-function.h" 8173