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.
5 This file is part of GCC.
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
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
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
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
43 #include "coretypes.h"
54 #include "hard-reg-set.h"
55 #include "insn-config.h"
58 #include "basic-block.h"
63 #include "integrate.h"
64 #include "langhooks.h"
67 #ifndef LOCAL_ALIGNMENT
68 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
71 #ifndef STACK_ALIGNMENT_NEEDED
72 #define STACK_ALIGNMENT_NEEDED 1
75 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
77 /* Some systems use __main in a way incompatible with its use in gcc, in these
78 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
79 give the same symbol without quotes for an alternative entry point. You
80 must define both, or neither. */
82 #define NAME__MAIN "__main"
85 /* Round a value to the lowest integer less than it that is a multiple of
86 the required alignment. Avoid using division in case the value is
87 negative. Assume the alignment is a power of two. */
88 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
90 /* Similar, but round to the next highest integer that meets the
92 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
94 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
95 during rtl generation. If they are different register numbers, this is
96 always true. It may also be true if
97 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
98 generation. See fix_lexical_addr for details. */
100 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
101 #define NEED_SEPARATE_AP
104 /* Nonzero if function being compiled doesn't contain any calls
105 (ignoring the prologue and epilogue). This is set prior to
106 local register allocation and is valid for the remaining
108 int current_function_is_leaf;
110 /* Nonzero if function being compiled doesn't contain any instructions
111 that can throw an exception. This is set prior to final. */
113 int current_function_nothrow;
115 /* Nonzero if function being compiled doesn't modify the stack pointer
116 (ignoring the prologue and epilogue). This is only valid after
117 life_analysis has run. */
118 int current_function_sp_is_unchanging;
120 /* Nonzero if the function being compiled is a leaf function which only
121 uses leaf registers. This is valid after reload (specifically after
122 sched2) and is useful only if the port defines LEAF_REGISTERS. */
123 int current_function_uses_only_leaf_regs;
125 /* Nonzero once virtual register instantiation has been done.
126 assign_stack_local uses frame_pointer_rtx when this is nonzero.
127 calls.c:emit_library_call_value_1 uses it to set up
128 post-instantiation libcalls. */
129 int virtuals_instantiated;
131 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
132 static GTY(()) int funcdef_no;
134 /* These variables hold pointers to functions to create and destroy
135 target specific, per-function data structures. */
136 struct machine_function * (*init_machine_status) (void);
138 /* The currently compiled function. */
139 struct function *cfun = 0;
141 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
142 static GTY(()) varray_type prologue;
143 static GTY(()) varray_type epilogue;
145 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
147 static GTY(()) varray_type sibcall_epilogue;
149 /* In order to evaluate some expressions, such as function calls returning
150 structures in memory, we need to temporarily allocate stack locations.
151 We record each allocated temporary in the following structure.
153 Associated with each temporary slot is a nesting level. When we pop up
154 one level, all temporaries associated with the previous level are freed.
155 Normally, all temporaries are freed after the execution of the statement
156 in which they were created. However, if we are inside a ({...}) grouping,
157 the result may be in a temporary and hence must be preserved. If the
158 result could be in a temporary, we preserve it if we can determine which
159 one it is in. If we cannot determine which temporary may contain the
160 result, all temporaries are preserved. A temporary is preserved by
161 pretending it was allocated at the previous nesting level.
163 Automatic variables are also assigned temporary slots, at the nesting
164 level where they are defined. They are marked a "kept" so that
165 free_temp_slots will not free them. */
167 struct temp_slot GTY(())
169 /* Points to next temporary slot. */
170 struct temp_slot *next;
171 /* The rtx to used to reference the slot. */
173 /* The rtx used to represent the address if not the address of the
174 slot above. May be an EXPR_LIST if multiple addresses exist. */
176 /* The alignment (in bits) of the slot. */
178 /* The size, in units, of the slot. */
180 /* The type of the object in the slot, or zero if it doesn't correspond
181 to a type. We use this to determine whether a slot can be reused.
182 It can be reused if objects of the type of the new slot will always
183 conflict with objects of the type of the old slot. */
185 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
187 /* Nonzero if this temporary is currently in use. */
189 /* Nonzero if this temporary has its address taken. */
191 /* Nesting level at which this slot is being used. */
193 /* Nonzero if this should survive a call to free_temp_slots. */
195 /* The offset of the slot from the frame_pointer, including extra space
196 for alignment. This info is for combine_temp_slots. */
197 HOST_WIDE_INT base_offset;
198 /* The size of the slot, including extra space for alignment. This
199 info is for combine_temp_slots. */
200 HOST_WIDE_INT full_size;
203 /* This structure is used to record MEMs or pseudos used to replace VAR, any
204 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
205 maintain this list in case two operands of an insn were required to match;
206 in that case we must ensure we use the same replacement. */
208 struct fixup_replacement GTY(())
212 struct fixup_replacement *next;
215 struct insns_for_mem_entry
219 /* These are the INSNs which reference the MEM. */
223 /* Forward declarations. */
225 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int,
227 static struct temp_slot *find_temp_slot_from_address (rtx);
228 static void put_reg_into_stack (struct function *, rtx, tree, enum machine_mode,
229 unsigned int, bool, bool, bool, htab_t);
230 static void schedule_fixup_var_refs (struct function *, rtx, tree, enum machine_mode,
232 static void fixup_var_refs (rtx, enum machine_mode, int, rtx, htab_t);
233 static struct fixup_replacement
234 *find_fixup_replacement (struct fixup_replacement **, rtx);
235 static void fixup_var_refs_insns (rtx, rtx, enum machine_mode, int, int, rtx);
236 static void fixup_var_refs_insns_with_hash (htab_t, rtx, enum machine_mode, int, rtx);
237 static void fixup_var_refs_insn (rtx, rtx, enum machine_mode, int, int, rtx);
238 static void fixup_var_refs_1 (rtx, enum machine_mode, rtx *, rtx,
239 struct fixup_replacement **, rtx);
240 static rtx fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
241 static rtx walk_fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
242 static rtx fixup_stack_1 (rtx, rtx);
243 static void optimize_bit_field (rtx, rtx, rtx *);
244 static void instantiate_decls (tree, int);
245 static void instantiate_decls_1 (tree, int);
246 static void instantiate_decl (rtx, HOST_WIDE_INT, int);
247 static rtx instantiate_new_reg (rtx, HOST_WIDE_INT *);
248 static int instantiate_virtual_regs_1 (rtx *, rtx, int);
249 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
250 static void pad_below (struct args_size *, enum machine_mode, tree);
251 static tree *identify_blocks_1 (rtx, tree *, tree *, tree *);
252 static void reorder_blocks_1 (rtx, tree, varray_type *);
253 static void reorder_fix_fragments (tree);
254 static int all_blocks (tree, tree *);
255 static tree *get_block_vector (tree, int *);
256 extern tree debug_find_var_in_block_tree (tree, tree);
257 /* We always define `record_insns' even if it's not used so that we
258 can always export `prologue_epilogue_contains'. */
259 static void record_insns (rtx, varray_type *) ATTRIBUTE_UNUSED;
260 static int contains (rtx, varray_type);
262 static void emit_return_into_block (basic_block, rtx);
264 static void put_addressof_into_stack (rtx, htab_t);
265 static bool purge_addressof_1 (rtx *, rtx, int, int, int, htab_t);
266 static void purge_single_hard_subreg_set (rtx);
267 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
268 static rtx keep_stack_depressed (rtx);
270 static int is_addressof (rtx *, void *);
271 static hashval_t insns_for_mem_hash (const void *);
272 static int insns_for_mem_comp (const void *, const void *);
273 static int insns_for_mem_walk (rtx *, void *);
274 static void compute_insns_for_mem (rtx, rtx, htab_t);
275 static void prepare_function_start (tree);
276 static void do_clobber_return_reg (rtx, void *);
277 static void do_use_return_reg (rtx, void *);
278 static void instantiate_virtual_regs_lossage (rtx);
279 static tree split_complex_args (tree);
280 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
282 /* Pointer to chain of `struct function' for containing functions. */
283 struct function *outer_function_chain;
285 /* List of insns that were postponed by purge_addressof_1. */
286 static rtx postponed_insns;
288 /* Given a function decl for a containing function,
289 return the `struct function' for it. */
292 find_function_data (tree decl)
296 for (p = outer_function_chain; p; p = p->outer)
303 /* Save the current context for compilation of a nested function.
304 This is called from language-specific code. The caller should use
305 the enter_nested langhook to save any language-specific state,
306 since this function knows only about language-independent
310 push_function_context_to (tree context)
316 if (context == current_function_decl)
317 cfun->contains_functions = 1;
320 struct function *containing = find_function_data (context);
321 containing->contains_functions = 1;
326 init_dummy_function_start ();
329 p->outer = outer_function_chain;
330 outer_function_chain = p;
331 p->fixup_var_refs_queue = 0;
333 lang_hooks.function.enter_nested (p);
339 push_function_context (void)
341 push_function_context_to (current_function_decl);
344 /* Restore the last saved context, at the end of a nested function.
345 This function is called from language-specific code. */
348 pop_function_context_from (tree context ATTRIBUTE_UNUSED)
350 struct function *p = outer_function_chain;
351 struct var_refs_queue *queue;
354 outer_function_chain = p->outer;
356 current_function_decl = p->decl;
359 restore_emit_status (p);
361 lang_hooks.function.leave_nested (p);
363 /* Finish doing put_var_into_stack for any of our variables which became
364 addressable during the nested function. If only one entry has to be
365 fixed up, just do that one. Otherwise, first make a list of MEMs that
366 are not to be unshared. */
367 if (p->fixup_var_refs_queue == 0)
369 else if (p->fixup_var_refs_queue->next == 0)
370 fixup_var_refs (p->fixup_var_refs_queue->modified,
371 p->fixup_var_refs_queue->promoted_mode,
372 p->fixup_var_refs_queue->unsignedp,
373 p->fixup_var_refs_queue->modified, 0);
378 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
379 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
381 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
382 fixup_var_refs (queue->modified, queue->promoted_mode,
383 queue->unsignedp, list, 0);
387 p->fixup_var_refs_queue = 0;
389 /* Reset variables that have known state during rtx generation. */
390 rtx_equal_function_value_matters = 1;
391 virtuals_instantiated = 0;
392 generating_concat_p = 1;
396 pop_function_context (void)
398 pop_function_context_from (current_function_decl);
401 /* Clear out all parts of the state in F that can safely be discarded
402 after the function has been parsed, but not compiled, to let
403 garbage collection reclaim the memory. */
406 free_after_parsing (struct function *f)
408 /* f->expr->forced_labels is used by code generation. */
409 /* f->emit->regno_reg_rtx is used by code generation. */
410 /* f->varasm is used by code generation. */
411 /* f->eh->eh_return_stub_label is used by code generation. */
413 lang_hooks.function.final (f);
417 /* Clear out all parts of the state in F that can safely be discarded
418 after the function has been compiled, to let garbage collection
419 reclaim the memory. */
422 free_after_compilation (struct function *f)
430 f->x_temp_slots = NULL;
431 f->arg_offset_rtx = NULL;
432 f->return_rtx = NULL;
433 f->internal_arg_pointer = NULL;
434 f->x_nonlocal_goto_handler_labels = NULL;
435 f->x_cleanup_label = NULL;
436 f->x_return_label = NULL;
437 f->x_naked_return_label = NULL;
438 f->computed_goto_common_label = NULL;
439 f->computed_goto_common_reg = NULL;
440 f->x_save_expr_regs = NULL;
441 f->x_stack_slot_list = NULL;
442 f->x_rtl_expr_chain = NULL;
443 f->x_tail_recursion_label = NULL;
444 f->x_tail_recursion_reentry = NULL;
445 f->x_arg_pointer_save_area = NULL;
446 f->x_parm_birth_insn = NULL;
447 f->x_last_parm_insn = NULL;
448 f->x_parm_reg_stack_loc = NULL;
449 f->fixup_var_refs_queue = NULL;
450 f->original_arg_vector = NULL;
451 f->original_decl_initial = NULL;
452 f->inl_last_parm_insn = NULL;
453 f->epilogue_delay_list = NULL;
456 /* Allocate fixed slots in the stack frame of the current function. */
458 /* Return size needed for stack frame based on slots so far allocated in
460 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
461 the caller may have to do that. */
464 get_func_frame_size (struct function *f)
466 #ifdef FRAME_GROWS_DOWNWARD
467 return -f->x_frame_offset;
469 return f->x_frame_offset;
473 /* Return size needed for stack frame based on slots so far allocated.
474 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
475 the caller may have to do that. */
477 get_frame_size (void)
479 return get_func_frame_size (cfun);
482 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
483 with machine mode MODE.
485 ALIGN controls the amount of alignment for the address of the slot:
486 0 means according to MODE,
487 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
488 -2 means use BITS_PER_UNIT,
489 positive specifies alignment boundary in bits.
491 We do not round to stack_boundary here.
493 FUNCTION specifies the function to allocate in. */
496 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
497 struct function *function)
500 int bigend_correction = 0;
502 int frame_off, frame_alignment, frame_phase;
509 alignment = BIGGEST_ALIGNMENT;
511 alignment = GET_MODE_ALIGNMENT (mode);
513 /* Allow the target to (possibly) increase the alignment of this
515 type = lang_hooks.types.type_for_mode (mode, 0);
517 alignment = LOCAL_ALIGNMENT (type, alignment);
519 alignment /= BITS_PER_UNIT;
521 else if (align == -1)
523 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
524 size = CEIL_ROUND (size, alignment);
526 else if (align == -2)
527 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
529 alignment = align / BITS_PER_UNIT;
531 #ifdef FRAME_GROWS_DOWNWARD
532 function->x_frame_offset -= size;
535 /* Ignore alignment we can't do with expected alignment of the boundary. */
536 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
537 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
539 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
540 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
542 /* Calculate how many bytes the start of local variables is off from
544 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
545 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
546 frame_phase = frame_off ? frame_alignment - frame_off : 0;
548 /* Round the frame offset to the specified alignment. The default is
549 to always honor requests to align the stack but a port may choose to
550 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
551 if (STACK_ALIGNMENT_NEEDED
555 /* We must be careful here, since FRAME_OFFSET might be negative and
556 division with a negative dividend isn't as well defined as we might
557 like. So we instead assume that ALIGNMENT is a power of two and
558 use logical operations which are unambiguous. */
559 #ifdef FRAME_GROWS_DOWNWARD
560 function->x_frame_offset
561 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
564 function->x_frame_offset
565 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
570 /* On a big-endian machine, if we are allocating more space than we will use,
571 use the least significant bytes of those that are allocated. */
572 if (BYTES_BIG_ENDIAN && mode != BLKmode)
573 bigend_correction = size - GET_MODE_SIZE (mode);
575 /* If we have already instantiated virtual registers, return the actual
576 address relative to the frame pointer. */
577 if (function == cfun && virtuals_instantiated)
578 addr = plus_constant (frame_pointer_rtx,
580 (frame_offset + bigend_correction
581 + STARTING_FRAME_OFFSET, Pmode));
583 addr = plus_constant (virtual_stack_vars_rtx,
585 (function->x_frame_offset + bigend_correction,
588 #ifndef FRAME_GROWS_DOWNWARD
589 function->x_frame_offset += size;
592 x = gen_rtx_MEM (mode, addr);
594 function->x_stack_slot_list
595 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
600 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
604 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
606 return assign_stack_local_1 (mode, size, align, cfun);
609 /* Allocate a temporary stack slot and record it for possible later
612 MODE is the machine mode to be given to the returned rtx.
614 SIZE is the size in units of the space required. We do no rounding here
615 since assign_stack_local will do any required rounding.
617 KEEP is 1 if this slot is to be retained after a call to
618 free_temp_slots. Automatic variables for a block are allocated
619 with this flag. KEEP is 2 if we allocate a longer term temporary,
620 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
621 if we are to allocate something at an inner level to be treated as
622 a variable in the block (e.g., a SAVE_EXPR).
624 TYPE is the type that will be used for the stack slot. */
627 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, int keep,
631 struct temp_slot *p, *best_p = 0;
634 /* If SIZE is -1 it means that somebody tried to allocate a temporary
635 of a variable size. */
640 align = BIGGEST_ALIGNMENT;
642 align = GET_MODE_ALIGNMENT (mode);
645 type = lang_hooks.types.type_for_mode (mode, 0);
648 align = LOCAL_ALIGNMENT (type, align);
650 /* Try to find an available, already-allocated temporary of the proper
651 mode which meets the size and alignment requirements. Choose the
652 smallest one with the closest alignment. */
653 for (p = temp_slots; p; p = p->next)
654 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
656 && objects_must_conflict_p (p->type, type)
657 && (best_p == 0 || best_p->size > p->size
658 || (best_p->size == p->size && best_p->align > p->align)))
660 if (p->align == align && p->size == size)
668 /* Make our best, if any, the one to use. */
671 /* If there are enough aligned bytes left over, make them into a new
672 temp_slot so that the extra bytes don't get wasted. Do this only
673 for BLKmode slots, so that we can be sure of the alignment. */
674 if (GET_MODE (best_p->slot) == BLKmode)
676 int alignment = best_p->align / BITS_PER_UNIT;
677 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
679 if (best_p->size - rounded_size >= alignment)
681 p = ggc_alloc (sizeof (struct temp_slot));
682 p->in_use = p->addr_taken = 0;
683 p->size = best_p->size - rounded_size;
684 p->base_offset = best_p->base_offset + rounded_size;
685 p->full_size = best_p->full_size - rounded_size;
686 p->slot = gen_rtx_MEM (BLKmode,
687 plus_constant (XEXP (best_p->slot, 0),
689 p->align = best_p->align;
692 p->type = best_p->type;
693 p->next = temp_slots;
696 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
699 best_p->size = rounded_size;
700 best_p->full_size = rounded_size;
707 /* If we still didn't find one, make a new temporary. */
710 HOST_WIDE_INT frame_offset_old = frame_offset;
712 p = ggc_alloc (sizeof (struct temp_slot));
714 /* We are passing an explicit alignment request to assign_stack_local.
715 One side effect of that is assign_stack_local will not round SIZE
716 to ensure the frame offset remains suitably aligned.
718 So for requests which depended on the rounding of SIZE, we go ahead
719 and round it now. We also make sure ALIGNMENT is at least
720 BIGGEST_ALIGNMENT. */
721 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
723 p->slot = assign_stack_local (mode,
725 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
731 /* The following slot size computation is necessary because we don't
732 know the actual size of the temporary slot until assign_stack_local
733 has performed all the frame alignment and size rounding for the
734 requested temporary. Note that extra space added for alignment
735 can be either above or below this stack slot depending on which
736 way the frame grows. We include the extra space if and only if it
737 is above this slot. */
738 #ifdef FRAME_GROWS_DOWNWARD
739 p->size = frame_offset_old - frame_offset;
744 /* Now define the fields used by combine_temp_slots. */
745 #ifdef FRAME_GROWS_DOWNWARD
746 p->base_offset = frame_offset;
747 p->full_size = frame_offset_old - frame_offset;
749 p->base_offset = frame_offset_old;
750 p->full_size = frame_offset - frame_offset_old;
753 p->next = temp_slots;
759 p->rtl_expr = seq_rtl_expr;
764 p->level = target_temp_slot_level;
769 p->level = var_temp_slot_level;
774 p->level = temp_slot_level;
779 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
780 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
781 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
783 /* If we know the alias set for the memory that will be used, use
784 it. If there's no TYPE, then we don't know anything about the
785 alias set for the memory. */
786 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
787 set_mem_align (slot, align);
789 /* If a type is specified, set the relevant flags. */
792 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
793 && TYPE_READONLY (type));
794 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
795 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
801 /* Allocate a temporary stack slot and record it for possible later
802 reuse. First three arguments are same as in preceding function. */
805 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
807 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
810 /* Assign a temporary.
811 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
812 and so that should be used in error messages. In either case, we
813 allocate of the given type.
814 KEEP is as for assign_stack_temp.
815 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
816 it is 0 if a register is OK.
817 DONT_PROMOTE is 1 if we should not promote values in register
821 assign_temp (tree type_or_decl, int keep, int memory_required,
822 int dont_promote ATTRIBUTE_UNUSED)
825 enum machine_mode mode;
830 if (DECL_P (type_or_decl))
831 decl = type_or_decl, type = TREE_TYPE (decl);
833 decl = NULL, type = type_or_decl;
835 mode = TYPE_MODE (type);
837 unsignedp = TYPE_UNSIGNED (type);
840 if (mode == BLKmode || memory_required)
842 HOST_WIDE_INT size = int_size_in_bytes (type);
845 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
846 problems with allocating the stack space. */
850 /* Unfortunately, we don't yet know how to allocate variable-sized
851 temporaries. However, sometimes we have a fixed upper limit on
852 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
853 instead. This is the case for Chill variable-sized strings. */
854 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
855 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
856 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
857 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
859 /* The size of the temporary may be too large to fit into an integer. */
860 /* ??? Not sure this should happen except for user silliness, so limit
861 this to things that aren't compiler-generated temporaries. The
862 rest of the time we'll abort in assign_stack_temp_for_type. */
863 if (decl && size == -1
864 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
866 error ("%Jsize of variable '%D' is too large", decl, decl);
870 tmp = assign_stack_temp_for_type (mode, size, keep, type);
876 mode = promote_mode (type, mode, &unsignedp, 0);
879 return gen_reg_rtx (mode);
882 /* Combine temporary stack slots which are adjacent on the stack.
884 This allows for better use of already allocated stack space. This is only
885 done for BLKmode slots because we can be sure that we won't have alignment
886 problems in this case. */
889 combine_temp_slots (void)
891 struct temp_slot *p, *q;
892 struct temp_slot *prev_p, *prev_q;
895 /* We can't combine slots, because the information about which slot
896 is in which alias set will be lost. */
897 if (flag_strict_aliasing)
900 /* If there are a lot of temp slots, don't do anything unless
901 high levels of optimization. */
902 if (! flag_expensive_optimizations)
903 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
904 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
907 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
911 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
912 for (q = p->next, prev_q = p; q; q = prev_q->next)
915 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
917 if (p->base_offset + p->full_size == q->base_offset)
919 /* Q comes after P; combine Q into P. */
921 p->full_size += q->full_size;
924 else if (q->base_offset + q->full_size == p->base_offset)
926 /* P comes after Q; combine P into Q. */
928 q->full_size += p->full_size;
933 /* Either delete Q or advance past it. */
935 prev_q->next = q->next;
939 /* Either delete P or advance past it. */
943 prev_p->next = p->next;
945 temp_slots = p->next;
952 /* Find the temp slot corresponding to the object at address X. */
954 static struct temp_slot *
955 find_temp_slot_from_address (rtx x)
960 for (p = temp_slots; p; p = p->next)
965 else if (XEXP (p->slot, 0) == x
967 || (GET_CODE (x) == PLUS
968 && XEXP (x, 0) == virtual_stack_vars_rtx
969 && GET_CODE (XEXP (x, 1)) == CONST_INT
970 && INTVAL (XEXP (x, 1)) >= p->base_offset
971 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
974 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
975 for (next = p->address; next; next = XEXP (next, 1))
976 if (XEXP (next, 0) == x)
980 /* If we have a sum involving a register, see if it points to a temp
982 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
983 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
985 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
986 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
992 /* Indicate that NEW is an alternate way of referring to the temp slot
993 that previously was known by OLD. */
996 update_temp_slot_address (rtx old, rtx new)
1000 if (rtx_equal_p (old, new))
1003 p = find_temp_slot_from_address (old);
1005 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1006 is a register, see if one operand of the PLUS is a temporary
1007 location. If so, NEW points into it. Otherwise, if both OLD and
1008 NEW are a PLUS and if there is a register in common between them.
1009 If so, try a recursive call on those values. */
1012 if (GET_CODE (old) != PLUS)
1015 if (GET_CODE (new) == REG)
1017 update_temp_slot_address (XEXP (old, 0), new);
1018 update_temp_slot_address (XEXP (old, 1), new);
1021 else if (GET_CODE (new) != PLUS)
1024 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1025 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1026 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1027 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1028 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1029 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1030 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1031 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1036 /* Otherwise add an alias for the temp's address. */
1037 else if (p->address == 0)
1041 if (GET_CODE (p->address) != EXPR_LIST)
1042 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1044 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1048 /* If X could be a reference to a temporary slot, mark the fact that its
1049 address was taken. */
1052 mark_temp_addr_taken (rtx x)
1054 struct temp_slot *p;
1059 /* If X is not in memory or is at a constant address, it cannot be in
1060 a temporary slot. */
1061 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1064 p = find_temp_slot_from_address (XEXP (x, 0));
1069 /* If X could be a reference to a temporary slot, mark that slot as
1070 belonging to the to one level higher than the current level. If X
1071 matched one of our slots, just mark that one. Otherwise, we can't
1072 easily predict which it is, so upgrade all of them. Kept slots
1073 need not be touched.
1075 This is called when an ({...}) construct occurs and a statement
1076 returns a value in memory. */
1079 preserve_temp_slots (rtx x)
1081 struct temp_slot *p = 0;
1083 /* If there is no result, we still might have some objects whose address
1084 were taken, so we need to make sure they stay around. */
1087 for (p = temp_slots; p; p = p->next)
1088 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1094 /* If X is a register that is being used as a pointer, see if we have
1095 a temporary slot we know it points to. To be consistent with
1096 the code below, we really should preserve all non-kept slots
1097 if we can't find a match, but that seems to be much too costly. */
1098 if (GET_CODE (x) == REG && REG_POINTER (x))
1099 p = find_temp_slot_from_address (x);
1101 /* If X is not in memory or is at a constant address, it cannot be in
1102 a temporary slot, but it can contain something whose address was
1104 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1106 for (p = temp_slots; p; p = p->next)
1107 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1113 /* First see if we can find a match. */
1115 p = find_temp_slot_from_address (XEXP (x, 0));
1119 /* Move everything at our level whose address was taken to our new
1120 level in case we used its address. */
1121 struct temp_slot *q;
1123 if (p->level == temp_slot_level)
1125 for (q = temp_slots; q; q = q->next)
1126 if (q != p && q->addr_taken && q->level == p->level)
1135 /* Otherwise, preserve all non-kept slots at this level. */
1136 for (p = temp_slots; p; p = p->next)
1137 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1141 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1142 with that RTL_EXPR, promote it into a temporary slot at the present
1143 level so it will not be freed when we free slots made in the
1147 preserve_rtl_expr_result (rtx x)
1149 struct temp_slot *p;
1151 /* If X is not in memory or is at a constant address, it cannot be in
1152 a temporary slot. */
1153 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1156 /* If we can find a match, move it to our level unless it is already at
1158 p = find_temp_slot_from_address (XEXP (x, 0));
1161 p->level = MIN (p->level, temp_slot_level);
1168 /* Free all temporaries used so far. This is normally called at the end
1169 of generating code for a statement. Don't free any temporaries
1170 currently in use for an RTL_EXPR that hasn't yet been emitted.
1171 We could eventually do better than this since it can be reused while
1172 generating the same RTL_EXPR, but this is complex and probably not
1176 free_temp_slots (void)
1178 struct temp_slot *p;
1180 for (p = temp_slots; p; p = p->next)
1181 if (p->in_use && p->level == temp_slot_level && ! p->keep
1182 && p->rtl_expr == 0)
1185 combine_temp_slots ();
1188 /* Free all temporary slots used in T, an RTL_EXPR node. */
1191 free_temps_for_rtl_expr (tree t)
1193 struct temp_slot *p;
1195 for (p = temp_slots; p; p = p->next)
1196 if (p->rtl_expr == t)
1198 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1199 needs to be preserved. This can happen if a temporary in
1200 the RTL_EXPR was addressed; preserve_temp_slots will move
1201 the temporary into a higher level. */
1202 if (temp_slot_level <= p->level)
1205 p->rtl_expr = NULL_TREE;
1208 combine_temp_slots ();
1211 /* Mark all temporaries ever allocated in this function as not suitable
1212 for reuse until the current level is exited. */
1215 mark_all_temps_used (void)
1217 struct temp_slot *p;
1219 for (p = temp_slots; p; p = p->next)
1221 p->in_use = p->keep = 1;
1222 p->level = MIN (p->level, temp_slot_level);
1226 /* Push deeper into the nesting level for stack temporaries. */
1229 push_temp_slots (void)
1234 /* Pop a temporary nesting level. All slots in use in the current level
1238 pop_temp_slots (void)
1240 struct temp_slot *p;
1242 for (p = temp_slots; p; p = p->next)
1243 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1246 combine_temp_slots ();
1251 /* Initialize temporary slots. */
1254 init_temp_slots (void)
1256 /* We have not allocated any temporaries yet. */
1258 temp_slot_level = 0;
1259 var_temp_slot_level = 0;
1260 target_temp_slot_level = 0;
1263 /* Retroactively move an auto variable from a register to a stack
1264 slot. This is done when an address-reference to the variable is
1265 seen. If RESCAN is true, all previously emitted instructions are
1266 examined and modified to handle the fact that DECL is now
1270 put_var_into_stack (tree decl, int rescan)
1273 enum machine_mode promoted_mode, decl_mode;
1274 struct function *function = 0;
1276 bool can_use_addressof_p;
1277 bool volatile_p = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1278 bool used_p = (TREE_USED (decl)
1279 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1281 context = decl_function_context (decl);
1283 /* Get the current rtl used for this object and its original mode. */
1284 orig_reg = reg = (TREE_CODE (decl) == SAVE_EXPR
1285 ? SAVE_EXPR_RTL (decl)
1286 : DECL_RTL_IF_SET (decl));
1288 /* No need to do anything if decl has no rtx yet
1289 since in that case caller is setting TREE_ADDRESSABLE
1290 and a stack slot will be assigned when the rtl is made. */
1294 /* Get the declared mode for this object. */
1295 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1296 : DECL_MODE (decl));
1297 /* Get the mode it's actually stored in. */
1298 promoted_mode = GET_MODE (reg);
1300 /* If this variable comes from an outer function, find that
1301 function's saved context. Don't use find_function_data here,
1302 because it might not be in any active function.
1303 FIXME: Is that really supposed to happen?
1304 It does in ObjC at least. */
1305 if (context != current_function_decl)
1306 for (function = outer_function_chain; function; function = function->outer)
1307 if (function->decl == context)
1310 /* If this is a variable-sized object or a structure passed by invisible
1311 reference, with a pseudo to address it, put that pseudo into the stack
1312 if the var is non-local. */
1313 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1314 && GET_CODE (reg) == MEM
1315 && GET_CODE (XEXP (reg, 0)) == REG
1316 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1318 orig_reg = reg = XEXP (reg, 0);
1319 decl_mode = promoted_mode = GET_MODE (reg);
1322 /* If this variable lives in the current function and we don't need to put it
1323 in the stack for the sake of setjmp or the non-locality, try to keep it in
1324 a register until we know we actually need the address. */
1327 && ! (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl))
1329 /* FIXME make it work for promoted modes too */
1330 && decl_mode == promoted_mode
1331 #ifdef NON_SAVING_SETJMP
1332 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1336 /* If we can't use ADDRESSOF, make sure we see through one we already
1338 if (! can_use_addressof_p
1339 && GET_CODE (reg) == MEM
1340 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1341 reg = XEXP (XEXP (reg, 0), 0);
1343 /* Now we should have a value that resides in one or more pseudo regs. */
1345 if (GET_CODE (reg) == REG)
1347 if (can_use_addressof_p)
1348 gen_mem_addressof (reg, decl, rescan);
1350 put_reg_into_stack (function, reg, TREE_TYPE (decl), decl_mode,
1351 0, volatile_p, used_p, false, 0);
1353 /* If this was previously a MEM but we've removed the ADDRESSOF,
1354 set this address into that MEM so we always use the same
1355 rtx for this variable. */
1356 if (orig_reg != reg && GET_CODE (orig_reg) == MEM)
1357 XEXP (orig_reg, 0) = XEXP (reg, 0);
1359 else if (GET_CODE (reg) == CONCAT)
1361 /* A CONCAT contains two pseudos; put them both in the stack.
1362 We do it so they end up consecutive.
1363 We fixup references to the parts only after we fixup references
1364 to the whole CONCAT, lest we do double fixups for the latter
1366 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1367 tree part_type = lang_hooks.types.type_for_mode (part_mode, 0);
1368 rtx lopart = XEXP (reg, 0);
1369 rtx hipart = XEXP (reg, 1);
1370 #ifdef FRAME_GROWS_DOWNWARD
1371 /* Since part 0 should have a lower address, do it second. */
1372 put_reg_into_stack (function, hipart, part_type, part_mode,
1373 0, volatile_p, false, false, 0);
1374 put_reg_into_stack (function, lopart, part_type, part_mode,
1375 0, volatile_p, false, true, 0);
1377 put_reg_into_stack (function, lopart, part_type, part_mode,
1378 0, volatile_p, false, false, 0);
1379 put_reg_into_stack (function, hipart, part_type, part_mode,
1380 0, volatile_p, false, true, 0);
1383 /* Change the CONCAT into a combined MEM for both parts. */
1384 PUT_CODE (reg, MEM);
1385 MEM_ATTRS (reg) = 0;
1387 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1388 already computed alias sets. Here we want to re-generate. */
1390 SET_DECL_RTL (decl, NULL);
1391 set_mem_attributes (reg, decl, 1);
1393 SET_DECL_RTL (decl, reg);
1395 /* The two parts are in memory order already.
1396 Use the lower parts address as ours. */
1397 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1398 /* Prevent sharing of rtl that might lose. */
1399 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1400 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1401 if (used_p && rescan)
1403 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1405 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1406 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1413 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1414 into the stack frame of FUNCTION (0 means the current function).
1415 TYPE is the user-level data type of the value hold in the register.
1416 DECL_MODE is the machine mode of the user-level data type.
1417 ORIGINAL_REGNO must be set if the real regno is not visible in REG.
1418 VOLATILE_P is true if this is for a "volatile" decl.
1419 USED_P is true if this reg might have already been used in an insn.
1420 CONSECUTIVE_P is true if the stack slot assigned to reg must be
1421 consecutive with the previous stack slot. */
1424 put_reg_into_stack (struct function *function, rtx reg, tree type,
1425 enum machine_mode decl_mode, unsigned int original_regno,
1426 bool volatile_p, bool used_p, bool consecutive_p,
1429 struct function *func = function ? function : cfun;
1430 enum machine_mode mode = GET_MODE (reg);
1431 unsigned int regno = original_regno;
1435 regno = REGNO (reg);
1437 if (regno < func->x_max_parm_reg)
1439 if (!func->x_parm_reg_stack_loc)
1441 new = func->x_parm_reg_stack_loc[regno];
1445 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode),
1446 consecutive_p ? -2 : 0, func);
1448 PUT_CODE (reg, MEM);
1449 PUT_MODE (reg, decl_mode);
1450 XEXP (reg, 0) = XEXP (new, 0);
1451 MEM_ATTRS (reg) = 0;
1452 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1453 MEM_VOLATILE_P (reg) = volatile_p;
1455 /* If this is a memory ref that contains aggregate components,
1456 mark it as such for cse and loop optimize. If we are reusing a
1457 previously generated stack slot, then we need to copy the bit in
1458 case it was set for other reasons. For instance, it is set for
1459 __builtin_va_alist. */
1462 MEM_SET_IN_STRUCT_P (reg,
1463 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1464 set_mem_alias_set (reg, get_alias_set (type));
1468 schedule_fixup_var_refs (function, reg, type, mode, ht);
1471 /* Make sure that all refs to the variable, previously made
1472 when it was a register, are fixed up to be valid again.
1473 See function above for meaning of arguments. */
1476 schedule_fixup_var_refs (struct function *function, rtx reg, tree type,
1477 enum machine_mode promoted_mode, htab_t ht)
1479 int unsigned_p = type ? TYPE_UNSIGNED (type) : 0;
1483 struct var_refs_queue *temp;
1485 temp = ggc_alloc (sizeof (struct var_refs_queue));
1486 temp->modified = reg;
1487 temp->promoted_mode = promoted_mode;
1488 temp->unsignedp = unsigned_p;
1489 temp->next = function->fixup_var_refs_queue;
1490 function->fixup_var_refs_queue = temp;
1493 /* Variable is local; fix it up now. */
1494 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1498 fixup_var_refs (rtx var, enum machine_mode promoted_mode, int unsignedp,
1499 rtx may_share, htab_t ht)
1502 rtx first_insn = get_insns ();
1503 struct sequence_stack *stack = seq_stack;
1504 tree rtl_exps = rtl_expr_chain;
1505 int save_volatile_ok = volatile_ok;
1507 /* If there's a hash table, it must record all uses of VAR. */
1512 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1517 /* Volatile is valid in MEMs because all we're doing in changing the
1520 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1521 stack == 0, may_share);
1523 /* Scan all pending sequences too. */
1524 for (; stack; stack = stack->next)
1526 push_to_full_sequence (stack->first, stack->last);
1527 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1528 stack->next != 0, may_share);
1529 /* Update remembered end of sequence
1530 in case we added an insn at the end. */
1531 stack->last = get_last_insn ();
1535 /* Scan all waiting RTL_EXPRs too. */
1536 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1538 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1539 if (seq != const0_rtx && seq != 0)
1541 push_to_sequence (seq);
1542 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1548 volatile_ok = save_volatile_ok;
1551 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1552 some part of an insn. Return a struct fixup_replacement whose OLD
1553 value is equal to X. Allocate a new structure if no such entry exists. */
1555 static struct fixup_replacement *
1556 find_fixup_replacement (struct fixup_replacement **replacements, rtx x)
1558 struct fixup_replacement *p;
1560 /* See if we have already replaced this. */
1561 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1566 p = xmalloc (sizeof (struct fixup_replacement));
1569 p->next = *replacements;
1576 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1577 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1578 for the current function. MAY_SHARE is either a MEM that is not
1579 to be unshared or a list of them. */
1582 fixup_var_refs_insns (rtx insn, rtx var, enum machine_mode promoted_mode,
1583 int unsignedp, int toplevel, rtx may_share)
1587 /* fixup_var_refs_insn might modify insn, so save its next
1589 rtx next = NEXT_INSN (insn);
1591 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1592 the three sequences they (potentially) contain, and process
1593 them recursively. The CALL_INSN itself is not interesting. */
1595 if (GET_CODE (insn) == CALL_INSN
1596 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1600 /* Look at the Normal call, sibling call and tail recursion
1601 sequences attached to the CALL_PLACEHOLDER. */
1602 for (i = 0; i < 3; i++)
1604 rtx seq = XEXP (PATTERN (insn), i);
1607 push_to_sequence (seq);
1608 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1610 XEXP (PATTERN (insn), i) = get_insns ();
1616 else if (INSN_P (insn))
1617 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1624 /* Look up the insns which reference VAR in HT and fix them up. Other
1625 arguments are the same as fixup_var_refs_insns.
1627 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1628 because the hash table will point straight to the interesting insn
1629 (inside the CALL_PLACEHOLDER). */
1632 fixup_var_refs_insns_with_hash (htab_t ht, rtx var, enum machine_mode promoted_mode,
1633 int unsignedp, rtx may_share)
1635 struct insns_for_mem_entry tmp;
1636 struct insns_for_mem_entry *ime;
1640 ime = htab_find (ht, &tmp);
1641 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1642 if (INSN_P (XEXP (insn_list, 0)))
1643 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1644 unsignedp, 1, may_share);
1648 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1649 the insn under examination, VAR is the variable to fix up
1650 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1651 TOPLEVEL is nonzero if this is the main insn chain for this
1655 fixup_var_refs_insn (rtx insn, rtx var, enum machine_mode promoted_mode,
1656 int unsignedp, int toplevel, rtx no_share)
1659 rtx set, prev, prev_set;
1662 /* Remember the notes in case we delete the insn. */
1663 note = REG_NOTES (insn);
1665 /* If this is a CLOBBER of VAR, delete it.
1667 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1668 and REG_RETVAL notes too. */
1669 if (GET_CODE (PATTERN (insn)) == CLOBBER
1670 && (XEXP (PATTERN (insn), 0) == var
1671 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1672 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1673 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1675 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1676 /* The REG_LIBCALL note will go away since we are going to
1677 turn INSN into a NOTE, so just delete the
1678 corresponding REG_RETVAL note. */
1679 remove_note (XEXP (note, 0),
1680 find_reg_note (XEXP (note, 0), REG_RETVAL,
1686 /* The insn to load VAR from a home in the arglist
1687 is now a no-op. When we see it, just delete it.
1688 Similarly if this is storing VAR from a register from which
1689 it was loaded in the previous insn. This will occur
1690 when an ADDRESSOF was made for an arglist slot. */
1692 && (set = single_set (insn)) != 0
1693 && SET_DEST (set) == var
1694 /* If this represents the result of an insn group,
1695 don't delete the insn. */
1696 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1697 && (rtx_equal_p (SET_SRC (set), var)
1698 || (GET_CODE (SET_SRC (set)) == REG
1699 && (prev = prev_nonnote_insn (insn)) != 0
1700 && (prev_set = single_set (prev)) != 0
1701 && SET_DEST (prev_set) == SET_SRC (set)
1702 && rtx_equal_p (SET_SRC (prev_set), var))))
1708 struct fixup_replacement *replacements = 0;
1709 rtx next_insn = NEXT_INSN (insn);
1711 if (SMALL_REGISTER_CLASSES)
1713 /* If the insn that copies the results of a CALL_INSN
1714 into a pseudo now references VAR, we have to use an
1715 intermediate pseudo since we want the life of the
1716 return value register to be only a single insn.
1718 If we don't use an intermediate pseudo, such things as
1719 address computations to make the address of VAR valid
1720 if it is not can be placed between the CALL_INSN and INSN.
1722 To make sure this doesn't happen, we record the destination
1723 of the CALL_INSN and see if the next insn uses both that
1726 if (call_dest != 0 && GET_CODE (insn) == INSN
1727 && reg_mentioned_p (var, PATTERN (insn))
1728 && reg_mentioned_p (call_dest, PATTERN (insn)))
1730 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1732 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1734 PATTERN (insn) = replace_rtx (PATTERN (insn),
1738 if (GET_CODE (insn) == CALL_INSN
1739 && GET_CODE (PATTERN (insn)) == SET)
1740 call_dest = SET_DEST (PATTERN (insn));
1741 else if (GET_CODE (insn) == CALL_INSN
1742 && GET_CODE (PATTERN (insn)) == PARALLEL
1743 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1744 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1749 /* See if we have to do anything to INSN now that VAR is in
1750 memory. If it needs to be loaded into a pseudo, use a single
1751 pseudo for the entire insn in case there is a MATCH_DUP
1752 between two operands. We pass a pointer to the head of
1753 a list of struct fixup_replacements. If fixup_var_refs_1
1754 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1755 it will record them in this list.
1757 If it allocated a pseudo for any replacement, we copy into
1760 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1761 &replacements, no_share);
1763 /* If this is last_parm_insn, and any instructions were output
1764 after it to fix it up, then we must set last_parm_insn to
1765 the last such instruction emitted. */
1766 if (insn == last_parm_insn)
1767 last_parm_insn = PREV_INSN (next_insn);
1769 while (replacements)
1771 struct fixup_replacement *next;
1773 if (GET_CODE (replacements->new) == REG)
1778 /* OLD might be a (subreg (mem)). */
1779 if (GET_CODE (replacements->old) == SUBREG)
1781 = fixup_memory_subreg (replacements->old, insn,
1785 = fixup_stack_1 (replacements->old, insn);
1787 insert_before = insn;
1789 /* If we are changing the mode, do a conversion.
1790 This might be wasteful, but combine.c will
1791 eliminate much of the waste. */
1793 if (GET_MODE (replacements->new)
1794 != GET_MODE (replacements->old))
1797 convert_move (replacements->new,
1798 replacements->old, unsignedp);
1803 seq = gen_move_insn (replacements->new,
1806 emit_insn_before (seq, insert_before);
1809 next = replacements->next;
1810 free (replacements);
1811 replacements = next;
1815 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1816 But don't touch other insns referred to by reg-notes;
1817 we will get them elsewhere. */
1820 if (GET_CODE (note) != INSN_LIST)
1822 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1824 note = XEXP (note, 1);
1828 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1829 See if the rtx expression at *LOC in INSN needs to be changed.
1831 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1832 contain a list of original rtx's and replacements. If we find that we need
1833 to modify this insn by replacing a memory reference with a pseudo or by
1834 making a new MEM to implement a SUBREG, we consult that list to see if
1835 we have already chosen a replacement. If none has already been allocated,
1836 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1837 or the SUBREG, as appropriate, to the pseudo. */
1840 fixup_var_refs_1 (rtx var, enum machine_mode promoted_mode, rtx *loc, rtx insn,
1841 struct fixup_replacement **replacements, rtx no_share)
1845 RTX_CODE code = GET_CODE (x);
1848 struct fixup_replacement *replacement;
1853 if (XEXP (x, 0) == var)
1855 /* Prevent sharing of rtl that might lose. */
1856 rtx sub = copy_rtx (XEXP (var, 0));
1858 if (! validate_change (insn, loc, sub, 0))
1860 rtx y = gen_reg_rtx (GET_MODE (sub));
1863 /* We should be able to replace with a register or all is lost.
1864 Note that we can't use validate_change to verify this, since
1865 we're not caring for replacing all dups simultaneously. */
1866 if (! validate_replace_rtx (*loc, y, insn))
1869 /* Careful! First try to recognize a direct move of the
1870 value, mimicking how things are done in gen_reload wrt
1871 PLUS. Consider what happens when insn is a conditional
1872 move instruction and addsi3 clobbers flags. */
1875 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1879 if (recog_memoized (new_insn) < 0)
1881 /* That failed. Fall back on force_operand and hope. */
1884 sub = force_operand (sub, y);
1886 emit_insn (gen_move_insn (y, sub));
1892 /* Don't separate setter from user. */
1893 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1894 insn = PREV_INSN (insn);
1897 emit_insn_before (seq, insn);
1905 /* If we already have a replacement, use it. Otherwise,
1906 try to fix up this address in case it is invalid. */
1908 replacement = find_fixup_replacement (replacements, var);
1909 if (replacement->new)
1911 *loc = replacement->new;
1915 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1917 /* Unless we are forcing memory to register or we changed the mode,
1918 we can leave things the way they are if the insn is valid. */
1920 INSN_CODE (insn) = -1;
1921 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1922 && recog_memoized (insn) >= 0)
1925 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1929 /* If X contains VAR, we need to unshare it here so that we update
1930 each occurrence separately. But all identical MEMs in one insn
1931 must be replaced with the same rtx because of the possibility of
1934 if (reg_mentioned_p (var, x))
1936 replacement = find_fixup_replacement (replacements, x);
1937 if (replacement->new == 0)
1938 replacement->new = copy_most_rtx (x, no_share);
1940 *loc = x = replacement->new;
1941 code = GET_CODE (x);
1958 /* Note that in some cases those types of expressions are altered
1959 by optimize_bit_field, and do not survive to get here. */
1960 if (XEXP (x, 0) == var
1961 || (GET_CODE (XEXP (x, 0)) == SUBREG
1962 && SUBREG_REG (XEXP (x, 0)) == var))
1964 /* Get TEM as a valid MEM in the mode presently in the insn.
1966 We don't worry about the possibility of MATCH_DUP here; it
1967 is highly unlikely and would be tricky to handle. */
1970 if (GET_CODE (tem) == SUBREG)
1972 if (GET_MODE_BITSIZE (GET_MODE (tem))
1973 > GET_MODE_BITSIZE (GET_MODE (var)))
1975 replacement = find_fixup_replacement (replacements, var);
1976 if (replacement->new == 0)
1977 replacement->new = gen_reg_rtx (GET_MODE (var));
1978 SUBREG_REG (tem) = replacement->new;
1980 /* The following code works only if we have a MEM, so we
1981 need to handle the subreg here. We directly substitute
1982 it assuming that a subreg must be OK here. We already
1983 scheduled a replacement to copy the mem into the
1989 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
1992 tem = fixup_stack_1 (tem, insn);
1994 /* Unless we want to load from memory, get TEM into the proper mode
1995 for an extract from memory. This can only be done if the
1996 extract is at a constant position and length. */
1998 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1999 && GET_CODE (XEXP (x, 2)) == CONST_INT
2000 && ! mode_dependent_address_p (XEXP (tem, 0))
2001 && ! MEM_VOLATILE_P (tem))
2003 enum machine_mode wanted_mode = VOIDmode;
2004 enum machine_mode is_mode = GET_MODE (tem);
2005 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2007 if (GET_CODE (x) == ZERO_EXTRACT)
2009 enum machine_mode new_mode
2010 = mode_for_extraction (EP_extzv, 1);
2011 if (new_mode != MAX_MACHINE_MODE)
2012 wanted_mode = new_mode;
2014 else if (GET_CODE (x) == SIGN_EXTRACT)
2016 enum machine_mode new_mode
2017 = mode_for_extraction (EP_extv, 1);
2018 if (new_mode != MAX_MACHINE_MODE)
2019 wanted_mode = new_mode;
2022 /* If we have a narrower mode, we can do something. */
2023 if (wanted_mode != VOIDmode
2024 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2026 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2027 rtx old_pos = XEXP (x, 2);
2030 /* If the bytes and bits are counted differently, we
2031 must adjust the offset. */
2032 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2033 offset = (GET_MODE_SIZE (is_mode)
2034 - GET_MODE_SIZE (wanted_mode) - offset);
2036 pos %= GET_MODE_BITSIZE (wanted_mode);
2038 newmem = adjust_address_nv (tem, wanted_mode, offset);
2040 /* Make the change and see if the insn remains valid. */
2041 INSN_CODE (insn) = -1;
2042 XEXP (x, 0) = newmem;
2043 XEXP (x, 2) = GEN_INT (pos);
2045 if (recog_memoized (insn) >= 0)
2048 /* Otherwise, restore old position. XEXP (x, 0) will be
2050 XEXP (x, 2) = old_pos;
2054 /* If we get here, the bitfield extract insn can't accept a memory
2055 reference. Copy the input into a register. */
2057 tem1 = gen_reg_rtx (GET_MODE (tem));
2058 emit_insn_before (gen_move_insn (tem1, tem), insn);
2065 if (SUBREG_REG (x) == var)
2067 /* If this is a special SUBREG made because VAR was promoted
2068 from a wider mode, replace it with VAR and call ourself
2069 recursively, this time saying that the object previously
2070 had its current mode (by virtue of the SUBREG). */
2072 if (SUBREG_PROMOTED_VAR_P (x))
2075 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2080 /* If this SUBREG makes VAR wider, it has become a paradoxical
2081 SUBREG with VAR in memory, but these aren't allowed at this
2082 stage of the compilation. So load VAR into a pseudo and take
2083 a SUBREG of that pseudo. */
2084 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2086 replacement = find_fixup_replacement (replacements, var);
2087 if (replacement->new == 0)
2088 replacement->new = gen_reg_rtx (promoted_mode);
2089 SUBREG_REG (x) = replacement->new;
2093 /* See if we have already found a replacement for this SUBREG.
2094 If so, use it. Otherwise, make a MEM and see if the insn
2095 is recognized. If not, or if we should force MEM into a register,
2096 make a pseudo for this SUBREG. */
2097 replacement = find_fixup_replacement (replacements, x);
2098 if (replacement->new)
2100 enum machine_mode mode = GET_MODE (x);
2101 *loc = replacement->new;
2103 /* Careful! We may have just replaced a SUBREG by a MEM, which
2104 means that the insn may have become invalid again. We can't
2105 in this case make a new replacement since we already have one
2106 and we must deal with MATCH_DUPs. */
2107 if (GET_CODE (replacement->new) == MEM)
2109 INSN_CODE (insn) = -1;
2110 if (recog_memoized (insn) >= 0)
2113 fixup_var_refs_1 (replacement->new, mode, &PATTERN (insn),
2114 insn, replacements, no_share);
2120 replacement->new = *loc = fixup_memory_subreg (x, insn,
2123 INSN_CODE (insn) = -1;
2124 if (! flag_force_mem && recog_memoized (insn) >= 0)
2127 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2133 /* First do special simplification of bit-field references. */
2134 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2135 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2136 optimize_bit_field (x, insn, 0);
2137 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2138 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2139 optimize_bit_field (x, insn, 0);
2141 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2142 into a register and then store it back out. */
2143 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2144 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2145 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2146 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2147 > GET_MODE_SIZE (GET_MODE (var))))
2149 replacement = find_fixup_replacement (replacements, var);
2150 if (replacement->new == 0)
2151 replacement->new = gen_reg_rtx (GET_MODE (var));
2153 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2154 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2157 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2158 insn into a pseudo and store the low part of the pseudo into VAR. */
2159 if (GET_CODE (SET_DEST (x)) == SUBREG
2160 && SUBREG_REG (SET_DEST (x)) == var
2161 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2162 > GET_MODE_SIZE (GET_MODE (var))))
2164 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2165 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2172 rtx dest = SET_DEST (x);
2173 rtx src = SET_SRC (x);
2174 rtx outerdest = dest;
2176 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2177 || GET_CODE (dest) == SIGN_EXTRACT
2178 || GET_CODE (dest) == ZERO_EXTRACT)
2179 dest = XEXP (dest, 0);
2181 if (GET_CODE (src) == SUBREG)
2182 src = SUBREG_REG (src);
2184 /* If VAR does not appear at the top level of the SET
2185 just scan the lower levels of the tree. */
2187 if (src != var && dest != var)
2190 /* We will need to rerecognize this insn. */
2191 INSN_CODE (insn) = -1;
2193 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2194 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2196 /* Since this case will return, ensure we fixup all the
2198 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2199 insn, replacements, no_share);
2200 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2201 insn, replacements, no_share);
2202 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2203 insn, replacements, no_share);
2205 tem = XEXP (outerdest, 0);
2207 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2208 that may appear inside a ZERO_EXTRACT.
2209 This was legitimate when the MEM was a REG. */
2210 if (GET_CODE (tem) == SUBREG
2211 && SUBREG_REG (tem) == var)
2212 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2214 tem = fixup_stack_1 (tem, insn);
2216 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2217 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2218 && ! mode_dependent_address_p (XEXP (tem, 0))
2219 && ! MEM_VOLATILE_P (tem))
2221 enum machine_mode wanted_mode;
2222 enum machine_mode is_mode = GET_MODE (tem);
2223 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2225 wanted_mode = mode_for_extraction (EP_insv, 0);
2227 /* If we have a narrower mode, we can do something. */
2228 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2230 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2231 rtx old_pos = XEXP (outerdest, 2);
2234 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2235 offset = (GET_MODE_SIZE (is_mode)
2236 - GET_MODE_SIZE (wanted_mode) - offset);
2238 pos %= GET_MODE_BITSIZE (wanted_mode);
2240 newmem = adjust_address_nv (tem, wanted_mode, offset);
2242 /* Make the change and see if the insn remains valid. */
2243 INSN_CODE (insn) = -1;
2244 XEXP (outerdest, 0) = newmem;
2245 XEXP (outerdest, 2) = GEN_INT (pos);
2247 if (recog_memoized (insn) >= 0)
2250 /* Otherwise, restore old position. XEXP (x, 0) will be
2252 XEXP (outerdest, 2) = old_pos;
2256 /* If we get here, the bit-field store doesn't allow memory
2257 or isn't located at a constant position. Load the value into
2258 a register, do the store, and put it back into memory. */
2260 tem1 = gen_reg_rtx (GET_MODE (tem));
2261 emit_insn_before (gen_move_insn (tem1, tem), insn);
2262 emit_insn_after (gen_move_insn (tem, tem1), insn);
2263 XEXP (outerdest, 0) = tem1;
2267 /* STRICT_LOW_PART is a no-op on memory references
2268 and it can cause combinations to be unrecognizable,
2271 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2272 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2274 /* A valid insn to copy VAR into or out of a register
2275 must be left alone, to avoid an infinite loop here.
2276 If the reference to VAR is by a subreg, fix that up,
2277 since SUBREG is not valid for a memref.
2278 Also fix up the address of the stack slot.
2280 Note that we must not try to recognize the insn until
2281 after we know that we have valid addresses and no
2282 (subreg (mem ...) ...) constructs, since these interfere
2283 with determining the validity of the insn. */
2285 if ((SET_SRC (x) == var
2286 || (GET_CODE (SET_SRC (x)) == SUBREG
2287 && SUBREG_REG (SET_SRC (x)) == var))
2288 && (GET_CODE (SET_DEST (x)) == REG
2289 || (GET_CODE (SET_DEST (x)) == SUBREG
2290 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2291 && GET_MODE (var) == promoted_mode
2292 && x == single_set (insn))
2296 if (GET_CODE (SET_SRC (x)) == SUBREG
2297 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2298 > GET_MODE_SIZE (GET_MODE (var))))
2300 /* This (subreg VAR) is now a paradoxical subreg. We need
2301 to replace VAR instead of the subreg. */
2302 replacement = find_fixup_replacement (replacements, var);
2303 if (replacement->new == NULL_RTX)
2304 replacement->new = gen_reg_rtx (GET_MODE (var));
2305 SUBREG_REG (SET_SRC (x)) = replacement->new;
2309 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2310 if (replacement->new)
2311 SET_SRC (x) = replacement->new;
2312 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2313 SET_SRC (x) = replacement->new
2314 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2317 SET_SRC (x) = replacement->new
2318 = fixup_stack_1 (SET_SRC (x), insn);
2321 if (recog_memoized (insn) >= 0)
2324 /* INSN is not valid, but we know that we want to
2325 copy SET_SRC (x) to SET_DEST (x) in some way. So
2326 we generate the move and see whether it requires more
2327 than one insn. If it does, we emit those insns and
2328 delete INSN. Otherwise, we can just replace the pattern
2329 of INSN; we have already verified above that INSN has
2330 no other function that to do X. */
2332 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2333 if (NEXT_INSN (pat) != NULL_RTX)
2335 last = emit_insn_before (pat, insn);
2337 /* INSN might have REG_RETVAL or other important notes, so
2338 we need to store the pattern of the last insn in the
2339 sequence into INSN similarly to the normal case. LAST
2340 should not have REG_NOTES, but we allow them if INSN has
2342 if (REG_NOTES (last) && REG_NOTES (insn))
2344 if (REG_NOTES (last))
2345 REG_NOTES (insn) = REG_NOTES (last);
2346 PATTERN (insn) = PATTERN (last);
2351 PATTERN (insn) = PATTERN (pat);
2356 if ((SET_DEST (x) == var
2357 || (GET_CODE (SET_DEST (x)) == SUBREG
2358 && SUBREG_REG (SET_DEST (x)) == var))
2359 && (GET_CODE (SET_SRC (x)) == REG
2360 || (GET_CODE (SET_SRC (x)) == SUBREG
2361 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2362 && GET_MODE (var) == promoted_mode
2363 && x == single_set (insn))
2367 if (GET_CODE (SET_DEST (x)) == SUBREG)
2368 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2371 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2373 if (recog_memoized (insn) >= 0)
2376 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2377 if (NEXT_INSN (pat) != NULL_RTX)
2379 last = emit_insn_before (pat, insn);
2381 /* INSN might have REG_RETVAL or other important notes, so
2382 we need to store the pattern of the last insn in the
2383 sequence into INSN similarly to the normal case. LAST
2384 should not have REG_NOTES, but we allow them if INSN has
2386 if (REG_NOTES (last) && REG_NOTES (insn))
2388 if (REG_NOTES (last))
2389 REG_NOTES (insn) = REG_NOTES (last);
2390 PATTERN (insn) = PATTERN (last);
2395 PATTERN (insn) = PATTERN (pat);
2400 /* Otherwise, storing into VAR must be handled specially
2401 by storing into a temporary and copying that into VAR
2402 with a new insn after this one. Note that this case
2403 will be used when storing into a promoted scalar since
2404 the insn will now have different modes on the input
2405 and output and hence will be invalid (except for the case
2406 of setting it to a constant, which does not need any
2407 change if it is valid). We generate extra code in that case,
2408 but combine.c will eliminate it. */
2413 rtx fixeddest = SET_DEST (x);
2414 enum machine_mode temp_mode;
2416 /* STRICT_LOW_PART can be discarded, around a MEM. */
2417 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2418 fixeddest = XEXP (fixeddest, 0);
2419 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2420 if (GET_CODE (fixeddest) == SUBREG)
2422 fixeddest = fixup_memory_subreg (fixeddest, insn,
2424 temp_mode = GET_MODE (fixeddest);
2428 fixeddest = fixup_stack_1 (fixeddest, insn);
2429 temp_mode = promoted_mode;
2432 temp = gen_reg_rtx (temp_mode);
2434 emit_insn_after (gen_move_insn (fixeddest,
2435 gen_lowpart (GET_MODE (fixeddest),
2439 SET_DEST (x) = temp;
2447 /* Nothing special about this RTX; fix its operands. */
2449 fmt = GET_RTX_FORMAT (code);
2450 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2453 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2455 else if (fmt[i] == 'E')
2458 for (j = 0; j < XVECLEN (x, i); j++)
2459 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2460 insn, replacements, no_share);
2465 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2466 The REG was placed on the stack, so X now has the form (SUBREG:m1
2469 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2470 must be emitted to compute NEWADDR, put them before INSN.
2472 UNCRITICAL nonzero means accept paradoxical subregs.
2473 This is used for subregs found inside REG_NOTES. */
2476 fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode, int uncritical)
2479 rtx mem = SUBREG_REG (x);
2480 rtx addr = XEXP (mem, 0);
2481 enum machine_mode mode = GET_MODE (x);
2484 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2485 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2488 offset = SUBREG_BYTE (x);
2489 if (BYTES_BIG_ENDIAN)
2490 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2491 the offset so that it points to the right location within the
2493 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2495 if (!flag_force_addr
2496 && memory_address_p (mode, plus_constant (addr, offset)))
2497 /* Shortcut if no insns need be emitted. */
2498 return adjust_address (mem, mode, offset);
2501 result = adjust_address (mem, mode, offset);
2505 emit_insn_before (seq, insn);
2509 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2510 Replace subexpressions of X in place.
2511 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2512 Otherwise return X, with its contents possibly altered.
2514 INSN, PROMOTED_MODE and UNCRITICAL are as for
2515 fixup_memory_subreg. */
2518 walk_fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode,
2528 code = GET_CODE (x);
2530 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2531 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2533 /* Nothing special about this RTX; fix its operands. */
2535 fmt = GET_RTX_FORMAT (code);
2536 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2539 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2540 promoted_mode, uncritical);
2541 else if (fmt[i] == 'E')
2544 for (j = 0; j < XVECLEN (x, i); j++)
2546 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2547 promoted_mode, uncritical);
2553 /* For each memory ref within X, if it refers to a stack slot
2554 with an out of range displacement, put the address in a temp register
2555 (emitting new insns before INSN to load these registers)
2556 and alter the memory ref to use that register.
2557 Replace each such MEM rtx with a copy, to avoid clobberage. */
2560 fixup_stack_1 (rtx x, rtx insn)
2563 RTX_CODE code = GET_CODE (x);
2568 rtx ad = XEXP (x, 0);
2569 /* If we have address of a stack slot but it's not valid
2570 (displacement is too large), compute the sum in a register. */
2571 if (GET_CODE (ad) == PLUS
2572 && GET_CODE (XEXP (ad, 0)) == REG
2573 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2574 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2575 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2576 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2577 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2579 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2580 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2581 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2582 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2585 if (memory_address_p (GET_MODE (x), ad))
2589 temp = copy_to_reg (ad);
2592 emit_insn_before (seq, insn);
2593 return replace_equiv_address (x, temp);
2598 fmt = GET_RTX_FORMAT (code);
2599 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2602 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2603 else if (fmt[i] == 'E')
2606 for (j = 0; j < XVECLEN (x, i); j++)
2607 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2613 /* Optimization: a bit-field instruction whose field
2614 happens to be a byte or halfword in memory
2615 can be changed to a move instruction.
2617 We call here when INSN is an insn to examine or store into a bit-field.
2618 BODY is the SET-rtx to be altered.
2620 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2621 (Currently this is called only from function.c, and EQUIV_MEM
2625 optimize_bit_field (rtx body, rtx insn, rtx *equiv_mem)
2630 enum machine_mode mode;
2632 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2633 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2634 bitfield = SET_DEST (body), destflag = 1;
2636 bitfield = SET_SRC (body), destflag = 0;
2638 /* First check that the field being stored has constant size and position
2639 and is in fact a byte or halfword suitably aligned. */
2641 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2642 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2643 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2645 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2649 /* Now check that the containing word is memory, not a register,
2650 and that it is safe to change the machine mode. */
2652 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2653 memref = XEXP (bitfield, 0);
2654 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2656 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2657 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2658 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2659 memref = SUBREG_REG (XEXP (bitfield, 0));
2660 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2662 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2663 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2666 && ! mode_dependent_address_p (XEXP (memref, 0))
2667 && ! MEM_VOLATILE_P (memref))
2669 /* Now adjust the address, first for any subreg'ing
2670 that we are now getting rid of,
2671 and then for which byte of the word is wanted. */
2673 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2676 /* Adjust OFFSET to count bits from low-address byte. */
2677 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2678 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2679 - offset - INTVAL (XEXP (bitfield, 1)));
2681 /* Adjust OFFSET to count bytes from low-address byte. */
2682 offset /= BITS_PER_UNIT;
2683 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2685 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2686 / UNITS_PER_WORD) * UNITS_PER_WORD;
2687 if (BYTES_BIG_ENDIAN)
2688 offset -= (MIN (UNITS_PER_WORD,
2689 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2690 - MIN (UNITS_PER_WORD,
2691 GET_MODE_SIZE (GET_MODE (memref))));
2695 memref = adjust_address (memref, mode, offset);
2696 insns = get_insns ();
2698 emit_insn_before (insns, insn);
2700 /* Store this memory reference where
2701 we found the bit field reference. */
2705 validate_change (insn, &SET_DEST (body), memref, 1);
2706 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2708 rtx src = SET_SRC (body);
2709 while (GET_CODE (src) == SUBREG
2710 && SUBREG_BYTE (src) == 0)
2711 src = SUBREG_REG (src);
2712 if (GET_MODE (src) != GET_MODE (memref))
2713 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2714 validate_change (insn, &SET_SRC (body), src, 1);
2716 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2717 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2718 /* This shouldn't happen because anything that didn't have
2719 one of these modes should have got converted explicitly
2720 and then referenced through a subreg.
2721 This is so because the original bit-field was
2722 handled by agg_mode and so its tree structure had
2723 the same mode that memref now has. */
2728 rtx dest = SET_DEST (body);
2730 while (GET_CODE (dest) == SUBREG
2731 && SUBREG_BYTE (dest) == 0
2732 && (GET_MODE_CLASS (GET_MODE (dest))
2733 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2734 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2736 dest = SUBREG_REG (dest);
2738 validate_change (insn, &SET_DEST (body), dest, 1);
2740 if (GET_MODE (dest) == GET_MODE (memref))
2741 validate_change (insn, &SET_SRC (body), memref, 1);
2744 /* Convert the mem ref to the destination mode. */
2745 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2748 convert_move (newreg, memref,
2749 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2753 validate_change (insn, &SET_SRC (body), newreg, 1);
2757 /* See if we can convert this extraction or insertion into
2758 a simple move insn. We might not be able to do so if this
2759 was, for example, part of a PARALLEL.
2761 If we succeed, write out any needed conversions. If we fail,
2762 it is hard to guess why we failed, so don't do anything
2763 special; just let the optimization be suppressed. */
2765 if (apply_change_group () && seq)
2766 emit_insn_before (seq, insn);
2771 /* These routines are responsible for converting virtual register references
2772 to the actual hard register references once RTL generation is complete.
2774 The following four variables are used for communication between the
2775 routines. They contain the offsets of the virtual registers from their
2776 respective hard registers. */
2778 static int in_arg_offset;
2779 static int var_offset;
2780 static int dynamic_offset;
2781 static int out_arg_offset;
2782 static int cfa_offset;
2784 /* In most machines, the stack pointer register is equivalent to the bottom
2787 #ifndef STACK_POINTER_OFFSET
2788 #define STACK_POINTER_OFFSET 0
2791 /* If not defined, pick an appropriate default for the offset of dynamically
2792 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2793 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2795 #ifndef STACK_DYNAMIC_OFFSET
2797 /* The bottom of the stack points to the actual arguments. If
2798 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2799 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2800 stack space for register parameters is not pushed by the caller, but
2801 rather part of the fixed stack areas and hence not included in
2802 `current_function_outgoing_args_size'. Nevertheless, we must allow
2803 for it when allocating stack dynamic objects. */
2805 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2806 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2807 ((ACCUMULATE_OUTGOING_ARGS \
2808 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2809 + (STACK_POINTER_OFFSET)) \
2812 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2813 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2814 + (STACK_POINTER_OFFSET))
2818 /* On most machines, the CFA coincides with the first incoming parm. */
2820 #ifndef ARG_POINTER_CFA_OFFSET
2821 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2824 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2825 had its address taken. DECL is the decl or SAVE_EXPR for the
2826 object stored in the register, for later use if we do need to force
2827 REG into the stack. REG is overwritten by the MEM like in
2828 put_reg_into_stack. RESCAN is true if previously emitted
2829 instructions must be rescanned and modified now that the REG has
2830 been transformed. */
2833 gen_mem_addressof (rtx reg, tree decl, int rescan)
2835 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2838 /* Calculate this before we start messing with decl's RTL. */
2839 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2841 /* If the original REG was a user-variable, then so is the REG whose
2842 address is being taken. Likewise for unchanging. */
2843 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2844 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2846 PUT_CODE (reg, MEM);
2847 MEM_VOLATILE_P (reg) = 0;
2848 MEM_ATTRS (reg) = 0;
2853 tree type = TREE_TYPE (decl);
2854 enum machine_mode decl_mode
2855 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2856 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2857 : DECL_RTL_IF_SET (decl));
2859 PUT_MODE (reg, decl_mode);
2861 /* Clear DECL_RTL momentarily so functions below will work
2862 properly, then set it again. */
2863 if (DECL_P (decl) && decl_rtl == reg)
2864 SET_DECL_RTL (decl, 0);
2866 set_mem_attributes (reg, decl, 1);
2867 set_mem_alias_set (reg, set);
2869 if (DECL_P (decl) && decl_rtl == reg)
2870 SET_DECL_RTL (decl, reg);
2873 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0)))
2874 fixup_var_refs (reg, GET_MODE (reg), TYPE_UNSIGNED (type), reg, 0);
2878 /* This can only happen during reload. Clear the same flag bits as
2880 RTX_UNCHANGING_P (reg) = 0;
2881 MEM_IN_STRUCT_P (reg) = 0;
2882 MEM_SCALAR_P (reg) = 0;
2884 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2890 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2893 flush_addressof (tree decl)
2895 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2896 && DECL_RTL (decl) != 0
2897 && GET_CODE (DECL_RTL (decl)) == MEM
2898 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2899 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2900 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2903 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2906 put_addressof_into_stack (rtx r, htab_t ht)
2909 bool volatile_p, used_p;
2911 rtx reg = XEXP (r, 0);
2913 if (GET_CODE (reg) != REG)
2916 decl = ADDRESSOF_DECL (r);
2919 type = TREE_TYPE (decl);
2920 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2921 && TREE_THIS_VOLATILE (decl));
2922 used_p = (TREE_USED (decl)
2923 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2932 put_reg_into_stack (0, reg, type, GET_MODE (reg), ADDRESSOF_REGNO (r),
2933 volatile_p, used_p, false, ht);
2936 /* List of replacements made below in purge_addressof_1 when creating
2937 bitfield insertions. */
2938 static rtx purge_bitfield_addressof_replacements;
2940 /* List of replacements made below in purge_addressof_1 for patterns
2941 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2942 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2943 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2944 enough in complex cases, e.g. when some field values can be
2945 extracted by usage MEM with narrower mode. */
2946 static rtx purge_addressof_replacements;
2948 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2949 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2950 the stack. If the function returns FALSE then the replacement could not
2951 be made. If MAY_POSTPONE is true and we would not put the addressof
2952 to stack, postpone processing of the insn. */
2955 purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
2963 bool libcall = false;
2965 /* Re-start here to avoid recursion in common cases. */
2972 /* Is this a libcall? */
2974 libcall = REG_NOTE_KIND (*loc) == REG_RETVAL;
2976 code = GET_CODE (x);
2978 /* If we don't return in any of the cases below, we will recurse inside
2979 the RTX, which will normally result in any ADDRESSOF being forced into
2983 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1,
2985 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0,
2989 else if (code == ADDRESSOF)
2993 if (GET_CODE (XEXP (x, 0)) != MEM)
2994 put_addressof_into_stack (x, ht);
2996 /* We must create a copy of the rtx because it was created by
2997 overwriting a REG rtx which is always shared. */
2998 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2999 if (validate_change (insn, loc, sub, 0)
3000 || validate_replace_rtx (x, sub, insn))
3005 /* If SUB is a hard or virtual register, try it as a pseudo-register.
3006 Otherwise, perhaps SUB is an expression, so generate code to compute
3008 if (GET_CODE (sub) == REG && REGNO (sub) <= LAST_VIRTUAL_REGISTER)
3009 sub = copy_to_reg (sub);
3011 sub = force_operand (sub, NULL_RTX);
3013 if (! validate_change (insn, loc, sub, 0)
3014 && ! validate_replace_rtx (x, sub, insn))
3017 insns = get_insns ();
3019 emit_insn_before (insns, insn);
3023 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3025 rtx sub = XEXP (XEXP (x, 0), 0);
3027 if (GET_CODE (sub) == MEM)
3028 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3029 else if (GET_CODE (sub) == REG
3030 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3032 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3034 int size_x, size_sub;
3038 /* Postpone for now, so that we do not emit bitfield arithmetics
3039 unless there is some benefit from it. */
3040 if (!postponed_insns || XEXP (postponed_insns, 0) != insn)
3041 postponed_insns = alloc_INSN_LIST (insn, postponed_insns);
3047 /* When processing REG_NOTES look at the list of
3048 replacements done on the insn to find the register that X
3052 for (tem = purge_bitfield_addressof_replacements;
3054 tem = XEXP (XEXP (tem, 1), 1))
3055 if (rtx_equal_p (x, XEXP (tem, 0)))
3057 *loc = XEXP (XEXP (tem, 1), 0);
3061 /* See comment for purge_addressof_replacements. */
3062 for (tem = purge_addressof_replacements;
3064 tem = XEXP (XEXP (tem, 1), 1))
3065 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3067 rtx z = XEXP (XEXP (tem, 1), 0);
3069 if (GET_MODE (x) == GET_MODE (z)
3070 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3071 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3074 /* It can happen that the note may speak of things
3075 in a wider (or just different) mode than the
3076 code did. This is especially true of
3079 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3082 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3083 && (GET_MODE_SIZE (GET_MODE (x))
3084 > GET_MODE_SIZE (GET_MODE (z))))
3086 /* This can occur as a result in invalid
3087 pointer casts, e.g. float f; ...
3088 *(long long int *)&f.
3089 ??? We could emit a warning here, but
3090 without a line number that wouldn't be
3092 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3095 z = gen_lowpart (GET_MODE (x), z);
3101 /* When we are processing the REG_NOTES of the last instruction
3102 of a libcall, there will be typically no replacements
3103 for that insn; the replacements happened before, piecemeal
3104 fashion. OTOH we are not interested in the details of
3105 this for the REG_EQUAL note, we want to know the big picture,
3106 which can be succinctly described with a simple SUBREG.
3107 Note that removing the REG_EQUAL note is not an option
3108 on the last insn of a libcall, so we must do a replacement. */
3110 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
3112 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
3113 [0 S8 A32]), which can be expressed with a simple
3115 if ((GET_MODE_SIZE (GET_MODE (x))
3116 <= GET_MODE_SIZE (GET_MODE (sub)))
3117 /* Again, invalid pointer casts (as in
3118 compile/990203-1.c) can require paradoxical
3120 || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3121 && (GET_MODE_SIZE (GET_MODE (x))
3122 > GET_MODE_SIZE (GET_MODE (sub)))
3125 *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
3128 /* ??? Are there other cases we should handle? */
3130 /* Sometimes we may not be able to find the replacement. For
3131 example when the original insn was a MEM in a wider mode,
3132 and the note is part of a sign extension of a narrowed
3133 version of that MEM. Gcc testcase compile/990829-1.c can
3134 generate an example of this situation. Rather than complain
3135 we return false, which will prompt our caller to remove the
3140 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3141 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3143 /* Do not frob unchanging MEMs. If a later reference forces the
3144 pseudo to the stack, we can wind up with multiple writes to
3145 an unchanging memory, which is invalid. */
3146 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3149 /* Don't even consider working with paradoxical subregs,
3150 or the moral equivalent seen here. */
3151 else if (size_x <= size_sub
3152 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3154 /* Do a bitfield insertion to mirror what would happen
3161 rtx p = PREV_INSN (insn);
3164 val = gen_reg_rtx (GET_MODE (x));
3165 if (! validate_change (insn, loc, val, 0))
3167 /* Discard the current sequence and put the
3168 ADDRESSOF on stack. */
3174 emit_insn_before (seq, insn);
3175 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3179 store_bit_field (sub, size_x, 0, GET_MODE (x),
3180 val, GET_MODE_SIZE (GET_MODE (sub)));
3182 /* Make sure to unshare any shared rtl that store_bit_field
3183 might have created. */
3184 unshare_all_rtl_again (get_insns ());
3188 p = emit_insn_after (seq, insn);
3189 if (NEXT_INSN (insn))
3190 compute_insns_for_mem (NEXT_INSN (insn),
3191 p ? NEXT_INSN (p) : NULL_RTX,
3196 rtx p = PREV_INSN (insn);
3199 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3200 GET_MODE (x), GET_MODE (x),
3201 GET_MODE_SIZE (GET_MODE (sub)));
3203 if (! validate_change (insn, loc, val, 0))
3205 /* Discard the current sequence and put the
3206 ADDRESSOF on stack. */
3213 emit_insn_before (seq, insn);
3214 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3218 /* Remember the replacement so that the same one can be done
3219 on the REG_NOTES. */
3220 purge_bitfield_addressof_replacements
3221 = gen_rtx_EXPR_LIST (VOIDmode, x,
3224 purge_bitfield_addressof_replacements));
3226 /* We replaced with a reg -- all done. */
3231 else if (validate_change (insn, loc, sub, 0))
3233 /* Remember the replacement so that the same one can be done
3234 on the REG_NOTES. */
3235 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3239 for (tem = purge_addressof_replacements;
3241 tem = XEXP (XEXP (tem, 1), 1))
3242 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3244 XEXP (XEXP (tem, 1), 0) = sub;
3247 purge_addressof_replacements
3248 = gen_rtx_EXPR_LIST (VOIDmode, XEXP (x, 0),
3249 gen_rtx_EXPR_LIST (VOIDmode, sub,
3250 purge_addressof_replacements));
3258 /* Scan all subexpressions. */
3259 fmt = GET_RTX_FORMAT (code);
3260 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3263 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0,
3265 else if (*fmt == 'E')
3266 for (j = 0; j < XVECLEN (x, i); j++)
3267 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0,
3274 /* Return a hash value for K, a REG. */
3277 insns_for_mem_hash (const void *k)
3279 /* Use the address of the key for the hash value. */
3280 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3281 return htab_hash_pointer (m->key);
3284 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3287 insns_for_mem_comp (const void *k1, const void *k2)
3289 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3290 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3291 return m1->key == m2->key;
3294 struct insns_for_mem_walk_info
3296 /* The hash table that we are using to record which INSNs use which
3300 /* The INSN we are currently processing. */
3303 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3304 to find the insns that use the REGs in the ADDRESSOFs. */
3308 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3309 that might be used in an ADDRESSOF expression, record this INSN in
3310 the hash table given by DATA (which is really a pointer to an
3311 insns_for_mem_walk_info structure). */
3314 insns_for_mem_walk (rtx *r, void *data)
3316 struct insns_for_mem_walk_info *ifmwi
3317 = (struct insns_for_mem_walk_info *) data;
3318 struct insns_for_mem_entry tmp;
3319 tmp.insns = NULL_RTX;
3321 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3322 && GET_CODE (XEXP (*r, 0)) == REG)
3325 tmp.key = XEXP (*r, 0);
3326 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3329 *e = ggc_alloc (sizeof (tmp));
3330 memcpy (*e, &tmp, sizeof (tmp));
3333 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3335 struct insns_for_mem_entry *ifme;
3337 ifme = htab_find (ifmwi->ht, &tmp);
3339 /* If we have not already recorded this INSN, do so now. Since
3340 we process the INSNs in order, we know that if we have
3341 recorded it it must be at the front of the list. */
3342 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3343 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3350 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3351 which REGs in HT. */
3354 compute_insns_for_mem (rtx insns, rtx last_insn, htab_t ht)
3357 struct insns_for_mem_walk_info ifmwi;
3360 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3361 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3365 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3369 /* Helper function for purge_addressof called through for_each_rtx.
3370 Returns true iff the rtl is an ADDRESSOF. */
3373 is_addressof (rtx *rtl, void *data ATTRIBUTE_UNUSED)
3375 return GET_CODE (*rtl) == ADDRESSOF;
3378 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3379 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3383 purge_addressof (rtx insns)
3388 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3389 requires a fixup pass over the instruction stream to correct
3390 INSNs that depended on the REG being a REG, and not a MEM. But,
3391 these fixup passes are slow. Furthermore, most MEMs are not
3392 mentioned in very many instructions. So, we speed up the process
3393 by pre-calculating which REGs occur in which INSNs; that allows
3394 us to perform the fixup passes much more quickly. */
3395 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3396 compute_insns_for_mem (insns, NULL_RTX, ht);
3398 postponed_insns = NULL;
3400 for (insn = insns; insn; insn = NEXT_INSN (insn))
3403 if (! purge_addressof_1 (&PATTERN (insn), insn,
3404 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht))
3405 /* If we could not replace the ADDRESSOFs in the insn,
3406 something is wrong. */
3409 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht))
3411 /* If we could not replace the ADDRESSOFs in the insn's notes,
3412 we can just remove the offending notes instead. */
3415 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3417 /* If we find a REG_RETVAL note then the insn is a libcall.
3418 Such insns must have REG_EQUAL notes as well, in order
3419 for later passes of the compiler to work. So it is not
3420 safe to delete the notes here, and instead we abort. */
3421 if (REG_NOTE_KIND (note) == REG_RETVAL)
3423 if (for_each_rtx (¬e, is_addressof, NULL))
3424 remove_note (insn, note);
3429 /* Process the postponed insns. */
3430 while (postponed_insns)
3432 insn = XEXP (postponed_insns, 0);
3433 tmp = postponed_insns;
3434 postponed_insns = XEXP (postponed_insns, 1);
3435 free_INSN_LIST_node (tmp);
3437 if (! purge_addressof_1 (&PATTERN (insn), insn,
3438 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht))
3443 purge_bitfield_addressof_replacements = 0;
3444 purge_addressof_replacements = 0;
3446 /* REGs are shared. purge_addressof will destructively replace a REG
3447 with a MEM, which creates shared MEMs.
3449 Unfortunately, the children of put_reg_into_stack assume that MEMs
3450 referring to the same stack slot are shared (fixup_var_refs and
3451 the associated hash table code).
3453 So, we have to do another unsharing pass after we have flushed any
3454 REGs that had their address taken into the stack.
3456 It may be worth tracking whether or not we converted any REGs into
3457 MEMs to avoid this overhead when it is not needed. */
3458 unshare_all_rtl_again (get_insns ());
3461 /* Convert a SET of a hard subreg to a set of the appropriate hard
3462 register. A subroutine of purge_hard_subreg_sets. */
3465 purge_single_hard_subreg_set (rtx pattern)
3467 rtx reg = SET_DEST (pattern);
3468 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3471 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3472 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3474 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3475 GET_MODE (SUBREG_REG (reg)),
3478 reg = SUBREG_REG (reg);
3482 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3484 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3485 SET_DEST (pattern) = reg;
3489 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3490 only such SETs that we expect to see are those left in because
3491 integrate can't handle sets of parts of a return value register.
3493 We don't use alter_subreg because we only want to eliminate subregs
3494 of hard registers. */
3497 purge_hard_subreg_sets (rtx insn)
3499 for (; insn; insn = NEXT_INSN (insn))
3503 rtx pattern = PATTERN (insn);
3504 switch (GET_CODE (pattern))
3507 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3508 purge_single_hard_subreg_set (pattern);
3513 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3515 rtx inner_pattern = XVECEXP (pattern, 0, j);
3516 if (GET_CODE (inner_pattern) == SET
3517 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3518 purge_single_hard_subreg_set (inner_pattern);
3529 /* Pass through the INSNS of function FNDECL and convert virtual register
3530 references to hard register references. */
3533 instantiate_virtual_regs (tree fndecl, rtx insns)
3538 /* Compute the offsets to use for this function. */
3539 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3540 var_offset = STARTING_FRAME_OFFSET;
3541 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3542 out_arg_offset = STACK_POINTER_OFFSET;
3543 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3545 /* Scan all variables and parameters of this function. For each that is
3546 in memory, instantiate all virtual registers if the result is a valid
3547 address. If not, we do it later. That will handle most uses of virtual
3548 regs on many machines. */
3549 instantiate_decls (fndecl, 1);
3551 /* Initialize recognition, indicating that volatile is OK. */
3554 /* Scan through all the insns, instantiating every virtual register still
3556 for (insn = insns; insn; insn = NEXT_INSN (insn))
3557 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3558 || GET_CODE (insn) == CALL_INSN)
3560 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3561 if (INSN_DELETED_P (insn))
3563 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3564 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3565 if (GET_CODE (insn) == CALL_INSN)
3566 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3569 /* Past this point all ASM statements should match. Verify that
3570 to avoid failures later in the compilation process. */
3571 if (asm_noperands (PATTERN (insn)) >= 0
3572 && ! check_asm_operands (PATTERN (insn)))
3573 instantiate_virtual_regs_lossage (insn);
3576 /* Instantiate the stack slots for the parm registers, for later use in
3577 addressof elimination. */
3578 for (i = 0; i < max_parm_reg; ++i)
3579 if (parm_reg_stack_loc[i])
3580 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3582 /* Now instantiate the remaining register equivalences for debugging info.
3583 These will not be valid addresses. */
3584 instantiate_decls (fndecl, 0);
3586 /* Indicate that, from now on, assign_stack_local should use
3587 frame_pointer_rtx. */
3588 virtuals_instantiated = 1;
3591 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3592 all virtual registers in their DECL_RTL's.
3594 If VALID_ONLY, do this only if the resulting address is still valid.
3595 Otherwise, always do it. */
3598 instantiate_decls (tree fndecl, int valid_only)
3602 /* Process all parameters of the function. */
3603 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3605 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3606 HOST_WIDE_INT size_rtl;
3608 instantiate_decl (DECL_RTL (decl), size, valid_only);
3610 /* If the parameter was promoted, then the incoming RTL mode may be
3611 larger than the declared type size. We must use the larger of
3613 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3614 size = MAX (size_rtl, size);
3615 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3618 /* Now process all variables defined in the function or its subblocks. */
3619 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3622 /* Subroutine of instantiate_decls: Process all decls in the given
3623 BLOCK node and all its subblocks. */
3626 instantiate_decls_1 (tree let, int valid_only)
3630 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3631 if (DECL_RTL_SET_P (t))
3632 instantiate_decl (DECL_RTL (t),
3633 int_size_in_bytes (TREE_TYPE (t)),
3636 /* Process all subblocks. */
3637 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3638 instantiate_decls_1 (t, valid_only);
3641 /* Subroutine of the preceding procedures: Given RTL representing a
3642 decl and the size of the object, do any instantiation required.
3644 If VALID_ONLY is nonzero, it means that the RTL should only be
3645 changed if the new address is valid. */
3648 instantiate_decl (rtx x, HOST_WIDE_INT size, int valid_only)
3650 enum machine_mode mode;
3653 /* If this is not a MEM, no need to do anything. Similarly if the
3654 address is a constant or a register that is not a virtual register. */
3656 if (x == 0 || GET_CODE (x) != MEM)
3660 if (CONSTANT_P (addr)
3661 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3662 || (GET_CODE (addr) == REG
3663 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3664 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3667 /* If we should only do this if the address is valid, copy the address.
3668 We need to do this so we can undo any changes that might make the
3669 address invalid. This copy is unfortunate, but probably can't be
3673 addr = copy_rtx (addr);
3675 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3677 if (valid_only && size >= 0)
3679 unsigned HOST_WIDE_INT decl_size = size;
3681 /* Now verify that the resulting address is valid for every integer or
3682 floating-point mode up to and including SIZE bytes long. We do this
3683 since the object might be accessed in any mode and frame addresses
3686 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3687 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3688 mode = GET_MODE_WIDER_MODE (mode))
3689 if (! memory_address_p (mode, addr))
3692 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3693 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3694 mode = GET_MODE_WIDER_MODE (mode))
3695 if (! memory_address_p (mode, addr))
3699 /* Put back the address now that we have updated it and we either know
3700 it is valid or we don't care whether it is valid. */
3705 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3706 is a virtual register, return the equivalent hard register and set the
3707 offset indirectly through the pointer. Otherwise, return 0. */
3710 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
3713 HOST_WIDE_INT offset;
3715 if (x == virtual_incoming_args_rtx)
3716 new = arg_pointer_rtx, offset = in_arg_offset;
3717 else if (x == virtual_stack_vars_rtx)
3718 new = frame_pointer_rtx, offset = var_offset;
3719 else if (x == virtual_stack_dynamic_rtx)
3720 new = stack_pointer_rtx, offset = dynamic_offset;
3721 else if (x == virtual_outgoing_args_rtx)
3722 new = stack_pointer_rtx, offset = out_arg_offset;
3723 else if (x == virtual_cfa_rtx)
3724 new = arg_pointer_rtx, offset = cfa_offset;
3733 /* Called when instantiate_virtual_regs has failed to update the instruction.
3734 Usually this means that non-matching instruction has been emit, however for
3735 asm statements it may be the problem in the constraints. */
3737 instantiate_virtual_regs_lossage (rtx insn)
3739 if (asm_noperands (PATTERN (insn)) >= 0)
3741 error_for_asm (insn, "impossible constraint in `asm'");
3747 /* Given a pointer to a piece of rtx and an optional pointer to the
3748 containing object, instantiate any virtual registers present in it.
3750 If EXTRA_INSNS, we always do the replacement and generate
3751 any extra insns before OBJECT. If it zero, we do nothing if replacement
3754 Return 1 if we either had nothing to do or if we were able to do the
3755 needed replacement. Return 0 otherwise; we only return zero if
3756 EXTRA_INSNS is zero.
3758 We first try some simple transformations to avoid the creation of extra
3762 instantiate_virtual_regs_1 (rtx *loc, rtx object, int extra_insns)
3767 HOST_WIDE_INT offset = 0;
3773 /* Re-start here to avoid recursion in common cases. */
3780 /* We may have detected and deleted invalid asm statements. */
3781 if (object && INSN_P (object) && INSN_DELETED_P (object))
3784 code = GET_CODE (x);
3786 /* Check for some special cases. */
3804 /* We are allowed to set the virtual registers. This means that
3805 the actual register should receive the source minus the
3806 appropriate offset. This is used, for example, in the handling
3807 of non-local gotos. */
3808 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3810 rtx src = SET_SRC (x);
3812 /* We are setting the register, not using it, so the relevant
3813 offset is the negative of the offset to use were we using
3816 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3818 /* The only valid sources here are PLUS or REG. Just do
3819 the simplest possible thing to handle them. */
3820 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3822 instantiate_virtual_regs_lossage (object);
3827 if (GET_CODE (src) != REG)
3828 temp = force_operand (src, NULL_RTX);
3831 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3835 emit_insn_before (seq, object);
3838 if (! validate_change (object, &SET_SRC (x), temp, 0)
3840 instantiate_virtual_regs_lossage (object);
3845 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3850 /* Handle special case of virtual register plus constant. */
3851 if (CONSTANT_P (XEXP (x, 1)))
3853 rtx old, new_offset;
3855 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3856 if (GET_CODE (XEXP (x, 0)) == PLUS)
3858 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3860 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3862 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3871 #ifdef POINTERS_EXTEND_UNSIGNED
3872 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3873 we can commute the PLUS and SUBREG because pointers into the
3874 frame are well-behaved. */
3875 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3876 && GET_CODE (XEXP (x, 1)) == CONST_INT
3878 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3880 && validate_change (object, loc,
3881 plus_constant (gen_lowpart (ptr_mode,
3884 + INTVAL (XEXP (x, 1))),
3888 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3890 /* We know the second operand is a constant. Unless the
3891 first operand is a REG (which has been already checked),
3892 it needs to be checked. */
3893 if (GET_CODE (XEXP (x, 0)) != REG)
3901 new_offset = plus_constant (XEXP (x, 1), offset);
3903 /* If the new constant is zero, try to replace the sum with just
3905 if (new_offset == const0_rtx
3906 && validate_change (object, loc, new, 0))
3909 /* Next try to replace the register and new offset.
3910 There are two changes to validate here and we can't assume that
3911 in the case of old offset equals new just changing the register
3912 will yield a valid insn. In the interests of a little efficiency,
3913 however, we only call validate change once (we don't queue up the
3914 changes and then call apply_change_group). */
3918 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3919 : (XEXP (x, 0) = new,
3920 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3928 /* Otherwise copy the new constant into a register and replace
3929 constant with that register. */
3930 temp = gen_reg_rtx (Pmode);
3932 if (validate_change (object, &XEXP (x, 1), temp, 0))
3933 emit_insn_before (gen_move_insn (temp, new_offset), object);
3936 /* If that didn't work, replace this expression with a
3937 register containing the sum. */
3940 new = gen_rtx_PLUS (Pmode, new, new_offset);
3943 temp = force_operand (new, NULL_RTX);
3947 emit_insn_before (seq, object);
3948 if (! validate_change (object, loc, temp, 0)
3949 && ! validate_replace_rtx (x, temp, object))
3951 instantiate_virtual_regs_lossage (object);
3960 /* Fall through to generic two-operand expression case. */
3966 case DIV: case UDIV:
3967 case MOD: case UMOD:
3968 case AND: case IOR: case XOR:
3969 case ROTATERT: case ROTATE:
3970 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3972 case GE: case GT: case GEU: case GTU:
3973 case LE: case LT: case LEU: case LTU:
3974 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3975 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3980 /* Most cases of MEM that convert to valid addresses have already been
3981 handled by our scan of decls. The only special handling we
3982 need here is to make a copy of the rtx to ensure it isn't being
3983 shared if we have to change it to a pseudo.
3985 If the rtx is a simple reference to an address via a virtual register,
3986 it can potentially be shared. In such cases, first try to make it
3987 a valid address, which can also be shared. Otherwise, copy it and
3990 First check for common cases that need no processing. These are
3991 usually due to instantiation already being done on a previous instance
3995 if (CONSTANT_ADDRESS_P (temp)
3996 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3997 || temp == arg_pointer_rtx
3999 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4000 || temp == hard_frame_pointer_rtx
4002 || temp == frame_pointer_rtx)
4005 if (GET_CODE (temp) == PLUS
4006 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4007 && (XEXP (temp, 0) == frame_pointer_rtx
4008 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4009 || XEXP (temp, 0) == hard_frame_pointer_rtx
4011 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4012 || XEXP (temp, 0) == arg_pointer_rtx
4017 if (temp == virtual_stack_vars_rtx
4018 || temp == virtual_incoming_args_rtx
4019 || (GET_CODE (temp) == PLUS
4020 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4021 && (XEXP (temp, 0) == virtual_stack_vars_rtx
4022 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
4024 /* This MEM may be shared. If the substitution can be done without
4025 the need to generate new pseudos, we want to do it in place
4026 so all copies of the shared rtx benefit. The call below will
4027 only make substitutions if the resulting address is still
4030 Note that we cannot pass X as the object in the recursive call
4031 since the insn being processed may not allow all valid
4032 addresses. However, if we were not passed on object, we can
4033 only modify X without copying it if X will have a valid
4036 ??? Also note that this can still lose if OBJECT is an insn that
4037 has less restrictions on an address that some other insn.
4038 In that case, we will modify the shared address. This case
4039 doesn't seem very likely, though. One case where this could
4040 happen is in the case of a USE or CLOBBER reference, but we
4041 take care of that below. */
4043 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4044 object ? object : x, 0))
4047 /* Otherwise make a copy and process that copy. We copy the entire
4048 RTL expression since it might be a PLUS which could also be
4050 *loc = x = copy_rtx (x);
4053 /* Fall through to generic unary operation case. */
4056 case STRICT_LOW_PART:
4058 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4059 case SIGN_EXTEND: case ZERO_EXTEND:
4060 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4061 case FLOAT: case FIX:
4062 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4067 case POPCOUNT: case PARITY:
4068 /* These case either have just one operand or we know that we need not
4069 check the rest of the operands. */
4075 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4076 go ahead and make the invalid one, but do it to a copy. For a REG,
4077 just make the recursive call, since there's no chance of a problem. */
4079 if ((GET_CODE (XEXP (x, 0)) == MEM
4080 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4082 || (GET_CODE (XEXP (x, 0)) == REG
4083 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4086 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4091 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4092 in front of this insn and substitute the temporary. */
4093 if ((new = instantiate_new_reg (x, &offset)) != 0)
4095 temp = plus_constant (new, offset);
4096 if (!validate_change (object, loc, temp, 0))
4102 temp = force_operand (temp, NULL_RTX);
4106 emit_insn_before (seq, object);
4107 if (! validate_change (object, loc, temp, 0)
4108 && ! validate_replace_rtx (x, temp, object))
4109 instantiate_virtual_regs_lossage (object);
4116 if (GET_CODE (XEXP (x, 0)) == REG)
4119 else if (GET_CODE (XEXP (x, 0)) == MEM)
4121 /* If we have a (addressof (mem ..)), do any instantiation inside
4122 since we know we'll be making the inside valid when we finally
4123 remove the ADDRESSOF. */
4124 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4133 /* Scan all subexpressions. */
4134 fmt = GET_RTX_FORMAT (code);
4135 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4138 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4141 else if (*fmt == 'E')
4142 for (j = 0; j < XVECLEN (x, i); j++)
4143 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4150 /* Return the first insn following those generated by `assign_parms'. */
4153 get_first_nonparm_insn (void)
4156 return NEXT_INSN (last_parm_insn);
4157 return get_insns ();
4160 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4161 This means a type for which function calls must pass an address to the
4162 function or get an address back from the function.
4163 EXP may be a type node or an expression (whose type is tested). */
4166 aggregate_value_p (tree exp, tree fntype)
4168 int i, regno, nregs;
4171 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4174 switch (TREE_CODE (fntype))
4177 fntype = get_callee_fndecl (fntype);
4178 fntype = fntype ? TREE_TYPE (fntype) : 0;
4181 fntype = TREE_TYPE (fntype);
4186 case IDENTIFIER_NODE:
4190 /* We don't expect other rtl types here. */
4194 if (TREE_CODE (type) == VOID_TYPE)
4196 if (targetm.calls.return_in_memory (type, fntype))
4198 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4199 and thus can't be returned in registers. */
4200 if (TREE_ADDRESSABLE (type))
4202 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4204 /* Make sure we have suitable call-clobbered regs to return
4205 the value in; if not, we must return it in memory. */
4206 reg = hard_function_value (type, 0, 0);
4208 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4210 if (GET_CODE (reg) != REG)
4213 regno = REGNO (reg);
4214 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
4215 for (i = 0; i < nregs; i++)
4216 if (! call_used_regs[regno + i])
4221 /* Assign RTL expressions to the function's parameters.
4222 This may involve copying them into registers and using
4223 those registers as the RTL for them. */
4226 assign_parms (tree fndecl)
4229 CUMULATIVE_ARGS args_so_far;
4230 /* Total space needed so far for args on the stack,
4231 given as a constant and a tree-expression. */
4232 struct args_size stack_args_size;
4233 HOST_WIDE_INT extra_pretend_bytes = 0;
4234 tree fntype = TREE_TYPE (fndecl);
4235 tree fnargs = DECL_ARGUMENTS (fndecl), orig_fnargs;
4236 /* This is used for the arg pointer when referring to stack args. */
4237 rtx internal_arg_pointer;
4238 /* This is a dummy PARM_DECL that we used for the function result if
4239 the function returns a structure. */
4240 tree function_result_decl = 0;
4241 int varargs_setup = 0;
4242 int reg_parm_stack_space ATTRIBUTE_UNUSED = 0;
4243 rtx conversion_insns = 0;
4245 /* Nonzero if function takes extra anonymous args.
4246 This means the last named arg must be on the stack
4247 right before the anonymous ones. */
4248 int stdarg = current_function_stdarg;
4250 /* If the reg that the virtual arg pointer will be translated into is
4251 not a fixed reg or is the stack pointer, make a copy of the virtual
4252 arg pointer, and address parms via the copy. The frame pointer is
4253 considered fixed even though it is not marked as such.
4255 The second time through, simply use ap to avoid generating rtx. */
4257 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4258 || ! (fixed_regs[ARG_POINTER_REGNUM]
4259 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4260 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4262 internal_arg_pointer = virtual_incoming_args_rtx;
4263 current_function_internal_arg_pointer = internal_arg_pointer;
4265 stack_args_size.constant = 0;
4266 stack_args_size.var = 0;
4268 /* If struct value address is treated as the first argument, make it so. */
4269 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
4270 && ! current_function_returns_pcc_struct
4271 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
4273 tree type = build_pointer_type (TREE_TYPE (fntype));
4275 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4277 DECL_ARG_TYPE (function_result_decl) = type;
4278 TREE_CHAIN (function_result_decl) = fnargs;
4279 fnargs = function_result_decl;
4282 orig_fnargs = fnargs;
4284 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4285 parm_reg_stack_loc = ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4287 /* If the target wants to split complex arguments into scalars, do so. */
4288 if (targetm.calls.split_complex_arg)
4289 fnargs = split_complex_args (fnargs);
4291 #ifdef REG_PARM_STACK_SPACE
4292 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4295 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4296 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4298 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl, -1);
4301 /* We haven't yet found an argument that we must push and pretend the
4303 current_function_pretend_args_size = 0;
4305 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4309 enum machine_mode promoted_mode, passed_mode;
4310 enum machine_mode nominal_mode, promoted_nominal_mode;
4312 struct locate_and_pad_arg_data locate;
4313 int passed_pointer = 0;
4314 int did_conversion = 0;
4315 tree passed_type = DECL_ARG_TYPE (parm);
4316 tree nominal_type = TREE_TYPE (parm);
4317 int last_named = 0, named_arg;
4320 int pretend_bytes = 0;
4321 int loaded_in_reg = 0;
4323 /* Set LAST_NAMED if this is last named arg before last
4329 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4330 if (DECL_NAME (tem))
4336 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4337 most machines, if this is a varargs/stdarg function, then we treat
4338 the last named arg as if it were anonymous too. */
4339 named_arg = (targetm.calls.strict_argument_naming (&args_so_far)
4342 if (TREE_TYPE (parm) == error_mark_node
4343 /* This can happen after weird syntax errors
4344 or if an enum type is defined among the parms. */
4345 || TREE_CODE (parm) != PARM_DECL
4346 || passed_type == NULL)
4348 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4349 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4350 TREE_USED (parm) = 1;
4354 /* Find mode of arg as it is passed, and mode of arg
4355 as it should be during execution of this function. */
4356 passed_mode = TYPE_MODE (passed_type);
4357 nominal_mode = TYPE_MODE (nominal_type);
4359 /* If the parm's mode is VOID, its value doesn't matter,
4360 and avoid the usual things like emit_move_insn that could crash. */
4361 if (nominal_mode == VOIDmode)
4363 SET_DECL_RTL (parm, const0_rtx);
4364 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4368 /* If the parm is to be passed as a transparent union, use the
4369 type of the first field for the tests below. We have already
4370 verified that the modes are the same. */
4371 if (DECL_TRANSPARENT_UNION (parm)
4372 || (TREE_CODE (passed_type) == UNION_TYPE
4373 && TYPE_TRANSPARENT_UNION (passed_type)))
4374 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4376 /* See if this arg was passed by invisible reference. It is if
4377 it is an object whose size depends on the contents of the
4378 object itself or if the machine requires these objects be passed
4381 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type))
4382 || TREE_ADDRESSABLE (passed_type)
4383 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4384 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4385 passed_type, named_arg)
4389 passed_type = nominal_type = build_pointer_type (passed_type);
4391 passed_mode = nominal_mode = Pmode;
4393 /* See if the frontend wants to pass this by invisible reference. */
4394 else if (passed_type != nominal_type
4395 && POINTER_TYPE_P (passed_type)
4396 && TREE_TYPE (passed_type) == nominal_type)
4398 nominal_type = passed_type;
4400 passed_mode = nominal_mode = Pmode;
4403 promoted_mode = passed_mode;
4405 if (targetm.calls.promote_function_args (TREE_TYPE (fndecl)))
4407 /* Compute the mode in which the arg is actually extended to. */
4408 unsignedp = TYPE_UNSIGNED (passed_type);
4409 promoted_mode = promote_mode (passed_type, promoted_mode,
4413 /* Let machine desc say which reg (if any) the parm arrives in.
4414 0 means it arrives on the stack. */
4415 #ifdef FUNCTION_INCOMING_ARG
4416 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4417 passed_type, named_arg);
4419 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4420 passed_type, named_arg);
4423 if (entry_parm == 0)
4424 promoted_mode = passed_mode;
4426 /* If this is the last named parameter, do any required setup for
4427 varargs or stdargs. We need to know about the case of this being an
4428 addressable type, in which case we skip the registers it
4429 would have arrived in.
4431 For stdargs, LAST_NAMED will be set for two parameters, the one that
4432 is actually the last named, and the dummy parameter. We only
4433 want to do this action once.
4435 Also, indicate when RTL generation is to be suppressed. */
4436 if (last_named && !varargs_setup)
4438 int varargs_pretend_bytes = 0;
4439 targetm.calls.setup_incoming_varargs (&args_so_far, promoted_mode,
4441 &varargs_pretend_bytes, 0);
4444 /* If the back-end has requested extra stack space, record how
4445 much is needed. Do not change pretend_args_size otherwise
4446 since it may be nonzero from an earlier partial argument. */
4447 if (varargs_pretend_bytes > 0)
4448 current_function_pretend_args_size = varargs_pretend_bytes;
4451 /* Determine parm's home in the stack,
4452 in case it arrives in the stack or we should pretend it did.
4454 Compute the stack position and rtx where the argument arrives
4457 There is one complexity here: If this was a parameter that would
4458 have been passed in registers, but wasn't only because it is
4459 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4460 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4461 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4462 0 as it was the previous time. */
4463 in_regs = entry_parm != 0;
4464 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4467 if (!in_regs && !named_arg)
4470 targetm.calls.pretend_outgoing_varargs_named (&args_so_far);
4473 #ifdef FUNCTION_INCOMING_ARG
4474 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4476 pretend_named) != 0;
4478 in_regs = FUNCTION_ARG (args_so_far, promoted_mode,
4480 pretend_named) != 0;
4485 /* If this parameter was passed both in registers and in the stack,
4486 use the copy on the stack. */
4487 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4490 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4493 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4494 passed_type, named_arg);
4496 /* The caller might already have allocated stack space
4497 for the register parameters. */
4498 && reg_parm_stack_space == 0)
4500 /* Part of this argument is passed in registers and part
4501 is passed on the stack. Ask the prologue code to extend
4502 the stack part so that we can recreate the full value.
4504 PRETEND_BYTES is the size of the registers we need to store.
4505 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
4506 stack space that the prologue should allocate.
4508 Internally, gcc assumes that the argument pointer is
4509 aligned to STACK_BOUNDARY bits. This is used both for
4510 alignment optimizations (see init_emit) and to locate
4511 arguments that are aligned to more than PARM_BOUNDARY
4512 bits. We must preserve this invariant by rounding
4513 CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to a stack
4516 /* We assume at most one partial arg, and it must be the first
4517 argument on the stack. */
4518 if (extra_pretend_bytes || current_function_pretend_args_size)
4521 pretend_bytes = partial * UNITS_PER_WORD;
4522 current_function_pretend_args_size
4523 = CEIL_ROUND (pretend_bytes, STACK_BYTES);
4525 /* We want to align relative to the actual stack pointer, so
4526 don't include this in the stack size until later. */
4527 extra_pretend_bytes = current_function_pretend_args_size;
4532 memset (&locate, 0, sizeof (locate));
4533 locate_and_pad_parm (promoted_mode, passed_type, in_regs,
4534 entry_parm ? partial : 0, fndecl,
4535 &stack_args_size, &locate);
4536 /* Adjust offsets to include the pretend args. */
4537 locate.slot_offset.constant += extra_pretend_bytes - pretend_bytes;
4538 locate.offset.constant += extra_pretend_bytes - pretend_bytes;
4543 /* If we're passing this arg using a reg, make its stack home
4544 the aligned stack slot. */
4546 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset);
4548 offset_rtx = ARGS_SIZE_RTX (locate.offset);
4550 if (offset_rtx == const0_rtx)
4551 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4553 stack_parm = gen_rtx_MEM (promoted_mode,
4554 gen_rtx_PLUS (Pmode,
4555 internal_arg_pointer,
4558 set_mem_attributes (stack_parm, parm, 1);
4559 if (entry_parm && MEM_ATTRS (stack_parm)->align < PARM_BOUNDARY)
4560 set_mem_align (stack_parm, PARM_BOUNDARY);
4562 /* Set also REG_ATTRS if parameter was passed in a register. */
4564 set_reg_attrs_for_parm (entry_parm, stack_parm);
4567 /* If this parm was passed part in regs and part in memory,
4568 pretend it arrived entirely in memory
4569 by pushing the register-part onto the stack.
4571 In the special case of a DImode or DFmode that is split,
4572 we could put it together in a pseudoreg directly,
4573 but for now that's not worth bothering with. */
4577 /* Handle calls that pass values in multiple non-contiguous
4578 locations. The Irix 6 ABI has examples of this. */
4579 if (GET_CODE (entry_parm) == PARALLEL)
4580 emit_group_store (validize_mem (stack_parm), entry_parm,
4582 int_size_in_bytes (TREE_TYPE (parm)));
4585 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
4588 entry_parm = stack_parm;
4591 /* If we didn't decide this parm came in a register,
4592 by default it came on the stack. */
4593 if (entry_parm == 0)
4594 entry_parm = stack_parm;
4596 /* Record permanently how this parm was passed. */
4597 set_decl_incoming_rtl (parm, entry_parm);
4599 /* If there is actually space on the stack for this parm,
4600 count it in stack_args_size; otherwise set stack_parm to 0
4601 to indicate there is no preallocated stack slot for the parm. */
4603 if (entry_parm == stack_parm
4604 || (GET_CODE (entry_parm) == PARALLEL
4605 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4606 #if defined (REG_PARM_STACK_SPACE)
4607 /* On some machines, even if a parm value arrives in a register
4608 there is still an (uninitialized) stack slot allocated
4610 || REG_PARM_STACK_SPACE (fndecl) > 0
4614 stack_args_size.constant += locate.size.constant;
4615 if (locate.size.var)
4616 ADD_PARM_SIZE (stack_args_size, locate.size.var);
4619 /* No stack slot was pushed for this parm. */
4622 /* Update info on where next arg arrives in registers. */
4624 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4625 passed_type, named_arg);
4627 /* If we can't trust the parm stack slot to be aligned enough
4628 for its ultimate type, don't use that slot after entry.
4629 We'll make another stack slot, if we need one. */
4631 unsigned int thisparm_boundary
4632 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4634 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4638 /* If parm was passed in memory, and we need to convert it on entry,
4639 don't store it back in that same slot. */
4640 if (entry_parm == stack_parm
4641 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4644 /* When an argument is passed in multiple locations, we can't
4645 make use of this information, but we can save some copying if
4646 the whole argument is passed in a single register. */
4647 if (GET_CODE (entry_parm) == PARALLEL
4648 && nominal_mode != BLKmode && passed_mode != BLKmode)
4650 int i, len = XVECLEN (entry_parm, 0);
4652 for (i = 0; i < len; i++)
4653 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4654 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4655 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4657 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4659 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4660 set_decl_incoming_rtl (parm, entry_parm);
4665 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4666 in the mode in which it arrives.
4667 STACK_PARM is an RTX for a stack slot where the parameter can live
4668 during the function (in case we want to put it there).
4669 STACK_PARM is 0 if no stack slot was pushed for it.
4671 Now output code if necessary to convert ENTRY_PARM to
4672 the type in which this function declares it,
4673 and store that result in an appropriate place,
4674 which may be a pseudo reg, may be STACK_PARM,
4675 or may be a local stack slot if STACK_PARM is 0.
4677 Set DECL_RTL to that place. */
4679 if (GET_CODE (entry_parm) == PARALLEL && nominal_mode != BLKmode
4680 && XVECLEN (entry_parm, 0) > 1)
4682 /* Reconstitute objects the size of a register or larger using
4683 register operations instead of the stack. */
4684 rtx parmreg = gen_reg_rtx (nominal_mode);
4686 if (REG_P (parmreg))
4688 unsigned int regno = REGNO (parmreg);
4690 emit_group_store (parmreg, entry_parm, TREE_TYPE (parm),
4691 int_size_in_bytes (TREE_TYPE (parm)));
4692 SET_DECL_RTL (parm, parmreg);
4695 if (regno >= max_parm_reg)
4698 int old_max_parm_reg = max_parm_reg;
4700 /* It's slow to expand this one register at a time,
4701 but it's also rare and we need max_parm_reg to be
4702 precisely correct. */
4703 max_parm_reg = regno + 1;
4704 new = ggc_realloc (parm_reg_stack_loc,
4705 max_parm_reg * sizeof (rtx));
4706 memset (new + old_max_parm_reg, 0,
4707 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4708 parm_reg_stack_loc = new;
4709 parm_reg_stack_loc[regno] = stack_parm;
4714 if (nominal_mode == BLKmode
4715 #ifdef BLOCK_REG_PADDING
4716 || (locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward)
4717 && GET_MODE_SIZE (promoted_mode) < UNITS_PER_WORD)
4719 || GET_CODE (entry_parm) == PARALLEL)
4721 /* If a BLKmode arrives in registers, copy it to a stack slot.
4722 Handle calls that pass values in multiple non-contiguous
4723 locations. The Irix 6 ABI has examples of this. */
4724 if (GET_CODE (entry_parm) == REG
4725 || (GET_CODE (entry_parm) == PARALLEL
4726 && (!loaded_in_reg || !optimize)))
4728 int size = int_size_in_bytes (TREE_TYPE (parm));
4729 int size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
4732 /* Note that we will be storing an integral number of words.
4733 So we have to be careful to ensure that we allocate an
4734 integral number of words. We do this below in the
4735 assign_stack_local if space was not allocated in the argument
4736 list. If it was, this will not work if PARM_BOUNDARY is not
4737 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4738 if it becomes a problem. Exception is when BLKmode arrives
4739 with arguments not conforming to word_mode. */
4741 if (stack_parm == 0)
4743 stack_parm = assign_stack_local (BLKmode, size_stored, 0);
4744 PUT_MODE (stack_parm, GET_MODE (entry_parm));
4745 set_mem_attributes (stack_parm, parm, 1);
4747 else if (GET_CODE (entry_parm) == PARALLEL
4748 && GET_MODE(entry_parm) == BLKmode)
4750 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4753 mem = validize_mem (stack_parm);
4755 /* Handle calls that pass values in multiple non-contiguous
4756 locations. The Irix 6 ABI has examples of this. */
4757 if (GET_CODE (entry_parm) == PARALLEL)
4758 emit_group_store (mem, entry_parm, TREE_TYPE (parm), size);
4763 /* If SIZE is that of a mode no bigger than a word, just use
4764 that mode's store operation. */
4765 else if (size <= UNITS_PER_WORD)
4767 enum machine_mode mode
4768 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
4771 #ifdef BLOCK_REG_PADDING
4772 && (size == UNITS_PER_WORD
4773 || (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4774 != (BYTES_BIG_ENDIAN ? upward : downward)))
4778 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
4779 emit_move_insn (change_address (mem, mode, 0), reg);
4782 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
4783 machine must be aligned to the left before storing
4784 to memory. Note that the previous test doesn't
4785 handle all cases (e.g. SIZE == 3). */
4786 else if (size != UNITS_PER_WORD
4787 #ifdef BLOCK_REG_PADDING
4788 && (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4796 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4797 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
4799 x = expand_binop (word_mode, ashl_optab, reg,
4800 GEN_INT (by), 0, 1, OPTAB_WIDEN);
4801 tem = change_address (mem, word_mode, 0);
4802 emit_move_insn (tem, x);
4805 move_block_from_reg (REGNO (entry_parm), mem,
4806 size_stored / UNITS_PER_WORD);
4809 move_block_from_reg (REGNO (entry_parm), mem,
4810 size_stored / UNITS_PER_WORD);
4812 /* If parm is already bound to register pair, don't change
4814 if (! DECL_RTL_SET_P (parm))
4815 SET_DECL_RTL (parm, stack_parm);
4817 else if (! ((! optimize
4818 && ! DECL_REGISTER (parm))
4819 || TREE_SIDE_EFFECTS (parm)
4820 /* If -ffloat-store specified, don't put explicit
4821 float variables into registers. */
4822 || (flag_float_store
4823 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4824 /* Always assign pseudo to structure return or item passed
4825 by invisible reference. */
4826 || passed_pointer || parm == function_result_decl)
4828 /* Store the parm in a pseudoregister during the function, but we
4829 may need to do it in a wider mode. */
4832 unsigned int regno, regnoi = 0, regnor = 0;
4834 unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
4836 promoted_nominal_mode
4837 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4839 parmreg = gen_reg_rtx (promoted_nominal_mode);
4840 mark_user_reg (parmreg);
4842 /* If this was an item that we received a pointer to, set DECL_RTL
4846 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4848 set_mem_attributes (x, parm, 1);
4849 SET_DECL_RTL (parm, x);
4853 SET_DECL_RTL (parm, parmreg);
4854 maybe_set_unchanging (DECL_RTL (parm), parm);
4857 /* Copy the value into the register. */
4858 if (nominal_mode != passed_mode
4859 || promoted_nominal_mode != promoted_mode)
4862 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4863 mode, by the caller. We now have to convert it to
4864 NOMINAL_MODE, if different. However, PARMREG may be in
4865 a different mode than NOMINAL_MODE if it is being stored
4868 If ENTRY_PARM is a hard register, it might be in a register
4869 not valid for operating in its mode (e.g., an odd-numbered
4870 register for a DFmode). In that case, moves are the only
4871 thing valid, so we can't do a convert from there. This
4872 occurs when the calling sequence allow such misaligned
4875 In addition, the conversion may involve a call, which could
4876 clobber parameters which haven't been copied to pseudo
4877 registers yet. Therefore, we must first copy the parm to
4878 a pseudo reg here, and save the conversion until after all
4879 parameters have been moved. */
4881 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4883 emit_move_insn (tempreg, validize_mem (entry_parm));
4885 push_to_sequence (conversion_insns);
4886 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4888 if (GET_CODE (tempreg) == SUBREG
4889 && GET_MODE (tempreg) == nominal_mode
4890 && GET_CODE (SUBREG_REG (tempreg)) == REG
4891 && nominal_mode == passed_mode
4892 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4893 && GET_MODE_SIZE (GET_MODE (tempreg))
4894 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4896 /* The argument is already sign/zero extended, so note it
4898 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4899 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4902 /* TREE_USED gets set erroneously during expand_assignment. */
4903 save_tree_used = TREE_USED (parm);
4904 expand_assignment (parm,
4905 make_tree (nominal_type, tempreg), 0);
4906 TREE_USED (parm) = save_tree_used;
4907 conversion_insns = get_insns ();
4912 emit_move_insn (parmreg, validize_mem (entry_parm));
4914 /* If we were passed a pointer but the actual value
4915 can safely live in a register, put it in one. */
4916 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4917 /* If by-reference argument was promoted, demote it. */
4918 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4920 && ! DECL_REGISTER (parm))
4921 || TREE_SIDE_EFFECTS (parm)
4922 /* If -ffloat-store specified, don't put explicit
4923 float variables into registers. */
4924 || (flag_float_store
4925 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4927 /* We can't use nominal_mode, because it will have been set to
4928 Pmode above. We must use the actual mode of the parm. */
4929 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4930 mark_user_reg (parmreg);
4931 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4933 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4934 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
4935 push_to_sequence (conversion_insns);
4936 emit_move_insn (tempreg, DECL_RTL (parm));
4938 convert_to_mode (GET_MODE (parmreg),
4941 emit_move_insn (parmreg, DECL_RTL (parm));
4942 conversion_insns = get_insns();
4947 emit_move_insn (parmreg, DECL_RTL (parm));
4948 SET_DECL_RTL (parm, parmreg);
4949 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4953 #ifdef FUNCTION_ARG_CALLEE_COPIES
4954 /* If we are passed an arg by reference and it is our responsibility
4955 to make a copy, do it now.
4956 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4957 original argument, so we must recreate them in the call to
4958 FUNCTION_ARG_CALLEE_COPIES. */
4959 /* ??? Later add code to handle the case that if the argument isn't
4960 modified, don't do the copy. */
4962 else if (passed_pointer
4963 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4964 TYPE_MODE (TREE_TYPE (passed_type)),
4965 TREE_TYPE (passed_type),
4967 && ! TREE_ADDRESSABLE (TREE_TYPE (passed_type)))
4970 tree type = TREE_TYPE (passed_type);
4972 /* This sequence may involve a library call perhaps clobbering
4973 registers that haven't been copied to pseudos yet. */
4975 push_to_sequence (conversion_insns);
4977 if (!COMPLETE_TYPE_P (type)
4978 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4979 /* This is a variable sized object. */
4980 copy = gen_rtx_MEM (BLKmode,
4981 allocate_dynamic_stack_space
4982 (expr_size (parm), NULL_RTX,
4983 TYPE_ALIGN (type)));
4985 copy = assign_stack_temp (TYPE_MODE (type),
4986 int_size_in_bytes (type), 1);
4987 set_mem_attributes (copy, parm, 1);
4989 store_expr (parm, copy, 0);
4990 emit_move_insn (parmreg, XEXP (copy, 0));
4991 conversion_insns = get_insns ();
4995 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4997 /* In any case, record the parm's desired stack location
4998 in case we later discover it must live in the stack.
5000 If it is a COMPLEX value, store the stack location for both
5003 if (GET_CODE (parmreg) == CONCAT)
5004 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
5006 regno = REGNO (parmreg);
5008 if (regno >= max_parm_reg)
5011 int old_max_parm_reg = max_parm_reg;
5013 /* It's slow to expand this one register at a time,
5014 but it's also rare and we need max_parm_reg to be
5015 precisely correct. */
5016 max_parm_reg = regno + 1;
5017 new = ggc_realloc (parm_reg_stack_loc,
5018 max_parm_reg * sizeof (rtx));
5019 memset (new + old_max_parm_reg, 0,
5020 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
5021 parm_reg_stack_loc = new;
5024 if (GET_CODE (parmreg) == CONCAT)
5026 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
5028 regnor = REGNO (gen_realpart (submode, parmreg));
5029 regnoi = REGNO (gen_imagpart (submode, parmreg));
5031 if (stack_parm != 0)
5033 parm_reg_stack_loc[regnor]
5034 = gen_realpart (submode, stack_parm);
5035 parm_reg_stack_loc[regnoi]
5036 = gen_imagpart (submode, stack_parm);
5040 parm_reg_stack_loc[regnor] = 0;
5041 parm_reg_stack_loc[regnoi] = 0;
5045 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
5047 /* Mark the register as eliminable if we did no conversion
5048 and it was copied from memory at a fixed offset,
5049 and the arg pointer was not copied to a pseudo-reg.
5050 If the arg pointer is a pseudo reg or the offset formed
5051 an invalid address, such memory-equivalences
5052 as we make here would screw up life analysis for it. */
5053 if (nominal_mode == passed_mode
5056 && GET_CODE (stack_parm) == MEM
5057 && locate.offset.var == 0
5058 && reg_mentioned_p (virtual_incoming_args_rtx,
5059 XEXP (stack_parm, 0)))
5061 rtx linsn = get_last_insn ();
5064 /* Mark complex types separately. */
5065 if (GET_CODE (parmreg) == CONCAT)
5066 /* Scan backwards for the set of the real and
5068 for (sinsn = linsn; sinsn != 0;
5069 sinsn = prev_nonnote_insn (sinsn))
5071 set = single_set (sinsn);
5073 && SET_DEST (set) == regno_reg_rtx [regnoi])
5075 = gen_rtx_EXPR_LIST (REG_EQUIV,
5076 parm_reg_stack_loc[regnoi],
5079 && SET_DEST (set) == regno_reg_rtx [regnor])
5081 = gen_rtx_EXPR_LIST (REG_EQUIV,
5082 parm_reg_stack_loc[regnor],
5085 else if ((set = single_set (linsn)) != 0
5086 && SET_DEST (set) == parmreg)
5088 = gen_rtx_EXPR_LIST (REG_EQUIV,
5089 stack_parm, REG_NOTES (linsn));
5092 /* For pointer data type, suggest pointer register. */
5093 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5094 mark_reg_pointer (parmreg,
5095 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5097 /* If something wants our address, try to use ADDRESSOF. */
5098 if (TREE_ADDRESSABLE (parm))
5100 /* If we end up putting something into the stack,
5101 fixup_var_refs_insns will need to make a pass over
5102 all the instructions. It looks through the pending
5103 sequences -- but it can't see the ones in the
5104 CONVERSION_INSNS, if they're not on the sequence
5105 stack. So, we go back to that sequence, just so that
5106 the fixups will happen. */
5107 push_to_sequence (conversion_insns);
5108 put_var_into_stack (parm, /*rescan=*/true);
5109 conversion_insns = get_insns ();
5115 /* Value must be stored in the stack slot STACK_PARM
5116 during function execution. */
5118 if (promoted_mode != nominal_mode)
5120 /* Conversion is required. */
5121 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5123 emit_move_insn (tempreg, validize_mem (entry_parm));
5125 push_to_sequence (conversion_insns);
5126 entry_parm = convert_to_mode (nominal_mode, tempreg,
5127 TYPE_UNSIGNED (TREE_TYPE (parm)));
5129 /* ??? This may need a big-endian conversion on sparc64. */
5130 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5132 conversion_insns = get_insns ();
5137 if (entry_parm != stack_parm)
5139 if (stack_parm == 0)
5142 = assign_stack_local (GET_MODE (entry_parm),
5143 GET_MODE_SIZE (GET_MODE (entry_parm)),
5145 set_mem_attributes (stack_parm, parm, 1);
5148 if (promoted_mode != nominal_mode)
5150 push_to_sequence (conversion_insns);
5151 emit_move_insn (validize_mem (stack_parm),
5152 validize_mem (entry_parm));
5153 conversion_insns = get_insns ();
5157 emit_move_insn (validize_mem (stack_parm),
5158 validize_mem (entry_parm));
5161 SET_DECL_RTL (parm, stack_parm);
5165 if (targetm.calls.split_complex_arg && fnargs != orig_fnargs)
5167 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
5169 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
5170 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
5172 rtx tmp, real, imag;
5173 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
5175 real = DECL_RTL (fnargs);
5176 imag = DECL_RTL (TREE_CHAIN (fnargs));
5177 if (inner != GET_MODE (real))
5179 real = gen_lowpart_SUBREG (inner, real);
5180 imag = gen_lowpart_SUBREG (inner, imag);
5182 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
5183 SET_DECL_RTL (parm, tmp);
5185 real = DECL_INCOMING_RTL (fnargs);
5186 imag = DECL_INCOMING_RTL (TREE_CHAIN (fnargs));
5187 if (inner != GET_MODE (real))
5189 real = gen_lowpart_SUBREG (inner, real);
5190 imag = gen_lowpart_SUBREG (inner, imag);
5192 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
5193 set_decl_incoming_rtl (parm, tmp);
5194 fnargs = TREE_CHAIN (fnargs);
5198 SET_DECL_RTL (parm, DECL_RTL (fnargs));
5199 set_decl_incoming_rtl (parm, DECL_INCOMING_RTL (fnargs));
5201 /* Set MEM_EXPR to the original decl, i.e. to PARM,
5202 instead of the copy of decl, i.e. FNARGS. */
5203 if (DECL_INCOMING_RTL (parm)
5204 && GET_CODE (DECL_INCOMING_RTL (parm)) == MEM)
5205 set_mem_expr (DECL_INCOMING_RTL (parm), parm);
5207 fnargs = TREE_CHAIN (fnargs);
5211 /* Output all parameter conversion instructions (possibly including calls)
5212 now that all parameters have been copied out of hard registers. */
5213 emit_insn (conversion_insns);
5215 /* If we are receiving a struct value address as the first argument, set up
5216 the RTL for the function result. As this might require code to convert
5217 the transmitted address to Pmode, we do this here to ensure that possible
5218 preliminary conversions of the address have been emitted already. */
5219 if (function_result_decl)
5221 tree result = DECL_RESULT (fndecl);
5222 rtx addr = DECL_RTL (function_result_decl);
5225 addr = convert_memory_address (Pmode, addr);
5226 x = gen_rtx_MEM (DECL_MODE (result), addr);
5227 set_mem_attributes (x, result, 1);
5228 SET_DECL_RTL (result, x);
5231 last_parm_insn = get_last_insn ();
5233 /* We have aligned all the args, so add space for the pretend args. */
5234 stack_args_size.constant += extra_pretend_bytes;
5235 current_function_args_size = stack_args_size.constant;
5237 /* Adjust function incoming argument size for alignment and
5240 #ifdef REG_PARM_STACK_SPACE
5241 current_function_args_size = MAX (current_function_args_size,
5242 REG_PARM_STACK_SPACE (fndecl));
5245 current_function_args_size
5246 = ((current_function_args_size + STACK_BYTES - 1)
5247 / STACK_BYTES) * STACK_BYTES;
5249 #ifdef ARGS_GROW_DOWNWARD
5250 current_function_arg_offset_rtx
5251 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5252 : expand_expr (size_diffop (stack_args_size.var,
5253 size_int (-stack_args_size.constant)),
5254 NULL_RTX, VOIDmode, 0));
5256 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5259 /* See how many bytes, if any, of its args a function should try to pop
5262 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5263 current_function_args_size);
5265 /* For stdarg.h function, save info about
5266 regs and stack space used by the named args. */
5268 current_function_args_info = args_so_far;
5270 /* Set the rtx used for the function return value. Put this in its
5271 own variable so any optimizers that need this information don't have
5272 to include tree.h. Do this here so it gets done when an inlined
5273 function gets output. */
5275 current_function_return_rtx
5276 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5277 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5279 /* If scalar return value was computed in a pseudo-reg, or was a named
5280 return value that got dumped to the stack, copy that to the hard
5282 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5284 tree decl_result = DECL_RESULT (fndecl);
5285 rtx decl_rtl = DECL_RTL (decl_result);
5287 if (REG_P (decl_rtl)
5288 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5289 : DECL_REGISTER (decl_result))
5293 #ifdef FUNCTION_OUTGOING_VALUE
5294 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5297 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5300 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5301 /* The delay slot scheduler assumes that current_function_return_rtx
5302 holds the hard register containing the return value, not a
5303 temporary pseudo. */
5304 current_function_return_rtx = real_decl_rtl;
5309 /* If ARGS contains entries with complex types, split the entry into two
5310 entries of the component type. Return a new list of substitutions are
5311 needed, else the old list. */
5314 split_complex_args (tree args)
5318 /* Before allocating memory, check for the common case of no complex. */
5319 for (p = args; p; p = TREE_CHAIN (p))
5321 tree type = TREE_TYPE (p);
5322 if (TREE_CODE (type) == COMPLEX_TYPE
5323 && targetm.calls.split_complex_arg (type))
5329 args = copy_list (args);
5331 for (p = args; p; p = TREE_CHAIN (p))
5333 tree type = TREE_TYPE (p);
5334 if (TREE_CODE (type) == COMPLEX_TYPE
5335 && targetm.calls.split_complex_arg (type))
5338 tree subtype = TREE_TYPE (type);
5340 /* Rewrite the PARM_DECL's type with its component. */
5341 TREE_TYPE (p) = subtype;
5342 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
5343 DECL_MODE (p) = VOIDmode;
5344 DECL_SIZE (p) = NULL;
5345 DECL_SIZE_UNIT (p) = NULL;
5348 /* Build a second synthetic decl. */
5349 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
5350 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
5351 layout_decl (decl, 0);
5353 /* Splice it in; skip the new decl. */
5354 TREE_CHAIN (decl) = TREE_CHAIN (p);
5355 TREE_CHAIN (p) = decl;
5363 /* Indicate whether REGNO is an incoming argument to the current function
5364 that was promoted to a wider mode. If so, return the RTX for the
5365 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5366 that REGNO is promoted from and whether the promotion was signed or
5370 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
5374 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5375 arg = TREE_CHAIN (arg))
5376 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5377 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5378 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5380 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5381 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (arg));
5383 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5384 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5385 && mode != DECL_MODE (arg))
5387 *pmode = DECL_MODE (arg);
5388 *punsignedp = unsignedp;
5389 return DECL_INCOMING_RTL (arg);
5397 /* Compute the size and offset from the start of the stacked arguments for a
5398 parm passed in mode PASSED_MODE and with type TYPE.
5400 INITIAL_OFFSET_PTR points to the current offset into the stacked
5403 The starting offset and size for this parm are returned in
5404 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5405 nonzero, the offset is that of stack slot, which is returned in
5406 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5407 padding required from the initial offset ptr to the stack slot.
5409 IN_REGS is nonzero if the argument will be passed in registers. It will
5410 never be set if REG_PARM_STACK_SPACE is not defined.
5412 FNDECL is the function in which the argument was defined.
5414 There are two types of rounding that are done. The first, controlled by
5415 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5416 list to be aligned to the specific boundary (in bits). This rounding
5417 affects the initial and starting offsets, but not the argument size.
5419 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5420 optionally rounds the size of the parm to PARM_BOUNDARY. The
5421 initial offset is not affected by this rounding, while the size always
5422 is and the starting offset may be. */
5424 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5425 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5426 callers pass in the total size of args so far as
5427 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5430 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
5431 int partial, tree fndecl ATTRIBUTE_UNUSED,
5432 struct args_size *initial_offset_ptr,
5433 struct locate_and_pad_arg_data *locate)
5436 enum direction where_pad;
5438 int reg_parm_stack_space = 0;
5439 int part_size_in_regs;
5441 #ifdef REG_PARM_STACK_SPACE
5442 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5444 /* If we have found a stack parm before we reach the end of the
5445 area reserved for registers, skip that area. */
5448 if (reg_parm_stack_space > 0)
5450 if (initial_offset_ptr->var)
5452 initial_offset_ptr->var
5453 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5454 ssize_int (reg_parm_stack_space));
5455 initial_offset_ptr->constant = 0;
5457 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5458 initial_offset_ptr->constant = reg_parm_stack_space;
5461 #endif /* REG_PARM_STACK_SPACE */
5463 part_size_in_regs = 0;
5464 if (reg_parm_stack_space == 0)
5465 part_size_in_regs = ((partial * UNITS_PER_WORD)
5466 / (PARM_BOUNDARY / BITS_PER_UNIT)
5467 * (PARM_BOUNDARY / BITS_PER_UNIT));
5470 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5471 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5472 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5473 locate->where_pad = where_pad;
5475 #ifdef ARGS_GROW_DOWNWARD
5476 locate->slot_offset.constant = -initial_offset_ptr->constant;
5477 if (initial_offset_ptr->var)
5478 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
5479 initial_offset_ptr->var);
5483 if (where_pad != none
5484 && (!host_integerp (sizetree, 1)
5485 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5486 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5487 SUB_PARM_SIZE (locate->slot_offset, s2);
5490 locate->slot_offset.constant += part_size_in_regs;
5493 #ifdef REG_PARM_STACK_SPACE
5494 || REG_PARM_STACK_SPACE (fndecl) > 0
5497 pad_to_arg_alignment (&locate->slot_offset, boundary,
5498 &locate->alignment_pad);
5500 locate->size.constant = (-initial_offset_ptr->constant
5501 - locate->slot_offset.constant);
5502 if (initial_offset_ptr->var)
5503 locate->size.var = size_binop (MINUS_EXPR,
5504 size_binop (MINUS_EXPR,
5506 initial_offset_ptr->var),
5507 locate->slot_offset.var);
5509 /* Pad_below needs the pre-rounded size to know how much to pad
5511 locate->offset = locate->slot_offset;
5512 if (where_pad == downward)
5513 pad_below (&locate->offset, passed_mode, sizetree);
5515 #else /* !ARGS_GROW_DOWNWARD */
5517 #ifdef REG_PARM_STACK_SPACE
5518 || REG_PARM_STACK_SPACE (fndecl) > 0
5521 pad_to_arg_alignment (initial_offset_ptr, boundary,
5522 &locate->alignment_pad);
5523 locate->slot_offset = *initial_offset_ptr;
5525 #ifdef PUSH_ROUNDING
5526 if (passed_mode != BLKmode)
5527 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5530 /* Pad_below needs the pre-rounded size to know how much to pad below
5531 so this must be done before rounding up. */
5532 locate->offset = locate->slot_offset;
5533 if (where_pad == downward)
5534 pad_below (&locate->offset, passed_mode, sizetree);
5536 if (where_pad != none
5537 && (!host_integerp (sizetree, 1)
5538 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5539 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5541 ADD_PARM_SIZE (locate->size, sizetree);
5543 locate->size.constant -= part_size_in_regs;
5544 #endif /* ARGS_GROW_DOWNWARD */
5547 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5548 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5551 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
5552 struct args_size *alignment_pad)
5554 tree save_var = NULL_TREE;
5555 HOST_WIDE_INT save_constant = 0;
5556 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5557 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
5559 #ifdef SPARC_STACK_BOUNDARY_HACK
5560 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
5561 higher than the real alignment of %sp. However, when it does this,
5562 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
5563 This is a temporary hack while the sparc port is fixed. */
5564 if (SPARC_STACK_BOUNDARY_HACK)
5568 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5570 save_var = offset_ptr->var;
5571 save_constant = offset_ptr->constant;
5574 alignment_pad->var = NULL_TREE;
5575 alignment_pad->constant = 0;
5577 if (boundary > BITS_PER_UNIT)
5579 if (offset_ptr->var)
5581 tree sp_offset_tree = ssize_int (sp_offset);
5582 tree offset = size_binop (PLUS_EXPR,
5583 ARGS_SIZE_TREE (*offset_ptr),
5585 #ifdef ARGS_GROW_DOWNWARD
5586 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
5588 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
5591 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
5592 /* ARGS_SIZE_TREE includes constant term. */
5593 offset_ptr->constant = 0;
5594 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5595 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5600 offset_ptr->constant = -sp_offset +
5601 #ifdef ARGS_GROW_DOWNWARD
5602 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5604 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5606 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5607 alignment_pad->constant = offset_ptr->constant - save_constant;
5613 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
5615 if (passed_mode != BLKmode)
5617 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5618 offset_ptr->constant
5619 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5620 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5621 - GET_MODE_SIZE (passed_mode));
5625 if (TREE_CODE (sizetree) != INTEGER_CST
5626 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5628 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5629 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5631 ADD_PARM_SIZE (*offset_ptr, s2);
5632 SUB_PARM_SIZE (*offset_ptr, sizetree);
5637 /* Walk the tree of blocks describing the binding levels within a function
5638 and warn about variables the might be killed by setjmp or vfork.
5639 This is done after calling flow_analysis and before global_alloc
5640 clobbers the pseudo-regs to hard regs. */
5643 setjmp_vars_warning (tree block)
5647 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5649 if (TREE_CODE (decl) == VAR_DECL
5650 && DECL_RTL_SET_P (decl)
5651 && GET_CODE (DECL_RTL (decl)) == REG
5652 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5653 warning ("%Jvariable '%D' might be clobbered by `longjmp' or `vfork'",
5657 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5658 setjmp_vars_warning (sub);
5661 /* Do the appropriate part of setjmp_vars_warning
5662 but for arguments instead of local variables. */
5665 setjmp_args_warning (void)
5668 for (decl = DECL_ARGUMENTS (current_function_decl);
5669 decl; decl = TREE_CHAIN (decl))
5670 if (DECL_RTL (decl) != 0
5671 && GET_CODE (DECL_RTL (decl)) == REG
5672 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5673 warning ("%Jargument '%D' might be clobbered by `longjmp' or `vfork'",
5677 /* If this function call setjmp, put all vars into the stack
5678 unless they were declared `register'. */
5681 setjmp_protect (tree block)
5684 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5685 if ((TREE_CODE (decl) == VAR_DECL
5686 || TREE_CODE (decl) == PARM_DECL)
5687 && DECL_RTL (decl) != 0
5688 && (GET_CODE (DECL_RTL (decl)) == REG
5689 || (GET_CODE (DECL_RTL (decl)) == MEM
5690 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5691 /* If this variable came from an inline function, it must be
5692 that its life doesn't overlap the setjmp. If there was a
5693 setjmp in the function, it would already be in memory. We
5694 must exclude such variable because their DECL_RTL might be
5695 set to strange things such as virtual_stack_vars_rtx. */
5696 && ! DECL_FROM_INLINE (decl)
5698 #ifdef NON_SAVING_SETJMP
5699 /* If longjmp doesn't restore the registers,
5700 don't put anything in them. */
5704 ! DECL_REGISTER (decl)))
5705 put_var_into_stack (decl, /*rescan=*/true);
5706 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5707 setjmp_protect (sub);
5710 /* Like the previous function, but for args instead of local variables. */
5713 setjmp_protect_args (void)
5716 for (decl = DECL_ARGUMENTS (current_function_decl);
5717 decl; decl = TREE_CHAIN (decl))
5718 if ((TREE_CODE (decl) == VAR_DECL
5719 || TREE_CODE (decl) == PARM_DECL)
5720 && DECL_RTL (decl) != 0
5721 && (GET_CODE (DECL_RTL (decl)) == REG
5722 || (GET_CODE (DECL_RTL (decl)) == MEM
5723 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5725 /* If longjmp doesn't restore the registers,
5726 don't put anything in them. */
5727 #ifdef NON_SAVING_SETJMP
5731 ! DECL_REGISTER (decl)))
5732 put_var_into_stack (decl, /*rescan=*/true);
5735 /* Convert a stack slot address ADDR for variable VAR
5736 (from a containing function)
5737 into an address valid in this function (using a static chain). */
5740 fix_lexical_addr (rtx addr, tree var)
5743 HOST_WIDE_INT displacement;
5744 tree context = decl_function_context (var);
5745 struct function *fp;
5748 /* If this is the present function, we need not do anything. */
5749 if (context == current_function_decl)
5752 fp = find_function_data (context);
5754 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5755 addr = XEXP (XEXP (addr, 0), 0);
5757 /* Decode given address as base reg plus displacement. */
5758 if (GET_CODE (addr) == REG)
5759 basereg = addr, displacement = 0;
5760 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5761 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5768 /* Use same offset, relative to appropriate static chain or argument
5770 return plus_constant (base, displacement);
5773 /* Put all this function's BLOCK nodes including those that are chained
5774 onto the first block into a vector, and return it.
5775 Also store in each NOTE for the beginning or end of a block
5776 the index of that block in the vector.
5777 The arguments are BLOCK, the chain of top-level blocks of the function,
5778 and INSNS, the insn chain of the function. */
5781 identify_blocks (void)
5784 tree *block_vector, *last_block_vector;
5786 tree block = DECL_INITIAL (current_function_decl);
5791 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5792 depth-first order. */
5793 block_vector = get_block_vector (block, &n_blocks);
5794 block_stack = xmalloc (n_blocks * sizeof (tree));
5796 last_block_vector = identify_blocks_1 (get_insns (),
5798 block_vector + n_blocks,
5801 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5802 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5803 if (0 && last_block_vector != block_vector + n_blocks)
5806 free (block_vector);
5810 /* Subroutine of identify_blocks. Do the block substitution on the
5811 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5813 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5814 BLOCK_VECTOR is incremented for each block seen. */
5817 identify_blocks_1 (rtx insns, tree *block_vector, tree *end_block_vector,
5818 tree *orig_block_stack)
5821 tree *block_stack = orig_block_stack;
5823 for (insn = insns; insn; insn = NEXT_INSN (insn))
5825 if (GET_CODE (insn) == NOTE)
5827 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5831 /* If there are more block notes than BLOCKs, something
5833 if (block_vector == end_block_vector)
5836 b = *block_vector++;
5837 NOTE_BLOCK (insn) = b;
5840 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5842 /* If there are more NOTE_INSN_BLOCK_ENDs than
5843 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5844 if (block_stack == orig_block_stack)
5847 NOTE_BLOCK (insn) = *--block_stack;
5850 else if (GET_CODE (insn) == CALL_INSN
5851 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5853 rtx cp = PATTERN (insn);
5855 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5856 end_block_vector, block_stack);
5858 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5859 end_block_vector, block_stack);
5861 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5862 end_block_vector, block_stack);
5866 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5867 something is badly wrong. */
5868 if (block_stack != orig_block_stack)
5871 return block_vector;
5874 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5875 and create duplicate blocks. */
5876 /* ??? Need an option to either create block fragments or to create
5877 abstract origin duplicates of a source block. It really depends
5878 on what optimization has been performed. */
5881 reorder_blocks (void)
5883 tree block = DECL_INITIAL (current_function_decl);
5884 varray_type block_stack;
5886 if (block == NULL_TREE)
5889 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5891 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5892 clear_block_marks (block);
5894 /* Prune the old trees away, so that they don't get in the way. */
5895 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5896 BLOCK_CHAIN (block) = NULL_TREE;
5898 /* Recreate the block tree from the note nesting. */
5899 reorder_blocks_1 (get_insns (), block, &block_stack);
5900 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5902 /* Remove deleted blocks from the block fragment chains. */
5903 reorder_fix_fragments (block);
5906 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5909 clear_block_marks (tree block)
5913 TREE_ASM_WRITTEN (block) = 0;
5914 clear_block_marks (BLOCK_SUBBLOCKS (block));
5915 block = BLOCK_CHAIN (block);
5920 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack)
5924 for (insn = insns; insn; insn = NEXT_INSN (insn))
5926 if (GET_CODE (insn) == NOTE)
5928 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5930 tree block = NOTE_BLOCK (insn);
5932 /* If we have seen this block before, that means it now
5933 spans multiple address regions. Create a new fragment. */
5934 if (TREE_ASM_WRITTEN (block))
5936 tree new_block = copy_node (block);
5939 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5940 ? BLOCK_FRAGMENT_ORIGIN (block)
5942 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5943 BLOCK_FRAGMENT_CHAIN (new_block)
5944 = BLOCK_FRAGMENT_CHAIN (origin);
5945 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5947 NOTE_BLOCK (insn) = new_block;
5951 BLOCK_SUBBLOCKS (block) = 0;
5952 TREE_ASM_WRITTEN (block) = 1;
5953 /* When there's only one block for the entire function,
5954 current_block == block and we mustn't do this, it
5955 will cause infinite recursion. */
5956 if (block != current_block)
5958 BLOCK_SUPERCONTEXT (block) = current_block;
5959 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5960 BLOCK_SUBBLOCKS (current_block) = block;
5961 current_block = block;
5963 VARRAY_PUSH_TREE (*p_block_stack, block);
5965 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5967 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5968 VARRAY_POP (*p_block_stack);
5969 BLOCK_SUBBLOCKS (current_block)
5970 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5971 current_block = BLOCK_SUPERCONTEXT (current_block);
5974 else if (GET_CODE (insn) == CALL_INSN
5975 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5977 rtx cp = PATTERN (insn);
5978 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5980 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5982 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5987 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
5988 appears in the block tree, select one of the fragments to become
5989 the new origin block. */
5992 reorder_fix_fragments (tree block)
5996 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
5997 tree new_origin = NULL_TREE;
6001 if (! TREE_ASM_WRITTEN (dup_origin))
6003 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6005 /* Find the first of the remaining fragments. There must
6006 be at least one -- the current block. */
6007 while (! TREE_ASM_WRITTEN (new_origin))
6008 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6009 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6012 else if (! dup_origin)
6015 /* Re-root the rest of the fragments to the new origin. In the
6016 case that DUP_ORIGIN was null, that means BLOCK was the origin
6017 of a chain of fragments and we want to remove those fragments
6018 that didn't make it to the output. */
6021 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6026 if (TREE_ASM_WRITTEN (chain))
6028 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6030 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6032 chain = BLOCK_FRAGMENT_CHAIN (chain);
6037 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6038 block = BLOCK_CHAIN (block);
6042 /* Reverse the order of elements in the chain T of blocks,
6043 and return the new head of the chain (old last element). */
6046 blocks_nreverse (tree t)
6048 tree prev = 0, decl, next;
6049 for (decl = t; decl; decl = next)
6051 next = BLOCK_CHAIN (decl);
6052 BLOCK_CHAIN (decl) = prev;
6058 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6059 non-NULL, list them all into VECTOR, in a depth-first preorder
6060 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6064 all_blocks (tree block, tree *vector)
6070 TREE_ASM_WRITTEN (block) = 0;
6072 /* Record this block. */
6074 vector[n_blocks] = block;
6078 /* Record the subblocks, and their subblocks... */
6079 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6080 vector ? vector + n_blocks : 0);
6081 block = BLOCK_CHAIN (block);
6087 /* Return a vector containing all the blocks rooted at BLOCK. The
6088 number of elements in the vector is stored in N_BLOCKS_P. The
6089 vector is dynamically allocated; it is the caller's responsibility
6090 to call `free' on the pointer returned. */
6093 get_block_vector (tree block, int *n_blocks_p)
6097 *n_blocks_p = all_blocks (block, NULL);
6098 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
6099 all_blocks (block, block_vector);
6101 return block_vector;
6104 static GTY(()) int next_block_index = 2;
6106 /* Set BLOCK_NUMBER for all the blocks in FN. */
6109 number_blocks (tree fn)
6115 /* For SDB and XCOFF debugging output, we start numbering the blocks
6116 from 1 within each function, rather than keeping a running
6118 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6119 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6120 next_block_index = 1;
6123 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6125 /* The top-level BLOCK isn't numbered at all. */
6126 for (i = 1; i < n_blocks; ++i)
6127 /* We number the blocks from two. */
6128 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6130 free (block_vector);
6135 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6138 debug_find_var_in_block_tree (tree var, tree block)
6142 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6146 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6148 tree ret = debug_find_var_in_block_tree (var, t);
6156 /* Allocate a function structure for FNDECL and set its contents
6160 allocate_struct_function (tree fndecl)
6163 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
6165 cfun = ggc_alloc_cleared (sizeof (struct function));
6167 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6169 cfun->stack_alignment_needed = STACK_BOUNDARY;
6170 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6172 current_function_funcdef_no = funcdef_no++;
6174 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6176 init_stmt_for_function ();
6177 init_eh_for_function ();
6179 lang_hooks.function.init (cfun);
6180 if (init_machine_status)
6181 cfun->machine = (*init_machine_status) ();
6186 DECL_STRUCT_FUNCTION (fndecl) = cfun;
6187 cfun->decl = fndecl;
6189 result = DECL_RESULT (fndecl);
6190 if (aggregate_value_p (result, fndecl))
6192 #ifdef PCC_STATIC_STRUCT_RETURN
6193 current_function_returns_pcc_struct = 1;
6195 current_function_returns_struct = 1;
6198 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
6200 current_function_stdarg
6202 && TYPE_ARG_TYPES (fntype) != 0
6203 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
6204 != void_type_node));
6207 /* Reset cfun, and other non-struct-function variables to defaults as
6208 appropriate for emitting rtl at the start of a function. */
6211 prepare_function_start (tree fndecl)
6213 if (fndecl && DECL_STRUCT_FUNCTION (fndecl))
6214 cfun = DECL_STRUCT_FUNCTION (fndecl);
6216 allocate_struct_function (fndecl);
6218 init_varasm_status (cfun);
6221 cse_not_expected = ! optimize;
6223 /* Caller save not needed yet. */
6224 caller_save_needed = 0;
6226 /* We haven't done register allocation yet. */
6229 /* Indicate that we need to distinguish between the return value of the
6230 present function and the return value of a function being called. */
6231 rtx_equal_function_value_matters = 1;
6233 /* Indicate that we have not instantiated virtual registers yet. */
6234 virtuals_instantiated = 0;
6236 /* Indicate that we want CONCATs now. */
6237 generating_concat_p = 1;
6239 /* Indicate we have no need of a frame pointer yet. */
6240 frame_pointer_needed = 0;
6243 /* Initialize the rtl expansion mechanism so that we can do simple things
6244 like generate sequences. This is used to provide a context during global
6245 initialization of some passes. */
6247 init_dummy_function_start (void)
6249 prepare_function_start (NULL);
6252 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6253 and initialize static variables for generating RTL for the statements
6257 init_function_start (tree subr)
6259 prepare_function_start (subr);
6261 /* Within function body, compute a type's size as soon it is laid out. */
6262 immediate_size_expand++;
6264 /* Prevent ever trying to delete the first instruction of a
6265 function. Also tell final how to output a linenum before the
6266 function prologue. Note linenums could be missing, e.g. when
6267 compiling a Java .class file. */
6268 if (DECL_SOURCE_LINE (subr))
6269 emit_line_note (DECL_SOURCE_LOCATION (subr));
6271 /* Make sure first insn is a note even if we don't want linenums.
6272 This makes sure the first insn will never be deleted.
6273 Also, final expects a note to appear there. */
6274 emit_note (NOTE_INSN_DELETED);
6276 /* Warn if this value is an aggregate type,
6277 regardless of which calling convention we are using for it. */
6278 if (warn_aggregate_return
6279 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6280 warning ("function returns an aggregate");
6283 /* Make sure all values used by the optimization passes have sane
6286 init_function_for_compilation (void)
6290 /* No prologue/epilogue insns yet. */
6291 VARRAY_GROW (prologue, 0);
6292 VARRAY_GROW (epilogue, 0);
6293 VARRAY_GROW (sibcall_epilogue, 0);
6296 /* Expand a call to __main at the beginning of a possible main function. */
6298 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6299 #undef HAS_INIT_SECTION
6300 #define HAS_INIT_SECTION
6304 expand_main_function (void)
6306 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6307 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6309 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6313 /* Forcibly align the stack. */
6314 #ifdef STACK_GROWS_DOWNWARD
6315 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6316 stack_pointer_rtx, 1, OPTAB_WIDEN);
6318 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6319 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6320 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6321 stack_pointer_rtx, 1, OPTAB_WIDEN);
6323 if (tmp != stack_pointer_rtx)
6324 emit_move_insn (stack_pointer_rtx, tmp);
6326 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6327 tmp = force_reg (Pmode, const0_rtx);
6328 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6332 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6333 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6336 emit_insn_before (seq, tmp);
6342 #ifndef HAS_INIT_SECTION
6343 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6347 /* The PENDING_SIZES represent the sizes of variable-sized types.
6348 Create RTL for the various sizes now (using temporary variables),
6349 so that we can refer to the sizes from the RTL we are generating
6350 for the current function. The PENDING_SIZES are a TREE_LIST. The
6351 TREE_VALUE of each node is a SAVE_EXPR. */
6354 expand_pending_sizes (tree pending_sizes)
6358 /* Evaluate now the sizes of any types declared among the arguments. */
6359 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6361 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6362 /* Flush the queue in case this parameter declaration has
6368 /* Start the RTL for a new function, and set variables used for
6370 SUBR is the FUNCTION_DECL node.
6371 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6372 the function's parameters, which must be run at any return statement. */
6375 expand_function_start (tree subr, int parms_have_cleanups)
6377 /* Make sure volatile mem refs aren't considered
6378 valid operands of arithmetic insns. */
6379 init_recog_no_volatile ();
6381 current_function_profile
6383 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6385 current_function_limit_stack
6386 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6388 /* If the parameters of this function need cleaning up, get a label
6389 for the beginning of the code which executes those cleanups. This must
6390 be done before doing anything with return_label. */
6391 if (parms_have_cleanups)
6392 cleanup_label = gen_label_rtx ();
6396 /* Make the label for return statements to jump to. Do not special
6397 case machines with special return instructions -- they will be
6398 handled later during jump, ifcvt, or epilogue creation. */
6399 return_label = gen_label_rtx ();
6401 /* Initialize rtx used to return the value. */
6402 /* Do this before assign_parms so that we copy the struct value address
6403 before any library calls that assign parms might generate. */
6405 /* Decide whether to return the value in memory or in a register. */
6406 if (aggregate_value_p (DECL_RESULT (subr), subr))
6408 /* Returning something that won't go in a register. */
6409 rtx value_address = 0;
6411 #ifdef PCC_STATIC_STRUCT_RETURN
6412 if (current_function_returns_pcc_struct)
6414 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6415 value_address = assemble_static_space (size);
6420 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
6421 /* Expect to be passed the address of a place to store the value.
6422 If it is passed as an argument, assign_parms will take care of
6426 value_address = gen_reg_rtx (Pmode);
6427 emit_move_insn (value_address, sv);
6432 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6433 set_mem_attributes (x, DECL_RESULT (subr), 1);
6434 SET_DECL_RTL (DECL_RESULT (subr), x);
6437 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6438 /* If return mode is void, this decl rtl should not be used. */
6439 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6442 /* Compute the return values into a pseudo reg, which we will copy
6443 into the true return register after the cleanups are done. */
6445 /* In order to figure out what mode to use for the pseudo, we
6446 figure out what the mode of the eventual return register will
6447 actually be, and use that. */
6449 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6452 /* Structures that are returned in registers are not aggregate_value_p,
6453 so we may see a PARALLEL or a REG. */
6454 if (REG_P (hard_reg))
6455 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6456 else if (GET_CODE (hard_reg) == PARALLEL)
6457 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6461 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6462 result to the real return register(s). */
6463 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6466 /* Initialize rtx for parameters and local variables.
6467 In some cases this requires emitting insns. */
6468 assign_parms (subr);
6470 /* If function gets a static chain arg, store it. */
6471 if (cfun->static_chain_decl)
6475 expand_var (cfun->static_chain_decl);
6476 x = expand_expr (cfun->static_chain_decl, NULL_RTX,
6477 VOIDmode, EXPAND_WRITE);
6478 emit_move_insn (x, static_chain_incoming_rtx);
6481 /* If the function receives a non-local goto, then store the
6482 bits we need to restore the frame pointer. */
6483 if (cfun->nonlocal_goto_save_area)
6488 /* ??? We need to do this save early. Unfortunately here is
6489 before the frame variable gets declared. Help out... */
6490 expand_var (TREE_OPERAND (cfun->nonlocal_goto_save_area, 0));
6492 t_save = build (ARRAY_REF, ptr_type_node, cfun->nonlocal_goto_save_area,
6494 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
6496 emit_move_insn (r_save, virtual_stack_vars_rtx);
6497 update_nonlocal_goto_save_area ();
6500 /* The following was moved from init_function_start.
6501 The move is supposed to make sdb output more accurate. */
6502 /* Indicate the beginning of the function body,
6503 as opposed to parm setup. */
6504 emit_note (NOTE_INSN_FUNCTION_BEG);
6506 if (GET_CODE (get_last_insn ()) != NOTE)
6507 emit_note (NOTE_INSN_DELETED);
6508 parm_birth_insn = get_last_insn ();
6510 if (current_function_profile)
6513 PROFILE_HOOK (current_function_funcdef_no);
6517 /* After the display initializations is where the tail-recursion label
6518 should go, if we end up needing one. Ensure we have a NOTE here
6519 since some things (like trampolines) get placed before this. */
6520 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
6522 /* Evaluate now the sizes of any types declared among the arguments. */
6523 expand_pending_sizes (nreverse (get_pending_sizes ()));
6525 /* Make sure there is a line number after the function entry setup code. */
6526 force_next_line_note ();
6529 /* Undo the effects of init_dummy_function_start. */
6531 expand_dummy_function_end (void)
6533 /* End any sequences that failed to be closed due to syntax errors. */
6534 while (in_sequence_p ())
6537 /* Outside function body, can't compute type's actual size
6538 until next function's body starts. */
6540 free_after_parsing (cfun);
6541 free_after_compilation (cfun);
6545 /* Call DOIT for each hard register used as a return value from
6546 the current function. */
6549 diddle_return_value (void (*doit) (rtx, void *), void *arg)
6551 rtx outgoing = current_function_return_rtx;
6556 if (GET_CODE (outgoing) == REG)
6557 (*doit) (outgoing, arg);
6558 else if (GET_CODE (outgoing) == PARALLEL)
6562 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6564 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6566 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6573 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6575 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6579 clobber_return_register (void)
6581 diddle_return_value (do_clobber_return_reg, NULL);
6583 /* In case we do use pseudo to return value, clobber it too. */
6584 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6586 tree decl_result = DECL_RESULT (current_function_decl);
6587 rtx decl_rtl = DECL_RTL (decl_result);
6588 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6590 do_clobber_return_reg (decl_rtl, NULL);
6596 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6598 emit_insn (gen_rtx_USE (VOIDmode, reg));
6602 use_return_register (void)
6604 diddle_return_value (do_use_return_reg, NULL);
6607 /* Possibly warn about unused parameters. */
6609 do_warn_unused_parameter (tree fn)
6613 for (decl = DECL_ARGUMENTS (fn);
6614 decl; decl = TREE_CHAIN (decl))
6615 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6616 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl))
6617 warning ("%Junused parameter '%D'", decl, decl);
6620 static GTY(()) rtx initial_trampoline;
6622 /* Generate RTL for the end of the current function. */
6625 expand_function_end (void)
6629 finish_expr_for_function ();
6631 /* If arg_pointer_save_area was referenced only from a nested
6632 function, we will not have initialized it yet. Do that now. */
6633 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6634 get_arg_pointer_save_area (cfun);
6636 #ifdef NON_SAVING_SETJMP
6637 /* Don't put any variables in registers if we call setjmp
6638 on a machine that fails to restore the registers. */
6639 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6641 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6642 setjmp_protect (DECL_INITIAL (current_function_decl));
6644 setjmp_protect_args ();
6648 /* If we are doing stack checking and this function makes calls,
6649 do a stack probe at the start of the function to ensure we have enough
6650 space for another stack frame. */
6651 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6655 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6656 if (GET_CODE (insn) == CALL_INSN)
6659 probe_stack_range (STACK_CHECK_PROTECT,
6660 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6663 emit_insn_before (seq, tail_recursion_reentry);
6668 /* Possibly warn about unused parameters.
6669 When frontend does unit-at-a-time, the warning is already
6670 issued at finalization time. */
6671 if (warn_unused_parameter
6672 && !lang_hooks.callgraph.expand_function)
6673 do_warn_unused_parameter (current_function_decl);
6675 /* End any sequences that failed to be closed due to syntax errors. */
6676 while (in_sequence_p ())
6679 /* Outside function body, can't compute type's actual size
6680 until next function's body starts. */
6681 immediate_size_expand--;
6683 clear_pending_stack_adjust ();
6684 do_pending_stack_adjust ();
6686 /* @@@ This is a kludge. We want to ensure that instructions that
6687 may trap are not moved into the epilogue by scheduling, because
6688 we don't always emit unwind information for the epilogue.
6689 However, not all machine descriptions define a blockage insn, so
6690 emit an ASM_INPUT to act as one. */
6691 if (flag_non_call_exceptions)
6692 emit_insn (gen_rtx_ASM_INPUT (VOIDmode, ""));
6694 /* Mark the end of the function body.
6695 If control reaches this insn, the function can drop through
6696 without returning a value. */
6697 emit_note (NOTE_INSN_FUNCTION_END);
6699 /* Must mark the last line number note in the function, so that the test
6700 coverage code can avoid counting the last line twice. This just tells
6701 the code to ignore the immediately following line note, since there
6702 already exists a copy of this note somewhere above. This line number
6703 note is still needed for debugging though, so we can't delete it. */
6704 if (flag_test_coverage)
6705 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
6707 /* Output a linenumber for the end of the function.
6708 SDB depends on this. */
6709 force_next_line_note ();
6710 emit_line_note (input_location);
6712 /* Before the return label (if any), clobber the return
6713 registers so that they are not propagated live to the rest of
6714 the function. This can only happen with functions that drop
6715 through; if there had been a return statement, there would
6716 have either been a return rtx, or a jump to the return label.
6718 We delay actual code generation after the current_function_value_rtx
6720 clobber_after = get_last_insn ();
6722 /* Output the label for the actual return from the function,
6723 if one is expected. This happens either because a function epilogue
6724 is used instead of a return instruction, or because a return was done
6725 with a goto in order to run local cleanups, or because of pcc-style
6726 structure returning. */
6728 emit_label (return_label);
6730 /* Let except.c know where it should emit the call to unregister
6731 the function context for sjlj exceptions. */
6732 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6733 sjlj_emit_function_exit_after (get_last_insn ());
6735 /* If we had calls to alloca, and this machine needs
6736 an accurate stack pointer to exit the function,
6737 insert some code to save and restore the stack pointer. */
6738 if (! EXIT_IGNORE_STACK
6739 && current_function_calls_alloca)
6743 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6744 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6747 /* If scalar return value was computed in a pseudo-reg, or was a named
6748 return value that got dumped to the stack, copy that to the hard
6750 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6752 tree decl_result = DECL_RESULT (current_function_decl);
6753 rtx decl_rtl = DECL_RTL (decl_result);
6755 if (REG_P (decl_rtl)
6756 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6757 : DECL_REGISTER (decl_result))
6759 rtx real_decl_rtl = current_function_return_rtx;
6761 /* This should be set in assign_parms. */
6762 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
6765 /* If this is a BLKmode structure being returned in registers,
6766 then use the mode computed in expand_return. Note that if
6767 decl_rtl is memory, then its mode may have been changed,
6768 but that current_function_return_rtx has not. */
6769 if (GET_MODE (real_decl_rtl) == BLKmode)
6770 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
6772 /* If a named return value dumped decl_return to memory, then
6773 we may need to re-do the PROMOTE_MODE signed/unsigned
6775 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6777 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
6779 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
6780 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6783 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6785 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6787 /* If expand_function_start has created a PARALLEL for decl_rtl,
6788 move the result to the real return registers. Otherwise, do
6789 a group load from decl_rtl for a named return. */
6790 if (GET_CODE (decl_rtl) == PARALLEL)
6791 emit_group_move (real_decl_rtl, decl_rtl);
6793 emit_group_load (real_decl_rtl, decl_rtl,
6794 TREE_TYPE (decl_result),
6795 int_size_in_bytes (TREE_TYPE (decl_result)));
6798 emit_move_insn (real_decl_rtl, decl_rtl);
6802 /* If returning a structure, arrange to return the address of the value
6803 in a place where debuggers expect to find it.
6805 If returning a structure PCC style,
6806 the caller also depends on this value.
6807 And current_function_returns_pcc_struct is not necessarily set. */
6808 if (current_function_returns_struct
6809 || current_function_returns_pcc_struct)
6812 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6813 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6814 #ifdef FUNCTION_OUTGOING_VALUE
6816 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6817 current_function_decl);
6820 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6823 /* Mark this as a function return value so integrate will delete the
6824 assignment and USE below when inlining this function. */
6825 REG_FUNCTION_VALUE_P (outgoing) = 1;
6827 /* The address may be ptr_mode and OUTGOING may be Pmode. */
6828 value_address = convert_memory_address (GET_MODE (outgoing),
6831 emit_move_insn (outgoing, value_address);
6833 /* Show return register used to hold result (in this case the address
6835 current_function_return_rtx = outgoing;
6838 /* If this is an implementation of throw, do what's necessary to
6839 communicate between __builtin_eh_return and the epilogue. */
6840 expand_eh_return ();
6842 /* Emit the actual code to clobber return register. */
6847 clobber_return_register ();
6851 after = emit_insn_after (seq, clobber_after);
6854 /* Output the label for the naked return from the function, if one is
6855 expected. This is currently used only by __builtin_return. */
6856 if (naked_return_label)
6857 emit_label (naked_return_label);
6859 /* ??? This should no longer be necessary since stupid is no longer with
6860 us, but there are some parts of the compiler (eg reload_combine, and
6861 sh mach_dep_reorg) that still try and compute their own lifetime info
6862 instead of using the general framework. */
6863 use_return_register ();
6865 /* Fix up any gotos that jumped out to the outermost
6866 binding level of the function.
6867 Must follow emitting RETURN_LABEL. */
6869 /* If you have any cleanups to do at this point,
6870 and they need to create temporary variables,
6871 then you will lose. */
6872 expand_fixups (get_insns ());
6876 get_arg_pointer_save_area (struct function *f)
6878 rtx ret = f->x_arg_pointer_save_area;
6882 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
6883 f->x_arg_pointer_save_area = ret;
6886 if (f == cfun && ! f->arg_pointer_save_area_init)
6890 /* Save the arg pointer at the beginning of the function. The
6891 generated stack slot may not be a valid memory address, so we
6892 have to check it and fix it if necessary. */
6894 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
6898 push_topmost_sequence ();
6899 emit_insn_after (seq, get_insns ());
6900 pop_topmost_sequence ();
6906 /* Extend a vector that records the INSN_UIDs of INSNS
6907 (a list of one or more insns). */
6910 record_insns (rtx insns, varray_type *vecp)
6917 while (tmp != NULL_RTX)
6920 tmp = NEXT_INSN (tmp);
6923 i = VARRAY_SIZE (*vecp);
6924 VARRAY_GROW (*vecp, i + len);
6926 while (tmp != NULL_RTX)
6928 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
6930 tmp = NEXT_INSN (tmp);
6934 /* Set the locator of the insn chain starting at INSN to LOC. */
6936 set_insn_locators (rtx insn, int loc)
6938 while (insn != NULL_RTX)
6941 INSN_LOCATOR (insn) = loc;
6942 insn = NEXT_INSN (insn);
6946 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
6947 be running after reorg, SEQUENCE rtl is possible. */
6950 contains (rtx insn, varray_type vec)
6954 if (GET_CODE (insn) == INSN
6955 && GET_CODE (PATTERN (insn)) == SEQUENCE)
6958 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
6959 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
6960 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
6966 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
6967 if (INSN_UID (insn) == VARRAY_INT (vec, j))
6974 prologue_epilogue_contains (rtx insn)
6976 if (contains (insn, prologue))
6978 if (contains (insn, epilogue))
6984 sibcall_epilogue_contains (rtx insn)
6986 if (sibcall_epilogue)
6987 return contains (insn, sibcall_epilogue);
6992 /* Insert gen_return at the end of block BB. This also means updating
6993 block_for_insn appropriately. */
6996 emit_return_into_block (basic_block bb, rtx line_note)
6998 emit_jump_insn_after (gen_return (), BB_END (bb));
7000 emit_note_copy_after (line_note, PREV_INSN (BB_END (bb)));
7002 #endif /* HAVE_return */
7004 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7006 /* These functions convert the epilogue into a variant that does not modify the
7007 stack pointer. This is used in cases where a function returns an object
7008 whose size is not known until it is computed. The called function leaves the
7009 object on the stack, leaves the stack depressed, and returns a pointer to
7012 What we need to do is track all modifications and references to the stack
7013 pointer, deleting the modifications and changing the references to point to
7014 the location the stack pointer would have pointed to had the modifications
7017 These functions need to be portable so we need to make as few assumptions
7018 about the epilogue as we can. However, the epilogue basically contains
7019 three things: instructions to reset the stack pointer, instructions to
7020 reload registers, possibly including the frame pointer, and an
7021 instruction to return to the caller.
7023 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7024 We also make no attempt to validate the insns we make since if they are
7025 invalid, we probably can't do anything valid. The intent is that these
7026 routines get "smarter" as more and more machines start to use them and
7027 they try operating on different epilogues.
7029 We use the following structure to track what the part of the epilogue that
7030 we've already processed has done. We keep two copies of the SP equivalence,
7031 one for use during the insn we are processing and one for use in the next
7032 insn. The difference is because one part of a PARALLEL may adjust SP
7033 and the other may use it. */
7037 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7038 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7039 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7040 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7041 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7042 should be set to once we no longer need
7044 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences
7048 static void handle_epilogue_set (rtx, struct epi_info *);
7049 static void update_epilogue_consts (rtx, rtx, void *);
7050 static void emit_equiv_load (struct epi_info *);
7052 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7053 no modifications to the stack pointer. Return the new list of insns. */
7056 keep_stack_depressed (rtx insns)
7059 struct epi_info info;
7062 /* If the epilogue is just a single instruction, it must be OK as is. */
7063 if (NEXT_INSN (insns) == NULL_RTX)
7066 /* Otherwise, start a sequence, initialize the information we have, and
7067 process all the insns we were given. */
7070 info.sp_equiv_reg = stack_pointer_rtx;
7072 info.equiv_reg_src = 0;
7074 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
7075 info.const_equiv[j] = 0;
7079 while (insn != NULL_RTX)
7081 next = NEXT_INSN (insn);
7090 /* If this insn references the register that SP is equivalent to and
7091 we have a pending load to that register, we must force out the load
7092 first and then indicate we no longer know what SP's equivalent is. */
7093 if (info.equiv_reg_src != 0
7094 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7096 emit_equiv_load (&info);
7097 info.sp_equiv_reg = 0;
7100 info.new_sp_equiv_reg = info.sp_equiv_reg;
7101 info.new_sp_offset = info.sp_offset;
7103 /* If this is a (RETURN) and the return address is on the stack,
7104 update the address and change to an indirect jump. */
7105 if (GET_CODE (PATTERN (insn)) == RETURN
7106 || (GET_CODE (PATTERN (insn)) == PARALLEL
7107 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7109 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7111 HOST_WIDE_INT offset = 0;
7112 rtx jump_insn, jump_set;
7114 /* If the return address is in a register, we can emit the insn
7115 unchanged. Otherwise, it must be a MEM and we see what the
7116 base register and offset are. In any case, we have to emit any
7117 pending load to the equivalent reg of SP, if any. */
7118 if (GET_CODE (retaddr) == REG)
7120 emit_equiv_load (&info);
7125 else if (GET_CODE (retaddr) == MEM
7126 && GET_CODE (XEXP (retaddr, 0)) == REG)
7127 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7128 else if (GET_CODE (retaddr) == MEM
7129 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7130 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7131 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7133 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7134 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7139 /* If the base of the location containing the return pointer
7140 is SP, we must update it with the replacement address. Otherwise,
7141 just build the necessary MEM. */
7142 retaddr = plus_constant (base, offset);
7143 if (base == stack_pointer_rtx)
7144 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7145 plus_constant (info.sp_equiv_reg,
7148 retaddr = gen_rtx_MEM (Pmode, retaddr);
7150 /* If there is a pending load to the equivalent register for SP
7151 and we reference that register, we must load our address into
7152 a scratch register and then do that load. */
7153 if (info.equiv_reg_src
7154 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7159 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7160 if (HARD_REGNO_MODE_OK (regno, Pmode)
7161 && !fixed_regs[regno]
7162 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7163 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7165 && !refers_to_regno_p (regno,
7166 regno + hard_regno_nregs[regno]
7168 info.equiv_reg_src, NULL)
7169 && info.const_equiv[regno] == 0)
7172 if (regno == FIRST_PSEUDO_REGISTER)
7175 reg = gen_rtx_REG (Pmode, regno);
7176 emit_move_insn (reg, retaddr);
7180 emit_equiv_load (&info);
7181 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7183 /* Show the SET in the above insn is a RETURN. */
7184 jump_set = single_set (jump_insn);
7188 SET_IS_RETURN_P (jump_set) = 1;
7191 /* If SP is not mentioned in the pattern and its equivalent register, if
7192 any, is not modified, just emit it. Otherwise, if neither is set,
7193 replace the reference to SP and emit the insn. If none of those are
7194 true, handle each SET individually. */
7195 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7196 && (info.sp_equiv_reg == stack_pointer_rtx
7197 || !reg_set_p (info.sp_equiv_reg, insn)))
7199 else if (! reg_set_p (stack_pointer_rtx, insn)
7200 && (info.sp_equiv_reg == stack_pointer_rtx
7201 || !reg_set_p (info.sp_equiv_reg, insn)))
7203 if (! validate_replace_rtx (stack_pointer_rtx,
7204 plus_constant (info.sp_equiv_reg,
7211 else if (GET_CODE (PATTERN (insn)) == SET)
7212 handle_epilogue_set (PATTERN (insn), &info);
7213 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7215 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7216 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7217 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7222 info.sp_equiv_reg = info.new_sp_equiv_reg;
7223 info.sp_offset = info.new_sp_offset;
7225 /* Now update any constants this insn sets. */
7226 note_stores (PATTERN (insn), update_epilogue_consts, &info);
7230 insns = get_insns ();
7235 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7236 structure that contains information about what we've seen so far. We
7237 process this SET by either updating that data or by emitting one or
7241 handle_epilogue_set (rtx set, struct epi_info *p)
7243 /* First handle the case where we are setting SP. Record what it is being
7244 set from. If unknown, abort. */
7245 if (reg_set_p (stack_pointer_rtx, set))
7247 if (SET_DEST (set) != stack_pointer_rtx)
7250 if (GET_CODE (SET_SRC (set)) == PLUS)
7252 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7253 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7254 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7255 else if (GET_CODE (XEXP (SET_SRC (set), 1)) == REG
7256 && REGNO (XEXP (SET_SRC (set), 1)) < FIRST_PSEUDO_REGISTER
7257 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))] != 0)
7259 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
7264 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7266 /* If we are adjusting SP, we adjust from the old data. */
7267 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7269 p->new_sp_equiv_reg = p->sp_equiv_reg;
7270 p->new_sp_offset += p->sp_offset;
7273 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7279 /* Next handle the case where we are setting SP's equivalent register.
7280 If we already have a value to set it to, abort. We could update, but
7281 there seems little point in handling that case. Note that we have
7282 to allow for the case where we are setting the register set in
7283 the previous part of a PARALLEL inside a single insn. But use the
7284 old offset for any updates within this insn. We must allow for the case
7285 where the register is being set in a different (usually wider) mode than
7287 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7289 if (p->equiv_reg_src != 0
7290 || GET_CODE (p->new_sp_equiv_reg) != REG
7291 || GET_CODE (SET_DEST (set)) != REG
7292 || GET_MODE_BITSIZE (GET_MODE (SET_DEST (set))) > BITS_PER_WORD
7293 || REGNO (p->new_sp_equiv_reg) != REGNO (SET_DEST (set)))
7297 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7298 plus_constant (p->sp_equiv_reg,
7302 /* Otherwise, replace any references to SP in the insn to its new value
7303 and emit the insn. */
7306 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7307 plus_constant (p->sp_equiv_reg,
7309 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7310 plus_constant (p->sp_equiv_reg,
7316 /* Update the tracking information for registers set to constants. */
7319 update_epilogue_consts (rtx dest, rtx x, void *data)
7321 struct epi_info *p = (struct epi_info *) data;
7324 if (GET_CODE (dest) != REG || REGNO (dest) >= FIRST_PSEUDO_REGISTER)
7327 /* If we are either clobbering a register or doing a partial set,
7328 show we don't know the value. */
7329 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x)))
7330 p->const_equiv[REGNO (dest)] = 0;
7332 /* If we are setting it to a constant, record that constant. */
7333 else if (GET_CODE (SET_SRC (x)) == CONST_INT)
7334 p->const_equiv[REGNO (dest)] = SET_SRC (x);
7336 /* If this is a binary operation between a register we have been tracking
7337 and a constant, see if we can compute a new constant value. */
7338 else if (ARITHMETIC_P (SET_SRC (x))
7339 && GET_CODE (XEXP (SET_SRC (x), 0)) == REG
7340 && REGNO (XEXP (SET_SRC (x), 0)) < FIRST_PSEUDO_REGISTER
7341 && p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))] != 0
7342 && GET_CODE (XEXP (SET_SRC (x), 1)) == CONST_INT
7343 && 0 != (new = simplify_binary_operation
7344 (GET_CODE (SET_SRC (x)), GET_MODE (dest),
7345 p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))],
7346 XEXP (SET_SRC (x), 1)))
7347 && GET_CODE (new) == CONST_INT)
7348 p->const_equiv[REGNO (dest)] = new;
7350 /* Otherwise, we can't do anything with this value. */
7352 p->const_equiv[REGNO (dest)] = 0;
7355 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7358 emit_equiv_load (struct epi_info *p)
7360 if (p->equiv_reg_src != 0)
7362 rtx dest = p->sp_equiv_reg;
7364 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest))
7365 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src),
7366 REGNO (p->sp_equiv_reg));
7368 emit_move_insn (dest, p->equiv_reg_src);
7369 p->equiv_reg_src = 0;
7374 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7375 this into place with notes indicating where the prologue ends and where
7376 the epilogue begins. Update the basic block information when possible. */
7379 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
7383 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7386 #ifdef HAVE_prologue
7387 rtx prologue_end = NULL_RTX;
7389 #if defined (HAVE_epilogue) || defined(HAVE_return)
7390 rtx epilogue_end = NULL_RTX;
7393 #ifdef HAVE_prologue
7397 seq = gen_prologue ();
7400 /* Retain a map of the prologue insns. */
7401 record_insns (seq, &prologue);
7402 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
7406 set_insn_locators (seq, prologue_locator);
7408 /* Can't deal with multiple successors of the entry block
7409 at the moment. Function should always have at least one
7411 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7414 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7419 /* If the exit block has no non-fake predecessors, we don't need
7421 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7422 if ((e->flags & EDGE_FAKE) == 0)
7428 if (optimize && HAVE_return)
7430 /* If we're allowed to generate a simple return instruction,
7431 then by definition we don't need a full epilogue. Examine
7432 the block that falls through to EXIT. If it does not
7433 contain any code, examine its predecessors and try to
7434 emit (conditional) return instructions. */
7440 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7441 if (e->flags & EDGE_FALLTHRU)
7447 /* Verify that there are no active instructions in the last block. */
7448 label = BB_END (last);
7449 while (label && GET_CODE (label) != CODE_LABEL)
7451 if (active_insn_p (label))
7453 label = PREV_INSN (label);
7456 if (BB_HEAD (last) == label && GET_CODE (label) == CODE_LABEL)
7458 rtx epilogue_line_note = NULL_RTX;
7460 /* Locate the line number associated with the closing brace,
7461 if we can find one. */
7462 for (seq = get_last_insn ();
7463 seq && ! active_insn_p (seq);
7464 seq = PREV_INSN (seq))
7465 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7467 epilogue_line_note = seq;
7471 for (e = last->pred; e; e = e_next)
7473 basic_block bb = e->src;
7476 e_next = e->pred_next;
7477 if (bb == ENTRY_BLOCK_PTR)
7481 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7484 /* If we have an unconditional jump, we can replace that
7485 with a simple return instruction. */
7486 if (simplejump_p (jump))
7488 emit_return_into_block (bb, epilogue_line_note);
7492 /* If we have a conditional jump, we can try to replace
7493 that with a conditional return instruction. */
7494 else if (condjump_p (jump))
7496 if (! redirect_jump (jump, 0, 0))
7499 /* If this block has only one successor, it both jumps
7500 and falls through to the fallthru block, so we can't
7502 if (bb->succ->succ_next == NULL)
7508 /* Fix up the CFG for the successful change we just made. */
7509 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7512 /* Emit a return insn for the exit fallthru block. Whether
7513 this is still reachable will be determined later. */
7515 emit_barrier_after (BB_END (last));
7516 emit_return_into_block (last, epilogue_line_note);
7517 epilogue_end = BB_END (last);
7518 last->succ->flags &= ~EDGE_FALLTHRU;
7523 #ifdef HAVE_epilogue
7526 /* Find the edge that falls through to EXIT. Other edges may exist
7527 due to RETURN instructions, but those don't need epilogues.
7528 There really shouldn't be a mixture -- either all should have
7529 been converted or none, however... */
7531 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7532 if (e->flags & EDGE_FALLTHRU)
7538 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
7540 seq = gen_epilogue ();
7542 #ifdef INCOMING_RETURN_ADDR_RTX
7543 /* If this function returns with the stack depressed and we can support
7544 it, massage the epilogue to actually do that. */
7545 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7546 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7547 seq = keep_stack_depressed (seq);
7550 emit_jump_insn (seq);
7552 /* Retain a map of the epilogue insns. */
7553 record_insns (seq, &epilogue);
7554 set_insn_locators (seq, epilogue_locator);
7559 insert_insn_on_edge (seq, e);
7566 commit_edge_insertions ();
7568 #ifdef HAVE_sibcall_epilogue
7569 /* Emit sibling epilogues before any sibling call sites. */
7570 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7572 basic_block bb = e->src;
7573 rtx insn = BB_END (bb);
7577 if (GET_CODE (insn) != CALL_INSN
7578 || ! SIBLING_CALL_P (insn))
7582 emit_insn (gen_sibcall_epilogue ());
7586 /* Retain a map of the epilogue insns. Used in life analysis to
7587 avoid getting rid of sibcall epilogue insns. Do this before we
7588 actually emit the sequence. */
7589 record_insns (seq, &sibcall_epilogue);
7590 set_insn_locators (seq, epilogue_locator);
7592 i = PREV_INSN (insn);
7593 newinsn = emit_insn_before (seq, insn);
7597 #ifdef HAVE_prologue
7598 /* This is probably all useless now that we use locators. */
7603 /* GDB handles `break f' by setting a breakpoint on the first
7604 line note after the prologue. Which means (1) that if
7605 there are line number notes before where we inserted the
7606 prologue we should move them, and (2) we should generate a
7607 note before the end of the first basic block, if there isn't
7610 ??? This behavior is completely broken when dealing with
7611 multiple entry functions. We simply place the note always
7612 into first basic block and let alternate entry points
7616 for (insn = prologue_end; insn; insn = prev)
7618 prev = PREV_INSN (insn);
7619 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7621 /* Note that we cannot reorder the first insn in the
7622 chain, since rest_of_compilation relies on that
7623 remaining constant. */
7626 reorder_insns (insn, insn, prologue_end);
7630 /* Find the last line number note in the first block. */
7631 for (insn = BB_END (ENTRY_BLOCK_PTR->next_bb);
7632 insn != prologue_end && insn;
7633 insn = PREV_INSN (insn))
7634 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7637 /* If we didn't find one, make a copy of the first line number
7641 for (insn = next_active_insn (prologue_end);
7643 insn = PREV_INSN (insn))
7644 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7646 emit_note_copy_after (insn, prologue_end);
7652 #ifdef HAVE_epilogue
7657 /* Similarly, move any line notes that appear after the epilogue.
7658 There is no need, however, to be quite so anal about the existence
7659 of such a note. Also move the NOTE_INSN_FUNCTION_END and (possibly)
7660 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
7662 for (insn = epilogue_end; insn; insn = next)
7664 next = NEXT_INSN (insn);
7665 if (GET_CODE (insn) == NOTE
7666 && (NOTE_LINE_NUMBER (insn) > 0
7667 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG
7668 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_END))
7669 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7675 /* Reposition the prologue-end and epilogue-begin notes after instruction
7676 scheduling and delayed branch scheduling. */
7679 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
7681 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7682 rtx insn, last, note;
7685 if ((len = VARRAY_SIZE (prologue)) > 0)
7689 /* Scan from the beginning until we reach the last prologue insn.
7690 We apparently can't depend on basic_block_{head,end} after
7692 for (insn = f; insn; insn = NEXT_INSN (insn))
7694 if (GET_CODE (insn) == NOTE)
7696 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7699 else if (contains (insn, prologue))
7709 /* Find the prologue-end note if we haven't already, and
7710 move it to just after the last prologue insn. */
7713 for (note = last; (note = NEXT_INSN (note));)
7714 if (GET_CODE (note) == NOTE
7715 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7719 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7720 if (GET_CODE (last) == CODE_LABEL)
7721 last = NEXT_INSN (last);
7722 reorder_insns (note, note, last);
7726 if ((len = VARRAY_SIZE (epilogue)) > 0)
7730 /* Scan from the end until we reach the first epilogue insn.
7731 We apparently can't depend on basic_block_{head,end} after
7733 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7735 if (GET_CODE (insn) == NOTE)
7737 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7740 else if (contains (insn, epilogue))
7750 /* Find the epilogue-begin note if we haven't already, and
7751 move it to just before the first epilogue insn. */
7754 for (note = insn; (note = PREV_INSN (note));)
7755 if (GET_CODE (note) == NOTE
7756 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7760 if (PREV_INSN (last) != note)
7761 reorder_insns (note, note, PREV_INSN (last));
7764 #endif /* HAVE_prologue or HAVE_epilogue */
7767 /* Called once, at initialization, to initialize function.c. */
7770 init_function_once (void)
7772 VARRAY_INT_INIT (prologue, 0, "prologue");
7773 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7774 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
7777 /* Resets insn_block_boundaries array. */
7780 reset_block_changes (void)
7782 VARRAY_TREE_INIT (cfun->ib_boundaries_block, 100, "ib_boundaries_block");
7783 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, NULL_TREE);
7786 /* Record the boundary for BLOCK. */
7788 record_block_change (tree block)
7796 last_block = VARRAY_TOP_TREE (cfun->ib_boundaries_block);
7797 VARRAY_POP (cfun->ib_boundaries_block);
7799 for (i = VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block); i < n; i++)
7800 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, last_block);
7802 VARRAY_PUSH_TREE (cfun->ib_boundaries_block, block);
7805 /* Finishes record of boundaries. */
7806 void finalize_block_changes (void)
7808 record_block_change (DECL_INITIAL (current_function_decl));
7811 /* For INSN return the BLOCK it belongs to. */
7813 check_block_change (rtx insn, tree *block)
7815 unsigned uid = INSN_UID (insn);
7817 if (uid >= VARRAY_ACTIVE_SIZE (cfun->ib_boundaries_block))
7820 *block = VARRAY_TREE (cfun->ib_boundaries_block, uid);
7823 /* Releases the ib_boundaries_block records. */
7825 free_block_changes (void)
7827 cfun->ib_boundaries_block = NULL;
7830 /* Returns the name of the current function. */
7832 current_function_name (void)
7834 return lang_hooks.decl_printable_name (cfun->decl, 2);
7837 #include "gt-function.h"