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 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"
66 #ifndef TRAMPOLINE_ALIGNMENT
67 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
70 #ifndef LOCAL_ALIGNMENT
71 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
74 #ifndef STACK_ALIGNMENT_NEEDED
75 #define STACK_ALIGNMENT_NEEDED 1
78 /* Some systems use __main in a way incompatible with its use in gcc, in these
79 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
80 give the same symbol without quotes for an alternative entry point. You
81 must define both, or neither. */
83 #define NAME__MAIN "__main"
86 /* Round a value to the lowest integer less than it that is a multiple of
87 the required alignment. Avoid using division in case the value is
88 negative. Assume the alignment is a power of two. */
89 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
91 /* Similar, but round to the next highest integer that meets the
93 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
95 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
96 during rtl generation. If they are different register numbers, this is
97 always true. It may also be true if
98 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
99 generation. See fix_lexical_addr for details. */
101 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
102 #define NEED_SEPARATE_AP
105 /* Nonzero if function being compiled doesn't contain any calls
106 (ignoring the prologue and epilogue). This is set prior to
107 local register allocation and is valid for the remaining
109 int current_function_is_leaf;
111 /* Nonzero if function being compiled doesn't contain any instructions
112 that can throw an exception. This is set prior to final. */
114 int current_function_nothrow;
116 /* Nonzero if function being compiled doesn't modify the stack pointer
117 (ignoring the prologue and epilogue). This is only valid after
118 life_analysis has run. */
119 int current_function_sp_is_unchanging;
121 /* Nonzero if the function being compiled is a leaf function which only
122 uses leaf registers. This is valid after reload (specifically after
123 sched2) and is useful only if the port defines LEAF_REGISTERS. */
124 int current_function_uses_only_leaf_regs;
126 /* Nonzero once virtual register instantiation has been done.
127 assign_stack_local uses frame_pointer_rtx when this is nonzero.
128 calls.c:emit_library_call_value_1 uses it to set up
129 post-instantiation libcalls. */
130 int virtuals_instantiated;
132 /* Nonzero if at least one trampoline has been created. */
133 int trampolines_created;
135 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
136 static GTY(()) int funcdef_no;
138 /* These variables hold pointers to functions to create and destroy
139 target specific, per-function data structures. */
140 struct machine_function * (*init_machine_status) (void);
142 /* The FUNCTION_DECL for an inline function currently being expanded. */
143 tree inline_function_decl;
145 /* The currently compiled function. */
146 struct function *cfun = 0;
148 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
149 static GTY(()) varray_type prologue;
150 static GTY(()) varray_type epilogue;
152 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
154 static GTY(()) varray_type sibcall_epilogue;
156 /* In order to evaluate some expressions, such as function calls returning
157 structures in memory, we need to temporarily allocate stack locations.
158 We record each allocated temporary in the following structure.
160 Associated with each temporary slot is a nesting level. When we pop up
161 one level, all temporaries associated with the previous level are freed.
162 Normally, all temporaries are freed after the execution of the statement
163 in which they were created. However, if we are inside a ({...}) grouping,
164 the result may be in a temporary and hence must be preserved. If the
165 result could be in a temporary, we preserve it if we can determine which
166 one it is in. If we cannot determine which temporary may contain the
167 result, all temporaries are preserved. A temporary is preserved by
168 pretending it was allocated at the previous nesting level.
170 Automatic variables are also assigned temporary slots, at the nesting
171 level where they are defined. They are marked a "kept" so that
172 free_temp_slots will not free them. */
174 struct temp_slot GTY(())
176 /* Points to next temporary slot. */
177 struct temp_slot *next;
178 /* The rtx to used to reference the slot. */
180 /* The rtx used to represent the address if not the address of the
181 slot above. May be an EXPR_LIST if multiple addresses exist. */
183 /* The alignment (in bits) of the slot. */
185 /* The size, in units, of the slot. */
187 /* The type of the object in the slot, or zero if it doesn't correspond
188 to a type. We use this to determine whether a slot can be reused.
189 It can be reused if objects of the type of the new slot will always
190 conflict with objects of the type of the old slot. */
192 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
194 /* Nonzero if this temporary is currently in use. */
196 /* Nonzero if this temporary has its address taken. */
198 /* Nesting level at which this slot is being used. */
200 /* Nonzero if this should survive a call to free_temp_slots. */
202 /* The offset of the slot from the frame_pointer, including extra space
203 for alignment. This info is for combine_temp_slots. */
204 HOST_WIDE_INT base_offset;
205 /* The size of the slot, including extra space for alignment. This
206 info is for combine_temp_slots. */
207 HOST_WIDE_INT full_size;
210 /* This structure is used to record MEMs or pseudos used to replace VAR, any
211 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
212 maintain this list in case two operands of an insn were required to match;
213 in that case we must ensure we use the same replacement. */
215 struct fixup_replacement GTY(())
219 struct fixup_replacement *next;
222 struct insns_for_mem_entry
226 /* These are the INSNs which reference the MEM. */
230 /* Forward declarations. */
232 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int,
234 static struct temp_slot *find_temp_slot_from_address (rtx);
235 static void put_reg_into_stack (struct function *, rtx, tree, enum machine_mode,
236 enum machine_mode, int, unsigned int, int, htab_t);
237 static void schedule_fixup_var_refs (struct function *, rtx, tree, enum machine_mode,
239 static void fixup_var_refs (rtx, enum machine_mode, int, rtx, htab_t);
240 static struct fixup_replacement
241 *find_fixup_replacement (struct fixup_replacement **, rtx);
242 static void fixup_var_refs_insns (rtx, rtx, enum machine_mode, int, int, rtx);
243 static void fixup_var_refs_insns_with_hash (htab_t, rtx, enum machine_mode, int, rtx);
244 static void fixup_var_refs_insn (rtx, rtx, enum machine_mode, int, int, rtx);
245 static void fixup_var_refs_1 (rtx, enum machine_mode, rtx *, rtx,
246 struct fixup_replacement **, rtx);
247 static rtx fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
248 static rtx walk_fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
249 static rtx fixup_stack_1 (rtx, rtx);
250 static void optimize_bit_field (rtx, rtx, rtx *);
251 static void instantiate_decls (tree, int);
252 static void instantiate_decls_1 (tree, int);
253 static void instantiate_decl (rtx, HOST_WIDE_INT, int);
254 static rtx instantiate_new_reg (rtx, HOST_WIDE_INT *);
255 static int instantiate_virtual_regs_1 (rtx *, rtx, int);
256 static void delete_handlers (void);
257 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
258 static void pad_below (struct args_size *, enum machine_mode, tree);
259 static rtx round_trampoline_addr (rtx);
260 static rtx adjust_trampoline_addr (rtx);
261 static tree *identify_blocks_1 (rtx, tree *, tree *, tree *);
262 static void reorder_blocks_0 (tree);
263 static void reorder_blocks_1 (rtx, tree, varray_type *);
264 static void reorder_fix_fragments (tree);
265 static tree blocks_nreverse (tree);
266 static int all_blocks (tree, tree *);
267 static tree *get_block_vector (tree, int *);
268 extern tree debug_find_var_in_block_tree (tree, tree);
269 /* We always define `record_insns' even if its not used so that we
270 can always export `prologue_epilogue_contains'. */
271 static void record_insns (rtx, varray_type *) ATTRIBUTE_UNUSED;
272 static int contains (rtx, varray_type);
274 static void emit_return_into_block (basic_block, rtx);
276 static void put_addressof_into_stack (rtx, htab_t);
277 static bool purge_addressof_1 (rtx *, rtx, int, int, int, htab_t);
278 static void purge_single_hard_subreg_set (rtx);
279 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
280 static rtx keep_stack_depressed (rtx);
282 static int is_addressof (rtx *, void *);
283 static hashval_t insns_for_mem_hash (const void *);
284 static int insns_for_mem_comp (const void *, const void *);
285 static int insns_for_mem_walk (rtx *, void *);
286 static void compute_insns_for_mem (rtx, rtx, htab_t);
287 static void prepare_function_start (void);
288 static void do_clobber_return_reg (rtx, void *);
289 static void do_use_return_reg (rtx, void *);
290 static void instantiate_virtual_regs_lossage (rtx);
291 static tree split_complex_args (tree);
292 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
294 /* Pointer to chain of `struct function' for containing functions. */
295 static GTY(()) struct function *outer_function_chain;
297 /* List of insns that were postponed by purge_addressof_1. */
298 static rtx postponed_insns;
300 /* Given a function decl for a containing function,
301 return the `struct function' for it. */
304 find_function_data (tree decl)
308 for (p = outer_function_chain; p; p = p->outer)
315 /* Save the current context for compilation of a nested function.
316 This is called from language-specific code. The caller should use
317 the enter_nested langhook to save any language-specific state,
318 since this function knows only about language-independent
322 push_function_context_to (tree context)
328 if (context == current_function_decl)
329 cfun->contains_functions = 1;
332 struct function *containing = find_function_data (context);
333 containing->contains_functions = 1;
338 init_dummy_function_start ();
341 p->outer = outer_function_chain;
342 outer_function_chain = p;
343 p->fixup_var_refs_queue = 0;
345 (*lang_hooks.function.enter_nested) (p);
351 push_function_context (void)
353 push_function_context_to (current_function_decl);
356 /* Restore the last saved context, at the end of a nested function.
357 This function is called from language-specific code. */
360 pop_function_context_from (tree context ATTRIBUTE_UNUSED)
362 struct function *p = outer_function_chain;
363 struct var_refs_queue *queue;
366 outer_function_chain = p->outer;
368 current_function_decl = p->decl;
371 restore_emit_status (p);
373 (*lang_hooks.function.leave_nested) (p);
375 /* Finish doing put_var_into_stack for any of our variables which became
376 addressable during the nested function. If only one entry has to be
377 fixed up, just do that one. Otherwise, first make a list of MEMs that
378 are not to be unshared. */
379 if (p->fixup_var_refs_queue == 0)
381 else if (p->fixup_var_refs_queue->next == 0)
382 fixup_var_refs (p->fixup_var_refs_queue->modified,
383 p->fixup_var_refs_queue->promoted_mode,
384 p->fixup_var_refs_queue->unsignedp,
385 p->fixup_var_refs_queue->modified, 0);
390 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
391 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
393 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
394 fixup_var_refs (queue->modified, queue->promoted_mode,
395 queue->unsignedp, list, 0);
399 p->fixup_var_refs_queue = 0;
401 /* Reset variables that have known state during rtx generation. */
402 rtx_equal_function_value_matters = 1;
403 virtuals_instantiated = 0;
404 generating_concat_p = 1;
408 pop_function_context (void)
410 pop_function_context_from (current_function_decl);
413 /* Clear out all parts of the state in F that can safely be discarded
414 after the function has been parsed, but not compiled, to let
415 garbage collection reclaim the memory. */
418 free_after_parsing (struct function *f)
420 /* f->expr->forced_labels is used by code generation. */
421 /* f->emit->regno_reg_rtx is used by code generation. */
422 /* f->varasm is used by code generation. */
423 /* f->eh->eh_return_stub_label is used by code generation. */
425 (*lang_hooks.function.final) (f);
429 /* Clear out all parts of the state in F that can safely be discarded
430 after the function has been compiled, to let garbage collection
431 reclaim the memory. */
434 free_after_compilation (struct function *f)
442 f->x_temp_slots = NULL;
443 f->arg_offset_rtx = NULL;
444 f->return_rtx = NULL;
445 f->internal_arg_pointer = NULL;
446 f->x_nonlocal_labels = NULL;
447 f->x_nonlocal_goto_handler_slots = NULL;
448 f->x_nonlocal_goto_handler_labels = NULL;
449 f->x_nonlocal_goto_stack_level = NULL;
450 f->x_cleanup_label = NULL;
451 f->x_return_label = NULL;
452 f->computed_goto_common_label = NULL;
453 f->computed_goto_common_reg = NULL;
454 f->x_save_expr_regs = NULL;
455 f->x_stack_slot_list = NULL;
456 f->x_rtl_expr_chain = NULL;
457 f->x_tail_recursion_label = NULL;
458 f->x_tail_recursion_reentry = NULL;
459 f->x_arg_pointer_save_area = NULL;
460 f->x_clobber_return_insn = NULL;
461 f->x_context_display = NULL;
462 f->x_trampoline_list = NULL;
463 f->x_parm_birth_insn = NULL;
464 f->x_last_parm_insn = NULL;
465 f->x_parm_reg_stack_loc = NULL;
466 f->fixup_var_refs_queue = NULL;
467 f->original_arg_vector = NULL;
468 f->original_decl_initial = NULL;
469 f->inl_last_parm_insn = NULL;
470 f->epilogue_delay_list = NULL;
473 /* Allocate fixed slots in the stack frame of the current function. */
475 /* Return size needed for stack frame based on slots so far allocated in
477 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
478 the caller may have to do that. */
481 get_func_frame_size (struct function *f)
483 #ifdef FRAME_GROWS_DOWNWARD
484 return -f->x_frame_offset;
486 return f->x_frame_offset;
490 /* Return size needed for stack frame based on slots so far allocated.
491 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
492 the caller may have to do that. */
494 get_frame_size (void)
496 return get_func_frame_size (cfun);
499 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
500 with machine mode MODE.
502 ALIGN controls the amount of alignment for the address of the slot:
503 0 means according to MODE,
504 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
505 positive specifies alignment boundary in bits.
507 We do not round to stack_boundary here.
509 FUNCTION specifies the function to allocate in. */
512 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
513 struct function *function)
516 int bigend_correction = 0;
518 int frame_off, frame_alignment, frame_phase;
525 alignment = BIGGEST_ALIGNMENT;
527 alignment = GET_MODE_ALIGNMENT (mode);
529 /* Allow the target to (possibly) increase the alignment of this
531 type = (*lang_hooks.types.type_for_mode) (mode, 0);
533 alignment = LOCAL_ALIGNMENT (type, alignment);
535 alignment /= BITS_PER_UNIT;
537 else if (align == -1)
539 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
540 size = CEIL_ROUND (size, alignment);
543 alignment = align / BITS_PER_UNIT;
545 #ifdef FRAME_GROWS_DOWNWARD
546 function->x_frame_offset -= size;
549 /* Ignore alignment we can't do with expected alignment of the boundary. */
550 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
551 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
553 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
554 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
556 /* Calculate how many bytes the start of local variables is off from
558 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
559 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
560 frame_phase = frame_off ? frame_alignment - frame_off : 0;
562 /* Round the frame offset to the specified alignment. The default is
563 to always honor requests to align the stack but a port may choose to
564 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
565 if (STACK_ALIGNMENT_NEEDED
569 /* We must be careful here, since FRAME_OFFSET might be negative and
570 division with a negative dividend isn't as well defined as we might
571 like. So we instead assume that ALIGNMENT is a power of two and
572 use logical operations which are unambiguous. */
573 #ifdef FRAME_GROWS_DOWNWARD
574 function->x_frame_offset
575 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
578 function->x_frame_offset
579 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
584 /* On a big-endian machine, if we are allocating more space than we will use,
585 use the least significant bytes of those that are allocated. */
586 if (BYTES_BIG_ENDIAN && mode != BLKmode)
587 bigend_correction = size - GET_MODE_SIZE (mode);
589 /* If we have already instantiated virtual registers, return the actual
590 address relative to the frame pointer. */
591 if (function == cfun && virtuals_instantiated)
592 addr = plus_constant (frame_pointer_rtx,
594 (frame_offset + bigend_correction
595 + STARTING_FRAME_OFFSET, Pmode));
597 addr = plus_constant (virtual_stack_vars_rtx,
599 (function->x_frame_offset + bigend_correction,
602 #ifndef FRAME_GROWS_DOWNWARD
603 function->x_frame_offset += size;
606 x = gen_rtx_MEM (mode, addr);
608 function->x_stack_slot_list
609 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
614 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
618 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
620 return assign_stack_local_1 (mode, size, align, cfun);
623 /* Allocate a temporary stack slot and record it for possible later
626 MODE is the machine mode to be given to the returned rtx.
628 SIZE is the size in units of the space required. We do no rounding here
629 since assign_stack_local will do any required rounding.
631 KEEP is 1 if this slot is to be retained after a call to
632 free_temp_slots. Automatic variables for a block are allocated
633 with this flag. KEEP is 2 if we allocate a longer term temporary,
634 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
635 if we are to allocate something at an inner level to be treated as
636 a variable in the block (e.g., a SAVE_EXPR).
638 TYPE is the type that will be used for the stack slot. */
641 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, int keep,
645 struct temp_slot *p, *best_p = 0;
648 /* If SIZE is -1 it means that somebody tried to allocate a temporary
649 of a variable size. */
654 align = BIGGEST_ALIGNMENT;
656 align = GET_MODE_ALIGNMENT (mode);
659 type = (*lang_hooks.types.type_for_mode) (mode, 0);
662 align = LOCAL_ALIGNMENT (type, align);
664 /* Try to find an available, already-allocated temporary of the proper
665 mode which meets the size and alignment requirements. Choose the
666 smallest one with the closest alignment. */
667 for (p = temp_slots; p; p = p->next)
668 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
670 && objects_must_conflict_p (p->type, type)
671 && (best_p == 0 || best_p->size > p->size
672 || (best_p->size == p->size && best_p->align > p->align)))
674 if (p->align == align && p->size == size)
682 /* Make our best, if any, the one to use. */
685 /* If there are enough aligned bytes left over, make them into a new
686 temp_slot so that the extra bytes don't get wasted. Do this only
687 for BLKmode slots, so that we can be sure of the alignment. */
688 if (GET_MODE (best_p->slot) == BLKmode)
690 int alignment = best_p->align / BITS_PER_UNIT;
691 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
693 if (best_p->size - rounded_size >= alignment)
695 p = ggc_alloc (sizeof (struct temp_slot));
696 p->in_use = p->addr_taken = 0;
697 p->size = best_p->size - rounded_size;
698 p->base_offset = best_p->base_offset + rounded_size;
699 p->full_size = best_p->full_size - rounded_size;
700 p->slot = gen_rtx_MEM (BLKmode,
701 plus_constant (XEXP (best_p->slot, 0),
703 p->align = best_p->align;
706 p->type = best_p->type;
707 p->next = temp_slots;
710 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
713 best_p->size = rounded_size;
714 best_p->full_size = rounded_size;
721 /* If we still didn't find one, make a new temporary. */
724 HOST_WIDE_INT frame_offset_old = frame_offset;
726 p = ggc_alloc (sizeof (struct temp_slot));
728 /* We are passing an explicit alignment request to assign_stack_local.
729 One side effect of that is assign_stack_local will not round SIZE
730 to ensure the frame offset remains suitably aligned.
732 So for requests which depended on the rounding of SIZE, we go ahead
733 and round it now. We also make sure ALIGNMENT is at least
734 BIGGEST_ALIGNMENT. */
735 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
737 p->slot = assign_stack_local (mode,
739 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
745 /* The following slot size computation is necessary because we don't
746 know the actual size of the temporary slot until assign_stack_local
747 has performed all the frame alignment and size rounding for the
748 requested temporary. Note that extra space added for alignment
749 can be either above or below this stack slot depending on which
750 way the frame grows. We include the extra space if and only if it
751 is above this slot. */
752 #ifdef FRAME_GROWS_DOWNWARD
753 p->size = frame_offset_old - frame_offset;
758 /* Now define the fields used by combine_temp_slots. */
759 #ifdef FRAME_GROWS_DOWNWARD
760 p->base_offset = frame_offset;
761 p->full_size = frame_offset_old - frame_offset;
763 p->base_offset = frame_offset_old;
764 p->full_size = frame_offset - frame_offset_old;
767 p->next = temp_slots;
773 p->rtl_expr = seq_rtl_expr;
778 p->level = target_temp_slot_level;
783 p->level = var_temp_slot_level;
788 p->level = temp_slot_level;
793 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
794 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
795 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
797 /* If we know the alias set for the memory that will be used, use
798 it. If there's no TYPE, then we don't know anything about the
799 alias set for the memory. */
800 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
801 set_mem_align (slot, align);
803 /* If a type is specified, set the relevant flags. */
806 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
807 && TYPE_READONLY (type));
808 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
809 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
815 /* Allocate a temporary stack slot and record it for possible later
816 reuse. First three arguments are same as in preceding function. */
819 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
821 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
824 /* Assign a temporary.
825 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
826 and so that should be used in error messages. In either case, we
827 allocate of the given type.
828 KEEP is as for assign_stack_temp.
829 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
830 it is 0 if a register is OK.
831 DONT_PROMOTE is 1 if we should not promote values in register
835 assign_temp (tree type_or_decl, int keep, int memory_required,
836 int dont_promote ATTRIBUTE_UNUSED)
839 enum machine_mode mode;
840 #ifndef PROMOTE_FOR_CALL_ONLY
844 if (DECL_P (type_or_decl))
845 decl = type_or_decl, type = TREE_TYPE (decl);
847 decl = NULL, type = type_or_decl;
849 mode = TYPE_MODE (type);
850 #ifndef PROMOTE_FOR_CALL_ONLY
851 unsignedp = TREE_UNSIGNED (type);
854 if (mode == BLKmode || memory_required)
856 HOST_WIDE_INT size = int_size_in_bytes (type);
859 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
860 problems with allocating the stack space. */
864 /* Unfortunately, we don't yet know how to allocate variable-sized
865 temporaries. However, sometimes we have a fixed upper limit on
866 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
867 instead. This is the case for Chill variable-sized strings. */
868 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
869 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
870 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
871 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
873 /* The size of the temporary may be too large to fit into an integer. */
874 /* ??? Not sure this should happen except for user silliness, so limit
875 this to things that aren't compiler-generated temporaries. The
876 rest of the time we'll abort in assign_stack_temp_for_type. */
877 if (decl && size == -1
878 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
880 error_with_decl (decl, "size of variable `%s' is too large");
884 tmp = assign_stack_temp_for_type (mode, size, keep, type);
888 #ifndef PROMOTE_FOR_CALL_ONLY
890 mode = promote_mode (type, mode, &unsignedp, 0);
893 return gen_reg_rtx (mode);
896 /* Combine temporary stack slots which are adjacent on the stack.
898 This allows for better use of already allocated stack space. This is only
899 done for BLKmode slots because we can be sure that we won't have alignment
900 problems in this case. */
903 combine_temp_slots (void)
905 struct temp_slot *p, *q;
906 struct temp_slot *prev_p, *prev_q;
909 /* We can't combine slots, because the information about which slot
910 is in which alias set will be lost. */
911 if (flag_strict_aliasing)
914 /* If there are a lot of temp slots, don't do anything unless
915 high levels of optimization. */
916 if (! flag_expensive_optimizations)
917 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
918 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
921 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
925 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
926 for (q = p->next, prev_q = p; q; q = prev_q->next)
929 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
931 if (p->base_offset + p->full_size == q->base_offset)
933 /* Q comes after P; combine Q into P. */
935 p->full_size += q->full_size;
938 else if (q->base_offset + q->full_size == p->base_offset)
940 /* P comes after Q; combine P into Q. */
942 q->full_size += p->full_size;
947 /* Either delete Q or advance past it. */
949 prev_q->next = q->next;
953 /* Either delete P or advance past it. */
957 prev_p->next = p->next;
959 temp_slots = p->next;
966 /* Find the temp slot corresponding to the object at address X. */
968 static struct temp_slot *
969 find_temp_slot_from_address (rtx x)
974 for (p = temp_slots; p; p = p->next)
979 else if (XEXP (p->slot, 0) == x
981 || (GET_CODE (x) == PLUS
982 && XEXP (x, 0) == virtual_stack_vars_rtx
983 && GET_CODE (XEXP (x, 1)) == CONST_INT
984 && INTVAL (XEXP (x, 1)) >= p->base_offset
985 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
988 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
989 for (next = p->address; next; next = XEXP (next, 1))
990 if (XEXP (next, 0) == x)
994 /* If we have a sum involving a register, see if it points to a temp
996 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
997 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
999 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1000 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1006 /* Indicate that NEW is an alternate way of referring to the temp slot
1007 that previously was known by OLD. */
1010 update_temp_slot_address (rtx old, rtx new)
1012 struct temp_slot *p;
1014 if (rtx_equal_p (old, new))
1017 p = find_temp_slot_from_address (old);
1019 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1020 is a register, see if one operand of the PLUS is a temporary
1021 location. If so, NEW points into it. Otherwise, if both OLD and
1022 NEW are a PLUS and if there is a register in common between them.
1023 If so, try a recursive call on those values. */
1026 if (GET_CODE (old) != PLUS)
1029 if (GET_CODE (new) == REG)
1031 update_temp_slot_address (XEXP (old, 0), new);
1032 update_temp_slot_address (XEXP (old, 1), new);
1035 else if (GET_CODE (new) != PLUS)
1038 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1039 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1040 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1041 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1042 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1043 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1044 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1045 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1050 /* Otherwise add an alias for the temp's address. */
1051 else if (p->address == 0)
1055 if (GET_CODE (p->address) != EXPR_LIST)
1056 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1058 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1062 /* If X could be a reference to a temporary slot, mark the fact that its
1063 address was taken. */
1066 mark_temp_addr_taken (rtx x)
1068 struct temp_slot *p;
1073 /* If X is not in memory or is at a constant address, it cannot be in
1074 a temporary slot. */
1075 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1078 p = find_temp_slot_from_address (XEXP (x, 0));
1083 /* If X could be a reference to a temporary slot, mark that slot as
1084 belonging to the to one level higher than the current level. If X
1085 matched one of our slots, just mark that one. Otherwise, we can't
1086 easily predict which it is, so upgrade all of them. Kept slots
1087 need not be touched.
1089 This is called when an ({...}) construct occurs and a statement
1090 returns a value in memory. */
1093 preserve_temp_slots (rtx x)
1095 struct temp_slot *p = 0;
1097 /* If there is no result, we still might have some objects whose address
1098 were taken, so we need to make sure they stay around. */
1101 for (p = temp_slots; p; p = p->next)
1102 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1108 /* If X is a register that is being used as a pointer, see if we have
1109 a temporary slot we know it points to. To be consistent with
1110 the code below, we really should preserve all non-kept slots
1111 if we can't find a match, but that seems to be much too costly. */
1112 if (GET_CODE (x) == REG && REG_POINTER (x))
1113 p = find_temp_slot_from_address (x);
1115 /* If X is not in memory or is at a constant address, it cannot be in
1116 a temporary slot, but it can contain something whose address was
1118 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1120 for (p = temp_slots; p; p = p->next)
1121 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1127 /* First see if we can find a match. */
1129 p = find_temp_slot_from_address (XEXP (x, 0));
1133 /* Move everything at our level whose address was taken to our new
1134 level in case we used its address. */
1135 struct temp_slot *q;
1137 if (p->level == temp_slot_level)
1139 for (q = temp_slots; q; q = q->next)
1140 if (q != p && q->addr_taken && q->level == p->level)
1149 /* Otherwise, preserve all non-kept slots at this level. */
1150 for (p = temp_slots; p; p = p->next)
1151 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1155 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1156 with that RTL_EXPR, promote it into a temporary slot at the present
1157 level so it will not be freed when we free slots made in the
1161 preserve_rtl_expr_result (rtx x)
1163 struct temp_slot *p;
1165 /* If X is not in memory or is at a constant address, it cannot be in
1166 a temporary slot. */
1167 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1170 /* If we can find a match, move it to our level unless it is already at
1172 p = find_temp_slot_from_address (XEXP (x, 0));
1175 p->level = MIN (p->level, temp_slot_level);
1182 /* Free all temporaries used so far. This is normally called at the end
1183 of generating code for a statement. Don't free any temporaries
1184 currently in use for an RTL_EXPR that hasn't yet been emitted.
1185 We could eventually do better than this since it can be reused while
1186 generating the same RTL_EXPR, but this is complex and probably not
1190 free_temp_slots (void)
1192 struct temp_slot *p;
1194 for (p = temp_slots; p; p = p->next)
1195 if (p->in_use && p->level == temp_slot_level && ! p->keep
1196 && p->rtl_expr == 0)
1199 combine_temp_slots ();
1202 /* Free all temporary slots used in T, an RTL_EXPR node. */
1205 free_temps_for_rtl_expr (tree t)
1207 struct temp_slot *p;
1209 for (p = temp_slots; p; p = p->next)
1210 if (p->rtl_expr == t)
1212 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1213 needs to be preserved. This can happen if a temporary in
1214 the RTL_EXPR was addressed; preserve_temp_slots will move
1215 the temporary into a higher level. */
1216 if (temp_slot_level <= p->level)
1219 p->rtl_expr = NULL_TREE;
1222 combine_temp_slots ();
1225 /* Mark all temporaries ever allocated in this function as not suitable
1226 for reuse until the current level is exited. */
1229 mark_all_temps_used (void)
1231 struct temp_slot *p;
1233 for (p = temp_slots; p; p = p->next)
1235 p->in_use = p->keep = 1;
1236 p->level = MIN (p->level, temp_slot_level);
1240 /* Push deeper into the nesting level for stack temporaries. */
1243 push_temp_slots (void)
1248 /* Pop a temporary nesting level. All slots in use in the current level
1252 pop_temp_slots (void)
1254 struct temp_slot *p;
1256 for (p = temp_slots; p; p = p->next)
1257 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1260 combine_temp_slots ();
1265 /* Initialize temporary slots. */
1268 init_temp_slots (void)
1270 /* We have not allocated any temporaries yet. */
1272 temp_slot_level = 0;
1273 var_temp_slot_level = 0;
1274 target_temp_slot_level = 0;
1277 /* Retroactively move an auto variable from a register to a stack
1278 slot. This is done when an address-reference to the variable is
1279 seen. If RESCAN is true, all previously emitted instructions are
1280 examined and modified to handle the fact that DECL is now
1284 put_var_into_stack (tree decl, int rescan)
1287 enum machine_mode promoted_mode, decl_mode;
1288 struct function *function = 0;
1290 int can_use_addressof;
1291 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1292 int usedp = (TREE_USED (decl)
1293 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1295 context = decl_function_context (decl);
1297 /* Get the current rtl used for this object and its original mode. */
1298 reg = (TREE_CODE (decl) == SAVE_EXPR
1299 ? SAVE_EXPR_RTL (decl)
1300 : DECL_RTL_IF_SET (decl));
1302 /* No need to do anything if decl has no rtx yet
1303 since in that case caller is setting TREE_ADDRESSABLE
1304 and a stack slot will be assigned when the rtl is made. */
1308 /* Get the declared mode for this object. */
1309 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1310 : DECL_MODE (decl));
1311 /* Get the mode it's actually stored in. */
1312 promoted_mode = GET_MODE (reg);
1314 /* If this variable comes from an outer function, find that
1315 function's saved context. Don't use find_function_data here,
1316 because it might not be in any active function.
1317 FIXME: Is that really supposed to happen?
1318 It does in ObjC at least. */
1319 if (context != current_function_decl && context != inline_function_decl)
1320 for (function = outer_function_chain; function; function = function->outer)
1321 if (function->decl == context)
1324 /* If this is a variable-size object with a pseudo to address it,
1325 put that pseudo into the stack, if the var is nonlocal. */
1326 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1327 && GET_CODE (reg) == MEM
1328 && GET_CODE (XEXP (reg, 0)) == REG
1329 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1331 reg = XEXP (reg, 0);
1332 decl_mode = promoted_mode = GET_MODE (reg);
1338 /* FIXME make it work for promoted modes too */
1339 && decl_mode == promoted_mode
1340 #ifdef NON_SAVING_SETJMP
1341 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1345 /* If we can't use ADDRESSOF, make sure we see through one we already
1347 if (! can_use_addressof && GET_CODE (reg) == MEM
1348 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1349 reg = XEXP (XEXP (reg, 0), 0);
1351 /* Now we should have a value that resides in one or more pseudo regs. */
1353 if (GET_CODE (reg) == REG)
1355 /* If this variable lives in the current function and we don't need
1356 to put things in the stack for the sake of setjmp, try to keep it
1357 in a register until we know we actually need the address. */
1358 if (can_use_addressof)
1359 gen_mem_addressof (reg, decl, rescan);
1361 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1362 decl_mode, volatilep, 0, usedp, 0);
1364 else if (GET_CODE (reg) == CONCAT)
1366 /* A CONCAT contains two pseudos; put them both in the stack.
1367 We do it so they end up consecutive.
1368 We fixup references to the parts only after we fixup references
1369 to the whole CONCAT, lest we do double fixups for the latter
1371 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1372 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1373 rtx lopart = XEXP (reg, 0);
1374 rtx hipart = XEXP (reg, 1);
1375 #ifdef FRAME_GROWS_DOWNWARD
1376 /* Since part 0 should have a lower address, do it second. */
1377 put_reg_into_stack (function, hipart, part_type, part_mode,
1378 part_mode, volatilep, 0, 0, 0);
1379 put_reg_into_stack (function, lopart, part_type, part_mode,
1380 part_mode, volatilep, 0, 0, 0);
1382 put_reg_into_stack (function, lopart, part_type, part_mode,
1383 part_mode, volatilep, 0, 0, 0);
1384 put_reg_into_stack (function, hipart, part_type, part_mode,
1385 part_mode, volatilep, 0, 0, 0);
1388 /* Change the CONCAT into a combined MEM for both parts. */
1389 PUT_CODE (reg, MEM);
1390 MEM_ATTRS (reg) = 0;
1392 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1393 already computed alias sets. Here we want to re-generate. */
1395 SET_DECL_RTL (decl, NULL);
1396 set_mem_attributes (reg, decl, 1);
1398 SET_DECL_RTL (decl, reg);
1400 /* The two parts are in memory order already.
1401 Use the lower parts address as ours. */
1402 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1403 /* Prevent sharing of rtl that might lose. */
1404 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1405 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1406 if (usedp && rescan)
1408 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1410 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1411 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1418 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1419 into the stack frame of FUNCTION (0 means the current function).
1420 DECL_MODE is the machine mode of the user-level data type.
1421 PROMOTED_MODE is the machine mode of the register.
1422 VOLATILE_P is nonzero if this is for a "volatile" decl.
1423 USED_P is nonzero if this reg might have already been used in an insn. */
1426 put_reg_into_stack (struct function *function, rtx reg, tree type,
1427 enum machine_mode promoted_mode, enum machine_mode decl_mode,
1428 int volatile_p, unsigned int original_regno, int used_p, htab_t ht)
1430 struct function *func = function ? function : cfun;
1432 unsigned int regno = original_regno;
1435 regno = REGNO (reg);
1437 if (regno < func->x_max_parm_reg)
1438 new = func->x_parm_reg_stack_loc[regno];
1441 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1443 PUT_CODE (reg, MEM);
1444 PUT_MODE (reg, decl_mode);
1445 XEXP (reg, 0) = XEXP (new, 0);
1446 MEM_ATTRS (reg) = 0;
1447 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1448 MEM_VOLATILE_P (reg) = volatile_p;
1450 /* If this is a memory ref that contains aggregate components,
1451 mark it as such for cse and loop optimize. If we are reusing a
1452 previously generated stack slot, then we need to copy the bit in
1453 case it was set for other reasons. For instance, it is set for
1454 __builtin_va_alist. */
1457 MEM_SET_IN_STRUCT_P (reg,
1458 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1459 set_mem_alias_set (reg, get_alias_set (type));
1463 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1466 /* Make sure that all refs to the variable, previously made
1467 when it was a register, are fixed up to be valid again.
1468 See function above for meaning of arguments. */
1471 schedule_fixup_var_refs (struct function *function, rtx reg, tree type,
1472 enum machine_mode promoted_mode, htab_t ht)
1474 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1478 struct var_refs_queue *temp;
1480 temp = ggc_alloc (sizeof (struct var_refs_queue));
1481 temp->modified = reg;
1482 temp->promoted_mode = promoted_mode;
1483 temp->unsignedp = unsigned_p;
1484 temp->next = function->fixup_var_refs_queue;
1485 function->fixup_var_refs_queue = temp;
1488 /* Variable is local; fix it up now. */
1489 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1493 fixup_var_refs (rtx var, enum machine_mode promoted_mode, int unsignedp,
1494 rtx may_share, htab_t ht)
1497 rtx first_insn = get_insns ();
1498 struct sequence_stack *stack = seq_stack;
1499 tree rtl_exps = rtl_expr_chain;
1501 /* If there's a hash table, it must record all uses of VAR. */
1506 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1511 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1512 stack == 0, may_share);
1514 /* Scan all pending sequences too. */
1515 for (; stack; stack = stack->next)
1517 push_to_full_sequence (stack->first, stack->last);
1518 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1519 stack->next != 0, may_share);
1520 /* Update remembered end of sequence
1521 in case we added an insn at the end. */
1522 stack->last = get_last_insn ();
1526 /* Scan all waiting RTL_EXPRs too. */
1527 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1529 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1530 if (seq != const0_rtx && seq != 0)
1532 push_to_sequence (seq);
1533 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1540 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1541 some part of an insn. Return a struct fixup_replacement whose OLD
1542 value is equal to X. Allocate a new structure if no such entry exists. */
1544 static struct fixup_replacement *
1545 find_fixup_replacement (struct fixup_replacement **replacements, rtx x)
1547 struct fixup_replacement *p;
1549 /* See if we have already replaced this. */
1550 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1555 p = xmalloc (sizeof (struct fixup_replacement));
1558 p->next = *replacements;
1565 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1566 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1567 for the current function. MAY_SHARE is either a MEM that is not
1568 to be unshared or a list of them. */
1571 fixup_var_refs_insns (rtx insn, rtx var, enum machine_mode promoted_mode,
1572 int unsignedp, int toplevel, rtx may_share)
1576 /* fixup_var_refs_insn might modify insn, so save its next
1578 rtx next = NEXT_INSN (insn);
1580 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1581 the three sequences they (potentially) contain, and process
1582 them recursively. The CALL_INSN itself is not interesting. */
1584 if (GET_CODE (insn) == CALL_INSN
1585 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1589 /* Look at the Normal call, sibling call and tail recursion
1590 sequences attached to the CALL_PLACEHOLDER. */
1591 for (i = 0; i < 3; i++)
1593 rtx seq = XEXP (PATTERN (insn), i);
1596 push_to_sequence (seq);
1597 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1599 XEXP (PATTERN (insn), i) = get_insns ();
1605 else if (INSN_P (insn))
1606 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1613 /* Look up the insns which reference VAR in HT and fix them up. Other
1614 arguments are the same as fixup_var_refs_insns.
1616 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1617 because the hash table will point straight to the interesting insn
1618 (inside the CALL_PLACEHOLDER). */
1621 fixup_var_refs_insns_with_hash (htab_t ht, rtx var, enum machine_mode promoted_mode,
1622 int unsignedp, rtx may_share)
1624 struct insns_for_mem_entry tmp;
1625 struct insns_for_mem_entry *ime;
1629 ime = htab_find (ht, &tmp);
1630 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1631 if (INSN_P (XEXP (insn_list, 0)))
1632 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1633 unsignedp, 1, may_share);
1637 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1638 the insn under examination, VAR is the variable to fix up
1639 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1640 TOPLEVEL is nonzero if this is the main insn chain for this
1644 fixup_var_refs_insn (rtx insn, rtx var, enum machine_mode promoted_mode,
1645 int unsignedp, int toplevel, rtx no_share)
1648 rtx set, prev, prev_set;
1651 /* Remember the notes in case we delete the insn. */
1652 note = REG_NOTES (insn);
1654 /* If this is a CLOBBER of VAR, delete it.
1656 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1657 and REG_RETVAL notes too. */
1658 if (GET_CODE (PATTERN (insn)) == CLOBBER
1659 && (XEXP (PATTERN (insn), 0) == var
1660 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1661 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1662 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1664 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1665 /* The REG_LIBCALL note will go away since we are going to
1666 turn INSN into a NOTE, so just delete the
1667 corresponding REG_RETVAL note. */
1668 remove_note (XEXP (note, 0),
1669 find_reg_note (XEXP (note, 0), REG_RETVAL,
1675 /* The insn to load VAR from a home in the arglist
1676 is now a no-op. When we see it, just delete it.
1677 Similarly if this is storing VAR from a register from which
1678 it was loaded in the previous insn. This will occur
1679 when an ADDRESSOF was made for an arglist slot. */
1681 && (set = single_set (insn)) != 0
1682 && SET_DEST (set) == var
1683 /* If this represents the result of an insn group,
1684 don't delete the insn. */
1685 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1686 && (rtx_equal_p (SET_SRC (set), var)
1687 || (GET_CODE (SET_SRC (set)) == REG
1688 && (prev = prev_nonnote_insn (insn)) != 0
1689 && (prev_set = single_set (prev)) != 0
1690 && SET_DEST (prev_set) == SET_SRC (set)
1691 && rtx_equal_p (SET_SRC (prev_set), var))))
1697 struct fixup_replacement *replacements = 0;
1698 rtx next_insn = NEXT_INSN (insn);
1700 if (SMALL_REGISTER_CLASSES)
1702 /* If the insn that copies the results of a CALL_INSN
1703 into a pseudo now references VAR, we have to use an
1704 intermediate pseudo since we want the life of the
1705 return value register to be only a single insn.
1707 If we don't use an intermediate pseudo, such things as
1708 address computations to make the address of VAR valid
1709 if it is not can be placed between the CALL_INSN and INSN.
1711 To make sure this doesn't happen, we record the destination
1712 of the CALL_INSN and see if the next insn uses both that
1715 if (call_dest != 0 && GET_CODE (insn) == INSN
1716 && reg_mentioned_p (var, PATTERN (insn))
1717 && reg_mentioned_p (call_dest, PATTERN (insn)))
1719 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1721 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1723 PATTERN (insn) = replace_rtx (PATTERN (insn),
1727 if (GET_CODE (insn) == CALL_INSN
1728 && GET_CODE (PATTERN (insn)) == SET)
1729 call_dest = SET_DEST (PATTERN (insn));
1730 else if (GET_CODE (insn) == CALL_INSN
1731 && GET_CODE (PATTERN (insn)) == PARALLEL
1732 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1733 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1738 /* See if we have to do anything to INSN now that VAR is in
1739 memory. If it needs to be loaded into a pseudo, use a single
1740 pseudo for the entire insn in case there is a MATCH_DUP
1741 between two operands. We pass a pointer to the head of
1742 a list of struct fixup_replacements. If fixup_var_refs_1
1743 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1744 it will record them in this list.
1746 If it allocated a pseudo for any replacement, we copy into
1749 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1750 &replacements, no_share);
1752 /* If this is last_parm_insn, and any instructions were output
1753 after it to fix it up, then we must set last_parm_insn to
1754 the last such instruction emitted. */
1755 if (insn == last_parm_insn)
1756 last_parm_insn = PREV_INSN (next_insn);
1758 while (replacements)
1760 struct fixup_replacement *next;
1762 if (GET_CODE (replacements->new) == REG)
1767 /* OLD might be a (subreg (mem)). */
1768 if (GET_CODE (replacements->old) == SUBREG)
1770 = fixup_memory_subreg (replacements->old, insn,
1774 = fixup_stack_1 (replacements->old, insn);
1776 insert_before = insn;
1778 /* If we are changing the mode, do a conversion.
1779 This might be wasteful, but combine.c will
1780 eliminate much of the waste. */
1782 if (GET_MODE (replacements->new)
1783 != GET_MODE (replacements->old))
1786 convert_move (replacements->new,
1787 replacements->old, unsignedp);
1792 seq = gen_move_insn (replacements->new,
1795 emit_insn_before (seq, insert_before);
1798 next = replacements->next;
1799 free (replacements);
1800 replacements = next;
1804 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1805 But don't touch other insns referred to by reg-notes;
1806 we will get them elsewhere. */
1809 if (GET_CODE (note) != INSN_LIST)
1811 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1813 note = XEXP (note, 1);
1817 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1818 See if the rtx expression at *LOC in INSN needs to be changed.
1820 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1821 contain a list of original rtx's and replacements. If we find that we need
1822 to modify this insn by replacing a memory reference with a pseudo or by
1823 making a new MEM to implement a SUBREG, we consult that list to see if
1824 we have already chosen a replacement. If none has already been allocated,
1825 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1826 or the SUBREG, as appropriate, to the pseudo. */
1829 fixup_var_refs_1 (rtx var, enum machine_mode promoted_mode, rtx *loc, rtx insn,
1830 struct fixup_replacement **replacements, rtx no_share)
1834 RTX_CODE code = GET_CODE (x);
1837 struct fixup_replacement *replacement;
1842 if (XEXP (x, 0) == var)
1844 /* Prevent sharing of rtl that might lose. */
1845 rtx sub = copy_rtx (XEXP (var, 0));
1847 if (! validate_change (insn, loc, sub, 0))
1849 rtx y = gen_reg_rtx (GET_MODE (sub));
1852 /* We should be able to replace with a register or all is lost.
1853 Note that we can't use validate_change to verify this, since
1854 we're not caring for replacing all dups simultaneously. */
1855 if (! validate_replace_rtx (*loc, y, insn))
1858 /* Careful! First try to recognize a direct move of the
1859 value, mimicking how things are done in gen_reload wrt
1860 PLUS. Consider what happens when insn is a conditional
1861 move instruction and addsi3 clobbers flags. */
1864 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1868 if (recog_memoized (new_insn) < 0)
1870 /* That failed. Fall back on force_operand and hope. */
1873 sub = force_operand (sub, y);
1875 emit_insn (gen_move_insn (y, sub));
1881 /* Don't separate setter from user. */
1882 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1883 insn = PREV_INSN (insn);
1886 emit_insn_before (seq, insn);
1894 /* If we already have a replacement, use it. Otherwise,
1895 try to fix up this address in case it is invalid. */
1897 replacement = find_fixup_replacement (replacements, var);
1898 if (replacement->new)
1900 *loc = replacement->new;
1904 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1906 /* Unless we are forcing memory to register or we changed the mode,
1907 we can leave things the way they are if the insn is valid. */
1909 INSN_CODE (insn) = -1;
1910 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1911 && recog_memoized (insn) >= 0)
1914 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1918 /* If X contains VAR, we need to unshare it here so that we update
1919 each occurrence separately. But all identical MEMs in one insn
1920 must be replaced with the same rtx because of the possibility of
1923 if (reg_mentioned_p (var, x))
1925 replacement = find_fixup_replacement (replacements, x);
1926 if (replacement->new == 0)
1927 replacement->new = copy_most_rtx (x, no_share);
1929 *loc = x = replacement->new;
1930 code = GET_CODE (x);
1947 /* Note that in some cases those types of expressions are altered
1948 by optimize_bit_field, and do not survive to get here. */
1949 if (XEXP (x, 0) == var
1950 || (GET_CODE (XEXP (x, 0)) == SUBREG
1951 && SUBREG_REG (XEXP (x, 0)) == var))
1953 /* Get TEM as a valid MEM in the mode presently in the insn.
1955 We don't worry about the possibility of MATCH_DUP here; it
1956 is highly unlikely and would be tricky to handle. */
1959 if (GET_CODE (tem) == SUBREG)
1961 if (GET_MODE_BITSIZE (GET_MODE (tem))
1962 > GET_MODE_BITSIZE (GET_MODE (var)))
1964 replacement = find_fixup_replacement (replacements, var);
1965 if (replacement->new == 0)
1966 replacement->new = gen_reg_rtx (GET_MODE (var));
1967 SUBREG_REG (tem) = replacement->new;
1969 /* The following code works only if we have a MEM, so we
1970 need to handle the subreg here. We directly substitute
1971 it assuming that a subreg must be OK here. We already
1972 scheduled a replacement to copy the mem into the
1978 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
1981 tem = fixup_stack_1 (tem, insn);
1983 /* Unless we want to load from memory, get TEM into the proper mode
1984 for an extract from memory. This can only be done if the
1985 extract is at a constant position and length. */
1987 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1988 && GET_CODE (XEXP (x, 2)) == CONST_INT
1989 && ! mode_dependent_address_p (XEXP (tem, 0))
1990 && ! MEM_VOLATILE_P (tem))
1992 enum machine_mode wanted_mode = VOIDmode;
1993 enum machine_mode is_mode = GET_MODE (tem);
1994 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
1996 if (GET_CODE (x) == ZERO_EXTRACT)
1998 enum machine_mode new_mode
1999 = mode_for_extraction (EP_extzv, 1);
2000 if (new_mode != MAX_MACHINE_MODE)
2001 wanted_mode = new_mode;
2003 else if (GET_CODE (x) == SIGN_EXTRACT)
2005 enum machine_mode new_mode
2006 = mode_for_extraction (EP_extv, 1);
2007 if (new_mode != MAX_MACHINE_MODE)
2008 wanted_mode = new_mode;
2011 /* If we have a narrower mode, we can do something. */
2012 if (wanted_mode != VOIDmode
2013 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2015 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2016 rtx old_pos = XEXP (x, 2);
2019 /* If the bytes and bits are counted differently, we
2020 must adjust the offset. */
2021 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2022 offset = (GET_MODE_SIZE (is_mode)
2023 - GET_MODE_SIZE (wanted_mode) - offset);
2025 pos %= GET_MODE_BITSIZE (wanted_mode);
2027 newmem = adjust_address_nv (tem, wanted_mode, offset);
2029 /* Make the change and see if the insn remains valid. */
2030 INSN_CODE (insn) = -1;
2031 XEXP (x, 0) = newmem;
2032 XEXP (x, 2) = GEN_INT (pos);
2034 if (recog_memoized (insn) >= 0)
2037 /* Otherwise, restore old position. XEXP (x, 0) will be
2039 XEXP (x, 2) = old_pos;
2043 /* If we get here, the bitfield extract insn can't accept a memory
2044 reference. Copy the input into a register. */
2046 tem1 = gen_reg_rtx (GET_MODE (tem));
2047 emit_insn_before (gen_move_insn (tem1, tem), insn);
2054 if (SUBREG_REG (x) == var)
2056 /* If this is a special SUBREG made because VAR was promoted
2057 from a wider mode, replace it with VAR and call ourself
2058 recursively, this time saying that the object previously
2059 had its current mode (by virtue of the SUBREG). */
2061 if (SUBREG_PROMOTED_VAR_P (x))
2064 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2069 /* If this SUBREG makes VAR wider, it has become a paradoxical
2070 SUBREG with VAR in memory, but these aren't allowed at this
2071 stage of the compilation. So load VAR into a pseudo and take
2072 a SUBREG of that pseudo. */
2073 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2075 replacement = find_fixup_replacement (replacements, var);
2076 if (replacement->new == 0)
2077 replacement->new = gen_reg_rtx (promoted_mode);
2078 SUBREG_REG (x) = replacement->new;
2082 /* See if we have already found a replacement for this SUBREG.
2083 If so, use it. Otherwise, make a MEM and see if the insn
2084 is recognized. If not, or if we should force MEM into a register,
2085 make a pseudo for this SUBREG. */
2086 replacement = find_fixup_replacement (replacements, x);
2087 if (replacement->new)
2089 *loc = replacement->new;
2093 replacement->new = *loc = fixup_memory_subreg (x, insn,
2096 INSN_CODE (insn) = -1;
2097 if (! flag_force_mem && recog_memoized (insn) >= 0)
2100 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2106 /* First do special simplification of bit-field references. */
2107 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2108 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2109 optimize_bit_field (x, insn, 0);
2110 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2111 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2112 optimize_bit_field (x, insn, 0);
2114 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2115 into a register and then store it back out. */
2116 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2117 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2118 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2119 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2120 > GET_MODE_SIZE (GET_MODE (var))))
2122 replacement = find_fixup_replacement (replacements, var);
2123 if (replacement->new == 0)
2124 replacement->new = gen_reg_rtx (GET_MODE (var));
2126 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2127 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2130 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2131 insn into a pseudo and store the low part of the pseudo into VAR. */
2132 if (GET_CODE (SET_DEST (x)) == SUBREG
2133 && SUBREG_REG (SET_DEST (x)) == var
2134 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2135 > GET_MODE_SIZE (GET_MODE (var))))
2137 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2138 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2145 rtx dest = SET_DEST (x);
2146 rtx src = SET_SRC (x);
2147 rtx outerdest = dest;
2149 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2150 || GET_CODE (dest) == SIGN_EXTRACT
2151 || GET_CODE (dest) == ZERO_EXTRACT)
2152 dest = XEXP (dest, 0);
2154 if (GET_CODE (src) == SUBREG)
2155 src = SUBREG_REG (src);
2157 /* If VAR does not appear at the top level of the SET
2158 just scan the lower levels of the tree. */
2160 if (src != var && dest != var)
2163 /* We will need to rerecognize this insn. */
2164 INSN_CODE (insn) = -1;
2166 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2167 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2169 /* Since this case will return, ensure we fixup all the
2171 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2172 insn, replacements, no_share);
2173 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2174 insn, replacements, no_share);
2175 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2176 insn, replacements, no_share);
2178 tem = XEXP (outerdest, 0);
2180 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2181 that may appear inside a ZERO_EXTRACT.
2182 This was legitimate when the MEM was a REG. */
2183 if (GET_CODE (tem) == SUBREG
2184 && SUBREG_REG (tem) == var)
2185 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2187 tem = fixup_stack_1 (tem, insn);
2189 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2190 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2191 && ! mode_dependent_address_p (XEXP (tem, 0))
2192 && ! MEM_VOLATILE_P (tem))
2194 enum machine_mode wanted_mode;
2195 enum machine_mode is_mode = GET_MODE (tem);
2196 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2198 wanted_mode = mode_for_extraction (EP_insv, 0);
2200 /* If we have a narrower mode, we can do something. */
2201 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2203 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2204 rtx old_pos = XEXP (outerdest, 2);
2207 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2208 offset = (GET_MODE_SIZE (is_mode)
2209 - GET_MODE_SIZE (wanted_mode) - offset);
2211 pos %= GET_MODE_BITSIZE (wanted_mode);
2213 newmem = adjust_address_nv (tem, wanted_mode, offset);
2215 /* Make the change and see if the insn remains valid. */
2216 INSN_CODE (insn) = -1;
2217 XEXP (outerdest, 0) = newmem;
2218 XEXP (outerdest, 2) = GEN_INT (pos);
2220 if (recog_memoized (insn) >= 0)
2223 /* Otherwise, restore old position. XEXP (x, 0) will be
2225 XEXP (outerdest, 2) = old_pos;
2229 /* If we get here, the bit-field store doesn't allow memory
2230 or isn't located at a constant position. Load the value into
2231 a register, do the store, and put it back into memory. */
2233 tem1 = gen_reg_rtx (GET_MODE (tem));
2234 emit_insn_before (gen_move_insn (tem1, tem), insn);
2235 emit_insn_after (gen_move_insn (tem, tem1), insn);
2236 XEXP (outerdest, 0) = tem1;
2240 /* STRICT_LOW_PART is a no-op on memory references
2241 and it can cause combinations to be unrecognizable,
2244 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2245 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2247 /* A valid insn to copy VAR into or out of a register
2248 must be left alone, to avoid an infinite loop here.
2249 If the reference to VAR is by a subreg, fix that up,
2250 since SUBREG is not valid for a memref.
2251 Also fix up the address of the stack slot.
2253 Note that we must not try to recognize the insn until
2254 after we know that we have valid addresses and no
2255 (subreg (mem ...) ...) constructs, since these interfere
2256 with determining the validity of the insn. */
2258 if ((SET_SRC (x) == var
2259 || (GET_CODE (SET_SRC (x)) == SUBREG
2260 && SUBREG_REG (SET_SRC (x)) == var))
2261 && (GET_CODE (SET_DEST (x)) == REG
2262 || (GET_CODE (SET_DEST (x)) == SUBREG
2263 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2264 && GET_MODE (var) == promoted_mode
2265 && x == single_set (insn))
2269 if (GET_CODE (SET_SRC (x)) == SUBREG
2270 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2271 > GET_MODE_SIZE (GET_MODE (var))))
2273 /* This (subreg VAR) is now a paradoxical subreg. We need
2274 to replace VAR instead of the subreg. */
2275 replacement = find_fixup_replacement (replacements, var);
2276 if (replacement->new == NULL_RTX)
2277 replacement->new = gen_reg_rtx (GET_MODE (var));
2278 SUBREG_REG (SET_SRC (x)) = replacement->new;
2282 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2283 if (replacement->new)
2284 SET_SRC (x) = replacement->new;
2285 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2286 SET_SRC (x) = replacement->new
2287 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2290 SET_SRC (x) = replacement->new
2291 = fixup_stack_1 (SET_SRC (x), insn);
2294 if (recog_memoized (insn) >= 0)
2297 /* INSN is not valid, but we know that we want to
2298 copy SET_SRC (x) to SET_DEST (x) in some way. So
2299 we generate the move and see whether it requires more
2300 than one insn. If it does, we emit those insns and
2301 delete INSN. Otherwise, we can just replace the pattern
2302 of INSN; we have already verified above that INSN has
2303 no other function that to do X. */
2305 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2306 if (NEXT_INSN (pat) != NULL_RTX)
2308 last = emit_insn_before (pat, insn);
2310 /* INSN might have REG_RETVAL or other important notes, so
2311 we need to store the pattern of the last insn in the
2312 sequence into INSN similarly to the normal case. LAST
2313 should not have REG_NOTES, but we allow them if INSN has
2315 if (REG_NOTES (last) && REG_NOTES (insn))
2317 if (REG_NOTES (last))
2318 REG_NOTES (insn) = REG_NOTES (last);
2319 PATTERN (insn) = PATTERN (last);
2324 PATTERN (insn) = PATTERN (pat);
2329 if ((SET_DEST (x) == var
2330 || (GET_CODE (SET_DEST (x)) == SUBREG
2331 && SUBREG_REG (SET_DEST (x)) == var))
2332 && (GET_CODE (SET_SRC (x)) == REG
2333 || (GET_CODE (SET_SRC (x)) == SUBREG
2334 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2335 && GET_MODE (var) == promoted_mode
2336 && x == single_set (insn))
2340 if (GET_CODE (SET_DEST (x)) == SUBREG)
2341 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2344 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2346 if (recog_memoized (insn) >= 0)
2349 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2350 if (NEXT_INSN (pat) != NULL_RTX)
2352 last = emit_insn_before (pat, insn);
2354 /* INSN might have REG_RETVAL or other important notes, so
2355 we need to store the pattern of the last insn in the
2356 sequence into INSN similarly to the normal case. LAST
2357 should not have REG_NOTES, but we allow them if INSN has
2359 if (REG_NOTES (last) && REG_NOTES (insn))
2361 if (REG_NOTES (last))
2362 REG_NOTES (insn) = REG_NOTES (last);
2363 PATTERN (insn) = PATTERN (last);
2368 PATTERN (insn) = PATTERN (pat);
2373 /* Otherwise, storing into VAR must be handled specially
2374 by storing into a temporary and copying that into VAR
2375 with a new insn after this one. Note that this case
2376 will be used when storing into a promoted scalar since
2377 the insn will now have different modes on the input
2378 and output and hence will be invalid (except for the case
2379 of setting it to a constant, which does not need any
2380 change if it is valid). We generate extra code in that case,
2381 but combine.c will eliminate it. */
2386 rtx fixeddest = SET_DEST (x);
2387 enum machine_mode temp_mode;
2389 /* STRICT_LOW_PART can be discarded, around a MEM. */
2390 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2391 fixeddest = XEXP (fixeddest, 0);
2392 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2393 if (GET_CODE (fixeddest) == SUBREG)
2395 fixeddest = fixup_memory_subreg (fixeddest, insn,
2397 temp_mode = GET_MODE (fixeddest);
2401 fixeddest = fixup_stack_1 (fixeddest, insn);
2402 temp_mode = promoted_mode;
2405 temp = gen_reg_rtx (temp_mode);
2407 emit_insn_after (gen_move_insn (fixeddest,
2408 gen_lowpart (GET_MODE (fixeddest),
2412 SET_DEST (x) = temp;
2420 /* Nothing special about this RTX; fix its operands. */
2422 fmt = GET_RTX_FORMAT (code);
2423 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2426 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2428 else if (fmt[i] == 'E')
2431 for (j = 0; j < XVECLEN (x, i); j++)
2432 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2433 insn, replacements, no_share);
2438 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2439 The REG was placed on the stack, so X now has the form (SUBREG:m1
2442 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2443 must be emitted to compute NEWADDR, put them before INSN.
2445 UNCRITICAL nonzero means accept paradoxical subregs.
2446 This is used for subregs found inside REG_NOTES. */
2449 fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode, int uncritical)
2452 rtx mem = SUBREG_REG (x);
2453 rtx addr = XEXP (mem, 0);
2454 enum machine_mode mode = GET_MODE (x);
2457 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2458 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2461 offset = SUBREG_BYTE (x);
2462 if (BYTES_BIG_ENDIAN)
2463 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2464 the offset so that it points to the right location within the
2466 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2468 if (!flag_force_addr
2469 && memory_address_p (mode, plus_constant (addr, offset)))
2470 /* Shortcut if no insns need be emitted. */
2471 return adjust_address (mem, mode, offset);
2474 result = adjust_address (mem, mode, offset);
2478 emit_insn_before (seq, insn);
2482 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2483 Replace subexpressions of X in place.
2484 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2485 Otherwise return X, with its contents possibly altered.
2487 INSN, PROMOTED_MODE and UNCRITICAL are as for
2488 fixup_memory_subreg. */
2491 walk_fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode,
2501 code = GET_CODE (x);
2503 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2504 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2506 /* Nothing special about this RTX; fix its operands. */
2508 fmt = GET_RTX_FORMAT (code);
2509 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2512 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2513 promoted_mode, uncritical);
2514 else if (fmt[i] == 'E')
2517 for (j = 0; j < XVECLEN (x, i); j++)
2519 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2520 promoted_mode, uncritical);
2526 /* For each memory ref within X, if it refers to a stack slot
2527 with an out of range displacement, put the address in a temp register
2528 (emitting new insns before INSN to load these registers)
2529 and alter the memory ref to use that register.
2530 Replace each such MEM rtx with a copy, to avoid clobberage. */
2533 fixup_stack_1 (rtx x, rtx insn)
2536 RTX_CODE code = GET_CODE (x);
2541 rtx ad = XEXP (x, 0);
2542 /* If we have address of a stack slot but it's not valid
2543 (displacement is too large), compute the sum in a register. */
2544 if (GET_CODE (ad) == PLUS
2545 && GET_CODE (XEXP (ad, 0)) == REG
2546 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2547 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2548 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2549 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2550 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2552 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2553 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2554 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2555 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2558 if (memory_address_p (GET_MODE (x), ad))
2562 temp = copy_to_reg (ad);
2565 emit_insn_before (seq, insn);
2566 return replace_equiv_address (x, temp);
2571 fmt = GET_RTX_FORMAT (code);
2572 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2575 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2576 else if (fmt[i] == 'E')
2579 for (j = 0; j < XVECLEN (x, i); j++)
2580 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2586 /* Optimization: a bit-field instruction whose field
2587 happens to be a byte or halfword in memory
2588 can be changed to a move instruction.
2590 We call here when INSN is an insn to examine or store into a bit-field.
2591 BODY is the SET-rtx to be altered.
2593 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2594 (Currently this is called only from function.c, and EQUIV_MEM
2598 optimize_bit_field (rtx body, rtx insn, rtx *equiv_mem)
2603 enum machine_mode mode;
2605 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2606 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2607 bitfield = SET_DEST (body), destflag = 1;
2609 bitfield = SET_SRC (body), destflag = 0;
2611 /* First check that the field being stored has constant size and position
2612 and is in fact a byte or halfword suitably aligned. */
2614 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2615 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2616 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2618 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2622 /* Now check that the containing word is memory, not a register,
2623 and that it is safe to change the machine mode. */
2625 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2626 memref = XEXP (bitfield, 0);
2627 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2629 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2630 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2631 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2632 memref = SUBREG_REG (XEXP (bitfield, 0));
2633 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2635 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2636 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2639 && ! mode_dependent_address_p (XEXP (memref, 0))
2640 && ! MEM_VOLATILE_P (memref))
2642 /* Now adjust the address, first for any subreg'ing
2643 that we are now getting rid of,
2644 and then for which byte of the word is wanted. */
2646 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2649 /* Adjust OFFSET to count bits from low-address byte. */
2650 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2651 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2652 - offset - INTVAL (XEXP (bitfield, 1)));
2654 /* Adjust OFFSET to count bytes from low-address byte. */
2655 offset /= BITS_PER_UNIT;
2656 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2658 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2659 / UNITS_PER_WORD) * UNITS_PER_WORD;
2660 if (BYTES_BIG_ENDIAN)
2661 offset -= (MIN (UNITS_PER_WORD,
2662 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2663 - MIN (UNITS_PER_WORD,
2664 GET_MODE_SIZE (GET_MODE (memref))));
2668 memref = adjust_address (memref, mode, offset);
2669 insns = get_insns ();
2671 emit_insn_before (insns, insn);
2673 /* Store this memory reference where
2674 we found the bit field reference. */
2678 validate_change (insn, &SET_DEST (body), memref, 1);
2679 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2681 rtx src = SET_SRC (body);
2682 while (GET_CODE (src) == SUBREG
2683 && SUBREG_BYTE (src) == 0)
2684 src = SUBREG_REG (src);
2685 if (GET_MODE (src) != GET_MODE (memref))
2686 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2687 validate_change (insn, &SET_SRC (body), src, 1);
2689 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2690 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2691 /* This shouldn't happen because anything that didn't have
2692 one of these modes should have got converted explicitly
2693 and then referenced through a subreg.
2694 This is so because the original bit-field was
2695 handled by agg_mode and so its tree structure had
2696 the same mode that memref now has. */
2701 rtx dest = SET_DEST (body);
2703 while (GET_CODE (dest) == SUBREG
2704 && SUBREG_BYTE (dest) == 0
2705 && (GET_MODE_CLASS (GET_MODE (dest))
2706 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2707 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2709 dest = SUBREG_REG (dest);
2711 validate_change (insn, &SET_DEST (body), dest, 1);
2713 if (GET_MODE (dest) == GET_MODE (memref))
2714 validate_change (insn, &SET_SRC (body), memref, 1);
2717 /* Convert the mem ref to the destination mode. */
2718 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2721 convert_move (newreg, memref,
2722 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2726 validate_change (insn, &SET_SRC (body), newreg, 1);
2730 /* See if we can convert this extraction or insertion into
2731 a simple move insn. We might not be able to do so if this
2732 was, for example, part of a PARALLEL.
2734 If we succeed, write out any needed conversions. If we fail,
2735 it is hard to guess why we failed, so don't do anything
2736 special; just let the optimization be suppressed. */
2738 if (apply_change_group () && seq)
2739 emit_insn_before (seq, insn);
2744 /* These routines are responsible for converting virtual register references
2745 to the actual hard register references once RTL generation is complete.
2747 The following four variables are used for communication between the
2748 routines. They contain the offsets of the virtual registers from their
2749 respective hard registers. */
2751 static int in_arg_offset;
2752 static int var_offset;
2753 static int dynamic_offset;
2754 static int out_arg_offset;
2755 static int cfa_offset;
2757 /* In most machines, the stack pointer register is equivalent to the bottom
2760 #ifndef STACK_POINTER_OFFSET
2761 #define STACK_POINTER_OFFSET 0
2764 /* If not defined, pick an appropriate default for the offset of dynamically
2765 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2766 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2768 #ifndef STACK_DYNAMIC_OFFSET
2770 /* The bottom of the stack points to the actual arguments. If
2771 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2772 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2773 stack space for register parameters is not pushed by the caller, but
2774 rather part of the fixed stack areas and hence not included in
2775 `current_function_outgoing_args_size'. Nevertheless, we must allow
2776 for it when allocating stack dynamic objects. */
2778 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2779 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2780 ((ACCUMULATE_OUTGOING_ARGS \
2781 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2782 + (STACK_POINTER_OFFSET)) \
2785 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2786 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2787 + (STACK_POINTER_OFFSET))
2791 /* On most machines, the CFA coincides with the first incoming parm. */
2793 #ifndef ARG_POINTER_CFA_OFFSET
2794 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2797 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2798 had its address taken. DECL is the decl or SAVE_EXPR for the
2799 object stored in the register, for later use if we do need to force
2800 REG into the stack. REG is overwritten by the MEM like in
2801 put_reg_into_stack. RESCAN is true if previously emitted
2802 instructions must be rescanned and modified now that the REG has
2803 been transformed. */
2806 gen_mem_addressof (rtx reg, tree decl, int rescan)
2808 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2811 /* Calculate this before we start messing with decl's RTL. */
2812 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2814 /* If the original REG was a user-variable, then so is the REG whose
2815 address is being taken. Likewise for unchanging. */
2816 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2817 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2819 PUT_CODE (reg, MEM);
2820 MEM_ATTRS (reg) = 0;
2825 tree type = TREE_TYPE (decl);
2826 enum machine_mode decl_mode
2827 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2828 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2829 : DECL_RTL_IF_SET (decl));
2831 PUT_MODE (reg, decl_mode);
2833 /* Clear DECL_RTL momentarily so functions below will work
2834 properly, then set it again. */
2835 if (DECL_P (decl) && decl_rtl == reg)
2836 SET_DECL_RTL (decl, 0);
2838 set_mem_attributes (reg, decl, 1);
2839 set_mem_alias_set (reg, set);
2841 if (DECL_P (decl) && decl_rtl == reg)
2842 SET_DECL_RTL (decl, reg);
2845 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0)))
2846 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2849 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2854 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2857 flush_addressof (tree decl)
2859 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2860 && DECL_RTL (decl) != 0
2861 && GET_CODE (DECL_RTL (decl)) == MEM
2862 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2863 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2864 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2867 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2870 put_addressof_into_stack (rtx r, htab_t ht)
2873 int volatile_p, used_p;
2875 rtx reg = XEXP (r, 0);
2877 if (GET_CODE (reg) != REG)
2880 decl = ADDRESSOF_DECL (r);
2883 type = TREE_TYPE (decl);
2884 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2885 && TREE_THIS_VOLATILE (decl));
2886 used_p = (TREE_USED (decl)
2887 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2896 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2897 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2900 /* List of replacements made below in purge_addressof_1 when creating
2901 bitfield insertions. */
2902 static rtx purge_bitfield_addressof_replacements;
2904 /* List of replacements made below in purge_addressof_1 for patterns
2905 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2906 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2907 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2908 enough in complex cases, e.g. when some field values can be
2909 extracted by usage MEM with narrower mode. */
2910 static rtx purge_addressof_replacements;
2912 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2913 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2914 the stack. If the function returns FALSE then the replacement could not
2915 be made. If MAY_POSTPONE is true and we would not put the addressof
2916 to stack, postpone processing of the insn. */
2919 purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
2928 /* Re-start here to avoid recursion in common cases. */
2935 code = GET_CODE (x);
2937 /* If we don't return in any of the cases below, we will recurse inside
2938 the RTX, which will normally result in any ADDRESSOF being forced into
2942 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1,
2944 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0,
2948 else if (code == ADDRESSOF)
2952 if (GET_CODE (XEXP (x, 0)) != MEM)
2953 put_addressof_into_stack (x, ht);
2955 /* We must create a copy of the rtx because it was created by
2956 overwriting a REG rtx which is always shared. */
2957 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2958 if (validate_change (insn, loc, sub, 0)
2959 || validate_replace_rtx (x, sub, insn))
2964 /* If SUB is a hard or virtual register, try it as a pseudo-register.
2965 Otherwise, perhaps SUB is an expression, so generate code to compute
2967 if (GET_CODE (sub) == REG && REGNO (sub) <= LAST_VIRTUAL_REGISTER)
2968 sub = copy_to_reg (sub);
2970 sub = force_operand (sub, NULL_RTX);
2972 if (! validate_change (insn, loc, sub, 0)
2973 && ! validate_replace_rtx (x, sub, insn))
2976 insns = get_insns ();
2978 emit_insn_before (insns, insn);
2982 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2984 rtx sub = XEXP (XEXP (x, 0), 0);
2986 if (GET_CODE (sub) == MEM)
2987 sub = adjust_address_nv (sub, GET_MODE (x), 0);
2988 else if (GET_CODE (sub) == REG
2989 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
2991 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
2993 int size_x, size_sub;
2997 /* Postpone for now, so that we do not emit bitfield arithmetics
2998 unless there is some benefit from it. */
2999 if (!postponed_insns || XEXP (postponed_insns, 0) != insn)
3000 postponed_insns = alloc_INSN_LIST (insn, postponed_insns);
3006 /* When processing REG_NOTES look at the list of
3007 replacements done on the insn to find the register that X
3011 for (tem = purge_bitfield_addressof_replacements;
3013 tem = XEXP (XEXP (tem, 1), 1))
3014 if (rtx_equal_p (x, XEXP (tem, 0)))
3016 *loc = XEXP (XEXP (tem, 1), 0);
3020 /* See comment for purge_addressof_replacements. */
3021 for (tem = purge_addressof_replacements;
3023 tem = XEXP (XEXP (tem, 1), 1))
3024 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3026 rtx z = XEXP (XEXP (tem, 1), 0);
3028 if (GET_MODE (x) == GET_MODE (z)
3029 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3030 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3033 /* It can happen that the note may speak of things
3034 in a wider (or just different) mode than the
3035 code did. This is especially true of
3038 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3041 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3042 && (GET_MODE_SIZE (GET_MODE (x))
3043 > GET_MODE_SIZE (GET_MODE (z))))
3045 /* This can occur as a result in invalid
3046 pointer casts, e.g. float f; ...
3047 *(long long int *)&f.
3048 ??? We could emit a warning here, but
3049 without a line number that wouldn't be
3051 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3054 z = gen_lowpart (GET_MODE (x), z);
3060 /* When we are processing the REG_NOTES of the last instruction
3061 of a libcall, there will be typically no replacements
3062 for that insn; the replacements happened before, piecemeal
3063 fashion. OTOH we are not interested in the details of
3064 this for the REG_EQUAL note, we want to know the big picture,
3065 which can be succinctly described with a simple SUBREG.
3066 Note that removing the REG_EQUAL note is not an option
3067 on the last insn of a libcall, so we must do a replacement. */
3068 if (! purge_addressof_replacements
3069 && ! purge_bitfield_addressof_replacements)
3071 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
3073 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
3074 [0 S8 A32]), which can be expressed with a simple
3076 if ((GET_MODE_SIZE (GET_MODE (x))
3077 == GET_MODE_SIZE (GET_MODE (sub)))
3078 /* Again, invalid pointer casts (as in
3079 compile/990203-1.c) can require paradoxical
3081 || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3082 && (GET_MODE_SIZE (GET_MODE (x))
3083 > GET_MODE_SIZE (GET_MODE (sub)))))
3085 *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
3088 /* ??? Are there other cases we should handle? */
3090 /* Sometimes we may not be able to find the replacement. For
3091 example when the original insn was a MEM in a wider mode,
3092 and the note is part of a sign extension of a narrowed
3093 version of that MEM. Gcc testcase compile/990829-1.c can
3094 generate an example of this situation. Rather than complain
3095 we return false, which will prompt our caller to remove the
3100 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3101 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3103 /* Do not frob unchanging MEMs. If a later reference forces the
3104 pseudo to the stack, we can wind up with multiple writes to
3105 an unchanging memory, which is invalid. */
3106 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3109 /* Don't even consider working with paradoxical subregs,
3110 or the moral equivalent seen here. */
3111 else if (size_x <= size_sub
3112 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3114 /* Do a bitfield insertion to mirror what would happen
3121 rtx p = PREV_INSN (insn);
3124 val = gen_reg_rtx (GET_MODE (x));
3125 if (! validate_change (insn, loc, val, 0))
3127 /* Discard the current sequence and put the
3128 ADDRESSOF on stack. */
3134 emit_insn_before (seq, insn);
3135 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3139 store_bit_field (sub, size_x, 0, GET_MODE (x),
3140 val, GET_MODE_SIZE (GET_MODE (sub)));
3142 /* Make sure to unshare any shared rtl that store_bit_field
3143 might have created. */
3144 unshare_all_rtl_again (get_insns ());
3148 p = emit_insn_after (seq, insn);
3149 if (NEXT_INSN (insn))
3150 compute_insns_for_mem (NEXT_INSN (insn),
3151 p ? NEXT_INSN (p) : NULL_RTX,
3156 rtx p = PREV_INSN (insn);
3159 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3160 GET_MODE (x), GET_MODE (x),
3161 GET_MODE_SIZE (GET_MODE (sub)));
3163 if (! validate_change (insn, loc, val, 0))
3165 /* Discard the current sequence and put the
3166 ADDRESSOF on stack. */
3173 emit_insn_before (seq, insn);
3174 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3178 /* Remember the replacement so that the same one can be done
3179 on the REG_NOTES. */
3180 purge_bitfield_addressof_replacements
3181 = gen_rtx_EXPR_LIST (VOIDmode, x,
3184 purge_bitfield_addressof_replacements));
3186 /* We replaced with a reg -- all done. */
3191 else if (validate_change (insn, loc, sub, 0))
3193 /* Remember the replacement so that the same one can be done
3194 on the REG_NOTES. */
3195 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3199 for (tem = purge_addressof_replacements;
3201 tem = XEXP (XEXP (tem, 1), 1))
3202 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3204 XEXP (XEXP (tem, 1), 0) = sub;
3207 purge_addressof_replacements
3208 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3209 gen_rtx_EXPR_LIST (VOIDmode, sub,
3210 purge_addressof_replacements));
3218 /* Scan all subexpressions. */
3219 fmt = GET_RTX_FORMAT (code);
3220 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3223 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0,
3225 else if (*fmt == 'E')
3226 for (j = 0; j < XVECLEN (x, i); j++)
3227 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0,
3234 /* Return a hash value for K, a REG. */
3237 insns_for_mem_hash (const void *k)
3239 /* Use the address of the key for the hash value. */
3240 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3241 return htab_hash_pointer (m->key);
3244 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3247 insns_for_mem_comp (const void *k1, const void *k2)
3249 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3250 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3251 return m1->key == m2->key;
3254 struct insns_for_mem_walk_info
3256 /* The hash table that we are using to record which INSNs use which
3260 /* The INSN we are currently processing. */
3263 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3264 to find the insns that use the REGs in the ADDRESSOFs. */
3268 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3269 that might be used in an ADDRESSOF expression, record this INSN in
3270 the hash table given by DATA (which is really a pointer to an
3271 insns_for_mem_walk_info structure). */
3274 insns_for_mem_walk (rtx *r, void *data)
3276 struct insns_for_mem_walk_info *ifmwi
3277 = (struct insns_for_mem_walk_info *) data;
3278 struct insns_for_mem_entry tmp;
3279 tmp.insns = NULL_RTX;
3281 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3282 && GET_CODE (XEXP (*r, 0)) == REG)
3285 tmp.key = XEXP (*r, 0);
3286 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3289 *e = ggc_alloc (sizeof (tmp));
3290 memcpy (*e, &tmp, sizeof (tmp));
3293 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3295 struct insns_for_mem_entry *ifme;
3297 ifme = htab_find (ifmwi->ht, &tmp);
3299 /* If we have not already recorded this INSN, do so now. Since
3300 we process the INSNs in order, we know that if we have
3301 recorded it it must be at the front of the list. */
3302 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3303 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3310 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3311 which REGs in HT. */
3314 compute_insns_for_mem (rtx insns, rtx last_insn, htab_t ht)
3317 struct insns_for_mem_walk_info ifmwi;
3320 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3321 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3325 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3329 /* Helper function for purge_addressof called through for_each_rtx.
3330 Returns true iff the rtl is an ADDRESSOF. */
3333 is_addressof (rtx *rtl, void *data ATTRIBUTE_UNUSED)
3335 return GET_CODE (*rtl) == ADDRESSOF;
3338 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3339 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3343 purge_addressof (rtx insns)
3348 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3349 requires a fixup pass over the instruction stream to correct
3350 INSNs that depended on the REG being a REG, and not a MEM. But,
3351 these fixup passes are slow. Furthermore, most MEMs are not
3352 mentioned in very many instructions. So, we speed up the process
3353 by pre-calculating which REGs occur in which INSNs; that allows
3354 us to perform the fixup passes much more quickly. */
3355 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3356 compute_insns_for_mem (insns, NULL_RTX, ht);
3358 postponed_insns = NULL;
3360 for (insn = insns; insn; insn = NEXT_INSN (insn))
3363 if (! purge_addressof_1 (&PATTERN (insn), insn,
3364 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht))
3365 /* If we could not replace the ADDRESSOFs in the insn,
3366 something is wrong. */
3369 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht))
3371 /* If we could not replace the ADDRESSOFs in the insn's notes,
3372 we can just remove the offending notes instead. */
3375 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3377 /* If we find a REG_RETVAL note then the insn is a libcall.
3378 Such insns must have REG_EQUAL notes as well, in order
3379 for later passes of the compiler to work. So it is not
3380 safe to delete the notes here, and instead we abort. */
3381 if (REG_NOTE_KIND (note) == REG_RETVAL)
3383 if (for_each_rtx (¬e, is_addressof, NULL))
3384 remove_note (insn, note);
3389 /* Process the postponed insns. */
3390 while (postponed_insns)
3392 insn = XEXP (postponed_insns, 0);
3393 tmp = postponed_insns;
3394 postponed_insns = XEXP (postponed_insns, 1);
3395 free_INSN_LIST_node (tmp);
3397 if (! purge_addressof_1 (&PATTERN (insn), insn,
3398 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht))
3403 purge_bitfield_addressof_replacements = 0;
3404 purge_addressof_replacements = 0;
3406 /* REGs are shared. purge_addressof will destructively replace a REG
3407 with a MEM, which creates shared MEMs.
3409 Unfortunately, the children of put_reg_into_stack assume that MEMs
3410 referring to the same stack slot are shared (fixup_var_refs and
3411 the associated hash table code).
3413 So, we have to do another unsharing pass after we have flushed any
3414 REGs that had their address taken into the stack.
3416 It may be worth tracking whether or not we converted any REGs into
3417 MEMs to avoid this overhead when it is not needed. */
3418 unshare_all_rtl_again (get_insns ());
3421 /* Convert a SET of a hard subreg to a set of the appropriate hard
3422 register. A subroutine of purge_hard_subreg_sets. */
3425 purge_single_hard_subreg_set (rtx pattern)
3427 rtx reg = SET_DEST (pattern);
3428 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3431 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3432 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3434 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3435 GET_MODE (SUBREG_REG (reg)),
3438 reg = SUBREG_REG (reg);
3442 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3444 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3445 SET_DEST (pattern) = reg;
3449 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3450 only such SETs that we expect to see are those left in because
3451 integrate can't handle sets of parts of a return value register.
3453 We don't use alter_subreg because we only want to eliminate subregs
3454 of hard registers. */
3457 purge_hard_subreg_sets (rtx insn)
3459 for (; insn; insn = NEXT_INSN (insn))
3463 rtx pattern = PATTERN (insn);
3464 switch (GET_CODE (pattern))
3467 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3468 purge_single_hard_subreg_set (pattern);
3473 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3475 rtx inner_pattern = XVECEXP (pattern, 0, j);
3476 if (GET_CODE (inner_pattern) == SET
3477 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3478 purge_single_hard_subreg_set (inner_pattern);
3489 /* Pass through the INSNS of function FNDECL and convert virtual register
3490 references to hard register references. */
3493 instantiate_virtual_regs (tree fndecl, rtx insns)
3498 /* Compute the offsets to use for this function. */
3499 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3500 var_offset = STARTING_FRAME_OFFSET;
3501 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3502 out_arg_offset = STACK_POINTER_OFFSET;
3503 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3505 /* Scan all variables and parameters of this function. For each that is
3506 in memory, instantiate all virtual registers if the result is a valid
3507 address. If not, we do it later. That will handle most uses of virtual
3508 regs on many machines. */
3509 instantiate_decls (fndecl, 1);
3511 /* Initialize recognition, indicating that volatile is OK. */
3514 /* Scan through all the insns, instantiating every virtual register still
3516 for (insn = insns; insn; insn = NEXT_INSN (insn))
3517 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3518 || GET_CODE (insn) == CALL_INSN)
3520 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3521 if (INSN_DELETED_P (insn))
3523 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3524 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3525 if (GET_CODE (insn) == CALL_INSN)
3526 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3529 /* Past this point all ASM statements should match. Verify that
3530 to avoid failures later in the compilation process. */
3531 if (asm_noperands (PATTERN (insn)) >= 0
3532 && ! check_asm_operands (PATTERN (insn)))
3533 instantiate_virtual_regs_lossage (insn);
3536 /* Instantiate the stack slots for the parm registers, for later use in
3537 addressof elimination. */
3538 for (i = 0; i < max_parm_reg; ++i)
3539 if (parm_reg_stack_loc[i])
3540 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3542 /* Now instantiate the remaining register equivalences for debugging info.
3543 These will not be valid addresses. */
3544 instantiate_decls (fndecl, 0);
3546 /* Indicate that, from now on, assign_stack_local should use
3547 frame_pointer_rtx. */
3548 virtuals_instantiated = 1;
3551 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3552 all virtual registers in their DECL_RTL's.
3554 If VALID_ONLY, do this only if the resulting address is still valid.
3555 Otherwise, always do it. */
3558 instantiate_decls (tree fndecl, int valid_only)
3562 /* Process all parameters of the function. */
3563 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3565 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3566 HOST_WIDE_INT size_rtl;
3568 instantiate_decl (DECL_RTL (decl), size, valid_only);
3570 /* If the parameter was promoted, then the incoming RTL mode may be
3571 larger than the declared type size. We must use the larger of
3573 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3574 size = MAX (size_rtl, size);
3575 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3578 /* Now process all variables defined in the function or its subblocks. */
3579 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3582 /* Subroutine of instantiate_decls: Process all decls in the given
3583 BLOCK node and all its subblocks. */
3586 instantiate_decls_1 (tree let, int valid_only)
3590 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3591 if (DECL_RTL_SET_P (t))
3592 instantiate_decl (DECL_RTL (t),
3593 int_size_in_bytes (TREE_TYPE (t)),
3596 /* Process all subblocks. */
3597 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3598 instantiate_decls_1 (t, valid_only);
3601 /* Subroutine of the preceding procedures: Given RTL representing a
3602 decl and the size of the object, do any instantiation required.
3604 If VALID_ONLY is nonzero, it means that the RTL should only be
3605 changed if the new address is valid. */
3608 instantiate_decl (rtx x, HOST_WIDE_INT size, int valid_only)
3610 enum machine_mode mode;
3613 /* If this is not a MEM, no need to do anything. Similarly if the
3614 address is a constant or a register that is not a virtual register. */
3616 if (x == 0 || GET_CODE (x) != MEM)
3620 if (CONSTANT_P (addr)
3621 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3622 || (GET_CODE (addr) == REG
3623 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3624 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3627 /* If we should only do this if the address is valid, copy the address.
3628 We need to do this so we can undo any changes that might make the
3629 address invalid. This copy is unfortunate, but probably can't be
3633 addr = copy_rtx (addr);
3635 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3637 if (valid_only && size >= 0)
3639 unsigned HOST_WIDE_INT decl_size = size;
3641 /* Now verify that the resulting address is valid for every integer or
3642 floating-point mode up to and including SIZE bytes long. We do this
3643 since the object might be accessed in any mode and frame addresses
3646 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3647 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3648 mode = GET_MODE_WIDER_MODE (mode))
3649 if (! memory_address_p (mode, addr))
3652 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3653 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3654 mode = GET_MODE_WIDER_MODE (mode))
3655 if (! memory_address_p (mode, addr))
3659 /* Put back the address now that we have updated it and we either know
3660 it is valid or we don't care whether it is valid. */
3665 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3666 is a virtual register, return the equivalent hard register and set the
3667 offset indirectly through the pointer. Otherwise, return 0. */
3670 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
3673 HOST_WIDE_INT offset;
3675 if (x == virtual_incoming_args_rtx)
3676 new = arg_pointer_rtx, offset = in_arg_offset;
3677 else if (x == virtual_stack_vars_rtx)
3678 new = frame_pointer_rtx, offset = var_offset;
3679 else if (x == virtual_stack_dynamic_rtx)
3680 new = stack_pointer_rtx, offset = dynamic_offset;
3681 else if (x == virtual_outgoing_args_rtx)
3682 new = stack_pointer_rtx, offset = out_arg_offset;
3683 else if (x == virtual_cfa_rtx)
3684 new = arg_pointer_rtx, offset = cfa_offset;
3693 /* Called when instantiate_virtual_regs has failed to update the instruction.
3694 Usually this means that non-matching instruction has been emit, however for
3695 asm statements it may be the problem in the constraints. */
3697 instantiate_virtual_regs_lossage (rtx insn)
3699 if (asm_noperands (PATTERN (insn)) >= 0)
3701 error_for_asm (insn, "impossible constraint in `asm'");
3707 /* Given a pointer to a piece of rtx and an optional pointer to the
3708 containing object, instantiate any virtual registers present in it.
3710 If EXTRA_INSNS, we always do the replacement and generate
3711 any extra insns before OBJECT. If it zero, we do nothing if replacement
3714 Return 1 if we either had nothing to do or if we were able to do the
3715 needed replacement. Return 0 otherwise; we only return zero if
3716 EXTRA_INSNS is zero.
3718 We first try some simple transformations to avoid the creation of extra
3722 instantiate_virtual_regs_1 (rtx *loc, rtx object, int extra_insns)
3727 HOST_WIDE_INT offset = 0;
3733 /* Re-start here to avoid recursion in common cases. */
3740 /* We may have detected and deleted invalid asm statements. */
3741 if (object && INSN_P (object) && INSN_DELETED_P (object))
3744 code = GET_CODE (x);
3746 /* Check for some special cases. */
3764 /* We are allowed to set the virtual registers. This means that
3765 the actual register should receive the source minus the
3766 appropriate offset. This is used, for example, in the handling
3767 of non-local gotos. */
3768 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3770 rtx src = SET_SRC (x);
3772 /* We are setting the register, not using it, so the relevant
3773 offset is the negative of the offset to use were we using
3776 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3778 /* The only valid sources here are PLUS or REG. Just do
3779 the simplest possible thing to handle them. */
3780 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3782 instantiate_virtual_regs_lossage (object);
3787 if (GET_CODE (src) != REG)
3788 temp = force_operand (src, NULL_RTX);
3791 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3795 emit_insn_before (seq, object);
3798 if (! validate_change (object, &SET_SRC (x), temp, 0)
3800 instantiate_virtual_regs_lossage (object);
3805 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3810 /* Handle special case of virtual register plus constant. */
3811 if (CONSTANT_P (XEXP (x, 1)))
3813 rtx old, new_offset;
3815 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3816 if (GET_CODE (XEXP (x, 0)) == PLUS)
3818 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3820 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3822 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3831 #ifdef POINTERS_EXTEND_UNSIGNED
3832 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3833 we can commute the PLUS and SUBREG because pointers into the
3834 frame are well-behaved. */
3835 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3836 && GET_CODE (XEXP (x, 1)) == CONST_INT
3838 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3840 && validate_change (object, loc,
3841 plus_constant (gen_lowpart (ptr_mode,
3844 + INTVAL (XEXP (x, 1))),
3848 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3850 /* We know the second operand is a constant. Unless the
3851 first operand is a REG (which has been already checked),
3852 it needs to be checked. */
3853 if (GET_CODE (XEXP (x, 0)) != REG)
3861 new_offset = plus_constant (XEXP (x, 1), offset);
3863 /* If the new constant is zero, try to replace the sum with just
3865 if (new_offset == const0_rtx
3866 && validate_change (object, loc, new, 0))
3869 /* Next try to replace the register and new offset.
3870 There are two changes to validate here and we can't assume that
3871 in the case of old offset equals new just changing the register
3872 will yield a valid insn. In the interests of a little efficiency,
3873 however, we only call validate change once (we don't queue up the
3874 changes and then call apply_change_group). */
3878 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3879 : (XEXP (x, 0) = new,
3880 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3888 /* Otherwise copy the new constant into a register and replace
3889 constant with that register. */
3890 temp = gen_reg_rtx (Pmode);
3892 if (validate_change (object, &XEXP (x, 1), temp, 0))
3893 emit_insn_before (gen_move_insn (temp, new_offset), object);
3896 /* If that didn't work, replace this expression with a
3897 register containing the sum. */
3900 new = gen_rtx_PLUS (Pmode, new, new_offset);
3903 temp = force_operand (new, NULL_RTX);
3907 emit_insn_before (seq, object);
3908 if (! validate_change (object, loc, temp, 0)
3909 && ! validate_replace_rtx (x, temp, object))
3911 instantiate_virtual_regs_lossage (object);
3920 /* Fall through to generic two-operand expression case. */
3926 case DIV: case UDIV:
3927 case MOD: case UMOD:
3928 case AND: case IOR: case XOR:
3929 case ROTATERT: case ROTATE:
3930 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3932 case GE: case GT: case GEU: case GTU:
3933 case LE: case LT: case LEU: case LTU:
3934 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3935 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3940 /* Most cases of MEM that convert to valid addresses have already been
3941 handled by our scan of decls. The only special handling we
3942 need here is to make a copy of the rtx to ensure it isn't being
3943 shared if we have to change it to a pseudo.
3945 If the rtx is a simple reference to an address via a virtual register,
3946 it can potentially be shared. In such cases, first try to make it
3947 a valid address, which can also be shared. Otherwise, copy it and
3950 First check for common cases that need no processing. These are
3951 usually due to instantiation already being done on a previous instance
3955 if (CONSTANT_ADDRESS_P (temp)
3956 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3957 || temp == arg_pointer_rtx
3959 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3960 || temp == hard_frame_pointer_rtx
3962 || temp == frame_pointer_rtx)
3965 if (GET_CODE (temp) == PLUS
3966 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3967 && (XEXP (temp, 0) == frame_pointer_rtx
3968 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3969 || XEXP (temp, 0) == hard_frame_pointer_rtx
3971 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3972 || XEXP (temp, 0) == arg_pointer_rtx
3977 if (temp == virtual_stack_vars_rtx
3978 || temp == virtual_incoming_args_rtx
3979 || (GET_CODE (temp) == PLUS
3980 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3981 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3982 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3984 /* This MEM may be shared. If the substitution can be done without
3985 the need to generate new pseudos, we want to do it in place
3986 so all copies of the shared rtx benefit. The call below will
3987 only make substitutions if the resulting address is still
3990 Note that we cannot pass X as the object in the recursive call
3991 since the insn being processed may not allow all valid
3992 addresses. However, if we were not passed on object, we can
3993 only modify X without copying it if X will have a valid
3996 ??? Also note that this can still lose if OBJECT is an insn that
3997 has less restrictions on an address that some other insn.
3998 In that case, we will modify the shared address. This case
3999 doesn't seem very likely, though. One case where this could
4000 happen is in the case of a USE or CLOBBER reference, but we
4001 take care of that below. */
4003 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4004 object ? object : x, 0))
4007 /* Otherwise make a copy and process that copy. We copy the entire
4008 RTL expression since it might be a PLUS which could also be
4010 *loc = x = copy_rtx (x);
4013 /* Fall through to generic unary operation case. */
4016 case STRICT_LOW_PART:
4018 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4019 case SIGN_EXTEND: case ZERO_EXTEND:
4020 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4021 case FLOAT: case FIX:
4022 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4027 case POPCOUNT: case PARITY:
4028 /* These case either have just one operand or we know that we need not
4029 check the rest of the operands. */
4035 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4036 go ahead and make the invalid one, but do it to a copy. For a REG,
4037 just make the recursive call, since there's no chance of a problem. */
4039 if ((GET_CODE (XEXP (x, 0)) == MEM
4040 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4042 || (GET_CODE (XEXP (x, 0)) == REG
4043 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4046 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4051 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4052 in front of this insn and substitute the temporary. */
4053 if ((new = instantiate_new_reg (x, &offset)) != 0)
4055 temp = plus_constant (new, offset);
4056 if (!validate_change (object, loc, temp, 0))
4062 temp = force_operand (temp, NULL_RTX);
4066 emit_insn_before (seq, object);
4067 if (! validate_change (object, loc, temp, 0)
4068 && ! validate_replace_rtx (x, temp, object))
4069 instantiate_virtual_regs_lossage (object);
4076 if (GET_CODE (XEXP (x, 0)) == REG)
4079 else if (GET_CODE (XEXP (x, 0)) == MEM)
4081 /* If we have a (addressof (mem ..)), do any instantiation inside
4082 since we know we'll be making the inside valid when we finally
4083 remove the ADDRESSOF. */
4084 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4093 /* Scan all subexpressions. */
4094 fmt = GET_RTX_FORMAT (code);
4095 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4098 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4101 else if (*fmt == 'E')
4102 for (j = 0; j < XVECLEN (x, i); j++)
4103 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4110 /* Optimization: assuming this function does not receive nonlocal gotos,
4111 delete the handlers for such, as well as the insns to establish
4112 and disestablish them. */
4115 delete_handlers (void)
4118 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4120 /* Delete the handler by turning off the flag that would
4121 prevent jump_optimize from deleting it.
4122 Also permit deletion of the nonlocal labels themselves
4123 if nothing local refers to them. */
4124 if (GET_CODE (insn) == CODE_LABEL)
4128 LABEL_PRESERVE_P (insn) = 0;
4130 /* Remove it from the nonlocal_label list, to avoid confusing
4132 for (t = nonlocal_labels, last_t = 0; t;
4133 last_t = t, t = TREE_CHAIN (t))
4134 if (DECL_RTL (TREE_VALUE (t)) == insn)
4139 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4141 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4144 if (GET_CODE (insn) == INSN)
4148 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4149 if (reg_mentioned_p (t, PATTERN (insn)))
4155 || (nonlocal_goto_stack_level != 0
4156 && reg_mentioned_p (nonlocal_goto_stack_level,
4158 delete_related_insns (insn);
4163 /* Return the first insn following those generated by `assign_parms'. */
4166 get_first_nonparm_insn (void)
4169 return NEXT_INSN (last_parm_insn);
4170 return get_insns ();
4173 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4174 This means a type for which function calls must pass an address to the
4175 function or get an address back from the function.
4176 EXP may be a type node or an expression (whose type is tested). */
4179 aggregate_value_p (tree exp)
4181 int i, regno, nregs;
4184 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4186 if (TREE_CODE (type) == VOID_TYPE)
4188 if (RETURN_IN_MEMORY (type))
4190 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4191 and thus can't be returned in registers. */
4192 if (TREE_ADDRESSABLE (type))
4194 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4196 /* Make sure we have suitable call-clobbered regs to return
4197 the value in; if not, we must return it in memory. */
4198 reg = hard_function_value (type, 0, 0);
4200 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4202 if (GET_CODE (reg) != REG)
4205 regno = REGNO (reg);
4206 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4207 for (i = 0; i < nregs; i++)
4208 if (! call_used_regs[regno + i])
4213 /* Assign RTL expressions to the function's parameters.
4214 This may involve copying them into registers and using
4215 those registers as the RTL for them. */
4218 assign_parms (tree fndecl)
4221 CUMULATIVE_ARGS args_so_far;
4222 /* Total space needed so far for args on the stack,
4223 given as a constant and a tree-expression. */
4224 struct args_size stack_args_size;
4225 tree fntype = TREE_TYPE (fndecl);
4226 tree fnargs = DECL_ARGUMENTS (fndecl), orig_fnargs;
4227 /* This is used for the arg pointer when referring to stack args. */
4228 rtx internal_arg_pointer;
4229 /* This is a dummy PARM_DECL that we used for the function result if
4230 the function returns a structure. */
4231 tree function_result_decl = 0;
4232 #ifdef SETUP_INCOMING_VARARGS
4233 int varargs_setup = 0;
4235 int reg_parm_stack_space = 0;
4236 rtx conversion_insns = 0;
4238 /* Nonzero if function takes extra anonymous args.
4239 This means the last named arg must be on the stack
4240 right before the anonymous ones. */
4242 = (TYPE_ARG_TYPES (fntype) != 0
4243 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4244 != void_type_node));
4246 current_function_stdarg = stdarg;
4248 /* If the reg that the virtual arg pointer will be translated into is
4249 not a fixed reg or is the stack pointer, make a copy of the virtual
4250 arg pointer, and address parms via the copy. The frame pointer is
4251 considered fixed even though it is not marked as such.
4253 The second time through, simply use ap to avoid generating rtx. */
4255 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4256 || ! (fixed_regs[ARG_POINTER_REGNUM]
4257 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4258 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4260 internal_arg_pointer = virtual_incoming_args_rtx;
4261 current_function_internal_arg_pointer = internal_arg_pointer;
4263 stack_args_size.constant = 0;
4264 stack_args_size.var = 0;
4266 /* If struct value address is treated as the first argument, make it so. */
4267 if (aggregate_value_p (DECL_RESULT (fndecl))
4268 && ! current_function_returns_pcc_struct
4269 && struct_value_incoming_rtx == 0)
4271 tree type = build_pointer_type (TREE_TYPE (fntype));
4273 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4275 DECL_ARG_TYPE (function_result_decl) = type;
4276 TREE_CHAIN (function_result_decl) = fnargs;
4277 fnargs = function_result_decl;
4280 orig_fnargs = fnargs;
4282 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4283 parm_reg_stack_loc = ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4285 if (SPLIT_COMPLEX_ARGS)
4286 fnargs = split_complex_args (fnargs);
4288 #ifdef REG_PARM_STACK_SPACE
4289 #ifdef MAYBE_REG_PARM_STACK_SPACE
4290 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4292 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4296 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4297 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4299 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl);
4302 /* We haven't yet found an argument that we must push and pretend the
4304 current_function_pretend_args_size = 0;
4306 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4310 enum machine_mode promoted_mode, passed_mode;
4311 enum machine_mode nominal_mode, promoted_nominal_mode;
4313 struct locate_and_pad_arg_data locate;
4314 int passed_pointer = 0;
4315 int did_conversion = 0;
4316 tree passed_type = DECL_ARG_TYPE (parm);
4317 tree nominal_type = TREE_TYPE (parm);
4318 int last_named = 0, named_arg;
4322 /* Set LAST_NAMED if this is last named arg before last
4328 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4329 if (DECL_NAME (tem))
4335 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4336 most machines, if this is a varargs/stdarg function, then we treat
4337 the last named arg as if it were anonymous too. */
4338 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4340 if (TREE_TYPE (parm) == error_mark_node
4341 /* This can happen after weird syntax errors
4342 or if an enum type is defined among the parms. */
4343 || TREE_CODE (parm) != PARM_DECL
4344 || passed_type == NULL)
4346 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4347 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4348 TREE_USED (parm) = 1;
4352 /* Find mode of arg as it is passed, and mode of arg
4353 as it should be during execution of this function. */
4354 passed_mode = TYPE_MODE (passed_type);
4355 nominal_mode = TYPE_MODE (nominal_type);
4357 /* If the parm's mode is VOID, its value doesn't matter,
4358 and avoid the usual things like emit_move_insn that could crash. */
4359 if (nominal_mode == VOIDmode)
4361 SET_DECL_RTL (parm, const0_rtx);
4362 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4366 /* If the parm is to be passed as a transparent union, use the
4367 type of the first field for the tests below. We have already
4368 verified that the modes are the same. */
4369 if (DECL_TRANSPARENT_UNION (parm)
4370 || (TREE_CODE (passed_type) == UNION_TYPE
4371 && TYPE_TRANSPARENT_UNION (passed_type)))
4372 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4374 /* See if this arg was passed by invisible reference. It is if
4375 it is an object whose size depends on the contents of the
4376 object itself or if the machine requires these objects be passed
4379 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type))
4380 || TREE_ADDRESSABLE (passed_type)
4381 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4382 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4383 passed_type, named_arg)
4387 passed_type = nominal_type = build_pointer_type (passed_type);
4389 passed_mode = nominal_mode = Pmode;
4391 /* See if the frontend wants to pass this by invisible reference. */
4392 else if (passed_type != nominal_type
4393 && POINTER_TYPE_P (passed_type)
4394 && TREE_TYPE (passed_type) == nominal_type)
4396 nominal_type = passed_type;
4398 passed_mode = nominal_mode = Pmode;
4401 promoted_mode = passed_mode;
4403 #ifdef PROMOTE_FUNCTION_ARGS
4404 /* Compute the mode in which the arg is actually extended to. */
4405 unsignedp = TREE_UNSIGNED (passed_type);
4406 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4409 /* Let machine desc say which reg (if any) the parm arrives in.
4410 0 means it arrives on the stack. */
4411 #ifdef FUNCTION_INCOMING_ARG
4412 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4413 passed_type, named_arg);
4415 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4416 passed_type, named_arg);
4419 if (entry_parm == 0)
4420 promoted_mode = passed_mode;
4422 #ifdef SETUP_INCOMING_VARARGS
4423 /* If this is the last named parameter, do any required setup for
4424 varargs or stdargs. We need to know about the case of this being an
4425 addressable type, in which case we skip the registers it
4426 would have arrived in.
4428 For stdargs, LAST_NAMED will be set for two parameters, the one that
4429 is actually the last named, and the dummy parameter. We only
4430 want to do this action once.
4432 Also, indicate when RTL generation is to be suppressed. */
4433 if (last_named && !varargs_setup)
4435 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4436 current_function_pretend_args_size, 0);
4441 /* Determine parm's home in the stack,
4442 in case it arrives in the stack or we should pretend it did.
4444 Compute the stack position and rtx where the argument arrives
4447 There is one complexity here: If this was a parameter that would
4448 have been passed in registers, but wasn't only because it is
4449 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4450 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4451 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4452 0 as it was the previous time. */
4453 in_regs = entry_parm != 0;
4454 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4457 if (!in_regs && !named_arg)
4459 int pretend_named = PRETEND_OUTGOING_VARARGS_NAMED;
4462 #ifdef FUNCTION_INCOMING_ARG
4463 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4465 pretend_named) != 0;
4467 in_regs = FUNCTION_ARG (args_so_far, promoted_mode,
4469 pretend_named) != 0;
4474 /* If this parameter was passed both in registers and in the stack,
4475 use the copy on the stack. */
4476 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4479 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4481 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4482 passed_type, named_arg);
4485 memset (&locate, 0, sizeof (locate));
4486 locate_and_pad_parm (promoted_mode, passed_type, in_regs,
4487 entry_parm ? partial : 0, fndecl,
4488 &stack_args_size, &locate);
4493 /* If we're passing this arg using a reg, make its stack home
4494 the aligned stack slot. */
4496 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset);
4498 offset_rtx = ARGS_SIZE_RTX (locate.offset);
4500 if (offset_rtx == const0_rtx)
4501 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4503 stack_parm = gen_rtx_MEM (promoted_mode,
4504 gen_rtx_PLUS (Pmode,
4505 internal_arg_pointer,
4508 set_mem_attributes (stack_parm, parm, 1);
4509 if (entry_parm && MEM_ATTRS (stack_parm)->align < PARM_BOUNDARY)
4510 set_mem_align (stack_parm, PARM_BOUNDARY);
4512 /* Set also REG_ATTRS if parameter was passed in a register. */
4514 set_reg_attrs_for_parm (entry_parm, stack_parm);
4517 /* If this parm was passed part in regs and part in memory,
4518 pretend it arrived entirely in memory
4519 by pushing the register-part onto the stack.
4521 In the special case of a DImode or DFmode that is split,
4522 we could put it together in a pseudoreg directly,
4523 but for now that's not worth bothering with. */
4527 #ifndef MAYBE_REG_PARM_STACK_SPACE
4528 /* When REG_PARM_STACK_SPACE is nonzero, stack space for
4529 split parameters was allocated by our caller, so we
4530 won't be pushing it in the prolog. */
4531 if (reg_parm_stack_space == 0)
4533 current_function_pretend_args_size
4534 = (((partial * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4535 / (PARM_BOUNDARY / BITS_PER_UNIT)
4536 * (PARM_BOUNDARY / BITS_PER_UNIT));
4538 /* Handle calls that pass values in multiple non-contiguous
4539 locations. The Irix 6 ABI has examples of this. */
4540 if (GET_CODE (entry_parm) == PARALLEL)
4541 emit_group_store (validize_mem (stack_parm), entry_parm,
4543 int_size_in_bytes (TREE_TYPE (parm)));
4546 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
4549 entry_parm = stack_parm;
4552 /* If we didn't decide this parm came in a register,
4553 by default it came on the stack. */
4554 if (entry_parm == 0)
4555 entry_parm = stack_parm;
4557 /* Record permanently how this parm was passed. */
4558 DECL_INCOMING_RTL (parm) = entry_parm;
4560 /* If there is actually space on the stack for this parm,
4561 count it in stack_args_size; otherwise set stack_parm to 0
4562 to indicate there is no preallocated stack slot for the parm. */
4564 if (entry_parm == stack_parm
4565 || (GET_CODE (entry_parm) == PARALLEL
4566 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4567 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4568 /* On some machines, even if a parm value arrives in a register
4569 there is still an (uninitialized) stack slot allocated for it.
4571 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4572 whether this parameter already has a stack slot allocated,
4573 because an arg block exists only if current_function_args_size
4574 is larger than some threshold, and we haven't calculated that
4575 yet. So, for now, we just assume that stack slots never exist
4577 || REG_PARM_STACK_SPACE (fndecl) > 0
4581 stack_args_size.constant += locate.size.constant;
4582 /* locate.size doesn't include the part in regs. */
4584 stack_args_size.constant += current_function_pretend_args_size;
4585 if (locate.size.var)
4586 ADD_PARM_SIZE (stack_args_size, locate.size.var);
4589 /* No stack slot was pushed for this parm. */
4592 /* Update info on where next arg arrives in registers. */
4594 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4595 passed_type, named_arg);
4597 /* If we can't trust the parm stack slot to be aligned enough
4598 for its ultimate type, don't use that slot after entry.
4599 We'll make another stack slot, if we need one. */
4601 unsigned int thisparm_boundary
4602 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4604 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4608 /* If parm was passed in memory, and we need to convert it on entry,
4609 don't store it back in that same slot. */
4610 if (entry_parm == stack_parm
4611 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4614 /* When an argument is passed in multiple locations, we can't
4615 make use of this information, but we can save some copying if
4616 the whole argument is passed in a single register. */
4617 if (GET_CODE (entry_parm) == PARALLEL
4618 && nominal_mode != BLKmode && passed_mode != BLKmode)
4620 int i, len = XVECLEN (entry_parm, 0);
4622 for (i = 0; i < len; i++)
4623 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4624 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4625 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4627 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4629 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4630 DECL_INCOMING_RTL (parm) = entry_parm;
4635 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4636 in the mode in which it arrives.
4637 STACK_PARM is an RTX for a stack slot where the parameter can live
4638 during the function (in case we want to put it there).
4639 STACK_PARM is 0 if no stack slot was pushed for it.
4641 Now output code if necessary to convert ENTRY_PARM to
4642 the type in which this function declares it,
4643 and store that result in an appropriate place,
4644 which may be a pseudo reg, may be STACK_PARM,
4645 or may be a local stack slot if STACK_PARM is 0.
4647 Set DECL_RTL to that place. */
4649 if (nominal_mode == BLKmode
4650 #ifdef BLOCK_REG_PADDING
4651 || (locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward)
4652 && GET_MODE_SIZE (promoted_mode) < UNITS_PER_WORD)
4654 || GET_CODE (entry_parm) == PARALLEL)
4656 /* If a BLKmode arrives in registers, copy it to a stack slot.
4657 Handle calls that pass values in multiple non-contiguous
4658 locations. The Irix 6 ABI has examples of this. */
4659 if (GET_CODE (entry_parm) == REG
4660 || GET_CODE (entry_parm) == PARALLEL)
4662 int size = int_size_in_bytes (TREE_TYPE (parm));
4663 int size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
4666 /* Note that we will be storing an integral number of words.
4667 So we have to be careful to ensure that we allocate an
4668 integral number of words. We do this below in the
4669 assign_stack_local if space was not allocated in the argument
4670 list. If it was, this will not work if PARM_BOUNDARY is not
4671 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4672 if it becomes a problem. */
4674 if (stack_parm == 0)
4677 = assign_stack_local (GET_MODE (entry_parm),
4679 set_mem_attributes (stack_parm, parm, 1);
4682 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4685 mem = validize_mem (stack_parm);
4687 /* Handle calls that pass values in multiple non-contiguous
4688 locations. The Irix 6 ABI has examples of this. */
4689 if (GET_CODE (entry_parm) == PARALLEL)
4690 emit_group_store (mem, entry_parm, TREE_TYPE (parm), size);
4695 /* If SIZE is that of a mode no bigger than a word, just use
4696 that mode's store operation. */
4697 else if (size <= UNITS_PER_WORD)
4699 enum machine_mode mode
4700 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
4703 #ifdef BLOCK_REG_PADDING
4704 && (size == UNITS_PER_WORD
4705 || (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4706 != (BYTES_BIG_ENDIAN ? upward : downward)))
4710 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
4711 emit_move_insn (change_address (mem, mode, 0), reg);
4714 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
4715 machine must be aligned to the left before storing
4716 to memory. Note that the previous test doesn't
4717 handle all cases (e.g. SIZE == 3). */
4718 else if (size != UNITS_PER_WORD
4719 #ifdef BLOCK_REG_PADDING
4720 && (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4728 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4729 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
4731 x = expand_binop (word_mode, ashl_optab, reg,
4732 GEN_INT (by), 0, 1, OPTAB_WIDEN);
4733 tem = change_address (mem, word_mode, 0);
4734 emit_move_insn (tem, x);
4737 move_block_from_reg (REGNO (entry_parm), mem,
4738 size_stored / UNITS_PER_WORD);
4741 move_block_from_reg (REGNO (entry_parm), mem,
4742 size_stored / UNITS_PER_WORD);
4744 SET_DECL_RTL (parm, stack_parm);
4746 else if (! ((! optimize
4747 && ! DECL_REGISTER (parm))
4748 || TREE_SIDE_EFFECTS (parm)
4749 /* If -ffloat-store specified, don't put explicit
4750 float variables into registers. */
4751 || (flag_float_store
4752 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4753 /* Always assign pseudo to structure return or item passed
4754 by invisible reference. */
4755 || passed_pointer || parm == function_result_decl)
4757 /* Store the parm in a pseudoregister during the function, but we
4758 may need to do it in a wider mode. */
4761 unsigned int regno, regnoi = 0, regnor = 0;
4763 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4765 promoted_nominal_mode
4766 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4768 parmreg = gen_reg_rtx (promoted_nominal_mode);
4769 mark_user_reg (parmreg);
4771 /* If this was an item that we received a pointer to, set DECL_RTL
4775 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4777 set_mem_attributes (x, parm, 1);
4778 SET_DECL_RTL (parm, x);
4782 SET_DECL_RTL (parm, parmreg);
4783 maybe_set_unchanging (DECL_RTL (parm), parm);
4786 /* Copy the value into the register. */
4787 if (nominal_mode != passed_mode
4788 || promoted_nominal_mode != promoted_mode)
4791 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4792 mode, by the caller. We now have to convert it to
4793 NOMINAL_MODE, if different. However, PARMREG may be in
4794 a different mode than NOMINAL_MODE if it is being stored
4797 If ENTRY_PARM is a hard register, it might be in a register
4798 not valid for operating in its mode (e.g., an odd-numbered
4799 register for a DFmode). In that case, moves are the only
4800 thing valid, so we can't do a convert from there. This
4801 occurs when the calling sequence allow such misaligned
4804 In addition, the conversion may involve a call, which could
4805 clobber parameters which haven't been copied to pseudo
4806 registers yet. Therefore, we must first copy the parm to
4807 a pseudo reg here, and save the conversion until after all
4808 parameters have been moved. */
4810 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4812 emit_move_insn (tempreg, validize_mem (entry_parm));
4814 push_to_sequence (conversion_insns);
4815 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4817 if (GET_CODE (tempreg) == SUBREG
4818 && GET_MODE (tempreg) == nominal_mode
4819 && GET_CODE (SUBREG_REG (tempreg)) == REG
4820 && nominal_mode == passed_mode
4821 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4822 && GET_MODE_SIZE (GET_MODE (tempreg))
4823 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4825 /* The argument is already sign/zero extended, so note it
4827 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4828 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4831 /* TREE_USED gets set erroneously during expand_assignment. */
4832 save_tree_used = TREE_USED (parm);
4833 expand_assignment (parm,
4834 make_tree (nominal_type, tempreg), 0);
4835 TREE_USED (parm) = save_tree_used;
4836 conversion_insns = get_insns ();
4841 emit_move_insn (parmreg, validize_mem (entry_parm));
4843 /* If we were passed a pointer but the actual value
4844 can safely live in a register, put it in one. */
4845 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4846 /* If by-reference argument was promoted, demote it. */
4847 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4849 && ! DECL_REGISTER (parm))
4850 || TREE_SIDE_EFFECTS (parm)
4851 /* If -ffloat-store specified, don't put explicit
4852 float variables into registers. */
4853 || (flag_float_store
4854 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4856 /* We can't use nominal_mode, because it will have been set to
4857 Pmode above. We must use the actual mode of the parm. */
4858 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4859 mark_user_reg (parmreg);
4860 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4862 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4863 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4864 push_to_sequence (conversion_insns);
4865 emit_move_insn (tempreg, DECL_RTL (parm));
4867 convert_to_mode (GET_MODE (parmreg),
4870 emit_move_insn (parmreg, DECL_RTL (parm));
4871 conversion_insns = get_insns();
4876 emit_move_insn (parmreg, DECL_RTL (parm));
4877 SET_DECL_RTL (parm, parmreg);
4878 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4882 #ifdef FUNCTION_ARG_CALLEE_COPIES
4883 /* If we are passed an arg by reference and it is our responsibility
4884 to make a copy, do it now.
4885 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4886 original argument, so we must recreate them in the call to
4887 FUNCTION_ARG_CALLEE_COPIES. */
4888 /* ??? Later add code to handle the case that if the argument isn't
4889 modified, don't do the copy. */
4891 else if (passed_pointer
4892 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4893 TYPE_MODE (DECL_ARG_TYPE (parm)),
4894 DECL_ARG_TYPE (parm),
4896 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4899 tree type = DECL_ARG_TYPE (parm);
4901 /* This sequence may involve a library call perhaps clobbering
4902 registers that haven't been copied to pseudos yet. */
4904 push_to_sequence (conversion_insns);
4906 if (!COMPLETE_TYPE_P (type)
4907 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4908 /* This is a variable sized object. */
4909 copy = gen_rtx_MEM (BLKmode,
4910 allocate_dynamic_stack_space
4911 (expr_size (parm), NULL_RTX,
4912 TYPE_ALIGN (type)));
4914 copy = assign_stack_temp (TYPE_MODE (type),
4915 int_size_in_bytes (type), 1);
4916 set_mem_attributes (copy, parm, 1);
4918 store_expr (parm, copy, 0);
4919 emit_move_insn (parmreg, XEXP (copy, 0));
4920 conversion_insns = get_insns ();
4924 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4926 /* In any case, record the parm's desired stack location
4927 in case we later discover it must live in the stack.
4929 If it is a COMPLEX value, store the stack location for both
4932 if (GET_CODE (parmreg) == CONCAT)
4933 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4935 regno = REGNO (parmreg);
4937 if (regno >= max_parm_reg)
4940 int old_max_parm_reg = max_parm_reg;
4942 /* It's slow to expand this one register at a time,
4943 but it's also rare and we need max_parm_reg to be
4944 precisely correct. */
4945 max_parm_reg = regno + 1;
4946 new = ggc_realloc (parm_reg_stack_loc,
4947 max_parm_reg * sizeof (rtx));
4948 memset (new + old_max_parm_reg, 0,
4949 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4950 parm_reg_stack_loc = new;
4953 if (GET_CODE (parmreg) == CONCAT)
4955 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4957 regnor = REGNO (gen_realpart (submode, parmreg));
4958 regnoi = REGNO (gen_imagpart (submode, parmreg));
4960 if (stack_parm != 0)
4962 parm_reg_stack_loc[regnor]
4963 = gen_realpart (submode, stack_parm);
4964 parm_reg_stack_loc[regnoi]
4965 = gen_imagpart (submode, stack_parm);
4969 parm_reg_stack_loc[regnor] = 0;
4970 parm_reg_stack_loc[regnoi] = 0;
4974 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4976 /* Mark the register as eliminable if we did no conversion
4977 and it was copied from memory at a fixed offset,
4978 and the arg pointer was not copied to a pseudo-reg.
4979 If the arg pointer is a pseudo reg or the offset formed
4980 an invalid address, such memory-equivalences
4981 as we make here would screw up life analysis for it. */
4982 if (nominal_mode == passed_mode
4985 && GET_CODE (stack_parm) == MEM
4986 && locate.offset.var == 0
4987 && reg_mentioned_p (virtual_incoming_args_rtx,
4988 XEXP (stack_parm, 0)))
4990 rtx linsn = get_last_insn ();
4993 /* Mark complex types separately. */
4994 if (GET_CODE (parmreg) == CONCAT)
4995 /* Scan backwards for the set of the real and
4997 for (sinsn = linsn; sinsn != 0;
4998 sinsn = prev_nonnote_insn (sinsn))
5000 set = single_set (sinsn);
5002 && SET_DEST (set) == regno_reg_rtx [regnoi])
5004 = gen_rtx_EXPR_LIST (REG_EQUIV,
5005 parm_reg_stack_loc[regnoi],
5008 && SET_DEST (set) == regno_reg_rtx [regnor])
5010 = gen_rtx_EXPR_LIST (REG_EQUIV,
5011 parm_reg_stack_loc[regnor],
5014 else if ((set = single_set (linsn)) != 0
5015 && SET_DEST (set) == parmreg)
5017 = gen_rtx_EXPR_LIST (REG_EQUIV,
5018 stack_parm, REG_NOTES (linsn));
5021 /* For pointer data type, suggest pointer register. */
5022 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5023 mark_reg_pointer (parmreg,
5024 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5026 /* If something wants our address, try to use ADDRESSOF. */
5027 if (TREE_ADDRESSABLE (parm))
5029 /* If we end up putting something into the stack,
5030 fixup_var_refs_insns will need to make a pass over
5031 all the instructions. It looks through the pending
5032 sequences -- but it can't see the ones in the
5033 CONVERSION_INSNS, if they're not on the sequence
5034 stack. So, we go back to that sequence, just so that
5035 the fixups will happen. */
5036 push_to_sequence (conversion_insns);
5037 put_var_into_stack (parm, /*rescan=*/true);
5038 conversion_insns = get_insns ();
5044 /* Value must be stored in the stack slot STACK_PARM
5045 during function execution. */
5047 if (promoted_mode != nominal_mode)
5049 /* Conversion is required. */
5050 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5052 emit_move_insn (tempreg, validize_mem (entry_parm));
5054 push_to_sequence (conversion_insns);
5055 entry_parm = convert_to_mode (nominal_mode, tempreg,
5056 TREE_UNSIGNED (TREE_TYPE (parm)));
5058 /* ??? This may need a big-endian conversion on sparc64. */
5059 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5061 conversion_insns = get_insns ();
5066 if (entry_parm != stack_parm)
5068 if (stack_parm == 0)
5071 = assign_stack_local (GET_MODE (entry_parm),
5072 GET_MODE_SIZE (GET_MODE (entry_parm)),
5074 set_mem_attributes (stack_parm, parm, 1);
5077 if (promoted_mode != nominal_mode)
5079 push_to_sequence (conversion_insns);
5080 emit_move_insn (validize_mem (stack_parm),
5081 validize_mem (entry_parm));
5082 conversion_insns = get_insns ();
5086 emit_move_insn (validize_mem (stack_parm),
5087 validize_mem (entry_parm));
5090 SET_DECL_RTL (parm, stack_parm);
5094 if (SPLIT_COMPLEX_ARGS && fnargs != orig_fnargs)
5096 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
5098 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE)
5101 gen_rtx_CONCAT (DECL_MODE (parm),
5103 DECL_RTL (TREE_CHAIN (fnargs))));
5104 DECL_INCOMING_RTL (parm)
5105 = gen_rtx_CONCAT (DECL_MODE (parm),
5106 DECL_INCOMING_RTL (fnargs),
5107 DECL_INCOMING_RTL (TREE_CHAIN (fnargs)));
5108 fnargs = TREE_CHAIN (fnargs);
5112 SET_DECL_RTL (parm, DECL_RTL (fnargs));
5113 DECL_INCOMING_RTL (parm) = DECL_INCOMING_RTL (fnargs);
5115 fnargs = TREE_CHAIN (fnargs);
5119 /* Output all parameter conversion instructions (possibly including calls)
5120 now that all parameters have been copied out of hard registers. */
5121 emit_insn (conversion_insns);
5123 /* If we are receiving a struct value address as the first argument, set up
5124 the RTL for the function result. As this might require code to convert
5125 the transmitted address to Pmode, we do this here to ensure that possible
5126 preliminary conversions of the address have been emitted already. */
5127 if (function_result_decl)
5129 tree result = DECL_RESULT (fndecl);
5130 rtx addr = DECL_RTL (function_result_decl);
5133 #ifdef POINTERS_EXTEND_UNSIGNED
5134 if (GET_MODE (addr) != Pmode)
5135 addr = convert_memory_address (Pmode, addr);
5138 x = gen_rtx_MEM (DECL_MODE (result), addr);
5139 set_mem_attributes (x, result, 1);
5140 SET_DECL_RTL (result, x);
5143 last_parm_insn = get_last_insn ();
5145 current_function_args_size = stack_args_size.constant;
5147 /* Adjust function incoming argument size for alignment and
5150 #ifdef REG_PARM_STACK_SPACE
5151 #ifndef MAYBE_REG_PARM_STACK_SPACE
5152 current_function_args_size = MAX (current_function_args_size,
5153 REG_PARM_STACK_SPACE (fndecl));
5157 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5159 current_function_args_size
5160 = ((current_function_args_size + STACK_BYTES - 1)
5161 / STACK_BYTES) * STACK_BYTES;
5163 #ifdef ARGS_GROW_DOWNWARD
5164 current_function_arg_offset_rtx
5165 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5166 : expand_expr (size_diffop (stack_args_size.var,
5167 size_int (-stack_args_size.constant)),
5168 NULL_RTX, VOIDmode, 0));
5170 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5173 /* See how many bytes, if any, of its args a function should try to pop
5176 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5177 current_function_args_size);
5179 /* For stdarg.h function, save info about
5180 regs and stack space used by the named args. */
5182 current_function_args_info = args_so_far;
5184 /* Set the rtx used for the function return value. Put this in its
5185 own variable so any optimizers that need this information don't have
5186 to include tree.h. Do this here so it gets done when an inlined
5187 function gets output. */
5189 current_function_return_rtx
5190 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5191 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5193 /* If scalar return value was computed in a pseudo-reg, or was a named
5194 return value that got dumped to the stack, copy that to the hard
5196 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5198 tree decl_result = DECL_RESULT (fndecl);
5199 rtx decl_rtl = DECL_RTL (decl_result);
5201 if (REG_P (decl_rtl)
5202 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5203 : DECL_REGISTER (decl_result))
5207 #ifdef FUNCTION_OUTGOING_VALUE
5208 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5211 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5214 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5215 /* The delay slot scheduler assumes that current_function_return_rtx
5216 holds the hard register containing the return value, not a
5217 temporary pseudo. */
5218 current_function_return_rtx = real_decl_rtl;
5223 /* If ARGS contains entries with complex types, split the entry into two
5224 entries of the component type. Return a new list of substitutions are
5225 needed, else the old list. */
5228 split_complex_args (tree args)
5232 /* Before allocating memory, check for the common case of no complex. */
5233 for (p = args; p; p = TREE_CHAIN (p))
5234 if (TREE_CODE (TREE_TYPE (p)) == COMPLEX_TYPE)
5239 args = copy_list (args);
5241 for (p = args; p; p = TREE_CHAIN (p))
5243 tree type = TREE_TYPE (p);
5244 if (TREE_CODE (type) == COMPLEX_TYPE)
5247 tree subtype = TREE_TYPE (type);
5249 /* Rewrite the PARM_DECL's type with its component. */
5250 TREE_TYPE (p) = subtype;
5251 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
5252 DECL_MODE (p) = VOIDmode;
5253 DECL_SIZE (p) = NULL;
5254 DECL_SIZE_UNIT (p) = NULL;
5257 /* Build a second synthetic decl. */
5258 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
5259 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
5260 layout_decl (decl, 0);
5262 /* Splice it in; skip the new decl. */
5263 TREE_CHAIN (decl) = TREE_CHAIN (p);
5264 TREE_CHAIN (p) = decl;
5272 /* Indicate whether REGNO is an incoming argument to the current function
5273 that was promoted to a wider mode. If so, return the RTX for the
5274 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5275 that REGNO is promoted from and whether the promotion was signed or
5278 #ifdef PROMOTE_FUNCTION_ARGS
5281 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
5285 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5286 arg = TREE_CHAIN (arg))
5287 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5288 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5289 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5291 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5292 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5294 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5295 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5296 && mode != DECL_MODE (arg))
5298 *pmode = DECL_MODE (arg);
5299 *punsignedp = unsignedp;
5300 return DECL_INCOMING_RTL (arg);
5309 /* Compute the size and offset from the start of the stacked arguments for a
5310 parm passed in mode PASSED_MODE and with type TYPE.
5312 INITIAL_OFFSET_PTR points to the current offset into the stacked
5315 The starting offset and size for this parm are returned in
5316 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5317 nonzero, the offset is that of stack slot, which is returned in
5318 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5319 padding required from the initial offset ptr to the stack slot.
5321 IN_REGS is nonzero if the argument will be passed in registers. It will
5322 never be set if REG_PARM_STACK_SPACE is not defined.
5324 FNDECL is the function in which the argument was defined.
5326 There are two types of rounding that are done. The first, controlled by
5327 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5328 list to be aligned to the specific boundary (in bits). This rounding
5329 affects the initial and starting offsets, but not the argument size.
5331 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5332 optionally rounds the size of the parm to PARM_BOUNDARY. The
5333 initial offset is not affected by this rounding, while the size always
5334 is and the starting offset may be. */
5336 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5337 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5338 callers pass in the total size of args so far as
5339 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5342 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
5343 int partial, tree fndecl ATTRIBUTE_UNUSED,
5344 struct args_size *initial_offset_ptr,
5345 struct locate_and_pad_arg_data *locate)
5348 enum direction where_pad;
5350 int reg_parm_stack_space = 0;
5351 int part_size_in_regs;
5353 #ifdef REG_PARM_STACK_SPACE
5354 #ifdef MAYBE_REG_PARM_STACK_SPACE
5355 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5357 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5360 /* If we have found a stack parm before we reach the end of the
5361 area reserved for registers, skip that area. */
5364 if (reg_parm_stack_space > 0)
5366 if (initial_offset_ptr->var)
5368 initial_offset_ptr->var
5369 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5370 ssize_int (reg_parm_stack_space));
5371 initial_offset_ptr->constant = 0;
5373 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5374 initial_offset_ptr->constant = reg_parm_stack_space;
5377 #endif /* REG_PARM_STACK_SPACE */
5379 part_size_in_regs = 0;
5380 if (reg_parm_stack_space == 0)
5381 part_size_in_regs = ((partial * UNITS_PER_WORD)
5382 / (PARM_BOUNDARY / BITS_PER_UNIT)
5383 * (PARM_BOUNDARY / BITS_PER_UNIT));
5386 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5387 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5388 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5389 locate->where_pad = where_pad;
5391 #ifdef ARGS_GROW_DOWNWARD
5392 locate->slot_offset.constant = -initial_offset_ptr->constant;
5393 if (initial_offset_ptr->var)
5394 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
5395 initial_offset_ptr->var);
5399 if (where_pad != none
5400 && (!host_integerp (sizetree, 1)
5401 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5402 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5403 SUB_PARM_SIZE (locate->slot_offset, s2);
5406 locate->slot_offset.constant += part_size_in_regs;
5409 #ifdef REG_PARM_STACK_SPACE
5410 || REG_PARM_STACK_SPACE (fndecl) > 0
5413 pad_to_arg_alignment (&locate->slot_offset, boundary,
5414 &locate->alignment_pad);
5416 locate->size.constant = (-initial_offset_ptr->constant
5417 - locate->slot_offset.constant);
5418 if (initial_offset_ptr->var)
5419 locate->size.var = size_binop (MINUS_EXPR,
5420 size_binop (MINUS_EXPR,
5422 initial_offset_ptr->var),
5423 locate->slot_offset.var);
5425 /* Pad_below needs the pre-rounded size to know how much to pad
5427 locate->offset = locate->slot_offset;
5428 if (where_pad == downward)
5429 pad_below (&locate->offset, passed_mode, sizetree);
5431 #else /* !ARGS_GROW_DOWNWARD */
5433 #ifdef REG_PARM_STACK_SPACE
5434 || REG_PARM_STACK_SPACE (fndecl) > 0
5437 pad_to_arg_alignment (initial_offset_ptr, boundary,
5438 &locate->alignment_pad);
5439 locate->slot_offset = *initial_offset_ptr;
5441 #ifdef PUSH_ROUNDING
5442 if (passed_mode != BLKmode)
5443 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5446 /* Pad_below needs the pre-rounded size to know how much to pad below
5447 so this must be done before rounding up. */
5448 locate->offset = locate->slot_offset;
5449 if (where_pad == downward)
5450 pad_below (&locate->offset, passed_mode, sizetree);
5452 if (where_pad != none
5453 && (!host_integerp (sizetree, 1)
5454 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5455 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5457 ADD_PARM_SIZE (locate->size, sizetree);
5459 locate->size.constant -= part_size_in_regs;
5460 #endif /* ARGS_GROW_DOWNWARD */
5463 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5464 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5467 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
5468 struct args_size *alignment_pad)
5470 tree save_var = NULL_TREE;
5471 HOST_WIDE_INT save_constant = 0;
5473 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5475 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5477 save_var = offset_ptr->var;
5478 save_constant = offset_ptr->constant;
5481 alignment_pad->var = NULL_TREE;
5482 alignment_pad->constant = 0;
5484 if (boundary > BITS_PER_UNIT)
5486 if (offset_ptr->var)
5489 #ifdef ARGS_GROW_DOWNWARD
5494 (ARGS_SIZE_TREE (*offset_ptr),
5495 boundary / BITS_PER_UNIT);
5496 /* ARGS_SIZE_TREE includes constant term. */
5497 offset_ptr->constant = 0;
5498 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5499 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5504 offset_ptr->constant =
5505 #ifdef ARGS_GROW_DOWNWARD
5506 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5508 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5510 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5511 alignment_pad->constant = offset_ptr->constant - save_constant;
5517 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
5519 if (passed_mode != BLKmode)
5521 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5522 offset_ptr->constant
5523 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5524 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5525 - GET_MODE_SIZE (passed_mode));
5529 if (TREE_CODE (sizetree) != INTEGER_CST
5530 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5532 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5533 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5535 ADD_PARM_SIZE (*offset_ptr, s2);
5536 SUB_PARM_SIZE (*offset_ptr, sizetree);
5541 /* Walk the tree of blocks describing the binding levels within a function
5542 and warn about uninitialized variables.
5543 This is done after calling flow_analysis and before global_alloc
5544 clobbers the pseudo-regs to hard regs. */
5547 uninitialized_vars_warning (tree block)
5550 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5552 if (warn_uninitialized
5553 && TREE_CODE (decl) == VAR_DECL
5554 /* These warnings are unreliable for and aggregates
5555 because assigning the fields one by one can fail to convince
5556 flow.c that the entire aggregate was initialized.
5557 Unions are troublesome because members may be shorter. */
5558 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5559 && DECL_RTL (decl) != 0
5560 && GET_CODE (DECL_RTL (decl)) == REG
5561 /* Global optimizations can make it difficult to determine if a
5562 particular variable has been initialized. However, a VAR_DECL
5563 with a nonzero DECL_INITIAL had an initializer, so do not
5564 claim it is potentially uninitialized.
5566 We do not care about the actual value in DECL_INITIAL, so we do
5567 not worry that it may be a dangling pointer. */
5568 && DECL_INITIAL (decl) == NULL_TREE
5569 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5570 warning_with_decl (decl,
5571 "`%s' might be used uninitialized in this function");
5573 && TREE_CODE (decl) == VAR_DECL
5574 && DECL_RTL (decl) != 0
5575 && GET_CODE (DECL_RTL (decl)) == REG
5576 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5577 warning_with_decl (decl,
5578 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5580 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5581 uninitialized_vars_warning (sub);
5584 /* Do the appropriate part of uninitialized_vars_warning
5585 but for arguments instead of local variables. */
5588 setjmp_args_warning (void)
5591 for (decl = DECL_ARGUMENTS (current_function_decl);
5592 decl; decl = TREE_CHAIN (decl))
5593 if (DECL_RTL (decl) != 0
5594 && GET_CODE (DECL_RTL (decl)) == REG
5595 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5596 warning_with_decl (decl,
5597 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5600 /* If this function call setjmp, put all vars into the stack
5601 unless they were declared `register'. */
5604 setjmp_protect (tree block)
5607 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5608 if ((TREE_CODE (decl) == VAR_DECL
5609 || TREE_CODE (decl) == PARM_DECL)
5610 && DECL_RTL (decl) != 0
5611 && (GET_CODE (DECL_RTL (decl)) == REG
5612 || (GET_CODE (DECL_RTL (decl)) == MEM
5613 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5614 /* If this variable came from an inline function, it must be
5615 that its life doesn't overlap the setjmp. If there was a
5616 setjmp in the function, it would already be in memory. We
5617 must exclude such variable because their DECL_RTL might be
5618 set to strange things such as virtual_stack_vars_rtx. */
5619 && ! DECL_FROM_INLINE (decl)
5621 #ifdef NON_SAVING_SETJMP
5622 /* If longjmp doesn't restore the registers,
5623 don't put anything in them. */
5627 ! DECL_REGISTER (decl)))
5628 put_var_into_stack (decl, /*rescan=*/true);
5629 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5630 setjmp_protect (sub);
5633 /* Like the previous function, but for args instead of local variables. */
5636 setjmp_protect_args (void)
5639 for (decl = DECL_ARGUMENTS (current_function_decl);
5640 decl; decl = TREE_CHAIN (decl))
5641 if ((TREE_CODE (decl) == VAR_DECL
5642 || TREE_CODE (decl) == PARM_DECL)
5643 && DECL_RTL (decl) != 0
5644 && (GET_CODE (DECL_RTL (decl)) == REG
5645 || (GET_CODE (DECL_RTL (decl)) == MEM
5646 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5648 /* If longjmp doesn't restore the registers,
5649 don't put anything in them. */
5650 #ifdef NON_SAVING_SETJMP
5654 ! DECL_REGISTER (decl)))
5655 put_var_into_stack (decl, /*rescan=*/true);
5658 /* Return the context-pointer register corresponding to DECL,
5659 or 0 if it does not need one. */
5662 lookup_static_chain (tree decl)
5664 tree context = decl_function_context (decl);
5668 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5671 /* We treat inline_function_decl as an alias for the current function
5672 because that is the inline function whose vars, types, etc.
5673 are being merged into the current function.
5674 See expand_inline_function. */
5675 if (context == current_function_decl || context == inline_function_decl)
5676 return virtual_stack_vars_rtx;
5678 for (link = context_display; link; link = TREE_CHAIN (link))
5679 if (TREE_PURPOSE (link) == context)
5680 return RTL_EXPR_RTL (TREE_VALUE (link));
5685 /* Convert a stack slot address ADDR for variable VAR
5686 (from a containing function)
5687 into an address valid in this function (using a static chain). */
5690 fix_lexical_addr (rtx addr, tree var)
5693 HOST_WIDE_INT displacement;
5694 tree context = decl_function_context (var);
5695 struct function *fp;
5698 /* If this is the present function, we need not do anything. */
5699 if (context == current_function_decl || context == inline_function_decl)
5702 fp = find_function_data (context);
5704 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5705 addr = XEXP (XEXP (addr, 0), 0);
5707 /* Decode given address as base reg plus displacement. */
5708 if (GET_CODE (addr) == REG)
5709 basereg = addr, displacement = 0;
5710 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5711 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5715 /* We accept vars reached via the containing function's
5716 incoming arg pointer and via its stack variables pointer. */
5717 if (basereg == fp->internal_arg_pointer)
5719 /* If reached via arg pointer, get the arg pointer value
5720 out of that function's stack frame.
5722 There are two cases: If a separate ap is needed, allocate a
5723 slot in the outer function for it and dereference it that way.
5724 This is correct even if the real ap is actually a pseudo.
5725 Otherwise, just adjust the offset from the frame pointer to
5728 #ifdef NEED_SEPARATE_AP
5731 addr = get_arg_pointer_save_area (fp);
5732 addr = fix_lexical_addr (XEXP (addr, 0), var);
5733 addr = memory_address (Pmode, addr);
5735 base = gen_rtx_MEM (Pmode, addr);
5736 set_mem_alias_set (base, get_frame_alias_set ());
5737 base = copy_to_reg (base);
5739 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5740 base = lookup_static_chain (var);
5744 else if (basereg == virtual_stack_vars_rtx)
5746 /* This is the same code as lookup_static_chain, duplicated here to
5747 avoid an extra call to decl_function_context. */
5750 for (link = context_display; link; link = TREE_CHAIN (link))
5751 if (TREE_PURPOSE (link) == context)
5753 base = RTL_EXPR_RTL (TREE_VALUE (link));
5761 /* Use same offset, relative to appropriate static chain or argument
5763 return plus_constant (base, displacement);
5766 /* Return the address of the trampoline for entering nested fn FUNCTION.
5767 If necessary, allocate a trampoline (in the stack frame)
5768 and emit rtl to initialize its contents (at entry to this function). */
5771 trampoline_address (tree function)
5776 struct function *fp;
5779 /* Find an existing trampoline and return it. */
5780 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5781 if (TREE_PURPOSE (link) == function)
5783 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5785 for (fp = outer_function_chain; fp; fp = fp->outer)
5786 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5787 if (TREE_PURPOSE (link) == function)
5789 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5791 return adjust_trampoline_addr (tramp);
5794 /* None exists; we must make one. */
5796 /* Find the `struct function' for the function containing FUNCTION. */
5798 fn_context = decl_function_context (function);
5799 if (fn_context != current_function_decl
5800 && fn_context != inline_function_decl)
5801 fp = find_function_data (fn_context);
5803 /* Allocate run-time space for this trampoline. */
5804 /* If rounding needed, allocate extra space
5805 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5806 #define TRAMPOLINE_REAL_SIZE \
5807 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5808 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5810 /* Record the trampoline for reuse and note it for later initialization
5811 by expand_function_end. */
5814 rtlexp = make_node (RTL_EXPR);
5815 RTL_EXPR_RTL (rtlexp) = tramp;
5816 fp->x_trampoline_list = tree_cons (function, rtlexp,
5817 fp->x_trampoline_list);
5821 /* Make the RTL_EXPR node temporary, not momentary, so that the
5822 trampoline_list doesn't become garbage. */
5823 rtlexp = make_node (RTL_EXPR);
5825 RTL_EXPR_RTL (rtlexp) = tramp;
5826 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5829 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5830 return adjust_trampoline_addr (tramp);
5833 /* Given a trampoline address,
5834 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5837 round_trampoline_addr (rtx tramp)
5839 /* Round address up to desired boundary. */
5840 rtx temp = gen_reg_rtx (Pmode);
5841 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5842 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5844 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5845 temp, 0, OPTAB_LIB_WIDEN);
5846 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5847 temp, 0, OPTAB_LIB_WIDEN);
5852 /* Given a trampoline address, round it then apply any
5853 platform-specific adjustments so that the result can be used for a
5857 adjust_trampoline_addr (rtx tramp)
5859 tramp = round_trampoline_addr (tramp);
5860 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5861 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5866 /* Put all this function's BLOCK nodes including those that are chained
5867 onto the first block into a vector, and return it.
5868 Also store in each NOTE for the beginning or end of a block
5869 the index of that block in the vector.
5870 The arguments are BLOCK, the chain of top-level blocks of the function,
5871 and INSNS, the insn chain of the function. */
5874 identify_blocks (void)
5877 tree *block_vector, *last_block_vector;
5879 tree block = DECL_INITIAL (current_function_decl);
5884 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5885 depth-first order. */
5886 block_vector = get_block_vector (block, &n_blocks);
5887 block_stack = xmalloc (n_blocks * sizeof (tree));
5889 last_block_vector = identify_blocks_1 (get_insns (),
5891 block_vector + n_blocks,
5894 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5895 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5896 if (0 && last_block_vector != block_vector + n_blocks)
5899 free (block_vector);
5903 /* Subroutine of identify_blocks. Do the block substitution on the
5904 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5906 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5907 BLOCK_VECTOR is incremented for each block seen. */
5910 identify_blocks_1 (rtx insns, tree *block_vector, tree *end_block_vector,
5911 tree *orig_block_stack)
5914 tree *block_stack = orig_block_stack;
5916 for (insn = insns; insn; insn = NEXT_INSN (insn))
5918 if (GET_CODE (insn) == NOTE)
5920 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5924 /* If there are more block notes than BLOCKs, something
5926 if (block_vector == end_block_vector)
5929 b = *block_vector++;
5930 NOTE_BLOCK (insn) = b;
5933 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5935 /* If there are more NOTE_INSN_BLOCK_ENDs than
5936 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5937 if (block_stack == orig_block_stack)
5940 NOTE_BLOCK (insn) = *--block_stack;
5943 else if (GET_CODE (insn) == CALL_INSN
5944 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5946 rtx cp = PATTERN (insn);
5948 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5949 end_block_vector, block_stack);
5951 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5952 end_block_vector, block_stack);
5954 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5955 end_block_vector, block_stack);
5959 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5960 something is badly wrong. */
5961 if (block_stack != orig_block_stack)
5964 return block_vector;
5967 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5968 and create duplicate blocks. */
5969 /* ??? Need an option to either create block fragments or to create
5970 abstract origin duplicates of a source block. It really depends
5971 on what optimization has been performed. */
5974 reorder_blocks (void)
5976 tree block = DECL_INITIAL (current_function_decl);
5977 varray_type block_stack;
5979 if (block == NULL_TREE)
5982 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5984 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5985 reorder_blocks_0 (block);
5987 /* Prune the old trees away, so that they don't get in the way. */
5988 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5989 BLOCK_CHAIN (block) = NULL_TREE;
5991 /* Recreate the block tree from the note nesting. */
5992 reorder_blocks_1 (get_insns (), block, &block_stack);
5993 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5995 /* Remove deleted blocks from the block fragment chains. */
5996 reorder_fix_fragments (block);
5999 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
6002 reorder_blocks_0 (tree block)
6006 TREE_ASM_WRITTEN (block) = 0;
6007 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
6008 block = BLOCK_CHAIN (block);
6013 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack)
6017 for (insn = insns; insn; insn = NEXT_INSN (insn))
6019 if (GET_CODE (insn) == NOTE)
6021 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6023 tree block = NOTE_BLOCK (insn);
6025 /* If we have seen this block before, that means it now
6026 spans multiple address regions. Create a new fragment. */
6027 if (TREE_ASM_WRITTEN (block))
6029 tree new_block = copy_node (block);
6032 origin = (BLOCK_FRAGMENT_ORIGIN (block)
6033 ? BLOCK_FRAGMENT_ORIGIN (block)
6035 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
6036 BLOCK_FRAGMENT_CHAIN (new_block)
6037 = BLOCK_FRAGMENT_CHAIN (origin);
6038 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
6040 NOTE_BLOCK (insn) = new_block;
6044 BLOCK_SUBBLOCKS (block) = 0;
6045 TREE_ASM_WRITTEN (block) = 1;
6046 /* When there's only one block for the entire function,
6047 current_block == block and we mustn't do this, it
6048 will cause infinite recursion. */
6049 if (block != current_block)
6051 BLOCK_SUPERCONTEXT (block) = current_block;
6052 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6053 BLOCK_SUBBLOCKS (current_block) = block;
6054 current_block = block;
6056 VARRAY_PUSH_TREE (*p_block_stack, block);
6058 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6060 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6061 VARRAY_POP (*p_block_stack);
6062 BLOCK_SUBBLOCKS (current_block)
6063 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6064 current_block = BLOCK_SUPERCONTEXT (current_block);
6067 else if (GET_CODE (insn) == CALL_INSN
6068 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6070 rtx cp = PATTERN (insn);
6071 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
6073 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6075 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6080 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6081 appears in the block tree, select one of the fragments to become
6082 the new origin block. */
6085 reorder_fix_fragments (tree block)
6089 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6090 tree new_origin = NULL_TREE;
6094 if (! TREE_ASM_WRITTEN (dup_origin))
6096 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6098 /* Find the first of the remaining fragments. There must
6099 be at least one -- the current block. */
6100 while (! TREE_ASM_WRITTEN (new_origin))
6101 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6102 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6105 else if (! dup_origin)
6108 /* Re-root the rest of the fragments to the new origin. In the
6109 case that DUP_ORIGIN was null, that means BLOCK was the origin
6110 of a chain of fragments and we want to remove those fragments
6111 that didn't make it to the output. */
6114 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6119 if (TREE_ASM_WRITTEN (chain))
6121 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6123 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6125 chain = BLOCK_FRAGMENT_CHAIN (chain);
6130 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6131 block = BLOCK_CHAIN (block);
6135 /* Reverse the order of elements in the chain T of blocks,
6136 and return the new head of the chain (old last element). */
6139 blocks_nreverse (tree t)
6141 tree prev = 0, decl, next;
6142 for (decl = t; decl; decl = next)
6144 next = BLOCK_CHAIN (decl);
6145 BLOCK_CHAIN (decl) = prev;
6151 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6152 non-NULL, list them all into VECTOR, in a depth-first preorder
6153 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6157 all_blocks (tree block, tree *vector)
6163 TREE_ASM_WRITTEN (block) = 0;
6165 /* Record this block. */
6167 vector[n_blocks] = block;
6171 /* Record the subblocks, and their subblocks... */
6172 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6173 vector ? vector + n_blocks : 0);
6174 block = BLOCK_CHAIN (block);
6180 /* Return a vector containing all the blocks rooted at BLOCK. The
6181 number of elements in the vector is stored in N_BLOCKS_P. The
6182 vector is dynamically allocated; it is the caller's responsibility
6183 to call `free' on the pointer returned. */
6186 get_block_vector (tree block, int *n_blocks_p)
6190 *n_blocks_p = all_blocks (block, NULL);
6191 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
6192 all_blocks (block, block_vector);
6194 return block_vector;
6197 static GTY(()) int next_block_index = 2;
6199 /* Set BLOCK_NUMBER for all the blocks in FN. */
6202 number_blocks (tree fn)
6208 /* For SDB and XCOFF debugging output, we start numbering the blocks
6209 from 1 within each function, rather than keeping a running
6211 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6212 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6213 next_block_index = 1;
6216 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6218 /* The top-level BLOCK isn't numbered at all. */
6219 for (i = 1; i < n_blocks; ++i)
6220 /* We number the blocks from two. */
6221 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6223 free (block_vector);
6228 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6231 debug_find_var_in_block_tree (tree var, tree block)
6235 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6239 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6241 tree ret = debug_find_var_in_block_tree (var, t);
6249 /* Allocate a function structure and reset its contents to the defaults. */
6252 prepare_function_start (void)
6254 cfun = ggc_alloc_cleared (sizeof (struct function));
6256 init_stmt_for_function ();
6257 init_eh_for_function ();
6259 cse_not_expected = ! optimize;
6261 /* Caller save not needed yet. */
6262 caller_save_needed = 0;
6264 /* No stack slots have been made yet. */
6265 stack_slot_list = 0;
6267 current_function_has_nonlocal_label = 0;
6268 current_function_has_nonlocal_goto = 0;
6270 /* There is no stack slot for handling nonlocal gotos. */
6271 nonlocal_goto_handler_slots = 0;
6272 nonlocal_goto_stack_level = 0;
6274 /* No labels have been declared for nonlocal use. */
6275 nonlocal_labels = 0;
6276 nonlocal_goto_handler_labels = 0;
6278 /* No function calls so far in this function. */
6279 function_call_count = 0;
6281 /* No parm regs have been allocated.
6282 (This is important for output_inline_function.) */
6283 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6285 /* Initialize the RTL mechanism. */
6288 /* Initialize the queue of pending postincrement and postdecrements,
6289 and some other info in expr.c. */
6292 /* We haven't done register allocation yet. */
6295 init_varasm_status (cfun);
6297 /* Clear out data used for inlining. */
6298 cfun->inlinable = 0;
6299 cfun->original_decl_initial = 0;
6300 cfun->original_arg_vector = 0;
6302 cfun->stack_alignment_needed = STACK_BOUNDARY;
6303 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6305 /* Set if a call to setjmp is seen. */
6306 current_function_calls_setjmp = 0;
6308 /* Set if a call to longjmp is seen. */
6309 current_function_calls_longjmp = 0;
6311 current_function_calls_alloca = 0;
6312 current_function_calls_eh_return = 0;
6313 current_function_calls_constant_p = 0;
6314 current_function_contains_functions = 0;
6315 current_function_is_leaf = 0;
6316 current_function_nothrow = 0;
6317 current_function_sp_is_unchanging = 0;
6318 current_function_uses_only_leaf_regs = 0;
6319 current_function_has_computed_jump = 0;
6320 current_function_is_thunk = 0;
6322 current_function_returns_pcc_struct = 0;
6323 current_function_returns_struct = 0;
6324 current_function_epilogue_delay_list = 0;
6325 current_function_uses_const_pool = 0;
6326 current_function_uses_pic_offset_table = 0;
6327 current_function_cannot_inline = 0;
6329 /* We have not yet needed to make a label to jump to for tail-recursion. */
6330 tail_recursion_label = 0;
6332 /* We haven't had a need to make a save area for ap yet. */
6333 arg_pointer_save_area = 0;
6335 /* No stack slots allocated yet. */
6338 /* No SAVE_EXPRs in this function yet. */
6341 /* No RTL_EXPRs in this function yet. */
6344 /* Set up to allocate temporaries. */
6347 /* Indicate that we need to distinguish between the return value of the
6348 present function and the return value of a function being called. */
6349 rtx_equal_function_value_matters = 1;
6351 /* Indicate that we have not instantiated virtual registers yet. */
6352 virtuals_instantiated = 0;
6354 /* Indicate that we want CONCATs now. */
6355 generating_concat_p = 1;
6357 /* Indicate we have no need of a frame pointer yet. */
6358 frame_pointer_needed = 0;
6360 /* By default assume not stdarg. */
6361 current_function_stdarg = 0;
6363 /* We haven't made any trampolines for this function yet. */
6364 trampoline_list = 0;
6366 init_pending_stack_adjust ();
6367 inhibit_defer_pop = 0;
6369 current_function_outgoing_args_size = 0;
6371 current_function_funcdef_no = funcdef_no++;
6373 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6375 cfun->max_jumptable_ents = 0;
6377 (*lang_hooks.function.init) (cfun);
6378 if (init_machine_status)
6379 cfun->machine = (*init_machine_status) ();
6382 /* Initialize the rtl expansion mechanism so that we can do simple things
6383 like generate sequences. This is used to provide a context during global
6384 initialization of some passes. */
6386 init_dummy_function_start (void)
6388 prepare_function_start ();
6391 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6392 and initialize static variables for generating RTL for the statements
6396 init_function_start (tree subr)
6398 prepare_function_start ();
6400 current_function_name = (*lang_hooks.decl_printable_name) (subr, 2);
6403 /* Nonzero if this is a nested function that uses a static chain. */
6405 current_function_needs_context
6406 = (decl_function_context (current_function_decl) != 0
6407 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6409 /* Within function body, compute a type's size as soon it is laid out. */
6410 immediate_size_expand++;
6412 /* Prevent ever trying to delete the first instruction of a
6413 function. Also tell final how to output a linenum before the
6414 function prologue. Note linenums could be missing, e.g. when
6415 compiling a Java .class file. */
6416 if (DECL_SOURCE_LINE (subr))
6417 emit_line_note (DECL_SOURCE_LOCATION (subr));
6419 /* Make sure first insn is a note even if we don't want linenums.
6420 This makes sure the first insn will never be deleted.
6421 Also, final expects a note to appear there. */
6422 emit_note (NOTE_INSN_DELETED);
6424 /* Set flags used by final.c. */
6425 if (aggregate_value_p (DECL_RESULT (subr)))
6427 #ifdef PCC_STATIC_STRUCT_RETURN
6428 current_function_returns_pcc_struct = 1;
6430 current_function_returns_struct = 1;
6433 /* Warn if this value is an aggregate type,
6434 regardless of which calling convention we are using for it. */
6435 if (warn_aggregate_return
6436 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6437 warning ("function returns an aggregate");
6439 current_function_returns_pointer
6440 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6443 /* Make sure all values used by the optimization passes have sane
6446 init_function_for_compilation (void)
6450 /* No prologue/epilogue insns yet. */
6451 VARRAY_GROW (prologue, 0);
6452 VARRAY_GROW (epilogue, 0);
6453 VARRAY_GROW (sibcall_epilogue, 0);
6456 /* Expand a call to __main at the beginning of a possible main function. */
6458 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6459 #undef HAS_INIT_SECTION
6460 #define HAS_INIT_SECTION
6464 expand_main_function (void)
6466 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6467 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6469 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6473 /* Forcibly align the stack. */
6474 #ifdef STACK_GROWS_DOWNWARD
6475 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6476 stack_pointer_rtx, 1, OPTAB_WIDEN);
6478 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6479 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6480 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6481 stack_pointer_rtx, 1, OPTAB_WIDEN);
6483 if (tmp != stack_pointer_rtx)
6484 emit_move_insn (stack_pointer_rtx, tmp);
6486 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6487 tmp = force_reg (Pmode, const0_rtx);
6488 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6492 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6493 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6496 emit_insn_before (seq, tmp);
6502 #ifndef HAS_INIT_SECTION
6503 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6507 /* The PENDING_SIZES represent the sizes of variable-sized types.
6508 Create RTL for the various sizes now (using temporary variables),
6509 so that we can refer to the sizes from the RTL we are generating
6510 for the current function. The PENDING_SIZES are a TREE_LIST. The
6511 TREE_VALUE of each node is a SAVE_EXPR. */
6514 expand_pending_sizes (tree pending_sizes)
6518 /* Evaluate now the sizes of any types declared among the arguments. */
6519 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6521 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6522 /* Flush the queue in case this parameter declaration has
6528 /* Start the RTL for a new function, and set variables used for
6530 SUBR is the FUNCTION_DECL node.
6531 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6532 the function's parameters, which must be run at any return statement. */
6535 expand_function_start (tree subr, int parms_have_cleanups)
6538 rtx last_ptr = NULL_RTX;
6540 /* Make sure volatile mem refs aren't considered
6541 valid operands of arithmetic insns. */
6542 init_recog_no_volatile ();
6544 current_function_instrument_entry_exit
6545 = (flag_instrument_function_entry_exit
6546 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6548 current_function_profile
6550 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6552 current_function_limit_stack
6553 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6555 /* If function gets a static chain arg, store it in the stack frame.
6556 Do this first, so it gets the first stack slot offset. */
6557 if (current_function_needs_context)
6559 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6561 /* Delay copying static chain if it is not a register to avoid
6562 conflicts with regs used for parameters. */
6563 if (! SMALL_REGISTER_CLASSES
6564 || GET_CODE (static_chain_incoming_rtx) == REG)
6565 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6568 /* If the parameters of this function need cleaning up, get a label
6569 for the beginning of the code which executes those cleanups. This must
6570 be done before doing anything with return_label. */
6571 if (parms_have_cleanups)
6572 cleanup_label = gen_label_rtx ();
6576 /* Make the label for return statements to jump to. Do not special
6577 case machines with special return instructions -- they will be
6578 handled later during jump, ifcvt, or epilogue creation. */
6579 return_label = gen_label_rtx ();
6581 /* Initialize rtx used to return the value. */
6582 /* Do this before assign_parms so that we copy the struct value address
6583 before any library calls that assign parms might generate. */
6585 /* Decide whether to return the value in memory or in a register. */
6586 if (aggregate_value_p (DECL_RESULT (subr)))
6588 /* Returning something that won't go in a register. */
6589 rtx value_address = 0;
6591 #ifdef PCC_STATIC_STRUCT_RETURN
6592 if (current_function_returns_pcc_struct)
6594 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6595 value_address = assemble_static_space (size);
6600 /* Expect to be passed the address of a place to store the value.
6601 If it is passed as an argument, assign_parms will take care of
6603 if (struct_value_incoming_rtx)
6605 value_address = gen_reg_rtx (Pmode);
6606 emit_move_insn (value_address, struct_value_incoming_rtx);
6611 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6612 set_mem_attributes (x, DECL_RESULT (subr), 1);
6613 SET_DECL_RTL (DECL_RESULT (subr), x);
6616 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6617 /* If return mode is void, this decl rtl should not be used. */
6618 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6621 /* Compute the return values into a pseudo reg, which we will copy
6622 into the true return register after the cleanups are done. */
6624 /* In order to figure out what mode to use for the pseudo, we
6625 figure out what the mode of the eventual return register will
6626 actually be, and use that. */
6628 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6631 /* Structures that are returned in registers are not aggregate_value_p,
6632 so we may see a PARALLEL or a REG. */
6633 if (REG_P (hard_reg))
6634 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6635 else if (GET_CODE (hard_reg) == PARALLEL)
6636 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6640 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6641 result to the real return register(s). */
6642 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6645 /* Initialize rtx for parameters and local variables.
6646 In some cases this requires emitting insns. */
6648 assign_parms (subr);
6650 /* Copy the static chain now if it wasn't a register. The delay is to
6651 avoid conflicts with the parameter passing registers. */
6653 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6654 if (GET_CODE (static_chain_incoming_rtx) != REG)
6655 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6657 /* The following was moved from init_function_start.
6658 The move is supposed to make sdb output more accurate. */
6659 /* Indicate the beginning of the function body,
6660 as opposed to parm setup. */
6661 emit_note (NOTE_INSN_FUNCTION_BEG);
6663 if (GET_CODE (get_last_insn ()) != NOTE)
6664 emit_note (NOTE_INSN_DELETED);
6665 parm_birth_insn = get_last_insn ();
6667 context_display = 0;
6668 if (current_function_needs_context)
6670 /* Fetch static chain values for containing functions. */
6671 tem = decl_function_context (current_function_decl);
6672 /* Copy the static chain pointer into a pseudo. If we have
6673 small register classes, copy the value from memory if
6674 static_chain_incoming_rtx is a REG. */
6677 /* If the static chain originally came in a register, put it back
6678 there, then move it out in the next insn. The reason for
6679 this peculiar code is to satisfy function integration. */
6680 if (SMALL_REGISTER_CLASSES
6681 && GET_CODE (static_chain_incoming_rtx) == REG)
6682 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6683 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6688 tree rtlexp = make_node (RTL_EXPR);
6690 RTL_EXPR_RTL (rtlexp) = last_ptr;
6691 context_display = tree_cons (tem, rtlexp, context_display);
6692 tem = decl_function_context (tem);
6695 /* Chain thru stack frames, assuming pointer to next lexical frame
6696 is found at the place we always store it. */
6697 #ifdef FRAME_GROWS_DOWNWARD
6698 last_ptr = plus_constant (last_ptr,
6699 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6701 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6702 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6703 last_ptr = copy_to_reg (last_ptr);
6705 /* If we are not optimizing, ensure that we know that this
6706 piece of context is live over the entire function. */
6708 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6713 if (current_function_instrument_entry_exit)
6715 rtx fun = DECL_RTL (current_function_decl);
6716 if (GET_CODE (fun) == MEM)
6717 fun = XEXP (fun, 0);
6720 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6722 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6724 hard_frame_pointer_rtx),
6728 if (current_function_profile)
6731 PROFILE_HOOK (current_function_funcdef_no);
6735 /* After the display initializations is where the tail-recursion label
6736 should go, if we end up needing one. Ensure we have a NOTE here
6737 since some things (like trampolines) get placed before this. */
6738 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
6740 /* Evaluate now the sizes of any types declared among the arguments. */
6741 expand_pending_sizes (nreverse (get_pending_sizes ()));
6743 /* Make sure there is a line number after the function entry setup code. */
6744 force_next_line_note ();
6747 /* Undo the effects of init_dummy_function_start. */
6749 expand_dummy_function_end (void)
6751 /* End any sequences that failed to be closed due to syntax errors. */
6752 while (in_sequence_p ())
6755 /* Outside function body, can't compute type's actual size
6756 until next function's body starts. */
6758 free_after_parsing (cfun);
6759 free_after_compilation (cfun);
6763 /* Call DOIT for each hard register used as a return value from
6764 the current function. */
6767 diddle_return_value (void (*doit) (rtx, void *), void *arg)
6769 rtx outgoing = current_function_return_rtx;
6774 if (GET_CODE (outgoing) == REG)
6775 (*doit) (outgoing, arg);
6776 else if (GET_CODE (outgoing) == PARALLEL)
6780 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6782 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6784 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6791 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6793 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6797 clobber_return_register (void)
6799 diddle_return_value (do_clobber_return_reg, NULL);
6801 /* In case we do use pseudo to return value, clobber it too. */
6802 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6804 tree decl_result = DECL_RESULT (current_function_decl);
6805 rtx decl_rtl = DECL_RTL (decl_result);
6806 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6808 do_clobber_return_reg (decl_rtl, NULL);
6814 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6816 emit_insn (gen_rtx_USE (VOIDmode, reg));
6820 use_return_register (void)
6822 diddle_return_value (do_use_return_reg, NULL);
6825 static GTY(()) rtx initial_trampoline;
6827 /* Generate RTL for the end of the current function. */
6830 expand_function_end (void)
6835 finish_expr_for_function ();
6837 /* If arg_pointer_save_area was referenced only from a nested
6838 function, we will not have initialized it yet. Do that now. */
6839 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6840 get_arg_pointer_save_area (cfun);
6842 #ifdef NON_SAVING_SETJMP
6843 /* Don't put any variables in registers if we call setjmp
6844 on a machine that fails to restore the registers. */
6845 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6847 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6848 setjmp_protect (DECL_INITIAL (current_function_decl));
6850 setjmp_protect_args ();
6854 /* Initialize any trampolines required by this function. */
6855 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6857 tree function = TREE_PURPOSE (link);
6858 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6859 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6860 #ifdef TRAMPOLINE_TEMPLATE
6865 #ifdef TRAMPOLINE_TEMPLATE
6866 /* First make sure this compilation has a template for
6867 initializing trampolines. */
6868 if (initial_trampoline == 0)
6871 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6872 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6876 /* Generate insns to initialize the trampoline. */
6878 tramp = round_trampoline_addr (XEXP (tramp, 0));
6879 #ifdef TRAMPOLINE_TEMPLATE
6880 blktramp = replace_equiv_address (initial_trampoline, tramp);
6881 emit_block_move (blktramp, initial_trampoline,
6882 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6884 trampolines_created = 1;
6885 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6889 /* Put those insns at entry to the containing function (this one). */
6890 emit_insn_before (seq, tail_recursion_reentry);
6893 /* If we are doing stack checking and this function makes calls,
6894 do a stack probe at the start of the function to ensure we have enough
6895 space for another stack frame. */
6896 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6900 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6901 if (GET_CODE (insn) == CALL_INSN)
6904 probe_stack_range (STACK_CHECK_PROTECT,
6905 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6908 emit_insn_before (seq, tail_recursion_reentry);
6913 /* Possibly warn about unused parameters. */
6914 if (warn_unused_parameter)
6918 for (decl = DECL_ARGUMENTS (current_function_decl);
6919 decl; decl = TREE_CHAIN (decl))
6920 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6921 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6922 warning_with_decl (decl, "unused parameter `%s'");
6925 /* Delete handlers for nonlocal gotos if nothing uses them. */
6926 if (nonlocal_goto_handler_slots != 0
6927 && ! current_function_has_nonlocal_label)
6930 /* End any sequences that failed to be closed due to syntax errors. */
6931 while (in_sequence_p ())
6934 /* Outside function body, can't compute type's actual size
6935 until next function's body starts. */
6936 immediate_size_expand--;
6938 clear_pending_stack_adjust ();
6939 do_pending_stack_adjust ();
6941 /* Mark the end of the function body.
6942 If control reaches this insn, the function can drop through
6943 without returning a value. */
6944 emit_note (NOTE_INSN_FUNCTION_END);
6946 /* Must mark the last line number note in the function, so that the test
6947 coverage code can avoid counting the last line twice. This just tells
6948 the code to ignore the immediately following line note, since there
6949 already exists a copy of this note somewhere above. This line number
6950 note is still needed for debugging though, so we can't delete it. */
6951 if (flag_test_coverage)
6952 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
6954 /* Output a linenumber for the end of the function.
6955 SDB depends on this. */
6956 force_next_line_note ();
6957 emit_line_note (input_location);
6959 /* Before the return label (if any), clobber the return
6960 registers so that they are not propagated live to the rest of
6961 the function. This can only happen with functions that drop
6962 through; if there had been a return statement, there would
6963 have either been a return rtx, or a jump to the return label.
6965 We delay actual code generation after the current_function_value_rtx
6967 clobber_after = get_last_insn ();
6969 /* Output the label for the actual return from the function,
6970 if one is expected. This happens either because a function epilogue
6971 is used instead of a return instruction, or because a return was done
6972 with a goto in order to run local cleanups, or because of pcc-style
6973 structure returning. */
6975 emit_label (return_label);
6977 if (current_function_instrument_entry_exit)
6979 rtx fun = DECL_RTL (current_function_decl);
6980 if (GET_CODE (fun) == MEM)
6981 fun = XEXP (fun, 0);
6984 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6986 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6988 hard_frame_pointer_rtx),
6992 /* Let except.c know where it should emit the call to unregister
6993 the function context for sjlj exceptions. */
6994 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6995 sjlj_emit_function_exit_after (get_last_insn ());
6997 /* If we had calls to alloca, and this machine needs
6998 an accurate stack pointer to exit the function,
6999 insert some code to save and restore the stack pointer. */
7000 #ifdef EXIT_IGNORE_STACK
7001 if (! EXIT_IGNORE_STACK)
7003 if (current_function_calls_alloca)
7007 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
7008 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
7011 /* If scalar return value was computed in a pseudo-reg, or was a named
7012 return value that got dumped to the stack, copy that to the hard
7014 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
7016 tree decl_result = DECL_RESULT (current_function_decl);
7017 rtx decl_rtl = DECL_RTL (decl_result);
7019 if (REG_P (decl_rtl)
7020 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
7021 : DECL_REGISTER (decl_result))
7023 rtx real_decl_rtl = current_function_return_rtx;
7025 /* This should be set in assign_parms. */
7026 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
7029 /* If this is a BLKmode structure being returned in registers,
7030 then use the mode computed in expand_return. Note that if
7031 decl_rtl is memory, then its mode may have been changed,
7032 but that current_function_return_rtx has not. */
7033 if (GET_MODE (real_decl_rtl) == BLKmode)
7034 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
7036 /* If a named return value dumped decl_return to memory, then
7037 we may need to re-do the PROMOTE_MODE signed/unsigned
7039 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
7041 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
7043 #ifdef PROMOTE_FUNCTION_RETURN
7044 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7048 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7050 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7052 /* If expand_function_start has created a PARALLEL for decl_rtl,
7053 move the result to the real return registers. Otherwise, do
7054 a group load from decl_rtl for a named return. */
7055 if (GET_CODE (decl_rtl) == PARALLEL)
7056 emit_group_move (real_decl_rtl, decl_rtl);
7058 emit_group_load (real_decl_rtl, decl_rtl,
7059 TREE_TYPE (decl_result),
7060 int_size_in_bytes (TREE_TYPE (decl_result)));
7063 emit_move_insn (real_decl_rtl, decl_rtl);
7067 /* If returning a structure, arrange to return the address of the value
7068 in a place where debuggers expect to find it.
7070 If returning a structure PCC style,
7071 the caller also depends on this value.
7072 And current_function_returns_pcc_struct is not necessarily set. */
7073 if (current_function_returns_struct
7074 || current_function_returns_pcc_struct)
7077 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7078 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7079 #ifdef FUNCTION_OUTGOING_VALUE
7081 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7082 current_function_decl);
7085 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7088 /* Mark this as a function return value so integrate will delete the
7089 assignment and USE below when inlining this function. */
7090 REG_FUNCTION_VALUE_P (outgoing) = 1;
7092 #ifdef POINTERS_EXTEND_UNSIGNED
7093 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7094 if (GET_MODE (outgoing) != GET_MODE (value_address))
7095 value_address = convert_memory_address (GET_MODE (outgoing),
7099 emit_move_insn (outgoing, value_address);
7101 /* Show return register used to hold result (in this case the address
7103 current_function_return_rtx = outgoing;
7106 /* If this is an implementation of throw, do what's necessary to
7107 communicate between __builtin_eh_return and the epilogue. */
7108 expand_eh_return ();
7110 /* Emit the actual code to clobber return register. */
7115 clobber_return_register ();
7119 after = emit_insn_after (seq, clobber_after);
7121 if (clobber_after != after)
7122 cfun->x_clobber_return_insn = after;
7125 /* ??? This should no longer be necessary since stupid is no longer with
7126 us, but there are some parts of the compiler (eg reload_combine, and
7127 sh mach_dep_reorg) that still try and compute their own lifetime info
7128 instead of using the general framework. */
7129 use_return_register ();
7131 /* Fix up any gotos that jumped out to the outermost
7132 binding level of the function.
7133 Must follow emitting RETURN_LABEL. */
7135 /* If you have any cleanups to do at this point,
7136 and they need to create temporary variables,
7137 then you will lose. */
7138 expand_fixups (get_insns ());
7142 get_arg_pointer_save_area (struct function *f)
7144 rtx ret = f->x_arg_pointer_save_area;
7148 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7149 f->x_arg_pointer_save_area = ret;
7152 if (f == cfun && ! f->arg_pointer_save_area_init)
7156 /* Save the arg pointer at the beginning of the function. The
7157 generated stack slot may not be a valid memory address, so we
7158 have to check it and fix it if necessary. */
7160 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7164 push_topmost_sequence ();
7165 emit_insn_after (seq, get_insns ());
7166 pop_topmost_sequence ();
7172 /* Extend a vector that records the INSN_UIDs of INSNS
7173 (a list of one or more insns). */
7176 record_insns (rtx insns, varray_type *vecp)
7183 while (tmp != NULL_RTX)
7186 tmp = NEXT_INSN (tmp);
7189 i = VARRAY_SIZE (*vecp);
7190 VARRAY_GROW (*vecp, i + len);
7192 while (tmp != NULL_RTX)
7194 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7196 tmp = NEXT_INSN (tmp);
7200 /* Set the specified locator to the insn chain. */
7202 set_insn_locators (rtx insn, int loc)
7204 while (insn != NULL_RTX)
7207 INSN_LOCATOR (insn) = loc;
7208 insn = NEXT_INSN (insn);
7212 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7213 be running after reorg, SEQUENCE rtl is possible. */
7216 contains (rtx insn, varray_type vec)
7220 if (GET_CODE (insn) == INSN
7221 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7224 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7225 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7226 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7232 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7233 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7240 prologue_epilogue_contains (rtx insn)
7242 if (contains (insn, prologue))
7244 if (contains (insn, epilogue))
7250 sibcall_epilogue_contains (rtx insn)
7252 if (sibcall_epilogue)
7253 return contains (insn, sibcall_epilogue);
7258 /* Insert gen_return at the end of block BB. This also means updating
7259 block_for_insn appropriately. */
7262 emit_return_into_block (basic_block bb, rtx line_note)
7264 emit_jump_insn_after (gen_return (), bb->end);
7266 emit_note_copy_after (line_note, PREV_INSN (bb->end));
7268 #endif /* HAVE_return */
7270 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7272 /* These functions convert the epilogue into a variant that does not modify the
7273 stack pointer. This is used in cases where a function returns an object
7274 whose size is not known until it is computed. The called function leaves the
7275 object on the stack, leaves the stack depressed, and returns a pointer to
7278 What we need to do is track all modifications and references to the stack
7279 pointer, deleting the modifications and changing the references to point to
7280 the location the stack pointer would have pointed to had the modifications
7283 These functions need to be portable so we need to make as few assumptions
7284 about the epilogue as we can. However, the epilogue basically contains
7285 three things: instructions to reset the stack pointer, instructions to
7286 reload registers, possibly including the frame pointer, and an
7287 instruction to return to the caller.
7289 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7290 We also make no attempt to validate the insns we make since if they are
7291 invalid, we probably can't do anything valid. The intent is that these
7292 routines get "smarter" as more and more machines start to use them and
7293 they try operating on different epilogues.
7295 We use the following structure to track what the part of the epilogue that
7296 we've already processed has done. We keep two copies of the SP equivalence,
7297 one for use during the insn we are processing and one for use in the next
7298 insn. The difference is because one part of a PARALLEL may adjust SP
7299 and the other may use it. */
7303 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7304 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7305 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7306 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7307 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7308 should be set to once we no longer need
7312 static void handle_epilogue_set (rtx, struct epi_info *);
7313 static void emit_equiv_load (struct epi_info *);
7315 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7316 no modifications to the stack pointer. Return the new list of insns. */
7319 keep_stack_depressed (rtx insns)
7322 struct epi_info info;
7325 /* If the epilogue is just a single instruction, it ust be OK as is. */
7327 if (NEXT_INSN (insns) == NULL_RTX)
7330 /* Otherwise, start a sequence, initialize the information we have, and
7331 process all the insns we were given. */
7334 info.sp_equiv_reg = stack_pointer_rtx;
7336 info.equiv_reg_src = 0;
7340 while (insn != NULL_RTX)
7342 next = NEXT_INSN (insn);
7351 /* If this insn references the register that SP is equivalent to and
7352 we have a pending load to that register, we must force out the load
7353 first and then indicate we no longer know what SP's equivalent is. */
7354 if (info.equiv_reg_src != 0
7355 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7357 emit_equiv_load (&info);
7358 info.sp_equiv_reg = 0;
7361 info.new_sp_equiv_reg = info.sp_equiv_reg;
7362 info.new_sp_offset = info.sp_offset;
7364 /* If this is a (RETURN) and the return address is on the stack,
7365 update the address and change to an indirect jump. */
7366 if (GET_CODE (PATTERN (insn)) == RETURN
7367 || (GET_CODE (PATTERN (insn)) == PARALLEL
7368 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7370 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7372 HOST_WIDE_INT offset = 0;
7373 rtx jump_insn, jump_set;
7375 /* If the return address is in a register, we can emit the insn
7376 unchanged. Otherwise, it must be a MEM and we see what the
7377 base register and offset are. In any case, we have to emit any
7378 pending load to the equivalent reg of SP, if any. */
7379 if (GET_CODE (retaddr) == REG)
7381 emit_equiv_load (&info);
7386 else if (GET_CODE (retaddr) == MEM
7387 && GET_CODE (XEXP (retaddr, 0)) == REG)
7388 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7389 else if (GET_CODE (retaddr) == MEM
7390 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7391 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7392 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7394 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7395 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7400 /* If the base of the location containing the return pointer
7401 is SP, we must update it with the replacement address. Otherwise,
7402 just build the necessary MEM. */
7403 retaddr = plus_constant (base, offset);
7404 if (base == stack_pointer_rtx)
7405 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7406 plus_constant (info.sp_equiv_reg,
7409 retaddr = gen_rtx_MEM (Pmode, retaddr);
7411 /* If there is a pending load to the equivalent register for SP
7412 and we reference that register, we must load our address into
7413 a scratch register and then do that load. */
7414 if (info.equiv_reg_src
7415 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7420 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7421 if (HARD_REGNO_MODE_OK (regno, Pmode)
7422 && !fixed_regs[regno]
7423 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7424 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7426 && !refers_to_regno_p (regno,
7427 regno + HARD_REGNO_NREGS (regno,
7429 info.equiv_reg_src, NULL))
7432 if (regno == FIRST_PSEUDO_REGISTER)
7435 reg = gen_rtx_REG (Pmode, regno);
7436 emit_move_insn (reg, retaddr);
7440 emit_equiv_load (&info);
7441 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7443 /* Show the SET in the above insn is a RETURN. */
7444 jump_set = single_set (jump_insn);
7448 SET_IS_RETURN_P (jump_set) = 1;
7451 /* If SP is not mentioned in the pattern and its equivalent register, if
7452 any, is not modified, just emit it. Otherwise, if neither is set,
7453 replace the reference to SP and emit the insn. If none of those are
7454 true, handle each SET individually. */
7455 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7456 && (info.sp_equiv_reg == stack_pointer_rtx
7457 || !reg_set_p (info.sp_equiv_reg, insn)))
7459 else if (! reg_set_p (stack_pointer_rtx, insn)
7460 && (info.sp_equiv_reg == stack_pointer_rtx
7461 || !reg_set_p (info.sp_equiv_reg, insn)))
7463 if (! validate_replace_rtx (stack_pointer_rtx,
7464 plus_constant (info.sp_equiv_reg,
7471 else if (GET_CODE (PATTERN (insn)) == SET)
7472 handle_epilogue_set (PATTERN (insn), &info);
7473 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7475 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7476 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7477 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7482 info.sp_equiv_reg = info.new_sp_equiv_reg;
7483 info.sp_offset = info.new_sp_offset;
7488 insns = get_insns ();
7493 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7494 structure that contains information about what we've seen so far. We
7495 process this SET by either updating that data or by emitting one or
7499 handle_epilogue_set (rtx set, struct epi_info *p)
7501 /* First handle the case where we are setting SP. Record what it is being
7502 set from. If unknown, abort. */
7503 if (reg_set_p (stack_pointer_rtx, set))
7505 if (SET_DEST (set) != stack_pointer_rtx)
7508 if (GET_CODE (SET_SRC (set)) == PLUS
7509 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7511 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7512 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7515 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7517 /* If we are adjusting SP, we adjust from the old data. */
7518 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7520 p->new_sp_equiv_reg = p->sp_equiv_reg;
7521 p->new_sp_offset += p->sp_offset;
7524 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7530 /* Next handle the case where we are setting SP's equivalent register.
7531 If we already have a value to set it to, abort. We could update, but
7532 there seems little point in handling that case. Note that we have
7533 to allow for the case where we are setting the register set in
7534 the previous part of a PARALLEL inside a single insn. But use the
7535 old offset for any updates within this insn. */
7536 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7538 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7539 || p->equiv_reg_src != 0)
7543 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7544 plus_constant (p->sp_equiv_reg,
7548 /* Otherwise, replace any references to SP in the insn to its new value
7549 and emit the insn. */
7552 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7553 plus_constant (p->sp_equiv_reg,
7555 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7556 plus_constant (p->sp_equiv_reg,
7562 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7565 emit_equiv_load (struct epi_info *p)
7567 if (p->equiv_reg_src != 0)
7568 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7570 p->equiv_reg_src = 0;
7574 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7575 this into place with notes indicating where the prologue ends and where
7576 the epilogue begins. Update the basic block information when possible. */
7579 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
7583 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7586 #ifdef HAVE_prologue
7587 rtx prologue_end = NULL_RTX;
7589 #if defined (HAVE_epilogue) || defined(HAVE_return)
7590 rtx epilogue_end = NULL_RTX;
7593 #ifdef HAVE_prologue
7597 seq = gen_prologue ();
7600 /* Retain a map of the prologue insns. */
7601 record_insns (seq, &prologue);
7602 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
7606 set_insn_locators (seq, prologue_locator);
7608 /* Can't deal with multiple successors of the entry block
7609 at the moment. Function should always have at least one
7611 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7614 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7619 /* If the exit block has no non-fake predecessors, we don't need
7621 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7622 if ((e->flags & EDGE_FAKE) == 0)
7628 if (optimize && HAVE_return)
7630 /* If we're allowed to generate a simple return instruction,
7631 then by definition we don't need a full epilogue. Examine
7632 the block that falls through to EXIT. If it does not
7633 contain any code, examine its predecessors and try to
7634 emit (conditional) return instructions. */
7640 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7641 if (e->flags & EDGE_FALLTHRU)
7647 /* Verify that there are no active instructions in the last block. */
7649 while (label && GET_CODE (label) != CODE_LABEL)
7651 if (active_insn_p (label))
7653 label = PREV_INSN (label);
7656 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7658 rtx epilogue_line_note = NULL_RTX;
7660 /* Locate the line number associated with the closing brace,
7661 if we can find one. */
7662 for (seq = get_last_insn ();
7663 seq && ! active_insn_p (seq);
7664 seq = PREV_INSN (seq))
7665 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7667 epilogue_line_note = seq;
7671 for (e = last->pred; e; e = e_next)
7673 basic_block bb = e->src;
7676 e_next = e->pred_next;
7677 if (bb == ENTRY_BLOCK_PTR)
7681 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7684 /* If we have an unconditional jump, we can replace that
7685 with a simple return instruction. */
7686 if (simplejump_p (jump))
7688 emit_return_into_block (bb, epilogue_line_note);
7692 /* If we have a conditional jump, we can try to replace
7693 that with a conditional return instruction. */
7694 else if (condjump_p (jump))
7696 if (! redirect_jump (jump, 0, 0))
7699 /* If this block has only one successor, it both jumps
7700 and falls through to the fallthru block, so we can't
7702 if (bb->succ->succ_next == NULL)
7708 /* Fix up the CFG for the successful change we just made. */
7709 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7712 /* Emit a return insn for the exit fallthru block. Whether
7713 this is still reachable will be determined later. */
7715 emit_barrier_after (last->end);
7716 emit_return_into_block (last, epilogue_line_note);
7717 epilogue_end = last->end;
7718 last->succ->flags &= ~EDGE_FALLTHRU;
7723 #ifdef HAVE_epilogue
7726 /* Find the edge that falls through to EXIT. Other edges may exist
7727 due to RETURN instructions, but those don't need epilogues.
7728 There really shouldn't be a mixture -- either all should have
7729 been converted or none, however... */
7731 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7732 if (e->flags & EDGE_FALLTHRU)
7738 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
7740 seq = gen_epilogue ();
7742 #ifdef INCOMING_RETURN_ADDR_RTX
7743 /* If this function returns with the stack depressed and we can support
7744 it, massage the epilogue to actually do that. */
7745 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7746 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7747 seq = keep_stack_depressed (seq);
7750 emit_jump_insn (seq);
7752 /* Retain a map of the epilogue insns. */
7753 record_insns (seq, &epilogue);
7754 set_insn_locators (seq, epilogue_locator);
7759 insert_insn_on_edge (seq, e);
7766 commit_edge_insertions ();
7768 #ifdef HAVE_sibcall_epilogue
7769 /* Emit sibling epilogues before any sibling call sites. */
7770 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7772 basic_block bb = e->src;
7777 if (GET_CODE (insn) != CALL_INSN
7778 || ! SIBLING_CALL_P (insn))
7782 emit_insn (gen_sibcall_epilogue ());
7786 /* Retain a map of the epilogue insns. Used in life analysis to
7787 avoid getting rid of sibcall epilogue insns. Do this before we
7788 actually emit the sequence. */
7789 record_insns (seq, &sibcall_epilogue);
7790 set_insn_locators (seq, epilogue_locator);
7792 i = PREV_INSN (insn);
7793 newinsn = emit_insn_before (seq, insn);
7797 #ifdef HAVE_prologue
7802 /* GDB handles `break f' by setting a breakpoint on the first
7803 line note after the prologue. Which means (1) that if
7804 there are line number notes before where we inserted the
7805 prologue we should move them, and (2) we should generate a
7806 note before the end of the first basic block, if there isn't
7809 ??? This behavior is completely broken when dealing with
7810 multiple entry functions. We simply place the note always
7811 into first basic block and let alternate entry points
7815 for (insn = prologue_end; insn; insn = prev)
7817 prev = PREV_INSN (insn);
7818 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7820 /* Note that we cannot reorder the first insn in the
7821 chain, since rest_of_compilation relies on that
7822 remaining constant. */
7825 reorder_insns (insn, insn, prologue_end);
7829 /* Find the last line number note in the first block. */
7830 for (insn = ENTRY_BLOCK_PTR->next_bb->end;
7831 insn != prologue_end && insn;
7832 insn = PREV_INSN (insn))
7833 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7836 /* If we didn't find one, make a copy of the first line number
7840 for (insn = next_active_insn (prologue_end);
7842 insn = PREV_INSN (insn))
7843 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7845 emit_note_copy_after (insn, prologue_end);
7851 #ifdef HAVE_epilogue
7856 /* Similarly, move any line notes that appear after the epilogue.
7857 There is no need, however, to be quite so anal about the existence
7859 for (insn = epilogue_end; insn; insn = next)
7861 next = NEXT_INSN (insn);
7862 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7863 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7869 /* Reposition the prologue-end and epilogue-begin notes after instruction
7870 scheduling and delayed branch scheduling. */
7873 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
7875 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7876 rtx insn, last, note;
7879 if ((len = VARRAY_SIZE (prologue)) > 0)
7883 /* Scan from the beginning until we reach the last prologue insn.
7884 We apparently can't depend on basic_block_{head,end} after
7886 for (insn = f; insn; insn = NEXT_INSN (insn))
7888 if (GET_CODE (insn) == NOTE)
7890 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7893 else if (contains (insn, prologue))
7903 /* Find the prologue-end note if we haven't already, and
7904 move it to just after the last prologue insn. */
7907 for (note = last; (note = NEXT_INSN (note));)
7908 if (GET_CODE (note) == NOTE
7909 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7913 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7914 if (GET_CODE (last) == CODE_LABEL)
7915 last = NEXT_INSN (last);
7916 reorder_insns (note, note, last);
7920 if ((len = VARRAY_SIZE (epilogue)) > 0)
7924 /* Scan from the end until we reach the first epilogue insn.
7925 We apparently can't depend on basic_block_{head,end} after
7927 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7929 if (GET_CODE (insn) == NOTE)
7931 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7934 else if (contains (insn, epilogue))
7944 /* Find the epilogue-begin note if we haven't already, and
7945 move it to just before the first epilogue insn. */
7948 for (note = insn; (note = PREV_INSN (note));)
7949 if (GET_CODE (note) == NOTE
7950 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7954 if (PREV_INSN (last) != note)
7955 reorder_insns (note, note, PREV_INSN (last));
7958 #endif /* HAVE_prologue or HAVE_epilogue */
7961 /* Called once, at initialization, to initialize function.c. */
7964 init_function_once (void)
7966 VARRAY_INT_INIT (prologue, 0, "prologue");
7967 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7968 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
7971 #include "gt-function.h"