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"
67 #ifndef TRAMPOLINE_ALIGNMENT
68 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
71 #ifndef LOCAL_ALIGNMENT
72 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
75 #ifndef STACK_ALIGNMENT_NEEDED
76 #define STACK_ALIGNMENT_NEEDED 1
79 /* Some systems use __main in a way incompatible with its use in gcc, in these
80 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
81 give the same symbol without quotes for an alternative entry point. You
82 must define both, or neither. */
84 #define NAME__MAIN "__main"
87 /* Round a value to the lowest integer less than it that is a multiple of
88 the required alignment. Avoid using division in case the value is
89 negative. Assume the alignment is a power of two. */
90 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
92 /* Similar, but round to the next highest integer that meets the
94 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
96 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
97 during rtl generation. If they are different register numbers, this is
98 always true. It may also be true if
99 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
100 generation. See fix_lexical_addr for details. */
102 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
103 #define NEED_SEPARATE_AP
106 /* Nonzero if function being compiled doesn't contain any calls
107 (ignoring the prologue and epilogue). This is set prior to
108 local register allocation and is valid for the remaining
110 int current_function_is_leaf;
112 /* Nonzero if function being compiled doesn't contain any instructions
113 that can throw an exception. This is set prior to final. */
115 int current_function_nothrow;
117 /* Nonzero if function being compiled doesn't modify the stack pointer
118 (ignoring the prologue and epilogue). This is only valid after
119 life_analysis has run. */
120 int current_function_sp_is_unchanging;
122 /* Nonzero if the function being compiled is a leaf function which only
123 uses leaf registers. This is valid after reload (specifically after
124 sched2) and is useful only if the port defines LEAF_REGISTERS. */
125 int current_function_uses_only_leaf_regs;
127 /* Nonzero once virtual register instantiation has been done.
128 assign_stack_local uses frame_pointer_rtx when this is nonzero.
129 calls.c:emit_library_call_value_1 uses it to set up
130 post-instantiation libcalls. */
131 int virtuals_instantiated;
133 /* Nonzero if at least one trampoline has been created. */
134 int trampolines_created;
136 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
137 static GTY(()) int funcdef_no;
139 /* These variables hold pointers to functions to create and destroy
140 target specific, per-function data structures. */
141 struct machine_function * (*init_machine_status) (void);
143 /* The FUNCTION_DECL for an inline function currently being expanded. */
144 tree inline_function_decl;
146 /* The currently compiled function. */
147 struct function *cfun = 0;
149 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
150 static GTY(()) varray_type prologue;
151 static GTY(()) varray_type epilogue;
153 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
155 static GTY(()) varray_type sibcall_epilogue;
157 /* In order to evaluate some expressions, such as function calls returning
158 structures in memory, we need to temporarily allocate stack locations.
159 We record each allocated temporary in the following structure.
161 Associated with each temporary slot is a nesting level. When we pop up
162 one level, all temporaries associated with the previous level are freed.
163 Normally, all temporaries are freed after the execution of the statement
164 in which they were created. However, if we are inside a ({...}) grouping,
165 the result may be in a temporary and hence must be preserved. If the
166 result could be in a temporary, we preserve it if we can determine which
167 one it is in. If we cannot determine which temporary may contain the
168 result, all temporaries are preserved. A temporary is preserved by
169 pretending it was allocated at the previous nesting level.
171 Automatic variables are also assigned temporary slots, at the nesting
172 level where they are defined. They are marked a "kept" so that
173 free_temp_slots will not free them. */
175 struct temp_slot GTY(())
177 /* Points to next temporary slot. */
178 struct temp_slot *next;
179 /* The rtx to used to reference the slot. */
181 /* The rtx used to represent the address if not the address of the
182 slot above. May be an EXPR_LIST if multiple addresses exist. */
184 /* The alignment (in bits) of the slot. */
186 /* The size, in units, of the slot. */
188 /* The type of the object in the slot, or zero if it doesn't correspond
189 to a type. We use this to determine whether a slot can be reused.
190 It can be reused if objects of the type of the new slot will always
191 conflict with objects of the type of the old slot. */
193 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
195 /* Nonzero if this temporary is currently in use. */
197 /* Nonzero if this temporary has its address taken. */
199 /* Nesting level at which this slot is being used. */
201 /* Nonzero if this should survive a call to free_temp_slots. */
203 /* The offset of the slot from the frame_pointer, including extra space
204 for alignment. This info is for combine_temp_slots. */
205 HOST_WIDE_INT base_offset;
206 /* The size of the slot, including extra space for alignment. This
207 info is for combine_temp_slots. */
208 HOST_WIDE_INT full_size;
211 /* This structure is used to record MEMs or pseudos used to replace VAR, any
212 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
213 maintain this list in case two operands of an insn were required to match;
214 in that case we must ensure we use the same replacement. */
216 struct fixup_replacement GTY(())
220 struct fixup_replacement *next;
223 struct insns_for_mem_entry
227 /* These are the INSNs which reference the MEM. */
231 /* Forward declarations. */
233 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int,
235 static struct temp_slot *find_temp_slot_from_address (rtx);
236 static void put_reg_into_stack (struct function *, rtx, tree, enum machine_mode,
237 enum machine_mode, int, unsigned int, int, htab_t);
238 static void schedule_fixup_var_refs (struct function *, rtx, tree, enum machine_mode,
240 static void fixup_var_refs (rtx, enum machine_mode, int, rtx, htab_t);
241 static struct fixup_replacement
242 *find_fixup_replacement (struct fixup_replacement **, rtx);
243 static void fixup_var_refs_insns (rtx, rtx, enum machine_mode, int, int, rtx);
244 static void fixup_var_refs_insns_with_hash (htab_t, rtx, enum machine_mode, int, rtx);
245 static void fixup_var_refs_insn (rtx, rtx, enum machine_mode, int, int, rtx);
246 static void fixup_var_refs_1 (rtx, enum machine_mode, rtx *, rtx,
247 struct fixup_replacement **, rtx);
248 static rtx fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
249 static rtx walk_fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
250 static rtx fixup_stack_1 (rtx, rtx);
251 static void optimize_bit_field (rtx, rtx, rtx *);
252 static void instantiate_decls (tree, int);
253 static void instantiate_decls_1 (tree, int);
254 static void instantiate_decl (rtx, HOST_WIDE_INT, int);
255 static rtx instantiate_new_reg (rtx, HOST_WIDE_INT *);
256 static int instantiate_virtual_regs_1 (rtx *, rtx, int);
257 static void delete_handlers (void);
258 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
259 static void pad_below (struct args_size *, enum machine_mode, tree);
260 static rtx round_trampoline_addr (rtx);
261 static rtx adjust_trampoline_addr (rtx);
262 static tree *identify_blocks_1 (rtx, tree *, tree *, tree *);
263 static void reorder_blocks_0 (tree);
264 static void reorder_blocks_1 (rtx, tree, varray_type *);
265 static void reorder_fix_fragments (tree);
266 static tree blocks_nreverse (tree);
267 static int all_blocks (tree, tree *);
268 static tree *get_block_vector (tree, int *);
269 extern tree debug_find_var_in_block_tree (tree, tree);
270 /* We always define `record_insns' even if its not used so that we
271 can always export `prologue_epilogue_contains'. */
272 static void record_insns (rtx, varray_type *) ATTRIBUTE_UNUSED;
273 static int contains (rtx, varray_type);
275 static void emit_return_into_block (basic_block, rtx);
277 static void put_addressof_into_stack (rtx, htab_t);
278 static bool purge_addressof_1 (rtx *, rtx, int, int, int, htab_t);
279 static void purge_single_hard_subreg_set (rtx);
280 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
281 static rtx keep_stack_depressed (rtx);
283 static int is_addressof (rtx *, void *);
284 static hashval_t insns_for_mem_hash (const void *);
285 static int insns_for_mem_comp (const void *, const void *);
286 static int insns_for_mem_walk (rtx *, void *);
287 static void compute_insns_for_mem (rtx, rtx, htab_t);
288 static void prepare_function_start (tree);
289 static void do_clobber_return_reg (rtx, void *);
290 static void do_use_return_reg (rtx, void *);
291 static void instantiate_virtual_regs_lossage (rtx);
292 static tree split_complex_args (tree);
293 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
295 /* Pointer to chain of `struct function' for containing functions. */
296 static GTY(()) struct function *outer_function_chain;
298 /* List of insns that were postponed by purge_addressof_1. */
299 static rtx postponed_insns;
301 /* Given a function decl for a containing function,
302 return the `struct function' for it. */
305 find_function_data (tree decl)
309 for (p = outer_function_chain; p; p = p->outer)
316 /* Save the current context for compilation of a nested function.
317 This is called from language-specific code. The caller should use
318 the enter_nested langhook to save any language-specific state,
319 since this function knows only about language-independent
323 push_function_context_to (tree context)
329 if (context == current_function_decl)
330 cfun->contains_functions = 1;
333 struct function *containing = find_function_data (context);
334 containing->contains_functions = 1;
339 init_dummy_function_start ();
342 p->outer = outer_function_chain;
343 outer_function_chain = p;
344 p->fixup_var_refs_queue = 0;
346 (*lang_hooks.function.enter_nested) (p);
352 push_function_context (void)
354 push_function_context_to (current_function_decl);
357 /* Restore the last saved context, at the end of a nested function.
358 This function is called from language-specific code. */
361 pop_function_context_from (tree context ATTRIBUTE_UNUSED)
363 struct function *p = outer_function_chain;
364 struct var_refs_queue *queue;
367 outer_function_chain = p->outer;
369 current_function_decl = p->decl;
372 restore_emit_status (p);
374 (*lang_hooks.function.leave_nested) (p);
376 /* Finish doing put_var_into_stack for any of our variables which became
377 addressable during the nested function. If only one entry has to be
378 fixed up, just do that one. Otherwise, first make a list of MEMs that
379 are not to be unshared. */
380 if (p->fixup_var_refs_queue == 0)
382 else if (p->fixup_var_refs_queue->next == 0)
383 fixup_var_refs (p->fixup_var_refs_queue->modified,
384 p->fixup_var_refs_queue->promoted_mode,
385 p->fixup_var_refs_queue->unsignedp,
386 p->fixup_var_refs_queue->modified, 0);
391 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
392 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
394 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
395 fixup_var_refs (queue->modified, queue->promoted_mode,
396 queue->unsignedp, list, 0);
400 p->fixup_var_refs_queue = 0;
402 /* Reset variables that have known state during rtx generation. */
403 rtx_equal_function_value_matters = 1;
404 virtuals_instantiated = 0;
405 generating_concat_p = 1;
409 pop_function_context (void)
411 pop_function_context_from (current_function_decl);
414 /* Clear out all parts of the state in F that can safely be discarded
415 after the function has been parsed, but not compiled, to let
416 garbage collection reclaim the memory. */
419 free_after_parsing (struct function *f)
421 /* f->expr->forced_labels is used by code generation. */
422 /* f->emit->regno_reg_rtx is used by code generation. */
423 /* f->varasm is used by code generation. */
424 /* f->eh->eh_return_stub_label is used by code generation. */
426 (*lang_hooks.function.final) (f);
430 /* Clear out all parts of the state in F that can safely be discarded
431 after the function has been compiled, to let garbage collection
432 reclaim the memory. */
435 free_after_compilation (struct function *f)
443 f->x_temp_slots = NULL;
444 f->arg_offset_rtx = NULL;
445 f->return_rtx = NULL;
446 f->internal_arg_pointer = NULL;
447 f->x_nonlocal_labels = NULL;
448 f->x_nonlocal_goto_handler_slots = NULL;
449 f->x_nonlocal_goto_handler_labels = NULL;
450 f->x_nonlocal_goto_stack_level = NULL;
451 f->x_cleanup_label = NULL;
452 f->x_return_label = NULL;
453 f->computed_goto_common_label = NULL;
454 f->computed_goto_common_reg = NULL;
455 f->x_save_expr_regs = NULL;
456 f->x_stack_slot_list = NULL;
457 f->x_rtl_expr_chain = NULL;
458 f->x_tail_recursion_label = NULL;
459 f->x_tail_recursion_reentry = NULL;
460 f->x_arg_pointer_save_area = NULL;
461 f->x_clobber_return_insn = NULL;
462 f->x_context_display = NULL;
463 f->x_trampoline_list = NULL;
464 f->x_parm_birth_insn = NULL;
465 f->x_last_parm_insn = NULL;
466 f->x_parm_reg_stack_loc = NULL;
467 f->fixup_var_refs_queue = NULL;
468 f->original_arg_vector = NULL;
469 f->original_decl_initial = NULL;
470 f->inl_last_parm_insn = NULL;
471 f->epilogue_delay_list = NULL;
474 /* Allocate fixed slots in the stack frame of the current function. */
476 /* Return size needed for stack frame based on slots so far allocated in
478 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
479 the caller may have to do that. */
482 get_func_frame_size (struct function *f)
484 #ifdef FRAME_GROWS_DOWNWARD
485 return -f->x_frame_offset;
487 return f->x_frame_offset;
491 /* Return size needed for stack frame based on slots so far allocated.
492 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
493 the caller may have to do that. */
495 get_frame_size (void)
497 return get_func_frame_size (cfun);
500 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
501 with machine mode MODE.
503 ALIGN controls the amount of alignment for the address of the slot:
504 0 means according to MODE,
505 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
506 positive specifies alignment boundary in bits.
508 We do not round to stack_boundary here.
510 FUNCTION specifies the function to allocate in. */
513 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
514 struct function *function)
517 int bigend_correction = 0;
519 int frame_off, frame_alignment, frame_phase;
526 alignment = BIGGEST_ALIGNMENT;
528 alignment = GET_MODE_ALIGNMENT (mode);
530 /* Allow the target to (possibly) increase the alignment of this
532 type = (*lang_hooks.types.type_for_mode) (mode, 0);
534 alignment = LOCAL_ALIGNMENT (type, alignment);
536 alignment /= BITS_PER_UNIT;
538 else if (align == -1)
540 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
541 size = CEIL_ROUND (size, alignment);
544 alignment = align / BITS_PER_UNIT;
546 #ifdef FRAME_GROWS_DOWNWARD
547 function->x_frame_offset -= size;
550 /* Ignore alignment we can't do with expected alignment of the boundary. */
551 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
552 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
554 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
555 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
557 /* Calculate how many bytes the start of local variables is off from
559 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
560 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
561 frame_phase = frame_off ? frame_alignment - frame_off : 0;
563 /* Round the frame offset to the specified alignment. The default is
564 to always honor requests to align the stack but a port may choose to
565 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
566 if (STACK_ALIGNMENT_NEEDED
570 /* We must be careful here, since FRAME_OFFSET might be negative and
571 division with a negative dividend isn't as well defined as we might
572 like. So we instead assume that ALIGNMENT is a power of two and
573 use logical operations which are unambiguous. */
574 #ifdef FRAME_GROWS_DOWNWARD
575 function->x_frame_offset
576 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
579 function->x_frame_offset
580 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
585 /* On a big-endian machine, if we are allocating more space than we will use,
586 use the least significant bytes of those that are allocated. */
587 if (BYTES_BIG_ENDIAN && mode != BLKmode)
588 bigend_correction = size - GET_MODE_SIZE (mode);
590 /* If we have already instantiated virtual registers, return the actual
591 address relative to the frame pointer. */
592 if (function == cfun && virtuals_instantiated)
593 addr = plus_constant (frame_pointer_rtx,
595 (frame_offset + bigend_correction
596 + STARTING_FRAME_OFFSET, Pmode));
598 addr = plus_constant (virtual_stack_vars_rtx,
600 (function->x_frame_offset + bigend_correction,
603 #ifndef FRAME_GROWS_DOWNWARD
604 function->x_frame_offset += size;
607 x = gen_rtx_MEM (mode, addr);
609 function->x_stack_slot_list
610 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
615 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
619 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
621 return assign_stack_local_1 (mode, size, align, cfun);
624 /* Allocate a temporary stack slot and record it for possible later
627 MODE is the machine mode to be given to the returned rtx.
629 SIZE is the size in units of the space required. We do no rounding here
630 since assign_stack_local will do any required rounding.
632 KEEP is 1 if this slot is to be retained after a call to
633 free_temp_slots. Automatic variables for a block are allocated
634 with this flag. KEEP is 2 if we allocate a longer term temporary,
635 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
636 if we are to allocate something at an inner level to be treated as
637 a variable in the block (e.g., a SAVE_EXPR).
639 TYPE is the type that will be used for the stack slot. */
642 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, int keep,
646 struct temp_slot *p, *best_p = 0;
649 /* If SIZE is -1 it means that somebody tried to allocate a temporary
650 of a variable size. */
655 align = BIGGEST_ALIGNMENT;
657 align = GET_MODE_ALIGNMENT (mode);
660 type = (*lang_hooks.types.type_for_mode) (mode, 0);
663 align = LOCAL_ALIGNMENT (type, align);
665 /* Try to find an available, already-allocated temporary of the proper
666 mode which meets the size and alignment requirements. Choose the
667 smallest one with the closest alignment. */
668 for (p = temp_slots; p; p = p->next)
669 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
671 && objects_must_conflict_p (p->type, type)
672 && (best_p == 0 || best_p->size > p->size
673 || (best_p->size == p->size && best_p->align > p->align)))
675 if (p->align == align && p->size == size)
683 /* Make our best, if any, the one to use. */
686 /* If there are enough aligned bytes left over, make them into a new
687 temp_slot so that the extra bytes don't get wasted. Do this only
688 for BLKmode slots, so that we can be sure of the alignment. */
689 if (GET_MODE (best_p->slot) == BLKmode)
691 int alignment = best_p->align / BITS_PER_UNIT;
692 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
694 if (best_p->size - rounded_size >= alignment)
696 p = ggc_alloc (sizeof (struct temp_slot));
697 p->in_use = p->addr_taken = 0;
698 p->size = best_p->size - rounded_size;
699 p->base_offset = best_p->base_offset + rounded_size;
700 p->full_size = best_p->full_size - rounded_size;
701 p->slot = gen_rtx_MEM (BLKmode,
702 plus_constant (XEXP (best_p->slot, 0),
704 p->align = best_p->align;
707 p->type = best_p->type;
708 p->next = temp_slots;
711 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
714 best_p->size = rounded_size;
715 best_p->full_size = rounded_size;
722 /* If we still didn't find one, make a new temporary. */
725 HOST_WIDE_INT frame_offset_old = frame_offset;
727 p = ggc_alloc (sizeof (struct temp_slot));
729 /* We are passing an explicit alignment request to assign_stack_local.
730 One side effect of that is assign_stack_local will not round SIZE
731 to ensure the frame offset remains suitably aligned.
733 So for requests which depended on the rounding of SIZE, we go ahead
734 and round it now. We also make sure ALIGNMENT is at least
735 BIGGEST_ALIGNMENT. */
736 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
738 p->slot = assign_stack_local (mode,
740 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
746 /* The following slot size computation is necessary because we don't
747 know the actual size of the temporary slot until assign_stack_local
748 has performed all the frame alignment and size rounding for the
749 requested temporary. Note that extra space added for alignment
750 can be either above or below this stack slot depending on which
751 way the frame grows. We include the extra space if and only if it
752 is above this slot. */
753 #ifdef FRAME_GROWS_DOWNWARD
754 p->size = frame_offset_old - frame_offset;
759 /* Now define the fields used by combine_temp_slots. */
760 #ifdef FRAME_GROWS_DOWNWARD
761 p->base_offset = frame_offset;
762 p->full_size = frame_offset_old - frame_offset;
764 p->base_offset = frame_offset_old;
765 p->full_size = frame_offset - frame_offset_old;
768 p->next = temp_slots;
774 p->rtl_expr = seq_rtl_expr;
779 p->level = target_temp_slot_level;
784 p->level = var_temp_slot_level;
789 p->level = temp_slot_level;
794 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
795 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
796 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
798 /* If we know the alias set for the memory that will be used, use
799 it. If there's no TYPE, then we don't know anything about the
800 alias set for the memory. */
801 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
802 set_mem_align (slot, align);
804 /* If a type is specified, set the relevant flags. */
807 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
808 && TYPE_READONLY (type));
809 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
810 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
816 /* Allocate a temporary stack slot and record it for possible later
817 reuse. First three arguments are same as in preceding function. */
820 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
822 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
825 /* Assign a temporary.
826 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
827 and so that should be used in error messages. In either case, we
828 allocate of the given type.
829 KEEP is as for assign_stack_temp.
830 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
831 it is 0 if a register is OK.
832 DONT_PROMOTE is 1 if we should not promote values in register
836 assign_temp (tree type_or_decl, int keep, int memory_required,
837 int dont_promote ATTRIBUTE_UNUSED)
840 enum machine_mode mode;
841 #ifndef PROMOTE_FOR_CALL_ONLY
845 if (DECL_P (type_or_decl))
846 decl = type_or_decl, type = TREE_TYPE (decl);
848 decl = NULL, type = type_or_decl;
850 mode = TYPE_MODE (type);
851 #ifndef PROMOTE_FOR_CALL_ONLY
852 unsignedp = TREE_UNSIGNED (type);
855 if (mode == BLKmode || memory_required)
857 HOST_WIDE_INT size = int_size_in_bytes (type);
860 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
861 problems with allocating the stack space. */
865 /* Unfortunately, we don't yet know how to allocate variable-sized
866 temporaries. However, sometimes we have a fixed upper limit on
867 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
868 instead. This is the case for Chill variable-sized strings. */
869 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
870 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
871 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
872 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
874 /* The size of the temporary may be too large to fit into an integer. */
875 /* ??? Not sure this should happen except for user silliness, so limit
876 this to things that aren't compiler-generated temporaries. The
877 rest of the time we'll abort in assign_stack_temp_for_type. */
878 if (decl && size == -1
879 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
881 error ("%Hsize of variable '%D' is too large",
882 &DECL_SOURCE_LOCATION (decl), decl);
886 tmp = assign_stack_temp_for_type (mode, size, keep, type);
890 #ifndef PROMOTE_FOR_CALL_ONLY
892 mode = promote_mode (type, mode, &unsignedp, 0);
895 return gen_reg_rtx (mode);
898 /* Combine temporary stack slots which are adjacent on the stack.
900 This allows for better use of already allocated stack space. This is only
901 done for BLKmode slots because we can be sure that we won't have alignment
902 problems in this case. */
905 combine_temp_slots (void)
907 struct temp_slot *p, *q;
908 struct temp_slot *prev_p, *prev_q;
911 /* We can't combine slots, because the information about which slot
912 is in which alias set will be lost. */
913 if (flag_strict_aliasing)
916 /* If there are a lot of temp slots, don't do anything unless
917 high levels of optimization. */
918 if (! flag_expensive_optimizations)
919 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
920 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
923 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
927 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
928 for (q = p->next, prev_q = p; q; q = prev_q->next)
931 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
933 if (p->base_offset + p->full_size == q->base_offset)
935 /* Q comes after P; combine Q into P. */
937 p->full_size += q->full_size;
940 else if (q->base_offset + q->full_size == p->base_offset)
942 /* P comes after Q; combine P into Q. */
944 q->full_size += p->full_size;
949 /* Either delete Q or advance past it. */
951 prev_q->next = q->next;
955 /* Either delete P or advance past it. */
959 prev_p->next = p->next;
961 temp_slots = p->next;
968 /* Find the temp slot corresponding to the object at address X. */
970 static struct temp_slot *
971 find_temp_slot_from_address (rtx x)
976 for (p = temp_slots; p; p = p->next)
981 else if (XEXP (p->slot, 0) == x
983 || (GET_CODE (x) == PLUS
984 && XEXP (x, 0) == virtual_stack_vars_rtx
985 && GET_CODE (XEXP (x, 1)) == CONST_INT
986 && INTVAL (XEXP (x, 1)) >= p->base_offset
987 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
990 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
991 for (next = p->address; next; next = XEXP (next, 1))
992 if (XEXP (next, 0) == x)
996 /* If we have a sum involving a register, see if it points to a temp
998 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
999 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1001 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1002 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1008 /* Indicate that NEW is an alternate way of referring to the temp slot
1009 that previously was known by OLD. */
1012 update_temp_slot_address (rtx old, rtx new)
1014 struct temp_slot *p;
1016 if (rtx_equal_p (old, new))
1019 p = find_temp_slot_from_address (old);
1021 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1022 is a register, see if one operand of the PLUS is a temporary
1023 location. If so, NEW points into it. Otherwise, if both OLD and
1024 NEW are a PLUS and if there is a register in common between them.
1025 If so, try a recursive call on those values. */
1028 if (GET_CODE (old) != PLUS)
1031 if (GET_CODE (new) == REG)
1033 update_temp_slot_address (XEXP (old, 0), new);
1034 update_temp_slot_address (XEXP (old, 1), new);
1037 else if (GET_CODE (new) != PLUS)
1040 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1041 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1042 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1043 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1044 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1045 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1046 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1047 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1052 /* Otherwise add an alias for the temp's address. */
1053 else if (p->address == 0)
1057 if (GET_CODE (p->address) != EXPR_LIST)
1058 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1060 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1064 /* If X could be a reference to a temporary slot, mark the fact that its
1065 address was taken. */
1068 mark_temp_addr_taken (rtx x)
1070 struct temp_slot *p;
1075 /* If X is not in memory or is at a constant address, it cannot be in
1076 a temporary slot. */
1077 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1080 p = find_temp_slot_from_address (XEXP (x, 0));
1085 /* If X could be a reference to a temporary slot, mark that slot as
1086 belonging to the to one level higher than the current level. If X
1087 matched one of our slots, just mark that one. Otherwise, we can't
1088 easily predict which it is, so upgrade all of them. Kept slots
1089 need not be touched.
1091 This is called when an ({...}) construct occurs and a statement
1092 returns a value in memory. */
1095 preserve_temp_slots (rtx x)
1097 struct temp_slot *p = 0;
1099 /* If there is no result, we still might have some objects whose address
1100 were taken, so we need to make sure they stay around. */
1103 for (p = temp_slots; p; p = p->next)
1104 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1110 /* If X is a register that is being used as a pointer, see if we have
1111 a temporary slot we know it points to. To be consistent with
1112 the code below, we really should preserve all non-kept slots
1113 if we can't find a match, but that seems to be much too costly. */
1114 if (GET_CODE (x) == REG && REG_POINTER (x))
1115 p = find_temp_slot_from_address (x);
1117 /* If X is not in memory or is at a constant address, it cannot be in
1118 a temporary slot, but it can contain something whose address was
1120 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1122 for (p = temp_slots; p; p = p->next)
1123 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1129 /* First see if we can find a match. */
1131 p = find_temp_slot_from_address (XEXP (x, 0));
1135 /* Move everything at our level whose address was taken to our new
1136 level in case we used its address. */
1137 struct temp_slot *q;
1139 if (p->level == temp_slot_level)
1141 for (q = temp_slots; q; q = q->next)
1142 if (q != p && q->addr_taken && q->level == p->level)
1151 /* Otherwise, preserve all non-kept slots at this level. */
1152 for (p = temp_slots; p; p = p->next)
1153 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1157 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1158 with that RTL_EXPR, promote it into a temporary slot at the present
1159 level so it will not be freed when we free slots made in the
1163 preserve_rtl_expr_result (rtx x)
1165 struct temp_slot *p;
1167 /* If X is not in memory or is at a constant address, it cannot be in
1168 a temporary slot. */
1169 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1172 /* If we can find a match, move it to our level unless it is already at
1174 p = find_temp_slot_from_address (XEXP (x, 0));
1177 p->level = MIN (p->level, temp_slot_level);
1184 /* Free all temporaries used so far. This is normally called at the end
1185 of generating code for a statement. Don't free any temporaries
1186 currently in use for an RTL_EXPR that hasn't yet been emitted.
1187 We could eventually do better than this since it can be reused while
1188 generating the same RTL_EXPR, but this is complex and probably not
1192 free_temp_slots (void)
1194 struct temp_slot *p;
1196 for (p = temp_slots; p; p = p->next)
1197 if (p->in_use && p->level == temp_slot_level && ! p->keep
1198 && p->rtl_expr == 0)
1201 combine_temp_slots ();
1204 /* Free all temporary slots used in T, an RTL_EXPR node. */
1207 free_temps_for_rtl_expr (tree t)
1209 struct temp_slot *p;
1211 for (p = temp_slots; p; p = p->next)
1212 if (p->rtl_expr == t)
1214 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1215 needs to be preserved. This can happen if a temporary in
1216 the RTL_EXPR was addressed; preserve_temp_slots will move
1217 the temporary into a higher level. */
1218 if (temp_slot_level <= p->level)
1221 p->rtl_expr = NULL_TREE;
1224 combine_temp_slots ();
1227 /* Mark all temporaries ever allocated in this function as not suitable
1228 for reuse until the current level is exited. */
1231 mark_all_temps_used (void)
1233 struct temp_slot *p;
1235 for (p = temp_slots; p; p = p->next)
1237 p->in_use = p->keep = 1;
1238 p->level = MIN (p->level, temp_slot_level);
1242 /* Push deeper into the nesting level for stack temporaries. */
1245 push_temp_slots (void)
1250 /* Pop a temporary nesting level. All slots in use in the current level
1254 pop_temp_slots (void)
1256 struct temp_slot *p;
1258 for (p = temp_slots; p; p = p->next)
1259 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1262 combine_temp_slots ();
1267 /* Initialize temporary slots. */
1270 init_temp_slots (void)
1272 /* We have not allocated any temporaries yet. */
1274 temp_slot_level = 0;
1275 var_temp_slot_level = 0;
1276 target_temp_slot_level = 0;
1279 /* Retroactively move an auto variable from a register to a stack
1280 slot. This is done when an address-reference to the variable is
1281 seen. If RESCAN is true, all previously emitted instructions are
1282 examined and modified to handle the fact that DECL is now
1286 put_var_into_stack (tree decl, int rescan)
1289 enum machine_mode promoted_mode, decl_mode;
1290 struct function *function = 0;
1292 int can_use_addressof;
1293 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1294 int usedp = (TREE_USED (decl)
1295 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1297 context = decl_function_context (decl);
1299 /* Get the current rtl used for this object and its original mode. */
1300 reg = (TREE_CODE (decl) == SAVE_EXPR
1301 ? SAVE_EXPR_RTL (decl)
1302 : DECL_RTL_IF_SET (decl));
1304 /* No need to do anything if decl has no rtx yet
1305 since in that case caller is setting TREE_ADDRESSABLE
1306 and a stack slot will be assigned when the rtl is made. */
1310 /* Get the declared mode for this object. */
1311 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1312 : DECL_MODE (decl));
1313 /* Get the mode it's actually stored in. */
1314 promoted_mode = GET_MODE (reg);
1316 /* If this variable comes from an outer function, find that
1317 function's saved context. Don't use find_function_data here,
1318 because it might not be in any active function.
1319 FIXME: Is that really supposed to happen?
1320 It does in ObjC at least. */
1321 if (context != current_function_decl && context != inline_function_decl)
1322 for (function = outer_function_chain; function; function = function->outer)
1323 if (function->decl == context)
1326 /* If this is a variable-size object with a pseudo to address it,
1327 put that pseudo into the stack, if the var is nonlocal. */
1328 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1329 && GET_CODE (reg) == MEM
1330 && GET_CODE (XEXP (reg, 0)) == REG
1331 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1333 reg = XEXP (reg, 0);
1334 decl_mode = promoted_mode = GET_MODE (reg);
1340 /* FIXME make it work for promoted modes too */
1341 && decl_mode == promoted_mode
1342 #ifdef NON_SAVING_SETJMP
1343 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1347 /* If we can't use ADDRESSOF, make sure we see through one we already
1349 if (! can_use_addressof && GET_CODE (reg) == MEM
1350 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1351 reg = XEXP (XEXP (reg, 0), 0);
1353 /* Now we should have a value that resides in one or more pseudo regs. */
1355 if (GET_CODE (reg) == REG)
1357 /* If this variable lives in the current function and we don't need
1358 to put things in the stack for the sake of setjmp, try to keep it
1359 in a register until we know we actually need the address. */
1360 if (can_use_addressof)
1361 gen_mem_addressof (reg, decl, rescan);
1363 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1364 decl_mode, volatilep, 0, usedp, 0);
1366 else if (GET_CODE (reg) == CONCAT)
1368 /* A CONCAT contains two pseudos; put them both in the stack.
1369 We do it so they end up consecutive.
1370 We fixup references to the parts only after we fixup references
1371 to the whole CONCAT, lest we do double fixups for the latter
1373 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1374 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1375 rtx lopart = XEXP (reg, 0);
1376 rtx hipart = XEXP (reg, 1);
1377 #ifdef FRAME_GROWS_DOWNWARD
1378 /* Since part 0 should have a lower address, do it second. */
1379 put_reg_into_stack (function, hipart, part_type, part_mode,
1380 part_mode, volatilep, 0, 0, 0);
1381 put_reg_into_stack (function, lopart, part_type, part_mode,
1382 part_mode, volatilep, 0, 0, 0);
1384 put_reg_into_stack (function, lopart, part_type, part_mode,
1385 part_mode, volatilep, 0, 0, 0);
1386 put_reg_into_stack (function, hipart, part_type, part_mode,
1387 part_mode, volatilep, 0, 0, 0);
1390 /* Change the CONCAT into a combined MEM for both parts. */
1391 PUT_CODE (reg, MEM);
1392 MEM_ATTRS (reg) = 0;
1394 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1395 already computed alias sets. Here we want to re-generate. */
1397 SET_DECL_RTL (decl, NULL);
1398 set_mem_attributes (reg, decl, 1);
1400 SET_DECL_RTL (decl, reg);
1402 /* The two parts are in memory order already.
1403 Use the lower parts address as ours. */
1404 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1405 /* Prevent sharing of rtl that might lose. */
1406 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1407 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1408 if (usedp && rescan)
1410 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1412 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1413 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1420 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1421 into the stack frame of FUNCTION (0 means the current function).
1422 DECL_MODE is the machine mode of the user-level data type.
1423 PROMOTED_MODE is the machine mode of the register.
1424 VOLATILE_P is nonzero if this is for a "volatile" decl.
1425 USED_P is nonzero if this reg might have already been used in an insn. */
1428 put_reg_into_stack (struct function *function, rtx reg, tree type,
1429 enum machine_mode promoted_mode, enum machine_mode decl_mode,
1430 int volatile_p, unsigned int original_regno, int used_p, htab_t ht)
1432 struct function *func = function ? function : cfun;
1434 unsigned int regno = original_regno;
1437 regno = REGNO (reg);
1439 if (regno < func->x_max_parm_reg)
1440 new = func->x_parm_reg_stack_loc[regno];
1443 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1445 PUT_CODE (reg, MEM);
1446 PUT_MODE (reg, decl_mode);
1447 XEXP (reg, 0) = XEXP (new, 0);
1448 MEM_ATTRS (reg) = 0;
1449 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1450 MEM_VOLATILE_P (reg) = volatile_p;
1452 /* If this is a memory ref that contains aggregate components,
1453 mark it as such for cse and loop optimize. If we are reusing a
1454 previously generated stack slot, then we need to copy the bit in
1455 case it was set for other reasons. For instance, it is set for
1456 __builtin_va_alist. */
1459 MEM_SET_IN_STRUCT_P (reg,
1460 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1461 set_mem_alias_set (reg, get_alias_set (type));
1465 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1468 /* Make sure that all refs to the variable, previously made
1469 when it was a register, are fixed up to be valid again.
1470 See function above for meaning of arguments. */
1473 schedule_fixup_var_refs (struct function *function, rtx reg, tree type,
1474 enum machine_mode promoted_mode, htab_t ht)
1476 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1480 struct var_refs_queue *temp;
1482 temp = ggc_alloc (sizeof (struct var_refs_queue));
1483 temp->modified = reg;
1484 temp->promoted_mode = promoted_mode;
1485 temp->unsignedp = unsigned_p;
1486 temp->next = function->fixup_var_refs_queue;
1487 function->fixup_var_refs_queue = temp;
1490 /* Variable is local; fix it up now. */
1491 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1495 fixup_var_refs (rtx var, enum machine_mode promoted_mode, int unsignedp,
1496 rtx may_share, htab_t ht)
1499 rtx first_insn = get_insns ();
1500 struct sequence_stack *stack = seq_stack;
1501 tree rtl_exps = rtl_expr_chain;
1503 /* If there's a hash table, it must record all uses of VAR. */
1508 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1513 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1514 stack == 0, may_share);
1516 /* Scan all pending sequences too. */
1517 for (; stack; stack = stack->next)
1519 push_to_full_sequence (stack->first, stack->last);
1520 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1521 stack->next != 0, may_share);
1522 /* Update remembered end of sequence
1523 in case we added an insn at the end. */
1524 stack->last = get_last_insn ();
1528 /* Scan all waiting RTL_EXPRs too. */
1529 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1531 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1532 if (seq != const0_rtx && seq != 0)
1534 push_to_sequence (seq);
1535 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1542 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1543 some part of an insn. Return a struct fixup_replacement whose OLD
1544 value is equal to X. Allocate a new structure if no such entry exists. */
1546 static struct fixup_replacement *
1547 find_fixup_replacement (struct fixup_replacement **replacements, rtx x)
1549 struct fixup_replacement *p;
1551 /* See if we have already replaced this. */
1552 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1557 p = xmalloc (sizeof (struct fixup_replacement));
1560 p->next = *replacements;
1567 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1568 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1569 for the current function. MAY_SHARE is either a MEM that is not
1570 to be unshared or a list of them. */
1573 fixup_var_refs_insns (rtx insn, rtx var, enum machine_mode promoted_mode,
1574 int unsignedp, int toplevel, rtx may_share)
1578 /* fixup_var_refs_insn might modify insn, so save its next
1580 rtx next = NEXT_INSN (insn);
1582 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1583 the three sequences they (potentially) contain, and process
1584 them recursively. The CALL_INSN itself is not interesting. */
1586 if (GET_CODE (insn) == CALL_INSN
1587 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1591 /* Look at the Normal call, sibling call and tail recursion
1592 sequences attached to the CALL_PLACEHOLDER. */
1593 for (i = 0; i < 3; i++)
1595 rtx seq = XEXP (PATTERN (insn), i);
1598 push_to_sequence (seq);
1599 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1601 XEXP (PATTERN (insn), i) = get_insns ();
1607 else if (INSN_P (insn))
1608 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1615 /* Look up the insns which reference VAR in HT and fix them up. Other
1616 arguments are the same as fixup_var_refs_insns.
1618 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1619 because the hash table will point straight to the interesting insn
1620 (inside the CALL_PLACEHOLDER). */
1623 fixup_var_refs_insns_with_hash (htab_t ht, rtx var, enum machine_mode promoted_mode,
1624 int unsignedp, rtx may_share)
1626 struct insns_for_mem_entry tmp;
1627 struct insns_for_mem_entry *ime;
1631 ime = htab_find (ht, &tmp);
1632 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1633 if (INSN_P (XEXP (insn_list, 0)))
1634 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1635 unsignedp, 1, may_share);
1639 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1640 the insn under examination, VAR is the variable to fix up
1641 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1642 TOPLEVEL is nonzero if this is the main insn chain for this
1646 fixup_var_refs_insn (rtx insn, rtx var, enum machine_mode promoted_mode,
1647 int unsignedp, int toplevel, rtx no_share)
1650 rtx set, prev, prev_set;
1653 /* Remember the notes in case we delete the insn. */
1654 note = REG_NOTES (insn);
1656 /* If this is a CLOBBER of VAR, delete it.
1658 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1659 and REG_RETVAL notes too. */
1660 if (GET_CODE (PATTERN (insn)) == CLOBBER
1661 && (XEXP (PATTERN (insn), 0) == var
1662 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1663 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1664 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1666 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1667 /* The REG_LIBCALL note will go away since we are going to
1668 turn INSN into a NOTE, so just delete the
1669 corresponding REG_RETVAL note. */
1670 remove_note (XEXP (note, 0),
1671 find_reg_note (XEXP (note, 0), REG_RETVAL,
1677 /* The insn to load VAR from a home in the arglist
1678 is now a no-op. When we see it, just delete it.
1679 Similarly if this is storing VAR from a register from which
1680 it was loaded in the previous insn. This will occur
1681 when an ADDRESSOF was made for an arglist slot. */
1683 && (set = single_set (insn)) != 0
1684 && SET_DEST (set) == var
1685 /* If this represents the result of an insn group,
1686 don't delete the insn. */
1687 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1688 && (rtx_equal_p (SET_SRC (set), var)
1689 || (GET_CODE (SET_SRC (set)) == REG
1690 && (prev = prev_nonnote_insn (insn)) != 0
1691 && (prev_set = single_set (prev)) != 0
1692 && SET_DEST (prev_set) == SET_SRC (set)
1693 && rtx_equal_p (SET_SRC (prev_set), var))))
1699 struct fixup_replacement *replacements = 0;
1700 rtx next_insn = NEXT_INSN (insn);
1702 if (SMALL_REGISTER_CLASSES)
1704 /* If the insn that copies the results of a CALL_INSN
1705 into a pseudo now references VAR, we have to use an
1706 intermediate pseudo since we want the life of the
1707 return value register to be only a single insn.
1709 If we don't use an intermediate pseudo, such things as
1710 address computations to make the address of VAR valid
1711 if it is not can be placed between the CALL_INSN and INSN.
1713 To make sure this doesn't happen, we record the destination
1714 of the CALL_INSN and see if the next insn uses both that
1717 if (call_dest != 0 && GET_CODE (insn) == INSN
1718 && reg_mentioned_p (var, PATTERN (insn))
1719 && reg_mentioned_p (call_dest, PATTERN (insn)))
1721 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1723 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1725 PATTERN (insn) = replace_rtx (PATTERN (insn),
1729 if (GET_CODE (insn) == CALL_INSN
1730 && GET_CODE (PATTERN (insn)) == SET)
1731 call_dest = SET_DEST (PATTERN (insn));
1732 else if (GET_CODE (insn) == CALL_INSN
1733 && GET_CODE (PATTERN (insn)) == PARALLEL
1734 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1735 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1740 /* See if we have to do anything to INSN now that VAR is in
1741 memory. If it needs to be loaded into a pseudo, use a single
1742 pseudo for the entire insn in case there is a MATCH_DUP
1743 between two operands. We pass a pointer to the head of
1744 a list of struct fixup_replacements. If fixup_var_refs_1
1745 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1746 it will record them in this list.
1748 If it allocated a pseudo for any replacement, we copy into
1751 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1752 &replacements, no_share);
1754 /* If this is last_parm_insn, and any instructions were output
1755 after it to fix it up, then we must set last_parm_insn to
1756 the last such instruction emitted. */
1757 if (insn == last_parm_insn)
1758 last_parm_insn = PREV_INSN (next_insn);
1760 while (replacements)
1762 struct fixup_replacement *next;
1764 if (GET_CODE (replacements->new) == REG)
1769 /* OLD might be a (subreg (mem)). */
1770 if (GET_CODE (replacements->old) == SUBREG)
1772 = fixup_memory_subreg (replacements->old, insn,
1776 = fixup_stack_1 (replacements->old, insn);
1778 insert_before = insn;
1780 /* If we are changing the mode, do a conversion.
1781 This might be wasteful, but combine.c will
1782 eliminate much of the waste. */
1784 if (GET_MODE (replacements->new)
1785 != GET_MODE (replacements->old))
1788 convert_move (replacements->new,
1789 replacements->old, unsignedp);
1794 seq = gen_move_insn (replacements->new,
1797 emit_insn_before (seq, insert_before);
1800 next = replacements->next;
1801 free (replacements);
1802 replacements = next;
1806 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1807 But don't touch other insns referred to by reg-notes;
1808 we will get them elsewhere. */
1811 if (GET_CODE (note) != INSN_LIST)
1813 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1815 note = XEXP (note, 1);
1819 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1820 See if the rtx expression at *LOC in INSN needs to be changed.
1822 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1823 contain a list of original rtx's and replacements. If we find that we need
1824 to modify this insn by replacing a memory reference with a pseudo or by
1825 making a new MEM to implement a SUBREG, we consult that list to see if
1826 we have already chosen a replacement. If none has already been allocated,
1827 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1828 or the SUBREG, as appropriate, to the pseudo. */
1831 fixup_var_refs_1 (rtx var, enum machine_mode promoted_mode, rtx *loc, rtx insn,
1832 struct fixup_replacement **replacements, rtx no_share)
1836 RTX_CODE code = GET_CODE (x);
1839 struct fixup_replacement *replacement;
1844 if (XEXP (x, 0) == var)
1846 /* Prevent sharing of rtl that might lose. */
1847 rtx sub = copy_rtx (XEXP (var, 0));
1849 if (! validate_change (insn, loc, sub, 0))
1851 rtx y = gen_reg_rtx (GET_MODE (sub));
1854 /* We should be able to replace with a register or all is lost.
1855 Note that we can't use validate_change to verify this, since
1856 we're not caring for replacing all dups simultaneously. */
1857 if (! validate_replace_rtx (*loc, y, insn))
1860 /* Careful! First try to recognize a direct move of the
1861 value, mimicking how things are done in gen_reload wrt
1862 PLUS. Consider what happens when insn is a conditional
1863 move instruction and addsi3 clobbers flags. */
1866 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1870 if (recog_memoized (new_insn) < 0)
1872 /* That failed. Fall back on force_operand and hope. */
1875 sub = force_operand (sub, y);
1877 emit_insn (gen_move_insn (y, sub));
1883 /* Don't separate setter from user. */
1884 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1885 insn = PREV_INSN (insn);
1888 emit_insn_before (seq, insn);
1896 /* If we already have a replacement, use it. Otherwise,
1897 try to fix up this address in case it is invalid. */
1899 replacement = find_fixup_replacement (replacements, var);
1900 if (replacement->new)
1902 *loc = replacement->new;
1906 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1908 /* Unless we are forcing memory to register or we changed the mode,
1909 we can leave things the way they are if the insn is valid. */
1911 INSN_CODE (insn) = -1;
1912 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1913 && recog_memoized (insn) >= 0)
1916 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1920 /* If X contains VAR, we need to unshare it here so that we update
1921 each occurrence separately. But all identical MEMs in one insn
1922 must be replaced with the same rtx because of the possibility of
1925 if (reg_mentioned_p (var, x))
1927 replacement = find_fixup_replacement (replacements, x);
1928 if (replacement->new == 0)
1929 replacement->new = copy_most_rtx (x, no_share);
1931 *loc = x = replacement->new;
1932 code = GET_CODE (x);
1949 /* Note that in some cases those types of expressions are altered
1950 by optimize_bit_field, and do not survive to get here. */
1951 if (XEXP (x, 0) == var
1952 || (GET_CODE (XEXP (x, 0)) == SUBREG
1953 && SUBREG_REG (XEXP (x, 0)) == var))
1955 /* Get TEM as a valid MEM in the mode presently in the insn.
1957 We don't worry about the possibility of MATCH_DUP here; it
1958 is highly unlikely and would be tricky to handle. */
1961 if (GET_CODE (tem) == SUBREG)
1963 if (GET_MODE_BITSIZE (GET_MODE (tem))
1964 > GET_MODE_BITSIZE (GET_MODE (var)))
1966 replacement = find_fixup_replacement (replacements, var);
1967 if (replacement->new == 0)
1968 replacement->new = gen_reg_rtx (GET_MODE (var));
1969 SUBREG_REG (tem) = replacement->new;
1971 /* The following code works only if we have a MEM, so we
1972 need to handle the subreg here. We directly substitute
1973 it assuming that a subreg must be OK here. We already
1974 scheduled a replacement to copy the mem into the
1980 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
1983 tem = fixup_stack_1 (tem, insn);
1985 /* Unless we want to load from memory, get TEM into the proper mode
1986 for an extract from memory. This can only be done if the
1987 extract is at a constant position and length. */
1989 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1990 && GET_CODE (XEXP (x, 2)) == CONST_INT
1991 && ! mode_dependent_address_p (XEXP (tem, 0))
1992 && ! MEM_VOLATILE_P (tem))
1994 enum machine_mode wanted_mode = VOIDmode;
1995 enum machine_mode is_mode = GET_MODE (tem);
1996 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
1998 if (GET_CODE (x) == ZERO_EXTRACT)
2000 enum machine_mode new_mode
2001 = mode_for_extraction (EP_extzv, 1);
2002 if (new_mode != MAX_MACHINE_MODE)
2003 wanted_mode = new_mode;
2005 else if (GET_CODE (x) == SIGN_EXTRACT)
2007 enum machine_mode new_mode
2008 = mode_for_extraction (EP_extv, 1);
2009 if (new_mode != MAX_MACHINE_MODE)
2010 wanted_mode = new_mode;
2013 /* If we have a narrower mode, we can do something. */
2014 if (wanted_mode != VOIDmode
2015 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2017 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2018 rtx old_pos = XEXP (x, 2);
2021 /* If the bytes and bits are counted differently, we
2022 must adjust the offset. */
2023 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2024 offset = (GET_MODE_SIZE (is_mode)
2025 - GET_MODE_SIZE (wanted_mode) - offset);
2027 pos %= GET_MODE_BITSIZE (wanted_mode);
2029 newmem = adjust_address_nv (tem, wanted_mode, offset);
2031 /* Make the change and see if the insn remains valid. */
2032 INSN_CODE (insn) = -1;
2033 XEXP (x, 0) = newmem;
2034 XEXP (x, 2) = GEN_INT (pos);
2036 if (recog_memoized (insn) >= 0)
2039 /* Otherwise, restore old position. XEXP (x, 0) will be
2041 XEXP (x, 2) = old_pos;
2045 /* If we get here, the bitfield extract insn can't accept a memory
2046 reference. Copy the input into a register. */
2048 tem1 = gen_reg_rtx (GET_MODE (tem));
2049 emit_insn_before (gen_move_insn (tem1, tem), insn);
2056 if (SUBREG_REG (x) == var)
2058 /* If this is a special SUBREG made because VAR was promoted
2059 from a wider mode, replace it with VAR and call ourself
2060 recursively, this time saying that the object previously
2061 had its current mode (by virtue of the SUBREG). */
2063 if (SUBREG_PROMOTED_VAR_P (x))
2066 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2071 /* If this SUBREG makes VAR wider, it has become a paradoxical
2072 SUBREG with VAR in memory, but these aren't allowed at this
2073 stage of the compilation. So load VAR into a pseudo and take
2074 a SUBREG of that pseudo. */
2075 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2077 replacement = find_fixup_replacement (replacements, var);
2078 if (replacement->new == 0)
2079 replacement->new = gen_reg_rtx (promoted_mode);
2080 SUBREG_REG (x) = replacement->new;
2084 /* See if we have already found a replacement for this SUBREG.
2085 If so, use it. Otherwise, make a MEM and see if the insn
2086 is recognized. If not, or if we should force MEM into a register,
2087 make a pseudo for this SUBREG. */
2088 replacement = find_fixup_replacement (replacements, x);
2089 if (replacement->new)
2091 *loc = replacement->new;
2095 replacement->new = *loc = fixup_memory_subreg (x, insn,
2098 INSN_CODE (insn) = -1;
2099 if (! flag_force_mem && recog_memoized (insn) >= 0)
2102 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2108 /* First do special simplification of bit-field references. */
2109 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2110 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2111 optimize_bit_field (x, insn, 0);
2112 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2113 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2114 optimize_bit_field (x, insn, 0);
2116 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2117 into a register and then store it back out. */
2118 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2119 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2120 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2121 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2122 > GET_MODE_SIZE (GET_MODE (var))))
2124 replacement = find_fixup_replacement (replacements, var);
2125 if (replacement->new == 0)
2126 replacement->new = gen_reg_rtx (GET_MODE (var));
2128 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2129 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2132 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2133 insn into a pseudo and store the low part of the pseudo into VAR. */
2134 if (GET_CODE (SET_DEST (x)) == SUBREG
2135 && SUBREG_REG (SET_DEST (x)) == var
2136 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2137 > GET_MODE_SIZE (GET_MODE (var))))
2139 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2140 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2147 rtx dest = SET_DEST (x);
2148 rtx src = SET_SRC (x);
2149 rtx outerdest = dest;
2151 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2152 || GET_CODE (dest) == SIGN_EXTRACT
2153 || GET_CODE (dest) == ZERO_EXTRACT)
2154 dest = XEXP (dest, 0);
2156 if (GET_CODE (src) == SUBREG)
2157 src = SUBREG_REG (src);
2159 /* If VAR does not appear at the top level of the SET
2160 just scan the lower levels of the tree. */
2162 if (src != var && dest != var)
2165 /* We will need to rerecognize this insn. */
2166 INSN_CODE (insn) = -1;
2168 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2169 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2171 /* Since this case will return, ensure we fixup all the
2173 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2174 insn, replacements, no_share);
2175 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2176 insn, replacements, no_share);
2177 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2178 insn, replacements, no_share);
2180 tem = XEXP (outerdest, 0);
2182 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2183 that may appear inside a ZERO_EXTRACT.
2184 This was legitimate when the MEM was a REG. */
2185 if (GET_CODE (tem) == SUBREG
2186 && SUBREG_REG (tem) == var)
2187 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2189 tem = fixup_stack_1 (tem, insn);
2191 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2192 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2193 && ! mode_dependent_address_p (XEXP (tem, 0))
2194 && ! MEM_VOLATILE_P (tem))
2196 enum machine_mode wanted_mode;
2197 enum machine_mode is_mode = GET_MODE (tem);
2198 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2200 wanted_mode = mode_for_extraction (EP_insv, 0);
2202 /* If we have a narrower mode, we can do something. */
2203 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2205 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2206 rtx old_pos = XEXP (outerdest, 2);
2209 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2210 offset = (GET_MODE_SIZE (is_mode)
2211 - GET_MODE_SIZE (wanted_mode) - offset);
2213 pos %= GET_MODE_BITSIZE (wanted_mode);
2215 newmem = adjust_address_nv (tem, wanted_mode, offset);
2217 /* Make the change and see if the insn remains valid. */
2218 INSN_CODE (insn) = -1;
2219 XEXP (outerdest, 0) = newmem;
2220 XEXP (outerdest, 2) = GEN_INT (pos);
2222 if (recog_memoized (insn) >= 0)
2225 /* Otherwise, restore old position. XEXP (x, 0) will be
2227 XEXP (outerdest, 2) = old_pos;
2231 /* If we get here, the bit-field store doesn't allow memory
2232 or isn't located at a constant position. Load the value into
2233 a register, do the store, and put it back into memory. */
2235 tem1 = gen_reg_rtx (GET_MODE (tem));
2236 emit_insn_before (gen_move_insn (tem1, tem), insn);
2237 emit_insn_after (gen_move_insn (tem, tem1), insn);
2238 XEXP (outerdest, 0) = tem1;
2242 /* STRICT_LOW_PART is a no-op on memory references
2243 and it can cause combinations to be unrecognizable,
2246 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2247 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2249 /* A valid insn to copy VAR into or out of a register
2250 must be left alone, to avoid an infinite loop here.
2251 If the reference to VAR is by a subreg, fix that up,
2252 since SUBREG is not valid for a memref.
2253 Also fix up the address of the stack slot.
2255 Note that we must not try to recognize the insn until
2256 after we know that we have valid addresses and no
2257 (subreg (mem ...) ...) constructs, since these interfere
2258 with determining the validity of the insn. */
2260 if ((SET_SRC (x) == var
2261 || (GET_CODE (SET_SRC (x)) == SUBREG
2262 && SUBREG_REG (SET_SRC (x)) == var))
2263 && (GET_CODE (SET_DEST (x)) == REG
2264 || (GET_CODE (SET_DEST (x)) == SUBREG
2265 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2266 && GET_MODE (var) == promoted_mode
2267 && x == single_set (insn))
2271 if (GET_CODE (SET_SRC (x)) == SUBREG
2272 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2273 > GET_MODE_SIZE (GET_MODE (var))))
2275 /* This (subreg VAR) is now a paradoxical subreg. We need
2276 to replace VAR instead of the subreg. */
2277 replacement = find_fixup_replacement (replacements, var);
2278 if (replacement->new == NULL_RTX)
2279 replacement->new = gen_reg_rtx (GET_MODE (var));
2280 SUBREG_REG (SET_SRC (x)) = replacement->new;
2284 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2285 if (replacement->new)
2286 SET_SRC (x) = replacement->new;
2287 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2288 SET_SRC (x) = replacement->new
2289 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2292 SET_SRC (x) = replacement->new
2293 = fixup_stack_1 (SET_SRC (x), insn);
2296 if (recog_memoized (insn) >= 0)
2299 /* INSN is not valid, but we know that we want to
2300 copy SET_SRC (x) to SET_DEST (x) in some way. So
2301 we generate the move and see whether it requires more
2302 than one insn. If it does, we emit those insns and
2303 delete INSN. Otherwise, we can just replace the pattern
2304 of INSN; we have already verified above that INSN has
2305 no other function that to do X. */
2307 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2308 if (NEXT_INSN (pat) != NULL_RTX)
2310 last = emit_insn_before (pat, insn);
2312 /* INSN might have REG_RETVAL or other important notes, so
2313 we need to store the pattern of the last insn in the
2314 sequence into INSN similarly to the normal case. LAST
2315 should not have REG_NOTES, but we allow them if INSN has
2317 if (REG_NOTES (last) && REG_NOTES (insn))
2319 if (REG_NOTES (last))
2320 REG_NOTES (insn) = REG_NOTES (last);
2321 PATTERN (insn) = PATTERN (last);
2326 PATTERN (insn) = PATTERN (pat);
2331 if ((SET_DEST (x) == var
2332 || (GET_CODE (SET_DEST (x)) == SUBREG
2333 && SUBREG_REG (SET_DEST (x)) == var))
2334 && (GET_CODE (SET_SRC (x)) == REG
2335 || (GET_CODE (SET_SRC (x)) == SUBREG
2336 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2337 && GET_MODE (var) == promoted_mode
2338 && x == single_set (insn))
2342 if (GET_CODE (SET_DEST (x)) == SUBREG)
2343 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2346 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2348 if (recog_memoized (insn) >= 0)
2351 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2352 if (NEXT_INSN (pat) != NULL_RTX)
2354 last = emit_insn_before (pat, insn);
2356 /* INSN might have REG_RETVAL or other important notes, so
2357 we need to store the pattern of the last insn in the
2358 sequence into INSN similarly to the normal case. LAST
2359 should not have REG_NOTES, but we allow them if INSN has
2361 if (REG_NOTES (last) && REG_NOTES (insn))
2363 if (REG_NOTES (last))
2364 REG_NOTES (insn) = REG_NOTES (last);
2365 PATTERN (insn) = PATTERN (last);
2370 PATTERN (insn) = PATTERN (pat);
2375 /* Otherwise, storing into VAR must be handled specially
2376 by storing into a temporary and copying that into VAR
2377 with a new insn after this one. Note that this case
2378 will be used when storing into a promoted scalar since
2379 the insn will now have different modes on the input
2380 and output and hence will be invalid (except for the case
2381 of setting it to a constant, which does not need any
2382 change if it is valid). We generate extra code in that case,
2383 but combine.c will eliminate it. */
2388 rtx fixeddest = SET_DEST (x);
2389 enum machine_mode temp_mode;
2391 /* STRICT_LOW_PART can be discarded, around a MEM. */
2392 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2393 fixeddest = XEXP (fixeddest, 0);
2394 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2395 if (GET_CODE (fixeddest) == SUBREG)
2397 fixeddest = fixup_memory_subreg (fixeddest, insn,
2399 temp_mode = GET_MODE (fixeddest);
2403 fixeddest = fixup_stack_1 (fixeddest, insn);
2404 temp_mode = promoted_mode;
2407 temp = gen_reg_rtx (temp_mode);
2409 emit_insn_after (gen_move_insn (fixeddest,
2410 gen_lowpart (GET_MODE (fixeddest),
2414 SET_DEST (x) = temp;
2422 /* Nothing special about this RTX; fix its operands. */
2424 fmt = GET_RTX_FORMAT (code);
2425 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2428 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2430 else if (fmt[i] == 'E')
2433 for (j = 0; j < XVECLEN (x, i); j++)
2434 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2435 insn, replacements, no_share);
2440 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2441 The REG was placed on the stack, so X now has the form (SUBREG:m1
2444 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2445 must be emitted to compute NEWADDR, put them before INSN.
2447 UNCRITICAL nonzero means accept paradoxical subregs.
2448 This is used for subregs found inside REG_NOTES. */
2451 fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode, int uncritical)
2454 rtx mem = SUBREG_REG (x);
2455 rtx addr = XEXP (mem, 0);
2456 enum machine_mode mode = GET_MODE (x);
2459 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2460 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2463 offset = SUBREG_BYTE (x);
2464 if (BYTES_BIG_ENDIAN)
2465 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2466 the offset so that it points to the right location within the
2468 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2470 if (!flag_force_addr
2471 && memory_address_p (mode, plus_constant (addr, offset)))
2472 /* Shortcut if no insns need be emitted. */
2473 return adjust_address (mem, mode, offset);
2476 result = adjust_address (mem, mode, offset);
2480 emit_insn_before (seq, insn);
2484 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2485 Replace subexpressions of X in place.
2486 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2487 Otherwise return X, with its contents possibly altered.
2489 INSN, PROMOTED_MODE and UNCRITICAL are as for
2490 fixup_memory_subreg. */
2493 walk_fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode,
2503 code = GET_CODE (x);
2505 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2506 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2508 /* Nothing special about this RTX; fix its operands. */
2510 fmt = GET_RTX_FORMAT (code);
2511 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2514 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2515 promoted_mode, uncritical);
2516 else if (fmt[i] == 'E')
2519 for (j = 0; j < XVECLEN (x, i); j++)
2521 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2522 promoted_mode, uncritical);
2528 /* For each memory ref within X, if it refers to a stack slot
2529 with an out of range displacement, put the address in a temp register
2530 (emitting new insns before INSN to load these registers)
2531 and alter the memory ref to use that register.
2532 Replace each such MEM rtx with a copy, to avoid clobberage. */
2535 fixup_stack_1 (rtx x, rtx insn)
2538 RTX_CODE code = GET_CODE (x);
2543 rtx ad = XEXP (x, 0);
2544 /* If we have address of a stack slot but it's not valid
2545 (displacement is too large), compute the sum in a register. */
2546 if (GET_CODE (ad) == PLUS
2547 && GET_CODE (XEXP (ad, 0)) == REG
2548 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2549 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2550 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2551 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2552 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2554 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2555 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2556 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2557 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2560 if (memory_address_p (GET_MODE (x), ad))
2564 temp = copy_to_reg (ad);
2567 emit_insn_before (seq, insn);
2568 return replace_equiv_address (x, temp);
2573 fmt = GET_RTX_FORMAT (code);
2574 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2577 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2578 else if (fmt[i] == 'E')
2581 for (j = 0; j < XVECLEN (x, i); j++)
2582 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2588 /* Optimization: a bit-field instruction whose field
2589 happens to be a byte or halfword in memory
2590 can be changed to a move instruction.
2592 We call here when INSN is an insn to examine or store into a bit-field.
2593 BODY is the SET-rtx to be altered.
2595 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2596 (Currently this is called only from function.c, and EQUIV_MEM
2600 optimize_bit_field (rtx body, rtx insn, rtx *equiv_mem)
2605 enum machine_mode mode;
2607 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2608 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2609 bitfield = SET_DEST (body), destflag = 1;
2611 bitfield = SET_SRC (body), destflag = 0;
2613 /* First check that the field being stored has constant size and position
2614 and is in fact a byte or halfword suitably aligned. */
2616 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2617 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2618 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2620 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2624 /* Now check that the containing word is memory, not a register,
2625 and that it is safe to change the machine mode. */
2627 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2628 memref = XEXP (bitfield, 0);
2629 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2631 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2632 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2633 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2634 memref = SUBREG_REG (XEXP (bitfield, 0));
2635 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2637 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2638 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2641 && ! mode_dependent_address_p (XEXP (memref, 0))
2642 && ! MEM_VOLATILE_P (memref))
2644 /* Now adjust the address, first for any subreg'ing
2645 that we are now getting rid of,
2646 and then for which byte of the word is wanted. */
2648 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2651 /* Adjust OFFSET to count bits from low-address byte. */
2652 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2653 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2654 - offset - INTVAL (XEXP (bitfield, 1)));
2656 /* Adjust OFFSET to count bytes from low-address byte. */
2657 offset /= BITS_PER_UNIT;
2658 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2660 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2661 / UNITS_PER_WORD) * UNITS_PER_WORD;
2662 if (BYTES_BIG_ENDIAN)
2663 offset -= (MIN (UNITS_PER_WORD,
2664 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2665 - MIN (UNITS_PER_WORD,
2666 GET_MODE_SIZE (GET_MODE (memref))));
2670 memref = adjust_address (memref, mode, offset);
2671 insns = get_insns ();
2673 emit_insn_before (insns, insn);
2675 /* Store this memory reference where
2676 we found the bit field reference. */
2680 validate_change (insn, &SET_DEST (body), memref, 1);
2681 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2683 rtx src = SET_SRC (body);
2684 while (GET_CODE (src) == SUBREG
2685 && SUBREG_BYTE (src) == 0)
2686 src = SUBREG_REG (src);
2687 if (GET_MODE (src) != GET_MODE (memref))
2688 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2689 validate_change (insn, &SET_SRC (body), src, 1);
2691 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2692 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2693 /* This shouldn't happen because anything that didn't have
2694 one of these modes should have got converted explicitly
2695 and then referenced through a subreg.
2696 This is so because the original bit-field was
2697 handled by agg_mode and so its tree structure had
2698 the same mode that memref now has. */
2703 rtx dest = SET_DEST (body);
2705 while (GET_CODE (dest) == SUBREG
2706 && SUBREG_BYTE (dest) == 0
2707 && (GET_MODE_CLASS (GET_MODE (dest))
2708 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2709 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2711 dest = SUBREG_REG (dest);
2713 validate_change (insn, &SET_DEST (body), dest, 1);
2715 if (GET_MODE (dest) == GET_MODE (memref))
2716 validate_change (insn, &SET_SRC (body), memref, 1);
2719 /* Convert the mem ref to the destination mode. */
2720 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2723 convert_move (newreg, memref,
2724 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2728 validate_change (insn, &SET_SRC (body), newreg, 1);
2732 /* See if we can convert this extraction or insertion into
2733 a simple move insn. We might not be able to do so if this
2734 was, for example, part of a PARALLEL.
2736 If we succeed, write out any needed conversions. If we fail,
2737 it is hard to guess why we failed, so don't do anything
2738 special; just let the optimization be suppressed. */
2740 if (apply_change_group () && seq)
2741 emit_insn_before (seq, insn);
2746 /* These routines are responsible for converting virtual register references
2747 to the actual hard register references once RTL generation is complete.
2749 The following four variables are used for communication between the
2750 routines. They contain the offsets of the virtual registers from their
2751 respective hard registers. */
2753 static int in_arg_offset;
2754 static int var_offset;
2755 static int dynamic_offset;
2756 static int out_arg_offset;
2757 static int cfa_offset;
2759 /* In most machines, the stack pointer register is equivalent to the bottom
2762 #ifndef STACK_POINTER_OFFSET
2763 #define STACK_POINTER_OFFSET 0
2766 /* If not defined, pick an appropriate default for the offset of dynamically
2767 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2768 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2770 #ifndef STACK_DYNAMIC_OFFSET
2772 /* The bottom of the stack points to the actual arguments. If
2773 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2774 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2775 stack space for register parameters is not pushed by the caller, but
2776 rather part of the fixed stack areas and hence not included in
2777 `current_function_outgoing_args_size'. Nevertheless, we must allow
2778 for it when allocating stack dynamic objects. */
2780 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2781 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2782 ((ACCUMULATE_OUTGOING_ARGS \
2783 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2784 + (STACK_POINTER_OFFSET)) \
2787 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2788 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2789 + (STACK_POINTER_OFFSET))
2793 /* On most machines, the CFA coincides with the first incoming parm. */
2795 #ifndef ARG_POINTER_CFA_OFFSET
2796 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2799 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2800 had its address taken. DECL is the decl or SAVE_EXPR for the
2801 object stored in the register, for later use if we do need to force
2802 REG into the stack. REG is overwritten by the MEM like in
2803 put_reg_into_stack. RESCAN is true if previously emitted
2804 instructions must be rescanned and modified now that the REG has
2805 been transformed. */
2808 gen_mem_addressof (rtx reg, tree decl, int rescan)
2810 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2813 /* Calculate this before we start messing with decl's RTL. */
2814 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2816 /* If the original REG was a user-variable, then so is the REG whose
2817 address is being taken. Likewise for unchanging. */
2818 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2819 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2821 PUT_CODE (reg, MEM);
2822 MEM_ATTRS (reg) = 0;
2827 tree type = TREE_TYPE (decl);
2828 enum machine_mode decl_mode
2829 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2830 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2831 : DECL_RTL_IF_SET (decl));
2833 PUT_MODE (reg, decl_mode);
2835 /* Clear DECL_RTL momentarily so functions below will work
2836 properly, then set it again. */
2837 if (DECL_P (decl) && decl_rtl == reg)
2838 SET_DECL_RTL (decl, 0);
2840 set_mem_attributes (reg, decl, 1);
2841 set_mem_alias_set (reg, set);
2843 if (DECL_P (decl) && decl_rtl == reg)
2844 SET_DECL_RTL (decl, reg);
2847 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0)))
2848 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2851 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2856 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2859 flush_addressof (tree decl)
2861 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2862 && DECL_RTL (decl) != 0
2863 && GET_CODE (DECL_RTL (decl)) == MEM
2864 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2865 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2866 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2869 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2872 put_addressof_into_stack (rtx r, htab_t ht)
2875 int volatile_p, used_p;
2877 rtx reg = XEXP (r, 0);
2879 if (GET_CODE (reg) != REG)
2882 decl = ADDRESSOF_DECL (r);
2885 type = TREE_TYPE (decl);
2886 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2887 && TREE_THIS_VOLATILE (decl));
2888 used_p = (TREE_USED (decl)
2889 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2898 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2899 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2902 /* List of replacements made below in purge_addressof_1 when creating
2903 bitfield insertions. */
2904 static rtx purge_bitfield_addressof_replacements;
2906 /* List of replacements made below in purge_addressof_1 for patterns
2907 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2908 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2909 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2910 enough in complex cases, e.g. when some field values can be
2911 extracted by usage MEM with narrower mode. */
2912 static rtx purge_addressof_replacements;
2914 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2915 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2916 the stack. If the function returns FALSE then the replacement could not
2917 be made. If MAY_POSTPONE is true and we would not put the addressof
2918 to stack, postpone processing of the insn. */
2921 purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
2930 /* Re-start here to avoid recursion in common cases. */
2937 code = GET_CODE (x);
2939 /* If we don't return in any of the cases below, we will recurse inside
2940 the RTX, which will normally result in any ADDRESSOF being forced into
2944 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1,
2946 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0,
2950 else if (code == ADDRESSOF)
2954 if (GET_CODE (XEXP (x, 0)) != MEM)
2955 put_addressof_into_stack (x, ht);
2957 /* We must create a copy of the rtx because it was created by
2958 overwriting a REG rtx which is always shared. */
2959 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2960 if (validate_change (insn, loc, sub, 0)
2961 || validate_replace_rtx (x, sub, insn))
2966 /* If SUB is a hard or virtual register, try it as a pseudo-register.
2967 Otherwise, perhaps SUB is an expression, so generate code to compute
2969 if (GET_CODE (sub) == REG && REGNO (sub) <= LAST_VIRTUAL_REGISTER)
2970 sub = copy_to_reg (sub);
2972 sub = force_operand (sub, NULL_RTX);
2974 if (! validate_change (insn, loc, sub, 0)
2975 && ! validate_replace_rtx (x, sub, insn))
2978 insns = get_insns ();
2980 emit_insn_before (insns, insn);
2984 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2986 rtx sub = XEXP (XEXP (x, 0), 0);
2988 if (GET_CODE (sub) == MEM)
2989 sub = adjust_address_nv (sub, GET_MODE (x), 0);
2990 else if (GET_CODE (sub) == REG
2991 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
2993 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
2995 int size_x, size_sub;
2999 /* Postpone for now, so that we do not emit bitfield arithmetics
3000 unless there is some benefit from it. */
3001 if (!postponed_insns || XEXP (postponed_insns, 0) != insn)
3002 postponed_insns = alloc_INSN_LIST (insn, postponed_insns);
3008 /* When processing REG_NOTES look at the list of
3009 replacements done on the insn to find the register that X
3013 for (tem = purge_bitfield_addressof_replacements;
3015 tem = XEXP (XEXP (tem, 1), 1))
3016 if (rtx_equal_p (x, XEXP (tem, 0)))
3018 *loc = XEXP (XEXP (tem, 1), 0);
3022 /* See comment for purge_addressof_replacements. */
3023 for (tem = purge_addressof_replacements;
3025 tem = XEXP (XEXP (tem, 1), 1))
3026 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3028 rtx z = XEXP (XEXP (tem, 1), 0);
3030 if (GET_MODE (x) == GET_MODE (z)
3031 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3032 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3035 /* It can happen that the note may speak of things
3036 in a wider (or just different) mode than the
3037 code did. This is especially true of
3040 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3043 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3044 && (GET_MODE_SIZE (GET_MODE (x))
3045 > GET_MODE_SIZE (GET_MODE (z))))
3047 /* This can occur as a result in invalid
3048 pointer casts, e.g. float f; ...
3049 *(long long int *)&f.
3050 ??? We could emit a warning here, but
3051 without a line number that wouldn't be
3053 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3056 z = gen_lowpart (GET_MODE (x), z);
3062 /* When we are processing the REG_NOTES of the last instruction
3063 of a libcall, there will be typically no replacements
3064 for that insn; the replacements happened before, piecemeal
3065 fashion. OTOH we are not interested in the details of
3066 this for the REG_EQUAL note, we want to know the big picture,
3067 which can be succinctly described with a simple SUBREG.
3068 Note that removing the REG_EQUAL note is not an option
3069 on the last insn of a libcall, so we must do a replacement. */
3070 if (! purge_addressof_replacements
3071 && ! purge_bitfield_addressof_replacements)
3073 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
3075 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
3076 [0 S8 A32]), which can be expressed with a simple
3078 if ((GET_MODE_SIZE (GET_MODE (x))
3079 == GET_MODE_SIZE (GET_MODE (sub)))
3080 /* Again, invalid pointer casts (as in
3081 compile/990203-1.c) can require paradoxical
3083 || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3084 && (GET_MODE_SIZE (GET_MODE (x))
3085 > GET_MODE_SIZE (GET_MODE (sub)))))
3087 *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
3090 /* ??? Are there other cases we should handle? */
3092 /* Sometimes we may not be able to find the replacement. For
3093 example when the original insn was a MEM in a wider mode,
3094 and the note is part of a sign extension of a narrowed
3095 version of that MEM. Gcc testcase compile/990829-1.c can
3096 generate an example of this situation. Rather than complain
3097 we return false, which will prompt our caller to remove the
3102 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3103 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3105 /* Do not frob unchanging MEMs. If a later reference forces the
3106 pseudo to the stack, we can wind up with multiple writes to
3107 an unchanging memory, which is invalid. */
3108 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3111 /* Don't even consider working with paradoxical subregs,
3112 or the moral equivalent seen here. */
3113 else if (size_x <= size_sub
3114 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3116 /* Do a bitfield insertion to mirror what would happen
3123 rtx p = PREV_INSN (insn);
3126 val = gen_reg_rtx (GET_MODE (x));
3127 if (! validate_change (insn, loc, val, 0))
3129 /* Discard the current sequence and put the
3130 ADDRESSOF on stack. */
3136 emit_insn_before (seq, insn);
3137 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3141 store_bit_field (sub, size_x, 0, GET_MODE (x),
3142 val, GET_MODE_SIZE (GET_MODE (sub)));
3144 /* Make sure to unshare any shared rtl that store_bit_field
3145 might have created. */
3146 unshare_all_rtl_again (get_insns ());
3150 p = emit_insn_after (seq, insn);
3151 if (NEXT_INSN (insn))
3152 compute_insns_for_mem (NEXT_INSN (insn),
3153 p ? NEXT_INSN (p) : NULL_RTX,
3158 rtx p = PREV_INSN (insn);
3161 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3162 GET_MODE (x), GET_MODE (x),
3163 GET_MODE_SIZE (GET_MODE (sub)));
3165 if (! validate_change (insn, loc, val, 0))
3167 /* Discard the current sequence and put the
3168 ADDRESSOF on stack. */
3175 emit_insn_before (seq, insn);
3176 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3180 /* Remember the replacement so that the same one can be done
3181 on the REG_NOTES. */
3182 purge_bitfield_addressof_replacements
3183 = gen_rtx_EXPR_LIST (VOIDmode, x,
3186 purge_bitfield_addressof_replacements));
3188 /* We replaced with a reg -- all done. */
3193 else if (validate_change (insn, loc, sub, 0))
3195 /* Remember the replacement so that the same one can be done
3196 on the REG_NOTES. */
3197 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3201 for (tem = purge_addressof_replacements;
3203 tem = XEXP (XEXP (tem, 1), 1))
3204 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3206 XEXP (XEXP (tem, 1), 0) = sub;
3209 purge_addressof_replacements
3210 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3211 gen_rtx_EXPR_LIST (VOIDmode, sub,
3212 purge_addressof_replacements));
3220 /* Scan all subexpressions. */
3221 fmt = GET_RTX_FORMAT (code);
3222 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3225 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0,
3227 else if (*fmt == 'E')
3228 for (j = 0; j < XVECLEN (x, i); j++)
3229 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0,
3236 /* Return a hash value for K, a REG. */
3239 insns_for_mem_hash (const void *k)
3241 /* Use the address of the key for the hash value. */
3242 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3243 return htab_hash_pointer (m->key);
3246 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3249 insns_for_mem_comp (const void *k1, const void *k2)
3251 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3252 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3253 return m1->key == m2->key;
3256 struct insns_for_mem_walk_info
3258 /* The hash table that we are using to record which INSNs use which
3262 /* The INSN we are currently processing. */
3265 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3266 to find the insns that use the REGs in the ADDRESSOFs. */
3270 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3271 that might be used in an ADDRESSOF expression, record this INSN in
3272 the hash table given by DATA (which is really a pointer to an
3273 insns_for_mem_walk_info structure). */
3276 insns_for_mem_walk (rtx *r, void *data)
3278 struct insns_for_mem_walk_info *ifmwi
3279 = (struct insns_for_mem_walk_info *) data;
3280 struct insns_for_mem_entry tmp;
3281 tmp.insns = NULL_RTX;
3283 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3284 && GET_CODE (XEXP (*r, 0)) == REG)
3287 tmp.key = XEXP (*r, 0);
3288 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3291 *e = ggc_alloc (sizeof (tmp));
3292 memcpy (*e, &tmp, sizeof (tmp));
3295 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3297 struct insns_for_mem_entry *ifme;
3299 ifme = htab_find (ifmwi->ht, &tmp);
3301 /* If we have not already recorded this INSN, do so now. Since
3302 we process the INSNs in order, we know that if we have
3303 recorded it it must be at the front of the list. */
3304 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3305 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3312 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3313 which REGs in HT. */
3316 compute_insns_for_mem (rtx insns, rtx last_insn, htab_t ht)
3319 struct insns_for_mem_walk_info ifmwi;
3322 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3323 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3327 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3331 /* Helper function for purge_addressof called through for_each_rtx.
3332 Returns true iff the rtl is an ADDRESSOF. */
3335 is_addressof (rtx *rtl, void *data ATTRIBUTE_UNUSED)
3337 return GET_CODE (*rtl) == ADDRESSOF;
3340 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3341 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3345 purge_addressof (rtx insns)
3350 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3351 requires a fixup pass over the instruction stream to correct
3352 INSNs that depended on the REG being a REG, and not a MEM. But,
3353 these fixup passes are slow. Furthermore, most MEMs are not
3354 mentioned in very many instructions. So, we speed up the process
3355 by pre-calculating which REGs occur in which INSNs; that allows
3356 us to perform the fixup passes much more quickly. */
3357 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3358 compute_insns_for_mem (insns, NULL_RTX, ht);
3360 postponed_insns = NULL;
3362 for (insn = insns; insn; insn = NEXT_INSN (insn))
3365 if (! purge_addressof_1 (&PATTERN (insn), insn,
3366 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht))
3367 /* If we could not replace the ADDRESSOFs in the insn,
3368 something is wrong. */
3371 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht))
3373 /* If we could not replace the ADDRESSOFs in the insn's notes,
3374 we can just remove the offending notes instead. */
3377 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3379 /* If we find a REG_RETVAL note then the insn is a libcall.
3380 Such insns must have REG_EQUAL notes as well, in order
3381 for later passes of the compiler to work. So it is not
3382 safe to delete the notes here, and instead we abort. */
3383 if (REG_NOTE_KIND (note) == REG_RETVAL)
3385 if (for_each_rtx (¬e, is_addressof, NULL))
3386 remove_note (insn, note);
3391 /* Process the postponed insns. */
3392 while (postponed_insns)
3394 insn = XEXP (postponed_insns, 0);
3395 tmp = postponed_insns;
3396 postponed_insns = XEXP (postponed_insns, 1);
3397 free_INSN_LIST_node (tmp);
3399 if (! purge_addressof_1 (&PATTERN (insn), insn,
3400 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht))
3405 purge_bitfield_addressof_replacements = 0;
3406 purge_addressof_replacements = 0;
3408 /* REGs are shared. purge_addressof will destructively replace a REG
3409 with a MEM, which creates shared MEMs.
3411 Unfortunately, the children of put_reg_into_stack assume that MEMs
3412 referring to the same stack slot are shared (fixup_var_refs and
3413 the associated hash table code).
3415 So, we have to do another unsharing pass after we have flushed any
3416 REGs that had their address taken into the stack.
3418 It may be worth tracking whether or not we converted any REGs into
3419 MEMs to avoid this overhead when it is not needed. */
3420 unshare_all_rtl_again (get_insns ());
3423 /* Convert a SET of a hard subreg to a set of the appropriate hard
3424 register. A subroutine of purge_hard_subreg_sets. */
3427 purge_single_hard_subreg_set (rtx pattern)
3429 rtx reg = SET_DEST (pattern);
3430 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3433 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3434 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3436 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3437 GET_MODE (SUBREG_REG (reg)),
3440 reg = SUBREG_REG (reg);
3444 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3446 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3447 SET_DEST (pattern) = reg;
3451 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3452 only such SETs that we expect to see are those left in because
3453 integrate can't handle sets of parts of a return value register.
3455 We don't use alter_subreg because we only want to eliminate subregs
3456 of hard registers. */
3459 purge_hard_subreg_sets (rtx insn)
3461 for (; insn; insn = NEXT_INSN (insn))
3465 rtx pattern = PATTERN (insn);
3466 switch (GET_CODE (pattern))
3469 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3470 purge_single_hard_subreg_set (pattern);
3475 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3477 rtx inner_pattern = XVECEXP (pattern, 0, j);
3478 if (GET_CODE (inner_pattern) == SET
3479 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3480 purge_single_hard_subreg_set (inner_pattern);
3491 /* Pass through the INSNS of function FNDECL and convert virtual register
3492 references to hard register references. */
3495 instantiate_virtual_regs (tree fndecl, rtx insns)
3500 /* Compute the offsets to use for this function. */
3501 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3502 var_offset = STARTING_FRAME_OFFSET;
3503 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3504 out_arg_offset = STACK_POINTER_OFFSET;
3505 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3507 /* Scan all variables and parameters of this function. For each that is
3508 in memory, instantiate all virtual registers if the result is a valid
3509 address. If not, we do it later. That will handle most uses of virtual
3510 regs on many machines. */
3511 instantiate_decls (fndecl, 1);
3513 /* Initialize recognition, indicating that volatile is OK. */
3516 /* Scan through all the insns, instantiating every virtual register still
3518 for (insn = insns; insn; insn = NEXT_INSN (insn))
3519 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3520 || GET_CODE (insn) == CALL_INSN)
3522 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3523 if (INSN_DELETED_P (insn))
3525 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3526 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3527 if (GET_CODE (insn) == CALL_INSN)
3528 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3531 /* Past this point all ASM statements should match. Verify that
3532 to avoid failures later in the compilation process. */
3533 if (asm_noperands (PATTERN (insn)) >= 0
3534 && ! check_asm_operands (PATTERN (insn)))
3535 instantiate_virtual_regs_lossage (insn);
3538 /* Instantiate the stack slots for the parm registers, for later use in
3539 addressof elimination. */
3540 for (i = 0; i < max_parm_reg; ++i)
3541 if (parm_reg_stack_loc[i])
3542 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3544 /* Now instantiate the remaining register equivalences for debugging info.
3545 These will not be valid addresses. */
3546 instantiate_decls (fndecl, 0);
3548 /* Indicate that, from now on, assign_stack_local should use
3549 frame_pointer_rtx. */
3550 virtuals_instantiated = 1;
3553 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3554 all virtual registers in their DECL_RTL's.
3556 If VALID_ONLY, do this only if the resulting address is still valid.
3557 Otherwise, always do it. */
3560 instantiate_decls (tree fndecl, int valid_only)
3564 /* Process all parameters of the function. */
3565 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3567 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3568 HOST_WIDE_INT size_rtl;
3570 instantiate_decl (DECL_RTL (decl), size, valid_only);
3572 /* If the parameter was promoted, then the incoming RTL mode may be
3573 larger than the declared type size. We must use the larger of
3575 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3576 size = MAX (size_rtl, size);
3577 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3580 /* Now process all variables defined in the function or its subblocks. */
3581 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3584 /* Subroutine of instantiate_decls: Process all decls in the given
3585 BLOCK node and all its subblocks. */
3588 instantiate_decls_1 (tree let, int valid_only)
3592 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3593 if (DECL_RTL_SET_P (t))
3594 instantiate_decl (DECL_RTL (t),
3595 int_size_in_bytes (TREE_TYPE (t)),
3598 /* Process all subblocks. */
3599 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3600 instantiate_decls_1 (t, valid_only);
3603 /* Subroutine of the preceding procedures: Given RTL representing a
3604 decl and the size of the object, do any instantiation required.
3606 If VALID_ONLY is nonzero, it means that the RTL should only be
3607 changed if the new address is valid. */
3610 instantiate_decl (rtx x, HOST_WIDE_INT size, int valid_only)
3612 enum machine_mode mode;
3615 /* If this is not a MEM, no need to do anything. Similarly if the
3616 address is a constant or a register that is not a virtual register. */
3618 if (x == 0 || GET_CODE (x) != MEM)
3622 if (CONSTANT_P (addr)
3623 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3624 || (GET_CODE (addr) == REG
3625 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3626 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3629 /* If we should only do this if the address is valid, copy the address.
3630 We need to do this so we can undo any changes that might make the
3631 address invalid. This copy is unfortunate, but probably can't be
3635 addr = copy_rtx (addr);
3637 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3639 if (valid_only && size >= 0)
3641 unsigned HOST_WIDE_INT decl_size = size;
3643 /* Now verify that the resulting address is valid for every integer or
3644 floating-point mode up to and including SIZE bytes long. We do this
3645 since the object might be accessed in any mode and frame addresses
3648 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3649 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3650 mode = GET_MODE_WIDER_MODE (mode))
3651 if (! memory_address_p (mode, addr))
3654 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3655 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3656 mode = GET_MODE_WIDER_MODE (mode))
3657 if (! memory_address_p (mode, addr))
3661 /* Put back the address now that we have updated it and we either know
3662 it is valid or we don't care whether it is valid. */
3667 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3668 is a virtual register, return the equivalent hard register and set the
3669 offset indirectly through the pointer. Otherwise, return 0. */
3672 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
3675 HOST_WIDE_INT offset;
3677 if (x == virtual_incoming_args_rtx)
3678 new = arg_pointer_rtx, offset = in_arg_offset;
3679 else if (x == virtual_stack_vars_rtx)
3680 new = frame_pointer_rtx, offset = var_offset;
3681 else if (x == virtual_stack_dynamic_rtx)
3682 new = stack_pointer_rtx, offset = dynamic_offset;
3683 else if (x == virtual_outgoing_args_rtx)
3684 new = stack_pointer_rtx, offset = out_arg_offset;
3685 else if (x == virtual_cfa_rtx)
3686 new = arg_pointer_rtx, offset = cfa_offset;
3695 /* Called when instantiate_virtual_regs has failed to update the instruction.
3696 Usually this means that non-matching instruction has been emit, however for
3697 asm statements it may be the problem in the constraints. */
3699 instantiate_virtual_regs_lossage (rtx insn)
3701 if (asm_noperands (PATTERN (insn)) >= 0)
3703 error_for_asm (insn, "impossible constraint in `asm'");
3709 /* Given a pointer to a piece of rtx and an optional pointer to the
3710 containing object, instantiate any virtual registers present in it.
3712 If EXTRA_INSNS, we always do the replacement and generate
3713 any extra insns before OBJECT. If it zero, we do nothing if replacement
3716 Return 1 if we either had nothing to do or if we were able to do the
3717 needed replacement. Return 0 otherwise; we only return zero if
3718 EXTRA_INSNS is zero.
3720 We first try some simple transformations to avoid the creation of extra
3724 instantiate_virtual_regs_1 (rtx *loc, rtx object, int extra_insns)
3729 HOST_WIDE_INT offset = 0;
3735 /* Re-start here to avoid recursion in common cases. */
3742 /* We may have detected and deleted invalid asm statements. */
3743 if (object && INSN_P (object) && INSN_DELETED_P (object))
3746 code = GET_CODE (x);
3748 /* Check for some special cases. */
3766 /* We are allowed to set the virtual registers. This means that
3767 the actual register should receive the source minus the
3768 appropriate offset. This is used, for example, in the handling
3769 of non-local gotos. */
3770 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3772 rtx src = SET_SRC (x);
3774 /* We are setting the register, not using it, so the relevant
3775 offset is the negative of the offset to use were we using
3778 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3780 /* The only valid sources here are PLUS or REG. Just do
3781 the simplest possible thing to handle them. */
3782 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3784 instantiate_virtual_regs_lossage (object);
3789 if (GET_CODE (src) != REG)
3790 temp = force_operand (src, NULL_RTX);
3793 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3797 emit_insn_before (seq, object);
3800 if (! validate_change (object, &SET_SRC (x), temp, 0)
3802 instantiate_virtual_regs_lossage (object);
3807 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3812 /* Handle special case of virtual register plus constant. */
3813 if (CONSTANT_P (XEXP (x, 1)))
3815 rtx old, new_offset;
3817 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3818 if (GET_CODE (XEXP (x, 0)) == PLUS)
3820 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3822 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3824 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3833 #ifdef POINTERS_EXTEND_UNSIGNED
3834 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3835 we can commute the PLUS and SUBREG because pointers into the
3836 frame are well-behaved. */
3837 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3838 && GET_CODE (XEXP (x, 1)) == CONST_INT
3840 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3842 && validate_change (object, loc,
3843 plus_constant (gen_lowpart (ptr_mode,
3846 + INTVAL (XEXP (x, 1))),
3850 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3852 /* We know the second operand is a constant. Unless the
3853 first operand is a REG (which has been already checked),
3854 it needs to be checked. */
3855 if (GET_CODE (XEXP (x, 0)) != REG)
3863 new_offset = plus_constant (XEXP (x, 1), offset);
3865 /* If the new constant is zero, try to replace the sum with just
3867 if (new_offset == const0_rtx
3868 && validate_change (object, loc, new, 0))
3871 /* Next try to replace the register and new offset.
3872 There are two changes to validate here and we can't assume that
3873 in the case of old offset equals new just changing the register
3874 will yield a valid insn. In the interests of a little efficiency,
3875 however, we only call validate change once (we don't queue up the
3876 changes and then call apply_change_group). */
3880 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3881 : (XEXP (x, 0) = new,
3882 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3890 /* Otherwise copy the new constant into a register and replace
3891 constant with that register. */
3892 temp = gen_reg_rtx (Pmode);
3894 if (validate_change (object, &XEXP (x, 1), temp, 0))
3895 emit_insn_before (gen_move_insn (temp, new_offset), object);
3898 /* If that didn't work, replace this expression with a
3899 register containing the sum. */
3902 new = gen_rtx_PLUS (Pmode, new, new_offset);
3905 temp = force_operand (new, NULL_RTX);
3909 emit_insn_before (seq, object);
3910 if (! validate_change (object, loc, temp, 0)
3911 && ! validate_replace_rtx (x, temp, object))
3913 instantiate_virtual_regs_lossage (object);
3922 /* Fall through to generic two-operand expression case. */
3928 case DIV: case UDIV:
3929 case MOD: case UMOD:
3930 case AND: case IOR: case XOR:
3931 case ROTATERT: case ROTATE:
3932 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3934 case GE: case GT: case GEU: case GTU:
3935 case LE: case LT: case LEU: case LTU:
3936 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3937 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3942 /* Most cases of MEM that convert to valid addresses have already been
3943 handled by our scan of decls. The only special handling we
3944 need here is to make a copy of the rtx to ensure it isn't being
3945 shared if we have to change it to a pseudo.
3947 If the rtx is a simple reference to an address via a virtual register,
3948 it can potentially be shared. In such cases, first try to make it
3949 a valid address, which can also be shared. Otherwise, copy it and
3952 First check for common cases that need no processing. These are
3953 usually due to instantiation already being done on a previous instance
3957 if (CONSTANT_ADDRESS_P (temp)
3958 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3959 || temp == arg_pointer_rtx
3961 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3962 || temp == hard_frame_pointer_rtx
3964 || temp == frame_pointer_rtx)
3967 if (GET_CODE (temp) == PLUS
3968 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3969 && (XEXP (temp, 0) == frame_pointer_rtx
3970 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3971 || XEXP (temp, 0) == hard_frame_pointer_rtx
3973 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3974 || XEXP (temp, 0) == arg_pointer_rtx
3979 if (temp == virtual_stack_vars_rtx
3980 || temp == virtual_incoming_args_rtx
3981 || (GET_CODE (temp) == PLUS
3982 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3983 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3984 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3986 /* This MEM may be shared. If the substitution can be done without
3987 the need to generate new pseudos, we want to do it in place
3988 so all copies of the shared rtx benefit. The call below will
3989 only make substitutions if the resulting address is still
3992 Note that we cannot pass X as the object in the recursive call
3993 since the insn being processed may not allow all valid
3994 addresses. However, if we were not passed on object, we can
3995 only modify X without copying it if X will have a valid
3998 ??? Also note that this can still lose if OBJECT is an insn that
3999 has less restrictions on an address that some other insn.
4000 In that case, we will modify the shared address. This case
4001 doesn't seem very likely, though. One case where this could
4002 happen is in the case of a USE or CLOBBER reference, but we
4003 take care of that below. */
4005 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4006 object ? object : x, 0))
4009 /* Otherwise make a copy and process that copy. We copy the entire
4010 RTL expression since it might be a PLUS which could also be
4012 *loc = x = copy_rtx (x);
4015 /* Fall through to generic unary operation case. */
4018 case STRICT_LOW_PART:
4020 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4021 case SIGN_EXTEND: case ZERO_EXTEND:
4022 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4023 case FLOAT: case FIX:
4024 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4029 case POPCOUNT: case PARITY:
4030 /* These case either have just one operand or we know that we need not
4031 check the rest of the operands. */
4037 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4038 go ahead and make the invalid one, but do it to a copy. For a REG,
4039 just make the recursive call, since there's no chance of a problem. */
4041 if ((GET_CODE (XEXP (x, 0)) == MEM
4042 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4044 || (GET_CODE (XEXP (x, 0)) == REG
4045 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4048 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4053 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4054 in front of this insn and substitute the temporary. */
4055 if ((new = instantiate_new_reg (x, &offset)) != 0)
4057 temp = plus_constant (new, offset);
4058 if (!validate_change (object, loc, temp, 0))
4064 temp = force_operand (temp, NULL_RTX);
4068 emit_insn_before (seq, object);
4069 if (! validate_change (object, loc, temp, 0)
4070 && ! validate_replace_rtx (x, temp, object))
4071 instantiate_virtual_regs_lossage (object);
4078 if (GET_CODE (XEXP (x, 0)) == REG)
4081 else if (GET_CODE (XEXP (x, 0)) == MEM)
4083 /* If we have a (addressof (mem ..)), do any instantiation inside
4084 since we know we'll be making the inside valid when we finally
4085 remove the ADDRESSOF. */
4086 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4095 /* Scan all subexpressions. */
4096 fmt = GET_RTX_FORMAT (code);
4097 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4100 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4103 else if (*fmt == 'E')
4104 for (j = 0; j < XVECLEN (x, i); j++)
4105 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4112 /* Optimization: assuming this function does not receive nonlocal gotos,
4113 delete the handlers for such, as well as the insns to establish
4114 and disestablish them. */
4117 delete_handlers (void)
4120 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4122 /* Delete the handler by turning off the flag that would
4123 prevent jump_optimize from deleting it.
4124 Also permit deletion of the nonlocal labels themselves
4125 if nothing local refers to them. */
4126 if (GET_CODE (insn) == CODE_LABEL)
4130 LABEL_PRESERVE_P (insn) = 0;
4132 /* Remove it from the nonlocal_label list, to avoid confusing
4134 for (t = nonlocal_labels, last_t = 0; t;
4135 last_t = t, t = TREE_CHAIN (t))
4136 if (DECL_RTL (TREE_VALUE (t)) == insn)
4141 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4143 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4146 if (GET_CODE (insn) == INSN)
4150 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4151 if (reg_mentioned_p (t, PATTERN (insn)))
4157 || (nonlocal_goto_stack_level != 0
4158 && reg_mentioned_p (nonlocal_goto_stack_level,
4160 delete_related_insns (insn);
4165 /* Return the first insn following those generated by `assign_parms'. */
4168 get_first_nonparm_insn (void)
4171 return NEXT_INSN (last_parm_insn);
4172 return get_insns ();
4175 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4176 This means a type for which function calls must pass an address to the
4177 function or get an address back from the function.
4178 EXP may be a type node or an expression (whose type is tested). */
4181 aggregate_value_p (tree exp, tree fntype)
4183 int i, regno, nregs;
4186 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4189 switch (TREE_CODE (fntype))
4192 fntype = get_callee_fndecl (fntype);
4193 fntype = fntype ? TREE_TYPE (fntype) : 0;
4196 fntype = TREE_TYPE (fntype);
4201 case IDENTIFIER_NODE:
4205 /* We don't expect other rtl types here. */
4209 if (TREE_CODE (type) == VOID_TYPE)
4211 if (targetm.calls.return_in_memory (type, fntype))
4213 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4214 and thus can't be returned in registers. */
4215 if (TREE_ADDRESSABLE (type))
4217 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4219 /* Make sure we have suitable call-clobbered regs to return
4220 the value in; if not, we must return it in memory. */
4221 reg = hard_function_value (type, 0, 0);
4223 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4225 if (GET_CODE (reg) != REG)
4228 regno = REGNO (reg);
4229 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4230 for (i = 0; i < nregs; i++)
4231 if (! call_used_regs[regno + i])
4236 /* Assign RTL expressions to the function's parameters.
4237 This may involve copying them into registers and using
4238 those registers as the RTL for them. */
4241 assign_parms (tree fndecl)
4244 CUMULATIVE_ARGS args_so_far;
4245 /* Total space needed so far for args on the stack,
4246 given as a constant and a tree-expression. */
4247 struct args_size stack_args_size;
4248 tree fntype = TREE_TYPE (fndecl);
4249 tree fnargs = DECL_ARGUMENTS (fndecl), orig_fnargs;
4250 /* This is used for the arg pointer when referring to stack args. */
4251 rtx internal_arg_pointer;
4252 /* This is a dummy PARM_DECL that we used for the function result if
4253 the function returns a structure. */
4254 tree function_result_decl = 0;
4255 int varargs_setup = 0;
4256 int reg_parm_stack_space = 0;
4257 rtx conversion_insns = 0;
4259 /* Nonzero if function takes extra anonymous args.
4260 This means the last named arg must be on the stack
4261 right before the anonymous ones. */
4263 = (TYPE_ARG_TYPES (fntype) != 0
4264 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4265 != void_type_node));
4267 current_function_stdarg = stdarg;
4269 /* If the reg that the virtual arg pointer will be translated into is
4270 not a fixed reg or is the stack pointer, make a copy of the virtual
4271 arg pointer, and address parms via the copy. The frame pointer is
4272 considered fixed even though it is not marked as such.
4274 The second time through, simply use ap to avoid generating rtx. */
4276 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4277 || ! (fixed_regs[ARG_POINTER_REGNUM]
4278 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4279 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4281 internal_arg_pointer = virtual_incoming_args_rtx;
4282 current_function_internal_arg_pointer = internal_arg_pointer;
4284 stack_args_size.constant = 0;
4285 stack_args_size.var = 0;
4287 /* If struct value address is treated as the first argument, make it so. */
4288 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
4289 && ! current_function_returns_pcc_struct
4290 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
4292 tree type = build_pointer_type (TREE_TYPE (fntype));
4294 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4296 DECL_ARG_TYPE (function_result_decl) = type;
4297 TREE_CHAIN (function_result_decl) = fnargs;
4298 fnargs = function_result_decl;
4301 orig_fnargs = fnargs;
4303 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4304 parm_reg_stack_loc = ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4306 if (SPLIT_COMPLEX_ARGS)
4307 fnargs = split_complex_args (fnargs);
4309 #ifdef REG_PARM_STACK_SPACE
4310 #ifdef MAYBE_REG_PARM_STACK_SPACE
4311 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4313 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4317 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4318 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4320 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl);
4323 /* We haven't yet found an argument that we must push and pretend the
4325 current_function_pretend_args_size = 0;
4327 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4331 enum machine_mode promoted_mode, passed_mode;
4332 enum machine_mode nominal_mode, promoted_nominal_mode;
4334 struct locate_and_pad_arg_data locate;
4335 int passed_pointer = 0;
4336 int did_conversion = 0;
4337 tree passed_type = DECL_ARG_TYPE (parm);
4338 tree nominal_type = TREE_TYPE (parm);
4339 int last_named = 0, named_arg;
4343 /* Set LAST_NAMED if this is last named arg before last
4349 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4350 if (DECL_NAME (tem))
4356 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4357 most machines, if this is a varargs/stdarg function, then we treat
4358 the last named arg as if it were anonymous too. */
4359 named_arg = targetm.calls.strict_argument_naming (&args_so_far) ? 1 : ! last_named;
4361 if (TREE_TYPE (parm) == error_mark_node
4362 /* This can happen after weird syntax errors
4363 or if an enum type is defined among the parms. */
4364 || TREE_CODE (parm) != PARM_DECL
4365 || passed_type == NULL)
4367 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4368 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4369 TREE_USED (parm) = 1;
4373 /* Find mode of arg as it is passed, and mode of arg
4374 as it should be during execution of this function. */
4375 passed_mode = TYPE_MODE (passed_type);
4376 nominal_mode = TYPE_MODE (nominal_type);
4378 /* If the parm's mode is VOID, its value doesn't matter,
4379 and avoid the usual things like emit_move_insn that could crash. */
4380 if (nominal_mode == VOIDmode)
4382 SET_DECL_RTL (parm, const0_rtx);
4383 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4387 /* If the parm is to be passed as a transparent union, use the
4388 type of the first field for the tests below. We have already
4389 verified that the modes are the same. */
4390 if (DECL_TRANSPARENT_UNION (parm)
4391 || (TREE_CODE (passed_type) == UNION_TYPE
4392 && TYPE_TRANSPARENT_UNION (passed_type)))
4393 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4395 /* See if this arg was passed by invisible reference. It is if
4396 it is an object whose size depends on the contents of the
4397 object itself or if the machine requires these objects be passed
4400 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type))
4401 || TREE_ADDRESSABLE (passed_type)
4402 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4403 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4404 passed_type, named_arg)
4408 passed_type = nominal_type = build_pointer_type (passed_type);
4410 passed_mode = nominal_mode = Pmode;
4412 /* See if the frontend wants to pass this by invisible reference. */
4413 else if (passed_type != nominal_type
4414 && POINTER_TYPE_P (passed_type)
4415 && TREE_TYPE (passed_type) == nominal_type)
4417 nominal_type = passed_type;
4419 passed_mode = nominal_mode = Pmode;
4422 promoted_mode = passed_mode;
4424 if (targetm.calls.promote_function_args (TREE_TYPE (fndecl)))
4426 /* Compute the mode in which the arg is actually extended to. */
4427 unsignedp = TREE_UNSIGNED (passed_type);
4428 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4431 /* Let machine desc say which reg (if any) the parm arrives in.
4432 0 means it arrives on the stack. */
4433 #ifdef FUNCTION_INCOMING_ARG
4434 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4435 passed_type, named_arg);
4437 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4438 passed_type, named_arg);
4441 if (entry_parm == 0)
4442 promoted_mode = passed_mode;
4444 /* If this is the last named parameter, do any required setup for
4445 varargs or stdargs. We need to know about the case of this being an
4446 addressable type, in which case we skip the registers it
4447 would have arrived in.
4449 For stdargs, LAST_NAMED will be set for two parameters, the one that
4450 is actually the last named, and the dummy parameter. We only
4451 want to do this action once.
4453 Also, indicate when RTL generation is to be suppressed. */
4454 if (last_named && !varargs_setup)
4456 targetm.calls.setup_incoming_varargs (&args_so_far, promoted_mode,
4458 ¤t_function_pretend_args_size, 0);
4462 /* Determine parm's home in the stack,
4463 in case it arrives in the stack or we should pretend it did.
4465 Compute the stack position and rtx where the argument arrives
4468 There is one complexity here: If this was a parameter that would
4469 have been passed in registers, but wasn't only because it is
4470 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4471 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4472 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4473 0 as it was the previous time. */
4474 in_regs = entry_parm != 0;
4475 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4478 if (!in_regs && !named_arg)
4481 targetm.calls.pretend_outgoing_varargs_named (&args_so_far);
4484 #ifdef FUNCTION_INCOMING_ARG
4485 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4487 pretend_named) != 0;
4489 in_regs = FUNCTION_ARG (args_so_far, promoted_mode,
4491 pretend_named) != 0;
4496 /* If this parameter was passed both in registers and in the stack,
4497 use the copy on the stack. */
4498 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4501 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4503 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4504 passed_type, named_arg);
4507 memset (&locate, 0, sizeof (locate));
4508 locate_and_pad_parm (promoted_mode, passed_type, in_regs,
4509 entry_parm ? partial : 0, fndecl,
4510 &stack_args_size, &locate);
4515 /* If we're passing this arg using a reg, make its stack home
4516 the aligned stack slot. */
4518 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset);
4520 offset_rtx = ARGS_SIZE_RTX (locate.offset);
4522 if (offset_rtx == const0_rtx)
4523 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4525 stack_parm = gen_rtx_MEM (promoted_mode,
4526 gen_rtx_PLUS (Pmode,
4527 internal_arg_pointer,
4530 set_mem_attributes (stack_parm, parm, 1);
4531 if (entry_parm && MEM_ATTRS (stack_parm)->align < PARM_BOUNDARY)
4532 set_mem_align (stack_parm, PARM_BOUNDARY);
4534 /* Set also REG_ATTRS if parameter was passed in a register. */
4536 set_reg_attrs_for_parm (entry_parm, stack_parm);
4539 /* If this parm was passed part in regs and part in memory,
4540 pretend it arrived entirely in memory
4541 by pushing the register-part onto the stack.
4543 In the special case of a DImode or DFmode that is split,
4544 we could put it together in a pseudoreg directly,
4545 but for now that's not worth bothering with. */
4549 #ifndef MAYBE_REG_PARM_STACK_SPACE
4550 /* When REG_PARM_STACK_SPACE is nonzero, stack space for
4551 split parameters was allocated by our caller, so we
4552 won't be pushing it in the prolog. */
4553 if (reg_parm_stack_space == 0)
4555 current_function_pretend_args_size
4556 = (((partial * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4557 / (PARM_BOUNDARY / BITS_PER_UNIT)
4558 * (PARM_BOUNDARY / BITS_PER_UNIT));
4560 /* Handle calls that pass values in multiple non-contiguous
4561 locations. The Irix 6 ABI has examples of this. */
4562 if (GET_CODE (entry_parm) == PARALLEL)
4563 emit_group_store (validize_mem (stack_parm), entry_parm,
4565 int_size_in_bytes (TREE_TYPE (parm)));
4568 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
4571 entry_parm = stack_parm;
4574 /* If we didn't decide this parm came in a register,
4575 by default it came on the stack. */
4576 if (entry_parm == 0)
4577 entry_parm = stack_parm;
4579 /* Record permanently how this parm was passed. */
4580 DECL_INCOMING_RTL (parm) = entry_parm;
4582 /* If there is actually space on the stack for this parm,
4583 count it in stack_args_size; otherwise set stack_parm to 0
4584 to indicate there is no preallocated stack slot for the parm. */
4586 if (entry_parm == stack_parm
4587 || (GET_CODE (entry_parm) == PARALLEL
4588 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4589 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4590 /* On some machines, even if a parm value arrives in a register
4591 there is still an (uninitialized) stack slot allocated for it.
4593 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4594 whether this parameter already has a stack slot allocated,
4595 because an arg block exists only if current_function_args_size
4596 is larger than some threshold, and we haven't calculated that
4597 yet. So, for now, we just assume that stack slots never exist
4599 || REG_PARM_STACK_SPACE (fndecl) > 0
4603 stack_args_size.constant += locate.size.constant;
4604 /* locate.size doesn't include the part in regs. */
4606 stack_args_size.constant += current_function_pretend_args_size;
4607 if (locate.size.var)
4608 ADD_PARM_SIZE (stack_args_size, locate.size.var);
4611 /* No stack slot was pushed for this parm. */
4614 /* Update info on where next arg arrives in registers. */
4616 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4617 passed_type, named_arg);
4619 /* If we can't trust the parm stack slot to be aligned enough
4620 for its ultimate type, don't use that slot after entry.
4621 We'll make another stack slot, if we need one. */
4623 unsigned int thisparm_boundary
4624 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4626 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4630 /* If parm was passed in memory, and we need to convert it on entry,
4631 don't store it back in that same slot. */
4632 if (entry_parm == stack_parm
4633 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4636 /* When an argument is passed in multiple locations, we can't
4637 make use of this information, but we can save some copying if
4638 the whole argument is passed in a single register. */
4639 if (GET_CODE (entry_parm) == PARALLEL
4640 && nominal_mode != BLKmode && passed_mode != BLKmode)
4642 int i, len = XVECLEN (entry_parm, 0);
4644 for (i = 0; i < len; i++)
4645 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4646 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4647 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4649 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4651 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4652 DECL_INCOMING_RTL (parm) = entry_parm;
4657 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4658 in the mode in which it arrives.
4659 STACK_PARM is an RTX for a stack slot where the parameter can live
4660 during the function (in case we want to put it there).
4661 STACK_PARM is 0 if no stack slot was pushed for it.
4663 Now output code if necessary to convert ENTRY_PARM to
4664 the type in which this function declares it,
4665 and store that result in an appropriate place,
4666 which may be a pseudo reg, may be STACK_PARM,
4667 or may be a local stack slot if STACK_PARM is 0.
4669 Set DECL_RTL to that place. */
4671 if (nominal_mode == BLKmode
4672 #ifdef BLOCK_REG_PADDING
4673 || (locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward)
4674 && GET_MODE_SIZE (promoted_mode) < UNITS_PER_WORD)
4676 || GET_CODE (entry_parm) == PARALLEL)
4678 /* If a BLKmode arrives in registers, copy it to a stack slot.
4679 Handle calls that pass values in multiple non-contiguous
4680 locations. The Irix 6 ABI has examples of this. */
4681 if (GET_CODE (entry_parm) == REG
4682 || GET_CODE (entry_parm) == PARALLEL)
4684 int size = int_size_in_bytes (TREE_TYPE (parm));
4685 int size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
4688 /* Note that we will be storing an integral number of words.
4689 So we have to be careful to ensure that we allocate an
4690 integral number of words. We do this below in the
4691 assign_stack_local if space was not allocated in the argument
4692 list. If it was, this will not work if PARM_BOUNDARY is not
4693 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4694 if it becomes a problem. */
4696 if (stack_parm == 0)
4698 stack_parm = assign_stack_local (BLKmode, size_stored, 0);
4699 PUT_MODE (stack_parm, GET_MODE (entry_parm));
4700 set_mem_attributes (stack_parm, parm, 1);
4703 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4706 mem = validize_mem (stack_parm);
4708 /* Handle calls that pass values in multiple non-contiguous
4709 locations. The Irix 6 ABI has examples of this. */
4710 if (GET_CODE (entry_parm) == PARALLEL)
4711 emit_group_store (mem, entry_parm, TREE_TYPE (parm), size);
4716 /* If SIZE is that of a mode no bigger than a word, just use
4717 that mode's store operation. */
4718 else if (size <= UNITS_PER_WORD)
4720 enum machine_mode mode
4721 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
4724 #ifdef BLOCK_REG_PADDING
4725 && (size == UNITS_PER_WORD
4726 || (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4727 != (BYTES_BIG_ENDIAN ? upward : downward)))
4731 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
4732 emit_move_insn (change_address (mem, mode, 0), reg);
4735 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
4736 machine must be aligned to the left before storing
4737 to memory. Note that the previous test doesn't
4738 handle all cases (e.g. SIZE == 3). */
4739 else if (size != UNITS_PER_WORD
4740 #ifdef BLOCK_REG_PADDING
4741 && (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4749 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4750 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
4752 x = expand_binop (word_mode, ashl_optab, reg,
4753 GEN_INT (by), 0, 1, OPTAB_WIDEN);
4754 tem = change_address (mem, word_mode, 0);
4755 emit_move_insn (tem, x);
4758 move_block_from_reg (REGNO (entry_parm), mem,
4759 size_stored / UNITS_PER_WORD);
4762 move_block_from_reg (REGNO (entry_parm), mem,
4763 size_stored / UNITS_PER_WORD);
4765 SET_DECL_RTL (parm, stack_parm);
4767 else if (! ((! optimize
4768 && ! DECL_REGISTER (parm))
4769 || TREE_SIDE_EFFECTS (parm)
4770 /* If -ffloat-store specified, don't put explicit
4771 float variables into registers. */
4772 || (flag_float_store
4773 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4774 /* Always assign pseudo to structure return or item passed
4775 by invisible reference. */
4776 || passed_pointer || parm == function_result_decl)
4778 /* Store the parm in a pseudoregister during the function, but we
4779 may need to do it in a wider mode. */
4782 unsigned int regno, regnoi = 0, regnor = 0;
4784 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4786 promoted_nominal_mode
4787 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4789 parmreg = gen_reg_rtx (promoted_nominal_mode);
4790 mark_user_reg (parmreg);
4792 /* If this was an item that we received a pointer to, set DECL_RTL
4796 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4798 set_mem_attributes (x, parm, 1);
4799 SET_DECL_RTL (parm, x);
4803 SET_DECL_RTL (parm, parmreg);
4804 maybe_set_unchanging (DECL_RTL (parm), parm);
4807 /* Copy the value into the register. */
4808 if (nominal_mode != passed_mode
4809 || promoted_nominal_mode != promoted_mode)
4812 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4813 mode, by the caller. We now have to convert it to
4814 NOMINAL_MODE, if different. However, PARMREG may be in
4815 a different mode than NOMINAL_MODE if it is being stored
4818 If ENTRY_PARM is a hard register, it might be in a register
4819 not valid for operating in its mode (e.g., an odd-numbered
4820 register for a DFmode). In that case, moves are the only
4821 thing valid, so we can't do a convert from there. This
4822 occurs when the calling sequence allow such misaligned
4825 In addition, the conversion may involve a call, which could
4826 clobber parameters which haven't been copied to pseudo
4827 registers yet. Therefore, we must first copy the parm to
4828 a pseudo reg here, and save the conversion until after all
4829 parameters have been moved. */
4831 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4833 emit_move_insn (tempreg, validize_mem (entry_parm));
4835 push_to_sequence (conversion_insns);
4836 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4838 if (GET_CODE (tempreg) == SUBREG
4839 && GET_MODE (tempreg) == nominal_mode
4840 && GET_CODE (SUBREG_REG (tempreg)) == REG
4841 && nominal_mode == passed_mode
4842 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4843 && GET_MODE_SIZE (GET_MODE (tempreg))
4844 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4846 /* The argument is already sign/zero extended, so note it
4848 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4849 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4852 /* TREE_USED gets set erroneously during expand_assignment. */
4853 save_tree_used = TREE_USED (parm);
4854 expand_assignment (parm,
4855 make_tree (nominal_type, tempreg), 0);
4856 TREE_USED (parm) = save_tree_used;
4857 conversion_insns = get_insns ();
4862 emit_move_insn (parmreg, validize_mem (entry_parm));
4864 /* If we were passed a pointer but the actual value
4865 can safely live in a register, put it in one. */
4866 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4867 /* If by-reference argument was promoted, demote it. */
4868 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4870 && ! DECL_REGISTER (parm))
4871 || TREE_SIDE_EFFECTS (parm)
4872 /* If -ffloat-store specified, don't put explicit
4873 float variables into registers. */
4874 || (flag_float_store
4875 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4877 /* We can't use nominal_mode, because it will have been set to
4878 Pmode above. We must use the actual mode of the parm. */
4879 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4880 mark_user_reg (parmreg);
4881 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4883 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4884 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4885 push_to_sequence (conversion_insns);
4886 emit_move_insn (tempreg, DECL_RTL (parm));
4888 convert_to_mode (GET_MODE (parmreg),
4891 emit_move_insn (parmreg, DECL_RTL (parm));
4892 conversion_insns = get_insns();
4897 emit_move_insn (parmreg, DECL_RTL (parm));
4898 SET_DECL_RTL (parm, parmreg);
4899 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4903 #ifdef FUNCTION_ARG_CALLEE_COPIES
4904 /* If we are passed an arg by reference and it is our responsibility
4905 to make a copy, do it now.
4906 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4907 original argument, so we must recreate them in the call to
4908 FUNCTION_ARG_CALLEE_COPIES. */
4909 /* ??? Later add code to handle the case that if the argument isn't
4910 modified, don't do the copy. */
4912 else if (passed_pointer
4913 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4914 TYPE_MODE (DECL_ARG_TYPE (parm)),
4915 DECL_ARG_TYPE (parm),
4917 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4920 tree type = DECL_ARG_TYPE (parm);
4922 /* This sequence may involve a library call perhaps clobbering
4923 registers that haven't been copied to pseudos yet. */
4925 push_to_sequence (conversion_insns);
4927 if (!COMPLETE_TYPE_P (type)
4928 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4929 /* This is a variable sized object. */
4930 copy = gen_rtx_MEM (BLKmode,
4931 allocate_dynamic_stack_space
4932 (expr_size (parm), NULL_RTX,
4933 TYPE_ALIGN (type)));
4935 copy = assign_stack_temp (TYPE_MODE (type),
4936 int_size_in_bytes (type), 1);
4937 set_mem_attributes (copy, parm, 1);
4939 store_expr (parm, copy, 0);
4940 emit_move_insn (parmreg, XEXP (copy, 0));
4941 conversion_insns = get_insns ();
4945 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4947 /* In any case, record the parm's desired stack location
4948 in case we later discover it must live in the stack.
4950 If it is a COMPLEX value, store the stack location for both
4953 if (GET_CODE (parmreg) == CONCAT)
4954 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4956 regno = REGNO (parmreg);
4958 if (regno >= max_parm_reg)
4961 int old_max_parm_reg = max_parm_reg;
4963 /* It's slow to expand this one register at a time,
4964 but it's also rare and we need max_parm_reg to be
4965 precisely correct. */
4966 max_parm_reg = regno + 1;
4967 new = ggc_realloc (parm_reg_stack_loc,
4968 max_parm_reg * sizeof (rtx));
4969 memset (new + old_max_parm_reg, 0,
4970 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4971 parm_reg_stack_loc = new;
4974 if (GET_CODE (parmreg) == CONCAT)
4976 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4978 regnor = REGNO (gen_realpart (submode, parmreg));
4979 regnoi = REGNO (gen_imagpart (submode, parmreg));
4981 if (stack_parm != 0)
4983 parm_reg_stack_loc[regnor]
4984 = gen_realpart (submode, stack_parm);
4985 parm_reg_stack_loc[regnoi]
4986 = gen_imagpart (submode, stack_parm);
4990 parm_reg_stack_loc[regnor] = 0;
4991 parm_reg_stack_loc[regnoi] = 0;
4995 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4997 /* Mark the register as eliminable if we did no conversion
4998 and it was copied from memory at a fixed offset,
4999 and the arg pointer was not copied to a pseudo-reg.
5000 If the arg pointer is a pseudo reg or the offset formed
5001 an invalid address, such memory-equivalences
5002 as we make here would screw up life analysis for it. */
5003 if (nominal_mode == passed_mode
5006 && GET_CODE (stack_parm) == MEM
5007 && locate.offset.var == 0
5008 && reg_mentioned_p (virtual_incoming_args_rtx,
5009 XEXP (stack_parm, 0)))
5011 rtx linsn = get_last_insn ();
5014 /* Mark complex types separately. */
5015 if (GET_CODE (parmreg) == CONCAT)
5016 /* Scan backwards for the set of the real and
5018 for (sinsn = linsn; sinsn != 0;
5019 sinsn = prev_nonnote_insn (sinsn))
5021 set = single_set (sinsn);
5023 && SET_DEST (set) == regno_reg_rtx [regnoi])
5025 = gen_rtx_EXPR_LIST (REG_EQUIV,
5026 parm_reg_stack_loc[regnoi],
5029 && SET_DEST (set) == regno_reg_rtx [regnor])
5031 = gen_rtx_EXPR_LIST (REG_EQUIV,
5032 parm_reg_stack_loc[regnor],
5035 else if ((set = single_set (linsn)) != 0
5036 && SET_DEST (set) == parmreg)
5038 = gen_rtx_EXPR_LIST (REG_EQUIV,
5039 stack_parm, REG_NOTES (linsn));
5042 /* For pointer data type, suggest pointer register. */
5043 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5044 mark_reg_pointer (parmreg,
5045 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5047 /* If something wants our address, try to use ADDRESSOF. */
5048 if (TREE_ADDRESSABLE (parm))
5050 /* If we end up putting something into the stack,
5051 fixup_var_refs_insns will need to make a pass over
5052 all the instructions. It looks through the pending
5053 sequences -- but it can't see the ones in the
5054 CONVERSION_INSNS, if they're not on the sequence
5055 stack. So, we go back to that sequence, just so that
5056 the fixups will happen. */
5057 push_to_sequence (conversion_insns);
5058 put_var_into_stack (parm, /*rescan=*/true);
5059 conversion_insns = get_insns ();
5065 /* Value must be stored in the stack slot STACK_PARM
5066 during function execution. */
5068 if (promoted_mode != nominal_mode)
5070 /* Conversion is required. */
5071 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5073 emit_move_insn (tempreg, validize_mem (entry_parm));
5075 push_to_sequence (conversion_insns);
5076 entry_parm = convert_to_mode (nominal_mode, tempreg,
5077 TREE_UNSIGNED (TREE_TYPE (parm)));
5079 /* ??? This may need a big-endian conversion on sparc64. */
5080 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5082 conversion_insns = get_insns ();
5087 if (entry_parm != stack_parm)
5089 if (stack_parm == 0)
5092 = assign_stack_local (GET_MODE (entry_parm),
5093 GET_MODE_SIZE (GET_MODE (entry_parm)),
5095 set_mem_attributes (stack_parm, parm, 1);
5098 if (promoted_mode != nominal_mode)
5100 push_to_sequence (conversion_insns);
5101 emit_move_insn (validize_mem (stack_parm),
5102 validize_mem (entry_parm));
5103 conversion_insns = get_insns ();
5107 emit_move_insn (validize_mem (stack_parm),
5108 validize_mem (entry_parm));
5111 SET_DECL_RTL (parm, stack_parm);
5115 if (SPLIT_COMPLEX_ARGS && fnargs != orig_fnargs)
5117 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
5119 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE)
5122 gen_rtx_CONCAT (DECL_MODE (parm),
5124 DECL_RTL (TREE_CHAIN (fnargs))));
5125 DECL_INCOMING_RTL (parm)
5126 = gen_rtx_CONCAT (DECL_MODE (parm),
5127 DECL_INCOMING_RTL (fnargs),
5128 DECL_INCOMING_RTL (TREE_CHAIN (fnargs)));
5129 fnargs = TREE_CHAIN (fnargs);
5133 SET_DECL_RTL (parm, DECL_RTL (fnargs));
5134 DECL_INCOMING_RTL (parm) = DECL_INCOMING_RTL (fnargs);
5136 fnargs = TREE_CHAIN (fnargs);
5140 /* Output all parameter conversion instructions (possibly including calls)
5141 now that all parameters have been copied out of hard registers. */
5142 emit_insn (conversion_insns);
5144 /* If we are receiving a struct value address as the first argument, set up
5145 the RTL for the function result. As this might require code to convert
5146 the transmitted address to Pmode, we do this here to ensure that possible
5147 preliminary conversions of the address have been emitted already. */
5148 if (function_result_decl)
5150 tree result = DECL_RESULT (fndecl);
5151 rtx addr = DECL_RTL (function_result_decl);
5154 #ifdef POINTERS_EXTEND_UNSIGNED
5155 if (GET_MODE (addr) != Pmode)
5156 addr = convert_memory_address (Pmode, addr);
5159 x = gen_rtx_MEM (DECL_MODE (result), addr);
5160 set_mem_attributes (x, result, 1);
5161 SET_DECL_RTL (result, x);
5164 last_parm_insn = get_last_insn ();
5166 current_function_args_size = stack_args_size.constant;
5168 /* Adjust function incoming argument size for alignment and
5171 #ifdef REG_PARM_STACK_SPACE
5172 #ifndef MAYBE_REG_PARM_STACK_SPACE
5173 current_function_args_size = MAX (current_function_args_size,
5174 REG_PARM_STACK_SPACE (fndecl));
5178 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5180 current_function_args_size
5181 = ((current_function_args_size + STACK_BYTES - 1)
5182 / STACK_BYTES) * STACK_BYTES;
5184 #ifdef ARGS_GROW_DOWNWARD
5185 current_function_arg_offset_rtx
5186 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5187 : expand_expr (size_diffop (stack_args_size.var,
5188 size_int (-stack_args_size.constant)),
5189 NULL_RTX, VOIDmode, 0));
5191 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5194 /* See how many bytes, if any, of its args a function should try to pop
5197 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5198 current_function_args_size);
5200 /* For stdarg.h function, save info about
5201 regs and stack space used by the named args. */
5203 current_function_args_info = args_so_far;
5205 /* Set the rtx used for the function return value. Put this in its
5206 own variable so any optimizers that need this information don't have
5207 to include tree.h. Do this here so it gets done when an inlined
5208 function gets output. */
5210 current_function_return_rtx
5211 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5212 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5214 /* If scalar return value was computed in a pseudo-reg, or was a named
5215 return value that got dumped to the stack, copy that to the hard
5217 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5219 tree decl_result = DECL_RESULT (fndecl);
5220 rtx decl_rtl = DECL_RTL (decl_result);
5222 if (REG_P (decl_rtl)
5223 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5224 : DECL_REGISTER (decl_result))
5228 #ifdef FUNCTION_OUTGOING_VALUE
5229 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5232 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5235 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5236 /* The delay slot scheduler assumes that current_function_return_rtx
5237 holds the hard register containing the return value, not a
5238 temporary pseudo. */
5239 current_function_return_rtx = real_decl_rtl;
5244 /* If ARGS contains entries with complex types, split the entry into two
5245 entries of the component type. Return a new list of substitutions are
5246 needed, else the old list. */
5249 split_complex_args (tree args)
5253 /* Before allocating memory, check for the common case of no complex. */
5254 for (p = args; p; p = TREE_CHAIN (p))
5255 if (TREE_CODE (TREE_TYPE (p)) == COMPLEX_TYPE)
5260 args = copy_list (args);
5262 for (p = args; p; p = TREE_CHAIN (p))
5264 tree type = TREE_TYPE (p);
5265 if (TREE_CODE (type) == COMPLEX_TYPE)
5268 tree subtype = TREE_TYPE (type);
5270 /* Rewrite the PARM_DECL's type with its component. */
5271 TREE_TYPE (p) = subtype;
5272 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
5273 DECL_MODE (p) = VOIDmode;
5274 DECL_SIZE (p) = NULL;
5275 DECL_SIZE_UNIT (p) = NULL;
5278 /* Build a second synthetic decl. */
5279 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
5280 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
5281 layout_decl (decl, 0);
5283 /* Splice it in; skip the new decl. */
5284 TREE_CHAIN (decl) = TREE_CHAIN (p);
5285 TREE_CHAIN (p) = decl;
5293 /* Indicate whether REGNO is an incoming argument to the current function
5294 that was promoted to a wider mode. If so, return the RTX for the
5295 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5296 that REGNO is promoted from and whether the promotion was signed or
5300 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
5304 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5305 arg = TREE_CHAIN (arg))
5306 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5307 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5308 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5310 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5311 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5313 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5314 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5315 && mode != DECL_MODE (arg))
5317 *pmode = DECL_MODE (arg);
5318 *punsignedp = unsignedp;
5319 return DECL_INCOMING_RTL (arg);
5327 /* Compute the size and offset from the start of the stacked arguments for a
5328 parm passed in mode PASSED_MODE and with type TYPE.
5330 INITIAL_OFFSET_PTR points to the current offset into the stacked
5333 The starting offset and size for this parm are returned in
5334 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5335 nonzero, the offset is that of stack slot, which is returned in
5336 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5337 padding required from the initial offset ptr to the stack slot.
5339 IN_REGS is nonzero if the argument will be passed in registers. It will
5340 never be set if REG_PARM_STACK_SPACE is not defined.
5342 FNDECL is the function in which the argument was defined.
5344 There are two types of rounding that are done. The first, controlled by
5345 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5346 list to be aligned to the specific boundary (in bits). This rounding
5347 affects the initial and starting offsets, but not the argument size.
5349 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5350 optionally rounds the size of the parm to PARM_BOUNDARY. The
5351 initial offset is not affected by this rounding, while the size always
5352 is and the starting offset may be. */
5354 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5355 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5356 callers pass in the total size of args so far as
5357 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5360 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
5361 int partial, tree fndecl ATTRIBUTE_UNUSED,
5362 struct args_size *initial_offset_ptr,
5363 struct locate_and_pad_arg_data *locate)
5366 enum direction where_pad;
5368 int reg_parm_stack_space = 0;
5369 int part_size_in_regs;
5371 #ifdef REG_PARM_STACK_SPACE
5372 #ifdef MAYBE_REG_PARM_STACK_SPACE
5373 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5375 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5378 /* If we have found a stack parm before we reach the end of the
5379 area reserved for registers, skip that area. */
5382 if (reg_parm_stack_space > 0)
5384 if (initial_offset_ptr->var)
5386 initial_offset_ptr->var
5387 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5388 ssize_int (reg_parm_stack_space));
5389 initial_offset_ptr->constant = 0;
5391 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5392 initial_offset_ptr->constant = reg_parm_stack_space;
5395 #endif /* REG_PARM_STACK_SPACE */
5397 part_size_in_regs = 0;
5398 if (reg_parm_stack_space == 0)
5399 part_size_in_regs = ((partial * UNITS_PER_WORD)
5400 / (PARM_BOUNDARY / BITS_PER_UNIT)
5401 * (PARM_BOUNDARY / BITS_PER_UNIT));
5404 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5405 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5406 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5407 locate->where_pad = where_pad;
5409 #ifdef ARGS_GROW_DOWNWARD
5410 locate->slot_offset.constant = -initial_offset_ptr->constant;
5411 if (initial_offset_ptr->var)
5412 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
5413 initial_offset_ptr->var);
5417 if (where_pad != none
5418 && (!host_integerp (sizetree, 1)
5419 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5420 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5421 SUB_PARM_SIZE (locate->slot_offset, s2);
5424 locate->slot_offset.constant += part_size_in_regs;
5427 #ifdef REG_PARM_STACK_SPACE
5428 || REG_PARM_STACK_SPACE (fndecl) > 0
5431 pad_to_arg_alignment (&locate->slot_offset, boundary,
5432 &locate->alignment_pad);
5434 locate->size.constant = (-initial_offset_ptr->constant
5435 - locate->slot_offset.constant);
5436 if (initial_offset_ptr->var)
5437 locate->size.var = size_binop (MINUS_EXPR,
5438 size_binop (MINUS_EXPR,
5440 initial_offset_ptr->var),
5441 locate->slot_offset.var);
5443 /* Pad_below needs the pre-rounded size to know how much to pad
5445 locate->offset = locate->slot_offset;
5446 if (where_pad == downward)
5447 pad_below (&locate->offset, passed_mode, sizetree);
5449 #else /* !ARGS_GROW_DOWNWARD */
5451 #ifdef REG_PARM_STACK_SPACE
5452 || REG_PARM_STACK_SPACE (fndecl) > 0
5455 pad_to_arg_alignment (initial_offset_ptr, boundary,
5456 &locate->alignment_pad);
5457 locate->slot_offset = *initial_offset_ptr;
5459 #ifdef PUSH_ROUNDING
5460 if (passed_mode != BLKmode)
5461 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5464 /* Pad_below needs the pre-rounded size to know how much to pad below
5465 so this must be done before rounding up. */
5466 locate->offset = locate->slot_offset;
5467 if (where_pad == downward)
5468 pad_below (&locate->offset, passed_mode, sizetree);
5470 if (where_pad != none
5471 && (!host_integerp (sizetree, 1)
5472 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5473 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5475 ADD_PARM_SIZE (locate->size, sizetree);
5477 locate->size.constant -= part_size_in_regs;
5478 #endif /* ARGS_GROW_DOWNWARD */
5481 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5482 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5485 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
5486 struct args_size *alignment_pad)
5488 tree save_var = NULL_TREE;
5489 HOST_WIDE_INT save_constant = 0;
5491 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5493 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5495 save_var = offset_ptr->var;
5496 save_constant = offset_ptr->constant;
5499 alignment_pad->var = NULL_TREE;
5500 alignment_pad->constant = 0;
5502 if (boundary > BITS_PER_UNIT)
5504 if (offset_ptr->var)
5507 #ifdef ARGS_GROW_DOWNWARD
5512 (ARGS_SIZE_TREE (*offset_ptr),
5513 boundary / BITS_PER_UNIT);
5514 /* ARGS_SIZE_TREE includes constant term. */
5515 offset_ptr->constant = 0;
5516 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5517 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5522 offset_ptr->constant =
5523 #ifdef ARGS_GROW_DOWNWARD
5524 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5526 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5528 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5529 alignment_pad->constant = offset_ptr->constant - save_constant;
5535 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
5537 if (passed_mode != BLKmode)
5539 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5540 offset_ptr->constant
5541 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5542 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5543 - GET_MODE_SIZE (passed_mode));
5547 if (TREE_CODE (sizetree) != INTEGER_CST
5548 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5550 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5551 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5553 ADD_PARM_SIZE (*offset_ptr, s2);
5554 SUB_PARM_SIZE (*offset_ptr, sizetree);
5559 /* Walk the tree of blocks describing the binding levels within a function
5560 and warn about uninitialized variables.
5561 This is done after calling flow_analysis and before global_alloc
5562 clobbers the pseudo-regs to hard regs. */
5565 uninitialized_vars_warning (tree block)
5568 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5570 if (warn_uninitialized
5571 && TREE_CODE (decl) == VAR_DECL
5572 /* These warnings are unreliable for and aggregates
5573 because assigning the fields one by one can fail to convince
5574 flow.c that the entire aggregate was initialized.
5575 Unions are troublesome because members may be shorter. */
5576 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5577 && DECL_RTL (decl) != 0
5578 && GET_CODE (DECL_RTL (decl)) == REG
5579 /* Global optimizations can make it difficult to determine if a
5580 particular variable has been initialized. However, a VAR_DECL
5581 with a nonzero DECL_INITIAL had an initializer, so do not
5582 claim it is potentially uninitialized.
5584 When the DECL_INITIAL is NULL call the language hook to tell us
5585 if we want to warn. */
5586 && (DECL_INITIAL (decl) == NULL_TREE || lang_hooks.decl_uninit (decl))
5587 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5588 warning ("%H'%D' might be used uninitialized in this function",
5589 &DECL_SOURCE_LOCATION (decl), decl);
5591 && TREE_CODE (decl) == VAR_DECL
5592 && DECL_RTL (decl) != 0
5593 && GET_CODE (DECL_RTL (decl)) == REG
5594 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5595 warning ("%Hvariable '%D' might be clobbered by `longjmp' or `vfork'",
5596 &DECL_SOURCE_LOCATION (decl), decl);
5598 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5599 uninitialized_vars_warning (sub);
5602 /* Do the appropriate part of uninitialized_vars_warning
5603 but for arguments instead of local variables. */
5606 setjmp_args_warning (void)
5609 for (decl = DECL_ARGUMENTS (current_function_decl);
5610 decl; decl = TREE_CHAIN (decl))
5611 if (DECL_RTL (decl) != 0
5612 && GET_CODE (DECL_RTL (decl)) == REG
5613 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5614 warning ("%Hargument '%D' might be clobbered by `longjmp' or `vfork'",
5615 &DECL_SOURCE_LOCATION (decl), decl);
5618 /* If this function call setjmp, put all vars into the stack
5619 unless they were declared `register'. */
5622 setjmp_protect (tree block)
5625 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5626 if ((TREE_CODE (decl) == VAR_DECL
5627 || TREE_CODE (decl) == PARM_DECL)
5628 && DECL_RTL (decl) != 0
5629 && (GET_CODE (DECL_RTL (decl)) == REG
5630 || (GET_CODE (DECL_RTL (decl)) == MEM
5631 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5632 /* If this variable came from an inline function, it must be
5633 that its life doesn't overlap the setjmp. If there was a
5634 setjmp in the function, it would already be in memory. We
5635 must exclude such variable because their DECL_RTL might be
5636 set to strange things such as virtual_stack_vars_rtx. */
5637 && ! DECL_FROM_INLINE (decl)
5639 #ifdef NON_SAVING_SETJMP
5640 /* If longjmp doesn't restore the registers,
5641 don't put anything in them. */
5645 ! DECL_REGISTER (decl)))
5646 put_var_into_stack (decl, /*rescan=*/true);
5647 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5648 setjmp_protect (sub);
5651 /* Like the previous function, but for args instead of local variables. */
5654 setjmp_protect_args (void)
5657 for (decl = DECL_ARGUMENTS (current_function_decl);
5658 decl; decl = TREE_CHAIN (decl))
5659 if ((TREE_CODE (decl) == VAR_DECL
5660 || TREE_CODE (decl) == PARM_DECL)
5661 && DECL_RTL (decl) != 0
5662 && (GET_CODE (DECL_RTL (decl)) == REG
5663 || (GET_CODE (DECL_RTL (decl)) == MEM
5664 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5666 /* If longjmp doesn't restore the registers,
5667 don't put anything in them. */
5668 #ifdef NON_SAVING_SETJMP
5672 ! DECL_REGISTER (decl)))
5673 put_var_into_stack (decl, /*rescan=*/true);
5676 /* Return the context-pointer register corresponding to DECL,
5677 or 0 if it does not need one. */
5680 lookup_static_chain (tree decl)
5682 tree context = decl_function_context (decl);
5686 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5689 /* We treat inline_function_decl as an alias for the current function
5690 because that is the inline function whose vars, types, etc.
5691 are being merged into the current function.
5692 See expand_inline_function. */
5693 if (context == current_function_decl || context == inline_function_decl)
5694 return virtual_stack_vars_rtx;
5696 for (link = context_display; link; link = TREE_CHAIN (link))
5697 if (TREE_PURPOSE (link) == context)
5698 return RTL_EXPR_RTL (TREE_VALUE (link));
5703 /* Convert a stack slot address ADDR for variable VAR
5704 (from a containing function)
5705 into an address valid in this function (using a static chain). */
5708 fix_lexical_addr (rtx addr, tree var)
5711 HOST_WIDE_INT displacement;
5712 tree context = decl_function_context (var);
5713 struct function *fp;
5716 /* If this is the present function, we need not do anything. */
5717 if (context == current_function_decl || context == inline_function_decl)
5720 fp = find_function_data (context);
5722 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5723 addr = XEXP (XEXP (addr, 0), 0);
5725 /* Decode given address as base reg plus displacement. */
5726 if (GET_CODE (addr) == REG)
5727 basereg = addr, displacement = 0;
5728 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5729 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5733 /* We accept vars reached via the containing function's
5734 incoming arg pointer and via its stack variables pointer. */
5735 if (basereg == fp->internal_arg_pointer)
5737 /* If reached via arg pointer, get the arg pointer value
5738 out of that function's stack frame.
5740 There are two cases: If a separate ap is needed, allocate a
5741 slot in the outer function for it and dereference it that way.
5742 This is correct even if the real ap is actually a pseudo.
5743 Otherwise, just adjust the offset from the frame pointer to
5746 #ifdef NEED_SEPARATE_AP
5749 addr = get_arg_pointer_save_area (fp);
5750 addr = fix_lexical_addr (XEXP (addr, 0), var);
5751 addr = memory_address (Pmode, addr);
5753 base = gen_rtx_MEM (Pmode, addr);
5754 set_mem_alias_set (base, get_frame_alias_set ());
5755 base = copy_to_reg (base);
5757 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5758 base = lookup_static_chain (var);
5762 else if (basereg == virtual_stack_vars_rtx)
5764 /* This is the same code as lookup_static_chain, duplicated here to
5765 avoid an extra call to decl_function_context. */
5768 for (link = context_display; link; link = TREE_CHAIN (link))
5769 if (TREE_PURPOSE (link) == context)
5771 base = RTL_EXPR_RTL (TREE_VALUE (link));
5779 /* Use same offset, relative to appropriate static chain or argument
5781 return plus_constant (base, displacement);
5784 /* Return the address of the trampoline for entering nested fn FUNCTION.
5785 If necessary, allocate a trampoline (in the stack frame)
5786 and emit rtl to initialize its contents (at entry to this function). */
5789 trampoline_address (tree function)
5794 struct function *fp;
5797 /* Find an existing trampoline and return it. */
5798 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5799 if (TREE_PURPOSE (link) == function)
5801 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5803 for (fp = outer_function_chain; fp; fp = fp->outer)
5804 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5805 if (TREE_PURPOSE (link) == function)
5807 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5809 return adjust_trampoline_addr (tramp);
5812 /* None exists; we must make one. */
5814 /* Find the `struct function' for the function containing FUNCTION. */
5816 fn_context = decl_function_context (function);
5817 if (fn_context != current_function_decl
5818 && fn_context != inline_function_decl)
5819 fp = find_function_data (fn_context);
5821 /* Allocate run-time space for this trampoline. */
5822 /* If rounding needed, allocate extra space
5823 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5824 #define TRAMPOLINE_REAL_SIZE \
5825 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5826 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5828 /* Record the trampoline for reuse and note it for later initialization
5829 by expand_function_end. */
5832 rtlexp = make_node (RTL_EXPR);
5833 RTL_EXPR_RTL (rtlexp) = tramp;
5834 fp->x_trampoline_list = tree_cons (function, rtlexp,
5835 fp->x_trampoline_list);
5839 /* Make the RTL_EXPR node temporary, not momentary, so that the
5840 trampoline_list doesn't become garbage. */
5841 rtlexp = make_node (RTL_EXPR);
5843 RTL_EXPR_RTL (rtlexp) = tramp;
5844 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5847 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5848 return adjust_trampoline_addr (tramp);
5851 /* Given a trampoline address,
5852 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5855 round_trampoline_addr (rtx tramp)
5857 /* Round address up to desired boundary. */
5858 rtx temp = gen_reg_rtx (Pmode);
5859 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5860 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5862 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5863 temp, 0, OPTAB_LIB_WIDEN);
5864 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5865 temp, 0, OPTAB_LIB_WIDEN);
5870 /* Given a trampoline address, round it then apply any
5871 platform-specific adjustments so that the result can be used for a
5875 adjust_trampoline_addr (rtx tramp)
5877 tramp = round_trampoline_addr (tramp);
5878 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5879 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5884 /* Put all this function's BLOCK nodes including those that are chained
5885 onto the first block into a vector, and return it.
5886 Also store in each NOTE for the beginning or end of a block
5887 the index of that block in the vector.
5888 The arguments are BLOCK, the chain of top-level blocks of the function,
5889 and INSNS, the insn chain of the function. */
5892 identify_blocks (void)
5895 tree *block_vector, *last_block_vector;
5897 tree block = DECL_INITIAL (current_function_decl);
5902 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5903 depth-first order. */
5904 block_vector = get_block_vector (block, &n_blocks);
5905 block_stack = xmalloc (n_blocks * sizeof (tree));
5907 last_block_vector = identify_blocks_1 (get_insns (),
5909 block_vector + n_blocks,
5912 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5913 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5914 if (0 && last_block_vector != block_vector + n_blocks)
5917 free (block_vector);
5921 /* Subroutine of identify_blocks. Do the block substitution on the
5922 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5924 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5925 BLOCK_VECTOR is incremented for each block seen. */
5928 identify_blocks_1 (rtx insns, tree *block_vector, tree *end_block_vector,
5929 tree *orig_block_stack)
5932 tree *block_stack = orig_block_stack;
5934 for (insn = insns; insn; insn = NEXT_INSN (insn))
5936 if (GET_CODE (insn) == NOTE)
5938 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5942 /* If there are more block notes than BLOCKs, something
5944 if (block_vector == end_block_vector)
5947 b = *block_vector++;
5948 NOTE_BLOCK (insn) = b;
5951 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5953 /* If there are more NOTE_INSN_BLOCK_ENDs than
5954 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5955 if (block_stack == orig_block_stack)
5958 NOTE_BLOCK (insn) = *--block_stack;
5961 else if (GET_CODE (insn) == CALL_INSN
5962 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5964 rtx cp = PATTERN (insn);
5966 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5967 end_block_vector, block_stack);
5969 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5970 end_block_vector, block_stack);
5972 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5973 end_block_vector, block_stack);
5977 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5978 something is badly wrong. */
5979 if (block_stack != orig_block_stack)
5982 return block_vector;
5985 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5986 and create duplicate blocks. */
5987 /* ??? Need an option to either create block fragments or to create
5988 abstract origin duplicates of a source block. It really depends
5989 on what optimization has been performed. */
5992 reorder_blocks (void)
5994 tree block = DECL_INITIAL (current_function_decl);
5995 varray_type block_stack;
5997 if (block == NULL_TREE)
6000 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
6002 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
6003 reorder_blocks_0 (block);
6005 /* Prune the old trees away, so that they don't get in the way. */
6006 BLOCK_SUBBLOCKS (block) = NULL_TREE;
6007 BLOCK_CHAIN (block) = NULL_TREE;
6009 /* Recreate the block tree from the note nesting. */
6010 reorder_blocks_1 (get_insns (), block, &block_stack);
6011 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
6013 /* Remove deleted blocks from the block fragment chains. */
6014 reorder_fix_fragments (block);
6017 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
6020 reorder_blocks_0 (tree block)
6024 TREE_ASM_WRITTEN (block) = 0;
6025 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
6026 block = BLOCK_CHAIN (block);
6031 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack)
6035 for (insn = insns; insn; insn = NEXT_INSN (insn))
6037 if (GET_CODE (insn) == NOTE)
6039 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6041 tree block = NOTE_BLOCK (insn);
6043 /* If we have seen this block before, that means it now
6044 spans multiple address regions. Create a new fragment. */
6045 if (TREE_ASM_WRITTEN (block))
6047 tree new_block = copy_node (block);
6050 origin = (BLOCK_FRAGMENT_ORIGIN (block)
6051 ? BLOCK_FRAGMENT_ORIGIN (block)
6053 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
6054 BLOCK_FRAGMENT_CHAIN (new_block)
6055 = BLOCK_FRAGMENT_CHAIN (origin);
6056 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
6058 NOTE_BLOCK (insn) = new_block;
6062 BLOCK_SUBBLOCKS (block) = 0;
6063 TREE_ASM_WRITTEN (block) = 1;
6064 /* When there's only one block for the entire function,
6065 current_block == block and we mustn't do this, it
6066 will cause infinite recursion. */
6067 if (block != current_block)
6069 BLOCK_SUPERCONTEXT (block) = current_block;
6070 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6071 BLOCK_SUBBLOCKS (current_block) = block;
6072 current_block = block;
6074 VARRAY_PUSH_TREE (*p_block_stack, block);
6076 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6078 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6079 VARRAY_POP (*p_block_stack);
6080 BLOCK_SUBBLOCKS (current_block)
6081 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6082 current_block = BLOCK_SUPERCONTEXT (current_block);
6085 else if (GET_CODE (insn) == CALL_INSN
6086 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6088 rtx cp = PATTERN (insn);
6089 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
6091 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6093 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6098 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6099 appears in the block tree, select one of the fragments to become
6100 the new origin block. */
6103 reorder_fix_fragments (tree block)
6107 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6108 tree new_origin = NULL_TREE;
6112 if (! TREE_ASM_WRITTEN (dup_origin))
6114 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6116 /* Find the first of the remaining fragments. There must
6117 be at least one -- the current block. */
6118 while (! TREE_ASM_WRITTEN (new_origin))
6119 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6120 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6123 else if (! dup_origin)
6126 /* Re-root the rest of the fragments to the new origin. In the
6127 case that DUP_ORIGIN was null, that means BLOCK was the origin
6128 of a chain of fragments and we want to remove those fragments
6129 that didn't make it to the output. */
6132 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6137 if (TREE_ASM_WRITTEN (chain))
6139 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6141 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6143 chain = BLOCK_FRAGMENT_CHAIN (chain);
6148 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6149 block = BLOCK_CHAIN (block);
6153 /* Reverse the order of elements in the chain T of blocks,
6154 and return the new head of the chain (old last element). */
6157 blocks_nreverse (tree t)
6159 tree prev = 0, decl, next;
6160 for (decl = t; decl; decl = next)
6162 next = BLOCK_CHAIN (decl);
6163 BLOCK_CHAIN (decl) = prev;
6169 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6170 non-NULL, list them all into VECTOR, in a depth-first preorder
6171 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6175 all_blocks (tree block, tree *vector)
6181 TREE_ASM_WRITTEN (block) = 0;
6183 /* Record this block. */
6185 vector[n_blocks] = block;
6189 /* Record the subblocks, and their subblocks... */
6190 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6191 vector ? vector + n_blocks : 0);
6192 block = BLOCK_CHAIN (block);
6198 /* Return a vector containing all the blocks rooted at BLOCK. The
6199 number of elements in the vector is stored in N_BLOCKS_P. The
6200 vector is dynamically allocated; it is the caller's responsibility
6201 to call `free' on the pointer returned. */
6204 get_block_vector (tree block, int *n_blocks_p)
6208 *n_blocks_p = all_blocks (block, NULL);
6209 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
6210 all_blocks (block, block_vector);
6212 return block_vector;
6215 static GTY(()) int next_block_index = 2;
6217 /* Set BLOCK_NUMBER for all the blocks in FN. */
6220 number_blocks (tree fn)
6226 /* For SDB and XCOFF debugging output, we start numbering the blocks
6227 from 1 within each function, rather than keeping a running
6229 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6230 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6231 next_block_index = 1;
6234 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6236 /* The top-level BLOCK isn't numbered at all. */
6237 for (i = 1; i < n_blocks; ++i)
6238 /* We number the blocks from two. */
6239 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6241 free (block_vector);
6246 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6249 debug_find_var_in_block_tree (tree var, tree block)
6253 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6257 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6259 tree ret = debug_find_var_in_block_tree (var, t);
6267 /* Allocate a function structure for FNDECL and set its contents
6271 allocate_struct_function (tree fndecl)
6275 cfun = ggc_alloc_cleared (sizeof (struct function));
6277 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6279 cfun->stack_alignment_needed = STACK_BOUNDARY;
6280 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6282 current_function_funcdef_no = funcdef_no++;
6284 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6286 init_stmt_for_function ();
6287 init_eh_for_function ();
6290 init_varasm_status (cfun);
6292 (*lang_hooks.function.init) (cfun);
6293 if (init_machine_status)
6294 cfun->machine = (*init_machine_status) ();
6299 DECL_SAVED_INSNS (fndecl) = cfun;
6300 cfun->decl = fndecl;
6302 current_function_name = (*lang_hooks.decl_printable_name) (fndecl, 2);
6304 result = DECL_RESULT (fndecl);
6305 if (aggregate_value_p (result, fndecl))
6307 #ifdef PCC_STATIC_STRUCT_RETURN
6308 current_function_returns_pcc_struct = 1;
6310 current_function_returns_struct = 1;
6313 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
6315 current_function_needs_context
6316 = (decl_function_context (current_function_decl) != 0
6317 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6320 /* Reset cfun, and other non-struct-function variables to defaults as
6321 appropriate for emiiting rtl at the start of a function. */
6324 prepare_function_start (tree fndecl)
6326 if (fndecl && DECL_SAVED_INSNS (fndecl))
6327 cfun = DECL_SAVED_INSNS (fndecl);
6329 allocate_struct_function (fndecl);
6331 cse_not_expected = ! optimize;
6333 /* Caller save not needed yet. */
6334 caller_save_needed = 0;
6336 /* We haven't done register allocation yet. */
6339 /* Indicate that we need to distinguish between the return value of the
6340 present function and the return value of a function being called. */
6341 rtx_equal_function_value_matters = 1;
6343 /* Indicate that we have not instantiated virtual registers yet. */
6344 virtuals_instantiated = 0;
6346 /* Indicate that we want CONCATs now. */
6347 generating_concat_p = 1;
6349 /* Indicate we have no need of a frame pointer yet. */
6350 frame_pointer_needed = 0;
6353 /* Initialize the rtl expansion mechanism so that we can do simple things
6354 like generate sequences. This is used to provide a context during global
6355 initialization of some passes. */
6357 init_dummy_function_start (void)
6359 prepare_function_start (NULL);
6362 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6363 and initialize static variables for generating RTL for the statements
6367 init_function_start (tree subr)
6369 prepare_function_start (subr);
6371 /* Within function body, compute a type's size as soon it is laid out. */
6372 immediate_size_expand++;
6374 /* Prevent ever trying to delete the first instruction of a
6375 function. Also tell final how to output a linenum before the
6376 function prologue. Note linenums could be missing, e.g. when
6377 compiling a Java .class file. */
6378 if (DECL_SOURCE_LINE (subr))
6379 emit_line_note (DECL_SOURCE_LOCATION (subr));
6381 /* Make sure first insn is a note even if we don't want linenums.
6382 This makes sure the first insn will never be deleted.
6383 Also, final expects a note to appear there. */
6384 emit_note (NOTE_INSN_DELETED);
6386 /* Warn if this value is an aggregate type,
6387 regardless of which calling convention we are using for it. */
6388 if (warn_aggregate_return
6389 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6390 warning ("function returns an aggregate");
6393 /* Make sure all values used by the optimization passes have sane
6396 init_function_for_compilation (void)
6400 /* No prologue/epilogue insns yet. */
6401 VARRAY_GROW (prologue, 0);
6402 VARRAY_GROW (epilogue, 0);
6403 VARRAY_GROW (sibcall_epilogue, 0);
6406 /* Expand a call to __main at the beginning of a possible main function. */
6408 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6409 #undef HAS_INIT_SECTION
6410 #define HAS_INIT_SECTION
6414 expand_main_function (void)
6416 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6417 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6419 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6423 /* Forcibly align the stack. */
6424 #ifdef STACK_GROWS_DOWNWARD
6425 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6426 stack_pointer_rtx, 1, OPTAB_WIDEN);
6428 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6429 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6430 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6431 stack_pointer_rtx, 1, OPTAB_WIDEN);
6433 if (tmp != stack_pointer_rtx)
6434 emit_move_insn (stack_pointer_rtx, tmp);
6436 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6437 tmp = force_reg (Pmode, const0_rtx);
6438 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6442 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6443 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6446 emit_insn_before (seq, tmp);
6452 #ifndef HAS_INIT_SECTION
6453 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6457 /* The PENDING_SIZES represent the sizes of variable-sized types.
6458 Create RTL for the various sizes now (using temporary variables),
6459 so that we can refer to the sizes from the RTL we are generating
6460 for the current function. The PENDING_SIZES are a TREE_LIST. The
6461 TREE_VALUE of each node is a SAVE_EXPR. */
6464 expand_pending_sizes (tree pending_sizes)
6468 /* Evaluate now the sizes of any types declared among the arguments. */
6469 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6471 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6472 /* Flush the queue in case this parameter declaration has
6478 /* Start the RTL for a new function, and set variables used for
6480 SUBR is the FUNCTION_DECL node.
6481 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6482 the function's parameters, which must be run at any return statement. */
6485 expand_function_start (tree subr, int parms_have_cleanups)
6488 rtx last_ptr = NULL_RTX;
6490 /* Make sure volatile mem refs aren't considered
6491 valid operands of arithmetic insns. */
6492 init_recog_no_volatile ();
6494 current_function_instrument_entry_exit
6495 = (flag_instrument_function_entry_exit
6496 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6498 current_function_profile
6500 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6502 current_function_limit_stack
6503 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6505 /* If function gets a static chain arg, store it in the stack frame.
6506 Do this first, so it gets the first stack slot offset. */
6507 if (current_function_needs_context)
6509 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6511 /* Delay copying static chain if it is not a register to avoid
6512 conflicts with regs used for parameters. */
6513 if (! SMALL_REGISTER_CLASSES
6514 || GET_CODE (static_chain_incoming_rtx) == REG)
6515 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6518 /* If the parameters of this function need cleaning up, get a label
6519 for the beginning of the code which executes those cleanups. This must
6520 be done before doing anything with return_label. */
6521 if (parms_have_cleanups)
6522 cleanup_label = gen_label_rtx ();
6526 /* Make the label for return statements to jump to. Do not special
6527 case machines with special return instructions -- they will be
6528 handled later during jump, ifcvt, or epilogue creation. */
6529 return_label = gen_label_rtx ();
6531 /* Initialize rtx used to return the value. */
6532 /* Do this before assign_parms so that we copy the struct value address
6533 before any library calls that assign parms might generate. */
6535 /* Decide whether to return the value in memory or in a register. */
6536 if (aggregate_value_p (DECL_RESULT (subr), subr))
6538 /* Returning something that won't go in a register. */
6539 rtx value_address = 0;
6541 #ifdef PCC_STATIC_STRUCT_RETURN
6542 if (current_function_returns_pcc_struct)
6544 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6545 value_address = assemble_static_space (size);
6550 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
6551 /* Expect to be passed the address of a place to store the value.
6552 If it is passed as an argument, assign_parms will take care of
6556 value_address = gen_reg_rtx (Pmode);
6557 emit_move_insn (value_address, sv);
6562 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6563 set_mem_attributes (x, DECL_RESULT (subr), 1);
6564 SET_DECL_RTL (DECL_RESULT (subr), x);
6567 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6568 /* If return mode is void, this decl rtl should not be used. */
6569 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6572 /* Compute the return values into a pseudo reg, which we will copy
6573 into the true return register after the cleanups are done. */
6575 /* In order to figure out what mode to use for the pseudo, we
6576 figure out what the mode of the eventual return register will
6577 actually be, and use that. */
6579 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6582 /* Structures that are returned in registers are not aggregate_value_p,
6583 so we may see a PARALLEL or a REG. */
6584 if (REG_P (hard_reg))
6585 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6586 else if (GET_CODE (hard_reg) == PARALLEL)
6587 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6591 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6592 result to the real return register(s). */
6593 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6596 /* Initialize rtx for parameters and local variables.
6597 In some cases this requires emitting insns. */
6599 assign_parms (subr);
6601 /* Copy the static chain now if it wasn't a register. The delay is to
6602 avoid conflicts with the parameter passing registers. */
6604 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6605 if (GET_CODE (static_chain_incoming_rtx) != REG)
6606 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6608 /* The following was moved from init_function_start.
6609 The move is supposed to make sdb output more accurate. */
6610 /* Indicate the beginning of the function body,
6611 as opposed to parm setup. */
6612 emit_note (NOTE_INSN_FUNCTION_BEG);
6614 if (GET_CODE (get_last_insn ()) != NOTE)
6615 emit_note (NOTE_INSN_DELETED);
6616 parm_birth_insn = get_last_insn ();
6618 context_display = 0;
6619 if (current_function_needs_context)
6621 /* Fetch static chain values for containing functions. */
6622 tem = decl_function_context (current_function_decl);
6623 /* Copy the static chain pointer into a pseudo. If we have
6624 small register classes, copy the value from memory if
6625 static_chain_incoming_rtx is a REG. */
6628 /* If the static chain originally came in a register, put it back
6629 there, then move it out in the next insn. The reason for
6630 this peculiar code is to satisfy function integration. */
6631 if (SMALL_REGISTER_CLASSES
6632 && GET_CODE (static_chain_incoming_rtx) == REG)
6633 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6634 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6639 tree rtlexp = make_node (RTL_EXPR);
6641 RTL_EXPR_RTL (rtlexp) = last_ptr;
6642 context_display = tree_cons (tem, rtlexp, context_display);
6643 tem = decl_function_context (tem);
6646 /* Chain thru stack frames, assuming pointer to next lexical frame
6647 is found at the place we always store it. */
6648 #ifdef FRAME_GROWS_DOWNWARD
6649 last_ptr = plus_constant (last_ptr,
6650 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6652 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6653 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6654 last_ptr = copy_to_reg (last_ptr);
6656 /* If we are not optimizing, ensure that we know that this
6657 piece of context is live over the entire function. */
6659 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6664 if (current_function_instrument_entry_exit)
6666 rtx fun = DECL_RTL (current_function_decl);
6667 if (GET_CODE (fun) == MEM)
6668 fun = XEXP (fun, 0);
6671 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6673 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6675 hard_frame_pointer_rtx),
6679 if (current_function_profile)
6682 PROFILE_HOOK (current_function_funcdef_no);
6686 /* After the display initializations is where the tail-recursion label
6687 should go, if we end up needing one. Ensure we have a NOTE here
6688 since some things (like trampolines) get placed before this. */
6689 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
6691 /* Evaluate now the sizes of any types declared among the arguments. */
6692 expand_pending_sizes (nreverse (get_pending_sizes ()));
6694 /* Make sure there is a line number after the function entry setup code. */
6695 force_next_line_note ();
6698 /* Undo the effects of init_dummy_function_start. */
6700 expand_dummy_function_end (void)
6702 /* End any sequences that failed to be closed due to syntax errors. */
6703 while (in_sequence_p ())
6706 /* Outside function body, can't compute type's actual size
6707 until next function's body starts. */
6709 free_after_parsing (cfun);
6710 free_after_compilation (cfun);
6714 /* Call DOIT for each hard register used as a return value from
6715 the current function. */
6718 diddle_return_value (void (*doit) (rtx, void *), void *arg)
6720 rtx outgoing = current_function_return_rtx;
6725 if (GET_CODE (outgoing) == REG)
6726 (*doit) (outgoing, arg);
6727 else if (GET_CODE (outgoing) == PARALLEL)
6731 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6733 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6735 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6742 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6744 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6748 clobber_return_register (void)
6750 diddle_return_value (do_clobber_return_reg, NULL);
6752 /* In case we do use pseudo to return value, clobber it too. */
6753 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6755 tree decl_result = DECL_RESULT (current_function_decl);
6756 rtx decl_rtl = DECL_RTL (decl_result);
6757 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6759 do_clobber_return_reg (decl_rtl, NULL);
6765 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6767 emit_insn (gen_rtx_USE (VOIDmode, reg));
6771 use_return_register (void)
6773 diddle_return_value (do_use_return_reg, NULL);
6776 static GTY(()) rtx initial_trampoline;
6778 /* Generate RTL for the end of the current function. */
6781 expand_function_end (void)
6786 finish_expr_for_function ();
6788 /* If arg_pointer_save_area was referenced only from a nested
6789 function, we will not have initialized it yet. Do that now. */
6790 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6791 get_arg_pointer_save_area (cfun);
6793 #ifdef NON_SAVING_SETJMP
6794 /* Don't put any variables in registers if we call setjmp
6795 on a machine that fails to restore the registers. */
6796 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6798 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6799 setjmp_protect (DECL_INITIAL (current_function_decl));
6801 setjmp_protect_args ();
6805 /* Initialize any trampolines required by this function. */
6806 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6808 tree function = TREE_PURPOSE (link);
6809 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6810 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6811 #ifdef TRAMPOLINE_TEMPLATE
6816 #ifdef TRAMPOLINE_TEMPLATE
6817 /* First make sure this compilation has a template for
6818 initializing trampolines. */
6819 if (initial_trampoline == 0)
6822 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6823 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6827 /* Generate insns to initialize the trampoline. */
6829 tramp = round_trampoline_addr (XEXP (tramp, 0));
6830 #ifdef TRAMPOLINE_TEMPLATE
6831 blktramp = replace_equiv_address (initial_trampoline, tramp);
6832 emit_block_move (blktramp, initial_trampoline,
6833 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6835 trampolines_created = 1;
6836 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6840 /* Put those insns at entry to the containing function (this one). */
6841 emit_insn_before (seq, tail_recursion_reentry);
6844 /* If we are doing stack checking and this function makes calls,
6845 do a stack probe at the start of the function to ensure we have enough
6846 space for another stack frame. */
6847 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6851 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6852 if (GET_CODE (insn) == CALL_INSN)
6855 probe_stack_range (STACK_CHECK_PROTECT,
6856 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6859 emit_insn_before (seq, tail_recursion_reentry);
6864 /* Possibly warn about unused parameters. */
6865 if (warn_unused_parameter)
6869 for (decl = DECL_ARGUMENTS (current_function_decl);
6870 decl; decl = TREE_CHAIN (decl))
6871 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6872 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6873 warning ("%Hunused parameter '%D'",
6874 &DECL_SOURCE_LOCATION (decl), decl);
6877 /* Delete handlers for nonlocal gotos if nothing uses them. */
6878 if (nonlocal_goto_handler_slots != 0
6879 && ! current_function_has_nonlocal_label)
6882 /* End any sequences that failed to be closed due to syntax errors. */
6883 while (in_sequence_p ())
6886 /* Outside function body, can't compute type's actual size
6887 until next function's body starts. */
6888 immediate_size_expand--;
6890 clear_pending_stack_adjust ();
6891 do_pending_stack_adjust ();
6893 /* Mark the end of the function body.
6894 If control reaches this insn, the function can drop through
6895 without returning a value. */
6896 emit_note (NOTE_INSN_FUNCTION_END);
6898 /* Must mark the last line number note in the function, so that the test
6899 coverage code can avoid counting the last line twice. This just tells
6900 the code to ignore the immediately following line note, since there
6901 already exists a copy of this note somewhere above. This line number
6902 note is still needed for debugging though, so we can't delete it. */
6903 if (flag_test_coverage)
6904 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
6906 /* Output a linenumber for the end of the function.
6907 SDB depends on this. */
6908 force_next_line_note ();
6909 emit_line_note (input_location);
6911 /* Before the return label (if any), clobber the return
6912 registers so that they are not propagated live to the rest of
6913 the function. This can only happen with functions that drop
6914 through; if there had been a return statement, there would
6915 have either been a return rtx, or a jump to the return label.
6917 We delay actual code generation after the current_function_value_rtx
6919 clobber_after = get_last_insn ();
6921 /* Output the label for the actual return from the function,
6922 if one is expected. This happens either because a function epilogue
6923 is used instead of a return instruction, or because a return was done
6924 with a goto in order to run local cleanups, or because of pcc-style
6925 structure returning. */
6927 emit_label (return_label);
6929 if (current_function_instrument_entry_exit)
6931 rtx fun = DECL_RTL (current_function_decl);
6932 if (GET_CODE (fun) == MEM)
6933 fun = XEXP (fun, 0);
6936 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6938 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6940 hard_frame_pointer_rtx),
6944 /* Let except.c know where it should emit the call to unregister
6945 the function context for sjlj exceptions. */
6946 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6947 sjlj_emit_function_exit_after (get_last_insn ());
6949 /* If we had calls to alloca, and this machine needs
6950 an accurate stack pointer to exit the function,
6951 insert some code to save and restore the stack pointer. */
6952 #ifdef EXIT_IGNORE_STACK
6953 if (! EXIT_IGNORE_STACK)
6955 if (current_function_calls_alloca)
6959 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6960 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6963 /* If scalar return value was computed in a pseudo-reg, or was a named
6964 return value that got dumped to the stack, copy that to the hard
6966 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6968 tree decl_result = DECL_RESULT (current_function_decl);
6969 rtx decl_rtl = DECL_RTL (decl_result);
6971 if (REG_P (decl_rtl)
6972 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6973 : DECL_REGISTER (decl_result))
6975 rtx real_decl_rtl = current_function_return_rtx;
6977 /* This should be set in assign_parms. */
6978 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
6981 /* If this is a BLKmode structure being returned in registers,
6982 then use the mode computed in expand_return. Note that if
6983 decl_rtl is memory, then its mode may have been changed,
6984 but that current_function_return_rtx has not. */
6985 if (GET_MODE (real_decl_rtl) == BLKmode)
6986 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
6988 /* If a named return value dumped decl_return to memory, then
6989 we may need to re-do the PROMOTE_MODE signed/unsigned
6991 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6993 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6995 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
6996 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6999 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7001 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7003 /* If expand_function_start has created a PARALLEL for decl_rtl,
7004 move the result to the real return registers. Otherwise, do
7005 a group load from decl_rtl for a named return. */
7006 if (GET_CODE (decl_rtl) == PARALLEL)
7007 emit_group_move (real_decl_rtl, decl_rtl);
7009 emit_group_load (real_decl_rtl, decl_rtl,
7010 TREE_TYPE (decl_result),
7011 int_size_in_bytes (TREE_TYPE (decl_result)));
7014 emit_move_insn (real_decl_rtl, decl_rtl);
7018 /* If returning a structure, arrange to return the address of the value
7019 in a place where debuggers expect to find it.
7021 If returning a structure PCC style,
7022 the caller also depends on this value.
7023 And current_function_returns_pcc_struct is not necessarily set. */
7024 if (current_function_returns_struct
7025 || current_function_returns_pcc_struct)
7028 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7029 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7030 #ifdef FUNCTION_OUTGOING_VALUE
7032 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7033 current_function_decl);
7036 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7039 /* Mark this as a function return value so integrate will delete the
7040 assignment and USE below when inlining this function. */
7041 REG_FUNCTION_VALUE_P (outgoing) = 1;
7043 #ifdef POINTERS_EXTEND_UNSIGNED
7044 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7045 if (GET_MODE (outgoing) != GET_MODE (value_address))
7046 value_address = convert_memory_address (GET_MODE (outgoing),
7050 emit_move_insn (outgoing, value_address);
7052 /* Show return register used to hold result (in this case the address
7054 current_function_return_rtx = outgoing;
7057 /* If this is an implementation of throw, do what's necessary to
7058 communicate between __builtin_eh_return and the epilogue. */
7059 expand_eh_return ();
7061 /* Emit the actual code to clobber return register. */
7066 clobber_return_register ();
7070 after = emit_insn_after (seq, clobber_after);
7072 if (clobber_after != after)
7073 cfun->x_clobber_return_insn = after;
7076 /* ??? This should no longer be necessary since stupid is no longer with
7077 us, but there are some parts of the compiler (eg reload_combine, and
7078 sh mach_dep_reorg) that still try and compute their own lifetime info
7079 instead of using the general framework. */
7080 use_return_register ();
7082 /* Fix up any gotos that jumped out to the outermost
7083 binding level of the function.
7084 Must follow emitting RETURN_LABEL. */
7086 /* If you have any cleanups to do at this point,
7087 and they need to create temporary variables,
7088 then you will lose. */
7089 expand_fixups (get_insns ());
7093 get_arg_pointer_save_area (struct function *f)
7095 rtx ret = f->x_arg_pointer_save_area;
7099 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7100 f->x_arg_pointer_save_area = ret;
7103 if (f == cfun && ! f->arg_pointer_save_area_init)
7107 /* Save the arg pointer at the beginning of the function. The
7108 generated stack slot may not be a valid memory address, so we
7109 have to check it and fix it if necessary. */
7111 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7115 push_topmost_sequence ();
7116 emit_insn_after (seq, get_insns ());
7117 pop_topmost_sequence ();
7123 /* Extend a vector that records the INSN_UIDs of INSNS
7124 (a list of one or more insns). */
7127 record_insns (rtx insns, varray_type *vecp)
7134 while (tmp != NULL_RTX)
7137 tmp = NEXT_INSN (tmp);
7140 i = VARRAY_SIZE (*vecp);
7141 VARRAY_GROW (*vecp, i + len);
7143 while (tmp != NULL_RTX)
7145 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7147 tmp = NEXT_INSN (tmp);
7151 /* Set the specified locator to the insn chain. */
7153 set_insn_locators (rtx insn, int loc)
7155 while (insn != NULL_RTX)
7158 INSN_LOCATOR (insn) = loc;
7159 insn = NEXT_INSN (insn);
7163 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7164 be running after reorg, SEQUENCE rtl is possible. */
7167 contains (rtx insn, varray_type vec)
7171 if (GET_CODE (insn) == INSN
7172 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7175 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7176 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7177 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7183 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7184 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7191 prologue_epilogue_contains (rtx insn)
7193 if (contains (insn, prologue))
7195 if (contains (insn, epilogue))
7201 sibcall_epilogue_contains (rtx insn)
7203 if (sibcall_epilogue)
7204 return contains (insn, sibcall_epilogue);
7209 /* Insert gen_return at the end of block BB. This also means updating
7210 block_for_insn appropriately. */
7213 emit_return_into_block (basic_block bb, rtx line_note)
7215 emit_jump_insn_after (gen_return (), bb->end);
7217 emit_note_copy_after (line_note, PREV_INSN (bb->end));
7219 #endif /* HAVE_return */
7221 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7223 /* These functions convert the epilogue into a variant that does not modify the
7224 stack pointer. This is used in cases where a function returns an object
7225 whose size is not known until it is computed. The called function leaves the
7226 object on the stack, leaves the stack depressed, and returns a pointer to
7229 What we need to do is track all modifications and references to the stack
7230 pointer, deleting the modifications and changing the references to point to
7231 the location the stack pointer would have pointed to had the modifications
7234 These functions need to be portable so we need to make as few assumptions
7235 about the epilogue as we can. However, the epilogue basically contains
7236 three things: instructions to reset the stack pointer, instructions to
7237 reload registers, possibly including the frame pointer, and an
7238 instruction to return to the caller.
7240 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7241 We also make no attempt to validate the insns we make since if they are
7242 invalid, we probably can't do anything valid. The intent is that these
7243 routines get "smarter" as more and more machines start to use them and
7244 they try operating on different epilogues.
7246 We use the following structure to track what the part of the epilogue that
7247 we've already processed has done. We keep two copies of the SP equivalence,
7248 one for use during the insn we are processing and one for use in the next
7249 insn. The difference is because one part of a PARALLEL may adjust SP
7250 and the other may use it. */
7254 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7255 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7256 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7257 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7258 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7259 should be set to once we no longer need
7263 static void handle_epilogue_set (rtx, struct epi_info *);
7264 static void emit_equiv_load (struct epi_info *);
7266 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7267 no modifications to the stack pointer. Return the new list of insns. */
7270 keep_stack_depressed (rtx insns)
7273 struct epi_info info;
7276 /* If the epilogue is just a single instruction, it ust be OK as is. */
7278 if (NEXT_INSN (insns) == NULL_RTX)
7281 /* Otherwise, start a sequence, initialize the information we have, and
7282 process all the insns we were given. */
7285 info.sp_equiv_reg = stack_pointer_rtx;
7287 info.equiv_reg_src = 0;
7291 while (insn != NULL_RTX)
7293 next = NEXT_INSN (insn);
7302 /* If this insn references the register that SP is equivalent to and
7303 we have a pending load to that register, we must force out the load
7304 first and then indicate we no longer know what SP's equivalent is. */
7305 if (info.equiv_reg_src != 0
7306 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7308 emit_equiv_load (&info);
7309 info.sp_equiv_reg = 0;
7312 info.new_sp_equiv_reg = info.sp_equiv_reg;
7313 info.new_sp_offset = info.sp_offset;
7315 /* If this is a (RETURN) and the return address is on the stack,
7316 update the address and change to an indirect jump. */
7317 if (GET_CODE (PATTERN (insn)) == RETURN
7318 || (GET_CODE (PATTERN (insn)) == PARALLEL
7319 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7321 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7323 HOST_WIDE_INT offset = 0;
7324 rtx jump_insn, jump_set;
7326 /* If the return address is in a register, we can emit the insn
7327 unchanged. Otherwise, it must be a MEM and we see what the
7328 base register and offset are. In any case, we have to emit any
7329 pending load to the equivalent reg of SP, if any. */
7330 if (GET_CODE (retaddr) == REG)
7332 emit_equiv_load (&info);
7337 else if (GET_CODE (retaddr) == MEM
7338 && GET_CODE (XEXP (retaddr, 0)) == REG)
7339 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7340 else if (GET_CODE (retaddr) == MEM
7341 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7342 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7343 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7345 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7346 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7351 /* If the base of the location containing the return pointer
7352 is SP, we must update it with the replacement address. Otherwise,
7353 just build the necessary MEM. */
7354 retaddr = plus_constant (base, offset);
7355 if (base == stack_pointer_rtx)
7356 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7357 plus_constant (info.sp_equiv_reg,
7360 retaddr = gen_rtx_MEM (Pmode, retaddr);
7362 /* If there is a pending load to the equivalent register for SP
7363 and we reference that register, we must load our address into
7364 a scratch register and then do that load. */
7365 if (info.equiv_reg_src
7366 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7371 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7372 if (HARD_REGNO_MODE_OK (regno, Pmode)
7373 && !fixed_regs[regno]
7374 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7375 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7377 && !refers_to_regno_p (regno,
7378 regno + HARD_REGNO_NREGS (regno,
7380 info.equiv_reg_src, NULL))
7383 if (regno == FIRST_PSEUDO_REGISTER)
7386 reg = gen_rtx_REG (Pmode, regno);
7387 emit_move_insn (reg, retaddr);
7391 emit_equiv_load (&info);
7392 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7394 /* Show the SET in the above insn is a RETURN. */
7395 jump_set = single_set (jump_insn);
7399 SET_IS_RETURN_P (jump_set) = 1;
7402 /* If SP is not mentioned in the pattern and its equivalent register, if
7403 any, is not modified, just emit it. Otherwise, if neither is set,
7404 replace the reference to SP and emit the insn. If none of those are
7405 true, handle each SET individually. */
7406 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7407 && (info.sp_equiv_reg == stack_pointer_rtx
7408 || !reg_set_p (info.sp_equiv_reg, insn)))
7410 else if (! reg_set_p (stack_pointer_rtx, insn)
7411 && (info.sp_equiv_reg == stack_pointer_rtx
7412 || !reg_set_p (info.sp_equiv_reg, insn)))
7414 if (! validate_replace_rtx (stack_pointer_rtx,
7415 plus_constant (info.sp_equiv_reg,
7422 else if (GET_CODE (PATTERN (insn)) == SET)
7423 handle_epilogue_set (PATTERN (insn), &info);
7424 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7426 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7427 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7428 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7433 info.sp_equiv_reg = info.new_sp_equiv_reg;
7434 info.sp_offset = info.new_sp_offset;
7439 insns = get_insns ();
7444 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7445 structure that contains information about what we've seen so far. We
7446 process this SET by either updating that data or by emitting one or
7450 handle_epilogue_set (rtx set, struct epi_info *p)
7452 /* First handle the case where we are setting SP. Record what it is being
7453 set from. If unknown, abort. */
7454 if (reg_set_p (stack_pointer_rtx, set))
7456 if (SET_DEST (set) != stack_pointer_rtx)
7459 if (GET_CODE (SET_SRC (set)) == PLUS
7460 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7462 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7463 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7466 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7468 /* If we are adjusting SP, we adjust from the old data. */
7469 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7471 p->new_sp_equiv_reg = p->sp_equiv_reg;
7472 p->new_sp_offset += p->sp_offset;
7475 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7481 /* Next handle the case where we are setting SP's equivalent register.
7482 If we already have a value to set it to, abort. We could update, but
7483 there seems little point in handling that case. Note that we have
7484 to allow for the case where we are setting the register set in
7485 the previous part of a PARALLEL inside a single insn. But use the
7486 old offset for any updates within this insn. */
7487 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7489 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7490 || p->equiv_reg_src != 0)
7494 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7495 plus_constant (p->sp_equiv_reg,
7499 /* Otherwise, replace any references to SP in the insn to its new value
7500 and emit the insn. */
7503 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7504 plus_constant (p->sp_equiv_reg,
7506 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7507 plus_constant (p->sp_equiv_reg,
7513 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7516 emit_equiv_load (struct epi_info *p)
7518 if (p->equiv_reg_src != 0)
7519 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7521 p->equiv_reg_src = 0;
7525 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7526 this into place with notes indicating where the prologue ends and where
7527 the epilogue begins. Update the basic block information when possible. */
7530 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
7534 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7537 #ifdef HAVE_prologue
7538 rtx prologue_end = NULL_RTX;
7540 #if defined (HAVE_epilogue) || defined(HAVE_return)
7541 rtx epilogue_end = NULL_RTX;
7544 #ifdef HAVE_prologue
7548 seq = gen_prologue ();
7551 /* Retain a map of the prologue insns. */
7552 record_insns (seq, &prologue);
7553 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
7557 set_insn_locators (seq, prologue_locator);
7559 /* Can't deal with multiple successors of the entry block
7560 at the moment. Function should always have at least one
7562 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7565 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7570 /* If the exit block has no non-fake predecessors, we don't need
7572 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7573 if ((e->flags & EDGE_FAKE) == 0)
7579 if (optimize && HAVE_return)
7581 /* If we're allowed to generate a simple return instruction,
7582 then by definition we don't need a full epilogue. Examine
7583 the block that falls through to EXIT. If it does not
7584 contain any code, examine its predecessors and try to
7585 emit (conditional) return instructions. */
7591 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7592 if (e->flags & EDGE_FALLTHRU)
7598 /* Verify that there are no active instructions in the last block. */
7600 while (label && GET_CODE (label) != CODE_LABEL)
7602 if (active_insn_p (label))
7604 label = PREV_INSN (label);
7607 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7609 rtx epilogue_line_note = NULL_RTX;
7611 /* Locate the line number associated with the closing brace,
7612 if we can find one. */
7613 for (seq = get_last_insn ();
7614 seq && ! active_insn_p (seq);
7615 seq = PREV_INSN (seq))
7616 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7618 epilogue_line_note = seq;
7622 for (e = last->pred; e; e = e_next)
7624 basic_block bb = e->src;
7627 e_next = e->pred_next;
7628 if (bb == ENTRY_BLOCK_PTR)
7632 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7635 /* If we have an unconditional jump, we can replace that
7636 with a simple return instruction. */
7637 if (simplejump_p (jump))
7639 emit_return_into_block (bb, epilogue_line_note);
7643 /* If we have a conditional jump, we can try to replace
7644 that with a conditional return instruction. */
7645 else if (condjump_p (jump))
7647 if (! redirect_jump (jump, 0, 0))
7650 /* If this block has only one successor, it both jumps
7651 and falls through to the fallthru block, so we can't
7653 if (bb->succ->succ_next == NULL)
7659 /* Fix up the CFG for the successful change we just made. */
7660 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7663 /* Emit a return insn for the exit fallthru block. Whether
7664 this is still reachable will be determined later. */
7666 emit_barrier_after (last->end);
7667 emit_return_into_block (last, epilogue_line_note);
7668 epilogue_end = last->end;
7669 last->succ->flags &= ~EDGE_FALLTHRU;
7674 #ifdef HAVE_epilogue
7677 /* Find the edge that falls through to EXIT. Other edges may exist
7678 due to RETURN instructions, but those don't need epilogues.
7679 There really shouldn't be a mixture -- either all should have
7680 been converted or none, however... */
7682 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7683 if (e->flags & EDGE_FALLTHRU)
7689 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
7691 seq = gen_epilogue ();
7693 #ifdef INCOMING_RETURN_ADDR_RTX
7694 /* If this function returns with the stack depressed and we can support
7695 it, massage the epilogue to actually do that. */
7696 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7697 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7698 seq = keep_stack_depressed (seq);
7701 emit_jump_insn (seq);
7703 /* Retain a map of the epilogue insns. */
7704 record_insns (seq, &epilogue);
7705 set_insn_locators (seq, epilogue_locator);
7710 insert_insn_on_edge (seq, e);
7717 commit_edge_insertions ();
7719 #ifdef HAVE_sibcall_epilogue
7720 /* Emit sibling epilogues before any sibling call sites. */
7721 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7723 basic_block bb = e->src;
7728 if (GET_CODE (insn) != CALL_INSN
7729 || ! SIBLING_CALL_P (insn))
7733 emit_insn (gen_sibcall_epilogue ());
7737 /* Retain a map of the epilogue insns. Used in life analysis to
7738 avoid getting rid of sibcall epilogue insns. Do this before we
7739 actually emit the sequence. */
7740 record_insns (seq, &sibcall_epilogue);
7741 set_insn_locators (seq, epilogue_locator);
7743 i = PREV_INSN (insn);
7744 newinsn = emit_insn_before (seq, insn);
7748 #ifdef HAVE_prologue
7753 /* GDB handles `break f' by setting a breakpoint on the first
7754 line note after the prologue. Which means (1) that if
7755 there are line number notes before where we inserted the
7756 prologue we should move them, and (2) we should generate a
7757 note before the end of the first basic block, if there isn't
7760 ??? This behavior is completely broken when dealing with
7761 multiple entry functions. We simply place the note always
7762 into first basic block and let alternate entry points
7766 for (insn = prologue_end; insn; insn = prev)
7768 prev = PREV_INSN (insn);
7769 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7771 /* Note that we cannot reorder the first insn in the
7772 chain, since rest_of_compilation relies on that
7773 remaining constant. */
7776 reorder_insns (insn, insn, prologue_end);
7780 /* Find the last line number note in the first block. */
7781 for (insn = ENTRY_BLOCK_PTR->next_bb->end;
7782 insn != prologue_end && insn;
7783 insn = PREV_INSN (insn))
7784 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7787 /* If we didn't find one, make a copy of the first line number
7791 for (insn = next_active_insn (prologue_end);
7793 insn = PREV_INSN (insn))
7794 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7796 emit_note_copy_after (insn, prologue_end);
7802 #ifdef HAVE_epilogue
7807 /* Similarly, move any line notes that appear after the epilogue.
7808 There is no need, however, to be quite so anal about the existence
7810 for (insn = epilogue_end; insn; insn = next)
7812 next = NEXT_INSN (insn);
7813 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7814 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7820 /* Reposition the prologue-end and epilogue-begin notes after instruction
7821 scheduling and delayed branch scheduling. */
7824 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
7826 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7827 rtx insn, last, note;
7830 if ((len = VARRAY_SIZE (prologue)) > 0)
7834 /* Scan from the beginning until we reach the last prologue insn.
7835 We apparently can't depend on basic_block_{head,end} after
7837 for (insn = f; insn; insn = NEXT_INSN (insn))
7839 if (GET_CODE (insn) == NOTE)
7841 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7844 else if (contains (insn, prologue))
7854 /* Find the prologue-end note if we haven't already, and
7855 move it to just after the last prologue insn. */
7858 for (note = last; (note = NEXT_INSN (note));)
7859 if (GET_CODE (note) == NOTE
7860 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7864 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7865 if (GET_CODE (last) == CODE_LABEL)
7866 last = NEXT_INSN (last);
7867 reorder_insns (note, note, last);
7871 if ((len = VARRAY_SIZE (epilogue)) > 0)
7875 /* Scan from the end until we reach the first epilogue insn.
7876 We apparently can't depend on basic_block_{head,end} after
7878 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7880 if (GET_CODE (insn) == NOTE)
7882 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7885 else if (contains (insn, epilogue))
7895 /* Find the epilogue-begin note if we haven't already, and
7896 move it to just before the first epilogue insn. */
7899 for (note = insn; (note = PREV_INSN (note));)
7900 if (GET_CODE (note) == NOTE
7901 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7905 if (PREV_INSN (last) != note)
7906 reorder_insns (note, note, PREV_INSN (last));
7909 #endif /* HAVE_prologue or HAVE_epilogue */
7912 /* Called once, at initialization, to initialize function.c. */
7915 init_function_once (void)
7917 VARRAY_INT_INIT (prologue, 0, "prologue");
7918 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7919 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
7922 #include "gt-function.h"