1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
43 #include "coretypes.h"
54 #include "hard-reg-set.h"
55 #include "insn-config.h"
58 #include "basic-block.h"
63 #include "integrate.h"
64 #include "langhooks.h"
67 #ifndef 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 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
81 /* Some systems use __main in a way incompatible with its use in gcc, in these
82 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
83 give the same symbol without quotes for an alternative entry point. You
84 must define both, or neither. */
86 #define NAME__MAIN "__main"
89 /* Round a value to the lowest integer less than it that is a multiple of
90 the required alignment. Avoid using division in case the value is
91 negative. Assume the alignment is a power of two. */
92 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
94 /* Similar, but round to the next highest integer that meets the
96 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
98 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
99 during rtl generation. If they are different register numbers, this is
100 always true. It may also be true if
101 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
102 generation. See fix_lexical_addr for details. */
104 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
105 #define NEED_SEPARATE_AP
108 /* Nonzero if function being compiled doesn't contain any calls
109 (ignoring the prologue and epilogue). This is set prior to
110 local register allocation and is valid for the remaining
112 int current_function_is_leaf;
114 /* Nonzero if function being compiled doesn't contain any instructions
115 that can throw an exception. This is set prior to final. */
117 int current_function_nothrow;
119 /* Nonzero if function being compiled doesn't modify the stack pointer
120 (ignoring the prologue and epilogue). This is only valid after
121 life_analysis has run. */
122 int current_function_sp_is_unchanging;
124 /* Nonzero if the function being compiled is a leaf function which only
125 uses leaf registers. This is valid after reload (specifically after
126 sched2) and is useful only if the port defines LEAF_REGISTERS. */
127 int current_function_uses_only_leaf_regs;
129 /* Nonzero once virtual register instantiation has been done.
130 assign_stack_local uses frame_pointer_rtx when this is nonzero.
131 calls.c:emit_library_call_value_1 uses it to set up
132 post-instantiation libcalls. */
133 int virtuals_instantiated;
135 /* Nonzero if at least one trampoline has been created. */
136 int trampolines_created;
138 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
139 static GTY(()) int funcdef_no;
141 /* These variables hold pointers to functions to create and destroy
142 target specific, per-function data structures. */
143 struct machine_function * (*init_machine_status) (void);
145 /* The FUNCTION_DECL for an inline function currently being expanded. */
146 tree inline_function_decl;
148 /* The currently compiled function. */
149 struct function *cfun = 0;
151 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
152 static GTY(()) varray_type prologue;
153 static GTY(()) varray_type epilogue;
155 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
157 static GTY(()) varray_type sibcall_epilogue;
159 /* In order to evaluate some expressions, such as function calls returning
160 structures in memory, we need to temporarily allocate stack locations.
161 We record each allocated temporary in the following structure.
163 Associated with each temporary slot is a nesting level. When we pop up
164 one level, all temporaries associated with the previous level are freed.
165 Normally, all temporaries are freed after the execution of the statement
166 in which they were created. However, if we are inside a ({...}) grouping,
167 the result may be in a temporary and hence must be preserved. If the
168 result could be in a temporary, we preserve it if we can determine which
169 one it is in. If we cannot determine which temporary may contain the
170 result, all temporaries are preserved. A temporary is preserved by
171 pretending it was allocated at the previous nesting level.
173 Automatic variables are also assigned temporary slots, at the nesting
174 level where they are defined. They are marked a "kept" so that
175 free_temp_slots will not free them. */
177 struct temp_slot GTY(())
179 /* Points to next temporary slot. */
180 struct temp_slot *next;
181 /* The rtx to used to reference the slot. */
183 /* The rtx used to represent the address if not the address of the
184 slot above. May be an EXPR_LIST if multiple addresses exist. */
186 /* The alignment (in bits) of the slot. */
188 /* The size, in units, of the slot. */
190 /* The type of the object in the slot, or zero if it doesn't correspond
191 to a type. We use this to determine whether a slot can be reused.
192 It can be reused if objects of the type of the new slot will always
193 conflict with objects of the type of the old slot. */
195 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
197 /* Nonzero if this temporary is currently in use. */
199 /* Nonzero if this temporary has its address taken. */
201 /* Nesting level at which this slot is being used. */
203 /* Nonzero if this should survive a call to free_temp_slots. */
205 /* The offset of the slot from the frame_pointer, including extra space
206 for alignment. This info is for combine_temp_slots. */
207 HOST_WIDE_INT base_offset;
208 /* The size of the slot, including extra space for alignment. This
209 info is for combine_temp_slots. */
210 HOST_WIDE_INT full_size;
213 /* This structure is used to record MEMs or pseudos used to replace VAR, any
214 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
215 maintain this list in case two operands of an insn were required to match;
216 in that case we must ensure we use the same replacement. */
218 struct fixup_replacement GTY(())
222 struct fixup_replacement *next;
225 struct insns_for_mem_entry
229 /* These are the INSNs which reference the MEM. */
233 /* Forward declarations. */
235 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int,
237 static struct temp_slot *find_temp_slot_from_address (rtx);
238 static void put_reg_into_stack (struct function *, rtx, tree, enum machine_mode,
239 enum machine_mode, int, unsigned int, int, htab_t);
240 static void schedule_fixup_var_refs (struct function *, rtx, tree, enum machine_mode,
242 static void fixup_var_refs (rtx, enum machine_mode, int, rtx, htab_t);
243 static struct fixup_replacement
244 *find_fixup_replacement (struct fixup_replacement **, rtx);
245 static void fixup_var_refs_insns (rtx, rtx, enum machine_mode, int, int, rtx);
246 static void fixup_var_refs_insns_with_hash (htab_t, rtx, enum machine_mode, int, rtx);
247 static void fixup_var_refs_insn (rtx, rtx, enum machine_mode, int, int, rtx);
248 static void fixup_var_refs_1 (rtx, enum machine_mode, rtx *, rtx,
249 struct fixup_replacement **, rtx);
250 static rtx fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
251 static rtx walk_fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
252 static rtx fixup_stack_1 (rtx, rtx);
253 static void optimize_bit_field (rtx, rtx, rtx *);
254 static void instantiate_decls (tree, int);
255 static void instantiate_decls_1 (tree, int);
256 static void instantiate_decl (rtx, HOST_WIDE_INT, int);
257 static rtx instantiate_new_reg (rtx, HOST_WIDE_INT *);
258 static int instantiate_virtual_regs_1 (rtx *, rtx, int);
259 static void delete_handlers (void);
260 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
261 static void pad_below (struct args_size *, enum machine_mode, tree);
262 static rtx round_trampoline_addr (rtx);
263 static rtx adjust_trampoline_addr (rtx);
264 static tree *identify_blocks_1 (rtx, tree *, tree *, tree *);
265 static void reorder_blocks_0 (tree);
266 static void reorder_blocks_1 (rtx, tree, varray_type *);
267 static void reorder_fix_fragments (tree);
268 static tree blocks_nreverse (tree);
269 static int all_blocks (tree, tree *);
270 static tree *get_block_vector (tree, int *);
271 extern tree debug_find_var_in_block_tree (tree, tree);
272 /* We always define `record_insns' even if it's not used so that we
273 can always export `prologue_epilogue_contains'. */
274 static void record_insns (rtx, varray_type *) ATTRIBUTE_UNUSED;
275 static int contains (rtx, varray_type);
277 static void emit_return_into_block (basic_block, rtx);
279 static void put_addressof_into_stack (rtx, htab_t);
280 static bool purge_addressof_1 (rtx *, rtx, int, int, int, htab_t);
281 static void purge_single_hard_subreg_set (rtx);
282 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
283 static rtx keep_stack_depressed (rtx);
285 static int is_addressof (rtx *, void *);
286 static hashval_t insns_for_mem_hash (const void *);
287 static int insns_for_mem_comp (const void *, const void *);
288 static int insns_for_mem_walk (rtx *, void *);
289 static void compute_insns_for_mem (rtx, rtx, htab_t);
290 static void prepare_function_start (tree);
291 static void do_clobber_return_reg (rtx, void *);
292 static void do_use_return_reg (rtx, void *);
293 static void instantiate_virtual_regs_lossage (rtx);
294 static tree split_complex_args (tree);
295 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
297 /* Pointer to chain of `struct function' for containing functions. */
298 struct function *outer_function_chain;
300 /* List of insns that were postponed by purge_addressof_1. */
301 static rtx postponed_insns;
303 /* Given a function decl for a containing function,
304 return the `struct function' for it. */
307 find_function_data (tree decl)
311 for (p = outer_function_chain; p; p = p->outer)
318 /* Save the current context for compilation of a nested function.
319 This is called from language-specific code. The caller should use
320 the enter_nested langhook to save any language-specific state,
321 since this function knows only about language-independent
325 push_function_context_to (tree context)
331 if (context == current_function_decl)
332 cfun->contains_functions = 1;
335 struct function *containing = find_function_data (context);
336 containing->contains_functions = 1;
341 init_dummy_function_start ();
344 p->outer = outer_function_chain;
345 outer_function_chain = p;
346 p->fixup_var_refs_queue = 0;
348 (*lang_hooks.function.enter_nested) (p);
354 push_function_context (void)
356 push_function_context_to (current_function_decl);
359 /* Restore the last saved context, at the end of a nested function.
360 This function is called from language-specific code. */
363 pop_function_context_from (tree context ATTRIBUTE_UNUSED)
365 struct function *p = outer_function_chain;
366 struct var_refs_queue *queue;
369 outer_function_chain = p->outer;
371 current_function_decl = p->decl;
374 restore_emit_status (p);
376 (*lang_hooks.function.leave_nested) (p);
378 /* Finish doing put_var_into_stack for any of our variables which became
379 addressable during the nested function. If only one entry has to be
380 fixed up, just do that one. Otherwise, first make a list of MEMs that
381 are not to be unshared. */
382 if (p->fixup_var_refs_queue == 0)
384 else if (p->fixup_var_refs_queue->next == 0)
385 fixup_var_refs (p->fixup_var_refs_queue->modified,
386 p->fixup_var_refs_queue->promoted_mode,
387 p->fixup_var_refs_queue->unsignedp,
388 p->fixup_var_refs_queue->modified, 0);
393 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
394 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
396 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
397 fixup_var_refs (queue->modified, queue->promoted_mode,
398 queue->unsignedp, list, 0);
402 p->fixup_var_refs_queue = 0;
404 /* Reset variables that have known state during rtx generation. */
405 rtx_equal_function_value_matters = 1;
406 virtuals_instantiated = 0;
407 generating_concat_p = 1;
411 pop_function_context (void)
413 pop_function_context_from (current_function_decl);
416 /* Clear out all parts of the state in F that can safely be discarded
417 after the function has been parsed, but not compiled, to let
418 garbage collection reclaim the memory. */
421 free_after_parsing (struct function *f)
423 /* f->expr->forced_labels is used by code generation. */
424 /* f->emit->regno_reg_rtx is used by code generation. */
425 /* f->varasm is used by code generation. */
426 /* f->eh->eh_return_stub_label is used by code generation. */
428 (*lang_hooks.function.final) (f);
432 /* Clear out all parts of the state in F that can safely be discarded
433 after the function has been compiled, to let garbage collection
434 reclaim the memory. */
437 free_after_compilation (struct function *f)
445 f->x_temp_slots = NULL;
446 f->arg_offset_rtx = NULL;
447 f->return_rtx = NULL;
448 f->internal_arg_pointer = NULL;
449 f->x_nonlocal_labels = NULL;
450 f->x_nonlocal_goto_handler_slots = NULL;
451 f->x_nonlocal_goto_handler_labels = NULL;
452 f->x_nonlocal_goto_stack_level = NULL;
453 f->x_cleanup_label = NULL;
454 f->x_return_label = NULL;
455 f->x_naked_return_label = NULL;
456 f->computed_goto_common_label = NULL;
457 f->computed_goto_common_reg = NULL;
458 f->x_save_expr_regs = NULL;
459 f->x_stack_slot_list = NULL;
460 f->x_rtl_expr_chain = NULL;
461 f->x_tail_recursion_label = NULL;
462 f->x_tail_recursion_reentry = NULL;
463 f->x_arg_pointer_save_area = NULL;
464 f->x_clobber_return_insn = NULL;
465 f->x_context_display = NULL;
466 f->x_trampoline_list = NULL;
467 f->x_parm_birth_insn = NULL;
468 f->x_last_parm_insn = NULL;
469 f->x_parm_reg_stack_loc = NULL;
470 f->fixup_var_refs_queue = NULL;
471 f->original_arg_vector = NULL;
472 f->original_decl_initial = NULL;
473 f->inl_last_parm_insn = NULL;
474 f->epilogue_delay_list = NULL;
477 /* Allocate fixed slots in the stack frame of the current function. */
479 /* Return size needed for stack frame based on slots so far allocated in
481 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
482 the caller may have to do that. */
485 get_func_frame_size (struct function *f)
487 #ifdef FRAME_GROWS_DOWNWARD
488 return -f->x_frame_offset;
490 return f->x_frame_offset;
494 /* Return size needed for stack frame based on slots so far allocated.
495 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
496 the caller may have to do that. */
498 get_frame_size (void)
500 return get_func_frame_size (cfun);
503 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
504 with machine mode MODE.
506 ALIGN controls the amount of alignment for the address of the slot:
507 0 means according to MODE,
508 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
509 positive specifies alignment boundary in bits.
511 We do not round to stack_boundary here.
513 FUNCTION specifies the function to allocate in. */
516 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
517 struct function *function)
520 int bigend_correction = 0;
522 int frame_off, frame_alignment, frame_phase;
529 alignment = BIGGEST_ALIGNMENT;
531 alignment = GET_MODE_ALIGNMENT (mode);
533 /* Allow the target to (possibly) increase the alignment of this
535 type = (*lang_hooks.types.type_for_mode) (mode, 0);
537 alignment = LOCAL_ALIGNMENT (type, alignment);
539 alignment /= BITS_PER_UNIT;
541 else if (align == -1)
543 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
544 size = CEIL_ROUND (size, alignment);
547 alignment = align / BITS_PER_UNIT;
549 #ifdef FRAME_GROWS_DOWNWARD
550 function->x_frame_offset -= size;
553 /* Ignore alignment we can't do with expected alignment of the boundary. */
554 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
555 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
557 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
558 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
560 /* Calculate how many bytes the start of local variables is off from
562 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
563 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
564 frame_phase = frame_off ? frame_alignment - frame_off : 0;
566 /* Round the frame offset to the specified alignment. The default is
567 to always honor requests to align the stack but a port may choose to
568 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
569 if (STACK_ALIGNMENT_NEEDED
573 /* We must be careful here, since FRAME_OFFSET might be negative and
574 division with a negative dividend isn't as well defined as we might
575 like. So we instead assume that ALIGNMENT is a power of two and
576 use logical operations which are unambiguous. */
577 #ifdef FRAME_GROWS_DOWNWARD
578 function->x_frame_offset
579 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
582 function->x_frame_offset
583 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
588 /* On a big-endian machine, if we are allocating more space than we will use,
589 use the least significant bytes of those that are allocated. */
590 if (BYTES_BIG_ENDIAN && mode != BLKmode)
591 bigend_correction = size - GET_MODE_SIZE (mode);
593 /* If we have already instantiated virtual registers, return the actual
594 address relative to the frame pointer. */
595 if (function == cfun && virtuals_instantiated)
596 addr = plus_constant (frame_pointer_rtx,
598 (frame_offset + bigend_correction
599 + STARTING_FRAME_OFFSET, Pmode));
601 addr = plus_constant (virtual_stack_vars_rtx,
603 (function->x_frame_offset + bigend_correction,
606 #ifndef FRAME_GROWS_DOWNWARD
607 function->x_frame_offset += size;
610 x = gen_rtx_MEM (mode, addr);
612 function->x_stack_slot_list
613 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
618 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
622 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
624 return assign_stack_local_1 (mode, size, align, cfun);
627 /* Allocate a temporary stack slot and record it for possible later
630 MODE is the machine mode to be given to the returned rtx.
632 SIZE is the size in units of the space required. We do no rounding here
633 since assign_stack_local will do any required rounding.
635 KEEP is 1 if this slot is to be retained after a call to
636 free_temp_slots. Automatic variables for a block are allocated
637 with this flag. KEEP is 2 if we allocate a longer term temporary,
638 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
639 if we are to allocate something at an inner level to be treated as
640 a variable in the block (e.g., a SAVE_EXPR).
642 TYPE is the type that will be used for the stack slot. */
645 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, int keep,
649 struct temp_slot *p, *best_p = 0;
652 /* If SIZE is -1 it means that somebody tried to allocate a temporary
653 of a variable size. */
658 align = BIGGEST_ALIGNMENT;
660 align = GET_MODE_ALIGNMENT (mode);
663 type = (*lang_hooks.types.type_for_mode) (mode, 0);
666 align = LOCAL_ALIGNMENT (type, align);
668 /* Try to find an available, already-allocated temporary of the proper
669 mode which meets the size and alignment requirements. Choose the
670 smallest one with the closest alignment. */
671 for (p = temp_slots; p; p = p->next)
672 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
674 && objects_must_conflict_p (p->type, type)
675 && (best_p == 0 || best_p->size > p->size
676 || (best_p->size == p->size && best_p->align > p->align)))
678 if (p->align == align && p->size == size)
686 /* Make our best, if any, the one to use. */
689 /* If there are enough aligned bytes left over, make them into a new
690 temp_slot so that the extra bytes don't get wasted. Do this only
691 for BLKmode slots, so that we can be sure of the alignment. */
692 if (GET_MODE (best_p->slot) == BLKmode)
694 int alignment = best_p->align / BITS_PER_UNIT;
695 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
697 if (best_p->size - rounded_size >= alignment)
699 p = ggc_alloc (sizeof (struct temp_slot));
700 p->in_use = p->addr_taken = 0;
701 p->size = best_p->size - rounded_size;
702 p->base_offset = best_p->base_offset + rounded_size;
703 p->full_size = best_p->full_size - rounded_size;
704 p->slot = gen_rtx_MEM (BLKmode,
705 plus_constant (XEXP (best_p->slot, 0),
707 p->align = best_p->align;
710 p->type = best_p->type;
711 p->next = temp_slots;
714 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
717 best_p->size = rounded_size;
718 best_p->full_size = rounded_size;
725 /* If we still didn't find one, make a new temporary. */
728 HOST_WIDE_INT frame_offset_old = frame_offset;
730 p = ggc_alloc (sizeof (struct temp_slot));
732 /* We are passing an explicit alignment request to assign_stack_local.
733 One side effect of that is assign_stack_local will not round SIZE
734 to ensure the frame offset remains suitably aligned.
736 So for requests which depended on the rounding of SIZE, we go ahead
737 and round it now. We also make sure ALIGNMENT is at least
738 BIGGEST_ALIGNMENT. */
739 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
741 p->slot = assign_stack_local (mode,
743 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
749 /* The following slot size computation is necessary because we don't
750 know the actual size of the temporary slot until assign_stack_local
751 has performed all the frame alignment and size rounding for the
752 requested temporary. Note that extra space added for alignment
753 can be either above or below this stack slot depending on which
754 way the frame grows. We include the extra space if and only if it
755 is above this slot. */
756 #ifdef FRAME_GROWS_DOWNWARD
757 p->size = frame_offset_old - frame_offset;
762 /* Now define the fields used by combine_temp_slots. */
763 #ifdef FRAME_GROWS_DOWNWARD
764 p->base_offset = frame_offset;
765 p->full_size = frame_offset_old - frame_offset;
767 p->base_offset = frame_offset_old;
768 p->full_size = frame_offset - frame_offset_old;
771 p->next = temp_slots;
777 p->rtl_expr = seq_rtl_expr;
782 p->level = target_temp_slot_level;
787 p->level = var_temp_slot_level;
792 p->level = temp_slot_level;
797 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
798 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
799 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
801 /* If we know the alias set for the memory that will be used, use
802 it. If there's no TYPE, then we don't know anything about the
803 alias set for the memory. */
804 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
805 set_mem_align (slot, align);
807 /* If a type is specified, set the relevant flags. */
810 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
811 && TYPE_READONLY (type));
812 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
813 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
819 /* Allocate a temporary stack slot and record it for possible later
820 reuse. First three arguments are same as in preceding function. */
823 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
825 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
828 /* Assign a temporary.
829 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
830 and so that should be used in error messages. In either case, we
831 allocate of the given type.
832 KEEP is as for assign_stack_temp.
833 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
834 it is 0 if a register is OK.
835 DONT_PROMOTE is 1 if we should not promote values in register
839 assign_temp (tree type_or_decl, int keep, int memory_required,
840 int dont_promote ATTRIBUTE_UNUSED)
843 enum machine_mode mode;
844 #ifndef PROMOTE_FOR_CALL_ONLY
848 if (DECL_P (type_or_decl))
849 decl = type_or_decl, type = TREE_TYPE (decl);
851 decl = NULL, type = type_or_decl;
853 mode = TYPE_MODE (type);
854 #ifndef PROMOTE_FOR_CALL_ONLY
855 unsignedp = TREE_UNSIGNED (type);
858 if (mode == BLKmode || memory_required)
860 HOST_WIDE_INT size = int_size_in_bytes (type);
863 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
864 problems with allocating the stack space. */
868 /* Unfortunately, we don't yet know how to allocate variable-sized
869 temporaries. However, sometimes we have a fixed upper limit on
870 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
871 instead. This is the case for Chill variable-sized strings. */
872 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
873 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
874 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
875 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
877 /* The size of the temporary may be too large to fit into an integer. */
878 /* ??? Not sure this should happen except for user silliness, so limit
879 this to things that aren't compiler-generated temporaries. The
880 rest of the time we'll abort in assign_stack_temp_for_type. */
881 if (decl && size == -1
882 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
884 error ("%Jsize of variable '%D' is too large", decl, decl);
888 tmp = assign_stack_temp_for_type (mode, size, keep, type);
892 #ifndef PROMOTE_FOR_CALL_ONLY
894 mode = promote_mode (type, mode, &unsignedp, 0);
897 return gen_reg_rtx (mode);
900 /* Combine temporary stack slots which are adjacent on the stack.
902 This allows for better use of already allocated stack space. This is only
903 done for BLKmode slots because we can be sure that we won't have alignment
904 problems in this case. */
907 combine_temp_slots (void)
909 struct temp_slot *p, *q;
910 struct temp_slot *prev_p, *prev_q;
913 /* We can't combine slots, because the information about which slot
914 is in which alias set will be lost. */
915 if (flag_strict_aliasing)
918 /* If there are a lot of temp slots, don't do anything unless
919 high levels of optimization. */
920 if (! flag_expensive_optimizations)
921 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
922 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
925 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
929 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
930 for (q = p->next, prev_q = p; q; q = prev_q->next)
933 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
935 if (p->base_offset + p->full_size == q->base_offset)
937 /* Q comes after P; combine Q into P. */
939 p->full_size += q->full_size;
942 else if (q->base_offset + q->full_size == p->base_offset)
944 /* P comes after Q; combine P into Q. */
946 q->full_size += p->full_size;
951 /* Either delete Q or advance past it. */
953 prev_q->next = q->next;
957 /* Either delete P or advance past it. */
961 prev_p->next = p->next;
963 temp_slots = p->next;
970 /* Find the temp slot corresponding to the object at address X. */
972 static struct temp_slot *
973 find_temp_slot_from_address (rtx x)
978 for (p = temp_slots; p; p = p->next)
983 else if (XEXP (p->slot, 0) == x
985 || (GET_CODE (x) == PLUS
986 && XEXP (x, 0) == virtual_stack_vars_rtx
987 && GET_CODE (XEXP (x, 1)) == CONST_INT
988 && INTVAL (XEXP (x, 1)) >= p->base_offset
989 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
992 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
993 for (next = p->address; next; next = XEXP (next, 1))
994 if (XEXP (next, 0) == x)
998 /* If we have a sum involving a register, see if it points to a temp
1000 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1001 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1003 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1004 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1010 /* Indicate that NEW is an alternate way of referring to the temp slot
1011 that previously was known by OLD. */
1014 update_temp_slot_address (rtx old, rtx new)
1016 struct temp_slot *p;
1018 if (rtx_equal_p (old, new))
1021 p = find_temp_slot_from_address (old);
1023 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1024 is a register, see if one operand of the PLUS is a temporary
1025 location. If so, NEW points into it. Otherwise, if both OLD and
1026 NEW are a PLUS and if there is a register in common between them.
1027 If so, try a recursive call on those values. */
1030 if (GET_CODE (old) != PLUS)
1033 if (GET_CODE (new) == REG)
1035 update_temp_slot_address (XEXP (old, 0), new);
1036 update_temp_slot_address (XEXP (old, 1), new);
1039 else if (GET_CODE (new) != PLUS)
1042 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1043 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1044 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1045 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1046 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1047 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1048 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1049 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1054 /* Otherwise add an alias for the temp's address. */
1055 else if (p->address == 0)
1059 if (GET_CODE (p->address) != EXPR_LIST)
1060 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1062 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1066 /* If X could be a reference to a temporary slot, mark the fact that its
1067 address was taken. */
1070 mark_temp_addr_taken (rtx x)
1072 struct temp_slot *p;
1077 /* If X is not in memory or is at a constant address, it cannot be in
1078 a temporary slot. */
1079 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1082 p = find_temp_slot_from_address (XEXP (x, 0));
1087 /* If X could be a reference to a temporary slot, mark that slot as
1088 belonging to the to one level higher than the current level. If X
1089 matched one of our slots, just mark that one. Otherwise, we can't
1090 easily predict which it is, so upgrade all of them. Kept slots
1091 need not be touched.
1093 This is called when an ({...}) construct occurs and a statement
1094 returns a value in memory. */
1097 preserve_temp_slots (rtx x)
1099 struct temp_slot *p = 0;
1101 /* If there is no result, we still might have some objects whose address
1102 were taken, so we need to make sure they stay around. */
1105 for (p = temp_slots; p; p = p->next)
1106 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1112 /* If X is a register that is being used as a pointer, see if we have
1113 a temporary slot we know it points to. To be consistent with
1114 the code below, we really should preserve all non-kept slots
1115 if we can't find a match, but that seems to be much too costly. */
1116 if (GET_CODE (x) == REG && REG_POINTER (x))
1117 p = find_temp_slot_from_address (x);
1119 /* If X is not in memory or is at a constant address, it cannot be in
1120 a temporary slot, but it can contain something whose address was
1122 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1124 for (p = temp_slots; p; p = p->next)
1125 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1131 /* First see if we can find a match. */
1133 p = find_temp_slot_from_address (XEXP (x, 0));
1137 /* Move everything at our level whose address was taken to our new
1138 level in case we used its address. */
1139 struct temp_slot *q;
1141 if (p->level == temp_slot_level)
1143 for (q = temp_slots; q; q = q->next)
1144 if (q != p && q->addr_taken && q->level == p->level)
1153 /* Otherwise, preserve all non-kept slots at this level. */
1154 for (p = temp_slots; p; p = p->next)
1155 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1159 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1160 with that RTL_EXPR, promote it into a temporary slot at the present
1161 level so it will not be freed when we free slots made in the
1165 preserve_rtl_expr_result (rtx x)
1167 struct temp_slot *p;
1169 /* If X is not in memory or is at a constant address, it cannot be in
1170 a temporary slot. */
1171 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1174 /* If we can find a match, move it to our level unless it is already at
1176 p = find_temp_slot_from_address (XEXP (x, 0));
1179 p->level = MIN (p->level, temp_slot_level);
1186 /* Free all temporaries used so far. This is normally called at the end
1187 of generating code for a statement. Don't free any temporaries
1188 currently in use for an RTL_EXPR that hasn't yet been emitted.
1189 We could eventually do better than this since it can be reused while
1190 generating the same RTL_EXPR, but this is complex and probably not
1194 free_temp_slots (void)
1196 struct temp_slot *p;
1198 for (p = temp_slots; p; p = p->next)
1199 if (p->in_use && p->level == temp_slot_level && ! p->keep
1200 && p->rtl_expr == 0)
1203 combine_temp_slots ();
1206 /* Free all temporary slots used in T, an RTL_EXPR node. */
1209 free_temps_for_rtl_expr (tree t)
1211 struct temp_slot *p;
1213 for (p = temp_slots; p; p = p->next)
1214 if (p->rtl_expr == t)
1216 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1217 needs to be preserved. This can happen if a temporary in
1218 the RTL_EXPR was addressed; preserve_temp_slots will move
1219 the temporary into a higher level. */
1220 if (temp_slot_level <= p->level)
1223 p->rtl_expr = NULL_TREE;
1226 combine_temp_slots ();
1229 /* Mark all temporaries ever allocated in this function as not suitable
1230 for reuse until the current level is exited. */
1233 mark_all_temps_used (void)
1235 struct temp_slot *p;
1237 for (p = temp_slots; p; p = p->next)
1239 p->in_use = p->keep = 1;
1240 p->level = MIN (p->level, temp_slot_level);
1244 /* Push deeper into the nesting level for stack temporaries. */
1247 push_temp_slots (void)
1252 /* Pop a temporary nesting level. All slots in use in the current level
1256 pop_temp_slots (void)
1258 struct temp_slot *p;
1260 for (p = temp_slots; p; p = p->next)
1261 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1264 combine_temp_slots ();
1269 /* Initialize temporary slots. */
1272 init_temp_slots (void)
1274 /* We have not allocated any temporaries yet. */
1276 temp_slot_level = 0;
1277 var_temp_slot_level = 0;
1278 target_temp_slot_level = 0;
1281 /* Retroactively move an auto variable from a register to a stack
1282 slot. This is done when an address-reference to the variable is
1283 seen. If RESCAN is true, all previously emitted instructions are
1284 examined and modified to handle the fact that DECL is now
1288 put_var_into_stack (tree decl, int rescan)
1291 enum machine_mode promoted_mode, decl_mode;
1292 struct function *function = 0;
1294 int can_use_addressof;
1295 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1296 int usedp = (TREE_USED (decl)
1297 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1299 context = decl_function_context (decl);
1301 /* Get the current rtl used for this object and its original mode. */
1302 reg = (TREE_CODE (decl) == SAVE_EXPR
1303 ? SAVE_EXPR_RTL (decl)
1304 : DECL_RTL_IF_SET (decl));
1306 /* No need to do anything if decl has no rtx yet
1307 since in that case caller is setting TREE_ADDRESSABLE
1308 and a stack slot will be assigned when the rtl is made. */
1312 /* Get the declared mode for this object. */
1313 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1314 : DECL_MODE (decl));
1315 /* Get the mode it's actually stored in. */
1316 promoted_mode = GET_MODE (reg);
1318 /* If this variable comes from an outer function, find that
1319 function's saved context. Don't use find_function_data here,
1320 because it might not be in any active function.
1321 FIXME: Is that really supposed to happen?
1322 It does in ObjC at least. */
1323 if (context != current_function_decl && context != inline_function_decl)
1324 for (function = outer_function_chain; function; function = function->outer)
1325 if (function->decl == context)
1328 /* If this is a variable-sized object or a structure passed by invisible
1329 reference, with a pseudo to address it, put that pseudo into the stack
1330 if the var is non-local. */
1331 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1332 && GET_CODE (reg) == MEM
1333 && GET_CODE (XEXP (reg, 0)) == REG
1334 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1336 reg = XEXP (reg, 0);
1337 decl_mode = promoted_mode = GET_MODE (reg);
1340 /* If this variable lives in the current function and we don't need to put it
1341 in the stack for the sake of setjmp or the non-locality, try to keep it in
1342 a register until we know we actually need the address. */
1345 && ! (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl))
1347 /* FIXME make it work for promoted modes too */
1348 && decl_mode == promoted_mode
1349 #ifdef NON_SAVING_SETJMP
1350 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1354 /* If we can't use ADDRESSOF, make sure we see through one we already
1356 if (! can_use_addressof && GET_CODE (reg) == MEM
1357 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1358 reg = XEXP (XEXP (reg, 0), 0);
1360 /* Now we should have a value that resides in one or more pseudo regs. */
1362 if (GET_CODE (reg) == REG)
1364 if (can_use_addressof)
1365 gen_mem_addressof (reg, decl, rescan);
1367 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1368 decl_mode, volatilep, 0, usedp, 0);
1370 else if (GET_CODE (reg) == CONCAT)
1372 /* A CONCAT contains two pseudos; put them both in the stack.
1373 We do it so they end up consecutive.
1374 We fixup references to the parts only after we fixup references
1375 to the whole CONCAT, lest we do double fixups for the latter
1377 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1378 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1379 rtx lopart = XEXP (reg, 0);
1380 rtx hipart = XEXP (reg, 1);
1381 #ifdef FRAME_GROWS_DOWNWARD
1382 /* Since part 0 should have a lower address, do it second. */
1383 put_reg_into_stack (function, hipart, part_type, part_mode,
1384 part_mode, volatilep, 0, 0, 0);
1385 put_reg_into_stack (function, lopart, part_type, part_mode,
1386 part_mode, volatilep, 0, 0, 0);
1388 put_reg_into_stack (function, lopart, part_type, part_mode,
1389 part_mode, volatilep, 0, 0, 0);
1390 put_reg_into_stack (function, hipart, part_type, part_mode,
1391 part_mode, volatilep, 0, 0, 0);
1394 /* Change the CONCAT into a combined MEM for both parts. */
1395 PUT_CODE (reg, MEM);
1396 MEM_ATTRS (reg) = 0;
1398 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1399 already computed alias sets. Here we want to re-generate. */
1401 SET_DECL_RTL (decl, NULL);
1402 set_mem_attributes (reg, decl, 1);
1404 SET_DECL_RTL (decl, reg);
1406 /* The two parts are in memory order already.
1407 Use the lower parts address as ours. */
1408 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1409 /* Prevent sharing of rtl that might lose. */
1410 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1411 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1412 if (usedp && rescan)
1414 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1416 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1417 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1424 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1425 into the stack frame of FUNCTION (0 means the current function).
1426 DECL_MODE is the machine mode of the user-level data type.
1427 PROMOTED_MODE is the machine mode of the register.
1428 VOLATILE_P is nonzero if this is for a "volatile" decl.
1429 USED_P is nonzero if this reg might have already been used in an insn. */
1432 put_reg_into_stack (struct function *function, rtx reg, tree type,
1433 enum machine_mode promoted_mode, enum machine_mode decl_mode,
1434 int volatile_p, unsigned int original_regno, int used_p, htab_t ht)
1436 struct function *func = function ? function : cfun;
1438 unsigned int regno = original_regno;
1441 regno = REGNO (reg);
1443 if (regno < func->x_max_parm_reg)
1444 new = func->x_parm_reg_stack_loc[regno];
1447 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1449 PUT_CODE (reg, MEM);
1450 PUT_MODE (reg, decl_mode);
1451 XEXP (reg, 0) = XEXP (new, 0);
1452 MEM_ATTRS (reg) = 0;
1453 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1454 MEM_VOLATILE_P (reg) = volatile_p;
1456 /* If this is a memory ref that contains aggregate components,
1457 mark it as such for cse and loop optimize. If we are reusing a
1458 previously generated stack slot, then we need to copy the bit in
1459 case it was set for other reasons. For instance, it is set for
1460 __builtin_va_alist. */
1463 MEM_SET_IN_STRUCT_P (reg,
1464 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1465 set_mem_alias_set (reg, get_alias_set (type));
1469 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1472 /* Make sure that all refs to the variable, previously made
1473 when it was a register, are fixed up to be valid again.
1474 See function above for meaning of arguments. */
1477 schedule_fixup_var_refs (struct function *function, rtx reg, tree type,
1478 enum machine_mode promoted_mode, htab_t ht)
1480 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1484 struct var_refs_queue *temp;
1486 temp = ggc_alloc (sizeof (struct var_refs_queue));
1487 temp->modified = reg;
1488 temp->promoted_mode = promoted_mode;
1489 temp->unsignedp = unsigned_p;
1490 temp->next = function->fixup_var_refs_queue;
1491 function->fixup_var_refs_queue = temp;
1494 /* Variable is local; fix it up now. */
1495 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1499 fixup_var_refs (rtx var, enum machine_mode promoted_mode, int unsignedp,
1500 rtx may_share, htab_t ht)
1503 rtx first_insn = get_insns ();
1504 struct sequence_stack *stack = seq_stack;
1505 tree rtl_exps = rtl_expr_chain;
1506 int save_volatile_ok = volatile_ok;
1508 /* If there's a hash table, it must record all uses of VAR. */
1513 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1518 /* Volatile is valid in MEMs because all we're doing in changing the
1521 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1522 stack == 0, may_share);
1524 /* Scan all pending sequences too. */
1525 for (; stack; stack = stack->next)
1527 push_to_full_sequence (stack->first, stack->last);
1528 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1529 stack->next != 0, may_share);
1530 /* Update remembered end of sequence
1531 in case we added an insn at the end. */
1532 stack->last = get_last_insn ();
1536 /* Scan all waiting RTL_EXPRs too. */
1537 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1539 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1540 if (seq != const0_rtx && seq != 0)
1542 push_to_sequence (seq);
1543 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1549 volatile_ok = save_volatile_ok;
1552 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1553 some part of an insn. Return a struct fixup_replacement whose OLD
1554 value is equal to X. Allocate a new structure if no such entry exists. */
1556 static struct fixup_replacement *
1557 find_fixup_replacement (struct fixup_replacement **replacements, rtx x)
1559 struct fixup_replacement *p;
1561 /* See if we have already replaced this. */
1562 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1567 p = xmalloc (sizeof (struct fixup_replacement));
1570 p->next = *replacements;
1577 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1578 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1579 for the current function. MAY_SHARE is either a MEM that is not
1580 to be unshared or a list of them. */
1583 fixup_var_refs_insns (rtx insn, rtx var, enum machine_mode promoted_mode,
1584 int unsignedp, int toplevel, rtx may_share)
1588 /* fixup_var_refs_insn might modify insn, so save its next
1590 rtx next = NEXT_INSN (insn);
1592 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1593 the three sequences they (potentially) contain, and process
1594 them recursively. The CALL_INSN itself is not interesting. */
1596 if (GET_CODE (insn) == CALL_INSN
1597 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1601 /* Look at the Normal call, sibling call and tail recursion
1602 sequences attached to the CALL_PLACEHOLDER. */
1603 for (i = 0; i < 3; i++)
1605 rtx seq = XEXP (PATTERN (insn), i);
1608 push_to_sequence (seq);
1609 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1611 XEXP (PATTERN (insn), i) = get_insns ();
1617 else if (INSN_P (insn))
1618 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1625 /* Look up the insns which reference VAR in HT and fix them up. Other
1626 arguments are the same as fixup_var_refs_insns.
1628 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1629 because the hash table will point straight to the interesting insn
1630 (inside the CALL_PLACEHOLDER). */
1633 fixup_var_refs_insns_with_hash (htab_t ht, rtx var, enum machine_mode promoted_mode,
1634 int unsignedp, rtx may_share)
1636 struct insns_for_mem_entry tmp;
1637 struct insns_for_mem_entry *ime;
1641 ime = htab_find (ht, &tmp);
1642 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1643 if (INSN_P (XEXP (insn_list, 0)))
1644 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1645 unsignedp, 1, may_share);
1649 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1650 the insn under examination, VAR is the variable to fix up
1651 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1652 TOPLEVEL is nonzero if this is the main insn chain for this
1656 fixup_var_refs_insn (rtx insn, rtx var, enum machine_mode promoted_mode,
1657 int unsignedp, int toplevel, rtx no_share)
1660 rtx set, prev, prev_set;
1663 /* Remember the notes in case we delete the insn. */
1664 note = REG_NOTES (insn);
1666 /* If this is a CLOBBER of VAR, delete it.
1668 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1669 and REG_RETVAL notes too. */
1670 if (GET_CODE (PATTERN (insn)) == CLOBBER
1671 && (XEXP (PATTERN (insn), 0) == var
1672 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1673 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1674 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1676 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1677 /* The REG_LIBCALL note will go away since we are going to
1678 turn INSN into a NOTE, so just delete the
1679 corresponding REG_RETVAL note. */
1680 remove_note (XEXP (note, 0),
1681 find_reg_note (XEXP (note, 0), REG_RETVAL,
1687 /* The insn to load VAR from a home in the arglist
1688 is now a no-op. When we see it, just delete it.
1689 Similarly if this is storing VAR from a register from which
1690 it was loaded in the previous insn. This will occur
1691 when an ADDRESSOF was made for an arglist slot. */
1693 && (set = single_set (insn)) != 0
1694 && SET_DEST (set) == var
1695 /* If this represents the result of an insn group,
1696 don't delete the insn. */
1697 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1698 && (rtx_equal_p (SET_SRC (set), var)
1699 || (GET_CODE (SET_SRC (set)) == REG
1700 && (prev = prev_nonnote_insn (insn)) != 0
1701 && (prev_set = single_set (prev)) != 0
1702 && SET_DEST (prev_set) == SET_SRC (set)
1703 && rtx_equal_p (SET_SRC (prev_set), var))))
1709 struct fixup_replacement *replacements = 0;
1710 rtx next_insn = NEXT_INSN (insn);
1712 if (SMALL_REGISTER_CLASSES)
1714 /* If the insn that copies the results of a CALL_INSN
1715 into a pseudo now references VAR, we have to use an
1716 intermediate pseudo since we want the life of the
1717 return value register to be only a single insn.
1719 If we don't use an intermediate pseudo, such things as
1720 address computations to make the address of VAR valid
1721 if it is not can be placed between the CALL_INSN and INSN.
1723 To make sure this doesn't happen, we record the destination
1724 of the CALL_INSN and see if the next insn uses both that
1727 if (call_dest != 0 && GET_CODE (insn) == INSN
1728 && reg_mentioned_p (var, PATTERN (insn))
1729 && reg_mentioned_p (call_dest, PATTERN (insn)))
1731 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1733 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1735 PATTERN (insn) = replace_rtx (PATTERN (insn),
1739 if (GET_CODE (insn) == CALL_INSN
1740 && GET_CODE (PATTERN (insn)) == SET)
1741 call_dest = SET_DEST (PATTERN (insn));
1742 else if (GET_CODE (insn) == CALL_INSN
1743 && GET_CODE (PATTERN (insn)) == PARALLEL
1744 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1745 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1750 /* See if we have to do anything to INSN now that VAR is in
1751 memory. If it needs to be loaded into a pseudo, use a single
1752 pseudo for the entire insn in case there is a MATCH_DUP
1753 between two operands. We pass a pointer to the head of
1754 a list of struct fixup_replacements. If fixup_var_refs_1
1755 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1756 it will record them in this list.
1758 If it allocated a pseudo for any replacement, we copy into
1761 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1762 &replacements, no_share);
1764 /* If this is last_parm_insn, and any instructions were output
1765 after it to fix it up, then we must set last_parm_insn to
1766 the last such instruction emitted. */
1767 if (insn == last_parm_insn)
1768 last_parm_insn = PREV_INSN (next_insn);
1770 while (replacements)
1772 struct fixup_replacement *next;
1774 if (GET_CODE (replacements->new) == REG)
1779 /* OLD might be a (subreg (mem)). */
1780 if (GET_CODE (replacements->old) == SUBREG)
1782 = fixup_memory_subreg (replacements->old, insn,
1786 = fixup_stack_1 (replacements->old, insn);
1788 insert_before = insn;
1790 /* If we are changing the mode, do a conversion.
1791 This might be wasteful, but combine.c will
1792 eliminate much of the waste. */
1794 if (GET_MODE (replacements->new)
1795 != GET_MODE (replacements->old))
1798 convert_move (replacements->new,
1799 replacements->old, unsignedp);
1804 seq = gen_move_insn (replacements->new,
1807 emit_insn_before (seq, insert_before);
1810 next = replacements->next;
1811 free (replacements);
1812 replacements = next;
1816 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1817 But don't touch other insns referred to by reg-notes;
1818 we will get them elsewhere. */
1821 if (GET_CODE (note) != INSN_LIST)
1823 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1825 note = XEXP (note, 1);
1829 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1830 See if the rtx expression at *LOC in INSN needs to be changed.
1832 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1833 contain a list of original rtx's and replacements. If we find that we need
1834 to modify this insn by replacing a memory reference with a pseudo or by
1835 making a new MEM to implement a SUBREG, we consult that list to see if
1836 we have already chosen a replacement. If none has already been allocated,
1837 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1838 or the SUBREG, as appropriate, to the pseudo. */
1841 fixup_var_refs_1 (rtx var, enum machine_mode promoted_mode, rtx *loc, rtx insn,
1842 struct fixup_replacement **replacements, rtx no_share)
1846 RTX_CODE code = GET_CODE (x);
1849 struct fixup_replacement *replacement;
1854 if (XEXP (x, 0) == var)
1856 /* Prevent sharing of rtl that might lose. */
1857 rtx sub = copy_rtx (XEXP (var, 0));
1859 if (! validate_change (insn, loc, sub, 0))
1861 rtx y = gen_reg_rtx (GET_MODE (sub));
1864 /* We should be able to replace with a register or all is lost.
1865 Note that we can't use validate_change to verify this, since
1866 we're not caring for replacing all dups simultaneously. */
1867 if (! validate_replace_rtx (*loc, y, insn))
1870 /* Careful! First try to recognize a direct move of the
1871 value, mimicking how things are done in gen_reload wrt
1872 PLUS. Consider what happens when insn is a conditional
1873 move instruction and addsi3 clobbers flags. */
1876 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1880 if (recog_memoized (new_insn) < 0)
1882 /* That failed. Fall back on force_operand and hope. */
1885 sub = force_operand (sub, y);
1887 emit_insn (gen_move_insn (y, sub));
1893 /* Don't separate setter from user. */
1894 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1895 insn = PREV_INSN (insn);
1898 emit_insn_before (seq, insn);
1906 /* If we already have a replacement, use it. Otherwise,
1907 try to fix up this address in case it is invalid. */
1909 replacement = find_fixup_replacement (replacements, var);
1910 if (replacement->new)
1912 *loc = replacement->new;
1916 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1918 /* Unless we are forcing memory to register or we changed the mode,
1919 we can leave things the way they are if the insn is valid. */
1921 INSN_CODE (insn) = -1;
1922 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1923 && recog_memoized (insn) >= 0)
1926 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1930 /* If X contains VAR, we need to unshare it here so that we update
1931 each occurrence separately. But all identical MEMs in one insn
1932 must be replaced with the same rtx because of the possibility of
1935 if (reg_mentioned_p (var, x))
1937 replacement = find_fixup_replacement (replacements, x);
1938 if (replacement->new == 0)
1939 replacement->new = copy_most_rtx (x, no_share);
1941 *loc = x = replacement->new;
1942 code = GET_CODE (x);
1959 /* Note that in some cases those types of expressions are altered
1960 by optimize_bit_field, and do not survive to get here. */
1961 if (XEXP (x, 0) == var
1962 || (GET_CODE (XEXP (x, 0)) == SUBREG
1963 && SUBREG_REG (XEXP (x, 0)) == var))
1965 /* Get TEM as a valid MEM in the mode presently in the insn.
1967 We don't worry about the possibility of MATCH_DUP here; it
1968 is highly unlikely and would be tricky to handle. */
1971 if (GET_CODE (tem) == SUBREG)
1973 if (GET_MODE_BITSIZE (GET_MODE (tem))
1974 > GET_MODE_BITSIZE (GET_MODE (var)))
1976 replacement = find_fixup_replacement (replacements, var);
1977 if (replacement->new == 0)
1978 replacement->new = gen_reg_rtx (GET_MODE (var));
1979 SUBREG_REG (tem) = replacement->new;
1981 /* The following code works only if we have a MEM, so we
1982 need to handle the subreg here. We directly substitute
1983 it assuming that a subreg must be OK here. We already
1984 scheduled a replacement to copy the mem into the
1990 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
1993 tem = fixup_stack_1 (tem, insn);
1995 /* Unless we want to load from memory, get TEM into the proper mode
1996 for an extract from memory. This can only be done if the
1997 extract is at a constant position and length. */
1999 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2000 && GET_CODE (XEXP (x, 2)) == CONST_INT
2001 && ! mode_dependent_address_p (XEXP (tem, 0))
2002 && ! MEM_VOLATILE_P (tem))
2004 enum machine_mode wanted_mode = VOIDmode;
2005 enum machine_mode is_mode = GET_MODE (tem);
2006 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2008 if (GET_CODE (x) == ZERO_EXTRACT)
2010 enum machine_mode new_mode
2011 = mode_for_extraction (EP_extzv, 1);
2012 if (new_mode != MAX_MACHINE_MODE)
2013 wanted_mode = new_mode;
2015 else if (GET_CODE (x) == SIGN_EXTRACT)
2017 enum machine_mode new_mode
2018 = mode_for_extraction (EP_extv, 1);
2019 if (new_mode != MAX_MACHINE_MODE)
2020 wanted_mode = new_mode;
2023 /* If we have a narrower mode, we can do something. */
2024 if (wanted_mode != VOIDmode
2025 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2027 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2028 rtx old_pos = XEXP (x, 2);
2031 /* If the bytes and bits are counted differently, we
2032 must adjust the offset. */
2033 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2034 offset = (GET_MODE_SIZE (is_mode)
2035 - GET_MODE_SIZE (wanted_mode) - offset);
2037 pos %= GET_MODE_BITSIZE (wanted_mode);
2039 newmem = adjust_address_nv (tem, wanted_mode, offset);
2041 /* Make the change and see if the insn remains valid. */
2042 INSN_CODE (insn) = -1;
2043 XEXP (x, 0) = newmem;
2044 XEXP (x, 2) = GEN_INT (pos);
2046 if (recog_memoized (insn) >= 0)
2049 /* Otherwise, restore old position. XEXP (x, 0) will be
2051 XEXP (x, 2) = old_pos;
2055 /* If we get here, the bitfield extract insn can't accept a memory
2056 reference. Copy the input into a register. */
2058 tem1 = gen_reg_rtx (GET_MODE (tem));
2059 emit_insn_before (gen_move_insn (tem1, tem), insn);
2066 if (SUBREG_REG (x) == var)
2068 /* If this is a special SUBREG made because VAR was promoted
2069 from a wider mode, replace it with VAR and call ourself
2070 recursively, this time saying that the object previously
2071 had its current mode (by virtue of the SUBREG). */
2073 if (SUBREG_PROMOTED_VAR_P (x))
2076 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2081 /* If this SUBREG makes VAR wider, it has become a paradoxical
2082 SUBREG with VAR in memory, but these aren't allowed at this
2083 stage of the compilation. So load VAR into a pseudo and take
2084 a SUBREG of that pseudo. */
2085 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2087 replacement = find_fixup_replacement (replacements, var);
2088 if (replacement->new == 0)
2089 replacement->new = gen_reg_rtx (promoted_mode);
2090 SUBREG_REG (x) = replacement->new;
2094 /* See if we have already found a replacement for this SUBREG.
2095 If so, use it. Otherwise, make a MEM and see if the insn
2096 is recognized. If not, or if we should force MEM into a register,
2097 make a pseudo for this SUBREG. */
2098 replacement = find_fixup_replacement (replacements, x);
2099 if (replacement->new)
2101 enum machine_mode mode = GET_MODE (x);
2102 *loc = replacement->new;
2104 /* Careful! We may have just replaced a SUBREG by a MEM, which
2105 means that the insn may have become invalid again. We can't
2106 in this case make a new replacement since we already have one
2107 and we must deal with MATCH_DUPs. */
2108 if (GET_CODE (replacement->new) == MEM)
2110 INSN_CODE (insn) = -1;
2111 if (recog_memoized (insn) >= 0)
2114 fixup_var_refs_1 (replacement->new, mode, &PATTERN (insn),
2115 insn, replacements, no_share);
2121 replacement->new = *loc = fixup_memory_subreg (x, insn,
2124 INSN_CODE (insn) = -1;
2125 if (! flag_force_mem && recog_memoized (insn) >= 0)
2128 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2134 /* First do special simplification of bit-field references. */
2135 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2136 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2137 optimize_bit_field (x, insn, 0);
2138 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2139 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2140 optimize_bit_field (x, insn, 0);
2142 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2143 into a register and then store it back out. */
2144 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2145 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2146 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2147 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2148 > GET_MODE_SIZE (GET_MODE (var))))
2150 replacement = find_fixup_replacement (replacements, var);
2151 if (replacement->new == 0)
2152 replacement->new = gen_reg_rtx (GET_MODE (var));
2154 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2155 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2158 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2159 insn into a pseudo and store the low part of the pseudo into VAR. */
2160 if (GET_CODE (SET_DEST (x)) == SUBREG
2161 && SUBREG_REG (SET_DEST (x)) == var
2162 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2163 > GET_MODE_SIZE (GET_MODE (var))))
2165 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2166 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2173 rtx dest = SET_DEST (x);
2174 rtx src = SET_SRC (x);
2175 rtx outerdest = dest;
2177 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2178 || GET_CODE (dest) == SIGN_EXTRACT
2179 || GET_CODE (dest) == ZERO_EXTRACT)
2180 dest = XEXP (dest, 0);
2182 if (GET_CODE (src) == SUBREG)
2183 src = SUBREG_REG (src);
2185 /* If VAR does not appear at the top level of the SET
2186 just scan the lower levels of the tree. */
2188 if (src != var && dest != var)
2191 /* We will need to rerecognize this insn. */
2192 INSN_CODE (insn) = -1;
2194 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2195 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2197 /* Since this case will return, ensure we fixup all the
2199 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2200 insn, replacements, no_share);
2201 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2202 insn, replacements, no_share);
2203 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2204 insn, replacements, no_share);
2206 tem = XEXP (outerdest, 0);
2208 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2209 that may appear inside a ZERO_EXTRACT.
2210 This was legitimate when the MEM was a REG. */
2211 if (GET_CODE (tem) == SUBREG
2212 && SUBREG_REG (tem) == var)
2213 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2215 tem = fixup_stack_1 (tem, insn);
2217 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2218 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2219 && ! mode_dependent_address_p (XEXP (tem, 0))
2220 && ! MEM_VOLATILE_P (tem))
2222 enum machine_mode wanted_mode;
2223 enum machine_mode is_mode = GET_MODE (tem);
2224 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2226 wanted_mode = mode_for_extraction (EP_insv, 0);
2228 /* If we have a narrower mode, we can do something. */
2229 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2231 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2232 rtx old_pos = XEXP (outerdest, 2);
2235 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2236 offset = (GET_MODE_SIZE (is_mode)
2237 - GET_MODE_SIZE (wanted_mode) - offset);
2239 pos %= GET_MODE_BITSIZE (wanted_mode);
2241 newmem = adjust_address_nv (tem, wanted_mode, offset);
2243 /* Make the change and see if the insn remains valid. */
2244 INSN_CODE (insn) = -1;
2245 XEXP (outerdest, 0) = newmem;
2246 XEXP (outerdest, 2) = GEN_INT (pos);
2248 if (recog_memoized (insn) >= 0)
2251 /* Otherwise, restore old position. XEXP (x, 0) will be
2253 XEXP (outerdest, 2) = old_pos;
2257 /* If we get here, the bit-field store doesn't allow memory
2258 or isn't located at a constant position. Load the value into
2259 a register, do the store, and put it back into memory. */
2261 tem1 = gen_reg_rtx (GET_MODE (tem));
2262 emit_insn_before (gen_move_insn (tem1, tem), insn);
2263 emit_insn_after (gen_move_insn (tem, tem1), insn);
2264 XEXP (outerdest, 0) = tem1;
2268 /* STRICT_LOW_PART is a no-op on memory references
2269 and it can cause combinations to be unrecognizable,
2272 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2273 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2275 /* A valid insn to copy VAR into or out of a register
2276 must be left alone, to avoid an infinite loop here.
2277 If the reference to VAR is by a subreg, fix that up,
2278 since SUBREG is not valid for a memref.
2279 Also fix up the address of the stack slot.
2281 Note that we must not try to recognize the insn until
2282 after we know that we have valid addresses and no
2283 (subreg (mem ...) ...) constructs, since these interfere
2284 with determining the validity of the insn. */
2286 if ((SET_SRC (x) == var
2287 || (GET_CODE (SET_SRC (x)) == SUBREG
2288 && SUBREG_REG (SET_SRC (x)) == var))
2289 && (GET_CODE (SET_DEST (x)) == REG
2290 || (GET_CODE (SET_DEST (x)) == SUBREG
2291 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2292 && GET_MODE (var) == promoted_mode
2293 && x == single_set (insn))
2297 if (GET_CODE (SET_SRC (x)) == SUBREG
2298 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2299 > GET_MODE_SIZE (GET_MODE (var))))
2301 /* This (subreg VAR) is now a paradoxical subreg. We need
2302 to replace VAR instead of the subreg. */
2303 replacement = find_fixup_replacement (replacements, var);
2304 if (replacement->new == NULL_RTX)
2305 replacement->new = gen_reg_rtx (GET_MODE (var));
2306 SUBREG_REG (SET_SRC (x)) = replacement->new;
2310 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2311 if (replacement->new)
2312 SET_SRC (x) = replacement->new;
2313 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2314 SET_SRC (x) = replacement->new
2315 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2318 SET_SRC (x) = replacement->new
2319 = fixup_stack_1 (SET_SRC (x), insn);
2322 if (recog_memoized (insn) >= 0)
2325 /* INSN is not valid, but we know that we want to
2326 copy SET_SRC (x) to SET_DEST (x) in some way. So
2327 we generate the move and see whether it requires more
2328 than one insn. If it does, we emit those insns and
2329 delete INSN. Otherwise, we can just replace the pattern
2330 of INSN; we have already verified above that INSN has
2331 no other function that to do X. */
2333 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2334 if (NEXT_INSN (pat) != NULL_RTX)
2336 last = emit_insn_before (pat, insn);
2338 /* INSN might have REG_RETVAL or other important notes, so
2339 we need to store the pattern of the last insn in the
2340 sequence into INSN similarly to the normal case. LAST
2341 should not have REG_NOTES, but we allow them if INSN has
2343 if (REG_NOTES (last) && REG_NOTES (insn))
2345 if (REG_NOTES (last))
2346 REG_NOTES (insn) = REG_NOTES (last);
2347 PATTERN (insn) = PATTERN (last);
2352 PATTERN (insn) = PATTERN (pat);
2357 if ((SET_DEST (x) == var
2358 || (GET_CODE (SET_DEST (x)) == SUBREG
2359 && SUBREG_REG (SET_DEST (x)) == var))
2360 && (GET_CODE (SET_SRC (x)) == REG
2361 || (GET_CODE (SET_SRC (x)) == SUBREG
2362 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2363 && GET_MODE (var) == promoted_mode
2364 && x == single_set (insn))
2368 if (GET_CODE (SET_DEST (x)) == SUBREG)
2369 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2372 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2374 if (recog_memoized (insn) >= 0)
2377 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2378 if (NEXT_INSN (pat) != NULL_RTX)
2380 last = emit_insn_before (pat, insn);
2382 /* INSN might have REG_RETVAL or other important notes, so
2383 we need to store the pattern of the last insn in the
2384 sequence into INSN similarly to the normal case. LAST
2385 should not have REG_NOTES, but we allow them if INSN has
2387 if (REG_NOTES (last) && REG_NOTES (insn))
2389 if (REG_NOTES (last))
2390 REG_NOTES (insn) = REG_NOTES (last);
2391 PATTERN (insn) = PATTERN (last);
2396 PATTERN (insn) = PATTERN (pat);
2401 /* Otherwise, storing into VAR must be handled specially
2402 by storing into a temporary and copying that into VAR
2403 with a new insn after this one. Note that this case
2404 will be used when storing into a promoted scalar since
2405 the insn will now have different modes on the input
2406 and output and hence will be invalid (except for the case
2407 of setting it to a constant, which does not need any
2408 change if it is valid). We generate extra code in that case,
2409 but combine.c will eliminate it. */
2414 rtx fixeddest = SET_DEST (x);
2415 enum machine_mode temp_mode;
2417 /* STRICT_LOW_PART can be discarded, around a MEM. */
2418 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2419 fixeddest = XEXP (fixeddest, 0);
2420 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2421 if (GET_CODE (fixeddest) == SUBREG)
2423 fixeddest = fixup_memory_subreg (fixeddest, insn,
2425 temp_mode = GET_MODE (fixeddest);
2429 fixeddest = fixup_stack_1 (fixeddest, insn);
2430 temp_mode = promoted_mode;
2433 temp = gen_reg_rtx (temp_mode);
2435 emit_insn_after (gen_move_insn (fixeddest,
2436 gen_lowpart (GET_MODE (fixeddest),
2440 SET_DEST (x) = temp;
2448 /* Nothing special about this RTX; fix its operands. */
2450 fmt = GET_RTX_FORMAT (code);
2451 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2454 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2456 else if (fmt[i] == 'E')
2459 for (j = 0; j < XVECLEN (x, i); j++)
2460 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2461 insn, replacements, no_share);
2466 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2467 The REG was placed on the stack, so X now has the form (SUBREG:m1
2470 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2471 must be emitted to compute NEWADDR, put them before INSN.
2473 UNCRITICAL nonzero means accept paradoxical subregs.
2474 This is used for subregs found inside REG_NOTES. */
2477 fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode, int uncritical)
2480 rtx mem = SUBREG_REG (x);
2481 rtx addr = XEXP (mem, 0);
2482 enum machine_mode mode = GET_MODE (x);
2485 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2486 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2489 offset = SUBREG_BYTE (x);
2490 if (BYTES_BIG_ENDIAN)
2491 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2492 the offset so that it points to the right location within the
2494 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2496 if (!flag_force_addr
2497 && memory_address_p (mode, plus_constant (addr, offset)))
2498 /* Shortcut if no insns need be emitted. */
2499 return adjust_address (mem, mode, offset);
2502 result = adjust_address (mem, mode, offset);
2506 emit_insn_before (seq, insn);
2510 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2511 Replace subexpressions of X in place.
2512 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2513 Otherwise return X, with its contents possibly altered.
2515 INSN, PROMOTED_MODE and UNCRITICAL are as for
2516 fixup_memory_subreg. */
2519 walk_fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode,
2529 code = GET_CODE (x);
2531 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2532 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2534 /* Nothing special about this RTX; fix its operands. */
2536 fmt = GET_RTX_FORMAT (code);
2537 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2540 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2541 promoted_mode, uncritical);
2542 else if (fmt[i] == 'E')
2545 for (j = 0; j < XVECLEN (x, i); j++)
2547 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2548 promoted_mode, uncritical);
2554 /* For each memory ref within X, if it refers to a stack slot
2555 with an out of range displacement, put the address in a temp register
2556 (emitting new insns before INSN to load these registers)
2557 and alter the memory ref to use that register.
2558 Replace each such MEM rtx with a copy, to avoid clobberage. */
2561 fixup_stack_1 (rtx x, rtx insn)
2564 RTX_CODE code = GET_CODE (x);
2569 rtx ad = XEXP (x, 0);
2570 /* If we have address of a stack slot but it's not valid
2571 (displacement is too large), compute the sum in a register. */
2572 if (GET_CODE (ad) == PLUS
2573 && GET_CODE (XEXP (ad, 0)) == REG
2574 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2575 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2576 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2577 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2578 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2580 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2581 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2582 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2583 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2586 if (memory_address_p (GET_MODE (x), ad))
2590 temp = copy_to_reg (ad);
2593 emit_insn_before (seq, insn);
2594 return replace_equiv_address (x, temp);
2599 fmt = GET_RTX_FORMAT (code);
2600 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2603 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2604 else if (fmt[i] == 'E')
2607 for (j = 0; j < XVECLEN (x, i); j++)
2608 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2614 /* Optimization: a bit-field instruction whose field
2615 happens to be a byte or halfword in memory
2616 can be changed to a move instruction.
2618 We call here when INSN is an insn to examine or store into a bit-field.
2619 BODY is the SET-rtx to be altered.
2621 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2622 (Currently this is called only from function.c, and EQUIV_MEM
2626 optimize_bit_field (rtx body, rtx insn, rtx *equiv_mem)
2631 enum machine_mode mode;
2633 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2634 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2635 bitfield = SET_DEST (body), destflag = 1;
2637 bitfield = SET_SRC (body), destflag = 0;
2639 /* First check that the field being stored has constant size and position
2640 and is in fact a byte or halfword suitably aligned. */
2642 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2643 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2644 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2646 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2650 /* Now check that the containing word is memory, not a register,
2651 and that it is safe to change the machine mode. */
2653 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2654 memref = XEXP (bitfield, 0);
2655 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2657 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2658 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2659 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2660 memref = SUBREG_REG (XEXP (bitfield, 0));
2661 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2663 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2664 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2667 && ! mode_dependent_address_p (XEXP (memref, 0))
2668 && ! MEM_VOLATILE_P (memref))
2670 /* Now adjust the address, first for any subreg'ing
2671 that we are now getting rid of,
2672 and then for which byte of the word is wanted. */
2674 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2677 /* Adjust OFFSET to count bits from low-address byte. */
2678 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2679 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2680 - offset - INTVAL (XEXP (bitfield, 1)));
2682 /* Adjust OFFSET to count bytes from low-address byte. */
2683 offset /= BITS_PER_UNIT;
2684 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2686 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2687 / UNITS_PER_WORD) * UNITS_PER_WORD;
2688 if (BYTES_BIG_ENDIAN)
2689 offset -= (MIN (UNITS_PER_WORD,
2690 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2691 - MIN (UNITS_PER_WORD,
2692 GET_MODE_SIZE (GET_MODE (memref))));
2696 memref = adjust_address (memref, mode, offset);
2697 insns = get_insns ();
2699 emit_insn_before (insns, insn);
2701 /* Store this memory reference where
2702 we found the bit field reference. */
2706 validate_change (insn, &SET_DEST (body), memref, 1);
2707 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2709 rtx src = SET_SRC (body);
2710 while (GET_CODE (src) == SUBREG
2711 && SUBREG_BYTE (src) == 0)
2712 src = SUBREG_REG (src);
2713 if (GET_MODE (src) != GET_MODE (memref))
2714 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2715 validate_change (insn, &SET_SRC (body), src, 1);
2717 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2718 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2719 /* This shouldn't happen because anything that didn't have
2720 one of these modes should have got converted explicitly
2721 and then referenced through a subreg.
2722 This is so because the original bit-field was
2723 handled by agg_mode and so its tree structure had
2724 the same mode that memref now has. */
2729 rtx dest = SET_DEST (body);
2731 while (GET_CODE (dest) == SUBREG
2732 && SUBREG_BYTE (dest) == 0
2733 && (GET_MODE_CLASS (GET_MODE (dest))
2734 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2735 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2737 dest = SUBREG_REG (dest);
2739 validate_change (insn, &SET_DEST (body), dest, 1);
2741 if (GET_MODE (dest) == GET_MODE (memref))
2742 validate_change (insn, &SET_SRC (body), memref, 1);
2745 /* Convert the mem ref to the destination mode. */
2746 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2749 convert_move (newreg, memref,
2750 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2754 validate_change (insn, &SET_SRC (body), newreg, 1);
2758 /* See if we can convert this extraction or insertion into
2759 a simple move insn. We might not be able to do so if this
2760 was, for example, part of a PARALLEL.
2762 If we succeed, write out any needed conversions. If we fail,
2763 it is hard to guess why we failed, so don't do anything
2764 special; just let the optimization be suppressed. */
2766 if (apply_change_group () && seq)
2767 emit_insn_before (seq, insn);
2772 /* These routines are responsible for converting virtual register references
2773 to the actual hard register references once RTL generation is complete.
2775 The following four variables are used for communication between the
2776 routines. They contain the offsets of the virtual registers from their
2777 respective hard registers. */
2779 static int in_arg_offset;
2780 static int var_offset;
2781 static int dynamic_offset;
2782 static int out_arg_offset;
2783 static int cfa_offset;
2785 /* In most machines, the stack pointer register is equivalent to the bottom
2788 #ifndef STACK_POINTER_OFFSET
2789 #define STACK_POINTER_OFFSET 0
2792 /* If not defined, pick an appropriate default for the offset of dynamically
2793 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2794 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2796 #ifndef STACK_DYNAMIC_OFFSET
2798 /* The bottom of the stack points to the actual arguments. If
2799 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2800 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2801 stack space for register parameters is not pushed by the caller, but
2802 rather part of the fixed stack areas and hence not included in
2803 `current_function_outgoing_args_size'. Nevertheless, we must allow
2804 for it when allocating stack dynamic objects. */
2806 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2807 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2808 ((ACCUMULATE_OUTGOING_ARGS \
2809 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2810 + (STACK_POINTER_OFFSET)) \
2813 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2814 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2815 + (STACK_POINTER_OFFSET))
2819 /* On most machines, the CFA coincides with the first incoming parm. */
2821 #ifndef ARG_POINTER_CFA_OFFSET
2822 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2825 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2826 had its address taken. DECL is the decl or SAVE_EXPR for the
2827 object stored in the register, for later use if we do need to force
2828 REG into the stack. REG is overwritten by the MEM like in
2829 put_reg_into_stack. RESCAN is true if previously emitted
2830 instructions must be rescanned and modified now that the REG has
2831 been transformed. */
2834 gen_mem_addressof (rtx reg, tree decl, int rescan)
2836 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2839 /* Calculate this before we start messing with decl's RTL. */
2840 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2842 /* If the original REG was a user-variable, then so is the REG whose
2843 address is being taken. Likewise for unchanging. */
2844 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2845 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2847 PUT_CODE (reg, MEM);
2848 MEM_ATTRS (reg) = 0;
2853 tree type = TREE_TYPE (decl);
2854 enum machine_mode decl_mode
2855 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2856 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2857 : DECL_RTL_IF_SET (decl));
2859 PUT_MODE (reg, decl_mode);
2861 /* Clear DECL_RTL momentarily so functions below will work
2862 properly, then set it again. */
2863 if (DECL_P (decl) && decl_rtl == reg)
2864 SET_DECL_RTL (decl, 0);
2866 set_mem_attributes (reg, decl, 1);
2867 set_mem_alias_set (reg, set);
2869 if (DECL_P (decl) && decl_rtl == reg)
2870 SET_DECL_RTL (decl, reg);
2873 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0)))
2874 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2878 /* This can only happen during reload. Clear the same flag bits as
2880 MEM_VOLATILE_P (reg) = 0;
2881 RTX_UNCHANGING_P (reg) = 0;
2882 MEM_IN_STRUCT_P (reg) = 0;
2883 MEM_SCALAR_P (reg) = 0;
2884 MEM_ATTRS (reg) = 0;
2886 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2892 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2895 flush_addressof (tree decl)
2897 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2898 && DECL_RTL (decl) != 0
2899 && GET_CODE (DECL_RTL (decl)) == MEM
2900 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2901 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2902 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2905 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2908 put_addressof_into_stack (rtx r, htab_t ht)
2911 int volatile_p, used_p;
2913 rtx reg = XEXP (r, 0);
2915 if (GET_CODE (reg) != REG)
2918 decl = ADDRESSOF_DECL (r);
2921 type = TREE_TYPE (decl);
2922 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2923 && TREE_THIS_VOLATILE (decl));
2924 used_p = (TREE_USED (decl)
2925 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2934 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2935 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2938 /* List of replacements made below in purge_addressof_1 when creating
2939 bitfield insertions. */
2940 static rtx purge_bitfield_addressof_replacements;
2942 /* List of replacements made below in purge_addressof_1 for patterns
2943 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2944 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2945 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2946 enough in complex cases, e.g. when some field values can be
2947 extracted by usage MEM with narrower mode. */
2948 static rtx purge_addressof_replacements;
2950 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2951 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2952 the stack. If the function returns FALSE then the replacement could not
2953 be made. If MAY_POSTPONE is true and we would not put the addressof
2954 to stack, postpone processing of the insn. */
2957 purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
2965 bool libcall = false;
2967 /* Re-start here to avoid recursion in common cases. */
2974 /* Is this a libcall? */
2976 libcall = REG_NOTE_KIND (*loc) == REG_RETVAL;
2978 code = GET_CODE (x);
2980 /* If we don't return in any of the cases below, we will recurse inside
2981 the RTX, which will normally result in any ADDRESSOF being forced into
2985 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1,
2987 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0,
2991 else if (code == ADDRESSOF)
2995 if (GET_CODE (XEXP (x, 0)) != MEM)
2996 put_addressof_into_stack (x, ht);
2998 /* We must create a copy of the rtx because it was created by
2999 overwriting a REG rtx which is always shared. */
3000 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3001 if (validate_change (insn, loc, sub, 0)
3002 || validate_replace_rtx (x, sub, insn))
3007 /* If SUB is a hard or virtual register, try it as a pseudo-register.
3008 Otherwise, perhaps SUB is an expression, so generate code to compute
3010 if (GET_CODE (sub) == REG && REGNO (sub) <= LAST_VIRTUAL_REGISTER)
3011 sub = copy_to_reg (sub);
3013 sub = force_operand (sub, NULL_RTX);
3015 if (! validate_change (insn, loc, sub, 0)
3016 && ! validate_replace_rtx (x, sub, insn))
3019 insns = get_insns ();
3021 emit_insn_before (insns, insn);
3025 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3027 rtx sub = XEXP (XEXP (x, 0), 0);
3029 if (GET_CODE (sub) == MEM)
3030 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3031 else if (GET_CODE (sub) == REG
3032 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3034 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3036 int size_x, size_sub;
3040 /* Postpone for now, so that we do not emit bitfield arithmetics
3041 unless there is some benefit from it. */
3042 if (!postponed_insns || XEXP (postponed_insns, 0) != insn)
3043 postponed_insns = alloc_INSN_LIST (insn, postponed_insns);
3049 /* When processing REG_NOTES look at the list of
3050 replacements done on the insn to find the register that X
3054 for (tem = purge_bitfield_addressof_replacements;
3056 tem = XEXP (XEXP (tem, 1), 1))
3057 if (rtx_equal_p (x, XEXP (tem, 0)))
3059 *loc = XEXP (XEXP (tem, 1), 0);
3063 /* See comment for purge_addressof_replacements. */
3064 for (tem = purge_addressof_replacements;
3066 tem = XEXP (XEXP (tem, 1), 1))
3067 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3069 rtx z = XEXP (XEXP (tem, 1), 0);
3071 if (GET_MODE (x) == GET_MODE (z)
3072 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3073 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3076 /* It can happen that the note may speak of things
3077 in a wider (or just different) mode than the
3078 code did. This is especially true of
3081 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3084 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3085 && (GET_MODE_SIZE (GET_MODE (x))
3086 > GET_MODE_SIZE (GET_MODE (z))))
3088 /* This can occur as a result in invalid
3089 pointer casts, e.g. float f; ...
3090 *(long long int *)&f.
3091 ??? We could emit a warning here, but
3092 without a line number that wouldn't be
3094 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3097 z = gen_lowpart (GET_MODE (x), z);
3103 /* When we are processing the REG_NOTES of the last instruction
3104 of a libcall, there will be typically no replacements
3105 for that insn; the replacements happened before, piecemeal
3106 fashion. OTOH we are not interested in the details of
3107 this for the REG_EQUAL note, we want to know the big picture,
3108 which can be succinctly described with a simple SUBREG.
3109 Note that removing the REG_EQUAL note is not an option
3110 on the last insn of a libcall, so we must do a replacement. */
3112 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
3114 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
3115 [0 S8 A32]), which can be expressed with a simple
3117 if ((GET_MODE_SIZE (GET_MODE (x))
3118 <= GET_MODE_SIZE (GET_MODE (sub)))
3119 /* Again, invalid pointer casts (as in
3120 compile/990203-1.c) can require paradoxical
3122 || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3123 && (GET_MODE_SIZE (GET_MODE (x))
3124 > GET_MODE_SIZE (GET_MODE (sub)))
3127 *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
3130 /* ??? Are there other cases we should handle? */
3132 /* Sometimes we may not be able to find the replacement. For
3133 example when the original insn was a MEM in a wider mode,
3134 and the note is part of a sign extension of a narrowed
3135 version of that MEM. Gcc testcase compile/990829-1.c can
3136 generate an example of this situation. Rather than complain
3137 we return false, which will prompt our caller to remove the
3142 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3143 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3145 /* Do not frob unchanging MEMs. If a later reference forces the
3146 pseudo to the stack, we can wind up with multiple writes to
3147 an unchanging memory, which is invalid. */
3148 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3151 /* Don't even consider working with paradoxical subregs,
3152 or the moral equivalent seen here. */
3153 else if (size_x <= size_sub
3154 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3156 /* Do a bitfield insertion to mirror what would happen
3163 rtx p = PREV_INSN (insn);
3166 val = gen_reg_rtx (GET_MODE (x));
3167 if (! validate_change (insn, loc, val, 0))
3169 /* Discard the current sequence and put the
3170 ADDRESSOF on stack. */
3176 emit_insn_before (seq, insn);
3177 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3181 store_bit_field (sub, size_x, 0, GET_MODE (x),
3182 val, GET_MODE_SIZE (GET_MODE (sub)));
3184 /* Make sure to unshare any shared rtl that store_bit_field
3185 might have created. */
3186 unshare_all_rtl_again (get_insns ());
3190 p = emit_insn_after (seq, insn);
3191 if (NEXT_INSN (insn))
3192 compute_insns_for_mem (NEXT_INSN (insn),
3193 p ? NEXT_INSN (p) : NULL_RTX,
3198 rtx p = PREV_INSN (insn);
3201 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3202 GET_MODE (x), GET_MODE (x),
3203 GET_MODE_SIZE (GET_MODE (sub)));
3205 if (! validate_change (insn, loc, val, 0))
3207 /* Discard the current sequence and put the
3208 ADDRESSOF on stack. */
3215 emit_insn_before (seq, insn);
3216 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3220 /* Remember the replacement so that the same one can be done
3221 on the REG_NOTES. */
3222 purge_bitfield_addressof_replacements
3223 = gen_rtx_EXPR_LIST (VOIDmode, x,
3226 purge_bitfield_addressof_replacements));
3228 /* We replaced with a reg -- all done. */
3233 else if (validate_change (insn, loc, sub, 0))
3235 /* Remember the replacement so that the same one can be done
3236 on the REG_NOTES. */
3237 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3241 for (tem = purge_addressof_replacements;
3243 tem = XEXP (XEXP (tem, 1), 1))
3244 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3246 XEXP (XEXP (tem, 1), 0) = sub;
3249 purge_addressof_replacements
3250 = gen_rtx_EXPR_LIST (VOIDmode, XEXP (x, 0),
3251 gen_rtx_EXPR_LIST (VOIDmode, sub,
3252 purge_addressof_replacements));
3260 /* Scan all subexpressions. */
3261 fmt = GET_RTX_FORMAT (code);
3262 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3265 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0,
3267 else if (*fmt == 'E')
3268 for (j = 0; j < XVECLEN (x, i); j++)
3269 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0,
3276 /* Return a hash value for K, a REG. */
3279 insns_for_mem_hash (const void *k)
3281 /* Use the address of the key for the hash value. */
3282 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3283 return htab_hash_pointer (m->key);
3286 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3289 insns_for_mem_comp (const void *k1, const void *k2)
3291 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3292 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3293 return m1->key == m2->key;
3296 struct insns_for_mem_walk_info
3298 /* The hash table that we are using to record which INSNs use which
3302 /* The INSN we are currently processing. */
3305 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3306 to find the insns that use the REGs in the ADDRESSOFs. */
3310 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3311 that might be used in an ADDRESSOF expression, record this INSN in
3312 the hash table given by DATA (which is really a pointer to an
3313 insns_for_mem_walk_info structure). */
3316 insns_for_mem_walk (rtx *r, void *data)
3318 struct insns_for_mem_walk_info *ifmwi
3319 = (struct insns_for_mem_walk_info *) data;
3320 struct insns_for_mem_entry tmp;
3321 tmp.insns = NULL_RTX;
3323 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3324 && GET_CODE (XEXP (*r, 0)) == REG)
3327 tmp.key = XEXP (*r, 0);
3328 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3331 *e = ggc_alloc (sizeof (tmp));
3332 memcpy (*e, &tmp, sizeof (tmp));
3335 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3337 struct insns_for_mem_entry *ifme;
3339 ifme = htab_find (ifmwi->ht, &tmp);
3341 /* If we have not already recorded this INSN, do so now. Since
3342 we process the INSNs in order, we know that if we have
3343 recorded it it must be at the front of the list. */
3344 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3345 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3352 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3353 which REGs in HT. */
3356 compute_insns_for_mem (rtx insns, rtx last_insn, htab_t ht)
3359 struct insns_for_mem_walk_info ifmwi;
3362 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3363 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3367 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3371 /* Helper function for purge_addressof called through for_each_rtx.
3372 Returns true iff the rtl is an ADDRESSOF. */
3375 is_addressof (rtx *rtl, void *data ATTRIBUTE_UNUSED)
3377 return GET_CODE (*rtl) == ADDRESSOF;
3380 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3381 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3385 purge_addressof (rtx insns)
3390 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3391 requires a fixup pass over the instruction stream to correct
3392 INSNs that depended on the REG being a REG, and not a MEM. But,
3393 these fixup passes are slow. Furthermore, most MEMs are not
3394 mentioned in very many instructions. So, we speed up the process
3395 by pre-calculating which REGs occur in which INSNs; that allows
3396 us to perform the fixup passes much more quickly. */
3397 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3398 compute_insns_for_mem (insns, NULL_RTX, ht);
3400 postponed_insns = NULL;
3402 for (insn = insns; insn; insn = NEXT_INSN (insn))
3405 if (! purge_addressof_1 (&PATTERN (insn), insn,
3406 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht))
3407 /* If we could not replace the ADDRESSOFs in the insn,
3408 something is wrong. */
3411 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht))
3413 /* If we could not replace the ADDRESSOFs in the insn's notes,
3414 we can just remove the offending notes instead. */
3417 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3419 /* If we find a REG_RETVAL note then the insn is a libcall.
3420 Such insns must have REG_EQUAL notes as well, in order
3421 for later passes of the compiler to work. So it is not
3422 safe to delete the notes here, and instead we abort. */
3423 if (REG_NOTE_KIND (note) == REG_RETVAL)
3425 if (for_each_rtx (¬e, is_addressof, NULL))
3426 remove_note (insn, note);
3431 /* Process the postponed insns. */
3432 while (postponed_insns)
3434 insn = XEXP (postponed_insns, 0);
3435 tmp = postponed_insns;
3436 postponed_insns = XEXP (postponed_insns, 1);
3437 free_INSN_LIST_node (tmp);
3439 if (! purge_addressof_1 (&PATTERN (insn), insn,
3440 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht))
3445 purge_bitfield_addressof_replacements = 0;
3446 purge_addressof_replacements = 0;
3448 /* REGs are shared. purge_addressof will destructively replace a REG
3449 with a MEM, which creates shared MEMs.
3451 Unfortunately, the children of put_reg_into_stack assume that MEMs
3452 referring to the same stack slot are shared (fixup_var_refs and
3453 the associated hash table code).
3455 So, we have to do another unsharing pass after we have flushed any
3456 REGs that had their address taken into the stack.
3458 It may be worth tracking whether or not we converted any REGs into
3459 MEMs to avoid this overhead when it is not needed. */
3460 unshare_all_rtl_again (get_insns ());
3463 /* Convert a SET of a hard subreg to a set of the appropriate hard
3464 register. A subroutine of purge_hard_subreg_sets. */
3467 purge_single_hard_subreg_set (rtx pattern)
3469 rtx reg = SET_DEST (pattern);
3470 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3473 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3474 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3476 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3477 GET_MODE (SUBREG_REG (reg)),
3480 reg = SUBREG_REG (reg);
3484 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3486 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3487 SET_DEST (pattern) = reg;
3491 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3492 only such SETs that we expect to see are those left in because
3493 integrate can't handle sets of parts of a return value register.
3495 We don't use alter_subreg because we only want to eliminate subregs
3496 of hard registers. */
3499 purge_hard_subreg_sets (rtx insn)
3501 for (; insn; insn = NEXT_INSN (insn))
3505 rtx pattern = PATTERN (insn);
3506 switch (GET_CODE (pattern))
3509 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3510 purge_single_hard_subreg_set (pattern);
3515 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3517 rtx inner_pattern = XVECEXP (pattern, 0, j);
3518 if (GET_CODE (inner_pattern) == SET
3519 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3520 purge_single_hard_subreg_set (inner_pattern);
3531 /* Pass through the INSNS of function FNDECL and convert virtual register
3532 references to hard register references. */
3535 instantiate_virtual_regs (tree fndecl, rtx insns)
3540 /* Compute the offsets to use for this function. */
3541 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3542 var_offset = STARTING_FRAME_OFFSET;
3543 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3544 out_arg_offset = STACK_POINTER_OFFSET;
3545 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3547 /* Scan all variables and parameters of this function. For each that is
3548 in memory, instantiate all virtual registers if the result is a valid
3549 address. If not, we do it later. That will handle most uses of virtual
3550 regs on many machines. */
3551 instantiate_decls (fndecl, 1);
3553 /* Initialize recognition, indicating that volatile is OK. */
3556 /* Scan through all the insns, instantiating every virtual register still
3558 for (insn = insns; insn; insn = NEXT_INSN (insn))
3559 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3560 || GET_CODE (insn) == CALL_INSN)
3562 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3563 if (INSN_DELETED_P (insn))
3565 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3566 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3567 if (GET_CODE (insn) == CALL_INSN)
3568 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3571 /* Past this point all ASM statements should match. Verify that
3572 to avoid failures later in the compilation process. */
3573 if (asm_noperands (PATTERN (insn)) >= 0
3574 && ! check_asm_operands (PATTERN (insn)))
3575 instantiate_virtual_regs_lossage (insn);
3578 /* Instantiate the stack slots for the parm registers, for later use in
3579 addressof elimination. */
3580 for (i = 0; i < max_parm_reg; ++i)
3581 if (parm_reg_stack_loc[i])
3582 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3584 /* Now instantiate the remaining register equivalences for debugging info.
3585 These will not be valid addresses. */
3586 instantiate_decls (fndecl, 0);
3588 /* Indicate that, from now on, assign_stack_local should use
3589 frame_pointer_rtx. */
3590 virtuals_instantiated = 1;
3593 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3594 all virtual registers in their DECL_RTL's.
3596 If VALID_ONLY, do this only if the resulting address is still valid.
3597 Otherwise, always do it. */
3600 instantiate_decls (tree fndecl, int valid_only)
3604 /* Process all parameters of the function. */
3605 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3607 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3608 HOST_WIDE_INT size_rtl;
3610 instantiate_decl (DECL_RTL (decl), size, valid_only);
3612 /* If the parameter was promoted, then the incoming RTL mode may be
3613 larger than the declared type size. We must use the larger of
3615 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3616 size = MAX (size_rtl, size);
3617 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3620 /* Now process all variables defined in the function or its subblocks. */
3621 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3624 /* Subroutine of instantiate_decls: Process all decls in the given
3625 BLOCK node and all its subblocks. */
3628 instantiate_decls_1 (tree let, int valid_only)
3632 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3633 if (DECL_RTL_SET_P (t))
3634 instantiate_decl (DECL_RTL (t),
3635 int_size_in_bytes (TREE_TYPE (t)),
3638 /* Process all subblocks. */
3639 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3640 instantiate_decls_1 (t, valid_only);
3643 /* Subroutine of the preceding procedures: Given RTL representing a
3644 decl and the size of the object, do any instantiation required.
3646 If VALID_ONLY is nonzero, it means that the RTL should only be
3647 changed if the new address is valid. */
3650 instantiate_decl (rtx x, HOST_WIDE_INT size, int valid_only)
3652 enum machine_mode mode;
3655 /* If this is not a MEM, no need to do anything. Similarly if the
3656 address is a constant or a register that is not a virtual register. */
3658 if (x == 0 || GET_CODE (x) != MEM)
3662 if (CONSTANT_P (addr)
3663 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3664 || (GET_CODE (addr) == REG
3665 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3666 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3669 /* If we should only do this if the address is valid, copy the address.
3670 We need to do this so we can undo any changes that might make the
3671 address invalid. This copy is unfortunate, but probably can't be
3675 addr = copy_rtx (addr);
3677 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3679 if (valid_only && size >= 0)
3681 unsigned HOST_WIDE_INT decl_size = size;
3683 /* Now verify that the resulting address is valid for every integer or
3684 floating-point mode up to and including SIZE bytes long. We do this
3685 since the object might be accessed in any mode and frame addresses
3688 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3689 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3690 mode = GET_MODE_WIDER_MODE (mode))
3691 if (! memory_address_p (mode, addr))
3694 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3695 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3696 mode = GET_MODE_WIDER_MODE (mode))
3697 if (! memory_address_p (mode, addr))
3701 /* Put back the address now that we have updated it and we either know
3702 it is valid or we don't care whether it is valid. */
3707 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3708 is a virtual register, return the equivalent hard register and set the
3709 offset indirectly through the pointer. Otherwise, return 0. */
3712 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
3715 HOST_WIDE_INT offset;
3717 if (x == virtual_incoming_args_rtx)
3718 new = arg_pointer_rtx, offset = in_arg_offset;
3719 else if (x == virtual_stack_vars_rtx)
3720 new = frame_pointer_rtx, offset = var_offset;
3721 else if (x == virtual_stack_dynamic_rtx)
3722 new = stack_pointer_rtx, offset = dynamic_offset;
3723 else if (x == virtual_outgoing_args_rtx)
3724 new = stack_pointer_rtx, offset = out_arg_offset;
3725 else if (x == virtual_cfa_rtx)
3726 new = arg_pointer_rtx, offset = cfa_offset;
3735 /* Called when instantiate_virtual_regs has failed to update the instruction.
3736 Usually this means that non-matching instruction has been emit, however for
3737 asm statements it may be the problem in the constraints. */
3739 instantiate_virtual_regs_lossage (rtx insn)
3741 if (asm_noperands (PATTERN (insn)) >= 0)
3743 error_for_asm (insn, "impossible constraint in `asm'");
3749 /* Given a pointer to a piece of rtx and an optional pointer to the
3750 containing object, instantiate any virtual registers present in it.
3752 If EXTRA_INSNS, we always do the replacement and generate
3753 any extra insns before OBJECT. If it zero, we do nothing if replacement
3756 Return 1 if we either had nothing to do or if we were able to do the
3757 needed replacement. Return 0 otherwise; we only return zero if
3758 EXTRA_INSNS is zero.
3760 We first try some simple transformations to avoid the creation of extra
3764 instantiate_virtual_regs_1 (rtx *loc, rtx object, int extra_insns)
3769 HOST_WIDE_INT offset = 0;
3775 /* Re-start here to avoid recursion in common cases. */
3782 /* We may have detected and deleted invalid asm statements. */
3783 if (object && INSN_P (object) && INSN_DELETED_P (object))
3786 code = GET_CODE (x);
3788 /* Check for some special cases. */
3806 /* We are allowed to set the virtual registers. This means that
3807 the actual register should receive the source minus the
3808 appropriate offset. This is used, for example, in the handling
3809 of non-local gotos. */
3810 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3812 rtx src = SET_SRC (x);
3814 /* We are setting the register, not using it, so the relevant
3815 offset is the negative of the offset to use were we using
3818 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3820 /* The only valid sources here are PLUS or REG. Just do
3821 the simplest possible thing to handle them. */
3822 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3824 instantiate_virtual_regs_lossage (object);
3829 if (GET_CODE (src) != REG)
3830 temp = force_operand (src, NULL_RTX);
3833 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3837 emit_insn_before (seq, object);
3840 if (! validate_change (object, &SET_SRC (x), temp, 0)
3842 instantiate_virtual_regs_lossage (object);
3847 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3852 /* Handle special case of virtual register plus constant. */
3853 if (CONSTANT_P (XEXP (x, 1)))
3855 rtx old, new_offset;
3857 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3858 if (GET_CODE (XEXP (x, 0)) == PLUS)
3860 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3862 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3864 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3873 #ifdef POINTERS_EXTEND_UNSIGNED
3874 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3875 we can commute the PLUS and SUBREG because pointers into the
3876 frame are well-behaved. */
3877 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3878 && GET_CODE (XEXP (x, 1)) == CONST_INT
3880 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3882 && validate_change (object, loc,
3883 plus_constant (gen_lowpart (ptr_mode,
3886 + INTVAL (XEXP (x, 1))),
3890 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3892 /* We know the second operand is a constant. Unless the
3893 first operand is a REG (which has been already checked),
3894 it needs to be checked. */
3895 if (GET_CODE (XEXP (x, 0)) != REG)
3903 new_offset = plus_constant (XEXP (x, 1), offset);
3905 /* If the new constant is zero, try to replace the sum with just
3907 if (new_offset == const0_rtx
3908 && validate_change (object, loc, new, 0))
3911 /* Next try to replace the register and new offset.
3912 There are two changes to validate here and we can't assume that
3913 in the case of old offset equals new just changing the register
3914 will yield a valid insn. In the interests of a little efficiency,
3915 however, we only call validate change once (we don't queue up the
3916 changes and then call apply_change_group). */
3920 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3921 : (XEXP (x, 0) = new,
3922 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3930 /* Otherwise copy the new constant into a register and replace
3931 constant with that register. */
3932 temp = gen_reg_rtx (Pmode);
3934 if (validate_change (object, &XEXP (x, 1), temp, 0))
3935 emit_insn_before (gen_move_insn (temp, new_offset), object);
3938 /* If that didn't work, replace this expression with a
3939 register containing the sum. */
3942 new = gen_rtx_PLUS (Pmode, new, new_offset);
3945 temp = force_operand (new, NULL_RTX);
3949 emit_insn_before (seq, object);
3950 if (! validate_change (object, loc, temp, 0)
3951 && ! validate_replace_rtx (x, temp, object))
3953 instantiate_virtual_regs_lossage (object);
3962 /* Fall through to generic two-operand expression case. */
3968 case DIV: case UDIV:
3969 case MOD: case UMOD:
3970 case AND: case IOR: case XOR:
3971 case ROTATERT: case ROTATE:
3972 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3974 case GE: case GT: case GEU: case GTU:
3975 case LE: case LT: case LEU: case LTU:
3976 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3977 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3982 /* Most cases of MEM that convert to valid addresses have already been
3983 handled by our scan of decls. The only special handling we
3984 need here is to make a copy of the rtx to ensure it isn't being
3985 shared if we have to change it to a pseudo.
3987 If the rtx is a simple reference to an address via a virtual register,
3988 it can potentially be shared. In such cases, first try to make it
3989 a valid address, which can also be shared. Otherwise, copy it and
3992 First check for common cases that need no processing. These are
3993 usually due to instantiation already being done on a previous instance
3997 if (CONSTANT_ADDRESS_P (temp)
3998 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3999 || temp == arg_pointer_rtx
4001 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4002 || temp == hard_frame_pointer_rtx
4004 || temp == frame_pointer_rtx)
4007 if (GET_CODE (temp) == PLUS
4008 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4009 && (XEXP (temp, 0) == frame_pointer_rtx
4010 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4011 || XEXP (temp, 0) == hard_frame_pointer_rtx
4013 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4014 || XEXP (temp, 0) == arg_pointer_rtx
4019 if (temp == virtual_stack_vars_rtx
4020 || temp == virtual_incoming_args_rtx
4021 || (GET_CODE (temp) == PLUS
4022 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4023 && (XEXP (temp, 0) == virtual_stack_vars_rtx
4024 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
4026 /* This MEM may be shared. If the substitution can be done without
4027 the need to generate new pseudos, we want to do it in place
4028 so all copies of the shared rtx benefit. The call below will
4029 only make substitutions if the resulting address is still
4032 Note that we cannot pass X as the object in the recursive call
4033 since the insn being processed may not allow all valid
4034 addresses. However, if we were not passed on object, we can
4035 only modify X without copying it if X will have a valid
4038 ??? Also note that this can still lose if OBJECT is an insn that
4039 has less restrictions on an address that some other insn.
4040 In that case, we will modify the shared address. This case
4041 doesn't seem very likely, though. One case where this could
4042 happen is in the case of a USE or CLOBBER reference, but we
4043 take care of that below. */
4045 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4046 object ? object : x, 0))
4049 /* Otherwise make a copy and process that copy. We copy the entire
4050 RTL expression since it might be a PLUS which could also be
4052 *loc = x = copy_rtx (x);
4055 /* Fall through to generic unary operation case. */
4058 case STRICT_LOW_PART:
4060 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4061 case SIGN_EXTEND: case ZERO_EXTEND:
4062 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4063 case FLOAT: case FIX:
4064 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4069 case POPCOUNT: case PARITY:
4070 /* These case either have just one operand or we know that we need not
4071 check the rest of the operands. */
4077 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4078 go ahead and make the invalid one, but do it to a copy. For a REG,
4079 just make the recursive call, since there's no chance of a problem. */
4081 if ((GET_CODE (XEXP (x, 0)) == MEM
4082 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4084 || (GET_CODE (XEXP (x, 0)) == REG
4085 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4088 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4093 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4094 in front of this insn and substitute the temporary. */
4095 if ((new = instantiate_new_reg (x, &offset)) != 0)
4097 temp = plus_constant (new, offset);
4098 if (!validate_change (object, loc, temp, 0))
4104 temp = force_operand (temp, NULL_RTX);
4108 emit_insn_before (seq, object);
4109 if (! validate_change (object, loc, temp, 0)
4110 && ! validate_replace_rtx (x, temp, object))
4111 instantiate_virtual_regs_lossage (object);
4118 if (GET_CODE (XEXP (x, 0)) == REG)
4121 else if (GET_CODE (XEXP (x, 0)) == MEM)
4123 /* If we have a (addressof (mem ..)), do any instantiation inside
4124 since we know we'll be making the inside valid when we finally
4125 remove the ADDRESSOF. */
4126 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4135 /* Scan all subexpressions. */
4136 fmt = GET_RTX_FORMAT (code);
4137 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4140 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4143 else if (*fmt == 'E')
4144 for (j = 0; j < XVECLEN (x, i); j++)
4145 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4152 /* Optimization: assuming this function does not receive nonlocal gotos,
4153 delete the handlers for such, as well as the insns to establish
4154 and disestablish them. */
4157 delete_handlers (void)
4160 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4162 /* Delete the handler by turning off the flag that would
4163 prevent jump_optimize from deleting it.
4164 Also permit deletion of the nonlocal labels themselves
4165 if nothing local refers to them. */
4166 if (GET_CODE (insn) == CODE_LABEL)
4170 LABEL_PRESERVE_P (insn) = 0;
4172 /* Remove it from the nonlocal_label list, to avoid confusing
4174 for (t = nonlocal_labels, last_t = 0; t;
4175 last_t = t, t = TREE_CHAIN (t))
4176 if (DECL_RTL (TREE_VALUE (t)) == insn)
4181 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4183 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4186 if (GET_CODE (insn) == INSN)
4190 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4191 if (reg_mentioned_p (t, PATTERN (insn)))
4197 || (nonlocal_goto_stack_level != 0
4198 && reg_mentioned_p (nonlocal_goto_stack_level,
4200 delete_related_insns (insn);
4205 /* Return the first insn following those generated by `assign_parms'. */
4208 get_first_nonparm_insn (void)
4211 return NEXT_INSN (last_parm_insn);
4212 return get_insns ();
4215 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4216 This means a type for which function calls must pass an address to the
4217 function or get an address back from the function.
4218 EXP may be a type node or an expression (whose type is tested). */
4221 aggregate_value_p (tree exp, tree fntype)
4223 int i, regno, nregs;
4226 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4229 switch (TREE_CODE (fntype))
4232 fntype = get_callee_fndecl (fntype);
4233 fntype = fntype ? TREE_TYPE (fntype) : 0;
4236 fntype = TREE_TYPE (fntype);
4241 case IDENTIFIER_NODE:
4245 /* We don't expect other rtl types here. */
4249 if (TREE_CODE (type) == VOID_TYPE)
4251 if (targetm.calls.return_in_memory (type, fntype))
4253 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4254 and thus can't be returned in registers. */
4255 if (TREE_ADDRESSABLE (type))
4257 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4259 /* Make sure we have suitable call-clobbered regs to return
4260 the value in; if not, we must return it in memory. */
4261 reg = hard_function_value (type, 0, 0);
4263 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4265 if (GET_CODE (reg) != REG)
4268 regno = REGNO (reg);
4269 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
4270 for (i = 0; i < nregs; i++)
4271 if (! call_used_regs[regno + i])
4276 /* Assign RTL expressions to the function's parameters.
4277 This may involve copying them into registers and using
4278 those registers as the RTL for them. */
4281 assign_parms (tree fndecl)
4284 CUMULATIVE_ARGS args_so_far;
4285 /* Total space needed so far for args on the stack,
4286 given as a constant and a tree-expression. */
4287 struct args_size stack_args_size;
4288 tree fntype = TREE_TYPE (fndecl);
4289 tree fnargs = DECL_ARGUMENTS (fndecl), orig_fnargs;
4290 /* This is used for the arg pointer when referring to stack args. */
4291 rtx internal_arg_pointer;
4292 /* This is a dummy PARM_DECL that we used for the function result if
4293 the function returns a structure. */
4294 tree function_result_decl = 0;
4295 int varargs_setup = 0;
4296 int reg_parm_stack_space ATTRIBUTE_UNUSED = 0;
4297 rtx conversion_insns = 0;
4299 /* Nonzero if function takes extra anonymous args.
4300 This means the last named arg must be on the stack
4301 right before the anonymous ones. */
4303 = (TYPE_ARG_TYPES (fntype) != 0
4304 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4305 != void_type_node));
4307 current_function_stdarg = stdarg;
4309 /* If the reg that the virtual arg pointer will be translated into is
4310 not a fixed reg or is the stack pointer, make a copy of the virtual
4311 arg pointer, and address parms via the copy. The frame pointer is
4312 considered fixed even though it is not marked as such.
4314 The second time through, simply use ap to avoid generating rtx. */
4316 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4317 || ! (fixed_regs[ARG_POINTER_REGNUM]
4318 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4319 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4321 internal_arg_pointer = virtual_incoming_args_rtx;
4322 current_function_internal_arg_pointer = internal_arg_pointer;
4324 stack_args_size.constant = 0;
4325 stack_args_size.var = 0;
4327 /* If struct value address is treated as the first argument, make it so. */
4328 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
4329 && ! current_function_returns_pcc_struct
4330 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
4332 tree type = build_pointer_type (TREE_TYPE (fntype));
4334 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4336 DECL_ARG_TYPE (function_result_decl) = type;
4337 TREE_CHAIN (function_result_decl) = fnargs;
4338 fnargs = function_result_decl;
4341 orig_fnargs = fnargs;
4343 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4344 parm_reg_stack_loc = ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4346 if (SPLIT_COMPLEX_ARGS)
4347 fnargs = split_complex_args (fnargs);
4349 #ifdef REG_PARM_STACK_SPACE
4350 #ifdef MAYBE_REG_PARM_STACK_SPACE
4351 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4353 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4357 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4358 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4360 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl, -1);
4363 /* We haven't yet found an argument that we must push and pretend the
4365 current_function_pretend_args_size = 0;
4367 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4371 enum machine_mode promoted_mode, passed_mode;
4372 enum machine_mode nominal_mode, promoted_nominal_mode;
4374 struct locate_and_pad_arg_data locate;
4375 int passed_pointer = 0;
4376 int did_conversion = 0;
4377 tree passed_type = DECL_ARG_TYPE (parm);
4378 tree nominal_type = TREE_TYPE (parm);
4379 int last_named = 0, named_arg;
4382 int pretend_bytes = 0;
4383 int loaded_in_reg = 0;
4385 /* Set LAST_NAMED if this is last named arg before last
4391 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4392 if (DECL_NAME (tem))
4398 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4399 most machines, if this is a varargs/stdarg function, then we treat
4400 the last named arg as if it were anonymous too. */
4401 named_arg = (targetm.calls.strict_argument_naming (&args_so_far)
4404 if (TREE_TYPE (parm) == error_mark_node
4405 /* This can happen after weird syntax errors
4406 or if an enum type is defined among the parms. */
4407 || TREE_CODE (parm) != PARM_DECL
4408 || passed_type == NULL)
4410 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4411 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4412 TREE_USED (parm) = 1;
4416 /* Find mode of arg as it is passed, and mode of arg
4417 as it should be during execution of this function. */
4418 passed_mode = TYPE_MODE (passed_type);
4419 nominal_mode = TYPE_MODE (nominal_type);
4421 /* If the parm's mode is VOID, its value doesn't matter,
4422 and avoid the usual things like emit_move_insn that could crash. */
4423 if (nominal_mode == VOIDmode)
4425 SET_DECL_RTL (parm, const0_rtx);
4426 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4430 /* If the parm is to be passed as a transparent union, use the
4431 type of the first field for the tests below. We have already
4432 verified that the modes are the same. */
4433 if (DECL_TRANSPARENT_UNION (parm)
4434 || (TREE_CODE (passed_type) == UNION_TYPE
4435 && TYPE_TRANSPARENT_UNION (passed_type)))
4436 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4438 /* See if this arg was passed by invisible reference. It is if
4439 it is an object whose size depends on the contents of the
4440 object itself or if the machine requires these objects be passed
4443 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type))
4444 || TREE_ADDRESSABLE (passed_type)
4445 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4446 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4447 passed_type, named_arg)
4451 passed_type = nominal_type = build_pointer_type (passed_type);
4453 passed_mode = nominal_mode = Pmode;
4455 /* See if the frontend wants to pass this by invisible reference. */
4456 else if (passed_type != nominal_type
4457 && POINTER_TYPE_P (passed_type)
4458 && TREE_TYPE (passed_type) == nominal_type)
4460 nominal_type = passed_type;
4462 passed_mode = nominal_mode = Pmode;
4465 promoted_mode = passed_mode;
4467 if (targetm.calls.promote_function_args (TREE_TYPE (fndecl)))
4469 /* Compute the mode in which the arg is actually extended to. */
4470 unsignedp = TREE_UNSIGNED (passed_type);
4471 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4474 /* Let machine desc say which reg (if any) the parm arrives in.
4475 0 means it arrives on the stack. */
4476 #ifdef FUNCTION_INCOMING_ARG
4477 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4478 passed_type, named_arg);
4480 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4481 passed_type, named_arg);
4484 if (entry_parm == 0)
4485 promoted_mode = passed_mode;
4487 /* If this is the last named parameter, do any required setup for
4488 varargs or stdargs. We need to know about the case of this being an
4489 addressable type, in which case we skip the registers it
4490 would have arrived in.
4492 For stdargs, LAST_NAMED will be set for two parameters, the one that
4493 is actually the last named, and the dummy parameter. We only
4494 want to do this action once.
4496 Also, indicate when RTL generation is to be suppressed. */
4497 if (last_named && !varargs_setup)
4499 int varargs_pretend_bytes = 0;
4500 targetm.calls.setup_incoming_varargs (&args_so_far, promoted_mode,
4502 &varargs_pretend_bytes, 0);
4505 /* If the back-end has requested extra stack space, record how
4506 much is needed. Do not change pretend_args_size otherwise
4507 since it may be nonzero from an earlier partial argument. */
4508 if (varargs_pretend_bytes > 0)
4509 current_function_pretend_args_size = varargs_pretend_bytes;
4512 /* Determine parm's home in the stack,
4513 in case it arrives in the stack or we should pretend it did.
4515 Compute the stack position and rtx where the argument arrives
4518 There is one complexity here: If this was a parameter that would
4519 have been passed in registers, but wasn't only because it is
4520 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4521 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4522 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4523 0 as it was the previous time. */
4524 in_regs = entry_parm != 0;
4525 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4528 if (!in_regs && !named_arg)
4531 targetm.calls.pretend_outgoing_varargs_named (&args_so_far);
4534 #ifdef FUNCTION_INCOMING_ARG
4535 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4537 pretend_named) != 0;
4539 in_regs = FUNCTION_ARG (args_so_far, promoted_mode,
4541 pretend_named) != 0;
4546 /* If this parameter was passed both in registers and in the stack,
4547 use the copy on the stack. */
4548 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4551 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4554 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4555 passed_type, named_arg);
4557 #ifndef MAYBE_REG_PARM_STACK_SPACE
4558 /* The caller might already have allocated stack space
4559 for the register parameters. */
4560 && reg_parm_stack_space == 0
4564 /* Part of this argument is passed in registers and part
4565 is passed on the stack. Ask the prologue code to extend
4566 the stack part so that we can recreate the full value.
4568 PRETEND_BYTES is the size of the registers we need to store.
4569 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
4570 stack space that the prologue should allocate.
4572 Internally, gcc assumes that the argument pointer is
4573 aligned to STACK_BOUNDARY bits. This is used both for
4574 alignment optimizations (see init_emit) and to locate
4575 arguments that are aligned to more than PARM_BOUNDARY
4576 bits. We must preserve this invariant by rounding
4577 CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to a stack
4579 pretend_bytes = partial * UNITS_PER_WORD;
4580 current_function_pretend_args_size
4581 = CEIL_ROUND (pretend_bytes, STACK_BYTES);
4583 /* If PRETEND_BYTES != CURRENT_FUNCTION_PRETEND_ARGS_SIZE,
4584 insert the padding before the start of the first pretend
4586 stack_args_size.constant
4587 = (current_function_pretend_args_size - pretend_bytes);
4592 memset (&locate, 0, sizeof (locate));
4593 locate_and_pad_parm (promoted_mode, passed_type, in_regs,
4594 entry_parm ? partial : 0, fndecl,
4595 &stack_args_size, &locate);
4600 /* If we're passing this arg using a reg, make its stack home
4601 the aligned stack slot. */
4603 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset);
4605 offset_rtx = ARGS_SIZE_RTX (locate.offset);
4607 if (offset_rtx == const0_rtx)
4608 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4610 stack_parm = gen_rtx_MEM (promoted_mode,
4611 gen_rtx_PLUS (Pmode,
4612 internal_arg_pointer,
4615 set_mem_attributes (stack_parm, parm, 1);
4616 if (entry_parm && MEM_ATTRS (stack_parm)->align < PARM_BOUNDARY)
4617 set_mem_align (stack_parm, PARM_BOUNDARY);
4619 /* Set also REG_ATTRS if parameter was passed in a register. */
4621 set_reg_attrs_for_parm (entry_parm, stack_parm);
4624 /* If this parm was passed part in regs and part in memory,
4625 pretend it arrived entirely in memory
4626 by pushing the register-part onto the stack.
4628 In the special case of a DImode or DFmode that is split,
4629 we could put it together in a pseudoreg directly,
4630 but for now that's not worth bothering with. */
4634 /* Handle calls that pass values in multiple non-contiguous
4635 locations. The Irix 6 ABI has examples of this. */
4636 if (GET_CODE (entry_parm) == PARALLEL)
4637 emit_group_store (validize_mem (stack_parm), entry_parm,
4639 int_size_in_bytes (TREE_TYPE (parm)));
4642 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
4645 entry_parm = stack_parm;
4648 /* If we didn't decide this parm came in a register,
4649 by default it came on the stack. */
4650 if (entry_parm == 0)
4651 entry_parm = stack_parm;
4653 /* Record permanently how this parm was passed. */
4654 set_decl_incoming_rtl (parm, entry_parm);
4656 /* If there is actually space on the stack for this parm,
4657 count it in stack_args_size; otherwise set stack_parm to 0
4658 to indicate there is no preallocated stack slot for the parm. */
4660 if (entry_parm == stack_parm
4661 || (GET_CODE (entry_parm) == PARALLEL
4662 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4663 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4664 /* On some machines, even if a parm value arrives in a register
4665 there is still an (uninitialized) stack slot allocated for it.
4667 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4668 whether this parameter already has a stack slot allocated,
4669 because an arg block exists only if current_function_args_size
4670 is larger than some threshold, and we haven't calculated that
4671 yet. So, for now, we just assume that stack slots never exist
4673 || REG_PARM_STACK_SPACE (fndecl) > 0
4677 stack_args_size.constant += pretend_bytes + locate.size.constant;
4678 if (locate.size.var)
4679 ADD_PARM_SIZE (stack_args_size, locate.size.var);
4682 /* No stack slot was pushed for this parm. */
4685 /* Update info on where next arg arrives in registers. */
4687 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4688 passed_type, named_arg);
4690 /* If we can't trust the parm stack slot to be aligned enough
4691 for its ultimate type, don't use that slot after entry.
4692 We'll make another stack slot, if we need one. */
4694 unsigned int thisparm_boundary
4695 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4697 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4701 /* If parm was passed in memory, and we need to convert it on entry,
4702 don't store it back in that same slot. */
4703 if (entry_parm == stack_parm
4704 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4707 /* When an argument is passed in multiple locations, we can't
4708 make use of this information, but we can save some copying if
4709 the whole argument is passed in a single register. */
4710 if (GET_CODE (entry_parm) == PARALLEL
4711 && nominal_mode != BLKmode && passed_mode != BLKmode)
4713 int i, len = XVECLEN (entry_parm, 0);
4715 for (i = 0; i < len; i++)
4716 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4717 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4718 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4720 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4722 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4723 set_decl_incoming_rtl (parm, entry_parm);
4728 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4729 in the mode in which it arrives.
4730 STACK_PARM is an RTX for a stack slot where the parameter can live
4731 during the function (in case we want to put it there).
4732 STACK_PARM is 0 if no stack slot was pushed for it.
4734 Now output code if necessary to convert ENTRY_PARM to
4735 the type in which this function declares it,
4736 and store that result in an appropriate place,
4737 which may be a pseudo reg, may be STACK_PARM,
4738 or may be a local stack slot if STACK_PARM is 0.
4740 Set DECL_RTL to that place. */
4742 if (GET_CODE (entry_parm) == PARALLEL && nominal_mode != BLKmode
4743 && XVECLEN (entry_parm, 0) > 1)
4745 /* Reconstitute objects the size of a register or larger using
4746 register operations instead of the stack. */
4747 rtx parmreg = gen_reg_rtx (nominal_mode);
4749 if (REG_P (parmreg))
4751 unsigned int regno = REGNO (parmreg);
4753 emit_group_store (parmreg, entry_parm, TREE_TYPE (parm),
4754 int_size_in_bytes (TREE_TYPE (parm)));
4755 SET_DECL_RTL (parm, parmreg);
4758 if (regno >= max_parm_reg)
4761 int old_max_parm_reg = max_parm_reg;
4763 /* It's slow to expand this one register at a time,
4764 but it's also rare and we need max_parm_reg to be
4765 precisely correct. */
4766 max_parm_reg = regno + 1;
4767 new = ggc_realloc (parm_reg_stack_loc,
4768 max_parm_reg * sizeof (rtx));
4769 memset (new + old_max_parm_reg, 0,
4770 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4771 parm_reg_stack_loc = new;
4772 parm_reg_stack_loc[regno] = stack_parm;
4777 if (nominal_mode == BLKmode
4778 #ifdef BLOCK_REG_PADDING
4779 || (locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward)
4780 && GET_MODE_SIZE (promoted_mode) < UNITS_PER_WORD)
4782 || GET_CODE (entry_parm) == PARALLEL)
4784 /* If a BLKmode arrives in registers, copy it to a stack slot.
4785 Handle calls that pass values in multiple non-contiguous
4786 locations. The Irix 6 ABI has examples of this. */
4787 if (GET_CODE (entry_parm) == REG
4788 || (GET_CODE (entry_parm) == PARALLEL
4789 && (!loaded_in_reg || !optimize)))
4791 int size = int_size_in_bytes (TREE_TYPE (parm));
4792 int size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
4795 /* Note that we will be storing an integral number of words.
4796 So we have to be careful to ensure that we allocate an
4797 integral number of words. We do this below in the
4798 assign_stack_local if space was not allocated in the argument
4799 list. If it was, this will not work if PARM_BOUNDARY is not
4800 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4801 if it becomes a problem. Exception is when BLKmode arrives
4802 with arguments not conforming to word_mode. */
4804 if (stack_parm == 0)
4806 stack_parm = assign_stack_local (BLKmode, size_stored, 0);
4807 PUT_MODE (stack_parm, GET_MODE (entry_parm));
4808 set_mem_attributes (stack_parm, parm, 1);
4810 else if (GET_CODE (entry_parm) == PARALLEL
4811 && GET_MODE(entry_parm) == BLKmode)
4813 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4816 mem = validize_mem (stack_parm);
4818 /* Handle calls that pass values in multiple non-contiguous
4819 locations. The Irix 6 ABI has examples of this. */
4820 if (GET_CODE (entry_parm) == PARALLEL)
4821 emit_group_store (mem, entry_parm, TREE_TYPE (parm), size);
4826 /* If SIZE is that of a mode no bigger than a word, just use
4827 that mode's store operation. */
4828 else if (size <= UNITS_PER_WORD)
4830 enum machine_mode mode
4831 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
4834 #ifdef BLOCK_REG_PADDING
4835 && (size == UNITS_PER_WORD
4836 || (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4837 != (BYTES_BIG_ENDIAN ? upward : downward)))
4841 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
4842 emit_move_insn (change_address (mem, mode, 0), reg);
4845 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
4846 machine must be aligned to the left before storing
4847 to memory. Note that the previous test doesn't
4848 handle all cases (e.g. SIZE == 3). */
4849 else if (size != UNITS_PER_WORD
4850 #ifdef BLOCK_REG_PADDING
4851 && (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4859 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4860 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
4862 x = expand_binop (word_mode, ashl_optab, reg,
4863 GEN_INT (by), 0, 1, OPTAB_WIDEN);
4864 tem = change_address (mem, word_mode, 0);
4865 emit_move_insn (tem, x);
4868 move_block_from_reg (REGNO (entry_parm), mem,
4869 size_stored / UNITS_PER_WORD);
4872 move_block_from_reg (REGNO (entry_parm), mem,
4873 size_stored / UNITS_PER_WORD);
4875 /* If parm is already bound to register pair, don't change
4877 if (! DECL_RTL_SET_P (parm))
4878 SET_DECL_RTL (parm, stack_parm);
4880 else if (! ((! optimize
4881 && ! DECL_REGISTER (parm))
4882 || TREE_SIDE_EFFECTS (parm)
4883 /* If -ffloat-store specified, don't put explicit
4884 float variables into registers. */
4885 || (flag_float_store
4886 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4887 /* Always assign pseudo to structure return or item passed
4888 by invisible reference. */
4889 || passed_pointer || parm == function_result_decl)
4891 /* Store the parm in a pseudoregister during the function, but we
4892 may need to do it in a wider mode. */
4895 unsigned int regno, regnoi = 0, regnor = 0;
4897 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4899 promoted_nominal_mode
4900 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4902 parmreg = gen_reg_rtx (promoted_nominal_mode);
4903 mark_user_reg (parmreg);
4905 /* If this was an item that we received a pointer to, set DECL_RTL
4909 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4911 set_mem_attributes (x, parm, 1);
4912 SET_DECL_RTL (parm, x);
4916 SET_DECL_RTL (parm, parmreg);
4917 maybe_set_unchanging (DECL_RTL (parm), parm);
4920 /* Copy the value into the register. */
4921 if (nominal_mode != passed_mode
4922 || promoted_nominal_mode != promoted_mode)
4925 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4926 mode, by the caller. We now have to convert it to
4927 NOMINAL_MODE, if different. However, PARMREG may be in
4928 a different mode than NOMINAL_MODE if it is being stored
4931 If ENTRY_PARM is a hard register, it might be in a register
4932 not valid for operating in its mode (e.g., an odd-numbered
4933 register for a DFmode). In that case, moves are the only
4934 thing valid, so we can't do a convert from there. This
4935 occurs when the calling sequence allow such misaligned
4938 In addition, the conversion may involve a call, which could
4939 clobber parameters which haven't been copied to pseudo
4940 registers yet. Therefore, we must first copy the parm to
4941 a pseudo reg here, and save the conversion until after all
4942 parameters have been moved. */
4944 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4946 emit_move_insn (tempreg, validize_mem (entry_parm));
4948 push_to_sequence (conversion_insns);
4949 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4951 if (GET_CODE (tempreg) == SUBREG
4952 && GET_MODE (tempreg) == nominal_mode
4953 && GET_CODE (SUBREG_REG (tempreg)) == REG
4954 && nominal_mode == passed_mode
4955 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4956 && GET_MODE_SIZE (GET_MODE (tempreg))
4957 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4959 /* The argument is already sign/zero extended, so note it
4961 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4962 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4965 /* TREE_USED gets set erroneously during expand_assignment. */
4966 save_tree_used = TREE_USED (parm);
4967 expand_assignment (parm,
4968 make_tree (nominal_type, tempreg), 0);
4969 TREE_USED (parm) = save_tree_used;
4970 conversion_insns = get_insns ();
4975 emit_move_insn (parmreg, validize_mem (entry_parm));
4977 /* If we were passed a pointer but the actual value
4978 can safely live in a register, put it in one. */
4979 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4980 /* If by-reference argument was promoted, demote it. */
4981 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4983 && ! DECL_REGISTER (parm))
4984 || TREE_SIDE_EFFECTS (parm)
4985 /* If -ffloat-store specified, don't put explicit
4986 float variables into registers. */
4987 || (flag_float_store
4988 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4990 /* We can't use nominal_mode, because it will have been set to
4991 Pmode above. We must use the actual mode of the parm. */
4992 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4993 mark_user_reg (parmreg);
4994 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4996 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4997 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4998 push_to_sequence (conversion_insns);
4999 emit_move_insn (tempreg, DECL_RTL (parm));
5001 convert_to_mode (GET_MODE (parmreg),
5004 emit_move_insn (parmreg, DECL_RTL (parm));
5005 conversion_insns = get_insns();
5010 emit_move_insn (parmreg, DECL_RTL (parm));
5011 SET_DECL_RTL (parm, parmreg);
5012 /* STACK_PARM is the pointer, not the parm, and PARMREG is
5016 #ifdef FUNCTION_ARG_CALLEE_COPIES
5017 /* If we are passed an arg by reference and it is our responsibility
5018 to make a copy, do it now.
5019 PASSED_TYPE and PASSED mode now refer to the pointer, not the
5020 original argument, so we must recreate them in the call to
5021 FUNCTION_ARG_CALLEE_COPIES. */
5022 /* ??? Later add code to handle the case that if the argument isn't
5023 modified, don't do the copy. */
5025 else if (passed_pointer
5026 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
5027 TYPE_MODE (TREE_TYPE (passed_type)),
5028 TREE_TYPE (passed_type),
5030 && ! TREE_ADDRESSABLE (TREE_TYPE (passed_type)))
5033 tree type = TREE_TYPE (passed_type);
5035 /* This sequence may involve a library call perhaps clobbering
5036 registers that haven't been copied to pseudos yet. */
5038 push_to_sequence (conversion_insns);
5040 if (!COMPLETE_TYPE_P (type)
5041 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5042 /* This is a variable sized object. */
5043 copy = gen_rtx_MEM (BLKmode,
5044 allocate_dynamic_stack_space
5045 (expr_size (parm), NULL_RTX,
5046 TYPE_ALIGN (type)));
5048 copy = assign_stack_temp (TYPE_MODE (type),
5049 int_size_in_bytes (type), 1);
5050 set_mem_attributes (copy, parm, 1);
5052 store_expr (parm, copy, 0);
5053 emit_move_insn (parmreg, XEXP (copy, 0));
5054 conversion_insns = get_insns ();
5058 #endif /* FUNCTION_ARG_CALLEE_COPIES */
5060 /* In any case, record the parm's desired stack location
5061 in case we later discover it must live in the stack.
5063 If it is a COMPLEX value, store the stack location for both
5066 if (GET_CODE (parmreg) == CONCAT)
5067 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
5069 regno = REGNO (parmreg);
5071 if (regno >= max_parm_reg)
5074 int old_max_parm_reg = max_parm_reg;
5076 /* It's slow to expand this one register at a time,
5077 but it's also rare and we need max_parm_reg to be
5078 precisely correct. */
5079 max_parm_reg = regno + 1;
5080 new = ggc_realloc (parm_reg_stack_loc,
5081 max_parm_reg * sizeof (rtx));
5082 memset (new + old_max_parm_reg, 0,
5083 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
5084 parm_reg_stack_loc = new;
5087 if (GET_CODE (parmreg) == CONCAT)
5089 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
5091 regnor = REGNO (gen_realpart (submode, parmreg));
5092 regnoi = REGNO (gen_imagpart (submode, parmreg));
5094 if (stack_parm != 0)
5096 parm_reg_stack_loc[regnor]
5097 = gen_realpart (submode, stack_parm);
5098 parm_reg_stack_loc[regnoi]
5099 = gen_imagpart (submode, stack_parm);
5103 parm_reg_stack_loc[regnor] = 0;
5104 parm_reg_stack_loc[regnoi] = 0;
5108 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
5110 /* Mark the register as eliminable if we did no conversion
5111 and it was copied from memory at a fixed offset,
5112 and the arg pointer was not copied to a pseudo-reg.
5113 If the arg pointer is a pseudo reg or the offset formed
5114 an invalid address, such memory-equivalences
5115 as we make here would screw up life analysis for it. */
5116 if (nominal_mode == passed_mode
5119 && GET_CODE (stack_parm) == MEM
5120 && locate.offset.var == 0
5121 && reg_mentioned_p (virtual_incoming_args_rtx,
5122 XEXP (stack_parm, 0)))
5124 rtx linsn = get_last_insn ();
5127 /* Mark complex types separately. */
5128 if (GET_CODE (parmreg) == CONCAT)
5129 /* Scan backwards for the set of the real and
5131 for (sinsn = linsn; sinsn != 0;
5132 sinsn = prev_nonnote_insn (sinsn))
5134 set = single_set (sinsn);
5136 && SET_DEST (set) == regno_reg_rtx [regnoi])
5138 = gen_rtx_EXPR_LIST (REG_EQUIV,
5139 parm_reg_stack_loc[regnoi],
5142 && SET_DEST (set) == regno_reg_rtx [regnor])
5144 = gen_rtx_EXPR_LIST (REG_EQUIV,
5145 parm_reg_stack_loc[regnor],
5148 else if ((set = single_set (linsn)) != 0
5149 && SET_DEST (set) == parmreg)
5151 = gen_rtx_EXPR_LIST (REG_EQUIV,
5152 stack_parm, REG_NOTES (linsn));
5155 /* For pointer data type, suggest pointer register. */
5156 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5157 mark_reg_pointer (parmreg,
5158 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5160 /* If something wants our address, try to use ADDRESSOF. */
5161 if (TREE_ADDRESSABLE (parm))
5163 /* If we end up putting something into the stack,
5164 fixup_var_refs_insns will need to make a pass over
5165 all the instructions. It looks through the pending
5166 sequences -- but it can't see the ones in the
5167 CONVERSION_INSNS, if they're not on the sequence
5168 stack. So, we go back to that sequence, just so that
5169 the fixups will happen. */
5170 push_to_sequence (conversion_insns);
5171 put_var_into_stack (parm, /*rescan=*/true);
5172 conversion_insns = get_insns ();
5178 /* Value must be stored in the stack slot STACK_PARM
5179 during function execution. */
5181 if (promoted_mode != nominal_mode)
5183 /* Conversion is required. */
5184 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5186 emit_move_insn (tempreg, validize_mem (entry_parm));
5188 push_to_sequence (conversion_insns);
5189 entry_parm = convert_to_mode (nominal_mode, tempreg,
5190 TREE_UNSIGNED (TREE_TYPE (parm)));
5192 /* ??? This may need a big-endian conversion on sparc64. */
5193 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5195 conversion_insns = get_insns ();
5200 if (entry_parm != stack_parm)
5202 if (stack_parm == 0)
5205 = assign_stack_local (GET_MODE (entry_parm),
5206 GET_MODE_SIZE (GET_MODE (entry_parm)),
5208 set_mem_attributes (stack_parm, parm, 1);
5211 if (promoted_mode != nominal_mode)
5213 push_to_sequence (conversion_insns);
5214 emit_move_insn (validize_mem (stack_parm),
5215 validize_mem (entry_parm));
5216 conversion_insns = get_insns ();
5220 emit_move_insn (validize_mem (stack_parm),
5221 validize_mem (entry_parm));
5224 SET_DECL_RTL (parm, stack_parm);
5228 if (SPLIT_COMPLEX_ARGS && fnargs != orig_fnargs)
5230 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
5232 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE)
5237 gen_rtx_CONCAT (DECL_MODE (parm),
5239 DECL_RTL (TREE_CHAIN (fnargs))));
5240 tmp = gen_rtx_CONCAT (DECL_MODE (parm),
5241 DECL_INCOMING_RTL (fnargs),
5242 DECL_INCOMING_RTL (TREE_CHAIN (fnargs)));
5243 set_decl_incoming_rtl (parm, tmp);
5244 fnargs = TREE_CHAIN (fnargs);
5248 SET_DECL_RTL (parm, DECL_RTL (fnargs));
5249 set_decl_incoming_rtl (parm, DECL_INCOMING_RTL (fnargs));
5251 fnargs = TREE_CHAIN (fnargs);
5255 /* Output all parameter conversion instructions (possibly including calls)
5256 now that all parameters have been copied out of hard registers. */
5257 emit_insn (conversion_insns);
5259 /* If we are receiving a struct value address as the first argument, set up
5260 the RTL for the function result. As this might require code to convert
5261 the transmitted address to Pmode, we do this here to ensure that possible
5262 preliminary conversions of the address have been emitted already. */
5263 if (function_result_decl)
5265 tree result = DECL_RESULT (fndecl);
5266 rtx addr = DECL_RTL (function_result_decl);
5269 addr = convert_memory_address (Pmode, addr);
5270 x = gen_rtx_MEM (DECL_MODE (result), addr);
5271 set_mem_attributes (x, result, 1);
5272 SET_DECL_RTL (result, x);
5275 last_parm_insn = get_last_insn ();
5277 current_function_args_size = stack_args_size.constant;
5279 /* Adjust function incoming argument size for alignment and
5282 #ifdef REG_PARM_STACK_SPACE
5283 #ifndef MAYBE_REG_PARM_STACK_SPACE
5284 current_function_args_size = MAX (current_function_args_size,
5285 REG_PARM_STACK_SPACE (fndecl));
5289 current_function_args_size
5290 = ((current_function_args_size + STACK_BYTES - 1)
5291 / STACK_BYTES) * STACK_BYTES;
5293 #ifdef ARGS_GROW_DOWNWARD
5294 current_function_arg_offset_rtx
5295 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5296 : expand_expr (size_diffop (stack_args_size.var,
5297 size_int (-stack_args_size.constant)),
5298 NULL_RTX, VOIDmode, 0));
5300 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5303 /* See how many bytes, if any, of its args a function should try to pop
5306 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5307 current_function_args_size);
5309 /* For stdarg.h function, save info about
5310 regs and stack space used by the named args. */
5312 current_function_args_info = args_so_far;
5314 /* Set the rtx used for the function return value. Put this in its
5315 own variable so any optimizers that need this information don't have
5316 to include tree.h. Do this here so it gets done when an inlined
5317 function gets output. */
5319 current_function_return_rtx
5320 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5321 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5323 /* If scalar return value was computed in a pseudo-reg, or was a named
5324 return value that got dumped to the stack, copy that to the hard
5326 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5328 tree decl_result = DECL_RESULT (fndecl);
5329 rtx decl_rtl = DECL_RTL (decl_result);
5331 if (REG_P (decl_rtl)
5332 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5333 : DECL_REGISTER (decl_result))
5337 #ifdef FUNCTION_OUTGOING_VALUE
5338 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5341 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5344 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5345 /* The delay slot scheduler assumes that current_function_return_rtx
5346 holds the hard register containing the return value, not a
5347 temporary pseudo. */
5348 current_function_return_rtx = real_decl_rtl;
5353 /* If ARGS contains entries with complex types, split the entry into two
5354 entries of the component type. Return a new list of substitutions are
5355 needed, else the old list. */
5358 split_complex_args (tree args)
5362 /* Before allocating memory, check for the common case of no complex. */
5363 for (p = args; p; p = TREE_CHAIN (p))
5364 if (TREE_CODE (TREE_TYPE (p)) == COMPLEX_TYPE)
5369 args = copy_list (args);
5371 for (p = args; p; p = TREE_CHAIN (p))
5373 tree type = TREE_TYPE (p);
5374 if (TREE_CODE (type) == COMPLEX_TYPE)
5377 tree subtype = TREE_TYPE (type);
5379 /* Rewrite the PARM_DECL's type with its component. */
5380 TREE_TYPE (p) = subtype;
5381 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
5382 DECL_MODE (p) = VOIDmode;
5383 DECL_SIZE (p) = NULL;
5384 DECL_SIZE_UNIT (p) = NULL;
5387 /* Build a second synthetic decl. */
5388 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
5389 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
5390 layout_decl (decl, 0);
5392 /* Splice it in; skip the new decl. */
5393 TREE_CHAIN (decl) = TREE_CHAIN (p);
5394 TREE_CHAIN (p) = decl;
5402 /* Indicate whether REGNO is an incoming argument to the current function
5403 that was promoted to a wider mode. If so, return the RTX for the
5404 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5405 that REGNO is promoted from and whether the promotion was signed or
5409 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
5413 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5414 arg = TREE_CHAIN (arg))
5415 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5416 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5417 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5419 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5420 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5422 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5423 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5424 && mode != DECL_MODE (arg))
5426 *pmode = DECL_MODE (arg);
5427 *punsignedp = unsignedp;
5428 return DECL_INCOMING_RTL (arg);
5436 /* Compute the size and offset from the start of the stacked arguments for a
5437 parm passed in mode PASSED_MODE and with type TYPE.
5439 INITIAL_OFFSET_PTR points to the current offset into the stacked
5442 The starting offset and size for this parm are returned in
5443 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5444 nonzero, the offset is that of stack slot, which is returned in
5445 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5446 padding required from the initial offset ptr to the stack slot.
5448 IN_REGS is nonzero if the argument will be passed in registers. It will
5449 never be set if REG_PARM_STACK_SPACE is not defined.
5451 FNDECL is the function in which the argument was defined.
5453 There are two types of rounding that are done. The first, controlled by
5454 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5455 list to be aligned to the specific boundary (in bits). This rounding
5456 affects the initial and starting offsets, but not the argument size.
5458 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5459 optionally rounds the size of the parm to PARM_BOUNDARY. The
5460 initial offset is not affected by this rounding, while the size always
5461 is and the starting offset may be. */
5463 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5464 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5465 callers pass in the total size of args so far as
5466 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5469 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
5470 int partial, tree fndecl ATTRIBUTE_UNUSED,
5471 struct args_size *initial_offset_ptr,
5472 struct locate_and_pad_arg_data *locate)
5475 enum direction where_pad;
5477 int reg_parm_stack_space = 0;
5478 int part_size_in_regs;
5480 #ifdef REG_PARM_STACK_SPACE
5481 #ifdef MAYBE_REG_PARM_STACK_SPACE
5482 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5484 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5487 /* If we have found a stack parm before we reach the end of the
5488 area reserved for registers, skip that area. */
5491 if (reg_parm_stack_space > 0)
5493 if (initial_offset_ptr->var)
5495 initial_offset_ptr->var
5496 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5497 ssize_int (reg_parm_stack_space));
5498 initial_offset_ptr->constant = 0;
5500 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5501 initial_offset_ptr->constant = reg_parm_stack_space;
5504 #endif /* REG_PARM_STACK_SPACE */
5506 part_size_in_regs = 0;
5507 if (reg_parm_stack_space == 0)
5508 part_size_in_regs = ((partial * UNITS_PER_WORD)
5509 / (PARM_BOUNDARY / BITS_PER_UNIT)
5510 * (PARM_BOUNDARY / BITS_PER_UNIT));
5513 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5514 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5515 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5516 locate->where_pad = where_pad;
5518 #ifdef ARGS_GROW_DOWNWARD
5519 locate->slot_offset.constant = -initial_offset_ptr->constant;
5520 if (initial_offset_ptr->var)
5521 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
5522 initial_offset_ptr->var);
5526 if (where_pad != none
5527 && (!host_integerp (sizetree, 1)
5528 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5529 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5530 SUB_PARM_SIZE (locate->slot_offset, s2);
5533 locate->slot_offset.constant += part_size_in_regs;
5536 #ifdef REG_PARM_STACK_SPACE
5537 || REG_PARM_STACK_SPACE (fndecl) > 0
5540 pad_to_arg_alignment (&locate->slot_offset, boundary,
5541 &locate->alignment_pad);
5543 locate->size.constant = (-initial_offset_ptr->constant
5544 - locate->slot_offset.constant);
5545 if (initial_offset_ptr->var)
5546 locate->size.var = size_binop (MINUS_EXPR,
5547 size_binop (MINUS_EXPR,
5549 initial_offset_ptr->var),
5550 locate->slot_offset.var);
5552 /* Pad_below needs the pre-rounded size to know how much to pad
5554 locate->offset = locate->slot_offset;
5555 if (where_pad == downward)
5556 pad_below (&locate->offset, passed_mode, sizetree);
5558 #else /* !ARGS_GROW_DOWNWARD */
5560 #ifdef REG_PARM_STACK_SPACE
5561 || REG_PARM_STACK_SPACE (fndecl) > 0
5564 pad_to_arg_alignment (initial_offset_ptr, boundary,
5565 &locate->alignment_pad);
5566 locate->slot_offset = *initial_offset_ptr;
5568 #ifdef PUSH_ROUNDING
5569 if (passed_mode != BLKmode)
5570 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5573 /* Pad_below needs the pre-rounded size to know how much to pad below
5574 so this must be done before rounding up. */
5575 locate->offset = locate->slot_offset;
5576 if (where_pad == downward)
5577 pad_below (&locate->offset, passed_mode, sizetree);
5579 if (where_pad != none
5580 && (!host_integerp (sizetree, 1)
5581 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5582 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5584 ADD_PARM_SIZE (locate->size, sizetree);
5586 locate->size.constant -= part_size_in_regs;
5587 #endif /* ARGS_GROW_DOWNWARD */
5590 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5591 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5594 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
5595 struct args_size *alignment_pad)
5597 tree save_var = NULL_TREE;
5598 HOST_WIDE_INT save_constant = 0;
5599 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5600 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
5602 #ifdef SPARC_STACK_BOUNDARY_HACK
5603 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
5604 higher than the real alignment of %sp. However, when it does this,
5605 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
5606 This is a temporary hack while the sparc port is fixed. */
5607 if (SPARC_STACK_BOUNDARY_HACK)
5611 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5613 save_var = offset_ptr->var;
5614 save_constant = offset_ptr->constant;
5617 alignment_pad->var = NULL_TREE;
5618 alignment_pad->constant = 0;
5620 if (boundary > BITS_PER_UNIT)
5622 if (offset_ptr->var)
5624 tree sp_offset_tree = ssize_int (sp_offset);
5625 tree offset = size_binop (PLUS_EXPR,
5626 ARGS_SIZE_TREE (*offset_ptr),
5628 #ifdef ARGS_GROW_DOWNWARD
5629 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
5631 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
5634 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
5635 /* ARGS_SIZE_TREE includes constant term. */
5636 offset_ptr->constant = 0;
5637 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5638 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5643 offset_ptr->constant = -sp_offset +
5644 #ifdef ARGS_GROW_DOWNWARD
5645 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5647 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5649 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5650 alignment_pad->constant = offset_ptr->constant - save_constant;
5656 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
5658 if (passed_mode != BLKmode)
5660 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5661 offset_ptr->constant
5662 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5663 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5664 - GET_MODE_SIZE (passed_mode));
5668 if (TREE_CODE (sizetree) != INTEGER_CST
5669 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5671 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5672 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5674 ADD_PARM_SIZE (*offset_ptr, s2);
5675 SUB_PARM_SIZE (*offset_ptr, sizetree);
5680 /* Walk the tree of blocks describing the binding levels within a function
5681 and warn about uninitialized variables.
5682 This is done after calling flow_analysis and before global_alloc
5683 clobbers the pseudo-regs to hard regs. */
5686 uninitialized_vars_warning (tree block)
5689 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5691 if (warn_uninitialized
5692 && TREE_CODE (decl) == VAR_DECL
5693 /* These warnings are unreliable for and aggregates
5694 because assigning the fields one by one can fail to convince
5695 flow.c that the entire aggregate was initialized.
5696 Unions are troublesome because members may be shorter. */
5697 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5698 && DECL_RTL (decl) != 0
5699 && GET_CODE (DECL_RTL (decl)) == REG
5700 /* Global optimizations can make it difficult to determine if a
5701 particular variable has been initialized. However, a VAR_DECL
5702 with a nonzero DECL_INITIAL had an initializer, so do not
5703 claim it is potentially uninitialized.
5705 When the DECL_INITIAL is NULL call the language hook to tell us
5706 if we want to warn. */
5707 && (DECL_INITIAL (decl) == NULL_TREE || lang_hooks.decl_uninit (decl))
5708 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5709 warning ("%J'%D' might be used uninitialized in this function",
5712 && TREE_CODE (decl) == VAR_DECL
5713 && DECL_RTL (decl) != 0
5714 && GET_CODE (DECL_RTL (decl)) == REG
5715 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5716 warning ("%Jvariable '%D' might be clobbered by `longjmp' or `vfork'",
5719 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5720 uninitialized_vars_warning (sub);
5723 /* Do the appropriate part of uninitialized_vars_warning
5724 but for arguments instead of local variables. */
5727 setjmp_args_warning (void)
5730 for (decl = DECL_ARGUMENTS (current_function_decl);
5731 decl; decl = TREE_CHAIN (decl))
5732 if (DECL_RTL (decl) != 0
5733 && GET_CODE (DECL_RTL (decl)) == REG
5734 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5735 warning ("%Jargument '%D' might be clobbered by `longjmp' or `vfork'",
5739 /* If this function call setjmp, put all vars into the stack
5740 unless they were declared `register'. */
5743 setjmp_protect (tree block)
5746 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5747 if ((TREE_CODE (decl) == VAR_DECL
5748 || TREE_CODE (decl) == PARM_DECL)
5749 && DECL_RTL (decl) != 0
5750 && (GET_CODE (DECL_RTL (decl)) == REG
5751 || (GET_CODE (DECL_RTL (decl)) == MEM
5752 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5753 /* If this variable came from an inline function, it must be
5754 that its life doesn't overlap the setjmp. If there was a
5755 setjmp in the function, it would already be in memory. We
5756 must exclude such variable because their DECL_RTL might be
5757 set to strange things such as virtual_stack_vars_rtx. */
5758 && ! DECL_FROM_INLINE (decl)
5760 #ifdef NON_SAVING_SETJMP
5761 /* If longjmp doesn't restore the registers,
5762 don't put anything in them. */
5766 ! DECL_REGISTER (decl)))
5767 put_var_into_stack (decl, /*rescan=*/true);
5768 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5769 setjmp_protect (sub);
5772 /* Like the previous function, but for args instead of local variables. */
5775 setjmp_protect_args (void)
5778 for (decl = DECL_ARGUMENTS (current_function_decl);
5779 decl; decl = TREE_CHAIN (decl))
5780 if ((TREE_CODE (decl) == VAR_DECL
5781 || TREE_CODE (decl) == PARM_DECL)
5782 && DECL_RTL (decl) != 0
5783 && (GET_CODE (DECL_RTL (decl)) == REG
5784 || (GET_CODE (DECL_RTL (decl)) == MEM
5785 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5787 /* If longjmp doesn't restore the registers,
5788 don't put anything in them. */
5789 #ifdef NON_SAVING_SETJMP
5793 ! DECL_REGISTER (decl)))
5794 put_var_into_stack (decl, /*rescan=*/true);
5797 /* Return the context-pointer register corresponding to DECL,
5798 or 0 if it does not need one. */
5801 lookup_static_chain (tree decl)
5803 tree context = decl_function_context (decl);
5807 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5810 /* We treat inline_function_decl as an alias for the current function
5811 because that is the inline function whose vars, types, etc.
5812 are being merged into the current function.
5813 See expand_inline_function. */
5814 if (context == current_function_decl || context == inline_function_decl)
5815 return virtual_stack_vars_rtx;
5817 for (link = context_display; link; link = TREE_CHAIN (link))
5818 if (TREE_PURPOSE (link) == context)
5819 return RTL_EXPR_RTL (TREE_VALUE (link));
5824 /* Convert a stack slot address ADDR for variable VAR
5825 (from a containing function)
5826 into an address valid in this function (using a static chain). */
5829 fix_lexical_addr (rtx addr, tree var)
5832 HOST_WIDE_INT displacement;
5833 tree context = decl_function_context (var);
5834 struct function *fp;
5837 /* If this is the present function, we need not do anything. */
5838 if (context == current_function_decl || context == inline_function_decl)
5841 fp = find_function_data (context);
5843 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5844 addr = XEXP (XEXP (addr, 0), 0);
5846 /* Decode given address as base reg plus displacement. */
5847 if (GET_CODE (addr) == REG)
5848 basereg = addr, displacement = 0;
5849 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5850 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5854 /* We accept vars reached via the containing function's
5855 incoming arg pointer and via its stack variables pointer. */
5856 if (basereg == fp->internal_arg_pointer)
5858 /* If reached via arg pointer, get the arg pointer value
5859 out of that function's stack frame.
5861 There are two cases: If a separate ap is needed, allocate a
5862 slot in the outer function for it and dereference it that way.
5863 This is correct even if the real ap is actually a pseudo.
5864 Otherwise, just adjust the offset from the frame pointer to
5867 #ifdef NEED_SEPARATE_AP
5870 addr = get_arg_pointer_save_area (fp);
5871 addr = fix_lexical_addr (XEXP (addr, 0), var);
5872 addr = memory_address (Pmode, addr);
5874 base = gen_rtx_MEM (Pmode, addr);
5875 set_mem_alias_set (base, get_frame_alias_set ());
5876 base = copy_to_reg (base);
5878 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5879 base = lookup_static_chain (var);
5883 else if (basereg == virtual_stack_vars_rtx)
5885 /* This is the same code as lookup_static_chain, duplicated here to
5886 avoid an extra call to decl_function_context. */
5889 for (link = context_display; link; link = TREE_CHAIN (link))
5890 if (TREE_PURPOSE (link) == context)
5892 base = RTL_EXPR_RTL (TREE_VALUE (link));
5900 /* Use same offset, relative to appropriate static chain or argument
5902 return plus_constant (base, displacement);
5905 /* Return the address of the trampoline for entering nested fn FUNCTION.
5906 If necessary, allocate a trampoline (in the stack frame)
5907 and emit rtl to initialize its contents (at entry to this function). */
5910 trampoline_address (tree function)
5915 struct function *fp;
5918 /* Find an existing trampoline and return it. */
5919 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5920 if (TREE_PURPOSE (link) == function)
5922 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5924 for (fp = outer_function_chain; fp; fp = fp->outer)
5925 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5926 if (TREE_PURPOSE (link) == function)
5928 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5930 return adjust_trampoline_addr (tramp);
5933 /* None exists; we must make one. */
5935 /* Find the `struct function' for the function containing FUNCTION. */
5937 fn_context = decl_function_context (function);
5938 if (fn_context != current_function_decl
5939 && fn_context != inline_function_decl)
5940 fp = find_function_data (fn_context);
5942 /* Allocate run-time space for this trampoline. */
5943 /* If rounding needed, allocate extra space
5944 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5945 #define TRAMPOLINE_REAL_SIZE \
5946 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5947 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5949 /* Record the trampoline for reuse and note it for later initialization
5950 by expand_function_end. */
5953 rtlexp = make_node (RTL_EXPR);
5954 RTL_EXPR_RTL (rtlexp) = tramp;
5955 fp->x_trampoline_list = tree_cons (function, rtlexp,
5956 fp->x_trampoline_list);
5960 /* Make the RTL_EXPR node temporary, not momentary, so that the
5961 trampoline_list doesn't become garbage. */
5962 rtlexp = make_node (RTL_EXPR);
5964 RTL_EXPR_RTL (rtlexp) = tramp;
5965 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5968 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5969 return adjust_trampoline_addr (tramp);
5972 /* Given a trampoline address,
5973 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5976 round_trampoline_addr (rtx tramp)
5978 /* Round address up to desired boundary. */
5979 rtx temp = gen_reg_rtx (Pmode);
5980 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5981 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5983 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5984 temp, 0, OPTAB_LIB_WIDEN);
5985 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5986 temp, 0, OPTAB_LIB_WIDEN);
5991 /* Given a trampoline address, round it then apply any
5992 platform-specific adjustments so that the result can be used for a
5996 adjust_trampoline_addr (rtx tramp)
5998 tramp = round_trampoline_addr (tramp);
5999 #ifdef TRAMPOLINE_ADJUST_ADDRESS
6000 TRAMPOLINE_ADJUST_ADDRESS (tramp);
6005 /* Put all this function's BLOCK nodes including those that are chained
6006 onto the first block into a vector, and return it.
6007 Also store in each NOTE for the beginning or end of a block
6008 the index of that block in the vector.
6009 The arguments are BLOCK, the chain of top-level blocks of the function,
6010 and INSNS, the insn chain of the function. */
6013 identify_blocks (void)
6016 tree *block_vector, *last_block_vector;
6018 tree block = DECL_INITIAL (current_function_decl);
6023 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
6024 depth-first order. */
6025 block_vector = get_block_vector (block, &n_blocks);
6026 block_stack = xmalloc (n_blocks * sizeof (tree));
6028 last_block_vector = identify_blocks_1 (get_insns (),
6030 block_vector + n_blocks,
6033 /* If we didn't use all of the subblocks, we've misplaced block notes. */
6034 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
6035 if (0 && last_block_vector != block_vector + n_blocks)
6038 free (block_vector);
6042 /* Subroutine of identify_blocks. Do the block substitution on the
6043 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
6045 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
6046 BLOCK_VECTOR is incremented for each block seen. */
6049 identify_blocks_1 (rtx insns, tree *block_vector, tree *end_block_vector,
6050 tree *orig_block_stack)
6053 tree *block_stack = orig_block_stack;
6055 for (insn = insns; insn; insn = NEXT_INSN (insn))
6057 if (GET_CODE (insn) == NOTE)
6059 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6063 /* If there are more block notes than BLOCKs, something
6065 if (block_vector == end_block_vector)
6068 b = *block_vector++;
6069 NOTE_BLOCK (insn) = b;
6072 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6074 /* If there are more NOTE_INSN_BLOCK_ENDs than
6075 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
6076 if (block_stack == orig_block_stack)
6079 NOTE_BLOCK (insn) = *--block_stack;
6082 else if (GET_CODE (insn) == CALL_INSN
6083 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6085 rtx cp = PATTERN (insn);
6087 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
6088 end_block_vector, block_stack);
6090 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
6091 end_block_vector, block_stack);
6093 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
6094 end_block_vector, block_stack);
6098 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
6099 something is badly wrong. */
6100 if (block_stack != orig_block_stack)
6103 return block_vector;
6106 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
6107 and create duplicate blocks. */
6108 /* ??? Need an option to either create block fragments or to create
6109 abstract origin duplicates of a source block. It really depends
6110 on what optimization has been performed. */
6113 reorder_blocks (void)
6115 tree block = DECL_INITIAL (current_function_decl);
6116 varray_type block_stack;
6118 if (block == NULL_TREE)
6121 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
6123 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
6124 reorder_blocks_0 (block);
6126 /* Prune the old trees away, so that they don't get in the way. */
6127 BLOCK_SUBBLOCKS (block) = NULL_TREE;
6128 BLOCK_CHAIN (block) = NULL_TREE;
6130 /* Recreate the block tree from the note nesting. */
6131 reorder_blocks_1 (get_insns (), block, &block_stack);
6132 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
6134 /* Remove deleted blocks from the block fragment chains. */
6135 reorder_fix_fragments (block);
6138 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
6141 reorder_blocks_0 (tree block)
6145 TREE_ASM_WRITTEN (block) = 0;
6146 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
6147 block = BLOCK_CHAIN (block);
6152 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack)
6156 for (insn = insns; insn; insn = NEXT_INSN (insn))
6158 if (GET_CODE (insn) == NOTE)
6160 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6162 tree block = NOTE_BLOCK (insn);
6164 /* If we have seen this block before, that means it now
6165 spans multiple address regions. Create a new fragment. */
6166 if (TREE_ASM_WRITTEN (block))
6168 tree new_block = copy_node (block);
6171 origin = (BLOCK_FRAGMENT_ORIGIN (block)
6172 ? BLOCK_FRAGMENT_ORIGIN (block)
6174 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
6175 BLOCK_FRAGMENT_CHAIN (new_block)
6176 = BLOCK_FRAGMENT_CHAIN (origin);
6177 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
6179 NOTE_BLOCK (insn) = new_block;
6183 BLOCK_SUBBLOCKS (block) = 0;
6184 TREE_ASM_WRITTEN (block) = 1;
6185 /* When there's only one block for the entire function,
6186 current_block == block and we mustn't do this, it
6187 will cause infinite recursion. */
6188 if (block != current_block)
6190 BLOCK_SUPERCONTEXT (block) = current_block;
6191 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6192 BLOCK_SUBBLOCKS (current_block) = block;
6193 current_block = block;
6195 VARRAY_PUSH_TREE (*p_block_stack, block);
6197 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6199 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6200 VARRAY_POP (*p_block_stack);
6201 BLOCK_SUBBLOCKS (current_block)
6202 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6203 current_block = BLOCK_SUPERCONTEXT (current_block);
6206 else if (GET_CODE (insn) == CALL_INSN
6207 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6209 rtx cp = PATTERN (insn);
6210 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
6212 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6214 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6219 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6220 appears in the block tree, select one of the fragments to become
6221 the new origin block. */
6224 reorder_fix_fragments (tree block)
6228 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6229 tree new_origin = NULL_TREE;
6233 if (! TREE_ASM_WRITTEN (dup_origin))
6235 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6237 /* Find the first of the remaining fragments. There must
6238 be at least one -- the current block. */
6239 while (! TREE_ASM_WRITTEN (new_origin))
6240 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6241 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6244 else if (! dup_origin)
6247 /* Re-root the rest of the fragments to the new origin. In the
6248 case that DUP_ORIGIN was null, that means BLOCK was the origin
6249 of a chain of fragments and we want to remove those fragments
6250 that didn't make it to the output. */
6253 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6258 if (TREE_ASM_WRITTEN (chain))
6260 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6262 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6264 chain = BLOCK_FRAGMENT_CHAIN (chain);
6269 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6270 block = BLOCK_CHAIN (block);
6274 /* Reverse the order of elements in the chain T of blocks,
6275 and return the new head of the chain (old last element). */
6278 blocks_nreverse (tree t)
6280 tree prev = 0, decl, next;
6281 for (decl = t; decl; decl = next)
6283 next = BLOCK_CHAIN (decl);
6284 BLOCK_CHAIN (decl) = prev;
6290 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6291 non-NULL, list them all into VECTOR, in a depth-first preorder
6292 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6296 all_blocks (tree block, tree *vector)
6302 TREE_ASM_WRITTEN (block) = 0;
6304 /* Record this block. */
6306 vector[n_blocks] = block;
6310 /* Record the subblocks, and their subblocks... */
6311 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6312 vector ? vector + n_blocks : 0);
6313 block = BLOCK_CHAIN (block);
6319 /* Return a vector containing all the blocks rooted at BLOCK. The
6320 number of elements in the vector is stored in N_BLOCKS_P. The
6321 vector is dynamically allocated; it is the caller's responsibility
6322 to call `free' on the pointer returned. */
6325 get_block_vector (tree block, int *n_blocks_p)
6329 *n_blocks_p = all_blocks (block, NULL);
6330 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
6331 all_blocks (block, block_vector);
6333 return block_vector;
6336 static GTY(()) int next_block_index = 2;
6338 /* Set BLOCK_NUMBER for all the blocks in FN. */
6341 number_blocks (tree fn)
6347 /* For SDB and XCOFF debugging output, we start numbering the blocks
6348 from 1 within each function, rather than keeping a running
6350 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6351 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6352 next_block_index = 1;
6355 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6357 /* The top-level BLOCK isn't numbered at all. */
6358 for (i = 1; i < n_blocks; ++i)
6359 /* We number the blocks from two. */
6360 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6362 free (block_vector);
6367 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6370 debug_find_var_in_block_tree (tree var, tree block)
6374 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6378 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6380 tree ret = debug_find_var_in_block_tree (var, t);
6388 /* Allocate a function structure for FNDECL and set its contents
6392 allocate_struct_function (tree fndecl)
6396 cfun = ggc_alloc_cleared (sizeof (struct function));
6398 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6400 cfun->stack_alignment_needed = STACK_BOUNDARY;
6401 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6403 current_function_funcdef_no = funcdef_no++;
6405 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6407 init_stmt_for_function ();
6408 init_eh_for_function ();
6410 (*lang_hooks.function.init) (cfun);
6411 if (init_machine_status)
6412 cfun->machine = (*init_machine_status) ();
6417 DECL_SAVED_INSNS (fndecl) = cfun;
6418 cfun->decl = fndecl;
6420 result = DECL_RESULT (fndecl);
6421 if (aggregate_value_p (result, fndecl))
6423 #ifdef PCC_STATIC_STRUCT_RETURN
6424 current_function_returns_pcc_struct = 1;
6426 current_function_returns_struct = 1;
6429 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
6431 current_function_needs_context
6432 = (decl_function_context (current_function_decl) != 0
6433 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6436 /* Reset cfun, and other non-struct-function variables to defaults as
6437 appropriate for emitting rtl at the start of a function. */
6440 prepare_function_start (tree fndecl)
6442 if (fndecl && DECL_SAVED_INSNS (fndecl))
6443 cfun = DECL_SAVED_INSNS (fndecl);
6445 allocate_struct_function (fndecl);
6447 init_varasm_status (cfun);
6450 cse_not_expected = ! optimize;
6452 /* Caller save not needed yet. */
6453 caller_save_needed = 0;
6455 /* We haven't done register allocation yet. */
6458 /* Indicate that we need to distinguish between the return value of the
6459 present function and the return value of a function being called. */
6460 rtx_equal_function_value_matters = 1;
6462 /* Indicate that we have not instantiated virtual registers yet. */
6463 virtuals_instantiated = 0;
6465 /* Indicate that we want CONCATs now. */
6466 generating_concat_p = 1;
6468 /* Indicate we have no need of a frame pointer yet. */
6469 frame_pointer_needed = 0;
6472 /* Initialize the rtl expansion mechanism so that we can do simple things
6473 like generate sequences. This is used to provide a context during global
6474 initialization of some passes. */
6476 init_dummy_function_start (void)
6478 prepare_function_start (NULL);
6481 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6482 and initialize static variables for generating RTL for the statements
6486 init_function_start (tree subr)
6488 prepare_function_start (subr);
6490 /* Within function body, compute a type's size as soon it is laid out. */
6491 immediate_size_expand++;
6493 /* Prevent ever trying to delete the first instruction of a
6494 function. Also tell final how to output a linenum before the
6495 function prologue. Note linenums could be missing, e.g. when
6496 compiling a Java .class file. */
6497 if (DECL_SOURCE_LINE (subr))
6498 emit_line_note (DECL_SOURCE_LOCATION (subr));
6500 /* Make sure first insn is a note even if we don't want linenums.
6501 This makes sure the first insn will never be deleted.
6502 Also, final expects a note to appear there. */
6503 emit_note (NOTE_INSN_DELETED);
6505 /* Warn if this value is an aggregate type,
6506 regardless of which calling convention we are using for it. */
6507 if (warn_aggregate_return
6508 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6509 warning ("function returns an aggregate");
6512 /* Make sure all values used by the optimization passes have sane
6515 init_function_for_compilation (void)
6519 /* No prologue/epilogue insns yet. */
6520 VARRAY_GROW (prologue, 0);
6521 VARRAY_GROW (epilogue, 0);
6522 VARRAY_GROW (sibcall_epilogue, 0);
6525 /* Expand a call to __main at the beginning of a possible main function. */
6527 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6528 #undef HAS_INIT_SECTION
6529 #define HAS_INIT_SECTION
6533 expand_main_function (void)
6535 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6536 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6538 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6542 /* Forcibly align the stack. */
6543 #ifdef STACK_GROWS_DOWNWARD
6544 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6545 stack_pointer_rtx, 1, OPTAB_WIDEN);
6547 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6548 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6549 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6550 stack_pointer_rtx, 1, OPTAB_WIDEN);
6552 if (tmp != stack_pointer_rtx)
6553 emit_move_insn (stack_pointer_rtx, tmp);
6555 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6556 tmp = force_reg (Pmode, const0_rtx);
6557 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6561 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6562 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6565 emit_insn_before (seq, tmp);
6571 #ifndef HAS_INIT_SECTION
6572 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6576 /* The PENDING_SIZES represent the sizes of variable-sized types.
6577 Create RTL for the various sizes now (using temporary variables),
6578 so that we can refer to the sizes from the RTL we are generating
6579 for the current function. The PENDING_SIZES are a TREE_LIST. The
6580 TREE_VALUE of each node is a SAVE_EXPR. */
6583 expand_pending_sizes (tree pending_sizes)
6587 /* Evaluate now the sizes of any types declared among the arguments. */
6588 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6590 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6591 /* Flush the queue in case this parameter declaration has
6597 /* Start the RTL for a new function, and set variables used for
6599 SUBR is the FUNCTION_DECL node.
6600 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6601 the function's parameters, which must be run at any return statement. */
6604 expand_function_start (tree subr, int parms_have_cleanups)
6607 rtx last_ptr = NULL_RTX;
6609 /* Make sure volatile mem refs aren't considered
6610 valid operands of arithmetic insns. */
6611 init_recog_no_volatile ();
6613 current_function_instrument_entry_exit
6614 = (flag_instrument_function_entry_exit
6615 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6617 current_function_profile
6619 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6621 current_function_limit_stack
6622 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6624 /* If function gets a static chain arg, store it in the stack frame.
6625 Do this first, so it gets the first stack slot offset. */
6626 if (current_function_needs_context)
6628 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6630 /* Delay copying static chain if it is not a register to avoid
6631 conflicts with regs used for parameters. */
6632 if (! SMALL_REGISTER_CLASSES
6633 || GET_CODE (static_chain_incoming_rtx) == REG)
6634 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6637 /* If the parameters of this function need cleaning up, get a label
6638 for the beginning of the code which executes those cleanups. This must
6639 be done before doing anything with return_label. */
6640 if (parms_have_cleanups)
6641 cleanup_label = gen_label_rtx ();
6645 /* Make the label for return statements to jump to. Do not special
6646 case machines with special return instructions -- they will be
6647 handled later during jump, ifcvt, or epilogue creation. */
6648 return_label = gen_label_rtx ();
6650 /* Initialize rtx used to return the value. */
6651 /* Do this before assign_parms so that we copy the struct value address
6652 before any library calls that assign parms might generate. */
6654 /* Decide whether to return the value in memory or in a register. */
6655 if (aggregate_value_p (DECL_RESULT (subr), subr))
6657 /* Returning something that won't go in a register. */
6658 rtx value_address = 0;
6660 #ifdef PCC_STATIC_STRUCT_RETURN
6661 if (current_function_returns_pcc_struct)
6663 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6664 value_address = assemble_static_space (size);
6669 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
6670 /* Expect to be passed the address of a place to store the value.
6671 If it is passed as an argument, assign_parms will take care of
6675 value_address = gen_reg_rtx (Pmode);
6676 emit_move_insn (value_address, sv);
6681 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6682 set_mem_attributes (x, DECL_RESULT (subr), 1);
6683 SET_DECL_RTL (DECL_RESULT (subr), x);
6686 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6687 /* If return mode is void, this decl rtl should not be used. */
6688 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6691 /* Compute the return values into a pseudo reg, which we will copy
6692 into the true return register after the cleanups are done. */
6694 /* In order to figure out what mode to use for the pseudo, we
6695 figure out what the mode of the eventual return register will
6696 actually be, and use that. */
6698 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6701 /* Structures that are returned in registers are not aggregate_value_p,
6702 so we may see a PARALLEL or a REG. */
6703 if (REG_P (hard_reg))
6704 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6705 else if (GET_CODE (hard_reg) == PARALLEL)
6706 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6710 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6711 result to the real return register(s). */
6712 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6715 /* Initialize rtx for parameters and local variables.
6716 In some cases this requires emitting insns. */
6718 assign_parms (subr);
6720 /* Copy the static chain now if it wasn't a register. The delay is to
6721 avoid conflicts with the parameter passing registers. */
6723 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6724 if (GET_CODE (static_chain_incoming_rtx) != REG)
6725 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6727 /* The following was moved from init_function_start.
6728 The move is supposed to make sdb output more accurate. */
6729 /* Indicate the beginning of the function body,
6730 as opposed to parm setup. */
6731 emit_note (NOTE_INSN_FUNCTION_BEG);
6733 if (GET_CODE (get_last_insn ()) != NOTE)
6734 emit_note (NOTE_INSN_DELETED);
6735 parm_birth_insn = get_last_insn ();
6737 context_display = 0;
6738 if (current_function_needs_context)
6740 /* Fetch static chain values for containing functions. */
6741 tem = decl_function_context (current_function_decl);
6742 /* Copy the static chain pointer into a pseudo. If we have
6743 small register classes, copy the value from memory if
6744 static_chain_incoming_rtx is a REG. */
6747 /* If the static chain originally came in a register, put it back
6748 there, then move it out in the next insn. The reason for
6749 this peculiar code is to satisfy function integration. */
6750 if (SMALL_REGISTER_CLASSES
6751 && GET_CODE (static_chain_incoming_rtx) == REG)
6752 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6753 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6758 tree rtlexp = make_node (RTL_EXPR);
6760 RTL_EXPR_RTL (rtlexp) = last_ptr;
6761 context_display = tree_cons (tem, rtlexp, context_display);
6762 tem = decl_function_context (tem);
6765 /* Chain through stack frames, assuming pointer to next lexical frame
6766 is found at the place we always store it. */
6767 #ifdef FRAME_GROWS_DOWNWARD
6768 last_ptr = plus_constant (last_ptr,
6769 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6771 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6772 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6773 last_ptr = copy_to_reg (last_ptr);
6775 /* If we are not optimizing, ensure that we know that this
6776 piece of context is live over the entire function. */
6778 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6783 if (current_function_instrument_entry_exit)
6785 rtx fun = DECL_RTL (current_function_decl);
6786 if (GET_CODE (fun) == MEM)
6787 fun = XEXP (fun, 0);
6790 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6792 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6794 hard_frame_pointer_rtx),
6798 if (current_function_profile)
6801 PROFILE_HOOK (current_function_funcdef_no);
6805 /* After the display initializations is where the tail-recursion label
6806 should go, if we end up needing one. Ensure we have a NOTE here
6807 since some things (like trampolines) get placed before this. */
6808 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
6810 /* Evaluate now the sizes of any types declared among the arguments. */
6811 expand_pending_sizes (nreverse (get_pending_sizes ()));
6813 /* Make sure there is a line number after the function entry setup code. */
6814 force_next_line_note ();
6817 /* Undo the effects of init_dummy_function_start. */
6819 expand_dummy_function_end (void)
6821 /* End any sequences that failed to be closed due to syntax errors. */
6822 while (in_sequence_p ())
6825 /* Outside function body, can't compute type's actual size
6826 until next function's body starts. */
6828 free_after_parsing (cfun);
6829 free_after_compilation (cfun);
6833 /* Call DOIT for each hard register used as a return value from
6834 the current function. */
6837 diddle_return_value (void (*doit) (rtx, void *), void *arg)
6839 rtx outgoing = current_function_return_rtx;
6844 if (GET_CODE (outgoing) == REG)
6845 (*doit) (outgoing, arg);
6846 else if (GET_CODE (outgoing) == PARALLEL)
6850 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6852 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6854 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6861 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6863 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6867 clobber_return_register (void)
6869 diddle_return_value (do_clobber_return_reg, NULL);
6871 /* In case we do use pseudo to return value, clobber it too. */
6872 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6874 tree decl_result = DECL_RESULT (current_function_decl);
6875 rtx decl_rtl = DECL_RTL (decl_result);
6876 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6878 do_clobber_return_reg (decl_rtl, NULL);
6884 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6886 emit_insn (gen_rtx_USE (VOIDmode, reg));
6890 use_return_register (void)
6892 diddle_return_value (do_use_return_reg, NULL);
6895 static GTY(()) rtx initial_trampoline;
6897 /* Generate RTL for the end of the current function. */
6900 expand_function_end (void)
6905 finish_expr_for_function ();
6907 /* If arg_pointer_save_area was referenced only from a nested
6908 function, we will not have initialized it yet. Do that now. */
6909 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6910 get_arg_pointer_save_area (cfun);
6912 #ifdef NON_SAVING_SETJMP
6913 /* Don't put any variables in registers if we call setjmp
6914 on a machine that fails to restore the registers. */
6915 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6917 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6918 setjmp_protect (DECL_INITIAL (current_function_decl));
6920 setjmp_protect_args ();
6924 /* Initialize any trampolines required by this function. */
6925 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6927 tree function = TREE_PURPOSE (link);
6928 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6929 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6930 #ifdef TRAMPOLINE_TEMPLATE
6935 #ifdef TRAMPOLINE_TEMPLATE
6936 /* First make sure this compilation has a template for
6937 initializing trampolines. */
6938 if (initial_trampoline == 0)
6941 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6942 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6946 /* Generate insns to initialize the trampoline. */
6948 tramp = round_trampoline_addr (XEXP (tramp, 0));
6949 #ifdef TRAMPOLINE_TEMPLATE
6950 blktramp = replace_equiv_address (initial_trampoline, tramp);
6951 emit_block_move (blktramp, initial_trampoline,
6952 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6954 trampolines_created = 1;
6955 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6959 /* Put those insns at entry to the containing function (this one). */
6960 emit_insn_before (seq, tail_recursion_reentry);
6963 /* If we are doing stack checking and this function makes calls,
6964 do a stack probe at the start of the function to ensure we have enough
6965 space for another stack frame. */
6966 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6970 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6971 if (GET_CODE (insn) == CALL_INSN)
6974 probe_stack_range (STACK_CHECK_PROTECT,
6975 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6978 emit_insn_before (seq, tail_recursion_reentry);
6983 /* Possibly warn about unused parameters. */
6984 if (warn_unused_parameter)
6988 for (decl = DECL_ARGUMENTS (current_function_decl);
6989 decl; decl = TREE_CHAIN (decl))
6990 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6991 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6992 warning ("%Junused parameter '%D'", decl, decl);
6995 /* Delete handlers for nonlocal gotos if nothing uses them. */
6996 if (nonlocal_goto_handler_slots != 0
6997 && ! current_function_has_nonlocal_label)
7000 /* End any sequences that failed to be closed due to syntax errors. */
7001 while (in_sequence_p ())
7004 /* Outside function body, can't compute type's actual size
7005 until next function's body starts. */
7006 immediate_size_expand--;
7008 clear_pending_stack_adjust ();
7009 do_pending_stack_adjust ();
7011 /* Mark the end of the function body.
7012 If control reaches this insn, the function can drop through
7013 without returning a value. */
7014 emit_note (NOTE_INSN_FUNCTION_END);
7016 /* Must mark the last line number note in the function, so that the test
7017 coverage code can avoid counting the last line twice. This just tells
7018 the code to ignore the immediately following line note, since there
7019 already exists a copy of this note somewhere above. This line number
7020 note is still needed for debugging though, so we can't delete it. */
7021 if (flag_test_coverage)
7022 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
7024 /* Output a linenumber for the end of the function.
7025 SDB depends on this. */
7026 force_next_line_note ();
7027 emit_line_note (input_location);
7029 /* Before the return label (if any), clobber the return
7030 registers so that they are not propagated live to the rest of
7031 the function. This can only happen with functions that drop
7032 through; if there had been a return statement, there would
7033 have either been a return rtx, or a jump to the return label.
7035 We delay actual code generation after the current_function_value_rtx
7037 clobber_after = get_last_insn ();
7039 /* Output the label for the actual return from the function,
7040 if one is expected. This happens either because a function epilogue
7041 is used instead of a return instruction, or because a return was done
7042 with a goto in order to run local cleanups, or because of pcc-style
7043 structure returning. */
7045 emit_label (return_label);
7047 if (current_function_instrument_entry_exit)
7049 rtx fun = DECL_RTL (current_function_decl);
7050 if (GET_CODE (fun) == MEM)
7051 fun = XEXP (fun, 0);
7054 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
7056 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
7058 hard_frame_pointer_rtx),
7062 /* Let except.c know where it should emit the call to unregister
7063 the function context for sjlj exceptions. */
7064 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
7065 sjlj_emit_function_exit_after (get_last_insn ());
7067 /* If we had calls to alloca, and this machine needs
7068 an accurate stack pointer to exit the function,
7069 insert some code to save and restore the stack pointer. */
7070 if (! EXIT_IGNORE_STACK
7071 && current_function_calls_alloca)
7075 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
7076 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
7079 /* If scalar return value was computed in a pseudo-reg, or was a named
7080 return value that got dumped to the stack, copy that to the hard
7082 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
7084 tree decl_result = DECL_RESULT (current_function_decl);
7085 rtx decl_rtl = DECL_RTL (decl_result);
7087 if (REG_P (decl_rtl)
7088 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
7089 : DECL_REGISTER (decl_result))
7091 rtx real_decl_rtl = current_function_return_rtx;
7093 /* This should be set in assign_parms. */
7094 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
7097 /* If this is a BLKmode structure being returned in registers,
7098 then use the mode computed in expand_return. Note that if
7099 decl_rtl is memory, then its mode may have been changed,
7100 but that current_function_return_rtx has not. */
7101 if (GET_MODE (real_decl_rtl) == BLKmode)
7102 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
7104 /* If a named return value dumped decl_return to memory, then
7105 we may need to re-do the PROMOTE_MODE signed/unsigned
7107 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
7109 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
7111 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
7112 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7115 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7117 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7119 /* If expand_function_start has created a PARALLEL for decl_rtl,
7120 move the result to the real return registers. Otherwise, do
7121 a group load from decl_rtl for a named return. */
7122 if (GET_CODE (decl_rtl) == PARALLEL)
7123 emit_group_move (real_decl_rtl, decl_rtl);
7125 emit_group_load (real_decl_rtl, decl_rtl,
7126 TREE_TYPE (decl_result),
7127 int_size_in_bytes (TREE_TYPE (decl_result)));
7130 emit_move_insn (real_decl_rtl, decl_rtl);
7134 /* If returning a structure, arrange to return the address of the value
7135 in a place where debuggers expect to find it.
7137 If returning a structure PCC style,
7138 the caller also depends on this value.
7139 And current_function_returns_pcc_struct is not necessarily set. */
7140 if (current_function_returns_struct
7141 || current_function_returns_pcc_struct)
7144 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7145 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7146 #ifdef FUNCTION_OUTGOING_VALUE
7148 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7149 current_function_decl);
7152 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7155 /* Mark this as a function return value so integrate will delete the
7156 assignment and USE below when inlining this function. */
7157 REG_FUNCTION_VALUE_P (outgoing) = 1;
7159 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7160 value_address = convert_memory_address (GET_MODE (outgoing),
7163 emit_move_insn (outgoing, value_address);
7165 /* Show return register used to hold result (in this case the address
7167 current_function_return_rtx = outgoing;
7170 /* If this is an implementation of throw, do what's necessary to
7171 communicate between __builtin_eh_return and the epilogue. */
7172 expand_eh_return ();
7174 /* Emit the actual code to clobber return register. */
7179 clobber_return_register ();
7183 after = emit_insn_after (seq, clobber_after);
7185 if (clobber_after != after)
7186 cfun->x_clobber_return_insn = after;
7189 /* Output the label for the naked return from the function, if one is
7190 expected. This is currently used only by __builtin_return. */
7191 if (naked_return_label)
7192 emit_label (naked_return_label);
7194 /* ??? This should no longer be necessary since stupid is no longer with
7195 us, but there are some parts of the compiler (eg reload_combine, and
7196 sh mach_dep_reorg) that still try and compute their own lifetime info
7197 instead of using the general framework. */
7198 use_return_register ();
7200 /* Fix up any gotos that jumped out to the outermost
7201 binding level of the function.
7202 Must follow emitting RETURN_LABEL. */
7204 /* If you have any cleanups to do at this point,
7205 and they need to create temporary variables,
7206 then you will lose. */
7207 expand_fixups (get_insns ());
7211 get_arg_pointer_save_area (struct function *f)
7213 rtx ret = f->x_arg_pointer_save_area;
7217 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7218 f->x_arg_pointer_save_area = ret;
7221 if (f == cfun && ! f->arg_pointer_save_area_init)
7225 /* Save the arg pointer at the beginning of the function. The
7226 generated stack slot may not be a valid memory address, so we
7227 have to check it and fix it if necessary. */
7229 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7233 push_topmost_sequence ();
7234 emit_insn_after (seq, get_insns ());
7235 pop_topmost_sequence ();
7241 /* Extend a vector that records the INSN_UIDs of INSNS
7242 (a list of one or more insns). */
7245 record_insns (rtx insns, varray_type *vecp)
7252 while (tmp != NULL_RTX)
7255 tmp = NEXT_INSN (tmp);
7258 i = VARRAY_SIZE (*vecp);
7259 VARRAY_GROW (*vecp, i + len);
7261 while (tmp != NULL_RTX)
7263 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7265 tmp = NEXT_INSN (tmp);
7269 /* Set the locator of the insn chain starting at INSN to LOC. */
7271 set_insn_locators (rtx insn, int loc)
7273 while (insn != NULL_RTX)
7276 INSN_LOCATOR (insn) = loc;
7277 insn = NEXT_INSN (insn);
7281 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7282 be running after reorg, SEQUENCE rtl is possible. */
7285 contains (rtx insn, varray_type vec)
7289 if (GET_CODE (insn) == INSN
7290 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7293 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7294 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7295 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7301 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7302 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7309 prologue_epilogue_contains (rtx insn)
7311 if (contains (insn, prologue))
7313 if (contains (insn, epilogue))
7319 sibcall_epilogue_contains (rtx insn)
7321 if (sibcall_epilogue)
7322 return contains (insn, sibcall_epilogue);
7327 /* Insert gen_return at the end of block BB. This also means updating
7328 block_for_insn appropriately. */
7331 emit_return_into_block (basic_block bb, rtx line_note)
7333 emit_jump_insn_after (gen_return (), BB_END (bb));
7335 emit_note_copy_after (line_note, PREV_INSN (BB_END (bb)));
7337 #endif /* HAVE_return */
7339 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7341 /* These functions convert the epilogue into a variant that does not modify the
7342 stack pointer. This is used in cases where a function returns an object
7343 whose size is not known until it is computed. The called function leaves the
7344 object on the stack, leaves the stack depressed, and returns a pointer to
7347 What we need to do is track all modifications and references to the stack
7348 pointer, deleting the modifications and changing the references to point to
7349 the location the stack pointer would have pointed to had the modifications
7352 These functions need to be portable so we need to make as few assumptions
7353 about the epilogue as we can. However, the epilogue basically contains
7354 three things: instructions to reset the stack pointer, instructions to
7355 reload registers, possibly including the frame pointer, and an
7356 instruction to return to the caller.
7358 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7359 We also make no attempt to validate the insns we make since if they are
7360 invalid, we probably can't do anything valid. The intent is that these
7361 routines get "smarter" as more and more machines start to use them and
7362 they try operating on different epilogues.
7364 We use the following structure to track what the part of the epilogue that
7365 we've already processed has done. We keep two copies of the SP equivalence,
7366 one for use during the insn we are processing and one for use in the next
7367 insn. The difference is because one part of a PARALLEL may adjust SP
7368 and the other may use it. */
7372 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7373 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7374 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7375 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7376 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7377 should be set to once we no longer need
7379 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences
7383 static void handle_epilogue_set (rtx, struct epi_info *);
7384 static void update_epilogue_consts (rtx, rtx, void *);
7385 static void emit_equiv_load (struct epi_info *);
7387 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7388 no modifications to the stack pointer. Return the new list of insns. */
7391 keep_stack_depressed (rtx insns)
7394 struct epi_info info;
7397 /* If the epilogue is just a single instruction, it must be OK as is. */
7398 if (NEXT_INSN (insns) == NULL_RTX)
7401 /* Otherwise, start a sequence, initialize the information we have, and
7402 process all the insns we were given. */
7405 info.sp_equiv_reg = stack_pointer_rtx;
7407 info.equiv_reg_src = 0;
7409 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
7410 info.const_equiv[j] = 0;
7414 while (insn != NULL_RTX)
7416 next = NEXT_INSN (insn);
7425 /* If this insn references the register that SP is equivalent to and
7426 we have a pending load to that register, we must force out the load
7427 first and then indicate we no longer know what SP's equivalent is. */
7428 if (info.equiv_reg_src != 0
7429 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7431 emit_equiv_load (&info);
7432 info.sp_equiv_reg = 0;
7435 info.new_sp_equiv_reg = info.sp_equiv_reg;
7436 info.new_sp_offset = info.sp_offset;
7438 /* If this is a (RETURN) and the return address is on the stack,
7439 update the address and change to an indirect jump. */
7440 if (GET_CODE (PATTERN (insn)) == RETURN
7441 || (GET_CODE (PATTERN (insn)) == PARALLEL
7442 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7444 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7446 HOST_WIDE_INT offset = 0;
7447 rtx jump_insn, jump_set;
7449 /* If the return address is in a register, we can emit the insn
7450 unchanged. Otherwise, it must be a MEM and we see what the
7451 base register and offset are. In any case, we have to emit any
7452 pending load to the equivalent reg of SP, if any. */
7453 if (GET_CODE (retaddr) == REG)
7455 emit_equiv_load (&info);
7460 else if (GET_CODE (retaddr) == MEM
7461 && GET_CODE (XEXP (retaddr, 0)) == REG)
7462 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7463 else if (GET_CODE (retaddr) == MEM
7464 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7465 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7466 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7468 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7469 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7474 /* If the base of the location containing the return pointer
7475 is SP, we must update it with the replacement address. Otherwise,
7476 just build the necessary MEM. */
7477 retaddr = plus_constant (base, offset);
7478 if (base == stack_pointer_rtx)
7479 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7480 plus_constant (info.sp_equiv_reg,
7483 retaddr = gen_rtx_MEM (Pmode, retaddr);
7485 /* If there is a pending load to the equivalent register for SP
7486 and we reference that register, we must load our address into
7487 a scratch register and then do that load. */
7488 if (info.equiv_reg_src
7489 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7494 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7495 if (HARD_REGNO_MODE_OK (regno, Pmode)
7496 && !fixed_regs[regno]
7497 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7498 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7500 && !refers_to_regno_p (regno,
7501 regno + hard_regno_nregs[regno]
7503 info.equiv_reg_src, NULL)
7504 && info.const_equiv[regno] == 0)
7507 if (regno == FIRST_PSEUDO_REGISTER)
7510 reg = gen_rtx_REG (Pmode, regno);
7511 emit_move_insn (reg, retaddr);
7515 emit_equiv_load (&info);
7516 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7518 /* Show the SET in the above insn is a RETURN. */
7519 jump_set = single_set (jump_insn);
7523 SET_IS_RETURN_P (jump_set) = 1;
7526 /* If SP is not mentioned in the pattern and its equivalent register, if
7527 any, is not modified, just emit it. Otherwise, if neither is set,
7528 replace the reference to SP and emit the insn. If none of those are
7529 true, handle each SET individually. */
7530 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7531 && (info.sp_equiv_reg == stack_pointer_rtx
7532 || !reg_set_p (info.sp_equiv_reg, insn)))
7534 else if (! reg_set_p (stack_pointer_rtx, insn)
7535 && (info.sp_equiv_reg == stack_pointer_rtx
7536 || !reg_set_p (info.sp_equiv_reg, insn)))
7538 if (! validate_replace_rtx (stack_pointer_rtx,
7539 plus_constant (info.sp_equiv_reg,
7546 else if (GET_CODE (PATTERN (insn)) == SET)
7547 handle_epilogue_set (PATTERN (insn), &info);
7548 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7550 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7551 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7552 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7557 info.sp_equiv_reg = info.new_sp_equiv_reg;
7558 info.sp_offset = info.new_sp_offset;
7560 /* Now update any constants this insn sets. */
7561 note_stores (PATTERN (insn), update_epilogue_consts, &info);
7565 insns = get_insns ();
7570 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7571 structure that contains information about what we've seen so far. We
7572 process this SET by either updating that data or by emitting one or
7576 handle_epilogue_set (rtx set, struct epi_info *p)
7578 /* First handle the case where we are setting SP. Record what it is being
7579 set from. If unknown, abort. */
7580 if (reg_set_p (stack_pointer_rtx, set))
7582 if (SET_DEST (set) != stack_pointer_rtx)
7585 if (GET_CODE (SET_SRC (set)) == PLUS)
7587 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7588 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7589 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7590 else if (GET_CODE (XEXP (SET_SRC (set), 1)) == REG
7591 && REGNO (XEXP (SET_SRC (set), 1)) < FIRST_PSEUDO_REGISTER
7592 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))] != 0)
7594 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
7599 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7601 /* If we are adjusting SP, we adjust from the old data. */
7602 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7604 p->new_sp_equiv_reg = p->sp_equiv_reg;
7605 p->new_sp_offset += p->sp_offset;
7608 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7614 /* Next handle the case where we are setting SP's equivalent register.
7615 If we already have a value to set it to, abort. We could update, but
7616 there seems little point in handling that case. Note that we have
7617 to allow for the case where we are setting the register set in
7618 the previous part of a PARALLEL inside a single insn. But use the
7619 old offset for any updates within this insn. We must allow for the case
7620 where the register is being set in a different (usually wider) mode than
7622 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7624 if (p->equiv_reg_src != 0
7625 || GET_CODE (p->new_sp_equiv_reg) != REG
7626 || GET_CODE (SET_DEST (set)) != REG
7627 || GET_MODE_BITSIZE (GET_MODE (SET_DEST (set))) > BITS_PER_WORD
7628 || REGNO (p->new_sp_equiv_reg) != REGNO (SET_DEST (set)))
7632 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7633 plus_constant (p->sp_equiv_reg,
7637 /* Otherwise, replace any references to SP in the insn to its new value
7638 and emit the insn. */
7641 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7642 plus_constant (p->sp_equiv_reg,
7644 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7645 plus_constant (p->sp_equiv_reg,
7651 /* Update the tracking information for registers set to constants. */
7654 update_epilogue_consts (rtx dest, rtx x, void *data)
7656 struct epi_info *p = (struct epi_info *) data;
7659 if (GET_CODE (dest) != REG || REGNO (dest) >= FIRST_PSEUDO_REGISTER)
7662 /* If we are either clobbering a register or doing a partial set,
7663 show we don't know the value. */
7664 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x)))
7665 p->const_equiv[REGNO (dest)] = 0;
7667 /* If we are setting it to a constant, record that constant. */
7668 else if (GET_CODE (SET_SRC (x)) == CONST_INT)
7669 p->const_equiv[REGNO (dest)] = SET_SRC (x);
7671 /* If this is a binary operation between a register we have been tracking
7672 and a constant, see if we can compute a new constant value. */
7673 else if ((GET_RTX_CLASS (GET_CODE (SET_SRC (x))) == 'c'
7674 || GET_RTX_CLASS (GET_CODE (SET_SRC (x))) == '2')
7675 && GET_CODE (XEXP (SET_SRC (x), 0)) == REG
7676 && REGNO (XEXP (SET_SRC (x), 0)) < FIRST_PSEUDO_REGISTER
7677 && p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))] != 0
7678 && GET_CODE (XEXP (SET_SRC (x), 1)) == CONST_INT
7679 && 0 != (new = simplify_binary_operation
7680 (GET_CODE (SET_SRC (x)), GET_MODE (dest),
7681 p->const_equiv[REGNO (XEXP (SET_SRC (x), 0))],
7682 XEXP (SET_SRC (x), 1)))
7683 && GET_CODE (new) == CONST_INT)
7684 p->const_equiv[REGNO (dest)] = new;
7686 /* Otherwise, we can't do anything with this value. */
7688 p->const_equiv[REGNO (dest)] = 0;
7691 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7694 emit_equiv_load (struct epi_info *p)
7696 if (p->equiv_reg_src != 0)
7698 rtx dest = p->sp_equiv_reg;
7700 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest))
7701 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src),
7702 REGNO (p->sp_equiv_reg));
7704 emit_move_insn (dest, p->equiv_reg_src);
7705 p->equiv_reg_src = 0;
7710 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7711 this into place with notes indicating where the prologue ends and where
7712 the epilogue begins. Update the basic block information when possible. */
7715 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
7719 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7722 #ifdef HAVE_prologue
7723 rtx prologue_end = NULL_RTX;
7725 #if defined (HAVE_epilogue) || defined(HAVE_return)
7726 rtx epilogue_end = NULL_RTX;
7729 #ifdef HAVE_prologue
7733 seq = gen_prologue ();
7736 /* Retain a map of the prologue insns. */
7737 record_insns (seq, &prologue);
7738 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
7742 set_insn_locators (seq, prologue_locator);
7744 /* Can't deal with multiple successors of the entry block
7745 at the moment. Function should always have at least one
7747 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7750 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7755 /* If the exit block has no non-fake predecessors, we don't need
7757 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7758 if ((e->flags & EDGE_FAKE) == 0)
7764 if (optimize && HAVE_return)
7766 /* If we're allowed to generate a simple return instruction,
7767 then by definition we don't need a full epilogue. Examine
7768 the block that falls through to EXIT. If it does not
7769 contain any code, examine its predecessors and try to
7770 emit (conditional) return instructions. */
7776 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7777 if (e->flags & EDGE_FALLTHRU)
7783 /* Verify that there are no active instructions in the last block. */
7784 label = BB_END (last);
7785 while (label && GET_CODE (label) != CODE_LABEL)
7787 if (active_insn_p (label))
7789 label = PREV_INSN (label);
7792 if (BB_HEAD (last) == label && GET_CODE (label) == CODE_LABEL)
7794 rtx epilogue_line_note = NULL_RTX;
7796 /* Locate the line number associated with the closing brace,
7797 if we can find one. */
7798 for (seq = get_last_insn ();
7799 seq && ! active_insn_p (seq);
7800 seq = PREV_INSN (seq))
7801 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7803 epilogue_line_note = seq;
7807 for (e = last->pred; e; e = e_next)
7809 basic_block bb = e->src;
7812 e_next = e->pred_next;
7813 if (bb == ENTRY_BLOCK_PTR)
7817 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7820 /* If we have an unconditional jump, we can replace that
7821 with a simple return instruction. */
7822 if (simplejump_p (jump))
7824 emit_return_into_block (bb, epilogue_line_note);
7828 /* If we have a conditional jump, we can try to replace
7829 that with a conditional return instruction. */
7830 else if (condjump_p (jump))
7832 if (! redirect_jump (jump, 0, 0))
7835 /* If this block has only one successor, it both jumps
7836 and falls through to the fallthru block, so we can't
7838 if (bb->succ->succ_next == NULL)
7844 /* Fix up the CFG for the successful change we just made. */
7845 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7848 /* Emit a return insn for the exit fallthru block. Whether
7849 this is still reachable will be determined later. */
7851 emit_barrier_after (BB_END (last));
7852 emit_return_into_block (last, epilogue_line_note);
7853 epilogue_end = BB_END (last);
7854 last->succ->flags &= ~EDGE_FALLTHRU;
7859 #ifdef HAVE_epilogue
7862 /* Find the edge that falls through to EXIT. Other edges may exist
7863 due to RETURN instructions, but those don't need epilogues.
7864 There really shouldn't be a mixture -- either all should have
7865 been converted or none, however... */
7867 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7868 if (e->flags & EDGE_FALLTHRU)
7874 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
7876 seq = gen_epilogue ();
7878 #ifdef INCOMING_RETURN_ADDR_RTX
7879 /* If this function returns with the stack depressed and we can support
7880 it, massage the epilogue to actually do that. */
7881 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7882 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7883 seq = keep_stack_depressed (seq);
7886 emit_jump_insn (seq);
7888 /* Retain a map of the epilogue insns. */
7889 record_insns (seq, &epilogue);
7890 set_insn_locators (seq, epilogue_locator);
7895 insert_insn_on_edge (seq, e);
7902 commit_edge_insertions ();
7904 #ifdef HAVE_sibcall_epilogue
7905 /* Emit sibling epilogues before any sibling call sites. */
7906 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7908 basic_block bb = e->src;
7909 rtx insn = BB_END (bb);
7913 if (GET_CODE (insn) != CALL_INSN
7914 || ! SIBLING_CALL_P (insn))
7918 emit_insn (gen_sibcall_epilogue ());
7922 /* Retain a map of the epilogue insns. Used in life analysis to
7923 avoid getting rid of sibcall epilogue insns. Do this before we
7924 actually emit the sequence. */
7925 record_insns (seq, &sibcall_epilogue);
7926 set_insn_locators (seq, epilogue_locator);
7928 i = PREV_INSN (insn);
7929 newinsn = emit_insn_before (seq, insn);
7933 #ifdef HAVE_prologue
7934 /* This is probably all useless now that we use locators. */
7939 /* GDB handles `break f' by setting a breakpoint on the first
7940 line note after the prologue. Which means (1) that if
7941 there are line number notes before where we inserted the
7942 prologue we should move them, and (2) we should generate a
7943 note before the end of the first basic block, if there isn't
7946 ??? This behavior is completely broken when dealing with
7947 multiple entry functions. We simply place the note always
7948 into first basic block and let alternate entry points
7952 for (insn = prologue_end; insn; insn = prev)
7954 prev = PREV_INSN (insn);
7955 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7957 /* Note that we cannot reorder the first insn in the
7958 chain, since rest_of_compilation relies on that
7959 remaining constant. */
7962 reorder_insns (insn, insn, prologue_end);
7966 /* Find the last line number note in the first block. */
7967 for (insn = BB_END (ENTRY_BLOCK_PTR->next_bb);
7968 insn != prologue_end && insn;
7969 insn = PREV_INSN (insn))
7970 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7973 /* If we didn't find one, make a copy of the first line number
7977 for (insn = next_active_insn (prologue_end);
7979 insn = PREV_INSN (insn))
7980 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7982 emit_note_copy_after (insn, prologue_end);
7988 #ifdef HAVE_epilogue
7993 /* Similarly, move any line notes that appear after the epilogue.
7994 There is no need, however, to be quite so anal about the existence
7996 for (insn = epilogue_end; insn; insn = next)
7998 next = NEXT_INSN (insn);
7999 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
8000 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
8006 /* Reposition the prologue-end and epilogue-begin notes after instruction
8007 scheduling and delayed branch scheduling. */
8010 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
8012 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
8013 rtx insn, last, note;
8016 if ((len = VARRAY_SIZE (prologue)) > 0)
8020 /* Scan from the beginning until we reach the last prologue insn.
8021 We apparently can't depend on basic_block_{head,end} after
8023 for (insn = f; insn; insn = NEXT_INSN (insn))
8025 if (GET_CODE (insn) == NOTE)
8027 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
8030 else if (contains (insn, prologue))
8040 /* Find the prologue-end note if we haven't already, and
8041 move it to just after the last prologue insn. */
8044 for (note = last; (note = NEXT_INSN (note));)
8045 if (GET_CODE (note) == NOTE
8046 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
8050 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
8051 if (GET_CODE (last) == CODE_LABEL)
8052 last = NEXT_INSN (last);
8053 reorder_insns (note, note, last);
8057 if ((len = VARRAY_SIZE (epilogue)) > 0)
8061 /* Scan from the end until we reach the first epilogue insn.
8062 We apparently can't depend on basic_block_{head,end} after
8064 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
8066 if (GET_CODE (insn) == NOTE)
8068 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
8071 else if (contains (insn, epilogue))
8081 /* Find the epilogue-begin note if we haven't already, and
8082 move it to just before the first epilogue insn. */
8085 for (note = insn; (note = PREV_INSN (note));)
8086 if (GET_CODE (note) == NOTE
8087 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
8091 if (PREV_INSN (last) != note)
8092 reorder_insns (note, note, PREV_INSN (last));
8095 #endif /* HAVE_prologue or HAVE_epilogue */
8098 /* Called once, at initialization, to initialize function.c. */
8101 init_function_once (void)
8103 VARRAY_INT_INIT (prologue, 0, "prologue");
8104 VARRAY_INT_INIT (epilogue, 0, "epilogue");
8105 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
8108 /* Returns the name of the current function. */
8110 current_function_name (void)
8112 return (*lang_hooks.decl_printable_name) (cfun->decl, 2);
8115 #include "gt-function.h"