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 unsigned int, bool, bool, bool, 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 its 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 -2 means use BITS_PER_UNIT,
510 positive specifies alignment boundary in bits.
512 We do not round to stack_boundary here.
514 FUNCTION specifies the function to allocate in. */
517 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
518 struct function *function)
521 int bigend_correction = 0;
523 int frame_off, frame_alignment, frame_phase;
530 alignment = BIGGEST_ALIGNMENT;
532 alignment = GET_MODE_ALIGNMENT (mode);
534 /* Allow the target to (possibly) increase the alignment of this
536 type = (*lang_hooks.types.type_for_mode) (mode, 0);
538 alignment = LOCAL_ALIGNMENT (type, alignment);
540 alignment /= BITS_PER_UNIT;
542 else if (align == -1)
544 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
545 size = CEIL_ROUND (size, alignment);
547 else if (align == -2)
548 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
550 alignment = align / BITS_PER_UNIT;
552 #ifdef FRAME_GROWS_DOWNWARD
553 function->x_frame_offset -= size;
556 /* Ignore alignment we can't do with expected alignment of the boundary. */
557 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
558 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
560 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
561 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
563 /* Calculate how many bytes the start of local variables is off from
565 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
566 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
567 frame_phase = frame_off ? frame_alignment - frame_off : 0;
569 /* Round the frame offset to the specified alignment. The default is
570 to always honor requests to align the stack but a port may choose to
571 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
572 if (STACK_ALIGNMENT_NEEDED
576 /* We must be careful here, since FRAME_OFFSET might be negative and
577 division with a negative dividend isn't as well defined as we might
578 like. So we instead assume that ALIGNMENT is a power of two and
579 use logical operations which are unambiguous. */
580 #ifdef FRAME_GROWS_DOWNWARD
581 function->x_frame_offset
582 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
585 function->x_frame_offset
586 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
591 /* On a big-endian machine, if we are allocating more space than we will use,
592 use the least significant bytes of those that are allocated. */
593 if (BYTES_BIG_ENDIAN && mode != BLKmode)
594 bigend_correction = size - GET_MODE_SIZE (mode);
596 /* If we have already instantiated virtual registers, return the actual
597 address relative to the frame pointer. */
598 if (function == cfun && virtuals_instantiated)
599 addr = plus_constant (frame_pointer_rtx,
601 (frame_offset + bigend_correction
602 + STARTING_FRAME_OFFSET, Pmode));
604 addr = plus_constant (virtual_stack_vars_rtx,
606 (function->x_frame_offset + bigend_correction,
609 #ifndef FRAME_GROWS_DOWNWARD
610 function->x_frame_offset += size;
613 x = gen_rtx_MEM (mode, addr);
615 function->x_stack_slot_list
616 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
621 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
625 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
627 return assign_stack_local_1 (mode, size, align, cfun);
630 /* Allocate a temporary stack slot and record it for possible later
633 MODE is the machine mode to be given to the returned rtx.
635 SIZE is the size in units of the space required. We do no rounding here
636 since assign_stack_local will do any required rounding.
638 KEEP is 1 if this slot is to be retained after a call to
639 free_temp_slots. Automatic variables for a block are allocated
640 with this flag. KEEP is 2 if we allocate a longer term temporary,
641 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
642 if we are to allocate something at an inner level to be treated as
643 a variable in the block (e.g., a SAVE_EXPR).
645 TYPE is the type that will be used for the stack slot. */
648 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, int keep,
652 struct temp_slot *p, *best_p = 0;
655 /* If SIZE is -1 it means that somebody tried to allocate a temporary
656 of a variable size. */
661 align = BIGGEST_ALIGNMENT;
663 align = GET_MODE_ALIGNMENT (mode);
666 type = (*lang_hooks.types.type_for_mode) (mode, 0);
669 align = LOCAL_ALIGNMENT (type, align);
671 /* Try to find an available, already-allocated temporary of the proper
672 mode which meets the size and alignment requirements. Choose the
673 smallest one with the closest alignment. */
674 for (p = temp_slots; p; p = p->next)
675 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
677 && objects_must_conflict_p (p->type, type)
678 && (best_p == 0 || best_p->size > p->size
679 || (best_p->size == p->size && best_p->align > p->align)))
681 if (p->align == align && p->size == size)
689 /* Make our best, if any, the one to use. */
692 /* If there are enough aligned bytes left over, make them into a new
693 temp_slot so that the extra bytes don't get wasted. Do this only
694 for BLKmode slots, so that we can be sure of the alignment. */
695 if (GET_MODE (best_p->slot) == BLKmode)
697 int alignment = best_p->align / BITS_PER_UNIT;
698 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
700 if (best_p->size - rounded_size >= alignment)
702 p = ggc_alloc (sizeof (struct temp_slot));
703 p->in_use = p->addr_taken = 0;
704 p->size = best_p->size - rounded_size;
705 p->base_offset = best_p->base_offset + rounded_size;
706 p->full_size = best_p->full_size - rounded_size;
707 p->slot = gen_rtx_MEM (BLKmode,
708 plus_constant (XEXP (best_p->slot, 0),
710 p->align = best_p->align;
713 p->type = best_p->type;
714 p->next = temp_slots;
717 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
720 best_p->size = rounded_size;
721 best_p->full_size = rounded_size;
728 /* If we still didn't find one, make a new temporary. */
731 HOST_WIDE_INT frame_offset_old = frame_offset;
733 p = ggc_alloc (sizeof (struct temp_slot));
735 /* We are passing an explicit alignment request to assign_stack_local.
736 One side effect of that is assign_stack_local will not round SIZE
737 to ensure the frame offset remains suitably aligned.
739 So for requests which depended on the rounding of SIZE, we go ahead
740 and round it now. We also make sure ALIGNMENT is at least
741 BIGGEST_ALIGNMENT. */
742 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
744 p->slot = assign_stack_local (mode,
746 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
752 /* The following slot size computation is necessary because we don't
753 know the actual size of the temporary slot until assign_stack_local
754 has performed all the frame alignment and size rounding for the
755 requested temporary. Note that extra space added for alignment
756 can be either above or below this stack slot depending on which
757 way the frame grows. We include the extra space if and only if it
758 is above this slot. */
759 #ifdef FRAME_GROWS_DOWNWARD
760 p->size = frame_offset_old - frame_offset;
765 /* Now define the fields used by combine_temp_slots. */
766 #ifdef FRAME_GROWS_DOWNWARD
767 p->base_offset = frame_offset;
768 p->full_size = frame_offset_old - frame_offset;
770 p->base_offset = frame_offset_old;
771 p->full_size = frame_offset - frame_offset_old;
774 p->next = temp_slots;
780 p->rtl_expr = seq_rtl_expr;
785 p->level = target_temp_slot_level;
790 p->level = var_temp_slot_level;
795 p->level = temp_slot_level;
800 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
801 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
802 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
804 /* If we know the alias set for the memory that will be used, use
805 it. If there's no TYPE, then we don't know anything about the
806 alias set for the memory. */
807 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
808 set_mem_align (slot, align);
810 /* If a type is specified, set the relevant flags. */
813 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
814 && TYPE_READONLY (type));
815 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
816 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
822 /* Allocate a temporary stack slot and record it for possible later
823 reuse. First three arguments are same as in preceding function. */
826 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
828 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
831 /* Assign a temporary.
832 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
833 and so that should be used in error messages. In either case, we
834 allocate of the given type.
835 KEEP is as for assign_stack_temp.
836 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
837 it is 0 if a register is OK.
838 DONT_PROMOTE is 1 if we should not promote values in register
842 assign_temp (tree type_or_decl, int keep, int memory_required,
843 int dont_promote ATTRIBUTE_UNUSED)
846 enum machine_mode mode;
847 #ifndef PROMOTE_FOR_CALL_ONLY
851 if (DECL_P (type_or_decl))
852 decl = type_or_decl, type = TREE_TYPE (decl);
854 decl = NULL, type = type_or_decl;
856 mode = TYPE_MODE (type);
857 #ifndef PROMOTE_FOR_CALL_ONLY
858 unsignedp = TREE_UNSIGNED (type);
861 if (mode == BLKmode || memory_required)
863 HOST_WIDE_INT size = int_size_in_bytes (type);
866 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
867 problems with allocating the stack space. */
871 /* Unfortunately, we don't yet know how to allocate variable-sized
872 temporaries. However, sometimes we have a fixed upper limit on
873 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
874 instead. This is the case for Chill variable-sized strings. */
875 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
876 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
877 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
878 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
880 /* The size of the temporary may be too large to fit into an integer. */
881 /* ??? Not sure this should happen except for user silliness, so limit
882 this to things that aren't compiler-generated temporaries. The
883 rest of the time we'll abort in assign_stack_temp_for_type. */
884 if (decl && size == -1
885 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
887 error ("%Jsize of variable '%D' is too large", decl, decl);
891 tmp = assign_stack_temp_for_type (mode, size, keep, type);
895 #ifndef PROMOTE_FOR_CALL_ONLY
897 mode = promote_mode (type, mode, &unsignedp, 0);
900 return gen_reg_rtx (mode);
903 /* Combine temporary stack slots which are adjacent on the stack.
905 This allows for better use of already allocated stack space. This is only
906 done for BLKmode slots because we can be sure that we won't have alignment
907 problems in this case. */
910 combine_temp_slots (void)
912 struct temp_slot *p, *q;
913 struct temp_slot *prev_p, *prev_q;
916 /* We can't combine slots, because the information about which slot
917 is in which alias set will be lost. */
918 if (flag_strict_aliasing)
921 /* If there are a lot of temp slots, don't do anything unless
922 high levels of optimization. */
923 if (! flag_expensive_optimizations)
924 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
925 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
928 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
932 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
933 for (q = p->next, prev_q = p; q; q = prev_q->next)
936 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
938 if (p->base_offset + p->full_size == q->base_offset)
940 /* Q comes after P; combine Q into P. */
942 p->full_size += q->full_size;
945 else if (q->base_offset + q->full_size == p->base_offset)
947 /* P comes after Q; combine P into Q. */
949 q->full_size += p->full_size;
954 /* Either delete Q or advance past it. */
956 prev_q->next = q->next;
960 /* Either delete P or advance past it. */
964 prev_p->next = p->next;
966 temp_slots = p->next;
973 /* Find the temp slot corresponding to the object at address X. */
975 static struct temp_slot *
976 find_temp_slot_from_address (rtx x)
981 for (p = temp_slots; p; p = p->next)
986 else if (XEXP (p->slot, 0) == x
988 || (GET_CODE (x) == PLUS
989 && XEXP (x, 0) == virtual_stack_vars_rtx
990 && GET_CODE (XEXP (x, 1)) == CONST_INT
991 && INTVAL (XEXP (x, 1)) >= p->base_offset
992 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
995 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
996 for (next = p->address; next; next = XEXP (next, 1))
997 if (XEXP (next, 0) == x)
1001 /* If we have a sum involving a register, see if it points to a temp
1003 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1004 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1006 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1007 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1013 /* Indicate that NEW is an alternate way of referring to the temp slot
1014 that previously was known by OLD. */
1017 update_temp_slot_address (rtx old, rtx new)
1019 struct temp_slot *p;
1021 if (rtx_equal_p (old, new))
1024 p = find_temp_slot_from_address (old);
1026 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1027 is a register, see if one operand of the PLUS is a temporary
1028 location. If so, NEW points into it. Otherwise, if both OLD and
1029 NEW are a PLUS and if there is a register in common between them.
1030 If so, try a recursive call on those values. */
1033 if (GET_CODE (old) != PLUS)
1036 if (GET_CODE (new) == REG)
1038 update_temp_slot_address (XEXP (old, 0), new);
1039 update_temp_slot_address (XEXP (old, 1), new);
1042 else if (GET_CODE (new) != PLUS)
1045 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1046 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1047 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1048 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1049 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1050 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1051 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1052 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1057 /* Otherwise add an alias for the temp's address. */
1058 else if (p->address == 0)
1062 if (GET_CODE (p->address) != EXPR_LIST)
1063 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1065 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1069 /* If X could be a reference to a temporary slot, mark the fact that its
1070 address was taken. */
1073 mark_temp_addr_taken (rtx x)
1075 struct temp_slot *p;
1080 /* If X is not in memory or is at a constant address, it cannot be in
1081 a temporary slot. */
1082 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1085 p = find_temp_slot_from_address (XEXP (x, 0));
1090 /* If X could be a reference to a temporary slot, mark that slot as
1091 belonging to the to one level higher than the current level. If X
1092 matched one of our slots, just mark that one. Otherwise, we can't
1093 easily predict which it is, so upgrade all of them. Kept slots
1094 need not be touched.
1096 This is called when an ({...}) construct occurs and a statement
1097 returns a value in memory. */
1100 preserve_temp_slots (rtx x)
1102 struct temp_slot *p = 0;
1104 /* If there is no result, we still might have some objects whose address
1105 were taken, so we need to make sure they stay around. */
1108 for (p = temp_slots; p; p = p->next)
1109 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1115 /* If X is a register that is being used as a pointer, see if we have
1116 a temporary slot we know it points to. To be consistent with
1117 the code below, we really should preserve all non-kept slots
1118 if we can't find a match, but that seems to be much too costly. */
1119 if (GET_CODE (x) == REG && REG_POINTER (x))
1120 p = find_temp_slot_from_address (x);
1122 /* If X is not in memory or is at a constant address, it cannot be in
1123 a temporary slot, but it can contain something whose address was
1125 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1127 for (p = temp_slots; p; p = p->next)
1128 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1134 /* First see if we can find a match. */
1136 p = find_temp_slot_from_address (XEXP (x, 0));
1140 /* Move everything at our level whose address was taken to our new
1141 level in case we used its address. */
1142 struct temp_slot *q;
1144 if (p->level == temp_slot_level)
1146 for (q = temp_slots; q; q = q->next)
1147 if (q != p && q->addr_taken && q->level == p->level)
1156 /* Otherwise, preserve all non-kept slots at this level. */
1157 for (p = temp_slots; p; p = p->next)
1158 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1162 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1163 with that RTL_EXPR, promote it into a temporary slot at the present
1164 level so it will not be freed when we free slots made in the
1168 preserve_rtl_expr_result (rtx x)
1170 struct temp_slot *p;
1172 /* If X is not in memory or is at a constant address, it cannot be in
1173 a temporary slot. */
1174 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1177 /* If we can find a match, move it to our level unless it is already at
1179 p = find_temp_slot_from_address (XEXP (x, 0));
1182 p->level = MIN (p->level, temp_slot_level);
1189 /* Free all temporaries used so far. This is normally called at the end
1190 of generating code for a statement. Don't free any temporaries
1191 currently in use for an RTL_EXPR that hasn't yet been emitted.
1192 We could eventually do better than this since it can be reused while
1193 generating the same RTL_EXPR, but this is complex and probably not
1197 free_temp_slots (void)
1199 struct temp_slot *p;
1201 for (p = temp_slots; p; p = p->next)
1202 if (p->in_use && p->level == temp_slot_level && ! p->keep
1203 && p->rtl_expr == 0)
1206 combine_temp_slots ();
1209 /* Free all temporary slots used in T, an RTL_EXPR node. */
1212 free_temps_for_rtl_expr (tree t)
1214 struct temp_slot *p;
1216 for (p = temp_slots; p; p = p->next)
1217 if (p->rtl_expr == t)
1219 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1220 needs to be preserved. This can happen if a temporary in
1221 the RTL_EXPR was addressed; preserve_temp_slots will move
1222 the temporary into a higher level. */
1223 if (temp_slot_level <= p->level)
1226 p->rtl_expr = NULL_TREE;
1229 combine_temp_slots ();
1232 /* Mark all temporaries ever allocated in this function as not suitable
1233 for reuse until the current level is exited. */
1236 mark_all_temps_used (void)
1238 struct temp_slot *p;
1240 for (p = temp_slots; p; p = p->next)
1242 p->in_use = p->keep = 1;
1243 p->level = MIN (p->level, temp_slot_level);
1247 /* Push deeper into the nesting level for stack temporaries. */
1250 push_temp_slots (void)
1255 /* Pop a temporary nesting level. All slots in use in the current level
1259 pop_temp_slots (void)
1261 struct temp_slot *p;
1263 for (p = temp_slots; p; p = p->next)
1264 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1267 combine_temp_slots ();
1272 /* Initialize temporary slots. */
1275 init_temp_slots (void)
1277 /* We have not allocated any temporaries yet. */
1279 temp_slot_level = 0;
1280 var_temp_slot_level = 0;
1281 target_temp_slot_level = 0;
1284 /* Retroactively move an auto variable from a register to a stack
1285 slot. This is done when an address-reference to the variable is
1286 seen. If RESCAN is true, all previously emitted instructions are
1287 examined and modified to handle the fact that DECL is now
1291 put_var_into_stack (tree decl, int rescan)
1294 enum machine_mode promoted_mode, decl_mode;
1295 struct function *function = 0;
1297 bool can_use_addressof_p;
1298 bool volatile_p = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1299 bool used_p = (TREE_USED (decl)
1300 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1302 context = decl_function_context (decl);
1304 /* Get the current rtl used for this object and its original mode. */
1305 reg = (TREE_CODE (decl) == SAVE_EXPR
1306 ? SAVE_EXPR_RTL (decl)
1307 : DECL_RTL_IF_SET (decl));
1309 /* No need to do anything if decl has no rtx yet
1310 since in that case caller is setting TREE_ADDRESSABLE
1311 and a stack slot will be assigned when the rtl is made. */
1315 /* Get the declared mode for this object. */
1316 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1317 : DECL_MODE (decl));
1318 /* Get the mode it's actually stored in. */
1319 promoted_mode = GET_MODE (reg);
1321 /* If this variable comes from an outer function, find that
1322 function's saved context. Don't use find_function_data here,
1323 because it might not be in any active function.
1324 FIXME: Is that really supposed to happen?
1325 It does in ObjC at least. */
1326 if (context != current_function_decl && context != inline_function_decl)
1327 for (function = outer_function_chain; function; function = function->outer)
1328 if (function->decl == context)
1331 /* If this is a variable-sized object or a structure passed by invisible
1332 reference, with a pseudo to address it, put that pseudo into the stack
1333 if the var is non-local. */
1334 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1335 && GET_CODE (reg) == MEM
1336 && GET_CODE (XEXP (reg, 0)) == REG
1337 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1339 reg = XEXP (reg, 0);
1340 decl_mode = promoted_mode = GET_MODE (reg);
1343 /* If this variable lives in the current function and we don't need to put it
1344 in the stack for the sake of setjmp or the non-locality, try to keep it in
1345 a register until we know we actually need the address. */
1348 && ! (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl))
1350 /* FIXME make it work for promoted modes too */
1351 && decl_mode == promoted_mode
1352 #ifdef NON_SAVING_SETJMP
1353 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1357 /* If we can't use ADDRESSOF, make sure we see through one we already
1359 if (! can_use_addressof_p
1360 && GET_CODE (reg) == MEM
1361 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1362 reg = XEXP (XEXP (reg, 0), 0);
1364 /* Now we should have a value that resides in one or more pseudo regs. */
1366 if (GET_CODE (reg) == REG)
1368 if (can_use_addressof_p)
1369 gen_mem_addressof (reg, decl, rescan);
1371 put_reg_into_stack (function, reg, TREE_TYPE (decl), decl_mode,
1372 0, volatile_p, used_p, false, 0);
1374 else if (GET_CODE (reg) == CONCAT)
1376 /* A CONCAT contains two pseudos; put them both in the stack.
1377 We do it so they end up consecutive.
1378 We fixup references to the parts only after we fixup references
1379 to the whole CONCAT, lest we do double fixups for the latter
1381 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1382 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1383 rtx lopart = XEXP (reg, 0);
1384 rtx hipart = XEXP (reg, 1);
1385 #ifdef FRAME_GROWS_DOWNWARD
1386 /* Since part 0 should have a lower address, do it second. */
1387 put_reg_into_stack (function, hipart, part_type, part_mode,
1388 0, volatile_p, false, false, 0);
1389 put_reg_into_stack (function, lopart, part_type, part_mode,
1390 0, volatile_p, false, true, 0);
1392 put_reg_into_stack (function, lopart, part_type, part_mode,
1393 0, volatile_p, false, false, 0);
1394 put_reg_into_stack (function, hipart, part_type, part_mode,
1395 0, volatile_p, false, true, 0);
1398 /* Change the CONCAT into a combined MEM for both parts. */
1399 PUT_CODE (reg, MEM);
1400 MEM_ATTRS (reg) = 0;
1402 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1403 already computed alias sets. Here we want to re-generate. */
1405 SET_DECL_RTL (decl, NULL);
1406 set_mem_attributes (reg, decl, 1);
1408 SET_DECL_RTL (decl, reg);
1410 /* The two parts are in memory order already.
1411 Use the lower parts address as ours. */
1412 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1413 /* Prevent sharing of rtl that might lose. */
1414 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1415 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1416 if (used_p && rescan)
1418 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1420 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1421 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1428 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1429 into the stack frame of FUNCTION (0 means the current function).
1430 TYPE is the user-level data type of the value hold in the register.
1431 DECL_MODE is the machine mode of the user-level data type.
1432 ORIGINAL_REGNO must be set if the real regno is not visible in REG.
1433 VOLATILE_P is true if this is for a "volatile" decl.
1434 USED_P is true if this reg might have already been used in an insn.
1435 CONSECUTIVE_P is true if the stack slot assigned to reg must be
1436 consecutive with the previous stack slot. */
1439 put_reg_into_stack (struct function *function, rtx reg, tree type,
1440 enum machine_mode decl_mode, unsigned int original_regno,
1441 bool volatile_p, bool used_p, bool consecutive_p,
1444 struct function *func = function ? function : cfun;
1445 enum machine_mode mode = GET_MODE (reg);
1446 unsigned int regno = original_regno;
1450 regno = REGNO (reg);
1452 if (regno < func->x_max_parm_reg)
1454 if (!func->x_parm_reg_stack_loc)
1456 new = func->x_parm_reg_stack_loc[regno];
1460 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode),
1461 consecutive_p ? -2 : 0, func);
1463 PUT_CODE (reg, MEM);
1464 PUT_MODE (reg, decl_mode);
1465 XEXP (reg, 0) = XEXP (new, 0);
1466 MEM_ATTRS (reg) = 0;
1467 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1468 MEM_VOLATILE_P (reg) = volatile_p;
1470 /* If this is a memory ref that contains aggregate components,
1471 mark it as such for cse and loop optimize. If we are reusing a
1472 previously generated stack slot, then we need to copy the bit in
1473 case it was set for other reasons. For instance, it is set for
1474 __builtin_va_alist. */
1477 MEM_SET_IN_STRUCT_P (reg,
1478 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1479 set_mem_alias_set (reg, get_alias_set (type));
1483 schedule_fixup_var_refs (function, reg, type, mode, ht);
1486 /* Make sure that all refs to the variable, previously made
1487 when it was a register, are fixed up to be valid again.
1488 See function above for meaning of arguments. */
1491 schedule_fixup_var_refs (struct function *function, rtx reg, tree type,
1492 enum machine_mode promoted_mode, htab_t ht)
1494 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1498 struct var_refs_queue *temp;
1500 temp = ggc_alloc (sizeof (struct var_refs_queue));
1501 temp->modified = reg;
1502 temp->promoted_mode = promoted_mode;
1503 temp->unsignedp = unsigned_p;
1504 temp->next = function->fixup_var_refs_queue;
1505 function->fixup_var_refs_queue = temp;
1508 /* Variable is local; fix it up now. */
1509 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1513 fixup_var_refs (rtx var, enum machine_mode promoted_mode, int unsignedp,
1514 rtx may_share, htab_t ht)
1517 rtx first_insn = get_insns ();
1518 struct sequence_stack *stack = seq_stack;
1519 tree rtl_exps = rtl_expr_chain;
1521 /* If there's a hash table, it must record all uses of VAR. */
1526 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1531 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1532 stack == 0, may_share);
1534 /* Scan all pending sequences too. */
1535 for (; stack; stack = stack->next)
1537 push_to_full_sequence (stack->first, stack->last);
1538 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1539 stack->next != 0, may_share);
1540 /* Update remembered end of sequence
1541 in case we added an insn at the end. */
1542 stack->last = get_last_insn ();
1546 /* Scan all waiting RTL_EXPRs too. */
1547 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1549 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1550 if (seq != const0_rtx && seq != 0)
1552 push_to_sequence (seq);
1553 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1560 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1561 some part of an insn. Return a struct fixup_replacement whose OLD
1562 value is equal to X. Allocate a new structure if no such entry exists. */
1564 static struct fixup_replacement *
1565 find_fixup_replacement (struct fixup_replacement **replacements, rtx x)
1567 struct fixup_replacement *p;
1569 /* See if we have already replaced this. */
1570 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1575 p = xmalloc (sizeof (struct fixup_replacement));
1578 p->next = *replacements;
1585 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1586 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1587 for the current function. MAY_SHARE is either a MEM that is not
1588 to be unshared or a list of them. */
1591 fixup_var_refs_insns (rtx insn, rtx var, enum machine_mode promoted_mode,
1592 int unsignedp, int toplevel, rtx may_share)
1596 /* fixup_var_refs_insn might modify insn, so save its next
1598 rtx next = NEXT_INSN (insn);
1600 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1601 the three sequences they (potentially) contain, and process
1602 them recursively. The CALL_INSN itself is not interesting. */
1604 if (GET_CODE (insn) == CALL_INSN
1605 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1609 /* Look at the Normal call, sibling call and tail recursion
1610 sequences attached to the CALL_PLACEHOLDER. */
1611 for (i = 0; i < 3; i++)
1613 rtx seq = XEXP (PATTERN (insn), i);
1616 push_to_sequence (seq);
1617 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1619 XEXP (PATTERN (insn), i) = get_insns ();
1625 else if (INSN_P (insn))
1626 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1633 /* Look up the insns which reference VAR in HT and fix them up. Other
1634 arguments are the same as fixup_var_refs_insns.
1636 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1637 because the hash table will point straight to the interesting insn
1638 (inside the CALL_PLACEHOLDER). */
1641 fixup_var_refs_insns_with_hash (htab_t ht, rtx var, enum machine_mode promoted_mode,
1642 int unsignedp, rtx may_share)
1644 struct insns_for_mem_entry tmp;
1645 struct insns_for_mem_entry *ime;
1649 ime = htab_find (ht, &tmp);
1650 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1651 if (INSN_P (XEXP (insn_list, 0)) && !INSN_DELETED_P (XEXP (insn_list, 0)))
1652 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1653 unsignedp, 1, may_share);
1657 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1658 the insn under examination, VAR is the variable to fix up
1659 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1660 TOPLEVEL is nonzero if this is the main insn chain for this
1664 fixup_var_refs_insn (rtx insn, rtx var, enum machine_mode promoted_mode,
1665 int unsignedp, int toplevel, rtx no_share)
1668 rtx set, prev, prev_set;
1671 /* Remember the notes in case we delete the insn. */
1672 note = REG_NOTES (insn);
1674 /* If this is a CLOBBER of VAR, delete it.
1676 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1677 and REG_RETVAL notes too. */
1678 if (GET_CODE (PATTERN (insn)) == CLOBBER
1679 && (XEXP (PATTERN (insn), 0) == var
1680 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1681 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1682 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1684 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1685 /* The REG_LIBCALL note will go away since we are going to
1686 turn INSN into a NOTE, so just delete the
1687 corresponding REG_RETVAL note. */
1688 remove_note (XEXP (note, 0),
1689 find_reg_note (XEXP (note, 0), REG_RETVAL,
1695 /* The insn to load VAR from a home in the arglist
1696 is now a no-op. When we see it, just delete it.
1697 Similarly if this is storing VAR from a register from which
1698 it was loaded in the previous insn. This will occur
1699 when an ADDRESSOF was made for an arglist slot. */
1701 && (set = single_set (insn)) != 0
1702 && SET_DEST (set) == var
1703 /* If this represents the result of an insn group,
1704 don't delete the insn. */
1705 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1706 && (rtx_equal_p (SET_SRC (set), var)
1707 || (GET_CODE (SET_SRC (set)) == REG
1708 && (prev = prev_nonnote_insn (insn)) != 0
1709 && (prev_set = single_set (prev)) != 0
1710 && SET_DEST (prev_set) == SET_SRC (set)
1711 && rtx_equal_p (SET_SRC (prev_set), var))))
1717 struct fixup_replacement *replacements = 0;
1718 rtx next_insn = NEXT_INSN (insn);
1720 if (SMALL_REGISTER_CLASSES)
1722 /* If the insn that copies the results of a CALL_INSN
1723 into a pseudo now references VAR, we have to use an
1724 intermediate pseudo since we want the life of the
1725 return value register to be only a single insn.
1727 If we don't use an intermediate pseudo, such things as
1728 address computations to make the address of VAR valid
1729 if it is not can be placed between the CALL_INSN and INSN.
1731 To make sure this doesn't happen, we record the destination
1732 of the CALL_INSN and see if the next insn uses both that
1735 if (call_dest != 0 && GET_CODE (insn) == INSN
1736 && reg_mentioned_p (var, PATTERN (insn))
1737 && reg_mentioned_p (call_dest, PATTERN (insn)))
1739 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1741 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1743 PATTERN (insn) = replace_rtx (PATTERN (insn),
1747 if (GET_CODE (insn) == CALL_INSN
1748 && GET_CODE (PATTERN (insn)) == SET)
1749 call_dest = SET_DEST (PATTERN (insn));
1750 else if (GET_CODE (insn) == CALL_INSN
1751 && GET_CODE (PATTERN (insn)) == PARALLEL
1752 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1753 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1758 /* See if we have to do anything to INSN now that VAR is in
1759 memory. If it needs to be loaded into a pseudo, use a single
1760 pseudo for the entire insn in case there is a MATCH_DUP
1761 between two operands. We pass a pointer to the head of
1762 a list of struct fixup_replacements. If fixup_var_refs_1
1763 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1764 it will record them in this list.
1766 If it allocated a pseudo for any replacement, we copy into
1769 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1770 &replacements, no_share);
1772 /* If this is last_parm_insn, and any instructions were output
1773 after it to fix it up, then we must set last_parm_insn to
1774 the last such instruction emitted. */
1775 if (insn == last_parm_insn)
1776 last_parm_insn = PREV_INSN (next_insn);
1778 while (replacements)
1780 struct fixup_replacement *next;
1782 if (GET_CODE (replacements->new) == REG)
1787 /* OLD might be a (subreg (mem)). */
1788 if (GET_CODE (replacements->old) == SUBREG)
1790 = fixup_memory_subreg (replacements->old, insn,
1794 = fixup_stack_1 (replacements->old, insn);
1796 insert_before = insn;
1798 /* If we are changing the mode, do a conversion.
1799 This might be wasteful, but combine.c will
1800 eliminate much of the waste. */
1802 if (GET_MODE (replacements->new)
1803 != GET_MODE (replacements->old))
1806 convert_move (replacements->new,
1807 replacements->old, unsignedp);
1812 seq = gen_move_insn (replacements->new,
1815 emit_insn_before (seq, insert_before);
1818 next = replacements->next;
1819 free (replacements);
1820 replacements = next;
1824 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1825 But don't touch other insns referred to by reg-notes;
1826 we will get them elsewhere. */
1829 if (GET_CODE (note) != INSN_LIST)
1831 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1833 note = XEXP (note, 1);
1837 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1838 See if the rtx expression at *LOC in INSN needs to be changed.
1840 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1841 contain a list of original rtx's and replacements. If we find that we need
1842 to modify this insn by replacing a memory reference with a pseudo or by
1843 making a new MEM to implement a SUBREG, we consult that list to see if
1844 we have already chosen a replacement. If none has already been allocated,
1845 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1846 or the SUBREG, as appropriate, to the pseudo. */
1849 fixup_var_refs_1 (rtx var, enum machine_mode promoted_mode, rtx *loc, rtx insn,
1850 struct fixup_replacement **replacements, rtx no_share)
1854 RTX_CODE code = GET_CODE (x);
1857 struct fixup_replacement *replacement;
1862 if (XEXP (x, 0) == var)
1864 /* Prevent sharing of rtl that might lose. */
1865 rtx sub = copy_rtx (XEXP (var, 0));
1867 if (! validate_change (insn, loc, sub, 0))
1869 rtx y = gen_reg_rtx (GET_MODE (sub));
1872 /* We should be able to replace with a register or all is lost.
1873 Note that we can't use validate_change to verify this, since
1874 we're not caring for replacing all dups simultaneously. */
1875 if (! validate_replace_rtx (*loc, y, insn))
1878 /* Careful! First try to recognize a direct move of the
1879 value, mimicking how things are done in gen_reload wrt
1880 PLUS. Consider what happens when insn is a conditional
1881 move instruction and addsi3 clobbers flags. */
1884 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1888 if (recog_memoized (new_insn) < 0)
1890 /* That failed. Fall back on force_operand and hope. */
1893 sub = force_operand (sub, y);
1895 emit_insn (gen_move_insn (y, sub));
1901 /* Don't separate setter from user. */
1902 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1903 insn = PREV_INSN (insn);
1906 emit_insn_before (seq, insn);
1914 /* If we already have a replacement, use it. Otherwise,
1915 try to fix up this address in case it is invalid. */
1917 replacement = find_fixup_replacement (replacements, var);
1918 if (replacement->new)
1920 *loc = replacement->new;
1924 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1926 /* Unless we are forcing memory to register or we changed the mode,
1927 we can leave things the way they are if the insn is valid. */
1929 INSN_CODE (insn) = -1;
1930 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1931 && recog_memoized (insn) >= 0)
1934 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1938 /* If X contains VAR, we need to unshare it here so that we update
1939 each occurrence separately. But all identical MEMs in one insn
1940 must be replaced with the same rtx because of the possibility of
1943 if (reg_mentioned_p (var, x))
1945 replacement = find_fixup_replacement (replacements, x);
1946 if (replacement->new == 0)
1947 replacement->new = copy_most_rtx (x, no_share);
1949 *loc = x = replacement->new;
1950 code = GET_CODE (x);
1967 /* Note that in some cases those types of expressions are altered
1968 by optimize_bit_field, and do not survive to get here. */
1969 if (XEXP (x, 0) == var
1970 || (GET_CODE (XEXP (x, 0)) == SUBREG
1971 && SUBREG_REG (XEXP (x, 0)) == var))
1973 /* Get TEM as a valid MEM in the mode presently in the insn.
1975 We don't worry about the possibility of MATCH_DUP here; it
1976 is highly unlikely and would be tricky to handle. */
1979 if (GET_CODE (tem) == SUBREG)
1981 if (GET_MODE_BITSIZE (GET_MODE (tem))
1982 > GET_MODE_BITSIZE (GET_MODE (var)))
1984 replacement = find_fixup_replacement (replacements, var);
1985 if (replacement->new == 0)
1986 replacement->new = gen_reg_rtx (GET_MODE (var));
1987 SUBREG_REG (tem) = replacement->new;
1989 /* The following code works only if we have a MEM, so we
1990 need to handle the subreg here. We directly substitute
1991 it assuming that a subreg must be OK here. We already
1992 scheduled a replacement to copy the mem into the
1998 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2001 tem = fixup_stack_1 (tem, insn);
2003 /* Unless we want to load from memory, get TEM into the proper mode
2004 for an extract from memory. This can only be done if the
2005 extract is at a constant position and length. */
2007 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2008 && GET_CODE (XEXP (x, 2)) == CONST_INT
2009 && ! mode_dependent_address_p (XEXP (tem, 0))
2010 && ! MEM_VOLATILE_P (tem))
2012 enum machine_mode wanted_mode = VOIDmode;
2013 enum machine_mode is_mode = GET_MODE (tem);
2014 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2016 if (GET_CODE (x) == ZERO_EXTRACT)
2018 enum machine_mode new_mode
2019 = mode_for_extraction (EP_extzv, 1);
2020 if (new_mode != MAX_MACHINE_MODE)
2021 wanted_mode = new_mode;
2023 else if (GET_CODE (x) == SIGN_EXTRACT)
2025 enum machine_mode new_mode
2026 = mode_for_extraction (EP_extv, 1);
2027 if (new_mode != MAX_MACHINE_MODE)
2028 wanted_mode = new_mode;
2031 /* If we have a narrower mode, we can do something. */
2032 if (wanted_mode != VOIDmode
2033 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2035 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2036 rtx old_pos = XEXP (x, 2);
2039 /* If the bytes and bits are counted differently, we
2040 must adjust the offset. */
2041 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2042 offset = (GET_MODE_SIZE (is_mode)
2043 - GET_MODE_SIZE (wanted_mode) - offset);
2045 pos %= GET_MODE_BITSIZE (wanted_mode);
2047 newmem = adjust_address_nv (tem, wanted_mode, offset);
2049 /* Make the change and see if the insn remains valid. */
2050 INSN_CODE (insn) = -1;
2051 XEXP (x, 0) = newmem;
2052 XEXP (x, 2) = GEN_INT (pos);
2054 if (recog_memoized (insn) >= 0)
2057 /* Otherwise, restore old position. XEXP (x, 0) will be
2059 XEXP (x, 2) = old_pos;
2063 /* If we get here, the bitfield extract insn can't accept a memory
2064 reference. Copy the input into a register. */
2066 tem1 = gen_reg_rtx (GET_MODE (tem));
2067 emit_insn_before (gen_move_insn (tem1, tem), insn);
2074 if (SUBREG_REG (x) == var)
2076 /* If this is a special SUBREG made because VAR was promoted
2077 from a wider mode, replace it with VAR and call ourself
2078 recursively, this time saying that the object previously
2079 had its current mode (by virtue of the SUBREG). */
2081 if (SUBREG_PROMOTED_VAR_P (x))
2084 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2089 /* If this SUBREG makes VAR wider, it has become a paradoxical
2090 SUBREG with VAR in memory, but these aren't allowed at this
2091 stage of the compilation. So load VAR into a pseudo and take
2092 a SUBREG of that pseudo. */
2093 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2095 replacement = find_fixup_replacement (replacements, var);
2096 if (replacement->new == 0)
2097 replacement->new = gen_reg_rtx (promoted_mode);
2098 SUBREG_REG (x) = replacement->new;
2102 /* See if we have already found a replacement for this SUBREG.
2103 If so, use it. Otherwise, make a MEM and see if the insn
2104 is recognized. If not, or if we should force MEM into a register,
2105 make a pseudo for this SUBREG. */
2106 replacement = find_fixup_replacement (replacements, x);
2107 if (replacement->new)
2109 enum machine_mode mode = GET_MODE (x);
2110 *loc = replacement->new;
2112 /* Careful! We may have just replaced a SUBREG by a MEM, which
2113 means that the insn may have become invalid again. We can't
2114 in this case make a new replacement since we already have one
2115 and we must deal with MATCH_DUPs. */
2116 if (GET_CODE (replacement->new) == MEM)
2118 INSN_CODE (insn) = -1;
2119 if (recog_memoized (insn) >= 0)
2122 fixup_var_refs_1 (replacement->new, mode, &PATTERN (insn),
2123 insn, replacements, no_share);
2129 replacement->new = *loc = fixup_memory_subreg (x, insn,
2132 INSN_CODE (insn) = -1;
2133 if (! flag_force_mem && recog_memoized (insn) >= 0)
2136 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2142 /* First do special simplification of bit-field references. */
2143 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2144 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2145 optimize_bit_field (x, insn, 0);
2146 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2147 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2148 optimize_bit_field (x, insn, 0);
2150 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2151 into a register and then store it back out. */
2152 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2153 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2154 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2155 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2156 > GET_MODE_SIZE (GET_MODE (var))))
2158 replacement = find_fixup_replacement (replacements, var);
2159 if (replacement->new == 0)
2160 replacement->new = gen_reg_rtx (GET_MODE (var));
2162 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2163 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2166 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2167 insn into a pseudo and store the low part of the pseudo into VAR. */
2168 if (GET_CODE (SET_DEST (x)) == SUBREG
2169 && SUBREG_REG (SET_DEST (x)) == var
2170 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2171 > GET_MODE_SIZE (GET_MODE (var))))
2173 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2174 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2181 rtx dest = SET_DEST (x);
2182 rtx src = SET_SRC (x);
2183 rtx outerdest = dest;
2185 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2186 || GET_CODE (dest) == SIGN_EXTRACT
2187 || GET_CODE (dest) == ZERO_EXTRACT)
2188 dest = XEXP (dest, 0);
2190 if (GET_CODE (src) == SUBREG)
2191 src = SUBREG_REG (src);
2193 /* If VAR does not appear at the top level of the SET
2194 just scan the lower levels of the tree. */
2196 if (src != var && dest != var)
2199 /* We will need to rerecognize this insn. */
2200 INSN_CODE (insn) = -1;
2202 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2203 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2205 /* Since this case will return, ensure we fixup all the
2207 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2208 insn, replacements, no_share);
2209 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2210 insn, replacements, no_share);
2211 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2212 insn, replacements, no_share);
2214 tem = XEXP (outerdest, 0);
2216 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2217 that may appear inside a ZERO_EXTRACT.
2218 This was legitimate when the MEM was a REG. */
2219 if (GET_CODE (tem) == SUBREG
2220 && SUBREG_REG (tem) == var)
2221 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2223 tem = fixup_stack_1 (tem, insn);
2225 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2226 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2227 && ! mode_dependent_address_p (XEXP (tem, 0))
2228 && ! MEM_VOLATILE_P (tem))
2230 enum machine_mode wanted_mode;
2231 enum machine_mode is_mode = GET_MODE (tem);
2232 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2234 wanted_mode = mode_for_extraction (EP_insv, 0);
2236 /* If we have a narrower mode, we can do something. */
2237 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2239 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2240 rtx old_pos = XEXP (outerdest, 2);
2243 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2244 offset = (GET_MODE_SIZE (is_mode)
2245 - GET_MODE_SIZE (wanted_mode) - offset);
2247 pos %= GET_MODE_BITSIZE (wanted_mode);
2249 newmem = adjust_address_nv (tem, wanted_mode, offset);
2251 /* Make the change and see if the insn remains valid. */
2252 INSN_CODE (insn) = -1;
2253 XEXP (outerdest, 0) = newmem;
2254 XEXP (outerdest, 2) = GEN_INT (pos);
2256 if (recog_memoized (insn) >= 0)
2259 /* Otherwise, restore old position. XEXP (x, 0) will be
2261 XEXP (outerdest, 2) = old_pos;
2265 /* If we get here, the bit-field store doesn't allow memory
2266 or isn't located at a constant position. Load the value into
2267 a register, do the store, and put it back into memory. */
2269 tem1 = gen_reg_rtx (GET_MODE (tem));
2270 emit_insn_before (gen_move_insn (tem1, tem), insn);
2271 emit_insn_after (gen_move_insn (tem, tem1), insn);
2272 XEXP (outerdest, 0) = tem1;
2276 /* STRICT_LOW_PART is a no-op on memory references
2277 and it can cause combinations to be unrecognizable,
2280 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2281 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2283 /* A valid insn to copy VAR into or out of a register
2284 must be left alone, to avoid an infinite loop here.
2285 If the reference to VAR is by a subreg, fix that up,
2286 since SUBREG is not valid for a memref.
2287 Also fix up the address of the stack slot.
2289 Note that we must not try to recognize the insn until
2290 after we know that we have valid addresses and no
2291 (subreg (mem ...) ...) constructs, since these interfere
2292 with determining the validity of the insn. */
2294 if ((SET_SRC (x) == var
2295 || (GET_CODE (SET_SRC (x)) == SUBREG
2296 && SUBREG_REG (SET_SRC (x)) == var))
2297 && (GET_CODE (SET_DEST (x)) == REG
2298 || (GET_CODE (SET_DEST (x)) == SUBREG
2299 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2300 && GET_MODE (var) == promoted_mode
2301 && x == single_set (insn))
2305 if (GET_CODE (SET_SRC (x)) == SUBREG
2306 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2307 > GET_MODE_SIZE (GET_MODE (var))))
2309 /* This (subreg VAR) is now a paradoxical subreg. We need
2310 to replace VAR instead of the subreg. */
2311 replacement = find_fixup_replacement (replacements, var);
2312 if (replacement->new == NULL_RTX)
2313 replacement->new = gen_reg_rtx (GET_MODE (var));
2314 SUBREG_REG (SET_SRC (x)) = replacement->new;
2318 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2319 if (replacement->new)
2320 SET_SRC (x) = replacement->new;
2321 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2322 SET_SRC (x) = replacement->new
2323 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2326 SET_SRC (x) = replacement->new
2327 = fixup_stack_1 (SET_SRC (x), insn);
2330 if (recog_memoized (insn) >= 0)
2333 /* INSN is not valid, but we know that we want to
2334 copy SET_SRC (x) to SET_DEST (x) in some way. So
2335 we generate the move and see whether it requires more
2336 than one insn. If it does, we emit those insns and
2337 delete INSN. Otherwise, we can just replace the pattern
2338 of INSN; we have already verified above that INSN has
2339 no other function that to do X. */
2341 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2342 if (NEXT_INSN (pat) != NULL_RTX)
2344 last = emit_insn_before (pat, insn);
2346 /* INSN might have REG_RETVAL or other important notes, so
2347 we need to store the pattern of the last insn in the
2348 sequence into INSN similarly to the normal case. LAST
2349 should not have REG_NOTES, but we allow them if INSN has
2351 if (REG_NOTES (last) && REG_NOTES (insn))
2353 if (REG_NOTES (last))
2354 REG_NOTES (insn) = REG_NOTES (last);
2355 PATTERN (insn) = PATTERN (last);
2360 PATTERN (insn) = PATTERN (pat);
2365 if ((SET_DEST (x) == var
2366 || (GET_CODE (SET_DEST (x)) == SUBREG
2367 && SUBREG_REG (SET_DEST (x)) == var))
2368 && (GET_CODE (SET_SRC (x)) == REG
2369 || (GET_CODE (SET_SRC (x)) == SUBREG
2370 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2371 && GET_MODE (var) == promoted_mode
2372 && x == single_set (insn))
2376 if (GET_CODE (SET_DEST (x)) == SUBREG)
2377 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2380 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2382 if (recog_memoized (insn) >= 0)
2385 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2386 if (NEXT_INSN (pat) != NULL_RTX)
2388 last = emit_insn_before (pat, insn);
2390 /* INSN might have REG_RETVAL or other important notes, so
2391 we need to store the pattern of the last insn in the
2392 sequence into INSN similarly to the normal case. LAST
2393 should not have REG_NOTES, but we allow them if INSN has
2395 if (REG_NOTES (last) && REG_NOTES (insn))
2397 if (REG_NOTES (last))
2398 REG_NOTES (insn) = REG_NOTES (last);
2399 PATTERN (insn) = PATTERN (last);
2404 PATTERN (insn) = PATTERN (pat);
2409 /* Otherwise, storing into VAR must be handled specially
2410 by storing into a temporary and copying that into VAR
2411 with a new insn after this one. Note that this case
2412 will be used when storing into a promoted scalar since
2413 the insn will now have different modes on the input
2414 and output and hence will be invalid (except for the case
2415 of setting it to a constant, which does not need any
2416 change if it is valid). We generate extra code in that case,
2417 but combine.c will eliminate it. */
2422 rtx fixeddest = SET_DEST (x);
2423 enum machine_mode temp_mode;
2425 /* STRICT_LOW_PART can be discarded, around a MEM. */
2426 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2427 fixeddest = XEXP (fixeddest, 0);
2428 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2429 if (GET_CODE (fixeddest) == SUBREG)
2431 fixeddest = fixup_memory_subreg (fixeddest, insn,
2433 temp_mode = GET_MODE (fixeddest);
2437 fixeddest = fixup_stack_1 (fixeddest, insn);
2438 temp_mode = promoted_mode;
2441 temp = gen_reg_rtx (temp_mode);
2443 emit_insn_after (gen_move_insn (fixeddest,
2444 gen_lowpart (GET_MODE (fixeddest),
2448 SET_DEST (x) = temp;
2456 /* Nothing special about this RTX; fix its operands. */
2458 fmt = GET_RTX_FORMAT (code);
2459 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2462 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2464 else if (fmt[i] == 'E')
2467 for (j = 0; j < XVECLEN (x, i); j++)
2468 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2469 insn, replacements, no_share);
2474 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2475 The REG was placed on the stack, so X now has the form (SUBREG:m1
2478 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2479 must be emitted to compute NEWADDR, put them before INSN.
2481 UNCRITICAL nonzero means accept paradoxical subregs.
2482 This is used for subregs found inside REG_NOTES. */
2485 fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode, int uncritical)
2488 rtx mem = SUBREG_REG (x);
2489 rtx addr = XEXP (mem, 0);
2490 enum machine_mode mode = GET_MODE (x);
2493 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2494 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2497 offset = SUBREG_BYTE (x);
2498 if (BYTES_BIG_ENDIAN)
2499 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2500 the offset so that it points to the right location within the
2502 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2504 if (!flag_force_addr
2505 && memory_address_p (mode, plus_constant (addr, offset)))
2506 /* Shortcut if no insns need be emitted. */
2507 return adjust_address (mem, mode, offset);
2510 result = adjust_address (mem, mode, offset);
2514 emit_insn_before (seq, insn);
2518 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2519 Replace subexpressions of X in place.
2520 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2521 Otherwise return X, with its contents possibly altered.
2523 INSN, PROMOTED_MODE and UNCRITICAL are as for
2524 fixup_memory_subreg. */
2527 walk_fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode,
2537 code = GET_CODE (x);
2539 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2540 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2542 /* Nothing special about this RTX; fix its operands. */
2544 fmt = GET_RTX_FORMAT (code);
2545 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2548 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2549 promoted_mode, uncritical);
2550 else if (fmt[i] == 'E')
2553 for (j = 0; j < XVECLEN (x, i); j++)
2555 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2556 promoted_mode, uncritical);
2562 /* For each memory ref within X, if it refers to a stack slot
2563 with an out of range displacement, put the address in a temp register
2564 (emitting new insns before INSN to load these registers)
2565 and alter the memory ref to use that register.
2566 Replace each such MEM rtx with a copy, to avoid clobberage. */
2569 fixup_stack_1 (rtx x, rtx insn)
2572 RTX_CODE code = GET_CODE (x);
2577 rtx ad = XEXP (x, 0);
2578 /* If we have address of a stack slot but it's not valid
2579 (displacement is too large), compute the sum in a register. */
2580 if (GET_CODE (ad) == PLUS
2581 && GET_CODE (XEXP (ad, 0)) == REG
2582 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2583 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2584 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2585 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2586 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2588 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2589 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2590 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2591 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2594 if (memory_address_p (GET_MODE (x), ad))
2598 temp = copy_to_reg (ad);
2601 emit_insn_before (seq, insn);
2602 return replace_equiv_address (x, temp);
2607 fmt = GET_RTX_FORMAT (code);
2608 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2611 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2612 else if (fmt[i] == 'E')
2615 for (j = 0; j < XVECLEN (x, i); j++)
2616 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2622 /* Optimization: a bit-field instruction whose field
2623 happens to be a byte or halfword in memory
2624 can be changed to a move instruction.
2626 We call here when INSN is an insn to examine or store into a bit-field.
2627 BODY is the SET-rtx to be altered.
2629 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2630 (Currently this is called only from function.c, and EQUIV_MEM
2634 optimize_bit_field (rtx body, rtx insn, rtx *equiv_mem)
2639 enum machine_mode mode;
2641 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2642 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2643 bitfield = SET_DEST (body), destflag = 1;
2645 bitfield = SET_SRC (body), destflag = 0;
2647 /* First check that the field being stored has constant size and position
2648 and is in fact a byte or halfword suitably aligned. */
2650 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2651 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2652 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2654 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2658 /* Now check that the containing word is memory, not a register,
2659 and that it is safe to change the machine mode. */
2661 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2662 memref = XEXP (bitfield, 0);
2663 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2665 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2666 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2667 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2668 memref = SUBREG_REG (XEXP (bitfield, 0));
2669 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2671 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2672 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2675 && ! mode_dependent_address_p (XEXP (memref, 0))
2676 && ! MEM_VOLATILE_P (memref))
2678 /* Now adjust the address, first for any subreg'ing
2679 that we are now getting rid of,
2680 and then for which byte of the word is wanted. */
2682 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2685 /* Adjust OFFSET to count bits from low-address byte. */
2686 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2687 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2688 - offset - INTVAL (XEXP (bitfield, 1)));
2690 /* Adjust OFFSET to count bytes from low-address byte. */
2691 offset /= BITS_PER_UNIT;
2692 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2694 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2695 / UNITS_PER_WORD) * UNITS_PER_WORD;
2696 if (BYTES_BIG_ENDIAN)
2697 offset -= (MIN (UNITS_PER_WORD,
2698 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2699 - MIN (UNITS_PER_WORD,
2700 GET_MODE_SIZE (GET_MODE (memref))));
2704 memref = adjust_address (memref, mode, offset);
2705 insns = get_insns ();
2707 emit_insn_before (insns, insn);
2709 /* Store this memory reference where
2710 we found the bit field reference. */
2714 validate_change (insn, &SET_DEST (body), memref, 1);
2715 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2717 rtx src = SET_SRC (body);
2718 while (GET_CODE (src) == SUBREG
2719 && SUBREG_BYTE (src) == 0)
2720 src = SUBREG_REG (src);
2721 if (GET_MODE (src) != GET_MODE (memref))
2722 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2723 validate_change (insn, &SET_SRC (body), src, 1);
2725 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2726 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2727 /* This shouldn't happen because anything that didn't have
2728 one of these modes should have got converted explicitly
2729 and then referenced through a subreg.
2730 This is so because the original bit-field was
2731 handled by agg_mode and so its tree structure had
2732 the same mode that memref now has. */
2737 rtx dest = SET_DEST (body);
2739 while (GET_CODE (dest) == SUBREG
2740 && SUBREG_BYTE (dest) == 0
2741 && (GET_MODE_CLASS (GET_MODE (dest))
2742 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2743 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2745 dest = SUBREG_REG (dest);
2747 validate_change (insn, &SET_DEST (body), dest, 1);
2749 if (GET_MODE (dest) == GET_MODE (memref))
2750 validate_change (insn, &SET_SRC (body), memref, 1);
2753 /* Convert the mem ref to the destination mode. */
2754 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2757 convert_move (newreg, memref,
2758 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2762 validate_change (insn, &SET_SRC (body), newreg, 1);
2766 /* See if we can convert this extraction or insertion into
2767 a simple move insn. We might not be able to do so if this
2768 was, for example, part of a PARALLEL.
2770 If we succeed, write out any needed conversions. If we fail,
2771 it is hard to guess why we failed, so don't do anything
2772 special; just let the optimization be suppressed. */
2774 if (apply_change_group () && seq)
2775 emit_insn_before (seq, insn);
2780 /* These routines are responsible for converting virtual register references
2781 to the actual hard register references once RTL generation is complete.
2783 The following four variables are used for communication between the
2784 routines. They contain the offsets of the virtual registers from their
2785 respective hard registers. */
2787 static int in_arg_offset;
2788 static int var_offset;
2789 static int dynamic_offset;
2790 static int out_arg_offset;
2791 static int cfa_offset;
2793 /* In most machines, the stack pointer register is equivalent to the bottom
2796 #ifndef STACK_POINTER_OFFSET
2797 #define STACK_POINTER_OFFSET 0
2800 /* If not defined, pick an appropriate default for the offset of dynamically
2801 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2802 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2804 #ifndef STACK_DYNAMIC_OFFSET
2806 /* The bottom of the stack points to the actual arguments. If
2807 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2808 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2809 stack space for register parameters is not pushed by the caller, but
2810 rather part of the fixed stack areas and hence not included in
2811 `current_function_outgoing_args_size'. Nevertheless, we must allow
2812 for it when allocating stack dynamic objects. */
2814 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2815 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2816 ((ACCUMULATE_OUTGOING_ARGS \
2817 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2818 + (STACK_POINTER_OFFSET)) \
2821 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2822 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2823 + (STACK_POINTER_OFFSET))
2827 /* On most machines, the CFA coincides with the first incoming parm. */
2829 #ifndef ARG_POINTER_CFA_OFFSET
2830 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2833 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2834 had its address taken. DECL is the decl or SAVE_EXPR for the
2835 object stored in the register, for later use if we do need to force
2836 REG into the stack. REG is overwritten by the MEM like in
2837 put_reg_into_stack. RESCAN is true if previously emitted
2838 instructions must be rescanned and modified now that the REG has
2839 been transformed. */
2842 gen_mem_addressof (rtx reg, tree decl, int rescan)
2844 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2847 /* Calculate this before we start messing with decl's RTL. */
2848 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2850 /* If the original REG was a user-variable, then so is the REG whose
2851 address is being taken. Likewise for unchanging. */
2852 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2853 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2855 PUT_CODE (reg, MEM);
2856 MEM_ATTRS (reg) = 0;
2861 tree type = TREE_TYPE (decl);
2862 enum machine_mode decl_mode
2863 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2864 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2865 : DECL_RTL_IF_SET (decl));
2867 PUT_MODE (reg, decl_mode);
2869 /* Clear DECL_RTL momentarily so functions below will work
2870 properly, then set it again. */
2871 if (DECL_P (decl) && decl_rtl == reg)
2872 SET_DECL_RTL (decl, 0);
2874 set_mem_attributes (reg, decl, 1);
2875 set_mem_alias_set (reg, set);
2877 if (DECL_P (decl) && decl_rtl == reg)
2878 SET_DECL_RTL (decl, reg);
2881 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0)))
2882 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2886 /* This can only happen during reload. Clear the same flag bits as
2888 MEM_VOLATILE_P (reg) = 0;
2889 RTX_UNCHANGING_P (reg) = 0;
2890 MEM_IN_STRUCT_P (reg) = 0;
2891 MEM_SCALAR_P (reg) = 0;
2892 MEM_ATTRS (reg) = 0;
2894 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2900 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2903 flush_addressof (tree decl)
2905 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2906 && DECL_RTL (decl) != 0
2907 && GET_CODE (DECL_RTL (decl)) == MEM
2908 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2909 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2910 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2913 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2916 put_addressof_into_stack (rtx r, htab_t ht)
2919 bool volatile_p, used_p;
2921 rtx reg = XEXP (r, 0);
2923 if (GET_CODE (reg) != REG)
2926 decl = ADDRESSOF_DECL (r);
2929 type = TREE_TYPE (decl);
2930 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2931 && TREE_THIS_VOLATILE (decl));
2932 used_p = (TREE_USED (decl)
2933 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2942 put_reg_into_stack (0, reg, type, GET_MODE (reg), ADDRESSOF_REGNO (r),
2943 volatile_p, used_p, false, ht);
2946 /* List of replacements made below in purge_addressof_1 when creating
2947 bitfield insertions. */
2948 static rtx purge_bitfield_addressof_replacements;
2950 /* List of replacements made below in purge_addressof_1 for patterns
2951 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2952 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2953 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2954 enough in complex cases, e.g. when some field values can be
2955 extracted by usage MEM with narrower mode. */
2956 static rtx purge_addressof_replacements;
2958 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2959 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2960 the stack. If the function returns FALSE then the replacement could not
2961 be made. If MAY_POSTPONE is true and we would not put the addressof
2962 to stack, postpone processing of the insn. */
2965 purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
2973 bool libcall = false;
2975 /* Re-start here to avoid recursion in common cases. */
2982 /* Is this a libcall? */
2984 libcall = REG_NOTE_KIND (*loc) == REG_RETVAL;
2986 code = GET_CODE (x);
2988 /* If we don't return in any of the cases below, we will recurse inside
2989 the RTX, which will normally result in any ADDRESSOF being forced into
2993 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1,
2995 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0,
2999 else if (code == ADDRESSOF)
3003 if (GET_CODE (XEXP (x, 0)) != MEM)
3004 put_addressof_into_stack (x, ht);
3006 /* We must create a copy of the rtx because it was created by
3007 overwriting a REG rtx which is always shared. */
3008 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3009 if (validate_change (insn, loc, sub, 0)
3010 || validate_replace_rtx (x, sub, insn))
3015 /* If SUB is a hard or virtual register, try it as a pseudo-register.
3016 Otherwise, perhaps SUB is an expression, so generate code to compute
3018 if (GET_CODE (sub) == REG && REGNO (sub) <= LAST_VIRTUAL_REGISTER)
3019 sub = copy_to_reg (sub);
3021 sub = force_operand (sub, NULL_RTX);
3023 if (! validate_change (insn, loc, sub, 0)
3024 && ! validate_replace_rtx (x, sub, insn))
3027 insns = get_insns ();
3029 emit_insn_before (insns, insn);
3033 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3035 rtx sub = XEXP (XEXP (x, 0), 0);
3037 if (GET_CODE (sub) == MEM)
3038 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3039 else if (GET_CODE (sub) == REG
3040 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3042 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3044 int size_x, size_sub;
3048 /* Postpone for now, so that we do not emit bitfield arithmetics
3049 unless there is some benefit from it. */
3050 if (!postponed_insns || XEXP (postponed_insns, 0) != insn)
3051 postponed_insns = alloc_INSN_LIST (insn, postponed_insns);
3057 /* When processing REG_NOTES look at the list of
3058 replacements done on the insn to find the register that X
3062 for (tem = purge_bitfield_addressof_replacements;
3064 tem = XEXP (XEXP (tem, 1), 1))
3065 if (rtx_equal_p (x, XEXP (tem, 0)))
3067 *loc = XEXP (XEXP (tem, 1), 0);
3071 /* See comment for purge_addressof_replacements. */
3072 for (tem = purge_addressof_replacements;
3074 tem = XEXP (XEXP (tem, 1), 1))
3075 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3077 rtx z = XEXP (XEXP (tem, 1), 0);
3079 if (GET_MODE (x) == GET_MODE (z)
3080 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3081 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3084 /* It can happen that the note may speak of things
3085 in a wider (or just different) mode than the
3086 code did. This is especially true of
3089 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3092 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3093 && (GET_MODE_SIZE (GET_MODE (x))
3094 > GET_MODE_SIZE (GET_MODE (z))))
3096 /* This can occur as a result in invalid
3097 pointer casts, e.g. float f; ...
3098 *(long long int *)&f.
3099 ??? We could emit a warning here, but
3100 without a line number that wouldn't be
3102 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3105 z = gen_lowpart (GET_MODE (x), z);
3111 /* When we are processing the REG_NOTES of the last instruction
3112 of a libcall, there will be typically no replacements
3113 for that insn; the replacements happened before, piecemeal
3114 fashion. OTOH we are not interested in the details of
3115 this for the REG_EQUAL note, we want to know the big picture,
3116 which can be succinctly described with a simple SUBREG.
3117 Note that removing the REG_EQUAL note is not an option
3118 on the last insn of a libcall, so we must do a replacement. */
3120 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
3122 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
3123 [0 S8 A32]), which can be expressed with a simple
3125 if ((GET_MODE_SIZE (GET_MODE (x))
3126 <= GET_MODE_SIZE (GET_MODE (sub)))
3127 /* Again, invalid pointer casts (as in
3128 compile/990203-1.c) can require paradoxical
3130 || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3131 && (GET_MODE_SIZE (GET_MODE (x))
3132 > GET_MODE_SIZE (GET_MODE (sub)))
3135 *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
3138 /* ??? Are there other cases we should handle? */
3140 /* Sometimes we may not be able to find the replacement. For
3141 example when the original insn was a MEM in a wider mode,
3142 and the note is part of a sign extension of a narrowed
3143 version of that MEM. Gcc testcase compile/990829-1.c can
3144 generate an example of this situation. Rather than complain
3145 we return false, which will prompt our caller to remove the
3150 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3151 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3153 /* Do not frob unchanging MEMs. If a later reference forces the
3154 pseudo to the stack, we can wind up with multiple writes to
3155 an unchanging memory, which is invalid. */
3156 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3159 /* Don't even consider working with paradoxical subregs,
3160 or the moral equivalent seen here. */
3161 else if (size_x <= size_sub
3162 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3164 /* Do a bitfield insertion to mirror what would happen
3171 rtx p = PREV_INSN (insn);
3174 val = gen_reg_rtx (GET_MODE (x));
3175 if (! validate_change (insn, loc, val, 0))
3177 /* Discard the current sequence and put the
3178 ADDRESSOF on stack. */
3184 emit_insn_before (seq, insn);
3185 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3189 store_bit_field (sub, size_x, 0, GET_MODE (x),
3190 val, GET_MODE_SIZE (GET_MODE (sub)));
3192 /* Make sure to unshare any shared rtl that store_bit_field
3193 might have created. */
3194 unshare_all_rtl_again (get_insns ());
3198 p = emit_insn_after (seq, insn);
3199 if (NEXT_INSN (insn))
3200 compute_insns_for_mem (NEXT_INSN (insn),
3201 p ? NEXT_INSN (p) : NULL_RTX,
3206 rtx p = PREV_INSN (insn);
3209 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3210 GET_MODE (x), GET_MODE (x),
3211 GET_MODE_SIZE (GET_MODE (sub)));
3213 if (! validate_change (insn, loc, val, 0))
3215 /* Discard the current sequence and put the
3216 ADDRESSOF on stack. */
3223 emit_insn_before (seq, insn);
3224 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3228 /* Remember the replacement so that the same one can be done
3229 on the REG_NOTES. */
3230 purge_bitfield_addressof_replacements
3231 = gen_rtx_EXPR_LIST (VOIDmode, x,
3234 purge_bitfield_addressof_replacements));
3236 /* We replaced with a reg -- all done. */
3241 else if (validate_change (insn, loc, sub, 0))
3243 /* Remember the replacement so that the same one can be done
3244 on the REG_NOTES. */
3245 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3249 for (tem = purge_addressof_replacements;
3251 tem = XEXP (XEXP (tem, 1), 1))
3252 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3254 XEXP (XEXP (tem, 1), 0) = sub;
3257 purge_addressof_replacements
3258 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3259 gen_rtx_EXPR_LIST (VOIDmode, sub,
3260 purge_addressof_replacements));
3268 /* Scan all subexpressions. */
3269 fmt = GET_RTX_FORMAT (code);
3270 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3273 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0,
3275 else if (*fmt == 'E')
3276 for (j = 0; j < XVECLEN (x, i); j++)
3277 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0,
3284 /* Return a hash value for K, a REG. */
3287 insns_for_mem_hash (const void *k)
3289 /* Use the address of the key for the hash value. */
3290 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3291 return htab_hash_pointer (m->key);
3294 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3297 insns_for_mem_comp (const void *k1, const void *k2)
3299 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3300 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3301 return m1->key == m2->key;
3304 struct insns_for_mem_walk_info
3306 /* The hash table that we are using to record which INSNs use which
3310 /* The INSN we are currently processing. */
3313 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3314 to find the insns that use the REGs in the ADDRESSOFs. */
3318 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3319 that might be used in an ADDRESSOF expression, record this INSN in
3320 the hash table given by DATA (which is really a pointer to an
3321 insns_for_mem_walk_info structure). */
3324 insns_for_mem_walk (rtx *r, void *data)
3326 struct insns_for_mem_walk_info *ifmwi
3327 = (struct insns_for_mem_walk_info *) data;
3328 struct insns_for_mem_entry tmp;
3329 tmp.insns = NULL_RTX;
3331 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3332 && GET_CODE (XEXP (*r, 0)) == REG)
3335 tmp.key = XEXP (*r, 0);
3336 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3339 *e = ggc_alloc (sizeof (tmp));
3340 memcpy (*e, &tmp, sizeof (tmp));
3343 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3345 struct insns_for_mem_entry *ifme;
3347 ifme = htab_find (ifmwi->ht, &tmp);
3349 /* If we have not already recorded this INSN, do so now. Since
3350 we process the INSNs in order, we know that if we have
3351 recorded it it must be at the front of the list. */
3352 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3353 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3360 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3361 which REGs in HT. */
3364 compute_insns_for_mem (rtx insns, rtx last_insn, htab_t ht)
3367 struct insns_for_mem_walk_info ifmwi;
3370 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3371 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3375 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3379 /* Helper function for purge_addressof called through for_each_rtx.
3380 Returns true iff the rtl is an ADDRESSOF. */
3383 is_addressof (rtx *rtl, void *data ATTRIBUTE_UNUSED)
3385 return GET_CODE (*rtl) == ADDRESSOF;
3388 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3389 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3393 purge_addressof (rtx insns)
3398 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3399 requires a fixup pass over the instruction stream to correct
3400 INSNs that depended on the REG being a REG, and not a MEM. But,
3401 these fixup passes are slow. Furthermore, most MEMs are not
3402 mentioned in very many instructions. So, we speed up the process
3403 by pre-calculating which REGs occur in which INSNs; that allows
3404 us to perform the fixup passes much more quickly. */
3405 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3406 compute_insns_for_mem (insns, NULL_RTX, ht);
3408 postponed_insns = NULL;
3410 for (insn = insns; insn; insn = NEXT_INSN (insn))
3413 if (! purge_addressof_1 (&PATTERN (insn), insn,
3414 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht))
3415 /* If we could not replace the ADDRESSOFs in the insn,
3416 something is wrong. */
3419 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht))
3421 /* If we could not replace the ADDRESSOFs in the insn's notes,
3422 we can just remove the offending notes instead. */
3425 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3427 /* If we find a REG_RETVAL note then the insn is a libcall.
3428 Such insns must have REG_EQUAL notes as well, in order
3429 for later passes of the compiler to work. So it is not
3430 safe to delete the notes here, and instead we abort. */
3431 if (REG_NOTE_KIND (note) == REG_RETVAL)
3433 if (for_each_rtx (¬e, is_addressof, NULL))
3434 remove_note (insn, note);
3439 /* Process the postponed insns. */
3440 while (postponed_insns)
3442 insn = XEXP (postponed_insns, 0);
3443 tmp = postponed_insns;
3444 postponed_insns = XEXP (postponed_insns, 1);
3445 free_INSN_LIST_node (tmp);
3447 if (! purge_addressof_1 (&PATTERN (insn), insn,
3448 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht))
3453 purge_bitfield_addressof_replacements = 0;
3454 purge_addressof_replacements = 0;
3456 /* REGs are shared. purge_addressof will destructively replace a REG
3457 with a MEM, which creates shared MEMs.
3459 Unfortunately, the children of put_reg_into_stack assume that MEMs
3460 referring to the same stack slot are shared (fixup_var_refs and
3461 the associated hash table code).
3463 So, we have to do another unsharing pass after we have flushed any
3464 REGs that had their address taken into the stack.
3466 It may be worth tracking whether or not we converted any REGs into
3467 MEMs to avoid this overhead when it is not needed. */
3468 unshare_all_rtl_again (get_insns ());
3471 /* Convert a SET of a hard subreg to a set of the appropriate hard
3472 register. A subroutine of purge_hard_subreg_sets. */
3475 purge_single_hard_subreg_set (rtx pattern)
3477 rtx reg = SET_DEST (pattern);
3478 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3481 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3482 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3484 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3485 GET_MODE (SUBREG_REG (reg)),
3488 reg = SUBREG_REG (reg);
3492 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3494 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3495 SET_DEST (pattern) = reg;
3499 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3500 only such SETs that we expect to see are those left in because
3501 integrate can't handle sets of parts of a return value register.
3503 We don't use alter_subreg because we only want to eliminate subregs
3504 of hard registers. */
3507 purge_hard_subreg_sets (rtx insn)
3509 for (; insn; insn = NEXT_INSN (insn))
3513 rtx pattern = PATTERN (insn);
3514 switch (GET_CODE (pattern))
3517 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3518 purge_single_hard_subreg_set (pattern);
3523 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3525 rtx inner_pattern = XVECEXP (pattern, 0, j);
3526 if (GET_CODE (inner_pattern) == SET
3527 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3528 purge_single_hard_subreg_set (inner_pattern);
3539 /* Pass through the INSNS of function FNDECL and convert virtual register
3540 references to hard register references. */
3543 instantiate_virtual_regs (tree fndecl, rtx insns)
3548 /* Compute the offsets to use for this function. */
3549 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3550 var_offset = STARTING_FRAME_OFFSET;
3551 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3552 out_arg_offset = STACK_POINTER_OFFSET;
3553 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3555 /* Scan all variables and parameters of this function. For each that is
3556 in memory, instantiate all virtual registers if the result is a valid
3557 address. If not, we do it later. That will handle most uses of virtual
3558 regs on many machines. */
3559 instantiate_decls (fndecl, 1);
3561 /* Initialize recognition, indicating that volatile is OK. */
3564 /* Scan through all the insns, instantiating every virtual register still
3566 for (insn = insns; insn; insn = NEXT_INSN (insn))
3567 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3568 || GET_CODE (insn) == CALL_INSN)
3570 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3571 if (INSN_DELETED_P (insn))
3573 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3574 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3575 if (GET_CODE (insn) == CALL_INSN)
3576 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3579 /* Past this point all ASM statements should match. Verify that
3580 to avoid failures later in the compilation process. */
3581 if (asm_noperands (PATTERN (insn)) >= 0
3582 && ! check_asm_operands (PATTERN (insn)))
3583 instantiate_virtual_regs_lossage (insn);
3586 /* Instantiate the stack slots for the parm registers, for later use in
3587 addressof elimination. */
3588 for (i = 0; i < max_parm_reg; ++i)
3589 if (parm_reg_stack_loc[i])
3590 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3592 /* Now instantiate the remaining register equivalences for debugging info.
3593 These will not be valid addresses. */
3594 instantiate_decls (fndecl, 0);
3596 /* Indicate that, from now on, assign_stack_local should use
3597 frame_pointer_rtx. */
3598 virtuals_instantiated = 1;
3601 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3602 all virtual registers in their DECL_RTL's.
3604 If VALID_ONLY, do this only if the resulting address is still valid.
3605 Otherwise, always do it. */
3608 instantiate_decls (tree fndecl, int valid_only)
3612 /* Process all parameters of the function. */
3613 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3615 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3616 HOST_WIDE_INT size_rtl;
3618 instantiate_decl (DECL_RTL (decl), size, valid_only);
3620 /* If the parameter was promoted, then the incoming RTL mode may be
3621 larger than the declared type size. We must use the larger of
3623 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3624 size = MAX (size_rtl, size);
3625 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3628 /* Now process all variables defined in the function or its subblocks. */
3629 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3632 /* Subroutine of instantiate_decls: Process all decls in the given
3633 BLOCK node and all its subblocks. */
3636 instantiate_decls_1 (tree let, int valid_only)
3640 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3641 if (DECL_RTL_SET_P (t))
3642 instantiate_decl (DECL_RTL (t),
3643 int_size_in_bytes (TREE_TYPE (t)),
3646 /* Process all subblocks. */
3647 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3648 instantiate_decls_1 (t, valid_only);
3651 /* Subroutine of the preceding procedures: Given RTL representing a
3652 decl and the size of the object, do any instantiation required.
3654 If VALID_ONLY is nonzero, it means that the RTL should only be
3655 changed if the new address is valid. */
3658 instantiate_decl (rtx x, HOST_WIDE_INT size, int valid_only)
3660 enum machine_mode mode;
3666 /* If this is a CONCAT, recurse for the pieces. */
3667 if (GET_CODE (x) == CONCAT)
3669 instantiate_decl (XEXP (x, 0), size / 2, valid_only);
3670 instantiate_decl (XEXP (x, 1), size / 2, valid_only);
3674 /* If this is not a MEM, no need to do anything. Similarly if the
3675 address is a constant or a register that is not a virtual register. */
3676 if (GET_CODE (x) != MEM)
3680 if (CONSTANT_P (addr)
3681 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3682 || (GET_CODE (addr) == REG
3683 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3684 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3687 /* If we should only do this if the address is valid, copy the address.
3688 We need to do this so we can undo any changes that might make the
3689 address invalid. This copy is unfortunate, but probably can't be
3693 addr = copy_rtx (addr);
3695 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3697 if (valid_only && size >= 0)
3699 unsigned HOST_WIDE_INT decl_size = size;
3701 /* Now verify that the resulting address is valid for every integer or
3702 floating-point mode up to and including SIZE bytes long. We do this
3703 since the object might be accessed in any mode and frame addresses
3706 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3707 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3708 mode = GET_MODE_WIDER_MODE (mode))
3709 if (! memory_address_p (mode, addr))
3712 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3713 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3714 mode = GET_MODE_WIDER_MODE (mode))
3715 if (! memory_address_p (mode, addr))
3719 /* Put back the address now that we have updated it and we either know
3720 it is valid or we don't care whether it is valid. */
3725 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3726 is a virtual register, return the equivalent hard register and set the
3727 offset indirectly through the pointer. Otherwise, return 0. */
3730 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
3733 HOST_WIDE_INT offset;
3735 if (x == virtual_incoming_args_rtx)
3736 new = arg_pointer_rtx, offset = in_arg_offset;
3737 else if (x == virtual_stack_vars_rtx)
3738 new = frame_pointer_rtx, offset = var_offset;
3739 else if (x == virtual_stack_dynamic_rtx)
3740 new = stack_pointer_rtx, offset = dynamic_offset;
3741 else if (x == virtual_outgoing_args_rtx)
3742 new = stack_pointer_rtx, offset = out_arg_offset;
3743 else if (x == virtual_cfa_rtx)
3744 new = arg_pointer_rtx, offset = cfa_offset;
3753 /* Called when instantiate_virtual_regs has failed to update the instruction.
3754 Usually this means that non-matching instruction has been emit, however for
3755 asm statements it may be the problem in the constraints. */
3757 instantiate_virtual_regs_lossage (rtx insn)
3759 if (asm_noperands (PATTERN (insn)) >= 0)
3761 error_for_asm (insn, "impossible constraint in `asm'");
3767 /* Given a pointer to a piece of rtx and an optional pointer to the
3768 containing object, instantiate any virtual registers present in it.
3770 If EXTRA_INSNS, we always do the replacement and generate
3771 any extra insns before OBJECT. If it zero, we do nothing if replacement
3774 Return 1 if we either had nothing to do or if we were able to do the
3775 needed replacement. Return 0 otherwise; we only return zero if
3776 EXTRA_INSNS is zero.
3778 We first try some simple transformations to avoid the creation of extra
3782 instantiate_virtual_regs_1 (rtx *loc, rtx object, int extra_insns)
3787 HOST_WIDE_INT offset = 0;
3793 /* Re-start here to avoid recursion in common cases. */
3800 /* We may have detected and deleted invalid asm statements. */
3801 if (object && INSN_P (object) && INSN_DELETED_P (object))
3804 code = GET_CODE (x);
3806 /* Check for some special cases. */
3824 /* We are allowed to set the virtual registers. This means that
3825 the actual register should receive the source minus the
3826 appropriate offset. This is used, for example, in the handling
3827 of non-local gotos. */
3828 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3830 rtx src = SET_SRC (x);
3832 /* We are setting the register, not using it, so the relevant
3833 offset is the negative of the offset to use were we using
3836 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3838 /* The only valid sources here are PLUS or REG. Just do
3839 the simplest possible thing to handle them. */
3840 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3842 instantiate_virtual_regs_lossage (object);
3847 if (GET_CODE (src) != REG)
3848 temp = force_operand (src, NULL_RTX);
3851 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3855 emit_insn_before (seq, object);
3858 if (! validate_change (object, &SET_SRC (x), temp, 0)
3860 instantiate_virtual_regs_lossage (object);
3865 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3870 /* Handle special case of virtual register plus constant. */
3871 if (CONSTANT_P (XEXP (x, 1)))
3873 rtx old, new_offset;
3875 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3876 if (GET_CODE (XEXP (x, 0)) == PLUS)
3878 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3880 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3882 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3891 #ifdef POINTERS_EXTEND_UNSIGNED
3892 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3893 we can commute the PLUS and SUBREG because pointers into the
3894 frame are well-behaved. */
3895 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3896 && GET_CODE (XEXP (x, 1)) == CONST_INT
3898 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3900 && validate_change (object, loc,
3901 plus_constant (gen_lowpart (ptr_mode,
3904 + INTVAL (XEXP (x, 1))),
3908 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3910 /* We know the second operand is a constant. Unless the
3911 first operand is a REG (which has been already checked),
3912 it needs to be checked. */
3913 if (GET_CODE (XEXP (x, 0)) != REG)
3921 new_offset = plus_constant (XEXP (x, 1), offset);
3923 /* If the new constant is zero, try to replace the sum with just
3925 if (new_offset == const0_rtx
3926 && validate_change (object, loc, new, 0))
3929 /* Next try to replace the register and new offset.
3930 There are two changes to validate here and we can't assume that
3931 in the case of old offset equals new just changing the register
3932 will yield a valid insn. In the interests of a little efficiency,
3933 however, we only call validate change once (we don't queue up the
3934 changes and then call apply_change_group). */
3938 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3939 : (XEXP (x, 0) = new,
3940 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3948 /* Otherwise copy the new constant into a register and replace
3949 constant with that register. */
3950 temp = gen_reg_rtx (Pmode);
3952 if (validate_change (object, &XEXP (x, 1), temp, 0))
3953 emit_insn_before (gen_move_insn (temp, new_offset), object);
3956 /* If that didn't work, replace this expression with a
3957 register containing the sum. */
3960 new = gen_rtx_PLUS (Pmode, new, new_offset);
3963 temp = force_operand (new, NULL_RTX);
3967 emit_insn_before (seq, object);
3968 if (! validate_change (object, loc, temp, 0)
3969 && ! validate_replace_rtx (x, temp, object))
3971 instantiate_virtual_regs_lossage (object);
3980 /* Fall through to generic two-operand expression case. */
3986 case DIV: case UDIV:
3987 case MOD: case UMOD:
3988 case AND: case IOR: case XOR:
3989 case ROTATERT: case ROTATE:
3990 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3992 case GE: case GT: case GEU: case GTU:
3993 case LE: case LT: case LEU: case LTU:
3994 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3995 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
4000 /* Most cases of MEM that convert to valid addresses have already been
4001 handled by our scan of decls. The only special handling we
4002 need here is to make a copy of the rtx to ensure it isn't being
4003 shared if we have to change it to a pseudo.
4005 If the rtx is a simple reference to an address via a virtual register,
4006 it can potentially be shared. In such cases, first try to make it
4007 a valid address, which can also be shared. Otherwise, copy it and
4010 First check for common cases that need no processing. These are
4011 usually due to instantiation already being done on a previous instance
4015 if (CONSTANT_ADDRESS_P (temp)
4016 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4017 || temp == arg_pointer_rtx
4019 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4020 || temp == hard_frame_pointer_rtx
4022 || temp == frame_pointer_rtx)
4025 if (GET_CODE (temp) == PLUS
4026 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4027 && (XEXP (temp, 0) == frame_pointer_rtx
4028 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4029 || XEXP (temp, 0) == hard_frame_pointer_rtx
4031 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4032 || XEXP (temp, 0) == arg_pointer_rtx
4037 if (temp == virtual_stack_vars_rtx
4038 || temp == virtual_incoming_args_rtx
4039 || (GET_CODE (temp) == PLUS
4040 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4041 && (XEXP (temp, 0) == virtual_stack_vars_rtx
4042 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
4044 /* This MEM may be shared. If the substitution can be done without
4045 the need to generate new pseudos, we want to do it in place
4046 so all copies of the shared rtx benefit. The call below will
4047 only make substitutions if the resulting address is still
4050 Note that we cannot pass X as the object in the recursive call
4051 since the insn being processed may not allow all valid
4052 addresses. However, if we were not passed on object, we can
4053 only modify X without copying it if X will have a valid
4056 ??? Also note that this can still lose if OBJECT is an insn that
4057 has less restrictions on an address that some other insn.
4058 In that case, we will modify the shared address. This case
4059 doesn't seem very likely, though. One case where this could
4060 happen is in the case of a USE or CLOBBER reference, but we
4061 take care of that below. */
4063 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4064 object ? object : x, 0))
4067 /* Otherwise make a copy and process that copy. We copy the entire
4068 RTL expression since it might be a PLUS which could also be
4070 *loc = x = copy_rtx (x);
4073 /* Fall through to generic unary operation case. */
4076 case STRICT_LOW_PART:
4078 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4079 case SIGN_EXTEND: case ZERO_EXTEND:
4080 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4081 case FLOAT: case FIX:
4082 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4087 case POPCOUNT: case PARITY:
4088 /* These case either have just one operand or we know that we need not
4089 check the rest of the operands. */
4095 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4096 go ahead and make the invalid one, but do it to a copy. For a REG,
4097 just make the recursive call, since there's no chance of a problem. */
4099 if ((GET_CODE (XEXP (x, 0)) == MEM
4100 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4102 || (GET_CODE (XEXP (x, 0)) == REG
4103 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4106 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4111 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4112 in front of this insn and substitute the temporary. */
4113 if ((new = instantiate_new_reg (x, &offset)) != 0)
4115 temp = plus_constant (new, offset);
4116 if (!validate_change (object, loc, temp, 0))
4122 temp = force_operand (temp, NULL_RTX);
4126 emit_insn_before (seq, object);
4127 if (! validate_change (object, loc, temp, 0)
4128 && ! validate_replace_rtx (x, temp, object))
4129 instantiate_virtual_regs_lossage (object);
4136 if (GET_CODE (XEXP (x, 0)) == REG)
4139 else if (GET_CODE (XEXP (x, 0)) == MEM)
4141 /* If we have a (addressof (mem ..)), do any instantiation inside
4142 since we know we'll be making the inside valid when we finally
4143 remove the ADDRESSOF. */
4144 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4153 /* Scan all subexpressions. */
4154 fmt = GET_RTX_FORMAT (code);
4155 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4158 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4161 else if (*fmt == 'E')
4162 for (j = 0; j < XVECLEN (x, i); j++)
4163 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4170 /* Optimization: assuming this function does not receive nonlocal gotos,
4171 delete the handlers for such, as well as the insns to establish
4172 and disestablish them. */
4175 delete_handlers (void)
4178 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4180 /* Delete the handler by turning off the flag that would
4181 prevent jump_optimize from deleting it.
4182 Also permit deletion of the nonlocal labels themselves
4183 if nothing local refers to them. */
4184 if (GET_CODE (insn) == CODE_LABEL)
4188 LABEL_PRESERVE_P (insn) = 0;
4190 /* Remove it from the nonlocal_label list, to avoid confusing
4192 for (t = nonlocal_labels, last_t = 0; t;
4193 last_t = t, t = TREE_CHAIN (t))
4194 if (DECL_RTL (TREE_VALUE (t)) == insn)
4199 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4201 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4204 if (GET_CODE (insn) == INSN)
4208 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4209 if (reg_mentioned_p (t, PATTERN (insn)))
4215 || (nonlocal_goto_stack_level != 0
4216 && reg_mentioned_p (nonlocal_goto_stack_level,
4218 delete_related_insns (insn);
4223 /* Return the first insn following those generated by `assign_parms'. */
4226 get_first_nonparm_insn (void)
4229 return NEXT_INSN (last_parm_insn);
4230 return get_insns ();
4233 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4234 This means a type for which function calls must pass an address to the
4235 function or get an address back from the function.
4236 EXP may be a type node or an expression (whose type is tested). */
4239 aggregate_value_p (tree exp, tree fntype)
4241 int i, regno, nregs;
4244 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4247 switch (TREE_CODE (fntype))
4250 fntype = get_callee_fndecl (fntype);
4251 fntype = fntype ? TREE_TYPE (fntype) : 0;
4254 fntype = TREE_TYPE (fntype);
4259 case IDENTIFIER_NODE:
4263 /* We don't expect other rtl types here. */
4267 if (TREE_CODE (type) == VOID_TYPE)
4269 if (targetm.calls.return_in_memory (type, fntype))
4271 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4272 and thus can't be returned in registers. */
4273 if (TREE_ADDRESSABLE (type))
4275 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4277 /* Make sure we have suitable call-clobbered regs to return
4278 the value in; if not, we must return it in memory. */
4279 reg = hard_function_value (type, 0, 0);
4281 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4283 if (GET_CODE (reg) != REG)
4286 regno = REGNO (reg);
4287 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4288 for (i = 0; i < nregs; i++)
4289 if (! call_used_regs[regno + i])
4294 /* Assign RTL expressions to the function's parameters.
4295 This may involve copying them into registers and using
4296 those registers as the RTL for them. */
4299 assign_parms (tree fndecl)
4302 CUMULATIVE_ARGS args_so_far;
4303 /* Total space needed so far for args on the stack,
4304 given as a constant and a tree-expression. */
4305 struct args_size stack_args_size;
4306 tree fntype = TREE_TYPE (fndecl);
4307 tree fnargs = DECL_ARGUMENTS (fndecl), orig_fnargs;
4308 /* This is used for the arg pointer when referring to stack args. */
4309 rtx internal_arg_pointer;
4310 /* This is a dummy PARM_DECL that we used for the function result if
4311 the function returns a structure. */
4312 tree function_result_decl = 0;
4313 int varargs_setup = 0;
4314 int reg_parm_stack_space ATTRIBUTE_UNUSED = 0;
4315 rtx conversion_insns = 0;
4317 /* Nonzero if function takes extra anonymous args.
4318 This means the last named arg must be on the stack
4319 right before the anonymous ones. */
4321 = (TYPE_ARG_TYPES (fntype) != 0
4322 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4323 != void_type_node));
4325 current_function_stdarg = stdarg;
4327 /* If the reg that the virtual arg pointer will be translated into is
4328 not a fixed reg or is the stack pointer, make a copy of the virtual
4329 arg pointer, and address parms via the copy. The frame pointer is
4330 considered fixed even though it is not marked as such.
4332 The second time through, simply use ap to avoid generating rtx. */
4334 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4335 || ! (fixed_regs[ARG_POINTER_REGNUM]
4336 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4337 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4339 internal_arg_pointer = virtual_incoming_args_rtx;
4340 current_function_internal_arg_pointer = internal_arg_pointer;
4342 stack_args_size.constant = 0;
4343 stack_args_size.var = 0;
4345 /* If struct value address is treated as the first argument, make it so. */
4346 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
4347 && ! current_function_returns_pcc_struct
4348 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
4350 tree type = build_pointer_type (TREE_TYPE (fntype));
4352 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4354 DECL_ARG_TYPE (function_result_decl) = type;
4355 TREE_CHAIN (function_result_decl) = fnargs;
4356 fnargs = function_result_decl;
4359 orig_fnargs = fnargs;
4361 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4362 parm_reg_stack_loc = ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4364 /* If the target wants to split complex arguments into scalars, do so. */
4365 if (targetm.calls.split_complex_arg)
4366 fnargs = split_complex_args (fnargs);
4368 #ifdef REG_PARM_STACK_SPACE
4369 #ifdef MAYBE_REG_PARM_STACK_SPACE
4370 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4372 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4376 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4377 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4379 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl, -1);
4382 /* We haven't yet found an argument that we must push and pretend the
4384 current_function_pretend_args_size = 0;
4386 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4390 enum machine_mode promoted_mode, passed_mode;
4391 enum machine_mode nominal_mode, promoted_nominal_mode;
4393 struct locate_and_pad_arg_data locate;
4394 int passed_pointer = 0;
4395 int did_conversion = 0;
4396 tree passed_type = DECL_ARG_TYPE (parm);
4397 tree nominal_type = TREE_TYPE (parm);
4398 int last_named = 0, named_arg;
4401 int pretend_bytes = 0;
4403 /* Set LAST_NAMED if this is last named arg before last
4409 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4410 if (DECL_NAME (tem))
4416 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4417 most machines, if this is a varargs/stdarg function, then we treat
4418 the last named arg as if it were anonymous too. */
4419 named_arg = targetm.calls.strict_argument_naming (&args_so_far) ? 1 : ! last_named;
4421 if (TREE_TYPE (parm) == error_mark_node
4422 /* This can happen after weird syntax errors
4423 or if an enum type is defined among the parms. */
4424 || TREE_CODE (parm) != PARM_DECL
4425 || passed_type == NULL)
4427 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4428 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4429 TREE_USED (parm) = 1;
4433 /* Find mode of arg as it is passed, and mode of arg
4434 as it should be during execution of this function. */
4435 passed_mode = TYPE_MODE (passed_type);
4436 nominal_mode = TYPE_MODE (nominal_type);
4438 /* If the parm's mode is VOID, its value doesn't matter,
4439 and avoid the usual things like emit_move_insn that could crash. */
4440 if (nominal_mode == VOIDmode)
4442 SET_DECL_RTL (parm, const0_rtx);
4443 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4447 /* If the parm is to be passed as a transparent union, use the
4448 type of the first field for the tests below. We have already
4449 verified that the modes are the same. */
4450 if (DECL_TRANSPARENT_UNION (parm)
4451 || (TREE_CODE (passed_type) == UNION_TYPE
4452 && TYPE_TRANSPARENT_UNION (passed_type)))
4453 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4455 /* See if this arg was passed by invisible reference. It is if
4456 it is an object whose size depends on the contents of the
4457 object itself or if the machine requires these objects be passed
4460 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type))
4461 || TREE_ADDRESSABLE (passed_type)
4462 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4463 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4464 passed_type, named_arg)
4468 passed_type = nominal_type = build_pointer_type (passed_type);
4470 passed_mode = nominal_mode = Pmode;
4472 /* See if the frontend wants to pass this by invisible reference. */
4473 else if (passed_type != nominal_type
4474 && POINTER_TYPE_P (passed_type)
4475 && TREE_TYPE (passed_type) == nominal_type)
4477 nominal_type = passed_type;
4479 passed_mode = nominal_mode = Pmode;
4482 promoted_mode = passed_mode;
4484 if (targetm.calls.promote_function_args (TREE_TYPE (fndecl)))
4486 /* Compute the mode in which the arg is actually extended to. */
4487 unsignedp = TREE_UNSIGNED (passed_type);
4488 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4491 /* Let machine desc say which reg (if any) the parm arrives in.
4492 0 means it arrives on the stack. */
4493 #ifdef FUNCTION_INCOMING_ARG
4494 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4495 passed_type, named_arg);
4497 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4498 passed_type, named_arg);
4501 if (entry_parm == 0)
4502 promoted_mode = passed_mode;
4504 /* If this is the last named parameter, do any required setup for
4505 varargs or stdargs. We need to know about the case of this being an
4506 addressable type, in which case we skip the registers it
4507 would have arrived in.
4509 For stdargs, LAST_NAMED will be set for two parameters, the one that
4510 is actually the last named, and the dummy parameter. We only
4511 want to do this action once.
4513 Also, indicate when RTL generation is to be suppressed. */
4514 if (last_named && !varargs_setup)
4516 int varargs_pretend_bytes = 0;
4517 targetm.calls.setup_incoming_varargs (&args_so_far, promoted_mode,
4519 &varargs_pretend_bytes, 0);
4522 /* If the back-end has requested extra stack space, record how
4523 much is needed. Do not change pretend_args_size otherwise
4524 since it may be nonzero from an earlier partial argument. */
4525 if (varargs_pretend_bytes > 0)
4526 current_function_pretend_args_size = varargs_pretend_bytes;
4529 /* Determine parm's home in the stack,
4530 in case it arrives in the stack or we should pretend it did.
4532 Compute the stack position and rtx where the argument arrives
4535 There is one complexity here: If this was a parameter that would
4536 have been passed in registers, but wasn't only because it is
4537 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4538 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4539 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4540 0 as it was the previous time. */
4541 in_regs = entry_parm != 0;
4542 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4545 if (!in_regs && !named_arg)
4548 targetm.calls.pretend_outgoing_varargs_named (&args_so_far);
4551 #ifdef FUNCTION_INCOMING_ARG
4552 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4554 pretend_named) != 0;
4556 in_regs = FUNCTION_ARG (args_so_far, promoted_mode,
4558 pretend_named) != 0;
4563 /* If this parameter was passed both in registers and in the stack,
4564 use the copy on the stack. */
4565 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4568 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4571 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4572 passed_type, named_arg);
4574 #ifndef MAYBE_REG_PARM_STACK_SPACE
4575 /* The caller might already have allocated stack space
4576 for the register parameters. */
4577 && reg_parm_stack_space == 0
4581 /* Part of this argument is passed in registers and part
4582 is passed on the stack. Ask the prologue code to extend
4583 the stack part so that we can recreate the full value.
4585 PRETEND_BYTES is the size of the registers we need to store.
4586 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
4587 stack space that the prologue should allocate.
4589 Internally, gcc assumes that the argument pointer is
4590 aligned to STACK_BOUNDARY bits. This is used both for
4591 alignment optimizations (see init_emit) and to locate
4592 arguments that are aligned to more than PARM_BOUNDARY
4593 bits. We must preserve this invariant by rounding
4594 CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to a stack
4596 pretend_bytes = partial * UNITS_PER_WORD;
4597 current_function_pretend_args_size
4598 = CEIL_ROUND (pretend_bytes, STACK_BYTES);
4600 /* If PRETEND_BYTES != CURRENT_FUNCTION_PRETEND_ARGS_SIZE,
4601 insert the padding before the start of the first pretend
4603 stack_args_size.constant
4604 = (current_function_pretend_args_size - pretend_bytes);
4609 memset (&locate, 0, sizeof (locate));
4610 locate_and_pad_parm (promoted_mode, passed_type, in_regs,
4611 entry_parm ? partial : 0, fndecl,
4612 &stack_args_size, &locate);
4616 unsigned int align, boundary;
4618 /* If we're passing this arg using a reg, make its stack home
4619 the aligned stack slot. */
4621 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset);
4623 offset_rtx = ARGS_SIZE_RTX (locate.offset);
4625 if (offset_rtx == const0_rtx)
4626 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4628 stack_parm = gen_rtx_MEM (promoted_mode,
4629 gen_rtx_PLUS (Pmode,
4630 internal_arg_pointer,
4633 set_mem_attributes (stack_parm, parm, 1);
4635 boundary = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4638 /* If we're padding upward, we know that the alignment of the slot
4639 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
4640 intentionally forcing upward padding. Otherwise we have to come
4641 up with a guess at the alignment based on OFFSET_RTX. */
4642 if (locate.where_pad == upward || entry_parm)
4644 else if (GET_CODE (offset_rtx) == CONST_INT)
4646 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
4647 align = align & -align;
4650 set_mem_align (stack_parm, align);
4653 set_reg_attrs_for_parm (entry_parm, stack_parm);
4656 /* If this parm was passed part in regs and part in memory,
4657 pretend it arrived entirely in memory
4658 by pushing the register-part onto the stack.
4660 In the special case of a DImode or DFmode that is split,
4661 we could put it together in a pseudoreg directly,
4662 but for now that's not worth bothering with. */
4666 /* Handle calls that pass values in multiple non-contiguous
4667 locations. The Irix 6 ABI has examples of this. */
4668 if (GET_CODE (entry_parm) == PARALLEL)
4669 emit_group_store (validize_mem (stack_parm), entry_parm,
4671 int_size_in_bytes (TREE_TYPE (parm)));
4674 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
4677 entry_parm = stack_parm;
4680 /* If we didn't decide this parm came in a register,
4681 by default it came on the stack. */
4682 if (entry_parm == 0)
4683 entry_parm = stack_parm;
4685 /* Record permanently how this parm was passed. */
4686 DECL_INCOMING_RTL (parm) = entry_parm;
4688 /* If there is actually space on the stack for this parm,
4689 count it in stack_args_size; otherwise set stack_parm to 0
4690 to indicate there is no preallocated stack slot for the parm. */
4692 if (entry_parm == stack_parm
4693 || (GET_CODE (entry_parm) == PARALLEL
4694 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4695 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4696 /* On some machines, even if a parm value arrives in a register
4697 there is still an (uninitialized) stack slot allocated for it.
4699 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4700 whether this parameter already has a stack slot allocated,
4701 because an arg block exists only if current_function_args_size
4702 is larger than some threshold, and we haven't calculated that
4703 yet. So, for now, we just assume that stack slots never exist
4705 || REG_PARM_STACK_SPACE (fndecl) > 0
4709 stack_args_size.constant += pretend_bytes + locate.size.constant;
4710 if (locate.size.var)
4711 ADD_PARM_SIZE (stack_args_size, locate.size.var);
4714 /* No stack slot was pushed for this parm. */
4717 /* Update info on where next arg arrives in registers. */
4719 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4720 passed_type, named_arg);
4722 /* If we can't trust the parm stack slot to be aligned enough
4723 for its ultimate type, don't use that slot after entry.
4724 We'll make another stack slot, if we need one. */
4725 if (STRICT_ALIGNMENT && stack_parm
4726 && GET_MODE_ALIGNMENT (nominal_mode) > MEM_ALIGN (stack_parm))
4729 /* If parm was passed in memory, and we need to convert it on entry,
4730 don't store it back in that same slot. */
4731 if (entry_parm == stack_parm
4732 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4735 /* When an argument is passed in multiple locations, we can't
4736 make use of this information, but we can save some copying if
4737 the whole argument is passed in a single register. */
4738 if (GET_CODE (entry_parm) == PARALLEL
4739 && nominal_mode != BLKmode && passed_mode != BLKmode)
4741 int i, len = XVECLEN (entry_parm, 0);
4743 for (i = 0; i < len; i++)
4744 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4745 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4746 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4748 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4750 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4751 DECL_INCOMING_RTL (parm) = entry_parm;
4756 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4757 in the mode in which it arrives.
4758 STACK_PARM is an RTX for a stack slot where the parameter can live
4759 during the function (in case we want to put it there).
4760 STACK_PARM is 0 if no stack slot was pushed for it.
4762 Now output code if necessary to convert ENTRY_PARM to
4763 the type in which this function declares it,
4764 and store that result in an appropriate place,
4765 which may be a pseudo reg, may be STACK_PARM,
4766 or may be a local stack slot if STACK_PARM is 0.
4768 Set DECL_RTL to that place. */
4770 if (GET_CODE (entry_parm) == PARALLEL && nominal_mode != BLKmode
4771 && XVECLEN (entry_parm, 0) > 1)
4773 /* Reconstitute objects the size of a register or larger using
4774 register operations instead of the stack. */
4775 rtx parmreg = gen_reg_rtx (nominal_mode);
4777 if (REG_P (parmreg))
4779 unsigned int regno = REGNO (parmreg);
4781 emit_group_store (parmreg, entry_parm, TREE_TYPE (parm),
4782 int_size_in_bytes (TREE_TYPE (parm)));
4783 SET_DECL_RTL (parm, parmreg);
4785 if (regno >= max_parm_reg)
4788 int old_max_parm_reg = max_parm_reg;
4790 /* It's slow to expand this one register at a time,
4791 but it's also rare and we need max_parm_reg to be
4792 precisely correct. */
4793 max_parm_reg = regno + 1;
4794 new = ggc_realloc (parm_reg_stack_loc,
4795 max_parm_reg * sizeof (rtx));
4796 memset (new + old_max_parm_reg, 0,
4797 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4798 parm_reg_stack_loc = new;
4799 parm_reg_stack_loc[regno] = stack_parm;
4804 if (nominal_mode == BLKmode
4805 #ifdef BLOCK_REG_PADDING
4806 || (locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward)
4807 && GET_MODE_SIZE (promoted_mode) < UNITS_PER_WORD)
4809 || GET_CODE (entry_parm) == PARALLEL)
4811 /* If a BLKmode arrives in registers, copy it to a stack slot.
4812 Handle calls that pass values in multiple non-contiguous
4813 locations. The Irix 6 ABI has examples of this. */
4814 if (GET_CODE (entry_parm) == REG
4815 || GET_CODE (entry_parm) == PARALLEL)
4817 int size = int_size_in_bytes (TREE_TYPE (parm));
4818 int size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
4821 /* Note that we will be storing an integral number of words.
4822 So we have to be careful to ensure that we allocate an
4823 integral number of words. We do this below in the
4824 assign_stack_local if space was not allocated in the argument
4825 list. If it was, this will not work if PARM_BOUNDARY is not
4826 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4827 if it becomes a problem. Exception is when BLKmode arrives
4828 with arguments not conforming to word_mode. */
4830 if (stack_parm == 0)
4832 stack_parm = assign_stack_local (BLKmode, size_stored, 0);
4833 PUT_MODE (stack_parm, GET_MODE (entry_parm));
4834 set_mem_attributes (stack_parm, parm, 1);
4836 else if (GET_CODE (entry_parm) == PARALLEL)
4838 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4841 mem = validize_mem (stack_parm);
4843 /* Handle calls that pass values in multiple non-contiguous
4844 locations. The Irix 6 ABI has examples of this. */
4845 if (GET_CODE (entry_parm) == PARALLEL)
4846 emit_group_store (mem, entry_parm, TREE_TYPE (parm), size);
4851 /* If SIZE is that of a mode no bigger than a word, just use
4852 that mode's store operation. */
4853 else if (size <= UNITS_PER_WORD)
4855 enum machine_mode mode
4856 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
4859 #ifdef BLOCK_REG_PADDING
4860 && (size == UNITS_PER_WORD
4861 || (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4862 != (BYTES_BIG_ENDIAN ? upward : downward)))
4866 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
4867 emit_move_insn (change_address (mem, mode, 0), reg);
4870 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
4871 machine must be aligned to the left before storing
4872 to memory. Note that the previous test doesn't
4873 handle all cases (e.g. SIZE == 3). */
4874 else if (size != UNITS_PER_WORD
4875 #ifdef BLOCK_REG_PADDING
4876 && (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4884 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4885 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
4887 x = expand_binop (word_mode, ashl_optab, reg,
4888 GEN_INT (by), 0, 1, OPTAB_WIDEN);
4889 tem = change_address (mem, word_mode, 0);
4890 emit_move_insn (tem, x);
4893 move_block_from_reg (REGNO (entry_parm), mem,
4894 size_stored / UNITS_PER_WORD);
4897 move_block_from_reg (REGNO (entry_parm), mem,
4898 size_stored / UNITS_PER_WORD);
4900 /* If parm is already bound to register pair, don't change
4902 if (! DECL_RTL_SET_P (parm))
4903 SET_DECL_RTL (parm, stack_parm);
4905 else if (! ((! optimize
4906 && ! DECL_REGISTER (parm))
4907 || TREE_SIDE_EFFECTS (parm)
4908 /* If -ffloat-store specified, don't put explicit
4909 float variables into registers. */
4910 || (flag_float_store
4911 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4912 /* Always assign pseudo to structure return or item passed
4913 by invisible reference. */
4914 || passed_pointer || parm == function_result_decl)
4916 /* Store the parm in a pseudoregister during the function, but we
4917 may need to do it in a wider mode. */
4920 unsigned int regno, regnoi = 0, regnor = 0;
4922 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4924 promoted_nominal_mode
4925 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4927 parmreg = gen_reg_rtx (promoted_nominal_mode);
4928 mark_user_reg (parmreg);
4930 /* If this was an item that we received a pointer to, set DECL_RTL
4934 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4936 set_mem_attributes (x, parm, 1);
4937 SET_DECL_RTL (parm, x);
4941 SET_DECL_RTL (parm, parmreg);
4942 maybe_set_unchanging (DECL_RTL (parm), parm);
4945 /* Copy the value into the register. */
4946 if (nominal_mode != passed_mode
4947 || promoted_nominal_mode != promoted_mode)
4950 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4951 mode, by the caller. We now have to convert it to
4952 NOMINAL_MODE, if different. However, PARMREG may be in
4953 a different mode than NOMINAL_MODE if it is being stored
4956 If ENTRY_PARM is a hard register, it might be in a register
4957 not valid for operating in its mode (e.g., an odd-numbered
4958 register for a DFmode). In that case, moves are the only
4959 thing valid, so we can't do a convert from there. This
4960 occurs when the calling sequence allow such misaligned
4963 In addition, the conversion may involve a call, which could
4964 clobber parameters which haven't been copied to pseudo
4965 registers yet. Therefore, we must first copy the parm to
4966 a pseudo reg here, and save the conversion until after all
4967 parameters have been moved. */
4969 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4971 emit_move_insn (tempreg, validize_mem (entry_parm));
4973 push_to_sequence (conversion_insns);
4974 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4976 if (GET_CODE (tempreg) == SUBREG
4977 && GET_MODE (tempreg) == nominal_mode
4978 && GET_CODE (SUBREG_REG (tempreg)) == REG
4979 && nominal_mode == passed_mode
4980 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4981 && GET_MODE_SIZE (GET_MODE (tempreg))
4982 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4984 /* The argument is already sign/zero extended, so note it
4986 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4987 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4990 /* TREE_USED gets set erroneously during expand_assignment. */
4991 save_tree_used = TREE_USED (parm);
4992 expand_assignment (parm,
4993 make_tree (nominal_type, tempreg), 0);
4994 TREE_USED (parm) = save_tree_used;
4995 conversion_insns = get_insns ();
5000 emit_move_insn (parmreg, validize_mem (entry_parm));
5002 /* If we were passed a pointer but the actual value
5003 can safely live in a register, put it in one. */
5004 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
5005 /* If by-reference argument was promoted, demote it. */
5006 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
5008 && ! DECL_REGISTER (parm))
5009 || TREE_SIDE_EFFECTS (parm)
5010 /* If -ffloat-store specified, don't put explicit
5011 float variables into registers. */
5012 || (flag_float_store
5013 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
5015 /* We can't use nominal_mode, because it will have been set to
5016 Pmode above. We must use the actual mode of the parm. */
5017 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
5018 mark_user_reg (parmreg);
5019 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
5021 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
5022 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
5023 push_to_sequence (conversion_insns);
5024 emit_move_insn (tempreg, DECL_RTL (parm));
5026 convert_to_mode (GET_MODE (parmreg),
5029 emit_move_insn (parmreg, DECL_RTL (parm));
5030 conversion_insns = get_insns();
5035 emit_move_insn (parmreg, DECL_RTL (parm));
5036 SET_DECL_RTL (parm, parmreg);
5037 /* STACK_PARM is the pointer, not the parm, and PARMREG is
5041 #ifdef FUNCTION_ARG_CALLEE_COPIES
5042 /* If we are passed an arg by reference and it is our responsibility
5043 to make a copy, do it now.
5044 PASSED_TYPE and PASSED mode now refer to the pointer, not the
5045 original argument, so we must recreate them in the call to
5046 FUNCTION_ARG_CALLEE_COPIES. */
5047 /* ??? Later add code to handle the case that if the argument isn't
5048 modified, don't do the copy. */
5050 else if (passed_pointer
5051 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
5052 TYPE_MODE (TREE_TYPE (passed_type)),
5053 TREE_TYPE (passed_type),
5055 && ! TREE_ADDRESSABLE (TREE_TYPE (passed_type)))
5058 tree type = TREE_TYPE (passed_type);
5060 /* This sequence may involve a library call perhaps clobbering
5061 registers that haven't been copied to pseudos yet. */
5063 push_to_sequence (conversion_insns);
5065 if (!COMPLETE_TYPE_P (type)
5066 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5067 /* This is a variable sized object. */
5068 copy = gen_rtx_MEM (BLKmode,
5069 allocate_dynamic_stack_space
5070 (expr_size (parm), NULL_RTX,
5071 TYPE_ALIGN (type)));
5073 copy = assign_stack_temp (TYPE_MODE (type),
5074 int_size_in_bytes (type), 1);
5075 set_mem_attributes (copy, parm, 1);
5077 store_expr (parm, copy, 0);
5078 emit_move_insn (parmreg, XEXP (copy, 0));
5079 conversion_insns = get_insns ();
5083 #endif /* FUNCTION_ARG_CALLEE_COPIES */
5085 /* In any case, record the parm's desired stack location
5086 in case we later discover it must live in the stack.
5088 If it is a COMPLEX value, store the stack location for both
5091 if (GET_CODE (parmreg) == CONCAT)
5092 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
5094 regno = REGNO (parmreg);
5096 if (regno >= max_parm_reg)
5099 int old_max_parm_reg = max_parm_reg;
5101 /* It's slow to expand this one register at a time,
5102 but it's also rare and we need max_parm_reg to be
5103 precisely correct. */
5104 max_parm_reg = regno + 1;
5105 new = ggc_realloc (parm_reg_stack_loc,
5106 max_parm_reg * sizeof (rtx));
5107 memset (new + old_max_parm_reg, 0,
5108 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
5109 parm_reg_stack_loc = new;
5112 if (GET_CODE (parmreg) == CONCAT)
5114 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
5116 regnor = REGNO (gen_realpart (submode, parmreg));
5117 regnoi = REGNO (gen_imagpart (submode, parmreg));
5119 if (stack_parm != 0)
5121 parm_reg_stack_loc[regnor]
5122 = gen_realpart (submode, stack_parm);
5123 parm_reg_stack_loc[regnoi]
5124 = gen_imagpart (submode, stack_parm);
5128 parm_reg_stack_loc[regnor] = 0;
5129 parm_reg_stack_loc[regnoi] = 0;
5133 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
5135 /* Mark the register as eliminable if we did no conversion
5136 and it was copied from memory at a fixed offset,
5137 and the arg pointer was not copied to a pseudo-reg.
5138 If the arg pointer is a pseudo reg or the offset formed
5139 an invalid address, such memory-equivalences
5140 as we make here would screw up life analysis for it. */
5141 if (nominal_mode == passed_mode
5144 && GET_CODE (stack_parm) == MEM
5145 && locate.offset.var == 0
5146 && reg_mentioned_p (virtual_incoming_args_rtx,
5147 XEXP (stack_parm, 0)))
5149 rtx linsn = get_last_insn ();
5152 /* Mark complex types separately. */
5153 if (GET_CODE (parmreg) == CONCAT)
5154 /* Scan backwards for the set of the real and
5156 for (sinsn = linsn; sinsn != 0;
5157 sinsn = prev_nonnote_insn (sinsn))
5159 set = single_set (sinsn);
5161 && SET_DEST (set) == regno_reg_rtx [regnoi])
5163 = gen_rtx_EXPR_LIST (REG_EQUIV,
5164 parm_reg_stack_loc[regnoi],
5167 && SET_DEST (set) == regno_reg_rtx [regnor])
5169 = gen_rtx_EXPR_LIST (REG_EQUIV,
5170 parm_reg_stack_loc[regnor],
5173 else if ((set = single_set (linsn)) != 0
5174 && SET_DEST (set) == parmreg)
5176 = gen_rtx_EXPR_LIST (REG_EQUIV,
5177 stack_parm, REG_NOTES (linsn));
5180 /* For pointer data type, suggest pointer register. */
5181 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5182 mark_reg_pointer (parmreg,
5183 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5185 /* If something wants our address, try to use ADDRESSOF. */
5186 if (TREE_ADDRESSABLE (parm))
5188 /* If we end up putting something into the stack,
5189 fixup_var_refs_insns will need to make a pass over
5190 all the instructions. It looks through the pending
5191 sequences -- but it can't see the ones in the
5192 CONVERSION_INSNS, if they're not on the sequence
5193 stack. So, we go back to that sequence, just so that
5194 the fixups will happen. */
5195 push_to_sequence (conversion_insns);
5196 put_var_into_stack (parm, /*rescan=*/true);
5197 conversion_insns = get_insns ();
5203 /* Value must be stored in the stack slot STACK_PARM
5204 during function execution. */
5206 if (promoted_mode != nominal_mode)
5208 /* Conversion is required. */
5209 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5211 emit_move_insn (tempreg, validize_mem (entry_parm));
5213 push_to_sequence (conversion_insns);
5214 entry_parm = convert_to_mode (nominal_mode, tempreg,
5215 TREE_UNSIGNED (TREE_TYPE (parm)));
5217 /* ??? This may need a big-endian conversion on sparc64. */
5218 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5220 conversion_insns = get_insns ();
5225 if (entry_parm != stack_parm)
5227 if (stack_parm == 0)
5230 = assign_stack_local (GET_MODE (entry_parm),
5231 GET_MODE_SIZE (GET_MODE (entry_parm)),
5233 set_mem_attributes (stack_parm, parm, 1);
5236 if (promoted_mode != nominal_mode)
5238 push_to_sequence (conversion_insns);
5239 emit_move_insn (validize_mem (stack_parm),
5240 validize_mem (entry_parm));
5241 conversion_insns = get_insns ();
5245 emit_move_insn (validize_mem (stack_parm),
5246 validize_mem (entry_parm));
5249 SET_DECL_RTL (parm, stack_parm);
5253 if (targetm.calls.split_complex_arg && fnargs != orig_fnargs)
5255 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
5257 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
5258 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
5260 rtx tmp, real, imag;
5261 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
5263 real = DECL_RTL (fnargs);
5264 imag = DECL_RTL (TREE_CHAIN (fnargs));
5265 if (inner != GET_MODE (real))
5267 real = gen_lowpart_SUBREG (inner, real);
5268 imag = gen_lowpart_SUBREG (inner, imag);
5270 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
5271 SET_DECL_RTL (parm, tmp);
5273 real = DECL_INCOMING_RTL (fnargs);
5274 imag = DECL_INCOMING_RTL (TREE_CHAIN (fnargs));
5275 if (inner != GET_MODE (real))
5277 real = gen_lowpart_SUBREG (inner, real);
5278 imag = gen_lowpart_SUBREG (inner, imag);
5280 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
5281 DECL_INCOMING_RTL (parm) = tmp;
5282 fnargs = TREE_CHAIN (fnargs);
5286 SET_DECL_RTL (parm, DECL_RTL (fnargs));
5287 DECL_INCOMING_RTL (parm) = DECL_INCOMING_RTL (fnargs);
5289 fnargs = TREE_CHAIN (fnargs);
5293 /* Output all parameter conversion instructions (possibly including calls)
5294 now that all parameters have been copied out of hard registers. */
5295 emit_insn (conversion_insns);
5297 /* If we are receiving a struct value address as the first argument, set up
5298 the RTL for the function result. As this might require code to convert
5299 the transmitted address to Pmode, we do this here to ensure that possible
5300 preliminary conversions of the address have been emitted already. */
5301 if (function_result_decl)
5303 tree result = DECL_RESULT (fndecl);
5304 rtx addr = DECL_RTL (function_result_decl);
5307 addr = convert_memory_address (Pmode, addr);
5308 x = gen_rtx_MEM (DECL_MODE (result), addr);
5309 set_mem_attributes (x, result, 1);
5310 SET_DECL_RTL (result, x);
5313 last_parm_insn = get_last_insn ();
5315 current_function_args_size = stack_args_size.constant;
5317 /* Adjust function incoming argument size for alignment and
5320 #ifdef REG_PARM_STACK_SPACE
5321 #ifndef MAYBE_REG_PARM_STACK_SPACE
5322 current_function_args_size = MAX (current_function_args_size,
5323 REG_PARM_STACK_SPACE (fndecl));
5327 current_function_args_size
5328 = ((current_function_args_size + STACK_BYTES - 1)
5329 / STACK_BYTES) * STACK_BYTES;
5331 #ifdef ARGS_GROW_DOWNWARD
5332 current_function_arg_offset_rtx
5333 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5334 : expand_expr (size_diffop (stack_args_size.var,
5335 size_int (-stack_args_size.constant)),
5336 NULL_RTX, VOIDmode, 0));
5338 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5341 /* See how many bytes, if any, of its args a function should try to pop
5344 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5345 current_function_args_size);
5347 /* For stdarg.h function, save info about
5348 regs and stack space used by the named args. */
5350 current_function_args_info = args_so_far;
5352 /* Set the rtx used for the function return value. Put this in its
5353 own variable so any optimizers that need this information don't have
5354 to include tree.h. Do this here so it gets done when an inlined
5355 function gets output. */
5357 current_function_return_rtx
5358 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5359 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5361 /* If scalar return value was computed in a pseudo-reg, or was a named
5362 return value that got dumped to the stack, copy that to the hard
5364 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5366 tree decl_result = DECL_RESULT (fndecl);
5367 rtx decl_rtl = DECL_RTL (decl_result);
5369 if (REG_P (decl_rtl)
5370 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5371 : DECL_REGISTER (decl_result))
5375 #ifdef FUNCTION_OUTGOING_VALUE
5376 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5379 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5382 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5383 /* The delay slot scheduler assumes that current_function_return_rtx
5384 holds the hard register containing the return value, not a
5385 temporary pseudo. */
5386 current_function_return_rtx = real_decl_rtl;
5391 /* If ARGS contains entries with complex types, split the entry into two
5392 entries of the component type. Return a new list of substitutions are
5393 needed, else the old list. */
5396 split_complex_args (tree args)
5400 /* Before allocating memory, check for the common case of no complex. */
5401 for (p = args; p; p = TREE_CHAIN (p))
5403 tree type = TREE_TYPE (p);
5404 if (TREE_CODE (type) == COMPLEX_TYPE
5405 && targetm.calls.split_complex_arg (type))
5411 args = copy_list (args);
5413 for (p = args; p; p = TREE_CHAIN (p))
5415 tree type = TREE_TYPE (p);
5416 if (TREE_CODE (type) == COMPLEX_TYPE
5417 && targetm.calls.split_complex_arg (type))
5420 tree subtype = TREE_TYPE (type);
5422 /* Rewrite the PARM_DECL's type with its component. */
5423 TREE_TYPE (p) = subtype;
5424 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
5425 DECL_MODE (p) = VOIDmode;
5426 DECL_SIZE (p) = NULL;
5427 DECL_SIZE_UNIT (p) = NULL;
5430 /* Build a second synthetic decl. */
5431 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
5432 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
5433 layout_decl (decl, 0);
5435 /* Splice it in; skip the new decl. */
5436 TREE_CHAIN (decl) = TREE_CHAIN (p);
5437 TREE_CHAIN (p) = decl;
5445 /* Indicate whether REGNO is an incoming argument to the current function
5446 that was promoted to a wider mode. If so, return the RTX for the
5447 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5448 that REGNO is promoted from and whether the promotion was signed or
5452 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
5456 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5457 arg = TREE_CHAIN (arg))
5458 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5459 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5460 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5462 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5463 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5465 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5466 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5467 && mode != DECL_MODE (arg))
5469 *pmode = DECL_MODE (arg);
5470 *punsignedp = unsignedp;
5471 return DECL_INCOMING_RTL (arg);
5479 /* Compute the size and offset from the start of the stacked arguments for a
5480 parm passed in mode PASSED_MODE and with type TYPE.
5482 INITIAL_OFFSET_PTR points to the current offset into the stacked
5485 The starting offset and size for this parm are returned in
5486 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5487 nonzero, the offset is that of stack slot, which is returned in
5488 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5489 padding required from the initial offset ptr to the stack slot.
5491 IN_REGS is nonzero if the argument will be passed in registers. It will
5492 never be set if REG_PARM_STACK_SPACE is not defined.
5494 FNDECL is the function in which the argument was defined.
5496 There are two types of rounding that are done. The first, controlled by
5497 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5498 list to be aligned to the specific boundary (in bits). This rounding
5499 affects the initial and starting offsets, but not the argument size.
5501 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5502 optionally rounds the size of the parm to PARM_BOUNDARY. The
5503 initial offset is not affected by this rounding, while the size always
5504 is and the starting offset may be. */
5506 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5507 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5508 callers pass in the total size of args so far as
5509 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5512 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
5513 int partial, tree fndecl ATTRIBUTE_UNUSED,
5514 struct args_size *initial_offset_ptr,
5515 struct locate_and_pad_arg_data *locate)
5518 enum direction where_pad;
5520 int reg_parm_stack_space = 0;
5521 int part_size_in_regs;
5523 #ifdef REG_PARM_STACK_SPACE
5524 #ifdef MAYBE_REG_PARM_STACK_SPACE
5525 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5527 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5530 /* If we have found a stack parm before we reach the end of the
5531 area reserved for registers, skip that area. */
5534 if (reg_parm_stack_space > 0)
5536 if (initial_offset_ptr->var)
5538 initial_offset_ptr->var
5539 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5540 ssize_int (reg_parm_stack_space));
5541 initial_offset_ptr->constant = 0;
5543 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5544 initial_offset_ptr->constant = reg_parm_stack_space;
5547 #endif /* REG_PARM_STACK_SPACE */
5549 part_size_in_regs = 0;
5550 if (reg_parm_stack_space == 0)
5551 part_size_in_regs = ((partial * UNITS_PER_WORD)
5552 / (PARM_BOUNDARY / BITS_PER_UNIT)
5553 * (PARM_BOUNDARY / BITS_PER_UNIT));
5556 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5557 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5558 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5559 locate->where_pad = where_pad;
5561 #ifdef ARGS_GROW_DOWNWARD
5562 locate->slot_offset.constant = -initial_offset_ptr->constant;
5563 if (initial_offset_ptr->var)
5564 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
5565 initial_offset_ptr->var);
5569 if (where_pad != none
5570 && (!host_integerp (sizetree, 1)
5571 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5572 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5573 SUB_PARM_SIZE (locate->slot_offset, s2);
5576 locate->slot_offset.constant += part_size_in_regs;
5579 #ifdef REG_PARM_STACK_SPACE
5580 || REG_PARM_STACK_SPACE (fndecl) > 0
5583 pad_to_arg_alignment (&locate->slot_offset, boundary,
5584 &locate->alignment_pad);
5586 locate->size.constant = (-initial_offset_ptr->constant
5587 - locate->slot_offset.constant);
5588 if (initial_offset_ptr->var)
5589 locate->size.var = size_binop (MINUS_EXPR,
5590 size_binop (MINUS_EXPR,
5592 initial_offset_ptr->var),
5593 locate->slot_offset.var);
5595 /* Pad_below needs the pre-rounded size to know how much to pad
5597 locate->offset = locate->slot_offset;
5598 if (where_pad == downward)
5599 pad_below (&locate->offset, passed_mode, sizetree);
5601 #else /* !ARGS_GROW_DOWNWARD */
5603 #ifdef REG_PARM_STACK_SPACE
5604 || REG_PARM_STACK_SPACE (fndecl) > 0
5607 pad_to_arg_alignment (initial_offset_ptr, boundary,
5608 &locate->alignment_pad);
5609 locate->slot_offset = *initial_offset_ptr;
5611 #ifdef PUSH_ROUNDING
5612 if (passed_mode != BLKmode)
5613 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5616 /* Pad_below needs the pre-rounded size to know how much to pad below
5617 so this must be done before rounding up. */
5618 locate->offset = locate->slot_offset;
5619 if (where_pad == downward)
5620 pad_below (&locate->offset, passed_mode, sizetree);
5622 if (where_pad != none
5623 && (!host_integerp (sizetree, 1)
5624 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5625 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5627 ADD_PARM_SIZE (locate->size, sizetree);
5629 locate->size.constant -= part_size_in_regs;
5630 #endif /* ARGS_GROW_DOWNWARD */
5633 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5634 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5637 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
5638 struct args_size *alignment_pad)
5640 tree save_var = NULL_TREE;
5641 HOST_WIDE_INT save_constant = 0;
5642 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5643 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
5645 #ifdef SPARC_STACK_BOUNDARY_HACK
5646 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
5647 higher than the real alignment of %sp. However, when it does this,
5648 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
5649 This is a temporary hack while the sparc port is fixed. */
5650 if (SPARC_STACK_BOUNDARY_HACK)
5654 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5656 save_var = offset_ptr->var;
5657 save_constant = offset_ptr->constant;
5660 alignment_pad->var = NULL_TREE;
5661 alignment_pad->constant = 0;
5663 if (boundary > BITS_PER_UNIT)
5665 if (offset_ptr->var)
5667 tree sp_offset_tree = ssize_int (sp_offset);
5668 tree offset = size_binop (PLUS_EXPR,
5669 ARGS_SIZE_TREE (*offset_ptr),
5671 #ifdef ARGS_GROW_DOWNWARD
5672 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
5674 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
5677 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
5678 /* ARGS_SIZE_TREE includes constant term. */
5679 offset_ptr->constant = 0;
5680 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5681 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5686 offset_ptr->constant = -sp_offset +
5687 #ifdef ARGS_GROW_DOWNWARD
5688 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5690 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5692 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5693 alignment_pad->constant = offset_ptr->constant - save_constant;
5699 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
5701 if (passed_mode != BLKmode)
5703 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5704 offset_ptr->constant
5705 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5706 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5707 - GET_MODE_SIZE (passed_mode));
5711 if (TREE_CODE (sizetree) != INTEGER_CST
5712 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5714 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5715 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5717 ADD_PARM_SIZE (*offset_ptr, s2);
5718 SUB_PARM_SIZE (*offset_ptr, sizetree);
5723 /* Walk the tree of blocks describing the binding levels within a function
5724 and warn about uninitialized variables.
5725 This is done after calling flow_analysis and before global_alloc
5726 clobbers the pseudo-regs to hard regs. */
5729 uninitialized_vars_warning (tree block)
5732 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5734 if (warn_uninitialized
5735 && TREE_CODE (decl) == VAR_DECL
5736 /* These warnings are unreliable for and aggregates
5737 because assigning the fields one by one can fail to convince
5738 flow.c that the entire aggregate was initialized.
5739 Unions are troublesome because members may be shorter. */
5740 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5741 && DECL_RTL_SET_P (decl)
5742 && GET_CODE (DECL_RTL (decl)) == REG
5743 /* Global optimizations can make it difficult to determine if a
5744 particular variable has been initialized. However, a VAR_DECL
5745 with a nonzero DECL_INITIAL had an initializer, so do not
5746 claim it is potentially uninitialized.
5748 When the DECL_INITIAL is NULL call the language hook to tell us
5749 if we want to warn. */
5750 && (DECL_INITIAL (decl) == NULL_TREE || lang_hooks.decl_uninit (decl))
5751 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5752 warning ("%J'%D' might be used uninitialized in this function",
5755 && TREE_CODE (decl) == VAR_DECL
5756 && DECL_RTL_SET_P (decl)
5757 && GET_CODE (DECL_RTL (decl)) == REG
5758 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5759 warning ("%Jvariable '%D' might be clobbered by `longjmp' or `vfork'",
5762 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5763 uninitialized_vars_warning (sub);
5766 /* Do the appropriate part of uninitialized_vars_warning
5767 but for arguments instead of local variables. */
5770 setjmp_args_warning (void)
5773 for (decl = DECL_ARGUMENTS (current_function_decl);
5774 decl; decl = TREE_CHAIN (decl))
5775 if (DECL_RTL (decl) != 0
5776 && GET_CODE (DECL_RTL (decl)) == REG
5777 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5778 warning ("%Jargument '%D' might be clobbered by `longjmp' or `vfork'",
5782 /* If this function call setjmp, put all vars into the stack
5783 unless they were declared `register'. */
5786 setjmp_protect (tree block)
5789 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5790 if ((TREE_CODE (decl) == VAR_DECL
5791 || TREE_CODE (decl) == PARM_DECL)
5792 && DECL_RTL (decl) != 0
5793 && (GET_CODE (DECL_RTL (decl)) == REG
5794 || (GET_CODE (DECL_RTL (decl)) == MEM
5795 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5796 /* If this variable came from an inline function, it must be
5797 that its life doesn't overlap the setjmp. If there was a
5798 setjmp in the function, it would already be in memory. We
5799 must exclude such variable because their DECL_RTL might be
5800 set to strange things such as virtual_stack_vars_rtx. */
5801 && ! DECL_FROM_INLINE (decl)
5803 #ifdef NON_SAVING_SETJMP
5804 /* If longjmp doesn't restore the registers,
5805 don't put anything in them. */
5809 ! DECL_REGISTER (decl)))
5810 put_var_into_stack (decl, /*rescan=*/true);
5811 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5812 setjmp_protect (sub);
5815 /* Like the previous function, but for args instead of local variables. */
5818 setjmp_protect_args (void)
5821 for (decl = DECL_ARGUMENTS (current_function_decl);
5822 decl; decl = TREE_CHAIN (decl))
5823 if ((TREE_CODE (decl) == VAR_DECL
5824 || TREE_CODE (decl) == PARM_DECL)
5825 && DECL_RTL (decl) != 0
5826 && (GET_CODE (DECL_RTL (decl)) == REG
5827 || (GET_CODE (DECL_RTL (decl)) == MEM
5828 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5830 /* If longjmp doesn't restore the registers,
5831 don't put anything in them. */
5832 #ifdef NON_SAVING_SETJMP
5836 ! DECL_REGISTER (decl)))
5837 put_var_into_stack (decl, /*rescan=*/true);
5840 /* Return the context-pointer register corresponding to DECL,
5841 or 0 if it does not need one. */
5844 lookup_static_chain (tree decl)
5846 tree context = decl_function_context (decl);
5850 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5853 /* We treat inline_function_decl as an alias for the current function
5854 because that is the inline function whose vars, types, etc.
5855 are being merged into the current function.
5856 See expand_inline_function. */
5857 if (context == current_function_decl || context == inline_function_decl)
5858 return virtual_stack_vars_rtx;
5860 for (link = context_display; link; link = TREE_CHAIN (link))
5861 if (TREE_PURPOSE (link) == context)
5862 return RTL_EXPR_RTL (TREE_VALUE (link));
5867 /* Convert a stack slot address ADDR for variable VAR
5868 (from a containing function)
5869 into an address valid in this function (using a static chain). */
5872 fix_lexical_addr (rtx addr, tree var)
5875 HOST_WIDE_INT displacement;
5876 tree context = decl_function_context (var);
5877 struct function *fp;
5880 /* If this is the present function, we need not do anything. */
5881 if (context == current_function_decl || context == inline_function_decl)
5884 fp = find_function_data (context);
5886 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5887 addr = XEXP (XEXP (addr, 0), 0);
5889 /* Decode given address as base reg plus displacement. */
5890 if (GET_CODE (addr) == REG)
5891 basereg = addr, displacement = 0;
5892 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5893 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5897 /* We accept vars reached via the containing function's
5898 incoming arg pointer and via its stack variables pointer. */
5899 if (basereg == fp->internal_arg_pointer)
5901 /* If reached via arg pointer, get the arg pointer value
5902 out of that function's stack frame.
5904 There are two cases: If a separate ap is needed, allocate a
5905 slot in the outer function for it and dereference it that way.
5906 This is correct even if the real ap is actually a pseudo.
5907 Otherwise, just adjust the offset from the frame pointer to
5910 #ifdef NEED_SEPARATE_AP
5913 addr = get_arg_pointer_save_area (fp);
5914 addr = fix_lexical_addr (XEXP (addr, 0), var);
5915 addr = memory_address (Pmode, addr);
5917 base = gen_rtx_MEM (Pmode, addr);
5918 set_mem_alias_set (base, get_frame_alias_set ());
5919 base = copy_to_reg (base);
5921 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5922 base = lookup_static_chain (var);
5926 else if (basereg == virtual_stack_vars_rtx)
5928 /* This is the same code as lookup_static_chain, duplicated here to
5929 avoid an extra call to decl_function_context. */
5932 for (link = context_display; link; link = TREE_CHAIN (link))
5933 if (TREE_PURPOSE (link) == context)
5935 base = RTL_EXPR_RTL (TREE_VALUE (link));
5943 /* Use same offset, relative to appropriate static chain or argument
5945 return plus_constant (base, displacement);
5948 /* Return the address of the trampoline for entering nested fn FUNCTION.
5949 If necessary, allocate a trampoline (in the stack frame)
5950 and emit rtl to initialize its contents (at entry to this function). */
5953 trampoline_address (tree function)
5958 struct function *fp;
5961 /* Find an existing trampoline and return it. */
5962 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5963 if (TREE_PURPOSE (link) == function)
5965 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5967 for (fp = outer_function_chain; fp; fp = fp->outer)
5968 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5969 if (TREE_PURPOSE (link) == function)
5971 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5973 return adjust_trampoline_addr (tramp);
5976 /* None exists; we must make one. */
5978 /* Find the `struct function' for the function containing FUNCTION. */
5980 fn_context = decl_function_context (function);
5981 if (fn_context != current_function_decl
5982 && fn_context != inline_function_decl)
5983 fp = find_function_data (fn_context);
5985 /* Allocate run-time space for this trampoline. */
5986 /* If rounding needed, allocate extra space
5987 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5988 #define TRAMPOLINE_REAL_SIZE \
5989 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5990 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5992 /* Record the trampoline for reuse and note it for later initialization
5993 by expand_function_end. */
5996 rtlexp = make_node (RTL_EXPR);
5997 RTL_EXPR_RTL (rtlexp) = tramp;
5998 fp->x_trampoline_list = tree_cons (function, rtlexp,
5999 fp->x_trampoline_list);
6003 /* Make the RTL_EXPR node temporary, not momentary, so that the
6004 trampoline_list doesn't become garbage. */
6005 rtlexp = make_node (RTL_EXPR);
6007 RTL_EXPR_RTL (rtlexp) = tramp;
6008 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
6011 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
6012 return adjust_trampoline_addr (tramp);
6015 /* Given a trampoline address,
6016 round it to multiple of TRAMPOLINE_ALIGNMENT. */
6019 round_trampoline_addr (rtx tramp)
6021 /* Round address up to desired boundary. */
6022 rtx temp = gen_reg_rtx (Pmode);
6023 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
6024 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
6026 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
6027 temp, 0, OPTAB_LIB_WIDEN);
6028 tramp = expand_simple_binop (Pmode, AND, temp, mask,
6029 temp, 0, OPTAB_LIB_WIDEN);
6034 /* Given a trampoline address, round it then apply any
6035 platform-specific adjustments so that the result can be used for a
6039 adjust_trampoline_addr (rtx tramp)
6041 tramp = round_trampoline_addr (tramp);
6042 #ifdef TRAMPOLINE_ADJUST_ADDRESS
6043 TRAMPOLINE_ADJUST_ADDRESS (tramp);
6048 /* Put all this function's BLOCK nodes including those that are chained
6049 onto the first block into a vector, and return it.
6050 Also store in each NOTE for the beginning or end of a block
6051 the index of that block in the vector.
6052 The arguments are BLOCK, the chain of top-level blocks of the function,
6053 and INSNS, the insn chain of the function. */
6056 identify_blocks (void)
6059 tree *block_vector, *last_block_vector;
6061 tree block = DECL_INITIAL (current_function_decl);
6066 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
6067 depth-first order. */
6068 block_vector = get_block_vector (block, &n_blocks);
6069 block_stack = xmalloc (n_blocks * sizeof (tree));
6071 last_block_vector = identify_blocks_1 (get_insns (),
6073 block_vector + n_blocks,
6076 /* If we didn't use all of the subblocks, we've misplaced block notes. */
6077 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
6078 if (0 && last_block_vector != block_vector + n_blocks)
6081 free (block_vector);
6085 /* Subroutine of identify_blocks. Do the block substitution on the
6086 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
6088 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
6089 BLOCK_VECTOR is incremented for each block seen. */
6092 identify_blocks_1 (rtx insns, tree *block_vector, tree *end_block_vector,
6093 tree *orig_block_stack)
6096 tree *block_stack = orig_block_stack;
6098 for (insn = insns; insn; insn = NEXT_INSN (insn))
6100 if (GET_CODE (insn) == NOTE)
6102 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6106 /* If there are more block notes than BLOCKs, something
6108 if (block_vector == end_block_vector)
6111 b = *block_vector++;
6112 NOTE_BLOCK (insn) = b;
6115 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6117 /* If there are more NOTE_INSN_BLOCK_ENDs than
6118 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
6119 if (block_stack == orig_block_stack)
6122 NOTE_BLOCK (insn) = *--block_stack;
6125 else if (GET_CODE (insn) == CALL_INSN
6126 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6128 rtx cp = PATTERN (insn);
6130 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
6131 end_block_vector, block_stack);
6133 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
6134 end_block_vector, block_stack);
6136 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
6137 end_block_vector, block_stack);
6141 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
6142 something is badly wrong. */
6143 if (block_stack != orig_block_stack)
6146 return block_vector;
6149 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
6150 and create duplicate blocks. */
6151 /* ??? Need an option to either create block fragments or to create
6152 abstract origin duplicates of a source block. It really depends
6153 on what optimization has been performed. */
6156 reorder_blocks (void)
6158 tree block = DECL_INITIAL (current_function_decl);
6159 varray_type block_stack;
6161 if (block == NULL_TREE)
6164 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
6166 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
6167 reorder_blocks_0 (block);
6169 /* Prune the old trees away, so that they don't get in the way. */
6170 BLOCK_SUBBLOCKS (block) = NULL_TREE;
6171 BLOCK_CHAIN (block) = NULL_TREE;
6173 /* Recreate the block tree from the note nesting. */
6174 reorder_blocks_1 (get_insns (), block, &block_stack);
6175 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
6177 /* Remove deleted blocks from the block fragment chains. */
6178 reorder_fix_fragments (block);
6181 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
6184 reorder_blocks_0 (tree block)
6188 TREE_ASM_WRITTEN (block) = 0;
6189 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
6190 block = BLOCK_CHAIN (block);
6195 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack)
6199 for (insn = insns; insn; insn = NEXT_INSN (insn))
6201 if (GET_CODE (insn) == NOTE)
6203 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6205 tree block = NOTE_BLOCK (insn);
6207 /* If we have seen this block before, that means it now
6208 spans multiple address regions. Create a new fragment. */
6209 if (TREE_ASM_WRITTEN (block))
6211 tree new_block = copy_node (block);
6214 origin = (BLOCK_FRAGMENT_ORIGIN (block)
6215 ? BLOCK_FRAGMENT_ORIGIN (block)
6217 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
6218 BLOCK_FRAGMENT_CHAIN (new_block)
6219 = BLOCK_FRAGMENT_CHAIN (origin);
6220 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
6222 NOTE_BLOCK (insn) = new_block;
6226 BLOCK_SUBBLOCKS (block) = 0;
6227 TREE_ASM_WRITTEN (block) = 1;
6228 /* When there's only one block for the entire function,
6229 current_block == block and we mustn't do this, it
6230 will cause infinite recursion. */
6231 if (block != current_block)
6233 BLOCK_SUPERCONTEXT (block) = current_block;
6234 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6235 BLOCK_SUBBLOCKS (current_block) = block;
6236 current_block = block;
6238 VARRAY_PUSH_TREE (*p_block_stack, block);
6240 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6242 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6243 VARRAY_POP (*p_block_stack);
6244 BLOCK_SUBBLOCKS (current_block)
6245 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6246 current_block = BLOCK_SUPERCONTEXT (current_block);
6249 else if (GET_CODE (insn) == CALL_INSN
6250 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6252 rtx cp = PATTERN (insn);
6253 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
6255 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6257 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6262 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6263 appears in the block tree, select one of the fragments to become
6264 the new origin block. */
6267 reorder_fix_fragments (tree block)
6271 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6272 tree new_origin = NULL_TREE;
6276 if (! TREE_ASM_WRITTEN (dup_origin))
6278 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6280 /* Find the first of the remaining fragments. There must
6281 be at least one -- the current block. */
6282 while (! TREE_ASM_WRITTEN (new_origin))
6283 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6284 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6287 else if (! dup_origin)
6290 /* Re-root the rest of the fragments to the new origin. In the
6291 case that DUP_ORIGIN was null, that means BLOCK was the origin
6292 of a chain of fragments and we want to remove those fragments
6293 that didn't make it to the output. */
6296 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6301 if (TREE_ASM_WRITTEN (chain))
6303 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6305 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6307 chain = BLOCK_FRAGMENT_CHAIN (chain);
6312 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6313 block = BLOCK_CHAIN (block);
6317 /* Reverse the order of elements in the chain T of blocks,
6318 and return the new head of the chain (old last element). */
6321 blocks_nreverse (tree t)
6323 tree prev = 0, decl, next;
6324 for (decl = t; decl; decl = next)
6326 next = BLOCK_CHAIN (decl);
6327 BLOCK_CHAIN (decl) = prev;
6333 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6334 non-NULL, list them all into VECTOR, in a depth-first preorder
6335 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6339 all_blocks (tree block, tree *vector)
6345 TREE_ASM_WRITTEN (block) = 0;
6347 /* Record this block. */
6349 vector[n_blocks] = block;
6353 /* Record the subblocks, and their subblocks... */
6354 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6355 vector ? vector + n_blocks : 0);
6356 block = BLOCK_CHAIN (block);
6362 /* Return a vector containing all the blocks rooted at BLOCK. The
6363 number of elements in the vector is stored in N_BLOCKS_P. The
6364 vector is dynamically allocated; it is the caller's responsibility
6365 to call `free' on the pointer returned. */
6368 get_block_vector (tree block, int *n_blocks_p)
6372 *n_blocks_p = all_blocks (block, NULL);
6373 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
6374 all_blocks (block, block_vector);
6376 return block_vector;
6379 static GTY(()) int next_block_index = 2;
6381 /* Set BLOCK_NUMBER for all the blocks in FN. */
6384 number_blocks (tree fn)
6390 /* For SDB and XCOFF debugging output, we start numbering the blocks
6391 from 1 within each function, rather than keeping a running
6393 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6394 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6395 next_block_index = 1;
6398 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6400 /* The top-level BLOCK isn't numbered at all. */
6401 for (i = 1; i < n_blocks; ++i)
6402 /* We number the blocks from two. */
6403 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6405 free (block_vector);
6410 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6413 debug_find_var_in_block_tree (tree var, tree block)
6417 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6421 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6423 tree ret = debug_find_var_in_block_tree (var, t);
6431 /* Allocate a function structure for FNDECL and set its contents
6435 allocate_struct_function (tree fndecl)
6439 cfun = ggc_alloc_cleared (sizeof (struct function));
6441 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6443 cfun->stack_alignment_needed = STACK_BOUNDARY;
6444 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6446 current_function_funcdef_no = funcdef_no++;
6448 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6450 init_stmt_for_function ();
6451 init_eh_for_function ();
6453 (*lang_hooks.function.init) (cfun);
6454 if (init_machine_status)
6455 cfun->machine = (*init_machine_status) ();
6460 DECL_SAVED_INSNS (fndecl) = cfun;
6461 cfun->decl = fndecl;
6463 result = DECL_RESULT (fndecl);
6464 if (aggregate_value_p (result, fndecl))
6466 #ifdef PCC_STATIC_STRUCT_RETURN
6467 current_function_returns_pcc_struct = 1;
6469 current_function_returns_struct = 1;
6472 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
6474 current_function_needs_context
6475 = (decl_function_context (current_function_decl) != 0
6476 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6479 /* Reset cfun, and other non-struct-function variables to defaults as
6480 appropriate for emitting rtl at the start of a function. */
6483 prepare_function_start (tree fndecl)
6485 if (fndecl && DECL_SAVED_INSNS (fndecl))
6486 cfun = DECL_SAVED_INSNS (fndecl);
6488 allocate_struct_function (fndecl);
6490 init_varasm_status (cfun);
6493 cse_not_expected = ! optimize;
6495 /* Caller save not needed yet. */
6496 caller_save_needed = 0;
6498 /* We haven't done register allocation yet. */
6501 /* Indicate that we need to distinguish between the return value of the
6502 present function and the return value of a function being called. */
6503 rtx_equal_function_value_matters = 1;
6505 /* Indicate that we have not instantiated virtual registers yet. */
6506 virtuals_instantiated = 0;
6508 /* Indicate that we want CONCATs now. */
6509 generating_concat_p = 1;
6511 /* Indicate we have no need of a frame pointer yet. */
6512 frame_pointer_needed = 0;
6515 /* Initialize the rtl expansion mechanism so that we can do simple things
6516 like generate sequences. This is used to provide a context during global
6517 initialization of some passes. */
6519 init_dummy_function_start (void)
6521 prepare_function_start (NULL);
6524 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6525 and initialize static variables for generating RTL for the statements
6529 init_function_start (tree subr)
6531 prepare_function_start (subr);
6533 /* Within function body, compute a type's size as soon it is laid out. */
6534 immediate_size_expand++;
6536 /* Prevent ever trying to delete the first instruction of a
6537 function. Also tell final how to output a linenum before the
6538 function prologue. Note linenums could be missing, e.g. when
6539 compiling a Java .class file. */
6540 if (DECL_SOURCE_LINE (subr))
6541 emit_line_note (DECL_SOURCE_LOCATION (subr));
6543 /* Make sure first insn is a note even if we don't want linenums.
6544 This makes sure the first insn will never be deleted.
6545 Also, final expects a note to appear there. */
6546 emit_note (NOTE_INSN_DELETED);
6548 /* Warn if this value is an aggregate type,
6549 regardless of which calling convention we are using for it. */
6550 if (warn_aggregate_return
6551 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6552 warning ("function returns an aggregate");
6555 /* Make sure all values used by the optimization passes have sane
6558 init_function_for_compilation (void)
6562 /* No prologue/epilogue insns yet. */
6563 VARRAY_GROW (prologue, 0);
6564 VARRAY_GROW (epilogue, 0);
6565 VARRAY_GROW (sibcall_epilogue, 0);
6568 /* Expand a call to __main at the beginning of a possible main function. */
6570 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6571 #undef HAS_INIT_SECTION
6572 #define HAS_INIT_SECTION
6576 expand_main_function (void)
6578 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6579 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6581 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6585 /* Forcibly align the stack. */
6586 #ifdef STACK_GROWS_DOWNWARD
6587 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6588 stack_pointer_rtx, 1, OPTAB_WIDEN);
6590 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6591 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6592 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6593 stack_pointer_rtx, 1, OPTAB_WIDEN);
6595 if (tmp != stack_pointer_rtx)
6596 emit_move_insn (stack_pointer_rtx, tmp);
6598 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6599 tmp = force_reg (Pmode, const0_rtx);
6600 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6604 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6605 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6608 emit_insn_before (seq, tmp);
6614 #ifndef HAS_INIT_SECTION
6615 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6619 /* The PENDING_SIZES represent the sizes of variable-sized types.
6620 Create RTL for the various sizes now (using temporary variables),
6621 so that we can refer to the sizes from the RTL we are generating
6622 for the current function. The PENDING_SIZES are a TREE_LIST. The
6623 TREE_VALUE of each node is a SAVE_EXPR. */
6626 expand_pending_sizes (tree pending_sizes)
6630 /* Evaluate now the sizes of any types declared among the arguments. */
6631 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6633 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6634 /* Flush the queue in case this parameter declaration has
6640 /* Start the RTL for a new function, and set variables used for
6642 SUBR is the FUNCTION_DECL node.
6643 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6644 the function's parameters, which must be run at any return statement. */
6647 expand_function_start (tree subr, int parms_have_cleanups)
6650 rtx last_ptr = NULL_RTX;
6652 /* Make sure volatile mem refs aren't considered
6653 valid operands of arithmetic insns. */
6654 init_recog_no_volatile ();
6656 current_function_instrument_entry_exit
6657 = (flag_instrument_function_entry_exit
6658 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6660 current_function_profile
6662 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6664 current_function_limit_stack
6665 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6667 /* If function gets a static chain arg, store it in the stack frame.
6668 Do this first, so it gets the first stack slot offset. */
6669 if (current_function_needs_context)
6671 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6673 /* Delay copying static chain if it is not a register to avoid
6674 conflicts with regs used for parameters. */
6675 if (! SMALL_REGISTER_CLASSES
6676 || GET_CODE (static_chain_incoming_rtx) == REG)
6677 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6680 /* If the parameters of this function need cleaning up, get a label
6681 for the beginning of the code which executes those cleanups. This must
6682 be done before doing anything with return_label. */
6683 if (parms_have_cleanups)
6684 cleanup_label = gen_label_rtx ();
6688 /* Make the label for return statements to jump to. Do not special
6689 case machines with special return instructions -- they will be
6690 handled later during jump, ifcvt, or epilogue creation. */
6691 return_label = gen_label_rtx ();
6693 /* Initialize rtx used to return the value. */
6694 /* Do this before assign_parms so that we copy the struct value address
6695 before any library calls that assign parms might generate. */
6697 /* Decide whether to return the value in memory or in a register. */
6698 if (aggregate_value_p (DECL_RESULT (subr), subr))
6700 /* Returning something that won't go in a register. */
6701 rtx value_address = 0;
6703 #ifdef PCC_STATIC_STRUCT_RETURN
6704 if (current_function_returns_pcc_struct)
6706 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6707 value_address = assemble_static_space (size);
6712 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
6713 /* Expect to be passed the address of a place to store the value.
6714 If it is passed as an argument, assign_parms will take care of
6718 value_address = gen_reg_rtx (Pmode);
6719 emit_move_insn (value_address, sv);
6724 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6725 set_mem_attributes (x, DECL_RESULT (subr), 1);
6726 SET_DECL_RTL (DECL_RESULT (subr), x);
6729 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6730 /* If return mode is void, this decl rtl should not be used. */
6731 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6734 /* Compute the return values into a pseudo reg, which we will copy
6735 into the true return register after the cleanups are done. */
6737 /* In order to figure out what mode to use for the pseudo, we
6738 figure out what the mode of the eventual return register will
6739 actually be, and use that. */
6741 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6744 /* Structures that are returned in registers are not aggregate_value_p,
6745 so we may see a PARALLEL or a REG. */
6746 if (REG_P (hard_reg))
6747 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6748 else if (GET_CODE (hard_reg) == PARALLEL)
6749 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6753 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6754 result to the real return register(s). */
6755 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6758 /* Initialize rtx for parameters and local variables.
6759 In some cases this requires emitting insns. */
6761 assign_parms (subr);
6763 /* Copy the static chain now if it wasn't a register. The delay is to
6764 avoid conflicts with the parameter passing registers. */
6766 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6767 if (GET_CODE (static_chain_incoming_rtx) != REG)
6768 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6770 /* The following was moved from init_function_start.
6771 The move is supposed to make sdb output more accurate. */
6772 /* Indicate the beginning of the function body,
6773 as opposed to parm setup. */
6774 emit_note (NOTE_INSN_FUNCTION_BEG);
6776 if (GET_CODE (get_last_insn ()) != NOTE)
6777 emit_note (NOTE_INSN_DELETED);
6778 parm_birth_insn = get_last_insn ();
6780 context_display = 0;
6781 if (current_function_needs_context)
6783 /* Fetch static chain values for containing functions. */
6784 tem = decl_function_context (current_function_decl);
6785 /* Copy the static chain pointer into a pseudo. If we have
6786 small register classes, copy the value from memory if
6787 static_chain_incoming_rtx is a REG. */
6790 /* If the static chain originally came in a register, put it back
6791 there, then move it out in the next insn. The reason for
6792 this peculiar code is to satisfy function integration. */
6793 if (SMALL_REGISTER_CLASSES
6794 && GET_CODE (static_chain_incoming_rtx) == REG)
6795 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6796 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6801 tree rtlexp = make_node (RTL_EXPR);
6803 RTL_EXPR_RTL (rtlexp) = last_ptr;
6804 context_display = tree_cons (tem, rtlexp, context_display);
6805 tem = decl_function_context (tem);
6808 /* Chain through stack frames, assuming pointer to next lexical frame
6809 is found at the place we always store it. */
6810 #ifdef FRAME_GROWS_DOWNWARD
6811 last_ptr = plus_constant (last_ptr,
6812 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6814 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6815 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6816 last_ptr = copy_to_reg (last_ptr);
6818 /* If we are not optimizing, ensure that we know that this
6819 piece of context is live over the entire function. */
6821 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6826 if (current_function_instrument_entry_exit)
6828 rtx fun = DECL_RTL (current_function_decl);
6829 if (GET_CODE (fun) == MEM)
6830 fun = XEXP (fun, 0);
6833 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6835 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6837 hard_frame_pointer_rtx),
6841 if (current_function_profile)
6844 PROFILE_HOOK (current_function_funcdef_no);
6848 /* After the display initializations is where the tail-recursion label
6849 should go, if we end up needing one. Ensure we have a NOTE here
6850 since some things (like trampolines) get placed before this. */
6851 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
6853 /* Evaluate now the sizes of any types declared among the arguments. */
6854 expand_pending_sizes (nreverse (get_pending_sizes ()));
6856 /* Make sure there is a line number after the function entry setup code. */
6857 force_next_line_note ();
6860 /* Undo the effects of init_dummy_function_start. */
6862 expand_dummy_function_end (void)
6864 /* End any sequences that failed to be closed due to syntax errors. */
6865 while (in_sequence_p ())
6868 /* Outside function body, can't compute type's actual size
6869 until next function's body starts. */
6871 free_after_parsing (cfun);
6872 free_after_compilation (cfun);
6876 /* Call DOIT for each hard register used as a return value from
6877 the current function. */
6880 diddle_return_value (void (*doit) (rtx, void *), void *arg)
6882 rtx outgoing = current_function_return_rtx;
6887 if (GET_CODE (outgoing) == REG)
6888 (*doit) (outgoing, arg);
6889 else if (GET_CODE (outgoing) == PARALLEL)
6893 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6895 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6897 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6904 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6906 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6910 clobber_return_register (void)
6912 diddle_return_value (do_clobber_return_reg, NULL);
6914 /* In case we do use pseudo to return value, clobber it too. */
6915 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6917 tree decl_result = DECL_RESULT (current_function_decl);
6918 rtx decl_rtl = DECL_RTL (decl_result);
6919 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6921 do_clobber_return_reg (decl_rtl, NULL);
6927 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6929 emit_insn (gen_rtx_USE (VOIDmode, reg));
6933 use_return_register (void)
6935 diddle_return_value (do_use_return_reg, NULL);
6938 /* Possibly warn about unused parameters. */
6940 do_warn_unused_parameter (tree fn)
6944 for (decl = DECL_ARGUMENTS (fn);
6945 decl; decl = TREE_CHAIN (decl))
6946 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6947 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl))
6948 warning ("%Junused parameter '%D'", decl, decl);
6951 static GTY(()) rtx initial_trampoline;
6953 /* Generate RTL for the end of the current function. */
6956 expand_function_end (void)
6961 finish_expr_for_function ();
6963 /* If arg_pointer_save_area was referenced only from a nested
6964 function, we will not have initialized it yet. Do that now. */
6965 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6966 get_arg_pointer_save_area (cfun);
6968 #ifdef NON_SAVING_SETJMP
6969 /* Don't put any variables in registers if we call setjmp
6970 on a machine that fails to restore the registers. */
6971 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6973 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6974 setjmp_protect (DECL_INITIAL (current_function_decl));
6976 setjmp_protect_args ();
6980 /* Initialize any trampolines required by this function. */
6981 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6983 tree function = TREE_PURPOSE (link);
6984 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6985 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6986 #ifdef TRAMPOLINE_TEMPLATE
6991 #ifdef TRAMPOLINE_TEMPLATE
6992 /* First make sure this compilation has a template for
6993 initializing trampolines. */
6994 if (initial_trampoline == 0)
6997 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6998 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
7002 /* Generate insns to initialize the trampoline. */
7004 tramp = round_trampoline_addr (XEXP (tramp, 0));
7005 #ifdef TRAMPOLINE_TEMPLATE
7006 blktramp = replace_equiv_address (initial_trampoline, tramp);
7007 emit_block_move (blktramp, initial_trampoline,
7008 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
7010 trampolines_created = 1;
7011 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
7015 /* Put those insns at entry to the containing function (this one). */
7016 emit_insn_before (seq, tail_recursion_reentry);
7019 /* If we are doing stack checking and this function makes calls,
7020 do a stack probe at the start of the function to ensure we have enough
7021 space for another stack frame. */
7022 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
7026 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
7027 if (GET_CODE (insn) == CALL_INSN)
7030 probe_stack_range (STACK_CHECK_PROTECT,
7031 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
7034 emit_insn_before (seq, tail_recursion_reentry);
7039 /* Possibly warn about unused parameters.
7040 When frontend does unit-at-a-time, the warning is already
7041 issued at finalization time. */
7042 if (warn_unused_parameter
7043 && !lang_hooks.callgraph.expand_function)
7044 do_warn_unused_parameter (current_function_decl);
7046 /* Delete handlers for nonlocal gotos if nothing uses them. */
7047 if (nonlocal_goto_handler_slots != 0
7048 && ! current_function_has_nonlocal_label)
7051 /* End any sequences that failed to be closed due to syntax errors. */
7052 while (in_sequence_p ())
7055 /* Outside function body, can't compute type's actual size
7056 until next function's body starts. */
7057 immediate_size_expand--;
7059 clear_pending_stack_adjust ();
7060 do_pending_stack_adjust ();
7062 /* ??? This is a kludge. We want to ensure that instructions that
7063 may trap are not moved into the epilogue by scheduling, because
7064 we don't always emit unwind information for the epilogue.
7065 However, not all machine descriptions define a blockage insn, so
7066 emit an ASM_INPUT to act as one. */
7067 if (flag_non_call_exceptions)
7068 emit_insn (gen_rtx_ASM_INPUT (VOIDmode, ""));
7070 /* Mark the end of the function body.
7071 If control reaches this insn, the function can drop through
7072 without returning a value. */
7073 emit_note (NOTE_INSN_FUNCTION_END);
7075 /* Must mark the last line number note in the function, so that the test
7076 coverage code can avoid counting the last line twice. This just tells
7077 the code to ignore the immediately following line note, since there
7078 already exists a copy of this note somewhere above. This line number
7079 note is still needed for debugging though, so we can't delete it. */
7080 if (flag_test_coverage)
7081 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
7083 /* Output a linenumber for the end of the function.
7084 SDB depends on this. */
7085 force_next_line_note ();
7086 emit_line_note (input_location);
7088 /* Before the return label (if any), clobber the return
7089 registers so that they are not propagated live to the rest of
7090 the function. This can only happen with functions that drop
7091 through; if there had been a return statement, there would
7092 have either been a return rtx, or a jump to the return label.
7094 We delay actual code generation after the current_function_value_rtx
7096 clobber_after = get_last_insn ();
7098 /* Output the label for the actual return from the function,
7099 if one is expected. This happens either because a function epilogue
7100 is used instead of a return instruction, or because a return was done
7101 with a goto in order to run local cleanups, or because of pcc-style
7102 structure returning. */
7104 emit_label (return_label);
7106 if (current_function_instrument_entry_exit)
7108 rtx fun = DECL_RTL (current_function_decl);
7109 if (GET_CODE (fun) == MEM)
7110 fun = XEXP (fun, 0);
7113 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
7115 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
7117 hard_frame_pointer_rtx),
7121 /* Let except.c know where it should emit the call to unregister
7122 the function context for sjlj exceptions. */
7123 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
7124 sjlj_emit_function_exit_after (get_last_insn ());
7126 /* If we had calls to alloca, and this machine needs
7127 an accurate stack pointer to exit the function,
7128 insert some code to save and restore the stack pointer. */
7129 if (! EXIT_IGNORE_STACK
7130 && current_function_calls_alloca)
7134 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
7135 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
7138 /* If scalar return value was computed in a pseudo-reg, or was a named
7139 return value that got dumped to the stack, copy that to the hard
7141 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
7143 tree decl_result = DECL_RESULT (current_function_decl);
7144 rtx decl_rtl = DECL_RTL (decl_result);
7146 if (REG_P (decl_rtl)
7147 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
7148 : DECL_REGISTER (decl_result))
7150 rtx real_decl_rtl = current_function_return_rtx;
7152 /* This should be set in assign_parms. */
7153 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
7156 /* If this is a BLKmode structure being returned in registers,
7157 then use the mode computed in expand_return. Note that if
7158 decl_rtl is memory, then its mode may have been changed,
7159 but that current_function_return_rtx has not. */
7160 if (GET_MODE (real_decl_rtl) == BLKmode)
7161 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
7163 /* If a named return value dumped decl_return to memory, then
7164 we may need to re-do the PROMOTE_MODE signed/unsigned
7166 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
7168 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
7170 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
7171 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7174 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7176 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7178 /* If expand_function_start has created a PARALLEL for decl_rtl,
7179 move the result to the real return registers. Otherwise, do
7180 a group load from decl_rtl for a named return. */
7181 if (GET_CODE (decl_rtl) == PARALLEL)
7182 emit_group_move (real_decl_rtl, decl_rtl);
7184 emit_group_load (real_decl_rtl, decl_rtl,
7185 TREE_TYPE (decl_result),
7186 int_size_in_bytes (TREE_TYPE (decl_result)));
7189 emit_move_insn (real_decl_rtl, decl_rtl);
7193 /* If returning a structure, arrange to return the address of the value
7194 in a place where debuggers expect to find it.
7196 If returning a structure PCC style,
7197 the caller also depends on this value.
7198 And current_function_returns_pcc_struct is not necessarily set. */
7199 if (current_function_returns_struct
7200 || current_function_returns_pcc_struct)
7203 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7204 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7205 #ifdef FUNCTION_OUTGOING_VALUE
7207 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7208 current_function_decl);
7211 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7214 /* Mark this as a function return value so integrate will delete the
7215 assignment and USE below when inlining this function. */
7216 REG_FUNCTION_VALUE_P (outgoing) = 1;
7218 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7219 value_address = convert_memory_address (GET_MODE (outgoing),
7222 emit_move_insn (outgoing, value_address);
7224 /* Show return register used to hold result (in this case the address
7226 current_function_return_rtx = outgoing;
7229 /* If this is an implementation of throw, do what's necessary to
7230 communicate between __builtin_eh_return and the epilogue. */
7231 expand_eh_return ();
7233 /* Emit the actual code to clobber return register. */
7238 clobber_return_register ();
7242 after = emit_insn_after (seq, clobber_after);
7244 if (clobber_after != after)
7245 cfun->x_clobber_return_insn = after;
7248 /* Output the label for the naked return from the function, if one is
7249 expected. This is currently used only by __builtin_return. */
7250 if (naked_return_label)
7251 emit_label (naked_return_label);
7253 /* ??? This should no longer be necessary since stupid is no longer with
7254 us, but there are some parts of the compiler (eg reload_combine, and
7255 sh mach_dep_reorg) that still try and compute their own lifetime info
7256 instead of using the general framework. */
7257 use_return_register ();
7259 /* Fix up any gotos that jumped out to the outermost
7260 binding level of the function.
7261 Must follow emitting RETURN_LABEL. */
7263 /* If you have any cleanups to do at this point,
7264 and they need to create temporary variables,
7265 then you will lose. */
7266 expand_fixups (get_insns ());
7270 get_arg_pointer_save_area (struct function *f)
7272 rtx ret = f->x_arg_pointer_save_area;
7276 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7277 f->x_arg_pointer_save_area = ret;
7280 if (f == cfun && ! f->arg_pointer_save_area_init)
7284 /* Save the arg pointer at the beginning of the function. The
7285 generated stack slot may not be a valid memory address, so we
7286 have to check it and fix it if necessary. */
7288 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7292 push_topmost_sequence ();
7293 emit_insn_after (seq, get_insns ());
7294 pop_topmost_sequence ();
7300 /* Extend a vector that records the INSN_UIDs of INSNS
7301 (a list of one or more insns). */
7304 record_insns (rtx insns, varray_type *vecp)
7311 while (tmp != NULL_RTX)
7314 tmp = NEXT_INSN (tmp);
7317 i = VARRAY_SIZE (*vecp);
7318 VARRAY_GROW (*vecp, i + len);
7320 while (tmp != NULL_RTX)
7322 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7324 tmp = NEXT_INSN (tmp);
7328 /* Set the locator of the insn chain starting at INSN to LOC. */
7330 set_insn_locators (rtx insn, int loc)
7332 while (insn != NULL_RTX)
7335 INSN_LOCATOR (insn) = loc;
7336 insn = NEXT_INSN (insn);
7340 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7341 be running after reorg, SEQUENCE rtl is possible. */
7344 contains (rtx insn, varray_type vec)
7348 if (GET_CODE (insn) == INSN
7349 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7352 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7353 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7354 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7360 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7361 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7368 prologue_epilogue_contains (rtx insn)
7370 if (contains (insn, prologue))
7372 if (contains (insn, epilogue))
7378 sibcall_epilogue_contains (rtx insn)
7380 if (sibcall_epilogue)
7381 return contains (insn, sibcall_epilogue);
7386 /* Insert gen_return at the end of block BB. This also means updating
7387 block_for_insn appropriately. */
7390 emit_return_into_block (basic_block bb, rtx line_note)
7392 emit_jump_insn_after (gen_return (), BB_END (bb));
7394 emit_note_copy_after (line_note, PREV_INSN (BB_END (bb)));
7396 #endif /* HAVE_return */
7398 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7400 /* These functions convert the epilogue into a variant that does not modify the
7401 stack pointer. This is used in cases where a function returns an object
7402 whose size is not known until it is computed. The called function leaves the
7403 object on the stack, leaves the stack depressed, and returns a pointer to
7406 What we need to do is track all modifications and references to the stack
7407 pointer, deleting the modifications and changing the references to point to
7408 the location the stack pointer would have pointed to had the modifications
7411 These functions need to be portable so we need to make as few assumptions
7412 about the epilogue as we can. However, the epilogue basically contains
7413 three things: instructions to reset the stack pointer, instructions to
7414 reload registers, possibly including the frame pointer, and an
7415 instruction to return to the caller.
7417 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7418 We also make no attempt to validate the insns we make since if they are
7419 invalid, we probably can't do anything valid. The intent is that these
7420 routines get "smarter" as more and more machines start to use them and
7421 they try operating on different epilogues.
7423 We use the following structure to track what the part of the epilogue that
7424 we've already processed has done. We keep two copies of the SP equivalence,
7425 one for use during the insn we are processing and one for use in the next
7426 insn. The difference is because one part of a PARALLEL may adjust SP
7427 and the other may use it. */
7431 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7432 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7433 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7434 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7435 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7436 should be set to once we no longer need
7438 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences
7442 static void handle_epilogue_set (rtx, struct epi_info *);
7443 static void update_epilogue_consts (rtx, rtx, void *);
7444 static void emit_equiv_load (struct epi_info *);
7446 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7447 no modifications to the stack pointer. Return the new list of insns. */
7450 keep_stack_depressed (rtx insns)
7453 struct epi_info info;
7456 /* If the epilogue is just a single instruction, it must be OK as is. */
7457 if (NEXT_INSN (insns) == NULL_RTX)
7460 /* Otherwise, start a sequence, initialize the information we have, and
7461 process all the insns we were given. */
7464 info.sp_equiv_reg = stack_pointer_rtx;
7466 info.equiv_reg_src = 0;
7468 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
7469 info.const_equiv[j] = 0;
7473 while (insn != NULL_RTX)
7475 next = NEXT_INSN (insn);
7484 /* If this insn references the register that SP is equivalent to and
7485 we have a pending load to that register, we must force out the load
7486 first and then indicate we no longer know what SP's equivalent is. */
7487 if (info.equiv_reg_src != 0
7488 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7490 emit_equiv_load (&info);
7491 info.sp_equiv_reg = 0;
7494 info.new_sp_equiv_reg = info.sp_equiv_reg;
7495 info.new_sp_offset = info.sp_offset;
7497 /* If this is a (RETURN) and the return address is on the stack,
7498 update the address and change to an indirect jump. */
7499 if (GET_CODE (PATTERN (insn)) == RETURN
7500 || (GET_CODE (PATTERN (insn)) == PARALLEL
7501 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7503 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7505 HOST_WIDE_INT offset = 0;
7506 rtx jump_insn, jump_set;
7508 /* If the return address is in a register, we can emit the insn
7509 unchanged. Otherwise, it must be a MEM and we see what the
7510 base register and offset are. In any case, we have to emit any
7511 pending load to the equivalent reg of SP, if any. */
7512 if (GET_CODE (retaddr) == REG)
7514 emit_equiv_load (&info);
7519 else if (GET_CODE (retaddr) == MEM
7520 && GET_CODE (XEXP (retaddr, 0)) == REG)
7521 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7522 else if (GET_CODE (retaddr) == MEM
7523 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7524 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7525 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7527 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7528 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7533 /* If the base of the location containing the return pointer
7534 is SP, we must update it with the replacement address. Otherwise,
7535 just build the necessary MEM. */
7536 retaddr = plus_constant (base, offset);
7537 if (base == stack_pointer_rtx)
7538 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7539 plus_constant (info.sp_equiv_reg,
7542 retaddr = gen_rtx_MEM (Pmode, retaddr);
7544 /* If there is a pending load to the equivalent register for SP
7545 and we reference that register, we must load our address into
7546 a scratch register and then do that load. */
7547 if (info.equiv_reg_src
7548 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7553 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7554 if (HARD_REGNO_MODE_OK (regno, Pmode)
7555 && !fixed_regs[regno]
7556 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7557 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7559 && !refers_to_regno_p (regno,
7560 regno + HARD_REGNO_NREGS (regno,
7562 info.equiv_reg_src, NULL)
7563 && info.const_equiv[regno] == 0)
7566 if (regno == FIRST_PSEUDO_REGISTER)
7569 reg = gen_rtx_REG (Pmode, regno);
7570 emit_move_insn (reg, retaddr);
7574 emit_equiv_load (&info);
7575 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7577 /* Show the SET in the above insn is a RETURN. */
7578 jump_set = single_set (jump_insn);
7582 SET_IS_RETURN_P (jump_set) = 1;
7585 /* If SP is not mentioned in the pattern and its equivalent register, if
7586 any, is not modified, just emit it. Otherwise, if neither is set,
7587 replace the reference to SP and emit the insn. If none of those are
7588 true, handle each SET individually. */
7589 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7590 && (info.sp_equiv_reg == stack_pointer_rtx
7591 || !reg_set_p (info.sp_equiv_reg, insn)))
7593 else if (! reg_set_p (stack_pointer_rtx, insn)
7594 && (info.sp_equiv_reg == stack_pointer_rtx
7595 || !reg_set_p (info.sp_equiv_reg, insn)))
7597 if (! validate_replace_rtx (stack_pointer_rtx,
7598 plus_constant (info.sp_equiv_reg,
7605 else if (GET_CODE (PATTERN (insn)) == SET)
7606 handle_epilogue_set (PATTERN (insn), &info);
7607 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7609 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7610 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7611 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7616 info.sp_equiv_reg = info.new_sp_equiv_reg;
7617 info.sp_offset = info.new_sp_offset;
7619 /* Now update any constants this insn sets. */
7620 note_stores (PATTERN (insn), update_epilogue_consts, &info);
7624 insns = get_insns ();
7629 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7630 structure that contains information about what we've seen so far. We
7631 process this SET by either updating that data or by emitting one or
7635 handle_epilogue_set (rtx set, struct epi_info *p)
7637 /* First handle the case where we are setting SP. Record what it is being
7638 set from. If unknown, abort. */
7639 if (reg_set_p (stack_pointer_rtx, set))
7641 if (SET_DEST (set) != stack_pointer_rtx)
7644 if (GET_CODE (SET_SRC (set)) == PLUS)
7646 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7647 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7648 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7649 else if (GET_CODE (XEXP (SET_SRC (set), 1)) == REG
7650 && REGNO (XEXP (SET_SRC (set), 1)) < FIRST_PSEUDO_REGISTER
7651 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))] != 0)
7653 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
7658 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7660 /* If we are adjusting SP, we adjust from the old data. */
7661 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7663 p->new_sp_equiv_reg = p->sp_equiv_reg;
7664 p->new_sp_offset += p->sp_offset;
7667 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7673 /* Next handle the case where we are setting SP's equivalent register.
7674 If we already have a value to set it to, abort. We could update, but
7675 there seems little point in handling that case. Note that we have
7676 to allow for the case where we are setting the register set in
7677 the previous part of a PARALLEL inside a single insn. But use the
7678 old offset for any updates within this insn. We must allow for the case
7679 where the register is being set in a different (usually wider) mode than
7681 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7683 if (p->equiv_reg_src != 0
7684 || GET_CODE (p->new_sp_equiv_reg) != REG
7685 || GET_CODE (SET_DEST (set)) != REG
7686 || GET_MODE_BITSIZE (GET_MODE (SET_DEST (set))) > BITS_PER_WORD
7687 || REGNO (p->new_sp_equiv_reg) != REGNO (SET_DEST (set)))
7691 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7692 plus_constant (p->sp_equiv_reg,
7696 /* Otherwise, replace any references to SP in the insn to its new value
7697 and emit the insn. */
7700 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7701 plus_constant (p->sp_equiv_reg,
7703 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7704 plus_constant (p->sp_equiv_reg,
7710 /* Update the tracking information for registers set to constants. */
7713 update_epilogue_consts (rtx dest, rtx x, void *data)
7715 struct epi_info *p = (struct epi_info *) data;
7717 if (GET_CODE (dest) != REG || REGNO (dest) >= FIRST_PSEUDO_REGISTER)
7719 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x))
7720 || GET_CODE (SET_SRC (x)) != CONST_INT)
7721 p->const_equiv[REGNO (dest)] = 0;
7723 p->const_equiv[REGNO (dest)] = SET_SRC (x);
7726 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7729 emit_equiv_load (struct epi_info *p)
7731 if (p->equiv_reg_src != 0)
7733 rtx dest = p->sp_equiv_reg;
7735 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest))
7736 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src),
7737 REGNO (p->sp_equiv_reg));
7739 emit_move_insn (dest, p->equiv_reg_src);
7740 p->equiv_reg_src = 0;
7745 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7746 this into place with notes indicating where the prologue ends and where
7747 the epilogue begins. Update the basic block information when possible. */
7750 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
7754 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7757 #ifdef HAVE_prologue
7758 rtx prologue_end = NULL_RTX;
7760 #if defined (HAVE_epilogue) || defined(HAVE_return)
7761 rtx epilogue_end = NULL_RTX;
7764 #ifdef HAVE_prologue
7768 seq = gen_prologue ();
7771 /* Retain a map of the prologue insns. */
7772 record_insns (seq, &prologue);
7773 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
7777 set_insn_locators (seq, prologue_locator);
7779 /* Can't deal with multiple successors of the entry block
7780 at the moment. Function should always have at least one
7782 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7785 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7790 /* If the exit block has no non-fake predecessors, we don't need
7792 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7793 if ((e->flags & EDGE_FAKE) == 0)
7799 if (optimize && HAVE_return)
7801 /* If we're allowed to generate a simple return instruction,
7802 then by definition we don't need a full epilogue. Examine
7803 the block that falls through to EXIT. If it does not
7804 contain any code, examine its predecessors and try to
7805 emit (conditional) return instructions. */
7811 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7812 if (e->flags & EDGE_FALLTHRU)
7818 /* Verify that there are no active instructions in the last block. */
7819 label = BB_END (last);
7820 while (label && GET_CODE (label) != CODE_LABEL)
7822 if (active_insn_p (label))
7824 label = PREV_INSN (label);
7827 if (BB_HEAD (last) == label && GET_CODE (label) == CODE_LABEL)
7829 rtx epilogue_line_note = NULL_RTX;
7831 /* Locate the line number associated with the closing brace,
7832 if we can find one. */
7833 for (seq = get_last_insn ();
7834 seq && ! active_insn_p (seq);
7835 seq = PREV_INSN (seq))
7836 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7838 epilogue_line_note = seq;
7842 for (e = last->pred; e; e = e_next)
7844 basic_block bb = e->src;
7847 e_next = e->pred_next;
7848 if (bb == ENTRY_BLOCK_PTR)
7852 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7855 /* If we have an unconditional jump, we can replace that
7856 with a simple return instruction. */
7857 if (simplejump_p (jump))
7859 emit_return_into_block (bb, epilogue_line_note);
7863 /* If we have a conditional jump, we can try to replace
7864 that with a conditional return instruction. */
7865 else if (condjump_p (jump))
7867 if (! redirect_jump (jump, 0, 0))
7870 /* If this block has only one successor, it both jumps
7871 and falls through to the fallthru block, so we can't
7873 if (bb->succ->succ_next == NULL)
7879 /* Fix up the CFG for the successful change we just made. */
7880 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7883 /* Emit a return insn for the exit fallthru block. Whether
7884 this is still reachable will be determined later. */
7886 emit_barrier_after (BB_END (last));
7887 emit_return_into_block (last, epilogue_line_note);
7888 epilogue_end = BB_END (last);
7889 last->succ->flags &= ~EDGE_FALLTHRU;
7894 #ifdef HAVE_epilogue
7897 /* Find the edge that falls through to EXIT. Other edges may exist
7898 due to RETURN instructions, but those don't need epilogues.
7899 There really shouldn't be a mixture -- either all should have
7900 been converted or none, however... */
7902 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7903 if (e->flags & EDGE_FALLTHRU)
7909 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
7911 seq = gen_epilogue ();
7913 #ifdef INCOMING_RETURN_ADDR_RTX
7914 /* If this function returns with the stack depressed and we can support
7915 it, massage the epilogue to actually do that. */
7916 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7917 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7918 seq = keep_stack_depressed (seq);
7921 emit_jump_insn (seq);
7923 /* Retain a map of the epilogue insns. */
7924 record_insns (seq, &epilogue);
7925 set_insn_locators (seq, epilogue_locator);
7930 insert_insn_on_edge (seq, e);
7937 commit_edge_insertions ();
7939 #ifdef HAVE_sibcall_epilogue
7940 /* Emit sibling epilogues before any sibling call sites. */
7941 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7943 basic_block bb = e->src;
7944 rtx insn = BB_END (bb);
7948 if (GET_CODE (insn) != CALL_INSN
7949 || ! SIBLING_CALL_P (insn))
7953 emit_insn (gen_sibcall_epilogue ());
7957 /* Retain a map of the epilogue insns. Used in life analysis to
7958 avoid getting rid of sibcall epilogue insns. Do this before we
7959 actually emit the sequence. */
7960 record_insns (seq, &sibcall_epilogue);
7961 set_insn_locators (seq, epilogue_locator);
7963 i = PREV_INSN (insn);
7964 newinsn = emit_insn_before (seq, insn);
7968 #ifdef HAVE_prologue
7969 /* This is probably all useless now that we use locators. */
7974 /* GDB handles `break f' by setting a breakpoint on the first
7975 line note after the prologue. Which means (1) that if
7976 there are line number notes before where we inserted the
7977 prologue we should move them, and (2) we should generate a
7978 note before the end of the first basic block, if there isn't
7981 ??? This behavior is completely broken when dealing with
7982 multiple entry functions. We simply place the note always
7983 into first basic block and let alternate entry points
7987 for (insn = prologue_end; insn; insn = prev)
7989 prev = PREV_INSN (insn);
7990 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7992 /* Note that we cannot reorder the first insn in the
7993 chain, since rest_of_compilation relies on that
7994 remaining constant. */
7997 reorder_insns (insn, insn, prologue_end);
8001 /* Find the last line number note in the first block. */
8002 for (insn = BB_END (ENTRY_BLOCK_PTR->next_bb);
8003 insn != prologue_end && insn;
8004 insn = PREV_INSN (insn))
8005 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
8008 /* If we didn't find one, make a copy of the first line number
8012 for (insn = next_active_insn (prologue_end);
8014 insn = PREV_INSN (insn))
8015 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
8017 emit_note_copy_after (insn, prologue_end);
8023 #ifdef HAVE_epilogue
8028 /* Similarly, move any line notes that appear after the epilogue.
8029 There is no need, however, to be quite so anal about the existence
8030 of such a note. Also move the NOTE_INSN_FUNCTION_END and (possibly)
8031 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
8033 for (insn = epilogue_end; insn; insn = next)
8035 next = NEXT_INSN (insn);
8036 if (GET_CODE (insn) == NOTE
8037 && (NOTE_LINE_NUMBER (insn) > 0
8038 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG
8039 || NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_END))
8040 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
8046 /* Reposition the prologue-end and epilogue-begin notes after instruction
8047 scheduling and delayed branch scheduling. */
8050 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
8052 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
8053 rtx insn, last, note;
8056 if ((len = VARRAY_SIZE (prologue)) > 0)
8060 /* Scan from the beginning until we reach the last prologue insn.
8061 We apparently can't depend on basic_block_{head,end} after
8063 for (insn = f; insn; insn = NEXT_INSN (insn))
8065 if (GET_CODE (insn) == NOTE)
8067 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
8070 else if (contains (insn, prologue))
8080 /* Find the prologue-end note if we haven't already, and
8081 move it to just after the last prologue insn. */
8084 for (note = last; (note = NEXT_INSN (note));)
8085 if (GET_CODE (note) == NOTE
8086 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
8090 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
8091 if (GET_CODE (last) == CODE_LABEL)
8092 last = NEXT_INSN (last);
8093 reorder_insns (note, note, last);
8097 if ((len = VARRAY_SIZE (epilogue)) > 0)
8101 /* Scan from the end until we reach the first epilogue insn.
8102 We apparently can't depend on basic_block_{head,end} after
8104 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
8106 if (GET_CODE (insn) == NOTE)
8108 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
8111 else if (contains (insn, epilogue))
8121 /* Find the epilogue-begin note if we haven't already, and
8122 move it to just before the first epilogue insn. */
8125 for (note = insn; (note = PREV_INSN (note));)
8126 if (GET_CODE (note) == NOTE
8127 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
8131 if (PREV_INSN (last) != note)
8132 reorder_insns (note, note, PREV_INSN (last));
8135 #endif /* HAVE_prologue or HAVE_epilogue */
8138 /* Called once, at initialization, to initialize function.c. */
8141 init_function_once (void)
8143 VARRAY_INT_INIT (prologue, 0, "prologue");
8144 VARRAY_INT_INIT (epilogue, 0, "epilogue");
8145 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
8148 /* Returns the name of the current function. */
8150 current_function_name (void)
8152 return (*lang_hooks.decl_printable_name) (cfun->decl, 2);
8155 #include "gt-function.h"