1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
43 #include "coretypes.h"
54 #include "hard-reg-set.h"
55 #include "insn-config.h"
58 #include "basic-block.h"
63 #include "integrate.h"
64 #include "langhooks.h"
67 #ifndef TRAMPOLINE_ALIGNMENT
68 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
71 #ifndef LOCAL_ALIGNMENT
72 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
75 #ifndef STACK_ALIGNMENT_NEEDED
76 #define STACK_ALIGNMENT_NEEDED 1
79 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
81 /* Some systems use __main in a way incompatible with its use in gcc, in these
82 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
83 give the same symbol without quotes for an alternative entry point. You
84 must define both, or neither. */
86 #define NAME__MAIN "__main"
89 /* Round a value to the lowest integer less than it that is a multiple of
90 the required alignment. Avoid using division in case the value is
91 negative. Assume the alignment is a power of two. */
92 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
94 /* Similar, but round to the next highest integer that meets the
96 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
98 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
99 during rtl generation. If they are different register numbers, this is
100 always true. It may also be true if
101 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
102 generation. See fix_lexical_addr for details. */
104 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
105 #define NEED_SEPARATE_AP
108 /* Nonzero if function being compiled doesn't contain any calls
109 (ignoring the prologue and epilogue). This is set prior to
110 local register allocation and is valid for the remaining
112 int current_function_is_leaf;
114 /* Nonzero if function being compiled doesn't contain any instructions
115 that can throw an exception. This is set prior to final. */
117 int current_function_nothrow;
119 /* Nonzero if function being compiled doesn't modify the stack pointer
120 (ignoring the prologue and epilogue). This is only valid after
121 life_analysis has run. */
122 int current_function_sp_is_unchanging;
124 /* Nonzero if the function being compiled is a leaf function which only
125 uses leaf registers. This is valid after reload (specifically after
126 sched2) and is useful only if the port defines LEAF_REGISTERS. */
127 int current_function_uses_only_leaf_regs;
129 /* Nonzero once virtual register instantiation has been done.
130 assign_stack_local uses frame_pointer_rtx when this is nonzero.
131 calls.c:emit_library_call_value_1 uses it to set up
132 post-instantiation libcalls. */
133 int virtuals_instantiated;
135 /* Nonzero if at least one trampoline has been created. */
136 int trampolines_created;
138 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
139 static GTY(()) int funcdef_no;
141 /* These variables hold pointers to functions to create and destroy
142 target specific, per-function data structures. */
143 struct machine_function * (*init_machine_status) (void);
145 /* The FUNCTION_DECL for an inline function currently being expanded. */
146 tree inline_function_decl;
148 /* The currently compiled function. */
149 struct function *cfun = 0;
151 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
152 static GTY(()) varray_type prologue;
153 static GTY(()) varray_type epilogue;
155 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
157 static GTY(()) varray_type sibcall_epilogue;
159 /* In order to evaluate some expressions, such as function calls returning
160 structures in memory, we need to temporarily allocate stack locations.
161 We record each allocated temporary in the following structure.
163 Associated with each temporary slot is a nesting level. When we pop up
164 one level, all temporaries associated with the previous level are freed.
165 Normally, all temporaries are freed after the execution of the statement
166 in which they were created. However, if we are inside a ({...}) grouping,
167 the result may be in a temporary and hence must be preserved. If the
168 result could be in a temporary, we preserve it if we can determine which
169 one it is in. If we cannot determine which temporary may contain the
170 result, all temporaries are preserved. A temporary is preserved by
171 pretending it was allocated at the previous nesting level.
173 Automatic variables are also assigned temporary slots, at the nesting
174 level where they are defined. They are marked a "kept" so that
175 free_temp_slots will not free them. */
177 struct temp_slot GTY(())
179 /* Points to next temporary slot. */
180 struct temp_slot *next;
181 /* The rtx to used to reference the slot. */
183 /* The rtx used to represent the address if not the address of the
184 slot above. May be an EXPR_LIST if multiple addresses exist. */
186 /* The alignment (in bits) of the slot. */
188 /* The size, in units, of the slot. */
190 /* The type of the object in the slot, or zero if it doesn't correspond
191 to a type. We use this to determine whether a slot can be reused.
192 It can be reused if objects of the type of the new slot will always
193 conflict with objects of the type of the old slot. */
195 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
197 /* Nonzero if this temporary is currently in use. */
199 /* Nonzero if this temporary has its address taken. */
201 /* Nesting level at which this slot is being used. */
203 /* Nonzero if this should survive a call to free_temp_slots. */
205 /* The offset of the slot from the frame_pointer, including extra space
206 for alignment. This info is for combine_temp_slots. */
207 HOST_WIDE_INT base_offset;
208 /* The size of the slot, including extra space for alignment. This
209 info is for combine_temp_slots. */
210 HOST_WIDE_INT full_size;
213 /* This structure is used to record MEMs or pseudos used to replace VAR, any
214 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
215 maintain this list in case two operands of an insn were required to match;
216 in that case we must ensure we use the same replacement. */
218 struct fixup_replacement GTY(())
222 struct fixup_replacement *next;
225 struct insns_for_mem_entry
229 /* These are the INSNs which reference the MEM. */
233 /* Forward declarations. */
235 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int,
237 static struct temp_slot *find_temp_slot_from_address (rtx);
238 static void put_reg_into_stack (struct function *, rtx, tree, enum machine_mode,
239 enum machine_mode, int, unsigned int, int, htab_t);
240 static void schedule_fixup_var_refs (struct function *, rtx, tree, enum machine_mode,
242 static void fixup_var_refs (rtx, enum machine_mode, int, rtx, htab_t);
243 static struct fixup_replacement
244 *find_fixup_replacement (struct fixup_replacement **, rtx);
245 static void fixup_var_refs_insns (rtx, rtx, enum machine_mode, int, int, rtx);
246 static void fixup_var_refs_insns_with_hash (htab_t, rtx, enum machine_mode, int, rtx);
247 static void fixup_var_refs_insn (rtx, rtx, enum machine_mode, int, int, rtx);
248 static void fixup_var_refs_1 (rtx, enum machine_mode, rtx *, rtx,
249 struct fixup_replacement **, rtx);
250 static rtx fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
251 static rtx walk_fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
252 static rtx fixup_stack_1 (rtx, rtx);
253 static void optimize_bit_field (rtx, rtx, rtx *);
254 static void instantiate_decls (tree, int);
255 static void instantiate_decls_1 (tree, int);
256 static void instantiate_decl (rtx, HOST_WIDE_INT, int);
257 static rtx instantiate_new_reg (rtx, HOST_WIDE_INT *);
258 static int instantiate_virtual_regs_1 (rtx *, rtx, int);
259 static void delete_handlers (void);
260 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
261 static void pad_below (struct args_size *, enum machine_mode, tree);
262 static rtx round_trampoline_addr (rtx);
263 static rtx adjust_trampoline_addr (rtx);
264 static tree *identify_blocks_1 (rtx, tree *, tree *, tree *);
265 static void reorder_blocks_0 (tree);
266 static void reorder_blocks_1 (rtx, tree, varray_type *);
267 static void reorder_fix_fragments (tree);
268 static tree blocks_nreverse (tree);
269 static int all_blocks (tree, tree *);
270 static tree *get_block_vector (tree, int *);
271 extern tree debug_find_var_in_block_tree (tree, tree);
272 /* We always define `record_insns' even if 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 static GTY(()) 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->computed_goto_common_label = NULL;
456 f->computed_goto_common_reg = NULL;
457 f->x_save_expr_regs = NULL;
458 f->x_stack_slot_list = NULL;
459 f->x_rtl_expr_chain = NULL;
460 f->x_tail_recursion_label = NULL;
461 f->x_tail_recursion_reentry = NULL;
462 f->x_arg_pointer_save_area = NULL;
463 f->x_clobber_return_insn = NULL;
464 f->x_context_display = NULL;
465 f->x_trampoline_list = NULL;
466 f->x_parm_birth_insn = NULL;
467 f->x_last_parm_insn = NULL;
468 f->x_parm_reg_stack_loc = NULL;
469 f->fixup_var_refs_queue = NULL;
470 f->original_arg_vector = NULL;
471 f->original_decl_initial = NULL;
472 f->inl_last_parm_insn = NULL;
473 f->epilogue_delay_list = NULL;
476 /* Allocate fixed slots in the stack frame of the current function. */
478 /* Return size needed for stack frame based on slots so far allocated in
480 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
481 the caller may have to do that. */
484 get_func_frame_size (struct function *f)
486 #ifdef FRAME_GROWS_DOWNWARD
487 return -f->x_frame_offset;
489 return f->x_frame_offset;
493 /* Return size needed for stack frame based on slots so far allocated.
494 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
495 the caller may have to do that. */
497 get_frame_size (void)
499 return get_func_frame_size (cfun);
502 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
503 with machine mode MODE.
505 ALIGN controls the amount of alignment for the address of the slot:
506 0 means according to MODE,
507 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
508 positive specifies alignment boundary in bits.
510 We do not round to stack_boundary here.
512 FUNCTION specifies the function to allocate in. */
515 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
516 struct function *function)
519 int bigend_correction = 0;
521 int frame_off, frame_alignment, frame_phase;
528 alignment = BIGGEST_ALIGNMENT;
530 alignment = GET_MODE_ALIGNMENT (mode);
532 /* Allow the target to (possibly) increase the alignment of this
534 type = (*lang_hooks.types.type_for_mode) (mode, 0);
536 alignment = LOCAL_ALIGNMENT (type, alignment);
538 alignment /= BITS_PER_UNIT;
540 else if (align == -1)
542 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
543 size = CEIL_ROUND (size, alignment);
546 alignment = align / BITS_PER_UNIT;
548 #ifdef FRAME_GROWS_DOWNWARD
549 function->x_frame_offset -= size;
552 /* Ignore alignment we can't do with expected alignment of the boundary. */
553 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
554 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
556 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
557 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
559 /* Calculate how many bytes the start of local variables is off from
561 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
562 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
563 frame_phase = frame_off ? frame_alignment - frame_off : 0;
565 /* Round the frame offset to the specified alignment. The default is
566 to always honor requests to align the stack but a port may choose to
567 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
568 if (STACK_ALIGNMENT_NEEDED
572 /* We must be careful here, since FRAME_OFFSET might be negative and
573 division with a negative dividend isn't as well defined as we might
574 like. So we instead assume that ALIGNMENT is a power of two and
575 use logical operations which are unambiguous. */
576 #ifdef FRAME_GROWS_DOWNWARD
577 function->x_frame_offset
578 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
581 function->x_frame_offset
582 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
587 /* On a big-endian machine, if we are allocating more space than we will use,
588 use the least significant bytes of those that are allocated. */
589 if (BYTES_BIG_ENDIAN && mode != BLKmode)
590 bigend_correction = size - GET_MODE_SIZE (mode);
592 /* If we have already instantiated virtual registers, return the actual
593 address relative to the frame pointer. */
594 if (function == cfun && virtuals_instantiated)
595 addr = plus_constant (frame_pointer_rtx,
597 (frame_offset + bigend_correction
598 + STARTING_FRAME_OFFSET, Pmode));
600 addr = plus_constant (virtual_stack_vars_rtx,
602 (function->x_frame_offset + bigend_correction,
605 #ifndef FRAME_GROWS_DOWNWARD
606 function->x_frame_offset += size;
609 x = gen_rtx_MEM (mode, addr);
611 function->x_stack_slot_list
612 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
617 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
621 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
623 return assign_stack_local_1 (mode, size, align, cfun);
626 /* Allocate a temporary stack slot and record it for possible later
629 MODE is the machine mode to be given to the returned rtx.
631 SIZE is the size in units of the space required. We do no rounding here
632 since assign_stack_local will do any required rounding.
634 KEEP is 1 if this slot is to be retained after a call to
635 free_temp_slots. Automatic variables for a block are allocated
636 with this flag. KEEP is 2 if we allocate a longer term temporary,
637 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
638 if we are to allocate something at an inner level to be treated as
639 a variable in the block (e.g., a SAVE_EXPR).
641 TYPE is the type that will be used for the stack slot. */
644 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, int keep,
648 struct temp_slot *p, *best_p = 0;
651 /* If SIZE is -1 it means that somebody tried to allocate a temporary
652 of a variable size. */
657 align = BIGGEST_ALIGNMENT;
659 align = GET_MODE_ALIGNMENT (mode);
662 type = (*lang_hooks.types.type_for_mode) (mode, 0);
665 align = LOCAL_ALIGNMENT (type, align);
667 /* Try to find an available, already-allocated temporary of the proper
668 mode which meets the size and alignment requirements. Choose the
669 smallest one with the closest alignment. */
670 for (p = temp_slots; p; p = p->next)
671 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
673 && objects_must_conflict_p (p->type, type)
674 && (best_p == 0 || best_p->size > p->size
675 || (best_p->size == p->size && best_p->align > p->align)))
677 if (p->align == align && p->size == size)
685 /* Make our best, if any, the one to use. */
688 /* If there are enough aligned bytes left over, make them into a new
689 temp_slot so that the extra bytes don't get wasted. Do this only
690 for BLKmode slots, so that we can be sure of the alignment. */
691 if (GET_MODE (best_p->slot) == BLKmode)
693 int alignment = best_p->align / BITS_PER_UNIT;
694 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
696 if (best_p->size - rounded_size >= alignment)
698 p = ggc_alloc (sizeof (struct temp_slot));
699 p->in_use = p->addr_taken = 0;
700 p->size = best_p->size - rounded_size;
701 p->base_offset = best_p->base_offset + rounded_size;
702 p->full_size = best_p->full_size - rounded_size;
703 p->slot = gen_rtx_MEM (BLKmode,
704 plus_constant (XEXP (best_p->slot, 0),
706 p->align = best_p->align;
709 p->type = best_p->type;
710 p->next = temp_slots;
713 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
716 best_p->size = rounded_size;
717 best_p->full_size = rounded_size;
724 /* If we still didn't find one, make a new temporary. */
727 HOST_WIDE_INT frame_offset_old = frame_offset;
729 p = ggc_alloc (sizeof (struct temp_slot));
731 /* We are passing an explicit alignment request to assign_stack_local.
732 One side effect of that is assign_stack_local will not round SIZE
733 to ensure the frame offset remains suitably aligned.
735 So for requests which depended on the rounding of SIZE, we go ahead
736 and round it now. We also make sure ALIGNMENT is at least
737 BIGGEST_ALIGNMENT. */
738 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
740 p->slot = assign_stack_local (mode,
742 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
748 /* The following slot size computation is necessary because we don't
749 know the actual size of the temporary slot until assign_stack_local
750 has performed all the frame alignment and size rounding for the
751 requested temporary. Note that extra space added for alignment
752 can be either above or below this stack slot depending on which
753 way the frame grows. We include the extra space if and only if it
754 is above this slot. */
755 #ifdef FRAME_GROWS_DOWNWARD
756 p->size = frame_offset_old - frame_offset;
761 /* Now define the fields used by combine_temp_slots. */
762 #ifdef FRAME_GROWS_DOWNWARD
763 p->base_offset = frame_offset;
764 p->full_size = frame_offset_old - frame_offset;
766 p->base_offset = frame_offset_old;
767 p->full_size = frame_offset - frame_offset_old;
770 p->next = temp_slots;
776 p->rtl_expr = seq_rtl_expr;
781 p->level = target_temp_slot_level;
786 p->level = var_temp_slot_level;
791 p->level = temp_slot_level;
796 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
797 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
798 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
800 /* If we know the alias set for the memory that will be used, use
801 it. If there's no TYPE, then we don't know anything about the
802 alias set for the memory. */
803 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
804 set_mem_align (slot, align);
806 /* If a type is specified, set the relevant flags. */
809 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
810 && TYPE_READONLY (type));
811 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
812 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
818 /* Allocate a temporary stack slot and record it for possible later
819 reuse. First three arguments are same as in preceding function. */
822 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
824 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
827 /* Assign a temporary.
828 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
829 and so that should be used in error messages. In either case, we
830 allocate of the given type.
831 KEEP is as for assign_stack_temp.
832 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
833 it is 0 if a register is OK.
834 DONT_PROMOTE is 1 if we should not promote values in register
838 assign_temp (tree type_or_decl, int keep, int memory_required,
839 int dont_promote ATTRIBUTE_UNUSED)
842 enum machine_mode mode;
843 #ifndef PROMOTE_FOR_CALL_ONLY
847 if (DECL_P (type_or_decl))
848 decl = type_or_decl, type = TREE_TYPE (decl);
850 decl = NULL, type = type_or_decl;
852 mode = TYPE_MODE (type);
853 #ifndef PROMOTE_FOR_CALL_ONLY
854 unsignedp = TREE_UNSIGNED (type);
857 if (mode == BLKmode || memory_required)
859 HOST_WIDE_INT size = int_size_in_bytes (type);
862 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
863 problems with allocating the stack space. */
867 /* Unfortunately, we don't yet know how to allocate variable-sized
868 temporaries. However, sometimes we have a fixed upper limit on
869 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
870 instead. This is the case for Chill variable-sized strings. */
871 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
872 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
873 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
874 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
876 /* The size of the temporary may be too large to fit into an integer. */
877 /* ??? Not sure this should happen except for user silliness, so limit
878 this to things that aren't compiler-generated temporaries. The
879 rest of the time we'll abort in assign_stack_temp_for_type. */
880 if (decl && size == -1
881 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
883 error ("%Jsize of variable '%D' is too large", decl, decl);
887 tmp = assign_stack_temp_for_type (mode, size, keep, type);
891 #ifndef PROMOTE_FOR_CALL_ONLY
893 mode = promote_mode (type, mode, &unsignedp, 0);
896 return gen_reg_rtx (mode);
899 /* Combine temporary stack slots which are adjacent on the stack.
901 This allows for better use of already allocated stack space. This is only
902 done for BLKmode slots because we can be sure that we won't have alignment
903 problems in this case. */
906 combine_temp_slots (void)
908 struct temp_slot *p, *q;
909 struct temp_slot *prev_p, *prev_q;
912 /* We can't combine slots, because the information about which slot
913 is in which alias set will be lost. */
914 if (flag_strict_aliasing)
917 /* If there are a lot of temp slots, don't do anything unless
918 high levels of optimization. */
919 if (! flag_expensive_optimizations)
920 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
921 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
924 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
928 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
929 for (q = p->next, prev_q = p; q; q = prev_q->next)
932 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
934 if (p->base_offset + p->full_size == q->base_offset)
936 /* Q comes after P; combine Q into P. */
938 p->full_size += q->full_size;
941 else if (q->base_offset + q->full_size == p->base_offset)
943 /* P comes after Q; combine P into Q. */
945 q->full_size += p->full_size;
950 /* Either delete Q or advance past it. */
952 prev_q->next = q->next;
956 /* Either delete P or advance past it. */
960 prev_p->next = p->next;
962 temp_slots = p->next;
969 /* Find the temp slot corresponding to the object at address X. */
971 static struct temp_slot *
972 find_temp_slot_from_address (rtx x)
977 for (p = temp_slots; p; p = p->next)
982 else if (XEXP (p->slot, 0) == x
984 || (GET_CODE (x) == PLUS
985 && XEXP (x, 0) == virtual_stack_vars_rtx
986 && GET_CODE (XEXP (x, 1)) == CONST_INT
987 && INTVAL (XEXP (x, 1)) >= p->base_offset
988 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
991 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
992 for (next = p->address; next; next = XEXP (next, 1))
993 if (XEXP (next, 0) == x)
997 /* If we have a sum involving a register, see if it points to a temp
999 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1000 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1002 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1003 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1009 /* Indicate that NEW is an alternate way of referring to the temp slot
1010 that previously was known by OLD. */
1013 update_temp_slot_address (rtx old, rtx new)
1015 struct temp_slot *p;
1017 if (rtx_equal_p (old, new))
1020 p = find_temp_slot_from_address (old);
1022 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1023 is a register, see if one operand of the PLUS is a temporary
1024 location. If so, NEW points into it. Otherwise, if both OLD and
1025 NEW are a PLUS and if there is a register in common between them.
1026 If so, try a recursive call on those values. */
1029 if (GET_CODE (old) != PLUS)
1032 if (GET_CODE (new) == REG)
1034 update_temp_slot_address (XEXP (old, 0), new);
1035 update_temp_slot_address (XEXP (old, 1), new);
1038 else if (GET_CODE (new) != PLUS)
1041 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1042 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1043 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1044 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1045 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1046 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1047 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1048 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1053 /* Otherwise add an alias for the temp's address. */
1054 else if (p->address == 0)
1058 if (GET_CODE (p->address) != EXPR_LIST)
1059 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1061 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1065 /* If X could be a reference to a temporary slot, mark the fact that its
1066 address was taken. */
1069 mark_temp_addr_taken (rtx x)
1071 struct temp_slot *p;
1076 /* If X is not in memory or is at a constant address, it cannot be in
1077 a temporary slot. */
1078 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1081 p = find_temp_slot_from_address (XEXP (x, 0));
1086 /* If X could be a reference to a temporary slot, mark that slot as
1087 belonging to the to one level higher than the current level. If X
1088 matched one of our slots, just mark that one. Otherwise, we can't
1089 easily predict which it is, so upgrade all of them. Kept slots
1090 need not be touched.
1092 This is called when an ({...}) construct occurs and a statement
1093 returns a value in memory. */
1096 preserve_temp_slots (rtx x)
1098 struct temp_slot *p = 0;
1100 /* If there is no result, we still might have some objects whose address
1101 were taken, so we need to make sure they stay around. */
1104 for (p = temp_slots; p; p = p->next)
1105 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1111 /* If X is a register that is being used as a pointer, see if we have
1112 a temporary slot we know it points to. To be consistent with
1113 the code below, we really should preserve all non-kept slots
1114 if we can't find a match, but that seems to be much too costly. */
1115 if (GET_CODE (x) == REG && REG_POINTER (x))
1116 p = find_temp_slot_from_address (x);
1118 /* If X is not in memory or is at a constant address, it cannot be in
1119 a temporary slot, but it can contain something whose address was
1121 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1123 for (p = temp_slots; p; p = p->next)
1124 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1130 /* First see if we can find a match. */
1132 p = find_temp_slot_from_address (XEXP (x, 0));
1136 /* Move everything at our level whose address was taken to our new
1137 level in case we used its address. */
1138 struct temp_slot *q;
1140 if (p->level == temp_slot_level)
1142 for (q = temp_slots; q; q = q->next)
1143 if (q != p && q->addr_taken && q->level == p->level)
1152 /* Otherwise, preserve all non-kept slots at this level. */
1153 for (p = temp_slots; p; p = p->next)
1154 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1158 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1159 with that RTL_EXPR, promote it into a temporary slot at the present
1160 level so it will not be freed when we free slots made in the
1164 preserve_rtl_expr_result (rtx x)
1166 struct temp_slot *p;
1168 /* If X is not in memory or is at a constant address, it cannot be in
1169 a temporary slot. */
1170 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1173 /* If we can find a match, move it to our level unless it is already at
1175 p = find_temp_slot_from_address (XEXP (x, 0));
1178 p->level = MIN (p->level, temp_slot_level);
1185 /* Free all temporaries used so far. This is normally called at the end
1186 of generating code for a statement. Don't free any temporaries
1187 currently in use for an RTL_EXPR that hasn't yet been emitted.
1188 We could eventually do better than this since it can be reused while
1189 generating the same RTL_EXPR, but this is complex and probably not
1193 free_temp_slots (void)
1195 struct temp_slot *p;
1197 for (p = temp_slots; p; p = p->next)
1198 if (p->in_use && p->level == temp_slot_level && ! p->keep
1199 && p->rtl_expr == 0)
1202 combine_temp_slots ();
1205 /* Free all temporary slots used in T, an RTL_EXPR node. */
1208 free_temps_for_rtl_expr (tree t)
1210 struct temp_slot *p;
1212 for (p = temp_slots; p; p = p->next)
1213 if (p->rtl_expr == t)
1215 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1216 needs to be preserved. This can happen if a temporary in
1217 the RTL_EXPR was addressed; preserve_temp_slots will move
1218 the temporary into a higher level. */
1219 if (temp_slot_level <= p->level)
1222 p->rtl_expr = NULL_TREE;
1225 combine_temp_slots ();
1228 /* Mark all temporaries ever allocated in this function as not suitable
1229 for reuse until the current level is exited. */
1232 mark_all_temps_used (void)
1234 struct temp_slot *p;
1236 for (p = temp_slots; p; p = p->next)
1238 p->in_use = p->keep = 1;
1239 p->level = MIN (p->level, temp_slot_level);
1243 /* Push deeper into the nesting level for stack temporaries. */
1246 push_temp_slots (void)
1251 /* Pop a temporary nesting level. All slots in use in the current level
1255 pop_temp_slots (void)
1257 struct temp_slot *p;
1259 for (p = temp_slots; p; p = p->next)
1260 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1263 combine_temp_slots ();
1268 /* Initialize temporary slots. */
1271 init_temp_slots (void)
1273 /* We have not allocated any temporaries yet. */
1275 temp_slot_level = 0;
1276 var_temp_slot_level = 0;
1277 target_temp_slot_level = 0;
1280 /* Retroactively move an auto variable from a register to a stack
1281 slot. This is done when an address-reference to the variable is
1282 seen. If RESCAN is true, all previously emitted instructions are
1283 examined and modified to handle the fact that DECL is now
1287 put_var_into_stack (tree decl, int rescan)
1290 enum machine_mode promoted_mode, decl_mode;
1291 struct function *function = 0;
1293 int can_use_addressof;
1294 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1295 int usedp = (TREE_USED (decl)
1296 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1298 context = decl_function_context (decl);
1300 /* Get the current rtl used for this object and its original mode. */
1301 reg = (TREE_CODE (decl) == SAVE_EXPR
1302 ? SAVE_EXPR_RTL (decl)
1303 : DECL_RTL_IF_SET (decl));
1305 /* No need to do anything if decl has no rtx yet
1306 since in that case caller is setting TREE_ADDRESSABLE
1307 and a stack slot will be assigned when the rtl is made. */
1311 /* Get the declared mode for this object. */
1312 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1313 : DECL_MODE (decl));
1314 /* Get the mode it's actually stored in. */
1315 promoted_mode = GET_MODE (reg);
1317 /* If this variable comes from an outer function, find that
1318 function's saved context. Don't use find_function_data here,
1319 because it might not be in any active function.
1320 FIXME: Is that really supposed to happen?
1321 It does in ObjC at least. */
1322 if (context != current_function_decl && context != inline_function_decl)
1323 for (function = outer_function_chain; function; function = function->outer)
1324 if (function->decl == context)
1327 /* If this is a variable-sized object or a structure passed by invisible
1328 reference, with a pseudo to address it, put that pseudo into the stack
1329 if the var is non-local. */
1330 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1331 && GET_CODE (reg) == MEM
1332 && GET_CODE (XEXP (reg, 0)) == REG
1333 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1335 reg = XEXP (reg, 0);
1336 decl_mode = promoted_mode = GET_MODE (reg);
1339 /* If this variable lives in the current function and we don't need to put it
1340 in the stack for the sake of setjmp or the non-locality, try to keep it in
1341 a register until we know we actually need the address. */
1344 && ! (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl))
1346 /* FIXME make it work for promoted modes too */
1347 && decl_mode == promoted_mode
1348 #ifdef NON_SAVING_SETJMP
1349 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1353 /* If we can't use ADDRESSOF, make sure we see through one we already
1355 if (! can_use_addressof && GET_CODE (reg) == MEM
1356 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1357 reg = XEXP (XEXP (reg, 0), 0);
1359 /* Now we should have a value that resides in one or more pseudo regs. */
1361 if (GET_CODE (reg) == REG)
1363 if (can_use_addressof)
1364 gen_mem_addressof (reg, decl, rescan);
1366 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1367 decl_mode, volatilep, 0, usedp, 0);
1369 else if (GET_CODE (reg) == CONCAT)
1371 /* A CONCAT contains two pseudos; put them both in the stack.
1372 We do it so they end up consecutive.
1373 We fixup references to the parts only after we fixup references
1374 to the whole CONCAT, lest we do double fixups for the latter
1376 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1377 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1378 rtx lopart = XEXP (reg, 0);
1379 rtx hipart = XEXP (reg, 1);
1380 #ifdef FRAME_GROWS_DOWNWARD
1381 /* Since part 0 should have a lower address, do it second. */
1382 put_reg_into_stack (function, hipart, part_type, part_mode,
1383 part_mode, volatilep, 0, 0, 0);
1384 put_reg_into_stack (function, lopart, part_type, part_mode,
1385 part_mode, volatilep, 0, 0, 0);
1387 put_reg_into_stack (function, lopart, part_type, part_mode,
1388 part_mode, volatilep, 0, 0, 0);
1389 put_reg_into_stack (function, hipart, part_type, part_mode,
1390 part_mode, volatilep, 0, 0, 0);
1393 /* Change the CONCAT into a combined MEM for both parts. */
1394 PUT_CODE (reg, MEM);
1395 MEM_ATTRS (reg) = 0;
1397 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1398 already computed alias sets. Here we want to re-generate. */
1400 SET_DECL_RTL (decl, NULL);
1401 set_mem_attributes (reg, decl, 1);
1403 SET_DECL_RTL (decl, reg);
1405 /* The two parts are in memory order already.
1406 Use the lower parts address as ours. */
1407 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1408 /* Prevent sharing of rtl that might lose. */
1409 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1410 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1411 if (usedp && rescan)
1413 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1415 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1416 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1423 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1424 into the stack frame of FUNCTION (0 means the current function).
1425 DECL_MODE is the machine mode of the user-level data type.
1426 PROMOTED_MODE is the machine mode of the register.
1427 VOLATILE_P is nonzero if this is for a "volatile" decl.
1428 USED_P is nonzero if this reg might have already been used in an insn. */
1431 put_reg_into_stack (struct function *function, rtx reg, tree type,
1432 enum machine_mode promoted_mode, enum machine_mode decl_mode,
1433 int volatile_p, unsigned int original_regno, int used_p, htab_t ht)
1435 struct function *func = function ? function : cfun;
1437 unsigned int regno = original_regno;
1440 regno = REGNO (reg);
1442 if (regno < func->x_max_parm_reg)
1443 new = func->x_parm_reg_stack_loc[regno];
1446 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1448 PUT_CODE (reg, MEM);
1449 PUT_MODE (reg, decl_mode);
1450 XEXP (reg, 0) = XEXP (new, 0);
1451 MEM_ATTRS (reg) = 0;
1452 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1453 MEM_VOLATILE_P (reg) = volatile_p;
1455 /* If this is a memory ref that contains aggregate components,
1456 mark it as such for cse and loop optimize. If we are reusing a
1457 previously generated stack slot, then we need to copy the bit in
1458 case it was set for other reasons. For instance, it is set for
1459 __builtin_va_alist. */
1462 MEM_SET_IN_STRUCT_P (reg,
1463 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1464 set_mem_alias_set (reg, get_alias_set (type));
1468 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1471 /* Make sure that all refs to the variable, previously made
1472 when it was a register, are fixed up to be valid again.
1473 See function above for meaning of arguments. */
1476 schedule_fixup_var_refs (struct function *function, rtx reg, tree type,
1477 enum machine_mode promoted_mode, htab_t ht)
1479 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1483 struct var_refs_queue *temp;
1485 temp = ggc_alloc (sizeof (struct var_refs_queue));
1486 temp->modified = reg;
1487 temp->promoted_mode = promoted_mode;
1488 temp->unsignedp = unsigned_p;
1489 temp->next = function->fixup_var_refs_queue;
1490 function->fixup_var_refs_queue = temp;
1493 /* Variable is local; fix it up now. */
1494 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1498 fixup_var_refs (rtx var, enum machine_mode promoted_mode, int unsignedp,
1499 rtx may_share, htab_t ht)
1502 rtx first_insn = get_insns ();
1503 struct sequence_stack *stack = seq_stack;
1504 tree rtl_exps = rtl_expr_chain;
1506 /* If there's a hash table, it must record all uses of VAR. */
1511 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1516 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1517 stack == 0, may_share);
1519 /* Scan all pending sequences too. */
1520 for (; stack; stack = stack->next)
1522 push_to_full_sequence (stack->first, stack->last);
1523 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1524 stack->next != 0, may_share);
1525 /* Update remembered end of sequence
1526 in case we added an insn at the end. */
1527 stack->last = get_last_insn ();
1531 /* Scan all waiting RTL_EXPRs too. */
1532 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1534 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1535 if (seq != const0_rtx && seq != 0)
1537 push_to_sequence (seq);
1538 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1545 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1546 some part of an insn. Return a struct fixup_replacement whose OLD
1547 value is equal to X. Allocate a new structure if no such entry exists. */
1549 static struct fixup_replacement *
1550 find_fixup_replacement (struct fixup_replacement **replacements, rtx x)
1552 struct fixup_replacement *p;
1554 /* See if we have already replaced this. */
1555 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1560 p = xmalloc (sizeof (struct fixup_replacement));
1563 p->next = *replacements;
1570 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1571 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1572 for the current function. MAY_SHARE is either a MEM that is not
1573 to be unshared or a list of them. */
1576 fixup_var_refs_insns (rtx insn, rtx var, enum machine_mode promoted_mode,
1577 int unsignedp, int toplevel, rtx may_share)
1581 /* fixup_var_refs_insn might modify insn, so save its next
1583 rtx next = NEXT_INSN (insn);
1585 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1586 the three sequences they (potentially) contain, and process
1587 them recursively. The CALL_INSN itself is not interesting. */
1589 if (GET_CODE (insn) == CALL_INSN
1590 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1594 /* Look at the Normal call, sibling call and tail recursion
1595 sequences attached to the CALL_PLACEHOLDER. */
1596 for (i = 0; i < 3; i++)
1598 rtx seq = XEXP (PATTERN (insn), i);
1601 push_to_sequence (seq);
1602 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1604 XEXP (PATTERN (insn), i) = get_insns ();
1610 else if (INSN_P (insn))
1611 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1618 /* Look up the insns which reference VAR in HT and fix them up. Other
1619 arguments are the same as fixup_var_refs_insns.
1621 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1622 because the hash table will point straight to the interesting insn
1623 (inside the CALL_PLACEHOLDER). */
1626 fixup_var_refs_insns_with_hash (htab_t ht, rtx var, enum machine_mode promoted_mode,
1627 int unsignedp, rtx may_share)
1629 struct insns_for_mem_entry tmp;
1630 struct insns_for_mem_entry *ime;
1634 ime = htab_find (ht, &tmp);
1635 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1636 if (INSN_P (XEXP (insn_list, 0)))
1637 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1638 unsignedp, 1, may_share);
1642 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1643 the insn under examination, VAR is the variable to fix up
1644 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1645 TOPLEVEL is nonzero if this is the main insn chain for this
1649 fixup_var_refs_insn (rtx insn, rtx var, enum machine_mode promoted_mode,
1650 int unsignedp, int toplevel, rtx no_share)
1653 rtx set, prev, prev_set;
1656 /* Remember the notes in case we delete the insn. */
1657 note = REG_NOTES (insn);
1659 /* If this is a CLOBBER of VAR, delete it.
1661 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1662 and REG_RETVAL notes too. */
1663 if (GET_CODE (PATTERN (insn)) == CLOBBER
1664 && (XEXP (PATTERN (insn), 0) == var
1665 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1666 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1667 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1669 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1670 /* The REG_LIBCALL note will go away since we are going to
1671 turn INSN into a NOTE, so just delete the
1672 corresponding REG_RETVAL note. */
1673 remove_note (XEXP (note, 0),
1674 find_reg_note (XEXP (note, 0), REG_RETVAL,
1680 /* The insn to load VAR from a home in the arglist
1681 is now a no-op. When we see it, just delete it.
1682 Similarly if this is storing VAR from a register from which
1683 it was loaded in the previous insn. This will occur
1684 when an ADDRESSOF was made for an arglist slot. */
1686 && (set = single_set (insn)) != 0
1687 && SET_DEST (set) == var
1688 /* If this represents the result of an insn group,
1689 don't delete the insn. */
1690 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1691 && (rtx_equal_p (SET_SRC (set), var)
1692 || (GET_CODE (SET_SRC (set)) == REG
1693 && (prev = prev_nonnote_insn (insn)) != 0
1694 && (prev_set = single_set (prev)) != 0
1695 && SET_DEST (prev_set) == SET_SRC (set)
1696 && rtx_equal_p (SET_SRC (prev_set), var))))
1702 struct fixup_replacement *replacements = 0;
1703 rtx next_insn = NEXT_INSN (insn);
1705 if (SMALL_REGISTER_CLASSES)
1707 /* If the insn that copies the results of a CALL_INSN
1708 into a pseudo now references VAR, we have to use an
1709 intermediate pseudo since we want the life of the
1710 return value register to be only a single insn.
1712 If we don't use an intermediate pseudo, such things as
1713 address computations to make the address of VAR valid
1714 if it is not can be placed between the CALL_INSN and INSN.
1716 To make sure this doesn't happen, we record the destination
1717 of the CALL_INSN and see if the next insn uses both that
1720 if (call_dest != 0 && GET_CODE (insn) == INSN
1721 && reg_mentioned_p (var, PATTERN (insn))
1722 && reg_mentioned_p (call_dest, PATTERN (insn)))
1724 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1726 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1728 PATTERN (insn) = replace_rtx (PATTERN (insn),
1732 if (GET_CODE (insn) == CALL_INSN
1733 && GET_CODE (PATTERN (insn)) == SET)
1734 call_dest = SET_DEST (PATTERN (insn));
1735 else if (GET_CODE (insn) == CALL_INSN
1736 && GET_CODE (PATTERN (insn)) == PARALLEL
1737 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1738 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1743 /* See if we have to do anything to INSN now that VAR is in
1744 memory. If it needs to be loaded into a pseudo, use a single
1745 pseudo for the entire insn in case there is a MATCH_DUP
1746 between two operands. We pass a pointer to the head of
1747 a list of struct fixup_replacements. If fixup_var_refs_1
1748 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1749 it will record them in this list.
1751 If it allocated a pseudo for any replacement, we copy into
1754 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1755 &replacements, no_share);
1757 /* If this is last_parm_insn, and any instructions were output
1758 after it to fix it up, then we must set last_parm_insn to
1759 the last such instruction emitted. */
1760 if (insn == last_parm_insn)
1761 last_parm_insn = PREV_INSN (next_insn);
1763 while (replacements)
1765 struct fixup_replacement *next;
1767 if (GET_CODE (replacements->new) == REG)
1772 /* OLD might be a (subreg (mem)). */
1773 if (GET_CODE (replacements->old) == SUBREG)
1775 = fixup_memory_subreg (replacements->old, insn,
1779 = fixup_stack_1 (replacements->old, insn);
1781 insert_before = insn;
1783 /* If we are changing the mode, do a conversion.
1784 This might be wasteful, but combine.c will
1785 eliminate much of the waste. */
1787 if (GET_MODE (replacements->new)
1788 != GET_MODE (replacements->old))
1791 convert_move (replacements->new,
1792 replacements->old, unsignedp);
1797 seq = gen_move_insn (replacements->new,
1800 emit_insn_before (seq, insert_before);
1803 next = replacements->next;
1804 free (replacements);
1805 replacements = next;
1809 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1810 But don't touch other insns referred to by reg-notes;
1811 we will get them elsewhere. */
1814 if (GET_CODE (note) != INSN_LIST)
1816 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1818 note = XEXP (note, 1);
1822 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1823 See if the rtx expression at *LOC in INSN needs to be changed.
1825 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1826 contain a list of original rtx's and replacements. If we find that we need
1827 to modify this insn by replacing a memory reference with a pseudo or by
1828 making a new MEM to implement a SUBREG, we consult that list to see if
1829 we have already chosen a replacement. If none has already been allocated,
1830 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1831 or the SUBREG, as appropriate, to the pseudo. */
1834 fixup_var_refs_1 (rtx var, enum machine_mode promoted_mode, rtx *loc, rtx insn,
1835 struct fixup_replacement **replacements, rtx no_share)
1839 RTX_CODE code = GET_CODE (x);
1842 struct fixup_replacement *replacement;
1847 if (XEXP (x, 0) == var)
1849 /* Prevent sharing of rtl that might lose. */
1850 rtx sub = copy_rtx (XEXP (var, 0));
1852 if (! validate_change (insn, loc, sub, 0))
1854 rtx y = gen_reg_rtx (GET_MODE (sub));
1857 /* We should be able to replace with a register or all is lost.
1858 Note that we can't use validate_change to verify this, since
1859 we're not caring for replacing all dups simultaneously. */
1860 if (! validate_replace_rtx (*loc, y, insn))
1863 /* Careful! First try to recognize a direct move of the
1864 value, mimicking how things are done in gen_reload wrt
1865 PLUS. Consider what happens when insn is a conditional
1866 move instruction and addsi3 clobbers flags. */
1869 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1873 if (recog_memoized (new_insn) < 0)
1875 /* That failed. Fall back on force_operand and hope. */
1878 sub = force_operand (sub, y);
1880 emit_insn (gen_move_insn (y, sub));
1886 /* Don't separate setter from user. */
1887 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1888 insn = PREV_INSN (insn);
1891 emit_insn_before (seq, insn);
1899 /* If we already have a replacement, use it. Otherwise,
1900 try to fix up this address in case it is invalid. */
1902 replacement = find_fixup_replacement (replacements, var);
1903 if (replacement->new)
1905 *loc = replacement->new;
1909 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1911 /* Unless we are forcing memory to register or we changed the mode,
1912 we can leave things the way they are if the insn is valid. */
1914 INSN_CODE (insn) = -1;
1915 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1916 && recog_memoized (insn) >= 0)
1919 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1923 /* If X contains VAR, we need to unshare it here so that we update
1924 each occurrence separately. But all identical MEMs in one insn
1925 must be replaced with the same rtx because of the possibility of
1928 if (reg_mentioned_p (var, x))
1930 replacement = find_fixup_replacement (replacements, x);
1931 if (replacement->new == 0)
1932 replacement->new = copy_most_rtx (x, no_share);
1934 *loc = x = replacement->new;
1935 code = GET_CODE (x);
1952 /* Note that in some cases those types of expressions are altered
1953 by optimize_bit_field, and do not survive to get here. */
1954 if (XEXP (x, 0) == var
1955 || (GET_CODE (XEXP (x, 0)) == SUBREG
1956 && SUBREG_REG (XEXP (x, 0)) == var))
1958 /* Get TEM as a valid MEM in the mode presently in the insn.
1960 We don't worry about the possibility of MATCH_DUP here; it
1961 is highly unlikely and would be tricky to handle. */
1964 if (GET_CODE (tem) == SUBREG)
1966 if (GET_MODE_BITSIZE (GET_MODE (tem))
1967 > GET_MODE_BITSIZE (GET_MODE (var)))
1969 replacement = find_fixup_replacement (replacements, var);
1970 if (replacement->new == 0)
1971 replacement->new = gen_reg_rtx (GET_MODE (var));
1972 SUBREG_REG (tem) = replacement->new;
1974 /* The following code works only if we have a MEM, so we
1975 need to handle the subreg here. We directly substitute
1976 it assuming that a subreg must be OK here. We already
1977 scheduled a replacement to copy the mem into the
1983 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
1986 tem = fixup_stack_1 (tem, insn);
1988 /* Unless we want to load from memory, get TEM into the proper mode
1989 for an extract from memory. This can only be done if the
1990 extract is at a constant position and length. */
1992 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1993 && GET_CODE (XEXP (x, 2)) == CONST_INT
1994 && ! mode_dependent_address_p (XEXP (tem, 0))
1995 && ! MEM_VOLATILE_P (tem))
1997 enum machine_mode wanted_mode = VOIDmode;
1998 enum machine_mode is_mode = GET_MODE (tem);
1999 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2001 if (GET_CODE (x) == ZERO_EXTRACT)
2003 enum machine_mode new_mode
2004 = mode_for_extraction (EP_extzv, 1);
2005 if (new_mode != MAX_MACHINE_MODE)
2006 wanted_mode = new_mode;
2008 else if (GET_CODE (x) == SIGN_EXTRACT)
2010 enum machine_mode new_mode
2011 = mode_for_extraction (EP_extv, 1);
2012 if (new_mode != MAX_MACHINE_MODE)
2013 wanted_mode = new_mode;
2016 /* If we have a narrower mode, we can do something. */
2017 if (wanted_mode != VOIDmode
2018 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2020 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2021 rtx old_pos = XEXP (x, 2);
2024 /* If the bytes and bits are counted differently, we
2025 must adjust the offset. */
2026 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2027 offset = (GET_MODE_SIZE (is_mode)
2028 - GET_MODE_SIZE (wanted_mode) - offset);
2030 pos %= GET_MODE_BITSIZE (wanted_mode);
2032 newmem = adjust_address_nv (tem, wanted_mode, offset);
2034 /* Make the change and see if the insn remains valid. */
2035 INSN_CODE (insn) = -1;
2036 XEXP (x, 0) = newmem;
2037 XEXP (x, 2) = GEN_INT (pos);
2039 if (recog_memoized (insn) >= 0)
2042 /* Otherwise, restore old position. XEXP (x, 0) will be
2044 XEXP (x, 2) = old_pos;
2048 /* If we get here, the bitfield extract insn can't accept a memory
2049 reference. Copy the input into a register. */
2051 tem1 = gen_reg_rtx (GET_MODE (tem));
2052 emit_insn_before (gen_move_insn (tem1, tem), insn);
2059 if (SUBREG_REG (x) == var)
2061 /* If this is a special SUBREG made because VAR was promoted
2062 from a wider mode, replace it with VAR and call ourself
2063 recursively, this time saying that the object previously
2064 had its current mode (by virtue of the SUBREG). */
2066 if (SUBREG_PROMOTED_VAR_P (x))
2069 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2074 /* If this SUBREG makes VAR wider, it has become a paradoxical
2075 SUBREG with VAR in memory, but these aren't allowed at this
2076 stage of the compilation. So load VAR into a pseudo and take
2077 a SUBREG of that pseudo. */
2078 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2080 replacement = find_fixup_replacement (replacements, var);
2081 if (replacement->new == 0)
2082 replacement->new = gen_reg_rtx (promoted_mode);
2083 SUBREG_REG (x) = replacement->new;
2087 /* See if we have already found a replacement for this SUBREG.
2088 If so, use it. Otherwise, make a MEM and see if the insn
2089 is recognized. If not, or if we should force MEM into a register,
2090 make a pseudo for this SUBREG. */
2091 replacement = find_fixup_replacement (replacements, x);
2092 if (replacement->new)
2094 *loc = replacement->new;
2098 replacement->new = *loc = fixup_memory_subreg (x, insn,
2101 INSN_CODE (insn) = -1;
2102 if (! flag_force_mem && recog_memoized (insn) >= 0)
2105 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2111 /* First do special simplification of bit-field references. */
2112 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2113 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2114 optimize_bit_field (x, insn, 0);
2115 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2116 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2117 optimize_bit_field (x, insn, 0);
2119 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2120 into a register and then store it back out. */
2121 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2122 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2123 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2124 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2125 > GET_MODE_SIZE (GET_MODE (var))))
2127 replacement = find_fixup_replacement (replacements, var);
2128 if (replacement->new == 0)
2129 replacement->new = gen_reg_rtx (GET_MODE (var));
2131 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2132 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2135 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2136 insn into a pseudo and store the low part of the pseudo into VAR. */
2137 if (GET_CODE (SET_DEST (x)) == SUBREG
2138 && SUBREG_REG (SET_DEST (x)) == var
2139 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2140 > GET_MODE_SIZE (GET_MODE (var))))
2142 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2143 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2150 rtx dest = SET_DEST (x);
2151 rtx src = SET_SRC (x);
2152 rtx outerdest = dest;
2154 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2155 || GET_CODE (dest) == SIGN_EXTRACT
2156 || GET_CODE (dest) == ZERO_EXTRACT)
2157 dest = XEXP (dest, 0);
2159 if (GET_CODE (src) == SUBREG)
2160 src = SUBREG_REG (src);
2162 /* If VAR does not appear at the top level of the SET
2163 just scan the lower levels of the tree. */
2165 if (src != var && dest != var)
2168 /* We will need to rerecognize this insn. */
2169 INSN_CODE (insn) = -1;
2171 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2172 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2174 /* Since this case will return, ensure we fixup all the
2176 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2177 insn, replacements, no_share);
2178 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2179 insn, replacements, no_share);
2180 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2181 insn, replacements, no_share);
2183 tem = XEXP (outerdest, 0);
2185 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2186 that may appear inside a ZERO_EXTRACT.
2187 This was legitimate when the MEM was a REG. */
2188 if (GET_CODE (tem) == SUBREG
2189 && SUBREG_REG (tem) == var)
2190 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2192 tem = fixup_stack_1 (tem, insn);
2194 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2195 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2196 && ! mode_dependent_address_p (XEXP (tem, 0))
2197 && ! MEM_VOLATILE_P (tem))
2199 enum machine_mode wanted_mode;
2200 enum machine_mode is_mode = GET_MODE (tem);
2201 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2203 wanted_mode = mode_for_extraction (EP_insv, 0);
2205 /* If we have a narrower mode, we can do something. */
2206 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2208 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2209 rtx old_pos = XEXP (outerdest, 2);
2212 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2213 offset = (GET_MODE_SIZE (is_mode)
2214 - GET_MODE_SIZE (wanted_mode) - offset);
2216 pos %= GET_MODE_BITSIZE (wanted_mode);
2218 newmem = adjust_address_nv (tem, wanted_mode, offset);
2220 /* Make the change and see if the insn remains valid. */
2221 INSN_CODE (insn) = -1;
2222 XEXP (outerdest, 0) = newmem;
2223 XEXP (outerdest, 2) = GEN_INT (pos);
2225 if (recog_memoized (insn) >= 0)
2228 /* Otherwise, restore old position. XEXP (x, 0) will be
2230 XEXP (outerdest, 2) = old_pos;
2234 /* If we get here, the bit-field store doesn't allow memory
2235 or isn't located at a constant position. Load the value into
2236 a register, do the store, and put it back into memory. */
2238 tem1 = gen_reg_rtx (GET_MODE (tem));
2239 emit_insn_before (gen_move_insn (tem1, tem), insn);
2240 emit_insn_after (gen_move_insn (tem, tem1), insn);
2241 XEXP (outerdest, 0) = tem1;
2245 /* STRICT_LOW_PART is a no-op on memory references
2246 and it can cause combinations to be unrecognizable,
2249 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2250 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2252 /* A valid insn to copy VAR into or out of a register
2253 must be left alone, to avoid an infinite loop here.
2254 If the reference to VAR is by a subreg, fix that up,
2255 since SUBREG is not valid for a memref.
2256 Also fix up the address of the stack slot.
2258 Note that we must not try to recognize the insn until
2259 after we know that we have valid addresses and no
2260 (subreg (mem ...) ...) constructs, since these interfere
2261 with determining the validity of the insn. */
2263 if ((SET_SRC (x) == var
2264 || (GET_CODE (SET_SRC (x)) == SUBREG
2265 && SUBREG_REG (SET_SRC (x)) == var))
2266 && (GET_CODE (SET_DEST (x)) == REG
2267 || (GET_CODE (SET_DEST (x)) == SUBREG
2268 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2269 && GET_MODE (var) == promoted_mode
2270 && x == single_set (insn))
2274 if (GET_CODE (SET_SRC (x)) == SUBREG
2275 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2276 > GET_MODE_SIZE (GET_MODE (var))))
2278 /* This (subreg VAR) is now a paradoxical subreg. We need
2279 to replace VAR instead of the subreg. */
2280 replacement = find_fixup_replacement (replacements, var);
2281 if (replacement->new == NULL_RTX)
2282 replacement->new = gen_reg_rtx (GET_MODE (var));
2283 SUBREG_REG (SET_SRC (x)) = replacement->new;
2287 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2288 if (replacement->new)
2289 SET_SRC (x) = replacement->new;
2290 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2291 SET_SRC (x) = replacement->new
2292 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2295 SET_SRC (x) = replacement->new
2296 = fixup_stack_1 (SET_SRC (x), insn);
2299 if (recog_memoized (insn) >= 0)
2302 /* INSN is not valid, but we know that we want to
2303 copy SET_SRC (x) to SET_DEST (x) in some way. So
2304 we generate the move and see whether it requires more
2305 than one insn. If it does, we emit those insns and
2306 delete INSN. Otherwise, we can just replace the pattern
2307 of INSN; we have already verified above that INSN has
2308 no other function that to do X. */
2310 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2311 if (NEXT_INSN (pat) != NULL_RTX)
2313 last = emit_insn_before (pat, insn);
2315 /* INSN might have REG_RETVAL or other important notes, so
2316 we need to store the pattern of the last insn in the
2317 sequence into INSN similarly to the normal case. LAST
2318 should not have REG_NOTES, but we allow them if INSN has
2320 if (REG_NOTES (last) && REG_NOTES (insn))
2322 if (REG_NOTES (last))
2323 REG_NOTES (insn) = REG_NOTES (last);
2324 PATTERN (insn) = PATTERN (last);
2329 PATTERN (insn) = PATTERN (pat);
2334 if ((SET_DEST (x) == var
2335 || (GET_CODE (SET_DEST (x)) == SUBREG
2336 && SUBREG_REG (SET_DEST (x)) == var))
2337 && (GET_CODE (SET_SRC (x)) == REG
2338 || (GET_CODE (SET_SRC (x)) == SUBREG
2339 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2340 && GET_MODE (var) == promoted_mode
2341 && x == single_set (insn))
2345 if (GET_CODE (SET_DEST (x)) == SUBREG)
2346 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2349 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2351 if (recog_memoized (insn) >= 0)
2354 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2355 if (NEXT_INSN (pat) != NULL_RTX)
2357 last = emit_insn_before (pat, insn);
2359 /* INSN might have REG_RETVAL or other important notes, so
2360 we need to store the pattern of the last insn in the
2361 sequence into INSN similarly to the normal case. LAST
2362 should not have REG_NOTES, but we allow them if INSN has
2364 if (REG_NOTES (last) && REG_NOTES (insn))
2366 if (REG_NOTES (last))
2367 REG_NOTES (insn) = REG_NOTES (last);
2368 PATTERN (insn) = PATTERN (last);
2373 PATTERN (insn) = PATTERN (pat);
2378 /* Otherwise, storing into VAR must be handled specially
2379 by storing into a temporary and copying that into VAR
2380 with a new insn after this one. Note that this case
2381 will be used when storing into a promoted scalar since
2382 the insn will now have different modes on the input
2383 and output and hence will be invalid (except for the case
2384 of setting it to a constant, which does not need any
2385 change if it is valid). We generate extra code in that case,
2386 but combine.c will eliminate it. */
2391 rtx fixeddest = SET_DEST (x);
2392 enum machine_mode temp_mode;
2394 /* STRICT_LOW_PART can be discarded, around a MEM. */
2395 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2396 fixeddest = XEXP (fixeddest, 0);
2397 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2398 if (GET_CODE (fixeddest) == SUBREG)
2400 fixeddest = fixup_memory_subreg (fixeddest, insn,
2402 temp_mode = GET_MODE (fixeddest);
2406 fixeddest = fixup_stack_1 (fixeddest, insn);
2407 temp_mode = promoted_mode;
2410 temp = gen_reg_rtx (temp_mode);
2412 emit_insn_after (gen_move_insn (fixeddest,
2413 gen_lowpart (GET_MODE (fixeddest),
2417 SET_DEST (x) = temp;
2425 /* Nothing special about this RTX; fix its operands. */
2427 fmt = GET_RTX_FORMAT (code);
2428 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2431 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2433 else if (fmt[i] == 'E')
2436 for (j = 0; j < XVECLEN (x, i); j++)
2437 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2438 insn, replacements, no_share);
2443 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2444 The REG was placed on the stack, so X now has the form (SUBREG:m1
2447 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2448 must be emitted to compute NEWADDR, put them before INSN.
2450 UNCRITICAL nonzero means accept paradoxical subregs.
2451 This is used for subregs found inside REG_NOTES. */
2454 fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode, int uncritical)
2457 rtx mem = SUBREG_REG (x);
2458 rtx addr = XEXP (mem, 0);
2459 enum machine_mode mode = GET_MODE (x);
2462 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2463 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2466 offset = SUBREG_BYTE (x);
2467 if (BYTES_BIG_ENDIAN)
2468 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2469 the offset so that it points to the right location within the
2471 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2473 if (!flag_force_addr
2474 && memory_address_p (mode, plus_constant (addr, offset)))
2475 /* Shortcut if no insns need be emitted. */
2476 return adjust_address (mem, mode, offset);
2479 result = adjust_address (mem, mode, offset);
2483 emit_insn_before (seq, insn);
2487 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2488 Replace subexpressions of X in place.
2489 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2490 Otherwise return X, with its contents possibly altered.
2492 INSN, PROMOTED_MODE and UNCRITICAL are as for
2493 fixup_memory_subreg. */
2496 walk_fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode,
2506 code = GET_CODE (x);
2508 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2509 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2511 /* Nothing special about this RTX; fix its operands. */
2513 fmt = GET_RTX_FORMAT (code);
2514 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2517 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2518 promoted_mode, uncritical);
2519 else if (fmt[i] == 'E')
2522 for (j = 0; j < XVECLEN (x, i); j++)
2524 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2525 promoted_mode, uncritical);
2531 /* For each memory ref within X, if it refers to a stack slot
2532 with an out of range displacement, put the address in a temp register
2533 (emitting new insns before INSN to load these registers)
2534 and alter the memory ref to use that register.
2535 Replace each such MEM rtx with a copy, to avoid clobberage. */
2538 fixup_stack_1 (rtx x, rtx insn)
2541 RTX_CODE code = GET_CODE (x);
2546 rtx ad = XEXP (x, 0);
2547 /* If we have address of a stack slot but it's not valid
2548 (displacement is too large), compute the sum in a register. */
2549 if (GET_CODE (ad) == PLUS
2550 && GET_CODE (XEXP (ad, 0)) == REG
2551 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2552 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2553 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2554 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2555 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2557 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2558 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2559 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2560 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2563 if (memory_address_p (GET_MODE (x), ad))
2567 temp = copy_to_reg (ad);
2570 emit_insn_before (seq, insn);
2571 return replace_equiv_address (x, temp);
2576 fmt = GET_RTX_FORMAT (code);
2577 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2580 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2581 else if (fmt[i] == 'E')
2584 for (j = 0; j < XVECLEN (x, i); j++)
2585 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2591 /* Optimization: a bit-field instruction whose field
2592 happens to be a byte or halfword in memory
2593 can be changed to a move instruction.
2595 We call here when INSN is an insn to examine or store into a bit-field.
2596 BODY is the SET-rtx to be altered.
2598 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2599 (Currently this is called only from function.c, and EQUIV_MEM
2603 optimize_bit_field (rtx body, rtx insn, rtx *equiv_mem)
2608 enum machine_mode mode;
2610 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2611 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2612 bitfield = SET_DEST (body), destflag = 1;
2614 bitfield = SET_SRC (body), destflag = 0;
2616 /* First check that the field being stored has constant size and position
2617 and is in fact a byte or halfword suitably aligned. */
2619 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2620 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2621 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2623 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2627 /* Now check that the containing word is memory, not a register,
2628 and that it is safe to change the machine mode. */
2630 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2631 memref = XEXP (bitfield, 0);
2632 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2634 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2635 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2636 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2637 memref = SUBREG_REG (XEXP (bitfield, 0));
2638 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2640 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2641 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2644 && ! mode_dependent_address_p (XEXP (memref, 0))
2645 && ! MEM_VOLATILE_P (memref))
2647 /* Now adjust the address, first for any subreg'ing
2648 that we are now getting rid of,
2649 and then for which byte of the word is wanted. */
2651 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2654 /* Adjust OFFSET to count bits from low-address byte. */
2655 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2656 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2657 - offset - INTVAL (XEXP (bitfield, 1)));
2659 /* Adjust OFFSET to count bytes from low-address byte. */
2660 offset /= BITS_PER_UNIT;
2661 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2663 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2664 / UNITS_PER_WORD) * UNITS_PER_WORD;
2665 if (BYTES_BIG_ENDIAN)
2666 offset -= (MIN (UNITS_PER_WORD,
2667 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2668 - MIN (UNITS_PER_WORD,
2669 GET_MODE_SIZE (GET_MODE (memref))));
2673 memref = adjust_address (memref, mode, offset);
2674 insns = get_insns ();
2676 emit_insn_before (insns, insn);
2678 /* Store this memory reference where
2679 we found the bit field reference. */
2683 validate_change (insn, &SET_DEST (body), memref, 1);
2684 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2686 rtx src = SET_SRC (body);
2687 while (GET_CODE (src) == SUBREG
2688 && SUBREG_BYTE (src) == 0)
2689 src = SUBREG_REG (src);
2690 if (GET_MODE (src) != GET_MODE (memref))
2691 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2692 validate_change (insn, &SET_SRC (body), src, 1);
2694 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2695 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2696 /* This shouldn't happen because anything that didn't have
2697 one of these modes should have got converted explicitly
2698 and then referenced through a subreg.
2699 This is so because the original bit-field was
2700 handled by agg_mode and so its tree structure had
2701 the same mode that memref now has. */
2706 rtx dest = SET_DEST (body);
2708 while (GET_CODE (dest) == SUBREG
2709 && SUBREG_BYTE (dest) == 0
2710 && (GET_MODE_CLASS (GET_MODE (dest))
2711 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2712 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2714 dest = SUBREG_REG (dest);
2716 validate_change (insn, &SET_DEST (body), dest, 1);
2718 if (GET_MODE (dest) == GET_MODE (memref))
2719 validate_change (insn, &SET_SRC (body), memref, 1);
2722 /* Convert the mem ref to the destination mode. */
2723 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2726 convert_move (newreg, memref,
2727 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2731 validate_change (insn, &SET_SRC (body), newreg, 1);
2735 /* See if we can convert this extraction or insertion into
2736 a simple move insn. We might not be able to do so if this
2737 was, for example, part of a PARALLEL.
2739 If we succeed, write out any needed conversions. If we fail,
2740 it is hard to guess why we failed, so don't do anything
2741 special; just let the optimization be suppressed. */
2743 if (apply_change_group () && seq)
2744 emit_insn_before (seq, insn);
2749 /* These routines are responsible for converting virtual register references
2750 to the actual hard register references once RTL generation is complete.
2752 The following four variables are used for communication between the
2753 routines. They contain the offsets of the virtual registers from their
2754 respective hard registers. */
2756 static int in_arg_offset;
2757 static int var_offset;
2758 static int dynamic_offset;
2759 static int out_arg_offset;
2760 static int cfa_offset;
2762 /* In most machines, the stack pointer register is equivalent to the bottom
2765 #ifndef STACK_POINTER_OFFSET
2766 #define STACK_POINTER_OFFSET 0
2769 /* If not defined, pick an appropriate default for the offset of dynamically
2770 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2771 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2773 #ifndef STACK_DYNAMIC_OFFSET
2775 /* The bottom of the stack points to the actual arguments. If
2776 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2777 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2778 stack space for register parameters is not pushed by the caller, but
2779 rather part of the fixed stack areas and hence not included in
2780 `current_function_outgoing_args_size'. Nevertheless, we must allow
2781 for it when allocating stack dynamic objects. */
2783 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2784 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2785 ((ACCUMULATE_OUTGOING_ARGS \
2786 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2787 + (STACK_POINTER_OFFSET)) \
2790 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2791 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2792 + (STACK_POINTER_OFFSET))
2796 /* On most machines, the CFA coincides with the first incoming parm. */
2798 #ifndef ARG_POINTER_CFA_OFFSET
2799 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2802 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2803 had its address taken. DECL is the decl or SAVE_EXPR for the
2804 object stored in the register, for later use if we do need to force
2805 REG into the stack. REG is overwritten by the MEM like in
2806 put_reg_into_stack. RESCAN is true if previously emitted
2807 instructions must be rescanned and modified now that the REG has
2808 been transformed. */
2811 gen_mem_addressof (rtx reg, tree decl, int rescan)
2813 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2816 /* Calculate this before we start messing with decl's RTL. */
2817 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2819 /* If the original REG was a user-variable, then so is the REG whose
2820 address is being taken. Likewise for unchanging. */
2821 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2822 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2824 PUT_CODE (reg, MEM);
2825 MEM_ATTRS (reg) = 0;
2830 tree type = TREE_TYPE (decl);
2831 enum machine_mode decl_mode
2832 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2833 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2834 : DECL_RTL_IF_SET (decl));
2836 PUT_MODE (reg, decl_mode);
2838 /* Clear DECL_RTL momentarily so functions below will work
2839 properly, then set it again. */
2840 if (DECL_P (decl) && decl_rtl == reg)
2841 SET_DECL_RTL (decl, 0);
2843 set_mem_attributes (reg, decl, 1);
2844 set_mem_alias_set (reg, set);
2846 if (DECL_P (decl) && decl_rtl == reg)
2847 SET_DECL_RTL (decl, reg);
2850 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0)))
2851 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2854 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2859 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2862 flush_addressof (tree decl)
2864 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2865 && DECL_RTL (decl) != 0
2866 && GET_CODE (DECL_RTL (decl)) == MEM
2867 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2868 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2869 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2872 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2875 put_addressof_into_stack (rtx r, htab_t ht)
2878 int volatile_p, used_p;
2880 rtx reg = XEXP (r, 0);
2882 if (GET_CODE (reg) != REG)
2885 decl = ADDRESSOF_DECL (r);
2888 type = TREE_TYPE (decl);
2889 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2890 && TREE_THIS_VOLATILE (decl));
2891 used_p = (TREE_USED (decl)
2892 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2901 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2902 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2905 /* List of replacements made below in purge_addressof_1 when creating
2906 bitfield insertions. */
2907 static rtx purge_bitfield_addressof_replacements;
2909 /* List of replacements made below in purge_addressof_1 for patterns
2910 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2911 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2912 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2913 enough in complex cases, e.g. when some field values can be
2914 extracted by usage MEM with narrower mode. */
2915 static rtx purge_addressof_replacements;
2917 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2918 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2919 the stack. If the function returns FALSE then the replacement could not
2920 be made. If MAY_POSTPONE is true and we would not put the addressof
2921 to stack, postpone processing of the insn. */
2924 purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
2932 bool libcall = false;
2934 /* Re-start here to avoid recursion in common cases. */
2941 /* Is this a libcall? */
2943 libcall = REG_NOTE_KIND (*loc) == REG_RETVAL;
2945 code = GET_CODE (x);
2947 /* If we don't return in any of the cases below, we will recurse inside
2948 the RTX, which will normally result in any ADDRESSOF being forced into
2952 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1,
2954 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0,
2958 else if (code == ADDRESSOF)
2962 if (GET_CODE (XEXP (x, 0)) != MEM)
2963 put_addressof_into_stack (x, ht);
2965 /* We must create a copy of the rtx because it was created by
2966 overwriting a REG rtx which is always shared. */
2967 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2968 if (validate_change (insn, loc, sub, 0)
2969 || validate_replace_rtx (x, sub, insn))
2974 /* If SUB is a hard or virtual register, try it as a pseudo-register.
2975 Otherwise, perhaps SUB is an expression, so generate code to compute
2977 if (GET_CODE (sub) == REG && REGNO (sub) <= LAST_VIRTUAL_REGISTER)
2978 sub = copy_to_reg (sub);
2980 sub = force_operand (sub, NULL_RTX);
2982 if (! validate_change (insn, loc, sub, 0)
2983 && ! validate_replace_rtx (x, sub, insn))
2986 insns = get_insns ();
2988 emit_insn_before (insns, insn);
2992 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2994 rtx sub = XEXP (XEXP (x, 0), 0);
2996 if (GET_CODE (sub) == MEM)
2997 sub = adjust_address_nv (sub, GET_MODE (x), 0);
2998 else if (GET_CODE (sub) == REG
2999 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3001 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3003 int size_x, size_sub;
3007 /* Postpone for now, so that we do not emit bitfield arithmetics
3008 unless there is some benefit from it. */
3009 if (!postponed_insns || XEXP (postponed_insns, 0) != insn)
3010 postponed_insns = alloc_INSN_LIST (insn, postponed_insns);
3016 /* When processing REG_NOTES look at the list of
3017 replacements done on the insn to find the register that X
3021 for (tem = purge_bitfield_addressof_replacements;
3023 tem = XEXP (XEXP (tem, 1), 1))
3024 if (rtx_equal_p (x, XEXP (tem, 0)))
3026 *loc = XEXP (XEXP (tem, 1), 0);
3030 /* See comment for purge_addressof_replacements. */
3031 for (tem = purge_addressof_replacements;
3033 tem = XEXP (XEXP (tem, 1), 1))
3034 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3036 rtx z = XEXP (XEXP (tem, 1), 0);
3038 if (GET_MODE (x) == GET_MODE (z)
3039 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3040 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3043 /* It can happen that the note may speak of things
3044 in a wider (or just different) mode than the
3045 code did. This is especially true of
3048 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3051 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3052 && (GET_MODE_SIZE (GET_MODE (x))
3053 > GET_MODE_SIZE (GET_MODE (z))))
3055 /* This can occur as a result in invalid
3056 pointer casts, e.g. float f; ...
3057 *(long long int *)&f.
3058 ??? We could emit a warning here, but
3059 without a line number that wouldn't be
3061 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3064 z = gen_lowpart (GET_MODE (x), z);
3070 /* When we are processing the REG_NOTES of the last instruction
3071 of a libcall, there will be typically no replacements
3072 for that insn; the replacements happened before, piecemeal
3073 fashion. OTOH we are not interested in the details of
3074 this for the REG_EQUAL note, we want to know the big picture,
3075 which can be succinctly described with a simple SUBREG.
3076 Note that removing the REG_EQUAL note is not an option
3077 on the last insn of a libcall, so we must do a replacement. */
3079 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
3081 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
3082 [0 S8 A32]), which can be expressed with a simple
3084 if ((GET_MODE_SIZE (GET_MODE (x))
3085 <= GET_MODE_SIZE (GET_MODE (sub)))
3086 /* Again, invalid pointer casts (as in
3087 compile/990203-1.c) can require paradoxical
3089 || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3090 && (GET_MODE_SIZE (GET_MODE (x))
3091 > GET_MODE_SIZE (GET_MODE (sub)))
3094 *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
3097 /* ??? Are there other cases we should handle? */
3099 /* Sometimes we may not be able to find the replacement. For
3100 example when the original insn was a MEM in a wider mode,
3101 and the note is part of a sign extension of a narrowed
3102 version of that MEM. Gcc testcase compile/990829-1.c can
3103 generate an example of this situation. Rather than complain
3104 we return false, which will prompt our caller to remove the
3109 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3110 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3112 /* Do not frob unchanging MEMs. If a later reference forces the
3113 pseudo to the stack, we can wind up with multiple writes to
3114 an unchanging memory, which is invalid. */
3115 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3118 /* Don't even consider working with paradoxical subregs,
3119 or the moral equivalent seen here. */
3120 else if (size_x <= size_sub
3121 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3123 /* Do a bitfield insertion to mirror what would happen
3130 rtx p = PREV_INSN (insn);
3133 val = gen_reg_rtx (GET_MODE (x));
3134 if (! validate_change (insn, loc, val, 0))
3136 /* Discard the current sequence and put the
3137 ADDRESSOF on stack. */
3143 emit_insn_before (seq, insn);
3144 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3148 store_bit_field (sub, size_x, 0, GET_MODE (x),
3149 val, GET_MODE_SIZE (GET_MODE (sub)));
3151 /* Make sure to unshare any shared rtl that store_bit_field
3152 might have created. */
3153 unshare_all_rtl_again (get_insns ());
3157 p = emit_insn_after (seq, insn);
3158 if (NEXT_INSN (insn))
3159 compute_insns_for_mem (NEXT_INSN (insn),
3160 p ? NEXT_INSN (p) : NULL_RTX,
3165 rtx p = PREV_INSN (insn);
3168 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3169 GET_MODE (x), GET_MODE (x),
3170 GET_MODE_SIZE (GET_MODE (sub)));
3172 if (! validate_change (insn, loc, val, 0))
3174 /* Discard the current sequence and put the
3175 ADDRESSOF on stack. */
3182 emit_insn_before (seq, insn);
3183 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3187 /* Remember the replacement so that the same one can be done
3188 on the REG_NOTES. */
3189 purge_bitfield_addressof_replacements
3190 = gen_rtx_EXPR_LIST (VOIDmode, x,
3193 purge_bitfield_addressof_replacements));
3195 /* We replaced with a reg -- all done. */
3200 else if (validate_change (insn, loc, sub, 0))
3202 /* Remember the replacement so that the same one can be done
3203 on the REG_NOTES. */
3204 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3208 for (tem = purge_addressof_replacements;
3210 tem = XEXP (XEXP (tem, 1), 1))
3211 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3213 XEXP (XEXP (tem, 1), 0) = sub;
3216 purge_addressof_replacements
3217 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3218 gen_rtx_EXPR_LIST (VOIDmode, sub,
3219 purge_addressof_replacements));
3227 /* Scan all subexpressions. */
3228 fmt = GET_RTX_FORMAT (code);
3229 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3232 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0,
3234 else if (*fmt == 'E')
3235 for (j = 0; j < XVECLEN (x, i); j++)
3236 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0,
3243 /* Return a hash value for K, a REG. */
3246 insns_for_mem_hash (const void *k)
3248 /* Use the address of the key for the hash value. */
3249 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3250 return htab_hash_pointer (m->key);
3253 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3256 insns_for_mem_comp (const void *k1, const void *k2)
3258 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3259 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3260 return m1->key == m2->key;
3263 struct insns_for_mem_walk_info
3265 /* The hash table that we are using to record which INSNs use which
3269 /* The INSN we are currently processing. */
3272 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3273 to find the insns that use the REGs in the ADDRESSOFs. */
3277 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3278 that might be used in an ADDRESSOF expression, record this INSN in
3279 the hash table given by DATA (which is really a pointer to an
3280 insns_for_mem_walk_info structure). */
3283 insns_for_mem_walk (rtx *r, void *data)
3285 struct insns_for_mem_walk_info *ifmwi
3286 = (struct insns_for_mem_walk_info *) data;
3287 struct insns_for_mem_entry tmp;
3288 tmp.insns = NULL_RTX;
3290 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3291 && GET_CODE (XEXP (*r, 0)) == REG)
3294 tmp.key = XEXP (*r, 0);
3295 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3298 *e = ggc_alloc (sizeof (tmp));
3299 memcpy (*e, &tmp, sizeof (tmp));
3302 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3304 struct insns_for_mem_entry *ifme;
3306 ifme = htab_find (ifmwi->ht, &tmp);
3308 /* If we have not already recorded this INSN, do so now. Since
3309 we process the INSNs in order, we know that if we have
3310 recorded it it must be at the front of the list. */
3311 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3312 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3319 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3320 which REGs in HT. */
3323 compute_insns_for_mem (rtx insns, rtx last_insn, htab_t ht)
3326 struct insns_for_mem_walk_info ifmwi;
3329 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3330 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3334 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3338 /* Helper function for purge_addressof called through for_each_rtx.
3339 Returns true iff the rtl is an ADDRESSOF. */
3342 is_addressof (rtx *rtl, void *data ATTRIBUTE_UNUSED)
3344 return GET_CODE (*rtl) == ADDRESSOF;
3347 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3348 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3352 purge_addressof (rtx insns)
3357 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3358 requires a fixup pass over the instruction stream to correct
3359 INSNs that depended on the REG being a REG, and not a MEM. But,
3360 these fixup passes are slow. Furthermore, most MEMs are not
3361 mentioned in very many instructions. So, we speed up the process
3362 by pre-calculating which REGs occur in which INSNs; that allows
3363 us to perform the fixup passes much more quickly. */
3364 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3365 compute_insns_for_mem (insns, NULL_RTX, ht);
3367 postponed_insns = NULL;
3369 for (insn = insns; insn; insn = NEXT_INSN (insn))
3372 if (! purge_addressof_1 (&PATTERN (insn), insn,
3373 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht))
3374 /* If we could not replace the ADDRESSOFs in the insn,
3375 something is wrong. */
3378 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht))
3380 /* If we could not replace the ADDRESSOFs in the insn's notes,
3381 we can just remove the offending notes instead. */
3384 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3386 /* If we find a REG_RETVAL note then the insn is a libcall.
3387 Such insns must have REG_EQUAL notes as well, in order
3388 for later passes of the compiler to work. So it is not
3389 safe to delete the notes here, and instead we abort. */
3390 if (REG_NOTE_KIND (note) == REG_RETVAL)
3392 if (for_each_rtx (¬e, is_addressof, NULL))
3393 remove_note (insn, note);
3398 /* Process the postponed insns. */
3399 while (postponed_insns)
3401 insn = XEXP (postponed_insns, 0);
3402 tmp = postponed_insns;
3403 postponed_insns = XEXP (postponed_insns, 1);
3404 free_INSN_LIST_node (tmp);
3406 if (! purge_addressof_1 (&PATTERN (insn), insn,
3407 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht))
3412 purge_bitfield_addressof_replacements = 0;
3413 purge_addressof_replacements = 0;
3415 /* REGs are shared. purge_addressof will destructively replace a REG
3416 with a MEM, which creates shared MEMs.
3418 Unfortunately, the children of put_reg_into_stack assume that MEMs
3419 referring to the same stack slot are shared (fixup_var_refs and
3420 the associated hash table code).
3422 So, we have to do another unsharing pass after we have flushed any
3423 REGs that had their address taken into the stack.
3425 It may be worth tracking whether or not we converted any REGs into
3426 MEMs to avoid this overhead when it is not needed. */
3427 unshare_all_rtl_again (get_insns ());
3430 /* Convert a SET of a hard subreg to a set of the appropriate hard
3431 register. A subroutine of purge_hard_subreg_sets. */
3434 purge_single_hard_subreg_set (rtx pattern)
3436 rtx reg = SET_DEST (pattern);
3437 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3440 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3441 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3443 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3444 GET_MODE (SUBREG_REG (reg)),
3447 reg = SUBREG_REG (reg);
3451 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3453 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3454 SET_DEST (pattern) = reg;
3458 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3459 only such SETs that we expect to see are those left in because
3460 integrate can't handle sets of parts of a return value register.
3462 We don't use alter_subreg because we only want to eliminate subregs
3463 of hard registers. */
3466 purge_hard_subreg_sets (rtx insn)
3468 for (; insn; insn = NEXT_INSN (insn))
3472 rtx pattern = PATTERN (insn);
3473 switch (GET_CODE (pattern))
3476 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3477 purge_single_hard_subreg_set (pattern);
3482 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3484 rtx inner_pattern = XVECEXP (pattern, 0, j);
3485 if (GET_CODE (inner_pattern) == SET
3486 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3487 purge_single_hard_subreg_set (inner_pattern);
3498 /* Pass through the INSNS of function FNDECL and convert virtual register
3499 references to hard register references. */
3502 instantiate_virtual_regs (tree fndecl, rtx insns)
3507 /* Compute the offsets to use for this function. */
3508 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3509 var_offset = STARTING_FRAME_OFFSET;
3510 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3511 out_arg_offset = STACK_POINTER_OFFSET;
3512 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3514 /* Scan all variables and parameters of this function. For each that is
3515 in memory, instantiate all virtual registers if the result is a valid
3516 address. If not, we do it later. That will handle most uses of virtual
3517 regs on many machines. */
3518 instantiate_decls (fndecl, 1);
3520 /* Initialize recognition, indicating that volatile is OK. */
3523 /* Scan through all the insns, instantiating every virtual register still
3525 for (insn = insns; insn; insn = NEXT_INSN (insn))
3526 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3527 || GET_CODE (insn) == CALL_INSN)
3529 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3530 if (INSN_DELETED_P (insn))
3532 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3533 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3534 if (GET_CODE (insn) == CALL_INSN)
3535 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3538 /* Past this point all ASM statements should match. Verify that
3539 to avoid failures later in the compilation process. */
3540 if (asm_noperands (PATTERN (insn)) >= 0
3541 && ! check_asm_operands (PATTERN (insn)))
3542 instantiate_virtual_regs_lossage (insn);
3545 /* Instantiate the stack slots for the parm registers, for later use in
3546 addressof elimination. */
3547 for (i = 0; i < max_parm_reg; ++i)
3548 if (parm_reg_stack_loc[i])
3549 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3551 /* Now instantiate the remaining register equivalences for debugging info.
3552 These will not be valid addresses. */
3553 instantiate_decls (fndecl, 0);
3555 /* Indicate that, from now on, assign_stack_local should use
3556 frame_pointer_rtx. */
3557 virtuals_instantiated = 1;
3560 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3561 all virtual registers in their DECL_RTL's.
3563 If VALID_ONLY, do this only if the resulting address is still valid.
3564 Otherwise, always do it. */
3567 instantiate_decls (tree fndecl, int valid_only)
3571 /* Process all parameters of the function. */
3572 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3574 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3575 HOST_WIDE_INT size_rtl;
3577 instantiate_decl (DECL_RTL (decl), size, valid_only);
3579 /* If the parameter was promoted, then the incoming RTL mode may be
3580 larger than the declared type size. We must use the larger of
3582 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3583 size = MAX (size_rtl, size);
3584 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3587 /* Now process all variables defined in the function or its subblocks. */
3588 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3591 /* Subroutine of instantiate_decls: Process all decls in the given
3592 BLOCK node and all its subblocks. */
3595 instantiate_decls_1 (tree let, int valid_only)
3599 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3600 if (DECL_RTL_SET_P (t))
3601 instantiate_decl (DECL_RTL (t),
3602 int_size_in_bytes (TREE_TYPE (t)),
3605 /* Process all subblocks. */
3606 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3607 instantiate_decls_1 (t, valid_only);
3610 /* Subroutine of the preceding procedures: Given RTL representing a
3611 decl and the size of the object, do any instantiation required.
3613 If VALID_ONLY is nonzero, it means that the RTL should only be
3614 changed if the new address is valid. */
3617 instantiate_decl (rtx x, HOST_WIDE_INT size, int valid_only)
3619 enum machine_mode mode;
3622 /* If this is not a MEM, no need to do anything. Similarly if the
3623 address is a constant or a register that is not a virtual register. */
3625 if (x == 0 || GET_CODE (x) != MEM)
3629 if (CONSTANT_P (addr)
3630 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3631 || (GET_CODE (addr) == REG
3632 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3633 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3636 /* If we should only do this if the address is valid, copy the address.
3637 We need to do this so we can undo any changes that might make the
3638 address invalid. This copy is unfortunate, but probably can't be
3642 addr = copy_rtx (addr);
3644 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3646 if (valid_only && size >= 0)
3648 unsigned HOST_WIDE_INT decl_size = size;
3650 /* Now verify that the resulting address is valid for every integer or
3651 floating-point mode up to and including SIZE bytes long. We do this
3652 since the object might be accessed in any mode and frame addresses
3655 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3656 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3657 mode = GET_MODE_WIDER_MODE (mode))
3658 if (! memory_address_p (mode, addr))
3661 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3662 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3663 mode = GET_MODE_WIDER_MODE (mode))
3664 if (! memory_address_p (mode, addr))
3668 /* Put back the address now that we have updated it and we either know
3669 it is valid or we don't care whether it is valid. */
3674 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3675 is a virtual register, return the equivalent hard register and set the
3676 offset indirectly through the pointer. Otherwise, return 0. */
3679 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
3682 HOST_WIDE_INT offset;
3684 if (x == virtual_incoming_args_rtx)
3685 new = arg_pointer_rtx, offset = in_arg_offset;
3686 else if (x == virtual_stack_vars_rtx)
3687 new = frame_pointer_rtx, offset = var_offset;
3688 else if (x == virtual_stack_dynamic_rtx)
3689 new = stack_pointer_rtx, offset = dynamic_offset;
3690 else if (x == virtual_outgoing_args_rtx)
3691 new = stack_pointer_rtx, offset = out_arg_offset;
3692 else if (x == virtual_cfa_rtx)
3693 new = arg_pointer_rtx, offset = cfa_offset;
3702 /* Called when instantiate_virtual_regs has failed to update the instruction.
3703 Usually this means that non-matching instruction has been emit, however for
3704 asm statements it may be the problem in the constraints. */
3706 instantiate_virtual_regs_lossage (rtx insn)
3708 if (asm_noperands (PATTERN (insn)) >= 0)
3710 error_for_asm (insn, "impossible constraint in `asm'");
3716 /* Given a pointer to a piece of rtx and an optional pointer to the
3717 containing object, instantiate any virtual registers present in it.
3719 If EXTRA_INSNS, we always do the replacement and generate
3720 any extra insns before OBJECT. If it zero, we do nothing if replacement
3723 Return 1 if we either had nothing to do or if we were able to do the
3724 needed replacement. Return 0 otherwise; we only return zero if
3725 EXTRA_INSNS is zero.
3727 We first try some simple transformations to avoid the creation of extra
3731 instantiate_virtual_regs_1 (rtx *loc, rtx object, int extra_insns)
3736 HOST_WIDE_INT offset = 0;
3742 /* Re-start here to avoid recursion in common cases. */
3749 /* We may have detected and deleted invalid asm statements. */
3750 if (object && INSN_P (object) && INSN_DELETED_P (object))
3753 code = GET_CODE (x);
3755 /* Check for some special cases. */
3773 /* We are allowed to set the virtual registers. This means that
3774 the actual register should receive the source minus the
3775 appropriate offset. This is used, for example, in the handling
3776 of non-local gotos. */
3777 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3779 rtx src = SET_SRC (x);
3781 /* We are setting the register, not using it, so the relevant
3782 offset is the negative of the offset to use were we using
3785 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3787 /* The only valid sources here are PLUS or REG. Just do
3788 the simplest possible thing to handle them. */
3789 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3791 instantiate_virtual_regs_lossage (object);
3796 if (GET_CODE (src) != REG)
3797 temp = force_operand (src, NULL_RTX);
3800 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3804 emit_insn_before (seq, object);
3807 if (! validate_change (object, &SET_SRC (x), temp, 0)
3809 instantiate_virtual_regs_lossage (object);
3814 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3819 /* Handle special case of virtual register plus constant. */
3820 if (CONSTANT_P (XEXP (x, 1)))
3822 rtx old, new_offset;
3824 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3825 if (GET_CODE (XEXP (x, 0)) == PLUS)
3827 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3829 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3831 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3840 #ifdef POINTERS_EXTEND_UNSIGNED
3841 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3842 we can commute the PLUS and SUBREG because pointers into the
3843 frame are well-behaved. */
3844 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3845 && GET_CODE (XEXP (x, 1)) == CONST_INT
3847 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3849 && validate_change (object, loc,
3850 plus_constant (gen_lowpart (ptr_mode,
3853 + INTVAL (XEXP (x, 1))),
3857 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3859 /* We know the second operand is a constant. Unless the
3860 first operand is a REG (which has been already checked),
3861 it needs to be checked. */
3862 if (GET_CODE (XEXP (x, 0)) != REG)
3870 new_offset = plus_constant (XEXP (x, 1), offset);
3872 /* If the new constant is zero, try to replace the sum with just
3874 if (new_offset == const0_rtx
3875 && validate_change (object, loc, new, 0))
3878 /* Next try to replace the register and new offset.
3879 There are two changes to validate here and we can't assume that
3880 in the case of old offset equals new just changing the register
3881 will yield a valid insn. In the interests of a little efficiency,
3882 however, we only call validate change once (we don't queue up the
3883 changes and then call apply_change_group). */
3887 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3888 : (XEXP (x, 0) = new,
3889 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3897 /* Otherwise copy the new constant into a register and replace
3898 constant with that register. */
3899 temp = gen_reg_rtx (Pmode);
3901 if (validate_change (object, &XEXP (x, 1), temp, 0))
3902 emit_insn_before (gen_move_insn (temp, new_offset), object);
3905 /* If that didn't work, replace this expression with a
3906 register containing the sum. */
3909 new = gen_rtx_PLUS (Pmode, new, new_offset);
3912 temp = force_operand (new, NULL_RTX);
3916 emit_insn_before (seq, object);
3917 if (! validate_change (object, loc, temp, 0)
3918 && ! validate_replace_rtx (x, temp, object))
3920 instantiate_virtual_regs_lossage (object);
3929 /* Fall through to generic two-operand expression case. */
3935 case DIV: case UDIV:
3936 case MOD: case UMOD:
3937 case AND: case IOR: case XOR:
3938 case ROTATERT: case ROTATE:
3939 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3941 case GE: case GT: case GEU: case GTU:
3942 case LE: case LT: case LEU: case LTU:
3943 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3944 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3949 /* Most cases of MEM that convert to valid addresses have already been
3950 handled by our scan of decls. The only special handling we
3951 need here is to make a copy of the rtx to ensure it isn't being
3952 shared if we have to change it to a pseudo.
3954 If the rtx is a simple reference to an address via a virtual register,
3955 it can potentially be shared. In such cases, first try to make it
3956 a valid address, which can also be shared. Otherwise, copy it and
3959 First check for common cases that need no processing. These are
3960 usually due to instantiation already being done on a previous instance
3964 if (CONSTANT_ADDRESS_P (temp)
3965 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3966 || temp == arg_pointer_rtx
3968 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3969 || temp == hard_frame_pointer_rtx
3971 || temp == frame_pointer_rtx)
3974 if (GET_CODE (temp) == PLUS
3975 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3976 && (XEXP (temp, 0) == frame_pointer_rtx
3977 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3978 || XEXP (temp, 0) == hard_frame_pointer_rtx
3980 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3981 || XEXP (temp, 0) == arg_pointer_rtx
3986 if (temp == virtual_stack_vars_rtx
3987 || temp == virtual_incoming_args_rtx
3988 || (GET_CODE (temp) == PLUS
3989 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3990 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3991 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3993 /* This MEM may be shared. If the substitution can be done without
3994 the need to generate new pseudos, we want to do it in place
3995 so all copies of the shared rtx benefit. The call below will
3996 only make substitutions if the resulting address is still
3999 Note that we cannot pass X as the object in the recursive call
4000 since the insn being processed may not allow all valid
4001 addresses. However, if we were not passed on object, we can
4002 only modify X without copying it if X will have a valid
4005 ??? Also note that this can still lose if OBJECT is an insn that
4006 has less restrictions on an address that some other insn.
4007 In that case, we will modify the shared address. This case
4008 doesn't seem very likely, though. One case where this could
4009 happen is in the case of a USE or CLOBBER reference, but we
4010 take care of that below. */
4012 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4013 object ? object : x, 0))
4016 /* Otherwise make a copy and process that copy. We copy the entire
4017 RTL expression since it might be a PLUS which could also be
4019 *loc = x = copy_rtx (x);
4022 /* Fall through to generic unary operation case. */
4025 case STRICT_LOW_PART:
4027 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4028 case SIGN_EXTEND: case ZERO_EXTEND:
4029 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4030 case FLOAT: case FIX:
4031 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4036 case POPCOUNT: case PARITY:
4037 /* These case either have just one operand or we know that we need not
4038 check the rest of the operands. */
4044 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4045 go ahead and make the invalid one, but do it to a copy. For a REG,
4046 just make the recursive call, since there's no chance of a problem. */
4048 if ((GET_CODE (XEXP (x, 0)) == MEM
4049 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4051 || (GET_CODE (XEXP (x, 0)) == REG
4052 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4055 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4060 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4061 in front of this insn and substitute the temporary. */
4062 if ((new = instantiate_new_reg (x, &offset)) != 0)
4064 temp = plus_constant (new, offset);
4065 if (!validate_change (object, loc, temp, 0))
4071 temp = force_operand (temp, NULL_RTX);
4075 emit_insn_before (seq, object);
4076 if (! validate_change (object, loc, temp, 0)
4077 && ! validate_replace_rtx (x, temp, object))
4078 instantiate_virtual_regs_lossage (object);
4085 if (GET_CODE (XEXP (x, 0)) == REG)
4088 else if (GET_CODE (XEXP (x, 0)) == MEM)
4090 /* If we have a (addressof (mem ..)), do any instantiation inside
4091 since we know we'll be making the inside valid when we finally
4092 remove the ADDRESSOF. */
4093 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4102 /* Scan all subexpressions. */
4103 fmt = GET_RTX_FORMAT (code);
4104 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4107 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4110 else if (*fmt == 'E')
4111 for (j = 0; j < XVECLEN (x, i); j++)
4112 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4119 /* Optimization: assuming this function does not receive nonlocal gotos,
4120 delete the handlers for such, as well as the insns to establish
4121 and disestablish them. */
4124 delete_handlers (void)
4127 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4129 /* Delete the handler by turning off the flag that would
4130 prevent jump_optimize from deleting it.
4131 Also permit deletion of the nonlocal labels themselves
4132 if nothing local refers to them. */
4133 if (GET_CODE (insn) == CODE_LABEL)
4137 LABEL_PRESERVE_P (insn) = 0;
4139 /* Remove it from the nonlocal_label list, to avoid confusing
4141 for (t = nonlocal_labels, last_t = 0; t;
4142 last_t = t, t = TREE_CHAIN (t))
4143 if (DECL_RTL (TREE_VALUE (t)) == insn)
4148 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4150 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4153 if (GET_CODE (insn) == INSN)
4157 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4158 if (reg_mentioned_p (t, PATTERN (insn)))
4164 || (nonlocal_goto_stack_level != 0
4165 && reg_mentioned_p (nonlocal_goto_stack_level,
4167 delete_related_insns (insn);
4172 /* Return the first insn following those generated by `assign_parms'. */
4175 get_first_nonparm_insn (void)
4178 return NEXT_INSN (last_parm_insn);
4179 return get_insns ();
4182 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4183 This means a type for which function calls must pass an address to the
4184 function or get an address back from the function.
4185 EXP may be a type node or an expression (whose type is tested). */
4188 aggregate_value_p (tree exp, tree fntype)
4190 int i, regno, nregs;
4193 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4196 switch (TREE_CODE (fntype))
4199 fntype = get_callee_fndecl (fntype);
4200 fntype = fntype ? TREE_TYPE (fntype) : 0;
4203 fntype = TREE_TYPE (fntype);
4208 case IDENTIFIER_NODE:
4212 /* We don't expect other rtl types here. */
4216 if (TREE_CODE (type) == VOID_TYPE)
4218 if (targetm.calls.return_in_memory (type, fntype))
4220 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4221 and thus can't be returned in registers. */
4222 if (TREE_ADDRESSABLE (type))
4224 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4226 /* Make sure we have suitable call-clobbered regs to return
4227 the value in; if not, we must return it in memory. */
4228 reg = hard_function_value (type, 0, 0);
4230 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4232 if (GET_CODE (reg) != REG)
4235 regno = REGNO (reg);
4236 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4237 for (i = 0; i < nregs; i++)
4238 if (! call_used_regs[regno + i])
4243 /* Assign RTL expressions to the function's parameters.
4244 This may involve copying them into registers and using
4245 those registers as the RTL for them. */
4248 assign_parms (tree fndecl)
4251 CUMULATIVE_ARGS args_so_far;
4252 /* Total space needed so far for args on the stack,
4253 given as a constant and a tree-expression. */
4254 struct args_size stack_args_size;
4255 tree fntype = TREE_TYPE (fndecl);
4256 tree fnargs = DECL_ARGUMENTS (fndecl), orig_fnargs;
4257 /* This is used for the arg pointer when referring to stack args. */
4258 rtx internal_arg_pointer;
4259 /* This is a dummy PARM_DECL that we used for the function result if
4260 the function returns a structure. */
4261 tree function_result_decl = 0;
4262 int varargs_setup = 0;
4263 int reg_parm_stack_space ATTRIBUTE_UNUSED = 0;
4264 rtx conversion_insns = 0;
4266 /* Nonzero if function takes extra anonymous args.
4267 This means the last named arg must be on the stack
4268 right before the anonymous ones. */
4270 = (TYPE_ARG_TYPES (fntype) != 0
4271 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4272 != void_type_node));
4274 current_function_stdarg = stdarg;
4276 /* If the reg that the virtual arg pointer will be translated into is
4277 not a fixed reg or is the stack pointer, make a copy of the virtual
4278 arg pointer, and address parms via the copy. The frame pointer is
4279 considered fixed even though it is not marked as such.
4281 The second time through, simply use ap to avoid generating rtx. */
4283 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4284 || ! (fixed_regs[ARG_POINTER_REGNUM]
4285 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4286 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4288 internal_arg_pointer = virtual_incoming_args_rtx;
4289 current_function_internal_arg_pointer = internal_arg_pointer;
4291 stack_args_size.constant = 0;
4292 stack_args_size.var = 0;
4294 /* If struct value address is treated as the first argument, make it so. */
4295 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
4296 && ! current_function_returns_pcc_struct
4297 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
4299 tree type = build_pointer_type (TREE_TYPE (fntype));
4301 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4303 DECL_ARG_TYPE (function_result_decl) = type;
4304 TREE_CHAIN (function_result_decl) = fnargs;
4305 fnargs = function_result_decl;
4308 orig_fnargs = fnargs;
4310 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4311 parm_reg_stack_loc = ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4313 if (SPLIT_COMPLEX_ARGS)
4314 fnargs = split_complex_args (fnargs);
4316 #ifdef REG_PARM_STACK_SPACE
4317 #ifdef MAYBE_REG_PARM_STACK_SPACE
4318 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4320 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4324 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4325 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4327 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl);
4330 /* We haven't yet found an argument that we must push and pretend the
4332 current_function_pretend_args_size = 0;
4334 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4338 enum machine_mode promoted_mode, passed_mode;
4339 enum machine_mode nominal_mode, promoted_nominal_mode;
4341 struct locate_and_pad_arg_data locate;
4342 int passed_pointer = 0;
4343 int did_conversion = 0;
4344 tree passed_type = DECL_ARG_TYPE (parm);
4345 tree nominal_type = TREE_TYPE (parm);
4346 int last_named = 0, named_arg;
4349 int pretend_bytes = 0;
4351 /* Set LAST_NAMED if this is last named arg before last
4357 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4358 if (DECL_NAME (tem))
4364 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4365 most machines, if this is a varargs/stdarg function, then we treat
4366 the last named arg as if it were anonymous too. */
4367 named_arg = targetm.calls.strict_argument_naming (&args_so_far) ? 1 : ! last_named;
4369 if (TREE_TYPE (parm) == error_mark_node
4370 /* This can happen after weird syntax errors
4371 or if an enum type is defined among the parms. */
4372 || TREE_CODE (parm) != PARM_DECL
4373 || passed_type == NULL)
4375 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4376 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4377 TREE_USED (parm) = 1;
4381 /* Find mode of arg as it is passed, and mode of arg
4382 as it should be during execution of this function. */
4383 passed_mode = TYPE_MODE (passed_type);
4384 nominal_mode = TYPE_MODE (nominal_type);
4386 /* If the parm's mode is VOID, its value doesn't matter,
4387 and avoid the usual things like emit_move_insn that could crash. */
4388 if (nominal_mode == VOIDmode)
4390 SET_DECL_RTL (parm, const0_rtx);
4391 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4395 /* If the parm is to be passed as a transparent union, use the
4396 type of the first field for the tests below. We have already
4397 verified that the modes are the same. */
4398 if (DECL_TRANSPARENT_UNION (parm)
4399 || (TREE_CODE (passed_type) == UNION_TYPE
4400 && TYPE_TRANSPARENT_UNION (passed_type)))
4401 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4403 /* See if this arg was passed by invisible reference. It is if
4404 it is an object whose size depends on the contents of the
4405 object itself or if the machine requires these objects be passed
4408 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type))
4409 || TREE_ADDRESSABLE (passed_type)
4410 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4411 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4412 passed_type, named_arg)
4416 passed_type = nominal_type = build_pointer_type (passed_type);
4418 passed_mode = nominal_mode = Pmode;
4420 /* See if the frontend wants to pass this by invisible reference. */
4421 else if (passed_type != nominal_type
4422 && POINTER_TYPE_P (passed_type)
4423 && TREE_TYPE (passed_type) == nominal_type)
4425 nominal_type = passed_type;
4427 passed_mode = nominal_mode = Pmode;
4430 promoted_mode = passed_mode;
4432 if (targetm.calls.promote_function_args (TREE_TYPE (fndecl)))
4434 /* Compute the mode in which the arg is actually extended to. */
4435 unsignedp = TREE_UNSIGNED (passed_type);
4436 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4439 /* Let machine desc say which reg (if any) the parm arrives in.
4440 0 means it arrives on the stack. */
4441 #ifdef FUNCTION_INCOMING_ARG
4442 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4443 passed_type, named_arg);
4445 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4446 passed_type, named_arg);
4449 if (entry_parm == 0)
4450 promoted_mode = passed_mode;
4452 /* If this is the last named parameter, do any required setup for
4453 varargs or stdargs. We need to know about the case of this being an
4454 addressable type, in which case we skip the registers it
4455 would have arrived in.
4457 For stdargs, LAST_NAMED will be set for two parameters, the one that
4458 is actually the last named, and the dummy parameter. We only
4459 want to do this action once.
4461 Also, indicate when RTL generation is to be suppressed. */
4462 if (last_named && !varargs_setup)
4464 int varargs_pretend_bytes = 0;
4465 targetm.calls.setup_incoming_varargs (&args_so_far, promoted_mode,
4467 &varargs_pretend_bytes, 0);
4470 /* If the back-end has requested extra stack space, record how
4471 much is needed. Do not change pretend_args_size otherwise
4472 since it may be nonzero from an earlier partial argument. */
4473 if (varargs_pretend_bytes > 0)
4474 current_function_pretend_args_size = varargs_pretend_bytes;
4477 /* Determine parm's home in the stack,
4478 in case it arrives in the stack or we should pretend it did.
4480 Compute the stack position and rtx where the argument arrives
4483 There is one complexity here: If this was a parameter that would
4484 have been passed in registers, but wasn't only because it is
4485 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4486 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4487 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4488 0 as it was the previous time. */
4489 in_regs = entry_parm != 0;
4490 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4493 if (!in_regs && !named_arg)
4496 targetm.calls.pretend_outgoing_varargs_named (&args_so_far);
4499 #ifdef FUNCTION_INCOMING_ARG
4500 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4502 pretend_named) != 0;
4504 in_regs = FUNCTION_ARG (args_so_far, promoted_mode,
4506 pretend_named) != 0;
4511 /* If this parameter was passed both in registers and in the stack,
4512 use the copy on the stack. */
4513 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4516 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4519 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4520 passed_type, named_arg);
4522 #ifndef MAYBE_REG_PARM_STACK_SPACE
4523 /* The caller might already have allocated stack space
4524 for the register parameters. */
4525 && reg_parm_stack_space == 0
4529 /* Part of this argument is passed in registers and part
4530 is passed on the stack. Ask the prologue code to extend
4531 the stack part so that we can recreate the full value.
4533 PRETEND_BYTES is the size of the registers we need to store.
4534 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
4535 stack space that the prologue should allocate.
4537 Internally, gcc assumes that the argument pointer is
4538 aligned to STACK_BOUNDARY bits. This is used both for
4539 alignment optimizations (see init_emit) and to locate
4540 arguments that are aligned to more than PARM_BOUNDARY
4541 bits. We must preserve this invariant by rounding
4542 CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to a stack
4544 pretend_bytes = partial * UNITS_PER_WORD;
4545 current_function_pretend_args_size
4546 = CEIL_ROUND (pretend_bytes, STACK_BYTES);
4548 /* If PRETEND_BYTES != CURRENT_FUNCTION_PRETEND_ARGS_SIZE,
4549 insert the padding before the start of the first pretend
4551 stack_args_size.constant
4552 = (current_function_pretend_args_size - pretend_bytes);
4557 memset (&locate, 0, sizeof (locate));
4558 locate_and_pad_parm (promoted_mode, passed_type, in_regs,
4559 entry_parm ? partial : 0, fndecl,
4560 &stack_args_size, &locate);
4565 /* If we're passing this arg using a reg, make its stack home
4566 the aligned stack slot. */
4568 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset);
4570 offset_rtx = ARGS_SIZE_RTX (locate.offset);
4572 if (offset_rtx == const0_rtx)
4573 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4575 stack_parm = gen_rtx_MEM (promoted_mode,
4576 gen_rtx_PLUS (Pmode,
4577 internal_arg_pointer,
4580 set_mem_attributes (stack_parm, parm, 1);
4581 if (entry_parm && MEM_ATTRS (stack_parm)->align < PARM_BOUNDARY)
4582 set_mem_align (stack_parm, PARM_BOUNDARY);
4584 /* Set also REG_ATTRS if parameter was passed in a register. */
4586 set_reg_attrs_for_parm (entry_parm, stack_parm);
4589 /* If this parm was passed part in regs and part in memory,
4590 pretend it arrived entirely in memory
4591 by pushing the register-part onto the stack.
4593 In the special case of a DImode or DFmode that is split,
4594 we could put it together in a pseudoreg directly,
4595 but for now that's not worth bothering with. */
4599 /* Handle calls that pass values in multiple non-contiguous
4600 locations. The Irix 6 ABI has examples of this. */
4601 if (GET_CODE (entry_parm) == PARALLEL)
4602 emit_group_store (validize_mem (stack_parm), entry_parm,
4604 int_size_in_bytes (TREE_TYPE (parm)));
4607 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
4610 entry_parm = stack_parm;
4613 /* If we didn't decide this parm came in a register,
4614 by default it came on the stack. */
4615 if (entry_parm == 0)
4616 entry_parm = stack_parm;
4618 /* Record permanently how this parm was passed. */
4619 DECL_INCOMING_RTL (parm) = entry_parm;
4621 /* If there is actually space on the stack for this parm,
4622 count it in stack_args_size; otherwise set stack_parm to 0
4623 to indicate there is no preallocated stack slot for the parm. */
4625 if (entry_parm == stack_parm
4626 || (GET_CODE (entry_parm) == PARALLEL
4627 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4628 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4629 /* On some machines, even if a parm value arrives in a register
4630 there is still an (uninitialized) stack slot allocated for it.
4632 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4633 whether this parameter already has a stack slot allocated,
4634 because an arg block exists only if current_function_args_size
4635 is larger than some threshold, and we haven't calculated that
4636 yet. So, for now, we just assume that stack slots never exist
4638 || REG_PARM_STACK_SPACE (fndecl) > 0
4642 stack_args_size.constant += pretend_bytes + locate.size.constant;
4643 if (locate.size.var)
4644 ADD_PARM_SIZE (stack_args_size, locate.size.var);
4647 /* No stack slot was pushed for this parm. */
4650 /* Update info on where next arg arrives in registers. */
4652 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4653 passed_type, named_arg);
4655 /* If we can't trust the parm stack slot to be aligned enough
4656 for its ultimate type, don't use that slot after entry.
4657 We'll make another stack slot, if we need one. */
4659 unsigned int thisparm_boundary
4660 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4662 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4666 /* If parm was passed in memory, and we need to convert it on entry,
4667 don't store it back in that same slot. */
4668 if (entry_parm == stack_parm
4669 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4672 /* When an argument is passed in multiple locations, we can't
4673 make use of this information, but we can save some copying if
4674 the whole argument is passed in a single register. */
4675 if (GET_CODE (entry_parm) == PARALLEL
4676 && nominal_mode != BLKmode && passed_mode != BLKmode)
4678 int i, len = XVECLEN (entry_parm, 0);
4680 for (i = 0; i < len; i++)
4681 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4682 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4683 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4685 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4687 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4688 DECL_INCOMING_RTL (parm) = entry_parm;
4693 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4694 in the mode in which it arrives.
4695 STACK_PARM is an RTX for a stack slot where the parameter can live
4696 during the function (in case we want to put it there).
4697 STACK_PARM is 0 if no stack slot was pushed for it.
4699 Now output code if necessary to convert ENTRY_PARM to
4700 the type in which this function declares it,
4701 and store that result in an appropriate place,
4702 which may be a pseudo reg, may be STACK_PARM,
4703 or may be a local stack slot if STACK_PARM is 0.
4705 Set DECL_RTL to that place. */
4707 if (GET_CODE (entry_parm) == PARALLEL && nominal_mode != BLKmode)
4709 /* Objects the size of a register can be combined in registers */
4710 rtx parmreg = gen_reg_rtx (nominal_mode);
4711 emit_group_store (parmreg, entry_parm, TREE_TYPE (parm),
4712 int_size_in_bytes (TREE_TYPE (parm)));
4713 SET_DECL_RTL (parm, parmreg);
4716 if (nominal_mode == BLKmode
4717 #ifdef BLOCK_REG_PADDING
4718 || (locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward)
4719 && GET_MODE_SIZE (promoted_mode) < UNITS_PER_WORD)
4721 || GET_CODE (entry_parm) == PARALLEL)
4723 /* If a BLKmode arrives in registers, copy it to a stack slot.
4724 Handle calls that pass values in multiple non-contiguous
4725 locations. The Irix 6 ABI has examples of this. */
4726 if (GET_CODE (entry_parm) == REG
4727 || GET_CODE (entry_parm) == PARALLEL)
4729 int size = int_size_in_bytes (TREE_TYPE (parm));
4730 int size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
4733 /* Note that we will be storing an integral number of words.
4734 So we have to be careful to ensure that we allocate an
4735 integral number of words. We do this below in the
4736 assign_stack_local if space was not allocated in the argument
4737 list. If it was, this will not work if PARM_BOUNDARY is not
4738 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4739 if it becomes a problem. Exception is when BLKmode arrives
4740 with arguments not conforming to word_mode. */
4742 if (stack_parm == 0)
4744 stack_parm = assign_stack_local (BLKmode, size_stored, 0);
4745 PUT_MODE (stack_parm, GET_MODE (entry_parm));
4746 set_mem_attributes (stack_parm, parm, 1);
4748 else if (GET_CODE (entry_parm) == PARALLEL
4749 && GET_MODE(entry_parm) == BLKmode)
4751 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4754 mem = validize_mem (stack_parm);
4756 /* Handle calls that pass values in multiple non-contiguous
4757 locations. The Irix 6 ABI has examples of this. */
4758 if (GET_CODE (entry_parm) == PARALLEL)
4759 emit_group_store (mem, entry_parm, TREE_TYPE (parm), size);
4764 /* If SIZE is that of a mode no bigger than a word, just use
4765 that mode's store operation. */
4766 else if (size <= UNITS_PER_WORD)
4768 enum machine_mode mode
4769 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
4772 #ifdef BLOCK_REG_PADDING
4773 && (size == UNITS_PER_WORD
4774 || (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4775 != (BYTES_BIG_ENDIAN ? upward : downward)))
4779 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
4780 emit_move_insn (change_address (mem, mode, 0), reg);
4783 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
4784 machine must be aligned to the left before storing
4785 to memory. Note that the previous test doesn't
4786 handle all cases (e.g. SIZE == 3). */
4787 else if (size != UNITS_PER_WORD
4788 #ifdef BLOCK_REG_PADDING
4789 && (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4797 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4798 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
4800 x = expand_binop (word_mode, ashl_optab, reg,
4801 GEN_INT (by), 0, 1, OPTAB_WIDEN);
4802 tem = change_address (mem, word_mode, 0);
4803 emit_move_insn (tem, x);
4806 move_block_from_reg (REGNO (entry_parm), mem,
4807 size_stored / UNITS_PER_WORD);
4810 move_block_from_reg (REGNO (entry_parm), mem,
4811 size_stored / UNITS_PER_WORD);
4813 /* If parm is already bound to register pair, don't change
4815 if (! DECL_RTL_SET_P (parm))
4816 SET_DECL_RTL (parm, stack_parm);
4818 else if (! ((! optimize
4819 && ! DECL_REGISTER (parm))
4820 || TREE_SIDE_EFFECTS (parm)
4821 /* If -ffloat-store specified, don't put explicit
4822 float variables into registers. */
4823 || (flag_float_store
4824 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4825 /* Always assign pseudo to structure return or item passed
4826 by invisible reference. */
4827 || passed_pointer || parm == function_result_decl)
4829 /* Store the parm in a pseudoregister during the function, but we
4830 may need to do it in a wider mode. */
4833 unsigned int regno, regnoi = 0, regnor = 0;
4835 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4837 promoted_nominal_mode
4838 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4840 parmreg = gen_reg_rtx (promoted_nominal_mode);
4841 mark_user_reg (parmreg);
4843 /* If this was an item that we received a pointer to, set DECL_RTL
4847 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4849 set_mem_attributes (x, parm, 1);
4850 SET_DECL_RTL (parm, x);
4854 SET_DECL_RTL (parm, parmreg);
4855 maybe_set_unchanging (DECL_RTL (parm), parm);
4858 /* Copy the value into the register. */
4859 if (nominal_mode != passed_mode
4860 || promoted_nominal_mode != promoted_mode)
4863 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4864 mode, by the caller. We now have to convert it to
4865 NOMINAL_MODE, if different. However, PARMREG may be in
4866 a different mode than NOMINAL_MODE if it is being stored
4869 If ENTRY_PARM is a hard register, it might be in a register
4870 not valid for operating in its mode (e.g., an odd-numbered
4871 register for a DFmode). In that case, moves are the only
4872 thing valid, so we can't do a convert from there. This
4873 occurs when the calling sequence allow such misaligned
4876 In addition, the conversion may involve a call, which could
4877 clobber parameters which haven't been copied to pseudo
4878 registers yet. Therefore, we must first copy the parm to
4879 a pseudo reg here, and save the conversion until after all
4880 parameters have been moved. */
4882 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4884 emit_move_insn (tempreg, validize_mem (entry_parm));
4886 push_to_sequence (conversion_insns);
4887 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4889 if (GET_CODE (tempreg) == SUBREG
4890 && GET_MODE (tempreg) == nominal_mode
4891 && GET_CODE (SUBREG_REG (tempreg)) == REG
4892 && nominal_mode == passed_mode
4893 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4894 && GET_MODE_SIZE (GET_MODE (tempreg))
4895 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4897 /* The argument is already sign/zero extended, so note it
4899 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4900 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4903 /* TREE_USED gets set erroneously during expand_assignment. */
4904 save_tree_used = TREE_USED (parm);
4905 expand_assignment (parm,
4906 make_tree (nominal_type, tempreg), 0);
4907 TREE_USED (parm) = save_tree_used;
4908 conversion_insns = get_insns ();
4913 emit_move_insn (parmreg, validize_mem (entry_parm));
4915 /* If we were passed a pointer but the actual value
4916 can safely live in a register, put it in one. */
4917 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4918 /* If by-reference argument was promoted, demote it. */
4919 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4921 && ! DECL_REGISTER (parm))
4922 || TREE_SIDE_EFFECTS (parm)
4923 /* If -ffloat-store specified, don't put explicit
4924 float variables into registers. */
4925 || (flag_float_store
4926 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4928 /* We can't use nominal_mode, because it will have been set to
4929 Pmode above. We must use the actual mode of the parm. */
4930 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4931 mark_user_reg (parmreg);
4932 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4934 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4935 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4936 push_to_sequence (conversion_insns);
4937 emit_move_insn (tempreg, DECL_RTL (parm));
4939 convert_to_mode (GET_MODE (parmreg),
4942 emit_move_insn (parmreg, DECL_RTL (parm));
4943 conversion_insns = get_insns();
4948 emit_move_insn (parmreg, DECL_RTL (parm));
4949 SET_DECL_RTL (parm, parmreg);
4950 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4954 #ifdef FUNCTION_ARG_CALLEE_COPIES
4955 /* If we are passed an arg by reference and it is our responsibility
4956 to make a copy, do it now.
4957 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4958 original argument, so we must recreate them in the call to
4959 FUNCTION_ARG_CALLEE_COPIES. */
4960 /* ??? Later add code to handle the case that if the argument isn't
4961 modified, don't do the copy. */
4963 else if (passed_pointer
4964 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4965 TYPE_MODE (TREE_TYPE (passed_type)),
4966 TREE_TYPE (passed_type),
4968 && ! TREE_ADDRESSABLE (TREE_TYPE (passed_type)))
4971 tree type = TREE_TYPE (passed_type);
4973 /* This sequence may involve a library call perhaps clobbering
4974 registers that haven't been copied to pseudos yet. */
4976 push_to_sequence (conversion_insns);
4978 if (!COMPLETE_TYPE_P (type)
4979 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4980 /* This is a variable sized object. */
4981 copy = gen_rtx_MEM (BLKmode,
4982 allocate_dynamic_stack_space
4983 (expr_size (parm), NULL_RTX,
4984 TYPE_ALIGN (type)));
4986 copy = assign_stack_temp (TYPE_MODE (type),
4987 int_size_in_bytes (type), 1);
4988 set_mem_attributes (copy, parm, 1);
4990 store_expr (parm, copy, 0);
4991 emit_move_insn (parmreg, XEXP (copy, 0));
4992 conversion_insns = get_insns ();
4996 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4998 /* In any case, record the parm's desired stack location
4999 in case we later discover it must live in the stack.
5001 If it is a COMPLEX value, store the stack location for both
5004 if (GET_CODE (parmreg) == CONCAT)
5005 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
5007 regno = REGNO (parmreg);
5009 if (regno >= max_parm_reg)
5012 int old_max_parm_reg = max_parm_reg;
5014 /* It's slow to expand this one register at a time,
5015 but it's also rare and we need max_parm_reg to be
5016 precisely correct. */
5017 max_parm_reg = regno + 1;
5018 new = ggc_realloc (parm_reg_stack_loc,
5019 max_parm_reg * sizeof (rtx));
5020 memset (new + old_max_parm_reg, 0,
5021 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
5022 parm_reg_stack_loc = new;
5025 if (GET_CODE (parmreg) == CONCAT)
5027 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
5029 regnor = REGNO (gen_realpart (submode, parmreg));
5030 regnoi = REGNO (gen_imagpart (submode, parmreg));
5032 if (stack_parm != 0)
5034 parm_reg_stack_loc[regnor]
5035 = gen_realpart (submode, stack_parm);
5036 parm_reg_stack_loc[regnoi]
5037 = gen_imagpart (submode, stack_parm);
5041 parm_reg_stack_loc[regnor] = 0;
5042 parm_reg_stack_loc[regnoi] = 0;
5046 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
5048 /* Mark the register as eliminable if we did no conversion
5049 and it was copied from memory at a fixed offset,
5050 and the arg pointer was not copied to a pseudo-reg.
5051 If the arg pointer is a pseudo reg or the offset formed
5052 an invalid address, such memory-equivalences
5053 as we make here would screw up life analysis for it. */
5054 if (nominal_mode == passed_mode
5057 && GET_CODE (stack_parm) == MEM
5058 && locate.offset.var == 0
5059 && reg_mentioned_p (virtual_incoming_args_rtx,
5060 XEXP (stack_parm, 0)))
5062 rtx linsn = get_last_insn ();
5065 /* Mark complex types separately. */
5066 if (GET_CODE (parmreg) == CONCAT)
5067 /* Scan backwards for the set of the real and
5069 for (sinsn = linsn; sinsn != 0;
5070 sinsn = prev_nonnote_insn (sinsn))
5072 set = single_set (sinsn);
5074 && SET_DEST (set) == regno_reg_rtx [regnoi])
5076 = gen_rtx_EXPR_LIST (REG_EQUIV,
5077 parm_reg_stack_loc[regnoi],
5080 && SET_DEST (set) == regno_reg_rtx [regnor])
5082 = gen_rtx_EXPR_LIST (REG_EQUIV,
5083 parm_reg_stack_loc[regnor],
5086 else if ((set = single_set (linsn)) != 0
5087 && SET_DEST (set) == parmreg)
5089 = gen_rtx_EXPR_LIST (REG_EQUIV,
5090 stack_parm, REG_NOTES (linsn));
5093 /* For pointer data type, suggest pointer register. */
5094 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5095 mark_reg_pointer (parmreg,
5096 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5098 /* If something wants our address, try to use ADDRESSOF. */
5099 if (TREE_ADDRESSABLE (parm))
5101 /* If we end up putting something into the stack,
5102 fixup_var_refs_insns will need to make a pass over
5103 all the instructions. It looks through the pending
5104 sequences -- but it can't see the ones in the
5105 CONVERSION_INSNS, if they're not on the sequence
5106 stack. So, we go back to that sequence, just so that
5107 the fixups will happen. */
5108 push_to_sequence (conversion_insns);
5109 put_var_into_stack (parm, /*rescan=*/true);
5110 conversion_insns = get_insns ();
5116 /* Value must be stored in the stack slot STACK_PARM
5117 during function execution. */
5119 if (promoted_mode != nominal_mode)
5121 /* Conversion is required. */
5122 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5124 emit_move_insn (tempreg, validize_mem (entry_parm));
5126 push_to_sequence (conversion_insns);
5127 entry_parm = convert_to_mode (nominal_mode, tempreg,
5128 TREE_UNSIGNED (TREE_TYPE (parm)));
5130 /* ??? This may need a big-endian conversion on sparc64. */
5131 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5133 conversion_insns = get_insns ();
5138 if (entry_parm != stack_parm)
5140 if (stack_parm == 0)
5143 = assign_stack_local (GET_MODE (entry_parm),
5144 GET_MODE_SIZE (GET_MODE (entry_parm)),
5146 set_mem_attributes (stack_parm, parm, 1);
5149 if (promoted_mode != nominal_mode)
5151 push_to_sequence (conversion_insns);
5152 emit_move_insn (validize_mem (stack_parm),
5153 validize_mem (entry_parm));
5154 conversion_insns = get_insns ();
5158 emit_move_insn (validize_mem (stack_parm),
5159 validize_mem (entry_parm));
5162 SET_DECL_RTL (parm, stack_parm);
5166 if (SPLIT_COMPLEX_ARGS && fnargs != orig_fnargs)
5168 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
5170 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE)
5173 gen_rtx_CONCAT (DECL_MODE (parm),
5175 DECL_RTL (TREE_CHAIN (fnargs))));
5176 DECL_INCOMING_RTL (parm)
5177 = gen_rtx_CONCAT (DECL_MODE (parm),
5178 DECL_INCOMING_RTL (fnargs),
5179 DECL_INCOMING_RTL (TREE_CHAIN (fnargs)));
5180 fnargs = TREE_CHAIN (fnargs);
5184 SET_DECL_RTL (parm, DECL_RTL (fnargs));
5185 DECL_INCOMING_RTL (parm) = DECL_INCOMING_RTL (fnargs);
5187 fnargs = TREE_CHAIN (fnargs);
5191 /* Output all parameter conversion instructions (possibly including calls)
5192 now that all parameters have been copied out of hard registers. */
5193 emit_insn (conversion_insns);
5195 /* If we are receiving a struct value address as the first argument, set up
5196 the RTL for the function result. As this might require code to convert
5197 the transmitted address to Pmode, we do this here to ensure that possible
5198 preliminary conversions of the address have been emitted already. */
5199 if (function_result_decl)
5201 tree result = DECL_RESULT (fndecl);
5202 rtx addr = DECL_RTL (function_result_decl);
5205 addr = convert_memory_address (Pmode, addr);
5206 x = gen_rtx_MEM (DECL_MODE (result), addr);
5207 set_mem_attributes (x, result, 1);
5208 SET_DECL_RTL (result, x);
5211 last_parm_insn = get_last_insn ();
5213 current_function_args_size = stack_args_size.constant;
5215 /* Adjust function incoming argument size for alignment and
5218 #ifdef REG_PARM_STACK_SPACE
5219 #ifndef MAYBE_REG_PARM_STACK_SPACE
5220 current_function_args_size = MAX (current_function_args_size,
5221 REG_PARM_STACK_SPACE (fndecl));
5225 current_function_args_size
5226 = ((current_function_args_size + STACK_BYTES - 1)
5227 / STACK_BYTES) * STACK_BYTES;
5229 #ifdef ARGS_GROW_DOWNWARD
5230 current_function_arg_offset_rtx
5231 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5232 : expand_expr (size_diffop (stack_args_size.var,
5233 size_int (-stack_args_size.constant)),
5234 NULL_RTX, VOIDmode, 0));
5236 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5239 /* See how many bytes, if any, of its args a function should try to pop
5242 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5243 current_function_args_size);
5245 /* For stdarg.h function, save info about
5246 regs and stack space used by the named args. */
5248 current_function_args_info = args_so_far;
5250 /* Set the rtx used for the function return value. Put this in its
5251 own variable so any optimizers that need this information don't have
5252 to include tree.h. Do this here so it gets done when an inlined
5253 function gets output. */
5255 current_function_return_rtx
5256 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5257 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5259 /* If scalar return value was computed in a pseudo-reg, or was a named
5260 return value that got dumped to the stack, copy that to the hard
5262 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5264 tree decl_result = DECL_RESULT (fndecl);
5265 rtx decl_rtl = DECL_RTL (decl_result);
5267 if (REG_P (decl_rtl)
5268 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5269 : DECL_REGISTER (decl_result))
5273 #ifdef FUNCTION_OUTGOING_VALUE
5274 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5277 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5280 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5281 /* The delay slot scheduler assumes that current_function_return_rtx
5282 holds the hard register containing the return value, not a
5283 temporary pseudo. */
5284 current_function_return_rtx = real_decl_rtl;
5289 /* If ARGS contains entries with complex types, split the entry into two
5290 entries of the component type. Return a new list of substitutions are
5291 needed, else the old list. */
5294 split_complex_args (tree args)
5298 /* Before allocating memory, check for the common case of no complex. */
5299 for (p = args; p; p = TREE_CHAIN (p))
5300 if (TREE_CODE (TREE_TYPE (p)) == COMPLEX_TYPE)
5305 args = copy_list (args);
5307 for (p = args; p; p = TREE_CHAIN (p))
5309 tree type = TREE_TYPE (p);
5310 if (TREE_CODE (type) == COMPLEX_TYPE)
5313 tree subtype = TREE_TYPE (type);
5315 /* Rewrite the PARM_DECL's type with its component. */
5316 TREE_TYPE (p) = subtype;
5317 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
5318 DECL_MODE (p) = VOIDmode;
5319 DECL_SIZE (p) = NULL;
5320 DECL_SIZE_UNIT (p) = NULL;
5323 /* Build a second synthetic decl. */
5324 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
5325 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
5326 layout_decl (decl, 0);
5328 /* Splice it in; skip the new decl. */
5329 TREE_CHAIN (decl) = TREE_CHAIN (p);
5330 TREE_CHAIN (p) = decl;
5338 /* Indicate whether REGNO is an incoming argument to the current function
5339 that was promoted to a wider mode. If so, return the RTX for the
5340 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5341 that REGNO is promoted from and whether the promotion was signed or
5345 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
5349 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5350 arg = TREE_CHAIN (arg))
5351 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5352 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5353 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5355 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5356 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5358 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5359 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5360 && mode != DECL_MODE (arg))
5362 *pmode = DECL_MODE (arg);
5363 *punsignedp = unsignedp;
5364 return DECL_INCOMING_RTL (arg);
5372 /* Compute the size and offset from the start of the stacked arguments for a
5373 parm passed in mode PASSED_MODE and with type TYPE.
5375 INITIAL_OFFSET_PTR points to the current offset into the stacked
5378 The starting offset and size for this parm are returned in
5379 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5380 nonzero, the offset is that of stack slot, which is returned in
5381 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5382 padding required from the initial offset ptr to the stack slot.
5384 IN_REGS is nonzero if the argument will be passed in registers. It will
5385 never be set if REG_PARM_STACK_SPACE is not defined.
5387 FNDECL is the function in which the argument was defined.
5389 There are two types of rounding that are done. The first, controlled by
5390 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5391 list to be aligned to the specific boundary (in bits). This rounding
5392 affects the initial and starting offsets, but not the argument size.
5394 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5395 optionally rounds the size of the parm to PARM_BOUNDARY. The
5396 initial offset is not affected by this rounding, while the size always
5397 is and the starting offset may be. */
5399 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5400 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5401 callers pass in the total size of args so far as
5402 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5405 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
5406 int partial, tree fndecl ATTRIBUTE_UNUSED,
5407 struct args_size *initial_offset_ptr,
5408 struct locate_and_pad_arg_data *locate)
5411 enum direction where_pad;
5413 int reg_parm_stack_space = 0;
5414 int part_size_in_regs;
5416 #ifdef REG_PARM_STACK_SPACE
5417 #ifdef MAYBE_REG_PARM_STACK_SPACE
5418 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5420 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5423 /* If we have found a stack parm before we reach the end of the
5424 area reserved for registers, skip that area. */
5427 if (reg_parm_stack_space > 0)
5429 if (initial_offset_ptr->var)
5431 initial_offset_ptr->var
5432 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5433 ssize_int (reg_parm_stack_space));
5434 initial_offset_ptr->constant = 0;
5436 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5437 initial_offset_ptr->constant = reg_parm_stack_space;
5440 #endif /* REG_PARM_STACK_SPACE */
5442 part_size_in_regs = 0;
5443 if (reg_parm_stack_space == 0)
5444 part_size_in_regs = ((partial * UNITS_PER_WORD)
5445 / (PARM_BOUNDARY / BITS_PER_UNIT)
5446 * (PARM_BOUNDARY / BITS_PER_UNIT));
5449 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5450 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5451 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5452 locate->where_pad = where_pad;
5454 #ifdef ARGS_GROW_DOWNWARD
5455 locate->slot_offset.constant = -initial_offset_ptr->constant;
5456 if (initial_offset_ptr->var)
5457 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
5458 initial_offset_ptr->var);
5462 if (where_pad != none
5463 && (!host_integerp (sizetree, 1)
5464 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5465 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5466 SUB_PARM_SIZE (locate->slot_offset, s2);
5469 locate->slot_offset.constant += part_size_in_regs;
5472 #ifdef REG_PARM_STACK_SPACE
5473 || REG_PARM_STACK_SPACE (fndecl) > 0
5476 pad_to_arg_alignment (&locate->slot_offset, boundary,
5477 &locate->alignment_pad);
5479 locate->size.constant = (-initial_offset_ptr->constant
5480 - locate->slot_offset.constant);
5481 if (initial_offset_ptr->var)
5482 locate->size.var = size_binop (MINUS_EXPR,
5483 size_binop (MINUS_EXPR,
5485 initial_offset_ptr->var),
5486 locate->slot_offset.var);
5488 /* Pad_below needs the pre-rounded size to know how much to pad
5490 locate->offset = locate->slot_offset;
5491 if (where_pad == downward)
5492 pad_below (&locate->offset, passed_mode, sizetree);
5494 #else /* !ARGS_GROW_DOWNWARD */
5496 #ifdef REG_PARM_STACK_SPACE
5497 || REG_PARM_STACK_SPACE (fndecl) > 0
5500 pad_to_arg_alignment (initial_offset_ptr, boundary,
5501 &locate->alignment_pad);
5502 locate->slot_offset = *initial_offset_ptr;
5504 #ifdef PUSH_ROUNDING
5505 if (passed_mode != BLKmode)
5506 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5509 /* Pad_below needs the pre-rounded size to know how much to pad below
5510 so this must be done before rounding up. */
5511 locate->offset = locate->slot_offset;
5512 if (where_pad == downward)
5513 pad_below (&locate->offset, passed_mode, sizetree);
5515 if (where_pad != none
5516 && (!host_integerp (sizetree, 1)
5517 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5518 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5520 ADD_PARM_SIZE (locate->size, sizetree);
5522 locate->size.constant -= part_size_in_regs;
5523 #endif /* ARGS_GROW_DOWNWARD */
5526 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5527 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5530 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
5531 struct args_size *alignment_pad)
5533 tree save_var = NULL_TREE;
5534 HOST_WIDE_INT save_constant = 0;
5535 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5536 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
5538 #ifdef SPARC_STACK_BOUNDARY_HACK
5539 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
5540 higher than the real alignment of %sp. However, when it does this,
5541 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
5542 This is a temporary hack while the sparc port is fixed. */
5543 if (SPARC_STACK_BOUNDARY_HACK)
5547 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5549 save_var = offset_ptr->var;
5550 save_constant = offset_ptr->constant;
5553 alignment_pad->var = NULL_TREE;
5554 alignment_pad->constant = 0;
5556 if (boundary > BITS_PER_UNIT)
5558 if (offset_ptr->var)
5560 tree sp_offset_tree = ssize_int (sp_offset);
5561 tree offset = size_binop (PLUS_EXPR,
5562 ARGS_SIZE_TREE (*offset_ptr),
5564 #ifdef ARGS_GROW_DOWNWARD
5565 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
5567 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
5570 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
5571 /* ARGS_SIZE_TREE includes constant term. */
5572 offset_ptr->constant = 0;
5573 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5574 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5579 offset_ptr->constant = -sp_offset +
5580 #ifdef ARGS_GROW_DOWNWARD
5581 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5583 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5585 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5586 alignment_pad->constant = offset_ptr->constant - save_constant;
5592 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
5594 if (passed_mode != BLKmode)
5596 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5597 offset_ptr->constant
5598 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5599 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5600 - GET_MODE_SIZE (passed_mode));
5604 if (TREE_CODE (sizetree) != INTEGER_CST
5605 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5607 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5608 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5610 ADD_PARM_SIZE (*offset_ptr, s2);
5611 SUB_PARM_SIZE (*offset_ptr, sizetree);
5616 /* Walk the tree of blocks describing the binding levels within a function
5617 and warn about uninitialized variables.
5618 This is done after calling flow_analysis and before global_alloc
5619 clobbers the pseudo-regs to hard regs. */
5622 uninitialized_vars_warning (tree block)
5625 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5627 if (warn_uninitialized
5628 && TREE_CODE (decl) == VAR_DECL
5629 /* These warnings are unreliable for and aggregates
5630 because assigning the fields one by one can fail to convince
5631 flow.c that the entire aggregate was initialized.
5632 Unions are troublesome because members may be shorter. */
5633 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5634 && DECL_RTL (decl) != 0
5635 && GET_CODE (DECL_RTL (decl)) == REG
5636 /* Global optimizations can make it difficult to determine if a
5637 particular variable has been initialized. However, a VAR_DECL
5638 with a nonzero DECL_INITIAL had an initializer, so do not
5639 claim it is potentially uninitialized.
5641 When the DECL_INITIAL is NULL call the language hook to tell us
5642 if we want to warn. */
5643 && (DECL_INITIAL (decl) == NULL_TREE || lang_hooks.decl_uninit (decl))
5644 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5645 warning ("%J'%D' might be used uninitialized in this function",
5648 && TREE_CODE (decl) == VAR_DECL
5649 && DECL_RTL (decl) != 0
5650 && GET_CODE (DECL_RTL (decl)) == REG
5651 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5652 warning ("%Jvariable '%D' might be clobbered by `longjmp' or `vfork'",
5655 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5656 uninitialized_vars_warning (sub);
5659 /* Do the appropriate part of uninitialized_vars_warning
5660 but for arguments instead of local variables. */
5663 setjmp_args_warning (void)
5666 for (decl = DECL_ARGUMENTS (current_function_decl);
5667 decl; decl = TREE_CHAIN (decl))
5668 if (DECL_RTL (decl) != 0
5669 && GET_CODE (DECL_RTL (decl)) == REG
5670 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5671 warning ("%Jargument '%D' might be clobbered by `longjmp' or `vfork'",
5675 /* If this function call setjmp, put all vars into the stack
5676 unless they were declared `register'. */
5679 setjmp_protect (tree block)
5682 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5683 if ((TREE_CODE (decl) == VAR_DECL
5684 || TREE_CODE (decl) == PARM_DECL)
5685 && DECL_RTL (decl) != 0
5686 && (GET_CODE (DECL_RTL (decl)) == REG
5687 || (GET_CODE (DECL_RTL (decl)) == MEM
5688 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5689 /* If this variable came from an inline function, it must be
5690 that its life doesn't overlap the setjmp. If there was a
5691 setjmp in the function, it would already be in memory. We
5692 must exclude such variable because their DECL_RTL might be
5693 set to strange things such as virtual_stack_vars_rtx. */
5694 && ! DECL_FROM_INLINE (decl)
5696 #ifdef NON_SAVING_SETJMP
5697 /* If longjmp doesn't restore the registers,
5698 don't put anything in them. */
5702 ! DECL_REGISTER (decl)))
5703 put_var_into_stack (decl, /*rescan=*/true);
5704 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5705 setjmp_protect (sub);
5708 /* Like the previous function, but for args instead of local variables. */
5711 setjmp_protect_args (void)
5714 for (decl = DECL_ARGUMENTS (current_function_decl);
5715 decl; decl = TREE_CHAIN (decl))
5716 if ((TREE_CODE (decl) == VAR_DECL
5717 || TREE_CODE (decl) == PARM_DECL)
5718 && DECL_RTL (decl) != 0
5719 && (GET_CODE (DECL_RTL (decl)) == REG
5720 || (GET_CODE (DECL_RTL (decl)) == MEM
5721 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5723 /* If longjmp doesn't restore the registers,
5724 don't put anything in them. */
5725 #ifdef NON_SAVING_SETJMP
5729 ! DECL_REGISTER (decl)))
5730 put_var_into_stack (decl, /*rescan=*/true);
5733 /* Return the context-pointer register corresponding to DECL,
5734 or 0 if it does not need one. */
5737 lookup_static_chain (tree decl)
5739 tree context = decl_function_context (decl);
5743 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5746 /* We treat inline_function_decl as an alias for the current function
5747 because that is the inline function whose vars, types, etc.
5748 are being merged into the current function.
5749 See expand_inline_function. */
5750 if (context == current_function_decl || context == inline_function_decl)
5751 return virtual_stack_vars_rtx;
5753 for (link = context_display; link; link = TREE_CHAIN (link))
5754 if (TREE_PURPOSE (link) == context)
5755 return RTL_EXPR_RTL (TREE_VALUE (link));
5760 /* Convert a stack slot address ADDR for variable VAR
5761 (from a containing function)
5762 into an address valid in this function (using a static chain). */
5765 fix_lexical_addr (rtx addr, tree var)
5768 HOST_WIDE_INT displacement;
5769 tree context = decl_function_context (var);
5770 struct function *fp;
5773 /* If this is the present function, we need not do anything. */
5774 if (context == current_function_decl || context == inline_function_decl)
5777 fp = find_function_data (context);
5779 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5780 addr = XEXP (XEXP (addr, 0), 0);
5782 /* Decode given address as base reg plus displacement. */
5783 if (GET_CODE (addr) == REG)
5784 basereg = addr, displacement = 0;
5785 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5786 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5790 /* We accept vars reached via the containing function's
5791 incoming arg pointer and via its stack variables pointer. */
5792 if (basereg == fp->internal_arg_pointer)
5794 /* If reached via arg pointer, get the arg pointer value
5795 out of that function's stack frame.
5797 There are two cases: If a separate ap is needed, allocate a
5798 slot in the outer function for it and dereference it that way.
5799 This is correct even if the real ap is actually a pseudo.
5800 Otherwise, just adjust the offset from the frame pointer to
5803 #ifdef NEED_SEPARATE_AP
5806 addr = get_arg_pointer_save_area (fp);
5807 addr = fix_lexical_addr (XEXP (addr, 0), var);
5808 addr = memory_address (Pmode, addr);
5810 base = gen_rtx_MEM (Pmode, addr);
5811 set_mem_alias_set (base, get_frame_alias_set ());
5812 base = copy_to_reg (base);
5814 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5815 base = lookup_static_chain (var);
5819 else if (basereg == virtual_stack_vars_rtx)
5821 /* This is the same code as lookup_static_chain, duplicated here to
5822 avoid an extra call to decl_function_context. */
5825 for (link = context_display; link; link = TREE_CHAIN (link))
5826 if (TREE_PURPOSE (link) == context)
5828 base = RTL_EXPR_RTL (TREE_VALUE (link));
5836 /* Use same offset, relative to appropriate static chain or argument
5838 return plus_constant (base, displacement);
5841 /* Return the address of the trampoline for entering nested fn FUNCTION.
5842 If necessary, allocate a trampoline (in the stack frame)
5843 and emit rtl to initialize its contents (at entry to this function). */
5846 trampoline_address (tree function)
5851 struct function *fp;
5854 /* Find an existing trampoline and return it. */
5855 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5856 if (TREE_PURPOSE (link) == function)
5858 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5860 for (fp = outer_function_chain; fp; fp = fp->outer)
5861 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5862 if (TREE_PURPOSE (link) == function)
5864 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5866 return adjust_trampoline_addr (tramp);
5869 /* None exists; we must make one. */
5871 /* Find the `struct function' for the function containing FUNCTION. */
5873 fn_context = decl_function_context (function);
5874 if (fn_context != current_function_decl
5875 && fn_context != inline_function_decl)
5876 fp = find_function_data (fn_context);
5878 /* Allocate run-time space for this trampoline. */
5879 /* If rounding needed, allocate extra space
5880 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5881 #define TRAMPOLINE_REAL_SIZE \
5882 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5883 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5885 /* Record the trampoline for reuse and note it for later initialization
5886 by expand_function_end. */
5889 rtlexp = make_node (RTL_EXPR);
5890 RTL_EXPR_RTL (rtlexp) = tramp;
5891 fp->x_trampoline_list = tree_cons (function, rtlexp,
5892 fp->x_trampoline_list);
5896 /* Make the RTL_EXPR node temporary, not momentary, so that the
5897 trampoline_list doesn't become garbage. */
5898 rtlexp = make_node (RTL_EXPR);
5900 RTL_EXPR_RTL (rtlexp) = tramp;
5901 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5904 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5905 return adjust_trampoline_addr (tramp);
5908 /* Given a trampoline address,
5909 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5912 round_trampoline_addr (rtx tramp)
5914 /* Round address up to desired boundary. */
5915 rtx temp = gen_reg_rtx (Pmode);
5916 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5917 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5919 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5920 temp, 0, OPTAB_LIB_WIDEN);
5921 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5922 temp, 0, OPTAB_LIB_WIDEN);
5927 /* Given a trampoline address, round it then apply any
5928 platform-specific adjustments so that the result can be used for a
5932 adjust_trampoline_addr (rtx tramp)
5934 tramp = round_trampoline_addr (tramp);
5935 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5936 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5941 /* Put all this function's BLOCK nodes including those that are chained
5942 onto the first block into a vector, and return it.
5943 Also store in each NOTE for the beginning or end of a block
5944 the index of that block in the vector.
5945 The arguments are BLOCK, the chain of top-level blocks of the function,
5946 and INSNS, the insn chain of the function. */
5949 identify_blocks (void)
5952 tree *block_vector, *last_block_vector;
5954 tree block = DECL_INITIAL (current_function_decl);
5959 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5960 depth-first order. */
5961 block_vector = get_block_vector (block, &n_blocks);
5962 block_stack = xmalloc (n_blocks * sizeof (tree));
5964 last_block_vector = identify_blocks_1 (get_insns (),
5966 block_vector + n_blocks,
5969 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5970 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5971 if (0 && last_block_vector != block_vector + n_blocks)
5974 free (block_vector);
5978 /* Subroutine of identify_blocks. Do the block substitution on the
5979 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5981 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5982 BLOCK_VECTOR is incremented for each block seen. */
5985 identify_blocks_1 (rtx insns, tree *block_vector, tree *end_block_vector,
5986 tree *orig_block_stack)
5989 tree *block_stack = orig_block_stack;
5991 for (insn = insns; insn; insn = NEXT_INSN (insn))
5993 if (GET_CODE (insn) == NOTE)
5995 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5999 /* If there are more block notes than BLOCKs, something
6001 if (block_vector == end_block_vector)
6004 b = *block_vector++;
6005 NOTE_BLOCK (insn) = b;
6008 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6010 /* If there are more NOTE_INSN_BLOCK_ENDs than
6011 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
6012 if (block_stack == orig_block_stack)
6015 NOTE_BLOCK (insn) = *--block_stack;
6018 else if (GET_CODE (insn) == CALL_INSN
6019 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6021 rtx cp = PATTERN (insn);
6023 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
6024 end_block_vector, block_stack);
6026 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
6027 end_block_vector, block_stack);
6029 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
6030 end_block_vector, block_stack);
6034 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
6035 something is badly wrong. */
6036 if (block_stack != orig_block_stack)
6039 return block_vector;
6042 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
6043 and create duplicate blocks. */
6044 /* ??? Need an option to either create block fragments or to create
6045 abstract origin duplicates of a source block. It really depends
6046 on what optimization has been performed. */
6049 reorder_blocks (void)
6051 tree block = DECL_INITIAL (current_function_decl);
6052 varray_type block_stack;
6054 if (block == NULL_TREE)
6057 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
6059 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
6060 reorder_blocks_0 (block);
6062 /* Prune the old trees away, so that they don't get in the way. */
6063 BLOCK_SUBBLOCKS (block) = NULL_TREE;
6064 BLOCK_CHAIN (block) = NULL_TREE;
6066 /* Recreate the block tree from the note nesting. */
6067 reorder_blocks_1 (get_insns (), block, &block_stack);
6068 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
6070 /* Remove deleted blocks from the block fragment chains. */
6071 reorder_fix_fragments (block);
6074 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
6077 reorder_blocks_0 (tree block)
6081 TREE_ASM_WRITTEN (block) = 0;
6082 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
6083 block = BLOCK_CHAIN (block);
6088 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack)
6092 for (insn = insns; insn; insn = NEXT_INSN (insn))
6094 if (GET_CODE (insn) == NOTE)
6096 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6098 tree block = NOTE_BLOCK (insn);
6100 /* If we have seen this block before, that means it now
6101 spans multiple address regions. Create a new fragment. */
6102 if (TREE_ASM_WRITTEN (block))
6104 tree new_block = copy_node (block);
6107 origin = (BLOCK_FRAGMENT_ORIGIN (block)
6108 ? BLOCK_FRAGMENT_ORIGIN (block)
6110 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
6111 BLOCK_FRAGMENT_CHAIN (new_block)
6112 = BLOCK_FRAGMENT_CHAIN (origin);
6113 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
6115 NOTE_BLOCK (insn) = new_block;
6119 BLOCK_SUBBLOCKS (block) = 0;
6120 TREE_ASM_WRITTEN (block) = 1;
6121 /* When there's only one block for the entire function,
6122 current_block == block and we mustn't do this, it
6123 will cause infinite recursion. */
6124 if (block != current_block)
6126 BLOCK_SUPERCONTEXT (block) = current_block;
6127 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6128 BLOCK_SUBBLOCKS (current_block) = block;
6129 current_block = block;
6131 VARRAY_PUSH_TREE (*p_block_stack, block);
6133 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6135 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6136 VARRAY_POP (*p_block_stack);
6137 BLOCK_SUBBLOCKS (current_block)
6138 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6139 current_block = BLOCK_SUPERCONTEXT (current_block);
6142 else if (GET_CODE (insn) == CALL_INSN
6143 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6145 rtx cp = PATTERN (insn);
6146 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
6148 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6150 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6155 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6156 appears in the block tree, select one of the fragments to become
6157 the new origin block. */
6160 reorder_fix_fragments (tree block)
6164 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6165 tree new_origin = NULL_TREE;
6169 if (! TREE_ASM_WRITTEN (dup_origin))
6171 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6173 /* Find the first of the remaining fragments. There must
6174 be at least one -- the current block. */
6175 while (! TREE_ASM_WRITTEN (new_origin))
6176 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6177 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6180 else if (! dup_origin)
6183 /* Re-root the rest of the fragments to the new origin. In the
6184 case that DUP_ORIGIN was null, that means BLOCK was the origin
6185 of a chain of fragments and we want to remove those fragments
6186 that didn't make it to the output. */
6189 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6194 if (TREE_ASM_WRITTEN (chain))
6196 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6198 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6200 chain = BLOCK_FRAGMENT_CHAIN (chain);
6205 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6206 block = BLOCK_CHAIN (block);
6210 /* Reverse the order of elements in the chain T of blocks,
6211 and return the new head of the chain (old last element). */
6214 blocks_nreverse (tree t)
6216 tree prev = 0, decl, next;
6217 for (decl = t; decl; decl = next)
6219 next = BLOCK_CHAIN (decl);
6220 BLOCK_CHAIN (decl) = prev;
6226 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6227 non-NULL, list them all into VECTOR, in a depth-first preorder
6228 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6232 all_blocks (tree block, tree *vector)
6238 TREE_ASM_WRITTEN (block) = 0;
6240 /* Record this block. */
6242 vector[n_blocks] = block;
6246 /* Record the subblocks, and their subblocks... */
6247 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6248 vector ? vector + n_blocks : 0);
6249 block = BLOCK_CHAIN (block);
6255 /* Return a vector containing all the blocks rooted at BLOCK. The
6256 number of elements in the vector is stored in N_BLOCKS_P. The
6257 vector is dynamically allocated; it is the caller's responsibility
6258 to call `free' on the pointer returned. */
6261 get_block_vector (tree block, int *n_blocks_p)
6265 *n_blocks_p = all_blocks (block, NULL);
6266 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
6267 all_blocks (block, block_vector);
6269 return block_vector;
6272 static GTY(()) int next_block_index = 2;
6274 /* Set BLOCK_NUMBER for all the blocks in FN. */
6277 number_blocks (tree fn)
6283 /* For SDB and XCOFF debugging output, we start numbering the blocks
6284 from 1 within each function, rather than keeping a running
6286 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6287 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6288 next_block_index = 1;
6291 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6293 /* The top-level BLOCK isn't numbered at all. */
6294 for (i = 1; i < n_blocks; ++i)
6295 /* We number the blocks from two. */
6296 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6298 free (block_vector);
6303 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6306 debug_find_var_in_block_tree (tree var, tree block)
6310 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6314 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6316 tree ret = debug_find_var_in_block_tree (var, t);
6324 /* Allocate a function structure for FNDECL and set its contents
6328 allocate_struct_function (tree fndecl)
6332 cfun = ggc_alloc_cleared (sizeof (struct function));
6334 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6336 cfun->stack_alignment_needed = STACK_BOUNDARY;
6337 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6339 current_function_funcdef_no = funcdef_no++;
6341 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6343 init_stmt_for_function ();
6344 init_eh_for_function ();
6347 init_varasm_status (cfun);
6349 (*lang_hooks.function.init) (cfun);
6350 if (init_machine_status)
6351 cfun->machine = (*init_machine_status) ();
6356 DECL_SAVED_INSNS (fndecl) = cfun;
6357 cfun->decl = fndecl;
6359 current_function_name = (*lang_hooks.decl_printable_name) (fndecl, 2);
6361 result = DECL_RESULT (fndecl);
6362 if (aggregate_value_p (result, fndecl))
6364 #ifdef PCC_STATIC_STRUCT_RETURN
6365 current_function_returns_pcc_struct = 1;
6367 current_function_returns_struct = 1;
6370 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
6372 current_function_needs_context
6373 = (decl_function_context (current_function_decl) != 0
6374 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6377 /* Reset cfun, and other non-struct-function variables to defaults as
6378 appropriate for emitting rtl at the start of a function. */
6381 prepare_function_start (tree fndecl)
6383 if (fndecl && DECL_SAVED_INSNS (fndecl))
6384 cfun = DECL_SAVED_INSNS (fndecl);
6386 allocate_struct_function (fndecl);
6388 cse_not_expected = ! optimize;
6390 /* Caller save not needed yet. */
6391 caller_save_needed = 0;
6393 /* We haven't done register allocation yet. */
6396 /* Indicate that we need to distinguish between the return value of the
6397 present function and the return value of a function being called. */
6398 rtx_equal_function_value_matters = 1;
6400 /* Indicate that we have not instantiated virtual registers yet. */
6401 virtuals_instantiated = 0;
6403 /* Indicate that we want CONCATs now. */
6404 generating_concat_p = 1;
6406 /* Indicate we have no need of a frame pointer yet. */
6407 frame_pointer_needed = 0;
6410 /* Initialize the rtl expansion mechanism so that we can do simple things
6411 like generate sequences. This is used to provide a context during global
6412 initialization of some passes. */
6414 init_dummy_function_start (void)
6416 prepare_function_start (NULL);
6419 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6420 and initialize static variables for generating RTL for the statements
6424 init_function_start (tree subr)
6426 prepare_function_start (subr);
6428 /* Within function body, compute a type's size as soon it is laid out. */
6429 immediate_size_expand++;
6431 /* Prevent ever trying to delete the first instruction of a
6432 function. Also tell final how to output a linenum before the
6433 function prologue. Note linenums could be missing, e.g. when
6434 compiling a Java .class file. */
6435 if (DECL_SOURCE_LINE (subr))
6436 emit_line_note (DECL_SOURCE_LOCATION (subr));
6438 /* Make sure first insn is a note even if we don't want linenums.
6439 This makes sure the first insn will never be deleted.
6440 Also, final expects a note to appear there. */
6441 emit_note (NOTE_INSN_DELETED);
6443 /* Warn if this value is an aggregate type,
6444 regardless of which calling convention we are using for it. */
6445 if (warn_aggregate_return
6446 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6447 warning ("function returns an aggregate");
6450 /* Make sure all values used by the optimization passes have sane
6453 init_function_for_compilation (void)
6457 /* No prologue/epilogue insns yet. */
6458 VARRAY_GROW (prologue, 0);
6459 VARRAY_GROW (epilogue, 0);
6460 VARRAY_GROW (sibcall_epilogue, 0);
6463 /* Expand a call to __main at the beginning of a possible main function. */
6465 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6466 #undef HAS_INIT_SECTION
6467 #define HAS_INIT_SECTION
6471 expand_main_function (void)
6473 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6474 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6476 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6480 /* Forcibly align the stack. */
6481 #ifdef STACK_GROWS_DOWNWARD
6482 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6483 stack_pointer_rtx, 1, OPTAB_WIDEN);
6485 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6486 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6487 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6488 stack_pointer_rtx, 1, OPTAB_WIDEN);
6490 if (tmp != stack_pointer_rtx)
6491 emit_move_insn (stack_pointer_rtx, tmp);
6493 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6494 tmp = force_reg (Pmode, const0_rtx);
6495 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6499 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6500 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6503 emit_insn_before (seq, tmp);
6509 #ifndef HAS_INIT_SECTION
6510 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6514 /* The PENDING_SIZES represent the sizes of variable-sized types.
6515 Create RTL for the various sizes now (using temporary variables),
6516 so that we can refer to the sizes from the RTL we are generating
6517 for the current function. The PENDING_SIZES are a TREE_LIST. The
6518 TREE_VALUE of each node is a SAVE_EXPR. */
6521 expand_pending_sizes (tree pending_sizes)
6525 /* Evaluate now the sizes of any types declared among the arguments. */
6526 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6528 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6529 /* Flush the queue in case this parameter declaration has
6535 /* Start the RTL for a new function, and set variables used for
6537 SUBR is the FUNCTION_DECL node.
6538 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6539 the function's parameters, which must be run at any return statement. */
6542 expand_function_start (tree subr, int parms_have_cleanups)
6545 rtx last_ptr = NULL_RTX;
6547 /* Make sure volatile mem refs aren't considered
6548 valid operands of arithmetic insns. */
6549 init_recog_no_volatile ();
6551 current_function_instrument_entry_exit
6552 = (flag_instrument_function_entry_exit
6553 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6555 current_function_profile
6557 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6559 current_function_limit_stack
6560 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6562 /* If function gets a static chain arg, store it in the stack frame.
6563 Do this first, so it gets the first stack slot offset. */
6564 if (current_function_needs_context)
6566 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6568 /* Delay copying static chain if it is not a register to avoid
6569 conflicts with regs used for parameters. */
6570 if (! SMALL_REGISTER_CLASSES
6571 || GET_CODE (static_chain_incoming_rtx) == REG)
6572 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6575 /* If the parameters of this function need cleaning up, get a label
6576 for the beginning of the code which executes those cleanups. This must
6577 be done before doing anything with return_label. */
6578 if (parms_have_cleanups)
6579 cleanup_label = gen_label_rtx ();
6583 /* Make the label for return statements to jump to. Do not special
6584 case machines with special return instructions -- they will be
6585 handled later during jump, ifcvt, or epilogue creation. */
6586 return_label = gen_label_rtx ();
6588 /* Initialize rtx used to return the value. */
6589 /* Do this before assign_parms so that we copy the struct value address
6590 before any library calls that assign parms might generate. */
6592 /* Decide whether to return the value in memory or in a register. */
6593 if (aggregate_value_p (DECL_RESULT (subr), subr))
6595 /* Returning something that won't go in a register. */
6596 rtx value_address = 0;
6598 #ifdef PCC_STATIC_STRUCT_RETURN
6599 if (current_function_returns_pcc_struct)
6601 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6602 value_address = assemble_static_space (size);
6607 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
6608 /* Expect to be passed the address of a place to store the value.
6609 If it is passed as an argument, assign_parms will take care of
6613 value_address = gen_reg_rtx (Pmode);
6614 emit_move_insn (value_address, sv);
6619 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6620 set_mem_attributes (x, DECL_RESULT (subr), 1);
6621 SET_DECL_RTL (DECL_RESULT (subr), x);
6624 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6625 /* If return mode is void, this decl rtl should not be used. */
6626 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6629 /* Compute the return values into a pseudo reg, which we will copy
6630 into the true return register after the cleanups are done. */
6632 /* In order to figure out what mode to use for the pseudo, we
6633 figure out what the mode of the eventual return register will
6634 actually be, and use that. */
6636 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6639 /* Structures that are returned in registers are not aggregate_value_p,
6640 so we may see a PARALLEL or a REG. */
6641 if (REG_P (hard_reg))
6642 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6643 else if (GET_CODE (hard_reg) == PARALLEL)
6644 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6648 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6649 result to the real return register(s). */
6650 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6653 /* Initialize rtx for parameters and local variables.
6654 In some cases this requires emitting insns. */
6656 assign_parms (subr);
6658 /* Copy the static chain now if it wasn't a register. The delay is to
6659 avoid conflicts with the parameter passing registers. */
6661 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6662 if (GET_CODE (static_chain_incoming_rtx) != REG)
6663 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6665 /* The following was moved from init_function_start.
6666 The move is supposed to make sdb output more accurate. */
6667 /* Indicate the beginning of the function body,
6668 as opposed to parm setup. */
6669 emit_note (NOTE_INSN_FUNCTION_BEG);
6671 if (GET_CODE (get_last_insn ()) != NOTE)
6672 emit_note (NOTE_INSN_DELETED);
6673 parm_birth_insn = get_last_insn ();
6675 context_display = 0;
6676 if (current_function_needs_context)
6678 /* Fetch static chain values for containing functions. */
6679 tem = decl_function_context (current_function_decl);
6680 /* Copy the static chain pointer into a pseudo. If we have
6681 small register classes, copy the value from memory if
6682 static_chain_incoming_rtx is a REG. */
6685 /* If the static chain originally came in a register, put it back
6686 there, then move it out in the next insn. The reason for
6687 this peculiar code is to satisfy function integration. */
6688 if (SMALL_REGISTER_CLASSES
6689 && GET_CODE (static_chain_incoming_rtx) == REG)
6690 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6691 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6696 tree rtlexp = make_node (RTL_EXPR);
6698 RTL_EXPR_RTL (rtlexp) = last_ptr;
6699 context_display = tree_cons (tem, rtlexp, context_display);
6700 tem = decl_function_context (tem);
6703 /* Chain thru stack frames, assuming pointer to next lexical frame
6704 is found at the place we always store it. */
6705 #ifdef FRAME_GROWS_DOWNWARD
6706 last_ptr = plus_constant (last_ptr,
6707 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6709 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6710 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6711 last_ptr = copy_to_reg (last_ptr);
6713 /* If we are not optimizing, ensure that we know that this
6714 piece of context is live over the entire function. */
6716 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6721 if (current_function_instrument_entry_exit)
6723 rtx fun = DECL_RTL (current_function_decl);
6724 if (GET_CODE (fun) == MEM)
6725 fun = XEXP (fun, 0);
6728 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6730 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6732 hard_frame_pointer_rtx),
6736 if (current_function_profile)
6739 PROFILE_HOOK (current_function_funcdef_no);
6743 /* After the display initializations is where the tail-recursion label
6744 should go, if we end up needing one. Ensure we have a NOTE here
6745 since some things (like trampolines) get placed before this. */
6746 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
6748 /* Evaluate now the sizes of any types declared among the arguments. */
6749 expand_pending_sizes (nreverse (get_pending_sizes ()));
6751 /* Make sure there is a line number after the function entry setup code. */
6752 force_next_line_note ();
6755 /* Undo the effects of init_dummy_function_start. */
6757 expand_dummy_function_end (void)
6759 /* End any sequences that failed to be closed due to syntax errors. */
6760 while (in_sequence_p ())
6763 /* Outside function body, can't compute type's actual size
6764 until next function's body starts. */
6766 free_after_parsing (cfun);
6767 free_after_compilation (cfun);
6771 /* Call DOIT for each hard register used as a return value from
6772 the current function. */
6775 diddle_return_value (void (*doit) (rtx, void *), void *arg)
6777 rtx outgoing = current_function_return_rtx;
6782 if (GET_CODE (outgoing) == REG)
6783 (*doit) (outgoing, arg);
6784 else if (GET_CODE (outgoing) == PARALLEL)
6788 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6790 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6792 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6799 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6801 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6805 clobber_return_register (void)
6807 diddle_return_value (do_clobber_return_reg, NULL);
6809 /* In case we do use pseudo to return value, clobber it too. */
6810 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6812 tree decl_result = DECL_RESULT (current_function_decl);
6813 rtx decl_rtl = DECL_RTL (decl_result);
6814 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6816 do_clobber_return_reg (decl_rtl, NULL);
6822 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6824 emit_insn (gen_rtx_USE (VOIDmode, reg));
6828 use_return_register (void)
6830 diddle_return_value (do_use_return_reg, NULL);
6833 static GTY(()) rtx initial_trampoline;
6835 /* Generate RTL for the end of the current function. */
6838 expand_function_end (void)
6843 finish_expr_for_function ();
6845 /* If arg_pointer_save_area was referenced only from a nested
6846 function, we will not have initialized it yet. Do that now. */
6847 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6848 get_arg_pointer_save_area (cfun);
6850 #ifdef NON_SAVING_SETJMP
6851 /* Don't put any variables in registers if we call setjmp
6852 on a machine that fails to restore the registers. */
6853 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6855 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6856 setjmp_protect (DECL_INITIAL (current_function_decl));
6858 setjmp_protect_args ();
6862 /* Initialize any trampolines required by this function. */
6863 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6865 tree function = TREE_PURPOSE (link);
6866 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6867 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6868 #ifdef TRAMPOLINE_TEMPLATE
6873 #ifdef TRAMPOLINE_TEMPLATE
6874 /* First make sure this compilation has a template for
6875 initializing trampolines. */
6876 if (initial_trampoline == 0)
6879 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6880 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6884 /* Generate insns to initialize the trampoline. */
6886 tramp = round_trampoline_addr (XEXP (tramp, 0));
6887 #ifdef TRAMPOLINE_TEMPLATE
6888 blktramp = replace_equiv_address (initial_trampoline, tramp);
6889 emit_block_move (blktramp, initial_trampoline,
6890 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6892 trampolines_created = 1;
6893 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6897 /* Put those insns at entry to the containing function (this one). */
6898 emit_insn_before (seq, tail_recursion_reentry);
6901 /* If we are doing stack checking and this function makes calls,
6902 do a stack probe at the start of the function to ensure we have enough
6903 space for another stack frame. */
6904 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6908 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6909 if (GET_CODE (insn) == CALL_INSN)
6912 probe_stack_range (STACK_CHECK_PROTECT,
6913 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6916 emit_insn_before (seq, tail_recursion_reentry);
6921 /* Possibly warn about unused parameters. */
6922 if (warn_unused_parameter)
6926 for (decl = DECL_ARGUMENTS (current_function_decl);
6927 decl; decl = TREE_CHAIN (decl))
6928 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6929 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6930 warning ("%Junused parameter '%D'", decl, decl);
6933 /* Delete handlers for nonlocal gotos if nothing uses them. */
6934 if (nonlocal_goto_handler_slots != 0
6935 && ! current_function_has_nonlocal_label)
6938 /* End any sequences that failed to be closed due to syntax errors. */
6939 while (in_sequence_p ())
6942 /* Outside function body, can't compute type's actual size
6943 until next function's body starts. */
6944 immediate_size_expand--;
6946 clear_pending_stack_adjust ();
6947 do_pending_stack_adjust ();
6949 /* Mark the end of the function body.
6950 If control reaches this insn, the function can drop through
6951 without returning a value. */
6952 emit_note (NOTE_INSN_FUNCTION_END);
6954 /* Must mark the last line number note in the function, so that the test
6955 coverage code can avoid counting the last line twice. This just tells
6956 the code to ignore the immediately following line note, since there
6957 already exists a copy of this note somewhere above. This line number
6958 note is still needed for debugging though, so we can't delete it. */
6959 if (flag_test_coverage)
6960 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
6962 /* Output a linenumber for the end of the function.
6963 SDB depends on this. */
6964 force_next_line_note ();
6965 emit_line_note (input_location);
6967 /* Before the return label (if any), clobber the return
6968 registers so that they are not propagated live to the rest of
6969 the function. This can only happen with functions that drop
6970 through; if there had been a return statement, there would
6971 have either been a return rtx, or a jump to the return label.
6973 We delay actual code generation after the current_function_value_rtx
6975 clobber_after = get_last_insn ();
6977 /* Output the label for the actual return from the function,
6978 if one is expected. This happens either because a function epilogue
6979 is used instead of a return instruction, or because a return was done
6980 with a goto in order to run local cleanups, or because of pcc-style
6981 structure returning. */
6983 emit_label (return_label);
6985 if (current_function_instrument_entry_exit)
6987 rtx fun = DECL_RTL (current_function_decl);
6988 if (GET_CODE (fun) == MEM)
6989 fun = XEXP (fun, 0);
6992 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6994 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6996 hard_frame_pointer_rtx),
7000 /* Let except.c know where it should emit the call to unregister
7001 the function context for sjlj exceptions. */
7002 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
7003 sjlj_emit_function_exit_after (get_last_insn ());
7005 /* If we had calls to alloca, and this machine needs
7006 an accurate stack pointer to exit the function,
7007 insert some code to save and restore the stack pointer. */
7008 #ifdef EXIT_IGNORE_STACK
7009 if (! EXIT_IGNORE_STACK)
7011 if (current_function_calls_alloca)
7015 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
7016 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
7019 /* If scalar return value was computed in a pseudo-reg, or was a named
7020 return value that got dumped to the stack, copy that to the hard
7022 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
7024 tree decl_result = DECL_RESULT (current_function_decl);
7025 rtx decl_rtl = DECL_RTL (decl_result);
7027 if (REG_P (decl_rtl)
7028 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
7029 : DECL_REGISTER (decl_result))
7031 rtx real_decl_rtl = current_function_return_rtx;
7033 /* This should be set in assign_parms. */
7034 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
7037 /* If this is a BLKmode structure being returned in registers,
7038 then use the mode computed in expand_return. Note that if
7039 decl_rtl is memory, then its mode may have been changed,
7040 but that current_function_return_rtx has not. */
7041 if (GET_MODE (real_decl_rtl) == BLKmode)
7042 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
7044 /* If a named return value dumped decl_return to memory, then
7045 we may need to re-do the PROMOTE_MODE signed/unsigned
7047 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
7049 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
7051 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
7052 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7055 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7057 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7059 /* If expand_function_start has created a PARALLEL for decl_rtl,
7060 move the result to the real return registers. Otherwise, do
7061 a group load from decl_rtl for a named return. */
7062 if (GET_CODE (decl_rtl) == PARALLEL)
7063 emit_group_move (real_decl_rtl, decl_rtl);
7065 emit_group_load (real_decl_rtl, decl_rtl,
7066 TREE_TYPE (decl_result),
7067 int_size_in_bytes (TREE_TYPE (decl_result)));
7070 emit_move_insn (real_decl_rtl, decl_rtl);
7074 /* If returning a structure, arrange to return the address of the value
7075 in a place where debuggers expect to find it.
7077 If returning a structure PCC style,
7078 the caller also depends on this value.
7079 And current_function_returns_pcc_struct is not necessarily set. */
7080 if (current_function_returns_struct
7081 || current_function_returns_pcc_struct)
7084 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7085 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7086 #ifdef FUNCTION_OUTGOING_VALUE
7088 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7089 current_function_decl);
7092 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7095 /* Mark this as a function return value so integrate will delete the
7096 assignment and USE below when inlining this function. */
7097 REG_FUNCTION_VALUE_P (outgoing) = 1;
7099 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7100 value_address = convert_memory_address (GET_MODE (outgoing),
7103 emit_move_insn (outgoing, value_address);
7105 /* Show return register used to hold result (in this case the address
7107 current_function_return_rtx = outgoing;
7110 /* If this is an implementation of throw, do what's necessary to
7111 communicate between __builtin_eh_return and the epilogue. */
7112 expand_eh_return ();
7114 /* Emit the actual code to clobber return register. */
7119 clobber_return_register ();
7123 after = emit_insn_after (seq, clobber_after);
7125 if (clobber_after != after)
7126 cfun->x_clobber_return_insn = after;
7129 /* ??? This should no longer be necessary since stupid is no longer with
7130 us, but there are some parts of the compiler (eg reload_combine, and
7131 sh mach_dep_reorg) that still try and compute their own lifetime info
7132 instead of using the general framework. */
7133 use_return_register ();
7135 /* Fix up any gotos that jumped out to the outermost
7136 binding level of the function.
7137 Must follow emitting RETURN_LABEL. */
7139 /* If you have any cleanups to do at this point,
7140 and they need to create temporary variables,
7141 then you will lose. */
7142 expand_fixups (get_insns ());
7146 get_arg_pointer_save_area (struct function *f)
7148 rtx ret = f->x_arg_pointer_save_area;
7152 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7153 f->x_arg_pointer_save_area = ret;
7156 if (f == cfun && ! f->arg_pointer_save_area_init)
7160 /* Save the arg pointer at the beginning of the function. The
7161 generated stack slot may not be a valid memory address, so we
7162 have to check it and fix it if necessary. */
7164 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7168 push_topmost_sequence ();
7169 emit_insn_after (seq, get_insns ());
7170 pop_topmost_sequence ();
7176 /* Extend a vector that records the INSN_UIDs of INSNS
7177 (a list of one or more insns). */
7180 record_insns (rtx insns, varray_type *vecp)
7187 while (tmp != NULL_RTX)
7190 tmp = NEXT_INSN (tmp);
7193 i = VARRAY_SIZE (*vecp);
7194 VARRAY_GROW (*vecp, i + len);
7196 while (tmp != NULL_RTX)
7198 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7200 tmp = NEXT_INSN (tmp);
7204 /* Set the specified locator to the insn chain. */
7206 set_insn_locators (rtx insn, int loc)
7208 while (insn != NULL_RTX)
7211 INSN_LOCATOR (insn) = loc;
7212 insn = NEXT_INSN (insn);
7216 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7217 be running after reorg, SEQUENCE rtl is possible. */
7220 contains (rtx insn, varray_type vec)
7224 if (GET_CODE (insn) == INSN
7225 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7228 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7229 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7230 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7236 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7237 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7244 prologue_epilogue_contains (rtx insn)
7246 if (contains (insn, prologue))
7248 if (contains (insn, epilogue))
7254 sibcall_epilogue_contains (rtx insn)
7256 if (sibcall_epilogue)
7257 return contains (insn, sibcall_epilogue);
7262 /* Insert gen_return at the end of block BB. This also means updating
7263 block_for_insn appropriately. */
7266 emit_return_into_block (basic_block bb, rtx line_note)
7268 emit_jump_insn_after (gen_return (), bb->end);
7270 emit_note_copy_after (line_note, PREV_INSN (bb->end));
7272 #endif /* HAVE_return */
7274 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7276 /* These functions convert the epilogue into a variant that does not modify the
7277 stack pointer. This is used in cases where a function returns an object
7278 whose size is not known until it is computed. The called function leaves the
7279 object on the stack, leaves the stack depressed, and returns a pointer to
7282 What we need to do is track all modifications and references to the stack
7283 pointer, deleting the modifications and changing the references to point to
7284 the location the stack pointer would have pointed to had the modifications
7287 These functions need to be portable so we need to make as few assumptions
7288 about the epilogue as we can. However, the epilogue basically contains
7289 three things: instructions to reset the stack pointer, instructions to
7290 reload registers, possibly including the frame pointer, and an
7291 instruction to return to the caller.
7293 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7294 We also make no attempt to validate the insns we make since if they are
7295 invalid, we probably can't do anything valid. The intent is that these
7296 routines get "smarter" as more and more machines start to use them and
7297 they try operating on different epilogues.
7299 We use the following structure to track what the part of the epilogue that
7300 we've already processed has done. We keep two copies of the SP equivalence,
7301 one for use during the insn we are processing and one for use in the next
7302 insn. The difference is because one part of a PARALLEL may adjust SP
7303 and the other may use it. */
7307 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7308 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7309 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7310 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7311 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7312 should be set to once we no longer need
7314 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences
7318 static void handle_epilogue_set (rtx, struct epi_info *);
7319 static void update_epilogue_consts PARAMS ((rtx, rtx, void *));
7320 static void emit_equiv_load (struct epi_info *);
7322 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7323 no modifications to the stack pointer. Return the new list of insns. */
7326 keep_stack_depressed (rtx insns)
7329 struct epi_info info;
7332 /* If the epilogue is just a single instruction, it must be OK as is. */
7333 if (NEXT_INSN (insns) == NULL_RTX)
7336 /* Otherwise, start a sequence, initialize the information we have, and
7337 process all the insns we were given. */
7340 info.sp_equiv_reg = stack_pointer_rtx;
7342 info.equiv_reg_src = 0;
7344 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
7345 info.const_equiv[j] = 0;
7349 while (insn != NULL_RTX)
7351 next = NEXT_INSN (insn);
7360 /* If this insn references the register that SP is equivalent to and
7361 we have a pending load to that register, we must force out the load
7362 first and then indicate we no longer know what SP's equivalent is. */
7363 if (info.equiv_reg_src != 0
7364 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7366 emit_equiv_load (&info);
7367 info.sp_equiv_reg = 0;
7370 info.new_sp_equiv_reg = info.sp_equiv_reg;
7371 info.new_sp_offset = info.sp_offset;
7373 /* If this is a (RETURN) and the return address is on the stack,
7374 update the address and change to an indirect jump. */
7375 if (GET_CODE (PATTERN (insn)) == RETURN
7376 || (GET_CODE (PATTERN (insn)) == PARALLEL
7377 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7379 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7381 HOST_WIDE_INT offset = 0;
7382 rtx jump_insn, jump_set;
7384 /* If the return address is in a register, we can emit the insn
7385 unchanged. Otherwise, it must be a MEM and we see what the
7386 base register and offset are. In any case, we have to emit any
7387 pending load to the equivalent reg of SP, if any. */
7388 if (GET_CODE (retaddr) == REG)
7390 emit_equiv_load (&info);
7395 else if (GET_CODE (retaddr) == MEM
7396 && GET_CODE (XEXP (retaddr, 0)) == REG)
7397 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7398 else if (GET_CODE (retaddr) == MEM
7399 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7400 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7401 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7403 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7404 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7409 /* If the base of the location containing the return pointer
7410 is SP, we must update it with the replacement address. Otherwise,
7411 just build the necessary MEM. */
7412 retaddr = plus_constant (base, offset);
7413 if (base == stack_pointer_rtx)
7414 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7415 plus_constant (info.sp_equiv_reg,
7418 retaddr = gen_rtx_MEM (Pmode, retaddr);
7420 /* If there is a pending load to the equivalent register for SP
7421 and we reference that register, we must load our address into
7422 a scratch register and then do that load. */
7423 if (info.equiv_reg_src
7424 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7429 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7430 if (HARD_REGNO_MODE_OK (regno, Pmode)
7431 && !fixed_regs[regno]
7432 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7433 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7435 && !refers_to_regno_p (regno,
7436 regno + HARD_REGNO_NREGS (regno,
7438 info.equiv_reg_src, NULL)
7439 && info.const_equiv[regno] == 0)
7442 if (regno == FIRST_PSEUDO_REGISTER)
7445 reg = gen_rtx_REG (Pmode, regno);
7446 emit_move_insn (reg, retaddr);
7450 emit_equiv_load (&info);
7451 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7453 /* Show the SET in the above insn is a RETURN. */
7454 jump_set = single_set (jump_insn);
7458 SET_IS_RETURN_P (jump_set) = 1;
7461 /* If SP is not mentioned in the pattern and its equivalent register, if
7462 any, is not modified, just emit it. Otherwise, if neither is set,
7463 replace the reference to SP and emit the insn. If none of those are
7464 true, handle each SET individually. */
7465 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7466 && (info.sp_equiv_reg == stack_pointer_rtx
7467 || !reg_set_p (info.sp_equiv_reg, insn)))
7469 else if (! reg_set_p (stack_pointer_rtx, insn)
7470 && (info.sp_equiv_reg == stack_pointer_rtx
7471 || !reg_set_p (info.sp_equiv_reg, insn)))
7473 if (! validate_replace_rtx (stack_pointer_rtx,
7474 plus_constant (info.sp_equiv_reg,
7481 else if (GET_CODE (PATTERN (insn)) == SET)
7482 handle_epilogue_set (PATTERN (insn), &info);
7483 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7485 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7486 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7487 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7492 info.sp_equiv_reg = info.new_sp_equiv_reg;
7493 info.sp_offset = info.new_sp_offset;
7495 /* Now update any constants this insn sets. */
7496 note_stores (PATTERN (insn), update_epilogue_consts, &info);
7500 insns = get_insns ();
7505 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7506 structure that contains information about what we've seen so far. We
7507 process this SET by either updating that data or by emitting one or
7511 handle_epilogue_set (rtx set, struct epi_info *p)
7513 /* First handle the case where we are setting SP. Record what it is being
7514 set from. If unknown, abort. */
7515 if (reg_set_p (stack_pointer_rtx, set))
7517 if (SET_DEST (set) != stack_pointer_rtx)
7520 if (GET_CODE (SET_SRC (set)) == PLUS)
7522 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7523 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7524 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7525 else if (GET_CODE (XEXP (SET_SRC (set), 1)) == REG
7526 && REGNO (XEXP (SET_SRC (set), 1)) < FIRST_PSEUDO_REGISTER
7527 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))] != 0)
7529 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
7534 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7536 /* If we are adjusting SP, we adjust from the old data. */
7537 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7539 p->new_sp_equiv_reg = p->sp_equiv_reg;
7540 p->new_sp_offset += p->sp_offset;
7543 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7549 /* Next handle the case where we are setting SP's equivalent register.
7550 If we already have a value to set it to, abort. We could update, but
7551 there seems little point in handling that case. Note that we have
7552 to allow for the case where we are setting the register set in
7553 the previous part of a PARALLEL inside a single insn. But use the
7554 old offset for any updates within this insn. We must allow for the case
7555 where the register is being set in a different (usually wider) mode than
7557 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7559 if (p->equiv_reg_src != 0
7560 || GET_CODE (p->new_sp_equiv_reg) != REG
7561 || GET_CODE (SET_DEST (set)) != REG
7562 || GET_MODE_BITSIZE (GET_MODE (SET_DEST (set))) > BITS_PER_WORD
7563 || REGNO (p->new_sp_equiv_reg) != REGNO (SET_DEST (set)))
7567 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7568 plus_constant (p->sp_equiv_reg,
7572 /* Otherwise, replace any references to SP in the insn to its new value
7573 and emit the insn. */
7576 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7577 plus_constant (p->sp_equiv_reg,
7579 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7580 plus_constant (p->sp_equiv_reg,
7586 /* Update the tracking information for registers set to constants. */
7589 update_epilogue_consts (rtx dest, rtx x, void *data)
7591 struct epi_info *p = (struct epi_info *) data;
7593 if (GET_CODE (dest) != REG || REGNO (dest) >= FIRST_PSEUDO_REGISTER)
7595 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x))
7596 || GET_CODE (SET_SRC (x)) != CONST_INT)
7597 p->const_equiv[REGNO (dest)] = 0;
7599 p->const_equiv[REGNO (dest)] = SET_SRC (x);
7602 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7605 emit_equiv_load (struct epi_info *p)
7607 if (p->equiv_reg_src != 0)
7609 rtx dest = p->sp_equiv_reg;
7611 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest))
7612 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src),
7613 REGNO (p->sp_equiv_reg));
7615 emit_move_insn (dest, p->equiv_reg_src);
7616 p->equiv_reg_src = 0;
7621 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7622 this into place with notes indicating where the prologue ends and where
7623 the epilogue begins. Update the basic block information when possible. */
7626 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
7630 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7633 #ifdef HAVE_prologue
7634 rtx prologue_end = NULL_RTX;
7636 #if defined (HAVE_epilogue) || defined(HAVE_return)
7637 rtx epilogue_end = NULL_RTX;
7640 #ifdef HAVE_prologue
7644 seq = gen_prologue ();
7647 /* Retain a map of the prologue insns. */
7648 record_insns (seq, &prologue);
7649 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
7653 set_insn_locators (seq, prologue_locator);
7655 /* Can't deal with multiple successors of the entry block
7656 at the moment. Function should always have at least one
7658 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7661 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7666 /* If the exit block has no non-fake predecessors, we don't need
7668 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7669 if ((e->flags & EDGE_FAKE) == 0)
7675 if (optimize && HAVE_return)
7677 /* If we're allowed to generate a simple return instruction,
7678 then by definition we don't need a full epilogue. Examine
7679 the block that falls through to EXIT. If it does not
7680 contain any code, examine its predecessors and try to
7681 emit (conditional) return instructions. */
7687 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7688 if (e->flags & EDGE_FALLTHRU)
7694 /* Verify that there are no active instructions in the last block. */
7696 while (label && GET_CODE (label) != CODE_LABEL)
7698 if (active_insn_p (label))
7700 label = PREV_INSN (label);
7703 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7705 rtx epilogue_line_note = NULL_RTX;
7707 /* Locate the line number associated with the closing brace,
7708 if we can find one. */
7709 for (seq = get_last_insn ();
7710 seq && ! active_insn_p (seq);
7711 seq = PREV_INSN (seq))
7712 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7714 epilogue_line_note = seq;
7718 for (e = last->pred; e; e = e_next)
7720 basic_block bb = e->src;
7723 e_next = e->pred_next;
7724 if (bb == ENTRY_BLOCK_PTR)
7728 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7731 /* If we have an unconditional jump, we can replace that
7732 with a simple return instruction. */
7733 if (simplejump_p (jump))
7735 emit_return_into_block (bb, epilogue_line_note);
7739 /* If we have a conditional jump, we can try to replace
7740 that with a conditional return instruction. */
7741 else if (condjump_p (jump))
7743 if (! redirect_jump (jump, 0, 0))
7746 /* If this block has only one successor, it both jumps
7747 and falls through to the fallthru block, so we can't
7749 if (bb->succ->succ_next == NULL)
7755 /* Fix up the CFG for the successful change we just made. */
7756 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7759 /* Emit a return insn for the exit fallthru block. Whether
7760 this is still reachable will be determined later. */
7762 emit_barrier_after (last->end);
7763 emit_return_into_block (last, epilogue_line_note);
7764 epilogue_end = last->end;
7765 last->succ->flags &= ~EDGE_FALLTHRU;
7770 #ifdef HAVE_epilogue
7773 /* Find the edge that falls through to EXIT. Other edges may exist
7774 due to RETURN instructions, but those don't need epilogues.
7775 There really shouldn't be a mixture -- either all should have
7776 been converted or none, however... */
7778 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7779 if (e->flags & EDGE_FALLTHRU)
7785 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
7787 seq = gen_epilogue ();
7789 #ifdef INCOMING_RETURN_ADDR_RTX
7790 /* If this function returns with the stack depressed and we can support
7791 it, massage the epilogue to actually do that. */
7792 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7793 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7794 seq = keep_stack_depressed (seq);
7797 emit_jump_insn (seq);
7799 /* Retain a map of the epilogue insns. */
7800 record_insns (seq, &epilogue);
7801 set_insn_locators (seq, epilogue_locator);
7806 insert_insn_on_edge (seq, e);
7813 commit_edge_insertions ();
7815 #ifdef HAVE_sibcall_epilogue
7816 /* Emit sibling epilogues before any sibling call sites. */
7817 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7819 basic_block bb = e->src;
7824 if (GET_CODE (insn) != CALL_INSN
7825 || ! SIBLING_CALL_P (insn))
7829 emit_insn (gen_sibcall_epilogue ());
7833 /* Retain a map of the epilogue insns. Used in life analysis to
7834 avoid getting rid of sibcall epilogue insns. Do this before we
7835 actually emit the sequence. */
7836 record_insns (seq, &sibcall_epilogue);
7837 set_insn_locators (seq, epilogue_locator);
7839 i = PREV_INSN (insn);
7840 newinsn = emit_insn_before (seq, insn);
7844 #ifdef HAVE_prologue
7849 /* GDB handles `break f' by setting a breakpoint on the first
7850 line note after the prologue. Which means (1) that if
7851 there are line number notes before where we inserted the
7852 prologue we should move them, and (2) we should generate a
7853 note before the end of the first basic block, if there isn't
7856 ??? This behavior is completely broken when dealing with
7857 multiple entry functions. We simply place the note always
7858 into first basic block and let alternate entry points
7862 for (insn = prologue_end; insn; insn = prev)
7864 prev = PREV_INSN (insn);
7865 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7867 /* Note that we cannot reorder the first insn in the
7868 chain, since rest_of_compilation relies on that
7869 remaining constant. */
7872 reorder_insns (insn, insn, prologue_end);
7876 /* Find the last line number note in the first block. */
7877 for (insn = ENTRY_BLOCK_PTR->next_bb->end;
7878 insn != prologue_end && insn;
7879 insn = PREV_INSN (insn))
7880 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7883 /* If we didn't find one, make a copy of the first line number
7887 for (insn = next_active_insn (prologue_end);
7889 insn = PREV_INSN (insn))
7890 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7892 emit_note_copy_after (insn, prologue_end);
7898 #ifdef HAVE_epilogue
7903 /* Similarly, move any line notes that appear after the epilogue.
7904 There is no need, however, to be quite so anal about the existence
7906 for (insn = epilogue_end; insn; insn = next)
7908 next = NEXT_INSN (insn);
7909 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7910 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7916 /* Reposition the prologue-end and epilogue-begin notes after instruction
7917 scheduling and delayed branch scheduling. */
7920 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
7922 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7923 rtx insn, last, note;
7926 if ((len = VARRAY_SIZE (prologue)) > 0)
7930 /* Scan from the beginning until we reach the last prologue insn.
7931 We apparently can't depend on basic_block_{head,end} after
7933 for (insn = f; insn; insn = NEXT_INSN (insn))
7935 if (GET_CODE (insn) == NOTE)
7937 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7940 else if (contains (insn, prologue))
7950 /* Find the prologue-end note if we haven't already, and
7951 move it to just after the last prologue insn. */
7954 for (note = last; (note = NEXT_INSN (note));)
7955 if (GET_CODE (note) == NOTE
7956 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7960 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7961 if (GET_CODE (last) == CODE_LABEL)
7962 last = NEXT_INSN (last);
7963 reorder_insns (note, note, last);
7967 if ((len = VARRAY_SIZE (epilogue)) > 0)
7971 /* Scan from the end until we reach the first epilogue insn.
7972 We apparently can't depend on basic_block_{head,end} after
7974 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7976 if (GET_CODE (insn) == NOTE)
7978 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7981 else if (contains (insn, epilogue))
7991 /* Find the epilogue-begin note if we haven't already, and
7992 move it to just before the first epilogue insn. */
7995 for (note = insn; (note = PREV_INSN (note));)
7996 if (GET_CODE (note) == NOTE
7997 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
8001 if (PREV_INSN (last) != note)
8002 reorder_insns (note, note, PREV_INSN (last));
8005 #endif /* HAVE_prologue or HAVE_epilogue */
8008 /* Called once, at initialization, to initialize function.c. */
8011 init_function_once (void)
8013 VARRAY_INT_INIT (prologue, 0, "prologue");
8014 VARRAY_INT_INIT (epilogue, 0, "epilogue");
8015 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
8018 #include "gt-function.h"