1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
43 #include "coretypes.h"
54 #include "hard-reg-set.h"
55 #include "insn-config.h"
58 #include "basic-block.h"
63 #include "integrate.h"
64 #include "langhooks.h"
67 #ifndef TRAMPOLINE_ALIGNMENT
68 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
71 #ifndef LOCAL_ALIGNMENT
72 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
75 #ifndef STACK_ALIGNMENT_NEEDED
76 #define STACK_ALIGNMENT_NEEDED 1
79 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
81 /* Some systems use __main in a way incompatible with its use in gcc, in these
82 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
83 give the same symbol without quotes for an alternative entry point. You
84 must define both, or neither. */
86 #define NAME__MAIN "__main"
89 /* Round a value to the lowest integer less than it that is a multiple of
90 the required alignment. Avoid using division in case the value is
91 negative. Assume the alignment is a power of two. */
92 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
94 /* Similar, but round to the next highest integer that meets the
96 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
98 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
99 during rtl generation. If they are different register numbers, this is
100 always true. It may also be true if
101 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
102 generation. See fix_lexical_addr for details. */
104 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
105 #define NEED_SEPARATE_AP
108 /* Nonzero if function being compiled doesn't contain any calls
109 (ignoring the prologue and epilogue). This is set prior to
110 local register allocation and is valid for the remaining
112 int current_function_is_leaf;
114 /* Nonzero if function being compiled doesn't contain any instructions
115 that can throw an exception. This is set prior to final. */
117 int current_function_nothrow;
119 /* Nonzero if function being compiled doesn't modify the stack pointer
120 (ignoring the prologue and epilogue). This is only valid after
121 life_analysis has run. */
122 int current_function_sp_is_unchanging;
124 /* Nonzero if the function being compiled is a leaf function which only
125 uses leaf registers. This is valid after reload (specifically after
126 sched2) and is useful only if the port defines LEAF_REGISTERS. */
127 int current_function_uses_only_leaf_regs;
129 /* Nonzero once virtual register instantiation has been done.
130 assign_stack_local uses frame_pointer_rtx when this is nonzero.
131 calls.c:emit_library_call_value_1 uses it to set up
132 post-instantiation libcalls. */
133 int virtuals_instantiated;
135 /* Nonzero if at least one trampoline has been created. */
136 int trampolines_created;
138 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
139 static GTY(()) int funcdef_no;
141 /* These variables hold pointers to functions to create and destroy
142 target specific, per-function data structures. */
143 struct machine_function * (*init_machine_status) (void);
145 /* The FUNCTION_DECL for an inline function currently being expanded. */
146 tree inline_function_decl;
148 /* The currently compiled function. */
149 struct function *cfun = 0;
151 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
152 static GTY(()) varray_type prologue;
153 static GTY(()) varray_type epilogue;
155 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
157 static GTY(()) varray_type sibcall_epilogue;
159 /* In order to evaluate some expressions, such as function calls returning
160 structures in memory, we need to temporarily allocate stack locations.
161 We record each allocated temporary in the following structure.
163 Associated with each temporary slot is a nesting level. When we pop up
164 one level, all temporaries associated with the previous level are freed.
165 Normally, all temporaries are freed after the execution of the statement
166 in which they were created. However, if we are inside a ({...}) grouping,
167 the result may be in a temporary and hence must be preserved. If the
168 result could be in a temporary, we preserve it if we can determine which
169 one it is in. If we cannot determine which temporary may contain the
170 result, all temporaries are preserved. A temporary is preserved by
171 pretending it was allocated at the previous nesting level.
173 Automatic variables are also assigned temporary slots, at the nesting
174 level where they are defined. They are marked a "kept" so that
175 free_temp_slots will not free them. */
177 struct temp_slot GTY(())
179 /* Points to next temporary slot. */
180 struct temp_slot *next;
181 /* The rtx to used to reference the slot. */
183 /* The rtx used to represent the address if not the address of the
184 slot above. May be an EXPR_LIST if multiple addresses exist. */
186 /* The alignment (in bits) of the slot. */
188 /* The size, in units, of the slot. */
190 /* The type of the object in the slot, or zero if it doesn't correspond
191 to a type. We use this to determine whether a slot can be reused.
192 It can be reused if objects of the type of the new slot will always
193 conflict with objects of the type of the old slot. */
195 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
197 /* Nonzero if this temporary is currently in use. */
199 /* Nonzero if this temporary has its address taken. */
201 /* Nesting level at which this slot is being used. */
203 /* Nonzero if this should survive a call to free_temp_slots. */
205 /* The offset of the slot from the frame_pointer, including extra space
206 for alignment. This info is for combine_temp_slots. */
207 HOST_WIDE_INT base_offset;
208 /* The size of the slot, including extra space for alignment. This
209 info is for combine_temp_slots. */
210 HOST_WIDE_INT full_size;
213 /* This structure is used to record MEMs or pseudos used to replace VAR, any
214 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
215 maintain this list in case two operands of an insn were required to match;
216 in that case we must ensure we use the same replacement. */
218 struct fixup_replacement GTY(())
222 struct fixup_replacement *next;
225 struct insns_for_mem_entry
229 /* These are the INSNs which reference the MEM. */
233 /* Forward declarations. */
235 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int,
237 static struct temp_slot *find_temp_slot_from_address (rtx);
238 static void put_reg_into_stack (struct function *, rtx, tree, enum machine_mode,
239 enum machine_mode, int, unsigned int, int, htab_t);
240 static void schedule_fixup_var_refs (struct function *, rtx, tree, enum machine_mode,
242 static void fixup_var_refs (rtx, enum machine_mode, int, rtx, htab_t);
243 static struct fixup_replacement
244 *find_fixup_replacement (struct fixup_replacement **, rtx);
245 static void fixup_var_refs_insns (rtx, rtx, enum machine_mode, int, int, rtx);
246 static void fixup_var_refs_insns_with_hash (htab_t, rtx, enum machine_mode, int, rtx);
247 static void fixup_var_refs_insn (rtx, rtx, enum machine_mode, int, int, rtx);
248 static void fixup_var_refs_1 (rtx, enum machine_mode, rtx *, rtx,
249 struct fixup_replacement **, rtx);
250 static rtx fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
251 static rtx walk_fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
252 static rtx fixup_stack_1 (rtx, rtx);
253 static void optimize_bit_field (rtx, rtx, rtx *);
254 static void instantiate_decls (tree, int);
255 static void instantiate_decls_1 (tree, int);
256 static void instantiate_decl (rtx, HOST_WIDE_INT, int);
257 static rtx instantiate_new_reg (rtx, HOST_WIDE_INT *);
258 static int instantiate_virtual_regs_1 (rtx *, rtx, int);
259 static void delete_handlers (void);
260 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
261 static void pad_below (struct args_size *, enum machine_mode, tree);
262 static rtx round_trampoline_addr (rtx);
263 static rtx adjust_trampoline_addr (rtx);
264 static tree *identify_blocks_1 (rtx, tree *, tree *, tree *);
265 static void reorder_blocks_0 (tree);
266 static void reorder_blocks_1 (rtx, tree, varray_type *);
267 static void reorder_fix_fragments (tree);
268 static tree blocks_nreverse (tree);
269 static int all_blocks (tree, tree *);
270 static tree *get_block_vector (tree, int *);
271 extern tree debug_find_var_in_block_tree (tree, tree);
272 /* We always define `record_insns' even if it's not used so that we
273 can always export `prologue_epilogue_contains'. */
274 static void record_insns (rtx, varray_type *) ATTRIBUTE_UNUSED;
275 static int contains (rtx, varray_type);
277 static void emit_return_into_block (basic_block, rtx);
279 static void put_addressof_into_stack (rtx, htab_t);
280 static bool purge_addressof_1 (rtx *, rtx, int, int, int, htab_t);
281 static void purge_single_hard_subreg_set (rtx);
282 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
283 static rtx keep_stack_depressed (rtx);
285 static int is_addressof (rtx *, void *);
286 static hashval_t insns_for_mem_hash (const void *);
287 static int insns_for_mem_comp (const void *, const void *);
288 static int insns_for_mem_walk (rtx *, void *);
289 static void compute_insns_for_mem (rtx, rtx, htab_t);
290 static void prepare_function_start (tree);
291 static void do_clobber_return_reg (rtx, void *);
292 static void do_use_return_reg (rtx, void *);
293 static void instantiate_virtual_regs_lossage (rtx);
294 static tree split_complex_args (tree);
295 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
297 /* Pointer to chain of `struct function' for containing functions. */
298 struct function *outer_function_chain;
300 /* List of insns that were postponed by purge_addressof_1. */
301 static rtx postponed_insns;
303 /* Given a function decl for a containing function,
304 return the `struct function' for it. */
307 find_function_data (tree decl)
311 for (p = outer_function_chain; p; p = p->outer)
318 /* Save the current context for compilation of a nested function.
319 This is called from language-specific code. The caller should use
320 the enter_nested langhook to save any language-specific state,
321 since this function knows only about language-independent
325 push_function_context_to (tree context)
331 if (context == current_function_decl)
332 cfun->contains_functions = 1;
335 struct function *containing = find_function_data (context);
336 containing->contains_functions = 1;
341 init_dummy_function_start ();
344 p->outer = outer_function_chain;
345 outer_function_chain = p;
346 p->fixup_var_refs_queue = 0;
348 (*lang_hooks.function.enter_nested) (p);
354 push_function_context (void)
356 push_function_context_to (current_function_decl);
359 /* Restore the last saved context, at the end of a nested function.
360 This function is called from language-specific code. */
363 pop_function_context_from (tree context ATTRIBUTE_UNUSED)
365 struct function *p = outer_function_chain;
366 struct var_refs_queue *queue;
369 outer_function_chain = p->outer;
371 current_function_decl = p->decl;
374 restore_emit_status (p);
376 (*lang_hooks.function.leave_nested) (p);
378 /* Finish doing put_var_into_stack for any of our variables which became
379 addressable during the nested function. If only one entry has to be
380 fixed up, just do that one. Otherwise, first make a list of MEMs that
381 are not to be unshared. */
382 if (p->fixup_var_refs_queue == 0)
384 else if (p->fixup_var_refs_queue->next == 0)
385 fixup_var_refs (p->fixup_var_refs_queue->modified,
386 p->fixup_var_refs_queue->promoted_mode,
387 p->fixup_var_refs_queue->unsignedp,
388 p->fixup_var_refs_queue->modified, 0);
393 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
394 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
396 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
397 fixup_var_refs (queue->modified, queue->promoted_mode,
398 queue->unsignedp, list, 0);
402 p->fixup_var_refs_queue = 0;
404 /* Reset variables that have known state during rtx generation. */
405 rtx_equal_function_value_matters = 1;
406 virtuals_instantiated = 0;
407 generating_concat_p = 1;
411 pop_function_context (void)
413 pop_function_context_from (current_function_decl);
416 /* Clear out all parts of the state in F that can safely be discarded
417 after the function has been parsed, but not compiled, to let
418 garbage collection reclaim the memory. */
421 free_after_parsing (struct function *f)
423 /* f->expr->forced_labels is used by code generation. */
424 /* f->emit->regno_reg_rtx is used by code generation. */
425 /* f->varasm is used by code generation. */
426 /* f->eh->eh_return_stub_label is used by code generation. */
428 (*lang_hooks.function.final) (f);
432 /* Clear out all parts of the state in F that can safely be discarded
433 after the function has been compiled, to let garbage collection
434 reclaim the memory. */
437 free_after_compilation (struct function *f)
445 f->x_temp_slots = NULL;
446 f->arg_offset_rtx = NULL;
447 f->return_rtx = NULL;
448 f->internal_arg_pointer = NULL;
449 f->x_nonlocal_labels = NULL;
450 f->x_nonlocal_goto_handler_slots = NULL;
451 f->x_nonlocal_goto_handler_labels = NULL;
452 f->x_nonlocal_goto_stack_level = NULL;
453 f->x_cleanup_label = NULL;
454 f->x_return_label = NULL;
455 f->x_naked_return_label = NULL;
456 f->computed_goto_common_label = NULL;
457 f->computed_goto_common_reg = NULL;
458 f->x_save_expr_regs = NULL;
459 f->x_stack_slot_list = NULL;
460 f->x_rtl_expr_chain = NULL;
461 f->x_tail_recursion_label = NULL;
462 f->x_tail_recursion_reentry = NULL;
463 f->x_arg_pointer_save_area = NULL;
464 f->x_clobber_return_insn = NULL;
465 f->x_context_display = NULL;
466 f->x_trampoline_list = NULL;
467 f->x_parm_birth_insn = NULL;
468 f->x_last_parm_insn = NULL;
469 f->x_parm_reg_stack_loc = NULL;
470 f->fixup_var_refs_queue = NULL;
471 f->original_arg_vector = NULL;
472 f->original_decl_initial = NULL;
473 f->inl_last_parm_insn = NULL;
474 f->epilogue_delay_list = NULL;
477 /* Allocate fixed slots in the stack frame of the current function. */
479 /* Return size needed for stack frame based on slots so far allocated in
481 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
482 the caller may have to do that. */
485 get_func_frame_size (struct function *f)
487 #ifdef FRAME_GROWS_DOWNWARD
488 return -f->x_frame_offset;
490 return f->x_frame_offset;
494 /* Return size needed for stack frame based on slots so far allocated.
495 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
496 the caller may have to do that. */
498 get_frame_size (void)
500 return get_func_frame_size (cfun);
503 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
504 with machine mode MODE.
506 ALIGN controls the amount of alignment for the address of the slot:
507 0 means according to MODE,
508 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
509 positive specifies alignment boundary in bits.
511 We do not round to stack_boundary here.
513 FUNCTION specifies the function to allocate in. */
516 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
517 struct function *function)
520 int bigend_correction = 0;
522 int frame_off, frame_alignment, frame_phase;
529 alignment = BIGGEST_ALIGNMENT;
531 alignment = GET_MODE_ALIGNMENT (mode);
533 /* Allow the target to (possibly) increase the alignment of this
535 type = (*lang_hooks.types.type_for_mode) (mode, 0);
537 alignment = LOCAL_ALIGNMENT (type, alignment);
539 alignment /= BITS_PER_UNIT;
541 else if (align == -1)
543 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
544 size = CEIL_ROUND (size, alignment);
547 alignment = align / BITS_PER_UNIT;
549 #ifdef FRAME_GROWS_DOWNWARD
550 function->x_frame_offset -= size;
553 /* Ignore alignment we can't do with expected alignment of the boundary. */
554 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
555 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
557 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
558 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
560 /* Calculate how many bytes the start of local variables is off from
562 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
563 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
564 frame_phase = frame_off ? frame_alignment - frame_off : 0;
566 /* Round the frame offset to the specified alignment. The default is
567 to always honor requests to align the stack but a port may choose to
568 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
569 if (STACK_ALIGNMENT_NEEDED
573 /* We must be careful here, since FRAME_OFFSET might be negative and
574 division with a negative dividend isn't as well defined as we might
575 like. So we instead assume that ALIGNMENT is a power of two and
576 use logical operations which are unambiguous. */
577 #ifdef FRAME_GROWS_DOWNWARD
578 function->x_frame_offset
579 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
582 function->x_frame_offset
583 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
588 /* On a big-endian machine, if we are allocating more space than we will use,
589 use the least significant bytes of those that are allocated. */
590 if (BYTES_BIG_ENDIAN && mode != BLKmode)
591 bigend_correction = size - GET_MODE_SIZE (mode);
593 /* If we have already instantiated virtual registers, return the actual
594 address relative to the frame pointer. */
595 if (function == cfun && virtuals_instantiated)
596 addr = plus_constant (frame_pointer_rtx,
598 (frame_offset + bigend_correction
599 + STARTING_FRAME_OFFSET, Pmode));
601 addr = plus_constant (virtual_stack_vars_rtx,
603 (function->x_frame_offset + bigend_correction,
606 #ifndef FRAME_GROWS_DOWNWARD
607 function->x_frame_offset += size;
610 x = gen_rtx_MEM (mode, addr);
612 function->x_stack_slot_list
613 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
618 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
622 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
624 return assign_stack_local_1 (mode, size, align, cfun);
627 /* Allocate a temporary stack slot and record it for possible later
630 MODE is the machine mode to be given to the returned rtx.
632 SIZE is the size in units of the space required. We do no rounding here
633 since assign_stack_local will do any required rounding.
635 KEEP is 1 if this slot is to be retained after a call to
636 free_temp_slots. Automatic variables for a block are allocated
637 with this flag. KEEP is 2 if we allocate a longer term temporary,
638 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
639 if we are to allocate something at an inner level to be treated as
640 a variable in the block (e.g., a SAVE_EXPR).
642 TYPE is the type that will be used for the stack slot. */
645 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, int keep,
649 struct temp_slot *p, *best_p = 0;
652 /* If SIZE is -1 it means that somebody tried to allocate a temporary
653 of a variable size. */
658 align = BIGGEST_ALIGNMENT;
660 align = GET_MODE_ALIGNMENT (mode);
663 type = (*lang_hooks.types.type_for_mode) (mode, 0);
666 align = LOCAL_ALIGNMENT (type, align);
668 /* Try to find an available, already-allocated temporary of the proper
669 mode which meets the size and alignment requirements. Choose the
670 smallest one with the closest alignment. */
671 for (p = temp_slots; p; p = p->next)
672 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
674 && objects_must_conflict_p (p->type, type)
675 && (best_p == 0 || best_p->size > p->size
676 || (best_p->size == p->size && best_p->align > p->align)))
678 if (p->align == align && p->size == size)
686 /* Make our best, if any, the one to use. */
689 /* If there are enough aligned bytes left over, make them into a new
690 temp_slot so that the extra bytes don't get wasted. Do this only
691 for BLKmode slots, so that we can be sure of the alignment. */
692 if (GET_MODE (best_p->slot) == BLKmode)
694 int alignment = best_p->align / BITS_PER_UNIT;
695 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
697 if (best_p->size - rounded_size >= alignment)
699 p = ggc_alloc (sizeof (struct temp_slot));
700 p->in_use = p->addr_taken = 0;
701 p->size = best_p->size - rounded_size;
702 p->base_offset = best_p->base_offset + rounded_size;
703 p->full_size = best_p->full_size - rounded_size;
704 p->slot = gen_rtx_MEM (BLKmode,
705 plus_constant (XEXP (best_p->slot, 0),
707 p->align = best_p->align;
710 p->type = best_p->type;
711 p->next = temp_slots;
714 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
717 best_p->size = rounded_size;
718 best_p->full_size = rounded_size;
725 /* If we still didn't find one, make a new temporary. */
728 HOST_WIDE_INT frame_offset_old = frame_offset;
730 p = ggc_alloc (sizeof (struct temp_slot));
732 /* We are passing an explicit alignment request to assign_stack_local.
733 One side effect of that is assign_stack_local will not round SIZE
734 to ensure the frame offset remains suitably aligned.
736 So for requests which depended on the rounding of SIZE, we go ahead
737 and round it now. We also make sure ALIGNMENT is at least
738 BIGGEST_ALIGNMENT. */
739 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
741 p->slot = assign_stack_local (mode,
743 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
749 /* The following slot size computation is necessary because we don't
750 know the actual size of the temporary slot until assign_stack_local
751 has performed all the frame alignment and size rounding for the
752 requested temporary. Note that extra space added for alignment
753 can be either above or below this stack slot depending on which
754 way the frame grows. We include the extra space if and only if it
755 is above this slot. */
756 #ifdef FRAME_GROWS_DOWNWARD
757 p->size = frame_offset_old - frame_offset;
762 /* Now define the fields used by combine_temp_slots. */
763 #ifdef FRAME_GROWS_DOWNWARD
764 p->base_offset = frame_offset;
765 p->full_size = frame_offset_old - frame_offset;
767 p->base_offset = frame_offset_old;
768 p->full_size = frame_offset - frame_offset_old;
771 p->next = temp_slots;
777 p->rtl_expr = seq_rtl_expr;
782 p->level = target_temp_slot_level;
787 p->level = var_temp_slot_level;
792 p->level = temp_slot_level;
797 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
798 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
799 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
801 /* If we know the alias set for the memory that will be used, use
802 it. If there's no TYPE, then we don't know anything about the
803 alias set for the memory. */
804 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
805 set_mem_align (slot, align);
807 /* If a type is specified, set the relevant flags. */
810 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
811 && TYPE_READONLY (type));
812 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
813 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
819 /* Allocate a temporary stack slot and record it for possible later
820 reuse. First three arguments are same as in preceding function. */
823 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
825 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
828 /* Assign a temporary.
829 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
830 and so that should be used in error messages. In either case, we
831 allocate of the given type.
832 KEEP is as for assign_stack_temp.
833 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
834 it is 0 if a register is OK.
835 DONT_PROMOTE is 1 if we should not promote values in register
839 assign_temp (tree type_or_decl, int keep, int memory_required,
840 int dont_promote ATTRIBUTE_UNUSED)
843 enum machine_mode mode;
844 #ifndef PROMOTE_FOR_CALL_ONLY
848 if (DECL_P (type_or_decl))
849 decl = type_or_decl, type = TREE_TYPE (decl);
851 decl = NULL, type = type_or_decl;
853 mode = TYPE_MODE (type);
854 #ifndef PROMOTE_FOR_CALL_ONLY
855 unsignedp = TREE_UNSIGNED (type);
858 if (mode == BLKmode || memory_required)
860 HOST_WIDE_INT size = int_size_in_bytes (type);
863 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
864 problems with allocating the stack space. */
868 /* Unfortunately, we don't yet know how to allocate variable-sized
869 temporaries. However, sometimes we have a fixed upper limit on
870 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
871 instead. This is the case for Chill variable-sized strings. */
872 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
873 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
874 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
875 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
877 /* The size of the temporary may be too large to fit into an integer. */
878 /* ??? Not sure this should happen except for user silliness, so limit
879 this to things that aren't compiler-generated temporaries. The
880 rest of the time we'll abort in assign_stack_temp_for_type. */
881 if (decl && size == -1
882 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
884 error ("%Jsize of variable '%D' is too large", decl, decl);
888 tmp = assign_stack_temp_for_type (mode, size, keep, type);
892 #ifndef PROMOTE_FOR_CALL_ONLY
894 mode = promote_mode (type, mode, &unsignedp, 0);
897 return gen_reg_rtx (mode);
900 /* Combine temporary stack slots which are adjacent on the stack.
902 This allows for better use of already allocated stack space. This is only
903 done for BLKmode slots because we can be sure that we won't have alignment
904 problems in this case. */
907 combine_temp_slots (void)
909 struct temp_slot *p, *q;
910 struct temp_slot *prev_p, *prev_q;
913 /* We can't combine slots, because the information about which slot
914 is in which alias set will be lost. */
915 if (flag_strict_aliasing)
918 /* If there are a lot of temp slots, don't do anything unless
919 high levels of optimization. */
920 if (! flag_expensive_optimizations)
921 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
922 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
925 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
929 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
930 for (q = p->next, prev_q = p; q; q = prev_q->next)
933 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
935 if (p->base_offset + p->full_size == q->base_offset)
937 /* Q comes after P; combine Q into P. */
939 p->full_size += q->full_size;
942 else if (q->base_offset + q->full_size == p->base_offset)
944 /* P comes after Q; combine P into Q. */
946 q->full_size += p->full_size;
951 /* Either delete Q or advance past it. */
953 prev_q->next = q->next;
957 /* Either delete P or advance past it. */
961 prev_p->next = p->next;
963 temp_slots = p->next;
970 /* Find the temp slot corresponding to the object at address X. */
972 static struct temp_slot *
973 find_temp_slot_from_address (rtx x)
978 for (p = temp_slots; p; p = p->next)
983 else if (XEXP (p->slot, 0) == x
985 || (GET_CODE (x) == PLUS
986 && XEXP (x, 0) == virtual_stack_vars_rtx
987 && GET_CODE (XEXP (x, 1)) == CONST_INT
988 && INTVAL (XEXP (x, 1)) >= p->base_offset
989 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
992 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
993 for (next = p->address; next; next = XEXP (next, 1))
994 if (XEXP (next, 0) == x)
998 /* If we have a sum involving a register, see if it points to a temp
1000 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1001 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1003 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1004 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1010 /* Indicate that NEW is an alternate way of referring to the temp slot
1011 that previously was known by OLD. */
1014 update_temp_slot_address (rtx old, rtx new)
1016 struct temp_slot *p;
1018 if (rtx_equal_p (old, new))
1021 p = find_temp_slot_from_address (old);
1023 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1024 is a register, see if one operand of the PLUS is a temporary
1025 location. If so, NEW points into it. Otherwise, if both OLD and
1026 NEW are a PLUS and if there is a register in common between them.
1027 If so, try a recursive call on those values. */
1030 if (GET_CODE (old) != PLUS)
1033 if (GET_CODE (new) == REG)
1035 update_temp_slot_address (XEXP (old, 0), new);
1036 update_temp_slot_address (XEXP (old, 1), new);
1039 else if (GET_CODE (new) != PLUS)
1042 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1043 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1044 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1045 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1046 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1047 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1048 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1049 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1054 /* Otherwise add an alias for the temp's address. */
1055 else if (p->address == 0)
1059 if (GET_CODE (p->address) != EXPR_LIST)
1060 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1062 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1066 /* If X could be a reference to a temporary slot, mark the fact that its
1067 address was taken. */
1070 mark_temp_addr_taken (rtx x)
1072 struct temp_slot *p;
1077 /* If X is not in memory or is at a constant address, it cannot be in
1078 a temporary slot. */
1079 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1082 p = find_temp_slot_from_address (XEXP (x, 0));
1087 /* If X could be a reference to a temporary slot, mark that slot as
1088 belonging to the to one level higher than the current level. If X
1089 matched one of our slots, just mark that one. Otherwise, we can't
1090 easily predict which it is, so upgrade all of them. Kept slots
1091 need not be touched.
1093 This is called when an ({...}) construct occurs and a statement
1094 returns a value in memory. */
1097 preserve_temp_slots (rtx x)
1099 struct temp_slot *p = 0;
1101 /* If there is no result, we still might have some objects whose address
1102 were taken, so we need to make sure they stay around. */
1105 for (p = temp_slots; p; p = p->next)
1106 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1112 /* If X is a register that is being used as a pointer, see if we have
1113 a temporary slot we know it points to. To be consistent with
1114 the code below, we really should preserve all non-kept slots
1115 if we can't find a match, but that seems to be much too costly. */
1116 if (GET_CODE (x) == REG && REG_POINTER (x))
1117 p = find_temp_slot_from_address (x);
1119 /* If X is not in memory or is at a constant address, it cannot be in
1120 a temporary slot, but it can contain something whose address was
1122 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1124 for (p = temp_slots; p; p = p->next)
1125 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1131 /* First see if we can find a match. */
1133 p = find_temp_slot_from_address (XEXP (x, 0));
1137 /* Move everything at our level whose address was taken to our new
1138 level in case we used its address. */
1139 struct temp_slot *q;
1141 if (p->level == temp_slot_level)
1143 for (q = temp_slots; q; q = q->next)
1144 if (q != p && q->addr_taken && q->level == p->level)
1153 /* Otherwise, preserve all non-kept slots at this level. */
1154 for (p = temp_slots; p; p = p->next)
1155 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1159 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1160 with that RTL_EXPR, promote it into a temporary slot at the present
1161 level so it will not be freed when we free slots made in the
1165 preserve_rtl_expr_result (rtx x)
1167 struct temp_slot *p;
1169 /* If X is not in memory or is at a constant address, it cannot be in
1170 a temporary slot. */
1171 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1174 /* If we can find a match, move it to our level unless it is already at
1176 p = find_temp_slot_from_address (XEXP (x, 0));
1179 p->level = MIN (p->level, temp_slot_level);
1186 /* Free all temporaries used so far. This is normally called at the end
1187 of generating code for a statement. Don't free any temporaries
1188 currently in use for an RTL_EXPR that hasn't yet been emitted.
1189 We could eventually do better than this since it can be reused while
1190 generating the same RTL_EXPR, but this is complex and probably not
1194 free_temp_slots (void)
1196 struct temp_slot *p;
1198 for (p = temp_slots; p; p = p->next)
1199 if (p->in_use && p->level == temp_slot_level && ! p->keep
1200 && p->rtl_expr == 0)
1203 combine_temp_slots ();
1206 /* Free all temporary slots used in T, an RTL_EXPR node. */
1209 free_temps_for_rtl_expr (tree t)
1211 struct temp_slot *p;
1213 for (p = temp_slots; p; p = p->next)
1214 if (p->rtl_expr == t)
1216 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1217 needs to be preserved. This can happen if a temporary in
1218 the RTL_EXPR was addressed; preserve_temp_slots will move
1219 the temporary into a higher level. */
1220 if (temp_slot_level <= p->level)
1223 p->rtl_expr = NULL_TREE;
1226 combine_temp_slots ();
1229 /* Mark all temporaries ever allocated in this function as not suitable
1230 for reuse until the current level is exited. */
1233 mark_all_temps_used (void)
1235 struct temp_slot *p;
1237 for (p = temp_slots; p; p = p->next)
1239 p->in_use = p->keep = 1;
1240 p->level = MIN (p->level, temp_slot_level);
1244 /* Push deeper into the nesting level for stack temporaries. */
1247 push_temp_slots (void)
1252 /* Pop a temporary nesting level. All slots in use in the current level
1256 pop_temp_slots (void)
1258 struct temp_slot *p;
1260 for (p = temp_slots; p; p = p->next)
1261 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1264 combine_temp_slots ();
1269 /* Initialize temporary slots. */
1272 init_temp_slots (void)
1274 /* We have not allocated any temporaries yet. */
1276 temp_slot_level = 0;
1277 var_temp_slot_level = 0;
1278 target_temp_slot_level = 0;
1281 /* Retroactively move an auto variable from a register to a stack
1282 slot. This is done when an address-reference to the variable is
1283 seen. If RESCAN is true, all previously emitted instructions are
1284 examined and modified to handle the fact that DECL is now
1288 put_var_into_stack (tree decl, int rescan)
1291 enum machine_mode promoted_mode, decl_mode;
1292 struct function *function = 0;
1294 int can_use_addressof;
1295 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1296 int usedp = (TREE_USED (decl)
1297 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1299 context = decl_function_context (decl);
1301 /* Get the current rtl used for this object and its original mode. */
1302 reg = (TREE_CODE (decl) == SAVE_EXPR
1303 ? SAVE_EXPR_RTL (decl)
1304 : DECL_RTL_IF_SET (decl));
1306 /* No need to do anything if decl has no rtx yet
1307 since in that case caller is setting TREE_ADDRESSABLE
1308 and a stack slot will be assigned when the rtl is made. */
1312 /* Get the declared mode for this object. */
1313 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1314 : DECL_MODE (decl));
1315 /* Get the mode it's actually stored in. */
1316 promoted_mode = GET_MODE (reg);
1318 /* If this variable comes from an outer function, find that
1319 function's saved context. Don't use find_function_data here,
1320 because it might not be in any active function.
1321 FIXME: Is that really supposed to happen?
1322 It does in ObjC at least. */
1323 if (context != current_function_decl && context != inline_function_decl)
1324 for (function = outer_function_chain; function; function = function->outer)
1325 if (function->decl == context)
1328 /* If this is a variable-sized object or a structure passed by invisible
1329 reference, with a pseudo to address it, put that pseudo into the stack
1330 if the var is non-local. */
1331 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1332 && GET_CODE (reg) == MEM
1333 && GET_CODE (XEXP (reg, 0)) == REG
1334 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1336 reg = XEXP (reg, 0);
1337 decl_mode = promoted_mode = GET_MODE (reg);
1340 /* If this variable lives in the current function and we don't need to put it
1341 in the stack for the sake of setjmp or the non-locality, try to keep it in
1342 a register until we know we actually need the address. */
1345 && ! (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl))
1347 /* FIXME make it work for promoted modes too */
1348 && decl_mode == promoted_mode
1349 #ifdef NON_SAVING_SETJMP
1350 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1354 /* If we can't use ADDRESSOF, make sure we see through one we already
1356 if (! can_use_addressof && GET_CODE (reg) == MEM
1357 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1358 reg = XEXP (XEXP (reg, 0), 0);
1360 /* Now we should have a value that resides in one or more pseudo regs. */
1362 if (GET_CODE (reg) == REG)
1364 if (can_use_addressof)
1365 gen_mem_addressof (reg, decl, rescan);
1367 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1368 decl_mode, volatilep, 0, usedp, 0);
1370 else if (GET_CODE (reg) == CONCAT)
1372 /* A CONCAT contains two pseudos; put them both in the stack.
1373 We do it so they end up consecutive.
1374 We fixup references to the parts only after we fixup references
1375 to the whole CONCAT, lest we do double fixups for the latter
1377 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1378 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1379 rtx lopart = XEXP (reg, 0);
1380 rtx hipart = XEXP (reg, 1);
1381 #ifdef FRAME_GROWS_DOWNWARD
1382 /* Since part 0 should have a lower address, do it second. */
1383 put_reg_into_stack (function, hipart, part_type, part_mode,
1384 part_mode, volatilep, 0, 0, 0);
1385 put_reg_into_stack (function, lopart, part_type, part_mode,
1386 part_mode, volatilep, 0, 0, 0);
1388 put_reg_into_stack (function, lopart, part_type, part_mode,
1389 part_mode, volatilep, 0, 0, 0);
1390 put_reg_into_stack (function, hipart, part_type, part_mode,
1391 part_mode, volatilep, 0, 0, 0);
1394 /* Change the CONCAT into a combined MEM for both parts. */
1395 PUT_CODE (reg, MEM);
1396 MEM_ATTRS (reg) = 0;
1398 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1399 already computed alias sets. Here we want to re-generate. */
1401 SET_DECL_RTL (decl, NULL);
1402 set_mem_attributes (reg, decl, 1);
1404 SET_DECL_RTL (decl, reg);
1406 /* The two parts are in memory order already.
1407 Use the lower parts address as ours. */
1408 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1409 /* Prevent sharing of rtl that might lose. */
1410 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1411 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1412 if (usedp && rescan)
1414 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1416 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1417 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1424 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1425 into the stack frame of FUNCTION (0 means the current function).
1426 DECL_MODE is the machine mode of the user-level data type.
1427 PROMOTED_MODE is the machine mode of the register.
1428 VOLATILE_P is nonzero if this is for a "volatile" decl.
1429 USED_P is nonzero if this reg might have already been used in an insn. */
1432 put_reg_into_stack (struct function *function, rtx reg, tree type,
1433 enum machine_mode promoted_mode, enum machine_mode decl_mode,
1434 int volatile_p, unsigned int original_regno, int used_p, htab_t ht)
1436 struct function *func = function ? function : cfun;
1438 unsigned int regno = original_regno;
1441 regno = REGNO (reg);
1443 if (regno < func->x_max_parm_reg)
1444 new = func->x_parm_reg_stack_loc[regno];
1447 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1449 PUT_CODE (reg, MEM);
1450 PUT_MODE (reg, decl_mode);
1451 XEXP (reg, 0) = XEXP (new, 0);
1452 MEM_ATTRS (reg) = 0;
1453 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1454 MEM_VOLATILE_P (reg) = volatile_p;
1456 /* If this is a memory ref that contains aggregate components,
1457 mark it as such for cse and loop optimize. If we are reusing a
1458 previously generated stack slot, then we need to copy the bit in
1459 case it was set for other reasons. For instance, it is set for
1460 __builtin_va_alist. */
1463 MEM_SET_IN_STRUCT_P (reg,
1464 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1465 set_mem_alias_set (reg, get_alias_set (type));
1469 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1472 /* Make sure that all refs to the variable, previously made
1473 when it was a register, are fixed up to be valid again.
1474 See function above for meaning of arguments. */
1477 schedule_fixup_var_refs (struct function *function, rtx reg, tree type,
1478 enum machine_mode promoted_mode, htab_t ht)
1480 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1484 struct var_refs_queue *temp;
1486 temp = ggc_alloc (sizeof (struct var_refs_queue));
1487 temp->modified = reg;
1488 temp->promoted_mode = promoted_mode;
1489 temp->unsignedp = unsigned_p;
1490 temp->next = function->fixup_var_refs_queue;
1491 function->fixup_var_refs_queue = temp;
1494 /* Variable is local; fix it up now. */
1495 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1499 fixup_var_refs (rtx var, enum machine_mode promoted_mode, int unsignedp,
1500 rtx may_share, htab_t ht)
1503 rtx first_insn = get_insns ();
1504 struct sequence_stack *stack = seq_stack;
1505 tree rtl_exps = rtl_expr_chain;
1507 /* If there's a hash table, it must record all uses of VAR. */
1512 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1517 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1518 stack == 0, may_share);
1520 /* Scan all pending sequences too. */
1521 for (; stack; stack = stack->next)
1523 push_to_full_sequence (stack->first, stack->last);
1524 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1525 stack->next != 0, may_share);
1526 /* Update remembered end of sequence
1527 in case we added an insn at the end. */
1528 stack->last = get_last_insn ();
1532 /* Scan all waiting RTL_EXPRs too. */
1533 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1535 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1536 if (seq != const0_rtx && seq != 0)
1538 push_to_sequence (seq);
1539 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1546 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1547 some part of an insn. Return a struct fixup_replacement whose OLD
1548 value is equal to X. Allocate a new structure if no such entry exists. */
1550 static struct fixup_replacement *
1551 find_fixup_replacement (struct fixup_replacement **replacements, rtx x)
1553 struct fixup_replacement *p;
1555 /* See if we have already replaced this. */
1556 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1561 p = xmalloc (sizeof (struct fixup_replacement));
1564 p->next = *replacements;
1571 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1572 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1573 for the current function. MAY_SHARE is either a MEM that is not
1574 to be unshared or a list of them. */
1577 fixup_var_refs_insns (rtx insn, rtx var, enum machine_mode promoted_mode,
1578 int unsignedp, int toplevel, rtx may_share)
1582 /* fixup_var_refs_insn might modify insn, so save its next
1584 rtx next = NEXT_INSN (insn);
1586 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1587 the three sequences they (potentially) contain, and process
1588 them recursively. The CALL_INSN itself is not interesting. */
1590 if (GET_CODE (insn) == CALL_INSN
1591 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1595 /* Look at the Normal call, sibling call and tail recursion
1596 sequences attached to the CALL_PLACEHOLDER. */
1597 for (i = 0; i < 3; i++)
1599 rtx seq = XEXP (PATTERN (insn), i);
1602 push_to_sequence (seq);
1603 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1605 XEXP (PATTERN (insn), i) = get_insns ();
1611 else if (INSN_P (insn))
1612 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1619 /* Look up the insns which reference VAR in HT and fix them up. Other
1620 arguments are the same as fixup_var_refs_insns.
1622 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1623 because the hash table will point straight to the interesting insn
1624 (inside the CALL_PLACEHOLDER). */
1627 fixup_var_refs_insns_with_hash (htab_t ht, rtx var, enum machine_mode promoted_mode,
1628 int unsignedp, rtx may_share)
1630 struct insns_for_mem_entry tmp;
1631 struct insns_for_mem_entry *ime;
1635 ime = htab_find (ht, &tmp);
1636 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1637 if (INSN_P (XEXP (insn_list, 0)))
1638 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1639 unsignedp, 1, may_share);
1643 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1644 the insn under examination, VAR is the variable to fix up
1645 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1646 TOPLEVEL is nonzero if this is the main insn chain for this
1650 fixup_var_refs_insn (rtx insn, rtx var, enum machine_mode promoted_mode,
1651 int unsignedp, int toplevel, rtx no_share)
1654 rtx set, prev, prev_set;
1657 /* Remember the notes in case we delete the insn. */
1658 note = REG_NOTES (insn);
1660 /* If this is a CLOBBER of VAR, delete it.
1662 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1663 and REG_RETVAL notes too. */
1664 if (GET_CODE (PATTERN (insn)) == CLOBBER
1665 && (XEXP (PATTERN (insn), 0) == var
1666 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1667 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1668 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1670 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1671 /* The REG_LIBCALL note will go away since we are going to
1672 turn INSN into a NOTE, so just delete the
1673 corresponding REG_RETVAL note. */
1674 remove_note (XEXP (note, 0),
1675 find_reg_note (XEXP (note, 0), REG_RETVAL,
1681 /* The insn to load VAR from a home in the arglist
1682 is now a no-op. When we see it, just delete it.
1683 Similarly if this is storing VAR from a register from which
1684 it was loaded in the previous insn. This will occur
1685 when an ADDRESSOF was made for an arglist slot. */
1687 && (set = single_set (insn)) != 0
1688 && SET_DEST (set) == var
1689 /* If this represents the result of an insn group,
1690 don't delete the insn. */
1691 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1692 && (rtx_equal_p (SET_SRC (set), var)
1693 || (GET_CODE (SET_SRC (set)) == REG
1694 && (prev = prev_nonnote_insn (insn)) != 0
1695 && (prev_set = single_set (prev)) != 0
1696 && SET_DEST (prev_set) == SET_SRC (set)
1697 && rtx_equal_p (SET_SRC (prev_set), var))))
1703 struct fixup_replacement *replacements = 0;
1704 rtx next_insn = NEXT_INSN (insn);
1706 if (SMALL_REGISTER_CLASSES)
1708 /* If the insn that copies the results of a CALL_INSN
1709 into a pseudo now references VAR, we have to use an
1710 intermediate pseudo since we want the life of the
1711 return value register to be only a single insn.
1713 If we don't use an intermediate pseudo, such things as
1714 address computations to make the address of VAR valid
1715 if it is not can be placed between the CALL_INSN and INSN.
1717 To make sure this doesn't happen, we record the destination
1718 of the CALL_INSN and see if the next insn uses both that
1721 if (call_dest != 0 && GET_CODE (insn) == INSN
1722 && reg_mentioned_p (var, PATTERN (insn))
1723 && reg_mentioned_p (call_dest, PATTERN (insn)))
1725 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1727 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1729 PATTERN (insn) = replace_rtx (PATTERN (insn),
1733 if (GET_CODE (insn) == CALL_INSN
1734 && GET_CODE (PATTERN (insn)) == SET)
1735 call_dest = SET_DEST (PATTERN (insn));
1736 else if (GET_CODE (insn) == CALL_INSN
1737 && GET_CODE (PATTERN (insn)) == PARALLEL
1738 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1739 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1744 /* See if we have to do anything to INSN now that VAR is in
1745 memory. If it needs to be loaded into a pseudo, use a single
1746 pseudo for the entire insn in case there is a MATCH_DUP
1747 between two operands. We pass a pointer to the head of
1748 a list of struct fixup_replacements. If fixup_var_refs_1
1749 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1750 it will record them in this list.
1752 If it allocated a pseudo for any replacement, we copy into
1755 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1756 &replacements, no_share);
1758 /* If this is last_parm_insn, and any instructions were output
1759 after it to fix it up, then we must set last_parm_insn to
1760 the last such instruction emitted. */
1761 if (insn == last_parm_insn)
1762 last_parm_insn = PREV_INSN (next_insn);
1764 while (replacements)
1766 struct fixup_replacement *next;
1768 if (GET_CODE (replacements->new) == REG)
1773 /* OLD might be a (subreg (mem)). */
1774 if (GET_CODE (replacements->old) == SUBREG)
1776 = fixup_memory_subreg (replacements->old, insn,
1780 = fixup_stack_1 (replacements->old, insn);
1782 insert_before = insn;
1784 /* If we are changing the mode, do a conversion.
1785 This might be wasteful, but combine.c will
1786 eliminate much of the waste. */
1788 if (GET_MODE (replacements->new)
1789 != GET_MODE (replacements->old))
1792 convert_move (replacements->new,
1793 replacements->old, unsignedp);
1798 seq = gen_move_insn (replacements->new,
1801 emit_insn_before (seq, insert_before);
1804 next = replacements->next;
1805 free (replacements);
1806 replacements = next;
1810 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1811 But don't touch other insns referred to by reg-notes;
1812 we will get them elsewhere. */
1815 if (GET_CODE (note) != INSN_LIST)
1817 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1819 note = XEXP (note, 1);
1823 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1824 See if the rtx expression at *LOC in INSN needs to be changed.
1826 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1827 contain a list of original rtx's and replacements. If we find that we need
1828 to modify this insn by replacing a memory reference with a pseudo or by
1829 making a new MEM to implement a SUBREG, we consult that list to see if
1830 we have already chosen a replacement. If none has already been allocated,
1831 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1832 or the SUBREG, as appropriate, to the pseudo. */
1835 fixup_var_refs_1 (rtx var, enum machine_mode promoted_mode, rtx *loc, rtx insn,
1836 struct fixup_replacement **replacements, rtx no_share)
1840 RTX_CODE code = GET_CODE (x);
1843 struct fixup_replacement *replacement;
1848 if (XEXP (x, 0) == var)
1850 /* Prevent sharing of rtl that might lose. */
1851 rtx sub = copy_rtx (XEXP (var, 0));
1853 if (! validate_change (insn, loc, sub, 0))
1855 rtx y = gen_reg_rtx (GET_MODE (sub));
1858 /* We should be able to replace with a register or all is lost.
1859 Note that we can't use validate_change to verify this, since
1860 we're not caring for replacing all dups simultaneously. */
1861 if (! validate_replace_rtx (*loc, y, insn))
1864 /* Careful! First try to recognize a direct move of the
1865 value, mimicking how things are done in gen_reload wrt
1866 PLUS. Consider what happens when insn is a conditional
1867 move instruction and addsi3 clobbers flags. */
1870 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1874 if (recog_memoized (new_insn) < 0)
1876 /* That failed. Fall back on force_operand and hope. */
1879 sub = force_operand (sub, y);
1881 emit_insn (gen_move_insn (y, sub));
1887 /* Don't separate setter from user. */
1888 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1889 insn = PREV_INSN (insn);
1892 emit_insn_before (seq, insn);
1900 /* If we already have a replacement, use it. Otherwise,
1901 try to fix up this address in case it is invalid. */
1903 replacement = find_fixup_replacement (replacements, var);
1904 if (replacement->new)
1906 *loc = replacement->new;
1910 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1912 /* Unless we are forcing memory to register or we changed the mode,
1913 we can leave things the way they are if the insn is valid. */
1915 INSN_CODE (insn) = -1;
1916 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1917 && recog_memoized (insn) >= 0)
1920 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1924 /* If X contains VAR, we need to unshare it here so that we update
1925 each occurrence separately. But all identical MEMs in one insn
1926 must be replaced with the same rtx because of the possibility of
1929 if (reg_mentioned_p (var, x))
1931 replacement = find_fixup_replacement (replacements, x);
1932 if (replacement->new == 0)
1933 replacement->new = copy_most_rtx (x, no_share);
1935 *loc = x = replacement->new;
1936 code = GET_CODE (x);
1953 /* Note that in some cases those types of expressions are altered
1954 by optimize_bit_field, and do not survive to get here. */
1955 if (XEXP (x, 0) == var
1956 || (GET_CODE (XEXP (x, 0)) == SUBREG
1957 && SUBREG_REG (XEXP (x, 0)) == var))
1959 /* Get TEM as a valid MEM in the mode presently in the insn.
1961 We don't worry about the possibility of MATCH_DUP here; it
1962 is highly unlikely and would be tricky to handle. */
1965 if (GET_CODE (tem) == SUBREG)
1967 if (GET_MODE_BITSIZE (GET_MODE (tem))
1968 > GET_MODE_BITSIZE (GET_MODE (var)))
1970 replacement = find_fixup_replacement (replacements, var);
1971 if (replacement->new == 0)
1972 replacement->new = gen_reg_rtx (GET_MODE (var));
1973 SUBREG_REG (tem) = replacement->new;
1975 /* The following code works only if we have a MEM, so we
1976 need to handle the subreg here. We directly substitute
1977 it assuming that a subreg must be OK here. We already
1978 scheduled a replacement to copy the mem into the
1984 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
1987 tem = fixup_stack_1 (tem, insn);
1989 /* Unless we want to load from memory, get TEM into the proper mode
1990 for an extract from memory. This can only be done if the
1991 extract is at a constant position and length. */
1993 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1994 && GET_CODE (XEXP (x, 2)) == CONST_INT
1995 && ! mode_dependent_address_p (XEXP (tem, 0))
1996 && ! MEM_VOLATILE_P (tem))
1998 enum machine_mode wanted_mode = VOIDmode;
1999 enum machine_mode is_mode = GET_MODE (tem);
2000 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2002 if (GET_CODE (x) == ZERO_EXTRACT)
2004 enum machine_mode new_mode
2005 = mode_for_extraction (EP_extzv, 1);
2006 if (new_mode != MAX_MACHINE_MODE)
2007 wanted_mode = new_mode;
2009 else if (GET_CODE (x) == SIGN_EXTRACT)
2011 enum machine_mode new_mode
2012 = mode_for_extraction (EP_extv, 1);
2013 if (new_mode != MAX_MACHINE_MODE)
2014 wanted_mode = new_mode;
2017 /* If we have a narrower mode, we can do something. */
2018 if (wanted_mode != VOIDmode
2019 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2021 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2022 rtx old_pos = XEXP (x, 2);
2025 /* If the bytes and bits are counted differently, we
2026 must adjust the offset. */
2027 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2028 offset = (GET_MODE_SIZE (is_mode)
2029 - GET_MODE_SIZE (wanted_mode) - offset);
2031 pos %= GET_MODE_BITSIZE (wanted_mode);
2033 newmem = adjust_address_nv (tem, wanted_mode, offset);
2035 /* Make the change and see if the insn remains valid. */
2036 INSN_CODE (insn) = -1;
2037 XEXP (x, 0) = newmem;
2038 XEXP (x, 2) = GEN_INT (pos);
2040 if (recog_memoized (insn) >= 0)
2043 /* Otherwise, restore old position. XEXP (x, 0) will be
2045 XEXP (x, 2) = old_pos;
2049 /* If we get here, the bitfield extract insn can't accept a memory
2050 reference. Copy the input into a register. */
2052 tem1 = gen_reg_rtx (GET_MODE (tem));
2053 emit_insn_before (gen_move_insn (tem1, tem), insn);
2060 if (SUBREG_REG (x) == var)
2062 /* If this is a special SUBREG made because VAR was promoted
2063 from a wider mode, replace it with VAR and call ourself
2064 recursively, this time saying that the object previously
2065 had its current mode (by virtue of the SUBREG). */
2067 if (SUBREG_PROMOTED_VAR_P (x))
2070 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2075 /* If this SUBREG makes VAR wider, it has become a paradoxical
2076 SUBREG with VAR in memory, but these aren't allowed at this
2077 stage of the compilation. So load VAR into a pseudo and take
2078 a SUBREG of that pseudo. */
2079 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2081 replacement = find_fixup_replacement (replacements, var);
2082 if (replacement->new == 0)
2083 replacement->new = gen_reg_rtx (promoted_mode);
2084 SUBREG_REG (x) = replacement->new;
2088 /* See if we have already found a replacement for this SUBREG.
2089 If so, use it. Otherwise, make a MEM and see if the insn
2090 is recognized. If not, or if we should force MEM into a register,
2091 make a pseudo for this SUBREG. */
2092 replacement = find_fixup_replacement (replacements, x);
2093 if (replacement->new)
2095 enum machine_mode mode = GET_MODE (x);
2096 *loc = replacement->new;
2098 /* Careful! We may have just replaced a SUBREG by a MEM, which
2099 means that the insn may have become invalid again. We can't
2100 in this case make a new replacement since we already have one
2101 and we must deal with MATCH_DUPs. */
2102 if (GET_CODE (replacement->new) == MEM)
2104 INSN_CODE (insn) = -1;
2105 if (recog_memoized (insn) >= 0)
2108 fixup_var_refs_1 (replacement->new, mode, &PATTERN (insn),
2109 insn, replacements, no_share);
2115 replacement->new = *loc = fixup_memory_subreg (x, insn,
2118 INSN_CODE (insn) = -1;
2119 if (! flag_force_mem && recog_memoized (insn) >= 0)
2122 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2128 /* First do special simplification of bit-field references. */
2129 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2130 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2131 optimize_bit_field (x, insn, 0);
2132 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2133 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2134 optimize_bit_field (x, insn, 0);
2136 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2137 into a register and then store it back out. */
2138 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2139 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2140 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2141 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2142 > GET_MODE_SIZE (GET_MODE (var))))
2144 replacement = find_fixup_replacement (replacements, var);
2145 if (replacement->new == 0)
2146 replacement->new = gen_reg_rtx (GET_MODE (var));
2148 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2149 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2152 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2153 insn into a pseudo and store the low part of the pseudo into VAR. */
2154 if (GET_CODE (SET_DEST (x)) == SUBREG
2155 && SUBREG_REG (SET_DEST (x)) == var
2156 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2157 > GET_MODE_SIZE (GET_MODE (var))))
2159 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2160 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2167 rtx dest = SET_DEST (x);
2168 rtx src = SET_SRC (x);
2169 rtx outerdest = dest;
2171 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2172 || GET_CODE (dest) == SIGN_EXTRACT
2173 || GET_CODE (dest) == ZERO_EXTRACT)
2174 dest = XEXP (dest, 0);
2176 if (GET_CODE (src) == SUBREG)
2177 src = SUBREG_REG (src);
2179 /* If VAR does not appear at the top level of the SET
2180 just scan the lower levels of the tree. */
2182 if (src != var && dest != var)
2185 /* We will need to rerecognize this insn. */
2186 INSN_CODE (insn) = -1;
2188 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2189 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2191 /* Since this case will return, ensure we fixup all the
2193 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2194 insn, replacements, no_share);
2195 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2196 insn, replacements, no_share);
2197 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2198 insn, replacements, no_share);
2200 tem = XEXP (outerdest, 0);
2202 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2203 that may appear inside a ZERO_EXTRACT.
2204 This was legitimate when the MEM was a REG. */
2205 if (GET_CODE (tem) == SUBREG
2206 && SUBREG_REG (tem) == var)
2207 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2209 tem = fixup_stack_1 (tem, insn);
2211 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2212 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2213 && ! mode_dependent_address_p (XEXP (tem, 0))
2214 && ! MEM_VOLATILE_P (tem))
2216 enum machine_mode wanted_mode;
2217 enum machine_mode is_mode = GET_MODE (tem);
2218 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2220 wanted_mode = mode_for_extraction (EP_insv, 0);
2222 /* If we have a narrower mode, we can do something. */
2223 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2225 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2226 rtx old_pos = XEXP (outerdest, 2);
2229 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2230 offset = (GET_MODE_SIZE (is_mode)
2231 - GET_MODE_SIZE (wanted_mode) - offset);
2233 pos %= GET_MODE_BITSIZE (wanted_mode);
2235 newmem = adjust_address_nv (tem, wanted_mode, offset);
2237 /* Make the change and see if the insn remains valid. */
2238 INSN_CODE (insn) = -1;
2239 XEXP (outerdest, 0) = newmem;
2240 XEXP (outerdest, 2) = GEN_INT (pos);
2242 if (recog_memoized (insn) >= 0)
2245 /* Otherwise, restore old position. XEXP (x, 0) will be
2247 XEXP (outerdest, 2) = old_pos;
2251 /* If we get here, the bit-field store doesn't allow memory
2252 or isn't located at a constant position. Load the value into
2253 a register, do the store, and put it back into memory. */
2255 tem1 = gen_reg_rtx (GET_MODE (tem));
2256 emit_insn_before (gen_move_insn (tem1, tem), insn);
2257 emit_insn_after (gen_move_insn (tem, tem1), insn);
2258 XEXP (outerdest, 0) = tem1;
2262 /* STRICT_LOW_PART is a no-op on memory references
2263 and it can cause combinations to be unrecognizable,
2266 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2267 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2269 /* A valid insn to copy VAR into or out of a register
2270 must be left alone, to avoid an infinite loop here.
2271 If the reference to VAR is by a subreg, fix that up,
2272 since SUBREG is not valid for a memref.
2273 Also fix up the address of the stack slot.
2275 Note that we must not try to recognize the insn until
2276 after we know that we have valid addresses and no
2277 (subreg (mem ...) ...) constructs, since these interfere
2278 with determining the validity of the insn. */
2280 if ((SET_SRC (x) == var
2281 || (GET_CODE (SET_SRC (x)) == SUBREG
2282 && SUBREG_REG (SET_SRC (x)) == var))
2283 && (GET_CODE (SET_DEST (x)) == REG
2284 || (GET_CODE (SET_DEST (x)) == SUBREG
2285 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2286 && GET_MODE (var) == promoted_mode
2287 && x == single_set (insn))
2291 if (GET_CODE (SET_SRC (x)) == SUBREG
2292 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2293 > GET_MODE_SIZE (GET_MODE (var))))
2295 /* This (subreg VAR) is now a paradoxical subreg. We need
2296 to replace VAR instead of the subreg. */
2297 replacement = find_fixup_replacement (replacements, var);
2298 if (replacement->new == NULL_RTX)
2299 replacement->new = gen_reg_rtx (GET_MODE (var));
2300 SUBREG_REG (SET_SRC (x)) = replacement->new;
2304 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2305 if (replacement->new)
2306 SET_SRC (x) = replacement->new;
2307 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2308 SET_SRC (x) = replacement->new
2309 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2312 SET_SRC (x) = replacement->new
2313 = fixup_stack_1 (SET_SRC (x), insn);
2316 if (recog_memoized (insn) >= 0)
2319 /* INSN is not valid, but we know that we want to
2320 copy SET_SRC (x) to SET_DEST (x) in some way. So
2321 we generate the move and see whether it requires more
2322 than one insn. If it does, we emit those insns and
2323 delete INSN. Otherwise, we can just replace the pattern
2324 of INSN; we have already verified above that INSN has
2325 no other function that to do X. */
2327 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2328 if (NEXT_INSN (pat) != NULL_RTX)
2330 last = emit_insn_before (pat, insn);
2332 /* INSN might have REG_RETVAL or other important notes, so
2333 we need to store the pattern of the last insn in the
2334 sequence into INSN similarly to the normal case. LAST
2335 should not have REG_NOTES, but we allow them if INSN has
2337 if (REG_NOTES (last) && REG_NOTES (insn))
2339 if (REG_NOTES (last))
2340 REG_NOTES (insn) = REG_NOTES (last);
2341 PATTERN (insn) = PATTERN (last);
2346 PATTERN (insn) = PATTERN (pat);
2351 if ((SET_DEST (x) == var
2352 || (GET_CODE (SET_DEST (x)) == SUBREG
2353 && SUBREG_REG (SET_DEST (x)) == var))
2354 && (GET_CODE (SET_SRC (x)) == REG
2355 || (GET_CODE (SET_SRC (x)) == SUBREG
2356 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2357 && GET_MODE (var) == promoted_mode
2358 && x == single_set (insn))
2362 if (GET_CODE (SET_DEST (x)) == SUBREG)
2363 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2366 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2368 if (recog_memoized (insn) >= 0)
2371 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2372 if (NEXT_INSN (pat) != NULL_RTX)
2374 last = emit_insn_before (pat, insn);
2376 /* INSN might have REG_RETVAL or other important notes, so
2377 we need to store the pattern of the last insn in the
2378 sequence into INSN similarly to the normal case. LAST
2379 should not have REG_NOTES, but we allow them if INSN has
2381 if (REG_NOTES (last) && REG_NOTES (insn))
2383 if (REG_NOTES (last))
2384 REG_NOTES (insn) = REG_NOTES (last);
2385 PATTERN (insn) = PATTERN (last);
2390 PATTERN (insn) = PATTERN (pat);
2395 /* Otherwise, storing into VAR must be handled specially
2396 by storing into a temporary and copying that into VAR
2397 with a new insn after this one. Note that this case
2398 will be used when storing into a promoted scalar since
2399 the insn will now have different modes on the input
2400 and output and hence will be invalid (except for the case
2401 of setting it to a constant, which does not need any
2402 change if it is valid). We generate extra code in that case,
2403 but combine.c will eliminate it. */
2408 rtx fixeddest = SET_DEST (x);
2409 enum machine_mode temp_mode;
2411 /* STRICT_LOW_PART can be discarded, around a MEM. */
2412 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2413 fixeddest = XEXP (fixeddest, 0);
2414 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2415 if (GET_CODE (fixeddest) == SUBREG)
2417 fixeddest = fixup_memory_subreg (fixeddest, insn,
2419 temp_mode = GET_MODE (fixeddest);
2423 fixeddest = fixup_stack_1 (fixeddest, insn);
2424 temp_mode = promoted_mode;
2427 temp = gen_reg_rtx (temp_mode);
2429 emit_insn_after (gen_move_insn (fixeddest,
2430 gen_lowpart (GET_MODE (fixeddest),
2434 SET_DEST (x) = temp;
2442 /* Nothing special about this RTX; fix its operands. */
2444 fmt = GET_RTX_FORMAT (code);
2445 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2448 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2450 else if (fmt[i] == 'E')
2453 for (j = 0; j < XVECLEN (x, i); j++)
2454 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2455 insn, replacements, no_share);
2460 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2461 The REG was placed on the stack, so X now has the form (SUBREG:m1
2464 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2465 must be emitted to compute NEWADDR, put them before INSN.
2467 UNCRITICAL nonzero means accept paradoxical subregs.
2468 This is used for subregs found inside REG_NOTES. */
2471 fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode, int uncritical)
2474 rtx mem = SUBREG_REG (x);
2475 rtx addr = XEXP (mem, 0);
2476 enum machine_mode mode = GET_MODE (x);
2479 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2480 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2483 offset = SUBREG_BYTE (x);
2484 if (BYTES_BIG_ENDIAN)
2485 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2486 the offset so that it points to the right location within the
2488 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2490 if (!flag_force_addr
2491 && memory_address_p (mode, plus_constant (addr, offset)))
2492 /* Shortcut if no insns need be emitted. */
2493 return adjust_address (mem, mode, offset);
2496 result = adjust_address (mem, mode, offset);
2500 emit_insn_before (seq, insn);
2504 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2505 Replace subexpressions of X in place.
2506 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2507 Otherwise return X, with its contents possibly altered.
2509 INSN, PROMOTED_MODE and UNCRITICAL are as for
2510 fixup_memory_subreg. */
2513 walk_fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode,
2523 code = GET_CODE (x);
2525 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2526 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2528 /* Nothing special about this RTX; fix its operands. */
2530 fmt = GET_RTX_FORMAT (code);
2531 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2534 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2535 promoted_mode, uncritical);
2536 else if (fmt[i] == 'E')
2539 for (j = 0; j < XVECLEN (x, i); j++)
2541 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2542 promoted_mode, uncritical);
2548 /* For each memory ref within X, if it refers to a stack slot
2549 with an out of range displacement, put the address in a temp register
2550 (emitting new insns before INSN to load these registers)
2551 and alter the memory ref to use that register.
2552 Replace each such MEM rtx with a copy, to avoid clobberage. */
2555 fixup_stack_1 (rtx x, rtx insn)
2558 RTX_CODE code = GET_CODE (x);
2563 rtx ad = XEXP (x, 0);
2564 /* If we have address of a stack slot but it's not valid
2565 (displacement is too large), compute the sum in a register. */
2566 if (GET_CODE (ad) == PLUS
2567 && GET_CODE (XEXP (ad, 0)) == REG
2568 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2569 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2570 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2571 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2572 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2574 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2575 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2576 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2577 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2580 if (memory_address_p (GET_MODE (x), ad))
2584 temp = copy_to_reg (ad);
2587 emit_insn_before (seq, insn);
2588 return replace_equiv_address (x, temp);
2593 fmt = GET_RTX_FORMAT (code);
2594 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2597 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2598 else if (fmt[i] == 'E')
2601 for (j = 0; j < XVECLEN (x, i); j++)
2602 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2608 /* Optimization: a bit-field instruction whose field
2609 happens to be a byte or halfword in memory
2610 can be changed to a move instruction.
2612 We call here when INSN is an insn to examine or store into a bit-field.
2613 BODY is the SET-rtx to be altered.
2615 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2616 (Currently this is called only from function.c, and EQUIV_MEM
2620 optimize_bit_field (rtx body, rtx insn, rtx *equiv_mem)
2625 enum machine_mode mode;
2627 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2628 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2629 bitfield = SET_DEST (body), destflag = 1;
2631 bitfield = SET_SRC (body), destflag = 0;
2633 /* First check that the field being stored has constant size and position
2634 and is in fact a byte or halfword suitably aligned. */
2636 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2637 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2638 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2640 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2644 /* Now check that the containing word is memory, not a register,
2645 and that it is safe to change the machine mode. */
2647 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2648 memref = XEXP (bitfield, 0);
2649 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2651 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2652 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2653 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2654 memref = SUBREG_REG (XEXP (bitfield, 0));
2655 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2657 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2658 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2661 && ! mode_dependent_address_p (XEXP (memref, 0))
2662 && ! MEM_VOLATILE_P (memref))
2664 /* Now adjust the address, first for any subreg'ing
2665 that we are now getting rid of,
2666 and then for which byte of the word is wanted. */
2668 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2671 /* Adjust OFFSET to count bits from low-address byte. */
2672 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2673 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2674 - offset - INTVAL (XEXP (bitfield, 1)));
2676 /* Adjust OFFSET to count bytes from low-address byte. */
2677 offset /= BITS_PER_UNIT;
2678 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2680 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2681 / UNITS_PER_WORD) * UNITS_PER_WORD;
2682 if (BYTES_BIG_ENDIAN)
2683 offset -= (MIN (UNITS_PER_WORD,
2684 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2685 - MIN (UNITS_PER_WORD,
2686 GET_MODE_SIZE (GET_MODE (memref))));
2690 memref = adjust_address (memref, mode, offset);
2691 insns = get_insns ();
2693 emit_insn_before (insns, insn);
2695 /* Store this memory reference where
2696 we found the bit field reference. */
2700 validate_change (insn, &SET_DEST (body), memref, 1);
2701 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2703 rtx src = SET_SRC (body);
2704 while (GET_CODE (src) == SUBREG
2705 && SUBREG_BYTE (src) == 0)
2706 src = SUBREG_REG (src);
2707 if (GET_MODE (src) != GET_MODE (memref))
2708 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2709 validate_change (insn, &SET_SRC (body), src, 1);
2711 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2712 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2713 /* This shouldn't happen because anything that didn't have
2714 one of these modes should have got converted explicitly
2715 and then referenced through a subreg.
2716 This is so because the original bit-field was
2717 handled by agg_mode and so its tree structure had
2718 the same mode that memref now has. */
2723 rtx dest = SET_DEST (body);
2725 while (GET_CODE (dest) == SUBREG
2726 && SUBREG_BYTE (dest) == 0
2727 && (GET_MODE_CLASS (GET_MODE (dest))
2728 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2729 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2731 dest = SUBREG_REG (dest);
2733 validate_change (insn, &SET_DEST (body), dest, 1);
2735 if (GET_MODE (dest) == GET_MODE (memref))
2736 validate_change (insn, &SET_SRC (body), memref, 1);
2739 /* Convert the mem ref to the destination mode. */
2740 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2743 convert_move (newreg, memref,
2744 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2748 validate_change (insn, &SET_SRC (body), newreg, 1);
2752 /* See if we can convert this extraction or insertion into
2753 a simple move insn. We might not be able to do so if this
2754 was, for example, part of a PARALLEL.
2756 If we succeed, write out any needed conversions. If we fail,
2757 it is hard to guess why we failed, so don't do anything
2758 special; just let the optimization be suppressed. */
2760 if (apply_change_group () && seq)
2761 emit_insn_before (seq, insn);
2766 /* These routines are responsible for converting virtual register references
2767 to the actual hard register references once RTL generation is complete.
2769 The following four variables are used for communication between the
2770 routines. They contain the offsets of the virtual registers from their
2771 respective hard registers. */
2773 static int in_arg_offset;
2774 static int var_offset;
2775 static int dynamic_offset;
2776 static int out_arg_offset;
2777 static int cfa_offset;
2779 /* In most machines, the stack pointer register is equivalent to the bottom
2782 #ifndef STACK_POINTER_OFFSET
2783 #define STACK_POINTER_OFFSET 0
2786 /* If not defined, pick an appropriate default for the offset of dynamically
2787 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2788 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2790 #ifndef STACK_DYNAMIC_OFFSET
2792 /* The bottom of the stack points to the actual arguments. If
2793 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2794 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2795 stack space for register parameters is not pushed by the caller, but
2796 rather part of the fixed stack areas and hence not included in
2797 `current_function_outgoing_args_size'. Nevertheless, we must allow
2798 for it when allocating stack dynamic objects. */
2800 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2801 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2802 ((ACCUMULATE_OUTGOING_ARGS \
2803 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2804 + (STACK_POINTER_OFFSET)) \
2807 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2808 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2809 + (STACK_POINTER_OFFSET))
2813 /* On most machines, the CFA coincides with the first incoming parm. */
2815 #ifndef ARG_POINTER_CFA_OFFSET
2816 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2819 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2820 had its address taken. DECL is the decl or SAVE_EXPR for the
2821 object stored in the register, for later use if we do need to force
2822 REG into the stack. REG is overwritten by the MEM like in
2823 put_reg_into_stack. RESCAN is true if previously emitted
2824 instructions must be rescanned and modified now that the REG has
2825 been transformed. */
2828 gen_mem_addressof (rtx reg, tree decl, int rescan)
2830 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2833 /* Calculate this before we start messing with decl's RTL. */
2834 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2836 /* If the original REG was a user-variable, then so is the REG whose
2837 address is being taken. Likewise for unchanging. */
2838 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2839 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2841 PUT_CODE (reg, MEM);
2842 MEM_ATTRS (reg) = 0;
2847 tree type = TREE_TYPE (decl);
2848 enum machine_mode decl_mode
2849 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2850 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2851 : DECL_RTL_IF_SET (decl));
2853 PUT_MODE (reg, decl_mode);
2855 /* Clear DECL_RTL momentarily so functions below will work
2856 properly, then set it again. */
2857 if (DECL_P (decl) && decl_rtl == reg)
2858 SET_DECL_RTL (decl, 0);
2860 set_mem_attributes (reg, decl, 1);
2861 set_mem_alias_set (reg, set);
2863 if (DECL_P (decl) && decl_rtl == reg)
2864 SET_DECL_RTL (decl, reg);
2867 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0)))
2868 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2872 /* This can only happen during reload. Clear the same flag bits as
2874 MEM_VOLATILE_P (reg) = 0;
2875 RTX_UNCHANGING_P (reg) = 0;
2876 MEM_IN_STRUCT_P (reg) = 0;
2877 MEM_SCALAR_P (reg) = 0;
2878 MEM_ATTRS (reg) = 0;
2880 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2886 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2889 flush_addressof (tree decl)
2891 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2892 && DECL_RTL (decl) != 0
2893 && GET_CODE (DECL_RTL (decl)) == MEM
2894 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2895 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2896 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2899 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2902 put_addressof_into_stack (rtx r, htab_t ht)
2905 int volatile_p, used_p;
2907 rtx reg = XEXP (r, 0);
2909 if (GET_CODE (reg) != REG)
2912 decl = ADDRESSOF_DECL (r);
2915 type = TREE_TYPE (decl);
2916 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2917 && TREE_THIS_VOLATILE (decl));
2918 used_p = (TREE_USED (decl)
2919 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2928 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2929 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2932 /* List of replacements made below in purge_addressof_1 when creating
2933 bitfield insertions. */
2934 static rtx purge_bitfield_addressof_replacements;
2936 /* List of replacements made below in purge_addressof_1 for patterns
2937 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2938 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2939 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2940 enough in complex cases, e.g. when some field values can be
2941 extracted by usage MEM with narrower mode. */
2942 static rtx purge_addressof_replacements;
2944 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2945 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2946 the stack. If the function returns FALSE then the replacement could not
2947 be made. If MAY_POSTPONE is true and we would not put the addressof
2948 to stack, postpone processing of the insn. */
2951 purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
2959 bool libcall = false;
2961 /* Re-start here to avoid recursion in common cases. */
2968 /* Is this a libcall? */
2970 libcall = REG_NOTE_KIND (*loc) == REG_RETVAL;
2972 code = GET_CODE (x);
2974 /* If we don't return in any of the cases below, we will recurse inside
2975 the RTX, which will normally result in any ADDRESSOF being forced into
2979 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1,
2981 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0,
2985 else if (code == ADDRESSOF)
2989 if (GET_CODE (XEXP (x, 0)) != MEM)
2990 put_addressof_into_stack (x, ht);
2992 /* We must create a copy of the rtx because it was created by
2993 overwriting a REG rtx which is always shared. */
2994 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2995 if (validate_change (insn, loc, sub, 0)
2996 || validate_replace_rtx (x, sub, insn))
3001 /* If SUB is a hard or virtual register, try it as a pseudo-register.
3002 Otherwise, perhaps SUB is an expression, so generate code to compute
3004 if (GET_CODE (sub) == REG && REGNO (sub) <= LAST_VIRTUAL_REGISTER)
3005 sub = copy_to_reg (sub);
3007 sub = force_operand (sub, NULL_RTX);
3009 if (! validate_change (insn, loc, sub, 0)
3010 && ! validate_replace_rtx (x, sub, insn))
3013 insns = get_insns ();
3015 emit_insn_before (insns, insn);
3019 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3021 rtx sub = XEXP (XEXP (x, 0), 0);
3023 if (GET_CODE (sub) == MEM)
3024 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3025 else if (GET_CODE (sub) == REG
3026 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3028 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3030 int size_x, size_sub;
3034 /* Postpone for now, so that we do not emit bitfield arithmetics
3035 unless there is some benefit from it. */
3036 if (!postponed_insns || XEXP (postponed_insns, 0) != insn)
3037 postponed_insns = alloc_INSN_LIST (insn, postponed_insns);
3043 /* When processing REG_NOTES look at the list of
3044 replacements done on the insn to find the register that X
3048 for (tem = purge_bitfield_addressof_replacements;
3050 tem = XEXP (XEXP (tem, 1), 1))
3051 if (rtx_equal_p (x, XEXP (tem, 0)))
3053 *loc = XEXP (XEXP (tem, 1), 0);
3057 /* See comment for purge_addressof_replacements. */
3058 for (tem = purge_addressof_replacements;
3060 tem = XEXP (XEXP (tem, 1), 1))
3061 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3063 rtx z = XEXP (XEXP (tem, 1), 0);
3065 if (GET_MODE (x) == GET_MODE (z)
3066 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3067 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3070 /* It can happen that the note may speak of things
3071 in a wider (or just different) mode than the
3072 code did. This is especially true of
3075 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3078 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3079 && (GET_MODE_SIZE (GET_MODE (x))
3080 > GET_MODE_SIZE (GET_MODE (z))))
3082 /* This can occur as a result in invalid
3083 pointer casts, e.g. float f; ...
3084 *(long long int *)&f.
3085 ??? We could emit a warning here, but
3086 without a line number that wouldn't be
3088 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3091 z = gen_lowpart (GET_MODE (x), z);
3097 /* When we are processing the REG_NOTES of the last instruction
3098 of a libcall, there will be typically no replacements
3099 for that insn; the replacements happened before, piecemeal
3100 fashion. OTOH we are not interested in the details of
3101 this for the REG_EQUAL note, we want to know the big picture,
3102 which can be succinctly described with a simple SUBREG.
3103 Note that removing the REG_EQUAL note is not an option
3104 on the last insn of a libcall, so we must do a replacement. */
3106 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
3108 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
3109 [0 S8 A32]), which can be expressed with a simple
3111 if ((GET_MODE_SIZE (GET_MODE (x))
3112 <= GET_MODE_SIZE (GET_MODE (sub)))
3113 /* Again, invalid pointer casts (as in
3114 compile/990203-1.c) can require paradoxical
3116 || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3117 && (GET_MODE_SIZE (GET_MODE (x))
3118 > GET_MODE_SIZE (GET_MODE (sub)))
3121 *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
3124 /* ??? Are there other cases we should handle? */
3126 /* Sometimes we may not be able to find the replacement. For
3127 example when the original insn was a MEM in a wider mode,
3128 and the note is part of a sign extension of a narrowed
3129 version of that MEM. Gcc testcase compile/990829-1.c can
3130 generate an example of this situation. Rather than complain
3131 we return false, which will prompt our caller to remove the
3136 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3137 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3139 /* Do not frob unchanging MEMs. If a later reference forces the
3140 pseudo to the stack, we can wind up with multiple writes to
3141 an unchanging memory, which is invalid. */
3142 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3145 /* Don't even consider working with paradoxical subregs,
3146 or the moral equivalent seen here. */
3147 else if (size_x <= size_sub
3148 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3150 /* Do a bitfield insertion to mirror what would happen
3157 rtx p = PREV_INSN (insn);
3160 val = gen_reg_rtx (GET_MODE (x));
3161 if (! validate_change (insn, loc, val, 0))
3163 /* Discard the current sequence and put the
3164 ADDRESSOF on stack. */
3170 emit_insn_before (seq, insn);
3171 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3175 store_bit_field (sub, size_x, 0, GET_MODE (x),
3176 val, GET_MODE_SIZE (GET_MODE (sub)));
3178 /* Make sure to unshare any shared rtl that store_bit_field
3179 might have created. */
3180 unshare_all_rtl_again (get_insns ());
3184 p = emit_insn_after (seq, insn);
3185 if (NEXT_INSN (insn))
3186 compute_insns_for_mem (NEXT_INSN (insn),
3187 p ? NEXT_INSN (p) : NULL_RTX,
3192 rtx p = PREV_INSN (insn);
3195 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3196 GET_MODE (x), GET_MODE (x),
3197 GET_MODE_SIZE (GET_MODE (sub)));
3199 if (! validate_change (insn, loc, val, 0))
3201 /* Discard the current sequence and put the
3202 ADDRESSOF on stack. */
3209 emit_insn_before (seq, insn);
3210 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3214 /* Remember the replacement so that the same one can be done
3215 on the REG_NOTES. */
3216 purge_bitfield_addressof_replacements
3217 = gen_rtx_EXPR_LIST (VOIDmode, x,
3220 purge_bitfield_addressof_replacements));
3222 /* We replaced with a reg -- all done. */
3227 else if (validate_change (insn, loc, sub, 0))
3229 /* Remember the replacement so that the same one can be done
3230 on the REG_NOTES. */
3231 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3235 for (tem = purge_addressof_replacements;
3237 tem = XEXP (XEXP (tem, 1), 1))
3238 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3240 XEXP (XEXP (tem, 1), 0) = sub;
3243 purge_addressof_replacements
3244 = gen_rtx_EXPR_LIST (VOIDmode, XEXP (x, 0),
3245 gen_rtx_EXPR_LIST (VOIDmode, sub,
3246 purge_addressof_replacements));
3254 /* Scan all subexpressions. */
3255 fmt = GET_RTX_FORMAT (code);
3256 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3259 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0,
3261 else if (*fmt == 'E')
3262 for (j = 0; j < XVECLEN (x, i); j++)
3263 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0,
3270 /* Return a hash value for K, a REG. */
3273 insns_for_mem_hash (const void *k)
3275 /* Use the address of the key for the hash value. */
3276 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3277 return htab_hash_pointer (m->key);
3280 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3283 insns_for_mem_comp (const void *k1, const void *k2)
3285 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3286 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3287 return m1->key == m2->key;
3290 struct insns_for_mem_walk_info
3292 /* The hash table that we are using to record which INSNs use which
3296 /* The INSN we are currently processing. */
3299 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3300 to find the insns that use the REGs in the ADDRESSOFs. */
3304 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3305 that might be used in an ADDRESSOF expression, record this INSN in
3306 the hash table given by DATA (which is really a pointer to an
3307 insns_for_mem_walk_info structure). */
3310 insns_for_mem_walk (rtx *r, void *data)
3312 struct insns_for_mem_walk_info *ifmwi
3313 = (struct insns_for_mem_walk_info *) data;
3314 struct insns_for_mem_entry tmp;
3315 tmp.insns = NULL_RTX;
3317 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3318 && GET_CODE (XEXP (*r, 0)) == REG)
3321 tmp.key = XEXP (*r, 0);
3322 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3325 *e = ggc_alloc (sizeof (tmp));
3326 memcpy (*e, &tmp, sizeof (tmp));
3329 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3331 struct insns_for_mem_entry *ifme;
3333 ifme = htab_find (ifmwi->ht, &tmp);
3335 /* If we have not already recorded this INSN, do so now. Since
3336 we process the INSNs in order, we know that if we have
3337 recorded it it must be at the front of the list. */
3338 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3339 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3346 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3347 which REGs in HT. */
3350 compute_insns_for_mem (rtx insns, rtx last_insn, htab_t ht)
3353 struct insns_for_mem_walk_info ifmwi;
3356 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3357 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3361 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3365 /* Helper function for purge_addressof called through for_each_rtx.
3366 Returns true iff the rtl is an ADDRESSOF. */
3369 is_addressof (rtx *rtl, void *data ATTRIBUTE_UNUSED)
3371 return GET_CODE (*rtl) == ADDRESSOF;
3374 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3375 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3379 purge_addressof (rtx insns)
3384 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3385 requires a fixup pass over the instruction stream to correct
3386 INSNs that depended on the REG being a REG, and not a MEM. But,
3387 these fixup passes are slow. Furthermore, most MEMs are not
3388 mentioned in very many instructions. So, we speed up the process
3389 by pre-calculating which REGs occur in which INSNs; that allows
3390 us to perform the fixup passes much more quickly. */
3391 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3392 compute_insns_for_mem (insns, NULL_RTX, ht);
3394 postponed_insns = NULL;
3396 for (insn = insns; insn; insn = NEXT_INSN (insn))
3399 if (! purge_addressof_1 (&PATTERN (insn), insn,
3400 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht))
3401 /* If we could not replace the ADDRESSOFs in the insn,
3402 something is wrong. */
3405 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht))
3407 /* If we could not replace the ADDRESSOFs in the insn's notes,
3408 we can just remove the offending notes instead. */
3411 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3413 /* If we find a REG_RETVAL note then the insn is a libcall.
3414 Such insns must have REG_EQUAL notes as well, in order
3415 for later passes of the compiler to work. So it is not
3416 safe to delete the notes here, and instead we abort. */
3417 if (REG_NOTE_KIND (note) == REG_RETVAL)
3419 if (for_each_rtx (¬e, is_addressof, NULL))
3420 remove_note (insn, note);
3425 /* Process the postponed insns. */
3426 while (postponed_insns)
3428 insn = XEXP (postponed_insns, 0);
3429 tmp = postponed_insns;
3430 postponed_insns = XEXP (postponed_insns, 1);
3431 free_INSN_LIST_node (tmp);
3433 if (! purge_addressof_1 (&PATTERN (insn), insn,
3434 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht))
3439 purge_bitfield_addressof_replacements = 0;
3440 purge_addressof_replacements = 0;
3442 /* REGs are shared. purge_addressof will destructively replace a REG
3443 with a MEM, which creates shared MEMs.
3445 Unfortunately, the children of put_reg_into_stack assume that MEMs
3446 referring to the same stack slot are shared (fixup_var_refs and
3447 the associated hash table code).
3449 So, we have to do another unsharing pass after we have flushed any
3450 REGs that had their address taken into the stack.
3452 It may be worth tracking whether or not we converted any REGs into
3453 MEMs to avoid this overhead when it is not needed. */
3454 unshare_all_rtl_again (get_insns ());
3457 /* Convert a SET of a hard subreg to a set of the appropriate hard
3458 register. A subroutine of purge_hard_subreg_sets. */
3461 purge_single_hard_subreg_set (rtx pattern)
3463 rtx reg = SET_DEST (pattern);
3464 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3467 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3468 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3470 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3471 GET_MODE (SUBREG_REG (reg)),
3474 reg = SUBREG_REG (reg);
3478 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3480 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3481 SET_DEST (pattern) = reg;
3485 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3486 only such SETs that we expect to see are those left in because
3487 integrate can't handle sets of parts of a return value register.
3489 We don't use alter_subreg because we only want to eliminate subregs
3490 of hard registers. */
3493 purge_hard_subreg_sets (rtx insn)
3495 for (; insn; insn = NEXT_INSN (insn))
3499 rtx pattern = PATTERN (insn);
3500 switch (GET_CODE (pattern))
3503 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3504 purge_single_hard_subreg_set (pattern);
3509 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3511 rtx inner_pattern = XVECEXP (pattern, 0, j);
3512 if (GET_CODE (inner_pattern) == SET
3513 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3514 purge_single_hard_subreg_set (inner_pattern);
3525 /* Pass through the INSNS of function FNDECL and convert virtual register
3526 references to hard register references. */
3529 instantiate_virtual_regs (tree fndecl, rtx insns)
3534 /* Compute the offsets to use for this function. */
3535 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3536 var_offset = STARTING_FRAME_OFFSET;
3537 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3538 out_arg_offset = STACK_POINTER_OFFSET;
3539 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3541 /* Scan all variables and parameters of this function. For each that is
3542 in memory, instantiate all virtual registers if the result is a valid
3543 address. If not, we do it later. That will handle most uses of virtual
3544 regs on many machines. */
3545 instantiate_decls (fndecl, 1);
3547 /* Initialize recognition, indicating that volatile is OK. */
3550 /* Scan through all the insns, instantiating every virtual register still
3552 for (insn = insns; insn; insn = NEXT_INSN (insn))
3553 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3554 || GET_CODE (insn) == CALL_INSN)
3556 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3557 if (INSN_DELETED_P (insn))
3559 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3560 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3561 if (GET_CODE (insn) == CALL_INSN)
3562 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3565 /* Past this point all ASM statements should match. Verify that
3566 to avoid failures later in the compilation process. */
3567 if (asm_noperands (PATTERN (insn)) >= 0
3568 && ! check_asm_operands (PATTERN (insn)))
3569 instantiate_virtual_regs_lossage (insn);
3572 /* Instantiate the stack slots for the parm registers, for later use in
3573 addressof elimination. */
3574 for (i = 0; i < max_parm_reg; ++i)
3575 if (parm_reg_stack_loc[i])
3576 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3578 /* Now instantiate the remaining register equivalences for debugging info.
3579 These will not be valid addresses. */
3580 instantiate_decls (fndecl, 0);
3582 /* Indicate that, from now on, assign_stack_local should use
3583 frame_pointer_rtx. */
3584 virtuals_instantiated = 1;
3587 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3588 all virtual registers in their DECL_RTL's.
3590 If VALID_ONLY, do this only if the resulting address is still valid.
3591 Otherwise, always do it. */
3594 instantiate_decls (tree fndecl, int valid_only)
3598 /* Process all parameters of the function. */
3599 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3601 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3602 HOST_WIDE_INT size_rtl;
3604 instantiate_decl (DECL_RTL (decl), size, valid_only);
3606 /* If the parameter was promoted, then the incoming RTL mode may be
3607 larger than the declared type size. We must use the larger of
3609 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3610 size = MAX (size_rtl, size);
3611 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3614 /* Now process all variables defined in the function or its subblocks. */
3615 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3618 /* Subroutine of instantiate_decls: Process all decls in the given
3619 BLOCK node and all its subblocks. */
3622 instantiate_decls_1 (tree let, int valid_only)
3626 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3627 if (DECL_RTL_SET_P (t))
3628 instantiate_decl (DECL_RTL (t),
3629 int_size_in_bytes (TREE_TYPE (t)),
3632 /* Process all subblocks. */
3633 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3634 instantiate_decls_1 (t, valid_only);
3637 /* Subroutine of the preceding procedures: Given RTL representing a
3638 decl and the size of the object, do any instantiation required.
3640 If VALID_ONLY is nonzero, it means that the RTL should only be
3641 changed if the new address is valid. */
3644 instantiate_decl (rtx x, HOST_WIDE_INT size, int valid_only)
3646 enum machine_mode mode;
3649 /* If this is not a MEM, no need to do anything. Similarly if the
3650 address is a constant or a register that is not a virtual register. */
3652 if (x == 0 || GET_CODE (x) != MEM)
3656 if (CONSTANT_P (addr)
3657 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3658 || (GET_CODE (addr) == REG
3659 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3660 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3663 /* If we should only do this if the address is valid, copy the address.
3664 We need to do this so we can undo any changes that might make the
3665 address invalid. This copy is unfortunate, but probably can't be
3669 addr = copy_rtx (addr);
3671 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3673 if (valid_only && size >= 0)
3675 unsigned HOST_WIDE_INT decl_size = size;
3677 /* Now verify that the resulting address is valid for every integer or
3678 floating-point mode up to and including SIZE bytes long. We do this
3679 since the object might be accessed in any mode and frame addresses
3682 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3683 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3684 mode = GET_MODE_WIDER_MODE (mode))
3685 if (! memory_address_p (mode, addr))
3688 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3689 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3690 mode = GET_MODE_WIDER_MODE (mode))
3691 if (! memory_address_p (mode, addr))
3695 /* Put back the address now that we have updated it and we either know
3696 it is valid or we don't care whether it is valid. */
3701 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3702 is a virtual register, return the equivalent hard register and set the
3703 offset indirectly through the pointer. Otherwise, return 0. */
3706 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
3709 HOST_WIDE_INT offset;
3711 if (x == virtual_incoming_args_rtx)
3712 new = arg_pointer_rtx, offset = in_arg_offset;
3713 else if (x == virtual_stack_vars_rtx)
3714 new = frame_pointer_rtx, offset = var_offset;
3715 else if (x == virtual_stack_dynamic_rtx)
3716 new = stack_pointer_rtx, offset = dynamic_offset;
3717 else if (x == virtual_outgoing_args_rtx)
3718 new = stack_pointer_rtx, offset = out_arg_offset;
3719 else if (x == virtual_cfa_rtx)
3720 new = arg_pointer_rtx, offset = cfa_offset;
3729 /* Called when instantiate_virtual_regs has failed to update the instruction.
3730 Usually this means that non-matching instruction has been emit, however for
3731 asm statements it may be the problem in the constraints. */
3733 instantiate_virtual_regs_lossage (rtx insn)
3735 if (asm_noperands (PATTERN (insn)) >= 0)
3737 error_for_asm (insn, "impossible constraint in `asm'");
3743 /* Given a pointer to a piece of rtx and an optional pointer to the
3744 containing object, instantiate any virtual registers present in it.
3746 If EXTRA_INSNS, we always do the replacement and generate
3747 any extra insns before OBJECT. If it zero, we do nothing if replacement
3750 Return 1 if we either had nothing to do or if we were able to do the
3751 needed replacement. Return 0 otherwise; we only return zero if
3752 EXTRA_INSNS is zero.
3754 We first try some simple transformations to avoid the creation of extra
3758 instantiate_virtual_regs_1 (rtx *loc, rtx object, int extra_insns)
3763 HOST_WIDE_INT offset = 0;
3769 /* Re-start here to avoid recursion in common cases. */
3776 /* We may have detected and deleted invalid asm statements. */
3777 if (object && INSN_P (object) && INSN_DELETED_P (object))
3780 code = GET_CODE (x);
3782 /* Check for some special cases. */
3800 /* We are allowed to set the virtual registers. This means that
3801 the actual register should receive the source minus the
3802 appropriate offset. This is used, for example, in the handling
3803 of non-local gotos. */
3804 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3806 rtx src = SET_SRC (x);
3808 /* We are setting the register, not using it, so the relevant
3809 offset is the negative of the offset to use were we using
3812 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3814 /* The only valid sources here are PLUS or REG. Just do
3815 the simplest possible thing to handle them. */
3816 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3818 instantiate_virtual_regs_lossage (object);
3823 if (GET_CODE (src) != REG)
3824 temp = force_operand (src, NULL_RTX);
3827 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3831 emit_insn_before (seq, object);
3834 if (! validate_change (object, &SET_SRC (x), temp, 0)
3836 instantiate_virtual_regs_lossage (object);
3841 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3846 /* Handle special case of virtual register plus constant. */
3847 if (CONSTANT_P (XEXP (x, 1)))
3849 rtx old, new_offset;
3851 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3852 if (GET_CODE (XEXP (x, 0)) == PLUS)
3854 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3856 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3858 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3867 #ifdef POINTERS_EXTEND_UNSIGNED
3868 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3869 we can commute the PLUS and SUBREG because pointers into the
3870 frame are well-behaved. */
3871 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3872 && GET_CODE (XEXP (x, 1)) == CONST_INT
3874 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3876 && validate_change (object, loc,
3877 plus_constant (gen_lowpart (ptr_mode,
3880 + INTVAL (XEXP (x, 1))),
3884 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3886 /* We know the second operand is a constant. Unless the
3887 first operand is a REG (which has been already checked),
3888 it needs to be checked. */
3889 if (GET_CODE (XEXP (x, 0)) != REG)
3897 new_offset = plus_constant (XEXP (x, 1), offset);
3899 /* If the new constant is zero, try to replace the sum with just
3901 if (new_offset == const0_rtx
3902 && validate_change (object, loc, new, 0))
3905 /* Next try to replace the register and new offset.
3906 There are two changes to validate here and we can't assume that
3907 in the case of old offset equals new just changing the register
3908 will yield a valid insn. In the interests of a little efficiency,
3909 however, we only call validate change once (we don't queue up the
3910 changes and then call apply_change_group). */
3914 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3915 : (XEXP (x, 0) = new,
3916 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3924 /* Otherwise copy the new constant into a register and replace
3925 constant with that register. */
3926 temp = gen_reg_rtx (Pmode);
3928 if (validate_change (object, &XEXP (x, 1), temp, 0))
3929 emit_insn_before (gen_move_insn (temp, new_offset), object);
3932 /* If that didn't work, replace this expression with a
3933 register containing the sum. */
3936 new = gen_rtx_PLUS (Pmode, new, new_offset);
3939 temp = force_operand (new, NULL_RTX);
3943 emit_insn_before (seq, object);
3944 if (! validate_change (object, loc, temp, 0)
3945 && ! validate_replace_rtx (x, temp, object))
3947 instantiate_virtual_regs_lossage (object);
3956 /* Fall through to generic two-operand expression case. */
3962 case DIV: case UDIV:
3963 case MOD: case UMOD:
3964 case AND: case IOR: case XOR:
3965 case ROTATERT: case ROTATE:
3966 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3968 case GE: case GT: case GEU: case GTU:
3969 case LE: case LT: case LEU: case LTU:
3970 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3971 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3976 /* Most cases of MEM that convert to valid addresses have already been
3977 handled by our scan of decls. The only special handling we
3978 need here is to make a copy of the rtx to ensure it isn't being
3979 shared if we have to change it to a pseudo.
3981 If the rtx is a simple reference to an address via a virtual register,
3982 it can potentially be shared. In such cases, first try to make it
3983 a valid address, which can also be shared. Otherwise, copy it and
3986 First check for common cases that need no processing. These are
3987 usually due to instantiation already being done on a previous instance
3991 if (CONSTANT_ADDRESS_P (temp)
3992 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3993 || temp == arg_pointer_rtx
3995 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3996 || temp == hard_frame_pointer_rtx
3998 || temp == frame_pointer_rtx)
4001 if (GET_CODE (temp) == PLUS
4002 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4003 && (XEXP (temp, 0) == frame_pointer_rtx
4004 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4005 || XEXP (temp, 0) == hard_frame_pointer_rtx
4007 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4008 || XEXP (temp, 0) == arg_pointer_rtx
4013 if (temp == virtual_stack_vars_rtx
4014 || temp == virtual_incoming_args_rtx
4015 || (GET_CODE (temp) == PLUS
4016 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4017 && (XEXP (temp, 0) == virtual_stack_vars_rtx
4018 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
4020 /* This MEM may be shared. If the substitution can be done without
4021 the need to generate new pseudos, we want to do it in place
4022 so all copies of the shared rtx benefit. The call below will
4023 only make substitutions if the resulting address is still
4026 Note that we cannot pass X as the object in the recursive call
4027 since the insn being processed may not allow all valid
4028 addresses. However, if we were not passed on object, we can
4029 only modify X without copying it if X will have a valid
4032 ??? Also note that this can still lose if OBJECT is an insn that
4033 has less restrictions on an address that some other insn.
4034 In that case, we will modify the shared address. This case
4035 doesn't seem very likely, though. One case where this could
4036 happen is in the case of a USE or CLOBBER reference, but we
4037 take care of that below. */
4039 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4040 object ? object : x, 0))
4043 /* Otherwise make a copy and process that copy. We copy the entire
4044 RTL expression since it might be a PLUS which could also be
4046 *loc = x = copy_rtx (x);
4049 /* Fall through to generic unary operation case. */
4052 case STRICT_LOW_PART:
4054 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4055 case SIGN_EXTEND: case ZERO_EXTEND:
4056 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4057 case FLOAT: case FIX:
4058 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4063 case POPCOUNT: case PARITY:
4064 /* These case either have just one operand or we know that we need not
4065 check the rest of the operands. */
4071 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4072 go ahead and make the invalid one, but do it to a copy. For a REG,
4073 just make the recursive call, since there's no chance of a problem. */
4075 if ((GET_CODE (XEXP (x, 0)) == MEM
4076 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4078 || (GET_CODE (XEXP (x, 0)) == REG
4079 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4082 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4087 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4088 in front of this insn and substitute the temporary. */
4089 if ((new = instantiate_new_reg (x, &offset)) != 0)
4091 temp = plus_constant (new, offset);
4092 if (!validate_change (object, loc, temp, 0))
4098 temp = force_operand (temp, NULL_RTX);
4102 emit_insn_before (seq, object);
4103 if (! validate_change (object, loc, temp, 0)
4104 && ! validate_replace_rtx (x, temp, object))
4105 instantiate_virtual_regs_lossage (object);
4112 if (GET_CODE (XEXP (x, 0)) == REG)
4115 else if (GET_CODE (XEXP (x, 0)) == MEM)
4117 /* If we have a (addressof (mem ..)), do any instantiation inside
4118 since we know we'll be making the inside valid when we finally
4119 remove the ADDRESSOF. */
4120 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4129 /* Scan all subexpressions. */
4130 fmt = GET_RTX_FORMAT (code);
4131 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4134 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4137 else if (*fmt == 'E')
4138 for (j = 0; j < XVECLEN (x, i); j++)
4139 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4146 /* Optimization: assuming this function does not receive nonlocal gotos,
4147 delete the handlers for such, as well as the insns to establish
4148 and disestablish them. */
4151 delete_handlers (void)
4154 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4156 /* Delete the handler by turning off the flag that would
4157 prevent jump_optimize from deleting it.
4158 Also permit deletion of the nonlocal labels themselves
4159 if nothing local refers to them. */
4160 if (GET_CODE (insn) == CODE_LABEL)
4164 LABEL_PRESERVE_P (insn) = 0;
4166 /* Remove it from the nonlocal_label list, to avoid confusing
4168 for (t = nonlocal_labels, last_t = 0; t;
4169 last_t = t, t = TREE_CHAIN (t))
4170 if (DECL_RTL (TREE_VALUE (t)) == insn)
4175 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4177 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4180 if (GET_CODE (insn) == INSN)
4184 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4185 if (reg_mentioned_p (t, PATTERN (insn)))
4191 || (nonlocal_goto_stack_level != 0
4192 && reg_mentioned_p (nonlocal_goto_stack_level,
4194 delete_related_insns (insn);
4199 /* Return the first insn following those generated by `assign_parms'. */
4202 get_first_nonparm_insn (void)
4205 return NEXT_INSN (last_parm_insn);
4206 return get_insns ();
4209 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4210 This means a type for which function calls must pass an address to the
4211 function or get an address back from the function.
4212 EXP may be a type node or an expression (whose type is tested). */
4215 aggregate_value_p (tree exp, tree fntype)
4217 int i, regno, nregs;
4220 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4223 switch (TREE_CODE (fntype))
4226 fntype = get_callee_fndecl (fntype);
4227 fntype = fntype ? TREE_TYPE (fntype) : 0;
4230 fntype = TREE_TYPE (fntype);
4235 case IDENTIFIER_NODE:
4239 /* We don't expect other rtl types here. */
4243 if (TREE_CODE (type) == VOID_TYPE)
4245 if (targetm.calls.return_in_memory (type, fntype))
4247 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4248 and thus can't be returned in registers. */
4249 if (TREE_ADDRESSABLE (type))
4251 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4253 /* Make sure we have suitable call-clobbered regs to return
4254 the value in; if not, we must return it in memory. */
4255 reg = hard_function_value (type, 0, 0);
4257 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4259 if (GET_CODE (reg) != REG)
4262 regno = REGNO (reg);
4263 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
4264 for (i = 0; i < nregs; i++)
4265 if (! call_used_regs[regno + i])
4270 /* Assign RTL expressions to the function's parameters.
4271 This may involve copying them into registers and using
4272 those registers as the RTL for them. */
4275 assign_parms (tree fndecl)
4278 CUMULATIVE_ARGS args_so_far;
4279 /* Total space needed so far for args on the stack,
4280 given as a constant and a tree-expression. */
4281 struct args_size stack_args_size;
4282 tree fntype = TREE_TYPE (fndecl);
4283 tree fnargs = DECL_ARGUMENTS (fndecl), orig_fnargs;
4284 /* This is used for the arg pointer when referring to stack args. */
4285 rtx internal_arg_pointer;
4286 /* This is a dummy PARM_DECL that we used for the function result if
4287 the function returns a structure. */
4288 tree function_result_decl = 0;
4289 int varargs_setup = 0;
4290 int reg_parm_stack_space ATTRIBUTE_UNUSED = 0;
4291 rtx conversion_insns = 0;
4293 /* Nonzero if function takes extra anonymous args.
4294 This means the last named arg must be on the stack
4295 right before the anonymous ones. */
4297 = (TYPE_ARG_TYPES (fntype) != 0
4298 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4299 != void_type_node));
4301 current_function_stdarg = stdarg;
4303 /* If the reg that the virtual arg pointer will be translated into is
4304 not a fixed reg or is the stack pointer, make a copy of the virtual
4305 arg pointer, and address parms via the copy. The frame pointer is
4306 considered fixed even though it is not marked as such.
4308 The second time through, simply use ap to avoid generating rtx. */
4310 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4311 || ! (fixed_regs[ARG_POINTER_REGNUM]
4312 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4313 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4315 internal_arg_pointer = virtual_incoming_args_rtx;
4316 current_function_internal_arg_pointer = internal_arg_pointer;
4318 stack_args_size.constant = 0;
4319 stack_args_size.var = 0;
4321 /* If struct value address is treated as the first argument, make it so. */
4322 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
4323 && ! current_function_returns_pcc_struct
4324 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
4326 tree type = build_pointer_type (TREE_TYPE (fntype));
4328 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4330 DECL_ARG_TYPE (function_result_decl) = type;
4331 TREE_CHAIN (function_result_decl) = fnargs;
4332 fnargs = function_result_decl;
4335 orig_fnargs = fnargs;
4337 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4338 parm_reg_stack_loc = ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4340 if (SPLIT_COMPLEX_ARGS)
4341 fnargs = split_complex_args (fnargs);
4343 #ifdef REG_PARM_STACK_SPACE
4344 #ifdef MAYBE_REG_PARM_STACK_SPACE
4345 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4347 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4351 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4352 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4354 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl, -1);
4357 /* We haven't yet found an argument that we must push and pretend the
4359 current_function_pretend_args_size = 0;
4361 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4365 enum machine_mode promoted_mode, passed_mode;
4366 enum machine_mode nominal_mode, promoted_nominal_mode;
4368 struct locate_and_pad_arg_data locate;
4369 int passed_pointer = 0;
4370 int did_conversion = 0;
4371 tree passed_type = DECL_ARG_TYPE (parm);
4372 tree nominal_type = TREE_TYPE (parm);
4373 int last_named = 0, named_arg;
4376 int pretend_bytes = 0;
4377 int loaded_in_reg = 0;
4379 /* Set LAST_NAMED if this is last named arg before last
4385 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4386 if (DECL_NAME (tem))
4392 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4393 most machines, if this is a varargs/stdarg function, then we treat
4394 the last named arg as if it were anonymous too. */
4395 named_arg = (targetm.calls.strict_argument_naming (&args_so_far)
4398 if (TREE_TYPE (parm) == error_mark_node
4399 /* This can happen after weird syntax errors
4400 or if an enum type is defined among the parms. */
4401 || TREE_CODE (parm) != PARM_DECL
4402 || passed_type == NULL)
4404 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4405 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4406 TREE_USED (parm) = 1;
4410 /* Find mode of arg as it is passed, and mode of arg
4411 as it should be during execution of this function. */
4412 passed_mode = TYPE_MODE (passed_type);
4413 nominal_mode = TYPE_MODE (nominal_type);
4415 /* If the parm's mode is VOID, its value doesn't matter,
4416 and avoid the usual things like emit_move_insn that could crash. */
4417 if (nominal_mode == VOIDmode)
4419 SET_DECL_RTL (parm, const0_rtx);
4420 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4424 /* If the parm is to be passed as a transparent union, use the
4425 type of the first field for the tests below. We have already
4426 verified that the modes are the same. */
4427 if (DECL_TRANSPARENT_UNION (parm)
4428 || (TREE_CODE (passed_type) == UNION_TYPE
4429 && TYPE_TRANSPARENT_UNION (passed_type)))
4430 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4432 /* See if this arg was passed by invisible reference. It is if
4433 it is an object whose size depends on the contents of the
4434 object itself or if the machine requires these objects be passed
4437 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type))
4438 || TREE_ADDRESSABLE (passed_type)
4439 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4440 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4441 passed_type, named_arg)
4445 passed_type = nominal_type = build_pointer_type (passed_type);
4447 passed_mode = nominal_mode = Pmode;
4449 /* See if the frontend wants to pass this by invisible reference. */
4450 else if (passed_type != nominal_type
4451 && POINTER_TYPE_P (passed_type)
4452 && TREE_TYPE (passed_type) == nominal_type)
4454 nominal_type = passed_type;
4456 passed_mode = nominal_mode = Pmode;
4459 promoted_mode = passed_mode;
4461 if (targetm.calls.promote_function_args (TREE_TYPE (fndecl)))
4463 /* Compute the mode in which the arg is actually extended to. */
4464 unsignedp = TREE_UNSIGNED (passed_type);
4465 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4468 /* Let machine desc say which reg (if any) the parm arrives in.
4469 0 means it arrives on the stack. */
4470 #ifdef FUNCTION_INCOMING_ARG
4471 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4472 passed_type, named_arg);
4474 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4475 passed_type, named_arg);
4478 if (entry_parm == 0)
4479 promoted_mode = passed_mode;
4481 /* If this is the last named parameter, do any required setup for
4482 varargs or stdargs. We need to know about the case of this being an
4483 addressable type, in which case we skip the registers it
4484 would have arrived in.
4486 For stdargs, LAST_NAMED will be set for two parameters, the one that
4487 is actually the last named, and the dummy parameter. We only
4488 want to do this action once.
4490 Also, indicate when RTL generation is to be suppressed. */
4491 if (last_named && !varargs_setup)
4493 int varargs_pretend_bytes = 0;
4494 targetm.calls.setup_incoming_varargs (&args_so_far, promoted_mode,
4496 &varargs_pretend_bytes, 0);
4499 /* If the back-end has requested extra stack space, record how
4500 much is needed. Do not change pretend_args_size otherwise
4501 since it may be nonzero from an earlier partial argument. */
4502 if (varargs_pretend_bytes > 0)
4503 current_function_pretend_args_size = varargs_pretend_bytes;
4506 /* Determine parm's home in the stack,
4507 in case it arrives in the stack or we should pretend it did.
4509 Compute the stack position and rtx where the argument arrives
4512 There is one complexity here: If this was a parameter that would
4513 have been passed in registers, but wasn't only because it is
4514 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4515 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4516 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4517 0 as it was the previous time. */
4518 in_regs = entry_parm != 0;
4519 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4522 if (!in_regs && !named_arg)
4525 targetm.calls.pretend_outgoing_varargs_named (&args_so_far);
4528 #ifdef FUNCTION_INCOMING_ARG
4529 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4531 pretend_named) != 0;
4533 in_regs = FUNCTION_ARG (args_so_far, promoted_mode,
4535 pretend_named) != 0;
4540 /* If this parameter was passed both in registers and in the stack,
4541 use the copy on the stack. */
4542 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4545 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4548 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4549 passed_type, named_arg);
4551 #ifndef MAYBE_REG_PARM_STACK_SPACE
4552 /* The caller might already have allocated stack space
4553 for the register parameters. */
4554 && reg_parm_stack_space == 0
4558 /* Part of this argument is passed in registers and part
4559 is passed on the stack. Ask the prologue code to extend
4560 the stack part so that we can recreate the full value.
4562 PRETEND_BYTES is the size of the registers we need to store.
4563 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
4564 stack space that the prologue should allocate.
4566 Internally, gcc assumes that the argument pointer is
4567 aligned to STACK_BOUNDARY bits. This is used both for
4568 alignment optimizations (see init_emit) and to locate
4569 arguments that are aligned to more than PARM_BOUNDARY
4570 bits. We must preserve this invariant by rounding
4571 CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to a stack
4573 pretend_bytes = partial * UNITS_PER_WORD;
4574 current_function_pretend_args_size
4575 = CEIL_ROUND (pretend_bytes, STACK_BYTES);
4577 /* If PRETEND_BYTES != CURRENT_FUNCTION_PRETEND_ARGS_SIZE,
4578 insert the padding before the start of the first pretend
4580 stack_args_size.constant
4581 = (current_function_pretend_args_size - pretend_bytes);
4586 memset (&locate, 0, sizeof (locate));
4587 locate_and_pad_parm (promoted_mode, passed_type, in_regs,
4588 entry_parm ? partial : 0, fndecl,
4589 &stack_args_size, &locate);
4594 /* If we're passing this arg using a reg, make its stack home
4595 the aligned stack slot. */
4597 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset);
4599 offset_rtx = ARGS_SIZE_RTX (locate.offset);
4601 if (offset_rtx == const0_rtx)
4602 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4604 stack_parm = gen_rtx_MEM (promoted_mode,
4605 gen_rtx_PLUS (Pmode,
4606 internal_arg_pointer,
4609 set_mem_attributes (stack_parm, parm, 1);
4610 if (entry_parm && MEM_ATTRS (stack_parm)->align < PARM_BOUNDARY)
4611 set_mem_align (stack_parm, PARM_BOUNDARY);
4613 /* Set also REG_ATTRS if parameter was passed in a register. */
4615 set_reg_attrs_for_parm (entry_parm, stack_parm);
4618 /* If this parm was passed part in regs and part in memory,
4619 pretend it arrived entirely in memory
4620 by pushing the register-part onto the stack.
4622 In the special case of a DImode or DFmode that is split,
4623 we could put it together in a pseudoreg directly,
4624 but for now that's not worth bothering with. */
4628 /* Handle calls that pass values in multiple non-contiguous
4629 locations. The Irix 6 ABI has examples of this. */
4630 if (GET_CODE (entry_parm) == PARALLEL)
4631 emit_group_store (validize_mem (stack_parm), entry_parm,
4633 int_size_in_bytes (TREE_TYPE (parm)));
4636 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
4639 entry_parm = stack_parm;
4642 /* If we didn't decide this parm came in a register,
4643 by default it came on the stack. */
4644 if (entry_parm == 0)
4645 entry_parm = stack_parm;
4647 /* Record permanently how this parm was passed. */
4648 set_decl_incoming_rtl (parm, entry_parm);
4650 /* If there is actually space on the stack for this parm,
4651 count it in stack_args_size; otherwise set stack_parm to 0
4652 to indicate there is no preallocated stack slot for the parm. */
4654 if (entry_parm == stack_parm
4655 || (GET_CODE (entry_parm) == PARALLEL
4656 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4657 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4658 /* On some machines, even if a parm value arrives in a register
4659 there is still an (uninitialized) stack slot allocated for it.
4661 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4662 whether this parameter already has a stack slot allocated,
4663 because an arg block exists only if current_function_args_size
4664 is larger than some threshold, and we haven't calculated that
4665 yet. So, for now, we just assume that stack slots never exist
4667 || REG_PARM_STACK_SPACE (fndecl) > 0
4671 stack_args_size.constant += pretend_bytes + locate.size.constant;
4672 if (locate.size.var)
4673 ADD_PARM_SIZE (stack_args_size, locate.size.var);
4676 /* No stack slot was pushed for this parm. */
4679 /* Update info on where next arg arrives in registers. */
4681 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4682 passed_type, named_arg);
4684 /* If we can't trust the parm stack slot to be aligned enough
4685 for its ultimate type, don't use that slot after entry.
4686 We'll make another stack slot, if we need one. */
4688 unsigned int thisparm_boundary
4689 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4691 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4695 /* If parm was passed in memory, and we need to convert it on entry,
4696 don't store it back in that same slot. */
4697 if (entry_parm == stack_parm
4698 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4701 /* When an argument is passed in multiple locations, we can't
4702 make use of this information, but we can save some copying if
4703 the whole argument is passed in a single register. */
4704 if (GET_CODE (entry_parm) == PARALLEL
4705 && nominal_mode != BLKmode && passed_mode != BLKmode)
4707 int i, len = XVECLEN (entry_parm, 0);
4709 for (i = 0; i < len; i++)
4710 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4711 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4712 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4714 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4716 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4717 set_decl_incoming_rtl (parm, entry_parm);
4722 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4723 in the mode in which it arrives.
4724 STACK_PARM is an RTX for a stack slot where the parameter can live
4725 during the function (in case we want to put it there).
4726 STACK_PARM is 0 if no stack slot was pushed for it.
4728 Now output code if necessary to convert ENTRY_PARM to
4729 the type in which this function declares it,
4730 and store that result in an appropriate place,
4731 which may be a pseudo reg, may be STACK_PARM,
4732 or may be a local stack slot if STACK_PARM is 0.
4734 Set DECL_RTL to that place. */
4736 if (GET_CODE (entry_parm) == PARALLEL && nominal_mode != BLKmode
4737 && XVECLEN (entry_parm, 0) > 1)
4739 /* Reconstitute objects the size of a register or larger using
4740 register operations instead of the stack. */
4741 rtx parmreg = gen_reg_rtx (nominal_mode);
4743 if (REG_P (parmreg))
4745 unsigned int regno = REGNO (parmreg);
4747 emit_group_store (parmreg, entry_parm, TREE_TYPE (parm),
4748 int_size_in_bytes (TREE_TYPE (parm)));
4749 SET_DECL_RTL (parm, parmreg);
4752 if (regno >= max_parm_reg)
4755 int old_max_parm_reg = max_parm_reg;
4757 /* It's slow to expand this one register at a time,
4758 but it's also rare and we need max_parm_reg to be
4759 precisely correct. */
4760 max_parm_reg = regno + 1;
4761 new = ggc_realloc (parm_reg_stack_loc,
4762 max_parm_reg * sizeof (rtx));
4763 memset (new + old_max_parm_reg, 0,
4764 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4765 parm_reg_stack_loc = new;
4766 parm_reg_stack_loc[regno] = stack_parm;
4771 if (nominal_mode == BLKmode
4772 #ifdef BLOCK_REG_PADDING
4773 || (locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward)
4774 && GET_MODE_SIZE (promoted_mode) < UNITS_PER_WORD)
4776 || GET_CODE (entry_parm) == PARALLEL)
4778 /* If a BLKmode arrives in registers, copy it to a stack slot.
4779 Handle calls that pass values in multiple non-contiguous
4780 locations. The Irix 6 ABI has examples of this. */
4781 if (GET_CODE (entry_parm) == REG
4782 || (GET_CODE (entry_parm) == PARALLEL
4783 && (!loaded_in_reg || !optimize)))
4785 int size = int_size_in_bytes (TREE_TYPE (parm));
4786 int size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
4789 /* Note that we will be storing an integral number of words.
4790 So we have to be careful to ensure that we allocate an
4791 integral number of words. We do this below in the
4792 assign_stack_local if space was not allocated in the argument
4793 list. If it was, this will not work if PARM_BOUNDARY is not
4794 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4795 if it becomes a problem. Exception is when BLKmode arrives
4796 with arguments not conforming to word_mode. */
4798 if (stack_parm == 0)
4800 stack_parm = assign_stack_local (BLKmode, size_stored, 0);
4801 PUT_MODE (stack_parm, GET_MODE (entry_parm));
4802 set_mem_attributes (stack_parm, parm, 1);
4804 else if (GET_CODE (entry_parm) == PARALLEL
4805 && GET_MODE(entry_parm) == BLKmode)
4807 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4810 mem = validize_mem (stack_parm);
4812 /* Handle calls that pass values in multiple non-contiguous
4813 locations. The Irix 6 ABI has examples of this. */
4814 if (GET_CODE (entry_parm) == PARALLEL)
4815 emit_group_store (mem, entry_parm, TREE_TYPE (parm), size);
4820 /* If SIZE is that of a mode no bigger than a word, just use
4821 that mode's store operation. */
4822 else if (size <= UNITS_PER_WORD)
4824 enum machine_mode mode
4825 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
4828 #ifdef BLOCK_REG_PADDING
4829 && (size == UNITS_PER_WORD
4830 || (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4831 != (BYTES_BIG_ENDIAN ? upward : downward)))
4835 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
4836 emit_move_insn (change_address (mem, mode, 0), reg);
4839 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
4840 machine must be aligned to the left before storing
4841 to memory. Note that the previous test doesn't
4842 handle all cases (e.g. SIZE == 3). */
4843 else if (size != UNITS_PER_WORD
4844 #ifdef BLOCK_REG_PADDING
4845 && (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4853 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4854 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
4856 x = expand_binop (word_mode, ashl_optab, reg,
4857 GEN_INT (by), 0, 1, OPTAB_WIDEN);
4858 tem = change_address (mem, word_mode, 0);
4859 emit_move_insn (tem, x);
4862 move_block_from_reg (REGNO (entry_parm), mem,
4863 size_stored / UNITS_PER_WORD);
4866 move_block_from_reg (REGNO (entry_parm), mem,
4867 size_stored / UNITS_PER_WORD);
4869 /* If parm is already bound to register pair, don't change
4871 if (! DECL_RTL_SET_P (parm))
4872 SET_DECL_RTL (parm, stack_parm);
4874 else if (! ((! optimize
4875 && ! DECL_REGISTER (parm))
4876 || TREE_SIDE_EFFECTS (parm)
4877 /* If -ffloat-store specified, don't put explicit
4878 float variables into registers. */
4879 || (flag_float_store
4880 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4881 /* Always assign pseudo to structure return or item passed
4882 by invisible reference. */
4883 || passed_pointer || parm == function_result_decl)
4885 /* Store the parm in a pseudoregister during the function, but we
4886 may need to do it in a wider mode. */
4889 unsigned int regno, regnoi = 0, regnor = 0;
4891 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4893 promoted_nominal_mode
4894 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4896 parmreg = gen_reg_rtx (promoted_nominal_mode);
4897 mark_user_reg (parmreg);
4899 /* If this was an item that we received a pointer to, set DECL_RTL
4903 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4905 set_mem_attributes (x, parm, 1);
4906 SET_DECL_RTL (parm, x);
4910 SET_DECL_RTL (parm, parmreg);
4911 maybe_set_unchanging (DECL_RTL (parm), parm);
4914 /* Copy the value into the register. */
4915 if (nominal_mode != passed_mode
4916 || promoted_nominal_mode != promoted_mode)
4919 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4920 mode, by the caller. We now have to convert it to
4921 NOMINAL_MODE, if different. However, PARMREG may be in
4922 a different mode than NOMINAL_MODE if it is being stored
4925 If ENTRY_PARM is a hard register, it might be in a register
4926 not valid for operating in its mode (e.g., an odd-numbered
4927 register for a DFmode). In that case, moves are the only
4928 thing valid, so we can't do a convert from there. This
4929 occurs when the calling sequence allow such misaligned
4932 In addition, the conversion may involve a call, which could
4933 clobber parameters which haven't been copied to pseudo
4934 registers yet. Therefore, we must first copy the parm to
4935 a pseudo reg here, and save the conversion until after all
4936 parameters have been moved. */
4938 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4940 emit_move_insn (tempreg, validize_mem (entry_parm));
4942 push_to_sequence (conversion_insns);
4943 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4945 if (GET_CODE (tempreg) == SUBREG
4946 && GET_MODE (tempreg) == nominal_mode
4947 && GET_CODE (SUBREG_REG (tempreg)) == REG
4948 && nominal_mode == passed_mode
4949 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4950 && GET_MODE_SIZE (GET_MODE (tempreg))
4951 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4953 /* The argument is already sign/zero extended, so note it
4955 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4956 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4959 /* TREE_USED gets set erroneously during expand_assignment. */
4960 save_tree_used = TREE_USED (parm);
4961 expand_assignment (parm,
4962 make_tree (nominal_type, tempreg), 0);
4963 TREE_USED (parm) = save_tree_used;
4964 conversion_insns = get_insns ();
4969 emit_move_insn (parmreg, validize_mem (entry_parm));
4971 /* If we were passed a pointer but the actual value
4972 can safely live in a register, put it in one. */
4973 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4974 /* If by-reference argument was promoted, demote it. */
4975 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4977 && ! DECL_REGISTER (parm))
4978 || TREE_SIDE_EFFECTS (parm)
4979 /* If -ffloat-store specified, don't put explicit
4980 float variables into registers. */
4981 || (flag_float_store
4982 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4984 /* We can't use nominal_mode, because it will have been set to
4985 Pmode above. We must use the actual mode of the parm. */
4986 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4987 mark_user_reg (parmreg);
4988 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4990 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4991 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4992 push_to_sequence (conversion_insns);
4993 emit_move_insn (tempreg, DECL_RTL (parm));
4995 convert_to_mode (GET_MODE (parmreg),
4998 emit_move_insn (parmreg, DECL_RTL (parm));
4999 conversion_insns = get_insns();
5004 emit_move_insn (parmreg, DECL_RTL (parm));
5005 SET_DECL_RTL (parm, parmreg);
5006 /* STACK_PARM is the pointer, not the parm, and PARMREG is
5010 #ifdef FUNCTION_ARG_CALLEE_COPIES
5011 /* If we are passed an arg by reference and it is our responsibility
5012 to make a copy, do it now.
5013 PASSED_TYPE and PASSED mode now refer to the pointer, not the
5014 original argument, so we must recreate them in the call to
5015 FUNCTION_ARG_CALLEE_COPIES. */
5016 /* ??? Later add code to handle the case that if the argument isn't
5017 modified, don't do the copy. */
5019 else if (passed_pointer
5020 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
5021 TYPE_MODE (TREE_TYPE (passed_type)),
5022 TREE_TYPE (passed_type),
5024 && ! TREE_ADDRESSABLE (TREE_TYPE (passed_type)))
5027 tree type = TREE_TYPE (passed_type);
5029 /* This sequence may involve a library call perhaps clobbering
5030 registers that haven't been copied to pseudos yet. */
5032 push_to_sequence (conversion_insns);
5034 if (!COMPLETE_TYPE_P (type)
5035 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5036 /* This is a variable sized object. */
5037 copy = gen_rtx_MEM (BLKmode,
5038 allocate_dynamic_stack_space
5039 (expr_size (parm), NULL_RTX,
5040 TYPE_ALIGN (type)));
5042 copy = assign_stack_temp (TYPE_MODE (type),
5043 int_size_in_bytes (type), 1);
5044 set_mem_attributes (copy, parm, 1);
5046 store_expr (parm, copy, 0);
5047 emit_move_insn (parmreg, XEXP (copy, 0));
5048 conversion_insns = get_insns ();
5052 #endif /* FUNCTION_ARG_CALLEE_COPIES */
5054 /* In any case, record the parm's desired stack location
5055 in case we later discover it must live in the stack.
5057 If it is a COMPLEX value, store the stack location for both
5060 if (GET_CODE (parmreg) == CONCAT)
5061 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
5063 regno = REGNO (parmreg);
5065 if (regno >= max_parm_reg)
5068 int old_max_parm_reg = max_parm_reg;
5070 /* It's slow to expand this one register at a time,
5071 but it's also rare and we need max_parm_reg to be
5072 precisely correct. */
5073 max_parm_reg = regno + 1;
5074 new = ggc_realloc (parm_reg_stack_loc,
5075 max_parm_reg * sizeof (rtx));
5076 memset (new + old_max_parm_reg, 0,
5077 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
5078 parm_reg_stack_loc = new;
5081 if (GET_CODE (parmreg) == CONCAT)
5083 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
5085 regnor = REGNO (gen_realpart (submode, parmreg));
5086 regnoi = REGNO (gen_imagpart (submode, parmreg));
5088 if (stack_parm != 0)
5090 parm_reg_stack_loc[regnor]
5091 = gen_realpart (submode, stack_parm);
5092 parm_reg_stack_loc[regnoi]
5093 = gen_imagpart (submode, stack_parm);
5097 parm_reg_stack_loc[regnor] = 0;
5098 parm_reg_stack_loc[regnoi] = 0;
5102 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
5104 /* Mark the register as eliminable if we did no conversion
5105 and it was copied from memory at a fixed offset,
5106 and the arg pointer was not copied to a pseudo-reg.
5107 If the arg pointer is a pseudo reg or the offset formed
5108 an invalid address, such memory-equivalences
5109 as we make here would screw up life analysis for it. */
5110 if (nominal_mode == passed_mode
5113 && GET_CODE (stack_parm) == MEM
5114 && locate.offset.var == 0
5115 && reg_mentioned_p (virtual_incoming_args_rtx,
5116 XEXP (stack_parm, 0)))
5118 rtx linsn = get_last_insn ();
5121 /* Mark complex types separately. */
5122 if (GET_CODE (parmreg) == CONCAT)
5123 /* Scan backwards for the set of the real and
5125 for (sinsn = linsn; sinsn != 0;
5126 sinsn = prev_nonnote_insn (sinsn))
5128 set = single_set (sinsn);
5130 && SET_DEST (set) == regno_reg_rtx [regnoi])
5132 = gen_rtx_EXPR_LIST (REG_EQUIV,
5133 parm_reg_stack_loc[regnoi],
5136 && SET_DEST (set) == regno_reg_rtx [regnor])
5138 = gen_rtx_EXPR_LIST (REG_EQUIV,
5139 parm_reg_stack_loc[regnor],
5142 else if ((set = single_set (linsn)) != 0
5143 && SET_DEST (set) == parmreg)
5145 = gen_rtx_EXPR_LIST (REG_EQUIV,
5146 stack_parm, REG_NOTES (linsn));
5149 /* For pointer data type, suggest pointer register. */
5150 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5151 mark_reg_pointer (parmreg,
5152 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5154 /* If something wants our address, try to use ADDRESSOF. */
5155 if (TREE_ADDRESSABLE (parm))
5157 /* If we end up putting something into the stack,
5158 fixup_var_refs_insns will need to make a pass over
5159 all the instructions. It looks through the pending
5160 sequences -- but it can't see the ones in the
5161 CONVERSION_INSNS, if they're not on the sequence
5162 stack. So, we go back to that sequence, just so that
5163 the fixups will happen. */
5164 push_to_sequence (conversion_insns);
5165 put_var_into_stack (parm, /*rescan=*/true);
5166 conversion_insns = get_insns ();
5172 /* Value must be stored in the stack slot STACK_PARM
5173 during function execution. */
5175 if (promoted_mode != nominal_mode)
5177 /* Conversion is required. */
5178 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5180 emit_move_insn (tempreg, validize_mem (entry_parm));
5182 push_to_sequence (conversion_insns);
5183 entry_parm = convert_to_mode (nominal_mode, tempreg,
5184 TREE_UNSIGNED (TREE_TYPE (parm)));
5186 /* ??? This may need a big-endian conversion on sparc64. */
5187 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5189 conversion_insns = get_insns ();
5194 if (entry_parm != stack_parm)
5196 if (stack_parm == 0)
5199 = assign_stack_local (GET_MODE (entry_parm),
5200 GET_MODE_SIZE (GET_MODE (entry_parm)),
5202 set_mem_attributes (stack_parm, parm, 1);
5205 if (promoted_mode != nominal_mode)
5207 push_to_sequence (conversion_insns);
5208 emit_move_insn (validize_mem (stack_parm),
5209 validize_mem (entry_parm));
5210 conversion_insns = get_insns ();
5214 emit_move_insn (validize_mem (stack_parm),
5215 validize_mem (entry_parm));
5218 SET_DECL_RTL (parm, stack_parm);
5222 if (SPLIT_COMPLEX_ARGS && fnargs != orig_fnargs)
5224 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
5226 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE)
5231 gen_rtx_CONCAT (DECL_MODE (parm),
5233 DECL_RTL (TREE_CHAIN (fnargs))));
5234 tmp = gen_rtx_CONCAT (DECL_MODE (parm),
5235 DECL_INCOMING_RTL (fnargs),
5236 DECL_INCOMING_RTL (TREE_CHAIN (fnargs)));
5237 set_decl_incoming_rtl (parm, tmp);
5238 fnargs = TREE_CHAIN (fnargs);
5242 SET_DECL_RTL (parm, DECL_RTL (fnargs));
5243 set_decl_incoming_rtl (parm, DECL_INCOMING_RTL (fnargs));
5245 fnargs = TREE_CHAIN (fnargs);
5249 /* Output all parameter conversion instructions (possibly including calls)
5250 now that all parameters have been copied out of hard registers. */
5251 emit_insn (conversion_insns);
5253 /* If we are receiving a struct value address as the first argument, set up
5254 the RTL for the function result. As this might require code to convert
5255 the transmitted address to Pmode, we do this here to ensure that possible
5256 preliminary conversions of the address have been emitted already. */
5257 if (function_result_decl)
5259 tree result = DECL_RESULT (fndecl);
5260 rtx addr = DECL_RTL (function_result_decl);
5263 addr = convert_memory_address (Pmode, addr);
5264 x = gen_rtx_MEM (DECL_MODE (result), addr);
5265 set_mem_attributes (x, result, 1);
5266 SET_DECL_RTL (result, x);
5269 last_parm_insn = get_last_insn ();
5271 current_function_args_size = stack_args_size.constant;
5273 /* Adjust function incoming argument size for alignment and
5276 #ifdef REG_PARM_STACK_SPACE
5277 #ifndef MAYBE_REG_PARM_STACK_SPACE
5278 current_function_args_size = MAX (current_function_args_size,
5279 REG_PARM_STACK_SPACE (fndecl));
5283 current_function_args_size
5284 = ((current_function_args_size + STACK_BYTES - 1)
5285 / STACK_BYTES) * STACK_BYTES;
5287 #ifdef ARGS_GROW_DOWNWARD
5288 current_function_arg_offset_rtx
5289 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5290 : expand_expr (size_diffop (stack_args_size.var,
5291 size_int (-stack_args_size.constant)),
5292 NULL_RTX, VOIDmode, 0));
5294 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5297 /* See how many bytes, if any, of its args a function should try to pop
5300 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5301 current_function_args_size);
5303 /* For stdarg.h function, save info about
5304 regs and stack space used by the named args. */
5306 current_function_args_info = args_so_far;
5308 /* Set the rtx used for the function return value. Put this in its
5309 own variable so any optimizers that need this information don't have
5310 to include tree.h. Do this here so it gets done when an inlined
5311 function gets output. */
5313 current_function_return_rtx
5314 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5315 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5317 /* If scalar return value was computed in a pseudo-reg, or was a named
5318 return value that got dumped to the stack, copy that to the hard
5320 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5322 tree decl_result = DECL_RESULT (fndecl);
5323 rtx decl_rtl = DECL_RTL (decl_result);
5325 if (REG_P (decl_rtl)
5326 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5327 : DECL_REGISTER (decl_result))
5331 #ifdef FUNCTION_OUTGOING_VALUE
5332 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5335 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5338 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5339 /* The delay slot scheduler assumes that current_function_return_rtx
5340 holds the hard register containing the return value, not a
5341 temporary pseudo. */
5342 current_function_return_rtx = real_decl_rtl;
5347 /* If ARGS contains entries with complex types, split the entry into two
5348 entries of the component type. Return a new list of substitutions are
5349 needed, else the old list. */
5352 split_complex_args (tree args)
5356 /* Before allocating memory, check for the common case of no complex. */
5357 for (p = args; p; p = TREE_CHAIN (p))
5358 if (TREE_CODE (TREE_TYPE (p)) == COMPLEX_TYPE)
5363 args = copy_list (args);
5365 for (p = args; p; p = TREE_CHAIN (p))
5367 tree type = TREE_TYPE (p);
5368 if (TREE_CODE (type) == COMPLEX_TYPE)
5371 tree subtype = TREE_TYPE (type);
5373 /* Rewrite the PARM_DECL's type with its component. */
5374 TREE_TYPE (p) = subtype;
5375 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
5376 DECL_MODE (p) = VOIDmode;
5377 DECL_SIZE (p) = NULL;
5378 DECL_SIZE_UNIT (p) = NULL;
5381 /* Build a second synthetic decl. */
5382 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
5383 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
5384 layout_decl (decl, 0);
5386 /* Splice it in; skip the new decl. */
5387 TREE_CHAIN (decl) = TREE_CHAIN (p);
5388 TREE_CHAIN (p) = decl;
5396 /* Indicate whether REGNO is an incoming argument to the current function
5397 that was promoted to a wider mode. If so, return the RTX for the
5398 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5399 that REGNO is promoted from and whether the promotion was signed or
5403 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
5407 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5408 arg = TREE_CHAIN (arg))
5409 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5410 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5411 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5413 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5414 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5416 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5417 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5418 && mode != DECL_MODE (arg))
5420 *pmode = DECL_MODE (arg);
5421 *punsignedp = unsignedp;
5422 return DECL_INCOMING_RTL (arg);
5430 /* Compute the size and offset from the start of the stacked arguments for a
5431 parm passed in mode PASSED_MODE and with type TYPE.
5433 INITIAL_OFFSET_PTR points to the current offset into the stacked
5436 The starting offset and size for this parm are returned in
5437 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5438 nonzero, the offset is that of stack slot, which is returned in
5439 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5440 padding required from the initial offset ptr to the stack slot.
5442 IN_REGS is nonzero if the argument will be passed in registers. It will
5443 never be set if REG_PARM_STACK_SPACE is not defined.
5445 FNDECL is the function in which the argument was defined.
5447 There are two types of rounding that are done. The first, controlled by
5448 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5449 list to be aligned to the specific boundary (in bits). This rounding
5450 affects the initial and starting offsets, but not the argument size.
5452 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5453 optionally rounds the size of the parm to PARM_BOUNDARY. The
5454 initial offset is not affected by this rounding, while the size always
5455 is and the starting offset may be. */
5457 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5458 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5459 callers pass in the total size of args so far as
5460 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5463 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
5464 int partial, tree fndecl ATTRIBUTE_UNUSED,
5465 struct args_size *initial_offset_ptr,
5466 struct locate_and_pad_arg_data *locate)
5469 enum direction where_pad;
5471 int reg_parm_stack_space = 0;
5472 int part_size_in_regs;
5474 #ifdef REG_PARM_STACK_SPACE
5475 #ifdef MAYBE_REG_PARM_STACK_SPACE
5476 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5478 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5481 /* If we have found a stack parm before we reach the end of the
5482 area reserved for registers, skip that area. */
5485 if (reg_parm_stack_space > 0)
5487 if (initial_offset_ptr->var)
5489 initial_offset_ptr->var
5490 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5491 ssize_int (reg_parm_stack_space));
5492 initial_offset_ptr->constant = 0;
5494 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5495 initial_offset_ptr->constant = reg_parm_stack_space;
5498 #endif /* REG_PARM_STACK_SPACE */
5500 part_size_in_regs = 0;
5501 if (reg_parm_stack_space == 0)
5502 part_size_in_regs = ((partial * UNITS_PER_WORD)
5503 / (PARM_BOUNDARY / BITS_PER_UNIT)
5504 * (PARM_BOUNDARY / BITS_PER_UNIT));
5507 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5508 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5509 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5510 locate->where_pad = where_pad;
5512 #ifdef ARGS_GROW_DOWNWARD
5513 locate->slot_offset.constant = -initial_offset_ptr->constant;
5514 if (initial_offset_ptr->var)
5515 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
5516 initial_offset_ptr->var);
5520 if (where_pad != none
5521 && (!host_integerp (sizetree, 1)
5522 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5523 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5524 SUB_PARM_SIZE (locate->slot_offset, s2);
5527 locate->slot_offset.constant += part_size_in_regs;
5530 #ifdef REG_PARM_STACK_SPACE
5531 || REG_PARM_STACK_SPACE (fndecl) > 0
5534 pad_to_arg_alignment (&locate->slot_offset, boundary,
5535 &locate->alignment_pad);
5537 locate->size.constant = (-initial_offset_ptr->constant
5538 - locate->slot_offset.constant);
5539 if (initial_offset_ptr->var)
5540 locate->size.var = size_binop (MINUS_EXPR,
5541 size_binop (MINUS_EXPR,
5543 initial_offset_ptr->var),
5544 locate->slot_offset.var);
5546 /* Pad_below needs the pre-rounded size to know how much to pad
5548 locate->offset = locate->slot_offset;
5549 if (where_pad == downward)
5550 pad_below (&locate->offset, passed_mode, sizetree);
5552 #else /* !ARGS_GROW_DOWNWARD */
5554 #ifdef REG_PARM_STACK_SPACE
5555 || REG_PARM_STACK_SPACE (fndecl) > 0
5558 pad_to_arg_alignment (initial_offset_ptr, boundary,
5559 &locate->alignment_pad);
5560 locate->slot_offset = *initial_offset_ptr;
5562 #ifdef PUSH_ROUNDING
5563 if (passed_mode != BLKmode)
5564 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5567 /* Pad_below needs the pre-rounded size to know how much to pad below
5568 so this must be done before rounding up. */
5569 locate->offset = locate->slot_offset;
5570 if (where_pad == downward)
5571 pad_below (&locate->offset, passed_mode, sizetree);
5573 if (where_pad != none
5574 && (!host_integerp (sizetree, 1)
5575 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5576 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5578 ADD_PARM_SIZE (locate->size, sizetree);
5580 locate->size.constant -= part_size_in_regs;
5581 #endif /* ARGS_GROW_DOWNWARD */
5584 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5585 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5588 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
5589 struct args_size *alignment_pad)
5591 tree save_var = NULL_TREE;
5592 HOST_WIDE_INT save_constant = 0;
5593 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5594 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
5596 #ifdef SPARC_STACK_BOUNDARY_HACK
5597 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
5598 higher than the real alignment of %sp. However, when it does this,
5599 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
5600 This is a temporary hack while the sparc port is fixed. */
5601 if (SPARC_STACK_BOUNDARY_HACK)
5605 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5607 save_var = offset_ptr->var;
5608 save_constant = offset_ptr->constant;
5611 alignment_pad->var = NULL_TREE;
5612 alignment_pad->constant = 0;
5614 if (boundary > BITS_PER_UNIT)
5616 if (offset_ptr->var)
5618 tree sp_offset_tree = ssize_int (sp_offset);
5619 tree offset = size_binop (PLUS_EXPR,
5620 ARGS_SIZE_TREE (*offset_ptr),
5622 #ifdef ARGS_GROW_DOWNWARD
5623 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
5625 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
5628 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
5629 /* ARGS_SIZE_TREE includes constant term. */
5630 offset_ptr->constant = 0;
5631 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5632 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5637 offset_ptr->constant = -sp_offset +
5638 #ifdef ARGS_GROW_DOWNWARD
5639 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5641 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5643 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5644 alignment_pad->constant = offset_ptr->constant - save_constant;
5650 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
5652 if (passed_mode != BLKmode)
5654 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5655 offset_ptr->constant
5656 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5657 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5658 - GET_MODE_SIZE (passed_mode));
5662 if (TREE_CODE (sizetree) != INTEGER_CST
5663 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5665 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5666 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5668 ADD_PARM_SIZE (*offset_ptr, s2);
5669 SUB_PARM_SIZE (*offset_ptr, sizetree);
5674 /* Walk the tree of blocks describing the binding levels within a function
5675 and warn about uninitialized variables.
5676 This is done after calling flow_analysis and before global_alloc
5677 clobbers the pseudo-regs to hard regs. */
5680 uninitialized_vars_warning (tree block)
5683 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5685 if (warn_uninitialized
5686 && TREE_CODE (decl) == VAR_DECL
5687 /* These warnings are unreliable for and aggregates
5688 because assigning the fields one by one can fail to convince
5689 flow.c that the entire aggregate was initialized.
5690 Unions are troublesome because members may be shorter. */
5691 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5692 && DECL_RTL (decl) != 0
5693 && GET_CODE (DECL_RTL (decl)) == REG
5694 /* Global optimizations can make it difficult to determine if a
5695 particular variable has been initialized. However, a VAR_DECL
5696 with a nonzero DECL_INITIAL had an initializer, so do not
5697 claim it is potentially uninitialized.
5699 When the DECL_INITIAL is NULL call the language hook to tell us
5700 if we want to warn. */
5701 && (DECL_INITIAL (decl) == NULL_TREE || lang_hooks.decl_uninit (decl))
5702 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5703 warning ("%J'%D' might be used uninitialized in this function",
5706 && TREE_CODE (decl) == VAR_DECL
5707 && DECL_RTL (decl) != 0
5708 && GET_CODE (DECL_RTL (decl)) == REG
5709 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5710 warning ("%Jvariable '%D' might be clobbered by `longjmp' or `vfork'",
5713 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5714 uninitialized_vars_warning (sub);
5717 /* Do the appropriate part of uninitialized_vars_warning
5718 but for arguments instead of local variables. */
5721 setjmp_args_warning (void)
5724 for (decl = DECL_ARGUMENTS (current_function_decl);
5725 decl; decl = TREE_CHAIN (decl))
5726 if (DECL_RTL (decl) != 0
5727 && GET_CODE (DECL_RTL (decl)) == REG
5728 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5729 warning ("%Jargument '%D' might be clobbered by `longjmp' or `vfork'",
5733 /* If this function call setjmp, put all vars into the stack
5734 unless they were declared `register'. */
5737 setjmp_protect (tree block)
5740 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5741 if ((TREE_CODE (decl) == VAR_DECL
5742 || TREE_CODE (decl) == PARM_DECL)
5743 && DECL_RTL (decl) != 0
5744 && (GET_CODE (DECL_RTL (decl)) == REG
5745 || (GET_CODE (DECL_RTL (decl)) == MEM
5746 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5747 /* If this variable came from an inline function, it must be
5748 that its life doesn't overlap the setjmp. If there was a
5749 setjmp in the function, it would already be in memory. We
5750 must exclude such variable because their DECL_RTL might be
5751 set to strange things such as virtual_stack_vars_rtx. */
5752 && ! DECL_FROM_INLINE (decl)
5754 #ifdef NON_SAVING_SETJMP
5755 /* If longjmp doesn't restore the registers,
5756 don't put anything in them. */
5760 ! DECL_REGISTER (decl)))
5761 put_var_into_stack (decl, /*rescan=*/true);
5762 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5763 setjmp_protect (sub);
5766 /* Like the previous function, but for args instead of local variables. */
5769 setjmp_protect_args (void)
5772 for (decl = DECL_ARGUMENTS (current_function_decl);
5773 decl; decl = TREE_CHAIN (decl))
5774 if ((TREE_CODE (decl) == VAR_DECL
5775 || TREE_CODE (decl) == PARM_DECL)
5776 && DECL_RTL (decl) != 0
5777 && (GET_CODE (DECL_RTL (decl)) == REG
5778 || (GET_CODE (DECL_RTL (decl)) == MEM
5779 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5781 /* If longjmp doesn't restore the registers,
5782 don't put anything in them. */
5783 #ifdef NON_SAVING_SETJMP
5787 ! DECL_REGISTER (decl)))
5788 put_var_into_stack (decl, /*rescan=*/true);
5791 /* Return the context-pointer register corresponding to DECL,
5792 or 0 if it does not need one. */
5795 lookup_static_chain (tree decl)
5797 tree context = decl_function_context (decl);
5801 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5804 /* We treat inline_function_decl as an alias for the current function
5805 because that is the inline function whose vars, types, etc.
5806 are being merged into the current function.
5807 See expand_inline_function. */
5808 if (context == current_function_decl || context == inline_function_decl)
5809 return virtual_stack_vars_rtx;
5811 for (link = context_display; link; link = TREE_CHAIN (link))
5812 if (TREE_PURPOSE (link) == context)
5813 return RTL_EXPR_RTL (TREE_VALUE (link));
5818 /* Convert a stack slot address ADDR for variable VAR
5819 (from a containing function)
5820 into an address valid in this function (using a static chain). */
5823 fix_lexical_addr (rtx addr, tree var)
5826 HOST_WIDE_INT displacement;
5827 tree context = decl_function_context (var);
5828 struct function *fp;
5831 /* If this is the present function, we need not do anything. */
5832 if (context == current_function_decl || context == inline_function_decl)
5835 fp = find_function_data (context);
5837 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5838 addr = XEXP (XEXP (addr, 0), 0);
5840 /* Decode given address as base reg plus displacement. */
5841 if (GET_CODE (addr) == REG)
5842 basereg = addr, displacement = 0;
5843 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5844 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5848 /* We accept vars reached via the containing function's
5849 incoming arg pointer and via its stack variables pointer. */
5850 if (basereg == fp->internal_arg_pointer)
5852 /* If reached via arg pointer, get the arg pointer value
5853 out of that function's stack frame.
5855 There are two cases: If a separate ap is needed, allocate a
5856 slot in the outer function for it and dereference it that way.
5857 This is correct even if the real ap is actually a pseudo.
5858 Otherwise, just adjust the offset from the frame pointer to
5861 #ifdef NEED_SEPARATE_AP
5864 addr = get_arg_pointer_save_area (fp);
5865 addr = fix_lexical_addr (XEXP (addr, 0), var);
5866 addr = memory_address (Pmode, addr);
5868 base = gen_rtx_MEM (Pmode, addr);
5869 set_mem_alias_set (base, get_frame_alias_set ());
5870 base = copy_to_reg (base);
5872 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5873 base = lookup_static_chain (var);
5877 else if (basereg == virtual_stack_vars_rtx)
5879 /* This is the same code as lookup_static_chain, duplicated here to
5880 avoid an extra call to decl_function_context. */
5883 for (link = context_display; link; link = TREE_CHAIN (link))
5884 if (TREE_PURPOSE (link) == context)
5886 base = RTL_EXPR_RTL (TREE_VALUE (link));
5894 /* Use same offset, relative to appropriate static chain or argument
5896 return plus_constant (base, displacement);
5899 /* Return the address of the trampoline for entering nested fn FUNCTION.
5900 If necessary, allocate a trampoline (in the stack frame)
5901 and emit rtl to initialize its contents (at entry to this function). */
5904 trampoline_address (tree function)
5909 struct function *fp;
5912 /* Find an existing trampoline and return it. */
5913 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5914 if (TREE_PURPOSE (link) == function)
5916 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5918 for (fp = outer_function_chain; fp; fp = fp->outer)
5919 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5920 if (TREE_PURPOSE (link) == function)
5922 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5924 return adjust_trampoline_addr (tramp);
5927 /* None exists; we must make one. */
5929 /* Find the `struct function' for the function containing FUNCTION. */
5931 fn_context = decl_function_context (function);
5932 if (fn_context != current_function_decl
5933 && fn_context != inline_function_decl)
5934 fp = find_function_data (fn_context);
5936 /* Allocate run-time space for this trampoline. */
5937 /* If rounding needed, allocate extra space
5938 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5939 #define TRAMPOLINE_REAL_SIZE \
5940 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5941 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5943 /* Record the trampoline for reuse and note it for later initialization
5944 by expand_function_end. */
5947 rtlexp = make_node (RTL_EXPR);
5948 RTL_EXPR_RTL (rtlexp) = tramp;
5949 fp->x_trampoline_list = tree_cons (function, rtlexp,
5950 fp->x_trampoline_list);
5954 /* Make the RTL_EXPR node temporary, not momentary, so that the
5955 trampoline_list doesn't become garbage. */
5956 rtlexp = make_node (RTL_EXPR);
5958 RTL_EXPR_RTL (rtlexp) = tramp;
5959 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5962 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5963 return adjust_trampoline_addr (tramp);
5966 /* Given a trampoline address,
5967 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5970 round_trampoline_addr (rtx tramp)
5972 /* Round address up to desired boundary. */
5973 rtx temp = gen_reg_rtx (Pmode);
5974 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5975 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5977 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5978 temp, 0, OPTAB_LIB_WIDEN);
5979 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5980 temp, 0, OPTAB_LIB_WIDEN);
5985 /* Given a trampoline address, round it then apply any
5986 platform-specific adjustments so that the result can be used for a
5990 adjust_trampoline_addr (rtx tramp)
5992 tramp = round_trampoline_addr (tramp);
5993 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5994 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5999 /* Put all this function's BLOCK nodes including those that are chained
6000 onto the first block into a vector, and return it.
6001 Also store in each NOTE for the beginning or end of a block
6002 the index of that block in the vector.
6003 The arguments are BLOCK, the chain of top-level blocks of the function,
6004 and INSNS, the insn chain of the function. */
6007 identify_blocks (void)
6010 tree *block_vector, *last_block_vector;
6012 tree block = DECL_INITIAL (current_function_decl);
6017 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
6018 depth-first order. */
6019 block_vector = get_block_vector (block, &n_blocks);
6020 block_stack = xmalloc (n_blocks * sizeof (tree));
6022 last_block_vector = identify_blocks_1 (get_insns (),
6024 block_vector + n_blocks,
6027 /* If we didn't use all of the subblocks, we've misplaced block notes. */
6028 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
6029 if (0 && last_block_vector != block_vector + n_blocks)
6032 free (block_vector);
6036 /* Subroutine of identify_blocks. Do the block substitution on the
6037 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
6039 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
6040 BLOCK_VECTOR is incremented for each block seen. */
6043 identify_blocks_1 (rtx insns, tree *block_vector, tree *end_block_vector,
6044 tree *orig_block_stack)
6047 tree *block_stack = orig_block_stack;
6049 for (insn = insns; insn; insn = NEXT_INSN (insn))
6051 if (GET_CODE (insn) == NOTE)
6053 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6057 /* If there are more block notes than BLOCKs, something
6059 if (block_vector == end_block_vector)
6062 b = *block_vector++;
6063 NOTE_BLOCK (insn) = b;
6066 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6068 /* If there are more NOTE_INSN_BLOCK_ENDs than
6069 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
6070 if (block_stack == orig_block_stack)
6073 NOTE_BLOCK (insn) = *--block_stack;
6076 else if (GET_CODE (insn) == CALL_INSN
6077 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6079 rtx cp = PATTERN (insn);
6081 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
6082 end_block_vector, block_stack);
6084 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
6085 end_block_vector, block_stack);
6087 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
6088 end_block_vector, block_stack);
6092 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
6093 something is badly wrong. */
6094 if (block_stack != orig_block_stack)
6097 return block_vector;
6100 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
6101 and create duplicate blocks. */
6102 /* ??? Need an option to either create block fragments or to create
6103 abstract origin duplicates of a source block. It really depends
6104 on what optimization has been performed. */
6107 reorder_blocks (void)
6109 tree block = DECL_INITIAL (current_function_decl);
6110 varray_type block_stack;
6112 if (block == NULL_TREE)
6115 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
6117 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
6118 reorder_blocks_0 (block);
6120 /* Prune the old trees away, so that they don't get in the way. */
6121 BLOCK_SUBBLOCKS (block) = NULL_TREE;
6122 BLOCK_CHAIN (block) = NULL_TREE;
6124 /* Recreate the block tree from the note nesting. */
6125 reorder_blocks_1 (get_insns (), block, &block_stack);
6126 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
6128 /* Remove deleted blocks from the block fragment chains. */
6129 reorder_fix_fragments (block);
6132 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
6135 reorder_blocks_0 (tree block)
6139 TREE_ASM_WRITTEN (block) = 0;
6140 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
6141 block = BLOCK_CHAIN (block);
6146 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack)
6150 for (insn = insns; insn; insn = NEXT_INSN (insn))
6152 if (GET_CODE (insn) == NOTE)
6154 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6156 tree block = NOTE_BLOCK (insn);
6158 /* If we have seen this block before, that means it now
6159 spans multiple address regions. Create a new fragment. */
6160 if (TREE_ASM_WRITTEN (block))
6162 tree new_block = copy_node (block);
6165 origin = (BLOCK_FRAGMENT_ORIGIN (block)
6166 ? BLOCK_FRAGMENT_ORIGIN (block)
6168 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
6169 BLOCK_FRAGMENT_CHAIN (new_block)
6170 = BLOCK_FRAGMENT_CHAIN (origin);
6171 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
6173 NOTE_BLOCK (insn) = new_block;
6177 BLOCK_SUBBLOCKS (block) = 0;
6178 TREE_ASM_WRITTEN (block) = 1;
6179 /* When there's only one block for the entire function,
6180 current_block == block and we mustn't do this, it
6181 will cause infinite recursion. */
6182 if (block != current_block)
6184 BLOCK_SUPERCONTEXT (block) = current_block;
6185 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6186 BLOCK_SUBBLOCKS (current_block) = block;
6187 current_block = block;
6189 VARRAY_PUSH_TREE (*p_block_stack, block);
6191 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6193 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6194 VARRAY_POP (*p_block_stack);
6195 BLOCK_SUBBLOCKS (current_block)
6196 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6197 current_block = BLOCK_SUPERCONTEXT (current_block);
6200 else if (GET_CODE (insn) == CALL_INSN
6201 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6203 rtx cp = PATTERN (insn);
6204 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
6206 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6208 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6213 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6214 appears in the block tree, select one of the fragments to become
6215 the new origin block. */
6218 reorder_fix_fragments (tree block)
6222 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6223 tree new_origin = NULL_TREE;
6227 if (! TREE_ASM_WRITTEN (dup_origin))
6229 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6231 /* Find the first of the remaining fragments. There must
6232 be at least one -- the current block. */
6233 while (! TREE_ASM_WRITTEN (new_origin))
6234 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6235 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6238 else if (! dup_origin)
6241 /* Re-root the rest of the fragments to the new origin. In the
6242 case that DUP_ORIGIN was null, that means BLOCK was the origin
6243 of a chain of fragments and we want to remove those fragments
6244 that didn't make it to the output. */
6247 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6252 if (TREE_ASM_WRITTEN (chain))
6254 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6256 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6258 chain = BLOCK_FRAGMENT_CHAIN (chain);
6263 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6264 block = BLOCK_CHAIN (block);
6268 /* Reverse the order of elements in the chain T of blocks,
6269 and return the new head of the chain (old last element). */
6272 blocks_nreverse (tree t)
6274 tree prev = 0, decl, next;
6275 for (decl = t; decl; decl = next)
6277 next = BLOCK_CHAIN (decl);
6278 BLOCK_CHAIN (decl) = prev;
6284 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6285 non-NULL, list them all into VECTOR, in a depth-first preorder
6286 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6290 all_blocks (tree block, tree *vector)
6296 TREE_ASM_WRITTEN (block) = 0;
6298 /* Record this block. */
6300 vector[n_blocks] = block;
6304 /* Record the subblocks, and their subblocks... */
6305 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6306 vector ? vector + n_blocks : 0);
6307 block = BLOCK_CHAIN (block);
6313 /* Return a vector containing all the blocks rooted at BLOCK. The
6314 number of elements in the vector is stored in N_BLOCKS_P. The
6315 vector is dynamically allocated; it is the caller's responsibility
6316 to call `free' on the pointer returned. */
6319 get_block_vector (tree block, int *n_blocks_p)
6323 *n_blocks_p = all_blocks (block, NULL);
6324 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
6325 all_blocks (block, block_vector);
6327 return block_vector;
6330 static GTY(()) int next_block_index = 2;
6332 /* Set BLOCK_NUMBER for all the blocks in FN. */
6335 number_blocks (tree fn)
6341 /* For SDB and XCOFF debugging output, we start numbering the blocks
6342 from 1 within each function, rather than keeping a running
6344 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6345 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6346 next_block_index = 1;
6349 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6351 /* The top-level BLOCK isn't numbered at all. */
6352 for (i = 1; i < n_blocks; ++i)
6353 /* We number the blocks from two. */
6354 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6356 free (block_vector);
6361 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6364 debug_find_var_in_block_tree (tree var, tree block)
6368 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6372 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6374 tree ret = debug_find_var_in_block_tree (var, t);
6382 /* Allocate a function structure for FNDECL and set its contents
6386 allocate_struct_function (tree fndecl)
6390 cfun = ggc_alloc_cleared (sizeof (struct function));
6392 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6394 cfun->stack_alignment_needed = STACK_BOUNDARY;
6395 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6397 current_function_funcdef_no = funcdef_no++;
6399 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6401 init_stmt_for_function ();
6402 init_eh_for_function ();
6404 (*lang_hooks.function.init) (cfun);
6405 if (init_machine_status)
6406 cfun->machine = (*init_machine_status) ();
6411 DECL_SAVED_INSNS (fndecl) = cfun;
6412 cfun->decl = fndecl;
6414 result = DECL_RESULT (fndecl);
6415 if (aggregate_value_p (result, fndecl))
6417 #ifdef PCC_STATIC_STRUCT_RETURN
6418 current_function_returns_pcc_struct = 1;
6420 current_function_returns_struct = 1;
6423 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
6425 current_function_needs_context
6426 = (decl_function_context (current_function_decl) != 0
6427 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6430 /* Reset cfun, and other non-struct-function variables to defaults as
6431 appropriate for emitting rtl at the start of a function. */
6434 prepare_function_start (tree fndecl)
6436 if (fndecl && DECL_SAVED_INSNS (fndecl))
6437 cfun = DECL_SAVED_INSNS (fndecl);
6439 allocate_struct_function (fndecl);
6441 init_varasm_status (cfun);
6444 cse_not_expected = ! optimize;
6446 /* Caller save not needed yet. */
6447 caller_save_needed = 0;
6449 /* We haven't done register allocation yet. */
6452 /* Indicate that we need to distinguish between the return value of the
6453 present function and the return value of a function being called. */
6454 rtx_equal_function_value_matters = 1;
6456 /* Indicate that we have not instantiated virtual registers yet. */
6457 virtuals_instantiated = 0;
6459 /* Indicate that we want CONCATs now. */
6460 generating_concat_p = 1;
6462 /* Indicate we have no need of a frame pointer yet. */
6463 frame_pointer_needed = 0;
6466 /* Initialize the rtl expansion mechanism so that we can do simple things
6467 like generate sequences. This is used to provide a context during global
6468 initialization of some passes. */
6470 init_dummy_function_start (void)
6472 prepare_function_start (NULL);
6475 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6476 and initialize static variables for generating RTL for the statements
6480 init_function_start (tree subr)
6482 prepare_function_start (subr);
6484 /* Within function body, compute a type's size as soon it is laid out. */
6485 immediate_size_expand++;
6487 /* Prevent ever trying to delete the first instruction of a
6488 function. Also tell final how to output a linenum before the
6489 function prologue. Note linenums could be missing, e.g. when
6490 compiling a Java .class file. */
6491 if (DECL_SOURCE_LINE (subr))
6492 emit_line_note (DECL_SOURCE_LOCATION (subr));
6494 /* Make sure first insn is a note even if we don't want linenums.
6495 This makes sure the first insn will never be deleted.
6496 Also, final expects a note to appear there. */
6497 emit_note (NOTE_INSN_DELETED);
6499 /* Warn if this value is an aggregate type,
6500 regardless of which calling convention we are using for it. */
6501 if (warn_aggregate_return
6502 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6503 warning ("function returns an aggregate");
6506 /* Make sure all values used by the optimization passes have sane
6509 init_function_for_compilation (void)
6513 /* No prologue/epilogue insns yet. */
6514 VARRAY_GROW (prologue, 0);
6515 VARRAY_GROW (epilogue, 0);
6516 VARRAY_GROW (sibcall_epilogue, 0);
6519 /* Expand a call to __main at the beginning of a possible main function. */
6521 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6522 #undef HAS_INIT_SECTION
6523 #define HAS_INIT_SECTION
6527 expand_main_function (void)
6529 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6530 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6532 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6536 /* Forcibly align the stack. */
6537 #ifdef STACK_GROWS_DOWNWARD
6538 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6539 stack_pointer_rtx, 1, OPTAB_WIDEN);
6541 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6542 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6543 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6544 stack_pointer_rtx, 1, OPTAB_WIDEN);
6546 if (tmp != stack_pointer_rtx)
6547 emit_move_insn (stack_pointer_rtx, tmp);
6549 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6550 tmp = force_reg (Pmode, const0_rtx);
6551 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6555 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6556 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6559 emit_insn_before (seq, tmp);
6565 #ifndef HAS_INIT_SECTION
6566 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6570 /* The PENDING_SIZES represent the sizes of variable-sized types.
6571 Create RTL for the various sizes now (using temporary variables),
6572 so that we can refer to the sizes from the RTL we are generating
6573 for the current function. The PENDING_SIZES are a TREE_LIST. The
6574 TREE_VALUE of each node is a SAVE_EXPR. */
6577 expand_pending_sizes (tree pending_sizes)
6581 /* Evaluate now the sizes of any types declared among the arguments. */
6582 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6584 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6585 /* Flush the queue in case this parameter declaration has
6591 /* Start the RTL for a new function, and set variables used for
6593 SUBR is the FUNCTION_DECL node.
6594 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6595 the function's parameters, which must be run at any return statement. */
6598 expand_function_start (tree subr, int parms_have_cleanups)
6601 rtx last_ptr = NULL_RTX;
6603 /* Make sure volatile mem refs aren't considered
6604 valid operands of arithmetic insns. */
6605 init_recog_no_volatile ();
6607 current_function_instrument_entry_exit
6608 = (flag_instrument_function_entry_exit
6609 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6611 current_function_profile
6613 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6615 current_function_limit_stack
6616 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6618 /* If function gets a static chain arg, store it in the stack frame.
6619 Do this first, so it gets the first stack slot offset. */
6620 if (current_function_needs_context)
6622 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6624 /* Delay copying static chain if it is not a register to avoid
6625 conflicts with regs used for parameters. */
6626 if (! SMALL_REGISTER_CLASSES
6627 || GET_CODE (static_chain_incoming_rtx) == REG)
6628 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6631 /* If the parameters of this function need cleaning up, get a label
6632 for the beginning of the code which executes those cleanups. This must
6633 be done before doing anything with return_label. */
6634 if (parms_have_cleanups)
6635 cleanup_label = gen_label_rtx ();
6639 /* Make the label for return statements to jump to. Do not special
6640 case machines with special return instructions -- they will be
6641 handled later during jump, ifcvt, or epilogue creation. */
6642 return_label = gen_label_rtx ();
6644 /* Initialize rtx used to return the value. */
6645 /* Do this before assign_parms so that we copy the struct value address
6646 before any library calls that assign parms might generate. */
6648 /* Decide whether to return the value in memory or in a register. */
6649 if (aggregate_value_p (DECL_RESULT (subr), subr))
6651 /* Returning something that won't go in a register. */
6652 rtx value_address = 0;
6654 #ifdef PCC_STATIC_STRUCT_RETURN
6655 if (current_function_returns_pcc_struct)
6657 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6658 value_address = assemble_static_space (size);
6663 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
6664 /* Expect to be passed the address of a place to store the value.
6665 If it is passed as an argument, assign_parms will take care of
6669 value_address = gen_reg_rtx (Pmode);
6670 emit_move_insn (value_address, sv);
6675 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6676 set_mem_attributes (x, DECL_RESULT (subr), 1);
6677 SET_DECL_RTL (DECL_RESULT (subr), x);
6680 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6681 /* If return mode is void, this decl rtl should not be used. */
6682 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6685 /* Compute the return values into a pseudo reg, which we will copy
6686 into the true return register after the cleanups are done. */
6688 /* In order to figure out what mode to use for the pseudo, we
6689 figure out what the mode of the eventual return register will
6690 actually be, and use that. */
6692 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6695 /* Structures that are returned in registers are not aggregate_value_p,
6696 so we may see a PARALLEL or a REG. */
6697 if (REG_P (hard_reg))
6698 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6699 else if (GET_CODE (hard_reg) == PARALLEL)
6700 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6704 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6705 result to the real return register(s). */
6706 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6709 /* Initialize rtx for parameters and local variables.
6710 In some cases this requires emitting insns. */
6712 assign_parms (subr);
6714 /* Copy the static chain now if it wasn't a register. The delay is to
6715 avoid conflicts with the parameter passing registers. */
6717 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6718 if (GET_CODE (static_chain_incoming_rtx) != REG)
6719 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6721 /* The following was moved from init_function_start.
6722 The move is supposed to make sdb output more accurate. */
6723 /* Indicate the beginning of the function body,
6724 as opposed to parm setup. */
6725 emit_note (NOTE_INSN_FUNCTION_BEG);
6727 if (GET_CODE (get_last_insn ()) != NOTE)
6728 emit_note (NOTE_INSN_DELETED);
6729 parm_birth_insn = get_last_insn ();
6731 context_display = 0;
6732 if (current_function_needs_context)
6734 /* Fetch static chain values for containing functions. */
6735 tem = decl_function_context (current_function_decl);
6736 /* Copy the static chain pointer into a pseudo. If we have
6737 small register classes, copy the value from memory if
6738 static_chain_incoming_rtx is a REG. */
6741 /* If the static chain originally came in a register, put it back
6742 there, then move it out in the next insn. The reason for
6743 this peculiar code is to satisfy function integration. */
6744 if (SMALL_REGISTER_CLASSES
6745 && GET_CODE (static_chain_incoming_rtx) == REG)
6746 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6747 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6752 tree rtlexp = make_node (RTL_EXPR);
6754 RTL_EXPR_RTL (rtlexp) = last_ptr;
6755 context_display = tree_cons (tem, rtlexp, context_display);
6756 tem = decl_function_context (tem);
6759 /* Chain through stack frames, assuming pointer to next lexical frame
6760 is found at the place we always store it. */
6761 #ifdef FRAME_GROWS_DOWNWARD
6762 last_ptr = plus_constant (last_ptr,
6763 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6765 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6766 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6767 last_ptr = copy_to_reg (last_ptr);
6769 /* If we are not optimizing, ensure that we know that this
6770 piece of context is live over the entire function. */
6772 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6777 if (current_function_instrument_entry_exit)
6779 rtx fun = DECL_RTL (current_function_decl);
6780 if (GET_CODE (fun) == MEM)
6781 fun = XEXP (fun, 0);
6784 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6786 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6788 hard_frame_pointer_rtx),
6792 if (current_function_profile)
6795 PROFILE_HOOK (current_function_funcdef_no);
6799 /* After the display initializations is where the tail-recursion label
6800 should go, if we end up needing one. Ensure we have a NOTE here
6801 since some things (like trampolines) get placed before this. */
6802 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
6804 /* Evaluate now the sizes of any types declared among the arguments. */
6805 expand_pending_sizes (nreverse (get_pending_sizes ()));
6807 /* Make sure there is a line number after the function entry setup code. */
6808 force_next_line_note ();
6811 /* Undo the effects of init_dummy_function_start. */
6813 expand_dummy_function_end (void)
6815 /* End any sequences that failed to be closed due to syntax errors. */
6816 while (in_sequence_p ())
6819 /* Outside function body, can't compute type's actual size
6820 until next function's body starts. */
6822 free_after_parsing (cfun);
6823 free_after_compilation (cfun);
6827 /* Call DOIT for each hard register used as a return value from
6828 the current function. */
6831 diddle_return_value (void (*doit) (rtx, void *), void *arg)
6833 rtx outgoing = current_function_return_rtx;
6838 if (GET_CODE (outgoing) == REG)
6839 (*doit) (outgoing, arg);
6840 else if (GET_CODE (outgoing) == PARALLEL)
6844 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6846 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6848 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6855 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6857 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6861 clobber_return_register (void)
6863 diddle_return_value (do_clobber_return_reg, NULL);
6865 /* In case we do use pseudo to return value, clobber it too. */
6866 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6868 tree decl_result = DECL_RESULT (current_function_decl);
6869 rtx decl_rtl = DECL_RTL (decl_result);
6870 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6872 do_clobber_return_reg (decl_rtl, NULL);
6878 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6880 emit_insn (gen_rtx_USE (VOIDmode, reg));
6884 use_return_register (void)
6886 diddle_return_value (do_use_return_reg, NULL);
6889 static GTY(()) rtx initial_trampoline;
6891 /* Generate RTL for the end of the current function. */
6894 expand_function_end (void)
6899 finish_expr_for_function ();
6901 /* If arg_pointer_save_area was referenced only from a nested
6902 function, we will not have initialized it yet. Do that now. */
6903 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6904 get_arg_pointer_save_area (cfun);
6906 #ifdef NON_SAVING_SETJMP
6907 /* Don't put any variables in registers if we call setjmp
6908 on a machine that fails to restore the registers. */
6909 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6911 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6912 setjmp_protect (DECL_INITIAL (current_function_decl));
6914 setjmp_protect_args ();
6918 /* Initialize any trampolines required by this function. */
6919 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6921 tree function = TREE_PURPOSE (link);
6922 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6923 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6924 #ifdef TRAMPOLINE_TEMPLATE
6929 #ifdef TRAMPOLINE_TEMPLATE
6930 /* First make sure this compilation has a template for
6931 initializing trampolines. */
6932 if (initial_trampoline == 0)
6935 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6936 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6940 /* Generate insns to initialize the trampoline. */
6942 tramp = round_trampoline_addr (XEXP (tramp, 0));
6943 #ifdef TRAMPOLINE_TEMPLATE
6944 blktramp = replace_equiv_address (initial_trampoline, tramp);
6945 emit_block_move (blktramp, initial_trampoline,
6946 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6948 trampolines_created = 1;
6949 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6953 /* Put those insns at entry to the containing function (this one). */
6954 emit_insn_before (seq, tail_recursion_reentry);
6957 /* If we are doing stack checking and this function makes calls,
6958 do a stack probe at the start of the function to ensure we have enough
6959 space for another stack frame. */
6960 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6964 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6965 if (GET_CODE (insn) == CALL_INSN)
6968 probe_stack_range (STACK_CHECK_PROTECT,
6969 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6972 emit_insn_before (seq, tail_recursion_reentry);
6977 /* Possibly warn about unused parameters. */
6978 if (warn_unused_parameter)
6982 for (decl = DECL_ARGUMENTS (current_function_decl);
6983 decl; decl = TREE_CHAIN (decl))
6984 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6985 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6986 warning ("%Junused parameter '%D'", decl, decl);
6989 /* Delete handlers for nonlocal gotos if nothing uses them. */
6990 if (nonlocal_goto_handler_slots != 0
6991 && ! current_function_has_nonlocal_label)
6994 /* End any sequences that failed to be closed due to syntax errors. */
6995 while (in_sequence_p ())
6998 /* Outside function body, can't compute type's actual size
6999 until next function's body starts. */
7000 immediate_size_expand--;
7002 clear_pending_stack_adjust ();
7003 do_pending_stack_adjust ();
7005 /* Mark the end of the function body.
7006 If control reaches this insn, the function can drop through
7007 without returning a value. */
7008 emit_note (NOTE_INSN_FUNCTION_END);
7010 /* Must mark the last line number note in the function, so that the test
7011 coverage code can avoid counting the last line twice. This just tells
7012 the code to ignore the immediately following line note, since there
7013 already exists a copy of this note somewhere above. This line number
7014 note is still needed for debugging though, so we can't delete it. */
7015 if (flag_test_coverage)
7016 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
7018 /* Output a linenumber for the end of the function.
7019 SDB depends on this. */
7020 force_next_line_note ();
7021 emit_line_note (input_location);
7023 /* Before the return label (if any), clobber the return
7024 registers so that they are not propagated live to the rest of
7025 the function. This can only happen with functions that drop
7026 through; if there had been a return statement, there would
7027 have either been a return rtx, or a jump to the return label.
7029 We delay actual code generation after the current_function_value_rtx
7031 clobber_after = get_last_insn ();
7033 /* Output the label for the actual return from the function,
7034 if one is expected. This happens either because a function epilogue
7035 is used instead of a return instruction, or because a return was done
7036 with a goto in order to run local cleanups, or because of pcc-style
7037 structure returning. */
7039 emit_label (return_label);
7041 if (current_function_instrument_entry_exit)
7043 rtx fun = DECL_RTL (current_function_decl);
7044 if (GET_CODE (fun) == MEM)
7045 fun = XEXP (fun, 0);
7048 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
7050 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
7052 hard_frame_pointer_rtx),
7056 /* Let except.c know where it should emit the call to unregister
7057 the function context for sjlj exceptions. */
7058 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
7059 sjlj_emit_function_exit_after (get_last_insn ());
7061 /* If we had calls to alloca, and this machine needs
7062 an accurate stack pointer to exit the function,
7063 insert some code to save and restore the stack pointer. */
7064 if (! EXIT_IGNORE_STACK
7065 && current_function_calls_alloca)
7069 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
7070 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
7073 /* If scalar return value was computed in a pseudo-reg, or was a named
7074 return value that got dumped to the stack, copy that to the hard
7076 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
7078 tree decl_result = DECL_RESULT (current_function_decl);
7079 rtx decl_rtl = DECL_RTL (decl_result);
7081 if (REG_P (decl_rtl)
7082 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
7083 : DECL_REGISTER (decl_result))
7085 rtx real_decl_rtl = current_function_return_rtx;
7087 /* This should be set in assign_parms. */
7088 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
7091 /* If this is a BLKmode structure being returned in registers,
7092 then use the mode computed in expand_return. Note that if
7093 decl_rtl is memory, then its mode may have been changed,
7094 but that current_function_return_rtx has not. */
7095 if (GET_MODE (real_decl_rtl) == BLKmode)
7096 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
7098 /* If a named return value dumped decl_return to memory, then
7099 we may need to re-do the PROMOTE_MODE signed/unsigned
7101 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
7103 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
7105 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
7106 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7109 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7111 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7113 /* If expand_function_start has created a PARALLEL for decl_rtl,
7114 move the result to the real return registers. Otherwise, do
7115 a group load from decl_rtl for a named return. */
7116 if (GET_CODE (decl_rtl) == PARALLEL)
7117 emit_group_move (real_decl_rtl, decl_rtl);
7119 emit_group_load (real_decl_rtl, decl_rtl,
7120 TREE_TYPE (decl_result),
7121 int_size_in_bytes (TREE_TYPE (decl_result)));
7124 emit_move_insn (real_decl_rtl, decl_rtl);
7128 /* If returning a structure, arrange to return the address of the value
7129 in a place where debuggers expect to find it.
7131 If returning a structure PCC style,
7132 the caller also depends on this value.
7133 And current_function_returns_pcc_struct is not necessarily set. */
7134 if (current_function_returns_struct
7135 || current_function_returns_pcc_struct)
7138 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7139 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7140 #ifdef FUNCTION_OUTGOING_VALUE
7142 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7143 current_function_decl);
7146 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7149 /* Mark this as a function return value so integrate will delete the
7150 assignment and USE below when inlining this function. */
7151 REG_FUNCTION_VALUE_P (outgoing) = 1;
7153 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7154 value_address = convert_memory_address (GET_MODE (outgoing),
7157 emit_move_insn (outgoing, value_address);
7159 /* Show return register used to hold result (in this case the address
7161 current_function_return_rtx = outgoing;
7164 /* If this is an implementation of throw, do what's necessary to
7165 communicate between __builtin_eh_return and the epilogue. */
7166 expand_eh_return ();
7168 /* Emit the actual code to clobber return register. */
7173 clobber_return_register ();
7177 after = emit_insn_after (seq, clobber_after);
7179 if (clobber_after != after)
7180 cfun->x_clobber_return_insn = after;
7183 /* Output the label for the naked return from the function, if one is
7184 expected. This is currently used only by __builtin_return. */
7185 if (naked_return_label)
7186 emit_label (naked_return_label);
7188 /* ??? This should no longer be necessary since stupid is no longer with
7189 us, but there are some parts of the compiler (eg reload_combine, and
7190 sh mach_dep_reorg) that still try and compute their own lifetime info
7191 instead of using the general framework. */
7192 use_return_register ();
7194 /* Fix up any gotos that jumped out to the outermost
7195 binding level of the function.
7196 Must follow emitting RETURN_LABEL. */
7198 /* If you have any cleanups to do at this point,
7199 and they need to create temporary variables,
7200 then you will lose. */
7201 expand_fixups (get_insns ());
7205 get_arg_pointer_save_area (struct function *f)
7207 rtx ret = f->x_arg_pointer_save_area;
7211 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7212 f->x_arg_pointer_save_area = ret;
7215 if (f == cfun && ! f->arg_pointer_save_area_init)
7219 /* Save the arg pointer at the beginning of the function. The
7220 generated stack slot may not be a valid memory address, so we
7221 have to check it and fix it if necessary. */
7223 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7227 push_topmost_sequence ();
7228 emit_insn_after (seq, get_insns ());
7229 pop_topmost_sequence ();
7235 /* Extend a vector that records the INSN_UIDs of INSNS
7236 (a list of one or more insns). */
7239 record_insns (rtx insns, varray_type *vecp)
7246 while (tmp != NULL_RTX)
7249 tmp = NEXT_INSN (tmp);
7252 i = VARRAY_SIZE (*vecp);
7253 VARRAY_GROW (*vecp, i + len);
7255 while (tmp != NULL_RTX)
7257 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7259 tmp = NEXT_INSN (tmp);
7263 /* Set the locator of the insn chain starting at INSN to LOC. */
7265 set_insn_locators (rtx insn, int loc)
7267 while (insn != NULL_RTX)
7270 INSN_LOCATOR (insn) = loc;
7271 insn = NEXT_INSN (insn);
7275 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7276 be running after reorg, SEQUENCE rtl is possible. */
7279 contains (rtx insn, varray_type vec)
7283 if (GET_CODE (insn) == INSN
7284 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7287 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7288 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7289 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7295 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7296 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7303 prologue_epilogue_contains (rtx insn)
7305 if (contains (insn, prologue))
7307 if (contains (insn, epilogue))
7313 sibcall_epilogue_contains (rtx insn)
7315 if (sibcall_epilogue)
7316 return contains (insn, sibcall_epilogue);
7321 /* Insert gen_return at the end of block BB. This also means updating
7322 block_for_insn appropriately. */
7325 emit_return_into_block (basic_block bb, rtx line_note)
7327 emit_jump_insn_after (gen_return (), BB_END (bb));
7329 emit_note_copy_after (line_note, PREV_INSN (BB_END (bb)));
7331 #endif /* HAVE_return */
7333 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7335 /* These functions convert the epilogue into a variant that does not modify the
7336 stack pointer. This is used in cases where a function returns an object
7337 whose size is not known until it is computed. The called function leaves the
7338 object on the stack, leaves the stack depressed, and returns a pointer to
7341 What we need to do is track all modifications and references to the stack
7342 pointer, deleting the modifications and changing the references to point to
7343 the location the stack pointer would have pointed to had the modifications
7346 These functions need to be portable so we need to make as few assumptions
7347 about the epilogue as we can. However, the epilogue basically contains
7348 three things: instructions to reset the stack pointer, instructions to
7349 reload registers, possibly including the frame pointer, and an
7350 instruction to return to the caller.
7352 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7353 We also make no attempt to validate the insns we make since if they are
7354 invalid, we probably can't do anything valid. The intent is that these
7355 routines get "smarter" as more and more machines start to use them and
7356 they try operating on different epilogues.
7358 We use the following structure to track what the part of the epilogue that
7359 we've already processed has done. We keep two copies of the SP equivalence,
7360 one for use during the insn we are processing and one for use in the next
7361 insn. The difference is because one part of a PARALLEL may adjust SP
7362 and the other may use it. */
7366 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7367 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7368 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7369 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7370 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7371 should be set to once we no longer need
7373 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences
7377 static void handle_epilogue_set (rtx, struct epi_info *);
7378 static void update_epilogue_consts (rtx, rtx, void *);
7379 static void emit_equiv_load (struct epi_info *);
7381 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7382 no modifications to the stack pointer. Return the new list of insns. */
7385 keep_stack_depressed (rtx insns)
7388 struct epi_info info;
7391 /* If the epilogue is just a single instruction, it must be OK as is. */
7392 if (NEXT_INSN (insns) == NULL_RTX)
7395 /* Otherwise, start a sequence, initialize the information we have, and
7396 process all the insns we were given. */
7399 info.sp_equiv_reg = stack_pointer_rtx;
7401 info.equiv_reg_src = 0;
7403 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
7404 info.const_equiv[j] = 0;
7408 while (insn != NULL_RTX)
7410 next = NEXT_INSN (insn);
7419 /* If this insn references the register that SP is equivalent to and
7420 we have a pending load to that register, we must force out the load
7421 first and then indicate we no longer know what SP's equivalent is. */
7422 if (info.equiv_reg_src != 0
7423 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7425 emit_equiv_load (&info);
7426 info.sp_equiv_reg = 0;
7429 info.new_sp_equiv_reg = info.sp_equiv_reg;
7430 info.new_sp_offset = info.sp_offset;
7432 /* If this is a (RETURN) and the return address is on the stack,
7433 update the address and change to an indirect jump. */
7434 if (GET_CODE (PATTERN (insn)) == RETURN
7435 || (GET_CODE (PATTERN (insn)) == PARALLEL
7436 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7438 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7440 HOST_WIDE_INT offset = 0;
7441 rtx jump_insn, jump_set;
7443 /* If the return address is in a register, we can emit the insn
7444 unchanged. Otherwise, it must be a MEM and we see what the
7445 base register and offset are. In any case, we have to emit any
7446 pending load to the equivalent reg of SP, if any. */
7447 if (GET_CODE (retaddr) == REG)
7449 emit_equiv_load (&info);
7454 else if (GET_CODE (retaddr) == MEM
7455 && GET_CODE (XEXP (retaddr, 0)) == REG)
7456 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7457 else if (GET_CODE (retaddr) == MEM
7458 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7459 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7460 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7462 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7463 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7468 /* If the base of the location containing the return pointer
7469 is SP, we must update it with the replacement address. Otherwise,
7470 just build the necessary MEM. */
7471 retaddr = plus_constant (base, offset);
7472 if (base == stack_pointer_rtx)
7473 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7474 plus_constant (info.sp_equiv_reg,
7477 retaddr = gen_rtx_MEM (Pmode, retaddr);
7479 /* If there is a pending load to the equivalent register for SP
7480 and we reference that register, we must load our address into
7481 a scratch register and then do that load. */
7482 if (info.equiv_reg_src
7483 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7488 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7489 if (HARD_REGNO_MODE_OK (regno, Pmode)
7490 && !fixed_regs[regno]
7491 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7492 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7494 && !refers_to_regno_p (regno,
7495 regno + hard_regno_nregs[regno]
7497 info.equiv_reg_src, NULL)
7498 && info.const_equiv[regno] == 0)
7501 if (regno == FIRST_PSEUDO_REGISTER)
7504 reg = gen_rtx_REG (Pmode, regno);
7505 emit_move_insn (reg, retaddr);
7509 emit_equiv_load (&info);
7510 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7512 /* Show the SET in the above insn is a RETURN. */
7513 jump_set = single_set (jump_insn);
7517 SET_IS_RETURN_P (jump_set) = 1;
7520 /* If SP is not mentioned in the pattern and its equivalent register, if
7521 any, is not modified, just emit it. Otherwise, if neither is set,
7522 replace the reference to SP and emit the insn. If none of those are
7523 true, handle each SET individually. */
7524 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7525 && (info.sp_equiv_reg == stack_pointer_rtx
7526 || !reg_set_p (info.sp_equiv_reg, insn)))
7528 else if (! reg_set_p (stack_pointer_rtx, insn)
7529 && (info.sp_equiv_reg == stack_pointer_rtx
7530 || !reg_set_p (info.sp_equiv_reg, insn)))
7532 if (! validate_replace_rtx (stack_pointer_rtx,
7533 plus_constant (info.sp_equiv_reg,
7540 else if (GET_CODE (PATTERN (insn)) == SET)
7541 handle_epilogue_set (PATTERN (insn), &info);
7542 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7544 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7545 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7546 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7551 info.sp_equiv_reg = info.new_sp_equiv_reg;
7552 info.sp_offset = info.new_sp_offset;
7554 /* Now update any constants this insn sets. */
7555 note_stores (PATTERN (insn), update_epilogue_consts, &info);
7559 insns = get_insns ();
7564 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7565 structure that contains information about what we've seen so far. We
7566 process this SET by either updating that data or by emitting one or
7570 handle_epilogue_set (rtx set, struct epi_info *p)
7572 /* First handle the case where we are setting SP. Record what it is being
7573 set from. If unknown, abort. */
7574 if (reg_set_p (stack_pointer_rtx, set))
7576 if (SET_DEST (set) != stack_pointer_rtx)
7579 if (GET_CODE (SET_SRC (set)) == PLUS)
7581 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7582 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7583 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7584 else if (GET_CODE (XEXP (SET_SRC (set), 1)) == REG
7585 && REGNO (XEXP (SET_SRC (set), 1)) < FIRST_PSEUDO_REGISTER
7586 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))] != 0)
7588 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
7593 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7595 /* If we are adjusting SP, we adjust from the old data. */
7596 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7598 p->new_sp_equiv_reg = p->sp_equiv_reg;
7599 p->new_sp_offset += p->sp_offset;
7602 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7608 /* Next handle the case where we are setting SP's equivalent register.
7609 If we already have a value to set it to, abort. We could update, but
7610 there seems little point in handling that case. Note that we have
7611 to allow for the case where we are setting the register set in
7612 the previous part of a PARALLEL inside a single insn. But use the
7613 old offset for any updates within this insn. We must allow for the case
7614 where the register is being set in a different (usually wider) mode than
7616 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7618 if (p->equiv_reg_src != 0
7619 || GET_CODE (p->new_sp_equiv_reg) != REG
7620 || GET_CODE (SET_DEST (set)) != REG
7621 || GET_MODE_BITSIZE (GET_MODE (SET_DEST (set))) > BITS_PER_WORD
7622 || REGNO (p->new_sp_equiv_reg) != REGNO (SET_DEST (set)))
7626 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7627 plus_constant (p->sp_equiv_reg,
7631 /* Otherwise, replace any references to SP in the insn to its new value
7632 and emit the insn. */
7635 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7636 plus_constant (p->sp_equiv_reg,
7638 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7639 plus_constant (p->sp_equiv_reg,
7645 /* Update the tracking information for registers set to constants. */
7648 update_epilogue_consts (rtx dest, rtx x, void *data)
7650 struct epi_info *p = (struct epi_info *) data;
7652 if (GET_CODE (dest) != REG || REGNO (dest) >= FIRST_PSEUDO_REGISTER)
7654 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x))
7655 || GET_CODE (SET_SRC (x)) != CONST_INT)
7656 p->const_equiv[REGNO (dest)] = 0;
7658 p->const_equiv[REGNO (dest)] = SET_SRC (x);
7661 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7664 emit_equiv_load (struct epi_info *p)
7666 if (p->equiv_reg_src != 0)
7668 rtx dest = p->sp_equiv_reg;
7670 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest))
7671 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src),
7672 REGNO (p->sp_equiv_reg));
7674 emit_move_insn (dest, p->equiv_reg_src);
7675 p->equiv_reg_src = 0;
7680 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7681 this into place with notes indicating where the prologue ends and where
7682 the epilogue begins. Update the basic block information when possible. */
7685 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
7689 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7692 #ifdef HAVE_prologue
7693 rtx prologue_end = NULL_RTX;
7695 #if defined (HAVE_epilogue) || defined(HAVE_return)
7696 rtx epilogue_end = NULL_RTX;
7699 #ifdef HAVE_prologue
7703 seq = gen_prologue ();
7706 /* Retain a map of the prologue insns. */
7707 record_insns (seq, &prologue);
7708 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
7712 set_insn_locators (seq, prologue_locator);
7714 /* Can't deal with multiple successors of the entry block
7715 at the moment. Function should always have at least one
7717 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7720 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7725 /* If the exit block has no non-fake predecessors, we don't need
7727 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7728 if ((e->flags & EDGE_FAKE) == 0)
7734 if (optimize && HAVE_return)
7736 /* If we're allowed to generate a simple return instruction,
7737 then by definition we don't need a full epilogue. Examine
7738 the block that falls through to EXIT. If it does not
7739 contain any code, examine its predecessors and try to
7740 emit (conditional) return instructions. */
7746 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7747 if (e->flags & EDGE_FALLTHRU)
7753 /* Verify that there are no active instructions in the last block. */
7754 label = BB_END (last);
7755 while (label && GET_CODE (label) != CODE_LABEL)
7757 if (active_insn_p (label))
7759 label = PREV_INSN (label);
7762 if (BB_HEAD (last) == label && GET_CODE (label) == CODE_LABEL)
7764 rtx epilogue_line_note = NULL_RTX;
7766 /* Locate the line number associated with the closing brace,
7767 if we can find one. */
7768 for (seq = get_last_insn ();
7769 seq && ! active_insn_p (seq);
7770 seq = PREV_INSN (seq))
7771 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7773 epilogue_line_note = seq;
7777 for (e = last->pred; e; e = e_next)
7779 basic_block bb = e->src;
7782 e_next = e->pred_next;
7783 if (bb == ENTRY_BLOCK_PTR)
7787 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7790 /* If we have an unconditional jump, we can replace that
7791 with a simple return instruction. */
7792 if (simplejump_p (jump))
7794 emit_return_into_block (bb, epilogue_line_note);
7798 /* If we have a conditional jump, we can try to replace
7799 that with a conditional return instruction. */
7800 else if (condjump_p (jump))
7802 if (! redirect_jump (jump, 0, 0))
7805 /* If this block has only one successor, it both jumps
7806 and falls through to the fallthru block, so we can't
7808 if (bb->succ->succ_next == NULL)
7814 /* Fix up the CFG for the successful change we just made. */
7815 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7818 /* Emit a return insn for the exit fallthru block. Whether
7819 this is still reachable will be determined later. */
7821 emit_barrier_after (BB_END (last));
7822 emit_return_into_block (last, epilogue_line_note);
7823 epilogue_end = BB_END (last);
7824 last->succ->flags &= ~EDGE_FALLTHRU;
7829 #ifdef HAVE_epilogue
7832 /* Find the edge that falls through to EXIT. Other edges may exist
7833 due to RETURN instructions, but those don't need epilogues.
7834 There really shouldn't be a mixture -- either all should have
7835 been converted or none, however... */
7837 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7838 if (e->flags & EDGE_FALLTHRU)
7844 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
7846 seq = gen_epilogue ();
7848 #ifdef INCOMING_RETURN_ADDR_RTX
7849 /* If this function returns with the stack depressed and we can support
7850 it, massage the epilogue to actually do that. */
7851 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7852 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7853 seq = keep_stack_depressed (seq);
7856 emit_jump_insn (seq);
7858 /* Retain a map of the epilogue insns. */
7859 record_insns (seq, &epilogue);
7860 set_insn_locators (seq, epilogue_locator);
7865 insert_insn_on_edge (seq, e);
7872 commit_edge_insertions ();
7874 #ifdef HAVE_sibcall_epilogue
7875 /* Emit sibling epilogues before any sibling call sites. */
7876 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7878 basic_block bb = e->src;
7879 rtx insn = BB_END (bb);
7883 if (GET_CODE (insn) != CALL_INSN
7884 || ! SIBLING_CALL_P (insn))
7888 emit_insn (gen_sibcall_epilogue ());
7892 /* Retain a map of the epilogue insns. Used in life analysis to
7893 avoid getting rid of sibcall epilogue insns. Do this before we
7894 actually emit the sequence. */
7895 record_insns (seq, &sibcall_epilogue);
7896 set_insn_locators (seq, epilogue_locator);
7898 i = PREV_INSN (insn);
7899 newinsn = emit_insn_before (seq, insn);
7903 #ifdef HAVE_prologue
7904 /* This is probably all useless now that we use locators. */
7909 /* GDB handles `break f' by setting a breakpoint on the first
7910 line note after the prologue. Which means (1) that if
7911 there are line number notes before where we inserted the
7912 prologue we should move them, and (2) we should generate a
7913 note before the end of the first basic block, if there isn't
7916 ??? This behavior is completely broken when dealing with
7917 multiple entry functions. We simply place the note always
7918 into first basic block and let alternate entry points
7922 for (insn = prologue_end; insn; insn = prev)
7924 prev = PREV_INSN (insn);
7925 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7927 /* Note that we cannot reorder the first insn in the
7928 chain, since rest_of_compilation relies on that
7929 remaining constant. */
7932 reorder_insns (insn, insn, prologue_end);
7936 /* Find the last line number note in the first block. */
7937 for (insn = BB_END (ENTRY_BLOCK_PTR->next_bb);
7938 insn != prologue_end && insn;
7939 insn = PREV_INSN (insn))
7940 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7943 /* If we didn't find one, make a copy of the first line number
7947 for (insn = next_active_insn (prologue_end);
7949 insn = PREV_INSN (insn))
7950 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7952 emit_note_copy_after (insn, prologue_end);
7958 #ifdef HAVE_epilogue
7963 /* Similarly, move any line notes that appear after the epilogue.
7964 There is no need, however, to be quite so anal about the existence
7966 for (insn = epilogue_end; insn; insn = next)
7968 next = NEXT_INSN (insn);
7969 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7970 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7976 /* Reposition the prologue-end and epilogue-begin notes after instruction
7977 scheduling and delayed branch scheduling. */
7980 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
7982 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7983 rtx insn, last, note;
7986 if ((len = VARRAY_SIZE (prologue)) > 0)
7990 /* Scan from the beginning until we reach the last prologue insn.
7991 We apparently can't depend on basic_block_{head,end} after
7993 for (insn = f; insn; insn = NEXT_INSN (insn))
7995 if (GET_CODE (insn) == NOTE)
7997 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
8000 else if (contains (insn, prologue))
8010 /* Find the prologue-end note if we haven't already, and
8011 move it to just after the last prologue insn. */
8014 for (note = last; (note = NEXT_INSN (note));)
8015 if (GET_CODE (note) == NOTE
8016 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
8020 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
8021 if (GET_CODE (last) == CODE_LABEL)
8022 last = NEXT_INSN (last);
8023 reorder_insns (note, note, last);
8027 if ((len = VARRAY_SIZE (epilogue)) > 0)
8031 /* Scan from the end until we reach the first epilogue insn.
8032 We apparently can't depend on basic_block_{head,end} after
8034 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
8036 if (GET_CODE (insn) == NOTE)
8038 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
8041 else if (contains (insn, epilogue))
8051 /* Find the epilogue-begin note if we haven't already, and
8052 move it to just before the first epilogue insn. */
8055 for (note = insn; (note = PREV_INSN (note));)
8056 if (GET_CODE (note) == NOTE
8057 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
8061 if (PREV_INSN (last) != note)
8062 reorder_insns (note, note, PREV_INSN (last));
8065 #endif /* HAVE_prologue or HAVE_epilogue */
8068 /* Called once, at initialization, to initialize function.c. */
8071 init_function_once (void)
8073 VARRAY_INT_INIT (prologue, 0, "prologue");
8074 VARRAY_INT_INIT (epilogue, 0, "epilogue");
8075 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
8078 /* Returns the name of the current function. */
8080 current_function_name (void)
8082 return (*lang_hooks.decl_printable_name) (cfun->decl, 2);
8085 #include "gt-function.h"