1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002 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
26 /* This file handles the generation of rtl code from tree structure
27 at the level of the function as a whole.
28 It creates the rtl expressions for parameters and auto variables
29 and has full responsibility for allocating stack slots.
31 `expand_function_start' is called at the beginning of a function,
32 before the function body is parsed, and `expand_function_end' is
33 called after parsing the body.
35 Call `assign_stack_local' to allocate a stack slot for a local variable.
36 This is usually done during the RTL generation for the function body,
37 but it can also be done in the reload pass when a pseudo-register does
38 not get a hard register.
40 Call `put_var_into_stack' when you learn, belatedly, that a variable
41 previously given a pseudo-register must in fact go in the stack.
42 This function changes the DECL_RTL to be a stack slot instead of a reg
43 then scans all the RTL instructions so far generated to correct them. */
55 #include "hard-reg-set.h"
56 #include "insn-config.h"
59 #include "basic-block.h"
65 #include "integrate.h"
67 #ifndef TRAMPOLINE_ALIGNMENT
68 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
71 #ifndef LOCAL_ALIGNMENT
72 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
75 /* Some systems use __main in a way incompatible with its use in gcc, in these
76 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
77 give the same symbol without quotes for an alternative entry point. You
78 must define both, or neither. */
80 #define NAME__MAIN "__main"
81 #define SYMBOL__MAIN __main
84 /* Round a value to the lowest integer less than it that is a multiple of
85 the required alignment. Avoid using division in case the value is
86 negative. Assume the alignment is a power of two. */
87 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
89 /* Similar, but round to the next highest integer that meets the
91 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
93 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
94 during rtl generation. If they are different register numbers, this is
95 always true. It may also be true if
96 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
97 generation. See fix_lexical_addr for details. */
99 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
100 #define NEED_SEPARATE_AP
103 /* Nonzero if function being compiled doesn't contain any calls
104 (ignoring the prologue and epilogue). This is set prior to
105 local register allocation and is valid for the remaining
107 int current_function_is_leaf;
109 /* Nonzero if function being compiled doesn't contain any instructions
110 that can throw an exception. This is set prior to final. */
112 int current_function_nothrow;
114 /* Nonzero if function being compiled doesn't modify the stack pointer
115 (ignoring the prologue and epilogue). This is only valid after
116 life_analysis has run. */
117 int current_function_sp_is_unchanging;
119 /* Nonzero if the function being compiled is a leaf function which only
120 uses leaf registers. This is valid after reload (specifically after
121 sched2) and is useful only if the port defines LEAF_REGISTERS. */
122 int current_function_uses_only_leaf_regs;
124 /* Nonzero once virtual register instantiation has been done.
125 assign_stack_local uses frame_pointer_rtx when this is nonzero.
126 calls.c:emit_library_call_value_1 uses it to set up
127 post-instantiation libcalls. */
128 int virtuals_instantiated;
130 /* Assign unique numbers to labels generated for profiling. */
131 static int profile_label_no;
133 /* These variables hold pointers to functions to create and destroy
134 target specific, per-function data structures. */
135 void (*init_machine_status) PARAMS ((struct function *));
136 void (*free_machine_status) PARAMS ((struct function *));
137 /* This variable holds a pointer to a function to register any
138 data items in the target specific, per-function data structure
139 that will need garbage collection. */
140 void (*mark_machine_status) PARAMS ((struct function *));
142 /* Likewise, but for language-specific data. */
143 void (*init_lang_status) PARAMS ((struct function *));
144 void (*save_lang_status) PARAMS ((struct function *));
145 void (*restore_lang_status) PARAMS ((struct function *));
146 void (*mark_lang_status) PARAMS ((struct function *));
147 void (*free_lang_status) PARAMS ((struct function *));
149 /* The FUNCTION_DECL for an inline function currently being expanded. */
150 tree inline_function_decl;
152 /* The currently compiled function. */
153 struct function *cfun = 0;
155 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
156 static varray_type prologue;
157 static varray_type epilogue;
159 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
161 static varray_type sibcall_epilogue;
163 /* In order to evaluate some expressions, such as function calls returning
164 structures in memory, we need to temporarily allocate stack locations.
165 We record each allocated temporary in the following structure.
167 Associated with each temporary slot is a nesting level. When we pop up
168 one level, all temporaries associated with the previous level are freed.
169 Normally, all temporaries are freed after the execution of the statement
170 in which they were created. However, if we are inside a ({...}) grouping,
171 the result may be in a temporary and hence must be preserved. If the
172 result could be in a temporary, we preserve it if we can determine which
173 one it is in. If we cannot determine which temporary may contain the
174 result, all temporaries are preserved. A temporary is preserved by
175 pretending it was allocated at the previous nesting level.
177 Automatic variables are also assigned temporary slots, at the nesting
178 level where they are defined. They are marked a "kept" so that
179 free_temp_slots will not free them. */
183 /* Points to next temporary slot. */
184 struct temp_slot *next;
185 /* The rtx to used to reference the slot. */
187 /* The rtx used to represent the address if not the address of the
188 slot above. May be an EXPR_LIST if multiple addresses exist. */
190 /* The alignment (in bits) of the slot. */
192 /* The size, in units, of the slot. */
194 /* The type of the object in the slot, or zero if it doesn't correspond
195 to a type. We use this to determine whether a slot can be reused.
196 It can be reused if objects of the type of the new slot will always
197 conflict with objects of the type of the old slot. */
199 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
201 /* Non-zero if this temporary is currently in use. */
203 /* Non-zero if this temporary has its address taken. */
205 /* Nesting level at which this slot is being used. */
207 /* Non-zero if this should survive a call to free_temp_slots. */
209 /* The offset of the slot from the frame_pointer, including extra space
210 for alignment. This info is for combine_temp_slots. */
211 HOST_WIDE_INT base_offset;
212 /* The size of the slot, including extra space for alignment. This
213 info is for combine_temp_slots. */
214 HOST_WIDE_INT full_size;
217 /* This structure is used to record MEMs or pseudos used to replace VAR, any
218 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
219 maintain this list in case two operands of an insn were required to match;
220 in that case we must ensure we use the same replacement. */
222 struct fixup_replacement
226 struct fixup_replacement *next;
229 struct insns_for_mem_entry
231 /* The KEY in HE will be a MEM. */
232 struct hash_entry he;
233 /* These are the INSNS which reference the MEM. */
237 /* Forward declarations. */
239 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
240 int, struct function *));
241 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
242 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
243 enum machine_mode, enum machine_mode,
244 int, unsigned int, int,
245 struct hash_table *));
246 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
248 struct hash_table *));
249 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int, rtx,
250 struct hash_table *));
251 static struct fixup_replacement
252 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
253 static void fixup_var_refs_insns PARAMS ((rtx, rtx, enum machine_mode,
255 static void fixup_var_refs_insns_with_hash
256 PARAMS ((struct hash_table *, rtx,
257 enum machine_mode, int, rtx));
258 static void fixup_var_refs_insn PARAMS ((rtx, rtx, enum machine_mode,
260 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
261 struct fixup_replacement **, rtx));
262 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, enum machine_mode, int));
263 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, enum machine_mode,
265 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
266 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
267 static void instantiate_decls PARAMS ((tree, int));
268 static void instantiate_decls_1 PARAMS ((tree, int));
269 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
270 static rtx instantiate_new_reg PARAMS ((rtx, HOST_WIDE_INT *));
271 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
272 static void delete_handlers PARAMS ((void));
273 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
274 struct args_size *));
275 #ifndef ARGS_GROW_DOWNWARD
276 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
279 static rtx round_trampoline_addr PARAMS ((rtx));
280 static rtx adjust_trampoline_addr PARAMS ((rtx));
281 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
282 static void reorder_blocks_0 PARAMS ((tree));
283 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
284 static void reorder_fix_fragments PARAMS ((tree));
285 static tree blocks_nreverse PARAMS ((tree));
286 static int all_blocks PARAMS ((tree, tree *));
287 static tree *get_block_vector PARAMS ((tree, int *));
288 extern tree debug_find_var_in_block_tree PARAMS ((tree, tree));
289 /* We always define `record_insns' even if its not used so that we
290 can always export `prologue_epilogue_contains'. */
291 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
292 static int contains PARAMS ((rtx, varray_type));
294 static void emit_return_into_block PARAMS ((basic_block, rtx));
296 static void put_addressof_into_stack PARAMS ((rtx, struct hash_table *));
297 static bool purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
298 struct hash_table *));
299 static void purge_single_hard_subreg_set PARAMS ((rtx));
300 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
301 static rtx keep_stack_depressed PARAMS ((rtx));
303 static int is_addressof PARAMS ((rtx *, void *));
304 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
307 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
308 static bool insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
309 static int insns_for_mem_walk PARAMS ((rtx *, void *));
310 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
311 static void mark_function_status PARAMS ((struct function *));
312 static void maybe_mark_struct_function PARAMS ((void *));
313 static void prepare_function_start PARAMS ((void));
314 static void do_clobber_return_reg PARAMS ((rtx, void *));
315 static void do_use_return_reg PARAMS ((rtx, void *));
317 /* Pointer to chain of `struct function' for containing functions. */
318 static struct function *outer_function_chain;
320 /* Given a function decl for a containing function,
321 return the `struct function' for it. */
324 find_function_data (decl)
329 for (p = outer_function_chain; p; p = p->outer)
336 /* Save the current context for compilation of a nested function.
337 This is called from language-specific code. The caller should use
338 the save_lang_status callback to save any language-specific state,
339 since this function knows only about language-independent
343 push_function_context_to (context)
350 if (context == current_function_decl)
351 cfun->contains_functions = 1;
354 struct function *containing = find_function_data (context);
355 containing->contains_functions = 1;
360 init_dummy_function_start ();
363 p->outer = outer_function_chain;
364 outer_function_chain = p;
365 p->fixup_var_refs_queue = 0;
367 if (save_lang_status)
368 (*save_lang_status) (p);
374 push_function_context ()
376 push_function_context_to (current_function_decl);
379 /* Restore the last saved context, at the end of a nested function.
380 This function is called from language-specific code. */
383 pop_function_context_from (context)
384 tree context ATTRIBUTE_UNUSED;
386 struct function *p = outer_function_chain;
387 struct var_refs_queue *queue;
390 outer_function_chain = p->outer;
392 current_function_decl = p->decl;
395 restore_emit_status (p);
397 if (restore_lang_status)
398 (*restore_lang_status) (p);
400 /* Finish doing put_var_into_stack for any of our variables which became
401 addressable during the nested function. If only one entry has to be
402 fixed up, just do that one. Otherwise, first make a list of MEMs that
403 are not to be unshared. */
404 if (p->fixup_var_refs_queue == 0)
406 else if (p->fixup_var_refs_queue->next == 0)
407 fixup_var_refs (p->fixup_var_refs_queue->modified,
408 p->fixup_var_refs_queue->promoted_mode,
409 p->fixup_var_refs_queue->unsignedp,
410 p->fixup_var_refs_queue->modified, 0);
415 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
416 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
418 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
419 fixup_var_refs (queue->modified, queue->promoted_mode,
420 queue->unsignedp, list, 0);
424 p->fixup_var_refs_queue = 0;
426 /* Reset variables that have known state during rtx generation. */
427 rtx_equal_function_value_matters = 1;
428 virtuals_instantiated = 0;
429 generating_concat_p = 1;
433 pop_function_context ()
435 pop_function_context_from (current_function_decl);
438 /* Clear out all parts of the state in F that can safely be discarded
439 after the function has been parsed, but not compiled, to let
440 garbage collection reclaim the memory. */
443 free_after_parsing (f)
446 /* f->expr->forced_labels is used by code generation. */
447 /* f->emit->regno_reg_rtx is used by code generation. */
448 /* f->varasm is used by code generation. */
449 /* f->eh->eh_return_stub_label is used by code generation. */
451 if (free_lang_status)
452 (*free_lang_status) (f);
453 free_stmt_status (f);
456 /* Clear out all parts of the state in F that can safely be discarded
457 after the function has been compiled, to let garbage collection
458 reclaim the memory. */
461 free_after_compilation (f)
465 free_expr_status (f);
466 free_emit_status (f);
467 free_varasm_status (f);
469 if (free_machine_status)
470 (*free_machine_status) (f);
472 if (f->x_parm_reg_stack_loc)
473 free (f->x_parm_reg_stack_loc);
475 f->x_temp_slots = NULL;
476 f->arg_offset_rtx = NULL;
477 f->return_rtx = NULL;
478 f->internal_arg_pointer = NULL;
479 f->x_nonlocal_labels = NULL;
480 f->x_nonlocal_goto_handler_slots = NULL;
481 f->x_nonlocal_goto_handler_labels = NULL;
482 f->x_nonlocal_goto_stack_level = NULL;
483 f->x_cleanup_label = NULL;
484 f->x_return_label = NULL;
485 f->x_save_expr_regs = NULL;
486 f->x_stack_slot_list = NULL;
487 f->x_rtl_expr_chain = NULL;
488 f->x_tail_recursion_label = NULL;
489 f->x_tail_recursion_reentry = NULL;
490 f->x_arg_pointer_save_area = NULL;
491 f->x_clobber_return_insn = NULL;
492 f->x_context_display = NULL;
493 f->x_trampoline_list = NULL;
494 f->x_parm_birth_insn = NULL;
495 f->x_last_parm_insn = NULL;
496 f->x_parm_reg_stack_loc = NULL;
497 f->fixup_var_refs_queue = NULL;
498 f->original_arg_vector = NULL;
499 f->original_decl_initial = NULL;
500 f->inl_last_parm_insn = NULL;
501 f->epilogue_delay_list = NULL;
504 /* Allocate fixed slots in the stack frame of the current function. */
506 /* Return size needed for stack frame based on slots so far allocated in
508 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
509 the caller may have to do that. */
512 get_func_frame_size (f)
515 #ifdef FRAME_GROWS_DOWNWARD
516 return -f->x_frame_offset;
518 return f->x_frame_offset;
522 /* Return size needed for stack frame based on slots so far allocated.
523 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
524 the caller may have to do that. */
528 return get_func_frame_size (cfun);
531 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
532 with machine mode MODE.
534 ALIGN controls the amount of alignment for the address of the slot:
535 0 means according to MODE,
536 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
537 positive specifies alignment boundary in bits.
539 We do not round to stack_boundary here.
541 FUNCTION specifies the function to allocate in. */
544 assign_stack_local_1 (mode, size, align, function)
545 enum machine_mode mode;
548 struct function *function;
551 int bigend_correction = 0;
553 int frame_off, frame_alignment, frame_phase;
560 alignment = BIGGEST_ALIGNMENT;
562 alignment = GET_MODE_ALIGNMENT (mode);
564 /* Allow the target to (possibly) increase the alignment of this
566 type = type_for_mode (mode, 0);
568 alignment = LOCAL_ALIGNMENT (type, alignment);
570 alignment /= BITS_PER_UNIT;
572 else if (align == -1)
574 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
575 size = CEIL_ROUND (size, alignment);
578 alignment = align / BITS_PER_UNIT;
580 #ifdef FRAME_GROWS_DOWNWARD
581 function->x_frame_offset -= size;
584 /* Ignore alignment we can't do with expected alignment of the boundary. */
585 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
586 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
588 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
589 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
591 /* Calculate how many bytes the start of local variables is off from
593 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
594 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
595 frame_phase = frame_off ? frame_alignment - frame_off : 0;
597 /* Round frame offset to that alignment.
598 We must be careful here, since FRAME_OFFSET might be negative and
599 division with a negative dividend isn't as well defined as we might
600 like. So we instead assume that ALIGNMENT is a power of two and
601 use logical operations which are unambiguous. */
602 #ifdef FRAME_GROWS_DOWNWARD
603 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment) + frame_phase;
605 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset - frame_phase, alignment) + frame_phase;
608 /* On a big-endian machine, if we are allocating more space than we will use,
609 use the least significant bytes of those that are allocated. */
610 if (BYTES_BIG_ENDIAN && mode != BLKmode)
611 bigend_correction = size - GET_MODE_SIZE (mode);
613 /* If we have already instantiated virtual registers, return the actual
614 address relative to the frame pointer. */
615 if (function == cfun && virtuals_instantiated)
616 addr = plus_constant (frame_pointer_rtx,
617 (frame_offset + bigend_correction
618 + STARTING_FRAME_OFFSET));
620 addr = plus_constant (virtual_stack_vars_rtx,
621 function->x_frame_offset + bigend_correction);
623 #ifndef FRAME_GROWS_DOWNWARD
624 function->x_frame_offset += size;
627 x = gen_rtx_MEM (mode, addr);
629 function->x_stack_slot_list
630 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
635 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
639 assign_stack_local (mode, size, align)
640 enum machine_mode mode;
644 return assign_stack_local_1 (mode, size, align, cfun);
647 /* Allocate a temporary stack slot and record it for possible later
650 MODE is the machine mode to be given to the returned rtx.
652 SIZE is the size in units of the space required. We do no rounding here
653 since assign_stack_local will do any required rounding.
655 KEEP is 1 if this slot is to be retained after a call to
656 free_temp_slots. Automatic variables for a block are allocated
657 with this flag. KEEP is 2 if we allocate a longer term temporary,
658 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
659 if we are to allocate something at an inner level to be treated as
660 a variable in the block (e.g., a SAVE_EXPR).
662 TYPE is the type that will be used for the stack slot. */
665 assign_stack_temp_for_type (mode, size, keep, type)
666 enum machine_mode mode;
672 struct temp_slot *p, *best_p = 0;
674 /* If SIZE is -1 it means that somebody tried to allocate a temporary
675 of a variable size. */
680 align = BIGGEST_ALIGNMENT;
682 align = GET_MODE_ALIGNMENT (mode);
685 type = type_for_mode (mode, 0);
688 align = LOCAL_ALIGNMENT (type, align);
690 /* Try to find an available, already-allocated temporary of the proper
691 mode which meets the size and alignment requirements. Choose the
692 smallest one with the closest alignment. */
693 for (p = temp_slots; p; p = p->next)
694 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
696 && objects_must_conflict_p (p->type, type)
697 && (best_p == 0 || best_p->size > p->size
698 || (best_p->size == p->size && best_p->align > p->align)))
700 if (p->align == align && p->size == size)
708 /* Make our best, if any, the one to use. */
711 /* If there are enough aligned bytes left over, make them into a new
712 temp_slot so that the extra bytes don't get wasted. Do this only
713 for BLKmode slots, so that we can be sure of the alignment. */
714 if (GET_MODE (best_p->slot) == BLKmode)
716 int alignment = best_p->align / BITS_PER_UNIT;
717 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
719 if (best_p->size - rounded_size >= alignment)
721 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
722 p->in_use = p->addr_taken = 0;
723 p->size = best_p->size - rounded_size;
724 p->base_offset = best_p->base_offset + rounded_size;
725 p->full_size = best_p->full_size - rounded_size;
726 p->slot = gen_rtx_MEM (BLKmode,
727 plus_constant (XEXP (best_p->slot, 0),
729 p->align = best_p->align;
732 p->type = best_p->type;
733 p->next = temp_slots;
736 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
739 best_p->size = rounded_size;
740 best_p->full_size = rounded_size;
747 /* If we still didn't find one, make a new temporary. */
750 HOST_WIDE_INT frame_offset_old = frame_offset;
752 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
754 /* We are passing an explicit alignment request to assign_stack_local.
755 One side effect of that is assign_stack_local will not round SIZE
756 to ensure the frame offset remains suitably aligned.
758 So for requests which depended on the rounding of SIZE, we go ahead
759 and round it now. We also make sure ALIGNMENT is at least
760 BIGGEST_ALIGNMENT. */
761 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
763 p->slot = assign_stack_local (mode,
765 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
771 /* The following slot size computation is necessary because we don't
772 know the actual size of the temporary slot until assign_stack_local
773 has performed all the frame alignment and size rounding for the
774 requested temporary. Note that extra space added for alignment
775 can be either above or below this stack slot depending on which
776 way the frame grows. We include the extra space if and only if it
777 is above this slot. */
778 #ifdef FRAME_GROWS_DOWNWARD
779 p->size = frame_offset_old - frame_offset;
784 /* Now define the fields used by combine_temp_slots. */
785 #ifdef FRAME_GROWS_DOWNWARD
786 p->base_offset = frame_offset;
787 p->full_size = frame_offset_old - frame_offset;
789 p->base_offset = frame_offset_old;
790 p->full_size = frame_offset - frame_offset_old;
793 p->next = temp_slots;
799 p->rtl_expr = seq_rtl_expr;
804 p->level = target_temp_slot_level;
809 p->level = var_temp_slot_level;
814 p->level = temp_slot_level;
818 /* We may be reusing an old slot, so clear any MEM flags that may have been
820 RTX_UNCHANGING_P (p->slot) = 0;
821 MEM_IN_STRUCT_P (p->slot) = 0;
822 MEM_SCALAR_P (p->slot) = 0;
823 MEM_VOLATILE_P (p->slot) = 0;
824 set_mem_alias_set (p->slot, 0);
826 /* If we know the alias set for the memory that will be used, use
827 it. If there's no TYPE, then we don't know anything about the
828 alias set for the memory. */
829 set_mem_alias_set (p->slot, type ? get_alias_set (type) : 0);
830 set_mem_align (p->slot, align);
832 /* If a type is specified, set the relevant flags. */
835 RTX_UNCHANGING_P (p->slot) = TYPE_READONLY (type);
836 MEM_VOLATILE_P (p->slot) = TYPE_VOLATILE (type);
837 MEM_SET_IN_STRUCT_P (p->slot, AGGREGATE_TYPE_P (type));
843 /* Allocate a temporary stack slot and record it for possible later
844 reuse. First three arguments are same as in preceding function. */
847 assign_stack_temp (mode, size, keep)
848 enum machine_mode mode;
852 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
855 /* Assign a temporary.
856 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
857 and so that should be used in error messages. In either case, we
858 allocate of the given type.
859 KEEP is as for assign_stack_temp.
860 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
861 it is 0 if a register is OK.
862 DONT_PROMOTE is 1 if we should not promote values in register
866 assign_temp (type_or_decl, keep, memory_required, dont_promote)
870 int dont_promote ATTRIBUTE_UNUSED;
873 enum machine_mode mode;
874 #ifndef PROMOTE_FOR_CALL_ONLY
878 if (DECL_P (type_or_decl))
879 decl = type_or_decl, type = TREE_TYPE (decl);
881 decl = NULL, type = type_or_decl;
883 mode = TYPE_MODE (type);
884 #ifndef PROMOTE_FOR_CALL_ONLY
885 unsignedp = TREE_UNSIGNED (type);
888 if (mode == BLKmode || memory_required)
890 HOST_WIDE_INT size = int_size_in_bytes (type);
893 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
894 problems with allocating the stack space. */
898 /* Unfortunately, we don't yet know how to allocate variable-sized
899 temporaries. However, sometimes we have a fixed upper limit on
900 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
901 instead. This is the case for Chill variable-sized strings. */
902 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
903 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
904 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
905 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
907 /* The size of the temporary may be too large to fit into an integer. */
908 /* ??? Not sure this should happen except for user silliness, so limit
909 this to things that aren't compiler-generated temporaries. The
910 rest of the time we'll abort in assign_stack_temp_for_type. */
911 if (decl && size == -1
912 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
914 error_with_decl (decl, "size of variable `%s' is too large");
918 tmp = assign_stack_temp_for_type (mode, size, keep, type);
922 #ifndef PROMOTE_FOR_CALL_ONLY
924 mode = promote_mode (type, mode, &unsignedp, 0);
927 return gen_reg_rtx (mode);
930 /* Combine temporary stack slots which are adjacent on the stack.
932 This allows for better use of already allocated stack space. This is only
933 done for BLKmode slots because we can be sure that we won't have alignment
934 problems in this case. */
937 combine_temp_slots ()
939 struct temp_slot *p, *q;
940 struct temp_slot *prev_p, *prev_q;
943 /* We can't combine slots, because the information about which slot
944 is in which alias set will be lost. */
945 if (flag_strict_aliasing)
948 /* If there are a lot of temp slots, don't do anything unless
949 high levels of optimization. */
950 if (! flag_expensive_optimizations)
951 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
952 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
955 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
959 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
960 for (q = p->next, prev_q = p; q; q = prev_q->next)
963 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
965 if (p->base_offset + p->full_size == q->base_offset)
967 /* Q comes after P; combine Q into P. */
969 p->full_size += q->full_size;
972 else if (q->base_offset + q->full_size == p->base_offset)
974 /* P comes after Q; combine P into Q. */
976 q->full_size += p->full_size;
981 /* Either delete Q or advance past it. */
983 prev_q->next = q->next;
987 /* Either delete P or advance past it. */
991 prev_p->next = p->next;
993 temp_slots = p->next;
1000 /* Find the temp slot corresponding to the object at address X. */
1002 static struct temp_slot *
1003 find_temp_slot_from_address (x)
1006 struct temp_slot *p;
1009 for (p = temp_slots; p; p = p->next)
1014 else if (XEXP (p->slot, 0) == x
1016 || (GET_CODE (x) == PLUS
1017 && XEXP (x, 0) == virtual_stack_vars_rtx
1018 && GET_CODE (XEXP (x, 1)) == CONST_INT
1019 && INTVAL (XEXP (x, 1)) >= p->base_offset
1020 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
1023 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
1024 for (next = p->address; next; next = XEXP (next, 1))
1025 if (XEXP (next, 0) == x)
1029 /* If we have a sum involving a register, see if it points to a temp
1031 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1032 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1034 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1035 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1041 /* Indicate that NEW is an alternate way of referring to the temp slot
1042 that previously was known by OLD. */
1045 update_temp_slot_address (old, new)
1048 struct temp_slot *p;
1050 if (rtx_equal_p (old, new))
1053 p = find_temp_slot_from_address (old);
1055 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1056 is a register, see if one operand of the PLUS is a temporary
1057 location. If so, NEW points into it. Otherwise, if both OLD and
1058 NEW are a PLUS and if there is a register in common between them.
1059 If so, try a recursive call on those values. */
1062 if (GET_CODE (old) != PLUS)
1065 if (GET_CODE (new) == REG)
1067 update_temp_slot_address (XEXP (old, 0), new);
1068 update_temp_slot_address (XEXP (old, 1), new);
1071 else if (GET_CODE (new) != PLUS)
1074 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1075 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1076 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1077 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1078 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1079 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1080 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1081 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1086 /* Otherwise add an alias for the temp's address. */
1087 else if (p->address == 0)
1091 if (GET_CODE (p->address) != EXPR_LIST)
1092 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1094 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1098 /* If X could be a reference to a temporary slot, mark the fact that its
1099 address was taken. */
1102 mark_temp_addr_taken (x)
1105 struct temp_slot *p;
1110 /* If X is not in memory or is at a constant address, it cannot be in
1111 a temporary slot. */
1112 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1115 p = find_temp_slot_from_address (XEXP (x, 0));
1120 /* If X could be a reference to a temporary slot, mark that slot as
1121 belonging to the to one level higher than the current level. If X
1122 matched one of our slots, just mark that one. Otherwise, we can't
1123 easily predict which it is, so upgrade all of them. Kept slots
1124 need not be touched.
1126 This is called when an ({...}) construct occurs and a statement
1127 returns a value in memory. */
1130 preserve_temp_slots (x)
1133 struct temp_slot *p = 0;
1135 /* If there is no result, we still might have some objects whose address
1136 were taken, so we need to make sure they stay around. */
1139 for (p = temp_slots; p; p = p->next)
1140 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1146 /* If X is a register that is being used as a pointer, see if we have
1147 a temporary slot we know it points to. To be consistent with
1148 the code below, we really should preserve all non-kept slots
1149 if we can't find a match, but that seems to be much too costly. */
1150 if (GET_CODE (x) == REG && REG_POINTER (x))
1151 p = find_temp_slot_from_address (x);
1153 /* If X is not in memory or is at a constant address, it cannot be in
1154 a temporary slot, but it can contain something whose address was
1156 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1158 for (p = temp_slots; p; p = p->next)
1159 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1165 /* First see if we can find a match. */
1167 p = find_temp_slot_from_address (XEXP (x, 0));
1171 /* Move everything at our level whose address was taken to our new
1172 level in case we used its address. */
1173 struct temp_slot *q;
1175 if (p->level == temp_slot_level)
1177 for (q = temp_slots; q; q = q->next)
1178 if (q != p && q->addr_taken && q->level == p->level)
1187 /* Otherwise, preserve all non-kept slots at this level. */
1188 for (p = temp_slots; p; p = p->next)
1189 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1193 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1194 with that RTL_EXPR, promote it into a temporary slot at the present
1195 level so it will not be freed when we free slots made in the
1199 preserve_rtl_expr_result (x)
1202 struct temp_slot *p;
1204 /* If X is not in memory or is at a constant address, it cannot be in
1205 a temporary slot. */
1206 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1209 /* If we can find a match, move it to our level unless it is already at
1211 p = find_temp_slot_from_address (XEXP (x, 0));
1214 p->level = MIN (p->level, temp_slot_level);
1221 /* Free all temporaries used so far. This is normally called at the end
1222 of generating code for a statement. Don't free any temporaries
1223 currently in use for an RTL_EXPR that hasn't yet been emitted.
1224 We could eventually do better than this since it can be reused while
1225 generating the same RTL_EXPR, but this is complex and probably not
1231 struct temp_slot *p;
1233 for (p = temp_slots; p; p = p->next)
1234 if (p->in_use && p->level == temp_slot_level && ! p->keep
1235 && p->rtl_expr == 0)
1238 combine_temp_slots ();
1241 /* Free all temporary slots used in T, an RTL_EXPR node. */
1244 free_temps_for_rtl_expr (t)
1247 struct temp_slot *p;
1249 for (p = temp_slots; p; p = p->next)
1250 if (p->rtl_expr == t)
1252 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1253 needs to be preserved. This can happen if a temporary in
1254 the RTL_EXPR was addressed; preserve_temp_slots will move
1255 the temporary into a higher level. */
1256 if (temp_slot_level <= p->level)
1259 p->rtl_expr = NULL_TREE;
1262 combine_temp_slots ();
1265 /* Mark all temporaries ever allocated in this function as not suitable
1266 for reuse until the current level is exited. */
1269 mark_all_temps_used ()
1271 struct temp_slot *p;
1273 for (p = temp_slots; p; p = p->next)
1275 p->in_use = p->keep = 1;
1276 p->level = MIN (p->level, temp_slot_level);
1280 /* Push deeper into the nesting level for stack temporaries. */
1288 /* Likewise, but save the new level as the place to allocate variables
1293 push_temp_slots_for_block ()
1297 var_temp_slot_level = temp_slot_level;
1300 /* Likewise, but save the new level as the place to allocate temporaries
1301 for TARGET_EXPRs. */
1304 push_temp_slots_for_target ()
1308 target_temp_slot_level = temp_slot_level;
1311 /* Set and get the value of target_temp_slot_level. The only
1312 permitted use of these functions is to save and restore this value. */
1315 get_target_temp_slot_level ()
1317 return target_temp_slot_level;
1321 set_target_temp_slot_level (level)
1324 target_temp_slot_level = level;
1328 /* Pop a temporary nesting level. All slots in use in the current level
1334 struct temp_slot *p;
1336 for (p = temp_slots; p; p = p->next)
1337 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1340 combine_temp_slots ();
1345 /* Initialize temporary slots. */
1350 /* We have not allocated any temporaries yet. */
1352 temp_slot_level = 0;
1353 var_temp_slot_level = 0;
1354 target_temp_slot_level = 0;
1357 /* Retroactively move an auto variable from a register to a stack slot.
1358 This is done when an address-reference to the variable is seen. */
1361 put_var_into_stack (decl)
1365 enum machine_mode promoted_mode, decl_mode;
1366 struct function *function = 0;
1368 int can_use_addressof;
1369 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1370 int usedp = (TREE_USED (decl)
1371 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1373 context = decl_function_context (decl);
1375 /* Get the current rtl used for this object and its original mode. */
1376 reg = (TREE_CODE (decl) == SAVE_EXPR
1377 ? SAVE_EXPR_RTL (decl)
1378 : DECL_RTL_IF_SET (decl));
1380 /* No need to do anything if decl has no rtx yet
1381 since in that case caller is setting TREE_ADDRESSABLE
1382 and a stack slot will be assigned when the rtl is made. */
1386 /* Get the declared mode for this object. */
1387 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1388 : DECL_MODE (decl));
1389 /* Get the mode it's actually stored in. */
1390 promoted_mode = GET_MODE (reg);
1392 /* If this variable comes from an outer function, find that
1393 function's saved context. Don't use find_function_data here,
1394 because it might not be in any active function.
1395 FIXME: Is that really supposed to happen?
1396 It does in ObjC at least. */
1397 if (context != current_function_decl && context != inline_function_decl)
1398 for (function = outer_function_chain; function; function = function->outer)
1399 if (function->decl == context)
1402 /* If this is a variable-size object with a pseudo to address it,
1403 put that pseudo into the stack, if the var is nonlocal. */
1404 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1405 && GET_CODE (reg) == MEM
1406 && GET_CODE (XEXP (reg, 0)) == REG
1407 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1409 reg = XEXP (reg, 0);
1410 decl_mode = promoted_mode = GET_MODE (reg);
1416 /* FIXME make it work for promoted modes too */
1417 && decl_mode == promoted_mode
1418 #ifdef NON_SAVING_SETJMP
1419 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1423 /* If we can't use ADDRESSOF, make sure we see through one we already
1425 if (! can_use_addressof && GET_CODE (reg) == MEM
1426 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1427 reg = XEXP (XEXP (reg, 0), 0);
1429 /* Now we should have a value that resides in one or more pseudo regs. */
1431 if (GET_CODE (reg) == REG)
1433 /* If this variable lives in the current function and we don't need
1434 to put things in the stack for the sake of setjmp, try to keep it
1435 in a register until we know we actually need the address. */
1436 if (can_use_addressof)
1437 gen_mem_addressof (reg, decl);
1439 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1440 decl_mode, volatilep, 0, usedp, 0);
1442 else if (GET_CODE (reg) == CONCAT)
1444 /* A CONCAT contains two pseudos; put them both in the stack.
1445 We do it so they end up consecutive.
1446 We fixup references to the parts only after we fixup references
1447 to the whole CONCAT, lest we do double fixups for the latter
1449 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1450 tree part_type = type_for_mode (part_mode, 0);
1451 rtx lopart = XEXP (reg, 0);
1452 rtx hipart = XEXP (reg, 1);
1453 #ifdef FRAME_GROWS_DOWNWARD
1454 /* Since part 0 should have a lower address, do it second. */
1455 put_reg_into_stack (function, hipart, part_type, part_mode,
1456 part_mode, volatilep, 0, 0, 0);
1457 put_reg_into_stack (function, lopart, part_type, part_mode,
1458 part_mode, volatilep, 0, 0, 0);
1460 put_reg_into_stack (function, lopart, part_type, part_mode,
1461 part_mode, volatilep, 0, 0, 0);
1462 put_reg_into_stack (function, hipart, part_type, part_mode,
1463 part_mode, volatilep, 0, 0, 0);
1466 /* Change the CONCAT into a combined MEM for both parts. */
1467 PUT_CODE (reg, MEM);
1468 MEM_ATTRS (reg) = 0;
1470 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1471 already computed alias sets. Here we want to re-generate. */
1473 SET_DECL_RTL (decl, NULL);
1474 set_mem_attributes (reg, decl, 1);
1476 SET_DECL_RTL (decl, reg);
1478 /* The two parts are in memory order already.
1479 Use the lower parts address as ours. */
1480 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1481 /* Prevent sharing of rtl that might lose. */
1482 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1483 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1486 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1488 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1489 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1496 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1497 into the stack frame of FUNCTION (0 means the current function).
1498 DECL_MODE is the machine mode of the user-level data type.
1499 PROMOTED_MODE is the machine mode of the register.
1500 VOLATILE_P is nonzero if this is for a "volatile" decl.
1501 USED_P is nonzero if this reg might have already been used in an insn. */
1504 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1505 original_regno, used_p, ht)
1506 struct function *function;
1509 enum machine_mode promoted_mode, decl_mode;
1511 unsigned int original_regno;
1513 struct hash_table *ht;
1515 struct function *func = function ? function : cfun;
1517 unsigned int regno = original_regno;
1520 regno = REGNO (reg);
1522 if (regno < func->x_max_parm_reg)
1523 new = func->x_parm_reg_stack_loc[regno];
1526 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1528 PUT_CODE (reg, MEM);
1529 PUT_MODE (reg, decl_mode);
1530 XEXP (reg, 0) = XEXP (new, 0);
1531 MEM_ATTRS (reg) = 0;
1532 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1533 MEM_VOLATILE_P (reg) = volatile_p;
1535 /* If this is a memory ref that contains aggregate components,
1536 mark it as such for cse and loop optimize. If we are reusing a
1537 previously generated stack slot, then we need to copy the bit in
1538 case it was set for other reasons. For instance, it is set for
1539 __builtin_va_alist. */
1542 MEM_SET_IN_STRUCT_P (reg,
1543 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1544 set_mem_alias_set (reg, get_alias_set (type));
1548 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1551 /* Make sure that all refs to the variable, previously made
1552 when it was a register, are fixed up to be valid again.
1553 See function above for meaning of arguments. */
1556 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1557 struct function *function;
1560 enum machine_mode promoted_mode;
1561 struct hash_table *ht;
1563 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1567 struct var_refs_queue *temp;
1570 = (struct var_refs_queue *) ggc_alloc (sizeof (struct var_refs_queue));
1571 temp->modified = reg;
1572 temp->promoted_mode = promoted_mode;
1573 temp->unsignedp = unsigned_p;
1574 temp->next = function->fixup_var_refs_queue;
1575 function->fixup_var_refs_queue = temp;
1578 /* Variable is local; fix it up now. */
1579 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1583 fixup_var_refs (var, promoted_mode, unsignedp, may_share, ht)
1585 enum machine_mode promoted_mode;
1587 struct hash_table *ht;
1591 rtx first_insn = get_insns ();
1592 struct sequence_stack *stack = seq_stack;
1593 tree rtl_exps = rtl_expr_chain;
1595 /* If there's a hash table, it must record all uses of VAR. */
1600 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1605 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1606 stack == 0, may_share);
1608 /* Scan all pending sequences too. */
1609 for (; stack; stack = stack->next)
1611 push_to_full_sequence (stack->first, stack->last);
1612 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1613 stack->next != 0, may_share);
1614 /* Update remembered end of sequence
1615 in case we added an insn at the end. */
1616 stack->last = get_last_insn ();
1620 /* Scan all waiting RTL_EXPRs too. */
1621 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1623 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1624 if (seq != const0_rtx && seq != 0)
1626 push_to_sequence (seq);
1627 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1634 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1635 some part of an insn. Return a struct fixup_replacement whose OLD
1636 value is equal to X. Allocate a new structure if no such entry exists. */
1638 static struct fixup_replacement *
1639 find_fixup_replacement (replacements, x)
1640 struct fixup_replacement **replacements;
1643 struct fixup_replacement *p;
1645 /* See if we have already replaced this. */
1646 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1651 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1654 p->next = *replacements;
1661 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1662 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1663 for the current function. MAY_SHARE is either a MEM that is not
1664 to be unshared or a list of them. */
1667 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel, may_share)
1670 enum machine_mode promoted_mode;
1677 /* fixup_var_refs_insn might modify insn, so save its next
1679 rtx next = NEXT_INSN (insn);
1681 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1682 the three sequences they (potentially) contain, and process
1683 them recursively. The CALL_INSN itself is not interesting. */
1685 if (GET_CODE (insn) == CALL_INSN
1686 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1690 /* Look at the Normal call, sibling call and tail recursion
1691 sequences attached to the CALL_PLACEHOLDER. */
1692 for (i = 0; i < 3; i++)
1694 rtx seq = XEXP (PATTERN (insn), i);
1697 push_to_sequence (seq);
1698 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1700 XEXP (PATTERN (insn), i) = get_insns ();
1706 else if (INSN_P (insn))
1707 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1714 /* Look up the insns which reference VAR in HT and fix them up. Other
1715 arguments are the same as fixup_var_refs_insns.
1717 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1718 because the hash table will point straight to the interesting insn
1719 (inside the CALL_PLACEHOLDER). */
1722 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp, may_share)
1723 struct hash_table *ht;
1725 enum machine_mode promoted_mode;
1729 struct insns_for_mem_entry *ime
1730 = (struct insns_for_mem_entry *) hash_lookup (ht, var,
1731 /*create=*/0, /*copy=*/0);
1734 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1735 if (INSN_P (XEXP (insn_list, 0)))
1736 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1737 unsignedp, 1, may_share);
1741 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1742 the insn under examination, VAR is the variable to fix up
1743 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1744 TOPLEVEL is nonzero if this is the main insn chain for this
1748 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel, no_share)
1751 enum machine_mode promoted_mode;
1757 rtx set, prev, prev_set;
1760 /* Remember the notes in case we delete the insn. */
1761 note = REG_NOTES (insn);
1763 /* If this is a CLOBBER of VAR, delete it.
1765 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1766 and REG_RETVAL notes too. */
1767 if (GET_CODE (PATTERN (insn)) == CLOBBER
1768 && (XEXP (PATTERN (insn), 0) == var
1769 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1770 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1771 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1773 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1774 /* The REG_LIBCALL note will go away since we are going to
1775 turn INSN into a NOTE, so just delete the
1776 corresponding REG_RETVAL note. */
1777 remove_note (XEXP (note, 0),
1778 find_reg_note (XEXP (note, 0), REG_RETVAL,
1784 /* The insn to load VAR from a home in the arglist
1785 is now a no-op. When we see it, just delete it.
1786 Similarly if this is storing VAR from a register from which
1787 it was loaded in the previous insn. This will occur
1788 when an ADDRESSOF was made for an arglist slot. */
1790 && (set = single_set (insn)) != 0
1791 && SET_DEST (set) == var
1792 /* If this represents the result of an insn group,
1793 don't delete the insn. */
1794 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1795 && (rtx_equal_p (SET_SRC (set), var)
1796 || (GET_CODE (SET_SRC (set)) == REG
1797 && (prev = prev_nonnote_insn (insn)) != 0
1798 && (prev_set = single_set (prev)) != 0
1799 && SET_DEST (prev_set) == SET_SRC (set)
1800 && rtx_equal_p (SET_SRC (prev_set), var))))
1806 struct fixup_replacement *replacements = 0;
1807 rtx next_insn = NEXT_INSN (insn);
1809 if (SMALL_REGISTER_CLASSES)
1811 /* If the insn that copies the results of a CALL_INSN
1812 into a pseudo now references VAR, we have to use an
1813 intermediate pseudo since we want the life of the
1814 return value register to be only a single insn.
1816 If we don't use an intermediate pseudo, such things as
1817 address computations to make the address of VAR valid
1818 if it is not can be placed between the CALL_INSN and INSN.
1820 To make sure this doesn't happen, we record the destination
1821 of the CALL_INSN and see if the next insn uses both that
1824 if (call_dest != 0 && GET_CODE (insn) == INSN
1825 && reg_mentioned_p (var, PATTERN (insn))
1826 && reg_mentioned_p (call_dest, PATTERN (insn)))
1828 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1830 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1832 PATTERN (insn) = replace_rtx (PATTERN (insn),
1836 if (GET_CODE (insn) == CALL_INSN
1837 && GET_CODE (PATTERN (insn)) == SET)
1838 call_dest = SET_DEST (PATTERN (insn));
1839 else if (GET_CODE (insn) == CALL_INSN
1840 && GET_CODE (PATTERN (insn)) == PARALLEL
1841 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1842 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1847 /* See if we have to do anything to INSN now that VAR is in
1848 memory. If it needs to be loaded into a pseudo, use a single
1849 pseudo for the entire insn in case there is a MATCH_DUP
1850 between two operands. We pass a pointer to the head of
1851 a list of struct fixup_replacements. If fixup_var_refs_1
1852 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1853 it will record them in this list.
1855 If it allocated a pseudo for any replacement, we copy into
1858 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1859 &replacements, no_share);
1861 /* If this is last_parm_insn, and any instructions were output
1862 after it to fix it up, then we must set last_parm_insn to
1863 the last such instruction emitted. */
1864 if (insn == last_parm_insn)
1865 last_parm_insn = PREV_INSN (next_insn);
1867 while (replacements)
1869 struct fixup_replacement *next;
1871 if (GET_CODE (replacements->new) == REG)
1876 /* OLD might be a (subreg (mem)). */
1877 if (GET_CODE (replacements->old) == SUBREG)
1879 = fixup_memory_subreg (replacements->old, insn,
1883 = fixup_stack_1 (replacements->old, insn);
1885 insert_before = insn;
1887 /* If we are changing the mode, do a conversion.
1888 This might be wasteful, but combine.c will
1889 eliminate much of the waste. */
1891 if (GET_MODE (replacements->new)
1892 != GET_MODE (replacements->old))
1895 convert_move (replacements->new,
1896 replacements->old, unsignedp);
1897 seq = gen_sequence ();
1901 seq = gen_move_insn (replacements->new,
1904 emit_insn_before (seq, insert_before);
1907 next = replacements->next;
1908 free (replacements);
1909 replacements = next;
1913 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1914 But don't touch other insns referred to by reg-notes;
1915 we will get them elsewhere. */
1918 if (GET_CODE (note) != INSN_LIST)
1920 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1922 note = XEXP (note, 1);
1926 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1927 See if the rtx expression at *LOC in INSN needs to be changed.
1929 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1930 contain a list of original rtx's and replacements. If we find that we need
1931 to modify this insn by replacing a memory reference with a pseudo or by
1932 making a new MEM to implement a SUBREG, we consult that list to see if
1933 we have already chosen a replacement. If none has already been allocated,
1934 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1935 or the SUBREG, as appropriate, to the pseudo. */
1938 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements, no_share)
1940 enum machine_mode promoted_mode;
1943 struct fixup_replacement **replacements;
1948 RTX_CODE code = GET_CODE (x);
1951 struct fixup_replacement *replacement;
1956 if (XEXP (x, 0) == var)
1958 /* Prevent sharing of rtl that might lose. */
1959 rtx sub = copy_rtx (XEXP (var, 0));
1961 if (! validate_change (insn, loc, sub, 0))
1963 rtx y = gen_reg_rtx (GET_MODE (sub));
1966 /* We should be able to replace with a register or all is lost.
1967 Note that we can't use validate_change to verify this, since
1968 we're not caring for replacing all dups simultaneously. */
1969 if (! validate_replace_rtx (*loc, y, insn))
1972 /* Careful! First try to recognize a direct move of the
1973 value, mimicking how things are done in gen_reload wrt
1974 PLUS. Consider what happens when insn is a conditional
1975 move instruction and addsi3 clobbers flags. */
1978 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1979 seq = gen_sequence ();
1982 if (recog_memoized (new_insn) < 0)
1984 /* That failed. Fall back on force_operand and hope. */
1987 sub = force_operand (sub, y);
1989 emit_insn (gen_move_insn (y, sub));
1990 seq = gen_sequence ();
1995 /* Don't separate setter from user. */
1996 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1997 insn = PREV_INSN (insn);
2000 emit_insn_before (seq, insn);
2008 /* If we already have a replacement, use it. Otherwise,
2009 try to fix up this address in case it is invalid. */
2011 replacement = find_fixup_replacement (replacements, var);
2012 if (replacement->new)
2014 *loc = replacement->new;
2018 *loc = replacement->new = x = fixup_stack_1 (x, insn);
2020 /* Unless we are forcing memory to register or we changed the mode,
2021 we can leave things the way they are if the insn is valid. */
2023 INSN_CODE (insn) = -1;
2024 if (! flag_force_mem && GET_MODE (x) == promoted_mode
2025 && recog_memoized (insn) >= 0)
2028 *loc = replacement->new = gen_reg_rtx (promoted_mode);
2032 /* If X contains VAR, we need to unshare it here so that we update
2033 each occurrence separately. But all identical MEMs in one insn
2034 must be replaced with the same rtx because of the possibility of
2037 if (reg_mentioned_p (var, x))
2039 replacement = find_fixup_replacement (replacements, x);
2040 if (replacement->new == 0)
2041 replacement->new = copy_most_rtx (x, no_share);
2043 *loc = x = replacement->new;
2044 code = GET_CODE (x);
2061 /* Note that in some cases those types of expressions are altered
2062 by optimize_bit_field, and do not survive to get here. */
2063 if (XEXP (x, 0) == var
2064 || (GET_CODE (XEXP (x, 0)) == SUBREG
2065 && SUBREG_REG (XEXP (x, 0)) == var))
2067 /* Get TEM as a valid MEM in the mode presently in the insn.
2069 We don't worry about the possibility of MATCH_DUP here; it
2070 is highly unlikely and would be tricky to handle. */
2073 if (GET_CODE (tem) == SUBREG)
2075 if (GET_MODE_BITSIZE (GET_MODE (tem))
2076 > GET_MODE_BITSIZE (GET_MODE (var)))
2078 replacement = find_fixup_replacement (replacements, var);
2079 if (replacement->new == 0)
2080 replacement->new = gen_reg_rtx (GET_MODE (var));
2081 SUBREG_REG (tem) = replacement->new;
2083 /* The following code works only if we have a MEM, so we
2084 need to handle the subreg here. We directly substitute
2085 it assuming that a subreg must be OK here. We already
2086 scheduled a replacement to copy the mem into the
2092 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2095 tem = fixup_stack_1 (tem, insn);
2097 /* Unless we want to load from memory, get TEM into the proper mode
2098 for an extract from memory. This can only be done if the
2099 extract is at a constant position and length. */
2101 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2102 && GET_CODE (XEXP (x, 2)) == CONST_INT
2103 && ! mode_dependent_address_p (XEXP (tem, 0))
2104 && ! MEM_VOLATILE_P (tem))
2106 enum machine_mode wanted_mode = VOIDmode;
2107 enum machine_mode is_mode = GET_MODE (tem);
2108 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2110 if (GET_CODE (x) == ZERO_EXTRACT)
2112 enum machine_mode new_mode
2113 = mode_for_extraction (EP_extzv, 1);
2114 if (new_mode != MAX_MACHINE_MODE)
2115 wanted_mode = new_mode;
2117 else if (GET_CODE (x) == SIGN_EXTRACT)
2119 enum machine_mode new_mode
2120 = mode_for_extraction (EP_extv, 1);
2121 if (new_mode != MAX_MACHINE_MODE)
2122 wanted_mode = new_mode;
2125 /* If we have a narrower mode, we can do something. */
2126 if (wanted_mode != VOIDmode
2127 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2129 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2130 rtx old_pos = XEXP (x, 2);
2133 /* If the bytes and bits are counted differently, we
2134 must adjust the offset. */
2135 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2136 offset = (GET_MODE_SIZE (is_mode)
2137 - GET_MODE_SIZE (wanted_mode) - offset);
2139 pos %= GET_MODE_BITSIZE (wanted_mode);
2141 newmem = adjust_address_nv (tem, wanted_mode, offset);
2143 /* Make the change and see if the insn remains valid. */
2144 INSN_CODE (insn) = -1;
2145 XEXP (x, 0) = newmem;
2146 XEXP (x, 2) = GEN_INT (pos);
2148 if (recog_memoized (insn) >= 0)
2151 /* Otherwise, restore old position. XEXP (x, 0) will be
2153 XEXP (x, 2) = old_pos;
2157 /* If we get here, the bitfield extract insn can't accept a memory
2158 reference. Copy the input into a register. */
2160 tem1 = gen_reg_rtx (GET_MODE (tem));
2161 emit_insn_before (gen_move_insn (tem1, tem), insn);
2168 if (SUBREG_REG (x) == var)
2170 /* If this is a special SUBREG made because VAR was promoted
2171 from a wider mode, replace it with VAR and call ourself
2172 recursively, this time saying that the object previously
2173 had its current mode (by virtue of the SUBREG). */
2175 if (SUBREG_PROMOTED_VAR_P (x))
2178 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2183 /* If this SUBREG makes VAR wider, it has become a paradoxical
2184 SUBREG with VAR in memory, but these aren't allowed at this
2185 stage of the compilation. So load VAR into a pseudo and take
2186 a SUBREG of that pseudo. */
2187 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2189 replacement = find_fixup_replacement (replacements, var);
2190 if (replacement->new == 0)
2191 replacement->new = gen_reg_rtx (promoted_mode);
2192 SUBREG_REG (x) = replacement->new;
2196 /* See if we have already found a replacement for this SUBREG.
2197 If so, use it. Otherwise, make a MEM and see if the insn
2198 is recognized. If not, or if we should force MEM into a register,
2199 make a pseudo for this SUBREG. */
2200 replacement = find_fixup_replacement (replacements, x);
2201 if (replacement->new)
2203 *loc = replacement->new;
2207 replacement->new = *loc = fixup_memory_subreg (x, insn,
2210 INSN_CODE (insn) = -1;
2211 if (! flag_force_mem && recog_memoized (insn) >= 0)
2214 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2220 /* First do special simplification of bit-field references. */
2221 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2222 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2223 optimize_bit_field (x, insn, 0);
2224 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2225 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2226 optimize_bit_field (x, insn, 0);
2228 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2229 into a register and then store it back out. */
2230 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2231 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2232 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2233 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2234 > GET_MODE_SIZE (GET_MODE (var))))
2236 replacement = find_fixup_replacement (replacements, var);
2237 if (replacement->new == 0)
2238 replacement->new = gen_reg_rtx (GET_MODE (var));
2240 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2241 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2244 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2245 insn into a pseudo and store the low part of the pseudo into VAR. */
2246 if (GET_CODE (SET_DEST (x)) == SUBREG
2247 && SUBREG_REG (SET_DEST (x)) == var
2248 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2249 > GET_MODE_SIZE (GET_MODE (var))))
2251 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2252 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2259 rtx dest = SET_DEST (x);
2260 rtx src = SET_SRC (x);
2261 rtx outerdest = dest;
2263 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2264 || GET_CODE (dest) == SIGN_EXTRACT
2265 || GET_CODE (dest) == ZERO_EXTRACT)
2266 dest = XEXP (dest, 0);
2268 if (GET_CODE (src) == SUBREG)
2269 src = SUBREG_REG (src);
2271 /* If VAR does not appear at the top level of the SET
2272 just scan the lower levels of the tree. */
2274 if (src != var && dest != var)
2277 /* We will need to rerecognize this insn. */
2278 INSN_CODE (insn) = -1;
2280 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2281 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2283 /* Since this case will return, ensure we fixup all the
2285 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2286 insn, replacements, no_share);
2287 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2288 insn, replacements, no_share);
2289 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2290 insn, replacements, no_share);
2292 tem = XEXP (outerdest, 0);
2294 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2295 that may appear inside a ZERO_EXTRACT.
2296 This was legitimate when the MEM was a REG. */
2297 if (GET_CODE (tem) == SUBREG
2298 && SUBREG_REG (tem) == var)
2299 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2301 tem = fixup_stack_1 (tem, insn);
2303 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2304 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2305 && ! mode_dependent_address_p (XEXP (tem, 0))
2306 && ! MEM_VOLATILE_P (tem))
2308 enum machine_mode wanted_mode;
2309 enum machine_mode is_mode = GET_MODE (tem);
2310 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2312 wanted_mode = mode_for_extraction (EP_insv, 0);
2314 /* If we have a narrower mode, we can do something. */
2315 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2317 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2318 rtx old_pos = XEXP (outerdest, 2);
2321 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2322 offset = (GET_MODE_SIZE (is_mode)
2323 - GET_MODE_SIZE (wanted_mode) - offset);
2325 pos %= GET_MODE_BITSIZE (wanted_mode);
2327 newmem = adjust_address_nv (tem, wanted_mode, offset);
2329 /* Make the change and see if the insn remains valid. */
2330 INSN_CODE (insn) = -1;
2331 XEXP (outerdest, 0) = newmem;
2332 XEXP (outerdest, 2) = GEN_INT (pos);
2334 if (recog_memoized (insn) >= 0)
2337 /* Otherwise, restore old position. XEXP (x, 0) will be
2339 XEXP (outerdest, 2) = old_pos;
2343 /* If we get here, the bit-field store doesn't allow memory
2344 or isn't located at a constant position. Load the value into
2345 a register, do the store, and put it back into memory. */
2347 tem1 = gen_reg_rtx (GET_MODE (tem));
2348 emit_insn_before (gen_move_insn (tem1, tem), insn);
2349 emit_insn_after (gen_move_insn (tem, tem1), insn);
2350 XEXP (outerdest, 0) = tem1;
2354 /* STRICT_LOW_PART is a no-op on memory references
2355 and it can cause combinations to be unrecognizable,
2358 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2359 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2361 /* A valid insn to copy VAR into or out of a register
2362 must be left alone, to avoid an infinite loop here.
2363 If the reference to VAR is by a subreg, fix that up,
2364 since SUBREG is not valid for a memref.
2365 Also fix up the address of the stack slot.
2367 Note that we must not try to recognize the insn until
2368 after we know that we have valid addresses and no
2369 (subreg (mem ...) ...) constructs, since these interfere
2370 with determining the validity of the insn. */
2372 if ((SET_SRC (x) == var
2373 || (GET_CODE (SET_SRC (x)) == SUBREG
2374 && SUBREG_REG (SET_SRC (x)) == var))
2375 && (GET_CODE (SET_DEST (x)) == REG
2376 || (GET_CODE (SET_DEST (x)) == SUBREG
2377 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2378 && GET_MODE (var) == promoted_mode
2379 && x == single_set (insn))
2383 if (GET_CODE (SET_SRC (x)) == SUBREG
2384 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2385 > GET_MODE_SIZE (GET_MODE (var))))
2387 /* This (subreg VAR) is now a paradoxical subreg. We need
2388 to replace VAR instead of the subreg. */
2389 replacement = find_fixup_replacement (replacements, var);
2390 if (replacement->new == NULL_RTX)
2391 replacement->new = gen_reg_rtx (GET_MODE (var));
2392 SUBREG_REG (SET_SRC (x)) = replacement->new;
2396 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2397 if (replacement->new)
2398 SET_SRC (x) = replacement->new;
2399 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2400 SET_SRC (x) = replacement->new
2401 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2404 SET_SRC (x) = replacement->new
2405 = fixup_stack_1 (SET_SRC (x), insn);
2408 if (recog_memoized (insn) >= 0)
2411 /* INSN is not valid, but we know that we want to
2412 copy SET_SRC (x) to SET_DEST (x) in some way. So
2413 we generate the move and see whether it requires more
2414 than one insn. If it does, we emit those insns and
2415 delete INSN. Otherwise, we an just replace the pattern
2416 of INSN; we have already verified above that INSN has
2417 no other function that to do X. */
2419 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2420 if (GET_CODE (pat) == SEQUENCE)
2422 last = emit_insn_before (pat, insn);
2424 /* INSN might have REG_RETVAL or other important notes, so
2425 we need to store the pattern of the last insn in the
2426 sequence into INSN similarly to the normal case. LAST
2427 should not have REG_NOTES, but we allow them if INSN has
2429 if (REG_NOTES (last) && REG_NOTES (insn))
2431 if (REG_NOTES (last))
2432 REG_NOTES (insn) = REG_NOTES (last);
2433 PATTERN (insn) = PATTERN (last);
2438 PATTERN (insn) = pat;
2443 if ((SET_DEST (x) == var
2444 || (GET_CODE (SET_DEST (x)) == SUBREG
2445 && SUBREG_REG (SET_DEST (x)) == var))
2446 && (GET_CODE (SET_SRC (x)) == REG
2447 || (GET_CODE (SET_SRC (x)) == SUBREG
2448 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2449 && GET_MODE (var) == promoted_mode
2450 && x == single_set (insn))
2454 if (GET_CODE (SET_DEST (x)) == SUBREG)
2455 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2458 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2460 if (recog_memoized (insn) >= 0)
2463 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2464 if (GET_CODE (pat) == SEQUENCE)
2466 last = emit_insn_before (pat, insn);
2468 /* INSN might have REG_RETVAL or other important notes, so
2469 we need to store the pattern of the last insn in the
2470 sequence into INSN similarly to the normal case. LAST
2471 should not have REG_NOTES, but we allow them if INSN has
2473 if (REG_NOTES (last) && REG_NOTES (insn))
2475 if (REG_NOTES (last))
2476 REG_NOTES (insn) = REG_NOTES (last);
2477 PATTERN (insn) = PATTERN (last);
2482 PATTERN (insn) = pat;
2487 /* Otherwise, storing into VAR must be handled specially
2488 by storing into a temporary and copying that into VAR
2489 with a new insn after this one. Note that this case
2490 will be used when storing into a promoted scalar since
2491 the insn will now have different modes on the input
2492 and output and hence will be invalid (except for the case
2493 of setting it to a constant, which does not need any
2494 change if it is valid). We generate extra code in that case,
2495 but combine.c will eliminate it. */
2500 rtx fixeddest = SET_DEST (x);
2501 enum machine_mode temp_mode;
2503 /* STRICT_LOW_PART can be discarded, around a MEM. */
2504 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2505 fixeddest = XEXP (fixeddest, 0);
2506 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2507 if (GET_CODE (fixeddest) == SUBREG)
2509 fixeddest = fixup_memory_subreg (fixeddest, insn,
2511 temp_mode = GET_MODE (fixeddest);
2515 fixeddest = fixup_stack_1 (fixeddest, insn);
2516 temp_mode = promoted_mode;
2519 temp = gen_reg_rtx (temp_mode);
2521 emit_insn_after (gen_move_insn (fixeddest,
2522 gen_lowpart (GET_MODE (fixeddest),
2526 SET_DEST (x) = temp;
2534 /* Nothing special about this RTX; fix its operands. */
2536 fmt = GET_RTX_FORMAT (code);
2537 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2540 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2542 else if (fmt[i] == 'E')
2545 for (j = 0; j < XVECLEN (x, i); j++)
2546 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2547 insn, replacements, no_share);
2552 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2553 The REG was placed on the stack, so X now has the form (SUBREG:m1
2556 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2557 must be emitted to compute NEWADDR, put them before INSN.
2559 UNCRITICAL nonzero means accept paradoxical subregs.
2560 This is used for subregs found inside REG_NOTES. */
2563 fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2566 enum machine_mode promoted_mode;
2570 rtx mem = SUBREG_REG (x);
2571 rtx addr = XEXP (mem, 0);
2572 enum machine_mode mode = GET_MODE (x);
2575 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2576 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2579 offset = SUBREG_BYTE (x);
2580 if (BYTES_BIG_ENDIAN)
2581 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2582 the offset so that it points to the right location within the
2584 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2586 if (!flag_force_addr
2587 && memory_address_p (mode, plus_constant (addr, offset)))
2588 /* Shortcut if no insns need be emitted. */
2589 return adjust_address (mem, mode, offset);
2592 result = adjust_address (mem, mode, offset);
2593 emit_insn_before (gen_sequence (), insn);
2598 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2599 Replace subexpressions of X in place.
2600 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2601 Otherwise return X, with its contents possibly altered.
2603 INSN, PROMOTED_MODE and UNCRITICAL are as for
2604 fixup_memory_subreg. */
2607 walk_fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2610 enum machine_mode promoted_mode;
2620 code = GET_CODE (x);
2622 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2623 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2625 /* Nothing special about this RTX; fix its operands. */
2627 fmt = GET_RTX_FORMAT (code);
2628 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2631 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2632 promoted_mode, uncritical);
2633 else if (fmt[i] == 'E')
2636 for (j = 0; j < XVECLEN (x, i); j++)
2638 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2639 promoted_mode, uncritical);
2645 /* For each memory ref within X, if it refers to a stack slot
2646 with an out of range displacement, put the address in a temp register
2647 (emitting new insns before INSN to load these registers)
2648 and alter the memory ref to use that register.
2649 Replace each such MEM rtx with a copy, to avoid clobberage. */
2652 fixup_stack_1 (x, insn)
2657 RTX_CODE code = GET_CODE (x);
2662 rtx ad = XEXP (x, 0);
2663 /* If we have address of a stack slot but it's not valid
2664 (displacement is too large), compute the sum in a register. */
2665 if (GET_CODE (ad) == PLUS
2666 && GET_CODE (XEXP (ad, 0)) == REG
2667 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2668 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2669 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2670 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2671 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2673 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2674 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2675 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2676 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2679 if (memory_address_p (GET_MODE (x), ad))
2683 temp = copy_to_reg (ad);
2684 seq = gen_sequence ();
2686 emit_insn_before (seq, insn);
2687 return replace_equiv_address (x, temp);
2692 fmt = GET_RTX_FORMAT (code);
2693 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2696 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2697 else if (fmt[i] == 'E')
2700 for (j = 0; j < XVECLEN (x, i); j++)
2701 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2707 /* Optimization: a bit-field instruction whose field
2708 happens to be a byte or halfword in memory
2709 can be changed to a move instruction.
2711 We call here when INSN is an insn to examine or store into a bit-field.
2712 BODY is the SET-rtx to be altered.
2714 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2715 (Currently this is called only from function.c, and EQUIV_MEM
2719 optimize_bit_field (body, insn, equiv_mem)
2727 enum machine_mode mode;
2729 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2730 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2731 bitfield = SET_DEST (body), destflag = 1;
2733 bitfield = SET_SRC (body), destflag = 0;
2735 /* First check that the field being stored has constant size and position
2736 and is in fact a byte or halfword suitably aligned. */
2738 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2739 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2740 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2742 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2746 /* Now check that the containing word is memory, not a register,
2747 and that it is safe to change the machine mode. */
2749 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2750 memref = XEXP (bitfield, 0);
2751 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2753 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2754 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2755 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2756 memref = SUBREG_REG (XEXP (bitfield, 0));
2757 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2759 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2760 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2763 && ! mode_dependent_address_p (XEXP (memref, 0))
2764 && ! MEM_VOLATILE_P (memref))
2766 /* Now adjust the address, first for any subreg'ing
2767 that we are now getting rid of,
2768 and then for which byte of the word is wanted. */
2770 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2773 /* Adjust OFFSET to count bits from low-address byte. */
2774 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2775 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2776 - offset - INTVAL (XEXP (bitfield, 1)));
2778 /* Adjust OFFSET to count bytes from low-address byte. */
2779 offset /= BITS_PER_UNIT;
2780 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2782 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2783 / UNITS_PER_WORD) * UNITS_PER_WORD;
2784 if (BYTES_BIG_ENDIAN)
2785 offset -= (MIN (UNITS_PER_WORD,
2786 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2787 - MIN (UNITS_PER_WORD,
2788 GET_MODE_SIZE (GET_MODE (memref))));
2792 memref = adjust_address (memref, mode, offset);
2793 insns = get_insns ();
2795 emit_insns_before (insns, insn);
2797 /* Store this memory reference where
2798 we found the bit field reference. */
2802 validate_change (insn, &SET_DEST (body), memref, 1);
2803 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2805 rtx src = SET_SRC (body);
2806 while (GET_CODE (src) == SUBREG
2807 && SUBREG_BYTE (src) == 0)
2808 src = SUBREG_REG (src);
2809 if (GET_MODE (src) != GET_MODE (memref))
2810 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2811 validate_change (insn, &SET_SRC (body), src, 1);
2813 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2814 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2815 /* This shouldn't happen because anything that didn't have
2816 one of these modes should have got converted explicitly
2817 and then referenced through a subreg.
2818 This is so because the original bit-field was
2819 handled by agg_mode and so its tree structure had
2820 the same mode that memref now has. */
2825 rtx dest = SET_DEST (body);
2827 while (GET_CODE (dest) == SUBREG
2828 && SUBREG_BYTE (dest) == 0
2829 && (GET_MODE_CLASS (GET_MODE (dest))
2830 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2831 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2833 dest = SUBREG_REG (dest);
2835 validate_change (insn, &SET_DEST (body), dest, 1);
2837 if (GET_MODE (dest) == GET_MODE (memref))
2838 validate_change (insn, &SET_SRC (body), memref, 1);
2841 /* Convert the mem ref to the destination mode. */
2842 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2845 convert_move (newreg, memref,
2846 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2850 validate_change (insn, &SET_SRC (body), newreg, 1);
2854 /* See if we can convert this extraction or insertion into
2855 a simple move insn. We might not be able to do so if this
2856 was, for example, part of a PARALLEL.
2858 If we succeed, write out any needed conversions. If we fail,
2859 it is hard to guess why we failed, so don't do anything
2860 special; just let the optimization be suppressed. */
2862 if (apply_change_group () && seq)
2863 emit_insns_before (seq, insn);
2868 /* These routines are responsible for converting virtual register references
2869 to the actual hard register references once RTL generation is complete.
2871 The following four variables are used for communication between the
2872 routines. They contain the offsets of the virtual registers from their
2873 respective hard registers. */
2875 static int in_arg_offset;
2876 static int var_offset;
2877 static int dynamic_offset;
2878 static int out_arg_offset;
2879 static int cfa_offset;
2881 /* In most machines, the stack pointer register is equivalent to the bottom
2884 #ifndef STACK_POINTER_OFFSET
2885 #define STACK_POINTER_OFFSET 0
2888 /* If not defined, pick an appropriate default for the offset of dynamically
2889 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2890 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2892 #ifndef STACK_DYNAMIC_OFFSET
2894 /* The bottom of the stack points to the actual arguments. If
2895 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2896 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2897 stack space for register parameters is not pushed by the caller, but
2898 rather part of the fixed stack areas and hence not included in
2899 `current_function_outgoing_args_size'. Nevertheless, we must allow
2900 for it when allocating stack dynamic objects. */
2902 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2903 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2904 ((ACCUMULATE_OUTGOING_ARGS \
2905 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2906 + (STACK_POINTER_OFFSET)) \
2909 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2910 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2911 + (STACK_POINTER_OFFSET))
2915 /* On most machines, the CFA coincides with the first incoming parm. */
2917 #ifndef ARG_POINTER_CFA_OFFSET
2918 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2921 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had its
2922 address taken. DECL is the decl or SAVE_EXPR for the object stored in the
2923 register, for later use if we do need to force REG into the stack. REG is
2924 overwritten by the MEM like in put_reg_into_stack. */
2927 gen_mem_addressof (reg, decl)
2931 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2934 /* Calculate this before we start messing with decl's RTL. */
2935 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2937 /* If the original REG was a user-variable, then so is the REG whose
2938 address is being taken. Likewise for unchanging. */
2939 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2940 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2942 PUT_CODE (reg, MEM);
2943 MEM_ATTRS (reg) = 0;
2948 tree type = TREE_TYPE (decl);
2949 enum machine_mode decl_mode
2950 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2951 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2952 : DECL_RTL_IF_SET (decl));
2954 PUT_MODE (reg, decl_mode);
2956 /* Clear DECL_RTL momentarily so functions below will work
2957 properly, then set it again. */
2958 if (DECL_P (decl) && decl_rtl == reg)
2959 SET_DECL_RTL (decl, 0);
2961 set_mem_attributes (reg, decl, 1);
2962 set_mem_alias_set (reg, set);
2964 if (DECL_P (decl) && decl_rtl == reg)
2965 SET_DECL_RTL (decl, reg);
2967 if (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0))
2968 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2971 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2976 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2979 flush_addressof (decl)
2982 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2983 && DECL_RTL (decl) != 0
2984 && GET_CODE (DECL_RTL (decl)) == MEM
2985 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2986 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2987 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2990 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2993 put_addressof_into_stack (r, ht)
2995 struct hash_table *ht;
2998 int volatile_p, used_p;
3000 rtx reg = XEXP (r, 0);
3002 if (GET_CODE (reg) != REG)
3005 decl = ADDRESSOF_DECL (r);
3008 type = TREE_TYPE (decl);
3009 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
3010 && TREE_THIS_VOLATILE (decl));
3011 used_p = (TREE_USED (decl)
3012 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
3021 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
3022 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
3025 /* List of replacements made below in purge_addressof_1 when creating
3026 bitfield insertions. */
3027 static rtx purge_bitfield_addressof_replacements;
3029 /* List of replacements made below in purge_addressof_1 for patterns
3030 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
3031 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
3032 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
3033 enough in complex cases, e.g. when some field values can be
3034 extracted by usage MEM with narrower mode. */
3035 static rtx purge_addressof_replacements;
3037 /* Helper function for purge_addressof. See if the rtx expression at *LOC
3038 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
3039 the stack. If the function returns FALSE then the replacement could not
3043 purge_addressof_1 (loc, insn, force, store, ht)
3047 struct hash_table *ht;
3055 /* Re-start here to avoid recursion in common cases. */
3062 code = GET_CODE (x);
3064 /* If we don't return in any of the cases below, we will recurse inside
3065 the RTX, which will normally result in any ADDRESSOF being forced into
3069 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3070 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3073 else if (code == ADDRESSOF)
3077 if (GET_CODE (XEXP (x, 0)) != MEM)
3079 put_addressof_into_stack (x, ht);
3083 /* We must create a copy of the rtx because it was created by
3084 overwriting a REG rtx which is always shared. */
3085 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3086 if (validate_change (insn, loc, sub, 0)
3087 || validate_replace_rtx (x, sub, insn))
3091 sub = force_operand (sub, NULL_RTX);
3092 if (! validate_change (insn, loc, sub, 0)
3093 && ! validate_replace_rtx (x, sub, insn))
3096 insns = gen_sequence ();
3098 emit_insn_before (insns, insn);
3102 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3104 rtx sub = XEXP (XEXP (x, 0), 0);
3106 if (GET_CODE (sub) == MEM)
3107 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3108 else if (GET_CODE (sub) == REG
3109 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3111 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3113 int size_x, size_sub;
3117 /* When processing REG_NOTES look at the list of
3118 replacements done on the insn to find the register that X
3122 for (tem = purge_bitfield_addressof_replacements;
3124 tem = XEXP (XEXP (tem, 1), 1))
3125 if (rtx_equal_p (x, XEXP (tem, 0)))
3127 *loc = XEXP (XEXP (tem, 1), 0);
3131 /* See comment for purge_addressof_replacements. */
3132 for (tem = purge_addressof_replacements;
3134 tem = XEXP (XEXP (tem, 1), 1))
3135 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3137 rtx z = XEXP (XEXP (tem, 1), 0);
3139 if (GET_MODE (x) == GET_MODE (z)
3140 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3141 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3144 /* It can happen that the note may speak of things
3145 in a wider (or just different) mode than the
3146 code did. This is especially true of
3149 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3152 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3153 && (GET_MODE_SIZE (GET_MODE (x))
3154 > GET_MODE_SIZE (GET_MODE (z))))
3156 /* This can occur as a result in invalid
3157 pointer casts, e.g. float f; ...
3158 *(long long int *)&f.
3159 ??? We could emit a warning here, but
3160 without a line number that wouldn't be
3162 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3165 z = gen_lowpart (GET_MODE (x), z);
3171 /* Sometimes we may not be able to find the replacement. For
3172 example when the original insn was a MEM in a wider mode,
3173 and the note is part of a sign extension of a narrowed
3174 version of that MEM. Gcc testcase compile/990829-1.c can
3175 generate an example of this situation. Rather than complain
3176 we return false, which will prompt our caller to remove the
3181 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3182 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3184 /* Don't even consider working with paradoxical subregs,
3185 or the moral equivalent seen here. */
3186 if (size_x <= size_sub
3187 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3189 /* Do a bitfield insertion to mirror what would happen
3196 rtx p = PREV_INSN (insn);
3199 val = gen_reg_rtx (GET_MODE (x));
3200 if (! validate_change (insn, loc, val, 0))
3202 /* Discard the current sequence and put the
3203 ADDRESSOF on stack. */
3207 seq = gen_sequence ();
3209 emit_insn_before (seq, insn);
3210 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3214 store_bit_field (sub, size_x, 0, GET_MODE (x),
3215 val, GET_MODE_SIZE (GET_MODE (sub)));
3217 /* Make sure to unshare any shared rtl that store_bit_field
3218 might have created. */
3219 unshare_all_rtl_again (get_insns ());
3221 seq = gen_sequence ();
3223 p = emit_insn_after (seq, insn);
3224 if (NEXT_INSN (insn))
3225 compute_insns_for_mem (NEXT_INSN (insn),
3226 p ? NEXT_INSN (p) : NULL_RTX,
3231 rtx p = PREV_INSN (insn);
3234 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3235 GET_MODE (x), GET_MODE (x),
3236 GET_MODE_SIZE (GET_MODE (sub)));
3238 if (! validate_change (insn, loc, val, 0))
3240 /* Discard the current sequence and put the
3241 ADDRESSOF on stack. */
3246 seq = gen_sequence ();
3248 emit_insn_before (seq, insn);
3249 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3253 /* Remember the replacement so that the same one can be done
3254 on the REG_NOTES. */
3255 purge_bitfield_addressof_replacements
3256 = gen_rtx_EXPR_LIST (VOIDmode, x,
3259 purge_bitfield_addressof_replacements));
3261 /* We replaced with a reg -- all done. */
3266 else if (validate_change (insn, loc, sub, 0))
3268 /* Remember the replacement so that the same one can be done
3269 on the REG_NOTES. */
3270 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3274 for (tem = purge_addressof_replacements;
3276 tem = XEXP (XEXP (tem, 1), 1))
3277 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3279 XEXP (XEXP (tem, 1), 0) = sub;
3282 purge_addressof_replacements
3283 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3284 gen_rtx_EXPR_LIST (VOIDmode, sub,
3285 purge_addressof_replacements));
3293 /* Scan all subexpressions. */
3294 fmt = GET_RTX_FORMAT (code);
3295 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3298 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3299 else if (*fmt == 'E')
3300 for (j = 0; j < XVECLEN (x, i); j++)
3301 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3307 /* Return a new hash table entry in HT. */
3309 static struct hash_entry *
3310 insns_for_mem_newfunc (he, ht, k)
3311 struct hash_entry *he;
3312 struct hash_table *ht;
3313 hash_table_key k ATTRIBUTE_UNUSED;
3315 struct insns_for_mem_entry *ifmhe;
3319 ifmhe = ((struct insns_for_mem_entry *)
3320 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3321 ifmhe->insns = NULL_RTX;
3326 /* Return a hash value for K, a REG. */
3328 static unsigned long
3329 insns_for_mem_hash (k)
3332 /* K is really a RTX. Just use the address as the hash value. */
3333 return (unsigned long) k;
3336 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3339 insns_for_mem_comp (k1, k2)
3346 struct insns_for_mem_walk_info
3348 /* The hash table that we are using to record which INSNs use which
3350 struct hash_table *ht;
3352 /* The INSN we are currently processing. */
3355 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3356 to find the insns that use the REGs in the ADDRESSOFs. */
3360 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3361 that might be used in an ADDRESSOF expression, record this INSN in
3362 the hash table given by DATA (which is really a pointer to an
3363 insns_for_mem_walk_info structure). */
3366 insns_for_mem_walk (r, data)
3370 struct insns_for_mem_walk_info *ifmwi
3371 = (struct insns_for_mem_walk_info *) data;
3373 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3374 && GET_CODE (XEXP (*r, 0)) == REG)
3375 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3376 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3378 /* Lookup this MEM in the hashtable, creating it if necessary. */
3379 struct insns_for_mem_entry *ifme
3380 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3385 /* If we have not already recorded this INSN, do so now. Since
3386 we process the INSNs in order, we know that if we have
3387 recorded it it must be at the front of the list. */
3388 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3389 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3396 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3397 which REGs in HT. */
3400 compute_insns_for_mem (insns, last_insn, ht)
3403 struct hash_table *ht;
3406 struct insns_for_mem_walk_info ifmwi;
3409 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3410 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3414 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3418 /* Helper function for purge_addressof called through for_each_rtx.
3419 Returns true iff the rtl is an ADDRESSOF. */
3422 is_addressof (rtl, data)
3424 void *data ATTRIBUTE_UNUSED;
3426 return GET_CODE (*rtl) == ADDRESSOF;
3429 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3430 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3434 purge_addressof (insns)
3438 struct hash_table ht;
3440 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3441 requires a fixup pass over the instruction stream to correct
3442 INSNs that depended on the REG being a REG, and not a MEM. But,
3443 these fixup passes are slow. Furthermore, most MEMs are not
3444 mentioned in very many instructions. So, we speed up the process
3445 by pre-calculating which REGs occur in which INSNs; that allows
3446 us to perform the fixup passes much more quickly. */
3447 hash_table_init (&ht,
3448 insns_for_mem_newfunc,
3450 insns_for_mem_comp);
3451 compute_insns_for_mem (insns, NULL_RTX, &ht);
3453 for (insn = insns; insn; insn = NEXT_INSN (insn))
3454 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3455 || GET_CODE (insn) == CALL_INSN)
3457 if (! purge_addressof_1 (&PATTERN (insn), insn,
3458 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3459 /* If we could not replace the ADDRESSOFs in the insn,
3460 something is wrong. */
3463 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3465 /* If we could not replace the ADDRESSOFs in the insn's notes,
3466 we can just remove the offending notes instead. */
3469 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3471 /* If we find a REG_RETVAL note then the insn is a libcall.
3472 Such insns must have REG_EQUAL notes as well, in order
3473 for later passes of the compiler to work. So it is not
3474 safe to delete the notes here, and instead we abort. */
3475 if (REG_NOTE_KIND (note) == REG_RETVAL)
3477 if (for_each_rtx (¬e, is_addressof, NULL))
3478 remove_note (insn, note);
3484 hash_table_free (&ht);
3485 purge_bitfield_addressof_replacements = 0;
3486 purge_addressof_replacements = 0;
3488 /* REGs are shared. purge_addressof will destructively replace a REG
3489 with a MEM, which creates shared MEMs.
3491 Unfortunately, the children of put_reg_into_stack assume that MEMs
3492 referring to the same stack slot are shared (fixup_var_refs and
3493 the associated hash table code).
3495 So, we have to do another unsharing pass after we have flushed any
3496 REGs that had their address taken into the stack.
3498 It may be worth tracking whether or not we converted any REGs into
3499 MEMs to avoid this overhead when it is not needed. */
3500 unshare_all_rtl_again (get_insns ());
3503 /* Convert a SET of a hard subreg to a set of the appropriate hard
3504 register. A subroutine of purge_hard_subreg_sets. */
3507 purge_single_hard_subreg_set (pattern)
3510 rtx reg = SET_DEST (pattern);
3511 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3514 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3515 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3517 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3518 GET_MODE (SUBREG_REG (reg)),
3521 reg = SUBREG_REG (reg);
3525 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3527 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3528 SET_DEST (pattern) = reg;
3532 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3533 only such SETs that we expect to see are those left in because
3534 integrate can't handle sets of parts of a return value register.
3536 We don't use alter_subreg because we only want to eliminate subregs
3537 of hard registers. */
3540 purge_hard_subreg_sets (insn)
3543 for (; insn; insn = NEXT_INSN (insn))
3547 rtx pattern = PATTERN (insn);
3548 switch (GET_CODE (pattern))
3551 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3552 purge_single_hard_subreg_set (pattern);
3557 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3559 rtx inner_pattern = XVECEXP (pattern, 0, j);
3560 if (GET_CODE (inner_pattern) == SET
3561 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3562 purge_single_hard_subreg_set (inner_pattern);
3573 /* Pass through the INSNS of function FNDECL and convert virtual register
3574 references to hard register references. */
3577 instantiate_virtual_regs (fndecl, insns)
3584 /* Compute the offsets to use for this function. */
3585 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3586 var_offset = STARTING_FRAME_OFFSET;
3587 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3588 out_arg_offset = STACK_POINTER_OFFSET;
3589 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3591 /* Scan all variables and parameters of this function. For each that is
3592 in memory, instantiate all virtual registers if the result is a valid
3593 address. If not, we do it later. That will handle most uses of virtual
3594 regs on many machines. */
3595 instantiate_decls (fndecl, 1);
3597 /* Initialize recognition, indicating that volatile is OK. */
3600 /* Scan through all the insns, instantiating every virtual register still
3602 for (insn = insns; insn; insn = NEXT_INSN (insn))
3603 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3604 || GET_CODE (insn) == CALL_INSN)
3606 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3607 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3608 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3609 if (GET_CODE (insn) == CALL_INSN)
3610 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3614 /* Instantiate the stack slots for the parm registers, for later use in
3615 addressof elimination. */
3616 for (i = 0; i < max_parm_reg; ++i)
3617 if (parm_reg_stack_loc[i])
3618 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3620 /* Now instantiate the remaining register equivalences for debugging info.
3621 These will not be valid addresses. */
3622 instantiate_decls (fndecl, 0);
3624 /* Indicate that, from now on, assign_stack_local should use
3625 frame_pointer_rtx. */
3626 virtuals_instantiated = 1;
3629 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3630 all virtual registers in their DECL_RTL's.
3632 If VALID_ONLY, do this only if the resulting address is still valid.
3633 Otherwise, always do it. */
3636 instantiate_decls (fndecl, valid_only)
3642 /* Process all parameters of the function. */
3643 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3645 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3646 HOST_WIDE_INT size_rtl;
3648 instantiate_decl (DECL_RTL (decl), size, valid_only);
3650 /* If the parameter was promoted, then the incoming RTL mode may be
3651 larger than the declared type size. We must use the larger of
3653 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3654 size = MAX (size_rtl, size);
3655 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3658 /* Now process all variables defined in the function or its subblocks. */
3659 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3662 /* Subroutine of instantiate_decls: Process all decls in the given
3663 BLOCK node and all its subblocks. */
3666 instantiate_decls_1 (let, valid_only)
3672 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3673 if (DECL_RTL_SET_P (t))
3674 instantiate_decl (DECL_RTL (t),
3675 int_size_in_bytes (TREE_TYPE (t)),
3678 /* Process all subblocks. */
3679 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3680 instantiate_decls_1 (t, valid_only);
3683 /* Subroutine of the preceding procedures: Given RTL representing a
3684 decl and the size of the object, do any instantiation required.
3686 If VALID_ONLY is non-zero, it means that the RTL should only be
3687 changed if the new address is valid. */
3690 instantiate_decl (x, size, valid_only)
3695 enum machine_mode mode;
3698 /* If this is not a MEM, no need to do anything. Similarly if the
3699 address is a constant or a register that is not a virtual register. */
3701 if (x == 0 || GET_CODE (x) != MEM)
3705 if (CONSTANT_P (addr)
3706 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3707 || (GET_CODE (addr) == REG
3708 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3709 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3712 /* If we should only do this if the address is valid, copy the address.
3713 We need to do this so we can undo any changes that might make the
3714 address invalid. This copy is unfortunate, but probably can't be
3718 addr = copy_rtx (addr);
3720 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3722 if (valid_only && size >= 0)
3724 unsigned HOST_WIDE_INT decl_size = size;
3726 /* Now verify that the resulting address is valid for every integer or
3727 floating-point mode up to and including SIZE bytes long. We do this
3728 since the object might be accessed in any mode and frame addresses
3731 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3732 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3733 mode = GET_MODE_WIDER_MODE (mode))
3734 if (! memory_address_p (mode, addr))
3737 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3738 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3739 mode = GET_MODE_WIDER_MODE (mode))
3740 if (! memory_address_p (mode, addr))
3744 /* Put back the address now that we have updated it and we either know
3745 it is valid or we don't care whether it is valid. */
3750 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3751 is a virtual register, return the equivalent hard register and set the
3752 offset indirectly through the pointer. Otherwise, return 0. */
3755 instantiate_new_reg (x, poffset)
3757 HOST_WIDE_INT *poffset;
3760 HOST_WIDE_INT offset;
3762 if (x == virtual_incoming_args_rtx)
3763 new = arg_pointer_rtx, offset = in_arg_offset;
3764 else if (x == virtual_stack_vars_rtx)
3765 new = frame_pointer_rtx, offset = var_offset;
3766 else if (x == virtual_stack_dynamic_rtx)
3767 new = stack_pointer_rtx, offset = dynamic_offset;
3768 else if (x == virtual_outgoing_args_rtx)
3769 new = stack_pointer_rtx, offset = out_arg_offset;
3770 else if (x == virtual_cfa_rtx)
3771 new = arg_pointer_rtx, offset = cfa_offset;
3779 /* Given a pointer to a piece of rtx and an optional pointer to the
3780 containing object, instantiate any virtual registers present in it.
3782 If EXTRA_INSNS, we always do the replacement and generate
3783 any extra insns before OBJECT. If it zero, we do nothing if replacement
3786 Return 1 if we either had nothing to do or if we were able to do the
3787 needed replacement. Return 0 otherwise; we only return zero if
3788 EXTRA_INSNS is zero.
3790 We first try some simple transformations to avoid the creation of extra
3794 instantiate_virtual_regs_1 (loc, object, extra_insns)
3802 HOST_WIDE_INT offset = 0;
3808 /* Re-start here to avoid recursion in common cases. */
3815 code = GET_CODE (x);
3817 /* Check for some special cases. */
3835 /* We are allowed to set the virtual registers. This means that
3836 the actual register should receive the source minus the
3837 appropriate offset. This is used, for example, in the handling
3838 of non-local gotos. */
3839 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3841 rtx src = SET_SRC (x);
3843 /* We are setting the register, not using it, so the relevant
3844 offset is the negative of the offset to use were we using
3847 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3849 /* The only valid sources here are PLUS or REG. Just do
3850 the simplest possible thing to handle them. */
3851 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3855 if (GET_CODE (src) != REG)
3856 temp = force_operand (src, NULL_RTX);
3859 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3863 emit_insns_before (seq, object);
3866 if (! validate_change (object, &SET_SRC (x), temp, 0)
3873 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3878 /* Handle special case of virtual register plus constant. */
3879 if (CONSTANT_P (XEXP (x, 1)))
3881 rtx old, new_offset;
3883 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3884 if (GET_CODE (XEXP (x, 0)) == PLUS)
3886 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3888 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3890 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3899 #ifdef POINTERS_EXTEND_UNSIGNED
3900 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3901 we can commute the PLUS and SUBREG because pointers into the
3902 frame are well-behaved. */
3903 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3904 && GET_CODE (XEXP (x, 1)) == CONST_INT
3906 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3908 && validate_change (object, loc,
3909 plus_constant (gen_lowpart (ptr_mode,
3912 + INTVAL (XEXP (x, 1))),
3916 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3918 /* We know the second operand is a constant. Unless the
3919 first operand is a REG (which has been already checked),
3920 it needs to be checked. */
3921 if (GET_CODE (XEXP (x, 0)) != REG)
3929 new_offset = plus_constant (XEXP (x, 1), offset);
3931 /* If the new constant is zero, try to replace the sum with just
3933 if (new_offset == const0_rtx
3934 && validate_change (object, loc, new, 0))
3937 /* Next try to replace the register and new offset.
3938 There are two changes to validate here and we can't assume that
3939 in the case of old offset equals new just changing the register
3940 will yield a valid insn. In the interests of a little efficiency,
3941 however, we only call validate change once (we don't queue up the
3942 changes and then call apply_change_group). */
3946 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3947 : (XEXP (x, 0) = new,
3948 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3956 /* Otherwise copy the new constant into a register and replace
3957 constant with that register. */
3958 temp = gen_reg_rtx (Pmode);
3960 if (validate_change (object, &XEXP (x, 1), temp, 0))
3961 emit_insn_before (gen_move_insn (temp, new_offset), object);
3964 /* If that didn't work, replace this expression with a
3965 register containing the sum. */
3968 new = gen_rtx_PLUS (Pmode, new, new_offset);
3971 temp = force_operand (new, NULL_RTX);
3975 emit_insns_before (seq, object);
3976 if (! validate_change (object, loc, temp, 0)
3977 && ! validate_replace_rtx (x, temp, object))
3985 /* Fall through to generic two-operand expression case. */
3991 case DIV: case UDIV:
3992 case MOD: case UMOD:
3993 case AND: case IOR: case XOR:
3994 case ROTATERT: case ROTATE:
3995 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3997 case GE: case GT: case GEU: case GTU:
3998 case LE: case LT: case LEU: case LTU:
3999 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
4000 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
4005 /* Most cases of MEM that convert to valid addresses have already been
4006 handled by our scan of decls. The only special handling we
4007 need here is to make a copy of the rtx to ensure it isn't being
4008 shared if we have to change it to a pseudo.
4010 If the rtx is a simple reference to an address via a virtual register,
4011 it can potentially be shared. In such cases, first try to make it
4012 a valid address, which can also be shared. Otherwise, copy it and
4015 First check for common cases that need no processing. These are
4016 usually due to instantiation already being done on a previous instance
4020 if (CONSTANT_ADDRESS_P (temp)
4021 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4022 || temp == arg_pointer_rtx
4024 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4025 || temp == hard_frame_pointer_rtx
4027 || temp == frame_pointer_rtx)
4030 if (GET_CODE (temp) == PLUS
4031 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4032 && (XEXP (temp, 0) == frame_pointer_rtx
4033 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4034 || XEXP (temp, 0) == hard_frame_pointer_rtx
4036 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4037 || XEXP (temp, 0) == arg_pointer_rtx
4042 if (temp == virtual_stack_vars_rtx
4043 || temp == virtual_incoming_args_rtx
4044 || (GET_CODE (temp) == PLUS
4045 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4046 && (XEXP (temp, 0) == virtual_stack_vars_rtx
4047 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
4049 /* This MEM may be shared. If the substitution can be done without
4050 the need to generate new pseudos, we want to do it in place
4051 so all copies of the shared rtx benefit. The call below will
4052 only make substitutions if the resulting address is still
4055 Note that we cannot pass X as the object in the recursive call
4056 since the insn being processed may not allow all valid
4057 addresses. However, if we were not passed on object, we can
4058 only modify X without copying it if X will have a valid
4061 ??? Also note that this can still lose if OBJECT is an insn that
4062 has less restrictions on an address that some other insn.
4063 In that case, we will modify the shared address. This case
4064 doesn't seem very likely, though. One case where this could
4065 happen is in the case of a USE or CLOBBER reference, but we
4066 take care of that below. */
4068 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4069 object ? object : x, 0))
4072 /* Otherwise make a copy and process that copy. We copy the entire
4073 RTL expression since it might be a PLUS which could also be
4075 *loc = x = copy_rtx (x);
4078 /* Fall through to generic unary operation case. */
4081 case STRICT_LOW_PART:
4083 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4084 case SIGN_EXTEND: case ZERO_EXTEND:
4085 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4086 case FLOAT: case FIX:
4087 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4091 /* These case either have just one operand or we know that we need not
4092 check the rest of the operands. */
4098 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4099 go ahead and make the invalid one, but do it to a copy. For a REG,
4100 just make the recursive call, since there's no chance of a problem. */
4102 if ((GET_CODE (XEXP (x, 0)) == MEM
4103 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4105 || (GET_CODE (XEXP (x, 0)) == REG
4106 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4109 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4114 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4115 in front of this insn and substitute the temporary. */
4116 if ((new = instantiate_new_reg (x, &offset)) != 0)
4118 temp = plus_constant (new, offset);
4119 if (!validate_change (object, loc, temp, 0))
4125 temp = force_operand (temp, NULL_RTX);
4129 emit_insns_before (seq, object);
4130 if (! validate_change (object, loc, temp, 0)
4131 && ! validate_replace_rtx (x, temp, object))
4139 if (GET_CODE (XEXP (x, 0)) == REG)
4142 else if (GET_CODE (XEXP (x, 0)) == MEM)
4144 /* If we have a (addressof (mem ..)), do any instantiation inside
4145 since we know we'll be making the inside valid when we finally
4146 remove the ADDRESSOF. */
4147 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4156 /* Scan all subexpressions. */
4157 fmt = GET_RTX_FORMAT (code);
4158 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4161 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4164 else if (*fmt == 'E')
4165 for (j = 0; j < XVECLEN (x, i); j++)
4166 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4173 /* Optimization: assuming this function does not receive nonlocal gotos,
4174 delete the handlers for such, as well as the insns to establish
4175 and disestablish them. */
4181 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4183 /* Delete the handler by turning off the flag that would
4184 prevent jump_optimize from deleting it.
4185 Also permit deletion of the nonlocal labels themselves
4186 if nothing local refers to them. */
4187 if (GET_CODE (insn) == CODE_LABEL)
4191 LABEL_PRESERVE_P (insn) = 0;
4193 /* Remove it from the nonlocal_label list, to avoid confusing
4195 for (t = nonlocal_labels, last_t = 0; t;
4196 last_t = t, t = TREE_CHAIN (t))
4197 if (DECL_RTL (TREE_VALUE (t)) == insn)
4202 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4204 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4207 if (GET_CODE (insn) == INSN)
4211 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4212 if (reg_mentioned_p (t, PATTERN (insn)))
4218 || (nonlocal_goto_stack_level != 0
4219 && reg_mentioned_p (nonlocal_goto_stack_level,
4221 delete_related_insns (insn);
4229 return max_parm_reg;
4232 /* Return the first insn following those generated by `assign_parms'. */
4235 get_first_nonparm_insn ()
4238 return NEXT_INSN (last_parm_insn);
4239 return get_insns ();
4242 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4243 Crash if there is none. */
4246 get_first_block_beg ()
4249 rtx insn = get_first_nonparm_insn ();
4251 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4252 if (GET_CODE (searcher) == NOTE
4253 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4256 abort (); /* Invalid call to this function. (See comments above.) */
4260 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4261 This means a type for which function calls must pass an address to the
4262 function or get an address back from the function.
4263 EXP may be a type node or an expression (whose type is tested). */
4266 aggregate_value_p (exp)
4269 int i, regno, nregs;
4272 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4274 if (TREE_CODE (type) == VOID_TYPE)
4276 if (RETURN_IN_MEMORY (type))
4278 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4279 and thus can't be returned in registers. */
4280 if (TREE_ADDRESSABLE (type))
4282 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4284 /* Make sure we have suitable call-clobbered regs to return
4285 the value in; if not, we must return it in memory. */
4286 reg = hard_function_value (type, 0, 0);
4288 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4290 if (GET_CODE (reg) != REG)
4293 regno = REGNO (reg);
4294 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4295 for (i = 0; i < nregs; i++)
4296 if (! call_used_regs[regno + i])
4301 /* Assign RTL expressions to the function's parameters.
4302 This may involve copying them into registers and using
4303 those registers as the RTL for them. */
4306 assign_parms (fndecl)
4312 CUMULATIVE_ARGS args_so_far;
4313 enum machine_mode promoted_mode, passed_mode;
4314 enum machine_mode nominal_mode, promoted_nominal_mode;
4316 /* Total space needed so far for args on the stack,
4317 given as a constant and a tree-expression. */
4318 struct args_size stack_args_size;
4319 tree fntype = TREE_TYPE (fndecl);
4320 tree fnargs = DECL_ARGUMENTS (fndecl);
4321 /* This is used for the arg pointer when referring to stack args. */
4322 rtx internal_arg_pointer;
4323 /* This is a dummy PARM_DECL that we used for the function result if
4324 the function returns a structure. */
4325 tree function_result_decl = 0;
4326 #ifdef SETUP_INCOMING_VARARGS
4327 int varargs_setup = 0;
4329 rtx conversion_insns = 0;
4330 struct args_size alignment_pad;
4332 /* Nonzero if the last arg is named `__builtin_va_alist',
4333 which is used on some machines for old-fashioned non-ANSI varargs.h;
4334 this should be stuck onto the stack as if it had arrived there. */
4336 = (current_function_varargs
4338 && (parm = tree_last (fnargs)) != 0
4340 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4341 "__builtin_va_alist")));
4343 /* Nonzero if function takes extra anonymous args.
4344 This means the last named arg must be on the stack
4345 right before the anonymous ones. */
4347 = (TYPE_ARG_TYPES (fntype) != 0
4348 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4349 != void_type_node));
4351 current_function_stdarg = stdarg;
4353 /* If the reg that the virtual arg pointer will be translated into is
4354 not a fixed reg or is the stack pointer, make a copy of the virtual
4355 arg pointer, and address parms via the copy. The frame pointer is
4356 considered fixed even though it is not marked as such.
4358 The second time through, simply use ap to avoid generating rtx. */
4360 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4361 || ! (fixed_regs[ARG_POINTER_REGNUM]
4362 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4363 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4365 internal_arg_pointer = virtual_incoming_args_rtx;
4366 current_function_internal_arg_pointer = internal_arg_pointer;
4368 stack_args_size.constant = 0;
4369 stack_args_size.var = 0;
4371 /* If struct value address is treated as the first argument, make it so. */
4372 if (aggregate_value_p (DECL_RESULT (fndecl))
4373 && ! current_function_returns_pcc_struct
4374 && struct_value_incoming_rtx == 0)
4376 tree type = build_pointer_type (TREE_TYPE (fntype));
4378 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4380 DECL_ARG_TYPE (function_result_decl) = type;
4381 TREE_CHAIN (function_result_decl) = fnargs;
4382 fnargs = function_result_decl;
4385 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4386 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4388 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4389 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4391 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4394 /* We haven't yet found an argument that we must push and pretend the
4396 current_function_pretend_args_size = 0;
4398 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4400 struct args_size stack_offset;
4401 struct args_size arg_size;
4402 int passed_pointer = 0;
4403 int did_conversion = 0;
4404 tree passed_type = DECL_ARG_TYPE (parm);
4405 tree nominal_type = TREE_TYPE (parm);
4407 int last_named = 0, named_arg;
4409 /* Set LAST_NAMED if this is last named arg before last
4411 if (stdarg || current_function_varargs)
4415 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4416 if (DECL_NAME (tem))
4422 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4423 most machines, if this is a varargs/stdarg function, then we treat
4424 the last named arg as if it were anonymous too. */
4425 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4427 if (TREE_TYPE (parm) == error_mark_node
4428 /* This can happen after weird syntax errors
4429 or if an enum type is defined among the parms. */
4430 || TREE_CODE (parm) != PARM_DECL
4431 || passed_type == NULL)
4433 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4434 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4435 TREE_USED (parm) = 1;
4439 /* For varargs.h function, save info about regs and stack space
4440 used by the individual args, not including the va_alist arg. */
4441 if (hide_last_arg && last_named)
4442 current_function_args_info = args_so_far;
4444 /* Find mode of arg as it is passed, and mode of arg
4445 as it should be during execution of this function. */
4446 passed_mode = TYPE_MODE (passed_type);
4447 nominal_mode = TYPE_MODE (nominal_type);
4449 /* If the parm's mode is VOID, its value doesn't matter,
4450 and avoid the usual things like emit_move_insn that could crash. */
4451 if (nominal_mode == VOIDmode)
4453 SET_DECL_RTL (parm, const0_rtx);
4454 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4458 /* If the parm is to be passed as a transparent union, use the
4459 type of the first field for the tests below. We have already
4460 verified that the modes are the same. */
4461 if (DECL_TRANSPARENT_UNION (parm)
4462 || (TREE_CODE (passed_type) == UNION_TYPE
4463 && TYPE_TRANSPARENT_UNION (passed_type)))
4464 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4466 /* See if this arg was passed by invisible reference. It is if
4467 it is an object whose size depends on the contents of the
4468 object itself or if the machine requires these objects be passed
4471 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4472 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4473 || TREE_ADDRESSABLE (passed_type)
4474 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4475 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4476 passed_type, named_arg)
4480 passed_type = nominal_type = build_pointer_type (passed_type);
4482 passed_mode = nominal_mode = Pmode;
4485 promoted_mode = passed_mode;
4487 #ifdef PROMOTE_FUNCTION_ARGS
4488 /* Compute the mode in which the arg is actually extended to. */
4489 unsignedp = TREE_UNSIGNED (passed_type);
4490 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4493 /* Let machine desc say which reg (if any) the parm arrives in.
4494 0 means it arrives on the stack. */
4495 #ifdef FUNCTION_INCOMING_ARG
4496 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4497 passed_type, named_arg);
4499 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4500 passed_type, named_arg);
4503 if (entry_parm == 0)
4504 promoted_mode = passed_mode;
4506 #ifdef SETUP_INCOMING_VARARGS
4507 /* If this is the last named parameter, do any required setup for
4508 varargs or stdargs. We need to know about the case of this being an
4509 addressable type, in which case we skip the registers it
4510 would have arrived in.
4512 For stdargs, LAST_NAMED will be set for two parameters, the one that
4513 is actually the last named, and the dummy parameter. We only
4514 want to do this action once.
4516 Also, indicate when RTL generation is to be suppressed. */
4517 if (last_named && !varargs_setup)
4519 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4520 current_function_pretend_args_size, 0);
4525 /* Determine parm's home in the stack,
4526 in case it arrives in the stack or we should pretend it did.
4528 Compute the stack position and rtx where the argument arrives
4531 There is one complexity here: If this was a parameter that would
4532 have been passed in registers, but wasn't only because it is
4533 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4534 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4535 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4536 0 as it was the previous time. */
4538 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4539 locate_and_pad_parm (promoted_mode, passed_type,
4540 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4543 #ifdef FUNCTION_INCOMING_ARG
4544 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4546 pretend_named) != 0,
4548 FUNCTION_ARG (args_so_far, promoted_mode,
4550 pretend_named) != 0,
4553 fndecl, &stack_args_size, &stack_offset, &arg_size,
4557 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4559 if (offset_rtx == const0_rtx)
4560 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4562 stack_parm = gen_rtx_MEM (promoted_mode,
4563 gen_rtx_PLUS (Pmode,
4564 internal_arg_pointer,
4567 set_mem_attributes (stack_parm, parm, 1);
4570 /* If this parameter was passed both in registers and in the stack,
4571 use the copy on the stack. */
4572 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4575 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4576 /* If this parm was passed part in regs and part in memory,
4577 pretend it arrived entirely in memory
4578 by pushing the register-part onto the stack.
4580 In the special case of a DImode or DFmode that is split,
4581 we could put it together in a pseudoreg directly,
4582 but for now that's not worth bothering with. */
4586 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4587 passed_type, named_arg);
4591 current_function_pretend_args_size
4592 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4593 / (PARM_BOUNDARY / BITS_PER_UNIT)
4594 * (PARM_BOUNDARY / BITS_PER_UNIT));
4596 /* Handle calls that pass values in multiple non-contiguous
4597 locations. The Irix 6 ABI has examples of this. */
4598 if (GET_CODE (entry_parm) == PARALLEL)
4599 emit_group_store (validize_mem (stack_parm), entry_parm,
4600 int_size_in_bytes (TREE_TYPE (parm)));
4603 move_block_from_reg (REGNO (entry_parm),
4604 validize_mem (stack_parm), nregs,
4605 int_size_in_bytes (TREE_TYPE (parm)));
4607 entry_parm = stack_parm;
4612 /* If we didn't decide this parm came in a register,
4613 by default it came on the stack. */
4614 if (entry_parm == 0)
4615 entry_parm = stack_parm;
4617 /* Record permanently how this parm was passed. */
4618 DECL_INCOMING_RTL (parm) = entry_parm;
4620 /* If there is actually space on the stack for this parm,
4621 count it in stack_args_size; otherwise set stack_parm to 0
4622 to indicate there is no preallocated stack slot for the parm. */
4624 if (entry_parm == stack_parm
4625 || (GET_CODE (entry_parm) == PARALLEL
4626 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4627 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4628 /* On some machines, even if a parm value arrives in a register
4629 there is still an (uninitialized) stack slot allocated for it.
4631 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4632 whether this parameter already has a stack slot allocated,
4633 because an arg block exists only if current_function_args_size
4634 is larger than some threshold, and we haven't calculated that
4635 yet. So, for now, we just assume that stack slots never exist
4637 || REG_PARM_STACK_SPACE (fndecl) > 0
4641 stack_args_size.constant += arg_size.constant;
4643 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4646 /* No stack slot was pushed for this parm. */
4649 /* Update info on where next arg arrives in registers. */
4651 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4652 passed_type, named_arg);
4654 /* If we can't trust the parm stack slot to be aligned enough
4655 for its ultimate type, don't use that slot after entry.
4656 We'll make another stack slot, if we need one. */
4658 unsigned int thisparm_boundary
4659 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4661 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4665 /* If parm was passed in memory, and we need to convert it on entry,
4666 don't store it back in that same slot. */
4668 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4671 /* When an argument is passed in multiple locations, we can't
4672 make use of this information, but we can save some copying if
4673 the whole argument is passed in a single register. */
4674 if (GET_CODE (entry_parm) == PARALLEL
4675 && nominal_mode != BLKmode && passed_mode != BLKmode)
4677 int i, len = XVECLEN (entry_parm, 0);
4679 for (i = 0; i < len; i++)
4680 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4681 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4682 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4684 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4686 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4687 DECL_INCOMING_RTL (parm) = entry_parm;
4692 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4693 in the mode in which it arrives.
4694 STACK_PARM is an RTX for a stack slot where the parameter can live
4695 during the function (in case we want to put it there).
4696 STACK_PARM is 0 if no stack slot was pushed for it.
4698 Now output code if necessary to convert ENTRY_PARM to
4699 the type in which this function declares it,
4700 and store that result in an appropriate place,
4701 which may be a pseudo reg, may be STACK_PARM,
4702 or may be a local stack slot if STACK_PARM is 0.
4704 Set DECL_RTL to that place. */
4706 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4708 /* If a BLKmode arrives in registers, copy it to a stack slot.
4709 Handle calls that pass values in multiple non-contiguous
4710 locations. The Irix 6 ABI has examples of this. */
4711 if (GET_CODE (entry_parm) == REG
4712 || GET_CODE (entry_parm) == PARALLEL)
4715 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4718 /* Note that we will be storing an integral number of words.
4719 So we have to be careful to ensure that we allocate an
4720 integral number of words. We do this below in the
4721 assign_stack_local if space was not allocated in the argument
4722 list. If it was, this will not work if PARM_BOUNDARY is not
4723 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4724 if it becomes a problem. */
4726 if (stack_parm == 0)
4729 = assign_stack_local (GET_MODE (entry_parm),
4731 set_mem_attributes (stack_parm, parm, 1);
4734 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4737 /* Handle calls that pass values in multiple non-contiguous
4738 locations. The Irix 6 ABI has examples of this. */
4739 if (GET_CODE (entry_parm) == PARALLEL)
4740 emit_group_store (validize_mem (stack_parm), entry_parm,
4741 int_size_in_bytes (TREE_TYPE (parm)));
4743 move_block_from_reg (REGNO (entry_parm),
4744 validize_mem (stack_parm),
4745 size_stored / UNITS_PER_WORD,
4746 int_size_in_bytes (TREE_TYPE (parm)));
4748 SET_DECL_RTL (parm, stack_parm);
4750 else if (! ((! optimize
4751 && ! DECL_REGISTER (parm))
4752 || TREE_SIDE_EFFECTS (parm)
4753 /* If -ffloat-store specified, don't put explicit
4754 float variables into registers. */
4755 || (flag_float_store
4756 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4757 /* Always assign pseudo to structure return or item passed
4758 by invisible reference. */
4759 || passed_pointer || parm == function_result_decl)
4761 /* Store the parm in a pseudoregister during the function, but we
4762 may need to do it in a wider mode. */
4765 unsigned int regno, regnoi = 0, regnor = 0;
4767 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4769 promoted_nominal_mode
4770 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4772 parmreg = gen_reg_rtx (promoted_nominal_mode);
4773 mark_user_reg (parmreg);
4775 /* If this was an item that we received a pointer to, set DECL_RTL
4779 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4781 set_mem_attributes (x, parm, 1);
4782 SET_DECL_RTL (parm, x);
4786 SET_DECL_RTL (parm, parmreg);
4787 maybe_set_unchanging (DECL_RTL (parm), parm);
4790 /* Copy the value into the register. */
4791 if (nominal_mode != passed_mode
4792 || promoted_nominal_mode != promoted_mode)
4795 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4796 mode, by the caller. We now have to convert it to
4797 NOMINAL_MODE, if different. However, PARMREG may be in
4798 a different mode than NOMINAL_MODE if it is being stored
4801 If ENTRY_PARM is a hard register, it might be in a register
4802 not valid for operating in its mode (e.g., an odd-numbered
4803 register for a DFmode). In that case, moves are the only
4804 thing valid, so we can't do a convert from there. This
4805 occurs when the calling sequence allow such misaligned
4808 In addition, the conversion may involve a call, which could
4809 clobber parameters which haven't been copied to pseudo
4810 registers yet. Therefore, we must first copy the parm to
4811 a pseudo reg here, and save the conversion until after all
4812 parameters have been moved. */
4814 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4816 emit_move_insn (tempreg, validize_mem (entry_parm));
4818 push_to_sequence (conversion_insns);
4819 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4821 if (GET_CODE (tempreg) == SUBREG
4822 && GET_MODE (tempreg) == nominal_mode
4823 && GET_CODE (SUBREG_REG (tempreg)) == REG
4824 && nominal_mode == passed_mode
4825 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4826 && GET_MODE_SIZE (GET_MODE (tempreg))
4827 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4829 /* The argument is already sign/zero extended, so note it
4831 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4832 SUBREG_PROMOTED_UNSIGNED_P (tempreg) = unsignedp;
4835 /* TREE_USED gets set erroneously during expand_assignment. */
4836 save_tree_used = TREE_USED (parm);
4837 expand_assignment (parm,
4838 make_tree (nominal_type, tempreg), 0, 0);
4839 TREE_USED (parm) = save_tree_used;
4840 conversion_insns = get_insns ();
4845 emit_move_insn (parmreg, validize_mem (entry_parm));
4847 /* If we were passed a pointer but the actual value
4848 can safely live in a register, put it in one. */
4849 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4850 /* If by-reference argument was promoted, demote it. */
4851 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4853 && ! DECL_REGISTER (parm))
4854 || TREE_SIDE_EFFECTS (parm)
4855 /* If -ffloat-store specified, don't put explicit
4856 float variables into registers. */
4857 || (flag_float_store
4858 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4860 /* We can't use nominal_mode, because it will have been set to
4861 Pmode above. We must use the actual mode of the parm. */
4862 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4863 mark_user_reg (parmreg);
4864 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4866 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4867 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4868 push_to_sequence (conversion_insns);
4869 emit_move_insn (tempreg, DECL_RTL (parm));
4871 convert_to_mode (GET_MODE (parmreg),
4874 emit_move_insn (parmreg, DECL_RTL (parm));
4875 conversion_insns = get_insns();
4880 emit_move_insn (parmreg, DECL_RTL (parm));
4881 SET_DECL_RTL (parm, parmreg);
4882 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4886 #ifdef FUNCTION_ARG_CALLEE_COPIES
4887 /* If we are passed an arg by reference and it is our responsibility
4888 to make a copy, do it now.
4889 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4890 original argument, so we must recreate them in the call to
4891 FUNCTION_ARG_CALLEE_COPIES. */
4892 /* ??? Later add code to handle the case that if the argument isn't
4893 modified, don't do the copy. */
4895 else if (passed_pointer
4896 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4897 TYPE_MODE (DECL_ARG_TYPE (parm)),
4898 DECL_ARG_TYPE (parm),
4900 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4903 tree type = DECL_ARG_TYPE (parm);
4905 /* This sequence may involve a library call perhaps clobbering
4906 registers that haven't been copied to pseudos yet. */
4908 push_to_sequence (conversion_insns);
4910 if (!COMPLETE_TYPE_P (type)
4911 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4912 /* This is a variable sized object. */
4913 copy = gen_rtx_MEM (BLKmode,
4914 allocate_dynamic_stack_space
4915 (expr_size (parm), NULL_RTX,
4916 TYPE_ALIGN (type)));
4918 copy = assign_stack_temp (TYPE_MODE (type),
4919 int_size_in_bytes (type), 1);
4920 set_mem_attributes (copy, parm, 1);
4922 store_expr (parm, copy, 0);
4923 emit_move_insn (parmreg, XEXP (copy, 0));
4924 conversion_insns = get_insns ();
4928 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4930 /* In any case, record the parm's desired stack location
4931 in case we later discover it must live in the stack.
4933 If it is a COMPLEX value, store the stack location for both
4936 if (GET_CODE (parmreg) == CONCAT)
4937 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4939 regno = REGNO (parmreg);
4941 if (regno >= max_parm_reg)
4944 int old_max_parm_reg = max_parm_reg;
4946 /* It's slow to expand this one register at a time,
4947 but it's also rare and we need max_parm_reg to be
4948 precisely correct. */
4949 max_parm_reg = regno + 1;
4950 new = (rtx *) xrealloc (parm_reg_stack_loc,
4951 max_parm_reg * sizeof (rtx));
4952 memset ((char *) (new + old_max_parm_reg), 0,
4953 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4954 parm_reg_stack_loc = new;
4957 if (GET_CODE (parmreg) == CONCAT)
4959 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4961 regnor = REGNO (gen_realpart (submode, parmreg));
4962 regnoi = REGNO (gen_imagpart (submode, parmreg));
4964 if (stack_parm != 0)
4966 parm_reg_stack_loc[regnor]
4967 = gen_realpart (submode, stack_parm);
4968 parm_reg_stack_loc[regnoi]
4969 = gen_imagpart (submode, stack_parm);
4973 parm_reg_stack_loc[regnor] = 0;
4974 parm_reg_stack_loc[regnoi] = 0;
4978 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4980 /* Mark the register as eliminable if we did no conversion
4981 and it was copied from memory at a fixed offset,
4982 and the arg pointer was not copied to a pseudo-reg.
4983 If the arg pointer is a pseudo reg or the offset formed
4984 an invalid address, such memory-equivalences
4985 as we make here would screw up life analysis for it. */
4986 if (nominal_mode == passed_mode
4989 && GET_CODE (stack_parm) == MEM
4990 && stack_offset.var == 0
4991 && reg_mentioned_p (virtual_incoming_args_rtx,
4992 XEXP (stack_parm, 0)))
4994 rtx linsn = get_last_insn ();
4997 /* Mark complex types separately. */
4998 if (GET_CODE (parmreg) == CONCAT)
4999 /* Scan backwards for the set of the real and
5001 for (sinsn = linsn; sinsn != 0;
5002 sinsn = prev_nonnote_insn (sinsn))
5004 set = single_set (sinsn);
5006 && SET_DEST (set) == regno_reg_rtx [regnoi])
5008 = gen_rtx_EXPR_LIST (REG_EQUIV,
5009 parm_reg_stack_loc[regnoi],
5012 && SET_DEST (set) == regno_reg_rtx [regnor])
5014 = gen_rtx_EXPR_LIST (REG_EQUIV,
5015 parm_reg_stack_loc[regnor],
5018 else if ((set = single_set (linsn)) != 0
5019 && SET_DEST (set) == parmreg)
5021 = gen_rtx_EXPR_LIST (REG_EQUIV,
5022 stack_parm, REG_NOTES (linsn));
5025 /* For pointer data type, suggest pointer register. */
5026 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5027 mark_reg_pointer (parmreg,
5028 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5030 /* If something wants our address, try to use ADDRESSOF. */
5031 if (TREE_ADDRESSABLE (parm))
5033 /* If we end up putting something into the stack,
5034 fixup_var_refs_insns will need to make a pass over
5035 all the instructions. It looks through the pending
5036 sequences -- but it can't see the ones in the
5037 CONVERSION_INSNS, if they're not on the sequence
5038 stack. So, we go back to that sequence, just so that
5039 the fixups will happen. */
5040 push_to_sequence (conversion_insns);
5041 put_var_into_stack (parm);
5042 conversion_insns = get_insns ();
5048 /* Value must be stored in the stack slot STACK_PARM
5049 during function execution. */
5051 if (promoted_mode != nominal_mode)
5053 /* Conversion is required. */
5054 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5056 emit_move_insn (tempreg, validize_mem (entry_parm));
5058 push_to_sequence (conversion_insns);
5059 entry_parm = convert_to_mode (nominal_mode, tempreg,
5060 TREE_UNSIGNED (TREE_TYPE (parm)));
5062 /* ??? This may need a big-endian conversion on sparc64. */
5063 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5065 conversion_insns = get_insns ();
5070 if (entry_parm != stack_parm)
5072 if (stack_parm == 0)
5075 = assign_stack_local (GET_MODE (entry_parm),
5076 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
5077 set_mem_attributes (stack_parm, parm, 1);
5080 if (promoted_mode != nominal_mode)
5082 push_to_sequence (conversion_insns);
5083 emit_move_insn (validize_mem (stack_parm),
5084 validize_mem (entry_parm));
5085 conversion_insns = get_insns ();
5089 emit_move_insn (validize_mem (stack_parm),
5090 validize_mem (entry_parm));
5093 SET_DECL_RTL (parm, stack_parm);
5096 /* If this "parameter" was the place where we are receiving the
5097 function's incoming structure pointer, set up the result. */
5098 if (parm == function_result_decl)
5100 tree result = DECL_RESULT (fndecl);
5101 rtx addr = DECL_RTL (parm);
5104 #ifdef POINTERS_EXTEND_UNSIGNED
5105 if (GET_MODE (addr) != Pmode)
5106 addr = convert_memory_address (Pmode, addr);
5109 x = gen_rtx_MEM (DECL_MODE (result), addr);
5110 set_mem_attributes (x, result, 1);
5111 SET_DECL_RTL (result, x);
5114 if (GET_CODE (DECL_RTL (parm)) == REG)
5115 REGNO_DECL (REGNO (DECL_RTL (parm))) = parm;
5116 else if (GET_CODE (DECL_RTL (parm)) == CONCAT)
5118 REGNO_DECL (REGNO (XEXP (DECL_RTL (parm), 0))) = parm;
5119 REGNO_DECL (REGNO (XEXP (DECL_RTL (parm), 1))) = parm;
5124 /* Output all parameter conversion instructions (possibly including calls)
5125 now that all parameters have been copied out of hard registers. */
5126 emit_insns (conversion_insns);
5128 last_parm_insn = get_last_insn ();
5130 current_function_args_size = stack_args_size.constant;
5132 /* Adjust function incoming argument size for alignment and
5135 #ifdef REG_PARM_STACK_SPACE
5136 #ifndef MAYBE_REG_PARM_STACK_SPACE
5137 current_function_args_size = MAX (current_function_args_size,
5138 REG_PARM_STACK_SPACE (fndecl));
5142 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5144 current_function_args_size
5145 = ((current_function_args_size + STACK_BYTES - 1)
5146 / STACK_BYTES) * STACK_BYTES;
5148 #ifdef ARGS_GROW_DOWNWARD
5149 current_function_arg_offset_rtx
5150 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5151 : expand_expr (size_diffop (stack_args_size.var,
5152 size_int (-stack_args_size.constant)),
5153 NULL_RTX, VOIDmode, 0));
5155 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5158 /* See how many bytes, if any, of its args a function should try to pop
5161 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5162 current_function_args_size);
5164 /* For stdarg.h function, save info about
5165 regs and stack space used by the named args. */
5168 current_function_args_info = args_so_far;
5170 /* Set the rtx used for the function return value. Put this in its
5171 own variable so any optimizers that need this information don't have
5172 to include tree.h. Do this here so it gets done when an inlined
5173 function gets output. */
5175 current_function_return_rtx
5176 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5177 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5179 /* If scalar return value was computed in a pseudo-reg, or was a named
5180 return value that got dumped to the stack, copy that to the hard
5182 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5184 tree decl_result = DECL_RESULT (fndecl);
5185 rtx decl_rtl = DECL_RTL (decl_result);
5187 if (REG_P (decl_rtl)
5188 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5189 : DECL_REGISTER (decl_result))
5193 #ifdef FUNCTION_OUTGOING_VALUE
5194 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5197 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5200 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5201 /* The delay slot scheduler assumes that current_function_return_rtx
5202 holds the hard register containing the return value, not a
5203 temporary pseudo. */
5204 current_function_return_rtx = real_decl_rtl;
5209 /* Indicate whether REGNO is an incoming argument to the current function
5210 that was promoted to a wider mode. If so, return the RTX for the
5211 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5212 that REGNO is promoted from and whether the promotion was signed or
5215 #ifdef PROMOTE_FUNCTION_ARGS
5218 promoted_input_arg (regno, pmode, punsignedp)
5220 enum machine_mode *pmode;
5225 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5226 arg = TREE_CHAIN (arg))
5227 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5228 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5229 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5231 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5232 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5234 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5235 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5236 && mode != DECL_MODE (arg))
5238 *pmode = DECL_MODE (arg);
5239 *punsignedp = unsignedp;
5240 return DECL_INCOMING_RTL (arg);
5249 /* Compute the size and offset from the start of the stacked arguments for a
5250 parm passed in mode PASSED_MODE and with type TYPE.
5252 INITIAL_OFFSET_PTR points to the current offset into the stacked
5255 The starting offset and size for this parm are returned in *OFFSET_PTR
5256 and *ARG_SIZE_PTR, respectively.
5258 IN_REGS is non-zero if the argument will be passed in registers. It will
5259 never be set if REG_PARM_STACK_SPACE is not defined.
5261 FNDECL is the function in which the argument was defined.
5263 There are two types of rounding that are done. The first, controlled by
5264 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5265 list to be aligned to the specific boundary (in bits). This rounding
5266 affects the initial and starting offsets, but not the argument size.
5268 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5269 optionally rounds the size of the parm to PARM_BOUNDARY. The
5270 initial offset is not affected by this rounding, while the size always
5271 is and the starting offset may be. */
5273 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5274 initial_offset_ptr is positive because locate_and_pad_parm's
5275 callers pass in the total size of args so far as
5276 initial_offset_ptr. arg_size_ptr is always positive. */
5279 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5280 initial_offset_ptr, offset_ptr, arg_size_ptr,
5282 enum machine_mode passed_mode;
5284 int in_regs ATTRIBUTE_UNUSED;
5285 tree fndecl ATTRIBUTE_UNUSED;
5286 struct args_size *initial_offset_ptr;
5287 struct args_size *offset_ptr;
5288 struct args_size *arg_size_ptr;
5289 struct args_size *alignment_pad;
5293 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5294 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5295 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5297 #ifdef REG_PARM_STACK_SPACE
5298 /* If we have found a stack parm before we reach the end of the
5299 area reserved for registers, skip that area. */
5302 int reg_parm_stack_space = 0;
5304 #ifdef MAYBE_REG_PARM_STACK_SPACE
5305 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5307 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5309 if (reg_parm_stack_space > 0)
5311 if (initial_offset_ptr->var)
5313 initial_offset_ptr->var
5314 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5315 ssize_int (reg_parm_stack_space));
5316 initial_offset_ptr->constant = 0;
5318 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5319 initial_offset_ptr->constant = reg_parm_stack_space;
5322 #endif /* REG_PARM_STACK_SPACE */
5324 arg_size_ptr->var = 0;
5325 arg_size_ptr->constant = 0;
5326 alignment_pad->var = 0;
5327 alignment_pad->constant = 0;
5329 #ifdef ARGS_GROW_DOWNWARD
5330 if (initial_offset_ptr->var)
5332 offset_ptr->constant = 0;
5333 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5334 initial_offset_ptr->var);
5338 offset_ptr->constant = -initial_offset_ptr->constant;
5339 offset_ptr->var = 0;
5341 if (where_pad != none
5342 && (!host_integerp (sizetree, 1)
5343 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5344 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5345 SUB_PARM_SIZE (*offset_ptr, sizetree);
5346 if (where_pad != downward)
5347 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5348 if (initial_offset_ptr->var)
5349 arg_size_ptr->var = size_binop (MINUS_EXPR,
5350 size_binop (MINUS_EXPR,
5352 initial_offset_ptr->var),
5356 arg_size_ptr->constant = (-initial_offset_ptr->constant
5357 - offset_ptr->constant);
5359 #else /* !ARGS_GROW_DOWNWARD */
5361 #ifdef REG_PARM_STACK_SPACE
5362 || REG_PARM_STACK_SPACE (fndecl) > 0
5365 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5366 *offset_ptr = *initial_offset_ptr;
5368 #ifdef PUSH_ROUNDING
5369 if (passed_mode != BLKmode)
5370 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5373 /* Pad_below needs the pre-rounded size to know how much to pad below
5374 so this must be done before rounding up. */
5375 if (where_pad == downward
5376 /* However, BLKmode args passed in regs have their padding done elsewhere.
5377 The stack slot must be able to hold the entire register. */
5378 && !(in_regs && passed_mode == BLKmode))
5379 pad_below (offset_ptr, passed_mode, sizetree);
5381 if (where_pad != none
5382 && (!host_integerp (sizetree, 1)
5383 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5384 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5386 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5387 #endif /* ARGS_GROW_DOWNWARD */
5390 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5391 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5394 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5395 struct args_size *offset_ptr;
5397 struct args_size *alignment_pad;
5399 tree save_var = NULL_TREE;
5400 HOST_WIDE_INT save_constant = 0;
5402 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5404 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5406 save_var = offset_ptr->var;
5407 save_constant = offset_ptr->constant;
5410 alignment_pad->var = NULL_TREE;
5411 alignment_pad->constant = 0;
5413 if (boundary > BITS_PER_UNIT)
5415 if (offset_ptr->var)
5418 #ifdef ARGS_GROW_DOWNWARD
5423 (ARGS_SIZE_TREE (*offset_ptr),
5424 boundary / BITS_PER_UNIT);
5425 offset_ptr->constant = 0; /*?*/
5426 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5427 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5432 offset_ptr->constant =
5433 #ifdef ARGS_GROW_DOWNWARD
5434 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5436 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5438 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5439 alignment_pad->constant = offset_ptr->constant - save_constant;
5444 #ifndef ARGS_GROW_DOWNWARD
5446 pad_below (offset_ptr, passed_mode, sizetree)
5447 struct args_size *offset_ptr;
5448 enum machine_mode passed_mode;
5451 if (passed_mode != BLKmode)
5453 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5454 offset_ptr->constant
5455 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5456 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5457 - GET_MODE_SIZE (passed_mode));
5461 if (TREE_CODE (sizetree) != INTEGER_CST
5462 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5464 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5465 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5467 ADD_PARM_SIZE (*offset_ptr, s2);
5468 SUB_PARM_SIZE (*offset_ptr, sizetree);
5474 /* Walk the tree of blocks describing the binding levels within a function
5475 and warn about uninitialized variables.
5476 This is done after calling flow_analysis and before global_alloc
5477 clobbers the pseudo-regs to hard regs. */
5480 uninitialized_vars_warning (block)
5484 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5486 if (warn_uninitialized
5487 && TREE_CODE (decl) == VAR_DECL
5488 /* These warnings are unreliable for and aggregates
5489 because assigning the fields one by one can fail to convince
5490 flow.c that the entire aggregate was initialized.
5491 Unions are troublesome because members may be shorter. */
5492 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5493 && DECL_RTL (decl) != 0
5494 && GET_CODE (DECL_RTL (decl)) == REG
5495 /* Global optimizations can make it difficult to determine if a
5496 particular variable has been initialized. However, a VAR_DECL
5497 with a nonzero DECL_INITIAL had an initializer, so do not
5498 claim it is potentially uninitialized.
5500 We do not care about the actual value in DECL_INITIAL, so we do
5501 not worry that it may be a dangling pointer. */
5502 && DECL_INITIAL (decl) == NULL_TREE
5503 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5504 warning_with_decl (decl,
5505 "`%s' might be used uninitialized in this function");
5507 && TREE_CODE (decl) == VAR_DECL
5508 && DECL_RTL (decl) != 0
5509 && GET_CODE (DECL_RTL (decl)) == REG
5510 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5511 warning_with_decl (decl,
5512 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5514 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5515 uninitialized_vars_warning (sub);
5518 /* Do the appropriate part of uninitialized_vars_warning
5519 but for arguments instead of local variables. */
5522 setjmp_args_warning ()
5525 for (decl = DECL_ARGUMENTS (current_function_decl);
5526 decl; decl = TREE_CHAIN (decl))
5527 if (DECL_RTL (decl) != 0
5528 && GET_CODE (DECL_RTL (decl)) == REG
5529 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5530 warning_with_decl (decl,
5531 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5534 /* If this function call setjmp, put all vars into the stack
5535 unless they were declared `register'. */
5538 setjmp_protect (block)
5542 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5543 if ((TREE_CODE (decl) == VAR_DECL
5544 || TREE_CODE (decl) == PARM_DECL)
5545 && DECL_RTL (decl) != 0
5546 && (GET_CODE (DECL_RTL (decl)) == REG
5547 || (GET_CODE (DECL_RTL (decl)) == MEM
5548 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5549 /* If this variable came from an inline function, it must be
5550 that its life doesn't overlap the setjmp. If there was a
5551 setjmp in the function, it would already be in memory. We
5552 must exclude such variable because their DECL_RTL might be
5553 set to strange things such as virtual_stack_vars_rtx. */
5554 && ! DECL_FROM_INLINE (decl)
5556 #ifdef NON_SAVING_SETJMP
5557 /* If longjmp doesn't restore the registers,
5558 don't put anything in them. */
5562 ! DECL_REGISTER (decl)))
5563 put_var_into_stack (decl);
5564 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5565 setjmp_protect (sub);
5568 /* Like the previous function, but for args instead of local variables. */
5571 setjmp_protect_args ()
5574 for (decl = DECL_ARGUMENTS (current_function_decl);
5575 decl; decl = TREE_CHAIN (decl))
5576 if ((TREE_CODE (decl) == VAR_DECL
5577 || TREE_CODE (decl) == PARM_DECL)
5578 && DECL_RTL (decl) != 0
5579 && (GET_CODE (DECL_RTL (decl)) == REG
5580 || (GET_CODE (DECL_RTL (decl)) == MEM
5581 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5583 /* If longjmp doesn't restore the registers,
5584 don't put anything in them. */
5585 #ifdef NON_SAVING_SETJMP
5589 ! DECL_REGISTER (decl)))
5590 put_var_into_stack (decl);
5593 /* Return the context-pointer register corresponding to DECL,
5594 or 0 if it does not need one. */
5597 lookup_static_chain (decl)
5600 tree context = decl_function_context (decl);
5604 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5607 /* We treat inline_function_decl as an alias for the current function
5608 because that is the inline function whose vars, types, etc.
5609 are being merged into the current function.
5610 See expand_inline_function. */
5611 if (context == current_function_decl || context == inline_function_decl)
5612 return virtual_stack_vars_rtx;
5614 for (link = context_display; link; link = TREE_CHAIN (link))
5615 if (TREE_PURPOSE (link) == context)
5616 return RTL_EXPR_RTL (TREE_VALUE (link));
5621 /* Convert a stack slot address ADDR for variable VAR
5622 (from a containing function)
5623 into an address valid in this function (using a static chain). */
5626 fix_lexical_addr (addr, var)
5631 HOST_WIDE_INT displacement;
5632 tree context = decl_function_context (var);
5633 struct function *fp;
5636 /* If this is the present function, we need not do anything. */
5637 if (context == current_function_decl || context == inline_function_decl)
5640 fp = find_function_data (context);
5642 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5643 addr = XEXP (XEXP (addr, 0), 0);
5645 /* Decode given address as base reg plus displacement. */
5646 if (GET_CODE (addr) == REG)
5647 basereg = addr, displacement = 0;
5648 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5649 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5653 /* We accept vars reached via the containing function's
5654 incoming arg pointer and via its stack variables pointer. */
5655 if (basereg == fp->internal_arg_pointer)
5657 /* If reached via arg pointer, get the arg pointer value
5658 out of that function's stack frame.
5660 There are two cases: If a separate ap is needed, allocate a
5661 slot in the outer function for it and dereference it that way.
5662 This is correct even if the real ap is actually a pseudo.
5663 Otherwise, just adjust the offset from the frame pointer to
5666 #ifdef NEED_SEPARATE_AP
5669 addr = get_arg_pointer_save_area (fp);
5670 addr = fix_lexical_addr (XEXP (addr, 0), var);
5671 addr = memory_address (Pmode, addr);
5673 base = gen_rtx_MEM (Pmode, addr);
5674 set_mem_alias_set (base, get_frame_alias_set ());
5675 base = copy_to_reg (base);
5677 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5678 base = lookup_static_chain (var);
5682 else if (basereg == virtual_stack_vars_rtx)
5684 /* This is the same code as lookup_static_chain, duplicated here to
5685 avoid an extra call to decl_function_context. */
5688 for (link = context_display; link; link = TREE_CHAIN (link))
5689 if (TREE_PURPOSE (link) == context)
5691 base = RTL_EXPR_RTL (TREE_VALUE (link));
5699 /* Use same offset, relative to appropriate static chain or argument
5701 return plus_constant (base, displacement);
5704 /* Return the address of the trampoline for entering nested fn FUNCTION.
5705 If necessary, allocate a trampoline (in the stack frame)
5706 and emit rtl to initialize its contents (at entry to this function). */
5709 trampoline_address (function)
5715 struct function *fp;
5718 /* Find an existing trampoline and return it. */
5719 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5720 if (TREE_PURPOSE (link) == function)
5722 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5724 for (fp = outer_function_chain; fp; fp = fp->outer)
5725 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5726 if (TREE_PURPOSE (link) == function)
5728 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5730 return adjust_trampoline_addr (tramp);
5733 /* None exists; we must make one. */
5735 /* Find the `struct function' for the function containing FUNCTION. */
5737 fn_context = decl_function_context (function);
5738 if (fn_context != current_function_decl
5739 && fn_context != inline_function_decl)
5740 fp = find_function_data (fn_context);
5742 /* Allocate run-time space for this trampoline
5743 (usually in the defining function's stack frame). */
5744 #ifdef ALLOCATE_TRAMPOLINE
5745 tramp = ALLOCATE_TRAMPOLINE (fp);
5747 /* If rounding needed, allocate extra space
5748 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5749 #ifdef TRAMPOLINE_ALIGNMENT
5750 #define TRAMPOLINE_REAL_SIZE \
5751 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5753 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5755 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5759 /* Record the trampoline for reuse and note it for later initialization
5760 by expand_function_end. */
5763 rtlexp = make_node (RTL_EXPR);
5764 RTL_EXPR_RTL (rtlexp) = tramp;
5765 fp->x_trampoline_list = tree_cons (function, rtlexp,
5766 fp->x_trampoline_list);
5770 /* Make the RTL_EXPR node temporary, not momentary, so that the
5771 trampoline_list doesn't become garbage. */
5772 rtlexp = make_node (RTL_EXPR);
5774 RTL_EXPR_RTL (rtlexp) = tramp;
5775 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5778 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5779 return adjust_trampoline_addr (tramp);
5782 /* Given a trampoline address,
5783 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5786 round_trampoline_addr (tramp)
5789 #ifdef TRAMPOLINE_ALIGNMENT
5790 /* Round address up to desired boundary. */
5791 rtx temp = gen_reg_rtx (Pmode);
5792 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5793 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5795 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5796 temp, 0, OPTAB_LIB_WIDEN);
5797 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5798 temp, 0, OPTAB_LIB_WIDEN);
5803 /* Given a trampoline address, round it then apply any
5804 platform-specific adjustments so that the result can be used for a
5808 adjust_trampoline_addr (tramp)
5811 tramp = round_trampoline_addr (tramp);
5812 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5813 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5818 /* Put all this function's BLOCK nodes including those that are chained
5819 onto the first block into a vector, and return it.
5820 Also store in each NOTE for the beginning or end of a block
5821 the index of that block in the vector.
5822 The arguments are BLOCK, the chain of top-level blocks of the function,
5823 and INSNS, the insn chain of the function. */
5829 tree *block_vector, *last_block_vector;
5831 tree block = DECL_INITIAL (current_function_decl);
5836 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5837 depth-first order. */
5838 block_vector = get_block_vector (block, &n_blocks);
5839 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5841 last_block_vector = identify_blocks_1 (get_insns (),
5843 block_vector + n_blocks,
5846 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5847 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5848 if (0 && last_block_vector != block_vector + n_blocks)
5851 free (block_vector);
5855 /* Subroutine of identify_blocks. Do the block substitution on the
5856 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5858 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5859 BLOCK_VECTOR is incremented for each block seen. */
5862 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5865 tree *end_block_vector;
5866 tree *orig_block_stack;
5869 tree *block_stack = orig_block_stack;
5871 for (insn = insns; insn; insn = NEXT_INSN (insn))
5873 if (GET_CODE (insn) == NOTE)
5875 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5879 /* If there are more block notes than BLOCKs, something
5881 if (block_vector == end_block_vector)
5884 b = *block_vector++;
5885 NOTE_BLOCK (insn) = b;
5888 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5890 /* If there are more NOTE_INSN_BLOCK_ENDs than
5891 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5892 if (block_stack == orig_block_stack)
5895 NOTE_BLOCK (insn) = *--block_stack;
5898 else if (GET_CODE (insn) == CALL_INSN
5899 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5901 rtx cp = PATTERN (insn);
5903 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5904 end_block_vector, block_stack);
5906 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5907 end_block_vector, block_stack);
5909 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5910 end_block_vector, block_stack);
5914 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5915 something is badly wrong. */
5916 if (block_stack != orig_block_stack)
5919 return block_vector;
5922 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5923 and create duplicate blocks. */
5924 /* ??? Need an option to either create block fragments or to create
5925 abstract origin duplicates of a source block. It really depends
5926 on what optimization has been performed. */
5931 tree block = DECL_INITIAL (current_function_decl);
5932 varray_type block_stack;
5934 if (block == NULL_TREE)
5937 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5939 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5940 reorder_blocks_0 (block);
5942 /* Prune the old trees away, so that they don't get in the way. */
5943 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5944 BLOCK_CHAIN (block) = NULL_TREE;
5946 /* Recreate the block tree from the note nesting. */
5947 reorder_blocks_1 (get_insns (), block, &block_stack);
5948 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5950 /* Remove deleted blocks from the block fragment chains. */
5951 reorder_fix_fragments (block);
5953 VARRAY_FREE (block_stack);
5956 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5959 reorder_blocks_0 (block)
5964 TREE_ASM_WRITTEN (block) = 0;
5965 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5966 block = BLOCK_CHAIN (block);
5971 reorder_blocks_1 (insns, current_block, p_block_stack)
5974 varray_type *p_block_stack;
5978 for (insn = insns; insn; insn = NEXT_INSN (insn))
5980 if (GET_CODE (insn) == NOTE)
5982 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5984 tree block = NOTE_BLOCK (insn);
5986 /* If we have seen this block before, that means it now
5987 spans multiple address regions. Create a new fragment. */
5988 if (TREE_ASM_WRITTEN (block))
5990 tree new_block = copy_node (block);
5993 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5994 ? BLOCK_FRAGMENT_ORIGIN (block)
5996 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5997 BLOCK_FRAGMENT_CHAIN (new_block)
5998 = BLOCK_FRAGMENT_CHAIN (origin);
5999 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
6001 NOTE_BLOCK (insn) = new_block;
6005 BLOCK_SUBBLOCKS (block) = 0;
6006 TREE_ASM_WRITTEN (block) = 1;
6007 BLOCK_SUPERCONTEXT (block) = current_block;
6008 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6009 BLOCK_SUBBLOCKS (current_block) = block;
6010 current_block = block;
6011 VARRAY_PUSH_TREE (*p_block_stack, block);
6013 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6015 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6016 VARRAY_POP (*p_block_stack);
6017 BLOCK_SUBBLOCKS (current_block)
6018 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6019 current_block = BLOCK_SUPERCONTEXT (current_block);
6022 else if (GET_CODE (insn) == CALL_INSN
6023 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6025 rtx cp = PATTERN (insn);
6026 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
6028 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6030 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6035 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6036 appears in the block tree, select one of the fragments to become
6037 the new origin block. */
6040 reorder_fix_fragments (block)
6045 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6046 tree new_origin = NULL_TREE;
6050 if (! TREE_ASM_WRITTEN (dup_origin))
6052 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6054 /* Find the first of the remaining fragments. There must
6055 be at least one -- the current block. */
6056 while (! TREE_ASM_WRITTEN (new_origin))
6057 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6058 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6061 else if (! dup_origin)
6064 /* Re-root the rest of the fragments to the new origin. In the
6065 case that DUP_ORIGIN was null, that means BLOCK was the origin
6066 of a chain of fragments and we want to remove those fragments
6067 that didn't make it to the output. */
6070 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6075 if (TREE_ASM_WRITTEN (chain))
6077 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6079 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6081 chain = BLOCK_FRAGMENT_CHAIN (chain);
6086 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6087 block = BLOCK_CHAIN (block);
6091 /* Reverse the order of elements in the chain T of blocks,
6092 and return the new head of the chain (old last element). */
6098 tree prev = 0, decl, next;
6099 for (decl = t; decl; decl = next)
6101 next = BLOCK_CHAIN (decl);
6102 BLOCK_CHAIN (decl) = prev;
6108 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6109 non-NULL, list them all into VECTOR, in a depth-first preorder
6110 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6114 all_blocks (block, vector)
6122 TREE_ASM_WRITTEN (block) = 0;
6124 /* Record this block. */
6126 vector[n_blocks] = block;
6130 /* Record the subblocks, and their subblocks... */
6131 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6132 vector ? vector + n_blocks : 0);
6133 block = BLOCK_CHAIN (block);
6139 /* Return a vector containing all the blocks rooted at BLOCK. The
6140 number of elements in the vector is stored in N_BLOCKS_P. The
6141 vector is dynamically allocated; it is the caller's responsibility
6142 to call `free' on the pointer returned. */
6145 get_block_vector (block, n_blocks_p)
6151 *n_blocks_p = all_blocks (block, NULL);
6152 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6153 all_blocks (block, block_vector);
6155 return block_vector;
6158 static int next_block_index = 2;
6160 /* Set BLOCK_NUMBER for all the blocks in FN. */
6170 /* For SDB and XCOFF debugging output, we start numbering the blocks
6171 from 1 within each function, rather than keeping a running
6173 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6174 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6175 next_block_index = 1;
6178 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6180 /* The top-level BLOCK isn't numbered at all. */
6181 for (i = 1; i < n_blocks; ++i)
6182 /* We number the blocks from two. */
6183 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6185 free (block_vector);
6190 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6193 debug_find_var_in_block_tree (var, block)
6199 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6203 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6205 tree ret = debug_find_var_in_block_tree (var, t);
6213 /* Allocate a function structure and reset its contents to the defaults. */
6216 prepare_function_start ()
6218 cfun = (struct function *) ggc_alloc_cleared (sizeof (struct function));
6220 init_stmt_for_function ();
6221 init_eh_for_function ();
6223 cse_not_expected = ! optimize;
6225 /* Caller save not needed yet. */
6226 caller_save_needed = 0;
6228 /* No stack slots have been made yet. */
6229 stack_slot_list = 0;
6231 current_function_has_nonlocal_label = 0;
6232 current_function_has_nonlocal_goto = 0;
6234 /* There is no stack slot for handling nonlocal gotos. */
6235 nonlocal_goto_handler_slots = 0;
6236 nonlocal_goto_stack_level = 0;
6238 /* No labels have been declared for nonlocal use. */
6239 nonlocal_labels = 0;
6240 nonlocal_goto_handler_labels = 0;
6242 /* No function calls so far in this function. */
6243 function_call_count = 0;
6245 /* No parm regs have been allocated.
6246 (This is important for output_inline_function.) */
6247 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6249 /* Initialize the RTL mechanism. */
6252 /* Initialize the queue of pending postincrement and postdecrements,
6253 and some other info in expr.c. */
6256 /* We haven't done register allocation yet. */
6259 init_varasm_status (cfun);
6261 /* Clear out data used for inlining. */
6262 cfun->inlinable = 0;
6263 cfun->original_decl_initial = 0;
6264 cfun->original_arg_vector = 0;
6266 cfun->stack_alignment_needed = STACK_BOUNDARY;
6267 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6269 /* Set if a call to setjmp is seen. */
6270 current_function_calls_setjmp = 0;
6272 /* Set if a call to longjmp is seen. */
6273 current_function_calls_longjmp = 0;
6275 current_function_calls_alloca = 0;
6276 current_function_contains_functions = 0;
6277 current_function_is_leaf = 0;
6278 current_function_nothrow = 0;
6279 current_function_sp_is_unchanging = 0;
6280 current_function_uses_only_leaf_regs = 0;
6281 current_function_has_computed_jump = 0;
6282 current_function_is_thunk = 0;
6284 current_function_returns_pcc_struct = 0;
6285 current_function_returns_struct = 0;
6286 current_function_epilogue_delay_list = 0;
6287 current_function_uses_const_pool = 0;
6288 current_function_uses_pic_offset_table = 0;
6289 current_function_cannot_inline = 0;
6291 /* We have not yet needed to make a label to jump to for tail-recursion. */
6292 tail_recursion_label = 0;
6294 /* We haven't had a need to make a save area for ap yet. */
6295 arg_pointer_save_area = 0;
6297 /* No stack slots allocated yet. */
6300 /* No SAVE_EXPRs in this function yet. */
6303 /* No RTL_EXPRs in this function yet. */
6306 /* Set up to allocate temporaries. */
6309 /* Indicate that we need to distinguish between the return value of the
6310 present function and the return value of a function being called. */
6311 rtx_equal_function_value_matters = 1;
6313 /* Indicate that we have not instantiated virtual registers yet. */
6314 virtuals_instantiated = 0;
6316 /* Indicate that we want CONCATs now. */
6317 generating_concat_p = 1;
6319 /* Indicate we have no need of a frame pointer yet. */
6320 frame_pointer_needed = 0;
6322 /* By default assume not varargs or stdarg. */
6323 current_function_varargs = 0;
6324 current_function_stdarg = 0;
6326 /* We haven't made any trampolines for this function yet. */
6327 trampoline_list = 0;
6329 init_pending_stack_adjust ();
6330 inhibit_defer_pop = 0;
6332 current_function_outgoing_args_size = 0;
6334 if (init_lang_status)
6335 (*init_lang_status) (cfun);
6336 if (init_machine_status)
6337 (*init_machine_status) (cfun);
6340 /* Initialize the rtl expansion mechanism so that we can do simple things
6341 like generate sequences. This is used to provide a context during global
6342 initialization of some passes. */
6344 init_dummy_function_start ()
6346 prepare_function_start ();
6349 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6350 and initialize static variables for generating RTL for the statements
6354 init_function_start (subr, filename, line)
6356 const char *filename;
6359 prepare_function_start ();
6361 current_function_name = (*decl_printable_name) (subr, 2);
6364 /* Nonzero if this is a nested function that uses a static chain. */
6366 current_function_needs_context
6367 = (decl_function_context (current_function_decl) != 0
6368 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6370 /* Within function body, compute a type's size as soon it is laid out. */
6371 immediate_size_expand++;
6373 /* Prevent ever trying to delete the first instruction of a function.
6374 Also tell final how to output a linenum before the function prologue.
6375 Note linenums could be missing, e.g. when compiling a Java .class file. */
6377 emit_line_note (filename, line);
6379 /* Make sure first insn is a note even if we don't want linenums.
6380 This makes sure the first insn will never be deleted.
6381 Also, final expects a note to appear there. */
6382 emit_note (NULL, NOTE_INSN_DELETED);
6384 /* Set flags used by final.c. */
6385 if (aggregate_value_p (DECL_RESULT (subr)))
6387 #ifdef PCC_STATIC_STRUCT_RETURN
6388 current_function_returns_pcc_struct = 1;
6390 current_function_returns_struct = 1;
6393 /* Warn if this value is an aggregate type,
6394 regardless of which calling convention we are using for it. */
6395 if (warn_aggregate_return
6396 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6397 warning ("function returns an aggregate");
6399 current_function_returns_pointer
6400 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6403 /* Make sure all values used by the optimization passes have sane
6406 init_function_for_compilation ()
6410 /* No prologue/epilogue insns yet. */
6411 VARRAY_GROW (prologue, 0);
6412 VARRAY_GROW (epilogue, 0);
6413 VARRAY_GROW (sibcall_epilogue, 0);
6416 /* Indicate that the current function uses extra args
6417 not explicitly mentioned in the argument list in any fashion. */
6422 current_function_varargs = 1;
6425 /* Expand a call to __main at the beginning of a possible main function. */
6427 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6428 #undef HAS_INIT_SECTION
6429 #define HAS_INIT_SECTION
6432 #ifndef GEN_CALL__MAIN
6433 #define GEN_CALL__MAIN \
6435 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), LCT_NORMAL, \
6441 expand_main_function ()
6443 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6444 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6446 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6450 /* Forcibly align the stack. */
6451 #ifdef STACK_GROWS_DOWNWARD
6452 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6453 stack_pointer_rtx, 1, OPTAB_WIDEN);
6455 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6456 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6457 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6458 stack_pointer_rtx, 1, OPTAB_WIDEN);
6460 if (tmp != stack_pointer_rtx)
6461 emit_move_insn (stack_pointer_rtx, tmp);
6463 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6464 tmp = force_reg (Pmode, const0_rtx);
6465 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6466 seq = gen_sequence ();
6469 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6470 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6473 emit_insn_before (seq, tmp);
6479 #if defined(INVOKE__main) || !defined (HAS_INIT_SECTION)
6484 extern struct obstack permanent_obstack;
6486 /* The PENDING_SIZES represent the sizes of variable-sized types.
6487 Create RTL for the various sizes now (using temporary variables),
6488 so that we can refer to the sizes from the RTL we are generating
6489 for the current function. The PENDING_SIZES are a TREE_LIST. The
6490 TREE_VALUE of each node is a SAVE_EXPR. */
6493 expand_pending_sizes (pending_sizes)
6498 /* Evaluate now the sizes of any types declared among the arguments. */
6499 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6501 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6502 /* Flush the queue in case this parameter declaration has
6508 /* Start the RTL for a new function, and set variables used for
6510 SUBR is the FUNCTION_DECL node.
6511 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6512 the function's parameters, which must be run at any return statement. */
6515 expand_function_start (subr, parms_have_cleanups)
6517 int parms_have_cleanups;
6520 rtx last_ptr = NULL_RTX;
6522 /* Make sure volatile mem refs aren't considered
6523 valid operands of arithmetic insns. */
6524 init_recog_no_volatile ();
6526 current_function_instrument_entry_exit
6527 = (flag_instrument_function_entry_exit
6528 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6530 current_function_profile
6532 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6534 current_function_limit_stack
6535 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6537 /* If function gets a static chain arg, store it in the stack frame.
6538 Do this first, so it gets the first stack slot offset. */
6539 if (current_function_needs_context)
6541 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6543 /* Delay copying static chain if it is not a register to avoid
6544 conflicts with regs used for parameters. */
6545 if (! SMALL_REGISTER_CLASSES
6546 || GET_CODE (static_chain_incoming_rtx) == REG)
6547 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6550 /* If the parameters of this function need cleaning up, get a label
6551 for the beginning of the code which executes those cleanups. This must
6552 be done before doing anything with return_label. */
6553 if (parms_have_cleanups)
6554 cleanup_label = gen_label_rtx ();
6558 /* Make the label for return statements to jump to. Do not special
6559 case machines with special return instructions -- they will be
6560 handled later during jump, ifcvt, or epilogue creation. */
6561 return_label = gen_label_rtx ();
6563 /* Initialize rtx used to return the value. */
6564 /* Do this before assign_parms so that we copy the struct value address
6565 before any library calls that assign parms might generate. */
6567 /* Decide whether to return the value in memory or in a register. */
6568 if (aggregate_value_p (DECL_RESULT (subr)))
6570 /* Returning something that won't go in a register. */
6571 rtx value_address = 0;
6573 #ifdef PCC_STATIC_STRUCT_RETURN
6574 if (current_function_returns_pcc_struct)
6576 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6577 value_address = assemble_static_space (size);
6582 /* Expect to be passed the address of a place to store the value.
6583 If it is passed as an argument, assign_parms will take care of
6585 if (struct_value_incoming_rtx)
6587 value_address = gen_reg_rtx (Pmode);
6588 emit_move_insn (value_address, struct_value_incoming_rtx);
6593 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6594 set_mem_attributes (x, DECL_RESULT (subr), 1);
6595 SET_DECL_RTL (DECL_RESULT (subr), x);
6598 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6599 /* If return mode is void, this decl rtl should not be used. */
6600 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6603 /* Compute the return values into a pseudo reg, which we will copy
6604 into the true return register after the cleanups are done. */
6606 /* In order to figure out what mode to use for the pseudo, we
6607 figure out what the mode of the eventual return register will
6608 actually be, and use that. */
6610 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6613 /* Structures that are returned in registers are not aggregate_value_p,
6614 so we may see a PARALLEL. Don't play pseudo games with this. */
6615 if (! REG_P (hard_reg))
6616 SET_DECL_RTL (DECL_RESULT (subr), hard_reg);
6619 /* Create the pseudo. */
6620 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6622 /* Needed because we may need to move this to memory
6623 in case it's a named return value whose address is taken. */
6624 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6628 /* Initialize rtx for parameters and local variables.
6629 In some cases this requires emitting insns. */
6631 assign_parms (subr);
6633 /* Copy the static chain now if it wasn't a register. The delay is to
6634 avoid conflicts with the parameter passing registers. */
6636 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6637 if (GET_CODE (static_chain_incoming_rtx) != REG)
6638 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6640 /* The following was moved from init_function_start.
6641 The move is supposed to make sdb output more accurate. */
6642 /* Indicate the beginning of the function body,
6643 as opposed to parm setup. */
6644 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6646 if (GET_CODE (get_last_insn ()) != NOTE)
6647 emit_note (NULL, NOTE_INSN_DELETED);
6648 parm_birth_insn = get_last_insn ();
6650 context_display = 0;
6651 if (current_function_needs_context)
6653 /* Fetch static chain values for containing functions. */
6654 tem = decl_function_context (current_function_decl);
6655 /* Copy the static chain pointer into a pseudo. If we have
6656 small register classes, copy the value from memory if
6657 static_chain_incoming_rtx is a REG. */
6660 /* If the static chain originally came in a register, put it back
6661 there, then move it out in the next insn. The reason for
6662 this peculiar code is to satisfy function integration. */
6663 if (SMALL_REGISTER_CLASSES
6664 && GET_CODE (static_chain_incoming_rtx) == REG)
6665 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6666 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6671 tree rtlexp = make_node (RTL_EXPR);
6673 RTL_EXPR_RTL (rtlexp) = last_ptr;
6674 context_display = tree_cons (tem, rtlexp, context_display);
6675 tem = decl_function_context (tem);
6678 /* Chain thru stack frames, assuming pointer to next lexical frame
6679 is found at the place we always store it. */
6680 #ifdef FRAME_GROWS_DOWNWARD
6681 last_ptr = plus_constant (last_ptr,
6682 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6684 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6685 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6686 last_ptr = copy_to_reg (last_ptr);
6688 /* If we are not optimizing, ensure that we know that this
6689 piece of context is live over the entire function. */
6691 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6696 if (current_function_instrument_entry_exit)
6698 rtx fun = DECL_RTL (current_function_decl);
6699 if (GET_CODE (fun) == MEM)
6700 fun = XEXP (fun, 0);
6703 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6705 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6707 hard_frame_pointer_rtx),
6711 if (current_function_profile)
6713 current_function_profile_label_no = profile_label_no++;
6715 PROFILE_HOOK (current_function_profile_label_no);
6719 /* After the display initializations is where the tail-recursion label
6720 should go, if we end up needing one. Ensure we have a NOTE here
6721 since some things (like trampolines) get placed before this. */
6722 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6724 /* Evaluate now the sizes of any types declared among the arguments. */
6725 expand_pending_sizes (nreverse (get_pending_sizes ()));
6727 /* Make sure there is a line number after the function entry setup code. */
6728 force_next_line_note ();
6731 /* Undo the effects of init_dummy_function_start. */
6733 expand_dummy_function_end ()
6735 /* End any sequences that failed to be closed due to syntax errors. */
6736 while (in_sequence_p ())
6739 /* Outside function body, can't compute type's actual size
6740 until next function's body starts. */
6742 free_after_parsing (cfun);
6743 free_after_compilation (cfun);
6747 /* Call DOIT for each hard register used as a return value from
6748 the current function. */
6751 diddle_return_value (doit, arg)
6752 void (*doit) PARAMS ((rtx, void *));
6755 rtx outgoing = current_function_return_rtx;
6760 if (GET_CODE (outgoing) == REG)
6761 (*doit) (outgoing, arg);
6762 else if (GET_CODE (outgoing) == PARALLEL)
6766 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6768 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6770 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6777 do_clobber_return_reg (reg, arg)
6779 void *arg ATTRIBUTE_UNUSED;
6781 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6785 clobber_return_register ()
6787 diddle_return_value (do_clobber_return_reg, NULL);
6789 /* In case we do use pseudo to return value, clobber it too. */
6790 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6792 tree decl_result = DECL_RESULT (current_function_decl);
6793 rtx decl_rtl = DECL_RTL (decl_result);
6794 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6796 do_clobber_return_reg (decl_rtl, NULL);
6802 do_use_return_reg (reg, arg)
6804 void *arg ATTRIBUTE_UNUSED;
6806 emit_insn (gen_rtx_USE (VOIDmode, reg));
6810 use_return_register ()
6812 diddle_return_value (do_use_return_reg, NULL);
6815 /* Generate RTL for the end of the current function.
6816 FILENAME and LINE are the current position in the source file.
6818 It is up to language-specific callers to do cleanups for parameters--
6819 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6822 expand_function_end (filename, line, end_bindings)
6823 const char *filename;
6830 #ifdef TRAMPOLINE_TEMPLATE
6831 static rtx initial_trampoline;
6834 finish_expr_for_function ();
6836 /* If arg_pointer_save_area was referenced only from a nested
6837 function, we will not have initialized it yet. Do that now. */
6838 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6839 get_arg_pointer_save_area (cfun);
6841 #ifdef NON_SAVING_SETJMP
6842 /* Don't put any variables in registers if we call setjmp
6843 on a machine that fails to restore the registers. */
6844 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6846 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6847 setjmp_protect (DECL_INITIAL (current_function_decl));
6849 setjmp_protect_args ();
6853 /* Initialize any trampolines required by this function. */
6854 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6856 tree function = TREE_PURPOSE (link);
6857 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6858 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6859 #ifdef TRAMPOLINE_TEMPLATE
6864 #ifdef TRAMPOLINE_TEMPLATE
6865 /* First make sure this compilation has a template for
6866 initializing trampolines. */
6867 if (initial_trampoline == 0)
6870 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6871 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6873 ggc_add_rtx_root (&initial_trampoline, 1);
6877 /* Generate insns to initialize the trampoline. */
6879 tramp = round_trampoline_addr (XEXP (tramp, 0));
6880 #ifdef TRAMPOLINE_TEMPLATE
6881 blktramp = replace_equiv_address (initial_trampoline, tramp);
6882 emit_block_move (blktramp, initial_trampoline,
6883 GEN_INT (TRAMPOLINE_SIZE));
6885 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6889 /* Put those insns at entry to the containing function (this one). */
6890 emit_insns_before (seq, tail_recursion_reentry);
6893 /* If we are doing stack checking and this function makes calls,
6894 do a stack probe at the start of the function to ensure we have enough
6895 space for another stack frame. */
6896 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6900 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6901 if (GET_CODE (insn) == CALL_INSN)
6904 probe_stack_range (STACK_CHECK_PROTECT,
6905 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6908 emit_insns_before (seq, tail_recursion_reentry);
6913 /* Warn about unused parms if extra warnings were specified. */
6914 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6915 warning. WARN_UNUSED_PARAMETER is negative when set by
6917 if (warn_unused_parameter > 0
6918 || (warn_unused_parameter < 0 && extra_warnings))
6922 for (decl = DECL_ARGUMENTS (current_function_decl);
6923 decl; decl = TREE_CHAIN (decl))
6924 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6925 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6926 warning_with_decl (decl, "unused parameter `%s'");
6929 /* Delete handlers for nonlocal gotos if nothing uses them. */
6930 if (nonlocal_goto_handler_slots != 0
6931 && ! current_function_has_nonlocal_label)
6934 /* End any sequences that failed to be closed due to syntax errors. */
6935 while (in_sequence_p ())
6938 /* Outside function body, can't compute type's actual size
6939 until next function's body starts. */
6940 immediate_size_expand--;
6942 clear_pending_stack_adjust ();
6943 do_pending_stack_adjust ();
6945 /* Mark the end of the function body.
6946 If control reaches this insn, the function can drop through
6947 without returning a value. */
6948 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6950 /* Must mark the last line number note in the function, so that the test
6951 coverage code can avoid counting the last line twice. This just tells
6952 the code to ignore the immediately following line note, since there
6953 already exists a copy of this note somewhere above. This line number
6954 note is still needed for debugging though, so we can't delete it. */
6955 if (flag_test_coverage)
6956 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6958 /* Output a linenumber for the end of the function.
6959 SDB depends on this. */
6960 emit_line_note_force (filename, line);
6962 /* Before the return label (if any), clobber the return
6963 registers so that they are not propagated live to the rest of
6964 the function. This can only happen with functions that drop
6965 through; if there had been a return statement, there would
6966 have either been a return rtx, or a jump to the return label.
6968 We delay actual code generation after the current_function_value_rtx
6970 clobber_after = get_last_insn ();
6972 /* Output the label for the actual return from the function,
6973 if one is expected. This happens either because a function epilogue
6974 is used instead of a return instruction, or because a return was done
6975 with a goto in order to run local cleanups, or because of pcc-style
6976 structure returning. */
6978 emit_label (return_label);
6980 /* C++ uses this. */
6982 expand_end_bindings (0, 0, 0);
6984 if (current_function_instrument_entry_exit)
6986 rtx fun = DECL_RTL (current_function_decl);
6987 if (GET_CODE (fun) == MEM)
6988 fun = XEXP (fun, 0);
6991 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6993 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6995 hard_frame_pointer_rtx),
6999 /* Let except.c know where it should emit the call to unregister
7000 the function context for sjlj exceptions. */
7001 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
7002 sjlj_emit_function_exit_after (get_last_insn ());
7004 /* If we had calls to alloca, and this machine needs
7005 an accurate stack pointer to exit the function,
7006 insert some code to save and restore the stack pointer. */
7007 #ifdef EXIT_IGNORE_STACK
7008 if (! EXIT_IGNORE_STACK)
7010 if (current_function_calls_alloca)
7014 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
7015 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
7018 /* If scalar return value was computed in a pseudo-reg, or was a named
7019 return value that got dumped to the stack, copy that to the hard
7021 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
7023 tree decl_result = DECL_RESULT (current_function_decl);
7024 rtx decl_rtl = DECL_RTL (decl_result);
7026 if (REG_P (decl_rtl)
7027 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
7028 : DECL_REGISTER (decl_result))
7030 rtx real_decl_rtl = current_function_return_rtx;
7032 /* This should be set in assign_parms. */
7033 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
7036 /* If this is a BLKmode structure being returned in registers,
7037 then use the mode computed in expand_return. Note that if
7038 decl_rtl is memory, then its mode may have been changed,
7039 but that current_function_return_rtx has not. */
7040 if (GET_MODE (real_decl_rtl) == BLKmode)
7041 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
7043 /* If a named return value dumped decl_return to memory, then
7044 we may need to re-do the PROMOTE_MODE signed/unsigned
7046 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
7048 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
7050 #ifdef PROMOTE_FUNCTION_RETURN
7051 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7055 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7057 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7058 emit_group_load (real_decl_rtl, decl_rtl,
7059 int_size_in_bytes (TREE_TYPE (decl_result)));
7061 emit_move_insn (real_decl_rtl, decl_rtl);
7065 /* If returning a structure, arrange to return the address of the value
7066 in a place where debuggers expect to find it.
7068 If returning a structure PCC style,
7069 the caller also depends on this value.
7070 And current_function_returns_pcc_struct is not necessarily set. */
7071 if (current_function_returns_struct
7072 || current_function_returns_pcc_struct)
7075 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7076 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7077 #ifdef FUNCTION_OUTGOING_VALUE
7079 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7080 current_function_decl);
7083 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7086 /* Mark this as a function return value so integrate will delete the
7087 assignment and USE below when inlining this function. */
7088 REG_FUNCTION_VALUE_P (outgoing) = 1;
7090 #ifdef POINTERS_EXTEND_UNSIGNED
7091 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7092 if (GET_MODE (outgoing) != GET_MODE (value_address))
7093 value_address = convert_memory_address (GET_MODE (outgoing),
7097 emit_move_insn (outgoing, value_address);
7099 /* Show return register used to hold result (in this case the address
7101 current_function_return_rtx = outgoing;
7104 /* If this is an implementation of throw, do what's necessary to
7105 communicate between __builtin_eh_return and the epilogue. */
7106 expand_eh_return ();
7108 /* Emit the actual code to clobber return register. */
7113 clobber_return_register ();
7114 seq = gen_sequence ();
7117 after = emit_insn_after (seq, clobber_after);
7119 if (clobber_after != after)
7120 cfun->x_clobber_return_insn = after;
7123 /* ??? This should no longer be necessary since stupid is no longer with
7124 us, but there are some parts of the compiler (eg reload_combine, and
7125 sh mach_dep_reorg) that still try and compute their own lifetime info
7126 instead of using the general framework. */
7127 use_return_register ();
7129 /* Fix up any gotos that jumped out to the outermost
7130 binding level of the function.
7131 Must follow emitting RETURN_LABEL. */
7133 /* If you have any cleanups to do at this point,
7134 and they need to create temporary variables,
7135 then you will lose. */
7136 expand_fixups (get_insns ());
7140 get_arg_pointer_save_area (f)
7143 rtx ret = f->x_arg_pointer_save_area;
7147 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7148 f->x_arg_pointer_save_area = ret;
7151 if (f == cfun && ! f->arg_pointer_save_area_init)
7155 /* Save the arg pointer at the beginning of the function. The
7156 generated stack slot may not be a valid memory address, so we
7157 have to check it and fix it if necessary. */
7159 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7160 seq = gen_sequence ();
7163 push_topmost_sequence ();
7164 emit_insn_after (seq, get_insns ());
7165 pop_topmost_sequence ();
7171 /* Extend a vector that records the INSN_UIDs of INSNS (either a
7172 sequence or a single insn). */
7175 record_insns (insns, vecp)
7179 if (GET_CODE (insns) == SEQUENCE)
7181 int len = XVECLEN (insns, 0);
7182 int i = VARRAY_SIZE (*vecp);
7184 VARRAY_GROW (*vecp, i + len);
7187 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
7193 int i = VARRAY_SIZE (*vecp);
7194 VARRAY_GROW (*vecp, i + 1);
7195 VARRAY_INT (*vecp, i) = INSN_UID (insns);
7199 /* Determine how many INSN_UIDs in VEC are part of INSN. */
7202 contains (insn, vec)
7208 if (GET_CODE (insn) == INSN
7209 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7212 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7213 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7214 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7220 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7221 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7228 prologue_epilogue_contains (insn)
7231 if (contains (insn, prologue))
7233 if (contains (insn, epilogue))
7239 sibcall_epilogue_contains (insn)
7242 if (sibcall_epilogue)
7243 return contains (insn, sibcall_epilogue);
7248 /* Insert gen_return at the end of block BB. This also means updating
7249 block_for_insn appropriately. */
7252 emit_return_into_block (bb, line_note)
7258 p = NEXT_INSN (bb->end);
7259 end = emit_jump_insn_after (gen_return (), bb->end);
7261 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7262 NOTE_LINE_NUMBER (line_note), PREV_INSN (bb->end));
7264 #endif /* HAVE_return */
7266 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7268 /* These functions convert the epilogue into a variant that does not modify the
7269 stack pointer. This is used in cases where a function returns an object
7270 whose size is not known until it is computed. The called function leaves the
7271 object on the stack, leaves the stack depressed, and returns a pointer to
7274 What we need to do is track all modifications and references to the stack
7275 pointer, deleting the modifications and changing the references to point to
7276 the location the stack pointer would have pointed to had the modifications
7279 These functions need to be portable so we need to make as few assumptions
7280 about the epilogue as we can. However, the epilogue basically contains
7281 three things: instructions to reset the stack pointer, instructions to
7282 reload registers, possibly including the frame pointer, and an
7283 instruction to return to the caller.
7285 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7286 We also make no attempt to validate the insns we make since if they are
7287 invalid, we probably can't do anything valid. The intent is that these
7288 routines get "smarter" as more and more machines start to use them and
7289 they try operating on different epilogues.
7291 We use the following structure to track what the part of the epilogue that
7292 we've already processed has done. We keep two copies of the SP equivalence,
7293 one for use during the insn we are processing and one for use in the next
7294 insn. The difference is because one part of a PARALLEL may adjust SP
7295 and the other may use it. */
7299 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7300 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7301 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7302 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7303 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7304 should be set to once we no longer need
7308 static void handle_epilogue_set PARAMS ((rtx, struct epi_info *));
7309 static void emit_equiv_load PARAMS ((struct epi_info *));
7311 /* Modify SEQ, a SEQUENCE that is part of the epilogue, to no modifications
7312 to the stack pointer. Return the new sequence. */
7315 keep_stack_depressed (seq)
7319 struct epi_info info;
7321 /* If the epilogue is just a single instruction, it ust be OK as is. */
7323 if (GET_CODE (seq) != SEQUENCE)
7326 /* Otherwise, start a sequence, initialize the information we have, and
7327 process all the insns we were given. */
7330 info.sp_equiv_reg = stack_pointer_rtx;
7332 info.equiv_reg_src = 0;
7334 for (i = 0; i < XVECLEN (seq, 0); i++)
7336 rtx insn = XVECEXP (seq, 0, i);
7344 /* If this insn references the register that SP is equivalent to and
7345 we have a pending load to that register, we must force out the load
7346 first and then indicate we no longer know what SP's equivalent is. */
7347 if (info.equiv_reg_src != 0
7348 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7350 emit_equiv_load (&info);
7351 info.sp_equiv_reg = 0;
7354 info.new_sp_equiv_reg = info.sp_equiv_reg;
7355 info.new_sp_offset = info.sp_offset;
7357 /* If this is a (RETURN) and the return address is on the stack,
7358 update the address and change to an indirect jump. */
7359 if (GET_CODE (PATTERN (insn)) == RETURN
7360 || (GET_CODE (PATTERN (insn)) == PARALLEL
7361 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7363 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7365 HOST_WIDE_INT offset = 0;
7366 rtx jump_insn, jump_set;
7368 /* If the return address is in a register, we can emit the insn
7369 unchanged. Otherwise, it must be a MEM and we see what the
7370 base register and offset are. In any case, we have to emit any
7371 pending load to the equivalent reg of SP, if any. */
7372 if (GET_CODE (retaddr) == REG)
7374 emit_equiv_load (&info);
7378 else if (GET_CODE (retaddr) == MEM
7379 && GET_CODE (XEXP (retaddr, 0)) == REG)
7380 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7381 else if (GET_CODE (retaddr) == MEM
7382 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7383 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7384 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7386 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7387 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7392 /* If the base of the location containing the return pointer
7393 is SP, we must update it with the replacement address. Otherwise,
7394 just build the necessary MEM. */
7395 retaddr = plus_constant (base, offset);
7396 if (base == stack_pointer_rtx)
7397 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7398 plus_constant (info.sp_equiv_reg,
7401 retaddr = gen_rtx_MEM (Pmode, retaddr);
7403 /* If there is a pending load to the equivalent register for SP
7404 and we reference that register, we must load our address into
7405 a scratch register and then do that load. */
7406 if (info.equiv_reg_src
7407 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7412 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7413 if (HARD_REGNO_MODE_OK (regno, Pmode)
7414 && !fixed_regs[regno]
7415 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7416 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7418 && !refers_to_regno_p (regno,
7419 regno + HARD_REGNO_NREGS (regno,
7421 info.equiv_reg_src, NULL))
7424 if (regno == FIRST_PSEUDO_REGISTER)
7427 reg = gen_rtx_REG (Pmode, regno);
7428 emit_move_insn (reg, retaddr);
7432 emit_equiv_load (&info);
7433 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7435 /* Show the SET in the above insn is a RETURN. */
7436 jump_set = single_set (jump_insn);
7440 SET_IS_RETURN_P (jump_set) = 1;
7443 /* If SP is not mentioned in the pattern and its equivalent register, if
7444 any, is not modified, just emit it. Otherwise, if neither is set,
7445 replace the reference to SP and emit the insn. If none of those are
7446 true, handle each SET individually. */
7447 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7448 && (info.sp_equiv_reg == stack_pointer_rtx
7449 || !reg_set_p (info.sp_equiv_reg, insn)))
7451 else if (! reg_set_p (stack_pointer_rtx, insn)
7452 && (info.sp_equiv_reg == stack_pointer_rtx
7453 || !reg_set_p (info.sp_equiv_reg, insn)))
7455 if (! validate_replace_rtx (stack_pointer_rtx,
7456 plus_constant (info.sp_equiv_reg,
7463 else if (GET_CODE (PATTERN (insn)) == SET)
7464 handle_epilogue_set (PATTERN (insn), &info);
7465 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7467 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7468 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7469 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7474 info.sp_equiv_reg = info.new_sp_equiv_reg;
7475 info.sp_offset = info.new_sp_offset;
7478 seq = gen_sequence ();
7483 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7484 structure that contains information about what we've seen so far. We
7485 process this SET by either updating that data or by emitting one or
7489 handle_epilogue_set (set, p)
7493 /* First handle the case where we are setting SP. Record what it is being
7494 set from. If unknown, abort. */
7495 if (reg_set_p (stack_pointer_rtx, set))
7497 if (SET_DEST (set) != stack_pointer_rtx)
7500 if (GET_CODE (SET_SRC (set)) == PLUS
7501 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7503 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7504 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7507 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7509 /* If we are adjusting SP, we adjust from the old data. */
7510 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7512 p->new_sp_equiv_reg = p->sp_equiv_reg;
7513 p->new_sp_offset += p->sp_offset;
7516 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7522 /* Next handle the case where we are setting SP's equivalent register.
7523 If we already have a value to set it to, abort. We could update, but
7524 there seems little point in handling that case. Note that we have
7525 to allow for the case where we are setting the register set in
7526 the previous part of a PARALLEL inside a single insn. But use the
7527 old offset for any updates within this insn. */
7528 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7530 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7531 || p->equiv_reg_src != 0)
7535 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7536 plus_constant (p->sp_equiv_reg,
7540 /* Otherwise, replace any references to SP in the insn to its new value
7541 and emit the insn. */
7544 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7545 plus_constant (p->sp_equiv_reg,
7547 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7548 plus_constant (p->sp_equiv_reg,
7554 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7560 if (p->equiv_reg_src != 0)
7561 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7563 p->equiv_reg_src = 0;
7567 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7568 this into place with notes indicating where the prologue ends and where
7569 the epilogue begins. Update the basic block information when possible. */
7572 thread_prologue_and_epilogue_insns (f)
7573 rtx f ATTRIBUTE_UNUSED;
7577 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7580 #ifdef HAVE_prologue
7581 rtx prologue_end = NULL_RTX;
7583 #if defined (HAVE_epilogue) || defined(HAVE_return)
7584 rtx epilogue_end = NULL_RTX;
7587 #ifdef HAVE_prologue
7591 seq = gen_prologue ();
7594 /* Retain a map of the prologue insns. */
7595 if (GET_CODE (seq) != SEQUENCE)
7597 record_insns (seq, &prologue);
7598 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7600 seq = gen_sequence ();
7603 /* Can't deal with multiple successors of the entry block
7604 at the moment. Function should always have at least one
7606 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7609 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7614 /* If the exit block has no non-fake predecessors, we don't need
7616 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7617 if ((e->flags & EDGE_FAKE) == 0)
7623 if (optimize && HAVE_return)
7625 /* If we're allowed to generate a simple return instruction,
7626 then by definition we don't need a full epilogue. Examine
7627 the block that falls through to EXIT. If it does not
7628 contain any code, examine its predecessors and try to
7629 emit (conditional) return instructions. */
7635 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7636 if (e->flags & EDGE_FALLTHRU)
7642 /* Verify that there are no active instructions in the last block. */
7644 while (label && GET_CODE (label) != CODE_LABEL)
7646 if (active_insn_p (label))
7648 label = PREV_INSN (label);
7651 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7653 rtx epilogue_line_note = NULL_RTX;
7655 /* Locate the line number associated with the closing brace,
7656 if we can find one. */
7657 for (seq = get_last_insn ();
7658 seq && ! active_insn_p (seq);
7659 seq = PREV_INSN (seq))
7660 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7662 epilogue_line_note = seq;
7666 for (e = last->pred; e; e = e_next)
7668 basic_block bb = e->src;
7671 e_next = e->pred_next;
7672 if (bb == ENTRY_BLOCK_PTR)
7676 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7679 /* If we have an unconditional jump, we can replace that
7680 with a simple return instruction. */
7681 if (simplejump_p (jump))
7683 emit_return_into_block (bb, epilogue_line_note);
7687 /* If we have a conditional jump, we can try to replace
7688 that with a conditional return instruction. */
7689 else if (condjump_p (jump))
7693 ret = SET_SRC (PATTERN (jump));
7694 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
7695 loc = &XEXP (ret, 1);
7697 loc = &XEXP (ret, 2);
7698 ret = gen_rtx_RETURN (VOIDmode);
7700 if (! validate_change (jump, loc, ret, 0))
7702 if (JUMP_LABEL (jump))
7703 LABEL_NUSES (JUMP_LABEL (jump))--;
7705 /* If this block has only one successor, it both jumps
7706 and falls through to the fallthru block, so we can't
7708 if (bb->succ->succ_next == NULL)
7714 /* Fix up the CFG for the successful change we just made. */
7715 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7718 /* Emit a return insn for the exit fallthru block. Whether
7719 this is still reachable will be determined later. */
7721 emit_barrier_after (last->end);
7722 emit_return_into_block (last, epilogue_line_note);
7723 epilogue_end = last->end;
7724 last->succ->flags &= ~EDGE_FALLTHRU;
7729 #ifdef HAVE_epilogue
7732 /* Find the edge that falls through to EXIT. Other edges may exist
7733 due to RETURN instructions, but those don't need epilogues.
7734 There really shouldn't be a mixture -- either all should have
7735 been converted or none, however... */
7737 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7738 if (e->flags & EDGE_FALLTHRU)
7744 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7746 seq = gen_epilogue ();
7748 #ifdef INCOMING_RETURN_ADDR_RTX
7749 /* If this function returns with the stack depressed and we can support
7750 it, massage the epilogue to actually do that. */
7751 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7752 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7753 seq = keep_stack_depressed (seq);
7756 emit_jump_insn (seq);
7758 /* Retain a map of the epilogue insns. */
7759 if (GET_CODE (seq) != SEQUENCE)
7761 record_insns (seq, &epilogue);
7763 seq = gen_sequence ();
7766 insert_insn_on_edge (seq, e);
7773 commit_edge_insertions ();
7775 #ifdef HAVE_sibcall_epilogue
7776 /* Emit sibling epilogues before any sibling call sites. */
7777 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7779 basic_block bb = e->src;
7784 if (GET_CODE (insn) != CALL_INSN
7785 || ! SIBLING_CALL_P (insn))
7789 seq = gen_sibcall_epilogue ();
7792 i = PREV_INSN (insn);
7793 newinsn = emit_insn_before (seq, insn);
7795 /* Retain a map of the epilogue insns. Used in life analysis to
7796 avoid getting rid of sibcall epilogue insns. */
7797 record_insns (GET_CODE (seq) == SEQUENCE
7798 ? seq : newinsn, &sibcall_epilogue);
7802 #ifdef HAVE_prologue
7807 /* GDB handles `break f' by setting a breakpoint on the first
7808 line note after the prologue. Which means (1) that if
7809 there are line number notes before where we inserted the
7810 prologue we should move them, and (2) we should generate a
7811 note before the end of the first basic block, if there isn't
7814 ??? This behaviour is completely broken when dealing with
7815 multiple entry functions. We simply place the note always
7816 into first basic block and let alternate entry points
7820 for (insn = prologue_end; insn; insn = prev)
7822 prev = PREV_INSN (insn);
7823 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7825 /* Note that we cannot reorder the first insn in the
7826 chain, since rest_of_compilation relies on that
7827 remaining constant. */
7830 reorder_insns (insn, insn, prologue_end);
7834 /* Find the last line number note in the first block. */
7835 for (insn = BASIC_BLOCK (0)->end;
7836 insn != prologue_end && insn;
7837 insn = PREV_INSN (insn))
7838 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7841 /* If we didn't find one, make a copy of the first line number
7845 for (insn = next_active_insn (prologue_end);
7847 insn = PREV_INSN (insn))
7848 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7850 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7851 NOTE_LINE_NUMBER (insn),
7858 #ifdef HAVE_epilogue
7863 /* Similarly, move any line notes that appear after the epilogue.
7864 There is no need, however, to be quite so anal about the existence
7866 for (insn = epilogue_end; insn; insn = next)
7868 next = NEXT_INSN (insn);
7869 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7870 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7876 /* Reposition the prologue-end and epilogue-begin notes after instruction
7877 scheduling and delayed branch scheduling. */
7880 reposition_prologue_and_epilogue_notes (f)
7881 rtx f ATTRIBUTE_UNUSED;
7883 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7884 rtx insn, last, note;
7887 if ((len = VARRAY_SIZE (prologue)) > 0)
7891 /* Scan from the beginning until we reach the last prologue insn.
7892 We apparently can't depend on basic_block_{head,end} after
7894 for (insn = f; insn; insn = NEXT_INSN (insn))
7896 if (GET_CODE (insn) == NOTE)
7898 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7901 else if (contains (insn, prologue))
7913 /* Find the prologue-end note if we haven't already, and
7914 move it to just after the last prologue insn. */
7917 for (note = last; (note = NEXT_INSN (note));)
7918 if (GET_CODE (note) == NOTE
7919 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7923 next = NEXT_INSN (note);
7925 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7926 if (GET_CODE (last) == CODE_LABEL)
7927 last = NEXT_INSN (last);
7928 reorder_insns (note, note, last);
7932 if ((len = VARRAY_SIZE (epilogue)) > 0)
7936 /* Scan from the end until we reach the first epilogue insn.
7937 We apparently can't depend on basic_block_{head,end} after
7939 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7941 if (GET_CODE (insn) == NOTE)
7943 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7946 else if (contains (insn, epilogue))
7956 /* Find the epilogue-begin note if we haven't already, and
7957 move it to just before the first epilogue insn. */
7960 for (note = insn; (note = PREV_INSN (note));)
7961 if (GET_CODE (note) == NOTE
7962 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7966 if (PREV_INSN (last) != note)
7967 reorder_insns (note, note, PREV_INSN (last));
7970 #endif /* HAVE_prologue or HAVE_epilogue */
7973 /* Mark P for GC. */
7976 mark_function_status (p)
7979 struct var_refs_queue *q;
7980 struct temp_slot *t;
7987 ggc_mark_rtx (p->arg_offset_rtx);
7989 if (p->x_parm_reg_stack_loc)
7990 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7994 ggc_mark_rtx (p->return_rtx);
7995 ggc_mark_rtx (p->x_cleanup_label);
7996 ggc_mark_rtx (p->x_return_label);
7997 ggc_mark_rtx (p->x_save_expr_regs);
7998 ggc_mark_rtx (p->x_stack_slot_list);
7999 ggc_mark_rtx (p->x_parm_birth_insn);
8000 ggc_mark_rtx (p->x_tail_recursion_label);
8001 ggc_mark_rtx (p->x_tail_recursion_reentry);
8002 ggc_mark_rtx (p->internal_arg_pointer);
8003 ggc_mark_rtx (p->x_arg_pointer_save_area);
8004 ggc_mark_tree (p->x_rtl_expr_chain);
8005 ggc_mark_rtx (p->x_last_parm_insn);
8006 ggc_mark_tree (p->x_context_display);
8007 ggc_mark_tree (p->x_trampoline_list);
8008 ggc_mark_rtx (p->epilogue_delay_list);
8009 ggc_mark_rtx (p->x_clobber_return_insn);
8011 for (t = p->x_temp_slots; t != 0; t = t->next)
8014 ggc_mark_rtx (t->slot);
8015 ggc_mark_rtx (t->address);
8016 ggc_mark_tree (t->rtl_expr);
8017 ggc_mark_tree (t->type);
8020 for (q = p->fixup_var_refs_queue; q != 0; q = q->next)
8023 ggc_mark_rtx (q->modified);
8026 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
8027 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
8028 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
8029 ggc_mark_tree (p->x_nonlocal_labels);
8031 mark_hard_reg_initial_vals (p);
8034 /* Mark the struct function pointed to by *ARG for GC, if it is not
8035 NULL. This is used to mark the current function and the outer
8039 maybe_mark_struct_function (arg)
8042 struct function *f = *(struct function **) arg;
8047 ggc_mark_struct_function (f);
8050 /* Mark a struct function * for GC. This is called from ggc-common.c. */
8053 ggc_mark_struct_function (f)
8057 ggc_mark_tree (f->decl);
8059 mark_function_status (f);
8060 mark_eh_status (f->eh);
8061 mark_stmt_status (f->stmt);
8062 mark_expr_status (f->expr);
8063 mark_emit_status (f->emit);
8064 mark_varasm_status (f->varasm);
8066 if (mark_machine_status)
8067 (*mark_machine_status) (f);
8068 if (mark_lang_status)
8069 (*mark_lang_status) (f);
8071 if (f->original_arg_vector)
8072 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
8073 if (f->original_decl_initial)
8074 ggc_mark_tree (f->original_decl_initial);
8076 ggc_mark_struct_function (f->outer);
8079 /* Called once, at initialization, to initialize function.c. */
8082 init_function_once ()
8084 ggc_add_root (&cfun, 1, sizeof cfun, maybe_mark_struct_function);
8085 ggc_add_root (&outer_function_chain, 1, sizeof outer_function_chain,
8086 maybe_mark_struct_function);
8088 VARRAY_INT_INIT (prologue, 0, "prologue");
8089 VARRAY_INT_INIT (epilogue, 0, "epilogue");
8090 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");